A major challenge in the use of brown coal in Victoria, Australia, for power generation is its high moisture content, which results in high greenhouse gas emissions. Predrying technologies for coal ...are one option being considered for use in brown-coal-fired power plants in Victoria to reduce greenhouse gas emissions. Using a validated computational fluid dynamics (CFD) model, this study investigates the combustion of predried brown coal in a 375 MW tangentially fired furnace that was designed for raw or non-predried brown coal. Different operating arrangements of the fuel gas for the predried coal with various moisture contents are proposed and assessed. When predried brown coal is burned with 55% or lower moisture content, the CFD results indicate that additional gas needs to be added to the fuel gas to maintain the original mass flow rate and reduce the heat flux in the furnace. Arrangements with additional air or recirculated flue gas added to the fuel gas are proposed and tested for predried coal with 55, 45, 35, 25, and 15% moisture contents. The increase in the furnace temperature for the recirculated flue gas arrangement is smaller than that of the additional air arrangement, and stack loss is expected to be smaller than for additional air cases. The temperature distributions and wall heat fluxes in the boiler for the recirculated flue gas cases are similar to that of the raw coal combustion case. Therefore, use of recirculated flue gas is proposed as an option for future operation of the furnace with predried coal. Nevertheless, further studies are essential to understand the technical and financial feasibility of using flue gas to maintain the fuel gas flow rate.
pH-responsive molecularly imprinted particles were successfully fabricated by pore-filling poly (acrylic acid) (PAA) gels into bisphenol-A (BPA)-imprinted polyethersulfone particles. The adsorbed BPA ...amount (or rate) decreased after filling the PAA gels both for the imprinted and nonimprinted particles. However, it was confirmed that changing the acidity of the solution reversibly controls the rebinding ability toward BPA and that the BPA uptake of the pore-filled particles exhibited chemical valve behavior at a pH between 3 and 6. This finding can be attributed to the swelling of the PAA gels in the particles. The present methodology provides a simple way to prepare pH-responsive molecularly imprinted materials and is expandable to the imprinting of other hydrophobic molecules, such as dibenzofuran. Also, the results of this work demonstrate the potential of stimuli-responsive molecularly imprinted polymer materials as smart chemicals and as drug-delivery systems.
Highlights • Resveratrol decreases the insoluble Aβ1–42 level in the hippocampus in AD rats. • Resveratrol protects the integrity of the blood–brain barrier in AD rats. • This study can provide ...laboratory evidence for the prevention of resveratrol on AD rats.
To study miroRNA-195 (miR-195) expression in the serum and cancer tissue of patients with gastric cancer and to investigate the relationship between its expression and clinicopathological features of ...gastric cancer.
Sixty-two patients with gastric cancer admitted to our institution were included in the study group, and 36 healthy persons undergoing health check-up at our institution served as control group. miR-195 expressions in the serum, gastric cancer tissue and corresponding paracancerous tissue in subjects of two groups were measured by using quantitative fluorescent real-time PCR (QF-RT-PCR), and the relationship between miR-195 and the clinicopathological features of the cancer was investigated.
miR-195 expression level in the serum of gastric cancer patients was significantly lower than that in the control group (p <0.05). miR-195 expression in gastric cancer tissue was also significantly lower than that in corresponding paracancerous tissue (p <0.05). The results of correlation analysis showed that low expression of miR-195 was negatively correlated with the infiltration depth, the extent of differentiation, the clinical staging and lymph node metastasis, all with statistical significance (p <0.05), but not significantly correlated with tumor locations (p >0.05).
Low expression of miR-195 in patients with gastric cancer may play a certain role in promoting the genesis and development of gastric cancer and it can function as a potential novel tumor marker for the early diagnosis and prognosis evaluation of gastric cancer.
A computational fluid dynamics (CFD) model of a 375 MW brown-coal-fired furnace in the Latrobe Valley, Australia, has been developed using ANSYS CFX 12.0. To improve the model predictions, a coal ...combustion model that takes into consideration carbon monoxide reactions has been utilized in ANSYS CFX 12.0. A level of confidence in the current CFD model has been established by carrying out a mesh independence test and validation against the furnace gas exit temperature (FGET), concentration of flue gas components, total boiler heat supply, and the wall incident heat fluxes measured in the power plant. The validated CFD model is then applied to investigate the effects of several operating conditions at full load, such as different out-of-service firing groups and different combustion air distributions on the coal flame. It is found that the selection of out-of-service firing groups has a considerable effect on coal combustion in terms of high-temperature zone shape and location and distribution of incident radiation heat flux on furnace walls. Model results also indicate that redistributing and increasing the velocity of the combustion air can change the location of the high-temperature zone in the furnace, therefore reducing the peak incident heat flux on the furnace walls. A reduction in peak heat flux is likely to lead to a reduction in furnace wall slagging. This study provides a basis for further assessment of future operation of dried brown coal in the existing furnaces in the Latrobe Valley, which were designed and currently operate using raw brown coal.
The Jingyang South Plateau is located near the right bank of Jinghe river, belonging to Weibei Loess Plateau. Since the large-scale irrigation from 1976s, many river erosion-induced loess landslides ...have occurred in the Jingyang South Plateau. Landslide disasters has seriously affected local economic development and the safety of people's live and property. To better understand the formation mechanism of landslides in this area, this paper uses field investigation, reduced triaxial compression shear test on saturated Q2 loess and numerical simulation to understand the formation mechanism of erosion-induced loess landslides. It is concluded that (1) Under the reduced confining pressure stress path, the yield strength of saturated Q2 loess is related to the initial confining pressure and shear rate. (2) The formation mechanism of river erosion-induced landslide of loess has been proposed: river erosion is the fundamental cause of river erosion-induced landslide of loess, and some blocks of soil laying at the foot of the slope plays a key character for the stability of the slope. This research could be helpful in preventing landslide disasters.
Rational
in silico optimization of the Whelk-O1 chiral stationary phase (CSP) has been carried out based on the chiral recognition mechanism extracted from previous molecular dynamics simulations ...C.F. Zhao, N.M. Cann, Anal. Chem. 80 (2008) 2426 of this CSP. Three modified CSPs have been examined. The first two are designed to increase selectivity by reducing the docking probability of the less retained analyte. The third modified selector reverses the amide bridge to introduce a structural motif found in the popular carbamate-derivatized polysaccharide CSPs Y. Okamoto, M. Kawashima, K. Hatada, J. Am. Chem. Soc. 106 (1984) 5357. For each modified selector, an atomistic model has been obtained through extensive
ab initio calculations. The effect of selector modification is then evaluated via simulations of the modified interface in the presence of target analytes. Simulation results show that the separation factors are increased for the modified CSPs but in some cases elution orders are reversed. The Whelk-O1 CSP was originally designed to separate naproxen W.H. Pirkle, C.J. Welch, B. LAmm, J. Org. Chem. 57 (1992) 3854. With this in mind, molecular dynamics simulations of naproxen are compared for the original, and the modified, selectors.
The effects of Flavomycin, Bacillus licheniformis and Enramycin on broiler performance, nutrient digestibility, gut morphology and the intestinal microflora were studied in a 42-d experiment. A total ...of 288, one-day-old, male, Arbor Acres broilers were randomly assigned to 1 of 4 dietary treatments with 12 pens per treatment and 6 birds per pen. The treatments were comprised of a control diet without supplementation, a diet supplemented with 5 ppm Flavomycin, a diet supplemented with the combination of 5 ppm Flavomycin and 1.35×109 CFU/kg Bacillus licheniformis, as well as a diet supplemented with 5 ppm Enramycin. The average daily gain (ADG) and feed conversion ratio (FCR) of birds fed the diet with Flavomycin combined with Bacillus licheniformis and the Enramycin diet were improved (P<0.05) compared with the control diet. The digestibility of dry matter, energy, and calcium for birds fed the combination of Flavomycin and Bacillus licheniformis and the Enramycin diet were also enhanced compared with the control diet. All additives improved the villus height and crypt depth in the duodenum, jejunum and ileum on d 21. In addition, reduced numbers of cecal E. coli (P<0.01) were found in birds fed all three supplemented diets on d 42. In conclusion, supplementation with Flavomycin and Bacillus licheniformis in combination or Enramycin would appear to be superior to supplementation with Flavomycin alone. All three supplemented diets were superior to the control.
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