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3硝基1,2,4三唑5酮(NTO)的锂盐水溶液与Yb2O3的稀硝酸溶液反应,制备了标题配合物,其化学式为Yb(NTO)3·10H2O。用X射线衍射法测定配合物的晶体结构,其分子式为[Yb(NTO)3(H2O)4]·6H2O。属单斜晶系,空间群为C2/c。晶胞参数如下:a=36931(5)nm,b=06683(10)nm,c=25656(3)nm,β=130974(5)°,V=47811(11)nm3,Z=8,Dc=2013g·cm-3,μ=4017mm-1,F(000)=2850。镱离子的配位数为7,其配位多面体为五角双锥。 相似文献
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合成了共15个未见文献报道的三价镧系离子与手性氮杂冠醚(+)-12-乙基-1,4,7,10-四氧杂-13-氮杂环十五烷(以下以L(+)表示)的配合物Ln(NO3)3·L(+)·H2O(Ln=La、Ce、Pr、Nd);Ln(SCN)3·L(+)·H2O(Ln=La、Pr、Nd、Sm、Eu、Gd-Er、Yb)。对所合成配合物进行了元素分析、电导、红外、可见吸收光谱、比旋光度和圆二色谱(CD谱)的测试,并对配合物的有关物理化学性质进行了讨论。 相似文献
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用Cadion-CPB光度法测定水中痕量阴离子表面活性剂 总被引:7,自引:0,他引:7
研究了用于直接测定水相中痕量阴离子表面活性剂的新体系。在NaOH介质中,1-(4-硝基苯基)-3-[4-(苯基偶氮)苯基]-三氮烯(Cadion)与溴化十六烷基吡啶(CPB)形成离子缔合物(Cadion-CPB),当加入阴离子表面活性剂(AS)时,AS能定量置换出离子缔合物中的Cadion,而使吸光度下降。阴离子表面活性剂十二烷基苯磺酸钠(DBOSO3Na)、十二烷基磺酸钠(DOSO3Na)、十二烷基硫酸钠(DSO4Na)的表观摩尔吸光系数εmax分别为2.74×104、1.11×104、1.50×104L·mol-1·cm-1,服从比尔定律的范围分别为0~4.18、0~6.54、0~5.77mg·L-1。方法操作简便,用于测定合成水样及环境水样中痕量阴离子表面活性剂,结果满意。 相似文献
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3,5—Br2—PADAP—IO^—30SCN—三元离子缔合物测定微量IO^— … 总被引:6,自引:0,他引:6
研究了3,5-Br2-PADAP在酸性介质中质子化,与IO^-3和SCN^-形成三元离子缔合物的最佳条件,其表现摩尔吸光系数为1.4*10^5L.mol^-1.cm^-1,缔合物组成比为3,5-Br2-PADAP:IO^3:SCN^-=1:1:1。 相似文献
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应用INDO/S半经验量子化学方法,对簇合物离子Mo3S和Mo3S4Mn+(M=Fe、Ni,n=4;M=Cu,n=5)分别进行分子轨道计算。根据计算得到的簇离子中的原子表观电荷和成键指标,说明Fe、Ni、Cu+与Mo3S成键作用的相对强度依次是Fe-Mo>Ni-Mo>Cu+-Mo。比较了用含组态作用的INDO/S方法计算得到的电子跃迁能与实验得到的电子吸收光谱值,并讨论了吸收峰归属情况。对于M为Fe、Ni的簇离子Mo3S4M4+,最低能量的电子跃迁吸收峰起源于异金属间电荷转移跃迁(MM’CT);而Mo3S4Cu(5+)簇离子观察到的吸收峰主要是Mo3S芯的局域内电荷转移跃迁。根据理论计算结果,由Cu+离子到Mo3S的电荷转移跃迁谱线,大约在46000cm-1以上才能观察到吸收峰。从Mo3S4Fe4+次低能量吸收峰的实验值16600cm-1和理论值16500cm-1与Mo3S的最低能量吸收峰的实验值16600cm-1和理论值16900cm-1比较,表明无论从理论上或实验上都能证实簇离子Mo3S4Fe4+在能量为16600cm-1处的吸收峰是起因于Mo3S芯的局域内电荷转移跃迁。 相似文献
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测定了Ln(ClO_4)_3-DAPTU-H_2O(Ln=La,Sm,Yb)三元体系在30℃时的溶解度及饱和溶液的折光率,绘制了相应的溶度图和折光率-组成图,各体系的溶度曲线和折光率曲线均由三支组成,分别与DAPTU、Ln(DAPTU)_2(ClO_4)_3·8H_2O(Ln=La,Sm,Yb)和Ln(ClO_4)_3·nH_2O(Ln=La,n=8;Sm,n=9;Yb,n=8)相对应。从溶度图上发现了3个未见文献报道的固液异组成溶解的化合物,通过化学分析及元素分析、TG-DTG、IR对其进行了表征。 相似文献
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反相离子对色谱法测定硫代硫酸根和碘离子的研究 总被引:4,自引:0,他引:4
首次利用S2O2-3和I-与Hg-EDTA二元络合物通过柱前衍生形成EDTA-Hg-S2O3和EDTA-Hg-I两种三元络合物的方法,实现了对S2O2-3和I-的间接反相离子对色谱分离和紫外检测。在ZorbaxODS柱上,用甲醇∶水=23∶77作流动相,内含对离子TBA+3.0mmol/L,EDTA1.0mmol/L,NaNO32.0mmol/L和缓冲剂KH2PO4-Na2HPO4(pH7.0),紫外254nm检测。S2O2-3和I-的最小检出限分别为61.1ng和37.6ng。方法简便,选择性好。 相似文献
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Ln(ClO4)3—DAPTU—H2O三元体系30℃时的相平衡研究 总被引:3,自引:4,他引:3
测定了Ln(ClO4)3-DAPTU-H2O(Ln=Ln,Sm,Yb)三元体系在30℃时的溶解度及饱和溶液的折光率,绘制了相应的溶度图和折光率-组成图。各体系的溶度曲线和折光率曲线均由三支组成,分别与DAPTU、Ln(DAPTU)2(ClO4)3·8H2O(Ln=La,Sm,Yb)和Ln(ClO4)3·nH2O(Ln=La,n=8;Sm,n=9;Yb,n=8)相对应。从溶度图上发现了3个未见文献报 相似文献
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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
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Cotton cellulose was swollen in a sodium hydroxide solution and carboxymethylated by a two-bath method for different periods of time for each process. The kinetics of acid hydrolysis and the crystallinity of the swollen and carboxymethylated samples were measured. The proportion of broken bonds, rate constants for hydrolysis, and permeability of cellulose to hydrolyzing agents were calculated. The susceptibility of glycosidic linkages to acid hydrolysis was improved by carboxymethylation more than by swelling in alkali. The increased accessibility of carboxymethylcellulose to acid was regarded as a consequence of increased intra-and intercrystalline swelling and of the glycosidic bonds' weakness caused by the electron-attracting carboxymethyl group on the C-6 position. 相似文献
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The aim of the presented work was the investigation of thermal oxidation of ilmenite in static air atmosphere. The investigations
were carried out by use of a derivatograph (MOM, Hungary). The changes of crystallographic structure of investigated samples
were identified by X-ray diffractometry on Philips PW-1710 diffractometer. In temperature above 500°C appears structure of
hematite Fe2O3. On the basis of the thermogravimetric measurements, the contracting area and contracting volume models were found as the
best fitting experimental data.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
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Cyclopropyl derivative of 2,6-di-tert-butylphenol is synthesized as a probe to investigate the mechanism of base-catalyzed autooxidation of phenol derivatives. Our study indicates that one electron reduction of molecular oxygen from phenolate gives phenoxyl radical 3, a key intermediate of autooxidation. The coupling of phenoxyl radical and superoxide radical gives peroxylate anion 4 and produces the final epoxy alcohol adduct 6. 相似文献
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微量钙的测定方法研究进展 总被引:5,自引:0,他引:5
介绍了1995-2006年期间测定微量和痕量钙的方法,如电感耦合等离子体-原子发射光谱法、原子吸收光谱法以及离子色谱法等的工作原理和特点,并说明了其测定微量钙的应用领域。并对微量钙的测定技术进行了展望(引用文献55篇)。 相似文献
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Thermal behaviour of sodium oxo-salts of sulphur: Na2SO4, Na2S2O7, Na2S2O6, Na2SO3, Na2S2O5, Na2S2O4, Na2S2O3, Na2S3O6 and of sulphides Na2S and Na2S2 was studied on heating up to 1000°C. The experiments were performed with anhydrous compounds obtained from commercial products
by recrystallisation and dehydration. The stage mechanisms of decomposition of anionic sub-lattices of the salts have been
proposed basing on the Górski’s morphological classification of simple species. The thermal stability and the stage decomposition
mechanisms were correlated with the structure and the potential chemical properties of the salt anions. The thermal decomposition
processes were studied by means of thermal analysis, and the decomposition products were identified by means of X-ray phase
analysis. 相似文献