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51.
The Allegheny County Neighborhood Preservation Program has generated over five million dollars worth of housing rehabilitation in the three years in which it has been operating. This article is an evaluation of Phase 1 of the program. It compares loan recipients and non-recipients in order to determine which of the program components are the most important, which factors influence a household's investment decision, and what effect investment has on the perceptions of residents regarding the quality of both housing and the neighborhood.  相似文献   
52.
HYPOTHESIZED THAT SS SCORING HIGH ON A DERIVED SCALE OF FEAR OF DEATH AND ILLNESS WOULD EXHIBIT MORE SIGNS OF BEHAVIOR DISRUPTION THAN SS SCORING LOW AFTER SEEING A FILM DESCRIBING THE EFFECTS OF FATAL DISEASE. 22 FEMALE SS WERE USED: 12 SCORING HIGH ON THE SCALE AND 10 SCORING LOW. 1/2 OF EACH GROUP SAW A THREATENING FILM, AND 1/2 SAW A NONTHREATENING EDUCATIONAL FILM. ALL SS TOOK THE DIGIT SYMBOL SUBTEST OF THE WECHSLER-BELLEVUE INTELLIGENCE SCALE BEFORE AND AFTER SEEING THE FILM. A SIGNIFICANT INTERACTION WAS OBTAINED BETWEEN FEAR AND STRESS FOR MOTOR ERRORS, BUT NOT FOR PERCEPTUAL ERRORS. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
53.
Phase equilibrium relations in the system CaO-Yb2O3 were studied. Results of this work demonstrated the existence of four crystalline phases: Yb2O3.3CaO, Yb2O3.2CaO, Yb2O3°CaO, and 2Yb2O3°CaO. The 2Yb2O3°CaO phase is metastable at all temperatures and was obtained only by rapid quenching from the melt. The crystalline solubility limit of YbaO3 in CaO at 1850°C is slightly greater than 8 mole %, whereas no solubility of CaO in Yb2O3 was detected. All four compounds have subsolidus minimums of stability and dissociate into the component oxides below 1800°C. Data are also presented for the systems CaO-Gd2O3 and CaO-La2O3.  相似文献   
54.
Steaks, fabricated from forequarters from field-slaughtered Alaskan reindeer, were prepared from meat flaked to two sizes (1.295 and 1.905 cm), with (0.5%) and without phosphate, and with (0.5%) and without salt. Phosphate did not appreciably affect sensory properties. Larger flakes and salt improved quality and acceptability, therefore, additional steaks were fabricated from meat flaked with a larger cutting head (4.064-cm) and with three levels of salt (0.0, 0.5 and 0.75%). Steaks containing 0.75% salt were less chewy, softer, juicier, and more acceptable than those made with 0.5% salt but did not differ from those containing no salt. Feasibility of producing restructured steaks from reindeer forequarters was demonstrated.  相似文献   
55.
Abstract Various aspects of soft paraffins, with the main emphasis on their rheological properties, are considered in a review of 119 references. Rheological test methods currently used are critically appraised in sections on penetrometry, continuous shear viscometry, oscillatory testing and creep analysis. The chemical nature, microscopic structure, miscellaneous methods of standardisation, formulation and work softening of petrolatums are reviewed. The textural properties of soft paraffins are discussed; a master curve of the rheological conditions operative during spreading on the skin is presented.  相似文献   
56.
Direct microscopic evidence is presented in support of an explanation of R -curve behavior in monophase ceramics by grain-localized bridging across the newly formed crack interface. In situ observations are made of crack growth in tapered cantilever beam and indented flexure specimens of a coarsegrained alumina. The fractures are observed to be highly stable, typical of a material with a strongly increasing resistance characteristic, but are discontinuous at the microstructural level. Associated with this discontinuity is the appearance of overlapping segments in the surface fracture trace around bridging grains; the mean spacing of such "activity sites" along the trace is about 2 to 5 grain diameters. These segments link up with the primary crack beneath the specimen surface, and continue to evolve toward rupture of the bridge as fracture proceeds. The bridges remain active at large distances, of order 100 grain diameters or more, behind the crack tip. Scanning electron microscopy of some of the bridging sites demonstrates that secondary (interface-adjacent) microfracture and frictional tractions are important elements in the bridge separation process. Evidence is sought, but none found, for some of the more popular alternative models of toughening, notably frontal-zone microcracking and cracktip/internal-stress interaction. It is suggested that the crackinterface bridging mechanism may be a general phenomenon in nontransforming ceramics.  相似文献   
57.
Representation poses important challenges to connectionism. The ability to compose representations structurally is critical in achieving the capability considered necessary for cognition. We are investigating distributed patterns that represent structure as part of a larger effort to develop a natural language processor. Recursive auto-associative memory (RAAM) representations show unusual promise as a general vehicle for representing classical symbolic structures in a way that supports compositionality. However, RAAMs are limited to representations for fixed-valence structures and can often be difficult to train. We provide a technique for mapping any ordered collection (forest) of hierarchical structures (trees) into a set of training patterns which can be used effectively in training a simple recurrent network (SRN) to develop RAAM-style distributed representations. The advantages in our technique are three-fold: first, the fixed-valence restriction on structures represented by patterns trained with RAAMs is removed; second, the representations resulting from training correspond to ordered forests of labeled trees, thereby extending what can be represented in this fashion; third, training can be accomplished with an auto-associative SRN, making training a much more straightforward process and one which optimally utilizes the n-dimensional space of patterns.  相似文献   
58.
Very high efficiencies have been demonstrated under concentration with silicon solar cells having interdigitated contacts on the backside. However, only laboratory cells of small dimension have reached very high efficiencies. The need for developing a multilevel metallization technology for back contact concentrator solar cells of large area is demonstrated. The particular features required for such a multilevel interconnection are studied and a process using anodic oxidation of aluminum is presented. Back contact silicon solar cells of 0.64 cm2 have been processed in this technology resulting in 26.2% efficiencies at 10W/cm2 (100 suns AM1.5, 25.5 °C). the highest efficiency reported to date for a solar cell of this area. The one-sun efficiency of this cell is 21.7% (AMI.5, 25.2°C). We propose also a new design for the metallization of back contact cells which allows an increase in the size of the cell without increasing the series resistance.  相似文献   
59.
The antimicrobial activity of sucrose and methylglucose esters of medium to long chain fatty acids was studied with two microorganisms involved in the spoilage of salad dressings, Zygosaccharomyces bailii and Lactobacillus fructivorans. The microorganisms were inhibited to various degrees by 0.1, 0.5, and 1.0% synthesized sucrose or methylglucose monoesters using a modified broth dilution method. Sucrose monoesters were most inhibitory when the esterified fatty acid was myristic (C14) or palmitic acid (C16). Methylglucose monoesters with lauric (C12) or myristic acid (C14) exhibited greater inhibition than those with longer chain fatty acids. The least inhibition was generally observed with sucrose and methylglucose oleate (C18:1). Sucrose monoesters were usually more inhibitory than methylglucose monoesters of the same fatty acid, especially for palmitic and stearic (C18) acids. In salad dressing, 1% sucrose monoesters of lauric, myristic, or palmitic acid significantly (P < 0.05) inhibited the growth of Z. bailii and L. fructivorans, and were comparable with or more effective than 0.1% sodium benzoate. Z. bailii growth was nearly completely inhibited by sucrose laurate, myristate and palmitate by 9 days of salad dressing storage. Sucrose monoesters did not delay the lag phase of L.  相似文献   
60.
ABSTRACT

Because of their speed and convenience, optical particle counters are widely used for particle size analysis of liquid samples. In some cases, both solid particles and emulsified water or oil may be present in a sample. Since emulsion droplets are counted as if they are solid particles, analysis and data interpretation for these samples are difficult. Until recently, no suitable method existed for distinguishing solid contaminants from emulsion droplets. This paper discusses a method which overcomes this limitation. Through the use of a surfactant-laden nonpolar dilution fluid, water is incorporated into reverse micelles too small to be seen by most optical particle counters. As a result, only solid contaminants are counted, and many problems associated with the analysis of emulsions are overcome. Results obtained from a wide range of oil and water emulsions are used to evaluate the merits and possible applications of the new technique.  相似文献   
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