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Mineralogical characterization and pretreatment for antimony extraction by ozone of antimony-bearing refractory gold concentrates

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Transactions of Nonferrous Metals Society of China 2017年第8期27卷 1889-1896页

作者： Xue-yi GUO yun-tao xin Hao WANG Qing-hua TIAN School of Metallurgy and Environment Central South University Changsha 410083 China Cleaner Metallurgical Engineering Research Center China Nonferrous Metals Industry Association Changsha 410083 China

The mineralogical characterization of antimony-bearing refractory gold concentrates and the antimony extraction by ozonein HCl solution were *** mineralogical study shows that there exist stibnite(Sb2S3),arsenopyrite(FeAsS),pyrite(FeS2)and quartz in the concentrates,and the gold is mainly(67.42%)encapsulated in *** antimony extraction by ozone inhydrochloric acid was employed and the influences of temperature,liquid/solid ratio,HCl concentration and stirring speed on theextraction of antimony were *** antimony extraction(93.75%)is achieved under the optimized *** thepretreatment by ozone,the antimony is recovered efficiently and the gold is enriched in the leaching residue.

关键词： antimony-bearing refractory gold concentrates ozone pretreatment mineralogical characterization antimony extraction

Leaching kinetics of antimony-bearing complex sulfides ore in hydrochloric acid solution with ozone

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Transactions of Nonferrous Metals Society of China 2017年第9期27卷 2073-2081页

The leaching kinetics of Sb and Fe from antimony-bearing complex sulfides ore was investigated in HCl solution by oxidation?leaching with *** effects of temperature,HCl concentration,stirring speed and particle size on the process were *** is found that the recoveries of Sb and Fe reach86.1%and28.8%,respectively,when the reaction conditions are4.0mol/L HCl,900r/min stirring speed at85°C with<0.074mm particle size after50min *** analysis indicates that no new solid product forms in the leaching residue and the leaching process can be described by shrinking core *** leaching of Sb corresponds to diffusion-controlled model at low temperature(15?45°C)and mixed-controlled model at high temperature(45?85°C),and the apparent activation energies are6.91and17.93kJ/mol,*** leaching of Fe corresponds to diffusion-controlled model,and the apparent activation energy is1.99kJ/*** semi-empirical rate equations are obtained to describe the leaching process.

关键词： ozone antimony-bearing complex sulfides ore oxidation-leaching kinetic mixed-controlled model diffusioncontrolled model

Effect of sodium carbonate addition on carbothermic reduction of ilmenite concentrate

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Transactions of Nonferrous Metals Society of China 2022年第3期32卷 1010-1018页

作者： Xiao-dong LÜ Dan CHEN yun-tao xin Wei LÜ Xue-wei LÜ College of Materials Science and Engineering Chongqing UniversityChongqing 400044China Chongqing Key Laboratory of Vanadium−Titanium Metallurgy and Advanced Materials Chongqing UniversityChongqing 400044China

The enhanced reduction mechanism and kinetics of different Na_(2)CO_(3) additions in the carbothermic reduction of ilmenite concentrate were *** reduction process was carried out at different heating rates in a thermogravimetry facility,and the kinetics was studied using the Starink *** results indicate that Na_(2)CO_(3) addition enhanced the reduction effect as well as reduced the initial temperature of the reaction and the activation energy by increasing reactant activity in reactant form;however,it deteriorated the late-stage kinetic conditions by generating a molten phase,thereby reducing the reaction rate in the late stages of *** average apparent activation energies of ilmenite concentrate with 0%,3%,and 6%Na_(2)CO_(3) are 447,289,and 430 kJ/mol,*** results from kinetics parameters confirm that Na_(2)CO_(3) addition accelerated the reduction kinetics;however,excessive addition worsened the reduction kinetics.

关键词： ilmenite concentrate non-isothermal kinetics reduction mechanism apparent activation energy

Effect of thermo-mechanical treatment on microstructure and mechanical properties of wire-arc additively manufactured Al-Cu alloy

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Journal of Central South University 2024年第7期31卷 2181-2193页

作者： ZHANG tao QIN Zhen-yang GONG Hai WU yun-xin CHEN xin Light Alloy Research Institute Central South UniversityChangsha 410083China State Key Laboratory of Precision Manufacturing for Extreme Service Performance Central South UniversityChangsha 410083China Welding and Additive Manufacturing Centre Cranfield UniversityBedfordMK430ALUK

Wire-arc additive manufacture(WAAM)has great potential for manufacturing of Al-Cu ***,inferior mechanical properties of WAAM deposited material restrict its industrial ***-layer cold rolling and thermo-mechanical heat treatment(T8)with pre-stretching deformation between solution and aging treatment were adopted in this *** effects on hardness,mechanical properties and microstructure were analyzed and compared to the conventional heat treatment(T6).The results show that cold rolling increases the hardness and strengths,which further increase with T8 *** ultimate tensile strength(UTS)of 513 MPa and yield stress(YS)of 413 MPa can be obtained in the inter-layer cold-rolled sample with T8 treatment,which is much higher than that in the as-deposited *** cold-rolled samples show higher elongation than that of as-deposited ones due to significant elimination of porosity in cold rolling;while both the T6 and T8 treatments decrease the *** cold rolling and pre-stretching deformation both contribute to the formation of dense and dispersive precipitatedθ′phases,which inhibits the dislocation movement and enhances the strengths;as a result,T8 treatment shows better strengthening effect than the T6 *** strengthening mechanism was analyzed and it was mainly related to work hardening and precipitation strengthening.

关键词： wire-arc additive manufacture inter-layer cold rolling thermal-mechanical treatment microstructure mechanical properties strengthening mechanism

Stability constants of Sb^5+with Cl−and thermodynamics of Sb−S−Cl−H2O system involving complex behavior of Sb with Cl

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Transactions of Nonferrous Metals Society of China 2020年第12期30卷 3379-3389页

作者： Gang LI yun-tao xin Xiao-dong Lü Qing-hua TIAN Kang YAN Long-gang YE College of Materials Science and Engineering Chongqing UniversityChongqing 400044China School of Metallurgy and Environment Central South UniversityChangsha 410083China School of Metallurgical Engineering Jiangxi University of Science and TechnologyGanzhou 341000China College of Metallurgy and Material Engineering Hunan University of TechnologyZhuzhou 412007China

The stability constants of Sb^5+with Cl−as well as thermodynamics of the Sb−S−Cl−H2O system were *** stability constants of Sb5+with Cl−were obtained by theoretical calculations of the absorbance of a Sb5+-containing solution at different Cl^−concentrations,which was detected by spectrophotometric analysis at certain wavelengths of light(380 nm).The logarithmic values versus 10 of stability constants of Sb^5+with Cl−were 1.795,3.150,4.191,4.955,5.427 and 5.511,respectively,and partly filled the data gaps in the hydrometallurgy of *** presence and distribution of pentavalent antimony compounds under different conditions were analyzed based on equilibrium *** equilibrium calculations were performed for Sb−S−Cl−H2O system,which included the complex behavior of Sb with Cl,and the equilibrium equations of related reactions in this system were integrated into the potential−pH diagram.

关键词： complex behavior stability constant thermodynamics Sb−S−Cl−H2O system

Electrochemical chemoselective thiocarbamylation of late-stage Tyr-containing drugs and peptides

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Science China Chemistry 2024年第10期67卷 3382-3388页

作者： Wan-Jie Wei xin-Yu Wang Hai-tao Tang Fei-Hu Cui yun-Qi Wu Ying-Ming Pan State Key Laboratory for Chemistry and Molecular Engineering of Medicinal Resources Key Laboratory for Chemistry and Molecular Engineering of Medicinal Resources (Ministry of Education of China)Collaborative Innovation Center for Guangxi Ethnic MedicineSchool of Chemistry and Pharmaceutical SciencesGuangxi Normal University

The synthesis and modification of peptides occupy a unique position in the field of drug development, and the functionalization of amino acids is a valuable strategy as an alternative to peptide modification. Currently, the development of tyrosine(Tyr) as a target amino acid is a major challenge in the field of chemistry. Herein, we report an electrochemical radical coupling reaction of labeling tyrosine-containing active drugs and peptides with thiocarbamate derivatives for the first time. This tri-component, onepot reaction can be performed smoothly under simple, gentle, and clean electrochemical conditions and is suitable for the functionalization of various Tyr-containing drug molecular derivatives and peptides.

关键词： tyrosine electrochemical radical coupling chemical modification peptides

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An efficient online histogram publication method for data streams with local differential privacy

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Frontiers of Information Technology & Electronic Engineering 2024年第8期25卷 1096-1109页

作者： tao tao Funan ZHANG Xiujun WANG Xiao ZHENG xin ZHAO School of Computer Science and Technology Anhui University of TechnologyMaanshan 243032China Anhui Engineering Research Center for Intelligent Applications and Security of Industrial Internet Maanshan 243032China Engineering Research Institute Anhui University of TechnologyMaanshan 243032China Shengli No.1 Middle School of Dongying City Dongying 257000China

Many areas are now experiencing data streams that contain privacy-sensitive *** the sharing and release of these data are of great commercial value,if these data are released directly,the private user information in the data will be ***,how to continuously generate publishable histograms(meeting privacy protection requirements)based on sliding data stream windows has become a critical issue,especially when sending data to an untrusted third *** histogram publication methods are unsatisfactory in terms of time and storage costs,because they must cache all elements in the current sliding window(sW).Our work addresses this drawback by designing an efficient online histogram publication(EOHP)method for local differential privacy data ***,in the EOHP method,the data collector first crafts a histogram of the current SW using an approximate counting ***,the data collector reduces the privacy budget by using the optimized budget absorption mechanism and adds appropriate noise to the approximate histogram,making it possible to publish the histogram while retaining satisfactory data *** experimental results on two different real datasets show that the EOHP algorithm significantly reduces the time and storage costs and improves data utility compared to other existing algorithms.

关键词： Data stream Differential privacy Sliding windows Approximate counting

Probabilistic seismic inversion based on physics-guided deep mixture density network

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Petroleum Science 2024年第3期21卷 1611-1631页

作者： Qian-Hao Sun Zhao-yun Zong xin Li National Key Laboratory of Deep Oil and Gas China University of Petroleum(East China)Qingdao266580ShandongChina Laoshan Laboratory Qingdao266580ShandongChina CNOOC Research Institute Ltd. Beijing100028China

Deterministic inversion based on deep learning has been widely utilized in model parameters *** by logging data,seismic data,wavelet and modeling operator,deterministic inversion based on deep learning can establish nonlinear relationships between seismic data and model ***,seismic data lacks low-frequency and contains noise,which increases the non-uniqueness of the *** conventional inversion method based on deep learning can only establish the deterministic relationship between seismic data and parameters,and cannot quantify the uncertainty of *** order to quickly quantify the uncertainty,a physics-guided deep mixture density network(PG-DMDN)is established by combining the mixture density network(MDN)with the deep neural network(DNN).Compared with Bayesian neural network(BNN)and network dropout,PG-DMDN has lower computing cost and shorter training time.A low-frequency model is introduced in the training process of the network to help the network learn the nonlinear relationship between narrowband seismic data and low-frequency *** addition,the block constraints are added to the PG-DMDN framework to improve the horizontal continuity of the inversion *** illustrate the benefits of proposed method,the PG-DMDN is compared with existing semi-supervised inversion *** synthetic data examples of Marmousi II model are utilized to quantify the influence of forward modeling part,low-frequency model,noise and the pseudo-wells number on inversion results,and prove the feasibility and stability of the proposed *** addition,the robustness and generality of the proposed method are verified by the field seismic data.

关键词： Deep learning Probabilistic inversion Physics-guided Deep mixture density network

Hybrid model for BOF oxygen blowing time prediction based on oxygen balance mechanism and deep neural network

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International Journal of Minerals,Metallurgy and Materials 2024年第1期31卷 106-117页

作者： xin Shao Qing Liu Zicheng xin Jiangshan Zhang tao Zhou Shaoshuai Li State Key Laboratory of Advanced Metallurgy University of Science and Technology BeijingBeijing 100083China Engineering Research Center of MES Technology for Iron&Steel Production Ministry of EducationBeijing 100083China Laiwu Iron and Steel Group Yinshan Section Steel Co. Ltd.Jinan 271104China

The amount of oxygen blown into the converter is one of the key parameters for the control of the converter blowing process,which directly affects the tap-to-tap time of converter. In this study, a hybrid model based on oxygen balance mechanism (OBM) and deep neural network (DNN) was established for predicting oxygen blowing time in converter. A three-step method was utilized in the hybrid model. First, the oxygen consumption volume was predicted by the OBM model and DNN model, respectively. Second, a more accurate oxygen consumption volume was obtained by integrating the OBM model and DNN model. Finally, the converter oxygen blowing time was calculated according to the oxygen consumption volume and the oxygen supply intensity of each heat. The proposed hybrid model was verified using the actual data collected from an integrated steel plant in China, and compared with multiple linear regression model, OBM model, and neural network model including extreme learning machine, back propagation neural network, and DNN. The test results indicate that the hybrid model with a network structure of 3 hidden layer layers, 32-16-8 neurons per hidden layer, and 0.1 learning rate has the best prediction accuracy and stronger generalization ability compared with other models. The predicted hit ratio of oxygen consumption volume within the error±300 m^(3)is 96.67%;determination coefficient (R^(2)) and root mean square error (RMSE) are0.6984 and 150.03 m^(3), respectively. The oxygen blow time prediction hit ratio within the error±0.6 min is 89.50%;R2and RMSE are0.9486 and 0.3592 min, respectively. As a result, the proposed model can effectively predict the oxygen consumption volume and oxygen blowing time in the converter.

关键词： basic oxygen furnace oxygen consumption oxygen blowing time oxygen balance mechanism deep neural network hybrid model