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11.
Taphonomy of subfossil bark was assessed in Hallstatt, Upper Austria. Samples from the Bronze Age were compared with recent corresponding material from the same site. Preservation of the prehistoric samples was caused by storage in a salt and clay mixture. FTIR spectroscopy was used to determine differences in material chemistry. Principal Component Analysis was applied to display the segregation of the data set according to the different factors and to display the strength of the effects. Results revealed that deacetylation processes dominated aging processes. Focusing on two band regions at around 1730 and 1230 cm−1 a clear separation was achieved. Additionally some samples were selected for further analyses to investigate the influence of the inorganic matrix. Thermal analyses demonstrated an ash content of more than 15%mass. X-ray diffractometry revealed the presence of salt (dominant), gypsum, pyrite, quartz, and calcite minerals. 相似文献
12.
The solid-liquid equilibrium diagrams of binary mixtures involving magnesium nitrate hexahydrate with cobalt nitrate hexahydrate, nickel nitrate hexahydrate (partly), manganese nitrate tetrahydrate, and iron(III) nitrate nonahydrate and of magnesium chloride hexahydrate with cobalt and nickel chlorides hexahydrates and manganese chloride tetrahydrate, and the of two manganese salts were determined. Those diagrams that showed a simple eutectic were fitted by the Ott equation and where the required BET parameters were available, the magnesium salt rich parts of the liquidus were modeled by means of this method. 相似文献
13.
六次甲基四碲富瓦烯二碘盐的合成、晶体结构及其某些固态物性 总被引:1,自引:1,他引:1
在两相混合溶液中电解合成了HMTTeF·I_2盐的单晶。晶体属P2_1/n空间群,独立区里有一个HMTTeF分子,离子化发生在分子中的一个碲原子孤电子对上。粉末压片常温电导率为4.1×10~(-5)Scm~(-1)。喇曼光谱测定与电导率及X射线分析结果相符。 相似文献
14.
Chitrakara Hegde Arun M. Isloor Mahesh Padaki Hoong-Kun Fun 《Arabian Journal of Chemistry》2013,6(3):319-326
The present work describes about the synthesis and characterization of Polysulfone blend nanoporous membrane with nonwoven support. This Nonwoven support provides mechanical strength to membrane while filtration process and minimizes membrane fouling. Hence it helps in better membrane performance in terms of salt rejection, improved flux, thermal stability and fairly increases in proton conductivity. In this work we have used K.C.270 nonwoven material consisting of fine polyester fibers and has a thickness of below 110 μm. 相似文献
15.
本文合成了新显色剂2-(5-溴-2-噻唑偶氮)-5-二乙氨基苯甲酸(简称5-Br-TAEB),利用光度法测定了试剂的三级质子化常数,研究了它与镍显色反应的最佳条件,同时对表面活性剂及无机盐的作用机理进行了初步探讨。实验结果表明,在NaCl和NaDS存在下,pH=5.0~8.0范围内,5-Br-TAEB与镍形成稳定的蓝色络合物,络合比为Ni~(2+):5-Br-TAEB=1:2,摩尔吸光系数ε_(642)=1.23×10~5 SL·mol~(-1)·cm~(-1)。镍浓度在0~10μg/25ml范围内服从比尔定律,方法用于铝合金中镍的测定,结果满意。 相似文献
16.
Summary Molecular surface areas accessible to a 4 ? diameter spherical probe were calculated from crystallographic data for five proteins:
α-chymotrypsinogen A, lysozyme, trypsinogen, ribonuclease A and ribonuclease S. The retention factors of various proteins
were measured on stationary phases having polyether- and phenylligates and with aqueous eluents containing (NH4)2SO4, Na2SO4 or NaCl at pH 7.0. The logarithmic retention factors were plotted against the salt molality and the hydrophobic interaction
parameters evaluated from the limiting slopes of the plots at high salt concentrations for the proteins in the chromatographic
systems investigated. The hydrophobic interaction parameters thus obtained were linear in both the molecular surface areas
of the proteins and the molal surface tension increments of the salts. The experimental results obtained with these relatively
simple proteins of known molecular structure, which were available in high purity, support earlier theoretical predictions
for the dependence of the hydrophobic interaction parameter on the surface area of the protein and the surface tension raising
effect of the salt. 相似文献
17.
Shuangxi Jing Ren Sheng Dr. Xinxin Liang Prof. Dong Gu Dr. Yuhao Peng Prof. Juanxiu Xiao Prof. Yijun Shen Prof. Di Hu Prof. Wei Xiao 《Angewandte Chemie (International ed. in English)》2023,62(6):e202216315
An overall carbon-neutral CO2 electroreduction requires enhanced conversion efficiency and intensified functionality of CO2-derived products to balance the carbon footprint from CO2 electroreduction against fixed CO2. A liquid Sn cathode is herein introduced into electrochemical reduction of CO2 in molten salts to fabricate core–shell Sn−C spheres (Sn@C). An in situ generated Li2SnO3/C directs a self-template formation of Sn@C. Benefitting from the accelerated reaction kinetics from the liquid Sn cathode and the core–shell structure of Sn@C, a CO2-fixation current efficiency higher than 84 % and a high reversible lithium-storage capacity of Sn@C are achieved. The versatility of this strategy is demonstrated by other low melting point metals, such as Zn and Bi. This process integrates energy-efficient CO2 conversion and template-free fabrication of value-added metal-carbon, achieving an overall carbon-neutral electrochemical reduction of CO2. 相似文献
18.
Beatrice Lansbergen Srija Tewari Ireneusz Tomczyk Maik Seemann Henning Louis Buchholz Mike Rippegarten Daniel Chamier Cieminski Dr. Fabio Juliá Prof. Dr. Tobias Ritter 《Angewandte Chemie (International ed. in English)》2023,62(52):e202313659
We report the first reductive vinylation of alkyl iodides. The reaction uses a vinyl thianthrenium salt, a palladium catalyst, and an alkyl zinc intermediate formed in situ to trap the LnPdII(vinyl) complex formed after oxidative addition before it undergoes undesired homocoupling to form butadiene. 相似文献
19.
定标粒子理论计算非水溶液的盐效应常数 总被引:1,自引:0,他引:1
本文应用定标粒子理论计算了非电解质溶质在盐(NaI、或KI)和环丁砜组成的非水电解质溶液中溶解度的盐效应常数。硬球作用项采用Masterton-Lee的方法。软球作用项采用胡英等的径向分布函数处理方法, 并考虑进了偶极-偶极、偶极-诱导偶极、电荷-偶极和电荷-诱导偶极等相互作用。分子的硬球直径σ和能量参数∈/k由经验方程计算。由理论值和实验结果比较得出: 当σ_2取0.563 nm、离子半径取电子密度标度时, 理论值与实验值符合得较好。 相似文献
20.
Jingjing Zhang Xueqing Luo Xiaoxin Zhang Ying Xu Hongbo Xu Jinlong Zuo Dongmei Liu Fuyi Cui Wei Wang 《中国化学快报》2021,32(4):1442-1446
The urgent need for fresh water resource is a public issue facing the world. Solar distillation for seawater desalination is a promising freshwater production m... 相似文献