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The Accelerated Thermo-Oxidative Aging Characteristics of Wood Fiber/Polycaprolactone Composite:Effect of Temperature,Humidity and Time

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Journal of Renewable Materials 2021年第12期9卷 2209-2222页

作者： Shuang Si qian tang Xingong Li Central South University of Forestry and Technology Changsha410004China

This study investigated the characteristics of wood fiber/polycaprolactone composite after an artificial accelerated thermo-oxidative aging *** effect of time,temperature and humidity during the treatment on their mechanical,chemical and morphology properties were *** composite was prepared from melted wood fibers and modified polycaprolactone by a molding process.A temperature and humidity controllable test chamber was used for the thermo-oxidative aging of the *** thermo-oxidative aging caused surface of the composite to be much more rougher and even a few cracks and holes appeared on *** to the spectra of Fourier Transform Infrared(FTIR)and Gel Permeation Chromatography(GPC),C=O in the molecular chain of polycaprolactone was hydrolyzed and C–O was broken after the aging treatment,which resulted in a reduction in average molecular weight of the ***,results showed that the mechanical strength decreased a lot with the increase in time,temperature and humidity,and the effect of temperature and humidity was more significant compared with that of *** the temperature and humidity during thermo-oxidative aging treatment could accelerate the aging of composite,which provided a quick and effective method for evaluating the aging resistance of the composite.

关键词： Wood fiber polycaprolactone wood plastic composite thermo-oxidative aging

Estimating and Mapping Extreme Ice Accretion Hazard and Load Due to Freezing Rain at Canadian Sites

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International Journal of Disaster Risk Science 2023年第1期14卷 127-142页

作者： Chao Sheng qian tang H.P.Hong Department of Civil and Environmental Engineering University of Western OntarioLondonOntarioN6A 5B9Canada

The ice accretion load in Canadian structural design codes is developed based on an operational ice accretion prediction *** the present study,three models are employed to predict the ice accretion amount on a flat surface and horizontal wire at Canadian *** results confirm that the model used by Canadian practice for predicting ice accretion leads to a conservative estimate as compared to the remaining two *** results also indicate that the use of the Gumbel distribution for the annual maximum ice accretion is adequate for regions prone to ice accretion and that the lognormal distribution may be considered for regions with a moderate or negligible amount of ice *** of the ice accretion hazard at five selected Canadian sites are *** analysis of an equivalent wind speed that is concurrent with the iced wire is carried out,showing that the concurrent wind speed for the 50-year return period value of the annual maximum ice accretion amount is smaller than the 50-year return period value of the annual maximum wind *** is shown that the statistical characteristics of the annual maximum concurrent wind speed on iced wire differ from that of the annual maximum wind speed.

关键词： Canada Concurrent wind speed Hazard mapping Ice accretion Probabilistic analysis

The RNA N^(6)-methyladenosine demethylase ALKBH9B modulates ABA responses in Arabidopsis

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Journal of Integrative Plant Biology 2022年第12期64卷 2361-2373页

作者： Jun tang Junbo Yang qiang Lu qian tang Shuyan Chen Guifang Jia Synthetic and Functional Biomolecules Center Bejing National Laboratory for Molecular SciencesKey Laboratory of Bioorganic Chemistry and Molecular Engineering of Ministry of EducationDepartment of Chemical BiologyCollege of Chemistry and Molecular EngineeringPeking UniversityBeijing 100871China Peking-Tsinghua Center for Life Sciences Beijing 100871China

The mRNA modification N^(6)-methyladenosine(m^(6)A)plays vital roles in plant development and biotic and abiotic stress *** RNA m^(6)A demethylase ALKBH9 B can remove m^(6)A in alfalfa mosaic virus RNA and plays roles in alfalfa mosaic virus infection in ***,it is unknown whether ALKBH9 B also exhibits demethylation activity and has a biological role in endogenous plant *** demonstrated here that mRNA m^(6)A modification is induced by the phytohormone abscisic acid(ABA)and that ALKBH9 B has m^(6)A demethylation activity on endogenous *** out ALKBH9 B led to hypersensitivity to ABA treatment during seed germination and early seedling *** further showed that ALKBH9 B removes the m^(6)A modification in the ABA INSENSITIVE 1(ABI1)and BRI1-EMS-SUPPRESSOR 1(BES1)transcripts following ABA treatment,affecting the stability of these ***,we determined that ALKBH9 B acts genetically upstream of the transcription factors ABI3 and ABI5,and its regulatory function in ABA responses depended on ABI3 and *** findings reveal the important roles of the m^(6)A modification in ABA responses and highlight the role of ALKBH9 Bmediated m^(6)A demethylation in regulating ABA responses post-transcriptionally.

关键词： ABA ALKBH9B Arabidopsis demethylase m^(6)A RNA modification

Effects of Corridor Networks on Plant Species Composition and Diversity in an Intensive Agriculture Landscape

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Chinese Geographical Science 2014年第1期24卷 93-103页

作者： tang qian LIANG Guofu LU Xunling DING Shengyan Key Laboratory of Geospatial Technology for the Middle and Lower Yellow River Regions Ministry of Education College of Environment and Planning Henan University College of Life Science Henan University

The development of modern agriculture has resulted in much homogenization of the landscape consisting of large patches of farmland,so small remnant non-crop habitats especially linear corridors play an important role in the conservation of species and the maintenance of ecosystem ***,little attention has been paid to the effects of corridors structural characteristics on the plant species restricted to such *** this study,we selected three types of corridors including ditch,hedgerow and road,and analyzed their structural *** plant species presented in these corridors were investigated,and the species diversity,abundance and frequency were ***,spatial arrangements of corridors were classified into different types to discuss whether there were significant effects of corridor network on plant *** results show that three types of corridors have different effects on plant species composition and *** one-one combined corridor networks and total network associated by three corridors have more complex structural features than each single type of ***,there is no strong correlation between the corridor networks with their plant *** suggest that carrying out a pointed vegetation survey at corridor intersections to further test the relationships between structural features of corridor and plants is necessary.

关键词： habitat corridor spatial arrangement plant diversity connectivity intensive agriculture landscape

Modulation of Behavior and Glutamate Receptor mRNA Expression in Rats after Sub-chronic Administration of Benzo(a)pyrene

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Biomedical and Environmental Sciences 2011年第4期24卷 408-414页

作者： tang qian XIA YinYin CHENG ShuQun TU BaiJie Department of Occupational and Environmental Medicine College of Public Health Chongqing MedicalUniversity Chongqing 400016 Sichuan China

Objective The present study aimed to test whether exposure to benzo（a）pyrene [B（a）P] affects spatial learning and short-term memory by modulating the expression of the Gria1 and Grin2a glutamate receptor subunit genes in the *** Thirty-six 21-24-day-old,male rats were randomly assigned into high-,medium-,and low-dose toxin exposure groups （6.25,2.5,and 1 mg/kg,respectively） and a control group,each containing nine *** behavioral performance of adult rats exposed to sub-chronic administration of B（a）P was monitored by learning and memory tests （Morris water maze）.Real-time PCR assays were used to quantify Gria1 and Grin2a gene expression in the *** At medium and high doses,B（a）P impaired spatial learning *** crossing-platform-location frequency and the time spent swimming in the platform area,which both relate to short-term memory,were significantly decreased in B（a）P-treated rats compared with *** level of Gria1 mRNA increased 2.6-5.9-fold,and the level of Grin2a mRNA increased 10-14.5-fold,with a greater fold increase associated with higher doses of B（a）*** We demonstrated that sub-chronic administration of B（a）P inhibits spatial learning and short-term memory,and increases Gria1 and Grin2a expression in the *** suggests a relationship of B（a）P exposure levels with Gria1 and Grin2a expression and impairment of short-term and spatial memory.

关键词： Benzo(a)pyrene Gria1 Grin2a

Synthesis of novel chiral fluorinating agents,(+)-and(-)-N-fluoro-3-methyl-3-(4-methylphenyl)-2H-benzo[e][1,2]thiazine-1,1,4-triones

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Chinese Chemical Letters 2008年第8期19卷 907-910页

作者： Hui Min Sun Zhao Peng Liu Long qian tang National Institute for the Control of Pharmaceutical and Biological Products Beijing 100050 China Department of Organic Chemistry School of Pharmaceutical Sciences Shandong University Jinan 250012 China

Treatment of N-t-butylbenzenesulfonamide with an excess of BuLi, followed by the reaction with methyl 2-（4-methylphenyl）propanoate, gave the corresponding 2-carboxybenzenesulfonamide, which underwent a sequence of consecutive N-deprotective cyclization process mediated by TMSCI-NaI-MeCN reagent to afford the N-sulfonylimine. Following the bromination and ring expansion, 3-methyl-3-（4-methylphenyl）-2H-benzo[e][1,2]thiazine-l,l,4-trione was obtained. Optical resolution of the racemic benzosultam using （-）-menthoxyacetyl chloride, furnished the optically *** （＋）- and （-）-3-methyl-3-（4-methylphenyl）-2H- benzo[e][1,2]thiazine-1,1,4-triones, which were fluorinated with FC103 to produce the corresponding chiral N-F agents.

关键词： Benzosultams Cyclization TMSCI/Nal/MeCN Enantioselective electrophilic fluorinating agent Chirality

Shear-thickening behavior of Fe-ZSM5 zeolite slurry and its removal with alumina/boehmites

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International Journal of Minerals,Metallurgy and Materials 2018年第6期25卷 682-688页

作者： Xiao-guang Liu Yan Li Wen-dong Xue Jia-lin Sun qian tang Department of Inorganic Nonmetallic Materials School of Materials Science and Engineering University of Science and Technology Beijing Atmospheric Environment Department Chinese Academy for Environmental Planning

A cryogenic scanning electron microscopy（cryo-SEM） technique was used to explore the shear-thickening behavior of Fe-ZSM5 zeolite pastes and to discover its underlying mechanism. Bare Fe-ZSM5 zeolite samples were found to contain agglomerations, which may break the flow of the pastes and cause shear-thickening behaviors. However, the shear-thickening behaviors can be eliminated by the addition of halloysite and various boehmites because of improved particle packing. Furthermore, compared with pure Fe-ZSM5 zeolite samples and its composite samples with halloysite, the samples with boehmite（Pural SB or Disperal） additions exhibited network structures in their cryo-SEM images; these structures could facilitate the storage and release of flow water, smooth paste flow, and avoid shear-thickening. By contrast, another boehmite（Versal 250） formed agglomerations rather than network structures after being added to the Fe-ZSM5 zeolite paste and resulted in shear-thickening behavior. Consequently, the results suggest that these network structures play key roles in eliminating the shear-thickening behavior.

关键词： Fe-ZSM5 zeolite cryogenic scanning electron microscopy shear-t^ickening behavior zeta potential boel^nite

Chain-flip plate triboelectric nanogenerator arranged longitudinally under water for harvesting water wave energy

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Nano Research 2023年第9期16卷 11900-11906页

作者： Yan Du qian tang Shaoke Fu Chuncai Shan Qixuan Zeng Hengyu Guo Chenguo Hu Department of Applied Physics Chongqing UniversityChongqing 400044China

Triboelectric nanogenerator(TENG)is a new cost-effective blue energy harvesting technology for its great performance in low ***,many related energy harvesters operate on water surface,ignoring the ocean’s ***,a chainflipped plate TENG(CFP-TENG),consisting of longitudinally arranged repeating units,is proposed to collect wave *** chain structure design allows the surface wave energy to act effectively on the underwater *** maximum output power per unit ocean area reaches 1.5 W·m^(-2) at a loading resistance of 30 MΩ.Optimization of device parameters and application demonstrations are *** with previous works,the utilization rate of wave energy has been significantly *** work not only provides a new method to optimize the output of TENG but also makes a crucial step in promoting practical applications of TENG in renewable blue energy.

关键词： triboelectric nanogenerator chain-flip plate wave energy blue energy

Semi-empirical and semi-quantitative lightweight shielding design method

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Nuclear Science and Techniques 2023年第3期34卷 109-124页

作者： Song-Chuan Zheng Qing-Quan Pan Huan-Wen Lv Song-qian tang Xiao-Jing Liu College of Smart Energy Shanghai Jiao Tong UniversityShanghai 200240China School of Nuclear Science and Engineering Shanghai Jiao Tong UniversityShanghai 200240China Science and Technology on Reactor System Design Technology Laboratory Nuclear Power Institute of ChinaChengdu 610200China

The lightweight shielding design of small reactors is a popular research *** on a small helium-xenon-cooled solid reactor,the effects of neutron and photon shielding sequence and the number of shielding layers on the radiation dose were first *** was found that when photons were shielded first and the number of shielding layers was odd,the radiation dose could be significantly *** reduce the weight of the shielding body,the relative thickness of the shielding layers was optimized using the genetic *** optimized scheme can reduce the radiation dose by up to 57%and reduce the weight by 11.84%.To determine the total thickness of the shielding layers and avoid the local optimal solution of the genetic algorithm,a series of formulas that describes the relationship between the total thickness and the radiation dose was developed through large-scale calculations.A semi-empirical and semi-quantitative lightweight shielding design method is proposed to integrate the above shielding optimization method that verified by the Monte Carlo ***,a code,SDIC1.0,was developed to achieve the optimized lightweight shielding design for small *** was verified that the difference between the SDIC1.0 and the RMC code is approximately 10%and that the computation time is shortened by 6.3 times.

关键词： Small reactor Lightweight Shielding calculation Genetic algorithm