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101.
The present study was performed to investigate the age-dependent changes in body composition and the possible role of growth hormone (GH), insulin-like growth factor (IGF)-I and IGF-binding protein-3 (IGFBP-3) in these changes in postmenopausal Japanese women. A total of 161 Japanese women aged 45-88 years (mean 62) were enrolled in the cross-sectional study. Body composition (bone mineral content (BMC), lean body mass (LBM) and fat) was measured by dual-energy X-ray absorptiometry, and the percentage of BMC, LBM and fat was calculated by dividing each absolute value of body composition by total body mass. Urinary GH concentration divided by creatinine in nocturnal urine samples collected just after waking was used as an index of endogenous GH secretion. Serum levels of IGF-I and IGFBP-3 were measured by RIA. Urinary GH levels as well as serum levels of IGF-I and IGFBP-3 declined with age. BMC, %BMC and LBM also declined with age, while fat mass and %fat did not obviously change with age. Urinary GH levels as well as serum levels of IGF-I and IGFBP-3 correlated positively with BMC, even if age was taken into account. On the other hand, urinary GH correlated negatively with fat and %fat. In contrast, serum levels of IGF-I and IGFBP-3 correlated positively with fat and %fat. LBM did not correlate with either urinary GH or serum IGFBP-3 levels but exhibited a weakly positive correlation with serum IGF-I level. The present study suggests that the GH-IGF-I-IGFBP-3 axis positively regulates bone mass, and that GH and IGF-I-IGFBP-3 inversely regulate fat mass, i.e. GH negatively and IGF-I-IGFBP-3 positively regulates it.  相似文献   
102.
Immunoglobulin E (IgE) has been shown to play a critical role in the allergic late-phase reaction, which is marked by intense leukocyte infiltration and edema. In this study we assessed the allergic pleural inflammation triggered by intrapleural (i.pl.) challenge in sensitized rats. We examined pleural effluent from actively sensitized rats following anti-IgE monoclonal antibody (mAb) (MARE-1) provocation for protein exudation, neutrophil as well as eosinophil accumulation. Inflammatory changes triggered by antigen after passive sensitization with IgE mAb was also assessed for comparison. Total serum level of IgE was found to be about threefold increased 7-8 days post-active sensitization, remaining augmented for at least 30 days. Increased levels of peritoneal leukocyte-bound IgE and serum IgE with specificity to ovalbumin were also detected. Nevertheless, the anti-IgE challenge in 14-day actively sensitized was shown to be a weak stimulus of neutrophil and eosinophil accumulation, despite being able to cause intense protein extravasation. Similarly, antigen challenge of IgE-passively sensitized rats caused protein leakage that was comparable to that induced by anti-IgE mAb in actively sensitized rats but led to a much lower neutrophil/eosinophil infiltration. Also, blockade of complement with recombinant human soluble C receptor-1 (sCR1) treatment prevented actively sensitized rats from reacting to antigen with neutrophil and eosinophil recruitment without modifying protein extravasation. These data suggest that IgE and complement-mediated mechanisms probably account for the exudation and leukocyte infiltration that is characteristic of the pleural inflammatory response observed in actively sensitized rats.  相似文献   
103.
Multiple view rendering is a common problem for applications where multiple users visualize a common dataset, as in multi-player games and collaborative engineering tools. For a system to be able to render a large number of views at interactive rates efficiently, parallel processing is an attractive technique. In this work, we present the implementation of a pipelined multiview light field renderer using a cluster with GPUs and MPI. We discuss the parallelization model and the problem of partitioning the tasks of the pipeline among the cluster machines based on the pipeline model and the costs of the stages. Our solution achieves 83% efficiency with ten machines, against only 11% efficiency of a naive parallelization.  相似文献   
104.
OBJECTIVES: To assess the effect of undertaking custodial care of a grandchild on grandparents' depression levels and to determine what characteristics are associated with higher depression levels among caregiving grandparents. DESIGN: A longitudinal national probability panel study: the National Survey of Families and Households. The first wave of data (n= 13 008) was collected in 1987 and 1988, and the second wave of data (n=10008) was collected from 1992 through 1994. SETTING: The survey was conducted in respondents' households in the coterminous United States. PARTICIPANTS: The subsample for this study was composed of 3111 respondents who reported being grandparents during the 1992-1994 interviews and for whom complete depression information was available. Of these grandparents, 158 were the primary caregivers for their grandchildren in the 1990s. MAIN OUTCOME MEASURES: Depression was measured using a modified version of the Center for Epidemiological Studies Depression Scale. RESULTS: Those who provide primary care for a grandchild are almost twice as likely to have levels of depressive symptoms above the traditional Center for Epidemiological Studies Depression Scale cut point of 16 (25.1% vs 14.5%). Even when controlling for baseline depression and demographic variables known to affect depressive symptoms, undertaking the care of a grandchild was associated significantly with higher depression levels in a multivariate prospective analysis (P<.01). Among caregiving grandparents, those who recently assumed caregiving responsibilities (P<.05) and women (P<.10) were more depressed and older respondents (P<.10) and those in good health (P<.001) were less depressed. CONCLUSIONS: Undertaking the primary care of a grandchild is associated with an increase in levels of depression. Particularly in light of the recent dramatic increase in the prevalence of grandparent caregiving in the United States, physicians need to explore familial role changes with midlife and older patients who have symptoms of depression. Special attention should be paid to the most at-risk subsets of grandparent caregivers: those who are new caregivers, those in poor health, those who are younger, and women.  相似文献   
105.
A solar photo-Fenton process combined with a biological nitrification and denitrification system is proposed for the decontamination of a landfill leachate in a pilot plant using photocatalytic (4.16 m2 of Compound Parabolic Collectors - CPCs) and biological systems (immobilized biomass reactor). The optimum iron concentration for the photo-Fenton reaction of the leachate is 60 mg Fe2+ L−1. The organic carbon degradation follows a first-order reaction kinetics (k = 0.020 L kJUV−1, r0 = 12.5 mg kJUV−1) with a H2O2 consumption rate of 3.0 mmol H2O2 kJUV−1. Complete removal of ammonium, nitrates and nitrites of the photo-pre-treated leachate was achieved by biological denitrification and nitrification, after previous neutralization/sedimentation of iron sludge (40 mL of iron sludge per liter of photo-treated leachate after 3 h of sedimentation). The optimum C/N ratio obtained for the denitrification reaction was 2.8 mg CH3OH per mg N-NO3, consuming 7.9 g/8.2 mL of commercial methanol per liter of leachate. The maximum nitrification rate obtained was 68 mg N-NH4+ per day, consuming 33 mmol (1.3 g) of NaOH per liter during nitrification and 27.5 mmol of H2SO4 per liter during denitrification. The optimal phototreatment energy estimated to reach a biodegradable effluent, considering Zahn-Wellens, respirometry and biological oxidation tests, at pilot plant scale, is 29.2 kJUV L−1 (3.3 h of photo-Fenton at a constant solar UV power of 30 W m−2), consuming 90 mM of H2O2 when used in excess, which means almost 57% mineralization of the leachate, 57% reduction of polyphenols concentration and 86% reduction of aromatic content.  相似文献   
106.
Tempeh is a fermented food made of mainly soybeans and is a nutritious, affordable, and sustainable functional source of protein. Globally, tempeh is a widely accepted fermented product. Although there is a growing body of literature on tempeh, most research has focused on unfermented soybeans, thus the impact of tempeh fermentation on biological properties of soybeans has been largely left scattered. The objective of this review is to summarize the literature of tempeh fermentation over the past 60 years. A search of articles on tempeh published from 1960 to 2020 was performed using the Cochrane Library, Web of Science, EBSCOhost FSTA database, and Google Scholar. References from identified articles were reviewed for additional sources. In total, 321 papers were selected for this review, of which 64 papers were related to the health benefits of tempeh. This review concluded that sufficient evidence exists in the literature supporting tempeh fermentation as a low-cost, health-promoting, and sustainable food processing technology to produce protein-rich foods using various beans, legumes, and grains. This comprehensive review suggests further studies are needed on tempeh fermentation and its impact on human health; research and standardization of nonsoy tempeh; assessment of food safety-improving modification in tempeh production system; and initiatives supporting the sourcing of local ingredients in tempeh production.  相似文献   
107.
正在商品浆的供给方面,亚洲新兴国家和拉丁美洲的全球市场份额有望从1995年17%提升到2025年的50%;在商品浆的需求方面,亚洲新兴国家和拉丁美洲的全球市场份额有望从1995年21%提升到2025年的61%。全球纸浆用材及纸浆供给的关键问题,纸浆需求的增长推动了纸浆用材和纸浆供给的商业模式的创新和扩大发展。下面分四个方面介绍:  相似文献   
108.
Metal-polymer hybrid structures can be used as an alternative solution for reducing weight and fuel consumption in the transport industry, which aims to minimise the emission of harmful gases that have a greenhouse effect. Friction riveting is a relatively new technique for joining metal-polymer hybrid structures. The process is based on the generation of frictional heat between the components, resulting in the plastic deformation of the end of the metal rivet, which is anchored inside the polymer component. This study assessed the technical feasibility of joining AA 6056 T6 and PA6, focusing on the influence of the rotational speed of the rivet on the mechanical performance of the joints. The maximum temperature reached during the process increased with the rotational speed, from 291 ± 6 °C with 10,000 rev/min to 375 ± 5 °C with 15,000 rev/min. The use of higher rotational speeds led to the tip of the rivet undergoing plastic deformation during the friction phase. This produced mechanically stronger joints, because the metal rivet was anchored more securely in the polymer block. The AA 6056 T6-PA6 joints perform well in terms of tensile strength, reaching 85% of the tensile strength of the metal rivet. We therefore confirmed that it is possible to join AA 6056 T6 and PA6 using the technique of friction riveting, and that rotational speed directly affects the tensile strength of the joints.  相似文献   
109.
Second degree burns require dressings to heal. The ideal dressing should keep a moist environment, have low cost, be elastic and have a bactericidal effect. The potential of PVA‐NaCMC (sodium carboxymethyl cellulose) gels to combine the mechanical and swelling properties of PVA with the flexibility and high water uptake of NaCMC and the antimicrobial characteristics of propolis is investigated. The freeze‐thawed gels were characterized by FTIR and DSC. Their swelling behavior, their mechanical response, the delivery of active compounds and their antimicrobial properties were also determined. The main findings of the FTIR analysis were that no chemical bonding occurred between the materials. The DSC analysis revealed that the addition of NaCMC to PVA lowered the PVA crystallinity, as did the addition of propolis, leading to a more deformable gel (as can be observed from the tensile tests results). This also resulted in a higher rate of delivery of active compounds, higher weight loss and higher fluid uptake than comparable PVA‐propolis systems, as shown by the swelling tests and by the propolis delivery tests. Samples with 15% propolis content or more inhibited S. aureus colonies with 80% reduction, and are therefore highly absorbent and compliant antimicrobial gels for wound healing. POLYM. ENG. SCI., 57:1224–1233, 2017. © 2017 Society of Plastics Engineers  相似文献   
110.
Yet Another Map Algebra   总被引:2,自引:0,他引:2  
This paper describes features of a language approach for map algebra based on the use of algebraic expressions that satisfy a concise formalism. To be consistent with formal approaches such as geoalgebra and image algebra, the proposed algebraic expressions are suitable not only for the usual modeling of layers but also to describe variable neighborhoods and zones. As a compromise between language and implementation issues we present an implementation strategy based on the theory of automata. The result is an efficient way of implementing map algebra that simplifies its use on environmental and dynamic models without going too far from its well-known paradigm.
Felipe AlmeidaEmail:
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