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Criteria for authentic olive oils were developed from isocratic high-performance liquid chromatography analyses of 99 olive oils from the major Mediterranean producers in the 1983–1986 crop years. Authentic olive oils include extra virgin, virgin and pure or refined oils, but exclude all reesterified and adulterated oils. The extra virgin through pure grades will have a combined area for the LOO (C18:2C18:1C18:1), LOP (C18:2C18:1C16:0), OOO (C18:1C18:1C18:1), POO (C16:0C18:1C18:1), POP (C16:0C18:1C18:1), and SOO (C18:0C18:1C18:1) peaks between 82.0 and 92.6% of the total area (L, linoleic; O, oleic; P, palmitic; S, stearic). Authentic oils will have ratios of LOO/LOP and OOO/POO that coincide with a line defined by OOO/POO=0.7844(LOO/LOP)+0.0968; correlation coefficient is 0.885. Authentic oils will not have a trilinolein (LLL) peak over 0.5% in area. Neither triolein (OOO) nor any other single peak suffices to characterize an olive oil sample as one of the authentic grades.  相似文献   
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Summary The room temperature conductivity of lithium salts dissolved in polyethylene oxide, proposed as polymer electrolytes, is shown to decrease drastically upon storage. The crystallization process, which is responsible for that ageing, can be blocked, if two further components are added : an elastomer copolymer butadiene-acrylonitrile and a macromer of polyoxyethylene. In addition, a crosslinking process must be carried out.  相似文献   
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Two simple methods are presented for the characterization of inelastic power law fluids from falling sphere data. The methods involve the application of shear rate or shear stress correction factors which have been derived theoretically using Slattery's solution for creeping flow about spheres. Flow curves obtained using these methods are in excellent agreement with those measured on a Weissenberg rheogoniometer for 0.83 ≤ n ≤ 1.0. The experimentally determined drag coefficients are found to be in good agreement with the predictions of Slattery's creeping flow first approximation solution. The wall correction factors of Faxen and Francis appear to be valid for inelastic non-Newtonian fluids up to a diameter ratio of at least 0.08.  相似文献   
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德惠断陷下白垩统登娄库组、营城组、沙河子组储层物性差,勘探风险大.利用岩心观察、铸体薄片鉴定、扫描电镜分析、黏土X线衍射分析等方法,分析储层基本特征、储层成岩作用和控制因素.结果表明:德惠断陷下白垩统碎屑岩储层成分成熟度和结构成熟度较低,储层孔隙类型主要有残余原生孔、次生孔和混合孔,储层物性和孔隙结构较差;压实作用是导致储层物性变差的主要原因,溶蚀作用改善储层物性;纵向上发育2个次生孔隙带,主要形成于中成岩期,次生孔隙带的形成与有机质生烃排酸和断裂有关.研究结果为德惠断陷下白垩统进一步油田勘探提供地质依据,对其他地区类似储层研究有一定借鉴意义.  相似文献   
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In this article we propose a new method to estimate ocean mesoscale structures of the surface current velocity by processing sea surface satellite images. Assuming that the intensity level can be described by a transport-diffusion equation, the proposed approach is based on variational assimilation of image observations within a simple transport-diffusion model. This approach permits to retrieve the current velocity field from a sequence of satellite images. Results of processing synthetic data and real NOAA-AVHRR satellite images are presented and commented.  相似文献   
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Abstract— The primary goal of this study was to find a measurement method for motion blur which is easy to carry out and gives results that can be reproduced from one lab to another. This method should be able to also take into account methods for reduction of motion blur such as backlight flashing. Two methods have been compared. The first method uses a high‐speed camera that permits us to directly picture the blurred‐edge profile. The second one exploits the mathematical analysis of the motion‐blur formation to construct the blurred‐edge profile from the temporal step response. Measurement results and method proposals are given and discussed.  相似文献   
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Oculo-dento-digital syndrome (SODD) as defined by Meyer-Schwickerath in 1957 is a rare entity (84 cases) which belongs to ectodermal dysplasias. It consists of: the characteristic features (long face, pinched nose); syndactyly; ocular, dental and bone abnormalities. This entity is usually transmitted on the autosomal dominant mode. We report two cases (a mother and daughter) with polymalformations which we classed as SODD. Furthermore, agenesis of lacrimal duct and genitourinary abnormalities were noted. The mother had a very particular complex hair shaft dysplasia (incomplete pili torti, "tiger tail" aspect, fractures) with alopecia since she was fifteen years old. The daughter's hair was normal at birth. In SODD, fine and sparse hair is often observed (44 p. 100). Only one patient had hair shaft investigation under polarized light: pili annulati and monilethrix were described but not found in our cases. These two reports incite to the systematic hair shaft study in SODD as other ectodermal dysplasia syndromes.  相似文献   
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