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91.
The quality of effluent from an on-site sewage treatment system is a critical factor in designing the disposal area and, hence, ensuring the sustained performance of the system. Contaminant concentrations in effluent are typically specified in regulatory guidelines or standards; however, the accuracy of these guideline values are brought into question due to the poor performance of septic tanks and the high failure rates of disposal systems reported here and elsewhere. Results from studies of septic tank effluent quality indicated that the effluent is of poorer quality than currently suggested by guidelines. Aerated wastewater treatment systems were found to perform to accreditation guidelines; however, insufficient nutrient data is presently available to assess nutrient loads. It is proposed that the 80th percentile of system performance be adopted as the design value for sizing effluent disposal areas to minimise failure associated with overloading. For septic tanks this equates to 660 mg L(-1) SS, 330 mg L(-1) BOD, 250 mg L(-1) TN and 36 mg L(-1) TP.  相似文献   
92.
This paper studies the influence of ripening stage and maceration time (1–23 days) on the contribution of each cluster grape components to phenolic composition and astringency in wine-simulated macerations. In general terms, proanthocyanidin extraction from skins, stems and especially from seeds increased with maceration time. The ripening stage also had a major influence on tannin extraction and astringency. The tannin contribution from skins and stems increased with ripening but the contribution from the seeds decreased. The contribution to astringency from all cluster components was clearly higher when the grapes were unripened. The mean degree of polymerization of the tannins from skin and seed components was unaffected by ripening and maceration length.  相似文献   
93.
Contemporary science and environmental news coverage of global warming increasingly portrays scientific consensus. Political news coverage of global warming, however, typically portrays controversy. We hypothesize that attention to science and environmental news is associated with beliefs more consistent with the global warming science and higher risk perceptions, and that the opposite is true of attention to political news. Furthermore, we hypothesize that science‐based beliefs and risk perceptions are positively associated with support for policies aiming at reducing global warming. These hypotheses were confirmed by survey data from a nationally representative sample of adults (N = 2,164). These findings support and extend the cognitive mediation model of news learning and have important practical ramifications.  相似文献   
94.
The synthesis of a monosilylated Hoveyda‐type monomer is described as well as the preparation of several organic‐inorganic hybrid materials derived from it by sol‐gel processes and by anchoring to commercial silica gel and MCM‐41. The resulting materials were treated with first and/or second generation Grubbs’ catalyst to generate Hoveyda–Grubbs’ type alkylidene ruthenium complexes covalently bonded to the silica matrix. These materials are efficient recyclable catalysts for the ring‐closing metathesis reaction of dienes and enynes, even for the formation of tri‐ and tetrasubstituted olefins.  相似文献   
95.
The focused ion microprobe of the Laboratori Nazionali di Legnaro has been recently employed in experiments requiring very low beam current. This article will discuss the performance of our apparatus in this application, the drawbacks which showed up and the appropriate solutions. We present IBIC observations of grain boundaries in polycrystalline silicon solar cells and IBIC and IBIL measurements on CVD diamond samples. The modifications introduced in the experimental setup are outlined. We emphasise the problems typical of these measurements and propose the interposition of thin gold foils in the beam line, as a way to handle very different current intensities. We study the effects of these foils on beam quality and their effectiveness in reducing the current. A new designed system for easy interchange of foils and related collimators is described, which will be inserted upstream in the beam line.  相似文献   
96.
BACKGROUND: The cut-off point of serum C-reactive protein to differentiate the mild from the severe form of acute pancreatitis is still debated; data concerning the C-reactive protein pattern in assessing the severity of acute biliary pancreatitis are lacking. AIM: To define the best cut-off point in differentiating the severe from the mild form of acute biliary pancreatitis. PATIENTS: Fifty patients with acute biliary pancreatitis: 34 patients with mild pancreatitis and 16 with the severe form of the disease were studied. METHODS: Serum C-reactive protein concentrations were assessed in all patients upon admission and for the following 5 days. RESULTS: No significant difference in serum C-reactive protein levels was found in the first 2 days in patients with mild pancreatitis compared to those with the severe form of the disease. Using a cut-off point of 11 mg/dl, the sensitivity of serum C-reactive protein in assessing the severity of acute pancreatitis during the first two days of the study was 9% and 57%, the specificity, 93% and 81%, and the accuracy 71% and 74%, respectively. CONCLUSIONS: Serum determination of C-reactive protein in the first 48 hours of the disease is not a reliable marker of the severity of acute biliary pancreatitis.  相似文献   
97.
98.
This paper provides data on the changing character of river restoration within one country within a single policy and legislative framework. The information gathered was based on web searches, meetings and questionnaire responses with organizations and individuals working as environmental policy developers, stakeholders and practitioners of catchment management and river restoration. The paper utilizes this information to explore generic issues promoting and constraining a move to integrated catchment scale river restoration. Catchment scale river restoration was defined as ‘any river restoration activity that singly, or in combination, restores natural catchment processes and a naturally functioning ecosystem and brings benefit or environmental services to the whole catchment and not just to the site of restoration’. The river restoration project data compiled showed that the number of projects in Scotland is on a strong upward trajectory, but the number of catchment scale projects is still limited. The data also showed a trend towards a range of underpinning reasons for river restoration. Traditionally the reasons for river restoration in Scotland have been strongly fisheries focussed, with another key driver being biodiversity conservation. Sustainable flood management and climate change adaptation are seen as emerging drivers of river restoration. In terms of the individuals interviewed, most appreciated that river restoration can bring about multiple benefits and should be underpinned by a good understanding of catchment processes. Our overall assertion based on our study is that unless there is a fundamental paradigm shift, a change in the nature and level of funding for river restoration and a single organization is given overall authority to direct river restoration. ‘business as usual’ will continue and the benefits of catchment scale river restoration will be limited. Copyright © 2010 John Wiley & Sons, Ltd.  相似文献   
99.
Mixtures of diglycidylether of bisphenol A (DGEBA) with 1,3‐benzodioxolane‐2‐one (CC) or 4‐phenoxymethyl‐1,3‐dioxolane‐2‐one (PGEC) were cured in the presence of lanthanum triflate. FTIR/ATR was used to study the evolution of carbonate and epoxide groups to follow the reactive processes that take place during curing. DSC was applied to study the thermal characteristics of the curing process and to determine the glass‐transition temperatures of the cured materials. The kinetics of the curing was studied isothermally by means of FTIR and the kinetic model was selected through the isokinetic relationships. DSC experiments were used to study the kinetics in nonisothermal conditions by means of isoconversional procedures and the Coats–Redfern and Criado methodologies. By TMA we could monitor the evolution of the shrinkage during isothermal curing. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 103: 2875–2884, 2007  相似文献   
100.
This paper studies how the use of bentonite to facilitate the riddling process affects the foam properties and the protein fraction of sparkling wines (Cava). In all monovarietal sparkling wines (Macabeu, Xarel.lo, Parellada, Chardonnay and Pinot Noir), the addition of bentonite produced a statistically significant diminution of the Mosalux parameters (HM and HS). This depreciation of the foam quality may be attributed to the direct interaction of bentonite with wine proteins. Concretely the use of bentonite caused a diminution of more of 80% of total the soluble protein. Gel filtration by FPLC showed that bentonite particularly affected the 60 kDa and 20–30 kDa protein fraction. The high molecular fraction, on the other hand, was not affected.  相似文献   
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