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Solubility of Oxygen in Some 1-1, 2-1, 1-2, and 2-2 Electrolytes as a Function of Concentration at 25°C 总被引:1,自引:0,他引:1
The solubility of oxygen has been measured in a number of electrolytes [(LiCl, KCl, RbCl, CsCl, NaF, NaBr, NaI, NaNO3, KBr, KI, KNO3, CaCl2, SrCl2, BaCl2, Li2SO4, K2SO4, Mn(NO3)3)] as a function of concentration at 25°C. The solubilities, mol (kg-H2O)–1, have been fitted to a function of the molality m (standard deviation < 3mol-kg–1)
where A and B are adjustable parameters and the activity coefficient of oxygen )O2) = [O2]0/[O2]. The limiting salting coefficient, k
S = (ln / m)m=0 = A, was determined for all salts. The salting coefficients for the chlorides and sodium salts showed a near linear correlation with the crystal molar volume V
cryst = 2.52 r
3. The salting coefficients determined from the Scaled Particle Theory were in reasonable agreement with the measured values. The activity coefficients of oxygen in the solutions have been interpreted using the Pitzer equation
where
is a parameter that accounts for the interaction of O2 with cations (c) and anions (a) with molalities m
a and m
c, and
accounts for interactions for O2 with the cation and anion pair (c-a). The
and
coefficients determined for the most of the ions are in reasonable agreement with the tabulations of Clegg and Brimblecombe. The values of
for most of the ions are a linear function of the electrostriction molar volume (Velect = V0 – V
cryst). 相似文献
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Condensation of 2-methyl-1-pyrroline with chloroacetone or 3-chloro-2-butanone using LDA in THF afforded novel 2-(3-hydroxy-2-methyl-1-alkenyl)-1-pyrrolines via a peculiar reaction mechanism instead of the anticipated 2-(3-oxobutyl)-1-pyrrolines. The intermediacy of 2-(2,3-epoxy-2-methylalkyl)-1-pyrrolines in the latter transformation was demonstrated by immediate reductive epoxide ring opening utilizing lithium aluminium hydride in diethyl ether. Furthermore, 2-(3-oxobutyl)-1-pyrroline was prepared via an alternative approach through alkylation of 2-methyl-1-pyrroline with 3-chloro-2-(methoxymethyloxy)-1-propene using LDA in THF, followed by acid hydrolysis. Reduction of 2-(3-oxobutyl)-1-pyrroline by sodium borohydride in methanol afforded the corresponding 2-(3-hydroxybutyl)-1-pyrroline in good yield. 相似文献
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A simple two-step method for the selective preparation of anomerically pure 1α- and 1β-(indol-2-yl)deoxyribose derivatives was developed. The synthesis was based on the Sonogashira reaction of 1α- and 1β-ethynyldeoxyribose and 2-haloanilines followed by a Pd-complex catalyzed cyclization to the corresponding indolyldeoxyribosides. 相似文献
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以苯胺为原料,经重氮化反应和改进的Meerwein芳基化反应合成了1-苯基-2-丙酮(2)。优化的Meer-wein芳基化反应条件为:醋酸异丙烯酯为溶剂,氧化亚铜为催化剂,n(氟硼酸重氮盐)∶n(氧化亚铜)=10∶1,反应温度35℃~40℃,反应时间6 h。在优化反应条件下,2的收率达91%。 相似文献
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Ohne Zusammenfassung 相似文献
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《合成化学》2004,(Z1)
During our synthesis of N-benzoyl-N'-aryl selenourea derivatives, we isolated the title compound. One of them was selected optically for the diffraction study. The crystal belongs to the Monoclinic space group P21/n, Mr = 353.27, a = 11.073(1)? , b = 5.745(1) ?, c = 24.356(5) ?, β = 92.10 (1) , V = 1548.3 (4) ?3, Z = 4, Dx=1.515 Mg/m3,λ(Mo Kα)=0.71073 ?,θ = 1.67-25,μ o = 2.428 mm-1 , T = 296 (2) K. View of the molecule showing the labeling of the non-H atoms are described as: The se… 相似文献
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WAN Jun LI Chun-li LI Xue-mei ZHANG Shu-sheng 《高等学校化学研究》2006,22(4):465-467
The title compound was synthesized and characterized by IR, ^1H NMR, elemental analysis and single crystal X-ray diffraction analysis. Its biological activities were also tested. The results show that the title compound reveals inhibiting activities towards wheat gibberellin, apple ringspot, tomato early blight, peanut cercospora arachidicola and stem wilt of asparagus. 相似文献
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采用一价铜盐为催化剂、二甲基甲酰胺为溶剂,在均相体系中催化3-氯-1-丁烯异构化生成1-氯-2-丁烯.考察了溶剂、反应温度、催化剂种类和加入量对反应的影响,研究发现反应温度和催化剂的加入量对异构化反应有较大影响.在最优条件3-氯-1-丁烯1 mL,二甲基甲酰胺9 mL,CuCl 0.10 g,60℃反应5 h,产物和原料的浓度比为3.88 mmol L-1.采用在线红外光谱对反应过程进行监测,检测到有红外吸收峰在反应过程中先增加后减少的变化过程,提出了可能的反应机理. 相似文献
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2-甲基-2-(2-硝基乙烯基)-1-苯并环酮的对映选择合成 总被引:3,自引:2,他引:1
在有些具有强烈生理活性的天然产物分子中,存在保持其特殊分子骨架的不对称季碳,是具有特定生理活性的决定性因素.利用SMP[S-(-)-2-methoxymethyl-pyrrolidine]作为手性离去基团,通过对映选择加成-消除反应构筑不对称季碳,是... 相似文献