Catalytic Ketonization of Acetic Acid on Zn/Al Layered Double Hydroxides

The effects of CuO loading, reaction temperature, and surface gas velocity (U_g) on the photocatalytic reduction of NO have been determined in an annular flow type and a modified two-dimensional fluidized bed photoreactor. The optimum CuO loading was found to be 3.3 wt.% and NO degradation conversion in the modified two-dimensional fluidized bed photoreactor is more than 70% at 2.5 U_mf.     

Investigation into the rotational bands of ~(185)Pt with the particle-rotor model

Theoretical calculations have been performed for the ν9/2+[624](i13/2) and ν7/2-[503](f7/2) bands of 185Pt in the framework of particle-rotor model. The band properties of signature splitting and configuration mixing have been analyzed. The level energy and signature splitting before the band crossing can be well interpreted by introducing triaxiality. The positive-parity yrast band is pro posed to be dominated by the ν9/2+[624](i13/2) component, while the negative-parity band shows strong mixing of ν7/2-[5...     

Beyond the standard model: Working group report

This report summarises the activities of the working group on ‘Physics beyond the Standard Model’. The results of investigations in incorporatingR-parity in grand unification, the possibility of a light charged Higgs boson in extension of MSSM and radiative generation of neutral vector boson self-couplings within the MSSM are described. Also given is an account of activities in neutrino physics, namely a proposal for a study of the atmospheric muon anomaly in deep underground mines, a field theoretic study of neutrino oscillations and a mechanism to generate appropriate masses of three active plus one sterile neutrino species.     

乌鲁木齐淡水原生动物的种类及分布调查初报

几年来，在对乌鲁木齐淡水浮游生物调查中，对原生动物也作了初步研究．为了对乌鲁木齐的原生动物做一个较为系统的了解，从１９９４年５月～７月在９个样点采集水样，并对分属于植鞭纲、根足纲、辐足纲、寡膜纲、动基片纲及多膜纲等６个纲的１０９种原生物进行了鉴定．同时对各样点的主要生态因素及浮游原生动物的分布特征作了进一步的分析．     

Enhanced photocatalytic and adsorptive degradation of organic dyes by mesoporous Cu/Al2O3-MCM-41: intra-particle mesoporosity, electron transfer and OH radical generation under visible light

Mesoporous Cu/Al(2)O(3)-MCM-41 composite was synthesized by two step processes; in situ incorporation of high surface area mesoporous Al(2)O(3) (MA) into the framework of MCM-41 (in situ method) followed by impregnation of Cu(II) by incipient wetness method. The interesting thing is that starch was used for the first time as template for the preparation of high surface area MA. To evaluate the structural and electronic properties, these catalysts were characterized by low angle X-ray diffraction (LXRD), X-ray photoelectron spectroscopy (XPS), transmission electron microscopy (TEM), UV-vis DRS, FTIR and photoluminescent (PL) spectra. The various cationic dye such as methylene blue (MB), methyl violet (MV), malachite green (MG) and rhodamine 6G (Rd 6G) of high concentration 500 mg L(-1) were degraded and adsorbed very efficiently (100%) using the 5 Cu/Al(2)O(3)-MCM-41 composite within 30 and 60 min, respectively. The high and quick removal of such concerted cationic organic dyes and also mixed dyes (MB+MV+MG+Rd 6G) by means of photocatalysis/adsorption is basically due to the combined effect three characteristics of synthesized mesoporous 5 Cu/Al(2)O(3)-MCM-41 composite. These characteristics are intra-particle mesoporosity, electron transfer and ˙OH radical generation under solar light.     

A facile method for the synthesis of copper modified amine-functionalized mesoporous zirconia and its catalytic evaluation in C-S coupling reaction

A new copper modified amine functionalized zirconia has been synthesized by a co-condensation method using zirconium butoxide and aminopropyltriethoxy-silane (APTES) in the presence of a cationic surfactant CTAB followed by impregnation of copper. Nitrogen adsorption-desorption, X-ray powder diffraction, Fourier-transform infrared spectroscopy (FT-IR), (13)C nuclear magnetic resonance (NMR), scanning electron micrography (SEM), transmittance electron micrography (TEM), thermo gravimetric analysis-differential thermal analysis (TGA-DTA), X-ray photoelectron spectroscopy (XPS) and UV-vis DRS spectroscopic tools are used to characterize the materials. FT-IR and DRS results indicated the incorporation of Cu and amino groups on the surface of zirconia. This Cu-anchored mesoporous material acts as an efficient, reusable catalyst in the aryl-sulfur coupling reaction between aryl iodide and thiophenol for the synthesis of value added diarylsulfides.     

Threshold and compactification effects in GUTS

We review general results on threshold effects and their implications on GUTs in the context of LEP data. Among the blooming grand-desert models, threshold effects are computed in the presence of a single real scalar ζ (3, 0, 8) with M_ζ≃10¹⁰ GeV leading to experimentally testable predictions on the proton lifetimeτ _p in SU (5) and, in addition, small neutrino masses in SO (10) needed for the solar neutrino flux and the dark matter of the universe. The fine structure constant matching at M_Z is ensured by including threshold effects on the unification coupling. In the minimal SUSY SU (5) such effects at the GUT scale modify the prediction of the supersymmetric mass threshold near the TeV scale and the precision measurments of the Standard Model couplings at M_Z probe into the superheavy mass spectrum. Consequences of theorems proved very useful for threshold, compactification and multiloop effects are discussed. It is noted that in a class of GUTs the highest intermediate scale M_I above which G_224P becomes a good symmetry is not affected by the GUT threshold or compactification effects or multiloop contributions in the range M_I-M_U. But spontaneous compatification effects can decrease the intermediate scale drastically in models where parity and SU(2)_R breakings are decoupled. Low mass W_R-bsosns are permitted in models with decoupled parity and SU (2)_R breakings.     

Asymptotic bounds on pion form factor

A technique recently developed for inelastic electron proton scattering is applied for inelastic electron pion scattering. It is found that all the derivatives of off-shell form factor of pion nears=m _π ² and for largeQ ² are bounded from above, provided that the dispersion relation for the form factor requires no more than one subtraction. The elastic pion form factor is bounded by [lnQ ²] ^c /Q ², wherec is any positive constant.     

Dielectric and impedance spectroscopy of rare earth-based tungsten bronze ceramic

The ceramic oxide Na₂Pb₂Gd₂W₂Ti₄Ta₄O₃₀ (NPGWT) was synthesized by the solid solution route. The formation of compound was checked by using X-ray diffraction and scanning electron microscope study. It is observed from both the studies that the material is a single phase and highly dense. The preliminary temperature variation of the dielectric study reveals ferroelectric to paraelectric phase transition much above the room temperature. The polarization study of the material further confirms the presence of ferroelectricity in the studied compound. The transport property of the material was carried out by using the impedance spectroscopy technique. From both impedance and modulus analysis, it is confirmed that conduction mechanism in the material is due to the hopping motion of charge carrier. To strengthen the hopping motion of charge carrier in the material frequency dependence, ac conductivity is carried out.     

Solar Light Induced Photocatalytic Degradation of Pollutants over Titania Pillared Zirconium Phosphate and Titanium Phosphate

Titania pillared zirconium phosphate (ZrP) and titanium phosphate (TiP) were prepared by intercalating Ti (IV) isopropoxide sol in the interlayers of the mono sodium form of the corresponding metal phosphate. The sol-intercalated samples were activated at various temperatures and characterized by XRD, UV–vis DRS, FTIR, BET-surface area, BJH-pore size distribution and acid sites measurement. Basal spacing and surface area analyses revealed that highest amount of pillaring has taken place with 2 and 4 wt.% titania loading for ZrP and TiP, respectively. The photocatalytic degradation of 4-nitrophenol (4-NP), phenol, methylene blue (MB) and hexavalent chromium (Cr (VI)) was studied in aqueous solution over the neat as well as pillared materials under solar irradiation. Catalytic activity tests revealed that hexavalent chromium (Cr (VI)) and 4-nitrophenol (4-NP) were completely degraded under acidic conditions, whereas, the same was observed in almost neutral conditions for phenol and methylene blue (MB) over 0.6 g/L of catalyst.