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1.
[目的]分析海拔高度对长白山地区人参挥发油含量及其成分变化的影响及规律.[方法]采用水蒸汽蒸馏法提取人参中的挥发油,用归一化法测定各组分的体积分数,并采取气质联用(GC-MS)对挥发油中单体成分进行鉴定及含量测定.[结果]生长于不同海拔的4年生人参中挥发油的含量及其成分有显著差别.[结论]海拔高度对于人参挥发油的含量及其成分均有一定的影响,人参挥发油的含量随海拔的升高而增加.  相似文献   

2.
[目的]客观揭示南疆地区鲜食冬枣的品质.[方法]采用HPLC、GC-MS等方法对冬枣的营养及挥发性成分进行分析.[结果]冬枣含有V<,c>含量(161.859 3±13.509 2)mg/100 g鲜枣,总糖(55.384 5±2.539 2)%.总酸(1.384 7±0.115 5)%,粗脂肪(4.275±0.191)%,cAMP(0.228±0.020)mg/g,检出15种氨基酸(包含6种必需氨基酸).挥发性成分中鉴定出40种化合物.其主要成分为酯类、烷烃类、醇类和胺类.[结论]冬枣是一种有较高营养价值的水果.  相似文献   

3.
采用热脱附、固相微萃取、同时蒸馏萃取三种不同前处理方法对牛肉香精挥发性风味成分进行提取,利用气质联用仪分析,比较3种方法对提取物种类及提取量的差别.结果显示,3种方法对提取组分的选择性各不相同,如需全面了解样品的香气构成且实验时间允许,应以多种方法综合使用,相互补充.  相似文献   

4.
[目的]研究小叶水蜡树鲜花挥发油成分,为小叶水蜡树的开发利用提供科学依据.[方法]采用水蒸气蒸馏法提取挥发油,并通过气相色谱-质谱联用技术(GC-MS)对其成分进行分析和鉴定.[结果]在小叶水蜡树鲜花挥发油中共鉴定了28种成分,其主要成分为壬醛(14.24%)、正二十烷(10.21%)、芳樟醇(9.26%)、壬烷(8.46%)、二十二烷(8.06%)、丁香酚(6.74%)、苯乙醇(5.39%)和顺-9-二十三烯(5.25%)等.[结论]试验分析的小叶水蜡树鲜花挥发油主要化学成分与文献有一定差异,这可能与提取方法、色谱柱的选择以及植物在生物合成过程中受到的一些生物酶与环境因素的影响有关.  相似文献   

5.
[目的]分析黔北地区白苞蒿挥发油化学成分.[方法]采用水蒸气蒸馏法提取挥发黔北地区白苞蒿挥发油;采用气相色谱-质谱(GC-MS)联用技术对其挥发油成分进行分析.[结果]从黔北地区白苞蒿挥发油中分离并鉴定出64种化合物,占挥发油总量的94.662%.其主要成分是以萜类为主,其中以左旋薰衣草醇(17.781%)和吉马烯D(11.963%)含量最多.[结论]黔北地区白苞蒿挥发油成分种类较丰富的是广东白苞蒿,其共有成分中仅有β-金合欢烯、橙花菽醇、匙叶按油烯醇、石竹烯氧化物和姜烯,且石竹烯氧化物和匙叶桉油烯醇在2个不同地区白苞蒿样品中含量差异相对较大.  相似文献   

6.
[目的]分析高河菜脂溶性化学成分,为高河菜的开发利用提供试验依据.[方法]采用气相色谱-质谱联用(GC-MS)技术分离鉴定脂溶性成分,用峰面积归一化法计算各成分相对百分含量.[结果]共鉴定出38种组分,占总成分含量的80.80%,其中植醇(26.49%)、乙基胆甾醇(10.65%)、2-甘油-亚麻酸脂(7.84%)和亚麻酸甲酯(7.16%)含量较高.[结论]高河菜脂溶性成分主要为萜类、脂肪酸酯、甾醇和烷烃类化合物,为高河菜的科学利用提供了试验依据.  相似文献   

7.
猴头菌(Hericium erinaceus)是珍贵的食药用菌,除具有丰富的营养成分外还具有抗溃疡、增强免疫、抗肿瘤、降血糖、抗衰老等功效.简要介绍了近几年关于猴头菌较新生物活性成分、药理作用方面的研究进展.  相似文献   

8.
五味子多糖是五味子的一种主要活性成分,具有多种药理作用和生物活性功能,是目前的一个研究热点.本文对五味子多糖的提取、纯化以及药理活性等方面进行综述.  相似文献   

9.
[目的]分析和鉴定假臭草地上部分挥发油化学成分.[方法]采用常压水蒸气蒸馏法提取新鲜假臭草的挥发油,气相色谱-质谱联用技术分析其成分,通过NIST 化合物谱库检索,以峰面积归一化法计算得到所提取各组分在该化学成分中的相对百分含量.[结果]经毛细管分离出27 个峰.确认了其中的26种化合物,占挥发油总量的99.58%.新鲜假臭草挥发油的主要化学成分为:大牛儿烯D,含量23.63%;石竹烯,含量14.95%;α-杜松醇,含量8.00%;6-亚甲基-1,5,5-三甲基-环己烯,含量6.79%;(+)-表-双环倍半水芹烯,含量6.02%.[结论]新鲜假臭草挥发油成分主要是萜类,还含有少量的羧酸和芳香类化合物.  相似文献   

10.
[目的]通过研究椿皮挥发油的化学成分,为椿皮的开发利用提供理论依据.[方法]运用水蒸气蒸馏法提取椿皮挥发油,采用气相色谱-质谱联用技术(GC-MS)对挥发油成分进行分离鉴定,并采用面积归-化法确定各成分的相对百分含量.[结果]从椿皮挥发油中共鉴定出53个化学成分,占挥发油总量的88.02%,其中相对百分含量较高的有(+)-Spa-thulenol(11.59%)、顺-α-可巴烯-8-醇(8.37%)、α-胡椒烯(5.87%)、△-杜松烯(5.76%)、α-荜澄茄油烯(4.40%).[结论]该法简便、快速、灵敏度高,分离度好,是分析椿皮挥发油成分的有效手段.  相似文献   

11.
Some theories of personality hold that an individual's perception of others is influenced by his own personality characteristics; more specifically, that a trait of low social value will be projected more into others, and that insight into the possession of these characteristics reduces this distortion. These 2 hypotheses were tested by having a group of college students rate each other (including themselves) on degree of friendliness or hostility. Agreement with group rating about self yielded the insight score. In general, the hypotheses were supported; the "friendly" Ss were most accurate in their perception of others, and insight was positively associated with accurate perception. From Psyc Abstracts 36:04:4HL16M. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   

12.
The rates of infection of two methods of external ventricular drainage in use at Atkinson Morley's Hospital--namely, (a) percutaneous drainage with Rickham reservoirs and (b) tunnelled ventriculostomies--were compared in this retrospective review. Percutaneous drainage of CSF with Rickham reservoirs was associated with a 27% rate of infection as identified by positive microbiological cultures; tunnelled ventriculostomy catheters had a 10% infection rate. The difference in the infection rate between the two methods was statistically significant (P < 0.015). Other variables examined, including the age and sex of the patients and the reasons for ventricular drainage, were not associated with an increased rate of infection. Most infections from either method were caused by a coagulase negative staphylococcus. The average duration of ventricular drainage before identification of positive cultures was 5.7 days for Rickham reservoirs and 6.0 days for ventriculostomies.  相似文献   

13.
鲁迅先生一生热爱美术作品,对版画中木刻兴趣尤甚.<野草>作为其"写心之作",亦呈现出一些与木刻版画一致的审美特征:一是具有木刻版画的色彩特征,多对比、多冷色,有阴郁的美感;二是具有木刻版画的力度特征,环境描写、人物刻画处处刀锋毕现,遒劲有力,有一种"力之美".  相似文献   

14.
张兴强  叶运福 《冶金设备》2005,(6):71-72,47
针对四辊破碎机车刀架车削中存在的几个问题,详细介绍了电动车刀架的结构和工作原理,建立主要设计参数的数学表达式,并进行适当的分析。改造后,这种电动车刀架运行平稳、可靠、方便、省力,取得了预期的效果。  相似文献   

15.
转炉炉壳热应力分析   总被引:5,自引:1,他引:4  
任学平  郭志强  邹家祥 《炼钢》2001,17(6):47-49
根据实际转炉建立实体模型。以有限元为手段,考虑了炉衬和炉壳材料的物性参数随温度变化的特点和炉衬与炉壳之间膨胀间隙,计算了转炉炉壳在温度载荷和炉衬膨胀压力同时作用下的热应力。所得结果可为转炉炉壳设计提供依据。  相似文献   

16.
In this paper is treated the fundamental problematic of the fracture of the diaphysis of the tibia and the therapeutic results after the conservative and operative treatment are confronted. Among 518 patients with 433 open fractures and 35 with closed fractures of the diaphysis of the tibia, successful treatment of more 2/3 was obtained in the period from 1968 to 1972. Following our casuistics and literature, whose results are similar, we find out that the average total treatment of the osteosynthesis of the fracture of the diaphysis was shortened for 2,5 months depending upon the type and the localisation of the fracture. Apolied methods of the operative and conservative and conservative treatment in relation to the velocity of the medical cure as well as to the extreme anatomical-functional results are analised. We noticed that osteosynthesis, made by the intermedullary nail and the extension of the canals or by a small AO table, by the achieved stability makes conditions of immediate motions and an early rehabilitation. Because of that it gives the best functional results.  相似文献   

17.
18.
Cancer of the cardia is traditionally discussed with cardiac cancer of the lower portion of the esophagus and upper gastric cancer invading the esophagus, and the specific characteristics of cancer of the cardia have never been clearly defined. We reviewed the outcome of 172 patients with adenocarcinoma of the cardia who had undergone radical surgery between 1949 and 1994 in the Division of Gastrointestinal Surgery of the Cancer Institute Hospital. The centers of the tumors were located within 2 cm above and below the boundary between the esophagus and the stomach, and their longitudinal diameter was less than 8 cm. We divided the patients into an early period (1949-1979; n = 79) and a late period (1980-1994; n = 93), and focused on the historical transition. There were no differences in patient gender or histology between the two periods. However, the late period was associated with fewer cases of esophageal invasion and shorter longitudinal diameter, as the age of the population advanced. The number of advanced cancers such as the localized and infiltrative type had decreased, and early cancer and early clinical stage had become more common, but despite the fact that the number of early cancers had increased, extended dissection, such as thoracic and paraaortic lymph node dissection, was performed more frequently. By clinical stage, the long-term outcome markedly improved in Stage I patient in the late period, and tended to improve in Stage II and III patients. This appears to have been attributable to the prevention of micrometastasis by extended dissection, although the number of early cancers is another major potential cause. There were no differences in the outcome of Stage IV patients between the two periods, and further advances in multimodality therapy must be awaited. The range of resection is basically proximal gastrectomy, and if there are adequate indications, the prognosis is favorable. In view of the status of lymphatic flow and lymph node metastasis, and long-term results, lateroaortic lymph node dissection is important. Since the number of early cancer patients has been increasing, if intraabdominal recurrence is prevented, intrathoracic lymph node dissection will contribute greatly to the outcome of such patients.  相似文献   

19.
通过对焦炭在高炉内的历程及其变化规律的剖析,阐述焦炭热性能指标的意义,形象地把焦炭在高炉内的损耗分为三部分(M1,M2,M3)。指出M2对焦比及焦炭价格有一定的指导作用。  相似文献   

20.
为了编制实用性强的基地建设行动方案,首先,确定参与式发展的主体,搭建一个"决策框架";其次,针对行动目标,提出不同参与主体,如管理者、农民、消费者等团队与个人的目标及行动内容;最后,工作应向重塑伙伴式合作关系,挖掘农民自我发展潜力,完成三大角色的转换,打造农业基地文化等方向推进.  相似文献   

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