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Fine-mineral separation has been a difficult problem in the mineral-processing field. A new cyclonic-flotation system was designed to solve the fine-mineral-recovery problem. Its design and operation are different from those of other cyclonic-flotation columns. In this study for the new cyclonic column, optimal reagent dosages, solid concentration, and aeration rate were determined. Many factors influence the operation of column flotation; however, in this study, mainly the effect of the circulation rate on the flotation behavior of the wide and narrow particle-size ranges of coal was investigated. The chosen circulation rates were 0.895, 1.044, 1.210, 1.369, 1.461, 1.578, 1.653, and 1.752 m/s. The wide particle size refers to a value of less than 0.5 mm. The narrow particle-size ranges refer to values from -250 to +75 μm, -75 to +45 µm, v45 µm, and +250 µm. The results showed that the combustible recovery of the narrow-size particles increased first and then decreased with the increasing circulation rate. The combustible recovery order of the narrow-size ranges in the same flotation time was as follows: -250 to +75 µm > -75 to +45 µm > -45 µm > +250 µm. [ABSTRACT FROM AUTHOR]

Separation dynamics is useful for practical flotation process guidance and prediction. In this paper, a new column flotation system was designed. Mineral composition and size fraction were analyzed. Flotation rate tests of different circulating rates were conducted using the optimal reagent dosages, solid concentration, and aeration rate. The experimental data showed that flotation rate constant reduced gradually with the time and could be improved through increasing the circulating rate and energy input. [ABSTRACT FROM PUBLISHER]

Slime water is used repeatedly and its treatment is very essential in coal preparation plants. A new method called fractal dimension is proposed to evaluate the performance of slime water treatment. According to settling experiments, the settling process of slime water can be divided into two phases. In the first phase, water hardness is less than 50 DH° and settling velocity is fast. In the second phase, the water hardness is over 50 DH° and settling velocity is slow. Under different water hardness levels, the variation trends of the luminosity of the supernatant liquor, settling velocity, and fractal dimensions are consistent. [ABSTRACT FROM PUBLISHER]

To assess the phytoremediation potential of an autochthonous willow (Salix × aureo-pendula CL'J1011') for phenanthrene (PHE)-contaminated soils and PHE-cadmium (PHE-Cd) co-contaminated soils, we conducted field experiments in the lower reaches of the Yangtze River, China. Ethylenediaminetetraacetic acid (EDTA) and ethyl lactate were tested for individual and combined effects on the phytoremediation efficiency. For PHE-contaminated soils, willow plus ethyl lactate resulted in significant removal of PHE from soils after 45 days, and the PHE concentration in the shoots was significantly higher with than without ethyl lactate. For PHE-Cd co-contaminated soils, both willow plus EDTA and willow plus EDTA and ethyl lactate led to a significant decrease in the concentrations of PHE and Cd in the soils after 45 days, whereas willow alone did not. The PHE and Cd concentrations in the willow shoots were significantly enhanced in the presence of EDTA alone and with ethyl lactate, except for the PHE concentration in stems with EDTA alone. Under the same treatment, the presence of Cd had no significant influence on the PHE removal from soils. The results indicate the feasibility of using this willow together with both EDTA and ethyl lactate for the simultaneous removal of PHE and Cd from soils. [ABSTRACT FROM AUTHOR]

Pr2O3 and Pr6O11 doped ZnO thin films were prepared by the sol-gel method respectively. The microstructure and electrical characteristics of the samples were investigated by X-ray diffraction (XRD), atomic force microscopy (AFM), varistor dc parameter analyser and impedance analyser. Two kinds of Pr-oxide doped ZnO thin film with similar phase which contain well crystallised ZnO. The grains of Pr2O3 doped ZnO thin films and Pr6O11 doped ZnO thin films are uniform and closely packed, and all samples have lower surface roughness. When the doping content of Pr2O3 is 0·90 mol.-%, the varistor properties of ZnO thin film are optimum, the leakage current is 487 μA, the potential gradient is 232 V mm−1 and the nonlinear coefficient is 2·5. The dielectric constant of ZnO thin films increases in a certain degree with different contents of Pr2O3 and Pr6O11 doping. The Pr2O3 doping reduces the dielectric loss effectively, but the Pr6O11 doping has the opposite effect. These results provide favourable theoretical and experimental basis to optimise and extend electrical application of ZnO thin film. [ABSTRACT FROM AUTHOR]

The cyclonic-static microbubble flotation column (FCSMC) has dual effects including the cyclonic separation and airflotation separation with advantages in the oily wastewater treatment field such as the small lower limit of the effective separation size, short separation time, large handling capacity, and low operating cost, especially the polymer-flooding oily wastewater treatment aspect. In this paper, the cyclonic separation function mechanism of the FCSMC was investigated. In addition, several operating parameters which impact oil removal efficiency and kinetics constants such as circulating pressure, the superficial gas velocity and the frother consumption were also investigated. The mathematical model relationship between the separation kinetics constants and the factors including circulating pressure, gas superficial velocity, and the average bubble diameter was established. Based on the strength by steps, the physical separation model of the cyclonic-static microbubble was also established. [ABSTRACT FROM AUTHOR]

Puerarin is a potential therapeutic agent for cardiovascular diseases. But its poor oral bioavailability restricts its clinical application. In present study, as an evaluation of a formulation to improve the bioavailability of the drug, puerarin and its phospholipid complex were given to rats by intragastrically (i.g.) administration to compare pharmacokinetic, tissue distribution, and excretion. Serum samples were obtained at designated times after a single oral dose of 400 mg/kg puerarin or its complex. Tissue samples (heart, liver, spleen, kidney, lung, and brain), urine, and feces were collected and analyzed by a sensitive and specific high performance liquid chromatography (HPLC) method after i.g. administration of puerarin or its phospholipid complex. Compartmental and non-compartmental analyses were applied to the serum concentration versus time data. Pharmacokinetic parameters were calculated using the 3P97 pharmacokinetic software package. An open two-compartment, first-order model was selected for pharmacokinetic modeling. The results showed that after i.g. administration of 400 mg/kg puerarin and its phospholipid complex (equivalent to 400 mg/kg of puerarin), the pharmacokinetic parameters of the two formulations were different. The serum concentrations reached peaks at 0.894 ± 0.521 h and 0.435 ± 0.261 h, respectively, indicating the complex was more readily absorbed in serum than puerarin. The maximum concentrations for puerarin and its complex were 1.367 ± 0.586 mg·L -1 and 2.202 ± 1.28 mg·L -1 and AUC were 5.779 ± 1.662 mg·h. L -1 and 8.456 ± 0.44 mg·h L -1 , respectively, indicating a higher bioavailability for the complex. The widely distribution characteristics of puerarin and its complex in tissues post-i.g. administration was identical and in a descending order as follows: lung, kidney, liver, heart, spleen, and brain. However, the amount was different. Puerarin distribution was higher in heart, lung, and brain after administering the complex. The cumulative 72 h urinary excretion of puerarin after i.g. administration of puerarin and its complex accounted for 1.05%, 1.11% of the administered dose, respectively. The cumulative feces excretion of puerarin was 32.3% and 25.5%. To sum up, oral administration of puerarin phospholipid complex modified the pharmacokinetics and tissue distribution of puerarin and it could be an effective oral formulation for puerarin. [ABSTRACT FROM AUTHOR]

Background Experimental data have suggested that BM-cell implantation can improve infarcted cardiac function. However, the number of implanted cells that survive is still unknown. The present study was performed to investigate whether implantation of autologous BM mononuclear cells (BM-MNCs) transfected with phVEGF 165 can increase the number of surviving implanted cells, and enhance functional improvement of infarcted hearts in rabbits. Methods Acute myocardial infarction (AMI) in rabbits was replicated by ligating the left anterior descending coronary artery, and animals were randomly divided into the following three groups: I AMI control group (n=7); II BM-MNCs transfected with phVEGF 165 implantation group (n=7); III BM-MNCs implantation group (n=7). In addition, sham-operated (n=5) rabbits were randomly selected to serve as a non-infarction control group (VI). Animals for cell implantation received intramyocardial injections of autologous BM-MNCs 14 days after AMI. Echocardiography and hemodynamic studies were performed to evaluate cardiac structure and function 28 days after implantation. The implanted sites were examined using immunofluorescence to identify the phenotypes and number of the labelled cells. Reverse transcriptase (RT)-PCR and Western blot analysis were performed to detect the expression of hVEGF 165 gene and VEGF 165 protein respectively. Results Failed cardiac function produced by AMI was significantly improved in Groups II and III 28 days after cell implantation. BM-MNCs transfected with phVEGF 165 implantation conferred a further improvement of cardiac function, with significant changes of all assessed parameters when compared with BM-MNCs implantation alone (all P<0.05). The implanted cells demonstrated myogenic differentiation with the expression of Troponin T and organized contractile proteins. The positive staining for Factor VIII-related Ag indicated the induction of angiogenesis in the infarct area. The percentage of Brdu-positive myocyte, endothelial cells was 75±6%, 34.1±4.6% in Group II, significantly higher than that in Group III (51±7%, 11.3±2.5% respectively, P<0.05). RT-PCR analysis demonstrated exclusive expression of hVEGF 165 gene in Group II, and Western blot showed the expression of VEGF 165 protein was significantly higher in Group II than in Group III (P<0.05). Conclusions Implantation of BM-MNCs transfected with phVEGF 165 can increase the number of implanted cells surviving, and enhance the impaired cardiac function after AMI. [ABSTRACT FROM AUTHOR]