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High-temperature co-electrolysis shows comparable performance to steam electrolysis. Current densities above 1 A cm−2 can be reached between 700 °C and 800 °C. Tailor-made syngas is produced, mainly determined by the reactant ratio. The experimental results are supported by modeling. Durability tests with cathode-supported cells show increased voltage degradation rates during electrolysis compared to fuel cell operation. Nickel depletion is found to be the main cause.  相似文献   
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Hairdressers are exposed to particulate matter (PM), a known air pollutant linked to adverse health effects. Still, studies on occupational PM exposures in hair salons are sparse. We characterized indoor air PM concentrations in three salons primarily serving an African/African American (AA) clientele, and three Dominican salons primarily serving a Latino clientele. We also assessed the performance of low-cost sensors (uRAD, Flow, AirVisual) by comparing them to high-end sensors (DustTrak) to conduct air monitoring in each salon over 3 days to quantify work shift concentrations of PM2.5, respirable PM (RPM), and PM10. We observed high spatial and temporal variability in 30-min time-weighted average (TWA) RPM concentrations (0.18–5518 μg/m3). Readings for the uRAD and AirVisual sensors were highly correlated with the DustTrak (R2 = 0.90–0.99). RPM 8-hour TWAs ranged from 18 to 383 µg/m3 for AA salons, and 9–2115 µg/m3 for Dominican salons. Upper 95th percentiles of daily RPM exposures ranged from 439 to 2669 µg/m3. The overall range of 30-min TWA PM2.5 and PM10 concentrations was 0.13–5497 and 0.36-,541 μg/m3, respectively. Findings suggest that hairdressers could be overexposed to RPM during an 8-hour shift. Additional comprehensive monitoring studies are warranted to further characterize temporal and spatial variability of PM exposures in this understudied occupational population.  相似文献   
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境外建筑师事务所如何适应当前国内的建筑潮流并在其中有所作为?除了在方案竞赛中能展现具有“视觉震撼性”的透视效果图外,还要具备一套行之有效的设计管理系统。主要包括三方面内容:1.团队精神,2.各专业之间的协调,3.阶段性设计质量的保证。文章将就这三个内容展开讨论。  相似文献   
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ABSTRACT

This paper examines the issue of assessing the value of social design research. It locates the emergence of social design practice and research against a background in which public and social organisations are increasingly bureaucratised as a result of New Public Management and shifts to New Public Governance. Within universities, too, organisational processes and structures require research to demonstrate impact within an audit culture. Through the study presented in this paper, we claim that the bureaucracies found in contemporary academia are ill-equipped to adequately assess generative, impactful, and multi-sited research in which value is co-produced with diverse participants. This presents challenges when attempting to understand the value of social design research. Building on social research and studies of innovation policy, sustainable human-computer interaction and evaluation, we define social design research as inventive, contingent, and political. To address the issue of its evaluation, we propose two-stage social design research. In the first stage, research issues, questions, methods, data, and ‘proto-publics’ are assembled, which reveal the conflicting framings and ways that value is assessed. These are re-assembled in a second stage during which the research is stabilised. The findings have implications for research managers, academics and their partners, and university administrators.  相似文献   
6.
There is extensive research on the negative health impacts of poor housing quality. However, little is known about the potential health benefits of high-quality housing in poor neighbourhoods. Neighbourhoods with unexpectedly good health outcomes despite high levels of deprivation have been deemed resilient places and housing quality in these areas may be a contributor to this resilience. This study aimed to evaluate whether an indicator of neighbourhood housing quality was associated with a previously quantified resilience index (RINZ) in New Zealand. It was found that areas with high housing quality tended to have higher median income, greater proportions of partnered people and shorter-term residents, and very low proportions of Māori. A positive association was found between housing quality and resilience, after adjustment for deprivation. There was no indication of differences by heterogeneity in housing quality within the aggregate unit of analysis. These findings pose the hypothesis that improving housing quality in similarly deprived areas that have poor health outcomes could potentially boost health. To extend this understanding, further development of a more sophisticated housing quality indicator is recommended.  相似文献   
7.
Following a catalogue of problems in British farming, attempts are being made to re-localize agriculture for reasons of rural regeneration and sustainable development. It is a move that is both consumer driven and encouraged by government policies and grant schemes. This article examines what the implications for the land use planning system might be from this small revolution in farming and retailing. Research in Somerset using planning history records reveals that in some cases planning permission has proved an obstacle to the establishment and expansion of local food businesses. This is especially so for applications for farm shops and agricultural workers' dwellings. Survey data shows that a significant proportion of local food producers selling through box schemes, farmers' markets and farm gate sales are new entrants to farming. New entrants present particular difficulties for planners and planning committees, because they challenge the conventional conception of what farmers and farm businesses are like, and invoke concerns about abuse of the agricultural dwelling concessions provided by the system. A tension is identified between the interpretation of ‘sustainable development’ in planning circles and among local food proponents. The neglect of ‘food miles’ as a consideration in retail planning policy is highlighted as an example of this clash of perspectives.  相似文献   
8.
This paper examines the role of public art in urban redevelopment, focusing on the reconstruction of Coventry (UK) in the post-war years. Overseen by the city's Chief Architect, Donald Gibson, this redevelopment has often been described as resulting in a placeless and artless urban landscape indistinguishable from other redeveloped city centres in post-war Britain. To the contrary, here it is suggested that public art was an important feature of Coventry's new urban landscape, with the attempt to create a new civic identity manifest in a series of highly symbolic and distinctive public artworks. Analysing both the official symbolism of these artworks and their reception in the public sphere, it is concluded that, although just one aspect of the urban landscape, the production and consumption of public art encapsulated the tensions that existed between different visions of the city.  相似文献   
9.
The results of an investigation on the Er doping of porous silicon are presented. Electrochemical impedance spectroscopy, optical reflectivity, and spatially resolved energy dispersive spectroscopy (EDS) coupled to scanning electron microscopy measurements were used to investigate on the transient during the first stages of constant current Er doping. Depending on the applied current intensity, the voltage transient displays two very different behaviors, signature of two different chemical processes. The measurements show that, for equal transferred charge and identical porous silicon (PSi) layers, the applied current intensity also influences the final Er content. An interpretative model is proposed in order to describe the two distinct chemical processes. The results can be useful for a better control over the doping process.

PACS

81.05.Rm; 82.45.Rr  相似文献   
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