检索结果-南通市图书馆

CuO-modified activated carbon for the improvement of toluene removal in air

Journal of Environmental Sciences 2020年第2期32卷 122-132页

作者： Bingman Lei Biyan Liu Huijun Zhang Libei Yan Hongmei Xie Guilin Zhou engineering research center for Waste Oil Recovery technology and Equipment Ministry of EducationChongqing Technology and Business UniversityChongqing 400067China chongqing Feearth Environmental technology Co. Ltd.Chongqing 400067China Department of Materials Science and engineering Chongqing Technology and Business UniversityChongqing 400067China

We used an impregnation method to prepare CuO/AC(activated carbon) composite materials of different CuO content and characterized them via scanning electron microscope(SEM), Brunauer–Emmett–Teller(BET), and Fourier transform infrared spectroscopy(FT-IR).The effect of CuO content on toluene adsorption/desorption was *** explored the reusability of AC and AC03(CuO modified AC with CuO loading 0.3 wt.%) adsorbents via toluene adsorption/desorption cycle *** used quasi-firstand quasi-second-order models, the Bangham model, and the Weber–Morris model to fit the toluene adsorption *** introduction of CuO species evidently improved the adsorption performance of activated carbon toward *** CuO content markedly affected the specific surface area, CuO dispersal, the numbers of oxygen-containing functional groups on the surface, and adsorption performance of the prepared composite *** CuO content was not favorable for the formation of active adsorption sites,while high content greatly reduced the specific surface area, and even covered active adsorption *** toluene adsorption performance varied in the order AC03 > AC02 >AC05 > AC08 > AC01(AC03, AC02, AC05, AC08 and AC01 are CuO modifying AC with CuO loading 0.3, 0.2, 0.5 0.8 and 0.1 wt.%, respectively).The breakthrough time and toluene adsorption capacity of the AC03 composite adsorbent were 94 min and 701.8 mg/g,respectively, and the recycling efficiency was 92.8% after thermal desorption at 200°*** adsorption process was best described by the Bangham model and adsorption could be divided into three stages.

关键词： CuO modified activated carbon composite adsorbents CuO species Toluene Adsorptive removal

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Spectroscopic properties of Gd_2O_3:Dy^(3+)nanocrystals

引用

Journal of Rare Earths 2013年第3期31卷 235-240页

作者：彭玲玲韩涛陈慧张铁军 chongqing Key Laboratory of Micro/Nano Materials engineering and technology Research Center for Material Interdisciplinary ScienceChongqing University of Arts and Science

Gd203：Dy3＋ nanocrystals were synthesized via solvothermal method followed by a subsequent calcination. The samples were characterized by X-ray diffraction （XRD）, transmission electron microsopy （TEM）, Electronic dispersive X-ray spectroscopy （EDX）, photoluminescence （PL） spectrum and decay curves. The effect of the annealing temperature on the crystallinity and particle size was studied; heat treatment improved the crystallinity of as-prepared nanocrystals as well as increased their particle size. The nanocryatals presented monodispersed spherical shape under TEM. Photoluminescence spectra showed that nanocrystal exhibited strong yellow emission corresponding to 4F9/2----6HI3/2 transition （573 nm） of Dy3＋ under UV light excitation, which broadened with the particle size decreased without structure changed. The theoretical mechanism of luminescence was explored and surface effect was thought to be the main reason.

关键词： gadolinium oxides nanocrystal photoluminescence surface effect rare earths

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Achieving exceptionally high strength and rapid degradation rate of Mg-Er-Ni alloy by strengthening with lamellar γ' and bulk LPSO phases

引用

Journal of Materials Science & technology 2024年第1期168卷 88-102页

作者： Chaoneng Dai Jingfeng Wang Yuanlang Pan Kai Ma Yinhong Peng Ye Wang Danqian Wang Chunhua Ran Jinxing Wang Yanlong Ma College of Chemistry and Chemical engineering Chongqing UniversityChongqing 401331China College of Materials Science and engineering Chongqing UniversityChongqing 400044China National engineering research center for Magnesium Alloys Chongqing 400044China College of Materials Science and engineering Chongqing University of TechnologyChongqing 400054China

As-extruded Mg-Er-Ni alloys with different volume fractions of long-period stacking ordered(LPSO)phase and density of lamellar γ' phase were prepared,and the microstructure,mechanical,and degradation properties were *** the bulk LPSO phase and the lamellar γ' phase,and controlling the dynamic recrystallization processes during deformation by adjusting the volume fraction of LPSO and the density of the γ' phase,a synergistic increase in strength and degradation rate can be *** the one hand,the increase in corrosion rate was related to the increased volume fraction of the bulk LPSO phase and the densities of the lamellar γ' phase,which provide more galvanic ***,high densities of the lamellar γ' phase can provide more corrosion interface by inhibiting the recrystallization process to refine dynamic recrystallized(DRXed)grains during the hot *** the other hand,the ultimate tensile strength(UTS)and tensile yield strength(TYS)of the Mg-Er-Ni alloy increased from 345 and 265 MPa to 514 MPa and 358 MPa,respectively,which was mainly attributed to grain boundary and texture strengthening,bulk LPSO phase and lamellar γ' phase ***,Mg^(-1)4Er-4Ni alloy,which contains the highest volume fraction bulk LPSO phase and the densities of lamellar γ' phase,re-alized a synergistic enhancement of strength and degradation *** UTS,TYS,and degradation rate of Mg^(-1)4Er-4Ni were 514 MPa,358 MPa,and 142.5 mg cm^(-2)h^(-1)(3 wt%KCl solution at 93◦C),*** research provides new insight into developing Mg alloys with high strength and degradation rates for fracturing tool materials in the application of oil and gas exploitation in harsh environments.

关键词： Mg-Er-Ni alloy Lamellarγ'and bulk LPSO phases Rapid degradation rate High strength Mechanical and corrosion mechanism

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Enhanced ductility of Mg–3Al–1Zn alloy reinforced with short length multiwalled carbon nanotubes using a powder metallurgy method

引用

Progress in Natural Science:Materials International 2015年第4期25卷 276-281页

作者： Muhammad Rashad Fusheng Pan Muhammad Asif Li Li College of Materials Science and engineering Chongqing University National engineering research center for Magnesium Alloys Chongqing University chongqing Academy of Science and technology School of Materials Science and engineering Dalian University of Technology

Mg–3Al–1Zn–CNTs composites, with different weight fractions(0.25–1.0 wt%) of carbon nanotubes(CNTs) were successfully fabricated via a powder metallurgy method. The processing parameters were adopted in such a way to have uniform dispersion of short length CNTs without any damage, as well as re fi ned and dissolved β phases structures throughout the composite matrix. The composite exhibited impressive increase in microhardness(about+23%) and tensile failure strain value(about+98%) without signi fi cant compromise in tensile strength, compared to the un-reinforced Mg–3Al–1Zn alloy. The synthesized composites can be used in automotive and aerospace industries due to their low density and high speci fic strength.

关键词： Metal matrix composites Mechanical properties Powder processing

来源：

同方期刊数据库评论

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Effects of Fe concentration on microstructure and corrosion of Mg-6Al-1Zn-xFe alloys for fracturing balls applications

引用

Journal of Materials Science & technology 2019年第9期35卷 2086-2098页

作者： Cheng Zhang Liang Wu Guangsheng Huang Lin Chen Dabiao Xia Bin Jiang Andrej Atrens Fusheng Pan State Key Laboratory of Mechanical Transmission College of Materials Science and EngineeringChongqing UniversityChongqing 400044China National engineering research center for Magnesium Alloys Chongqing UniversityChongqing 400044China chongqing research center for Advanced Materials Chongqing Academy of Science & TechnologyChongqing 401123China School of Mechanical and Mining engineering The University of QueenslandBrisbane Qld 4072Australia

Mg-6 Al-1 Zn-xFe（x = 0,1,3,5 and 7 wt%）alloys were prepared by powder metallurgy and followed by hot *** of Fe element exists as insoluble particles in the *** as-extruded alloys showed higher degradable rates but less stable mechanical properties than as-annealed *** rate of all the alloys increased with increasing Fe concentration,reaching 2.4 mL cm-2h-1.0.2% yield strength of all the alloys was higher than 150 *** short,Mg-6 Al-1 Zn-xFe alloys have an attractive combination of corrosion and mechanical properties,which holds a bright future for fracturing balls applications.

关键词： Mg-6Al-1Zn-xFe alloys Fracturing balls Corrosion Mechanical properties

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Effects of seasonal variation on soil microbial community structure and enzyme activity in a Masson pine forest in Southwest China

引用

Journal of Mountain Science 2020年第6期17卷 1398-1409页

作者： LUO Song-ping HE Bing-hui ZENG Qing-ping LI Nan-jie YANG Lei College of Resources and Environment Southwest UniversityChongqing 400715China technology Consulting research center of Soil and Water Conservation of Guizhou Province Guiyang 550002China chongqing engineering technology research center for Information Management in Development Chongqing Technology and Business UniversityChongqing 400067China State Key Laboratory of urban and Regional Ecology Research Center for Eco-Environmental SciencesChinese Academy of SciencesBeijing 100085China

Soil microbial communities and enzyme activities play key roles in soil *** are sensitive to changes in environmental factors,including seasonal temperature,precipitation variations and soil *** understand the interactive mechanisms of seasonal changes that affect soil microbial communities and enzyme activities in a subtropical masson pine(Pinus massoniana)forest,we investigated the soil microbial community structure and enzyme activities to identify the effect of seasonal changes on the soil microbial community for two years in Jinyun Mountain National Nature Reserve,chongqing,*** soil microbial community structure was investigated using phospholipid fatty acids(PLFAs).The results indicated that a total of 36 different PLFAs were identified,and 16:0 was found in the highest proportions in the four seasons,moreover,the total PLFAs abundance were highest in spring and lowest in *** and actinomycetes were the dominant types in the study *** changes also had a significant(P<0.05)influence on the soil enzyme *** maximum and minimum values of the invertase and catalase activities were observed in autumn and winter,***,the maximum and minimum values of the urease and phosphatase acid enzymatic activities were found in spring and winter,*** correspondence analysis(CCA)analysis revealed that the seasonal shifts in soil community composition and enzyme activities were relatively more sensitive to soil moisture and temperature,but the microbial community structure and enzyme activity were not correlated with soil pH in the study *** study highlights how the seasonal variations affect the microbial community and function(enzyme activity)to better understand and predict microbial responses to future climate regimes in subtropical area.

关键词： PLFA analysis Soil microorganisms soil enzymes Seasonal shifts Soil moisture Soil temperature

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Defects-rich MgFe LDH:A high-capacity adsorbent for methyl orange wastewater

引用

Chinese Journal of Chemical engineering 2024年第10期74卷 63-73页

作者： Chunmei Zhu Liting Zhang Chenyuan Cui Xin Lian Long Qu Bai He Guoyuan Yuan Jian Feng Siwei Xiang Bo Yu School of Chemistry and Chemical engineering Chongqing University of Science and TechnologyChongqing 401331China research center of Smart Environmental Analysis Chongqing Institute of Green and Intelligent TechnologyChinese Academy of SciencesChongqing 400714China

Dye pollution is a common pollutant in wastewater that poses a serious threat to human *** double hydroxide(LDH)is a commonly used adsorbent for dye ***,its adsorption efficiency is significantly limited by the limited adsorption active sites of the *** this paper,a defects-rich MgFe LDH adsorbent for anionic dye wastewater was synthesized by a simple hydrothermal method and alkaline *** analytical techniques,such as XRD,FT-IR,SEM,TEM,XPS,and N2 adsorption-desorption isotherm,were used to verify the chemical composition and surface characteristics of the materials,and the effects of pH,temperature,and contact time on the adsorption effect of methyl orange and the adsorption mechanism were *** etching of Al and Zn in the laminate generated defects that expose unsaturated coordination centers and create abundant adsorption sites,which can electrostatically attract and coordinate with dye *** 25℃,the adsorption capacity of MgFe LDH with Al etched and MgFe LDH with Zn etched for methyl orange dye reached 1722 mg·g^(-1 ) and 1685 mg·g^(-1 ),respectively,much higher than that of MgFe LDH(544 mg·g^(-1 )).This work provides a promising method for the removal of dye wastewater by adsorption and a new idea for the design and development of high-performance dye wastewater adsorbents.

关键词： MgFe LDH Methyl orange Alkaline etching Defects Adsorption

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Influence of impurities on damping properties of ZK60 magnesium alloy

引用

Transactions of Nonferrous Metals Society of China 2010年第7期20卷 1305-1310页

作者：陈先华毛建军潘复生彭建王敬丰 College of Materials Science and engineering Chongqing University National engineering research center for Magnesium Alloys Chongqing University

The influence of impurities on damping capacities of ZK60 magnesium alloys in the as-cast,as-extruded and T4-treated states was investigated by dynamically mechanical analyzer at room *** and Lucke dislocation pinning model was employed to explain damping properties of the *** is found that reducing impurity content can decrease the amount of second-phase particles,increase grain size and improve damping capacity of the as-cast alloy *** as-extruded alloy with lower impurity content is found to possess obviously higher damping capacity in the relatively high strain region than that with higher impurity concentration,which appears to originate mainly from different dislocation *** variation tendency of damping property with change of impurity content after solution-treatment is also similar to that in the as-extruded and as-cast states. Meanwhile,the purification of the alloy results in an evident improvement in tensile yield strength in the as-extruded state.

关键词： ZK60 magnesium alloy impurities damping dislocation

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Effects of Ce on microstructure of semi-continuously cast Mg-1.5Zn-0.2Zr magnesium alloy ingots

引用

Transactions of Nonferrous Metals Society of China 2010年第B07期20卷 324-330页

作者：赵凯阳彭晓东谢卫东魏群义杨艳魏国兵 College of Materials Science and engineering Chongqing University National engineering research center for Magnesium A lloys Chongqing University

Mg-1.5Zn-0.2Zr-xCe (x=0, 0.1, 0.3, 0.5, mass fraction, %) alloys were prepared by conventional semi-continuous casting. The effect of rare earth Ce on the microstructure of Mg-1.5Zn-0.2Zr-xCe alloys was studied and the distribution of Ce was analyzed by optical microscopy (OM), X-ray diffractometry (XRD) and scanning electron microscopy (SEM). The results indicate that Ce element exists in the form of Mg12Ce phase and has an obvious refining effect on the microstructure of test alloys. As the Ce content increases, the grain size reduces, the grain boundaries turn thinner, and the distribution of Mg12Ce precipitates becomes more and more dispersed. The Mg-1.5Zn-0.2Zr alloy with 0.3%Ce has the best refinement effect. From center to periphery of the ingot, the amount of granular precipitates in the grain reduces. In longitudinal section of the ingot, some relative long columnar grains appear.

关键词： Mg-1.5Zn-0.2Zr alloy Ce semi-continuous casting refinement

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Enhancing hydrogen storage performance via optimizing Y and Ni element in magnesium alloy

引用

Journal of Magnesium and Alloys 2022年第3期10卷 888-903页

作者： Xu Pang Lei Ran Yu'an Chen Yuxiao Luo Fusheng Pan College of materials Science and engineering Chongqing UniversityChongqing 400044China National engineering research for magnesium Alloys Chongqing UniversityChongqing 400044China Guangdong Guoyan Science and technology research center Co. LtdGuangdong 518000China

Magnesium-based hydrogen storage materials are considered as one of the most promising candidates for solid state hydrogen storage due to their advantages of high hydrogen capacity,excellent reversibility and low *** this paper,Mg_(91.4)Ni_(7)Y_(1.6) and Mg_(92.8)Ni_(2.4)Y_(4.8) alloys were prepared by melting and ball *** microstructures and phases were characterized by X-ray diffraction,scanning electron microscope and transmission electron microscope,and hydrogen absorbing and desorbing properties were tested by the high pressure gas adsorption apparatus and differential scanning calorimetry(DSC).In order to estimate the activation energy and growth mechanism of alloy hydride,the JMAK,Arrhenius and Kissinger methods were applied for *** hydrogen absorption content of Mg_(92.8)Ni_(2.4)Y_(4.8) alloy reaches 3.84 wt.%within 5 min under 350℃,3 MPa,and the maximum hydrogen capacity of the alloy is 4.89 wt.%in same ***,the hydrogen absorption of Mg_(91.4)Ni_(7)Y_(1.6) alloy reaches 5.78 wt.%within 5 min,and the maximum hydrogen absorption of the alloy is 6.44 wt.%at 350℃and 3 *** hydrogenation activation energy of Mg_(94.4)Ni_(7)Y_(1.6) alloy is 25.4 kJ/mol H_(2),and the enthalpy and entropy of hydrogen absorption are-60.6 kJ/mol H_(2) and 105.5 J/K/mol H_(2),*** alloy begins to dehydrogenate at 210℃,with the dehydrogenation activation energy of 87.7 kJ/mol H_(2).By altering the addition amount of Ni and Y elements,the 14 H-LPSO phase with smaller size and ternary eutectic areas with high volume fraction are obtained,which provides more phase boundaries and catalysts with better dispersion,and there are a lot of fine particles in the alloy,these structures are beneficial to enhance the hydrogen storage performance of the alloys.

关键词： Hydrogen storage materials LPSO phase Catalytic effect Hydrogen storage performance

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

欢迎您,

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案：

请选择收藏分类：

通借通还

欢迎您,

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：