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81.
Esfandyari-Manesh M Javanbakht M Dinarvand R Atyabi F 《Journal of materials science. Materials in medicine》2012,23(4):963-972
Water-compatible imprinted nanoparticles were prepared for carbamazepine as a template and used for the selective extraction and controlled release of carbamazepine. Assay materials and drug delivery carriers were typically used in aqueous environments, so it is generally preferable to prepare solvent-free molecularly imprinted nanoparticles in water using the miniemulsion polymerization method. The present work investigates a bio-analytical strategy generically applicable to imprinted materials for molecular recognition studies, including equilibrium and non-equilibrium binding, and release experiments, increasing the knowledge of the molecular interactions between the template molecules and imprinted nanoparticles. The results showed that the imprinted nanoparticles exhibited a higher binding level and slower release rate than non-imprinted nanoparticles. The selectivity of imprinted nanoparticles for carbamazepine studied in comparison with an analogue compound, oxcarbazepine, the main metabolite of carbamazepine. The recovery and selectivity of carbamazepine in human serum was determined to be 100%, 1.7 times that of oxcarbazepine. The results indicated that carbamazepine-imprinted nanoparticles are appropriate for serum level determination of the drug in therapeutic range. The template to functional monomer ratio as a key factor controlling the recognition and release kinetic mechanism of imprinted nanoparticles is discussed. The imprinted nanoparticles prepared at the appropriate template to functional monomer mole ratio (2:8) exhibited the best drug affinity (5.1 times higher) and a slower drug release rate due to the interaction of carbamazepine with the imprinted cavities within the nanoparticles. Loaded imprinted nanoparticles as drug reservoirs were able to prolong carbamazepine release, in 1% wt sodium dodecyl sulfate aqueous solution, for more than 8 days. 相似文献
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A rate‐based mathematical model was developed for the reactive absorption of H2S in NaOH, with NaOCl or H2O2 as the chemical oxidant solutions in a packed column. A modified mass transfer coefficient in the gas phase was obtained by genetic algorithm and implemented in the model to correct the assumption of instantaneous reactions. The effects of different operating variables including the inlet H2S concentration, inlet gas mass flux, initial NaOH, concentrations of the chemical oxidants in the scrubbing solutions, and liquid‐to‐gas ratio on the H2S removal efficiency were studied. A genetic algorithm was employed to optimize the operating variables in order to obtain maximum removal efficiency of H2S. The model results were in good agreement with the experimental data. 相似文献
84.
A novel bilayer nanofibrous wound dressing, with enhanced mechanical properties is successfully fabricated. This membrane, consisted of polyvinylidenefluoride (PVDF) nanofibers for providing tensile strength and polyhydroxybutyrate/chitosan (PHB/CTS) nanofibers loaded with gentamicin with ability of controlled drug delivery, is a great choice for post-surgical ulcers. Mechanical properties showed dramatically improvement of tensile strength by addition of PVDF layer. Gentamycin release represented both an immediate and a sustained release of about 24?h and 1 week, respectively and release increment with increase of CTS ratio. Results also revealed that drug release in structures follow first order kinetic and Fickian release mechanism. 相似文献
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H2S Reactive Absorption from Off‐Gas in a Spray Column: Insights from Experiments and Modeling 下载免费PDF全文
H2S removal from an off‐gas stream was performed in a spray column by H2S reactive absorption into a NaOH solution. The individual and interactive effects of three independent operating variables on the percentage of absorbed H2S were investigated: the initial pH of the scrubbing solution, the initial scrubbing solution temperature, and the volumetric liquid‐to‐gas ratio. The optimum operating variables were determined by response surface methodology (RSM) attaining a percentage of absorbed H2S of 98.7 ± 0.2 %. Additionally, the process performance was modeled by an artificial neural network (ANN) to predict the percentage of absorbed H2S. The results showed that the experimental data agreed better with the ANN model than with the RSM results. 相似文献
88.
Fatemeh Haghighat 《Polymer-Plastics Technology and Engineering》2017,56(7):794-803
Polyvinylpyrrolidone/hydroxyl-functionalized multiwalled carbon nanotube and sulfonyl-functionalized multiwalled carbon nanotube nanocomposites were prepared in aqueous media. The structure, morphology, and thermal characterization of the prepared nanocomposites were done by Fourier transform infrared, scanning electron microscopy, thermogravimetric analysis, and differential scanning calorimetry techniques. The polyvinylpyrrolidone/hydroxyl-functionalized multiwalled carbon nanotube and polyvinylpyrrolidone/sulfonyl-functionalized multiwalled carbon nanotube nanocomposites improved the thermal properties of polyvinylpyrrolidone. According to the differential scanning calorimetry analysis, the glass transition temperature of 101.6 and 84.6°C is observed for the polyvinylpyrrolidone/hydroxyl-functionalized multiwalled carbon nanotube (5% w/w) and polyvinylpyrrolidone/sulfonyl-functionalized multiwalled carbon nanotube (5% w/w) nanocomposites, respectively. The energy-dispersive X-ray spectroscopy image of polyvinylpyrrolidone/sulfonyl-functionalized multiwalled carbon nanotube (5% w/w) nanocomposite showed a homogenous distribution of sulfonyl-functionalized multiwalled carbon nanotube in the polyvinylpyrrolidone matrix. 相似文献
89.
Abdol-Samad Abedi Fatemeh Hemmati Amir Hossein Abedini Abdorreza Mohammadi Masoumeh Moslemi 《Journal of the American Oil Chemists' Society》2021,98(10):969-978
A simple, fast, and reliable liquid–liquid micro-extraction (LLME) method assisted by thermal ultrasound approach was developed for simultaneous determination of synthetic phenolic antioxidants (SPAs) in edible oils by high-performance liquid chromatography equipped with ultraviolet detector (HPLC-UV). The synthetic antioxidants were propyl gallate (PG), butylated hydroxyanisole (BHA), tert-butylhydroquinone (TBHQ), and butylated hydroxyltoluene (BHT). The best extraction conditions were observed were methanol/acetonitrile (1:1, v/v) as the solvent, ultrasound at 4 min, and a temperature of 40°C. The linearity of the calibration curves for the optimum conditions were R2 > 0.989 for all of the SPAs in a range from 1–200 μg ml−1. Relative standard deviation (RSD %) for five analysis was in range of 2.83% to 4.21%. Limit of detection (LOD) and limit of quantification (LOQ) were obtained in range of 0.012–0.06 and 0.04–0.2 μg g−1, respectively. With regard to recovery, a range of 91%–116% was calculated for the spiked edible oils. 相似文献
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