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91.
The antioxidant activities and nutritional properties of Jeonyak made with beef bone stock and gelatin were investigated. Traditional Jeonyak (J1) was prepared with beef bone stock, whereas modified Jeonyak was made with gelatin and honey (J2) or with gelatin and oligosaccharides (J3). All 3 kinds of Jeonyak had antioxidant activities and J1 had the highest activity. The α-glucosidase inhibitory activity was measured to investigate the antidiabetic effect and J3 had the highest inhibitory activity of 80.47%. Glycine was the most abundant amino acid in all 3 kinds of Jeonyak. Both traditional and modified Jeonyaks have antioxidative and antidiabetic effects, suggesting that Jeonyak can be used as an effective traditional functional food. 相似文献
92.
Ki Yong Lee Andrew Lock Anthony Hamins 《Journal of Mechanical Science and Technology》2011,25(8):2035-2041
A set of experiments has been conducted on a medium-scale propane fueled pool fire acoustically forced in order to facilitate
repeatable measurements defining the flame’s transient behavior. The fuel flow was slightly perturbed at the pool fire’s natural
frequency by a sine waveform driven with a loudspeaker which was installed under the burner. As a result of the perturbation,
the puffing behavior of the pool fire and the fire shape were modified. As the magnitude of the sine wave was increased larger
perturbations were clearly observed, based on the measurement of the radiative heat flux and image analysis. Temperature and
soot volume fractions were measured along the center line and throughout a slice of the flame. The soot volume fractions in
the flame region are in good agreement with the data of other researchers. The reproducibility of these measurements was established
through several experiments. The acoustically driven flame provides the possibility of more repeatable measurements of the
transient behavior of these pool fires. 相似文献
93.
Chang Won Ahn Hee Sung Kim Won Seok Woo Sung Sik Won Hae Jin Seog Song A Chae Bong Chan Park Ki Bong Jang Yun Po Ok Hyon Ho Chong Ill Won Kim 《Journal of the American Ceramic Society》2015,98(6):1877-1883
We investigated the influence of CuO amount (0.5–3.0 mol%), sintering temperature (900°C–1000°C), and sintering time (2–6 h) on the low‐temperature sintering behavior of CuO‐added Bi0.5(Na0.78K0.22)0.5TiO3 (BNKT22) ceramics. Normalized strain (Smax/Emax), piezoelectric coefficient (d33), and remanent polarization (Pr) of 1.0 mol% CuO‐added BNKT22 ceramics sintered at 950°C for 4 h was 280 pm/V, 180 pC/N, and 28 μC/cm2, respectively. These values are similar to those of pure BNKT22 ceramics sintered at 1150°C. In addition, we investigated the performance of multilayer ceramic actuators made from CuO‐added BNKT22 in acoustic sound speaker devices. A prototype sound speaker device showed similar output sound pressure levels as a Pb(Zr,Ti)O3‐based device in the frequency range 0.66–20 kHz. This result highlights the feasibility of using low‐cost multilayer ceramic devices made of lead‐free BNKT‐based piezoelectric materials in sound speaker devices. 相似文献
94.
The effect of BMP‐2 and VEGF loading of gelatin‐pectin‐BCP scaffolds to enhance osteoblast proliferation 下载免费PDF全文
A composite scaffold of gelatine (Gel)‐pectin (Pec)‐biphasic calcium phosphate (BCP) was successfully fabricated. Growth factors such as bone morphogenetic protein‐2 (BMP‐2) and vascular endothelial growth factor (VEGF) were loaded into the Gel‐Pec‐BCP hydrogel scaffolds by freeze‐drying. The surface morphology was investigated by scanning electron microscopy, and BCP dispersion in the hydrogel scaffolds was measured by energy dispersive and X‐ray diffraction spectroscopy. The results obtained from Fourier transform infrared spectroscopy and quantitative measurements showed successfully loading of BMP‐2 and VEGF into the Gel‐Pec‐BCP hydrogel scaffolds. In addition MC3T3‐E1 preosteoblasts were cultivated on the three types of scaffolds to investigate the effects of BMP‐2 and VEGF on cell viability and proliferation. The Gel‐Pec‐BCP scaffolds loaded with VEGF and BMP‐2 demonstrated more cell spreading and proliferation compared to those of the Gel‐Pec‐BCP scaffolds. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015 , 132, 41241. 相似文献
95.
High Charge‐Carrier Mobility of 2.5 cm2 V−1 s−1 from a Water‐Borne Colloid of a Polymeric Semiconductor via Smart Surfactant Engineering 下载免费PDF全文
96.
97.
High‐Performance All‐Polymer Solar Cells Via Side‐Chain Engineering of the Polymer Acceptor: The Importance of the Polymer Packing Structure and the Nanoscale Blend Morphology 下载免费PDF全文
98.
Fikret Kocabaş Özgür Kişi Mehmet Ardiçlioğlu 《Civil Engineering and Environmental Systems》2013,30(4):367-375
Density differences may occur because of temperature differentials, suspended sediments, dissolved salts or other chemicals. Most of the large surface reservoirs are stably stratified throughout most, or all, of the year. One of the means of assisting the management is to allow a selective withdrawal from the reservoir. And while an intake is used for withdrawal (from the lower layer), a maximum discharge is required not allowing the uptake of the upper layer fluids. The value of the intake's vertical distance from the upper layer elevation (submergence) when the upper layer fluids begin to be drawn into the intake is known as ‘critical submergence’. In this study, the critical submergence for a circular intake pipe in a stratified body (which has different layer thickness) is investigated. Experiments were conducted on a vertically flowing downward intake pipe in a still-water reservoir. Artificial neural network (ANN) models and formulas, which are found by the theoretical analysis of critical spherical sink surface (CSSS), are used for the analysis of experimental results. The CSSS has the same centre and discharge as the intake. The ANN model and CSSS results are compared with the experimental results. 相似文献
99.
Dispersant‐free dyeing of poly(lactic acid) fabric with temporarily solubilised disperse dyes from azopyridone derivatives 下载免费PDF全文
Poly(lactic acid) fibre is derived from annually renewable crops and known to be 100% compostable. In order to extend its environmental friendliness into the dyeing process, dispersant‐free dyeing of poly(lactic acid) fabric with three temporarily solubilised azo disperse dyes based on hydroxypyridone moiety containing a β‐sulphatoethylsulphonyl group was investigated. The dyes were successfully applied to poly(lactic acid) fabric without the use of dispersants. The colour yields of the dyes on poly(lactic acid) fabric were observed to be dependent on dyebath pH and dyeing temperature. The optimum results were obtained at pH 4–5 and 110 °C. One of the dyes showed a colour yield as good as that of a commercial disperse dye and good build‐up on poly(lactic acid) fabric. All of the dyes could be alkali cleared owing to ionisation of the dye under mild alkaline conditions. Wash fastness was good to very good, and light fastness was good. The chemical oxygen demand levels of the poly(lactic acid) dyeing effluent from the dyes were considerably lower than those from a commercial disperse dye. 相似文献
100.
Joung Hyun La Ki Tae Bae Sang Yul Lee Myung Kon Song Kyung Hoon Nam Yong Hwa Jung 《Journal of Mechanical Science and Technology》2016,30(10):4417-4421
For the purpose of utilizing induction heating in the evaporation process, the effects of induction coil design and droplet size on induction heating efficiency are investigated. Electro-magnetic simulations with various induction coil designs were conducted to predict the electro-magnetic field distribution. The induction coils were fabricated in order to verify the simulation results under atmospheric evaporation test conditions. The electro-magnetic simulation results indicated that the magnetic field became widened around the Zn droplet when the size of the Zn droplet increased. This in turn attributed to the increase in induction heating energy efficiency. The energy efficiency of the induction coil with 4-windings was the highest among the 3-, 4-, and 5-windings induction coils. Energy efficiency tendencies derived by the atmospheric evaporation tests corresponded well to the simulation results, and maximum energy efficiency was measured to be 42% under the atmospheric evaporation tests. 相似文献