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61.
J.W. Marion  S. Lemeshow 《Water research》2010,44(16):4796-4804
Recent epidemiology studies examining U.S. recreational water exposure and illness relationships have focused primarily on coastal and Great Lakes beaches. Human-made lakes in the U.S. have received little attention in epidemiology studies despite contributing to more waterborne disease epidemics annually than coastal U.S. waters. In a comprehensive beach cohort study, we examined relationships between water quality indicators and reported adverse health outcomes among users of a beach at an inland U.S. lake. Human health data was collected over 26 swimming days during the 2009 swimming season in conjunction with water quality measurements. Adverse health outcomes were reported 8-9 days post-exposure via a phone survey. Wading, playing or swimming in the water was observed to be a significant risk factor for GI illness (adjusted odds ratio (AOR) of 3.2; CI 1.1, 9.0). Among water users, Escherichia coli density was significantly associated with elevated GI illness risk where the highest E. coli quartile was associated with an AOR of 7.0 (CI 1.5, 32). GI illness associations are consistent with previous freshwater epidemiology studies. Our findings are unique in that our observations of positive associations with GI illness risk are based upon a single daily E. coli measurement. Lastly, this study focused on an understudied issue, illness risk at inland reservoirs. Our results support the usefulness of E. coli as a health-relevant indicator of water quality for this inland U.S. beach.  相似文献   
62.
The synthesis of the bis-cyclometalated complex [{Ir(μ-Cl)(ccpz)2}2] (1, cppz = 1-chloro-4-(4-chlorophenyl)-phthalazine) from hydrated iridium(III) chloride and the ligand ccpz in refluxing ethoxyethanol is described. Compound 1 was characterized by spectroscopic means and the crystal structure was determined by X-ray crystallography. The absorption and emission spectra exhibit the new compound as a red-emitting phosphorescent complex.  相似文献   
63.
Hepatitis C (HCV) is a serious infection caused by a blood-borne virus. It is a contagious disease spreading via a variety of transmission mechanisms including contaminated tattoo equipment. Effectively regulating commercial tattoo parlours can greatly reduce this risk. This paper models the cost-effectiveness and optimal timing of such interventions, and parameterises the model with data for Vienna, Austria. This dynamic model of the contagious spread of HCV via tattooing and other mechanisms accounts for secondary infections and shows that regulating tattoo parlours as done in Vienna, Austria in 2003, is a cost-saving intervention.  相似文献   
64.
41 women with bulimia nervosa completed a brief intervention that was designed to promote symptom management. Cutoff scores for the determination of reliable and clinically significant change were calculated for several psychometric instruments that are commonly used as outcome measures in the field of eating disorders. Using these statistical procedures to assess therapeutic change, this study documents the diversity of outcomes that individuals reported following their participation in the intervention. As expected, there was a differential reporting of clinically significant change in favor of specific eating psychopathology relative to personality features and associated psychopathology. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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66.
The purpose of this paper is to present part of a computer aided design model which was developed for the analysis of millimeter wave rectangular waveguide circuits. This paper focuses on cap resonator circuits and pre-tuned modules for Gunn andimpatt oscillators in the W band. The theoretical results were verified through comparisons with experiments performed in the Ku band. The influence of the main cap circuit parameters are analyzed in order to provide a guidance for theptm design.  相似文献   
67.
For open car park structures, adopting a performance-based structural fire design is often justified and allowed because the fire does not reach flashover. However, this design approach requires an accurate assessment of temperatures in structural members exposed to car fires. This paper describes a numerical study on the thermal exposure on steel framing members in open car park fires. Steel temperatures are computed by the coupling of computational fluid dynamics and finite element modeling, and by analytical models from the Eurocodes. In addition, the influence of galvanization on the steel temperature evolution is assessed. Results show that temperatures in unprotected beams and columns are influenced by the section geometry, car fire scenario, modeling approach, and use of galvanization. Galvanization slightly delays and reduces peak temperature. Regarding the different models, CFD-FEM (CFD: computational fluid dynamics, FEM: finite-element method) coupled models predict lower temperatures than the Hasemi model, because the latter conservatively assumes that the fire flame continuously touches the ceiling. Further, the Hasemi model cannot account for the effect of reduced emissivity from galvanization on the absorbed heat flux. Detailed temperature distributions obtained in the steel members can be used to complete efficient structural fire designs based on the member sections, structure layout, and use of galvanization.  相似文献   
68.
Flow patterns in the course of transesterification of waste cooking oil (WCO), sunflower oil (SFO) with water and/or oleic acid as a model of WCO, and pure SFO in the presence of a KOH catalyst in microtubes were investigated. FAME yield for the transesterification of WCO reached more than 89% in the microtube reactors with a residence time of 252 s at 333 K. The flow patterns when using WCO were changed from a liquid–liquid slug flow at the inlet region to a parallel flow at the middle region, and then to a homogeneous liquid flow at the outlet region as the reaction proceeded at 333 K. Fine droplets containing glycerol and methanol generally formed in oil slugs when using pure SFO, but were almost unobservable when using WCO. The soap produced from free fatty acids was considered to be the main factor affecting the flow patterns of WCO and SFO. © 2009 American Institute of Chemical Engineers AIChE J, 2010  相似文献   
69.
Carbohydrates are ubiquitous and range from simple monosaccharides to large complex polysaccharides. Organic acids are compounds with acidic properties. Both occur naturally in many foods and in fermented products. Organic acids are usually derived from the hydrolysis of carbohydrates by microorganisms such as lactic acid bacteria. These bacteria convert carbohydrates into energy required for growth, since they are not equipped with the enzymes necessary for respiration and are unable to perform oxidative phosphorylation. Determination of carbohydrates and organic acids in foods of animal origin is important, since they contribute to flavor and texture. Their presence and proportions can affect the chemical and sensory characteristics of a food matrix and they can provide information on nutritional properties of food and the means to optimize selected technological processes. Furthermore, the levels of carbohydrate and organic acid are important to monitor bacterial growth and activity. Actually, these compounds can be quantified by several methods including high‐performance liquid chromatography (HPLC) and gas chromatography (GC). High‐performance liquid chromatography has been widely used to analyze carbohydrates and nonvolatile organic acids, while gas chromatography has been used to determine the volatile organic acids in complex matrices. This contribution provides an overview of chromatographic methods (HPLC and GC) used to analyze carbohydrates and organic acids in foods of animal origin.  相似文献   
70.
    
The quality of an -tocopherol standard can be checked easily by measuring the UV absorbance at minimum (255 nm,A min) and maximum (292 nm,A max) wavelengths inn-hexane. If the quotientA min/A max exceeds 0.18, the standard contains less than 90% -tocopherol and the determination at 292 nm will yield inaccurate results.  相似文献   
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