| Abstract: | Alkylation of phenol with methanol has been carried out over Sn-La and Sn-Sm mixed oxides of varying compositions at 623 K in a vapour phase flow reactor. It is found that the product selectivity is greatly influenced by the acid-base properties of the catalysts. Ortho-cresol formation is favoured over catalysts with weak acid sites whereas formation of 2,6-xylenol occurs in the presence of stronger acid sites. The cyclohexanol decomposition reaction and titrimetric method using Hammett indicators have been employed to elucidate the acid-base properties of the catalysts. |
| Description: | Indian Journal of Chemistry Vol. 38A, December 1999, pp. 1253-1255 |
| URI: | http://dyuthi.cusat.ac.in/purl/2147 |
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| Dyuthi-P0005.pdf | (224.0Kb) |
| Abstract: | Almost self-centered graphs were recently introduced as the graphs with exactly two non-central vertices. In this paper we characterize almost selfcentered graphs among median graphs and among chordal graphs. In the first case P4 and the graphs obtained from hypercubes by attaching to them a single leaf are the only such graphs. Among chordal graph the variety of almost self-centered graph is much richer, despite the fact that their diameter is at most 3. We also discuss almost self-centered graphs among partial cubes and among k-chordal graphs, classes of graphs that generalize median and chordal graphs, respectively. Characterizations of almost self-centered graphs among these two classes seem elusive |
| Description: | TAIWANESE JOURNAL OF MATHEMATICS Vol. 16, No. 5, pp. 1911-1922, October 2012 |
| URI: | http://dyuthi.cusat.ac.in/purl/4213 |
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| Almost Self-Centered Median And Chordal Graphs.pdf | (225.6Kb) |
| Abstract: | The brain stems (13S) of streptozotocin (STZ)-diabetic rats were studied lo see the changes in neurotransmitter content and their receptor regulation. The norepinephrine (NE) content determined in the diabetic brain stems did ^ control. an E showed la while PI turnover hri content increased significantly compared N^r eNveFa o the recep significant increase. The alpha2 adrenergic receptor IneP utisoulinntreat d ratsetheNE contentt dec^ sled was significantly reduced during diabetes. in versedcto reanorm sed ulcrea e tK reatment the state. while EPI content remained increased as in die diabetic B,, for a]pha2 adrenergic receptors slw^nificantly while Unlabelled clonidine inhibited [31-I]NE binding in BS of control, diabetic and insulin treated ulations bindi diabetic rats showed that alpha2 adrenergicre^ punks cojnidiabetic animal the ligand bound sites with Hill slopes significantly away from unity. weaker to the low affinity site than in controls. Insulin treatment reversed[ this allumbmn to control levels. The displacement analysis using (-)-epinephrine age in control and diabetic animals revealed two populations of receptor affinidtyo=tat ss. In control animals, when GTP analogue added with epinephrine, the curve nagnlde caofnfitnroit yS model; but in the diabetic BS this effect `not aobserved. In bintact oth the diabetic data thus showlthat the effects of monovalent cations on affinity alphaz adrenergic receptors have a reduced affinity v due in stem ialtered Itscppeomson(5- regulation. The serotonin (5-HT) coat hydroxy) tryptophan (5-HTP) showed an increase and its breakdown metabolite (5-hydroxy) indoleacetic acid (5-I{IAA) showed a significant decrease. This showed that in serotonergic which l nerves there is a disturbance in both synthetic and breankduomwnbers pretma'med ana increased 5-HT. The high affinity serotonin receptor um ese serotonerg decrease in the receptor affinity. The insulin ^treatmentsturtiy showsha decreased serotonergic receptor kinetic parameters to control level. receptor function. These changes in adrenergic and serotonergic receptor function were suggested to be important in insulin function during STZ diabetes. |
| URI: | http://dyuthi.cusat.ac.in/purl/583 |
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| Pius and C S P (1999)april 2.PDF | (8.614Mb) |
| Abstract: | Moderate pyridoxine deficiency in adult male Sprague-Dawley rats results in significant hypertension, associated with a general sympathetic stimulation , including an increase in the turnover of norepinephrine in the heart. Treatment of these rats with pyridoxine reversed blood pressure to normal within 24 h. Treatment of pyridoxine-deficient rats with clonidine or x-methyl dihydroxyphenylalanine (x-methyl DOPA) also reduced the blood pressure of these animals to normal . There was also a significant increase in the Bma, of high and low affinity [3H]p-amino-clonidine binding to crude synaptosomal membrane preparations of the brain stem of deficient rats indicating chronic underexposure of)(, adrenoreceptors to endogenous norepinephrin. |
| URI: | http://dyuthi.cusat.ac.in/purl/592 |
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| M Viswanathan and others(1989)nov.27PDF.PDF | (3.599Mb) |
| Abstract: | Muscarinic M1 and M3 receptor changes in the brain stem during pancreatic regeneration were investigated. Brain stem acetylcholine esterase activity decreased at the time of regeneration . Sympathetic activity also decreased as indicated by the norepinephrine (NE) and epinephrine (EPI) content of adrenals and also in the plasma. Muscarinic Ml and M3 receptors showed reciprocal changes in the brain stem during regeneration. Muscairnic M1 receptor number decreased at time of regeneration without any change in the affinity. High affinity M3 receptors showed an increase in the number. The affinity did not show any change . The number of low affinity receptors decreased with decreased Kd at 72 hours after partial pancreatectomy. The Kd reversed to control value with a reversal of the number of receptors to near control value . Gene expression studies also showed a similar change in the mRNA level of Ml and M3 receptors . These alterations in the muscarinic receptors regulate sympathetic activity and maintain glucose level during pancreatic regeneration. Central muscarinic M1 and M3 receptor subtypes functional balance is suggested to regulate sympathetic and parasympathetic activity, which in turn control the islet cell proliferation and glucose homeostasis. |
| URI: | http://dyuthi.cusat.ac.in/purl/574 |
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| T R Renuka and others(2004)march.PDF | (8.838Mb) |
| Abstract: | This is a sequel to our earlier work on the modulated logistic map. Here, we first show that the map comes under the universality class of Feigenbaum. We then give evidence for the fact that our model can generate strange attractors in the unit square for an uncountable number of parameter values in the range μ∞<μ<1. Numerical plots of the attractor for several values of μ are given and the self-similar structure is explicity shown in one case. The fractal and information dimensions of the attractors for many values of μ are shown to be greater than one and the variation in their structure is analysed using the two Lyapunov exponents of the system. Our results suggest that the map can be considered as an analogue of the logistic map in two dimensions and may be useful in describing certain higher dimensional chaotic phenomena. |
| URI: | http://dyuthi.cusat.ac.in/purl/2567 |
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| Dyuthi-P0126.pdf | (484.3Kb) |
| Abstract: | A dual-port dual-polarized compact microstrip antenna for avoiding cross coupling between the two frequency bands is proposed and analyzed. This antenna offers channel isolation better than 25 dB, and is more compact compared to a conventional rectangular patch. Analytical equations for calculating the resonant frequencies at both ports are also presented. The theoretical calculations are verified using experimental results |
| URI: | http://dyuthi.cusat.ac.in/purl/1393 |
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| Analysis and de ... act microstrip antenna.PDF | (1.268Mb) |
| Abstract: | Most adaptive linearization circuits for the nonlinear amplifier have a feedback loop that returns the output signal oj'tne eunplifier to the lineurizer. The loop delay of the linearizer most be controlled precisely so that the convergence of the linearizer should be assured lot this Letter a delay control circuit is presented. It is a delay lock loop (ULL) with it modified early-lute gate and can he easily applied to a DSP implementation. The proposed DLL circuit is applied to an adaptive linearizer with the use of a polynomial predistorter, and the simulalion for a 16-QAM signal is performed. The simulation results show that the proposed DLL eliminates the delay between the reference input signal and the delayed feedback signal of the linearizing circuit perfectly, so that the predistorter polynomial coefficients converge into the optimum value and a high degree of linearization is achieved |
| URI: | http://dyuthi.cusat.ac.in/purl/1386 |
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| Analysis and de ... h loop delay estimator.PDF | (549.4Kb) |
| Abstract: | A novel optical add-drop multiplexer (OADM) based on the Mach-Zelauler interferometer (MZI) and the fiber Bragg grating (FBG) is proposed for the first tittle to the authors ' knowledge. In the structure, the Mach-Zehnder interferometer acts as an optical switch. The principle of the OADM is analyzed in this paper. The OADM can add/drop one of the multi-input channels or pass the channel directly by adjusting the difference of the two arms of the interferometer. The channel isolation is more than 20 dB |
| URI: | http://dyuthi.cusat.ac.in/purl/1427 |
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| Analysis and te ... ehnder interferometer.PDF | (255.6Kb) |
| Abstract: | A new compact microstrip antenna element is analyzed. The analysis can accurately predict the resonant frequency, input impedance, and radiation patterns. The predicted results are compared with experimental results and excellent agreement is observed . These antenna elements are more suitable in applications where limited antenna real estate is available |
| URI: | http://dyuthi.cusat.ac.in/jspui/handle/dyuthi/1568 |
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| Analysis of a New Compact Microstrip Antenna.PDF | (3.188Mb) |
| Abstract: | A new compact micro strip antenna element is analyzed. The analysis can accurately predict the resonant frequency, input impedance, and radiation patterns. The predicted results are compared with experimental results and excellent agreement is observed . These antenna elements are more suitable in applications where limited antenna real estate is available |
| URI: | http://dyuthi.cusat.ac.in/purl/1362 |
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| Analysis of a New Compact Microstrip Antenna.PDF | (3.188Mb) |
| Abstract: | The closed form expression for the radiated power of a half-wave microstrip patch is modified to calculate the impedance bandwidth of a printed dipole. Analyses of cavity backed flared and end-loaded printed dipoles are presented |
| URI: | http://dyuthi.cusat.ac.in/jspui/handle/dyuthi/1578 |
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| Analysis of cavity backed printed dipoles.PDF | (989.1Kb) |
| Abstract: | The operation of a previously proposed terahertz (THZ) detector is formulated in detail. The detector is based on the hot-electron effect of the 2D electron gas (2DEG) in the quantum well (QW) of a GaAs/AIGaAs heterostructure. The interaction between the THz radiation and the 2DEG, the current enhancement due to hot -electron effect, and the noise performance of the detector are analyzed |
| URI: | http://dyuthi.cusat.ac.in/purl/1399 |
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| Analysis of ter ... quantum well detector.PDF | (597.2Kb) |
| Abstract: | Urolithiasis is identified to be a major urological disorder affecting people all over the world irrespective of their age, sex and race. Urinary stone samples resected from the urinary bladders of two patients belonging to tropical region, Kollam District of Kerala State, India are investigated by using XRD,SEM, EDAX, TGA, DSC and FTIR to understand its chemical structure. Uric acid shows exothermic peak around 432°C is due to the decomposition with the evolution of CO and cracking of the remaining products. Results of analytical studies reveal that samples under investigation consist mainly in uric acid and hydrated uric acid. Hydrogen bonding exists in hydrated uric acid samples |
| Description: | Journal of Optoelectronics and Biomedical Materials Vol. 2, Issue 2, June 2010, p. 85 - 90 |
| URI: | http://dyuthi.cusat.ac.in/purl/4552 |
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| Analytical Char ... ies Of Urinary Calculi.pdf | (459.3Kb) |
| Abstract: | Design equations are presented for calculating the resonance frequencies for a compact dual frequency arrow-shaped microstrip antenna. This provides a fast and simple way to predict the resonant frequencies of the antenna. The antenna is also analyzed using the IE3D simulation package. The theoretical predictions are found to be very close to the IE3D results and thus establish the validity of the design formulae |
| URI: | http://dyuthi.cusat.ac.in/purl/1381 |
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| Analytical Equa ... ncy Microstrip Antenna.PDF | (2.229Mb) |
| Abstract: | An attempt is made to determine the relative power distribution in a step-index parabolic cylindrical waveguide (PCW) with high deformation across the direction of propagation. The guide is assumed to be made of silica. The scalar field approximation is employed for the analysis under which a vanishing refractive-index (RI) difference in the waveguide materials is considered. Further, no approximation for folds- is used in the analytical treatment. Due to the geometry of such waceguides, PCWs lose the well-defined modal discreteness, and a kind of mode bunching is observed instead, which becomes much more prominent in PCWs with high bends. However, with the increase in cross-sectional size, the mode-bunching tendency is slightly reduced. The general expressions for power in the guiding and nonguiding sections are obtained, and the fractional power patterns in all of the sections are presented for PCWs of various cross-sectional dimensions. It is observed that the confinement of power in the core section is increased for PCWs of larger cross-sectional size. Moreover, a fairly uniform distribution of power is seen over the modes having intermediate values of propagation constants |
| URI: | http://dyuthi.cusat.ac.in/purl/1394 |
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| An analytical s ... ylindrical deformation.PDF | (1.030Mb) |
| Abstract: | The present study is an attempt to highlight the problem of typographical errors in OPACS. The errors made while typing catalogue entries as well as importing bibliographical records from other libraries exist unnoticed by librarians resulting the non-retrieval of available records and affecting the quality of OPACs. This paper follows previous research on the topic mainly by Jeffrey Beall and Terry Ballard. The word “management” was chosen from the list of likely to be misspelled words identified by previous research. It was found that the word is wrongly entered in several forms in local, national and international OPACs justifying the observations of Ballard that typos occur in almost everywhere. Though there are lots of corrective measures proposed and are in use, the study asserts the fact that human effort is needed to get rid of the problem. The paper is also an invitation to the library professionals and system designers to construct a strategy to solve the issue |
| Description: | 9th International CALIBER - 2013, INFLIBNET Centre, Gandhinagar, Gujarat, March 21-23, 2013 |
| URI: | http://dyuthi.cusat.ac.in/purl/4457 |
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| Analytical Stud ... nd Corrective Measures.pdf | (115.5Kb) |
| Abstract: | The present study is an attempt to highlight the problem of typographical errors in OPACS. The errors made while typing catalogue entries as well as importing bibliographical records from other libraries exist unnoticed by librarians resulting the non-retrieval of available records and affecting the quality of OPACs. This paper follows previous research on the topic mainly by Jeffrey Beall and Terry Ballard. The word “management” was chosen from the list of likely to be misspelled words identified by previous research. It was found that the word is wrongly entered in several forms in local, national and international OPACs justifying the observations of Ballard that typos occur in almost everywhere. Though there are lots of corrective measures proposed and are in use, the study asserts the fact that human effort is needed to get rid of the problem. The paper is also an invitation to the library professionals and system designers to construct a strategy to solve the issue |
| Description: | 9th International CALIBER - 2013, INFLIBNET Centre, Gandhinagar, Gujarat, March 21-23, 2013 |
| URI: | http://dyuthi.cusat.ac.in/purl/4156 |
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| Analytical Stud ... nd Corrective Measures.pdf | (115.5Kb) |
| Abstract: | This paper discusses the complexities involved in managing and monitoring the delivery of IT services in a multiparty outsourcing environment. The complexities identified are grouped into four categories and are tabulated. A discussion on an attempt to model a multiparty outsourcing scenario using UML is also presented and explained using an illustration. Such a model when supplemented by a performance evaluation tool can enable an organization to manage the provision of IT services in a multiparty outsourcing environment more effectively |
| Description: | CSREA EEE |
| URI: | http://dyuthi.cusat.ac.in/purl/3893 |
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| Analyzing and M ... tsourcing Environment..pdf | (318.9Kb) |
| Abstract: | The double sulfate family (ABSO4), where A and B are alkali metal cations, is the object of great interest owing to the complexity and richness of its sequence of phase transition induced by temperature variation. A new sulfate salt characterized by the presence of water molecule in the unit cell with the chemical formula, Li2Na3(SO4)2⋅6H2O (LSSW), was obtained. The ultrasonic velocity measurement was done with pulse echo overlap technique [PEO]. All the six second order elastic stiffness constants, C11 = C22, C33, C44 = C55, C12, C14 and C13 = C23 are reported for the first time. The anisotropy in the elastic properties of the crystal are well explained by the pictorial representation of the polar plots of phase velocity, slowness, Young’s modulus and linear compressibility in a–b and a–c planes. |
| URI: | http://dyuthi.cusat.ac.in/xmlui/purl/1977 |
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| Anisotropy in elastic properties of lithium....pdf | (467.9Kb) |
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