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Effects of site preparation methods on soil physical properties and outplanting success of coniferous seedlings in boreal forests
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作者 Aleksey S.Ilintsev Elena N.Nakvasina Alexander P.Bogdanov 《Journal of Forestry Research》 SCIE EI CAS CSCD 2024年第2期70-80,共11页
This study assessed the effect of patch scarification and mounding on the physical properties of the root layer and the success of tree planting in various types of forests.This study was conducted on 12 forest sites ... This study assessed the effect of patch scarification and mounding on the physical properties of the root layer and the success of tree planting in various types of forests.This study was conducted on 12 forest sites in taiga forests of the European part of Russia.A total of 54 plots were set up to assess seedling survival;root collar diameter,height,and heigh increment were measured for 240 seedlings to assess growth.In the rooting layer,240 soil samples were taken to determine physical properties.The study showed that soil treatment methods had no effect on bulk density and total porosity in Cladina sites.However,reduced soil moisture was noted,particularly in mounds,resulting in increased aeration.In Myrtillus sites,there were increased bulk density,reduced soil moisture,and total porosity in the mounds.Mounding treatment in Polytrichum sites resulted in reduced soil moisture and increased aeration porosity.In the Myrtillus and Polytrichum sites,patch scarification had no effects on physical properties.In Polytrichum sites,survival rates,heights,and heigh increments of bareroot Norway spruce seedlings in mounds were higher than in patches;however,the same did not apply to diameter.In Cladina and Myrtillus sites,there was no difference in growth for bareroot and containerised seedlings with different soil treatments.Growing conditions and soil types should be considered when applying different soil treatment methods to ensure high survival rates and successful seedling growth. 展开更多
关键词 Boreal forests Mechanical site preparation Patch scarification MOUNDING Soil properties Containerised seedlings Bareroot seedlings
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Holistic and localized preparation methods for triboelectric sensors:principles,applications and perspectives
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作者 Zhenqiu Gao Shaokuan Wu +6 位作者 Yihan Wei Mervat Ibrahim Hani Nasser Abdelhamid Guyu Jiang Jun Cao Xuhui Sun Zhen Wen 《International Journal of Extreme Manufacturing》 SCIE EI CAS CSCD 2024年第5期20-36,共17页
With the arrival of intelligent terminals,triboelectric nanogenerators,as a new kind of energy converter,are considered one of the most important technologies for the next generation of intelligent electronics.As a se... With the arrival of intelligent terminals,triboelectric nanogenerators,as a new kind of energy converter,are considered one of the most important technologies for the next generation of intelligent electronics.As a self-powered sensor,it can greatly reduce the power consumption of the entire sensing system by transforming external mechanical energy to electricity.However,the fabrication method of triboelectric sensors largely determines their functionality and performance.This review provides an overview of various methods used to fabricate triboelectric sensors,with a focus on the processes of micro-electro-mechanical systems technology,three-dimensional printing,textile methods,template-assisted methods,and material synthesis methods for manufacturing.The working mechanisms and suitable application scenarios of various methods are outlined.Subsequently,the advantages and disadvantages of various methods are summarized,and reference schemes for the subsequent application of these methods are included.Finally,the opportunities and challenges faced by different methods are discussed,as well as their potential for application in various intelligent systems in the Internet of Things. 展开更多
关键词 triboelectric sensor fabrication methods intelligent system holistic-to-localized
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Efficient Preparation and Electrochemical Properties of BiOCl/Graphite by One-step Solvothermal Method
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作者 门丽娟 FEI Chi +3 位作者 LIU An 陈春钰 ZHOU Jiankang JU Dianchun 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS CSCD 2024年第3期651-657,共7页
We used the surface-pretreated graphite paper(Gp)as a carrier and loaded BiOCl with high selectivity to Cl^(-)on its surface by solvothermal method to form BiOCl@Gp electrode.The morphology,structure,and composition o... We used the surface-pretreated graphite paper(Gp)as a carrier and loaded BiOCl with high selectivity to Cl^(-)on its surface by solvothermal method to form BiOCl@Gp electrode.The morphology,structure,and composition of the materials were characterized by scanning electron microscopy and nitrogen adsorption/desorption,and the results showed that the spherical BiOCl particles were uniformly dispersed on the surface of the Gp,forming a mesoporous BiOCl@Gp composite with a specific surface area of 22.82 m^(2)/g and a pore volume of 0.043 cm3/g.Furthermore,cyclic voltammetry and electrochemical impedance spectroscopy were used to test the electrochemical properties of the composites,and the stability of BiOCl and the high conductivity of Gp were synergistic,the BiOCl@Gp exhibited a specific capacitance of 30.2 F·g^(-1) at a current density of 0.5 A·g^(-1),and the selectivity of the BiOCl@Gp materials for Cl^(-)was significantly higher than that of SO_(4)^(2-),NO_(2)^(-),and HCO_(3)^(-).Therefore,BiOCl@Gp composite electrode materials can be used for the selective adsorption of Cl^(-)in wastewater,in order to achieve efficient wastewater recycling. 展开更多
关键词 solvothermal method bismuth oxychloride ELECTROCHEMISTRY electrode materials
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Optimization of Preparation of Oregano Oil Microspheres by Box-Behnken Response Surface Methodology
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作者 Fei HAN Mengyao TU +5 位作者 Hui YANG Hekun DUAN Fuhao HU Xinli LIANG Yang GUAN Wei XU 《Medicinal Plant》 2024年第4期40-45,共6页
[Objectives]To optimize the formulation and preparation of oregano oil microspheres by Box-Behnken response surface methodology.[Methods]Chitosan was used as the carrier material to prepare oregano oil microspheres by... [Objectives]To optimize the formulation and preparation of oregano oil microspheres by Box-Behnken response surface methodology.[Methods]Chitosan was used as the carrier material to prepare oregano oil microspheres by emulsion crosslinking method.The encapsulation efficiency,drug loading and ID 50 were used as the evaluation indicators,and the comprehensive score(OD)obtained by"coefficient of variation-AHP comprehensive weighting method"was used as the final evaluation indicator.The formulation design and preparation process were optimized by single factor experiment and Box-Behnken response surface methodology,and the optimal process parameters were determined.[Results]The optimal formulation and preparation process parameters of oregano oil microspheres were as follows:the ratio of oregano oil to chitosan was 2∶1,the emulsifying speed of double emulsion was 200 r/min,the amount of emulsifier in the colostrum was 4%,and the volume of curing agent was 1.0 mL.The average encapsulation efficiency was 45.33%±1.32%,the average drug loading was 30.59%±2.45%,and the median diameter(ID 50)was 52.596μm±0.023%.[Conclusions]The encapsulation efficiency,drug loading and ID 50 of oregano oil chitosan microspheres prepared by emulsion crosslinking method met the requirements.The drug-loaded microsphere not only can be used as a preparation finished product for direct application,but also be used as a product intermediate to lay a foundation for the research and development of subsequent dosage forms. 展开更多
关键词 Oregano oil CHITOSAN MICROSPHERES preparation Response surface methodology(RSM)
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Preparation for CSST:Star-galaxy Classification using a Rotationally Invariant Supervised Machine Learning Method
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作者 Shiliang Zhang Guanwen Fang +6 位作者 Jie Song Ran Li Yizhou Gu Zesen Lin Chichun Zhou Yao Dai Xu Kong 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2024年第9期136-146,共11页
Most existing star-galaxy classifiers depend on the reduced information from catalogs,necessitating careful data processing and feature extraction.In this study,we employ a supervised machine learning method(GoogLeNet... Most existing star-galaxy classifiers depend on the reduced information from catalogs,necessitating careful data processing and feature extraction.In this study,we employ a supervised machine learning method(GoogLeNet)to automatically classify stars and galaxies in the COSMOS field.Unlike traditional machine learning methods,we introduce several preprocessing techniques,including noise reduction and the unwrapping of denoised images in polar coordinates,applied to our carefully selected samples of stars and galaxies.By dividing the selected samples into training and validation sets in an 8:2 ratio,we evaluate the performance of the GoogLeNet model in distinguishing between stars and galaxies.The results indicate that the GoogLeNet model is highly effective,achieving accuracies of 99.6% and 99.9% for stars and galaxies,respectively.Furthermore,by comparing the results with and without preprocessing,we find that preprocessing can significantly improve classification accuracy(by approximately 2.0% to 6.0%)when the images are rotated.In preparation for the future launch of the China Space Station Telescope(CSST),we also evaluate the performance of the GoogLeNet model on the CSST simulation data.These results demonstrate a high level of accuracy(approximately 99.8%),indicating that this model can be effectively utilized for future observations with the CSST. 展开更多
关键词 methods:data analysis techniques:image processing stars:imaging
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Preparation of α-High Strength Gypsum from Flue Gas Desulfurization Gypsum Pretreated by Hydrothermal-aging Method
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作者 苏一鑫 GAO Lili +3 位作者 陈学青 LI Zhishui 李雲 CAO Jilin 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS CSCD 2024年第1期75-81,共7页
The synthesis of α-calcium sulfate hemihydrate (α-CSH) from flue gas desulfurization (FGD)gypsum is a good way to realize the comprehensive utilization of FGD gypsum. To obtainα-CSH with the satisfactory performanc... The synthesis of α-calcium sulfate hemihydrate (α-CSH) from flue gas desulfurization (FGD)gypsum is a good way to realize the comprehensive utilization of FGD gypsum. To obtainα-CSH with the satisfactory performances, a facile hydrothermal-aging pretreatment process for FGD gypsum raw materials was proposed, where FGD gypsum was firstly hydrothermally converted to α-CSH whiskers, and α-CSH whiskers were further hydrated to synthesize CaSO4·2H2O (CSD) by aging under the regulation of N,N'-methylenebisacrylamide (MBA). The effects of aging time, MBA addition, aging temperature, and pH on the morphology of the synthesized CSD were investigated. The synthesized CSD crystals exhibit highly uniform prismatic morphology with the length of ca 100μm and the whiteness of 91.56%. The regulation mechanism of MBA was also illustrated. The synthesized CSD crystals with prismatic morphology were further used as raw materials to synthesize the short columnar α-CSH. The absolute dry compressive strength of paste prepared from the short columnar α-CSH is 40.85 MPa, which reaches α40 strength grade. 展开更多
关键词 flue gas desulphurization gypsum α-calcium sulfate hemihydrate hydrothermal-aging method N N'-methylenebisacrylamide prismatic CSD
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Bowel preparation before colonoscopy: Consequences, mechanisms, and treatment of intestinal dysbiosis
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作者 Ze-Long Zheng Qing-Fan Zheng +1 位作者 Li-Qiang Wang Yi Liu 《World Journal of Gastroenterology》 SCIE CAS 2025年第2期13-26,共14页
The term“gut microbiota”primarily refers to the ecological community of various microorganisms in the gut,which constitutes the largest microbial community in the human body.Although adequate bowel preparation can i... The term“gut microbiota”primarily refers to the ecological community of various microorganisms in the gut,which constitutes the largest microbial community in the human body.Although adequate bowel preparation can improve the results of colonoscopy,it may interfere with the gut microbiota.Bowel preparation for colonoscopy can lead to transient changes in the gut microbiota,potentially affecting an individual’s health,especially in vulnerable populations,such as patients with inflammatory bowel disease.However,measures such as oral pro-biotics may ameliorate these adverse effects.We focused on the bowel prepa-ration-induced changes in the gut microbiota and host health status,hypothesized the factors influencing these changes,and attempted to identify measures that may reduce dysbiosis,thereby providing more information for individualized bowel preparation for colonoscopy in the future. 展开更多
关键词 Bowel preparation COLONOSCOPY MICROBIOTA Inflammatory bowel disease PROBIOTICS
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Insight Into the Separation-of-Variable Methods for the Closed-Form Solutions of Free Vibration of Rectangular Thin Plates
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作者 Yufeng Xing Ye Yuan Gen Li 《Computer Modeling in Engineering & Sciences》 SCIE EI 2025年第1期329-355,共27页
The separation-of-variable(SOV)methods,such as the improved SOV method,the variational SOV method,and the extended SOV method,have been proposed by the present authors and coworkers to obtain the closed-form analytica... The separation-of-variable(SOV)methods,such as the improved SOV method,the variational SOV method,and the extended SOV method,have been proposed by the present authors and coworkers to obtain the closed-form analytical solutions for free vibration and eigenbuckling of rectangular plates and circular cylindrical shells.By taking the free vibration of rectangular thin plates as an example,this work presents the theoretical framework of the SOV methods in an instructive way,and the bisection–based solution procedures for a group of nonlinear eigenvalue equations.Besides,the explicit equations of nodal lines of the SOV methods are presented,and the relations of nodal line patterns and frequency orders are investigated.It is concluded that the highly accurate SOV methods have the same accuracy for all frequencies,the mode shapes about repeated frequencies can also be precisely captured,and the SOV methods do not have the problem of missing roots as well. 展开更多
关键词 Separation-of-variable method Rayleigh quotient nodal line eigenvalue equation bisection method
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Highly Defective Dark TiO_(2) Modified with Pt: Effects of Precursor Nature and Preparation Method on Photocatalytic Properties
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作者 E.D.Fakhrutdinova O.A.Reutova +6 位作者 T.A.Bugrova I.Yu.Ovsyuk L.S.Kibis O.A.Stonkus D.B.Vasilchenko O.V.Vodyankina V.A.Svetlychnyi 《Transactions of Tianjin University》 EI CAS 2024年第2期198-209,共12页
The study focused on the modification with platinum of dark defective titania obtained via pulsed laser ablation. Both the method of Pt introduction and the nature of the Pt precursor were varied. All samples exhibite... The study focused on the modification with platinum of dark defective titania obtained via pulsed laser ablation. Both the method of Pt introduction and the nature of the Pt precursor were varied. All samples exhibited similar phase compositions, specific surface areas, and Pt contents. High-resolution transmission electron microscopy coupled with pulsed CO adsorption revealed increased dispersity when photoreduction and the hydroxonitrate complex (Me _(4) N) _(2) [Pt _(2) (OH) _(2) (NO _(3) ) _(8) ] were used. The sample featured a high content of single-atom species and subnano-sized Pt clusters. The X-ray photoelectron spectroscopy results showed that the photoreduction method facilitated the appearance of a larger number of Pt ^(2+) states, which appeared owing to the strong metal-support interaction (SMSI) eff ect of the transfer of electron density from the electron-saturated defects on the TiO _(2) surface to Pt ^(4+) . In the hydrogen evolution reaction, samples with a significant fraction of the Pt ^(2+) ionic component, capable of generating short-lived Pt^(0) single-atom sites under irradiation due to the SMSI eff ect, exhibited the highest photocatalytic activity. The 0.5Pt(C)/TiO_(2) -Ph sample exhibited the highest hydrogen yield with a quantum efficiency of 0.53, retaining its activity even after 8 h of operation. 展开更多
关键词 Dark(black)TiO_(2) Pulsed laser ablation Platinum reduction method Precursor type PHOTOCATALYSIS Hydrogen evolution reaction
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Study on Preparation of Cathode Material of Lithium Iron Phosphate Battery by Self-Craning Thermal Method
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作者 Maosen Pan Yali Ge Bo-hao Lin 《Journal of Electronic Research and Application》 2024年第6期194-199,共6页
The cathode material of carbon-coated lithium iron phosphate(LiFePO4/C)lithium-ion battery was synthesized by a self-winding thermal method.The material was characterized by X-ray diffraction(XRD)and scanning electron... The cathode material of carbon-coated lithium iron phosphate(LiFePO4/C)lithium-ion battery was synthesized by a self-winding thermal method.The material was characterized by X-ray diffraction(XRD)and scanning electron microscope(SEM).The electrochemical properties of LiFePO4/C materials were measured by the constant current charge-discharge method and cyclic voltammetry.The results showed that the LiFePO4/C material prepared by the self-propagating heat method has a typical olivine crystal structure,and the product had fine grains and good electrochemical properties.The optimal sintering temperature is 700℃,the sintering time is 24 h,the particle size of the lithium iron phosphate material is about 300 nm,and the maximum discharge capacity is 121 mAh/g at 0.1 C rate. 展开更多
关键词 BATTERY Cathode material Lithium iron phosphate Autocratic heat method
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Structural Modal Parameter Recognition and Related Damage Identification Methods under Environmental Excitations: A Review
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作者 Chao Zhang Shang-Xi Lai Hua-Ping Wang 《Structural Durability & Health Monitoring》 EI 2025年第1期25-54,共30页
Modal parameters can accurately characterize the structural dynamic properties and assess the physical state of the structure.Therefore,it is particularly significant to identify the structural modal parameters accordi... Modal parameters can accurately characterize the structural dynamic properties and assess the physical state of the structure.Therefore,it is particularly significant to identify the structural modal parameters according to the monitoring data information in the structural health monitoring(SHM)system,so as to provide a scientific basis for structural damage identification and dynamic model modification.In view of this,this paper reviews methods for identifying structural modal parameters under environmental excitation and briefly describes how to identify structural damages based on the derived modal parameters.The paper primarily introduces data-driven modal parameter recognition methods(e.g.,time-domain,frequency-domain,and time-frequency-domain methods,etc.),briefly describes damage identification methods based on the variations of modal parameters(e.g.,natural frequency,modal shapes,and curvature modal shapes,etc.)and modal validation methods(e.g.,Stability Diagram and Modal Assurance Criterion,etc.).The current status of the application of artificial intelligence(AI)methods in the direction of modal parameter recognition and damage identification is further discussed.Based on the pre-vious analysis,the main development trends of structural modal parameter recognition and damage identification methods are given to provide scientific references for the optimized design and functional upgrading of SHM systems. 展开更多
关键词 Structural health monitoring data information modal parameters damage identification AI method
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Effect of preparation methods on the adsorption property of municipal solid waste-based carbon materials 被引量:1
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作者 宋敏 唐心红 +1 位作者 唐美 卫月星 《Journal of Southeast University(English Edition)》 EI CAS 2016年第2期208-214,共7页
Three different preparation methods including steam physical activation, catalytic carbonation and KOH chemical activation methods were used to prepare municipal solid waste- based carbon materials. The methylene blue... Three different preparation methods including steam physical activation, catalytic carbonation and KOH chemical activation methods were used to prepare municipal solid waste- based carbon materials. The methylene blue (MB) adsorption value was applied to evaluate the adsorption capabilities of the prepared carbon materials. The effects of preparation methods on adsorption capability and yield of products were investigated. The yield of carbon materials with the catalytic carbonation method is the highest, and the KOH activation method is the second level. Considering the adsorption performance, the KOH activation method is much more favorable. Among the different components of municipal solid waste-based carbon materials, the adsorption properties of the single component of paperboard, the double components of tire and paperboard, the triple components of tire, paperboard and polyvinyl chloride (PVC), and the multi-component mixtures are better than those of other single-, double-, triple- and multi-component mixtures, respectively. 展开更多
关键词 PYROLYSIS preparation methods WASTE ADSORPTION activated carbon
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Preparation of TiC powders by carbothermal reduction method in vacuum 被引量:21
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作者 森维 徐宝强 +4 位作者 杨斌 孙红燕 宋建勋 万贺利 戴永年 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2011年第1期185-190,共6页
The preparation of fine TiC powders by carbothermal reduction of TiO2 in vacuum was investigated by XRD,SEM,XRF and laser particle sizer.Thermodynamic analysis indicates that it is easy to prepare TiC in vacuum and th... The preparation of fine TiC powders by carbothermal reduction of TiO2 in vacuum was investigated by XRD,SEM,XRF and laser particle sizer.Thermodynamic analysis indicates that it is easy to prepare TiC in vacuum and the formation sequence of products are Ti4O7(Magneli phase),Ti3O5,Ti2O3,TiCxO1-x and TiC with the increase of reaction temperature.Experimental results demonstrate that TiC powders with single phase are obtained with molar ratio of TiO2 to C ranging from 1:3.2 to 1:6 at 1 550 ℃ for 4 h when the system pressure is 50 Pa,and TiC1.0 is gained when the molar ratio of TiO2 to C is 1:4 and 1:5.In addition,fine TiC1.0 powders(D50 equals 3.04 μm) with single phase and low impurities are obtained when the molar ratio of TiO2 to C is 1:4.SEM observation shows that uniform shape,low agglomeration,and loose structure are observed on the surface of block product. 展开更多
关键词 titanium dioxide titanium carbide VACUUM carbothermal reduction method
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Preparation and Adsorption Properties of Activated Carbon from Glutinous Rice Straw by KOH Method 被引量:2
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作者 梁健 蔡勤 +5 位作者 李波 吴昌演 刘汉林 程静 周健齐 柏松 《Agricultural Science & Technology》 CAS 2015年第11期2549-2551,2567,共4页
[Objective] This study aimed to improve comprehensive utilization value of glutinous rice straw and to develop new raw material for preparation of activated carbon. [Method] Using potassium hydroxide as activator and ... [Objective] This study aimed to improve comprehensive utilization value of glutinous rice straw and to develop new raw material for preparation of activated carbon. [Method] Using potassium hydroxide as activator and glutinous rice straw as raw material, activated carbon was prepared. [Result] The optimum technological conditions for preparation of activated carbon from glutinous rice straw were as fol- lows: activator concentration of 2 mol/L, activation time of 60 min, activation tem- perature of 600 ℃ and carbonization temperature of 450℃. The adsorption values of methylene blue and iodine by activated carbon prepared from glutinous rico straw were 10.21 ml/0.1 g and 920.74 mg/g respectively under the optimal conditions. The quality of the prepared activated carbon met the grade two of water quality purifica- tion-using activated carbon quality standard. [Conclusion] This study will provide certain references for comprehensive utilization of glutinous rice straw and preparation of high-performance activated carbon. 展开更多
关键词 Glutinous rice straw Activated carbon ABSORBENT preparation
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Preparation of V-Ti-Fe master alloys by metallothermic reduction method 被引量:5
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作者 王斌 刘奎仁 +2 位作者 陈建设 高腾跃 何季麟 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2012年第6期1507-1512,共6页
V-Ti-Fe master alloys were prepared by metaUothermic reduction method, and the influences of the mass ratio of V205 to TiO2, Al and Al-Mg alloy addition amounts on the metal recovery rates and alloy compositions were ... V-Ti-Fe master alloys were prepared by metaUothermic reduction method, and the influences of the mass ratio of V205 to TiO2, Al and Al-Mg alloy addition amounts on the metal recovery rates and alloy compositions were investigated. The results show that appropriate technological parameters are: the mass ratio of V205 to TiO2 is 0.5:1, Al addition represents 95% of the theoretical value, and the Al-Mg alloy addition amount is one third that of the Al addition. The results from energy spectrum analysis show that V and Fe distribute uniformly in the prepared alloy, while the segregation for Ti, i.e. Ti-rich phase is detected. A spray refming process was carried out to reduce the impurity contents of Al and O in the prepared alloys. The Al content drops from 4.27% to 1.86%, and the O content drops from 2.10% to 0.91% after the refining process. 展开更多
关键词 V-Ti-Fe master alloys metallothermic reduction method recovery rates refining process
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Preparation of long alumina fibers by sol-gel method using malic acid 被引量:11
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作者 谭宏斌 郭从盛 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2011年第7期1563-1567,共5页
The precursor sol of alumina was prepared by sol-gel method with aluminum nitrate and malic acid as raw materials.The effects of content of malic acid and polyvinylpyrrolidone (PVP) on sol spinnability were explored... The precursor sol of alumina was prepared by sol-gel method with aluminum nitrate and malic acid as raw materials.The effects of content of malic acid and polyvinylpyrrolidone (PVP) on sol spinnability were explored.The gel fibers with above 80 cm in length were obtained by mixing aluminum nitrate,malic acid and PVP on mass ratio of 10 3 1.5.Thermogravimetry-differential scanning calorimetry (TG-DSC),Fourier transform infrared (FTIR) spectrum,X-ray diffractometry (XRD),and scanning electron microscopy (SEM) were used to characterize the properties of the gel and ceramic fibers.The alumina fibers with a smooth surface and about 20μm in diameter were obtained by sintering at 1 200℃,and their main phase was indentified to be α-Al2O3. 展开更多
关键词 AL2O3 long fiber sol-gel method POLYVINYLPYRROLIDONE
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A novel wet-chemical method for preparation of silver flakes 被引量:4
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作者 翟爱霞 蔡雄辉 杜斌 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2014年第5期1452-1457,共6页
A novel wet-chemical method for the preparation of silver flakes was studied. The well-defined particles were prepared by directly adding FeSO4 solution into AgNO3 solution containing citric acid at an agitation speed... A novel wet-chemical method for the preparation of silver flakes was studied. The well-defined particles were prepared by directly adding FeSO4 solution into AgNO3 solution containing citric acid at an agitation speed of 150 r/min at room temperature. The products were characterized by scanning electron microscopy (SEM) and X-ray diffraction (XRD). The results show that particles are irregular thin silver flakes. And the sizes of them range from 2 to 10 μm. It is found that citric acid plays an important role in the formation of sliver flakes. There is an optimum amount of citric acid for the preparation of silver flakes by this method. It is also found that high reduction rate is favorable for the formation of silver flakes. 展开更多
关键词 silver flake wet-chemical method FeSO4·7H2O citric acid
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Preparation and Characterization of Nanometer TiO_2 by Hydrolysis Precipitation Method 被引量:1
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作者 方世杰 徐明霞 +1 位作者 郝俊杰 汪成建 《Transactions of Tianjin University》 EI CAS 2002年第2期79-82,共4页
Nanometer TiO 2 powders were obtained from TiOSO 4 and studied by XRD, TEM and BET. The result indicated that pH and heat treatment temperature have great effects on their grain size and crystal phase structu... Nanometer TiO 2 powders were obtained from TiOSO 4 and studied by XRD, TEM and BET. The result indicated that pH and heat treatment temperature have great effects on their grain size and crystal phase structure. Annealed at 500 ℃, nanometer TiO 2 with a specific surface area of 101.39 m 2 ·g -1 and a grain size about 10 nm were obtained(pH=5); and with a specific surface area of 95.48 m 2 ·g -1 and a grain size about 30 nm were obtained(pH=10). The research indicated that crystal phase transformation of rutile at 750 ℃made great promotion in grain size growth. 展开更多
关键词 nanometer Tio 2 hydrolysis precipitation method PH crystal phase transformation
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Preparation of Cu nanoparticles with ascorbic acid by aqueous solution reduction method 被引量:7
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作者 刘清明 Takehiro YASUNAMI +1 位作者 Kensuke KURUDA Masazumi OKIDO 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2012年第9期2198-2203,共6页
Cu nanoparticles were prepared by reducing Cu2+ ions with ascorbic acid through aqueous solution reduction method. The effects of solution pH and average size of Cu2O particles on the preparation of Cu nanoparticles ... Cu nanoparticles were prepared by reducing Cu2+ ions with ascorbic acid through aqueous solution reduction method. The effects of solution pH and average size of Cu2O particles on the preparation of Cu nanoparticles were investigated. Cu particles were prepared at pH 3, 5 or 7, with the smallest Cu particles obtained at pH 7. However, Cu particles could not be prepared at pH 9 or 11. The average size of Cu2O particles can affect that of Cu particles. Larger Cu2O particles result in larger Cu particles. In addition, experiments were conducted to explore the reaction process by measuring the X-ray diffraction (XRD) patterns of specimens collected at different time points during the reaction. It was found that Cu(OH)2 was initially formed as a precursor, followed by the formation of Cu2O, which was finally reduced to Cu particles. 展开更多
关键词 Cu nanoparticles aqueous solution reduction method ascorbic acid intermediate product
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Exploration of Methods for Preparation of Cattle Eyeball Paraffin Sections 被引量:1
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作者 邓立新 郭延俭 +4 位作者 王绿林 王朝阳 董海聚 李杨 贺丛 《Agricultural Science & Technology》 CAS 2014年第1期71-73,共3页
[Objective] This study aimed to establish a new method for preparing paraffin sections of cattle eyebal s. [Method] The conventional method was used to prepare paraffin sections for cattle eyebal s in the control and ... [Objective] This study aimed to establish a new method for preparing paraffin sections of cattle eyebal s. [Method] The conventional method was used to prepare paraffin sections for cattle eyebal s in the control and a new method termed&quot;opening a window on cornea and refixation&quot; was used to prepare paraffin sections for cattle eyebal s in the treatment group. [Result] After the prepared specimens in the treatment group were fixed, it could be macroscopical y observed that retina and choroid were closely connected, with detachment occurring at a smal portion be-tween the two. According to the paraffin sections, it was microscopical y observed that the continuity of trabecular meshwork was intact, as wel as the continuity be-tween different layers of eyebal wal , without detachment between them, no retinal detachment, no shrinkage of each layer of tissue cells. [Conclusion] This study pro-vides a foundation for the basic research and pathological study of eyebal s. 展开更多
关键词 CATTLE EYEBALL Paraffin sections "Opening a window on cornea andrefixation" method
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