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71.
Background
Dihydrolinalool and terpineol are sources of fragrances that provide a unique volatile terpenoid alcohol of low toxicity and thus are widely used in the perfumery industry, in folk medicine, and in aromatherapy. They are important chemical constituents of the essential oil of many plants. Previous studies have concerned the biotransformation of limonene by Pseudomonas putida. The objective of this research was to study biotransformation of myrcene by Pseudomonas aeruginosa. The culture preparation was done using such variables as different microbial methods and incubation periods to obtain maximum cells of P. aeruginosa for myrcene biotransformation.Results
It was found that myrcene was converted to dihydrolinalool and 2,6-dimethyloctane in high percentages. The biotransformation products were identified by Fourier-transform infrared spectroscopy (FT-IR), ultraviolet (UV) analysis, gas chromatography (GC), and gas chromatography-mass spectroscopy (GC-MS). Comparison of the different incubation times showed that 3 days was more effective, the major products being 2,6-dimethyloctane (90.0%) and α-terpineol (7.7%) and comprising 97.7%. In contrast, the main compounds derived for an incubation time of 1.5 days were dihydrolinalool (79.5%) and 2,6-dimethyloctane (9.3%), with a total yield of 88.8%. 相似文献72.
73.
Effect of heavy cation doping (Ca2+ at the A-site) on the thermal properties of perovskite LaMnO3 has been investigated using the Rigid Ion Model (RIM)). As strong electron-phonon interactions are present in these compounds,
the lattice part of the specific heat deserves proper attention. The specific heat of magnetoresistance compound La0.25Ca0.75MnO3 as a function of temperature (10 K ≤ T ≤ 300 K) is reported. Our results on specific heat are in good agreement with the measured values of specific heat at lower
temperatures. In addition, the results on the cohesive energy (ϕ), molecular force constant (f), Restrahalen frequency (ν
0), Debye temperature (Θ
D) and Gruneisen parameter (γ) are also discussed.
相似文献
74.
S. Rai Choudhury A. S. Cornell Naveen Gaur 《The European Physical Journal C - Particles and Fields》2008,58(2):251-259
Flavor changing neutral current (FCNC) decays of the B-meson are a very useful tool for studying possible physics scenarios beyond the standard model (SM), where of the many FCNC
modes radiative, purely leptonic and semi-leptonic decays of the B-meson are relatively clean tests. Within this context, the BELLE collaboration has measured the process B→K
*
γ and also searched for the B→K
1(1270)γ process. Theoretical analyses of these processes are yielding similar values of the relevant form factors. In this work we
have used this upper bound in studying the angular correlations for the related semi-leptonic decay mode B
−→K
1−(1270)(→ρ
0
K
−)ℓ
+
ℓ
−, where we have used the form factors that have already been estimated for the B→K
1(1270)γ mode. Note that the additional form factors that are required were calculated using large energy effective theory (LEET). 相似文献
75.
PVDF + BaZrO3 electroactive nanocomposite thin film has been prepared by solution casting method. The structural analysis was carried out by using x-ray diffraction pattern and atomic force microscopy (AFM). Generally, the performance of dielectric capacitors toward higher energy density and higher operating temperatures has been drawing increased interest. In this regard, the present study was focussed on the fabrication and characterization of PVDF + BaZrO3 electroactive nanocomposites in view of enhancing the energy density at elevated temperature. Cole-Cole plot is an agreement with multiple relaxation process in electroactive nanocomposites. Dielectric energy storage performance is assessed for PVDF nanocomposites with different wt% of BaZrO3 at different frequencies and temperature. It has been observed that with increase of temperature, the permittivity increased while the energy density slightly decreased but significantly higher than pure polymer PVDF. A high energy density of 6.88 J/cm3 was obtained for BaZrO3 electroactive nanocomposites at 50 °C and 5.06 J/cm3 at 70 °C. Overall, the testing results indicate that using nanocomposites of PVDF and BaZrO3 as a dielectric component is promising for implementation to preserve high energy density values up to temperatures of 70 °C.The enhancement of dielectric permittivity and the energy density is attributed due to increase of interracial charge density. The effect of BaZrO3 nanoparticles in energy density of PVDF is first time reported. 相似文献
76.
Though the predictions of the standard model (SM) are in excellent agreement with experiments, there are still several theoretical
problems associated with the Higgs sector of the SM, where it is widely believed that some new physics will take over at the
TeV scale. One beyond the SM theory which resolves these problems is the Little Higgs (LH) model. In this work we have investigated
the effects of the LH model on γγ → γγ scattering [1].
相似文献
77.
Nupinderjeet Kaur N.K. Gaur R.K. Singh 《Journal of Physics and Chemistry of Solids》2007,68(12):2247-2251
The thermodynamic behavior of carbon doped MgB2 has been studied using a rigid ion model (RIM). The model potential consists of the long-range Coulomb, the short-range repulsive and the van der Waals interactions. This model has successfully explained the cohesive and thermodynamic properties of Mg(B1−xCx)2 (x=0.0, 0.02, 0.05, 0.075, 0.1, 0.2). The properties studied are the cohesive energy, molecular force constant, Restrahlen frequency, compressibility, Debye temperature and Gruneisen parameter. Our results on Restrahlen frequency and Debye temperature are in reasonably good agreement with the available experimental data. In addition, we have computed the specific heat Cp for Mg(B1−xCx)2 (x=0.2) as a function of temperature T in the range 16 K?T?1000 K. We have also shown the variation of specific heat Cp with doping concentration at room temperature (300 K). The calculated specific heat Cp for Mg(B1−xCx)2 (x=0.2) in the temperature range 16 K?T?22 K for which experimental results are available, agrees pretty well with the experimental data. 相似文献
78.
Umesh Gaur Miao -Yong Cao R. Pan B. Wunderlich 《Journal of Thermal Analysis and Calorimetry》1986,31(2):421-445
It is shown that heat capacities of linear macromolecules consisting of all-carbon single-bonded backbones can be calculated from the appropriate contributions of substituted carbon atoms to a precision of about – 0.2±2.5% (155 data points), which is similar to the experimental precision. Heat capacity contributions of 42 groups are given over the full range of measurement and reasonable extrapolation. The quality of the addition scheme is tested on 16 series of measurements on homopolymers, copolymers and blends. The addition scheme works for all these different states of aggregation of the constituent groups. The basis of the addition scheme is discussed.
On leave from the University of Science and Technology of China, Hefei, Peoples Republic of China.
This work was supported through the many years it took to assemble the needed experimental data by the National Science Foundation,-Polymers Program, Grant # DMR 8317097. 相似文献
Zusammenfassung Es wird gezeigt, daß Wärmekapazitäten von aus Hauptketten mit ausschließlich C-C-Einfachbindungen bestehenden Makromolekülen aus geeigneten Beiträgen der substituierten Kohlenstoffatome mit einer Genauigkeit bis etwa –0.2±2.5% (155 Datenpunkte) berechnet werden können, was der experimentellen Genauigkeit nahe kommt. Wärmekapazitätsbeiträge von 42 Gruppen wurden über den vollen Meßbereich hinweg und durch sinnvolle Extrapolation bestimmt und angegeben. Die Zuverlässigkeit des Additionsschemas wurde in 16 Meßreihen an Homopolymeren, Kopolymeren und Mischungen getestet. Das Additionsschema ist für alle diese verschiedenen Anordnungen der konstitutionellen Gruppen zutreffend. Die Grundlagen des Additionsschemas werden diskutiert.
, , , , , –0,2 ±2,5% (155 ), . 42 - . 16 , . . .
On leave from the University of Science and Technology of China, Hefei, Peoples Republic of China.
This work was supported through the many years it took to assemble the needed experimental data by the National Science Foundation,-Polymers Program, Grant # DMR 8317097. 相似文献
79.
The oxidation of various monohydric alcohols with pentavalent vanadium in sulphuric acid medium is described. Optimum conditions for quantitative oxidation and the reaction mechanisms are discussed. 相似文献
80.
Saran Dayal Sagar Rohan Gaur Mulayam Singh 《Journal of Thermal Analysis and Calorimetry》2019,136(4):1687-1687
Journal of Thermal Analysis and Calorimetry - In the original publication of the article, Tables 1 and 2 were swapped. The correct versions are given below. The original article has been... 相似文献