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951.
952.
V. P. Parafeinik 《Chemical and Petroleum Engineering》2007,43(7-8):485-493
Schemes are analyzed for turbocompressor installations (TCI) with a gas turbine drive (GTD) for collecting and transporting
petroleum gas (PG) and natural gas (NG). The makeup of the equipment for an NG TCI setup based on a GTD of the aircraft or
ship type is considered. Energy characteristics of the NG TCI and PG GTD are provided. A procedure for energy analysis of
the TCI is developed.
__________
Translated from Khimicheskoe i Neftegazovoe Mashinostroenie, No. 8, pp. 44–48, August, 2007.
From the editor. According to the certificate of the international bureau Marquis Who’s Who (USA) the biography of the author of this article
V. P. Parafeinik as a specialist in the field of oil and gas equipment is included in the annual catalog Who’s Who in the
World (24, p. 1954) for 2007. 相似文献
953.
954.
Carrot slices of 3.5 mm thickness were dried in a laboratory microwave vacuum dryer at five different microwave power density levels of 2, 4.66, 7.33, 10, and 12.66 W/g and at three vacuum chamber pressure levels of 6.66, 19.98, and 33.3 kPa to 4-6% d.b. moisture content. Inside the dryer the sample holding plate was rotated with the speed of 4 rpm for uniform microwaves application. The drying rates were increased with the increase in microwave power density at all pressure levels and the Page model was found to be the most suitable model to predict the drying behavior of carrot slices at all process conditions. The Page model drying rate constant (k, min-1) showed high correlation with microwave power density at constant pressure by a power law equation and showed a logarithmic relationship with the microwave power density and pressure. Similar to the drying rate constant, the average moisture diffusivity at constant pressure was found to be function of microwave power density by power law equation as well as was also dependent on the power density and pressure by a logarithmic relationship. 相似文献
955.
The influence of nonionic surfactants (polysorbates) on hydrocortisone penetration through hairless mouse skin in vitro has been determined. Permeation was quite slow from purely aqueous media containing surfactants following finite dose application. However, if the vehicle contained high propylene glycol concentrations (40% or more), inclusion of a surfactant increased permeation rate significantly. Similar effects were noted following application of a large donor volume (infinite dose). Synergism was attributed to enhancement of surfactant absorption by the stratum corneum leading to changes in skin barrier resistance. With vehicles containing a surfactant, penetration was higher after finite dose application due to compositional changes within the vehicle. 相似文献
956.
957.
958.
H.-J. Gehrhardt J. Eisenbltter P. Jax H.-J. Maier E. Waschkies 《Nuclear Engineering and Design》1987,102(3)
The investigations were aimed at demonstrating the state of the art of acoustic emission testing (AET) of reactor pressure vessels. The object under investigation was the large reactor pressure vessel of the MPA in Stuttgart, a boiling-water reactor pressure vessel, which was provided with a multitude of flaws in weld seams and in the base material. Six hydrostatic tests approximately up to the working pressure of a boiling-water reactor (71 bar) were carried out. In addition to the global multichannel locating technique, also local monitoring techniques were applied. Global location permitted a large number of different indications to be detected simultaneously. Not all of the known flaws did, however, show the expected number of AE events. On the other hand, it was possible to detect flaws previously unknown to the AE staff in some weld seams; these indications were confirmed by nondestructive testing. It was demonstrated that the locating accuracy of local monitoring using signal analysis was improved by a factor of 20 to 30 compared to global monitoring. 相似文献
959.
K Lenz S N Mahnik N Weissenbacher R M Mader P Krenn S Hann G Koellensperger M Uhl S Knasmüller F Ferk W Bursch M Fuerhacker 《Water science and technology》2007,56(12):141-149
Cytostatic agents are applied in cancer therapy and subsequently excreted into hospital wastewater. As these substances are known to be carcinogenic, mutagenic and toxic for reproduction, they should be removed from wastewater at their source of origin.In this study the fate and effects of the cancerostatic platinum compounds (CPC) cisplatin, carboplatin, oxaliplatin, 5-fluorouracil (5-FU) and the anthracyclines doxorubicin, daunorubicin and epirubicin were investigated in hospital wastewater. Wastewater from the in-patient treatment ward of a hospital in Vienna was collected and monitored for the occurrence of the selected drugs. A calculation model was established to spot the correlation between administered dosage and measured concentrations. To investigate the fate of the selected substances during wastewater treatment, the oncologic wastewater was treated in a pilot membrane bioreactor system (MBR) and in downstream advanced wastewater treatment processes (adsorption to activated carbon and UV-treatment). Genotoxic effects of the oncologic wastewater were assessed before and after wastewater treatment followed by a risk assessment.Monitoring concentrations of the selected cytostatics in the oncologic wastewater were in line with calculated concentrations. Due to different mechanisms (adsorption, biodegradation) in the MBR-system 5 - FU and the anthracyclines were removed < LOD, whereas CPC were removed by 60%. In parallel, genotoxic effects could be reduced significantly by the MBR-system. The risk for humans, the aquatic and terrestrial environment by hospital wastewater containing cytostatic drugs was classified as small in a preliminary risk assessment. 相似文献
960.
P Lipponen S Aaltomaa M Eskelinen M Ala-Opas VM Kosma 《Canadian Metallurgical Quarterly》1998,34(3):237-243
Selective antagonists to the Type 3 serotonin receptor (5HT3) in combination with corticosteroids are now considered the standard of care for the prevention of emesis from moderately to highly emetogenic chemotherapy. Here we address issues of optimal dose, schedule and route of administration of four currently available selectable 5HT3 antagonists. This paper utilizes an evidence based medicine approach to the literature regarding this class of drugs, emphasizing the results large, randomized, controlled trials to make formal recommendations concerning optimal use of this important new class of anti-emetic agents. We conclude that for each drug there is a plateau in therapeutic efficacy at a definable dose level above which further dose escalation does not improve outcome. Furthermore, a single dose is as effective as multiple doses or continuous infusion, and finally, emerging data demonstrate that the oral route is equally efficacious as the intravenous route of administration, even with highly emetogenic chemotherapy. 相似文献