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81.
The pilot feed mill at Kansas State University was heated to temperatures of 50°C for 28–35 h during August 4–6, 1999 using natural gas heaters to kill stored-product insects. A three-parameter nonlinear regression model satisfactorily described temperature profiles on each of the four mill floors and was useful in showing differences among floors in the number of hours taken to reach 50°C and hours above 50°C. Pitfall traps with food and pheromone lures and sticky traps with pheromone lures were used to sample adults of beetles and moths, respectively, between July 8 and December 1, 1999 to evaluate heat treatment effectiveness. A total of 32 insect species representing 26 families in seven orders were captured in traps. Immediately after heat treatment, there was 95% reduction in total beetle captures in pitfall traps and 99% reduction in moth captures in sticky traps. Trap captures of the almond moth, Cadra cautella (Walker) and cigarette beetle, Lasioderma serricorne (L.) were significantly reduced and remained low after heat treatment. However, trap captures of the flat grain beetle, Cryptolestes pusillus (Schöenherr), Indianmeal moth, Plodia interpunctella (Hübner), and red flour beetle, Tribolium castaneum (Herbst) increased gradually after heat treatment, especially on the 1st and 4th floors. Our results indicated that traps are valuable tools for gauging the degree and duration of insect suppression obtained by heat treatment. In addition to trapping, visual inspection of the mill areas and absolute sampling of ingredients, products and spillage should be undertaken, so that areas of incipient insect reinfestation can be identified and potential problems rectified or averted.  相似文献   
82.
Examined how therapists and clients construct, express, and apprehend metaphors. Five client-generated and 6 therapist-generated metaphors were selected across 4 therapy dyads, with 1 therapy session being focused on in each dyad. The clients had been in therapy for 12 sessions, and the therapists had 5–20 yrs of experience. Each S's and therapist's recollections of the metaphoric events were stimulated by audiotape playback within 24 hrs of the therapy session. Participants' recollections included thoughts and feelings that had been kept private in the therapy session. A qualitative analysis of the participants' accounts revealed that each dyad entailed 1 of 2 distinct patterns of metaphoric communication. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
83.
Almost all of the bitter substances which are lost during pilot-scale brewery fermentations using yeast N.C.Y.C. 240 can be recovered unchanged. The largest losses of bitter substances are associated with the dirty head formed during the first 18 hours of a fermentation. Hop utilization can be improved by folding this dirty head back into the fermenting wort. This process is most effective when carried out after the ethanol concentration of the wort has reached about 1%, but before the bitter substances have had the opportunity to undergo extensive oxidative degradation. Losses of bitter substances are lower when 25% of a malt grist is replaced by wheat flour. There is no consistent relationship between losses of bitter substances and either the assimilable or total nitrogen of wort. With increase in wort O.G. there is increasing loss of bitter substances, such losses being principally associated with the dirty head.  相似文献   
84.
A practical bioassay for the acid-ethanol soluble non-suppressible insulin-like activity (NSILA-S) of individual serum samples has been developed utilizing the incorporation of 14C-glucose into the lipid faction of isolated adipocytes. NSILA-S activity was correlated with somatotropin status. Thus, the mean potencies (+/-SD) relative to an extract of pooled normal human serum were: normal samples 1.11 +/- 0.14, acromegalic 2.91 +/- 0.72, and somatotropin deficient 0.13 +/- 0.06. This variation in NSILA-S was not due to variability in extraction recoveries. The within assay precision was 9% (coefficient of variation) and the between assay 23%. This method allows the simultaneous extraction and processing of relatively large numbers of samples, and compares favorably with other more complex methods. Because of the evidence that NSILA-S may be related to the somatomedins, the present method should provide a simpler and more reliable alternative to the cartilage bioassays used to measure somatomedin activity.  相似文献   
85.
Experiments are described in which the boiling of wort is replaced by a hold at 85° C, and the effects upon beer quality are reported. Beers with normal shelf-life and sound flavour can be produced without the wort having been boiled.  相似文献   
86.
To examine release of insulin from tissues of the exercising llin, growth hormone, cortisol, and circulating metabolites were studied in five men before, during, and after exercise on a bicycle ergometer at 60% of their maximum work capacity. At rest, insulin, growth hormone, and cortisol were taken up by leg tissues. During exercise arterial plasma insulin concentration fell, but cortisol and growth hormone levels rose; there was net release of insulin into venous blood but little change in uptake of cortisol and growth hormone. Insulin release persisted after exercise for 15-30 min. During exercise arterial concentrations and uptake of glucose and free fatty acids (FFA) increased. Examination of the changes in hormones and metabolites failed to identify any single hormonal or metabolic factor causing the observed reversal of insulin uptake with exercise.  相似文献   
87.
Investigated the interactive nature of clients' and therapists' experiencing during the expression, apprehension, and elaboration of metaphors. Analysis of audiotaped inquiry interviews between 4 clients (in therapy for at least 12 sessions) and 4 therapists (1 psychoanalyst, 1 Gestalt therapist, and 2 eclectics within a person-centered and psychodynamic framework) was conducted. Metaphors emerged from the associated meaning context when participants attempted to verbally depict felt experiences during therapy sessions. Metaphors symbolized inner experience by (1) providing an associative link to the experience, (2) representing aspects of self-identity, and (3) symbolizing role relationship patterns. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
88.
High-fat diet (HFD)-induced comorbid cognitive and behavioural impairments are thought to be the result of persistent low-grade neuroinflammation. Metformin, a first-line medication for the treatment of type-2 diabetes, seems to ameliorate these comorbidities, but the underlying mechanism(s) are not clear. Pituitary adenylate cyclase-activating peptide (PACAP) and vasoactive intestinal peptide (VIP) are neuroprotective peptides endowed with anti-inflammatory properties. Alterations to the PACAP/VIP system could be pivotal during the development of HFD-induced neuroinflammation. To unveil the pathogenic mechanisms underlying HFD-induced neuroinflammation and assess metformin’s therapeutic activities, (1) we determined if HFD-induced proinflammatory activity was present in vulnerable brain regions associated with the development of comorbid behaviors, (2) investigated if the PACAP/VIP system is altered by HFD, and (3) assessed if metformin rescues such diet-induced neurochemical alterations. C57BL/6J male mice were divided into two groups to receive either standard chow (SC) or HFD for 16 weeks. A further HFD group received metformin (HFD + M) (300 mg/kg BW daily for 5 weeks) via oral gavage. Body weight, fasting glucose, and insulin levels were measured. After 16 weeks, the proinflammatory profile, glial activation markers, and changes within the PI3K/AKT intracellular pathway and the PACAP/VIP system were evaluated by real-time qPCR and/or Western blot in the hypothalamus, hippocampus, prefrontal cortex, and amygdala. Our data showed that HFD causes widespread low-grade neuroinflammation and gliosis, with regional-specific differences across brain regions. HFD also diminished phospho-AKT(Ser473) expression and caused significant disruptions to the PACAP/VIP system. Treatment with metformin attenuated these neuroinflammatory signatures and reversed PI3K/AKT and PACAP/VIP alterations caused by HFD. Altogether, our findings demonstrate that metformin treatment rescues HFD-induced neuroinflammation in vulnerable brain regions, most likely by a mechanism involving the reinstatement of PACAP/VIP system homeostasis. Data also suggests that the PI3K/AKT pathway, at least in part, mediates some of metformin’s beneficial effects.  相似文献   
89.
The development of a fully three-dimensional finite volume morphodynamic model, for simulating fluid and sediment transport in curved open channels with rigid walls, is described. For flow field simulation, the Reynolds-averaged Navier–Stokes equations are solved numerically, without reliance on the assumption of hydrostatic pressure distribution, in a curvilinear nonorthogonal coordinate system. Turbulence closure is provided by either a low-Reynolds number k?ω turbulence model or the standard k?ε turbulence model, both of which apply a Boussinesq eddy viscosity. The sediment concentration distribution is obtained using the convection-diffusion equation and the sediment continuity equation is applied to calculate channel bed evolution, based on consideration of both bed load and suspended sediment load. The governing equations are solved in a collocated grid system. Experimental data obtained from a laboratory study of flow in an S-shaped channel are utilized to check the accuracy of the model’s hydrodynamic computations. Also, data from a different laboratory study, of equilibrium bed morphology associated with flow through 90° and 135° channel bends, are used to validate the model’s simulated bed evolution. The numerically-modeled fluid and sediment transportation show generally good agreement with the measured data. The calculated results with both turbulence models show that the low-Reynolds k?ω model better predicts flow and sediment transport through channel bends than the standard k?ε model.  相似文献   
90.
A numerical study of a double-pipe helical heat exchanger was performed to ascertain the residence time, temperature, and processing uniformity for food processing applications. A range of laminar flow rates were used, with both parallel flow and counterflow configurations. Both heating and cooling in the inner tube were studied. Heating/cooling uniformity was estimated by using a first-order kinetics model for sterilization. Process uniformity is important in the quest for high quality product and this report is a first study for the uniformity in double-pipe helical heat exchangers.  相似文献   
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