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排序方式: 共有1205条查询结果,搜索用时 31 毫秒
991.
An outbreak of acute hepatitis cases in a small community took place 6 months after the community's arrival to the Brazilian Amazon. An epidemiological investigation was performed and included residents aged more than two years. Study subjects were interviewed and bled to test for hepatitis markers by enzyme immunoassays. Around 80% of the village population was surveyed. The overall prevalence of hepatitis B virus (HBV) markers was 75.1% (281/374). The surface antigen of HBV (HBsAg) and the IgM class antibody against hepatitis B core antigen (IgM anti-HBc) were present in 10.4% and 9.6%, respectively. Evidence of HBV-HDV (Delta virus) coinfection or hepatitis C infection was not found. IgM class antibody against hepatitis A virus was uncommon (3.7%). Follow-up evaluation 6 and 12 months later were carried out to identify new HBV infections. An incidence rate of 7.2 new infections per 100 exposed subjects per month was found. Average individual risk for HBV infection among susceptible inhabitants of the village between June 1995 and June 1996 can be estimated at 57.6%. The predominant HB-sAg subtype found (ayw3) suggests that immigrants may have carried HBV from the original area. Time living in the study region was significantly associated with HBV markers in analysis for linear trend and logistic regression analysis. Environmentally related factors may have facilitated HBV transmission. 相似文献
992.
S. Osono Y. Uchiyama M. Kitazoe K. Saito M. Hayama A. Masuda A. Izumi H. Matsumura 《Thin solid films》2003,430(1-2):165-169
The coverage properties of silicon nitride (Si3N4) films prepared by the catalytic chemical vapor deposition (Cat-CVD) technique were systematically studied. By increasing the catalyzer–substrate distance, the coverage was improved from 46 to 67% on a 1.0-μm line and space pattern. The etching rate of Cat-CVD Si3N4 film measured using 16BHF solution was independent of the deposited position of the micro-patterns deposited, and was approximately 3 nm/min, one order of magnitude lower than that of plasma-enhanced CVD (PE-CVD) Si3N4 film. This means that Cat-CVD Si3N4 films are denser than PE-CVD Si3N4 films, and that the quality at the side wall is equivalent to that on the top surface. That is, Cat-CVD Si3N4 films show a passivation effect, which was excellent, even at the side wall of micro-patterns. These results suggest that Si3N4 films prepared by Cat-CVD are suitable for the passivation films in microelectronic devices having a step configuration, such as TFT-LCDs and ULSIs. 相似文献
993.
Keiji Ishibashi Minoru Karasawa Ge Xu Naoaki Yokokawa Manabu Ikemoto Atsushi Masuda Hideki Matsumura 《Thin solid films》2003,430(1-2):58-62
Thin film deposition on large-area substrates of 1-m size is demonstrated by catalytic chemical vapor deposition (Cat-CVD) apparatus equipped with a newly developed showerhead catalyzer unit. The arrangement of catalyzer wires for uniform film thickness was determined by simulation, assuming that decomposed species on catalyzers were transported by isotropic thermal diffusion without an influence of the gas flow. A film thickness uniformity of ±7.5% was successfully achieved on a substrate of 400 mm×960 mm at an average deposition rate of 32 nm/min for hydrogenated amorphous silicon (a-Si:H) film. Film thickness uniformity of ±8.6% for a-Si:H film and ±12.3% for silicon nitride film were also successfully obtained on substrates of 680 mm×880 mm size at an average deposition rate of 12.1 and 2.5 nm/min, respectively. These results suggest that Cat-CVD is a promising method for the fabrication of large-area devices such as thin-film-transistor liquid-crystal displays and solar cells. 相似文献
994.
A total of 1,207 patients received a Medtronic Jewel active can ICD (models 7218C, 7219C), with a Transvene lead in 97 centers in Europe and North America. Nineteen implants were from the right pectoral region. Patients with right-sided ICDs did not differ in terms of mean age, % male, left ventricular ejection fraction, New York Heart Association Functional Class, antiarrhythmic drug therapy, indication for the implantable cardioverter defibrillator, and R wave values at implantation, but tended to have slightly higher pacing thresholds (1.2 +/- 0.5 V vs 1.0 +/- 0.6 V, P = 0.012) and higher defibrillation thresholds (14.7 +/- 6.4 J vs 11.5 +/- 6 J, P = 0.11) compared with patients with left sided implants. Patients with right-sided implants had a longer implantation time compared with patients with left-sided implants (118 +/- 70 minutes vs 91 +/- 46 minutes, P = 0.074). In follow-up, 5 patients with right-sided implantation received successful therapy for either ventricular fibrillation, (8 episodes) or ventricular tachycardia (5 episodes). No ineffective therapy from the device was delivered in any patients with right-sided implantation. Right-sided pectoral implants are feasible with the Medtronic Jewel active can ICD. 相似文献
995.
996.
A technique for predicting wafer temperature was developed, and a model for predicting critical dimension (CD) was devised. Using this technique and model in combination makes it possible to calculate wafer temperature during gate etching within an accuracy of 1 °C and to predict CD distribution after plasma etching. Etching at a temperature for uniform CD given by the CD prediction model reduces the CD variation (3σ) during gate etching from 2.3 to 1.5 nm. Applying this temperature prediction technique and CD prediction model together will contribute to improving etching apparatus design and process development. 相似文献
997.
998.
Atmospheric correction of ASTER 总被引:1,自引:0,他引:1
Thome K. Palluconi F. Takashima T. Masuda K. 《Geoscience and Remote Sensing, IEEE Transactions on》1998,36(4):1199-1211
An atmospheric correction algorithm for operational use for the high-spatial resolution, Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) is presented. The correction is a straightforward approach relying on inputs from other satellite sensors to determine the atmospheric characteristics of the scene to be corrected. Methods for the solar reflective and thermal infrared (TIR) are presented separately. The solar-reflective approach uses a lookup table (LUT) based on output from a Gauss-Seidel iteration radiative transfer code. A method to handle adjacency effects is included that relies on model output, assuming a checkerboard surface. An example of a numerical simulation shows that the effect of a land surface on the radiance over the ocean is stronger just off the coastal zone and decreases exponentially with increasing distance from the land. A typical numerical simulation is performed over the Tsukuba lake area in Japan. The TIR approach relies on the radiative transfer code Moderate Resolution Atmospheric Radiance and Transmittance Model (MODTRAN). The code is run for a given set of atmospheric conditions for multiple locations in the scene for several representative elevations. Pixel-by-pixel radiances are then found using spatial interpolation. Sensitivity analysis of the methods indicate that the results of the atmospheric correction will be limited by the accuracies of the input parameters 相似文献
999.
Long-term clinical outcome of extracorporeal shock wave lithotripsy monotherapy for staghorn calculi
S Ashida A Yamamoto N Oka S Masuda K Yuasa N Terao 《Canadian Metallurgical Quarterly》1998,44(8):541-546
The thickness (TBmt) and fiber pennation angle (TBpen) of triceps brachii as well as isokinetic force developed during elbow extension were measured in Olympic athletes to investigate the relationship between muscle fiber pennation and force generation capability. The subjects were male members of the 1996 Japanese Olympic team who competed in seven different events; 9 wrestlers, 16 soccer players, 11 sprinters, 5 judo athletes, 7 gymnasts, 9 rowers and 18 baseball players. The TBmt and TBpen, measured by a B-mode ultrasound, ranged between 29 mm and 50 mm and between 11 degrees and 30 degrees, respectively, and on average were larger in the judo athletes, wrestlers and gymnasts compared to the other groups. A significant correlation (r=0.580, p < 0.05) was found between TPpen and TBmt per unit of the upper arm length, and so the observed event-related differences in TBpen tended to reflect the differences in TBmt. The isokinetic forces relative to the cross-sectional area (CSA) estimated from TBmt, measured at two constant velocities of 1.05 rad/s (F1.05/CSA) and 3.14 rad/s (F3.14/ CSA), were negatively correlated to the CSA; r=-0.617 (p < 0.05) for F1.05/CSA and r=-0.635 (p < 0.05) for F3.14/CSA. In addition, low but significant negative correlations existed between TBpen and both F1.05/CSA (r=-0.365, p < 0.05) and F3.14/ CSA (r=-0.336, p <0.05). Even when the effect of TBpen was statistically normalized, the F1.05/CSA and F3.14/CSA were still negatively correlated to the CSA, r=-0.530 (p < 0.05) for F1.05/ CSA and r=-0.561 (p < 0.05) for F3.14/CSA. Therefore, at least in the Olympic athletes tested in this study, the magnitude of the pennation angles reflects muscle size, but it does not seem to be a factor that explains extensively the lower F/CSA in athletes with large muscle size. 相似文献
1000.
An extremely large seamless gain-bandwidth of 135 nm (1497-1632 nm) with a minimum gain of 22.8 dB is achieved with a novel hybrid tellurite/silica fibre Raman amplifier. The amplifier is used successfully as a pre-amplifier in a WDM transmission experiment 相似文献