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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 Effect of Na_(2)O/B_(2)O_(3)Composition Ratio on the Structure and Properties of Cu^(+)Doped Luminescent Glass
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作者 LI Bohan FENG Jinyang +3 位作者 FENG Xiaoping ZHAO Xiujian WU Donghua MA Xiao 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS CSCD 2024年第6期1379-1390,共12页
Cu^(+)-doped alkali borosilicate glasses with different Na_(2)O contents were prepared by the melting method,and the effects of different R values(R=Na_(2)O/B_(2)O_(3))on the structure,ion presence state and luminesce... Cu^(+)-doped alkali borosilicate glasses with different Na_(2)O contents were prepared by the melting method,and the effects of different R values(R=Na_(2)O/B_(2)O_(3))on the structure,ion presence state and luminescence properties of Cu^(+)-doped alkali borosilicate glasses were investigated.The analysis by FT-IR and Raman spectroscopy shows that,with the increase of R value of the glass,the[BO_(3)]in the structure of Cu^(+)-doped alkali borosilicate glass transforms into[BO_(4)]and the number of non-bridging oxygen in the glass network appears to be slightly increased.The absorption spectra and EPR analysis reveal that the Cu^(+)content in the glass gradually decreases and the Cu^(2+)content gradually increases as the R value of the glass increases.XPS and PL tests further indicate that the transformation of the octahedral coordination structure of Cu^(+)to the octahedral coordination structure of Cu^(2+)and the cubic coordination structure of Cu^(+)occurs in the glass as the R value of the glass increases.This transformation can effectively reduce the concentration quenching phenomenon of Cu^(+)and improve the fluorescence luminescence intensity of the glass samples.Meanwhile,the samples were found to have luminescence tunability as well as good thermal stability. 展开更多
关键词 R value glass structure Cu ion valence LUMINESCENCE
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Effect of Valence Electron Structure on Temper Process and Hardness of the Supersaturated Carburized Layer 被引量:3
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作者 石巨岩 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2010年第1期127-134,共8页
By measuring the hardness of carburized layer of a new type supersaturated carburizing steel (35Cr3SiMnMoV) at different temper temperature for 2 h, the relationship curve between the carburized layer hardness and t... By measuring the hardness of carburized layer of a new type supersaturated carburizing steel (35Cr3SiMnMoV) at different temper temperature for 2 h, the relationship curve between the carburized layer hardness and the temper temperature is established. The result indicates that the hardness goes down firstly, then up and down, just like a wave consistent with the temperature increase. A secondary hardening peak appears at 570 ℃ or so. Based on Empirical Election Theory (EET) of Solids and Molecules, the valence electron structures (VESs) containing α-Fe-C, α-Fe-C-Me segregation structure units and carbide are calculated. The laws of temper process and hardness change with the temper temperature are explained, and the fact that reconstruction of θ-Fe3C is prior to that of special carbide at high tempering is analyzed with the phase structure formation factor, S, being taken into consideration. Therefore, the laws of temper process and hardness change of supersaturated carburized layer at different temper temperature can be traced back to valence electron structure (VES) level of alloy phase. 展开更多
关键词 supersaturated carburizing steel temper process valence electron structure HARDNESS
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Valence bond structure of Ta-W alloys 被引量:3
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作者 Xiaobo LI Youqing XIE 《Acta Metallurgica Sinica(English Letters)》 SCIE EI CAS CSCD 2009年第4期275-283,共9页
The valence bond structure of substitutional BCC based Ta-W alloys is studied using characteristic crystal (CC) theory. This theory is based on cluster statistics of random alloys. By studying the correlativity betw... The valence bond structure of substitutional BCC based Ta-W alloys is studied using characteristic crystal (CC) theory. This theory is based on cluster statistics of random alloys. By studying the correlativity between energy and volume of the CC in Ta- W alloys, the valence bond structure of CC is determined by the energy and shape method. Then, following additive law of CC, the valence bond structure of Ta-W alloys is calculated. It is found that the outer shell valence electronic distribution of Ta-W Mloys shows a continuous change in the whole composition range. The covalent electrons ec (dc, sc, and pc) increase, whereas near free electrons ef decrease with increasing W concentration. The bond length and single-bond radius decrease, whereas bond energy and bond valence increase with increasing W concentration. The mechanism of solid solution strengthening of Ta-W alloys is analyzed based on their valence bond structure. 展开更多
关键词 valence bond structure Ta-W alloys
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A STUDY OF TEMPERATURE-DEPENDENT VALENCE BOND STRUCTURE OF TITANIUM 被引量:2
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作者 X.B. Li Y.Q. Xie Y.Z. Nie H.J. Peng H.J. Tao F.X. Yu 《Acta Metallurgica Sinica(English Letters)》 SCIE EI CAS CSCD 2007年第1期27-34,共8页
On the basis of energy and shape method for the determination of the valence bond ( VB ) structures of crystal, the valence bond structure of titanium is redetermined at room temperature and calculated in the whole ... On the basis of energy and shape method for the determination of the valence bond ( VB ) structures of crystal, the valence bond structure of titanium is redetermined at room temperature and calculated in the whole temperature range of 0-1943K. The outer shell electronic distribution of Ti is ec^29907. (sc^0.4980 + dc^2.4927) ef^1.0098 in crystal. The temperature dependences of the VB structures of hcp and bcc phases are the same. The VB structures of hcp and bcc phases monotonically increase or decrease with the increase in temperature, but show discontinuous changes at the phase-transformation temperature 1155K. 展开更多
关键词 valence bond structure TEMPERATURE TITANIUM
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Analysis of Transition Mechanism of Cubic Boron Nitride Single Crystals under High Pressure-High Temperature with Valence Electron Structure Calculation 被引量:2
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作者 Mei-Zhe Lv Bin Xu +2 位作者 Li-Chao Cai Feng Jia Xing-Dong Yuan 《Chinese Physics Letters》 SCIE CAS CSCD 2019年第1期10-13,共4页
The possibilities of hexagonal boron nitride(hBN) and lithium boron nitride(Li_3BN_2) transition into cubic boron nitride(cBN) under synthetic pressure 5.0 GPa and synthetic temperature 1700 K are analyzed with the us... The possibilities of hexagonal boron nitride(hBN) and lithium boron nitride(Li_3BN_2) transition into cubic boron nitride(cBN) under synthetic pressure 5.0 GPa and synthetic temperature 1700 K are analyzed with the use of the empirical electron theory of solids and molecules. The relative differences in electron density are calculated for dozens of bi-phase interfaces hBN/cBN, Li_3BN_2/cBN. These relative differences of hBN/cBN are in good agreement with the first order of approximation(<10%), while those of Li_3BN_2/cBN are much greater than 10%.This analysis suggests that Li_3BN_2 is impossible to be intermediate phase but is a catalyst and cBN should be directly transformed by hBN. 展开更多
关键词 Transition Mechanism CUBIC BORON valence Electron structure Calculation
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Hydrothermal Synthesis and Structure of [CH3NH3]2[(VⅣO)2(VⅤO4)2]:A New Layered Mixed-valence Vanadium Oxide Incorporated with Organic Cations 被引量:1
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作者 ZHANG Hong LI Yang-guang +7 位作者 LAN Yang WANG Xiu-li Duan Li-ying WANG En-bo HU Chang-wen YAO Yuan-gen CHEN Jiu-tong QIN Ye-yan 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 2002年第3期252-254,共3页
A new layered mixed valence vanadium oxide, [CH 3NH 3] 2[(V ⅣO) 2(V ⅤO 4) 2], which contains interlamellar organic cations was prepared under hydrothermal conditions and its single crystal structure was determined. ... A new layered mixed valence vanadium oxide, [CH 3NH 3] 2[(V ⅣO) 2(V ⅤO 4) 2], which contains interlamellar organic cations was prepared under hydrothermal conditions and its single crystal structure was determined. It crystallizes in a triclinic system with space group P 1, a =0 625 59(8) nm, b =0 639 84(9) nm, c =0 747 19(10) nm, α =78 718(2)°, β =80 099(2)°, γ =77 100(2). The compound contains mixed valence V 4+ /V 5+ vanadium oxide layers constructed from VO 4 tetrahedra, pairs of edge sharing VO 5 square pyramid and methylamine with protonated organic amines occupying the interlayer space. 展开更多
关键词 Hydrothermal synthesis LAYER Vanadium oxide Mixed valence structure
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Hydrothermal Synthesis, Crystal Structure and Magnetic Property of a Novel Mixed Valence Decatungstate: [Cu(2,2′-bipy)_2]_2Na_2W_6~VW4^(VI)O_(30)·2H_2O 被引量:1
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作者 李涛海 吕健 +1 位作者 高水英 曹荣 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 北大核心 2008年第1期57-62,共6页
A novel Cu(II)-2,2'-bipy-supported (bipy = bipyridine) mixed valence decatungstate, [Cu(2,2'-bipy)2]2Na2W6^VW4^VIO30·2H2O 1, has been synthesized and structurally characterized by X-ray analysis. The crys... A novel Cu(II)-2,2'-bipy-supported (bipy = bipyridine) mixed valence decatungstate, [Cu(2,2'-bipy)2]2Na2W6^VW4^VIO30·2H2O 1, has been synthesized and structurally characterized by X-ray analysis. The crystal of 1 is of triclinic, space group P1^- with a= 10.9393(10), b = 12.0492(2), c = 12.3783(2)A, a = 80.631(10), β= 70.226(10), γ= 72.329(9)^o, V = 1459.64(4)A^3, Z = 1, Dc = 3.582 g/cm^3, F(000) = 1404, R = 0.0553 and wR = 0.1242 for 4607 observed reflections (I 〉 2σ(I)). The EPR spectrum of 1 indicates that its unpaired electrons are placed in the dx2-y2 orbital of the ground state of Cun. Furthermore, compound 1 shows an antiferromagnetic interaction. 展开更多
关键词 crystal structure DECATUNGSTATE mixed valence magnetic property
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A Valence Electron Structure Criterion of Ionic Conductivity of Sr- and Mg-doped LaGaO_3 Ceramics 被引量:1
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作者 Min SHI Ning LIU +3 位作者 Yudong XU Can WANG Yupeng YUAN P.Majewski 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 2006年第2期215-219,共5页
The valence electron structures of Sr- and Mg-doped LaGaO3 ceramics with different compositions were calculated by Empirical Electron Theory of Solids and Molecules (EET). A criterion for the ionic conductivity was ... The valence electron structures of Sr- and Mg-doped LaGaO3 ceramics with different compositions were calculated by Empirical Electron Theory of Solids and Molecules (EET). A criterion for the ionic conductivity was proposed, i.e. the 1/(nAnB) increases with increasing the ionic conductivity when x or y〈20% (in molar fraction). 展开更多
关键词 Empirical electron theory of solids and molecules (EET) valence electron structure LaGaO3 ceramics Ionic conductivity
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Effect of the Structure and Valence State on the Properties of VO_2 Thin Films 被引量:1
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作者 LUYong LINLi-bin 《Semiconductor Photonics and Technology》 CAS 2001年第2期98-103,共6页
VO 2 thin films with good switching properties were prepared by controlling the annealing time and the annealing temperature in a vacuum system. The structural, optical and electrical properties of the samples were ch... VO 2 thin films with good switching properties were prepared by controlling the annealing time and the annealing temperature in a vacuum system. The structural, optical and electrical properties of the samples were characterized by using XRD、XPS、UV-VIS and electrical measurements. The switching parameters of VO 2 thin film were investigated too. The results indicate that before and after phase transition the resistance of VO 2 thin films changes about three orders of magnitude, the variation of film transmittance of 40 % has been carried out with the absorptivity switching velocity of about 0.260 7 /min at 900 nm . The structural property of samples has been improved but the phase-transition properties have been decreased by increasing the annealing time and annealing temperature. The valence of V ions and the structure of samples have great effect on phase transition properties of VO 2 thin films. Discussion on the effects of annealing time and annealing temperature on the phase-transition temperature and hysteresis width shows that the best reasonable annealing time and annealing temperature can be achieved. 展开更多
关键词 VO 2 thin film Phase transition Film structure valence state
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Synthesis and Crystul Structure of A New Mixed-Valence Complex of Copper (Ⅰ, Ⅱ) α-Methacrylate with Triphenylphosphine and Methanol 被引量:1
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作者 Yao Yu WANG Qian SHI +2 位作者 Qi Zhen SHI Yi Ci GAO Zhong Yuan ZHOU (Department of Chemistry, Northwest University Xian 710069)(Department of Chemistry, Lanzhou University, Lanzhou 730000)(Chengdu Institute of Organic Chemistry, Chendou 610041) 《Chinese Chemical Letters》 SCIE CAS CSCD 1998年第11期0-0,0-0,共4页
Copper (Ⅱ) α-methacrylate reacts with triphenylphosphine to form whxed-valence copper (Ⅰ,Ⅱ) complex Cu4(CH2=C(CH3)COO)6(PPh3)4(CH3OH)2 in methanol solution. The crystal and molecular structure of the complex has ... Copper (Ⅱ) α-methacrylate reacts with triphenylphosphine to form whxed-valence copper (Ⅰ,Ⅱ) complex Cu4(CH2=C(CH3)COO)6(PPh3)4(CH3OH)2 in methanol solution. The crystal and molecular structure of the complex has been detendned by single crystal X-ray structural analysis. This material forms pale green crystals with triclinic symmetry, space group Pi, a=1 .3567(2) nm, b=1.3946 (3) nm, c=1.4569 (3) nm, α=66.069 (14)0, β=84.234 (14)0 γ=69.975 (13)0,R=0.0536. 展开更多
关键词 mixed-valence complex SYNTHESIS crystal structure
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Analysis of Valence Electron Structure in Compound Layer of Steel 42CrMo Plasma Nitrided with Rare Earth Addition 被引量:1
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作者 LIUZhan-hong YANMu-fu DAIYa-nan WUKun 《材料热处理学报》 EI CAS CSCD 北大核心 2004年第5期322-324,共3页
The valence electron structure (VES) in compound layer of steel plasma-nitrided at 560°C with rare earth (RE) addition was calculated based on the empirical electron theory (EET) of solids and molecules and BLD m... The valence electron structure (VES) in compound layer of steel plasma-nitrided at 560°C with rare earth (RE) addition was calculated based on the empirical electron theory (EET) of solids and molecules and BLD method. The results show that the presence of RE atoms diffused into surface layer leads to an increase of phase structure factor, which explains the catalyzing and micro-alloying effects of RE. 展开更多
关键词 42CRMO钢 等离子渗氮 稀土 价电子结构
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Analysis of Valence Electron Structure of RE in Solid Solution in Medium and Low Carbon Steel
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作者 朱莹光 刘艳 +1 位作者 刘志林 刘伟东 《Journal of Rare Earths》 SCIE EI CAS CSCD 2004年第2期282-287,共6页
According to EET theory, the valence electron structures of RE in the solid solution of austenite, pearlite and martensite were calculated. The influence of RE in solid solution on phase transformation of pearlite and... According to EET theory, the valence electron structures of RE in the solid solution of austenite, pearlite and martensite were calculated. The influence of RE in solid solution on phase transformation of pearlite and recrystallization of martensite was explained by the valence electron structure data of phases. Calculating results indicate that C element is favorite to enhance the number of RE in the solid solution. RE in the solute solution shortens the incubation period of proeutectoid ferrite, increases its quantity and carbon content, decreases the quantity of pearlite and thickness of its lamellas and lamellar spacing, then the strength and hardness of pearlite are improved and granular pearlite can be obtained. RE dissolved in martensite intensifies martensite, enhances tempering stability of martensite, increases its recrystallization temperature and prolongs the holding time needed during tempering. 展开更多
关键词 metal materials valence electron structure phase transformation RECRYSTALLIZATION rare earths
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Study Segregation of Alloying Elements in Continuous Casting Slab with Valence Electron Structure
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作者 YahLIU ZhilinLIU +1 位作者 ChengweiZHANG YingguangZHU 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 2004年第4期421-425,共5页
By calculating the electron structures of the phases that phosphor, sulfur and alloying elements dissolving inγ-Fe, the reason why alloying elements can bring centerline segregation in continuous casting slab (CCS) w... By calculating the electron structures of the phases that phosphor, sulfur and alloying elements dissolving inγ-Fe, the reason why alloying elements can bring centerline segregation in continuous casting slab (CCS) with nA, the number of electrons on the strongest covalent bonds, and the structure formation factor S were investigated, and an electron structural criterion to control and to eliminate the centerline segregation was advanced. Basing on this, the electron structures of a part of rare earth phosphides and sulfides are calculated, the physical mechanism that rare earth elements can control the segregation of phosphor and sulfur is analyzed, and the criterion is well verified. 展开更多
关键词 valence electron structure Continuous casting slab Centerline segregation Rare-earth elements.
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Synthesis,Crystal Structure and MMCT Property of a New Mixed-valence Cyanide-bridged Binuclear Complex
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作者 孙志豪 王勇 +4 位作者 马骁 王艳龙 胡胜民 盛天录 吴新涛 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2014年第9期1305-1310,共6页
A new mixed-valence cyanide-bridged complex, Br3Fe(p-NC)RuBr(dppm)2 (dppm = bis(diphenylphosphino)methane), was obtained through the reaction between trans-(dppm)2C1- RuCN and FeBr3. Its crystal structure wa... A new mixed-valence cyanide-bridged complex, Br3Fe(p-NC)RuBr(dppm)2 (dppm = bis(diphenylphosphino)methane), was obtained through the reaction between trans-(dppm)2C1- RuCN and FeBr3. Its crystal structure was characterized. Electronic absorption spectra indicate the existence of metal-to-metal charge transfer (MMCT) and this complex is Class II mixed valence complexes according to the classification of Robin and Day. Magnetic analysis shows it is paramagnetic. 展开更多
关键词 CYANIDE-BRIDGED MIXED-valence BINUCLEAR MMCT crystal structure
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Crystal Structure of La_4V_5Si_4O_(22)──A Mixed-Valence Lanthanum Vanadium (Ⅲ/Ⅳ) Oxosilicate
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作者 陈久桐 黄锦顺 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 1995年第4期314-317,共4页
The title compound was prepared by solid state reaction of LaCl_3/V inan evacuated silica tube where the silicon came from the reaction tube. The compoundcrystallizes in monoclinic space group C2/m with cell dimension... The title compound was prepared by solid state reaction of LaCl_3/V inan evacuated silica tube where the silicon came from the reaction tube. The compoundcrystallizes in monoclinic space group C2/m with cell dimensions of a=13. 482 (7), b=5. 604(3), c=11. 091(3) A, β=100. 44(3)°, V=824(1) A3, Mr= 1274. 66 , Dc=5. 14 g/cm3, F(000) = 1150, μ- 13. 20 mm-1 and Z=2; final R=0. 061, Rw=0. 054for 1037 observed reflections (Ⅰ>3σ(Ⅰ) ) . It is isostructural with quasi-ZD Pr_4V_5Si_4O_(22)compound with the Ⅴ-Ⅴ distances across the shared VO6 octahedral edges of 2. 802 Aand vanadium ions show mixed-valence(Ⅲ/Ⅳ) with an average value of+ 3. 2. 展开更多
关键词 lanthanum vanadium oxosilicate crystal structure MIXED-valence
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Influence of Ca addition on valence electron structure of Mg_(17)Al_(12)
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作者 杜温文 孙扬善 +2 位作者 闵学刚 薛烽 武登云 《中国有色金属学会会刊:英文版》 CSCD 2003年第6期1274-1279,共6页
The alloy AZ91 containing calcium was prepared under protection of a mixed gas atmosphere of SF6 (1%, volume fraction) and CO2. The added calcium mainly dissolves into the Mg17Al12 phase in the alloy and increases i... The alloy AZ91 containing calcium was prepared under protection of a mixed gas atmosphere of SF6 (1%, volume fraction) and CO2. The added calcium mainly dissolves into the Mg17Al12 phase in the alloy and increases its melting point and the thermal stability. The empirical electron theory (EET) of solid and molecules was used to calculate the valence electron structures (VES) of Mg17Al12 phase with different amounts of calcium additions. The theoretical calculations indicate that calcium dissolved in Mg17Al12 phase increases the strengths of atomic bonds that control the thermal stability of Mg17Al12 phase, and also makes the distribution of valence electrons on the dominant bond network as well as in the whole unit cell of Mg17Al12 more uniform, which are consistent with the experimental results. 展开更多
关键词 Mg17Al12合金 镁合金 价电子结构
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Valence electron structures and properties of Ni-based corrosion resistant alloy
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作者 杨瑞成 舒俊 +1 位作者 陈奎 王凯旋 《中国有色金属学会会刊:英文版》 CSCD 2007年第A01期84-87,共4页
The corrosion resistance and mechanical properties were tested and compared for the newly synthesized as-cast,as-solution Ni-Cr-Mo-Cu corrosion resistant alloys and 1Cr18Ni9Ti austenitic stainless steel. Their valence... The corrosion resistance and mechanical properties were tested and compared for the newly synthesized as-cast,as-solution Ni-Cr-Mo-Cu corrosion resistant alloys and 1Cr18Ni9Ti austenitic stainless steel. Their valence electron structural units were constructed,and the relative parameters were calculated by means of the Empirical Electron theory of Solids and Molecules(EET). The results show that,during alloy elements Cr,Mo and Cu entering Ni-matrix,the bonding strength nA and bonding energy EA of the strongest bond of the alloy are greatly increased,causing the stronger solid solution strengthening effects(about 30% increase in σb). Also,as reinforcement of the main bond network and the improvement of stability of the alloy system due to the solution of these alloying elements in γ-Ni,the ionization of metal atoms in corrosion solution and the flow of electrons from anode to cathode would all be impeded during electro-chemical corrosion processes,which leads to the excellent corrosion resistant ability of the present Ni-Cr-Mo-Cu alloy(about 2-3 orders of magnitude as high as 1Cr18Ni9Ti austenitic stainless steel) in several highly aggressive solutions. 展开更多
关键词 抗腐蚀合金 原子价 微观结构
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Coherence of the Even-Odd Rule with an Effective-Valence Isoelectronicity Rule for Chemical Structural Formulas: Application to Known and Unknown Single-Covalent-Bonded Compounds 被引量:5
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作者 Geoffroy Auvert 《Open Journal of Physical Chemistry》 2014年第3期126-133,共8页
Ions or molecules are said to be isoelectronic if they are composed of different elements but have the same number of electrons, the same number of covalent bonds and the same structure. This criterion is unfortunatel... Ions or molecules are said to be isoelectronic if they are composed of different elements but have the same number of electrons, the same number of covalent bonds and the same structure. This criterion is unfortunately not sufficient to ensure that a chemical structure is a valid chemical compound. In a previous article, a procedure has been described to draw 2D valid structural formulas: the even-odd rule. This rule has been applied first to single-bonded molecules then to single-charged single-bonded ions. It covers hypovalent, hypervalent or classic Lewis’ octet compounds. The funding principle of the even-odd rule is that each atom of the compound possesses an outer-shell filled only with pairs of electrons. The application of this rule guarantees validity of any single-covalent-bond chemical structure. In the present paper, this even-odd rule and its electron-pair criterion are checked for coherence with an effective-valence isoelectronic rule using numerous known compounds having single-covalent-bond connections. The test addresses Lewis’ octet ions or molecules as well as hypovalent and hypervalent compounds. The article concludes that the even-odd rule and the effective-valence isoelectronicity rule are coherent for known single-covalent-bond chemical compounds. 展开更多
关键词 Isoelectronicity EFFECTIVE valence MOLECULE Ion Even-Odd RULE structural Formula COVALENT Bond
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A Novel Mixed-valence and Capped-keggin Structural Polyoxometal Complex:{[Co(dien)]_4-[(PO_4)Mo_8~Ⅴ(W_(0.56)^(Ⅵ)Mo_(0.44)^(Ⅵ))_4O_(33)(OH)_3 ]}·nH_2O(n≈1) 被引量:2
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作者 胡志彪 陈武华 宓锦校 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2013年第11期1653-1662,共10页
A novel inorganic-organic hybrid compound, {[Co(dien)]4[0aO4)MoV8(wV10.56MoV10.44)4- O33(OH)3]}'nH20 (1, n = 1, dien = diethylenetriamine), has been synthesized hydrothermally and characterized by single-cry... A novel inorganic-organic hybrid compound, {[Co(dien)]4[0aO4)MoV8(wV10.56MoV10.44)4- O33(OH)3]}'nH20 (1, n = 1, dien = diethylenetriamine), has been synthesized hydrothermally and characterized by single-crystal X-ray diffraction. Compound 1 crystallizes in the triclinic system with a = 11.927(2), b = 13.328(3), c = 19.306(4)A, a = 93.76(3), β = 94.14(3), γ = 109.99(3)°, V= 2863.2(12) A3, space group P1 and Z = 2 at 173 K. The final full-matrix least-squares refinement converged to R = 0.049 for 9621 observed reflections with 1 〉 2σ(I) and wR = 0.139 for all data (9871) and S = 1.073. Crystal structure analysis shows that 1 contains a kind of the first reported mixed-valence and molybdenum-tungsten mixed-distributed e-Keggin structural polyanion capped by four Co(dien) fragments with the main group element P occupying the center site. These results were further confirmed by energy-dispersive X-ray spectroscopy (EDS), X-ray powder diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), Raman spectroscopy, Thermogravimetry (TG) and X-ray photoelectron spectroscopy (XPS) analyses. 展开更多
关键词 inorganic-organic hybrid compound e-Keggin-structure hydrothermal synthesis MIXED-valence mixed-distribution
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