Isolation,purification and characterization of the hydrogen evolution promoting factor of hydrogenase ofSpirulina platensis

A component (s-factor) with obvious promoting effect on hydrogen evolution of hydrogenase has been isolated and extracted from a cell-free preparation ofSpirulina platensis. The effect of the s-factor in the reaction system is similar to that of Na₂S₂O₄, but is coupled with light. The s-factor has the maximum absorption peak at 620 nm in the oxidized state, at 590 nm in the reduced state. The partially purified s-factor showed two bands by SDS-PAGE and is distinctly different from phycocyanin, which has no change of oxidized state and reduced state absorption spectra, and also has no promoting effect on hydrogenase ofSpirulina platensis under the light. The research supported by the NSFC.     

多源数据融合的城市体检评估

融合遥感影像、社会开放大数据、统计资料等多源数据,以长沙市为例,围绕生态宜居、健康舒适、安全韧性、交通便捷、风貌特色、整洁有序、多元包容、创新活力等8个方面构建城市体检指标体系,运用归一法和层次分析法对城市自然本底和运行体征展开计算评估,结果发现：1）长沙市人居环境整体良好,城市生态宜居和整洁有序度较高,交通便捷和安全韧性建设亟需加强,风貌特色、健康舒适、创新活力、多元包容等仍有改善空间。2）各区县专题发展水平不均,在保留区域功能特色的基础上,应该着重解决发展的短板。3）城市中心城区人口密度、空气质量优良天数、万车死亡率等指标达到最高水平,但在便民服务设施完整覆盖度、住宅建筑更新和开发、群体包容等方面与城市发展需求还有一定差距。根据多源数据城市体检结果可知,长沙市未来需要以问题和需求为导向,精准治理“城市病”,努力提高城市居民生活满意度、幸福感和归属感。     

基于GWR模型的中国区域旅行社业效率空间分异及动力机制分析

基于DEA模型对中国31个省域的旅行社业效率空间分异特征进行了分析,首次运用GWR模型探索交通、资本、人才、信息化和经济动力对区域旅行社业效率影响的空间差异。结果表明：旅行社业效率在空间上具有正相关性和集聚特征,空间格局从“川”字型向“山”字型转变。各动力因子的系数均存在空间非平稳性。资本和人才动力的回归系数在空间分布上从南向北依次递减;经济动力的分布趋势为从北向南依次递减;交通动力对中西部地区旅行社效率提升的促进作用显著于东部地区;信息化动力则在东部地区表现出较强的促进作用。     

辽南早元古代花岗岩的变形温度及其构造意义

辽南早元古代辽河群中片麻状花岗岩的变形温度显示出645—690℃,550—610℃和485℃±三组温度值,表明花岗岩遭受了三幕构造变形。而区域构造解析亦表明辽河群在早元古时期经历了三幕构造变动。花岗岩的温度系列与区域变形序列具有一致性,排除了花岗岩晚期构造侵位的可能性。变形温度以550—610℃居多,意味着该幕构造形迹保存最好。第三幕变形变质作用相对较弱,仅局部出现485℃的温度值。     

BRINGING FORWARD OF THE CONCEPT OF COGIS AND ITS ARCHITECUTRE RESEARCH

Based on the analysis of the development of GIS technology and application,this paper brought forward the concept of GoGIS,namely Cooperative GIS ,CoGIS is GIS facing group-users and supporting human-human interaction,which makes it differ from the former GISs,Then,the characteristics of general Computer Spport Cooperative Work (CSCW)applications and the complexity of Geographic Information Science were analyzed,and the conclusion the CoGIS was not a simple GIS layer on CSCW was reached,Further,this paper gaver the hierarchical architecture of CoGIS,and analyzed the coperative platform in detail from the following:1)basic elements;2) collaboration patterns;3) cooperation control mechanism;4) synchronization mechanism;5) security and 6) group communication and so on.With those,the problems about GIS applications are discussed,such as 1)distributed multi-source GIS information and knowledge sharing platform;2)the fusion and visualization of GIS information;3)virtual reality cooperative modeling;4) dymamic simulation;5)expert system and 6) decision-making.Finally,this paper analyzed CoGIS application mode in brief.     

A linear tessellation model to identify spatial pattern in urban street networks

Street patterns reflect the distribution characteristics of a street network and affect the urban structure and human behavior. The recognition of street patterns has been a topic of interest for decades. In this study, a linear tessellation model is proposed to identify the spatial patterns in street networks. The street segments are broken into consecutive linear units with equal length. We define five focal operations using neighborhood analysis to extract the geometric and topological characteristics of each linear unit for the purpose of grid-pattern recognition. These are then classified by Support Vector Machine, and the result is optimized based on Gestalt principles. The experimental results demonstrate that our method is effective for mining grid patterns in a street network.     

水资源约束下的河西走廊城市经济脆弱性时空演变及其影响因素

城市经济脆弱性作为当前脆弱性研究中的重要领域,为人-地系统耦合研究提供了新的视角,并为城市可持续健康发展提供有益的决策支持和管理方法。依据城市经济脆弱性内涵,基于暴露度、敏感性、适应能力构建了城市经济脆弱性评价指标体系,运用熵权TOPSIS法评价河西走廊地区及区域内五市的城市经济脆弱性,并采用障碍度模型识别影响区域城市经济脆弱性变化的因素。结果显示：（1）2006—2015年,河西走廊地区城市经济脆弱性呈现出先曲折下降（2006—2011年）再波动上升趋势（2012—2015年）;（2）河西走廊地区的城市经济脆弱性具有明显的空间特征,经历了东西高、中部低到整体较高的演变过程;（3）阻碍河西走廊地区城市经济脆弱性降低的障碍因子由适应能力逐步转变为暴露度。针对河西走廊地区各市主要障碍因子,提出针对性优化措施。     

企业三维仿真Web GIS系统的设计

随着Internet的发展和人们对各类信息需求的增加及企业面向社会提高知名度的需要,使得企业三维仿真WebGIS系统有着较为广泛的应用前景。文章探讨了利用VisualBasic等开发企业三维仿真webGIS系统的过程和方法。     

南极长城站海雾特征分析

本文根据对海雾气象要素场、大气层结和天气形势的分析及其持续时间和季节、年际变化的统计分析,结合个例,讨论了南极长城站海雾的特征和形成机制。认为长城站海雾大多为平流冷却雾,高频率的偏北风和南大洋极锋附近显著的经向海温梯度是长城站多海雾的根本原因;夏半年海雾要多于冬半年,海雾的年际分布差异明显;海雾可出现于0-17m/s的各级风力中,3-11m/s偏北风最有利于海雾的维持;气温为-2-4℃、气-海温差为0-2℃时最易出现海雾;海雾的发生一般伴有稳定的大气层结;"东高西低"是长城站海雾的主要天气形势;海雾的持续时间取决于高压在南极半岛维持时间的长短,平均有10个小时。     

On a new species ofPavlova (Prymnesiophyceae) from China

Pavlova viridis sp. nov. is described on the basis of light and electron microscope observations. The material was collected from the coast of haiyang county of Shandong, China. It is characterized by 1) yellowish green to green chloroplast, 2) rudimentary short flagellum 0.3 μm long and hook-shaped, 3) long flagellum with small spherical knob-scales, 4) absence of pyrenoid and stigma, and 5) marine habitat. This new species andP. salina seem to be most closely related to each other but their colour, the insertion of their three appendages, the shape of their knob scales, and their cell periplasts are quite different from one another. Contribution No. 1879 from the Institute of Oceanology, Academia Sinica