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11.
This article examines the impact of decentralization reforms on improving access to domestic water supply in the rural districts of Kondoa and Kongwa, Tanzania, using a users' and a gender perspective. The article addresses the question whether and to what extent the delivery of gender-sensitive water services to rural households improved after the reforms. Household- and village-level data were obtained through a household survey and qualitative methods. The findings show an increase of the proportion of households using improved sources of domestic water between 2002 and 2011. However, more than half of users still travel over a kilometre and use more than an hour to collect water in the dry season. Despite the increased proportion of women in water management committees, the outcomes of these decentralized arrangements differ for men and women. Overall, the reforms have produced contradictory effects by improving access to water supply for some users, and creating or reinforcing existing inter- and intra-village inequalities.  相似文献   
12.
I. Stober  K. Bucher 《Geofluids》2015,15(3):464-482
Hydraulic and hydrochemical data from several hundred wells mostly drilled by the oil and gas industry within the four deep carbonate and siliciclastic reservoirs of the Upper Rhine Graben area in France and Germany have been compiled, examined, validated and analysed with the aim to characterize fluids and reservoir properties. Due to enhanced temperatures in the subsurface of the Upper Rhine Graben, this study on hydraulic and hydrochemical properties has been motivated by an increasing interest in deep hydrogeothermal energy projects in the Rhine rift valley. The four examined geothermal reservoir formations are characterized by high hydraulic conductivity reflecting the active tectonic setting of the rift valley and its fractured and karstified reservoirs. The hydraulic conductivity decreases only marginally with depth in each of the reservoirs, because the Upper Rhine Graben is a young tectonically active structure. The generally high hydraulic conductivity of the reservoir rocks permits cross‐formation advective flow of thermal water. Water composition data reflect the origin and hydrochemical evolution of deep water. Shallow water to 500 m depth is, in general, weakly mineralized. The chemical signature of the water is controlled by fluid–rock geochemical interactions. With increasing depth, the total of dissolved solids (TDS) increases. In all reservoirs, the fluids evolve to a NaCl‐dominated brine. The high salinity of the reservoirs is partly derived from dissolution of halite in evaporitic Triassic and Cenozoic formations, and partly from the fluids residing in the crystalline basement. Water of all four reservoirs is saturated with respect to calcite and other minerals including quartz and barite.  相似文献   
13.
L. Jiang  W. Pan  C. Cai  L. Jia  L. Pan  T. Wang  H. Li  S. Chen  Y. Chen 《Geofluids》2015,15(3):483-498
Permian hydrothermal activity in the Tarim Basin may have been responsible for the invasion of hot brines into Ordovician carbonate reservoirs. Studies have been undertaken to explain the origin and geochemical characteristics of the diagenetic fluid present during this hydrothermal event although there is no consensus on it. We present a genetic model resulting from the study of δ13C, δ18O, δ34S, and 87Sr/86Sr isotope values and fluid inclusions (FIs) from fracture‐ and vug‐filling calcite, saddle dolomite, fluorite, barite, quartz, and anhydrite from Ordovician outcrops in northwest (NW) Tarim Basin and subsurface cores in Central Tarim Basin. The presence of hydrothermal fluid was confirmed by minerals with fluid inclusion homogenization temperatures being >10°C higher than the paleo‐formation burial temperatures both in the NW Tarim and in the Central Tarim areas. The mixing of hot (>200°C), high‐salinity (>24 wt% NaCl), 87Sr‐rich (up to 0.7104) hydrothermal fluid with cool (60–100°C), low‐salinity (0 to 3.5 wt% NaCl), also 87Sr‐rich (up to 0.7010) meteoric water in the Ordovician unit was supported by the salinity of fluid inclusions, and δ13C, δ18O, and 87Sr/86Sr isotopic values of the diagenetic minerals. Up‐migrated hydrothermal fluids from the deeper Cambrian strata may have contributed to the hot brine with high sulfate concentrations which promoted thermochemical sulfate reduction (TSR) in the Ordovician, resulting in the formation of 12C‐rich (δ13C as low as ?13.8‰) calcite and 34S‐rich (δ34S values from 21.4‰ to 29.7‰) H2S, pyrite, and elemental sulfur. Hydrothermal fluid mixing with fresh water in Ordovician strata in Tarim Basin was facilitated by deep‐seated faults and up‐reaching faults due to the pervasive Permian magmatic activity. Collectively, fluid mixing, hydrothermal dolomitization, TSR, and faulting may have locally dissolved the host carbonates and increased the reservoir porosity and permeability, which has significant implications for hydrocarbon exploration.  相似文献   
14.
明朝初年,国脉皆仰东南,为解决南方粮财物的北运问题,宋礼和白英受命组织修建了大运河山东段南旺分水枢纽。该枢纽主要包括引汶济运、导泉补源、设立水柜和置闸节流四个组成部分。其中,引汶济运是工程之重点,包括戴村坝、小汶河、南旺分水以及配套工程等四个子系统。这些水利设施组成一个和谐的系统工程,保证了该段运河的水量稳定充足,从而实现了大运河500余年的正常通行。南旺分水枢纽代表了我国古代运河水工的最高科学技术成就,堪称世界水利史上的一大经典范例。  相似文献   
15.
Climate-driven water variability is a natural phenomenon that is observed across river basins, but one that is predicted to increase due to climate change. Environmental change of this kind may aggravate political tensions, especially in regions which are not equipped with an appropriate institutional apparatus. Increased variability is also likely to challenge regions with existing institutional capacity. We argue that our best attempts to assess the ability of states to deal with variability in the future rest with considering how agreements have fared in the past. In this paper, we explore treaty effectiveness, or treaty resilience, by investigating whether particular water allocation and institutional mechanisms help mitigate inter-country tensions over shared water. We use water-related events from the Basins at Risk events database as a dependent variable to test particular hypotheses regarding the impact of treaty design on conflict and cooperation over time. A broad set of climatic, geographic, political, and economic variables are used as controls. The analysis is conducted for the years 1948–2001 using the country dyad as the level of observation. Findings pertaining to our primary explanatory variables suggest that country dyads governed by treaties with water allocation mechanisms exhibiting both flexibility and specificity evince more cooperative behavior. Country dyads governed by treaties with a larger sum of institutional mechanisms likewise evince a higher level of cooperation, although certain institutional mechanisms appear to be more important than others.  相似文献   
16.
This paper discusses three normative standpoints on conflict in strategic spatial planning: no conflict, conflict for consensus and conflict for meta-consensus on the validity of dispute. These views apply to the questions of whether and why projects, as a major source of conflict, should be identified in the process of strategic planning. In their approaches to these questions, the performance school advocates the production of general guidelines to avoid conflict, the collaborative perspective supports the identification of projects in strategic planning in order to utilize their potential in a conflict-to-consensus journey and the conflict-oriented perspective favours the identification of projects in strategic planning in order to arrive at meta-consensus on the immediate disputability of robust agreements. Reflecting on the collaborative perspective, this paper tests a hypothetical model of how conflicts created in the face of project identification can feed in making consensual strategies. Findings in the North West region of England support the model and suggest some difficulties with reviewing such consensus around which a resistance network forms. The paper puts forward some recommendations for overcoming the review challenge.  相似文献   
17.
Gender differences in mobility patterns between women and men have long been acknowledged. This study analyses how these differences are reproduced in different urban and rural contexts. Using mobility data from a large travel survey taken in 2006 in Spain, we examine the differences between gender mobility through age, modal split and trip purposes. Special attention is paid to how territory shapes mobility and how these territorial settings differently affect gendered mobilities. The use of this data source allows the comparison of all trips made by the total population, including all means of transport. By taking a global view on mobility, the uneven relationships that men and women have with different means of transport become more visible. After disaggregating data by age and territorial settings, results show that women are using sustainable transport modes more often than men, and travelling for more diverse reasons. Gender is thus a fundamental variable in understanding modal split and, by extension, transport sustainability, in terms of energy consumption and the emission of greenhouse gases. From this point of view, we consider women's mobility knowledge and practices – typically related to the most sustainable means of transport – as factors with rising value that could effectively guide public policy in its way to promote more sustainable mobility patterns.  相似文献   
18.
In more than 75% of households around the world in which water needs are fulfilled by retrieving water, women are typically tasked with this critical responsibility. This is true in Kenya, and the challenges women in rural areas of the country face are compounded by a lack of reasonable access to safe water by 56.5% of rural households. More than 25% of the population must travel at least 30?minutes to collect water, and 70% of all diseases in the country are water-borne (Kameri-Mbote and Kariuki 2015). Given their role as the primary household decision-maker about water, women have an astute understanding of water availability, access, quality and household use, and women’s perspectives would enhance decision-making in groups that address water resource management. However, women have historically been marginalized from participation in such processes for numerous reasons related to lack of empowerment, leadership, and voice, and the practicalities of the demands on her time that prevent her from having discretionary time to devote to civic processes. In this study, we interviewed 153 women living in three different watersheds in the Laikipia region of central Kenya about their views on water resource management, and interest in participation in water resource user associations (WRUAs) as members and leaders. Our results are consistent with prior research in that marginalization of women from WRUA participation is steeped in entrenched normative beliefs and behaviors about women’s roles and her domestic responsibilities, a lack of money to participate, and a lack of time given her other responsibilities.  相似文献   
19.
Abstract

This article discusses the issue of the Ming army's maritime shipping of supplies during the second stage of the East Asian War of 1597–8. Despite the lack of historical sources and difficulty in finding accurate numbers, Zhang Yangmeng's 張養蒙 memorials include records of maritime transport decisions, implementation, effectiveness, and limitations and are of great help to filling in the blank areas of research in Ming army logistics.  相似文献   
20.
水东宋氏从唐初至明末统治贵州水东地区,唐宋元明四朝先后封赐诸多官衔。通过对水宋氏所任职衔的研究,可充分认识其兴起、发展、兴盛和衰亡过程,也可窥见中央王朝的治黔方略及贵阳政区的形成过程。  相似文献   
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