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Preparation and characterization of 3-aminopropyl-triethoxysilane grafted montmorillonite and acid-activated montmorillonite

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Chinese Science Bulletin 2009年第2期54卷 265-271页

作者： SHEN Wei HE HongPing ZHU JianXi yuan Peng ma YueHong liang Xiaoliang Guangzhou Institute of Geochemistry Chinese Academy of Sciences Guangzhou 510640 China Graduate University of Chinese Academy of Sciences Beijing 100049 China

3-aminopropyltriethoxysilane grafted montmorillonites were synthesized with montmorillonite, acidactivated montmorillonites and 3-aminopropyltriethoxysilane in ethanol-water mixture. The resulting products were investigated using Fourier transform infrared (FTIR) spectroscopy, X-ray diffraction (XRD), thermogravimetric analysis (TG). XRD patterns demonstrated that silane was intercalated into the montmorillonite gallery, indicated by increasing basal spacings. These intercalated silanes probably adopt bilayer arrangement models within the montmorillonite and acid-activated montmorillonites interlayer spaces. TG and DTG curves indicate that acidification results in a decrease of the thermal stability of the resultant montmorillonites. Silane grafting leads to a surface property transformation of montmorillonite from hydrophilicity to lipophilicity and an increase of the thermal stability of the condensed silanes.

关键词：蒙脱石催化剂合成化学成分 3-氨基丙基三乙氧基硅烷

Recent progress on dense nuclear matter in skyrmion approaches

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Science China(Physics,Mechanics & Astronomy) 2017年第3期60卷 1-24页

作者： Yong liang ma mannque Rho Center of Theoretical Physics and College of Physics Jilin University Institut de Physique Th'eorique CEA Saclay

The Skyrme model provides a novel unified approach to nuclear physics. In this approach, single baryon, baryonic matter and medium-modified hadron properties are treated on the same footing. Intrinsic density dependence(IDD) reflecting the change of vacuum by compressed baryonic matter figures naturally in the approach. In this article, we review the recent progress on accessing dense nuclear matter by putting baryons treated as solitons, namely, skyrmions, on crystal lattice with accents on the implications in compact stars.

关键词： Skyrme model hidden symmetries skyrmion crystal holographic nucleon BPS nuclei compact stars

The entropy characters of point mutation

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Chinese Science Bulletin 2008年第19期53卷 3008-3015页

作者： ma GuoJi liang LiJing FAN YanHui WANG WenJuan DAI JiaQing yuan ZhiFa College of Science Northwest A&F University Yangling 712100 China Bioinformatics Center Northwest A&F University Yangling 712100 China College of Life Sciences Northwest A&F University Yangling 712100 China

The biological diversity, which depends on the genetic material DNA, is the foundation for a species to survive and evolve. The entropy is the best measurement of biological diversity. Based on the sin-gle-parameter and the two-parameter models, here we established some differential equations about the point mutation of a DNA sequence with finite length, as well as some functions describing the processes of the variation in quantities of 4 kinds of bases (A, T, G and C) in the DNA sequence. At the molecular level, we discussed the entropy characteristics of point mutation. The results proved that a species maintained its entropy and evolved in the direction of the increasing biological diversity. In order to testify the theoretical results, we did a series of computer simulations of random point muta- tion in matlab environment. The results were well consistent with the theoretical researches.

关键词：基因突变信息处理生物多样化实验研究

A novel lead-free Na_(0.5)Bi_(0.5)TiO_(3)-based ceramic with superior comprehensive energy storage and discharge properties for dielectric capacitor applications

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Journal of materiomics 2020年第4期6卷 743-750页

作者： Da Li Ying Lin Qibin yuan Miao Zhang liang ma Haibo Yang Shaanxi Key Laboratory of Green Preparation and Functionalization for Inorganic materials School of Materials Science and EngineeringShaanxi University of Science and TechnologyXi’an710021China School of Electronic Information&Artificial Intelligence Shaanxi University of Science and TechnologyXi’an710021China Xianyang Non-metallic Mineral R&D Institute Co. LtdXianyang712021China

Na_(0.5)Bi_(0.5)TiO_(3)(NBT)-based ceramics have been widely used as dielectric materials for energy storage capacitors because of their environmental friendliness and excellent ferroelectric ***,their energy storage performance still needs to be further improved to satisfy the increasing ***,we report a novel 0.90(Na_(0.5)Bi_(0.5))0.7Sr_(0.3)TiO_(3-0.10)Bi(Ni_(0.5)Sn_(0.5))O_(3)(0.90NBST-0.10BNS)ceramic with significantly improved energy density(5.0 J cm3),enhanced recoverable energy density(4.18 J cm^(3))and high energy efficiency(83.64%)through the incorporation of Bi(Ni0.5Sn0.5)O3(BNS),due to the increased breakdown strength and the relaxation ferroelectric(RFE)*** first-order reversal curve(FORC)measurements confirm that the addition of BNS improves RFE properties by breaking the order of long-range *** 0.90NBST-0.10BNS ceramic also possesses an outstanding temperature and frequency stability of energy storage properties in the range of 20C e140C and 1 Hze100 Hz,*** importantly,the discharge properties characterized by a preeminent power density(36.19 MW cm^(3)),transient energy release times(144.2 ns),and high discharge energy density(1.16 J cm3)also synchronously observed in 0.90NBST-0.10BNS *** results show that the 0.90NBST-0.10BNS ceramic with outstanding comprehensive performances is a promising energy storage ceramic candidate for capacitors in high power systems.

关键词： Na_(0.5)Bi_(0.5)TiO_(3) Ferroelectric properties Energy density Temperature stability Power density

magnetic two-dimensional layered crystals meet with ferromagnetic semiconductors

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Infomat 2020年第4期2卷 639-655页

作者： Yilv Guo Bing Wang Xiwen Zhang Shijun yuan liang ma Jinlan Wang School of Physics Southeast UniversityNanjingChina

The existence of intrinsic ferromagnetic semiconductors(FMSs)in twodimensional(2D)materials has been a long-term concern and *** breakthroughs in the 2D FMSs,such as CrGeTe3 and CrX3(X=Cl,Br,I)from bulk down to monolayer,have stimulated intensive researches on new physical phenomena and creative *** minireview mainly summarizes recent progress of 2D intrinsic FMSs in theoretical side,and focuses on the ongoing strategies proposed to enhance ferromagnetism,involving the mechanisms of magnetic exchange interaction and the significance of magnetic ***,spin-related multifunctionality with ultrathin FMSs and their van de Waals heterostructures in magnetoelectric,valleytronic,and nondissipative electronic technology are introduced,as well as the current challenges and the prospects in this field are discussed.

关键词： ferromagnetic semiconductors first-principles methods two-dimensional materials

History of and suggestions for China’s biosafety legislation

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Journal of Biosafety and Biosecurity 2019年第2期1卷 134-139页

作者： liang Huigang Xiang Xiaowei ma Haixia yuan Zhiming Wuhan Documentation and Information Center Chinese Academy of SciencesWuhan CityChina Huazhong University of Science and Technology Wuhan CityChina Wuhan Institute of Virology CASWuhan CityChina

Biosafety has attracted an unprecedented amount of attention from the global community as an important element in national *** biosafety issues are related to laws and therefore must be regulated accordingly.A preliminary biosafety legislation system based on and suitable for China’s actual conditions has been *** provisions of numerous laws have provided legislative tools to manage biosafety *** State Council and relevant ministries have also exercised their respective functions and drafted codes and regulations concerning biosafety *** laws and regulations play important roles,but our nation still lacks a law solely dedicated to biosafety regulation,and the supervisory system is *** remedy this situation,relevant biotechnologies must be developed,issues related to biosafety must be thoroughly examined,and the best practices of other nations should be introduced,all of which will improve biosafety legislation in China.

关键词： Biosafety legislation in China History Trend

Images of Azurin Protein Studied by AFM

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Chemical Research in Chinese Universities 2004年第4期20卷 437-439页

作者： WANG Nan WANG yuan-liang Biomedical Engineering Department Chongqing UniversityChongqing 400044P.R.China Inorganic Chemistry Department South Parks RoadUniversity of OxfordOX13QRUK

Azurins, a wild type and a genetically mutant K27 altered one, were immobilized on annealed gold surface and investigated by means of atomic force microscopy. It was found that the surface coverage and height distribution of the adsorbed protein molecules are different from each other, which is possibly the result of the different orientation on the surface. It is believed that the wild type azurin is connected to gold surface by the disulphide bridge; while the mutant, K27C, might be through the thiol groups of the cysteine residues on their surface.

关键词： Atomic force microscopy Protein Azurin Topography

Natural and human-induced decline and spatio-temporal differentiation of terrestrial water storage over the Lancang-Mekong River Basin

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Journal of Geographical Sciences 2025年第1期 112-138页

作者： CHEN Junxu WANG yuan ZHAO Zhifang FAN Yunjiang LUO Xiaochuan YI Lu FENG Siqi YANG liang Emlyn Yunnan Key Laboratory of Soil Erosion Prevention and Green Development Yunnan University International Joint Research Center for Karstology Yunnan University School of Engineering Westlake University Department of Geography Ludwig Maximilian University of Munich (LMU)

Due to water conflicts and allocation in the Lancang-Mekong River Basin(LMRB), the spatio-temporal differentiation of total water resources and the natural-human influence need to be clarified. This work investigated LMRB's terrestrial water storage anomaly(TWSA) and its spatio-temporal dynamics during 2002–2020. Considering the effects of natural factors and human activities, the respective contributions of climate variability and human activities to terrestrial water storage change(TWSC) were separated. Results showed that:(1) LMRB's TWSA decreased by 0.3158 cm/a.(2) TWSA showed a gradual increase in distribution from southwest of MRB to middle LMRB and from northeast of LRB to middle LMRB. TWSA positively changed in Myanmar while slightly changed in Laos and China. It negatively changed in Vietnam, Thailand and Cambodia.(3) TWSA components decreased in a descending order of soil moisture, groundwater and precipitation.(4) Natural factors had a substantial and spatial differentiated influence on TWSA over the LMRB.(5) Climate variability contributed 79% of TWSC in the LMRB while human activities contributed 21% with an increasing impact after 2008. The TWSC of upstream basin countries was found to be controlled by climate variability while Vietnam and Cambodia's TWSC has been controlled by human activities since 2012.

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Negative corrections to black hole entropy from string theory

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Science China(Physics,Mechanics & Astronomy) 2023年第12期66卷 71-76页

作者： liang ma Yi Pang Hong Lu Center for Joint Quantum Studies and Department of Physics School of ScienceTianjin UniversityTianjin 300350China Joint School of National University of Singapore and Tianjin University International Campus of Tianjin UniversityFuzhou 350207China

We report for the first time that in heterotic string compactified on 4-torus or equivalently IIA string compactified on K3,the leading α′corrections to the rotating black string entropy at fixed conserved charges can be *** further implies that the correction to the mass of extremal rotating string is positive,opposite to the standard expectation from the weak gravity *** result suggests that the validity of positivity of entropy shift due to higher order operators depends on other factors omitted previously in the effective field theory analysis.

关键词： supergravities higher-derivative corrections effective theories black holes quantum gravity string theory