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91.
Food Science and Biotechnology - In our previous study, black raspberry (BR) reduced the serum levels of trimethylamine-N-oxide and cholesterol in rats fed excessive choline with a...  相似文献   
92.
Zhang Z  Zhu J  Park KJ 《Water research》2006,40(1):162-174
A bench-scale study on swine manure stabilization for odour control was conducted using batch aeration reactors. In trial 1, two aeration lengths, i.e., 0.5 and 4.0 day, were used under uncontrolled ambient temperature that increased gradually over the experimental period. While in trial 2, a 16.0-day aeration scheme was employed under constant 17 degrees C. An airflow rate of 1.2L/s/m(3) was used for both trials to aerate batch reactors containing finishing pig manure with initial total solids (TS) levels ranging from 0.5 to 4.0%. Manure stabilization during the 90-day post-treatment storage was evaluated by the changes in organic materials, nitrogen and volatile fatty acids (VFA). The odour generation potential in the treated manure was determined by the changes in VFA. Up to 827 mL of liquid was lost due to aeration related foaming. The reductions in total volatile solids (TVS), 5-day biochemical oxygen demand (BOD(5)), total Kjeldahl nitrogen (TKN) and VFA during storage were improved when aeration length increased. Low solids levels offered a more advantageous circumstance for manure stabilization and odour control. Biodegradation of organic matter, removal of nitrogen, and breakdown of VFA would increase with increasing ambient temperature. VFA removals in manure under 16.0-day aeration were higher than those under 0.5- and 4.0-day aeration; however, VFA regeneration started to exceed its consumption on day 20 (4 days after the aeration treatment). BOD(5) was the best estimate of VFA concentration in the aerated manure during storage. The 4.0-day aeration scheme was sufficient to stabilize manure to effectively assuage odour generation potential during the 90-day storage under increasing ambient temperature conditions.  相似文献   
93.
94.
Direct covalent attachment of amorphous and semicrystalline polyetherketones onto the surface of either an as-received multi-walled carbon nanotube (MWNT) or a vapor-grown carbon nanofiber (VGCNF) in polyphosphoric acid (PPA) with optimized P2O5 content resulted in uniform grafting of polyetherketones to these carbon nanoscale materials. Soxhlet extraction experiment, the spectra from FT-IR spectroscopy and the clear images from high-resolution transmission electron microscopy showed that the covalent attachment is effective in uniformly coating the PEK grafts on the surfaces of both MWNT and VGCNF. Additionally, a drastic increase in solution viscosity due to the formation of giant molecules was monitored during polymerization. As such, the resulting nanocomposites were easily fabricated via a simple compression molding technique. The alignment possibility of MWNT and VGCNF grafted with semicrystalline PEK in these thermoplastic nanocomposites via solution fiber spinning was also demonstrated.  相似文献   
95.
ARelative contributions of lower extremity joints on the support moment were investigated in this study Three-dimensional gait analyses were performed in normal walking and in unexpected step-down walking For both gait studies, inverse dynamics were performed to obtain each joint moment of the lower extremity, which was applied to the forward dynamics simulation to determine the contributions on the support moment at different phases of walking The forward dynamic simulation results showed that, in normal walking, the ankle plantar flexois contributed significantly during single-limb-support However, the ankle plantar flexors, knee extensois and hip extensors worked together duimg double-limb-support In unexpected step-down walking, the important contributors on the support of the body during single-limb-support were not only ankle plantar flexors but also knee extensors This study, analyzing the relative contributions of the lower limb joint moments for the body support, would be helpful to understand diffetent unexpected walking conditions and compensatory mechanisms for various pathological gaits  相似文献   
96.
For this study, several TiAl–Nb–Si-based alloys were designed for a ductility improvement, whereby the high-temperature strength and oxidation resistance were not sacrificed. The environmental properties under the cyclic oxidation behaviors of the TiAl alloys were evaluated at 900 °C for up to 360 cycles. The compositions of the as-cast alloys determined their microstructures, and the cyclic oxidation behavior of the selected alloy was relatively comparable to that of a commercial TiAl alloy that is currently used in automotive engines.  相似文献   
97.
The characteristic nanoscale dynamics of the alkyl side groups in the light-emitting polymer poly[2-methoxy-5-(2′-ethyl-hexyloxy)-1,4-phenylene vinylene] have been investigated using quasi-elastic neutron scattering (QENS). The measurements were taken below the polymer's glass transition (TTg ≃ 353 K), where the main backbone is in a rigid state and does not contribute to the broadening of the QENS signal. An analytical diffusion model consisting of a static term and two dynamical components, characterizing the flexible side groups, provide an excellent fit to the experimental data. The two observed dynamical processes are all localized in character, with no meaningful dependence on temperature. The faster process, with characteristic timescale of ∼18 ps at room temperature (RT), can be linked to the average mobility of the terminal protons of the alkyl chain, while the slower process, with characteristic timescale of ∼170 ps at RT, to those protons at the other end of the alkyl chain, closest to the backbone. While the fraction of mobile protons contributing to the QENS signal increases with increasing temperature, the characteristic timescale and confining volume within which the protons are able to move locally depend chiefly on the polymer conformational state. © 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019 , 136, 47394.  相似文献   
98.
The objective of this study was to evaluate the status of the markers related to inflammation in db/db mice fed black raspberry seed (BRS) oil, which is rich in α‐linolenic acid. Mice were divided into four groups: (1) C57BL/6 mice fed 16 % calories from soybean oil (normal CON); (2) C57BL/KsJ‐db/db mice fed 16 % calories from soybean oil (CON); (3) C57BL/KsJ‐db/db mice fed 8 % calories from soybean and 8 % calories from BRS oil (BRS 50 %); and (4) C57BL/KsJ‐db/db mice fed 16 % calories from BRS oil (BRS 100 %). After 10 weeks, n‐6/n‐3 fatty acid ratios were significantly (P < 0.05) lower in the livers and epididymal adipose tissues of the BRS 50 % and BRS 100 % mice than in the CON. Serum TNFα and IL‐6 were significantly (P < 0.05) lower in the BRS 50 % and BRS 100 % than in the CON. Serum IL‐10 was significantly (P < 0.05) higher in the BRS 100 % than the CON. In the liver and epididymal adipose tissue, mRNA levels of pro‐inflammatory markers in the BRS 50 % and BRS 100 % were lower than in the CON. Anti‐inflammatory markers were higher in the epididymal adipose tissues of the BRS 50 % and BRS 100 % than in the CON. In the epididymal adipose tissue, macrophage infiltration markers (F4/80 and CD68) and leptin mRNA were significantly (P < 0.05) lower in the BRS 50 % and BRS 100 % than in the CON. Results of this study suggest that BRS oil may have anti‐inflammatory effects in obese diabetic mice by ameliorating inflammatory responses.  相似文献   
99.
A stochastic model for the calculation of flow and contaminant transport in a single fracture with variable apertures was presented. The spatially varying apertures of the fracture were generated using a geostatistical method, based on a given aperture probability density distribution and a specified spatial correlation length. Fluid flowed between two points in the fracture plane. The fluid potential at each node of the discretization mesh was computed and the steady state flow rates between all the nodes were obtained. Then the contaminant transport was calculated using a particle tracking method. The migration plumes of contaminant between the inlet and the outlet were displayed in contour plots and contaminant elution profiles were also plotted. Calculations showed that fluid flow occured predominantly in a few preferred paths. Hence, the large range of apertures in the fracture gives rise to flow channeling. Simulation results were correlated with the basic input parameters: standard deviation of a lognormal aperture distribution function and the spatial correlation length.  相似文献   
100.
A conducting diblock copolymer of PS-b-P3HT was added to serve as a compatibilizer in a P3HT/PCBM blend, which improved the power-conversion efficiency from 3.3% to 4.1% due to the enhanced crystallinity, morphology, interface interaction, and depth profile of PCBM.  相似文献   
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