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Mineral phase reconstruction behavior of direct reduction and smelting titanium slag at high temperature and slow cooling

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Rare Metals 2015年第6期34卷 440-444页

作者： Yi-Jie Wang Shu-Ming Wen qi-cheng feng Zhi-Wen Ye Min Wang State Key Laboratory of Complex Nonferrous Metal Resources Clean Utilization Kunming University of Science and Technology Faculty of Land Resource Engineering Kunming University of Science and Technology Advanced Analysis and Measurement Center Yunnan University

Titanium slag in this study was produced by subjecting titanomagnetite concentrate to direct reductionelectric furnace smelting. Processing mineralogy and mineral phase reconstruction behavior at high temperature and slow cooling treatment were examined by chemical analysis, X-ray diffraction （XRD）, optical microscopy （OM）, scanning electron microscopy （SEM）, and energydispersive spectroscopy （EDS）. Anosovite solid solution is the main titanium product by the direct reduction and smelting process. Results of slow-cooling experiments show that crystal volume and size increase as cooling rate decreases. Anosovite and gangue mineral crystals develop fully with large crystal volume and size at a cooling rate of 2 ***-1. Moreover, the growth of anosovite crystal was characterized by crystal nucleation and growth theory. These results provide further insights into the separation of anosovite from gangue by mineral processing.

关键词： Direct reduction Smelting titanium slag Anosovite Slow cooling Crystal

New influence factor inducing difficulty in selective flotation separation of Cu–Zn mixed sulfide minerals

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International Journal of Minerals,Metallurgy and Materials 2015年第2期22卷 111-115页

作者： Jiu-shuai Deng Ying-bo Mao Shu-ming Wen Jian Liu Yong-jun Xian qi-cheng feng State Key Laboratory of Complex Nonferrous Metal Resources Clean Utilization Faculty of Land Resource Engineering Kunming University of Science and Technology

Selective flotation separation of Cu-Zn mixed sulfides has been proven to be difficult. Thus far, researchers have found no satis- factory way to separate Cu-Zn mixed sulfides by selective flotation, mainly because of the complex surface and interface interaction mecha- nisms in the flotation solution. Undesired activation occurs between copper ions and the sphalerite surfaces. In addition to recycled water and mineral dissolution, ancient fluids in the minerals are observed to be a new source of metal ions. In this study, significant amounts of ancient fluids were found to exist in Cu-Zn sulfide and gangue minerals, mostly as gas-liquid fluid inclusions. The concentration of copper ions re- leased from the ancient fluids reached 1.02 × 10-6 tool/L, whereas, in the cases of sphalerite and quartz, this concentration was 0.62 ×10-6 mol/L and 0.44 × 10-6 mol/L, respectively. As a result, the ancient fluid is a significant source of copper ions compared to mineral dissolution under the same experimental conditions, which promotes the unwanted activation of sphalerite. Therefore, the ancient fluid is considered to be a new factor that affects the selective flotation separation of Cu-Zn mixed sulfide ores.

关键词： sulfide minerals flotation separation fluid inclusions

Enhanced sulfidization flotation of cuprite by surface modification with hydrogen peroxide

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Transactions of Nonferrous Metals Society of China 2021年第11期31卷 3564-3578页

作者： Guang HAN Shu-ming WEN Han WANG qi-cheng feng State Key Laboratory of Complex Nonferrous Metal Resources Clean Utilization Faculty of Land Resource EngineeringKunming University of Science and TechnologyKunming 650093China

Hydrogen peroxide was used as an oxidant to modify the cuprite surface and enhance its ***-adsorption and infrared spectroscopy measurements indicated that the modification of the cuprite surface with hydrogen peroxide before sulfidization increased the adsorption capacity of *** potential,scanning electron microscopy-energy dispersive X-ray spectroscopy,X-ray photoelectron spectroscopy,and time-of-flight secondary ion mass spectrometry results showed that the modification with hydrogen peroxide increased the contents of S^(2−)and Sn^(2−)species on the cuprite *** tests showed that the recovery of cuprite increased from 61.74%to 83.30%after the modification of the surface with hydrogen *** results confirm that the modification of the cuprite surface with hydrogen peroxide enhances the sulfidization of cuprite,which in turn improves its flotation.

关键词： cuprite flotation hydrogen peroxide surface modification sulfidization

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基于多面体可达集的时间最优模型预测控制

控制与决策 2016年第10期31卷 1884-1888页

作者：程奇峰马奥运辽宁工程技术大学电气与控制工程学院辽宁葫芦岛125105

针对有界状态干扰下的线性时变系统,提出一种新的时间最优模型预测控制算法.在离线情况下通过求解一系列的线性优化问题确定次优的多面体N步可达集,根据这些可达集在线优化计算得到的输入量使系统状态尽快收敛到稳定区域.离线求解多面... 详细信息

针对有界状态干扰下的线性时变系统,提出一种新的时间最优模型预测控制算法.在离线情况下通过求解一系列的线性优化问题确定次优的多面体N步可达集,根据这些可达集在线优化计算得到的输入量使系统状态尽快收敛到稳定区域.离线求解多面体可达集的方法可处理非对称约束,相比于以往的方法避免了在N增加时顶点数可能呈指数增多的问题,同时省去了过多复杂的多面体间的运算,因而便于在实际问题中应用.

关键词：线性时变系统有界状态干扰时间最优模型预测控制多面体可达集非对称约束

Distribution and mapping of temperate savanna in the sandy lands of eastern China

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Science China Earth Sciences 2025年第1期68卷 128-141页

作者： Xiaoya LI feng WANG Tao DUAN Kaijie YANG Bin YANG Chunmei WANG Xin TIAN qi LU Institute of Ecological Conservation and Restoration Institute of Desertification Studies Chinese Academy of Forestry Institute of Desertification Institute of Desertification Studies Chinese Academy of Forestry Institute of Great Green Wall Satellite Application Centre for Ecology and Environment MEE Institute of Microelectronics Chinese Academy of Sciences Aerospace Information Research Institute Chinese Academy of Sciences Institute of Forest Resource Information Techniques Chinese Academy of Forestry

Savannas are distributed globally across various *** perform a significant socioeconomic role in regulating net primary productivity and the terrestrial carbon *** to the high spatial heterogeneity induced by the mixed distribution of trees and grasses,current global land-cover classification maps often classify savannas as forests or grasslands Temperate savannas in China cover a vast area,yet their spatial patterns and extent remain poorly *** study developed a novel remote sensing temperate savannas mapping method by integrating very high-resolution （VHR） unmanned aerial vehicle （UAV） and GF-6 satellite imagery based on the vegetation structure characteristics of temperate savannas using the FAO definition of *** and validation datasets were collected from VHR UAV imagery covering the main temperate savannah types with a ground area of 1818 *** fractional woody vegetation cover （FWVC） and fractional herbaceous vegetation cover （FHVC） in temperate savannas were estimated by integrating Classification and Regression Tree and Random Forest *** current distribution of temperate savannas in the Horqin and Otindag Sandy Lands of Eastern China was mapped to a unit area of 0.5 *** root-mean-square error （RMSE） values for the FWVC and FHVC models were 10.69% and 11.67%,and the R2values were 0.66 and 0.63,*** assessment indicated that the new temperate savanna map had high identification accuracy,with a Kappa coefficient of 0.70,overall accuracy of 0.88,and average accuracy of *** savannas in the sandy lands of eastern China were primarily distributed in the northern Horqin Sandy Land the central and eastern regions of the Otindag Sandy Land,and the transition zone from the southern slopes of the Greater Khingan Mountains to the plains,covering a total area of 3.27×10～6 *** main savannah types were elm,oak/maple,and shrub *** savannas were widely distributed in the Otindag Sandy

关键词： Temperate savanna UAV imagery GF-6 Fractional woody vegetation cover Fractional herbaceous vegetation cover Machine learning

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Achieving ultralow leakage current in Schottky-MIS cascode anode lateral field-effect diode based on AlGaN/GaN HEMT

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Science China(Information Sciences) 2025年第1期68卷 379-385页

作者： Fangzhou WANG Changhong GAO Guojian DING cheng YU Zhuocheng WANG Xiaohui WANG qi feng Ping YU Peng ZUO Wanjun CHEN Yang WANG Haiqiang JIA Hong CHEN Bo ZHANG Zeheng WANG Songshan Lake Materials Laboratory School of Microelectronics Southern University of Science and Technology State Key Laboratory of Electronic Thin Films and Integrated Devices University of Electronic Science and Technology of China Manufacturing Commonwealth Scientific and Industrial Research Organisation

In this paper,we design and fabricate a Schottky-metal-insulator-semiconductor（MIS） cascode anode GaN lateral field-effect diode（CA-LFED） to achieve ultralow reverse leakage current(ILEAK).The device based on AlGaN/GaN highelectron-mobility-transistor（HEMT） includes a normally-off MIS-controlled channel that is cascoded with a high barrier height Schottky *** reverse bias,the high electric-field is effectively prevented by the normally-off MIS-controlled channel *** with the high barrier height Schottky contact,this feature significantly suppresses the *** by the device fabrication,the CA-LFED with high breakdown voltage（BV）>600 V shows an ultralow ILEAKof 3.6×10-9A/mm as well as a low forward voltage drop（VF） of 2.2 *** performance suggests that the CA-LFED can be a promising candidate for ultralow ILEAKand better VF-ILEAKtrade-off GaN power diode applications.

关键词： Schottky-MIS cascode anode lateral field-effect diode (LFED) ultralow reverse leakage current ($I_{\rm{LEAK}}$) forward drop and reverse leakage trade-off AlGaN/GaN HEMTs

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Atmospheric reductive catalytic fractionation of lignocellulose integrated with one-pot catalytic conversion of carbohydrate yielding valuable lignin monomers and platform chemicals from corn straw

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Green Energy & Environment 2025年第1期10卷 161-172页

作者： Meng-Ying Liu Zhe-Hui Zhang Xue-qi Wang qian Sun Chen Zhang Yu Li Zhuohua Sun Katalin Barta feng Peng Tong-qi Yuan State Key Laboratory of Efficient Production of Forest Resources Beijing Forestry UniversityBeijing100083China Beijing Key Laboratory of Lignocellulosic Chemistry Beijing Forestry UniversityBeijing100083China Department of Chemistry Organic and Bioorganic ChemistryUniversity of GrazHeinrichstrasse 28/II8010 GrazAustria

Developing a cost-effective and environmentally friendly process for the production of valuable chemicals from abundant herbal biomass receives great attentions in recent ***,taking advantage of the“lignin first”strategy,corn straw is converted to valuable chemicals including lignin monomers,furfural and 5-methoxymethylfurfural via a two steps *** key of this research lies in the development of a green and low-cost catalytic process utilizing magnetic Raney Ni catalyst and high boiling point ethylene *** utilization of neat ethylene glycol as the sole slovent under atmospheric conditions obviates the need for additional additives,thereby facilitating the entire process to be conducted in glass flasks and rendering it highly convenient for scaling *** the initial step,depolymerization of corn straw lignin resulted in a monomer yield of 18.1 wt%.Subsequently,in a dimethyl carbonate system,the carbohydrate component underwent complete conversion in a one-pot process,yielding furfural and 5-methoxymethylfurfural as the primary products with an impressive yield of 47.7%.

关键词： Atmospheric reductive catalytic fractionation Corn straw Ethylene glycol Raney Ni 5-Methoxymethylfurfural

The immunophenotypic changes and clinical effectiveness after treatment of cancer patients with infusion of human peripheral blood lymphocytes stimulated by anti-CD28 and anti-CD80 monoclonal antibodies in combination with radiotherapy and chemotherapy

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Journal of Microbiology and Immunology 2005年第2期3卷 142-147页

作者： JUN JIA LI qiONG LUO XUE LING RUAN qi feng cheng LIAN HUA XIONG TONG WANG SHU LIN HUANG Dongguan Municipal People＇s Hospital Dongguan P. R. China Guangclong Pharmaceutical university Guangzhou P. R. China

To investigate the changes on the immunopbenotypes and the clinical effects of treatment of the late cancer patients with infusion of human peripheral blood lymphocytes stimulated by anti-CD28 and anti-CD80 monoclonal antibodies in combination with radiotherapy and chemotherapy, 42 patients with late cancers were collected for study, among which 22 patients were treated with infusion of stimulated lymphocytes in combination with radiotherapy and chemotherapy. The immunological treatment procedure was given twice per week, and one course of treatment consisted of 8 times of giving infusion of lymphocytes. Another 20 patients were selected for control group, in which only radiotherapy and chemotherapy were given without lymphocyte infusions. Flow cytometry was used to examine the immunophenotypes and the clinical symptoms were observed before and after treatments. It was found that the numbers of the CD3^ ＋ , CD4^＋ cells increased, while those of the CD8 ^＋ cells decreased, with an increase of CD4/CD8 radios, but no significant difference existed in case of 22 patients treated with lymphocyte infusion as well as with radiotherapy and chemotherapy. Fifteen patients out of these 22 cases （68.18%）, the immunophenotypes changed obviously with increased numbers of CD3^ ＋ , CD4^ ＋ cells in comparison with those before treatment, and the number of CD95^ ＋ cells was increased after treatment. The PS value in this group of patients decreased after treatment. In comparison with 20 cases in the control group, the immunophenotypes showed no differences before and after treatment. While the PS value decreased obviously. Seven out of the 22 cases （31.83 % ） treated with lymphocyte infusions as well as with radiotherapy and chemotherapy illustrated no major changes in their i mmunophenotypes, compared with the situation before treatment, but the PS value also decreased. In case of treatment with lymphocyte infusions in combination with radiotherapy and chemotherapy, the alteration o

关键词： Tumor immunotherapy Radiotherapy Chemotherapy Immunophenotype Clinical situation

Equivalent combined cycle modelling for three-heat-reservoir thermal Brownian heat pump with heat-transfer effect and its optimal performance

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Science China Technological Sciences 2025年

作者： Lingen CHEN Congzheng qi Yanlin GE Huijun feng Hubei Provincial Key Laboratory of Chemical Equipment Intensification and Intrinsic Safety Wuhan Institute of Technology Hubei Provincial Engineering Technology Research Center of Green Chemical Equipment Wuhan Institute of Technology Institute of Thermal Science and Power Engineering Wuhan Institute of Technology School of Mechanical & Electrical Engineering Wuhan Institute of Technology

Because of the important role of the absorption heat pump in low-grade thermal energy utilization, this paper extends it to micro domain and performs a finite-time thermodynamic modelling for a three-heat-reservoir (THR) thermal Brownian heat pump with heat transfer effect by using an equivalent combined cycle method, which was applied for macro endoreversible THR heat pumps. The working principle and energy transformation rule are studied, and the coefficient of performance (COP) and heating load are derived. With a fixed overall thermal conductance of three heat exchangers, the maximal heating load is determined by optimizing thermal conductance distributions among three heat exchangers and barrier height, and the optimal working temperatures are also obtained. The impact of external heat transfer is elucidated to show the difference between this model and a non-equilibrium thermodynamic one. Results indicate that external heat transfer determines the energy transformation directly, and performance characteristics are closer to reality when external heat transfer is considered. The heating load has a maximal value about thermal conductance allocation ratios. About half the overall heat exchanger inventory needs to be assigned to the heat exchanger of the heating space for maximal heating load. When the cycle is with only heat transfer effect, the net particle numbers are zero, and the cycle fails to pump heat. The research results are expected to offer an idea for thermodynamic optimization and design of micro THR thermal Brownian heat pump devices.

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