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International Journal of Minerals,Metallurgy and Materials 2016年第3期23卷 241-246页

作者： Ya-li Feng Shi-yuan Zhang hao-ran li School of Civil and Environmental Engineering University of Science and Technology Beijing National Key Laboratory of Biochemical Engineering Institute of Process Engineering Chinese Academy of Sciences

Manganese （Mn） leaching and recovery from low-grade pyrolusite ore were studied using sulfiaric acid （H2SO4） as a leachant and pyrolysis-pretreated sawdust as a reductant. The effects of the dosage of pyrolysis-pretreated sawdust to pyrolusite ore, the concentration of sulfuric acid, the liquid/solid ratio, the leaching temperature, and the leaching time on manganese and iron leaching efficiencies were inves- tigated. Analysis of manganese and iron leaching efficiencies revealed that a high manganese leaching efficiency was achieved with low iron extraction. The optimal leaching efficiency was determined to be 20wt% pyrolysis-pretreated sawdust and 3.0 mol/L H2SO4 using a liq- uid/solid ratio of 6.0 mL/g for 90min at 90℃. Other low-grade pyrolusite ores were tested, and the results showed that they responded well with manganese leaching efficiencies greater than 98%.

关键词： manganese ore treatment pyrolusite sawdust pyrolysis leaching manganese

Corrected stress field intensity approach based on averaging superior limit of intrinsic damage dissipation work

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Journal of Iron and Steel Research International 2018年第10期25卷 1094-1103页

作者： hao-ran li Yan Peng Yang liu Ming Zhang National Engineering Research Center for Equipment and Technology of Cold Strip Rolling Yanshan University Qinhuangdao 066004 Hebei China

Corrected stress field intensity obtained by averaging the superior limit of intrinsic damage dissipation work in critical domain, which considers thoroughly thermodynamic consistency within irreversible thermodynamic framework, was proposed for predictions of high-cycle fatigue endurance limits. Simultaneously, the effects of mean stress, additional hardening behavior related to non-proportional loading paths and stress gradients on multiaxial high-cycle fatigue are taken into account in the proposed approach. The approach is an extension of the general stress field intensity. For a better comparison, existing multiaxial high-cycle fatigue criteria were employed to predict the endurance limits of different metallic materials subjected to different multiaxial loading paths, and it is shown that present proposal performs better from statistical value of error indexes, which make the proposed approach of corrected stress field intensity and its associated concepts provide a new conception to predict endurance limits of multiaxial high-cycle fatigue with high accuracy.

关键词： Intrinsic damage dissipation work Irreversible thermodynamic framework Corrected stress field intensity Multiaxial high-cycle fatigue Stress gradient

Dynamics of rolling mill drive system considering arc tooth gear dynamic characteristics

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Journal of Iron and Steel Research International 2019年第9期26卷 953-961页

作者： Ming Zhang Yan Peng Jian-liang Sun hao-ran li College of Mechanical and Equipment Engineering Hebei University of EngineeringHandan 056038HebeiChina National Engineering Research Center for Equipment and Technology of Cold Strip Rolling Yanshan UniversityQinhuangdao 066004HebeiChina

The arc tooth gear spindle (ATGS) is the key structure of the drive system of hot finishing rolling mills. To investigate the dynamic characteristics of ATGS of the drive system of hot finishing rolling mills, a dynamic mechanical model of ATGS was established. The influences of dynamic displacement and dynamic torque on dynamic load (meshing force, additional torque and friction torque) were studied during the non-steady-state operation of ATGS. On this basis, a dynamic model of rolling mill drive system was established considering the arc tooth gear dynamic characteristics. The dynamic response of the drive system was simulated and analyzed. The results showed that the nonlinear characteristics of ATGS were obvious;the meshing force (PX and PZ) could restrain the increase in dynamic displacement, which reflected the positive stiffness of ATGS;there was a coupling among the vertical, horizontal and torsional directions in the drive system model considering the dynamic characteristics of the arc tooth gear;the vibration intensity of ATGS in the horizontal direction is greater than that in the vertical direction when the self-excited torsional vibration happens;the greater the axial inclination angle was, the more complex the vibration mode was, and the lower the stability of the drive system was.

关键词： Rolling mill Drive system Arc tooth gear Coupling model Dynamic characteristics

Fluidized roasting reduction kinetics of low-grade pyrolusite coupling with pretreatment of stone coal

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International Journal of Minerals,Metallurgy and Materials 2013年第3期20卷 221-227页

作者： Ya-li Feng Zhen-lei Cai hao-ran li Zhu-wei Du Xin-wei liu School of Civil and Environmental Engineering University of Science and Technology Beijing State Key Laboratory of Biochemical Engineering Institute of Process Engineering Chinese Academy of Sciences

Based on the fluidized roasting reduction technology of low-grade pyrolusite coupling with pretreatment of stone coal, the manganese reduction efficiency was investigated and technical conditions were optimized. It is found that the optimum manganese reduction efficiency can be up to 98.97% under the conditions that the mass ratio of stone coal to pyrolusite is 3：1, the roasting temperature of stone coal is 1000℃, the roasting temperature of pyrolusite is 800℃, and the roasting time is 2 h. Other low-grade pyrolusite ores in China from Guangxi, Hunan, and Guizhou Provinces were tested and all these minerals responded well, giving -99% manganese reduction efficiency. Meanwhile, the reduction kinetic model has been established. It is confirmed that the reduction process is controlled by the interface chemical reaction. The apparent activation energy is 36.397 kJ/mol.

关键词： pyrolusite ore roasting ore reduction fluidized beds kinetics stone coal

Reductive leaching of low-grade manganese ore with pre-processed cornstalk

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International Journal of Minerals,Metallurgy and Materials 2015年第12期22卷 1245-1251页

作者： Ai-fei Yi Meng-ni Wu Peng-wei liu Ya-li Feng hao-ran li School of Civil and Environment Engineering University of Science and Technology Beijing State Key Laboratory of High-Efficient Mining and Safety of Metal Mines (Ministry of Education) State Key Laboratory of Biochemical Engineering Institute of Process Engineering Chinese Academy of Sciences

Cornstalk is usually directly used as a reductant in reduetive leaching manganese. However, low utilization of cornstalk makes low manganese dissolution ratio, In the research, pretreatment for cornstalk was proposed to improve manganese dissolution ratio. Cornstalk was preprocessed by a heated sulfuric acid solution （1.2 M of sulfuric acid concentration） for 10 min at 80℃. Thereafter, both the pretreated solution and the residue were used as a reductant for manganese leaching. This method not only exhibited superior activity for hydrolyzing cornstalk but also enhanced manganese dissolution. These effects were attributed to an increase in the amount of reductive sugars resulting from lignin hydrolysis. Through acid pretreatment for cornstalk, the manganese dissolution ratio was improved from 50.14% to 83.46%. The present work demonstrates for the first time the effective acid pretreatment of cornstalk to provide a cost-effective reductant for manganese leaching.

关键词： manganese ore treatment cornstalk reductants leaching

Electrochemical Cascade Annulation for the Synthesis of 3-Sulfanylquinoline Derivatives under Mild Conditions

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Chinese Journal of Chemistry 2024年第16期42卷 1833-1838页

作者： Ke li Ming-Zhong Guo Zhuo Chen hao-ran li Weisi Guo Ming li lin-Bao Zhang State Key Laboratory Base of Eco-Chemical Engineering College of Chemistry and Molecular EngineeringQingdao University of Science&TechnologyQingdaoShandong 266042China

An efficient electrochemical approach has been developed for the construction of 3-sulfanylquinoline derivatives by treating phenylethynylbenzoxazinanones with disulfides in an undivided *** protocol provided a convenient route to functionalized quinolines with good functional group ***,it does not require any metal catalysts or additives,furnishing a series of biologicalquinolines inmoderatetogoodyields.

关键词： Electrocatalysis Electrooxidation Annulation 3-Sulfany quinoline C3-thioetherification

Extraction of valuable metals from Ti-bearing blast furnace slag using ammonium sulfate pressurized pyrolysis−acid leaching processes

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Transactions of Nonferrous Metals Society of China 2020年第10期30卷 2836-2847页

作者： Zhen-zhong BIAN Ya-li FENG hao-ran li School of Civil and Resource Engineering University of Science and Technology BeijingBeijing 100083China State Key Laboratory of Biochemical Engineering Institute of Process EngineeringChinese Academy of SciencesBeijing 100190China

A novel method of extracting valuable metals from Ti-bearing blast furnace slag(TBBF slag)via pressure pyrolysis of recyclable ammonium sulfate(AS)−acid leaching process was *** results show that when pressurized roasting at an AS-to-slag mass ratio 3:1 and 370℃for 90 min,the extraction rates of titanium,aluminum and magnesium reached 94.5%,91.9%and 97.4%,*** acid leaching solution was subjected to re-crystallization in a boiling state to obtain a titanium product having a TiO2 content of 94.1%.The above crystallization mother liquor was adjusted to pH=6 and pH≥12.2,respectively,and then qualified Al2O3 and MgO products were *** analysis through XRD and SEM−EDS proves that the main phases in roasted samples were NH4AlSO4,CaSO4 and *** thermodynamic analysis presents that the main minerals of perovskite,spinel and diopside in raw ore could spontaneously react with the intermediate produced by AS under optimal conditions.

关键词： Ti-bearing blast furnace slag ammonium sulfate pressurized pyrolysis high value products

Simultaneous extraction of gold and zinc from refractory carbonaceous gold ore by chlorination roasting process

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Transactions of Nonferrous Metals Society of China 2020年第4期30卷 1111-1123页

作者： Hong-jun WANG Ya-li FENG hao-ran li Jin-xing KANG School of Civil and Resources Engineering University of Science and Technology BeijingBeijing 100083China State Key Laboratory of Biochemical Engineering Institute of Process EngineeringChinese Academy of SciencesBeijing 100190China

A novel process based on chlorination roasting was proposed to simultaneously recover gold and zinc from refractory carbonaceous gold ore by using NaCl as chlorination *** effects of roasting temperature,roasting time and NaCl content on the volatilization rates of gold and zinc were *** reaction mechanism and the phase transition process were also analyzed by means of SEM,EDS and *** results demonstrated that under the optimal conditions of NaCl content of 10%,roasting temperature of 800℃,roasting time of 4 h and gas flow rate of 1 L/min,the rates of gold and zinc were 92%and 92.56%,*** low-temperature chlorination roasting stage,a certain content of sulfur was beneficial to the chlorination reactions of gold and zinc;and during high-temperature chlorination roasting stage,the crystal structure of vanadium-bearing mica was destroyed,and the vanadium-containing oxides were beneficial to the chlorinating volatilization of gold and ***,the chlorinated volatiles of gold and zinc could be recovered by alkaline solution.

关键词： refractory carbonaceous gold ore chlorination roasting thermodynamic calculation gold zinc

“Steric Armor”Strategy of Blue Fluorescent Emitters against Photooxidation-Induced Degradation

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Chinese Journal of Chemistry 2024年第11期42卷 1223-1229页

作者： Sha-Sha Wang Jing-Rui Zhang Kuan-De Wang hao-ran li Peng-Hui Meng Yang Zhou Xiang Yu Ying Wei Quan-You Feng Yu-He Kan ling-Hai Xie Centre for Molecular Systems and Organic Devices(CMSOD) State Key Laboratory of Organic Electronics and Information Displays&Institute of Advanced MaterialsJiangsu National Synergetic Innovation Center for Advanced Materials(SICAM)Nanjing University of Posts&TelecommunicationsNanjingJiangsu210023 China Jiangsu Key Laboratory for Chemistry of Low-Dimensional Materials School of Chemistry and Chemical EngineeringHuaiyin Normal UniversityHuai'anJiangsu223300 China

Stability against oxygen is an important factor affecting the performance of organic semiconductor *** photooxidation stability can prolong the service life of the device and maintain the mechanical and photoelectric properties of the ***,various encapsulation methods from molecular structure to macroscopic device level are used to improve photooxidation ***,we adopted a crystallization strategy to allow 14H-spiro[dibenzo[c,h]acridine-7,9′-fluorene](SFDBA)to pack tightly to resist fluorescence decay caused by *** this case,the inert group of SFDBA acts as a“steric armor”,protecting the photosensitive group from being attacked by ***,compared with the fluorescence quenching of SFDBA powder under 2 h of sunlight,SFDBA crystal can maintain its fluorescence emission for more than 8 h under the same ***,the photoluminescence quantum yields(PLQYs)of the crystalline film is 327%higher than that of the amorphous *** shows that the crystallization strategy is an effective method to resist oxidation.

关键词： Organic semiconductor Photooxidation Spirocyclic aromatic hydrocarbons Crystal engineering Fluorescence

Enhancement of bio-oxidation of refractory arsenopyritic gold ore by adding pyrolusite in bioleaching system

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Transactions of Nonferrous Metals Society of China 2016年第9期26卷 2479-2484页

作者：张旭冯雅丽李浩然北京科技大学土木与环境工程学院北京100083 中国科学院过程工程研究所生化工程国家重点实验室北京100190

Pyrolusite was added in the bioleaching process to enhance the bio-oxidation process. Bioleaching tests at different dosages of pyrolusite ore, pH and inoculation amounts of Acidithiobacillus ferrooxidans were studied. The results showed that the time of the bio-oxidation process was decreased obviously and the arsenic leaching rate reached 94.4% after the bioleaching. The bio-oxidation of arsenopyrite and the effective extraction of manganese from pyrolusite were achieved by the bioleaching process. After bioleaching, the leaching rate of gold from the reaction residues reached 95.8% by cyanide leaching. In the bio-oxidation process, pyrolusite increased the redox potential of the solution to accelerate the bioleaching rate. The experiment showed that there were two reaction modes in the bioleaching process.

关键词： arsenopyritic gold ore pyrolusite bio-oxidation Acidithiobacillus ferrooxidans