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σ-络合物结构计数法
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作者 韩永生 彭宇 +1 位作者 王彩兰 张新迎 《河南师范大学学报(自然科学版)》 CAS CSCD 1994年第1期111-111,共1页
σ-络合物结构计数法韩永生,彭宇,王彩兰,张新迎(河南师范大学化学系,453002,新乡)我们用Herndon提出的计算奇交替烃结构计数的方法来计算作为偶交替烃的多苯稠合芳烃,当分别进行取代反应时,所生成相应σ-络合... σ-络合物结构计数法韩永生,彭宇,王彩兰,张新迎(河南师范大学化学系,453002,新乡)我们用Herndon提出的计算奇交替烃结构计数的方法来计算作为偶交替烃的多苯稠合芳烃,当分别进行取代反应时,所生成相应σ-络合物的结构计数,具体计算σ-络合物的... 展开更多
关键词 σ-络合物 结构计数 芳香族烃
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交替烃拓扑结构计数的研究
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作者 余荣泮 杨良准 +5 位作者 刘训亭 胡启山 张自先 莫宇翔 陈琼 王成瑞 《化学研究与应用》 CAS CSCD 1994年第2期69-74,共6页
交替烃拓扑结构计数的研究余荣泮,杨良准,刘训亭,胡启山,张自先,莫宇翔,陈琼,王成瑞(武汉大学化学系武汉430072)关键词拓扑结构计数,交替烃,分子轨道分子稳定性的研究是理论化学中一个重要课题,关于这方面的工作,共... 交替烃拓扑结构计数的研究余荣泮,杨良准,刘训亭,胡启山,张自先,莫宇翔,陈琼,王成瑞(武汉大学化学系武汉430072)关键词拓扑结构计数,交替烃,分子轨道分子稳定性的研究是理论化学中一个重要课题,关于这方面的工作,共振论是富有成效的理论之一。在偶苯型... 展开更多
关键词 拓扑结构计数 交替烃 分子轨道
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交替烃代数结构计数的研究
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作者 杨良准 余荣泮 +1 位作者 莫宇翔 王成瑞 《中南民族大学学报(自然科学版)》 CAS 1995年第1期44-47,共4页
提出了一个较合理的代数结构计数(ASC)定义并分别给出了用于计算奇、偶交替烃ASC的新方法.利用自编程序计算了17个分子的ASC值,除了与文献上已发表的3个分子的数值完全一致外,其余14个分子的数值尚未见文献报道.
关键词 代数结构计数 交替烃 分子轨道
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共振论与共振结构计数
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作者 滕怡群 《烟台师范学院学报(自然科学版)》 1989年第1期91-96,共6页
本文综述了共振论的几个基本要点。对共振论结构式的计算方法进行了讨论。说明共振论在应用上具有重要价值。
关键词 共振论 共振结构计数 化学键
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关于共振结构计数
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作者 田瑞亭 《聊城师院学报(自然科学版)》 2001年第3期106-108,共3页
重点阐述了共振结构计数与非键分子轨道的关系、共振结构计数方法及其应用。
关键词 分子轨道理论 共振论 共振结构计数
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偶苯型化合物共振结构计数的计算与程序
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作者 莫宇翔 王成瑞 《计算机与应用化学》 CAS CSCD 1989年第4期316-318,共3页
近年来共振论取得了令人注目的进展。人们发现分子的稳定性、共振能等宏观性质以及分子轨道系数、键序等微观参数均与共振结构计数 SC(Structure Count)密切相关。对于交替烃,SC 可以运用零和规则手算求得,对于稠环类苯型化合物,R.L.Bro... 近年来共振论取得了令人注目的进展。人们发现分子的稳定性、共振能等宏观性质以及分子轨道系数、键序等微观参数均与共振结构计数 SC(Structure Count)密切相关。对于交替烃,SC 可以运用零和规则手算求得,对于稠环类苯型化合物,R.L.Brown 编写了FORTRAN 程序。本文采用 BASIC 语言,发展了 Brown 的设计思想,使程序简单明了且能计算有联苯情况下的 SC。 展开更多
关键词 偶苯型化合物 共振结构计数 计算
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PAH的结构参数与Diels-Alder反应 被引量:1
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作者 翟福东 徐平 戴乾圜 《北京工业大学学报》 CAS 1987年第4期31-37,共7页
以自由价指数、Dewar活性指数为结构参数,对19个PAH的结构参数与Diels-Alder反应的二级速度常数进行线性回归,得到了良好的相关性。PAH的Diels-Alder反应的反应位置可用各种结构参数推断。用自由价指数和Dewar活性指数确定了20个PAH的... 以自由价指数、Dewar活性指数为结构参数,对19个PAH的结构参数与Diels-Alder反应的二级速度常数进行线性回归,得到了良好的相关性。PAH的Diels-Alder反应的反应位置可用各种结构参数推断。用自由价指数和Dewar活性指数确定了20个PAH的反应位置,其结果与用其它结构参数确定的位置以及实验结果一致。采用共振结构计数确定反应位置,不仅与HMO参数的予言高度一致,而且方法简单。 展开更多
关键词 自由价指数 活性指数 共振结构计数 结构参数
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急性脑梗死患者血小板超微结构及相关参数变化的研究 被引量:7
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作者 江飞飞 林海燕 丁美萍 《浙江医学》 CAS 2016年第2期126-127,148,共3页
目的探讨急性脑梗死患者血小板超微结构及血小板相关参数的表达及意义。方法选择发病在6~24h的脑梗死患者30例为实验组,健康体检者30例为对照组,采用透射电镜观察血小板超微结构,比较两组患者之间的差异;采用全自动血细胞分析仪检... 目的探讨急性脑梗死患者血小板超微结构及血小板相关参数的表达及意义。方法选择发病在6~24h的脑梗死患者30例为实验组,健康体检者30例为对照组,采用透射电镜观察血小板超微结构,比较两组患者之间的差异;采用全自动血细胞分析仪检测血小板平均体积(MPV)、血小板计数(PLT),并对血小板相关参数进行分析。结果实验组及对照组的MPV分别为(9.18±0.57)、(8.76±1.32)fl,(P〈0.05),PLT分别为[(173.75±62.18)×10^9/L]、[(231.86±58.25)×10^9/L],(P〈0.05);透射电镜下,实验组患者血小板形态不规则,伪足增多,多处可见血小板聚集、融合在一起,成片状;血小板膜多处破裂;颗粒明显减少,线粒体肿胀、空泡化。对照组血小板均匀分散存在、呈圆型或椭圆型,血小板膜表面光滑,伪足突起很少,α颗粒和线粒体较多,少有空泡样改变结论急性脑梗死患者MPV升高,PLT下降,血小板超微结构显著改变,是导致脑血管急性事件的血小板病理改变基础。 展开更多
关键词 急性脑梗死 血小板 超微结构血小板平均体积血小板计数
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浅谈结构共振论
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作者 周国伟 《齐鲁师范学院学报》 1995年第4期27-30,共4页
本文简述了交替烃的零和规则,求得了非键分子轨道系数、共振结构计数和校正共振结构计数,并由此判断了体系的芳香性,结果表明与用H(?)ckel 4n+2规则判断结果是一致的。
关键词 非键分子轨道 共振结构计数 偶交替烃 结构共振 零和规则 自由基 芳香性 计数 整系数 非交替烃
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汉语个体量词“数+量+名”结构的历时形成过程 被引量:6
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作者 吴雅云 《汉语学报》 CSSCI 北大核心 2014年第3期83-90,共8页
汉语计数结构经历了"名+数→名_1+[数+名_2]→名+[数+量]→[数+量]+名"的历时形成过程。在这一过程中,计数结构的演变和个体量词的语法化是同步进行的,前者为后者提供了语法化环境,后者的语法化对前者的语序变化起到了助推作用。
关键词 计数结构 语法化 环境 扩展
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The Calculation of Parameters for DNA Kinetic Structure Based on Monte-Carlo Multiple Integrals 被引量:1
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作者 崔向军 蔡禄 《Agricultural Science & Technology》 CAS 2010年第5期5-6,16,共3页
Based on protein-DNA complex crystal structural data in up-to-date Nucleic Acid Database,the related parameters of DNA Kinetic Structure were investigated by Monte-Carlo Multiple Integrals on the base of modified DNA ... Based on protein-DNA complex crystal structural data in up-to-date Nucleic Acid Database,the related parameters of DNA Kinetic Structure were investigated by Monte-Carlo Multiple Integrals on the base of modified DNA structure statistical mechanical model,and time complexity and precision were analyzed on the calculated results. 展开更多
关键词 Monte-Carlo method Multiple integrals DNA Time complexity Precision
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关于共振论问题
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作者 何德炬 《孝感师专学报》 1992年第4期74-81,共8页
本文从共振概念出发,对它的起源和发展过程作交待,总结有11条共振规则,阐明了它在有机化学中的应用,指出了它的局限性,最后,对共振结构计数进行了讨论。
关键词 共振 共振能 结构计数 有机化学
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分组密码对称置换算法设计
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作者 罗岚 范明钰 +2 位作者 魏正耀 王光卫 瞿泽辉 《计算机应用研究》 CSCD 北大核心 2007年第1期186-187,共2页
证明了对称置换的圈结构与计数,提出并设计了一种以特定对称结构作为分组密码算法的置换部分,以减小加密算法硬件空间,提高加/解密速度。指出了分组密码的多次迭代使对称置换结构复杂化,可以选择对称置换作为分组密码算法的扩散部分来... 证明了对称置换的圈结构与计数,提出并设计了一种以特定对称结构作为分组密码算法的置换部分,以减小加密算法硬件空间,提高加/解密速度。指出了分组密码的多次迭代使对称置换结构复杂化,可以选择对称置换作为分组密码算法的扩散部分来设计。 展开更多
关键词 对称置换 分组密码算法 结构计数
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Numerical simulation of effect of bionic V-riblet non-smooth surface on tire anti-hydroplaning 被引量:4
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作者 周海超 王国林 +1 位作者 杨建 薛开鑫 《Journal of Central South University》 SCIE EI CAS CSCD 2015年第10期3900-3908,共9页
Inspired by the idea that bionic non-smooth surfaces(BNSS) can reduce fluid adhesion and resistance, and the effect of bionic V-riblet non-smooth structure arranged in tire tread pattern grooves surface on anti-hydrop... Inspired by the idea that bionic non-smooth surfaces(BNSS) can reduce fluid adhesion and resistance, and the effect of bionic V-riblet non-smooth structure arranged in tire tread pattern grooves surface on anti-hydroplaning performance was investigated by using computational fluid dynamics(CFD). The physical model of the object(model of V-riblet surface distribution, hydroplaning model) and SST k-ω turbulence model were established for numerical analysis of tire hydroplaning. With the help of a orthogonal table L16(45), the parameters of V-riblet structure design compared to the smooth structure were analyzed, and obtained the priority level of the experimental factors as well as the best combination within the scope of the experiment. The simulation results show that V-riblet structure can reduce water flow resistance by disturbing the eddy movement in boundary layers. Then, the preferred type of V-riblet non-smooth structure was arranged on the bottom of tire grooves for hydroplaning performance analysis. The results show that bionic V-riblet non-smooth structure can effectively increase hydroplaning velocity and improve tire anti-hydroplaning performance. Bionic design of tire tread pattern grooves is a good way to promote anti-hydroplaning performance without increasing additional groove space, so that tire grip performance and roll noise are avoided due to grooves space enlargement. 展开更多
关键词 TIRE anti-hydroplaning bionic non-smooth surfaces(BNSS) numerical simulation
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Research and development of a digital design system for hull structures 被引量:3
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作者 ZHAN Yi-ting JI Zhuo-shang LIU Yin-dong 《Journal of Marine Science and Application》 2007年第2期37-43,共7页
Methods used for digital ship design were studied and formed the basis of a proposed frame model suitable for ship construction modeling. Based on 3-D modeling software, a digital design system for hull structures was... Methods used for digital ship design were studied and formed the basis of a proposed frame model suitable for ship construction modeling. Based on 3-D modeling software, a digital design system for hull structures was developed. Basic software systems for modeling, modifying, and assembly simulation were developed. The system has good compatibility, and models created by it can be saved in different 3-D file formats, and 2D engineering drawings can be output directly. The model can be modified dynamically, overcoming the necessity of repeated modifications during hull structural design. Through operations such as model construction, intervention inspection, and collision detection, problems can be identified and modified during the hull structural design stage. Technologies for centralized control of the system, database management, and 3-D digital design are integrated into this digital model in the preliminary design stage of shipbuilding. 展开更多
关键词 digitalized design of ship hull structure ship CAD SOLIDWORKS
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Application of CEDA and ASPIC computer packages to the hairtail (Trichiurus japonicus) fishery in the East China Sea 被引量:14
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作者 王玉 刘群 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2013年第1期92-96,共5页
Surplus-production models are widely used in fish stock assessment and fisheries management due to their simplicity and lower data demands than age-structured models such as Virtual Population Analysis. The CEDA (catc... Surplus-production models are widely used in fish stock assessment and fisheries management due to their simplicity and lower data demands than age-structured models such as Virtual Population Analysis. The CEDA (catch-effort data analysis) and ASPIC (a surplus-production model incorporating covariates) computer packages are data-fitting or parameter estimation tools that have been developed to analyze catch-and-effort data using non-equilibrium surplus production models. We applied CEDA and ASPIC to the hairtail (Trichiurus japonicus) fishery in the East China Sea. Both packages produced robust results and yielded similar estimates. In CEDA, the Schaefer surplus production model with log-normal error assumption produced results close to those of ASPIC. CEDA is sensitive to the choice of initial proportion, while ASPIC is not. However, CEDA produced higher R 2 values than ASPIC. 展开更多
关键词 surplus production model Trichiurus japonicus catch-effort data analysis (CEDA) ASPIC sensitivity analysis
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Analysis of Flow Structure and Calculation of Drag Coefficient for Concurrent-up Gas-Solid Flow 被引量:5
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作者 杨宁 王维 +1 位作者 葛蔚 李静海 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2003年第1期79-84,共6页
This study investigates the heterogeneous structure and its influence on drag coefficient for concurrent-up gas-solid flow. The energy-minimization multi-scale (EMMS) model is modified to simulate the variation of str... This study investigates the heterogeneous structure and its influence on drag coefficient for concurrent-up gas-solid flow. The energy-minimization multi-scale (EMMS) model is modified to simulate the variation of structure parameters with solids concentration, showing the tendency for particles to aggregate to form clusters and for fluid to pass around clusters. The global drag coefficient is resolved into that for the dense phase, for the dilute phase and for the so-called inter-phase, all of which can be obtained from their respective phase-specific structure parameters. The computational results show that the drag coefficients of the different phases are quite different, and the global drag coefficient calculated from the EMMS approach is much lower than that from the correlation of Wen and Yu. The simulation results demonstrate that the EMMS approach can well describe the heterogeneous flow structure, and is very promising for incorporation into the two-fluid model or the discrete particle model as the closure law for drag coefficient. 展开更多
关键词 drag coefficient two-phase flow MULTI-SCALE flow structure two-fluid model
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Design method of pile-slab structure roadbed of ballastless track on soil subgrade 被引量:3
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作者 ZHAN Yong-xiang YAO Hai-lin JIANG Guan-lu 《Journal of Central South University》 SCIE EI CAS 2013年第7期2072-2082,共11页
Pile-slab structure roadbed is a new form of ballastless track for high speed railway. Due to lack of corresponding design code, based on the analysis of its structure characteristics and application requirements, it ... Pile-slab structure roadbed is a new form of ballastless track for high speed railway. Due to lack of corresponding design code, based on the analysis of its structure characteristics and application requirements, it is proposed to carry out load effect combination according to ultimate limit state and serviceability limit state, and the most unfavorable combination of each state is chosen to carry through design calculation for pile-slab structure. Space model of pile-slab structure can be simplified as a plane flame model, by using the orthogonal test method, and the design parameter of pile-slab structure is optimized. Moreover, based on the engineering background of Suining-Chongqing high-speed railway, the dynamic deformation characteristics of pile-slab structure roadbed are further researched by carrying on the indoor dynamic model test. The test results show that the settlement after construction of subgrade satisfies the requirement of settlement control to build ballastless track on soil subgrade for high-speed railway. Slab structure plays the role of arch shell as load is transmitted from slab to pile, and the vertical dynamic stress of subgrade soil is approximately of "K" form distribution with the depth. The distribution of pile stress is closely related to soil characteristics, which has an upset triangle shape where the large dynamic stress is at the top. Pile compared with soil shares most dynamic stress. Pile structure expands the depth of the dynamic response of subgrade has limited effect on dynamic response. These results can provide subgrade. and improves the stress of subgrade soil, and the speed of train scientific basis for pile-slab structure roadbed used on soil 展开更多
关键词 soil subgrade ballastless track pile-slab structure roadbed load combination dynamic model test
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The rough representation and measurement of quotient structure in algebraic quotient space model 被引量:5
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作者 陈林书 Wang Jiayang 《High Technology Letters》 EI CAS 2017年第3期293-297,共5页
Granular computing is a very hot research field in recent years. In our previous work an algebraic quotient space model was proposed,where the quotient structure could not be deduced if the granulation was based on an... Granular computing is a very hot research field in recent years. In our previous work an algebraic quotient space model was proposed,where the quotient structure could not be deduced if the granulation was based on an equivalence relation. In this paper,definitions were given and formulas of the lower quotient congruence and upper quotient congruence were calculated to roughly represent the quotient structure. Then the accuracy and roughness were defined to measure the quotient structure in quantification. Finally,a numerical example was given to demonstrate that the rough representation and measuring methods are efficient and applicable. The work has greatly enriched the algebraic quotient space model and granular computing theory. 展开更多
关键词 granular computing algebraic quotient space model quotient structure upper(lower) congruence relation
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3D structure parameterization design and modeling for irregular structure of stope bottom 被引量:3
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作者 曾庆田 Wang Liguan 《High Technology Letters》 EI CAS 2016年第1期55-62,共8页
Stope mining design is a very important and complicated task in daily production design and technical management of an underground mine.Based on workface technology and human-computer interaction technology,this study... Stope mining design is a very important and complicated task in daily production design and technical management of an underground mine.Based on workface technology and human-computer interaction technology,this study introduces a method of 3D parametric design for the irregular structure of stope bottoms,and focuses on solving technical problems in surface modeling of stope bottom structure.Optimization of the minimum span length algorithm(MSLA) and the shortest path search algorithm(SPSA) is conducted to solve the problem of contour-line based instant modeling of stope bottom structures,which makes possible the 3D parametric design for irregular structure of stope bottom.Implementation process and relevant methods of the proposed algorithms are also presented.Feasibility and reliability of the proposed modeling method are testified in a case study.In practice,the proposed 3 D parameterization design method for irregular structure stope bottom proves to be very helpful to precise 3D parametric design.This method is capable of contributing to improved efficiency and precision of stope design,and is worthy of promotion. 展开更多
关键词 irregular stope bottom structure STOPE structure parameterization design surface reconstruction modeling
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