Structural phase transition in substituted La2CuO4 and Pr2CuO4−y

The structural phase transition from orthorhombic (T) phase to tetragonal (T′) phase in substituted La_2−x R _x CuO₄ (R = Pr, Nd, Sm, Eu and Gd) and T′ to T-phase in Pr_2−x M _x CuO_4−y (M = Sr, Ca) has been studied by X-ray diffraction technique. The T-phase of La₂CuO₄ is transferred to T′ phase abruptly atx=0.8, 0.4, 0.4, 0.3 and 0.4 respectively for substitution of Pr, Nd, Sm, Eu and Gd for La in La₂CuO₄ without evidence of the T* phase. The T′ structure of Pr₂CuO₄ (x = 0.0) gets transformed to the T* structure at 30% Ca doping (x=0.6) and then to the T structure at 50% Ca doping (x=1.0), while for Sr-contentx=0.0, 0.4 and 1.0 it shows T′, T* and T structure respectively.     

A Two‐Dimensional Coordination Compound as a Zinc Ion Selective Luminescent Probe for Biological Applications

A 2D coordination compound {[Cu₂(HL)(N₃)]?ClO₄}_∞ ( 1 ; H₃L=2,6‐bis(hydroxyethyliminoethyl)‐4‐methyl phenol) was synthesized and characterized by single‐crystal X‐ray diffraction to be a polymer in the crystalline state. Each [Cu₂(HL)(N₃)]⁺ species is connected to its adjacent unit by a bridging alkoxide oxygen atom of the ligand to form a helical propagation along the crystallographic a axis. The adjacent helical frameworks are connected by a ligand alcoholic oxygen atom along the crystallographic b axis to produce pleated 2D sheets. In solution, 1 dissociates into [Cu₂(HL)₂(H₃L)]?2H₂O ( 2 ); the monomer displays high selectivity for Zn²⁺ and can be used in HEPES buffer (pH 7.4) as a zinc ion selective luminescent probe for biological application. The system shows a nearly 19‐fold Zn²⁺‐selective chelation‐enhanced fluorescence response in the working buffer. Application of 2 to cultured living cells (B16F10 mouse melanoma and A375 human melanoma) and rat hippocampal slices was also studied by fluorescence microscopy.     

A glucose electrode based on carbon paste chemically modified with a ferrocene-containing siloxane polymer and glucose oxidase,coated with a poly(ester-sulfonic acid) cation-exchanger

A carbon-paste chemically modified with glucose oxidase and a ferrocene-containing siloxane polymer was further modified by coating the electrode surface with a poly(ester-sulfonic acid) cation-exchanger, Eastman AQ-29D. The polymer is obtained as a homogeneous aqueous dispersion at pH 5–6; when dried, the polymer coating is not water-soluble. The coating was shown not to be detrimental to the enzyme activity but to prevent electrochemically active anionic interferents such as ascorbate and urate from reaching the electrode surface. The polymer coating also prevented glucose oxidase from leaking out of the carbon paste into the contacting solution and protected the electrode surface from fouling agents present in urine and bovine serum albumin. Uncoated electrodes lost some 10-2-15% of their original response to glucose after storage in buffer for three weeks whereas the response of the coated electrodes remained constant. Calibration curves for glucose were strictly linear up to about 5 mM for uncoated and up to 20 mM for coated electrodes. The response current to glucose was not decreased after coating.     

Optimizing the rapidity limit for nuclear stopping in intermediate energy heavy-ion collisions

A systematic study regarding the role of participant matter and spectator matter in nuclear stopping using isospin-dependent quantum molecular dynamics model is presented. The simulations have been carried out with soft equation of state along with the reduced isospin-dependent cross section to study the effect of different types and sizes of rapidity distributions on nuclear stopping for the whole colliding geometry with density-dependent symmetry energy. In addition to that, we attempt to investigate the role of isospin in heavy-ion collisions by calculating the individual contribution of neutrons and protons in nuclear stopping for different systems having different isotopic content.     

Observation of field induced anomalous quantum criticality in Ce0.6Y0.4NiGe2 compound

We report the results of our investigation of magnetization and heat capacity on a series of compounds Ce${}_{1?x}$Y_xNiGe₂ ($x=0.1,0.2\text{ and }0.4$) under the influence of external magnetic field. Our studies of the thermodynamic quantity $?\mathrm{d}M/\mathrm{d}T$ on these compounds indicate that magnetic frustration persists in Ce_0.9Y_0.1NiGe₂, as also reported for the parent compound CeNiGe₂. The weak signature of this frustration is also noted in Ce_0.8Y_0.2NiGe₂, whereas, it is suppressed in Ce_0.6Y_0.4NiGe₂. Heat capacity studies on Ce_0.9Y_0.1NiGe₂ and Ce_0.8Y_0.2NiGe₂ indicate the presence of a new magnetic anomaly at high field which indicates that quantum criticality is absent in these compounds. However, for Ce_0.6Y_0.4NiGe₂ such an anomaly is not noted. For this later compound, the magnetic field (H) and temperature (T) dependence of heat capacity and magnetization obey $H/T$ scaling above critical fields. However, the obtained scaling critical parameter (δ) is 1.6, which is away from mean field value of 3. This deviation suggests the presence of unusual fluctuations and anomalous quantum criticality in these compounds. This unusual fluctuation may arise from disorderness induced by Y-substitution.     

A Self-Healing Metal–Organic Hydrogel for an All-Solid Flexible Supercapacitor

A zinc containing metal–organic gel (Zn-MOG) with embedded free ions, which exhibits self-healing properties, has been synthesized for application in supercapacitors. The activated carbon-based flexible supercapacitor device with the MOG electrolyte has a broad potential window of 2.1 V, with high retention of specific capacitance compared to the traditional polyvinyl alcohol (PVA)-based gel. The Zn-MOG does not require an additional electrolyte. The sodium and sulphate ions embedded in the MOG are sufficient enough for the charge storage.     

Cost Optimization Technique for Quantum Circuits

In this paper, an attempt is made to present a method of quantum cost minimization or optimization technique for quantum reversible circuits using proposed merger rules in Exclusive Sum of Product (ESOP) method. These modified ESOP methods are used to minimize the quantum circuits. We found that the quantum cost is drastically decreased than the previous ESOP method. It will be easy to find the quantum cost and quantum gate optimized quantum circuits implementation. It will also reduce quantum error while the quantum circuit is executed in real quantum processor.

     

Solvation Dynamics of a Radical Ion Pair in Micro‐Heterogeneous Binary Solvents: A Semi‐Quantitative Study Utilizing MARY Line‐Broadening Experiments

This work aims at elucidating the mechanism of solvation of a radical ion pair (RIP) in a micro‐heterogeneous binary solvent mixture using magnetically affected reaction yield (MARY) spectroscopy. For the exciplex‐forming 9,10‐dimethylanthracene/N,N‐dimethylaniline system a comparative, composition‐dependent MARY line‐broadening study is undertaken in a heterogeneous (toluene/dimethylsulfoxide) and a quasi‐homogenous (propyl acetate/butyronitrile) solvent mixture. The half‐saturation field extrapolated to zero‐quencher concentration, B_1/2, and the self‐exchange rate constants are analyzed in the light of solvent dynamical properties of the mixtures and a dielectric continuum solvation model. The dependence of B_1/2 on the solvent composition is explained by cluster formation giving rise to shortened RIP lifetimes. The results are in qualitative agreement with the continuum solvation model suggesting that it could serve as a theoretical basis for quantitative modeling.     

Modification of Poly(2, 6-dimethyl-1,4-phenylene Oxide): Phosphorylation Studies

Side chain bromination of poly(2,6-dimethyl-1,4-phenylene oxide) (PPO) was carried out by using N-bromosuccinimide followed by phosphorylation of the bromo derivative with triethyl phosphite. Optimum conditions for minimum gel formation have been established. The products have been characterized by 'H-NMR and IR studies. Thermal behavior was investigated by thermogravimetry and differential scanning calorimetry in an air nitrogen atmosphere. Phosphorylated PPO starts to lose weight at 200°C, but the char yield increases with an increase in the phosphorus content of the polymer.