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A novel potyvirus we call Gazar virus Y (GVY) was isolated from diseased carrot plants in Egypt. It produced symptoms similar to those caused by carrot virus Y. Its particles were visualized in leaf extracts using negative stain, and leaf tissues from carrot plants infected with GVY had many ultra-structural differences from healthy ones. Chemical analyses of healthy and infected carrot roots showed that carrot roots infected with GVY had increased dry weight and decreased moisture, total ash, total carbohydrates, total fibres, vitamin C, β-carotene, vitamin A and the minerals of K, Mg, Na, P and Ca compared to the healthy carrot roots. Molecular methods, including reverse transcription-polymerase chain reaction (RT-PCR), were used to amplify a 335 bp cDNA fragment transcribed from infected plant extracts using degenerate oligonucleotide primers specific for potyviruses. The amplified cDNA was cloned into pGEM®-T Easy vector, and transformed into Escherichia coli (E. coli) strain DH5α . The recombinant inserts were sequenced. The nucleotide sequence (GenBank Accession Code GQ148776) was matched against viral nucleotide sequences in the GenBank database. It is most closely related to viruses of the celery mosaic virus group of potyviruses, but is distinct from all and represents a sister lineage to all others described so far.

Infrared spectroscopic studies were performed for poly(methyl methacrylate) samples doped with an organic ligand (N,N-dioxaloyl benzenesulphonyl-N,N-dioxaloylthiocarbazide) and its cobalt (II) complex during gamma radiolysis after extraction of the dopant. There are no drastic changes in the IR-absorption band positions, but noticeable changes in the intensities are found. The relative transmission of IR-absorption bands such as bands at 750, 840, 1065, and 1388 cm−1 were measured relative to the transmission of the carbonyl group band at 1717 cm−1. The degradation and recombination mechanism of different groups in the polymeric chain or backbone during radiolysis are suggested by the behavior of the relative transmission data for each group with increasing exposure dose. The tacticity of the PMMA sample was unchanged during radiolysis and was found to be syndiotactic. This fact is confirmed by measuring the IR J-values for different PMMA samples before and after irradiation. The protection effic...

Protection of some poly (methylmethacrylate) samples against gamma rays has been investigated in the absence and presence of Tetraoxalylsulfanilamide and its Cobalt (II) complex. The pure PMMA (without additives), PMMA-Ligand and PMMA - Cobalt (II) complex composite samples were irradiated with gamma rays for different exposure doses (5, 15, 25, 35, 50, 75 and 100 KGy). Viscosity average molecular weight (Mv-values) and thin layer chromatographic measurements were carried out after each irradiation dose. The maximum protection against gamma ray is found when 3% of the organic ligand or its Cobalt (II) complex is used in the polymer matrix. The radiation chemical yield for chain scission (Gs) is calculated and has its lower values in the case of the organic ligand, which means that the protection is stronger in the case of the organic ligand than its Cobalt (II) complex. From TLC studies, it is noticed that both the Rf-values and polydispersity of the PMMA samples increase with increasing exposure dose.

The temperature dependence of electron spin resonance (ESR) has been measured to clarify the origin and nature of paramagnetic states responsible for the observed ESR signal in P+-implanted C60 films. Also, the temperature dependence of electrical conductivity was made and compared with ESR linewidths to detect the transport mechanism in these films. The ESR experiments were performed at 9.4 GHz in a wide temperature range from 3.7 to 300 K. The temperature dependence of the ESR signal intensity and spin susceptibility revealed that the unpaired spin follows the Curie law at T 20 K. The Curie behavior of the spin susceptibility results from localized dangling bond electrons, while a deviation occurs due to delocalization and excitation of electrons into states as the temperature increases. The temperature dependence of linewidths indicates that the spin mobility occurs by hopping, taking into account that the electron–phonon interaction as spin relaxation me...

Infrared (IR) spectroscopy studies were performed for poly(methyl methacrylate) (PMMA) samples doped with an organic ligand or its cobalt(II) complex after the extraction of the dopant during γ-radiolysis. There were no drastic changes in the IR absorption band position, but noticeable changes in the intensities were found. The relative transmission of IR absorption bands, such as those at 750, 840, 1065, and 1388 cm−1, were measured according to the transmission of the carbonyl group band at 1717 cm−1. The degradation and recombination mechanism of different groups in the polymeric chain or backbone during radiolysis could be explained by the behavior of the relative transmission data for each group with increasing exposure dose. The tacticity of the PMMA samples was unchanged during radiolysis, and they were found to be syndiotactic. This was confirmed by the IR J values for different PMMA samples before and after irradiation. The protection efficiency of the organic ligand and its cobalt(II) complex was also investigated, and it was found that the organic ligand was more protective than the cobalt(II) complex for PMMA samples against γ-rays. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 91: 1937–1950, 2004

Electron paramagnetic resonance (EPR) measurements have been performed to investigate the effect of annealing on paramagnetic defect center in P+-implanted C60 films, in order to control and improve the electronic properties of the implanted films towards photovoltaic applications. We have found a reduction in the dangling bond density upon annealing by approximately a one order of magnitude, in the temperature range between 100°C and 700°C, regardless of the annealing media whether vacuum or forming gas (N2/H2). The reduction in spin defect density was ascribed to the decrease in disordered dangling bond as a consequence of the reconstruction of the less stable defect sites. Indeed the modification in the spin density is accompanied with an improvement in the electrical conductivity and band structure of the films. Also, in the annealed carbon films, a correlation was observed among linewidth, relaxation times, and optical gap. In addition, we report about the temperature dependence of the linewidth, signal intensity and the susceptibility of annealed films. The susceptibility follows the Curie-law at sufficiently low temperature, while above 180 K a deviation was observed. The prime novelty of this study is that it is the first EPR study of effects of annealing on defect center in P+- implanted C60 films.

Chromium is commonly found in huge quantities in tannery wastewaters. For this reason, the removal and recovery of the chromium content of tannery wastewaters is crucial for environmental protection and economic reasons. Removal and recovery of chromium were carried out by using low-cost potential adsorbents. For this purpose three types of activated carbon; C1, the waste generated from sugar industry as waste products and the others (C2, C3) are commercial granular activated carbon, were used. The adsorption process and extent of adsorption are dependent on the physical and chemical characteristics of the adsorbent, adsorbate and experimental condition. The effect of pH, particle size and different adsorbent on the adsorption isotherm of Cr(III) was studied in batch system. The sorption data fitted well with Langmuir adsorption model. The efficiencies of activated carbon for the removal of Cr(III) were found to be 98.86, 98.6 and 93 % for C1, C2 and C3, respectively. The order of selectivity is C1>C2>C3 for removal of Cr(III) from tannery wastewater. Carbon "C1" of the highest surface area (520.66 m(2)/g) and calcium content (333.3 mg/l) has the highest adsorptive capacity for removal of Cr(III). The results revealed that the trivalent chromium is significantly adsorbed on activated carbon collected from sugar industry as waste products and the method could be used economically as an efficient technique for removal of Cr(III) and purification of tannery wastewaters.

A number of new crown-formazans with 14 and 15 membered rings have been synthesized, characterized and investigated as selective spectrophotometric chelating agents for lithium. The effect of sodium ion concentration on the background lithium signal was studied. A comparative study for the sensitivity of these new crown-formazans in spectrophotometric determinations was studied and compared with those reported previously. The three new 14- and 15-crown-formazans 4a-c containing the pyridyl N-oxide at the formazyl carbon showed the highest selectivity to lithium determination in the presence of sodium ion.

A number of new crown-formazans with 14 and 15 membered rings have been investigated as selective neutral carriers in cesium ion selective electrodes. Two plasticizers (NPOE and NPBnE) were studied. The new 14-crown-formazan 4a containing the 4-pyridyl N-oxide at the formazyl carbon exhibited the highest selectivity in cesium ion selective electrodes, especially towards the two low selectivity monovalent ions K(+) and NH4(+). Also, membranes containing the plasticizer NPBnE showed better cesium selectivity relative to most ions than those containing NPOE. Membranes containing 4a and variable compositions of plasticizers, potassium tetrakis-(p-chlorophenyl)borate (KTpClPB), and trioctylphosphine oxide (TOPO) were studied in order to prepare an electrode with the optimum cesium selectivity. The highest selectivity for cesium was achieved with the two electrodes designated d and e with membranes containing the ionophore 4a, NPBnE and KTpClPB with and without TOPO. Selectivities are reported relative to sodium, potassium, barium, calcium, ammonium, lithium, cobalt, and magnesium.

Polarographisches Verhalten von 2-Benzoyl-3-thionaphthenon Das polarographische Verhalten des 2-Benzoyl-3-thionaphthenons (I) in wasriger, ethanolischer Pufferlosung zeigt bei Veranderung des pH-Wertes, das die Carbonylgruppe des heterozyklischen Teiles im sauren und neutralen Medium durch einen Zweielektronenprozes reduziert wird. Im stark basischen Bereich ist ein stabilisiertes Enolat die reduzierbare Form der Verbindung I.