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Software and Systems Modeling - Our everyday lives are increasingly pervaded by digital assistants and smart devices forming the Internet of Things (IoT). While user interfaces to directly monitor...  相似文献   
93.
Differences in fat metabolism are of importance in relation to energy balance. Low fat‐oxidizers (LFO) are thought to be more prone for developing obesity. We studied whether LFO have different fasting adipose tissue (AT) protein profiles than high fat‐oxidizers (HFO). Six LFO and six HFO subjects were selected from an obese group (n = 99, body mass index>30 kg/m2) taking part in a multi‐center study (Nutrient‐Gene interaction in human obesity) based on the postprandial fat oxidation capacity after a high fat load. AT protein profiles were studied by 2‐DE. Differential proteins were clustered with MAPPfinder according to their function. Protein profiles of purified blood cells and adipocytes served to confine the comparison to adipocyte‐specific proteins in AT profiles of LFO and HFO subjects. LFO had increased mitochondrial ROS scavengers possibly related to long‐chain unsaturated fatty acid‐induced increases in mitochondrial ROS‐production. Carbohydrate oxidation seemed to be reduced since expression of several proteins from the glycolysis pathway was lower in LFO. Up‐regulation of the valine catabolism at the level of methylmalonate‐semialdehyde dehydrogenase appeared to be (part of) the compensatory mechanism. In conclusion, the fasting AT protein profile of LFO and HFO differ at the level of ROS scavenging, the glycolysis pathway and valine metabolism.  相似文献   
94.
The flexural capacity of concrete beams can be efficiently and effectively improved through bonding fiber-reinforced plastic (FRP) plates to the tensile side. Failure of the strengthened member often occurs through debonding of the FRP from the concrete substrate. If the ultimate FRP strain at debonding failure is known, the moment capacity of the member can be obtained through a simple section analysis. In the American Concrete Institute (ACI) Design Guideline, simple empirical equations are proposed to find the ultimate FRP strain in terms of the FRP stiffness alone. However, when the proposed equations are compared to experimental data, a very large scatter is observed, indicating that the effect of other parameters cannot be neglected. In the present investigation, a new empirical approach to obtain the FRP debonding strain is developed. With a comprehensive experimental database of 143 tests, a neural network relating the ultimate FRP strain to various geometric and material parameters is trained and validated. Using the validated network, an empirical design curve and several correction equations are generated to provide a simple means to find the debonding strain in practical design. Through use of the chart and equations, the calculated ultimate failure moments for the 143 tests in our database are found to be in good agreement with experimental results. The applicability of the new empirical approach to the failure prediction of strengthened members is thus demonstrated.  相似文献   
95.
Dialysis hypotension occurs frequently and is associated with increased morbidity, mortality, and may influence quality of life. We investigated the influence of blood volume (BV)-controlled ultrafiltration on hemodynamic stability and quality of life in a prospective multiple crossover study. Nineteen patients were consecutively treated with standard hemodialysis (HD), BV-controlled ultrafiltration, and again with standard ultrafiltration during 3-week phases, during which different hemodynamic parameters, ultrafiltrate quantities, dry weight, and quality of life were measured. Blood volume-controlled ultrafiltration resulted in increased hemodynamic stability: systolic blood pressure was significantly higher after treatment with BV-controlled HD compared with both standard treatments (p=0.018 and 0.043, respectively). Also, systolic blood pressure reduction, as a measure of blood pressure stability, was significantly smaller during the BV-controlled phase (-3.9 mmHg) compared with both standard phases (-13.7 and -11.0 mmHg): p=0.003 and 0.035, respectively. No difference was found in the occurrence of large decreases of blood pressure (>30 mmHg), decreases below 90 mmHg systolic pressure, or subjective complaints during treatment or after treatment between both treatment modalities. During the course of the study, the dry weight decreased significantly from mean 73.3 to mean 70.9 kg, and the amount of ultrafiltrate was significantly larger using BV-controlled HD compared with standard treatment (mean 2407 vs. mean 2266 mL; p=0.035). Quality of life, measured by visual analog scales (VAS), showed discrete but no consistent differences between study phases. We conclude that BV-controlled HD increases hemodynamic stability and ultrafiltrate amount compared with a standard treatment. No consistent change in quality of life is found between both treatment modalities.  相似文献   
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Within the next few decades, the number of older drivers operating a vehicle will increase rapidly (Eurostat, 2011). As age increases so does physical vulnerability, age-related impairments, and the risk of being involved in a fatal crashes. Older drivers experience problems in driving situations that require divided attention and decision making under time pressure as reflected by their overrepresentation in at-fault crashes on intersections. Advanced Driver Assistance Systems (ADAS) especially designed to support older drivers crossing intersections might counteract these difficulties. In a longer-term driving simulator study, the effects of an intersection assistant on driving were evaluated. 18 older drivers (M = 71.44 years) returned repeatedly completing a ride either with or without a support system in a driving simulator. In order to test the intersection assistance, eight intersections were depicted for further analyses. Results show that ADAS affects driving. Equipped with ADAS, drivers allocated more attention to the road center rather than the left and right, crossed intersections in shorter time, engaged in higher speeds, and crossed more often with a critical time-to-collision (TTC) value. The implications of results are discussed in terms of behavioral adaptation and safety.  相似文献   
98.
Scope: High‐folic‐acid diets during pregnancy result in obesity in the offspring, associated with altered DNA‐methylation of hypothalamic food intake neurons. Like folic acid, the methyl‐donor choline modulates foetal brain development, but its long‐term programing effects on energy regulation remain undefined. This study aims to describe the effect of choline intake during pregnancy on offspring phenotype and hypothalamic energy‐regulatory mechanisms. Methods and results: Wistar rat dams are fed an AIN‐93G diet with recommended choline (RC, 1 g kg?1 diet), low choline (LC, 0.5‐fold), or high choline (HC, 2.5‐fold) during pregnancy. Male pups are terminated at birth and 17 weeks post‐weaning. Brain 1‐carbon metabolites, body weight, food intake, energy expenditure, plasma hormones, and protein expression of hypothalamic neuropeptides are measured. HC pups have higher expression of the orexigenic neuropeptide‐Y neurons at birth, consistent with higher cumulative food intake and body weight gain post‐weaning compared to RC and LC offspring. LC pups have lower leptin receptor expression at birth and lower energy expenditure and activity during adulthood. Conclusion: Choline content of diets that are consumed by rats during pregnancy affects the later‐life phenotype of offspring, associated with altered in utero programing of hypothalamic food intake regulation.  相似文献   
99.
The Linear-No-Threshold (LNT) model predicts a dose-dependent linear increase in cancer risk. This has been supported by biological and epidemiological studies at high-dose exposures. However, at low-doses (LDR ≤ 0.1 Gy), the effects are more elusive and demonstrate a deviation from linearity. In this study, the effects of LDR on the development and progression of mammary cancer in FVB/N-Tg(MMTVneu)202Mul/J mice were investigated. Animals were chronically exposed to total doses of 10, 100, and 2000 mGy via tritiated drinking water, and were assessed at 3.5, 6, and 8 months of age. Results indicated an increased proportion of NK cells in various organs of LDR exposed mice. LDR significantly influenced NK and T cell function and activation, despite diminishing cell proliferation. Notably, the expression of NKG2D receptor on NK cells was dramatically reduced at 3.5 months but was upregulated at later time-points, while the expression of NKG2D ligand followed the opposite trend, with an increase at 3.5 months and a decrease thereafter. No noticeable impact was observed on mammary cancer development, as measured by tumor load. Our results demonstrated that LDR significantly influenced the proportion, proliferation, activation, and function of immune cells. Importantly, to the best of our knowledge, this is the first report demonstrating that LDR modulates the cross-talk between the NKG2D receptor and its ligands.  相似文献   
100.
In this article, we report on the dye flocculation performance of polyampholytes containing hydrophobically modified cationic, hydrophilic nonionic, and anionic monomer units, always with an excess of cationic charges. The results are compared with homopolymers and with those obtained using nonstoichiometric polyelectrolyte–surfactant complex (PSC) dispersions with adjustable surface charge density. The polyampholytes as well as the PSC can successfully remove the dye Celliton Fast Blue (Dispers blue 3). The efficiency of dye separation is mainly influenced by the charge of polymers or complexes, demonstrating that charge neutralization is one flocculation mechanism. However, PSC, which are almost neutral, are also able to remove the dye due to their size and structure. In this case, the degree of dye removal is a little bit better and the so‐called flocculation window is broader as in the case of charge neutralization. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci 104: 1342–1349, 2007  相似文献   
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