检索结果-南通市图书馆

A high resolution lithospheric magnetic field model over China

在线全文

学校读者我要写书评

暂无评论

Science China Earth Sciences 2013年第10期56卷 1759-1768页

作者： ou JiaMing DU AiMin E.THBAULT XU WenYao tian XiaoBo ZHANG TieLong Institute of Geology and Geophysics Chinese Academy of Sciences Graduate University of Chinese Academy of Sciences Equipe de Géomagnétisme Institut de Physique du Globe de ParisSorbonne 4 Paris CitéINSU/CNRS1 rue Jussieu75005 ParisFrance Space Research Institute Austrian Academy of Sciences

CHAMP satellite data and ground-based magnetic observations are used and combined to map the lithospheric magnetic field over China by means of the revised spherical cap harmonic analysis(R-SHCA)modeling *** magnetic field is described to a spatial resolution of 150 km at the mean Earth’s radius,which represents a good compromise between the resolutions afforded by surface and satellite *** compare the magnetic anomalies modeled at the regional scale with composite regions containing large-scale of tectonic *** regions,including the Tarim Basin and the Tibetan Plateau,are correlated with regional magnetic anomalies at satellite altitude but contain a significant number of small-scale and complex magnetic structures at the mean Earth’s *** magnetic anomalies are globally consistent with the known geological features in China but also offer a way to delineate the contours of the geological blocks and to discuss the connection between magnetic anomalies and the heat flow distribution in this region.

关键词： lithospheric magnetic field revised spherical harmonic cap analysis CHAMP satellite data

Berberine enhances antidiabetic effects and attenuates untoward effects of canagliflozin in streptozotocin-induced diabetic mice

在线全文

学校读者我要写书评

暂无评论

Chinese Journal of Natural Medicines 2016年第7期14卷 518-526页

作者： tian Cai-Ming JIANG Xin ouYANG Xiao-Xi ZHANG Ya-ou XIE Wei-Dong Department of chemistry Tsinghua University Shenzhen Key Lab of Health Science and Technology Division of Life Science & Health Graduate School at ShenzhenTsinghua University School of Life Sciences Tsinghua University

The present study aimed at determining whether berberine can enhance the antidiabetic effects and alleviate the adverse effects of canagliflozin in diabetes mellitus. Streptozotocin-induced diabetic mice were introduced, and the combined effects of berberine and canagliflozin on glucose metabolism and kidney functions were investigated. our results showed that berberine combined with canagliflozin(BC) increased reduction of fasting and postprandial blood glucose, diet, and water intake compared with berberine or canagliflozin alone. Interestingly, BC showed greater decrease in blood urea nitrogen and creatinine levels and lower total urine glucose excretion than canagliflozin alone. In addition, BC showed increased phosphorylated 5' AMP-activated protein kinase(p AMPK) expression and decreased tumor necrosis factor alpha(TNFα) levels in kidneys, compared with berberine or canagliflozin alone. These results indicated that BC was a stronger antidiabetic than berberine or canagliflozin alone with less negative side effects on the kidneys in the diabetic mice. The antidiabetic effect was likely to be mediated by synergically promoting the expression of p AMPK and reducing the expression of TNFα in kidneys. The present study represented the first report that canagliflozin combined with berberine was a promising treatment for diabetes mellitus. The exact underlying mechanisms of action should be investigated in future studies.

关键词： Canagliflozin Berberine Diabetes mellitus AMP-activated protein kinase Sodium-glucose cotransporter-2

Petroleum substitution, greenhouse gas emissions reduction and environmental benefits from the development of natural gas vehicles in China

在线全文

学校读者我要写书评

暂无评论

Petroleum Science 2018年第3期15卷 644-656页

作者： Jie-Hui Yuan Sheng Zhou tian-Duo Peng Ge-Hua Wang Xun-Min ou Institute of Energy Environment and Economy Tsinghua University China Automotive Energy Research Centre Tsinghua University

This study develops a bottom-up model to quantitatively assess the comprehensive effects of replacing traditional petroleum-powered vehicles with natural gas vehicles（NGVs） in China based on an investigation of the direct energy consumption and critical air pollutant（CAP） emission intensity, life-cycle energy use and greenhouse gas（GHG） emission intensity of NGV fleets. The results indicate that, on average, there are no net energy savings from replacing a traditional fuel vehicle with an NGV. Interestingly, an NGV results in significant reductions in direct CAP and life-cycle GHG emissions compared to those of a traditional fuel vehicle, ranging from 61% to 76% and 12% to 29%, respectively. Due to the increasing use of natural gas as a vehicle fuel in China（i.e. approximately 28.2 billion cubic metres of natural gas in2015）, the total petroleum substituted with natural gas was approximately 23.8 million tonnes（Mt）, which generated a GHG emission reduction of 16.9 Mt of CO2 equivalent and a CAP emission reduction of 1.8 Mt in 2015. Given the significant contribution of NGVs, growing the NGV population in 2020 will further increase the petroleum substitution benefits and CAP and GHG emission reduction benefits by approximately 42.5 Mt of petroleum-based fuel, 3.1 Mt of CAPs and 28.0 Mt of GHGs. By 2030, these benefits will reach 81.5 Mt of traditional petroleum fuel, 5.6 Mt of CAPs and 50.5 Mt of GHGs, respectively.

关键词： Natural gas vehicles Energy use Greenhouse gases Critical air pollutants China Life-cycle analysis

The role of apoptosis in Caenorhabditis elegans neuronal differentiation

在线全文

学校读者我要写书评

暂无评论

Science China(Life Sciences) 2015年第11期58卷 1163-1166页

作者： WU Kai Da tian Dong ZHU ZhiWen CHAI YongPing ou GuangShuo Tsinghua-Peking Center for Life Sciences School of Life Sciences Tsinghua University The High School Affiliated to Renmin University

Dear Editor,Neuronal apoptosis is considered to be essential for brain development and neurodegenerative disorders and has been a major focus in cell biological and neuroscientific studies since its first recognition a century ago [1]. Remarkable progress has been made in defining the molecular and cel- lular pathways underlying neuronal apoptosis during the past decade [2], however, it remains relatively unclear about the physiological functions of apoptosis in neural develop- ment. The neurotrophin hypothesis proposes that immature neurons compete for trophic factors that are derived from target neurons in limited supply and that only neurons that successfully establish synaptic connections with their tar- gets would receive trophic support to survive [3].

关键词：神经细胞分化细胞凋亡秀丽隐杆线虫神经营养因子神经退行性疾病神经元细胞生物学科学研究

A GNSS Space-time Anti-jamming Algorithm Based on Convex optimization

在线全文

学校读者我要写书评

暂无评论

A GNSS Space-time Anti-jamming Algorithm Based on Convex opt...

Photophysical and photosensitive properties of Elsinochrome A

第五届中国卫星导航学术年会

作者： Wu Shunxiao Huang Yangbo tian Feng ou gang College of Electronic Science and Engineering National University of Defense Technology

ISBN: (纸本)9783642547362

Traditional space-time adaptive processing algorithm can not well balance the demands between canceling jams and beam-forming. Aimed at this problem, A new algorithm based on convex optimization and multiple objectives programming is proposed for the designing of space-time filter. Two object functions are defined, and are combined via a object weight coefficient to form a single optimization goal. The relationship between the object weight coefficient and the optimization results is analyzed, and then proposed the criterion for judge the rationality of the object weight coefficient. The method for finding the optimal object weight coefficient is then developed. Results of computer simulation show that: the new method can form wide band main beam for useful signal direction under both strong and weak jams with a more low inserting loss compared with PI method;it overcomes the shortcomings of MSINR method that pass band of equivalent filter for useful signal direction will get narrower when the taps increase;especially when the signal and narrow-band jams come from the same direction the new method also performs well.

关键词： STAP beam-forming Convex Optimization MOP

来源： cnki会议评论

在线全文

cnki会议

学校读者我要写书评

暂无评论

Chinese Science Bulletin 2006年第9期51卷 1050-1054页

作者： LI Cong HE Yanping ou Lingcheng tian Maojun YAO Zhikun GUO Mengbi Center for Advanced Studies of Medicinal and Organic Chemistry Chemical and Material Engineering Institute of Yunnan UniversityKunming 650091 China

In this paper, the photophysical and photosensitive properties of Elsinochrome A (EA), another member of perylenequinone photosensitizers derived via artificially biological synthesis, were stud- ied by taking hypocrellin A (HA) and hypocrellin B (HB) as the references. It was found that the quantum yield of singlet oxygen produced via the photosensi- tization of EA was 0.98 with HB (0.84) as a reference. Furthermore, the semiquinone anion could be pro- duced via photosensitization of EA in oxygen-free solution. Besides, taking advantage of nanosecond time-resolved spectral technique, the transient triplet absorption spectra and the lifetime of EA in cyclo- hexane were determined by the use of the ground- state depletion method.

关键词：荧光光谱感光性能单态氧吸收光谱半醌自由基负离子光敏剂

Micromorphology and physicochemical properties of hydrophobic blasting dust in iron mines

在线全文

学校读者我要写书评

暂无评论

International Journal of Minerals,Metallurgy and Materials 2019年第6期26卷 665-672页

作者： Jian-guo Liu Long-zhe Jin Jia-ying Wang Sheng-nan ou Jing-zhong Guo tian-yang Wang School of Civil and Resource Engineering University of Science and Technology BeijingBeijing 100083China Key Laboratory of High-Efficient Mining and Safety of Metal Mines of the Ministry of Education University of Science and Technology BeijingBeijing 100083China Mine Emergency Technology Research Center University of Science and Technology BeijingBeijing 100083China College of Safety Engineering North China Institute of Science and TechnologyYanjiao 101601China

The micromorphology and physicochemical properties of hydrophobic blasting dust(HBD)from an iron mine were comprehensively analyzed by laser particle size analysis(LPSA),scanning electron microscopy(SEM),X-ray diffraction(XRD),and X-ray photoelectron spectroscopy(XPS).The results show that the HBD particles can be classified into three types based on their particle size(PS):larger particles(PS>10μm),medium particles(1μm≤PS≤10μm),and nanoparticles(PSounds of HBD were determined by XRD and XPS,*** adipate(C6H16N2O4)was the only organic compound in the body of HBD,but its mass fraction was only 13.4%.However,the content of organic C on the surface of HBD was 85.35%.This study demonstrated that the small-particle size and large amount of organic matter on the surface of HBD are the main reasons for its hydrophobicity,which can provide important guidance for controlling respirable dust in iron mines.

关键词： iron mine dust respirable dust hydrophobic blasting dust microstructure physicochemical properties particle size

Dynamical-Symmetry Breaking, Mechanism and Characterization Behaviour

在线全文

学校读者我要写书评

暂无评论

Chinese Physics Letters 2001年第5期18卷 625-627页

作者： XU Gong-ou XU Ming-Jie XING Yong-Zhong YANG Ya-tian Department of Physics Nanjing UniversityNanjing 210093 Department of Geoscience Nanjing UniversityNanjing 210093 Center of Theoretical Nuclear Physics National Laboratory of Heavy-Ion AcceleratorLanzhou 730000 Institute of Theoretical Physics Chinese Academy of SciencesBeijing 10008 Department of Physics Fujian Normal UniversityFuzhou 350007 Department of Physics Tianshui Normal CollegeTianshui 741000

The integrability of quantum systems is charactized by the algebraic notion of dynamical symmetry,hence the nonintegrability of quantum systems should be discussed topologically in reference to corresponding integrable ones.A topological approach is *** topological map in general is shown to be constituted of the piecewise diffeomorphic maps interrupted by sudden nondiffeomorphic maps and thus has the similar typical feature of stretching-folding stretching......as the Smale horse-shoe map.

关键词： topological stretching integrable

Synthesis and Crystal Structure of a Two-dimensional Cadmium(Ⅱ) Coordination Polymer:[Cd(AIP)(Bpy)]_n·nBpy(H_2AIP=5-Aminoisophthalic Acid, Bpy=2,2′-Bipyridyl)

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Chinese Journal of Structural Chemistry 2008年第2期27卷 159-162页

作者： ou Yang-Jun MA Cheng-Bing CHEN Hui WANG Hui-Sheng CHEN Chang-Neng LIU Qiu-tian State Key Laboratory of Structural Chemistry Fujian Institute of Research on the Structure of Matter The Chinese Academy of Sciences Fuzhou Fujian 350002 China

A two-dimensional coordination polymer, [Cd（AIP）（Bpy）]***, was hydrothermally synthesized by the reaction of hydrate cadmium acetate with 5-aminoisophthalic acid, lithium hydroxide, vanadiumpentoxide, sodium chloride and 2,2′-bipyridyl in water solution. It crystallizes in orthorhombic, space group C222 1, absolute structure parameter 0.00（7）, with a = 15.336（4）, b = 22.390（6）, c = 14.257（3）A, V = 4896（2）/~3, C28H21CdNsO4, Mr = 603.90, Z = 8, F（000） = 2432, Dc = 1.639 g/cm^3, μ = 0.939 mm^-1, T= 298（2） K, S = 1.001, R = 0.0296 and wR = 0.0813 for 5522 observed reflections （I 〉 2a（/））. In the title complex, each 5-aminoisophthalate ligand bridges three cadmium（Ⅱ） ions to form a two-dimensional layer structure.

关键词： synthesis crystal structure cadmium complex 5-aminoisophthalic acid