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Morphometric analysis of the cervical spine of Indian population by using computerized tomography
Partha Sarathi Banerjee,Amit Roychoudhury,Santanu Kumar Karmakar
Journal of Medical and Allied Sciences , 2012,
Abstract: The purpose of the present study was to measure the surgically important morphological parameters of cervical spine region of a representative sample of Indian population from the images obtained through computerized tomography (CT). Another purpose has been to compare the computed statistical mean, standard deviation and range of variation of these data with those of other Asian population and also European/American populations. With that aim, ninety five (95) CT scan data of Indian people (73 for male patients and 22 for female patients) pertaining to undeformed normal cervical spine has been collected from an Indian hospital. From these, 15 important morphological parameters have been measured. These values have been tabulated and their mean, standard deviation and range of variation have been computed. It has been found that pedicle dimensions of Indian people are smaller at almost all vertebra levels as compared to Caucasian people. Pedicle axis length for Indian people are found to be smaller at C3, C4 and C5 levels than those for other Asian people including Chinese people, but it is bigger at C6 and C7 levels. Indian people have longer measurements of pedicle length + lateral mass on an average than their other Asian counterparts at C5, C6 and C7 levels, but shorter measurements at C3 and C4 levels. The results of the present work may help in better understanding of morphological parameters of cervical spine region of Indian population. It may be further useful in designing spinal implants which would be biomechanically compatible to the anatomy of Indian people.
A Numerical Characterization of the Gravito-Electrostatic Sheath Equilibrium Structure in Solar Plasma  [PDF]
Pralay Kumar Karmakar, Chandra Bhushan Dwivedi
International Journal of Astronomy and Astrophysics (IJAA) , 2011, DOI: 10.4236/ijaa.2011.14027
Abstract: This article describes the equilibrium structure of the solar interior plasma (SIP) and solar wind plasma (SWP) in detail under the framework of the gravito-electrostatic sheath (GES) model. This model gives a precise definition of the solar surface boundary (SSB), surface origin mechanism of the subsonic SWP, and its supersonic acceleration. Equilibrium parameters like plasma potential, self-gravity, population density, flow, their gradients, and all the relevant inhomogeneity scale lengths are numerically calculated and analyzed as an initial value problem. Physical significance of the structure condition for the SSB is discussed. The plasma oscillation and Jeans time scales are also plotted and compared. In addition, different coupling parameters, and electric current profiles are also numerically studied. The current profiles exhibit an important behavior of directional reversibility, i.e., an electrodynamical transition from negative to positive value. It occurs beyond a few Jeans lengths away from the SSB. The virtual spherical surface lying at the current reversal point, where the net current becomes zero, has the property of a floating surface behavior of the real physical wall. Our investigation indicates that the SWP behaves as an ion current-carrying plasma system. The basic mechanism behind the GES formation and its distinctions from conventional plasma sheath are discussed. The electromagnetic properties of the Sun derived from our model with the most accurate available inputs are compared with those of others. These results are useful as an input element to study the properties of the linear and nonlinear dynamics of various solar plasma waves, oscillations and instabilities.
Equilibrium of the Extraction of V(IV) in the V(IV)-SO42-(H+, Na+)—Cyanex 302-Kerosene System  [PDF]
Ranjit Kumar Biswas, Aneek Krishna Karmakar
International Journal of Nonferrous Metallurgy (IJNM) , 2012, DOI: 10.4236/ijnm.2012.13004
Abstract: The title system has been investigated from the equilibrium point of view. Significant extraction occurs above pH 2. Equilibration time is 20 min. The extraction ratio (D) remains constant with increasing [V(IV)] of at least 0.50 g/L. It is inversely proportional to [H+]2, [H+] and [H+]0.3 in the lower pH (<2.25), medium pH (~2.90) and higher pH (~4.0) regions, respectively. Moreover, it is proportional to [Cyanex 302]2; and [SO42-]0 and [SO42-]-1 in the lower [SO42-] (<0.05 mol/L) and higher [SO42-] (>1 mol/L) regions, respectively. The apparent extraction equilibrium constant (Kex) in 0.02 mol/L SO42- medium and at 303 K is found to vary from 10-3.447 to 101.508 with increasing equilibrium pH from 2.25 to 4.00. Various sulphated, hydrolyzed, hydrated and mixed sulphated hydrolyzed species of V(IV) have been considered at different extraction conditions to propose the extraction equilibrium reactions to form always [VO(HA2)2] as the extractable species. The system is highly temperature dependent with ?H value of ~90 kJ/mol and ~25 kJ/mol in lower and higher temperature regions, respectively. The calculated loading capacity is low (4.05 g V(IV)/100 g Cyanex 302). Kerosene is a better diluent over CHCl3, Cyclo-C6H12 and CCl4; but much better solvents are C6H6, C6H5CH3, n-C7H16,C6H4(CH3)2, petroleum benzin, 1,2-C2H4Cl2, C6H5Cl. Mineral acids (1 mol/L) are able to strip off V(IV) from the organic phase in a single-stage. Using Cyanex 302, almost complete separations of V(IV) from Cu(II) at pH 1.0 and from Ni(II) at pH(eq) 4.5 are possible in a single-stage of extraction; whereas, its separation from Zn(II) at pH(eq) 2.5, Co(II) at pH(eq) 3.5, Fe(III) at pH(eq) 2.0 and Ti(IV) at pH(eq) 2.5 will require counter-current multi-stage extractions.
Liquid-Liquid Extraction of V(IV) from Sulphate Medium by Cyanex 301 Dissolved in Kerosene  [PDF]
Ranjit Kumar Biswas, Aneek Krishna Karmakar
International Journal of Nonferrous Metallurgy (IJNM) , 2013, DOI: 10.4236/ijnm.2013.21003
Abstract:

The equilibrium of extraction of V(IV) in the V(IV)- SO42- (H+, Na+)-Cyanex 301 (HA)-kerosene system has been studied. Significant extraction occurs above pH 1 within 10 min. CD (extraction ratio at constant pH(eq) and [HA](o,eq)) value is slightly decreased with increasing [V(IV)](ini). CD is found to be directly proportional to [H+]-n (n ≤ 2), [HA] 2 and (1+1.58 [SO

Karyological and Electrophoretic Distinction between Sexes of Trichosanthes bracteata  [PDF]
Kanika Karmakar, Rabindra Kumar Sinha, Sangram Sinha
American Journal of Plant Sciences (AJPS) , 2013, DOI: 10.4236/ajps.2013.43062
Abstract: Chromosome studies and soluble protein profiles, fractionated by reducing and non-reducing SDS-PAGE, were carried out in dioecious Trichosanthes bracteata. Somatic chromosome no. 2n = 22 was recorded in both sexes. The karyotype of male and female plant shows high homogeneity and the absence of any heteromorphic pair of chromosomes negates the possibility of XY mechanism. Soluble protein profiles from the tuberous roots of the male and female plants, fractionated by reducing SDS-PAGE, did not show any qualitative distinction. Whereas the protein profile in non-reducing SDS-PAGE reveals a clear distinction when compared on a single gel. The difference is marked by the presence of a disulphide linked tertiary or folded protein at 19 k D region detected in male sex. However, at the level of primary structure the qualitative expression is similar indicating a common ancestry.
Quantum transport through molecular wires
Santanu K. Maiti,S. N. Karmakar
Physics , 2008, DOI: 10.1142/S021797920904970X
Abstract: We explore electron transport properties in molecular wires made of heterocyclic molecules (pyrrole, furan and thiophene) by using the Green's function technique. Parametric calculations are given based on the tight-binding model to describe the electron transport in these wires. It is observed that the transport properties are significantly influenced by (a) the heteroatoms in the heterocyclic molecules and (b) the molecule-to-electrodes coupling strength. Conductance ($g$) shows sharp resonance peaks associated with the molecular energy levels in the limit of weak molecular coupling, while they get broadened in the strong molecular coupling limit. These resonances get shifted with the change of the heteroatoms in these heterocyclic molecules. All the essential features of the electron transfer through these molecular wires become much more clearly visible from the study of our current-voltage ($I$-$V$) characteristics, and they provide several key informations in the study of molecular transport.
Physio-Biochemical and Microsatellite Based Profiling of Lowland Rice (Oryza sativa L.) Landraces for Osmotic Stress Tolerance  [PDF]
Rajib Roychowdhury, Joydip Karmakar, Joydip Karmakar, Malay Kumar Adak, Narottam Dey
American Journal of Plant Sciences (AJPS) , 2013, DOI: 10.4236/ajps.2013.412A3007
Abstract:

Global climate changes accelerate a wide range of abiotic stresses leading to a series of physiological, biochemical and molecular changes that adversely affect the growth and productivity of rice (Oryza sativa L.). In this background, there is limited knowledge and profiling reports of lowland, less popular rice landraces in relation to their osmotic stress tolerance. Laboratory mediated physiological and biochemical screening for a selected set of 20 lowland rice landraces was done in induced drought and salinity stress conditions. Varietal genetic diversity and inter-relatedness were assessed by using osmotic stress tolerance linked forty-five rice microsatellite markers. For representing the allelic diversity of the studied microsatellite loci across the selected genotypes, a microsatellite panel was constructed and PIC values of all used microsatellite markers were calculated. The obtained database can be used for varietal identification, characterization and genetic information in relation to osmotic stress tolerance.

A Phenomenological Analysis of MEMS-Based Sensor for Toxic Gas Sensing in Coal Mine .
Santanu Maity,Avishek Kumar
International Journal of Engineering Sciences & Research Technology , 2013,
Abstract: In coal mine different types of toxic gases are present. There is an increasing demand on toxic gas sensor for coal mine where the power consumption is a big issue. In this paper a simple structure of micro heater and inter digited electrode has been fabricated and micro machined structure for low power consumption is demonstrated. MEMS microheaters are designed and fabricated for entire two inch (2") process and 3mm X 3mm die sizedmicroheaters obtained.
Extraction Kinetics of Ni(II) in the Ni2+- SO42--Ac-(Na+, H+)-Cyanex 272 (H2A2)-Kerosene-3% (v/v) Octan-1-ol System Using Single Drop Technique  [PDF]
Ranjit Kumar Biswas, Aneek Krishna Karmakar, Muhammad Saidur Rahman
International Journal of Nonferrous Metallurgy (IJNM) , 2013, DOI: 10.4236/ijnm.2013.22011
Abstract:

The kinetics of extraction of Ni(II) in the Ni2+-SO4 2_AC- (Na+, H+)-Cyanex 272 (H2A2)-kerosene-3% (v/v) octan-1-ol system using the single falling drop technique have been reported. The flux of Ni2+ transfer (F) at 303 K in presence of 3% (v/v) octan-1-ol (de-emulsifier) can be represented as:\"\".Depending on reaction parameters, the activation energy (Ea) and enthalpy change in activation (DH±) varies within 17 - 58 kJ/mol and 17 -

Categorization and Reorientation of Images Based on Low Level Features  [PDF]
Rajen Bhatt, Gaurav Sharma, Abhinav Dhall, Naresh Kumar, Santanu Chaudhury
Journal of Intelligent Learning Systems and Applications (JILSA) , 2011, DOI: 10.4236/jilsa.2011.31001
Abstract: A hierarchical system to perform automatic categorization and reorientation of images using content analysis is pre-sented. The proposed system first categorizes images to some a priori defined categories using rotation invariant features. At the second stage, it detects their correct orientation out of {0o, 90o, 180o, and 270o} using category specific model. The system has been specially designed for embedded devices applications using only low level color and edge features. Machine learning algorithms optimized to suit the embedded implementation like support vector machines (SVMs) and scalable boosting have been used to develop classifiers for categorization and orientation detection. Results are presented on a collection of about 7000 consumer images collected from open resources. The proposed system finds it applications to various digital media products and brings pattern recognition solutions to the consumer electronics domain.
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