固相萃取-气相色谱-质谱法测定纺织品中全氟辛烷磺酸盐

采用固相萃取-气相色谱-质谱法测定纺织品中全氟辛烷磺酸盐的含量。纺织品样品在索氏提取器中用甲醇提取后,经固相萃取净化,并用盐酸溶液酸化,再与四丁基氢氧化铵反应。在气相色谱分离中用HP-5MS毛细管柱为固定相,在质谱分析中采用全扫描和选择离子监测模式。全氟辛烷磺酸盐的质量浓度在1.0~30.0mg·kg-1范围内与其峰面积呈线性关系,方法的检出限(3S/N)为0.13mg·kg-1。加标回收率在88.8%~91.1%之间,测定值的相对标准偏差在均小于5.0%。     

油/水界面张力的影响因素及无机盐对油水铺展的影响

讨论不同有机相与水形成的油/水界面处水/气、油/气及油/水3个界面张力的影响因素及相对大小。重点讨论了加入无机盐对作用于透镜状油滴上的3个界面张力的影响,总结出基本的规律并进行了实验验证。     

Interaction of Plasma Proteins with Tri‐quaternary Ammonium Salt Cationic Surfactant Studied by QCM‐D

A tri‐quaternary ammonium salt cationic surfactant was synthesized. Its structure was confirmed by using Fourier‐transform infrared spectroscopy, ¹H nuclear magnetic resonance spectroscopy, and X‐ray photoelectron spectroscopy analyses. Three model surfaces, including Au‐CH₃, Au‐OH and Au‐COOH, were fabricated. Adsorptions of surfactant on the three model surfaces and subsequent plasma proteins adsorption were investigated by quartz crystal microbalance with dissipation (QCM‐D). The mass of surfactant on the Au‐COOH surface was the largest, followed by that on the Au‐CH₃ surface, and that on the Au‐OH surface. These results suggested that the main driving force of surfactant immobilization was electrostatic interaction followed by hydrophobic interaction. Based on the results obtained, we concluded that the protein mass adsorbed on Au‐CH₃‐ S , Au‐OH‐ S , and Au‐COOH‐ S surfaces depended on the protein size and orientation. The mass and thickness of S on the Au‐COOH surface is the largest and the protein adsorption capacity of Au‐COOH‐ S surface is inferior to that of Au‐CH₃‐ S . The Au‐COOH‐ S surface could inhibit lysozyme adsorption, maintain the adsorption balance of bovine serum albumin, and induce fibrinogen‐binding protein adsorption.     

亲电二氟甲基试剂S⁃(二氟甲基)硫𬭩盐对1,1⁃偕二氰基烯烃的二氟甲基化: 二氟甲基取代全碳中心的有效构建

An efficient approach for difluoromethylation of dicyanoalkylidenes by electrophilic S-（difluoromethyl）sulfonium salt under organic base was described. A wide range of structurally and functionally diverse dicyanoalkylidenes was readily transferred into corresponding desirable difluoromethylated compounds bearing difluoromethylated all-carbon-substituted centers in good to excellent yields under standard reaction conditions.     

磷光软盐配合物及其光电应用研究

磷光软盐配合物是一种通过静电力和范德华力结合的带有相反电荷金属配合物的光电材料,它们的发射光谱通常由两个独立部分组成.与单组分磷光金属配合物相比,磷光软盐配合物含有更丰富的激发态,不同组分之间还存在能量传递过程.最近几年,磷光软盐配合物作为一类新兴的光电材料,在不同的光电领域表现出潜在的应用前景,并取得了一定的进展.本综述详细介绍了磷光软盐的合成与光物理性质,并对它们在有机发光二极管、生物成像、光动力治疗、电致发光变色等领域的应用进行了总结.     

Reaction of small molecules O2, NO,CO, and the Naldini salt (PPh3)2MnBr2: Characterized by infrared spectroscopy,elemental analysis,and single-crystal X-ray diffraction

Addition of 2 equiv. of PPh₃ to MnBr₂ in tetrahydrofuran (THF) solution under N₂ atmosphere results in the formation of Naldini salt (PPh₃)₂MnBr₂ ( 1 ). Reaction of Complex 1 and O₂, NO, and CO (with reducing agent) leads to Complex (OPPh₃)₂MnBr₂ ( 2 ), (PPh₃)₂Mn(NO)Br₂ ( 3 ), and (PPh₃)₂Mn(CO)₃Br ( 4 ), respectively. Both Complexes 2 and 4 crystallize in the triclinic space group P-1 with a = 9.94 Å, b = 10.11 Å, c = 10.53 Å; α = 65.42°, β = 63.16°, and γ = 89.22° of 2 and a = 10.23 Å, b = 12.26 Å, c = 14.44 Å and α = 97.03°, β = 104.34°, and γ = 106.33° of 4 . The isoelectronic replacement of 3CO with 2NO yields the {Mn(NO)₂}⁸ species (PPh₃)₂Mn(NO)₂Br ( 5 ). The single crystal of 5 is in the monoclinic space group C2/c with a = 23.17 Å, b = 9.62 Å, c = 15.92 Å, and β = 114.91°. In the THF solution, Complex 5 serves as an NO source in the presence of NO trapping, Co(TPP), Co(TPP) = 5,10,15,20-tetraphenyl-21H,23H-porphine cobalt(II).     

Dielectric relaxation and ion transport in silver–boro-tellurite glasses

Glass systems of composition xAg₂SO₄–20Ag₂O–(80?x) [0.50 B₂O₃–0.50 TeO₂], where x = 5, 10, 15, 20, 25 and 30 mol% have been prepared by melt-quenching technique. Frequency- and temperature-dependent conductivity measurements have been carried out in the frequency range 10 Hz to 10 MHz and at a temperature range of 303–353 K, respectively. DC conductivities exhibit Arrhenius behavior over the entire temperature range with a single activation barrier. Addition of Ag₂SO₄ expands the glass network and, consequently, conductivity increases. This suggests that the structure and network expansion are the key parameters for enhancing conductivity. Impedance spectra of these glasses show a single semicircle, indicating one type of conduction. AC conductivity behavior of the glasses was analyzed using both single power law and Kolhrauh–William–Watts (KWW) stretched exponential relaxation function. The power law exponent (s) is temperature-dependent, while the stretched exponent (β) is insensitive to temperature. Scaling behavior has also been carried out using reduced plots of conductivity with frequency, which suggests the ion transport mechanism remains unaffected by temperature and composition.     

Nachruf Prof. Hübner

Abstract

Representative water samples were collected from different oases in the western desert of Egypt to examine characteristics of Egyptian groundwater. Chemical data recognized two basic groundwater types; alkali bicarbonate and alkali chloride, where sodium has the highest concentration. For each region the median SD, δ¹⁸ 0 and ionic strength of water calculated from their chemical analyses are recorded and plotted.

Generally, the results of isotopic content measurements of the groundwaters from the different oases in the western desert indicate the fossile origin of these waters. The values of δD and δ¹⁸ 0 of the western desert oases' waters are characteristic of old paleowaters from the Nubian sand aquifer. Modern sparse rainfall data suggest that any precipitation will exhibit moderate to large positive isotopic content enrichments and cannot be a source for these waters. They have been in no connection with the Nile water, moreover the change in isotopic composition is due to evaporation which is now ineffective at deeper levels.     

Determination of δ2H and δ18O in saline oil-associated waters: the question of simple vacuum distillation of water samples prior to isotopic analyses

The paper deals with analytical and procedural aspects of δ¹⁸O and δ²H determination in saline oil-associated waters. The main objective of the study was to show experimentally the qualitative and quantitative applicability of the simple vacuum distillation of saline oil-associated waters while routine procedures of water isotopic analyses are applied. Additionally, two standard off-line techniques of δ²H determination in water – the zinc and the chromium method – have been compared. Each time a typical isotope salt effect has been tracked on the Dead Sea water. The results clearly show that application of the simple vacuum distillation improve the accuracy and reproducibility of δ²H determinations, especially in chromium off-line technique which appeared to be more sensitive to water salinity. The simple vacuum distillation does not improve the quality of δ¹⁸O determinations in the range of water salinities studied. Its application to high concentrated brines (for example, Dead Sea water) decreases the time of equilibration but still propagate the isotopic error connected with low water activity (in the case of ¹⁸O/¹⁶O ratio) and the incomplete water extraction from the remaining salts (in the case of ²H/¹H ratio); in consequence, its time-consuming application seems to be baseless.     

Energiespeicherung bei der Bestrahlung von Steinsalz

Zur Ermittlung der gespeicherten Energie bei der Einwirkung ionisierender Strahlung auf Steinsalz und den Bedingungen ihrer Freisetzung wurden lichtspektroskopische Absorptionsmessungen und differentialthermoanalytische Unter-suchungen an in einer ⁶⁰Co-Bestrahlungsanlage bestrahlten Steinsalzproben durchgeführt. Im untersuchten Bereich der Energiedosis von 1 ? 10⁶ Gy bis 5 ? 10⁷ Gy beträgt die gespeicherte Energie 0,12 bis 1,5 kJ/kg. Der Hauptteil der gespeicherten Energie wird bei Erwärmung zwischen 200 °C und 350 °C freigesetzt. Es wird eingeschätzt, daß durch die gespeicherte Energie im Steinsalz keine Gefährdung bei der Endlagerung radioaktiver Abfälle eintritt.