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1.
典型岩溶流域土地整理的生态评价——以云南小江流域为例 总被引：2，自引：0，他引：2
以云南小江典型岩溶流域为例,在GIS支持下,通过选择评价因子和建立评价模型对岩溶区的土地整理进行了生态评价。结果表明: 流域生态评价分值较高的土地面积较少,而生态评价分值较低的土地面积较大。分值在80～ 100的土地整理主要任务是在保护生态环境质量和耕地数量的前提下,加快流域经济结构的调整,提高土地利用的经济效益;分值在70～ 80的土地整理主要任务是耕地数量保护和质量保护并重,提高土地的生产能力,提高经济效益,同时防止水土流失及化肥、农药施用对地下水造成的非点源污染; 分值在60～ 70的土地整理主要任务是着重于生态环境的保护和重建以及立体农业的综合开发; 分值在60以下的土地整理主要任务是土地石漠化的治理。 相似文献
2.
地勘单位要吸引和留住人才,就要在事业、感情、待遇留人上下功夫.即营造鼓励人才干成事业、帮助人才干好事业、创造施展才华的社会氛围和环境;用来自领导的关心爱护之情,同事的团结友爱之情来拴住人心;为人才提供与其创新能力和贡献相适应的物质待遇,使人才充分享有实现自身价值的自豪感、贡献社会的成就感、得到社会承认的荣誉感. 相似文献
3.
Landslide risk: some issues that determine societal acceptance 总被引：2，自引：1，他引：1
This paper illustrates approaches to landslide risk acceptance in various parts of the world in the context of the willingness to accept that risk, the willingness to pay to reduce the risk, and the willingness to alter the environment in the process. These factors are interlinked using the ternary ??willingness diagram?? which is also used to demonstrate how such willingness may change over time and to compare a range of generic approaches to landslide remediation as well as different conceptual approaches to landslide risk management. The willingness construct is intended to provide a readily understood framework for infrastructure owners and operators, amongst others, to understand how their approach to risk management compares with those in other regions, countries and contexts. Issues relevant to the response of society and groups of individuals to landslide risk, its acceptance and management include cultural factors, regulation and planning, budgetary constraints, vehicular vulnerability, and the often limited size of the event footprint compared to the vulnerability shadow that is cast are also discussed. 相似文献
4.
本文据东海五口探井的559个碎屑矿物样资料,用主要重矿物的含量及其组合特征编绘了含量变化图,试图进行分层比较。位于西湖凹陷的平湖一井和玉泉1井重矿组合特征可比性较好;龙井2井三潭组以下与上两井缺少可比特点;灵峰1井除东海群外,其余地层与上列3井相比,差异是大的。 相似文献
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6.
Based on the questionnaire survey, this paper analyzes China’s public perception of climate change in terms of several influence factors and some empirical findings are obtained. We find that some respondents are willing to take individual actions to address climate change, and they pay more attention to climate change or approve that climate change does harm to residents and society; meanwhile, they tend to have confidence in the government to deal with climate change or believe that fiscal and taxation policies are the effective policy measures. However, there are also other respondents unwilling to take actions and argue that climate change proves the natural consequences. Thus, in order to motivate the public to take actions, the paper suggests that the government should widespreadly disseminate relevant knowledge about climate change to the public and guide the work to address climate change and adopt proper fiscal and taxation policies. 相似文献
7.
针对碳酸盐岩薄储层气藏预测受制于地震分辨率,用常规反演方法往往很难解决薄储层气藏预测问题,通过参数加权综合法研究,从地震信息中提取薄储层5大类共计35种地震波场特征参数,通过Karhune—Loeve变换压缩降维,采用广义线性分类判别及加权综合处理,可获得能反映薄储层气藏特征的综合参数,较好地解决薄储层气藏预测的难题。在实际推广应用中也见到了良好的效果．如四川同福场构造嘉陵江组嘉二^1气藏为一典型碳酸盐岩薄储层气藏,储层纵向上厚度较薄,一般有效储层厚度多为1m～3m,曾采用地震速度反演方法做过多轮储层预测,但因储层测井差异性特征不明显以及储层太薄等因素,预测效果均不理想,而采用地震参数综合法则较好地解决了本区薄储层气藏的预测难题,预测符合率达到95．5％。 相似文献
8.
封闭体系有机质与有机碳氢氮恢复动力学研究 总被引：3，自引：0，他引：3
在封闭体系的条件下,对典型的Ⅰ、Ⅱ、Ⅲ型干酪根在热演化过程中的损失进行生烃动力学研究,获得了Ⅰ、Ⅱ、Ⅲ型干酪根的总量、有机碳、氢以及氮质量损失动力学参数。用Kinetics软件计算了封闭体系干酪根有机碳丰度、氢碳原子比和氮碳原子比的恢复系数。认为在对高成熟—过成熟干酪根进行生烃评价时,Ⅰ、Ⅲ型干酪根残余有机碳丰度需要进行恢复,而Ⅱ型干酪根残余有机碳丰度不需要恢复。三种类型干酪根的氢碳原子比均需要进行恢复。 相似文献
9.
Aquifer remediation for a contaminated site is complex, expensive, and long-term. Groundwater modelling is often used as a tool to evaluate remedial alternatives and to design a groundwater remediation system. Groundwater modelling can also be used as a useful process to identify aquifer characteristics and contaminant behaviour that are not realized prior to modelling, to help diagnose what happened and why it happened at contaminant sites. Three real-world modelling cases are presented to demonstrate how groundwater modelling is applied to help understand contamination problems and how valuable the improved understanding is to decision-making and/or to remedial design. 相似文献
10.
基岩裂隙水探寻是一项意义重大的研究课题,富水优势断裂的确定是其中的关键。文章详细论述了运用层次分析法寻找富水优势断裂并进行分级的实施方法。这一方法的实施可归纳为"两个前题条件,五个分析步骤,一个结果判断",两个前题条件为富水性功能分类和构建优势指标体系,五个分析步骤为构建层次分析结构模型、构造判断矩阵、层次单排序及其一致性检验、层次总排序、对象层权重总排序;一个结果判断为利用层次分析的结果进行断裂富水性分级,从而最终确定出富水优势断裂。此法为富水优势断裂的定量化评价提供了一种简洁、实用的新方法。 相似文献
11.
R. P. Bewick P. K. Kaiser W. F. Bawden N. Bahrani 《Rock Mechanics and Rock Engineering》2014,47(5):1647-1671
A particle-based distinct element method and its grain-based method are used to generate and simulate a synthetic specimen calibrated to the rupture characteristics of an intact (non-jointed) low-porosity brittle rock deformed in direct shear. The simulations are compared to the laboratory-generated ruptures and used to investigate rupture at various normal stress magnitudes. The fracturing processes leading to shear rupture zone creation and the rupture mechanism are found to be normal stress dependent (progressing from tensile splitting to shear rupture) and show partial confirmation of rupture zone creation in nature and in experiments from other materials. The normal stress dependent change is found to be due to the orientation of the major principal stress and local stress concentrations internal to the synthetic specimens being deformed. The normal stress dependent rupture creation process results in a change to the rupture zone’s geometry, shear stress versus horizontal displacement response, and thus ultimate strength. 相似文献
12.
"同一健康"概念是一种融合跨学科和跨行业资源的整体性健康研究与管理新方法,为医学地质创新发展提供了新视角.在全球性传染病防治引起人类社会空前重视的时代背景下,医学地质学需要研究在人类活动影响下,地球物质循环、生态系统韧性变化与疾病出现和传播模式的变化之间的成因联系,并面临三方面的科学挑战:（1）研究对人类和动物有害或有益的地球物质循环规律及其健康风险;（2）揭示与全球性疾病有关的地质环境因素和过程,探索减缓风险对策;（3）识别和评估新型污染物和病原体的分布、迁移与健康风险.为有效应对这些挑战,需要整合创新资源,倡导和支持"聚合"研究,推动多学科协作的医学地质调查计划,加强平台建设和人才培养. 相似文献
13.
《International Geology Review》2012,54(11):1042-1050
Minerals of the stibnite-antimonselite series, in close association with tiemannite, clausthalite, kullerudite, Se-bearing stibioluzonite, native gold, quartz, and barite, were discovered in Cambrian stratabound gold deposits at La'erma and Qiongmo, western Qinling, China. Based on S/(S + Se) ratios of microprobe analyses, the binary stibnite-antimonselite system is divided into four series: stibnite, Se-stibnite, S-antimonselite, and antimonselite. Micro-hardness of the stibnite series (Sb = 58.47 to 72.99 wt%, S = 11.86 to 28.76, and Se = 0.00 to 29.12) and the antimonselite series (Sb = 48.94 to 59.13 wt%, Se = 29.20 to 46.86, S = 1.99 to 11.43) is 101.26 and 103 kg/mm2, respectively. Representative reflectivities of the four series are (470 nm) Rg'= 42.62 to 47.62%, Rp' = 30.83 to 40.55%; (550 nm) Rg' = 41.84 to 46.75%, Rp'= 31.48 to 38.85%; (590 nm) Rg' = 42.25 to 46.63%, Rp' = 30.73 to 39.46%; (650 nm) Rg' = 43.30 to 46.48%, Rp' = 30.01 to 41.56%. Cell parameters obtained from two stibnite samples (containing 3 to 5% Se) are a = 1.1209 to 1.1212 nm, b = 1.1299 to 1.1303 nm, c = 0.3847 to 0.3849 nm; and those of S-antimonselite and antimonselite are a = 1.1591 to 1.1593 nm, b = 1.1724 to 1.1747 nm, and c = 0.3941 to 0.3984 nm. 相似文献
14.
A topical evaluation and discussion of data movement technologies for data-intensive scientific applications 总被引：1，自引：1，他引：0
Chris A. Mattmann Luca Cinquini Paul Zimdars Michael Joyce Shakeh Khudikyan 《Earth Science Informatics》2016,9(2):247-262
Transferring large volumes of information from one location to potentially many others that are geographically distributed and across varying networks is still prevalent in modern scientific data systems. This is despite the movement to push computation to the data and to reduce data movement needed to compute answers to challenging scientific problems, to disseminate information to the scientific community, and to acquire data for curation and enrichment. Because of this, it is imperative that decisions made regarding data movement systems and architectures be backed by both analytical rigor, and also by empirical evidence and measurement. The purpose of this study is to expand on the work performed by our research team over the last decade and to take a fresh look at the evaluation of multiple topical data transfer technologies in use cases derived from data-intensive scientific systems and applications in the areas of Earth science. We report on the evaluation of a set of data movement technologies against a set of empirically derived comparison dimensions. Based on this evaluation, we make recommendations towards the selection of appropriate data movement technologies in scientific applications and scenarios. 相似文献
15.
A. Torabian A. H. Hassani S. Moshirvaziri 《International Journal of Environmental Science and Technology》2004,1(2):103-107
In this research, physical, chemical and biological treatability of Tehran solid waste leachate was studied. Results indicate that the amount of COD for the fresh raw leachate of Tehran is equal to 66,608 mg/l. The leachate is transferred to an equalization tank for storage and pH control process. After neutralization, leachate is introduced to an up flow and down flow anaerobic reactor. The effluent of anaerobic reactor is conducted to a sequencing batch reactor. Sequence batch reactor (SBR) effluent was pumped in to sand and activated carbon filters, after chemical coagulation and clarification. Results showed that anaerobic reactor with detention time of 3 days had a 35% COD removal and increasing the detention time to 4.5 days would improve the COD removal to 45%. Nutrient adjustment with phosphorus and nitrogen increased the initial 23% efficiency of sequence batch reactor to 44%. The effluent COD of SBR reactor was 21,309 mg/l. Recycling of aerobic reactor effluent with incoming feed to anaerobic reactor reduced the anaerobic reactor influent COD to 20,000 mg/l and this caused 53% and 57% COD removal in the anaerobic and aerobic effluent, respectively. The total systems COD performance increased to 80% and SBR effluent COD eventually reduced to 4,000 mg/l. Coagulation, flocculation and sedimentation processes were practiced to make the 4,000 mg/l effluent COD comply with environmental standards of Iran. The optimum coagulant found to be ferric chloride with the dosage of 50 mg/l at pH of 12, which reduced 10% of COD to an amount of 3,676 mg/l. The effluent was stored in a tank and then pumped in to pressure sand filter and afterwards to activated carbon filter. The COD removal was three and 90% for sand and activated carbon filters, respectively. The total process reduced the remaining COD to 36 mg/l, which is in compliance with environmental standards of Iran. 相似文献
16.
文章以金川和红原两组泥炭纤维素Δδ13C时间序列值的反向变化来指示西太平洋副热带高压活动变化.结果表明,在过去5000年中,西太平洋副热带高压的活动可分为4个阶段,即西太平洋副热带高压位置在2800～2200B.C.期间持续偏北,2200～600B.C.期间持续偏南,600B.C.～1200A.D.期间在北进与南移之间频繁波动,以及1200～1900A.D.期间再次持续偏北,它们导致降雨量在中国大陆上不同的分布.从约1900A.D.起西太平洋副热带高压的活动似乎又开始一个新的偏南阶段,值得进一步加强研究. 相似文献
17.
Mangrove forest stores large organic carbon stocks in a setting that is highly vulnerable to climate change and direct anthropogenic influences. As such there is a need to elucidate the causes and consequences of land use change on these ecosystems that have high value in terms of ecosystem services. We examine the areal pattern of land types in a coastal region located in southern Iran over a period of 14 years to predict future loss and gain in land types to the year 2025. We applied a CA–Markov model to simulate and predict mangrove forest change. Landsat satellite images from 2000 to 2014 were used to analyze the land cover changes between soil, open water and mangroves. Major changes during this period were observed in soil and water which could be attributed to rising sea level. Furthermore, the mangrove area in the more seaward position was converted to open water due to sea-level rise. A cellular automata model was then used to predict the land cover changes that would occur by the year 2025. Results demonstrated that approximately 21 ha of mangrove area will be converted to open water, while mangroves are projected to expand by approximately 28 ha in landward direction. These changes need to be delineated to better inform precise mitigation and adaptation measures. 相似文献
18.
Haydn H. Murray 《International Journal of Mineral Processing》1980,7(3):263-274
The kaolin industry has shown a phenomenal growth record from 1930 to the present and there is no indication that this growth will not continue. Innovative and efficient process developments enabled the kaolin industry to wet process over 5,000,000 tons in 1978 in Georgia and over 3,000,000 tons in the Cornwall district of southwestern England. These two regions supply the major tonnage of paper coating clays for the world's paper industry. The more important process developments are listed as follows: (1) development of chemicals for dispersion and flocculation; (2) continuous blungers to slurry the kaolin at the mine; (3) (continuous degritting by rake classifiers and hydrocyclones; (4) transport of kaolin slurry through pipelines from mine to plant; (5) continuous centrifuges for particle separation into coarse, medium, and fine sizes (6) chemical leaching of iron to improve brightness and color, (7) dewatering to high solids by: (a) continuous rotary vacuum filters; (b) automated plate and frame filter presses; (c) tube presses; (d) high speed contrifuges; (8) spray drying to low moisture and spherical shape to permit bulk hopper car shipments; (9) flotation to remove iron and titanium impurities to improve brightness and whiteness; (10) slurry clay shipments at 70 percent solids in tank cars; (11) high gradient magnetic separation to improve brightness and whiteness and to utilize marginal deposits; (12) delamination to utilize course kaolin stacks to make an improved product; (13) pugging and working the kaolin to improve viscosity; (14) a new development — dewatering to 80 to 85 percent solids using electrophoresis.Each of these developments is described and the future need to develop an efficient process to significantly lower the viscosity of high viscosity kaolins is discussed. 相似文献
19.
This paper focuses on what observers have perceived to be a failure of development leading to a ‘crisis of youth’ as increasing numbers of young people find it more difficult to gain education, access to health, a job and meet standard of living aspirations. For some, a possible escape is offered by migration to Europe, the United States or Australia, often illegally. For those remaining behind, however, international development agencies offer a ‘globalisation of solutions’ to employment, gender inequality and poverty through the millennium development goals and the programmes to attain them. In this paper we do not take the failures of development at face value but look at local contexts to present a more complex picture of the relation between education, work and social life. Based on fieldwork conducted in urban areas of The Gambia and Ghana, we argue that rather than education as a catch-all solution we need to give more attention to the costs incurred by and for young people in pursuing education and training, to the operation of and actual opportunities in labour markets, and to patterns of gender socialisation which give women limited scope to exercise agency. This paper explores key gender dimensions of work and education among low-income urban youth noting that despite on-going efforts to increase young women’s enrolment in schools and access to employment, gender inequalities have been far from eradicated. Our field interviews reveal how social expectations that women should perform the bulk of reproductive labour in their youth as well as in adulthood and constraints placed on young women’s personal freedom in respect of their social relationships reduce time dedicated to education and establish fewer contacts relevant to securing paid employment. The result is for men to end up with more educational qualifications, more skills, and higher-paying jobs, even if unemployment among young people in general remains a major problem. 相似文献
20.
矿业城市矿产资源可持续力比较评价 总被引：3，自引：0，他引：3
从发展和循环经济的观点看, 由于科技进步的贡献, 矿产资源不仅取决于现今已发现的矿产资源, 还依赖于未来新的和潜在的矿产资源以及替代资源.基于此, 提出“矿产资源可持续力”新概念, 以表征其对人类社会发展的贡献能力.以系统论与可持续发展理论为基石, 建立了“矿产资源可持续力”概念模型及其指标体系, 以及区际间矿产资源可持续力的六因子评价模型, 对中国50座典型矿业城市进行了比较评价, 指出其可持续力演变规律为: 从矿业类型来看, 可持续力沿着石油、综合、冶金、煤炭类逐渐劣化; 从城市发展阶段来看, 沿着中、幼、老年顺序依次下降; 从城市地理分布来看, 沿着东、西、中部逐渐下降; 从城市规模来看, 按照小型、大型及以上、中型城市顺序依次下降.为国家开发矿业城市和矿业城市可持续发展提供了科学的决策依据. 相似文献