Preparation of Some New Ethylene Glycol Monoesters and Mixed Diesters of Fatty Acids

Tri-(2-hydroxyethyl)-orthoborate, obtained by reaction of ethylene glycol with boric acid, was esterified with palmitic, stearic, arachidic, oleic, hydnocarpic, elaidic and stearolic acids. Pure monoesters were obtained on hydrolysis with water in high yields. Monoelaidate and monostearolate are reported for the first time. The monoesters were reacted with acyl chlorides to yield the mixed diesters, viz., oleostearate, oleopalmitate, oleoarachidate, oleoelaidate, oleostearolate, elaidohydnocarpate, stearocaproate and stearolaurate. Except oleostearate the other compounds are reported for the first time.     

Solar radiation climate of India

This paper presents the essential results of solar radiation measurements made at a network of thirteen stations in India during the last ten years. The basic records are of total integral wavelength global solar radiation and sky radiation on a horizontal surface, and of direct solar radiation and its spectral components, defined by the wavelength intervals λ < 525, 525–630, λ < 630, 525–710 and λ < 710 nm. Values of direct solar radiation at normal incidence and on horizontal and vertical surfaces have also been calculated from continuous records of the global and sky radiation on a horizontal surface at all 13 stations. The spatial and seasonal variations of direct solar radiation, global solar, and sky radiation are discussed. Results are also presented of special direct solar observations made at a few high altitude stations in Kashmir in 1969.     

New III-V double-heterojunction laser emitting near 3.2 μm

Double heterostructure lasers based on the InAsSbP/InAsSb system have been prepared by liquid phase epitaxy. They operate at 78 K near 3.2 μm, with a threshold current density of 4.5 kA/cm² in pulsed conditions. The characteristic temperature T₀ is 30 K     

Negative bias temperature instability in n-channel power VDMOSFETs

Negative gate bias is used in some applications for faster switching off the n-channel MOS devices. It is shown in this study that NBT stress-related instability in commercial n-channel power VDMOSFETs could be actually more serious than in corresponding p-channel devices. NBT stress is found to create equal V_T shifts in both device types, whereas the subsequent positive bias annealing results in more serious overall V_T instability in n-channel devices. The changes in the densities of stress-induced interface traps in two device types are equal as well, but significant amounts of NBT stress-induced border traps are only found in n-channel devices. All the results are discussed in terms of hydrogen reaction and diffusion model.     

Closed-Form Analysis of Various Diversity Techniques for Multiband OFDM UWB System Over Log-Normal Fading Channels

Wireless Personal Communications - In this paper, we investigate the effect of multipath fading on the combined signal-to-noise ratio (SNR) in conjunction with multiband orthogonal frequency...     

Deionization shocks in crossflow

Shock electrodialysis is a recently developed electrochemical water treatment method that shows promise for water deionization and ionic separations. Although simple models and scaling laws have been proposed, a predictive theory has not yet emerged to fit experimental data and enable system design. Here, we extend and analyze existing “leaky membrane” models for the canonical case of a steady shock in crossflow, as in recent experimental prototypes. Two-dimensional numerical solutions are compared with analytical boundary-layer approximations and experimental data. The boundary-layer theory accurately reproduces the simulation results for desalination, and both models predict the data collapse of the desalination factor with dimensionless current, scaled to the incoming convective flux of cations. The numerical simulation also predicts the water recovery increase with current. Nevertheless, neither approach can quantitatively fit the transition from normal to over-limiting current, which suggests gaps in our understanding of extreme electrokinetic phenomena in porous media.     

Facile synthesis and characterization of ZnO NPs,ZnO/CdO and ZnO/SnO2 nanocomposites for photocatalytic degradation of Eosin Yellow and Direct Blue 15 under UV light irradiation

Journal of Materials Science: Materials in Electronics - In the present report, the synthesis of ZnO NPs, ZnO/CdO NCs, and ZnO/SnO2 NCs was successfully achieved by co-precipitation technique. The...     

Magnetically Guided Self‐Assembly and Coding of 3D Living Architectures

In nature, cells self‐assemble at the microscale into complex functional configurations. This mechanism is increasingly exploited to assemble biofidelic biological systems in vitro. However, precise coding of 3D multicellular living materials is challenging due to their architectural complexity and spatiotemporal heterogeneity. Therefore, there is an unmet need for an effective assembly method with deterministic control on the biomanufacturing of functional living systems, which can be used to model physiological and pathological behavior. Here, a universal system is presented for 3D assembly and coding of cells into complex living architectures. In this system, a gadolinium‐based nonionic paramagnetic agent is used in conjunction with magnetic fields to levitate and assemble cells. Thus, living materials are fabricated with controlled geometry and organization and imaged in situ in real time, preserving viability and functional properties. The developed method provides an innovative direction to monitor and guide the reconfigurability of living materials temporally and spatially in 3D, which can enable the study of transient biological mechanisms. This platform offers broad applications in numerous fields, such as 3D bioprinting and bottom‐up tissue engineering, as well as drug discovery, developmental biology, neuroscience, and cancer research.