Among the progenies of crossing
Triticum turgidum — Haynaldia villosa
amphiploid with synthetic hexaploid wheat
(T. carthlicum / Aegilops tauschii)
Am3, two lines (SN030713 and SN05078), with good resistance to stripe rust and powdery mildew, were developed. Cytological studies demonstrated that SN030713 contained 42 chromosomes and formed 21 bivalents at meiotic metaphase I. SN05078 contained 28 chromosomes and formed 14 bivalents. Genomic
hybridization analysis using
V genomic DNA as the probe showed SN030713 and SN05078 had no large
chromosome fragments. PCR analysis with
specific primer pHv29 showed that
genetic materials were introgressed in these two lines. SSR analysis indicated that the genomic composition of SN030713 was 2n = 6x = 42 (AABBDD), and SN05078 was 2n = 4x = 28 (AABB). Introgressed
genetic materials in SN05078 were also detected.
Thermal decomposition of N,N′-diphenylguanidine (DPG) was investigated by simultaneous TG/DSC-FTIR techniques under nonisothermal conditions. Online FTIR measurements illustrate that aniline is a major product of DPG decomposition. The observation that the activation energy depends on the extent of conversion indicates that the DPG decomposition kinetics features multiple processes. The initial elimination of aniline from DPG involves two pathways because of the isomerization of DPG. Mass spectrometry and thin film chromatography suggest that there are two major intermediate products with the major one of C21N3H17. The most probable kinetic model deduced through multivariate nonlinear regression method agrees well with the experimental data with a correlation coefficient of 0.9998. The temperature-independent function of conversion f(α), activation energy E and the pre-exponential factor A of DPG decomposition was also established through model-fitting method in this research.
Authors:L. Li, X. Wang, J. Shen, L. Zhou, and T. Zhang
Adsorption microcalorimetry has been employed to study the interaction of ethylene with the reduced and oxidized Pt-Ag/SiO2catalysts with different Ag contents to elucidate the modified effect of Ag towards the hydrocarbon processing on platinum
catalysts. In addition, microcalorimetric adsorption of H2, O2, CO and FTIR of CO adsorption were conducted to investigate the influence of Ag on the surface structure of Pt catalyst.
It is found from the microcalorimetric results of H2and O2adsorption that the addition of Ag to Pt/SiO2leads to the enrichment of Ag on the catalyst surface which decreases the size of Pt surface ensembles of Pt-Ag/SiO2catalysts. The microcalorimetry and FTIR of CO adsorption indicates that there still exist sites for linear and bridged CO
adsorption on the surface of platinum catalysts simultaneously although Ag was incorporated into Pt/SiO2. The ethylene microcalorimetric results show that the decrease of ensemble size of Pt surface sites suppresses the formation
of dissociative species (ethylidyne) upon the chemisorption of C2H4on Pt-Ag/SiO2. The differential heat vs. uptake plots for C2H4adsorption on the oxygen-preadsorbed Pt/SiO2and Pt-Ag/SiO2catalysts suggest that the incorporation of Ag to Pt/SiO2could decrease the ability for the oxidation of C2H4.
A new ecomaterial, zirconyl molybdopyrophosphate (ZMPP), was prepared by a coprecipitation method. The removal of Cs+ and Sr2+ ions from simulated strong acid HLLW using the ion exchange process on ZMPP had been investigated. It showed that there are more than 90% Cs+ and Sr2+ removed from the simulated HLLW on ZMPP despite the presence of other metal ions, such as Na+, Al3+, Fe3+, etc. in excess. Then ZMPP may likely be a selective ion exchanger for the removal of 137Cs and 90Sr directly from strong acid HLLW.
Authors:Z. Chen, F. Xie, X. Wang, Y. Chang, and Z. Zhang
A method of efficiency calibration for the measurement of 88Kr and 138Xe by HPGe γ-spectrometer is proposed in the present paper. The question for the efficient calibration is, how to achieve
homogeneous sources of 88Kr-88Rb and 138Xe-138Cs. The fission product gases were obtained by irradiating a precisely measured amount of U3O8 (90% 235U) filled in a quartz glass ampoule. Source cell was first filled up with stearic acid, and then the fission product gases
were charged into it. Xenon and krypton are not adsorbed on stearic acid, therefore, homogeneous sources of 88Kr-88Rb and 138Xe-138Cs can be prepared. The results of the experiment demonstrate that the method is feasible and successful.
The effects of bentonite density and fulvic acid on the sorption and diffusion of 90Sr2+in compacted bentonite were investigated by using a capillary method. The experiments were carried out at pH 7.0±0.1 in the
presence of 0.01M NaClO4. The results suggest that the sorption and diffusion of 90Sr2+in compacted bentonite decreases with increasing the density of compacted bentonite. The presence of FA enhances the sorption
of Sr2+, but reduces the diffusion of Sr2+in compacted bentonite. The porosity of the compacted bentonite plays an important role in the sorption and diffusion behavior
of 90Sr2+. Using the calculated effective diffusion coefficients the long-term relative concentration distribution of strontium was
evaluated in compacted bentonite.
On dehydration of La[Co(CN)6]5H2O, the color of the complex, changes from white to pale blue at around 230C. Heating the pale blue specimen, the color changes
to deep blue at around 290C. This deep blue specimen is easily rehydrated to a pink one. As reported previously, in the pale
blue specimen, Co3+ ions are situated in the center of the D4h crystal field formed by six CN- ions.
The deep blue specimen is due to the presence of [Co(CN)4]2- ions in which Co2+ was situated in a Td coordination field formed by four CN- ions and the Co-C bond length is 1.67 Ĺ. The pink species corresponded to trans-[Co(CN)4(H2O)2]2- and the bond lengths of Co-C and Co-O are 1.89 and 1.85 Ĺ, respectively.
The Raman spectra of the complex observed at 25C displays two bands at 2157 and 2176 cm-1 associated with the vibration of C-N bond, and the band of 2157 cm-1 was split into two bands, 2150 and 2156 cm-1, at around 100C. When the complex was heated to around 230C, three new bands were observed at 2103, 2116 and 2141 cm-1.
The bands of 2103 and 2116 cm-1 were assigned to the stretching vibration of C=N bonding to Co2+. The band of 2141 cm-1 was assigned to the stretching vibration of the inverted CN- as follows: Co-C=N-La→Co-N=C-La. The activation energy for the inversion of CN- was estimated as 67 kJ mol-1.
N,N,N',N'-Tetrabutyladipicamide (TBAA) was used for the extraction of nitric acid and uranyl(II) ion from nitric acid media
into toluene. The effects of nitric acid, uranyl(II) ion, and extractant concentration, temperature and back extraction on
the distribution coefficient of uranyl(II) ion have been studied. The main adduct of TBAA and HNO3 is TBAA·HNO3 in 1.0 mol/l nitric acid solution. The 1:2:2 complex of uranyl(II) ion, nitrate ion and TBAA as extracted species is further
confirmed by IR spectra of the extraction of uranyl(II) ion with TBAA. The values of the thermodynamic parameters have also
Authors:D. Sims, W. Andrews, X. Wang, and K. Creber
In 1951, unsaturated prairie soil was contaminated with fission products and actinides. Fifty years later, in 2001, soil samples
were collected from the contaminated site. This paper describes the techniques used to analyze these samples, including gamma-spectroscopy
(GS) for 137Cs, neutron activation analysis (NAA/GS) for 238U, liquid scintillation counting (LSC) for 90Sr and inductively coupled plasma mass spectroscopy (ICP-MS) for 238U and 113mCd. As expected, ICP-MS was found to have the lowest detection level, while the techniques were ranked in order of increasing
uncertainty as GS, NAA/GS, ICP-MS and LSC.
Eight cultivars of dry-land wheat (Triticum aestivum L.) historically planted in Shaanxi Province, China, were grown in plots with irrigation and drought treatments during the growing seasons of 2011–2014, so as to characterize the differences in the rate and duration of the grain-filling stage among cultivars. The experimental results showed no obvious change among cultivars with respect to the duration of the grain-filling stage and no significant correlation between duration and grain weight. The filling rates of all three phases (lag, linear, and mature periods) showed significant differences among cultivars and had a greater effect on the grain weight than the duration of the filling stage, even though drought decreased the filling rate in the linear and mature periods. A lower filling rate led to a lighter grain weight in inferior grains than in superior grains. For the superior and inferior grains in the central spikelets, modern cultivars possess faster filling rates, especially in the lag and linear periods, whereas for the whole spike, no significant trend with cultivar replacement was observed. Faster filling rates with stable filling durations will be beneficial in obtaining additional yield increases.