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101.
Considerable debate exists regarding the possible relationship between child abuse and posttraumatic stress disorder (PTSD). In this study, 3 groups of foster care children were compared. The groups included 50 sexually abused, 50 physically abused, and 50 nonabused foster care children. Participants completed the Child Post-Traumatic Stress Reaction Index, the Childhood PTSD Interview, and the Modified Stroop Procedure (MSP), which included sexual abuse and nonsexual abuse stimuli. The MSP has not been previously used in child abuse research. Results indicated that sexually and physically abused children demonstrated PTSD at a high level. The MSP discriminated between the sexually abused children with PTSD and those without PTSD. Responses to the MSP sexual abuse stimuli resulted in significantly longer color-naming times than responses to nonsexual abuse stimuli. Preadolescents demonstrated more severe PTSD than early adolescent children. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
102.
The serum T3, T4 and TSH concentrations were assessed by RIA method in 25 (14 females, 11 males) long-term treated (mean treatment duration 12.8 years) epileptic patients. The mean serum T3, T4 and TSH levels were lower than in control group according to clinical picture of epilepsy and treatment applied. The lowest mean serum TSH concentration was in patients with known aetiology of epilepsy. Patients with tonic-clonic seizures had lower serum levels of all hormones measured in comparison with the patients with partial seizures. Mean serum T3, T4 and TSH levels were low in patient group receiving valproic acid. The lowest mean TSH serum concentration as compared to control group was in the patients treated with phenytoin. None of the epileptic patients developed clinical symptoms of hypothyreoidism.  相似文献   
103.
The analytical performance and practicability of the Boehringer Mannheim (BM)/Hitachi 911 analysis system have been assessed in a multicentre evaluation, which involved six laboratories from European countries. Analytes commonly used in classical clinical chemistry were tested in a core programme, which mainly followed the ECCLS guidelines. In addition, a satellite programme covered other analytes, such as proteins, drugs and urine analytes. In total, the study comprised more than 100 000 data items collected over a three-month period. The evaluation was supported with ‘Computer Aided Evaluation’ (CAEv) and telecommunications.Acceptance criteria for the results were established at the beginning of the study. Nearly all of the analytes met the imprecision limits: within-run imprecision (as CVs) was 2% for enzyme and substrate assays, 1% for ISE methods and 5% for immunoassays; between-day imprecision was 3l% for enzyme and substrate assays, 2% for ISE methods and 10% for immunoassays.No relevant drift effects (systematic deviation ≥ 3%) were observed over eight hours. The methods were linear over a wide range. Sample-related and reagent-dependent carry-over can be reduced to a negligible amount by integration of a softwarecontrolled wash-step.Endogenous interferences were found for creatinine (Jaffé method) and uric acid assays (caused by bilirubin), for creatine kinase, creatine kinase MB isoform and γ-glutamyltransferase (caused by haemoglobin), and for immunoglobulin A (caused by lipaemia)Accuracy was checked by an interlaboratory survey, recovery studies in control materials and method comparison studies. The survey showed that, with the exception of cholesterol and iron in two laboratories, the recovery of analytes did not deviate by more than 5%. Sixty-six of the 77 method comparisons performed met the acceptance criteria. The deviations of the remaining 11 results could be explained by differences in either calibration, application or by the use of different methods.Practicability was assessed using a questionnaire which covered all of the important aspects of an analysis system in the clinical laboratory. Twelve groups of attributes out of 14 were rater higher for the BM/Hitachi 911 than for the present situation in the laboratories concerned. Especially high scores were given for the versatility group.The acceptance criteria for the analytical performance of the BM/Hitachi 911 analysis system were fulfilled in all laboratory segments with few exceptions. The practicability exceeded the requirements in most of the attributes. The results of the study confirmed the usefulness of the system as a consolidated workstation in small- to medium-sized clinical laboratories and in STAT laboratories, or as an instrument for special analytes like proteins and drugs, or for urinalysis in large laboratories.  相似文献   
104.
Experiments have been performed to examine the ductility of Zircaloy 4 cladding tubes under conditions of near plane-strain deformation in the hoop direction (transverse to the tube axis) at temperatures of 25 and 300°C and at strain rates of 10−3 and 102 s−1. To conduct these experiments, a specimen configuration was designed in which near plane-strain deformation is achieved, and a test methodology was established to determine two failure conditions: the limit strain at the onset of localized necking and the fracture strain. Experiments performed on cold-worked stress relieved material using the transverse plane-strain specimen geometry indicate major differences in failure behavior from that observed in uniaxial tension, although both test conditions result in failure by a localized necking process. The experimental results also indicate that while plane-strain fracture strains increase with temperature between 25 and 300°C, at a given temperature they are insensitive to strain rate. The limit strains at localized necking also increase with temperature but only at the high 102 s−1 strain rate. Finally, the failure data indicate a strong sensitivity to surface flaws, as predicted by localized necking theory.  相似文献   
105.
S. Motta  J. Wick 《Computing》1991,46(3):223-232
We present first results of a numerical method solving inhomogeneous partial differential equation of first order with a conservation property. The method is based on the Finite Particle Schemes for homogeneous PDE's of the first order as the Vlasov-Poisson system in kinetic theory. The inhomogeneity is redefined as a flux. For the associated ‘velocity-field’ given by the Radon-Nikodym derivative of the flux, we give a numerical approximation. Together with the ‘velocity-field’ given, by the derivative terms of first order this gives the right hand side of the equations of motion of the particles. The computation can be done in a very efficient way and the results are in good agreement with the exact solution.  相似文献   
106.
We previously reported that complexes of peptide with soluble single-chain recombinant MHC (SC-MHC) class I molecules are able to induce cytotoxic T lymphocytes (CTL) in vitro in a murine system with an efficiency comparable to that observed with peptide-pulsed dendritic cells as antigen-presenting cells. In this report, we have assessed the capacity of preformed peptide/SC-Kd complexes in monomeric or dimeric form as well as of peptide/SC-Kd-loaded beads to generate in vitro specific CTL responses from naive DBA/2 spleen cells. Peptide/SC-Kd-coated beads were consistently more efficient. We evaluated the role of costimulatory molecules, using monoclonal antibodies anti-CD80 or anti-CD86. In addition, the capacity of peptide/SC-Kd-coated beads to generate a CTL response from purified naive CD8+ T cells was ascertained. Taken together, the results indicate that, under our conditions, CTL priming does not require the participation of co-stimulatory molecules and is the consequence of a direct interaction between the cognate TCR on peptide-specific CTL precursors and the peptide/SC-Kd-loaded beads. Titration of the amount of preformed complexes of SC-Kd and peptide 170-179 of HLA-CW3 that need to be coated onto the beads to prime CTL precursors shows an activation threshold which can be calculated to be between 25000 and 50000 complexes. In effect, in cultures stimulated with specific peptide CW3/SC-Kd complexes representing less than 50% occupancy of the total (10(5)) complexes on the beads, no peptide-specific cytolytic activity was observed. These results suggest that the efficiency of the primary CTL induction depends on the density of specific peptide/SC-Kd complexes present on the beads.  相似文献   
107.
The objective of the present work was to evaluate the influence of the welding parameters in the formation of defects in weld overlays with nickel-based alloys, and its possible elimination through the correct adjustment of the welding parameters. Coatings were deposited with the nickel-based alloy types Inconel 625, Hastelloy C276 and Inconel 686 on C–Mn steel plates, using GTAW cold wire feed process. The planning of the experiments was accomplished by applying the Taguchi method. The control factors evaluated were the energy technique (ET), the welding heat input (E), the type of alloy (L), the shielding gas (G) and the type of arc oscillation (T). Other parameters were maintained constant, having previously been investigated. The results showed that the arc oscillation type is spiral; although it contributes significantly to reduce the dilution level, it causes a strong instability to the process, resulting in most of the cases in surface defects or defects among passes. The optimum condition to avoid defects among passes was identified by the Taguchi method, which was constituted by the following combination of control factors: 2-2-2-3-3, or by: I energy technique (TE-I); medium heat input level (Emedium); Hastelloy C276 alloy; shielding gas Ar + He; double-8 arc oscillation. The optimum condition for the welding without defects results in high dilution level not being indicated for the welding of resistant coverings to the corrosion.  相似文献   
108.
The simple way to prepare In2O3 microcrystals is reported in this paper. The precursor, In(OH)3 microstructures, were obtained using the Microwave-Assisted Hydrothermal (MAH) Method. By annealing as-prepared In(OH)3 precursor at 500 °C for 5 min in a domestic microwave oven (MO), In2O3 microcrystals were prepared, inheriting the morphology of their precursor while still slightly distorted and collapsed due to the In(OH)3 dehydration process which was studied by thermal analysis. The In(OH)3 and In2O3 were characterized using powder X-ray diffraction (XRD), field emission scanning electron microscopy (FE-SEM) and Raman spectroscopy. These techniques confirm the chemical dehydration of In(OH)3 and the formation of In2O3 powders. The domestic MO promotes a rapid structural organization as compared with a CF (conventional furnace). The MAH method and the subsequent annealing in a domestic MO were shown to be a low cost route for the production of In2O3, with the advantages of lower temperature and smaller time.  相似文献   
109.
Surface microorganisms contribute to the ripening of some low-moisture cheese varieties and the composition of the surface microflora is dynamic. Brevibacterium linens is an important surface microorganism that is present in the smear of surface-ripened cheeses and is commonly regarded as the organism primarily responsible for the characteristic taste, aroma, and color of surface cheese. The enzymology and biochemical characteristics of B. linens influence the ripening and final characteristics of smear surface-ripened cheeses. Proteolytic, peptidolytic, esterolytic, and lipolytic activities are of particular importance in the ripening process. Because of its putative importance to the ripening in smear-ripened cheeses, B. linens is the best studied component of the microflora, although in comparision with other dairy-related microorganisms, it is poorly characterized. B. linens produces antimicrobial substances that inhibit the growth of many food poisoning bacteria as well as several yeast and moulds. Some inhibitory substances produced by this species were identified as bacteriocins. Bacteriocins could appear as potential agents to be applied in food conservation systems in order to provide microbiologically stable foods. This article describes the properties of B. linens and discusses about the potential of this species to produce bacteriocins and other antimicrobial substances, which are important for production of high quality cheese.  相似文献   
110.
Scientific and other non-patent references (NPRs) in patents are important tools to analyze interactions between science and technology. This paper organizes a database with 514,894 USPTO patents granted globally in 1974, 1982, 1990, 1998 and 2006. There are 165,762 patents with at least one reference to science and engineering (S&E) literature, from a total of 1,375,503 references. Through a lexical analysis, 71.1% of this S&E literature is classified by S&E fields. These data serve as the basis for the elaboration of global and national 3-dimensional matrices (technological domains, S&E fields and number of references). Three indicators are proposed to analyze these matrices, allowing us to identify patterns of structured growth that differentiate developed and non-developed countries. This differentiation informs suggestions for public policies for development, emphasizing the need for an articulation between the industrial and technological dimension and scientific side. The intertwinement of these two dimensions is a key component of developmental policies for the twenty-first century.  相似文献   
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