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Progress on Transition Metal Ions Dissolution Suppression Strategies in Prussian Blue Analogs for Aqueous Sodium-/Potassium-Ion Batteries 被引量:1
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作者 Wenli Shu Junxian Li +3 位作者 Guangwan Zhang Jiashen Meng Xuanpeng Wang Liqiang Mai 《Nano-Micro Letters》 SCIE EI CAS CSCD 2024年第7期142-168,共27页
Aqueous sodium-ion batteries(ASIBs)and aqueous potassium-ion batteries(APIBs)present significant potential for large-scale energy storage due to their cost-effectiveness,safety,and environmental compatibility.Nonethel... Aqueous sodium-ion batteries(ASIBs)and aqueous potassium-ion batteries(APIBs)present significant potential for large-scale energy storage due to their cost-effectiveness,safety,and environmental compatibility.Nonetheless,the intricate energy storage mechanisms in aqueous electrolytes place stringent require-ments on the host materials.Prussian blue analogs(PBAs),with their open three-dimensional framework and facile synthesis,stand out as leading candidates for aqueous energy storage.However,PBAs possess a swift capacity fade and limited cycle longevity,for their structural integrity is compromised by the pronounced dis-solution of transition metal(TM)ions in the aqueous milieu.This manuscript provides an exhaustive review of the recent advancements concerning PBAs in ASIBs and APIBs.The dissolution mechanisms of TM ions in PBAs,informed by their structural attributes and redox processes,are thoroughly examined.Moreover,this study delves into innovative design tactics to alleviate the dissolution issue of TM ions.In conclusion,the paper consolidates various strategies for suppressing the dissolution of TM ions in PBAs and posits avenues for prospective exploration of high-safety aqueous sodium-/potassium-ion batteries. 展开更多
关键词 Prussian blue analogs Transition metal ions dissolution Suppression strategies Aqueous sodium-ion batteries Aqueous potassium-ion batteries
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Effect of high-energy Ne ions irradiation on mechanical properties difference between Zr_(63.5)Cu_(23)Al_(9)Fe_(4.5)metallic glass and crystalline W
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作者 李娜 张立松 +3 位作者 张小楠 宫丽悦 羌建兵 梅显秀 《Plasma Science and Technology》 SCIE EI CAS CSCD 2024年第6期14-21,共8页
In this paper,high-energy Ne ions were used to irradiate Zr_(63.5)Cu_(23)Al_(9)Fe_(4.5) metallic glass(MG)and crystalline W to investigate their difference in mechanical response after irradiation.The results showed t... In this paper,high-energy Ne ions were used to irradiate Zr_(63.5)Cu_(23)Al_(9)Fe_(4.5) metallic glass(MG)and crystalline W to investigate their difference in mechanical response after irradiation.The results showed that with the irradiation dose increased,the tensile micro-strain increased,nano-hardness increased from 7.11 GPa to 7.90 GPa and 8.62 GPa,Young’s modulus increased,and H3/E2 increased which indicating that the plastic deformability decreased in crystalline W.Under the same irradiation conditions,the Zr_(63.5)Cu_(23)Al_(9)Fe_(4.5) MG still maintained the amorphous structure and became more disordered despite the longer range and stronger displacement damage of Ne ions in Zr_(63.5)Cu_(23)Al_(9)Fe_(4.5) MG than in crystalline W.Unlike the irradiation hardening and embrittlement behavior of crystalline W,Zr_(63.5)Cu_(23)Al_(9)Fe_(4.5) MG showed the gradual decrease in hardness from 6.02 GPa to 5.89 GPa and 5.50 GPa,the decrease in modulus and the increase in plastic deformability with the increasing dose.Possibly,the irradiation softening and toughening phenomenon of Zr_(63.5)Cu_(23)Al_(9)Fe_(4.5) MG could provide new ideas for the design of nuclear materials. 展开更多
关键词 heavy ions irradiation displacement damage metallic glass crystalline W mechanical property
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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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Asymmetric Electrolytes Design for Aqueous Multivalent Metal Ion Batteries 被引量:1
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作者 Xiaochen Yang Xinyu Wang +2 位作者 Yue Xiang Longtao Ma Wei Huang 《Nano-Micro Letters》 SCIE EI CSCD 2024年第3期227-253,共27页
With the rapid development of portable electronics and electric road vehicles,high-energy-density batteries have been becoming front-burner issues.Traditionally,homogeneous electrolyte cannot simultaneously meet diame... With the rapid development of portable electronics and electric road vehicles,high-energy-density batteries have been becoming front-burner issues.Traditionally,homogeneous electrolyte cannot simultaneously meet diametrically opposed demands of high-potential cathode and low-potential anode,which are essential for high-voltage batteries.Meanwhile,homogeneous electrolyte is difficult to achieve bi-or multi-functions to meet different requirements of electrodes.In comparison,the asymmetric electrolyte with bi-or multi-layer disparate components can satisfy distinct requirements by playing different roles of each electrolyte layer and meanwhile compensates weakness of individual electrolyte.Consequently,the asymmetric electrolyte can not only suppress by-product sedimentation and continuous electrolyte decomposition at the anode while preserving active substances at the cathode for high-voltage batteries with long cyclic lifespan.In this review,we comprehensively divide asymmetric electrolytes into three categories:decoupled liquid-state electrolytes,bi-phase solid/liquid electrolytes and decoupled asymmetric solid-state electrolytes.The design principles,reaction mechanism and mutual compatibility are also studied,respectively.Finally,we provide a comprehensive vision for the simplification of structure to reduce costs and increase device energy density,and the optimization of solvation structure at anolyte/catholyte interface to realize fast ion transport kinetics. 展开更多
关键词 Asymmetric electrolyte Aqueous multivalent metal ion batteries Electrochemical stability windows Electrolyte interface
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Progress in doping and crystal deformation for polyanions cathode based lithium-ion batteries
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作者 Sajeela Awasthi Srikanta Moharana +6 位作者 Vaneet Kumar Nannan Wang Elham Chmanehpour Anupam Deep Sharma Santosh K.Tiwari Vijay Kumar Yogendra Kumar Mishra 《Nano Materials Science》 EI CAS CSCD 2024年第5期504-535,共32页
Polyanion-based materials are considered one of the most attractive and promising cathode materials for lithiumion batteries(LIBs)due to their good stability,safety,cost-effectiveness,suitable voltages,and minimal env... Polyanion-based materials are considered one of the most attractive and promising cathode materials for lithiumion batteries(LIBs)due to their good stability,safety,cost-effectiveness,suitable voltages,and minimal environmental impact.However,these materials suffer from poor rate capability and low-temperature performance owing to limited electronic and ionic conductivity,which restricts their practical applicability.Recent developments,such as coating material particles with carbon or a conductive polymer,crystal deformation through the doping of foreign metal ions,and the production of nanostructured materials,have significantly enhanced the electrochemical performances of these materials.The successful applications of polyanion-based materials,especially in lithium-ion batteries,have been extensively reported.This comprehensive review discusses the current progress in crystal deformation in polyanion-based cathode materials,including phosphates,fluorophosphates,pyrophosphates,borates,silicates,sulfates,fluorosilicates,and oxalates.Therefore,this review provides detailed discussions on their synthesis strategies,electrochemical performance,and the doping of various ions. 展开更多
关键词 Crystal deformation in polyanions metal ions doping Cathode materials Surface modification Lithium-ion batteries
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Imide-pillared covalent organic framework protective films as stable zinc ion-conducting interphases for dendrite-free Zn metal anodes
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作者 Xiaoman Ye Xuemei Xiao +3 位作者 Zhijing Wu Xin Wu Lin Gu Sheng Liu 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第10期470-477,I0010,共9页
The notorious growth of zinc dendrite and the water-induced corrosion of zinc metal anodes(ZMAs)restrict the practical development of aqueous zinc ion batteries(AZIBs).In this work,a zinc metallized,imide-pillared cov... The notorious growth of zinc dendrite and the water-induced corrosion of zinc metal anodes(ZMAs)restrict the practical development of aqueous zinc ion batteries(AZIBs).In this work,a zinc metallized,imide-pillared covalent organic framework(ZPC)protective film has been engineered as a stable Zn^(2+)ion-conducting interphase to modulate interfacial kinetics and suppress side reactions for ZMAs.Compared to bare Zn,ZPC@Zn exhibits a higher Zn^(2+)ionic conductivity,a larger Zn^(2+)transference number,a lower electronic conductivity,a smaller desolvation activation energy and correspondingly a significant suppression of corrosion,hydrogen evolution and Zn dendrites.Impressively,the ZPC@Zn||ZPC@Zn symmetric cell obtains a cycling lifespan over 3000 h under 5 mA cm^(-2)for 1 mA h cm^(-2).The ZPC@Zn||NH_(4)V_(4)O_(10)coin-type full battery delivers a specific capacity of 195.8 mA h g^(-1)with a retention rate of78.5%at 2 A g^(-1)after 1100 cycles,and the ZPC@Zn||NH_(4)V_(4)O_(10) pouch full cell shows a retention of70.1%in reversible capacity at 3 A g^(-1)after 1100 cycles.The present incorporation of imide-linked covalent organic frameworks in the surface modification of ZMAs will offer fresh perspectives in the search for ideal protective films for the practicality of AZIBs. 展开更多
关键词 Aqueous zinc ion batteries Zinc metal anodes Surface modification Covalent organic frameworks Imide linkage
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A layered multifunctional framework based on polyacrylonitrile and MOF derivatives for stable lithium metal anode
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作者 Fanfan Liu Peng Zuo +5 位作者 Jing Li Pengcheng Shi Yu Shao Linwei Chen Yihong Tan Tao Ma 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第6期282-288,I0007,共8页
Composite Li metal anodes based on three-dimensional(3D) porous frameworks have been considered as an effective material for achieving stable Li metal batteries with high energy density.However,uneven Li deposition be... Composite Li metal anodes based on three-dimensional(3D) porous frameworks have been considered as an effective material for achieving stable Li metal batteries with high energy density.However,uneven Li deposition behavior still occurs at the top of 3D frameworks owing to the local accumulation of Li ions.To promote uniform Li deposition without top dendrite growth,herein,a layered multifunctional framework based on oxidation-treated polyacrylonitrile(OPAN) and metal-organic framework(MOF) derivatives was proposed for rationally regulating the distribution of Li ions flux,nucleation sites,and electrical conductivity.Profiting from these merits,the OPAN/carbon nano fiber-MOF(CMOF) composite framework demonstrated a reversible Li plating/stripping behavior for 500 cycles with a stable Coulombic efficiency of around 99.0% at the current density of 2 mA/cm~2.Besides,such a Li composite anode exhibited a superior cycle lifespan of over 1300 h under a low polarized voltage of 18 mV in symmetrical cells.When the Li composite anode was paired with LiFePO_(4)(LFP) cathode,the obtained full cell exhibited a stable cycling over 500 cycles.Moreover,the COMSOL Multiphysics simulation was conducted to reveal the effects on homogeneous Li ions distribution derived from the above-mentioned OPAN/CMOF framework and electrical insulation/conduction design.These electrochemical and simulated results shed light on the difficulties of designing stable and safe Li metal anode via optimizing the 3D frameworks. 展开更多
关键词 Lithium metal anode Layered multifunctional framework ions flux redistribution Electrical insulation/conduction structure Uniform Li deposition
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Revealing alkali metal ions transport mechanism in the atomic channels of Au@a-MnO_(2)
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作者 Jingzhao Chen Yong Su +20 位作者 Hongjun Ye Yushu Tang Jitong Yan Zhiying Gao Dingding Zhu Jingming Yao Xuedong Zhang Tingting Yang Baiyu Guo Hui Li Qiushi Dai Yali Liang Jun Ma Bo Wang Haiming Sun Qiunan Liu Jing Wang Congcong Du Liqiang Zhang Yongfu Tang Jianyu Huang 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2023年第7期350-358,I0008,共10页
Understanding alkali metal ions’(e.g.,Li^(+)/Na^(+)/K^(+))transport mechanism is challenging but critical to improving the performance of alkali metal batteries.Herein using a-MnO_(2)nanowires as cathodes,the transpo... Understanding alkali metal ions’(e.g.,Li^(+)/Na^(+)/K^(+))transport mechanism is challenging but critical to improving the performance of alkali metal batteries.Herein using a-MnO_(2)nanowires as cathodes,the transport kinetics of Li^(+)/Na^(+)/K^(+)in the 2×2 channels of a-MnO_(2)with a growth direction of[001]is revealed.We show that ion radius plays a decisive role in determining the ion transport and electrochemistry.Regardless of the ion radii,Li^(+)/Na^(+)/K^(+)can all go through the 2×2 channels of a-MnO_(2),generating large stress and causing channel merging or opening.However,smaller ions such as Li^(+)and Na^(+)cannot only transport along the[001]direction but also migrate along the<110>direction to the nanowire surface;for large ion such as K^(+),diffusion along the<110>direction is prohibited.The different ion transport behavior has grand consequences in the electrochemistry of metal oxygen batteries(MOBs).For Li-O_(2)battery,Li^(+)transports uniformly to the nanowire surface,forming a uniform layer of oxide;Na^(+)also transports to the nanowire surface but may be clogged locally due to its larger radius,therefore sporadic pearl-like oxides form on the nanowire surface;K^(+)cannot transport to the nanowire surface due to its large radius,instead,it breaks the nanowire locally,causing local deposition of potassium oxides.The study provides atomic scale understanding of the alkali metal ion transport mechanism which may be harnessed to improve the performance of MOBs. 展开更多
关键词 ion transport In-situ TEM STEM metal oxygen batteries metal ion batteries
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Dual-functional pyrene implemented mesoporous silicon material used for the detection and adsorption of metal ions
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作者 Jing Huang Honghui Cai +3 位作者 Qian Zhao Yunpeng Zhou Haibo Liu Jing Wang 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2023年第8期108-117,共10页
A fluorescent active organic–inorganic hybrid material Py N-SBA-15 was synthesized by implementing pyrene derivatives into mesoporous SBA-15 silica.Py N-SBA-15 had detection and removal functionalities toward Al^(3+)... A fluorescent active organic–inorganic hybrid material Py N-SBA-15 was synthesized by implementing pyrene derivatives into mesoporous SBA-15 silica.Py N-SBA-15 had detection and removal functionalities toward Al^(3+),Cu^(2+),and Hg^(2+).On the one hand,Py N-SBA-15 was used as a fluorescence sensor and displayed high sensitivity toward Al^(3+),Cu^(2+),and Hg^(2+)cations (limit of detection:8.0×10^(-7),1.1×10^(-7),and 2.9×10^(-6)mol·L^(–1),respectively) among various analytes with“turn-off”response.On the other hand,the adsorption studies for these toxic analytes (Cu^(2+),Hg^(2+),and Al^(3+)) showed that the ion removal capacity could reach up to 45,581,and 85 mg·g^(-1),respectively.Moreover,the Langmuir isotherm models were better fitted with the adsorption data,indicating that the adsorption was mono-layer adsorption.Kinetic analysis revealed that the adsorption process was well described by the pseudo-second-order kinetic model for Cu^(2+)and Hg^(2+)and pseudo-first-order kinetic model for Al^(3+).The prepared silica material could be reused in four recycles without significantly decreasing its adsorption capacity.Therefore,the Py N-SBA-15 material can serve as a promising candidate for the simultaneous rapid detection and efficient adsorption of metal ions. 展开更多
关键词 Dual function Nanomaterials Mesoporous silica metal ions Detection and adsorption
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Effects of heavy metal ions Cu^(2+)/Pb^(2+)/Zn^(2+)on kinetic rate constants of struvite crystallization
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作者 Guangyuan Chen Tong Zhou +5 位作者 Meng Zhang Zhongxiang Ding Zhikun Zhou Yuanhui Ji Haiying Tang Changsong Wang 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2023年第5期10-16,共7页
Struvite(MAP)crystallization technology is widely used to treat ammonia nitrogen in waste effluents of its simple operation and good removal efficiency.However,the presence of heavy metal ions in the waste effluents c... Struvite(MAP)crystallization technology is widely used to treat ammonia nitrogen in waste effluents of its simple operation and good removal efficiency.However,the presence of heavy metal ions in the waste effluents causes problems such as slow crystallization rate and small crystal size,limiting the recovery rate and economic value of the MAP.The present study was conducted to investigate the effects of concentrations of three heavy metal ions(Cu^(2+),Zn^(2+),and Pb^(2+))on the crystal morphology,crystal size,average growth rate,and crystallization kinetics of MAP.A relationship was established between the kinetic rate constant Ktcalculated by the chemical gradient model and the concentrations of heavy metal ions.The results showed that low concentrations of heavy metal ions in the solution created pits on the MAP surface,and high level of heavy metal ions generated flocs on the MAP surface,which were composed of metal hydroxides,thus inhibiting crystal growth.The crystal size,average growth rate,MAP crystallization rate,and kinetic rate constant Ktdecreased with the increase in heavy metal ion concentration.Moreover,the Ktdemonstrated a linear relationship with the heavy metal concentration ln(C/C~*),which provided a reference for the optimization of the MAP crystallization process in the presence of heavy metal ions. 展开更多
关键词 STRUVITE CRYSTALLIZATion Heavy metal ions KINETICS Kinetic modeling Kinetic rate constant
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Metal ions as effectual tools for cancer with traditional Chinese medicine
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作者 Lei Wang Yingqiu Xie +2 位作者 Sandugash Myrzagali Weiling Pu Erwei Liu 《Acupuncture and Herbal Medicine》 2023年第4期296-308,共13页
Malignant tumor has become a major threat affecting human health,and is one of the main causes of human death.Recent studies have shown that many traditional Chinese medicines(TCM)have good anti-tumor activity,which m... Malignant tumor has become a major threat affecting human health,and is one of the main causes of human death.Recent studies have shown that many traditional Chinese medicines(TCM)have good anti-tumor activity,which may improve the therapeutic effect of routine treatment and quality of life with lower toxicity.However,the efficacy of TCM alone for the treatment of tumors is limited.Metal ions are essential substances for maintaining normal physiological activities.This article summarized the multiple mechanisms in which metal ions are involved in the prevention and treatment of tumors in TCM. 展开更多
关键词 metal ions Traditional Chinese medicine Treatment modalities Tumor development
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Effect of mono-/divalent metal ions on the conductivity characteristics of DNA solutions transferring through a microfluidic channel
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作者 朱洁 薛菁 +3 位作者 赵伟 张琛 冯晓强 王凯歌 《Chinese Physics B》 SCIE EI CAS CSCD 2023年第11期161-167,共7页
Interactions between deoxyribonucleic acid(DNA) and metal ions are vital for maintaining life functions, however,there are still unsolved questions about its mechanisms. It is of great practical significance to study ... Interactions between deoxyribonucleic acid(DNA) and metal ions are vital for maintaining life functions, however,there are still unsolved questions about its mechanisms. It is of great practical significance to study these issues for medical chip design, drug development, health care, etc. In this investigation, the conductivity properties of λ-DNA solutions with mono-/divalent metal ions(Na+, K^(+), Mg^(2+), and Ca^(2+)) are experimentally studied as they are electrically driven through a 5 μm microfluidic channel. Experimental data indicate that the conductivities of λ-DNA solutions with metal ions(M+/M2+) basically tend to reduce firstly and then increase as the voltage increases, of which the turning points varied with the metal ions. When the voltage surpasses turning points, the conductivity of λ-DNA-M+solutions increases with the concentration of metal ions, while that of λ-DNA-M^(2+)solutions decrease. Moreover, the conductivity of λ-DNA-M^(2+)solutions is always smaller than that of λ-DNA-M+solutions, and with high-concentration M^(2+), it is even smaller than that of the λ-DNA solution. The main reasons for the above findings could be attributed to the polarization of electrodes and different mechanisms of interactions between metal ions and λ-DNA molecules. This investigation is helpful for the precise manipulation of single DNA molecules in micro-/nanofluidic space and the design of new biomedical micro-/nanofluidic sensors. 展开更多
关键词 MICROFLUIDICS interaction between deoxyribonucleic acid(DNA)and metal ions conductivity-voltage relations asymmetric electrodes
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Hyperpolarizabilities of alkaline-earth metal ions Be^+, Mg^+, and Ca^+
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作者 Dong Yin Yong-Hui Zhang +2 位作者 Cheng-Bin Li Ke-Lin Gao Ting-Yun Shi 《Science China(Physics,Mechanics & Astronomy)》 SCIE EI CAS CSCD 2016年第9期33-38,共6页
The knowledge of the hyperpolarizabilities of atoms and ions is helpful for the analysis of the high order effects of the frequency shifts in precision spectroscopy experiments. Liu et al. [Phys. Rev. Lett. 114, 2230... The knowledge of the hyperpolarizabilities of atoms and ions is helpful for the analysis of the high order effects of the frequency shifts in precision spectroscopy experiments. Liu et al. [Phys. Rev. Lett. 114, 223001 (2015)] proposed to establish all-optical trapped ion clocks using laser at the magic wavelength for clock transition. To evaluate the high-order frequency shifts in this new scheme of optical clocks, hyperpolarizabilities are needed, but absent. Using the finite field method based on the B-spline basis set and model potentials, we calculated the electric-field-dependent energy shifts of the ground and low-lying excited states in Be+, Mg+, and Ca+ in the field strength range of 0.0-6×10-5 a.u.. The scalar and tensor polarizabilities (α0, α2) and hyperpolarizabilities (Y0,Y2, 74) were deduced. The results of the hyperpolarizabilities for Be+ showed good agreement with the values in literature, implying that the present method can be applied for the effective estimation of the atomic hyperpolarizabilities, which are rarely reported but needed in experiments. The feasibility of optical trapping of Ca+ is discussed, and the contributions of hyperpolarizabilities to the transition frequency shift for Ca+ in the optical dipole trap are estimated using quasi-electrostatic approximation. 展开更多
关键词 HYPERPOLARIZABILITY alkaline-earth metal ion finite field method
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Blue-emissions Modulated by Packing Forces in Alkaline-earth Metal OrganicFrameworks Based on Thiophene-2,5-dicarboxylic: Structures and Theoretical Calculations
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作者 陈家越 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2018年第12期1960-1970,1846,共12页
Solvothermal reactions of Ca(NO), Sr(NO)with thiophene-2,5-dicarboxylic in DMF afforded two new inorganic-organic hybrid frameworks, [M(TDC)(DMF)]n(M = Ca(1), Sr(2), TDC = thiophene-2,5-dicarboxylic, DMF = N,N?-dimeth... Solvothermal reactions of Ca(NO), Sr(NO)with thiophene-2,5-dicarboxylic in DMF afforded two new inorganic-organic hybrid frameworks, [M(TDC)(DMF)]n(M = Ca(1), Sr(2), TDC = thiophene-2,5-dicarboxylic, DMF = N,N?-dimethylformamide), which have been characterized by single-crystal X-ray diffraction, powder X-ray diffraction, elemental analysis and IR spectra. Both compounds feature three-dimensional(3D) frameworks based on the versatile coordinated modes(μ-η~2:η~2, μ-η~2:η~1, μ-η~2:η~1) of carboxylic groups in tdc ligands. C–H···S hydrogen bonds and C–H···π interactions contribute to the stabilization of the structures. They exhibit weaker packing force compared with their literature isomers. Consequently, blue and blue/green luminescence of two compounds has been observed. Their luminescence mechanism can be ascribed to ligand-to-metal charge transfer(LMCT) compared with the ligand-centered luminescence in their isomers. Electronic structural calculations illustrate that under the condition of weaker packing forces, larger gaps can be achieved, which facilitate the LMCT. This work suggests that the introduction of S-heteroatom can result in more electrons rich in the metal centers, thus giving rise to metal-involved luminescence. 展开更多
关键词 alkaline-earth metal complex thiophene-2 5-dicarboxylic photoluminescence theoretical calculation
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Effect of metallic ions on dispersibility of fine diaspore 被引量:4
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作者 周瑜林 胡岳华 王毓华 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2011年第5期1166-1171,共6页
Dispersion experiments were conducted to study the influence of metallic cations on the dispersibility of diaspore. The reaction mechanisms were investigated based on the analysis of zeta (ξ) potential and calculat... Dispersion experiments were conducted to study the influence of metallic cations on the dispersibility of diaspore. The reaction mechanisms were investigated based on the analysis of zeta (ξ) potential and calculations of solution chemistry and DLVO theory. The results show that the valence of cations, instead of the cation type, plays an important role in the dispersibility of diaspore The impact of multivalent metallic cations is greater than that of monovalent cations. In the presence of Ca^2+ and Mg^2+, the dispersion of diaspore doesn't change in the range of pH value below 10. However, Ca^2+ and Mg^2+ may induce strong coagulation of particles when pH value is higher than 10. The adsorption of species of calcium and magnesium ions on diaspore can cause the compression of electric double layer, the decrease of the absolute value of zeta potential and the repulsion force between diaspore particles. The new IEP (isoelectric point) appeared at pH value of 11 may attribute to the adsorption of Mg(OH)2(s). 展开更多
关键词 DIASPORE metallic ions DISPERSIBILITY zeta potential DLVO theory
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Effects of Metal Ions and Organic Solvents on Alkaline Phosphatase from Rice-field Eel 被引量:7
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作者 黄毅 唐云明 《Agricultural Science & Technology》 CAS 2008年第2期112-115,共4页
[Objective]The mechanism of alkaline phosphatase(ALP) was studied to promote rice-field eel aquaculture industry. [ Method] The effects of effectors such as multiple metal ions and organic solvents on ALP in viscera... [Objective]The mechanism of alkaline phosphatase(ALP) was studied to promote rice-field eel aquaculture industry. [ Method] The effects of effectors such as multiple metal ions and organic solvents on ALP in viscera of rice-field eel. [ Result] Na^+ and K ^+ didn't generate big influences on enzyme activity;Mg^2+ and Ca^2+ could promote ALP while Li^+,Cu^2+ and Zn^2+ could restrain ALP enzyme activity. Both HPO4^2- and WO4^2- generated by en- zyme catalyzing disodium phenyl phosphate possessed strong inhibitory effects on emzymc, and 9.5 mmol/L HPO4^2 - would make enzyme activity decline by 13% while 9.5 mmol/L WO4^3- would make enzyme decline by 34%. The inhibition types of them were both competitive inhibition on enzyme activity. The organic solvents such as methanol, ethanol,ethylene glycol,isopropannl all generated influences on ALP and the order according to their inhibitory effects was isopropanol 〉 ethanol 〉 methanol 〉 ethylene glycol. [ Conclusion] The inflncnces of various effeetors on ALP aetivity of rice-field eel were studied from dynamics perspective to provide theoretical basis for further clarifying ALP mechanism. 展开更多
关键词 metal ion Organic solvent Alkaline phosphatase Rice-field eel
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Effects of Exogenous Amylases and Metal Ions on the Amylase Specific Activities and Starch Degradation of the Upper Leaves of ‘KRK_(26)' during Flue-curing 被引量:1
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作者 赵昶灵 崔国民 孟凡来 《Agricultural Science & Technology》 CAS 2014年第10期1676-1683,共8页
Objective] The aim of this study was to investigate the effects of exoge-nous amylases and Ca2+, Mn2+ and K+ on the amylase specific activities and starch degradation of the upper leaves of 'KRK26' planted in Yun... Objective] The aim of this study was to investigate the effects of exoge-nous amylases and Ca2+, Mn2+ and K+ on the amylase specific activities and starch degradation of the upper leaves of 'KRK26' planted in Yunnan Province during flue-curing. [Method] The amylase specific activities and starch degradation of the leaves were determined by using spectrophotometry. [Result] The 8 U/g exogenous α-amy-lase could improve the specific activity of the leaf α-amylase at yel owing and color-fixing stages, but could not at stem-drying stage, and similarly, the 80 U/g exoge-nous β-amylase could improved the specific activity of the leaf β-amylase at the yel owing stage and the early period of color-fixing stage. The leaf starch could be enhanced to degrade by the exogenous α- or β-amylases and the enhancing effect of the former was stronger than that of the later. 1.50 mg/ml Ca2+ improved the specific activity of the leaf (α+β)-amylase mainly due to its enhancing effect on the leaf α-amylase, and increased the starch degradation. 4 mmol/L Mn2+ inhibited the leaf α-amylase from yel owing to the early period of color-fixing and the β- and (α+β)-amylases from the yel owing to the later period of color-fixing, but enhanced the leafα-amylase from the later period of color-fixing to the later period of stem-drying and the β- and (α+β)-amylases at the later period of stem-drying. Meanwhile, Mn2+ ham-pered the starch degradation during yel owing, but promoted it from the early period of color-fixing to stem-drying. 1 mg/ml K+ enhanced the leaf α-, β- and (α+β)-amy-lases during the yel owing stage, but lowered them from the early period of color-fix-ing to the later period of stem-drying, and always inhibited the leaf starch degrada-tion. [Conclusion] The exogenous α-, β- amylases and Ca2+ of suitable concentra-tions could be used to treat the tobacco leaves before flue-curing to improve the leaf starch degradation during the curing. 展开更多
关键词 Exogenous amylases and metal ions Amylase specific activity Starchdegradation Upper leaves of flue-cured tobacco variety 'KRK26' Flue-curing
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Effect of Metal Ions on Protease Activities in the Intestines and Hepatopancreas of Red-white Ornamental Carp (Cyprinus carpio L)
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作者 郭永军 魏东 +4 位作者 白东清 闫珊珊 吴旋 宁博 陆建权 《Agricultural Science & Technology》 CAS 2010年第3期104-106,122,共4页
[Objective] The aim of this study was to study effects of metal ions on the protease activities in digestive tissues and gland of red-white ornamental carp(Cyprinus carpio L).[Method] Effects of four kinds of metal ... [Objective] The aim of this study was to study effects of metal ions on the protease activities in digestive tissues and gland of red-white ornamental carp(Cyprinus carpio L).[Method] Effects of four kinds of metal ions (K+,Na+,Mg2+ and Ca2+) on protease activities in hepatopancreas,foregut,midgut,hindgut of red-white ornamental carp were studied by enzyme analysis method.[Result] Effects of four kinds of metal ions on protease activities of red-white ornamental carp were different in the range of experimental concentration from 25 mmol/L to 150 mmol/L.K+ could promote protease activities in hepatopancreas and hindgut at different levels.Especially,K+ had the promoting effect at low-concentration level,but the inhibitory effect at high-concentration level in midgut and the inhibitory effect in foregut.Na+ had the promoting effect on protease activities in hepatopancreas,foregut and hindgut at different levels,but the inhibitory effect in midgut.Mg2+ and Ca2+ had the inhibitory effect on protease activities in intestinal and hepatopancreas at different levels.[Conclusion] This study provides basic data and theoretical foundation for researches on the digestive physiology of red-white ornamental carp or the development and optimization of compound feed. 展开更多
关键词 Red-white ornamental carp metal ions Protease activities
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Identification of DNA Damage Caused by Heavy Metal Ions with Small Molecular DNA
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作者 梅运军 张磊 +2 位作者 毕欢 谢炳辉 朱玉婵 《Agricultural Science & Technology》 CAS 2012年第2期292-294,共3页
[Objective] The aim was to establish a convenient and effective method to evaluate the toxicity of heavy metal ions by using small molecular DNA. [Method] pUC18 DNA which had exposed to the four heavy metal ions of Hg... [Objective] The aim was to establish a convenient and effective method to evaluate the toxicity of heavy metal ions by using small molecular DNA. [Method] pUC18 DNA which had exposed to the four heavy metal ions of Hg2+, Cr6+, Pb2+, Cd2+ was used to study the bioactivity of DNA; simultaneously, gel electrophoresis and hyperchromic effect were employed to detect the mechanism of DNA damage. [Result] The bioactivity of the exposed DNA was decreased and the influence degree was Hg2+Cr6+Pb2+Cd2+; the gel electrophoresis and hyperchromic effect proved that the main reason leading to reduce the bioactivity was DNA cross link, in the order pf Hg2+Cr6+Pb2+Cd2+. [Conclusion] The study indicated that pUC18 DNA could be used to assay the damage of DNA causing by heavy mental ions, which may be a potential, simple and effective tool to evaluate toxicity of heavy metal ions to DNA. 展开更多
关键词 Heavy metal ions DNA damage PUC18
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Control Effects of Several Metal Ions in Micronutrient Fertilizer on the Bulb Rot of Iphigenia indica Kunth.
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作者 甄莉 杨旭英 杨永红 《Plant Diseases and Pests》 CAS 2010年第6期28-29,67,共3页
[Objective] The control methods of the bulb rot of Iphigenia indica Kunth.caused by Fusarium orthoceras App.et Wr.var.longius (Sherb.) were explored.[Method] The effect of eight different kinds of metal ions on the ... [Objective] The control methods of the bulb rot of Iphigenia indica Kunth.caused by Fusarium orthoceras App.et Wr.var.longius (Sherb.) were explored.[Method] The effect of eight different kinds of metal ions on the pathogen was studied;the contents of seven different kinds of metal ions in rhizosphere soil and bulb were also determined.[Result] The results showed that when the concentration of Cu2+ or Mg2+ was greater than 1.0mg/L or the concentration of Zn2+ or Ca2+ was lower than 0.5mg/L,the growth of pathogen could be inhibited.The results also showed that the bulb could enrich K highly,enrich Zn and Mg,limit the absorption of Ca and Fe,and inhibit the absorption of Cu and Mn during the growth process of bulb in I.indica Kunth.[Conclusion] Micronutrient fertilizer containing Mg could be used to prevent and cure the bulb rot of I.indica Kunth. 展开更多
关键词 Iphigenia indica Kunth. ROT Fusarium orthoceras App.et Wr.var.longius (Sherb.) Wr. metal ion Inhibition
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