检索结果-南通市图书馆

Investigations of spectroscopic parameters and molecular constants for X^1Σ_g^+, w^3△_u, and W^1△_u electronic states of P_2 molecule

在线全文

学校读者我要写书评

暂无评论

Chinese Physics B 2012年第2期21卷 235-242页

作者： Wang Jie-Min Feng heng-Qiang Sun Jin-Feng shi de-heng department of Physics&Electronic Information Luoyang Normal CollegeLuoyang 471022China College of Physics&Information Engineering Henan Normal UniversityXinxiang 453007China

The potential energy curves （PECs） of three low-lying electronic states （X1 ∑g^＋, w^3 △u, and W1 △u） of P2 molecule are investigated using the full valence complete active space self-consistent field （CASSCF） method followed by the highly accurate valence internally contracted multireference configuration interaction （MRCI） approach in conjunction with the correlation-consistent basis set in the valence range. The PECs of the electronic states involved are modified by the Davidson correction and extrapolated to the complete basis set （CBS） limit. With these PECs, the spectroscopic parameters of the three electronic states are determined and compared in detail with the experimental data. The comparison shows that excellent agreement exists between the present results and the available experimental data. The complete vibrational states are computed for the W3Au and WlAu electronic states when the rotational quantum number J equals zero and the vibrational level G（v）, the inertial rotation constant By, and the centrifugal distortion constant Dv of the first 30 vibrational states are reported, which accord well with the experimental data. The present results show that the two-point extrapolation scheme can obviously improve the quality of spectroscopic parameters and molecular constants.

关键词： spectroscopic parameter molecular constant Davidson correction extrapolation

A Modified Potential Method for Electrons Scattering Total Cross Section Calculations on Several Molecules at 30 ～ 5000 eV： CF4, CCl4, CFCl3, CF2Cl2, and CF3Cl

在线全文

学校读者我要写书评

暂无评论

Communications in Theoretical Physics 2006年第4期45卷 697-701页

作者： MA heng shi de-heng SUN Jin-Feng LIU Yu-Fang ZHU Zun-Lue department of Physics Henan Normal University Xinxiang 453007 China department of Foundation the First Aeronautical College of Air Force Xinyang 464000 China

A complex optical model potential modified by the concept of bonded atom, which takes into consideration the overlapping effect of electron clouds between two atoms in a molecule, is employed to calculate the total cross sections （TCS5） for electrons scattering from several molecules （CF4, CCl4, CFCl3, CF2 Cl2, and CF3 Cl） over an incident energy range 30 - 5000 eV using the additivity rule model at Hartre-Fock level. The quantitative TCS5 are compared with those obtained by experiments and other theories wherever available, and good agreement is obtained above 100 eV. It is shown that the modified potential can successfully calculate the TCS5 of electron-molecule scattering over a wide energy range, especially at lower energies.

关键词： total cross section additivity rule atomic and molecular collision

Concise extraction and characterization of the pore-throat network in unconventional hydrocarbon reservoirs: A new perspective

在线全文

学校读者我要写书评

暂无评论

Petroleum Science 2024年第3期21卷 1474-1487页

作者： Shu-heng Du Yong-Min shi State Key Laboratory of Nonlinear Mechanics Institute of MechanicsChinese Academy of SciencesBeijing100190China School of Engineering Science University of Chinese Academy of SciencesBeijing100049China School of Earth and Space Sciences Peking UniversityBeijing100871China

In this study,a new image-based method for the extraction and characterization of pore-throat network for unconventional hydrocarbon storage and exploitation is proposed.“Pore-throat solidity”,which is analogous to particle solidity,and a new method for automatic identification of pores and throats in tight sandstone oil reservoirs are ***,the“pore-throat combination”and“pure pore”are defined and distinguished by drawing the cumulative probability curve of the pore-throat solidity and by selecting an appropriate cutoff *** the discrete grid set is recognized as a pore-throat combination,Legendre ellipse fitting and minimum Feret diameter are *** the pore and throat grid sets are identified as pure pores,the pore diameter can be directly *** the new method,the analytical results for the physical parameters and pore radius agree well with most prior *** results comparing the maximum ball and the new model could also prove the accuracy of the latter's in micro and nano *** new model provides a more practical theoretical basis and a new calculation method for the rapid and accurate evaluation of the complex processes of oil migration.

关键词： Hydrocarbon exploitation Pore Throat Porous media Identification

Interplay of RNA-binding proteins controls germ cell development in zebrafish

在线全文

学校读者我要写书评

暂无评论

Journal of Genetics and Genomics 2024年第9期51卷 889-899页

作者： de-Li shi Laboratory of developmental Biology CNRS-UMR7622Institut de Biologie Paris-Seine(IBPS)Sorbonne University75005 ParisFrance

The specification of germ cells in zebrafish mostly relies on an inherited mechanism by which localized maternal determinants,called germ plasm,confer germline fate in the early *** studies have partially allowed the identification of key regulators governing germ plasm formation and subsequent germ cell ***-binding proteins,acting in concert with other germ plasm components,play essential roles in the organization of the germ plasm and the specification,migration,maintenance,and differentiation of primordial germ *** loss of their functions impairs germ cell formation and causes sterility or sexual *** is emerging that they instruct germline development through differential regulation of mRNA fates in somatic and germ ***,the challenge remains to decipher the complex interplay of maternal germ plasm components in germ plasm compartmentalization and germ cell *** failure to control the developmental outcome of germ cells disrupts the formation of gametes,it is important to gain a complete picture of regulatory mechanisms operating in the germ cell *** review sheds light on the contributions of RNA-binding proteins to germ cell development in zebrafish and highlights intriguing questions that remain open for future investigation.

关键词： Germplasm Primordialgerm cell Germlinestem cell Gametogenesis Zebrafish RNA-binding protein Posttranscriptional gene expression Translational activation and repression

Mastering air combat game with deep reinforcement learning

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

defence Technology（防务技术） 2024年第4期34卷 295-312页

作者： Jingyu Zhu Minchi Kuang Wenqing Zhou heng shi Jihong Zhu Xu Han department of Precision Instruments Tsinghua UniversityBeijing 100084China department of Computer Science and Technology Tsinghua UniversityBeijing 100084China Chengdu Aircraft design&Research Institute Aviation Industry Corporation of ChinaChengdu 610000China

Reinforcement learning has been applied to air combat problems in recent years,and the idea of curriculum learning is often used for reinforcement learning,but traditional curriculum learning suffers from the problem of plasticity loss in neural *** loss is the difficulty of learning new knowledge after the network has *** this end,we propose a motivational curriculum learning distributed proximal policy optimization(MCLDPPO)algorithm,through which trained agents can significantly outperform the predictive game tree and mainstream reinforcement learning *** motivational curriculum learning is designed to help the agent gradually improve its combat ability by observing the agent's unsatisfactory performance and providing appropriate rewards as a ***,a complete tactical maneuver is encapsulated based on the existing air combat knowledge,and through the flexible use of these maneuvers,some tactics beyond human knowledge can be *** addition,we designed an interruption mechanism for the agent to increase the frequency of decisionmaking when the agent faces an *** the number of threats received by the agent changes,the current action is interrupted in order to reacquire observations and make decisions *** the interruption mechanism can significantly improve the performance of the *** simulate actual air combat better,we use digital twin technology to simulate real air battles and propose a parallel battlefield mechanism that can run multiple simulation environments simultaneously,effectively improving data *** experimental results demonstrate that the agent can fully utilize the situational information to make reasonable decisions and provide tactical adaptation in the air combat,verifying the effectiveness of the algorithmic framework proposed in this paper.

关键词： Air combat MCLDPPO Interruption mechanism Digital twin Distributed system

Analytical Potential Energy Function,Spectroscopic Constants and Vibrational Levels for A^1E_u^+ State of Dimer ~7Li_2

在线全文

学校读者我要写书评

暂无评论

Communications in Theoretical Physics 2007年第12期48卷 1081-1087页

作者： shi de-heng~1 MA heng~1 SUN Jin-Feng~(1,2)and ZHU Zun-Lue~1~1 College of Physics & Information Engineering,Henan Normal University,Xinxiang 453007,China~2 department of Physics & Electron Science,Luoyang Normal University,Luoyang 471022,China College of Physics & Information Engineering Henan Normal University Xinxiang 453007 China department of Physics & Electron Science Luoyang Normal University Luoyang 471022 China

The symmetry-adapted-duster configuration-interaction method is used to investigate the spectroscopicproperties of ~7Li_2(A^1∑_u^+) over the internuclear distance ranging from 2.4ao to *** complete potential energycurves are calculated at numbers of basis *** the ab initio calculated points are fitted to the analytic MurrellSorbie function and then employed to compute the spectroscopic *** comparison,the spectroscopic constantsreproduced by the potential attained at D95(3df,3pd) are found to be very close to the experiments,a^d the values (T_e,D_e,R_e,ω_e,ω_eχ_e,α_e and B_e) are of 1.732 93 eV,1.161 36 eV,0.313 27 nm,251.95 cm^(-1),1.623 cm^(-1),0.005 35 cm^(-1),and0.490 cm^(-1),*** the potential obtained at D95(3df,3pd),the totally 75 vibrational states are found whenJ=*** vibrational levels,the classical turning points and the inertial rotation constants of the first 68 vibrationalstates are calculated for the first time and compared with the available *** agreement is *** centrifugal distortion constants of the first 32 vibrational states are also reported for the first *** reasonabledissociation limit for ~7Li_2(A^1∑_u^+) is deduced using the calculated results at present.

关键词： analytic potential energy function harmonic frequency dissociation energy vibrational level classical turning point

~7Li_2分子2~3Σ_g^+激发态的解析势能函数、谐振频率及振动能级

在线全文

学校读者我要写书评

暂无评论

物理学报 2007年第4期56卷 2085-2091页

作者：施德恒孙金锋马恒朱遵略信阳师范学院物理电子工程学院信阳464000 河南师范大学物理与信息工程学院新乡453007

使用Gaussian03程序包中的“对称性匹配簇/对称性匹配簇-组态相互作用”方法,利用多个基组对7Li2分子23Σg+态的平衡几何进行了优化计算.同时,在优化得到的平衡位置附近、于同一条件下通过精细的单点能扫描,获得了相应基组下的平衡核间... 详细信息

使用Gaussian03程序包中的“对称性匹配簇/对称性匹配簇-组态相互作用”方法,利用多个基组对7Li2分子23Σg+态的平衡几何进行了优化计算.同时,在优化得到的平衡位置附近、于同一条件下通过精细的单点能扫描,获得了相应基组下的平衡核间距.发现两者的结果不一致,对不一致的原因进行了解释.分析表明,由单点能扫描得到的平衡核间距应更为合理.同时也得出了6-311++G(3df,3pd),6-311++G(2df,2pd)及6-311++G(2df,pd)基组均为较优基组的结论.于2.5a0—37a0的范围内利用6-311++G(3df,3pd)基组进行单点能扫描并使用最小二乘法拟合出了该态的解析势能函数.利用解析势能函数的物理意义并结合Rydberg-Klein-Rees方法,计算出了其相应的谐振频率,进而计算了其他光谱常数.为便于比较和分析,对基态也进行了相应的计算.利用得到的解析势能函数,对23Σg+态的振动能级及振动经典转折点也进行了计算.

关键词：势能函数谐振频率振动能级 Murrell-Sorbie函数

Recyclable High-performance Carbon Fiber Reinforced Epoxy Composites Based on Dithioacetal Covalent Adaptive Network

在线全文

学校读者我要写书评

暂无评论

Chinese Journal of Polymer Science 2024年第10期42卷 1514-1524,I0011页

作者： Gui-Lian shi Ting-Cheng Li Dao-Hong Zhang Jun-heng Zhang Key Laboratory of Catalysis and Energy Materials Chemistry of Ministry of Education&Hubei Key Laboratory of Catalysis and Materials Science Hubei R&D Center of Hyperbranched Polymers Synthesis and ApplicationsSouth-Central Minzu UniversityWuhan430074China State Key Laboratory of New Textile Materials and Advanced Processing Technologies Wuhan Textile UniversityWuhan430200China Ministry-of-Education Key Laboratory for the Green Preparation and Application of Functional Materials Hubei UniversityWuhan430062Chin

Recycling of carbon fiber reinforced composites is important for sustainable development and the circular *** the use of dynamic chemistry,developing high-strength recyclable CFRPs remains a major challenge due to the mutual exclusivity between the dynamic and mechanical properties of ***,we developed a high-strength recyclable epoxy resin(HREP)based on dynamic dithioacetal covalent adaptive network using diglycidyl ether bisphenol A(DGEBA),pentaerythritol tetra(3-mercapto-propionate)(PETMP),and vanillin epoxy resin(VEPR).At high temperatures,the exchange reaction of thermally activated dithioacetals accelerated the rearrangement of the network,giving it significant reprocessing ***,HREP exhibited excellent solvent resistance due to the increased cross-linking *** this high-strength recyclable epoxy resin as the matrix and carbon fiber modified with hyperbranched ionic liquids(HBP-AMIM+PF6-)as the reinforcing agent,high performance CFRPs were successfully *** tensile strength,interfacial shear strength(IFSS)and interlaminar shear strength(ILSS)of the optimized formulation(HREP20/CF-HBPPF6)were 1016.1,70.8 and 76.0 MPa,*** addition,the CFRPs demonstrated excellent solvent and acid/*** CFRPs could completely degrade within 24 h in DMSO at 140℃,and the recycled CF still maintained the same tensile strength and ILSS as the original after multiple degradation cycles.

关键词： Epoxy resin Hyperbranched ionic liquid Recycling Carbon fiber Composites

Preparation and Rheological Characterization of Long Chain Branching Polyglycolide

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Chinese Journal of Polymer Science 2024年第8期42卷 1177-1184页

作者： Wei-Lin Liu Ming-Fu Lyu heng-Yuan Zhang Jian-Ye Liu shi-Jun Zhang Beijing University of Chemical Technology Beijing 100029China SINOPEC(Beijing)Research Institute of Chemical Industry Co. Ltd.Beijing 100013China

The long chain branching(LCB)polyglycolide(PGA)was successfully prepared by the successive reactions of the terminal hydroxyl groups of PGA with triglycidyl isocyanurate(TGIC)and pyromellitic dianhydride(PMDA).The influence of LCB produced by functional group reaction on rheological and crystallization behavior was studied and discussed through linear rheology,uniaxial elongation and DSC(differential scanning calorimetry).The much higher viscosity and the more notable strain hardening behavior of modified PGA indicates the LCB with high degree of entanglements are *** melt strength of PGA is finally improved greatly and can make su re that the supercritical CO_(2)foaming can be carried out successfully.

关键词： Polyglycolide(PGA) Long chain branching(LCB) Rheology