Summability of Laguerre series at the pointx=0

In this paper, the authors prove a theorem on matrix summability of Laguerre series at the point x=0. Various results on Casàro, Nörlund and generalized Nörlund summability method have been deduced.     

Forward scattering in systems with non-central potentials: an analysis of the infinite order sudden approximation

The l-labelled version of the IOS is re-examined in detail. It is shown that recent severe criticism of the method, based on studies of a system with a long-range attractive anisotropy and spherically symmetric hard core and assuming a weak anisotropy and straight-line Trajectories, is unjustified.     

Quantum interference effect in laser patterned BSCCO thick film

DC SQUID structure consisting of two microbridges and a circular hole was patterned on BSCCO thick film using laser ablation technique. Quantum interference effects on these patterned films were studied at fixed biasing current by applying changing magnetic field. The SQUID with 100 μm × 70 μm microbridges showed noisy and irregular V-B behaviour whereas the SQUID containing smaller microbridges showed better V-B characteristic. Temperature dependence of the I-V and V-B characteristics of the SQUID is also reported.     

Effect of three-body interactions on electronic polarizabilities and photoelastic behaviour of partially covalent crystals

Summary We have investigated the effect of three-body interactions on the photoelastic behaviour and the electronic polarization of silver, thallium and copper halides, which are partially covalent in character and possess three different crystall structures. The cation, anion and molecular polarizabilities calculated in their crystalline state seem to be reliable as they follow a systematic trend. Our calculated values of the strain derivatives of the electronic dielectric constants are much closer to their experimental data than those obtained by earlier workers. To speed up publication, the authors of this paper have agreed to not rceive the proofs for correction.     

An exactly solvable quarkonium model and lower bounds on 3 p J decay rates

The exact 1P-state wavefunction R _1P (r) is obtained for the potential     

Switching liquid morphologies on linear grooves

The morphology of liquids confined to linear micrometer-sized grooves of triangular and rectangular cross section is studied for different substrate wettabilities. Depending on the wettability and exact geometry, either droplike morphologies or elongated liquid filaments represent the generic equilibrium structures on the substrate. Upon changing the apparent contact angle of aqueous drops by electrowetting, we are able to trigger the transition between elongated filaments and droplets. In the case of rectangular grooves, this transition allows us to advance liquid reversibly into the grooves while crossing a certain threshold contact angle. In triangular grooves, however, these elongated filaments undergo a dynamic instability when the contact angle returns to a value above the filling threshold. The different filling and drainage behavior is explained by specific aspects of the triangular and rectangular groove geometry.     

Kinetics of epoxidation by a Musa paradisiaca chloroperoxidase

Epoxidations of indene, styrene, 2-chlorostyrene, 3-chlorostyrene, 4-chlorostyrene, 4-bromostyrene, and naphthalene using Musa paradisiaca plant juice chloroperoxidase in the presence of H₂O₂ and t-butyl peroxide as oxidants have been studied. The steady-state kinetic parameters, K_m and k_cat of the enzyme for the above substrates have been determined. The temperature and pH optima of the epoxidation are 25°C and 6.2, respectively. The yield of styrene oxide in the presence of H₂O₂ was 44%. The results show that M. paradisiaca plant juice chloroperoxidase is a potential biocatalyst for organic epoxidation reactions.     

Treatment of sugar processing industry wastewater using copper electrode by electrocoagulation: Performance and economic study

This paper demonstrates the use of copper electrode for the treatment of sugar processing industry wastewater (SPIW) in terms of chemical oxygen demand (COD) by applying electrocoagulation (EC) method. EC process was carried out in batch mode with electrode effective area of 0.0112 m², supplied current intensity (CI) of 44.64 A/m² - 223.21 A/m², electrode gap (EG) of 0.5–2.5 cm, electrolyte (NaCl) dose (ED) of 0.5–2.5 g/L to treat SPIW with initial chemical oxygen demand (COD) of 6000 mg/L. The maximum COD removal 73% of SPIW is achieved at optimized condition of SPIW pH: 7, CI: 89.28 A/m², EG: 1.5 cm & ED: 1.5 g/L. Sludge and scum generated during EC process were characterized by FTIR, TGA/DTA/DTG, proximate & ultimate analysis to find its applicability and their disposal. Additionally, economic study of EC treatment process at optimum condition suggest treatment cost was 11.2 US$/m³ and it indicate economic results as comparison to other available treatment processes.     

Mathematical Modeling of Nylon 6/6,6 Copolymerization: Beneficial Influence of Comonomers on Degree of Polymerization in Batch Reactor

A model is developed for hydrolytic copolymerization of caprolactam with hexamethylene diamine (HMD) and adipic acid (ADA) in a batch reactor to produce nylon 6/6,6 copolymer. The reaction mechanism includes hydrolysis of caprolactam and cyclic dimer, polycondensation, polyaddition, transamidation, and ring formation via end biting and back biting. The catalyzing effect of carboxyl groups is accounted for using kinetic parameters from the literature. Model predictions are compared with low‐temperature literature data before simulating reactor conditions of industrial interest. The model predicts a higher degree of polymerization (DP) for nylon 6/6,6 copolymer compared to nylon 6 and 6,6 homopolymers produced using the same reactor conditions. Dynamic changes in concentrations of water, caprolactam, HMD, ADA, and end groups are tracked and used to explain the positive influence of comonomers on reaction rates and DP. Insights gained from this model will form a useful basis to build future models of continuous industrial reactors.