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1.
采用固相反应合成出链状结构的稀土硼酸盐Eu(BO2)3发光材料。分别利用XRD、TEM、SAED、EDS和PL等测试技术对产物进行了研究,结果表明:链状结构的Eu(BO2)3属于单斜晶系,空间群为I2/a,直径约10~15nm,长度达几个微米,探讨了链状Eu(BO2)3的生长机理。在395nm紫外光激发下,Eu(BO2)3能发出Eu3+的特征红色荧光,发射主峰位于591nm,归属于5D0→7F1磁偶极跃迁。  相似文献   

2.
张兰英  张国 《应用化学》1991,8(6):95-97
淀粉改性官能团化作为金属离子的吸附剂用于废水处理已有报道,但吸附效果不理想,应用范围受限制。本文将玉米淀粉接枝甲基丙烯酸缩水甘油酯共聚物(Cs-g-PGMA)与甘氨酸反应,得到Cs-g-PGMA-Gly作为吸附剂,可以去除水中的Cd~(2 )、Cr~(3 )等有害元素,而且在适当的pH条件下还可富集分离Au~(3 )、Pd~(2 )。  相似文献   

3.
以Fe2O3为铁源原料, 利用热还原法成功地制备了LiFePO4/C复合材料. 用XRD以及SEM对材料的晶体结构以及表面形貌进行了表征. 通过循环伏安和充放电测试研究了材料的电化学性能. 研究结果表明, 于700 ℃下制备的LiFePO4/C复合材料在0.1C的倍率下可以得到放电容量144.8 mA·h/g, 在循环160次后, 容量仍保持在141.4 mA·h/g. 这种以廉价的Fe2O3代替目前常用的二价铁盐原料方法, 具有减少LiFePO4合成成本的优点.  相似文献   

4.
吴达旭  施继成 《结构化学》1998,17(6):395-399
对含手性膦配体甲基-3-脱氧-3-(二苯膦基)-4,6-氧-苄叉基-a-D-吡喃阿卓糖苷(3-MBPA)和甲基-2-脱氧-2-(二苯膦基)-4,6-氧-苄叉基-a-D-吡喃阿卓糖苷(2-MN-PA)及邻巯基氧化吡啶配体mpo的金配合物An[(3-MBPA)(mpo)](1)、An[(2-MBPA)(mpo)](2)和钯配合物Pd[(3-MBPA)(mpo)C1](3)、Pd[(2-MBPA)(mpo)-C1](4)进行1H和13CNMR谱测定,利用一维和二维NMR技术归属了所有的1H和13CNMR谱线,结果表明:配体MBPA与金属配伍的是P原子,糖苷上H-5的化学位移变化最大,而且与配位金属的种类有关;配体mpo以单齿形式与金属配位时,是S原子参与配位。  相似文献   

5.
偏磷酸钾制备方法研究   总被引:2,自引:0,他引:2  
偏磷酸钾是一种较理想的无氯磷钾复合肥。目前,制备偏磷酸钾的工艺主要有两种:①以磷酸和氯化钾为原料制备;②以元素磷和氯化钾为原料制备。此两种方法反应温度都较高,设备需要用特殊材质制造,副产物均有氯化氢气体,严重腐蚀设备,污染环境。为了克服这些不足,我们探索出了制备偏磷酸钾的新方法一磷酸二氢铵和氯化钾热复分解升华法。  相似文献   

6.
Two synthetic methods leading to the new n , n '-diphosphonylketones 2 and 2 ' are reported. The first method involves the base-catalyzed addition of diethylphosphite to diarylideneketones. The second one utilizes the reaction of triethylphosphite and ethoxydiphenylphosphine with g , g '-bis(dimethylamino)ketone hydrochlorides. On reaction with phenylhydrazine hydrochloride, compounds 2 and 2 ' give the corresponding 2-(phosphonoethyl)3-(phosphonomethyl)indoles 3 . The structure of all obtained products is confirmed by NMR ( 1 H, 31 P, 13 C) and IR spectroscopy.  相似文献   

7.
We have developed a facile and efficient method for the synthesis of functionalized novel furylquinolines. A variety of quinoline–furan conjugates were obtained via the condensation of 2-chloroquinoline-3-carbaldehyde with acetylenecarboxylates and isocyanides in good to excellent yields.  相似文献   

8.
Despite the strong technological importance of lanthanide complexes, their formation processes are rarely investigated. This work is dedicated to determining the influence of synthesis parameters on the formation of [Ce(bipy)2(NO3)3] as well as Ce3+‐ and Tb3+‐substituted [La(bipy)2(NO3)3] (bipy = 2,2′‐bipyridine) complexes. To this end, we performed in situ luminescence measurements, synchrotron‐based X‐ray diffraction (XRD) analysis, infrared spectroscopy (IR), and measured pH value and/or ion conductivity during their synthesis process under real reaction conditions. For the [Ce(bipy)2(NO3)3] complex, the in situ luminescence measurements initially presented a broad emission band at 490 nm, assigned to the 5d→4f Ce3+ ions within the ethanolic solvation shell. Upon the addition of bipy, a red shift to 700 nm was observed. This shift was attributed to the changes in the environment of the Ce3+ ions, indicating their desolvation and incorporation into the [Ce(bipy)2(NO3)3] complex. The induction time was reduced from 8 to 3.5 min, by increasing the reactant concentration by threefold. In contrast, [La(bipy)2(NO3)3] crystallized within days instead of minutes, unless influenced by high Ce3+ and Tb3+ concentrations. Monitoring and controlling the influence of the reaction parameters on the structure of emissive complexes is important for the development of rational synthesis approaches and optimization of their structure‐related properties like luminescence.  相似文献   

9.
Organometallic Compounds with N -substituted 3-Hydroxy-2-methyl-4-pyridone Ligands: square planar Rhodium(I), Iridium(I), and Palladium(II) Complexes Reactions of [(OC)2MCl]2 (M = Rh, Ir) or [(cod)RhCl]2 with the anions of N-Aryl or N-Alkyl substituted 3-hydroxy-2-methyl-4-pyridones (O–O′) yield complexes of the general formula [L2M(O–O′)]. Compounds of this type are also available from reactions of [(OC)2Rh(acac)] with the corresponding neutral ligands. Substitution of one carbonyl-ligand of the N-phenyl complex [(OC)2Rh(C12H10NO2)] ( 2 ) with cyclooctene affords [(OC)(C8H14)Rh(C12H10NO2)] ( 8 ). The palladium complexes [(R3P)Pd(O–O′)Cl] (R = Et, Bu), [(C6H4CH2NMe2) · Pd(O–O′)] and [(Et3P)2Pd(O–O′)]BF4 ( 9 – 12 ) were synthesized from [(R3P)PdCl2]2, [(C6H4CH2NMe2)PdCl]2 or [(Et3P)PdCl2]. The structures of the N-methyl compounds [(OC)2Rh(C7H8NO2)] ( 1 ) and [(Ph3P)Pd(C7H8NO2)Cl] ( 9 ) were determined by single crystal X-ray diffraction.  相似文献   

10.
11.
本文将纳米氧化铝微柱分离系统与石墨炉原子吸收光谱法联用,用于测定环境水样中的痕量铅和镉。较系统地考察了纳米Al2O3材料对镉和铅离子的吸附性能及影响因素;在优化的实验条件下本法对Pb和Cd的检出限(3σ)分别为0.189 ng/mL和0.0039 ng/mL;RSD%分别为3.9%和2.9%。  相似文献   

12.
《合成通讯》2013,43(4):735-742
Abstract

An easy and generalized route to 2(3H)‐benzimidazolones, 2(3H)‐benzoxazolone and 2(3H)‐benzothiazolone is attempted. A novel one‐pot method for the in situ generation and cyclisation of ortho substituted benzoic acid azides is reported via the application of ammonium azide and Vilsmeier complex.  相似文献   

13.
应用以氢氧化物共沉淀为前驱体的高温固相烧结法合成L iN i1/3Mn1/3Co1/3O2正极材料,研究了沉淀温度及烧结过程锂盐投入量对该材料的结构和电化学性能的影响.结果表明,以室温(~20℃)下合成的氢氧化物为前驱体制备的L iN i1/3Mn1/3Co1/3O2具有较好的电化学性能.高温固相烧结会导致部分L iOH损失,因而在合成过程中需加入过量的氢氧化锂,实验表明L i1.08N i1/3Mn1/3Co1/3O2材料的电化学性能最优.  相似文献   

14.
A series of metal(II) complexes ML and ML2 [where M?=?Cu(II), Co(II), Ni(II), Zn(II), Mn(II), Cd(II), and VO(II); L?=?2-hydroxyphenyl-3-(1H-indol-3-yl)-prop-2-en-1-one (HPIP)] have been prepared and characterized by elemental analysis, magnetic susceptibility, molar conductance, IR, UV-Vis, NMR, Mass, and ESR spectral studies. Conductivity measurements reveal that the complexes are non-electrolytes, except VO(II) complex. Spectroscopy and other data show square pyramidal geometry for oxovanadium and octahedral geometry for the other complexes. Redox behavior of the copper(II) and vanadyl complexes has been studied with cyclic voltammetry. Antimicrobial activities against several microorganisms indicate that a few complexes exhibit considerable activity. The nuclease activity shows that the complexes cleave DNA. All synthesized compounds can serve as potential photoactive materials as indicated from their characteristic fluorescence properties. The second harmonic generation efficiency of the ligand is higher than that of urea and KDP.  相似文献   

15.
On the Structure of Sr3(BN2)2 The structure of Sr3(BN2)2 was determined on single-crystal X-ray data collected with a four-circle diffractometer. Sr3(BN2)2 crystallizes in the cubic space group Im3 m (no. 229) with a = 764.56(3) pm and Z = 3. The structure contains linear BN3?2 ions with a B? N bond length of 135.8(6) pm. The straight forward synthesis employing metal nitrides plus boron nitride yielded crystalline powders of M3(BN2)2 (M = Ca, Sr) at 1100°C (5 days). Cubic indexing of guinier patterns gave a = 765.8(1) pm for M = Sr and a = 734.7(2) pm for M = Ca. The structure refinement on a single crystal of Sr3(BN2)2 revealed that one strontium site (2a; 0, 0, 0) is occupied by only about 50%. It has been tried to fully occupy this site with an alkali metal (A) to obtain ASr4(BN2)3 (Z = 2). Reactions with A = Na yielded crystalline powders. Cubic indexing of the guinier pattern analogous to that of Sr3(BN2)2 gave a = 754.2(1) pm.  相似文献   

16.
A New Tricyclic Sulfur-rich Phosphane From the products of the reaction of P4S3 with tert-Butyliodide the compound (t-Bu(S)P)2P4S3 was isolated in low yield. The compound is stable and has a structure related to the hydrocarbon brexane. By reaction with triphenylphosphin the compounds (t-BuP)(t-Bu(S)P)P4S3 and (t-BuP)2P4S3 were obtained. The 31P-nmr spectra of all compounds were solved and used to determine the structure of the molecules. A complete set of 31P-nmr data is given.  相似文献   

17.
利用电化学和紫外光谱法研究了邻菲咯啉合钴(Co(phen)2+3)与普利沙星(PLFX)及DNA间在pH=7.4的三羟甲基氨基甲烷-盐酸缓冲溶液中的结合作用. 紫外光谱测量结果表明,普利沙星与Co(phen)2+3发生了结合作用形成二元络合物,结合常数为2.0×104 L/mol. 电化学测量表明,在Co(phen)2+3-普利沙星络合物中加入DNA后,Co(phen)2+3-普利沙星络合物的峰电流下降,峰电位差增大了17 mV,式电位负移了3.5 mV,推断络合物与DNA作用方式主要为静电作用.  相似文献   

18.
INDO方法研究了C70R2(R=OH,CH3)4种异构体的结构和稳定性,表明1,9-C70(OH)2比7,8-C70(OH)2稳定,两者能量差为38.5kJ/mol,而7,8-C70(CH3)2比1,9-C70(CH3)2能量低23.0kJ/mol.以优化构型为基础,对C70R2(R=OH,CH3)的电子光谱进行了理论预测.  相似文献   

19.
应用低热固相合成法制备锂离子电池正极材料L iCo1/3N i1/3Mn1/3O2.研究该材料的结构与形貌,并比较它在商品L iPF6盐和在实验室合成的L iBOB(L iB(C2O4)2)盐电解液中的电化学性能.在L iPF6/EC+DMC+DEC电解液中,该材料表现出优良的电化学性能,其于0.5C、1C、1.5C、2C、3C放电倍率的初始比容量依次为167、163、163、157、147mAh/g,电池的循环性能也较好,说明低热固相合成的材料的有较好的高倍率性能.在L iBOB/EC+DEC+DE电解液中,0.5C倍率下比容量为160 mAh/g,较之L iPF6盐电解液的相差不大,但在高倍率下的比容量有所下降.  相似文献   

20.
本文主要用气相色谱逸出气体分析方法,借助于红外、紫外可见漫反射谱等手段研究了[Co(NH_3)_5(H_2O)]Br_3、[Cr(NH_3)_5(H_2O)](NO_3)_3与无机盐KY(Y=Cl,Br,Ⅰ)的固相反应,计算了失水与失氨的动力学参数,发现第一步反应失水生成一取代中间产物,其活化能与外加阴离子无关,为S_N1过程。第二步失氨反应活化能与中心离子M以及取代基Y有关,当M=Co(Ⅲ)时,反应体系的失氨活化能大小有下列顺序:Cl>Br>Ⅰ(E值分别为187、155、98kJ·mol~(-1)),M=Cr(Ⅲ)时则正好相反:Ⅰ>Br>Cl(E值分别为213、146、79 kJ·mol~(-1))。  相似文献   

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