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1.
甲基磺酰氯的新合成方法甄小丽,康汝洪,韩建荣(河北轻化工学院基础部,石家庄050018)(河北师范大学化学系,石家庄050016)甲基磺酰氯是合成医药、农药的重要化工原料;也是酯化、聚合反应的催化剂;蒽醌,咔唑类染料的氯化剂;油墨、涂料的速固剂等,用...  相似文献   

2.
合成正丁基磺酰氯的新方法党占青康汝洪(石家庄师专化学系050041)(河北师范大学化学系石家庄050016)烷基磺酰氯是酯化、聚合的催化剂,油墨、涂料的固化剂,染料、医药、农药等的重要化工原料。其合成方法已有许多报道,文献 ̄[1-16]是以硫醇、二烷...  相似文献   

3.
四个香豆素磺酰氯衍生物的合成及其荧光性能的研究   总被引:2,自引:0,他引:2  
四个香豆素磺酰氯衍生物的合成及其荧光性能的研究曹秋娥,徐其亨(云南大学化学系,昆明,650091)关键词香豆素磺酰氯衍生物,荧光试剂,荧光性能香豆素衍生物是一类较好的荧光试剂,本文以香豆素为母体,合成了4个香豆素磺酰氯衍生物:4-甲基-7-羟基香豆素...  相似文献   

4.
本文概述了甲基磺酰氯的合成方法,作者对以硫脲为原料的合成工艺进行了深入的研究,改进后的合成工艺使产品产率提高了10%。  相似文献   

5.
索福喜 《大学化学》1994,9(3):35-36
关于甲基橙制备实验的两点意见索福喜(安阳师范专科学校化学系河南455000)甲基橙系由对氨基苯磺酸与亚硝酸钠和盐酸,经重氮化反应生成重氮盐,再与N,N-二甲基苯胺进行偶合制备。制备所及的重氮化及偶合反应,是合成偶氮染料的两个基本反应,有重要的工业价值...  相似文献   

6.
以对氨基苯磺酰胺、丙烯酰氯(或甲基丙烯酰氯)为原料合成了N-[4-(磺酰胺)苯基]丙烯酰胺(ASPAA)和N-[4-(磺酰胺)苯基]甲基丙烯酰胺(ASPMAA),其结构经^1H NMR,IR和元素分析表征。合成ASPAA的最佳条件:对氨基苯磺酰胺13.76g(80mmol),n(对氨基苯磺酰胺):n(丙烯酰氯)=1.0:1.1,n(丙烯酰氯):n(NaHCO3):1.00:1.14,0℃~2℃反应3h,反应液倾入10倍体积的的甲醇-水[V(甲醇):V(水)=1:10]中析出产物,收率在60%以上。合成ASPMAA的最佳条件:对氨基苯磺酰胺6.88g(40mmol),n(对氨基苯磺酰胺):n(甲基丙烯酰氯)=1.00:1.05,n(三己胺):n(甲基丙烯酰氯):1.0:1.0,在0℃~2℃滴加甲基丙烯酰氯后先在室温下反应1h,然后在60℃反应1h,反应液倾入700mL石油醚中析出产物,收率50%~60%.  相似文献   

7.
刘国正 《应用化学》1995,12(5):103-104
改进的亚磷酸二乙酯法合成亚甲基二膦酸四乙酯刘国正(北京师范大学化学系北京100875)关键词亚甲基二膦酸四烷基脂,亚磷酸二乙酯,合成MDP(MethyleneDiphosphonates)的四烷基酯是颇具实用价值的化合物,它与活泼金属反应可生成盐,可...  相似文献   

8.
3-甲基-4-(1-吡咯烷基)苯基重氮氯化锌复盐的合成唐有根蒋金芝*刘春健(中南工业大学化学系长沙410083)关键词重氮感光剂,甲基吡咯烷基苯基重氮氯化锌,合成1996-09-04收稿,1997-03-31修回光敏性重氮盐是非银感光材料中的一大类,...  相似文献   

9.
全甲基硅桥联双环戊二烯的合成   总被引:2,自引:0,他引:2  
全甲基硅桥联双环戊二烯的合成邝代治(衡阳师范专科学校化学系,421008)环戊二烯及其衍生物与过渡金属配合物的合成是金属有机化学中非常活跃的研究课题。人们在这些研究领域中感兴趣的是用各种基团来修饰环戊二烯配体,近来桥联双环戊二烯的合成已有不少报道 ̄[...  相似文献   

10.
二氯菊酸2—甲基—3—(2—呋喃基)—2—丙烯酯的合成   总被引:1,自引:0,他引:1  
涂君俐  肖蓉 《合成化学》1995,3(1):94-96
报导了一种新拟除虫菊酯的设计和合成,标题化合物是由二氯菊酰氯与新自制的2-甲基-3-(2-呋喃基)-2丙烯-1-醇酯化合成。  相似文献   

11.
丙烯酰胺双水相聚合体系稳定性研究   总被引:11,自引:0,他引:11  
通过浊点滴定法测定了不同温度下PAAmPEGH2O双水相体系相图,发现分相浓度随着温度的升高先增后降,55℃时分相浓度最低.双水相聚合体系微观结构显示,分散相以砾状液滴形式均匀分散在连续相中.研究了聚合过程中聚合体系粘度的变化,以及聚合温度、分散介质、单体、引发剂及乳化剂等对聚合体系最终粘度的影响,聚合体系最终粘度在一定范围内随分散介质和单体浓度增加变化不大,但是超过某一浓度后聚合体系粘度急剧增加;聚合体系中加入少量乳化剂对体系粘度影响不大,但加入大量乳化剂后体系稳定性变差,聚合体系粘度急剧增加;聚合体系最终粘度随着聚合温度升高先降后增,与相图的预测结果一致.  相似文献   

12.
Iron oxide (Fe2O3) was identified and characterized by surface area, X-ray diffractometry, and FTIR analyses. Surface charge densities, point of zero charge (PZC), and surface ionization constants were determined from the potentiometric titration data in various aqueous and aqueous organic mixed solvents in the temperature range 293-313 K. The surface charge densities were observed to decrease with the increase in temperature and concentration of metal ions in both the aqueous and aqueous organic mixed solvents. The absolute values of the surface charge density were found to change in the order aqueous > aqueous/methanol > aqueous/ethanol. Further, the PZC of the iron oxide was observed to shift to the higher pH values in the order ethanol > methanol > aqueous solution, which indicated a decrease in the acidity of the surface -OH groups. The pKa1 and pKa2 values of iron oxide were also determined and then used for determination of the surface potential (psi0) of the solid in aqueous and aqueous organic mixed solvents. The surface potential-surface charge curves generally supplemented the results derived from psi0-pH curves.  相似文献   

13.
Our NMR experiments show that chitin can dissolve well in aqueous KOH through a freeze-thawing process, and the dissolution power of the alkali solvent systems is in the order of KOH > NaOH > LiOH aqueous solution, which is totally contrary to that of cellulose in the alkali aqueous solution (i.e., LiOH > NaOH ? KOH). In this work, we systematically study the dissolution process in KOH and KOH/urea aqueous solutions. Chitin has good solubility (solubility ~80 %) in 8.4–25 wt% KOH aqueous solution at ?30 °C. The role of urea also has been investigated: unlike aqueous chitin-NaOH solutions, urea indeed enhances the solubility of chitin in KOH aqueous solutions, but the increased degree becomes unobtrusive with decreasing temperature and increasing dissolution time; the DA decline curves of chitin-KOH and chitin-KOH/urea aqueous solutions are nearly overlapping, indicating that the effect of the urea on the degree of acetylation of chitin in KOH aqueous solutions is small, similar to the NaOH/urea solvent.  相似文献   

14.
A theoretical model for analyzing the steric repulsion energy between internal aqueous droplets and the external aqueous phase in double emulsions, which results from the steric interaction between the surfactant molecules adsorbed at the two interfaces, has been established. The steric interaction is dependent on the separation distance between the internal aqueous droplets and the external aqueous phase, the thicknesses of the two adsorbed surfactant layers, and the size of the internal aqueous droplets and the oil globules, all of which determine the extent of the compression of the adsorbed surfactant molecules. The thickness of each of the two surfactant layers have the same effect on the steric repulsion, and stronger steric interaction can be achieved with thicker adsorbed layers, which can effectively prevent coalescence between the internal aqueous droplets and the external aqueous phase. Increasing the internal aqueous droplet size can produce stronger steric repulsion; however, larger oil globules will weaken the steric repulsion, indicating that a more stable double-emulsion system can be achieved by preparing the system with smaller oil globules and larger internal aqueous droplets.  相似文献   

15.
In this work, an aqueous extraction method has been combined with a preparative LC for isolation of 10-deacetylbaccatin III (10-DAB) from leaves of Taxus baccata L. The extracted aqueous solution showed two major peaks in LC. Semi-preparative-LC was used for isolation of these peaks. Nano liquid chromatography-Fourier transform mass spectrometry and nuclear magnetic resonance showed that these peaks belong to taxine B and 10-DAB in the extracted aqueous solution. The residual sample of aqueous extraction solution was extracted again by MAE. The amount of paclitaxel in Taxus baccata L. was compared with and without aqueous extraction and results showed that paclitaxel was stable and had no significant difference in concentrations during this aqueous extraction process.  相似文献   

16.
记录了常温下二钼酸铵晶体饱和水溶液的Raman光谱,并分别与二钼酸铵晶体、仲钼酸铵晶体、仲钼酸铵晶体饱和水溶液、水溶液状态下单钼酸根离子的Raman光谱进行了比较研究。结果表明:二钼酸铵晶体饱和水溶液Raman光谱相对二钼酸铵晶体Raman光谱,明显地发生了变异现象。二钼酸铵晶体饱和水溶液Raman光谱其主要特征峰最高振动频率937.6 cm-1与仲钼酸铵晶体饱和水溶液Raman光谱主要特征峰最高振动频率937.6 cm-1完全吻合,而其次高振动频率893.9 cm-1,恰好介于水溶液中单钼酸根离子Raman光谱主要特征峰最高振动频率895.1 cm-1与仲钼酸铵晶体饱和水溶液Raman光谱主要特征次高峰振动频率891.0 cm-1之间,而且三者彼此接近。二钼酸铵晶体饱和水溶液Raman光谱主、次特征峰强度之比值为2.1,与仲钼酸铵晶体饱和水溶液Raman光谱主、次特征峰强度之比值4.4相比,一半不足。提出了一种利用Raman光谱主要特征峰振动频率及其主、次特征峰强度之比值对二钼酸铵晶体饱和水溶液组分同时进行定性和半定量分析的新方法。发现了常温下二钼酸铵晶体饱和水溶液中二钼酸根离子Mo2O72-已经不复存在,完全转变成了优势组分仲钼酸根离子Mo7O246-和次要组分单钼酸根离子MoO42-;证明了常温下含钼水溶液酸化过程中溶液Raman光谱离散性变化现象的存在。运用结构化学和物理化学原理同时讨论了二钼酸铵晶体饱和水溶液Raman光谱发生变异现象的机理。  相似文献   

17.
A study of the extraction of chromium(VI) from aqueous media by ketones was made. Extraction of chromium was found to be most efficient from aqueous hydrochloric acid solutions. A mechanism for the extraction of chromium(VI) from aqueous hydrochloric acid solutions by methyl isobutyl ketone is proposed involving the formation of a receptor in the organic phase, the exchange of the chloride ion of the receptor for the anionic chromium(VI) species of the aqueous phase, and the solvation of the extracted chromium species. The differences in the abilities of various ketones to extract chromium(VI) from aqueous hydrochloric acid solutions, and the differences in the extraction of chromium (VI) from various aqueous acids by methyl isobutyl ketone are attributed to the differences in the formation of receptors.  相似文献   

18.
We compared the photochemical reaction of m-cresol containing OH precursors such as H2O2, NO2- and NO3- in aqueous solution with those in ice. The results show that the conversion rate of m-cresol in aqueous solution was higher than that in ice. H2O2, NO2- and NO3- all accelerated the photoconversion of m-cresol in both aqueous solution and ice. The photochemical reactions of m-cresol obeys the first order kinetics equation. According to the photoproducts identified by GC-MS, we proposed that hydroxylation and nitration reactions occurred in both aqueous solution and ice. Coupling reaction was common in ice, however, in aqueous solution it was found only in UV system. Our results suggest that the photochemical reactions of m-cresol were different in aqueous solution and in ice.  相似文献   

19.
Butyl acrylate conventional emulsion (macroemulsion) and miniemulsion polymerizations were carried out with an oil‐soluble initiator (azobisisobutyronitrile) in the presence or absence of an aqueous‐phase radical scavenger. For macroemulsion polymerization, in the presence of an aqueous‐phase radical scavenger, no particle nucleation occurred, whereas in the absence of an aqueous‐phase radical scavenger, particle nucleation proceeded as expected. For miniemulsion polymerization, the rate of polymerization was much higher in the absence of an aqueous‐phase radical scavenger than in its presence. Furthermore, in the absence of an aqueous‐phase radical scavenger, the miniemulsion polymerization rate increased with reduced droplet size, whereas in the presence of an aqueous‐phase radical scavenger, the trend was reversed. It is concluded that (1) for macroemulsion polymerization, the contribution from free radicals originating in the aqueous‐phase is predominant in the micellar nucleation of particles; (2) free radicals originating in the particle phase contribute to the rate of polymerization and the contribution increases with an increase in the particle size; and (3) for polymer particles with diameters of up to approximately 100 nm, polymerization is initiated from free radicals originating in the aqueous phase. © 2002 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 40: 3200–3211, 2002  相似文献   

20.
李蕾  孙鹏  段雪 《应用化学》2001,18(6):0-0
水滑石;水分散体系;层状结构;Mg-Al-CO3水分散液的稳定性及流变性  相似文献   

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