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81.
A tannin gel (TG) synthesized from condensed tannin molecules has a remarkable ability to adsorb various metal ions in aqueous solutions. In the present study, the adsorption removal of boron in solutions at various pHs and temperatures has been examined using the TG and the amine-modified tannin gel (ATG) prepared with ammonia treatment of the TG. The adsorption amounts of boron for the TG and the ATG were relatively small and almost constant below pH 7, whereas the boron adsorption amounts increased with increasing pH in the range of pH above 7. Considering that in aqueous solutions above pH 7, the mole fraction of boric acid decreases while that of tetrahydroxyborate ion increases with increasing pH, the boron adsorption onto both gels takes place probably through the chelate formation of tetrahydroxyborate ion with the hydroxy and the amino groups in the gels. Besides, the adsorbability of the ATG for boron was higher than that of the TG due to the stable coordination bond between boron and nitrogen of the amino group in the ATG. The adsorption kinetics were adequately described by the pseudo-second order kinetic equation while the adsorption isotherms followed both the Langmuir and the Freundlich equations. The boron adsorbability of both the TG and the ATG at low boron concentration were comparable or fairly good compared with other adsorbents. 相似文献
82.
83.
Undeclared food allergens due to cross contamination of processing equipment is a leading cause for food product recalls. Therefore, there is a great need for developing rapid and sensitive methods to detect food allergens. In this paper, an aptamer highly specific to egg white lysozyme was coupled to dendritic silver nanoparticles in order to perform surface enhanced Raman spectroscopy (SERS). The procedure was successfully tested in water and on a stainless steel food‐handling surface. The lowest detectable concentration for lysozyme was 0.5 μg/mL in water and 5 μg/mL on a stainless steel food‐handling surface. Principal component analysis shows a significant change in SERS spectra when lysozyme was present, suggesting the successful capture of lysozyme by the aptamer. Quantification of lysozyme target was also shown from 0 to 6 μg/mL, that is, 0, 0.5, 2, 6 μg/mL. Overall method took less than 40 min. The developed method can be extended to detect other food allergens using specific aptamers. 相似文献
84.
Shintaro OsadaYasuhiro Abe Takaya AnegawaTakashi Minemoto Hideyuki Takakura 《Solar Energy Materials & Solar Cells》2011,95(1):223-226
Cu(In,Ga)Se2 (CIGS) solar cells with a superstrate structure were fabricated using a lift-off process. To widen the variety of substrate choices for CIGS solar cells, a lift-off process was developed without an intentional sacrificial layer between the CIGS and Mo back-contact layers. The CIGS solar cells fabricated on Mo/soda-lime glass (SLG) were transferred to an alternative SLG substrate. The conversion efficiency of the CIGS solar cells with the superstrate structure was 5.1%, which was almost half that of the CIGS solar cells with a substrate structure prior to the lift-off process. The low conversion efficiency was caused by the high series resistance and low shunt resistance, which would be due to the junction resistance between the CIGS/back contact and cracks introduced during the lift-off process, respectively. 相似文献
85.
The hydrogenation of CO over an Rh vanadate (RhVO4) catalyst supported on SiO2 (RhVO4/SiO2) has been investigated after H2 reduction at 500°C, and the results are compared with those of vanadia-promoted (V2O5–Rh/SiO2) and unpromoted Rh/SiO2 catalysts. The mean size of Rh particles, which were dispersed by the decomposition of RhVO4 after the H2 reduction, was smaller (41 Å) than those (91–101 Å) of V2O5–Rh/SiO2 and Rh/SiO2 catalysts. The RhVO4/SiO2 catalyst showed higher activity and selectivity to C2 oxygenates than the unpromoted Rh/SiO2 catalyst after the H2 pretreatment. The CO conversion of the RhVO4/SiO2 catalyst was much higher than that of V2O5–Rh/SiO2 catalyst, and the yield of C2 oxygenates increased. We also found that the RhVO4/SiO2 catalyst can be regenerated by calcination or O2 treatment at high temperature after the reaction. 相似文献
86.
Interlayer Pd for the Li/Pd/Cu neutron target for BNCT (boron neutron capture therapy) was characterized after 0.1-5 keV H2^+ irradiation by XAFS (X-ray absorption fine structure) technique, and following conclusions were derived: (1) from the XAFS observation of white line of Pd, remarkable Pd L3 edge jump was found in 1.1-3 times higher than before irradiation in low irradiation fluence; (2) this fact indicates increase of hole density in Pd 4d-band, whereas, no change was observed for XASF spectra of Ag sample under the same irradiation conditions; (3) remarkable Pd L3 edge shift of 0.12-0.66 eV was also found with increase of H2+ irradiation energy in low fluence, and drastically decreased after peak in high irradiation energy and fluence; (4) implanted protons deposited in Pd as negative under the balance of electron population enhanced by proton irradiation and charge transfer. 相似文献
87.
88.
We have studied the Brazil Nut effect – the rise of a large intruder particle within a vertically vibrated bed of smaller particles. In our study both intruder and bed particles were spherical and the vibration was such that bed convection was negligible. The rise of the intruder was found to be influenced by humidity of the air within the interstices of the particle bed and on the electrostatic charge developed on the bed particles during preparation and vibration. High relative humidity and high electrostatic charge each had the effect of slowing the rise of the intruder. Because increasing relative humidity of the interstitial air caused the electrostatic charge to diminish, the rise rate of the intruder achieved a maximum at a relative humidity of around 55%. Under controlled humidity and charge conditions, the time for the intruder to rise through the bed was found to decrease with increase in intruder diameter. As intruder density was varied under controlled humidity and charge conditions, the intruder rise time was found to exhibit a maximum when the intruder density of approximately one half of the bulk density of the bed of particles. This interesting trend was modelled by taking account of the pressure gradient that is generated across a bed of particles vertically vibrated within a gas. The tentative model suggests that the gas flows associated with this pressure gradient restrict the motion of the bed more than that of the intruder and that it is this difference that accounts for the rise of the intruder. Also incorporated in the model is the buoyancy force on the intruder that results from the pressure gradient across the bed. KeywordsBrazil nut effect, Vibration, Granular solids, Humidity, Electrostatics, Interstitial air
Dr. Shintaro Takeuchi is a Research Fellow of the Japan Society for the Promotion of Science (JSPS). Ms. Muniandy received financial support from CSIRO grant CZ-25. 相似文献
89.
90.
Shuzo Hattori Junji Tamano Masao Yamada Masayuki Ieda Shinzo Morita Katsumi Yoneda Shintaro Ishibashi 《Thin solid films》1981,83(2):189-194
A completely dry lithography has been proposed which involves plasma polymerization of methyl methacrylate (MMA) and plasma development with CCl4. It was called vacuum lithography because all processes were performed in a vacuum. However, the developed pattern had a lower resolution than patterns produced by conventional lithography with a wet process. After several technical refinements, the quality of the resist and the developed pattern was markedly improved. In this paper, recent results will be reported.A gas-flow-type reactor was used instead of a bell-jar-type reactor because the morphology of plasma-polymerized MMA (PPMMA) varied with each experimental run which was performed with the same gas and discharge parameters. The monomer vapour was introduced downstream of the argon discharge, and the polymerized film was formed on the substrate placed further downstream in the mixed gas.The development of pattern was performed by etching with an Ar-O2 mixture and with hydrogen gas instead of CCl4 gas, because the etching rate of the resist was too high in a CCl4 plasma and a clear pattern was not obtained. The evaluated sensitivity and γ value of PPMMA were 1000 μC cm?2 and 1 respectively. MMA containing 5% tetramethyltin was also used as a monomer gas for plasma polymerization downstream of the argon discharge. In this case the sensitivity and γ value were 10 μC cm?2 and 2 respectively. 相似文献