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201.
    
The Lewis acid–base adduct approach has been widely used to form high-crystalline perovskite films, but the complicated crystallization pathway and underlying film formation mechanism are still ambiguous. Here, the detailed crystallization process of perovskites manipulated by Lewis base additives has been revealed by in situ X-ray scattering measurements. Through monitoring the film formation process, two distinct crystal growth stages have been definitely recognized: i) an intermediate phase-dominated stage; and ii) a phase transformation stage from intermediates to crystalline perovskite phase. Incorporating Lewis base additives significantly prolongs the duration of stage 1 and induces a postponed phase transformation pathway, which could be responsible for retardant crystallization kinetics. Based on a series of experimental results and theoretical calculations, it is indicated that the manipulation of perovskite crystallization pathway is a result of the modulated molecular interactions between Lewis base additives and solution precursors. Owing to the retardant crystallization kinetics, enhanced-quality perovskite films with reduced defect density and improved optoelectronic properties, as well as optimized photovoltaic performance have been demonstrated. This work provides in-depth understanding with respect to perovskite crystallization pathway modulated by Lewis base additives and perceptive guidelines for precise regulation of crystallization kinetics of perovskite film toward high performance.  相似文献   
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Today's mechanical fluid separators in industry are mostly operated without any control to maintain efficient separation for varying inlet conditions. Controlling inline fluid separators, on the other hand, is challenging since the process is very fast and measurements in the multiphase stream are difficult as conventional sensors typically fail here. With recent improvement of process tomography sensors and increased processing power of smart computers, such sensors can now be potentially used in inline fluid separation. Concepts for tomography-controlled inline fluid separation were developed, comprising electrical tomography and wire-mesh sensors, fast and massive data processing and appropriate process control strategy. Solutions and ideas presented in this paper base on process models derived from theoretical investigation, numerical simulations and analysis of experimental data.  相似文献   
203.
In this attempt, novel conjugated polymer/graphite nanocomposites with exposed surface area were fabricated by in situ polymerization using polyaniline, poly(methyl methacrylate) and poly(propylene glycol)-block-poly(ethylene glycol) block- poly(propylene glycol) as matrices and functionalized graphite as a filler. Structural and morphological analysis revealed the modification of graphite as well as oxidative polymerization of numerous matrices over the surface of modified graphite ensuing multilayered nanocomposites. The increased values of Tg (59 and 103°C) obtained from thermal analysis reflect the improved thermal stability of prepared nanocomposites and exhibit better adsorption capacity (35.5cm3/g). Maximum electrical conductivity (7.4 S/cm) was also observed for multilayered nanocomposite.  相似文献   
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In the present work we prepared Aluminum doped Zinc Oxide (AZO) thin films from powder targets. Various concentrations (W/W percentages) of Al2O3 such as1%, 2%, 3%, 4%, 5%, 6%, 7% and 8% were mixed in ZnO powder and made in the form of a 3 inch disc target. These ceramic targets are sputtered in RF magnetron sputtering unit for the deposition of AZO thin films. Optical and electrical properties are analyzed to get an optimized percentage of mixing for achieving high transparency and low resistivity. At Al2O3 percentage of 3% there is a considerable decrement in the resistivity, and at 7% there is a considerable decrease in the optical transmittance. Mobility and carrier concentration are increasing with Al2O3 percentage. Bandgap of the films is observed to be decreasing with increasing the Al2O3 percentage.  相似文献   
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Summary HTST-pasteurized orange drink packed in clear, green and amber glass bottles and coextruded wax laminated paper (TetraPak), was exposed to fluorescent light of 50–60 ft-C for 32 days at ambient room temperature. Chemical analysis revealed significant effect of packages and light on different quality parameters during storage (P<0.05). Ascorbic acid losses amounted 60.6%, 54.6%, 51.0%, and 45.5% in clear glass, green glass, TetraPak, and amber glass respectively against 42.4% in the unexposed control during 32 days storage. Titratable acidity, Brix, Brix-acid ratio, light transmission and cloud-settling generally showed an increasing pattern with advanced storage. Brown glass gave the best protection followed by TetraPak, green glass and clear glass. Evaluation of the drink for sensory components indicated a congruent pattern of changes in the ratings which correlated with the packaging materials tested.
Einfluß der Verpackung und von fluoreszierendem Licht auf ultrahocherhitzten Orangensaft
Zusammenfassung Ultrahocherhitztes Orangengetränk in durchsichtigen, grünen bzw. gelbbraunen Glasflaschen und TetraPak-Verpackung wurde bei Raumtemperatur 32 Tage lang fluoreszierendem Licht (50–60 ft-C) ausgesetzt. Die chemische Analyse ergab einen signifikanten Einfluß der Verpackung and des Lichtes auf verschiedene Qualitätsparameter während der Lagerung (P<0,05). Die Ascorbinsäure-Verluste betrugen im durchsichtigen Glas 60,6%, im grünen Glas 54,6%, in TetraPak 51,0% und im gelbbraunen Glas 45,5% bezogen auf die Kontrollprobe mit 42,4% nach 32 Tagen. Der titrierbare Säuregrad, die Brix-Werte bzw. deren Verhältnis, die Lichtdurchlässigkeit und der Trub zeigten zunehmende Werte nit fortschreitender Lagerung. Danach gibt das braune Glas den besten Schutz, gefolgt von TetraPak, grünen Glas and schließlich durchsichtigen Glas. Die sensorische Wertung ging konform nit den Einfluß des Verpackungsmaterials.
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210.
Different biological materials such as edible oils, refined and unrefined cane and beet sugar and tea (black and green) leaves were assayed for the heavy metals cadmium, copper, lead and zinc. The results revealed significant differences in heavy metal contents within each class of the biological materials (P < 0.05). Cadmium was not detectable in sugar samples. Among the oils, highest amounts of copper (0.263 μg/g) and lead (0.154 μg/g) were in corn oil and zinc in olive oil (3.01 μg/g) whereas cadmium exhibited a narrow range (0.023–0.033 μg/g). The samples of beet-sugar generally contained higher levels of the heavy metals than cane-sugar. Black and green tea leaves contained 0.411–0.908 μg Cd/g, 6.500–9.220 μg Cu/g, 2.200–5.238 μg Pb/g, and 14.500–25.180 μg Zn/g.  相似文献   
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