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91.
This study investigated the impact of supplementing goats' milk with quinoa extracts, in the range of 5, 10 and 15 g/100 g on the milk fermentation. The properties of yoghurt produced from this milk, which include viscosity, microstructure and sensory acceptability, were assessed. The supplementation of goats' milk with quinoa extracts, particularly permeate extract, reduced the fermentation time and enhanced the viability of lactic acid bacteria. Supplementation of yoghurt with increased levels of quinoa extracts increased the apparent viscosity and changed the yoghurt protein matrix. Panellists highly accepted the yoghurt that contained quinoa permeate extract.  相似文献   
92.
The inositol 1,4,5-triphosphate receptor-associated 2 (IRAG2) is also known as Jaw1 or lymphoid-restricted membrane protein (LRMP) and shares homology with the inositol 1,4,5-triphosphate receptor-associated cGMP kinase substrate 1 (IRAG1). IRAG1 interacts with inositol trisphosphate receptors (IP3 receptors /IP3R) via its coiled-coil domain and modulates Ca2+ release from intracellular stores. Due to the homology of IRAG1 and IRAG2, especially in its coiled-coil domain, it is possible that IRAG2 has similar interaction partners like IRAG1 and that IRAG2 also modulates intracellular Ca2+ signaling. In our study, we localized IRAG2 in pancreatic acinar cells of the exocrine pancreas, and we investigated the interaction of IRAG2 with IP3 receptors and its impact on intracellular Ca2+ signaling and exocrine pancreatic function, like amylase secretion. We detected the interaction of IRAG2 with different subtypes of IP3R and altered Ca2+ release in pancreatic acinar cells from mice lacking IRAG2. IRAG2 deficiency decreased basal levels of intracellular Ca2+, suggesting that IRAG2 leads to activation of IP3R under unstimulated basal conditions. Moreover, we observed that loss of IRAG2 impacts the secretion of amylase. Our data, therefore, suggest that IRAG2 modulates intracellular Ca2+ signaling, which regulates exocrine pancreatic function.  相似文献   
93.
Distributed databases allow us to integrate data from different sources which have not previously been combined. In this article, we are concerned with the situation where the data sources are held in a distributed database. Integration of the data is then accomplished using the Dempster–Shafer representation of evidence. The weighted sum operator is developed and this operator is shown to provide an appropriate mechanism for the integration of such data. This representation is particularly suited to statistical samples which may include missing values and be held at different levels of aggregation. Missing values are incorporated into the representation to provide lower and upper probabilities for propositions of interest. The weighted sum operator facilitates combination of samples with different classification schemes. Such a capability is particularly useful for knowledge discovery when we are searching for rules within the concept hierarchy, defined in terms of probabilities or associations. By integrating information from different sources, we may thus be able to induce new rules or strengthen rules which have already been obtained. We develop a framework for describing such rules and show how we may then integrate rules at a high level without having to resort to the raw data, a useful facility for knowledge discovery where efficiency is of the essence. © 1997 John Wiley & Sons, Inc.  相似文献   
94.
Poly[bis(3‐methylphenoxy)phosphazene] was sulfonated in a solution with SO3 and solution‐cast into 100–200‐μm‐thick membranes from N,N‐dimethylacetamide. The degree of polymer sulfonation was easily controlled and water‐insoluble membranes were fabricated with an ion‐exchange capacity (IEC) as high as 2.1 mmol/g. For water‐insoluble polymers, there was no evidence of polyphosphazene degradation during sulfonation. The glass transition temperature varied from −28°C for the base polymer to −10°C for a sulfonated polymer with an IEC of 2.1 mmol/g. The equilibrium water swelling of membranes at 25°C increased from near zero for a 0.04‐mmol/g IEC membrane to 900 % when the IEC was 2.1 mmol/g. When the IEC was < 1.0 mmol/g, SO3 attacked the methylphenoxy side chains at the para position, whereas sulfonation occurred at all available aromatic carbons for higher ion‐exchange capacities. Differential scanning calorimetry, wide‐angle X‐ray diffraction, and polarized microscopy showed that the base polymer, poly[bis(3‐methylphenoxy)phosphazene], was semicrystalline. For sulfonated polymers with a measurable IEC, the 3‐dimensional crystal structure vanished but a 2‐dimensional ordered phase was retained. © 1999 John Wiley & Sons, Inc. J Appl Polym Sci 71: 387–399, 1999  相似文献   
95.
Lan HB  Wood SL  Christensen MP  Rajan D 《Applied optics》2006,45(13):2859-2870
Algorithms that use optical system diversity to improve multiplexed image reconstruction from multiple low-resolution images are analyzed and demonstrated. Compared with systems using identical imagers, systems using additional lower-resolution imagers can have improved accuracy and computation. The diverse system is not sensitive to boundary conditions and can take full advantage of improvements that decrease noise and allow an increased number of bits per pixel to represent spatial information in a scene.  相似文献   
96.
The Community Multi-Scale Air Quality (CMAQ) modeling system was used to investigate ozone and aerosol concentrations in the Pacific Northwest (PNW) during hot summertime conditions during July 1-15, 1996. Two emission inventories (El) were developed: emissions for the first El were based upon the National Emission Trend 1996 (NET96) database and the BEIS2 biogenic emission model, and emissions for the second El were developed through a "bottom up" approach that included biogenic emissions obtained from the GLOBEIS model. The two simulations showed that elevated PM2.5 concentrations occurred near and downwind of the Interstate-5 corridor along the foothills of the Cascade Mountains and in forested areas of central Idaho. The relative contributions of organic and inorganic aerosols varied by region, but generally organic aerosols constituted the largest fraction of PM2.5. In wilderness areas near the 1-5 corridor, organic carbon from anthropogenic sources contributed approximately 50% of the total organic carbon with the remainder from biogenic precursors, while in wilderness areas in Idaho, biogenic organic carbon accounted for 80% of the total organic aerosol. Regional analysis of the secondary organic aerosol formation in the Columbia River Gorge, Central Idaho, and the Olympics/Puget Sound showed that the production rate of secondary organic carbon depends on local terpene concentrations and the local oxidizing capacity of the atmosphere, which was strongly influenced by anthropogenic emissions. Comparison with observations from 12 IMPROVE sites and 21 ozone monitoring sites showed that results from the two El simulations generally bracketed the average observed PM parameters and that errors calculated for the model results were within acceptable bounds. Analysis across all statistical parameters indicated that the NW-AIRQUEST El solution performed better at predicting PM2.5, PM1, and beta(ext) even though organic carbon PM was over-predicted, and the NET96 El solution performed better with regard to the inorganic aerosols. For the NW-AIRQUEST El solution, the normalized bias was 30% and the normalized absolute error was 49% for PM2.5 mass. The NW-AIRQUEST solution slightly overestimated peak hourly ozone downwind of urban areas, while the NET96 solution slightly underestimated peak values, and both solutions over-predicted average 03 concentrations across the domain by approximately 6 ppb.  相似文献   
97.
MUC1 mucin expressed in epithelial cancer, such as prostate and breast, is aberrantly glycosylated providing unique targets for imaging and therapy. In order to create a broadly applicable construct to target these unique epitopes on metastatic cancer, we selected an antibody fragment (scFv) that binds both synthetic MUC1 core peptide and epithelial cancer cell-expressed MUC1, and developed a recombinant bivalent molecule (di-scFv). Genetically engineered modifications of the di-scFv were constructed to create five molecular versions, each having a free cysteine (di-scFv-c) at different locations for site-specific conjugation. The effects of the engineered cysteine in the varied sites were studied relative to tumor binding and polyethylene glycol-maleimide (PEG-Mal) conjugation (PEGylation). Escherichia coli production as well as binding to MUC1 core peptide, human tumor cell lines and human tumor biopsies, were comparable. However, the location of the engineered cysteine in these di-scFv-c did influence PEGylation efficiency of this free thiol; higher PEGylation efficiency occurred with this cysteine in the inter-scFv linkage. Di-scFv-c PEG, with the cysteine engineered after the fifth amino acid in the linker, was used as an example to demonstrate comparable antigen-binding to non-PEGylated di-scFv-c. In summary, novel anti-MUC1 di-scFv-c molecules can be efficiently produced, purified and conjugated by site-specific PEGylation without loss of immunoreactivity, thus providing flexible multidentate constructs for cancer-targeted imaging and therapy.  相似文献   
98.
Abstract

This special issue brings together material culture and the history of emotions to explore the emotive properties of textiles in Northwest Europe from the seventeenth to the early twentieth centuries. It is the first detailed study of the changing emotional meanings of a particular type of material - textiles - from the metallic lace adorning christening robes, to union cloth burial clothes. The six articles are contributed by historians and museum professionals from a range of disciplines. These authors harness a variety of sources and methodologies to interrogate the emotional repertoire of textiles, and the emotive process of research itself.  相似文献   
99.
Numerous antimicrobial interventions are capable of reducing the prevalence of harmful bacteria on raw meat products. There is a need to identify effective and inexpensive antimicrobial interventions that could, in practice, be used in very small meat plants because of limited financial, space, and labor resources. Eight antimicrobial compounds (acetic acid, citric acid, lactic acid, peroxyacetic acid, acidified sodium chlorite, chlorine dioxide, sodium hypochlorite, and aqueous ozone) were applied at various concentrations with small, hand-held spraying equipment, and bactericidal effectiveness was examined. Beef plate pieces were inoculated with fecal slurry containing a pathogen cocktail (Escherichia coli O157:H7, Salmonella Typhimurium, Campylobacter coli, and Campylobacter jejuni) and natural populations of aerobic plate counts, coliforms, and E. coli. Antimicrobial solutions were applied to beef surfaces via a portable, pressurized hand-held spray tank, and treated surfaces were subjected to appropriate methods for the enumeration and isolation of pathogens and hygiene indicators. Relative antimicrobial effectiveness was determined (from greatest to least): (i) organic acids, (ii) peroxyacetic acid, (iii) chlorinated compounds, and (iv) aqueous ozone. Using the equipment described, a 2% lactic acid rinse provided 3.5- to 6.4-log CFU/cm(2) reductions across all bacterial populations studied. Conversely, aqueous ozone yielded 0.02- to 2.9-log CFU/cm(2) reductions in pathogens and hygiene indicators, and did not differ significantly from a control tap water rinse (P = 0.055 to 0.731). This 2% lactic acid rinse will be subsequently combined with a previously described water wash to create a multistep antimicrobial intervention that will be examined under laboratory conditions and validated in very small meat plants.  相似文献   
100.
Recognizing and working with uncertainty in handling risk are part of both clinical practice and the policy-making process. The Department of Health recognizes the inherent challenges that uncertainty brings and employs a wide range of research mechanisms, drawing on a diverse set of disciplines, to provide an evidence base to inform both policy creation and implementation, and clinical practice. This paper describes a variety of situations and the Government response to them, each time highlighting the use of science to reduce unknowns and to support decision-making. It highlights the need for a strong research infrastructure to support the Department's requirements, and those of the NHS, both in real time to respond to emergencies and to establish a high standard of care. However, although science provides a powerful tool to reduce uncertainty, it will not always produce definitive answers and often provides the start point for a dialogue between decision makers and researchers.  相似文献   
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