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Acta Mechanica Solida Sinica 2021年第1期34卷 124-136页

作者： Xue-Qian Fang Yao Ning Shao-Pu Yang hai-hua wang State Key Laboratory of Mechanical Behavior and System Safety of Traffic Engineering Structures Shijiazhuang Tiedao UniversityShijiazhuang050043China Department of Engineering Mechanics Shijiazhuang Tiedao UniversityShijiazhuang050043China Hebei Key Laboratory for Mechanics of Smart Materials and Structures Shijiazhuang050043China School of Mechanical Engineering Shijiazhuang Tiedao UniversityShijiazhuang050043China

The dynamic contact behavior of worn bearings with elastoplastic functionally graded coating is studied,and the interacting effect between worn band and functionally graded surface is *** surface deformation and roughness are included in the film *** mixed elastohydrodynamic lubrication combined with point contact model is introduced to analyze the oil pressure in the contact *** using the Fourier transform method and Papkovich-Neuber potential function,the displacements and stress fields in the elastoplastic functionally graded coating are *** second-order central difference method is used to solve the Reynolds *** is found that the repeated surface interaction can result in the sharp increase in pressure in bearings,and the oil pressure increases with increasing graded *** entrainment of oil in the inlet and outlet zones becomes more evident if a large graded index is selected.

关键词： Wear bearings Contact behavior Elastoplastic functionally graded surface Mixed elastohydrodynamic lubrication.Central difference method

Effect of sintering temperature on the electrolysis of TiO_2

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International Journal of Minerals,Metallurgy and Materials 2012年第7期19卷 636-641页

作者： Ze-quan Li Li-yue Ru Cheng-guang Bai Na Zhang hai-hua wang College of Chemistry and Chemical Engineering Chongqing University Chongqing 400044 China College of Materials Science and Engineering Chongqing University Chongqing 400044 China

The effects of sintering temperature on the microstructure and the conductivity of TiO2 cathodes were studied by examining the phase composition, microstructure, and element contents of the sintered cathodes and the cathodic products using X-ray diffraction and scan- ning electronic microscopy-energy dispersive spectrometry. The oxygen vacancy, conductivity, average pore diameter, and specific surface area of the sintered cathodes were detected by X-ray photoelectron spectroscopy, four-point probe, and ASPA 2010. The results showed that TiO2 phase transformations occurred, and oxygen vacancies formed with the increase of sintering temperature. The cathodic conductivity improved, but the average pore diameter and the effective response area of the TiO2 cathode were reduced when the sintering temperature in- creased. These phenomena could weaken the contact between reaction ions and electrons and also had the same effect on the cathodes and the molten salt. Moreover, they were disadvantageous to ion migration, so a lower sintering temperature was favorable for the microstructure of electrolysis. Consequently, the cathodic conductivity may be improved, but the microstrucatre became compact with the increase of sin- tering temperature. The cathodic products at different temperatures indicated that the cathodic conductivity was more important for electroly- sis.

关键词： titanium dioxidegelectrolysis sintering microstructure

Epigenetic Regulation of Amyloid-beta Metabolism in Alzheimer’s Disease

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Current Medical Science 2020年第6期40卷 1022-1030页

作者： Chuan HE Zhong-sheng huaNG Chao-chao YU hai-hua wang hua ZhOU Li-hong KONG Hubei University of Chinese Medicine Wuhan 430060China Department of Tuina Shenzhen Traditional Chinese Medicine HospitalShenzhen 518000China The 4th Clinical College of Guangzhou University of Chinese Medicine Shenzhen 518000China Hospital of Traditional Chinese Medicine of Fengrun District Tangshan 064000China

Senile plaques(SPs)are one of the pathological features of Alzheimer’s disease(AD)and they are formed by the overproduction and aggregation of amyloid-beta(Aβ)peptides derived from the abnormal cleavage of amyloid precursor protein(APP).Thus,understanding the regulatory mechanisms during Aβ metabolism is of great importance to elucidate AD *** studies have shown that epigenetic modulation-including DNA methylation,non-coding RNA alterations,and histone modifications-is of great significance in regulating Aβ *** this article,we review the aberrant epigenetic regulation of Aβ metabolism.

关键词： Alzheimer’s disease amyloid-β epigenetics DNA methylation microRNAs histone modifications

Copolymerization of Ethylene/1-Butene with Heterogeneous TiCl4/(α-Diimine)nickel(Ⅱ) Complex Combined Catalyst

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Chinese Chemical Letters 2003年第9期14卷 911-913页

作者： Shao Quan LIN, Qi Xing ZHANG, hai hua wang Institute of Polymer Science, Zhongshan University, Guangzhou 510275 Institute of Polymer Science Zhongshan University Guangzhou 510275 China

The new type heterogeneous combined catalyst system TiCl4-(α-diimine)nickel(Ⅱ) complexes/MgCl2-SiO2/AlR3 was prepared. Ethylene and 1-butene were copolymerized with the catalysts in slurry phase. It was found that with combined catalyst, the copolymers with lower density and higher branched degree were obtained. 13CNMR results showed that in the obtained copolymers existed not only ethyl but also some other kinds of branches due to the fact that ethylene exhibits the behavior of oligomerization and copolymerization in-situ with combined catalysts.

关键词： Combined catalyst oligomerization and copolymerization in-situ copolymers.

Dynamic manipulation of probe pulse and coherent generation of beating signals based on tunneling-induced inference in triangular quantum dot molecules

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Chinese Physics B 2020年第3期29卷 209-214页

作者： Nuo Ba Jin-You Fei Dong-Fei Li Xin Zhong Dan wang Lei wang hai-hua wang Qian-Qian Bao National Demonstration Center for Experimental Physics Education College of PhysicsJilin Normal UniversitySiping 136000China College of Physics Jilin UniversityChangchun 130012China College of Physics Liaoning UniversityShenyang 110036China

We investigate the dynamic propagation of a probe field via the tunneling-induced interference effect in a triple model of quantum dot molecules. By theoretical analysis and numerical simulation, we find that the number of transparency window relate to the energy splitting and the group velocity of probe field can be effectively controlled by the tunneling coupling intensity. In addition, in the process of light storage and retrieval, when the excited states have no energy splitting in the storage stage but opposite values of the energy splitting in the retrieval stage, the beating signals can be generated.

关键词： coherent optical effects electromagnetically induced transparency triple quantum dots

Sources of calcium in agonist-induced contraction of rat distal colon smooth muscle in vitro

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World Journal of Gastroenterology 2008年第7期14卷 1077-1083页

作者： hua Zhou De-Hu Kong Qun-Wan Pan hai-hua wang Department of Physiology Wannan Medical College Wuhu 241000 Anhui Province China Department of Physiology Anhui Medical University Hefei 230032 Anhui Province China

AIM: To study the origin of calcium necessary for agonist-induced contraction of the distal colon in ***: The change in intracellular calcium concentration ([Ca2+]i) evoked by elevating external Ca2+ was detected by fura 2/AM fluorescence. Contractile activity was measured with a force displacement transducer. Tension was continuously monitored and recorded using a Powerlab 4/25T data acquisition system with an ML110 bridge bioelectric physiographic ***: Store depletion induced Ca2+ influx had an effect on [Ca2+]i. In nominally Ca2+-free medium, the sarco-endoplasmic reticulum Ca2+-ATPase inhibitor thapsigargin (1 μmol/L) increased [Ca2+]i from 68 to 241 nmol/L, and to 458 (P < 0.01) and 1006 nmol/L (P < 0.01), respectively, when 1.5 mmol/L and 3.0 mmol/L extracellular Ca2+ was reintroduced. Furthermore, the change in [Ca2+]i was observed with verapamil (5 μmol/L), La3+ (1 mmol/L) or KCl (40 mmol/L) in the bathing solution. These channels were sensitive to La3+ (P < 0.01), insensitive to verapamil, and voltage independent. In isolated distal colons we found that in normal Krebs solution, contraction induced by acetylcholine (ACh) was partially inhibited by verapamil, and the inhibitory rate was 41% (P < 0.05). On the other hand, in Ca2+-free Krebs solution, ACh induced transient contraction due to Ca2+ release from the intracellular stores. The transient contraction lasted until the Ca2+ store was depleted. Restoration of extracellular Ca2+ in the presence of atropine produced contraction, mainly due to Ca2+ influx. Such contraction was not inhibited by verapamil, but was decreased by La3+ (50 μmol/L) from 0.96 to 0.72 g (P < 0.01). CONCLUSION: The predominant source of activator Ca2+ for the contractile response to agonist is extracellular Ca2+, and intracellular Ca2+ has little role to play in mediating excitation-contraction coupling by agonists in rat distal colon smooth muscle in vitro. The influx of extracellular Ca2+ is mainly mediated

关键词： Distal colon Source of Ca^2+ Storeoperated Ca^2+ channel Voltage-operated Ca^2+ channel Acetylcholine

Origin,discovery,exploration and development status and prospect of global natural hydrogen under the background of“carbon neutrality”

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China Geology 2022年第4期5卷 722-733页

作者： Qian-ning Tian Shu-qing Yao Ming-juan Shao Wei Zhang hai-hua wang Geoscience Documentation Center China Geological SurveyMinistry of Natural ResourcesBeijing 100083China National Geological Library of Chin1 2eijing 100083China

Global energy structure is experiencing the third transition from fossil energy to non-fossil energy,to solve future energy problems,cope with climate change,and achieve net-zero emissions targets by *** is considered to be the most potential clean energy in this century under the background of carbon *** present,the industrial methods for producing hydrogen are mainly by steam-hydrocarbon(such as coal and natural gas)reforming and by electrolysis of water,while the exploration and development of natural hydrogen had just *** to this literature review:(1)Natural hydrogen can be divided into three categories,including free hydrogen,hydrogen in inclusions and dissolved hydrogen;(2)natural hydrogen could be mainly from abiotic origins such as by deep-seated hydrogen generation,water-rock reaction or water radiolysis;(3)natural hydrogen is widely distributed and presents great potential,and the potential natural hydrogen sources excluding deep source of hydrogen is about(254±91)×10^(9) m^(3)/a according to a latest estimate;(4)at present,natural hydrogen has been mined in Mali,and the exploration and development of natural hydrogen has also been carried out in Australia,Brazil,the United States and some European countries,to find many favorable areas and test some technical methods for natural hydrogen *** hydrogen is expected to be an important part of hydrogen energy production in the future energy *** on a thorough literature review,this study introduced the origin,classification,and global discovery of natural hydrogen,as well as summarized the current global status and discussed the possibility of natural hydrogen exploration and development,aiming to provide reference for the future natural hydrogen exploration and development.

关键词： Carbon neutrality Energy transition New energy Hydrogen energy Natural hydrogen Occurrence Genesis Resources Exploration and development Potential

Gas Phase Polymerisation of Ethylene with Supported Titanium-Nickel Catalysts

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Chinese Chemical Letters 2000年第1期11卷 85-86页

作者： Jin Min HU hai hua wang Jiang Li WU Qi Xing ZHANG(Institute of polymer Science. Zhongshan University, Guangzhou 510275) Institute of Polymer Science Zhongshan University Guangzhou 510275 China

A new ditransition-metal catalyst system TiC1.-NiC1_2,/MgC1_2,-SiO_2,/AlR_3 was prepared. Gas phase polymerization of ethylene with the catalysts has been studied. The kinetic curves of gas phase polymerization showed a decline. The catalysts efficiency and polymerization reaction rates have a optimum value when Ni content of the catalysts was 12.5%(mol).The products obtained are branched polyethylene.

关键词： Gas phase polymerization NiCl_2 catalysts branched polyethylene.

Effectively modulating spatial vortex four-wave mixing in a diamond atomic system

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Chinese Physics B 2024年第4期33卷 473-478页

作者：巴诺姜明奇费金友王丹蒋海林王磊王海华 National Demonstration Center for Experimental Physics Education College of PhysicsJilin Normal UniversitySiping 136000China College of Physics Jilin UniversityChangchun 130012China

Due to the spatial characteristics of orbital angular momentum,vortex fields can be applied in the fields of quantum storage and quantum *** study the realization of spatially modulated vortex fields based on four-wave mixing in a four-level atomic system with a diamond *** intensity and spiral phase of the vortex field are effectively transferred to the generated four-wave mixing *** changing the detuning of the probe field,the phase and intensity of the generated vertex four-wave mixing field can be *** the probe field takes a large detuning value,the spatial distribution of the intensity and phase of the vertex four-wave mixing field can be effectively tuned by adjusting the Rabi frequency or detuning value of the coupled *** the same time,we also provide a detailed explanation based on the dispersion relationship,and the results agree well with our simulation results.

关键词： coherent optical effects four-wave mixing orbital angular momentum

A New Porous MOF with Highly Efficient Selectivity and Chemical Conversion for CO2

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A New Porous MOF with Highly Efficient Selectivity and Chemi...