长沙市商务办公空间集聚特征及其影响因素

以长沙市为研究对象,基于兴趣点（POI）数据,运用标准差椭圆分析、Getis-Ord G_i^*指数等方法识别长沙市商务办公空间结构,并借助地理加权回归分析方法探究城市空间因子对商务办公空间格局影响的空间异质性特征。结果表明：1）长沙市商务办公空间已形成“多中心”的集聚形态,呈现“一主一副两带多组团”结构,形成以湘江以东的芙蓉广场为主中心,以长沙火车站为副中心的中央商务区,湘江以西暂未形成副商务区。2）商务办公空间集聚的主导影响因素是商业空间中的购物服务、酒店等;交通条件次之,平均影响程度依次为：公交＞主干道＞对外交通＞地铁;休闲、居住职能空间中除公园绿地的正向推动作用仅次于主干道外,其余因素均较弱,其中风景名胜和住宅区的整体抑制作用明显。3）各因素总体表征为“中心―外围”的圈层影响模式,商业空间、主干道、地铁、公园绿地在中心圈层推动作用较大,影响强度与距中心的距离成反比;在外围圈层受住宅区、公交吸引形成商务办公空间集聚组团。     

Optimization of ice cuttings transportation by cable-suspended core auger drills

Ice cores contain an abundance of information about the Earth＇s climate in the past, and recovered from shallow drilling down to 300-350 m give sufficient information for reconstructing of the last climatic changes and for monitoring of pollution from human being. Cable-suspended core auger drills use an armored cable with a winch to provide power to the down-hole motor system and to retrieve the down-hole unit. Because of their lightweight, convenient transportation and installation, high penetration rates and low power consumption, core auger drills are widely used for shallow drilling in ice. Nowadays at least 14 types of auger electromechani- cal drills were designed and tested in different foreign and national glaciological laboratories. However, auger options were usually determined by experience, and the main parameters （ helix angle of the fights and rotational speed） are varied in a wide range from drill to drill. If parameters of auger are not chosen properly, poorly en- gineered drills had troubles with low efficiency of cuttings transportation, jam of ice cuttings, repeated fragmen- tation, cutters icing and stop penetration, abnormal power consumption, high rotation torques, and so on. Thus, this paper presents the method of optimization of iee cuttings transportation of cable-suspended core auger drill on the base of the theory of rotary auger. As the result, the optimal helix angle was determined correspond- ing to the rotational speed from the transportation efficiency point of view.     

Formation and evolution of sand deserts in Xinjiang,Northwest China: I. Provenances ofdesert sands简

Sandy desert landscape is a geological product of arid climate and abundant sand materials supply in natural conditions, therefore the formation of sandy desert is an ideal studying object for understanding the interaction between various stratigraphic/epigenetic spheres of the earth system. However, until now, the knowledge about the provenance and formation of these deserts in Xinjiang, Central Asia is diverse and inconsistent, a systematic review is necessary. Ancient aeolian sand sediments in the internal areas of these deserts and their twin dust deposits in the Cenozoic strata surrounding the Xinjiang deserts are direct and indirect clues reflecting the provenance of sand materials and the formation and evolution of deserts. Based on the geochemical, mineralogical and isotopic evidences of desert sands and relevant deposits in the peripheral regions, this paper reviews the research progress on the development of the sandy deserts in Xinjiang, Northwest China. Many proofs proposed that desert sands in Xinjiang were mainly sourced from the ancient pluvial, alluvial and fluvial sediments and were eventually achieved because of the local sand supply. It pointed out that the settings of tectonic structure in Xinjiang had made sediments both in the Tarim Basin and the Junggar Basin being influenced greatly by regional hydrological system and aeolian processes originated from the planetary wind system of westerly, the East Asian winter monsoon and the topographical mountain-valley winds. However, the directions of transpor- tation paths are different between the hydrological dynamics and the aeolian dynamics, which are decided by the slantwise structures of the basins tectonics and the regional atmospheric circulation routes, respectively, and have determined anisotropies of the transport pathway of these sediments delivered by different agents. This results in a geological cycle of detrital sediment transportation in the two large sediment mixing, alternation and recycle basins and thus largely increases the degree of between younger and older sediment sources, as well as the complexity and diversity of sand provenances.     

新疆地区沙漠的形成与演化——I.沙漠沙的物源（英文）

Abstract:Sandy desert landscape is a geological product of arid climate and abundant sand materials supply in natural conditions,therefore the formation of sandy desert is an ideal studying object for understanding the interaction between various stratigraphic/epigenetic spheres of the earth system.However,until now,the knowledge about the provenance and formation of these deserts in Xinjiang,Central Asia is diverse and inconsistent,a systematic review is necessary.Ancient aeolian sand sediments in the internal areas of these deserts and their twin dust deposits in the Cenozoic strata surrounding the Xinjiang deserts are direct and indirect clues reflecting the provenance of sand materials and the formation and evolution of deserts.Based on the geochemical,mineralogical and isotopic evidences of desert sands and relevant deposits in the peripheral regions,this paper reviews the research progress on the development of the sandy deserts in Xinjiang,Northwest China.Many proofs proposed that desert sands in Xinjiang were mainly sourced from the ancient pluvial,alluvial and fluvial sediments and were eventually achieved because of the local sand supply.It pointed out that the settings of tectonic structure in Xinjiang had made sediments both in the Tarim Basin and the Junggar Basin being influenced greatly by regional hydrological system and aeolian processes originated from the planetary wind system of westerly,the East Asian winter monsoon and the topographical mountain-valley winds.However,the directions of transportation paths are different between the hydrological dynamics and the aeolian dynamics,which are decided by the slantwise structures of the basins tectonics and the regional atmospheric circulation routes,respectively,and have determined anisotropies of the transport pathway of these sediments delivered by different agents.This results in a geological cycle of detrital sediment transportation in the two large basins and thus largely increases the degree of sediment mixing,alternation and recycle between younger and older sediment sources,as wellas the complexity and diversity of sand provenances.     

防波堤建设对海底泥沙冲淤环境影响研究

以烟台八角海域为例,分别采用数值模拟计算与实测值对比两种方式分析评价防波堤建设对海底冲淤变化的影响。研究结果表明,防波堤建设导致研究区海底沉积物由原来的平衡状态转变为"浅水冲深水淤"的态势,冲刷及淤积速率均为0~0.06m/a。除构筑物附近等边界区域外,模型计算结果与实测泥沙运移趋势基本一致。     

试析我国液化天然气的海上运输

作为管道天然气的有益补充,液化天然气（LNG）全球贸易量逐年增加。LNG不仅是我国实现能源安全供应的有效保障,也是国家能源战略的重要组成部分。但我国LNG目前发展面临三大能源安全保障压力,一是进口来源相对集中,气源保障抗风险能力不足;二是LNG运输船队规模小,自主运输能力不足;三是海上自主运输线路单一,进口通道易受制于人。为此,本文从加强进口来源多元化和建立自主运输船队两方面提出了对策建议。     

北京城区公共交通满意度模型与空间结构评价

以北京市城八氏的公共交通为切入点.探索了城市空间结构的评价分析方法.通过"公共交通可达性"指标.将城市实体空间结构的指标与居民对公共交通的满意度连系起来.建立了以满意度为目标的城市空间结构评价体系.并对提升城市空间结构的实体空间因子进行了实证分析.首先,对"公共交通可达性"的各项影响因子进行了梳理,从公共交通服务质量、区域经济特征、道路建设三个方面,提出了包括公交通达度、人口和经济集聚度、道路密度、区位指标等在内的城市公共交通可达性的评价指标体系.其次,构建了以居民满意度为因变量的公共交通可达性评价模型.分析定量揭示了公交站点配置、公交通达度、经济密度等凶素对了:城市空间结构的优化作用.同时分析表明.公共交通的优化需充分考虑不同属性的居民群体的空间分布规律.据此,从城市空间结构评价的角度分析了北京市公共交通中存在的问题,并提出如下建议:①市政交通规划的重点应放在五环以内地区;②实现800m公交站点服务面积全覆盖;③加强各地与市区重要功能节点的公共交通联系来提高其通达度;④根据居民的分布和属性特征出台相应的公交服务政策提高不同居民群体的公共交通满意度.     

酸性氨基酸在铜、铅、锌迁移与沉积过程中的作用

对酸性氨基酸(谷氨酸)在铜、铅、锌迁移与沉积过程中的作用,进行了模拟实验研究。结果表明,酸性氨基酸在热卤水中的存在,比中性氨基酸更有利于铜、铅、锌的活化迁移。但是,随作用时间,特别是随温度的变化,不同金属在热液中的活化迁移情况则明显地不同。这表明金属与氮基酸形成的易溶络合物,其稳定性不仅与金属和氨基酸的种类有关,而且还受温度的直接影响。     

浅谈陆相湖盆深水重力流沉积研究中的几点认识

与海相盆地重力流沉积研究理论的快速发展相比,陆相湖盆重力流沉积的相关认识还存在着一定差距。综合国内、外重力流沉积相关研究成果,总结湖盆重力流沉积的相关认识,以明确湖盆重力流沉积研究中存在的不足。增强不同术语内涵及相互关系的理解、增加不同术语的解释说明,是减少术语混淆的有效途径;流体转化、流态转化和润滑作用是湖盆重力流搬运的主要动力学过程;受阻沉降、湍流抑制和牵引毯作用是湖盆重力流沉积物沉降的重要动力学过程。沉积物再搬运、洪水持续供给、漂浮羽流卸载是陆相湖盆重力流沉积主要的成因机制;重力流沉积相域类型、块状砂岩内部沉积特征和逆正粒序沉积特征精细解析可揭示重力流沉积成因。超临界浊流侵蚀作用形成重力流水道,盆地外部因素主控重力流物质成分和来源,盆地内部因素主控重力流分异效率,其综合表现形式即“源—汇”系统控制下的重力流砂体形成演化过程。洪水持续供给成因重力流沉积模式以重力流水道—堤岸沉积、水道—朵叶转换带和朵叶沉积依次过渡构成其典型沉积构型要素组合;沉积物再搬运成因沉积模式以三角洲前缘垮塌带、混杂沉积和朵叶沉积依次过渡构成其典型沉积构型要素组合。湖盆重力流沉积是非常规油气赋存的重要场所,流体转化成因的细粒沉积具有易于油气生成和富集,且易于压裂的先天优势,可能是页岩油气中的“甜点”区发育的优势沉积岩相组合类型。     

中国能源保障基本形势分析

国家能源保障目标由两部分组成： 第一,能源供应的稳定性,指满足国家人口发展正常需 求的能源供应保障的稳定程度;第二,能源使用的安全性,指能源消费及使用不应对人类自身的 生存与发展环境构成任何威胁。本文从影响能源保障的能源资源基础、生产与消费、运输、生产与 消费对环境影响等方面分析了中国能源保障的基本形势, 总体来说中国目前能源保障重点集中 在能源供应保障层面上, 立足于自身的资源基础及生产与消费空间高度分离的特点建立起了庞 大的能源保障体系, 对能源使用安全尽管已经引起了高度的重视, 但是由于现实经济的压力和认 识上的不足实质性的措施还很少。未来我国应该立足能源保障基本形势, 从供应稳定性和使用安 全性出发构筑稳定、经济、清洁、安全的能源保障体系。