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71.
Brovada is an ancient traditional product from the northeast Italian region, included in any list of typical Italian products, which is obtained by natural fermentation of turnips (Brassica rapa). Turnips are cleaned and put in vats, alternating them with a layer of grape skins. Before covering the vat a mix of water and salt or water only is added. The vegetable fermentation is a spontaneous process caused by the microorganisms present on the various components (turnip and grape skins). A total 225 lactic acid bacteria (LAB) and 63 yeasts were isolated during this natural fermentation process. The main heterofermentative population was identified as Lactobacillus spp. while the major homofermentative LAB were Pediococcus spp., Candida spp. was the main yeast present. During the first 24 h of fermentation, the pH decreased rapidly to 3.7. At different steps of fermentation the headspace aroma compounds of brovada were analyzed by solid-phase-micro-extraction/gas chromatography/flame ionization detection to define the characteristic aroma profile of this particular product.  相似文献   
72.
Oxidative stress occurs because of an imbalance in the production of reactive oxygen species. Nuts are rich in bioactive compounds, including phenolic compounds, tannins, and phytosterols. Although nuts are widely consumed because of their beneficial effects on nutrition and health, there is limited information about bioactive peptides from nuts. Pine nut and walnut-derived peptides are the most studied because these nuts contain a higher amount of protein. Different biological activities have been demonstrated for nut peptides; many of them exhibit antioxidant, anticancer, antihypertensive, antidiabetic, immunomodulatory, antiseizure, or neuroprotective activity. Recent studies have focused on increasing the bioactivity of identified bioactive peptides by applying new technologies and chemosynthetic strategies. Research tendency points to the generation of peptides with specific sequences for application in specific diseases. Nut bioactive peptides can become key functional ingredients for food, pharmaceuticals, or cosmetics.  相似文献   
73.
This paper presents estimation procedures for some robust regression methods: the Bounded-Influence estimator for both a single linear equation (Krasker and Welsch, 1982) and a linear simultaneous equation model (Krasker and Welsch, 1985); the linear version of the Huber estimator for both a single equation (Huber, 1973, 1981) and a simultaneous equations model.The procedures are written in the RATS econometric language, which is widely available on microcomputers and mainframes.  相似文献   
74.
Microwave discharges at 2.45 GHz frequency and accelerated electron beams operated at atmospheric pressure in synthetic gas mixtures containing N(2), O(2), CO(2), SO(2), and NO(x) are investigated experimentally for various gas mixture constituents and operating conditions, with respect to their ability to purify exhaust gases. An original experimental unit easily adaptable for both separate and simultaneous irradiation with microwaves and electron beams was set up. The simultaneous treatment with accelerated electron beams and microwaves was found to increase the removal efficiency of NO(x) and SO(2) and also helped to reduce the total required dose rate with approximately 30%. Concomitant removal of NO(x) ( approximately 80%) and SO(2) (>95%) by precipitation with ammonia was achieved.  相似文献   
75.
76.
Microwave plasmas at 2.45 GHz frequency operated at atmospheric pressure in synthetic gas mixtures containing N2 and CF4 are investigated experimentally for various operating conditions, with respect to their ability to destroy perfluorocompounds. It was found that the destruction and removal efficiency of the process is highly dependent on the total gas flow and concentration of CF4. Destruction and removal efficiencies of CF4 up to 98% have been achieved using 1.9 kW of microwave power at 16 L/min total flow rate.  相似文献   
77.
Since selective inhibition of the inducible form of cyclooxygenase (COX-2) might retain all the benefits of classical nonsteroidal antiinflammatory agents while avoiding the major side effects associated with inhibition of the constitutive isoform COX-1, COX-2 has become an important target for the discovery and development of new antiinflammatory drugs. To aid in the discovery and characterization of such selective inhibitors, we have applied a mass spectrometry-based screening technique, pulsed ultrafiltration mass spectrometry, using COX-2 as the target. In a blind study, 18 samples enriched with one or more inhibitors of COX-2 were evaluated. The matrixes for the test samples consisted of DMSO, r DMSO solutions of a plant extract, or a bacterial fermentation broth extract. The composition of the samples was unknown during the assays, as were the concentrations of the COX-2 inhibitors. A soluble recombinant form of human COX-2 was incubated with each sample, and then an aliquot of each mixture was injected into the stirred ultrafiltration chamber fitted with a 30000 MW cutoff ultrafiltration membrane. After the unbound and weakly bound compounds were washed away, the ligand-receptor complexes were disrupted using an acidified 10% methanol solution. The released ligands were trapped on a C18 cartridge and then identified using liquid chromatography-negative ion electrospray mass spectrometry with the trapping cartridge as the HPLC column. Neither the plant matrix nor the fermentation broth extract were found to interfere with the assay. Two or three ligands for COX-2 were identified in each sample, which included polar and nonpolar compounds and inhibitors with IC50 values ranging from 100 microM to 10 nM.  相似文献   
78.
In this paper we report a study of the electrodeposition of Cu from an acidic sulphate solution containing cetyltrimethylammonium bromide (CTAB). This investigation is based on cyclic voltammetry, in situ surface-enhanced Raman spectroscopy (SERS), Scanning Electron Microscopy (SEM) and Transmission Electron Microscopy (TEM). Adsorption of CTAB over a wide range of cathodic potentials was proved spectroelectrochemically, encompassing both conditions where compact and loose Cu grows (up to −0.4 and between −0.4 and −1 V vs. Ag/AgCl, respectively). Furthermore, we found that CTAB tends to react cathodically, undergoing the loss of the aliphatic tail at lower cathodic potentials and the formation of an allylic product at higher polarisations. CTAB deeply impacts the Cu growth mode: ordered ridges of compact Cu crystallites form at low cathodic potentials—where the electrodeposition process is strongly inhibited by CTAB adsorption—and nanoparticles grow under hydrogen-evolution conditions.  相似文献   
79.
Patients with non-small cell lung cancer, especially adenocarcinomas, harbour at least one oncogenic driver mutation that can potentially be a target for therapy. Treatments of these oncogene-addicted tumours, such as the use of tyrosine kinase inhibitors (TKIs) of mutated epidermal growth factor receptor, have dramatically improved the outcome of patients. However, some patients may acquire resistance to treatment early on after starting a targeted therapy. Transformations to other histotypes—small cell lung carcinoma, large cell neuroendocrine carcinoma, squamous cell carcinoma, and sarcomatoid carcinoma—have been increasingly recognised as important mechanisms of resistance and are increasingly becoming a topic of interest for all specialists involved in the diagnosis, management, and care of these patients. This article, after examining the most used TKI agents and their main biological activities, discusses histological and molecular transformations with an up-to-date review of all previous cases published in the field. Liquid biopsy and future research directions are also briefly discussed to offer the reader a complete and up-to-date overview of the topic.  相似文献   
80.
Abstract

The problem of heat transfer in a four channel plate heat exchanger involving the effect of unsymmetrical heat transfer in the outer two channels is studied analytically and experimentally. An energy balance over a control volume yields the governing system of differential equations that has been solved exactly for the cases of parallel flow and counterflow to give the temperature distribution in the channels. The results show that zero or even reversed heat flow may be obtained at the middle plate of the heat exchanger. Expressions for the heat exchanger efficiency and the log-mean temperature difference correction factor in terms of the heat capacity rate ratio and the number of transfer units are presented. Experiments carried out with a counterflow plate heat exchanger show reasonable agreement between the experimentally observed and the theoretically calculated efficiencies and mean driving temperature differences.  相似文献   
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