In this paper, a combination of ferroelectric (FE) HfZrO
2
and dielectric (DE) SiO
2
is used to generate negative capacitance (NC) effects in Hetero Material (HM) tunnel FETs (TFETs). We have ...investigated the performance of some III-V alloys and Group IV semiconductors along with the FE-DE gate stack. The electric field at the tunnel junction adequately improved due to potential intensification in the presence of NC that leads to reduced threshold voltage (V
th
). Also, a suitable combination of low and high band gap III-V and IV semiconductors in the source and drain/channel regions improves ON current (I
ON
) and subthreshold swing (SS) significantly as compared to the conventional TFET device. Here we present a comparison of DC/RF/linearity analysis among a wide variety of NC-HM-TFETs, which is not reported previously to the best of our knowledge. We found that Ge/GaAs based device provides better I
ON
/I
OFF
= 1.95 × 10,
13
V
th
= 0.41, SS =12.2 mV/dec, g
m
= 47.7μS and f
t
= 4.89GHz after final device optimization, which concludes higher energy proficiency and superior performance in comparison to conventional TFET.
In this study, we have performed a comparative optical analysis for three different nanostructures such as nanowire, truncated nanocone, and inverted truncated nanocone for both Si and InP in the ...wavelength range from 300 to 1130 nm and 300–930 nm respectively, where the higher wavelength corresponds to the bandgap of Si and InP respectively. The simulations are performed in the Wave Optics Module of COMSOL Multiphysics. Height and diameter optimization of the proposed Si and InP nanostructures is performed. The results reveal that the truncated nanocone possesses superior anti-reflection properties as compared to inverted truncated nanocone and nanowire. We have also shown the absorptance spectrum for Si and InP-based nanostructures. Highest optical short circuit current density (Jsc) of 32.81 mA/cm2 is achieved with InP truncated nanocone structure with height of 400 nm, base diameter of 125 nm and pitch of 300 nm.
Though ductile to brittle transition (DBT) is a typical feature of body centered cubic materials, the present 12Cr-10Ni precipitation hardened martensitic stainless steel exhibited excellent low ...temperature impact toughness. This was, however, dependant on the aging temperature. 250°C aging led to higher toughness both at room temperature and at −196°C (77K). Specimens aged at 400 and 500°C, on the other hand, displayed significantly lower sub-zero impact properties. Though martensite packet size, and size distribution, were identical between the two ageing treatments; there was clear evidence of second phase coarsening: from very fine precipitates of less than ~ 10nm to relatively coarser second phase of ~ 5–25nm range. It is suggested that precipitate coarsening and associated loss of coherency are the limiting factors to the DBT performance of this important class of material.
A series of molecular spheroids (SP1-SP4) was synthesized using pseudolinear bisimidazole and bisbenzimidazole donors in combination with Pd(NO
)
acceptor via coordination-driven self-assembly. They ...were characterized by NMR and mass spectrometry, and the solid-state structures of SP1 and SP3 were confirmed by X-ray diffraction. Crystal packing revealed the presence of molecular channels with water molecules in the channels as proton source. All the systems showed proton conductivity across a wide range of temperature and relative humidity. Furthermore, the mode of proton conduction in these molecular spheroids was explored by performing a control experiment using 2,4-dinitrophenol molecule, which indicates that the proton conductivity in the present case increases with increasing surface area of these molecular spheroids.
Rotavirus genotypes, G1–G4 and G9 are associated with childhood diarrhoea throughout the world. In our previous study, we detected G1, G2, G4 and three G12 strains from Kolkata, India.
To study the ...prevalence of G- and P-genotypes of rotaviruses associated with dehydrating diarrhoea in children admitted to two leading hospitals in eastern India.
An active surveillance was conducted for elucidation of rotavirus infection in two leading hospitals in Kolkata, West Bengal and Berhampur (GM), Orissa, India, separated by 603
km from January 2003 to April 2005. The rotaviruses were detected by RNA electrophoresis in polyacrylamide gels. G- and P-typing of the positive samples were accomplished by amplifying VP7 and VP4 genes by RT-PCR and genotyped by seminested multiplex PCR methods. Sequencing, sequence analysis and phylogenetic analysis of VP7 genes of G12 strains were carried out to understand the variations between the strains isolated from different parts of the world.
The genotypic distribution varied remarkably from our earlier study period (1998–2001) with G1 (53.8%) being the most predominant strain followed by G2 (22.5%), G12 (17.1%), G9 (2.1%) and not a single G3 or G4 isolate was detected separately. 35.2% samples exhibited mixed P-types followed by P4 (31.7%), P8 (21.8%) and P6 (9.8%). The phylogenetic analysis of G12 strains revealed that the G12 strains detected from different parts of the world clustered into three different lineages. Though VP7 sequences of G12 strains isolated from Kolkata and Berhampur are conserved, their P-types were different.
During this study period we reported emergence of G12 strains as an important pathogen among children in eastern India, thus necessitating its inclusion in future polyvalent vaccine to control rotavirus diarrhoea.
Recently, the nodal domain counts of planar, integrable billiards with Dirichlet boundary conditions were shown to satisfy certain difference equations in Samajdar and Jain (2014). The exact ...solutions of these equations give the number of domains explicitly. For complete generality, we demonstrate this novel formulation for three additional separable systems and thus extend the statement to all integrable billiards.
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