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Comparative study of nudged elastic band and molecular dynamics methods for diffusion kinetics in solid-state electrolytes
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作者 林啊鸣 石晶 +1 位作者 魏苏淮 孙宜阳 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第8期96-100,共5页
Considerable efforts are being made to transition current lithium-ion and sodium-ion batteries towards the use of solid-state electrolytes.Computational methods,specifically nudged elastic band(NEB)and molecular dynam... Considerable efforts are being made to transition current lithium-ion and sodium-ion batteries towards the use of solid-state electrolytes.Computational methods,specifically nudged elastic band(NEB)and molecular dynamics(MD)methods,provide powerful tools for the design of solid-state electrolytes.The MD method is usually the choice for studying the materials involving complex multiple diffusion paths or having disordered structures.However,it relies on simulations at temperatures much higher than working temperature.This paper studies the reliability of the MD method using the system of Na diffusion in MgO as a benchmark.We carefully study the convergence behavior of the MD method and demonstrate that total effective simulation time of 12 ns can converge the calculated diffusion barrier to about 0.01 eV.The calculated diffusion barrier is 0.31 eV from both methods.The diffusion coefficients at room temperature are 4.3×10^(-9) cm^(2)⋅s^(−1) and 2.2×10^(-9) cm^(2)⋅s^(−1),respectively,from the NEB and MD methods.Our results justify the reliability of the MD method,even though high temperature simulations have to be employed to overcome the limitation on simulation time. 展开更多
关键词 nudged elastic band method molecular dynamics solid electrolyte ion transport density func-tional theory
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Building and characterizing a stylus ion-trap system
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作者 崔太豪 魏雅琪 +8 位作者 李冀 袁泉 戴双晴 李沛东 周飞 张建奇 郑驻军 陈亮 冯芒 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第4期122-127,共6页
Cold trapped ions can be excellent sensors for ultra-precision detection of physical quantities,which strongly depends on the measurement situation at hand.The stylus ion trap,formed by two concentric cylinders over a... Cold trapped ions can be excellent sensors for ultra-precision detection of physical quantities,which strongly depends on the measurement situation at hand.The stylus ion trap,formed by two concentric cylinders over a ground plane,holds the promise of relatively simple structure and larger solid angle for optical access and fluorescence collection in comparison with the conventional ion traps.Here we report our fabrication and characterization of the first stylus ion trap constructed in China,aiming for studying quantum optics and sensing weak electric fields in the future.We have observed the stable confinement of the ion in the trapping potential for more than two hours and measured the heating rate of the trap to be dε/dt=7.10±0.13 meV/s by the Doppler recooling method.Our work starts a way to building practical quantum sensors with high efficiency of optical collection and with ultimate goal for contributing to future quantum information technology. 展开更多
关键词 stylus ion trap electric-field noises Doppler recooling method heating rate
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Lattice Boltzmann simulation study of anode degradation in solid oxide fuel cells during the initial aging process
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作者 Shixue Liu Zhijing Liu +1 位作者 Shuxing Zhang Hao Wu 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2024年第2期405-411,共7页
For present solid oxide fuel cells(SOFCs),rapid performance degradation is observed in the initial aging process,and the dis-cussion of the degradation mechanism necessitates quantitative analysis.Herein,focused ion b... For present solid oxide fuel cells(SOFCs),rapid performance degradation is observed in the initial aging process,and the dis-cussion of the degradation mechanism necessitates quantitative analysis.Herein,focused ion beam-scanning electron microscopy was em-ployed to characterize and reconstruct the ceramic microstructures of SOFC anodes.The lattice Boltzmann method(LBM)simulation of multiphysical and electrochemical processes in the reconstructed models was performed.Two samples collected from industrial-size cells were characterized,including a reduced reference cell and a cell with an initial aging process.Statistical parameters of the reconstructed microstructures revealed a significant decrease in the active triple-phase boundary and Ni connectivity in the aged cell compared with the reference cell.The LBM simulation revealed that activity degradation is dominant compared with microstructural degradation during the initial aging process,and the electrochemical reactions spread to the support layer in the aged cell.The microstructural and activity de-gradations are attributed to Ni migration and coarsening. 展开更多
关键词 solid oxide fuel cell anode degradation focused ion beam-scanning electron microscopy lattice Boltzmann method
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Evaluation of Clinical Efficacy of Wumen Acupuncture in the Adju-vant Treatment of Non-arteriticAnterior Ischemic Optic Neuropathy
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作者 Xin GU Guoqiang LIANG 《Medicinal Plant》 2024年第5期66-69,共4页
[Objectives]To explore the clinical efficacy of Wumen acupuncture in the adjuvant treatment of non-arteritic anterior ischemic op-tic neuropathy(NAION).[Methods]From June 2023 to April 2024,40 NAION patients were rand... [Objectives]To explore the clinical efficacy of Wumen acupuncture in the adjuvant treatment of non-arteritic anterior ischemic op-tic neuropathy(NAION).[Methods]From June 2023 to April 2024,40 NAION patients were randomly divided into treatment group(Wu-men acupuncture method+methylprednisolone sodium succinate+compound Danshen dripping pills orally)and control group(methylpred-nisolone sodium succinate+compound Danshen dripping pills orally).The clinical symptoms such as fundus condition and visual field were compared between the two groups before treatment,after 2 courses of treatment and 6 months after the first diagnosis.[Results](i)After 2 courses of treatment,the patients with optic disc edema in the treatment group were more than those in the control group,and the difference was significant(P<0.05).The number of patients with retinal hemorrhage in the treatment group was less than that in the control group,and the difference was significant(P<0.05).The color of the optic nerve in the treatment group was less than that in the control group,and the difference was not significant(P>0.05).(ii)Six months after the first diagnosis,the improvement of fundus in the treatment group was bet-ter than that in the control group(P<0.05).After 2 courses of treatment and 6 months after the first diagnosis,the visual evoked potential was significantly improved compared with the control group(P<0.05).After 2 courses of treatment and 6 months from the first diagnosis,the number of lines of visual acuity improvement in the treatment group was greater than that in the controlgroup(P<0.05).After 2 courses of treatment and 6 months from the first diagnosis,the average visual field defect in the treatment group was lower than that in the control group(P<0.05).[Conclusions]Wumen acupuncture method can significantly improve the symptoms of patients with non-arteritic anterior ische-mic optic neuropathy,which is worthy of clinical promotion. 展开更多
关键词 Wumen acupuncture method Adjuvant therapy Ischemic optic neuropathy(ion)
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Effects of synthesis conditions on the structural and electrochemical properties of layered LiNi_(1/3)Co_(1/3)Mn_(1/3)O_2 cathode material via oxalate co-precipitation method 被引量:6
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作者 TIAN Hua YE Naiqing +1 位作者 LIU Dan LI Wenqun 《Rare Metals》 SCIE EI CAS CSCD 2008年第6期575-579,共5页
The uniform layered LiNi1/3Co1/3Mn1/3O2 cathode material for lithium ion batteries was prepared by using (Ni1/3Co1/3Mn1/3)C2O4 as precursor synthesized via oxalate co-precipitation method in air. The effects of calc... The uniform layered LiNi1/3Co1/3Mn1/3O2 cathode material for lithium ion batteries was prepared by using (Ni1/3Co1/3Mn1/3)C2O4 as precursor synthesized via oxalate co-precipitation method in air. The effects of calcination temperature and time on the structure and electrochemical properties of the LiNi1/3Co1/3Mn1/3O2 were systemically studied. XRD results revealed that the optimal calcination conditions to prepare the layered LiNi1/3Co1/3Mn1/302 were 950℃ for 15 h. Electrochemical measurement showed that the sample prepared under the such conditions has the highest initial discharge capacity of 160.8 mAh/g and the smallest irreversible capacity loss of 13.5% as well as stable cycling performance at a constant current density of 30 mA/g between 2.5 and 4.3 V versus Li at room temperature. 展开更多
关键词 lithium ion batteries oxalate co-precipitation method cathode materials electrochemical performance
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Transition probabilities for NII 2p4f-2p3d and 2s2p^23d-2s2p^23p obtained by a semiclassical method 被引量:4
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作者 申晓志 袁萍 +1 位作者 张华明 王杰 《Chinese Physics B》 SCIE EI CAS CSCD 2007年第10期2934-2937,共4页
Based on NII spectra, some transition probabilities for 2p4f-2p3d and 2s2p23d-2s2p23p are obtained by a semi- classical method. The results are in good agreement with other measurements and the data reported by the Na... Based on NII spectra, some transition probabilities for 2p4f-2p3d and 2s2p23d-2s2p23p are obtained by a semi- classical method. The results are in good agreement with other measurements and the data reported by the National Institute of Standards and Technology. The transition probability for a line of 424.18nm is reported for the first time. Meanwhile, a feasible method of calculating transition parameters related to special excited configurations or highly excited states is provided. 展开更多
关键词 NII ion transition probability semiclassical method
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Cross-Linked Hollow Graphitic Carbon as Low-Cost and High-Performance Anode for Potassium Ion Batteries 被引量:5
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作者 Yanhong Feng Suhua Chen +2 位作者 Dongyang Shen Jiang Zhou Bingan Lu 《Energy & Environmental Materials》 SCIE EI CAS CSCD 2021年第3期451-457,共7页
Large-scale and low-cost preparation of carbon-based potassium anode with long life and high capacity is one of the footstones for the development of potassium ion batteries(PIBs).Herein,a low-cost carbon-based materi... Large-scale and low-cost preparation of carbon-based potassium anode with long life and high capacity is one of the footstones for the development of potassium ion batteries(PIBs).Herein,a low-cost carbon-based material,cross-linked hollow graphitic carbon(HGC),is large scale synthesized to apply for PIBs anode.Its hollow structure can afford sufficient space to overcome the damage caused by the volume expansion of graphitic carbon(GC).While the cross-linked structure forms a compact interconnection network that allows electrons to rapid transfer between different GC frameworks.Electrochemical measurements demonstrated that the HGC anode exhibited low charge/discharge plateau(about 0.25 V and 0.1 V)and excellent specific capacity as high as 298 m A h g^(-1)at the current density of 50 m A g^(-1).And more important,after 200 cycles the capacity of HGC anode still shows 269 m A h g^(-1)(the decay rate of per cycle is only 0.048%).Meanwhile,the use of commercial traditional electrolyte(KPF_(6))and cheap raw materials that provide new hope for trying and realizing the large-scale production of PIBs based on carbon anode materials. 展开更多
关键词 cross-linked hollow structure graphitic material high reversibility potassium ion battery
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Computation of one—dimensional consolidation of double layered ground using differential quadrature method 被引量:6
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作者 王宏志 陈云敏 黄博 《Journal of Zhejiang University Science》 EI CSCD 2003年第2期195-201,共7页
The authors give the solution to the problem of one-dimensional conso l idation of double-layered ground with the use of the differential quadrature me t hod. Case studies showed that the computational results for por... The authors give the solution to the problem of one-dimensional conso l idation of double-layered ground with the use of the differential quadrature me t hod. Case studies showed that the computational results for pore-water pressure in soil layer agreed with those of analytical solution; and that in the computat ional results for the interface of soil layer also agreed with those of the anal ytical solution except for the small discrepancies during shortly after the star t of computation. The advantages of the solution presented in this paper are tha t compared with the analytical solution, it avoids the cumbersome work in solvin g the transcendental equation for eigenvalues, and in the case of the Laplace transform s olution, it can resolve the precision problem in the numerical solution of long time inverse Laplace transform. Because of the matrix form of the solution in th is paper, it is convenient for formulating computational program for engineering practice. The formulas for calculating double-layered ground consolidation may be easily extended to the case of multi-layered soils. 展开更多
关键词 Double-layered ground One-dimensional consolidat ion Differential quadrature method
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Fluorescence properties of divalent and trivalent europium ions in CdWO_4 single crystals grown by the Bridgman method 被引量:1
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作者 胡皓阳 夏海平 +3 位作者 胡建旭 张约品 江浩川 陈红兵 《Chinese Physics B》 SCIE EI CAS CSCD 2013年第2期506-510,共5页
Optical absorption,excitation,and fluorescence were investigated in Eu ion-doped CdWO4 single crystal grown by a modified Bridgman method.The results indicate that Eu^2+ and Eu^3+ ions coexist in CdWO4 crystal and a... Optical absorption,excitation,and fluorescence were investigated in Eu ion-doped CdWO4 single crystal grown by a modified Bridgman method.The results indicate that Eu^2+ and Eu^3+ ions coexist in CdWO4 crystal and an energy transfer occurs between these Eu^2+ and Eu^3+ ions.When the crystal is excited by 266-nm light,the energy corresponding to the 4f65d to 8S7/2 transition of Eu^2+ ions results in the excitation of the Eu^3+ ions to the 5DJ level.The effect on fluorescence of annealing in oxygen at various temperatures was investigated.The excitation intensity of Eu^2+ ions at 266 nm decreases as annealing temperature increases from 300 K to 1073 K,but it remains at a certain equilibrium level when the annealing temperature is further increased. 展开更多
关键词 Eu^2+ ion optical spectra cadmium tungstate Bridgman method
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Preparation of Li[Ni_(1/3)Co_(1/3)Mn_(1/3)]O_2 powders for cathode material in secondary battery by solid-state method 被引量:1
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作者 PARK Sook Hee KANG Chan Hyoung 《Rare Metals》 SCIE EI CAS CSCD 2006年第z2期184-188,共5页
Employing Li2CO3, NiO, Co3O4, and MnCO3 powders as starting materials, Li[Ni1/3Co1/3Mn1/3]O2 was synthesized by solid-state reaction method. Various grinding aids were applied during milling in order to optimize the s... Employing Li2CO3, NiO, Co3O4, and MnCO3 powders as starting materials, Li[Ni1/3Co1/3Mn1/3]O2 was synthesized by solid-state reaction method. Various grinding aids were applied during milling in order to optimize the synthesis process. After successive heat treatments at 650 and 950 ℃, the prepared powders were characterized by X-ray diffraction (XRD) analysis, scanning electron microscopy, and transmission electron microscopy. The powders prepared by adding salt (NaCl) as grinding aid exhibit a clear R3m layer structure. The powders by other grinding aids like heptane show some impurity peaks in the XRD pattern. The former powders show a uniform particle size distribution of less than 1 μm average size while the latter shows a wide distribution ranging from 1 to 10 μm. Energy dispersive X-ray (EDX) analysiss show that the ratio of Ni, Co, and Mn content in the powder is approximately 1/3, 1/3, and 1/3, respecively. The EDX data indicate no incorporation of sodium or chlorine into the powders. Charge-discharge tests gave an initial discharge capacity of 160 mAh·g-1 for the powders with NaCl addition while 70 mAh·g-1 for the powders with heptane. 展开更多
关键词 lithium ion battery cathode materials layered structure solid-state method discharge density
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Preparation of LiTi_2(PO_4)_3 by the Sol-gel Method and Investigation of Its Formation Process 被引量:1
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作者 ZHU Jishun Tohge Noboru Minami Tsutomu 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 1999年第2期13-17,共5页
In this study,a novel solgel method has been developed to prepare LiTi2(PO4)3 lithium ion conductor as monophase at relatively low temperature(600).According to the XRD and IR analysis,the asprepared sample remained a... In this study,a novel solgel method has been developed to prepare LiTi2(PO4)3 lithium ion conductor as monophase at relatively low temperature(600).According to the XRD and IR analysis,the asprepared sample remained an amorphous state up to 500.The activation energy was calculated to be 252 kJ/mol according to the modified Kissinger equation. 展开更多
关键词 Lithium ion conductor LiTi2(PO4)3 Sol-gel method Crystallization process LiTi2(PO4)3 Solgel method Crystallization process
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Reformatted method for two-dimensional detector arrays measurement data in proton pencil beam scanning 被引量:2
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作者 Meng-Ya Guo Xiu-Fang Li +6 位作者 Jie Wang Qi Liu Xiu-Zhen Deng Man-Zhou Zhang Li-Ren Shen Yue-Hu Pu Zhi-Ling Chen 《Nuclear Science and Techniques》 SCIE EI CAS CSCD 2021年第6期83-93,共11页
The spatial resolution of a commercial two-dimensional(2D)ionization chamber(IC)array is limited by the size of the individual detector and the center-to-center distance between sensors.For dose distributions with are... The spatial resolution of a commercial two-dimensional(2D)ionization chamber(IC)array is limited by the size of the individual detector and the center-to-center distance between sensors.For dose distributions with areas of steep dose gradients,inter-detector dose values are derived by the interpolation of nearby detector readings in the conventional mathematical interpolation of 2D IC array measurements.This may introduce significant errors,particularly in proton spot scanning radiotherapy.In this study,by combining logfile-based reconstructed dose values and detector measurements with the Laplacian pyramid image blending method,a novel method is proposed to obtain a reformatted dose distribution that provides an improved estimation of the delivered dose distribution with high spatial resolution.Meanwhile,the similarity between the measured original data and the downsampled logfilebased reconstructed dose is regarded as the confidence of the reformatted dose distribution.Furthermore,we quantify the performance benefits of this new approach by directly comparing the reformatted dose distributions with 2D IC array detector mathematically interpolated measurements and original low-resolution measurements.The result shows that this new method is better than the mathematical interpolation and achieves gamma pass rates similar to those of the original low-resolution measurements.The reformatted dose distributions generally yield a confidence exceeding 95%. 展开更多
关键词 2D ion chamber array detectors Laplacian pyramid image blending High-resolution reformatted methods Pencil beam scanning Proton therapy
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ELECTRIC REGENERATION METHOD OF IONEXCHANGE RESIN IN THE MIXED BED 被引量:2
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作者 Wang Fang 《Chinese Journal of Reactive Polymers》 1998年第2期68-74,共7页
In this paper the self-regeneration process of the mixed resins consisting of cationand anion ion exchangers in the electrolialyser of the packed bed is analyzed and anelectric regeneration method is put forward to su... In this paper the self-regeneration process of the mixed resins consisting of cationand anion ion exchangers in the electrolialyser of the packed bed is analyzed and anelectric regeneration method is put forward to supply the desalinated water by mixedbed The electric regeneration technology is a new one used for regeneration of theexhausted ion exchangers in the mixed bed instead of the traditional regeneratingprocess by using acid and abc liquor Electric energy is consumed to regenerat theion exchangers loaded by salts from water treatment without any chemicals- acid alkali. The advantage of the electric regeneration process edibited convenientoperation, no discharge any waste, and therefore no Polluted to the recehang waterbode and the environmental ground 展开更多
关键词 Electric regeneration method of ion exchange resin Membranetechnology Pollution control
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A high-throughput screening method for breeding Aspergillus niger with 12C6+ ion beam-improved cellulase
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作者 Bo-Ling Jiang Shu-Yang Wang +7 位作者 Yu-Chen Wang Ji-Hong Chen Wen-Jian Li Jing Liu Wei Hu Guo-Qing Xiao Miao-Ying Dong Fu-Qiang Xu 《Nuclear Science and Techniques》 SCIE CAS CSCD 2017年第1期1-7,共7页
In this study,a high-throughput screening method was established through the 24-square deep-well microliter plate(MTP) fermentation and micro-plate detection for large-scale screening of the mutants.It was suitable fo... In this study,a high-throughput screening method was established through the 24-square deep-well microliter plate(MTP) fermentation and micro-plate detection for large-scale screening of the mutants.It was suitable for screening a large number of mutants and improving the breeding efficiency after heavy-ion beam irradiation.Seventeen strains showed higher cellulase activity compared with the initial strain after the screening of plate and MTP fermentation.The filter paper activity and β-glucosidase activity of Aspergillus niger H11201 had increased 38.74 and 63.23%separately compared with A.niger H11 by shaking flask fermentation,and it was genetically stable after being passaged to nine generations.The results indicate that the high-throughput screening method can be used for the quick breeding of A.niger with high cellulase activity. 展开更多
关键词 HIGH-THROUGHPUT screening method ASPERGILLUS NIGER H11 CELLULASE 12C6+ ion beam
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Fabrication of the Sodium Ions Extended Gate Field Effect Transistor by Using the Entrapment Method
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作者 Jung-Chuan Chou 《稀有金属材料与工程》 SCIE EI CAS CSCD 北大核心 2006年第A03期246-247,共2页
The sodium ion is necessary in physiological function and an important element in blood of human body,because the concentration of the sodium ion in the blood directly affects the functions of some organs or pathologi... The sodium ion is necessary in physiological function and an important element in blood of human body,because the concentration of the sodium ion in the blood directly affects the functions of some organs or pathological feature,how to detect it is an important affair.In this paper,we measure the concentration of sodium ions by the extended gate field effect transistor (EGFET).We use three different substrates RuO_x/p-Si,ITO glass,SnO_2/ITO to fabricate EGFET,and we choose the optimum structure.The fabrication of device needed to use the entrapment method. 展开更多
关键词 sodium ion extended gate field effect transistor(EGFET) entrapment method
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A general synthesis of inorganic nanotubes as high-rate anode materials of sodium ion batteries 被引量:1
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作者 Chunting Wang Ningyan Cheng +9 位作者 Zhongchao Bai Qinfen Gu Feier Niu Xun Xu Jialin Zhang Nana Wang Binghui Ge Jian Yang Yitai Qian Shixue Dou 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2023年第2期369-375,I0010,共8页
Ino rganic tubular materials have an exceptionally wide range of applications,yet developing a simple and universal method to controllably synthesize them remains challenging.In this work,we report a vaporphase-etchin... Ino rganic tubular materials have an exceptionally wide range of applications,yet developing a simple and universal method to controllably synthesize them remains challenging.In this work,we report a vaporphase-etching hard-template method that can directly fabricate tubes on various thermally stable oxide and sulfide materials.This synthesis method features the introduction of a vapor-phase-etching process to greatly simplify the steps involved in preparing tubular materials and avoids complicated postprocessing procedures.Furthermore,the in-situ heating transmission electron microscopy(TEM)technique is used to observe the dynamic formation process of TiO_(2-x) tubes,indicating that the removal process of the Sb2S3 templates first experienced the Rayleigh instability,then vapor-phase-etching process.When used as an anode for sodium ion batteries,the TiO_(2-x) tube exhibits excellent rate performance of134.6 mA h g^(-1) at the high current density of 10 A g^(-1) and long-term cycling over 7000 cycles.Moreover,the full cell demonstrates excellent cycling performance with capacity retention of 98%after 1000 cycles,indicating that it is a promising anode material for batteries.This method can be expanded to the design and synthesis of other thermally-stable tubular materials such as ZnS,MoS_(2),and SiO_(2). 展开更多
关键词 Tubular materials In-situ heating TEM Sodium ion batteries TiO_(2) Hard template methods
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A NEW METHOD FOR AROMATIZAT ION OF Δ^(5(10))-STEROIDAL C_(3)-DIMETHYL KETALS
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作者 Guang Dian HAN Hong Yan WEN 《Chinese Chemical Letters》 SCIE CAS CSCD 1993年第2期107-108,共2页
A new method for aromatization of Δ^(5(10))-steroidal C_3-dimethyl ketals with pyridinium hydrobromide perbromide (PHP.Py·HBr·Br_2) to aromatic A ring steroids in high yield (90-95%) is described.
关键词 ion STEROIDAL C3-DIMETHYL KETALS A NEW method FOR AROMATIZAT ion OF PHP
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Influence of polymer solution on the morphology and local structure of NH_(4)ZnPO_(4)powders synthesized by a simple precipitation method at room temperature
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作者 Santi Phumying Thongsuk Sichumsaeng +4 位作者 Pinit Kidkhunthod Narong Chanlek Jessada Khajonrit Somchai Sonsupap Santi Maensiri 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2022年第2期298-304,共7页
NH_(4)Zn PO_(4)powders were synthesized using a simple precipitation method at room temperature.The effects of polyvinyl pyrrolidone(PVP),polyvinyl alcohol(PVA),glucose,and hexadecyltrimethylammonium bromide(CTAB)solu... NH_(4)Zn PO_(4)powders were synthesized using a simple precipitation method at room temperature.The effects of polyvinyl pyrrolidone(PVP),polyvinyl alcohol(PVA),glucose,and hexadecyltrimethylammonium bromide(CTAB)solutions on the morphology and structure of the prepared samples were investigated.The phase composition and morphology of the prepared samples were characterized using X-ray diffraction and scanning electron microscopy,respectively.Depending on the polymer sources,the hexagonal structure prepared using non-surfactant of water completely changed to monoclinic structure when CTAB was added.X-ray absorption near-edge structure(XANES)and X-ray photoelectron spectroscopy(XPS)were performed to study the local structure and surface electronic structure of the prepared samples,confirming that the oxidation states of P and Zn ions are^(5+)and^(2+),respectively.On the basis of the results of inductively coupled plasma atomic emission spectroscopy(ICP-OES),the NH_(4)Zn PO_(4)powders can be classified as a slow-release fertilizer where less than 15%of the ions were released in 24 h.A simple precipitation method using water,PVP,PVA,sucrose,and CTAB as a template can be used to synthesize NH4 Zn PO4 powders.In addition,this method may be extended for the preparation of other oxide materials. 展开更多
关键词 ammonium zinc phosphate precipitation method MORPHOLOGY X-ray absorption spectroscopy ion release properties
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Novel Bilayer-Shelled N,O-Doped Hollow Porous Carbon Microspheres as High Performance Anode for Potassium-Ion Hybrid Capacitors 被引量:1
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作者 Zhen Pan Yong Qian +3 位作者 Yang Li Xiaoning Xie Ning Lin Yitai Qian 《Nano-Micro Letters》 SCIE EI CAS CSCD 2023年第9期423-435,共13页
With the advantages of high energy/power density,long cycling life and low cost,dual-carbon potassium ion hybrid capacitors(PIHCs)have great potential in the field of energy storage.Here,a novel bilayer-shelled N,O-do... With the advantages of high energy/power density,long cycling life and low cost,dual-carbon potassium ion hybrid capacitors(PIHCs)have great potential in the field of energy storage.Here,a novel bilayer-shelled N,O-doped hollow porous carbon microspheres(NOHPC)anode has been prepared by a self-template method,which is consisted of a dense thin shell and a hollow porous spherical core.Excitingly,the NOHPC anode possesses a high K-storage capacity of 325.9 mA h g^(−1)at 0.1 A g^(−1)and a capacity of 201.1 mAh g^(−1)at 5 A g^(−1)after 6000 cycles.In combination with ex situ characterizations and density functional theory calculations,the high reversible capacity has been demonstrated to be attributed to the co-doping of N/O heteroatoms and porous structure improved K+adsorption and intercalation capabilities,and the stable long-cycling performance originating from the bilayer-shelled hollow porous carbon sphere structure.Meanwhile,the hollow porous activated carbon microspheres(HPAC)cathode with a high specific surface area(1472.65 m^(2)g^(−1))deriving from etching NOHPC with KOH,contributing to a high electrochemical adsorption capacity of 71.2 mAh g^(−1)at 1 A g^(−1).Notably,the NOHPC//HPAC PIHC delivers a high energy density of 90.1 Wh kg^(−1)at a power density of 939.6 W kg^(−1)after 6000 consecutive charge-discharge cycles. 展开更多
关键词 Self-template method Bilayer-shelled hollow porous structure N O-doped carbon microspheres Dual-carbon potassium‐ion hybrid capacitor
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Synthesis of Low-cost LiFePO_4 from Li_2CO_3 by a Novel Hydrothermal Method and Investigation on the Reaction Mechanism 被引量:2
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作者 李向锋 HU Yunlong +1 位作者 LIU Fang 张昭 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2015年第2期223-230,共8页
Phspho-olivine Li Fe PO4 was synthesized from the relatively insoluble lithium source Li2CO3, proper iron and phosphorus sources(n(Li):n(Fe):n(P)=1:1:1) by a novel hydrothermal method. Afterwards, the opti... Phspho-olivine Li Fe PO4 was synthesized from the relatively insoluble lithium source Li2CO3, proper iron and phosphorus sources(n(Li):n(Fe):n(P)=1:1:1) by a novel hydrothermal method. Afterwards, the optimal sample was mixed with glucose and two-step calcinated(500 ℃ and 750 ℃) under high-purity N2 to obtain the Li Fe PO4/C composite. The resultant samples were characterized by X-ray diffraction(XRD), atomic absorption spectrometry(AAS), scanning electron microscops(SEM), transmission electron microscopy(TEM), energy dispersive spectrometry(EDS), elementary analysis(EA) and electrochemical tests. The results show that the optimal reaction condition is to set the reactant concentration at 0.5 mol·L^-1, the reaction temperature at 180 ℃ for 16 h duration. During the reaction course, an intermediate product NH4 Fe PO4·H2O was first synthesized, and then it reacted with Li+ to form Li Fe PO4. The optimized Li Fe PO4 sample with an average particle size(300 to 500 nm) and regular morphology exhibits a relatively high discharge capacity of 84.95 m Ah· g^-1 at the first charge-discharge cycle(0.1C, 1C=170 m A·g^-1). Moreover, the prepared Li Fe PO4/C composite shows a high discharge capacity of 154.3 m Ah·g^-1 at 0.1C and 128.2 m Ah·g^-1 even at 5C. Besides it has good reversibility and stability in CV test. 展开更多
关键词 Li-ion battery LiFePO4 hydrothermal method Li2CO3 reaction mechanism
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