Copper Nanoparticles in Ionic Liquid: An Easy and Efficient Catalyst for Selective Carba-Michael Addition Reaction

In this paper, we wish to report a novel synthesized copper nanoparticles in an ionic liquid employed as a catalyst for Michael addition between active methylene compound and α, β-unsaturated compounds to give corresponding compounds in excellent yield and in shorter reaction times.      

Structural, optical and electrical characterization of selenium sulphide nanostructured thin film

Thin film of selenium sulphide (Se₇₅S₂₅) has been prepared using inert-gas consolidation (IGC) method and micro-structural, optical and electrical measurements were carried out on the film. Scanning electron microscopy (SEM) studies show that the deposited film is well adherent and grains are uniformly distributed over the surface of the substrate. X-ray diffraction (XRD) analysis shows that the film is polycrystalline nature with single phase and crystallizes in the orthorhombic structure. The field emission transmission electron microscope (FETEM) revealed the uniform dispersion and an average particle size of 20 nm. Analysis of the optical absorption data indicates that the optical band gap E_opt of this film obeys Tauc's relation for the allowed non-direct transition with energy gap is 2.48 eV. Electrical conduction measurements also show the presence of two distinct phases of the materials and characteristic changes in transport properties due to the nanosize of the materials.     

Anomalous specific heat of the La-Ge system

The specific heat of the orthorhombically distorted -ThSi₂-type La-Ge intermetallic compound system has been measured in the temperature range 0.07 T 10 K. An anomalous behavior of the lattice part of the specific heat has been discovered. The specific heat data are analyzed and discussions are given, with particular attention to the superlattice structure observed in these compounds.     

Natural vs. Synthetic Phosphate as Efficient Heterogeneous Compounds for Synthesis of Quinoxalines

Natural phosphate (NP) and synthetic fluorapatite phosphate (SFAP) were proposed as stable, inexpensive, readily available and recyclable catalysts for the condensation of 1,2-diamines with 1,2-dicarbonyls in methanol to afford quinoxaline at room temperature. NP provided as high as 92–99% yield for quinoxalines in short reaction times (i.e., 1–45 min), while SFAP created quinoxalines with 87–97% yield in 60–120 min. From the chemical analyses, X-ray fluoresecency, X-ray diffraction, energy dispersive X-ray and Fourier-transform infrared spectroscopy methods, two main phases (CaO, P₂O₅) appeared in NP together with other low content phases (SiO₂, Fe₂O₃). Compared to other phases, apatite (CaO and P₂O₅ as Ca10(PO₄)₆) played a major role in the catalytic activity of NP. SFAP with similar Ca/P atomic ratio showed a relatively lower catalytic activity than NP for the condensation of 1,2-diamine with 1,2-dicarbonyl in methanol at ambient temperature. To investigate the recyclability of catalysts, the surface properties of NP and 6-recycled NP were investigated using scanning electron microscopy, energy dispersive X-ray and Brunauer–Emmett–Teller and Barrett–Joyner–Halenda methods. Some differences were observed in NP and 6-recycled NP’s particle size, surface area, the volume and size of pores, and the content of elements; nevertheless, the use–reuse process did not noticeably change the catalytic property of NP.     

Shelf life prediction software finds application with ethical drugs

Applications for approval of new ethical drugs require that stability studies be completed prior to submission to the FDA. If the company chooses packaging which is found (by conventional storage testing) to provide insufficient barrier protection, new packaging must be identified and storage tests re‐run. This iterative process must be repeated until packages are found which provide adequate protection. If the chosen package is over‐protective, stability studies show adequacy, but do not identify over‐protection. A third option is to employ a myriad of test packs which impacts negatively on facilities and personnel, and is expensive and time‐consuming. Package optimization requires additional testing and re‐submission of the New Drug Application (NDA). A combination of analysis and computer shelf life predictions can be utilized to develop optimal packaging without such repetitive testing. A study was initiated with Searle to apply analytical evaluations and shelf life simulations to identify appropriate packaging for new drugs prior to the initiation of conventional stability testing. The procedure used analytical evaluations of two ethical drugs (without package protection) to identify the susceptibilities of the product to storage‐induced changes. The analytical results were then plugged into a computer shelf life modelling program which identified barrier requirements which would provide the protection found to be required for the drug product. This then defined the packaging needs. The efficacy of this modelling approach was confirmed for one product by conducting conventional stability studies with packaging materials which satisfied the barrier requirements which had been specified by the computer simulations. Storage studies for the second product are in process, and performance to date supports the predicted values. Copyright © 1999 John Wiley & Sons, Ltd.     

An efficient numerical technique based on the extended cubic B-spline functions for solving time fractional Black–Scholes model

Financial theory could introduce a fractional differential equation (FDE) that presents new theoretical research concepts, methods and practical implementations. Due to the memory factor of fractional derivatives, physical pathways with storage and inherited properties can be best represented by FDEs. For that purpose, reliable and effective techniques are required for solving FDEs. Our objective is to generalize the collocation method for solving time fractional Black–Scholes European option pricing model using the extended cubic B-spline. The key feature of the strategy is that it turns these type of problems into a system of algebraic equations which can be appropriate for computer programming. This is not only streamlines the problems but speed up the computations as well. The Fourier stability and convergence analysis of the scheme are examined. A proposed numerical scheme having second-order accuracy via spatial direction is also constructed. The numerical and graphical results indicate that the suggested approach for the European option prices agree well with the analytical solutions.

     

Developing a well-being monitoring system—Modeling and data analysis techniques

This paper describes how complex data analysis algorithms are being employed to develop a new generation of telecare aimed at helping older people remain living more independently in their own homes for longer. The paper begins by explaining why governments throughout the world are encouraging the development and deployment of new telecare solutions—due in the main to a gradual but constant shift in demographics. Details of a new generation of telecare called ‘well-being monitoring’ being developed in the UK under the DTI (Department of Trade and Industry) NWTM initiative are provided, DTI [1]. The paper describes how the DTI funded ‘Care in the Community Centre’ led by BT, has developed a concept model to represent an individual's well-being. The paper goes on to provide an in depth explanation of the Intelligent Data Analysis techniques to be used for monitoring changes in well-being.     

Development of a laboratory model of SSSC using RTAI on Linux platform

This paper presents the implementation of Static Synchronous Series Compensator (SSSC) controller on Real Time Application Interface (RTAI) for Linux Operating System (OS). RTAI provides real-time capability to Linux General Purpose Operating System (GPOS) over and above the capabilities of non real-time Linux environment, e.g. access to TCP/IP, graphical display and windowing systems, file and database systems. Both Type II controllers, DC voltage and current scheduling controllers, are implemented in RTAI. To create a user friendly environment, Graphical User Interface (GUI) is developed in Linux OS in user space (non real-time) using a software available from Quasar Technologies (Qt). The controller is tested on a small scale laboratory model of a Voltage Source Converter (VSC) connected in series with a transmission line. The real time controller performs well in both inductive and capacitive regions.     

Dielectric parameters and a.c. conductivity of pure and doped poly (methyl methacrylate) films at microwave frequencies

Dielectric properties of pure and doped poly (methyl methacrylate) (PMMA) films at microwave frequency, 8.92 GHz, have been studied at 35°C. Iodine, benzoic acid and FeCl₃ have been used as dopants. The losses in doped films are found to be larger than in pure PMMA films. The increased losses account for increased a.c. conductivity in doped films. The increase in conductivity is accounted due to creation of additional hopping sites for the charge carriers in doped samples. The dielectric data has also been used to evaluate optical constants, absorption index (K) and refractive index (n) of the films.     

Synthesis of calcium‐containing methacrylate resin

The calcium salt of p‐aminobenzoic acid [p‐ABA(Ca)] was reacted with epichlorohydrin to yield the multifunctional epoxy resin. The epoxy resin was characterized by IR spectroscopy, epoxy equivalent, calcium estimation, high performance liquid chromatography (HPLC) and refractive index. The epoxy resin was further reacted with methacrylic acid to yield the calcium containing methacrylate resin, which was characterized by IR, hydroxyl value, iodine value, HPLC and refractive index. © 2001 John Wiley & Sons, Inc. J Appl Polym Sci 82: 2342–2346, 2001