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21.
Mohamed N. Aboul-Enein Aida A. El-Azzouny Mohamed I. Attia Yousreya A. Maklad Mona E. Aboutabl Fatma Ragab Walaa H. A. Abd El-Hamid 《International journal of molecular sciences》2014,15(9):16911-16935
Synthesis and anticonvulsant potential of certain new 6-aryl-9-substituted-6,9-diazaspiro[4.5]decane-8,10-diones (6a–l) and 1-aryl-4-substituted-1,4-diazaspiro[5.5]undecane-3,5-diones (6m–x) are reported. The intermediates 1-[(aryl)(cyanomethyl)amino]cycloalkanecarboxamides (3a–f) were prepared via adopting Strecker synthesis on the proper cycloalkanone followed by partial hydrolysis of the obtained nitrile functionality and subsequent N-cyanomethylation. Compounds 3a–f were subjected to complete nitrile hydrolysis to give the respective carboxylic acid derivatives 4a–f which were cyclized under mild conditions to give the spiro compounds 5a–f. Ultimately, compounds 5a–f were alkylated or aralkylated to give the target compounds 6a–i and 6m–u. On the other hand, compounds 6j–l and 6v–x were synthesized from the intermediates 5a–f through alkylation, dehydration and finally tetrazole ring formation. Anticonvulsant screening of the target compounds 6a–x revealed that compound 6g showed an ED50 of 0.0043 mmol/kg in the scPTZ screen, being about 14 and 214 fold more potent than the reference drugs, Phenobarbital (ED50 = 0.06 mmol/kg) and Ethosuximide (ED50 = 0.92 mmol/kg), respectively. Compound 6e exhibited an ED50 of 0.019 mmol/kg, being about 1.8 fold more potent than that of the reference drug, Diphenylhydantoin (ED50 = 0.034 mmol/kg) in the MES screen. Interestingly, all the test compounds 6a–x did not show any minimal motor impairment at the maximum administered dose in the neurotoxicity screen. 相似文献
22.
Sibel Duman Bülent Kaya Fatma Caf Barış Enez Sema Aguloğlu Fincan 《International Journal of Hydrogen Energy》2021,46(29):15410-15430
For the first time in this innovative study, microorganisms such as Bacillus simplex bacteria, mostly used in biological activity studies, are used as a bio-supporter agent of iron to release hydrogen from sodium borohydride hydrolysis at 25.0 ± 0.1 °C. The goal is to investigate thoroughly sodium borohydride hydrolysis catalyzed by Fe2O3 nanoparticles impregnated on microorganism such as Bacillus simplex (BS) bacteria (Fe2O3@BS NPs) known with strong antibacterial properties, which makes innovative them a candidate for hydrolysis reaction. This study was focused on the preparation, identification, and catalytic use of biocatalyst-like Fe2O3@BS NPs for hydrogen release from the sodium borohydride hydrolysis at 25.0 ± 0.1 °C. The characterization results made after and before hydrolysis reaction using by SEM/SEM-EDX, FT-IR, XRD, UV–vis, XPS, DLS, ELS Zeta potential, ESR, and TEM techniques reveal the formation of highly active, stable, durable, and long-lived biocatalysts-like Fe2O3@BS NPs. 相似文献
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The 99m Tc-pyrimidine-4,5-diamine (99m Tc-PyDA) complex was prepared. The yield under the optimum conditions (5 mg of PyDA, pH 8, 25 μg of SnCl2·2H2O) was 96 ± 3%. The complex is stable in vitro for 24 h. The complex was tested on mice as potential marker for tumor hypoxia imaging. The complex showed high tumor hypoxia uptake with the target/nontarget (T/NT) ratio as high as ~3. 相似文献
25.
Investigating the effect of production process of ball mill refiner on some physical quality parameters of compound chocolate: response surface methodology approach
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Omer Said Toker Fatma Tugce Zorlucan Nevzat Konar Orhan Dağlıoğlu Osman Sagdic Dilek Şener 《International Journal of Food Science & Technology》2017,52(3):788-799
Chocolate compound was produced using ball mill refiner, and the effect of agitator shaft speed and refining time on the physical quality parameters (particle size, colour and steady‐state rheology) of compound chocolate was determined using response surface methodology. The shaft speed and refining time range were selected between 40–60 r.p.m. and 10–30 min, respectively. Determination coefficient of the models established for particle size, Newtonian viscosity and colour parameters (brightness, chroma and hue angle) were found to be very close to unity. Increasing shaft speed and time induced a reduction in particle size and an increase in viscosity of the samples. Temperature sweep test was also performed, and the obtained data were successfully fitted to Arrhenius equation to calculate the corresponding parameters representing temperature dependency of the compounds. The results highlighted that the establishment of such models can provide essential information in terms of optimisation of production processes regarding usage purpose of the compound chocolate. 相似文献
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Fathy A. Khalafalla Fatma H. M. Ali Abdel-Rahim H. A. Hassan Shady E. Basta 《Journal für Verbraucherschutz und Lebensmittelsicherheit》2016,11(2):137-143
In an attempt to determine the residual levels of lead (Pb), cadmium (Cd), mercury (Hg) and tin (Sn) in canned meat products marketed in Egypt, a total number of 160 random samples (40 each) of canned chicken luncheon (CCL), canned beef luncheon (CBL), canned frankfurter (CF) and canned corned beef (CCB) were randomly collected from different supermarkets in Egypt to be analyzed using atomic absorption spectrophotometry. From the obtained results, it was found that the mean values of residual levels of Pb in examined CCL, CBL, CF and CCB samples were 0.330, 0.224, 0.206 and 0.334 mg/kg, respectively, while those of Cd were 0.057, 0.053, 0.039 and 0.042 mg/kg, those of Hg were 0.387, 0.450, 0.402 and 0.332 mg/kg, and finally those of Sn were 2.061, 2.308, 0.755 and 1.997 mg/kg. The obtained results were compared with the permissible limits of heavy metals recommended by international and national authorities. In addition, the public health significance as well as the sources of contamination of canned meat products by heavy metals were addressed. 相似文献
29.
Fatma Ceyhun Şahin 《国际能源研究杂志》2017,41(4):526-539
There is no general rule in the literature to help choose a correct flow control device for any given case of turbomachinery applications. This suggests individual optimization of flow control devices for each specific case. The objective of this study is to prove experimentally the benefits of passive control methods in improving the compressor performance. This allows to reduce the fuel consumption, leading to energy saving and reduction of atmospheric pollution. Two features have been controlled in this study: flow separation over the blade surfaces and the secondary flow over the cascade endwalls. Vortex generator ribs are tested on the blade suction side for flow reattachment on the blade surfaces, and low‐profile vortex generators are tested on the side walls of the compressor cascade against secondary flow losses. Different vortex generator designs are compared for total pressure recovery, flow turning, boundary layer characteristics, and pressure distributions over the endwalls. Copyright © 2016 John Wiley & Sons, Ltd. 相似文献
30.
De La Torre Jessica Elizabeth Fatma Gassara Anne Patricia Kouassi Khaled Belkacemi 《Critical reviews in food science and nutrition》2017,57(6):1078-1088
Spices are parts of plants that due to their properties are used as colorants, preservatives, or medicine. The uses of spices have been known since long time, and the interest in the potential of spices is remarkable due to the chemical compounds contained in spices, such as phenylpropanoids, terpenes, flavonoids, and anthocyanins. Spices, such as cumin (cuminaldehyde), clove (eugenol), and cinnamon (cinnamaldehyde) among others, are known and studied for their antimicrobial and antioxidant properties due to their main chemical compounds. These spices have the potential to be used as preservatives in many foods namely in processed meat to replace chemical preservatives. Main chemical compounds in spices also confer other properties providing a variety of applications to spices, such as insecticidal, medicines, colorants, and natural flavoring. Spices provide beneficial effects, such as antioxidant activity levels that are comparable to regular chemical antioxidants used so they can be used as a natural alternative to synthetic preservatives. In this review, the main characteristics of spices will be described as well as their chemical properties, different applications of these spices, and the advantages and disadvantages of their use. 相似文献