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51.
In an attempt to improve tumor localization of docetaxel (DTX)‐loaded nanoparticles (NPs), zoledronic acid (ZOL) is used as a ligand to target bone metastasis. DTX‐loaded ZOL‐conjugated polyethylene glycol (PEG)ylated polybutyl cyanoacrylate (PBCA) NPs are prepared using an anionic polymerization technique. PBCA‐PEG‐ZOL NPs are subjected to cytotoxic assay in both BO2 and MCF‐7 cell lines. Cell cycle arrest and apoptosis induced by the PBCA‐PEG‐ZOL NPs are studied. Quantitative cellular uptake, NP uptake route characterization, confocal microscopy and IPP/ApppI levels are performed. PBCA‐PEG‐ZOL NPs show an enhanced cytotoxic effect in both BO2 as well as MCF‐7 cell lines due to higher uptake following ZOL‐mediated endocytosis. The molecular basis of apoptosis reveals the involvement of a cytoplasmic protein in activating the programmed cell death pathway. Route characterization studies reveal that PBCA‐PEG‐ZOL NPs uptake is not completely blocked even by using both inhibitors (genistein and phenyl arsinoxide) simultaneously, conferring that uptake is not entirely based upon clathrin or caveolae. PBCA‐PEG‐ZOL NPs showed 7 and 5.3 times increase in IPP and ApppI production, in comparison to ZOL treatment, and 138 times higher than the control group in MCF‐7 cell line. In BO2 cell line, after treatment with NPs, IPP was 5.35 times higher than ZOL solution. No ApppI in BO2 cell line after treatment with NPs and ZOL solution was found. NP distribution in tumor infected bone is also significantly high in comparison to the normal bone at any time point. It is concluded that ZOL‐conjugated NPs provide an efficient and targeted delivery of DTX, with synergistic effects. Thus, these NPs present a promising treatment in the near future, by actively targeting metastatic tumor.  相似文献   
52.
Multifunctional graphene oxide/reduced graphene oxide (GO/RGO) composites were prepared through electrostatic interaction using biocompatible ingredients. Different functionalities were added to GO/RGO by anchoring materials such as native lactoferrin (NLf), NLf protected Au clusters (designated as Au@NLf), chitosan (Ch) and combinations thereof. Anchoring of Ch and NLf enhances the antibacterial property of RGO/GO. The addition of Ch to RGO/GO not only helped in forming stable dispersions but also helped in fabricating large (cm(2)) area films through a simple solvent evaporation technique. Functionalities such as photoluminescence were added to Ch-RGO/GO composites by anchoring Au@NLf on it. The composites thus formed showed stable luminescence in presence of various metal ions in the solid state. The composite showed reasonable stability against pH and temperature variations as well. The as-prepared films were transparent and the transparency could be modulated by controlling the concentration of RGO/GO in the composite. The antibacterial property and ability to form stable thin films may provide an opportunity to use such composites for medical and environmental remediation applications as well. Erasable patterns were fabricated on the film by stamping required patterns under compressive pressure. Luminescent patterns can be inscribed on the film and can be erased by simply wetting it. Such films with erasable information may be useful for security applications.  相似文献   
53.
Number of diethanol amides has been developed by scientist using various vegetable oils and not from neem seed oil. Most of the research work on neem seed oil has explored its applications in pharmaceutical and pesticides fields. This paper representing new area of application of neem seed oil for polymeric resin, in which we attempted to synthesize the neem seed oil based poly(urethane fatty amides) by reaction of neem oil fatty amide (AIJFA) with trimer of isophorone diisocyanate (IPDI). Spectral study of AIJFA was carried out by using FT-IR and 1H NMR techniques. Molecular weight of AIJFA was determined by gel permeation chromatography (GPC). Fatty acid composition of neem seed oil was obtained by gas chromatographic method. The coatings applied on mild steel plates were evaluated by determining coating properties, chemical and corrosion resistances. TGA study of coatings showed higher thermal stability to AIJFA based PU coatings compared to normal urethane and alkyd coatings.  相似文献   
54.
Grain refinement of bulk metals using severe plastic deformation (SPD) is a popular approach to improve both strength and toughness. In this paper, grain refinement of steel processed by warm multiaxial forging (MAF) and its mechanical behavior has been investigated. Coarse-grained, plain low carbon steel was deformed using MAF at 500 °C. Microstructural evolution is characterized using electron backscattered diffraction and mechanical behavior has been studied. Fraction of low angle grain boundaries (LAB) is observed to increase with strain up to total engineering strain of 1.3 thereafter it starts decreasing whereas, high angle grain boundaries showed just the opposite trend. It appears that initially grain subdivision takes place with imposition of strain thereby increasing the fraction of LAB. After a critical strain these LAB transforms into the high angle boundaries (HAB). The initial coarser grains of average 30 μm size subdivided into grains of the size finer than 0.5 μm. This has been confirmed by TEM micrographs. Improved tensile strengths and hardness values are obtained after warm MAF.  相似文献   
55.
An amorphous iron nitride thin film was deposited using reactive ion beam sputtering of iron by a beam of argon and nitrogen ions. Nitrogen content in the film as determined from conversion electron Mössbauer spectroscopy (CEMS) and X-ray photoelectron spectroscopy (XPS) was FeN0.7. The mass density of the film was calculated using energy-dispersive X-ray reflectivity (EDXRR) measurements and is found to be 6.0 gm/cm3. CEMS shows that the film is nonmagnetic in nature. Morphology of the film is obtained from atomic force microscopy (AFM). The surface roughness of the film does not increase appreciably beyond that of the substrate even after a deposition of 131 nm of material with these qualities the film is a good candidate for the multilayer superstructure of a nuclear Bragg monochromator of the type 56FeN0.7/57FeN0.7.  相似文献   
56.
The behavior of superconducting transition temperature TC in superconducting/ferromagnetic (S/F) multilayers as a function of different layer thicknesses and for varying magnetic moment μB of the F layer atoms is studied. Multilayer structures consist of five bilayers of constant superconducting Nb layer thickness of 400 Å and Fe of 6 and 24 Å each. The analysis of the magnetization data revealed that for tFe=6 Å, the Fe layer is non-magnetic. The interpretation of the observed TC behavior is attributed to the change of the interaction of the cooper pairs with this layer at the onset of ferromagnetism for tFe=6 Å. The hysteresis curve recorded under isothermal conditions at 4.5 K for [Nb (400 Å)/Fe (6 Å)]5 multilayers shows the usual MH hysteresis behavior which is typical of a hard type-II superconductor exhibiting an irreversibility field Hirr of 3.5 kOe with substantial pinning at lower field. In addition, [Nb(400 Å)/Fe(6 Å)]5 multilayer displays anomalous behavior in the form of paramagnetic peak in the superconducting state just below the transition temperature TC=6.25 K.  相似文献   
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59.
Kinetics of hydration of propylene oxide using an ion-exchange resin catalyst in a slurry reactor was studied. The kinetics of homogeneous, uncatalyzed reaction was studied separately and used to obtain heterogeneous reaction kinetics. The homogeneous reaction was found to be 0.43 order with respect to propylene oxide concentration. The heterogeneous reaction was found to have intraparticle diffusional resistance under certain conditions. The intrinsic kinetic parameters and effective diffusivity were obtained from these data. The heterogeneous reaction was found to be 0.55 order with respect to propylene oxide concentration. The activation energies obtained for homogeneous and heterogeneous reactions were 51.5 and 53.4 kJ/mol, respectively. A theoretical model incorporating all the mass transfer resistances has been proposed.  相似文献   
60.
In this paper a comprehensive review is presented of risk assessment techniques adopted in the mining industry worldwide;those techniques applied in other hazardous industries and potential techniques which are robust,mature and holistic and can be implemented for the Indian mining industry in future to enhance workplace safety are also presented.Findings from the review are indicative of the fact that socio-technical complexity of industrial systems has increased.Recent developments in the area of risk management highlight the need for implementation of the latest robust techniques of risk assessment in the mining sector.In consideration of the present scenario,the development of a model for risk analysis having an interface between hazard identification and risk assessment,along with an interface between risk assessment and accident causation to predict if an accident will occur under given conditions,has become dire necessity.This will increase hazard awareness and enable mine management to select and prioritize problem areas and identify safety system weaknesses in both underground and surface mining.This will ultimately help decision makers,risk analysts and safety managers make a major contribution in the development of workplace safety with a near-to-zero accident rate.  相似文献   
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