Authors:Zheng Fang, Shaofen Wang and Zhenghua Zhang
An experiment was done on electrochemical–calorimetry to identify the Peltier heats of the ferro-ferricyanide reversible electrode reaction over the concentration range of 0.075–0.3 mol dm−3 at 298.15 K. A new approach has been developed to obtain the standard potential of this electrode, which was identified as (+0.3580 ± 0.0030) volt at 298.15 K and compared with previously reported values. An equation derived from the approach is also applied to several standard couples, such as Fe(CN)6−3/Fe(CN)6−4, H+/H2, Cu2+/Cu, Cl−/Hg2Cl2,Hg, Fe3+/Fe2+, and Cl−/Cl2 to determine their respective reaction heats with satisfying results.
A method has been investigated for high-speed and efficient recovery of palladium from reprocessing waste of spent nuclear fuel by mixing the matrix feedstock with a small amount of KI and an appropriate inert solvent (such as kerosene) as collecting agent. Equilibrium of the reaction can be obtained in less than 30 sec. Percent recovery of palladium is more than 97%. Decontamination coefficient is high. No loss of effectiveness of the system was observed below 1×106 rad of irradiation.
A simple, accurate and sensitive method of high performance liquid chromatography (HPLC) with diode array detector was established to identify Xinfeng capsules and systematically evaluated its quality, based on chromatographic fingerprint integrated with the similarity analysis, hierarchical cluster analysis and the quantitative analysis of multi-components by single marker (QAMS). In this study, 18 peaks were selected as the common peaks to evaluate the similarities among different batches (S1–S10) of Xinfeng capsules samples, which were manufactured in the First Affiliated Hospital of Anhui University of Chinese Medicine with a three-year span. Compared to control fingerprint, the similarities values for 10 batches of samples were more than 0.90. Moreover, by analyzing the reference of astragalus, the chromatogram of astragalus was developed, and 10 common peaks of astragalus were identified. More importantly, simultaneous quantification of three markers in Xinfeng capsule, including Calycosin-7-glucoside, calycosin and Formononetinaldehyde was performed, the three constituents showed good regression (R > 0.999) within linear ranges, and their recoveries were within the range of 97.6–101.5%. The validation results showed that the developed method was specific, accurate, precise and robust. This study demonstrated that the developed method offers an efficient, reliable and practical approach for systematic quality evaluation of Xinfeng capsule.
In order to enhance the
electrogenerative leaching rate of sphalerite reasonably, the basic principle
of generative process was applied to the simultaneous leaching of sphalerite
in the presence of MnO2. It was confirmed by experimental
results that both mental ions and electric energy could be obtained in the
simultaneous electrogenerative leaching process. The leaching cell had the
open circuit potential about 1.0 V, about 2000 C of electric quantity was
obtained, the optimal leaching ratio of Zn2+ and
Mn2+ was 48.5, 39.6% respectively, after electrogenerative
leaching for 11 h.
of galena activated mechanically in planetary centrifugal mill were studied.
A dual cell system was introduced to investigate the leaching process. The
experimental results indicated that the mechanical activation improved the
galena’s lattice constant, the lattice distortion and the degree of
crystal defect, which resulted a decreasing of initial potential of galena
electrode and an increasing of output voltage of the leaching cell.
Authors:Fang Wang, Mei Meng, Li Chen, Xiaoyu Wang and Qing Sun
The newly developed high-performance thin-layer chromatography (HPTLC) method allowed for the differentiation of QiYi capsules from 10 batches due to their characteristic fingerprints, proving to be a well-suited method for characterization and assignment of Traditional Chinese Medicine (TCM) preparation. The method was validated for repeatability, intra-precision, and inter-precision. The result was acceptable, with the reference of myotonin, because relative standard deviation (% RSD) was 3.9% in reproducibility test and less than 3.44% in inter- or intra-plate precisions. HPTLC fingerprinting of the extracts showed several peaks with different RF values. Eleven peaks were selected as the common peaks to evaluate the similarities of 10 different samples with RF values ranging from 0.10 to 0.87 according to fingerprint. The similarities of 10 batches of QiYi capsules were more than 0.940; it indicated that the different batches of QiYi capsules were stable and reliable in quality.
Authors:Xixin Wang, Jianling Zhao, Xiaorui Hou, Fang Wang and Chengchun Tang
ZrO2 nanotube arrays were prepared by the anodization method in a mixture of formamide and glycerol (volume ratio = 1:1) containing 1 wt% NH4F and 1 wt% H2O. The catalysts were obtained through the impregnation of zirconia nanotubes with zirconium sulfate aqueous solution followed by calcinating in air at high temperature. The morphology and structure of the nanotubes and catalysts were characterized through scanning electron microscopy, X-ray diffraction, and infrared spectra analysis. Various factors that affect the catalytic activity were investigated in detail. An esterification conversion percentage of 97.6% was achieved for the catalyst prepared with zirconia supports which were pretreated at 500 °C, followed by loading 65% Zr(SO4)2 and calcinating at 400 °C.
Authors:You-Schao Wang, Qou-Fang Cai, Xu-Fang Tan, Chao-Cun Wang and Bo-Rong Bao
N,N,N′,N′-tetrabutylmalonamide (TBMA) was used for extraction of uranyl(II) ion from nitric acid media into n-dodecane. The
effects of nitric acid concentration, extractant concentration, temperature and back extraction on distribution coefficients
of uranyl(II) ion have been studied. The extraction of nitric acid is also studied. The main adduct of TBMA and HNO3 is (TBMA)2·HNO3 in 1.0 mol/l nitric acid solution. The 1:2:2 complex of uranyl(II) ion, nitrate ion and TBMA as extracted species is further
confirmed by IR spectra of the extraction of uranyl(II) ion with TBMA. The values of thermodynamic parameters have also been
Authors:Chu-Fang Wang, Fang-Huang Tu, Su-Ling Jeng and Ching-Jer Chin
This study reports the analysis of Si in airborne particulate matter by laser ablation inductively coupled plasma mass spectrometry
(LA-ICP-MS) as well as X-ray fluorescence (XRF). It was found that Si concentration in airborne particulates collected on
PTFE-membrane filters could be accurately determined with a laser beam operated at 160 mJ free running mode, 6.5 mm defocusing
distance and 0.8 l/min carrier gas flow rate during the LA-ICP-MS measurement. Standard filters prepared by NIST SRM 1648
urban particulates were used for both XRF and LA-ICP-MS not only to establish the calibration curves of Si, but also to examine
the proposed method's effectiveness. The capability of applying both methods for natural sample analysis was also examined.
Particulate loaded filter samples collected from a heavily polluted metropolitan area of Kaoshiung, Taiwan were initially
measured by XRF, then by LA-ICP-MS. An intercomparison between them was thus performed. As a result, both XRF and LA-ICP-MS
proved to be the valid analytical methods for directly determining Si concentrations in airborne particulates on PTFE membrane
Authors:Zhijia Fang, Song Wang, Xiuxiu Du, Ping Shi and Zhiwei Huang
Phosphatidate phosphatase-1 (PAP1) enzymes (yeast Pah1p/Smp2p, mammalian lipin1-3) have a key role in lipid homeostasis by controlling the relative proportions of its substrate phosphatidate (PA) and its product diacylglycerol (DAG). Recent investigation shows that mammalian lipin-1 complements phenotypes exhibited by yeast pah1Δ mutant cells, which indicates the functions of PAP1 enzymes are evolutionarily conserved. The observation was confirmed after transformation of human LPIN1 into PAH1-defective yeast, which resulted in human LPIN1-induced accumulation of triacylglycerol (TAG )and lipid droplet formation. In double mutants lacking Tgl3p and Tgl4p, overexpression of PAH1 or LPIN1 induced TAG accumulation and excessive obesity. Furthermore, the obese yeast was used as a model to study the anti-obesity effects of PAP1 activity inhibitors, including propranolol and clenbuterol. The data showed that the inhibitors significantly suppressed TAG accumulation and lipid droplets formation. These findings demonstrate that LPIN1 plays a functional role in lipid synthesis and storage, a role which is highly conserved from human to yeast. Inhibition of TAG synthesis will become an efficacious treatment strategy for obesity and our excessive obesity model will provide a very useful tool for discovery of new anti-obesity drugs in the future.