Gravity-free hydraulic jumps and metal femtoliter cups

Hydraulic jumps created by gravity are seen everyday in the kitchen sink. We show that at small scales a circular hydraulic jump can be created in the absence of gravity by surface tension. The theory is motivated by our experimental finding of a height discontinuity in spreading submicron molten metal droplets created by pulsed-laser ablation. By careful control of initial conditions, this leads to solid femtoliter cups of gold, silver, copper, niobium, and tin.     

Molecular Cloning,Characterization, and Expression Analysis of Lignin Genes from Sugarcane Genotypes Varying in Lignin Content

Sugarcane (Saccharum spp.) is one of the highest biomass-producing plant and the best lignocellulosic feedstock for ethanol production. To achieve more efficient conversion of biomass to ethanol, a better understanding of the main factors affecting biomass recalcitrance is needed. Therefore, with this objective, here, we report a systematic study on lignin content, deposition, identification, and cloning of genes involved in lignin biosynthesis and their differential expression in five sugarcane clones, EC11003, EC11010, IK 76-91, IK 76-99, and Co 86032. Lignin content among the clones varied from 26.87 to 23.19 % with the highest in the clone EC11010 and the lowest in high sugar Co86032. Lignin deposition studied through phloroglucinol staining of the cell walls implied that the sclerenchyma cells of the energy canes (EC11010 and EC11003) have more lignin deposition followed by the Erianthus (IK 76-91 and IK 76-99) clones whereas Co86032 has the minimum amount of lignin deposition. We cloned partial coding regions of important genes of lignification COMT (650 bp), CCR (332 bp), and PAL (650 bp) from Erianthus, wild relative of sugarcane followed by the expression analysis through real-time PCR. Differential expression analysis showed high level of expression for the three genes in the energy cane EC11010.     

Dark matter results from 100 live days of XENON100 data

We present results from the direct search for dark matter with the XENON100 detector, installed underground at the Laboratori Nazionali del Gran Sasso of INFN, Italy. XENON100 is a two-phase time-projection chamber with a 62 kg liquid xenon target. Interaction vertex reconstruction in three dimensions with millimeter precision allows the selection of only the innermost 48 kg as the ultralow background fiducial target. In 100.9 live days of data, acquired between January and June 2010, no evidence for dark matter is found. Three candidate events were observed in the signal region with an expected background of (1.8 ± 0.6) events. This leads to the most stringent limit on dark matter interactions today, excluding spin-independent elastic weakly interacting massive particle (WIMP) nucleon scattering cross sections above 7.0 × 10(-45) cm(2) for a WIMP mass of 50 GeV/c(2) at 90% confidence level.     

Nanosized drug formulations under microfluidic continuous flow

We present a simple method involving a rotating tube processor to fabricate ultrafine crystalline drug nanoparticles under microfluidic continuous flow with precise control over particle size, with significantly enhanced dissolution of the drug.     

A search method for optimal control of a flow shop system of traditional machines

We consider a convex and nondifferentiable optimization problem for deterministic flow shop systems in which the arrival times of the jobs are known and jobs are processed in the order they arrive. The decision variables are the service times that are to be set only once before processing the first job, and cannot be altered between processes. The cost objective is the sum of regular costs on job completion times and service costs inversely proportional to the controllable service times. A finite set of subproblems, which can be solved by trust-region methods, are defined and their solutions are related to the optimal solution of the optimization problem under consideration. Exploiting these relationships, we introduce a two-phase search method which converges in a finite number of iterations. A numerical study is held to demonstrate the solution performance of the search method compared to a subgradient method proposed in earlier work.     

MXene-based composite electrodes for efficient electrochemical sensing of glucose by non-enzymatic method

A recently discovered 2D transition titanium metal carbides also called as MXenes (Ti₃C₂T_x)-based nanocomposite was prepared with Cu₂O through wet precipitation technique, and these materials were further developed as the electrode for sensing glucose by chronoamperometry technique. The prepared MXene-Cu₂O (Ti₃C₂T_x-Cu₂O) nanocomposite was characterized by XRD, FTIR, UV–Vis spectroscopy, FE-SEM, EDAX, and Raman spectroscopy. Morphological studies of the composites revealed that the micro-octahedral shape of Cu₂O is distributed on the surface of MXene with size larger than bare Cu₂O. Further, the prepared composite material was fabricated as a sensing probe, and the electrochemical activities were examined by cyclic voltammetric analysis (CV) and chronoamperometric (CA) methods. From the CV and CA investigation, the current response was higher for the composite than the bare material (Cu₂O & MXene) in the presence of glucose. The amperometric investigation of MXene-Cu₂O composite for the detection of glucose shows a broad linear range (0.01–30 mM) with a sensitivity of 11.061/μAmM cm^?2 and a detection limit of 2.83 μM. Further, the fabricated sensor exhibits good selectivity with interfering species like NaCl, fructose, sucrose, urea, ascorbic acid, lactose, short response time, stability, good reproducibility, and compatibility with human serum sample. From the investigation, the prepared MXene-Cu₂O composite is a good candidate for the direct detection of glucose molecules and is also well suitable for clinical diagnosis.     

Cyclotriphosphazene Fibre Reinforced Poly(benzoxazine-co-ε-caprolactam) Nanocomposites for Flame Retardant Applications

Cyclophosphazene nanotube(PZT) incorporated poly(benzoxazine-co-ε-caprolactam)(P(BZ-co-CPL)) nanocomposites were developed for improving flame retardant properties. The effects of PZT on the flammability properties of P(BZ-co-CPL) matrix were evaluated through UL-94 flammability test and limiting oxygen index(LOI). The UL-94 results of P(BZ-co-CPL)/PZT hybrid nanocomposites showed V-1 rating, whereas neat P(BZ-co-CPL) showed burning rating. The LOI values are increased from 25.4 to 31.4 for 1.5 wt% PZT incorporated P(BZ-co-CPL) nanocomposite systems. SEM was used to study the char morphology of P(BZ-co-CPL)/PZT after being exposed to UL-94 flammability test. Data from thermal studies indicate that the PZT incorporated P(BZ-co-CPL) systems possess better Tg and thermal degradation behavior when compared to the neat P(BZ-co-CPL). The values of dielectric constant are decreased with increasing temperature. From the values, it is ascertained that the P(BZ-co-CPL)/PZT systems exhibit stable dielectric behavior with regard to variation in temperature. The TEM images ascertain the uniform dispersion of PZT in the P(BZ-co-CPL) matrix.     

Formation of hexagonal shaped wurtzite zinc sulphide nano rods

Zinc sulfide nanorods with good photoluminescence have been successfully fabricated using a simple sol-gel process via ultrasonication, with mercaptoethanol as capping agent. The formation of ZnS nucleation, followed by subsequent growth, is significant in obtaining highly oriented ZnS nanorods. Temperature, time, and capping agent also proved to be significant factors in the growth of ZnS nanorods and greatly affect their photo luminescent properties. X-ray diffraction (XRD) analysis, low and high-resolution transmission electron microscopy (TEM & HRTEM), selected-area electron diffraction (SAED) pattern, and scanning electron microscopy (SEM) indicated that the ZnS nanorods were single crystal in nature and that they had grown up preferentially along the [0001] direction. This simple method of nucleation, followed by their successive growth, resulted in the development of an effective and low-cost fabrication process for high-quality ZnS nanorods with good photo luminescent properties that can be applied to luminescent sensors and optoelectronic devices.     

Controlled observation of nondegenerate cavity modes in a microdroplet on a superhydrophobic surface

We demonstrate controlled lifting of the azimuthal degeneracy of the whispering gallery modes (WGMs) of single glycerol-water microdroplets standing on a superhydrophobic surface by using a uniform electric field. A good agreement is observed between the measured spectral positions of the nondegenerate WGMs and predictions made for a prolate spheroid. Our results reveal fewer azimuthal modes than expected from an ideal spherical microdroplet due to the truncation by the surface. We use this difference to estimate the contact angles of the microdroplets.     

Blood flow in stenosed arteries with radially variable viscosity, peripheral plasma layer thickness and magnetic field

A novel approach of combined mathematical and computational models has been developed to investigate the oscillatory two-layered flow of blood through arterial stenosis in the presence of a transverse uniform magnetic field applied. Blood in the core region and plasma fluid in the peripheral layer region are assumed to obey the law of Newtonian fluid. An analytical solution is obtained for velocity profile and volumetric flow rate in the peripheral plasma region and also wall shear stress. Finite difference method is employed to solve the momentum equation for the core region. The numerical solutions for velocity, flow rate and flow resistance are computed. The effects of various parameters associated with the present flow problem such as radially variable viscosity, hematocrit, plasma layer thickness, magnetic field and pulsatile Reynolds number on the physiologically important flow characteristics namely velocity distribution, flow rate, wall shear stress and resistance to flow have been investigated. It is observed that the velocity increases with the increase of plasma layer thickness. An increase or a decrease in the velocity and wall shear stress against the increase in the value of magnetic parameter (Hartmann number) and hematocrit is dependent on the value of t. An increase in magnetic field leads to an increase in the flow resistance and it decreases with the increase in the plasma layer thickness and pulsatile Reynolds number. The information concerning the phase lag between the flow characteristics and how it is affected by the hematocrit, plasma layer thickness and Hartmann number has, for the first time, been added to the literature.