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排序方式: 共有4188条查询结果,搜索用时 15 毫秒
1.
Scientometrics - U.S. university engagement with Africa in various areas including global health, education, environment, and agriculture has grown in the last 15 years. However, there is... 相似文献
2.
In a study of conversion from CH4 to H2, jet flame characteristics of these gases and their blends are compared on a burner diameter scale of mm. Low velocity H2 and CH4 jets, burned on pipes of different diameters, indicate higher blow-off limits for H2, but lower heat release rates, a consequence of its lower specific energy. Compensation for this might be obtained through increased H2 flow velocity, or a small increase in pipe diameter. Blended CH4/H2 flames have lower heat release rates than CH4 alone, yet small proportions of H2, with CH4 might still be burned, on a CH4 burner. Throughout, fundamental understanding is enhanced through two dimensionless groups: laminar flame thickness normalised by burner diameter, δk/D, and the dimensionless flow number, U1. These suggest an optimal role for H2 combustion, utilizing its high acoustic and blow-off velocities, in high intensity, subsonic, combustors, at low δk/D, and high U1. 相似文献
4.
Bradley J. Smith Brandon S. Harris Tyler J. Harris Lisa A. LaBudde Cari-Ann Hayer 《Journal of Great Lakes research》2018,44(4):798-804
The Asian clam Corbicula fluminea is among the most prolific aquatic invaders in the world; but in colder mid-latitude areas, like the Laurentian Great Lakes, their population expansion has likely been limited by poor overwinter survival. In these areas, Asian clams are typically found in thermal refugia like warmwater discharges from industrial facilities. We sought to identify the current extent of Asian clam populations in Lake Michigan and waters immediately adjacent to it, specifically at locations most likely to harbor overwintering populations – industrial warmwater discharges. During April–May 2017, we surveyed 17 locations around Lake Michigan. Evidence of Asian clam populations was found at four sites, though live specimens (n?=?3) were only found at the Indiana Harbor Ship Canal in East Chicago, IN. Shells or fragments of shells were found at Green Bay, WI, Waukegan, IL, and Port Sheldon, MI. Our findings indicate that although Asian clams are present in Lake Michigan, they are relatively rare, and remain isolated to a few small pockets of over-wintering habitat. 相似文献
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6.
This paper investigates the idea of cultivated wildness at the intersection of landscape design and artificial intelligence. The paper posits that contemporary landscape practices should overcome the potentially single understanding on wilderness, and instead explore landscape strategies to cultivate new forms of wild places via ideas and concerns in contemporary Environmental Humanities, Science and Technology Studies, Ecological Sciences, and Landscape Architecture. Drawing cases in environmental engineering, computer science, and landscape architecture research, this paper explores a framework to construct wild places with intelligent machines. In this framework, machines are not understood a layer of “digital infrastructure” that is used to extent localized human intelligence and agency. Rather machines are conceptualized as active agents who can participate in the intelligence of co-production. Recent developments in cybernetic technologies such as sensing networks, artificial intelligence, and cyberphysical systems can also contribute to establishing the framework. At the heart of this framework is “technodiversity,” in parallel with biodiversity, since a singular vision on technological development driven by optimization and efficiency reinforces a monocultural approach that eliminates other possible relationships to construct with the environment. Thus, cultivated wildness is also about recognizing “wildness” in machines. 相似文献
7.
Quintin Bradley 《Housing Studies》2020,35(2):333-352
AbstractThe aim of this article is to reclaim the democratic legitimacy of self-selecting and informed publics in citizen engagement in housing development planning. It argues for an approach to public participation in which the issues, and the articulation of conflicting attachments to those issues, are understood as the occasion for democratic politics. The article illustrates this approach in an analysis of the use of direct democracy to decide housing allocations in the policy of neighbourhood planning in England. Drawing on literature from Science and Technology Studies and actor–network theory, it evidences the public articulation of house-building as a matter of concern and identifies the agency of housing in enrolling publics, translating interests and in fostering debate and contention. It concludes that the articulation of conflicting interests can deepen democratic engagement in housing development planning and open up the exclusions through which this issue is currently framed. 相似文献
8.
Iron oxide amended biosand filters for virus removal 总被引:1,自引:0,他引:1
Laboratory studies were performed to determine if the addition of iron oxides throughout biosand filter (BSF) media would increase virus removal due to adsorption. The proposed mechanism is electrostatic adsorption of negatively charged virion particles to positively charged iron oxides formed during the corrosion of zerovalent iron. Initial tests conducted using continuous flow, small-scale glass columns showed high MS2 bacteriophage removal in an iron-amended sand column (5log10) compared to a sand-only column (0.5log10) over 20 pore volumes. Additionally, two experiments with a column containing iron particles revealed 4log10 and 5log10 removal of rotavirus in the presence of 20 mg/L total organic carbon. Full-scale BSFs with iron particles removed >4log10 MS2 for the duration of the experiment (287 days), while BSF with steel wool removed >4log10 MS2 for the first 160 days. Plug flow for the BSF was shown to depend on uniformity between the iron oxide material and sand media grains. The results suggest that the duration of effective virus removal by iron-amended biosand filtration depends on source water conditions and the quantity and composition of iron material added. Overall, this study provides evidence that iron-amended BSFs may advance the field of point-of-use technologies and bring relief to millions of people suffering from waterborne diseases. 相似文献
9.
Helen Clare Lingard Keith Townsend Lisa Bradley Kerry Brown 《Construction Management & Economics》2013,31(10):1101-1112
Project‐based construction workers in the Australian construction industry work long and irregular hours and experience higher levels of work‐to‐family conflict and burnout than office‐based workers, giving rise to an interest in alternative work schedules as a means of supporting work–life balance. Alternative work schedules were implemented in four case study construction projects in Australia. Interventions differed between projects, with two implementing a compressed work week, and the others introducing reduced hours schedules (one of which was optional). Data were collected from each case study project, using various combinations of focus groups, surveys, interviews and daily diary collection methods. The results were mixed. The compressed work week appears to have been favourably received where it was introduced. However, waged workers still expressed concerns about the impact on their weekly ‘take‐home’ pay. Attempts to reduce work hours by changing from a six‐ to a five‐day schedule (without extending the length of the working day between Monday and Friday) were less favourably received. Waged workers, in particular, did not favour reduced hours schedules. The results confirm the existence of two distinct labour markets operating in the Australian construction industry and markedly different responses to alternative work schedules, based upon whether workers are waged or salaried. The results clearly show that attempts to improve work–life balance must take the structural characteristics of the industry's labour markets into consideration in the design of interventions. The impact of alternative work schedules is likely to be moderated by institutional working time regimes within the construction industry. 相似文献
10.
Zhuyun Li Cory M. Dungan Bradley Carrier Todd C. Rideout David L. Williamson 《Lipids》2014,49(12):1193-1201
The mammalian target of rapamycin (mTOR) signaling pathway is hyperactive in liver, adipose and skeletal muscle tissues of obese rodents. Alpha‐lipoic acid (αLA) has been well accepted as a weight‐loss treatment, though there are limited studies on its effect on mTOR signaling in high‐fat fed, obese rodents. Therefore, the goal of this study was to determine mTOR signaling and oxidative protein alterations in skeletal muscle of high‐fat fed, obese rats after αLA supplementation. Phosphorylation of the mTOR substrate, eukaryotic initiation factor (eIF) 4E‐binding protein 1 (4E‐BP1) and eIF4B were significantly reduced (p < 0.05) in muscle from αLA supplemented rats. Activation of AMP‐activated protein kinase (AMPK), an mTOR inhibitory kinase, was higher (p < 0.05) in the αLA group. Protein expression of markers of oxidative metabolism, acetyl CoA carboxylase (ACC), cytochrome c oxidase IV (COX IV), peroxisome proliferator‐activated receptor (PPAR), and PPAR gamma coactivator 1‐alpha (PGC‐1α) were significantly higher (p < 0.05) after αLA supplementation compared to non‐supplemented group. Our findings show that αLA supplementation limits the negative ramifications of consuming a high fat diet on skeletal muscle markers of oxidative metabolism and mTORC1 signaling. 相似文献