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31.
One of the major mediators of neuroinflammation in PD is tumour necrosis factor alpha (TNF-α), which, similar to other cytokines, is produced by activated microglia and astrocytes. Although TNF-α can be neuroprotective in the brain, long-term neuroinflammation and TNF release can be harmful, having a neurotoxic role that leads to death of oligodendrocytes, astrocytes, and neurons and, therefore, is associated with neurodegeneration. Apart from cytokines, a wide family of molecules with homologous structures, namely chemokines, play a key role in neuro-inflammation by drawing cytotoxic T-lymphocytes and activating microglia. The objective of the current study was to examine the levels of the serum TNF-α and CCL2 (Chemokine (C-C motif) ligand 2), also known as MCP-1 (Monocyte Chemoattractant Protein-1), in PD patients compared with healthy controls. We also investigated the associations between the serum levels of these two inflammatory mediators and a number of clinical symptoms, in particular, disease severity and cognition. Such an assessment may point to their prognostic value and provide some treatment hints. PD patients with advanced stage on the Hoehn–Yahr scale showed an increase in TNF-α levels compared with PD patients with stages 1 and 2 (p = 0.01). Additionally, the UPDRS score was significantly associated with TNF-α levels. CCL2 levels, however, showed no significant associations.  相似文献   
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In this article, we investigate reaction solvent design using COSMO‐RS thermodynamics in conjunction with computer‐aided molecular design (CAMD) techniques. CAMD using COSMO‐RS has the distinct advantage of being a method based in quantum chemistry, which allows for the incorporation of quantum‐level information about transition states, reactive intermediates, and other important species directly into CAMD problems. This work encompasses three main additions to our previous framework for solvent design (Austin et al., Chem Eng Sci. 2017;159:93–105): (1) altering the group contribution method to estimate hydrogen‐bonding and non‐hydrogen‐bonding σ‐profiles; (2) ab initio modeling of strong solute/solvent interactions such as H‐bonding or coordinate bonding; and (3) solving mixture design problems limited to common laboratory and industrial solvents. We apply this methodology to three diverse case studies: accelerating the reaction rate of a Menschutkin reaction, controlling the chemoselectivity of a lithiation reaction, and controlling the chemoselectivity of a nucleophilic aromatic substitution reaction. We report improved solvents/mixtures in all cases. © 2017 American Institute of Chemical Engineers AIChE J, 63: 104–122, 2018  相似文献   
33.
BACKGROUND: Olive oil mill waste is a serious environmental problem in the Mediterranean basin given its particular characteristics of high organic content, seasonal and localized generation, and the type of processing involved. RESULTS: Olive mill waste from a three‐phase mill was characterized by means of total analysis, availability and mobility of the pollutants in order to help the decision‐maker about possible options for its valorization and/or disposal. Water content, loss of ignition, total organic carbon, phenol index and metals concentrations were measured to fully characterize the waste. Three leaching tests (NEN 7341, EN 12457 and UNE CEN‐TS 15364 EX) were carried out to evaluate the environmental hazard of the waste material and the leachates were characterized with respect to electric conductivity, pH, heavy metals, anions and organic pollutants (phenol index and total organic carbon) according to European waste directives. The results were compared with EU regulations for inert, non‐hazardous and hazardous waste disposal. CONCLUSION: It was found that not only organic parameters must be taken into account concerning the fate of this waste material, but also the mobility of heavy metals and anions should be studied. Furthermore, stabilization/solidification processes are recommended before landfill disposal of this kind of agro‐waste material. Copyright © 2011 Society of Chemical Industry  相似文献   
34.
The influence of drop coalescence and breakup on the existence of multiple steady states is studied for a two-phase stirred isothermal reactor where the chemical reaction in the d?ispersed phase obeys the rate expression ? r = kC/(1 + KC)2. The random coalescence model developed by Curl was simulated using a modified Spielman and Levenspiel Monte Carlo technique.For certain range of the coalescence rate, Damköhler number, and dimensionless feed concentration, multiple steady states have been investigated.A special case has also been considered wherein the existence of multiple steady states for finite values of the coalescence rate is contrasted to the unique steady state solution for an infinite coalescence rate.  相似文献   
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Rapid 1,1-diphenyl-2-picrylhydrazyl (DPPH) tests are often applied to classify the scavenging activity of phenolic compounds (AH). Published analytical protocols differ in more than one experimental condition, and results for the relative order or magnitude of activity are often contradictory. In this work, parameters such as duration of test, [AH]/[DPPH] molar ratio, and solvent effects were examined and discussed. The test duration and the value of the [AH]/[DPPH] ratio did not influence the order of activity among tested antioxidants. Ethanol, commonly used as solvent in such tests, was compared with acetonitrile and tert-butyl alcohol. Solvent properties such as the ability to form hydrogen bonds with the AH seem to influence the level of the relative activity (%RSA). Higher %RSA values were observed in ethanol. The activity of the most polar compounds was affected the most, and in some cases (caffeic, dihydrocaffeic, and rosmarinic acids) the order of activity was changed owing to different kinetics. Standardization of the analytical protocol should include a 20-min reaction period and a molar ratio that permits attainment of a 60–80% RSA value for the most potent antioxidant. Solvent choice is critical for classifying activity. Safe classification can be based only on results from kinetic studies.  相似文献   
39.
The macromolecular structure of coals thermally treated at 35°C, 100°C and 150°C was investigated by dynamic penetrant transport in thin coal sections. The effects of temperature, carbon content in coal, and penetrant type on the transport mechanism were investigated. Dynamic swelling studies showed that penetrant transport into coal is a function of the average molecular weight between crosslinks, Mc. The penetrant transport mechanism at low activity is Fickian diffusion. The transport mechanism deviates from Fickian diffusion to anomalous transport, when the carbon content in coal and penetrant activity increase. Variations of the diffusion coefficients and relaxation constants were determined using a diffusion/relaxation coupled model.  相似文献   
40.
The conductivity and structure of 8-mol%-yttria-stabilized zirconia with additions of nickel oxide has been investigated, both in the as-prepared state and after reduction of NiO in hydrogen. During reduction at 1000°C, the conductivity decreases by 40%–50% and most of the NiO dissolved in the zirconia is exsolved in the form of nickel particles. This is accompanied by the formation of tetragonal zirconia precipitates of size 10–40 nm and by an increase in the lattice parameter. On reoxidation in air at 1000°C, the change in lattice parameter is partly reversed, but the conductivity shows no further changes.  相似文献   
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