利用气相色谱/质谱联合技术研究核桃仁油脂酸组成

分别以乙醚、正己烷为溶剂,采用索氏提取法和超声波提取法对核桃仁中的核桃油进行提取。用两种甲酯化方法对核桃油进行处理,通过GC/MS方法分析了核桃油中脂肪酸的组成和含量。从核桃油中共检出13种脂肪酸,除亚油酸等5种文献报道过的主要成分外,还包括十四烷酸(肉豆寇酸)、十五烷酸、十六碳烯酸、十六碳二烯酸、十七烷酸、二十烷酸(花生酸)以及二十碳烯酸和二十碳三烯酸等8种含量较少的成分,约占核桃油脂肪酸总量的1.7%。     

马兰籽油中脂肪酸的GC—MS分析

采用索氏提取法对马兰籽中马兰籽油进行了提取,进行甲酯化处理后,以气相色谱．质谱联用仪进行了分析．结果表明：马兰籽油中共鉴定出16种脂肪酸,占马兰籽油总量的98．66％,在马兰籽油中鉴定出的脂肪酸主要为十八碳二烯酸、十八碳烯酸、十六酸．     

三叶鬼针草的化学成分研究

以产自海南的药用植物三叶鬼针草的地上部分为实验研究对象,通过乙醇常温浸泡提取,不同极性溶剂萃取,结合硅胶柱色谱、葡聚糖凝胶Sephadex LH-20柱色谱、重结晶等方法进行化学成分的分离纯化研究,并通过现代波谱方法结合文献数据对比鉴定化合物的结构。结果显示,从三叶鬼针草的地上部分中共分离得到12个化合物,分别为没药烯(1),7α-羟基-β-谷甾醇(2),豆甾-4-烯-3β,6α-二醇(3),豆甾醇-7-酮(4),7-甲氧基-6-羟基香豆素(5),1-棕榈酸甘油酯(6),3β-O-(6'-十六烷酰氧基-β-吡喃葡萄糖基)-豆甾-5-烯(7),1-O-β-D-吡喃葡萄糖-(2S,3R,8E)-2-[(2'R)-2-羟基棕榈酰胺]-8-十八碳烯-1,3-二醇(8),葱木脑苷(9),(3S,5R,6S,7E)-5,6-环氧-3-羟基-7-巨豆烯-9-酮(10),3-羟基二氢猕猴桃内酯(11),2β,3β-二羟基-2α-甲基-γ-内酯(12)。其中,化合物(7)~(12)为首次从该植物中分离得到,对该药用植物资源的合理开发利用具有一定指导意义。     

细基江蓠化学成分研究

从细基江蓠中分离及鉴定出十五碳酸甘油酯(1),全饱和的神经酰胺(2),N-苯基-2-(艹佘)胺(3),24-亚甲基胆甾醇(4),硬脂酸和硬脂酸甲酯等6个化合物。其中1和2为新化合物,3和4是在细基江蓠中首次发现。     

松乳菇挥发性化学成分的GC/MS分析

采用同时蒸馏萃取方法对松乳菇挥发性成分进行提取,并用气相色谱—质谱法对提取物进行化学成分分析.从同时蒸馏萃取提取物中鉴定出了67个成分,并以归一化法测定了各个成分的质量分数.其中超过2%的有9种：1-辛烯-3-醇（2.27%）,丁酸丁酯（13.52%）,（E）-2-辛烯醛（2.88%）,n-癸酸（4.99%）,[1 aR-（1 a..α,4..β,4 a..β,7..β,7 a..β,7b..α）]-十氢-1,1,4,7-四甲基-1H-环丙烯并[e]薁（4.16%）,n-十六烷酸（4.75%）,（Z）-9,17-十八碳二烯醛（5.19%）,（E）-9-十八碳烯酸（3.33%）,十八烷酸（2.13%）.     

柠檬种子油脂化学成分研究

采用丙酮提取柠檬种子油脂,GC-MS联用仪对油脂化学成分进行分离鉴定.并采用面积归一化法确定各成分的相对质量分数.分析检测出100多种化合物,其中20种化合物峰明显,含量排在前五位的化合物依次为:(Z,Z)9,12-十八碳二烯酸(32.525%);十三烷酸(21.639%);油酸,3-羟基丙基酯(6.37%);环己羧酸,十五烷基酯(4.894%);十八烷酸(3.749%).柠檬种子油脂中的主要成分为脂肪酸,包含酸类、酯类、烯烃类等化合物.     

十四酸、十六酸的热容和熔化焓

用精密自动绝热量热计测定了两种分析纯级脂肪酸十四酸和十六酸在80～370K温区的热容,获得固液熔化相变的热力基础数据:熔点分别为326.998K和335.934K,熔化焓分别为45.876kJmol~(-1)和49.065kJmol~(-1),熔化熵分别为104.5JK~(-1)mol~(-1)和146.4JK~(-1)mol~(-1)。     

白鲜皮中脂肪酸化学成分的GS-MS分析

通过建立脂肪酸成分提取及气相色谱质谱检测方法,对白鲜皮中脂肪酸进行提取并进行气相色谱质谱定量分析.采用索氏提取法提取白鲜皮中脂肪酸成分,利用气相色谱-质谱(GC-MS)联用技术进行分析鉴定,运用面积归一化法确定其相对百分含量.从白鲜皮中提出18种脂肪酸,并对成分进行鉴定,脂肪酸中主要成分是亚麻酸(38.76％),木蜡酸甲酯(20.67％),14-甲基十六酸甲酯 (19.55％)等不饱和脂肪酸.     

棉籽油中脂肪酸的GC-MS分析

采用索氏提取法对棉花籽中棉籽油进行了提取,采用硫酸进行甲酯化处理,以气相色谱-质谱联用仪进行了分析,共分离鉴定出10种脂肪酸,共占棉籽油总量的97.67%.其中主要成分为:棕榈酸25.92%,8-十八碳烯酸11.78%,亚油酸37.50%和油酸16.00%.     

花生油与紫苏种子油脂肪酸组分的比较研究

采用化学法萃取和GC-MS法对花生和紫苏种子的含油率及其脂肪酸组分进行研究。实验结果表明,花生的含油率为34.60%,紫苏种子的含油率为39.40%。GC-MS分析结果表明,花生油中共检测出8种脂肪酸组分,即:亚油酸、油酸、棕榈酸、硬脂酸、山嵛酸、10-十八碳烯酸、花生酸、花生一烯酸;紫苏种子油中共检测出5种脂肪酸组分,即:棕榈酸、亚油酸、α-亚麻酸、硬脂酸和10-十八碳烯酸。花生油中脂肪酸的主要组分是亚油酸53.05%、油酸31.74%、棕榈酸7.95%;紫苏种子油脂肪酸的主要组分是α-亚麻酸80.06%、亚油酸11.83%、棕榈酸5.37%。花生油和紫苏种子油中不饱和脂肪酸的含量分别为85.21%和92.81%。     

卡思卡特城堡

It is worthy of noting that, whilst Crookston Castle witnessed the earlier and happier portion of Mary's variegated life,     

不同的吃喝玩乐

一、吃和喝吃苹果 eat an apple, 吃药 take medicine,吃糖 have some sweets,吃饭 have one's meals,吃馆子 dine out,吃惊 be surprised/     

漏洞百出的教育

Many college freshmen arrive woefully unprepared to do college work, and as disadvantaged populations continue to grow, the share of the American work force that has made it through college is expected to plummet. Many experts blame that educational failure not just on high schools but also on colleges. School & College, a special report by The Chronicle, looks at efforts to fix the system. What reforms would better prepare students for college? What should schools and colleges be doing differently? How should state and federal officials help?     

只要努力,不要后悔

There are numbers of crossroads on our long and unpredictable life journey where we totally have no idea about which direction to choose. No matter what our decision is, we should not turn back, but face the music and go ahead instead. I am this kind of girl who always does try without regretting, one example is how I dealt with my love.     

浅谈移民问题

Migration occurs behind a variety of reasons and has a great effect on the whole world. People may migrate in order to improve their economic situation, or in order to escape civil strife, persecution, and environmental disasters. The impact of migration is complex, bringing both benefits anddisadvantages. This paper briefly talks about the causes of migration, the allocation of benefits, and the ways in which individual countries and the international community deal with this important subject.     

Sister Carrie, an Adherent of Desires

Sister Carrie is one of the most controversial characters in American literature.Thought as a "fallen woman" firstly,she was defined as a "new woman" by some critics later. However, by digging into the motivaton behind the whole process of Carrie's "success", the relationship between Carrie and her creator (the author), the social conditions of then American, it can be found that Carrie has never been free-standing on her thought and she has never found her real-sdf even after becoming a famous actress. In a society dominated by mass consumerism Carrie is only an adherent of her own desires. She also is a representative of all those country girls flooded into cities, a symbol and a sacrifice of the urbanization of America in a time countryside was overcome by cities.     

Improvement of one-cycle controller by use of proportional integral differential controller

1.IntroductionOne-cyclecontrolmethod,whichwasproposedaboutonedecadeago[1],hasbecomeanattractivemethodinspecialfieldssuchaspowerfactorcorrection[2-6],switchingamplifiers[7,8],etc.Themainideaofthiscontrollerisbasedonintegrationofdiodevoltageinone-cycleandforcesittobeexactlyequaltothereferencevalue.Themainadvantageofthiscontrollerisitsrealtimeabilitytorejectthevariationofinputvoltage[1].Despitethisgreatability,ithasnogoodperformancesinrejectingofloaddisturbanceandfollowingreferencecommands.Espec…     

库克斯顿城堡

城堡, 是欧洲典型的建筑之一, 每个城堡都有一个美丽的传说或是一段历史。从本期开始, 我们将推出“城堡之旅”, 带各位读者去浏览、观赏欧洲各地的城堡, 开始一段文化与历史的旅途!     

The Reader Response Approach to Teaching of English Literature

During interview with English majors, it was found that a majority of students expressed disappointment with their experience of English literature classes. Students' dislike of learning English literature appears to be the major problem of teaching English literature in China. Reader response approach is a good way to solve this problem. In this paper, I explain the rationale behind the reader response approach, such as its origin, definition, features, assumptions, and strategies. Then I illustrate how reader response approach works as a teaching strategy by presenting several teaching models. At last I evaluate its usefuiness for teachers and present the advantages of reader response approach in Chinese context.