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61.
Let U2n denote the quasi-split unitary group over 2n variables with respect to a quadratic extension E/F of p-adic fields. In this short note, we relate GLn(F)-distinction of ladder representations of GLn(E) with irreducibility of its Siegel parabolic induction in U2n.  相似文献   
62.
63.
Dihydronaphthoquinolines are relatively rare polycyclic heterocyclic compounds. We wish to report a simple and convenient preparative method for hitherto unknown compounds with these new structural features. 6-methoxy tetralone1 (I) 3.5g (.02 mole) in 3 ml DMF was added slowly to 4.6g (.02 mole) of POCl3 in 3ml DMF at 0°C. The mixture was stirred for 5 hrs. and the temp. was then gradually raised from 0° to 60–65°C. The resultant complex was treated with aq. sodium acetate solution till pH5–6 was reached. The extract on usual purification, furnished 3.2g (80°%.) of 1-chloro, 6-methoxy, 1,2,3,4 tetrahydro naphthalene-2-aldehyde(II)+2  相似文献   
64.
We study the structure of a uniformly randomly chosen partial order of width 2 on n elements. We show that under the appropriate scaling, the number of incomparable elements converges to the height of a one dimensional Brownian excursion at a uniformly chosen random time in the interval [0, 1], which follows the Rayleigh distribution.  相似文献   
65.
The scaled factorial moments and the multifractal moments have been investigated in different??-intervals to study the dynamical fluctuation of pions produced in 200 AGeV32S-Ag/Br interaction. In order to investigate the detail characteristics of intermittency behaviour, theF-moments are extracted up to the eighth order of moments in differentM-intervals. The analysis indicates a non-thermal phase transition and different regime of particle production during the hadronisation process.  相似文献   
66.
Abstract

Selective interpolymer complexation has been studied between methacrylic acid-methacrylamide copolymer and some complementary polymers such as poly(methacrylamide), poly(vinyl pyrrolidone), and poly(ethylene oxide). The relative order of complexation ability of the various nonionic polymers has been interpreted on the basis of the nature of interactions between different units of polymers. Configurational environment and neighboring group influences seem to affect interpolymer complex formation.  相似文献   
67.
A phenolic copolymer has been grafted with oligomers of different chain lengths. Polymer-polymer complexation has been studied between graft copolymers and nonionic polymers, such as polyvinyl pyrrolidone) and poly(ethylene oxide), in an acetone-methanol mixture by several methods, e.g., viscosity, conductance, and apparent pH measurements. A distinct stepwise complexation between PVP and graft copolymers has been observed. The length of the side chain also seemed to influence interpolymer complex formation. Some of these observations have been interpreted with reference to the actual structure of the graft copolymers.  相似文献   
68.
A phenolic copolymer has been prepared by copolymerization of p-chlorophenol, p-cresol, and formaldehyde in the presence of acid catalyst. The copolymer was partially and completely dehalogenated by a standard method. The dehalogenated copolymer chain had a random distribution of reactive positions which were originally occupied by Cl atoms. Some substituted monomers, oligomers of known structure and molecular weight, and basic polymer chains have been grafted at these reactive positions. The halogen percentage of the grafted copolymers could be calculated on the assumption that all the available reactive positions are attached to the respective units. Reasonably good agreement has been found between the calculated and observed amount of halogen percentage in the grafted copolymers.  相似文献   
69.
We have developed a rapid and sensitive method for immunomagnetic separation (IMS) of Salmonella along with their real time detection via PCR. Silica-coated magnetic nanoparticles were functionalized with carboxy groups to which anti-Salmonella antibody raised against heat-inactivated whole cells of Salmonella were covalently attached. The immuno-captured target cells were detected in beverages like milk and lemon juice by multiplex PCR and real time PCR with a detection limit of 104 cfu.mL?1 and 103 cfu.mL?1, respectively. We demonstrate that IMS can be used for selective concentration of target bacteria from beverages for subsequent use in PCR detection. PCR also enables differentiation of Salmonella typhi and Salmonella paratyphi A using a set of four specific primers. In addition, IMS—PCR can be used as a screening tool in the food and beverage industry for the detection of Salmonella within 3–4 h which compares favorably to the time of several days that is needed in case of conventional detection based on culture and biochemical methods.
The method uses silica coated magnetic nanoparticles immobilized with anti-Salmonella antibody for immunomagnetic separation of Salmonella from beverages followed by detection by multiplex PCR (mPCR) and real time PCR (qPCR). This methodology contributes to rapid screening and accurate detection of Salmonella contaminations in beverages.  相似文献   
70.
A number of ortho -cyclohexenyl phenols 2(a–i) have been cyclised by treatment with one equivalent of m-chloroper-oxybenzoic acid in refluxing benzene for 4 h to furnish linearly fused 1-hydroxy-1,2,3,4,4a,9a-hexahydrodibenzofurans 3(a–i) (70–80%) and bicyclic 3-hydroxy-1,3-ethanochromans 4(a–f) (10–20%). Products 3(a–i) were oxidised with 2,3-dichloro-5,6-dicyano-1,4-benzoquinone (excess) in refluxing dry xylene for 6 h to give 2,3-dihydrodibenzofuran-1 (2H)-ones 6(a–i) (85–95%).

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