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31.
The intent of this study is to contribute to the discussion of strategic environmental assessment (SEA) best practice based on experience gained in a recent SEA initiative: the central Namib (Namibia) uranium rush SEA. We evaluate this SEA process against internationally established characteristics of ‘best practice’ SEA to improve and strengthen future practice in Namibia. The study draws primarily on the final assessment report as well as inputs from six informants involved in the assessment. The results reveal some elements of good practice as well as areas for improvement, and in particular, the need for improved baseline data collection; adequate consideration of alternatives; committing to preferred scenario/options; enforceability; and a more robust institutional capacity. We offer insight into how consideration of these factors may help to strengthen SEA practice in Namibia. Overall, the SEA may not represent a ‘best practice’ example according to international standards, but it does suggest a potentially bright future for SEA practice in Namibia.  相似文献   
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Abstract

Regional environmental assessment (EA) requires the participation of policy- and plan-making institutions to formulate, implement and monitor regional environmental management strategies. However, there is little understanding of what effective integration is in the context of regional EA and from the perspectives of planners and policy-makers involved. This paper seeks to explore how institutional actors perceive cross-domain integration vis-à-vis their own involvement in regional EAs. Thirty-eight participants from four regional EA initiatives in Canada shared their perspectives in an online survey. Three types of silo effects are identified: (1) institutional – intricately linked to factors such as coordination, goals and expectations, leadership and capacity; (2) disciplinary – characterized by limited communication and scepticism around data sharing; and (3) transactional – tendency of actors to emphasize individual narrow perspective rather than collective social and environmental outcomes. Additional findings reveal the importance of learning and multiple domain expertise as opportunities for enhancing cross-domain integration in regional EA practice. Finally, the study concludes that proactive consideration of potential silo effects is necessary for improved regional EA outcomes, and to facilitate more effective regional resource governance.  相似文献   
33.
A simple, versatile method for non‐covalent functionalization of graphene based on solution‐phase assembly of alkane‐amine layers is presented. Second‐order Møller–Plesset (MP2) perturbation theory on a cluster model (methylamine on pyrene) yields a binding energy of ≈220 meV for the amine–graphene interaction, which is strong enough to enable formation of a stable aminodecane layer at room temperature. Atomistic molecular dynamics simulations on an assembly of 1‐aminodecane molecules indicate that a self‐assembled monolayer can form, with the alkane chains oriented perpendicular to the graphene basal plane. The calculated monolayer height (≈1.7 nm) is in good agreement with atomic force microscopy data acquired for graphene functionalized with 1‐aminodecane, which yield a continuous layer with mean thickness ≈1.7 nm, albeit with some island defects. Raman data also confirm that self‐assembly of alkane‐amines is a non‐covalent process, i.e., it does not perturb the sp2 hybridization of the graphene. Passivation and adsorbate n‐doping of graphene field‐effect devices using 1‐aminodecane, as well as high‐density binding of plasmonic metal nanoparticles and seeded atomic layer deposition of inorganic dielectrics using 1,10‐diaminodecane are also reported.  相似文献   
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The effects of raw material, processing conditions and packaging on the quality of plantain chips were investigated. Two cultivars of plantain Musa spp—Agbagba and Obino lewai—as well as cooking banana were used for the study. The fruits were at stages 1 to 4 of the banana ripening chart. The study started with a consumer survey aimed at product definition. This was followed by series of experiments to determine the effects of raw material, processing conditions and packaging on the quality of plantain chips. A correlation analysis was also carried out on the physical and chemical characteristics of raw plantain. The work revealed that the stage of ripeness of raw material had some effect on the quality of chips as there was gradual increase in pulp/peel ratio and sugar was significantly different (P < 0·05). Moisture content of pulp/texture of pulp, texture of pulp/sugar content of pulp and texture of pulp/ripening stages were negatively correlated, while pulp/peel ratio and moisture content of pulp were positively correlated. Chips packed in 80 μm high-density polyethylene pouches and stored at various relative humidities had extended shelf-life compared with the low-density polyethylene packed chips stored at the same relative humidities. This was due to the inadequacy of the low-density polyethylene in giving the required protection against moisture transmission thereby resulting in soggy chips in shorter periods. The implication of the findings on the formulation of a guideline for the processing of a good-quality plantain chips for the marketing system is discussed.  相似文献   
37.
The paper examines the performance of Modified Manchester (MM) modulation scheme over wavelength division multiplexing (WDM) in high-speed optical communication links. The MM as a new modulation technique has a narrow spectral width compared to conventional Manchester coding, which allows its implementation in WDM systems beneficial. In this study, the performance characteristics of MM and conventional Manchester modulation formats are assessed in WDM system at 10 Gb/s bitrate for each channel, for the least allowable channel spacing as well as tolerance to chromatic dispersion (CD). It is revealed from the results of simulation that MM performs meaningfully well in comparison with conventional Manchester in terms of tolerance against narrow optical filtering, spectral efficiency, which is improved by 32% and CD tolerance, which is improved by +100 ps/nm. Sixteen wavelength channels (16 × 10 Gb/s) are modulated to provide 160 Gb/s data capacity, which was transmitted successfully over 224 km standard single mode fibre (SSMF) using MM while the conventional Manchester only covered about 157 km.  相似文献   
38.
Binary discontinuous compact protein domains   总被引:6,自引:0,他引:6  
Few methods exist that identify discontinuous protein domainscontaining more than one polypeptide chain. This paper describesa new method for locating such discontinuous domains based ontheir compactness, and applies the methodology to locate themost compact domains in bovine pancreatic trypsin inhibitor,ribonuclease, cytochrome c and myoglobin. The compactness ofall binary discontinuous peptide combinations is first exhaustivelyevaluated. Several screening steps are then used to locate thosecompact units that represent global minima of compactness. Sincedomains are generally taken to be large, mutually exclusivestructures that span most of the protein's sequence, compactdomains were found by examining all compact units (both continuousand discontinuous) to locate two or three units that span mostof the protein's sequence, have little mutual overlap and goodoverall compactness. Compact domains compare well with domainsfound by other methods and with experimental evidence that maydifferentiate domain structure. The strongest experimental evidencefor the existence of compact discontinuous domains comes fromthe work of Oas and Kim [(1988) Nature, 336, 42–48] wherea peptide that corresponds almost exactly to a compact domainhas been synthesized and shown to have native-like structurein solution.  相似文献   
39.
In this study, we evaluated the effect of ultraviolet/ozone treatments for different times on the characteristics of wool fabrics with respect to wettability, permeability, yellowness index, and weight loss. The beneficial effects of this treatment on dyeability, color parameters, light fastness characteristics, and the change in color difference after exposure of the treated dyed samples to artificial daylight for about 150 h was investigated. The results indicated that the improvement in wetting processes may have been due to to surface modifications; this meant that an increase in the amorphousity of the treated samples, the oxidation of the cystine linkage on the surface of the fabrics, and the formation of free‐radical species encouraged dye penetration and aggregation inside the fiber pores as well as bond formation. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 90: 3668–3675, 2003  相似文献   
40.
Twenty-six market samples and four laboratory-prepared samples of “ogiri” were screened for aflatoxin contamination. Aflatoxins were not detected in any of the samples. The fermented product (ogiri) was prepared with Aspergillus flavus contaminated melon seeds. Losses of 64.7% aflatoxin B1 and 82.9% aflatoxin G1 were observed at the end of the third day of fermentation of the ground melon seeds. The samples were completely detoxified at the fourth day of fermentation. Increase in pH of the mash from 6.2 to 7.2 was observed during fermentation.  相似文献   
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