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Lightweight and High-Performance Microwave Absorber Based on 2D WS2-RGO Heterostructures

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Nano-Micro Letters 2019年第3期11卷 21-35页

作者： Deqing Zhang Tingting Liu Junye Cheng Qi cao guangping Zheng Shuang Liang Hao Wang MaoSheng cao School of Materials Science and Engineering Qiqihar UniversityQiqihar161006People’s Republic of China Guangdong Provincial Key Laboratory of Micro/Nano Optomechatronics Engineering College of Mechatronics and Control EngineeringShenzhen UniversityShenzhen518060People’s Republic of China Department of Chemistry School of ScienceThe University of TokyoTokyo113.8656Japan4Department of Mechanical EngineeringSchool of EngineeringThe University of TokyoTokyo113.8656Japan Department of Mechanical Engineering Hong Kong Polytechnic UniversityHung HomKowloonHong KongPeople’s Republic of China School of Materials Science and Engineering Beijing Institute of TechnologyBeijing100081People’s Republic of China

Two-dimensional(2D)nanomaterials are categorized as a new class of microwave absorption(MA)materials owing to their high specific surface area and peculiar electronic *** this study,2D WS2-reduced graphene oxide(WS2-rGO)heterostructure nanosheets were synthesized via a facile hydrothermal process;moreover,their dielectric and MA properties were reported for the first ***,the maximum reflection loss(RL)of the sample-wax composites containing 40 wt% WS2-rGO was-41.5 dB at a thickness of 2.7 mm;furthermore,the bandwidth where RL<-10 dB can reach up to 13.62 GHz(4.38-18 GHz).Synergistic mechanisms derived from the interfacial dielectric coupling and multiple-interface scattering after hybridization of WS2 with rGO were discussed to explain the drastically enhanced microwave absorption *** results indicate these lightweight WS2-rGO nanosheets to be potential materials for practical electromagnetic wave-absorbing applications.

关键词： 2D WS2 nanosheets Reduced graphene oxide Heterostructure Microwave absorption

红树老鼠簕来源内生青霉 Penicillium *** 03101的次级代谢产物研究

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广西科学 2022年第5期29卷 839-845页

作者：谭玉莹曹广萍黄炯丽李秋庭唐振洲刘永宏高程海白猛广西大学轻工与食品工程学院广西南宁530004 广西中医药大学海洋药物研究院广西南宁530200

为了研究红树老鼠簕Acanthus ilicifolius L.来源内生青霉Penicillium *** 03101的次级代谢产物,采用硅胶柱层析、凝胶柱层析及半制备高效液相色谱对大米发酵产物进行分离纯化,利用核磁共振方法鉴定化合物的结构,并对化合物1-4进行抗胰... 详细信息

为了研究红树老鼠簕Acanthus ilicifolius L.来源内生青霉Penicillium *** 03101的次级代谢产物,采用硅胶柱层析、凝胶柱层析及半制备高效液相色谱对大米发酵产物进行分离纯化,利用核磁共振方法鉴定化合物的结构,并对化合物1-4进行抗胰腺癌活性筛选。结果显示,从内生青霉Penicillium *** 03101中分离鉴定出13个化合物,分别为(+)-rugulosin A(1)、(+)-rugulosin B(2)、1,1′,3,3′,5,5′-hexahydroxy-7,7′-dimethyl[2,2′-bianthracene]-9,9′,10,10′-tetraone(3)、questin(4)、emodin(5)、questinol(6)、uridine(7)、2′-deoxythymidine(8)、5′-O-acetyl uridine(9)、ergosta-5,7,22-triene-3β-ol(10)、(3 R)-6-hydroxymellein(11)、6-hydroxy-8-methoxy-3,4-dimethylisocoumarin(12)和indole-3-acetic acid(13)。其中,化合物1对胰腺癌细胞表现出较好的细胞毒活性,其浓度为10μmol/L时对胰腺癌细胞的抑制率为75.6%。以上结果为进一步研究开发红树内生青霉来源的天然抗胰腺癌药物提供了物质基础。

关键词：红树老鼠簕内生真菌 Penicillium sp. 次级代谢产物抗胰腺癌活性

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山东省粮食生产资源配置现状及其优化研究

山东财经大学学报 2017年第2期29卷 36-44页

作者：曹广平周林宫同瑶季明川杨萍李明辉山东省农业科学院山东种业集团股份有限公司山东济南250100 山东省农业科学院山东济南250100 山东财经大学农业与农村经济研究中心山东济南250014 山东省农业科学院山东省农业可持续发展研究所山东济南250100

采用数据包络分析(DEA)法,通过构建评价体系,测算了山东省17地市粮食生产资源配置效率,并给出了粮食生产要素投入产出的数量优化关系。结果发现:第一,2004-2013年,山东省粮食生产资源配置效率略有改善,但自2008年起呈现下滑态势;同时,... 详细信息

采用数据包络分析(DEA)法,通过构建评价体系,测算了山东省17地市粮食生产资源配置效率,并给出了粮食生产要素投入产出的数量优化关系。结果发现:第一,2004-2013年,山东省粮食生产资源配置效率略有改善,但自2008年起呈现下滑态势;同时,资源配置效率地区差异较为显著。第二,山东省有9个地市存在不同程度的DEA技术无效现象。第三,消除各地区的投入冗余现象可以优化粮食生产要素配置。各地市优化要素配置后,粮食产量将达到1 072亿斤,可以实现全省粮食产量1 000亿斤的既定目标。建议各地市应结合实际,引导农民科学配置粮食生产资源,提升粮食生产率。

关键词：山东省粮食生产资源配置优化

High-performance microwave absorption enabled by Co_(3)O_(4) modified VB-group laminated VS_(2) with frequency modulation from S-band to Ku-band

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Journal of Materials Science & Technology 2022年第12期107卷 155-164页

作者： Zehao Huang Junye Cheng Huibin Zhang Yingfei Xiong Zhanxin Zhou Qingbin Zheng guangping Zheng Deqing Zhang Maosheng cao School of Materials Science and Engineering Qiqihar UniversityQiqihar 161006China Department of Materials Science and Engineering Hong Kong Polytechnic UniversityHung HomKowloonHong KongChina School of Science and Engineering The Chinese University of Hong KongShenzhen 518172China School of Materials Science and Engineering Beijing Institute of TechnologyBeijing 100081China

High performance microwave absorption(MA)materials especially those with tunable frequency are highly desirable for telecommunication industries and military camouflage in the information ***,we constructed hierarchical heterostructures based on VB-group laminated vanadium disulfide(VS_(2))nanosheets embedded with cobalt tetroxide(Co_(3)O_(4))*** highly dispersed Co_(3)O_(4)nanoparticles generate strong electromagnetic coupling networks that could enhance the loss properties of MA ***,the interconnected VS_(2)layered network results in dipolar/interfacial polarization,multiple reflection and scattering favorable for the enhanced MA ***,the maximum reflection loss of the VS_(2)/Co_(3)O_(4)hybrids containing 10%Co_(3)O_(4)can reach 57.96 dB at a thin thickness of 1.57 mm,and the bandwidth with an RL value less than-10 dB is as large as 3.5 *** effective MA band could be adjusted in a range of 15.1 GHz(2.9-18 GHz)from S to Ku bands by the increase in thickness from 1.2 mm to 5.5 *** results show that the synergistic effect of multiple loss mechanisms and good impedance matching could be the reasons for strong MA capability in nearly all frequency bands,and thus,the high-performance and lightweight MA materials could be developed by the VS_(2)/Co_(3)O_(4)hybrids.

关键词： VS2 nanosheets Co_(3)O_(4)nanospheres Hetero-structure Microwave wave absorption

Building the conformal protection of VB-group VS_(2)laminated heterostructure based on biomass-derived carbon for excellent broadband electromagnetic waves absorption

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Journal of Materiomics 2023年第3期9卷 492-501页

作者： Honghan Wang Huibin Zhang Junye Cheng Tingting Liu Deqing Zhang guangping Zheng Shangru Zhai Maosheng cao School of Materials Science and Engineering Qiqihar UniversityQiqihar161006China Liaoning Key Lab of Lignocellulose Chemistry and BioMaterials Liaoning Collaborative Innovation Center for Lignocellulosic BiorefineryCollege of Light Industry and Chemical EngineeringDalian Polytechnic UniversityDalian116034China Department of Materials Science Shenzhen MSU-BIT UniversityShenzhenGuangdong Province517182China School of Materials Science and Engineering Beijing Institute of TechnologyBeijing100081China Department of Mechanical Engineering Hong Kong Polytechnic UniversityHung HomKowloonHong KongChina

Although VB-Group transition metal disulfides(TMDs)VS_(2)nanomaterials with specific electronic properties and multiphase microstructures have shown fascinating potential in the field of electro-magnetic wave(EMW)absorption,the efficient utilization of VS_(2)is limited by the technical bottleneck of its narrow effective absorption bandwidth(EAB)which is attributed to environmental instability and a deficient electromagnetic(EM)loss *** order to fully exploit the maximal utilization values of VS_(2)nanomaterials for EMW absorption through mitigating the chemical instability and optimizing the EM parameters,biomass-based glucose derived carbon(GDC)like sugar-coating has been decorated on the surface of stacked VS_(2)nanosheets via a facile hydrothermal method,followed by high-temperature *** a result,the modulation of doping amount of glucose injection solution(Glucose)could effectively manipulate the encapsulation degree of GDC coating on VS_(2)nanosheets,further imple-menting the EM response mechanisms of the VS_(2)/GDC hybrids(coupling effect of conductive loss,interfacial polarization,relaxation,dipole polarization,defect engineering and multiple reflections and absorptions)through regulating the conductivity and constructing multi-interface heterostructures,as reflected by the enhanced EMW absorption performance to a great *** minimum reflection loss(Rmin)of VS_(2)/GDC hybrids could reach52.8 dB with a thickness of 2.7 mm at 12.2 ***,compared with pristine VS_(2),the EAB of the VS_(2)/GDC hybrids increased from 2.0 to 5.7 GHz,while their environmental stability was effectively enhanced by virtue of GDC ***,this work provides a promising candidate to realize frequency band tunability of EMW absorbers with exceptional perfor-mance and environmental stability.

关键词： VS_(2)/GDC hybrids Multi-interface heterostructures Broadband absorption Environmental stability

Classification and applied uses of Bryaceae sensu lato(Musci) in China

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科学通报 2013年第S1期58卷 29-34页

作者： ZHAO JianCheng LIU YongYing cao Zhen FENG guangping NIU YuLu College of Life Science Hebei Normal University Department of Biology Jiaozuo Teachers College Hebei Women’s Vocational College Beijing Museum of Natural History College of Life Science Hengshui University

The Bryaceae is a large, cosmopolitan, taxonomically difficult moss family. Recent studies based on molecular data alone or in combination with morphological data have greatly changed the understanding of phylogenetic relationships in the Bryaceae s.l. and indicate that the Bryaceae is not monophyletic. Based on phylogenetic analyses of sequence data for four cpDNA regions and morphological data, we revise the traditional Bryaceae in China and transfer six genera to other families. The Mielichhoferiaceae was redefined previously by Hill et al. based on the presence of much-branched stems, apparently lateral gametangia, Pohlia-like leaves, and a more-or-less reduced peristome. Five genera of Mielichhoferiaceae are present in China: Mielichhoferia(four species), Pohlia(27 species, two varieties), Pseudopohlia(one species), Epipterygium(two species), and Synthetodontium(one species). The genera Orthodontium and Leptobryum are transferred from the Bryaceae s.l. to Orthodontiaceae and Meesiaceae, respectively. Members of the recircumscribed Bryaceae belong to five genera: Anomobryum(five species), Brachymenium(14 species), Bryum(54 species, two varieties), Plagiobryum(three species), and Rhodobryum(four species). Bryaceae diversity is high in China. The species have potential uses in medicine, landscaping, environmental protection, and other fields. Rhodobryum roseum(Hedw.) Limpr., Bryum argenteum Hedw., and Rhodobryum giganteum(Schw gr.) Paris have long been used to cure cardiovascular disease in China. Some bioactive compounds will be leading compounds for the future design of novel drugs. In recent years, many species of Bryaceae have been used for landscaping. Bryum spp. are the dominant biotic species in biological soil crusts, which serve important ecological protective functions.

关键词： classification ecological protection landscaping medicinal value Bryaceae sensu lato

Recent Advances in Design Strategies and Multifunctionality of Flexible Electromagnetic Interference Shielding Materials

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Nano-Micro Letters 2022年第5期14卷 122-152页

作者： Junye Cheng Chuanbing Li Yingfei Xiong Huibin Zhang Hassan Raza Sana Ullah Jinyi Wu guangping Zheng Qi cao Deqing Zhang Qingbin Zheng Renchao Che School of Science and Engineering The Chinese University of Hong KongShenzhen 518172People’s Republic of China School of Materials Science and Engineering Qiqihar UniversityQiqihar 161006People’s Republic of China Laboratory of Advanced Materials Shanghai Key Lab of Molecular Catalysis and Innovative MaterialsDepartment of Materials ScienceFudan UniversityShanghai 200438People’s Republic of China Department of Mechanical Engineering Hong Kong Polytechnic UniversityHung HomKowloonHong KongPeople’s Republic of China Key Laboratory of Energy Thermal Conversion and Control of Ministry of Education School of Energy and EnvironmentSoutheast UniversityNanjing 210096People’s Republic of China

With rapid development of 5G communication technologies,electromagnetic interference(EMI)shielding for electronic devices has become an urgent demand in recent years,where the development of corresponding EMI shielding materials against detrimental electromagnetic radiation plays an essential ***,the EMI shielding materials with high flexibility and functional integrity are highly demanded for emerging shielding ***,a variety of flexible EMI shielding materials with lightweight and multifunctionalities have been *** this review,we not only introduce the recent development of flexible EMI shielding materials,but also elaborate the EMI shielding mechanisms and the index for"green EMI shielding"*** addition,the construction strategies for sophisticated multifunctionalities of flexible shielding materials are ***,we propose several possible research directions for flexible EMI shielding materials in near future,which could be inspirational to the fast-growing next-generation flexible electronic devices with reliable and multipurpose protections as offered by EMI shielding materials.

关键词： Flexible shielding materials Green shielding index Multifunctionalities EMI shielding mechanism

Engineering flexible and green electromagnetic interference shielding materials with high performance through modulating WS_(2) nanosheets on carbon fibers

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Journal of Materiomics 2022年第2期8卷 327-334页

作者： Huibin Zhang Tingting Liu Zehao Huang Junye Cheng Honghan Wang Deqing Zhang Xuewei Ba guangping Zheng Ming Yan Maosheng cao School of Materials Science and Engineering Qiqihar UniversityQiqihar 161006China Department of Mechanical Engineering Hong Kong Polytechnic UniversityHung HomKowloonHong KongChina Department of Materials Science and Engineering And Shenzhen Key Laboratory for Additive Manufacturing of High-performance MaterialsSouthern University of Science and TechnologyShenzhen 518055China School of Materials Science and Engineering Beijing Institute of TechnologyBeijing 100081China

Flexible and wearable electromagnetic interference(EMI)shielding material is one of the current research focuses in the field of EMI *** this work,for the first time,WS_(2)-carbon fiber(WS_(2)-CF)composites are synthesized by implanting WS_(2),which has a multiphase structure and a large number of defects,onto the surface of carbon fiber(CF)by using a simple one-step hydrothermal method,and are applied to protect electronic devices from *** is found that the EMI shielding performance of WS_(2)-CF is significantly improved,especially for those at Se and *** 2 GHz,the EMI shielding efficiency could reach 36.0 dB at a typical thickness of 3.00 mm of the composite,which is much better than that of pure CF(25.5 dB).Besides paving a novel avenue to optimize the electromagnetic shielding performance of flexible and wearable CF-based EMI shielding materials,which have great potential in the practical application for EMI shielding,this work provides a new paradigm for the design and synthesis of EMI shielding materials which have a broad application prospect.

关键词： Flexible electromagneic shielding Carbon fibers WS_(2) Conductive networks

Effect of Various Alumina Powders on Properties of Castables

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China's Refractories 2022年第2期31卷 45-48页

作者： SONG Yanan WEI Guoping CHEN Qin SHUAI Hang LIU guangping SHEN Mingke CHEN Yaosheng YU Yan WANG Yulong cao Yaping Zhejiang Zili Advanced Materials Co. Ltd.Shaoxing 312300China Zhejiang Zili High Temperature Technology Co. Ltd.Shaoxing 312300China

To satisfy the requirements of alumina castables in specific environment and enhance their properties,alumina castables were prepared using tabular alumina,various alumina powders(07RAL,15RA,22RABL,40CA,99-20um,and 99-325mesh),and calcium aluminate cement as main raw materials,and heat treating at 110,1000,1600℃,*** flowability and physical properties were tested,and the morphology was *** results show that compared with calcined alumina and tabular alumina powders,reactive alumina has higher specific surface area and better filling performance leading to lower water demand and higher viscosity,and the castables prepared with reactive alumina have higher CCS and CMOR after heat treating at 110,1000 and 1600℃as well as lower PLC than those with calcined alumina and tabular alumina powders.

关键词： alumina powder castables rheological property construction time sintering performance