Authors:Viswanathan Suraja, Zahira Yaakob, Narayanan Binitha, Ali Ebshish, and Koodathil Ranjana
surface [ 3 – 18 ]. Even though much effort has been made to seek the best capping agents, many organic passivators such as thiophenol [ 19 ], thiourea [ 20 ] and mercapto acetate [ 21 ] and so on, are toxic, which can be a potential pollutant. Use of more
Authors:Jintao Wan, Hong Fan, Bo-Geng Li, Cun-Jin Xu, and Zhi-Yang Bu
Synthesis of PAN4
Acrylonitrile-capped poly(propylene imine) dendrimer was synthesized via the single-molecule Michael addition between primary amine functionalities and double bonds of acrylonitrile under ambient conditions to afford an amine
Selenium intake of the human population is very distinct and depends on the Se-content of consumed food. The higher intake of selenium can decrease the risk of many health problems in human and animal organisms. The main task of this work was to obtain new comparable data on Se content of Agaricus bisporus mushroom. The selenium content of different, common varieties of Agaricus bisporus and of its three cultivation's flushes was determined. The Se content of varieties varies between 0.46 mg kg-1 d.m. and 5.63 mg kg-1 d.m., and the average content is 2.82 (± 1.48) mg kg-1 d.m. The caps of fruit bodies have always higher selenium content than the stipe. The average cap/stipe selenium ratio is 1.29. The changes of Se concentration during the cultivation (in cultivation's flushes) are not significant. The most important cultivated mushroom species of the world (Agaricus bisporus) has, in addition to other more valuable properties, a remarkable Se-content. Consumption of fruit bodies can improve the Se supply of human organism, i.e. some health risks can be decreased.
Authors:Paola Fini, N. Depalo, R. Comparelli, M. Curri, M. Striccoli, M. Castagnolo, and A. Agostiano
The dispersibility of organic capped nanocrystals (NCs) in diverse solvents is one of the key factor of the success of such
a class of nanostructured materials. In this work the α-cyclodextrins, mediated phase transfer has been considered as an effective
procedure to direct the NC transfer from the organic solvent to water. The effect of the original organic solvent, namely
hexane and chloroform, and of the ligand molecule coordinating CdS nanocrystal surface has been investigated by optical (UV-Vis,
Photoluminescence, FTIR, Dynamic Light Scattering) and calorimetric techniques.
The calorimetric investigation has been carried out by performing dilution experiments and the correlation between thermal
effects and dilution ratio has been evaluated using the McMillan approach. The obtained results have provided relevant insight
on the parameters driving the phase transfer process and on the NC mutual interaction, thus resulting valuable on the effectiveness
of the phase transfer procedure.
For the enhancement of thermal stability of poly(p-dioxanone) (PPDO), the isocyanate end-capping reagent was prepared by treatment of toluene-2,4-diisocyanate with an equivalent
of 1-hexyl alcohol. The end-capping reagent and the end-capping PPDO with an inherent viscosity of 0.26 dL g−1 were characterized by FTIR and 1H-NMR. Thermal stability of the end-capping PPDO with an inherent viscosity of 0.92 dL g−1 was investigated isothermally and non-isothermally under air atmosphere using thermogravimetry. It has been shown that the
addition of the prepared isocyanate can enhance significantly the thermal stability of PPDO. The activation energies for non-isothermal
degradation estimated by Kissinger method and Friedman method are 91, 81 kJ mol−1 for as-prepared PPDO, and 160, 149 kJ mol−1 for the end-capping PPDO, respectively. The activation energy increases by about 70 kJ mol−1 through the end-capping.
Authors:Fengyan Ding, Dongyuan Wang, Shixia Song, and Shuying Xu
Two new types of reversed-phase sintered plate have been prepared used in planar electrochromatography (PEC). One was bonded with phenyl, instead of octadecyl, without end-capping or with different amounts of end-capping and the other was bonded with octadecyl and then end-capped with phenyl instead of methyl. Both worked well with mobile phases containing no buffer salts, and high potential could be used with low Joule heating. Four dyes were used as samples to examine the characteristics of these two types of plate in planar electrochromatography. The former was unsatisfactory but the latter gave satisfactory results. Our preliminary work revealed that suitable bonding of octadecyl was from 0.03 to 0.06 whereas suitable bonding of phenyl for end-capping was from 0.005 to 0.02, which was readily achieved.
Authors:Y. Li, N. Obando, F. Tschen, and R. J. Morgan
Thermal analysis of phenylethynyl end-capped imide oligomer AFR-PEPA-4
was performed to characterize cure reaction, thermal stabilities and semicrystalline
behavior of AFR-PEPA-4 oligomer and its cured polyimide. Cured AFR-PEPA-4
polyimide showed high Tgs
up to 418C. Both AFR-PEPA-4 oligomer and polyimide exhibit excellent
thermal stabilities comparable to PETI-5 polyimides. AFR-PEPA-4 imide oligomer
has a Tm of 330C
and exhibits spherulite crystalline morphology in the film. The crystallinity
in AFR-PEPA-4 films could not be regenerated under any annealing conditions
after the initial melt.
In PI466495, a powdery mildew resistance source of wild barley (
), one gene conferring powdery mildew resistance was identified in the
locus. In this paper, the
gene sequence was used as source for the development of a cleaved amplified polymorphic sequence (CAPS) marker. Co-segregation between this marker and powdery mildew resistance was analysed by specific DNA fragments associated with each allele of the gene using 286 F
plants derived from a cross between winter barley (
L.) variety ‘Tiffany’ and PI466495. For the co-dominant marker
, three fragments, 370 bp, 82 bp and 59 bp in size, were amplified from F
plants exhibiting resistance reaction types 0 and 0–1 to powdery mildew; whereas two fragments, 429 bp and 82 bp in size, were amplified in susceptible plants. Simple procedures based on polymerase chain reaction and restriction enzyme digestion allowed for identifying the plants susceptible to powdery mildew (
) and plants homozygous or heterozygous for the resistance allele. The
marker was positioned 0.85 cM to the resistance gene and the efficiency of marker-assisted selection (MAS), evaluated as the probability of crossing-over between the marker and the targeted gene, was 99%. The CAPS marker
is a valuable candidate for MAS and gene transfer into barley varieties susceptible to powdery mildew.