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Zinc extraction from zinc oxidized ore using(NH4)2SO4 roasting−leaching process

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International Journal of Minerals,Metallurgy and Materials 2020年第11期27卷 1471-1481页

作者： Xiao-yi Shen Hong-mei Shao Ji-wen Ding Yan Liu Hui-min gu Yu-chun Zhai Key Laboratory for Ecological Utilization of Multimetallic Mineral of Ministry of Education School of MetallurgyNortheastern UniversityShenyang 110819China School of Environmental and Chemical Engineering Shenyang Ligong UniversityShenyang 110159China School of Computer Science and Engineering Northeastern UniversityShenyang 110819China

An improved method of(NH4)2SO4 roasting followed by water leaching to utilize zinc oxidized ores was *** operating parameters were obtained by investigating the effects of the molar ratio of(NH4)2SO4 to zinc,roasting temperature,and holding time on zinc *** roasting process followed the chemical reaction control mechanism with the apparent activation energy value of 41.74 kJ·mol^−*** transformation of mineral phases in roasting was identified by X-ray diffraction analysis combined with thermogravimetry–differential thermal analysis *** water leaching conditions,including the leaching temperature,leaching time,stirring velocity,and liquid-to-solid ratio,were discussed,and the leaching kinetics was *** reaction rate was obtained under outer diffusion without product layer control;the values of the apparent activation energy for two stages were 4.12 and 8.19 kJ·mol^−*** maximum zinc extraction ratio reached 96%while the efficiency of iron extraction was approximately 32%under appropriate *** work offers an effective method for the comprehensive use of zinc oxidized ores.

关键词： zinc oxidized ore ammonium sulfate roasting,water leaching kinetics mechanism extraction ratio

The precise regulation of different COR genes by individual CBF transcription factors in Arabidopsis thaliana

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Journal of Integrative Plant Biology 2017年第2期59卷 118-133页

作者： Yihao Shi Jiaying Huang Tianshu Sun Xuefei Wang Chenqi Zhu Yuxi Ai Hongya gu State Key Laboratory for Protein and Plant Gene Research College of Life Sciences Peking University Beijing 100871 China

The transcription factors CBF1/2/3 are reported to play a dominant role in the cold responsive network of Arabidopsis by directly regulating the expression levels of cold responsive （COR） genes. In this study, we obtained CRISPR/Casg-mediated loss-of-function mutants of cbf1-3. Over 3,ooo COR genes identified by RNA-seq analysis showed a slight but significant change in their expression levels in the mutants compared to the wild- type plants after being treated at 4 ℃ for 12 h. The C-repeat （CRT） motif （5＇-CCGAC-3＇） was enriched in promoters of genes that were up-regulated by CBF2 and CBF3 but not in promoters of genes up-regulated by CBFI. These data suggest that CBF2 and CBF3 play a more important role in directing the cold response by regulating different sets of downstream COR genes. More than 2/3 of COR genes were co-regulated by two or three CBFs and were involved mainly in cellular signal transduction and metabolic processes; less than 1[3 of the genes were regulated by one CBF, and those genes up-regulated were enriched in cold-related abiotic stress responses. Our results indicate that CBFs play an important role in the trade-off between cold tolerance and plant growth through the precise regulation of COR genes in the complicated transcriptional network.

关键词： CRISPR Cas9 CBF cold tolerance COR single CBF-regulated genes

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基于聚类的动态社交网络隐私保护方法

通信学报 2015年第S1期36卷 126-130页

作者：谷勇浩林九川郭达北京邮电大学计算机学院智能通信软件与多媒体北京市重点实验室北京100876 公安部第三研究所上海201204 北京邮电大学电子工程学院北京100876

由于社交网络图结构的动态变化特性,需要采用有效的动态隐私保护方法。针对现有动态数据发布隐私保护方法中存在的攻击者背景知识单一、对图结构动态变化适应性较低等问题,提出基于聚类的动态图发布隐私保护方法。分析表明,该方法能抵... 详细信息

由于社交网络图结构的动态变化特性,需要采用有效的动态隐私保护方法。针对现有动态数据发布隐私保护方法中存在的攻击者背景知识单一、对图结构动态变化适应性较低等问题,提出基于聚类的动态图发布隐私保护方法。分析表明,该方法能抵御多种背景知识攻击,同时对社交网络图结构动态变化具有较好的适应性。

关键词：动态社交网络隐私保护聚类信息损失度隐匿率

Data-Driven Collaborative Scheduling Method for Multi-Satellite Data-Transmission

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Tsinghua Science and Technology 2024年第5期29卷 1463-1480页

作者： Xiaoyu Chen Weichao gu guangming Dai Lining Xing Tian Tian Weilai Luo Shi Cheng Mengyun Zhou School of Computer Science China University of GeosciencesWuhan 430074China School of Electronic Engineering Xidian UniversityXi’an 710071China School of Computer Science Shaanxi Normal UniversityTaiyuan 710119China

With continuous expansion of satellite applications,the requirements for satellite communication services,such as communication delay,transmission bandwidth,transmission power consumption,and communication coverage,are becoming *** paper first presents an overview of the current development status of Low Earth Orbit(LEO)satellite constellations,and then conducts a demand analysis for multi-satellite data transmission based on LEO satellite *** problem is described,and the challenges and difficulties of the problem are analyzed *** this basis,a multi-satellite data-transmission mathematical model is then *** classical heuristic allocating strategies on the features of the proposed model,with the reinforcement learning algorithm Deep Q-Network(DQN),a two-stage optimization framework based on heuristic and DQN is ***,by taking into account the spatial and temporal distribution characteristics of satellite and facility resources,a multi-satellite scheduling instance dataset is *** results validate the rationality and correctness of the DQN algorithm in solving the collaborative scheduling problem of multi-satellite data transmission.

关键词： relay satellite scheduling data transmission Deep Q-Network(DQN) Genetic Algorithm(GA)

Comparative Analysis of Codon Usage Patterns Among Mitochondrion, Chloroplast and Nuclear Genes

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Journal of Integrative Plant Biology 2007年第2期49卷 246-254页

作者： Wen-Juan Zhang Jie Zhou Zuo-Feng Li Li Wang Xun gu Yang Zhong Ministry of Education Key Laboratory for Biodiversity Science and Ecological Engineering School of Life Sciences Fudan University Shanghai 200433 China Department of Genetics and Cell Biology Center for Bioinformatics and Biological Statistics Iowa State University Ames IA 50011 USA Shanghai Center for Bioinformation Technology Shanghai 201203 China

In many organisms, the difference in codon usage patterns among genes reflects variation in local base compositional biases and the intensity of natural selection. In this study, a comparative analysis was performed to investigate the characteristics of codon bias and factors in shaping the codon usage patterns among mitochondrion, chloroplast and nuclear genes in common wheat （Triticum aestivum L.）. GC contents in nuclear genes were higher than that in mitochondrion and chloroplast genes. The neutrality and correspondence analyses indicated that the codon usage in nuclear genes would be a result of relative strong mutational bias, while the codon usage patterns of mitochondrion and chloroplast genes were more conserved in GC content and influenced by translation level. The Parity Rule 2 （PR2） plot analysis showed that pyrimidines were used more frequently than purines at the third codon position in the three genomes. In addition, using a new alterative strategy, 11, 12, and 24 triplets were defined as preferred codons in the mitochondrion, chloroplast and nuclear genes, respectively. These findings suggested that the mitochondrion, chloroplast and nuclear genes shared particularly different features of codon usage and evolutionary constraints.

关键词： chloroplast codon usage mitochondrion neutral mutation nuclear gene selection constraint Triticum aestivum.

Wind-resistant studies on tall buildings and structures

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Science China(Technological Sciences) 2010年第10期53卷 2630-2646页

作者： gu Ming State Key Laboratory of Disaster Reduction in Civil Engineering, Tongji University, Shanghai 200092, China 1. State Key Laboratory of Disaster Reduction in Civil Engineering Tongji University Shanghai 200092 China

This paper introduces some aspects of wind-resistant studies of our research team on tall buildings and structures. Wind tunnel tests were carried out on 27 typical tall building models by using wind pressure scanning and HFFB techniques. The characteristics of wind pressures and forces acting on these buildings were analyzed. Some results have been adopted in a Shanghai code for structural design of steel tall buildings. Interference effects on wind forces and wind pressures among two and three tall buildings were experimentally investigated with about 10000 testing conditions. Regression analyses of the interference factors under different parameter conditions were made and the main regression formulas are presented. Theoretical study on equivalent static wind loads of tall buildings and structures are then introduced. Especially,a new concept of "mode coupling factor" and a modified SRSS method for wind response and equivalent static wind load of complicated tall buildings and structures with consideration of multi mode contributions and their coupling effects are presented. Finally,practical applications of wind-resistant studies on tall building and structures,taking the guangzhou New TV Tower as an example,are presented.

关键词： tall building and structure wind pressure and force interference effect equivalent static wind load application

Inorganic Nanozyme with Combined Self-Oxygenation/Degradable Capabilities for Sensitized Cancer Immunochemotherapy

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Nano-Micro Letters 2019年第4期11卷 308-325页

作者： Jie Wang Lan Fang Ping Li Lang Ma Weidan Na Chong Cheng Yueqing gu Dawei Deng Department of Pharmaceutical Engineering and Department of Biomedical Engineering School of EngineeringChina Pharmaceutical UniversityNanjing 211198People’s Republic of China Institute of Chemistry and Biochemistry Freie Universitat BerlinTakustrasse 314195 BerlinGermany State Key Laboratory of Polymer Materials Engineering College of Polymer Science and EngineeringSichuan UniversityChengdu 610065People’s Republic of China State Key Laboratory of Natural Medicines National R&D Center for Chinese Herbal Medicine ProcessingChina Pharmaceutical UniversityNanjing 211198People’s Republic of China

Recently emerged cancer immunochemotherapy has provided enormous new possibilities to replace traditional chemotherapy in fighting ***,the treatment efficacy is hampered by tumor hypoxiainduced immunosuppression in tumor microenvironment(TME).Herein,we fabricated a self-oxygenation/degradable inorganic nanozyme with a core-shell structure to relieve tumor hypoxia in cancer *** integrating the biocompatible CaO2 as the oxygen-storing component,this strategy is more effective than the earlier designed nanocarriers for delivering oxygen or H2O2,and thus provides remarkable oxygenation and long-term capability in relieving hypoxia throughout the tumor ***,in vivo tests validate that the delivery system can successfully relieve hypoxia and reverse the immunosuppressive TME to favor antitumor immune responses,leading to enhanced chemoimmunotherapy with cytotoxic T lymphocyte-associated antigen 4 ***,a facile,robust and effective strategy is proposed to improve tumor oxygenation by using self-decomposable and biocompatible inorganic nanozyme reactor,which will not only provide an innovative pathway to relieve intratumoral hypoxia,but also present potential applications in other oxygen-favored cancer therapies or oxygen deficiency-originated diseases.

关键词： Inorganic nanozyme Self-oxygenation nanoreactor Biodegradable nanomedicine Immunochemotherapy Cancer treatment

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基于刚度衰减下的桁架系统的疲劳可靠性分析

兵工学报 2007年第12期28卷 1478-1482页

作者：安海安伟光顾永维哈尔滨工程大学航天工程系哈尔滨黑龙江150001

在疲劳载荷作用下,元件物理性能的衰减过程是十分复杂的,而由元件组成的结构系统不是一个简单的拓扑结构,其物理性能在疲劳载荷作用下的变化更为复杂。为了定量分析结构系统在不同寿命期内的刚度可靠性,建立起结构物理性能衰减的精确公... 详细信息

在疲劳载荷作用下,元件物理性能的衰减过程是十分复杂的,而由元件组成的结构系统不是一个简单的拓扑结构,其物理性能在疲劳载荷作用下的变化更为复杂。为了定量分析结构系统在不同寿命期内的刚度可靠性,建立起结构物理性能衰减的精确公式是至关重要的。本文从损伤力学角度出发,结合断裂力学中理论断裂强度公式,利用应变等效性假设,基于剩余强度衰减模型,推导出弹性模量衰减公式,从而给出了疲劳载荷作用下系统刚度的可靠性衰减公式。最后,结合杆元桁架系统刚度矩阵,推导出桁架系统节点位移在不同使用寿命期的计算公式,进而求出系统刚度的疲劳可靠性指标。

关键词：固体力学应变等效性假设剩余强度弹性模量衰减刚度疲劳可靠性

Fabrication of stable MWCNT bucky paper for solar-driven interfacial evaporation by coupling c-ray irradiation with borate crosslinking

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Nuclear Science and Techniques 2021年第12期32卷 13-25页

作者： Yu-Qing Qiao Yu gu Yu-Sen Meng Hai-Xia Li Bo-Wu Zhang Jing-Ye Li MOE Key Lab of Resource Chemistry Shanghai Key Lab of Rare Earth Functional MaterialsCollege of Chemistry and Materials ScienceShanghai Normal UniversityShanghai 200234China Yellow River Institute of Eco-Environmental Research Yellow River Basin Ecology and Environment AdministrationZhengzhou 450000China Shanghai Institute of Applied Physics Chinese Academy of SciencesShanghai 201800China School of Civil and Architectural Engineering Nanjing Tech University Pujiang InstituteNanjing 211134China

Herein,we report a facile solution process for preparing multi-walled carbon nanotube(MWCNT)bucky paper for solar-driven interfacial water *** process involves vacuum filtrating a dispersion of MWCNTs that was modified by polyvinyl alcohol(PVA)under c-ray irradiation on a cellulose acetate microporous membrane,followed by borate *** transform infrared spectroscopy,Raman spectroscopy,and thermogravimetry confirmed the success of PVA grafting onto MWCNTs and borate crosslinking between modified MWCNT *** as-prepared crosslinked MWCNT bucky papers(BBP membranes)were used as a solar absorber,by placing them on a paper-wrapped floating platform,for interfacial water evaporation under simulated solar *** BBP membranes showed good water tolerance and mechanical stability,with an evaporation rate of 0.79 kg m^(-2)h^(-1)and an evaporation efficiency of 56%under 1 sun illumination in deionized ***,the BBP membranes achieved an evaporation rate of 0.76 kg m^(-2)h^(-1)in both NaCl solution(3.5 wt%)and sulfuric acid solution(1 mol L-1),demonstrating their impressive applicability for water reclamation from brine and acidic *** evaporation rate of 0.70 kg m-2 h-1(very close to that from deionized water)was obtained from the solar evaporation of saturated NaCl solution,and the BBP membrane exhibited unexpected stability without the inference of salt accumulation on the membrane surface during long-term continuous solar evaporation.

关键词： c-ray irradiation Multi-walled carbon nanotubes Bucky paper Solar-driven interfacial water evaporation Desalination