Unconventional magnetism,including altermagnetism and unconventional compensated magnetism,characterized by its duality of real-space antiferromagnetic alignment and momentum-space spin splitting,has garnered widespre...Unconventional magnetism,including altermagnetism and unconventional compensated magnetism,characterized by its duality of real-space antiferromagnetic alignment and momentum-space spin splitting,has garnered widespread attention.While altermagnetism has been extensively studied,research on unconventional compensated magnetism remains very rare.In particular,unconventional compensated magnetic materials are only theoretically predicted and have not yet been synthesized experimentally.In this study,based on symmetry analysis and frst-principles electronic structure calculations,we predict that LaMn_(2)SbO_(6)is an unconventional compensated magnetic semiconductor.Given that the Mn ions at opposite spin lattice cannot be connected by any symmetry,the spin splitting in LaMn_(2)SbO_(6)is isotropic.More importantly,LaMn_(2)SbO_(6)has already been synthesized experimentally,and its magnetic structure has been confrmed by neutron scattering experiments.Therefore,LaMn_(2)SbO_(6)serves as an excellent material platform for investigating the novel physical properties of unconventional compensated magnetic materials.展开更多
CoQ is an essential electron cartier in the mitochondrial respiratory chain of both eukaryotes and prokaryotes. It consists of a benzoquinone head group and a hydrophobic polyisoprenoid tail. The genes （COQ1-9） invo...CoQ is an essential electron cartier in the mitochondrial respiratory chain of both eukaryotes and prokaryotes. It consists of a benzoquinone head group and a hydrophobic polyisoprenoid tail. The genes （COQ1-9） involved in CoQ biosynthesis have been characterized in yeast. In this study, we generated and molecularly characterized a mutant allele of a novel Drosophila gene, sbo, which encodes a protein that is predicted to catalyze the prenylation of p-hydroxybenzoate with the isoprenoid chain during the process of CoQ synthesis. Expression of sbo in yeast rescues the lethality of ACOQ2 mutant cells, indicating that sbo is a functional homolog of COQ2. HPLC results show that the levels of CoQ9 and COQlo were significantly reduced in sbo heterozygous adult flies. Furthermore, the mean lifespans of males and females heterozygous for sbo are extended by 12.5% and 30.8%, respectively. Homozygous sbo animals exhibit reduced activities of the insulin/insulin-like growth factor signaling （IIS） pathway. Taken together, we conclude that sbo is an essential gene for Drosophila development, mutation of which leads to an extension of lifespan most likely by altering endogenous CoQ biosynthesis.展开更多
To mitigate consequences of core melting,an ex-vessel core catcher is investigated in this study.Instructions should be obeyed to cool down the corium caused by core melting.The corium destroys the reactor containment...To mitigate consequences of core melting,an ex-vessel core catcher is investigated in this study.Instructions should be obeyed to cool down the corium caused by core melting.The corium destroys the reactor containment and causes radioactive materials to be released into the environment if it does not cool down well.It is important to build a core catcher system for the reception,localization,and cool down of the molten corium during a severe accident resulting from core melting.In this study,the role of a core catcher in the VVER-1000/v528 reactor containment during a station black out(SBO)accident is evaluated using the MELCOR1.8.6 code.In addition,parametric analyses of the SBO for(i)SBO accidents with emergency core cooling system(ECCS)operation,and(ii)without ECCS operation are performed.Furthermore,thermal–hydraulic analyses in dry and wet cavities with/without water are conducted.The investigations include the reduction of gases resulting from molten–corium–concrete interactions(H_(2),CO,CO_(2)).Core melting,gas production,and the pressure/temperature in the reactor containment are assessed.Additionally,a full investigation pertaining to gas release(H_(2),CO,CO_(2))and the pressure/temperature of the core catcher is performed.Based on MELCOR simulations,a core cavity and a perimeter water channel are the best options for corium cooling and a lower radionuclide release.This simulation is also theoretically investigated and discussed herein.The simulation results show that the core catcher system in addition to an internal sacrificial material reduces the containment pressure from 689 to 580 kPa and the corresponding temperature from 394 to 380 K.Furthermore,it is observed that the amount of gases produced,particularly hydrogen,decreased from 1698 to 1235 kg.Moreover,the presence of supporting systems,including an ECCS with a core catcher,prolonged the core melting time from 16,430 to 28,630 s(in an SBO accident)and significantly decreased the gases produced.展开更多
针对SBO(school based optimization)算法搜索性能差、易陷入局部最优等缺陷,提出融入教育心理学的SBO算法(SBO based on educational psychology,SBO-EP)。在教阶段,引入最近发展区理论,对学生进行分组动态教学,提高算法的探索能力;引...针对SBO(school based optimization)算法搜索性能差、易陷入局部最优等缺陷,提出融入教育心理学的SBO算法(SBO based on educational psychology,SBO-EP)。在教阶段,引入最近发展区理论,对学生进行分组动态教学,提高算法的探索能力;引用成就动机理论加入自学阶段,针对每组学生的成就动机设计动态自学方式,提高算法的开发能力;在每轮学习过程结束后参考同伴效应设置班级重组操作,增加解的多样性。采用40个CEC2021测试函数和20个其他类型测试函数进行数值实验,并将SBO-EP算法与蚁群优化算法、基于球形矢量的粒子群优化算法、阿基米德优化算法、灰狼优化算法、教与学优化算法、融合认知心理学的教与学优化算法、学生心理学优化算法进行对比分析。结果表明,SBO-EP算法在收敛速度、寻优精度及稳定性上优势明显。最后,对三种策略的组合进行对比实验,验证了改进策略的有效性。展开更多
本文是基于SBO的数据仓库的设计,针对SBO的业务需求设计了数据仓库的总体架构,并以销售主题为例介绍了SBO数据仓库数据模型的设计。最后在Windows XP平台上,选择在SBO内部利用SQL Server 2000构建数据仓库,并按照SBO的统一标准设置字段...本文是基于SBO的数据仓库的设计,针对SBO的业务需求设计了数据仓库的总体架构,并以销售主题为例介绍了SBO数据仓库数据模型的设计。最后在Windows XP平台上,选择在SBO内部利用SQL Server 2000构建数据仓库,并按照SBO的统一标准设置字段;中间服务器采用SQL Server 2000自带的Analysis Services来实现。展开更多
基金supported by the National Natural Science Foundation of China(Grant Nos.12204533,12434009,and 62476278)the National Key R&D Program of China(Grant No.2024YFA1408601)+1 种基金the Fundamental Research Funds for the Central Universitiesthe Research Funds of Renmin University of China(Grant No.24XNKJ15)。
文摘Unconventional magnetism,including altermagnetism and unconventional compensated magnetism,characterized by its duality of real-space antiferromagnetic alignment and momentum-space spin splitting,has garnered widespread attention.While altermagnetism has been extensively studied,research on unconventional compensated magnetism remains very rare.In particular,unconventional compensated magnetic materials are only theoretically predicted and have not yet been synthesized experimentally.In this study,based on symmetry analysis and frst-principles electronic structure calculations,we predict that LaMn_(2)SbO_(6)is an unconventional compensated magnetic semiconductor.Given that the Mn ions at opposite spin lattice cannot be connected by any symmetry,the spin splitting in LaMn_(2)SbO_(6)is isotropic.More importantly,LaMn_(2)SbO_(6)has already been synthesized experimentally,and its magnetic structure has been confrmed by neutron scattering experiments.Therefore,LaMn_(2)SbO_(6)serves as an excellent material platform for investigating the novel physical properties of unconventional compensated magnetic materials.
基金supported by the National Science Foundation of China(Nos.31071087 and 30771217) the National Basic Research Program(973 Program)(No. 2009CB918702)
文摘CoQ is an essential electron cartier in the mitochondrial respiratory chain of both eukaryotes and prokaryotes. It consists of a benzoquinone head group and a hydrophobic polyisoprenoid tail. The genes （COQ1-9） involved in CoQ biosynthesis have been characterized in yeast. In this study, we generated and molecularly characterized a mutant allele of a novel Drosophila gene, sbo, which encodes a protein that is predicted to catalyze the prenylation of p-hydroxybenzoate with the isoprenoid chain during the process of CoQ synthesis. Expression of sbo in yeast rescues the lethality of ACOQ2 mutant cells, indicating that sbo is a functional homolog of COQ2. HPLC results show that the levels of CoQ9 and COQlo were significantly reduced in sbo heterozygous adult flies. Furthermore, the mean lifespans of males and females heterozygous for sbo are extended by 12.5% and 30.8%, respectively. Homozygous sbo animals exhibit reduced activities of the insulin/insulin-like growth factor signaling （IIS） pathway. Taken together, we conclude that sbo is an essential gene for Drosophila development, mutation of which leads to an extension of lifespan most likely by altering endogenous CoQ biosynthesis.
文摘To mitigate consequences of core melting,an ex-vessel core catcher is investigated in this study.Instructions should be obeyed to cool down the corium caused by core melting.The corium destroys the reactor containment and causes radioactive materials to be released into the environment if it does not cool down well.It is important to build a core catcher system for the reception,localization,and cool down of the molten corium during a severe accident resulting from core melting.In this study,the role of a core catcher in the VVER-1000/v528 reactor containment during a station black out(SBO)accident is evaluated using the MELCOR1.8.6 code.In addition,parametric analyses of the SBO for(i)SBO accidents with emergency core cooling system(ECCS)operation,and(ii)without ECCS operation are performed.Furthermore,thermal–hydraulic analyses in dry and wet cavities with/without water are conducted.The investigations include the reduction of gases resulting from molten–corium–concrete interactions(H_(2),CO,CO_(2)).Core melting,gas production,and the pressure/temperature in the reactor containment are assessed.Additionally,a full investigation pertaining to gas release(H_(2),CO,CO_(2))and the pressure/temperature of the core catcher is performed.Based on MELCOR simulations,a core cavity and a perimeter water channel are the best options for corium cooling and a lower radionuclide release.This simulation is also theoretically investigated and discussed herein.The simulation results show that the core catcher system in addition to an internal sacrificial material reduces the containment pressure from 689 to 580 kPa and the corresponding temperature from 394 to 380 K.Furthermore,it is observed that the amount of gases produced,particularly hydrogen,decreased from 1698 to 1235 kg.Moreover,the presence of supporting systems,including an ECCS with a core catcher,prolonged the core melting time from 16,430 to 28,630 s(in an SBO accident)and significantly decreased the gases produced.
文摘针对SBO(school based optimization)算法搜索性能差、易陷入局部最优等缺陷,提出融入教育心理学的SBO算法(SBO based on educational psychology,SBO-EP)。在教阶段,引入最近发展区理论,对学生进行分组动态教学,提高算法的探索能力;引用成就动机理论加入自学阶段,针对每组学生的成就动机设计动态自学方式,提高算法的开发能力;在每轮学习过程结束后参考同伴效应设置班级重组操作,增加解的多样性。采用40个CEC2021测试函数和20个其他类型测试函数进行数值实验,并将SBO-EP算法与蚁群优化算法、基于球形矢量的粒子群优化算法、阿基米德优化算法、灰狼优化算法、教与学优化算法、融合认知心理学的教与学优化算法、学生心理学优化算法进行对比分析。结果表明,SBO-EP算法在收敛速度、寻优精度及稳定性上优势明显。最后,对三种策略的组合进行对比实验,验证了改进策略的有效性。
文摘本文是基于SBO的数据仓库的设计,针对SBO的业务需求设计了数据仓库的总体架构,并以销售主题为例介绍了SBO数据仓库数据模型的设计。最后在Windows XP平台上,选择在SBO内部利用SQL Server 2000构建数据仓库,并按照SBO的统一标准设置字段;中间服务器采用SQL Server 2000自带的Analysis Services来实现。
