Self Consistent Simulation of C-V Characterization and Ballistic Performance of Double Gate SOI Flexible-FET Incorporating QM Effects

Capacitance-Voltage (C-V) & Ballistic Current- Voltage (I-V) characteristics of Double Gate (DG) Silicon-on- Insulator (SOI) Flexible FETs having sub 35nm dimensions are obtained by self-consistent method using coupled Schrodinger- Poisson solver taking into account the quantum mechanical effects. Although, ATLAS simulations to determine current and other short channel effects in this device have been demonstrated in recent literature, C-V & Ballistic I-V characterizations by using self-consistent method are yet to be reported. C-V characteristic of this device is investigated here with the variation of bottom gate voltage. The depletion to accumulation transition point (i.e. Threshold voltage) of the C-V curve should shift in the positive direction when the bottom gate is negatively biased and our simulation results validate this phenomenon. Ballistic performance of this device has also been studied with the variation of top gate voltage.Comment: 4 pages, ICEDSA 2012 conferenc

A Physically Based Analytical Modeling of Threshold Voltage Control for Fully-Depleted SOI Double Gate NMOS-PMOS Flexible-FET

In this work, we propose an explicit analytical equation to show the variation of top gate threshold voltage with respect to the JFET bottom gate voltage for a Flexible Threshold Voltage Field Effect Transistor (Flexible-FET) by solving 2-D Poisson's equation with appropriate boundary conditions, incorporating Young's parabolic approximation. The proposed model illustrates excellent match with the experimental results for both n-channel and p-channel 180nm Flexible-FETs. Threshold voltage variation with several important device parameters (oxide and silicon channel thickness, doping concentration) is observed which yields qualitative matching with results obtained from SILVACO simulations.Comment: 4 pages, EIT 2012-IUPUI conferenc

Statistical modelling of nonpoint source pollution from a ropical urban residential area

Quantification of the pollutants generated due to rainfall-runoff process is tedious and expensive. On the other hand, the characteristics of runoff quality also depend on the landuses and rainfall patterns. Such difficulties can be simplified by the development of reliable and easy to use nonpoint source (NPS) regression models. Information on the statistical models for the estimation of NPS or diffuse pollution loading in many tropical countries, including Malaysia, is not available yet. Therefore, local data was used to develop multivariate statistical models to estimate various pollutants from the NPS or diffuse sources of a residential area. The multivariate regression models were developed for total dissolved solids (TDS), total suspended solids (TSS), zinc (Zn) and copper (Cu), which could be used to estimate pollution loading from the urban residential areas having activities and drainage system similar to the study area. Fifty six storm events of various durations and intensities were monitored for the study. It was observed that the rainfall data followed log-normal distribution at 95% confidence level. About 5% of the events had interevent dry period of less than 19.5 hours and 95% of the events occurred less than a gap of 169.8 hours. Forty six rain events were used to develop the regression models. Calibration and validation were done using another five rain events for each exercise. Models for other parameters exhibited low coefficients of determinations (less than 0.50) and, therefore, considered not useful for the estimation of pollution load form nonpoint sources of a developed urban residential area

PREPARATION AND CHARACTERIZATION OF LOW MOLECULAR WEIGHT CHITOSAN WITH DIFFERENT DEGREES OF DEACETYLATION BY THE ACID HYDROLYSIS METHOD

Objective: The objective of this research is to prepare Low Molecular Weight Chitosan (LMWC) by the acid hydrolysis method, using dilute hydrochloric acid (2M). LMWC has superior properties compared to the High Molecular Weight Chitosan (HMWC), especially in terms of water solubility, antibacterial and antifungal properties. These could open new potential applications for LMWC in sectors such as the cosmetics, food, and pharmaceutical industries. Methods: In this work, the acid hydrolysis method was used to produce LMWC with different molecular weights starting from 500 kDa and 93% degree of deacetylations (DDA). The molecular weights of the produced grades were determined by applying Mark-Houwink equation while the %DDA was determined and verified by the use of the 1st derivative UV method and 1HNMR method, respectively. The depolymerization reactions were carried out with different time intervals to produce totally deacetylated LMWC of 30 kDa, 15 kDa, and 7.5 kDa. The LMWC was characterized by FTIR, XRD, and DSC to evaluate the functionality, microstructure and thermal properties. Results: The FTIR spectra revealed that there is no significant difference in the main skeletal structure of the LMWC and HMWC. On the other hand, the XRD and DSC results showed that the LMWC of different molecular weights and degrees of deacetylation are of semi-crystalline structure, similar to the HMWC. Conclusion: The obtained results showed that the used acid hydrolysis procedure can produce LMWC grades of desired specifications, yields, and quality which are suitable for use in different applications

Assessment of Maximum Bite Force in Oral Submucous Fibrosis Patients: A Preliminary Study

Objective: To determine the maximum bite force (MBF) in oral submucous fibrosis (OSMF) patients and to compare them with that of healthy subjects. Material and Methods: Twenty patients who were clinically confirmed, as OSMF and 20 healthy controls matched for age, gender, and number of intact functional teeth were included in this study. For each subject, age, gender, weight, height and body mass index (BMI) were recorded. The MBF registration was carried out by the two evaluators, who were previously calibrated. Bite force was measured in the first molar region using a force transducer occlusal force meter for each subject seated at the upright position, with Frankfort's plane nearly parallel to the floor, and no head support. The Student’s independent t-test was used to determine the statistical significance in relation to mean height, weight, BMI and the presence of number of intact teeth and MBF between the healthy subjects and OSMF individuals. A comparison of grades of OSMF with all variables was carried out by one-way ANOVA test. Results: No significant difference was found in mean age, mean height, weight, BMI and the presence of the number of intact teeth between healthy individuals and OSMF patients. The mean MBF in healthy subjects was 628.23 ± 24.39 N and 635.47 ± 31.22 N in OSMF patients. Even though the healthy subjects reported a higher MBF than OSMF patients did, the difference was statistically non-significant. With regards to sides, no significant difference was observed in mean MBF in healthy subjects and OSMF patients on the right (p=0.7818) and left side (p=0.6154). Conclusion: The healthy subjects reported higher MBF values than OSMF patients did and the difference was statistically non-significant

Non-factorizable long distance contributions in color suppressed decays of B mesons

$\bar B \to D\pi$, $D^*\pi$, $J/\psi\bar K$ and $J/\psi\pi$ decays are studied. Their amplitude is given by a sum of factorized and non-factorizable ones. The latter which is estimated by using a hard pion approximation is rather small in color favored $\bar B \to D\pi$ and $D^*\pi$ decays but still can efficiently interfere with the main amplitude given by the factorization. In the color suppressed $\bar B \to J/\psi\bar K$ and $J/\psi\pi$ decays, the non-factorizable contribution is very important. The sum of the factorized and non-factorizable amplitudes can reproduce well the existing experimental data on the branching ratios for the color favored $\bar B \to D\pi$ and $D^*\pi$ and the color suppressed $\bar B \to J/\psi \bar K$ and $J/\psi\pi$ decays by taking reasonable values of unknown parameters involved.Comment: 19 pages, Revte

catena-Poly[[[tetra­kis­(4-methyl­pyridine-κN)copper(II)]-μ-sulfato-κ2 O:O′] 4.393-hydrate]

The structure of the title compound, {[Cu(SO4)(C6H7N)4]·4.393H2O}n, consists of Cu2+ ions surrounded in a square-planar fashion by 4-methyl­pyridine ligands, forming two crystallographically independent Cu{H3C(C5H4N)}4 units that are both located on crystallographic inversion centers. The Cu(4-methyl­pyridine)4 units are, in turn, connected with each other via bridging sulfate anions, leading to the formation of infinite [Cu{H3C(C5H4N)}4SO4]n zigzag chains along [001]. The completed coordination spheres of the Cu2+ ions are slightly distorted octa­hedral. The axial Cu—O bonds are elongated [average length = 2.42 (4) Å] compared to the equatorial Cu—N bonds [average length = 2.043 (2) Å]. The inter­stitial space between the chains is filled with uncoordinated water mol­ecules that consolidate the structure through O—H⋯O hydrogen bonding. One of the five crystallographically independent solvent water mol­ecules is partially occupied with an occupancy factor of 0.396 (4). Due to hydrogen bonding between symmetry-equivalent water mol­ecules across inversion centers, several of the water H atoms are disordered in 1:1 ratios over mutually exclusive positions. The crystal under investigation was found to be non-merohedrally twinned in a 0.789 (1):0.211 (1) ratio by a 180° rotation around the reciprocal b axis