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1.
黄维垣  陈俭龙 《化学学报》1988,46(7):669-673
以Ce^4^+-NaHSO3存在的体系中, 全氟烷基碘与烯烃于50-70℃发生加成反应, 得到相应的加成物, 在Fe^3^+-NaHSO3引发下, 或全氟烷基亚磺酸钠存在下也能引发同样的加成反应. 在全氟烷基亚碘酸钠存在下, 于30℃的反应中没有发现全氟烷基亚碘酸钠的全氟烷基与烯烃的加成物形成.  相似文献   

2.
王巍 《应用化学》1987,(6):92-92
本论文分两个部分,第一部分"全氟及多氟烷基卤化物的亚磺化脱卤反应"对连二亚硫酸钠与全氟烷基碘化物的作用进行考察,在碘化物S-碘-3-氧杂-八氟磺酸钠进行亚磺化脱碘反应并得到验证后,将反应用于其他带极性基因的全氟烷基碘化物上,随即采用相转移催化及共溶剂技术将反应推广到一般的全氟碘代烷上,证明连二亚硫酸钠对广谱的全氟烷基碘化物都是一个有效的便利的亚磺化脱碘试剂。在亚磺化脱碘研究的同时,还进行了亚磺化脱澳研究,得到了相应的全氟烷基亚磺酸及1,1-二卤亚磺酸盐。将全氟碘代烷与电化学体系中连续产生的二氧化硫阴离子基反应,得到了预期的全氟烷基亚磺酸盐,从而证实了二氧化硫阴离子墓确实是作为亚磺化反应主体的亲核试剂,电化学亚磺化脱碘反应将异相反应转化为均相反应,是一种很有前途的合成方法。仲全氟卤代烷与连二亚硫酸钠反应只能得到脱卤氢化产物,这和伯全氟碘代烷亚硫化的副产物一起,都说明了在这还原性体系中全氟烷自由墓形成全纸烷基阴离子的可能性。  相似文献   

3.
黄维垣  胡里清  葛文正 《化学学报》1988,46(11):1105-1108
全氟烷基亚磺酸钠盐或银盐的水溶液, 与硝酸、亚硝酸或二氧化氮反应, 生成N,N-双全氟烷基羟胺, 产率中等, 并伴有全氟羧酸, 全氟酰胺和亚硝基全氟烷等副产物.  相似文献   

4.
全氟烷基亚磺酸钠盐或银盐的水溶液,与硝酸、亚硝酸或二氧化氮反应,生成 N,N-双全氟烷基羟胺,产率中等,并伴有全氟羧酸,全氟酰胺和亚硝基全氟烷等副产物.  相似文献   

5.
全氟烷基亚磺酸盐可由相应的全氟烷基碘代烷或溴代烷用亚磺化脱卤反应高产率地合成。  相似文献   

6.
黄维垣  陈俭龙 《化学学报》1987,45(5):445-449
全氟烷基亚磺酸钠与溴水反应,得到全氟烷基磺酰溴(RfSO2Br),(但在乙腈,乙酸等有机溶剂中与溴反应,则生成溴代全氟烷.在碘化钾水溶液中,全氟烷基亚磺酸钠与碘反应,生成碘代全氟烷.α,α-二氯多币烷基亚磺酸钠在类似条件下与溴水反应,生成1-溴-1,1-二氯多氟烷,与碘在磺化钾水溶液中反应,生成1-碘-1,1-二氯多氟烷.1-溴-1,1-二氯多烷及1-碘-1,1-二氯多氟烷易对烯键加成,也可与连二亚硫酸钠在温和条件下发生亚磺化脱溴及脱碘反应.α,α-二氯二氟乙基亚磺酸钠在强酸中比较稳定,与强碱,氧化剂或还原剂发生反应,得到相应的产物.  相似文献   

7.
黄维垣  陈俭龙 《化学学报》1988,46(9):895-899
全氟烷基磺酰溴与杂原子取代烯烃, 如溴乙烯, 乙酸乙烯酯, 三甲基硅乙烯加成, 得相应的加成物, 与烯醇硅醚反应, 水解后得到α位溴代酮和全氟烷基亚磺酸. 全氟磺酰氯与1-三甲基硅氧基-1-叔丁基乙烯在紫外光照下反应, 生成α位全氟烷基化的酮. 全氟烷基磺酰溴溴化苯酚和甲氧基苯, 得到对位溴化产物. α,α-二氯三氟乙基亚磺酸钠与溴水在20-25℃反应, 得α,α-二氯三氟乙基磺酰溴, 其化学反应性与全氟烷基磺酰溴类似, 但稳定性较差.  相似文献   

8.
黄维垣  胡里清 《化学学报》1988,46(11):1148-1149
报导了全氟烷基亚磺酸银与碘之间在二氯甲烷中的低温反应(-30℃). 生成相应的全氟烷基磺酰碘. 并用^1^9F NMR证实其结构, 磺酰碘与各种稀烃反应则可产生二种系列的加成物RfSO2CH2CHIR和RfCH2CHIR.  相似文献   

9.
本文就三价有机横 盐, 包括二芳基、芳基全氟烷基、芳基烯基、芳基炔基和芳基烯丙基碘 盐以及碘叶立德在有机合成上有用的反应进行综述. 这些反应包括C-, O-,N-和S-芳基化, 全氟烷基、烯基、炔基、烯丙基和亚烷基转移反应等.  相似文献   

10.
本文就三价有机碘鎓盐,包括二芳基、芳基全氟烷基、芳基烯基、芳基炔基和芳基烯丙基碘鎓盐以及碘叶立德在有机合成上有用的反应进行综述。这些反应包括C-,O-,N-和S-基化,全氟烷基、烯基、炔基、烯丙基和亚烷基转移反应等。  相似文献   

11.
The developed strategy permits determination in three steps of sixty-seven elements using inductively coupled plasma mass spectrometry (ICP-MS). Sodium, Mg, Si, S, Cl, K, and Ca are determined in a first step; B, Al, P, Cr, Fe, Mn, Ni, Cu, Zn, As, Se, Ag, Cd, Sb, Ba, Hg, and Pb are determined in a second step; and Li, Be, Ti, V, Co, Ga, Ge, Br, Rb, Sr, Y, Zr, Nb, Mo, Sn, Te, I, Cs, La, Ce, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, Lu, Hf, Ta, W, Pt, Au, Tl, Bi, Th, and U are analyzed in a third step. The figures of merit obtained are adequate to carry out water quality monitoring and other hydrochemical studies, such those based in the application of hydrochemical fingerprinting to water management.  相似文献   

12.
INAA and ICPES are compared for their discriminative power in obsidian source characterisation. Geological samples from the Aegean and Carpathian sources were analysed for Na, Sc, Fe, Co, Rb, Sb, Cs, Ba, La, Ce, Sm, Eu, Tb, Yb, Lu, Hf, Ta, Th, U by INAA and for B, Na, Mg, Al, K, Ca, Sc, Ti, Mn, Fe, Zn, Y, Yr, Cs, Ba, La, Ce, Sm, Eu, Gd, Tb, Yb, Lu, Hf by two ICPES procedures. It is shown that all techniques work successfully, however, INAA is more efficient in the chemical discrimination of neighbouring sources.  相似文献   

13.
Résumé On décrit la détermination de traces dans le germanium, le silicium et le sélénium. En appliquant des techniques gamma spectrométriques, précédées ou non de séparations chimiques il est possible de doser les éléments suivants dans (1) germanium: As, Cu, Au, Ga, Zn, Hg, Cr, Sn, Sb, Co, In, Ni, Ir, Se, Sc, Ag, Ta, Hf et U; (2) silicium: P, Au, Sb, Ga, Fe, K, Cr, Mo, Sn, As, Co, In, Zn, Cu, W, Ta, Na, Eu, Sm, La, Sc et T1; (3) sélénium: Cl, Br, I, P, S, Te, Na, K, Cr, Fe, Co, Cu, Zn, Ga, Sc, Ag, Cd, La, W, Au et Tl. Les concentrations et ou limites de détections varient de quelques parties par million à 10−3 parties par milliard.  相似文献   

14.
A facile route is described for the synthesis of a series of macrocyclic tetraamides 1, 4, 9, 12 - tetraazacyclo - 2, 3, 6, 7, 10, 11, 14, 15-tetrabenzo-cetanan - 5, 8, 13, 16 - tetraone (TCTCT), 1, 4, 10, 13 - tetraazacyclo -2, 3, 6, 8, 11, 12, 15, 17-tetrabenzo-octadecan-5, 9, 14, 18-tetraone(TCTOT) and 1, 4, 10, 13-tetraaza-cyclo-2, 3, 11, 12-dibenzo-6, 8, 15, 17-dipyrdyl-octadecan-5, 9, 14, 18-tetraone (TCPOT) derived from 1, 2-diaminobenzene based on a stepwise approach using diacid dichloride (1, 2-diacid dichloride benzene, 1, 3- diacid dichloride benzene, 2, 6 - diacid dichloride pyridine) or mix dianhydrides for ring closure. This method is applicable for the preparation of a variety of receptors of various ring size, heteroatom substitution and pendant chains.  相似文献   

15.
对海水中多种常量/微量元素分别用Mg(OH)_2共沉淀和直接稀释ICP-MS法进行方法比较研究,分别确定了这些元素适宜的准确分析方法,为海水中常量/微量元素的ICP-MS测定提供了实用的检测手段。结果表明,Mg(OH)_2共沉淀法能够实现对V,Cr,Mn,Co,Cd及稀土元素(La,Ce,Pr,Nd,Sm,Eu,Gd,Tb,Dy,Ho,Er,Tm,Yb,Lu)等19种微量元素的分离富集和准确测定;10倍直接稀释法能够同时准确测定海水中B,Sr,Li,Rb,I,V,Cr,As,Cd,U,Mo,Cu,Mn 13种微量元素,但不适合Zn,Ni,Co和Pb,以及稀土元素等在海水中浓度过低元素的测定;两种方法对适宜测定的元素均操作简便快速,具有较高的准确度和精密度。这两种方法联用,就可用约50 mL的海水实现大洋和近海海水中Co,La,Ce,Pr,Nd,Sm,Eu,Gd,Tb,Dy,Ho,Er,Tm,Yb,Lu(这15个元素采用Mg(OH)_2共沉淀法)及B,Sr,Li,Rb,I,V,Cr,As,Cd,U,Mo,Cu,Mn(这13个元素采用10倍直接稀释法)等28种元素的准确测定。  相似文献   

16.
In order to evaluate alternative analytical methodologies to study the geographical origin of ciders, both multi-elemental analysis and Sr isotope abundance ratios in combination with multivariate statistical analysis were estimated in 67 samples from England, Switzerland, France and two Spanish regions (Asturias and the Basque Country). A methodology for the precise and accurate determination of the 87Sr/86Sr isotope abundance ratio in ciders by multicollector inductively coupled plasma mass spectrometry (MC-ICP-MS) was developed. Major elements (Na, K, Ca and Mg) were measured by ICP-AES and minor and trace elements (Li, Be, B, Al, Sc, Ti, V, Cr, Mn, Fe, Co, Ni, Cu, Zn, Ga, As, Se, Rb, Sr, Y, Mo, Cd, Sn, Sb, Cs, Ba, La, Ce, W, Tl, Pb, Bi, Th and U) were measured by ICP-MS using a collision cell instrument operated in multitune mode. An analysis of variance (ANOVA test) indicated that group means for B, Cr, Fe, Ni, Cu, Se, Cd, Cs, Ce, W, Pb, Bi and U did not show any significant differences at the 95% confidence level, so these elements were rejected for further statistical analysis. Another group of elements (Li, Be, Sc, Co, Ga, Y, Sn, Sb, La, Tl, Th) was removed from the data set because concentrations were close to the limits of detection for many samples. Therefore, the remaining elements (Na, Mg, Al, K, Ca, Ti, V, Mn, Zn, As, Rb, Sr, Mo, Ba) together with 87Sr/86Sr isotope abundance ratio were considered for principal component analysis (PCA) and linear discriminant analysis (LDA). Finally, LDA was able to classify correctly 100% of cider samples coming from different Spanish regions, France, England and Switzerland when considering Na, Mg, Al, K, Ca, Ti, V, Mn, Zn, As, Rb, Sr, Mo, Ba and 87Sr/86Sr isotope abundance ratio as original variables.  相似文献   

17.
Instrumental neutron activation analysis (INAA) was applied to thedetermination of the concentration levels of Na, Mg, Al, Cl, K, Sc, Ti, V,Cr, Mn, Fe, Co, Ni, Cu, Zn, As, Se, Br, Rb, Sr, Zr, Mo, Ag, Cd, Sb, I, Cs,Ba, La, Ce, Nd, Sm, Eu, Tb, Dy, Yb, Lu, Hf, Ta, Hg, Th and U in three radiopharmaceuticals.The irradiation of the samples was carried out in a 0.5 kW Bariloche RA-6Research Nuclear Reactor and the induced gamma-activity was measured by gamma-spectrometry.INAA proves to be an accurate and precise technique to obtain a quick informationon the concentration levels of several minor and trace components in radiopharmaceuticals.The quantification of heavy toxic elements is required for the registrationof radiopharmaceuticals.  相似文献   

18.
We established Multitracer, a new versatile radiotracer technique, for simultaneous tracing of a number of elements in various chemical, environmental, and biological systems. Metal foil targets (typically Au, Ag, Ge, Cu and Fe) are irradiated with C, N, or O ions accelerated up to 135 MeV/nucleon by RIKEN Ring Cyclotron. Radiochemical procedures have been developed to remove the target material leaving the nuclides as Multitracer solutions containing various radionuclides of Be, Na, Mg, K, Ca, Sc, V, Cr, Mn, Fe, Co, Ni, Cu, Zn, Ga, As, Se, Br, Rb, Sr, Y, Zr, Nb, Mo, Tc, Ru, Rh, Pd, Ag, Cd, In, Sn, Te, I, Ba, Ce, Pm, Eu, Gd, Tb, Tm, Yb, Lu, Hf, W, Re, Os, Ir, Pt, and Hg. Multitracers enable efficient tracing of a number of elements, and comparison of their behavior under strictly identical experimental conditions. Such features will be demonstrated by means of an example of application to a model experiment for the study of removal mechanism of various elements from the ocean.  相似文献   

19.
The elemental compositions of Apollo 11 and Apollo 12 lunar soil samples 10084,141 and 12070,83 and Apollo 12 rock fragment 12063,73 were determined by non-destructive radioanalytical methods. Main mineral fractions and glasses separated from these samples were analyzed as well. Instrumental neutron activation analysis (INAA) was used to determine Na, Mg, Al, Si, K, Ca, Sc, Ti, V, Cr, Mn, Fe, Co, Ni, Zr, Cs, Ba La, Ce, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Tm, Yb, Lu, Hf, Ta, W, Ir, Au, Th and U. A method of delayed neutron counting was used for the determination of uranium, and non-dispersive radioisotopic X-ray fluorescence analysis was applied to the determination of Ti, Fe, Sr, Y and Zr.  相似文献   

20.
A combination of instrumental neutron activation analysis (INAA) and prompt gamma-ray activation analysis (PGAA) was used to value assign 35 elements in SRM soil 2709a (San Joaquin Soil). INAA with counting of short-lived radioisotopes was used for determination of Al, Au, Ca, Dy, K, Mg, Mn, Na, Ti, and V. Elements determined by INAA with counting of intermediate and long-lived radioisotopes included As, Ba, Ce, Co, Cr, Cs, Eu, Fe, Hf, La, Lu, Nd, Rb, Sb, Sc, Sm, Sr, Ta, Tb, Yb, Zn, and Zr. Thermal neutron PGAA was used for the determination of H, B, Si, K, Ti, Mn, Fe, Cd and Gd. Expanded uncertainties were determined for all values reported.  相似文献   

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