This article proposes to associate a Deuterium-Deuterium (D-D) fusion reactor with a PWR (fission Pressurized Water Reactor) in a hybrid reactor. Even if the mechanical gain (Q factor) of the D-D fusion reactor is bel...This article proposes to associate a Deuterium-Deuterium (D-D) fusion reactor with a PWR (fission Pressurized Water Reactor) in a hybrid reactor. Even if the mechanical gain (Q factor) of the D-D fusion reactor is below the unity and consequently consumes more energy than it supplies, due to the high energy amplification factor of the PWR fission reactor, the global yield is widely superior to 1. As the energy supplied by the fusion reactor is relatively low and as the neutrons supplied are mainly issued from D-D fusions (at 2.45 MeV), the problems of heat flux and neutrons damage connected with materials, as with D-T fusion reactors are reduced. Of course, there is no need to produce Tritium with this D-D fusion reactor. This type of reactor is able to incinerate any mixture of natural Uranium, natural Thorium and depleted Uranium (waste issued from enrichment plants), with natural Thorium being the best choice. No enriched fuel is needed. So, this type of reactor could constitute a source of energy for several thousands of years because it is about 90 more efficient than a standard fission reactor, such as a PWR or a Candu one, by extracting almost completely the energy from the fertile materials U238 and Th232. For the fission part, PWR technology is mature. For the fusion part, it is based on a reasonable hypothesis done on present Stellarators projects. The working of this reactor is continuous, 24 hours a day. In this paper, it will be targeted a reactor able to provide net electric power of about 1400 MWe, as a big fission power plant.展开更多
Big Bang nucleosynthesis(BBN)theory predicts the primordial abundances of the light elements^(2) H(referred to as deuterium,or D for short),^(3)He,^(4)He,and^(7) Li produced in the early universe.Among these,deuterium...Big Bang nucleosynthesis(BBN)theory predicts the primordial abundances of the light elements^(2) H(referred to as deuterium,or D for short),^(3)He,^(4)He,and^(7) Li produced in the early universe.Among these,deuterium,the first nuclide produced by BBN,is a key primordial material for subsequent reactions.To date,the uncertainty in predicted deuterium abundance(D/H)remains larger than the observational precision.In this study,the Monte Carlo simulation code PRIMAT was used to investigate the sensitivity of 11 important BBN reactions to deuterium abundance.We found that the reaction rate uncertainties of the four reactions d(d,n)^(3)He,d(d,p)t,d(p,γ)^(3)He,and p(n,γ)d had the largest influence on the calculated D/H uncertainty.Currently,the calculated D/H uncertainty cannot reach observational precision even with the recent LUNA precise d(p,γ)^(3) He rate.From the nuclear physics aspect,there is still room to largely reduce the reaction-rate uncertainties;hence,further measurements of the important reactions involved in BBN are still necessary.A photodisintegration experiment will be conducted at the Shanghai Laser Electron Gamma Source Facility to precisely study the deuterium production reaction of p(n,γ)d.展开更多
A double-well potential model is proposed for the pionic deuterium that enables to calculate the energy split, the potential barrier height and estimate the pion tetrahedron edge length. We propose that pion tetrahedr...A double-well potential model is proposed for the pionic deuterium that enables to calculate the energy split, the potential barrier height and estimate the pion tetrahedron edge length. We propose that pion tetrahedrons, π<sup>Td</sup> = u<sub>d</sub>~</sup>dũ, play a central role in the Yukawa interaction by enabling quark exchange reactions between protons and neutrons by tunneling through a potential barrier. A vacuum polarization Feynman diagram is proposed for the π<sup>Td</sup> having chains of fermion loops for the two valence quarks and anti-quarks connected by gluons. With a higher order vacuum polarization diagram, the d and u quark loops are interleaved and the chiral symmetry is broken dynamically. The proposed π<sup>Td</sup> vacuum polarization integral does not diverge in both the IR and UV limits and vanishes in the limit of an infinite pion tetrahedron condensate. We propose a new Delbruck scattering Feynman diagram that includes d and u quark and anti-quark interleaved loops. We further propose that conversion of gravitons to photons may occur via quark and anti-quark loops that describe the pion tetrahedrons dynamics in the vacuum and may also transfer gravitational waves.展开更多
This article looks for the necessary conditions to use Deuterium-Deuterium (D-D) fusion for a large power plant. At the moment, for nearly all the projects (JET, ITER…) only the Deuterium-Tritium (D-T) fuel is consid...This article looks for the necessary conditions to use Deuterium-Deuterium (D-D) fusion for a large power plant. At the moment, for nearly all the projects (JET, ITER…) only the Deuterium-Tritium (D-T) fuel is considered for a power plant. However, as shown in this article, even if a D-D reactor would be necessarily much bigger than a D-T reactor due to the much weaker fusion reactivity of the D-D fusion compared to the D-T fusion, a D-D reactor size would remain under an acceptable size. Indeed, a D-D power plant would be necessarily large and powerful, i.e. the net electric power would be equal to a minimum of 1.2 GWe and preferably above 10 GWe. A D-D reactor would be less complex than a D-T reactor as it is not necessary to obtain Tritium from the reactor itself. It is proposed the same type of reactor yet proposed by the author in a previous article, i.e. a Stellarator “racetrack” magnetic loop. The working of this reactor is continuous. It is reminded that the Deuterium is relatively abundant on the sea water, and so it constitutes an almost inexhaustible source of energy. Thanks to secondary fusions (D-T and D-He3) which both occur at an appreciable level above 100 keV, plasma can stabilize around such high equilibrium energy (i.e. between 100 and 150 keV). The mechanical gain (Q) of such reactor increases with the internal pipe radius, up to 4.5 m. A radius of 4.5 m permits a mechanical gain (Q) of about 17 which thanks to a modern thermo-dynamical conversion would lead to convert about 21% of the thermal power issued from the D-D reactor in a net electric power of 20 GWe. The goal of the article is to create a physical model of the D-D reactor so as to estimate this one without the need of a simulator and finally to estimate the dimensions, power and yield of such D-D reactor for different net electrical powers. The difficulties of the modeling of such reactor are listed in this article and would certainly be applicable to a future D-He3 reactor, if any.展开更多
An efficient procedure for the synthesis of agmatine labelled with tritium and deuterium is reported. The final tritiated product 4 was obtained with a specific activity of 40 Ci/mmol and a radiochemical purity of 95%.
Deuterium-depleted water (DDW) is a new promising agent in cancer therapy. The efficiency of the method is based on the discovery, that cancer cells are extremely sensitive to depletion of deuterium (D) and might caus...Deuterium-depleted water (DDW) is a new promising agent in cancer therapy. The efficiency of the method is based on the discovery, that cancer cells are extremely sensitive to depletion of deuterium (D) and might cause necrosis of the tumour. The purpose of this study was to show the efficacy of D-depletion in prostate cancer (PC) patients. In the double blind, four-month-long, randomized Phase II clinical trial the daily water intake was replaced with DDW in 22 PC patients. Other 22 PC patients took normal water while both groups received the same forms of conventional treatment. In the retrospective study, 91 DDW-treated PC patients were evaluated and median survival time (MST) in the subgroups was calculated. The time course of changes in DDW dose and PSA is presented in two cases. In the prospective trial seven patients in the treated group and one patient in the placebo group achieved partial response (p = 0.046). In the treated group, the net decrease in the prostate volume was three times higher (160.3 cm3 vs. 54.0 cm3;p = 0.0019), urination complaints ceased at a higher rate (8 vs. 0 patients, p = 0.0041), and the one-year survival rate was also higher (2 vs. 9 deaths;p = 0.034). The 91 retrospectively evaluated patients achieved an MST of 11.02 years, despite the fact that 46 of them suffered from distant metastasis. In the two monitored patients, drop of PSA level correlated with the DDW intake. In summary, D-depletion prolonged MST in patients with PC. The method proved to be safe thus its integration in the PC cure as an adjuvant or complementary therapy would be considered.展开更多
The positron lifetime spectroscopy was used to investigate the electron structures of crystal lattice and its defects in palladium samples filled galvanostatically with hydrogen and deuterium, respectively. The result...The positron lifetime spectroscopy was used to investigate the electron structures of crystal lattice and its defects in palladium samples filled galvanostatically with hydrogen and deuterium, respectively. The results have indicated that the positron lifetime were all the same between hydrogen and deuterium filled samples in which the positron lifetime τ(?) increased about 10%, corresponding to the volume expansibility after the formation of hydrides PdH or PdD phases during electrolyzing commom water or heavy water with Pd cathode; and Will not change with time in 3 weeks after stopping electrolysis; but could be recovered to 116±1ps, the value in polycrystalline pure palladium, after annealing at high temperature.展开更多
Based on neon gas puffing, an active feedback control of H-mod plasma divertor detachment experiment was successfully operated on the EAST tokamak. During the feedback control discharge, the plasma was detached by puf...Based on neon gas puffing, an active feedback control of H-mod plasma divertor detachment experiment was successfully operated on the EAST tokamak. During the feedback control discharge, the plasma was detached by puffing neon gas and the strike point splitting phenomenon on divertor target was also clearly observed by divertor probes diagnostic.In boundary region, many neutral particle processes(atom and molecule) were happened and accompanied by their emission spectra under the detachment discharge. By studying these emission spectra, it is helpful for us to understand the role of atoms and molecules in boundary recycling, which is important for studying the physical mechanism of divertor detachment. For the Fulcher-α system(d(3 p)3Πu±→ a(2 s)3Σg+), D2 emission spectra in the range from 601 nm to 606 nm were observed, identified and fitted in the detachment experiment for the first time on the EAST, and the spectra in the Q(0–0) band(d3Πu-→ a(2 s)3Σg+) in the Q branch of the Fulcher-α system were used for detailed analysis to acquire the boundary region temperature Te(below 5eV), which could not be provided very well by other diagnostics on the EAST. An electronic version deuterium molecular spectral line database was established to identify the spectral lines and a multi-peak fitting program was developed to fit and analyze the observed spectra.展开更多
Large deuterium clusters are generated using a cryogenic pulse valve with a cone nozzle (21 mm long, 4° open angle). Rayleigh scattering experiment is carried out to obtain the scaling relation between scatteri...Large deuterium clusters are generated using a cryogenic pulse valve with a cone nozzle (21 mm long, 4° open angle). Rayleigh scattering experiment is carried out to obtain the scaling relation between scattering signal SR and backing pressure P0. A method using the Coulomb explosion model is proposed to verify that the clusters continue to grow after their leaving the nozzle. Our experiments suggest a tentatively optimized position for laser cluster interaction.展开更多
Fuel retention and recycling in plasma facing materials is a crucial issue for fusion devices, especially for the long pulse discharge devices. In this work, the deuterium retention and the surface erosion of SiC-coat...Fuel retention and recycling in plasma facing materials is a crucial issue for fusion devices, especially for the long pulse discharge devices. In this work, the deuterium retention and the surface erosion of SiC-coated graphite tiles exposed to EAST plasmas have been studied by post-mortem analyses, i.e., thermal desorption spectroscopy (TDS), secondary ion mass spec- troscopy (SIMS) and scanning electron microscopy (SEM). The results show that the sample cut from the high field side (HF) tile has been intensely eroded due to deuterium bombardment on plasma facing surfaces in the initial phase of discharges and trapped highest amount of deuterium. Lower deuterium retention has been found in the inner divertor sample, which is presumably due to the particular exposure history in the 2010 spring campaign.展开更多
The present paper deals with the induced orientational order of the probe molecules dissolved in the uniaxially strained rubbers measured by using deuterium NMR. The distinctive dependence of the quadrupolar splitting...The present paper deals with the induced orientational order of the probe molecules dissolved in the uniaxially strained rubbers measured by using deuterium NMR. The distinctive dependence of the quadrupolar splitting on the swelling, elongation and crosslinking density was observed. The orientational order arising from the correlation between chain segments decreases with the increase of the numbers of both links between junctions and solvent molecules around segments.展开更多
There is still very little information on the sources of water absorbed by oil palm plant. This information is very important for water management system in oil palm plantation. Thus, this study was carried out to det...There is still very little information on the sources of water absorbed by oil palm plant. This information is very important for water management system in oil palm plantation. Thus, this study was carried out to determine current water sources absorbed by the oil palm roots using oxygen (δ18O) and deuterium isotopes (δD) techniques. Sketches of oxygen and deuterium isotope were total rainfall, throughfall, runoff, measurement at 5 soil depths (namely: 20 cm, 50 cm, 100 cm, 150 cm, and 200 cm), and oil palm stem. Results of this study showed huge variance in the values of oxygen and deuterium isotope. Based on Least Significant Difference (LSD) test, there was no significant value in the oxygen and deuterium isotope of stem water and others;however, a similar value was obtained at the depths of 0 - 20 cm and 20 - 50 cm with the stem water. This indicated that oil palm absorbed water from 0 - 50 cm depth. This result agreed with the oil palm rooting system, which has verified that the root quarter is the most active root of oil palm.展开更多
Deuterium isotope effects in the CO2-reforming of methane to syngas were firstinvestigated over SiO2-supported rhodium catalysts. Normal deuterium isotop effect was morenoticeable on the methane conversion reaction t...Deuterium isotope effects in the CO2-reforming of methane to syngas were firstinvestigated over SiO2-supported rhodium catalysts. Normal deuterium isotop effect was morenoticeable on the methane conversion reaction than on the CO formation reaction, while there wasno such effect on the CO2 conversion reaction. It can be concluded that the dissociation of the C-Hbond in methane is a key mp and some CO is formed by the reverse water-gas shift reaction.展开更多
After 290 h electrochemical charging of deuterium,the density of dislocation in well-annealed Pd was increased from 10~8/cm^2 to over 10~12/cm^2 and a large amount of bubble-like voids or cracks was observed by optica...After 290 h electrochemical charging of deuterium,the density of dislocation in well-annealed Pd was increased from 10~8/cm^2 to over 10~12/cm^2 and a large amount of bubble-like voids or cracks was observed by optical and transmission electron microscopes.The mechanism of deuterium cracking is believed due to the formation of molecular De during the segregstion and combination of deuterium atoms around dislocations.XRD results showed that the lattice constant of Pd increased from 0.3890 nm to 0.4034 nm.展开更多
This article explores a technique for measuring the energy (NEL) value of feeds without respiration calorimetry or slaughter. The objectives were to compare results obtained from goats with those from cows, and to des...This article explores a technique for measuring the energy (NEL) value of feeds without respiration calorimetry or slaughter. The objectives were to compare results obtained from goats with those from cows, and to describe factors which limited the precision of these NEL estimates. One lactating Alpine doe and one lactateing Holstein cow were assigned to each of six different sequences of three 56-d feeding treatments consisting of low, medium, and high doses of the basal diet, rice bran, or hominy feed. This resulted in 30 observations of the basal diet and 12 of each byproduct feed for each species and utilized a total of 18 cows and 18 does. The NEL values of the basal diet, rice bran, and hominy feed were calculated as the sum of milk energy, change in body energy, and estimated fasting heat production per kilogram of feed dry matter. Milk energy was determined by bomb calorimetry and body energy from live body weight and deuterium oxide space. The NEL (MJ/kg) determined in this manner were basal diet, 5.73 and 5.98;rice bran, 7.11 and 7.07;and hominy feed, 6.99 and 8.20 for cows and goats, respectively.展开更多
Stable neutron generation with a yield of ~1.2×10^(4) neutrons per pulse was obtained during d(d,n)^(3)He reaction initiated by the high-voltage nanosecond discharge in a gap with a potential tungsten cylinder(an...Stable neutron generation with a yield of ~1.2×10^(4) neutrons per pulse was obtained during d(d,n)^(3)He reaction initiated by the high-voltage nanosecond discharge in a gap with a potential tungsten cylinder(anode)and a grounded deuterated zirconium plate(cathode)filled with deuterium at a pressure of ~10^(2) Pa.Estimated duration of the neutron pulse was ~1.5 ns.Less intensive neutron emission was registered without deuterated plate.Splashing of material of the tungsten electrode was observed during the high-voltage nanosecond discharge in the deuterium,hydrogen,helium and argon at pressures of 10^(2)-10^(4) Pa.展开更多
D+2 ions of 70 and 90 keV were separately implanted into two thick samples of sintered alumina ceramic and the distribution of deuterium has been measured for three runs at an interval of 5 months using high energy pr...D+2 ions of 70 and 90 keV were separately implanted into two thick samples of sintered alumina ceramic and the distribution of deuterium has been measured for three runs at an interval of 5 months using high energy proton backscattering and elastic recoil detection (ERD). The measured data show that there is little diffusion of deuterium in A12O3 and the diffusion coefficient is deduced to be 1.1 ×10-17 cm2/s. The measured total concentration of implanted deuterium is 4.5×1018 at./cm2. The profile of hydrogen adsorbed on the surface of Al2O3 samples was also observed by ERD and 1H(19F, αγ)16O analysis. The distribution range of 1H in Al2O3 after deuterium implantation is much larger than that before one.展开更多
Based on our previous work(Phys.Plasmas 25 012704(2018)),a fitting formula is given for electron-ion energy partition fraction of 3.54-MeV fusion alpha particles in deuterium-tritium(DT) plasmas as a function of plasm...Based on our previous work(Phys.Plasmas 25 012704(2018)),a fitting formula is given for electron-ion energy partition fraction of 3.54-MeV fusion alpha particles in deuterium-tritium(DT) plasmas as a function of plasma mass density ρ,electron temperature T_(e),and ion temperature T_(i).The formula can be used in a huge range of the plasma state,where ρ varies between 1.0 g/cc~10.0^(3) g/cc and both T_(e) and T_(i) change from 0.1 keV to 100.0 keV.Relativistic effect for electrons is investigated including the effect of the projectile recoil in the plasmas at T_(e)≥ 50.0 keV.The partition fraction for T_(e)>T_(i) is found to be close to that for T_(e)=T_(i). The comparisons with other fitting results are made at some plasma densities when T_(e)=T_(i),and the difference is explained.The fitting result is very close to the calculated one in most cases,which is convenient for the simulation of alpha heating in hot dense DT plasmas for inertial confined fusion.展开更多
In this study,a Cr_(2)O_(3) nanosheet(Cr_(2)O_(3) NS)inserted Cr-Zr-O coating was developed as a hydrogen isotope permeation barrier.The Cr_(2)O_(3) NSs,fabricated by rapid heat treatment,were amorphous with a thickne...In this study,a Cr_(2)O_(3) nanosheet(Cr_(2)O_(3) NS)inserted Cr-Zr-O coating was developed as a hydrogen isotope permeation barrier.The Cr_(2)O_(3) NSs,fabricated by rapid heat treatment,were amorphous with a thickness of only several nanometers.These Cr_(2)O_(3) NSs were then incorporated into a Cr-Zr-O multi-metal oxide composite coating via a dip-coating method to form a coating.The effect of the Cr_(2)O_(3) NS concentration on the morphology,microstructure and deuterium permeation resistance of the coating was studied.With the addition of 1.0 g 1^(-1)Cr_(2)O_(3) NSs,compared with the Cr-Zr-O coating without NSs,the permeation reduction factor of the resultant coating was enhanced from 249℃to 575℃ at 500℃.The coating,with a thickness of nearly 193 nm,achieved a comparable deuterium resistance that was above two orders of magnitude higher than the steel substrate.The results show that ceramic NSs can serve as effective fillers for enhancing the coating performance when functioning as a hydrogen isotope barrier.展开更多
Mass spectral behavior of some deuterated and non-deuterated substituted benzylglyoxals was characteristic in enolic structure which was also proved by NMR spectrum. Fragmentation of the title compounds in their mass ...Mass spectral behavior of some deuterated and non-deuterated substituted benzylglyoxals was characteristic in enolic structure which was also proved by NMR spectrum. Fragmentation of the title compounds in their mass spectra was ressonably explained in this paper.展开更多
文摘This article proposes to associate a Deuterium-Deuterium (D-D) fusion reactor with a PWR (fission Pressurized Water Reactor) in a hybrid reactor. Even if the mechanical gain (Q factor) of the D-D fusion reactor is below the unity and consequently consumes more energy than it supplies, due to the high energy amplification factor of the PWR fission reactor, the global yield is widely superior to 1. As the energy supplied by the fusion reactor is relatively low and as the neutrons supplied are mainly issued from D-D fusions (at 2.45 MeV), the problems of heat flux and neutrons damage connected with materials, as with D-T fusion reactors are reduced. Of course, there is no need to produce Tritium with this D-D fusion reactor. This type of reactor is able to incinerate any mixture of natural Uranium, natural Thorium and depleted Uranium (waste issued from enrichment plants), with natural Thorium being the best choice. No enriched fuel is needed. So, this type of reactor could constitute a source of energy for several thousands of years because it is about 90 more efficient than a standard fission reactor, such as a PWR or a Candu one, by extracting almost completely the energy from the fertile materials U238 and Th232. For the fission part, PWR technology is mature. For the fusion part, it is based on a reasonable hypothesis done on present Stellarators projects. The working of this reactor is continuous, 24 hours a day. In this paper, it will be targeted a reactor able to provide net electric power of about 1400 MWe, as a big fission power plant.
基金supported by the National Key R&D Program of China(No.2022YFA1602401)by the National Natural Science Foundation of China(No.11825504)。
文摘Big Bang nucleosynthesis(BBN)theory predicts the primordial abundances of the light elements^(2) H(referred to as deuterium,or D for short),^(3)He,^(4)He,and^(7) Li produced in the early universe.Among these,deuterium,the first nuclide produced by BBN,is a key primordial material for subsequent reactions.To date,the uncertainty in predicted deuterium abundance(D/H)remains larger than the observational precision.In this study,the Monte Carlo simulation code PRIMAT was used to investigate the sensitivity of 11 important BBN reactions to deuterium abundance.We found that the reaction rate uncertainties of the four reactions d(d,n)^(3)He,d(d,p)t,d(p,γ)^(3)He,and p(n,γ)d had the largest influence on the calculated D/H uncertainty.Currently,the calculated D/H uncertainty cannot reach observational precision even with the recent LUNA precise d(p,γ)^(3) He rate.From the nuclear physics aspect,there is still room to largely reduce the reaction-rate uncertainties;hence,further measurements of the important reactions involved in BBN are still necessary.A photodisintegration experiment will be conducted at the Shanghai Laser Electron Gamma Source Facility to precisely study the deuterium production reaction of p(n,γ)d.
文摘A double-well potential model is proposed for the pionic deuterium that enables to calculate the energy split, the potential barrier height and estimate the pion tetrahedron edge length. We propose that pion tetrahedrons, π<sup>Td</sup> = u<sub>d</sub>~</sup>dũ, play a central role in the Yukawa interaction by enabling quark exchange reactions between protons and neutrons by tunneling through a potential barrier. A vacuum polarization Feynman diagram is proposed for the π<sup>Td</sup> having chains of fermion loops for the two valence quarks and anti-quarks connected by gluons. With a higher order vacuum polarization diagram, the d and u quark loops are interleaved and the chiral symmetry is broken dynamically. The proposed π<sup>Td</sup> vacuum polarization integral does not diverge in both the IR and UV limits and vanishes in the limit of an infinite pion tetrahedron condensate. We propose a new Delbruck scattering Feynman diagram that includes d and u quark and anti-quark interleaved loops. We further propose that conversion of gravitons to photons may occur via quark and anti-quark loops that describe the pion tetrahedrons dynamics in the vacuum and may also transfer gravitational waves.
文摘This article looks for the necessary conditions to use Deuterium-Deuterium (D-D) fusion for a large power plant. At the moment, for nearly all the projects (JET, ITER…) only the Deuterium-Tritium (D-T) fuel is considered for a power plant. However, as shown in this article, even if a D-D reactor would be necessarily much bigger than a D-T reactor due to the much weaker fusion reactivity of the D-D fusion compared to the D-T fusion, a D-D reactor size would remain under an acceptable size. Indeed, a D-D power plant would be necessarily large and powerful, i.e. the net electric power would be equal to a minimum of 1.2 GWe and preferably above 10 GWe. A D-D reactor would be less complex than a D-T reactor as it is not necessary to obtain Tritium from the reactor itself. It is proposed the same type of reactor yet proposed by the author in a previous article, i.e. a Stellarator “racetrack” magnetic loop. The working of this reactor is continuous. It is reminded that the Deuterium is relatively abundant on the sea water, and so it constitutes an almost inexhaustible source of energy. Thanks to secondary fusions (D-T and D-He3) which both occur at an appreciable level above 100 keV, plasma can stabilize around such high equilibrium energy (i.e. between 100 and 150 keV). The mechanical gain (Q) of such reactor increases with the internal pipe radius, up to 4.5 m. A radius of 4.5 m permits a mechanical gain (Q) of about 17 which thanks to a modern thermo-dynamical conversion would lead to convert about 21% of the thermal power issued from the D-D reactor in a net electric power of 20 GWe. The goal of the article is to create a physical model of the D-D reactor so as to estimate this one without the need of a simulator and finally to estimate the dimensions, power and yield of such D-D reactor for different net electrical powers. The difficulties of the modeling of such reactor are listed in this article and would certainly be applicable to a future D-He3 reactor, if any.
文摘An efficient procedure for the synthesis of agmatine labelled with tritium and deuterium is reported. The final tritiated product 4 was obtained with a specific activity of 40 Ci/mmol and a radiochemical purity of 95%.
文摘Deuterium-depleted water (DDW) is a new promising agent in cancer therapy. The efficiency of the method is based on the discovery, that cancer cells are extremely sensitive to depletion of deuterium (D) and might cause necrosis of the tumour. The purpose of this study was to show the efficacy of D-depletion in prostate cancer (PC) patients. In the double blind, four-month-long, randomized Phase II clinical trial the daily water intake was replaced with DDW in 22 PC patients. Other 22 PC patients took normal water while both groups received the same forms of conventional treatment. In the retrospective study, 91 DDW-treated PC patients were evaluated and median survival time (MST) in the subgroups was calculated. The time course of changes in DDW dose and PSA is presented in two cases. In the prospective trial seven patients in the treated group and one patient in the placebo group achieved partial response (p = 0.046). In the treated group, the net decrease in the prostate volume was three times higher (160.3 cm3 vs. 54.0 cm3;p = 0.0019), urination complaints ceased at a higher rate (8 vs. 0 patients, p = 0.0041), and the one-year survival rate was also higher (2 vs. 9 deaths;p = 0.034). The 91 retrospectively evaluated patients achieved an MST of 11.02 years, despite the fact that 46 of them suffered from distant metastasis. In the two monitored patients, drop of PSA level correlated with the DDW intake. In summary, D-depletion prolonged MST in patients with PC. The method proved to be safe thus its integration in the PC cure as an adjuvant or complementary therapy would be considered.
文摘The positron lifetime spectroscopy was used to investigate the electron structures of crystal lattice and its defects in palladium samples filled galvanostatically with hydrogen and deuterium, respectively. The results have indicated that the positron lifetime were all the same between hydrogen and deuterium filled samples in which the positron lifetime τ(?) increased about 10%, corresponding to the volume expansibility after the formation of hydrides PdH or PdD phases during electrolyzing commom water or heavy water with Pd cathode; and Will not change with time in 3 weeks after stopping electrolysis; but could be recovered to 116±1ps, the value in polycrystalline pure palladium, after annealing at high temperature.
基金Project supported by the National Natural Science Foundation of China(Grant No.11805234)
文摘Based on neon gas puffing, an active feedback control of H-mod plasma divertor detachment experiment was successfully operated on the EAST tokamak. During the feedback control discharge, the plasma was detached by puffing neon gas and the strike point splitting phenomenon on divertor target was also clearly observed by divertor probes diagnostic.In boundary region, many neutral particle processes(atom and molecule) were happened and accompanied by their emission spectra under the detachment discharge. By studying these emission spectra, it is helpful for us to understand the role of atoms and molecules in boundary recycling, which is important for studying the physical mechanism of divertor detachment. For the Fulcher-α system(d(3 p)3Πu±→ a(2 s)3Σg+), D2 emission spectra in the range from 601 nm to 606 nm were observed, identified and fitted in the detachment experiment for the first time on the EAST, and the spectra in the Q(0–0) band(d3Πu-→ a(2 s)3Σg+) in the Q branch of the Fulcher-α system were used for detailed analysis to acquire the boundary region temperature Te(below 5eV), which could not be provided very well by other diagnostics on the EAST. An electronic version deuterium molecular spectral line database was established to identify the spectral lines and a multi-peak fitting program was developed to fit and analyze the observed spectra.
基金Project supported by the National Natural Science Foundation of China (Grant No. 10975121)the Foundation of National Key Laboratory of Laser Plasma
文摘Large deuterium clusters are generated using a cryogenic pulse valve with a cone nozzle (21 mm long, 4° open angle). Rayleigh scattering experiment is carried out to obtain the scaling relation between scattering signal SR and backing pressure P0. A method using the Coulomb explosion model is proposed to verify that the clusters continue to grow after their leaving the nozzle. Our experiments suggest a tentatively optimized position for laser cluster interaction.
基金supported partially by National Natural Science Foundation of China(Nos.10905070,10875148 and 10728510)the Knowledge Innovation Program of the Chinese Academy of Sciences,the National Magnetic Confinement Fusion Science Program of China(No.2009GB106005)
文摘Fuel retention and recycling in plasma facing materials is a crucial issue for fusion devices, especially for the long pulse discharge devices. In this work, the deuterium retention and the surface erosion of SiC-coated graphite tiles exposed to EAST plasmas have been studied by post-mortem analyses, i.e., thermal desorption spectroscopy (TDS), secondary ion mass spec- troscopy (SIMS) and scanning electron microscopy (SEM). The results show that the sample cut from the high field side (HF) tile has been intensely eroded due to deuterium bombardment on plasma facing surfaces in the initial phase of discharges and trapped highest amount of deuterium. Lower deuterium retention has been found in the inner divertor sample, which is presumably due to the particular exposure history in the 2010 spring campaign.
基金Supported by the National Natural Science Foundation of China
文摘The present paper deals with the induced orientational order of the probe molecules dissolved in the uniaxially strained rubbers measured by using deuterium NMR. The distinctive dependence of the quadrupolar splitting on the swelling, elongation and crosslinking density was observed. The orientational order arising from the correlation between chain segments decreases with the increase of the numbers of both links between junctions and solvent molecules around segments.
文摘There is still very little information on the sources of water absorbed by oil palm plant. This information is very important for water management system in oil palm plantation. Thus, this study was carried out to determine current water sources absorbed by the oil palm roots using oxygen (δ18O) and deuterium isotopes (δD) techniques. Sketches of oxygen and deuterium isotope were total rainfall, throughfall, runoff, measurement at 5 soil depths (namely: 20 cm, 50 cm, 100 cm, 150 cm, and 200 cm), and oil palm stem. Results of this study showed huge variance in the values of oxygen and deuterium isotope. Based on Least Significant Difference (LSD) test, there was no significant value in the oxygen and deuterium isotope of stem water and others;however, a similar value was obtained at the depths of 0 - 20 cm and 20 - 50 cm with the stem water. This indicated that oil palm absorbed water from 0 - 50 cm depth. This result agreed with the oil palm rooting system, which has verified that the root quarter is the most active root of oil palm.
文摘Deuterium isotope effects in the CO2-reforming of methane to syngas were firstinvestigated over SiO2-supported rhodium catalysts. Normal deuterium isotop effect was morenoticeable on the methane conversion reaction than on the CO formation reaction, while there wasno such effect on the CO2 conversion reaction. It can be concluded that the dissociation of the C-Hbond in methane is a key mp and some CO is formed by the reverse water-gas shift reaction.
文摘After 290 h electrochemical charging of deuterium,the density of dislocation in well-annealed Pd was increased from 10~8/cm^2 to over 10~12/cm^2 and a large amount of bubble-like voids or cracks was observed by optical and transmission electron microscopes.The mechanism of deuterium cracking is believed due to the formation of molecular De during the segregstion and combination of deuterium atoms around dislocations.XRD results showed that the lattice constant of Pd increased from 0.3890 nm to 0.4034 nm.
文摘This article explores a technique for measuring the energy (NEL) value of feeds without respiration calorimetry or slaughter. The objectives were to compare results obtained from goats with those from cows, and to describe factors which limited the precision of these NEL estimates. One lactating Alpine doe and one lactateing Holstein cow were assigned to each of six different sequences of three 56-d feeding treatments consisting of low, medium, and high doses of the basal diet, rice bran, or hominy feed. This resulted in 30 observations of the basal diet and 12 of each byproduct feed for each species and utilized a total of 18 cows and 18 does. The NEL values of the basal diet, rice bran, and hominy feed were calculated as the sum of milk energy, change in body energy, and estimated fasting heat production per kilogram of feed dry matter. Milk energy was determined by bomb calorimetry and body energy from live body weight and deuterium oxide space. The NEL (MJ/kg) determined in this manner were basal diet, 5.73 and 5.98;rice bran, 7.11 and 7.07;and hominy feed, 6.99 and 8.20 for cows and goats, respectively.
文摘Stable neutron generation with a yield of ~1.2×10^(4) neutrons per pulse was obtained during d(d,n)^(3)He reaction initiated by the high-voltage nanosecond discharge in a gap with a potential tungsten cylinder(anode)and a grounded deuterated zirconium plate(cathode)filled with deuterium at a pressure of ~10^(2) Pa.Estimated duration of the neutron pulse was ~1.5 ns.Less intensive neutron emission was registered without deuterated plate.Splashing of material of the tungsten electrode was observed during the high-voltage nanosecond discharge in the deuterium,hydrogen,helium and argon at pressures of 10^(2)-10^(4) Pa.
文摘D+2 ions of 70 and 90 keV were separately implanted into two thick samples of sintered alumina ceramic and the distribution of deuterium has been measured for three runs at an interval of 5 months using high energy proton backscattering and elastic recoil detection (ERD). The measured data show that there is little diffusion of deuterium in A12O3 and the diffusion coefficient is deduced to be 1.1 ×10-17 cm2/s. The measured total concentration of implanted deuterium is 4.5×1018 at./cm2. The profile of hydrogen adsorbed on the surface of Al2O3 samples was also observed by ERD and 1H(19F, αγ)16O analysis. The distribution range of 1H in Al2O3 after deuterium implantation is much larger than that before one.
基金Project supported by the National Key Research and Development Program of China(Grant Nos.2017YFA0402300 and 2017YFA0403200)the National Natural Science Foundation of China(Grant No.11574034)+1 种基金the Innovation Development Foundation of China Academy of Engineering Physics(CAEP)(Grant No.CX20200029)the Science Challenge Project(Grant Nos.JCKY201612A501)。
文摘Based on our previous work(Phys.Plasmas 25 012704(2018)),a fitting formula is given for electron-ion energy partition fraction of 3.54-MeV fusion alpha particles in deuterium-tritium(DT) plasmas as a function of plasma mass density ρ,electron temperature T_(e),and ion temperature T_(i).The formula can be used in a huge range of the plasma state,where ρ varies between 1.0 g/cc~10.0^(3) g/cc and both T_(e) and T_(i) change from 0.1 keV to 100.0 keV.Relativistic effect for electrons is investigated including the effect of the projectile recoil in the plasmas at T_(e)≥ 50.0 keV.The partition fraction for T_(e)>T_(i) is found to be close to that for T_(e)=T_(i). The comparisons with other fitting results are made at some plasma densities when T_(e)=T_(i),and the difference is explained.The fitting result is very close to the calculated one in most cases,which is convenient for the simulation of alpha heating in hot dense DT plasmas for inertial confined fusion.
基金supported by the National MCF Energy R&D Program of China(No.2018YFE0313300)National Natural Science Foundation of China(Nos.52273224,51402116)the Fundamental Research Funds for the Central Universities(Nos.2018KFYYXJJ028,2019KFYXMBZ045)
文摘In this study,a Cr_(2)O_(3) nanosheet(Cr_(2)O_(3) NS)inserted Cr-Zr-O coating was developed as a hydrogen isotope permeation barrier.The Cr_(2)O_(3) NSs,fabricated by rapid heat treatment,were amorphous with a thickness of only several nanometers.These Cr_(2)O_(3) NSs were then incorporated into a Cr-Zr-O multi-metal oxide composite coating via a dip-coating method to form a coating.The effect of the Cr_(2)O_(3) NS concentration on the morphology,microstructure and deuterium permeation resistance of the coating was studied.With the addition of 1.0 g 1^(-1)Cr_(2)O_(3) NSs,compared with the Cr-Zr-O coating without NSs,the permeation reduction factor of the resultant coating was enhanced from 249℃to 575℃ at 500℃.The coating,with a thickness of nearly 193 nm,achieved a comparable deuterium resistance that was above two orders of magnitude higher than the steel substrate.The results show that ceramic NSs can serve as effective fillers for enhancing the coating performance when functioning as a hydrogen isotope barrier.
文摘Mass spectral behavior of some deuterated and non-deuterated substituted benzylglyoxals was characteristic in enolic structure which was also proved by NMR spectrum. Fragmentation of the title compounds in their mass spectra was ressonably explained in this paper.