Solvent extraction of rhodium, ruthenium and iridium with di(2-ethylhexyl)phosphoric acid (HDEHP) has been investigated. Under the conditions [Cl–1]=0.20M, [(HDEHP)2]=0.30M, pH 4.05, phase contact time 1 minutes, Rh(III) is extracted 90.7%, Ru(III) and Ir(III) 20.0% and 11.5%, respectively, at phase ratio 11. The distribution ratio of rhodium is proportional to [(HDEHP)2]3 for a freshly prepared aqueous phase with low chloride concentration but might drop to [(HDEHP)2]1to2 for an aqueous phase high in chloride concentration and after standing. The spectroscopic studies indicate that the extracted compound of rhodium is Rh(H2O)6–xClx[H(DEHP)2]3–x (x=0, 1, 2).
Solvent extraction of rhodium, ruthenium, and iridium with HDEHP from thioureachloride media was investigated. Under the conditions ([Cl–]=0.50 M, [HDEHP]=1.0M, [SC(NH2)2]=0.50M, pH=4.50, phase contact time 1 min), Rh(III) is extracted 88.3%, Ru(III) and Ir(III) 40.8% and 28.5% respectively at phase ratio 11. The formation of rhodium-thiourea complexes in aqueous solutions, even at 5M chloride concentration, with the possible composition Rh[SC (NH2)2]63+ is confirmed by the observed molar ratio of thiourea to rhodium and UV-spectra.
The calorimetric data of binders containing
pure Portland cement, 20% fly ash, 20% slag and 10% silica fume respectively
are determined at different initial casting temperatures using an adiabatic
calorimeter to measure the adiabatic temperature rising of concrete. The calorimetric
data of binders with different dosages of fly ash at two water binder ratios
are determined, too. Elevation of initial casting temperature decreases the
heat evolution of binder, enhances the heat evolution rate of binder and increases
the heat evolution rate of binder at early age. The dosage of fly ash in concrete
has different effects on the heat evolution of binder with different w/b. At high w/b ratio the
heat evolution of binder decreases when dosage of fly ash increases. At low w/b ratio the
heat evolution of binders increases when dosage of fly ash increases from
0 to 40% of total binder quantity. The heat evolution of binder decreases
after the dosage of fly ash over 40%. An appropriate dosage of fly ash in
binder benefits the performance of concrete at low w/b ratio.
Authors:W. Yan, C. Ma, J. Wu, W. Zhang, and D. Jang
Crystal of the complex Ni2L (ClO4)2 was obtained by reaction of Ni(ClO4)2 and macrocyclic ligand H2L, where L2– is the dinucleating macrocycle with two 2,6-di(aminomethyl)-4-methyl phenolate entities combined by the same two lateral chains, –(CH2)2–NH–(CH2)2–, at the amino nitrogens. The thermal decomposition processes of the title complex were studied in a dynamic atmosphere of dry argon using TG-DTG. The kinetic analysis of the first and second thermal decomposition steps were performed via the TG-DTG curves, and the kinetic parameters were obtained from analysis of the TG-DTG curves with integral and differential methods. The most probable kinetic function was suggested by comparison of the kinetic parameters.
The title compound 3,3-dinitroazetidinium (DNAZ) 3,5-dinitrosalicylate (3,5-DNSA) was prepared and the crystal structure has
been determined by a four-circle X-ray diffractometer. The thermal behavior of the title compound was studied under a non-isothermal
condition by DSC and TG/DTG techniques. The kinetic parameters were obtained from analysis of the TG curves by Kissinger method,
Ozawa method, the differential method and the integral method. The kinetic model function in differential form and the value
of Ea and A of the decomposition reaction of the title compound are f(α)=4α3/4, 130.83 kJ mol−1 and 1013.80s−1, respectively. The critical temperature of thermal explosion of the title compound is 147.55 °C. The values of ΔS≠, ΔH≠ and ΔG≠ of this reaction are −1.35 J mol−1 K−1, 122.42 and 122.97 kJ mol−1, respectively. The specific heat capacity of the title compound was determined with a continuous Cp mode of mircocalorimeter. Using the relationship between Cp and T and the thermal decomposition parameters, the time of the thermal decomposition from initiation to thermal explosion (adiabatic
time-to-explosion) was obtained.
Authors:J. Wang, Z. Yan, Y. Zheng, W. Cao, and Y. Wei
Fructose-bisphosphate aldolase (FBA, EC 18.104.22.168) catalyzes an aldol cleavage of fructose-1, 6-bisphosphate to dihydroxyacetone-phosphate and glyceraldehyde 3-phosphate and a reversible aldol condensation. Three candidate genes with 1077bp coding for fructose-bisphosphate aldolase were cloned and sequenced in wheat, barley and rye. These genes could encode 358 amino acid residues. Sequence analysis indicated that wheat, barley and rye FBA genes were conserved with high identity (94.13%), while maize sequence had a 9bp deletion near the 3’ terminal. According to the alignment of 75 amino acid sequences, conserved domains of the FBAs were detected. These conserved domains might be the important functional sites of the FBAs. The cytoplasmic FBAs of wheat, barley and rye were clustered together, and the cluster was close to maize and rice FBAs. Nine peptides of the FBAs and the last amino acid Tyr (necessary for preference for fructose 1,6-bisphosphate over fructose 1-phosphate) were most conserved in plants, animals and algae. Current findings suggested that the FBAs could be divided into three main subgroups: plant cytoplasmic FBA, plant chloroplastic FBA and animal FBA. These results also indicated that the active and binding sites of FBAs had rare variations during the long-term evolution.
Authors:H.J. Shi, Z.J. Sun, Z.M. Yan, and J.B. Ren
Temperature uniformity and heating rate subjected to radio frequency (RF) heating have major impact on the quality of treated low moisture foods. The objective of this paper was to analyse the influence of electrode distance on the heating behaviour of RF on condition that the sample shape, size, and location between the electrodes were defined. Considering peanut butter (PB) and wheat flour (WF) as sample food, a 3D computer simulation model was developed using COMSOL, which was experimentally validated by a RF machine (27.12 MHz, 6 kW). Specifically, the electrode distances were selected as 84, 89, 93, 99 and 89, 93, 98, 103 (mm) for RF heating of PB and WF, respectively. Results showed that the simulated results and experimental data agreed well; the temperature-time histories of the RF heating of PB and WF were approximate straight lines; both the temperature uniformity index and the heating rate decreased with the increase of the electrode distance; the heating rate had a negative logarithmic linear relationship with the electrode distance, which was independent of the types, geometry shapes and sizes of low moisture foods.
Authors:X. X. Han, X. M. Jiang, Z. G. Cui, J. W. Yan, and J. G. Liu
For obtaining high shale oil yield as well as treating shale char efficiently and in an environmentally friendly way in a new comprehensive utilization system of oil shale, a series of fundamental experiments have been conducted for exploring the effects of retorting factors on shale oil yield and shale char characteristics. Based on these previous studies, in this article, combustion experiments of shale chars obtained under various retorting conditions were performed with a Q5000IR thermogravimetric analyzer and a Leitz II-A heatable stage microscope and the effects of retorting factors were discussed on the combustion characteristics of shale char. Among four studied retorting parameters, retorting temperature and residence time exert very significant influence on the combustion characteristics of shale char. Either elevating the retorting temperature from 430 to 520 °C or lengthening the residence time at a low retorting temperature will largely decrease residual organic matters within shale char, resulting in decreasing mass loss in the low-temperature stage of combustion process of shale char, an elevation of ignition temperature and a shift of ignition mechanism from homogeneous to heterogeneous. One set of retorting condition was also recommended as a reference for designing the comprehensive utilization system of oil shale studied in this work: retort temperature of 460–490 °C, residence time of 20–40 min, particle size of <3 mm, and low heating rate of <10 °C/min.
Authors:W. Xue, A. Gianinetti, Y. Jiang, Z. Zhan, L. Kuang, G. Zhao, J. Yan, and J. Cheng
The cereal endosperm provides nutrients for seedling growth. The effects of seed components in seedling establishments under salt stress are, however, not yet fully explored. In this study, 60 barley recombinant inbred lines derived from Lewis × Karl cross were grown in four different environments, and the seed contents of starch, total soluble protein, phytate, total phenolics, total flavonoids and total inorganic phosphorus were determined in the harvested grains. Seeds of each line from the four environments were also assayed for seedling growth under saline treatments from 0 to 400 mM NaCl. Root and shoot lengths after 7 days decreased with increasing salt concentration. Correlations between seed components and either root or shoot length were established across the four seed sources. ANOVA showed a significant environment/source effect for both seed components and seedling growth, although the latter was less affected by the seed-production environment. Modeling seedling length across multiple salinities for each seed source showed that the environment with the most saline-tolerant root-growth curve was that associated the highest seed phosphorus content. Correlations between seed components and seedling growth traits highlighted phytate and total inorganic phosphorus as key components for seedling growth under moderate salinities. Seed phytate contents benefited seedling growth, even at high salinities, suggesting an additional role for this seed component under stressful growth conditions, possibly linked to its potential function as an osmolyte source.
Authors:Q. Chen, M. Cao, W. Xiang, Q. Sun, J. Zhang, R. Hou, Z. Yan, Z. Yang, J. Liu, and J. Zhao
The forward and reverse cDNA subtractive libraries before and after the toxic effect of α-amanitin were constructed by suppression subtractive hybridization and randomly selected clones from each subtractive library were screened by PCR and dot blot hybridization. A total of 85 genes with altered expression were finally identified, with 41 genes from the forward library and 44 from the reverse library. Subsequently, the antagonistic effects of candidate traditional Chinese medicines were evaluated based on the genetic transcription levels of the genes with significant altered expression, including Catnβ, Flt3-L, IL-7r and Rpo2-4. The results indicated that
(L.) Gaert and
had significant down-regulated effects on the transcription level of Catnβ that was up-regulated by α-amanitin, and the two herbs also up-regulated the transcription levels of Flt3-L and Rpo2-4.
(L.) had significant up-regulated effects on the IL-7r that was down-regulated by α-amanitin. These preliminary studies suggested that
were effective antagonists against the toxicity of α-amanitin.