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441.
In this paper, a new numerical method for solving fractional differential equations (FDEs) is presented. The method is based upon the fractional Taylor basis approximations. The operational matrix of the fractional integration for the fractional Taylor basis is introduced. This matrix is then utilized to reduce the solution of the fractional differential equations to a system of algebraic equations. Illustrative examples are included to demonstrate the validity and applicability of this technique.   相似文献   
442.
A novel biomimetic route for the synthesis of a water‐soluble poly(3,4‐ethylenedioxithiophene) (PEDT) in the presence of poly(styrene sulfonate) (PSS) and using iron(III)‐tetra(p‐sulfonatophenyl)porphyrin (FeIIITSPP), cobalt(III)‐tetra(p‐sulfonatophenyl)porphyrin (CoIIITSPP), manganese(III)‐tetra(p‐sulfonatophenyl)porphyrin (MnIIITSPP), and copper(II)‐tetra(p‐sulfonatophenyl)porphyrin (CuIITSPP) as effective catalysts is presented. The reactions were performed with different monomer, catalyst, template, and initiator concentrations. The absorbance of the polaron bands at various pH values indicated pH 2 as the best condition for polymerization. Precipitation or salting out was highly dependent on the mentioned factors. The formation of PEDT was confirmed by UV‐Vis and FT‐IR spectroscopy. Cyclic voltammetry proved the convenient electroactivity of the synthesized polymer. The presence of PSS that serves as a charge‐compensating dopant provides processability and water solubility and, in addition, a distinct advantage over similar reactions employing native enzymes due to higher stability and lower cost of the catalysts.  相似文献   
443.
A simple and convenient method has been used to prepare an SBA-Nicotinic acid (SBA-Niacin) composite on SBA-15 mesoporous silica as support. The composite was easily prepared by nucleophilic substitution of SBA-propylchloride with nicotinic acid. The structural properties of SBA-Niacin were systematically investigated by Fourier transform infrared spectroscopy, scanning electron microscopy, transmission and scanning electron microscopy, X-ray diffraction spectroscopy, thermal gravimetric analysis and Brunauer Emmett Teller. The catalytic activity of this nanocomposite was successfully tested through the one-pot synthesis of pyran annulated heterocyclic compounds via three-component couplings of aromatic aldehydes, malononitrile and β-diketone (dimedone and 4-hydroxy-6-methyl-2-pyrone) under solvent-free conditions.  相似文献   
444.
445.
Smart drug delivery systems have attracted a lot of attention as one of the new treatment methods for cancer. In this study, a smart drug delivery system carrying anticancer drugs was obtained by the intelligent synthesis of glucosamine (GA)-functionalized graphene oxide (GO)-based iron oxide nanoparticles (Fe3O4@GO-GA) using Hummers and chemical co-precipitation processes. Nanohybrids have a high surface area (280.26 m2/g) and superparamagnetic behaviour (Ms = 26.017 emu/g), indicating a significant loading capacity (373.78 mg/mg) and efficiency (96.3%) for pharmaceutical loading. An adsorption study of conventional daunorubicin (DNR) on this carrier showed that the drug release is more prone to occur under acidic conditions (pH = 5.5), at moderately high temperatures (T = 40°C), and in the absence of smart carriers. The toxicity of the smart nanohybrids was examined using the sulphorhodamine B (SRB) assay in Michigan Cancer Foundation-7 (MCF-7) cell lines. The rate of death of cells exposed to smart drug-containing systems in comparison to the systems without GA shows that GA reduces the toxicity of Fe3O4@GO.  相似文献   
446.

This study focused on developing a superparamagnetic graphene oxide-based nanocomposite consisting of iron oxide (IO) and gold nanoparticles for quercetin delivery. For this purpose, the structure and morphology of the designed nanocomposite (GO/IO/Au) were investigated by several characterization methods such as fourier-transform infrared (FT-IR) spectroscopy, X-ray diffraction (XRD) analysis, vibrating-sample magnetometer (VSM) analysis, field emission scanning electron microscopy (FESEM) and Transmission electron microscopy (TEM). Then, the biocompatibility of the synthesized nanocomposite was studied by Brine shrimp Artemia lethality assay, red blood cell hemolysis assay, and MTT (3-[4,5-dimethylthiazol-2-yl]-2,5 diphenyl tetrazolium bromide) assay. Moreover, the GO/IO/Au nanocomposite efficiency as an anticancer drug delivery system was evaluated in vitro conditions. The results showed that the designed nanocomposite is highly biocompatible and possesses a favorable magnetization (Ms?=?29.2 emu.g?1) making it a good candidate for biomedical applications. Also, it was confirmed that GO/IO/Au nanocomposite is a potent drug carrier that can effectively deliver quercetin to cancer cells.

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447.
448.
In this paper, a solid-state reaction route was developed to synthesize SrB6O10 crystalline powders. Regarding the last preparation methods, a short process time of synthesis was achieved that has not reported before. The prepared sample was characterized using various methods, such as X-ray diffraction, Raman spectroscopy, field emission scanning electron microscopy, transmission electron microscopy, and diffuse reflection spectroscopy. The obtained results proved that the prepared sample at temperature 840°C with 2.5 h duration consists of SrB6O10 crystalline powders with 4.96 eV bandgap.  相似文献   
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