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141.
The number of diabetes mellitus (DM) patients is increasing, and stroke is deeply associated with DM. Recently, neuroprotective effects of glucagon-like peptide-1 (GLP-1) are reported. In this study, we explored whether liraglutide, a GLP-1 analogue exerts therapeutic effects on a rat stroke model. Wistar rats received occlusion of the middle cerebral artery for 90 min. At one hour after reperfusion, liraglutide or saline was administered intraperitoneally. Modified Bederson’s test was performed at 1 and 24 h and, subsequently, rats were euthanized for histological investigation. Peripheral blood was obtained for measurement of blood glucose level and evaluation of oxidative stress. Brain tissues were collected to evaluate the level of vascular endothelial growth factor (VEGF). The behavioral scores of liraglutide-treated rats were significantly better than those of control rats. Infarct volumes of liraglutide-treated rats at were reduced, compared with those of control rats. The level of derivatives of reactive oxygen metabolite was lower in liraglutide-treated rats. VEGF level of liraglutide-treated rats in the cortex, but not in the striatum significantly increased, compared to that of control rats. In conclusion, this is the first study to demonstrate neuroprotective effects of liraglutide on cerebral ischemia through anti-oxidative effects and VEGF upregulation.  相似文献   
142.
Abstract

Hexagonal YMnO3 thin films were prepared on Pt(111)/TiOx/SiO2/Si and Pt(111)/Al2O3(0001) substrates using alkoxy-derived precursor solutions. The films were prepared by spin coating the YMnO3 precursor solutions and then, the films were calcined and crystallized via rapid thermal annealing in oxygen or vacuum ambient. The annealing conditions and substrates were critical for crystallization of ferroelectric YMnO3 films. When annealed in vacuum, the films both on Pt(111)/TiOx/SiO2/Si and Pt(111)/Al2O3(0001) substrates crystallized to hexagonal YMnO3 and the orientation depended on the substrates. The film on Pt(111)/Al2O3(0001) had c-axis orientation and the film on Pt(111)/TiOx/SiO2/Si had no preferred orientation. In addition, it was found that crystallization behavior, orientation and morphology of YMnO3 films on Pt(111)/TiOx/SiO2/Si substrates depended on the annealing condition. The heat-treatment in vacuum at initial stage for crystallization affected the restraint of perovskite phase and formation of hexagonal phase. The following heat-treatment in oxygen promoted the c-axis orientation and grain growth. The optimum annealing procedure for crystallization of the c-axis oriented YMnO3 films on Pt(111)/TiOx/SiO2/Si was addressed.  相似文献   
143.
A high-capacity type of all solid-state battery was developed using sulfur electrode and the thio-LISICON electrolyte. New nano-composite of sulfur and acetylene black (AB) with an average particle size of 1–10 nm was fabricated by gas-phase mixing and showed a reversible capacity of 900 mAh g−1 at a current density of 0.013 mA cm−2.  相似文献   
144.
From the viewpoint of the effective utilization of waste wood, the green composite which is produced by solidifying woodchips has been developed [Miki M, Takakura N, Kanayama K, Yamaguchi K, Iizuka T. Effects of forming conditions on compaction characteristics of wood powders. Trans Jpn Soc Mech Eng C 2003;69(678):502–8 [in Japanese]; Miki M, Takakura N, Kanayama K, Yamaguchi K, Iizuka T. Effects of forming conditions on flow characteristics of wood powders. Trans Jpn Soc Mech Eng C 2003;69(679):766–72 [in Japanese]; Miki M, Takakura N, Iizuka T, Yamaguchi K, Kanayama K. Possibility and problems in injection moulding of wood powders. Trans Jpn Soc Mech Eng C 2004;70(698):2966–72 [in Japanese]]. Since the composite was solidified by the compressive load without the binder, it did not have the high strength and was very brittle, and it had no water resistance [Kinoshita H, Kaizu K, Koga K, Tokunaga H, Ikeda K. In: Proceeding of the Japan Society of Mechanical Engineers M& M2007; 2007. CD [in Japanese]]. In this study, to improve these defects, it was proposed that a biodegradable resin as an adhesive and bamboo fibers as reinforced fibers were applied to the woodchip composite. By using woodchips with two kinds of the particle size, bamboo fibers with three kinds of the length and the biodegradable adhesive, several kinds of specimens changed mixing ratio of those materials were produced by compression molding at the appropriate temperature. By examining the bending strength and impact strength of the composites, it was found that the high bending strength was obtained in the case where woodchips with the small particle size and long bamboo fibers were used, and the high impact strength was obtained in the case where woodchips with the large particle size and long bamboo fibers were used.  相似文献   
145.
All solid-state sheet lithium battery was developed using inorganic solid electrolyte, thio-LISICON (Li3.25Ge0.25P0.75S4), Li–Al anode, and Mo6S8 cathode materials, and the sheet manufacturing process was established. The new sheet-configuration was consisted of the cathode with the grid of current collector, electrolyte sheet with or without mechanical support, and aluminum/lithium composite sheet anode. A sheet battery with a dimension of 30 mm × 30 mm showed good charge–discharge characteristics without any capacity fading at a current of 0.1 mA.  相似文献   
146.
To simplify the labor-intensive conventional routine testing of samples to detect Leuconostoc at a meat processing plant, we developed polymerase chain reaction (PCR) primers specific for Leuconostoc from 16S rRNA gene sequences. These primers did not detect other common lactic acid bacteria such as Lactobacillus plantarum, Lact. sake, Lact. fermentum, Lact. acidophilus and Weissella viridescens. PCR with this primer detected all Leuconostoc species tested (Leu. mesenteroides subsp. mesenteroides, Leu. pseudomesenteroides, Leu. carnosum, Leu. lactic, Leu. citreum, Leu. amelibiosum, Leu. gelidum), except for Leu. fallax, and no other lactic acid bacteria on agarose gel electrophoresis. The method could identify areas contaminated with Leuconostoc in a large-scale industrial meat processing plant. Of 69 samples analyzed, 34 were positive for Leuconostoc according to the conventional culture method (isolation of LAB producing dextran) and PCR, whereas 29 were negative according to both. Six samples were culture-negative but positive by PCR. No false negative results were generated by PCR. The method is rapid and simple, is useful for routinely monitoring areas contaminated with Leuconostoc in meat processing plants, and could help to prevent the spoilage of meat products.  相似文献   
147.
We studied energy transfer between rhodamine B molecules centered in each corn-shaped dendrons that forms self-assembled monolayer (SAM) film on an Au substrate. A SAM film using dendron moiety as a spacer can change the distance between rhodamines depending on the size, so that the energy transfer from an initially photo-excited rhodamine to its surrounding molecules can be controlled. The absorption spectrum of a SAM film for each generation of dendron was measured to ascertain a linear correlation between the generation and the distance. Picosecond time-resolved fluorescence spectra showed clear differences in the fluorescence decay dynamics between third-generation (G3) and fourth-generation (G4) dendron SAM films. In addition, we found that “dry” or “wet” dendron SAM considerably influenced fluorescence behavior. As a result, the use of “wet” G4 SAM is suitable in preserving photo-excitation energy. This is because it gave almost equal dynamics to G4 dendron in the dilute solution and prevented deactivation by energy dissipation.  相似文献   
148.
利用定量金相的方法,研究了固溶-退火条件(温度和时间)对添加0.2%Si的Cu-10Ni-8Sn合金450℃时效时晶界处胞状物的形核与长大的影响.在450℃时效过程中,基体的硬度几乎不受固溶-退火条件的影响.然而,时效过程中固溶-退火条件对胞状物的形核与长大的影响却非常显著.当固溶-退火温度或时间增加时,Si对于胞状沉淀的抑制作用下降.随固溶-退火温度或者时间的增加,淬火态样品中存在于基体晶粒和晶界上的Ni31Si12相颗粒被粗化.因此,可以认为,经较高温度或较长时间固溶-退火的样品时效时,Ni31Si12相颗粒占据胞状物在晶界上的形核位置并抑制胞状物前沿界面迁移的作用降低了.  相似文献   
149.
The Winnipeg Rh Laboratory has reviewed its experiences with maternal CW alloimmunization. From September 24, 1956, to March 31, 1992, 12 women with significant CW alloimmunization underwent 18 pregnancies. In 3 (4 pregnancies) the antibody, despite its strength, was 'naturally occurring' (i.e. there was no known exposure to CW-positive red cells). The remaining 9 women (14 pregnancies) had CW-positive husbands. Two had CW-negative babies and a third infant, probably CW negative, was stillborn and macerated at 43 weeks gestation. Eleven babies were CW positive and had hemolytic disease of the newborn (HDN), with antiglobulin-positive red cells. Five did not require treatment; 2 needed phototherapy only, and 4 (born between 1956 and 1963) required exchange transfusions. No anti-CW screening was carried out until 1977; thereafter it was sporadic, 11 of 51 screening red cells being CW positive in the 39-month period ending March 31st, 1992. From November 1, 1977, to March 31, 1992, 24 women (30 pregnancies, 31 conceptuses) with insignificant anti-CW alloantibodies were identified. Extrapolating these figures to the entire period from September 24, 1956, to March 31, 1992, we estimate that at least 430 women (at least 573 pregnancies) were CW alloimmunized, most of the antibodies being 'naturally occurring'. Only 2% of the conceptuses were CW positive and affected; none were severely affected. Anti-CW is relatively common, occurring in about 1 pregnant Manitoban woman in 1,100. On very rare occasions (11 times in Manitoba in 36 years and 5 months) anti-CW HDN occurs which, although not severe, may end in kernicterus with brain damage or neonatal death unless it is detected promptly and treated appropriately.  相似文献   
150.
To understand formation and deterioration mechanisms of Ta/Ti ohmic contacts that were previously developed for p-GaN, the electrical properties of the Ta/Ti contacts, which were deposited on undoped GaN substrates and subsequently annealed in vacuum (where a slash (/) sign indicates the deposition sequence), were studied. The Ta/Ti contacts displayed good ohmic behavior after annealing at a temperature of 800°C for 10 min in vacuum, although the undoped GaN substrates were used. However, deterioration of the present ohmic contacts was observed during room-temperature storage. These contact properties were similar to those observed in the Ta/Ti contacts prepared on p-GaN. Hall-effect measurements revealed that thin n-type conductive layers were found to form on surfaces of both the undoped GaN and p-GaN substrates after annealing at 800°C in vacuum.  相似文献   
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