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41.
Three fractions of polysaccharides that have high biological activity were extracted from Chinese bamboo leaves (Indocalamus Tesselatus) with 0.9% sodium chloride, 1% ammonium oxalate and 85% ethanol. Their component sugars were investigated by paper chromatography developed with n-butanol-pyridine-water (6:4:3 by vol), and by gas chromatography with crown ester stationary-phase-fused silica capillary column. Their monosaccharide compositions are different from each other with glucuronic acid, galactose, arabinose, mannose, glucose, and xylose (52, 18, 9, 7 and 6%, respectively) in one fraction, only glucuronic acid in another and glucuronic acid, fucose, arabinose and xylose (36, 31, 24 and 9%, respectively) in the third fraction. The protection effect of two polysaccharides against experimental hepatitis was studied in mice. 相似文献
42.
D Arslan F Oztürk T Patiro?lu M Kü?ükaydin Z Gündüz 《Canadian Metallurgical Quarterly》1996,38(3):361-366
Angiofollicular lymph node hyperplasia or Castleman's Disease (CD) is a rare lymphoproliferative disorder that manifests itself as a local or generalized tumor-like condition affecting both lymph nodes and non-nodal tissues, usually in the chest and abdomen. Hyaline vascular and plasma cell types have been identified histologically. A new clinical form of CD with multisystemic involvement has been defined as multicentric Castleman's disease. It is very rare in childhood. In this paper we present an eight-year-old boy with multicentric Castleman's disease. 相似文献
43.
Mohammed Saleh Zeynep Bilici Merve Kaya Mutlu Yalvac Hudaverdi Arslan H. Cengiz Yatmaz Nadir Dizge 《Advanced Powder Technology》2021,32(4):1264-1275
The use of naturally present heterogeneous catalysts has recently been an essential issue in the Fenton and photo-Fenton processes. In this study, the uses of basalt as a catalyst for the Fenton and photo-Fenton reactions for methylene Blue (MB) and Basic Red 18 (BR18) degradations were investigated. Basalt was selected because of the presence of the iron (III) oxide in the structure. Basalt was characterized by X-Ray Fluorescence (XRF) and X-Ray Diffraction (XRD) analysis to obtain the chemical composition and the crystalline phase. The surface charge and the surface area were obtained by zeta potential and Brunauer Emmett-Teller (BET) analysis. Fourier Transform Infrared Spectroscopy (FTIR) and scanning electron microscope (SEM) were utilized to explore the functional group and the surface morphology. Fenton and photo-Fenton processes were applied to explore the best degradation method. Adsorption was also tested and the adsorption process had minimum removal efficiency (12% for MB and 17% for BR18). The removal efficiencies for MB and BR18 by the Fenton process were 87% and 28%, respectively. The photo-Fenton process had maximum removal efficiency with 100% for MB and 70% for BR18. The optimum conditions were 70 mg/L dye concentration, 5 mM H2O2, 1.0 g/L basalt loading and pH 2. Basalt has shown reuse capability as a catalyst for three consecutive cycles. 相似文献
44.
45.
Enes Yigit Sevket Demirci Atilla Unal Caner Ozdemir Alexey Vertiy 《Journal of Infrared, Millimeter and Terahertz Waves》2012,33(12):1227-1238
In this paper, millimeter-wave imaging of foreign object debris (FOD)-type objects on the ground is studied with the help of ground-based synthetic aperture radar (GB-SAR) technique. To test the feasibility of detecting runway FODs with this technique, some preliminary experiments are conducted within short antenna-to-target ranges of small imaging patches. An automated stripmap GB-SAR system with stepped-frequency transmission is constructed together with a quasi-monostatic data collection operation. The imaging experiments for various braces and screws are then carried out by using 32–36?GHz and 90–95?GHz frequency bands of the millimeter-wave. Images reconstructed by a matched-filter based algorithm are analyzed to determine the proper system parameters for an efficient imaging and to comprehend the factors against a successful detection. Results demonstrate the capability of GB-SAR imaging in accurately locating these FOD-like targets under near-range operating conditions. 相似文献
46.
Yasemin Arslan Udum Hüseyin Bekir Yıldız Hacer Azak Elif Sahin Oktay Talaz Ali Çırpan Levent Toppare 《应用聚合物科学杂志》2014,131(17)
New π‐conjugated polymers containing dithieno(3,2‐b:2′,3′‐d)pyrrole (DTP) were successfully synthesized via electropolymerization. The effect of structural differences on the electrochemical and optoelectronic properties of the 4‐[4H‐dithieno(3,2‐b:2′,3′‐d)pyrrol‐4‐yl]aniline (DTP–aryl–NH2), 10‐[4H‐dithiyeno(3,2‐b:2′,3′‐d)pirol‐4‐il]dekan‐1‐amine (DTP–alkyl–NH2), and 1,10‐bis[4H‐dithieno(3,2‐b:2′,3′‐d)pyrrol‐4‐yl] decane (DTP–alkyl–DTP) were investigated. The corresponding polymers were characterized by cyclic voltammetry, NMR (1H‐NMR and 13C‐NMR), and ultraviolet–visible spectroscopy. Changes in the electronic nature of the functional groups led to variations in the electrochemical properties of the π‐conjugated systems. The electroactive polymer films revealed redox couples and exhibited electrochromic behavior. The replacement of the DTP–alkyl–DTP unit with DTP–aryl–NH2 and DTP–alkyl–NH2 resulted in a lower oxidation potential. Both the poly(10‐(4H‐Dithiyeno[3,2‐b:2′,3′‐d]pirol‐4‐il)dekan‐1‐amin) (poly(DTP–alkyl–NH2)) and poly(1,10‐bis(4H‐dithieno[3,2‐b:2′,3′‐d]pyrrol‐4‐yl) decane) (poly(DTP–alkyl–DTP)) films showed multicolor electrochromism and also fast switching times (<1 s) in the visible and near infrared regions. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014 , 131, 40701. 相似文献
47.
牛奶蛋白纤维(第Ⅰ部分) 总被引:1,自引:0,他引:1
牛奶蛋白纤维是一种新颖的工业生产纤维,中国已拥有2项发明专利.2004年它就已经通过了国际生态纺织品Oeko-Tex标准100认证.牛奶蛋白纤维是利用新型生物工程技术将牛奶去水脱脂,加工成适用于湿法纺丝工艺的蛋白浆后制得的纤维.它对皮肤友好,手感舒适,色彩鲜艳,具有很好的可染性.牛奶蛋白纤维可以纯纺或与羊绒、蚕丝、棉、毛、麻及其他纤维混纺. 相似文献
48.
Fawaz N. S. Al-Heibshy Ebru Başaran Rana Arslan Naile Öztürk İmran Vural 《Drug development and industrial pharmacy》2013,39(10):1635-1645
AbstractObjective: The aim of the study was to formulate, cyclodextrin (CD)-polyanhydride (PA) nanoparticles (CPNs) with rosuvastatin calcium (RCa) in order to enhance the poor oral bioavailability.Methods: CPNs containing RCa/CD complexes were prepared by a modified solvent displacement method and morphological analyses, particle size (PS), polydispersity index (PDI), zeta potential (ZP), encapsulation efficiency (EE), DSC, FT-IR, XRD, 1H-NMR analyses were performed. In vitro release properties, release kinetics, cytotoxicity, in vitro permeability and pharmacokinetic studies were also studied. The stability of the formulations were evaluated during the storage period of 3?months.Results: The physicochemical studies showed that the RCa/CD complexes were well incorporated into CPNs resulted in nanosized particles (215.22 and 189.13?nm) with homogenous size distribution (PDI: 0.203 and 0.182) with relatively high incorporation capacity (76.11 and 68.18%) for the CPN1 and CPN2 formulations respectively. Sustained release of RCa from CPNs were achieved. The cytotoxicity values showed that the safety of the formulations. According to permeability studies, pure RCa had lowest permeability data (3.08?×?10?7?cm?s?1 Papp value) while CPNs gained higher permeability data (1.36?×?10?5 and 1.12?×?10?5?cm?s?1 Papp values) for the CPN1 and CPN2 formulations respectively. CPN2 formulation was selected for pharmacokinetic studies and analyses results demonstrated that approximately 8-fold relative oral bioavailability enhancement compared to the pure RCa was achieved.Conclusion: Considering the analyses results of the study, CPNs can be regarded as suitable, safe, functional oral delivery systems for RCa with enhanced oral bioavailability. 相似文献
49.
The amount of retained austenite in the quenched cold work tool steel sample is 17.7%, in the condition of sub-zero heat treated and double tempered samples following by quenching is 1.9% determined by XRD analysis. The types of carbides (MC, M7C3, M23C6) present in the structure was determined by XRD and SEM-EDS analysis. The hardness of test samples were 865 HV(0.1) for quenched sample and 785 HV(0.1) forth sample subjected to sub-zero treatment and double tempered after the quenching. 相似文献
50.