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1.
Pain management during dental procedures is a cornerstone for successful daily practice. In current practice, the traditional needle and syringe injection is used to administer local anesthesia. However, the appearance of long needles and the pain associated with it often leads to dental anxiety deterring timely interventions. Microneedles (MNs) have emerged as a minimally invasive alternative to hypodermic needles and shown to be effective in transdermal drug delivery applications. In this article, the potential use of MNs for local anesthesia delivery in dentistry is explored. The development of a novel conductive MN array that can be used in combination with iontophoresis technique to achieve drug penetration through the oral mucosa and the underlying bone tissue is presented. The conductive MN array plays a dual-role, creating micro-conduits and lowering the resistance of the oral mucosa. The reduced tissue resistance further enhances the application of a low-voltage current that is able to direct and accelerate the drug molecules to target the sensory nerves supplying teeth. The successful delivery of lidocaine using this new strategy in a clinically relevant rabbit incisor model is shown to be as effective as the current gold standard.  相似文献   
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Multimedia Tools and Applications - Analysis of facial images decoding familial features has been attracting the attention of researchers to develop a computerized system interested in determining...  相似文献   
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Transmission of pathogenic microorganisms on textile in the hospital settings may contribute to nosocomial infection. This study was aimed to develop a natural antimicrobial finishing on textile that can prevent transmission of pathogenic microorganisms that meets American Association of Textiles Chemists and Colorists (AATCC) standard. Punica granatum L ethanolic extract was shown to have broad spectrum antimicrobial efficacy with bis(6-methylheptyl)-benzene-1,2-dicarboxylate and ethyl-pentadecanoate as the main bioactive constituents. Textile samples developed with the extract finishing exhibited excellent antimicrobial efficacy with a growth reduction of 99.9% on Hoheinstein Challenge Test. The wash durability of the finished textile was found good even after 30 washes with commercial detergent.  相似文献   
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Clean Technologies and Environmental Policy - Use of by-product materials, such as steel slag and cathode ray tube glass, as alternative recycled materials in the construction of roads, could...  相似文献   
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A conventional free‐radical initiating process was used to prepare graft copolymers from acrylonitrile (AN) with corn‐cob cellulose with ceric ammonium nitrate (CAN) as an initiator. The optimum grafting was achieved with corn‐cob cellulose (anhydroglucose unit, AGU), mineral acid (H2SO4), CAN, and AN at concentrations of 0.133, 0.081, 0.0145, and 1.056 mol/L, respectively. Furthermore, the nitrile functional groups of the grafted copolymers were converted to amidoxime ligands with hydroxylamine under basic conditions of pH 11 with 4 h of stirring at 70°C. The purified acrylic polymer‐grafted cellulose and polyamidoxime ligand were characterized by Fourier transform infrared spectroscopy and field emission scanning electron microscopy analysis. The ligand showed an excellent copper binding capacity (4.14 mmol/g) with a faster rate of adsorption (average exchange rate = 7 min), and it showed a good adsorption capacity for other metal ions as well. The metal‐ion adsorption capacities of the ligand were pH‐dependent in the following order: Cu2+ > Co2+ > Mn2+ > Cr3+ > Fe3+ > Zn2+ > Ni2+. The metal‐ion removal efficiency was very high; up to 99% was removed from the aqueous media at a low concentration. These new polymeric chelating ligands could be used to remove aforementioned toxic metal ions from industrial wastewater. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014 , 131, 40833.  相似文献   
8.
We report on the morphology evolution during heating and melting of lamellar poly(isoprene)-block-poly(ferrocenyldimethylsilane) (PI76-b-PFDMS76) raft crystals deposited at the native oxide surface of silicon (SiO2) or at a highly ordered pyrolytic graphite (HOPG) surface, studied by in situ temperature controlled atomic force microscopy. Crystals deposited on hydrophilic SiO2 surfaces revealed an irreversible decrease in length at temperatures of up to tens of degrees above their expected melting temperature, while maintaining their platelet-like structure. Crystals deposited on hydrophobic HOPG surfaces initially decreased in length below their expected melting temperature, while at 120 °C and above a typical molten morphology was observed. In addition, the irreversible formation of a PI76-b-PFDMS76 wetting layer around the crystals was observed upon increasing the temperature. These observations in the morphological behavior upon heating emphasize the role of interfacial energy between a surface deposited block copolymer based macromolecular nanostructure and its supporting substrate.  相似文献   
9.
Boron nitride microtubes are synthesized in a dual zone quartz tube furnace at 1200°C with ammonia as a reaction atmosphere. Field emission scanning electron microscopy (FE-SEM) results show a unique cone-like morphology of the tubes with larger internal space and thin walls structure. The diameters of the tubes were found to be in the range of 1 to ~2 µm with the walls thickness estimated to be from 10 to 100 nm. XPS survey shows N 1 s and B 1 s peaks at 398.7 and 191 eV, respectively, that represent h-BN in the sample. Raman spectroscopy indicates a high-intensity peak at 1372.53 (cm?1) that corresponds to the E2g mode of h-BN. Along with the novel tubular morphology of boron nitride microtubes, the present work also explains a mechanism for the formation of boron nitride nanosheets (from boron nitride microtubes) found in the FE-SEM results of the current sample.  相似文献   
10.
A tunable, passively Q-switched thulium doped fluoride fibre (TDFF) laser using a reduced-graphene oxide-silver (rGO-Ag) thin film as a saturable absorber (SA) for S band operation is proposed and its efficacy demonstrated. Over a pump power range of 91.4?mW up to 158.6?mW, passively generated Q-switched pulses are observed with repetition rates from 20 to 34.5?kHz and pulse widths from 3.1 to 7.1?µs. The highest pulse energy observed is 101.2?nJ with a signal to noise ratio of ~42?dB. The proposed laser has a tuning range ~52?nm from 1458 to 1510?nm with a tunable bandpass filter (TBPF) introduced into the cavity.  相似文献   
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