鹤壁市单日降水量极值估算

利用耿贝尔(Gumber)极值分布原理,对鹤壁市1965-2004年最大日降水量进行降水分布拟合,估算预报时段内可能出现的最大日降水量,得出50 a、80 a鹤壁市可能出现的最大日降水量分别为278.7 mm和301.9 mm;利用二次指数平滑法,得到鹤壁市最大日降水量年际变化总体上呈线性减少趋势.统计结果显示:鹤壁市最大日降水量有峰值增大、谷值减小的趋势,说明在未来一定时期,极端最大日降水量发生的可能性不断增加;最大日降水量集中出现在7-8月份,有明显的季节特征.     

杭州市雷电活动特征及雷电灾害区划

利用杭州市1966—2005年雷暴日资料和2008—2009年闪电定位资料,运用ArcGIS空间分析技术结合数理统计方法,分析杭州市雷电活动时空分布特征,并采用地闪密度空间分布与最大地闪强度空间分布的叠置作为雷电风险的主要评价指标,得到杭州市雷电灾害致灾危险性区划。分析结果表明,在时间分布上,杭州市雷暴天气多发生在夏季和午后时段;在空间分布上,杭州市地闪密度较大地区多集中在山脉向阳坡、迎风坡以及大面积水域向陆地过渡的区域。杭州市雷电灾害风险高值区主要集中在上城区、江干区、滨江区、西湖区西部以及淳安县西南部、富阳市大部、余杭区西部、萧山区中部地区。雷电风险高值区主要集中在人口稠密区、工业集聚区、湖边、江边等,这些都可能与气温、空气湿度、地形地貌、建筑物密集密切相关。     

科技地缘政治：从现实到理论——关于地理学加强科技地缘政治研究的思考

世界在科技全球化、科技变革和大国科技博弈进程中正步入科技地缘政治时代。全球科技竞合是科技地缘政治时代的主旋律,也是大国博弈的主导形式。文章首先从全球科技竞合现实出发,明确了中国在科技地缘政治时代修正或重构国家科技地缘战略的重要性,认为应对国际国内形势变化,保障国家科技安全,中国需要加强科技地缘政治研究。其次,从时代变迁和地缘政治理论演进的视角阐释了科技地缘政治研究亟需建构新的理论体系和分析范式的原因。在此基础上,系统梳理了地理学、政治学和科技管理领域关于科技地缘政治研究的主要进展和存在的问题,认为：地理学领域的科技地缘政治探索虽详尽地揭示了全球科技竞合的时空特征,但并未从全球科技竞合的表象透视国家科技权力争夺的本质;政治学领域的科技地缘政治探索虽详细追溯了科技进步与地缘政治理论思潮演进和地缘政治格局演变的关系,但其剥离空间的抽象思维无法解释国家围绕一定地理空间进行博弈的现实;科技管理学领域的科技地缘政治探索虽进行了系统的全球科技体系演化与治理的研究,但其研究的立足点忽视了大国科技竞合的本质。鉴于此,提出了未来中国地理学在科技地缘政治研究的主要努力方向。     

Compositional heterogeneity of crude oil and its origin in the Linnan subsag, Linyi County, Shandong Province

The Linnan subsag is the main oil producer of the Linpan oil zone. Based on the oil group composition, gas chromatography data and biomarker analysis, it was indicated that crude oils from different oilfields varied greatly in group composition and showed obvious heterogeneities in the aspects of precursor type, crude oil maturity and hydrocarbon depositional environment. According to the characteristics of source rocks, three oil populations can be distinguished, i.e., the southern, northern and transitional oil populations. Furthermore, on the basis of post-reservoir reworking processes, the medium conditions of hydrocarbon-generating environment and differences in maturity, six oil families and twelve sub-families were distinquished. An integrated study suggested that the factors leading to such heterogeneities in crude oil composition mainly include different source rocks, multi-stage oil/gas charging, geo-chromatographic effects during oil/gas migration, reservoir heterogeneities and various post-reservoir secondary alterations.     

湘南铜山岭铜多金属矿床成矿物质来源的 S、Pb、C同位素约束

铜山岭铜多金属矿床是湘南W、Sn、Pb、Zn、Cu多金属矿集区的代表性矿床,本文对其不同类型岩石和矿石矿物进行了S、Pb、C同位素组成对比研究。矿石硫化物的δ34 S值变化范围为-1.9‰~5.7‰,平均值为2.6‰,硫主要来源于硫同位素组成均一化的岩浆。硫化物硫同位素平衡温度表明,矿床主要成矿温度为134~339℃。矿石铅的206 Pb/204 Pb、207 Pb/204 Pb、208 Pb/204 Pb比值分别为18.256~18.856、15.726~15.877、38.352~39.430;岩体岩石铅的206Pb/204Pb、207Pb/204Pb、208Pb/204Pb比值分别为18.617~18.805、15.721~15.786、38.923~39.073;两者铅同位素组成相同,都主要为上地壳铅,是由同一岩浆体系分异形成,可能来源于古老基底岩石。不同类型岩石、方解石矿物的δ13 CPDB值为-9.88‰~1.32‰,δ18 OSMOW值为11.67‰~17.68‰,从矽卡岩矿体到距岩体稍远的围岩地层,方解石矿物的δ13 CPDB、δ18 OSMOW值逐渐增大,成矿流体中的碳早期可能主要来源于岩浆,在成矿过程中有部分碳酸盐岩地层碳的加入。铜山岭矿床成矿物质主要来源于岩浆,赋矿地层对矿床成矿物质来源作用不显著,仅提供了少量成矿物质。     

Changes in soil quality in the critical area of desertification surrounding the Ejina Oasis,Northern China

The critical area around an oasis where desertification occurs determines the ecological security and stability of the oasis. In this study, the soil quality in the critical area of desertification surrounding the Ejina Oasis was evaluated by using a soil quality index (SQI). The soil surface moisture content was related to vegetation cover; it remained high to a distance of 600 m from the oasis, decreased at distances of 600 to 1,700 m, and then gradually increased to a distance of 1,900 m. The sand content and soil bulk density gradually decreased to a distance of 300 m from the oasis; however, the silt and clay contents, soil pH, soil organic matter (SOM), and total and available nutrients increased away from the oasis. From 300 to 1,900 m, the sand content and soil bulk density increased; however, values of other soil properties decreased. Thus, a distance of 300 m from the edge of the oasis represents an obvious demarcation point for soil properties. SOM and the clay content were the key factors that determined soil quality. SQI increased from 0.284 at the edge of the oasis to 0.793 at 300 m, decreased to 0.262 at 1,400 m, and then decreased further to 0.142 at 1,900 m. SQI was lowest at distances of 1,400–1,900 m. The area beyond 300 m from the oasis was most vulnerable to desertification, and is thus the area where desertification control measures should be strengthened.     

库车坳陷中生代海侵事件对有机质的影响

对库车河剖面三叠侏罗系重要生烃组段进行了有机质生物标志化合物及单体烃同位素研究,研究结果表明,海侵层位与非海侵层位在生物组成和生标特征等方面明显不同,海侵带来了不同的生物体,使有机质类型发生了改变。在生物标志化合物参数方面表现为Ｐｒ／Ｐｈ小于１,甾烷含量丰富,甾烷中Ｃ_２７化合物丰度与Ｃ_２９相当,三环萜烷有Ｃ_２１＜Ｃ_２３＞Ｃ_２４的分布特点,单体烃同位素表现出富集轻碳同位素的特点。中生代海侵事件对塔北隆起区及库车拗陷油气资源具有重要的意义。     

湖北古城锰矿的沉淀形式及其古环境意义

古城锰矿是扬子地台北缘典型的“大塘坡”式锰矿,赋存于南华系大塘坡组含锰黑色岩系中,含锰矿物主要为菱锰矿.古城锰矿稀土总量高、类似现代海底铁锰结核的“帽式”稀土元素配分模式和Ce的正异常等地球化学指标指示古城锰矿Mn是以锰氧化物或氢氧化物形式沉淀,锰碳酸盐是后期转化而成.Fe/Mn比值低,较低的V、U含量和中等程度的Mo富集以及氧化还原敏感元素对Th/U、V/Cr、V/(V+Ni)比值等地球化学指标指示古城锰矿沉积环境为一种氧化一次氧化的状态,与锰是以锰氧化物或氢氧化物形式沉淀的结论一致.综合认为,古城锰矿成矿机制包括沉淀和转化两个过程,在氧化还原分层的海洋系统中,Mn在上部氧化性的水体中以氧化物或氢氧化物形式沉淀,之后下沉被掩埋在缺氧带之下,在成岩过程中和有机物质相互作用,锰氧化物或氢氧化物被还原释放出的Mn2+和有机碳被氧化释放出的CO32-结合形成锰碳酸盐,其转化可以方程2MnO2+CH2O+HCO3-=2MnCO3+H2O+OH-简单表示.     

冬春亚洲大气环流与华北中部夏季降水的相关分析

利用1957~2002年的NCEP/NCAR 500 hPa再分析资料以及同期华北地区夏季降水资料,分析了华北中部夏季降水与前期环流的关系。结果表明:夏季华北中部降水的多少与冬季东亚槽强弱、春季巴尔喀什湖到贝加尔湖的蒙古高原地区高度场呈显著相关。20世纪80年代中期以前冬季东亚槽偏强、春季蒙古高原地区高度值偏低;80年代中期之后冬季东亚槽开始转弱、春季蒙古高原地区高度值偏高。这与华北夏季降水的演变趋势相对应。说明冬季东亚槽的减弱以及春季蒙古高原地区高度值偏高是近年来华北夏季降水减少的原因之一。冬季东亚槽强对应夏季西太平洋副高在日本海地区高度呈偏强趋势,有利华北中部夏季降水偏多;春季蒙古高原地区高度值偏高有利于华北夏季出现西高东低形势,华北中部夏季降水易偏少。     

The separation mechanism and application of a tapered diameter separation bed

Research on recycling waste printed circuit boards is at the forefront of preventing environmental pollution and finding ways to recycle resources. A wet process for reclaiming metals from printed circuit boards applying a tapered diameter separation bed is described, and the separation mechanism of the device is proposed. The motion of a particle in the tapered diameter fluid flow field and particle separation within this field were studied. As the material passes through the fluid field, along with the water, differences in particle density, granularity, and shape cause particles to follow at different trajectories. A tapered diameter separation bed was used to process 1?C0.074?mm-sized crushed material from discarded printed circuit boards. The separation efficiency of 91.77?% and the recovery rate of 95.79?% for recovered metal were achieved with a discharge water flow rate of 4.5m³/h, a material feed rate of 300?g/min, and an obliquity of 30°. For ?0.074?mm printed circuit boards, the metal recovery is 93.42?% and the separation efficiency is 77.63?% when the water discharge is 2?m³/h, the obliquity is 35o, and the material feed rate is 450?g/min. The superfine products in a size range of ?0.074?mm can be recovered effectively under suitable operating condition using the tapered diameter separation bed. It indicates that the lower separation limit of the tapered diameter separation bed can be close to zero. The technique will prevent environmental pollution from waste printed circuit boards and allow efficient recovery.