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61.
Light scattering by kaolinite dust samples at 532 nm is studied using a newly developed laboratory apparatus. During the experiments, dust samples are suspended in water, aerosolized by a nebulizer, and then injected into the scattering zone, with or without going through a diffusion drier, to generate either dried dust particles or water droplets with dust inclusions. The light source is a dual wavelength (532 and 1064 nm) diode-pumped solid state laser. Light scattered by an ensemble of particles is collected by a charge-coupled device (CCD) camera, which is mounted on the rotating arm of a stepper motor. The stepper motor rotates the CCD to cover the scattering angle range from 3° to 177°. Polarized scattering light is measured for the horizontally and vertically polarized incident light. The apparatus is calibrated, using pure water droplets as the scattering media. The response function with respect to the scattering angle is obtained by comparing the measurements with Lorenz–Mie calculations and then used in the later data analysis. Measurements show that the backward scattering features of the water droplets are smoothened due to their dust inclusions. Numerical simulations and measurements are extensively compared and discussed. It is found that the Lorenz–Mie theory is inadequate to reproduce the scattering phase functions of either dust particles or water droplets with dust inclusions. A nonspherical aggregate model is applied to simulate the scattering phase functions. The simulation is able to reproduce the overall scattering features; however, substantial discrepancies still exist due to uncertainties in particle shape and refractive index.

Copyright © 2018 American Association for Aerosol Research  相似文献   

62.
Tracer tests were conducted at the 6,000 pounds of ozone per day Tucson, CAP Water Treatment Plant in Tucson, Arizona. The tests were designed to determine T10 values through the contactors at various operating conditions. The tests were modeled using three techniques. Peclet Number was calculated for each of the runs, which would indicate the hydrodynamic conditions inside the ozone contactor. The results indicated that the increase in water flow rate and the number of cells with gas flow increased Peclet Number. The flow rate of liquid seemed to impact the Peclet Number more than gas flow. The headloss in each cell appeared to be important in controlling the distribution of liquid and gas through the cell. A correlation was developed between the product of gas and liquid phase Reynolds Number and Peclet Number.  相似文献   
63.
A low-cost, nonvacuum, solution precursor route has been developed to produce epitaxial oxide buffer layers of Eu2O3 or La2Zr2O7 on biaxially textured Ni (100) tapes. A reel-to-reel continuous dip-coating unit consisting of a constant-tension tape transport system attached to a controlled atmosphere furnace was fabricated. Nickel tapes were pulled through a 2-methoxyethanol solution of europium methoxyethoxide/acetate or lanthanum zirconium methoxyethoxide. The double-sided dip-coated tapes were then annealed in a preheated furnace at 1000°–1100°C with a high flow rate of Ar/H2 (4%) gas. The dip-coated buffers were dense, continuous, crack-free, and epitaxial with a single cube texture. A critical current ( J c) of >1 MA/cm2 at 77 K and self-field was obtained for YBa2Cu3O7-δ (YBCO) films with a layer sequence of YBCO ( ex situ BaF2 process)/CeO2 (sputtered)/YSZ (sputtered)/Eu2O3 (dip-coated)/nickel. We have produced 1–2 m lengths of epitaxial buffer layers on textured nickel substrates using a nonvacuum process for the first time.  相似文献   
64.
65.
The quality of dried meat products and their drying kinetics significantly depends on the status of the raw material going into the drying process. The aim of this study was to determine the impact of meat status (fresh, mature, frozen–thawed) on the drying kinetics and the resulting quality in terms of color changes and spectrally deductible information. Drying tests were conducted using meat from organically raised bulls. In the fresh meat, freezing leads to a decrease in the drying rate, while for matured meat, the opposite is true. Aging and freezing have little effect on the end product quality in terms of final product color. However, water content can be detected hyperspectrally and resolved spatially for all stages of the process. With regard to water content prediction, the Monte-Carlo uninformative variable elimination-partial least square method performs best for the fresh and fresh frozen–thawed version with seven wavelengths, an r2 of 0.97 and 0.88, and RMSE (Root mean squared error) of 0.15 and 0.17 for the test set, respectively.  相似文献   
66.
1‐Pentene was polymerized with the syndiospecific catalyst system i‐PrC(Cp)(9‐fluorenyl)ZrCl2/MAO. The molar mass of the resulting polymers depends strongly on the reaction temperature and decreases from w = 126 000 at 0°C to w = 46 000 at 100°C, but is more or less independent of the monomer and the MAO concentration. The influence of reaction temperature and concentrations of MAO and monomer on the type of end‐groups generated during the chain termination, as well as on the type of stereoerror, was investigated. The degree of tacticity was dependent on the polymerization temperature with [rrrr] > 0.99 at 0°C and [rrrr] = 0.75 at 100°C.  相似文献   
67.
A network of biological databases is reviewed, supplying a framework for studies of human genes and the association of their genomic variations with human phenotypes. The network is composed of GeneCards, the human gene compendium, which provides comprehensive information on all known and predicted human genes, along with its suite members GeneDecks and GeneLoc. Two databases are shown that address genes and variations focusing on olfactory reception (HORDE) and transduction (GOSdb). In the realm of disease scrutiny, we portray MalaCards, a novel comprehensive database of human diseases and their annotations. Also shown is GeneKid, a tool aimed at generating novel kidney disease biomarkers using systems biology, as well as Xome, a database for whole-exome next-generation DNA sequences for human diseases in the Israeli population. Finally, we show LifeMap Discovery, a database of embryonic development, stem cell research and regenerative medicine, which links to both GeneCards and MalaCards.  相似文献   
68.
The forthcoming introduction of lower standards for arsenic in drinking water requires new technologies for arsenic removal. We report the development of an electrochemical unit for remediating domestic water supplies for homes without municipally treated water. Electrolysis in a two‐anode system provides oxidants to convert As(III) to As(V) in situ, and a sacrificial anode to deliver iron into solution. Conditioning tanks after each electrolysis step ensure completion of the chemical reactions. At the pH of domestic water, As(V) co‐precipitates with Fe(OH)3; subsequent filtration leaves <10 ppb of inorganic arsenic in solution.  相似文献   
69.
The H + D2 reactive system was studied in the energy range 0.84 < Etr < 2.70 eV employing the ordinary Quasi-Classical Trajectory Approach (QCTA), the Classical and the Quantum Reactive Infinite Order Sudden Approximations (CRIOSA and QRIOSA), and the Angle-Oriented Transition State Theory (AOTST). From a detailed analysis of the various integral cross-sections and opacity functions, it was concluded that pronounced quantum effects ( > 10%) are expected in the high-energy region (≤ 2 eV).  相似文献   
70.
丁基橡胶是一种具有多种独特属性的神奇材料。这是我们所有的产品线中为数不多可食用产品。我们是全球口香糖行业唯一的原料供应商。然而,并不是出于这个原因,我的业务部才决定在新加坡兴建新的丁基橡胶生产厂——朗盛历史上金额最大的投资项目。下面,我将向大家解释朗盛为什么要将新工厂设在新加坡,以及我们是如何应对轮胎行业(为公车、卡车和汽车提供轮胎)市场变化。同时,这些变化为朗盛带来了绝佳的发展机会。  相似文献   
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