泰山地区太古宙杂岩体的地球化学特征

本文根据野外地质特征,岩石类型之间的一些变化关系和岩石化学、地球化学特征,将泰山地区太古宙杂岩体划分为两大成因系列,即深熔系列(主要指一系列花岗岩)和幔源系列(主要指一系列基性岩和中性岩).     

岱海地区近400年来的"尘暴"事件——来自岱海沉积物粒度的证据

根据高分辨率的岱海沉积物粒度分布的中值粒径和粗颗粒含量,结合区域降水、历史记载资料,重建了内蒙古岱海地区近４００年来发生的尘暴事件。结果表明,尘暴事件是受冬、夏季风的相对强弱制约的,大量尘暴事件频发于小冰期干冷的气候条件下,表现为中值粒径大,粗颗粒含量高,在转暖的现代气候下,尘暴事件很少,中值粒径也随之降低,但是近十几年尘暴事件又呈上升趋势,部分可能与人类活动造成的土地荒漠化有关。     

川东地区嘉陵江组四段膏盐岩分布的沉积环境分析

四川盆地东部地区嘉陵江组嘉四段沉积环境是局限海台地蒸发岩相,水体封闭,有利成盐。以川东地区油气勘探的500余口实际钻井资料为基础,通过岩性微相的研究,探讨川东地区的古地貌特征,寻找成盐的微环境因素,有助于从区域上预测盐类的分布。T1j4盐湖主要分布在蒸发岩沉积中心——膏盆相,但位于膏盆相的周缘地带和膏盆内部堤坝周围,少部分分布在膏盆边缘相,区域上则主要分布在宣汉、达州、万县、云阳、垫江及渠县等地区,有一定的继承性。     

Contribution to diffuse gamma-rays in the Galactic Centre region from unresolved millisecond pulsars

Diffuse gamma-rays in the Galactic Centre region have been studied. We propose that there exists a population of millisecond pulsars in the Galactic Centre, which emit GeV gamma-rays through synchrotron-curvature radiation as predicted by outer gap models. These GeV gamma-rays from unresolved millisecond pulsars probably contribute to the diffuse gamma-ray spectrum detected by EGRET which displays a break at a few GeV. We have used a Monte Carlo method to obtain simulated samples of millisecond pulsars in the Galactic Centre region covered by EGRET  (∼ 15)  according to the different period and magnetic field distributions from observed millisecond pulsars in the Galactic field and globular clusters, and superposed their synchrotron-curvature spectra to derive the total GeV flux. Our simulated results suggest that there probably exist about 6000 unresolved millisecond pulsars in the region of angular resolution of EGRET, the emissions of which could contribute significantly to the observed diffuse gamma-rays in the Galactic Centre.     

Al掺杂对尖晶石型LiMn2O4结构及循环性能的影响

用柠檬酸作为螯合物的载体,采用溶胶-凝胶法合成了Al3+掺杂的锂离子电池正极材料LiAlxMn2-xO4,并用XRD、SEM等多种测试手段研究了不同掺杂铝量对粉体形貌、晶体结构的影响。结果表明,800℃烧结可获得单一尖晶石结构的物相。随着Al3+掺入量的增加,LiAlxMn2-xO4的晶格常数变小,晶格更趋于完整,有利于抑制因锂的反复脱嵌而造成结构的破坏。实验表明,当掺Al量为0.05时,首次放电容量为103.8 mAh/g,25次循环后容量还有100.6 mAh/g,容量衰减仅为3.08%。该正极材料具备高的容量和优异的循环性能。     

新疆绿洲当代人地关系紧张情势与缓解途径

讨论了目前新疆人地关系紧张的情势;分析了造成新疆绿洲目前人地关系紧张的主要原因。认为环境先天脆弱、水资源总量有限且分布不均、气候的干暖化等是产生目前新疆人地关系紧张的生态环境前提;快速增长的人口及其不断增长的需求和过激的经济发展政策对环境产生了极大的压力;资源滥用、管理机制不健全、相关法律法规执法不严以及有偿使用制度不完善是造成目前区域人地关系紧张的主要原因。最后讨论了缓解当前新疆人地关系紧张矛盾的途径。     

Comparison of Kuqa foreland basin with Persian Gulf Basin in salt tectonics

Compared Kuqa foreland basin with Persian Gulf Basin in development of salt layers, salt tectonics, and the relation between salt tectonics and hydrocarbon, it is concluded that the salt diapirs are relative to hydrocarbon. Searching salt diapirs and related traps in Kuqa foreland basin is important. The forming mechanism of salt tectonic in Kuqa foreland basin is different from that of Hormuz Series, but similar to that of Lower Fars Series/Gachsaran Formation. Inspired by the role of salt tectonics of Lower Fars Series/Gachsaran Formation in hydrocarbon accumulation, the authors considered that the exploration below salt layer should be enforced, and the traps below salt layer in the southern part of the Kuqa foreland basin would be found where salt layer is thicker. On the contrary, the traps should be found both above and below the salt layer in front of the northern mountain where salt layer is thin. The Triassic and Jurassic source rocks are rich in this area with great exploration prospective.     

共和盆地黏土矿物与孢粉记录的末次冰消期以来的气候环境相位差

在青藏高原北缘共和盆地达连海钻取了40.92 m沉积柱,其¹⁴C年代有10个控制点,底部年龄最大值为14.5 cal ka BP,沉积柱为末次冰消期以来的湖泊沉积物。在沉积柱中按20 cm/70 a分辨率选出200个样品进行了黏土矿物、粒度、碳酸盐、沉积速率等非生物指标与生物指标的孢粉等多项指标的综合分析。结果表明：末次冰消期以来,达连海沉积柱中非生物指标与生物指标反映的气候和环境变化阶段的显著性不同,反映的气候环境的变化阶段也不尽一致,出现气候环境的相位差。冰消期黏土矿物非生物指标与孢粉生物指标有约1.0~1.2 ka的相位差;早、中全新世黏土矿物反映的气候变化时段较孢粉指标指示的时段滞后约1.0 ka;在晚全新世黏土矿物反映的气候变化较孢粉滞后约0.1 ka。造成黏土矿物和孢粉反映气候环境相位差的原因是孢粉和黏土矿物对气候响应的差异性、黏土矿物和孢粉搬运方式的不同、气候条件及其转换、地貌等多因素的综合影响。     

中国GIS产业发展问题与对策研究

虽然中国GIS产业比十多年前有了显著的进步,但是问题依然很多,集中表现为:GIS产业规模小、应用广度和深度不够;GIS产业服务体系不健全;GIS教育不能适应产业发展的需要;GIS标准化工作滞后。中国GIS产业的发展壮大,不仅需要地理信息技术的进步,GIS软件产品的创新,而且要建立相应的产业服务体系,加快GIS新型人才的培养。中国GIS产业发展过程中的一系列问题是环环相扣的,我们不应该就事论事、画地为牢,而是要“大处着眼、小处着手”,加强当前比较薄弱的产业环节。随着国家信息化进程的推进,特别是电子政务建设的兴起,中国GIS产业面临许多新的机遇。正视目前存在的问题,及时采取适宜的对策,中国GIS产业必将蓬勃发展。     

A Two—Temperature Supernova Fallback Disk Model for Anomalous X—ray Pulsars

We present a case study of the relevance of the radially pulsational instability of a two-temperature accretion disk around a neutron star to anomalous X-ray pulsars (AXPs). Our estimates are based on the approximation that such a neutron star disk with mass in the range of 10^-6-10^-5M⊙ is formed by supernova fallback. We derive several peculiar properties of the accretion disk instability: a narrow interval of X-ray pulse periods; lower X-ray luminosities; a period derivative and an evolution time scale. All these results are in good agreement with the observations of the AXPs.