绿芦笋粉挥发油提取工艺的优化及成分分析

[目的]优化超临界CO2流体萃取技术(SC-CO2)提取绿芦笋粉挥发油的工艺,并对其化学成分进行分析,为绿芦笋粉的深入研究和综合应用奠定基础.[方法]以挥发油提取量为评价指标,设计4因素3水平正交试验优化超临界CO2萃取绿芦笋粉挥发油的工艺条件,利用GC-MS对萃取物化学成分进行分析.[结果]超临界CO2萃取绿芦笋粉挥发油的最佳条件为:CO2流量20 L/h,萃取温度35 ℃,萃取压力25 MPa,萃取时间2 h,在此条件下,绿芦笋粉挥发油的提取率达到98%;主要包括37种化合物,其中以烷类含量最高,其次是醛类和酯类.[结论]在最佳工艺条件下,SC-CO2萃取绿芦笋粉挥发油的提取率高,这为绿芦笋粉的深入研究和综合应用奠定了基础.     

南疆冬枣的营养及挥发性成分分析

[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.     

外来入侵植物假臭草挥发性成分分析

[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.     

薏米的成分分析

[目的]对市售薏米的成分进行分析,为薏米的开发利用提供参考.[方法]用常规方法测定薏米各成分含量.[结果]薏米中水分、灰分、脂肪、纤维和蛋白质的含量分别为10.73%、1.64%、5.56%、0.44%和14.26%.Zn、Fe、Ca、Mg、Cu 5种微量元素的含量分别为43.24、212.90、749.00、1 193.60、11.70 μg/g.[结论]薏米中营养成分含量丰富,这为薏米的进一步开发提供了理论根据.     

我国稀土萃取分离过程分析的现状

简介了我国稀土萃取分离过程分析的现状,对稀土分离生产线在线分析与自动化控制有一定的参考价值。     

超临界CO2萃取茶多糖的试验研究

[目的]进行超临界CO2萃取茶多糖的条件研究,确定超临界CO2萃取茶多糖的最佳萃取工艺参数,为提取茶多糖提供理论依据.[方法]使用蒽酮-硫酸法测定茶多糖含量,用超临界CO2萃取技术提取茶多糖,对茶粉颗粒度、夹带剂及夹带剂的用量、萃取压力、萃取温度、萃取时间对茶多糖提取率的影响进行单因素试验研究,获取最佳萃取工艺参数.[结果]在颗粒度为40目茶粉,20%无水乙醇夹带剂,萃取压力35 MPa,萃取温度45 ℃,萃取时间2.0 h的试验条件下,可获得最佳的茶多糖提取效果.[结论]在最佳超临界CO2萃取条件下,茶多糖提取率可达92.5%.与传统方法相比,在保持茶多糖生物活性的基础上,提高了茶多糖的提取率,为茶多糖提取提供了新的思路.     

全自动固相萃取—气质联用法对平整液废水中多环芳烃的测定

建立了固相萃取—气相色谱/质谱联用测定平整液废水体系中多种多环芳烃(PAHs)的分析方法。结果表明,用C18固相萃取柱,以二氯甲烷为洗脱剂,在上样速率为5 mL/min的条件下,用于平整液废水中多种PAHs的检测,均有较好的回收率,在5～200μg/L范围内呈良好的线性关系,相关系数>0.99,加标回收率为96%～112%,方法简便可靠且能自动化进行,能够达到对平整废水中19种多环芳烃的检测要求。     

新疆石榴籽油超临界萃取工艺条件研究

[目的]研究超临界萃取石榴籽油的最佳工艺条件.[方法]运用超临界萃取法提取新疆石榴籽油有效成分,采用GC-MS技术对萃取物化学成分进行分析,同时分析萃取压力、萃取温度、萃取时间对石榴籽油提取率的影响.[结果]最佳提取条件:萃取压力为30MPa,萃取温度为40℃,萃取时间为3 h.在此条件下石榴籽油的萃取得率为18.35%.[结论]超临界萃取石榴籽油工艺稳定可靠,具有极高的应用价值.     

火电厂 600 MW超临界机组协调控制系统的分析研究

对火电机组的控制系统进行分析比较,对600 MW超临界机组及其协调控制系统的特点进行综述.了解超临界机组运行特性;分析火电机组协调控制系统基本设计思想和设计方法.在Matlab环境下,封装控制逻辑块,搭建控制逻辑,对实际电厂600 MW超临界机组协调控制方案进行分析研究,了解火电机组协调控制系统常用方案及实现方法,对实际机组的协调控制系统进行具体的分析.     

Composition and antimalarial activity in vitro of volatile components of Lippia multiflora

The essential oil of Lippia multiflora was prepared by hydrodistillation of leaves and stalks and characterized by GC and mass spectroscopy. The oil was tested for antimalarial activity on in vitro cultures of Plasmodium falciparum (FcB1-Columbia chloroquine-resistant strain and F32-Tanzania chloroquine-sensitive strain). The dilutions inhibiting the in vitro growth of the parasite by 50% 24 and 72 hr after administration of the essential oil to the parasite culture were 1/12,000 and 1/21,000, respectively. When tested on a highly synchronized culture, the essential oil inhibited growth mostly at the trophozoite-schizont step, indicating a potential effect on the first nuclear division of the parasite.     

蝴蝶蜜源与非蜜源植物挥发物成分的差异

采用全自动热脱附-气相色谱/质谱(ATD-GC/MS)联用技术,对动态顶空密闭循环吸附捕集的蝴蝶蜜源植物马缨丹、马利筋及非蜜源植物缅栀子花的挥发物进行分析检测.结果表明,同为蝴蝶的蜜源植物,马利筋和马缨丹的挥发物成分的种类和含量都有差异.马缨丹的香气成分主要为萜烯类化合物(60%),而马利筋中醛类(33.72%)含量相对高些,烯烃含量约占11%,二者都含有少量的醇.作为蝴蝶的非蜜源植物,缅栀子花的挥发物中有一定量的肟类(24.99%)和腈类(5.34%),在马利筋和马缨丹中均未检测出这2种组分.     

Estimation of escape rate of volatile components from slags containing CaF2 during viscosity measurement

In continuous casting process, the viscosity of the mould powder/flux has direct impact on the size of the gap between the mould wall and the solidified shell, which in turn affect the heat transfer characteristics between the metal and the mould. Numerous experiments have been conducted to determine the viscosity of various mould powders using rotation cylinder method. The pre-melting of the mould powder as well as the viscosity measurement are carried out in a cylindrical crucible placed in a tubular furnace with constant argon flow to maintain inert atmosphere. One of the main difficulties encountered during viscosity measurement is the liberation of volatile fluorides, which in turn changes the flux composition, and consequently the viscosity of the flux. Thermodynamic calculations have shown that SiF₄ and HF are major constituents of the volatile matter. Present study aims to estimate the liberation rate of SiF₄ and HF from flux samples during viscosity measurement by computing the detailed gas flow pattern inside the tubular furnace. The gas flow pattern is computed by solving momentum and continuity of equations. Further, the effect of argon gas flow rate and slag level in the crucible on liberation rate has been studied to arrive at proper experimental conditions during viscosity measurement.     

熔融制样-X射线荧光光谱法测定黑刚玉中6种组分

黑刚玉是一种以Al2O3、SiO2和TiO2为主要成分的新型环保材料,其化学成分的分析一般采用滴定法、分光光度法或原子吸收光谱法等,这些方法操作相对繁琐、流程长.实验采用H3BO3-Li2CO3混合熔剂(m∶m=7∶3)按质量比为1∶10的稀释比进行熔融制样,加入0.15 g NH4I脱模剂,有效地消除了矿物效应、粒度...     

Analysis and identification of calculus equi components

Components of the genuine calculus Equi and false Mabao were analyzed by X-ray diffraction. The results indicate that the main components of the genuine Mabo are NH4MgPO4.6H2O, NH4MgPO4.H2O and MgHPO4.3H2O, whereas the main components of the false Mabao is CaCO3.     

熔融制样-X射线荧光光谱法测定珊瑚礁样品中15种主次和微量组分

珊瑚礁样品中SiO₂、Al₂O₃、Fe₂O₃、Na₂O、K₂O、MnO、TiO₂和P₂O₅等低含量组分的测试通常需要采用不同的方法和仪器,难以满足批量样品测试的需求。实验以Li₂B₄O₇-LiBO₂-LiF为熔剂,采用高温熔融制样,建立X射线荧光光谱法(XRF)测定珊瑚礁样品中SiO₂、Al₂O₃、Fe₂O₃、MgO、CaO、Na₂O、K₂O、MnO、TiO₂、P₂O₅、SO₃、Sr、Zr、Ba和Cr含量的方法。对熔融制样条件进行了优化,其中脱模剂LiBr饱和溶液最佳用量为150 μL。选取岩石、碳酸盐岩石、水系沉积物国家标准物质以及在标准物质中加入Sr标准溶液的方式建立校准样品系列,Sr和Zr采用经验系数法和康普顿散射线内标法校正基体效应,其他组分采用理论α系数校正基体效应,有效克服了基体效应的影响。结果表明,各组分测定值的相对标准偏差(RSD,n=7)为0.25%～19.5%。方法用于珊瑚礁实际样品分析,其分析结果与采用化学湿法的测定结果吻合,各组分的相对误差绝对值为0～28.86%。     

Determination of major volatile components in suhexiang wan (storax pill) using analytical supercritical fluid extraction (SFE)

A new method based on the off-line coupling of analytical SFE and GC has been developed for qualitative and quantitative analysis of major volatile components in Suhexiang Wan, a Chinese patent medicine. The factors affecting extraction efficiency were examined to seek the optimal operating parameters. Quantitative recovery (90%) was achieved with 20 ml CO2 in ca 1 h using a self-designed analytical SFE system. Compared with the conventional methods, the SFE as an alternative technique for sample preparation will be most useful in the quality control of Chinese patent medicine.     

黑色岩系样品中铂族元素的分析方法

近年来发现,不同地质时代的黑色岩系都可能含有贵金属矿物,但其分析测试结果的重现性很差,即"若有若无",严重影响地质研究工作的进展.根据黑色岩系样品的成分特征,对常规测定铂族元素的锍试金配方做了改进,增加了具有还原性的覆盖剂,且无需加入Os同位素稀释剂.通过实验选择了合适比例的试金配料,熔融后获得的镍扣直接用水浸泡粉化后...     

Analysis of the properties and functions of metal components

The properties of a metal component are analyzed and classified. It is established that the structure of the properties of some object may be described in terms of the determination of functions at different levels. The properties of metal components are analyzed and, on that basis, the concept of a function is defined. The concept of a component’s useful phase is introduced on the basis of the functional principle of property analysis. A design definition of the quality of metal products is proposed: the quality is the degree of fulfillment of three functions—transportation, installation, and operation. The methods of quality analysis based on investigation of the functions of the product over the duration of its useful phase also constitute the essence of functional–goal analysis. On the basis of this approach, the algorithm for quantitative quality assessment is improved. In the proposed approach, the stages of the life cycle are specified; the functions are arranged in a multilevel structure; and a single material body is regarded as a system of properties that will be differently expressed, depending on the purpose for which it is employed. Accordingly, functional–target analysis may be regarded as a new approach to studying the structure of the functions and properties of a metal component.     

大豆荚壳营养成分分析与评价

为了解大豆荚壳中的营养成分,以大豆荚壳为原料,对大豆荚壳中的主要营养成分进行了测定.结果表明,大豆荚壳中含有总黄酮、蛋白质、还原糖、总糖、粗纤维、粗脂肪和灰分等多种营养成分,含量分别为8.49%、4.39%、2.23%、5.05%、7.32%、32.22%、5.28%.大豆荚壳所舍的17种氨基酸中,人体必需氨基酸占氨基酸总量的42.01%.针对大豆荚壳的营养特点,可以进行不同产品的开发.