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91.
How can architecture for workspaces be future-proofed? From shifts between favouring open planning or subdivided spaces, to practical demands brought by new technologies and working patterns, firms face a real challenge in adapting to change. Despina Katsikakis advises and lectures internationally on workspace thinking and design. Here she looks at trends in the field over the last few decades, and suggests how businesses might best prepare for future developments – through a loose-fit approach.  相似文献   
92.
93.
In the presence of established atherosclerosis, estrogens are potentially harmful. MMP-2 and MMP-9, their inhibitors (TIMP-2 and TIMP-1), RANK, RANKL, OPG, MCP-1, lysyl oxidase (LOX), PDGF-β, and ADAMTS-4 play critical roles in plaque instability/rupture. We aimed to investigate (i) the effect of estradiol on the expression of the abovementioned molecules in endothelial cells, (ii) which type(s) of estrogen receptors mediate these effects, and (iii) the role of p21 in the estrogen-mediated regulation of the aforementioned factors. Human aortic endothelial cells (HAECs) were cultured with estradiol in the presence or absence of TNF-α. The expression of the aforementioned molecules was assessed by qRT-PCR and ELISA. Zymography was also performed. The experiments were repeated in either ERα- or ERβ-transfected HAECs and after silencing p21. HAECs expressed only the GPR-30 estrogen receptor. Estradiol, at low concentrations, decreased MMP-2 activity by 15-fold, increased LOX expression by 2-fold via GPR-30, and reduced MCP-1 expression by 3.5-fold via ERβ. The overexpression of ERα increased MCP-1 mRNA expression by 2.5-fold. In a low-grade inflammation state, lower concentrations of estradiol induced the mRNA expression of MCP-1 (3.4-fold) and MMP-9 (7.5-fold) and increased the activity of MMP-2 (1.7-fold) via GPR-30. Moreover, p21 silencing resulted in equivocal effects on the expression of the abovementioned molecules. Estradiol induced different effects regarding atherogenic plaque instability through different ERs. The balance of the expression of the various ER subtypes may play an important role in the paradoxical characterization of estrogens as both beneficial and harmful.  相似文献   
94.
从研究大学生失信行为八手,分析失信行为产生的主,客观原因,解析在大学生诚信教育过程中存在的欠缺,并提出要加强诚信教育研究,建立诚信信用档案,防苊大学生失信行为.  相似文献   
95.
As use of handheld multimedia devices has exploded globally, safety experts have begun to consider the impact of distraction while talking, text-messaging, or listening to music on traffic safety. This study was designed to test how talking on the phone, texting, and listening to music may influence pedestrian safety. 138 college students crossed an interactive, semi-immersive virtual pedestrian street. They were randomly assigned to one of four groups: crossing while talking on the phone, crossing while texting, crossing while listening to a personal music device, or crossing while undistracted. Participants distracted by music or texting were more likely to be hit by a vehicle in the virtual pedestrian environment than were undistracted participants. Participants in all three distracted groups were more likely to look away from the street environment (and look toward other places, such as their telephone or music device) than were undistracted participants. Findings were maintained after controlling for demographics, walking frequency, and media use frequency. Distraction from multimedia devices has a small but meaningful impact on college students’ pedestrian safety. Future research should consider the cognitive demands of pedestrian safety, and how those processes may be impacted by distraction. Policymakers might consider ways to protect distracted pedestrians from harm and to reduce the number of individuals crossing streets while distracted.  相似文献   
96.
During the last 15 years, a series of food scares and crises (BSE, dioxin, foot and mouth disease) have seriously undermined public confidence in food producers and operators and their capacity to produce safe food. As a result, food safety has become a top priority of the European legislative authorities and systems of national food control have been tightened up and have included the establishment of the European Food Safety Authority. In Greece a law creating the Hellenic Food Safety Authority has been approved. The main objectives of this Authority are to promote the food security to consumers and inform them of any changes or any development in the food and health sector.

The paper reviews the general structure of the current food control system in Greece. It describes the structure and the mission of the Hellenic Food Safety Authority and explains the strategy to carry out inspections and the analysis of the preliminary results of such inspections. Details are also given of the personnel training and certification and accreditation standards to be met by the Authority by the end of 2004.  相似文献   

97.
Summary Solutions of a whey protein mixture were subjected to various time/temperature treatments, at pH 6.7. Kinetic and thermodynamic activation parameters for the rates of irreversible denaturation/aggregation of the principal whey protein component—β-lactoglobulin (β-lg) were followed by gel permeation. Fast Protein Liquid Chromatography (non-dissociating, non-reducing conditions) and by SDS-PAGE (dissociating, non-reducing conditions). The rate of loss of native β-lg owing to the formation of disulphide linked protein aggregates (ksds-page) and the rate of formation of aggregates via both covalent and non-covalent bonds (kgp-fplc) showed similar biphasic Arrhenius plots. However, the break of the plot occurred at different points. The kgp-fplc values were higher than values of ksds-page for all the temperatures examined. There was a similar trend for the thermodynamic activation parameters implying that not all of the β-lg aggregates through thiol–disulphide interactions. Hydrophobically driven associations occur within the aggregates.  相似文献   
98.
In this paper, the retarding effect of a green additive, citric acid, towards calcium carbonate scale deposition is studied. Scale formation is one of the most common causes of malfunctions in process equipment. This is the reason it is crucial to retard scale precipitation, that is, in order to reduce economic damages. With this additive in the solution, experimental runs have been carried out in supersaturation conditions in terms of concentration of calcium carbonate at equilibrium, with a supersaturation ratio ranging from 16 to 280, at 25°C. Three different concentrations of citric acid have been investigated (0.520 × 10−3, 1.041 × 10−3 and 1.561 × 10−3 M) in a laboratory scale plant. Comparing results obtained in terms of induction time with previous experimental runs, performed without additives, citric acid has shown its significant capacity to retard calcium carbonate precipitation, by increasing induction time values. This behaviour is enhanced by raising the additive concentration in solution up to a specific threshold value, beyond which no benefit in terms of calcium scale inhibition is gained. Furthermore, interfacial tension has been computed without and with citric acid at 0.520 × 10−3 and 1.041 × 10−3 M, as a function of the different concentration amounts investigated. The values obtained are in good agreement with data reported in the literature.  相似文献   
99.
BACKGROUND: A greenhouse experiment was performed to study the effect of cumulative air temperature and photosynthetically active radiation (PAR) on tomato quality. Tomato plants were subjected to two different shading treatments causing a 30 and 50% reduction in incoming PAR respectively (plants were exposed to 70 and 50% of incoming PAR respectively). Control plants (exposed to 100% of incoming PAR) were also included in the experiment. The experiment was carried out under unheated greenhouse conditions. To minimise the dependence of temperature on PAR, only a small area inside a large greenhouse was shaded, thereby allowing air currents to homogenise temperature all over the enclosure. Parameters of tomato quality were correlated with cumulative temperature (Tcum) and cumulative PAR (PARcum) for a period of 45 days before harvest. RESULTS: Tcum was strongly correlated with firmness, electrical conductivity, soluble solids content and total phenolic compounds and weakly correlated with pH, dry weight, titratable acidity and vitamin C content. PARcum was only weakly correlated with firmness, dry weight, soluble solids content and total phenolic compounds. CONCLUSION: Tcum has a stronger influence on tomato quality than PARcum. Growers could obtain tomatoes of similar quality under lower PAR than that provided by natural sunlight. Copyright © 2007 Society of Chemical Industry  相似文献   
100.
The nucleation of two kinds of crystalline nanoparticles, zinc sulfide (ZnS), and cadmium sulfide (CdS), is achieved directly into specific sites of polymer matrices after their irradiation with UV laser pulses. The starting samples consist of polymers doped with precursors of Zn or Cd thiolate that are proved to decompose after the absorption of UV light, resulting into the nanoparticles formation. The growth of the crystalline nanostructures is followed throughout the irradiation of the samples with successive incident pulses, by different methods, such as transmission electron microscopy, atomic force microscopy, confocal microscopy, and X‐ray diffraction. Special attention is paid to the difference of the formation pathways of the two kinds of nanoparticles studied, because the Cd thiolate precursor exhibits much higher absorption efficiency than the Zn thiolate one, at the applied UV wavelength. Indeed, CdS nanoparticles become evident after the very first incident UV pulses, whereas the formation of ZnS nanocrystals requires rather prolonged irradiation, always through a macroscopically nondestructive procedure for the polymer matrix. POLYM. COMPOS., 2010. © 2009 Society of Plastics Engineers  相似文献   
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