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Copyright of Nonferrous Metals (Extractive Metallurgy) is the property of Beijing Research Institute of Mining & Metallurgy Technology Group and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Nonferrous Metals (Extractive Metallurgy) is the property of Beijing Research Institute of Mining & Metallurgy Technology Group and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of China Pulp & Paper is the property of China Pulp & Paper Magazines Publisher and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

In the context of "dual carbon", the aluminum smelling industry is facing enormous pressure to reduce emissions. This paper takes an electrolytic aluminum enterprise n Shanxi province as an example to calculate the carbon emissions of each ink of the enterprise in 2021 and identify the mam factors that affect the carbon emission reduction of the electrolytic aluminum industry. Using scenario analysis method to predict the adjustment of power structure, upgrading of low-carbon electrolytic aluminum technology, and application of recycled aluminum in Shanxi province from 2021 to 2030. Establish a multi factor analysis model for electrolytic aluminum carbon emissions, and explore the impact of various control variables on reducing carbon emissions per ton of aluminum for enterprises in benchmark and policy scenarios. The results show that changes in the power structure have the greatest contribution to the greenhouse gas emissions reduction of the enterprise, with emissions reductions accounting for 31. 63% of the total emissions under the 2030 baseline scenario and 40. 66% of the total emissions under the policy scenario; When coupled with changes in power structure and the proportion of recycled aluminum, the emission reduction effect Is most significant, with the emission reduction accounting for 67.82% of the total emissions in the 2030 policy scenario; Under the three coupling situation, the carbon emissions of the enterprise gradually tend to zero. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Dalian University of Technology / Dalian Ligong Daxue Xuebao is the property of Journal of Dalian University of Technology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The electrochemical behavior of Li2O in KCl-LiCl molten salt has been studied by cyclic voltammetry and chronopotentiometry. The diffusion coefficient D=0.5×10-5 cm2/s of O2- in KCl-LiCl molten salt at 923 K has been calculated by convolutional voltammetry. Gd2O3, Nd2O3, Sm2O3 and Dy2O3 were used as cathodes to conduct electrolysis in KCl-LiCl-Li2O(w=1%) molten salt(constant voltage 3.40 V, electrolysis temperature 923 K, electrolysis time 25 h). By XRD analysis, it was confirmed that the rare earth oxides are partially reduced to metals, and the possible reactions during the electrolysis process were analyzed. At the same time, the PRS model was used to analyze the electrolytic reduction models of these rare earth oxides, and the optimal porosity(Popt) of Gd2O3, Nd2O3, Sm2O3 and Dy2O3 are 18.7%, 24.2%, 30.6%,16.7%, respectively. The minimum electrolysis time of them are 133, 157, 143, and 119 h, respectively, which are compared with the results of the electrolytic experiment, it is found that the porosity and electrolysis time of the cathode do not meet the requirements for complete reduction of metal oxides, and the corresponding explanation is given.

Organic electrosynthesis is an emerging field of organic synthesis because its controllability, efficiency, and "green" profile. However, electrochemical synthesis has not yet been implemented in the organic chemistry laboratory curriculum for undergraduates. Organic sulfides are widely present in natural products and bioactive molecules. They are also important intermediates in organic synthesis. Most traditional methods for the preparation of these species require reductants and harsh reaction conditions. Recently, we reported the facile electrochemical reduction of sulfoxides to sulfides under mild reaction conditions. Subsequently, we designed a "green" electrochemical protocol for the efficient synthesis of diphenyl sulfide, from readily available phenyl sulfoxide, at room temperature. This experiment aimed to establish the concept of "green" synthesis amongst the undergraduate student population. [ABSTRACT FROM AUTHOR]

Against issues of the high overpotential, low conversion efficiency, and poor product selectivity of electrochemical CO2 reduction (CO2ER), the research progress of electrocatalysts, electrolytes, and electrolytic cells were reviewed. It was found that the currently developed electrocatalysts contained metal nanoparticles, metal alloy, metal oxides, metal sulfide and single metal atoms. Their catalytic activity, selectivity and stability could be enhanced by adjusting the structure and particle size of electrocatalysts, doping additional elements or introducing structural defects. The electrolyte of CO2ER included aqueous electrolyte, ionic liquid electrolyte and organic electrolyte. At present, the aqueous electrolyte was widely applied, but its selectivity was inhibited by the side hydro- gen evolution reaction. The ionic liquid electrolyte and organic electrolyte has high solubility of CO2 and could restrain the hydrogen evolution reaction, which was considered as the main application research direction in the future. The CO2ER can be conducted in H-type cell, continuous flow cell and MEA reactors, among which MEA is one of the important technology to realize the scale application of electrochemical CO2 conversion. In the future, the reaction mechanism should be further studied, and the active sites should be probed to realize the precise control of catalytic performance and stability. Meanwhile, the novel electrolytes should be developed and the design of electrolytic cell should be modified in order to further improve the catalytic performance. [ABSTRACT FROM AUTHOR]

LaNi5 alloy were prepared via electro deoxidizing oxide precursors in molten KCl LiCl at 650 °C. In this study, chemical composition and phase compositions of electrolysis intermediate products were examined to determine the reduction mechanism. The results show that NiO is reduced firstly and lanthanum oxide in LaNiOx is reduced to lanthanum metal and alloyed with nickel to form the alloy LaNi5. In the process of oxidizing metal oxides, LaNiOx is produced as an intermediate product, which is further reduced and alloyed with the previously reduced nickel to generate LaNi5. [ABSTRACT FROM AUTHOR]

Copyright of Journal of South China Normal University (Natural Science Edition) / Huanan Shifan Daxue Xuebao (Ziran Kexue Ban) is the property of Journal of South China Normal University (Natural Science Edition) Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The objective of this study was to develop an efficient non-enzymatic electrochemical sensor for H2O2 detection in milk using the catalytic reduction of H2O2 on ZnFeCoO4. Firstly, ZnFeCoO4 derived from ZnCo2O4 by the partial substitution of Co with Fe was synthesized via sol-gel combustion. In ZnCo2O4, 1 mmol Zn(NO3)2·6H2O and 2 mmol of Co(NO3)2·6H2O were dissolved in a nitric acid solution (2mL of nitric acid, and 30ml of distilled water). The sticky gel was subsequently obtained by adding 15 mmol citric acid and stirring for 5 h in the oil bath at 90℃. After that, the gel was placed in a 170℃ oven (10℃/min heating rate) for 12 hours. Then, the moisture-removed gel was crushed with a mortar. Finally, the powder was calcined in a 600 ℃ tubular furnace (5℃/min heating rate) for 6 hours to obtain the spinel phase ZnCo2O4 powder. The preparation process of ZnFeCoO4 was consistent with that of ZnCo2O4. The only difference was that the 2 mmol of Co (NO3)2·6H2O was replaced with 2 mmol of Fe(NO3)2·6H2O. Transmission electron microscopy, X-ray diffraction, and X-ray photoelectron spectroscopy were used to characterize the crystal structure and morphology of the catalyst, while cyclic voltammetry (CV) was used to study the electrochemical performance of the electrode. In order to verify the effectiveness of the ZnFeCoO4 electrode in detecting H2O2 content in milk, the milk from the local supermarket was centrifuged and 1 mL supernatant was dissolved in 10 mL PBS (pH 7.4). Standard addition was used for the recovery experiment. The results showed that a similar morphology was obtained after the partial or complete replacement of Co with Fe. ZnFeCoO4 presented a better crystal shape and high consistency with the standard database card JCPDS No.23-1390. The mass ratios of Zn, Co, and Fe were measured as 31.46%, 35.77%, and 27.15%, respectively, and the molar ratio was about 1:1.2:1, which roughly met the chemical expression of the compound. The XRD patterns of ZnCo2O4 and ZnFeCoO4 showed that the diffraction peaks of ZnFeCoO4 were basically the same as those of ZnCo2O4, both of which were conformed to the standard database card JCPDS No.23-1390, indicating the spinel phases. In addition, the diffraction peak of ZnFeCoO4 was shifted to a smaller angle than that of ZnCo2O4, because the lattice radius of Fe3+ was slightly larger than that of Co3+. This proved the successful synthesis of spinel phase ZnFeCoO4. The CV analysis showed that the ZnFeCoO4 presented better catalytic activity than the ZnCo2O4, where the electrochemical sensor using ZnFeCoO4 shared the better electrocatalytic performance for H2O2 with a theoretical detection limit of 0.5 μmol/L. There was a linear relationship between the concentration of hydrogen peroxide and the peak reduction current in the range of 0.5-2.5 mmol/L, where the determination coefficient (R²) is 0.989. The stability and selectivity of ZnFeCoO4 electrode analysis showed that there was no significant change in the current density when the electrode was exposed to 1mM H2O2 solution for 30 days. After one month, the observed current density was about 92.7% of the original current density, with a relative standard deviation of 13.2%, indicating the better stability of the ZnFeCoO4 electrode. The amperage method was implemented to evaluate the effect of ascorbic acid, glucose, sucrose, citric acid, urea, and H2O2 on the current density response. Except for H2O2, there was no significant change in the current density, indicating the better selectivity of the sensor. In addition, the sensor also presented excellent reproducibility for H2O2. Excellent recoveries from 98.60% to 101.23% were obtained for the H2O2-spiked milk. The as-presented sensor can be expected to serve as a promising candidate for the H2O2 determination in food safety. [ABSTRACT FROM AUTHOR]

Copyright of Environmental Science & Technology (10036504) is the property of Editorial Board of Environmental Science & Technology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The greenhouse effect caused by the continuous increase of carbon dioxide concentration has caused a series of ecological and environmental problems such as extreme weather and melting of glaciers around the world. In order to reduce carbon dioxide content and improve the adverse impact of climate warming，it is urgent to develop efficient，green and safe processing technologies and promote the sustainable development of carbon resource cycle. Molten salt ionic liquid，as a good electrochemical conversion medium，provides a promising technical route for carbon dioxide reduction. The research on the capture and electrochemical reduction of carbon dioxide in high-temperature molten salt at home and abroad in recent years is reviewed，and the electrochemical and thermodynamic mechanisms of molten salt electrodeposited carbon are briefly described. The preparation of high value-added carbon materials with different morphologies： amorphous carbon，carbon spheres and carbon nanotubes are summarized，and finally the future development direction is prospected. [ABSTRACT FROM AUTHOR]

Copyright of Precious Metals / Guijinshu is the property of Precious Metals Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The substantial increase of CO2 concentration in the atmosphere has led to serious environmental problems, and electrochemical reduction of CO2 is an effective method to slow down CO2 concentration. After Ti electrode was modified by oxalic acid etching and was heat treated. The original smooth microscopic surface of Ti electrode became depressions and holes. It greatly increased the microscopic surface area and the reaction activity to electrochemical reduction CO2.When Ti electrode modified by oxalic acid was used as cathode in CO2electrochemical reduction in 0.5 mol/L KHCO3 solution, the Faraday efficiency of methanol product was up to 45.83% as the electrolytic voltage was-1.4 Vvs.SCE and the electrolytic time was 3 h, the electrode was stable. [ABSTRACT FROM AUTHOR]

Copyright of Industrial Minerals & Processing / Huagong Kuangwu yu Jiagong is the property of Industrial Minerals & Processing Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Disulfide bond in protein is an important post-translational modification and it is extremely essential for stabilizing the three-dimensional structure of proteins, maintaining the correct folded conformation and regulating their biological activities. Therefore, disulfide bonds assignment is of importance to understand life process and to develop protein pharmaceutical. Mass spectrometry technology can serve not only as a means cleaving the disulfide bonds, but also as an analysis tool assigning disulfide bonds connectivity. As a fragmentation means, mass spectrometry has various of MS/MS fragmentation modes. As a detector, it has the advantages of high sensitivity and high accuracy for mass spectrometry information. With these merits, mass spectrometry could fulfill the desire in the characterization of disulfide bonds. This paper summarized the mass spectrometric methods for locating disulfide bonds in proteins or peptides, according to the medium where the disulfide bonds were broken and the cleavage mechanism. Two cleavage mediums-(solution and gas phase) were divided. According to the cleavage mechanism, reduction/oxidation reaction using chemical reagents, electrochemical reduction based on electrode reaction, and post-column reduction were classified, in which disulfide bonds were cleaved in solution and the mass spectrometer was mainly used as an analysis tool. Meanwhile, molecular collision fragmentation including CID and HCD, electrons capture fragmentation (ECD and ETD), photons absorption fragmentation (e.g. MALDI-ISD and UVPD), and cleavage based on ion-ion reactions were summarized, in which disulfide bonds were cleaved in gas phase. For these methods, mass spectrometer was used not only as an analysis tool but also more importantly as a cleavage approach. This review included most disulfide bonds assignment methods and would facilitate bioinformatics-related researchers to choose an appropriate mass spectrometric method. Additionally, at the end of this paper, several new challenges in the field of disulfide bond assignment were put forward such as the characterization of multiple disulfide bonds in a short peptide, insufficient study of the disulfide bond artifacts, and the new methods based on novel instruments like UVPD. Moreover, in terms of methodological study, it would be promoted by the development of the new ionization and fragmentation technique producing new kinds of characteristic ions and corresponding data processing tools emerged in the future. Through this review, it was expected to develop more effective mass spectrometric methods for disulfide bonds characterization. [ABSTRACT FROM AUTHOR]

Copyright of Precious Metals / Guijinshu is the property of Precious Metals Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Natural Gas Industry is the property of Natural Gas Industry Journal Agency and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Tiangong University is the property of Journal of Tianjin Polytechnic University and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Clean Coal Technology is the property of Clean Coal Technology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Using aniline as monomer, ammonium persulfate as initiator, ZnCl2 and FeCl3 as metal sources, ZnFe-PANI catalyst precursor was prepared by one-step in-situ chemical polymerization method, and then ZnFe-N-C catalyst was synthesized by high temperature pyrolysis-acidification-secondary pyrolysis. The morphology and structure of the catalyst were characterized by XRD, SEM, Raman and other methods, and its catalytic performance was investigated by the electroreduction reaction of CO2. The results showed that metal doping had little effect on the morphology and structure of N-C materials, but enhanced its structural stability, increased the number of defect sites and active sites, and the area of electrochemical activity, which was conducive to the improvement of reaction performance; When the molar ratio of Zn and Fe was 3 : 1 in the precursor, the obtained sample ZnFe-N-C-3-1 had the best catalytic performance. At an overvoltage of 0.5V, the Faraday efficiency of the CO2 product by electroreduction was as high as 55 %. [ABSTRACT FROM AUTHOR]

Using aniline as monomer, ammonium persulfate as initiator, ZnCl2 and FeCl3 as metal sources, ZnFe-PANI catalyst precursor was prepared by one-step in-situ chemical polymerization method, and then ZnFe-N-C catalyst was synthesized by high temperature pyrolysis-acidification-secondary pyrolysis. The morphology and structure of the catalyst were characterized by XRD, SEM, Raman and other methods, and its catalytic performance was investigated by the electroreduction reaction of CO2. The results showed that metal doping had little effect on the morphology and structure of N-C materials, but enhanced its structural stability, increased the number of defect sites and active sites, and the area of electrochemical activity, which was conducive to the improvement of reaction performance; When the molar ratio of Zn and Fe was 3 : 1 in the precursor, the obtained sample ZnFe-N-C-3-1 had the best catalytic performance. At an overvoltage of 0.5V, the Faraday efficiency of the CO2 product by electroreduction was as high as 55 %. [ABSTRACT FROM AUTHOR]

Taking ECM GH4169 honeycomb ring as test background, the relationship between the paralled gap and two main processing parameters, the voltage and duty ratio is studied. Based on statistical probability and regression analysis principle, a parallel gap prediction model of ECM high-temperature alloy GH4169 is established, so micro-electrochemical machining technological rules conforming to actual production situation are obtained. [ABSTRACT FROM AUTHOR]