Skeletal editing has emerged as a powerful tool in organic chemistry,enabling the simplification of synthetic routes to complex molecules[1].Indoles,electron-rich nitrogen-containing building blocks,represent privileg...Skeletal editing has emerged as a powerful tool in organic chemistry,enabling the simplification of synthetic routes to complex molecules[1].Indoles,electron-rich nitrogen-containing building blocks,represent privileged scaffolds prevalent in pharmaceuticals,natural products,and bioactive compounds.The application of skeletal editing strategies to modify such structures is highly valuable and in growing demand.Leveraging the electronrich nature of indoles at C2 and C3,single-carbon atom insertion using cationic carbyne equivalents offers an efficient approach for indole ring expansion to quinoline(Scheme 1a).However,existing methods predominantly rely on halocarbene precursors,which restricts the functional groups of ring-expanded products to halogen[2],alkyl,aryl,heteroaryl and ester moieties[3].This limitation hinders their utility in late-stage skeletal modifications of complex targets.展开更多
There is presented the review of publications connecting with creation of matrices for the immobilization of long-lived radionuclides and radioactive waste for storage and disposal, as well as for the transmutation. T...There is presented the review of publications connecting with creation of matrices for the immobilization of long-lived radionuclides and radioactive waste for storage and disposal, as well as for the transmutation. This paper substantiates the practicability and feasibility of obtaining the carbon matrces by carbonization of imidoderivatives.展开更多
Based on the temporal-spatial distribution features of ancient settlement sites from the middle and late Neolithic Age to the Han dynasty in the Chaohu Lake Basin of Anhui Province, East China, using the methods of GI...Based on the temporal-spatial distribution features of ancient settlement sites from the middle and late Neolithic Age to the Han dynasty in the Chaohu Lake Basin of Anhui Province, East China, using the methods of GIS combined with the reconstructed paleoen- vironment by the records of lake sediment since Holocene, the transmutation of ancient set- tlements with response to environmental changes in this area has been discussed. Studies show that the main feature of transmutation of ancient settlements from the middle and late Neolithic Age to the Han Dynasty was that the distribution of settlements in this area changed from high altitudes to low ones and kept approaching the Chaohu Lake with the passage of time. These could be the response to the climate change from warm-moist to a relatively warm-dry condition during the middle Holocene, leading to the lake level fluctuations. The large area of exposed land provided enough space for human activities. These indicate that the above changes in geomorphologic evolution and hydrology influenced by climate condi- tions affected the transmutation of ancient settlements greatly. The distribution pattern of settlement sites was that the number of sites in the west was more than in the east. This pattern may be related to the geomorphologic conditions such as frequent channel shifting of the Yangtze River as well as flood disasters during the Holocene optimum. Therefore, climate change was the inducement of the transmutation of ancient settlements in the Chaohu Lake Basin, which exerted great influence on the distribution, expansion and development of the ancient settlements.展开更多
Yeats'poems are famous for the use of symbolism.His symbolism is characterized by continuous development,which can be roughly divided into three phases:the early phase-from 1889 to 1904,the middle phase-from 1919 ...Yeats'poems are famous for the use of symbolism.His symbolism is characterized by continuous development,which can be roughly divided into three phases:the early phase-from 1889 to 1904,the middle phase-from 1919 to 1925,and the late phase-the years after 1925.We can see poems with different characters of symbolism in his different phases.In this paper,three poems are to be chosen to show his transmutation of symbolism.展开更多
The accelerator-driven subcritical system (ADS) with a hard neutron energy spectrum was used to study transmutation of minor actinides (MAs). The aim of the study was to improve the efficiency of MA transmutation whil...The accelerator-driven subcritical system (ADS) with a hard neutron energy spectrum was used to study transmutation of minor actinides (MAs). The aim of the study was to improve the efficiency of MA transmutation while ensuring that variations in the effective multiplication factor (keff) remained within safe margins during reactor operation. All calculations were completed using code COUPLE3.0. The subcritical reactor was operated at a thermal power level of 800 MW, and a mixture of mononitrides of MAs and plutonium (Pu) was used as fuel. Zirconium nitride (ZrN) was used as an inert matrix in the fuel elements. The initial mass composition in terms of weight percentages in the heavy metal component (IHM) was 30.6% Pu/IHM and 69.4% MA/IHM. To verify the feasibility of this MA loading scheme, variations in keff, the amplification factor of the core, maximum power density and the content of MAs and Pu were calculated over six refueling cycles. Each cycle was of 600 days duration, and therefore, there were 3600 effective full power days. Results demonstrated that the effective transmutation support ratio of MAs was approximately 28, and the ADS was able to efficiently transmute MAs. The changes in other physical parameters were also within their normal ranges.It is concluded that the proposed MA transmutation scheme for an ADS core is reasonable.展开更多
The transmutation of long-lived fission products through spallation induced by light nuclides was investi-gated for the purpose of determining the feasibility of this approach for long-lived fission products,in both e...The transmutation of long-lived fission products through spallation induced by light nuclides was investi-gated for the purpose of determining the feasibility of this approach for long-lived fission products,in both economic and environmental terms.The cross-section data were obtained from the TALYS Evaluated Nuclear Data Library(TENDL).A thick target model was used to study the consumption of the target isotopes in the transmutation process.The transmutation yield was calculated using the highest beam intensity available with the China initiative accelerator-driven system.It was found that the light nuclide-induced spallation reaction can significantly reduce the radio toxicity of the investigated long-lived fission products.Using the transmutation target made of elemental LLFP and the proton beam with an intensity of 5 mA,the consumption of 90 Sr,93 Zr,107 Pd,or 137 Cs can reach approximately 500 g per year.展开更多
The Fusion-Driven Sub-critical System (FDS) is one of the Chinese programs to be further developed for fusion application. Its Dual-cooled Waste Transmutation Blanket (DWTB), as one the most important part of the FDS ...The Fusion-Driven Sub-critical System (FDS) is one of the Chinese programs to be further developed for fusion application. Its Dual-cooled Waste Transmutation Blanket (DWTB), as one the most important part of the FDS is cooled by helium and liquid metal, and have the features of safety, tritium self-sustaining, high efficiency and feasibility. Its conceptual design has been finished. This paper is mainly involved with the basic structure design and thermal-hydraulics analysis of DWTB. On the basis of a three-dimensional (3-D) model of radial-toroidal sections of the segment box, thermal temperature gradients and structure analysis made with a comprehensive finite element method (FEM) have been performed with the computer code ANSYS5.7 and computational fluid dynamic finite element codes. The analysis refers to the steady-state operating condition of an outboard blanket segment. Furthermore, the mechanical loads due to coolant pressure in normal operating conditions have been also taken into account. All the above loads have been combined as an input for a FEM stress analysis and the resulting stress distribution has been evaluated. Finally, the structure design and Pb-17Li flow velocity has been optimized according to the calculations and analysis.展开更多
Herein, we assess the129I transmutation capability of a 2250-MWt single-fluid double-zone thorium molten salt reactor(SD-TMSR) by considering two methods. One is realized by loading an appropriate amount of129I before...Herein, we assess the129I transmutation capability of a 2250-MWt single-fluid double-zone thorium molten salt reactor(SD-TMSR) by considering two methods. One is realized by loading an appropriate amount of129I before the startup of the reactor, and the amount of129I during operation is kept constant by online feeding129I.The other adopts only an initial loading of129I before startup, and no other129I is fed online during operation.The investigation first focuses on the effect of the loading of I on the Th-233U isobreeding performance. The results indicate that a233U isobreeding mode can be achieved for both scenarios for a 60-year operation when the initial molar proportion of LiI is maintained within 0.40% and 0.87%, respectively. Then, the transmutation performances for the two scenarios are compared by changing the amount of injected iodine into the core. It is found that the scenario that adopts an initial loading of129I shows a slightly better transmutation performance in comparison with the scenario that adopts online feeding of129I when the net233U productions for the two scenarios are kept equal. The initial loading of129I scenario with LiI = 0.87% molar proportion is recommended for129I transmutation in the SD-TMSR,and can transmute 1.88 t of129I in the233U isobreeding mode over 60 years.展开更多
Spherical Nano-scale nickel hydroxide was prepared through precipitation transmutation method by controlling the transmutation conditions in this paper. The measurement results of XRD and TEM indicate that the crystal...Spherical Nano-scale nickel hydroxide was prepared through precipitation transmutation method by controlling the transmutation conditions in this paper. The measurement results of XRD and TEM indicate that the crystallization of the nano-scale nickel hydroxide isβ-style and its shape is spherical with a diameter of 40～70 nanometer. The adulteration experiment shows that the adulteration ratio of nano- scale Ni(OH) 2 in common spherical micrometer-scale Ni(OH) 2 exists a optimal value (1∶9). And at this point, the utilization ratio of Ni(OH) 2 in electrodes can be raised by 10%, and the nano-scale nickel hydroxide with sphericity shape shows a better adulteration performance than that with needle shape.展开更多
Some experiments on radiation of hydrocarbons and the alloys including Bismuth and Lead by power nanosecond electromagnetic pulses are described. The list of the used equipment and technique of experiments are given. ...Some experiments on radiation of hydrocarbons and the alloys including Bismuth and Lead by power nanosecond electromagnetic pulses are described. The list of the used equipment and technique of experiments are given. The result of these experiences is change of a chemical composition of the irradiated samples in comparison with the initial ones. Conversion of part of Bismuth to Lead is observed. The hypothesis of such changes is made.展开更多
A tokamak fusion-fission hybrid reactor is proposed as one of candidates for disposal of the long-lived actinides and fission product wastes and supply of future energy. To assess the feasibility of transmutation of l...A tokamak fusion-fission hybrid reactor is proposed as one of candidates for disposal of the long-lived actinides and fission product wastes and supply of future energy. To assess the feasibility of transmutation of long-lived radiowastes using fusion-fission hybrid reactors, a fusion core design is presented and several possible conceptual blankets are studied, for, respectively, actinides transmutation and fission product transmutation. The results show that actinides and fission products may be effectively transmuted using the presented hybrid reactors.展开更多
The research and development history of silicon Neutron Transmutation Doping (NTD) technology and its applications at home and abroad are introduced in this paper.The advantages of NTD,compared with conventional techn...The research and development history of silicon Neutron Transmutation Doping (NTD) technology and its applications at home and abroad are introduced in this paper.The advantages of NTD,compared with conventional technology of doping,are narrated.The principle of NTD as well as the implementation of the main procedures related to Si NTD is explained.The market demand tendency is prospected,and the advanced measures on NTD quality control are described.展开更多
This paper designed an admeasuring apparatus of cage guide’ transmutation based on C8051F340.Cage guide is very important to mine’ hoisting system,but it hasn’t a good idea to measure its transmutation.The instrume...This paper designed an admeasuring apparatus of cage guide’ transmutation based on C8051F340.Cage guide is very important to mine’ hoisting system,but it hasn’t a good idea to measure its transmutation.The instrument measure cage guide’s crosswise distance and longitudinal distance through displacement transducer and shaft encoder,and use C8051F340’ USB controller communicate with upper monitor.The upper monitor will display cage guide’s configuration.Its feasibility has been proved by field tests.展开更多
A burnup calculation was performed to analyze the Apr`es ORIENT process, which aims to create highlyvaluable elements from fission products separated from spent nuclear fuels. The basic idea is to use nuclear transmut...A burnup calculation was performed to analyze the Apr`es ORIENT process, which aims to create highlyvaluable elements from fission products separated from spent nuclear fuels. The basic idea is to use nuclear transmutation induced by a neutron capture reaction followed by a β-decay, thus changing the atomic number Z of a target element in fission products by 1 unit. LWR(PWR) and FBR(MONJU) were considered as the transmutation devices. High rates of creation were obtained in some cases of platinum group metals(44Ru by FBR,46 Pd by LWR) and rare earth(64Gd by LWR,66 Dy by FBR). Therefore, systems based on LWR and FBR have their own advantages depending on target elements. Furthermore, it was found that creation rates of even Z(= Z + 1) elements from odd Z ones were higher than the opposite cases. This creation rate of an element was interpreted in terms of "average 1-group neutron capture cross section of the corresponding target element σc Z defined in this work. General trends of the creation rate of an even(odd) Z element from the corresponding odd(even) Z one were found to be proportional to the 0.78th(0.63th) power of σc Z, however with noticeable dispersion. The difference in the powers in the above analysis was explained by the difference in the number of stable isotopes caused by the even-odd effect of Z.展开更多
This paper analyzes the big trip phenomenon, restricting it to happen only in the context of the multiverse when the involved wormhole is asymptotically flat and recent criticisms are pointless. A new kind of Lorentzi...This paper analyzes the big trip phenomenon, restricting it to happen only in the context of the multiverse when the involved wormhole is asymptotically flat and recent criticisms are pointless. A new kind of Lorentzian asymptotically anti-de Sitter wormholes is considered in some detail and it is seen that such wormholes cannot contribute the big trip phenomenon. The ideas of big trip, multiverse and Boltzmann brains are then used to advance the conjecture of cosmic transmutation according to which the host universe where one of the mouths of a grown up wormhole is inserted may be converted into a universe similar to the traveling one if the latter contains a civilization which is typical also in the host universe. The origin of life in the context of the multiverse is then briefly discussed.展开更多
Under the background of rapid progress of science and technology,the trend of media integration is constantly strengthened,which urges the original media management concept to be constantly changed and to form a new m...Under the background of rapid progress of science and technology,the trend of media integration is constantly strengthened,which urges the original media management concept to be constantly changed and to form a new media management concept.In order to apply to the development needs under the trend of media integration.This paper summarizes the media integration,analyzes the influence of the media integration trend on the media management concept,explores the direction of the evolution of the media management concept under the media integration trend,and aims to provide a reference for the development of the media industry.展开更多
The objective of this paper is to discuss the option of recycling and transmutation of radioactive waste against once-through fuel cycle based on uranium feed under the perspective of sustainability. A qualitative ana...The objective of this paper is to discuss the option of recycling and transmutation of radioactive waste against once-through fuel cycle based on uranium feed under the perspective of sustainability. A qualitative analysis was carried out to compare the fuel cycles considering different options for burning and recycling transuranic and fission products utilizing accelerator driven systems, fast reactors, and light water reactors. The results show that recycling and transmutation fuel cycles are more attractive than the current once-through fuel cycles from the point of view of sustainability. The main conclusion is that the decision about the construction of deep geological repositories for spent fuel disposal must be reevaluated.展开更多
Low energy nuclear reactions are possible in condensed matter because of image forces. They result from induced charges at the surface of metals or very polarizable media. The height and width of the Coulomb barrier i...Low energy nuclear reactions are possible in condensed matter because of image forces. They result from induced charges at the surface of metals or very polarizable media. The height and width of the Coulomb barrier in free space can thus be reduced. Nuclear fusion requires also the formation of a compound nucleus in one of its excited states, but two deuterons yield an α particle that has 2 excited states. They are respectively accessible at high or low energies. Since the reduction of the Coulomb barrier depends on the local curvature of the interface, cold fusion becomes autocatalytic, but heat production is controllable. Even microbes, plants and animals can produce transmutations. They are also due to image forces. This solves a basic problem in nuclear physics and there are possible applications: facilitated synthesis of superheavy elements and development of a new type of energy sources. They are moderate, but safe.展开更多
Coin flipping by telephone protocol（CFP） is utilized in a system to exchange a binary sequence at random between two person apart far from each other. However, CFP cannot he used in a system with many users like in ...Coin flipping by telephone protocol（CFP） is utilized in a system to exchange a binary sequence at random between two person apart far from each other. However, CFP cannot he used in a system with many users like in a group environment system. A transmutation of CFP named T-CFP is proposed in this paper. The precondition of T-CFP is the system＇s user trusts the system center and center＇s cheating is meaningless at the same time. The significant difference between CFP and T-CFP is that CFP supports only two users while T-CFP can support many users to exchange special information. The security and efficiency of T-CFP are discussed with a detailed example on T-CFP utilization is demonstrated in this paper.展开更多
文摘Skeletal editing has emerged as a powerful tool in organic chemistry,enabling the simplification of synthetic routes to complex molecules[1].Indoles,electron-rich nitrogen-containing building blocks,represent privileged scaffolds prevalent in pharmaceuticals,natural products,and bioactive compounds.The application of skeletal editing strategies to modify such structures is highly valuable and in growing demand.Leveraging the electronrich nature of indoles at C2 and C3,single-carbon atom insertion using cationic carbyne equivalents offers an efficient approach for indole ring expansion to quinoline(Scheme 1a).However,existing methods predominantly rely on halocarbene precursors,which restricts the functional groups of ring-expanded products to halogen[2],alkyl,aryl,heteroaryl and ester moieties[3].This limitation hinders their utility in late-stage skeletal modifications of complex targets.
文摘There is presented the review of publications connecting with creation of matrices for the immobilization of long-lived radionuclides and radioactive waste for storage and disposal, as well as for the transmutation. This paper substantiates the practicability and feasibility of obtaining the carbon matrces by carbonization of imidoderivatives.
基金Major Program of Natural Science Research at University of Anhui Province, No.ZD200908 National Sci ence and Technology Support Program, No.2010BAK67B02+1 种基金 National Natural Science Foundation of China, No.41010104005 No.40971115This work is supported by the Tracing Origin Project of Chinese Civilization. We thank Dr. An Ran and Dr. Heim. Jordan in Purdue University, USA, for their kind help and valuable discussions.
文摘Based on the temporal-spatial distribution features of ancient settlement sites from the middle and late Neolithic Age to the Han dynasty in the Chaohu Lake Basin of Anhui Province, East China, using the methods of GIS combined with the reconstructed paleoen- vironment by the records of lake sediment since Holocene, the transmutation of ancient set- tlements with response to environmental changes in this area has been discussed. Studies show that the main feature of transmutation of ancient settlements from the middle and late Neolithic Age to the Han Dynasty was that the distribution of settlements in this area changed from high altitudes to low ones and kept approaching the Chaohu Lake with the passage of time. These could be the response to the climate change from warm-moist to a relatively warm-dry condition during the middle Holocene, leading to the lake level fluctuations. The large area of exposed land provided enough space for human activities. These indicate that the above changes in geomorphologic evolution and hydrology influenced by climate condi- tions affected the transmutation of ancient settlements greatly. The distribution pattern of settlement sites was that the number of sites in the west was more than in the east. This pattern may be related to the geomorphologic conditions such as frequent channel shifting of the Yangtze River as well as flood disasters during the Holocene optimum. Therefore, climate change was the inducement of the transmutation of ancient settlements in the Chaohu Lake Basin, which exerted great influence on the distribution, expansion and development of the ancient settlements.
文摘Yeats'poems are famous for the use of symbolism.His symbolism is characterized by continuous development,which can be roughly divided into three phases:the early phase-from 1889 to 1904,the middle phase-from 1919 to 1925,and the late phase-the years after 1925.We can see poems with different characters of symbolism in his different phases.In this paper,three poems are to be chosen to show his transmutation of symbolism.
基金supported by the Strategic Priority Research Program of The Chinese Academy of Sciences(No.XDA21010202)
文摘The accelerator-driven subcritical system (ADS) with a hard neutron energy spectrum was used to study transmutation of minor actinides (MAs). The aim of the study was to improve the efficiency of MA transmutation while ensuring that variations in the effective multiplication factor (keff) remained within safe margins during reactor operation. All calculations were completed using code COUPLE3.0. The subcritical reactor was operated at a thermal power level of 800 MW, and a mixture of mononitrides of MAs and plutonium (Pu) was used as fuel. Zirconium nitride (ZrN) was used as an inert matrix in the fuel elements. The initial mass composition in terms of weight percentages in the heavy metal component (IHM) was 30.6% Pu/IHM and 69.4% MA/IHM. To verify the feasibility of this MA loading scheme, variations in keff, the amplification factor of the core, maximum power density and the content of MAs and Pu were calculated over six refueling cycles. Each cycle was of 600 days duration, and therefore, there were 3600 effective full power days. Results demonstrated that the effective transmutation support ratio of MAs was approximately 28, and the ADS was able to efficiently transmute MAs. The changes in other physical parameters were also within their normal ranges.It is concluded that the proposed MA transmutation scheme for an ADS core is reasonable.
基金supported by the National Natural Science Foundation of China(No.11875328).
文摘The transmutation of long-lived fission products through spallation induced by light nuclides was investi-gated for the purpose of determining the feasibility of this approach for long-lived fission products,in both economic and environmental terms.The cross-section data were obtained from the TALYS Evaluated Nuclear Data Library(TENDL).A thick target model was used to study the consumption of the target isotopes in the transmutation process.The transmutation yield was calculated using the highest beam intensity available with the China initiative accelerator-driven system.It was found that the light nuclide-induced spallation reaction can significantly reduce the radio toxicity of the investigated long-lived fission products.Using the transmutation target made of elemental LLFP and the proton beam with an intensity of 5 mA,the consumption of 90 Sr,93 Zr,107 Pd,or 137 Cs can reach approximately 500 g per year.
基金Naional Nature Scienc Foundaion of China(No.10175067 and No.10175068)
文摘The Fusion-Driven Sub-critical System (FDS) is one of the Chinese programs to be further developed for fusion application. Its Dual-cooled Waste Transmutation Blanket (DWTB), as one the most important part of the FDS is cooled by helium and liquid metal, and have the features of safety, tritium self-sustaining, high efficiency and feasibility. Its conceptual design has been finished. This paper is mainly involved with the basic structure design and thermal-hydraulics analysis of DWTB. On the basis of a three-dimensional (3-D) model of radial-toroidal sections of the segment box, thermal temperature gradients and structure analysis made with a comprehensive finite element method (FEM) have been performed with the computer code ANSYS5.7 and computational fluid dynamic finite element codes. The analysis refers to the steady-state operating condition of an outboard blanket segment. Furthermore, the mechanical loads due to coolant pressure in normal operating conditions have been also taken into account. All the above loads have been combined as an input for a FEM stress analysis and the resulting stress distribution has been evaluated. Finally, the structure design and Pb-17Li flow velocity has been optimized according to the calculations and analysis.
基金supported by the Chinese TMSR Strategic Pioneer Science and Technology Project(No.XDA02010000)the Frontier Science Key Program of the Chinese Academy of Sciences(No.QYZDY-SSW-JSC016)
文摘Herein, we assess the129I transmutation capability of a 2250-MWt single-fluid double-zone thorium molten salt reactor(SD-TMSR) by considering two methods. One is realized by loading an appropriate amount of129I before the startup of the reactor, and the amount of129I during operation is kept constant by online feeding129I.The other adopts only an initial loading of129I before startup, and no other129I is fed online during operation.The investigation first focuses on the effect of the loading of I on the Th-233U isobreeding performance. The results indicate that a233U isobreeding mode can be achieved for both scenarios for a 60-year operation when the initial molar proportion of LiI is maintained within 0.40% and 0.87%, respectively. Then, the transmutation performances for the two scenarios are compared by changing the amount of injected iodine into the core. It is found that the scenario that adopts an initial loading of129I shows a slightly better transmutation performance in comparison with the scenario that adopts online feeding of129I when the net233U productions for the two scenarios are kept equal. The initial loading of129I scenario with LiI = 0.87% molar proportion is recommended for129I transmutation in the SD-TMSR,and can transmute 1.88 t of129I in the233U isobreeding mode over 60 years.
文摘Spherical Nano-scale nickel hydroxide was prepared through precipitation transmutation method by controlling the transmutation conditions in this paper. The measurement results of XRD and TEM indicate that the crystallization of the nano-scale nickel hydroxide isβ-style and its shape is spherical with a diameter of 40～70 nanometer. The adulteration experiment shows that the adulteration ratio of nano- scale Ni(OH) 2 in common spherical micrometer-scale Ni(OH) 2 exists a optimal value (1∶9). And at this point, the utilization ratio of Ni(OH) 2 in electrodes can be raised by 10%, and the nano-scale nickel hydroxide with sphericity shape shows a better adulteration performance than that with needle shape.
文摘Some experiments on radiation of hydrocarbons and the alloys including Bismuth and Lead by power nanosecond electromagnetic pulses are described. The list of the used equipment and technique of experiments are given. The result of these experiences is change of a chemical composition of the irradiated samples in comparison with the initial ones. Conversion of part of Bismuth to Lead is observed. The hypothesis of such changes is made.
基金the High Technology Research and Development Programme of china.
文摘A tokamak fusion-fission hybrid reactor is proposed as one of candidates for disposal of the long-lived actinides and fission product wastes and supply of future energy. To assess the feasibility of transmutation of long-lived radiowastes using fusion-fission hybrid reactors, a fusion core design is presented and several possible conceptual blankets are studied, for, respectively, actinides transmutation and fission product transmutation. The results show that actinides and fission products may be effectively transmuted using the presented hybrid reactors.
文摘The research and development history of silicon Neutron Transmutation Doping (NTD) technology and its applications at home and abroad are introduced in this paper.The advantages of NTD,compared with conventional technology of doping,are narrated.The principle of NTD as well as the implementation of the main procedures related to Si NTD is explained.The market demand tendency is prospected,and the advanced measures on NTD quality control are described.
文摘This paper designed an admeasuring apparatus of cage guide’ transmutation based on C8051F340.Cage guide is very important to mine’ hoisting system,but it hasn’t a good idea to measure its transmutation.The instrument measure cage guide’s crosswise distance and longitudinal distance through displacement transducer and shaft encoder,and use C8051F340’ USB controller communicate with upper monitor.The upper monitor will display cage guide’s configuration.Its feasibility has been proved by field tests.
文摘A burnup calculation was performed to analyze the Apr`es ORIENT process, which aims to create highlyvaluable elements from fission products separated from spent nuclear fuels. The basic idea is to use nuclear transmutation induced by a neutron capture reaction followed by a β-decay, thus changing the atomic number Z of a target element in fission products by 1 unit. LWR(PWR) and FBR(MONJU) were considered as the transmutation devices. High rates of creation were obtained in some cases of platinum group metals(44Ru by FBR,46 Pd by LWR) and rare earth(64Gd by LWR,66 Dy by FBR). Therefore, systems based on LWR and FBR have their own advantages depending on target elements. Furthermore, it was found that creation rates of even Z(= Z + 1) elements from odd Z ones were higher than the opposite cases. This creation rate of an element was interpreted in terms of "average 1-group neutron capture cross section of the corresponding target element σc Z defined in this work. General trends of the creation rate of an even(odd) Z element from the corresponding odd(even) Z one were found to be proportional to the 0.78th(0.63th) power of σc Z, however with noticeable dispersion. The difference in the powers in the above analysis was explained by the difference in the number of stable isotopes caused by the even-odd effect of Z.
文摘This paper analyzes the big trip phenomenon, restricting it to happen only in the context of the multiverse when the involved wormhole is asymptotically flat and recent criticisms are pointless. A new kind of Lorentzian asymptotically anti-de Sitter wormholes is considered in some detail and it is seen that such wormholes cannot contribute the big trip phenomenon. The ideas of big trip, multiverse and Boltzmann brains are then used to advance the conjecture of cosmic transmutation according to which the host universe where one of the mouths of a grown up wormhole is inserted may be converted into a universe similar to the traveling one if the latter contains a civilization which is typical also in the host universe. The origin of life in the context of the multiverse is then briefly discussed.
文摘Under the background of rapid progress of science and technology,the trend of media integration is constantly strengthened,which urges the original media management concept to be constantly changed and to form a new media management concept.In order to apply to the development needs under the trend of media integration.This paper summarizes the media integration,analyzes the influence of the media integration trend on the media management concept,explores the direction of the evolution of the media management concept under the media integration trend,and aims to provide a reference for the development of the media industry.
文摘The objective of this paper is to discuss the option of recycling and transmutation of radioactive waste against once-through fuel cycle based on uranium feed under the perspective of sustainability. A qualitative analysis was carried out to compare the fuel cycles considering different options for burning and recycling transuranic and fission products utilizing accelerator driven systems, fast reactors, and light water reactors. The results show that recycling and transmutation fuel cycles are more attractive than the current once-through fuel cycles from the point of view of sustainability. The main conclusion is that the decision about the construction of deep geological repositories for spent fuel disposal must be reevaluated.
文摘Low energy nuclear reactions are possible in condensed matter because of image forces. They result from induced charges at the surface of metals or very polarizable media. The height and width of the Coulomb barrier in free space can thus be reduced. Nuclear fusion requires also the formation of a compound nucleus in one of its excited states, but two deuterons yield an α particle that has 2 excited states. They are respectively accessible at high or low energies. Since the reduction of the Coulomb barrier depends on the local curvature of the interface, cold fusion becomes autocatalytic, but heat production is controllable. Even microbes, plants and animals can produce transmutations. They are also due to image forces. This solves a basic problem in nuclear physics and there are possible applications: facilitated synthesis of superheavy elements and development of a new type of energy sources. They are moderate, but safe.
基金Supported by the National Natural Science Foun-dation of China(60473072)
文摘Coin flipping by telephone protocol（CFP） is utilized in a system to exchange a binary sequence at random between two person apart far from each other. However, CFP cannot he used in a system with many users like in a group environment system. A transmutation of CFP named T-CFP is proposed in this paper. The precondition of T-CFP is the system＇s user trusts the system center and center＇s cheating is meaningless at the same time. The significant difference between CFP and T-CFP is that CFP supports only two users while T-CFP can support many users to exchange special information. The security and efficiency of T-CFP are discussed with a detailed example on T-CFP utilization is demonstrated in this paper.
