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A Corpus-Driven Perspective on the Verb Valency Structure of Chinese EFL Learners:A Case Study of“Suggest”and“Advise”
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作者 ZHENG Yiru ZHANG Le 《Sino-US English Teaching》 2024年第1期14-18,共5页
This paper investigates the verb valency structure of English that is used by English as Foreign Language(EFL)learners from a corpus-driven perspective.Specifically,it focuses on the usage of the verbs“suggest”and“... This paper investigates the verb valency structure of English that is used by English as Foreign Language(EFL)learners from a corpus-driven perspective.Specifically,it focuses on the usage of the verbs“suggest”and“advise”in a selected corpus.By analyzing a sample of written and spoken texts,this study attempts to investigate the similarities and differences in the patterns of verb valency between native English speakers and Chinese EFL learners.The findings of this research can contribute to a better understanding of the challenges faced by Chinese EFL learners in acquiring accurate verb valency structures and provide insights for language teachers in designing effective pedagogical approaches. 展开更多
关键词 valency structure vocabulary teaching synonym distinction CORPUS-DRIVEN
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The Influence of Bond Valence on Bond Covalency in RMn_2O_5 (R=La, Pr, Nd, Sin, Eu) 被引量:1
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作者 Zhi Jian WU Si Yuan ZHANG(Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun 130022) 《Chinese Chemical Letters》 SCIE CAS CSCD 1999年第1期91-94,共4页
The relationship between bond valence and bond covalency in RMn2O5 (R = La, Pr, Nd.Sm, Eu) has been investigated by a semiempirical method. This method is the generalization of thedielectric description theory of Phil... The relationship between bond valence and bond covalency in RMn2O5 (R = La, Pr, Nd.Sm, Eu) has been investigated by a semiempirical method. This method is the generalization of thedielectric description theory of Phillips. Van Vechten, Levine and Tanaka scheme. The resultsindicate that larger valences usually result in higher bond covalencies, in good agreement with thepoint that the excess charge in the bonding region is the origin of formation of bond covalency.Other factors, such as oxidation state of elements, only make a small contribution to bondcovalency. 展开更多
关键词 Bond valence bond covalency semiempirical method RMn_2O_5
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SPECTRAL VARIATION AND CHARACTERISTICS OF LOW VALENCY RARE EARTH IONS IN COMPLEX OXIDESⅢ.EFFECT OF THE CRYSTAL ENVIRONMENT AND CHEMICAL FACTORS ON LUMINESCENCE PROPERTIES OF EUROPIUM (Ⅱ) ION
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作者 孙家跃 石春山 李有谟 《Journal of Rare Earths》 SCIE EI CAS CSCD 1990年第2期110-116,共7页
In this paper,the influence of crystal-field on the Luminescence properties of Eu^(2+) in complex oxides are studied theoretically by using purely electrostatic model,the dependence of the 4f^65d levels on Eu-O bond d... In this paper,the influence of crystal-field on the Luminescence properties of Eu^(2+) in complex oxides are studied theoretically by using purely electrostatic model,the dependence of the 4f^65d levels on Eu-O bond distance is given.Quantum chemistry calculation shows that the splitting extent of 4f^65d energy band in cubic or in octahedral fields will be inversely proportional to R^5,where R is the distance of Eu^(2+) to oxygen ligand.The value of R affects slightly the location of the centre of 4f^65d energy band.According to the exper- imental spectrum data,we have discussed the influence of the host chemical composition,the replaced sites of Eu^(2+) and degree of covalency of Eu-O bond on luminescence properties of Eu^(2+).Some regularity of fluorescence spectrum was observed. In alkali-alkaline earth-phosphates,the splitting extent of 4f^65d band (△E) becomes smaller as the Eu-O bond distance (R) increases.In Na_(3-x)(PO_4)_(1-x)(SO_4)_x and Na_(2-x)CaSi_(1-x)P_xO_4 hosts,d-d emission peak of Eu^(2+) will shift to shorter wavelength with the increase of x's value. The crystal structure data show that Eu^(2+) in K_2Mg_2(SO_4)_3 is affected more strongly by crystal-field and covalancy than in KMgF_3,so K_2Mg_2(SO_4)_3:Eu^(2+) emits blue light (E_(em)~m=400nm) and KMgF_3:Eu^(2+) produces ultraviolet fluorescence. 展开更多
关键词 Eu SPECTRAL VARIATION AND CHARACTERISTICS OF LOW valency RARE EARTH IONS IN COMPLEX OXIDES EFFECT OF THE CRYSTAL ENVIRONMENT AND CHEMICAL FACTORS ON LUMINESCENCE PROPERTIES OF EUROPIUM ION
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Electrochemical Study on the Change in Valency of Niobium Oxide in the MnO-SiO_2-Nb_2O_5 System
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作者 Tan Zanlin Wei Shoukun University of Science and Technology Beijing 《Rare Metals》 SCIE EI CAS CSCD 1990年第1期1-4,共4页
Change in valency of Nb-oxide in MnO-SiO_2-Nb_2O_5 system was studied with the electrochemical method using ZrO_2 as the solid electrolyte.Thermodynamic analysis has shown that the only possible reaction that could ta... Change in valency of Nb-oxide in MnO-SiO_2-Nb_2O_5 system was studied with the electrochemical method using ZrO_2 as the solid electrolyte.Thermodynamic analysis has shown that the only possible reaction that could take place at the working elec- trode is:2(Nb_2O_5)=2(Nb_2O_4)+O_2 with the a_0 values experimentally evaluated,values of a Nb_2O:/a Nb_2O:were calculated and isoactivity-ratio curves drawn in MnO-SiO_2-Nb_2O_5 triangles at 1418 and 1585K.The simultaneous existence of tetra-and penta-valent Nb mineral constituents in industrial Nb-bearing slags was thus verified experimentally. 展开更多
关键词 Electrochemical Study on the Change in valency of Niobium Oxide in the MnO-SiO2-Nb2O5 System SIO MNO
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Valency Increasing in South Ethio-Semitic
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作者 Tsige Yohannes Zeleke 《宏观语言学》 2022年第1期111-131,共21页
The present paper focuses on a descriptive method of valency-increasing devices in five South Ethio-Semitic languages(Amharic,Harari,Kɨstane,Məsqan,and Endəgaɲ).The five languages were selected for two reasons.The fir... The present paper focuses on a descriptive method of valency-increasing devices in five South Ethio-Semitic languages(Amharic,Harari,Kɨstane,Məsqan,and Endəgaɲ).The five languages were selected for two reasons.The first reason is that conducting a valency study on all South Ethio-Semitic languages would have been impossible.With limited resources and time,it will prove difficult to cover all languages.The second reason is that,except for Amharic,these languages are known for being the least studied.Most of them even lack sufficient recording and description.So this research needs to choose the representative language in each branch.As a result,no explicit theoretical framework is followed;data analysis is guided solely by a descriptive perspective.The study’s data was gathered by consulting native speakers via elicitation.Valency has been considered as both a semantic and syntactic notion.As a semantic notion,it is used to refer to the participants in an event;as a syntactic notion,it is used to indicate the number of arguments in a construction.There are different types of transitivity classes of verbs in the South Ethio-Semitic Language,which is spoken in Ethiopia:intransitive,transitive,and ditransitive.Apart from these,there are verbs that can be used both intransitively and transitively.The facts that provide clear evidence for grammatical relations in South Ethio-Semitic languages are crucial to the study of the concept of valency-increasing devices.As is the case in many languages,South Ethio-Semitic languages possess morphosyntactic means through which the valency of verbs can be adjusted.The application of these morphosyntactic processes decreases or increases the valency of verbs.This article looks at valency-increasing devices in Causative and Applicative South Ethio-Semitic languages. 展开更多
关键词 applicative CAUSATIVE INTRANSITIVE SESL TRANSITIVE valency
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LATTICE SUBSTITUTION PROCESS AND VALENCY STABILITY OF EUROPIUM(Ⅱ) IN HOST KMgF_3
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作者 石春山 叶泽人 +1 位作者 姚金玉 孙家跃 《Chinese Science Bulletin》 SCIE EI CAS 1992年第7期571-576,共6页
The electronic transition emission of Eu<sup>2+</sup> is in close relationship with the crystal-field environment and chemical bond property of Eu<sup>2+</sup> in hosts. The stronger the crysta... The electronic transition emission of Eu<sup>2+</sup> is in close relationship with the crystal-field environment and chemical bond property of Eu<sup>2+</sup> in hosts. The stronger the crystal-field intensity is, the larger the splitting of the 5d level is and the more favourable the broad band emission of d-f transition is. The smaller the covalency is, the smaller the 展开更多
关键词 SPECTRA of EUROPIUM (Ⅱ) valency of EUROPIUM ion SUBSTITUTION LATTICE site.
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Influence of bond valence on bond covalency in calcium doped lanthanum chromite
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作者 武志坚 孟庆波 张思远 《Chinese Journal of Chemistry》 SCIE CAS CSCD 1999年第2期108-113,共6页
The influence of bond valence on bond covalence in Lal-xCaxCrO3(x = 0.0, 0.1, 0.2, 0.3) has been studied by using semi empirical method. This method is the extortion of the dialectic description theory proposed by Phi... The influence of bond valence on bond covalence in Lal-xCaxCrO3(x = 0.0, 0.1, 0.2, 0.3) has been studied by using semi empirical method. This method is the extortion of the dialectic description theory proposed by Phillips, Van Vetches, Levine and Tanaka (PVLT). In the calculation of bond valence, two schemes were adopted. The first is the equal-valence scheme, and the second is Bond Valence Sums (BVS) scheme. Bath schemes suggest that for the title compound bond covalence be mainly influenced by bond valence, and insensitive to the Ca doping level. Generally speaking, larger bond valences usually result in higher bond covalence's. 展开更多
关键词 Bond covalence bond valence Lal-xCaxCrO3 semi empirical method
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Morphology and valence state evolution of Cu:Unraveling the impact on nitric oxide electroreduction 被引量:1
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作者 Ting Sun Fengyu Gao +4 位作者 Ya Wang Honghong Yi Qingjun Yu Shunzheng Zhao Xiaolong Tang 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第4期276-286,共11页
Ammonia(NH3)serves as a critical component in the fertilizer industry and fume gas denitrification.However,the conventional NH3production process,namely the Haber-Bosch process,leads to considerable energy consumption... Ammonia(NH3)serves as a critical component in the fertilizer industry and fume gas denitrification.However,the conventional NH3production process,namely the Haber-Bosch process,leads to considerable energy consumption and waste gas emissions.To address this,electrocatalytic nitric oxide reduction reaction(NORR)has emerged as a promising strategy to bridge NH3consumption to NH3production,harnessing renewable electricity for a sustainable future.Copper(Cu)stands out as a prominent electrocatalyst for NO reduction,given its exceptional NH3yield and selectivity.However,a crucial aspect that remains insufficiently explored is the effects of morphology and valence states of Cu on the NORR performance.In this investigation,we synthesized CuO nanowires(CuO-NF)and Cu nanocubes(Cu-NF)as cathodes through an in situ growth method.Remarkably,CuO-NF exhibited an impressive NH3yield of 0.50±0.02 mg cm^(-2)h^(-1)at-0.6 V vs.reversible hydrogen electrode(RHE)with faradaic efficiency of29,68%±1,35%,surpassing that of Cu-NF(0.17±0.01 mg cm^(-2)h^(-1),16.18%±1.40%).Throughout the electroreduction process,secondary cubes were generated on the CuO-NF surface,preserving their nanosheet cluster morphology,sustained by an abundant supply of subsurface oxygen(s-O)even after an extended duration of 10 h,until s-O depletion ensued.Conversely,Cu-NF exhibited inadequate s-O content,leading to rapid crystal collapse within the same timeframe.The distinctive current-potential relationship,akin to a volcano-type curve,was attributed to distinct NO hydrogenation mechanisms.Further Tafel analysis revealed the exchange current density(i0)and standard heterogeneous rate constant(k0)for CuO-NF,yielding 3.44×10^(-6)A cm^(-2)and 3.77×10^(-6)cm^(-2)s^(-1)when NORR was driven by overpotentials.These findings revealed the potential of CuO-NF for NO reduction and provided insights into the intricate interplay between crystal morphology,valence states,and electrochemical performance. 展开更多
关键词 NORR Ammonia Synthesis COPPER MORPHOLOGY Valence States Mechanism
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Valence Bands Convergence in p-Type CoSb_(3) through Electronegative Fluorine Filling
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作者 黄写格 李家良 +5 位作者 马浩钦 李昌隆 刘天乐 段波 翟鹏程 李国栋 《Chinese Physics Letters》 SCIE EI CAS CSCD 2024年第7期87-94,共8页
Band convergence is considered to be a strategy with clear benefits for thermoelectric performance,generally favoring the co-optimization of conductivity and Seebeck coefficients,and the conventional means include ele... Band convergence is considered to be a strategy with clear benefits for thermoelectric performance,generally favoring the co-optimization of conductivity and Seebeck coefficients,and the conventional means include elemental filling to regulate the band.However,the influence of the most electronegative fluorine on the CoSb_(3) band remains unclear.We carry out density-functional-theory calculations and show that the valence band maximum gradually shifts downward with the increase of fluorine filling,lastly the valence band maximum converges to the highly degenerated secondary valence bands in fluorine-filled skutterudites. 展开更多
关键词 VALENCE CONVERGENCE BANDS
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Multiscale confinement nitridation in molybdenum carbide for efficient hydrogen production
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作者 Liming Dai Chenchen Fang +10 位作者 Xiaoyuan Zhang Xuefeng Xu Xuanxuan Chen Xinyue Zong Xueming Hu Wenyao Zhang Liang Xue Pan Xiong Yongsheng Fu Jingwen Sun Junwu Zhu 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第7期61-69,共9页
The molybdenum carbide(Mo_(2)C)has been regarded as one of the most cost-efficient and stable electrocatalyst for the hydrogen evolution reaction(HER)by the virtue of its Pt-like electronic structures.However,the inhe... The molybdenum carbide(Mo_(2)C)has been regarded as one of the most cost-efficient and stable electrocatalyst for the hydrogen evolution reaction(HER)by the virtue of its Pt-like electronic structures.However,the inherent limitation of high density of empty valence band significantly reduces its catalytic reactivity by reason of strong hydrogen desorption resistance.Herein,we propose a multiscale confinement synthesis method to design the nitrogen-rich Mo_(2)C for modulating the band structure via decomposing the pre-coordination bonded polymer in a pressure-tight tube sealing system.Pre-bonded c/N-Mo in the coordination precursor constructs a micro-confinement space,enabling the homogeneous nitrogenization in-situ happened during the formation of Mo_(2)C.Simultaneously,the evolved gases from the precursor decomposition in tube sealing system establish a macro-confinement environment,preventing the lattice N escape and further endowing a continuous nitridation.Combining the multiscale confinement effects,the nitrogen-rich Mo2C displays as high as 25%N-Mo concentration in carbide lattice,leading to a satisfactory band structure.Accordingly,the constructed nitrogen-rich Mo_(2)C reveals an adorable catalytic activity for HER in both alkaline and acid solution.It is anticipated that the multiscale confinement synthesis strategy presents guideline for the rational design of electrocatalysts and beyond. 展开更多
关键词 Molybdenum carbide Hydrogen evolution reaction Multiscale confinement synthesis Valence band modulation Nitrogen doping
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Enhanced anomalous Hall effect in kagome magnet YbMn_(6)Sn_(6)with intermediate-valence ytterbium
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作者 李龙飞 迟晟玮 +3 位作者 马文龙 郭凯臻 徐刚 贾爽 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第5期43-50,共8页
We report on the magnetization and anomalous Hall effect(AHE)in the high-quality single crystals of the kagome magnet YbMn_(6)Sn_(6),where the spins of the Mn atoms in the kagome lattice order ferromagnetically and th... We report on the magnetization and anomalous Hall effect(AHE)in the high-quality single crystals of the kagome magnet YbMn_(6)Sn_(6),where the spins of the Mn atoms in the kagome lattice order ferromagnetically and the intermediate-valence Yb atoms are nonmagnetic.The intrinsic mechanism plays a crucial role in the AHE,leading to an enhanced anomalous Hall conductivity(AHC)compared with the other rare-earth RMn_(6)Sn_(6)compounds.Our band structure calculation reveals a strong hybridization between the 4f electrons of Yb and conduction electrons. 展开更多
关键词 anomalous Hall effect kagome magnet intermediate valence
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Valence electron structures dependences of structural stability and properties of REX_(3)(RE=rare earth;X=In,Tl)and RE(In,Co)3 alloys
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作者 Boyang Li Yongquan Guo +2 位作者 Yi-Chen Feng Xinze Wang Wei Liu 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第11期331-339,共9页
Intermetallic compounds REIn3(RE=rare earth)have attracted much attention due to their unique characteristics:crystal field effect,Kondo effect,superconductivity,heavy fermion,and antiferromagnetism,and their cobalt d... Intermetallic compounds REIn3(RE=rare earth)have attracted much attention due to their unique characteristics:crystal field effect,Kondo effect,superconductivity,heavy fermion,and antiferromagnetism,and their cobalt diluted alloys exhibit the ferromagnetic half-metallic characteristics at room temperature.In this study,an empirical electron theory(EET)is employed to investigate systemically the valence electronic structure,the thermal and magnetic properties of REX_(3) and their cobalt diluted alloys for revealing the mechanism of physical properties.The calculated bond length,melting point,and magnetic moment match the experimental ones very well.The study reveals that structural stability and physical properties of REX_(3) and their cobalt dilute alloys are strongly related to their valence electron structures.It is suggested that the structural stability and cohesive energy depend upon the covalent electron,the melting point is modulated by covalent electron pair,and the magnetic moment is originated from 3d magnetic electron.The ferromagnetic characteristics of Co-diluted REIn3 alloys is originated from the introduction of strong ferromagnetic Co atom,but,a competition is caused between the electron transition from valence electron to magnetic electron on d orbit and its reversal electron transformation with increasing the content of cobalt,which results in the formations of diluted magnetic Gd(In,Co)3 alloy with minor amount of cobalt and strong magnetic Nd(In,Co)3 alloy with doping more Co atoms. 展开更多
关键词 REX_(3) cobalt dilute alloy valence electron structures empirical electron theory MOMENT
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Promoting sustainable consumption and circular economy:the intention of Vietnamese youth consumers to purchase products made from recycled plastics
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作者 Hong Thi Thu Nguyen 《Chinese Journal of Population,Resources and Environment》 2024年第2期194-203,共10页
Recycling is viewed as a key component in a circular economy and serves as an ideal solution for promoting sustainability.During the global plastic crisis,plastic recycling practices have been adopted worldwide,leadin... Recycling is viewed as a key component in a circular economy and serves as an ideal solution for promoting sustainability.During the global plastic crisis,plastic recycling practices have been adopted worldwide,leading to the production of various products made from recycled plastics(PRP).Nevertheless,a gap persists between consumption and demand for such products,which is primarily attributed to a lack of comprehension from the consumer perspective.Given the pivotal role consumers play in the adoption of these products,this study explores consumers’intentions to purchase PRP.This is particularly significant in Vietnam,which is an emerging economy aspiring to achieve the objectives of a circular economy and sustainable development.Utilizing an integrated cognitive-emotional framework comprising the Valence Theory and the Norm Activation Model,data from 564 Vietnamese students were gathered and analyzed using structural equation modeling.The results show that awareness of consequences is a major driver of consumer purchase intentions,followed by perceived ease of application and monetary incentives.The results also indicate that health concerns have the strongest effect on purchase intention and in the negative side,meaning that the health-related risk is the primary concern for consumers during the decision-making process.This research holds substantial value for academics and managers,as it aids in the theoretical exploration and the formulation of strategies to improve consumer acceptance of PRP. 展开更多
关键词 Recycled plastics Purchase intention Sustainable consumption Circular economy Valence theory Norm activation model
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Semantic Foundation and Evolution Mechanism of the“好不X”(haobu X)Structure
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作者 Qian Wang Qinwei Zhou +2 位作者 Di Zhang Jiajia Shi Siqian Cheng 《Journal of Contemporary Educational Research》 2024年第10期1-15,共15页
In Chinese,the“好不X”(haobu X)structure expresses three types of meanings(negation,affirmation,and both affirmation-negation),where X exhibits differences in semantic symmetry.So far,no systematic explanatory theory... In Chinese,the“好不X”(haobu X)structure expresses three types of meanings(negation,affirmation,and both affirmation-negation),where X exhibits differences in semantic symmetry.So far,no systematic explanatory theory has been proposed to account for these differences.Therefore,this paper presents and argues for an explanatory hypothesis that progresses through four stages:“很不X”(henbu X)=>“好不X”(haobu X)(negation)=>[ironic use]“好不X”(haobu X)(affirmation)=>expansion and obstruction of affirmative“好不”(haobu).Specifically,(1)the basis of the negation“好不X”(haobu X)is attributed to“很不X”(henbu X),and the semantic asymmetry of X(excluding negative words)is explained using politeness principles,irony,and the semantic valence of negation results;(2)the ironic use of the negation“好不X”(haobu X)gives rise to the affirmation“好不X”(haobu X);(3)the grammaticalization and expansion of the positive meaning of“好不”(haobu)extend to X,which cannot appear in the negative meaning“好不__”structure(including words with opposite meanings and high polarity positive words).This explains the semantic symmetry of X in the positive meaning“好不X”(haobu X)structure;(4)when the affirmation“好不”(haobu)expands to the negation“好不X”(haobu X),it encounters both obstacles(X includes neutral and some positive words)and compatibility(X is some other positive words),thus explaining the semantic asymmetry of X in the affirmation-negation“好不X”(haobu X)(i.e.,X is positive words). 展开更多
关键词 haobu X Semantic(a)symmetry of X Politeness principle IRONY Semantic valence Adverb“hao”
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Equalized Electronegativity Based on the Valence Electrons and Its Application 被引量:2
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作者 武亚新 曹晨忠 袁华 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 2011年第1期31-39,I0003,共10页
We take the contribution of all valence electrons into consideration and propose a new valence electrons equilibration method to calculate the equalized electronegativity including molecular electronegativity, group e... We take the contribution of all valence electrons into consideration and propose a new valence electrons equilibration method to calculate the equalized electronegativity including molecular electronegativity, group electronegativity, and atomic charge. The ionization potential of alkanes and mono-substituted alkanes, the chemical shift of 1H NMR, and the gas phase proton affinity of aliphatic amines, alcohols, and ethers were estimated. All the expressions have good correlations. Moreover, the Sanderson method and Bratsch method were modified on the basis of the valence electrons equilibration theory. The modified Sanderson method and modified Bratsch method are more effective than their original methods to estimate these properties. 展开更多
关键词 Electronegativity equalization Valence electrons equilibration method Molecular electronegativity Group electronegativity Atomic charge
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STUDY ON DEGRADATION OF LDPE CATALYZED BY MULTI-VALENCE METALLIC ORGANIC COMPOUNDS AT COMPOST TEMPERATURE
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作者 于九皋 陈崧哲 《Transactions of Tianjin University》 EI CAS 2001年第4期290-293,共4页
The catalytic effects of the organic compounds of iron,tin and manganese on the degradation of low density polyethylene (LDPE) at compost temperature are discussed.A series of samples were aged in a simulating compost... The catalytic effects of the organic compounds of iron,tin and manganese on the degradation of low density polyethylene (LDPE) at compost temperature are discussed.A series of samples were aged in a simulating compost environment.The mechanical properties,viscosity average molecular weight (M η) of PE and hydroperoxide (POOH) concentration in the samples were measured.FT IR and DSC were also applied to characterize some samples.It was shown that the above mentioned metallic organic compounds can catalyze the degradation of LDPE efficiently.After 2 months aging,all samples with catalysts became fragile and the M η of the material decreased dramatically.Furthermore,the concentration of carbonyl and the degree of crystallinity of the material increased with the aging time. 展开更多
关键词 polyethylene multi valence metallic organic compound COMPOST DEGRADATION HYDROPEROXIDE
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Valence states, impurities and electrocrystallization behaviors during molten salt electrorefining for preparation of high-purity titanium powder from sponge titanium 被引量:11
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作者 翁启刚 李瑞迪 +2 位作者 袁铁锤 李健 贺跃辉 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2014年第2期553-560,共8页
High-purity titanium powder was prepared by molten salt electrorefining from sponge titanium in NaCl-KCl-TiClx salts. The titanium valence, purity and electrocrystallization during electrolysis process were studied. T... High-purity titanium powder was prepared by molten salt electrorefining from sponge titanium in NaCl-KCl-TiClx salts. The titanium valence, purity and electrocrystallization during electrolysis process were studied. The XPS analysis showed that the titanium valences are mainly +4, +3 and +2 at the earlier, medium and later stages of electrolysis, respectively. During the electrolysis process, the contents of impurities Si, Cr, Mn, Al vary little, and the contents of impurities Fe, Cu, Ni decrease markedly, while the contents of impurities O, N, H increase obviously. The residual impurities are usually distributed in small tunnel of dendritic crystals. Enhancing the electrolysis temperature and prolonging the electrolysis time can increase the titanium particle size. The TEM analysis showed that the electrodeposited titanium is not a single crystal, but contains many nanostructured grains and subgrains, with grain size of 100-500 nm. The electrolysis mechanisms were also discussed. 展开更多
关键词 molten salt electrolysis high-purity titanium powder VALENCE ELECTROCRYSTALLIZATION
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Basic Concepts of Graph Theory as the Instruments of Mathematical Formalization of Woven Structures
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作者 Otabek Kasimov 《World Journal of Engineering and Technology》 2015年第3期344-347,共4页
The paper presents the prerequisites of involving of topological elements and graph theory as an instrument of mathematical formalization of woven structures and technology of textile fabrics. Present research is base... The paper presents the prerequisites of involving of topological elements and graph theory as an instrument of mathematical formalization of woven structures and technology of textile fabrics. Present research is based on analysis and comparison of the main concepts and conditions of textile technology and graph theory. 展开更多
关键词 Textile WEAVING Structure Plain Weave Twill Weave RAPPORT Topology Graph Theory Vertex valency Edge WARP WEFT
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The Verbs of Motion“Ba” (come) and “Hevi” (bring)in Dictionaries of Contemporary Hebrew
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作者 Pnina Trommer Avi Gvura Rama Manor 《Journal of Literature and Art Studies》 2015年第5期355-367,共13页
We focused in this study on two verbs of motion ba (come) and hevi (bring) used in contemporary Hebrew pointing to a number of semantic shifts occurring in each of them and to categorical shifts that occurred in t... We focused in this study on two verbs of motion ba (come) and hevi (bring) used in contemporary Hebrew pointing to a number of semantic shifts occurring in each of them and to categorical shifts that occurred in the verb ha. We conducted a semantic and syntactic analysis of these shifts in which we observed: a change in the syntactic valuation of ba and hevi, the semantic characteristic of the nominal collocations which form their syntactic setting, and the semantic connection between their original and new meanings. The article starts out with a presentation of the original meanings of the two verbs as belonging to the family of concrete verbs of motion. It then presents the semantic shifts each undergoing from designating motion to designating giving, existing, and modality (capability, intent and aspect) and concludes with the categorical shift of the verb ba to impersonal (ロ"λ∏) and to discourse marker. It is noteworthy that in each of the shifts observed we noticed relation between the meaning stemming from the shift and the original meaning of ba and hevi as verbs of motion. We were able to prove that the original meaning is still echoed both in the semantic and category categorical shifts. 展开更多
关键词 semantic shift categorical shift motion verb syntactic valency location of goal
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Mathematical Approaches to the Structural Analysis and Formalization of Woven Fabrics
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作者 Askarali Daminov Otabek Kasimov 《World Journal of Engineering and Technology》 2016年第3期263-269,共7页
The present paper shows the mathematical approach of formalization of textile fabrics, based on concepts and elements of graph theory and the structural analysis of woven structures and possibility of numerical evalua... The present paper shows the mathematical approach of formalization of textile fabrics, based on concepts and elements of graph theory and the structural analysis of woven structures and possibility of numerical evaluation of interlacing factor of warp and weft threads in woven structures through the weight of a structural graph vertex. Research observes quantitative aspect of structural evaluation of threads topology in fabric focusing in graph theory, in order to present an application productivity of this theory to solve the technological tasks. 展开更多
关键词 Textile WEAVING Structure Plain Weave Twill Weave RAPPORT WARP Weft Topology Graph Theory Vertex valency Edge
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