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71.
Ravinder Kaushik Bhawana Sachdeva Sumit Arora 《International Journal of Dairy Technology》2017,70(2):269-276
Two levels (500 and 600 ppm) of calcium (calcium phosphate and calcium citrate) along with vitamin D2 (600 IU/L) were fortified in milk for dahi preparation. pH, water‐holding capacity and syneresis of fortified dahi were not affected significantly (P > 0.05). However, acetaldehyde content decreased and setting time increased upon fortification. Microbial count significantly (P < 0.05) decreased in calcium phosphate‐fortified dahi, whereas no difference was observed in calcium citrate‐fortified dahi. Firmness and viscosity decreased in calcium phosphate‐fortified dahi, whereas it increased in calcium citrate‐fortified dahi as compared to control. All dahi samples showed good sensory acceptability. 相似文献
72.
Sharad Babu Pillai Shweta D. Dabhi Prafulla K. Jha 《International Journal of Hydrogen Energy》2018,43(47):21649-21654
We present a systematic ab initio study of atomic hydrogen and oxygen adsorption on bismuthene monolayer and its alloys with arsenic and antimony through electronic structure calculations based on density functional theory within generalized gradient approximation. We systematically investigated the preferable adsorption site for hydrogen and oxygen atom on 2D Bi, BiAs and BiSb. It was found that the hydrogen atom prefers top site of bismuth atom and oxygen atom prefers to reside in the hexagonal ring of these 2D bismuth alloys. The free energy calculated from the individual adsorption energy for each monolayer subsequently guides us to predict the best suitable catalyst among the considered 2D monolayers. The 2D BiSb serves better for hydrogen evolution reaction (HER) with hydrogen adsorption energy as ?1.384 eV while 2D BiAs is suitable for oxygen evolution reaction (OER) with oxygen adsorption energy as ?1.092 eV. We further investigated the effects of the adsorbate atom on the electronic properties of 2D Bi, BiAs and BiSb. The adsorption of oxygen on 2D BiAs and BiSb was shown to reduce the bulk band gap by 40.56 and 67.79% respectively which will be advantageous for the observation of Quantum Spin Hall effect at ambient conditions. 相似文献
73.
In the present study, excitation energy transfer between the dye pair 9 amino acridine hydrochloride hydrate (9AAHH)–acriflavin and the ternary 9AAHH–acriflavin–rhodamine B (RB) dye system doped in poly-vinyl alcohol (PVA) films was investigated at room temperature. For 9AAHH–acriflavin dye pair, the energy transfer parameters, viz overlap integral ΩDA and critical transfer distance R OA, equalling 1.4×10?13 l cm3 mol?1 and 45.23 Å, respectively, have been obtained. Energy transfer from 9AAHH to RB via acriflavin has also been investigated. These two and three dyes doped transparent polymer films of PVA can be used as efficient materials in luminescent solar collectors. 相似文献
74.
The effect of polymer cross-linkages on thermal degradation of silica/poly (methyl methacrylate) (PMMA) nanocomposites is investigated using a single novel nanoparticle. Nanosilica surface treated with KH570, an organic surface treatment capable of free-radical polymerisation, was used to cross-link PMMA via an in situ method. Scanning electron microscopy was used to characterise nanosilica before use, while X-ray diffraction confirmed silica was well dispersed in PMMA. Thermogravimetric analysis (TGA) results showed that thermal degradation of silica cross-linked nanocomposites was significantly stabilised compared to PMMA, with a 30% reduction in the peak mass loss rate. Kinetic studies revealed the degradation of nanocomposites in this work abide by first-order kinetics, with an increase in the degradation activation energy of approximately 100?kJ?mol?1. This is nearly double the improvement compared to conventional PMMA-silica nanocomposites in literature, showing dramatic enhancements to thermal stability. Analysis of high-temperature residuals from TGA tests suggest that cross-linked silica have increased char yields when compared with both PMMA and traditional silica nanocomposites. Cone Calorimetry results showed the materials in this work have reduced heat release rates compared to PMMA and traditional silica-PMMA nanocomposites. 相似文献
75.
Shubhneet Kaur Parmjit S. Panesar Manab B. Bera Shweta Kumari 《International Journal of Food Properties》2013,16(5):1055-1066
Grain quality attribute tests based on physicochemical, textural, pasting, and in vitro digestion properties of eight different rice cultivars were studied. Basmati varieties showed higher values of amylose content, iodine absorption, blue value, hardness, cohesiveness, pasting temperature, and set back, whereas swelling power, solubility, adhesiveness, peak viscosity, and breakdown values were found to be higher in non-basmati varieties. The release of maltose from basmati rice flour (23.12–25.86 mg/g rice flour) was found to be slower as compared to non-basmati ones (27.43–28.36 mg/g rice flour). Amylose content showed significant correlations with different quality parameters at 5% level of significance. 相似文献
76.
Shweta K. Vyas 《纺织学会志》2013,104(2):191-199
Different varieties of silk differ from each other in their chemical composition as well as the physical, chemical and mechanical properties. Silk degumming is a primary important process, which needs to be carried out uniformly to a sufficient level to get good quality in further processes such as dyeing. In the present study, we have compared the efficiencies of five different degumming treatments for eri, tasar and mulberry silk fabrics using conventional, ultrasonic and microwave techniques. Among the various treatments, soda ash plus hydrogen peroxide and enzyme (papain) degumming recipies gave the best results in terms of weight loss and absorbency. As compared to the conventional technique, the treatments under ultrasonication and microwave enhanced the efficiency. The microwave technique was found to be superior, with the advantage of drastic reduction in treatment time, better retention of tensile strength and smooth appearance of silk. The dye uptake also increased after degumming. The molecular conformation of the different silk varieties, as estimated by FTIR spectroscopy, and the crystalline structure, as elucidated by X-ray diffraction, remained unchanged. SEM showed distinct morphological changes on degumming. 相似文献
77.
Crack free calcium modified PZT composite films have been synthesized using modified sol-gel process by depositing the slurries prepared by mixing powder of composition PbZr0.52Ti0.48O3 and sol of composition Pb(1−x)CaxZr0.52Ti0.48O3 (where x = 0, 0.06, 0.1) on Pt(1 1 1)/Ti/SiO2/Si substrate. The infilteration process has also been employed which resulted in dense microstructure of the films. Thickness of the films as measured by SEM of cross section of the films was more than 25 μm. The XRD patterns of the resultant films consisted of pure perovskite phase and no peak related to either pyrochlore phase or Pt substrate was observed. The room temperature dielectric constant and loss were compared. The temperature dependence of dielectric constant revealed that TC of all the films was same, i.e., 351 °C, in spite of different compositions of the sol used. Well saturated PE-loops of the films show that the films were ferroelectric in nature. 相似文献
78.
Response surface methodology (RSM) involving central composite design (CCD) was employed to optimize the concentrations of different media components for growth and Cr (VI) removal (100 mg l(-1) initial concentration) by Aspergillus lentulus AML05 at pH 6.5. The interaction between five variables i.e. glucose, K(2)HPO(4), MgSO(4), yeast extract, NH(4)NO(3) was studied and modelled. The statistical analysis of the results showed that in the range studied, yeast extract had a significant effect on Cr (VI) removal and production of fungal biomass. The optimum combination predicted via RSM was confirmed through experiment, whereby almost complete removal (99.8%) of Cr (VI) was obtained within 120 h. The validation of these results in terms of field applicability was also tested by treating industrial effluent supplemented with key media components. 相似文献
79.
Suryakumar Geetha Purushothaman Jayamurthy Karan Pal Shweta Pandey Ratan Kumar RC Sawhney 《Journal of the science of food and agriculture》2008,88(9):1592-1597
BACKGROUND: Liver injuries induced by carbon tetrachloride are the best‐characterized system of xenobiotic‐induced hepatotoxicity and commonly used model for the screening of hepatoprotective activities of drugs. The present study evaluates the hepatoprotective activity of sea buckthorn (Hippophae rhamnoides L.), family Elaeagnaceae, on carbon tetrachloride (CCl4)‐induced liver injury in male albino rats. The study was performed on Sprague–Dawley male albino rats weighing about 180–200 g. The animals were pretreated with three different doses of leaf extract (50, 100 and 200 mg kg?1 body weight) for 5 days. Hepatotoxicity was induced by single oral administration of 1.5 mL CCl4 kg?1 body weight on the fifth day. The animals were then sacrificed and assessed for various biochemical parameters. RESULTS: Administration of CCl4 significantly enhanced glutamate oxaloacetate transferase (GOT), glutamate pyruvate transferase (GPT), alkaline phosphatase (ALP) and bilirubin, and decreased total protein levels in the serum. Treatment with CCl4 also significantly decreased reduced glutathione (GSH), and decreased glutathione peroxidase and superoxide dismutase activity. CCl4 treatment also caused a significant increase in hepatic lipid peroxidation as assessed by malondialdehyde (MDA) levels in the tissue. Pretreatment of leaf extract at a concentration of 100 and 200 mg kg?1 body weight significantly (P < 0.05) protected the animals from CCl4‐induced liver injury. The extract significantly restricted the CCl4‐induced increase of GOT, GPT, ALP and bilirubin and better maintained protein levels in the serum. Further, it also enhanced GSH and decreased MDA levels. CONCLUSION: The results show that sea buckthorn leaf extract has significant hepatoprotective effects which might be due to its antioxidant activity and can be developed as a nutraceutical or food supplement against liver diseases. Copyright © 2008 Society of Chemical Industry 相似文献
80.
The Internet connects hundreds of millions of computers across the world running on multiple hardware and software platforms
providing communication and commercial services. However, this interconnectivity among computers also enables malicious users
to misuse resources and mount Internet attacks. The continuously growing Internet attacks pose severe challenges to develop
a flexible, adaptive security oriented methods. Intrusion detection system (IDS) is one of most important component being
used to detect the Internet attacks. In literature, different techniques from various disciplines have been utilized to develop
efficient IDS. Artificial intelligence (AI) based techniques plays prominent role in development of IDS and has many benefits
over other techniques. However, there is no comprehensive review of AI based techniques to examine and understand the current
status of these techniques to solve the intrusion detection problems. In this paper, various AI based techniques have been
reviewed focusing on development of IDS. Related studies have been compared by their source of audit data, processing criteria,
technique used, dataset, classifier design, feature reduction technique employed and other experimental environment setup.
Benefits and limitations of AI based techniques have been discussed. The paper will help the better understanding of different
directions in which research has been done in the field of IDS. The findings of this paper provide useful insights into literature
and are beneficial for those who are interested in applications of AI based techniques to IDS and related fields. The review
also provides the future directions of the research in this area. 相似文献