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121.
计算流体力学模拟可检测拉幅干燥机内的气体流动过程,并对喷嘴指板后端和通风机上端潜在的问题区域进行检测。蒸发过程的模拟表明,织物表面温度与水分的分布不均匀。然而,由于缺乏设备对实验模拟数据进行认征,故无法判断其可靠性。 相似文献
122.
用于聚酯POY生产的WINGS 总被引:1,自引:0,他引:1
Oerlikon Barmag在2007年ITMA国际纺织博览会上以提出的用于化纤装置的全新理念,首次做了名符其实的成功展示。在ITMA2007上展示的新型POY纺丝机的WINGS(卷绕集成导辊的方案),在2008年卖出了1600多次。采用WINGS的几种装置在印度和中国同时成功投产。WINGS已占有全球市场份额的50%以上。 相似文献
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Abstract We show how many-body ground state entanglement information may be extracted from sub-system energy measurements at zero temperature. A precise relation between entanglement and energy fluctuations is demonstrated in the weak coupling limit. Examples are given with the two-state system and the harmonic oscillator, and energy probability distributions are calculated. Comparisons made with recent qubit experiments show this type of measurement provides another method to quantify entanglement with the environment. 相似文献
125.
Andrea Linkmeyer Katharina Hofer Michael Rychlik Markus Herz Hans Hausladen Ralph Hückelhoven 《Food additives & contaminants. Part A, Chemistry, analysis, control, exposure & risk assessment》2016,33(3):489-499
Fusarium head blight (FHB) of small cereals is a disease of global importance with regard to economic losses and mycotoxin contamination harmful to human and animal health. In Germany, FHB is predominantly associated with wheat and F. graminearum is recognised as the major causal agent of the disease, but little is known about FHB of barley. Monitoring of the natural occurrence of FHB on Bavarian barley revealed differences for individual Fusarium spp. in incidence and severity of grain infection between years and between spring and winter barley. Parallel measurement of fungal DNA content in grain and mycotoxin content suggested the importance of F. graminearum in winter barley and of F. langsethiae in spring barley for FHB. The infection success of these two species was associated with certain weather conditions and barley flowering time. Inoculation experiments in the field revealed different effects of five Fusarium spp. on symptom formation, grain yield and mycotoxin production. A significant association between fungal infection of grain and mycotoxin content was observed following natural or artificial infection with the type B trichothecene producer F. culmorum, but not with the type A trichothecene-producing species F. langsethiae and F. sporotrichioides. Trichothecene type A toxin contamination also occurred in the absence of significant damage to grain and did not necessarily promote fungal colonisation. 相似文献
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Markus Wohlschlögel Rainer Steegmüller Andreas Schüßler 《Journal of Materials Engineering and Performance》2014,23(7):2635-2640
Nonmetallic inclusions in Nitinol, such as carbides (TiC) and intermetallic oxides (Ti4Ni2O x ), are known to be triggers for fatigue failure of Nitinol medical devices. These mechanically brittle inclusions are introduced during the melting process. As a result of hot and cold working in the production of Nitinol tubing inclusions are fractionalized due to the mechanical deformation imposed. While the role of inclusions regarding Nitinol fatigue performance has been studied extensively in the past, their effect on Nitinol corrosion behavior was investigated in only a limited number of studies. The focus of the present work was to understand the effect of inclusion size and distribution on the corrosion behavior of medical-device grade Nitinol tubing made from three different ingot sources during different manufacturing stages: (i) for the initial stage (hollow: round bar with centric hole), (ii) after hot drawing, and (iii) after the final drawing step (final tubing dimensions: outer diameter 0.3 mm, wall thickness 0.1 mm). For one ingot source, two different material qualities were investigated. Potentiodynamic polarization tests were performed for electropolished samples of the above-mentioned stages. Results indicate that inclusion size rather than inclusion quantity affects the susceptibility of electropolished Nitinol to pitting corrosion. 相似文献
128.
Angel Medina Markus Schmidt-Heydt Diana L. Cárdenas-Chávez Roberto Parra Rolf Geisen Naresh Magan 《Journal of the Royal Society Interface》2013,10(85)
The objective of this study was to integrate data on the effect of water activity (aw; 0.995–0.93) and temperature (20–35°C) on activation of the biosynthetic FUM genes, growth and the mycotoxins fumonisin (FB1, FB2) by Fusarium verticillioides in vitro. The relative expression of nine biosynthetic cluster genes (FUM1, FUM7, FUM10, FUM11, FUM12, FUM13, FUM14, FUM16 and FUM19) in relation to the environmental factors was determined using a microarray analysis. The expression was related to growth and phenotypic FB1 and FB2 production. These data were used to develop a mixed-growth-associated product formation model and link this to a linear combination of the expression data for the nine genes. The model was then validated by examining datasets outside the model fitting conditions used (35°C). The relationship between the key gene (FUM1) and other genes in the cluster (FUM11, FUM13, FUM9, FUM14) were examined in relation to aw, temperature, FB1 and FB2 production by developing ternary diagrams of relative expression. This model is important in developing an integrated systems approach to develop prevention strategies to control fumonisin biosynthesis in staple food commodities and could also be used to predict the potential impact that climate change factors may have on toxin production. 相似文献
129.
Influence of Surface Modifications on the Spatiotemporal Microdistribution of Quantum Dots In Vivo
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Katharina Nekolla Kerstin Kick Sabine Sellner Karina Mildner Stefan Zahler Dagmar Zeuschner Fritz Krombach Markus Rehberg 《Small (Weinheim an der Bergstrasse, Germany)》2016,12(19):2641-2651
For biomedical applications of nanoconstructs, it is a general prerequisite to efficiently reach the desired target site. In this regard, it is crucial to determine the spatiotemporal distribution of nanomaterials at the microscopic tissue level. Therefore, the effect of different surface modifications on the distribution of microinjected quantum dots (QDs) in mouse skeletal muscle tissue has been investigated. In vivo real‐time fluorescence microscopy and particle tracking reveal that carboxyl QDs preferentially attach to components of the extracellular matrix (ECM), whereas QDs coated with polyethylene glycol (PEG) show little interaction with tissue constituents. Transmission electron microscopy elucidates that carboxyl QDs adhere to collagen fibers as well as basement membranes, a type of ECM located on the basolateral side of blood vessel walls. Moreover, carboxyl QDs have been found in endothelial junctions as well as in caveolae of endothelial cells, enabling them to translocate into the vessel lumen. The in vivo QD distribution is confirmed by in vitro experiments. The data suggest that ECM components act as a selective barrier depending on QD surface modification. For future biomedical applications, such as targeting of blood vessel walls, the findings of this study offer design criteria for nanoconstructs that meet the requirements of the respective application. 相似文献
130.
Rainer Steegmüller Jochen Ulmer Michael Quellmalz Markus Wohlschlögel Andreas Schüßler 《Journal of Materials Engineering and Performance》2014,23(7):2450-2456
New ingot qualities, processed by optimized vacuum arc remelting (VAR), optimized vacuum induction melting followed by VAR and VAR followed by electron beam remelting, were compared with standard quality. Finished components as well as diamond-shaped samples representing a typical dimension of self-expanding stents were produced using Nitinol tubing drawn from the new ingot qualities. Metallographic longitudinal sections were prepared and analyzed to determine inclusion size and distributions of the various ingot qualities. Radial force and uniaxial tensile tests were used to determine the mechanical properties of fully processed material and tubing, respectively. Transformation temperatures of tubing as delivered from supplier and processed stents were measured by differential scanning calorimetry and deformation-and-free-recovery testing. Finally, fatigue tests were performed on diamond-shaped samples to evaluate the strain-life characteristics of the new ingot qualities. Results of this study are compared to ADMEDES historical data from standard Nitinol materials to gain an assessment of the new improved ingot qualities with regard to the production of Nitinol vascular implants. The latest developments in Nitinol ingot quality are highlighted and the results of the comparison from technical point of view are shown. 相似文献