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81.
Molybdenum’s role in the electronics market has been an important one since the earliest days of vacuum tubes. Common electronic applications include components used to manufacture electrical devices, including setter tiles for sintering ceramic substrates and multilayer ceramic circuits, as well as physical-vapor deposition masks. Molybdenum is also used for thermal-management applications when paired with copper and is a necessary part of high-power diodes and rectifiers as well as field-emitter components in flat-panel displays. John A. Shields, Jr., is the director of technology at CSM Industries. Pete Lipetzky is chief engineer at PMTI.  相似文献   
82.
Plasma-assisted electron-beam evaporation leads to changes in the crystallinity, density, and stresses of thin films. A dual-source plasma system provides stress control of large-aperture, high-fluence coatings used in vacuum for substrates 1m in aperture.  相似文献   
83.
现在的便携式消费电子产品开始采用容量较大的电池,以满足更大屏幕以及更多无线功能(如WiFi、3G、和LTE)所带来的额外的功率需求。目前采用USB接口进行充电已非常普遍,而要进一步提升USB接口的充电效率,以实现更快速的充电,必须有一个能增加PC或集线  相似文献   
84.
In this article, we report a hyperspectral optical imaging application for measurement of the reflectance spectra of photonic structures that produce structural colors with high spatial resolution. The measurement of the spectral reflectance function is exemplified in the butterfly wings of two different species of Lepidoptera: the blue iridescence reflected by the nymphalid Morpho didius and the green iridescence of the papilionid Papilio palinurus. Color coordinates from reflectance spectra were calculated taking into account human spectral sensitivity. For each butterfly wing, the observed color is described by a characteristic color map in the chromaticity diagram and spreads over a limited volume in the color space. The results suggest that variability in the reflectance spectra is correlated with different random arrangements in the spatial distribution of the scales that cover the wing membranes. Hyperspectral optical imaging opens new ways for the non-invasive study and classification of different forms of irregularity in structural colors.  相似文献   
85.
Soil organic carbon (SOC) models such as the Rothamsted Carbon Model (RothC) have been used to estimate SOC dynamics in soils over different time scales but, until recently, their ability to accurately predict SOC stocks/carbon dioxide (CO(2)) emissions from salt-affected soils has not been assessed. Given the large extent of salt-affected soils (19% of the 20.8 billion ha of arable land on Earth), this may lead to miss-estimation of CO(2) release. Using soils from two salt-affected regions (one in Punjab, India and one in South Australia), an incubation study was carried out measuring CO(2) release over 120 days. The soils varied both in salinity (measured as electrical conductivity (EC) and calculated as osmotic potential using EC and water content) and sodicity (measured as sodium adsorption ratio, SAR). For soils from both regions, the osmotic potential had a significant positive relationship with CO(2)-C release, but no significant relationship was found between SAR and CO(2)-C release. The monthly cumulative CO(2)-C was simulated using RothC. RothC was modified to take into account reductions in plant inputs due to salinity. A subset of non-salt-affected soils was used to derive an equation for a "lab-effect" modifier to account for changes in decomposition under lab conditions and this modifier was significantly related with pH. Using a subset of salt-affected soils, a decomposition rate modifier (as a function of osmotic potential) was developed to match measured and modelled CO(2)-C release after correcting for the lab effect. Using this decomposition rate modifier, we found an agreement (R(2) = 0.92) between modelled and independently measured data for a set of soils from the incubation experiment. RothC, modified by including reduced plant inputs due to salinity and the salinity decomposition rate modifier, was used to predict SOC stocks of soils in a field in South Australia. The predictions clearly showed that SOC stocks are reduced in saline soils. Therefore both the decomposition rate modifier and plant input modifier should be taken into account when accounting for SOC turnover in saline soils. Since modeling has previously not accounted for the impact of salinity, our results suggest that previous predictions may have overestimated SOC stocks.  相似文献   
86.
In trying to understand the main trends in the tyre industry, we try to follow a clear sequence through the key ways in which supply and demand ultimately interact.By looking at economic factors and how they interact with the vehicle industry,it is pos- sible to see the implications for the tyre industry.The rising im- portance of trade in the supply/demand balance is also impor- tant.Ultimately,clear trends in production have also emerged as the centre of gravity of the industry has shifted.  相似文献   
87.
Relevance-based abstraction identification: technique and evaluation   总被引:1,自引:1,他引:0  
When first approaching an unfamiliar domain or requirements document, it is often useful to get a quick grasp of what the essential concepts and entities in the domain are. This process is called abstraction identification, where the word abstraction refers to an entity or concept that has a particular significance in the domain. Abstraction identification has been proposed and evaluated as a useful technique in requirements engineering (RE). In this paper, we propose a new technique for automated abstraction identification called relevance-based abstraction identification (RAI), and evaluate its performance—in multiple configurations and through two refinements—compared to other tools and techniques proposed in the literature, where we find that RAI significantly outperforms previous techniques. We present an experiment measuring the effectiveness of RAI compared to human judgement, and discuss how RAI could be used to good effect in requirements engineering.  相似文献   
88.
Previous studies have shown that glaucomatous Schlemm’s canal endothelial cells (gSCECs) are stiffer and associated with reduced porosity and increased extracellular matrix (ECM) material compared to SCECs from healthy individuals. We hypothesised that Schlemm’s canal (SC) cell stiffening was a function of fibrotic changes occurring at the inner wall of SC in glaucoma. This study was performed in primary cell cultures isolated from the SC lumen of human donor eyes. RNA and protein quantification of both fibrotic and endothelial cell markers was carried out on both healthy and gSCECs. Functional assays to assess cell density, size, migration, proliferation, and mitochondrial function of these cells were also carried out. Indeed, we found that gSCECs deviate from typical endothelial cell characteristics and exhibit a more fibrotic phenotype. For example, gSCECs expressed significantly higher protein levels of the fibrotic markers α-SMA, collagen I-α1, and fibronectin, as well as significantly increased protein expression of TGFβ-2, the main driver of fibrosis, compared to healthy SCECs. Interestingly, we observed a significant increase in protein expression of endothelial marker VE-cadherin in gSCECs, compared to healthy SCECs. gSCECs also appeared to be significantly larger, and surprisingly proliferate and migrate at a significantly higher rate, as well as showing significantly reduced mitochondrial activity, compared to healthy SCECs.  相似文献   
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