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1.
[目的]研究大豆异黄酮微波法的最佳提取工艺.[方法]采用正交试验,以异黄酮含量为考察指标,对影响大豆异黄酮微波法提取工艺的因素进行了研究.[结果]大豆异黄酮微波提取法最佳工艺为:料液比1:30,微波功率640 W,微波时间3 min,在70℃水浴浸提40 min.[结论]微波提取具有提取率高、速度快、耗能低等特点,用于大豆异黄酮的提取,工艺简单、合理,应用前景广阔.  相似文献   

2.
[目的]优化川楝子中川楝素溶剂回流提取法的最佳提取工艺.[方法]采用HPLC法检测,以川楝素含量作为指标,考察提取溶剂、料液比、提取温度、提取时间、提取次数对川楝素提取率的影响,筛选出最佳的提取工艺.[结果]溶剂回流法的最佳条件:以甲醇为溶剂,料液比为1:30,提取温度为80℃,提取时间为1.0 h,提取次数为2次.在最佳工艺条件下,川楝素提取率达1.344 9 mg/g.[结论]该工艺简单、稳定、可行,为川楝素的提取提供了一种有效的方法.  相似文献   

3.
[目的]为有效开发利用药材资源肉苁蓉提供参考.[方法]采用索氏提取法提取沙漠肉苁蓉肉质茎中主要活性成分苯乙醇苷类,通过4因素3水平的正交试验,结合紫外分光光度法,确定苯乙醇苷类的最佳提取工艺.[结果]影响内苁蓉中苯乙醇苷类得率的主要因素是提取时间,各因素影响顺序为提取时间>粉碎度>乙醇用量>乙醇浓度.苯乙醇苷类的最佳提取工艺为20倍体积的质量分数95%乙醇回流提取肉苁蓉粉末1 h.[结论]该提取方法提取沙漠肉苁蓉中的苯乙醇苷类得率高,稳定性好,工艺可控性强.  相似文献   

4.
[目的]优化超声波辅助提取络石藤中总黄酮的工艺.[方法]以总黄酮含量为考察指标,采用正交试验设计研究超声波辅助提取络石藤总黄酮的最佳工艺条件.[结果]最佳提取工艺为乙醇浓度60%、反应温度70 ℃、超声时间30 min、料液比1:15;在此条件下,总黄酮的提取率为3.22%.[结论]优化后的工艺简便可行,可为络石藤总黄酮提取纯化工艺的产业化提供理论依据.  相似文献   

5.
[目的]提取桑叶多糖并进行含量测定.[方法]采用氢氧化钠提取桑叶中的多糖,从浸提浓度、提取温度、提取时间、料液比4个方面对提取率进行了分析,通过正交试验筛选出碱性提取的最佳工艺条件,得出桑叶多糖氢氧化钠提取的最佳条件.用苯酚-硫酸法测定多糖的含量[结果]单因素试验得出的最佳条件是提取液浓度为0.5 mol/L,提取温度为80℃,料液比为1:50,提取时间为4 h.正交试验筛选出桑叶中多糖提取的最佳条件是浸提浓度为1.5 mol/L,提取温度为80℃,料液比为1:50,提取时间为4 h,多糖含量为2.55%.[结论]提取时间对桑叶多糖的提取有比较大的影响,在单因素试验的基础上通过正交试验得出最佳配比,使得提取更加充分.  相似文献   

6.
[目的]优化牛蒡抗氧化成分的提取工艺,并对其抗氧化性能进行测定.[方法]采用正交试验对其提取工艺进行优化:采用常规方法测定牛蒡提取物对超氧阴离子自由基和羟基自由基的清除率.[结果]牛蒡抗氧化成分最佳提取工艺条件为:料液比1:20,乙醇浓度100%,提取时间为1.5 h,提取温度70℃.牛蒡提取液清除超氧阴离子自由基和羟基自由基的能力随着浓度的增加而增强,且牛蒡乙醇提取液清除自由基能力强于牛蒡水提液.牛蒡提取液的主要成分为绿原酸.[结论]该研究为牛蒡提取物在食品和医药行业的应用提供了科学依据.  相似文献   

7.
[目的]优化银杏叶总黄酮的提取工艺,为银杏黄酮的精制提供前提条件.[方法]采用紫外分光光度法测定银杏叶中总黄酮的含量;用单因素试验考察乙醇浓度、回流温度、提取时间对银杏黄酮收率的影响,优化提取条件.[结果]银杏叶中总黄酮含量为1.502 6mg/ml;最佳提取条件:70%乙醇为提取剂,回流温度为80℃,提取时间为3.0 h.[结论]该研究得到银杏黄酮最佳的提取工艺,为银杏叶黄酮的精制提供了前提条件.  相似文献   

8.
[目的]建立新的芦荟活性成分提取方法.[方法]采用超声波萃取技术对芦荟活性成分进行提取,对超声波萃取工艺中料液比、萃取温度、超声波萃取时间、超声波功率进行了正交试验优化.[结果]得到超声波萃取芦荟活性成分的最佳工艺条件:料液比1:1.0,萃取温度30℃,萃取时间4 h,超声波功率490W.[结论]超声波辅助萃取法具有时间短、温度低、节省溶剂、萃取油质量高等优点,用于提取芦荟活性成分是可行的.  相似文献   

9.
[目的]对紫色杂交水稻米糠油的提取条件进行探索,并分析其脂肪酸成分组成情况.[方法]采用索氏抽提法提取紫色杂交水稻米糠油,甲酯化后运用GC-MS分析其脂肪酸组分,与II优725杂交水稻米糠油、花生油和菜籽油成分比较后利用DPS软件进行聚类分析.[结果]紫色杂交水稻米糠油最佳提取条件为:粉碎度50目,米糠含水量8%,料液比1:5;采用2次脱色工艺,快速过滤,真空度0.08 MPa,第1次白土添加量为4%,温度为90 ℃,时间为30 min;第2次白土添加量为3%,温度为80 ℃,时间为15 min.最佳脱臭条件为:真空度0.07 MPa,温度170 ℃,时间1.5 min.GC-MS共检出10种脂肪酸,其中饱和脂肪酸6种,以软脂酸、硬脂酸为主,相对含量为26.32%;不饱和脂肪酸有4种,以油酸、亚油酸为主,相对含量为67.66%.紫色杂交水稻米糠油与II优725杂交水稻米糠油成分和含量相比,不相似性约0.94%,但与花生油和菜籽油差异较大.[结论]索氏抽提法提取紫色杂交水稻米糠油可达国标3级油标准,且其营养丰富,具有很好的开发利用前景.  相似文献   

10.
[目的]探索超声波辅助提取新鲜贵州九阡李中类胡萝卜素的最佳工艺.[方法]采用超声波有机溶剂法提取贵州九阡李中类胡萝卜素,在单因素试验优化九阡李中类胡萝卜素提取条件的基础上,采用正交试验确定九阡李中类胡萝卜素的最佳提取条件,用紫外分光光度法测定类胡萝卜素含量,并计算提取率.[结果]九阡李中类胡萝卜素的最佳提取条件为:以石油醚-丙酮(2:1,V:V)作为提取剂,超声波提取20 min,料液比(M:V,g/ml)为1:10.在该条件下,九阡李中类胡萝卜素的提取率为174.0 μg/g.[结论]该研究为其他新鲜果品(尤其是李子)的研究奠定了基础.  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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