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101.
Chamaerops humilis L. var. argentea André (C. humilis) date palm seeds are an underutilized source of vegetable oil, and no studies describing their physicochemical characteristics to indicate the potential uses of this seed or seed oil have been reported. The oil content of the seeds is about 10%, mainly composed of oleic acid (38.71%), lauric acid (21.27%), linoleic acid (15.15%), palmitic acid (9.96%), and stearic acid (7.17%). The tocol (tocopherols and tocotrienols) content is 74 mg/100 g, with δ‐tocotrienol as the major contributor (31.91%), followed by α‐tocotrienol (29.37%), γ‐tocopherol (20.16%), and γ‐tocotrienol (11.86%). Furthermore, this oil shows high thermal stability. The differential scanning calorimetery curves revealed that the melting and crystallization points are 9.33 °C and –15.23 °C, respectively.  相似文献   
102.
Total hydrocarbon composition and content of whole peanuts from three Tunisian varieties of peanut (two cultivars: AraC (Virginia type), AraT (Valencia type) and a wild one: AraA) were investigated during maturation. The results show that 30 hydrocarbons were identified from the wild AraA species, while only 27 hydrocarbon were detected in the cultivar ones. The hydrocarbon fraction is essentially composed of squalene, n-alkenes especially nC14=, nC16=, nC18=, nC20= and nC22=, n-alkanes such as nC16, nC17, nC18, nC25, nC26 and nC27, and branched saturated hydrocarbon noted (HC1, HC2 and HC3). Among the hydrocarbon components, generally the wild variety AraA presents the highest content of phytochemical squalene during maturation, whereas a maximum was detected from cultivar AraT at 12 days after podding (815.45 mg/100 g of oil). At maturity, the maximum level is reached at about 346.74 mg/100 g of oil for AraA. During maturity, wild AraA is considered to be an excellent source of squalene like olive and pumpkin oil.  相似文献   
103.
Through years of development Content Networks (CN) have become more sophisticated and more technically diverse. Modern CN are designed to be more adaptive to communication environment, devices and user requirements. However, one open issue is the still fluctuating quality of service provision. As a result user experience can be negatively affected. In order to maintain a satisfactory level of user experience it is crucial to develop a feasible solution to measure the extent to which video services meet users?? expectation. Assessing video quality with respect to users?? subjective opinions is a complex task. In this paper we address challenges of this task and design an integrated framework using a number of comprehensive functional modules. Our framework integrates objective quality assessment models of Artifacts Measurement (AM) and Quality of Delivery (QoD) approaches. Only the fittest models are activated by the framework considering requirements of individual evaluation tasks. We also introduce our recent work of realising key functional modules of the framework. Joint subjective experiments between two institutes have also been carried out for the purpose of model implementation and evaluation. Results from experiments verify the concept of an integrated framework and show the effectiveness of its key modules in estimating the quality level of video services.  相似文献   
104.
The phenolic fraction of flaxseed oil was quantified during the development of three varieties (H52, O116 and P129). Seed samples were collected at regular intervals from 7 to 56 days after flowering (DAF). During oilseed processing, less polar compounds are co-extracted with oil. The methanolic extracts were obtained by solid phase extraction. Separation of phenolic compounds was conducted by high-performance liquid chromatography-mass spectrometry. The main phenolic compounds detected during maturation were: diphyllin, pinoresinol, matairesinol, secoisolariciresinol, vanillic acid, ferulic acid and vanillin. The highest amount of lignans (6.74 mg of analyte/kg of flaxseed oil) was detected at 7 DAF in P129 variety. The maximum level of phenolic acids (2.57 mg of analyte/kg of flaxseed oil) was reached at 7 DAF in P129 which had also the highest content of simple phenols (1.37 mg of analyte/kg of flaxseed oil) at the same date after flowering. At full maturity, the content of phenolic compounds in three varieties ranged from 0.26 to 0.36 mg of analyte/kg of flaxseed oil. The highest content of total phenolic compounds using the Folin–Ciocalteu method was detected in P129 variety (196.42 mg CAEs/kg of flaxseed oil) at 7 DAF. Results of this study indicate that flaxseed oils contain different amounts of phenolic compounds using different methods.  相似文献   
105.
Aggregated traffic traces are commonly used in network engineering for QoS or performance parameters evaluation. Many performance models come from such aggregated traces. However, real traffic is a marked point process combining two processes: one for the arrival times of packets and the other for their size in bytes. This paper deals with assessing whether aggregated traces are a good representation of real traffic. Based on the analysis of many traffic traces, and focusing only on loss probability, it is shown that the packet drop probability obtained for the aggregated traffic traces can significantly differ from the real packet drop probability obtained for the real traffic traces. Then, a solution which enables one to obtain correct loss probability based on aggregated traffic traces is proposed by determining the correct aggregation scale and traffic parameters to be applied.  相似文献   
106.
The extraction of Stipa tenacessima L Alfa fibers was performed using alkaline procedure to remove noncellulosic substances such as pectin, lignin, and hemicellulose. The degree of polymerization of extracted and purified Alfa fibers was determined using viscosimetric method and extracted fibers were used as a cationic ion‐exchange material by treating alkali‐cellulose of Alfa with EpoxyPropylTriMethylAmmonium Chloride (EPTMAC). Evidence of grafting was monitored using IR spectroscopy and thermogravimetry analysis. Two EPTMAC‐Alfa fibers with different %N were prepared and tested as adsorbent of four acid dyes: Acid Blue 25 (AB 25), Acid Yellow 99 (AY 99), Reactive Yellow 23 (RY 23), and Acid Blue 74 (AB 74). The modeling of the adsorption isotherms using Langmuir, Freundlich, and Jossens allowed the determination of isotherm constants leading to characterize the different adsorbent/adsorbate systems prepared. Thermodynamic parameters such as change in free energy (ΔG), the enthalpy (ΔH), and the entropy (ΔS) were also evaluated. Additionally, regeneration of adsorbent solid supports by desorption process in fixed bed column was reported. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010  相似文献   
107.
The present investigation was carried out for the analysis of hydrocarbon compounds of Tunisian Meski olives. The hydrocarbon fraction of the oils was found to contain twelve n‐alkanes (C22–C36) and squalene. Results from the quantitative characterisation of the oils revealed that squalene was the most abundant hydrocarbon compound, at all development stages of Meski olive, accounting for more 92% of total hydrocarbons. Pentacosane (C25), heptacosane (C27) and tricosane (C23) represented the major compounds of n‐alkanes. The highest accumulation of n‐alkanes and squalene was observed at early stages of olive development [before 21st week after the flowering date (WAFD)]. The greatest decrease of these components occurred between 21st and 26th WAFD of the olives. At complete maturity of the fruit, the level of squalene and total n‐alkanes was 126.52 and 9.13 mg per 100 g oil, respectively. Hence, the content of n‐alkanes and squalene was remarkably influenced by the ripeness process of olive.  相似文献   
108.
The subject of the paper is the comparative research on the carrying capacity of the conical interference-fit joints and the interference-fit joints with the laser reinforcement paths. The calculations of strain and stress distribution in the shaft neck and the bush were carried out for three stages: during the joining process, after the interference and after the application of torsional moment. The FEM was used. The dependences of the joint carrying capacity on the interference force were determined and experimental tests of the capacity of the conical interference-fit joints were carried out. The numerical calculation showed the increase in the capacity of the conical interference-fit joints with the laser reinforcement zones in comparison with the standard joints by 50% in the case of the same axial displacement. Greater capability (about 25%) of this joint was achieved from experimental tests in comparison to one without paths.  相似文献   
109.
A high-performance liquid chromatographic method coupled with mass spectrometry was used to characterise the natural phospholipid (PL) classes and molecular species in flaxseed oils. The PL fraction included phosphatidylethanolamine (PE) (27–40%), phosphatidylinositol (PI) (29–32%), phosphatidylcholine (PC) (7–18%), lysophosphatidylcholine (LPC) (8–21%), phosphatidylglycerol (PG) (1–4%) and phosphatidic acid (PA) (1–9%). The distribution of fatty acids was found to differ between phospholipids. Stearic acid was mainly present in the form of PC and LPC. Palmitic acid was present in the most abundant molecular species in PI, PG and PA whereas linoleic acid formed the most abundant molecular species in PE.  相似文献   
110.
The effect of quince (Cydonia oblonga Miller) polyphenolic extract on preserving mackerel (Scomber scombrus) fillets during refrigerated (4 °C) storage for 11 days was investigated. The quince extract, mainly consisted of procyanidin B dimer (50.8%) and hydroxycinnamic acids (36.62%), was found to quench 2,2‐diphenyl‐1‐picrylhydrazyl radicals by nearly 59.3%. As deduced from the lower peroxide value of the fillet fat fraction and the inhibition of thiobarbituric acid reactive substances formation, the quince extract (8.9 ± 0.4 mg phenolics mL?1) was found to prevent fish oil from oxidative deterioration compared to control samples. Moreover, the extract was found to be active for in vitro inhibiting the growth of a range of food‐borne bacteria, including Vibrio fluvialis, a halophilic bacterium responsible for a relevant number of sporadic gastroenteritis attributed to contaminated seafood. The minimal inhibition and bactericide concentration (MIC, MBC) values were about 0.37–1.2 mg of polyphenols mL?1. In a second experiment, following cold smoking of fillets, sensory attributes firmness, astringency, acidity, colour and odour were analysed. The use of multivariate statistical methods (cluster analysis and principal component analysis) revealed no significant differences between samples pre‐treated and non‐pre‐treated (control) with the quince‐phenolic extract.  相似文献   
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