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441.
We report on the biofunctionalization of zinc oxide nanowires for the attachment of DNA target molecules on the nanowire surface. With the organosilane glycidyloxypropyltrimethoxysilane acting as a bifunctional linker, amino-modified capture molecule oligonucleotides have been immobilized on the nanowire surface. The dye-marked DNA molecules were detected via fluorescence microscopy, and our results reveal a successful attachment of DNA capture molecules onto the nanowire surface. The electrical field effect induced by the negatively charged attached DNA molecules should be able to control the electrical properties of the nanowires and gives way to a ZnO nanowire-based biosensing device.  相似文献   
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Multiple sclerosis (MS) is an inflammatory autoimmune disease characterized by imbalanced immune regulatory networks, and MS patient-derived T effector cells are inefficiently suppressed through regulatory T cells (Treg), a phenomenon known as Treg resistance. In the current study we investigated T cell function in MS patients before and after interferon-beta therapy. We compared cytokine profile, responsiveness for Treg-mediated suppression ex vivo and evaluated reactivity of T cells in vivo using a humanized mouse model. We found that CD4+ and CD8+ T cells of therapy-naive MS patients were resistant to Treg-mediated suppression. Treg resistance is associated with an augmented IL-6 production, enhanced IL-6 receptor expression, and increased PKB/c-Akt phosphorylation. These parameters as well as responsiveness of T cells to Treg-mediated suppression were restored after interferon-beta therapy of MS patients. Following transfer into immunodeficient mice, MS T cells induced a lethal graft versus host disease (GvHD) and in contrast to T cells of healthy volunteers, this aggressive T cell response could not be controlled by Treg, but was abolished by anti-IL-6 receptor antibodies. However, magnitude and lethality of GvHD induced by MS T cells was significantly decreased after interferon-beta therapy and the reaction was prevented by Treg activation in vivo. Our data reveals that interferon-beta therapy improves the immunoregulation of autoaggressive T effector cells in MS patients by changing the IL-6 signal transduction pathway, thus restoring their sensitivity to Treg-mediated suppression.  相似文献   
444.
ABB has advanced catalysis with micro-engineered catalyst (MEC) systems by providing a uniquely small particle size on a formable catalyst support through the integration of catalysis and reaction engineering. A mechanically strong catalytic web of micro-fibers has been engineered and shaped utilizing both computational fluid dynamics (CFD) and cold flow experiments to optimize flow characteristics. This article discusses techniques used for the development of novel catalytic structured packings for catalytic distillation applications. CFD models (verified through experiments performed on small-sized structures) were shown to be of great utility in screening new structure ideas. Results will illustrate achievement of both high gas–liquid contacting and bulk mixing at low pressure drop with the potential to provide enhanced catalyst utilization by taking advantage of the intrinsic MEC properties, particularly its high porosity and exposed geometric fiber and catalyst surface area. This was shown by the successful testing of one of these catalyzed structures in the selective hydrogenation of C4 acetylenes.  相似文献   
445.
The influence of the viscosity of the ceramic slip on the manufacture of ceramic foams by the polymer sponge method was studied. The foams were coated with silicalite (100 nm) and HZSM-5 (650 nm) crystals by dipping them in a zeolite suspension without binder additives. The amount of zeolite loaded can be controlled through the zeolite content of the dipping suspension. Uniform coatings are achieved starting with about 1 g zeolite/m2 foam.  相似文献   
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448.
Addition of α-Ketoenamines to 2-Acetyl-p-benzoquinone Addition of 2-morpholino-2-cyclohex-1-en-one 2 to 2-acetyl-quinone 1 yields benzo[c][4 H]chromen-4,7,10-trion 4 which is unstable and rearranges to 5. 4 is converted to 3-(2,5-dihydroxy-phenyl)-2-morpholino-2-cyclohex-1-en-on 3 thermically and to dibenzo[b,d]furan-4-on 7 acid catalyzed. The structure of 7 is secured by independent synthesis. Dibenzo[b,d]furan-4-on 14 is the product of reaction from 2-(p-toluidino)-2-cyclohex-1-en-on 9 and 1 with benzo[c][4 H]chromen-4,7,10-trion 10 as intermediate. By proton catalysis 5-acetyl-6-hydroxy-carbazol-1-on 13 and 4-oxo-cyclohexa[c]isochinolinium hydrochlorid 15 is obtained from 10 . 1 H-cyclopenta[d]furan-3-on 17 is formed by addition of 2-(p-toluidino)-2-cyclopent-1-en-on 16 to 1 . It is rearranged by proton catalysis to 3-oxo-1 H-cyclopenta[c]isochinolinium salt 18 . Reaction of cyclopentan-1,2-dione and 1 yields 3 aH-cyclopenta[c]isochromen-3,6,9-trion 20 , rearranging to 1 H-cyclopenta[b]benzo[d]furan-3-on 21 . The stereochemistry of adducts is discussed in connection with the course of the reaction, spectroscopical evidence, molecular modelling and calculation of HOMO/LUMO and AO-coefficients.  相似文献   
449.

Scope

LTP-syndrome is characterized by sensitization (IgE) to multiple non-specific lipid transfer proteins (nsLTPs) with a variable clinical outcome. The treatment is primarily based on offending food avoidance. However, the determination of Pru p 3-specific IgE is currently the main diagnostic tool to assess sensitization to nsLTPs. Herein, the study evaluates improvement of LTP-syndrome diagnosis and clinical management using a new IgE multiplex-immunoblot assay with a high diversity of food nsLTPs.

Methods and results

An EUROLINE-LTP strip with 28 recombinant nsLTPs from 18 allergenic sources is designed. In total the study investigates 38 patients with LTP-syndrome and compares results from the nsLTPs (LTP-strip) with the respective food extracts of Prick-by-prick (PbP) testing. The agreement exceeds 70% for most nsLTPs, e.g., Pru p 3 (100%), Mal d 3 (97%), Pru av 3 (89%), Pha v 3 isoforms (87%/84%), Ara h 9 (82%), Cor a 8 (82%), and Jug r 3 (82%). The functionality and allergenic relevance of nine recombinant nsLTPs are proven by Basophil activation testing (BAT).

Conclusions

The new IgE multiplex-immunoblot nsLTP assay shows a good diagnostic performance allowing culprit food assessment. Negative results from LTP-strip may indicate potentially tolerable foods, improving diet intervention and patients’ quality of life.  相似文献   
450.
Membrane processes are considered as comparably mild separation processes offering the potential for significant energy savings compared with azeotropic distillation processes. Despite higher investment and material costs, they are of particular interest for improving the energy efficiency in the chemical industry. However, energy savings of more than 20%–30% are rarely reported and even a general superiority can be disputed. To further elucidate this controversial, the current study pursues a quantitative assessment of the thermodynamic efficiency of pervaporation and vapor permeation processes with stand-alone distillation and hybrid membrane-assisted distillation processes for the separation of azeotropic mixtures. The results confirm the case-dependent potential of distillation processes to outperform membrane-assisted separations in terms of energy efficiency, considering proper heat integration. Although energy efficiency is becoming significantly important, it should be considered in the context of economic performance to determine an optimal trade-off and to select the best process alternative during conceptual process design.  相似文献   
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