Analysis of salt rock underground deposit failure probability in operation period based on response surface method

For the safety of salt rock underground deposit, uncertainties and their influences are considered, and failure probability during operation period is analyzed. Based on finite element model, equation of limit state surface is transformed into explicit equation by response surface method. Combined with Monte Carlo method, computation efficiency is improved. The deposit could be simulated as a series-parallel system. The element with highest failure probability is determined first, then failure mode and system reliability are computed. Taking Jintan underground gas deposit as an example, the analysis indicates that as storage pressure increases, failure probability of middle part of deposit decreases firstly, then increases gradually when storage pressure accumulates to a certain extent. The failure probabilities of upper part and underside of deposit increase as storage pressure increases. During operation period, controlled failure mode is shear failure of upper part and underside of deposit under high storage pressure. In conclusion, the storage pressure during operation period should be controlled strictly.     

黄河晋陕峡谷吉县段全新世古洪水平流沉积特征研究

鉴别古洪水沉积物是古洪水水文学研究中最基本的任务。古洪水沉积物特征的研究对于识别古洪水沉积以及利用古洪水沉积物来恢复古洪水的水位,流量和发生规律都有十分重要的意义。通过对黄河晋陕峡谷吉县段流域深入调查,在黄河中游峡谷发现具有典型的古洪水平流沉积夹层的全新世黄土古土壤剖面。利用地貌学和第四纪地质学、沉积学,进而通过磁化率、粒度分析深入揭示了古洪水沉积物与风成黄土堆积物之间的主要区别。     

北京王虎沟泥石流堆积物粒度参数分析

通过野外实地调查与室内实验相结合的方法,对王虎沟泥石流堆积物的粒度组成进行研究分析,采用平均粒径、分选系数、偏度、峰度等粒度参数分析了北京王虎沟堆积物特征。研究表明:颗粒平均粒径在上、中和下游表现为大—小—大,整个流域颗粒的分选均较差,上游和中游堆积区颗粒粒径偏度比下游更趋于对称;上中下游峰度值表现为大—小—大。通过对当地泥石流堆积物颗粒参数的分析,得出:此流域如遇暴雨极易发生泥石流灾害,会对当地人民群众的生产生活带来重要影响。     

沙金矿废弃矿区林业复垦树种选择

沙金矿废弃矿区，由于森林植被被破坏，水土流失严重，形成矿区荒漠化。本提出选择沙棘树种，作为林业复垦的选择树种。通过实践，收到理想效果。     

泥沙沉积与围垦对洞庭湖生态系统服务功能的影响

研究泥沙沉积和围垦对洞庭湖生态系统部分服务功能的影响结果表明,泥沙、围垦、湿地三者既互为条件,又互为因果关系,这种因果循环关系在湖泊生态系统中产生了泥沙淤积湿地浮涨钉螺孽生、害鼠繁殖、土地沙化,泥沙沉积湿地围垦生物资源量减少,泥沙沉积加围垦调蓄功能减弱洪涝频繁、水体污染、航道阻塞等一系列连锁反应,且很大程度上削弱或损害了湖泊服务功能,进而降低了部分服务功能的价值,即水产和饲草资源损失价值32 .1亿元,蓄水与供水功能损失价值1.5 3亿元,调蓄洪水与生物多样性损失价值4 1.92亿元,生态环境与航运功能损失价值74 .76亿元     

农村合作金融的国际比较分析以及对中国的启示

农村合作金融是农村金融系统的重要组成部分，可以成为农村经济发展的重要助推器。尽管在发达国家，商业银行的发展已经非常的成熟，但合作金融组织在这些国家尤其是农村仍然有其存在的必要性和合理性。本文以美国、德国、法国和日本作为研究对象，采用规范研究和实证研究相结合，理论分析与实际案例相结合的研究方法，综合分析这些发达国家农村合作金融组织的组织架构和运作特点，进行由点到面、由局部到全局的逻辑推理，最终提出中国农村信用社的改革路径，即“官退民进”；多元化经营战略；建立存款保险制度和完善相关法律法规等。     

华东某铀矿区稻米中Cr元素含量及其空间分布特征研究

利用等离子体质谱仪测定了某铀矿区周边稻米中重金属元素Cr的含量,重点对铀矿区稻米中的Cr元素含量及其空间分布特征进行了研究.结果表明,铀矿区内67.80％的稻米样品Cr含量超过国家标准（GB 2762-2005）;已经对环境造成了危害.铀矿区内稻米中Cr含量变化范围是0.37 ～ 13.20 mg/kg,平均含量为2.08 mg/kg.道路沿线区域、尾矿堆积区、水冶厂和矿床开采区下游及周边区域内稻米中Cr元素含量明显高于上游地区或远离上述区域的其他地区.矿床开采产生的废水与废渣、水冶厂的废液渗漏、尾矿露天堆积以及矿石运输过程中的矿渣洒落等原因可能是导致Cr元素随地表径流发生迁移进入稻田,从而使矿区稻米中Cr的含量较高的重要因素.     

Temporal (1958–1993) and spatial patterns of land use changes in Haut-Saint-Laurent (Quebec, Canada) and their relation to landscape physical attributes

In the last few years, landscape researchers have sought to understand temporal and spatial patterns of landscape changes in order to develop comprehensive models of land cover dynamics. To do so, most studies have used similar methods to quantify structural patterns, usually by comparing various landscape structural indices through time. Whereas the necessity for complementary approaches which might provide insights into landscape dynamics at some finer scale relevant to local managers has been expressed, few studies have proposed alternative methodologies. Moreover, the important relationship between the physical constraints of the landscape and land use dynamics has been seldom emphasized. Here we propose a methodological outline which was applied to the study of a rural landscape of Southern Quebec, Canada, to detect spatial and temporal (1958 to 1993) patterns of land cover changes at field, patch and landscape level. We then relate these patterns to the underlying physical structure of landscape elements using GIS and canonical correspondence analyses. We use the different geomorphological deposit types as stable discriminant factors which may constrain land use.Canonical correspondence analyses showed relations of land use and land use changes to the physical attributes of the landscape elements, whereas spatial analyses revealed very dynamic patterns at finer spatial and temporal scales. They highlighted the fact that not only the physical attributes of the landscape elements but also their spatial configuration were important determinants of land use dynamics in this area. Thus more land use changes occurred at the boundary between geomorphological deposit types than in any other locations. This trend is apparent for specific small-size changes (e.g. forest to crop), but not for the large-size ones (e.g. abandoned land to forest). Although land use changes are triggered by socioeconomic forces in this area, these changes are nevertheless constrained by the underlying physical landscape structure. A thorough comprehension of historical changes will enhance our capability to predict future landscape dynamics and devise more effective landscape management strategies.     

表面活性剂TX-10 对溶液表面张力及水稻植株持液量的影响

以生物染料丽春红-G作指示剂,采用称重法和比色法测定了水稻叶片持液量和丽春红-G的回收率。结果表明:水稻叶片对清水的持留量为0.05 mg/cm2,表面活性剂TX-10能降低清水的表面张力,增加其在水稻叶片上的持留量;与用清水配制的丽春红-G溶液喷洒,丽春红-G在水稻植株上的沉积率(29.83%)相比,用TX-10 60mg/L溶液配制的丽春红-G溶液喷洒,丽春红-G在植株上的沉积率显著提高(120.32%)。     

泾河下游全新世古洪水滞流沉积物研究

通过对泾河流域广泛的野外考察,在泾河下游高陵县段发现了典型的全新世古洪水滞流沉积剖面,系统地进行采集样品和粒度成分、磁化率、烧失量、吸湿水含量等多指标分析。从沉积学角度将古洪水滞流沉积物与全新世风成黄土和土壤进行对比,证明了该剖面所夹古洪水滞流沉积物的性质为细砂质粉砂,属于河流洪水悬移质泥砂沉积物。根据地层结构及与流域内其它剖面的对比,结合OSL测年数据,确定泾河在全新世中期4200~4000 a B.P.发生了第1期古洪水事件,在全新世晚期3200~2800 a B.P.发生了第2期洪水事件。这些古洪水事件都发生在全球性气候突变转折时期,表明在这些时期气候极端恶化,变率增大,洪水和干旱事件皆有发生。该研究对于泾河防洪减灾、水资源开发利用,对于揭示水文系统对于全球变化的响应规律,具有重要的科学意义。