Search Results

You are looking at 1 - 10 of 52 items for

  • Author or Editor: Fang Wang x
Clear All Modify Search

Abstract

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.

Restricted access

Abstract  

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.

Restricted access

Abstract

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.

Open access

Abstract  

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.

Restricted access

Abstract  

The electrogenerative-leaching 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.

Restricted access

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 R F values. Eleven peaks were selected as the common peaks to evaluate the similarities of 10 different samples with R F 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.

Restricted access

Abstract

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.

Restricted access

Abstract  

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 calculated.

Restricted access

Abstract  

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 filters.

Restricted access

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.

Restricted access