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Controllable synthesis and tunable photocatalytic activity of TiO2 nanowires via alcohol-thermal method

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Rare Metals 2019年第5期38卷 390-396页

作者： Zheng-xia Xu An-qi Wang Yong-Fa Zhu School of Civil Engineering and Mechanics Yanshan UniversityQinhuangdao 066004China Department of Chemistry Tsinghua UniversityBeijing 100084China

Titania nanowires(TiO2-NW)with tunable aspect ratios and morphologies were directly synthesized using a simple alcohol-thermal ***,ethanol and acetic acid were used as solvents and lithium ion was used as the capping agent to promote the conversion of titanium butoxide into *** morphologies and crystal phases of TiO2-NW were determined by the molar ratio of solvents and the content(mol%)of lithium *** band gap of TiO2-NW with pure anatase phase is slightly bigger than that of TiO2-NW with a mixture of anatase and rutile *** TiO2-NW could achieve effective decolorization of methyl blue(the decolorization rate is over 95%)after 35-min ultraviolet(UV)irradiation.

关键词： Nanowires TiO2 Photocatalysis Degradation Photocurrent

On the Longest Length of Consecutive Integers

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Acta Mathematica Sinica,English Series 2011年第2期27卷 329-338页

作者： Min zhi ZHAO qi-Man SHAO Department of Mathematics Zhejiang University Hangzhou 310027 P. R. China Department of Mathematics Hong Kong University of Science and Technology Clear Water Bay Kowloon Hong Kong P. R. China

Choose m numbers from the set {1,2,... ,n} at random without replacement. In this paper we first establish the limiting distribution of the longest length of consecutive integers and then apply the result to test rand... 详细信息

关键词： Sampling without replacement consecutive integers limit distribution test of randomness

Weak Poincaré Inequalities,Decay of Markov Semigroups and Concentration of Measures

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Acta Mathematica Sinica,English Series 2005年第4期21卷 937-942页

作者： Feng Yu WANG qi zhi ZHANG School of Mathematical Sciences Beijing Normal University Beijing 100875 P. R. China

For a reasonable class of weak Poincaré inequalities, the decay of the corresponding Markov semigroups obtained earlier by Rockner and the first named author is improved by removing an extra L^2-norm. Next, a concentration estimate of the reference measure is presented for the weak Poincaré inequality, which is sharp as illustrated by some examples of one-dimensional diffusion processes.

关键词： Weak Poincaré inequality Markov semigroup Concentration of measures

Weak Cartan-type Second Main Theorem for Holomorphic Curves

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Acta Mathematica Sinica,English Series 2008年第3期24卷 455-462页

作者： qi Ming YAN zhi Hua CHEN Department of Mathematics Tongji University Shanghai 200092 P. R. China

In this paper, a weak Cartan-type second theorem for holomorphic curve f ： C→P^n（C） intersecting hypersurfaces Dj, 1≤j≤q, in P^n（C） in general position with degree dj is given as follows： For every ε〉0, there exists a positive integer M such that ｜｜（q - （n ＋ 1） ε）Tf（r）≤∑j^q=1 1/dj Nf^M（r,Dj）＋o（Tf（r））, where ＂｜｜＂ means the estimate holds for all large r outside a set of finite Lebesgue measure.

关键词： holomorphic curve Nevanlinna Theory second main theorem hypersurface

Changes in fungal community and diversity in strawberry rhizosphere soil after 12 years in the greenhouse

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Journal of Integrative Agriculture 2019年第3期18卷 677-687页

作者： LI Wei-hua LIU qi-zhi College of Plant Protection China Agricultural University

Soil fungi play a very important role in the soil ecological environment. In agricultural production, long-term monoculture and continuous cropping lead to changes in fungal community diversity. However, the effects of long-term monoculture and continuous cropping on strawberry plant health and fungal community diversity have not been elucidated. In this study, using high-throughput sequencing(HTS), we compared the fungal community and diversity of strawberry rhizosphere soil after various durations of continuous cropping(0, 2, 4, 6, 8, 10 and 12 years). The results showed that soil fungal diversity increased with consecutive cropping years. Specifically, the soil-borne disease pathogens Fusarium and Guehomyces were significantly increased after strawberry continuous cropping, and the abundance of nematicidal(Arthrobotrys) fungi decreased from the fourth year of continuous cropping. The results of correlation analysis suggest that these three genera might be key fungi that contribute to the changes in soil properties that occur during continuous cropping. In addition, physicochemical property analysis showed that the soil nutrient content began to decline after the fourth year of continuous cropping. Spearman's correlation analysis showed that soil pH, available potassium(AK) and ammonium nitrogen(NH_4^+-N) were the most important edaphic factors leading to contrasting beneficial and pathogenic associations across consecutive strawberry cropping systems.

关键词： fungal community soil-borne disease replanted strawberry rhizosphere soil agricultural soil ecology

Autophagy in plants: Physiological roles and post-translational regulation

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Journal of Integrative Plant Biology 2021年第1期63卷 161-179页

作者： Hua qi Fan-Nv xia Shi xiao State Key Laboratory of Biocontrol Guangdong Provincial Key Laboratory of Plant ResourcesSchool of Life SciencesSun Yat-sen UniversityGuangzhou 510275China

In eukaryotes, autophagy helps maintain cellular homeostasis by degrading and recycling cytoplasmic materials via a tightly regulated *** the past few decades, significant progress has been made towards understanding the physiological functions and molecular regulation of autophagy in plant cells. Increasing evidence indicates that autophagy is essential for plant responses to several developmental and environmental cues, functioning in diverse processes such as senescence, male fertility, root meristem maintenance, responses to nutrient starvation,and biotic and abiotic stress. Recent studies have demonstrated that, similar to nonplant systems,the modulation of core proteins in the plant autophagy machinery by posttranslational modifications such as phosphorylation, ubiquitination,lipidation, S-sulfhydration, S-nitrosylation, and acetylation is widely involved in the initiation and progression of autophagy. Here, we provide an overview of the physiological roles and posttranslational regulation of autophagy in plants.

关键词： autophagy physiological roles post-translational regulation

Prevalence of coronary artery ectasia in older adults and the relationship with epicardial fat volume by cardiac computed tomography angiography

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Journal of Geriatric Cardiology 2013年第1期10卷 10-15页

作者： Jun-Jie Yang xia Yang zhi-Ye Chen qi Wang Bai He Luo-Shan Du Yun-Dai Chen Department of Cardiology Chinese PLA General Hospital 28 Fuxing Road Beijing 100853 China Department of Radiology Chinese PLA General Hospital 28 Fuxing Road Beijing 100853 China

Objective Coronary artery ectasia (CAE) refers to abnormal dilation of coronary artery segments to 1.5 times of adjacent normal ones. Epicardial fat is associated with cardiovascular risk factors. The relationship between CAE and epicardial fat has not yet been investigated. This study aimed to assess the relationship between CAE and epicardial fat volume (EFV) in older people by dual-source computed tomography coronary angiography (CTCA). Methods We prospectively enrolled 1400 older adults who were scheduled for dual-source CTCA. Under reconstruction protocols, patients with abnormal segments 1.5 times larger than the adjacent segments were accepted as CAE. EFV was measured by semi-automated software. Traditional risk factors in CAE patients, as well as the extent of EFV, were analyzed and compared to non-CAE group. Results A total of 885 male and 515 female older patients were enrolled. CAE was identified by univariable analysis in 131 patients and significantly correlated to hypertension, smoking, hyperlipidemia, prior percutaneous coronary intervention and ascending aorta aneurysm. EFV was shown to be significantly higher inCAE patients than patients without ectasia. Inmultivariable analyses, EFV (P = 0.018), hypertension (P < 0.001) and hyperlipidemia (P < 0.001) were significantly correlated to CAE. There was a significant negative correlation between EFV and Markis classification. Conclusions CAE can be reliably recognized by dual-source CTCA. Epicardial fatmight play a role in etiopathogenesis and progression of CAE, providing a newtarget for treating ectasia.

关键词： Cardiac computed tomography angiography Coronary artery ectasia Epicardial fat

Liquid Crystalline Polymers

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Chinese Journal of Polymer Science 2022年第2期40卷 121-123页

作者： zhi-Hao Shen qi-Feng Zhou Peking University

History of Liquid Crystalline PolymersThe liquid crystalline(LC)state was first observed by Austrian botanist and chemist *** more than a century ago,and it was then confirmed in 1888 by German physicist *** who named such a state of matter as"liquid crystal"in *** low molecular mass(LMM)liquid crystals were successfully used in LC displays(LCDs),the development of LC polymers(LCPs)followed an independent ***,LCPs are prepared with the incorporation of mesogenic groups that are responsible for the formation of LC mesophases,such as rod-like(calamitic)and discotic ones,into polymer *** on where the mesogens are attached,traditionally there are three major categories of ***-chain LCPs(MCLCPs)have mesogens in the polymer backbone,while mesogens of side-chain LCPs(SCLCPs)are incorporated as side groups in a polymer with a relatively flexible main *** main-chain/side-chain combined LCPs(MCSCLCPs),mesogens are in both the backbone and side *** classes of LCPs include mesogenjacketed LCPs(MJLCPs),dendronized LCPs,and LC networks(LCNs).

关键词： backbone chains Crystalline

Analysis of detection capabilities of LEO reconnaissance satellite constellation based on coverage performance

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Journal of Systems Engineering and Electronics 2018年第1期29卷 98-104页

作者： MENG Shaofei SHU Jiansheng YANG qi xia Wei Graduate School Rocket Force University of Engineering

In the design problem of low earth orbit(LEO) reconnaissance satellite constellation, optimization of coverage performance is the design goal in most current methods. However,in the using process, the user only concerns with the detection capabilities rather than coverage performance. To establish the relationship between these two aspects, the reconnaissance processes of normal stochastic targets are considered and the mathematic models of detection processes are built. The indicators of coverage performance are used to evaluate the detection probability and expectation of detection time delay, which are important factors in reconnaissance constellation estimation viewed from military intelligence discipline. The conclusions confirmed by the final simulation will be useful in LEO reconnaissance constellation design, optimization and evaluation.

关键词： low earth orbit(LEO) reconnaissance satellite constellation detection capability Monte Carlo experiment