Electroproduction of neutral pions at energies above the resonance region

The reaction e p→e'pπ⁰ has been measured at W=2.55 GeV a fixed electron scattering angle of 10.3°. Two magnetic spectrometers and a lead glass hodoscope were used to detect all four final state particles. Electroproduction cross sections in the t range ?0.15 to ?1.4 (GeV/c)² at q² = ?0.22, ?0.55 and ?0.85 (GeV/c)² are presented. Above |t|=0.6 (GeV/c)² the cross sections are considerably smaller than those for photoproduction.     

An improved synthesis of anticancer benzothiopyranoindazoles. An efficient large-scale β-aminoethylation procedure

Improved processes for the synthesis of bulk quantities of the benzothiopyranoindazole clinical agent CI-958 and A-ring congeners is reported. The process chosen for scale-up operations achieves β-aminoethylation of an anilino precursor via a three-step sequence (acylation, reduction, deprotection) starting from N-(trityl)glycine. Detailed analytical data are reported for the target compounds and most intermediates, and detailed spectroscopy is given for CI-958.     

Preparation and characterization of the first stable organozinc hydride,PhZn2H3

The first stable organozinc hydride PhZn₂H₃ has been obtained by treatment of Ph₂ Zn with LiAlH₄ in THF solution; the compound is characterized by the IR spectrum, X-ray powder diffraction pattern and DTA—TGA.     

Solution-Phase and Magnetic Approach towards Understanding Iron Gall Ink-like Nanoassemblies

Metal-containing tubes: The structures of several iron-containing C-methylpyrogallol[4]arene (PgC(1) ) nanoassemblies were studied in both the solid and solution phases. The nanoassemblies have a tubular architecture with the iron as part of the framework (see picture; gray C, red O, turquoise/blue Fe), and magnetic analysis suggests a canted or spiral arrangement of the iron centers.     

Computational strategies for non-convex multistage MINLP models with decision-dependent uncertainty and gradual uncertainty resolution

In many planning problems under uncertainty the uncertainties are decision-dependent and resolve gradually depending on the decisions made. In this paper, we address a generic non-convex MINLP model for such planning problems where the uncertain parameters are assumed to follow discrete distributions and the decisions are made on a discrete time horizon. In order to account for the decision-dependent uncertainties and gradual uncertainty resolution, we propose a multistage stochastic programming model in which the non-anticipativity constraints in the model are not prespecified but change as a function of the decisions made. Furthermore, planning problems consist of several scenario subproblems where each subproblem is modeled as a nonconvex mixed-integer nonlinear program. We propose a solution strategy that combines global optimization and outer-approximation in order to optimize the planning decisions. We apply this generic problem structure and the proposed solution algorithm to several planning problems to illustrate the efficiency of the proposed method with respect to the method that uses only global optimization.     

Enhanced colorless and broadcast capable symmetrical 10-Gbps bidirectional transmission in WDM-PON using RSOA and EAM

Here we proposed a novel architecture of wavelength division multiplexed-passive optical network (WDM-PON) in which the downlink unicast data, broadcast data and uplink unicast data transmission is possible with the symmetric data rate of 10 Gbps. At remote node (RN) cyclic wavelength routing property of array waveguide grating (AWG) and power splitting capacity of power splitter is used in the architecture so that broadcast channel can be overlaid on downlink unicast channels. At ONU carriers sent from central office (CO) is reused for upstream data transmission with the help of integration of a reflective semiconductor amplifier (RSOA) and an electro-absorption modulator (EAM) so there is no need of extra laser sources at ONUs which makes them colorless. EAM can be operated at very high speed; a modulation bandwidth of tens of GHz can be achieved. Broadcast channel causes a limited interference with downlink and uplink unicast channels so it does not affect the system performance. Since each channel has different wavelength so NRZ data is used which eliminates expensive DPSK receivers and detection becomes very easy. Simulation is performed with all channels having data rate of 10 Gbps having acceptable performance.     

Vibrational Mean Amplitudes of XY3 Pyramidal Molecules

The vibrational mean amplitudes for bonded as well as for nonbonded distances have been evaluated for AsP₃, SbP₃, and PAs₃ at temperatures : T = 0^oK, T = 298.15^oK and T=500 ^oK using recent vibrational data. The results have been briefly discussed.     

Evidence for electret polarization in polyoxymethylene

It has been found that under certain experimental conditions, polyoxymethylene films undergo a microscopic as well as macroscopic polarization resulting in electret formation. Thermally stimulated discharge (TSD) currents have been measured for polyoxymethylene film electrets of 100 μM prepared at various polarizing fields and polarization temperatures. Experimental evidence like the shift of the discharge current peak with polarization temperature, and a nonlinear dependence of the accumulated charge on field strength suggests the formation of a space charge and interfacial polarization. The observed TSD peak at 130°C coincides with the α -relaxation temperature in low-frequency dielectric measurements. Activation energies and relaxation times have been calculated on the basis of the experimental data.     

A Direct Approach to Insulin Isotherm Analysis in Reversed Phase Chromatography

There is a need to demonstrate the application of a simple isotherm method and a process chromatography optimization methodology with its approximations and assumptions that is useful when quick application is required. This paper presents an explanation of a basic procedure for the optimization of the acetonitrile concentration under isocratic condition with insulin as the model compound, using the retention time method for single component isotherm measurement. The retention time method was used to measure the adsorption isotherm over the concentration range of 26–29% acetonitrile. The assumption of a single component isotherm for insulin is appropriate in this study since the shift of the peak front due to a tag-along effect of the des-amido insulin degradation product is minimal. This RTM method assumes a Langmuir isotherm model. This model is an accurate representation under these experimental conditions as revealed by the shape of the measured shock front time as a function of amount loaded. Analysis of the isotherm results shows the ‘a’ parameter decreases with increasing volume per cent acetonitrile and the column saturation capacity decreases with increasing volume per cent acetonitrile. The cycle time is represented by ‘a’ parameter and the loading factor by the column saturation capacity. Since the ‘a’ parameter increases with decreasing volume per cent acetonitrile, the cycle time increases and the production rate decreases. On the other hand, the column saturation capacity increases with decreasing volume per cent acetonitrile; therefore, the optimum loading factor increases, thus the production rate increases. This trade-off leads to an optimum acetonitrile concentration at low k′ until practical operational limits are achieved.