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一些capable 3-群 被引量:3
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作者 李志秀 《安徽大学学报(自然科学版)》 CAS 北大核心 2020年第3期22-24,共3页
对于一个给定的群G,如果能有另外的一个群H,满足H/Z(H)■G,则称G是capable群,或称G可以充当中心商.对capable群的研究在p-群分类问题中起着相当重要的作用.借助群的扩张理论,通过换位子计算,得到了一些特殊的3-群为capable群,并且由群G... 对于一个给定的群G,如果能有另外的一个群H,满足H/Z(H)■G,则称G是capable群,或称G可以充当中心商.对capable群的研究在p-群分类问题中起着相当重要的作用.借助群的扩张理论,通过换位子计算,得到了一些特殊的3-群为capable群,并且由群G构造出了群H,使得H/Z(H)■G. 展开更多
关键词 capable 3-群 循环扩张 自同构
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一些特殊的capable群 被引量:5
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作者 李志秀 《晋中学院学报》 2010年第3期27-28,共2页
若存在一个群H,使得H/Z(H)同构于群G,则称群G为capable群.对capable群的研究在p-群的分类问题中起着至关重要的作用.运用群的循环扩张理论,通过换位子计算可以得到与Baer关于交换的capable群G完全一致的结果.
关键词 capable 交换群 德特肯群
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内亚循环capable群性质研究 被引量:1
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作者 李志秀 《山东科学》 CAS 2015年第5期77-79,共3页
本文研究了内亚循环p-群G满足capable群的条件,得到了这类群为capable p-群的充要条件。并由内亚循环p-群G构造得出了群H,满足H/Z(H)同构于G。
关键词 capable 内亚循环群
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特殊的p^(2m+1)阶capable群性质研究
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作者 李志秀 《晋中学院学报》 2015年第3期4-5,共2页
研究了特殊的p2m+1阶capable群满足capable群的条件,得到了这类群为capable群的一个充要条件.并且由这类群G构造得出了群H,H/Z(H)同构于G.
关键词 capable p^2m+1阶群 性质
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极大类的capable 3-群 被引量:2
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作者 李志秀 《安徽大学学报(自然科学版)》 CAS 北大核心 2021年第1期14-16,共3页
对于一个给定的群G,如果能有另外一个群H满足H/Z(H)■G,则称G是capable群,或称G可以充当中心商.对capable群的研究在p-群分类问题的研究中起着相当重要的作用.借助群的扩张理论,通过换位子计算,得到一些极大类3-群为capable群,并且由群... 对于一个给定的群G,如果能有另外一个群H满足H/Z(H)■G,则称G是capable群,或称G可以充当中心商.对capable群的研究在p-群分类问题的研究中起着相当重要的作用.借助群的扩张理论,通过换位子计算,得到一些极大类3-群为capable群,并且由群G构造出了群H,使得H/Z(H)■G. 展开更多
关键词 capable 3-群 循环扩张 自同构
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一些capable群
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作者 李志秀 《安徽大学学报(自然科学版)》 CAS 北大核心 2022年第6期8-11,共4页
对于一个给定的群G,如果能有另外的一个群H,使得H/Z(H)?G,则称群G是capable群,或称群G可以充当中心商.在p-群分类问题中对capable群进行的研究起着相当重要的作用.研究一些其所有的极大子群都同构且幂零类是2的capable群G,借助群的扩张... 对于一个给定的群G,如果能有另外的一个群H,使得H/Z(H)?G,则称群G是capable群,或称群G可以充当中心商.在p-群分类问题中对capable群进行的研究起着相当重要的作用.研究一些其所有的极大子群都同构且幂零类是2的capable群G,借助群的扩张理论,通过换位子计算,得到这类群是capable群的充要条件,并且由群G构造得到了群H,使得H满足H/Z(H)?G. 展开更多
关键词 capable 循环扩张 自同构
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方次数是3的capable 3群
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作者 李志秀 《扬州大学学报(自然科学版)》 CAS 北大核心 2022年第4期9-11,共3页
为研究p-群结构,运用循环扩张理论,详细讨论了方次数是3的3~5阶capable群的分类.本文所得结果为深入研究p-群结构及其他一些相关数学问题提供了依据.
关键词 capable 循环扩张 自同构
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Investigation of Capable Fault and Identification of Diffuse Seismicity
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作者 Zhang YumingInstitute of Geology,SSB,Beijing 100029,China 《Earthquake Research in China》 1996年第4期72-77,共6页
Based on the author’s experience in the siting of nuclear power plants,some important points and methods for investigation of capable fault and the identification of diffuse seismicity are discussed in the paper.
关键词 capable FAULT DIFFUSE SEISMICITY
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有关capable群的一些性质
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作者 李志秀 《山西大同大学学报(自然科学版)》 2019年第6期30-31,共2页
一个群G,如果有另外的一个群H,满足H/Z(H),称G是capable群,或称G可以充当中心商。文中得到了一类阶群p2m+1不是capable群,并且得到了一个特殊的3-群为capable群,文中由群构造出了群G,使得H/Z(H)=G.
关键词 capable 阶群
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Screening for a new Streptomyces strain capable of efficient keratin degradation 被引量:3
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作者 CHAO Ya-peng XIE Fu-hong YANG Jing LU Jing-hua QIAN Shi-jun 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2007年第9期1125-1128,共4页
Keratinous wastes could be degraded by some microorganisms in nature. Native human foot skin (NHFS) was used as sole nitrogen source to screen microorganisms with keratin-degrading capability. From approximately 200... Keratinous wastes could be degraded by some microorganisms in nature. Native human foot skin (NHFS) was used as sole nitrogen source to screen microorganisms with keratin-degrading capability. From approximately 200 strains, a strain of Streptomyces sp. strain No. 16 was found to possess the strongest keratinolytic activity, and the total activity in the culture was 110 KU/ml with specific activity of 2870 KU/mg protein (KU: keratinase unit). Substrate specificity test indicated that the crude keratinase could degrade keratin azure, human hair, cock feathers and collagen. The optimal pH of the crude keratinase ranged from 7.5 to 10 and the temperature ranged from 40℃ to 55℃. Metal chelating agent ethylenediamine tetraacetic acid obviously stimulated the keratinolytic activity but suppressed the proteolytic activity. To our knowledge, this is the first report on specific induction of keratinases by NHFS from an actinomycete. Moreover, excellent characteristics of its crude keratinase may lead to the potential application in waste treatment and recovery, poultry and leather industry, medicine, and cosmetic development. 展开更多
关键词 keratinolytic capability Streptomyces sp. native human foot skin (NHFS) KERATINASE substrate specificity
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亚循环的Capable p-群 被引量:6
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作者 李志秀 《数学的实践与认识》 CSCD 北大核心 2014年第22期232-235,共4页
给定了一个群G,若存在另外的一个群H,能够使得H/Z(H)≌G,则称G是capable群.对cable群进行研究在p-群分类问题的研究中起着相当重要的作用.完全决定了亚循环的capable p-群G.
关键词 capable 亚循环p-群
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内交换的capable p-群性质研究 被引量:3
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作者 李志秀 《数学的实践与认识》 北大核心 2016年第14期294-296,共3页
研究了内交换p-群G是capable群需要满足的条件,得到了这类群是capable群的充要条件.并由内交换p-群G构造得到了群H,使得H满足HH/Z(H)≌G.
关键词 capable 内交换p-群
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p^n(n≤4)阶capable群 被引量:1
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作者 李志秀 《数学的实践与认识》 北大核心 2015年第12期246-251,共6页
一个群G能够充当另外一个群H的中商群,称群G是capable群.考虑的问题是:对于阶为p^n(n≤4)的p-群G,哪些群是capable群?完全决定了p^n(n≤4)阶的capable p-群G.
关键词 capable p^4阶群
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Full-domain collaborative deployment method of multiple interference sources and evaluation of its deployment effect
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作者 Yue Wang Fuping Sun +2 位作者 Xian Wang Jinming Hao Kai Xiao 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2024年第2期572-595,共24页
This paper realizes the full-domain collaborative deployment of multiple interference sources of the global satellite navigation system(GNSS)and evaluates the deployment effect to enhance the ability to disturb the at... This paper realizes the full-domain collaborative deployment of multiple interference sources of the global satellite navigation system(GNSS)and evaluates the deployment effect to enhance the ability to disturb the attacker and the capability to defend the GNSS during navigation countermeasures.Key evaluation indicators for the jamming effect of GNSS suppressive and deceptive jamming sources are first created,their evaluation models are built,and their detection procedures are sorted out,as the basis for determining the deployment principles.The principles for collaboratively deploying multi-jamming sources are developed to obtain the deployment structures(including the required number,structures in demand,and corresponding positions)of three single interference sources required by collaboratively deploying.Accordingly,simulation and hardware-in-loop testing results are presented to determine a rational configuration of the collaborative deployment of multi-jamming sources in the set situation and further realize the full-domain deployment of an interference network from ground,air to space.Varied evaluation indices for the deployment effect are finally developed to evaluate the deployment effect of the proposed configuration and further verify its reliability and rationality. 展开更多
关键词 Jamming effect Multiple interference sources Collaborative deployment Effect evaluation Defense capability
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Optical trapping capability of tornado circular Pearcey beams
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作者 刘娜娜 唐晓莹 +1 位作者 刘舜禹 梁毅 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第5期401-407,共7页
We systemically investigate optical trapping capability of a kind of tornado waves on Rayleigh particles.Such tornado waves are named as tornado circular Pearcey beams(TCPBs)and produced by combining two circular Pear... We systemically investigate optical trapping capability of a kind of tornado waves on Rayleigh particles.Such tornado waves are named as tornado circular Pearcey beams(TCPBs)and produced by combining two circular Pearcey beams with different radii.Our theoretical exploration delves into various aspects,including the propagation dynamics,energy flux,orbital angular momentum,trapping force,and torque characteristics of TCPBs.The results reveal that the orbital angular momentum,trapping force,and torque of these beams can be finely tuned through the judicious manipulation of their topological charges(l_(1)and l_(2)).Notably,we observe a precise control mechanism wherein the force diminishes with|l_(1)+l_(2)|and|l_(1)-l_(2)|,while the torque exhibits enhancement by decreasing solely with|l_(1)+l_(2)|or increasing with|l_(1)-l_(2)|.These results not only provide quantitative insights into the optical trapping performance of TCPBs but also serve as a valuable reference for the ongoing development of innovative photonic tools. 展开更多
关键词 trapping capability tornado beams autofocusing
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High-rate metal-free MXene microsupercapacitors on paper substrates
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作者 Han Xue Po‐Han Huang +11 位作者 Lee‐Lun Lai Yingchun Su Axel Strömberg Gaolong Cao Yuzhu Fan Sergiy Khartsev Mats Göthelid Yan‐Ting Sun Jonas Weissenrieder Kristinn BGylfason Frank Niklaus Jiantong Li 《Carbon Energy》 SCIE EI CAS CSCD 2024年第5期94-104,共11页
MXene is a promising energy storage material for miniaturized microbatteries and microsupercapacitors(MSCs).Despite its superior electrochemical performance,only a few studies have reported MXene-based ultrahigh-rate(... MXene is a promising energy storage material for miniaturized microbatteries and microsupercapacitors(MSCs).Despite its superior electrochemical performance,only a few studies have reported MXene-based ultrahigh-rate(>1000 mV s^(−1))on-paper MSCs,mainly due to the reduced electrical conductance of MXene films deposited on paper.Herein,ultrahigh-rate metal-free on-paper MSCs based on heterogeneous MXene/poly(3,4-ethylenedioxythiophene)-poly(styrenesulfonate)(PEDOT:PSS)-stack electrodes are fabricated through the combination of direct ink writing and femtosecond laser scribing.With a footprint area of only 20 mm^(2),the on-paper MSCs exhibit excellent high-rate capacitive behavior with an areal capacitance of 5.7 mF cm^(−2)and long cycle life(>95%capacitance retention after 10,000 cycles)at a high scan rate of 1000 mV s^(−1),outperforming most of the present on-paper MSCs.Furthermore,the heterogeneous MXene/PEDOT:PSS electrodes can interconnect individual MSCs into metal-free on-paper MSC arrays,which can also be simultaneously charged/discharged at 1000 mV s^(−1),showing scalable capacitive performance.The heterogeneous MXene/PEDOT:PSS stacks are a promising electrode structure for on-paper MSCs to serve as ultrafast miniaturized energy storage components for emerging paper electronics. 展开更多
关键词 direct ink writing femtosecond laser scribing MXene on-paper microsupercapacitors PEDOT:PSS ultrahigh rate capability
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Ballistic performance of spaced multi-ply soft fabrics: Experimental and numerical investigation
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作者 Zhongwei Zhang Xiaoning Yang +4 位作者 Yuan Lin Ziming Xiong Yuhang Xiang Yi Zhou Mingyang Wang 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2024年第4期143-155,共13页
It has been reported that the ply gap influences the ballistic resistance of spaced multi-ply fabric systems,but its working mechanism was not well-understood. This paper reports the experimental and numerical approac... It has been reported that the ply gap influences the ballistic resistance of spaced multi-ply fabric systems,but its working mechanism was not well-understood. This paper reports the experimental and numerical approaches and results of an investigation on the mechanisms that enable the improved ballistic performance of spaced multi-ply systems. Penetration tests were performed over a range of impact velocities ranging from 200 m/s to 400 m/s. The results confirmed that the ply gap is beneficial to the energy absorption capability of the systems. This is because the front plies tend to absorb more energy when they are not immediately constrained by the rear plies. During a ballistic event, the gap relieves the reflection of the compressive pulse, prolonging the projectile engagement time with the front plies;on the other hand, the rear plies become increasingly less active in dissipating energy as the gap increases.When the gap is sufficiently widened to avoid any interference between the plies before the failure of the front ply, the responses of the whole system no longer vary. It was also found that the ballistic performance of the spaced systems is influenced by ply thickness, impact velocity, and the stacking order of the ply gap. 展开更多
关键词 Energy absorption capability Ply gap Ballistic performance The front ply The rear ply
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Bimetallic selenide heterostructure with directional built-in electricfield confined in N-doped carbon nanofibers for superior sodium storage with ultralong lifespan
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作者 Junying Weng Degui Zou +5 位作者 Wenyong Yuan Pengfei Zhou Minghui Ding Jin Zhou Hailin Cong Fangyi Cheng 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第4期407-416,共10页
Constructing heterostructure is considered as an effective strategy to address the sluggish electronic and ionic kinetics of anode materials for sodium ion batteries(SIBs).However,realizing the orientated growth and u... Constructing heterostructure is considered as an effective strategy to address the sluggish electronic and ionic kinetics of anode materials for sodium ion batteries(SIBs).However,realizing the orientated growth and uniform distribution of the heterostructure is still a great challenge.Herein,the regulated novel CoSe_(2)/NiSe_(2)heterostructure confined in N-doped carbon nanofibers(CoSe_(2)/NiSe_(2)@N-C)are prepared by using Co/Ni-ZIF template,in which,the CoSe_(2)/NiSe_(2)heterostructures realize uniform distribution on a micro level.Benefiting from the unique heterostructure and N-doped carbon nanofibers,the CoSe_(2)/NiSe_(2)@N-C deliveries superior rate capability and durable cycle lifespan with a reversible capacity of 400.5 mA h g^(-1)after 5000 cycles at 2 A g^(-1).The Na-ion full battery with CoSe_(2)/NiSe_(2)@N-C anode and layered oxide cathode displays a remarkable energy density of 563 W h kg^(-1)with 241.1 W kg^(-1)at 0.1 A g^(-1).The theoretical calculations disclose that the periodic and directional built-in electric-field along with the heterointerfaces of CoSe_(2)/NiSe_(2)@N-C can accelerate electrochemical reaction kinetics.The in(ex)situ experimental measurements reveal the reversible conversion reaction and stable structure of CoSe_(2)/NiSe_(2)@N-C during Na+insertion/extraction.The study highlights the potential ability of precisely controlled heterostructure to stimulate the electrochemical performances of advanced anode for SIBs. 展开更多
关键词 CoSe_(2)/NiSe_(2) heterostructure Built-in electric-field Rate capability Ultralong lifespan Sodium ion batteries
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China Flies Spacecraft Capable of Manned Trip 被引量:1
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作者 Benjamin Kang Lim 郭秀滇 《当代外语研究》 1999年第12期1-2,共2页
1999年11月2日晨6时30分,在酒泉卫星发射中心,“神舟”号试验飞船被送入太空,在太空遨游了21小时后,飞船在内蒙古自治区中部地区成功着陆!是我国自1992年实施载人航天工程以来实现的重大突破! 根据飞行和工作方式的不同,载人航天器分... 1999年11月2日晨6时30分,在酒泉卫星发射中心,“神舟”号试验飞船被送入太空,在太空遨游了21小时后,飞船在内蒙古自治区中部地区成功着陆!是我国自1992年实施载人航天工程以来实现的重大突破! 根据飞行和工作方式的不同,载人航天器分为载人飞船,载人空间站和航天飞机三类。载人飞船按乘坐人数分为单人式飞船和多人式飞船,按运行范围分为卫星式载人飞船和登月载人飞船,载人空间站又称为轨道站或航天站。可供多名航天员居住和工作。航天飞机既可作为载人飞船和空间站进行载人航天活动,又是一种可重复使用的运载器。 目前,世界上只有美国和俄罗斯掌握了载人航天技术。前苏联于1961年4月12日发射了人类第一艘载人飞船,航天员加加林乘坐飞船绕地球一周并安全返回地面,美国于1962年2月20日发射了第一艘载人飞船。这两个国家在发射载人飞船之前,都进行过多次无人飞船发射试验。 本文报道了“神舟“号飞船九霄揽月的壮举,同时还提供了一些鲜为人知的背景资料。】 展开更多
关键词 载人飞船 载人航天 航天飞机 In China Flies Spacecraft capable of Manned Trip 载人空间站
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一类p^(5)阶群的capable性质
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作者 李志秀 《数学的实践与认识》 2021年第17期181-184,共4页
研究了所有型不变量为(1,1,1,1,1)的p^(5)阶的群G是capable群需要满足的条件,得到了这类群是capable群的充要条件.并由p^(5)阶的群G构造得到了群H,使得H满足H/Z(H)≌G.
关键词 capable 型不变量
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