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1.
研究了含NaClO4的PEO400与环氧树脂所形成的完全无定形的互穿聚合物网络(IPN)固体电解质的电导率与压力和温度的关系.在室温至70℃和压力0—40MPa的范围内,这类IPN的电导率在6MPa左右出现极大值,超过6MPa以后,电导率随压力的增加而减小.计算了在不同压力下的激活体积.与含LiClO4的同类IPN体系进行了比较.从离子偶极作用原理出发对结果进行了讨论.实验表明离子通道畸变受运动离子的大小影响.离子半径越小,对离子通道影响越大,因而电导率改变也大.  相似文献   

2.
研究了碳酸丙烯酯(添加量5%)与γ-丁内酯(添加量10%)对由数均分子量为800的聚氧化乙烯(PEO800)大单体交联不饱和聚酯(含LiClO4)形成的接枝聚酯网络的离子导电性能影响,发现其电导率主要取决于体系中的LiClO4浓度.当[EO链节]/[Li+]=30时,室温电导率达最大值,σ298K=(4.0—4.5)×10-5Scm-1.这类接枝聚酯网络的玻璃化转变温度(Tg)同样取决于盐类浓度,而与网络的交联程度无关.网络中的极性添加剂并不显著影响其交联程度与Tg,但较大幅度提高离子导电性能,这可能与极性添加剂加速载荷离子在导电通道中的迁移性有关.若在上述接枝网络中引入环氧树脂网络,形成接枝聚合物互穿网络,则成膜后的机械强度有进一步提高,同时具有优良的室温电导率,σ298K=2.4×10-5Scm-1。  相似文献   

3.
聚环氧乙烷环氧丙烷—盐复合物的结构和导电性   总被引:3,自引:2,他引:3  
齐力  宋永贤 《应用化学》1993,10(5):61-65
制备了室温电导率较高(10^-4S·cm^-1),力学性能较好的环氧乙烷和环氧丙烷共聚物-Li-ClO4复合物薄膜,研究了共聚物组成对结晶及对复合物室温电导率的影响,考察了高氯酸锂浓度对复合物室温电导率的影响以及复合物电导的温度依赖关系,发现复合物中没有结晶配合物,其结晶度随聚合物结构和盐含不同而变化,室温下呈弹性体。  相似文献   

4.
本文报道了一个灵敏度高,选择性好的测定痕量钍的新光度分析法。在聚乙烯醇存在下,钍钼杂多酸和丁基罗丹明B形成离子缔合物,其适宜条件为CHClO4=1.3MOL/L,CMoO^2-4=6.8×10^-4mol/L,CBRB=2.7×10^-5mol/L,PVA0.08%。  相似文献   

5.
Cl-对API P105钢在含CO2溶液中的电化学腐蚀行为的影响   总被引:12,自引:0,他引:12  
用电化学阻抗谱(EIS)及极化测量,研究了在含CO2的溶液中Cl^-1对APIP105钢的电化学腐蚀行为的影响。结果表明,Cl^-促进了钢铁的阳极溶解,其电化学反应级数为0.7.Cl^-不参与钢铁的阴极反应,在含Cl^-的饱和CO2溶液中,阴极反应主要为H2CO3的去极化反应。  相似文献   

6.
低压离子色谱是作者提出的一种新的分析法,可以在1.96~2.94×10^5Pa低压分析碱金属,碱土金属,过渡金属阳离子,无机阴离子及许多有机酸离子,本文用低压离子色谱法分析了成都地区酸雨中Na,NH4,K^+,Mg^2+,Ca^2+,F^-,Cl^-,NO3^-,SO^2-4等离子,获得了满意的结果。  相似文献   

7.
聚醋酸乙烯酯与铜(Ⅱ)离子的配位反应及其催化作用   总被引:1,自引:1,他引:1  
以ESR、UV和IR表征Cu(2+)离子与PVAC的配位反应。根据CUCl2·2H2O乙醇溶液与PVAc-CuCl2·2H2O乙醇溶液的电导率差值随Cu(2+)离子摩尔浓度变化的明显转析点得知,1个Cu(2+)离子大约能与PVAc4个链节单元配位。证实MMA在Cu(Ⅱ)-PVAc配合物/Na2SO3体系的聚合体是无规PMMA,得率为70%。讨论了MMA在Cu(Ⅱ)-PVAc配合物/Na2SO3体系络合催化引发下的游离基反应历程。  相似文献   

8.
STEREOSTRUCTUREOFPOLY[4-(2-METHYLPROPENOYLOXY)-4'-CYANOBIPHENYL]BYPHOTOPOLYMERIZATIONUNDERANEXTERNALELECTRICFIELD¥ChongWuLI;A...  相似文献   

9.
姚德  刘辉 《分析试验室》1994,13(6):68-71
在0.2mol·L^-1NH4Cl-NH3·H2O底液中,(pH为9.26),得到一个极为灵敏的Fe(Ⅲ)-TEA-5-Br-PADAP-H2O2配合吸附催化波,其峰电位为-0.71V(vs.SCE)。铁浓度在1.8×10^-10 ̄5.4×10^-6mol·L^-1范围内与二阶导数波高呈线性关系。对该极谱波的性质进行了研究,证明是一种配合吸附催化波,并成功地应用于各类水样,钒催化剂中微量或痕量铁的  相似文献   

10.
研究了交替马酸酐共聚物多缩乙二醇酯(CP350)-LiNO3络合物的热行为及离子导电性。实验表明:CP350/LiNO3络合物在所研究的[Li]/[EO]配比范围呈均相无定形并具有二重玻璃化转变。2个玻璃化转变温度均随盐含量的增加而上升。离子电导率随盐浓度的变化出现1个极大值,室温电导率最大可达3.72×10^-5S/cm。导电行为呈典型VTF特征。  相似文献   

11.
用溶胶-凝胶法以磷钼酸(MPA)的镍盐溶液水解钛酸四丁酯制备了NiPMo/TiO2催化剂.使用ICP、 XRD、 TG-DTA、 IR、 TPD-MS和微反应技术研究了催化剂的化学组成、热稳定性、化学吸附性质和催化反应性能.杂多钼酸盐与TiO2通过O2-在TiO2表面发生了键合.在623 K下,杂多阴离子仍保持原有的Keggin结构.CO2在Lewis酸位Ni(Ⅱ)和Lewis碱位Ni-O-Mo的桥氧协同作用下生成CO2卧式吸附态Ni(Ⅱ)←O-(CO)←(O--Ni).丙烯有多种吸附态在催化剂上吸附.在563 K、 1 MPa和空速1500 h-1的反应条件下,丙烯的摩尔转化率为3.2%,产物MAA选择性为95%.  相似文献   

12.
Different approaches for the synthesis of 1-benzyloxypyrazin-2(1H)-one derivatives from simple amino acids have been investigated. A library of 33 precursors for the preparation of N-hydroxy pyrazinones was obtained in moderate to good yields.  相似文献   

13.
In the context of the preparation of camptothecin and luotonin A analogs, the synthesis of some key keto-precursors and their use in Friedländer condensation are described. This paper also focuses on the stability of these keto intermediates and emphasizes the major differences between indolizinones and pyrroloquinazolinones series. Noteworthy is also the report of some original structures isolated as by-products of some experiments.  相似文献   

14.
The Langevin paramagnetic theory can’t describe the relation between magnetization of ferrofluids and applied magnetic field. The structuralization of ferrofluids, which is considered the main influence factor of the magnetization, is regarded. The part of magnetization works is deposited when the structure is forming. This action influences the magnetization of ferrofluids directly or indirectly. On the base of the “compressing” model, the Langevin function that usually describes the magnetization of ferrofluid is modified, and a well-fitted curve is obtained. An equation of the relation between the equivalent volume fraction after being “compressed” and the intensity of magnetic field is discovered, which approximately describes the process of magnetization. The relation between the approximate initial susceptibility and the volume fraction can be obtained from modified formula.  相似文献   

15.
The highly regioselective Buchwald–Hartwig amination at C-2 of the cheap and readily accessible reagent, 2,4-dichloropyridine with a range of anilines and heterocyclic amines is described. This new methodology is robust and provides a facile access to 4-chloro-N-phenylpyridin-2-amines on 0.25 mol scale. These intermediates undergo a further Buchwald–Hartwig amination at higher temperature to enable rapid exploration of the chemical space at C-4 and to provide a library of 2,4-bisaminopyridines.  相似文献   

16.
KMnO4-mediated oxidative CN bond cleavage of tertiary amines producing secondary amine was introduced, which was trapped by electrophiles (acyl chloride and sulfonyl chloride) to form amides and sulfonamides. The reaction could take place at mild condition, tolerating a wide range of function groups and affording products in moderate to excellent yields.  相似文献   

17.
The review contains a concise historical account and information on the most significant researches undertaken by the staff at the A. E. Favorsky Irkutsk Institute of Chemistry, Siberian Branch of the Russian Academy of Sciences on the Chemistry of Heterocyclic Compounds. Dedicated to Academician of the Russian Academy of Sciences B. A. Trofimov on his 70th jubilee. Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 10, pp. 1443–1502, October, 2008.  相似文献   

18.
A general synthesis of previously unknown semicarbazone-based α-amidoalkylating reagents, 4-(tosylmethyl)semicarbazones, has been developed. The synthesis involved three-component condensation of semicarbazones of aliphatic or aromatic aldehydes with the same or other aldehydes and p-toluenesulfinic acid. The scope and limitations of this reaction were investigated. The compounds obtained were demonstrated to be an efficient α-(4-semicarbazono)alkylating agents. They were reacted with H- (sodium borohydride), O- (sodium methylate), S- (sodium phenylthiolate), N- (pyrrolidine, sodium succinimide), P- (trialkyl phosphites), and C-nucleophiles (sodium diethyl malonate) to give the corresponding products of the tosyl group substitution, 4-substituted semicarbazones, including analogues of nitrofurazone. Among the prepared compounds tested in vitro for antibacterial and antifungal activity, three nitrofuryl-containing semicarbazones exhibited high biological activities with minimum inhibitory concentration (MIC) values of 8–32 μg/mL.  相似文献   

19.
Zhanhui Yang  Shiyi Yang  Jiaxi Xu 《Tetrahedron》2017,73(23):3240-3248
Regiospecific and direct imidation of the methyl C(sp3)–H bond of thioanisoles is realized under mild and metal-free conditions with N-fluorobis(benzenesulfonyl)imide as an oxidant and nitrogen source. Proposed mechanism suggests that thionium ion intermediates and a Pummerer-type reaction are involved. The imidation has advantages such as high step-economy, excellent functionality tolerance, and regiospecificity, giving structurally diverse imidation products.  相似文献   

20.
A small library of new chiral bidentate hydroxyalkyl-imidazolium salts 1 is conveniently synthesized on multi-gram scale from inexpensive and commercially available chiral pool amino acids. The corresponding carbenes, generated by deprotonation of imidazolium salts 1, in combination with palladium(II) chloride were tested in the Mizoroki–Heck coupling reaction. The most significant results in terms of yields and reactivities were achieved with low catalyst loading. The catalytic activities of these imidazolium salts were also investigated in the asymmetric addition of diethylzinc to benzaldehyde. The use of MgO nanoparticles as an additive in conjunction with these ligands played a crucial role in increasing the efficiency of these reactions.  相似文献   

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