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21.
This paper highlights the key issues which affected the design and implementation of water policy within the first phase of the Environmental Programme for the Danube River Basin. The programme represents one of several regional environmental initiatives in Eastern Europe which were designed to control pollution through the coordinated actions of national governments, international organizations, international financial institutions and non-governmental organizations.
The paper identifies three key controversial findings. Firstly, although the programme has been a valuable tool for the skills and technology transfer which are necessary to enable the Danube states to control water pollution, it has failed to generate the anticipated levels of capital investment or establish itself as a cornerstone of Danube basin management. Secondly, the policy process has been beset by political, economic, social and historical conflicts and power struggles between the participating parties. Thirdly, valuable lessons for the strategic and sustainable management of international river basins can be learned from the operational experiences of the Danube programme. 相似文献
The paper identifies three key controversial findings. Firstly, although the programme has been a valuable tool for the skills and technology transfer which are necessary to enable the Danube states to control water pollution, it has failed to generate the anticipated levels of capital investment or establish itself as a cornerstone of Danube basin management. Secondly, the policy process has been beset by political, economic, social and historical conflicts and power struggles between the participating parties. Thirdly, valuable lessons for the strategic and sustainable management of international river basins can be learned from the operational experiences of the Danube programme. 相似文献
22.
A. KENT BSc DMS CEng MICE MBIM D. WILSON BSc DIS D. M. PICKLES CEI 《Water and Environment Journal》1987,1(3):349-358
T he A lbert R eservoir of the Yorkshire Water Authority was built in the 1850s as the final raw water storage in the chain of impounding and storage reservoirs which feed Halifax, Brighouse, and Elland in West Yorkshire (Fig. 1).
This paper describes the problems encountered with increasing raw water colour since the mid1970s, the action taken to pretreat the water at the Albert reservoir prior to pressure filtration at the Thrum Hall Water Treatment Works (WTW), and the resulting problems with the deposited alum sludge in Albert reservoir. 相似文献
This paper describes the problems encountered with increasing raw water colour since the mid1970s, the action taken to pretreat the water at the Albert reservoir prior to pressure filtration at the Thrum Hall Water Treatment Works (WTW), and the resulting problems with the deposited alum sludge in Albert reservoir. 相似文献
23.
The availability of thermoplastic resins as matrix materials for short and continuous fibre reinforced composites offers the possibility of joining these materials by welding. A number of welding processes are available to suit different industrial needs, and their use increases the scope for designing and manufacturing new types of industrial product. This paper introduces the principle welding methods available for joining thermoplastic composites, and gives initial results of their use for the joining of an advanced continuous fibre thermoplastics. 相似文献
24.
A. D. Wheatley BSc PhD M. B. Fisher MRSC CChem A. M. W. Grobicki BSc PhD MIChemE CEng 《Water and Environment Journal》1997,11(1):39-46
For many decades, anaerobic digestion has been the most important technique of sewage sludge treatment at larger sewage-treatment works. Also, the low running costs of the process make it attractive for the treatment of strong industrial effluents. This paper reviews these advantages and discusses some disadvantages of the anaerobic treatment of industrial effluent. Operating and cost data are presented from Europe and from a detailed UK case study which supports the conclusion that anaerobic treatment will be the most cost-effective method of treatment of strong industrial effluents such as those from food and paper processing. 相似文献
25.
Optimum Design of Sewage Sludge Consolidation Tanks 总被引:1,自引:0,他引:1
Consolidation is potentially the most cost-effective of all sludge treatment processes. However, traditional design procedures have been oversimplified such that the process has not generally been fully exploited.
The objective of this report is to summarize the Water Research Centre (WRc) procedure for sizing sewage sludge consolidation tanks, and explain the major design aspects which control the effective operation of the plant. The procedure provides a means of sizing tanks to consolidate any particular sewage sludge to any solids concentrations up to the maximum, and is applicable to both the batch and continuous operational modes. To obtain the predicted performance, the essential equipment such as the picket fence and control system, comprising a consolidation plant, must be suitably designed. 相似文献
The objective of this report is to summarize the Water Research Centre (WRc) procedure for sizing sewage sludge consolidation tanks, and explain the major design aspects which control the effective operation of the plant. The procedure provides a means of sizing tanks to consolidate any particular sewage sludge to any solids concentrations up to the maximum, and is applicable to both the batch and continuous operational modes. To obtain the predicted performance, the essential equipment such as the picket fence and control system, comprising a consolidation plant, must be suitably designed. 相似文献
26.
J.F. Lyness BSc MSc PhD CEng MICE MIStructE W. R. C. Myers BA BSc PhD CEng MICE J. B. Wark BEng PhD 《Water and Environment Journal》1997,11(5):335-340
Flow measurements have been taken for steady and unsteady flows on a reach of a river having a compact compound channel. The 'single channel', 'divided channel' and 'lateral' distribution methods have been used to calculate conveyances for use in a one-dimensional unsteady flow model of the reach. Comparisons with measured flows show that the divided channel method and the lateral distribution method both underestimate floodplain flow depths. The lateral distribution method gives the closest accuracy in the relative depth range 0.15 ≤ Yr < 0.40. For large flow depths the single channel method becomes more accurate and slightly over-estimates flow depths.
The accuracy of unit width discharge distributions, calculated from the lateral distribution method are assessed by comparison with observed distributions for overbank flows. 相似文献
The accuracy of unit width discharge distributions, calculated from the lateral distribution method are assessed by comparison with observed distributions for overbank flows. 相似文献
27.
M. HUNTER BSc PhD MIBiol T. STEPHENSON BSc PhD MIBiol MRSC J. N. LESTER MSc PhD MIBiol 《Water and Environment Journal》1987,1(1):77-88
T he R emoval of heavy metals and aluminium residuals during upflow sludge-blanket clarification was investigated using a pilot-plant system. Pilot units treating predosed raw water on site were assessed for sludge-blanket formation and stabilization, and were found to produce clarified water of a comparable quality to the main works units after the start-up and stabilization periods were complete. The heavy metals Cr, Fe, Mn, and Ni were the only heavy metals detectable at the investigation site and these occurred at concentrations well below guidelines values for potable abstraction and supply.
Mean removals of Fe, Mn, Cr, and Ni were about 98, 89, 51, and 30 per cent respectively, during steady-state operation, and Fe, Mn, and Cr all displayed reduced removals during transient changes in surface load, whereas Ni removal appeared to be relatively independent. Aluminium residuals derived from the dosed alum coagulant also showed decreases in removal from about 83 per cent during steady-state operation to between 40 and 50 per cent during transient experiments. 相似文献
Mean removals of Fe, Mn, Cr, and Ni were about 98, 89, 51, and 30 per cent respectively, during steady-state operation, and Fe, Mn, and Cr all displayed reduced removals during transient changes in surface load, whereas Ni removal appeared to be relatively independent. Aluminium residuals derived from the dosed alum coagulant also showed decreases in removal from about 83 per cent during steady-state operation to between 40 and 50 per cent during transient experiments. 相似文献
28.
If a shoreline management plan is to lead to sustainable coastal defences, a long-term strategic view is necessary. This paper examines the issues which are involved in shoreline management planning and the role of the planning system in achieving sustainable coastal defence. Using case studies from the Holderness coastline, it (a) reviews the options with respect to erosion control on a rapidly eroding coast, and (b) acknowledges the need to introduce change gradually if it is to be accepted. Specifically, it assesses the potential to use planning permission controls to prevent new development in areas where maintaining a hard defence line will interrupt longshore transport, with potentially significant down-drift effects. 相似文献
29.
30.
J. H. COLLING BSc P. A. E. WHINCUP PhD C. R. HAYES BSc MSc MIBiol 《Water and Environment Journal》1987,1(3):263-269
A laboratory-scale lead-pipe rig has been developed into an accelerated test for 'plumbosolvency propensity'. High alkalinity water supplies from Anglian Water show either relatively high or low propensity characteristics which appear to be related to the form of the crystal deposit. These have been examined by scanning electron microscopy. The paper describes the uses of the test to (1) supplement random survey data, (2) investigate mixed waters, and (3) optimize orthophosphate dosing. 相似文献