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Loosely coordinating diluted highly concentrated electrolyte toward -60℃ Li metal batteries
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作者 Han Zhang Ziqi Zeng +5 位作者 Qiang Wu Xinlan Wang Mingsheng Qin Sheng Lei Shijie Cheng Jia Xie 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第3期380-387,I0009,共9页
Lithium metal batteries(LMBs) promise energy density over 400 Wh kg^(-1).However,they suffer severe electrochemical performance deterioration at sub-zero temperatures.Such failure behavior highly correlates to inferio... Lithium metal batteries(LMBs) promise energy density over 400 Wh kg^(-1).However,they suffer severe electrochemical performance deterioration at sub-zero temperatures.Such failure behavior highly correlates to inferior lithium metal anode(LMA) compatibility and sluggish Li^(+) desolvation.Here,we demonstrate that cyclopentylmethyl ether(CPME) based diluted high-concentration electrolyte(DHCE)enables-60℃ LMBs operation.By leveraging the loose coordination between Li^(+) and CPME,such developed electrolyte boosts the formation of ion clusters to derive anion-dominant interfacial chemistry for enhancing LMA compatibility and greatly accelerates Li^(+) desolvation kinetics.The resulting electrolyte demonstrates high Coulombic efficiencies(CE),providing over 99.5%,99.1%,98.5% and 95% at 25,-20,-40,and-60℃respectively.The assembled Li-S battery exhibits remarkable cyclic stability in-20,and-40℃ at 0.2 C charging and 0.5 C discharging.Even at-60℃,Li-S cell with this designed electrolyte retains> 70% of the initial capacity over 170 cycles.Besides,lithium metal coin cell and pouch cell with10 mg cm^(-2) high S cathode loading exhibit cycling stability at-20℃.This work offers an opportunity for rational designing electrolytes toward low temperature LMBs. 展开更多
关键词 Lithium metal batteries -60℃operation Lithium metal anode compatibility Li^(+) desolvation kinetics
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Theoretical Study on the Structures and Magnetic Properties of Metal String Complexes Containing Rigid Equatorial Ligands [Ni3(L)4(NCS)2] (L = dzp-, mpmpa-, mppda-, mptpa-)
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作者 班颖 陈蓉 +2 位作者 李波 许旋 徐志广 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2017年第7期1077-1085,共9页
Density functional theory at the BP86 level was used to investigate the influence of equatorial ligands on the Ni–Ni interactions and magnetic coupling properties of metal string complexes [Ni3(L)4(NCS)2] (L rep... Density functional theory at the BP86 level was used to investigate the influence of equatorial ligands on the Ni–Ni interactions and magnetic coupling properties of metal string complexes [Ni3(L)4(NCS)2] (L represents the rigid equatorial ligands; L = dzp- (1), mpmpa- (2), mppda- (3), mptpa- (4)). The following conclusions can be drawn. (1) With increasing the radius of the connecting atom in the cental ring in equatorial ligands, the two pyridine rings bend down, resulting in the decreasing distance between the two pyridine-nitrogen atoms and the Ni–Ni distance. Therefore, the strength order of the Ni–Ni interaction is 4 〉 2 〉 3 〉 1. The Ni–Ni interactions in 2 and 4 are stronger than those in Ni3(dpa)4(NCS)2 containing no-rigid equatorial ligands. (2) The calculated -Jab is 4 〉 2 〉 3 〉 1. There are two types of magnetic exchange pathways in these complexes: the σ-type pathway through the Ni36+ chains and the δ-type pathway through the equatorial ligands. The magnetic coupling through the metals is the dominant part. Hence, the magnetic coupling strength increases with increasing the Ni–Ni interaction. Modifying the radius of the connecting atom may be one of the means to fine tuning of magnetic coupling strength of this kind of metal string complexes. 展开更多
关键词 metal string complex rigid equatorial ligands density functional theory magnetic coupling constant
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Dual-function protective layer for highly reversible Zn anode
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作者 Jiaming Li Hanhao Liang +6 位作者 Yini Long Xiao Yu Jiaqi Li Nan Li Junyi Han Jianglin Wang Zhanhong Yang 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第11期12-23,共12页
The thermodynamic instability of zinc anodes in aqueous electrolytes leads to issues such as corrosion,hydrogen evolution reactions(HER), and dendrite growth, severely hindering the practical application of zinc-based... The thermodynamic instability of zinc anodes in aqueous electrolytes leads to issues such as corrosion,hydrogen evolution reactions(HER), and dendrite growth, severely hindering the practical application of zinc-based aqueous energy storage devices. To address these challenges, this work proposes a dualfunction zinc anode protective layer, composed of Zn-Al-In layered double oxides(ILDO) by rationally designing Zn-Al layered double hydroxides(Zn-Al LDHs) for the first time. Differing from previous works on the LDHs coatings, firstly, the ILDO layer accelerates zinc-ion desolvation and also captures and anchors SO_(4)^(2-). Secondly, the in-situ formation of the Zn-In alloy phase effectively lowers the nucleation energy barrier, thereby regulating zinc nucleation. Consequently, the zinc anode with the ILDO protective layer demonstrates long-term stability exceeding 1900 h and low voltage hysteresis of 7.5 m V at 0.5 m A cm^(-2) and 0.5 m A h cm^(-2). Additionally, it significantly enhances the rate capability and cycling performance of Zn@ILDO//MnO_(2) full batteries and Zn@ILDO//activated carbon zinc-ion hybrid capacitors.This simple and effective dual-function protective layer strategy offers a promising approach for achieving high-performance zinc-ion batteries. 展开更多
关键词 Protection layer Zn-Al-In layered double oxide Captures and anchors SO_(4)^(2-) Zn-In alloy phase Zn metal anode
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The Evolutionary History of Ore-forming Processes of Metallic Ore Deposits in Northern Guangxi
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作者 Chen Yuchuan, Mao Jinwen and Wang Ping’an Chinese Academy of Geological Sciences, Beijing Fei Zhenbi 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 1995年第2期155-170,共16页
The northern Guangxi region is an important rare metal, rare earth metal and polymetallic metallogenic province. In the region there exist five metallogenic series and two metallogenic subseries, whose metallogenesis ... The northern Guangxi region is an important rare metal, rare earth metal and polymetallic metallogenic province. In the region there exist five metallogenic series and two metallogenic subseries, whose metallogenesis shows features of polycyclic spiral evolution throughout the geological history. As far as various cycles are concerned, mantle-derived ore substances were reduced while crust-derived ore substances increased from early to late timesfin the whole geological evolutionary history, mantle-derived substances decreased gradually while crust-derived ones increased. Meanwhile ore element associations became more and more varied. In terms of space, mineralization migrated from the old basement outwards, i.e. from west to east during the Precambrian, and from north to south during the Phanerozoic, and again from east to west during the Yanshanian. 展开更多
关键词 metallogenic series evolutionary history of ore - forming processes metallogenic model rare metal- nonferrous metal deposit
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Doping dependent metal to insulator transition in the(Bi,Pb)-2212 system:The evolution of structural and electronic properties with europium substitution
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作者 Shabna Razia Sarun Pallian Murikoli +1 位作者 Vinu Surendran Syamaprasad Upendran 《Chinese Physics B》 SCIE EI CAS CSCD 2009年第9期4000-4006,共7页
The present work investigates the effect of europium substitution on the (Bi, Pb)-2212 system in the concentration range 0.5 ≤ x ≤1.0. Phase analysis and lattice parameter calculations on the powder diffraction da... The present work investigates the effect of europium substitution on the (Bi, Pb)-2212 system in the concentration range 0.5 ≤ x ≤1.0. Phase analysis and lattice parameter calculations on the powder diffraction data and the elemental analysis of EDX show that the Eu atoms are successfully substituted into the (Bi, Pb)-2212 system. Resistivity measurements (64-300 K) reveal that the system exhibits superconductivity at x ≤ 0.5 and semiconductivity at x 〉 0.5. With the complete suppression of superconductivity which is known to be a quasi-two dimensional phenomenon in these materials, a metal to insulator transition takes place at x = 0.6 and the predominant conduction mechanism is found to be variable range hopping between localized states, resulting in macroscopic semiconducting behaviour. The results of electrical and structural properties of the doped (Bi, Pb)-2212 compounds suggest that the decrease of charge carrier concentration and the induced structural disorder are the more effective and dominant mechanisms in the origin of the metal to insulator transition and suppression of superconductivity due to Eu substitution at its Sr site. 展开更多
关键词 (Bi Pb)-2212 superconductor metal to insulator transition variable range hopping electrical properties
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Smart decontamination device for small-size radioactive scrap metal:using abrasion pin in rotating magnetic field and ultrasonic wave cleaner
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作者 Yongho Hong Suri Park +1 位作者 Sangwook Han Byungjick Kim 《Journal of Measurement Science and Instrumentation》 CAS 2013年第3期302-306,共5页
A smart decontamination device is developed for small-size radioactive scrap metal(SSRSM)arisen from nuclear facilities.The abrasion pin in rotating magnetic field and ultrasonic wave cleaner are used for solving the ... A smart decontamination device is developed for small-size radioactive scrap metal(SSRSM)arisen from nuclear facilities.The abrasion pin in rotating magnetic field and ultrasonic wave cleaner are used for solving the problems of the second decontamination and high treatment cost.At first,the decontamination efficiency of each device is improved by upgrading the design.Optimal operating conditions are determined for each device.Next,both techniques are applied sequentially.Experimental results show that the efficiency of combined decontamination device is higher than that of each device.With the use of the developed device,the various SSRSMs are decontaminated for 15 min treatment in magnetic abrasion device and15 min treatment in ultrasonic cleaning device.Decontamination index ranges from18 to 56.Absolute values of all decontaminated samples are below the background value. 展开更多
关键词 radioactive scrap metal DECONTAMINATION magnetic field ultrasonic cleaningCLC number:X771 Document code:AArticle ID:1674-8042(2013)03-0302-05
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一种R-C-R组合式12位逐次逼近A/D转换器 被引量:4
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作者 佟星元 陈杉 +2 位作者 蔡乃琼 朱樟明 杨银堂 《西安电子科技大学学报》 EI CAS CSCD 北大核心 2010年第5期904-910,共7页
采用一种R-C-R组合式逐次逼近A/D转换方法,基于UMC 90 nm CMOS工艺设计了一种12位1兆赫兹采样频率的逐次逼近型A/D转换器.在电路设计上,通过复用两段式电阻梯结构,有效地降低了系统对电容阵列的匹配性要求.在版图设计方面,采用了特殊的... 采用一种R-C-R组合式逐次逼近A/D转换方法,基于UMC 90 nm CMOS工艺设计了一种12位1兆赫兹采样频率的逐次逼近型A/D转换器.在电路设计上,通过复用两段式电阻梯结构,有效地降低了系统对电容阵列的匹配性要求.在版图设计方面,采用了特殊的电阻梯版图设计方法来减小连接电阻的失配影响,并采用金属叉指电容来提高工艺兼容性以减小工艺成本.在3.3 V模拟电源电压和1.0 V数字电源电压下,测得微分非线性为0.78最低有效位.当采样速率为1兆采样点每秒,输入信号频率为10 kHz时,测得的有效位数为10.3,包括输出驱动在内,功耗不足10 mW.整个转换器的有源面积小于0.31 mm2,符合嵌入式片上系统的应用要求. 展开更多
关键词 A/D转换器 逐次逼近 两段式电阻梯 金属叉指电容 低成本
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Using fused filament fabrication to improve the tribocorrosion behaviour of 17-4 PH SS in comparison to other metal forming techniques
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作者 Cristina GARCÍA-CABEZÓN Juan Alfonso NARANJO +3 位作者 Celia GARCÍA-HERNÁNDEZ Cristina BERGES Gemma HERRANZ Fernando MARTÍN-PEDROSA 《Friction》 SCIE EI CAS CSCD 2024年第10期2325-2343,共19页
Fused filament fabrication(FFF)is one of the additive manufacturing processes which has gained more interest because of its simplicity and low-cost.This technology is similar to the conventional metal injection mouldi... Fused filament fabrication(FFF)is one of the additive manufacturing processes which has gained more interest because of its simplicity and low-cost.This technology is similar to the conventional metal injection moulding(MIM)process,consisting of the feedstock preparation of metal powder and polymer binders,followed by layer-by-layer 3D printing(FFF)or injection(MIM)to create green parts and,finally,debinding and sintering.Moreover,both technologies provide near-dense parts.This work presents an in-depth study of the processing method’s influence.The porosity,microstructure,hardness,corrosion,and tribocorrosion behaviour are compared for 17-4 PH SS samples processed from powder by additive manufacturing using FFF and MIM,as well as conventional powder metallurgy(PM)samples.MIM samples exhibited the highest macro and microhardness,while corrosion behaviour was similar for both MIM and FFF samples,but superior in comparison to conventional PM samples.However,the FFF-as fabricated samples displayed a significant improvement in tribocorrosion resistance that could be explained by the higher proportion of delta ferrite and retained austenite in their microstructure. 展开更多
关键词 17-4 PH SS fused filament fabrication(FFF) metal injection moulding(MIM) corrosion behaviour powder metallurgy(PM) tribocorrosion behaviour
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Influencing factors on as-cast and heat treated 400-18 ductile iron grade characteristics 被引量:11
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作者 I.Riposan M.Chisamera S.Stan 《China Foundry》 SCIE CAS 2007年第4期300-303,共4页
As-cast and heat-treated 400-18 ductile iron (DI) grade was obtained in different foundry conditions, as metallic charge, Mg-treatment alloy and inoculation. It was found that the Pearlitic Influence Factor (P) an... As-cast and heat-treated 400-18 ductile iron (DI) grade was obtained in different foundry conditions, as metallic charge, Mg-treatment alloy and inoculation. It was found that the Pearlitic Influence Factor (P) and Anti- nodulizing Complex Factor (K1) have an important influence on property of DI, depending on the Mn and P level, the metallurgical quality of iron melt, rare earth (RE) and inoculation. It was also found that the influence of Mn is depended on the phosphorus and residual elements level in ductile iron. Less than 0.03%P and 0.2%Mn and P〈2.0 are the basic conditions to obtain as-cast ferritic structure. At the same lower level of Mn and P, the increasing of residual elements (P〉2.0) determines presence of pearlite in as-cast structure, while ferrite structure is obtained after a short annealing heat treatment. Lower level of phosphorus (P〈0.025%) and residual elements (Px〈2.0) allow to use relative high Mn content (0.32%-0.38%), in condition of ferritic structure, including in as-cast state. High P (0.04%- 0.045%) and Mn (0.25%-0.35%) content stabilized peadite, especially at lower level of residual elements (P 〈2.0). Antinodulizing action of elements was counteracted up to K1=2.0 level, by RE included in Mg-treatment alloy, which are beneficial for K1〈1.2 and compulsory for K1〉1.2. Si has a significant influence on the mechanical properties of heat treated ductile irons: an important decreasing of elongation level and a moderate increasing of yield and tensile strength and their ratio in 150-170 HB typical hardness field. A typical final chemical composition for as-cast 400-18 ductile iron could include 3.5%-3.7%C, 2.4%-2.5%Si, max.0.18%Mn, max.0.025%P, max.0.01%S, 0.04%-0.05%Mg for Px〈1.5 and K1〈1.1. High purity pig iron, RE-bearing FeSiMg and powerful inoculant are also recommended. 展开更多
关键词 ductile iron 400-18 grade metallic charge pearliUc and anti-nodulizing factors CHEMISTRY
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Distribution,fractionation,and contamination assessment of heavy metals in offshore surface sediments from western Xiamen Bay,China 被引量:2
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作者 Qiuli Yang Gongren Hu +2 位作者 Ruilian Yu Haixing He Chengqi Lin 《Acta Geochimica》 EI CAS CSCD 2016年第4期355-367,共13页
Surface sediment samples were collected at 21 offshore sites in western Xiamen Bay, Southeast China. Total concentrations of Li, V, Cr, Co, Ni, Cu, Zn, St, Mn, Pb, Ba, Fe, and Ti were determined by inductively coupled... Surface sediment samples were collected at 21 offshore sites in western Xiamen Bay, Southeast China. Total concentrations of Li, V, Cr, Co, Ni, Cu, Zn, St, Mn, Pb, Ba, Fe, and Ti were determined by inductively coupled plasma-optical emission spectrometry; Hg was determined by atomic fluorescence spectrometry. A modified BCR sequential extraction procedure was used to extract fractions of the above elements. Concentrations of Pb, Cr, and Hg at most sites met the primary standard criteria of Marine Sediment Quality except site S12 for Pb and S7 for Cr, while concentrations of Zn at 17 sites and Cu at seven sites exceeded the criteria. The mean concentration of Hg was three times higher than the background, with a possible source being the Jiulong River. Fe, Ti, Ba, Co, V, and Li dominated the residual phase, mainly from terrestrial input. Ni, Cr, Pb, and Hg in the non-residual phase varied largely between sites. Sr, Mn, Cu, and Zn were mainly in the non- residual fraction. Most sites showed considerable ecological risk; exceptions were site S7 (very high) and sites S10, S11, and S14 (moderate). Cu showed moderate-to-high pollution and Pb exhibited no-to-low pollution, while other metals had a non-pollution status according to their ratios of secondary phase to primary phase (RSP). Results of two assessment methods showed moderate pollution and a very high ecological risk for Cu, Zn, Ni, and Cr at site S7, which might be due to the local sewage treatment plant. 展开更多
关键词 Heavy metal Fractionation - Assessment Sediments DISTRIBUTION Western Xiamen Bay
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The effects of relative density of metal foams on the stresses and deformation of beam under bending 被引量:1
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作者 Aiyu Zhu Tianyou Fan Department of Mathematics,School of Science,Beijing Institute of Technology,P.O.Box 327,Beijing 100081,China Department of Physics,School of Science,Beijing Institute of Technology,P.O.Box 327,Beijing 100081,China 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 2007年第4期409-414,共6页
The exact analytic solution of the pure bending beam of metallic foams is given. The effects of relative density of the material on stresses and deformation are revealed with the Triantafillou and Gibson constitutive ... The exact analytic solution of the pure bending beam of metallic foams is given. The effects of relative density of the material on stresses and deformation are revealed with the Triantafillou and Gibson constitutive law (TG model) taken as the analysis basis. Several examples for individual foams are discussed, showing the importance of compressibility of the cellular materials. One of the objects of this study is to generalize Hill's solution for incompressible plasticity to the case of compressible plasticity, and a kinematics parameter is brought into the analysis so that the velocity field can be determined. 展开更多
关键词 metal foams - Relative density Compressible plasticity Constitutive law - TG model
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Assessment of trace metals contamination in stream sediments and soils in Abuja leather mining, southwestern Nigeria 被引量:1
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作者 Abiola Oyebamiji Adegbola Odebunmi +1 位作者 Hu Ruizhong Atta Rasool 《Acta Geochimica》 EI CAS CSCD 2018年第4期592-613,共22页
This study is aimed at determining the level of environmental degradation as well as the concentration of trace elements in soil and stream sediments in order to evaluate the environmental impact of the mining operati... This study is aimed at determining the level of environmental degradation as well as the concentration of trace elements in soil and stream sediments in order to evaluate the environmental impact of the mining operation.Twenty-five(25) soils and ten(10) stream sediment samples were collected from the study area. The physicochemical parameters were determined using appropriate instrumentation with the aid of a digital p H meter(Milwaukee meter) to measure the p H and electrical conductivity, total dissolved solids, moisture content and loss on ignition of the soil and stream sediment samples. The p H of the soil sample ranged from(6.10 to 7.19); Electrical conductivity ranged from(21.3 to 279.4 μS/cm), moisture content varied from(0.60% to 7.20%), and the LOI ranged from(2.03% to 18.62%). The results of the analysis showed that the concentrations of the trace elements in the soils and stream sediment samples were slightly higher than the background values. Plots of the trace elements in stream sediment samples show moderate, consistent decrease downstream except at points where there was mine water discharge into the main river. The pollution levels of heavy metals were examined in stream sediment and soil samples using different assessable indices, such as the enrichment factor, which showed significant-moderate enrichment for Cr, Th, Nb, Zn, Pb, Y and Zr and the geoaccumulation index, which showed practically moderate contamination with Cr, Ni and Sr based on regional background reference values. Geo-accumulation index and contamination index for soils and stream sediment revealed uncontaminated to moderate contamination. Likewise,elements with moderate contamination were Cr, Ni and Sr.The Pearson correlation showed that there were significant positive associations among selected metals in soil and stream sediment samples. 展开更多
关键词 Trace metals Stream sediments Geo-accumulation index - PCA Soil Southwestern Nigeria
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Hydrothermal Syntheses and Crystal Structures of Six Complexes Constructed from 1,3,5-Benzenetricarboxylic Acid and 4'-(4-Pyridyl)-2,2':6',2''-terpyridine Mixed Ligands 被引量:4
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作者 乔宇 王炫博 +4 位作者 周艳凤 刘力辉 车广波 刘春波 刘晓腾 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2017年第8期1381-1394,共14页
Six new transition metal complexes, [Zn(HBTC)(PYTPY)]n·n PYTPY(1), [Cu(HBTC)(PYTPY)]n·n PYTPY(2), [Co(HBTC)(PYTPY)]n·n DMF(3), [Mn(HBTC)(PYTPY)]n·n DMF(4), [Cd(HBTC)(PYTP... Six new transition metal complexes, [Zn(HBTC)(PYTPY)]n·n PYTPY(1), [Cu(HBTC)(PYTPY)]n·n PYTPY(2), [Co(HBTC)(PYTPY)]n·n DMF(3), [Mn(HBTC)(PYTPY)]n·n DMF(4), [Cd(HBTC)(PYTPY)(H2O)]n·2nH2O(5), and [Co(HBTC)(PYTPY)(H2O)2](6),(H3BTC = 1,3,5-benzenetricarboxylic acid, PYTPY = 4'-(4-pyridyl)-2,2':6',2''-terpyridine, DMF = N,N?-dimethylformamide), have been synthesized and characterized by elemental analysis, IR and X-ray single-crystal diffraction. Complexes 1~5 all feature one-dimensional chain structures, and complex 6 exhibits a zero-dimensional structure. Complexes 1~5 present three-dimensional(3D) supramolecular frameworks via π-π stacking interactions, whenas 6 has also a 3D supramolecular structure assembled by hydrogen bonding. Meanwhile, complexes 1 ~ 6 exhibit the thermal stabilities and photoluminescent properties. 展开更多
关键词 transition metal complex 1 3 5-benzenetricarboxylic acid 4'-(4-pyridyl)-2 2' 6' 2''-terpyridine crystal structure
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Dynamic fracture toughness of high strength metals under impact loading:increase or decrease 被引量:5
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作者 Ze-Jian Xu Yu-Long Li 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 2011年第4期559-566,共8页
An elusive phenomenon is observed in previous investigations on dynamic fracture that the dynamic fracture toughness (DFT) of high strength metals always increases with the loading rate on the order of TPa.m1/2.s-1.... An elusive phenomenon is observed in previous investigations on dynamic fracture that the dynamic fracture toughness (DFT) of high strength metals always increases with the loading rate on the order of TPa.m1/2.s-1. For the purpose of verification, variation of DFT with the loading rate for two high strength steels commonly used in the aviation industry, 30CrMnSiA and 40Cr, is studied in this work. Results of the experiments are compared, which were conducted on the modified split Hopkinson pressure bar (SHPB) apparatus, with striker velocities ranging from 9.2 to 24.1 m/s and a constant value of 16.3 m/s for 30CrMnSiA and 40Cr, respectively. It is observed that for 30CrMnSiA, the crack tip loading rate increases with the increase of the striker velocity, while the fracture initiation time and the DFT simultaneously decrease. However, in the tests of 40Cr, there is also an increasing tendency of DFT, similar to other reports. Through an in-depth investigation on the relationship between the dynamic stress intensity factor (DSIF) and the loading rate, it is concluded that the generally increasing tendency in previous studies could be false, which is induced from a limited striker velocity domain and the errors existing in the experimental and numerical processes. To disclose the real dependency of DFT on the loading rate, experimentsneed to be performed in a comparatively large striker velocity range. 展开更多
关键词 Dynamic fracture. Fracture toughness Loadingrate effect - Hopkinson pressure bar High strength metal
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Characterization of Household Solid Waste in the Town of Abomey - Calavi in Benin 被引量:1
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作者 Nikita Topanou Mariane Domeizel +2 位作者 Jacques Fatombi Roger Gérard JOSSE Taofiki Aminou 《Journal of Environmental Protection》 2011年第6期692-699,共8页
Identification of waste characteristics is an important step towards improving waste recovery. The aim of this research was to determine the physical and physico-chemical characteristics of waste of Abomey–Calavi cit... Identification of waste characteristics is an important step towards improving waste recovery. The aim of this research was to determine the physical and physico-chemical characteristics of waste of Abomey–Calavi city and to study the relationship between standard of living and average ratio of daily waste generated by each person. In this study the methodology used French standards to characterize particle size and typology of solid waste generated by the population of Calavi City in Benin, West Africa. According to home criteria, the study area was stratified into three distinct levels of standard of living called: high standing, medium standing and low standing;Waste from 60 households was weighed daily. The total waste produced by each household was collected seven (7) days a week, for a period of three weeks. Waste characterization was performed using ratio, size granulometry and typological composition. Physico- Chemical analysis including organic mater, pH, Total Organic Carbon, total Kjeldahl nitrogen and metal trace element were also performed. To better assess waste compostability, water extractable organic matter was quantified and qualitative identification was made with XAD8 and XAD4 resins. Results show that the amount of waste increases with the standard of living;the average ratio of daily waste generated is 0.89 kg day-1 person-1. Independently of the standard of living, fermentable compounds represent the largest proportion of waste materials (45%). Qualitative difference of waste content in organic matter is shown as a function of the population’s living standards. These results could be explained by a higher consumption of meat in the households with a higher standard of living, reflecting a greater proportion of transphilic (TPI), and hydrophilic (HPI) fractions. The C/N ratio is lower in the high standing households than in low ones. Metal trace element analysis showed a low but still significant pollution, whereas high iron and alu minum concentrations were found in all standings. In conclusion we propose a strategy for waste management in Abomey-Calavi based on sorting at the source to eliminate plastic waste and valorization of wastes via composting. 展开更多
关键词 Wastes- Standard of LIVING - Water Extractable Organic matter metal TRACE Element - XAD8/XAD4 RESINS
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Magnetic and Transport Properties of La_(0.5-x)Nd_xBa_(0.5) CoO_3 Compounds 被引量:1
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作者 张汝贞 刘宜华 +3 位作者 王成建 黄宝歆 季刚 梅良模 《Journal of Rare Earths》 SCIE EI CAS CSCD 2003年第5期558-562,共5页
Substituting effects of Nd for La in La 0.5 Ba 0.5 CoO 3 compounds were studied systematically. The results show that Nd doping does not change the itinerant properties of the Co3d electrons. The molecular ma... Substituting effects of Nd for La in La 0.5 Ba 0.5 CoO 3 compounds were studied systematically. The results show that Nd doping does not change the itinerant properties of the Co3d electrons. The molecular magnetic moment of the materials decreases monotonically with increasing Nd dopant. When Nd content x ≥0.45, a magnetic phase separation appears in the materials. When x ≤0.45, the Curie temperature decreases monotonically with increasing Nd dopant. This is due to the size effects of the rare earth ions. The electric resistance measurements show that in the studied temperature range, the conduction of the materials belongs to the thermo diffusion conduction below the Curie temperature, while it belongs to the variable range hopping conduction of polarons over the Curie temperature. 展开更多
关键词 metal materials La 0.5- x Nd x Ba 0.5 CoO 3 compounds size effect itinerant electrons charge transfer rare earths
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Rapid Expansion of Supercritical Solution of Poly (1,1,2,2- Tetrahy-droperfluorodecyl Acrylate)
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作者 董擎之 《Journal of China Textile University(English Edition)》 EI CAS 1999年第2期35-37,共3页
Poly(1,1,2,2- tetrahydroperfluorodecyl acrylate) (poly (TA-N)) was synthesized in laboratory. The resulting morphology of rapid expansion of supercritical solution (RESS) sprays of poly(TA - N) was investigated. At ap... Poly(1,1,2,2- tetrahydroperfluorodecyl acrylate) (poly (TA-N)) was synthesized in laboratory. The resulting morphology of rapid expansion of supercritical solution (RESS) sprays of poly(TA - N) was investigated. At apre - expansion temperature of 45℃), amorphous polymer was formed. At temperature around 60 ℃ to 80 ℃ , fibers were formed. Increase of temperature increasesparticle size slightly. At temperature of 105℃ , most of particles are spheres. The RESS is an attractive process. To apply the polymers desired for coating applications in an organic solvent - free process that is economically viable , and it will have implications for pollution prevention during polymer film 展开更多
关键词 Rapid EXPANSION of SUPERCRITICAL solution ( RESS ) Poly( 1 1 2 2 - tetrahydroperfluorodecyl ACRYLATE ) Synthesis POROUS sintered metal plate .
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Multichip on Aluminum Metal Plate Technology for High Power LED Packaging
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作者 Choong-mo NAM Mi-hee JI 《Journal of Measurement Science and Instrumentation》 CAS 2010年第3期297-299,共3页
Multichip on Ahnnintnn Metal Plate(MOAMP) technology with simple structure and low thermal resistance is developed for effective heat reratrval of Light Emitting Diode(LED) p-n junction and LED lighting module to ... Multichip on Ahnnintnn Metal Plate(MOAMP) technology with simple structure and low thermal resistance is developed for effective heat reratrval of Light Emitting Diode(LED) p-n junction and LED lighting module to have high reliability. The thermal resistance of LED modules was numerical and experimental. Thermal resistance from the jtnction to aluminten metal plate, considering input power of IFD module using MOAMP technology, is 3.02 K/W, 3.23 K/W for the measured and calculated, respectively. We expect that the reported MOAMP technology with low thermal resistance will be a promising solution for high power LED fighting modules. 展开更多
关键词 - thermal resistance Light Emitting Diode (IFO) aluminum metal plate IHOAMP
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Two Fluorescent Complexes Assembled by Schiff Base 2-Methoxy-6-(phenyliminiomethyl) Phenolate Ligand
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作者 单亦韩 陈小菊 +1 位作者 秦毅 赵国良 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2013年第6期811-816,共6页
Two d10 metal complexes Zn(NCS)2(C14HI3NO2)2 (1) and [Cd(NO3)2(CI4HI3NO2)2]. 4H20 (2) assembled by 2-methoxy-6-(phenyliminiomethyl) phenolate ligand (C14H13NO2, HL) have been synthesized and characteri... Two d10 metal complexes Zn(NCS)2(C14HI3NO2)2 (1) and [Cd(NO3)2(CI4HI3NO2)2]. 4H20 (2) assembled by 2-methoxy-6-(phenyliminiomethyl) phenolate ligand (C14H13NO2, HL) have been synthesized and characterized by elemental analysis, IR and TG The single-crystal X-ray diffraction studies demonstrated that complex 1 crystallizes in monoclinic, P21/c space group with a = 17.321(7), b = 11.781(0), c = 15.593(2) A, fl = 110.273(6)°, V = 2984.95 A3, Z = 4, C30H26N404SzZn, Mr = 636.04, F(000) = 1312, Dc = 1.415 g/cm3,μ(MoKa) = 1.004 mm"1, the final R = 0.0403 and wR = 0.0900 for 21441 observed reflections with I 〉 20(/). Complex 2 is of monoclinic system, space group C2/c with a = 16.7767(2), b = 10.8989(2), c = 17.4928(2) A, fl = 90.614(9)°, V= 3198.37 A3, Z = 4, C28H34N4O14Cd, Mr= 731.25, F(000) = 1528, Dc = 1.568 g'cm^-3, μ(MoKa) = 0.757 mm-1, the final R = 0.0361 and wR = 0.0857 for 19811 observed reflections with I 〉 2σ(I). The two complexes were formed by Schiff base 2-methoxy-6-(phenyliminiomethyl) phenolate ligand and formed a 3D supramolecular architecture by π-πstacking interactions. Moreover, the complexes are luminescent in the solid state. These observations indicate that the complexes are promising system for the development of potential photoactive materials. 展开更多
关键词 d^10 metal complex 2-methoxy-6-(phenyliminiomethyl) phenolate ligand crystal structure luminescent
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Synthesis, Characterization of Mn2*, Co2*, Ni2*, Cu2* and Zn2. Complex Salts with 2,3,5-(Triphenyl) Tetrazolium Chloride and the Crystal Structure of [C N4( C6H5)3]2[C uC 14]
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作者 Nabeel Hadi Buttrus Jassim Mohammad Alyass Amera Faris Mohammad 《Journal of Chemistry and Chemical Engineering》 2013年第7期613-620,共8页
A series of new complex salts of the type [R]2[MC14] where R =[Ph-C=n-N-Ph N=N-Ph],M = Mn2+, Co2+, Ni2+, Cu2+ and Zn2+ wereprepared and characterized by elemental analysis, molar conductance, IR and UVNis is spec... A series of new complex salts of the type [R]2[MC14] where R =[Ph-C=n-N-Ph N=N-Ph],M = Mn2+, Co2+, Ni2+, Cu2+ and Zn2+ wereprepared and characterized by elemental analysis, molar conductance, IR and UVNis is spectral studies and magnetic measurements.The crystal structure of[Ph-C=n-N-Ph N=N-Ph]2[CuCl4] was determined by single crystal X-ray crystallography. The structure consisted of anion part and a 2,3,5-(triphenyl) tetrazolium cation as counter ions. The copper complex has a distorted tetrahedral geometry, the CI(1)-Cu-CI(2) [124.33 (2°)] and Cl(3)-Cu-Cl(4) [131.03 (2°)] angles are significantly larger than the ideal tetrahedral. The [CuCI4] anion and its counter ions are connected through a hydrogen bonds between C1 of the dianion and hetero aromatic rings by Cl-π, π-π and C-H … π, interactions. 展开更多
关键词 Complex salts transition metals 2 3 5-(triphenyl) tetrazolium cation.
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