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21.
We designed a tabletop brainwriting interface to examine the effects of time pressure and social pressure on the creative performance. After positioning this study with regard to creativity research and human activity in dynamic environments, we present our interface and experiment. Thirty-two participants collaborated (by groups of four) on the tabletop brainwriting task under four conditions of time pressure and two conditions of social pressure. The results show that time pressure increased the quantity of ideas produced and, to some extent, increased the originality of ideas. However, it also deteriorated user experience. Besides, social pressure increased quantity of ideas as well as motivation, but decreased collaboration. We discuss the implications for creativity research and Human–Computer Interaction. Anyhow, our results suggest that the Press factor, operationalized by Time- or Social-pressure, should be considered as a powerful lever to enhance the effectiveness of creative problem solving methods.  相似文献   
22.
Fungal strains were screened for lipase producing activities and 10 strains were classified as good producers. Aspergillus sp., Fusarium sp., and Penicillium sp. exhibited the highest activities when fermented in wheat bran (WB) and soybean bran (SB). No fungal growth was observed using sugarcane bagasse (CB). An experimental design was applied to incorporate CB into the fermentation process for lipase production by Aspergillus sp. and Penicillium sp., and to evaluate the best moisture content for the substrate. Strains studied achieved maximum lipase activities with 25% CB combined with 75% WB or SB at 40% moisture content. The highest lipase activities were observed for WB and SB, and for SB combined with CB using Aspergillus sp. Fermentation of 96 h was the optimum period for enzyme production.  相似文献   
23.
Topiramate, an anticonvulsant medication, is an efficacious treatment for alcohol dependence. To date, little is known about genetic moderators of side effects from topiramate. The objective of this study was to examine 3 single nucleotide polymorphisms (SNPs) of the glutamate receptor GluR5 gene (GRIK1) as predictors of topiramate-induced side effects in the context of a laboratory study of topiramate. Heavy drinkers (n = 51, 19 women and 32 men), 75% of whom met criteria for an alcohol use disorder, completed a 5-week dose escalation schedule to a target dose of either 200 or 300 mg or matched placebo. The combined medication groups were compared with placebo-treated individuals for side effects at target dose. Analyses revealed that an SNP in intron 9 of the GRIK1 gene (rs2832407) was associated with the severity of topiramate-induced side effects and with serum levels of topiramate. Genes underlying glutamatergic neurotransmission, such as the GRIK1 gene, may help predict heterogeneity in topiramate-induced side effects. Future studies in larger samples are needed to more fully establish these preliminary findings. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
24.
This work aimed to optimize the extraction of an extracellular protease produced by the cold-adapted yeast Rhodotorula mucilaginosa L7 using aqueous two-phase systems (ATPS) comprising polyethylene glycol (PEG) and sodium citrate or sodium tartrate. First, the biocompatibility of the phase forming agents was assessed. The results obtained with PEG-2000, PEG-4000, and PEG-6000 demonstrated that even at large PEG concentrations (32 wt%) the protease maintains its activity after 3 h of reaction, whereas an increase in salt concentration provokes a gradual decrease in protease stability. Subsequently, the partitioning of the protease in both types of ATPS was assessed, evaluating the effect of temperature, molecular weight, and concentration of PEG on protease purification, using two 23-full factorial designs. The best partitioning conditions were obtained in PEG-6000/sodium tartrate-based ATPS, at 30ºC (with a yield of 81.09 ± 0.66% and a purification factor of 2.51 ± 0.03). Thus, considering the biodegradable characteristics of the system, the PEG/sodium tartrate ATPS is a viable and economic low-resolution step in protease purification, with a strong potential for future industrial application.  相似文献   
25.
Poly(imide-amide)s (PIAs) were synthesized from isophthalic acids, which have in position 5 a bulky group like 1,8-naphthalimidyl bonded to amino acids as flexible spacers, and the diamine bis(4-aminophenyl)diphenylsilane, which provides a polar group in the main chain. Glycine, l-alanine, l-phenylalanine, l-valine and p-aminobenzoic acid were used as amino acids. Polymers were obtained according to the Yamazaki method and characterized by elemental analysis, optical activity, IR and 1H, 13C and 29Si NMR spectroscopy. PIAs were soluble in aprotic polar solvents but not in common organic solvents, and obtained with low η inh values, which was an indicative of low molecular weights species, probably of oligomeric nature. According to the polymeric structure, the only difference between PIAs is the structure of the amino acid residue, and in this sense it was possible to see an increase of the T g values when the volume of the amino acid residue also increased, due to the lower possibility of internal mobility of the side chains. The higher Tg value was obtained with the PIA-e, which includes an aromatic ring as a side chain, derived from p-aminobenzoic acid. PIAs, in spite of the good TDT values obtained, were not thermally stable in the sense that the 10 % of weight lost was obtained at lower temperature than 400 °C, with the exception of PIA-e derived from p-aminobenzoic acid. However, there was an increase of the TDT values when the volume of the amino acid residue increases. The PIAs do not show good UV–vis transparence probably due to the low free volume of those including an aliphatic amino acid residue.  相似文献   
26.
This study focuses on the behavior of sodium dioctylsulfosuccinate (SDOSS) in 50/50 w/w % polystyrene/poly(butyl acrylate) (p-Sty/p-BA) latex films. Specifically, mobility and orientation are examined in the context of the film formation by the use of dynamic mechanical thermal analysis and attenuated total reflectance (ATR) Fourier transform infrared (FT-IR) spectroscopy. While for the homopolymer blends of p-Sty and p-BA, two Tg values resulting from a phase separation of p-Sty and p-BA phases are observed, only a single Tg is detected for a copolymer of the same mixture, indicating a single phase within the film. ATR FTIR spectroscopic data indicate that the phase separation of p-Sty and p-BA blends does not occur uniformly across the film. After coalescence, p-Sty particles produce a significant degree of stratification at approximately 1.6 μm from the film surface. At this depth, the polystyrene rings assume preferentially parallel orientation to the film surface. At the same time, the hydrophilic groups of SDOSS surfactant (SO3Na+) are oriented preferentiallyparallel to the surface. Under high relative humidity conditions, water is able to diffuse into the film and swells the surface layers, thus causing them to expand. As a result, the top, predominately poly-n-BA surface becomes “thicker», and p-Sty phase appears to be near 2.3 μm from the surface. The polystyrene rings maintain their preferential parallel orientation to the surface, but the hydrophilic groups of SDOSS are able to diffuse into the film with the water uptake and are thus not present at the filmair interface. © 1996 John Wiley & Sons, Inc.  相似文献   
27.
The Novel Organic Cation Transporter, OCTN1, is the first member of the OCTN subfamily; it belongs to the wider Solute Carrier family SLC22, which counts many members including cation and anion organic transporters. The tertiary structure has not been resolved for any cation organic transporter. The functional role of OCNT1 is still not well assessed despite the many functional studies so far conducted. The lack of a definitive identification of OCTN1 function can be attributed to the different experimental systems and methodologies adopted for studying each of the proposed ligands. Apart from the contradictory data, the international scientific community agrees on a role of OCTN1 in protecting cells and tissues from oxidative and/or inflammatory damage. Moreover, the involvement of this transporter in drug interactions and delivery has been well clarified, even though the exact profile of the transported/interacting molecules is still somehow confusing. Therefore, OCTN1 continues to be a hot topic in terms of its functional role and structure. This review focuses on the most recent advances on OCTN1 in terms of functional aspects, physiological roles, substrate specificity, drug interactions, tissue expression, and relationships with pathology.  相似文献   
28.
29.
In silico comparison of 34 putative pks genes in Aspergillus niger strain CBS 513.88 versus A. niger strain ATCC 1015 genome revealed significant nucleotide identity (>95% covering a minimum of 99% of the gene sequence) for 31 of these genes (approximately 91%). A. niger CBS 513.88 harbors three putative pks genes (An01g01130, An11g05940, and An15g07920), for which nucleotide identity was not found in A. niger ATCC 1015. To compare the results of the in silico analysis with the in vivo situation, experimental data were obtained for a large number of A. niger strains obtained from different substrates and geographical regions. Three putative pks genes that were found to be variable between the two A. niger strains using bioinformatics tools were in fact strain-specific genes based on experimental data. The PCR amplification signals for the An01g01130, An11g05940, and An15g07920 pks genes were detected in only 97%, 71%, and 26% of the strains, respectively. Southern blot analyses confirmed the PCR data. Because one of the strain-specific pks genes (An15g07920) is located in a putative ochratoxin cluster, we focused our investigation on that region. We assessed the ochratoxin production capability of the 119 A. niger strains and found a positive association between the presence of this pks gene and the capability of the respective strain to produce ochratoxin.  相似文献   
30.
The effect of ultraviolet processing (10.6 and 63.7 kJ m(-2)) on selected properties of egg white (absorbance, particle size, protein fractions, free sulfhydryl content, immunoreactivity, viscosity, gelling and foaming properties) was investigated. Ultraviolet exposure induced the development of browning, the formation of large protein aggregates by disulfide exchange, and protein backbone cleavage. However, egg white proteins were differently sensitive to UV radiation. No changes in immunoreactivity, gelling temperature and gel firmness were observed. Independently on the UV dose, light treated egg white produced foams with higher stability. This effect was attributed to protein aggregates jamming in the fluid interstices between bubbles and/or to the higher viscosity of the aqueous phase. The latter was also associated to higher foam volume.  相似文献   
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