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91.
弱激光血管内照射积累效应的实验研究   总被引:1,自引:0,他引:1  
大量实验证明:激光血管内照射能改善机体的许多生理生化指标。本实验主要研究He-Ne激光和半导体绿激光对T淋巴细胞非特异性酯酶和红细胞乳酸氢酶的积累效应及差异,结果表明:差异显著,这为两种激光的临床应用提供重要参考。  相似文献   
92.
In this paper, a new concept of enzyme inhibition-based biosensor involving a two enzyme system was developed. The latter displays a signal increase instead of a decrease in the presence of an inhibitor. HRP and catalase were thus separately entrapped into Layered Double Hydroxides (LDH), an anionic clay, as a host matrix. The inner layer was constituted of HRP electrically wired by [Zn2CrABTS] LDH and the outer layer contained catalase immobilized in [Zn3AlCl] LDH. Both enzymes catalyzed the decomposition of H2O2, HRP its reduction and catalase its breakdown into oxygen and water. Nitrite was selected as a specific inhibitor of catalase. In the presence of H2O2, the nitrite addition blocked the H2O2 consumption by catalase, inducing thus an increase in the amperometric signal of the H2O2 reduction at 0 V by the wired HRP. The optimum configuration of the bi-enzyme biosensor displayed in aerated aqueous solutions, a nitrite sensitivity of 102 μA M− 1· cm− 2 with a fast response time, the detective limit being 4 μM.  相似文献   
93.
In this study, 5‐sulfosalicylic acid (SA) anions have been intercalated into Mg3Al‐NO3 layered double hydroxide (LDH) to synthesize SA‐intercalated Mg3Al‐NO3LDH (LDH‐SA) by ion‐exchange reaction. Then, the effects of LDH, SA, and LDH‐SA on the photostability of wood flour/polypropylene (WF/PP) composites during accelerated ultraviolet (UV) weathering were investigated. The surface color, surface gloss, and mechanical properties of the composites during weathering were tested, accompanied by characterizations using SEM, ATR‐FTIR, and TG. The results showed that (1) SA anions completely replaced the anions in LDH and the thermal stability of LDH‐SA was considerably enhanced; (2) composites with LDH or LDH‐SA exhibited less color change, fewer surface cracks, better thermal stability, and less losses of mechanical properties than the control group; (3) LDH‐SA showed a long‐term efficiency and alleviated the photo‐oxidation of WF/PP composites successfully; (4) LDH‐SA blocked UV light by physical shield effect of the layer sheets, as well as the chemical absorbability of the interlayer anions. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017 , 134, 44597.  相似文献   
94.
A novel hierarchical nanotube array (NTA) with a massive layered top and discretely separated nanotubes in a core–shell structure, that is, nickel–cobalt metallic core and nickel–cobalt layered double hydroxide shell (Ni? Co@Ni? Co LDH), is grown on carbon fiber cloth (CFC) by template‐assisted electrodeposition for high‐performance supercapacitor application. The synthesized Ni? Co@Ni? Co LDH NTAs/CFC shows high capacitance of 2200 F g?1 at a current density of 5 A g?1, while 98.8% of its initial capacitance is retained after 5000 cycles. When the current density is increased from 1 to 20 A g?1, the capacitance loss is less than 20%, demonstrating excellent rate capability. A highly flexible all‐solid‐state battery‐type supercapacitor is successfully fabricated with Ni? Co LDH NTAs/CFC as the positive electrode and electrospun carbon fibers/CFC as the negative electrode, showing a maximum specific capacitance of 319 F g?1, a high energy density of 100 W h kg?1 at 1.5 kW kg?1, and good cycling stability (98.6% after 3000 cycles). These fascinating electrochemical properties are resulted from the novel structure of electrode materials and synergistic contributions from the two electrodes, showing great potential for energy storage applications.  相似文献   
95.
Supercapacitors (SCs) have been widely studied as a class of promising energy‐storage systems for powering next‐generation E‐vehicles and wearable electronics. Fabricating hybrid‐types of electrode materials and designing smart nanoarchitectures are effective approaches to developing high‐performance SCs. Herein, first, a Ni‐Co selenide material (Ni,Co)Se2 with special cactus‐like structure as the core, to scaffold the NiCo‐layered double hydroxides (LDHs) shell, is designed and fabricated. The cactus‐like structural (Ni,Co)Se2 core, as a highly conductive and robust support, promotes the electron transport as well as hinders the agglomeration of LDHs. The synergistic contributions from the two types of active materials together with the superior properties of the cactus‐like nanostructure enable the (Ni,Co)Se2/NiCo‐LDH hybrid electrode to exhibit a high capacity of ≈170 mA h g?1 (≈1224 F g?1), good rate performance, and long durability. The as‐assembled (Ni,Co)Se2/NiCo‐LDH//PC (porous carbon) asymmetric supercapacitor (ASC) with an operating voltage of 1.65 V delivers a high energy density of 39 W h kg?1 at a power density of 1650 W kg?1. Therefore, the cactus‐like core/shell structure offers an effective pathway to engineer advanced electrodes. The assembled flexible ASC is demonstrated to effectively power electronic devices.  相似文献   
96.
Based on the electrochemical mechanism of Faraday supercapacitors (FSs), we design a microstructure configuration of electrode materials (EMs) in this work, aiming to promote the electrochemical performance of FSs. This configuration of EMs has two dimensional sheets-crosslinked network with narrow mesopore size distribution. It is reasonable to believe that the configuration is in favor of the electrochemical performance of EMs to the greatest extent. We try to build this structure configure using Ni-Co layered double hydroxide (LDH) nanosheets as building blocks by a facile sol-gel approach. Due to the Co2+ ions, we realize this structure configuration consisting of Ni-Co LDH nanosheets. Benefiting from the advantages of this configuration, the Ni-Co LDH presents high electrochemical performance. It has high specific capacity of 1170 C g?1 at low current density of 2.0 A g?1, and 500 C g?1 at high current density of 39.6 A g?1. The asymmetric supercapacitors of Ni-Co LDH exhibit high energy density of 74.37 Wh kg?1 at low power density of 492 Wh kg?1 and keep relatively high energy density of 15.99 Wh kg?1 at high power density of 6395 Wh kg?1. These results suggest that the designed structure configuration of EMs is rational for application in FSs.  相似文献   
97.
Water electrolysis is one of the important methods for hydrogen production, but the oxygen evolution reaction (OER) on the anode has a higher theoretical potential. Using urea oxidation reaction (UOR) instead of OER has been an energy-saving method because it has a lower theoretical potential and also can reduce pollution. In this paper, NiCoZn LDH/NF, P–NiCoZn LDH/NF-X (X is the atom ratio of P) = 10%, 15%, 20%) were synthesized through typically hydrothermal and calcination methods. P–NiCoZn LDH/NF-15% was demonstrated to be abifunctional electrocatalyst towards HER and UOR. When P–NiCoZn LDH/NF-15% is used as the anode and cathode for urea-water electrolysis,it shows that when the current density is 100 mA cm?2, the voltage is 1.479 V for urea-water electrolysis, which is much better than that of IrO2/NF||Pt/C/NF (1.698 V). Thus, P–NiCoZn LDH/NF-15% is expected to replace precious metals for practical applications.  相似文献   
98.
Mg‐Al layered double hydroxide (LDH) nanohybrids intercalated with ibuprofen (IBU) with particle sizes of 150–530 nm have been synthesized through hydrothermal and coprecipitation treatment in aqueous solution without any organic solvent. The in vitro drug release properties of as‐prepared IBU‐LDH nanohybrids are systematically studied and the kinetic simulation to the release profiles suggests that the release processes of the larger nanohybrids are mainly controlled by intraparticle diffusion. The morphology changes from thick sheet‐like into thin margin‐curved platelets for the larger nanohybrid particles, induced by the hydrophobic IBU anions aggregations located in the edge region of interlayer via ion‐exchange diffusion process, is firstly observed during the release process. Based on the SEM, HRTEM, XRD, FTIR, and UV‐vis analyses of the samples recovered at different release time, a release mechanism model of the as‐prepared IBU‐LDH nanohybrids is tentatively proposed along with their morphology changes during the whole release process. © 2010 American Institute of Chemical Engineers AIChE J, 2011  相似文献   
99.
The thermal decomposition behavior of NiFe layered double hydroxide (LDH) was investigated by thermogravimetric analysis-differential scanning calorimetry (TG-DSC). The calcined product at 500 °C was mainly NiO/FeOx composite oxide, of which FeOx was amorphous oxide; the calcined product at 650 °C was mainly NiO/NiFe2O4 composite oxide. The polarization curves and chronopotentiometry stated that the NiO/FeOx and NiO/NiFe2O4 showed good electrocatalytic OER and ORR activity; the OER activity of NiO/FeOx was better than that of NiO/NiFe2O4; the ORR activity of NiO/NiFe2O4 was better than that of NiO/FeOx.  相似文献   
100.
ABSTRACT: Bog bilberry (Vaccinium uliginosum L.) is a blue-pigmented edible berry related to bilberry (Vaccinium myrtillus L.) and the common blueberry (Vaccinium corymbosum). The objective of this study was to investigate the effect of a bog bilberry anthocyanin extract (BBAE) on cell growth, membrane permeability, and cell cycle of 2 malignant cancer cell lines, Caco-2 and Hep-G2, and a nonmalignant murine 3T3-L1 cell line. BBAE contained 3 identified anthocyanins. The most abundant anthocyanin was cyanidin-3-glucoside (140.9 ± 2.6 μg/mg of dry weight), followed by malvidin-3-glucoside (10.3 ± 0.3 μg/mg) and malvidin-3-galactoside (8.1 ± 0.4 μg/mg). Hep-G2 LC50 was calculated to be 0.563 ± 0.04 mg/mL, Caco-2 LC50 was 0.390 ± 0.30 mg/mL and 0.214 ± 0.02 mg/mL for 3T3-L1 cells. LDH release, a marker of membrane permeability, was significantly increased in Hep-G2 cells and Caco-2 cells after 48 and 72 h compared to 24 h. The increase was 21% at 48 h and 57% at 72 h in Caco-2 cells and 66% and 139% in Hep-G2 cells compared to 24 h. However, 3T3-L1 cells showed an unexpected significant lower LDH activity (P ≤ 0.05) after 72 h of exposure corresponding to a 21% reduction in LDH release. BBAE treatment increased sub-G1 in all 3 cell lines without influencing cells in the G2/M phase. BBAE treatment reduced the growth and increased the accumulation of sub-G1 cells in 2 malignant and 1 nonmalignant cell line; however, the effect on membrane permeability differs considerably between the malignant and nonmalignant cells and may in part be due to differences in cellular membrane composition.  相似文献   
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