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1.
In the current study, the authors used an immediate repetition paradigm with pictures to observe whether repetition enhances word production in bilinguals. In Experiment 1, participants were asked to name pictures that were named previously in the same language (Spanish-Spanish or English-English) or in the opposite language (Spanish-English or English-Spanish). Results revealed a repetition effect both within languages and between languages. Furthermore, there was an asymmetry within language, with repetition priming being larger in Spanish than in English. Experiments 2 and 3 revealed that lag interacted with language for both within- and between-language priming. However, lag resulted in a decrease in the asymmetry for within- but not between-language priming. The results are consistent with the view that within- and between-language repetition priming are mediated by different mechanisms. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
2.
The KlLYS2 gene, encoding the alpha-aminoadipate reductase of Kluyveromyces lactis, was isolated by complementation of a lysA1 mutant. The deduced amino acid sequence shared an identity of 73% with the LYS2 product of Saccharomyces cerevisiae. Despite the high sequence homology of the alpha-aminoadipate reductase genes, the two yeast species differently responded to the presence of alpha-aminoadipate in the medium. Wild-type S. cerevisiae is known to be sensitive to alpha-aminoadipate, but becomes resistant when mutated to lys2. In contrast, K. lactis strains were found to be naturally resistant to alpha-aminoadipate. Therefore, the positive selection procedure for the isolation of lys2 mutants on alpha-aminoadipate, as practised in S. cerevisiae, cannot be applied to K. lactis. A possible reason of this difference may be that the catalytic rate of the alpha-aminoadipate reductase differs in the two yeasts. The EMBL/Genbank Accession No. for the KlLYS2 gene is AJ504405.  相似文献   
3.
In this paper, the synthesis, design, and implementation of a programmable phase shifter circuit for sinusoidal signals is presented. The proposed circuit, built-up herein with operational amplifiers (OPAMPs), high precision resistors and low voltage switches, consists of a digitally controlled amplitude attenuator in combination with a single-tone orthogonalizer. Experimental results agree with theoretical background: the attained phase range was 252° in 256 steps with a median step of 0.9°. The inaccuracy of the circuit was determined to be of 0.03 %. Contrary to other OPAMP approaches for sinusoidal signals reported in the literature and based on a first-order all-pass filter structure, the approximation suggested in this work is based on a different concept. The achieved results demonstrate the functionality of the system for the case of a sinusoidal signal with frequency of 1 kHz. Notwithstanding, the proposed architecture can be extended to operate at higher frequencies by using different building blocks with larger bandwidth. Furthermore, it can be extended as well to work out with other periodic input waveforms, like triangular shapes or square waves, with the use of an appropriate orthogonalizer.  相似文献   
4.
Based on our previous work on the green preparation of Ag–TiO2 photocatalyst with bactericidal activity under visible light, we extended our studies to the synthesis of TiO2–Fe3+ materials with enhanced photocatalytic activity for the degradation of recalcitrant organic pollutants in water. TiO2–Fe3+ nanopowders were synthesized using a robust, environmentally friendly procedure. Established amounts of Fe(NO3)3·9H2O and titanium tetraisopropoxide (TTIP) were mixed using glacial acetic acid as solvent. Hydrolysis of TTIP–Fe3+ was accomplished using a 30 % (W/V) Arabic gum aqueous solution. TiO2–Fe3+ nanopowders were obtained by thermal treatment at 400 °C. In order to elucidate the structure of these photocatalysts, microscopic and spectroscopic characterization techniques were applied. The high resolution transmission electron microscopy (HRTEM) analysis indicated the presence of uniformly distributed particles with average particle size of about 9 nm. According to the HRTEM lattice fringes, ring pattern, and selected area electron diffraction pattern, the crystalline part of the samples consists of anatase (PDF 01-086-1157 with the lattice constant of 3.7852, 9.5139 Å and 90°) as dominant phase. X-ray photoelectron spectroscopy (XPS) was applied to determine the oxidation state of iron. The XPS provides evidence for Fe3+ surface species in the TiO2–Fe3+ composite. Complete degradation of aqueous solutions (20 ppm) of methylene blue and/or methyl orange was accomplished after 4 h of treatment using 150 mg of TiO2–Fe3+/150 mL of dye solution. The in vitro toxicity of the materials was tested. The materials showed no toxicity against human red blood cells.  相似文献   
5.
Sepsis causes high rates of morbidity and mortality in NICUs. The estimated incidence varies between 5 and 170 per 1000 births, depending on the social context. In very low birth-weight neonates, the level of mortality increases with the duration of hospitalization, reaching 36% among infants aged 8–14 days and 52% among infants aged 15–28 days. Early diagnosis is the only tool to improve the poor prognosis of neonatal sepsis. Blood culture, the gold standard for diagnosis, is time-consuming and poorly sensitive. C-reactive protein and procalcitonin, currently used as sepsis biomarkers, are influenced by several maternal and fetal pro-inflammatory conditions in the perinatal age. Presepsin is the N-terminal fragment of soluble CD14 subtype (sCD14-ST): it is released in the bloodstream by monocytes and macrophages, in response to bacterial invasion. Presepsin seems to be a new, promising biomarker for the early diagnosis of sepsis in neonates as it is not modified by perinatal confounding inflammatory factors. The aim of the present review is to collect current knowledge about the role of presepsin in critically ill neonates.  相似文献   
6.
This article analyses a representative selection of photographs from the Archivo General de la Nación Argentina produced by an army of photographers who assiduously chronicled Eva and Juan Domingo Perón’s public engagements. These images were shrewdly informed by an array of popular forms (tango lyrics, the storylines of photo–romances, movies, and radio serials), and by a set of visual models borrowed from the nineteenth-century photography tradition, commercial photography studios of celebrities, Hollywood fashion codes, Soviet-related paradigms anchored in the legacy of the socialist and anarchist movements of early twentieth-century Argentina, and from royal and religious iconography. Through their careful staging before the camera, Perón and Eva amalgamated these visual traditions with their political content in order to reach and unify the multiple socio-political constituencies of Argentina at the time. The conventional aesthetic – in terms of view angles, lighting, and composition – of such images granted their movement a patina of legitimacy and the sense of an enduring legacy.  相似文献   
7.
The synthesis of 3-hetaryl substituted coumarin derivatives [7-hydroxy-2H-chromen-2-on and 9-hydroxy-2H-benzo(f)chromen-2-on] containing a hydroxyl group by reacting 2,4-dihydroxybenzaldehyde and 2,4-dihydroxynaphtaldehydes with 2-cyanomethylbenzothiazole, 2-cyanomethylbenzimidazole, 1-methyl-2-cyanomethylbenzimidazole and 2-cyanomethyl-4-phenylthiazole is presented. The absorption and steady-state fluorescence characteristics of the synthesised 3-hetaryl substituted 7-hydroxy-2H-chromen-2-on and 9-hydroxy-2H-benzo(f)chromen-2-on in a solution of ethanol and at different pH values are studied to assess their possible application as fluorescent probes for use in molecular biology and medicine.  相似文献   
8.
Aguamiel is a beverage produced by some Agave species that is consumed in its fresh or fermented form. Despite its uses and popularity, seasonal effects on its microbial and chemical profiles are unknown. In this study, using aguamiel collected from A. salmiana and A. atrovirens during different seasons, we identified microorganisms by sequencing the 16S and 18S rDNA genes and determined their chemical profiles. In total, 49 microbial strains were identified (38 bacteria and 11 yeasts). The highest richness and biodiversity were observed during winter and summer. Different lactic acid bacteria and yeast genera with potential industrial applications were identified, such as Acetobacter, Lactobacillus, Leuconostoc, and Clavispora. The analysis of the chemical profiles indicated the presence of maltooligosaccharides and fructooligosaccharides, which are associated with human health improvements, during spring in Agave aguamiel. Aguamiel can be used in the food industry due to its microbiological and chemical profiles.  相似文献   
9.
The potential use of the liquid product obtained from the pyrolysis of polystyrene as a raw material for the reproduction of the polymer was investigated in this study. Catalytic and non‐catalytic pyrolysis experiments were carried out in a fixed bed reactor using either model polymer or commercial waste products as the feedstock. The liquid fraction produced from all the pyrolysis experiments consisted mainly of the styrene monomer and this was subjected to re‐polymerization without any further purification, in a DSC with AIBN initiator. It was found that the pyrolysis oil fraction could be re‐polymerized to again produce polymer. However, aromatic compounds included in this fraction may act as chain transfer agents, resulting in alterations in the shape of the reaction rate curve and lowering significantly the average molecular weight and the Tg of the polymer produced.

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10.
A ruthenium(II) complex with bis(3,5-dimethylpyrazol-1-yl)dithioacetate was self-assembled layer-by-layer on silver and gold surfaces. The two-step process and the ability of the complex to scavenge nitric oxide were studied by cyclic voltammetry.  相似文献   
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