In the investigation of the next-generation battery anode,Li metal has attracted increasing attention owing to its ultrahigh specific capacity and low reduction potential.However,its low columbic efficiency,limited cy...In the investigation of the next-generation battery anode,Li metal has attracted increasing attention owing to its ultrahigh specific capacity and low reduction potential.However,its low columbic efficiency,limited cycling life,and serious safety hazards have hindered the practical application of rechargeable Li metal batteries.Although several strategies have been proposed to enhance the electrochemical performance of Li metal anodes,most are centered around ether-based electrolytes,which are volatile and do not provide a sufficiently large voltage window.Therefore,we aimed to attain stable Li deposition/stripping in a commercial carbonate-based electrolyte.Herein,we have successfully synthesized hydrogen titanate(HTO)nanowire arrays decorated with homogenous Ag nanoparticles(NPs)(Ag@HTO)via simple hydrothermal and silver mirror reactions.The 3 D cross-linked array structure with Ag NPs provides preferable nucleation sites for uniform Li deposition,and most importantly,when assembled with the commercial LiNi_(0.5)Co0.2Mn_(0.3)O_(2) cathode material,the Ag@HTO could maintain a capacity retention ratio of 81.2% at 1 C after 200 cycles,however the pristine Ti foil failed to do so after only 60 cycles.Our research therefore reveals a new way of designing current collectors paired with commercial high voltage cathodes that can create high energy density Li metal batteries.展开更多
The formation of calcium titanate in the carbothermic reduction of vanadium titanomagnetite concentrate(VTC)by adding CaCO3 was investigated.Thermodynamic analysis was employed to show the feasibility of calcium titan...The formation of calcium titanate in the carbothermic reduction of vanadium titanomagnetite concentrate(VTC)by adding CaCO3 was investigated.Thermodynamic analysis was employed to show the feasibility of calcium titanate formation by the reaction of ilmenite and Ca CO3 in a reductive atmosphere,where ilmenite is more easily reduced by CO or carbon in the presence of CaCO3.The effects of CaCO3 dosage and reduction temperature on the phase transformation and metallization degree were also investigated in an actual roasting test.Appropriate increase of CaCO3 dosages and reduction temperatures were found to be conducive to the formation of calcium titanate,and the optimum conditions were a CaCO3 dosage of 18 wt%and a reduction temperature of 1400°C.Additionally,scanning electron microscopy–energy dispersive spectrometry(SEM–EDS)analysis shows that calcium titanate produced via the carbothermic reduction of VTC by CaCO3 addition was of higher purity with particle size approximately 50μm.Hence,the separation of calcium titanate and metallic iron will be the focus in the future study.展开更多
In a pH 2.4 Britton-Robinson buffer medium, the anthracycline antibiotics mitoxantrone（MXT） could react with metal ions such as Pd（Ⅱ）, Co（Ⅱ） and Cu（Ⅱ） to form 1：2（molar ratio） cationic chelates, which fu...In a pH 2.4 Britton-Robinson buffer medium, the anthracycline antibiotics mitoxantrone（MXT） could react with metal ions such as Pd（Ⅱ）, Co（Ⅱ） and Cu（Ⅱ） to form 1：2（molar ratio） cationic chelates, which further reacted with the anionic dye titan yellow to form 1：2 ternary ion-association complexes by electrostatic interaction. As a result, the intensity of resonance Rayleigh scattering（RRS） was enhanced greatly. These RRS spectral characteristics of various metal ion systems were similar, and the maximum RRS wavelengths were all located at 454 nm. But the increments of RRS intensities were different in the series of Pd（Ⅱ）〉Co（Ⅱ）〉Cu（Ⅱ）. The enhanced RRS intensities were proportional to the concentration of MXT in a range of 0.03-2.4μg/mL and the detection limit（3σ） was 0.009μg/mL for the Pd（Ⅱ） system. In this study, the optimum conditions of the reactions and the effects of foreign substances were investigated, in addition, the composition and reaction mechanism of ion-association complexes were discussed. Thus a highly sensitive, simple and rapid method is proposed for the determination of MXT in urine and serum samples.展开更多
The behaviors of lead zirconate titanate （PZT） deposited as the dielectric for high-voltage devices are investigated experimentally and theoretically. The devices demonstrate not only high breakdown voltages above 3...The behaviors of lead zirconate titanate （PZT） deposited as the dielectric for high-voltage devices are investigated experimentally and theoretically. The devices demonstrate not only high breakdown voltages above 350 V, but also excellent memory behaviors. A drain current–gate voltage （ID-VG） memory window of about 2.2 V is obtained at the sweep voltages of ±10 V for the 350-V laterally diffused metal oxide semiconductor （LDMOS）. The retention time of about 270 s is recorded for the LDMOS through a controlled ID-VG measurement. The LDMOS with memory behaviors has potential to be applied in future power conversion circuits to boost the performance of the energy conversion system.展开更多
PR0CESS：TITAN Metal Fabricators公司成矗于1998年，这些年的发展经过了哪几个阶段？Steven Muscarella：TITIAN Metal Fabricators的产品可以追溯到1970年，公司前身是由我的父亲创立的一个化工设备公司，1996年父亲把公司卖给了当...PR0CESS：TITAN Metal Fabricators公司成矗于1998年，这些年的发展经过了哪几个阶段？Steven Muscarella：TITIAN Metal Fabricators的产品可以追溯到1970年，公司前身是由我的父亲创立的一个化工设备公司，1996年父亲把公司卖给了当时同样做化工设备的公司。1998年，我和我的兄弟创立了现在的TITAN Metal Fabricators公司，技术和工艺都集成了父亲创建的公司。公司目前的一些经验丰富的技术、销售、服务人员都是公司创立之初的员工。展开更多
基金supported by the National Natural Science Foundation of China(Nos.2127318,21621091,and 21875195)the National Key Research and Development Program of China(No.2017YFB0102000)the Fundamental Research Funds for the Central Universities(No.20720190040)。
文摘In the investigation of the next-generation battery anode,Li metal has attracted increasing attention owing to its ultrahigh specific capacity and low reduction potential.However,its low columbic efficiency,limited cycling life,and serious safety hazards have hindered the practical application of rechargeable Li metal batteries.Although several strategies have been proposed to enhance the electrochemical performance of Li metal anodes,most are centered around ether-based electrolytes,which are volatile and do not provide a sufficiently large voltage window.Therefore,we aimed to attain stable Li deposition/stripping in a commercial carbonate-based electrolyte.Herein,we have successfully synthesized hydrogen titanate(HTO)nanowire arrays decorated with homogenous Ag nanoparticles(NPs)(Ag@HTO)via simple hydrothermal and silver mirror reactions.The 3 D cross-linked array structure with Ag NPs provides preferable nucleation sites for uniform Li deposition,and most importantly,when assembled with the commercial LiNi_(0.5)Co0.2Mn_(0.3)O_(2) cathode material,the Ag@HTO could maintain a capacity retention ratio of 81.2% at 1 C after 200 cycles,however the pristine Ti foil failed to do so after only 60 cycles.Our research therefore reveals a new way of designing current collectors paired with commercial high voltage cathodes that can create high energy density Li metal batteries.
基金the National Natural Science Foundation of China(No.51674018)。
文摘The formation of calcium titanate in the carbothermic reduction of vanadium titanomagnetite concentrate(VTC)by adding CaCO3 was investigated.Thermodynamic analysis was employed to show the feasibility of calcium titanate formation by the reaction of ilmenite and Ca CO3 in a reductive atmosphere,where ilmenite is more easily reduced by CO or carbon in the presence of CaCO3.The effects of CaCO3 dosage and reduction temperature on the phase transformation and metallization degree were also investigated in an actual roasting test.Appropriate increase of CaCO3 dosages and reduction temperatures were found to be conducive to the formation of calcium titanate,and the optimum conditions were a CaCO3 dosage of 18 wt%and a reduction temperature of 1400°C.Additionally,scanning electron microscopy–energy dispersive spectrometry(SEM–EDS)analysis shows that calcium titanate produced via the carbothermic reduction of VTC by CaCO3 addition was of higher purity with particle size approximately 50μm.Hence,the separation of calcium titanate and metallic iron will be the focus in the future study.
基金Supported by Education Committee of Chongqing City, China(No.KJ081306)
文摘In a pH 2.4 Britton-Robinson buffer medium, the anthracycline antibiotics mitoxantrone（MXT） could react with metal ions such as Pd（Ⅱ）, Co（Ⅱ） and Cu（Ⅱ） to form 1：2（molar ratio） cationic chelates, which further reacted with the anionic dye titan yellow to form 1：2 ternary ion-association complexes by electrostatic interaction. As a result, the intensity of resonance Rayleigh scattering（RRS） was enhanced greatly. These RRS spectral characteristics of various metal ion systems were similar, and the maximum RRS wavelengths were all located at 454 nm. But the increments of RRS intensities were different in the series of Pd（Ⅱ）〉Co（Ⅱ）〉Cu（Ⅱ）. The enhanced RRS intensities were proportional to the concentration of MXT in a range of 0.03-2.4μg/mL and the detection limit（3σ） was 0.009μg/mL for the Pd（Ⅱ） system. In this study, the optimum conditions of the reactions and the effects of foreign substances were investigated, in addition, the composition and reaction mechanism of ion-association complexes were discussed. Thus a highly sensitive, simple and rapid method is proposed for the determination of MXT in urine and serum samples.
基金the National Basic Research Program of China(Grant No.50772019)the National Natural Science Foundation of China(Grant No.61204084)
文摘The behaviors of lead zirconate titanate （PZT） deposited as the dielectric for high-voltage devices are investigated experimentally and theoretically. The devices demonstrate not only high breakdown voltages above 350 V, but also excellent memory behaviors. A drain current–gate voltage （ID-VG） memory window of about 2.2 V is obtained at the sweep voltages of ±10 V for the 350-V laterally diffused metal oxide semiconductor （LDMOS）. The retention time of about 270 s is recorded for the LDMOS through a controlled ID-VG measurement. The LDMOS with memory behaviors has potential to be applied in future power conversion circuits to boost the performance of the energy conversion system.
文摘PR0CESS：TITAN Metal Fabricators公司成矗于1998年，这些年的发展经过了哪几个阶段？Steven Muscarella：TITIAN Metal Fabricators的产品可以追溯到1970年，公司前身是由我的父亲创立的一个化工设备公司，1996年父亲把公司卖给了当时同样做化工设备的公司。1998年，我和我的兄弟创立了现在的TITAN Metal Fabricators公司，技术和工艺都集成了父亲创建的公司。公司目前的一些经验丰富的技术、销售、服务人员都是公司创立之初的员工。
