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1.
内蒙古地区沙生植物--沙枣对亚硝酸盐分解作用的研究   总被引:2,自引:0,他引:2  
利用分光光度法研究了内蒙古地区沙生植物———沙枣对亚硝酸盐的分解作用。结果表明,沙枣中富含的维生素C、维生素E和脯氨酸等抗氧化剂可以作为还原剂与亚硝酸盐作用,从而降低亚硝酸盐的含量;加入的沙枣量愈多,随时间延长对亚硝酸盐的分解能力亦增强,但不呈线性关系。试验结果表明,沙枣不仅可以作水土保持、防沙造林的先锋树种,还由于它富含抗氧化物,可作为人体降低体内亚硝胺生成的良好补充源。  相似文献   

2.
在 pH 6.0的 HAc-NaAc缓冲溶液中,用活性炭吸附沙枣中的色素,Cu(Ⅱ)催化氧化维生素C,在λmax=268 nm处可直接测定沙枣中维生素C含量.与传统碘量法相比,测定结果基本一致.为内蒙古地区沙枣天然植物资源的药用开发、食品加工等提供了参考数据.  相似文献   

3.
以内蒙古地区沙棘果实为原料,研究了提取黄色素的工艺条件,同时对该色素的性质进行了初步探讨。结果表明,以95%的乙醇溶液作浸提剂,提取的黄色素浓度最高,工艺流程简单易行,且无毒,无污染。对提取的黄色素进行的性质试验表明,沙棘黄色素对光、热具有较好的稳定性,适用于酸性或弱碱性的食品中,葡萄糖、氧化剂(H2O2)、还原剂(Na2SO3)等食品添加剂均无明显影响以上结果为这种优良天然色素的开发与应用提供了参考。  相似文献   

4.
胡勇  黄鹂 《化学教育》2006,27(2):56-58
就植物酸碱指示剂材料的筛选,植物色素提取液的稳定性,色素晶体的提取,色素临时提取液的变色情况测试,色素提取液测酸雨等方面进行研究,旨在学会科学研究的方法。  相似文献   

5.
1,2,4--三唑衍生物的合成及植物生长调节活性的研究   总被引:1,自引:0,他引:1  
合成十五个新的三唑衍生物,通过1HNMR、IR、EA确证了它们的结构。生物测定显示:有些化合物有良好的植物生长调节活性,对水稻、黄瓜的根系伸长有很好的促进作用。  相似文献   

6.
Two novel organic amide alkaloids, 4‐[(E)‐p‐coumaroylamino]butan‐1‐ol ( 1 ) and 4‐[(Z)‐p‐coumaroylamino]butan‐1‐ol ( 2 ), together with a rare pyridoindole alkaloid, hippophamide ( 3 ), were isolated from the seed residue of Hippophae rhamnoides Linn . subsp. sinensis Rousi . Their structures were determined by spectroscopic means. The results show that compounds 1 and 2 are (E/Z)isomers, compound 3 , a pyridoindole alkaloid concerted with γ‐lactam ring.  相似文献   

7.
以波谱分析为主要手段研究沙棘果多糖Hn的结构,GC分析表明Hn由Ara,Gal,Man和Glc组成,单糖物质的量比与利用GC分析Hn甲基化产物的结果一致.^13C—NMR分析表明Hn中存在α,β型糖苷键.利用GC—MS分析进一步确定Hn主链结构由β(1→4)Glc,β(1→6)Man和β(1→4)Gal构成,在3-O处有分支,支链由α(1→4)Glc,(1→6)Gal或末端Ara,Glc构成.  相似文献   

8.
建立了一种利用2-(11-H-苯-a-咔唑)乙基对甲苯磺酸酯(BCETS)作为柱前荧光标记试剂的高灵敏度和高选择性的脂肪酸定量分析方法,并考察了该方法的分析性能。结果表明,方法表现出了较好的重现性和加标回收率,检测限在0.42~1.82ng/mL之间。该方法已被成功的用于青藏高原沙棘种子中脂肪酸含量的分析,结果表明沙棘种子中富含脂肪酸,以不饱和脂肪酸为主,约占总脂肪酸的85.01%。不饱和脂肪酸中,以油酸、亚油酸和亚麻酸为主,分别占总脂肪酸的26.01%、30.86%和14.07%。  相似文献   

9.
通过对内蒙古中部渣尔泰山群各层位岩石采样,对该山群中共43个微量元素(含稀土元素)与地壳丰度进行了对比分析,总结了该山群微量元素的地球化学特征。研究表明,该山群富集W、Re、Cu、Pb、Co等元素,而In、V、Cr、Ni等元素亏损较严重;微量元素在板岩和云母石英片岩中相对含量较高,在灰岩中相对贫化;此外,该山群稀土元素地球化学特征表现为轻稀土富集,重稀土亏损;具有明显的Eu的负异常,Ce的弱正异常。  相似文献   

10.
优化了顶空-固相微萃取法(HS-SPME)提取沙棘挥发性成分的条件,并采用气相色谱-质谱联用技术(GC-MS)分别对HS-SPME法和水蒸气蒸馏法(SD)的提取物进行分析。结果显示,在萃取温度为70℃,萃取时间为50 min,解吸时间为7 min,平衡时间为20 min条件下,HS-SPME法鉴定出76种组分,占挥发性物质总量的90.19%,主要成分为酯类、醛类和酮类;而SD法提取物共鉴定出56种组分,占挥发性物质总量的91.98%,主要成分为酯类。2种方法共有组分为20种。两种方法提取的沙棘挥发油组分的种类及含量差异较大,HS-SPME法更适合沙棘挥发性组分的快速检测。  相似文献   

11.
环境中的钒及其对人体健康的影响   总被引:6,自引:1,他引:6  
环境中的钒有多种不同来源,人类活动,尤其是大量化石燃料的燃烧,使环境中钒含量急剧增加。大气、水、土壤中的钒可通过呼吸、饮水、食物等途径进入人体,直接或间接对人体健康造成影响。目前,对钒致病的机理并无定论,仍有待进一步研究。在部分地区,有数据显示,环境中钒含量与某些癌症死亡率存在相关性。  相似文献   

12.
Abstract

A survey was carried out in the city of Brno, Czech Republic in order to determine the levels and sources of soil and plant contamination and the possible implications for human health. A group of 136 topsoil and plant samples were taken in a defined sampling pattern, both in urban (in the year 1991) and suburban (1992) areas, paying particular attention to traffic density and intensity of land use. Samples were analysed for the contents of six heavy metals (Cd, Cu, Cr, Ni, Pb, Zn) and polycyclic aromatic hydrocarbons. The main soil characteristics were also determined (pH, CEC, Cox).

Traffic influence indices (TII) were calculated for each locality based on the traffic density and micro climatic conditions. Soil pollution indices (SPI) and plant pollution indices (PPI) were defined as a loading of a group of toxic metals relative to acceptable upper limits and were used as a general measure of the soil and plant burden at a particular site.

There were significant differences between the level of pollution in urban and suburban areas particularly for Pb, Cr and Ni in plants.

Traffic was found to be the major source of pollution by Pb, Zn and Cu in the urban survey and significant correlations were found between soil Pb × TII and SPI × TII in urban area. No such relationships were found for the suburban samples.  相似文献   

13.
为了解芝罘湾沉积物中重金属的污染状况,于2009年7月采集了黄海芝罘湾16个站位的表层沉积物并测定了其中的重金属含量.芝罘湾的重金属污染程度较低,所有测定值均低于国家海洋沉积物Ⅰ类质量标准.Hg、Cu、Pb、Cd、Zn、Ni、Co、Mn 8种重金属的平均含量分别为0.02、12.3、8.67、0.13、32.8、11....  相似文献   

14.
《Analytical letters》2012,45(9):1347-1361
Abstract

A method is presented for the highly sensitive, selective, and rapid determination of vanadium (V) at sub-microgram levels in rocks, animal tissues, plant tissues and natural waters. The method is based on the selective extraction of vanadium (V) from strongly acidic (3-8 M hydrochloric acid) medium with solution of N-p-methoxyphenyl-2-furylacrylohydroxamic acid (MFHA) in chloroform. The reddish-violet extract (molar absorbance 8.6x103 1 mole?1 cm?1 at λ max 545 nm) is then equilibrated with 3-(o-carboxyphenyl)-1-phenyltriazine-N-oxide (CPPTNO) at pH = 1.5. The resulting ternary complex has enhanced colour (molar absorbance 1.4 × 104 1 mole?1 cm?1 at Λ max 450 nm). The ternary system obeys Beer's Law at 450 nm over the range 0-18 μ g/ml of vanadium. The extraction system achieves 20-fold enrichment of vanadium and enables the determination of the metal down to parts per billion (ng 1?1) levels. The method tolerates the presence of a large number of anions and cations which are normally present with vanadium in rocks, plant tissues, animal tissues and natural waters. The applicability of the method was tested by the analysis of vanadium in these matrices. MFHA was selected from nine hydroxamic acids as it provided maximum sensitivity and selectivity.  相似文献   

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