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21.
Aspergillus flavus is frequently found in food, producing a wide variety of toxins, aflatoxins being the most relevant in food safety. A specific PCR-based protocol for this species is described which allowed discrimination from other closely related species having different profiles of secondary metabolites from the Aspergillus Section Flavi, particularly A. parasiticus. The specific primers were designed on the multi-copy internal transcribed region of the rDNA unit (ITS1-5.8S-ITS2 rDNA) and were tested in a wide sample of related species and other fungal species commonly found in food. The PCR assay was coupled with a fungal enrichment and a DNA extraction method for wheat flour to enhance the sensitivity of the diagnostic protocol. The results indicated that the critical PCR amplification product was clearly observed for wheat flour contaminated by 102 spores after 16 h of incubation.  相似文献   
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Thermal conductivity of free‐standing reduced graphene oxide films subjected to a high‐temperature treatment of up to 1000 °C is investigated. It is found that the high‐temperature annealing dramatically increases the in‐plane thermal conductivity, K, of the films from ≈3 to ≈61 W m?1 K?1 at room temperature. The cross‐plane thermal conductivity, K, reveals an interesting opposite trend of decreasing to a very small value of ≈0.09 W m?1 K?1 in the reduced graphene oxide films annealed at 1000 °C. The obtained films demonstrate an exceptionally strong anisotropy of the thermal conductivity, K/K ≈ 675, which is substantially larger even than in the high‐quality graphite. The electrical resistivity of the annealed films reduces to 1–19 Ω □?1. The observed modifications of the in‐plane and cross‐plane thermal conductivity components resulting in an unusual K/K anisotropy are explained theoretically. The theoretical analysis suggests that K can reach as high as ≈500 W m?1 K?1 with the increase in the sp2 domain size and further reduction of the oxygen content. The strongly anisotropic heat conduction properties of these films can be useful for applications in thermal management.  相似文献   
24.
Aortic stenosis (AS) is a fibrocalcific disease of the aortic valves (AVs). Sex-differences in AS pathophysiology have recently been described. High levels of fatty acid-binding protein 4 (FAPB4) in atherosclerotic plaques have been associated with increased local inflammation, endothelial dysfunction, and plaque vulnerability. FABP4 pharmacological blockade has been shown to be effective for the treatment of atherosclerosis by modulating metabolic and inflammatory pathways. We aimed to analyze the sex-specific expression of FABP4 in AS and its potential role as a therapeutic target. A total of 226 patients (61.5% men) with severe AS undergoing surgical AV replacement were recruited. The FABP4 levels were increased in the AVs of AS patients compared to the control subjects, showing greater expression in the fibrocalcific regions. Male AVs exhibited higher levels of FABP4 compared to females, correlating with markers of inflammation (IL-6, Rantes), apoptosis (Bax, caspase-3, Bcl-2), and calcification (IL-8, BMP-2 and BMP-4). VICs derived from AS patients showed the basal expression of FABP4 in vitro. Osteogenic media induced upregulation of intracellular and secreted FABP4 levels in male VICs after 7 days, along with increased levels of inflammatory, pro-apoptotic, and osteogenic markers. Treatment with BMS309403, a specific inhibitor of FABP4, prevented from all of these changes. Thus, we propose FABP4 as a new sex-specific pharmacological therapeutic target in AS.  相似文献   
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Multimedia Tools and Applications - In this paper, we will present a study concerning the understanding of the needs of people using Internet in order to access to multilingual information. In...  相似文献   
26.
Suitable proportions of the solvent mixture benzene:methanol:aqueous hydrochloric acid to yield the spherically agglomerated crystals of cyanin have been found. The physicochemical properties and dissolution rate of the agglomerates, in comparison with the crystals obtained by a conventional method, have been analysed. No change in the crystalline form of the basic crystals was found in acid conditions, after agglomeration. The dissolution rate of spherical agglomerates did not decrease as much as predicted from their low specific surface areas because of their improved wettability. The crystallization speed would not only avoid colour loss during the isolation and purification of anthocyanins from their natural sources, but also would increase production, save time and cost. On the other hand, a decrease in the specific surface areas will reduce powder hydroscopicity with subsequent technological and stability advantages.  相似文献   
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Keeping rheological, mechanical and thermal properties of virgin poly(ethylene terephthalate), PET, is necessary to assure the quality of second-market applications. A comparative study of these properties has been undertaken in virgin, mechanical recycled and commercial recycled PET samples.  相似文献   
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Working time accounts (WTAs) provide flexibility to a company to adjust the capacity to the demand by planning, for each period and each worker, an appropriate number of working hours. Under this scheme, every worker has a balance that can be positive (the company owes hours to the worker), zero or negative (the worker owes hours to the company). Credit (or debit) hours are compensated by working less (or more) hours than the reference value in the subsequent periods. This scheme is especially useful for companies dealing with demand fluctuations, because WTA balances can take any value, provided that these belong to a given bounded interval. Other conditions that affect the number and distribution of working hours may be established either in law or in the WTA agreement. This paper proposes a new mathematical model for planning production, inventory levels, working time and temporary closures in a manufacturing company operating under a standard WTA scheme. The results of the computational study show that the model is an appropriate tool not only for planning but also for helping in the bargaining process (different WTA scheme configurations could be evaluated with the model).  相似文献   
30.
In this work, we have accomplished the optimization of focused ultrasound extraction and supercritical fluid extraction (SFE) of volatile oils and phenolic compounds from aromatic plants such as rosemary, oregano, and chamomile. The response surface analysis was the overall procedure to tackle this work. On the one hand, the focused ultrasound extraction method of volatile compounds was studied based on the use of cyclohexane as extractant (chamomile required cyclohexane:isopropanol (95:5)), and three parameters were optimized (cycles, amplitude, and time) for each plant. The quantification of the volatile compounds was performed by means of GC?×?GC-MS analysis and the volatile oil concentration rounded 10–310 μg/g for the oregano; 7–2,920 μg/g for the rosemary, and 0.8–244.2 mg/g for the chamomile. In the SFE method, four parameters were studied (oven temperature, pressure, CO2 flow, and EtOH?%). The total polyphenol content was determined by Folin–Ciocalteu obtaining values from 1,000 to 12,000 mg gallic acid equivalent (GAE)/g plant. The antioxidant capacity was measured by Trolox equivalent antioxidant capacity obtaining values from 1.1 to 46.7 μmol Trolox equivalent/g plant.  相似文献   
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