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121.
We present a detailed analysis of the nonperturbativeβ function along the Wilson axis for theSU(3) pure gauge theory using the Monte Carlo renormalization group method. The scaling behavior of the string tension, the
deconfinement transition temperature, and the O++ glueball mass obtained from published data is compared. The results show that there is no asymptotic scaling forK
F=(6/g
2)<6.1. We also estimate the renormalized action generated by the √3 block transformation for use in future calculations. 相似文献
122.
In this paper, a theoretical analysis is carried out to estimate the sensitivity and the signal-to-noise ratio (SNR) of a fiber optic surface plasmon resonance (SPR) sensor when fibers with different dopants and different doping concentrations are used. The dopants considered are germanium oxide (GeO2), boron oxide (B2O3), and phosphorus pentoxide (P2O5) in a pure silica fiber. The variation of the dispersion relation with different dopants and doping concentrations are taken into account for the analysis. It is shown that the doping of B2O3 increases the sensitivity of the sensor while the effect of dopant on SNR is negligible. The analysis is extended to fiber optic SPR sensor with bimetallic layers. 相似文献
123.
MRI characterization of 9L-glioma in rat brain at 4.7 Tesla 总被引:3,自引:0,他引:3
S S Rajan L Rosa J Francisco A Muraki M Carvlin E Tuturea 《Magnetic resonance imaging》1990,8(2):185-190
In vivo estimation of intracranial tumor progression is important in tumor treatment response studies in animal models. High resolution MR images at 4.7 T of 9L-gliomas stereotactically implanted in Fisher-344 rat brains were obtained. Due to elongation of T1 at higher fields, tissue contrast is diminished in T1-weighted images. However, normal anatomy and vasogenic edema are clearly discerned in T2-weighted images (echo times of greater than 50 ms and recycle times of greater than 2 sec). Tumor tissue is not always clearly delineated. Images obtained after administration of contrast agents (Gadolinium DTPA), with short TR (0.6 sec) selectively enhanced the tumorous tissue, with little effect upon normal tissue and edema. Good correlation of enhanced tumor lesions has been observed with histological examination of formalin fixed brains. Relaxation times (T1 and T2) of tumor and normal tissues were measured using stimulated-echo and multi-echo sequences, respectively. Serial images corresponding to tumor growth were recorded, from which tumor volume progression was monitored. 相似文献
124.
Adsorption and expression of penicillin G acylase immobilized onto methacrylate polymers generated with varying pore generating solvent volume 总被引:1,自引:0,他引:1
A. Kotha L. Selvaraj C. R. Rajan S. Ponrathnam K. K. Kumar G. R. Ambekar J. G. Shewale 《Applied biochemistry and biotechnology》1991,30(3):297-302
Adsorption and expression of penicillin G acylase was studied on macroporous methacrylate polymer beads of differing pore volume, generated with kerosene. The absorption and expression of the penicillin G acylase was dependent on pore volume. Maximum expression of 57% of adsorbed enzyme was obtained on beads synthesized with 40 mL of kerosene, indicating minimum pore-diffusion limitations. 相似文献
125.
Correlations to predict droplet size in ultrasonic atomisation. 总被引:2,自引:0,他引:2
In conventional two fluid nozzles, the high velocity air imparts its energy to the liquid and disrupts the liquid sheet into droplets. If the energy for liquid sheet fragmentation can be supplied by the use of ultrasonic energy, finer droplets with high sphericity and uniform size distribution can be achieved. The other advantage of ultrasound induced atomisation process is the lower momentum associated with ejected droplets compared to the momentum carried by the droplets formed using conventional nozzles. This has advantage in coating and granulation processes. An ultrasonic probe sonicator was designed with a facility for liquid feed arrangement and was used to atomise the liquid into droplets. An ingenious method of droplet measurement was attempted by capturing the droplets on a filter paper (size variation with regard to wicking was uniform in all cases) and these are subjected to image analysis to obtain the droplet sizes. This procedure was evaluated by high-speed photography of droplets ejected at one particular experimental condition and these were image analysed. The correlations proposed in the literature to predict droplet sizes using ultrasound do not take into account all the relevant parameters. In this work, a truly universal correlation is proposed which accounts for the effects of physico-chemical properties of the liquid (flow rate, viscosity, density and surface tension), and ultrasonic properties like amplitude, frequency and the area of vibrating surface. The significant contribution of this work is to define dimensionless numbers incorporating ultrasonic parameters, taking cue from the conventional numbers that define the significance of different forces involved in droplet formation. The universal correlations proposed are robust and can be used for designing ultrasonic atomisers for different applications. Among the correlations proposed here, those ones that are based on the dimensionless numbers and Davies approach predict droplet sizes within acceptable limits of deviation. Also, an empirical correlation from experimental data has been proposed in this work. 相似文献
126.
Venkatraman Senthil Kumar Choudhary Rajan Genasan Krishnamurithy Murali Malliga Raman Raghavendran Hanumantha Rao Balaji Kamarul Tunku Suresh Anushree Abraham Jayanthi Venkateswaran Seshasailam Livingston Abel Swamiappan Sasikumar 《Journal of Sol-Gel Science and Technology》2021,100(3):506-516
Journal of Sol-Gel Science and Technology - Biocompatibility and bacterial infections are the primary concerns associated with the current bone graft substitutes. The application of... 相似文献
127.
S. Janarthanan R. Sugaraj Samuel Y. C. Rajan P. R. Umarani S. Pandi 《Journal of Thermal Analysis and Calorimetry》2012,109(1):69-72
The growth of semicarbazone of p-hydroxy benzaldehyde (SPHB) single crystal by slow evaporation solution growth technique is reported in this article. The grown crystal was subjected to powder XRD study to identify the crystalline nature. Single crystal XRD study was done to measure unit cell parameters and to confirm the crystal structure. In the presence of various functional groups of SPHB was identified by FTIR spectrum. Its optical behavior was examined by UV?CVis?CNIR spectrum and the crystal was found to have transparency in the region between 245 and 1100?nm. Thermal properties of the crystal were investigated using thermogravimetric and differential thermal analysis (TG-DTA), which indicated that the melting of the material occurred before decomposition. The nonlinear optical (NLO) property was tested by Kurtz?CPerry powder technique for second harmonic generations. 相似文献
128.
129.
M. A. Sutton F. Matta D. Rizos R. Ghorbani S. Rajan D. H. Mollenhauer H. W. Schreier A. O. Lasprilla 《Experimental Mechanics》2017,57(1):1-30
Since presentation of the 2013 Murray Lecture focusing on developments in digital image correlation (DIC), the methods have continued to expand internationally and their use has begun to grow in fields where there was less activity in the past. First, a brief history of digital image correlation methods is presented from the perspective of the first author, followed by a discussion of recent trends associated with the use of digital image correlation methods in academics, governmental laboratories and industrial settings. In the remainder of the article, new results are provided in three areas where DIC methods have seen rapid growth; application of StereoDIC or three-dimensional DIC (3D-DIC) to the study of wall structures in civil engineering; the use of Volumetric DIC or Digital Volume Correlation (DVC) to quantify the internal response of a specially-designed composite material and in the area of model validation for another application in civil engineering; transfer length measurements in pre-stressed concrete beams. 相似文献
130.
Scott R. Broderick Changwon Suh J Provine Christopher S. Roper Roya Maboudian Roger T. Howe Krishna Rajan 《Surface and interface analysis : SIA》2012,44(3):365-371
We have demonstrated an informatics methodology for finding correlations between the full profile Fourier transform infrared spectra of polycrystalline 3C‐silicon carbide (poly‐SiC) films and their growth conditions, thereby developing high‐throughput structure‐process relationships. Because SiC films are a structural element in photonic sensors, this paper focuses on the interpretation of their optical response, the multivariate tracking of critical processing pathways, and the identification of controlling processing mechanisms. Using principal component analysis, we have developed a data analysis tool to aid in the assessment of the relative contributions of experimental parameters in low‐pressure chemical vapor deposition processes to optical responses on the basis of the size of eigenvalues of the spectral data set. The applied methodology for identifying spectral relationships of stoichiometry, dopant chemistry, and microstructure of poly‐SiC provides more effective guidelines to manipulate optical responses by controlling multiple experimental parameters. Copyright © 2011 John Wiley & Sons, Ltd. 相似文献