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Facile Synthesis of C3N4/Ag Composite Nanosheets as SERS Substrate for Monitoring the Catalytic Degradation of Methylene Blue

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Chemical Research in Chinese Universities 2018年第2期34卷 290-295页

作者： BU Tianjia ma xiaowei ZHAO Bing SONG Wei State Key Laboratory of Supramolecular Structure and materials Jilin University Changchun 130012 P. R. China

The C3N4/Ag composite nanosheets were facilely prepared via an in sire reduction process and Ag nanoparticles were well dispersed on the surface of C3N4 nanosheets. The unique two-dimensional structtlre and strong interactions between C3N4 nanosheets and Ag nanoparticles contributed the good surthce-enhanced Raman scattering（SERS） property due to the electromagnetic field enhancement. In addition, the as-prepared CaN4/Ag composite nanosheets could be used as catalysts or photocatalyst for the degradation of methylene blue（MB） in the presence of NaBH4 or under visible light. Therefore, a facile SERS monitoring of the catalytic and photocatalytic degradation process of MB and the determination of the reaction kinetics were developed.

关键词： C3N4 nanosheets Ag nanoparticles Composite Surface-enhanced Raman scattering Catalytic and photo-catalytic degradation

N-Heterocyclic Carbenes Catalyzed Phospho-Aldol Reaction of Aldehydes

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Chinese Journal of Chemistry 2013年第12期31卷 1573-1576页

作者： Lin He Zhihua Cai xiaowei ma Guangfen Du Key Laboratory for Green Processing of Chemical Engineering of Xinjiang Bingtuan and School of Chemistry and Chemical Engineering Shihezi University Xinjiang 832000 China

An efficient phospho-aldol reaction of aldehydes catalyzed by N-heterocyclic carbenes （NHCs） has been developed. With 10 mol% stable NHC 1,3-bis（2,6-diisopropylphenyl）imidazol-2-ylidene, various aldehydes reacted with dialkylphosphites smoothly to provide a-hydroxy phosphonates in 59%--99% yield. In this process, NHC was assumed to function as a carbon-centered bronsted base.

关键词： N-heterocyclic carbenes phosphite aldehyde phospho-aldol reaction a-hydroxy phosphonate

Investigating spatio-temporal characteristics and influencing factors for green energy consumption in China

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Geoscience Frontiers 2024年第3期15卷 221-236页

作者： xiaowei ma Shimei Weng Jun Zhao Huiling Liu Hongyun Huang School of Finance Anhui University of Finance and EconomicsBengbu 233030PR China Hefei Advanced Research Institute Anhui University of Finance and EconomicsHefei 230041PR China School of mathematics and Statistics Fujian Normal UniversityFuzhou 350117PR China School of Economics and management Beijing University of Chemical TechnologyBeijing 100029PR China School of Economics Hefei University of TechnologyHefei 230601PR China Qingdao Institute of Humanities and Social Sciences Shandong UniversityQingdao 266237PR China Center for Yellow River Ecosystem Products Shandong UniversityQingdao 266237PR China

The green transformation of energy consumption is beneficial for promoting green development in *** study constructed a green energy consumption evaluation index system and measured the green energy consumption levels in 30 provinces of China from 2000 to 2019 using the fuzzy comprehensive evaluation *** study further employed the spatial Durbin model to examine influencing factors and spillover effects of green energy *** results showed that,temporally,China’s green energy consumption levels had a fluctuating upward ***,spatially,the overall levels of green energy consumption in China showed apparent characteristics of“high in the west and low in the east”.In terms of influencing factors,environmental regulations played an important role in promoting green energy consumption in the region,while economic development,opening up,and industrial structure had considerably inhibiting ***,economic development,opening up,and industrial structure of neighboring regions showed marked positive spillover effects,while urbanization level and technological innovation showed substantial negative spillover *** regional heterogeneity test results showed that environmental regulation and industrial structure rationalization were the important factors for promoting green energy consumption in the eastern region,environmental regulation played an important driving role in the central region,and opening to the outside world and technological innovation helped improve the level of green energy consumption in the western region.

关键词： Energy green consumption Spatial and temporal characteristics Influencing factors Spatial Durbin model Regional heterogeneity

An improved ground motion intensity measure for super high-rise buildings

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Science China(Technological Sciences) 2013年第6期56卷 1525-1533页

作者： LU Xiao YE LiePing LU XinZheng LI MengKe ma xiaowei Department of Civil Engineering Tsinghua University

Ground motion intensity measure (IM) is an important part in performance-based seismic design. A reasonable and efficient IM can make the prediction of the structural seismic responses more accurate. Therefore, a more reasonable IM for super high-rise buildings is proposed in this paper. This IM takes into account the significant characteristic that higher-order vibration modes play important roles in the seismic response of super high-rise buildings, as well as the advantages of some existing IMs. The key parameter of the proposed IM is calibrated using a series of time-history analyses. The collapse simulations of two super high-rise buildings are used to discuss the suitability of the proposed IM and some other existing IMs. The results indicate that the proposed IM yields a smaller coefficient of variation for the critical collapse status than other existing IMs and performs well in reflecting the contribution of higher-order vibration modes to the structural response. Hence, the proposed IM is more applicable to seismic design for super high-rise buildings than other IMs.

关键词： ground motion intensity measure super high-rise building time-history analysis collapse analysis

miR-137, a new target for post-stroke depression?

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Neural Regeneration Research 2013年第26期8卷 2441-2448页

作者： Lixia Zhao Huazi Li Ruiyou Guo Teng ma Rongyao Hou xiaowei ma Yifeng Du Department of Neurology Shandong Provincial Hospital Department of Neurology Haici Hospital Affiliated to Medical College of Qingdao University Department of Medical Imaging Haici Hospital Affiliated to Medical College of Qingdao University

Expression of miR-137 is downregulated in brain tissue from patients with depression and suicidal behavior, and is also downregulated in peripheral blood from stroke patients. However, it is not yet known if miR-137 acts as a bridge between stroke and depression. To test this, we used middle cerebral artery occlusion and chronic mild stress to establish a post-stroke depression model in rats. Compared with controls, we found significantly lower miR-137 levels in the brain and peripheral blood from post-stroke depression rats. Injection of a miR-137 antagonist into the brain ventricles upregulated miR-137 levels, and improved behavioral changes in post-stroke depression rats. Luciferase assays showed miR-137 bound to the 3＇UTR of Grin2A, regulating Grin2A expression in a neuronal cell line. Grin2A gene overexpression in the brain of post-stroke depression rats, no- ticeably suppressed the inhibitory effect of miR-137 on post-stroke depression. Overall, our results show that miR-137 suppresses Grin2A protein expression through binding to Grin2A mRNA, thereby exerting an inhibitory effect on post-stroke depression. Our results offer a new therapeutic direction for post-stroke depression.

关键词： neural regeneration brain injury post-stroke depression microRNA cerebrovascular disease Grin2A miR-137 neuroregeneration

Parallelizing of macro-scale pseudo-particle modeling for particle-fluid systems

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Science China Chemistry 2004年第5期47卷 434-442页

作者： TANG Dexiang GE Wei WANG xiaowei ma Jingsen GUO Li LI Jinghai Multi-phase Reaction Laboratory Institute of Process Engineering Chinese Academy of Sciences Beijing 100080 China Multi-phase Reaction Laboratory Institute of Process Engineering Chinese Academy of Sciences Beijing 100080 China Multi-phase Reaction Laboratory Institute of Process Engineering Chinese Academy of Sciences Beijing 100080 China Multi-phase Reaction Laboratory Institute of Process Engineering Chinese Academy of Sciences Beijing 100080 China Multi-phase Reaction Laboratory Institute of Process Engineering Chinese Academy of Sciences Beijing 100080 China Multi-phase Reaction Laboratory Institute of Process Engineering Chinese Academy of Sciences Beijing 100080 China

A parallel algorithm suitable for simulating multi-sized particle systems and multi- phase fluid systems is proposed based on macro-scale pseudo-particle modeling (maPPM). The algorithm employs space-decomposition of the computational load among the processing ele- ments (PEs) and multi-level cell-subdivision technique for particle indexing. In this algorithm, a 2D gas-solid system is simulated with the temporal variations of drags on solids, inter-phase slip velocities and solids concentration elaborately monitored. Analysis of the results shows that the algorithm is of good parallel efficiency and scalability, demonstrating the unique advantage of maPPM in simulating complex flows.

关键词： particle system, parallel algorithm, macro-scale pseudo-particle modeling, multi-level cell-subdivision.

Gold nanoparticles cause size-dependent inhibition of embryonic development during murine pregnancy

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Nano Research 2018年第6期11卷 3419-3433页

作者： xiaowei ma Xiaolong Yang Yufei Wang Juan Liu Shubin Jin Shuyi Li Xing-Jie Liang Chinese Academy of Sciences (CAS) Center for Excellence in Nanoscience CAS Key Laboratory for Biomedical Effects of Nanomaterials and Nanosafety National Center for Nanoscience and Technology of China No. 11 First North Road Zhongguancun Beijing 100190 China University of Chinese Academy of Sciences Beijing 100049 China College of Biotechnology Tianjin University of Science & Technology Tianjin 300457 China Tissue Engineering Lab Beijing Institute of Transfusion Medicine Beijing 100850 China Beijing Municipallnstitute of Labour Protection No. 55 Taoranting Road Xicheng District Beijing 100054 China

Gold nanoparticles （Au NPs） have been widely utilized in biomedical appli- cations owing to their attractive features and biocompatibility, which greatly increase the risk of humans＂ being exposed to Au NPs, including pregnant women. In contrast to mature cells, embryos are more susceptible to outside disruptive stimuli. Nonetheless, a possible inhibitory effect of nanomaterials on embryonic development is usually ignored as long as the NPs do not have significant cytotoxic effects. According to our results, a minimal ＂nontoxic＂ concentration of Au NPs during early pregnancy can have lethal inhibitory effects on embryos in vivo and in vitro. We conducted important experiments on the influence of Au NPs on embryonic development and found that Au NPs can disturb embryonic development in a size- and concentration-dependent manner. Au NPs of 15 nm in diameter downregulated the expression pattern of distinct germ layer markers both at mRNA and protein levels; this action prevented differentiation of all three embryonic germ layers. Consequentl~ fetal resorption was observed. Our work reveals the impact of Au NPs on embryonic development and will provide an important guidance and serve as a reference for biomedical applications of Au NPs with minimal side effects.

关键词： gold nanoparticles embryonic development fetal resorption differentiation

A Simple and Efficient Copper（Ⅱ） Complex as a Catalyst for N-Arylation of Imidazoles

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Chinese Journal of Chemistry 2013年第2期31卷 267-270页

作者： Yanli Jiao Nannan Yan Jianwei Xie xiaowei ma Ping Liu Bin Dai School of Chemistry and Chemical Engineering the Key Laboratory for Green Processing of Chemical Engineering of Xinjiang Bingtuan Shihezi University North 4th Road Shihezi Xinjiang 832003 China

Four inexpensive and air-/moisture-stable pyrrolecarbaldiminato-Cu complexes 1-4 were synthesized and evaluated to be a novel class of catalysts for the N-arylation of imidazoles with aryl halides. A variety of aryl iodides, bromides and activated aryl chlorides underwent the coupling with imidazoles, promoted by the catalyst 4, in moderate to good yields without the protection by an inert gas.

关键词： pyrrolecarbaldiminato-Cu complexes homogeneous catalyst N-arylation imidazoles N-heterocycles

Cu（II）-Catalyzed Ligand-Free Oxidation of Diarylmethanes and Second Alcohols in Water

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Chinese Journal of Chemistry 2017年第9期35卷 1391-1395页

作者： Jianglong Wu Yan Liu xiaowei ma Ping Liu Chengzhi Gu Bin Dai School of Chemistry and Chemical Engineering the Key Laboratory for Green Processing of Chemical Engineering of Xinjiang Bingtuan Shihezi University Shihezi Xinjiang 832003 China

We developed a simple and efficient Cu（II）-catalyzed ligand-free oxidation of diarylmethanes and secondary alcohols using 70% ten-butyl hydroperoxide （TBHP） in water. A series of diarylmethanes were directly oxidized into diaryl ketones in 67%--98% yields. Additionally, various secondary alcohols were also transformed into the desired products in 48%--98% yields. Importantly, the catalytic system in the absence of any organic solvent, surfactant, or phase transfer agent, had a wide substrate scope and a high tolerance for various functional groups.

关键词： Cu-catalyzed oxidation diarylmethane ligand-free water