Degradation of a Victorian brown coal in sub-critical water

Conversion characteristics of a Victorian brown coal in sub-critical water were investigated. Pulverized brown coal was heated up to 623 K in flowing sub-critical water pressurized at 25 MPa. The total conversion of the coal into extract and non-condensable gas reached over 70 wt%-daf, which was appreciably higher than the maximum conversion (50 wt%-daf) with a sub-critical non-hydrogen donor solvent, 1-methylnaphthalene (MN). Laser-ionization-desorption mass spectrometry showed that the sub-critical water extract was richer in lower-molecular-mass compounds than the sub-critical MN one. Thus, degradation of the coal occurred more extensively in sub-critical water than in MN. Along with the conversion in sub-critical water, both the total contents of hydrogen and phenolic hydroxyls in the whole products remained nearly unchanged. This suggests comparable and simultaneous formation and decomposition of hydroxyls through hydrolysis of ethers/esters and dehydration condensation between hydroxyls/carboxyls, respectively. For detecting the hydroxyl formation, the coal was first heated at 623 K under an inert gas atmosphere until the formation of water and the other volatiles was completed. Then, the heat-treated coal (LY-H) was exposed to flowing sub-critical water. As expected, the net formation of phenolic hydroxyls from LY-H was detected as 0.8 mmol-OH/g-LY-H while that of hydrogen as 2.3 mmol-H/g-LY-H. Approximately a half of the hydrogen gain was explained as phenolic hydroxyls gain, suggesting the importance of hydrolysis of esters and ethers that formed carboxyls and alcoholic hydroxyls as well as phenolic hydroxyls.     

Pyrolysis of brown coal under different process conditions

Pyrolysis tests were performed under laboratory conditions, simulating possible processes in the burning of brown coal mines. These tests focused on gaseous products of thermal decomposition of coal and how their concentrations changed depending on pyrolysis temperature. Results obtained can help to quantify the contributions of particular gases to overall explosiveness of a gaseous mixture and can explain the process of explosive gas release during conflagration.     

Nutritional effects of mustard seed protein detoxified with aqueous isopropanol in young rats

The effect of removing anti‐nutritional factors from n‐hexane‐extracted mustard meal using 80% isopropanol (to reduce thioglucosides, phenolics, etc.) on growth, food efficiency ratio, serum and liver lipid profiles and protein content of young rats was examined. For this n‐hexane‐extracted mustard meal was extracted with 80% isopropanol giving a fraction with 68% protein and low residual thioglucoside (0.5%) as well as phenolic (0.3%) content. This isopropanol‐extracted mustard seed protein fraction reduced the growth of young rats slightly when compared with casein. The food efficiency ratio between rats fed isopropanol‐extracted mustard seed protein or casein did not differ, nor did the protein composition affect serum total cholesterol, triglyceride, HDL‐cholesterol, LDL‐cholesterol, VLDL‐cholesterol and LDL‐C/HDL‐C ratio. However, rats fed isopropanol‐extracted mustard seed protein showed a significantly lower (p<0.05) liver cholesterol concentration than rats fed casein. Liver triglyceride and phospholipid concentrations did not differ between rats fed the two proteins, nor was serum protein affected. This study indicates that extraction of hexane‐extracted mustard meal with 80% isopropanol reduced a number of anti‐nutritional factors like thioglucoside and phenolics. Furthermore the nutritional quality of mustard seed protein fraction is comparable to casein in respect to growth, food efficiency ratio, serum lipid and protein concentrations and organ weights.     

Treatments of low rank coals for improved power generation and reduction in Greenhouse gas emissions

Reduction in ash constituents by water washing, and also at specific pH values, was systematically studied for three low-rank coals. Acid treatment removed inorganic constituents if accompanied by efficient water washing; at elevated temperatures this can also reduce moisture. The ash components are present in the coal matrix and also as numerous aluminosilicates particles containing K, Na, Mg, Fe and Ca; acid treatment reduced the ash constituents to mainly quartz and clay particles. The ash chemistry of treated and untreated coals was studied over the temperature range 800 °C to 1400 °C. The ash from treated coals consisted mostly of α-quartz, and when heated at 800 °C to 1500 °C, was transformed into mainly amorphous silica and cristobalite, and melted at 1300–1500 °C. Ash from untreated coals melted at or below 1100 °C. The impact of low rank coals with lower moisture, and also coals with lower ash and moisture, was assessed for power generation using the GateCycle™ package. The results show: (i) moisture reduction lowers CO₂/MWh by a small amount but often increases fouling, and (ii) reduction in ash and moisture would eliminate ash fouling and significantly reduce the CO₂/MWh compared with current power plant.     

鸡爪芋化学成分研究

鸡爪芋在广东民间用于治疗胃病、肝炎,有特效。为研究其有效成分,对鸡爪芋干燥根茎95％乙醇提物进行了分离。通过反复柱层析分离、离心薄层色谱分离,重结晶等方法分离得到8个晶体,它们是分别是豆甾醇、β-谷甾醇、棕榈酸、棕榈酸乙酯、十六酸单甘油酯、9,12,15-三烯十八酸乙酯、二十二酸乙酯、葫萝卜甙。     

Sex-Related Differences in Murine Models of Chemically Induced Pulmonary Fibrosis

We developed two models of chemically induced chronic lung injury and pulmonary fibrosis in mice (intratracheally administered hydrochloric acid (HCl) and intratracheally administered nitrogen mustard (NM)) and investigated male–female differences. Female mice exhibited higher 30-day survival and less weight loss than male mice. Thirty days after the instillation of either HCl or NM, bronchoalveolar lavage fluid displayed a persistent, mild inflammatory response, but with higher white blood cell numbers and total protein content in males vs. females. Furthermore, females exhibited less collagen deposition, milder pulmonary fibrosis, and lower Ashcroft scores. After instillation of either HCl or NM, all animals displayed increased values of phosphorylated (activated) Heat Shock Protein 90, which plays a crucial role in the alveolar wound-healing processes; however, females presented lower activation of both transforming growth factor-β (TGF-β) signaling pathways: ERK and SMAD. We propose that female mice are protected from chronic complications of a single exposure to either HCl or NM through a lesser activation of TGF-β and downstream signaling. The understanding of the molecular mechanisms that confer a protective effect in females could help develop new, gender-specific therapeutics for IPF.     

换气包装技术与榨菜包装的改进

本文从榨菜和榨菜的变质谈起，着重介绍了换气包装技术及其工业化生产的意义和榨菜包装的改进。     

降水酸度时间序列的长程相关性

利用R/S分析方法分析了分别来源于美国North Dakota(1980～2000年)及我国常德市(1990～1999年)的降水酸度月均值时间序列,证实了降水酸度时间序列中存在长程相关性.其Hurst指数H>0.5,表明其变化表现为分形布朗运动,各月份降水酸度值是相互关联的.长程相关的时间可达8～9年,表明长程相关性是降水酸度趋势预测中必须考虑的重要因子。     

Preparation of magnetically separable mesoporous activated carbons from brown coal with Fe_3O_4

Magnetically separable mesoporous activated carbon was prepared from brown coal in the presence of Fe_3O_4 as a bi-functional additive. Magnetic activated carbon(MAC) was characterized by lowtemperature nitrogen adsorption, scanning electron microscopy(SEM), transmission electron microscopy(TEM), X-ray diffraction(XRD), X-ray photoelectron spectroscopy(XPS) and vibrating sample magnetometry(VSM). The evolution behaviors and transition mechanism of Fe_3O_4 during the preparation of MAC were investigated. The results show that prepared MAC with 6 wt% Fe_3O_4 addition having a specific surface area and mesopore ratio of 370 m~2·g~(-1) and 55.7%, which meet the requirements of adsorption application and magnetic recovery. Highly dispersed iron-containing aggregates with the size of 0.1 lm in the MAC were observed. During the preparation of MAC, Fe_3O_4 could enhance the escape of volatiles during the carbonization. Fe_3O_4 could also accelerate burning off the carbon wall during activation, which leads to enlarging micropore size, then resulting in the generation of mesopore and macropore. As a result, a part of Fe_3O_4 converted into FeO, FeOOH, a-Fe, c-Fe, Fe_2 SiO_4 and compound of Aluminum-iron-silicon.The prepared activated carbon, which was magnetized by both of residual Fe_3O_4, reduced a-Fe and cFe, can be easily separated from the original solution by external magnetic field.