首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 93 毫秒
1.
纳米Mn-Zn铁氧体的制备和研究   总被引:10,自引:0,他引:10  
Nanosize manganese zinc ferrites were fabricated by hydrothermal precipitation route using Fe2(SO4)3, ZnSO4·7H2O, MnSO4·H2O as material, then some calcinated at 500 ℃ and studied by XRD, TEM, IR and VSM. The results showed that the products were spinel crystal structure and uniformly sized nanoparticles (15~25 nm) with little aggregation. The analysis of IR showed that the superficial water can be eliminated, but that was embedded in crystal lattice can not be removed by calcinating. The effect Zn content x on the lattice (a) of nanosize Mn1-xZnxFe2O4 was also discussed. The lattice of nanosize Mn1-xZnxFe2O4 decreases with x increasing; and its value deviated the standard lattice (a0) of normal size manganese zinc ferrites. A lot of water was absorbed during the hydrothermal process owing to the large surface of nanosize particles. The change of magnetic properties of MnxZn1-xFe2O4 with x increasing was studied: nanosize MnxZn1-xFe2O4 particles synthesized by us exhibited peculiar magnetic properties curve with Zn content (x) increasing, Superparamagnetic behaviors of the synthesized ZnFe2O4 samples were confirmed by magnetic characterization, which can be explained by the difference between the distribution of the metal ions (Mn2+, Zn2+ and Fe3+) among the tetrahedral (A) and the octahedral (B) sites of nanosize ferrite and that of bulk ferrite.  相似文献   

2.
new coordination polymer {[Zn(CF3COO)2(C5H5ON)]·H2O}n was synthesized based on the reaction of zinc(Ⅱ) trifluoroacetate and 3-hydroxypyridine(C5H5ON) in methanol medium for the first time. The structure of the coordination polymer was confirmed by IR, 1H NMR, elemental analysis and thermal analysis. The crystal structure of the coordination polymer was also determined by X-ray single crystal diffraction. The crystal belongs to monoclinic system with space group P21/m, and crystallographic data of the coordination polymer are: a= 0.863 1(4) nm, b=0.717 7(3) nm, c=1.116 4(5) nm, α=γ=90°, β=107.542(6)°, V=0.659 4(5) nm3; Dc=2.037 g·cm-3; Z=2; F(000)=400; μ=1.969 mm-1. Zinc(Ⅱ) atom lies at the center of an octahedron formed by the coordination of zinc atom and six O atoms which come from four different trifluoroacetate ions and two different 3-hydroxypyridine molecules where each trifluoroacetate ion and 3-hydroxypyridine are coordinated to two different zinc ions to form coordination polymer. CCDC: 253909.  相似文献   

3.
LiNi1-xCoxO2 cathode materials for lithium ion batteries were synthesized by the co-precipitation and solid-state reaction methods with LiOH·H2O, Ni(NO3)2·6H2O and Co(NO3)2·6H2O as raw materials. The materials were characterized by XRD, SEM and electrochemical tests. The results showed that synthesized cathode materials were with layered structure similar to α-NaFeO2 and uniform morphology and nearly normal grain size distribution and better electrochemical performance when x was 0.18. The first charge and discharge capacity of the cathode material was 224.3 mAh·g-1 and 194.2 mAh·g-1, respectively. 88.5% of the first discharge capacity remained at the 20th cycle.  相似文献   

4.
L-苏糖酸锰的制备及标准生成焓   总被引:1,自引:0,他引:1  
The pink powder of manganese L-threonate was obtained by extracting with alcohol the concentrated solution derived from the reaction between L-threonic acid solution prepared by double decomposition reaction of calcium L-threonate with oxalic acid and superfluous manganese oxide at 80℃ for certain time. The composition of the new compound was determined by chemical and elemental analyses and its formula fits Mn(C4H7O5)2·H2O, the IR spectra indicated that Mn2+ in the compound coordinates to oxygen atom of the carboxyl group, while the proton of the carboxyl group is dissociated, it was assumed that the coordination number of Mn2+ was 4. The results of TG-DTG showed that the compound have fairish stability, the intermediate and final product of the thermal de-composition of the compound are Mn(C4H7O5)2 and MnO2, respectively. The constant volume combustion energy of the compound, ΔcE, were determined by a precise rotating-bomb calorimeter at 298.15K, it was (-3384.30±1.21)kJ·mol-1, its standard enthalpy of Combustion,ΔcHm?,and standard enthalpy of formation,ΔfHm? , were calculated. They are (-3383.07±1.21)kJ·mol-1 and (-2 571.68±1.63)kJ·mol-1, respectively.  相似文献   

5.
The complex [Zn(acac)2(C5H4NOH)] was synthesized based on the reaction of zinc(Ⅱ) acetate, acetylaceton and 3-hydroxypyridine(C5H4NOH) in methanol medium. The structure of the complex was confirmed by IR, 1H NMR, elemental analysis, thermal analysis and X-ray single crystal diffraction. The crystal belongs to monoclinic system with space group P21/n, and a=0.743 7(3) nm, b=0.829 5(3) nm, c=2.612 5(9) nm, β=95.026(6)°, V=1.605 4(9) nm3; Dc=1.484 g·cm-3; Z=4; F(000)=744; μ=1.551 mm-1. Zinc(Ⅱ) atom lies at the center of an coordination of the distorted square pyramidal formed by four O atoms which come from two different acetylaceton ions and one N atom from the 3-hydroxypyridine molecule. CCDC: 600232.  相似文献   

6.
 4-(3-(4-((4-Nitrophenyl)azo)phenyloxy)propyl)aminobenzene sulfonic acid (C3-ABSA) was synthesized by the reaction of 3-bromide-l-(4-((4-nitrophenyl)azo)phenyloxy)propane (B3) with sodium p-aminobenzene sulfonic acid (ABSA)and acidification with hydrochloric acid. The C3-ABSA was characterized by FTIR, 1H-NMR and second ion mass spectrum (SIMS). The molecular formula of dehydrated C3-ABSA was estimated to be ca. C21H20O6N4S by SIMS. Its decomposition temperature was measured by TGA to be ca. 232℃. It was found that tubular polyaniline (PANI) with a conductivity of 1.1 S/cm at room temperature was successfully synthesized by in-situ doping polymerization in the presence of C3-ABSA as a dopant.  相似文献   

7.
Complex [Co(HOC10H6COO)2(H2O)4] was synthesized by reaction of hydroxy-2-naphthoic acid with CoCl2·6H2O. The compound was characterized by elemental analysis, IR and the structure was determined by single-crystal X-ray diffraction. The crystal belongs to monoclinic, space group P21/n with a=0.675 8(2) nm, b=0.518 15(14) nm, c=2.962 9(9) nm, β=94.925(8)°. V=1.033 6(5) nm3, Z=2, D=1.624 Mg·m-3, F(000)=522. The Co atom has an octahedron coordination geometry and was six-coordinated with two oxygen atoms from two carboxylate ligands and four oxygen atoms from four water molecules. The complex molecules were linked by different hydrogen bonds to form a 2D network. The complex has thermal stability and shows a strong fluorescent emission at 421 nm (λex=342 nm). CCDC: 250903.  相似文献   

8.
Four ternary solid complexes were synthesized with sodium diethyldithiocarbamate (NaEt2dtc)(b), 1,10-phenanthroline (o-phen) (c) and hydrated lanthanide chlorides in absolute ethanol by an improved reported method. The complexes were identified as the general formula of RE(Et2dtc)3(phen) (RE=La, Pr, Nd, Sm) by chemical and elemental analyses. IR spectra of the complexes showed that the RE3+ was coordinated with sulfur atoms of NaEt2dtc and nitrogen atoms of o-phen. The constant-volume combustion energies of complexes, ΔcU, were determined by a precise rotating-bomb calorimeter at 298.15 K. The standard enthalpies of combustion, ΔcHm?, and standard enthalpies of formation, ΔfHm?, were calculated for these complexes, respectively.  相似文献   

9.
钾的N-酰化牛磺酸配合物的合成、表征及其晶体结构   总被引:3,自引:0,他引:3  
The title complex(K(C9H13NO5S2)(H2O)) was synthesized by the reaction of p-tolysulfonyl chloride, taurine and potassium hydrate in water-methanol-ethanol solution. The crystal structure was determined by X-ray diffraction method and the chemical formula weight of the complex is 336.44. The crystal structure of the title complex belongs to orthorhombic space group Pbca and cell parameters: a=0.853 31(12) nm, b=0.820 42(12) nm, c=3.989 4(6) nm. V=2.792 8(7) nm3, Z=8, Dc=1.600 g·cm-3, μ=0.699 mm-1, F(000)=1 400. The compound is an one-dimension chain complex of infinite length which are connected with hydrogen bond and bridging coordination water. The difference and same of the complexes were discussed. CCDC: 244938.  相似文献   

10.
The complex {[Co(4,4′-bpy)(H2O)4](Fum)·4H2O}n(where 4,4′-bpy = 4,4′-bipyridine and Fum = fumarate) was synthesized and characterized by X-ray diffraction. The complex consists of one-dimensional chains containing cobalt(Ⅱ) ions bridged by 4,4′-bpy molecules. The six-coordination of Co2+ is achieved by means of four water molecules. The fumarate is not coordinated to cobalt ion while it forms hydrogen bonds with coordinated and non-coordinated water molecules and extends the structure into three-dimensional hydrogen bonding network. CCDC: 190488.  相似文献   

11.
The reaction of optically active Halterman porphyrin with sulfuric acid (95%) provided the expected water-soluble para-tetrasulfonated porphyrin in 82% yield. The metalloporphyrin complexes were prepared by metal insertion (iron) or direct sulfonation of the chiral ruthenium porphyrin. The asymmetric addition of diazoacetate to styrene to give optically active trans cyclopropyl ester (ee up to 86%) was carried out in water by using chiral iron or ruthenium porphyrins with a possible reuse due to the high solubility and stability in aqueous solution.  相似文献   

12.
木文报道了钴(Ⅱ,Ⅲ)与meso-四(4-苯基磺基)卟啉(TPPS)络合物的形成条件和电还原行为.结果表明在醋酸缓冲溶液(pH3.5)中,Co2+-TPPS还原同时产生催化氢波.在氨性缓冲溶液(pH9.0)中,Co2+-TPPS产生络合吸附波,讨论了其伏安行为,认为络合物中Co2+和TPPS是一步同时还原.溶解氧可以把Co2+-TPPS氧化为Co3+-TPPS,对比Mn3+-TPPS讨论了络合物的形成和溶解氧的作用,认为氧对卟啉络合物中心离子价态变化和电子转移起着重要作用.  相似文献   

13.
以二甲基甲酰胺为溶剂,5-对氨基苯基-10,15,20-三苯基卟啉与苯甲醛直接反应得到一种不对称希夫碱卟啉化合物,并合成了它的稀土配合物.用元素分析、紫外-可见光谱、红外光谱1、H核磁共振以及X射线光电子能谱对这些化合物进行了表征,推测了稀土乙酰丙酮卟啉配合物的结构,稀土离子与乙酰丙酮的两个O原子和卟啉的4个吡咯N原子配位,配位数为6,稀土离子位于卟啉平面的上方.  相似文献   

14.
扈靖  刘彦钦  韩士田 《应用化学》2012,29(5):608-610
以二环己基碳二亚胺为脱水剂,meso-四(对羟基苯基)卟啉与5-氟尿嘧啶-1-基乙酸反应,合成了一种新型meso-四[4-(5-氟尿嘧啶-1-基乙酰氧基)苯基]卟啉化合物(A),产率12.7%;将其与乙酸锌反应得到其锌配合物(B),产率30.8%。 通过1H NMR、IR、MS、UV-Vis及元素分析确证了卟啉化合物A及其锌配合物B的结构。  相似文献   

15.
16.
17.
合成了几种卟啉单体和卟啉二聚体, 并测定了它们的三阶光学非线性的吸收系数(β)、折射率(n2)以及极化率(χ(3)), 对比研究了卟啉周边取代基及桥连基团的不同对三阶光学非线性的影响. 实验结果表明非线性极化率随卟啉大环电子云密度的增加而增大.  相似文献   

18.
The new six-coordinate complexes (TPP)Fe(Gly-OMe)2 C50H42FeN6O4 and (TPP)Fe(β-Ala-OMe)2 (C52H46FeN6O4) wbere TPP=meso-tetraphenyl porphyrinate, Gly-OMe=glycine methyl ester, β-Ala-OMe=β-alanine methyl ester and five-coordinte complex (TPP)Mn(Ⅱ)(Gly-OMe) (C47H35MnN5O2) have been prepared by sodium borohydride method.These complexes were characterized by UV-Vis, IR, ESR, spectra and by elemental analysis. The synthesized divalent iron porphyrins are d6 low spin states and their UV-Vis spectra are Hypso type; while divalent manganese porphyrin is d5 high spin state and its UV-Vis spectrum is pseudo-Normal type.  相似文献   

19.
20.
卟啉在结构上可视为是由4个吡咯类亚甲基的α-碳原子通过次甲基桥互联而形成的大分子杂环化合物,具有高度共轭结构。 随着卟啉与金属的配合物即金属卟啉的催化特性受到广泛关注,取代卟啉的高效合成日益显示出重要的学术和应用价值。 但是现有的丙酸法和乙酸/硝基苯法存在卟啉收率低、环境污染严重等问题,导致取代卟啉的成本居高不下,限制了其广泛应用。 本文利用乙酸/氧气法,在120 ℃下控制反应物浓度为0.24 mol/L,并在反应第一阶段(前30 min)通入氧气,得到四(4-溴苯基)卟啉(化合物d),产率高达53.8%。 该方法是高效合成取代卟啉的新方法,卟啉骨架形成和氧化两个反应同时进行,方法简单、绿色且收率高,有望大幅度降低取代卟啉的合成成本。  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号