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41.
Axial concentration profiles of O2, CO2 and SO2 have been measured at different radial positions in a coal-fired fluidized bed combustor. The profiles show some spatial inhomogeneity in the bed, the degree of which depends on fluidizing velocity and amount of excess air. Comparison of SO2- with CO2-concentration profiles reveals that SO2 is formed in proportion to CO2 only with anthracite as fuel. With bituminous coals, SO2 is preferentially formed near the coal feed point. These results are discussed with regard to characteristic times of mixing and chemical reaction in fluidized beds, and SO2-formation characteristics of the employed coals obtained in a thermobalance. 相似文献
42.
The arc furnace technology is an ideally suited process for the treatment of hazardous and problematic waste. The operation conditions of the arc furnace can be adapted for optimal transformation of the waste material input into raw materials and usable products. The process can significantly reduce the impact of contaminated wastes and industrial residues, and enable material conversion and separation. Thus, the products of the process have various applications.
The capability of the process is illustrated with three examples, the treatment of bottom ash and filter ash from waste incineration plants, of stainless steel slags and of chromium containing residues from the refractory industry. 相似文献
43.
Nicola A. Irvine Bente Ruyter Tone-Kari Østbye Anna K. Sonesson Karen A. Lillycrop Gerd Berge Graham C. Burdge 《Lipids》2019,54(11-12):725-739
Adequate dietary supply of eicosapentaenoic acid (20:5n-3) and docosahexaenoic acid (22:6n-3) is required to maintain health and growth of Atlantic salmon (Salmo salar). However, salmon can also convert α-linolenic acid (18:3n-3) into eicosapentaenoic acid (20:5n-3) and docosahexaenoic acid (22:6n-3) by sequential desaturation and elongation reactions, which can be modified by 20:5n-3 and 22:6n-3 intake. In mammals, dietary 20:5n-3 + 22:6n-3 intake can modify Fads2 expression (Δ6 desaturase) via altered DNA methylation of its promoter. Decreasing dietary fish oil (FO) has been shown to increase Δ5fad expression in salmon liver. However, it is not known whether this is associated with changes in the DNA methylation of genes involved in polyunsaturated fatty acid synthesis. To address this, we investigated whether changing the proportions of dietary FO and vegetable oil altered the DNA methylation of Δ6fad_b, Δ5fad, Elovl2, and Elovl5_b promoters in liver and muscle from Atlantic salmon and whether any changes were associated with mRNA expression. Higher dietary FO content increased the proportions of 20:5n-3 and 22:6n-3 and decreased Δ6fad_b mRNA expression in liver, but there was no effect on Δ5fad, Elovl2, and Elovl5_b expression. There were significant differences between liver and skeletal muscle in the methylation of individual CpG loci in all four genes studied. Methylation of individual Δ6fad_b CpG loci was negatively related to its expression and to proportions of 20:5n-3 and 22:6n-3 in the liver. These findings suggest variations in dietary FO can induce gene-, CpG locus-, and tissue-related changes in DNA methylation in salmon. 相似文献
44.
This study examined the effects of feeding pasture vs. concentrate on the distribution of CLA isomers in the lipids of longissimus and semitendinosus muscle, liver and heart muscle, and subcutaneous fat in beef bulls. Sixty-four German Holstein and German Simmental bulls
were randomly allocated to either an indoor concentrate system or periods of pasture feeding followed by a finishing period
on a concentrate containing linseed to enhance their beef content of n−3 PUFA and CLA. The concentrations of CLA isomers in
the different tissues were determined by GC and silver ion HPLC. The diet affected the distribution of individual CLA isomers
in the lipids of the different tissues. The concentration (mg/100 g fresh tissue) of the most prominent isomer, cis-9,trans-11 18∶2, was increased up to 1.5 times in liver and heart tissue of bulls fed on pasture as compared with concentrate. However,
no diet effect was observed for cis-9,trans-11 18∶2 in the lipids of longissimus muscle and subcutaneous fat. In all tissues, the second-most abundant CLA isomer in concentratefed bulls was trans-7,cis-9 18∶2. In contrast, trans-11,cis-13 18∶2 was the second-most abundant CLA isomer in all investigated tissue lipids of pasture-fed bulls. The concentration
of the trans-11,cis-13 18∶2 isomer was up to 15 times higher in tissues of pasture-fed bulls as compared with concentrate-fed animals. Furthermone,
diet affected the concentrations of the CLA trans,trans 18∶2 isomers. Pasture feeding significantly increased the concentrations of some trans,trans 18∶2 isomers as compared with concentrate, predominantly trans-12,trans-14 18∶2 and trans-11,trans-13 18∶2. Overall, pasture feeding resulted in significantly increased concentrations of the sum of CLA isomers in the lipids
of longissimus, muscle, subcutaneous fat, heart and liver muscle of German Holstein and German Simmental bulls, but not in semitendinosus muscle. 相似文献
45.
Galesic Mirta; Garcia-Retamero Rocio; Gigerenzer Gerd 《Canadian Metallurgical Quarterly》2009,28(2):210
Objective: Icon arrays have been suggested as a potentially promising format for communicating risks to patients—especially those with low numeracy skills—but experimental studies are lacking. This study investigates whether icon arrays increase accuracy of understanding medical risks, and whether they affect perceived seriousness of risks and helpfulness of treatments. Design: Two experiments were conducted on samples of older adults (n = 59, 62 to 77 years of age) and university students (n = 112, 26 to 35 years of age). Main Outcome Measures: Accuracy of understanding risk reduction; perceived seriousness of risks; perceived helpfulness of treatments. Results: Icon arrays increased accuracy of both low- and high-numeracy people, even when transparent numerical representations were used. Risks presented via icon arrays were perceived as less serious than those presented numerically. With larger icon arrays (1,000 instead of 100 icons) risks were perceived more serious, and risk reduction larger. Conclusions: Icon arrays are a promising way of communicating medical risks to a wide range of patient groups, including older adults with lower numeracy skills. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
46.
Gerd K. Rosenkranz 《Computational statistics & data analysis》2009,53(3):812-819
Abnormal laboratory data from clinical trials are considered precursors of potential organ dysfunction. Routine analysis of these data focusses primarily on the incidence of extremely high or low values relative to normal ranges, or the change of these incidences compared to baseline. Alternatively, the worst values from each individual patient are analyzed. Where feasible, graphical representations of the time course of lab measurements are displayed, often for each subject individually. However, only rarely is an attempt made to model the dynamics of the measurements over time. Stochastic processes can be used to model laboratory measurements and specifically Ornstein-Uhlenbeck processes have some properties that are suitable for this purpose. Models based on these processes can account for potential systematic effects relevant for all or a group of subjects as well as the random variation between subjects. The idea is to estimate parameters of these processes in order to quantify effects of drugs or other medical treatments. Results based on simulations and real data will be presented. 相似文献
47.
48.
Christophe Rapine Nadia Brauner Gerd Finke Vassilissa Lebacque 《Journal of Scheduling》2012,15(2):127-139
For an industrial application in the chemical industry, we were confronted with the planning of experiments, where human intervention
of a chemist is required to handle the starting and termination of each of the experiments. This gives rise to a new type
of scheduling problem, namely problems of finding schedules with time periods when the tasks can neither start nor finish.
We consider in this paper the natural case of small periods where the duration of the periods is smaller than any processing time. This assumption corresponds to our chemical
experiments lasting several days, whereas the operator unavailability periods are typically single days or week-ends. These
problems are analyzed on a single machine with the makespan as criterion. 相似文献
49.
Diana Brumini Camilla Bø Furlund Irene Comi Tove Gulbrandsen Devold Donata Marletta Gerd E. Vegarud Christine Monceyron Jonassen 《International Dairy Journal》2013,28(2):109-111
Antiviral activity of Ragusano donkeys' milk proteins was investigated for the effect on echovirus type 5, known to infect the gastrointestinal tract of humans. Three protein fractions were tested; casein (CN), whey protein (WP) and a low molecular whey protein fraction (LWP; <30,000 Da). The antiviral activity of WP and LWP was tested on echovirus type 5 at three concentrations (1, 5 and 10 mg mL?1); CN was assessed only at the lower concentration. All donkey milk protein fractions showed significant inhibition on virus replication at the concentration of 1 mg mL?1, and both WP and LWP fractions showed significant inhibition on the virus replication at all concentrations tested. The strongest antiviral effect was observed for the WP fraction. These findings show that the different whey proteins in donkey milk, probably acting in synergy, exert antiviral activity on echovirus 5 and might contribute to prevent gastrointestinal virus infections in humans. 相似文献
50.
Quirin Meyer Jochen Süßmuth Gerd Sußner Marc Stamminger Günther Greiner 《Computer Graphics Forum》2010,29(4):1405-1409
In this paper we analyze normal vector representations. We derive the error of the most widely used representation, namely 3D floating‐point normal vectors. Based on this analysis, we show that, in theory, the discretization error inherent to single precision floating‐point normals can be achieved by 250.2 uniformly distributed normals, addressable by 51 bits. We review common sphere parameterizations and show that octahedron normal vectors perform best: they are fast and stable to compute, have a controllable error, and require only 1 bit more than the theoretical optimal discretization with the same error. 相似文献