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61.
[reaction: see text] A new method for synthesizing phenanthridine and its related compounds was developed using the condensation of o-phenylaniline and its homologues with cyclic ketones under hydrothermal conditions.  相似文献   
62.
We use an all-optical trap to confine a strongly attractive two-state mixture of lithium fermions. By measuring the rate of evaporation from the trap, we determine the effective elastic scattering cross section 4pia(2) to show that the magnitude of the scattering length |a| is very large, in agreement with predictions. We show that the mixture is stable against inelastic decay provided that a small bias magnetic field is applied. For this system, the s-wave interaction is widely tunable at low magnetic field, and can be turned on and off rapidly via a Raman pi pulse. Hence, this mixture is well suited for fundamental studies of an interacting Fermi gas.  相似文献   
63.
Dibromoacetyl benzene derivatives on condensation with thiourea give 2-amino-4-arylthiazoles instead of the expected 2-amino-4-aryl-5-bromothiazoles. Attempts have been made to find the reaction pathway.  相似文献   
64.
1,5,6,10b-Tetrahydropyrrolo[2,1-alpha]isoquinolin-3(2H)-ones 17a,b, 17d,e, and 5,12b-dihydroisoindolo[1,2-alpha]isoquinolin-8(6H)-ones 22a-e were prepared by intramolecular cyclizations of 1-(2-arylethyl)-5-benzotriazolyl-pyrrolidin-2-ones 15a,b, 15d,e, and 3-benzotriazolyl-2-(2-arylethyl)-1-isoindolinones 20a-e, respectively, in the presence of titanium chloride. Products from chiral amines were obtained with stereoselectivities of > or = 94%.  相似文献   
65.
C-field cosmological models based on Hoyle-Narlikar theory with variable gravitational constant G in the frame work of FRW (Friedmann-Robertson-Walker) space–time for positive and negative curvatures are investigated. To get the deterministic solutions in terms of cosmic time t, we have assumed G=R n and discussed for n=−1, −2, R being scalar factor. In both the cases, creation field C increases with time, the gravitational constant G and matter density (ρ) decrease with time in the model (21). In the model (41) G decreases with time and matter density (ρ) is constant. The other physical aspects of the models are also discussed.  相似文献   
66.
A comparative study of thermoresponsive poly(N-isopropylacrylamide)(PNIPAAm)-chitosan (CS)-based magnetic nanohydrogels (MNHGs) encapsulating functionalized Fe3O4 nanoparticles (NPs) in terms of the parameters governing their suitability for real hyperthermia is reported. Iron oxide NPs functionalized with (a) citric acid (CA-Fe3O4), (b) ethylenediamine (Amine-Fe3O4) and (c) dimercaptosuccininc (DMSA-Fe3O4) have been synthesized and their encapsulation into MNHGs was obtained through physical encapsulation method. The structural characterizations of synthesized materials include X-ray diffraction, FT-IR, TGA, ICP-AES and X-ray photoelectron spectroscopy (XPS). Encapsulation of the functionalized NPs into MNHGs were observed in TEM micrographs, while SEM and AFM micrographs confirmed their spherical morphology (~250–300 nm). Lower critical solution temperature (LCST) variation was measured by UV–visible spectrophotometer and differential scanning calorimetry (DSC). MNHGs exhibited sufficient magnetization and heating ability for hyperthermia. Typically, hydrogels containing CA-Fe3O4 (50 mg/ml) raised the temperature of the medium to 43 °C, a suitable dose for in vivo application in tumor-bearing mice.  相似文献   
67.
Clay from the Purmandal area of J&K State was separated into its different size fractions by the method of sedimentation and with Sharple's super centrifuge process. Dilatometric studies were performed on each clay fraction; the results obtained from the dilatation curves are discussed in detail. The results revealed that the finer fraction of clay is bentonitic in nature, whereas the other fractions are felsphatic and micaceous in nature.  相似文献   
68.
The issues we address here are – How should a firm (e.g. Internet service provider (ISP)) that is capable of collecting personal information (browsing information, purchase history, etc.) about consumers, price its service, given that consumers vary in their valuation for privacy, and also vary in terms of the value of their personal information to a third party (firms that need consumer information)? Should the firm have a blanket policy of never collecting, or a policy of always collecting and revealing information? Surprisingly we find that in some cases the collector of information may be no worse off in the asymmetric information case than in the full information case. The paper provides a justification for the strategy of some firms such as ISP’s which never collect information and also for the strategy of other firms, like grocery stores that do. We also find that it is non-optimal for the firm to design contracts where the consumer can choose an intermediate level of privacy.  相似文献   
69.
JPC – Journal of Planar Chromatography – Modern TLC - Adensitometric HPTLC method has been established for analysis in alcohol extracts of the seeds and leaves of Achyranthes aspera L....  相似文献   
70.
In recent years, rapid increase has been observed in the population of microbes that are resistant to conventionally used antibiotics. Antifungal drug therapy is no exception and now resistance to many of the antifungal agents in use has emerged. Therefore, there is an inevitable and urgent medical need for antibiotics with novel antimicrobial mechanisms. Aspergillus glaucus is the potential cause of fatal brain infections and hypersensitivity pneumonitis in immunocompromised patients and leads to death despite aggressive multidrug antifungal therapy. In the present article, we describe the antifungal activity of multifunctional core-shell Fe3O4-Ag nanocolloids against A. glaucus isolates. Controlled experiments are also carried out with Ag nanocolloids in order to understand the role of core (Fe3O4) in the antifungal action. The minimum inhibitory concentration (MIC) of nanocolloids is determined by the micro-dilution method. MIC of A. glaucus is 2000 μg/mL. The result is quite promising and requires further investigations in order to develop a treatment methodology against this death causing fungus in immunocompromised patients.  相似文献   
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