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1.
研究了一种同时测定2-氨基萘-6-磺酰甲胺及其杂质(2-氨基萘,2-乙酰氨基萘-6磺酸,2-氨基萘-6-磺酸和2-乙酰氨基萘-6-磺酰甲胺)含量的高效液相色谱法。采用HypersilBDS C18色谱柱,0.2%四丁基铵高氯酸盐(TBAPC)/乙腈/36%乙酸(60:38:2,V/V/V)为流动相,柱温30℃,在流速为1mL/min时,上述5种物质在20min内实现了基线分离。本方法快速、准确,适  相似文献   

2.
用二维核磁共振谱(COSY、HMQC、HMBC、FG_HMBC)进一步研究了2,2′-二羟基-1,1′-联萘(1)、2,2′-二甲氧基-1,1′-联萘(2)、2,2′-亚甲二氧基-1,1′-联萘(3)、2,2′-亚乙二氧基-1,1′-联萘(4)、2-羟基-2′-甲氧基-1,1′-联萘(5)、2-羟基-2′-乙氧基-1,1′-联萘(6)、2-羟基-2′-异丙氧基-1,1′-联萘(7)、2-羟基-2′-丁氧基-1,1′-联萘(8)和2-羟基-2′-氧乙酸基-1,1′-联萘(9)等9个2,2′-二取代-1,1′-联萘化合物,确定了它们的氢谱和碳谱谱峰的归属,指出联萘化合物的立体结构、萘环的磁各向异性对质子谱有明显的影响,特别是H8(H8′);而其对环碳的影响可以忽略。  相似文献   

3.
本文研究了含硼四元水盐体系MgB4O7-MgO4-MgCl2-H2O及次级体系MgB4O7-MgSO4-H2O和MgB4O7-MgCl2-H2O在298.15K时不同离子强度下的稀释热和热容,并将Debye-Huckel极限公式应用到多元电解质稀溶液中,获得从高离子强度到低离子强度I为19-0.0001范围内的相对表观摩尔焓.  相似文献   

4.
本文报道了以2-(6-甲基-2-苯并噻唑偶氮)-5-二乙氨基酚(MBTAE)作柱前衍生化试剂,在SpherisorbC_8柱上,以甲醇:水=80:20(V/V),含2mmol/LLi_2SO_4和10mmol/LpH5.0醋酸盐缓冲溶液作流动相,反相高效液相色谱分离和测定了Fe ̄(2+)、Co ̄(2+)、Ni ̄(2+)和Cu ̄(2+)。各金属离子的检出限(S/N=3)分别为(pg):Fe ̄(2+)6.40,Co ̄(2-)1.38,Ni ̄(2+)4.47,Cu ̄(2+)7.28。方法用于欧洲标准局,黑麦草标样的分析,所得结果与标准值相符。  相似文献   

5.
通过Fe3(CO)12、硫醇(硫酚)和EtMgBr所形成的络盐[(μ-CO)(μ-RS)Fe2(CO6)》-Mg^+Br与氯代芳酰氯的原位反应,合成了通式为(μ-RS)(μ-o-ClC6H4CO)Fe2(CO6)和(μ-RS)(μ-m-ClC6H4CO)Fe2(CO)6(R=n-Bu,t-Bu,Ph)的6个新桥芳酰基铁硫配合物,并用C/H分析、IR和^1HNMR表征了它们的结构。  相似文献   

6.
化学衍生—高效液相色谱法同时测定铅(Ⅱ)和汞(Ⅱ)   总被引:1,自引:0,他引:1  
从吡啶-2-乙醛苯甲酰腙作柱前衍生试剂,在优化了衍生和色谱条件下实现了用高效液相以谱法同时测定铅和汞离子,在phenomenexspherexC18色谱柱上,用甲醇-水(65:35,V/V),作流动相,于248nm处检测,得到线性良好的工作曲线,铅和汞的最低检测限分别为2.55μg/L和7.29μg/L。分析了环境水样品和合成水样,铅和汞的标准加入回收率分别为98.3%~101.7%和98.0~1  相似文献   

7.
D-HQADMB分光光度法测定微量镉(Ⅱ)   总被引:2,自引:0,他引:2  
研究了新显色剂4,4’-二[(8-羟基喹啉)偶氮]-3,3’-二甲基联苯(D-HQADMB)与Cd(Ⅱ)的显色反应条件。在吐温-80存在下的pH7.8~9.0的缓冲介质中,Cd(Ⅱ)与D-HQADMB形成稳定的红色配合物,组成比为Cd(Ⅱ)+D-HQADMB=1+2,λmax=530nm,表观摩尔吸光系数为7.20×104L/mol·cm,Cd量在0~1.3μg/mL范围内符合比耳定律。用制定的方法测定矿样中的微量镉,结果满意。  相似文献   

8.
SYNTHESISOF7-DEOXY-1,2,10,20-TETRAHYDROTAXAMAIRINB¥XueChaoFVANG,YuXinCUI,XinFuPAN,YaoZuCHEN(DepartmentofChemistry.NationalLab...  相似文献   

9.
通过Fe3(CO)(12)、硫醇(硫酚)和EtMgBr所形成的络盐[(μ-CO)(μ-RS)Fe2(CO)6]-Mg+Br与氯代芳酰氯的原位反应,合成了通式为(μ-RS)(μ-o-ClC6H4CO)Fe2(CO)6和(μ-RS)(μ-m-ClC6H4CO)Fe2(CO)6(R=n-Ru,t-Bu,Ph)的6个新桥芳酰基铁硫配合物,并用C/H分析、IR和1HNMR表征了它们的结构。  相似文献   

10.
SYNTHESIS OF 5-SUBSTITUTED-2-CHLORO-6-METHYL-4, 7-DIOXOBENZOTHIAZOLE DERIVATIVES¥CuiHuaLIU;BinLU;JingLingZHANG(Instituteoforg...  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.

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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.
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   

16.
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   

17.
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   

18.
The enthalpies of solution of several oxosulfides of rare-earth elements and the high-temperature enthalpies of oxosulfides and oxosulfates of lanthanum and yttrium were measured using solution calorimetry and high-temperature microcalorimetry techniques. Standard enthalpies of formation and some thermodynamic properties of oxosulfides and oxosulfates were calculated. Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 2 pp. 294–297, February, 1997.  相似文献   

19.
20.
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   

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