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11.
Different Complexation Behavior of P‐Functionalized Ferrocene Derivatives Towards SnCl2, SnCl4 and SnPh2Cl2: Auto‐ionization and Redox‐Type Reactions 下载免费PDF全文
Dipl.‐Chem. Matthias Gawron Dr. Christina Dietz Michael Lutter Dr. Andrew Duthie Prof. Dr. Viatcheslav Jouikov Prof. Dr. Klaus Jurkschat 《Chemistry (Weinheim an der Bergstrasse, Germany)》2015,21(46):16609-16622
The novel phosphonyl‐substituted ferrocene derivatives [Fe(η5‐Cp)(η5‐C5H3{P(O)(O‐iPr)2}2‐1,2)] ( Fc1,2 ) and [Fe{η5‐C5H4P(O)(O‐iPr)2}2] ( Fc1,1′ ) react with SnCl2, SnCl4, and SnPh2Cl2, giving the corresponding complexes [(Fc1,2)2SnCl][SnCl3] ( 1 ), [{(Fc1,1′)SnCl2}n] ( 2 ), [(Fc1,1′)SnCl4] ( 3 ), [{(Fc1,1′)SnPh2Cl2}n] ( 4 ), and [(Fc1,2)SnCl4] ( 5 ), respectively. The compounds are characterized by elemental analyses, 1H, 13C, 31P, 119Sn NMR and IR spectroscopy, 31P and 119Sn CP‐MAS NMR spectroscopy, cyclovoltammetry, electrospray ionization mass spectrometry, and single‐crystal as well as powder X‐ray diffraction analyses. The experimental work is accompanied by DFT calculations, which help to shed light on the origin for the different reaction behavior of Fc1,1′ and Fc1,2 towards tin(II) chloride. 相似文献
12.
过氧化钠熔融分解样品,热水浸提,试样经铍盐做共沉淀剂,用乙二胺四乙酸(EDTA)消除钙、镁等的影响,在盐酸-氯化铵底液中,用极谱法对锡进行测定,改进并简化了国标方法.对极谱法测定地质样品中锡从熔矿方式、测试温度以及干扰元素的影响及消除等方面进行探讨,并对仪器的工作条件进行优化.锡的方法检出限为10.0μg/g.方法经标准物质验证,测定值与标准值相吻合,并进行不同仪器和方法的对比实验,结果一致,准确度高.方法精密度(RSD,n=12)低于2%.方法效率高、测定结果准确可靠,已应用于大量地质样品的分析中. 相似文献
13.
A Bis‐Sulfonyl O,C,O Aryl Pincer Ligand and its Tin(II) Complex: Synthesis,Structural Studies,and DFT Calculations 下载免费PDF全文
Mohammad El Ezzi Romaric Lenk Dr. David Madec Dr. Jean‐Marc Sotiropoulos Sonia Mallet‐Ladeira Dr. Annie Castel 《Angewandte Chemie (International ed. in English)》2015,54(3):805-808
The efficiency of the deprotonated aryl bis‐sulfone [2,6‐{(p‐tolyl)SO2}2C6H3]? as an O,C,O‐coordinating pincer‐type ligand was described. The bis‐sulfone precursor was synthesized using a straightforward palladium‐catalyzed cross‐coupling reaction. As a result of directed ortho metalation (DoM) through sulfonyl groups, a selective lithiation of the aryl group was achieved and the corresponding carbanion was isolated and its structure determined by single‐crystal X‐ray diffraction analysis. A heteroleptic tin(II) complex has been prepared by a nucleophilic substitution reaction. Crystallographic analysis and DFT calculations indicate that the bis‐sulfonyl moiety acts as a new O,C,O‐coordinating pincer‐type ligand with intramolecular S?O coordination to a tin(II) center. The cis form with the two nonbonded oxygen atoms of the sulfonyl groups on the same side is preferentially obtained. 相似文献
14.
王皓莹 《中国无机分析化学》2015,5(2):59-61
锡阳极泥是锡冶炼过程中的一种中间产物,其中含有大量的金、银等贵金属。准确测定锡阳极泥中金、银含量有很重要的现实意义。采用火试金法能实现锡阳极泥中金、银含量的连续测定,方法准确度高,精密度好,金、银回收率在97.46%~101.66%,能很好地满足锡阳极泥中高品位金、银的测定。 相似文献
15.
Preparation and Electrochemical Properties of Tin–Iron–Carbon Nanocomposite as the Anode of Lithium‐Ion Batteries 下载免费PDF全文
Dr. Xu Yang Dr. Rongyu Zhang Dr. Xiaofei Bie Prof. Chunzhong Wang Malin Li Dr. Nan Chen Prof. Yingjin Wei Prof. Gang Chen Dr. Fei Du 《化学:亚洲杂志》2015,10(11):2460-2466
Tin–iron–carbon nanocomposite is successfully prepared by a sol–gel method followed by a chemical vapor deposition (CVD) process with acetylene gas as the carbon source. The structural properties, morphology, and electrochemical performances of the nanocomposite are comprehensively studied in comparison with those properties of tin–carbon and iron–carbon nanocomposites. Sheet‐like carbon architecture and different carbon contents are induced thanks to the catalytic effect of iron during CVD. Among three nanocomposites, tin–iron–carbon demonstrates the highest reversible capacity of 800 mA h g?1 with 96.9 % capacity retention after 50 cycles. It also exhibits the best rate capability with a discharge capacity of 420 mA h g?1 at a current density of 1000 mA g?1. This enhanced performance is strongly related to the carbon morphology and content, which can not only accommodate the large volume change, but also improve the electronic conductivity of the nanocomposite. Hence, the tin–iron–carbon nanocomposite is expected to be a promising anode for lithium‐ion batteries. 相似文献
16.
17.
3,5-二氟苄基氯和邻氯基苄基氯在适当的溶剂中与锡粉反应,合成了三(3,5-二氟苄基)氯化锡(1)和四(邻氯苄基)锡(2),经X射线衍射方法测定了新化合物的晶体结构。化合物1属单斜晶系,空间群为C2/c,晶体学参数:a=1.858 33(11)nm,b=1.140 98(7)nm,c=2.690 06(16)nm,β=109.288(10)°,V=5.383 6(6)nm3,Z=8,Dc=1.532 g·cm~(-3),μ(Mo Kα)=13.61 cm~(-1),F(000)=2 480,R1=0.085 1,wR~2=0.168 1。化合物2属单斜晶系,空间群为P21/m,晶体学参数:a=0.585 54(5)nm,b=1.969 74(18)nm,c=0.857 86(8)nm,β=95.204 0(10)°,V=0.985 34(15)nm3,Z=2,Dc=1.805 g·cm~(-3),μ(Mo Kα)=14.91 cm-1,F(000)=524,R1=0.054 0,wR_2=0.163 9;中心锡原子为畸变四面体构型。对其结构进行量子化学从头计算,探讨了化合物的稳定性、分子轨道能量以及部分前沿分子轨道的组成特征。测定了化合物的热稳定性。 相似文献
18.
A simple efficient strategy for the simultaneous synthesis and anchoring of liquid crystal (LC)-stabilised gold nanoparticles (NPs) on indium tin oxide (ITO) substrate is described. A monolayer of 3-mercaptopropyltrimethoxy silane (MPS) compound was formed on ITO and quality of the monolayer was assessed using electrochemical techniques namely cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS). Gold NP preparation was carried out on this monolayer-modified substrate (and on bare ITO), in a single-step reaction, simply by drop-casting a solution containing an appropriate amount of chloroauric acid and a LC compound possessing a terminal amino group, on the MPS monolayer-modified substrate and heating (70degree) for 2-3 min.. The LC compound served as a reducing agent as well as a capping ligand. LC-capped NPs were chemically anchored onto the ITO substrate through bonding to thiol moiety of the MPS. The CV and EIS analysis of the MPS monolayer showed a complete blocking behaviour for the electron transfer across the electrode/electrolyte interface confirming the formation of a high-quality dense compact monolayer. On the other hand, upon immobilisation of LC-gold NP composite on self-assembled monolayer-modified ITO substrates, both CV and impedance studies showed a small current indicating the gold NP-mediated electron transfer, thus confirming the successful immobilisation of NPs. 相似文献
19.
Electrical,optical, and structural characterization of p‐type N‐doped SnO thin films prepared by thermal oxidation of sputtered SnNx thin films 下载免费PDF全文
A. Garzon‐Fontecha W. De La Cruz M. Quevedo 《Surface and interface analysis : SIA》2017,49(12):1225-1231
We present a study of electrical and optical properties of nitrogen‐doped tin oxide thin films deposited on glass by the DC Magnetron Sputtering method. The deposition conditions to obtain p‐type thin films were a relative partial pressure between 7% and 11% (N2 and/or O2), a total working pressure of 1.8 mTorr and a plasma power of 30 W. The deposited thin films were oxidized after annealing at 250°C for 30 minutes. X‐ray diffraction results showed that the as‐deposited thin films exhibit a Sn tetragonal structure, and after annealing, they showed SnO tetragonal structure. X‐ray photoelectron spectroscopy results showed the presence of nitrogen in the samples before and after annealing. The measured physical parameters of the thin films were optical band gap between 1.92 and 2.68 eV, resistivity between 0.52 and 5.46 Ωcm, a concentration of p‐type carriers between 1018 and 1019 cm?3, and a Hall mobility between 0.1 and 1.94 cm2V?1s?1. These thin films were used to fabricate p‐type thin film transistors. 相似文献
20.
建立了火焰原子吸收光谱法(FAAS)测定锡阳极泥中银含量的方法。文章考察了不同的测定介质、酸度对测定结果的影响。实验结果表明在选定条件下,锡阳极泥中的锡、锑、铅等杂质不干扰银的测定。方法加标回收率在99.2%~103%,精密度实验结果表明,相对标准偏差(RSD,n=11)均小于4%。操作过程简单,能满足生产的需要。 相似文献