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51.
The association of socioeconomic variables with poor health status has been widely observed, if not well understood, and cultural dimensions of socioeconomic differences have rarely been incorporated into research models. In this article, a cultural dimension of socioeconomic status is examined in a Brazilian city through the use of ethnographic and social survey techniques. It suggests that lifestyle, defined in terms of the relative ability to accumulate consumer goods and the adoption of associated behaviors, is an important component of socioeconomic differences. Further research using cultural consensus analysis, a structured ethnographic technique that may be used to study shared cultural knowledge, demonstrates significant consensus regarding the definition of the successful lifestyle. Then, using that culturally defined model of the successful lifestyle as the central tendency, an individual-level measure of approximation to that lifestyle was developed for a representative sample of 250 persons. This culturally defined measure of lifestyle was inversely associated with arterial blood pressure (beta = -.216, p < .01), depressive symptoms (beta = -.236, p < .01), and globally perceived stress (beta = -.358, p < .01); furthermore, it absorbed the explained variability in these outcomes that is associated with conventional socioeconomic variables (occupation, education, income). For arterial pressure, cultural consonance explained almost 10 percent of the differences in blood pressure between individuals; for the psychological outcome variables, cultural consonance explained between 10 percent and 20 percent of the differences between individuals. Finally, its statistical effects were independent of other socioeconomic, dietary, anthropometric, and psychosocial variables. These results suggest that an individual's approximation to the cultural ideal of lifestyle, his or her "cultural consonance," mediates the observed effects of socioeconomic variables on health status.  相似文献   
52.
We describe a programming scheme for massively distributed systems that are assumed to self-organize according to a given set of simple rules. The focus of this investigation is operation and control in sensor and actor networks (SANETs). The main issues addressed by self-organization techniques are scalability, network lifetime, and real-time support. In the literature, biological principles are often cited as inspirations for technical solutions, especially in the domain of self-organization. We developed a system named rule-based sensor network (RSN) according to the observed communication and control behavior in cellular communication. Cellular signaling cascades allow the event-specific reaction initiated by individual cells in collaboration with their direct neighbors. Information between cells are transmitted via proteins and result in the cascade of protein–protein or protein–DNA interactions to produce a specific cellular answer, e.g. the activation of cells or the transmission of mediators. These processes are programmed in every individual cell and lead to a coordinated reaction on a higher organization platform. We transferred these mechanisms to operation and control in SANETs. In particular, a rule-based processing scheme relying on the main concepts of cellular signaling cascades has been developed. It relies on simple local rules and provides problem specific reaction such as local actuation control and data manipulation. We describe this RSN technology and demonstrate comparative simulation results that show the feasibility of our approach.  相似文献   
53.
X-ray powder diffraction methods of phase quantification were adapted and compared to mixtures of -Si3N4 and -SiC. Multiline mean-normalized-intensity methods and whole pattern analysis (Rietveld) both have advantages and disadvantages over each other. Satisfactory results (less than 3% absolute deviation) can be achieved in minimal time using intensity normalization methods. Phase quantification using the Rietveld method requires significantly longer measuring time, evaluation time and expertise to obtain the same results.  相似文献   
54.
CombiTool is a new computer program for the analysis of combination effects of biologically active agents. It performs model calculations and an analysis of experimental combination effects for two or three agents according to both the Bliss independence and the Loewe additivity criteria. Zero interaction response surfaces are calculated from single-agent dose-response relations and compared to experimental combination data. The calculation of response surfaces for Loewe additivity is based on a new approach which combines the implicit definition equation in terms of doses alone with single-agent dose-response relations. The simultaneous analysis of experimental data according to both Loewe additivity and Bliss independence within one program can hopefully contribute to a better understanding of the meaning and limits of the two criteria. CombiTool has a built-in graphics facility which allows the direct visualization of the response surfaces or the corresponding contour plots and the experimental data.  相似文献   
55.
In this short review we present recent experiments which can be used to infer the structural parameters of ultrathin polyimide and polyamide acid films as a function of distance from the substrate surface. The polyimide films are prepared by the Langmuir-Blodgett technique in a layer-by-layer fashion, and the orientation of the pyromellitic imide unit in the polyimide macromolecules is determined as a function of film thickness by Near Edge X-ray Absorption Fine Structure (NEXAFS) spectroscopy. Subsequent delamination experiments on these Langmuir-Blodgett (LG) deposited polyimide films reveal that the locus of failure does not occur in a “weak boundary-layer” adjacent to the silicon substrate as expected from delamination experiments with macroscopically thick films.

As a non-destructive method to study the orientation of polymer molecules during film growth, second harmonic generation (SHG) experiments on the deposition of polyamide acid (PAA) on gold and silver surfaces will be briefly described. In this particular case, the experiments reveal an influence on the interfacial chemical bond on the film structure up to a total thickness of 60-100 mm.  相似文献   
56.
De novo Parkinson's disease (PD) patients identified presence or absence of a unique shape presented with homogeneous distractors. Response time (RT) was examined as a function of prior experience with target and/or distractor assessing latent inhibition (LI; slower RTs to a target that was formerly a distractor against a background of distractors that were formerly targets as compared with a novel target with distractors that were formerly targets) and novel pop-out effects. PD patients were slower than controls in detecting test-phase targets compared with preexposure-phase targets. Female PD patients with right-side motor symptoms had elevated LI compared with female controls and female PD patients with left-side symptoms. Male PD patients with right-side symptoms did not exhibit LI. Results are discussed in terms of the dopamine hypothesis and the reciprocal relationship between PD and schizophrenia. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
57.
(1) Adipsin is an adipokine that may link increased fat mass and adipose tissue dysfunction to obesity-related cardiometabolic diseases. Here, we investigated whether adipsin serum concentrations and adipose tissue (AT) adipsin mRNA expression are related to parameters of AT function, obesity and type 2 diabetes (T2D). (2) Methods: A cohort of 637 individuals with a wide range of age and body weight (Age: 18–85 years; BMI: 19–70 kg/m2) with (n = 237) or without (n = 400) T2D was analyzed for serum adipsin concentrations by ELISA and visceral (VAT) and subcutaneous (SAT) adipsin mRNA expression by RT-PCR. (3) Results: Adipsin serum concentrations were significantly higher in patients with T2D compared to normoglycemic individuals. We found significant positive univariate relationships of adipsin serum concentrations with age (r = 0.282, p < 0.001), body weight (r = 0.264, p < 0.001), fasting plasma glucose (r = 0.136, p = 0.006) and leptin serum concentrations (r = 0.362, p < 0.001). Neither VAT nor SAT adipsin mRNA expression correlated with adipsin serum concentrations after adjusting for age, sex and BMI. Independent of T2D status, we found significantly higher adipsin expression in SAT compared to VAT (4) Conclusions: Our data suggest that adipsin serum concentrations are strongly related to obesity and age. However, neither circulating adipsin nor adipsin AT expression reflects parameters of impaired glucose or lipid metabolism in patients with obesity with or without T2D.  相似文献   
58.
59.
In reliability analyses of safety‐relevant components it is necessary to consider the variations in load, geometry and material properties. The scatter in load, geometry and global material properties is nowadays addressed in some stochastic analyses [ 1 , 2 ], whereas the scatter in local material properties is not adequately regarded due to difficulties in determining meaningful and stochastically relevant local material properties. In this paper a method for estimating the local distribution of the effective elastic behavior, belonging to a defined component direction, is presented. First, electron backscatter diffraction (EBSD) analyses of relevant cross sections were performed. Second, the effective elastic behavior perpendicular to the cross section was calculated for each scan point from the determined Euler angles. By using direct tensor rotation and generalized Hooke's law, the method can be applied to all kind of crystal structures if the elastic constants of the single crystal material are known. The experimental procedure, the mathematical background und the numerical realization are described in detail. Two examples of applying the procedure to materials for aerospace components as well as a stochastic finite element simulation considering the determined scatter of the elastic properties are shown.  相似文献   
60.
Lead content of dietary calcium supplements available in Brazil.   总被引:1,自引:0,他引:1  
The lead and calcium content of calcium supplements available in Brazil were determined by graphite furnace and flame atomic absorption spectrometry, respectively. Samples were microwave-digested in concentrated HNO(3). Citric acid was used as a chemical modifier in the lead analysis. Supplements were classified into six categories: oyster industrialized (OI, n=4), oyster prepared in pharmacy (OP, n=3), refined industrialized (RI, n=6), refined prepared in pharmacy (RP, n=3), bone meal (B, n=3), and dolomite (D, n=4). Lead levels (microg g(-1) of measured calcium) were higher in D products (2.33), followed by OI, RP, OP, and RI products (1.46, 1.32, 1.29, 0.75), while B products had levels lower than the limit of quantification (0.02 microg g(-1) unit weight). Daily lead intake of eight supplements exceeded the limit of California, USA (1.5 microg g(-1) calcium), but none exceeded the federal limit of USA (7.5 microg g(-1) calcium) or the provisional tolerable lead intake by FAO/WHO (25 microg kg(-1) per week).  相似文献   
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