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Matching Source Code Using Abstract Syntax Trees in Version Control Systems 被引量:1
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作者 Jonathan van den Berg Hirohide Haga 《Journal of Software Engineering and Applications》 2018年第6期318-340,共23页
Software projects are becoming larger and more complicated. Managing those projects is based on several software development methodologies. One of those methodologies is software version control, which is used in the ... Software projects are becoming larger and more complicated. Managing those projects is based on several software development methodologies. One of those methodologies is software version control, which is used in the majority of worldwide software projects. Although existing version control systems provide sufficient functionality in many situations, they are lacking in terms of semantics and structure for source code. It is commonly believed that improving software version control can contribute substantially to the development of software. We present a solution that considers a structural model for matching source code that can be used in version control. 展开更多
关键词 VERSION Control Source Code MATCHING abstract SYNTAX Tree STRUCTURED Representation
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Verifying the accuracy of interlocking tables for railway signalling systems using abstract state machines 被引量:1
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作者 Basri Tugcan Celebi Ozgur Turay Kaymakci 《Journal of Modern Transportation》 2016年第4期277-283,共7页
Railway transportation system is a critical sector where design methods and techniques are defined by international standards in order to reduce possible risks to an acceptable minimum level. CENELEC 50128 strongly re... Railway transportation system is a critical sector where design methods and techniques are defined by international standards in order to reduce possible risks to an acceptable minimum level. CENELEC 50128 strongly recommends the utilization of finite state machines during system modelling stage and formal proof methods during the verifi- cation and testing stages of control algorithms. Due to the high importance of interlocking table at the design state of a sig- nalization system, the modelling and verification of inter- locking tables are examined in this work. For this purpose, abstract state machines are used as a modelling tool. The developed models have been performed in a generalized structure such that the model control can be done automatically for the interlocking systems. In this study, NuSMV is used at the verification state. Also, the consistency of the developed models has been supervised through fault injection. The developed models and software components are applied on a real railway station operated by Metro Istanbul Co. 展开更多
关键词 Model checking - abstract state machines Interlocking
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Research on the Automatic Pattem Abstraction and Recognition Methodology for Large-scale Database System based on Natural Language Processing 被引量:1
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作者 RongWang Cuizhen Jiao Wenhua Dai 《International Journal of Technology Management》 2015年第9期125-127,共3页
In this research paper, we research on the automatic pattern abstraction and recognition method for large-scale database system based on natural language processing. In distributed database, through the network connec... In this research paper, we research on the automatic pattern abstraction and recognition method for large-scale database system based on natural language processing. In distributed database, through the network connection between nodes, data across different nodes and even regional distribution are well recognized. In order to reduce data redundancy and model design of the database will usually contain a lot of forms we combine the NLP theory to optimize the traditional method. The experimental analysis and simulation proves the correctness of our method. 展开更多
关键词 Pattern abstraction and Recognition Database system Natural Language Processing.
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An Existent Condition of Error Bounds for Abstract Linear Inequality System
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作者 ZHAI Zhi-chun 《Chinese Quarterly Journal of Mathematics》 CSCD 北大核心 2008年第3期344-348,共5页
We consider the abstract linear inequality system (A, C, b) and give a sufficient condition for the system (A, C, b) to have an error bound, which extends the previous result.
关键词 error bounds abstract linear inequality system quasi*-Bishop-Phelps cones
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Conversion of Object Oriented System into Software Product Line with Delta Modeling Abstract Behavioral Specification
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作者 Ricky Timothy Gultom Maya Retno Ayu Setyautami Iis Solichah 《Journal of Computer and Communications》 2014年第2期85-90,共6页
This article contains a system conversion from object oriented design into Software Product Line (SPL) using delta modeling of Abstract Behavioral Specification (ABS). ABS is a modeling language which targets system w... This article contains a system conversion from object oriented design into Software Product Line (SPL) using delta modeling of Abstract Behavioral Specification (ABS). ABS is a modeling language which targets system with high level of variety and supports SPL development with delta modeling. The case study of this thesis is a digital library system called Library Automation and Digital Archive (LONTAR). Originally, LONTAR only uses SOAP-based web service. With ABS, LONTAR will be converted into SPL and implement another web service called REST. The motivation of this conversion of LONTAR from object oriented into SPL is because it is easier to develop system with ABS than using regular object oriented. Product definition in ABS is relatively easier than creating a new subclass and do customization to make it works well. 展开更多
关键词 system CONVERSION abstract BEHAVIORAL SPECIFICATION DELTA MODELING Software Product line Object Oriented
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Exploring Nominalization in English Abstracts of Applied Linguistics Research Articles:A Comparative Study Between Chinese and International Journals
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作者 Gong Yingrui Zhao Yibu 《Contemporary Social Sciences》 2024年第4期122-142,共21页
Researchers around the world strive to communicate new knowledge,primarily via publication,with the abstract being crucial in conveying core insights.Previous research has generally analyzed the discourse features of ... Researchers around the world strive to communicate new knowledge,primarily via publication,with the abstract being crucial in conveying core insights.Previous research has generally analyzed the discourse features of abstracts from a macro perspective and often employed either outdated texts,such as those over a decade old,or papers written by authors with lower English academic writing proficiency as research material.In this study,we analyzed forty abstracts from leading journals in applied linguistics,evenly split between Chinese and international journals.It revealed that the use of nominalization in abstracts by Chinese and international scholars showed similarities due to the universal academic requirement for conciseness.However,due to cultural and educational differences,each group differed in their respective language choices and nominalization usage.By analyzing the application of nominalization in different cultural contexts,the results of our study offered practical suggestions for crafting abstracts that effectively convey information,thereby,contributing to the broader academic community. 展开更多
关键词 NOMINALIZATION abstractS comparative study applied linguistics
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Embodied Meaning in Comprehending Abstract Chinese Counterfactuals
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作者 Xueyan LI Yahui ZHAO +1 位作者 Huili WANG Xue ZHANG 《Chinese Journal of Applied Linguistics》 2024年第3期414-432,524,共20页
Embodied cognition theories propose that language comprehension triggers a sensorimotor system in the brain.However,most previous research has paid much attention to concrete and factual sentences,and little emphasis ... Embodied cognition theories propose that language comprehension triggers a sensorimotor system in the brain.However,most previous research has paid much attention to concrete and factual sentences,and little emphasis has been put on the research of abstract and counterfactual sentences.The primary challenges for embodied theories lie in elucidating the meanings of abstract and counterfactual sentences.The most prevalent explanation is that abstract and counterfactual sentences are grounded in the activation of a sensorimotor system,in exactly the same way as concrete and factual ones.The present research employed a dual-task experimental paradigm to investigate whether the embodied meaning is activated in comprehending action-related abstract Chinese counterfactual sentences through the presence or absence of action-sentence compatibility effect(ACE).Participants were instructed to read and listen to the action-related abstract Chinese factual or counterfactual sentences describing an abstract transfer word towards or away from them,and then move their fingers towards or away from them to press the buttons in the same direction as the motion cue of the transfer verb.The action-sentence compatibility effect was observed in both abstract factual and counterfactual sentences,in line with the embodied cognition theories,which indicated that the embodied meanings were activated in both action-related abstract factuals and counterfactuals. 展开更多
关键词 action-sentence compatibility effect EMBODIMENT abstract COUNTERFACTUALS language comprehension
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A Comparative Analysis of Syntactic Complexity in Applied Linguistics Abstracts Written by Chinese Novice Writers and Native English Advanced Writers
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作者 Mingming Zhao Tianshuang Ge 《Open Journal of Applied Sciences》 2024年第1期1-26,共26页
The rhetorical structure of abstracts has been a widely discussed topic, as it can greatly enhance the abstract writing skills of second-language writers. This study aims to provide guidance on the syntactic features ... The rhetorical structure of abstracts has been a widely discussed topic, as it can greatly enhance the abstract writing skills of second-language writers. This study aims to provide guidance on the syntactic features that L2 learners can employ, as well as suggest which features they should focus on in English academic writing. To achieve this, all samples were analyzed for rhetorical moves using Hyland’s five-rhetorical move model. Additionally, all sentences were evaluated for syntactic complexity, considering measures such as global, clausal and phrasal complexity. The findings reveal that expert writers exhibit a more balanced use of syntactic complexity across moves, effectively fulfilling the rhetorical objectives of abstracts. On the other hand, MA students tend to rely excessively on embedded structures and dependent clauses in an attempt to increase complexity. The implications of these findings for academic writing research, pedagogy, and assessment are thoroughly discussed. 展开更多
关键词 Syntactic Complexity Rhetorical Functions Research Article abstract L2 Academic Writing
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关于MEDLINE-Abstracts文献的语法规则的构建与实现 被引量:1
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作者 王剑辉 姜龙滨 穆宝良 《西安科技大学学报》 CAS 北大核心 2007年第1期111-114,共4页
以MEDLINE-Abstracts为研究对象,对其语言特点进行了统计和分析,采用计算机语言学方法,使用XDOC工具,构建并实现了对MEDLINE-Abstracts文献处理有效的英语语法规则。本文作者所开发的应用程序软件对减少文献分析中的多态性问题也是非常... 以MEDLINE-Abstracts为研究对象,对其语言特点进行了统计和分析,采用计算机语言学方法,使用XDOC工具,构建并实现了对MEDLINE-Abstracts文献处理有效的英语语法规则。本文作者所开发的应用程序软件对减少文献分析中的多态性问题也是非常有效和实用的。XDOC是一个处理德文和英文文献有效的工具,对汉语文献的处理也具有积极的借鉴意义。 展开更多
关键词 语言处理 MEDLINE—abstracts语言 实现 语法规则
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CAB ABSTRACTS光盘数据库中的中国文献研究 被引量:3
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作者 张永红 《情报杂志》 CSSCI 北大核心 2000年第5期58-60,共3页
运用文献统计学和文献计量学的方法,对世界第一大国际权威农业文献检索系统CAB AB-STRACTS光盘数据库在1972-1998年4月间收录的中国农业科技论文的数量、原文语种以及英文摘要附有率进行了研究,并就如何提高我国农业文献在国际权威检索... 运用文献统计学和文献计量学的方法,对世界第一大国际权威农业文献检索系统CAB AB-STRACTS光盘数据库在1972-1998年4月间收录的中国农业科技论文的数量、原文语种以及英文摘要附有率进行了研究,并就如何提高我国农业文献在国际权威检索系统中的收录量提出了建议。 展开更多
关键词 CAB abstractS CAB文摘数据库 中国 农业文献
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Experimental and Theoretical Study of Hydrogen Atom Abstraction from C2H6 and C4H10 by Zirconium Oxide Clusters Anions 被引量:1
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作者 马嘉璧 吴晓楠 +2 位作者 赵艳霞 丁迅雷 何圣贵 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 2010年第2期133-137,I0001,共6页
The reactions of anionic zirconium oxide clusters ZrxOy- with C2H6 and C4H10 are investi-gated by a time of flight mass spectrometer coupled with a laser vaporization cluster source.Hydrogen containing products Zr2O5H... The reactions of anionic zirconium oxide clusters ZrxOy- with C2H6 and C4H10 are investi-gated by a time of flight mass spectrometer coupled with a laser vaporization cluster source.Hydrogen containing products Zr2O5H- and Zr3O7H- are observed after the reaction. Den-sity functional theory calculations indicate that the hydrogen abstraction is favorable in the reaction of Zr2O5- with C2H6, which supports that the observed Zr2O5H- and Zr3O7H- are due to hydrogen atom abstraction from the alkane molecules. This work shows a newpossible pathway in the reaction of zirconium oxide cluster anions with alkane molecules. 展开更多
关键词 Time of flight mass spectrometry Zirconium oxide cluster anion Reactivity Density functional theory Hydrogen atom abstraction
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基于SystemC的嵌入式系统设计的描述模型 被引量:1
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作者 栾静 顾君忠 《计算机科学》 CSCD 北大核心 2005年第8期209-212,共4页
系统建模是嵌入式系统设计的关键步骤,其好坏直接影响着设计的质量和产品的上市时间。已有多种建模方案,但每种都有其局限性。本文提出一种由5层模型组成的嵌入式系统设计的模型框架。它能够从需求描述开始,建立CDM功能模型,经一致性验... 系统建模是嵌入式系统设计的关键步骤,其好坏直接影响着设计的质量和产品的上市时间。已有多种建模方案,但每种都有其局限性。本文提出一种由5层模型组成的嵌入式系统设计的模型框架。它能够从需求描述开始,建立CDM功能模型,经一致性验证,满足设计要求后映射到SystemC抽象模型上。利用SystemC的硬件描述特征和仿真库,增加设计细节,分层细化模型并进行验证,最后达到软硬件的协同设计和综合实现的目的。 展开更多
关键词 嵌入式系统 分层抽象模型 systemC 嵌入式系统设计 描述模型 一致性验证 系统建模 关键步骤 上市时间 模型框架
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Photochemical Hydrogen Abstraction and Electron Transfer Reactions of Tetrachlorobenzoquinone with Pyrimidine Nucleobases
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作者 刘坤辉 吴丽丹 +3 位作者 邹笑然 杨文 杜谦 苏红梅 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 2011年第5期580-585,I0004,共7页
Pentachlorophenol, a widespread environmental pollutant that is possibly carcinogenic to humans, is metabolically oxidized to tetrachloroquinone (TCBQ) which can result in DNA damage. We have investigated the photoc... Pentachlorophenol, a widespread environmental pollutant that is possibly carcinogenic to humans, is metabolically oxidized to tetrachloroquinone (TCBQ) which can result in DNA damage. We have investigated the photochemical reaction dynamics of TCBQ with two pyrimidine type nucleobases (thymine and uracil) upon UVA (355 ran) excitation using the technique of nanosecond time-resolved laser flash photolysis. It has been found that 355 nm excitation populates TCBQ molecules to their triplet state 3TCBQ*, which are highly reactive towards thymine or uracil and undergo two parallel reactions, the hydrogen abstraction and electron transfer, leading to the observed photoproducts of TCBQH. and TCBQ.- in transient absorption spectra. The concomitantly produced nucleobase radicals and radical cations are expected to induce a series of oxidative or strand cleavage damage to DNA afterwards. By characterizing the photochemical hydrogen abstraction and electron transfer reactions, our results provide potentially important molecular reaction mechanisms for understanding the carcinogenic effects of pentachlorophenol and its metabolites TCBQ. 展开更多
关键词 Tetrachlorobenzoquinone THYMINE URACIL Triplet state Hydrogen abstraction Electron transfer Laser flash photolysis
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Laser Flash Photolysis Mechanism of Anthraquinone-2-Sodium Sulfonate in Pyridine Ionic Liquid/Water Mixed System
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作者 朱光来 张良伟 +3 位作者 刘艳成 崔执凤 许新胜 吴国忠 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 2016年第1期140-146,I0003,共8页
The photochemical reaction process of anthraquinone-2-sodium sulfonate (AQS) in the mixture of water (H2O) and N-butylpyridinium tetrafluoroborate ([BPy] [BF4]) was studied using the laser flash photolysis techn... The photochemical reaction process of anthraquinone-2-sodium sulfonate (AQS) in the mixture of water (H2O) and N-butylpyridinium tetrafluoroborate ([BPy] [BF4]) was studied using the laser flash photolysis technique. Experimental results show that the excited triplet of AQS (3AQS*) could react rapidly with H2O and the transient absorption spectra greatly changed by increasing the volume fraction of the ionic liquid (VIL) in [BPy][BF4]/H2O mixtures. The absorbance at 510 nm increased gradually with increasing VIL when 0〈VIL〈0.1. By contrast, the absorbance decreased gradually when VIL〉0.1. Otherwise, the absorbance of the band near 380 nm steadily increased. The apparent kinetic parameters of transient species B and ^3AQS* are obtained approximately. 3AQS* abstracting hydrogen from [BPy]+ was also explored. It was deduced that the 350-420 nm band was the superposition of the peaks of 3AQS* and AQSH'. The two reactions of 3AQS* with [BPy][BF4] and H2O are a pair of competitive reactions. We also concluded that the entire reaction processes slow down in the case of high [BPy] [BF4] concentrations. 展开更多
关键词 Laser flash photolysis Anthraquinone-2-sodium sulfonate Ionic liquids Tran- sient absorption Hydrogen abstraction
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Problem of interoperability in semantic web service system
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作者 满君丰 彭三城 +1 位作者 向剑伟 胡永祥 《Journal of Southeast University(English Edition)》 EI CAS 2006年第3期306-310,共5页
In order to fully realize semantic interoperability among distributed and heterogeneous applications on the web, a set of effective interoperability mechanisms is presented. This mechanism adopts service interactive i... In order to fully realize semantic interoperability among distributed and heterogeneous applications on the web, a set of effective interoperability mechanisms is presented. This mechanism adopts service interactive interfaces (SII) and service aggregative interfaces (SAI) modeled with abstract state machine (ASM) to abstractly describe the behavior of the invoked web service instances, which makes business processing accurately specify tasks and effectively solves the problems of communication and collaboration between service providers and service requesters. The mechanism also uses appropriate mediators to solve the problems of information and coinmunication incompatibility during the course of service interaction, which is convenient for service interoperability, sharing and integration. The mechanism' s working principle and interoperability implementation are illustrated by a use case in detail. 展开更多
关键词 semantic services-oriented architecture abstract state machine service interface INTEROPERABILITY
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REPRESENTATION PROPERTIES OF ABSTRACT DEFAULT REASONING FRAMEWORKS
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作者 曹子宁 毛宇光 石纯一 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 2006年第3期214-221,共8页
presented The conceptions of abstract default reasoning frameworks (ADRFs) and D-consequence relations are Based on representation properties of D-consequence relations, it proves that any cumulative nonmonotonic co... presented The conceptions of abstract default reasoning frameworks (ADRFs) and D-consequence relations are Based on representation properties of D-consequence relations, it proves that any cumulative nonmonotonic consequence relation with the connective-free form can be represented by ADRFs. 展开更多
关键词 abstract default reasoning framework representation property nonmonotonie reasoning
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Subspaces for weak mild solutions of the second order abstract differential equation
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作者 王梅英 《Journal of Southeast University(English Edition)》 EI CAS 2007年第2期313-316,共4页
The topic on the subspaces for the polynomially or exponentially bounded weak mild solutions of the following abstract Cauchy problem d^2/(dr^2)u(t,x)=Au(t,x);u(0,x)=x,d/(dt)u(0,x)=0,x∈X is studied, wher... The topic on the subspaces for the polynomially or exponentially bounded weak mild solutions of the following abstract Cauchy problem d^2/(dr^2)u(t,x)=Au(t,x);u(0,x)=x,d/(dt)u(0,x)=0,x∈X is studied, where A is a closed operator on Banach space X. The case that the problem is ill-posed is treated, and two subspaces Y(A, k) and H(A, ω) are introduced. Y(A, k) is the set of all x in X for which the second order abstract differential equation has a weak mild solution v( t, x) such that ess sup{(1+t)^-k|d/(dt)〈v(t,x),x^*〉|:t≥0,x^*∈X^*,|x^*‖≤1}〈+∞. H(A, ω) is the set of all x in X for which the second order abstract differential equation has a weak mild solution v(t,x)such that ess sup{e^-ωl|d/(dt)〈v(t,x),x^*)|:t≥0,x^*∈X^*,‖x^*‖≤1}〈+∞. The following conclusions are proved that Y(A, k) and H(A, ω) are Banach spaces, and both are continuously embedded in X; the restriction operator A | Y(A,k) generates a once-integrated cosine operator family { C(t) }t≥0 such that limh→0+^-1/h‖C(t+h)-C(t)‖Y(A,k)≤M(1+t)^k,arbitary t≥0; the restriction operator A |H(A,ω) generates a once- integrated cosine operator family {C(t)}t≥0 such that limh→0+^-1/h‖C(t+h)-C(t)‖H(A,ω)≤≤Me^ωt,arbitary t≥0. 展开更多
关键词 second order abstract differential equation polynomially bounded solution cosine operator function
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From Concrete Object "Tress" of English Poems to Abstract Image in Chinese Counterparts
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作者 刘桂兰 《Sino-US English Teaching》 2007年第1期62-65,共4页
Image is an important and creative way to express poets" feelings in both Chinese and English poetry. There are concrete representations and abstract concept in image. They are two key notions in Poetics and Aestheti... Image is an important and creative way to express poets" feelings in both Chinese and English poetry. There are concrete representations and abstract concept in image. They are two key notions in Poetics and Aesthetics. This paper is to show the different versions of "tress" in poems and to explore the exact nature of concepts of sensitive affection in English and Chinese, so as to appreciate the artistic beauty of images. 展开更多
关键词 POETRY image concrete object abstract concept IMPLICATION
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Theoretical Study on Gas Phase Reactions of OH Hydrogen-Abstraction from Formyl Fluoride with Different Catalysts 被引量:1
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作者 王定美 隆正文 +2 位作者 谭兴凤 龙波 张为俊 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 2016年第3期325-334,I0001,共11页
The mechanisms and kinetics of the gas phase reactions that the hydrogen atom in formyl fluoride (FCHO) abstracted by OH in the presence of water, formic acid (FA), or sulfuric acid (SA) are theoretically invest... The mechanisms and kinetics of the gas phase reactions that the hydrogen atom in formyl fluoride (FCHO) abstracted by OH in the presence of water, formic acid (FA), or sulfuric acid (SA) are theoretically investigated at the CCSD(T)/6-311++G(3df, 3pd)//MO6-2X/6- 311++G(3df, 3pd) level of theory. The calculated results show that the barriers of the transition states involving catalysts are lowered to -2.89, -6.25, and -7.76 kcal/mol from 3.64 kcal/mol with respect to the separate reactants, respectively, which reflects that those catalysts play an important role in reducing the barrier of the hydrogen abstraction reaction of FCHO with OH. Additionally, using conventional transition state theory with Eckart tun- neling correction, the kinetic data demonstrate that the entrance channel X…FCHO+OH (X=H2O, FA, or SA) is significantly more favorable than the pathway X…OH+FCHO. More- over, the rate constants of the reactions of FCHO with OH radical with H2O, FA, or SA introduced are computed to be smaller than that of the naked OH+FCHO reaction because the concentration of the formed X…FCHO or X…OH complex is quite low in the atmosphere. 展开更多
关键词 Formyl fluoride Hydrogen abstraction Reaction mechanisms Rate constants
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Java中抽象类(abstract class)和接口(interface)的使用
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作者 吴小青 《福建电脑》 2007年第1期77-78,共2页
abstract class和interface是Java语言中对于抽象类定义的两种机制,它们之间在对于抽象类定义的支持方面具有很大的相似性,实际上,两者之间还是有区别的,对于它们的选择可以反映出对于问题领域本质的理解、对于设计意图的理解是否正确... abstract class和interface是Java语言中对于抽象类定义的两种机制,它们之间在对于抽象类定义的支持方面具有很大的相似性,实际上,两者之间还是有区别的,对于它们的选择可以反映出对于问题领域本质的理解、对于设计意图的理解是否正确、合理。 展开更多
关键词 抽象类(abstract class) 接口(interface) 面向对象
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