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61.
Passivation behaviour of nanocrystalline coating (Fe80Si20) obtained by in situ mechanical alloying route is studied and compared with that of the commercial pure iron and cast Fe80Si20 in sodium borate buffer solution at two different pH values (7·7 and 8·4). The coating reveals single passivation at a pH of 7·7 and double stage passivity at a pH of 8·4. The first passive layer is due to the dissolution mechanism and second passivity is related to stable passivation. The cast sample shows single stage passivity in the solution of pH 8·4. The difference in the passivation behaviour for the cast alloy (Fe80Si20) and the coating is related to the presence of highly iron-enriched localized regions, formed during the processing stage of coating. 相似文献
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MIN HWAN KWAK YOUNG TAE KIM SEUNG EON MOON HAN-CHEOL RYU SU-JAE LEE KWANG YONG KANG 《Integrated ferroelectrics》2013,141(1):283-289
Ferroelectric Mn doped Ba0.5Sr0.5TiO3 (Mn-BST) films with/without BaTiO3 (BT) buffer layer have been grown on (001) MgO substrates by a pulsed laser deposition to investigate electrical tunability at microwave frequencies. Structural properties and surface morphologies of the films were investigated using an X-ray diffractometer and a scanning electron microscope, respectively. Microwave dielectric properties of Mn-BST thin films with BT buffer were studied for reduction of dielectric loss and improvement of electrical tunability. Distributed analog phase shifters have been designed and fabricated on Mn-BST films with/without BT buffer layer to understand microwave dielectric properties. The differential phase shift of the phase shifter fabricated on Mn-BST film was 22° at 10 GHz with 80 V of applied dc bias voltage. In comparison, phase shifter fabricated on Mn-BST/BT multilayers exhibit 41° of differential phase shift at the same condition. This suggests that a BT buffer layer is for microwave tunable device applications. The phase shifter fabricated on Mn-BST/BT multilayers exhibit a low insertion loss (S21) of ?1.1 dB, and a low return loss (S11) of ?14 dB with a bias voltage of 80 V. 相似文献
65.
JOON YEON CHANG INGE MOON CHONGSOOL CHOI 《Journal of Materials Science Letters》1997,16(12):1033-1036
Abstracts are not published in this journal
This revised version was published online in November 2006 with corrections to the Cover Date. 相似文献
66.
The effect of four drip irrigation rates 0, 22.7, 45.4, and 68.1 L/hr/tree (LHT) on several quality parameters of ‘Stuart’ pecans were investigated along with values calculated from inshell weights, volumes, and kernel weights. Irrigation significantly increased kernel yield/tree, nut weight, diameter, kernel specific gravity, fill of nut, oil content, and appearance rating. Values calculated by computer analyses from weights and volumes were useful for evaluating the quality of nuts from the different irrigation treatments. This technique should be useful for researchers engaged in quality evaluations of inshell pecans. Nut size and % fill, and kernel color are the best parameters to estimate quality and value of pecans before actual shelling and processing. Additionally processing costs are partially dependent on nut size (no./kg) and kernel yield. 相似文献
67.
Many optimization procedures presume the availability of an initial approximation in the neighborhood of a local or global optimum. Unfortunately, finding a set of good starting conditions is itself a nontrivial proposition. We describe a procedure for identifying approximate solutions to constrained optimization problems. Recurrent neural network structures are interpreted in the context of linear associative memory matrices. A recurrent associative memory (RAM) is trained to map the inputs of closely related transportation linear programs to optimal solution vectors. The procedure performs well when training cases are selected according to a simple rule, identifying good heuristic solutions for representative test cases. Modest infeasibilities exist in some of these estimated solutions, but the basic variables associated with true optimums are usually apparent. In the great majority of cases, rounding identifies the true optimum. 相似文献
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Do-Hoon SHIN Yun-Hae KIM Joong-Won HAN Kyung-Man MOON Ri-Ichi MURAKAMI 《中国有色金属学会会刊》2009,19(4):997-1000
IZO films were deposited onto PET substrate at room temperature with the inclined opposite target type DC magnetron sputtering equipment, in which a sintered oxide IZO target (doped with 10% ZnO, packing density of 99.99%) was used. The effects of total sputtering pressure and film thickness on IZO films properties were studied. All the films produced at room temperature have a amorphous structure, irrespective of the total sputtering pressure and film thickness. A resistivity of the order of 10−4 Ω·cm was obtained for IZO films deposited at lower pressure (film thickness of 190 nm). The resistivity of IZO films deposited at room temperature depends on film thickness and shows a minimum at a thickness of 530 nm. 相似文献
70.
SE-KWON KIM PYO-JAM PARK HEE-GUK BYUN JAE-YOUNG JE SUNG-HOON MOON SOO-HYUN KIM 《Journal of Food Biochemistry》2003,27(3):255-266
A new enzymatic treatment procedure was devised to recover and further utilize fish bones from processing which are normally discarded. This procedure includes the use of an enzyme preparation isolated from raw mackerel intestine by acetone precipitation. The caseinolytic activity of mackerel intestine crude enzyme (MICE) was approximately 0.58 U/mg protein, which was comparable to those of trypsin and α‐chymotrypsin, or even higher than those of papain and Aspergillus saitoi protease. The optimum pH, temperature and enzyme/substrate ratio of MICE for hydrolysis of protein with hoki (Johnius belengeri) frames were determined to be pH 9.0, 40C and 1:100 (w/w). When the hoki frame was treated by MICE for 6 h under the optimum reaction conditions, the yield of bone recovery was approximately 90%. Compared to Alcalase, trypsin, α‐chymotrypsin and Neutrase, the yield of bone recovery using MICE was higher. These results suggest that MICE may be utilized for bone recovery from fish frame. 相似文献