Authors:Z.L. Li, H.Y. Li, G. Chen, X.J. Liu, C.L. Kou, S.Z. Ning, Z.W. Yuan, M. Hao, D.C. Liu, and L.Q. Zhang
Seven Glu-A1m allelic variants of the Glu-A1mx genes in Triticum monococcum ssp. monococcum, designated as 1Ax2.1a, 1Ax2.1b, 1Ax2.1c, 1Ax2.1d, 1Ax2.1e, 1Ax2.1f, and 1Ax2.1g were characterized. Their authenticity was confirmed by successful expression of the coding regions in E. coli, and except for the 1Ax2.1a with the presence of internal stop codons at position of 313 aa, all correspond to the subunit in seeds. However, all the active six genes had a same DNA size although their encoding subunits showed different molecular weight. Our study indicated that amino acid residue substitutions rather than previously frequently reported insertions/deletions played an important role on the subunit evolution of these Glu-A1mx alleles. Since variation in the Glu-A1x locus in common wheat is rare, these novel genes at the Glu-A1mx can be used as candidate genes for further wheat quality improvement.
Authors:Y. Y. Di, Z. C. Tan, L. W. Li, S. L. Gao, and L. X. Sun
Low-temperature heat capacities of a solid complex Zn(Val)SO4·H2O(s) were measured by a precision automated adiabatic calorimeter over the temperature range between 78 and 373 K. The initial dehydration temperature of the coordination compound was determined to be, TD=327.05 K, by analysis of the heat-capacity curve. The experimental values of molar heat capacities were fitted to a polynomial equation of heat capacities (Cp,m) with the reduced temperatures (x), [x=f (T)], by least square method. The polynomial fitted values of the molar heat capacities and fundamental thermodynamic functions of the complex relative to the standard reference temperature 298.15 K were given with the interval of 5 K.
Enthalpies of dissolution of the [ZnSO4·7H2O(s)+Val(s)] (ΔsolHm,l0) and the Zn(Val)SO4·H2O(s) (ΔsolHm,20) in 100.00 mL of 2 mol dm−3 HCl(aq) at T=298.15 K were determined to be, ΔsolHm,l0=(94.588±0.025) kJ mol−1 and ΔsolHm,20=–(46.118±0.055) kJ mol−1, by means of a homemade isoperibol solution–reaction calorimeter. The standard molar enthalpy of formation of the compound was determined as: ΔfHm0 (Zn(Val)SO4·H2O(s), 298.15 K)=–(1850.97±1.92) kJ mol−1, from the enthalpies of dissolution and other auxiliary thermodynamic data through a Hess thermochemical cycle. Furthermore, the reliability of the Hess thermochemical cycle was verified by comparing UV/Vis spectra and the refractive indexes of solution A (from dissolution of the [ZnSO4·7H2O(s)+Val(s)] mixture in 2 mol dm−3 hydrochloric acid) and solution A’ (from dissolution of the complex Zn(Val)SO4·H2O(s) in 2 mol dm−3 hydrochloric acid).
Authors:S. Wang, L. Xiao, Y. Li, Z. Fang, G. Qiu, and J. Li
A dual cell system was used to study the electrogenerative leaching sphalerite-MnO2 under the conditions of presence and absence of Acidithiobacillus ferrooxidans (A. ferrooxidans). The polarization of anode and cathode, and the relationship between the electric quantity (Q) and some factors, such as the dissolved Zn2+, Fe2+, the time in the bio-electro-generating simultaneous leaching (BEGSL) and electro-generating simultaneous leaching (EGSL),
The results show that the dissolved Zn2+ in the presence of A. ferrooxidans is nearly 60% higher than that in the absence of A. ferrooxidans; the electrogenerative quantity in the former is about 134% more than that in the latter. A three-electrode system was applied
to study anodic and cathodic self-corrosion current, which was inappreciable compared with the galvanic current between sphalerite
and MnO2. The accumulated sulfur on the surface of sulfides produced in the electrogenerative leaching process could be oxidized in
the presence of A. ferrooxidans, and the ratio of biological electric quantity reached to 31.72% in 72 h.
Authors:Z. Zhang, T. Cui, J. Zhang, H. Xiong, G. Li, L. Sun, F. Xu, Z. Cao, F. Li, and J. Zhao
The molar heat capacities of the room temperature ionic liquid 1-butyl-3-methylimidazolium hexafluoroborate (BMIPF6) were measured by an adiabatic calorimeter in temperature range from 80 to 390 K. The dependence of the molar heat capacity
on temperature is given as a function of the reduced temperature (X) by polynomial equations, CP,m (J K−1 mol−1) = 204.75 + 81.421X − 23.828 X2 + 12.044X3 + 2.5442X4 [X = (T − 132.5)/52.5] for the solid phase (80–185 K), CP,m (J K−1 mol−1) = 368.99 + 2.4199X + 1.0027X2 + 0.43395X3 [X = (T − 230)/35] for the glass state (195 − 265 K), and CP,m (J K−1 mol−1) = 415.01 + 21.992X − 0.24656X2 + 0.57770X3 [X = (T − 337.5)/52.5] for the liquid phase (285–390 K), respectively. According to the polynomial equations and thermodynamic relationship,
the values of thermodynamic function of the BMIPF6 relative to 298.15 K were calculated in temperature range from 80 to 390 K with an interval of 5 K. The glass transition
of BMIPF6 was measured to be 190.41 K, the enthalpy and entropy of the glass transition were determined to be ΔHg = 2.853 kJ mol−1 and ΔSg = 14.98 J K−1 mol−1, respectively. The results showed that the milting point of the BMIPF6 is 281.83 K, the enthalpy and entropy of phase transition were calculated to be ΔHm = 20.67 kJ mol−1 and ΔSm = 73.34 J K−1 mol−1.
Authors:X.-C. Lv, Z.-C. Tan, Z.-A. Li, Y.-S. Li, J. Xing, Q. Shi, and L.-X. Sun
The (R)-BINOL-menthyl dicarbonates,
one of the most important compounds in catalytic asymmetric synthesis, was
synthesized by a convenient method. The molar heat capacities Cp,m
of the compound were measured over the temperature range from 80 to 378 K
with a small sample automated adiabatic calorimeter. Thermodynamic functions
[HT–H298.15] and [ST–S298.15] were derived in the
above temperature range with a temperature interval of 5 K. The thermal stability
of the substance was investigated by differential scanning calorimeter (DSC)
and a thermogravimetric (TG) technique.
Authors:C. Liu, S. Li, X. Wang, Z. Wang, H. Wang, R. Li, C. Xin, B. Li, L. Jiang, and C. Jia
The migration of 99Tc in unsaturated Chinese loess was investigated in-situ with a tracer method. Quartz containing 3H (HTO) and 99Tc (99TcO4-) was introduced into the bottom of an experimental pit which was then backfilled at the field test site. Then core soil samples were taken and cut vertically into 1 cm long slices. The slice samples were analyzed by liquid scintillation techniques in the laboratory. The results indicate that the migration pattern of 99Tc was quite similar to that of 3H and the vertical diffusion coefficients of 99Tc and 3H were calculated as (4.7±0.4).10-2 cm2/d and (7.8±0.4).10-2 cm2/d, respectively.
Authors:Z. Wang, M. Lv, D. Li, Z. Zhou, L. Zhang, and W. Yang
A new HPLC method has been established for determination of 3-monoiodotyrosine (MIT), 3,5-diiodotyrosine (DIT), 3,5-diiodothyronine (T2), 3,3′,5-triiodothyronine (T3), 3,3′,5′-triiodothyronine (rT3), and thyroxine (T4) produced by hydrolysis of iodinated casein with barium hydroxide. The hydrolytic stability of each analyte was evaluated. Iodinated casein was hydrolyzed with saturated barium hydroxide solution for 16 h at 110°C and the barium ions were then removed as barium sulfate. Reversed-phase HPLC was performed on a 2.1 mm × 150 mm, 5 μm particle, C18 column with a mixture of acetonitrile and 0.1% (v/v) formic acid as mobile phase at a flow rate of 0.2 mL min–1. Acetonitrile was maintained at 5% (v/v) for 5 min and then increased linearly to 50% (v/v) within 35 min. All analytes were quantified by measuring the absorbance at 280 nm. Validation data indicated the method was linear, with regression coefficients (R2) > 0.998, in the concentration ranges investigated. Sensitivity was adequate—limits of detection (LOD) were 0.04–0.38 μg mL–1 and limits of quantification (LOQ) were 0.05–0.38 μg mL–1. Accuracy and precision were acceptable — for all the analytes recovery was 82.0–93.0% and repeatability, as relative standard deviation, was 1.0–3.0%. Hydrolytic stability tests indicated MIT and DIT are much more stable than the other analytes. rT3 was not released directly from iodinated casein but was formed by deiodination of T4 during hydrolysis. The method could be used to identify iodinated casein, to evaluate its activity and quality, and for supervision and regulation of feed additives.
Authors:Z. Zhang, F. Li, L. Xu, N. Liu, H. Xiao, and Z. Chai
Chemical behavior of lanthanum in root tips excized from wheat seedlings growing at both promotional and inhibitory levels of LaCl3 in culture solutions was investigated by a sequential leaching procedure combined with instrumental neutron activation analysis. The results indicate that most of La exists in non-exchangeable species and the binding of La3+ to the root tips is extremely stable. The root tips during growing at the inhibitory level of LaCl3 absorb much more La than those at the promotional level. However, the La proportion in each fraction is similar for both groups.