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For about twenty years, prematurity has been the subject of many preventive actions. In spite of the elaboration of different screening programmes, preterm deliveries rate doesn't decrease. Some somatic risk factors are now known and are the subject of an unconditional screening in prenatal consultation. However we consider that the etiology of many preterm deliveries remain unknown and 55% of preterm cases could be idiopathic without any explanation of pathological order. The clinical observation suggests the existence of a link between preterm delivery and the psychosocial environment of the pregnant woman. According to that suggestion, they are now making a study in the university obstetrical service of the CHR Citadelle (Liège). The first part of the research has enabled to identify different risk factors such as: illegitimate pregnancy, future mother living alone, unemployed husband, no wage, stress, earlier miscarriage, social isolation, less than 2 years between 2 babies, bad satisfying pregnancy on a psychological and/or physical point of view. According to the study and literature results, a psychosocial risk screening overview has been elaborated. It would permit to identify the cases leading surely to a preterm delivery. That study is financed by a convention between the "Ministère de la Culture et des Affaires sociales de la Communauté fran?aise".  相似文献   
54.
The effects of applying gelatine (10%) and chitosan (1%) as spray coatings to extend the shelf life of vacuum-packaged beef was studied and compared against uncoated vacuum-packaged beef for up to 21 days. The impact of edible coatings on the water-holding properties of vacuum-packaged beef was investigated by LF-NMR together with physicochemical, microbiological and sensorial assessments. Chitosan coating significantly reduced lipid oxidation by ~30% to 36% and inhibited the growth of lactic acid bacteriaby ~ 1–2 log cfu compared to purge collected from uncoated and gelatine coated samples. It did not negatively affect the meat pH, tenderness and colour, and exhibited significantly higher sensorial acceptance compared to beef coated with gelatine. Both coatings were not effective in reducing purge loss in vacuum-packaged meat as the storage time increased. This study suggests that chitosan spray coating could be easily adapted to industrial plant settings as an antioxidant and antimicrobial application before carrying out meat vacuum packaging operation.  相似文献   
55.
Reinforced construction and strengthened building codes have been demonstrated to reduce expected damage from hurricanes in a cost effective manner. We examine whether reinforced construction (e.g. anchor bolts, hurricane clips, directional nailing) can provide efficient mitigation of property damage from tornadoes, using a case study of homes damaged in the May 3 1999 Oklahoma City Tornado. We find that if a package of wind resistant construction measures that cost no more than $500 could reduce insured losses by 30%, wind resistant construction could have a positive net present value in the most tornado prone states. A 30% reduction in wind damage is in line with estimates of damage reduction for construction in hurricane winds. The expected property damage reduction falls off rapidly in less tornado prone states.  相似文献   
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The impact of education on health care outcome has been studied in the past, but its role in the dialysis population is unclear. In this report, we evaluated this association. We used the United States Renal Data System data of end-stage renal disease patients aged 18 years. Education level at the time of end-stage renal disease onset was the primary variable of interest. The outcome of the study was patient mortality. We used four categories of education level: 0 = less than 12 years of education; 1 = high school graduate; 2 = some college; 3 = college graduate. Subgroups based on age, race, sex, donor type, and diabetic status were also analyzed. After adjustments for covariates in the Cox model, using individuals with less than 12 years of education as a reference, patients with college education showed decreased mortality with hazard ratio of 0.81 (95% confidence interval 0.69–0.95), P = 0.010. In conclusion, we showed that higher education level is associated with improved survival of patients on dialysis.  相似文献   
57.
In this article, the microporous membrane of stretched polytetrafluoroethylene (S-PTFE) film was modified through grafting hydrophilic methacrylic acid (MAA). SEM image showed that the grafted poly(methacrylic acid) (PMAA) covered uniquely on regular nanofiber-frame in S-PTFE. The surface contact angle of the membrane minishes rapidly with the increase of grafting ratio and falls down to the minimum point at 57° when the grafting ratio is about 4.7%. The water flux of the PTFE-g-PMAA membrane is very sensitive to pH values. At lower pH, the larger water flux was obtained. This contribution indicate the possibility of adjustable water flux by pH.  相似文献   
58.
An arteriovenous fistula (AVF) is the preferential hemodialysis (HD) access. The goal of this study was to identify factors associated with pre‐dialysis AVF failure in an elderly HD population. We used United States Renal Data System + Medicare claims data to identify patients ≥67 years old who had an AVF as their initial vascular access placed pre‐dialysis. Failure of the AVF to be used for initial HD, was used as the outcome. Logistic regression model was used to identify factors associated with AVF failure. The study cohort consisted of 20,360 subjects (76.2 ± 6.02 year old, 58.5% men). Forty‐eight percent of patients initiated dialysis using an AVF, while 52% used a catheter or an AVG. The following variables found to be associated with AVF failure when an AVF was created at least 4 months pre‐HD initiation: older age (odds ratio [OR] 1.01; 95% confidence interval [CI] 1.00–1.02), female gender (OR 1.69; 95% CI 1.55–1.83), black race (OR 1.41; 95% CI 1.26–1.58), history of diabetes (OR 1.22; 95% CI 1.06–1.39), cardiac failure (OR 1.26; 95% CI 1.15–1.37), and shorter duration of pre–end‐stage renal disease (ESRD) nephrology care (OR for a nephrology care of less than 6 months prior to ESRD of 1.22 compared with a pre‐ESRD nephrology follow up of more than 12 months; 95% CI 1.07–1.38). OR for AVF failure for the entire cohort showed similar findings. In an elderly HD population, there is an association of older age, female gender, black race, diabetes, cardiac failure and shorter pre‐ESRD nephrology care with predialysis AVF failure.  相似文献   
59.
The feasibility of nanofiltration membranes fabricated by static polyelectrolyte layer‐by‐layer deposition of poly(styrene sulfonate) and poly(allylamine hydrochloride) on poly(ether sulfone) ultrafiltration and alumina microfiltration membranes for the recovery of ionic liquid from low molecular weight sugar was investigated. The surface properties of these modified membranes were correlated with their performances. The selectivity for 1‐butyl‐3‐methylimidazolium chloride over cellobiose and glucose was found to be as high as 50.5/2.3 for modified alumina and 32.3/3.5 for modified poly(ether sulfone) membranes with optimized number of bilayers. The values for membrane permeance were 4.8 and 2.5 L m?1 h2 bar?1, respectively. For low depositions, the separation mechanism was predominantly governed by size‐exclusion. For higher depositions, the enhanced negative zeta potential of the modified membranes suggested preferred dominating electrostatic interactions, resulting in high selectivity of ionic liquids over low molecular weight sugars. At very high depositions, the molecular weight cut‐off of the membrane becomes constricting for size‐exclusion effect. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017 , 134 , 45349.  相似文献   
60.
Experimental data of reaction kinetics are usually in the form of concentration versus time. For kinetics investigation it is more convenient to have the data in the form of reaction rate versus concentration. Converting time-concentration data into concentration-reaction rate data is an ill-posed problem in the sense that if inappropriate methods are used the noise in the original data will be amplified leading to unreliable results. This paper describes a conversion procedure, independent of reaction rate model or mechanism, that manages to keep noise amplification under control. The performance of this procedure is demonstrated by applying it to several sets of published kinetic data. Since these data are accompanied by their rate equations, the computed rates are used to obtain the unknown parameters in these equations. Comparison of these parameters with published figures and the ease with which they are obtained highlights the advantages of the new procedure.  相似文献   
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