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Electrolyte Design for Low‑Temperature Li‑Metal Batteries:Challenges and Prospects 被引量:1
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作者 Siyu Sun Kehan Wang +3 位作者 Zhanglian Hong Mingjia Zhi Kai Zhang Jijian Xu 《Nano-Micro Letters》 SCIE EI CAS CSCD 2024年第2期365-382,共18页
Electrolyte design holds the greatest opportunity for the development of batteries that are capable of sub-zero temperature operation.To get the most energy storage out of the battery at low temperatures,improvements ... Electrolyte design holds the greatest opportunity for the development of batteries that are capable of sub-zero temperature operation.To get the most energy storage out of the battery at low temperatures,improvements in electrolyte chemistry need to be coupled with optimized electrode materials and tailored electrolyte/electrode interphases.Herein,this review critically outlines electrolytes’limiting factors,including reduced ionic conductivity,large de-solvation energy,sluggish charge transfer,and slow Li-ion transportation across the electrolyte/electrode interphases,which affect the low-temperature performance of Li-metal batteries.Detailed theoretical derivations that explain the explicit influence of temperature on battery performance are presented to deepen understanding.Emerging improvement strategies from the aspects of electrolyte design and electrolyte/electrode interphase engineering are summarized and rigorously compared.Perspectives on future research are proposed to guide the ongoing exploration for better low-temperature Li-metal batteries. 展开更多
关键词 Solid electrolyte interphase Li metal low temperature Electrolyte design BATTERIES
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High Efficient Technology of Steelmaking With Low Silicon Hot Metal on Large Converter 被引量:2
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作者 JIANG Xiao-fang WANG Ming-lin +3 位作者 YANG Wen-yuan GAN Yong WANG Ying-jun YU Zu-da 《Journal of Iron and Steel Research International》 SCIE EI CAS CSCD 2007年第6期27-31,52,共6页
To resolve the difficulty in slag formation during steelmaking with low silicon hot metal and to increase productivity, a new 5-hole lance was developed by increasing oxygen flow from 50 000 m^3/h to 60 000 m^3/h. Syn... To resolve the difficulty in slag formation during steelmaking with low silicon hot metal and to increase productivity, a new 5-hole lance was developed by increasing oxygen flow from 50 000 m^3/h to 60 000 m^3/h. Synthetic slag was added to adjust the slag composition. The problems such as difficulty in dephosphorization and slag adhesion to oxygen lance and hood were settled. Steel production and metal yield were increased and the nozzle life was prolonged through these techniques. 展开更多
关键词 CONVERTER hot metal low silicon content synthetic slag NOZZLE
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Effect of normalizing cooling process on microstructure and precipitates in low-temperature silicon steel 被引量:7
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作者 李慧 冯运莉 +2 位作者 宋孟 梁精龙 苍大强 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2014年第3期770-776,共7页
Microstructure, precipitate and magnetic characteristic of fmal products with different normalizing cooling processes for Fe-3.2%Si low-temperature hot-rolled grain-oriented silicon steel were analyzed and compared wi... Microstructure, precipitate and magnetic characteristic of fmal products with different normalizing cooling processes for Fe-3.2%Si low-temperature hot-rolled grain-oriented silicon steel were analyzed and compared with the hot-rolled plate by optical microscopy (OM), transmission electron microscopy (TEM), and energy dispersive spectrometry (EDS). The results show that, the surface microstructure is uniform, the proportion of recrystallization in matrix increases, and the banding textures are narrowed; the precipitates, whose quantity in normalized plate is more than that in hot-rolled plate greatly, are mainly A1N, MnS, composite precipitates (Cu,Mn)S and so on. Normalizing technology with a temperature of 1120 ℃, holding for 3 min, and a two-stage cooling is a most advantaged method to obtain oriented silicon steel with sharper Goss texture and higher magnetic properties, owing to the uniform surface microstructures and the obvious inhomogeneity of microstructures along the thickness. The normalizing technology with the two-stage cooling is the optimum process, which can generate more fine precipitates dispersed over the matrix, and be beneficial for finished products to get higher magnetic properties. 展开更多
关键词 low temperature grain-oriented silicon steel normalizing cooling process MICROSTRUCTURE PRECIPITATE magnetic property
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Investigation on Steelmaking with Hot Metal Containing Low Silicon Content in Large Converter
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作者 WANG Ming-lin WU Wen-dong +3 位作者 YANG Wen-yuan SHI Hong-zhi WANG Tao ZHANG Geng 《Journal of Iron and Steel Research International》 SCIE CAS CSCD 2005年第5期6-10,共5页
There are some problems in steelmaking with hot metal containing low silicon content such as difficulty in slag formation, less slag for dephosphorization and slag adhesion on oxygen lance and hood. To overcome these ... There are some problems in steelmaking with hot metal containing low silicon content such as difficulty in slag formation, less slag for dephosphorization and slag adhesion on oxygen lance and hood. To overcome these problems, experiments wcrc conducted and some improvements were obtained, such as adding appropriate flux, increasing the lance position slightly during steelmaking and using effective multi-outlet nozzle. Moreover, to keep normal heating rate, the ore and scrap charge should be reduced due to less chemical heat input in steelmaking. 展开更多
关键词 hot metal low silicon content slag formation DEPHOSPHORIZATION chemical heat
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Recent progress in CO oxidation over Pt-group-metal catalysts at low temperatures 被引量:10
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作者 林坚 王晓东 张涛 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 北大核心 2016年第11期1805-1813,共9页
CO oxidation is probably the most studied reaction in heterogeneous catalysis.This reaction has become a hot topic with the discovery of nanogold catalysts,which are active at low temperatures(at or below room temper... CO oxidation is probably the most studied reaction in heterogeneous catalysis.This reaction has become a hot topic with the discovery of nanogold catalysts,which are active at low temperatures(at or below room temperature).Au catalysts are the benchmark for judging the activities of other metals in CO oxidation.Pt-group metals(PGMs) that give comparable performances are of particular interest.In this mini-review,we summarize the advances in various PGM(Pt,Pd,Ir,Rh,Ru)catalysts that have high catalytic activities in low-temperature CO oxidation arising from reducible supports or the presence of OH species.The effects of the size of the metal species and the importance of the interface between the metal and the reducible support are covered and discussed in terms of their promotional role in CO oxidation at low temperatures. 展开更多
关键词 Carbon monoxide oxidation GOLD Platinum group metal low temperature Size effect INTERFACE
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Low temperature solid-phase sintering of sintered metal fibrous media with high specific surface area 被引量:4
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作者 唐彪 汤勇 +3 位作者 周蕤 陆龙生 刘彬 屈修明 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2011年第8期1755-1760,共6页
A procedure of low temperature solid-phase sintering(LTSS) was carried out to fabricate sintered metal fibrous media(SMFM) with high specific surface area.Stainless steel fibers which were produced by cutting proc... A procedure of low temperature solid-phase sintering(LTSS) was carried out to fabricate sintered metal fibrous media(SMFM) with high specific surface area.Stainless steel fibers which were produced by cutting process were first plated with a coarse copper coating layer by electroless plating process.A low-temperature sintering process was then completed at about 800 °C for 1 h under the protection of hydrogen atmosphere.The results show that a novel SMFM with complex surface morphology and high specific surface area(0.2 m2/g) can be obtained in this way.The effect of sintering temperature on the surface morphology and specific surface area of SMFM was studied by means of scanning electron microscopy and Brunauer-Emmett-Teller.The damage of micro-structure during the sintering process mainly contributed to the loss of specific surface area of SMFM and the optimal sintering temperature was 800 °C. 展开更多
关键词 sintered metal fibrous media low temperature solid-phase sintering electroless copper plating surface morphology specific surface area
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Cell-nucleus structured electrolyte for low-temperature aqueous zinc batteries 被引量:3
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作者 Yang Dong Ning Zhang +4 位作者 Zhaodong Wang Jinhan Li Youxuan Ni Honglu Hu Fangyi Cheng 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2023年第8期324-332,I0010,共10页
Rechargeable aqueous zinc(Zn) batteries hold great promise for large-scale energy storage,but their implementation is plagued by poor Zn reversibility and unsatisfactory low-temperature performance.Herein,we design a ... Rechargeable aqueous zinc(Zn) batteries hold great promise for large-scale energy storage,but their implementation is plagued by poor Zn reversibility and unsatisfactory low-temperature performance.Herein,we design a cell-nucleus structured electrolyte by introducing low-polarity 1,2-dimethoxyethane(DME) into dilute 1 M zinc trifluoromethanesulfonate(Zn(OTf)_(2)) aqueous solution,which features an OTf--rich Zn2^(+)-primary solvation sheath(PSS,inner nucleus) and the DMEmodulated Zn^(2+)-outer solvation sheath(outer layer).We find that DME additives with a low dosage do not participate in the Zn2+-PSS but reinforce the Zn-OTf-coordination,which guarantees good reaction kinetics under ultralow temperatures.Moreover,DME breaks the original H-bonding network of H2O,depressing the freezing point of electrolyte to-52.4℃.Such a cell-nucleus-solvation structure suppresses the H_(2)O-induced side reactions and forms an anion-derived solid electrolyte interphase on Zn and can be readily extended to 1,2-diethoxyethane.The as-designed electrolyte enables the Zn electrode deep cycling stability over 3500 h with a high depth-of-discharge of 51.3% and endows the Zn‖V_(2)O_(5)full battery with stable cycling over 1000 cycles at 40℃.This work would inspire the solvation structure design for low-temperature aqueous batteries. 展开更多
关键词 Aqueous zinc batteries low temperature Cell-nucleus solvation structure Zn metal anode Solid electrolyte interphase
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Oxidation of CO on Nanometer Metal Oxides at Low Temperatures 被引量:3
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作者 ZHANG Wen-xiang JIA Ming-jun +4 位作者 ZHAO Ing-zhe ZHANG Chun-lei WU Tong-hao WANG Xue-guang SUN Tie 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 1997年第4期75-77,共3页
OxidationofCOonNanometerMetalOxidesatLowTemperatures*ZHANGWen-xiang**,JIAMing-jun,ZHAOJing-zhe,ZHANGChun-lei... OxidationofCOonNanometerMetalOxidesatLowTemperatures*ZHANGWen-xiang**,JIAMing-jun,ZHAOJing-zhe,ZHANGChun-lei,WUTong-hao(Depar... 展开更多
关键词 Oxidation of carbon monooxide Nanometer metal oxide low temperature
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Open-circuit voltage analysis of p-i-n type amorphous silicon solar cells deposited at low temperature 被引量:1
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作者 Ni Jian Zhang Jian-Jun Cao Yu Wang Xian-Bao Li Chao Chen Xin-Liang Geng Xin-Hua Zhao Ying 《Chinese Physics B》 SCIE EI CAS CSCD 2011年第8期403-407,共5页
This paper identifies the contributions of p-a-SiC:H layers and i-a-Si:H layers to the open circuit voltage of p-i-n type a-Si:H solar cells deposited at a low temperature of 125℃. We find that poor quality p-a-Si... This paper identifies the contributions of p-a-SiC:H layers and i-a-Si:H layers to the open circuit voltage of p-i-n type a-Si:H solar cells deposited at a low temperature of 125℃. We find that poor quality p-a-SiC:H films under regular conditions lead to a restriction of open circuit voltage although the band gap of the i-layer varies widely. A significant improvement in open circuit voltage has been obtained by using high quality p-~SiC:H films optimized at the "low-power regime" under low silane flow rates and high hydrogen dilution conditions. 展开更多
关键词 amorphous silicon solar cell low temperature open-circuit voltage
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Optimization of low-temperature alkaline smelting process of crushed metal enrichment originated from waste printed circuit boards 被引量:5
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作者 郭学益 刘静欣 《Journal of Central South University》 SCIE EI CAS CSCD 2015年第5期1643-1650,共8页
A novel low-temperature alkaline smelting process is proposed to convert and separate amphoteric metals in crushed metal enrichment originated from waste printed circuit boards. The central composite design was used t... A novel low-temperature alkaline smelting process is proposed to convert and separate amphoteric metals in crushed metal enrichment originated from waste printed circuit boards. The central composite design was used to optimize the operating parameters,in which mass ratio of Na OH-to-CME, smelting temperature and smelting time were chosen as the variables, and the conversions of amphoteric metals tin, lead, aluminum and zinc were response parameters. Second-order polynomial models of high significance and3 D response surface plots were constructed to show the relationship between the responses and the variables. Optimum area of80%-85% Pb conversion and over 95% Sn conversion was obtained by the overlaid contours at mass ratio of Na OH-to-CME of4.5-5.0, smelting temperature of 653-723 K, smelting time of 90-120 min. The models were validated experimentally in the optimum area, and the results demonstrate that these models are reliable and accurate in predicting the smelting process. 展开更多
关键词 low-temperature alkaline smelting waste printed circuit board amphoteric metals central composite design conversion
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Silicon Film Fabrication by Liquid Phase Epitaxy at Low Temperature 被引量:1
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作者 QIANYongbiao SHIWeimin 《Semiconductor Photonics and Technology》 CAS 1998年第1期18-24,共7页
Low temperature liquid phase epitaxy of silicon thin films was successfully carried out at a temperature of (400~500)℃,using Au/Bi alloy as a Si-saturated Sn solution was used to protect the substrate surface,preven... Low temperature liquid phase epitaxy of silicon thin films was successfully carried out at a temperature of (400~500)℃,using Au/Bi alloy as a Si-saturated Sn solution was used to protect the substrate surface,preventing effectively the oxidation of silicon.The grown Si thin films were identified by SEM,AES and C-V measurements. 展开更多
关键词 low temperature LPE silicon Film Solar Cell
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TiO_2-Supported Binary Metal Oxide Catalysts for Low-temperature Selective Catalytic Reduction of NO_x with NH_3 被引量:5
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作者 WU Bi-jun LIU Xiao-qin +1 位作者 XIAO Ping WANG Shu-gang 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 2008年第5期615-619,共5页
Binary metal oxide(MnOx-A/TiO2)catalysts were prepared by adding the second metal to manganese oxides supported on titanium dioxide(TiO2),where,A indicates Fe2O3,WO3,MoO3,and Cr2O3.Their catalytic activity,N2 sele... Binary metal oxide(MnOx-A/TiO2)catalysts were prepared by adding the second metal to manganese oxides supported on titanium dioxide(TiO2),where,A indicates Fe2O3,WO3,MoO3,and Cr2O3.Their catalytic activity,N2 selectivity,and SO2 poisonous tolerance were investigated.The catalytic performance at low temperatures decreased in the following order:Mn-W/TiO2〉Mn-Fe/TiO2〉Mn-Cr/TiO2〉Mn-Mo/TiO2,whereas the N2 selectivity decreased in the order:Mn-Fe/TiO2〉Mn-W/TiO2〉Mn-Mo/TiO2〉Mn-Cr/TiO2.In the presence of 0.01%SO2 and 6%H2O,the NOx conversions in the presence of Mn-W/TiO2,Mn-Fe/TiO2,or Mn-Mo/TiO2 maintain 98.5%,95.8%and 94.2%, respectively,after 8 h at 120°C at GHSV 12600 h? 1 .As effective promoters,WO3 and Fe2O3 can increase N2 selectivity and the resistance to SO2 of MnOx/TiO2 significantly.The Fourier transform infrared(FTIR)spectra of NH3 over WO3 show the presence of Lewis acid sites.The results suggest that WO3 is the best promoter of MnOx/TiO2,and Mn-W/TiO2 is one of the most active catalysts for the low temperature selective catalytic reduction of NO with NH3. 展开更多
关键词 Selective catalytic reduction of NO with NH3 low-temperature selective catalytic reduction Binary metal oxide catalyst FTIR NH3-TPD
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Low-temperature alteration of oceanic island basalts and their contribution to transition metal circulation of the ocean 被引量:1
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作者 BU Wenrui SHI Xuefa +3 位作者 PENG Jiantang LIU Jihua Zhang Mingjie QI Liang 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2008年第2期35-54,共20页
The major elements, rare earth elements (REE) and trace elements of four basalt samples from central and western Pacific ferro- manganese crust provinces have been analyzed using chemical methods and ICP - MS, respe... The major elements, rare earth elements (REE) and trace elements of four basalt samples from central and western Pacific ferro- manganese crust provinces have been analyzed using chemical methods and ICP - MS, respectively. The results indicate that the samples have been extensively altered and that the contents of their major elements have changed significantly. However, the similarity of REE partition patterns and trace element contents of basalt samples to those of fresh oceanic island basalts (OIB) indicate that the basalt samples originated as OIB. Because of low-temperature alteration, the contents of A1203 , Fe203 , MnO, K20 and P205 increased, while MgO and FeO decreased. Active components, such as magnesium and iron, were leached from OIB resulting in the relative enrichment of SiO2. The leaching of active components can cause the relative enrichment of REE, while the precipitation of LREE-rich ferromanganese oxides in vesicles and fissures not only causes an increase of REE contents, but also induces "fractionation" of LREE and HREE. Based on the enrichment mechanism of REE contents, the theoretical quantities of precipitated ferromanganese oxides and the depleted quantities of active components are calculated : the depleted quantities of active components for the unit mass of fresh basalts vary in the range of 0.15 ~ 0. 657, and the precipitated quantities of ferromanganese oxides for the unit mass of fresh basahs vary in the range of 0. 006 ~ 0. 042. Of the major elements, the two most depleted are iron, and magnesium, with 18.28% ~ 70.95% of iron and 44.50% ~ 93.94% of magnesium in the fresh basalts was leached out. Theoretical calculation and geochemistry results both indicate that low-temperature alteration of basalts can supply abundant amount of metals to seawater, and may play an important role in ocean metal circulation. 展开更多
关键词 oceanic island basahs OIB) low-temperature alteration ocean metal circulation theoretical calculation cobaltrich ferromanganese crusts
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Evaluation of a gate-first process for AlGaN/GaN metal-oxide-semiconductor heterostructure field-effect transistors with low ohmic annealing temperature 被引量:1
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作者 李柳暗 张家琦 +1 位作者 刘扬 敖金平 《Chinese Physics B》 SCIE EI CAS CSCD 2016年第3期445-447,共3页
In this paper, TiN/A1Ox gated A1GaN/GaN metal-oxide-semiconductor heterostructure field-effect transistors (MOS- HFETs) were fabricated for gate-first process evaluation. By employing a low temperature ohmic process... In this paper, TiN/A1Ox gated A1GaN/GaN metal-oxide-semiconductor heterostructure field-effect transistors (MOS- HFETs) were fabricated for gate-first process evaluation. By employing a low temperature ohmic process, ohmic contact can be obtained by annealing at 600 ℃ with the contact resistance approximately 1.6 Ω.mm. The ohmic annealing process also acts as a post-deposition annealing on the oxide film, resulting in good device performance. Those results demonstrated that the TiN/A1Ox gated MOS-HFETs with low temperature ohmic process can be applied for self-aligned gate AIGaN/GaN MOS-HFETs. 展开更多
关键词 metal-oxide-semiconductor heterostructure field-effect transistors low temperature ohmic pro-cess inductively coupled plasma
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A PROBABILISTIC ASSESSMENT OF TEMPERATURE EFFECTSON THE LOW CYCLE FATIGUE BEHAVIOUR OF 1Cr_(18)Ni_9Ti STEEL WELD METAL
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作者 Q.Gao Y.X.Zhao L.X.Cai 《Acta Metallurgica Sinica(English Letters)》 SCIE EI CAS CSCD 1998年第6期477-484,共8页
Based on the test results obtained from the single-step test and the incremental-step test at room temperature and 240℃, a probabilistic assessment of temperature effects on the cyclic stress-strum response and the f... Based on the test results obtained from the single-step test and the incremental-step test at room temperature and 240℃, a probabilistic assessment of temperature effects on the cyclic stress-strum response and the fatigue life of 1Cr18Ni9Ti steel weld metal is performed. In orber to assess the temperature effect on cyclic stress amplitude where there is a scatter of the material cyclic constitution, a probabilistic assessment approach on the basis of probabilistic modified Ramberg-Osgood relations is introduced.The investigation shows that the cyclic stress amplitude and the scatter of cyclic stress amplitude data are decreased at 240℃. Similarly, from the consideration of the fatigue life scatter a probabilistic assessment of temperature effect on the fatigue life is suggested on the basis of probabilistic Langer S-N relations. The investigation shows that the crack initiation life is increased and the scatter of crack initiation life data is decreased at 240℃. 展开更多
关键词 1Cr_(18)Ni_9Ti stainless steel weld metal low cycle fatigue temperature effect probabilistic assessment
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Pressure-Induced Metallization and Electrical Phase Diagram for Polycrystalline CaB_6 under High Pressure and Low Temperature
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作者 杨洁 焦阳 +1 位作者 韩永昊 李晶 《Chinese Physics Letters》 SCIE CAS CSCD 2016年第8期88-90,共3页
The electrical properties of polycrystaltine CaB6 are revealed by in-situ resistance measurements under high pressure and low temperature. Due to the existence of grain boundaries, polycrystalline CaB6 behaves with se... The electrical properties of polycrystaltine CaB6 are revealed by in-situ resistance measurements under high pressure and low temperature. Due to the existence of grain boundaries, polycrystalline CaB6 behaves with semiconducting transport properties, which is different from the semimetallic CaB6 single crystals. The temperaturedependent resistance measurement results show that before the structural phase transition at 12.3 GPa the high pressure first induces the metallization at 6.5 GPa for CAB6. Moreover, the phase diagram for CaB6 is drawn based on the investigated electric conducting properties and at least three different conducting phases are found even at moderate high pressure and low temperature, indicating that the electric nature of CaB6 is very sensitive to the environment. 展开更多
关键词 for is of Pressure-Induced metallization and Electrical Phase Diagram for Polycrystalline CaB6 under High Pressure and low temperature in high been that
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Effects of Low Temperature Plasma on the Forms of Heavy Metals in Sludge
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作者 Xu Fuyin Hu Yanyan +2 位作者 Chen Xiang Bao Bing Wang Kaiyang 《Meteorological and Environmental Research》 CAS 2019年第1期52-54,58,共4页
Low temperature plasma was used to treat sludge,and the effects of discharge time on the content of different forms of heavy metals in the sludge were studied. The results showed that Cu and Zn content in the domestic... Low temperature plasma was used to treat sludge,and the effects of discharge time on the content of different forms of heavy metals in the sludge were studied. The results showed that Cu and Zn content in the domestic sludge could basically meet the requirements of GB 4284-2018,GB/T 23486-2009,CJ/T 362-2011 and CJ/T 309-2009. There were big differences between different forms of the heavy metals. According to the proportions of different forms of Cu in the sludge,different forms of Cu are arranged as follows: organic state > carbonate bound state> residual state > exchangeable state > iron-manganese oxidation state,and Cu mainly existed in an organic state. Various forms of Zn are arranged in order of the proportion as follows: iron-manganese oxidation state > residual state > carbonate bound state > exchangeable state > organic state,and Zn mainly existed in an iron-manganese oxidation state. After the treatment of sludge by low temperature plasma,the content of exchangeable Cu and Zn in the sludge increased,while the content and proportion of residual Cu and Zn all reduced. 展开更多
关键词 low temperature plasma SLUDGE Heavy metals Exchangeable state Carbonate bound state Iron-manganese oxidation state Organic state Residual state
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Low Temperature Growth of Hydrogenated Silicon Prepared by PECVD from Argon Diluted Silane Plasma
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作者 Rachid Amrani Pascale Abboud +1 位作者 Larbi Chahed Yvan Cuminal 《Crystal Structure Theory and Applications》 2012年第3期62-67,共6页
In order to contribute to the understanding of the optoelectronics properties of hydrogenated nanocrystalline silicon thin films, a detailed study has been conducted. The samples were deposited by 13.56 MHz PECVD (Pla... In order to contribute to the understanding of the optoelectronics properties of hydrogenated nanocrystalline silicon thin films, a detailed study has been conducted. The samples were deposited by 13.56 MHz PECVD (Plasma-Enhanced Chemical Vapor Deposition) of silane argon mixture. The argon dilution of silane for all samples studied was 96% by volume. The substrate temperature was fixed at 200oC. The influence of depositions parameters on optical proprieties of samples was studied by UV-Vis-NIR spectroscopy. The structural evolution was studied by Raman spectroscopy and X-ray diffraction (XRD). Intrinsic-layer samples depositions were made in this experiment in order to obtain the transition from the amorphous to crystalline phase materials. The deposition pressure varied from 400 mTorr to 1400 mTorr and the rf power from 50 to 250 W. The structural evolution studies show that beyond 200 W, we observed an amorphous-nanocrystalline transition, with an increase in crystalline fraction by increasing rf power and working pressure. Films near the amorphous to nanocrystalline transition region are grown at reasonably high deposition rates (~10 /s), which are highly desirable for the fabrication of cost effective devices. The deposition rate increases with increasing rf power and process pressure. Different crystalline fractions (21% to 95%) and crystallite size (6 - 16 nm) can be achieved by controlling the process pressure and rf power. These structural changes are well correlated to the variation of optical proprieties of the thin films. 展开更多
关键词 silicon PECVD DEPOSITION Rate AMORPHOUS NANOCRYSTALLINE Transition ARGON low temperature
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Synthesis of Pd nanoparticles supported on CeO_2 nanotubes for CO oxidation at low temperatures 被引量:5
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作者 吴静谧 曾亮 +3 位作者 程党国 陈丰秋 詹晓力 巩金龙 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 北大核心 2016年第1期83-90,共8页
Developing efficient supported Pd catalysts and understanding their catalytic mechanism in CO oxidation are challenging research topics in recent years.This paper describes the synthesis of Pd nanoparticles supported ... Developing efficient supported Pd catalysts and understanding their catalytic mechanism in CO oxidation are challenging research topics in recent years.This paper describes the synthesis of Pd nanoparticles supported on CeO2 nanotubes via an alcohol reduction method.The effect of the support morphology on the catalytic reaction was explored.Subsequently,the performance of the prepared catalysts was investigated toward CO oxidation reaction and characterized by Nitrogen sorption,X-ray diffraction,X-ray photoelectron spectroscopy,transmission electron microscopy,and CO-temperature-programmed desorption techniques.The results indicated that the catalyst of Pd on CeO2 nanotubes exhibits excellent activity in CO oxidation at low temperatures,due to its large surface area,the high dispersion of Pd species,the mesoporous and tubular structure of the CeO2-nanotube support,the abundant Ce3+,formation of Pd–O–Ce bonding,and enhanced metal–support interaction on the catalyst surface. 展开更多
关键词 Cerium oxide nanotube Palladium nanoparticle metal–support interaction Carbon monoxide oxidation low temperature
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A Review on Complete Oxidation of Methane at Low Temperatures 被引量:2
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作者 ZhenhuaLi GarB.Hoflund 《Journal of Natural Gas Chemistry》 EI CAS CSCD 2003年第3期153-160,共8页
This paper reviews recent developments in complete oxidation of methane atlow temperatures over noble metal catalysts in the past 20 years. The Pd/Al_2O_3 catalyst system isfully discussed. The review mainly focuses o... This paper reviews recent developments in complete oxidation of methane atlow temperatures over noble metal catalysts in the past 20 years. The Pd/Al_2O_3 catalyst system isfully discussed. The review mainly focuses on the kinetic aspects of methane oxidation over thiscatalyst, and methane activation behavior over Pd and PdO phases (the form of PdO on the surface,transient behavior, the nature of the active sites, the influence of metal particle size and theirstructure sensitivities, and so on). Some Pd catalysts supported on other oxides besides the Al_2O_3support are briefly discussed. Possible routes of non-noble metal catalysts as substitutes for thePd catalyst are also proposed. 展开更多
关键词 METHANE complete oxidation REVIEW PD low temperature noble metal
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