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The development of advanced Cr-free organic composite coated electrogalvanized steel sheet with excellent grounding property
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作者 ZHANG Jianping Research Institute,Baoshan Iron & Steel Co.,Ltd.,Shanghai 201900,China 《Baosteel Technical Research》 CAS 2010年第S1期43-,共1页
In recent years,the concern about environmental protection is increasing on a world scale.Major manufacturers of home appliances and OA equipment have introduced so-called 'green procurement schemes' for reduc... In recent years,the concern about environmental protection is increasing on a world scale.Major manufacturers of home appliances and OA equipment have introduced so-called 'green procurement schemes' for reducing environmentally harmful substances in manufacturing process and end products. Under such background,a new type of chromate-free organic composite coated electro-galvanized steel sheet with high conductivity was developed by Baosteel,which meets the EU RoHS Directive(Restriction of the Hazardous Substances) and other related laws and regulations on environmental safety.It also provides excellent surface electrical conductivity,corrosion resistance,fingerprint resistance,solvent resistance,coating adhesion, heat resistance,formability and other special properties to meet the demand of manufacture's process of OA machine. Compared with previously developed anti-fingerprinting coated electro-galvanized steel sheet,this newly developed product has a good balance between high corrosion resistance(time to 5%white rust in salt spray test is 120 h for flat panel and 72 h for worked potion) and conductivity(surface electro-resistivity in accordance with LOREAST is less than 0.1 milliohm ) due to the special design of coating's structure.Besides,It also provides the properties of grounding and shielding against electromagnetic waves.The evaluation of surface performances of new product showed that it is comparable or even better than the similar products. Currently,the newly developed product has been commercialized. In this paper,the major properties are discussed,such as corrosion resistance,surface electrical conductivity, fingerprint resistance,solvent resistance,coating adhesion(ink/melamine alkyd paint),heat resistance and formability.Furthermore,the application is also briefly described. 展开更多
关键词 chromate-free thin organic composite coating conductivity corrosion resistance elecro-galvanized steel sheet
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Natural forests exhibit higher organic carbon concentrations and recalcitrant carbon proportions in soil than plantations:a global data synthesis
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作者 Xiuqing Nie Hui Wang +1 位作者 Jian Wang Shirong Liu 《Journal of Forestry Research》 SCIE EI CAS CSCD 2024年第5期131-141,共11页
Different chemical compositions of soil organic carbon(SOC)affect its persistence and whether it signifi-cantly differs between natural forests and plantations remains unclear.By synthesizing 234 observations of SOC c... Different chemical compositions of soil organic carbon(SOC)affect its persistence and whether it signifi-cantly differs between natural forests and plantations remains unclear.By synthesizing 234 observations of SOC chemical compositions,we evaluated global patterns of concentra-tion,individual chemical composition(alkyl C,O-alkyl C,aromatic C,and carbonyl C),and their distribution even-ness.Our results indicate a notably higher SOC,a markedly larger proportion of recalcitrant alkyl C,and lower easily decomposed carbonyl C proportion in natural forests.How-ever,SOC chemical compositions were appreciably more evenly distributed in plantations.Based on the assumed con-ceptual index of SOC chemical composition evenness,we deduced that,compared to natural forests,plantations may have higher possible resistance to SOC decomposition under disturbances.In tropical regions,SOC levels,recalcitrant SOC chemical composition,and their distributed evenness were significantly higher in natural forests,indicating that SOC has higher chemical stability and possible resistance to decomposition.Climate factors had minor effects on alkyl C in forests globally,while they notably affected SOC chemi-cal composition in tropical forests.This could contribute to the differences in chemical compositions and their distrib-uted evenness between plantations and natural stands. 展开更多
关键词 Global data synthesis Natural forest Plantations Soil organic carbon Soil organic carbon chemical composition
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Organic composite materials:Understanding and manipulating excited states toward higher light-emitting performance 被引量:2
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作者 Haiyun Dong Chunhuan Zhang +1 位作者 Jiannian Yao Yong Sheng Zhao 《Aggregate》 2021年第4期31-42,共12页
Organic composite materials have been attracting extensive research interest for light-emitting applications.A wide variety of luminescent organic composite materials have been synthesized,which are of great significa... Organic composite materials have been attracting extensive research interest for light-emitting applications.A wide variety of luminescent organic composite materials have been synthesized,which are of great significance for both the investigation of basic photophysics and the realization of high-performance photonic devices.Function-oriented syntheses of luminescent organic composite materials rely on the understanding and manipulating of molecular excited states.In this review,we focus on the discussion about the structure design and dynamics modulation of the electronic excited states in the organic composite materials.The excited-state structures and dynamics involve singlet/triplet levels,vibronic transition,charge transfer,and energy transfer,and so on,while the light-emitting behaviors include fluorescence,phosphorescence,persistent luminescence,electroluminescence,and lasing.We aim to give insight into the relationship between light-emitting properties and excited states of organic composite materials,which is beneficial for reaching higher tiers of design and applications of luminescent organic composite materials. 展开更多
关键词 excited states molecular optoelectronics organic composite materials organic lasers organic lightemitting materials
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Increased performance of an organic light-emitting diode by employing a zinc phthalocyanine based composite hole transport layer
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作者 郭闰达 岳守振 +3 位作者 王鹏 陈宇 赵毅 刘式墉 《Chinese Physics B》 SCIE EI CAS CSCD 2013年第12期431-434,共4页
We demonstrate that the electroluminescent performances of organic light-emitting diodes are significantly improved by employing a zinc phthalocyanine (ZnPc)-based composite hole transport layer (c-HTL). The optim... We demonstrate that the electroluminescent performances of organic light-emitting diodes are significantly improved by employing a zinc phthalocyanine (ZnPc)-based composite hole transport layer (c-HTL). The optimum ris-(8-hydroxyquinoline)aluminum (Alq3)-based organic light-emitting diode with a c-HTL exhibits a lower turn-on voltage of 2.8 V, a higher maximum current efficiency of 3.40 cd/A and a higher maximum power efficiency of 1.91 lm/W, which are superior to those of the conventional device (turn-on voltage of 3.8 V, maximum current efficiency of 2.60 cd/A, and maximum power efficiency of 1.21 lm/W). We systematically studied the effects of different kinds of N’-diphenyl-N,N’-bis(1-naphthyl)(1,1’-biphenyl)-4,4’diamine (NPB):ZnPc c-HTL. Meanwhile, we also investigate their mechanisms different from that in the case of using ZnPc as buffer layer. The specific analysis is based on the absorption spectra of the hole transporting material and current density–voltage characteristics of the corresponding hole-only devices. 展开更多
关键词 organic light emitting diodes composite hole transport layer zinc phthalocyanine
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Effect of organic binders on the activation and properties of indurated magnetite pellets 被引量:4
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作者 Cui Wang Chen-yang Xu +3 位作者 Zheng-jian Liu Yao-zu Wang Rong-rong Wang Li-ming Ma 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2021年第7期1145-1152,共8页
In the ironmaking process,the addition of an organic binder to replace a portion of bentonite has the potential to improve the per-formance of pellets.The interaction between original bentonite(OB)and organic binder w... In the ironmaking process,the addition of an organic binder to replace a portion of bentonite has the potential to improve the per-formance of pellets.The interaction between original bentonite(OB)and organic binder was investigated.Results indicated that the micromor-phology of organic composite bentonite(OCB)became porous and the infrared difference spectrum exhibited a curved shape.In addition,the residual burning rates of OB and organic binder were determined to be 82.72%and 2.30%,respectively.Finally,the influence of OCB on the properties of pellets was investigated.The compressive strength of OCB-added green pellets(14.7 N per pellet)was better than that of OB-ad-ded pellets(10.3 N per pellet).Moreover,the range of melting temperature of OCB-added green pellets(173℃)was narrower than that of OB-added pellets(198℃).The compressive strength of OCB-added green pellets increased from 2156 to 3156 N per pellet with the increase in roasting temperature from 1200 to 1250℃. 展开更多
关键词 PELLETS organic composite bentonite softening-melting property interaction behavior
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Ag nanoparticles anchored organic/inorganic Z‐scheme 3DOMM‐TiO_(2‒x)‐based heterojunction for efficient photocatalytic and photoelectrochemical water splitting 被引量:1
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作者 Zhiying Xu Chunyu Guo +7 位作者 Xin Liu Ling Li Liang Wang Haolan Xu Dongke Zhang Chunhu Li Qin Li Wentai Wang 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 2022年第5期1360-1370,共11页
Narrow spectral response,low charge separation efficiency and slow water oxidation kinetics of TiO_(2)limit its application in photoelectrochemical and photocatalytic water splitting.Herein,a promising organic/inorgan... Narrow spectral response,low charge separation efficiency and slow water oxidation kinetics of TiO_(2)limit its application in photoelectrochemical and photocatalytic water splitting.Herein,a promising organic/inorganic composite catalyst Ag/PANI/3DOMM‐TiO_(2–x)with a three‐dimensional ordered macro‐and meso‐porous(3DO MM)structure,oxygen vacancy and Ti^(3+)defects,heterojunction formation and noble metal Ag was designed based on the Z‐scheme mechanism and successfully prepared.The Ag/PANI/3DOMM‐TiO_(2–x)ternary catalyst exhibited enhanced hydrogen production activity in both photocatalytic and photoelectrochemical water splitting.The photocatalytic hydrogen production rate is 420.90μmol g^(–1)h^(–1),which are 19.80 times and 2.06 times higher than the commercial P25 and 3DOMM‐TiO_(2),respectively.In the photoelectrochemical tests,the Ag/PANI/3DOMM‐TiO_(2–x)photoelectrode shows enhanced separation and transfer of carriers with a high current density of 1.55 mA cm^(–2)at equilibrium potential of 1.23 V under simulated AM 1.5 G illumination,which is approximately 5 times greater than the 3DOMM‐TiO_(2).The present work has demonstrated the promising potential of organic/inorganic Z‐scheme photocatalyst in driving water splitting for hydrogen production. 展开更多
关键词 PHOTOELECTROCHEMICAL PHOTOCATALYSIS organic/inorganic composite HETEROJUNCTION Water splitting
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Organic Carbon Isotope Geochemistry of the Neoproterozoic Doushantuo Formation,South China 被引量:3
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作者 GUO Qingjun LIU Congqiang +4 位作者 Harald STRAUSS Tatiana GOLDBERG ZHU Maoyan PI Daohui WANG Jian 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2006年第5期670-683,共14页
The Neoproterozoic Doushantuo Formation on the Yangtze Platform, South China, documents a sedimentary succession with different sedimentary facies from carbonate platform to slope and to deep sea basin, and hosts one ... The Neoproterozoic Doushantuo Formation on the Yangtze Platform, South China, documents a sedimentary succession with different sedimentary facies from carbonate platform to slope and to deep sea basin, and hosts one of the world-class phosphorite deposits. In these strata, exquisitely preserved fossils have been discovered: the Weng'an biota. This study presents carbon isotope geochemistry which is associated paired carbonate and organic matter from the Weng'an section of a carbonate platform (shelf of the Yangtze Platform, Guizhou Province) from the Songtao section and Nanming section of a transition belt (slope of the Yangtze Platform, Guizhou Province) and from the Yanwutan section (basin area of the Yangtze Platform, Hunan Province). Environmental variations and bio-events on the Yangtze Platform during the Late Neoproterozoic and their causal relationship are discussed. Negative carbon isotope values for carbonate and organic carbon (mean δ^13Corg = -35.0‰) from the uppermost Nantuo Formation are followed by an overall increase in δ^13C up-section. Carbon isotope values vary between -9.9‰ and 3.6‰ for carbonate and between -35.6‰ and -21.5‰ for organic carbon, respectively. Heavier δ^13Ccarb values suggest an increase in organic carbon burial, possibly related to increasing productivity (such as the Weng'an biota). The δ^13C values of the sediments from the Doushantuo Formation decreased from the platform via the slope to basin, reflecting a reduced environment with minor dissolved inorganic carbon possibly due to a lower primary productivity. It is deduced that the classical upwelling process, the stratification structure and the hydrothermal eruption are principally important mechanisms to interpret the carbon isotopic compositions of the sediments from the Doushantuo Formation. 展开更多
关键词 Late Neoproterozoic Doushantuo Formation organic carbon isotopic composition the Yangtze Platform
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Microstructure and Characterization of Capric-stearic Acid/Modified Expanded Vermiculite Thermal Storage Composites 被引量:1
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作者 刘凤利 朱教群 +4 位作者 LIU Junhua MA Baoguo ZHOU Weibing LI Ruguang QIN Weigao 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2018年第2期296-304,共9页
In order to improve the thermal storage capacity of expanded vermiculite(EV) based formstable composite PCM(FS-PCM) via organic modification of EV, first, EV was modified with a sodium stearate(Na St) as surface... In order to improve the thermal storage capacity of expanded vermiculite(EV) based formstable composite PCM(FS-PCM) via organic modification of EV, first, EV was modified with a sodium stearate(Na St) as surface modifier, and organic EV(OEV) with hydrophobicity and higher adsorption capacity for fatty acid was obtained. A novel capric-stearic acid eutectic(CA-SA)/OEV FS-PCM with high thermal storage capacity was then developed. OEV and CA-SA/OEV were characterized by scanning electron microscopy(SEM), X-ray diffraction(XRD), Fourier transform infrared spectroscopy(FTIR), differential scanning calorimetry(DSC), thermal gravimetry(TG), and thermal cycling test. Results showed that OEV has obvious hydrophobicity and a higher adsorption capacity for fatty acid. Its adsorption ratio has increased by 48.71% compared with that of EV. CA-SA/OEV possesses high thermal storage density(112.52 J/g), suitable melting temperature(20.49 ℃), good chemical compatibility, excellent thermal stability and reliability, indicating great application potential for building energy efficiency. Moreover, organic modification of inorganic matrix may offer novel options for improving its adsorption capacity for organic PCMs and increasing heat storage capacity of corresponding FS-PCMs. 展开更多
关键词 organic expanded vermiculite capric-stearic acid eutectic form-stable composite PCMs thermal energy storage building envelope
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Carbon Isotopic Evolution of the Late Ediacaran Gaojiashan Biota on the Northern Yangtze Platform,South China 被引量:2
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作者 GUO Qingjun DENG Yinan YANG Xinglian 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2012年第6期1447-1454,共8页
Metazoan fossils in the Gaojiashan Biota are famous for being well preserved and may provide new insights into the early evolution and skeletonization of Metazoans. We are studying the isotopic compositions of organic... Metazoan fossils in the Gaojiashan Biota are famous for being well preserved and may provide new insights into the early evolution and skeletonization of Metazoans. We are studying the isotopic compositions of organic and carbonate carbon from a sequence of sedimentary rocks at the Gaojiashan section, northern Yangtze Platform, Shaanxi Province of China. Organic carbon isotope values display a range between -30.8%0 and -24.7%0 with clear stratigraphic variations. Carbonate carbon isotope data vary between 0.1%o and +6%0. Positive j13C values from sediments with Gaojiashan biota reflect temporal variations in carbon turnover, i.e. an increasing in photosynthetic carbon fixation followed by an increasing subsequent fractional organic carbon burial, and that related to bio- radiation such as increasing algae, bacteria, and original creatures productivity in biomass. These secular variations are interpreted to reflect perturbations of the regional carbon cycle, specifically changes in the fractional burial of organic carbon, and discuss the relationship between Gaojiashan biota and paleoenvrionmental variation. 展开更多
关键词 EDIACARAN carbonate and organic carbon isotopic composition Gaojiashan biota Ningqiang Yangtze Platform
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Photocatalytic degradation of tetracycline hydrochloride with visible light-responsive bismuth tungstate/conjugated microporous polymer 被引量:1
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作者 Fenghongkang Pan Yimeng Wang +3 位作者 Kaiqing Zhao Jun Hu Honglai Liu Ying Hu 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2022年第1期488-496,共9页
Conjugated microporous polymer(CMP)is an emerging organic semiconductor withπ-conjugated skeletons,and the bandgap of CMP can be flexibly modulated to harvest visible light.Based on the diversity and adjustability of... Conjugated microporous polymer(CMP)is an emerging organic semiconductor withπ-conjugated skeletons,and the bandgap of CMP can be flexibly modulated to harvest visible light.Based on the diversity and adjustability of monomers in CMP,we designed and synthesized donor-accepter(D-A)type BTNCMP through Sonogashira-Hagihara cross-coupling polymerization,further in-situ constructing series of inorganic/organic Z-scheme BW/BTN-n composite in the presence of Bi_(2)WO_(6).After optimization,the tetracycline hydrochloride(C0=10 mg·L^(-1))degradation efficiency reached 84%with BW/BTN-2 as catalyst in 90 min under visible light irradiation,the apparent rate constant k1 is 0.017 min^(-1),which is 1.7 and 5.7 times higher than bare Bi_(2)WO_(6) and BTN-CMP.X-ray photoelectron spectra and UV-Vis diffuse spectra showed that the enhanced photocatalytic activity originated from the tight heterojunction between Bi_(2)WO_(6) and BTN-CMP,which can extend the light absorption range and facilitate the separation and transport of photogenerated charges in the interface of heterojunction.The active species trapping experiments and electron spin resonance technique revealed that h+was the dominant active species during the photodegradation process of tetracycline hydrochloride(TCH).The present study demonstrated the feasibility to construct inorganic/organic composite for the photocatalytic degradation of environmental pollutants. 展开更多
关键词 PHOTOCHEMISTRY Degradation Visible light response Pollution Inorganic/organic heterojunction composite
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Low-dimensional cobalt doped carbon composite towards wideband electromagnetic dissipation 被引量:1
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作者 Xiaodi Zhou Biao Zhao Hualiang Lv 《Nano Research》 SCIE EI CSCD 2023年第1期70-79,共10页
Composites composed of a carbon matrix decorated with a metal or metal oxide derived from zeolitic imidazolate frameworks(ZIFs)have been widely applied as suitable electromagnetic wave absorbers due to their high poro... Composites composed of a carbon matrix decorated with a metal or metal oxide derived from zeolitic imidazolate frameworks(ZIFs)have been widely applied as suitable electromagnetic wave absorbers due to their high porosity and controllable morphology.However,achieving ideal absorption performance remains a challenge owing to the inadequate conductivity and high density of the metal components.Therefore,a temperature-controlling treatment was employed for the bimetal ZIFs,and the corresponding derivatives exhibited an excellent dissipation ability with a minimum reflection loss value of−54.3 dB and an effective bandwidth of 7.0 GHz at a thickness of 2.4 mm,which resulted from the strong dipole polarization behavior.Furthermore,after successfully controlling the Zn/Co ratio,the attenuation capability was greatly enhanced at a thickness of 1.4 mm,with bandwidths of 13.0–18.0 GHz.Overall,this work provides an ameliorated strategy for microwave absorption performance of carbon-based materials. 展开更多
关键词 microwave absorption bi-meta based absorber SINGLE-ATOM metal organic frameworks(MOFs)derived composite dielectric relaxation
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Research progress on the origin traceability of edible oils
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作者 Qian Zhou Xinjing Dou +4 位作者 Liangxiao Zhang Wei Fan Shiyin Guo Weiguo Wu Zhonghai Tang 《Oil Crop Science》 2020年第4期194-197,共4页
The origin traceability of edible oil is an effective way to protect the legitimate rights and interests of producers and consumers.This review briefly summarizes research progress on origin traceability technologies ... The origin traceability of edible oil is an effective way to protect the legitimate rights and interests of producers and consumers.This review briefly summarizes research progress on origin traceability technologies for edible oils including stable isotope ratio mass spectrometry,mineral element fingerprint analysis,organic component fingerprint analysis,near-infrared spectroscopy,nuclear magnetic resonance technology and biochemical analysis.Moreover,the development trends in edible oil origin traceability technology were proposed. 展开更多
关键词 Edible oil Origin traceability Stable isotope ratio Mineral element fingerprint organic composition
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Long-range ordering of composites for organic electronics:TIPS-pentacene single crystals with incorporated nano-fibers
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作者 Huanbin Li Guobiao Xue +7 位作者 Jiake Wu Wenqiang Zhang Zhuoting Huang Zengqi Xie Huolin L.Xin Gang Wu Hongzheng Chen Hanying Li 《Chinese Chemical Letters》 SCIE CAS CSCD 2017年第11期2121-2124,共4页
Multi-component active materials are widely used for organic electronic devices, with every component contributing complementary and synergistic optoelectronic functions. Mixing these components generally leads to low... Multi-component active materials are widely used for organic electronic devices, with every component contributing complementary and synergistic optoelectronic functions. Mixing these components generally leads to lowered crystallinity and weakened charge transport. Therefore, preparing the active materials without substantially disrupting the crystalline lattice is highly desired. Here, we show that crystallization of TIPS-pentacene from solutions in the presence of fluorescent nanofibers of a perylene bisimide derivative (PBI) leads to formation of composites with nanoflber guest incorporated in the crystal host. In spite of the binary composite structure, the TIPS-pentacene maintains the single- crystalline nature. As a result, the incorporation of the PB1 guest introduces additional fluorescence function but does not significantly reduce the charge transport property of the TIPS-pentacene host, exhibiting field-effect mobility as high as 3.34 cm^2 V^-1 s^-1 even though 26.4% of the channel area is taken over by the guest. As such, this work provides a facile approach toward high-performance multifunctional organic electronic materials. 展开更多
关键词 organic Electronics Single Crystals composites High Mobility Field-Effect Transistors
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Two-dimensional CuO nanosheets-induced MOF composites and derivatives for dendrite-free zinc-ion batteries
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作者 Guoqiang Yuan Yang-Yi Liu +7 位作者 Jun Xia Yichun Su Wenxian Wei YinBo Zhu Yang An HengAn Wu Qiang Xu Huan Pang 《Nano Research》 SCIE EI CSCD 2023年第5期6881-6889,共9页
Uncontrollable dendrite growth and side reactions resulting in short operating life and low Coulombic efficiency have severely hindered the further development of aqueous zinc-ion batteries(AZIBs).In this work,we desi... Uncontrollable dendrite growth and side reactions resulting in short operating life and low Coulombic efficiency have severely hindered the further development of aqueous zinc-ion batteries(AZIBs).In this work,we designed to grow zeolitic imidazolate framework-8(ZIF-8)uniformly on CuO nanosheets(NSs)and prepared carbon-coated CuZn alloy NSs(CuZn@C NSs)by calcination under H_(2)/Ar atmosphere.As reflected by extended X-ray absorption fine structure(EXAFS),density functional theory(DFT),in-situ Raman,the Cu–Zn and Zn–N bonds present in CuZn@C NSs act as zincophilic sites to uniformly absorb Zn ions and inhibit the formation of Zn dendrites.At the same time,CuZn@C NSs hinder the direct contact between zinc anode and electrolyte,preventing the occurrence of side reactions.More impressively,the symmetric cells constructed with CuZn@C NSs anodes exhibited excellent zinc plating/exfoliation performance and long life cycle at different current densities with low voltage hysteresis.In addition,low polarization,high capacity retention,long cycle life over 1000 cycles at 5 A∙g^(−1) were achieved when CuZn@C NSs were used as anodes for CuZn@C/V_(2)O_(5)full cells. 展开更多
关键词 two-dimensional CuO nanosheet metal–organic frameworks(MOFs)-based composites carbon-coated CuZn alloy nanosheets dendrite-free zinc-ion battery
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Poly(lactic-co-glycolic acid)-based composite bone-substitute materials 被引量:22
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作者 Duoyi Zhao Tongtong Zhu +4 位作者 Jie Li Liguo Cui Zhiyu Zhang Xiuli Zhuang Jianxun Ding 《Bioactive Materials》 SCIE 2021年第2期346-360,共15页
Research and development of the ideal artificial bone-substitute materials to replace autologous and allogeneic bones for repairing bone defects is still a challenge in clinical orthopedics.Recently,poly(lactic-co-gly... Research and development of the ideal artificial bone-substitute materials to replace autologous and allogeneic bones for repairing bone defects is still a challenge in clinical orthopedics.Recently,poly(lactic-co-glycolic acid)(PLGA)-based artificial bone-substitute materials are attracting increasing attention as the benefit of their suitable biocompatibility,degradability,mechanical properties,and capabilities to promote bone regeneration.In this article,we comprehensively review the artificial bone-substitute materials made from PLGA or the composites of PLGA and other organic and inorganic substances,elaborate on their applications for bone regeneration with or without bioactive factors,and prospect the challenges and opportunities in clinical bone regeneration. 展开更多
关键词 Poly(lactic-co-glycolic acid) composite organic−inorganic biomaterial Bone-substitute material Bone tissue engineering Bone regeneration
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Redistribution of Soil Organic Carbon Triggered by Erosion at Field Scale Under Subhumid Climate,Hungary
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作者 Zoltan SZALAI Judit SZABO +7 位作者 Jozsef KOVACS Erzsebet MESZAROS Gaspar ALBERT Csaba CENTERI Boglarka SZABO Balazs MADARASZ Dora ZACHARY Gergely JAKAB 《Pedosphere》 SCIE CAS CSCD 2016年第5期652-665,共14页
Soil organic carbon(SOC) has primary importance in terms of soil physics, soil fertility and even of climate change control. One hundred soil samples were taken from an intensively cultivated Cambisol to quantify SOC ... Soil organic carbon(SOC) has primary importance in terms of soil physics, soil fertility and even of climate change control. One hundred soil samples were taken from an intensively cultivated Cambisol to quantify SOC redistribution triggered by soil erosion under a subhumid climate, by the simultaneous application of diffuse reflectance(240–1 900 nm) and traditional physico-chemical methods.The representative sample points were collected from the solum along the slopes at the depth of 20–300 cm with a mean SOC content of 12 g kg^(-1). Hierarchical cluster analyses were performed based on the determined SOC results. The spatial pattern of the groups created were similar, and even though the classifications were not the same, diffuse reflectance had proven to be a suitable method for soil/sediment classification even within a given arable field. Both organic and inorganic carbon distributions were found to be a proper tool for estimations of past soil erosion processes. The SOC enrichment was found on two sedimentary spots with different geomorphological positions. Soil organic matter composition also differed between the two spots due to selective deposition of the delivered organic matter. The components with low-molecular-weight reached the bottom of the slope where they could leach into the profile, while the more polymerised organic matter compositions were delivered and deposited even before on a higher segment of the slope in an aggregated form. This spatial difference appeared below the uppermost tilled soil layer as well, referring the lower efficiency of conventional ploughing tillage in soil spatial homogenisation. 展开更多
关键词 CAMBISOL carbon sequestration diffuse reflectance selective erosion soil organic matter composition
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On the effect of Fe(Ⅲ) on proliferation of Microcystis aeruginosa at high nitrate and low chlorophyll condition 被引量:4
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作者 Rong Chen Zhen Lei +5 位作者 Jiayuan Ji Xiaochang Wang Yu-You Li Yuan Yang Lu Zhang Tao Xue 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2017年第2期105-110,共6页
The impact of Fe concentrations on the growth of Microcystis aeruginosa in aquatic systems under high nitrate and low chlorophyll conditions was studied. The responses of cell density,total and cell chlorophyll-a intr... The impact of Fe concentrations on the growth of Microcystis aeruginosa in aquatic systems under high nitrate and low chlorophyll conditions was studied. The responses of cell density,total and cell chlorophyll-a intracellular Fe content and organic elemental composition of M.aeruginosa to different concentration gradients of Fe(Ⅲ) in the solutions were analysed. The results showed that the proliferation speeds of M. aeruginosa were:(1) decelerated when the Fe(Ⅲ) concentration was lower than 50 μg/L in the solutions,(2) promoted and positively related to the increase of Fe(Ⅲ) concentration from 100 to 500 μg/L in the solutions over the experimental period, and(3) promoted in the early stage but decelerated in later stages by excess adsorption of Fe by cells when the Fe(Ⅲ) concentration was higher than 500 μg/L in the solutions. The maximum cell density, total and cell chlorophyll-a were all observed at 500 μg Fe(Ⅲ)/L concentration. The organic elemental composition of M. aeruginosa was also affected by the concentration of Fe(Ⅲ) in the solutions, and the molecular formula of M. aeruginosa should be expressed as C7–7.5H14O0.8–1.3N3.5–5according to the functions for different Fe(Ⅲ)concentrations. Cell carbon and oxygen content appeared to increase slightly, while cell nitrogen content appeared to decrease as Fe(Ⅲ) concentrations increased from 100 to 500 μg/L in the solutions. This was attributed to the competition of photosynthesis and nitrogen adsorption under varying cell Fe content. 展开更多
关键词 High nitrate Low chlorophyll Fe Microcystis aeruginosa Cell chlorophyll a organic element composition
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A preliminary quantitative reconstruction of precipitation in southern Mu Us sandy land at margin of Asian monsoon-dominated region during late Quaternary 被引量:6
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作者 CHEN Yingyong LU Huayu +4 位作者 YI Shuangwen ZHANG Enlou XU Zhiwei YU Kaifeng Joseph A. MASON 《Journal of Geographical Sciences》 SCIE CSCD 2015年第3期301-310,共10页
We present the first quantitative estimation of monsoon precipitation during the late glaciaI-Holocene in the sandy land of northern China, based on organic carbon isotopic composition data from a loess-sand sequence ... We present the first quantitative estimation of monsoon precipitation during the late glaciaI-Holocene in the sandy land of northern China, based on organic carbon isotopic composition data from a loess-sand sequence at margin of the Mu Us sandy land. We use the relationship between monsoon precipitation and the carbon isotopic composition of modern soils as an analogue, with a minor modification, to reconstruct precipitation back to c. 47 ka ago. The preliminary results indicate that annual monsoon precipitation was high after 8 ka, with an average of 435 mm; and it decreased during 18 and 8 ka with a mean value of 194 mm. The precipitation value of 47-18 ka varied between the two. We compare the recon- structed precipitation with other records and paleoclimatic modeling results, showing that our record agrees with reconstructions of the monsoon precipitation from other sources, even capturing short climatic events such as the Younger Dryas. We suggest that solar irradiance, high-latitude temperature/ice volume and local evaporation have together modified moistures in the sandy land. 展开更多
关键词 quantitative reconstruction organic carbon isotopic composition PRECIPITATION Mu Us sandy land Asian monsoon
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Marx's Labor Theory of Value and Its Implications for Structural Problems in China's Economy 被引量:4
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作者 BANGXI LI 《Economic and Political Studies》 2014年第2期139-150,共12页
This paper computes the values of commodities(including fixed capital) as well as production prices in China's economy. In light of Marx's transformation problem, the ratios of production prices to the values ... This paper computes the values of commodities(including fixed capital) as well as production prices in China's economy. In light of Marx's transformation problem, the ratios of production prices to the values of 24 major commodities are computed. It is shown that the ratio of price to value in agriculture is the lowest, which indicates that agriculture is facing an unequal exchange of labor with other sectors. 展开更多
关键词 Marx's transformation problem organic composition of capital fixed capital-labor ratio unequal exchange of labor agriculture in China
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