The anode material Zn4SO4（OH）6·5H2O for nickle/zinc batteries was synthesized by hydrothermal method and was identified by XRD techniques. TG/DAT measurements reveal that the products lose lattice water at 145 ...The anode material Zn4SO4（OH）6·5H2O for nickle/zinc batteries was synthesized by hydrothermal method and was identified by XRD techniques. TG/DAT measurements reveal that the products lose lattice water at 145 ℃ and decompose to 3ZnO·ZnSO4 at 274 ℃. Cyclic voltammetry and recharging/discharging results show that CV curves have good symmetry, the ratio of oxidation area to reduction area for each curve is about 1, and the peak potential EPa and EPc have little change with the scanning rate. At 50th circle, more than 65% of theoretical capacity is obtained while at the same condition, zinc oxide electrode only remains 35% of theoretical capacity.展开更多
Low-temperature heat capacities of the solid compound Zn（C4H7O5）2（s） were measured in a temperature range from 78 to 374 K, with an automated adiabatic calorimeter. A solid-to-solid phase transition occurred in th...Low-temperature heat capacities of the solid compound Zn（C4H7O5）2（s） were measured in a temperature range from 78 to 374 K, with an automated adiabatic calorimeter. A solid-to-solid phase transition occurred in the temperature range of 295？322 K. The peak temperature, the enthalpy, and entropy of the phase transition were determined to be （316.269±1.039） K, （11.194±0.335） kJ？mol-1, and （35.391±0.654） J？K-1？mol-1, respectively. The experimental values of the molar heat capacities in the temperature regions of 78？295 K and 322？374 K were fitted to two polynomial equations of heat capacities（Cp,m） with reduced temperatures（X） and [X = f（T）], with the help of the least squares method, respectively. The smoothed molar heat capacities and thermodynamic functions of the compound, relative to that of the standard reference temperature 293.15 K, were calculated on the basis of the fitted polynomials and tabulated with an interval of 5 K. In addition, the possible mechanism of thermal decomposition of the compound was inferred by the result of TG-DTG analysis.展开更多
Series Bi3NbO7/Bi2Zn（2/3）Nb（4/3）O7 （BN/BZN） composites were synthesized through a facile solid state reaction method. The products were characterized by X-ray diffraction（XRD）, field emission scanning electron...Series Bi3NbO7/Bi2Zn（2/3）Nb（4/3）O7 （BN/BZN） composites were synthesized through a facile solid state reaction method. The products were characterized by X-ray diffraction（XRD）, field emission scanning electron microscopy（FE-SEM） and UV-vis diffuse reflectance spectroscopy（DRS）. When BN： BZN=0.1 mole ratio, the BN/BZN composite showed the best visible-light-driven photocatalytic performance, which decomposed nearly 100% of Rh B（10 ppm, p H=3-4） within 40 min. The results demonstrated that in-situ solid state synthesis of BN/BZN composites could be an efficient strategy to develop new photocatalyst for environmental remediation.展开更多
The development of promising zinc anodes mainly suffers from their low plating/stripping coulombic efficiencies when using aqueous electrolyte,which are mainly associated with the interfacial formation of irreversible...The development of promising zinc anodes mainly suffers from their low plating/stripping coulombic efficiencies when using aqueous electrolyte,which are mainly associated with the interfacial formation of irreversible by-products.It is urgent to develop technologies that can solve this issue fundamentally.Herein,we report an artificial Sc_(2)O_(3) protective film to construct a new class of interface for Zn anode.The density functional theory simulation and experimental results have proven that the interfacial side reaction was inhibited via a stratified adsorption effect between this artificial layer and Zn anode.Benefiting from this novel structure,the Sc_(2)O_(3)-coated Zn anode can run for more than 100 cycles without short circuit and exhibit low voltage hysteresis,and the coulombic efficiency increases by 1.2%.Importantly,it shows a good application prospect when matched with two of popular manganese-based and vanadium-based cathodes.The excellent electrochemical performance of the Sc_(2)O_(3)-coated Zn anode highlights the importance of rational design of anode materials and demonstrates a good way for developing high-performance Zn anodes with long lifespan and high efficiency.展开更多
Zinc(Zn) ferti-fortification using different sources and methods in Zn deficient soils is being advocated to increase Zn concentration in rice kernel as an alternative to pursuing greater Zn-use efficiency(ZnUE). A tw...Zinc(Zn) ferti-fortification using different sources and methods in Zn deficient soils is being advocated to increase Zn concentration in rice kernel as an alternative to pursuing greater Zn-use efficiency(ZnUE). A two-year field study was conducted to assess the effect of Zn application on Zn content and uptake at several growth stages and in several parts of the rice kernel: hull, bran, and the white rice kernel. Variety ‘PB 1509' with 1.25 kg Zn ha^(-1) as Zn-EDTA + 0.5% foliar spray(FS) at maximum tillering(MT) and panicle initiation(PI) stages registered the highest Zn content in hull, bran, and white rice kernel. Among parts of the rice kernel, Zn concentration decreased in the order hull > bran > white rice kernel,indicating that brown rice kernels are much denser in Zn content than polished rice.Considering the higher Zn accumulation in the bran, brown rice consumption, especially in Asia and Africa, could be recommended to overcome Zn malnutrition. The variety ‘PB 1401'showed the highest Zn uptake in rice straw, while ‘PB 1509' showed the highest Zn uptake in hull and white rice kernel. Application of 1.25 kg Zn ha^(-1)(Zn-EDTA) + 0.5% FS at MT and PI and 2.5 kg Zn ha^(-1) ZnSO_4·7H_2O(ZnSHH) + 0.5% FS at MT and PI resulted in higher Zn uptake than other treatments. On average, about one third of total Zn uptake remained in the white rice kernel, with the remaining two thirds accumulating in both hull and bran of brown rice. Zn-EDTA along with 0.5% FS, despite the application of a lower quantity of Zn leading to the highest Zn mobilization efficiency index(ZnMEI) and Zn-induced nitrogen recovery efficiency(ZniNRE), produced the highest kernel yield. However, of the two Zn sources, Zn-EDTA contributed more to the increase in ZnUE than did ZnSHH.展开更多
文摘The anode material Zn4SO4（OH）6·5H2O for nickle/zinc batteries was synthesized by hydrothermal method and was identified by XRD techniques. TG/DAT measurements reveal that the products lose lattice water at 145 ℃ and decompose to 3ZnO·ZnSO4 at 274 ℃. Cyclic voltammetry and recharging/discharging results show that CV curves have good symmetry, the ratio of oxidation area to reduction area for each curve is about 1, and the peak potential EPa and EPc have little change with the scanning rate. At 50th circle, more than 65% of theoretical capacity is obtained while at the same condition, zinc oxide electrode only remains 35% of theoretical capacity.
基金the National Natural Science Foundation of China(No.20673050).
文摘Low-temperature heat capacities of the solid compound Zn（C4H7O5）2（s） were measured in a temperature range from 78 to 374 K, with an automated adiabatic calorimeter. A solid-to-solid phase transition occurred in the temperature range of 295？322 K. The peak temperature, the enthalpy, and entropy of the phase transition were determined to be （316.269±1.039） K, （11.194±0.335） kJ？mol-1, and （35.391±0.654） J？K-1？mol-1, respectively. The experimental values of the molar heat capacities in the temperature regions of 78？295 K and 322？374 K were fitted to two polynomial equations of heat capacities（Cp,m） with reduced temperatures（X） and [X = f（T）], with the help of the least squares method, respectively. The smoothed molar heat capacities and thermodynamic functions of the compound, relative to that of the standard reference temperature 293.15 K, were calculated on the basis of the fitted polynomials and tabulated with an interval of 5 K. In addition, the possible mechanism of thermal decomposition of the compound was inferred by the result of TG-DTG analysis.
基金Funded by the National Natural Science Foundation of China(No.51662005)the Guangxi Natural Science Foundation(No.2014GXNSFFA118004)
文摘Series Bi3NbO7/Bi2Zn（2/3）Nb（4/3）O7 （BN/BZN） composites were synthesized through a facile solid state reaction method. The products were characterized by X-ray diffraction（XRD）, field emission scanning electron microscopy（FE-SEM） and UV-vis diffuse reflectance spectroscopy（DRS）. When BN： BZN=0.1 mole ratio, the BN/BZN composite showed the best visible-light-driven photocatalytic performance, which decomposed nearly 100% of Rh B（10 ppm, p H=3-4） within 40 min. The results demonstrated that in-situ solid state synthesis of BN/BZN composites could be an efficient strategy to develop new photocatalyst for environmental remediation.
基金supported by the National Natural Science Foundation of China(Grant no.51932011)。
文摘The development of promising zinc anodes mainly suffers from their low plating/stripping coulombic efficiencies when using aqueous electrolyte,which are mainly associated with the interfacial formation of irreversible by-products.It is urgent to develop technologies that can solve this issue fundamentally.Herein,we report an artificial Sc_(2)O_(3) protective film to construct a new class of interface for Zn anode.The density functional theory simulation and experimental results have proven that the interfacial side reaction was inhibited via a stratified adsorption effect between this artificial layer and Zn anode.Benefiting from this novel structure,the Sc_(2)O_(3)-coated Zn anode can run for more than 100 cycles without short circuit and exhibit low voltage hysteresis,and the coulombic efficiency increases by 1.2%.Importantly,it shows a good application prospect when matched with two of popular manganese-based and vanadium-based cathodes.The excellent electrochemical performance of the Sc_(2)O_(3)-coated Zn anode highlights the importance of rational design of anode materials and demonstrates a good way for developing high-performance Zn anodes with long lifespan and high efficiency.
基金the financial assistance received in the form of Senior Research Fellowship from the Director, ICAR-Indian Agricultural Research Institute, New Delhi, India, during his Doctor of Philosophy degree program
文摘Zinc(Zn) ferti-fortification using different sources and methods in Zn deficient soils is being advocated to increase Zn concentration in rice kernel as an alternative to pursuing greater Zn-use efficiency(ZnUE). A two-year field study was conducted to assess the effect of Zn application on Zn content and uptake at several growth stages and in several parts of the rice kernel: hull, bran, and the white rice kernel. Variety ‘PB 1509' with 1.25 kg Zn ha^(-1) as Zn-EDTA + 0.5% foliar spray(FS) at maximum tillering(MT) and panicle initiation(PI) stages registered the highest Zn content in hull, bran, and white rice kernel. Among parts of the rice kernel, Zn concentration decreased in the order hull > bran > white rice kernel,indicating that brown rice kernels are much denser in Zn content than polished rice.Considering the higher Zn accumulation in the bran, brown rice consumption, especially in Asia and Africa, could be recommended to overcome Zn malnutrition. The variety ‘PB 1401'showed the highest Zn uptake in rice straw, while ‘PB 1509' showed the highest Zn uptake in hull and white rice kernel. Application of 1.25 kg Zn ha^(-1)(Zn-EDTA) + 0.5% FS at MT and PI and 2.5 kg Zn ha^(-1) ZnSO_4·7H_2O(ZnSHH) + 0.5% FS at MT and PI resulted in higher Zn uptake than other treatments. On average, about one third of total Zn uptake remained in the white rice kernel, with the remaining two thirds accumulating in both hull and bran of brown rice. Zn-EDTA along with 0.5% FS, despite the application of a lower quantity of Zn leading to the highest Zn mobilization efficiency index(ZnMEI) and Zn-induced nitrogen recovery efficiency(ZniNRE), produced the highest kernel yield. However, of the two Zn sources, Zn-EDTA contributed more to the increase in ZnUE than did ZnSHH.
