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Journal of Materials Science & Technology 2010年第6期26卷 572-576页

作者： Yunying Wang Jiangyan Meng qing Zhao shuhua qi School-of Science Northwestern Polytechnical University Xi'an 710072 China Department of Materials Science and Engineering Nanchang Hangkong University Nanchang 330063 China

The paper presented accelerated ageing test results of a durability study on ortho-phthalic anhydride-type unsaturated polyester resin （191#） and its glass-fiber reinforcement polyester composites （GFRPC）. The samples were exposed in an artificial xenon arc lamp ageing cell or a thermo-oxidative ageing cell. Morphology and gloss of the specimens were investigated by using a microscope and a gloss-meter, respectively. The tensile strength, bending strength and inter-laminar shear strength （ILSS） of GFRPC were tested before and after exposure, and were considered to evaluate the durability performance of this material. The polyester resin was analyzed by fourier transform infrared （FT-IR） spectroscopy. The results showed that the glossiness of the specimens got worse and some cracks appeared on their surface during the course of ageing, the tensile strength and bending strengths of the specimens first increased and then decreased. The ILSS of the composites decreased after they were aged in the xenon arc lamp cell, but increased while they were aged in the thermo-oxidative cell. The changes of these trends become more obvious during ageing in the xenon arc lamp cell, so the main influencing factor leading to the failure of this material is UV irradiation.

关键词： Ortho-phthalic Artificial thermo-oxidation ageing Artificial xenon arc lampageing UV irradiation Inter-laminar shear strength (ILSS)

Assessing effects of land use and land cover changes on hydrological processes and sediment yield in the Xunwu River watershed, Jiangxi Province, China

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Frontiers of Earth Science 2022年第3期16卷 819-833页

作者： Guihua LIU Britta SCHMALZ qi ZHANG shuhua qi Lichao ZHANG Shiyu LIU School of Geography and Environment Key Laboratory of Poyang Lake Wetland and Watershed Research(Ministry of Education)Jiangxi Normal UniversityNanchang 330022China Department of Civil and Environmental Engineering Key Laboratory of Engineering Hydrology and Water ManagementTechnical University of DarmstadtDarmstadt 64287Germany Key Laboratory of Watershed Geographic Sciences Nanjing Institute of Geography and LimnologyChinese Academy of SciencesNanjing 210008China College of Land Resources and Environment Jiangxi Agricultural UniversityNanchang 330045China Jiangxi Key Laboratory of Soil Erosion and Prevention Jiangxi Institute of Soil and Water ConservationNanchang 330029China

The effects of land use and land cover changes on hydrological processes and sediment yield are important issues in regional *** Xunwu River catchment located in the red soil hilly region of southern China has experienced drastic land use changes in the past 30 years,with orchard increases of approximately 42%and forest decreases of approximately 40%.These changes have resulted in some alterations of runoff and sediment *** study aims to evaluate effects of land use/land cover on runoff and sediment yield in the Xunwu River *** SWAT model(Soil and Water Assessment Tool)was used for runoff and sediment simulation,and the results met the requirements of the model acceptance based on evaluation statistics of R^(2)(the coefficient of determination),PBIAS(percent bias),and NSE(Nash-Sutcliffe efficiency).Four land use scenarios representing the gradual expansion of orchards in the past 26 years were developed for assessment of hydrological processes and sediment yield *** a result,both runoff and sediment yield were changed insignificantly with decrease rates of 1.84%and 5.29%,*** addition,surface runoff accounts for the largest share of the runoff components,but the lateral flow changed more than other runoff components with a decrease rate of 10.96%.The results show that orchard expansion does not reveal severe water and soil *** study can contribute to the rational utilization of land and water resources in the red soil hilly area of southern Jiangxi Province.

关键词： land use change orchard expansion red soil hilly region SWAT runoff sediment

Phylogenetic diversity and bioactivity of culturable deepsea-derived fungi from Okinawa Trough

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Journal of Oceanology and Limnology 2021年第3期39卷 892-902页

作者： Xiaoyong ZHANG Yiyang LI Zonghe YU Xiao LIANG shuhua qi Joint Laboratory of Guangdong Province and Hong Kong Region on Marine Bioresource Conservation and Exploitation College of Marine SciencesSouth China Agricultural UniversityGuangzhou 510642China Key Laboratory of Tropical Marine Bio-resources and Ecology/RNAM Center for Marine Microbiology/Guangdong Key Laboratory of Marine Material Medical South China sea Institute of OceanologyChinese Academy of SciencesGuangzhou 510301China Southern Marine Science and Engineering Guangdong Laboratory(Guangzhou) Guangzhou 511458China

Deep-sea sediments are now recognized as a home for rich and largely microbial ***,it has been believed in an increasing number of studies that bacteria could be abundant in deepsea sediments of many types;however,fungi in deep-sea sediments remain relatively *** phylogenetic diversity and bioactivity of culturable deep-sea-derived fungi from Okinawa Trough sediments were investigated in traditional method combined with fungal identification of molecular biology in this study.A total of 76 isolates belonged to 15 fungal taxa were recovered in a harsh condition of low nutrient and low temperature,indicating that the fungal communities in deep-sea sediments from Okinawa Trough were relatively abundant and ***,Cladosporium,and Penicillium were the dominant fungal genera,while Mycosphaerella,Purpureocillium,and Schizophyllum were relatively rare in the deep-sea sediments from Okinawa *** the six genera recovered,Mycosphaerella was firstly recovered from deep-sea sediments in this ***,about 75%of the extracts from the 15 fungal representative isolates displayed distinct bioactivity against at least one indicator bacterium or marine macrofouler,emphasizing the potentials of these deep-sea-derived fungi from Okinawa Trough as producers of bioactive ***,isolates Cladosporium oxysporum SCSIO z001 and Penicillium citrinum SCSIO z049 displayed a wide spectrum of bioactivities,isolates Cladosporium cladosporioides SCSIO z015,Cladosporium sphaerospermum SCSIO z030,and Penicillium verruculosum SCSIO z007 exhibited a strong anti-bacterial-growth activity,and isolate Penicillium chrysogenum SCSIO z062 displayed a strong anti-larval-settlement *** results suggest that these isolates deserved further study as potential sources of novel bioactive metabolites.

关键词： deep-sea-derived fungi phylogenetic diversity bioactivity Okinawa Trough hydrothermal vents

Layered-structure N-doped expanded-graphite/boron nitride composites towards high performance of microwave absorption

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Journal of Materials Science & Technology 2022年第18期113卷 71-81页

作者： Zhuguang Nie Yang Feng qing Zhu Ying Xia Liping Luo Lan Ma Jie Su Xingman Hu Rumin Wang shuhua qi School of Chemistry and Chemical Engineering Northwestern Polytechnical UniversityXi’an 710072China

High-efficiency microwave absorbers with broadband absorption are strongly desired for electromag-netic ***,we successfully synthesized a hybrid microwave absorbing material with two-dimensional layered structure,which consisted of expanded graphite(EG)and boron nitride(BN).The introduction of BN is to regulate the conductivity of EG and also to improve the thermal stability of the composite *** ultrathin BN nano-sheets were uniformly wrapped on the EG sheets via chemi-cal vapor *** to the dielectric loss and conductive loss,the as-prepared hybrid material exhibited high performance for microwave *** effective absorbing bandwidth(reflection loss value<-10 dB)was achieved up to 9.37 GHz with the thickness of 2.4 mm in the frequency range of 5.75-6.98 GHz and 9.86-18 *** the minimum reflection loss was-51.58 dB at the thickness of 3 *** excellent performance of microwave absorption was attributed to the dielectric loss,interfacial polarization loss and optimized impedance ***,compared to pure EG,the thermal de-composition temperature of EG/BN composite materials had increased by about 100℃which was up to 714℃.Taking the advantages of high thermal stability of BN as well as the fine microwave absorbability of EG,the EG/BN composites would be applied in high-temperature microwave absorbing fields.

关键词： Layered-structure Expanded graphite Boron nitride Microwave absorption

高热导率Ag-AlN/聚丙烯酸酯导电胶黏剂的制备与性能

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复合材料学报 2016年第3期33卷 558-563页

作者：马缓齐暑华西北工业大学理学院西安710072

分别采用无钯化学镀法和溶液聚合法制备了Ag-AlN和聚丙烯酸酯胶黏剂,并采用超声辅助溶液共混法制备了高热导率Ag-AlN/聚丙烯酸酯导电胶黏剂。采用XRD、EDS和SEM等对Ag-AlN的结构进行分析。结果表明:经过高温和酸性清洗液清洗等处理,AlN... 详细信息

分别采用无钯化学镀法和溶液聚合法制备了Ag-AlN和聚丙烯酸酯胶黏剂,并采用超声辅助溶液共混法制备了高热导率Ag-AlN/聚丙烯酸酯导电胶黏剂。采用XRD、EDS和SEM等对Ag-AlN的结构进行分析。结果表明:经过高温和酸性清洗液清洗等处理,AlN表面的杂质被除去,并且在AlN表面形成致密的Al2O3层,采用无钯化学镀法制备的Ag-AlN具有优异的电导率和热导率,其电导率由AlN的10-13 S/cm提高到了7.06×102 S/cm,热导率由AlN的170W/(m·K)提高到了230W/(m·K)。经过计算,Ag-AlN表面的Ag镀层质量分数约为13%,Ag镀层的厚度约为80nm。当导电胶黏剂中Ag-AlN填料的质量分数为50%时,Ag-AlN/聚丙烯酸酯导电胶黏剂的电导率为1.9S/cm,热导率为3.1 W/(m·K)。

关键词：化学镀 AlN 导电胶黏剂电导率热导率聚丙烯酸酯树脂

Gould-Hsu Inversion Chains and Their Applications

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Journal of Mathematical Research with Applications 2012年第2期32卷 167-173页

作者： Hongmei LIU,Shuyan DING,shuhua qi School of Science,Dalian Nationalities University,Liaoning 116600,P.R.China School of Science Dalian Nationalities University Liaoning 116600

In this paper,by means of Gould-Hsu inverse series relations,we establish several Gould-Hsu inversion *** consequence,some new transformation formulae as well as some famous hypergeometric series identities are derived.

关键词： Gould-Hsu inversion combinatorial identities hypergeometric series.

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鄱阳湖水利枢纽工程水位调控方案的探讨

地理学报 2013年第1期68卷 118-126页

作者：齐述华廖富强江西师范大学鄱阳湖湿地与流域研究教育部重点实验室南昌330022 江西师范大学地理与环境学院南昌330022

利用历史水文资料、越冬候鸟分布调查资料及基础地理数据等,从鄱阳湖形态的历史演变和鄱阳湖越冬候鸟生境保护的角度,探讨鄱阳湖水利枢纽工程的水位调控方案。研究得到以下结论和建议:(1)在维持鄱阳湖形态不变的情况下,为有效保护越冬... 详细信息

利用历史水文资料、越冬候鸟分布调查资料及基础地理数据等,从鄱阳湖形态的历史演变和鄱阳湖越冬候鸟生境保护的角度,探讨鄱阳湖水利枢纽工程的水位调控方案。研究得到以下结论和建议:(1)在维持鄱阳湖形态不变的情况下,为有效保护越冬候鸟生境不受水利枢纽工程水位调控的影响,工程调控水位不宜超过12m,但由于低水位运行不利于水利枢纽工程工程效益的发挥,而高水位运行不利于越冬候鸟栖息地的保护,为调和工程效益和候鸟保护之间的矛盾,建议实施适当退田还湖,以促进鄱阳湖水利枢纽工程的规划实施;(2)根据地形、越冬候鸟分布范围、圩堤内居民点分布以及圩堤内土地利用现状,提出了约640km2实施退田还湖范围;(3)以退田还湖为前提,按照"调枯不调洪"原则,提出鄱阳湖水利枢纽工程的水位调控方案,为工程的推进和实施提供参考。

关键词：鄱阳湖水利枢纽退田还湖生态移民越冬候鸟

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赣江流域土地利用方式对河流水质的影响

生态学报 2015年第13期35卷 4326-4337页

作者：王鹏齐述华陈波江西师范大学鄱阳湖湿地与流域研究教育部重点实验室南昌330022 江西省水土保持科学研究院江西省土壤侵蚀与防治重点实验室南昌330029

赣江是鄱阳湖的最大支流,是鄱阳湖水污染物的主要来源,查明流域土地利用方式对赣江水质的影响和鄱阳湖的水环境保护具有重要意义。基于2012年对赣江7个主要支流NH+4-N、TP、CODMn和DO浓度的每月测定结果,通过不同空间尺度和土地类型等... 详细信息

赣江是鄱阳湖的最大支流,是鄱阳湖水污染物的主要来源,查明流域土地利用方式对赣江水质的影响和鄱阳湖的水环境保护具有重要意义。基于2012年对赣江7个主要支流NH+4-N、TP、CODMn和DO浓度的每月测定结果,通过不同空间尺度和土地类型等级划分,利用相关分析和冗余分析研究土地利用方式对赣江流域河流水质的影响。研究结果表明,子流域的土地利用方式对TP的影响大于缓冲区;对CODMn的影响在丰水期大于缓冲区,在枯水期小于缓冲区;对NH+4-N的影响在丰水期与缓冲区接近,在枯水期小于缓冲区;DO受土地利用方式的影响较小。水田中的丘陵水田是赣江水体TP和丰水期CODMn的主要来源;平原水田是枯水期CODMn的主要来源。居民建设用地中的城镇用地是赣江水体TP、NH+4-N和丰水期CODMn的主要来源,农村用地是CODMn的主要来源。水域中的水库坑塘是赣江水体TP和丰水期NH+4-N、CODMn的主要来源。

关键词：赣江河流水质土地利用空间尺度分类等级

硅丙树脂/丙烯酸柱撑LDH纳米复合材料界面研究

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工程塑料应用 2013年第6期41卷 29-32页

作者：赵维齐暑华咸阳师范学院化学与化工学院陕西咸阳712000 西北工业大学理学院西安710072

采用原位聚合法和共混法制备硅丙树脂/丙烯酸柱撑水滑石(AA-LDHs)纳米复合材料,利用X射线衍射分析、扫描电子显微镜对其结构和界面进行表征。结果表明,硅丙树脂与AA-LDHs发生了化学键合;共混型、共聚型材料均为纳米复合材料,其中共聚型... 详细信息

采用原位聚合法和共混法制备硅丙树脂/丙烯酸柱撑水滑石(AA-LDHs)纳米复合材料,利用X射线衍射分析、扫描电子显微镜对其结构和界面进行表征。结果表明,硅丙树脂与AA-LDHs发生了化学键合;共混型、共聚型材料均为纳米复合材料,其中共聚型复合材料中,AA-LDHs片层较均匀地分散于硅丙树脂基体中,且有部分片层发生剥离;通过对其界面研究,发现共混型纳米复合材料相容性较差,界面作用较弱,而共聚型纳米复合材料相容性好,片层与树脂之间结合紧密,明显的相间界面已经消失,界面作用增强,但当AA-LDHs质量分数为4%时,复合材料的脆性增加,韧性降低。

关键词：硅丙树脂原位聚合法纳米复合材料丙烯酸柱撑水滑石界面

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萘酚对环保型酚醛树脂的改性研究

工程塑料应用 2009年第12期37卷 19-21页

作者：张剑齐暑华西北工业大学365所西安710072 西北工业大学理学院应用化学系西安710072

对萘酚改性环保型酚醛树脂(PF)进行了研究,通过差示扫描量热(DSC)、热重分析(TGA)仪和扫描电子显微镜(SEM)等对改性前后PF的耐磨、耐热性能及力学性能进行了对比。结果表明,改性后的PF耐磨性、耐热性和力学性能均比未改性时有很大程度... 详细信息

对萘酚改性环保型酚醛树脂(PF)进行了研究,通过差示扫描量热(DSC)、热重分析(TGA)仪和扫描电子显微镜(SEM)等对改性前后PF的耐磨、耐热性能及力学性能进行了对比。结果表明,改性后的PF耐磨性、耐热性和力学性能均比未改性时有很大程度的提高。萘酚改性的PF可将树脂的质量磨损损失降低54.9%,质量磨损损失率降低56.0%。改性PF的初始失重温度提高70～80℃,可将树脂在600℃时的残余量提高37%。改性后PF的拉伸强度、弯曲强度和冲击强度分别比未改性时提高了519.7、360.4 MPa和43.2 kJ/m^2。

关键词：环保型酚醛树脂萘酚耐磨性耐热性