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Synthesis and Modulation of Low-Dimensional Transition Metal Chalcogenide Materials via Atomic Substitution 被引量:1
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作者 Xuan Wang Akang Chen +3 位作者 XinLei Wu Jiatao Zhang Jichen Dong Leining Zhang 《Nano-Micro Letters》 SCIE EI CAS CSCD 2024年第9期49-94,共46页
In recent years,low-dimensional transition metal chalcogenide(TMC)materials have garnered growing research attention due to their superior electronic,optical,and catalytic properties compared to their bulk counterpart... In recent years,low-dimensional transition metal chalcogenide(TMC)materials have garnered growing research attention due to their superior electronic,optical,and catalytic properties compared to their bulk counterparts.The controllable synthesis and manipulation of these materials are crucial for tailoring their properties and unlocking their full potential in various applications.In this context,the atomic substitution method has emerged as a favorable approach.It involves the replacement of specific atoms within TMC structures with other elements and possesses the capability to regulate the compositions finely,crystal structures,and inherent properties of the resulting materials.In this review,we present a comprehensive overview on various strategies of atomic substitution employed in the synthesis of zero-dimensional,one-dimensional and two-dimensional TMC materials.The effects of substituting elements,substitution ratios,and substitution positions on the structures and morphologies of resulting material are discussed.The enhanced electrocatalytic performance and photovoltaic properties of the obtained materials are also provided,emphasizing the role of atomic substitution in achieving these advancements.Finally,challenges and future prospects in the field of atomic substitution for fabricating low-dimensional TMC materials are summarized. 展开更多
关键词 Transition metal chalcogenides Atomic substitution ion exchange Low-dimensional materials Controllable synthesis
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Preliminary Studies on Base Substitutions and Repair of DNA Mismatch Damage Stimulated by Low Energy N^+ Ion Beam Implantation in Escherichia coli 被引量:4
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作者 谢传晓 郭金华 +1 位作者 程备久 余增亮 《Plasma Science and Technology》 SCIE EI CAS CSCD 2003年第1期1677-1682,共6页
Ever since the low energy N+ ion beam has been accepted that the mutation effects of ionizing radiation are attributed mainly to direct or indirect damage to DNA. Evidences based on naked DNA irradiation in support of... Ever since the low energy N+ ion beam has been accepted that the mutation effects of ionizing radiation are attributed mainly to direct or indirect damage to DNA. Evidences based on naked DNA irradiation in support of a mutation spectrum appears to be consistent, but direct proof of such results in vivo are limited. Using mutS, dam and/or dcm defective Eschericha coli imitator strains, an preliminary experimental system on induction of in vivo mutation spectra of low energy N+ ion beam has been established in this study. It was observed that the mutation rates of rifampicin resistance induced by N+ implantation were quite high, ranging from 9.2 x 10~8 to 4.9× 10~5 at the dosage of 5.2×1014 ions/cm2. Strains all had more than 90-fold higher mutation rate than its spontaneous mutation rate determined by this method. It reveals that base substitutions involve in induction of mutation of low energy nitrogen ion beam implantation. The mutation rates of mutator strains were nearly 500-fold (GM2929), 400-fold (GM5864) and 6-fold larger than that of AB1157. The GM2929 and GM5864 both lose the ability of repair DNA mismatch damage by virtue of both dam and dcm pathways defective (GM2929) or failing to assemble the repair complex (GM5864) respectively. It may explain the both strains had a similar higher mutation rate than GM124 did. It indicated that DNA cytosine methylase might play an important role in mismatch repair of DNA damage induced by N+ implantation. The further related research were also discussed. 展开更多
关键词 low energy N^+ ion beam base substitutions dam(DNA adenine methylase) dcm(DNA cytosine methylase) MUTS MMR (mismatch repair) Escherichia coli mutator strain
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Evidence for Base Substitutions and Repair of DNA Mismatch Damage Induced by Low Energy N^+ Ion Beam Implantation in E. coli
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作者 谢传晓 Guo +6 位作者 Jinhua Yao Jianmin Wu Lijun Yu Zengliang 《High Technology Letters》 EI CAS 2003年第2期1-6,共6页
Ever since the low energy N + ion beam has been accepted, the mutations of ionizing radiation are attributable mainly to avoidance of DNA damages repair. Evidences based on in vivo proof results are limited. Using the... Ever since the low energy N + ion beam has been accepted, the mutations of ionizing radiation are attributable mainly to avoidance of DNA damages repair. Evidences based on in vivo proof results are limited. Using the E.coli wild type and mutator strains, the mutant frequencies suggest that base substitutions in rpoB gene are induced by the N + implantation. A highly conserved region is selected to get the direct evidence for base substitutions by sequence of the high fidelity PCR amplification products in mutants. Most of the mutants (90.9%, 40/44) have at least one base substitution in the amplification region. The evidences for CG to TA (55%, 22/40), AT to GC (20%, 8/40) and TA to CG (5%, 2/40) transitions are identified. The transversions are AT to TA (15%, 6/40) and GC to CG (5%, 2/40). It is suggested that DNA cytosine methylase might play an important role in mismatch repair of DNA damage induced by N + implantation by analysis of the mutant frequencies of mutator strains. 展开更多
关键词 low energy N + ion beam base substitutions mismatch repair mutator strains
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Effect of Cu ion substitution on structural and dielectric properties of Ni-Zn ferrites 被引量:1
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作者 罗广圣 周卫平 +3 位作者 李建德 姜贵文 唐少龙 都有为 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2015年第11期3678-3684,共7页
A series of Cu-substituted Ni_(0.5-x)Cu_xZn_(0.5)Fe_2O_4(x=0.12,0.16,0.20,0.24 and 0.28) spinel ferrites were prepared by conventional ceramic method to investigate the effects of Cu compositional variation on the str... A series of Cu-substituted Ni_(0.5-x)Cu_xZn_(0.5)Fe_2O_4(x=0.12,0.16,0.20,0.24 and 0.28) spinel ferrites were prepared by conventional ceramic method to investigate the effects of Cu compositional variation on the structure and dielectric properties.XRD patterns demonstrate that all the samples are crystallized in single-phase cubic spinel structure and the lattice constant increases with increasing Cu content.White grains observed by SEM are Cu-rich phase.The dielectric constant versus frequency curve displays a normal dielectric behavior of spinel ferrites.While the frequency dependence of dielectric loss tangent is found to be abnormal,exhibiting a peak at certain frequency for all Cu-substituted Ni-Zn ferrites.A maximum of the resistivity is observed at x=0.2 due to the decrease of hopping electrons between Fe^(2+) and Fe^(3+) in per unit volume,which is in contrast with the Cu content dependence of dielectric constant and dielectric loss. 展开更多
关键词 FERRITE Cu ion substitution dielectric constant dielectric dispersion dielectric loss RESISTIVITY
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Effects of sodium substitution on properties of LiMn_2O_4 cathode for lithium ion batteries 被引量:5
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作者 郭华军 李向群 +3 位作者 何方勇 李新海 王志兴 彭文杰 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2010年第6期1043-1048,共6页
Na-doped Li1.05Mn2O4 cathodes were synthesized using a sol-gel process.The samples were characterized by X-ray diffractometry(XRD),cyclic voltammetry(CV),electrochemical impedance spectroscopy(EIS)and charge-discharge... Na-doped Li1.05Mn2O4 cathodes were synthesized using a sol-gel process.The samples were characterized by X-ray diffractometry(XRD),cyclic voltammetry(CV),electrochemical impedance spectroscopy(EIS)and charge-discharge measurements. The results show that all the samples exhibit the same cubic spinel phase structure without impurity.The lattice constant and unit cell volume decrease with increasing the sodium dopant amount.As the molar ratio of sodium to manganese(x=n(Na)/n(Mn))increases from 0 to 0.03,the initial discharge capacity of the Li1.05Mn2O4 cathodes decreases from 119.2 to 107.9 mA·h/g,and the discharge capability at large current rate and the storage performance decline dramatically,while cycling performance at room temperature and 55℃are improved.The CV and EIS studies indicate that reversibility of Li1.05Mn2O4 cathodes decreases and the electrochemical impedance increases with increasing the sodium dopant amount. 展开更多
关键词 lithium ion battery CATHODE LIMN2O4 SODIUM substitution
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Studies on Electrophilic Substitution of Quasi-Aromatic Metal Ion Complexes
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作者 XIA Xiao-ping, HE Hai-ying and LI Ming (Department of Chemistry, Huazhong University of Science and Technology, Wuhan, 430074)ZHAO Cheng-xue (National Laborotory of Applied Organic Chemistry, Lanzhou University, Lanzhou, 730000) 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 1993年第4期282-287,共6页
The electrophilic substitution reaction occurring to the chelate ring of the complexes could be regarded as an indication of quasi-aromaticity of the ring systems, no catalyst was used and only triethylamine was emplo... The electrophilic substitution reaction occurring to the chelate ring of the complexes could be regarded as an indication of quasi-aromaticity of the ring systems, no catalyst was used and only triethylamine was employed, implying that the aroylating agents with different p-substituents are polarized enough to be effective electrophiles to attack the methine carbon of the electron-rich substrate 1. This property is probably the clue to polarization of the ligand electrons by the nickel( Ⅱ ) ion and to the participation of the nickel( Ⅱ ) in the π-bond systems of the two coordinated conjugated rings. The linearity relationship between vd-d maxima, E1/2OX(1) and σp are obtained, respectively. The electronic environment of central metal ion as well as the aromaticity of the ring system are affected by the electronic properties of the p-substituents. A comparison of the electrochemical results with each other showed .that when the electronegativity of the substituent was higher, the oxidation(Ni2+/Ni3+) becomes more difficult. 展开更多
关键词 Electrophilic substitution Quasi-aromatic metal ions Complex
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Nucleophilic Substitution of Halogenonitrobenzenes by Electrogenerated O_2- on Carbon Gas-diffusion-electrode
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作者 WANG Shu-fang, HUANG Chu-bao and ZHANG Dong (Department of Chemistry, Jilin University, Changchun, 130023) 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 1992年第4期473-476,共4页
Introduction The electrochemical reduction of O;was investigated widely during the past two decades. O;can react with various organic compounds. O;as a new synthesis reagent has been being explored.
关键词 Nucleophilic substitution . Superoxide ion O2 Carbon gas-diffusion-electrode
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Nucleophilic Aromatic Substitution of Nitrobenzenes with Nitrite Ion
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作者 Zhi Qiang ZHANG Zheng Hua TIAN (Anshan Institute of Iron & Steel Technology, Anshan 114002) 《Chinese Chemical Letters》 SCIE CAS CSCD 1997年第3期193-194,共2页
It is experimentally found that different renction courses exist when mtrite ion reacts with nitrobenzenes with different electron withdrawing groups. when it is substituted with strong electron withdrawing groups. se... It is experimentally found that different renction courses exist when mtrite ion reacts with nitrobenzenes with different electron withdrawing groups. when it is substituted with strong electron withdrawing groups. self-condensation in aprotic polar solvent occurs to give symmnetrical disubstituted diphenyl ethers. However. when it is substituted with moderate electron withdrawing groups, no diphenyl ethers are obtained under the same conditions, instead, corresponding carboxylates are yielded. As a result. the applicability of this reaction is distinctly clarified 展开更多
关键词 Nucleophilic Aromatic substitution of Nitrobenzenes with Nitrite ion
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Dual strategy of A-site ion substitution and self-assembled MoS_(2) wrapping to boost permittivity for reinforced microwave absorption performance 被引量:4
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作者 Ailing Feng Di Lan +2 位作者 Jinkun Liu Guanglei Wu Zirui Jia 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 2024年第13期1-11,共11页
With the rapid development of electronic technology,how to effectively eliminate electromagnetic pollu-tion has become a serious problem.Perovskite oxides have shown great potential in the field of electro-magnetic wa... With the rapid development of electronic technology,how to effectively eliminate electromagnetic pollu-tion has become a serious problem.Perovskite oxides have shown great potential in the field of electro-magnetic wave absorption due to their unique structure and excellent physicochemical properties.Herein,by rationally manipulating the A-site ion substitution strategy,the theoretically directed doping of Sr ions into La ionic sites was utilized and the layered MoS_(2) was loaded by the hydrothermal process to modify its surface.Consequently,the introduced polarization phenomenon improved the dielectric performance of the perovskite oxides,achieving a collaborative dielectric/magnetic loss mechanism.Accordingly,the prepared La0.7Sr0.3FeO3(LSFO)/MoS_(2) as coating filler in the epoxy resin coating system can obtain the minimum reflection loss of-67.09 dB at 1.9 mm and the maximum effective absorption bandwidth of 7.28 GHz at 2.3 mm.More importantly,it also exhibits excellent absorption performance for multi-band electromagnetic waves,covering a wide range of specified frequency bands.It provides inspiration for ex-ploring novel perovskite oxide-based electromagnetic wave absorbing coatings and broadens the choice of ideal candidate materials for designing highly efficient,multi-band absorbers to cope with sophisticated electromagnetic environments. 展开更多
关键词 Perovskite oxides A-site ion substitution MULTI-BAND Electromagnetic wave absorbing coating
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Photocatalytic Reduction of Cr^Ⅵ by Natural Sphalerite Suspensions under Visible Light Irradiation 被引量:15
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作者 LI Yan LU Anhuai WANG Changqiu 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2006年第2期267-272,共6页
The photocatalytic reductive capability of a natural semiconducting mineral, sphalerite has been studied for the first time. The sphalerite from the Huangshaping deposit of Hunan Province performed great photoreductiv... The photocatalytic reductive capability of a natural semiconducting mineral, sphalerite has been studied for the first time. The sphalerite from the Huangshaping deposit of Hunan Province performed great photoreductive capability that 91.95% of the Cr^6+ was reduced under 9 h visible light irradiation, higher than the 70.58% under 9.5 h UV light irradiation. The highly reductive ability results from its super negative potential of electrons in the conduction band. Furthermore, Fe substitution for Zn introduces donor states, and the oxidation process of Fe^2+ to Fe^3+ makes it an effective hole-scavenger. Cd and Cu substitute for Zn also reduce the bandgap and help broaden the absorbing edge towards the visible light. These substituting metal ions in natural sphalerite make it a hyper-active photocatalyst and very attractive for solar energy utilization. 展开更多
关键词 natural sphalerite PHOTOREDUCTion Cr^6+ visible light substituting ions bandgap
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VINYL RADICAL POLYMERIZATION INITIATED WITH CERIC ION AND N-(SUBSTITUTED PHENYL) ACETAMIDE SYSTEMS
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作者 丘坤元 鲁志华 +1 位作者 唐爱军 冯新德 《Chinese Journal of Polymer Science》 SCIE CAS CSCD 1992年第4期366-371,共6页
The polymerization of acrylamide (AAM)in H_2O/DMF or in H_2O/CH_3CN mixed solvent initiated with ceric ion (Ce^(4+) )/N-(substituted phenyl)-acetamide systems have been studied. The redox polymerization was revealed b... The polymerization of acrylamide (AAM)in H_2O/DMF or in H_2O/CH_3CN mixed solvent initiated with ceric ion (Ce^(4+) )/N-(substituted phenyl)-acetamide systems have been studied. The redox polymerization was revealed by the low value of overall activation energy (E_α) of AAM polymerization using ceric ion/N-(substituted phenyl) acetamide system as an initiator. The end group of polymer formed was detected by IR spectrum analysis method, it revealed the presence of N-(m-acetoxy-methylphenyl) acetamide (m-AAe) moiety end group in the polymer obtained with ceric ion/m-AAe initiation system. 展开更多
关键词 Ceric ion and N-(substituted phenyl)acetamide initiation systems Acrylamide and acrylonitrile radical polymerization IR spectrum end group analysis
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Sm-Cu离子取代锶铁氧体制备与磁性能研究 被引量:1
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作者 吴泽 张若男 金立国 《哈尔滨理工大学学报》 CAS 北大核心 2019年第3期112-116,共5页
采用固相法制备了Sm-Cu联合取代的锶铁氧体Sr1-xSmxFe12-xCuxO19(x=0.00-0.20)。利用XRD、SEM及VSM对锶铁氧体的晶相组成、微观形貌及磁学性能进行了研究。结果表明:随着掺杂量x的增加饱和磁化强度Ms,矫顽力Hc以及剩磁Mr均出现先增大后... 采用固相法制备了Sm-Cu联合取代的锶铁氧体Sr1-xSmxFe12-xCuxO19(x=0.00-0.20)。利用XRD、SEM及VSM对锶铁氧体的晶相组成、微观形貌及磁学性能进行了研究。结果表明:随着掺杂量x的增加饱和磁化强度Ms,矫顽力Hc以及剩磁Mr均出现先增大后减小的趋势;当Sm-Cu掺杂量x=0.05时,剩磁Mr达到最大值Mr=24.173 emu/g;当掺杂量x=0.10时,饱和磁化强度达到最大值Ms=51.757 emu/g,同时矫顽力也出现最大值Hc=809.904 Oe。 展开更多
关键词 锶铁氧体 sm-cu离子取代 固相法 磁性能
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钠离子电池锰基正极材料的元素替位掺杂改性研究进展
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作者 舒伟平 赵淑宁 +1 位作者 汪丽莉 刘烨 《现代化工》 CAS CSCD 北大核心 2024年第7期84-87,共4页
为提高钠离子电池锰基过渡金属氧化物正极材料的容量保持率,有效抑制循环过程中不可逆相变的发生,采用过渡金属位替代(M′-M)、碱金属位Li替代(Li-A)、过渡金属位以及碱金属位Li双取代(Li-M、A)的锰基TMO制备过程,利用较低线性有序性对... 为提高钠离子电池锰基过渡金属氧化物正极材料的容量保持率,有效抑制循环过程中不可逆相变的发生,采用过渡金属位替代(M′-M)、碱金属位Li替代(Li-A)、过渡金属位以及碱金属位Li双取代(Li-M、A)的锰基TMO制备过程,利用较低线性有序性对锰基TMO材料进行结构稳定改性。综合分析表明,锰基TMO材料经过不同元素过渡金属位替代、碱金属位替代、过渡金属位以及碱金属位Li双取代均不同程度抑制了Jahn-Teller效应。改性后的锰基TMO中过渡金属层间距和Na+扩散速率增大,容量保持率和结构稳定性得到显著提高,其中经碱金属Li元素掺杂后的锰基TMO容量保持率最高升至94.3%。 展开更多
关键词 元素替位掺杂 锰基过渡金属氧化物 钠离子电池
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Correlate phonon modes with ion transport via isotope substitution
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作者 Yirong Gao Jianxing Huang +1 位作者 Jun Cheng Shou-Hang Bo 《Science China Chemistry》 SCIE EI CAS CSCD 2023年第3期768-777,共10页
Understanding the correlations between lattice dynamics(phonons) and ion transport is important for improving the ionic conductivity of solid-state electrolytes. This understanding largely hinges on selective tuning o... Understanding the correlations between lattice dynamics(phonons) and ion transport is important for improving the ionic conductivity of solid-state electrolytes. This understanding largely hinges on selective tuning or excitation of specific phonon modes without changing the chemical environments of atoms, which is, however, challenging to be achieved. In this work, we used ~6Li isotope substitution to selectively change the phonon properties associated with lithium, without introducing additional defects or disorders which would affect the ion transport properties. The changes in the phonon modes were then related to ion transport properties through impedance measurements and deep potential molecular dynamics simulations. Our results demonstrated that lower lithium vibration frequency leads to higher ionic conductivity and lower activation energy in the garnet solid-state electrolyte of Li_(6.4)La_(3)Zr_(1.4)Ta_(0.6)O_(12). We furthermore quantified the effect of lithium-related phonons on the migration entropy and attempt frequency, which would be difficult to be achieved otherwise. Our work suggests an effective isotope substitution method to decouple the effect of phonon modes to ion transport from that of other complex structural factors. The obtained insights can contribute to innovative understanding of ion transport in solids and strategies to optimize the ionic conductivity of solid-state electrolytes. 展开更多
关键词 solid-state electrolytes phonon modes ion transport isotope substitution lattice dynamics
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生活垃圾焚烧灰渣代砂混凝土的抗氯离子渗透性能研究
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作者 贾伟龙 《广东建材》 2024年第4期27-30,共4页
为探究生活垃圾焚烧灰渣代砂混凝土的抗氯离子渗透性能,采用3种代砂率(0,20%,40%)和3种水胶比(0.30,0.45,0.60)进行配合比设计,并养护至标准、中长、长期龄期,基于电通量法测试不同配合比在不同龄期下的抗氯离子渗透性能。结果表明:与... 为探究生活垃圾焚烧灰渣代砂混凝土的抗氯离子渗透性能,采用3种代砂率(0,20%,40%)和3种水胶比(0.30,0.45,0.60)进行配合比设计,并养护至标准、中长、长期龄期,基于电通量法测试不同配合比在不同龄期下的抗氯离子渗透性能。结果表明:与普通混凝土类似,焚烧灰渣混凝土的抗氯离子渗透性能随着水胶比的增加而减少,焚烧灰渣代砂率的提高可促进抗氯离子渗透性能,且高水胶比下的效果更好;由于硫化物和氧化镁组分的存在,焚烧灰渣化学反应活性将在后期缓慢发挥,并进一步减少氯离子扩散系数;综合考虑环境效益,0.45水胶比+40%替代率下的具有最佳的抗氯离子渗透性能,可满足工程实践需求。 展开更多
关键词 焚烧灰渣 混凝土 替代率 龄期 抗氯离子渗透性能 电通量
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Multiferroic and in-plane magnetoelectric coupling properties of BiFeO_3 nano-films with substitution of rare earth ions La^(3+) and Nd^(3+) 被引量:6
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作者 郭凯鑫 张荣芬 +2 位作者 何腾鹏 孔汉东 邓朝勇 《Journal of Rare Earths》 SCIE EI CAS CSCD 2016年第12期1228-1234,共7页
Single-phase multiferroic BiFeO3 and Bi(0.9)(La/Nd)(0.1)FeO3(doped with rare earth ions La-(3+) and Nd-(3+)) films grown on(111)-Pt/Ti/SiO2/Si substrate were prepared via sol-gel method and a subsequen... Single-phase multiferroic BiFeO3 and Bi(0.9)(La/Nd)(0.1)FeO3(doped with rare earth ions La-(3+) and Nd-(3+)) films grown on(111)-Pt/Ti/SiO2/Si substrate were prepared via sol-gel method and a subsequent rapid thermal process. The phase composition, microstructure, ferroelectric, dielectric, ferromagnetic properties were investigated, and meanwhile, the in-plane magnetoelectric(ME) coupling effects of the films were reported and studied for the first time in this work. Structural characterization by X-ray diffraction and scanning electron microscopy showed that both BiFeO3 and Bi(0.9)(La/Nd)(0.1)FeO3 exhabited a rhombohedral structure with(111) preferred orientation. The results of the physical properties indicated that the introduction of rare earth ions improved significantly the polarization, magnetization and dielectric properties than the undoped BiFeO3 crystals, and it enhanced effectively the in-plane ME coupling(the ME coupling coefficient αE increased from 0.13 in the pure BiFeO3 to 0.21 in Bi(0.9)La(0.1)FeO3 and 0.34 V/(Oe·cm) in Bi(0.9)Nd(0.1)FeO3). The mechanism of these phenomena was investigated systematically. 展开更多
关键词 bismuth ferrite substitution rare earth ions FERROELECTRICITY DIELECTRICITY FERROMAGNETISM magnetoelectric coupling
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Effects of grinding environment and lattice impurities on spodumene flotation 被引量:5
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作者 Guang-li ZHU Yu-hua WANG +5 位作者 Xu-ming WANG Jan D. MILLER Dong-fang LU Xia-yu ZHENG Yue-hao ZHAO Hai-tao ZHENG 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2019年第7期1527-1537,共11页
The effect of grinding on the spodumene flotation was investigated. The flotation response of spodumene ground by different mills was different, due to the variation of metal ions on spodumene surfaces caused by grind... The effect of grinding on the spodumene flotation was investigated. The flotation response of spodumene ground by different mills was different, due to the variation of metal ions on spodumene surfaces caused by grinding environments and/or impurities. The samples were subjected to acid pickling treatment to remove most of the metal ions from the surfaces, and then all samples showed the same poor flotation response, which confirmed the significance of surface metal ions. Metal ion impurities may come from both grinding environments and lattice substitutions in spodumene. Density functional theory (DFT) calculation revealed that Fe and Ca could exist as lattice substitutions on the spodumene surface while Mg substitution is unlikely to occur. Furthermore, Fe is considered to be active site for the absorption of sodium oleate on the spodumene surface. Morphology analysis showed differences in particle size and shape for samples ground by different mills, resulting in different amounts of exposed surfaces. The particle size, cleavage characteristics caused by grinding environments, and metal ion impurities originated from grinding and isomorphous substitutions, play significant roles in the chemisorption of collector on the spodumene surface. 展开更多
关键词 GRINDING lattice substitution metal ion impurities density functional theory (DFT) calculation SPODUMENE CLEAVAGE FLOTATion
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Visible light responsive photocatalysts developed by substitution with metal cations aiming at artificial photosynthesis 被引量:2
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作者 Yuichi YAMAGUCHI Akihiko KUDO 《Frontiers in Energy》 SCIE CSCD 2021年第3期568-576,共9页
To solve resource,energy,and environmental issues,development of sustainable clean energy system is strongly required.In recent years,hydrogen has been paid much attention to as a clean energy.Solar hydrogen productio... To solve resource,energy,and environmental issues,development of sustainable clean energy system is strongly required.In recent years,hydrogen has been paid much attention to as a clean energy.Solar hydrogen production by water splitting using a photocatalyst as artificial photosynthesis is a promising method to solve these issues.Efficient utilization of visible light comprised of solar light is essential for practical use.Three strategies,i.e.,doping,control of valence band,and formation of solid solution are often utilized as the useful methods to develop visible light responsive photocatalysts.This minireview introduces the recent work on visible-light-driven photocatalysts developed by substitution with metal cations of those strategies. 展开更多
关键词 visible light responsive photocatalyst water splitting artificial photosynthesis:metal ion substitution
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The effect of electrochemically inactive Ti substituted for Ru in Li_(2)Ru_(1-x)Ti_xO_(3) on structure and electrochemical performance 被引量:1
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作者 Ye Yao Lu Zhang +5 位作者 Florian Sigel Bjorn Schwarz Helmut Ehrenberg Gang Chen Fei Du Chunzhong Wang 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2021年第9期222-228,共7页
The approach of substituting electrochemically active with inactive elements has widely been used to improve the electrochemical performance of Li-rich intercalation cathode materials. This especially is true for Li-r... The approach of substituting electrochemically active with inactive elements has widely been used to improve the electrochemical performance of Li-rich intercalation cathode materials. This especially is true for Li-rich compounds where almost all of the Li+ions are reversibly(de)intercalated during electrochemical cycling. The beneficial mechanism behind this substitution with electrochemically inactive elements is still not clear yet. Li_(2)RuO_(3) is chosen as basis for a model solid solution system to investigate the effect of electrochemically inactive elements owing to its high specific capacity of more than 300 m Ah g^(-1) and the significant contribution of anion redox mechanism. Herein, Li_(2)Ru_(1-x)Ti_xO_(3) solid solution series are synthesized and the effect of substituting with electrochemical inactive Ti for Ru on structure and electrochemical performance have been comprehensively investigated. The electrochemical performance is significantly improved, especially for Li_(2)Ru_(0.8)Ti_(0.2)O_(3), and the capacity retention after 50 cycles increases from 81% to 90%, as compared to the end member Li_(2)RuO_(3). Results of electrochemical impedance spectroscopy show that Ti substitution reduces the charge transfer impedance, which favors the Li+diffusion across the electrolyte–electrode interface and improves the electronic conductivity. For the first time,nuclear magnetic resonance was utilized to confirm that a small part of Ti ions exchange their position with Li ions in the Li layer. This research provides a better understanding of electrochemical inactive element substitution and strong insights for the functional design of the next generation of Li-rich cathode materials. 展开更多
关键词 Li_(2)Ru_(1-x)Ti_xO_(3) Lithium ion batteries Inactive element substitution XRD NMR
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Microstructural,magnetic and dielectric performance of rare earth ion(Sm^(3+))-doped MgCd ferrites
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作者 Dandan Wen Xia Chen +4 位作者 Dasen Luo Yi Lu Yixin Chen Renpu Li Wei Cui 《Chinese Physics B》 SCIE EI CAS CSCD 2022年第7期643-647,共5页
The combined effects of Sm^(3+)substitution together with the addition of 3 wt%Bi_(2)O_(3)endow Mg Cd ferrites with excellent magnetic permeability and dielectric permittivity.Various concentrations of Sm^(3+)(x=0,0.0... The combined effects of Sm^(3+)substitution together with the addition of 3 wt%Bi_(2)O_(3)endow Mg Cd ferrites with excellent magnetic permeability and dielectric permittivity.Various concentrations of Sm^(3+)(x=0,0.03,0.06,0.09,0.12and 0.15)were employed to modify the permeability(μ)and permittivity(ε)of the Mg Cd ferrites.X-ray diffraction,scanning electron microscopy(SEM),vibrating sample magnetometry and vector network analysis techniques were used to characterize the samples.The measurement results reveal that the ferrites processed a saturation magnetization of up to 36.8 emu/g and coercivity of up to 29.2 Oe via the conventional solid-state reaction method.The surface morphology SEM confirms that with increasing Sm^(3+)concentration,the grain shape changes from a polygon to a circle.Moreover,the dielectric permittivity can reach a value of 23.The excellent properties obtained in Sm^(3+)-substituted Mg ferrites suggest that they could be promising candidates for modern high-frequency antenna substrates or multilayer devices. 展开更多
关键词 ferrites Sm^(3+)ions substitution magnetic permeability dielectric permittivity
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