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Dietary supplementation of zinc oxide modulates intestinal functionality during the post-weaning period in clinically healthy piglets
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作者 Dirkjan Schokker Soumya K.Kar +3 位作者 Els Willems Alex Bossers Ruud A.Dekker Alfons J.M.Jansman 《Journal of Animal Science and Biotechnology》 SCIE CAS CSCD 2024年第1期313-328,共16页
Background To improve our understanding of host and intestinal microbiome interaction,this research investigated the effects of a high-level zinc oxide in the diet as model intervention on the intestinal microbiome an... Background To improve our understanding of host and intestinal microbiome interaction,this research investigated the effects of a high-level zinc oxide in the diet as model intervention on the intestinal microbiome and small intestinal functionality in clinically healthy post-weaning piglets.In study 1,piglets received either a high concentration of zinc(Zn)as zinc oxide(Zn O,Zn,2,690 mg/kg)or a low Zn concentration(100 mg/kg)in the diet during the post weaning period(d 14–23).The effects on the piglet's small intestinal microbiome and functionality of intestinal tissue were investigated.In study 2,the impact of timing of the dietary zinc intervention was investigated,i.e.,between d 0–14 and/or d 14–23 post weaning,and the consecutive effects on the piglet's intestinal functionality,here referring to microbiota composition and diversity and gene expression profiles.Results Differences in the small intestinal functionality were observed during the post weaning period between piglets receiving a diet with a low or high concentration Zn O content.A shift in the microbiota composition in the small intestine was observed that could be characterized as a non-pathological change,where mainly the commensals inter-changed.In the immediate post weaning period,i.e.,d 0–14,the highest number of differentially expressed genes(DEGs)in intestinal tissue were observed between animals receiving a diet with a low or high concentration Zn O content,i.e.,23 DEGs in jejunal tissue and 11 DEGs in ileal tissue.These genes are involved in biological processes related to immunity and inflammatory responses.For example,genes CD59 and REG3G were downregulated in the animals receiving a diet with a high concentration Zn O content compared to low Zn O content in both jejunum and ileum tissue.In the second study,a similar result was obtained regarding the expression of genes in intestinal tissue related to immune pathways when comparing piglets receiving a diet with a high concentration Zn O content compared to low Zn O content.Conclusions Supplementing a diet with a pharmaceutical level of Zn as Zn O for clinically healthy post weaning piglets influences various aspects intestinal functionality,in particular in the first two weeks post-weaning.The model intervention increased both the alpha diversity of the intestinal microbiome and the expression of a limited number of genes linked to the local immune system in intestinal tissue.The effects do not seem related to a direct antimicrobial effect of Zn O. 展开更多
关键词 Immune system Intestinal functionality MICROBIOTA PIGLETS zinc oxide
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Synergism of Zinc Oxide/Organoclay-Loaded Poly(lactic acid) Hybrid Nanocomposite Plasticized by Triacetin for Sustainable Active Food Packaging
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作者 Ponusa Songtipya Thummanoon Prodpran +1 位作者 Ladawan Songtipya Theerarat Sengsuk 《Journal of Renewable Materials》 EI CAS 2024年第5期951-967,共17页
The synergistic effect of organoclay(OC)and zinc oxide(ZnO)nanoparticles on the crucial properties of poly(lactic acid)(PLA)nanocompositefilms was systematically investigated herein.After their incorporation into PLA v... The synergistic effect of organoclay(OC)and zinc oxide(ZnO)nanoparticles on the crucial properties of poly(lactic acid)(PLA)nanocompositefilms was systematically investigated herein.After their incorporation into PLA via the solvent casting technique,the water vapor barrier property of the PLA/OC/ZnOfilm improved by a maximum of 86%compared to the neat PLAfilm without the deterioration of Young’s modulus or the tensile strength.Moreover,thefilm’s self-antibacterial activity against foodborne pathogens,including gram-negative(Escherichia coli,E.coli)and gram-positive(Staphylococcus aureus,S.aureus)bacteria,was enhanced by a max-imum of approximately 98–99%compared to the neat PLAfilm.Furthermore,SEM images revealed the homo-geneous dispersion of both nano-fillers in the PLA matrix.However,the thermal stability of thefilm decreased slightly after the addition of the OC and ZnO.Thefilm exhibited notable light barrier properties in the UV-Vis range.Moreover,the incorporation of a suitable biodegradable plasticizer significantly decreased the Tg and notably enhanced theflexibility of the nanocompositefilm by increasing the elongation at break approxi-mately 1.5-fold compared to that of the neat PLAfilm.This contributes to its feasibility as an active food packa-ging material. 展开更多
关键词 Poly(lactic acid)nanocomposite ORGANOCLAY zinc oxide barrier property antibacterial activity active food packaging
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Zinc-Based Metal-Organic Frameworks for High-Performance Supercapacitor Electrodes:Mechanism Underlying Pore Generation
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作者 Shigeyuki Umezawa Takashi Douura +6 位作者 Koji Yoshikawa Daisuke Tanaka Vlad Stolojan S.Ravi P.Silva Mika Yoneda Kazuma Gotoh Yasuhiko Hayashi 《Energy & Environmental Materials》 SCIE EI CAS CSCD 2023年第2期100-112,共13页
Heat treatment of metal-organic frameworks(MOFs)has provided a wide variety of functional carbons coordinated with metal compounds.In this study,two kinds of zinc-based MOF(ZMOF),C_(16)H_(10)O_(4)Zn(ZMOF1)and C_(8)H_(... Heat treatment of metal-organic frameworks(MOFs)has provided a wide variety of functional carbons coordinated with metal compounds.In this study,two kinds of zinc-based MOF(ZMOF),C_(16)H_(10)O_(4)Zn(ZMOF1)and C_(8)H_(4)O_(4)Zn(ZMOF2),were prepared.ZMOF1 and ZMOF2 were carbonized at 1000℃,forming CZMOF1 and CZMOF2,respectively.The specific surface area(S_(BET))of CZMOF2 was~2700 m^(2)g^(−1),much higher than that of CZMOF1(~1300 m^(2)g^(−1)).A supercapacitor electrode based on CZMOF2 achieved specific capacitances of 360,278,and 221 F g^(−1)at 50,250,and 1000 mA g^(−1)in an aqueous electrolyte(H2SO_(4)),respectively,the highest values reported to date for ZMOF-derived electrodes under identical conditions.The practical applicability of the CZMOF-based supercapacitor was verified in non-aqueous electrolytes.The initial capacitance retention was 78%after 100000 charge/discharge cycles at 10 A g^(−1).Crucially,the high capacitance of CZMOF2 arises from pore generation during carbonization.Below 1000℃,pore generation is dominated by the Zn/C ratio of ZMOFs,as carbon atoms reduce the zinc oxides formed during carbonization.Above 1000℃,a high O/C ratio becomes essential for pore generation because the oxygen functional groups are pyrolyzed.These findings will provide insightful information for other metal-based MOFderived multifunctional carbons. 展开更多
关键词 metal-organic frameworks pore generation porous carbons SUPERCAPACITOR zinc oxides
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Electronic and thermal properties of Ag-doped single crystal zinc oxide via laser-induced technique 被引量:1
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作者 邢欢 王惠琼 +5 位作者 宋廷鲁 李纯莉 戴扬 傅耿明 康俊勇 郑金成 《Chinese Physics B》 SCIE EI CAS CSCD 2023年第6期44-51,共8页
The doping of ZnO has attracted lots of attention because it is an important way to tune the properties of ZnO.Postdoping after growth is one of the efficient strategies.Here,we report a unique approach to successfull... The doping of ZnO has attracted lots of attention because it is an important way to tune the properties of ZnO.Postdoping after growth is one of the efficient strategies.Here,we report a unique approach to successfully dope the single crystalline ZnO with Ag by the laser-induced method,which can effectively further post-treat grown samples.Magnetron sputtering was used to coat the Ag film with a thickness of about 50 nm on the single crystalline ZnO.Neodymium-doped yttrium aluminum garnet(Nd:YAG)laser was chosen to irradiate the Ag-capped ZnO samples,followed by annealing at700℃for two hours to form ZnO:Ag.The three-dimensional(3D)information of the elemental distribution of Ag in ZnO was obtained through time-of-flight secondary ion mass spectrometry(TOF-SIMS).TOF-SIMS and core-level x-ray photoelectron spectroscopy(XPS)demonstrated that the Ag impurities could be effectively doped into single crystalline ZnO samples as deep as several hundred nanometers.Obvious broadening of core level XPS profiles of Ag from the surface to depths of hundred nms was observed,indicating the variance of chemical state changes in laser-induced Ag-doped ZnO.Interesting features of electronic mixing states were detected in the valence band XPS of ZnO:Ag,suggesting the strong coupling or interaction of Ag and ZnO in the sample rather than their simple mixture.The Ag-doped ZnO also showed a narrower bandgap and a decrease in thermal diffusion coefficient compared to the pure ZnO,which would be beneficial to thermoelectric performance. 展开更多
关键词 zinc oxide Ag-doping laser-induced technique XPS SIMS thermal diffusivity
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Effects of Zinc Oxide Particles with Different Sizes on Root Development in Oryza sativa
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作者 Monica RUFFINI CASTIGLIONE Stefania BOTTEGA +1 位作者 Carlo SORCE Carmelina SPANÒ 《Rice science》 SCIE CSCD 2023年第5期449-458,I0021,共11页
Given the consistent release of zinc oxide(ZnO)nanoparticles into the environment,it is urgent to study their impact on plants in depth.In this study,grains of rice were treated with two different concentrations of Zn... Given the consistent release of zinc oxide(ZnO)nanoparticles into the environment,it is urgent to study their impact on plants in depth.In this study,grains of rice were treated with two different concentrations of ZnO nanoparticles(NP-ZnO,10 and 100 mg/L),and their bulk counterpart(B-ZnO)were used to evaluate whether ZnO action could depend on particle size.To test this hypothesis,root growth and development assessment,oxidative stress parameters,indole-3-acetic acid(IAA)content and molecules/enzymes involved in IAA metabolism were analyzed.In situ localization of Zn in control and treated roots was also performed.Though Zn was visible inside root cells only following nanoparticle treatment,both materials(NP-ZnO and B-ZnO)were able to affect seedling growth and root morphology,with alteration in the concentration/pattern of localization of oxidative stress markers and with a different action depending on particle size.In addition,only ZnO supplied as bulk material induced a significant increase in both IAA concentration and lateral root density,supporting our hypothesis that bulk particles might enhance lateral root development through the rise of IAA concentration.Apparently,IAA concentration was influenced more by the activity of the catabolic peroxidases than by the protective action of phenols. 展开更多
关键词 zinc oxide indole-3-acetic acid lateral root rice bulk particle NANOPARTICLE
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Multi-Objective Adaptive Optimization Model Predictive Control:Decreasing Carbon Emissions from a Zinc Oxide Rotary Kiln
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作者 Ke Wei Keke Huang +1 位作者 Chunhua Yang Weihua Gui 《Engineering》 SCIE EI CAS CSCD 2023年第8期96-105,共10页
The zinc oxide rotary kiln,as an essential piece of equipment in the zinc smelting industrial process,is presenting new challenges in process control.China’s strategy of achieving a carbon peak and carbon neutrality ... The zinc oxide rotary kiln,as an essential piece of equipment in the zinc smelting industrial process,is presenting new challenges in process control.China’s strategy of achieving a carbon peak and carbon neutrality is putting new demands on the industry,including green production and the use of fewer resources;thus,traditional stability control is no longer suitable for multi-objective control tasks.Although researchers have revealed the principle of the rotary kiln and set up computational fluid dynamics(CFD)simulation models to study its dynamics,these models cannot be directly applied to process control due to their high computational complexity.To address these issues,this paper proposes a multi-objective adaptive optimization model predictive control(MAO-MPC)method based on sparse identification.More specifically,with a large amount of data collected from a CFD model,a sparse regression problem is first formulated and solved to obtain a reduction model.Then,a two-layered control framework including real-time optimization(RTO)and model predictive control(MPC)is designed.In the RTO layer,an optimization problem with the goal of achieving optimal operation performance and the lowest possible resource consumption is set up.By solving the optimization problem in real time,a suitable setting value is sent to the MPC layer to ensure that the zinc oxide rotary kiln always functions in an optimal state.Our experiments show the strength and reliability of the proposed method,which reduces the usage of coal while maintaining high profits. 展开更多
关键词 zinc oxide rotary kiln Model reduction Sparse identification Real-time optimization Model predictive control Process control
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Efficient degradation of dye pollutants in wastewater via photocatalysis using a magnetic zinc oxide/graphene/iron oxide-based catalyst
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作者 Piyawan Nuengmatcha Arnannit Kuyyogsuy +3 位作者 Paweena Porrawatkul Rungnapa Pimsen Saksit Chanthai Prawit Nuengmatcha 《Water Science and Engineering》 EI CAS CSCD 2023年第3期243-251,共9页
In this paper, we present a proof-of-concept study of the enhancement of photocatalytic activity via a combined strategy of fabricating a visible-light responsive ternary heterostructure and improving overall photosta... In this paper, we present a proof-of-concept study of the enhancement of photocatalytic activity via a combined strategy of fabricating a visible-light responsive ternary heterostructure and improving overall photostability by incorporating magnetic zinc oxide/graphene/iron oxide (ZGF). A solvothermal approach was used to synthesize the catalyst. X-ray diffraction (XRD), scanning electron microscopic, energy dispersive X-ray, transmission electron microscopic, vibrating sample magnetometric, and ultraviolet–visible diffuse reflectance spectroscopic techniques were used to characterize the synthesized samples. The obtained optimal Zn(NO_(3))_(2) concentration, temperature, and heating duration were 0.10 mol/L, 600℃, and 1 h, respectively. The XRD pattern revealed the presence of peaks corresponding to zinc oxide, graphene, and iron oxide, indicating that the ZGF catalyst was effectively synthesized. Furthermore, when the developed ZGF was used for methylene blue dye degradation, the optimum irradiation time, dye concentration, catalyst dosage, irradiation intensity, and solution pH were 90 min, 10 mg/L, 0.03 g/L, 100 W, and 8.0, respectively. Therefore, the synthesized ZGF system could be used as a catalyst to degrade dyes in wastewater samples. This hybrid nanocomposite consisting of zinc oxide, graphene, and iron oxide could also be used as an effective photocatalytic degrader for various dye pollutants. 展开更多
关键词 Magnetic zinc oxide/graphene/iron oxide PHOTOCATALYSIS Dye pollutants CATALYST Degradation
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Effect of Calcination Temperature on the Microstructure and Surface Properties of a Cu/ZnO Catalyst Derived from Zn_(3)Cu_(2)(OH)_(6)(CO_(3))_(2)
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作者 Qiu Shiming Wang Shengjie 《China Petroleum Processing & Petrochemical Technology》 SCIE CAS CSCD 2024年第2期46-56,共11页
The Cu/ZnO catalyst formed upon the calcination of aurichalcite has a uniform distribution of ZnO,which can delay the sintering of Cu species at high temperatures.In this study,aurichalcite possessing a nearly pure ph... The Cu/ZnO catalyst formed upon the calcination of aurichalcite has a uniform distribution of ZnO,which can delay the sintering of Cu species at high temperatures.In this study,aurichalcite possessing a nearly pure phase was prepared using the ammonium complex dissociation precipitation method,and the effect of calcination temperature on the structure and surface properties of the derived Cu/ZnO catalyst was studied.The results show that the calcination temperature determines the particle size and crystallization degree of the Cu/ZnO catalyst and the surface properties of the corresponding copper oxide and reduced copper.Low-temperature calcination is more conducive to reducing the particle size of the Cu/ZnO catalyst,increasing the specific surface area,and generating abundant defect characteristics on the surface,which is key to obtaining highly dispersed copper and copper-specific surface area catalysts by subsequent reduction.Additionally,the Cu/ZnO catalyst derived using a 300℃or 400℃calcination proved to have a higher specific activity per gram of copper than a commercial Cu/Zn/Al catalyst.The discovery in this study opens up a new method for the convenient preparation of a high-temperature resistant Cu/Zn methanol reforming catalyst. 展开更多
关键词 methanol reforming COPPER zinc oxide lattice defect
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Preparation and Performance Study of PVA-Based Flexible Sensors
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作者 Md Kamrul Hasan Xinbo Ding 《Open Journal of Polymer Chemistry》 2024年第1期19-40,共22页
Flexible sensors have great potential for monitoring human body motion signals. This paper presents a flexible sensor that uses zinc oxide (ZnO) to improve the mechanical properties and electrical conductivity of PVA ... Flexible sensors have great potential for monitoring human body motion signals. This paper presents a flexible sensor that uses zinc oxide (ZnO) to improve the mechanical properties and electrical conductivity of PVA hydrogel. The composite hydrogel has excellent conductive properties and high strain sensitivity, making it suitable for motion monitoring. The PVA/ZnO conductive hydrogel is tested on various body parts, showing effective feedback on movement changes and good electrical signal output effects for different motion degrees, confirming its feasibility in flexible sensors. The sensor exhibits good mechanical properties, electrical conductivity, and tensile strain sensing performance, making it a promising sensor material. It can accurately monitor wrist bending, finger deformation, bending, and large-scale joint movements due to its wide monitoring range and recoverable strain. The results show that the PVA/ZnO conductive hydrogel can provide effective feedback in flexible sensors, which is suitable for use in motion monitoring. 展开更多
关键词 Polyvinyl Alcohol zinc Oxide zinc Oxide Nanorods Conductive Hydrogel Flexible Sensor
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Wavelength Dependent Nonlinear Spectroscopic Study of Third Harmonic Generation Probed by Rotational Maker Fringes Method
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作者 Calford Odhiambo Otieno 《Open Journal of Microphysics》 2024年第2期13-23,共11页
Efficient third-order nonlinearities of the Zinc Oxide and Al-doped Zinc Oxide were studied by Third Harmonic Generation (Third Harmonic Generation) Maker fringes to establish the effect Aluminum of Aluminum doping (A... Efficient third-order nonlinearities of the Zinc Oxide and Al-doped Zinc Oxide were studied by Third Harmonic Generation (Third Harmonic Generation) Maker fringes to establish the effect Aluminum of Aluminum doping (Al-doping) on the cubic nonlinearities. Adding the Al-dopant to the Zinc Oxide crystal structure results in changes that affect the optical and nonlinear characteristics. Presented results indicate that the magnitude of X<sup>(3)</sup> was enhanced at single experimental wavelengths;however, across the broadband experimental spectrum, the effect of Al-doping remained relatively constant. The observed enhancement of third-order nonlinearity was purely from the bound electronic response. The observation is attributed to increased charge carriers and spontaneous polarization in the Zinc Oxide and Al-doped Zinc Oxide crystal structure. 展开更多
关键词 Nonlinear Optics Harmonic Generation Maker Fringes zinc Oxide
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Effect of RF power on the properties of transparent conducting zirconium-doped zinc oxide films prepared by RF magnetron sputtering 被引量:17
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作者 吕茂水 庞智勇 +2 位作者 修显武 戴瑛 韩圣浩 《Chinese Physics B》 SCIE EI CAS CSCD 2007年第2期548-552,共5页
Transparent and conducting zirconium-doped zinc oxide films with high transparency and relatively low resistivity have been successfully prepared by radio frequency (RF) msgnetron sputtering at room temperature, The... Transparent and conducting zirconium-doped zinc oxide films with high transparency and relatively low resistivity have been successfully prepared by radio frequency (RF) msgnetron sputtering at room temperature, The RF power is varied from 75 to 150 W. At first the crystallinity and conductivity of the film are improved and then both of them show deterioration with the increase of the RF power, The lowest resistivity achieved is 2.07 × 10^-3Ωcm at an RF power of 100W with a Hall mobility of 16cm^2V^-1s^-1 and a carrier concentration of 1.95 × 10^20 cm^-3. The films obtained are polycryetalline with a hexagonal structure and a preferred orientation along the c-axis, All the films have a high transmittance of approximately 92% in the visible range. The optical band gap is about 3.33 eV for the films deposited at different RF powers. 展开更多
关键词 SPUTTERING ZIRCONIUM zinc oxide transparent conducting films
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Three‑Dimensional Ordered Mesoporous Carbon Spheres Modified with Ultrafine Zinc Oxide Nanoparticles for Enhanced Microwave Absorption Properties 被引量:8
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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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Synthesis,Growth Mechanism,and Applications of Zinc Oxide Nanomaterials 被引量:4
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作者 Shulin JI Changhui YE 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 2008年第4期457-472,共16页
This article reviews recent progresses in growth mechanism, synthesis, and applications of zinc oxide nano-materials (mainly focusing on one-dimensional (1D) nanomaterials). In the first part of this article, we b... This article reviews recent progresses in growth mechanism, synthesis, and applications of zinc oxide nano-materials (mainly focusing on one-dimensional (1D) nanomaterials). In the first part of this article, we briefly introduce the importance, the synthesis methods and growth mechanisms, the properties and applications of ZnO 1D nanomaterials. In the second part of this article, the growth mechanisms of ZnO 1D nanomaterials will be discussed in detail in the framework of vapor-liquid-solid (VLS), vapor-solid (VS), and aqueous solution growth (ASG) approaches. Both qualitative and quantitative information will be provided to show how a controlled synthesis of ZnO 1D nanomaterials can be achieved. In the third part of this article, we present recent progresses in our group for the synthesis of ZnO 1D nanomaterials, and the results from other groups will only be mentioned briefly. Especially, experiment designing according to theories will be elaborated to demonstrate the concept of controlled synthesis. In the fourth part of this article, the properties and potential applications of ZnO 1D nanomaterials will be treated. Finally, a summary part will be presented in the fifth section. The future trend of research for ZnO 1D nanomaterials will be pointed out and key issues to be solved will be proposed. 展开更多
关键词 zinc Oxide ONE-DIMENSIONAL NANOMATERIALS Controlled synthesis
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Indium recovery from zinc oxide flue dust by oxidative pressure leaching 被引量:4
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作者 黎铉海 张燕娟 +2 位作者 覃全伦 阳健 韦岩松 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2010年第S1期141-145,共5页
Indium was recovered from zinc oxide flue dust(ZOFD)with sulfuric acid by oxidative pressure leaching in an autoclave, and the effects of different technological conditions on indium leaching were studied.Potassium pe... Indium was recovered from zinc oxide flue dust(ZOFD)with sulfuric acid by oxidative pressure leaching in an autoclave, and the effects of different technological conditions on indium leaching were studied.Potassium permanganate and hydrogen peroxide were used as oxidants.The atmospheric pressure leaching experiments were also carried out.The experimental results show that the leaching rate of indium can be effectively improved by oxidative pressure leaching.The optimum conditions of pressure leaching are determined as sulfuric 5.10 mol/L acid,leaching time 150 min,temperature 90℃,and the H2O2 dosage of 0.5 mL/g or 2.5%KMnO4.The leaching rate of indium is more than 90%,which is increased by 13%compared with that of atmospheric pressure leaching process without oxidant under the optimum conditions. 展开更多
关键词 INDIUM zinc oxide flue dust oxidative pressure leaching potassium permanganate hydrogen peroxide
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Carbothermic Reduction of Zinc Oxide Concentrate by Microwave 被引量:4
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作者 Ali Saidi Kamran Azari 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 2005年第5期724-728,共5页
Industrial application of microwave, as a heating source for material processing, was reviewed. The feasibility of carbothermic reduction of zinc oxide concentrate, as well as the effect of operating parameters was in... Industrial application of microwave, as a heating source for material processing, was reviewed. The feasibility of carbothermic reduction of zinc oxide concentrate, as well as the effect of operating parameters was investigated, using a home style microwave oven at 2.45 GHz. Zinc oxide concentrate does not effectively absorb microwave energy, while any source of carbon, which is used as the reduction agent, absorbs microwave energy very well. In this respect coke breeze was found to be the best, and thus, coke was used both as the reducing agent and the absorbent of microwave energy. It was also found that any increase in the carbon content and size, increases the reduction rate. Increasing the microwave power and the size of the sample could also increase the reduction rate. Further investigation shows that when zinc oxide is exposed to the microwave for some time, the rate of the reduction by conventional method increases. 展开更多
关键词 MICROWAVE zinc oxide REDUCTION
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Electrochemical Synthesis and Photocatalytic Property of Zinc Oxide Nanoparticles 被引量:4
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作者 Kodihalli G.Chandrappa Thimmappa V.Venkatesha 《Nano-Micro Letters》 SCIE EI CAS 2012年第1期14-24,共11页
Zinc oxide(ZnO) nanoparticles of varying sizes(20, 44 and 73 nm) have been successfully synthesized by a hybrid electrochemical-thermal method using aqueous sodium bicarbonate electrolyte and sacrificial Zn anode and ... Zinc oxide(ZnO) nanoparticles of varying sizes(20, 44 and 73 nm) have been successfully synthesized by a hybrid electrochemical-thermal method using aqueous sodium bicarbonate electrolyte and sacrificial Zn anode and cathode in an undivided cell under galvanostatic mode at room temperature. The as-synthesized product was characterized by X-ray diffraction(XRD), X-ray photoelectron spectra(XPS), Scanning electron microscopy along with Energy dispersive analysis of X-ray(SEM/EDAX), Transmission electron microscopy(TEM), Ultra Violet- Diffuse reflectance spectroscopic methods(UV-DRS). and UV-DRS spectral methods.The as-synthesized compound were single-crystalline and Rietveld refinement of calcined samples exhibited hexagonal(Wurtzite) structure with space group of P63mc(No.186). The band gaps for synthesized ZnO nanoparticles were 3.07, 3.12 and 3.13 e V, respectively, based on the results of diffuse reflectance spectra(DRS). The electrochemically synthesized ZnO powder was used as photocatalysts for UV-induced degradation of Methylene blue(MB). Photodegradation was also found to be function of exposure time and dye solution p H. It has been found that as-synthesized powder has excellent photocatalytic activity with 92% degradation of MB, indicating ZnO nanoparticles can play an important role as a semiconductor photocatalyst. 展开更多
关键词 zinc Oxide Methylene Blue Photocatalytic activity SEMICONDUCTOR
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Zinc extraction from zinc oxidized ore using(NH4)2SO4 roasting−leaching process 被引量:3
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作者 Xiao-yi Shen Hong-mei Shao +3 位作者 Ji-wen Ding Yan Liu Hui-min Gu Yu-chun Zhai 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2020年第11期1471-1481,共11页
An improved method of(NH4)2SO4 roasting followed by water leaching to utilize zinc oxidized ores was studied.The operating parameters were obtained by investigating the effects of the molar ratio of(NH4)2SO4 to zinc,r... An improved method of(NH4)2SO4 roasting followed by water leaching to utilize zinc oxidized ores was studied.The operating parameters were obtained by investigating the effects of the molar ratio of(NH4)2SO4 to zinc,roasting temperature,and holding time on zinc extraction.The roasting process followed the chemical reaction control mechanism with the apparent activation energy value of 41.74 kJ·mol^−1.The transformation of mineral phases in roasting was identified by X-ray diffraction analysis combined with thermogravimetry–differential thermal analysis curves.The water leaching conditions,including the leaching temperature,leaching time,stirring velocity,and liquid-to-solid ratio,were discussed,and the leaching kinetics was studied.The reaction rate was obtained under outer diffusion without product layer control;the values of the apparent activation energy for two stages were 4.12 and 8.19 kJ·mol^−1.The maximum zinc extraction ratio reached 96%while the efficiency of iron extraction was approximately 32%under appropriate conditions.This work offers an effective method for the comprehensive use of zinc oxidized ores. 展开更多
关键词 zinc oxidized ore ammonium sulfate roasting water leaching KINETICS MECHANISM extraction ratio
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Synthesis, characterization and biocompatibility studies of zinc oxide(ZnO) nanorods for biomedical application 被引量:3
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作者 R.Gopikrishnan K.Zhang +8 位作者 P.Ravichandran S.Baluchamy V.Ramesh S.Biradar P.Ramesh J.Pradhan J.C.Hall A.K.Pradhan G.T.Ramesh 《Nano-Micro Letters》 SCIE EI CAS 2010年第1期31-36,共6页
Nanoparticles are increasingly being recognized for their potential utility in biological applications including nanomedicine.Here,we have synthesized zinc oxide(ZnO)nanorods using zinc acetate and hexamethylenetetram... Nanoparticles are increasingly being recognized for their potential utility in biological applications including nanomedicine.Here,we have synthesized zinc oxide(ZnO)nanorods using zinc acetate and hexamethylenetetramine as precursors followed by characterizing using X-ray diffraction,fourier transform infrared spectroscopy,scanning electron microscopy and transmission electron microscopy.The growth of synthesized zinc oxide nanorods was found to be very close to its hexagonal nature,which is confirmed by X-ray diffraction.The nanorod was grown perpendicular to the long-axis and grew along the[001]direction,which is the nature of ZnO growth.The morphology of synthesized ZnO nanorods from the individual crystalline nucleus was confirmed by scanning and transmission electron microscopy.The length of the nanorod was estimated to be around 21 nm in diameter and 50 nm in length.Our toxicology studies showed that synthesized ZnO nanorods exposure on hela cells has no significant induction of oxidative stress or cell death even in higher concentration(10μg/ml).The results suggest that ZnO nanorods might be a safer nanomaterial for biological applications. 展开更多
关键词 zinc oxide [ZnO] NANORODS XRD SEM & TEM CYTOTOXICITY
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Production and characterization of ZnO nanoparticles and porous particles by ultrasonic spray pyrolysis using a zinc nitrate precursor 被引量:2
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作者 Burak Ebin Elif Arτg +1 位作者 Burak zkal Sebahattin Gürmen 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2012年第7期651-656,共6页
ZnO nanoparticles and porous particles were produced by an ultrasonic spray pyrolysis method using a zinc nitrate precursor at various temperatures under air atmosphere. The effects of reaction temperature on the size... ZnO nanoparticles and porous particles were produced by an ultrasonic spray pyrolysis method using a zinc nitrate precursor at various temperatures under air atmosphere. The effects of reaction temperature on the size and morphology of ZnO particles were investi- gated. The samples were characterized by energy dispersive spectroscopy, X-ray diffraction, transmission electron microscopy, and scanning electron microscopy. ZnO particles were obtained in a hexagonal crystal structure and the crystallite shapes changed from spherical to hex- agonal by elevating the reaction temperature. The crystallite size grew by increasing the temperature, in spite of reducing the residence time in the heated zone. ZnO nanoparticles were obtained at the lowest reaction temperature and ZnO porous particles, formed by aggregation of ZnO nanoparticles due to effective sintering, were prepared at higher temperatures. The results showed that the properties of ZnO particles can be controlled by changing the reaction temperature in the ultrasonic spray pyrolysis method. 展开更多
关键词 zinc oxide nanoparticles NANOCRYSTALLITES porous materials ultrasonic applications spray pyrolysis
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Recent progress of the native defects and p-type doping of zinc oxide 被引量:2
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作者 汤琨 顾书林 +3 位作者 叶建东 朱顺明 张荣 郑有炓 《Chinese Physics B》 SCIE EI CAS CSCD 2017年第4期27-49,共23页
Zinc oxide(ZnO) is a compound semiconductor with a direct band gap and high exciton binding energy.The unique property,i.e.,high efficient light emission at ultraviolet band,makes ZnO potentially applied to the shor... Zinc oxide(ZnO) is a compound semiconductor with a direct band gap and high exciton binding energy.The unique property,i.e.,high efficient light emission at ultraviolet band,makes ZnO potentially applied to the short-wavelength light emitting devices.However,efficient p-type doping is extremely hard for ZnO.Due to the wide band gap and low valence band energy,the self-compensation from donors and high ionization energy of acceptors are the two main problems hindering the enhancement of free hole concentration.Native defects in ZnO can be divided into donor-like and acceptorlike ones.The self-compensation has been found mainly to originate from zinc interstitial and oxygen vacancy related donors.While the acceptor-like defect,zinc vacancy,is thought to be linked to complex shallow acceptors in group-VA doped ZnO.Therefore,the understanding of the behaviors of the native defects is critical to the realization of high-efficient p-type conduction.Meanwhile,some novel ideas have been extensively proposed,like double-acceptor co-doping,acceptor doping in iso-valent element alloyed ZnO,etc.,and have opened new directions for p-type doping.Some of the approaches have been positively judged.In this article,we thus review the recent(2011-now) research progress of the native defects and p-type doping approaches globally.We hope to provide a comprehensive overview and describe a complete picture of the research status of the p-type doping in ZnO for the reference of the researchers in a similar area. 展开更多
关键词 zinc oxide native defects p-type doping ACCEPTOR
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