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THE　STUDY　OF　ESR　SPECTRA　IN　SOLID　STATR　AND　HIGH　VISCOSITY　SOLUTION　FOR　PROPAGATING　RADICAL　OF　POLYSTYRRNE

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Chinese Chemical Letters 1994年第8期5卷 695-696页

作者： you gang mao Rui Fang SONG Jia Cong SHEN (Key Laboratory for Molecular Spectra & Structure, Institute of Theoretical Chemistry, Jilin University ,Jilin University,Changchun,130023)

In this paper, the 3-line in solid and 12-line high-viscosity solution ESR spectra of the propagating radical of Polystyrene were Studied. The 3-line spectrum comes from the conformation of the radical R1 which usually corresponds to a 6-line typical spectrum but appear as an apparent 3-line spectrum in solid *** 12-line specturm comes from two speciesof radicals with the same conformation R2 but different G factor .R2 corresponds to a 8-line typical spectrum which appear as an apparen in the hing-viscosity solution. therefore, two apparent 6-line spectra of R2 with different g values form the 12-line spectrum.

关键词： ESR OF SPECTRA STUDY AND

昆明地区主要花卉蔬菜基地设施栽培土壤养分变化特点

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土壤 2004年第3期36卷 303-306页

作者：苏友波李刚毛昆明张乃明云南农业大学资源与环境学院昆明650201

昆明地区蔬菜、花卉种植以设施栽培为主,本文对不同棚龄的大棚设施土壤pH、全N、P、K、碱解N、速效K、有效P、交换性Ca、Mg等指标进行测定分析,结果表明:随棚龄年限的增长,耕层土壤pH值、有机质和土壤交换性Ca、Mg含量有降低的趋势,但... 详细信息

昆明地区蔬菜、花卉种植以设施栽培为主,本文对不同棚龄的大棚设施土壤pH、全N、P、K、碱解N、速效K、有效P、交换性Ca、Mg等指标进行测定分析,结果表明:随棚龄年限的增长,耕层土壤pH值、有机质和土壤交换性Ca、Mg含量有降低的趋势,但无论是露地还是盖棚土壤有机质(52.8 g/kg)都较20世纪80年代中期有较大幅度提高;耕层土壤和深层土壤,全N、有效N含量呈持续上升趋势。耕层土壤中,土壤速效K和速效P呈现明显的富集。

关键词：土壤养分土壤层次设施栽培土壤棚龄

J/ψProduction Associated with the W-Boson at the 7 TeV Large Hadron Collider

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Chinese Physics Letters 2013年第9期30卷 39-42页

作者： SONG mao LI gang MA Wen-Gan ZHANG Ren-you GUO Lei GUO Jian-you School of Physics and Material Science Anhui UniversityHefei 230039 Department of Modern Physics University of Science and Technology of ChinaHefei 230026

We calculate the complete next-to-leading order(NLO)QCD corrections to J/ψ+W associated production within the factorization formalism of nonrelativistic QCD at the 7 TeV Large Hadron *** provide the numerical results for the leading-order(LO),NLO QCD corrected differential cross sections of the J/ψtransverse momentum by adopting the event selection criteria requested by the ATLAS *** is found that the differential cross section at the LO is significantly enhanced by the NLO QCD corrections.

关键词： correction momentum transverse

Theoretical investigation on water/metal fuel ramjet motor-thermodynamic cycle and thermodynamic calculation

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航空动力学报 2010年第5期25卷 1129-1138页

作者： YANG Ya-jing HE mao-gang School of Aerospace Xi'an Jiaotong UniversityXi'an 710049China State Key Laboratory of Multiphase Flow in Power Engineering School of Energy and Power EngineeringXi'an Jiaotong UniversityXi'an 710049China

For achieving high-speed requirement of underwater vehicle,a conceptual engine,which utilizes the hydroreactive characteristic of several metals under supercavitation environment,has been put forward. Especially,in order to obtain specific impulse as great as possible,a dual water injection system is taken into account. Then thermodynamic cycle model,which lead the improvement of power plant and energy system,is introduced in detail,and thermal efficiency is also analyzed. Furthermore,for investigating the performance of this kind of engine system,detailed thermodynamic calculation and analysis are achieved. Especially,regarding hydroreactive metal fuel Mg/AP/HTPB as our target fuel-rich propellant,considering its obvious deficient oxygen property and the energy property of magnesium/water reaction,theoretical calculation method is established by integrating chemical non-equilibrium with chemical equilibrium. Accordingly,low limit of primary water/fuel ratio is determined. In addition,the qualitative and quantitative relationship of performance parameters,such as theoretical specific impulse,nozzle exit temperature,characteristic velocity,etc.,versus water/fuel ratio is investigated respectively.

关键词： hydroreactive metal fuel water ramjet thermodynamic cycle thermal efficiency specific impulse

Hydrophobic terminal group of surfactant initiating micellization as revealed by^1H NMR spectroscopy

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Chinese Chemical Letters 2017年第7期28卷 1413-1416页

作者： gang-Jin Yu Xiao-Ying Chen Shi-Zhen mao Mai-Li Liu you-Ru Du State Key Laboratory of Magnetic Resonance and Atomic and Molecular Physics Wuhan Institute of Physics and MathematicsChinese Academy of SciencesWuhan 430071China University of Chinese Academy of Sciences Beijing 100029China

The critical aggregation concentration（CAC） of four with three kinds of conventional surfactants, namely,two cationic surfactants [hexadecyltrimethyl ammonium bromide（CTAB） and tetradecyltrimethyl ammonium bromide（TTAB）], one anionic surfactant [sodium dodecyl sulfate（SDS）], and a nonionic surfactant [Triton X-100（TX-100）], were determined by variation of ^1H chemical shifts with surfactant concentrations. Results show that the CAC values of protons at different positions of the same molecule are different, and those of the terminal methyl protons are the lowest, respectively, which suggests that the terminal groups of the alkyl chains aggregates first during micellization. Measurement of the transverse relaxation time（T2） of different protons in SDS also show that the terminal methyl protons start to decrease with the increase in concentration first, which supports the above mentioned tendency.

关键词： 1H NMR Surfactants Critical aggregation concentration Hydrophobic terminal group Micellization

Next-to-leading order QCD corrections to Higgs boson decay to quarkonium plus a photon

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Chinese Physics C 2016年第12期40卷 46-51页

作者： Chao Zhou mao Song gang Li Ya-Jin Zhou Jian-you Guo School of Physics and Material Science Anhui University Hefei 230601 China School of Physics Shandong University Jinan 250100 China

In this paper, we investigate the decay of the Higgs boson to J/ψ（γ ） plus a photon based on NRQCD factorization. For the direct process, we calculate the decay width up to QCD NLO. We find that the decay width for process H → J/ψ（γ ）＋γ direct production at the LO is significantly reduced by the NLO QCD corrections. For the indirect process, we calculate the H→γ＊γ, with virtual 7 substantially decaying to J/ψ（γ）, including all the SM Feynman diagrams. The decay width of indirect production is much larger than the direct decay width. Since it is very clean in experiment, the H →J/ψ（ γ）＋γ decay could be observable at a 14 TeV LHC and it also offers a new way to probe the Yukawa coupling and New Physics at the LHC.

关键词： Higgs boson heavy quarkonium NLO QCD

Searches for dark matter via charged Higgs pair production in the Inert Doublet Model at a γγ collider

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Chinese Physics C 2021年第10期45卷 16-24页

作者： Guo-He Yang mao Song gang Li Yu Zhang Jian-you Guo School of Physics and Material Science Anhui UniversityHefei 230601China School of physics Huazhong University of Science and TechnologyHefei 230601China Institutes of Physical Science and Information Technology Anhui UniversityWuhan 430074China

The Inert Doublet Model(IDM)is one of the simplest extensions beyond the Standard Model(SM)with an extended scalar sector,which provides a scalar dark matter particle *** this study,we investigated the double charged Higgs production at aγγ*** scanning the whole parameter space,we obtained the parameter points corresponding to the correct relic abundance of dark *** applying all theoretical and experimental constraints,the parameter space for the existence of dark matter was extremely *** performed an analysis of the signal of H+H-production in the IDM and the SM background,with the optimized selection conditions chosen for the kinematic variables to maximize the signal *** the signal with the background,we obtained the parameter points that may be detected in futureγγcollider experiments.

关键词： dark matter IDM large hadron collider

Anti-proliferative Properties of Schinensilactone A,A Schinortriterpenoid with 7,8-Seco-1,8-cyclo Scaffold against Caco-2 by Inducing Cell Apoptosis from the Leaves of Schisandra chinensis

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Chinese Journal of Chemistry 2022年第11期40卷 1331-1336,I0002页

作者： Yan Liu Guo-Zhen Liu Xiao-mao Li Peng Jiang Yong-gang Xia Hai-Xue Kuang Bing-you Yang Key Laboratory of Basic and Application Research of Beiyao(Heilongjiang University of Chinese Medicine) Ministry of EducationHarbinHeilongjiang 150040China

A novel schinortriterpenoid(SNT),schinensilactone A(1),characterized by a unique 7,8-seco-1,8-cyclo-schisanartane scaffold,was isolated from the leaves of Schisandra chinensis(Turcz.)Baill,together with a new SNT(schinensilactone B,2)and two known(3,4).Their structures were elucidated using spectroscopy and X-ray ***,a hypothetical biosynthetic pathway for 1 was postulated due to its novel carbon *** addition,1 exhibited significant anti-proliferative activity against Caco-2 cells originat-ing from five different tumor cell lines,and its preliminary mechanism of action was investigated with respect to the expression of apoptosis-related proteins,including P53,Caspase 3,Bax,PUMA,and *** biological activities would further our understanding of the food function of Schisandra chinensis leaves.

关键词： Schinensilactone A Schinensilactone B Natural products Terpenoids Biological activity

Nanoscale precipitates and comprehensive strengthening mechanism in AISI H13 steel

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International Journal of Minerals,Metallurgy and Materials 2016年第9期23卷 1056-1064页

作者： Wen-wen mao An-gang Ning Han-jie Guo School of Metallurgical and Ecological Engineering University of Science and Technology BeijingBeijing 100083China Beijing Key Laboratory of Special Melting and Reparation of High-end Metal Materials Beijing 100083China College of Materials Science and Engineering Taiyuan University of TechnologyTaiyuanShanxi 030024China

The effects of heat treatment on the precipitates and strengthening mechanism in AISI H13 steel were investigated. The results showed that the presence of nanoscale precipitates favorably affected grain refinement and improved the yield strength. The volume fraction of precipitates increased from 1.05% to 2.85% during tempering, whereas the average precipitate size first decreased then increased during tempering. Contributions to the yield strength arising from the various mechanisms were calculated quantificationally, and the results demonstrated that grain refinement and dislocation density most strongly influenced the yield strength. In addition, under the interaction of average size and volume fraction, precipitates＇ contribution to the yield strength ranged from 247.9 to 378.5 MPa. Finally, a root-mean-square summation law of σ = σg ＋ σs ＋（σd^2 ＋ σp^2）^1/2, where σg, σs, σd, and σp represent the contributions of fine-grain strengthening, solid-solution strengthening, dislocation strengthening, and precipitation strengthening, respectively, was confirmed as the most applicable for AISI H13 steel, which indicates a strong link between precipitates and dislocations in AISI H13 steel.

关键词： die steel precipitates strengthening dislocation