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101.
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A review of 1,000 consecutive coronary angiograms, most of them performed for evaluation of angina pectoris, yielded 9 examples of congenital anomalies of the coronary arteries. In 2 cases the angina may have been due to malposition of the left coronary artery or one of its branches. There were 2 cases of aberrant origin of the circumflex artery from the right coronary artery, 2 cases of aberrant left anterior descending artery, 3 cases in which all three major coronary branches arose from the right aortic sinus, and 2 cases of coronary artery fistulas. Malposition of the coronary artery should be considered as a possible cause of angina. 相似文献
104.
105.
Pfiester J.R. Baker F.K. Sivan R.D. Crain N. Lin J.-H. Liaw M. Seelbach C. Gunderson C. Denning D. 《Electron Device Letters, IEEE》1990,11(6):253-255
An inverse-T lightly doped drain (ITLDD) CMOS process which features improved hot-carrier effects and self-aligned source/drain and channel implantation profiles is presented. Compensation effects by the heavy channel doping on the light N-/P- profile are minimized in this ITLDD structure, because the implants are self-aligned to the polysilicon-gate edge. In addition, because selective polysilicon deposition rather than an incomplete poly-gate etchback is used to define the ITLDD structure, a simpler, more manufacturable process is obtained due to improved control of the thin poly-gate shelf thickness 相似文献
106.
By using fiber gratings as pump reflectors with various reflectivities or N pieces of gain fibers with various lengths externally to linear cavity as self-equalizers, a parallel-type, pump-shared linear cavity laser array (LCLA) is proposed and numerically studied. The average output power is increased and the maximum power variation among channels is reduced from 7.2 to less than 0.1 dB when the reflectivity of each pump reflector or the length of each gain fiber is adjusted appropriately 相似文献
107.
108.
Kao-Shang Shih Ching-Chi Hsu Tzu-Pin Hsu Sheng-Mou Hou Chen-Kun Liaw 《Computer methods and programs in biomedicine》2014
Femoral shaft fractures can be treated using retrograde interlocking nailing systems; however, fracture nonunion still occurs. Dynamic fixation techniques, which remove either the proximal or distal locking screws, have been used to solve the problem of nonunion. In addition, a surgical rule for dynamic fixation techniques has been defined based on past clinical reports. However, the biomechanical performance of the retrograde interlocking nailing systems with either the traditional static fixation technique or the dynamic fixation techniques has not been investigated by using nonlinear numerical modeling. Three-dimensional nonlinear finite element models were developed, and the implant strength, fixation stability, and contact area of the fracture surfaces were evaluated. Three types of femoral shaft fractures (a proximal femoral shaft fracture, a middle femoral shaft fracture, and a distal femoral shaft fracture) fixed by three fixation techniques (insertion of all the locking screws, removal of the proximal locking screws, or removal of the distal locking screws) were analyzed. The results showed that the static fixation technique resulted in sufficient fixation stability and that the dynamic fixation techniques decreased the failure risk of the implant and produced a larger contact area of the fracture surfaces. The outcomes of the current study could assist orthopedic surgeons in comprehending the biomechanical performances of both static and dynamic fixation techniques. In addition, the surgeons could also select a fixation technique based on the specific patient situation using the numerical outcomes of this study. 相似文献
109.
HW Yoon MC Kim PG Shin JS Kim CY Kim SY Lee I Hwang JD Bahk JC Hong C Han MJ Cho 《Canadian Metallurgical Quarterly》1997,255(4):359-371
Two soybean cDNA clones, SPK-3 and SPK-4, encoding putative protein kinases were isolated and characterized. Both cDNAs encoded approximately 40-kDa serine/threonine kinases with unusual stretches of acidic amino acids in their carboxy-terminal regions, which are highly homologous to PKABA1 from wheat and ASKs from Arabidopsis. These kinases are encoded by one- or two-copy genes in the soybean genome. Notably, SPK-3 and -4 showed different patterns of expression in various soybean tissues. SPK-3 is highly expressed in dividing and elongating tissues of young seedlings but relatively weakly in tissues of mature plants. In contrast, SPK-4 showed relatively high and constitutive expression in all the tissues examined except for leaf tissues of mature plants. Although various stressors, such as dehydration and high salinity, increased the expression of both genes, the induction kinetics were different. The two genes also differed in their response to abscisic acid (ABA). SPK-3 was induced but SPK-4 was not affected by exogenously supplied abscisic acid. In accordance with these expression data analysis of the activity of a chimeric SPK-3 promoter::beta-glucuronidase (GUS) reporter gene by transient expression in tobacco leaves confirmed the inducibility of SPK-3 by salt and ABA. Polyclonal antibodies raised against a recombinant SPK-4 protein produced in Escherichia coli specifically recognized both recombinant SPK-3 and -4 proteins. Kinase assays using affinity-purified SPK-4/ antibody complexes with crude soybean extracts as substrate identified specific phosphorylation of two 41 and 170 kDa soybean proteins that were phosphorylated on serine residues. Taken together, our results suggest that SPK-3, and/or SPK-4 are functional serine protein kinase(s). Furthermore, SPK-3 and -4 may play different roles in the transduction of various environmental stresses. 相似文献
110.
P. K. Liaw M. N. Gungor W. A. Logsdon Y. Ijiri B. J. Taszarek S. Frohlich 《Metallurgical and Materials Transactions A》1990,21(2):529-538
Interfaces of two different babbitt-bronze composites were tested ultrasonically and then were fractured using the Chalmers
test method. The primary distinction between the two composites was in the copper content. Use of less copper in the babbitt
resulted in interfaces with higher strength, lower ductility, less cracking, and less unbonded area. The differences appeared
to stem from the structure of the intermetallic compounds found at the interface, namely, the Cu3Sn and the Cu6Sn5 layers. The low-copper composite failed within a thick, dendrite-like Cu6Sn5 layer, while the high-copper one separated at the interface between a smooth Cu6Sn5 layer and the babbitt metal. The rough interface morphology seemed responsible for the low-copper composite’s increased strength.
The correlation between mechanical and ultrasonic properties was poor for the low-copper composite but excellent for the high-copper
one. These results suggest that interface morphology can significantly affect mechanical as well as ultrasonic properties.
Formerly with the Westinghouse Power Systems Operations Division
Formerly with the Westinghouse Science and Technology Center 相似文献