FeCoxNiCuAl （x values in molar ratio, x=0.2, 0.5, 1, 1.5, 2 and 3） alloys were pre- pared using a suck-casting method. The effect of Co element on phase constituents, microstructure and mechanical properties of the ...FeCoxNiCuAl （x values in molar ratio, x=0.2, 0.5, 1, 1.5, 2 and 3） alloys were pre- pared using a suck-casting method. The effect of Co element on phase constituents, microstructure and mechanical properties of the FeCox NiCuA1 alloys was investigated using X-ray diffraction, scanning electron microscopy, optical microscopy and com- pressive tests. It was found that the Co addition has a significant influence on the structure and properties of the FeCo^NiCuA1 alloys. The alloys have typical den- drite microstructure, and are composed of a simple fcc structure and bcc structure. The addition of Co promotes the formation of fcc phase in the alloys, retards the compressive strength and hardness of the alloys, and enhances the plasticity of the alloys.展开更多
A detailed study on a small scale of the effect of phosphatization on the chemistry of marine cobalt-rich ferromanganese crusts supplies useful information for the evaluation and comprehensive utilization of crust min...A detailed study on a small scale of the effect of phosphatization on the chemistry of marine cobalt-rich ferromanganese crusts supplies useful information for the evaluation and comprehensive utilization of crust mineral resources. Sub-samples from top to bottom of a 10-cm thick sample from the NW Pacific Magellan seamount were taken at 5 mm intervals. The concentration profiles of ore-forming and rare earth elements show that obvious differences exist between young unphosphatized crusts and old phosphatized crusts. In the old crusts Fe, Mn, Si, Al, Zn, Mg, Co, Ni and Cu elements are depleted and Ca, P, Sr, Ba and Pb elements are enriched. The order of depletion is Co > Ni > Mg > Al > Mn > Si> Cu > Zn > Fe, while the order of enrichment is P > Ca > Ba > Pb > Sr. The phosphate mineral controls the concentration variation of the ore-forming elements in crusts and causes loss of the main ore-forming elements such as Co and Ni. The phosphatization also affects the abundance of REEs in the crusts. REEs are more abundant and the content of Ce in old crusts is higher than that in young crusts, however, the pattern of REEs and their fractionation characteristics in new and old crusts are not fundamentally changed. A Y-positive anomaly in old crusts has no relationship to the phosphatization.展开更多
Let (H, R) be a co-Frobenius quasitriangular Hopf algebra with antipode S. Denote the set of group-like elements in H by G (H). In this paper, we find a necessary and sufficient condition for (H, R) to have a ribbon e...Let (H, R) be a co-Frobenius quasitriangular Hopf algebra with antipode S. Denote the set of group-like elements in H by G (H). In this paper, we find a necessary and sufficient condition for (H, R) to have a ribbon element. The condition gives a connection with the order of G (H) and the order of S2.展开更多
Element geochemistry of lake sediments has been widely used to detect climate change because element composition and ratios can reflect the weathering degree in the source area. Given the element composition of lake s...Element geochemistry of lake sediments has been widely used to detect climate change because element composition and ratios can reflect the weathering degree in the source area. Given the element composition of lake sediments from Gulug Co Lake, Hoh Xil, Qinghai-Xizang Plateau, chemical index of alteration (CIA), index of composition variability (ICV) and other element ratios have been used to establish the weathering sequence of this area since 1820 AD. The weathering is so weak that the element composition change is more sensitive to climate change and autochthonous processes. From 1820 to 1984 AD, there were two drier periods with a wetter interval from 1870 to 1945 AD. After 1984 the weather showed a tendency of becoming wet.展开更多
Composite nickel hydroxide films were prepared by cathodic co electrodeposition from metal nitrate solution and characterized by cyclic voltammetry in 1.0 mol/L KOH solution. The codeposited light rare earth elements...Composite nickel hydroxide films were prepared by cathodic co electrodeposition from metal nitrate solution and characterized by cyclic voltammetry in 1.0 mol/L KOH solution. The codeposited light rare earth elements were lanthanum, cerium, praseodymium and neodymium. The films were analyzed by spectrophotometry and optical transmission. The results of the cyclic voltammetry in 1.0 mol/L KOH solution showed that the current density for oxygen evolution at the film electrode was affected by the co deposited rare earth metal ions in the film. About 20 mA/cm 2 increase of current density for oxygen evolution was found when the film was obtained from the solution with cerium (7% v/v) and nickel (93% v/v) nitrate. The effects of galvanostatic cathodic current density for the film formation on the oxygen evolution at the film electrodes from the alkaline were discussed.展开更多
Along with the continuous consumption in lithium-ion batteries (LIBs), the price of cobalt is inevitably going up in recent years. Therefore, recycling valuable Co element from spent devices, and boosting its service ...Along with the continuous consumption in lithium-ion batteries (LIBs), the price of cobalt is inevitably going up in recent years. Therefore, recycling valuable Co element from spent devices, and boosting its service efficiency are becoming two indispensable approaches to promote the utilization of Co in various energy conversion/storage devices. Herein, we realize the recovery of Co from spent LIBs and synthesize a three–dimensional (3D) sea-urchin-like cobalt nitride composite material (labeled as CoN-Gr-2), which is used as a bi-functional catalyst for water splitting. Benefiting from the intrinsic high conductivity, larger surface area and unique 3D sea–urchin–like architecture, CoN-Gr-2 shows an excellent electron transfer efficiency, highly exposed active sites as well as the superior mass transport capacity. The CoN-Gr-2 catalyst exhibits low overpotentials of 128.9 mV and 280 mV for hydrogen evolution reaction (HER) and oxygen evolution reaction (OER), which are comparable to the commercial 20 wt% Pt/C and RuO_(2) catalysts. Moreover, when adopting CoN-Gr-2 as both anode and cathode materials for overall water splitting (in 1.0 M KOH electrolyte), the assembled cell achieves a current density of 10 mA cm^(−2) at 1.61 V, which almost close to that of Pt/C||RuO_(2) benchmark (1.60 V), demonstrating its superior water-splitting efficiency. Meanwhile, the CoN catalysts exhibit strong chemical interaction with the Gr support, suppressing the aggregation of CoN catalysts and maintains their high activity during HER and OER reactions. So, the cell exhibits a high current retention of 97.3% after 40 h. This work successfully develops an industrial chain from recycling Co wastes in spent energy devices to controllably designing 3D sea-urchin-like CoN-Gr with high water splitting efficiency. Therefore, it could further promote the efficient utilization of valuable Co element in various energy devices.展开更多
基金supported by the National Natural Science Foundation of China (Grant No.51171041)the Fundamental Research Funds for the Central University (Grant No.N100409001)
文摘FeCoxNiCuAl （x values in molar ratio, x=0.2, 0.5, 1, 1.5, 2 and 3） alloys were pre- pared using a suck-casting method. The effect of Co element on phase constituents, microstructure and mechanical properties of the FeCox NiCuA1 alloys was investigated using X-ray diffraction, scanning electron microscopy, optical microscopy and com- pressive tests. It was found that the Co addition has a significant influence on the structure and properties of the FeCo^NiCuA1 alloys. The alloys have typical den- drite microstructure, and are composed of a simple fcc structure and bcc structure. The addition of Co promotes the formation of fcc phase in the alloys, retards the compressive strength and hardness of the alloys, and enhances the plasticity of the alloys.
基金supported by grant DY95-08-05 from the China Ocean Mineral Resources R&D Associationthe National Natural Science Foundation of China(Grant 40373002).
文摘A detailed study on a small scale of the effect of phosphatization on the chemistry of marine cobalt-rich ferromanganese crusts supplies useful information for the evaluation and comprehensive utilization of crust mineral resources. Sub-samples from top to bottom of a 10-cm thick sample from the NW Pacific Magellan seamount were taken at 5 mm intervals. The concentration profiles of ore-forming and rare earth elements show that obvious differences exist between young unphosphatized crusts and old phosphatized crusts. In the old crusts Fe, Mn, Si, Al, Zn, Mg, Co, Ni and Cu elements are depleted and Ca, P, Sr, Ba and Pb elements are enriched. The order of depletion is Co > Ni > Mg > Al > Mn > Si> Cu > Zn > Fe, while the order of enrichment is P > Ca > Ba > Pb > Sr. The phosphate mineral controls the concentration variation of the ore-forming elements in crusts and causes loss of the main ore-forming elements such as Co and Ni. The phosphatization also affects the abundance of REEs in the crusts. REEs are more abundant and the content of Ce in old crusts is higher than that in young crusts, however, the pattern of REEs and their fractionation characteristics in new and old crusts are not fundamentally changed. A Y-positive anomaly in old crusts has no relationship to the phosphatization.
文摘Let (H, R) be a co-Frobenius quasitriangular Hopf algebra with antipode S. Denote the set of group-like elements in H by G (H). In this paper, we find a necessary and sufficient condition for (H, R) to have a ribbon element. The condition gives a connection with the order of G (H) and the order of S2.
文摘Element geochemistry of lake sediments has been widely used to detect climate change because element composition and ratios can reflect the weathering degree in the source area. Given the element composition of lake sediments from Gulug Co Lake, Hoh Xil, Qinghai-Xizang Plateau, chemical index of alteration (CIA), index of composition variability (ICV) and other element ratios have been used to establish the weathering sequence of this area since 1820 AD. The weathering is so weak that the element composition change is more sensitive to climate change and autochthonous processes. From 1820 to 1984 AD, there were two drier periods with a wetter interval from 1870 to 1945 AD. After 1984 the weather showed a tendency of becoming wet.
文摘Composite nickel hydroxide films were prepared by cathodic co electrodeposition from metal nitrate solution and characterized by cyclic voltammetry in 1.0 mol/L KOH solution. The codeposited light rare earth elements were lanthanum, cerium, praseodymium and neodymium. The films were analyzed by spectrophotometry and optical transmission. The results of the cyclic voltammetry in 1.0 mol/L KOH solution showed that the current density for oxygen evolution at the film electrode was affected by the co deposited rare earth metal ions in the film. About 20 mA/cm 2 increase of current density for oxygen evolution was found when the film was obtained from the solution with cerium (7% v/v) and nickel (93% v/v) nitrate. The effects of galvanostatic cathodic current density for the film formation on the oxygen evolution at the film electrodes from the alkaline were discussed.
基金The authors would like to acknowledge financial support provided by the Key National Natural Science Foundation of Yunnan Province(No.2018FA028,NO.2019FD039 and No.2019FY003023)the National Natural Science Foundation of China(No.51474191,No.52064049 and No.21467030)+4 种基金the National Natural Science Foundation of Yunnan Provincial Department of Education(No.2020 J0016)the International Joint Research Center for Advanced Energy Materials of Yunnan Province(202003AE140001)the Key Laboratory of Solid State Ions for Green Energy of Yunnan University(2019)the Postdoctoral Foundation of Department of Human Resources and Social Security of Yunnan Province(No.W8163007)the Program for Outstand Young Talents(2018)of Yunnan University.
文摘Along with the continuous consumption in lithium-ion batteries (LIBs), the price of cobalt is inevitably going up in recent years. Therefore, recycling valuable Co element from spent devices, and boosting its service efficiency are becoming two indispensable approaches to promote the utilization of Co in various energy conversion/storage devices. Herein, we realize the recovery of Co from spent LIBs and synthesize a three–dimensional (3D) sea-urchin-like cobalt nitride composite material (labeled as CoN-Gr-2), which is used as a bi-functional catalyst for water splitting. Benefiting from the intrinsic high conductivity, larger surface area and unique 3D sea–urchin–like architecture, CoN-Gr-2 shows an excellent electron transfer efficiency, highly exposed active sites as well as the superior mass transport capacity. The CoN-Gr-2 catalyst exhibits low overpotentials of 128.9 mV and 280 mV for hydrogen evolution reaction (HER) and oxygen evolution reaction (OER), which are comparable to the commercial 20 wt% Pt/C and RuO_(2) catalysts. Moreover, when adopting CoN-Gr-2 as both anode and cathode materials for overall water splitting (in 1.0 M KOH electrolyte), the assembled cell achieves a current density of 10 mA cm^(−2) at 1.61 V, which almost close to that of Pt/C||RuO_(2) benchmark (1.60 V), demonstrating its superior water-splitting efficiency. Meanwhile, the CoN catalysts exhibit strong chemical interaction with the Gr support, suppressing the aggregation of CoN catalysts and maintains their high activity during HER and OER reactions. So, the cell exhibits a high current retention of 97.3% after 40 h. This work successfully develops an industrial chain from recycling Co wastes in spent energy devices to controllably designing 3D sea-urchin-like CoN-Gr with high water splitting efficiency. Therefore, it could further promote the efficient utilization of valuable Co element in various energy devices.
