5种能源植物种子含油量与脂肪酸组成

能源植物是重要的生物能源原料。为寻找潜在的能源植物,文章采用索氏提取法测定麻风树、曼陀罗、火炬树、苍耳、Kosteletzkya pentacarpos和野西瓜苗的种子油,并采用GC-MS法分析其脂肪酸组成。结果表明,除火炬树(种子含油量为9.50%)外,其他5种植物的种子含油量都在17%以上;5种植物不饱和脂肪酸含量为73.51%～92.23%,且生物柴油主要成分不饱和脂肪酸C18含量为67.9%～92.23%。这些能在边际土地生长的麻风树、曼陀罗、苍耳、K.pentacarpos和野西瓜苗是潜在的能源植物,可用于生物质能源的开发利用。     

基因调控种子含油量研究进展及生物柴油用海滨锦葵遗传改良策略

利用边际土地种植能源植物对解决制约我国生物质产业发展的最大瓶颈——原料不足问题具有重要意义,提高抗逆植物种子含油量对发挥其能源价值尤为重要.文章综述了基因调控植物种子含油量的研究进展,包括反义PEP基因、脂肪酸合成基因、三酰甘油合成关键酶基因和影响甘油-3-磷酸水平关键酶基因等.根据滩涂能源植物海滨锦葵种子油品质特性、种子蛋白质和脂肪酸含量关系及基因调控种子含油量的发展趋势,提出了利用源汇基因强化技术提高海滨锦葵种子含油量的遗传改良策略.     

电感耦合等离子体原子发射光谱法测定铅酸蓄电池用PE型隔板中镍、钴元素的含量

PE隔板在高温下完全灼烧后用(1+4)稀硫酸溶液浸取残渣,采用电感耦合等离子体原子发射光谱法测定浸取液中Ni、Co元素含量。选择测定镍、钴的分析谱线分别为231.604、228.615 nm。按所选仪器工作条件进行光谱测定,并制作各元素的工作曲线。镍、钴的检出限(3 s)分别为0.004、0.002mg/L。对2个样品中的2种元素各测定6次,测定值的相对标准偏差在1.21%~5.86%之间。用标准加入法进行回收试验,测得回收率在96.1%~98.1%之间。     

湿法消解/石墨炉原子吸收法测定土壤铅含量的改进

目的对湿法消解/石墨炉原子吸收法测定土壤中铅含量进行方法改进与探讨,以此实现试验条件的优化。通过使用混合基体改进剂(磷酸二氢铵-硝酸钯溶液),辅以石墨电热消解,用石墨炉原子吸收法对土壤铅样品进行测定。在5.0～50.0μg/L浓度范围内,具有较好的线性关系,检出限为0.03 mg/kg,通过对土壤有证标准物质的多次测定,测定值均在其保证值范围内,相对标准偏差为1.3%～2.3%,相对误差在-1.5%～4.6%。改进后的石墨炉原子吸收法具有较高的灵敏度、精密度和准确度,是一种可用于大规模土壤铅金属含量测定的重要方法。     

基于GIS的山西省木本油料植物分布研究

木本油料植物是生物柴油原料资源,具有保护生态环境的作用。为研究山西省木本植物的分布情况,通过应用系统分类方法和GIS工具分析得到本省含油量高于30%的6种木本油料植物遍布全省,说明本省木本油料植物分布广泛,适合发展生物柴油产业。     

高温燃烧红外热导法测定固体生物质燃料元素的试验研究

基于生物质资源高效清洁能源化利用的目的,对生物质燃料中C、H、N含量的测定技术进行深入研究。在煤的高温燃烧红外热导法基础上对6种固体生物质燃料进行正交条件试验,通过对实验测定结果的统计分析,总结出最佳试验条件:调整主燃烧管温度为930℃、次燃烧管温度为880℃以及调整第二阶段通氧时间为100 s,流量为90 m L/min。将改进的方法与测定条件优化的三节炉和半微量开氏法的测定结果进行对比,测定生物质中C、H、N元素只有不到2%的相对误差,测定周期为5~7 min,证明了改进的高温燃烧红外热导法测定精确度高、操作简便、高效稳定。     

组织样品中二恶英和多氯二苯呋喃快速萃取法研究

分别采用快速萃取法和石统的索氏萃取法萃取组织样品中的二恶英（PCDDs）和多氯二苯呋喃（PCDW），采用高分辨率的气相色谱法，质谱法同位素稀释法进行分析；对两种萃取方法的数据进行比较，结果表明。快速溶剂萃取法具有和索氏萃取法相同的萃取能力，回收率相当，但是节省了大量的时间和试剂。因此，在实验室条件下，快速溶剂萃取法是一种可以替代索氏萃取法的新方法。     

ICP-AES法测定铸铁中Si、Mn、Cr、Ni的研究

研究了ICP-AES同时测定铸铁中的硅、锰、铬、镍4种元素的快速分析方法。通过试验确立了各元素的最佳光谱线和光谱仪合适的工作条件,并确定了各元素的检出限、测定下限,实现了ICP-AES法测定铁的快速分析、测定数据的精密度和准确度结果令人满意,方法快速、简便。     

太阳能热水器得热量的两种测定方法比较

采用排水法和混水法测定太阳能热水器得热量,结果发现排水法测得的得热值明显高于混水法.分析结果表明,这种差异主要因为两种方法之间原理和方法的不同所致,排水法测定的是热水器包括水箱和集热器存留水的全部得热量,混水法测定的仅是可供用户利用的水箱得热量,针对试验样品,提出了混水法中未计入热量的有效解决办法.     

产油酵母发酵醪液油脂提取及溶剂筛选

为建立简易高效的微生物油脂提取方法,文章以圆红酵母发酵醪液为原料,直接用溶剂对其进行处理,评估了24种溶剂的提取性能。研究结果表明：弱极性溶剂,如甲基叔丁基醚、氯仿、二氯乙烷等可直接从圆红酵母细胞中提取油脂,而短链醇类极性溶剂及烃类非极性溶剂均不能提取油脂;使用尼罗红和碘化丙啶对细胞进行染色后发现,极性和弱极性溶剂破坏了细胞膜和脂滴膜,有利于提取胞内油脂;利用低毒性的甲基叔丁基醚和乙酸乙酯处理发酵醪液,油脂提取率分别达到了85%和59%,且所得脂质的组成与酸热法提取的油脂相似。     

Comparison of oil extraction methods,energy analysis and biodiesel production from flax seeds

In recent years, the commercial potential of oil extraction and biodiesel production derived from vegetable seed is being realized. The process energy input requirements are important factors in oil extraction and biodiesel production. This research work investigated oil extraction from flax seeds and compared extraction yield with the energy load. The effect of moisture content on the oil yield was compared between a mechanical oil expeller, organic solvent extraction, organic solvent and microwave assisted, organic solvent and ultrasonic assisted, and combined microwave and ultrasonic with organic solvent. The maximum oil yields % wt/wt from these techniques was 22.6%, 36.3%, 10.0%, 42.0% and 27.8%, respectively. The moisture content had a significant effect on oil yield with the mechanical oil expeller, organic solvent method and ultrasonic assisted extraction, whereas no or little effect was found on microwave‐assisted extraction. The microwave‐assisted extraction showed better results compared with the ultrasonic‐assisted and combined treatment methods. The relative energy consumption of these processes was experimentally investigated; energy ratios were calculated based on the amount of energy recovered to the amount of energy supplied to the flax seed for oil extraction. The net energy ratios showed that microwave‐assisted extraction had the highest (25.21%), followed by organic solvent method (14.04%), ultrasonic method (6.33%) and lowest was with combined ultrasonic and microwave assisted treatment (5.73%). These results showed that flax seed oil can be extracted using microwave‐assisted methods efficiently and in an energy feasible manner. In situ ultrasonic transesterification was applied to powdered samples with 4%, 8% and 12% moisture content (on % dry basis) within an ultrasonic bath having an intensity of 0.124 W/cm². The flax seed biodiesel produced showed a highest conversion yield of 93%, and the effect of different moisture content on the yield showed that 4% moisture content sample produced the greatest biodiesel yield. Copyright © 2013 John Wiley & Sons, Ltd.     

Biodiesel from kernel oil of sweet cherry (Prunus avium L.) seed

Kernel oil of sweet cherry seed (Prunus avium L.) was extracted with hexane in a Soxhlet extractor. Sweet cherry kernel oil contains more than 87% unsaturated fatty acids, such as oleic acid (43.7% by weight), linoleic acid (41.8% by weight), and linolenic acid. The biodiesel from kernel oil of sweet cherry seed in itself is not significantly different from biodiesel produced from common vegetable oils.     

Seed oil of Sapindus saponaria L. (Sapindaceae) as potential C16 to C22 fatty acids resource

Vegetable seed oils have been objects of study as a raw material to produce biodiesel. Considering this, the oil extracted from the seed of Sapindus saponaria L., cultivated in Brazil, was investigated, concerning its chemical composition, aiming at the extraction of potential raw material for the production of biodiesel, for the first time. Seeds were collected at Maringá State University campus. The oil was extracted by means of Soxhlet method and characterized by Gas Chromatography, coupled with Mass Spectrometry (GCMS). The quantity of oil yielded was of 42.58%. The oil characterization allowed the identification and the quantification of seven fatty acids. From these, 57.60% were unsaturated and 42.40% were saturated. Oleic acid was the most abundant (52.45%) among them.     

Thermogravimetric analysis as a new method to determine the lignocellulosic composition of biomass

Biomass energy uses organic matter such as wood or plants - lignocellulosic biomass - for creating heat, generating electricity and producing green oil for cars. Modern biomass energy recycles organic leftovers from forestry and agriculture, like corn stovers, rice husks, wood waste and pressed sugar cane, or uses special, fast-growing “energy crops” like willow and switchgrass, as fuel. Biomass is composed of three major components: cellulose, hemicelluloses, and lignin. Their differences in chemical structures lead to different chemical reactivities, making the relative composition in cellulose, hemicelluloses and lignin in the biomass a crucial factor for process design. In this paper thermogravimetric analysis is investigated as a new method to obtain lignin, hemicellulose and ??-cellulose contents in biomass. It is shown that this alternative method lead to comparable results than common methods used for the determination of the ??-cellulose content, with an enhancement of the accuracy in the determination of the hemicellulose content. Unfortunately, this method cannot be adopted for the determination of the lignin amount.     

Seed oils of Euphorbiaceae from the Caatinga,a Brazilian tropical dry forest

The oil content and fatty acid profiles of Euphorbiaceae from Caatinga, totaling 100 specimens, 33 species and 26 localities were determined. Intraspecific variation of fatty acid profiles were observed in some species. Many samples are potential sources of seed oil with a variety of potential industrial uses. Large seeds with high oil yields characterize species of Cnidoscolus, Croton, Jatropha and Manihot. Most samples contain linoleic acid as main seed oil constituent. Oils with oxidation stability due to high contents of palmitic and oleic acids were obtained from samples of Sebastiania. Samples of Chamaesyce and Euphorbia stand out by high contents of linolenic acid. Some samples of Croton contain substantial contents of azelaic acid.     

Influence of fuel properties on the burning characteristics of sour plum (Ximenia americana L.) seed oil compared with Jatropha curcas L. seed oil

The aim of the research was to determine fuel properties and burning characteristics of sour plum (Ximenia americana L.) seed oil compared with Jatropha curcas seed oil when unblended and blended with kerosene. Fossil oil fuel products have witnessed increased demand all over the world with prices reaching new peaks. Sour plum (Ximenia americana L.) seed oil as one potential biofuel was evaluated to determine its fuel properties as substitute for kerosene. The seed oil was blended with kerosene in varying ratios and the parameters: burning rate and flame height determined. The blended oil was also burned in modified kerosene stove. It was found that Density, viscosity, fire point, carbon residue and ash content influenced its burning parameters. Parameter burning characteristics and energy transfered improved with increasing blend of kerosene. In conclusion, Ximenia americana L. seed oil when blended with kerosene in ratio above 10% can supplement kerosene as biofuel.     

Unique occurrence of unusual fatty acid in the seed oil of Aegle marmelos Corre: Screening the rich source of seed oil for bio-energy production

In this work, an attempt has been made to characterize, isolate and elucidate the structure of unusual fatty acid in the seed oil of Aegle marmelos Corre. Further, this nonedible seed oil is screened for its bio-diesel or industrial feedstock property. The Aegle marmelos Corre seeds yielded 49.0% oil. The seed oil contains 12.5% of 12-hydroxyoctadec-cis-9-enoic acid (ricinoleic acid) along with other normal fatty acids. The identification and characterization was supported by FTIR, ¹H NMR, ¹³C NMR, MS, GC analysis and chemical degradation technique. A good agreement is seen between the calculated and experimental results of iodine value (IV) and saponification value (SV). The prominent parameters of bio-diesel such as cetane number (CN), lower heating value (LHV) and higher heating value (HHV) are deployed to envisage the quality of oil for use as bio-diesel. This seed oil is nonedible and is found to be the alternative feed stock for the production of bio-diesel since it convenes the major specifications of bio-diesel. The bio-diesel property of fatty acid methyl esters (FAMEs) of this seed oil is compared with other bio-diesels.     

Renewable energy sources from Michelia champaca and Garcinia indica seed oils: A rich source of oil

Michelia champaca and Garcinia indica seeds yielded 45.0% and 45.5% of oil. The fatty acid profiles of both the seed oils were examined. The saponification value (SV), iodine value (IV) and cetane number (CN) of fatty acid methyl esters of both the seed oils were empirically determined. The saponification value (SV) and iodine value (IV) are in good agreement with the experimentally observed values. The fatty acid compositions, iodine value and cetane number were used to predict the quality of fatty acid methyl esters of oil for use as biodiesel. Thus, the fatty acid methyl esters of seed oils of M. champaca and G. indica were found to be the most suitable biodiesel and they meet the major specification of biodiesel standards. The selected plants M. champaca and G. indica have great potential for biodiesel. M. champaca and G. indica seed oils were found to contain keto fatty acids along with the other normal fatty acids, respectively. These fatty acids have been detected and characterized by UV, FTIR, ¹H NMR, ¹³C NMR, MS, GC techniques and chemical transformations.     

The influence of seed and oil storage on the acid levels of rubber seed oil, derived from Hevea brasiliensis grown in Xishuangbanna, China

High acid levels, characteristic of rubber seed oil (RSO), limit RSO use in biodiesel production. The aims of this study were to determine the causes of these high acid levels by investigating what affects the storage of rubber seeds and RSO had on the acid levels. Two storage conditions/methods were evaluated, one representing a proposed storage method (SM 1), the other mimicking storage conditions characteristic to the Xishuangbanna region (SM 2). Furthermore, RSO storage was evaluated by testing RSO acid levels over a 2-month period, under standard storage conditions. Seeds from SM 2 displayed increased seed pile temperatures, higher levels of Mildew infection, lower seed oil content and higher acid levels. Low seed oil content and high acid values of SM 2 were resultant of the high Mildew infection and increased seed pile temperatures. In addition, a critical value of 90% relative humidity of seed piles was identified, above which Mildew infection increased sharply. Storage of crude RSO resulted in increased acid values. This data shows that in order to reduce high acid values, seed pile temperature, humidity and Mildew infections need to be kept to a minimum, as well as the storage time of the seeds and the RSO.