青海丁叉叉山地区金红石矿床地质特征及找矿前景

丁叉叉山地区金红石矿床位于柴北缘成矿带东端,为近年新发现的大型金红石矿床。矿床产于古元古界金水口群地层榴辉岩体中,严格受榴辉岩体的控制。呈条带状、透镜状产出,近东西向展布。成因类型属榴辉岩型金红石矿床,成矿时期为加里东期。在总结区内矿床地质特征的基础上,进而与国内苏鲁榴辉岩金红石矿床、省内鱼卡榴辉岩型金红石矿床等典型矿床对比分析,研究表明:区内榴辉岩成矿条件有利,保存条件良好,具有较好的找矿前景。     

大柴旦低品位硼矿富集研究

研究了一种提高青海大柴旦地区低品位硼矿品位的浮选方法。采用Y-ZS为调整剂、B-HW为捕收剂,经两次粗选、两次精选、一次扫选流程,可获得较好的浮选分离指标,可使硼矿B2O3品位由7.36%提高到17.21%,收率达到77.25%。     

柴东欧南凹陷上石炭统克鲁克组构造背景、物质来源及沉积环境

柴达木盆地东部（简称柴东）欧南凹陷上石炭统克鲁克组获得油气发现,但该层段的构造背景、物质来源与沉积环境动态演化过程研究依然较薄弱。通过对欧南凹陷东北侧柏树沟露头上石炭统克鲁克组（C₂k）细粒沉积岩开展元素地球化学研究,结果表明,欧南凹陷在C₂k沉积期是阿尼玛卿洋壳向北俯冲控制的主动大陆边缘活动背景下弧后裂陷盆地的组成部分,南部的柴北缘加里东构造带向其提供酸性岩浆岩为主要母岩的陆源碎屑,北部的宗务隆海槽由于枕状玄武岩喷发和低温蚀变产生溶解硅,经海底洋流上升引发硅质浮游生物群落的繁盛而沉积生物硅。C₂k沉积期处于全球范围晚古生代冰期的第Ⅲ期事件,共识别出3期次间冰期（升温事件A、B和C）。古气候温度升高引发冰川型海侵,水体随之加深,缺氧程度增强,海水的回灌和升温蒸发作用使盐度升高而咸化;其中升温B期的温度升高强度和海平面上升幅度均强于升温A期和C期,对应于C₂k最大海泛面,古水体达到弱还原状态,宗务隆海槽方向以硅质生物为代表的海洋低等水生生物供给数量增多,其他时段主要受柴北缘构造带方向陆源有机质的影响。以上研究结果及认识为探索柴达木盆地石炭纪构造—沉积—古地理演化过程和有机质富集机制提供了依据。     

青海省盐湖集团供水二期水源地数值模拟

针对山前冲洪积扇傍河水源地共有的水文地质条件,建立地下水流数学模型,采用Visual Modflow软件,选取极富水地段进行地下水数值模拟研究。在综合分析格尔木河冲洪积扇水文地质条件基础上,确定三维边界条件,建立水文地质条件概念模型及数学模型,通过对地下水梯度场、降速场与实测资料的识别与验证,模拟的流场形态与观测值及地下水动态拟合度较高,符合研究区水文地质条件。模型对10年内丰、平、枯水期降水频率下的开采方案结果及水均衡状态进行了预测,结果表明,拟建水源地所需的可开采水量(新增13.2万m3/d)基本可行。     

基于RS与GIS的典型地区土地利用/覆盖变化研究——以三江源生态环境重点保护区玛多县为例

典型地区和脆弱区的土地利用/覆盖变化是区域性研究的重要内容。三江源地区是国家级自然保护区,生态系统异常敏感和脆弱。以典型地区玛多县为案例,基于RS和GIS技术,系统研究了该地区土地利用/覆盖变化及其对景观格局的影响,探讨了生态环境演化过程,可为更广泛的区域性综合提供基础。研究发现:①10 a间,该地区湿地、水体和天然草地明显减少,湿地减少比例达到36.63%,大于6 hm²的湖泊减少近半数;沙地,裸地和盐碱地等明显增加,草地退化、沙漠化严重;②天然草地、裸地、沙地、水体、湿地和盐碱地之间的类型转化较为明显,且与水资源又有密切的关系。③多样性、均匀性指数和景观异质程度提高,土地趋于多样化和均匀化;裸地、沙地优势度增加,湿地、水体和天然草地优势度减少;整体破碎化程度呈缓慢减少趋势,而湿地、沙地破碎度增加。④综合土地利用动态度为0.98,天然草地、裸地、湿地、沙地动态面积变化较大。⑤研究区的土地利用/覆盖变化将深刻影响该地区的生态过程,同时还将影响三江源地区的水源涵养和供给。     

基于专家系统法的异形件最小包络矩形求解

异形件布局问题广泛存在于社会各领域.目前,直接处理异形件布局问题的算法设计难度和计算量较大,而矩形件布局已有一些成熟算法.因此,将异形件转化为矩形件后处理布局能简化问题,并保证良好布局效果.本文基于专家系统法处理异形件,使其转换为易解决布局的包络矩形.     

Effect of spatial variation on areal evapotranspiration simulation in Haibei,Tibet plateau,China

Quantification of areal evapotranspiration from remote sensing data requires the determination of surface energy balance components with support of field observations. Much attention should be given to spatial resolution sensitivity to the physics of surface heterogeneity. Using the Priestley–Taylor model, we generated evapotranspiration maps at several spatial resolutions for a heterogeneous area at Haibei, and validated the evapotranspiration maps with the flux tower data. The results suggested that the mean values for all evapotranspiration maps were quite similar but their standard deviations decreased with the coarsening of spatial resolution. When the resolution transcended about 480 m, the standard deviations drastically decreased, indicating a loss of spatial structure information of the original resolution evapotranspiration map. The absolute values of relative errors of the points for evapotranspiration maps showed a fluctuant trend as spatial resolution of input parameter data layers coarsening, and the absolute value of relative errors reached minimum when pixel size of map matched up to measuring scale of eddy covariance system. Finally, based on the analyses of the semi‐variogram of the original resolution evapotranspiration map and the shapes of spatial autocorrelation indices of Moran and Geary for evapotranspiration maps at different resolutions, an appropriate resolution was suggested for the areal evapotranspiration simulation in this study area.     

青海水利信息资源整合与共享思路的探讨

随着青海水利信息化的发展,水利信息资源整合与共享的需求突出,结合青海水利信息资源整合与共享的要求,提出开展顶层设计,推进水利信息化基础设施、信息资源、业务应用系统、建管体系整合与共享的思路,实现青海水利信息资源整合与共享目标。     

青海省农民对灌溉水价承受能力实证研究—以都兰、贵德、大通三县为例

选取青海省柴达木盆地都兰县、黄河干流贵德县、湟水流域大通回族土族自治县为研究区域，在对三县部分灌区的农户问卷调查的基础上，从经济承受能力和心理承受能力进行了农民对灌溉水价承受能力的典型研究。结果表明青海省农民对灌溉水价经济承受能力有限，但现状水价还有一定的提升空间；灌溉水价心理承受能力严重滞后于经济承受能力，受真实水价的高低影响很大。最后提出了提高农民对水价承受能力的主要对策。     

Theoretical studies on the interaction of modified pyrimidines and purines with purine riboswitch

Recent experimental study [S.D. Gilbert, S.J. Mediatore, R.T. Batey, Modified pyrimidine specifically bind the purine riboswitch, J. Am. Chem. Soc. 128 (2006) 14214–14215] demonstrated that the purine riboswitch could specifically bind some ligands other than purines such as amino-pyrimidines, and the authors proposed that the five-membered ring of purine was not required for recognition. To get insight into the interaction details, we used molecular docking method to investigate the interactions of a mutant form of guanine riboswitch with a series of amino-purines, amino-pyrimidines and imidazole derivatives, and employed molecular simulation method to study the dynamic behavior of the selected complexes. The calculation results reveal that (1) all the amino-purines and amino-pyrimidines bind in a same cavity composed of four nucleobases including U22, U47, U51 and U74, which is consistent with the experimental results, while the two imidazole derivatives adopt other binding modes; (2) the purines are engulfed within three-way junction motifs, but most pyrimidines only form two-way junctions with the riboswitch; (3) the number and position of amino substituents could seriously affect the binding of pyrimidines. As riboswitches are potentially excellent candidates for antibiotic therapeutics, these findings may be useful for understanding the range of compounds that riboswitch can specifically recognize.