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  • Hacker Public Radio

    HPR4629: What did I do at work today? Part 2

    30/04/2026
    This show has been flagged as Clean by the host.

    This show is about developing features for a web application. The technology used is
    ASP.Net WebForms
    , the programming language is
    Visual Basic .Net
    along with HTML and CSS and the development environment is Windows 11 running under a virtual machine in Linux, with
    Visual Studio
    and
    SQL Server
    as the database. Other tools used are
    Git
    ,
    Github
    ,
    Joplin
    and
    Dropbox
    ,
    Google Gemini
    and a tool called
    Beyond Compare
    .









    ResourceRowControl.ascx.vb




    Public WriteOnly Property ResourceObject As Resource
    Set(obj As Resource)
    If obj IsNot Nothing Then
    HiddenResourceID.Value = CStr(obj.ResourceID)
    HiddenResourceTypeID.Value = CStr(obj.ResourceTypeID)
    Resource.Text = obj.ResourceName
    Type.Text = obj.ResourceTypeName
    Available.Checked = obj.ResourceAvailable
    End If
    End Set
    End Property

    Private Sub Available_CheckedChanged(sender As Object, e As EventArgs) Handles Available.CheckedChanged
    Dim objResource As New Resource
    With objResource
    .ResourceID = ResourceID
    .ResourceName = Resource.Text
    .ResourceTypeID = ResourceTypeID
    .ResourceAvailable = Available.Checked
    End With
    objResource.Add()
    End Sub









    ResourceRowControl.ascx




    <tr>
    <td>
    <asp:Label runat="server" ID="Resource"></asp:Label>
    </td>
    <td>
    <asp:Label runat="server" ID="Type"></asp:Label>
    </td>
    <td>
    <asp:Button runat="server" ID="Edit" CssClass="Pointer fa" BackColor="White" ForeColor="#741E43" BorderStyle="None" Text="&#xf044;" />
    </td>
    <td>
    <asp:Button runat="server" ID="Delete" CssClass="Pointer fa" BackColor="White" ForeColor="#741E43" BorderStyle="None" Text="&#xf1f8;"
    OnClientClick="return DeleteResourceRow(this.id)" />
    </td>
    <td>
    <label class="toggle-checkbox">
    <asp:CheckBox runat="server" ID="Available" AutoPostBack="true" />
    <span class="slider"></span>
    </label>
    </td>
    </tr>











    Provide feedback on this episode.
  • Hacker Public Radio

    HPR4628: Nuclear Power Technology Follow Up

    29/04/2026
    This show has been flagged as Clean by the host.

    --------------------







    01 Introduction







    This is a follow up to my 8 part series on nuclear power.



    In this episode I will answer questions posed by listeners in the comments to the series.



    I would like to start by thanking these people for taking the time to submit interesting questions.







    --------------------







    Costs of Small Versus Large Reactors







    02



    brian-in-ohio asked two questions







    The first was for a cost comparison between large and small reactors.



    The second was for nuclear plant safety compared to conventional power plants.











    03 Answer



    I think that any answer to the second question is going to be perceived by some people as politically controversial, so it's probably not a good topic for HPR to address.







    04



    The first question though about cost of small versus large reactors is an interesting one, although not one that is easy to give an answer to.



    I will restrict the answer to just grid scale electric power production and ignore use cases such as industrial process heat or power for remote mines and communities.







    05



    This question comes down to economies of scale versus economies of replication.



    Economies of scale centre around increased efficiencies of use of materials and labour when making something bigger.



    For example, the amount of steel used by a pipe increases linearly with its diameter, but the amount of fluid that it transports increases with the square.







    06



    Economies of replication come from increasing efficiencies which result from serial production. As you repeat the same design over and over again, you learn how to do things better and make fewer mistakes.







    07



    The exact same principles apply to shipbuilding.



    Indeed, a lot of the inspiration for Small Modular Reactors comes from the shipbuilding industry.



    If you build a series of identical ships, then each subsequent ship will cost less and be built faster.



    There are of course diminishing returns to this process, so the improvements are less with each additional unit and after a sufficient number of units the cost and time reductions level off.







    08



    However, this doesn't discount the benefits of economies of scale.



    What it does mean is that there are two ways of approaching the problem, and which way works in any given scenario depends on such conditions as



    how big the local electricity market is



    how fast the demand for electricity is growing,



    the ownership and financing structure of the electricity market, and



    the geography of the area, which may pose limits on the number of sites.







    09



    According to the finance people who have crunched the numbers, there are two sizes of reactor which make the most sense in the above context.



    These are 300 MW and 1000 MW.



    However, take those as very rough numbers rather than immutable laws of nature and other sizes may work as well.







    10



    The key point is that there are cases to be made for both small and large reactors, with the large reactor being several times the size of the small one.







    11



    An additional factor is that building only one reactor does not reap the benefits of efficiency of replication.



    You need to build a series of them on the same site.



    So if you are building a power plant, you don't build a power plant that has just one reactor unless you are in a small market which can only use that much power.



    Instead, you should build between 4 and 6 reactors in sequence next to one another.







    12



    If you are supply a large population with a growing demand for electricity, then 4 or 6 large 1000 MW reactors gains both economies of scale and economies of replication.



    If you are supplying a smaller population with slow growth in demand for electricity, then 4 or 6 300 MW reactors at least gets you economies of replication.







    13



    There is what could be viewed as an interesting example in terms of the above taking place just east of Toronto.



    There they are building four 300 MW SMRs on a site next to an existing nuclear power plant.







    14



    Here are the cost estimates from the Government of Ontario.



    All costs are in Canadian dollars.



    Unit 1 is $6.1 billion, plus $1.6 billion in costs which are shared by all four unit.s



    Unit 2 is $4.9 billion.



    Unit 3 is $4.2 billion.



    Unit 4 is $4.1 billion.







    15



    As you can see, building a series of reactors sequentially on the same site results in declining overall costs.



    They are very confident in these costs as they used data from a series of major nuclear power plant refurbishment projects in Ontario which have been coming in on time and on budget.







    16



    Construction began last year and the plant is expected to have a 65 year operating life.







    17



    However, the province of Ontario also has plans for expansion of electrical generation by about 15,000 MW by 2050 in order to meet net zero targets.







    18



    Given the heavy concentration of population in the Toronto region,



    and the very high cost and difficulty of building long distance transmission lines,



    and the limited number of sites which could host new power generation facilities of any sort,



    I suspect it is quite likely that subsequent reactors will be large 1,000 MW ones rather than SMRs.







    19



    The Wesleyville site (which is further east of Toronto) is tentatively scheduled for a 10,000 MW nuclear power plant.



    That would seem to make ten 1,000 MW reactors more likely than 34 300 MW reactors.







    20



    I don't have a comparable set of numbers for building large reactors to give an exact apples to apples comparison of costs.



    Different countries use different accounting and financing systems, and finance makes a huge difference to overall costs for nuclear power as operating costs are a relatively small share of the total.







    21



    Now to look at another side of this equation, the provinces of Saskatchewan and New Brunswick wish to replace their coal fired power plants with nuclear power plants.



    The populations of these provinces are too small to absorb a large new power plant into their grids, and studies assuming large reactors have foundered on this issue.







    22



    New Brunswick already have a nuclear power plant, but it was build in the days when reactors were much smaller.



    Both provinces however are very interested in small reactors, even individual ones, in order to replace the coal fired plants that are of similar size.







    23



    I think this covers the cost versus size issue.



    The more I look into it, the more it becomes apparent that there is no simple one size fits all answer but rather there are a series of trade-offs which must be taken in light of local circumstances.







    --------------------







    MOX Fuel in the USA







    24



    The next question comes from mnw who asked about the use of MOX fuel in the USA.







    25



    mnw asked



    I am enjoying and look forward to the rest of the series. Do you think the US will ever wake up and start recycling its spent fuel? It seems like such a huge waste just to try and keep a small amount of fuel away from"the bad guys" or whatever they are imagining.











    Answer



    26



    My answer to this is as follows.



    I think I've addressed this in the original series, although not directly with respect to the US so I can provide some more detail on that aspect of it.







    27



    First though I will review what plutonium-uranium mixed oxide (MOX) fuel is.



    As mentioned in previous episodes, military grade plutonium is not the same as the plutonium which comes out of commercial power reactors.



    Just as military grade uranium requires nearly pure U-235 isotope, military grade plutonium requires nearly pure Pu-239 isotope.







    28



    What comes out of a commercial power reactor as spent fuel is not usable for weapons purposes as the proportion of Pu-239 is much too low.



    However, plutonium recovered from spent fuel can be used as fuel for nuclear reactors in place of uranium 235 when mixed with uranium 238 either left over from enrichment or extracted from spent fuel.



    This is what is known as MOX fuel.











    29



    To look at the US history of this however, here's the sequence of events.



    The US banned fuel reprocessing in 1976.



    However, this ban was repealed in 1981.







    30



    In 2005, the US began building a mixed-oxide (MOX) fuel plant at Savannah River in the state of South Carolina.



    However, this plant was not intended as a normal commercial operation and it was not intended to recycle commercial nuclear power plant fuel.



    It was instead intended to convert surplus military grade plutonium into commercial fuel in order to get rid of it as part of an arms control program.







    31



    The program was suspended in 2018.



    There were apparently many complex political issues involved in these on-again off-again decisions and I won't pretend to have the time or interest to explore all the details nor do I think most listeners would be interested in hearing abou them.







    32



    As of March 2026, the US are looking at reviving part of the Savannah River plant to produce limited amounts of fuel for testing of advanced reactors.



    The issue driving this is the shortage of uranium enriched to just below 20%.



    This fuel is used in certain types of small SMR.







    33



    The main commercial supplier of this material was a plant in Russia, but "certain events in Europe in recent years" shall we say, have resulted in that supply no longer being available to commercial operations in the US.



    MOX fuel based on surplus weapons grade plutonium is intended as a short term quick fix for that problem.







    34



    Another driving force is legal requirements following from domestic commitments for the US government to dispose of certain stockpiles of weapons grade plutonium from certain sites in the US where it is "temporarily" stored, and the solution to that is seen as burning it up in power reactors.







    35



    So the history is the US banned fuel reprocessing.



    Then a few years later they un-banned it.



    Then the US government started building a MOX plant which was intended to get rid of surplus weapons grade material by burning it up in power reactors.



    Then they decided they didn't want to do that.



    Then they decided they may want to make MOX fuel after all to replace supplies of special grades of fuel for experimental or prototype reactors.







    36



    What is missing from the above history is any actual interest from the US commercial nuclear industry in MOX fuel.



    The reason for this is, as mentioned in the previous episodes, uranium is so cheap and abundant that fuel made from fresh uranium is cheaper than MOX fuel.







    37



    Some countries such as France wish to recycle spent fuel to reduce their dependence upon imports.



    Recall that France's drive to build nuclear power plants was in response to the 1970s era energy crisis when oil imports from the Middle East were suddenly cut off.



    However, the US are not concerned about this issue and so do not make it national security policy as France did.







    38



    As a result, US commercial demand is for cheaper fuel made from fresh uranium rather than for MOX fuel.



    Until such time as fresh uranium greatly increases in price there is little economic incentive for the use of MOX fuel in the US.







    39



    However, there is another aspect to this.



    If you recall in previous episodes I described molten salt reactors which used dissolved uranium fuel.



    These reactors inherently reprocess fuel as part of their normal operation.



    They just do it as part of maintaining the molten salt chemistry at the correct values rather than doing it as a separate process.







    40



    If these types of reactors become widely used then they would be achieving the same thing as creating MOX fuel, but without an explicit separate step.







    41



    As a final footnote to the above, the US has almost exclusively use enriched uranium light water reactors.



    As mentioned in previous episodes, there are ways of recycling spent fuel from light water reactors which do not involve chemically reprocessing it to make MOX fuel.







    42



    Experiments have been done involving South Korea, China, and Canada which take spent fuel from light water reactors and repackage it to fit it into natural uranium heavy water reactors.



    What is used up or "spent" fuel for a light water reactor is high grade fuel to a natural uranium reactor.



    However, the US has, for whatever reason, never built commercial natural uranium reactors such as are used in a number of other countries around the world.







    43



    If they were to do so, then nuclear fuel could be used twice, once in a light water reactor, and again in a natural uranium reactor, all without having to turn it into MOX fuel in a separate reprocessing step.



    However, this particular alternative would likely face the same issue in the sense that fresh fuel would still be cheaper than reusing spent fuel.











    --------------------







    A Variety of Questions from Clinton







    44



    Next we have a variety of questions from Clinton.







    Clinton asked







    I would like some commentary in the current situation,



    why has hinkley gone off the rails,



    the new american approach,



    the odd things done after fukushima,



    the new radiation rules in the states.











    45 Question 1



    why has hinkley gone off the rails,







    46 Answer



    The question refers to cost overruns at the Hinkley Point nuclear power project in the UK.







    The UK government looked into this issue in a more general sense in 2025.



    They published a report on it titled







    Nuclear Regulatory Review 2025



    Enabling nuclear delivery through regulatory reform



    John Fingleton







    There is a link to the report in the show notes.



    https://assets.publishing.service.gov.uk/media/692080f75c394e481336ab89/nuclear-regulatory-review-2025.pdf







    47



    As the report is 162 pages long, I won't try to cover it all in this answer. I will however give a few simple examples.







    The report focuses on civilian nuclear power and the defence nuclear industry as well.



    However it also draws examples from outside the nuclear industry to show that the problem is not limited to nuclear.



    It shows that the same problems exist in the offshore wind industry, and in the HS2 High Speed Rail project.







    48



    In the view of the authors of the report, the essence of the problem seems to be a lack of any degree of proportionality in terms of mitigating negative effects from any project.



    Big nuclear projects make the headlines because they are inherently big projects, but as I have just mentioned, they affect things like wind power development and rail transport as well.







    49



    I will pick one example from Hinkley Point specifically.



    This is "Case Study: Hinkley Point C Fish Protection"



    A summary of this is that they spent £700 million of additional money on the cooling water intakes to protect an estimated 0.083 salmon per year, along with 0.028 sea trout, 6 river lamprey, 18 Allis shad, and somewhere between 100 and 528 twaite shad.



    The report points out that there are ways to protect far more fish for far less money by spending it in other areas, and gives some examples.







    Again, this problem is not limited to nuclear power, and they give similar examples connected with offshore wind development and HS2 High Speed Rail.







    50



    I would like to emphasize that I am not expressing an opinion on whether or not any of these decisions were good or bad ones or whether the money was well spent.



    I am just summarizing the report's explanation of why large projects of all sorts initiated and approved by the UK parliament were not turning out as initially expected.







    I will leave it up to people in the UK to decide whether or not they are satisfied with the current situation.







    51 Question 2



    the new american approach,







    52 Answer







    The US have apparently announced changes to their regulatory system.



    I don't know enough about the subject to really judge the practical effects of regulation within the US.



    However, I have read and listened to many interviews of people from both the industry and the regulatory side of things who are from outside the US but are familiar with it.



    They generally contrast two different approaches to regulation.



    On the one hand there is the US approach, which they see as being more of a box ticking exercise than an in depth safety review.



    This makes it very hard to get a design other than a traditional PWR or BWR approved in the US.







    53



    It has the advantage from the regulator side of things though in that it reduces the amount of work required as it primarily requires just following a set of defined procedures.



    These people then contrast that approach with the one used in the UK and in Canada, both of which they see as being very similar to one another.



    In those two countries, regulators work with industry to review designs from basic principles rather than just seeing if it meets a pre-defined list of criteria.



    This is a results oriented system rather than a process oriented system as used in the US.







    54



    As a result of this, designers of new nuclear reactors are going to the UK and Canada first to go through preliminary review there, and only going to the US later.



    What designers are looking for is feedback on their design as they go along in order to align the design with what safety regulators see as being required from their standpoint.



    They want to go into a review process before the design is finalized so they can get guidance on how they should approach things rather than trying to add safety as additional features on top of a finished design.







    55



    It would take someone with deep familiarity with nuclear regulation systems to understand the practical effects of recent changes in US regulatory systems, but it is quite possible that people within the regulatory structure in the US have been taking the above on board and trying to adapt to current circumstances.



    However, I can only speculate on that.



    This is about the best answer that I can give.











    56 Question 3



    the odd things done after fukushima,







    57 Answer







    This covers a lot of topics, some of which are probably political and so are not suited to HPR.



    I will try to list a few events however.



    As a brief summary if the Fukushima events go however, a historic scale earthquake and tsunami in Japan in 2011 caused huge loss of life and widespread damage.



    About 20,000 people were killed by the earthquake and tsunami.







    Three nuclear reactors based on 1960s era GE BWR designs were seriously damaged by hydrogen explosions caused by loss of power to backup generators when they were flooded by the tsunami.



    However, there were no radiation related deaths or cases of radiation sickness.







    58



    Following events in Japan was a general review of designs around the world, with various improvements made in some areas, particularly backup generators and hydrogen management.







    It seems to be conventional wisdom that the Fukushima event caused a number of countries to decide to phase out nuclear power.







    59



    However, when I tried to make a list of such countries for this episode I found things were not as is often heard.



    The countries which decided to get rid of nuclear power had largely started down that road at least a decade before then and generally for reasons unrelated to any specific events outside of their own country.



    In other cases they reversed that decision or are in the process of doing so.



    Japan itself has restarted many of their nuclear power plants and plant to replace decommissioned nuclear power plants with new ones, although many of the older and smaller ones were considered not economically worth upgrading at this point in their life to restart them.







    60



    The one possible exception to this may be Taiwan which decided to phase out nuclear power in 2016.



    However, I don't know enough about Taiwanese politics to state with any confidence that their decision in 2016 was based on anything related to events in Japan, or whether in fact they were a byproduct of other political changes within Taiwan and the shut down of nuclear plants happened to be carried along with those.



    Currently Taiwan get their electricity primarily from natural gas and coal.







    61



    Meanwhile across mainland Asia from Turkey to China, large numbers of nuclear power plants were built or are under construction.



    Taken together on a global scale, did anything really change after Fukushima, or did the countries which had already decided to close down their nuclear power plants simply continue to do so, and those countries who decided they wanted more of them continue to build them?



    That's a good question for which I don't think anyone has the perspective to answer at this point.







    62



    Another side of this which is hard to disentangle from it though is the increased use of natural gas for electric power generation which was happening at around the same time.



    Increased use of fracking in a number of countries, plus increased supplies from Russia and LNG from the Middle East and other places resulted in falls in natural gas prices in many places.



    Since combined cycle natural gas turbines form the main competitor to nuclear power, anything which improves the economics of natural gas will act to reduce demand for nuclear power.



    This makes it hard to decide to what degree the reduction in the number of reactors being built was due to the political effects of the earthquake and tsunami and to what degree it was due to cheaper natural gas through fracking and other means.







    I'll leave that question at that.







    63 Question 4



    the new radiation rules in the states.







    64 Answer







    I'm not deeply familiar with US radiation rules, but I will attempt to answer the question.







    Apparently there are wide variety of different things being addressed, only some of which have any relevance to the nuclear power industry.



    One of these is an epidemiological study on the current exposure limits for workers in the nuclear industry.



    This study will take place over about 5 years.







    In the end it may not result in any changes.



    This is for a number of reasons.







    65



    One is that US exposure thresholds for workers are currently aligned with international standards.



    It would be difficult for the US industry to operate on a different basis than the rest of the world when supply chains are global and kit is designed to meet currently recognized standards.







    Another is that apparently the nuclear industry are not, so far as I can discern, asking for any changes to limits.



    They instead are looking for changes to how some of the details are being applied, such as for example the criteria for deciding when respirators are required in low risk environments.







    66



    Some point to recent changes in UK regulations as an example of what they are looking for.



    I will post a link to the new (November of 2025) UK regulations in the show notes.



    https://www.gov.uk/government/publications/nuclear-industry-principles-to-guide-the-application-of-as-low-as-reasonably-practicable-alarp-and-best-available-techniques-bat/ways-of-working-principles-to-guide-the-application-of-alarp-and-bat-in-the-nuclear-industry-accessible-webpage







    This is about as much detail as I think I can comment on when it comes to this question, as I think it is a subject that requires a fair bit more practical knowledge of than I have in order to give a thorough and balanced answer.











    --------------------







    67 Question from Antoine







    Were/are the designs patented?







    Hi, Whiskeyjack.



    Nice ep.



    You said AGR, based on Magnox, was a nuclear reactor type that did not sell well outside the UK. I then started thinking if it were (is) possible to another countries to develop by themselves based on that project, or if it had (has) a commercial restriction for exploration of the technology.



    I have yet to listen to the following episodes (doing little by little) and may learn better on the choices, but I felt free to present the question by now...



    Thanks!







    68 Answer



    This is a very good question because it offers the opportunity to talk about a number of interesting things that haven't been touched on yet.







    Let's cover a bit of background first.







    69



    A patent is a time limited right to exploit a defined bit of valuable technical knowledge.



    Patents were involved from the very earliest days of commercial nuclear power, and I will give an example of this later.



    A key point to keep in mind though is that the nuclear power field moves very slowly and it takes a long time for new knowledge to make it from the lab to commercial application.



    Patents will often expire before they reach the point where they can be used.







    70



    Contracts on the other hand are legally enforceable agreements between two parties.



    A contract may have a time limited life, but that is an arrangement between the parties.



    A commercial nuclear power plant is a very large and complex bit of kit and not easily copied in detail.



    It can be far more effective to cover designs under contracts and licenses than to rely on patents.



    If a country wished to build their own nuclear power plants rather than buying them from someone else, there are a large number of companies who have commercial designs they are willing to license to third parties for them to build themselves.



    Indeed a number of these companies base their business around licensing of designs or have other reasons for wishing to do so.







    71



    From a licensee perspective, it could take decades of work and hundreds of millions or even billions of dollars to take a design from first principle to the ready to build state, wheras licensing a design give you a proven design right away.







    As mentioned in previous episodes, there many types of reactor in the world.



    The selection of what sort of reactor a country decides to buy often depends more on commercial considerations revolving around licensing terms and conditions than it does with respect to any technical considerations.







    Here's an example which shows how South Korea decided to license a design, build it for themselves, and then export it to other countries.







    72



    KunMo Chung - Professor at the Korea Advanced Institute of Science and Technology, stated in an interview in 2019 that South Korea wanted to standardize on a single reactor technology in the early 1980s.







    They had reactors from multiple different vendors, but wanted to license an existing successful design to produce for themselves and for the export market. One of the major factors in deciding to standardize was to allow them to improve operator training by focusing on one design.







    Professor Chung stated that one of the key factors in selecting a design from ABB-Combustion Engineering was that he personally knew and had a good relationship with the Chief Technical Officer of ABB-Combustion Engineering going back to a time when Professor Chung had been studying and working in the USA.







    73



    On their side, ABB-Combustion Engineering were having financial problems and they needed a partner to help further develop their new PWR design. Also they stood to gain revenue from this partnership as well.







    Based on this relationship, the two sides came to a business agreement and South Korea began producing reactors based on this design, while also continuing to develop and improve it further.











    74



    Here's an example of a case where the developers of a promising technology decided that they had more to gain by not patenting their technology.



    Instead they decided to freely share their information in order to get other researchers elsewhere to help to advance the technology so that all could benefit from it.







    75



    In an interview Wacław Gudowski - Prof. Emeritus, Royal Institute of Technology KTH Stockholm



    stated that the Soviets and later the Russian were the leaders in lead-bismuth cooled reactors.



    These reactors use lead-bismuth liquid metal alloy as a coolant.



    In the 1990s the Russian institute working on commercializing this technology were working with Western partners on nuclear technology in general.



    They considered patenting this technology, but in the end decided to simply publish it openly.



    76



    Professor Gudowski had even smuggled $60,000 in cash into Russia to finance the patent application in order to get the Russian institute to publish their technology, but the money was not needed.



    They based this decision on the judgment that it would take 20 years of R&D before the technology was ready for the commercial market, so they wouldn't see a penny on any patents anyway.



    They were right on this, as it was another 20 years of R&D in Europe, Russia, China, and Korea before lead-bismuth technology was ready for commercial use.



    77



    It had already seen use in submarine reactors, but the commercial market demanded a more thoroughly developed technology to satisfy commercial needs.



    By deciding to not patent the technology, the original developers gained from shared R&D rather than chasing the illusary gains from patent licenses on technology that was not ready for the commercial market anyway.











    78



    I said that patents were involved in nuclear technology from the very earliest days, and I will now turn to that story.



    When I say the earliest days, I mean probably earlier than you are imaging.



    I am talking about before WWII.







    79



    First though I need to give some background information.



    France and Britain were working on nuclear weapons from the very earliest days of WWII.



    In Britain's case this was called Tube Alloys.



    Canada also was conducting nuclear experiments, including building an "atomic pile", but it's not clear if this had any clear practical goals or was done to understand the physics better.







    80



    If you read the Wikipedia version of history, it states that Tube Alloys was merged into the Manhattan Project.



    However, participants have stated in interviews that this was not the case, and the Quebec Agreement which supposedly merged them makes no such mention of any merger of the projects, just the setting up of a board to coordinate efforts between the three countries, that is the US, UK, and Canada.



    In fact the two projects didn't get along that well, and as we shall see below, a big part of that was disputes over patents.











    ###







    81



    The following is based on a paper written by Bertrand Goldschmidt, a French nuclear scientist.



    Two of his colleagues, Hans Halban and Lew Kowarski played a critical role in early nuclear research.



    Halban in particular was one of the greatest scientific names in nuclear fission.



    In March of 1939 Halban conducted an experiment showing that neutrons were emitted by the fissioning of uranium.







    82



    In April Joliot, Halban, Kowarski and Perrin had a pretty good idea of how to use nuclear fission to produce energy and to make an explosive device and decided to file patents on their invention. Each of the four would receive a 5% share of any benefits and the other 80% would go to the research instittute they worked at in Paris.







    I will now quote from Goldschmidt's paper.







    83



    The first two patents concerned energy production and were entitled "Device for energy production" and "Method for stabilizing a device for energy production." They roughly defined the principles of the main components of our present power reactors: moderator in heterogeneous or homogeneous arrangements, cooling fluid, control rods, protection shield. The third patent called "Method for perfecting explosive charges" was less brilliant from a foresight point of view though it proposed valid solutions for the trigger, the tamper, and the rapid obtainment of the critical assembly of a possible explosive device. Finally, nearly a year later, after Alfred Nier's experimental confirmation in March 1940 of Niels Bohr's theoretical prediction that uranium 235, the rare isotope of the mixture in natural uranium, was responsible for fission by slow neutrons, the French took out an additional patent on the advantage of using enriched uranium for the chain reaction.







    End of quote.







    84



    In May of 1940, the CNRS, the French research institute in Paris, negotiated an agreement with Belgian mining company Union Miniere, who were the world's biggest producer of uranium, at the time a byproduct of radium mining, about a partnership for the world wide exploitation of these patents. However the agreement was not finalized due to the ongoing events in the war.







    At the beginning of the war, the French government had approved the development of an energy generator - or a nuclear reactor as we would say today, with the intention of creating an engine for submarines.







    85



    With the fall of France, Halban and Kowarski travelled to the UK with their supply of heavy water where they were received by their UK counterparts, James Chadwick and John Cockroft. The British were already working on an atomic bomb.







    In the UK the two conducted an experiment showing that it was possible to create nuclear energy using natural uranium and heavy water.







    In 1941 the British nuclear project was reorganized and given the name Tube Alloys. In 1942 it was decided to move the work on a plutonium bomb to Canada, and Canada would pay for the project. A lab was set up in Montreal and Halban was put in charge of the project.







    86



    Halban had negotiated this arrangement by offering to arrange to have the French patents for world wide rights outside of France and the French empire transferred to the UK. In return the French team were to be given a key role in the British nuclear project.







    The author of the paper I am referencing, Bertrand Goldschmidt, was a section leader in Montreal and a colleague of Halban from France.







    The Montreal group cooperated with the American Manhattan Project and the two shared information and exchanged visits.







    87



    However, relations between the two began to break down, with a major cause of this being the Americans being unhappy about the French patents and Halban's arrangement to give the British world wide rights to them. The postwar commercial potential for nuclear power was seen to be huge, and this was a major bone of contention. The extensive participation of ICI (Imperial Chemical Industries) engineers in the Tube Alloys project was also objectionable to the Americans. Presumably this had something to do with potential for ICI being involved in future commercialization of the technology. The American Dupont company, a commercial rival of ICI, was also heavily involved in the American atomic bomb project. The eventual result of this was that the US cut off cooperation with the UK-Canada nuclear project.







    88



    Finally Halban was forced out of the project at the insistence of the Americans, and he was replaced by John Cockroft who moved to Montreal to take charge of the project. The Americans now restore limited cooperation.







    Kowarski was put in charge of building a heavy water moderated natural uranium reactor at a new site north of Ottawa at Chalk River. This reactor was turned on on the 5th of September, 1945, three days after Japan's surrender.







    So in what was supposedly a titanic war for survival, key allies were falling out with respect to their ultimate weapon over issues of patents covering post war commercialization.







    89



    With the end of the war, the nuclear weapons project in Montreal and Chalk River was wound up.



    Halban, Kowarski, and Goldschmidt returned to France and Cockroft to the UK where they all played senior roles in the nuclear programs of their respective countries.



    John Cockroft played an important role in the development of the Magnox reactors which Antoine asked about.



    The Chalk River Site remains as Canada's main nuclear research centre to this day, and Canada was to continue development of heavy water moderated natural uranium reactors.







    90



    The first commercial nuclear power plant was commissioned in the UK in 1956, roughly 17 years after the original French nuclear patents.



    At that time, UK patents had a term of 16 years.



    While I am not a patent lawyer, it would appear that these patents would likely have expired before nuclear power was ever commercialized.







    So to answer the question about patents, the first patents on nuclear energy date to before WWII started, and the very first two were about nuclear power plants and it was only the third one which covered nuclear weapons.







    --------------------







    91 Thanks to other listeners.







    A number of other listeners made comments saying they were really enjoying the series. I would like to thank the following for their kind words of encouragement. They helped make the work required to do this worthwhile.







    They are







    brian-in-ohio



    mnw



    Clinton



    Antoine



    bjb



    Kevin O'Brien



    Trey



    L'andrew



    Archer72



    Jim DeVore







    If you have commented but I have forgotten your name, or if the show was recorded before I got a chance to read your comment, I would still like to thank you.











    92 Conclusion







    I would like to thank all the listeners for their kind comments and insightful questions.



    I hope that I have answered these questions to the satisfaction of everyone.



    I look forward to hearing from all of you in future podcast episodes including those on other topics.







    --------------------











    Proceedings of the 29th annual conference of the Canadian Nuclear Association and 10th annual conference of the Canadian Nuclear Society. V. 1-3



    https://inis.iaea.org/records/m2s41-40917



    This has a paper by Bertrand Goldschmidt about the work of the French scientists in Canada.











    --------------------





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  • Hacker Public Radio

    HPR4627: UNIX Curio #5 - Faster, Pussycat! Kill! Kill!

    28/04/2026
    This show has been flagged as Clean by the host.

    This series is dedicated to exploring little-known—and occasionally useful—trinkets lurking in the dusty corners of UNIX-like operating systems.


    Let me start by admitting that I've never actually seen the film referenced in the episode title, but I couldn't resist using it anyway.



    If you've used the UNIX command line to any extent, chances are good that you are familiar with the
    kill
    command. A common use is to terminate a misbehaving program. But there is more behind how
    kill
    works, including a curio you might not know about.



    The
    kill
    utility works by sending a "signal" to the targeted process. This signal is selected from a pre-defined list, and triggers the process to interrupt its normal flow and handle the signal before potentially returning back to its work. This "signal handler" can do whatever activities are written in its code, but typically it will take actions connected to the purpose of the specific signal received.



    One option is for the process not to have a signal handler at all; in that case, there is a default action that the operating system will take on behalf of the process, depending on what the signal is. The possible default actions are to terminate the process, take some implementation-defined action (usually writing a core file to disk) and then terminate the process, stop (pause) execution of the process, continue execution of a stopped process, or ignore the signal.



    By default,
    kill
    sends the TERM signal to the process, an indicator that it should terminate. Each signal has a name and a number assigned to it; SIGTERM is the name of the "terminate" signal. You can use the
    -s
    option with the name to choose which signal to send. The 'kill' command is specified to take these names without the SIG prefix, though some implementations will accept them either way. Also,
    kill
    is supposed to be case-insensitive when it comes to these names, but the convention is to write them in all upper case. The assigned numbers for signals can vary depending on the operating system, and on Linux, depending on what processor architecture you're on. However, there is a
    short list of signals


    1
    that have a stable number assigned to them. Despite this, I recommend using the signal name in your scripts to make them clearer and to ensure maximum portability to different systems.



    Well-behaved programs will have a signal handler that responds to the TERM signal by stopping what they are doing, cleaning up any open resources like temporary files, and promptly exiting. However, not every program behaves well, so sometimes it becomes necessary to send them the KILL signal. This one is special and
    cannot be handled or ignored by the program


    2
    ; the operating system will immediately terminate the program, possibly leaving a mess behind.



    Two other signals that can come in handy sometimes are STOP and CONT. As you might expect, STOP forces a process to pause in the middle of whatever it was doing. Its counterpart, CONT (short for "continue"), causes it to resume execution. This can be useful if a program consumes CPU time when not actually doing anything worthwhile—sending it the STOP signal will end that, and when you're ready to use it again, CONT will cause it to pick up right where it left off. Like the KILL signal, STOP cannot be handled or ignored by the program. I have used this to pause the game FreeCiv when I wanted to break away to do something else, but didn't want to have to deal with exiting my current game and having to reload it later. Take note, though, that the program might get confused if it expects the system clock not to suddenly jump forward, as that is exactly how the situation will appear to it. Network connections or other resources the process is using that change while it is stopped are other potential trouble spots. Also be aware that a stopped graphical program will not update its window, so I find it best to minimize the window before stopping it and then continuing the process before trying to raise the window again.



    Programs are not necessarily
    required
    to interpret signals in the way they are described. For example, the HUP signal was originally intended to be sent when a modem or serial connection hang-up occurred. Today, some daemons use it for other purposes and take a specific action in response. For example, the
    Apache web server will restart


    3
    , and
    NetworkManager will reload its configuration


    4
    . These uses of signals are usually described in the daemon's manual page, often in a separate section dedicated to signals.



    While all this background might be interesting (or maybe not), it's pretty commonly known, so isn't really a curio. Our UNIX Curio for today is the "0" signal. This is actually not a signal at all; instead, it tells the
    kill
    utility to just check for the existence of a process. If the process exists,
    kill
    will exit with a status of 0. If it doesn't exist, the exit status will be greater than 0. This provides a handy way to check whether a particular process is still around. A shell command can use this exit status with its control structures like
    if
    to take a particular action depending on whether a particular process exists. Somewhat oddly, "0" is both the number
    and
    the name of this pseudo-signal.



    Why would you want to do this? I have used it for a script to analyze log files that runs daily on a web server. Depending on how much traffic the site is getting, the log files can grow to the point where it takes longer than a day for the script to get through them. If a second instance of the script is started while one is still running, it will slow down both and if more keep being added, eventually the machine will run out of memory.



    My solution was to create a .pid file containing the process ID number of the running script. You might see examples of these if you look in /run or /var/run on your system. The script creates a file named something like "myscript.pid" in this directory containing its own process ID, which can be accessed in the shell with the variable
    $$
    . When my script starts, it checks to see whether this file exists. If so, it uses
    kill -s 0 $(cat /run/myscript.pid)
    to see if the previous process still exists. If the process is no longer around, that's a sign that it exited abnormally before it had the chance to delete the .pid file, so the script removes the abandoned .pid file, replaces it with a new one containing the current process ID, and continues with its work. If the previous process is still around, my script exits with a message to that effect. This way, I can be sure that only one instance of the script will ever be running at one time.



    Be aware that the
    kill
    utility might also return a non-zero exit status if the user running it does not have privileges to send a signal to the process with the specified ID. This is not a concern if you are running a script as the root user, but could be if you are not. This can occur even if you aren't actually sending a signal, just using the "0" pseudo-signal to check if a process exists.



    There
    is
    a weakness in this method. UNIX-like systems generally have a limit to the quantity of process ID numbers that can be issued, so they are reused over time. (However, there will never be two processes with the same ID number running at the
    same
    time.) Typically, the first process that is run on start-up will be given the ID number 1, and each subsequent process will get the next higher number. Once the maximum is reached, the system starts again at the beginning with the lowest number not in use. It is possible for the script to crash and leave behind the .pid file, then the same process ID could be recycled and actively used for another program, causing a new instance of the script to give up. The chances of this are small enough that for my purposes, it's not worth worrying about. But you should be aware that it could happen.



    I should also note that it's not strictly necessary to use
    kill
    for the purpose I described. The
    ps
    utility can also be given a process ID with the
    -p
    option; if the process exists, the exit status will be 0, otherwise it will be greater than 0. In this case, you could also use the output to check that the name of the command matches what you expect, helping avoid the problem of a recycled process ID. In addition,
    ps
    doesn't concern itself with permissions for sending signals, so it will report on the existence of a process no matter what user you are running it as. From an efficiency standpoint,
    kill
    generally requires fewer resources to run (in fact, it is built in to some shells), but functionally
    ps
    can also do the job.



    So keep in mind that
    kill
    is capable of doing more than just killing off programs—maybe you can put it to one of these uses for your needs.



    References:







    Kill specification
    https://pubs.opengroup.org/onlinepubs/009695399/utilities/kill.html





    signal.h specification
    https://pubs.opengroup.org/onlinepubs/009695399/basedefs/signal.h.html





    Stopping and Restarting Apache HTTP Server
    https://httpd.apache.org/docs/2.4/stopping.html#hup





    NetworkManager: Signals
    https://networkmanager.dev/docs/api/latest/NetworkManager.html#id-1.2.2.9







    Appendix 1
    - example script:



    #!/bin/sh

    # Use your own unique name here - be sure you can write to this location
    pidfile="/var/run/myscript.pid"

    # Exit if previous run hasn't completed yet
    if [ -f "$pidfile" ] ; then
    oldpid=$(cat "$pidfile")
    if kill -s 0 $oldpid ; then
    echo "${0}: Not running script, older process $oldpid still active"
    exit 1
    else
    echo "${0}: Removing old pidfile from nonexistent process $oldpid"
    rm -f "$pidfile"
    fi
    fi

    # Create pidfile
    echo $$ > "$pidfile"

    ## Insert commands to do the actual work of the script here

    # Remove pidfile
    rm -f "$pidfile"





    Appendix 2
    - another version of the script using
    ps
    instead of
    kill
    , checking that an existing process ID is actually the same command, and with extra validation of the contents of the pidfile; perhaps better for use by a non-root user:



    #!/bin/sh

    # Use your own unique name here - be sure you can write to this location
    pidfile="$HOME/myscript.pid"

    # Exit if previous run hasn't completed yet
    if [ -f "$pidfile" ] ; then
    oldpid=$(( 1 * $(cat "$pidfile") ))
    if [ -n "$oldpid" ] && [ "$oldpid" -gt 1 ] ; then
    :
    else
    echo "${0}: Not running script, $pidfile contents invalid"
    exit 1
    fi
    # Test if old process ID exists
    if oldcmd="$( ps -o comm= -p $oldpid )" &&
    # Also test if command name of old process is same as current script
    [ "$oldcmd" = "${0##*/}" ] ; then
    echo "${0}: Not running script, older process $oldpid still active"
    exit 1
    else
    echo "${0}: Removing old pidfile from nonexistent process $oldpid"
    rm -f "$pidfile"
    fi
    fi

    # Create pidfile
    echo $$ > "$pidfile"

    ## Insert commands to do the actual work of the script here

    # Remove pidfile
    rm -f "$pidfile"





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  • Hacker Public Radio

    HPR4626: Cable Management / PC Speakers

    27/04/2026
    This show has been flagged as Explicit by the host.


    Cable Management / PC Speakers ...








    Boao 3 Pieces Cord Protector Wire Loom Black Tubing Cable Sleeve Split Sleeving for USB Charger Cord Cover Audio Video Cable, Each Size 10 ft 3/4 Inch, 1/2





    https://www.amazon.com/dp/B08JPV4NRJ









    Split-Sleeve Wire Loom for High-Temperature Automotive Harness and Home Cable Management, 25ft - 1/2 inch Braided Cable Management Sleeve Cord Protector, Self-Wrapping Split Wire Loom





    https://www.amazon.com/dp/B0C4LD8FP3

























    PreSonus Eris 3.5 Studio Monitors, Pair — Powered, Active Monitor Speakers for Near Field Music Production, Desktop Computer, Hi-Fi Audio





    https://www.amazon.com/dp/B0C88ZB3D9













    Wood Hangboard Rock Climbing Holds - Sturdy Hang Board for Climbers





    https://www.amazon.com/dp/B07X58S696









    POWER GUIDANCE Hangboard Rock Climbing Holds Finger Strengthener for Pull-up Grip Arm Training Indoor and Outdoor Double-Sided Non-Slip Portable





    https://www.amazon.com/dp/B09VTG6RZN









    Cosmos 1 Pc Green Screen Backdrop 43 in / 110 cm Diameter Foldable Portable Photography Background Green Screen Chroma Key Backdrop for Photography Photo Video Studio, Live Streaming, Video Meeting









    https://www.amazon.com/dp/B0CQNRWL7K




























    Key Points:












    New Monitor Setup:




    Ordered a new 49-inch curved monitor.



    Current setup involves a steering wheel that needs to be moved for gaming and work.



    Detailed process for switching between gaming and work modes.









    Cable Management:




    Discussed different brands of wire loom: Boao and teziicus Store .



    BOA is cheaper and see-through, while teziicus Store is more expensive but better quality.



    Explained the use of split sleeve wire loom for easier cable management.



    Tips on using heat shrink tubing and a heat gun for a better seal.



    Mentioned using Gorilla Glue for expanding and sealing large dongles.



    Recommended sizes for wire loom: three-fourths inch for larger cables, one-fourth inch for smaller cables.









    Labeling and Organization:




    Emphasized the importance of labeling cables using a label maker.



    Suggested using specific tape for patch cables and placing labels a few inches away from the plug for easy identification.



    Mentioned using twist ties for temporary cable management and Velcro for more permanent setups.









    Additional Tools and Tips:




    Used binder clips and paracord for temporary setups.



    Mentioned using power guide holds for rock climbing practice during calls.



    Discussed the potential for a dual monitor setup to avoid moving the monitor frequently.









    PC Speakers:




    Noted the shift from traditional PC speakers to studio speakers.



    Mentioned entry-level studio speakers costing around $99.



    Highlighted the need for a subwoofer for better bass.



    Discussed bass shakers for haptic feedback in racing games.









    Workspace Cleanliness:




    Emphasized the importance of keeping the workspace clean and organized.



    Mentioned using a green screen for video calls, hung from the ceiling for a flat surface.











    Conclusion:










    Encouraged listeners to keep their workspaces clean and organized for better productivity and aesthetics.



    Provided practical tips and tools for effective cable management and workspace setup.







    Closing Remarks:










    Wished listeners a good day and encouraged them to record their own episodes.







    Additional Notes:










    Mentioned the use of a standing desk and the challenges of dual-use with a steering wheel setup.



    Discussed the potential for a separate office table for gaming and work to avoid frequent adjustments.







    Host's Personal Note:










    Acknowledged the change in format for better show notes and clarity for listeners.















    Provide feedback on this episode.
  • Hacker Public Radio

    HPR4625: Site Specific Browsers

    24/04/2026
    This show has been flagged as Clean by the host.



    A progressive web application (PWA), or progressive web app, is a type of web app that can be installed on a device as a standalone application. PWAs are installed using the offline cache of the device's web browser.








    PWAs were introduced from 2016 as an alternative to native (device-specific) applications, with the advantage that they do not require separate bundling or distribution for different platforms. They can be used on a range of different systems, including desktop and mobile devices. Publishing the app to digital distribution systems, such as the Apple App Store, Google Play, or the Microsoft Store on Windows, is optional.










    -- Wikipedia.org





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