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1.
Three types of unit combinations, FeS2Fe + FeS2Fe, FeS2Fe + MoS2Fe and MoS2Mo + MoS2Mo, lead to Fe4S4, MoFe3S4 and Mo2Fe2S4 cubane-like clusters, respectively. A new doubly bridged single cubane cluster [Mo2Fe2S4(C4H8dtc)6]·3.5C2H2Cl4 has been obtained and its structure is discussed.  相似文献   

2.
1INTRODUCTIONThecoordinationchemistryofmanganeseinthe 2, 3and 4oxidationstatesisreceivingconsiderableattentionduetothebio1ogicalimportanceoftheseions(1i.Anattractivesystemformode1ingthestructureandreactivityofsomemanganoenzymesisbinuclearMn(M)complexescontainingpolydentateSchiffbaseligands.Bothphotochemicalwateroxidationtogeneratedioxygen"'andacid-pro-motedhydrogenperoxideproductiont3ihavebeenreportedforsuchdimer.Wereportherethestructureofthetitlecomplex.2EXPERIMENTAL2.lSynthesisof…  相似文献   

3.
<正> C10H10Cu2N6O4S2,Mr = 475. 41,monoclinic,space group P2/c,a = 8. 531 (2),b= 6. 870(1) ,c= 14. 463(2) A ,β=93. 84 (2), V= 845. 7 A3,Z=2,D = 1. 866 g·cm-3,μ=27. 799cm-1,F(000) = 484,R=0. 071. The molecules possesse basically a planar structure ,with the two aquamolecules displaced 2. 75 A to opposite sides of this plane and being at the apexpositions of the square pyramidal coordination of the two Cu atoms, respectively, the two carbonyls of the oxamide show the "trans-form".  相似文献   

4.
<正> The structures of two complexes C(CuOC6H4CH2NHCH2COO)2 (H2 O)]·H2P(1) and [Co(NH3)6[Co(OC6H4CH2NHCH2COO)2]2[C1]·10H2O (2) were determined by X-ray analyses. Compound (1) crystallizes in the orthorhombic space group P212121 with a=11. 357(1),b= 24. 304(2),c=7.317(4) A,Z= 4;While compound (2) in the monoclinic space group A2/a(C2/c) with a=23. 486(9) ,b=26. 605(6) ,c= 10. 542(1) A,γ= 128. 42(4)°,Z= 4. In compound (1),two Cu(Ⅱ) ions are bonded together by the phenolic oxygen atoms of two tridentate chelating ligands and each of them is separately coordinated by the carboxyl oxygen,amino nitrogen of each chelate ligand and by the fifth oxygen atom as well (from aqua or the carbonyl group in adjacent molecule). Thus the coordination of each Cu(Ⅱ) is a square pyramid with distances of 1. 93- 1. 97A to the four corner atoms and 2. 30 and 2. 32 A to the apex atoms. The whole molecule has an approximately planar configuratioir with the two pyramid apexes pointing towards one side. Compound (2) consists of  相似文献   

5.
童庆松  杨勇  连锦明 《电化学》2005,11(4):435-439
以L iOH.H2O和Mn(CH3COO)2.2H2O作原料,应用微波-固相两段烧结法合成具有L i4Mn5O12结构特征,组成为L i3.22Na0.569Mn5.78O12.0的锂离子电池正极材料.XRD分析表明,在380℃的后处理温度下,微波烧结前处理有利于生成纯L i4Mn5O12尖晶石相.充放电实验表明,在4.5~2.5V电压区间,新制样品的初始放电容量为132 mAh.g-1,100循环的容量衰减率为6.8%;4个月存放样的初始放电容量为122 mAh.g-1,100循环的容量衰减率为17.4%.表现出较好的充放电性能和循环寿命.微波烧结使样品的Mn-O键被加强.  相似文献   

6.
化石燃料的使用排放了大量CO_2,对气候和环境造成了日益严重的危害.固体氧化物电解池(SOEC)能够利用可再生能源产生的电能将CO_2高效转化成CO,降低CO_2排放的同时,又能减少化石燃料的使用,近年来受到研究者的广泛关注.相比于低温液相CO_2电还原,SOEC高的运行温度保证了其较高的反应速率,即较高的电流密度.典型的SOEC单电池由多孔阴极、致密电解质和多孔阳极以三明治的方式组装而成.CO_2分子在阴极得到两个电子解离成CO和一个O_2~-;生成的O_2-通过致密电解质传导至阳极,在阳极失去四个电子发生析氧反应(OER)生成一个O_2.相比于两电子的阴极反应,阳极四电子的析氧反应更难进行,可能是整个电极过程的速控步,因此开发高性能的阳极材料有望显著提高SOEC的CO_2电还原性能.La_(0.6)Sr_(0.4)Co_(0.2)Fe_(0.8)O_(3-δ)(LSCF)因具有较高的混合离子-电子导电性而被用作SOEC阳极材料,但受LSCF-气体两相界面的限制,其OER性能较低.研究表明,LSCF-掺杂的Ce O2-气体所构成的三相界面相比于LSCF-气体两相界面具有更高的电化学反应活性,即OER反应更易在三相界面进行.因此,本文将Gd_(0.2)Ce_(0.8)O_(1.9)(GDC)纳米颗粒浸渍到SOEC LSCF阳极来提高其OER活性,考察了纳米颗粒浸渍量(3,5,10和20 wt%)对SOEC电化学性能的影响.结果表明,SOEC的电化学性能随浸渍量的增加而逐渐升高,当GDC纳米颗粒浸渍量为10 wt%时(10GDC/LSCF),SOEC的电化学性能达到最高,在800 oC和1.6V的电流密度为0.555 A cm~(-2),是LSCF阳极SOEC性能的1.32倍.继续增加浸渍量到20 wt%,电化学性能反而开始下降.电化学阻抗谱测试结果表明,GDC纳米颗粒的加入减小了SOEC的极化电阻.对应的弛豫时间分布函数解析结果表明10GDC/LSCF阳极上的OER由四个基元反应构成.电镜和O_2~-程序升温脱附结果表明,GDC纳米颗粒的加入显著增加了10GDC/LSCF阳极三相界面和表面氧空位的数量以及体相氧的流动性,从而促进了OER四个基元反应的反应速率,降低了这几个过程的极化电阻,因而降低了OER反应的极化电阻,提高了SOEC电还原CO2的电化学性能.  相似文献   

7.
<正> (Et4N)[Ni2(SC6H5)2(S2CS)2],Mr= 844. 68; monoclinic P21/c, a = 16. 951(3), b = 11. 151(3), c=20. 428(2)(?) ,β=99. 03(2)°, V = 3813(3)(?)3, Z = 4, Dm = l. 48, Dx = 1. 471 gem-3, graphite-monochromated MoKa=0. 71073 (?), μ=14. 4cm-1, F(000) = 1776; T' = 295K, R = 0.061, Rw =0.072 for 5586 unique observed reflections, and 211 parameters. The structure of the complex consist of discrete [Ni2(μ-SC6H5)2(S2CS)2]2- complex anions and tetraethylammonium cations. In each anion nickel (Ⅱ) is distorted square planar coordinated with four atoms, two bridging atoms from the benzene-thiolato and two from the trithio-car-bonate, SCS22- ligand. The structure has the synendo conformation[1].  相似文献   

8.
<正> [K(C_12H_24O_6)]_2Pd(SCN)_4(H_2O),MT=963.59,monoclinic, P21/n,a= 11. 075(1),b= 12. 231(1),c= 15. 863(2) A ,β=93. 25(1)°,V=2145. 3A3,Z=2, Dc=1. 492gcm-3,λ(MoKa) = 0. 71073A μ=8. 64cm-1,F(000) = 996,final R=0. 045 for 1835 observable reflections. The Pd2+ ion coordinates with four S atoms from SCN- groups forming a regular square planar configuration. The K+ ion is surrounded by six ether oxygen atoms,one O atom from water molecule coordinated to two K+ions and one N atom from SCN- group to form a distorted hexagonal bipyramid. Two K atoms are linked with one Pd atom by two bridging SCN- groups forming a chain molecular array in the crystal.  相似文献   

9.
通过简单取代反应,合成了一个新的混金属簇合物(μ3-S)FeCo2(CO)7(dppfe)(2)(dppfe=Ph2PC5H4FeC5H4PPh2).利用IR,1HNMR,MS和X-ray单晶衍射的方法对簇合物2进行了结构表征.簇合物2的晶体属于三斜晶系,空间群为Pī.晶胞参数:a=1.1324(15)nm,b=1.3670(17)nm,c=1.5769(2)nm,α=114.646(2)°,β=100.340(2)°,γ=100.113(3)°,V=2.0953(5)nm3.  相似文献   

10.
(μ3-S)FeCo2(CO)7(dppfe)的合成和晶体结构   总被引:1,自引:0,他引:1  
通过简单取代反应,合成了一个新的混金属簇合物(μ3-S)FeCo2(CO)7(dppfe) (2) (dppfe=Ph2PC5H4FeC5H4PPh2).利用IR,1H NMR,MS 和 X-ray单晶衍射的方法对簇合物2进行了结构表征.簇合物2的晶体属于三斜晶系,空间群为Pī.晶胞参数: a=1.132 4(15) nm, b=1.3670(17) nm, c=1.5769(2) nm,α=114.646(2)°,β=100.340(2)°,γ=100.113(3)°, V=2.0953(5) nm3.  相似文献   

11.
In this work, we studied the catalytic activity of LaMnO3 and(La0.8A0.2)MnO3(A = Sr, K) perovskite catalysts for oxidation of NO and C10H22 and selective reduction of NO by C10H22. The catalytic per‐formances of these perovskites were compared with that of a 2 wt% Pt/SiO2 catalyst. The La site substitution increased the catalytic properties for NO or C10H22 oxidation compared with the non‐substituted LaMnO3 sample. For the most efficient perovskite catalyst,(La0.8Sr0.2)MnO3, the results showed the presence of two temperature domains for NO adsorption:(1) a domain corre‐sponding to weakly adsorbed NO, desorbing at temperatures lower than 270 °C and(2) a second domain corresponding to NO adsorbed on the surface as nitrate species, desorbing at temperatures higher than 330 °C. For the Sr‐substituted perovskite, the maximum NO2 yield of 80% was observed in the intermediate temperature domain (around 285 °C). In the reactant mixture of NO/C10H22/O2/H2O/He,(La0.8Sr0.2)MnO3 perovskite showed better performance than the 2 wt% Pt/SiO2 catalyst: NO2 yields reaching 50% and 36% at 290 and 370 °C, respectively. This activity improvement was found to be because of atomic scale interactions between the A and B active sites, Sr2+ cation and Mn4+/Mn3+ redox couple. Thus,(La0.8Sr0.2)MnO3 perovskite could be an alternative free noble metal catalyst for exhaust gas after treatment.  相似文献   

12.
A bimetallic complex Ni[C10H8N2]3[ZnCl4] has been synthesized and its crystal structure determined at room temperature. The complex crystallizes in the trigonal system, space group R3c, with a = 13.343(2), b = 13.343(2), c =58. 932(12) A, V= 9087(3) A 3, Z = 12, NiZnC30N6CI14H24, Mr=734.30, Dc=1.611 g/cm3, μ= 1. 799 mm-1, F(000)=4464. Least-squares refinement of the structure leads to the agreement factors R1=0. 0278 and wR2=0. 0741 for the observable reflections. The complex consists of discrete tris (2, 2'-bipyridine) nickel (Ⅱ)cation, [Ni-(bipy)3]2+, and tetrachlorozincate anion, [ZnCl4]2-. Each nickel (Ⅱ)atom is six coordinated in an octahedron with six nitrogen atoms of three 2,2'-bipyridine ligands. The mean Ni(Ⅱ)-N bond length is 2. 089(2) A. The zinc(Ⅱ) atom is coordinated with four chloride atoms in tetrahedral geometry. The mean Zn (Ⅱ)- Cl bond length is 2. 264(1) A.  相似文献   

13.
<正> The title crystal belongs to monoclinic system, space group P21/c, with 3=14.794(2), b=7.360(1), c=16.029(2) A, β=94.95(2)0, Z=4, V=1738.9(6)A3, Dx=1.735 g/cm3. The final R=0.047, Rw=0.052.  相似文献   

14.
隔膜和熔融碳酸盐燃料电池 (MCFCS)性能的研究(英文)   总被引:6,自引:1,他引:5  
用γ LiAO2 粉料和带铸法制备电池隔膜。隔膜有很高的阻窜能力和较低的欧姆极化。在电流密度为 2 0 0和 2 4 6mA/cm2 下放电时 ,用此膜组装的电池组 (三对电池 ,电极面积为 12 2cm2 )输出电压分别为 2 .0 1和 1.78V ,输出功率达 53.4W .于 2 0 0和 30 0mA/cm2 下放电时 ,单电池 (电极面积为 2 8cm2 )输出电压分别高于 0 .85和 0 .75V ,输出功率约 6 .6W .补偿隔膜收缩导致电池性能的提高 .  相似文献   

15.
By a proper thermal treatment, the nitrogen atoms can enter the R2Fe17 structure. The crystallographic and intrinsic magnetic properties as well as their relationship have been studied by magnetic measurements, X-ray and neutron diffraction techniques. The neutron data indicate that the nitrogen atoms occupy the interstitial sites in the Th2Zn17-type rhom-bohedral structure. The inserting nitrogen atoms are found to dilate the cell volume, increase the Curie temperature and enhance the saturation moment by raising the difference in the electron number between the spin-up and spin-down 3d subbands of the Fe atoms. Furthermore, the nitrogen atoms have an important effect on the magnetocrystallic anisotropy, which results in an easy axis with Sm2Fe17N2.4. All these make Sm2Fe17N2.4 favorable for permanent magnet applications.  相似文献   

16.
<正> The reaction of Fe3(CO)12 with P(SPh)3 yields the tile compound. C41H30Fe2O5P2S6, Mr = 968. 65, monoclinic, space group, P21/n, a = 14. 449(9), b = 18. 046(11), c=16.871(10)(?), β=98. 76°, V = 4348(?)3, Z = 4, Dc=1. 480g/ cm3, λ(MoKα) = 0. 71073(?) The structure was determined by direct methods and difference Fourier syntheses and refined by full-matrix least-squares procedure to R = 0.084, Rw = 0.144 for 4059 reflections. Fe(1)-Fe(2) = 2. 576(6), Fe(2)-P(2) = 2.194(9)(?). The dihedral angle between the Fe(l)SFe(2) and Fe(1)PFe(2) planes is 81. 9°. The other one (dihedral angle between SFe(1)P and SFe(2)P planes) is 75. 2°.  相似文献   

17.
The title compound was synthesized by the reaction of cis-[Co(phen)2Cl2]Cl·3H2O with DL-alanine at pH = 8, and isolated using a column chromatographic method. Its crystal structure was determined. The crystal structure belongs to mono-clinic system, space group P21/c, with a = 0. 9549(6) nm, b=2.3746(8) nm, c= 1.0782(4) nm, β=114.13(3)°? Z = 4, Dc= 1. 50 g/cm3. The final refinement converged to R = 0. 047 for 3246 independent observed reflections. In the octahedral coordination sphere formed by the cobalt atom and the coordinate atoms, N, O of DL-alan-inato ligands are in the configuration of trans-N ,N form.  相似文献   

18.
Kaerophyllin (1) ,hinokinin (2 )andtheiranalogue isohinokinin (3)belongtothedibenzylbutyrolactone lig nans .Kaerophyllin (1)wasisolatedfromtherootofspot tedcowparsley (ChaerophyllummaculatumWilld .) 1andhinokinin (2 )wasisolatedfromtheheartwoodofLiboce drusformosanaFlorin .2 AccordingtoMacRaeandTow ers ,3afivememberedlactoneringandamethylenedioxylgroupwereimportantstructuralcharacteristicswhichcon tributetotheactivityoflignansasantitumoragents .More over ,anunsaturateddoublebondbetweenC3—…  相似文献   

19.
以LiOH·H2O、Ni2O3、Co2O3、TiO2和Mg(OH)2为原料,应用固相反应法合成Co Ti Mg共掺杂的LiNiO2化合物LiNi0. 85Co0. 10 (TiMg)0. 025O2;TG DTA、XRD、SEM和电化学测试表明,该材料首次放电容量达182. 7mAh/g(3. 0~4. 3V, 18mA/g), 10次循环之后,容量还有 175. 5mAh/g,容量保持率为 96. 2%;与未掺杂的LiNiO2相比,该材料显示出良好的循环性能,是一种很有应用前景的锂电池正极材料.  相似文献   

20.
研究经NaOH处理了的MmNi3.2Al0.2Mn0.6Co1.0,再应用电沉积法制备Au改性的MmNi3.2Al0.2Mn0.6Co1.0催化剂对NaBH4的电催化氧化性能.SEM观察催化剂样品的微观形貌,线性伏安扫描法测定其电催化氧化性能,发现Au-MmNi3.2Al0.2Mn0.6Co1.0电极电催化氧化NaBH4电流密度为60 mA.cm-2,比在MmNi3.2Al0.2Mn0.6Co1.0电极的增加3.5倍.若对该电极在电解质中预浸泡10 h,则氧化电流密度可达到184 mA.cm-2.  相似文献   

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