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111.
Abstract: Atherosclerosis and its related complications are the leading causes of death in the West and in many developed countries. This study aims to investigate the hypolipidemic effect of bamboo shoot oil (BSO) in Sprague–Dawley rats. A group of rats had induced hyperlipidemia, hypercholesterolemia, and fatty liver by being fed with a high-fat, high-cholesterol diet for 4 wk. The control group was administered 10 mL distilled water per kg body weight, while the other groups were, respectively, administered 250 mg beta-sitosterol, 250 mg BSO, 500 mg BSO, and 1000 mg BSO per kg body weight by oral gavage. The results demonstrated that BSO could significantly decrease the levels of total cholesterol, triacylglycerol, low-density lipoprotein-cholesterol, phytosterol, lipoprotein lipase, hepatic lipase, and atherogenic index in serum, and increase the levels of cholesterol in feces. It could also significantly decrease the level of relative liver weight and liver lipids. The pronounced hypolipidemic effects of BSO might be attributed to its ability to inhibit cholesterol absorption and increase cholesterol excretion. These results suggest that consuming BSO may provide benefits in managing hypercholesterolemia. Therefore, BSO may be a good candidate for development as a functional food and nutraceutical.  相似文献   
112.
Considering the rich sugar beet resource in Xinjiang, China, the possibilities for Hg(II) removal by pectin extracted from sugar beet pulp and optimization of the extraction process using response surface methodology (RSM) were studied. The experiments were proposed by Box‐Behnken design (BBD) and a second‐order regression model was developed for regression analysis and analysis of variance. Optimized conditions in terms of temperature, concentration, and solid‐liquid ratio were determined. The effects of different parameters like pH, time, temperature, and initial Hg(II) concentration on adsorption capacity were investigated. The isotherm adsorption experiments were fitted with the Langmuir model which indicated monolayer adsorption.  相似文献   
113.
该文对竹类的生长和化学组成及其竹纤维特性进行分析,并结合南纸公司竹粘胶浆粕生产实际对竹粘胶浆粕制浆工艺、操作要点进行技术总结。  相似文献   
114.
Batch and continuous studies have been conducted on the treatment of black liquor from a kraft pulp and paper mill by a bacterial strain, Aeromonas formicans. The results of batch studies revealed that the strain was able to remove 71% and 78% of COD and lignin respectively, while the colour removal efficiency was around 86% in 10 days of retention time. The analysis of lignin degradation products by gas chromatography after 20 days of incubation revealed the formation of some phenolic acids, which were responsible for the decrease in pH during batch studies. The removal efficiencies of COD, colour and lignin obtained in continuous reactor studies were 73, 88 and 77% respectively for an 8 day detention period and these efficiencies were almost the same as obtained in batch studies. © 2001 Society of Chemical Industry  相似文献   
115.
Copper/bamboo fabric (Cu/BF) composites were prepared by electroless deposition via a tin-free process. The process involved 3-aminopropyltrimethoxysilane modification, noble metal (Au or Pd) activation and electroless copper planting of BF. The copper deposition rate via Pd catalytic process was 1.01 mg/cm2 h, higher than that by Au catalytic process (0.85 mg/cm2 h). The microstructure of Cu/BF composites was analyzed by scanning electron microscopy (SEM), and the copper coatings were composed of ball-shaped copper particles. The composition and chemical state of copper layers were measured by X-ray diffraction (XRD) and X-ray photoelectron spectroscopy (XPS) spectra, Cu0 was detected but copper dioxide was not found in both spectra. The electromagnetic interference, water absorption, mechanical tension, conductivity and adhesion properties of Cu/BF samples (weight ratio of Cu/BF: 0.36 ± 0.01) were measured to obtain the qualities of the composites.  相似文献   
116.
In situ single‐stage electrochemical bleaching of kraft bagasse pulp was carried out in a cylindrical agitated vessel fitted with four graphite rod anodes and a cylindrical stainless steel screen cathode, using NaCl as an electrolyte. The effect of current density, pH, NaCl concentration, impeller rotational speed, temperature, and pulp consistency on the rate of bleaching was studied. It was found that the rate of bleaching increased with increasing current density, NaCl concentration, and temperature and decreased with increasing pH and pulp consistency. The effect of temperature was found to fit Arrhenius equation with an activation energy of 0.515 kcal/mol, which denotes a diffusion‐controlled mechanism. Energy consumption (EC) calculation showed that EC ranged from 0.225 to 3.11 kWh/kg dry pulp depending on the current density. The strength of bleached pulp was little affected by bleaching lying within an acceptable range.  相似文献   
117.
毛志国 《山西建筑》2009,35(11):311-313
简要介绍了岩溶的成因,并结合工程实例论述了在隧道开挖施工中对不同的岩溶形态进行处理所采取的措施,结果表明,采用地质分析、钻孔勘探和地质雷达探测相结合是进行地质预测预报的有效手段,加强临时支护是穿越岩溶的安全保证措施。  相似文献   
118.
The diversity and dynamics of the dominant bacterial communities arising during the pickling process of bamboo shoots (Dendrocalamus latiflorus) were investigated by nested polymerase chain reaction denaturing gradient gel electrophoresis combined with quantitative real‐time polymerase chain reaction. Results showed only several kinds of halophilic bacteria during early sampling time (0?3 days). After pickling for 7 days, Lactococcus lactis significantly increased (< 0.05, quantities were 6.39 × 105 copies μL?1) and became the first dominant bacterium. After pickling for 14 days, Weissella sp. bands appeared and quickly became dominant on the 21st day (4.07 × 106 copies μL?1). As maturation progressed, Lc. lactis decreased in intensity whereas Weissella sp. increased in intensity. Finally, the quantities of Weissella sp. (2.50 × 107 copies μL?1) became higher than those of Lc. lactis (1.43 × 107 copies μL?1) after pickling for 56 days. The pickling process was initiated by Lc. lactis, followed by Lc. lactis and Weissella sp., and was finally succeeded by Weissella sp.  相似文献   
119.
本文研究了竹子磺化化机浆(SCMP)在 H_2O_2漂白时的反应动力学,并就其发色基团的脱除机理进行了探讨。结果表明:竹子 SCMP 浆 H_2O_2漂白表现出与木材机械浆相似的反应性。竹子 SCMP 浆 H_2O_2漂白初始反应速率很快,此后渐趋平缓。提高漂白浓度,增加药品用量有利于浆中发色基团的脱除。确立竹子 SCMP 浆H_2O_2漂白动力学方程为:—dC_R/dt=k[H_2O_2]~(0.89)[OH]~(0.18)C_R~(5.25)  相似文献   
120.
大麻全杆化机浆H2O2漂白   总被引:2,自引:0,他引:2  
大麻全杆化机浆经H2O2单段漂白后,其白度和物理强度明显增加,达到二号凸版纸标准,漂白纤维变得更柔软,纤维表面变得更整洁,主要发色基因双键和共轭羰基被破坏,芳族邻羟基酮和聚木糖C=0键及甲氧基等被消除.  相似文献   
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