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101.
海岸带临港工业、海运物流与全球化大生产的探讨   总被引:5,自引:0,他引:5  
海岸带是世界人口密集、经济发达的地带,在全球经济一体化和全球化大生产中具有重要的地位。近半个世纪以来,海岸带临港工业迅速崛起并持续高速发展,依托海港建设、大型船舶运输发展起来的临港工业和海运物流,在跨国公司的运作下形成了现代意义上的全球化大生产。这种生产方式使资源贫乏的日本快速发展成发达国家;深圳赤湾临港工业区成为中国高效益工业的典范。本文着重讨论了海岸带经济建设中大力发展临港工业对地区、国家和全球经济的影响,指出中国21世纪应大力开发利用海岸带港湾资源、重点建设全球化大生产的大进大出的基地,建立若干个具有国际竞争力的海岸带产业中心,推动国民经济持续、快速发展。  相似文献   
102.
Global dust trajectories indicate that signi?cant quantities of aeolian‐transported iron oxides originate in contemporary dryland areas. One potential source is the iron‐rich clay coatings that characterize many sand‐sized particles in desert dune?elds. This paper uses laboratory experiments to determine the rate at which these coatings can be removed from dune sands by aeolian abrasion. The coatings impart a red colour to the grains to which previous researchers have assigned variable geomorphological signi?cance. The quantities of iron removed during a 120 hour abrasion experiment are small (99 mg kg?1) and dif?cult to detect by eye; however, high resolution spectroscopy clearly indicates that ferric oxides are released during abrasion and the re?ectance of the particles alters. One of the products of aeolian abrasion is ?ne particles (<10 µm diameter) with the potential for long distance transport. Copyright © 2004 John Wiley & Sons, Ltd.  相似文献   
103.
M W Pasquini  F Harris 《Area》2005,37(1):17-29
Waste disposal constitutes an acute problem in numerous African cities. One solution could lie in the recycling of the nutrient-rich waste into agriculture taking place in and around cities. Farmers involved in vegetable production around Jos, Nigeria, have developed a sophisticated soil fertility management strategy combining inorganic fertilizers, manure and urban waste ash. This paper: (1) investigates the socio-economic constraints linked to obtaining scarce organic inputs, particularly urban waste ash and the health hazards (particularly heavy metal contamination of soil and crops) caused by using this ash and (2) suggests ways to improve use of this important resource.  相似文献   
104.
In this paper, the results of a survey conducted in the Cukurova region of Turkey are presented. The aim of this research is to identify groups of farmers who differ in their risk sources and risk management strategies. The respondents to the survey were divided into three risk attitude groups, risk averse, risk seeking and risk neutral. Factor analysis has been conducted on information obtained from 112 farmers in 2000. From the findings of the research, risk sources were labelled as environmental, price, catastrophe, input costs, production and technological, political, finance, personal, marketing, health and social security. The dimensions of risk strategies were named as diversification, off-farm income, marketing, planning, financing and security.  相似文献   
105.
通过核实从数据采集到标准时点阶段发生变化的内容,补充新增内容,消除普查前阶段由于资料时效性和外业局限性等导致的现势性不统一现象,对变化的地理国情信息进行核准,使地理国情普查数据成果在时间上达到统一,是开展地理国情监测的基础。  相似文献   
106.
城市测量的种类多且内业成果复杂,天津对各项内业成果都有特定的要求,急需一个统一的生产平台。通过对勘测定界、地籍等9类项目进行分析,规范了生产制作流程,制定了描述多种数据格式的标准,设计了系统结构,在AutoCAD基础上开发实现了天津测绘生产自动化系统。系统以项目工程为单元对成果数据进行管理,实现了标准化生产。  相似文献   
107.
张菡  刘晓璐  房鹏 《气象科技》2016,44(3):468-473
以四川烤烟主产区冰雹灾害为研究对象,将烤烟气候适应性特征和自然灾害系统论相结合,利用冰雹频率、DEM高程数据、下垫面类型以及农业经济数据等资料,构建冰雹灾害风险评估指标体系,从致灾因子危险性、孕灾环境敏感性、承灾体易损性和抗灾能力4个方面进行分析,最终建立四川烤烟主产区冰雹灾害精细化风险评估模型并计算风险分布指数,借此将攀西烟区划分为由高至低的5个风险区域和1个不适宜种植区。结果表明,安宁河源头河谷地区、雅砻江下游流域以及攀西地区南部的河谷低山区和丘陵区冰雹灾害风险处于较高水平。评估结果为区域烤烟种植结构调整及冰雹灾害防御工作提供了科学指导。  相似文献   
108.
Bulk mineral resources of iron ores, copper ores, bauxite, lead ores, zinc ores and potassium salt play a pivotal role on the world’s and China’s economic development. This study analyzed and predicted their resources base and potential, development and utilization and their world’s and China’s supply and demand situation in the future 20 years. The supply and demand of these six bulk mineral products are generally balanced, with a slight surplus, which will guarantee the stability of the international mineral commodity market supply. The six mineral resources(especially iron ores and copper ores) are abundant and have a great potential, and their development and utilization scale will gradually increase. Till the end of 2014, the reserveproduction ratio of iron, copper, bauxite, lead, zinc ores and potassium salt was 95 years, 42 years, 100 years, 17 years, 37 years and 170 years, respectively. Except lead ores, the other five types all have reserve-production ratio exceeding 20 years, indicative of a high resources guarantee degree. If the utilization of recycled metals is counted in, the supply of the world’s six mineral products will exceed the demand in the future twenty years. In 2015–2035, the supply of iron ores, refined copper, primary aluminum, refined lead, zinc and potassium salt will exceed their demand by 0.4–0.7 billion tons(Gt), 5.0–6.0 million tons(Mt), 1.1–8.9 Mt, 1.0–2.0 Mt, 1.2–2.0 Mt and 4.8–5.6 Mt, respectively. It is predicted that there is no problem with the supply side of bulk mineral products such as iron ores, but local or structural shortage may occur because of geopolitics, monopoly control, resources nationalism and trade friction. Affected by China’s compressed industrialized development model, the demand of iron ores(crude steel), potassium salt, refined lead, refined copper, bauxite(primary aluminum) and zinc will gradually reach their peak in advance. The demand peak of iron ores(crude steel) will reach around 2015, 2016 for potassium salt, 2020 for refined lead, 2021 for bauxite(primary aluminum), 2022 for refined copper and 2023 for zinc. China’s demand for iron ores(crude steel), bauxite(primary aluminum) and zinc in the future 20 years will decline among the world’s demand, while that for refined copper, refined lead and potassium salt will slightly increase. The demand for bulk mineral products still remains high. In 2015–2035, China’s accumulative demand for iron ores(crude steel) will be 20.313 Gt(13.429 Gt), 0.304 Gt for refined copper, 2.466 Gt(0.616 Gt) of bauxite(primary aluminum), 0.102 Gt of refined lead, 0.138 Gt of zinc and 0.157 Gt of potassium salt, and they account for the world’s YOY(YOY) accumulative demand of 35.17%, 51.09%, 48.47%, 46.62%, 43.95% and 21.84%, respectively. This proportion is 49.40%, 102.52%, 87.44%, 105.65%, 93.62% and 106.49% of that in 2014, respectively. From the supply side of China’s bulk mineral resources, it is forecasted that the accumulative supply of primary(mine) mineral products in 2015–2035 is 4.046 Gt of iron ores, 0.591 Gt of copper,1.129 Gt of bauxite, 63.661 Mt of(mine) lead, 0.109 Gt of(mine) zinc and 0.128 Gt of potassium salt, which accounts for 8.82%, 13.92%, 26.67%, 47.09%, 33.04% and 15.56% of the world’s predicted YOY production, respectively. With the rapid increase in the smelting capacity of iron and steel and alumina, the rate of capacity utilization for crude steel, refined copper, alumina, primary aluminum and refined lead in 2014 was 72.13%, 83.63%, 74.45%, 70.76% and 72.22%, respectively. During 2000–2014, the rate of capacity utilization for China’s crude steel and refined copper showed a generally fluctuating decrease, which leads to an insufficient supply of primary mineral products. It is forecasted that the supply insufficiency of iron ores in 2015–2035 is 17.44 Gt, 0.245 Gt of copper in copper concentrates, 1.337 Gt of bauxite, 38.44 Mt of lead in lead concentrates and 29.19 Mt of zinc in zinc concentrates. China has gradually raised the utilization of recycled metals, which has mitigated the insufficient supply of primary metal products to some extent. It is forecasted that in 2015–2035 the accumulative utilization amount of steel scrap(iron ores) is 3.27 Gt(5.08 Gt), 70.312 Mt of recycled copper, 0.2 Gt of recycled aluminum, 48 Mt of recycled lead and 7.7 Mt of recycled zinc. The analysis on the supply and demand situation of China’s bulk mineral resources in 2015–2035 suggests that the supply-demand contradiction for these six types of mineral products will decrease, indicative of a generally declining external dependency. If the use of recycled metal amount is counted in, the external dependency of China’s iron, copper, bauxite, lead, zinc and potassium salt will be 79%, 65%, 26%, 8%, 16% and 18% in 2014, respectively. It is predicted that this external dependency will decrease to 62%, 64%, 20%,-0.93%, 16% and 14% in 2020, respectively, showing an overall decreasing trend. We propose the following suggestions correspondingly.(1) The demand peak of China’s crude steel and potassium salt will reach during 2015–2023 in succession. Mining transformation should be planned and deployed in advance to deal with the arrival of this demand peak.(2) The supply-demand contradiction of China’s bulk mineral resources will mitigate in the future 20 years, and the external dependency will decrease accordingly. It is suggested to adjust the mineral resources management policies according to different minerals and regions, and regulate the exploration and development activities.(3) China should further establish and improve the forced mechanism of resolving the smelting overcapacity of steel, refined copper, primary aluminum, lead and zinc to really achieve the goal of "reducing excess production capacity".(4) In accordance with the national strategic deployment of "One Belt One Road", China should encourage the excess capacity of steel, copper, alumina and primary aluminum enterprises to transfer to those countries or areas with abundant resources, high energy matching degree and relatively excellent infrastructure. Based on the national conditions, mining condition and geopolitics of the resources countries, we will gradually build steel, copper, aluminum and lead-zinc smelting bases, and potash processing and production bases, which will promote the excess capacity to transfer to the overseas orderly.(5) It is proposed to strengthen the planning and management of renewable resources recycling and to construct industrial base of renewable metal recycling.(6) China should promote the comprehensive development and utilization of paragenetic and associated mineral species to further improve the comprehensive utilization of bulk mineral resources.  相似文献   
109.
吕士东  孙友宏  李强  郭威  周科  王思远 《世界地质》2016,35(4):1185-1194
为有效地扩大油页岩原位开采区域和节约油页岩原位开采的成本,需将废置的降水井改造成为原位生产井。根据降水井与原位生产井井身结构的相似性,对农安油页岩原位开采先导试验工程基地的降水井改造工艺进行了设计和优化。同时研发了偏心轮式套管割管装置及三爪式套管打捞装置用于拔管施工。工程实践证明,该工艺具有步骤简单、合理、高效以及价格低廉等特点。偏心轮式套管割管装置及三爪式套管打捞装置应用在降水井改造中,均取得理想的效果。  相似文献   
110.
"罗布泊超大型卤水鉀矿"的发现,是中国众多地学科学家40年探寻预测的。王弭力研究员及其团队,于1995年秋首次踏进罗布泊"罗北凹地",当年找到4356万t优质卤水鉀矿;经五年科研和勘探,查明儲量达2.5亿t、为超大型卤水鉀矿。理论创新,成为完成科硏和勘探的关键,加速了百万吨级"罗钾公司"硫酸钾肥生产成功投产。古丝绸之路上生命回归、一颗新星"罗布泊"镇诞生,"百年罗钾"资源保障科研探钾即将启动,中国几代"钾盐人"的梦想成真。  相似文献   
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