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71.
The objective of this study was to determine i) if Camembert cheese micro-organisms could be detected in fecal samples after regular consumption by human subjects and ii) the consequence of this consumption on global metabolic activities of the host colonic microbiota. An open human protocol was designed where 12 healthy volunteers were included: a 2-week period of fermented products exclusion followed by a 4-weeks Camembert ingestion period where 2x40 g/day of Camembert cheese was consumed. Stools were collected from the volunteers before consumption, twice during the ingestion period (2nd and 4th week) and once after a wash out period of 2 weeks. During the consumption of Camembert cheese, high levels of Lactococcus lactis and Leuconostoc mesenteroides were measured in fecal samples using real-time quantitative PCR, reaching median values of 8.2 and 7.5 Log(10) genome equivalents/g of stool. For Ln. mesenteroides, persistence was observed 15 days after the end of Camembert consumption. The survival of Geotrichum candidum was also assessed and the fecal concentration reached a median level of 7.1 Log(10) CFU/g in stools. Except a decreasing trend of the nitrate reductase activity, no significant modification was shown in the metabolic activities during this study.  相似文献   
72.
The feasibility of quantifying the perceived active ingredient (P57) in Hoodia gordonii raw material using Fourier transform near- and mid-infrared spectroscopy combined with chemometric techniques was investigated. The concentration of P57 (a triterpene glycoside) was determined in 146 plant samples with liquid chromatography coupled to mass spectrometry and these values were used to develop a calibration model based on the partial least squares projections to latent structures (PLS) and orthogonal projections to latent structures (O-PLS) regression algorithms. The performance of each calibration model was evaluated according to the root mean square error of prediction (RMSEP) and correlation coefficient (R2). The PLS model with 2nd derivative pre-processing predicted P57 content based on the FT-NIR spectra with the best accuracy and a correlation coefficient (R2) value of 0.9629 and the lowest RMSEP of 0.03%. These results demonstrated that FT-NIR spectroscopy can be used to rapidly quantify P57 in H. gordonii raw material with high accuracy.  相似文献   
73.
The metallopolymer polyaniline-silver (PANI-Ag) was synthesized and used as conductive filler in crosslinked diglycidyl ether of bisphenol A (DGEBA) epoxy network. The hybrid organic/inorganic PANI-Ag powders were successfully synthesized via in situ chemical oxidation of polyaniline-emeraldine base (PANI-EB) by the capped Ag+ on the polyaniline-emeraldine base (PANI-EB) surface. The UV–Vis and FT-IR spectra confirmed the pernigraniline structure (PN) of PANI in the hybrid PANI-Ag. The PANI-Ag dispersion in epoxidic matrix was analyzed by optical microscopy (OM). The images analysis from OM showed that the particle agglomerate size of the metallopolymer increased with increasing PANI-Ag concentration in the DGEBA composite, owing to the aggregation effect. The dc conductivity and impedance spectroscopy of the DGEBA/PANI-Ag composite was measured at different PANI-Ag concentrations in the DGEBA network. The electrical dc conductivity of the PANI-Ag was 35.1 S cm−1 and was dependent of the PANI-Ag concentration in DGEBA matrix. The real and imaginary part of impedance complex measurements indicates a strong interfacial polarization at low frequency for both PANI-Ag and DGEBA/PANI-Ag, respectively. The imaginary part of impedance complex Im(Z) data decrease with the PANI-Ag hybrid concentration in the frequencies range of 102–106 Hz. The dependence of the Im(Z) on the frequency exhibited a relaxation process in both, PANI-Ag and DGEBA/PANI-Ag composite with 10 phr of PANI-Ag powder.  相似文献   
74.
In 1994, a collaborative programme was set up between the University of Surrey and the Chilean Air Force to design and build a low-cost 50 kg microsatellite with instrumentation capable of monitoring the distribution and concentration of stratospheric ozone, particularly over Chilean territory. This resulted in the joint design and development of the ozone-layer monitoring experiment (OLME), which was flown on board the resultant FASat-Bravo microsatellite, launched in July 1998 into an 820 km altitude Sun-synchronous orbit. The nadir-pointing OLME measures the solar ultraviolet light backscattered from the atmosphere in four spectral bands. From these raw radiometric data, total column ozone concentrations can be deduced. Since the launch, a series of high-spatial-resolution measurements have been made over Chilean scientific stations, while continuous low-spatial-resolution measurements have been used to provide global coverage. To date, the University of Surrey has concentrated on these global measurements, and has used a simplified ozone retrieval algorithm to check the results qualitatively against ozone maps produced by NASA's Earth Probe Total Ozone Mapping Spectrometer (TOMS) payload. These initial results look promising, with apparently good correlation between the two datasets. A novel, more-complex retrieval algorithm has been applied to the high-resolution data, and early results have shown agreement with the TOMS.  相似文献   
75.
Multivalent molecules, i.e.?scaffolds presenting multiple copies of a suitable ligand, constitute an emerging class of nanoscale therapeutics. We present a novel approach for the design of multivalent ligands, which allows the biofunctionalization of polymers with proteins or peptides in a controlled orientation. It consists of the synthesis of water-soluble, activated polymer scaffolds of controlled molecular weight, which can be biofunctionalized with various thiolated ligands in aqueous media under mild conditions. These polymers were synthesized by ring-opening metathesis polymerization (ROMP) and further modified to make them water-soluble. The incorporation of chloride groups activated the polymers to react with thiol-containing peptides or proteins, and the formation of multivalent ligands in aqueous media was demonstrated. This strategy represents a convenient route for synthesizing multivalent ligands of controlled dimensions and valency.  相似文献   
76.
Examined the relationship between aphasia type and lesion site in 80 subcortical stroke patients. Ss were classified as affected by aphasia, dysarthria, and nonaphasia, nondysarthria. Sites of lesions were identified by means of computerized tomography (CT) scan. No correlation between site of lesions and category group was found. Lesions of the same subcortical structures yielded different neurolinguistic impairment, whereas comparable linguistic patterns were observed with lesions of different deep areas. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
77.
The authors investigated relationships between marijuana and inhalant use and several cultural and demographic factors in Anglo American and Hispanic American adolescents (N=1,094). Outcome measures assessed lifetime and 30-day marijuana and inhalant use. Predictors and covariates used in logistic regression analyses were region, grade, gender, knowledge, acculturation, familism, and parental monitoring. Hispanic Americans exhibited higher usage across all measures. In this group, high acculturation was associated with low marijuana, but high inhalant, use. Across all participants, positive family relations and parental monitoring were strongly associated with attenuated marijuana use hut only among those most knowledgeable about drugs. Familism and monitoring were not associated with diminished usage among the less knowledgeable. For inhalants, monitoring combined with high knowledge or high familism was associated with diminished usage. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
78.
Given the increasing number of antibiotic-resistant bacteria and the need to synthesize new antimicrobials, silver has attracted interest in the scientific community because of its recognized antimicrobial activity. This study aimed to evaluate the antimicrobial effects of silver nanoparticles (NP) obtained by a new method and tested at concentrations of 6 μg/ml and 60 μg/ml against the species Staphylococcus aureus, Listeria innocua, Salmonella Choleraesuis, Pseudomonas aeruginosa, Escherichia coli, and Bacillus cereus. The ability of these nanoparticles to remove or kill vegetative cells adhered to stainless steel surfaces was also evaluated. We observed that the NP obtained with the new method, concentrated silver nanoparticles (CNP), and silver nanoparticles with added sodium chloride (NPNaCl) had high antimicrobial activities (P < 0.05). We also verified that the most effective condition for the removal of P. aeruginosa cells on stainless steel coupons (10 by 10 mm) was immersion of the surfaces in CNP. The CNP treatment produced a 5-log reduction of the microbial population after 30 to 60 min of immersion. The CNP treatment also performed better than water and sodium carbonate, a compound commonly applied in clean-in-place procedures in the food industry, in removing adherent B. cereus cells from stainless steel cylinders. Therefore, these results suggest that NP synthesized by a new procedure may be used as antimicrobials in the food industry, for example, for the sanitization of utensils that come into contact with foods.  相似文献   
79.
This study investigated the effects of heat‐moisture treatment (HMT) on the resistant starch content and thermal, morphological, and textural properties of rice starches with high‐, medium‐ and low‐amylose content. The starches were adjusted to 15, 20 and 25% moisture levels and heated at 110°C for 1 h. The HMT increased the resistant starch content in all of the rice starches. HMT increased the onset temperature and the gelatinisation temperature range (Tfinish–Tonset) and decreased the enthalpy of gelatinisation of rice starches with different amylose contents. This reduction increased with the increase in the moisture content of HMT. The morphology of rice starch granules was altered with the HMT; the granules presented more agglomerated surface. The HMT affected the textural parameters of rice starches; the high‐ and low‐amylose rice starches subjected to 15 and 20% HMT possessed higher gel hardness.  相似文献   
80.
This study addressed the correlation between physical characteristics of double emulsions and sensory perception, as the microstructure of these systems may provide the mechanism to understanding the initial cause of the altered salty taste. Thus, double emulsions (W/O/W) were prepared using different volumes of the internal aqueous phase while maintaining the same fat and sodium contents in the evaluated systems. Polyglycerol polyricinoleate (PGPR) and tween 80 were used as hydrophobic and hydrophilic emulsifiers, respectively. After preparation, the samples were stored at 25 °C for 4 days and submitted to analysis of optical microscopy, distribution and polydispersity of the oil droplets size, electrical conductivity, rheological behaviour and sensorial analysis. It was found that the use of different emulsifier concentrations (PGPR) did not influence the physical characteristics of the emulsions with the same formulation, but emulsions with different internal aqueous phase concentrations presented different results. These distinct characteristics may have influenced sensorial perception, as the emulsion with higher internal phase concentration was considered saltier. Thus, it can be concluded that structural differences of the double emulsions can be used to decrease the sodium contents without perceivable changes in salty taste.  相似文献   
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