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1.
基于阿拉山口口岸重要地理位置,结合进口中亚铜矿和含铜物料情况,按照国别收集阿拉山口口岸进口铜矿和含铜物料样品。利用红外光谱可根据未知物在红外光谱中吸收峰的强度、位置和形状,确定该未知物分子中包含有哪些基团,从而推断该未知物的结构的性质,通过优化实验条件,对铜矿和含铜物料进行定性鉴定技术的研究,并建立符合新疆口岸进口中亚国家铜矿产品谱图库,便于快速确定矿产国别及品质源头,防止低含量铜冶炼残渣易名高含量铜精矿进口,危害国家利益。  相似文献   

2.
基于阿拉山口口岸重要地理位置,结合进口中亚铜矿和含铜物料情况,按照国别收集阿拉山口口岸进口铜矿和含铜物料样品。利用红外吸收光谱可根据未知物在红外吸收光谱中吸收峰的强度、位置和形状,确定该未知物分子中包含有哪些基团,从而推断该未知物结构的性质,通过优化实验条件,对铜矿和含铜物料进行定性鉴定技术的研究,并建立符合新疆口岸进口中亚国家铜矿产品谱图库,便于快速确定矿产国别及品质源头,防止低含量铜冶炼残渣易名高含量铜精矿进口,危害国家利益。  相似文献   

3.
本文提出了分段式离子系列谱编码方法,实验证明具有很好的结构表征能力。本程序主要是以模式识别技术为基础,实现了对未知物谱图的KNN分类,进而得到未知物的主要结构特征。这个程序应用于有机化合物的分类,取得了满意的结果。  相似文献   

4.
用傅里叶变换红外光谱差谱技术分析香烟添加剂   总被引:1,自引:0,他引:1  
郑爱华  杨耿 《分析化学》1998,26(2):245-245
1引言用傅里叶变换红外光谱(FTIR)差谱技术研究分子变化报道较多,但应用于分析未知物组成尚未见报道。未知物组成复杂,为了使差谱运算简单化,本文采用微量加样涂膜法制样,在近8μm厚度下,保证了谱带尖锐和实验重复性,无需溶剂稀释样品;用普通可拆液体池代替固定液体池,可方便地拆洗;从直观的差谱屏幕上,仔细考察差谱过程中谱峰变化,进行谱带归属,以获得未知物结构组成的定性、定量红外信息。应用差谱技术分析香烟添加剂,可不需分离,快速给出定性、定量结果。2实验与结果2.1仪器与试剂FTS-40型FTIR光谱…  相似文献   

5.
通过红外光谱(IR)、能谱(EDS)、液质联用(LC-MS)以及核磁共振(NMR)等现代仪器分析技术,对一种黄色未知物进行结构鉴定,确认未知物的结构为2-甲氧基-4-吗啉基重氮苯氯化锌盐。  相似文献   

6.
介绍一个综合化学实验,主要内容为用三氯化铁和草酸钾为原料水相制备三草酸合铁(Ⅲ)酸钾并对其结构进行表征。测定了配合物的组成和配离子电荷,重点研究了配体和配合物的电子光谱和红外光谱,测定了配合物的磁矩、XRD和热稳定性等。实验结果表明,制得的配合物组成为K3[Fe(C2O4)3]·3H2O,产率90.0%;电子光谱吸收峰数值小于350~400 nm,是由配体到中心离子的电子跃迁产生的;红外光谱归属推断配合物中存在双齿或螯合的草酸根;配合物磁矩为5.16 B.M.,中心离子Fe3+的杂化态为sp3d2,配合物为高自旋的外轨配合物,八面体结构。通过该实验,学生能够理解配合物制备、组成测定和结构表征系列实验的原理,熟悉各种现代测试技术,激发学生对科学研究的兴趣,培养学生综合实验能力和创新能力。  相似文献   

7.
《大学化学》2006,21(6):60-62
一、实验目的 (1)掌握凝固点降低法测定物质的摩尔质量的基本原理与实验技术. (2)测定水的凝固点降低值,计算未知物的摩尔质量.  相似文献   

8.
熊玥  汪澄  刘建晖  石慧慧  汪云花  孙瑶  于洁 《色谱》2021,39(6):633-641
应用非靶向分析技术,筛查、分析和确证恩诺沙星粉(水产用)中的非法添加物。分别制备甲酸酸化、碳酸钠碱化的恩诺沙星粉供试品溶液,经超高效液相色谱-二极管阵列检测器(UPLC-PDA)检测初筛,获取未知物色谱图。应用超高效液相色谱-飞行时间高分辨质谱(UPLC-TOF-HRMS),在正、负离子模式下对酸化、碱化样液进一步检测,获得未知物母离子和二级特征碎片的精确质荷比、同位素信息,并应用SCIEX OS软件进行分析推导。最后取疑似化合物对照品进行确证研究。UPLC-PDA初筛结果显示:酸化样液在1.870 min、5.122 min,碱化样液在5.122 min,均发现高响应未知色谱峰。对吸收波长和峰面积进行分析,推测含2个未知物,且未知物1(1.870 min)与未知物2(5.122 min)在酸性/碱性条件下可能发生转换。SCIEX OS软件分析推导结果显示:未知物2,母离子分子式拟合为C11H8O2,二级碎片结构解析含1个苯环、2个羰基和1个通过成环连接的丙烯结构,推测为甲萘醌;未知物1的分子离子峰为C11H9O5S-,二级碎片仅采集到HSO3-,丢失部分与未知物2一致,结合甲萘醌常见衍生物类型,推测为亚硫酸氢钠甲萘醌。取甲萘醌、亚硫酸氢钠甲萘醌对照品进行对比研究,UPLC-PDA检测结果显示:未知物1与亚硫酸氢钠甲萘醌、未知物2与甲萘醌,保留时间和紫外光谱一致;向供试溶液中添加对照品溶液后检测,未知物为单一峰。UPLC-TOF-HRMS检测发现:未知物1与亚硫酸氢钠甲萘醌保留时间一致,一级质谱质量偏差为1.0×10-6,二级谱库匹配度为100%;未知物2与甲萘醌保留时间一致,一级质谱质量偏差为0.6×10-6,二级谱库匹配度为99.7%。未知物1和2的结构得以确证。亚硫酸氢钠甲萘醌可止血,与恩诺沙星治疗败血症的适应证相应,佐证试验结果。随着对兽药非法添加行为的严格监管和严厉打击,非法添加物和添加手段愈发隐蔽,常规靶向分析难以满足监控需求。该文详述的使用UPLC-PDA结合UPLC-TOF-HRMS对未知物进行非靶向分析的技术,可为药品、食品、保健品、化妆品及农药等产品中非法添加物的筛查和确证提供思路和技术参考。  相似文献   

9.
一般说来,推断题分为元素推断题和物质推断题两种类型。下面就这种题型的内容和特点以及解题规律进行探究。一、元素推断题的解题规律元素推断题是指根据题目给出的条件进行未知元素推断的题型。  相似文献   

10.
合成了八个新型的三甲基镓与侧链含酚羟基的氮杂冠醚所生成的配合物,用元素分析、红外、核磁共振和质谱的方法进行了表征,推断了它们的结构。配合物结构的研究对于探讨MO新源的MOCVD技术研究具有重要意义  相似文献   

11.
The spectral-polarization characteristics of absorption and phosphorescence of molecules of the initial form of nitro-substituted indolinospirobenzothiopyran were studied in oriented polyethylene films and in solutions with different polarity. An oscillator model of the electron transitions responsible for the formation of absorption and luminescence spectra was suggested. It was established that the principal differences in the spectral and photophysical properties of the compound studied and its oxygen-containing analog are associated with the fact that the electronegativity of the S atom is lower than that of the O atom. Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 6, pp. 1143–1146, June, 1997.  相似文献   

12.
非那雄胺能抑制5α-还原酶的活性,明显降低二氢睾酮水平,是一种治疗良性前列腺增生的有效药品。该合成工艺以甾烯酮酸为原料,将其与氯化亚砜反应,无须分离即与叔丁胺反应得17β-酰胺化合物,再氧化开环,环合,氢化,脱氢合成了非那雄胺。经元素分析、IR、1HNMR、13CNMR、MS分析表征了其结构。该法无须使用昂贵的2,2-二吡啶二硫化物和剧毒药品苯亚硒酸酐,且以乙酸铵代替氨气,降低了对设备的要求和腐蚀,更适用于工业生产。  相似文献   

13.

The heats of detonation of 20 simple high explosives and explosive mixtures were determined by means of an adiabatic detonation calorimeter designed by the authors. The results indicated that the performance of the instrument was reliable and the experimental data were very accurate. For explosive mixtures, there was a linear accumulative relationship between the heats of detonation of the explosive mixture and its components. Accordingly, the heats of detonation of explosive mixtures could be calculated directly from the heats of detonation of simple explosives and the characteristic heats of other components. The experiments showed that the gold or brass shell of the cylindrical charge could be substituted by a thick-walled porcelain shell, which had the advantage of cheapness.

  相似文献   

14.
Two vanilloids, (5E)-8-(4-hydroxy-3-methoxyphenyl)oct-5-en-4-one (1) and 4-[3-hydroxydecyl]-2-methoxyphenol (2), isolated from the dried seeds of Grains of Paradise (Aframomum melegueta), were synthesized; the latter compound was made as the S-enantiomer and the material derived from the seeds was found to be a 1:1.7 mixture of the R and S isomers. The synthetic route used should allow the preparation of analogs having extended alkyl chains and consequently different lipophilicity, and 3, a homolog of 2, was also prepared.  相似文献   

15.
针对恶臭测试的环境影响问题,提出了解决的实例方案,并对方案的要点及优缺点进行讨论,此方案在实际操作中具有较好的效果。  相似文献   

16.
翟宗玺  刘树深  夏树屏 《化学学报》1990,48(10):946-950
用氧化镁氯化镁水溶液制备了8水合氯氧化镁[nMg(OH)2·MgCl2·8H2O], 并测定了其在盐酸中的溶解热, 实验结果表明, 氯氧化镁溶解热与n值呈线性关系, 根据溶解热求出5Mg(OH)2·MgCl2·8H2O和3Mg(OH)2·MgCl2·8H2O的生成热分别为-7727.1和5888.1kJ·mol^1^-。  相似文献   

17.
In this review, the research of the author in the field of colloidal systems is summarized. The factors influencing colloidal stability are systematized and analyzed. Examples are presented to illustrate the practical utilization of the theory of stability of colloids and thin films.This review was prepared on the basis of the works of the author, which were awarded the State Premium for 1991 in the field of science and technology, chemistry section.Institute of Physical Chemistry, Russian Academy of Sciences, 117915 Moscow. Translated from Izvestiya Akademii Nauk, Seriya Khimicheskaya, No. 8, pp. 1708–1717, August, 1992.  相似文献   

18.
Main hydration products of two cement pastes, i.e. CSH-gel, portlandite (P) (and specific surface S) were studied by static heating, and by SEM, TEM and XRD, as a function of cement strength (C-33 and C-43) hydration time (th) and subsequent hydration in water vapour.Total change in mass on hydration and air drying, Mo, increased with strength of cement paste and with hydration time. Content of water escaping at 110 to 220°C, defined as water bound with low energy, mainly interlayer and hydrate water, was independent on cement strength but its content increased with (th). Content of chemically bound (zeolitic) water in CSH-gel, escaping at 220-400°C, was slightly dependent on strength and increased with (th). It was possibly derived from the dehydroxylation of CSH-gel and AFm phase. Portlandite water, escaping at 400-500°C, was independent on cement strength and was higher on longer hydration. Large P crystals were formed in the weaker cement paste C-33. Smaller crystals were formed in C-43 but they increased with (th). Carbonate formated on contact with air (calcite, vaterite and aragonite), decomposed in cement at 600-700oC. It was high in pastes C-33(1 month) and C-43(1 month), i.e. 5.7 and 3.3%, respectively; it was less than 1% after 6 hydration months (low sensitivity to carbonation) in agreement with the XRD study showing carbonates in the air dry paste (1month), and its absence on prolonged hydration (6 months) and on acetone treatment. Water vapour treatment of (6 months) pastes or wetting-drying increased this sensitivity.Nanosized P-crystals, detected by TEM, could contribute to the cement strength; carbonate was observed on the rims of gel clusters.This revised version was published online in November 2005 with corrections to the Cover Date.  相似文献   

19.
袁丽秋 《化学教育》2006,27(5):8-10
面对日益枯竭的能源危机,氢能是一种洁净、最有前景的替代能源。目前在各种制氢的方法中光催化分解水制氢的研究最多,光解水过程中催化剂最关键,本文对利用太阳能光解水的途径、提高光催化反应效率以及光催化剂的开发研究进行了综述。  相似文献   

20.
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