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941.
Lipid carriers for delivery of celecoxib: In vitro,in vivo assessment of nanomedicine in rheumatoid arthritis 下载免费PDF全文
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Naveen Kumar Chenna Pablo Piovano Christian Järnefelt Tapani Vuorinen 《木材化学与工艺学杂志》2016,36(5):318-328
An oxygen delignified eucalyptus kraft pulp was bleached by applying a catalytic amount of a tertiary amine, 1,4-diazabicyclo[2,2,2]octane, and hypochlorous acid at varying pH, temperature, and time. The bleaching filtrate was analyzed for chloroform and AOX and the pulp for residual lignin, hexenuronic acid, and OX. In comparison with chlorine dioxide bleaching, the novel catalytic bleaching (pH < 6) generated only traces of chloroform and low contents of AOX and OX. Separate catalytic oxidations of authentic hexenuronic acid showed that it was a major precursor of chloroform. The results demonstrate a practical way to reduce organochlorine formation in pulp bleaching and provide new understanding on the reaction pathways that yield chloroform. 相似文献
945.
Tuning of Cloud Point by the Nature of Surfactant Headgroup: Influence of Counterion and Additives 下载免费PDF全文
Sanjay Kumar Yadav Ran Bahadur Yadav Sanjeev Kumar 《Journal of surfactants and detergents》2016,19(5):1063-1069
Work was performed to distinguish the role of sulfonate (–SO3 ?) and sulfate (–OSO3 ?) with respect to the micellization and clouding phenomenon in ionic surfactant solutions. The clouding phenomenon is a recent addition to the conventional one observed with nonionic surfactants. Three ionic surfactants [sodium dodecylsulfate (SDS), sodium dodecylbenzenesulfonate (SDBS), and sodium dodecylsulfonate (SDSo)] are chosen and the effects of added tetra-n-pentylammonium bromide (TPeAB) and benzyl tributylammonium bromide (BTAC) have been studied on micellization and clouding behaviors in aqueous solution. Based on critical micelle concentration (CMC) and cloud point (CP) measurements, the following order has been observed: SDBS < SDS < SDSo. Though both SDBS and SDSo contain sulfonate groups, they are found at the two ends of the ordering. Therefore, the role of the phenyl ring is also having importance in clouding phenomena. For a typical surfactant, TPeAB was found to be more effective than BTAC. Based on the CP studies, two compositions of SDSo + TPeAB/BTAC were chosen and the effects of different additives (carbohydrate, amino acid, and l-ascorbic acid) on the CP were investigated. Additive may either decrease or increase CP, depending on the structure of the counterion or additive. The present work shows a few novelties: (1) headgroup/counterion dependence of CP and (2) hydrophobicity of counterion/surfactant has an important bearing on the phenomenon. The data can be utilised in improving cloud point extraction methodologies (CPEMs). 相似文献
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Jacob Mahaffey David Adam Andrew Brittan Mark Anderson Kumar Sridharan 《Oxidation of Metals》2016,86(5-6):567-580
The corrosion of Ni-based alloy Haynes 230 in supercritical carbon dioxide at temperatures of 650 and 750 °C at a pressure of 20 MPa was investigated. In high-purity research grade CO2, the corrosion performance of the alloy was excellent with a thin, uniform, protective chromium-rich oxide layer forming on the surface. Introduction of 10 and 100 ppm O2 impurity in the CO2 environment noticeably enhanced oxidation with evidence of oxide spallation and nodule formation. In these oxygen impurity added tests, increased oxidation led to subsurface voids due to the more rapid outward diffusion of chromium as well as intergranular alumina and chromia. The oxygen concentration at the inlet and the outlet of the autoclave was measured and used to support the results of characterization of the surface oxide to develop a more holistic understanding of the role of oxygen impurity on the corrosion process. In all cases, there some carbon was observed, which manifested as slightly higher concentration of chromium–carbide phase at the grain boundaries compared to the unexposed alloy. 相似文献
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C. P. Sudheesh Kumar C. Sujatha Shankar Krishnapillai 《Journal of Mechanical Science and Technology》2016,30(10):4479-4487
Dynamic responses of simply supported non-uniform beams traversed by a moving oscillator are analysed in this paper. An approximate analytical method based on Rayleigh-Ritz (R-R) formulation is developed. The fundamental approximate mode obtained from R-R method is used in the present formulation to determine the responses of the beam and the oscillator. Effects of surface irregularities on the displacement and acceleration responses of the beam and the vehicle are also analysed. The results are compared with those obtained using Finite element method (FEM). A numerical example is provided to illustrate the validity of the present method which shows that the proposed method is simple, computationally more efficient compared to FEM and gives fairly good results. Though the single-mode approach used in the present paper is a classical one and numerous studies on the responses of uniform beams under moving loads have been reported in the past, its application to non-uniform beams (for which there does not exist any closed form expression for mode shapes) under a moving load, especially a moving oscillator, is presented for the first time. 相似文献
948.
In this communication, new composite desiccant materials having 37% concentration of CaCl2 have been compared for water production from atmospheric air. The vermiculite–saw wood, jute and burnt-clay have been used as host materials and CaCl2 as a hygroscopic salt. All the desiccant materials have been tested with the solar glass desiccant box type system (SGDBS) with a collector area of 0.36?m2. Design parameters for water production are: height of the glass from the desiccant bed to be 0.22?m, an inclination angle of 30°, the effective thickness of the glass as 3?mm and the number of glazing is single. It has been found that on the experimental day, the maximum amount of fresh water generated by the vermiculite–saw wood/CaCl2 is 130?ml/kg/day. 相似文献
949.
Energy demand is the hot topic of all developing and developed countries. Energy demand has been increasing day by day at a high rate. So, it is necessary to find an alternative solution that is eco-friendly. Biodiesel can be the alternative solution for this problem. The main purpose of this paper is to test the engine performance and emission parameters of a diesel engine using pure cinnamon oil blended with diesel and using cerium oxide as a catalyst. The parameters measured are brake power, brake thermal efficiency, specific fuel conception, CO2, CO, NOx and HC. 相似文献
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