羧甲基蔗渣木聚糖的合成与表征

以蔗渣木聚糖和一氯乙酸为主要原料,乙醇水溶液为溶剂,冠醚为催化剂,经碱活化、醚化反应两步合成了羧甲基蔗渣木聚糖。考察了物料摩尔比、反应时间、反应温度和溶剂中水含量等因素对合成工艺的影响,确定的较佳工艺条件:n(蔗渣木聚糖结构单元)∶n(氢氧化钠)∶n(一氯乙酸)=1∶3.25∶1.25,溶剂V(乙醇)∶V(水)=4∶1,45℃碱化2 h,70℃醚化3 h,所得羧甲基化产物的取代度可达0.59。用FTIR与SEM对原料和产物的结构进行了表征。热分析表明,反应后蔗渣木聚糖在234~312℃内分解量由总质量的46.27%降至30.58%。质量浓度为12 g/L的产物水溶液的表面张力为63.6 mN/m。     

Thai Tea Seed Oil and Virgin Olive Oil Similarly Reduce Plasma Lipids: A Pilot Study within a Healthy Adult Male Population

The potential cardiovascular benefit of virgin olive oil (VOO) is widely recognized. However, the use of VOO at very high cooking temperatures makes these oils poorly suited for many Asian dishes. The use of tea seed oil (TSO) is increasing in Thailand, with TSO having a higher smoke point than VOO. The current study examines the effects of daily TSO intake in healthy adults. In a randomized, single-blind crossover design, 12 men consumed for 3 weeks 40 g day⁻¹ of food prepared with either TSO or VOO as a cooking oil. Plasma lipids, thiobarbituric acid reactive substances (TBARS), and oxidant defense enzyme activities are measured before and after each 3-week intervention period. Gas chromatography analysis of TSO and VOO demonstrates that both oils are equally high in monounsaturated fatty acid. The dietary incorporation of TSO and VOO for three weeks reduces low-density lipoprotein cholesterol (LDL-C) concentrations by 15% and 13%, respectively; with total cholesterol (TC) levels lowered by 10% in both groups. No significant changes in TBARS or antioxidant enzyme activity is observed. These results support the concept that Thai TSO can be utilized as a suitable and healthy alternative oil for high-temperature cooking in many Thai and Asian diets. Practical Applications: Tea seed oil from Camellia oleifera grown in Thailand has been recently reported to favorably lower lipid profiles in hamsters fed a high-fat diet in a manner similar to feeding refined olive oil or grapeseed oil. A pilot crossover trial is conducted to compare the effects of three weeks of daily intake of either TSO or VOO in healthy human adults. Consumption of both oils produced significant reductions in TC and LDL-C. Thai TSO leads to favorable lipid profiles and is a reasonable choice for many Thai and Asian food recipes.     

偶联剂与甘蔗渣／PVC复合材料性能的研究

分别用硅烷偶联剂KH560和钛酸酯偶联剂NDZ311对甘蔗渣/PVC复合体系进行处理。研究了两种处理方法对甘蔗渣/PVC复合材料力学性能、界面形态、耐水性能和加工性能的影响。结果表明,与未处理的相比,两种处理方法都改善了甘蔗渣和PVC之间的界面相容性,界面黏结得到增强,使复合材料的强度和韧性有了较大的提高,同时改善了甘蔗渣/PVC复合材料的加工性能。钛酸酯偶联剂处理对甘蔗渣/PVC复合材料性能的影响更为显著,当其用量为1%时,复合材料的拉伸强度和冲击韧性均得到提高,其中拉伸强度提高了55%。     

树脂吸附-超滤协同分离甘蔗渣碱法半纤维素

针对碱法提取半纤维素中木质素含量高、纯化难的问题,通过疏水树脂吸附-超滤协同处理,探讨纯化分离方式的影响。利用离子色谱（IC）、紫外分光光度计（UV）、凝胶渗透色谱（GPC）和热重量分析（TGA）,对半纤维素的化学组分、分子量、热稳定性等特性进行了分析。结果表明,树脂吸附-膜超滤处理能有效脱除木质素,获得较高分子量的半纤维素,分子主链结构没有发现明显变化,热稳定性略有提高。经树脂吸附后的半纤维素侧链单元有较为明显的变化,分子量较小的半纤维素带有更多侧链木质素单元,通过苯基糖苷键（PhGlc）与碳水化合物相连,可通过树脂吸附-超滤协同处理分离出来,从而达到分离不同侧链结构的半纤维素。     

Stable isotope characterization of olive oils: II-deuterium distribution in fatty acids studied by nuclear magnetic resonance (SNIF-NMR)

Site-specific isotope fractionation of hydrogen was investigated, at natural abundance, by deuterium nuclear magnetic resonance (SNIF-NMR) on nearly two hundred olive oil samples. Owing to the complexity of the ²H-NMR spectra of the mixtures of fatty acids obtained after hydrolysis of the oils, the different signals were gathered into six clusters. Knowing the contribution to the clusters of each of the four fatty acids considered (C_16:0, C_18:0, C_18:1, and C_18:2) and the composition of the fatty acids in the mixture, it is possible to compute the site-specific isotope ratios of the clusters from the molar fractions obtained from the ²H-NMR-spectra and from the total isotope ratio of the mixture, determined by isotope ratio mass spectrometry (IRMS). The results are discussed in terms of geographical (country, region and elevation) and temporal (year) parameters and they are tentatively explained on a climatic basis.     

Classification of virgin olive oils of the two major cretan cultivars based on their fatty acid composition

Fatty acid composition was determined for 105 virgin olive oil samples of the two dominant Cretan olive cultivars, Koroneiki and Mastoides, harvested from different producing areas at different maturity stages. The oils of the Koroneiki cultivar were characterized by lower concentrations of oleic and decaheptanoic and higher concentrations of linoleic and palmitic acids. Oils obtained from high-altitude locations were rich in monounsaturated fatty acids, while oils obtained from low-altitude locations had higher content of saturated fatty acids. Palmitic and palmitoleic acids increased with increasing altitude in both cultivars examined. The statistical analysis of the compositional data showed significant potential for the classification of the samples according to cultivar and location of origin.     

High-performance liquid chromatography evaluation of phenols in olive fruit, virgin olive oil, vegetation waters, and pomace and 1D- and 2D-nuclear magnetic resonance characterization

Phenolic compounds are the most important antioxidants of virgin olive oil. This paper reports on the application of solid phase extraction (SPE) in the separation of phenolic compounds from olive fruit, olive oil, and by-products of the mechanical extraction of the oil and the complete spectroscopic characterization by nuclear magnetic resonance of demethyloleuropein and verbascoside extracted from olive fruit. SPE led to a higher recovery of phenolic compounds from olives than did liquid/liquid extraction. SPE also was used to separate phenolic compounds from pomaces and vegetation waters. Phenylacid and phenyl-alcohol concentrations in extracts obtained from SPE and liquid/liquid extraction were not significantly different (P<0.05). The recovery of the dialdehydic form of elenolic acid linked to 3,4-(dihydroxyphenyl)ethanol and an isomer of oleuropein aglycon, however, was low.     

浅析江联公司对甘蔗渣锅炉的开发设计

文章介绍了28t/h、40t/h燃蔗渣锅炉的设计思路、结构特点、汽水流程特点、冷热风管道系统,锅炉验收成功也标志着江联公司的设计制造技术及IS09001质量管理水平达到了较高的国际水准.     

提高纸浆和纸质量的新方法——用温和的高锰酸钾溶液处理成浆

报导了用高锰酸钾溶液处理漂白针叶木浆和蔗渣浆,以提高纸浆和纸质量,用0.25%～2%高锰酸钾(以纸浆重量为基准)溶液漂白后打浆的浆料明显改进纸页性质,即提高裂断长和白度。漂白针叶木浆经温和的高锰酸钾溶液处理可降低聚合度(DP)32%,氧化后半纤维素和较低DP浆料起着提高纸页强度作用,裂断长增加25%。漂白蔗渣浆经温和的高锰酸钾处理也能提高纸页裂断长和白度。     

甘蔗渣对中性红的吸附性能的实验研究

对甘蔗渣进行了吸附去除印染废水中的中性红模拟实验研究。考察了甘蔗粉用量、pH、吸附时间、中性红初始浓度和温度等因素对吸附效果的影响,探究了其吸附动力学及吸附规律。结果表明,甘蔗粉用量、pH、吸附时间和中性红初始浓度、温度等因素对甘蔗粉吸附水中中性红有显著影响。适宜的吸附条件为:甘蔗粉用量0.6g/100mL,pH6.0～7.0,吸附时间60min,初始浓度100mg/L,温度30℃。在该条件下,中性红的去除率达91%以上。甘蔗粉对中性红的吸附过程可以用Langmuir、Temkin等温吸附方程和二级吸附速率方程进行很好的描述,主要表现为物理吸附。