Authors:J. Wang, Q. Li, M. Wu, G. Xu, Ch. Li, B. Bao, W. Zheng, H. He, and Sh. Zhang
N,N-dimethylhydroxylamine (DMHA) is a novel salt-free reducing reagent used in the separation U from Pu and Np in the reprocessing
of power spent fuel. This paper reports on the radiolysis of aqueous DMHA solution and its radiolytic liquid organics. Results
show that the main organics in irradiated DMHA solution are N-methyl hydroxylamine, formaldehyde and formic acid. The analysis
of DMHA and N-methyl hydroxylamine were performed by gas chromatography, and that of formaldehyde was performed by ultraviolet–visible
spectrophotometry. The analysis of formic acid was performed by ion chromatography. For 0.1–0.5 mol L−1 DMHA irradiated to 5–25 kGy, the residual DMHA concentration is (0.07–0.47) mol L−1, the degradation rate of DMHA at 25 kGy is 10.1–30.1%. The concentrations of N-methylhydroxylamine, formaldehyde and formic acid are (8.25–19.36) × 10−3, (4.20–36.36) × 10−3 and (1.35–10.9) × 10−4 mol L−1, respectively. The residual DMHA concentration decreases with the increasing dose. The concentrations of N-methylhydroxylamine and formaldehyde increase with the dose and initial DMHA concentration, and that of formic acid increases
with the dose, but the relationship between the concentration of formic acid and initial DMHA concentration is not obvious.
Authors:H. Cross, M. Li, B. Petrich, E. Murphy, Y. Wang, and Charles Steenbergen
The p38 MAP kinases are stress-activated MAP kinases whose induction is often associated with the onset of heart failure. This study investigated the role of p38 MAP kinase isoforms in the regulation of myocardial contractility and ischemia/reperfusion injury using mice with cardiac-specific expression of kinase dead (dominant negative) mutants of p38α (p38αdn) or p38β (p38βdn). Hearts were subjected to 20 min ischemia and 40 min reperfusion. Immunofluorescence staining for p38αdn and p38βdn protein was performed on neonatal cardiomyocytes infected with adenovirus expressing flag-tagged p38αdn and p38βdn protein. Basal contractile function was increased in both p38αdn and p38βdn hearts compared to WT. Ischemic injury was increased in p38βdn vs. WT hearts, as indicated by lower posti-schemic recoveries of contractile function and ATP. However, despite a similar increase in contractility, ischemic injury was not increased in p38αdn vs. WT hearts. Immunohistological analysis of cardiomyocytes with comparable levels of protein overexpression show that p38αdn and p38βdn proteins were co-localized with sarcomeric α-actinin, however, p38αdn was detected in the nucleus while p38βdn was exclusively detected in the cytosol. In summary, attenuated p38 activity led to increased myocardial contractility; specific isoforms of p38 and their sub-cellular localization may have different roles in modulating ischemic injury.
Authors:Y. Li, K. Zhou, M. Jiang, B. Zhang, M. Aslam, and H. Zou
Numerous studies showed that lipid transfer proteins (LTPs) play important roles in flower, development, cuticular wax deposition and pathogen responses; however, their roles in abiotic stresses are relatively less reported. This study characterized the function of a maize LTP gene (ZmLTP3) during drought stress. ZmLTP3 gene was transferred into maize inbred line Jing2416; subsequently the glyphosate and drought tolerance of the over-expression (OE) lines were analyzed. Analysis showed that OE lines could significantly enhance drought tolerance. Transgenic maize lines OE6, OE7 and OE8 showed lower cell membrane damage, higher chlorophyll contents, higher protective enzymes activities, better growth and development under drought condition. The results strongly indicated that overexpression of ZmLTP3 could increase drought tolerances in maize.
Authors:B. Patra, S. Bera, S. Molchanoff, Y. Wang, J. Yang, and C. Li
We described the structure of two different morphological gall types, subglobular and fusiform in Ephedra distachya. The gall midge, Xerephedromyia ustjurtensis Fedotova (Diptera: Cecidomyiidae) induces both types of gall formation. Galls are persistent resinous stem swellings usually subglobular and rarely fusiform in shape. Mature galls are solid, hard, indehiscent woody structure with many circular exit holes on their surface. Galls are anatomically similar, but different from the unaffected stems. The mean number of larval cavities varied significantly between subglobular and fusiform galls, while variation of diameter of the larval cavities was not significant between the gall morphotypes. We documented significant (p < 0.05) variation in total gall densities between sexes of Ephedra distachya, where male plants (mean = 0.89 ± 0.15) supporting higher gall densities than females (mean = 0.36±0.04). Total gall densities varied significantly (p < 0.05) among three sample populations of E. distachya and exhibited an increasing trend from mesic to xeric sites along an altitudinal gradient. Gall size also varied between plant sexes and among sites.
Authors:V. Nazarov, V. Chinaeva, M. Frontasyeva, S. Parry, B. Bennet, Chen Pal, and Li Zu
The present paper based on experimental results contains discussions and suggestions on the possible use of fine-powder Al2O3 and SiO2 with their original content of microimpurities of up to 40 elements, as multielement standards for neutron activation analysis. For example, activation analysis of As, Au, Ba, Cr, Cs, Fe, Ga, K, Ni, Sb, Sc, Se, Sr, Ta, Th, Ti, U, W, Zn, Zr and the REE La, Ce, Nd, Sm, Eu, Tb, Tm, Yb contained in SiO2 powder off MERCK reagents showed their concentrations to be 0.1 to 5% of those in IAEA standard SL-1. In Al2O3 this level is even lower, approximately 10 times and more for the majority of the above-mentioned elements. As Al2O3 and SiO2 are good sorbents for the majority of elements, additional introduction of some elements may allow more methods of analysis. The homogeneity of Al2O3 and SiO2 samples both in the original state and after introduction of some elements was determined by neutron activation analysis, and the SD did not exceed 1% for an Al2O3 sample weight of 0.1 g, and 2% for SiO2.
Authors:E. Sabbioni, M. Bonardi, G. Tanet, Li Da-Kang, M. Gallorini, B. Weckermann, and M. Castiglioni
No-carrier-added48V at 37 Mbq (mCi) levels was produced at the JRC-Ispra cyclotron by (, n) reactions on a scandium target and used to label environmental and physiological levels of vanadium for metallobiochemical investigations. The radiochemical separation of48V from Sc is very simple and rapid and involves a single chromatographic step after fast dissolution of the bombarded target. The yield of the separation and the radioisotopic purity of the separated48V were nearly 100% A summary of the main results concerning different metabolic investigations on rats including absorption, retention, transfer of48V from mothers to newborns, binding with enzymes as well as uptake by cell culture system is reported.
Authors:J. Xing, Z. Tan, Q. Shi, B. Tong, S. Wang, and Y. Li
The low-temperature heat capacities of 1-hexadecanol have been measured with an automatic adiabatic calorimeter over the temperature
range from 80 to 370 K. A solid-liquid phase transition was observed at Tm=322.225±0.002 K and the molar enthalpy and entropy of fusion were determined to be 57.743±0.008 kJ mol−1 and 179.19±0.04 J K−1 mol−1, respectively. The purity, the real melting point (T1) and the ideal melting point without any impurity or absolutely purity (T0) of the sample under investigation were determined to be 99.162 mol%, 322.21 and 322.34 K, respectively, by fractional melting
method. According to the polynomial equation of heat capacity and thermodynamic relationship, the thermodynamic functions
of the compound relative to the reference temperature 298.15 K were calculated in the temperature ranges of 80 to 370 K with
an interval of 5 K. In addition, further researches of thermal properties for this compound were carried out by means of TG/DTG.
Authors:M. Lu, B. Wang, Zh. Li, Y. Fei, L. Wei, and Sh. Gao
Antifreeze protein (AFP) can lower the freezing point by inhibiting the growth of ice crystals. In this article, the thermal
hysteresis activity (THA) of a plant AFP was measured with differential scanning calorimetry (DSC). As is shown, when the
amount of ice in the sample was less than 5% THA of this AFP reached as high as 0.35°C. The secondary structure of this AFP
was studied with circular dichroism (CD). The CD spectrum from 195to 240 nm indicated a well-defined secondary structure consisting
11% α-helix, 34%antiparallel β-sheet and 55% random coil.
Authors:J.-J. Zhang, R.-F. Wang, J.-B. Li, H.-M. Liu, and H.-F. Yang
The thermal decomposition of Eu2(BA)6(bipy)2 (BA=C2H5N–2, benzoate; bipy=C10H8N2, 2,2'-bipyridine)and its kinetics were studied under the non-isothermal condition by TG-DTG, IR and SEM methods. The kinetic
parameters were obtained from analysis of the TG-DTG curves by the Achar method, the Madhusudanan-Krishnan-Ninan (MKN) method,
the Ozawa method and the Kissinger method. The most probable mechanism function was suggested by comparing the kinetic parameters.
The kinetic equation for the first stage can be expressed as: dα/dt=Aexp(–E/RT)3(1–α)2/3.
Authors:J. Song, R. Hu, B. Kang, Y. Lei, F. Li, and K. Yu
[Cd(NTO)4Cd(H2O)6]4H2O was prepared by mixing the aqueous solution of 3-nitro-1,2,4-triazol-5-one and cadmium carbonate in excess. The single crystal
structure was determined by a four-circle X-ray diffractometer. The crystal is monoclinic, space group C2/c with crystal parameters
of a=2.1229(3) nm, b=0.6261(8) nm, c=2.1165(3) nm, β=90.602(7), V=2.977(6) nm3, Z=4, Dc=2.055 gcm−3, μ=15.45 cm−1, F(000)=1824, λ(MoKα)=0.071073 nm. The final R is 0.0282. Based on the results of thermal analysis, the thermal decomposition mechanism of [Cd(NTO)4Cd(H2O)6]4H2O was derived. From measurements of the enthalpy of solution of [Cd(NTO)4Cd(H2O)6]4H2O in water at 298.15 K, the standard enthalpy of formation, lattice energy, lattice enthalpy and standard enthalpy of dehydration
have been determined as -(1747.84.8), -2394, -2414 and 313.6 kJ mol−1 respectively.