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Nanoscale mass sensing based on vibration of single-layered graphene sheet in thermal environments 被引量:2
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作者 S.Ahmad Fazelzadeh Esmaeal Ghavanloo 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 2014年第1期84-91,共8页
Based on vibration analysis, single-layered graphene sheet (SLGS) with multiple attached nanoparticles is developed as nanoscale mass sensor in thermal environments. Graphene sensors are assumed to be in simplysuppo... Based on vibration analysis, single-layered graphene sheet (SLGS) with multiple attached nanoparticles is developed as nanoscale mass sensor in thermal environments. Graphene sensors are assumed to be in simplysupported configuration. Based on the nonlocal plate the- ory which incorporates size effects into the classical theory, closed-form expressions lot the frequencies and relative fre- quency shills of SLGS-based mass sensor are derived using the Galerkin method. The suggested model is justified by a good agreement between the results given by the present model and available data in literature. The effects of tem- perature difference, nonlocal parameter, the location of the nanoparticle and the number of nanoparticles on the relative frequency shift of the mass sensor are also elucidated. The obtained results show that the sensitivity of the SLGS- based mass sensor increases with increasing temperature difference. 展开更多
关键词 Vibration - Single-layered graphene sheet. Ther- mal environment - Nonlocal elasticity theory Relative frequency shift
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DFT Studies on Thermal Stabilities,Electronic Structures,and ^(13)C Chemical Shifts of C_(24)O_2 Based on Fullerene C_(24)(D_6) 被引量:2
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作者 王振 张静 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2011年第5期666-671,共6页
Quantum chemical calculations on some possible equilibrium geometries of C24O2 isomers derived from C24 (D6) and C24O have been performed using density functional theory (DFT) method. The geometric and electronic ... Quantum chemical calculations on some possible equilibrium geometries of C24O2 isomers derived from C24 (D6) and C24O have been performed using density functional theory (DFT) method. The geometric and electronic structures as well as the relative energies and thermal stabilities of various C24O2 isomers at the ground state have been calculated at the B3LYP/6-31G(d) level of theory. And the 1,4,2,5-C24O2 isomer was found to be the most stable geometry where two oxygen atoms were added to the longest carbon-carbon bonds in the same pentagon from a thermodynamic point of view. Based on the optimized neutral geometries, the vertical ionization potential and vertical electron affinity have been obtained. Meanwhile, the vibrational frequencies, IR spectrum, and 13C chemical shifts of various C24O2 isomers have been calculated and analyzed. 展开更多
关键词 C24O2 thermal stabilities 13C chemical shifts B3LYP/6-31G(d)
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Maintained Exposure to Spring Water but Not Double Distilled Water in Darkness and Thixotropic Conditions to Weak (~1 µT) Temporally Patterned Magnetic Fields Shift Photon Spectroscopic Wavelengths: Effects of Different Shielding Materials 被引量:2
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作者 N. J. Murugan L. M. Karbowski +1 位作者 R. M. Lafrenie M. A. Persinger 《Journal of Biophysical Chemistry》 2015年第1期14-28,共15页
Spring water but not double-distilled water was exposed, in darkness, to a temporally patterned weak magnetic field that has been shown to affect planarian behavior and slow the rate of cancer cell proliferation. Expo... Spring water but not double-distilled water was exposed, in darkness, to a temporally patterned weak magnetic field that has been shown to affect planarian behavior and slow the rate of cancer cell proliferation. Exposure to the magnetic field caused a reliable shift in the peak (longer) wave-length of ~10 nm for fluorescence emissions and a ~20% increase (~100 counts) in fluorescence intensity. Spectral analyses verified a shift of 5 and 10 nm, equivalent to ~1.5 × 10-20 J “periodicity” across the measured wavelengths, which could reflect a change in the an intrinsic energy as predicted by Del Giudice and Preparata and could correspond to two lengths of O-H bonds. Wrapping the water sample containers during exposure with copper foil, aluminum foil, or plastic altered these fluorescent profiles. The most conspicuous effect was the elimination of a ~280 nm peak in the UV-VIS emission spectra only for samples wrapped with copper foil but not aluminum or plastic. These results suggest that weak magnetic fields produce alterations in the water-ionic complexes sufficient to be reliably measured by spectrophotometry. Because the effect was most pronounced when the spring water was exposed in darkness and was not disturbed the role of thixotropic phenomena and Del Giudice entrapment of magnetic fields within coherent domains of Pollack virtual exclusion zones (EZ) may have set the conditions for subsequent release of the energy as photons. 展开更多
关键词 Water WEAK Magnetic Fields PHOTON Emissions DARKNESS Thixotropic Phenomena Copper Shielding Wavelength shift 10-20 Joules
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Sandwich Complexes of the As_4~(2-) Aromatic Ring with Some Transition Metals
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作者 李志伟 赵存元 +1 位作者 吴文胜 陈六平 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 北大核心 2008年第9期1097-1102,共6页
The equilibrium geometries, energies, harmonic vibrational frequencies, and nucleus independent chemical shifts (NICS) of the new type sandwich structures [As4MAs4]^n- (M = Fe, Co, Ni, Ru, Rh, Pd, Os, Ir and Pt; n ... The equilibrium geometries, energies, harmonic vibrational frequencies, and nucleus independent chemical shifts (NICS) of the new type sandwich structures [As4MAs4]^n- (M = Fe, Co, Ni, Ru, Rh, Pd, Os, Ir and Pt; n = 0, 1 or 2) are investigated at the B3LYP level. All the [As4MAs4]^n- species adopt staggered (D4d) conformations as their stable structures and eclipsed (D4h) conformations as their transition states, and once the sandwich complexes are formed, the As4^2- square properties remain unchanged. The NICS calculation confirms that the complexes of Fe, Co, and Ni are aromatic with negative NICS values, and those of Ru, Rh, and lx exhibit slight aromaticity, while those of Pd, Os, and Pt show slight antiaromaticity. 展开更多
关键词 As4^2- dianion AROMATICITY DFT calculation nucleus independent chemical shifts (NICS)
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^(13)C NMR Study of Ethylene/propylene/octene-1 Terpolymers Synthesized with TiCl_4/MgCl_2/ i -Bu_3Al as the Catalyst
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作者 LI San xi ZHOU Zi nan +3 位作者 XIAO Yan wen JING Feng ying PANG De ren HUANG Bao tong 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 2000年第3期236-245,共10页
The theory of chemical shift effect of substituent was applied to the assignment of the 13 C NMR spectra of the ethylene/propylene and ethylene/octene 1 copolymers. Using the parameters derived above a... The theory of chemical shift effect of substituent was applied to the assignment of the 13 C NMR spectra of the ethylene/propylene and ethylene/octene 1 copolymers. Using the parameters derived above and the DEPT technique, we then entirely assigned the 13 C NMR spectra of the ethylene/propylene/octene 1 terpolymers synthesized in the presence of the same heterogeneous supported Ziegler Natta catalyst, TiCl 4/MgCl 2/ i Bu 3Al. The present paper also covers the terpolymer composition and the monomer sequence distributions of a series of ethylene/propylene/octene 1 terpolymers. 展开更多
关键词 Chemical shift effect ^(13)C NMR Ethylene/propylene/octene^(-1) terpolymer
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Investigation on the Structure of Chute-feed and Card Auto-leveller and Their Selection of Technological Processes
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作者 程隆棣 《Journal of China Textile University(English Edition)》 EI CAS 1998年第3期62-65,共4页
Based on the structure of chute - feed and autoleveHer, an analysis of their working principle and the verification of their practical production results have been carried out. Finally, the future investigation direet... Based on the structure of chute - feed and autoleveHer, an analysis of their working principle and the verification of their practical production results have been carried out. Finally, the future investigation direetiom of chute - feed and card autuleveller are put forward. 展开更多
关键词 CHUTE - FEED CARD AUTO - leveller IRREGULARITY among shifts.
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章炳麟《成均图》的重新分析
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作者 刘艳梅 《河池学院学报》 2008年第6期52-56,共5页
章炳麟的《成均图》是其古音学研究的重要发明。梳理《成均图》韵转类别,对图中弇侈含义进行辨析;分析章氏建立韵转所依据的材料,并从同语异质视角考察大量韵转的语言经验事实依据。
关键词 章炳麟 《成均图》 韵转 方音 异质语言
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水煤气无变换脱硫工艺中水解催化剂的选择和应用 被引量:4
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作者 李秀峰 《中氮肥》 2011年第3期11-13,共3页
我公司200 kt/a焦炉煤气配水煤气制甲醇装置的水煤气系统采用无变换精脱硫工艺,结合实际应用经验,对各种类型脱硫水解催化剂的选择和应用进行了总结和论述,对已采用或者拟采用同类型工艺的企业具有一定的参考价值。
关键词 水煤气 无变换 精脱硫 催化剂 有机硫
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Computational evaluation concerning the deviation of the atoms in 1-and 4-postions on the six-member ring and the effects on ^(1)HNMR chemical shift
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作者 Asadollah FARHADI Mohammad Ali TAKASSI +1 位作者 Hamid Reza MEMARIAN Mousa SOLEYMANI 《Frontiers of Chemistry in China》 2011年第2期91-97,共7页
Density functional theory(DFT)calculations were carried out on some cyclohexane derivatives to investigate the deviation atoms on the 1-and 4-positions of chair plane.The deviations of chair plane of two position in t... Density functional theory(DFT)calculations were carried out on some cyclohexane derivatives to investigate the deviation atoms on the 1-and 4-positions of chair plane.The deviations of chair plane of two position in the cyclohexane derivatives were calculated at the B3LYP/6–31++G(d,p)level.Furthermore,we investigated the correlation between deviations of two positions from chair plane on the chemical shift hydrogen atoms on the 4-position. 展开更多
关键词 CYCLOHEXANE heterocyclohexane deviation B3LYP/6-31++G(d p) chemical shift
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浅析铅球、铁饼、标枪最后用力的转换衔接阶段常见错误
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作者 谢建安 《科教文汇》 2015年第20期75-76,共2页
本文主要通过对学生平时训练的观察,结合各方文献资料,进行研究与分析在投掷项目训练时,铅球、铁饼、标枪运动最后用力的转换衔接阶段的时机与正确方法,陈述正确转换阶段对稳定和提高成绩的重要性,怎样才能更有效地正确地完成转换阶段,... 本文主要通过对学生平时训练的观察,结合各方文献资料,进行研究与分析在投掷项目训练时,铅球、铁饼、标枪运动最后用力的转换衔接阶段的时机与正确方法,陈述正确转换阶段对稳定和提高成绩的重要性,怎样才能更有效地正确地完成转换阶段,避免在技术中出现空中换步和左脚着地或快或慢的现象,根据各方文献资料、逻辑分析法、观察法和实习实践后自我认识理解对此阶段进行分析研究,总结问题出现的原因及提出纠正的方法。 展开更多
关键词 铅球 铁饼 标枪 最后用力 转换衔接 空中换步 左脚支撑
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What do we learn from the ρ-π puzzle
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作者 李学潜 《Chinese Physics C》 SCIE CAS CSCD 2010年第2期267-269,共3页
The experimental observation indicates that the branching ratio of ψ'→ρπ is very small while the ρ-π channel is a main one in J/ψ decays. To understand the puzzle, various interpretations have been proposed. M... The experimental observation indicates that the branching ratio of ψ'→ρπ is very small while the ρ-π channel is a main one in J/ψ decays. To understand the puzzle, various interpretations have been proposed. Meanwhile according to the hadronic helicity selection rule, this decay mode should be suppressed. Numerical calculations are needed to determine how it is suppressed. We calculate the branching ratios of J/ψ→ρπ and ππ in the framework of QCD. The results show that the branching ratios are proportional to (mu+md/MJ/ψ)^2 for the ρπ mode and (mu-md/MJ/ψ)^2 for the ππ mode which is isospin violated. The theoretical prediction of the ratio of J/ ψ→ρπ is smaller than data, but not too small to invoke a completely new mechanism. Thus the puzzle is still standing even though we learn much knowledge towards the puzzle and this will help to finally interpret the puzzle and then gain a deeper insight to the heavy quarkonia. 展开更多
关键词 ρ-π puzzle hadronic helicity conservation final state interaction
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Transfer Pricing in BEPS Project and China's Response
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作者 徐海燕 《Frontiers of Law in China-Selected Publications from Chinese Universities》 2020年第2期142-168,共27页
A major concern on base erosion and profit shifting(BEPS)is transfer pricing,which is discussed in BEPS Action Items 8-10 and 13.Actions 8-10 contain revised guidance,which ensures that transfer pricing rules secure o... A major concern on base erosion and profit shifting(BEPS)is transfer pricing,which is discussed in BEPS Action Items 8-10 and 13.Actions 8-10 contain revised guidance,which ensures that transfer pricing rules secure outcomes that better align operational profits with the economic activities that generate them,as well as guidance on transactions involving cross-border commodity transactions and on low value-adding intra-group services.Action 13 contains a three-tiered standardized approach to transfer pricing documentation,including a minimum standard on country-by-country reports(CbCRs).However,the approach of Actions 8-10 still focuses on the restoration of the dysfunctional rules built on the arm's length principle,which is rooted in the principle of separate independent entity.The threshold of Action 13 excludes many large multinational enterprises(MNEs)from the CbCR requirement and deprives developing countries access to the information of MNEs below the threshold.Chapter 6 of the Chinese Corporate Income Tax Law,under the title"Special Tax Adjustments,"provided the legal foundations of transfer pricing and transfer pricing documentation in China.To effectively implement the BEPS package in China and to comprehensively update the existing Circular 2,the State Taxation Administration(STA)released a Discussion Draft of a Circular on Implementation Measures for Special Tax Adjustments in September 2015,ranging from Action 3(controlled foreign company rules),Action 8-10(aligning transfer pricing outcomes with value creation)to Action 13(transfer pricing documentation and country-by-country reporting)in details.Right now,a series of patches,such as the STA Bulletins 45,42,64,and 6,have been made to replace a substantial part of Circular 2. 展开更多
关键词 base erosion and profit shifting(BEPS) transfer pricing corporate income tax law Actions 8-10 Action 13
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