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Search Results: 1 - 10 of 456957 matches for " <br>张祉倩 "
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Bacterial Pre-oxidation of Refractory Gold Concentrate from the High Altitude Areas and Cyanidation Leaching of Gold
高海拔地区难处理金精矿的细菌氧化预处理及氰化浸金

ZHANG Zhi-qian,LIU Sheng-ming,LI Chao,LI Hong-xu,WU Chao,<br>,刘升明,李超,李宏煦,吴超
过程工程学报 , 2012,
Abstract: Bacterial pre-oxidation of refractory gold ore from the high altitude areas was studied.The removal rates of Fe,S,As and cyanidation leaching rate of Au were examined under the different conditions.And the gold concentrate,oxidizing slag,and leaching residue were analyzed by XRD and SEM.The results indicated that the removal rates of Fe,S and As were up to 85% and the leaching rate of gold was 88.09%.Feasibility of bio-oxidation pretreatment in the high altitude areas was proved.Based on the experimental results,the bacterial oxidation mechanism of gold concentrates and acid solution neutralization were analyzed briefly.The bacterial oxidation of gold concentrate occurred under cooperative direct and indirect mechanism.Removal of the arsenic and heavy metal ions of liquid phase in the form of ferric arsenate and hydroxide precipitation was the main purpose of acid solution neutralization.
难浸金精矿生物浸出体系的电位-pH图分析
李超,,李宏煦
黄金科学技术 , 2014, DOI: 10.3969/j.issn.1005-2518.2014.02.077
Abstract: 电位-pH图是一种重要的热力学分析方法,能够直观地反映出浸出体系中的各种热力学平衡,有助于推断出物质发生化学反应的趋势,在难处理金精矿生物浸出体系中有重要指导作用。通过热力学计算,针对生物浸出环境绘制并分析了313K温度下,pH=0~7.0,E=-1.2~1.2V范围内适宜生物氧化黄铁矿—水系、毒砂—水系的电位-pH图。结果表明在酸性体系下黄铁矿的稳定区域存在于0.336V以下,毒砂则为0.133V以下,毒砂的稳定性比黄铁矿的稳定性低,在较低的电位条件下便会被氧化溶解。
高海拔地区难处理金精矿的细菌氧化预处理及氰化浸金
,刘升明,李超,李宏煦,吴超
过程工程学报 , 2012,
Abstract: 针对高海拔地区某难处理金精矿含砷高的特点,采用细菌氧化预处理工艺,考察在一定工艺条件下,Fe,S,As脱除率及金的氰化浸出率,并对金精矿及氧化渣、氰化渣进行了分析.结果表明,Fe,S,As脱除率均达85%以上,金氰化浸出率为88.09%,说明对该类矿物采用细菌氧化预处理工艺具有可行性.机理分析表明,细菌氧化金精矿是通过直接与间接协同作用机理;氧化酸液中和主要是将液相中砷以化学性质稳定的砷酸铁沉淀除去,将重金属离子等以氢氧化物沉淀去除.
武汉与世界城市的水景形态学对比分析
A Morphological Analysis of the Waterscape in Wuhan and Selected World Cities
 [PDF]

,
Geographical Science Research (GSER) , 2015, DOI: 10.12677/GSER.2015.42005
Abstract:
在“武汉2049”长期发展战略规划提出将在2049年将武汉打造成为世界城市的背景下,关注到大部分的世界城市不仅拥有较高的经济水平,同时也提供一个优越的软环境,如城市水环境,为居民营造高质量的景观与居住环境。由此采用同时期遥感影像,从水景形态出发,将武汉与其他世界城市及一部分国内一二线城市进行比较,以四项重要的量化指标水体量、水斑块、水陆混合度、水岸线描述案例城市的水景特征,具体比较了8个指数包括不同类型水体量、水斑块均匀度、最大斑块比、分离度、熵值、水岸线长度、边缘密度等。研究结果显示:武汉是一个具有中等水量的城市、城市水斑块均衡、拥有相当长的水岸线、水陆混合度非常高;湖区是武汉高水陆混合度的主要原因;武汉拥有其他城市不能比肩的极长水岸线,水岸线是其最重要的城市特征。基于此总结提出了武汉在水景形态影响下的三个重点发展策略。
In November 2013, Wuhan “Year of 2049” Long-term Development Strategic Plan put forward to build Wuhan a world city. Under this background, we notice that most of the world cities not only have a higher economic level, but also have a good soft ambient just like waterscape to provide high-quality landscape and life for the citizens just like New York and Chicago. This article compares Wuhan to some typical world cities and some influential Chinese urban areas in term of the waterscape to emphasize the uniqueness and advantage. First we chose some case cities, then an evaluation system was built to analyze the water data extracted from the remote sensing image including four important quantitative indicators which were raised to describe the characteristic of the waterscape. Detailed indexes include water area, patches number, largest patch index, Split, entropy and total water line and edge density. The results indicate that Wuhan is a city with fairly large water area; its patch size is quite suitable for creating high quality living space and waterfront. The mixing degree of the land and water is extremely high and the longest waterline is a unique advantage of it. Then longest water line is the most important water character. In the comparison you can see Wuhan is the only one who owns so many lakes which several layers of living space are easy to form. Based on the research conclusion, three key development strategies were brought forward to participate in the development process of Wuhan.
用于三维点云表示的扩展点特征直方图算法
, , 孙广富br>ZHUANG Zhiyun, ZHANG Jun, SUN Guangfu
- , 2016, DOI: 10.11887/j.cn.201606020
Abstract: 局部特征提取在点云相关应用中具有十分重要的作用,因此提出一种用于点云局部特征表示的扩展点特征直方图描述子。针对邻域点的两两点对提出一系列不变量;在特征点上构建一个局部参考坐标框架以获得特征描述子对旋转和平移的不变性;将关键点局部邻域划分成多个子空间,并依据每个子空间中的点对不变量构建一个直方图;将所有直方图串联起来得到扩展点特征直方图特征描述子。采用Bologna公共数据集对扩展点特征直方图特征描述子的性能进行测试,并与多个现有算法进行对比。结果表明,扩展点特征直方图特征描述子获得了良好的性能,其结果优于多个现有的特征描述子。
Local feature extraction plays an important role in related point cloud applications. Therefore, an EPFH (extended point feature histograms) descriptor for the local feature representation of 3D point cloud was proposed. Each point pair was represented by several invariant pairwise point attributes. Then, a local reference frame was defined for a keypoint and the neighboring points of the keypoint were transformed into the local reference frame. These pairwise points attributing between the neighboring points and the keypoint were accumulated into several sub features in a set of subspaces. These sub features were finally concatenated and compressed into an overall feature descriptor. The EPFH descriptor was tested by a popular publicly available Bologna dataset and was compared with several existing methods. Experimental results show that the proposed EPFH method outperforms several existing methods under different levels of noise and point cloud resolutions.
陕北毛乌素沙区生态分区及其优化结构模型研究

中国沙漠 , 1990,
Abstract: 陕北毛乌素沙区属毛乌素沙区南缘部分。东起府谷县的大昌汗,西至定边县的盐场堡,南邻陕北黄土高原,北与内蒙古伊克昭盟接壤。包括府谷、神木、榆林、横山、靖边和定边六个县的55个乡镇。总面积17903.6平方公里,沙化面积10742平方公里(其中流动沙丘面积3092平方公里,半固定沙丘面积2686.4平方公里,固定沙丘面积4923.4平方公里),约占总面积的60%。
考虑流变及塑性区扩容变化的软弱围岩复合衬砌简捷计算

铁道工程学报 , 1987,
Abstract:
试论南昆线隧道设计的几个技术问题

铁道工程学报 , 1992,
Abstract:
用逐步判别分析划分农业区的尝试——以渭南地区为例
,董瑞芳
地理研究 , 1984,
Abstract: 本文应用逐步判别分析探讨划分农业区的一般方法。文章介绍了逐步判别分析划分农业区的基本思想,模型结构,并以渭南地区为例,重点阐述了划区过程中选择因子和样本的二个关键问题。最后,对划区结果作了分析,将渭南地区分为五个一级农业区,十五个二级农业区,绘制了农业分区图。
用逐步判别分析划分农业区的尝试——以渭南地区为例
,董瑞芳
地理研究 , 1984, DOI: 10.11821/yj1984040007
Abstract: 本文应用逐步判别分析探讨划分农业区的一般方法。文章介绍了逐步判别分析划分农业区的基本思想,模型结构,并以渭南地区为例,重点阐述了划区过程中选择因子和样本的二个关键问题。最后,对划区结果作了分析,将渭南地区分为五个一级农业区,十五个二级农业区,绘制了农业分区图。
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