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中国镉资源现状与勘查、开发、利用前景展望

中国矿业 2024年第4期33卷 51-56页

作者：于扬王登红于沨王伟刘善宝李德先江彪黄凡王岩王成辉范文辉自然资源部成矿作用与资源评价重点实验室中国地质科学院矿产资源研究所北京100037 成都理工大学地球与行星科学学院四川成都610059 四川省地质矿产(集团)有限公司四川成都610017 四川华行地质设计院有限公司四川西昌615000

镉是我国优势关键矿产,在全球新技术革命、高端制造和国防安全中占有重要战略地位,是支撑我国七大战略性新兴产业发展不可或缺的战略性矿产,也是易通过土壤-作物-食物链中的迁移、富集从而影响人体健康的重金属元素。在当今复杂的国际... 详细信息

镉是我国优势关键矿产,在全球新技术革命、高端制造和国防安全中占有重要战略地位,是支撑我国七大战略性新兴产业发展不可或缺的战略性矿产,也是易通过土壤-作物-食物链中的迁移、富集从而影响人体健康的重金属元素。在当今复杂的国际地缘政治及全球新冠肺炎疫情引发的新国际生态格局下,我国镉资源的开发利用面临着空前的挑战。一是国家战略性新兴产业发展对镉资源的需求总量仍居高位;二是世界各国资源主导权的争夺和国家高质量转型发展,迫切要求镉的开发利用由粗放型向绿色、低碳和环境友好型转变。本文梳理了中国镉资源概况,镉矿的勘查、开发、利用现状,提出镉在战略新兴产业发展领域应用潜力巨大,建议加强采矿过程中伴生镉资源的回收、废弃镉电池二次回收利用、信息、液态金属等领域的环保应用,以及提高公众、企业的环境保护、资源回收意识,并对镉开发利用前景进行了展望,旨在提升我国镉资源开发与生态环境的协调发展能力,助力战略新兴产业发展。

关键词：镉资源利用资源勘查关键矿产新质生产力

Frequency of HLA-A*03 associates with HIV-1 infection in a Chinese cohort

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Science China(Life Sciences) 2013年第11期56卷 1014-1019页

作者： ZHANG WeiLun WANG Li HONG KunXue LIU YanXin SU Bing XU che.g XU JianQin RUAN YuHua SHAO YiMin ZHENG dexian Institute of Basic Medical Sciences Chinese Academy of Medical Sciences & Peking Union Medical College State Key Laboratory for Infectious Disease Prevention and Control National Center for AIDS/STD Control and Prevention Anhui Center for Disease Control and Prevention Fuyang Center for Disease Control and Prevention

During the early mid-1990s, a number of rural farmers across central China were employed to the unregulated plasma- selling-activity and many of them were infected by HIV-1. However, AIDS progression in the former blood donors （FBDs） is various. The aim of this study is to assess human leukocyte antigen （HLA） class I allele distribution in FBDs and evaluate its association with HIV-1 infection and disease progression. A total of 353 FBDs were enrolled in the cohort including 294 ART na＇fve HIV-1 seropositive and 59 HIV-1 seronegative age-matche. subjects. The viral load and CD4/CD8 T cell counts were assessed in all subjects. Compared with HIV-seropositive group, the frequency of HLA-A＊03 in control was significantly higher. After classifying the HLA-B alleles of the subjects according to the presence of Bw4/Bw6 serological epitopes, detri- mental effect of HLA Bw6/Bw6 homozygosity was also confirmed in the HIV-seropositive subjects. This study provides nov- el evidence on HLA class I allele distribution and association of HLA-A＊03 frequency with HIV-1 infection and viremia in the HIV-1 infected FBDs, which may throw light on intervention strategy for the HIV-1 infection and our understanding how host immunity and genetic background affect HIV infection and AIDS progression.

关键词： leukocyte antigen class I HIV-1 infection viremia control Chinese former blood donor cohort

State Feedback Predictive Control for Hybrid System via Parametric Optimization

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Chinese Journal of che.ical Engineering 2005年第5期13卷 634-641页

作者：李秀改黄德先高东杰 Tsinghua University Institute of Automation Chinese Academy of Sciences

In this article, state feedback predictive controller for hybrid system via parametric programming is proposed. First, mixed logic dynamic （MLD） modeling mechanism for hybrid system is analyzed, which has a distinguished advantage to deal with the logic rules and constraints of a plant. Model predictive control algorithm with moving horizon state estimator （MHE） is presented. The estimator is adopted to estimate the current state of the plant with process disturbance and measurement noise, and the state estimated are utilized in the predictive controller for both regulation and tracking problems of the hybrid system based on MLD model. Off-line parametric programming is adopted and then on-line mixed integer programming problem can be treated as the parameter programming with estimated state as the parameters. A three tank system is used for computer simulation, results show that the proposed MHE based predictive control via parametric programming is effective for hybrid system with model/olant mismatch, and has a potential for the engineering applications.

关键词： predictive control moving horizon estimator hybrid system mixed logic dynamic parameters programming

Analysis of the characteristics of pronunciation, form and meaning in English vocabulary teaching in primary and secondary schools

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Analysis of the characteristics of pronunciation, form and m...

Atacamite and Nantokite in Kaerqueka Copper Deposit of Qimantag Area:Evidence for Cenozoic Climate Evolution of the Qaidam Basin

作者： Wang dexian Kulaike Primary School Yawa Township

The most important part of English teaching in primary and secondary schools is vocabulary teaching. A solid vocabulary foundation is the prerequisite for students to learn English well. Vocabulary learning affects students’ reading and writing exercises in English follow-up study. To improve students’ interest in learning English and their academic achievements, we must break through the mark of English vocabulary. In the process of students’ English learning, teache.s must grasp the characteristics of English vocabulary learning and help students master English vocabulary. Based on the purpose of improving students’ English teaching efficiency, this paper studies the characteristics of sound, form and meaning in English vocabulary teaching and its teaching strategies.

关键词： primary school English, vocabulary teaching Features of sound form and meaning

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Journal of Earth Science 2017年第3期28卷 492-499页

作者： Liwen Yi Xiangping Gu Anhuai Lu Xiangyu Li dexian Zhang Zhiling Wang Jianping Liu Shuai Li Zhengxiang Shu Cui Yu Hongyan Zuo Can Shen College of Resources and Environmental Sciences Hunan Normal UniversityChangsha 410081China Key Laboratory of Metallogenic Prediction of Nonferrous Metals and Geological Environment Monitor Ministry of EducationChangsha 410083China School of Geosciences and Info-Physics Central South UniversityChangsha 410083China Hunan Institute of Geological Survey Changsha 410116China

Using a mineralogy method to reflect climate evolution is a new approach to research Cenozoic environmental progression of the Qaidam Basin. In this paper, we present the che.ical composition and crystallographic parameter of atacamite, nantokite, and tenorite in cryptocrystalline aggregates from the Kaerqueka copper deposit of Qimantag metallogenic belt by means of electron microprobe and in-situ X-ray diffraction analyses. Atacamite and nantokite occur in an intimate intergrowth as the secondary precipitation of chalcopyrite and bornite filling in the interstitial space of andradite in the Kaerqueka copper deposit, with an average composition of Cl： 12.38 wt.%, Cu： 63.76 wt.%, O： 21.46 wt.%. X-ray microdiffraction shows that the intergrowth contains nantokite with a cubic unit cell a=5.403（2）？ and atacamite with an orthorhombic unit cell a=6.030（3）, b=6.883（2）, c=9.114（1）？. XRD quantitative calculation shows that the nanometric aggregate contains 36.07 wt.% tenorite, 18.41 wt.% atacamite, and 45.52 wt.% nantokite. The presence of nantokite and atacamite requires saline solutions for their formation and hyper-arid climate conditions for their preservation. Combined with the data of salt lakes and the pollen sequence of western China, we suggest that during the uplift of the Tibetan Plateau and the retreat of the Paratethys, saline water was forced to the surface through a basal fracture zone. In the hyper-arid climate of the Qaidam Basin, the recharge of groundwater by direct precipitation is negligible, and groundwater is derived from inflow from the salt lakes. Thus, atacamite is preserved. In addition, spertiniite in the edge and fractures of atacamite and nantokite may represent wetter climate after the formation of atacamite and nantokite.

关键词： atacamite nantokite climate evolution Qaidam Basin

A Novel Sche.uling Strategy for Crude Oil Blending

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Chinese Journal of che.ical Engineering 2010年第5期18卷 777-786页

作者：摆亮江永亨黄德先刘先广 Institute of Process Control Engineering Department of Automation Tsinghua University Beijing 100084 China TECHFLY Company Beijing 100083 China

For those refineries which have to deal with different types of crude oil, blending is an attractive solution to obtain a quality feedstock. In this paper, a novel sche.uling strategy is proposed for a practical crude oil blending process. The objective is to keep the property of feedstock, mainly described by the true boiling point (TBP) data, consistent and suitable. Firstly, the mathematical model is established. Then, a heuristically initialized hybrid iterative (HIHI) algorithm based on a two-level optimization structure, in which tabu search (TS) and differential evolution (DE) are used for upper-level and lower-level optimization, respectively, is proposed to get the model solution. Finally, the effectiveness and efficiency of the sche.uling strategy is validated via real data from a certain refinery.

关键词： crude oil blending sche.uling multilevel iterative algorithm intelligent optimization constrained optimization

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我国区域发展空间重组与构建中原经济区

地域研究与开发 2010年第5期29卷 1-4,10页

作者：冯德显河南省科学院地理研究所郑州450052

通过对我国发展空间变化的历程分析,探讨了我国不同历史阶段发展空间的组织形式及其动力机制。认为,我国正经历着一轮新的产业发展空间重组过程,核心动力来自于我国扩大内需战略实施、科学发展观贯彻落实和主体功能区划的国土空间开发... 详细信息

通过对我国发展空间变化的历程分析,探讨了我国不同历史阶段发展空间的组织形式及其动力机制。认为,我国正经历着一轮新的产业发展空间重组过程,核心动力来自于我国扩大内需战略实施、科学发展观贯彻落实和主体功能区划的国土空间开发思路。中部地区将成为我国新一轮空间重组过程的中心区域,获得新的发展动力,在今后较长时间内成为我国经济发展的重要支撑点。中原经济区是其空间组织核心区域之一,目前虽有政策边缘地区之不利,但具有巨大的政策创新空间,其建设对我国发展空间组织优化及其相关政策选择具有重要的理论和现实意义。

关键词：发展空间重组动力机制中原经济区政策选择

Recognition of amino acids and anions by a Zn(Ⅱ)-methylazacalix[4]pyridine complex

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Science China che.istry 2009年第10期52卷 1639-1645页

作者： GONG HanYuan, WANG dexian, HUANG ZhiTang & WANG MeiXiang Beijing National Laboratory for Molecular Sciences, CAS Laboratory of Molecular Recognition and Function, Institute of che.istry, Chinese Academy of Sciences, Beijing 100190, China Beijing National Laboratory for Molecular Sciences CAS Laboratory of Molecular Recognition and Function Institute of Chemistry Chinese Academy of Sciences Beijing China

As a powerful macrocyclic host molecule with unique conformation and cavity structure that are fine-tuned by the bridging nitrogen atoms, methylazacalix[4]pyridine (MACP-4) has been shown to selectively recognize Zn2+ and form stable Zn(Ⅱ)-MACP-4 complexes both in solid state and solution with an association constant up to 5.97 (logKs). The molecular recognition of Zn(Ⅱ)-MACP-4 complexes towards various amino acids and anions with different geometry was investigated by using the spectral titration methods and X-ray analysis. The Zn(Ⅱ)-MACP-4 complex was found to recognize the 17 amino acids tested with the association constant up to 3.97 (logKs). On the other hand, the Zn(Ⅱ)-MACP-4 complex selectively interacted with anions and the maximum association constant of 3.9 (logKs) was obtained.

关键词： Zn(Ⅱ)-MACP-4 complex amino acids anions recognition

A Dynamic Access Control Method for SDN

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Journal of Computer and Communications 2019年第10期7卷 105-115页

作者： dexian Chang Wanzhong Sun Yingjie Yang Tingting Wang Third Institute of Information Engineering University ZhengzhouChina Henan Key Laboratory of Information Security ZhengzhouChina Second Institute of Information Engineering University ZhengzhouChina The North Sea Fleet of PLA Navy QingdaoChina.

Aiming at the problem that network topology changes frequently in SDN (Software Defined Network) environment and it is difficult to implement fine-grained access control, utilizing the characteristics of SDN transfer control separation and software programming, the ABAC model (Attribute-Based Access Control) is extended by introducing security level, and the security level is defined for the attributes of subject and object to establish the access mapping relationship based on mandatory access rules. At the same time, with secure access path as SDN access control attribute, a dynamic generation method of access control path based on PSO (Particle Swarm Optimization) algorithm is designed to ensure the security of access data flow. The prototype system experiments show that the proposed method takes into account the fine-grained and dynamic requirements of SDN access control, and improves the access security of SDN while ensuring the access efficiency.

关键词： Access Control Security SDN ABAC Dynamic