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1.
Since 2005, all fatal road traffic crashes in Norway have been analyzed in-depth by multidisciplinary investigation teams organized by the Norwegian Public Roads Administration (NPRA). During the period 2005–2010, 608 drivers of cars or vans were killed in road traffic crashes. Blood samples were collected from 372 (61%) of the drivers and analyzed for alcohol and a large number of psychoactive drugs at the Norwegian Institute of Public Health (NIPH). After coupling the analytical results with the NPRA crash database, 369 drivers with a fatal outcome were identified and included. Alcohol or drug concentrations in blood above the legal limits were found in 39.8% of the drivers who were investigated for alcohol or drug impairment; 33.9% had blood alcohol concentrations above 0.5 g/L or concentrations of drugs above the equivalent Norwegian legal impairment limits or concentrations of amphetamines above 200 μg/L. Among drivers with a fatal outcome who had been impaired by alcohol or drugs, 64.6% were unbelted and 71.7% were speeding when the crash occurred; whereas 24.2% and 33.2% of the sober drivers were unbelted or speeding, respectively. Statistically significant associations were found between impairment by alcohol or amphetamines and driving unbelted or speeding. Excessive speeding is one of the main reasons for road traffic crashes and together with being unbelted the main reasons for a fatal outcome. This behavior might in many cases be due to increased risk-taking or negligence of safety measures as a result of alcohol or drug use.  相似文献   
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OBJECTIVES: The benefit of mammography depends on repeated use. Therefore, surveying the mammographic quality as judged by the users addresses an important topic. The authors assess the practicality, validity, reliability, and discriminatory power of a new, brief, multidimensional questionnaire for measuring patient satisfaction with mammography. Items measuring discomfort and attitudes toward repeat adherence were included. METHODS: A self-administered questionnaire was given to women from six radiology departments in Norway. Four hundred eighty-eight out of 550 women referred for screening or diagnostic mammography were included. Seventy-seven patients also completed the test/retest study, and 44 women additionally completed an Australian questionnaire. Scores for patient satisfaction on the structure, process, discomfort, and general satisfaction scales of the questionnaire were used as the main outcome measures. RESULTS: Response rate was 89%, and rate of completion was more than 95%. Strict psychometric criteria for construct validity and reliability were satisfied. Because lower levels of satisfaction were detectable with the new questionnaire but not with the Australian questionnaire and because an acceptable degree of variability in response was detected, support for discriminatory power was found. CONCLUSIONS: The discomfort dimension contributed substantially to validity and discriminatory power. Patient behavior with time may be monitored with the new questionnaire, thus representing a valuable tool for scientific and practical purposes.  相似文献   
3.
A case–control study was conducted on 204 drivers fatally injured in road traffic accidents in south-eastern Norway during the period 2003–2008. Cases from single vehicle accidents (N = 68) were assessed separately. As controls, 10 540 drivers selected in a roadside survey in the same geographical area during 2005–2006 were used. Blood samples were collected from the cases and oral fluid (saliva) samples from the controls. Samples were analysed for alcohol, amphetamines, cannabis, cocaine, opioid analgesics, hypnotics, sedatives and a muscle relaxant; altogether 22 psychoactive substances. Equivalent cutoff concentrations for blood and oral fluid were used. The risk for fatal injury in a road traffic accident was estimated using logistic regression adjusting for gender, age, season of the year, and time of the week. The odds for involvement in fatal road traffic accidents for different substances or combination of substances were in increasing order: single drug < multiple drugs < alcohol only < alcohol + drugs. For single substance use: medicinal drug or THC < amphetamine/methamphetamine < alcohol. For most substances, higher ORs were found when studying drivers involved in single vehicle accidents than for those involved in multiple vehicle accidents, but confidence intervals were wider.  相似文献   
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Differential enthalpies of absorption of CO2 in aqueous solutions of 2-aminoethanol (MEA) and N-methyldiethanolamine were predicted from reaction equilibrium constants using the Gibbs-Helmholtz equation. Correlations for the reaction equilibrium constants and enthalpies of reaction found in the literature for each of the individual reactions taking place at CO2 absorption were compared to experimental data, and from this, a set of equations was selected for the Deshmukh-Mather model in this work. The carbamate dissociation constant for MEA was fitted to experimental PCO2 and ΔHabs data. Heat contributions from each of the individual reactions taking place in the systems MEA+H2O+CO2 and MDEA+H2O+CO2 were calculated and presented as functions of loading and temperature. Predicted enthalpies of absorption agree well with the data from literature and with experimental data from this work. The calculation procedure described in this work may be used for the adjustment of reaction equilibrium constants by fitting the equilibrium model also to experimentally measured heats of absorption data in addition to PCO2 data.  相似文献   
7.
The exact prediction of the flow structure in bubble columns is important for their design and scale-up. This paper proposes a theoretical model for the liquid circulation on the basis of Reynolds equation of motion and the eddy viscosity distribution of single phase pipe flow, and presents a derivation of an analytical equation for the axial liquid velocity profiles that is fast and easy to use. The model shows a strong analogy for the eddy viscosity between multiphase and single-phase systems, and how both eddy and molecular viscosities affect the flow. The velocity profiles calculated from the model are shown to agree well with reported experimental data for both low and high viscosity fluids.  相似文献   
8.
The liquid film thickness and hydrodynamic entrance length in a vertical tube was studied experimentally and numerically. Measurements using distilled water, 30 wt % MEA and 40 wt % sugar solutions were carried out to investigate the effects of liquid flow rate on the formation of the liquid film. The experimental results validate the new Navier‐Stokes based equation in cylindrical coordinates (Eq. 16) and the volume of fluid (VOF) model giving a competitively high prediction of the liquid film thickness especially in the low Reynolds number region. In addition, a new empirical model and an improved minimal surface model have been first proposed for calculation of the hydrodynamic entrance length, with a relatively reasonable average absolute relative deviation (AARD) of 3.03% and 6.83%, respectively. Furthermore, the effects of the hydrodynamic entry length on the gas–liquid interfacial area calculated by the improved minimal surface model were comprehensively studied, and can be ignored if the ratio of the liquid film length (y) and the hydrodynamic entrance length (λE) is lower than 10. However, it should be noted that the hydrodynamic entrance length cannot be ignored in packed columns in which the liquid flow is very complex due to the packings with different structures and materials. © 2018 American Institute of Chemical Engineers AIChE J, 64: 2078–2088, 2018  相似文献   
9.
A total of 190 patients, referred by general practitioners for a double-contrast barium enema, were subsequently examined with colonoscopy. With colonoscopy and histology as the reference standard, sensitivity, specificity, positive and negative predictive values, and accuracy for the radiological detection of cancer and polyps were calculated. No cancer was overlooked by the radiological examination, but there were four false positives. The overall sensitivity for polyps was 70%, increasing to 81% for polyps > or = 10 mm. The predictive value was 93-97% for the exclusion of polyps. The caecum was reached in 187 patients by double-contrast barium enema (98%) and in 164 patients (86%) by colonoscopy. Lesions in four of 12 patients who had radiological changes were undetected at the first colonoscopy, but a repeat examination showed polyps > or = 10 mm in size. Although colonoscopy is a more sensitive technique for the detection of small mucosal lesions, the general practitioners may, in the vast majority of patients, rely on a negative result for polyps and cancer obtained by the double-contrast barium enema. The latter is linked with a number of false-positive cases, while colonoscopy is associated with technical difficulties; both techniques may lead to repeated examinations, regardless of which was the first choice.  相似文献   
10.
The dimer of the hemoregulatory peptide HP5b has been investigated for biological effects on various cell types in culture including mouse granulocyte-macrophage colony forming units (CFU-GM) from agar and murine long-term bone marrow culture (LTBMC). While CFU-GM were significantly stimulated in both systems, mitogen activation of mouse T, B and natural killer (NK) cells was not affected. Peptide treated mouse 3T3 fibroblasts reached a higher saturation density than controls; otherwise no effect was seen. A series of malignant cell lines was also tested. On a human glioblastoma cell line (GaMg) and rat glioma cell line (BT5C) a slight but significant stimulatory effect was found, while human mammary carcinoma cells (MCF7) were not affected. On SC1 mouse lymphoma cells a slight stimulation of cell growth was seen during the first part of exponential growth. Since HP5b acts as a stimulator for stromal cell secretion of other growth factors, supernatants from a human bone marrow stromal cell line stimulated with HP5b were tested on various cell lines. The effects of the supernatants on cell growth of the tested cell lines were not affected by HP5b treatment. Taken together with available in vivo data, the results indicate that the hemoregulatory peptide is a selective stimulator of myelopoiesis.  相似文献   
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