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排序方式: 共有2198条查询结果,搜索用时 15 毫秒
41.
Dr. Christoph Goebel Prof.?Dr. Hans-Arno Jacobsen Victor del Razo Mag.? Christoph Doblander Dipl.-Ing. Jose Rivera Dipl-Inform.?Wirt Jens Ilg Dr. Christoph Flath Prof.?Dr. Hartmut Schmeck Prof.?Dr. Christof Weinhardt Dipl-Inform. Daniel Pathmaperuma Prof.?Dr. Dr.?h.?c. Hans-Jürgen Appelrath Prof.?Dr. Michael Sonnenschein Prof.?Dr. Sebastian Lehnhoff Prof.?Dr. Oliver Kramer Prof.?Dr. Thorsten Staake Prof.?Dr. Elgar Fleisch Prof.?Dr. Dirk Neumann Prof.?Dr. Jens Strüker Dr. Koray Erek Prof.?Dr. Rüdiger Zarnekow Dr. Holger Ziekow Prof.?Dr. J?rg L?ssig 《WIRTSCHAFTSINFORMATIK》2014,56(1):31-39
Due to the increasing importance of producing and consuming energy more sustainably, Energy Informatics (EI) has evolved into a thriving research area within the CS/IS community. The article attempts to characterize this young and highly dynamic field of research by describing current EI research topics and methods and provides an outlook of how the field might evolve in the future. It is shown that two general research questions have received the most attention so far and are likely to dominate the EI research agenda in the coming years: How to leverage information and communication technology (ICT) to (1) improve energy efficiency, and (2) to integrate decentralized renewable energy sources into the power grid. Selected EI streams are reviewed, highlighting how the respective research questions are broken down into specific research projects and how EI researchers have made contributions based on their individual academic background. 相似文献
42.
Michael J. Banach Stephen J. Clarson Gregory Beaucage Jason Benkoski Tom Mates Edward J. Kramer Richard A. Vaia 《应用聚合物科学杂志》2002,86(8):2021-2024
For many microelectronic and optoelectronic applications, polymer thin films require the addition of small molecules. However, the thin‐film geometry and associated processing techniques will influence the final morphology and compositional distribution of the constituents. It is therefore important that these be examined directly rather than inferred from bulk measurements. As an example system, the concentration and distribution of Disperse Red 1 (DR1) molecules in poly(methyl methacrylate) thin films were examined. Ultraviolet visibility spectroscopy and dynamic secondary ion mass spectrometry indicate that the composition of the molecules decreased dramatically with thermal treatment of the film. The sublimation of the chromophore was observed to occur at temperatures well below the melting point of the small molecule and the glass transition of the pure polymer; this solute loss manifested itself in changes in the glass transition temperature of the film. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 86: 2021–2024, 2002 相似文献
43.
Avi Parush Chelsea Kramer Tara Foster-Hunt Alicia McMullan Kathryn Momtahan 《Cognition, Technology & Work》2014,16(1):47-57
Teamwork is prevalent in many work contexts. This study explored the similarities and differences in teamwork processes across different healthcare work contexts with the aim of assessing knowledge transfer feasibility. The research approach was to aggregate team communication analyses from four healthcare contexts to uncover teamwork similarities and differences. The four healthcare contexts included two handoffs and two surgery contexts. The communication analysis segmented communication into meaningful sequences. It categorized utterances into content categories and verbal behaviors. There were a few similar content categories across the four contexts. A clear information structure emerged in the two handoff contexts. In addition, there were more dialogues and requests in the surgeries compared to more reports in the handoffs. The content similarities suggest that some knowledge is transferable among the contexts. However, the differences in communication patterns reflect fundamental differences between handoff and surgery contexts in some teamwork processes. This research demonstrated that using communication analysis can uncover similarities and differences in team cognition and teamwork processes across work contexts. This in turn can help determine what knowledge and methods pertaining to team training, procedures, and technology are transferable across the contexts. 相似文献
44.
The action of the tumor promoter, phorbol 12,13-dibutyrate (PDBu), on rabbit peritoneal and human neutrophils is associated
with stimulation of14C-arachidonic acid incorporation into phospholipids within 1–2 min. Stimulated14C-arachidonate incorporation was relatively selective for phosphatidylinositol (PI) in rabbit neutrophils. In contrast, the
secretory response of human neutrophils to PDBu coincided with stimulated label incorporation into phosphatidylserine (PS),
phosphatidylcholine (PC), phosphatidylethanolamine (PE), phosphatidic acid (PA) and PI. Significant increases in label incorporation
were observed with PDBu concentrations as low as 2 nM, and the dose response of stimulated label incorporation paralleled
that of evoked lysozyme secretion. A parallel, but partial, inhibition of PDBu-stimulated PI labeling and enzyme release was
observed after exposing rabbit neutrophils to calcium-deprived medium, whereas calcium deprivation failed to significantly
depress either of these stimulant actions of PDBu in human neutrophils. Further, in rabbit neutrophils PDBu elicited an increase
in cell associated45Ca. However, PDBu was unable to promote the incorporation of32P orthophosphate into PI or enhance phospholipase A2 activity in broken cells. These findings suggest that one expression of the interaction between phorbol esters and their
receptors on neutrophils involves the turnover of arachidonic acid in phospholipids. This stimulated turnover of arachidonate
may be a critical step in the cascade of events associated with neutrophil activation. 相似文献
45.
Three hundred (experiment I) and 350 (experiment II) weanling, 3-week-old male Sprague-Dawley rats weighing between 40–50
g were randomly assigned two per cage and 50 per dietary treatment to study the effect of dietary fatty acid balance on myocardial
lesions. The following oils were tested: Experiment I.Brassica napus var. Tower rapeseed oil [Tower RSO, 1974 cultivar and 1975 cultivar, each containing 0.3% erucic (22∶1) acid];B. napus var. Zephyr RSO containing 0.9% 22∶1; corn oil; olive oil; and soybean oil. Experiment II.B. napus var. Tower RSO (1974 cultivar), olive oil, soybean oil, and the following oils to which was added the indicated level of
free 22∶1; Tower +0.5% 22∶1; Tower +5.6% 22∶1; olive oil +4.4% 22∶1; soybean oil +5.7% 22∶1. In each case the oils were incorporated
in a semisynthetic diet at a level of 20% by weight. Heart and heart lipid weights of rats fed the different oils did not
differ statistically from each other. Fatty acid analyses of heart lipids revealed that the fatty acid composition of the
cardiac lipids reflected that of the diet fed. In experiment I, there was a definite but significantly lower incidence (P<0.01)
and severity (P<0.01) of heart lesions in rats fed control oils (corn, olive, soybean) than in rats fed rapeseed oils. Also,
in experiment II, a definite but lower incidence and severity of heart lesions occurred in rats fed control oils (soybean,
olive) compared to rats fed Tower RSO or this oil with added free 22∶1. Adding 22∶1 to an oil naturally high in 18∶3 (soybean)
did not alter the incidence of heart lesions, whereas adding 22∶1 to an oil naturally high in 18∶1 (olive) increased significantly
(P<0.01) both the incidence and severity of heart lesions. Thus, it appears that the background incidence of heart lesions
that are found in the rat in any case, and which are increased by rapeseed oil feeding, is caused by the imbalanced fatty
acid composition of the oil for the growing rat, i.e. high monoenes (18∶1, 20∶1, and 22∶1) and high 18∶3 and is not only due
to the presence of excess 18∶3.
Contribution No. 706, Animal Research Institute. 相似文献
46.
Linear 1,2-polybutadiene, glass transition temperature (Tg) ?18°C, is crosslinked at ?10°C, to ?20°C by γ irradiation while strained in simple extension, with extension, ratios (λ0) from 1.2 to 2.7. After release, the sample retracts to a state of ease (λs) at room temperature. From equilibrium stress–strain measurements up to a stretch ratio relative to the state of ease (Λ) of 1.2, together with λ0 and λs, the concentration of network strands terminated by trapped entanglements (νN) is calculated. For this purpose, a three-constant Mooney–Rivlin formulation is used, in which the entanglement network is described by Mooney–Rivlin coefficients C1N and C2N, whereas the crosslink networks is described by the coefficient C1x only. The ratio ψN = C2N/(C1N + C2N) is estimated from parallel studies of nonlinear stress relaxation of the uncrosslinked polymer, taking into account the thermal history before and during irradiation. For substantial degrees of crosslinking, i.e., for R0′ = νx/νN > 0.4 (where νN is the concentration of network strands terminated by crosslinks), and for λ0 < 1.8, C2N agrees rather well with the value obtained from stress relaxation of the uncrosslinked polymer in the range of time scale where it is nearly independent of time (1.87 X 105 pascals). The corresponding value of νN is 2.3 × 10?4 moles/cm3, in good agreement with that obtained from viscoelastic measurements of the uncrosslinked polymer in the plateau zone (2.5 × 10?4). However, for R0′ ? 0.2, smaller values of C2N and νN are obtained, indicating that for low degrees of crosslinking the entanglements are not completely trapped. Also, for higher values of λ0, C2N and νN turn out to be somewhat smaller. Similar, less extensive results were obtained previously on a 1,2-polybutadiene with somewhat higher vinyl content and a higher Tg. Crosslinked samples of both these polymers were subjected to equilibrium stress–strain measurements in simple elongation from the state of ease at higher strains up to Λ = 1.7. The results agreed closely with calculations from the three-constant Mooney–Rivlin theory. 相似文献
47.
Procedures for the large scale isolation of pure triglycerides and fractions rich in nontriglyceride components from Span
rapeseed oil are described. Fractionation ofBrassica campestris var. Span rapeseed oil by molecular distillation yielded 4 triglyceride fractions, all of which contained traces of sterol
esters. An additional triglyceride fraction rich in free and esterified sterols and other volatile components was obtained
from the oil. Separation by adsorption chromatography of Span rapeseed oil yielded three fractions: A) a pure triglyceride
fraction; B) a triglyceride fraction rich in sterol esters; and C) another fraction containing free sterols and other polar
components.
Contribution no. 559 Animal Research Institute. 相似文献
48.
Isothermal differential thermal analysis (DTA) is well known for measuring thermal stability of polyolefins by determining the oxidative induction time at elevated temperatures. Oxidative induction time, measured up to 7,000 hours and over a temperature range from 240°C to 120°C, has been used to study the stability of polybutene-1 and crosslinked polyethylene in the melt state. The Arrhenius plots of DTA results show that straight line extrapolation from high to low temperatures is not possible. Thermoanalytically measured oxidation induction times and mechanical failure in oven aging experiments agree for polybutene and crosslinked polyethylene, Measurements of molecular weight and of mechanical properties of polybutene-1 during the induction period of oven aging experiments at low temperatures revealed that molecular weight and tensile properties are not sensitive indicators for the beginning of aging. The state of deterioration can be estimated easier by measurement of residual lifetime in the isothermal DTA experiment. Diffusion processes of stabilizers in polyolefins, as well as the consumption of stabilizer at elevated temperatures, especially during the induction period also was observed by DTA. Finally the extraction of stabilizer by hot water was measured by isothermal DTA. 相似文献
49.
Male, female and castrated rats, three wk of age, were fed a low-fat diet for 14 wk followed by high-fat diets (20% by weight)
for one wk containing graded levels of erucic acid from 1 to 50%, to evaluate the effect of short-term feeding and interaction
of male sex hormones on formation of heart lesions. Some rats within each group were returned to the low-fat diet for one
wk after the test period. For comparison, one group of three-wk-old male rats was fed the high fat 50% erucic acid diet for
15 wk. Erucic acid depressed growth rate and food consumption and increased cardiac lipidosis and triglycerides proportional
to the erucic acid content of the diet. There were no sex differences, and the effects disappeared once rats were returned
to the low-fat diet for one week. There was a significance (P<0.05) in the incidence of myocardial necrosis among male rats
fed increased levels of erucic acid for one week, but the response was not linear to the increase in dietary erucic acid.
Furthermore, the response was much less than in males fed the 50% erucic acid diet continually for 15 weeks. These results
suggest that the short-term model is not a suitable substitute for the long-term feeding trial to test the cardiopathogenicity
of a vegetable oil. The significantly lower incidence in myocardial lesions in female and castrated male rats compared with
male rats suggests involvement of sex hormones. However, the process appears to be long term, since changes in cardiac lipids
and their fatty acid pattern between sexes became evident after one wk on diet but was significant only after long-term feeding.
Deceased. 相似文献
50.
The precision and accuracy of the Iatroscan method was evaluated by comparing the results obtained with established phosphorus
and gas chromatographic techniques. A complete lipid class analysis of rat heart lipids was chosen in order to evaluate the
performance of the Iatroscan method for biological samples which contained both neutral lipids and phospholipids. A partial
scan and repeat development with chloroform/methanol/water (68.5∶29∶2.5) was introduced to achieve consistently good separations
of the phospholipids on the Chromarods in the Iatroscan method. The results showed that the precision of the Iatroscan method
for some lipid classes was comparable to that of phosphorus or gas chromatographic techniques, while for other lipid classes
it was lower. Compared to the data obtained using the phosphorus method, the Iatroscan data were generally similar, while
the gas chromatographic method generally gave lower values. These findings, together with the advantages of time required
for analysis, size of sample, and universality of detection, suggest that the Iatroscan is a valuable complementary method
for complex lipid analyses. 相似文献