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41.
M Katsuragi K Yamamoto T Tashiro H Nishihara K Toudou 《Canadian Metallurgical Quarterly》1993,34(12):2182-2184
A myocardial 201TI SPECT examination was conducted both prior to and following surgery of two adult patients with an anomalous left coronary artery originating from the pulmonary artery (Bland-White-Garland syndrome). In this syndrome, the anterior wall is usually affected first. Preoperative examination demonstrated an inferoposterior perfusion defect. In both patients, the right coronary artery was markedly dilated, and a significant left-to-right shunt formation was observed. Both patients were diagnosed as possibly having coronary steal syndrome. A prolonged inadequate blood supply to the right coronary region may cause inferoposterior cardiomyopathy. In the postoperative examination, myocardial perfusion markedly improved in one patient whose preoperative SPECT showed redistribution in a delayed scan. Thallium-201 SPECT was therefore found to be useful in assessing both the preoperative and postoperative myocardial perfusion. 相似文献
42.
Rui Morimoto Chisato Yokomori Akiko Kikkawa Akira Izumi Hideki Matsumura 《Thin solid films》2003,430(1-2):230-235
In this paper, bulk-Si metal–oxide–semiconductor field effect transistors (MOSFETs) are fabricated using the catalytic chemical vapor deposition (Cat-CVD) method as an alternative technology to the conventional high-temperature thermal chemical vapor deposition. Particularly, formation of low-resistivity phosphorus (P)-doped poly-Si films is attempted by using Cat-CVD-deposited amorphous silicon (a-Si) films and successive rapid thermal annealing (RTA) of them. Even after RTA processes, neither peeling nor bubbling are observed, since hydrogen contents in Cat-CVD a-Si films can be as low as 1.1%. Both the crystallization and low resistivity of 0.004 Ω·cm are realized by RTA at 1000 °C for only 5 s. It is also revealed that Cat-CVD SiNx films prepared at 250 °C show excellent oxidation resistance, when the thickness of films is larger than approximately 10 nm for wet O2 oxidation at 1100 °C. It is found that the thickness required to stop oxygen penetration is equivalent to that for thermal CVD SiNx prepared at 750 °C. Finally, complementary MOSFETs (CMOSs) of single-crystalline Si were fabricated by using Cat-CVD poly-Si for gate electrodes and SiNx films for masks of local oxidation of silicon (LOCOS). At 3.3 V operation, less than 1.0 pA μm−1 of OFF leakage current and ON/OFF ratio of 107–108 are realized, i.e. the devices can operate similarly to conventional thermal CVD process. 相似文献
43.
Parameters affecting the frequencies of transformation and co-transformation with synthetic oligonucleotides in yeast. 总被引:7,自引:0,他引:7
T Yamamoto R P Moerschell L P Wakem D Ferguson F Sherman 《Yeast (Chichester, England)》1992,8(11):935-948
Factors influencing the direct transformation of the yeast Saccharomyces cerevisiae with synthetic oligonucleotides were investigated by selecting for cyc1 transformants that contained at least partially functional iso-1-cytochrome c. Approximately 3 x 10(4) transformants, constituting 0.1% of the cells, were obtained by using 1 mg of oligonucleotide in the reaction mixture. Carrier, such as heterogeneous oligonucleotides, enhanced transformation frequencies. Transformation frequencies were dramatically reduced if the oligonucleotides had a large number of mismatches or had terminally located mismatches. Transformation with oligonucleotides, but not with linearized double-strand plasmid, was efficient in a rad52- strain, suggesting that the pathway for transformation with oligonucleotides is different from that with linearized double-strand plasmid. We describe a procedure of co-transformation with two oligonucleotides, one correcting the cyc1 defect of the target allele in the host strain, and the other producing a desired amino acid alteration elsewhere in the iso-1-cytochrome c molecule; approximately 20% of the transformants obtained by co-transformation contained these desired second alterations. 相似文献
44.
Some work is so complicated and unsteady that it is not possible to use automatic robots, such as FA robots. In such a case, a teleoperated manipulation system is applied. In this research, the authors aim at a reduction in the operator's physical and mental burdens. An artificially intelligent manipulator system has been developed with nonsymmetric and redundant master-slave. This system has five features: (1) a polar coordinates master arm; (2) a highly operational articulated slave arm with 7 degrees of freedom; (3) a nonsymmetric configuration and different degrees of freedom master-slave control; (4) an expert system; and (5) a new master-slave control motion, which makes the operator's task easier with automatic force/position control. The system was experimentally produced and its performance tested and evaluated. A qualitative evaluation was carried out by conducting a comparative test on the conventional master-slave control and the new master-slave control. It was found to be effective in reducing operating time, as well as work-induced fatigue. 相似文献
45.
It is considered that refractory dissolved organic substances have caused an increase in the COD concentration in Lake Biwa in recent years. We investigated the organic matter in the first flush of stormwater runoff from a road in the watershed area of the lake, and studied the possibility of improvement in the water environment from that aspect. After percolating the stormwater through soil, we analyzed organic substances fractionated by using GPC-TC. And we examined the effect of removal of organic substances by comparing the peak height before and after percolation. In the result of the experiments, we found that soil infiltration reduced the refractory dissolved organic substance and we successfully designed a system for a simple and easy experimental facility to treat urban runoff. 相似文献
46.
Formation of dityrosine and other fluorescent amino acids by reaction of amino acids with lipid hydroperoxides 总被引:7,自引:0,他引:7
Formation of fluorescence by the reaction of various amino acids with lipid hydroperoxides,i.e., linoleic acid 13-monohydroperoxide, methyl linoleate 13-monohydroperoxide and phosphatidylcholine hydroperoxide, in the
presence of methemoglobin was investigated. Two types of fluorescence were produced: fluorescent dityrosine (3,3′-dityrosine)
from tyrosine, and unidentified fluorophores with α- and ε-amino groups of various amino acids. While the former was stable
after treatment with borohydride, the latter fluorophores were readily destroyed. The rate of dityrosine formation was rapid,
and the yield of dityrosine was dependent on the concentrations of tyrosine and the lipid hydroperoxides. Butylated hydroxytoluene
and tocopherol inhibited the formation of dityrosine, but did not affect the formation of fluorophores on the amino groups.
Dityrosine appears to be formed by radical reaction of the lipid hydroperoxides, while the other fluorophores seem to be created
by nonradical mechanisms. 相似文献
47.
We have developed a Zimm-type viscometer specially designed for the simultaneous measurements of the structure factor and the viscosity of hyperswollen lyotropic liquid crystals under a very weak shear. We have investigated the shear effects on the layer undulation fluctuation in the lamellar structure and the transition from the anisotropic lamellar to the isotropic sponge phase. We have found a significant difference in the rheological properties between the lamellar and the sponge phase: The former exhibits non-Newtonian flow behavior, while the latter exhibits Newtonian behavior.Paper presented at the Twelfth Symposium on Thermophysical Properties, June 19–24, 1994, Boulder, Colorado, U.S.A. 相似文献
48.
T Saita M Katano H Matsunaga H Yamamoto H Fujito M Mori 《Canadian Metallurgical Quarterly》1993,41(3):549-552
Antitumor polyacetylenic alcohol, panaxynol, was isolated and purified from a powder of the root of Panax ginseng C.A. Meyer. Panaxynol inhibited the growth of various kinds of cultured tumor cell lines in a dose-dependent manner. In this paper we demonstrated the first specific antibody production against panaxynol. Anti-panaxynol antibody was elicited in rabbits by immunization with panaxynol hemisuccinate-bovine serum albumin conjugate (panaxynol hemisuccinate-BSA conjugate). An enzyme immunoassay (EIA) for the determination of panaxynol was established using a double-antibody technique. The EIA was highly specific against panaxynol although the antibody showed a minimal cross-reactivity with other types of polyacetylenic alcohol, i.e. panaxydol (12.0%) and panaxytriol (0.77%). Panaxynol at a concentration as low as 6.4 ng/ml can be detected. Using this assay we reconfirmed the rapid consumption of panaxynol by target tumor cells in an in vitro-culture system. The anti-panaxynol antibody may be a valuable tool for studies of the biological properties of polyacetylenic compounds. 相似文献
49.
50.
The hydrothermal treatment of two different wood biomass samples such as cherry (hard wood) and cypress (soft wood), whose composition is different i.e. lignin, cellulose and hemicellulose were performed at 280 °C for 15 min with aq. K2CO3 with different concentrations (0–1 M). The soft wood biomass contains higher lignin content than hard wood biomass. The cellulose rich cherry wood biomass produced higher proportion of acetic acid than cypress. The lignin rich cypress produced the hydrocarbons with major portion of phenolic hydrocarbons and derivatives than cherry. The total oil yields from both cherry and cypress wood biomass produced 50 wt% of liquid hydrocarbons at 280 °C for 15 min with 0.5 M K2CO3 solution. The volatility distribution of liquid hydrocarbons showed the characteristic features of soft and hard wood biomasses. 相似文献