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51.
In the first part of this review, the authors give a survey on the literature of vibrational spectroscopy of phenol, phenol derivatives, and other phenolic componds from the last decade of the last century through today. The classical and modern methods of vibrational spectroscopy are also introduced and a glossary is included to aid comprehension. The second part deals with the literature regarding the importance of vibrational spectroscopy in the investigation and identification of phenolic compounds in natural substances, the application of vibrational spectroscopy in composite and synthetic polymer chemistry, and following of chemical processes and investigating their resulting products. Vibrational spectroscopy is a very good tool for determination of molecular structures and is important in chemical analysis and in the chemical industry. 相似文献
52.
C. Pal P. S. Wheatley H. El. Mkami D. J. Keeble R. E. Morris Olav Schiemann 《Applied magnetic resonance》2010,37(1-4):619-627
For medical purposes, materials are required that store and target specifically deliver exogenous nitric oxide (NO). Partially zinc-exchanged Na-LTA (Linde type A) zeolite (Zn-LTA) has high potential in this respect due to its non-toxicity and adsorption capacity for NO. In contrast to NO adsorbed to LTA zeolites prepared for catalytic purposes, lower dehydration temperature prior to NO adsorption is used to achieve a balance between production cost and high activity. In order to study the interaction of NO with the metal sites in the samples prepared under these medical conditions, continuous-wave X-band electron paramagnetic resonance has been applied. In contrast to Na-LTA with only one weakly interacting NO monomer, three different monomers, having stronger interaction to the metal sites than in Na-LTA, were observed in Zn-LTA. To improve the storage capacity of Zn-LTA, higher dehydration temperatures would be necessary. 相似文献
53.
S.A. Safwan A.S. Asmaa Nagwa El meshed M.H. Hekmat TH.M. El-Sherbini S.H. Allam 《Superlattices and Microstructures》2010
Within the effective mass approximation, we investigated theoretically the ground-state energy of a single particle and the binding energy of the neutral donor impurity (D0) affected by a lateral electric field in a parabolic quantum dot (QD). The results show that the electron and the hole ground-state energy and the band to band transition energies shift to lower values (red shift) by increasing the field intensity. The quantum Stark shift (QSS) for the electron increases rapidly in the quasi spherical QD (QSQD) by increasing the lateral field, whereas for the hole it increases monotony. In the cylindrical QDs (CQDs), we found that the QSS for electron and hole increase monotonically. The quantum size, lateral electric field and impurity position effect on the binding energy of neutral donor (D0) is studied. Unexpected behavior of D0 in quantum well limit (QW), the binding energy of D0 is increasing (blue shift) with increasing QD radius R at the presence of a lateral electric field. It appears that for a fixed size of the QD, the off-center binding energy decreases when the impurity ion is displaced from the center to the QD borders, while it is shifted to lower energy with increasing the field. 相似文献
54.
Nareman Harpy Abdel-Rahman Mohamed A. E. Sallam Abdelsattar M. El Dabour Sameh 《Physics of Particles and Nuclei Letters》2020,17(2):253-259
Physics of Particles and Nuclei Letters - Gamma spectrometry is applied for measurement of natural radioactivity by Hyper-pure germanium (HPGe) systems during the application of bioleaching optimum... 相似文献
55.
Today, analyzing of sound pressure level and frequency is considered as an important index in human society. Sound experts believe that analyzing of these parameters can help us to better understanding of work environments. Sound measurements and frequency analysis did to fix the harmful frequency in all sections in Shiraz gas power plant with sound analyzer model BSWA 308. The sound pressure levels (LP) and the one and one-third octave band were continuously measured in A and C weighting networks and slow mode for time response. Excel 2013 and Minitab 18.1 software used for statistical calculations. Results analyzed by Minitab 18.1 software. The highest harmful frequency in Shiraz Gas Power Plant (SGPP) was 50 Hz with 115 dB. The sound pressure level (SPL) ranged from 45 dB to 120 dB in one-third octave band and weighting network C. The maximum sound pressure level was in Craft electricity generator with 105.3 dB and 67 Hz. Sound pressure level in surrounded environment was 120 dB. According to the results, in this industry the sound pressure level exceeded the Occupational Exposure Level of Iran (OEL). The value of sound pressure level were higher than the Standard of occupational health. SGPP consumes 47000 cubic meters of natural gas per hour to produce 100 MW (Mega Watt) of electricity. It is very high and it is not economical and cost effective. These numbers indicate that the power plant’s efficiency is low. It could be concluded that the noise pollution is an important issue in these industries. Moreover, SGPP produce noise with loss energy. Frequencies rotation at high sound pressure levels toward low frequencies were happened. 相似文献
56.
Finite dimensional representations of extended Weyl-Heisenberg algebra are studied both from mathematical and applied viewpoints. They are used to define unitary phase operator and the corresponding eigenstates (phase states). It is also shown that the unitary depolarizers can be constructed in a general setting in terms of phase operators. Generation of generalized Bell states using the phase operator is presented and their expressions in terms of the elements of mutually unbiased bases are given. 相似文献
57.
K. Mohammed Jasim 《Optics and Lasers in Engineering》2011,49(7):785-792
The present paper reports an experimental investigation based on X-ray diffraction (XRD), energy dispersive spectroscopy (EDS), and wavelength dispersive spectroscopy (WDS) analyses of phases formed after laser sealing of plasma sprayed coatings of 8.5 wt% yttria partially stabilized zirconia (YPSZ). X-ray diffraction and X-ray step-scanning analyses showed that the plasma sprayed and sealed coatings consisted mainly of t′ phase with a very small amount of monoclinic phase (m phase) in the plasma sprayed coatings. It was also found that the small amounts of m and cubic phases (c phase) present in the sealed coatings were dependent on laser processing specific energies (specific energy is equal to laser power/traverse speed x beam diameter). It was also found that rhombohedral (r) phase formed after laser sealing of coatings at higher specific energies. A direct relationship between c/a ratio of transformable tetragonal phase (t phase) produced by thermal treatment of sealed coatings and nontransformable tetragonal phase (t′ phase) and the amount of Yttria was obtained. A new equation was derived, which describes the relationship between Yttria concentration and the c/a ratio of tetragonal phases (t or t′). 相似文献
58.
K. Bahedi M. AddouM. El Jouad Z. SofianiH. EL Oauzzani B. Sahraoui 《Applied Surface Science》2011,257(18):8003-8005
Nanocrystalline ZnO:Al thin films were deposited by reactive chemical pulverization spray pyrolysis technique on heated glass substrates at 450 °C to study their crystalline structure, composition, strain, stress, roughness characteristics and nonlinear optical susceptibility as a function of Al concentration (0, 2, 3, 5 at.%). The films were characterized by X-ray diffractometer (XRD), EDAX 9100 analyser, atomic force microscopy (AFM) and third harmonic generation (THG). The Al (3 at.%) doped ZnO thin films exhibited the lower strain/stress than undoped films. The nonlinear properties of the ZnO:Al thin films have been found to be influenced by the films strain/stress. 相似文献
59.
A. El Allati M. El Baz Y. Hassouni A. Kassou Ou Ali F. Saif 《Journal of Russian Laser Research》2011,32(2):177-187
We suggest a model where the influence of an environment on the atom interference is associated with a random phase. The model consists of sending a two-level state atom through two cavities, both containing a standing wave field in the Bragg regime and Raman–Nath regime, respectively. In view of this model, we can visualize the loss of interference fringes if the randomness of the phase increases, and the restoration of the pattern when it decreases, as which-path information. Then, the controllable random noise acts as a decoherence that would destroy the quantum features. 相似文献
60.