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Co/CoO heterojunction rich in oxygen vacancies introduced by O2 plasma embedded in mesoporous walls of carbon nanoboxes covered with carbon nanotubes for rechargeable zinc-air battery 被引量:1
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作者 Leijun Ye Weiheng Chen +1 位作者 Zhong-Jie Jiang Zhongqing Jiang 《Carbon Energy》 SCIE EI CAS CSCD 2024年第7期14-25,共12页
Herein,Co/CoO heterojunction nanoparticles(NPs)rich in oxygen vacancies embedded in mesoporous walls of nitrogen-doped hollow carbon nanoboxes coupled with nitrogen-doped carbon nanotubes(P-Co/CoOV@NHCNB@NCNT)are well... Herein,Co/CoO heterojunction nanoparticles(NPs)rich in oxygen vacancies embedded in mesoporous walls of nitrogen-doped hollow carbon nanoboxes coupled with nitrogen-doped carbon nanotubes(P-Co/CoOV@NHCNB@NCNT)are well designed through zeolite-imidazole framework(ZIF-67)carbonization,chemical vapor deposition,and O_(2) plasma treatment.As a result,the threedimensional NHCNBs coupled with NCNTs and unique heterojunction with rich oxygen vacancies reduce the charge transport resistance and accelerate the catalytic reaction rate of the P-Co/CoOV@NHCNB@NCNT,and they display exceedingly good electrocatalytic performance for oxygen reduction reaction(ORR,halfwave potential[EORR,1/2=0.855 V vs.reversible hydrogen electrode])and oxygen evolution reaction(OER,overpotential(η_(OER,10)=377mV@10mA cm^(−2)),which exceeds that of the commercial Pt/C+RuO_(2) and most of the formerly reported electrocatalysts.Impressively,both the aqueous and flexible foldable all-solid-state rechargeable zinc-air batteries(ZABs)assembled with the P-Co/CoOV@NHCNB@NCNT catalyst reveal a large maximum power density and outstanding long-term cycling stability.First-principles density functional theory calculations show that the formation of heterojunctions and oxygen vacancies enhances conductivity,reduces reaction energy barriers,and accelerates reaction kinetics rates.This work opens up a new avenue for the facile construction of highly active,structurally stable,and cost-effective bifunctional catalysts for ZABs. 展开更多
关键词 HETEROJUNCTION oxygen evolution/reduction reaction oxygen vacancies rechargeable zinc–air battery three‐dimensional nitrogen‐doped hollow carbon nanoboxes
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Carbon enhanced nucleophilicity of Na_(3)V_(2)(PO_(4))_(3):A general approach for dendrite-free zinc metal anodes
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作者 Sijun Wang Lingzi Hu +8 位作者 Xiaohui Li Dan Qiu Shunhang Qiu Qiancheng Zhou Wenwen Deng Xiaoying Lu Ze Yang Ming Qiu Ying Yu 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第4期203-212,共10页
Zincophilic property and high electrical conductivity are both very important parameters to design novel Zn anode for aqueous Zn-ion batteries(AZIBs).However,single material is difficult to exhibit zincophilic propert... Zincophilic property and high electrical conductivity are both very important parameters to design novel Zn anode for aqueous Zn-ion batteries(AZIBs).However,single material is difficult to exhibit zincophilic property and high electrical conductivity at the same time.Herein,originating from theoretical calculation,a zincophilic particle regulation strategy is proposed to address these limitations and carbon coated Na_(3)V_(2)(PO_(4))_(3)is taken as an example to be a protective layer on zinc metal(NVPC@Zn).Na_(3)V_(2)(PO_(4))_(3)(NVP)is a common cathode material for Zn-ion batteries,which is zincophilic.Carbon materials not only offer an electron pathway to help Zn deposition onto NVPC surface,but also enhance the zinc nucleophilicity of Na_(3)V_(2)(PO_(4))_(3).Hence,this hybrid coating layer can tune zinc deposition and resist side reactions such as hydrogen generation and Zn metal corrosion.Experimentally,a symmetrical battery with NVPC@Zn electrode displays highly reversible plating/stripping behavior with a long cycle lifespan over 1800 h at2 mA cm^(-2),much better than carbon and Na_(3)V_(2)(PO_(4))_(3)solely modified Zn electrodes.When the Na_(3)V_(2)(PO_(4))_(3)is replaced with zincophobic Al2O3or zincophilic V2O3,the stability of the modified zinc anodes is also prolonged.This strategy expands the option of zincophilic materials and provides a general and effective way to stabilize the Zn electrode. 展开更多
关键词 zinc-ion batteries zinc anode carbon enhanced nucleophilicity zincophilic particle regulation
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Status and Opportunities of Zinc Ion Hybrid Capacitors: Focus on Carbon Materials, Current Collectors, and Separators 被引量:6
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作者 Yanyan Wang Shirong Sun +2 位作者 Xiaoliang Wu Hanfeng Liang Wenli Zhang 《Nano-Micro Letters》 SCIE EI CAS CSCD 2023年第6期73-111,共39页
Zinc ion hybrid capacitors(ZIHCs), which integrate the features of the high power of supercapacitors and the high energy of zinc ion batteries, are promising competitors in future electrochemical energy storage applic... Zinc ion hybrid capacitors(ZIHCs), which integrate the features of the high power of supercapacitors and the high energy of zinc ion batteries, are promising competitors in future electrochemical energy storage applications. Carbon-based materials are deemed the competitive candidates for cathodes of ZIHC due to their cost-effectiveness, high electronic conductivity, chemical inertness, controllable surface states, and tunable pore architectures. In recent years, great research efforts have been devoted to further improving the energy density and cycling stability of ZIHCs. Reasonable modification and optimization of carbon-based materials offer a remedy for these challenges. In this review, the structural design, and electrochemical properties of carbon-based cathode materials with different dimensions, as well as the selection of compatible, robust current collectors and separators for ZIHCs are discussed. The challenges and prospects of ZIHCs are showcased to guide the innovative development of carbon-based cathode materials and the development of novel ZIHCs. 展开更多
关键词 zinc ion hybrid capacitors carbon materials carbon cathode Current collectors SEPARATORS
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Chitosan derived carbon membranes as protective layers on zinc anodes for aqueous zinc batteries 被引量:1
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作者 Haichao Li Zengwu Wei +2 位作者 Yu Xia Junshan Han Xing Li 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2023年第4期621-629,共9页
Aqueous zinc batteries with low cost and inherent safety are considered to be the most promising energy storage devices.However,they suffer from poor cycling stability and low coulombic efficiencies caused by the adve... Aqueous zinc batteries with low cost and inherent safety are considered to be the most promising energy storage devices.However,they suffer from poor cycling stability and low coulombic efficiencies caused by the adverse zinc dendrites on the anodes during the discharging/charging processes.Chitosan is a kind of natural amino polysaccharide,which is rich in nitrogen and carbon.When sintered at high temperatures,carbon membranes have been achieved with excellent conductivity and graphitization degree,which could enhance the ability to induce zinc ion uniform deposition to some extent.In this work,a type of carbon membrane using chitosan as raw materials has been fabricated by sintering,and then assembled as the protect layers in aqueous zinc batteries.The results show that the samples could retain smoother surfaces when adopting the sintering temperature of 800℃,and the assembled batteries are able to achieve about 700 h at a current density of 0.25m A·cm^(-2),which is far longer than those of the similar batteries without any carbon membranes. 展开更多
关键词 carbon membrane DENDRITES CHITOSAN sintering process zinc batteries
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Sulfidation roasting of lead and zinc carbonate with sulphur by temperature gradient method 被引量:6
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作者 郑永兴 刘维 +4 位作者 覃文庆 焦芬 韩俊伟 杨康 罗虹霖 《Journal of Central South University》 SCIE EI CAS CSCD 2015年第5期1635-1642,共8页
In order to enhance the lead and zinc recovery from the refractory Pb-Zn oxide ore, a new technology was developed based on sulfidation roasting with sulphur by temperature gradient method. The solid-liquid reaction s... In order to enhance the lead and zinc recovery from the refractory Pb-Zn oxide ore, a new technology was developed based on sulfidation roasting with sulphur by temperature gradient method. The solid-liquid reaction system was established and the sulfidation thermodynamics of lead and zinc carbonate was calculated with the software HSC 5.0. The effects of roasting temperature,molar ratio of sulphur to lead and zinc carbonate and reaction time in the first step roasting, and holding temperature and time in the second roasting on the sulfidation extent were studied at a laboratory-scale. The experimental results show that the sulfidation extents of lead and zinc are 96.50% and 97.29% under the optimal conditions, respectively, and the artificial galena, sphalerite and wurtzite were formed. By the novel sulfidizing process, it is expected that the sulphides can be recovered by conventional flotation technology. 展开更多
关键词 lead and zinc carbonate SULPHUR ROASTING temperature gradient PYROMETALLURGY
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THERMAL DECOMPOSITION OF ZINC CARBONATE HYDROXIDE HYDRATE POWDERS OF DIFFERENT PARTICLE SIZE AND SAMPLE MASS 被引量:2
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作者 Chen Jianxun, Zhao Ruirong and Jiang HanyingInstitute of Metallurgy Physical Chemistry and New Chemical Materials,Central South University of Technology, Changsha 410083, P. R. ChinaLi Yanhong, Bao GailingInstitute of Chemistry and Chemical Eng 《中国有色金属学会会刊:英文版》 CSCD 1998年第1期150-154,共5页
THERMALDECOMPOSITIONOFZINCCARBONATEHYDROXIDEHYDRATEPOWDERSOFDIFFERENTPARTICLESIZEANDSAMPLEMASS①ChenJianxun,Z... THERMALDECOMPOSITIONOFZINCCARBONATEHYDROXIDEHYDRATEPOWDERSOFDIFFERENTPARTICLESIZEANDSAMPLEMASS①ChenJianxun,ZhaoRuirongandJian... 展开更多
关键词 zinc carbonate HYDROXIDE HYDRATE THERMAL DECOMPOSITION ZnO powder
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Investigation on the deactivation cause of lead-zinc double oxide for the synthesis of diphenyl carbonate by transesterification 被引量:3
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作者 Zhihui Li Yanji Wang +1 位作者 Xiaoshu Ding Xinqiang Zhao 《Journal of Natural Gas Chemistry》 EI CAS CSCD 2009年第1期104-109,共6页
The deactivation cause of lead-zinc double oxide for synthesis of diphenyl carbonate (DPC) by transesterification of dimethyl carbonate (DMC) with phenol has been investigated. X-ray diffraction (XRD), X-ray pho... The deactivation cause of lead-zinc double oxide for synthesis of diphenyl carbonate (DPC) by transesterification of dimethyl carbonate (DMC) with phenol has been investigated. X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), infrared spectroscopy (IR), thermogravimetry analysis (TG), atomic absorption spectroscopy and elementary analysis are employed for the catalyst characterization. The results show that, the formation of Pb4O(OC6H5)6 through the reaction of phenol and lead species in the catalyst leads to the crystal phase change of active component and serious leaching of lead, which is the cause of the catalyst deactivation. In addition, the composition of the leached lead is ascertained to be a mixture of Pb4O(OC6H5)6 and PbO with the weight percentage of 62.7% and 37.3%, respectively. 展开更多
关键词 lead-zinc double oxide DEACTIVATION dimethyl carbonate TRANSESTERIFICATION diphenyl carbonate organic lead
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An experimental study on metal precipitation driven by fluid mixing: implications for genesis of carbonate-hosted lead–zinc ore deposits 被引量:3
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作者 Yan Zhang Runsheng Han +2 位作者 Xing Ding Junjie He Yurong Wang 《Acta Geochimica》 EI CAS CSCD 2019年第2期202-215,共14页
A type of carbonate-hosted lead–zinc(Pb–Zn)ore deposits, known as Mississippi Valley Type(MVT)deposits, constitutes an important category of lead–zinc ore deposits. Previous studies proposed a fluid-mixing model to... A type of carbonate-hosted lead–zinc(Pb–Zn)ore deposits, known as Mississippi Valley Type(MVT)deposits, constitutes an important category of lead–zinc ore deposits. Previous studies proposed a fluid-mixing model to account for metal precipitation mechanism of the MVT ore deposits, in which fluids with metal-chloride complexes happen to mix with fluids with reduced sulfur, producing metal sulfide deposition. In this hypothesis, however, the detailed chemical kinetic process of mixing reactions, and especially the controlling factors on the metal precipitation are not yet clearly stated. In this paper, a series of mixing experiments under ambient temperature and pressure conditions were conducted to simulate the fluid mixing process, by titrating the metal-chloride solutions, doping withor without dolomite, and using NaHS solution. Experimental results, combined with the thermodynamic calculations, suggest that H_2S, rather than HS^-or S^(2-),dominated the reactions of Pb and/or Zn precipitation during the fluid mixing process, in which metal precipitation was influenced by the stability of metal complexes and the pH. Given the constant concentrations of metal and total S in fluids, the pH was a primary factor controlling the Pb and/or Zn metal precipitation. This is because neutralizing or neutralized processes for the ore-forming fluids can cause instabilities of Pb and/or Zn chloride complexes and re-distribution of sulfur species, and thus can facilitate the hydrolysis of Pb and Zn ions and precipitation of sulfides. Therefore, a weakly acidic to neutral fluid environment is most favorable for the precipitation of Pb and Zn sulfides associated with the carbonate-hosted Pb–Zn deposits. 展开更多
关键词 METAL PRECIPITATION Fluid mixing Sulfur species MVT lead-zinc ORE DEPOSITS carbonate-hosted lead-zinc DEPOSITS
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Phase Transformation of Amorphous Calcium Carbonate to Single-Crystalline Aragonite with Macroscopic Layered Structure in the Presence of Egg White Protein and Zinc Ion
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作者 曾辉 XIE Jingjing +4 位作者 PING Hang WANG Menghu XIE Hao WANG Weimin 傅正义 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2015年第1期65-70,共6页
Highly oriented calcium carbonate lamellas are exquisite structure produced by biomineralization. Strategies mimicking nature have been developed to synthesize inorganic materials with excellent structures and optimal... Highly oriented calcium carbonate lamellas are exquisite structure produced by biomineralization. Strategies mimicking nature have been developed to synthesize inorganic materials with excellent structures and optimal properties. In our strategy, egg white protein and zinc ion were employed in the solution to induce the crystallization of calcium carbonate, resulting in the macroscopic aragonite laminate with an average length of 1.5 mm, which was comprised of single-crystalline tablets. During the crystallization at initial stage, it was found that the particles displayed the characteristics of amorphous calcium carbonate, which was then transformed into the sophisticated structured aragonite through a multistage assembly process. The rebuilt nacre structure in vitro was achieved owing to the synergistic effects of egg white protein and zinc ion. 展开更多
关键词 calcium carbonate ACC ARAGONITE egg white protein zinc ion
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Effects of Copper-Zinc Alloy Doped with Rare Earth Elements on Crystal of Calcium Carbonate 被引量:1
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作者 丁燕 聂磊 +2 位作者 梁金生 汤庆国 陈蔓蔓 《Journal of Rare Earths》 SCIE EI CAS CSCD 2007年第S1期448-451,共4页
A copper-zinc alloy doped with rare earth elements was prepared and the mechanism was demonstrated in a simulating boiler and circulating cooling water with rigidity 1 mmol·L-1. The polar curve and scale inhibiti... A copper-zinc alloy doped with rare earth elements was prepared and the mechanism was demonstrated in a simulating boiler and circulating cooling water with rigidity 1 mmol·L-1. The polar curve and scale inhibiting ability of the alloy was tested by a corrosion measurement system and a scale inhibition evaluation system, respectively. Scale samples were characterized with SEM and XRD. It is found that the transfer of cations could be promoted by doping with proper rare earth elements, and the corrosion potentials descend by 25~126 mV. The results indicated that the copper-zinc alloy doped with rare earth elements has higher scale inhibiting ability of CaCO3. The growth of calcite was affected by zinc ions dissolved because of primary battery reaction, and the transition of calcium carbonate from aragonite to calcite was hampered resulting in the proportion of aragonite to calcite is changed from 1.7∶1 to 2.7∶1. 展开更多
关键词 rare earth elements copper-zinc alloy calcium carbonate CALCITE ARAGONITE scale inhibit CRYSTAL
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Chemical fixation of carbon dioxide to cyclic carbonates catalyzed by zinc(Ⅱ) complex bearing 1,2-disubstituted benzimidazole ligand
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作者 Jorge L. S. Milani Igor S. Oliveira +4 位作者 Pamella A. Dos Santos Ana K. S. M. Valdo Felipe T. Martins Danielle Cangussu Rafael P.Das Chagas 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 北大核心 2018年第2期245-249,共5页
A new zinc(II)complex of formula[ZnCl2(L1)2](1)[L1=2‐(2‐thienyl)‐1‐(2‐thienylmethyl)‐1Hbenzimidazole]was synthesized and fully characterized by nuclear magnetic resonance and infrared spectroscopy,elemental anal... A new zinc(II)complex of formula[ZnCl2(L1)2](1)[L1=2‐(2‐thienyl)‐1‐(2‐thienylmethyl)‐1Hbenzimidazole]was synthesized and fully characterized by nuclear magnetic resonance and infrared spectroscopy,elemental analysis,electrospray ionization high‐resolution mass spectrometry,and thermogravimetric analysis.The molecular structure was confirmed by single‐crystal X‐ray diffraction.Complex1consists of mononuclear tetrahedral zinc(II)units with a locked geometry resulting from weak intramolecular S···?and?–?interligand interactions.The benzimidazole ligand and its zinc(II)complex were readily obtained through a simple synthetic route.The catalytic activity of1was investigated in the coupling of carbon dioxide with epoxides to produce cyclic carbonates,and a series of parameters were evaluated.The complex efficiently catalyzed the transformation of various epoxides under solvent‐free conditions,with good conversions,turnover numbers,and turnover frequencies. 展开更多
关键词 carbon dioxide Cyclic carbonate zinc complex Benzimidazole ligand CYCLOADDITION Homogeneous catalysis
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High Performance Hydroxide Zinc Carbonate Composite for Supercapacitors
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作者 Yu Zhao Yubin Yang Ruiming Ren 《Journal of Materials Science and Chemical Engineering》 2019年第11期54-60,共7页
Energy density and production cost for high-performance electrode materials are the main challenge for the capacitive storage technology. In this paper, novel Hydroxide Zinc Carbonate (Zn4CO3(OH)6&#183;H2O, HZC) c... Energy density and production cost for high-performance electrode materials are the main challenge for the capacitive storage technology. In this paper, novel Hydroxide Zinc Carbonate (Zn4CO3(OH)6&#183;H2O, HZC) catalyst layers, which are composed of irregular stagger arrangement nanosheets, have been synthesized successfully on foam Ni from inorganic precursors by a feasible in situ hydrothermal method. Measured by electrochemical tests as electrode materials for supercapacitors, the HZC@Ni foam show high specific capacitance (1329.2 F&#183;g&#8722;1 at 1 A&#183;g&#8722;1 and 882.8 F&#183;g&#8722;1 at 10 A&#183;g&#8722;1, respectively). These results show that the HZC@Ni foam could be a potential electrode material for supercapacitors. These encouraging results make these low-cost and eco-friendly materials promising for energy storage application. 展开更多
关键词 HYDROXIDE zinc carbonate In SITU HYDROTHERMAL Method SUPERCAPACITOR Specific Capacitance
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Enhanced visible-light photocatalytic activity of Z-scheme graphitic carbon nitride/oxygen vacancy-rich zinc oxide hybrid photocatalysts 被引量:15
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作者 刘亚男 王瑞霞 +5 位作者 杨正坤 杜虹 姜一帆 申丛丛 梁况 徐安武 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 北大核心 2015年第12期2135-2144,共10页
With the objectives of enhancing the stability,optical properties and visible-light photocatalytic activity of photocatalysts,we modified oxygen vacancy-rich zinc oxide(Vo-ZnO) with graphitic carbon nitride(g-C3N4... With the objectives of enhancing the stability,optical properties and visible-light photocatalytic activity of photocatalysts,we modified oxygen vacancy-rich zinc oxide(Vo-ZnO) with graphitic carbon nitride(g-C3N4). The resulting g-C3N4/Vo-ZnO hybrid photocatalysts showed higher visible-light photocatalytic activity than pure Vo-ZnO and g-C3N4. The hybrid photocatalyst with a g-C3N4 content of 1 wt% exhibited the highest photocatalytic degradation activity under visible-light irradiation(λ≥ 400 nm). In addition,the g-C3N4/Vo-ZnO photocatalyst was not deactivated after five cycles of methyl orange degradation,indicating that it is stable under light irradiation. Finally,a Z-scheme mechanism for the enhanced photocatalytic activity and stability of the g-C3N4/Vo-ZnO hybrid photocatalyst was proposed. The fast charge separation and transport within the g-C3N4/Vo-ZnO hybrid photocatalyst were attributed as the origins of its enhanced photocatalytic performance. 展开更多
关键词 Oxygen deficient zinc oxide Graphitic carbon nitride Hybrid photocatalysts PHOTODEGRADATION Z-scheme
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The Effects of Three Mineral Nitrogen Sources and Zinc on Maize and Wheat Straw Decomposition and Soil Organic Carbon 被引量:8
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作者 Ogunniyi Jumoke Esther GUO Chun-hui +2 位作者 TIAN Xiao-hong LI Hong-yun ZHOU Yang-xue 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2014年第12期2768-2777,共10页
The incorporation of straw in cultivated ifelds can potentially improve soil quality and crop yield. However, the presence of recalcitrant carbon compounds in straw slow its decomposition rate. The objective of this s... The incorporation of straw in cultivated ifelds can potentially improve soil quality and crop yield. However, the presence of recalcitrant carbon compounds in straw slow its decomposition rate. The objective of this study was to determine the effects of different nitrogen sources, with and without the application of zinc, on straw decomposition and soil quality. Soils were treated with three different nitrogen sources, with and without zinc: urea (CO(NH2)2), ammonium sulfate ((NH4)2SO4), and ammonium chloride (NH4Cl). The combined treatments were as follows:maize (M) and wheat (W) straw incorporated into urea-, ammonium sulfate-, or ammonium chloride-treated soil (U, S, and C, respectively) with and without zinc (Z) (MU, MUZ, WU, WUZ;MS, MSZ, WS, WSZ;MC, MCZ, WC, WCZ, respectively);straw with zinc only (MZ, WZ);straw with untreated soil (MS, WS);and soil-only or control conditions (NT). The experiment consisted of 17 treatments with four replications. Each pot contained 150 g soil and 1.125 g straw, had a moisture content of 80%of the ifeld capacity, and was incubated for 53 days at 25°C. The rates of CO2-C emission, cumulative CO2-C evolution, total CO2 production in the soils of different treatments were measured to infer decomposition rates. The total organic carbon (TOC), labile organic carbon (LOC), and soil microbial biomass in the soils of different treatments were measured to infer soil quality. All results were signiifcantly different (P〈0.05) with the exception of the labile organic carbon (LOC). The maize and wheat straw showed different patterns in CO2 evolution rates. For both straw types, Zn had a synergic effect with U, but an antagonistic effect with the other N sources as determined by the total CO2 produced. The MUZ treatment showed the highest decomposition rate and cumulative CO2 concentration (1 120.29 mg/pot), whereas the WACZ treatment had the lowest cumulative CO2 concentration (1 040.57 mg/pot). The addition of NH4Cl resulted in the highest total organic carbon (TOC) concentration (11.59 mg kg-1). The incorporation of wheat straw resulted in higher microbial biomass accumulation in soils relative to that of the maize straw application. The results demonstrate that mineral N sources can affect the ability of microorganisms to decompose straw, as well as the soil carbon concentrations. 展开更多
关键词 nitrogen sources zinc carbon fractions straw mineralization wheat straw maize straw LOC
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Nitrogen-doped carbon nanotube encapsulating cobalt nanoparticles towards efficient oxygen reduction for zinc–air battery 被引量:4
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作者 Haihua Wu Xiaole Jiang +5 位作者 Yifan Ye Chengcheng Yan Songhai Xie Shu Miao Guoxiong Wang Xinhe Bao 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2017年第6期1181-1186,共6页
Nitrogen-doped carbon materials encapsulating 3 d transition metals are promising alternatives to replace noble metal Pt catalysts for efficiently catalyzing the oxygen reduction reaction(ORR). Herein, we use cobalt s... Nitrogen-doped carbon materials encapsulating 3 d transition metals are promising alternatives to replace noble metal Pt catalysts for efficiently catalyzing the oxygen reduction reaction(ORR). Herein, we use cobalt substituted perfluorosulfonic acid/polytetrafluoroethylene copolymer and dicyandiamide as the pyrolysis precursor to synthesize nitrogen-doped carbon nanotube(N–CNT) encapsulating cobalt nanoparticles hybrid material. The carbon layers and specific surface area of N–CNT have a critical role to the ORR performance due to the exposed active sites, determined by the mass ratio of the two precursors. The optimum hybrid material exhibits high ORR activity and stability, as well as excellent performance and durability in zinc–air battery. 展开更多
关键词 Nitrogen-doped carbon nanotube Perfluorosulfonic Acid/polytetrafluoroethylene copolymer Cobalt substitution Oxygen reduction reaction zinc–air battery
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Three‑Dimensional Ordered Mesoporous Carbon Spheres Modified with Ultrafine Zinc Oxide Nanoparticles for Enhanced Microwave Absorption Properties 被引量:11
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作者 Yan Song Fuxing Yin +3 位作者 Chengwei Zhang Weibing Guo Liying Han Ye Yuan 《Nano-Micro Letters》 SCIE EI CAS CSCD 2021年第5期61-76,共16页
Currently,electromagnetic radiation and interference have a significant effect on the operation of electronic devices and human health systems.Thus,developing excellent microwave absorbers have a huge significance in ... Currently,electromagnetic radiation and interference have a significant effect on the operation of electronic devices and human health systems.Thus,developing excellent microwave absorbers have a huge significance in the material research field.Herein,a kind of ultrafine zinc oxide(ZnO)nanoparticles(NPs)supported on three-dimensional(3D)ordered mesoporous carbon spheres(ZnO/OMCS)is prepared from silica inverse opal by using phenolic resol precursor as carbon source.The prepared lightweight ZnO/OMCS nanocomposites exhibit 3D ordered carbon sphere array and highly dispersed ultrafine ZnO NPs on the mesoporous cell walls of carbon spheres.ZnO/OMCS-30 shows microwave absorbing ability with a strong absorption(−39.3 dB at 10.4 GHz with a small thickness of 2 mm)and a broad effective absorption bandwidth(9.1 GHz).The outstanding microwave absorbing ability benefits to the well-dispersed ultrafine ZnO NPs and the 3D ordered mesoporous carbon spheres structure.This work opened up a unique way for developing lightweight and high-efficient carbon-based microwave absorbing materials. 展开更多
关键词 Three-dimensional ordered structure Mesoporous carbon spheres zinc oxide nanoparticles Microwave absorption
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Zinc single atoms on N-doped carbon: An efficient and stable catalyst for CO2 fixation and conversion 被引量:2
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作者 Xinjiang Cui Xingchao Dai +5 位作者 Annette-Enrica Surkus Kathrin Junge Carsten Kreyenschulte Giovanni Agostini Nils Rockstroh Matthias Beller 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 北大核心 2019年第11期1679-1685,共7页
The cycloaddition of epoxides and carbon dioxide represents a straightforward and atom-efficient method for synthesis of cyclic carbonates and utilization of CO2. So far, homogeneous metal complexes have been mainly a... The cycloaddition of epoxides and carbon dioxide represents a straightforward and atom-efficient method for synthesis of cyclic carbonates and utilization of CO2. So far, homogeneous metal complexes have been mainly applied for such transformations. Here, we describe the synthesis of novel heterogeneous Zn-based catalysts, which were conveniently prepared by pyrolysis of an active- carbon-supported phenanthroline-ligated Zn(OAc)2 complex. Detail structural characterizations proved the existence of single zinc sites in the active material. Compared to a Zn-based nanoparticle (Zn-NP) catalyst, the resulting single metal atom catalyst (SAC) displayed improved activity and stability for the cycloaddition of epoxides. By applying the optimal catalyst, a variety of carbonates were successfully obtained in high yields with good functional group tolerance. 展开更多
关键词 Heterogeneous catalysis Single atom catalyst zinc carbon dioxide CYCLOADDITION carbonate
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Photocatalytic degradation of sulfamethazine by graphitic carbon nitride-modified zinc molybdate:Effects of synthesis method on performance, degradation kinetics,and mechanism 被引量:4
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作者 Jing Zhang Xuhui Mao +1 位作者 Wei Xiao Yanfeng Zhuang 《Chinese Journal of Catalysis》 CSCD 北大核心 2017年第12期2009-2020,共12页
In the present study,zinc molybdate(β‐ZnMoO4)and graphitic carbon nitride(g‐C3N4)‐modifiedβ‐ZnMoO4(β‐ZnMoO4/g‐C3N4)were prepared to decontaminate aqueous solutions from the antibiotic sulfamethazine(SMZ).Our ... In the present study,zinc molybdate(β‐ZnMoO4)and graphitic carbon nitride(g‐C3N4)‐modifiedβ‐ZnMoO4(β‐ZnMoO4/g‐C3N4)were prepared to decontaminate aqueous solutions from the antibiotic sulfamethazine(SMZ).Our results revealed that the hydrothermal synthesis method greatly influenced the photocatalytic activity of the resultant catalysts.The pristineβ‐ZnMoO4samples obtained under more intensive synthesis conditions(24h at280°C)showed higher photocatalytic activity than that prepared for12h at180°C(denotedβ‐ZnMoO4‐180).In the case of in situ hydrothermal synthesis ofβ‐ZnMoO4/g‐C3N4,a surface‐modified sample was only obtained under the reaction conditions of180°C for12h.Compared with the sheet‐likeβ‐ZnMoO4‐180sample,theβ‐ZnMoO4‐180/g‐C3N4composite showed enhanced photocatalytic activity for the degradation of SMZ.By contrast,the hydrothermal reaction at280°C caused the gradual decomposition of g‐C3N4.It is believed that the structural incorporation of g‐C3N4intoβ‐ZnMoO4at280°C might disrupt the crystal growth,thereby deteriorating the performance of the composite catalysts formed at this temperature.For the composite catalysts prepared by the ultrasonic method,a remarkable increase in the degradation rate of SMZ was only observed at a high g‐C3N4content of8mol%.The photocatalytic degradation of SMZ byβ‐ZnMoO4‐180/g‐C3N4composite catalysts followed pseudo‐first‐order kinetics.Further study of the photocatalytic mechanism revealed that holes and superoxide radicals were the dominant oxidative species in the photodegradation process.The enhanced photocatalytic performance of the composites was attributed to the higher separation efficiency of the photogenerated electron‐hole pairs at heterogeneous junctions.The degradation intermediates of SMZ were detected by liquid chromatography‐mass spectrometry,from which plausible reaction pathways for the photodegradation of SMZ were proposed.Our results indicated that the synthesis method for g‐C3N4composites should be carefully selected to achieve superior photocatalytic performance. 展开更多
关键词 zinc molybdate Graphitic carbon nitride PHOTOCATALYSIS SULFAMETHAZINE Water treatment
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Effect of zinc protoporphyrin on carbon monoxide/heme oxygenase-1 system in rats subjected to recurrent febrile convulsion 被引量:1
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作者 Xianhe Wang Jingyue Gu Xianghong Wu Qingyun Meng Mei Mei 《Neural Regeneration Research》 SCIE CAS CSCD 2007年第8期466-470,共5页
BACKGROUND: Studies on febrile convulsion (FC)-caused brain injury are disputed in many aspects. How FC cause nervous system injury in the developmental period and what are the characteristics of these pathological... BACKGROUND: Studies on febrile convulsion (FC)-caused brain injury are disputed in many aspects. How FC cause nervous system injury in the developmental period and what are the characteristics of these pathological injury are unknown. The current studies have demonstrated that berne oxygenase-1 (HO-1) exerts effects on brain injury mainly by catalyzing hemoglobin to produce degradation products, and HO-1 not only has neuroprotective effects, but also has neurotoxic effects during the FC-caused brain injury. Study on the effect of zinc protoporphyrin (ZnPP) on brain injury is still in the stage of animal experiment. OBJECTIVE: To observe the effects of ZnPP on carbon monoxide (CO)/HO-1 system of rats subjected to FC, and to analyze the action pathway of ZnPP in brain protective effect. DESIGN: A randomized controlled animal experiment. SETTING: Department of Pediatrics, First Hospital Affiliated to Jiamusi University. MATERIALS: Sixty-five Wistar rats, of either gender, were involved in this study. They were randomized into normal control group( n =14, 37℃ water bath) and febrile treatment group (n =51, 44.5℃ hot water bath). Febrile treatment group was sub-divided into febrile non-convulsion group (FNC group, n =16) and FC group (n =35). FC group was further sub-divided into simple convulsion group (n =20) and ZnPP treatment group (n =15). HO-1 mRNA in situ hybridization kit was provided by Boster Bioengineering Co.,Ltd. ZnPP(dark brown powder) was the product of Jingmei Bioengineering Company. METHODS: This study was carried out in the postgraduate laboratory of Jiamusi University between January 2004 and January 2007. Rats in the febrile treatment group were placed in the 44.5℃ hot water bath box. If rats did not convulse in the water within 5 minutes, they were taken out, namely FNC group (n = 16), and those, which were convulsed within 5 minutes, were taken out immediately when they presented such a phenomenon, namely FC group (n =35). Convulsion induction was conducted once every other day, totally 10 times. Rats were euthanized for analysis at 24 hours after the last induction. Rats in the control group were placed in the 37℃ water. Rats in the ZnPP treatment group were intraperitoneally injected with ZnPP at 45 μ mol/kg before FC attack. Rats in the simple convulsion group were only induced to be convulsed but not administrated. MAIN OUTCOME MEASURES: CO level in the brain tissue homogenate and plasma of rats in each group was detected with a spectrophotometer. HO-1 mRNA expression in the hippocampal CAI region, CA3 region and dentate gyrus of rats was observed by in situ hybridization technique. RESULTS: Sixty-five Wistar rats were involved in the study. Two rats died respectively due to drowning and convulsion in the FC group. One rat died due to convulsion drowning in the ZnPP treatment group. ①Plasma CO concentration of control group and ZnPP treatment group was significantly lower than that of the FC group (P 〈 0.01), and was significantly higher in the ZnPP treatment group than in the FNC group (P 〈 0.05). ②CO level in the brain tissue homogenate was significantly lower in the control group and ZnPP treatment group than in the FC group (P 〈 0.01), and was very significantly higher in the ZnPP treatment group than in the control group (P 〈 0.01). ③HO-1 mRNA expressions in the neuron of hippocampal CAl region, CA3 region and dentate gyrus of the control group were the lowerest, and those in the FC group were the highest. HO-1 mRNA expression in the neuron of dentate gyrus in the FC group was significantly higher than that in the ZnPP treatment group (P 〈 0.01), and those in the FNC group and control group was significantly lower than that in the ZnPP treatment group (P 〈 0.01). CONCLUSION: FC can cause brain injury. Over-expression of HO-I mRNA and the increase of CO are involved in the patho-physiological process of FC. ZnPP can inhibit HO-lmRNA activity and decrease CO level, which is one of pathways for protecting brain. 展开更多
关键词 zinc protoporphyrin febrile convulsion HEMEOXYGENASE carbon monoxide BRAIN
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Insertion of Selenium into Zinc Carbon Bond and Application in Synthesis of Arylselenoester 被引量:1
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作者 XinHuaXU WenQiLiU 《Chinese Chemical Letters》 SCIE CAS CSCD 2002年第4期283-284,共2页
Selenium was inserted into the zinc carbon bond of aryl zinc halides to form corresponding zinc selenoates. They reacted in THF-HMPA with acylhalides to afford the selenoesters in high yields.
关键词 SELENIUM insertion reaction zinc carbon bond acylhalides selenoester.
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