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- Author or Editor: J. Liang x
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Abstract
The adsorption behavior of silica gel for Zr, Pu and fission products (Fe, Mo, Nd, etc.) in high-level liquid waste (HLLW) have been studied. The dynamic desorption for Zr and Pu are also investigated. Silica gel is found to have high selectivity for Zr to other elements in HLLW and its adsorption capacity can be enhanced by H2C2O4 elution and multiple reuse. However, the adsorption for Pu(IV) is also found. This may cause spent silica gel to be alpha waste. Further study should be carried out on the adsorption behavior for Pu(IV).
Abstract
Molar heat capacities of acetaminophen were precisely measured with a small sample precision automated adiabatic calorimeter over the temperature range from 80 to 330 K. A solid-solid transition at 149.96 K was found from the C p,m-T curve. The polynomial functions of C p,.m(J K-1 mol-1) vs. T were established on the heat capacity measurements by means of the least square fitting method. Thermal decomposition processes of acetaminophen have been studied by thermogravimetry. And the thermal decomposition kinetics parameters, such as activation energy E, pre-exponential factor A and reaction order n, were calculated by TG-DTG techniques with the Freeman-Carroll method, Kissinger method and Ozawa method. Accordingly the thermal decomposition kinetics equation of acetaminophen is expressed as: dα/dt=2.67107e-89630/RT(1-α)0.23. The process of fusion has been investigated through DSC. The melting point, molar enthalpy and entropy of fusion are to be (441.890.04) K, 26.490.44 kJ mol-1 and 59.801.01 J K-1 mol-1, respectively.
Abstract
A microcalorimetric technique based on the bacterial heat output was applied to evaluate the influence of antibiotics PIP (Piperacillin Sodium) and composite preparation of PIP and SBT (Sulbactam Sodium) on the growth of E. coli DH5α. The power–time curves of the growth metabolism of E. coli DH5α were studied using a TAM Air Isothermal Microcalorimeter at 37C. By analyzing the power–time curves, the parameters such as growth rate constants (k), inhibitory ratio (I), the maximum heat power (P m) and the time of the maximum heat power (t m) were obtained. The results show that different concentrations of antibiotics affect the growth metabolism of E. coli DH5α. The PIP in the concentration range of 0–0.05 g mL–1 has a stimulatory effect on the E. coli DH5α growth, while the PIP of higher concentrations (0.05 –0.25 g mL–1) can inhibit its growth. It seems that the composite preparation composed of PIP and SBT cannot improve the inhibitory effect on E. coli DH5α as compared with the PIP.
Based on the known GA20-oxidase (GA20ox) cDNAs of barley and wheat, oligonucleotide primers were designed to isolate GA20ox genes from genomic DNA of Dasypyrum villosum. A total of 19 clones were obtained. Each of them contained an open reading frame encoding a putative 40-KDa protein of 359 amino acid residues. Twenty-one SNPs and 4 InDels were found and could divide the 19 sequences into 2 classes, designated as DvGA20ox-1 and DvGA20ox-2, respectively. Q-PCR analyses showed that both DvGA20ox-1 and DvGA20ox-2 were in leaf blade, leaf sheath, stem, eustipes, root and developing spike. Similar expression levels were found between DvGA20ox-1 and DvGA20ox-2 in three stages. The total expression levels of DvGA20ox-1 and DvGA20ox-2 presented downtrend in leaf blade and ascend in stem, eustipes and developing spike along with the development of plants, respectively. However, they were firstly increased and then decreased in root from seeding stage to heading stage. These results revealed that the gene expression profile of DvGA20ox-1 and DvGA20ox-2 closely related to the growth and development of D. villosum.
Summary
An HPLC-DAD-ESI-MSn method has been developed for simultaneous quantification of eight major compounds in eight Saussurea species which have long been used as the traditional Tibetan medicines. The method was validated for sensitivity, precision, and accuracy. LODs were from 0.11 to 5.01 μg mL−1, overall intra-day and inter-day variation was less than 2.70%, and overall recovery was over 98.0%. The correlation coefficients (r 2) of the calibration plots were >0.991. This newly established method was successfully used to reveal difference among the chemical profiles and analytes contents of eight Saussurea species collected in Tibet. In addition, by comparison of UV and mass spectra with those of authentic compounds, a total of fifteen peaks were identified. It can be concluded that this is an effective method for quantification and evaluation of the flavonoids and coumarins in the eight species of the genus Saussurea. It can be used as an efficient reference method for development and use of the eight traditional Tibetan medicines by comparing their different characteristics.
Abstract
The effects of Amoxicillin Sodium and Cefuroxime Sodium on the growth of E. coli DH5α were investigated by microcalorimetry. The metabolic power-time curves of E. coli DH5α growth were determined by using a TAM air isothermal microcalorimeter at 37�C. By evaluation of the obtained parameters, such as growth rate constants (k), inhibitory ratio (I), the maximum heat power (P m) and the time of the maximum heat power (t m), one found that the inhibitory activity of Amoxicillin Sodium vs. E. coli DH5α is enhanced with the increasing of the Amoxicillin Sodium concentration, and the Cefuroxime Sodium has a stimulatory effect on the E. coli DH5α growth when the concentration is about 1 μg mL−1. The IC50 for the Amoxicillin Sodium and the Cefuroxime Sodium are 1.6 and 2.0 μg mL−1, respectively, it implicates that the E. coli DH5α is more sensitive to Amoxicillin Sodium than Cefuroxime Sodium.
A high-speed counter-current chromatography (HSCCC) method was established for the isolation and purification of isochlorogenic acid A from Lonicera japonica Thunb. The two-phase solvent system was composed of n-hexane:ethyl acetate: isopropanol:water (2:3:2:5, v/v/v/v). From 150 mg of the ethyl acetate fraction of L. japonica Thunb, 19.65 mg of isochlorogenic acid A was obtained in a one-step HSCCC separation, with a purity of 99.1%, as determined by high-performance liquid chromatography (HPLC). The structure was further identified by ultraviolet (UV), mass spectrometry (MS) and nuclear magnetic resonance (NMR).
Citri Grandis Exocarpium (CGE) is a traditional Chinese medicine with a variety of biological activities. For efficient quality control of CGE, a simple, rapid, and accurate high-performance liquid chromatographic (HPLC) method was developed for simultaneous determination of four main compounds (naringin, rhoifolin, meranzin hydrate, and isoimperatorin) in this herb. These four compounds were separated on a C18 column by gradient elution with methanol and water. The flow rate was 1.0 mL·min−1, and the detection wavelength was 324 nm. The recoveries of the method ranged from 96.32% to 103.71%, and good linear relationships (r 2 > 0.9998) over relative wide concentration ranges were obtained. Then this validated method was successfully applied to the analysis of nine batches of CGE samples.
