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排序方式: 共有268条查询结果,搜索用时 46 毫秒
41.
Litigation strategies often depend upon decisions made during or prior to the start of design or development of a product The features of a liability prevention program are reviewed so that documents with the necessary technical content for successful defense of a litigation will be available if needed. Their development during the design, manufacturing, and marketing phases of a product's life can benefit product safety, quality, and cost. 相似文献
42.
水酶法提取葵花籽油的研究 总被引:1,自引:0,他引:1
采用水酶法提取葵花籽油并对其提取条件进行研究,以脱壳葵花籽为原料,采用复合纤维素酶提取葵花籽油,通过单因素实验及正交试验,研究了料液比、浸提温度、浸提时间、加酶量、酶解温度、酶解时间等因素对出油效率的影响,确定最佳提油工艺参数。结果表明最佳提取条件为料液比1∶10,浸提温度90℃,浸提时间9 h,复合纤维素酶添加量0.10 g,酶解温度50℃,酶解时间1 h,出油效率可达到79.07%。 相似文献
43.
本文应用环状裂纹受拉圆棒试样的尺寸效应于测定中低强度钢的平面应变断裂韧度K_(IC)。所用试样的尺寸比标准试样小很多。用J积分分析了尺寸效应,并通过有限元计算和断口分析探讨了允许用较小尺寸的圆棒试样测定K_(IC)的原因。 相似文献
44.
We report measurements of rapid ordering and preferential alignment in block copolymer films zone annealed below the order-disorder transition temperature. The orientational correlation lengths measured after approximately 5 h above the glass-transition temperature ( approximately 2 microm) were an order of magnitude greater than that obtained under equivalent static annealing. The ability to rapidly process polymers with inaccessible order-disorder transition temperatures suggests zone annealing as a route toward more robust nanomanufacturing methods based on block copolymer self-assembly. 相似文献
45.
Sebeková K Boor P Valachovicová M Blazícek P Parrák V Babinská K Heidland A Krajcovicová-Kudlácková M 《Molecular nutrition & food research》2006,50(9):858-868
Conditions predisposing to metabolic syndrome (MetS) are associated with increased oxidative stress and inflammation. We studied, in vegetarians (n = 90) and omnivores (n = 46), the impact of the dietary regimen on the occurrence of MetS risk factors (RFs: BMI, blood pressure, glucose metabolism and lipid profile) in relation to oxidative status (advanced glycation end products (AGEs), advanced oxidation protein products (AOPPs), malondialdehyde, ferric reducing ability of plasma, vitamins A, E, C, beta-carotene and superoxide dismutase activity) and microinflammation (C-reactive protein, leukocytes and neopterin). The proportion of subjects without/positive for one or two MetS RFs was comparable between the groups. From the components of MetS only immunoreactive insulin levels differed significantly (95% CI: omnivores: 5.0-7.1 microU/mL, vegetarians: 4.5-5.4, p = 0.03). Omnivores had lower AOPP (omnivores: 0.29-0.36 micromol/g albumin, vegetarians: 0.36-0.52, p = 0.01) and beta-carotene levels than vegetarians, they consumed more calories, proteins, fat and saturated fatty acids, and less fibres, beta-carotene and vitamin C. Multiple regression analysis revealed vitamin E and AOPP levels as the most important independent determinants of MetS RFs. The vegetarian diet seems to exert beneficial effects on MetS RFs associated microinflammation. Whether the vegetarian diet may counteract the deleterious effects of elevated AOPPs and AGEs, remains to be elucidated. 相似文献
46.
47.
Youngwoo Nam Jai Seung Yoo Yung Woo Park Niclas Lindvall Thilo Bauch August Yurgens 《Carbon》2012,50(15):5562-5568
We measured the Aharonov-Bohm (AB) effect in graphene rings with superconducting-(Al) and normal-metal (Au) mirrors. The mirrors were deposited either on additional stubs connected to the rings in the transverse direction or on the ring bias lines. A significant enhancement of the visible phase coherence was observed in the latter case, in which we observed even the third harmonic of the AB oscillations. The superconductivity of the mirrors appears to be unimportant for the improved coherence in graphene. A large Fermi energy mismatch between graphene and the mirror material is sufficient for this effect. In addition, a transport gap was observed in our graphene structures at the gate voltage close to the Dirac point. The value of the gap can be reproduced by assuming the occurrence of Coulomb blockade effects in graphene. 相似文献
48.
Chopra Mohit P.; Landes Reid D.; Gatchalian Kirstin M.; Jackson Lisa C.; Buchhalter August R.; Stitzer Maxine L.; Marsch Lisa A.; Bickel Warren K. 《Canadian Metallurgical Quarterly》2009,17(4):226
During a 12-week intervention, opioid dependent participants (N = 120) maintained on thrice-a-week (M, W, F) buprenorphine plus therapist and computer-based counseling were randomized to receive: (a) medication contingencies (MC = thrice weekly dosing schedule vs. daily attendance and single-day 50% dose reduction imposed upon submission of an opioid and/or cocaine positive urine sample); (b) voucher contingency (VC = escalating schedule for opioid and/or cocaine negative samples with reset for drug-positive samples); or (c) standard care (SC), with no programmed consequences for urinalysis results. VC resulted in better 12-week retention (85%) compared to MC (58%; p = 0.009), but neither differed from SC (76% retained). After adjusting for baseline differences in employment, and compared to SC, the MC group achieved 1.5 more continuous weeks of combined opioid/cocaine abstinence (p = 0.030), while the VC group had 2 more total weeks of abstinence (p = 0.048). Drug use results suggest that both the interventions were efficacious, with effects primarily in opioid rather than cocaine test results. Findings should be interpreted in light of the greater attrition associated with medication-based contingencies versus the greater monetary costs of voucher-based contingencies. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
49.
50.
RSV is one of the major infectious agents in paediatrics, and its relationship with air pollution is frequently observed. However, the molecular basis of this interaction is sparsely reported. We sought to systematically review the existing body of literature and identify the knowledge gaps to answer the question: which molecular mechanisms are implied in the air pollutants–RSV interaction? Online databases were searched for original studies published before August 2022 focusing on molecular mechanisms of the interaction. The studies were charted and a narrative synthesis was based upon three expected directions of influence: a facilitated viral entry, an altered viral replication, and an inappropriate host reaction. We identified 25 studies published between 1993 and 2020 (without a noticeable increase in the number of studies) that were performed in human (n = 12), animal (n = 10) or mixed (n = 3) models, and analysed mainly cigarette smoke (n = 11), particulate matter (n = 4), nanoparticles (n = 3), and carbon black (n = 2). The data on a damage to the epithelial barrier supports the hypothesis of facilitated viral entry; one study also reported accelerated viral entry upon an RSV conjugation to particulate matter. Air pollution may result in the predominance of necrosis over apoptosis, and, as an effect, an increased viral load was reported. Similarly, air pollution mitigates epithelium function with decreased IFN-γ and Clara cell secretory protein levels and decreased immune response. Immune response might also be diminished due to a decreased viral uptake by alveolar macrophages and a suppressed function of dendritic cells. On the other hand, an exuberant inflammatory response might be triggered by air pollution and provoke airway hyperresponsiveness (AHR), prolonged lung infiltration, and tissue remodeling, including a formation of emphysema. AHR is mediated mostly by increased IFN-γ and RANTES concentrations, while the risk of emphysema was related to the activation of the IL-17 → MCP-1 → MMP-9 → MMP-12 axis. There is a significant lack of evidence on the molecular basics of the RSV–air pollution interaction, which may present a serious problem with regards to future actions against air pollution effects. The major knowledge gaps concern air pollutants (mostly the influence of cigarette smoke was investigated), the mechanisms facilitating an acute infection or a worse disease course (since it might help plan short-term, especially non-pharmacological, interventions), and the mechanisms of an inadequate response to the infection (which may lead to a prolonged course of an acute infection and long-term sequelae). Thus far, the evidence is insufficient regarding the broadness and complexity of the interaction, and future studies should focus on common mechanisms stimulated by various air pollutants and a comparison of influence of the different contaminants at various concentrations. 相似文献