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991.
Tristan Kolb Christian Neuber Marie Krysak Christopher K. Ober Hans‐Werner Schmidt 《Advanced functional materials》2012,22(18):3865-3873
Each film preparation technique affects the physical properties of the resulting coating and thus defines its applicability in modern device construction. In this context solvent based spin coated and solvent‐free physical vapor deposited molecular glass photoresist films are systematically investigated for their dissolution behavior, sensitivity, and overall lithographic performance. These investigations demonstrate that the solvent‐free physical vapor deposition leads to a marked increase in sensitivity. This could be explained by the individual molecule by molecule deposition step producing a more homogeneous distribution of the multicomponent resist system, especially the photoacid generator. In addition, this assumption is supported by former published simulations focusing on aggregate formation within thin films. This work demonstrates that the lithographic sensitivity of multicomponent resist system is an intrinsic parameter to investigate molecular material distribution and indicates that the applied film preparation technique is crucial for the corresponding performance and applicability. 相似文献
992.
993.
The thickness of CoP thin films prepared by wet chemical deposition is of crucial importance on magnetic property and recording perform-ance. The coercivity of CoP films decreased with increasing film thickness. The coercivity was 45.37 kA m 1 at the thickness of 300 nm, and decreased to 21.65 kA m 1 at 5.7 μm. Recording performance tests indicate that, for drums with the same size, different recorded magnetic pole density have different thickness requirements. For 40 mm diameter magnetic drum, the optimal ... 相似文献
994.
995.
In the present paper, a series of nanostructured cobalt ferrite systems was synthesized in different compositions via chemical co-precipitation method. The X-ray diffraction analysis of cobalt ferrite systems confirmed the formation of its nanoparticles having minimum crystallite size 7 nm. The surface morphologies of the cobalt ferrite illustrate the distribution of partially agglomerated spherical nanoparticles having particle size ~12 nm. The magnetic behaviors of the synthesized materials were characterized by magnetic measurements. Liquefied petroleum gas sensing investigations of the fabricated pellets illustrate that the cobalt ferrite synthesized in 1:1 M ratio possesses an improved response in comparison to other compositions. The maximum sensitivity of cobalt ferrite film sensor was 2.0 MΩ/s. The response and recovery times were ~30 and 60 s, respectively. The sensor was 95% reproducible after three months of fabrication of the film, showing the stability of the fabricated sensor. 相似文献
996.
Hua Xiong Shen‐qi Wang Chun‐qing Bai Qiang Zhao 《International Journal of Food Science & Technology》2014,49(1):91-97
Zero‐trans interesterified fats were produced from camellia seed oil (CSO), palm stearin (PS) and coconut oil (CO) with three weight ratios (CSO/PS/CO, 50:50:10, 40:60:10 and 30:70:10) using Lipozyme TL IM. Results showed that the interesterified products contained palmitic acid (34.28–42.96%), stearic acid (3.96–4.72%), oleic acid (38.73–47.95%), linoleic acid (5.92–6.36%) and total medium‐chain fatty acids (MCFA)s (∑MCFAs, 5.03–5.50%). Compared with physical blends, triacylglycerols of OOO and PPP were decreased and formed new peaks of equivalent carbon number (ECN) 44 in the interesterified products. The product CPC3′ showed a slip melting point of 36.8 °C and a wide plastic range of solid fat content (SFC) (45.8–0.4%) at 20–40 °C. Also, the major β′ form was determined. These data indicated that the zero‐trans interesterified fats would have a potential functionality for margarine fats. Subsequently, the antioxidative stabilities of interesterified products with the addition of α‐tocopherol (α‐TOH) and ascorbyl palmitate (AP) were investigated. The results indicated that AP had a dose‐dependent effect at concentrations of 100, 200 and 400 ppm. 相似文献
997.
Subrata Mallick Satyanarayan Pattnaik Kalpana Swain Pintu K. De Arindam Saha Pushpen Mazumdar 《Drug development and industrial pharmacy》2013,39(7):726-734
This present study is a preliminary exploration of the affinity between a carboxylic model drug ibuprofen and aluminum hydroxide. Ibuprofen was comilled with aluminum hydroxide in different weight ratios in the solid state and was characterized by scanning electron microscopy (SEM), X-ray powder diffractometry (XRD), Fourier transform infrared spectroscopy (FTIR), and in vitro dissolution studies. XRD and SEM studies indicated complete interaction of ibuprofen with aluminum hydroxide and complete amorphization of aluminum hydroxide–ibuprofen complexed salt as well, on comilling with aluminum hydroxide at 1:2 ratio. FTIR data showed the disappearance of acid carbonyl peak with the appearance and the corresponding increase in absorbance of new signal at 1,682 cm?1 in the 1:1 and 1:2 ibuprofen–aluminum hydroxide-comilled powder. The accompanied increase in the absorbance of carboxylate peak in the ibuprofen–aluminum hydroxide physical mixture, and 1:0.1, 1:0.5, 1:1, and 1:2 (IBApm, and IB1A0.1, IB1A0.5, IB1A1, and IB1A2, respectively) comilled powder indicated an acid–base reaction between ibuprofen and aluminum hydroxide. On storage at 40°C and 75% relative humidity (RH) for 10 weeks, XRD study showed the absence of reversion to the crystalline state and FTIR data revealed continued increase of new signal at 1,682 cm?1 relative to carboxylic acid peak and no reappearance of carboxylic acid peak. In vitro dissolution studies revealed that the percent release of ibuprofen from the aluminum hydroxide-comilled powder is in the following order: IB1A2 < IB1A1 < ibuprofen crystal < ibuprofen milled alone < IB1A0.1 < IB1A0.5. Aluminum metal cation might have interacted to form a complex through the carboxyl and carbonyl groups of ibuprofen. Improved dissolution of drug associated with IB1A0.1 and IB1A0.5 is because of the absence of a new signal at 1,682 cm?1 and improved amorphization of the drug to some extent. Dissolution of drug affected in IB1A2 and IB1A1 may be because of the insoluble stable complex formation. 相似文献
998.
Yunyan Liu Shanying Yang Gongxiang Wei Jiaoqing Pan Yuzhen Yuan Chuanfu Cheng 《材料科学技术学报》2013,29(12):1134-1138
Znl_xCoxO (x = 0.05) thin films are deposited on sapphire (0001) substrates by laser-molecular beam epitaxy technique at different substrate temperatures. The structural, stress and morphology evolution features are investigated by means of X-ray diffraction and atomic force microscopy. The surface parameters of roughness exponent α, root mean square (RMS) roughness w and autocorrelation length ~ are calculated and the surface parameters are preliminarily analyzed. The values of ~ vary from 0.7 to 0.9. The RMS roughness w is less than 2.2 nm, and it increases with increasing Ts from 300 to 400 °C, and then decreases when Ts is 500 °C. The autocorrelation length ~ decreases monotonously with the increase in Ts from 300 to 500 °C, which indicates that the increase in Ts restrains the spread of the surface fluctuations until Ts is higher than 400 °C. 相似文献
999.
Cobalt oxide thin films were fabricated by means of electrospray deposition. The obtained films were characterized by Raman spectroscopy, X-ray diffraction and Scanning electron microscopy. The solution that was used gave the Co3O4 phase at different growth temperatures. The best granular surfaces were obtained at 250 °C as verified by all characterization techniques, while flaky surfaces were obtained at higher temperatures. The surface morphology is mostly granular except for high temperatures where the cobalt oxide is formed as flakes instead of grains. 相似文献
1000.
In this study, an interval-valued fuzzy robust programming (I-VFRP) model has been developed and applied to municipal solid-waste management under uncertainty. The I-VFRP model can explicitly address system uncertainties with multiple presentations, and can directly communicate the waste manager's confidence gradients into the optimization process, facilitating the reflection of weak or strong confidence when subjectively estimating parameter values. Parameters in the I-VFRP model can be represented as either intervals or interval-valued fuzzy sets. Thus, variations of the waste manager's confidence gradients over defining parameters can be effectively handled through interval-valued membership functions, leading to enhanced robustness of the optimization efforts. The results of a theoretical case study indicate that useful solutions for planning municipal solid-waste-management practices can be generated. The waste manager's confidence gradients over various subjective judgments can be directly incorporated into the modeling formulation and solution process. The results also suggest that the proposed methodology can be applied to practical problems that are associated with complex and uncertain information. 相似文献