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基于Profibus-DP总线的Quantum与S7-300通信研究 被引量:1
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作者 沈克宇 罗旭 +1 位作者 李志俊 王岭 《装备制造技术》 2008年第5期44-45,共2页
研究了基于Profibu-DP总线的异种PLC之间的通信方法与实现。介绍了系统的应用环境(某港口散粮监控系统),从PLC通信技术入手,对Quantum与S7-300的通信方法进行了探讨,以及主站和从站的硬件组成,最终通过GSD文件完成了监控系统主站与电子... 研究了基于Profibu-DP总线的异种PLC之间的通信方法与实现。介绍了系统的应用环境(某港口散粮监控系统),从PLC通信技术入手,对Quantum与S7-300的通信方法进行了探讨,以及主站和从站的硬件组成,最终通过GSD文件完成了监控系统主站与电子秤从站的通信连接,从而使散粮监控系统更加完善,自动化程度更高。 展开更多
关键词 PLC quantum S7-300 通信
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TSQ Quantum液相色谱-串联质谱法测定十种全氟烷基化合物 被引量:1
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作者 刘飞 王勇为 刘婷 《环境化学》 CAS CSCD 北大核心 2011年第8期1530-1531,共2页
全氟烷基化合物(Perfluorinated alkyl substances,PFAS)是一类普遍存在的环境污染物,自1951年由3M公司研制成功以来,已有50多年的生产和使用历史,以其良好的表面活性被广泛应用于纺织、造纸、包装、皮革、装潢、表面活性剂等多个领... 全氟烷基化合物(Perfluorinated alkyl substances,PFAS)是一类普遍存在的环境污染物,自1951年由3M公司研制成功以来,已有50多年的生产和使用历史,以其良好的表面活性被广泛应用于纺织、造纸、包装、皮革、装潢、表面活性剂等多个领域.由于PFAS具有难降解性、生物蓄积性、沿食物链在生物体内富集以及潜在的生物毒性, 展开更多
关键词 液相色谱-串联质谱法 烷基化合物 quantum 环境检测 全氟 表面活性剂 专题 科技
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Synthesis, Structure and Quantum Mechanical Calculations of Methyl 2-(5-((Quinolin-8-yloxy)-methyl)-1,3,4-oxadiazol-2-ylthio)-acetate
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作者 AAMER SAEED FOUZIA PERVEEN +2 位作者 NAEEM ABBAS SIDRA JAMAL ULRICH FL?RKE 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2015年第6期858-870,共13页
The title compound was synthesized by the base catalyzed reaction of 5-((quinolin- 8-yloxy)methyl)-1,3,4-oxadiazole-2(3H)-thione with methyl chloroacetate. The structure was supported by the spectroscopic data a... The title compound was synthesized by the base catalyzed reaction of 5-((quinolin- 8-yloxy)methyl)-1,3,4-oxadiazole-2(3H)-thione with methyl chloroacetate. The structure was supported by the spectroscopic data and unambiguously confirmed by single-crystal X-ray diffraction studies. It crystallizes from a methanol solution in the triclinic space group Pi with unit cell dimensions a = 7.4509(9), b = 10.2389(12), c = 12.2299(15)A, a = 74.771(2), β = 77.956(2), 7 = 69.263(2)°, V = 834.98(17) A3 and Z = 2. In order to gain some valuable insights into the molecular structure, the quantum mechanical calculations were performed using both HF and time-dependent density functional theory at the B3LYP/6-31G(d,p) level. The molecular geometry from X-ray determination of the title compound in the ground state has been compared using the Hartree-Fock (HF) and density functional theory (DFT) with the 6-31G(d) basis set. The calculated results show that the DFT and HF can well reproduce the structure of the title compound. The energetic behavior of the title compound was examined using the B3LYP method with the 6-31G(d) basis set. The harmonic vibrational frequencies calculated have been compared with the experimental FTIR and FT-Raman spectra. The restricted Hartree-Fock and density functional theory-based nuclear magnetic resonance (NMR) calculation procedure was also performed, and it was used for assigning the 13C and 1H NMR chemical shifts of the title compound. Moreover, molecular electrostatic potential and thermodynamic parameters of the title compound were investigated by theoretical calculations. 展开更多
关键词 methyl 2-(5-((quinolin-8-yloxy)methyl)-1 3 4-oxadiazol-2-ylthio)acetate CRYSTALSTRUCTURE CONFORMER quantum chemical calculations vibrational studies
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Regulation of photophysical and electronic properties of I-III-VI quantum dots for light-emitting diodes
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作者 Xiaofei Dong Xianggao Li +3 位作者 Shougen Yin Zheng Li Longwu Li Jingling Li 《Science China Materials》 SCIE EI CAS CSCD 2024年第9期2737-2748,共12页
Quantum dot light-emitting diodes(QLEDs)have become an important research direction in the pursuit of next-generation display technology owing to their favorable attributes,including high energy efficiency,wide color ... Quantum dot light-emitting diodes(QLEDs)have become an important research direction in the pursuit of next-generation display technology owing to their favorable attributes,including high energy efficiency,wide color gamut,and low cost.Breakthroughs in the luminous efficiency and operating life of QLEDs have been achieved by enhancing the photoluminescence efficiency of the quantum dots(QDs)and optimizing the device structure.However,the current mainstream QDs contain heavy metal elements such as lead and cadmium,which restrict the development and application of QD displays.Exploring new types of environmentally friendly QDs is crucial.I-III-VI semiconductor QDs have been developed as luminescent materials for constructing high color rendering index QLEDs,owing to the outstanding photophysical properties of these QDs,such as composition-dependent tunable bandgap,large Stokes shift,and highefficiency luminescence.Currently,the microstructures of heterojunctions,especially the surface states and interface states,affect the recombination and transport of carriers in electroluminescent(EL)devices with multilayer thin film structures,which in turn influence the luminous efficiency and stability of the device.This review focuses on the synthesis strategies of I-III-VI multi-component QDs and provides an in-depth understanding of the luminescence mechanism and the regulation of photophysical and electronic properties.Furthermore,the application of I-III-VI QDs in multi-color and white EL QLEDs is discussed and the challenges and outlook are addressed. 展开更多
关键词 --quantum dots synthesis method defect states luminescence mechanism light-emitting diodes
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产超广谱β-内酰胺酶肺炎克雷伯菌和大肠埃希菌的TEM基因测序
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作者 谢国强 盛裕芬 +1 位作者 王春新 刘峰 《现代实用医学》 2001年第11期542-543,共2页
目的 对产超广谱 β-内酰胺酶 (ESBLs)的肺炎克雷伯菌 (Kpn)和大肠埃希菌 (Eco)的TEM基因进行序列测定。 方法 分A、B、C 3段扩增TEM基因 ,并对A、B、C 3段扩增产物进行四色荧光标记全自动测序。 结果 来源于呼吸道 (痰 )的 3株Kp... 目的 对产超广谱 β-内酰胺酶 (ESBLs)的肺炎克雷伯菌 (Kpn)和大肠埃希菌 (Eco)的TEM基因进行序列测定。 方法 分A、B、C 3段扩增TEM基因 ,并对A、B、C 3段扩增产物进行四色荧光标记全自动测序。 结果 来源于呼吸道 (痰 )的 3株Kpn和分别来源于呼吸道 (痰 )、泌尿道 (尿 )、胆道 (胆汁 )和分泌物中的 1 1株Eco测得的TEM序列完全一致。 结论 被检测的来源于不同病灶、不同菌种(Kpn与Eco)的超广谱β -内酰胺酶 (ESBLs)含同种TEM的质粒。 展开更多
关键词 细菌抗药性 TEM基因 超广谱β-丙酰胺酶 Kpn eco 基因测序
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Latest advances in high-performance light sources and optical amplifiers on silicon 被引量:5
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作者 Songtao Liu Akhilesh Khope 《Journal of Semiconductors》 EI CAS CSCD 2021年第4期81-89,共9页
Efficient light generation and amplification has long been missing on the silicon platform due to its well-known indirect bandgap nature.Driven by the size,weight,power and cost(SWaP-C)requirements,the desire to fully... Efficient light generation and amplification has long been missing on the silicon platform due to its well-known indirect bandgap nature.Driven by the size,weight,power and cost(SWaP-C)requirements,the desire to fully realize integrated silicon electronic and photonic integrated circuits has greatly pushed the effort of realizing high performance on-chip lasers and amplifiers moving forward.Several approaches have been proposed and demonstrated to address this issue.In this paper,a brief overview of recent progress of the high-performance lasers and amplifiers on Si based on different technology is presented.Representative device demonstrations,including ultra-narrow linewidthⅢ-Ⅴ/Si lasers,fully integratedⅢ-Ⅴ/Si/Si3N4 lasers,high-channel count mode locked quantum dot(QD)lasers,and high gain QD amplifiers will be covered. 展开更多
关键词 -Ⅴ/Si photonic integrated circuits semiconductor lasers semiconductor amplifier quantum dots
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Enhanced piezoresistivity in Ni-silicone rubber composites 被引量:1
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作者 常方高 杨枫 +2 位作者 王少祥 张娜 宋桂林 《Chinese Physics B》 SCIE EI CAS CSCD 2009年第2期652-657,共6页
This paper reports that the nickel-silicone rubber composites with enhanced piezoresistivity were synthesized with much reduced nickel concentration. A large piezosensitivity of 0.716/kPa and a gauge factor of 600 hav... This paper reports that the nickel-silicone rubber composites with enhanced piezoresistivity were synthesized with much reduced nickel concentration. A large piezosensitivity of 0.716/kPa and a gauge factor of 600 have been obtained for a composite sample with filler-polymer ratio of 2.7:1 by weight. Measurements of resistance as a function of uniaxial force reveal that the piezoresistance arises predominantly from the internal heterogeneity of the material and the effect of geometrical changes of samples under pressure is negleetably small. The nonlinear current-voltage characteristic of the composite depends strongly on the filler content, the initial compression and the electrical current flowing in the sample. Ohmic behaviour has been observed only in the highly compressed samples. The breakdown strength decreases with increasing filler content of the composite. Both I - V and R - f characteristics indicates that the resistivity of the composites decreases with electrical field, suggesting that the composite may also be used to make voltage sensitive resistors for protecting circuits. All the experimental results favour a quantum tunnelling mechanism of conductivity. It finds that the concept 'negative resistance', often used to describe the phenomena that current decreases with increasing voltage, is not appropriate and should be avoided. 展开更多
关键词 PIEZORESISTIVITY quantum tunnelling I - V characteristics voltage sensitive resistors
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Chemial Bond and Stability of Adsorption of [Au(AsS_3)]^(2-)on the Surface of Kaolinite 被引量:1
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作者 闵新民 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2004年第1期5-8,共4页
Density function theory and discrete variation method (DFT-DVM) were used to study the adsorption of [Au(AsS 3)] 2- on the surface of kaolinite.The correlation among structure,chemical bond and stability was discuss... Density function theory and discrete variation method (DFT-DVM) were used to study the adsorption of [Au(AsS 3)] 2- on the surface of kaolinite.The correlation among structure,chemical bond and stability was discussed.Several models were selected with [Au(AsS 3)] 2- in different directions and sites.The results show that the models with gold on the edge of kaolinite basal layer contain pincerlike bond among gold and several oxygen atoms and form strong Au-O covalent bond,so these models are more stable than those with gold above or under the layer.The models with gold near to [AlO 2(OH) 4] octahedra are more stable than those with gold near to the vacancy without aluminium.These two stable tendencies in kaolinite-[Au(AsS 3)] 2- are stronger than that in kaolinite-Au systems.The interaction between [Au(AsS 3)] 2- and kaolinite is stronger than that between gold and kaolinite,and this interaction is strong enough to form the surface complexes. 展开更多
关键词 kaolinite-[Au(AsS 3)] 2- structure chemical bond STABILITY quantum chemistry calculation
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Fabrication and properties of high performance YBa_2Cu_3O_(7-δ) radio frequency SQUIDs with step-edge Josephson junctions 被引量:1
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作者 刘政豪 魏玉科 +3 位作者 王达 张琛 马平 王越 《Chinese Physics B》 SCIE EI CAS CSCD 2014年第9期419-422,共4页
We describe the fabrication of high performance YBa2Cu3O7-δ (YBCO) radio frequency (RF) superconducting quantum interference devices (SQUIDs), which were prepared on 5 mm×5 mm LaAlO3 (LAO) substrates by ... We describe the fabrication of high performance YBa2Cu3O7-δ (YBCO) radio frequency (RF) superconducting quantum interference devices (SQUIDs), which were prepared on 5 mm×5 mm LaAlO3 (LAO) substrates by employing stepedge junctions (SEJs) and in flip-chip configuration with 12 mm×12 mm resonators. The step in the substrate was produced by Ar ion etching with step angles ranging from 47° to 61°, which is steep enough to ensure the formation of grain boundaries (GBs) at the step edges. The YBCO film was deposited using the pulsed laser deposition (PLD) technique with a film thickness half of the height of the substrate step. The inductance of the SQUID washer was designed to be about 157 pH. Under these circumstances, high performance YBCO RF SQUIDs were successfully fabricated with a typical flux-voltage transfer ratio of 83 mV/φ0, a white flux noise of 29 μφ0/√Hz, and the magnetic field sensitivity as high as 80 fT/√Hz. These devices have been applied in magnetocardiography and geological surveys. 展开更多
关键词 superconducting quantum interference device (SQUID) YBa2Cu3O7-δ (YBCO) step-edge junction radio frequency
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无铅ECO弹性体胶料 被引量:2
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作者 陶华 《世界橡胶工业》 2004年第9期8-16,共9页
该文针对福特公司和大众公司的两个汽车胶管的标准列举了一些实例 ,以证明 TCY硫化体系完全可以在 ECO弹性体中替代铅 /ETU硫化体系。该文例举了大量事实证明了 ECO胶料的耐油及耐燃料性取决于聚合物的结构 。
关键词 ETU 无铅eco弹性体胶料 ECH 聚氯醚弹性体 亚乙基硫脲 三聚氰硫酸 2 4 6-三巯基-1 3 5-三吖嗪 均三巯基三吖嗪 表面处理剂
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3,6-bis(2,2,2-trinitroethylnitramino)-1,2,4,5-tetrazine.Structure and energy abilities as a component of solid composite propellants
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作者 Anatoly G.Korepin Natalia M.Glushakova +6 位作者 David B.Lempert Anatoly I.Kazakov Gennady V.Shilov Denis V.Korchagin Vadim M.Volokhov Elena S.Amosova Sergey M.Aldoshin 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2022年第7期1148-1155,共8页
The work addresses to the study of the molecular and crystal structure and properties of a new energyintensive compound 3,6-bis(2,2,2-trinitroethylnitramino)-1,2,4,5-tetrazine(NBTAT),first obtained by the authors in 2... The work addresses to the study of the molecular and crystal structure and properties of a new energyintensive compound 3,6-bis(2,2,2-trinitroethylnitramino)-1,2,4,5-tetrazine(NBTAT),first obtained by the authors in 2020.NBTAT compound crystallizes in the monoclinic system,space group P2(1)/n,density at room temperature 1.939 g/cm^(3).The energies of crystal packing and pairwise intermolecular interactions in NBTAT and its unnitrated analogue BTAT were calculated,and their comparative analysis was carried out.The enthalpy of formation of NBTAT molecules was calculated by quantum-chemical methods using Gaussian 09,and the enthalpy of formation of NBTAT in the solid phase(618 kJ/mol)was estimated.The energy capabilities of NBTAT as an oxidizer of solid composite propellants are estimated.It is shown that in metal-free compositions NBTAT is significantly superior to ammonium perchlorate(AP),dinitramide ammonium salt(ADN),HMX,BTAT at all stages of rocket systems,and is comparable to the superdense CL-20 yielding to the latter at the lower stages and slightly winning at the upper stages. 展开更多
关键词 Nitrogen heterocycles quantum chemistry Enthalpy of formation 3 6-bis(2 2 2-trinitroethylnitramino)-1 2 4 5-tetrazine Crystal structure Energetic ability
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Improvement in the calculation of anti-Stokes energy transfer and experimental justification based on Er_(0.01)Yb_xY_(1 0.01 x)VO_4 crystal
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作者 陈晓波 卢建 +5 位作者 张蕴芝 徐小灵 冯宝华 王策 Gregory J. Salamo 杨国建 《Chinese Physics B》 SCIE EI CAS CSCD 2010年第9期604-611,共8页
The improvement on the calculation of anti-Stokes energy transfer rate is studied in the present work. The additional proportion coefficient between Stokes and anti-Stokes light intensities of quantum Raman scattering... The improvement on the calculation of anti-Stokes energy transfer rate is studied in the present work. The additional proportion coefficient between Stokes and anti-Stokes light intensities of quantum Raman scattering theory as compared with the classical Raman theory is introduced to successfully describe the anti-Stokes energy transfer. The theoretical formula for the improvement on the calculation of anti-Stokes energy transfer rate is derived for the first time in this study. The correctness of introducing coefficient exp{△E/kT} from well-known Raman scatter theory is demonstrated also. Moreover, the experimental lifetime measurement in Er0.01YbxY1-0.01-xVO4 crystal is performed to justify the validity of our important improvement in the original phonon-assisted energy transfer theory for the first time. 展开更多
关键词 improvement of anti-Stokes energy transfer Raman scattering quantum and classical theory Er0.01YbxY1-0.01-xVO4 crystal
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Quantum Chemical Calculation on Preparation of YBa_2Cu_3O_(7-δ) Powders by Hydrolysis of Metal Alkoxides
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作者 尹周澜 李新海 +2 位作者 赵秦生 高孝恢 李晶 《Rare Metals》 SCIE EI CAS CSCD 1994年第1期72-76,共5页
The structural characteristics of different alkoxides of Y. Ba and Cu are studied with quantum chemi-cal CNDO /2 calculations. The relative hydrolysis rate coefficients k_M of them are obtained according tothe relati... The structural characteristics of different alkoxides of Y. Ba and Cu are studied with quantum chemi-cal CNDO /2 calculations. The relative hydrolysis rate coefficients k_M of them are obtained according tothe relationship between frontier orbitals and organic chemical reactions. Based on the above results. properexperimental conditions for the preparation of homogeneous ultra-purity. submicro high-T_cYBa_2Cu_3O_(7-δ) superconducting powders are proposed. 展开更多
关键词 Metal alkoxides. Hydrolysis. YBa_2Cu_3O_(7-δ) quantum chemical calcu-lation
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Evaluation of Quantum Chemical Methods and Basis Sets Applied in the Molecular Modeling of Artemisinin
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作者 Cleydson B. R. dos Santos Cleison C. Lobato +5 位作者 Josinete B. Vieira Davi S. B. Brasil Alaan U. Brito Williams J. C. Macêdo José Carlos T. Carvalho José C. Pinheiro 《Computational Molecular Bioscience》 2013年第3期66-79,共14页
In this paper, we evaluate semiempirical methods (AM1, PM3, and ZINDO), HF and DFT (B3LYP) in different basis sets to determine which method best describes the sign and magnitude of the geometrical parameters of artem... In this paper, we evaluate semiempirical methods (AM1, PM3, and ZINDO), HF and DFT (B3LYP) in different basis sets to determine which method best describes the sign and magnitude of the geometrical parameters of artemisinin in the region of the endoperoxide ring compared to crystallographic data. We also classify these methods using statistical analysis. The results of PCA were based on three main components, explaining 98.0539% of the total variance, for the geometrical parameters C3O13, O1O2C3, O13C12C12a, and O2C3O13C12. The DFT method (B3LYP) corresponded well with the experimental data in the hierarchical cluster analysis (HCA). The experimental and theoretical angles were analyzed by simple linear regression, and statistical parameters (correlation coefficients, significance, and predictability) were evaluated to determine the accuracy of the calculations. The statistical analysis exhibited a good correlation and high predictive power for the DFT (B3LYP) method in the 6-31G** basis set. 展开更多
关键词 ARTEMISININ MOLECULAR Modeling quantum CHEMICAL Methods STATISTICAL Analysis B3LYP/6-31G**
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The “Non-Locality” of Entangled States Is Seeming Phenomenon
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作者 Marat Guryev 《Journal of Applied Mathematics and Physics》 2017年第9期1791-1796,共6页
EPR raised fundamental problems of non-locality (NL) in the case of entangled states (ES) 82 years ago. These problems were not solved until now. EPR and their followers used and would continue to use calculation meth... EPR raised fundamental problems of non-locality (NL) in the case of entangled states (ES) 82 years ago. These problems were not solved until now. EPR and their followers used and would continue to use calculation methods that were available at that time. However, we can easily explain this observable NL as a trivial result of conservation laws (CL) within modern quantum mechanics (MQM). But application of CL requires materialistic descriptions of reality in a micro world in contrast to so-called quantum measurement theory (QMT), which was created mainly in the times of EPR and is widely accepted until now. We have to use a materialistic description, just as many physicists who actually work with high precision do by default. In this article, practical examples are given for real, precise measurements of wave functions of molecules and crystals, which, of course, were not known to EPR and were not noticed by their followers. We should acknowledge that QMT is merely an unneeded complication of simple relations of MQM. NL is the seeming result of these complications. 展开更多
关键词 NON-LOCALITY ENTANGLED States quantum MEASUREMENT Theory EPR Electron DIFFRACTION Neutron DIFFRACTION y - RAY DIFFRACTION MEASUREMENT of Wave Function
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Crystal and Molecular Structure, and Spectral Characteristics of Sodium 3,5-Bis(Hydroxyimino)-1-Methyl-2,4,6-Trioxocyclohexanide
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作者 Olga Kovalchukova Nguyen Dinh Do +6 位作者 Adam Stash Vitaly Bel’sky Paul Strashnov Andrew Alafinov Oleg Volyansky Svetlana Strashnova Konstantin Kobrakov 《Crystal Structure Theory and Applications》 2012年第3期46-51,共6页
Sodium 3,5-bis(hydroxyimino)-1-methyl-2,4,6-trioxocyclohexanide C7H5N2NaO5 (I) has been isolated as the only product of the reaction of nitrosation of methylphloroglucinol. The structure of the titled compound has bee... Sodium 3,5-bis(hydroxyimino)-1-methyl-2,4,6-trioxocyclohexanide C7H5N2NaO5 (I) has been isolated as the only product of the reaction of nitrosation of methylphloroglucinol. The structure of the titled compound has been determined from single crystal X-ray diffraction data. The hydrated C7H5N2NaO52.5H2O crystallizes in the monoclinic space group C2/c, with a(?) 16.408(3);b(?) 12.446(3);c(?) 13.716(3);(o) 126.34(3). The planar organic anion exists in a triketo-dihydroxyimino form with the C–O and C–N distances from 1.220(2) to 1.271(2)?? and from 1.292(2) to 1.293?? respectively. In the IR spectrum of I, the sharp absorption band occurred at 1681 cm-1 due to C=O stretching indicating the strong H-interactions. The correlations of theoretical (DFT-B3LYP/aug-cc-pVDZ) and experimental UV-vis absorption spectra in neutral and alkaline ethanolic solutions showed the existence of hydroxyimino-nitroso tautomerism while ionization of I. 展开更多
关键词 SODIUM 3 5-Bis(Hydroxyimino)-1-Methyl-2 4 6-Trioxocyclohexanide CRYSTAL Structure IR SPECTRA Electronic Absorption SPECTRA quantum Chemical Modeling
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荷兰绿色建筑评价体系发展简析 被引量:2
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作者 叶青 李昕阳 +1 位作者 宋昆 赵强 《建筑节能》 CAS 2018年第5期25-34,共10页
绿色建筑评价体系是衡量建筑环境性能并指导规划建设及运营管理的工具。根据国际能源机构(IEA)的调查统计,国际上与绿色建筑评价体系相关的方法、框架和工具就有100种以上。既有研究对发达国家典型评价体系,尤其对英、美、日、新加坡等... 绿色建筑评价体系是衡量建筑环境性能并指导规划建设及运营管理的工具。根据国际能源机构(IEA)的调查统计,国际上与绿色建筑评价体系相关的方法、框架和工具就有100种以上。既有研究对发达国家典型评价体系,尤其对英、美、日、新加坡等国的绿色建筑理念、评价体系的分析介绍较多,且较为深入。而我国目前对于荷兰绿色建筑及建筑评价研究较少。通过对荷兰绿色建筑相关法律法规梳理,详细介绍在荷兰建筑业市场应用最为广泛的GreenCalc+、Eco-Quantum、Breeam-NL、GPR评价体系,并从发展历程、评价视域、体系设置、结果表达等方面对其进行优缺点和发展现状进行分析研究,借鉴先进经验和成果,如保持评价体系的动态更新,提高评价体系的可操作性,丰富评价对象,加强评价体系的国际推广等,以期对中国绿色建筑评价体系研究有所裨益。 展开更多
关键词 绿色建筑 评价体系 GreenCalc + eco-quantum Breeam-NL GPR
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基于密度泛函理论的SF_6潜在替代气体筛选 被引量:18
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作者 陈庆国 邱睿 +2 位作者 林林 程嵩 张聪 《高电压技术》 EI CAS CSCD 北大核心 2019年第4期1026-1033,共8页
目前在研的SF_6替代气体存在沸点θ_b过高、与缓冲气体混合后绝缘强度E_R降低等问题,仍需要寻找新型替代气体。为此,基于气体中载流子碰撞过程分析,找出第1电离能ε、分子电负性χ和分子直径D_w3个与气体绝缘强度相关的参数,并采密度泛... 目前在研的SF_6替代气体存在沸点θ_b过高、与缓冲气体混合后绝缘强度E_R降低等问题,仍需要寻找新型替代气体。为此,基于气体中载流子碰撞过程分析,找出第1电离能ε、分子电负性χ和分子直径D_w3个与气体绝缘强度相关的参数,并采密度泛函理论(DFT)下的B3LYP方法及6-311G+(d,p)基组对37种气体的上述参数进行计算。通过多元非线性拟合得到了气体绝缘强度预测模型,模型可决系数R^2达到0.90;并根据10个未代入拟合的气体绝缘强度数据对预测模型进行了校验。结果显示,在对弱极性非对称分子的D_w进行修正后,模型的准确性和适用性得到提高,R^2可达0.85。通过对θ_b已知的待选气体进行E_R的预测,并根据替代潜能因子Kp,从137种待选气体中筛选出了5种具有较高替代潜能的绝缘气体。 展开更多
关键词 绝缘强度预测 潜在绝缘气体 环保型管道输电 密度泛函理论 量子化学
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水相中羟基自由基与磺胺甲恶唑反应机理的理论研究
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作者 郑丽英 杨基峰 +4 位作者 欧利辉 靳俊玲 李静雅 李超群 罗胜联 《环境化学》 CAS CSCD 北大核心 2022年第12期3965-3972,共8页
本研究采用量子化学计算研究了羟基自由基引发的磺胺甲恶唑加成反应与抽氢反应的机理,系统考察了水相中的反应动力学,应用ECOSAR软件预测并评估了加成产物的生态毒性.研究结果表明,磺胺甲恶唑的C_(8)、C_(12)及C_(16)等位点的平均局部... 本研究采用量子化学计算研究了羟基自由基引发的磺胺甲恶唑加成反应与抽氢反应的机理,系统考察了水相中的反应动力学,应用ECOSAR软件预测并评估了加成产物的生态毒性.研究结果表明,磺胺甲恶唑的C_(8)、C_(12)及C_(16)等位点的平均局部离子化能较低,说明它们更易与羟基自由基发生反应.除C17和H21外,其他位点的反应过程均放热,并且C1位点的加成反应与C—S键的裂解存在协同效应;加成反应和抽氢反应的活化自由能在4.0—28.6 kcal·mol^(−1)之间变化,最小值和最大值分别发生在C_(8)和H9位点;虽然反应的速率常数达到4.97×10^(12) L·mol^(−1)·s^(−1),但因受扩散控制使其在水相中的表观反应速率常数仅为8.68×10^(9) L·mol^(−1)·s^(−1).毒性预测结果显示,尽管大部分加成产物的生态毒性较母体化合物低,但C_(8)、C_(12)和C_(16)位点上的加成产物仍具有较高的生态毒性风险. 展开更多
关键词 羟基自由基 磺胺甲恶唑 量子化学 动力学 生态毒性
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A novel integrated quantum circuit for high-order W-state generation and its highly precise characterization 被引量:1
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作者 Ren Heilmann Markus Gra¨ fe +1 位作者 Stefan Nolte Alexander Szameit 《Science Bulletin》 SCIE EI CAS CSCD 2015年第1期96-100,共5页
Multipartite entangled states like the W-class are of growing interest since they exhibit a variety of possible applications ranging from quantum computation to genuine random number generation. Here, we present a uni... Multipartite entangled states like the W-class are of growing interest since they exhibit a variety of possible applications ranging from quantum computation to genuine random number generation. Here, we present a universal setup to generate high-order single photon W-states based on three-dimensional integrated-photonic waveguide struc- tures. Additionally, we present a novel method to charac- terize the device's unitary by means of classical light only. 展开更多
关键词 quantum information - Integrated optics quantum computing Entangled states
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