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西沙群岛珊瑚类的研究 Ⅰ.铁星珊瑚科的一个新属和两个新种

解放以来，我国有关单位对西沙群岛作了一系列的调查。我所在1973、1974年对西沙群岛也进行过多次调查，获得了不少造礁珊瑚的标本及有关资料。本文先报道有关西沙群岛的造礁石珊瑚的一个新属及两个新种，其他的种类将陆续报道。     

A relative spatial access assessment approach for analyzing potential spatial access to colorectal cancer services in Texas

The usefulness of gravity-based spatial access models is limited because of the uncertainty introduced by the range of values of the impedance coefficient. To solve this problem, this paper proposes the concept of spatial access ratio (SPAR) derived from the enhanced 2-step floating catchment area (E2SFCA) method — a recent extension of the gravity model — to assess potential spatial access. First, a sensitivity assessment is conducted to verify the effectiveness of SPAR and its advantages in overcoming the uncertainty problem. Then, the E2SFCA method and the shortest travel time method are employed to measure potential spatial access to colorectal cancer (CRC) prevention and treatment services in Texas based on data at the census tract level. The socio-demographic and geographic distributions of potential spatial access to CRC services are also examined. The sensitivity assessment reveals substantial fluctuations in the values of the spatial access index calculated directly by the E2SFCA method under different values of the impedance coefficient. However, the values of SPAR remain stable under different values of the coefficient. A comparative analysis indicates that potential spatial access to primary care physicians (PCPs), CRC screening facilities, and oncologists varied among different racial/ethnic and socioeconomic population groups as well as in different geographic regions in Texas. Non-Hispanic blacks, Asians, and people in affluent areas had a geographical advantage in accessing CRC services than other groups. The urban/rural difference was more obvious and serious than those of different racial/ethnic groups and groups with different socio-economic statuses, as metropolitan residents had more than three times the potential spatial access than isolated rural residents.     

Acoustic Emission and Energy Dissipation Characteristics of Gas-Bearing Coal Samples Under Different Cyclic Loading Paths

Natural Resources Research - Cyclic loading widely exists in coal mining activities, and it can significantly change the mechanical and seepage characteristics of coal. In this study, raw...     

Anomalous eastward displacement of the tropical western Pacific warm pool and warming of the tropical eastern Pacific

INTRODUCTIONSincetheTOGA-COARElOP(October1992--March1993),usingthelOPdatamanyscientistshaveanalyzedthedifferenttimescaleair-seainteractionduringoccurringanddevelopingperiodof1992/1993EINifio,andespeciallyemphasizedtheintraseasonalvariation(Wuetal.,1993;Liu,1993;WuandSheng,1993).ThishasgottenanewunderstandingoftheEINino*ThisworkissupportedbytheNationalKeyProjectStudiesonShort-rangeClimatePredictionSysteminChinaundercontractNo.96--908-04-02--2.1.FirstinstituteofOceanography,S…     

HY-2卫星散射计热带气旋自动识别算法

对基于HY-2卫星散射计风矢量产品的热带气旋自动识别算法进行了研究。算法分为粗搜索与精搜索两部分。粗搜索利用热带气旋风场的风速与风向分布直方图特征确定搜索的阈值,快速剔除比较容易识别的非热带气旋区域。在此基础上,精搜索利用热带气旋风向的螺旋状分布特征,通过搜索目标区域内是否存在螺旋状流线的方法,确定目标区域的风向是否存在螺旋状流线特征,从而实现对热带气旋的准确自动识别。作为示例,将该方法应用到对HY-2散射计观测到的2012年6号强热带风暴"杜苏芮"的自动识别,结果表明,本文提出的算法可以从HY-2散射计风场数据中准确有效的自动识别出热带气旋。     

莱州湾南岸中全新世聚落遗址时空分布特征及其环境背景

基于ArcGIS10.3平台对莱州湾南岸中全新世聚落遗址的高程、坡度、坡向、濒河度等指标进行分析,得出该时期聚落遗址的时空分布及演变特征,并结合全新世莱州湾南岸的环境背景,探讨全新世环境演变对聚落遗址分布及演变的影响。研究表明：① 全新世莱州湾南岸的聚落遗址数量、出现频率及在总数中的比重基本呈现明显的先增后降的倒V型（非对称）变化趋势。② 遗址高程分布具有一定的规律性,几乎所有时期的遗址点均分布于高程范围在0~29 m的地区,而大汶口文化时期遗址高程分布范围为10~29 m。从坡度来看,聚落遗址主要分布于坡度范围在0~4°的平缓地区;从坡向来看,古人大多集中在南向、东南向和西南向的位置。后李文化至龙山文化时期,河流对聚落选址的影响程度逐渐降低。③ 8.5~6.9 ka B.P.气候总体进入温暖期,且冷暖波动,干湿交替,后李文化由此得到发展;6.9~4.5 ka B.P.出现了短暂的降温,但整体较温和,优越的自然条件促进了大汶口文化的发展;4.5~4.0 ka B.P.左右气候条件较大汶口文化时期略干,但在此基础上新石器文化仍得到进一步发展,并于龙山文化时期进入鼎盛阶段;4.0 ka B.P.左右气候突变,出现剧烈降温事件,变化幅度超出了人类的适应能力,岳石文化随之衰落。④ 海水入侵限制了人类活动,而古湖泊和古河道的形成为古人生活质量的提高创造了天然条件。     

秋季南黄海水文特征及海水的混合与交换

根据1996年10月中韩合作调查获得的CTD资料,分析探讨了南黄海秋季跃层的分布特征及垂直混合状况,同时对黄海冷水团的垂向混合进行了初步探讨.还利用改进后的逐步聚类分析法划分了表、底层水团,确定了各水团的温度、盐度、溶解氧和PH值4要素的平均特征值,并根据各水团的特性和温度、盐度的平面分布特征,重点探讨了黄海水与沿岸水及东海水的混合和交换.     

Charging of oil fields surrounding the Shaleitian uplift from multiple source rock intervals and generative kitchens,Bohai Bay basin,China

This paper discusses origin and charging directions of oil fields on the Shaleitian Uplift, Bohai Bay basin. The Shaleitian Uplift is a footwall uplift surrounded by three sags containing mature source rocks. The origins of the four oil fields on the Shaleitian Uplift, both in terms of source rock intervals and in terms of generative kitchens, were studied using biomarker distributions for 61 source rock samples and 27 oil samples. Hierarchical cluster analysis using 12 parameters known to be effective indicators of organic matter input and/or depositional conditions allowed the identification of six oil types or classes. These six oil classes could then be linked to three distinct source rock intervals ranging in age from 43.0 Ma to 30.3 Ma. The third member (43.0–38.0 Ma in age) and first member (35.8–32.8 Ma) of the Eocene Shahejie Formation, and the third member of the Oligocene Dongying Formation (32.8–30.3 Ma) each sourced one class of oil. The other three classes represent mixtures of oil generated from multiple source rock intervals. Traps on the Shaleitian Uplift were charged in the east by oil generated from the Eocene Shahejie Formation in the Bozhong Sag, in the southeast by oil generated from the Eocene Shahejie and then Oligocene Dongying formations in the southwestern part of the Bozhong Sag and/or in the eastern part of the Shanan Sag, and in the southwest by oil generated from the Eocene Shahejie Formation in the western part of the Shanan Sag. The estimated migration distances range from less than 5 km to about 20 km. The compositional heterogeneity within fields and multiple-parameter comparisons between oils from nearby wells in different fields have proven to be a powerful tool to determine the in-filling histories of oil fields in cases where multiple source rock intervals and multiple generative kitchens exist.     

海南岛排浦现代白云岩若干特征及其岩化作用探讨

对我国首次发现的海南排浦现代白云岩的研究认为，该岩发育于早更新世湛江组滨海相细—粉砂层之中，通过交代作用形成具雾心亮边结构的菱面体自形晶，矿物上属钙过剩的含铁白云岩，其形成过程可分为二个阶段：准同生渗透回流白云岩化作用阶段；成岩混合水白云岩化作用阶段，而后一阶段可能延续至今。