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991.
Various 2-phenylimidazo[4,5-f][1,10]phenanthrolines were synthesized from potassium ferro-cyanide trihydrate(KFCT) complex catalyzed three component reaction of 1,10-phenanthroiine-5,6-dione,aromatic aldehydes and ammonium acetate at room temperature in excellent isolated yield.This is a simple and straight forward,high yielding,not involving any hazardous or expensive catalyst method.  相似文献   
992.
Clostridium difficile continues to cause infections in healthcare and other settings. Its spores survive well indoors and require sporicidal chemicals for infection control. However, proper testing of disinfectants is impeded due to difficulties in obtaining viable spores of high enough quality and titers to meet current regulations for sporicidal claims. A new liquid medium (Clospore) has been developed, based on a systematic review of the compositions of 20 other available media. C. difficile spores grown in the new medium and treated with a mixture of lysozyme and trypsin yielded final suspensions with > 10(9) CFU/mL of viable spores, with a purity of > 91% as tested by spore-staining and phase-contrast microscopy. The spores showed a biological decay rate of about 0.1 log10/month when dried on metal disks and stored indoors (air temperature 23 +/- 2 degrees C; relative humidity 52.76 +/- 15.08%). Heating the purified spore suspensions to 70 degrees C for 10 min to inactivate any vegetative cells showed no spore activation or inactivation. The spores could be stored for at least 14 months either refrigerated (4 degrees C) or frozen (-20 or -80 degrees C) in 50% (v/v) ethanol with virtually no loss in viability. The resistance of the enzyme-treated spores to three levels of sodium hypochlorite (1000, 3000, and 5000 ppm), using a standardized quantitative carrier test, was almost identical to that of the spores concentrated by centrifugation alone. The described procedure has been successfully applied to four standard (ATCC) and six clinical strains of C. difficile.  相似文献   
993.

Abstract  

Iron doped titanium oxide nanotubes (TNTs) were synthesized by hydrometallurgical process using a mixture of NaOH and methanol as precipitating and reducing agents, respectively. Nanotubes with a high purity and good aspect ratio are produced as indicated by X-ray diffraction (XRD), scanning electron microscopy (SEM), and transmission electron microscopy (TEM). The characterization data show that high-purity Fe-doped TNTs with diameter around 12–14 nm and length around 400–460 nm are synthesized using this process. The TNTs are found to be in the anatase phase and as the Fe doping is increased, the conductivity increases. UV/VIS data suggest the red shift in the peaks and increased absorption on the account of doping. The studies on microcosmic magnetic properties of the sample with 15% Fe content indicate the component of magnetic moment in the axial direction of nanotubes. Doping of Fe is found to considerably affect the crystallite size, Curie temperature (T c), DC conductivity (σ), and Raman shifts.  相似文献   
994.
Molecular Diversity - Alzheimer’s disease (AD) is now ranked as the third leading cause of death after heart disease and cancer. There is no definite cure for AD due to the multi-factorial...  相似文献   
995.
Time series models have been used to make predictions of stock prices, academic enrollments, weather, road accident casualties, etc. In this paper we present a simple time-variant fuzzy time series forecasting method. The proposed method uses heuristic approach to define frequency-density-based partitions of the universe of discourse. We have proposed a fuzzy metric to use the frequency-density-based partitioning. The proposed fuzzy metric also uses a trend predictor to calculate the forecast. The new method is applied for forecasting TAIEX and enrollments’ forecasting of the University of Alabama. It is shown that the proposed method work with higher accuracy as compared to other fuzzy time series methods developed for forecasting TAIEX and enrollments of the University of Alabama.  相似文献   
996.
The electronic properties of a-Si:H vary with hydrogen passivation of dangling bond defects. It appears this effect is also operative in semiconducting amorphous hydrogenated boron carbide (a-B5C:H). Therefore, the ability to quantify the amount of hydrogen will be key to development of the materials science of a-B5C:H. The results of an initial investigation probing the ability to quickly correlate hydrogen concentration in a-B5C:H films with infrared spectroscopy are reported. a-B5C:H thin films were growth on Si (1 1 1) substrates by plasma-enhanced chemical vapor deposition (PECVD) using sublimed orthocarborane and argon as the precursor gas. Nuclear reaction analysis (NRA) was performed to quantify the atomic concentration of H in the a-B5C:H films. While the observed vibronic structure does not show stretches due to terminal C–H or bridging B–H–B, analysis of the terminal B–H stretch at ~2570 cm?1 gives a proportionality constant of A = 2 × 1022 cm?2. We conclude that the methods previously developed for correlating H concentration to infrared data in a-Si:H are similarly viable for a-B5C:H films.  相似文献   
997.
Our present investigation aims at the synthesis and application of new, symmetric bridged bis-pyrazolone based acid dyes. The bis-pyrazolone compounds were accomplished from bis- hydrazine of 4,4′-Diaminostilbene-2,2′-disulfonic acid and ethyl acetoacetate. The bis-pyrazolones have been coupled with diazonium salts of o-hydroxyl aromatic amines which resulted in ligand dyes. The intermediate ligand dyes were treated with 3d transition metals to achieve the targeted metal complex acid dyes. The structures of investigated compounds were confirmed with the help of spectroscopic techniques. Dyes were applied on leather and their application parameters including their light fastness, wash fastness and rubbing fastness were determined.
Graphical Abstract Symmetric brymmetric Bridged bis-Pyrazolone based Metal Complex Acid
  相似文献   
998.
An approximate solution for the nuclear Hulthén plus atomic Hulthén potentials is constructed by solving the associated Volterra integral equation by series substitution method. Within the framework of supersymmetry-inspired factorisation method, this solution is exploited to construct higher partial wave interactions. The merit of our approach is examined by computing elastic scattering phases of the \(\alpha {-}\alpha \) system by the judicious use of phase function method. Reasonable agreements in phase shifts are obtained with standard data.  相似文献   
999.
Alteration of insect growth regulators by the action of inhibitors is becoming an attractive strategy to combat disease-transmitting insects. In the present study, we investigated the larvicidal effect of 1,2,3-triazolyl-pyrimidinone derivatives against the larvae of the mosquito Anopheles arabiensis, a vector of malaria. All compounds demonstrated insecticidal activity against mosquito larvae in a dose-dependent fashion. A preliminary study of the structure–activity relationship indicated that the electron-withdrawing substituent in the para position of the 4-phenyl-pyrimidinone moiety enhanced the molecules’ potency. A docking study of these derivatives revealed favorable binding affinity for the sterol carrier protein-2 receptor, a protein present in the intestine of the mosquito larvae. Being effective insecticides against the malaria-transmitting Anopheles arabiensis, 1,2,3-triazole-based pyrimidinones represent a starting point to develop novel inhibitors of insect growth regulators.  相似文献   
1000.
Dihydrouracil presents a crucial intermediate in the catabolism of uracil. The vital importance of uracil and its nucleoside, uridine, encourages scientists to synthesize novel dihydrouracils. In this paper, we present an innovative, fast, and effective method for the synthesis of dihydrouracils. Hence, under mild conditions, 3-chloroperbenzoic acid was used to cleave the carbon–sulfur bond of the Biginelli hybrids 5,6-dihydropyrimidin-4(3H)-ones. This approach led to thirteen novel dihydrouracils synthesized in moderate-to-high yields (32–99%).  相似文献   
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