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Effects of irrigation efficiency on chemical transport processes

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Science China(Technological Sciences) 2009年第11期52卷 3287-3292页

作者： WANG kang ZHANG RenDuo sheng Feng State Key Laboratory of Water Resources and Hydropower Engineering Science Wuhan UniversityWuhan 430072China School of Environmental Science and Engineering Sun Yat-sen UniversityGuangzhou 510275China

Irrigation practices greatly affect sustainable agriculture development. In this study, we investigated the effects of irrigation efficiency on water flow and chemical transport in soils, which had significant impact on the environment. Field dye staining experiments were conducted at different soils with various irrigation amount. Image analysis was conducted to study the heterogeneous flow patterns and their relationships with the irrigation efficiency. Irrigation efficiency and its environmental effects were evaluated using various indictors, including application efficiency, deep percolation ratio, storage efficiency, and uniformity. Under the same irrigation condition, soil chemical distributions were more heterogeneous than soil water distributions. The distributions were mainly affected by soil texture, initial soil water content, and irrigation amount. Storage efficiency, irrigation uniformity, and deep percolation ratio increased with irrigation amount. Since the chemical distribution uniformity was lower than the water uniformity, the amount of chemical leaching increased sharply with decrease of irrigation uniformity, which resulted in high environmental risks of groundwater pollution.

关键词： irrigation efficiency chemical transport groundwater pollution

Effect of temperature and mating pair on tribological properties of DLC and GLC coatings under high pressure lubricated by MoDTC and ZDDP

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Friction 2021年第6期9卷 1390-1405页

作者： kang LIU jia-jie kang Guang-an ZHANG Zhi-bin LU Wen YUE School of Engineering and Technology China University of Geosciences(Beijing)Beijing 100083China Key Laboratory of Deep GeoDrilling Technology of Ministry of Natural Resources Beijing 100083China Zhengzhou Institute China University of Geosciences(Beijing)Zhengzhou 451283China State Key Laboratory of Solid Lubrication Lanzhou Institute of Chemical PhysicsChinese Academy of SciencesLanzhou 730000China

Diamond-like carbon(DLC)and graphite-like carbon(GLC)coatings have good prospects for improving the surface properties of engine ***,further understanding is needed on the effect of working conditions on tribological *** this study,GLC and two types of DLC coatings were deposited on GCr15 substrate for *** friction and wear properties of self-mated and steel-mated pairs were *** temperatures(25 and 90℃),three lubrication conditions(base oil,molybdenum dithiocarbamate(MoDTC)-containing oil,MoDTC+zinc dialkyldithiophosphate(ZDDP)-containing oil),and high Hertz contact stress(2.41 GPa)were applied in the *** results showed that high temperature promoted the effect of ZDDP on steel-mated pairs,but increased wear under base oil *** increased wear for steel-mated pairs lubricated by MoDTC-containing oil was due to abrasive wear probably caused by MoO_(3) andβ-FeMoO_(4).It was also found that in most cases,the tribological properties of self-mated pairs were better than those of steel-mated pairs.

关键词： diamond-like carbon(DLC) graphite-like carbon(GLC) mating pair temperature oil additives

Ultrastructural Changes in the Interaction Between Puccinia striiformis and Wheat Cultivar with Slow-Rusting Resistance

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Agricultural Sciences in China 2010年第1期9卷 64-70页

作者： jiaNG Xuan-li kang Zhen-sheng Department of Plant Protection Agricultural College Guizhou University Guiyang 550025 P.R.China Plant Protection College Northwest A&F University Yangling 712100 P.R.China

Ultrastructural changes in both pathogen and host cells in the interaction between Puccinia striiformis and wheat cultivar （Libellula） with slow-rusting resistance were observed by transmission electron microscopy. Observations revealed marked changes in ultrastructure of both pathogen and host cells. In the pathogen respect, there were many vesicles appeared in the intercellular hyphae and gradually fused into bigger vacuoles, a number of fat drops and electron-dense granules accumulated, mitochondria became swollen and some of them degraded into vesicles, and the plasmalemma of intercellular hyphae became dark. In the haustoria, the cytoplasm degraded gradually and developed a vacuole in the center, fat drops increased, the extrahaustorial matrix widened with a great amount of electron-dense fibrillar and granular materials, and most of the haustoria died with in conjunction with the disappearance of fat drops and other organelles. Structural defense of the host, including formation of cell wall apposition, collar and papilla, occurred in the host respect. Host resistance expression and cytological features occurring in the slow-rusting resistance were discussed.

关键词： wheat Puccinia striiformis ultrastructure slow-rusting resistance

Enantioselective chlorination of β-keto esters and amides catalyzed by chiral copper(Ⅱ) complexes of squaramide-linked bisoxazoline ligand

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Chinese Chemical Letters 2014年第11期25卷 1479-1484页

作者： sheng-jian jia Da-Ming Du School of Chemical Engineering and Environment Beijing Institute of Technology

Enantioselective chlorination of b-keto esters and amides catalyzed by squaramide-linked bisoxazoline ligand–Cu（OAc）2complexes was investigated. The corresponding chlorinated products were obtained in excellent yields with moderate enantioselectivities. The effect of solvent, temperature, Lewis acid, and ligand structure on the reaction is discussed. This was the first investigation of catalytic asymmetric achlorination of b-keto amides. This study has highlighted that a simple chiral squaramide–oxazoline with cheap Cu（OAc）2 H2 O complexes can catalyze this chlorination.

关键词： Asymmetric catalysis Bisoxazoline Squaramide Chlorination b-Keto esters

Factors influencing the performance of paintable carbon-based perovskite solar cells fabricated in ambient air

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Chinese Physics B 2018年第3期27卷 508-514页

作者： Wei-kang Xu Feng-Xiang Chen Gong-Hui Cao jia-Qi Wang Li-sheng Wang Department of Physics Science and Technology School of Science Wuhan University of Technology Wuhan 430070 China

To date, many efforts have been made to improve the performance of paintable carbon-based （PC-based） perovskite solar cells （PSCs）. Though great progress has been achieved, their power conversion efficiencies are still relatively low compared with hole-transport-materials-based PSCs. General research on influencing factors of performance in PC-based PSCs is still insufficient. In this work, PC-based PSCs were fabricated in ambient air and four groups of controlled experi- ments were performed in which the PbI2 layers were prepared with or without antisolvent extraction treatment. These four groups of experiments were designed to find out the effect of different influencing factors on PC-based PSCs performance, for example, PbI2 residual, the surface morphology of the perovskite film, the surface roughness of the perovskite film, and the contact status of the perovskite/carbon electrode interface. With a systematic analysis, we demonstrated that the contact status of the perovskite/carbon electrode interface played a vital role in PC-based PSCs, and a fiat, smooth perovskite surface could help to improve this contact status significantly. Besides, on the precondition of a poor contact interface, no PbI2 residual and a good surface morphology only brought limited benefits to the performances of PC-based PSCs.

关键词： influencing factors paintable carbon-based perovskite solar cells contact status

Some Comments on the Frame of Regge Phenomenology and the Glueball Production Mechanism

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Chinese Physics Letters 2000年第12期17卷 868-870页

作者： PENG Hong-An XU jia-sheng Department of Physics Peking UniversityBeijing 100871 China Center of Advance Science and Technology(World Laboratory) Beijing 100080

We enumerate the limitations in the frame of Regge phenomenology and demonstrate that it should be extended to cover the freedom of constituent gluon,We declare that glueballs are the bound states of constituent *** o... 详细信息

关键词： Regge limitations constituent

Identification of temperature anomaly RR Lyrae stars in LAMOST survey,misclassification and binarities

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Research in Astronomy and Astrophysics 2020年第6期20卷 239-252页

作者： Lin-jia Li sheng-Bang Qian jia Zhang jia-jia He Li-Ying Zhu Yunnan Observatories Chinese Academy of SciencesKunming 650216China Key laboratory of the structure and evolution of celestial objects Chinese Academy of SciencesKunming 650216China Center for Astronomical Mega-Science Chinese Academy of SciencesBeijing 100101China University of Chinese Academy of Sciences Beijing 100049China

RR Lyrae stars,a well-known type of pulsating variable stars,have been known about for more than a century.A large amount of photometric data on RR Lyrae stars has been accumulated by space-and ground-based sky surveys,but the spectral data are relatively ***,the LAMOST sky survey project provides an opportunity to view them from the point of view of *** collect the atmospheric parameters of 1685 RR Lyrae stars provided by the LAMOST catalog,and carry out research by using the reliable *** find that there is a clear correlation between their Teff and pulsation periods,which is consistent with the pulsation and evolution theories of RR Lyrae *** addition,we focus on those RR Lyrae stars with abnormal *** analyzing the data from several photometric surveys,we find that some of these temperature anomalies are misclassified variable stars(e.g.,eclipsing binaries,pulsating stars on main sequence),and some are RR Lyrae binary *** the latter,the temperatures of potential companions should be lower and their luminosities should not be neglected(e.g.,red giant stars).We obtain that the ratio of temperature anomaly stars to all the sample stars is 4%,which means that the impact on the further analysis(e.g.,kinematics analysis)is *** also present the catalogs of spectral anomaly RR Lyrae stars.

关键词： techniques spectroscopic-techniques photometric-stars fundamental parameters-stars variables RR Lyrae

Synthesis,Characterization of Polyethylene Ionomers and Their Antibacterial Properties

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Chinese Journal of Polymer Science 2024年第8期42卷 1077-1084页

作者： jia-jia Wu Fei Wang Peng-Qi Wan Li Pan Chun-sheng Xiao Zhe Ma Yue-sheng Li Tianjin Key Lab Composite&Functional Materials School of Materials Science and EngineeringTianjin UniversityTianjin 300350China Key Lab Polymer Ecomaterials Changchun Institute of Applied ChemistryChinese Academy of SciencesChangchun 130022China

Owing to its high production volume and wide range of application s,polyethylene has gained a great deal of attention,but its low surface energy and non-polar nature have limited its application in some important *** this study,ethylene/11-iodo-1-undecene copolymers were prepared and used as the intermediates to afford a series of imidazolium-based ionomers bearing methanesulfonate(CH_(3)SO_(3)^(-)),trifluoromethanesulfonate(CF_(3)SO_(3)^(-)),or bis(trifluoromethane)sulfonimide(Tf_(2)N^(-))*** tensile test results showed that the stress-at-break(7.8-25.6 MPa)and the elongation-at-break(445%-847%)of the ionomers could be adjusted by changing the counterion species and the ionic group *** importantly,the ionomers exhibited marvelous antibacterial activities against Staphylococcus aureus(***)and Escherichia coli(***).The ionomers bearing Tf_(2)N^(-)exhibited antibacterial activities>99%against both *** and *** when ionic content reached 9.1%.The imidazolium-based ionomers prepared in this work demonstrated excellent comprehensive properties,especially highefficient and broad-spectrum antibacterial ability,exhibiting the potential fo r the application as the antibacterial materials in packaging,medical,and other fields.

关键词： Polyethylene Ionomer Polymerization catalysis Imidazolium Antibacterial material

Closing the door to human immunodeficiency virus

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Protein & Cell 2013年第2期4卷 86-102页

作者： Yuanxi kang jia Guo Zhiwei Chen AIDS Institute and Department of Microbiology of Li Ka Shing Faculty of Medicine The University of Hong Kong21 Sassoon RoadPokfulamHong Kong SARChina Research Center for Infection and Immunity The University of Hong Kong21 Sassoon RoadPokfulamHong Kong SARChina

The pandemic of human immunodeficiency virus type one(HIV-1),the major etiologic agent of acquired immunodeficiency disease(AIDS),has led to over 33 million people living with the virus,among which 18 million are women and *** now,there is neither an effective vaccine nor a therapeutic cure despite over 30 years of *** the Thai RV144 vaccine trial has demonstrated an efficacy of 31.2%,an effective vaccine will likely rely on a break-through discovery of immunogens to elicit broadly reactive neutralizing antibodies,which may take years to ***,there is an urgency of exploring other prophylactic ***,antiretroviral treatment as prevention is an exciting area of pro-gress in HIV-1 *** effective,the im-plementation of such strategy faces great financial,political and social challenges in heavily affected re-gions such as developing countries where drug re-sistant viruses have already been found with growing *** latently infected cells for thera-peutic cure is another area of *** it is greatly difficult to eradicate HIV-1 after the establish-ment of viral latency,it is necessary to investigate strategies that may close the door to ***,we review studies on non-vaccine strategies in targeting viral entry,which may have critical implications for HIV-1 prevention.

关键词： HIV-1 entry inhibitor vaccine antiretrovi-ral antibody