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Chinese Journal of Polymer Science 2016年第7期34卷 830-837页

作者： si-hua guo fang-yuan zheng fang zeng 吴水珠 College of Materials Science and Engineering State Key Laboratory of Luminescent Materials and Devices South China University of Technology Guangzhou 510640 China

A simple and effective polymer fluorescent thermosensitive system was successfully developed based on the synergistic effect of excimer/monomer interconversion of pyrene derivatives and electrostatic interaction between polyelectrolyte and charged fluorophore. As for the system, the excimer-monomer conversion, thermosensitive behavior and thermo-responsive reversibility were investigated experimentally. Temperature variation and temperature-distribution induced fluorescence changes can be observed directly by naked eyes. Thus, this polymer system holds promise for serving as a fluorescent thermometer.

关键词： Polymer fluorescent thermometer Temperature-responsive Electrostatic interaction Aggregation Deaggregation

Mesoscale study on explosion-induced formation and thermochemical response of PTFE/Al granular jet

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Defence Technology（防务技术） 2023年第5期23卷 112-125页

作者： Yuan-feng zheng Zhi-jian zheng Guan-cheng Lu Hai-fu Wang huan-guo Guo State Key Laboratory of Explosion Science and Technology Beijing Institute of TechnologyBeijing100081China

The dynamic formation,shock-induced inhomogeneous temperature rise and corresponding chemical reaction behaviors of PTFE/Al reactive liner shaped charge jet(RLSCJ)are investigated by the combination of mesoscale simulation,reaction kinetics and chemical energy release test.A two-dimensional granular model is developed with the randomly normal distribution of aluminum particle sizes and the particle delivery ***,the granular model is employed to study the shock-induced thermal behavior during the formation and extension processes of RLSCJ,as well as the temperature history curves of aluminum *** simulation results visualize the motion and temperature responses of the RLSCJ at the grain level,and further indicate that the aluminum particles are more likely to gather in the last two-thirds of the jet along its *** analysis shows that the shock,collision,friction and deformation behaviors are all responsible for the steep temperature rise of the reactive *** addition,a shock-induced chemical reaction extent model of RLSCJ is built based on the combination of the Arrhenius model and the Avrami-Erofeev kinetic model,by which the chemical reaction growth behavior during the formation and extension stages is described *** model indicates the reaction extent highly corresponds to the aluminum particle temperature history at the formation and extension *** last,a manometry chamber and the corresponding energy release model are used together to study the macroscopic chemical energy release characteristics of RLSCJ,by which the reaction extent model is verified.

关键词： Reactive materials Shaped charge Mesoscale simulation Formation Thermochemical response

The progress of telestroke in China

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Stroke & Vascular Neurology 2017年第3期2卷 168-171页

作者： Gang Zhao huan huang fang Yang Department of Neurology Xijing HospitalThe Fourth Military Medical UniversityXi'anChina

Stroke remains the leading cause of death in *** disparity of distribution in specialists and hospitals affects access to timely stroke ***,the use of telemedicine for stroke,may be the solution to access to stroke *** can improve the rate of successful intravenous thrombolysis and shorten the time to *** we review the progress of telestroke in China.

关键词： China. intravenous death

On Compact Hermitian Manifolds with Flat Gauduchon Connections

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Acta Mathematica Sinica,English Series 2018年第8期34卷 1259-1268页

作者： Bo YANG fang Yang zheng School of Mathematical Sciences Xiamen University Xiamen 361005 P. R. China Department of Mathematics Zhejiang Normal University Jinhua 321004 P. R. China Department of Mathematics The Ohio State University 231 West 18th Avenue Columbus OH 43210 USA

Given a Hermitian manifold （M-n,g）, the Gauduchon connections are the one parameter family of Hermitian connections joining the Chern connection and the Bismut connection. We will call△=（1-s/2）△c＋s/2△b the s-Gauduchon connection of M, where △c and △b are respectively the Chern and Bismut connections. It is natural to ask when a compact Hermitian manifold could admit a flat s-Gauduchon connection. This is related to a question asked by Yau. The cases with s = 0 （a flat Chern connection） or s = 2 （a flat Bismut connection） are classified respectively by Boothby in the 1950s or by the authors in a recent joint work with Q. Wang. In this article, we observe that if either s 〉 4＋2√3 ≈ 7.46 or s 〈 4- 2√3≈ 0.54 and s ≠ 0, then g is Kahler. We also show that, when n = 2, g is always Kahler unless s=2. Therefore non-Kahler compact Gauduchon fiat surfaces are exactly isosceles Hopf surfaces.

关键词： Hermitian manifolds Hermitian connections Kahler manifolds

A New Network Coding Mechanism Balancing Coding Opportunities, Energy and QoS in WSNs

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China Communications 2014年第6期11卷 108-118页

作者： zheng Kangfeng WANG Xiujuan ZHA Xuan XIAO huan School of Computer Science Beijing University of Posts and Telecommunications School of Computer Science Beijing University of Technology

A new Network Coding mechanism in WSNs(Wireless Sensor Networks), which is named COEQ and aims at balancing coding opportunities, energy and QoS, is proposed and analyzed. Implemented on the basis of traditional AODV protocol, COEQ evaluates several metrics of paths comprehensively with TOPSIS method including minimum remaining energy, coding opportunities, QoS and so on, so as to select the optimal transmitting route. Experiments on NS[2] show that COEQ can improve throughput and save energy when the transmitting rate is low.

关键词： network coding wireless sensor network QoS TOPSIS

Carbon emission analysis of a residential building in China through life cycle assessment

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Frontiers of Environmental Science & Engineering 2016年第1期10卷 150-158页

作者： Yin ZHANG Xuejing zheng huan ZHANG Gaofeng CHEN Xia WANG School of Environmental Science and Engineering Tianjin University Tianjin 300072 China China Architecture Design & Research Group Beijing 100044 China

In this paper, a quantitative life cycle model for carbon emission accounting was developed based on the life cycle assessment （LCA） theory. A residential building in Sino-Singapore Tianjin Eco-city （Tianjin, China） was selected as a sample, which had been constructed according to the concept of green environmental protection and sustainable development. In the scenario of this research, material production, construction, use and maintenance, and demolition phases were assessed by building carbon emission models. Results show that use and maintenance phase and material production phase are the most significant contributors to the life cycle carbon emissions of a building. We also analyzed some factor influences in LCA, including the thickness of the insulating layer and the length of building service life. The analysis suggest that thicker insulating layer does not necessarily produce less carbon emissions in the light of LCA, and if service life of a building increases, its carbon emissions during the whole life cycle will rise as well but its unit carbon emission will decrease inversely. Some advices on controlling carbon emissions from buildings are also provided.

关键词： life cycle assessment carbon emission factorinfluence analysis

Osthole attenuates pulmonary arterial hypertension by the regulation of sphingosine 1-phosphate in rats

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Chinese Journal of Natural Medicines 2020年第4期18卷 308-320页

作者： YAO Li YANG Yu-Xia CAO Hui REN huan-huan NIU zheng SHI Ling Department of Medicinal Chemistry and Natural Medicine Chemistry Department of PharmacognosyCollege of PharmacyHarbin Medical UniversityHarbin 150081China State-Province Key Laboratory of Biomedicine-Pharmaceutics of China Harbin Medical UniversityHarbin 150081China Department of Pharmacology College of PharmacyHarbin Medical UniversityHarbin 150081China

Osthole is observed to have the capacity to treat pulmonary arterial hypertension(PAH) in rats, but molecular mechanism is still unknown. The present study aims to discover therapeutic targets and explore therapeutic mechanism of osthole against PAH from metabolic perspective. A rat model with PAH was successfully established with MCT, following osthole administration, then untargeted metabolomics assay was performed using UPLC-Q-TOF-MS to identify differential metabolites and associated metabolic pathways, at last mechanism investigation was done by qRT-PCR, Western blot and ELISA. Differential metabolites characterized in rats with PAH were mostly assigned to sphingolipid metabolism, synthesis of unsaturated fatty acids, glycolysis, nucleotide metabolism, steroid hormone biosynthesis. Furthermore, osthole reversed high level of S1 P by modulating metabolic enzyme Sphk1 in rats with PAH. In addition, osthole inhibited the expression of Sphk1 by downregulating microRNA-21, phosphorylation of Akt, phosphorylation of mTOR in vivo and in vitro. These results demonstrated that metabolomics is a promising approach to discover potential drug target for PAH treatment. Importantly, our findings further elucidated therapeutic mechanism of osthole, a natural product, having a role of metabolic regulator to potentially treat PAH by targeting inhibition of Sphk1/S1 P via microRNA-21-PI3 K/Akt/mTOR signal pathway. Altogether, this discovery paves a critical foundation for enabling osthole to be a candidate compound to treat PAH.

关键词： Pulmonary arterial hypertension Osthole Metabolomics Sphk1/S1P MicroRNA-21-PI3K/Akt/mTOR Therapeutic mechanism

Fluorinated pillared-layer metal-organic framework microrods for improved electrochemical cycling stability

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Chinese Chemical Letters 2021年第12期32卷 3817-3820页

作者： Shasha zheng Yue Ru Huaiguo Xue huan Pang School of Chemistry and Chemical Engineering Yangzhou UniversityYangzhou 225009China

Developing metal-organic framework(MOF)-based materials with good cyclic stability is the key to their practical application. Fluorinated organic compounds are usually highly chemically stability due to the high electronegativity of fluorine. Also, the pillared-layer structures based on coordination bonds have better structure and thermal stability than those based on hydrogen bonds. Herein, the fluorinated pillared-layer [Ni(2,3,4,5-tetrafluorobenzoic acid)(4,4-bipyridine)]nMOF([Ni(TFBA)(Bpy)]n) materials were constructed through a facile room-temperature solution reaction and used as electrode materials for supercapacitors. Surprisingly, the size/morphology of Ni(TFBA)(Bpy)nMOFs could be adjusted by varying the synthesis time. Benefting from the short ion diffusion length, unique pillar-layer structure, and strong intercomponent synergy of organic ligands, the Ni(TFBA)(Bpy)nMOF microrods showed a higher electrochemical energy storage capability than bulk MOFs. At the same time, compared to the non-fluorinated [Ni(benzoic acid)(Bpy)]nMOFs(31.5% capacitance decay), the fluorinated Ni(TFBA)(Bpy)n MOFs have a higher cycle stability with only 2.6% capacitance loss after 5000 cycles at 3 m A/cm^(2).

关键词： Fluorinated metal-organic framework Pillar-layer structure Microrod Cyclic stability Electrochemical energy storage Supercapacitor

Applications of M_xSe_y(M=Fe, Co, Ni) and Their Composites in Electrochemical Energy Storage and Conversion

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Nano-Micro Letters 2019年第3期11卷 46-78页

作者： Huijie Zhou Xiaxia Li Yan Li Mingbo zheng huan Pang School of Chemistry and Chemical Engineering Guangling College Yangzhou University

Transition-metal selenides(M_xSe_y,M = Fe,Co,Ni)and their composites exhibit good storage capacities for sodium and lithium ions and occupy a unique position in research on sodium-ion and lithium-ion *** and their composites are used as active materials to improve catalytic ***,low electrical conductivity,poor cycle stability,and low rate performance severely limit their *** review provides a comprehensive introduction to and understanding of the current research progress of M_xSe_y and their ***,this review proposes a broader research platform for these materials,including various bioelectrocatalytic performance tests,lithium-sulfur batteries,and fuel *** synthesis method and related mechanisms of M_xSe_y and their composites are reviewed,and the effects of material morphologies on their electrochemical performance are *** advantages and disadvantages of M_xSe_y and their composites as well as possible strategies for improving the storage and conversion of electrochemical energy are also summarized.

关键词： M_xSe_y Battery Supercapacitor Electrocatalysis

Year-round changes in tropospheric nitrogen dioxide caused by COVID-19 in China using satellite observation

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Journal of Environmental Sciences 2023年第10期132卷 162-168页

作者： Zhenyu Luo Hailian Xu Zhining Zhang Songxin zheng huan Liu State Key Joint Laboratory of ESPC State Environmental Protection Key Laboratory of Sources and Control of Air Pollution ComplexSchool of EnvironmentTsinghua UniversityBeijing 100084China

The lockdown policy deals a severe blow to the economy and greatly reduces the nitrogen oxides(NOx)emission in China when the coronavirus 2019 spreads widely in early *** we use satellite observations from Tropospheric Monitoring Instrument to study the year-round variation of the nitrogen dioxide(NO_(2))tropospheric vertical column density(TVCD)in *** NO_(2)TVCD reveals a sharp drop,followed by small fluctuations and then a strong rebound when compared to *** the end of 2020,the annual average NO_(2)TVCD declines by only 3.4%in Chinamainland,much less than the reduction of 24.1%in the lockdown *** the basis of quantitative analysis,we find the rebound of NO_(2)TVCD is mainly caused by the rapid recovery of economy especially in the fourth quarter,when contribution of industry and power plant on NO_(2)TVCD continues to *** revenge bounce of NO_(2)indicates the emission reduction of NOx in lockdown period is basically offset by the recovery of economy,revealing the fact that China’s economic development and NOx emissions are still not *** efforts are still required to stimulate low-pollution development.

关键词： COVID-19 Tropospheric NO2 TROPOMI Economy recovery Environment sustainability