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871.
The mycobacterial cell wall is composed of large amounts of lipids with varying moieties. Some mycobacteria species hijack host cells and promote lipid droplet accumulation to build the cellular environment essential for their intracellular survival. Thus, lipids are thought to be important for mycobacteria survival as well as for the invasion, parasitization, and proliferation within host cells. However, their physiological roles have not been fully elucidated. Recent studies have revealed that mycobacteria modulate the peroxisome proliferator-activated receptor (PPAR) signaling and utilize host-derived triacylglycerol (TAG) and cholesterol as both nutrient sources and evasion from the host immune system. In this review, we discuss recent findings that describe the activation of PPARs by mycobacterial infections and their role in determining the fate of bacilli by inducing lipid metabolism, anti-inflammatory function, and autophagy.  相似文献   
872.
Pre-formed polycrystalline Palladium aggregates (ca. 200 nm in diameter) were coated by thin mesoporous silica layers to form metal-mesoporous silica composite materials. To synthesize the composites, Pd aggregates were dispersed in an aqueous solution of C16H33N(CH3)3Br to which tetraethylorthosilicate (TEOS) was then added to give composite precipitates. The surfactant template in the precipitate was subsequently removed by extraction with an acetic acid/ethanol solvent. TEM images of the composite (containing as much as 65 wt% Pd) revealed that the Pd aggregates were fully surrounded by mesoporous silica layers (ca. 50 nm in thickness) having ordered pores that penetrate to large extent from the exterior to the surface of Pd aggregates. When the materials were used as catalysts for cinnamaldehyde hydrogenation in toluene, the reactant molecules were concentrated in the meso channels by a factor of ca. 3. Accordingly, the composites showed comparable or higher activity than that observed for neat Pd aggregates. This study highlights the preparation of unique metal-mesoporous silica composite materials by simple synthetic procedures and which are usable as active Pd catalysts.  相似文献   
873.
In this paper, a rapid and simple method to determine the optimal temperature conditions for denaturant electrophoresis using a temperature-controlled on-chip capillary electrophoresis (CE) device is presented. Since on-chip CE operations including sample loading, injection and separation are carried out just by switching the electric field, we can repeat consecutive run-to-run CE operations on a single on-chip CE device by programming the voltage sequences. By utilizing the high-speed separation and the repeatability of the on-chip CE, a series of electrophoretic operations with different running temperatures can be implemented. Using separations of reaction products of single-stranded DNA (ssDNA) with a peptide nucleic acid (PNA) oligomer, the effectiveness of the presented method to determine the optimal temperature conditions required to discriminate a single-base substitution (SBS) between two different ssDNAs is demonstrated. It is shown that a single run for one temperature condition can be executed within 4 min, and the optimal temperature to discriminate the SBS could be successfully found using the present method.  相似文献   
874.
In a comparison of the German society's official indirect method and the direct LC‐MS method to determine the levels of glycidol fatty acid esters (GEs) in edible oils, the indirect method showed lower GE levels in cases of a high level of GEs and/or containing partial acylglycerols (PGs). The present study used kinetic analysis to compare the scope of both methods. A kinetic model combination of reversible decomposition of GEs and 3‐monochloro‐1,2‐propanediol forming substances (MCPD‐FS) generated from PGs accurately predicted a persistent level of underestimation of commercial vegetable oils when the indirect method was used. The results of the kinetic prediction showed that the underestimation in the indirect method was proportional to the PG and GE levels in oils. Although most conventional cooking oils are low in GEs and PGs, significant error may occur in oils such as palm oil, which are reported to have a higher content of GEs and DAGs. The direct method was affected by neither the GEs nor the PGs, and proved to be a truer and more accurate determinant of GE levels in a wide range of edible oil products.  相似文献   
875.
Novel liquid-crystalline (LC) benzoxazines were synthesized by using 4(4′-heptoxybenzoyloxy)benzylidene-4″-aminophenol, various alkylamines, and formalin in chloroform under reflux. Polarized optical microscopy (POM) and differential scanning calorimetry (DSC) were used to analyze the LC behavior of the synthesized benzoxazines. The novel benzoxazines showed nematic and smectic phases upon cooling cycle from the isotropic liquids. The LC benzoxazines also showed a nematic phase upon heating cycle, indicating that the novel benzoxazines are enantiotropic liquid crystals. The ring-opening polymerization behavior of the LC benzoxazines was investigated by DSC and IR analyses. POM observations showed that a polybenzoxazine film, prepared by thermally curing the LC benzoxazine up to 160 °C for 1 h, exhibited birefringence at room temperature.  相似文献   
876.
A novel Ru π‐expanded terpyridyl sensitizer, referred to as HIS‐2, is prepared based on the molecular design strategy of substitution with a moderately electron‐donating 4‐methylstyryl group onto the terpyridyl ligand. The HIS‐2 dye exhibits a slightly increased metal‐to‐ligand charge transfer (MLCT) absorption at around 600 nm and an intense π–π* absorption in the UV region compared with a black dye. Density functional theory calculations reveal that the lowest unoccupied molecular orbital (LUMO) is distributed over the terpyridine and 4‐methylstyryl moieties, which enhances the light‐harvesting capability and is appropriate for smooth electron injection from the dye to the TiO2 conduction band. The incident photon‐to‐electricity conversion efficiency spectrum of HIS‐2 exhibits better photoresponse compared with black dye over the whole spectral region as a result of the extended π‐conjugation. A DSC device based on black dye gives a short‐circuit current (JSC) of 21.28 mA cm?2, open‐circuit voltage (VOC) of 0.69 V, and fill factor (FF) of 0.72, in an overall conversion efficiency (η) of 10.5%. In contrast, an HIS‐2 based cell gives a higher JSC value of 23.07 mA cm?2 with VOC of 0.68 V, and FF of 0.71, and owing to the higher JSC value of HIS‐2, an improved η value of 11.1% is achieved.  相似文献   
877.
The kinetic characteristics of the column were necessary property to be understood before actual operation. Hence, a functional small-scale zeolite column system was installed for conducting the experiments to understand decontamination behaviors. Each column has a 2 cm inner diameter and a 12 cm height, and 12 g of zeolite-type media was packed into the column. The column experiments were carried out with Kurion-zeolite, herschelite, at different feed rates of simulated water with different concentrations of Cs and sea salt. As expected from equilibrium ion-exchange isotherms obtained for KURION-herschelite, the adsorption of Cs is hampered by the existence of sea salt ratio. The difference in breakthrough behaviors can be ascribed to the difference in sea salt ratio. Above 1000 bed volumes, the adsorption rate of Cs was the same at a solution velocity of between 14 and 81 cm/min. Under the condition of a 3.4 wt% sea salt ratio, the performance of the media supplied by KURION was in the order surfactant modified zeolite < silver-impregnated engineered herschelite = herschelite (H). This result was suggested to evaluate the performance of KURION media on the actual columns.  相似文献   
878.
The Goto-Kakizaki (GK) rat is an animal model for spontaneous-onset, non-obese type 2 diabetes. Despite abundant evidence about disorders in metabolism, little information is available about fatty acid metabolism in the liver of GK rats. This study aimed to investigate the characteristics of the fatty acid profile, particularly MUFA, and the mechanism underlying the alterations in fatty acid profiles in the liver of GK rats. The activities of enzymes that participate in the biosynthesis of MUFA, expressions of genes encoding these enzymes, and the fatty acid profile in the liver were compared with those of obese Zucker (fa/fa) (ZF) rats, which are obese and non-diabetic. Stearoyl-CoA desaturase (SCD) activity and SCD1 gene expression were considerably up-regulated in GK rats, and these levels were largely comparable to those in ZF rats. However, the proportions and contents of oleic acid and palmitoleic acid were very low considering the highly elevated activity of SCD in the liver of GK rats, when compared with ZF rats. Palmitoyl-CoA chain elongation (PCE) activity and fatty acid elongase (Elovl6) gene expression were markedly up-regulated in ZF rats, whereas PCE activity was up-regulated much less and Elovl6 gene expression was unchanged in GK rats. These results suggest the possibility that up-regulation of gene expression of Elovl6 along with SCD1 is indispensable to elevate the proportions and contents of oleic acid in the liver.  相似文献   
879.
本文根据若杉浩一先生与千代田健一先生在上海曹杨路147号艾锐斯办公家具展厅9月16日举办的“办公创新时尚研讨会”上的演讲编辑而成。若杉先生在亚太地区拥有丰富的家具及商务空间成功设计经验,深知理想的工作环境必须回归到合乎人性,他提出的“留一半让使用者参与”,“工作与生活融合”的设计体会.为办公室设计提出了新的参考。  相似文献   
880.
Almost all sake yeasts form a thick foam layer on sake mash during fermentation. To reduce the amount of foam, nonfoaming mutants were bred from foam-forming sake yeasts. To elucidate the mechanism of this foam formation, we have cloned a gene from a foam-forming sake yeast that confers foam-forming ability to a nonfoaming mutant. This gene, named AWA1, encodes a glycosylphosphatidylinositol (GPI) anchor protein that is localized to the cell wall and is required for cell surface hydrophobicity. In this paper, we describe the genomic analysis of the AWA1 gene in a nonfoaming mutant strain K701 derived from a foam-forming sake yeast strain K7. K701-AWA1 was cloned in a cosmid and its sequence was compared with that of K7-AWA1. Although the 5' half of K701-AWA1 was identical to that of K7-AWA1, the 3' half of K701-AWA1 was different from that of K7-AWA1, resulting in a loss of the C-terminal hydrophobic sequence of Awa1p. Since this sequence is considered to be required for the anchoring of Awa1p to the cell wall, K7-Awa1p could not confer both cell surface hydrophobicity and foam-forming ability to strain K701 cells. Since the change found in K701-AWA1 was not a point mutation but a larger scale event, we analyzed chromosome rearrangement by pulsed-field gel electrophoresis Southern blot analyses. The results suggest that the left subtelomeric region of chromosome IX in strain K7 was translocated to the AWA1 gene in chromosome XV by a nonreciprocal recombination.  相似文献   
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