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Polycrystalline ZSM-5 Aggregates Induced by Seed and Catalytic Performance in Methanol to Hydrocarbon
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作者 WANG Xuchang JIAO Chuyu +5 位作者 JI Zhuo JIAO Qirui QIN Bo DU Yanze ZHENG Jiajun LI Ruifeng 《无机材料学报》 SCIE EI CAS CSCD 北大核心 2024年第8期945-954,I0010-I0013,共14页
Synthesis of ZSM-5 zeolite typically utilizes small molecule polyamines or quaternary ammonium salts as organic structure guiding agent(OSDA).By contrast,the OSDA-free hydrothermal synthesis system eliminates the use ... Synthesis of ZSM-5 zeolite typically utilizes small molecule polyamines or quaternary ammonium salts as organic structure guiding agent(OSDA).By contrast,the OSDA-free hydrothermal synthesis system eliminates the use of organic templates and the subsequent calcination procedure.This not only reduces the cost of synthesis,but also prevents environmental pollution from the combustion of organic templates,representing an eco-friendly approach.Despite this,literature suggests that even so-called template-free synthesis systems often involve trace amount of organic substances like alcohol.In the present work,a calcined commercial ZSM-5 zeolite was served as seed,with sodium aluminate as aluminum source and silica sol as silicon source,ensuring an entirely template-free synthesis system.Polycrystalline ZSM-5 aggregates consisted of rod-like nanocrystals were successfully prepared in the completely OSDA-free system.Effects of the Si/Al ratio in ZSM-5 seed,dosage and crystallization conditions such as crystallization temperature and crystallization time on ZSM-5 synthesis were investigated.The results show that a highly crystallinity ZSM-5 aggregate consisting of primary nano-sized crystals less than 100 nm is produced from a gel precursor with 5.6%(in mass)seed after hydrothermal treatment for 48 h.Furthermore,the Si/Al ratio in ZSM-5 seed has little effect on the topological structure and pore structure of the synthesized samples.However,the seeds with a low Si/Al ratio facilitate faster crystallization of zeolite and enhance the acidity,especially the strong acid centers,of the catalyst.The catalytic performance of the synthesized polycrystalline ZSM-5 was evaluated during dehydration of methanol and compared with a commercial reference ZSM-5r.The results exhibit that as compared with the reference catalyst,the fabricated sample has a longer catalytic lifetime(16 h vs 8 h)attributed to its hierarchical pores derived from the loosely packed primary nanoparticles.Additionally,the prepared polycrystalline catalyst also exhibits a higher aromatics selectivity(28.1%-29.8%vs 26.5%). 展开更多
关键词 ZSM-5 polycrystalline aggregate crystal seed structure guiding agent
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Synthesis,Structural Characterization and Properties of Bis(1,5-diamino-1Htetrazolium)3,3'-bis(nitramino)-4,4'-azofurazan 被引量:3
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作者 许诚 毕福强 +3 位作者 张敏 刘庆 丁可伟 葛忠学 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2015年第9期1341-1346,共6页
An energetic salt of bis(l,5-diamino-lH-tetrazolium)3,3"-bis(nitramino)-4, 4x-azo- furazan (C6H10N2206) was synthesized with the total yield of 61.7% by using 3,4-diaminofurazan (DAF) as the starting material... An energetic salt of bis(l,5-diamino-lH-tetrazolium)3,3"-bis(nitramino)-4, 4x-azo- furazan (C6H10N2206) was synthesized with the total yield of 61.7% by using 3,4-diaminofurazan (DAF) as the starting material. The structure of the title compound was confirmed by NMR, IR, elemental analysis and single-crystal X-ray diffraction. It crystallizes in orthorhombic, space group P21/c with a = 10.739(2), b = 6.4765(12), c = 14.138(3) A, fl= 108.787(3)°, V= 930.9(3) A3, Z = 1, Mr= 486.36, Dc = 1.735 g.cm3, μ= 0.15 mm-1, F(000) = 496, R = 0.042 and wR = 0.121. The thermal stability was analyzed by subsequently differential scanning calorimetry (DSC). And the enthalpy of formation and detonation was calculated theoretically, showing the first decomposition temperature was 142.1℃, the enthalpy of formation was 1614.23 kJ.mol1 and the detonation velocity and detonation pressure were 8.781 km.s-1 and 30.7 GPa, respectively. 展开更多
关键词 bis(1 5-diamino-1H-tetrazolium)3 3?-bis(nitramino)-4 4?-azofurazan SYNTHESIS crystal structure furazan derivate
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Synthesis,structural characterization and solubility of 2-(1-substituted-1,11-undecylidene)-5-arylimino-△~3 -1,3,4-thiadiazolines
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作者 Shu Hui Jin Xiao Mei Liang Xu Yang Fu Heng Chen Dao Quan Wang 《Chinese Chemical Letters》 SCIE CAS CSCD 2009年第11期1267-1270,共4页
A series of novel 2-(1-substituted-1,11-undecylidene)-5-arylimino-△^3-1,3,4-thiadiazolines (4) were synthesized and their structure was characterized by ^1H NMR, ^13C NMR and elemental analysis. Their solubility ... A series of novel 2-(1-substituted-1,11-undecylidene)-5-arylimino-△^3-1,3,4-thiadiazolines (4) were synthesized and their structure was characterized by ^1H NMR, ^13C NMR and elemental analysis. Their solubility in both polar and non-polar solvents is significantly improved owing to the introduction of ethyl or methylthio group at cyclododecyl ring as compared with parent compounds [1, 2-(1,11-undecylidene)-5-arylimino-△^3-1,3,4-thiadiazolines]. However, their fungicidal activity against Rhizoctonia solani is less than that of parent compounds. X-ray diffraction analysis of a representative compound (4d) showed that the conformation of 12-membered ring is still [3333], in which the ethyl group present at the side-exo position and the thiadiazoline ring at the comer carbon. The thiadiazoline plane is perpendicular to the cyclododecyl one. 展开更多
关键词 2-(1-Substituted-1 11-undecylidene)-5-arylimino-△^3-1 3 4-thiadiazoline SOLUBILITY Crystal structure SYNTHESIS
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Structural and Magnetic Properties of MnO-P_2O_5-PbO Glasses
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作者 I.Ardelean M.Peteanu +2 位作者 O.Cozar V.Simon V.Mih and G.Botezan (Faculty of Physics, Babes-Bolyai University, 3400 Cluj-Napoca, Romania To whom correspondence should be addressedE-mail: arde@phys.ubbcluj.ro ) 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 1999年第5期453-456,共4页
The xMnO(100-x)[2P2O5.PbO] glasses were prepared with MnO concentration being in the range of 0≤x≤50 mole fraction and were investigated by EPR spectroscopy and magneticsusceptibility measurements. Octahedral symmet... The xMnO(100-x)[2P2O5.PbO] glasses were prepared with MnO concentration being in the range of 0≤x≤50 mole fraction and were investigated by EPR spectroscopy and magneticsusceptibility measurements. Octahedral symmetric sites tetragonally distorted were detected for x≤5 mole fraction MnO. Only Mn2+ ions were identified in these glasses, involved in dipoledipole interactions 展开更多
关键词 PBO Mno structural and Magnetic Properties of Mno-P2O5-PbO Glasses
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Ti^(4+)取代Zn^(2+)、Nb^(5+)对Bi_2O_3-ZnO-Nb_2O_5系介质材料结构和性能的影响 被引量:7
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作者 刘艳平 姚熹 张良莹 《功能材料》 EI CAS CSCD 北大核心 2002年第6期631-632,共2页
研究了Ti4+ 取代Zn2 + 、Nb5+ 对Bi2 O3 ZnO Nb2 O5系介质材料结构和性能的影响。研究表明 ,少量替代对于材料的结构和性能没有太大的影响 ;随着替代量的增加 ,相结构中出现正交Bi4Ti3 O12 相 ;微观形貌中出现棒晶 ;介电常数逐渐增大 ... 研究了Ti4+ 取代Zn2 + 、Nb5+ 对Bi2 O3 ZnO Nb2 O5系介质材料结构和性能的影响。研究表明 ,少量替代对于材料的结构和性能没有太大的影响 ;随着替代量的增加 ,相结构中出现正交Bi4Ti3 O12 相 ;微观形貌中出现棒晶 ;介电常数逐渐增大 ,温度系数逐渐向负温度系数方向移动。适量Ti4+ 替代可以获得性能很好的NP0介质材料。 展开更多
关键词 介质材料 结构 性能 电容器 Bi2O3-Zno-Nb2O5
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一维链状配位聚合物[Cd{5-(NO_2)sal}_2(2,2′-bipy)]_n的合成与晶体结构(英文)
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作者 温德才 谢静 +1 位作者 钟春龙 拓宏桂 《无机化学学报》 SCIE CAS CSCD 北大核心 2008年第10期1718-1720,共3页
A coordination polymer of [Cd{5-(NO2) sal}2(2,2'-bipy)]n(5-(NO2) sal=5-nitrosalicylate,2,2'-bipy=2,2'-bipyridine) was synthesized by hydrothermal reaction and characterized by elemental analysis,IR and X-r... A coordination polymer of [Cd{5-(NO2) sal}2(2,2'-bipy)]n(5-(NO2) sal=5-nitrosalicylate,2,2'-bipy=2,2'-bipyridine) was synthesized by hydrothermal reaction and characterized by elemental analysis,IR and X-ray diffraction single crystal structure analysis.The title complex crystallizes in monoclinic with space group C2/c,a=2.730 8(16) nm,b=1.272 3(5) nm,c=0.674 5(3) nm,β=96.73(2) °,V=2.327(2) nm3,Z=4,R=0.022 2,wR=0.057.The 5-nitrosalicylate anions doubly bridge the Cd(Ⅱ) atoms to form one-dimensional polymeric chain with the repeated eight-membered ring units(Cd-O-C-O) 2.The crystal structure is stabilized by intra-and interchain hydrogen bonds interactions.CCDC:694568. 展开更多
关键词 配位聚合物 5-硝基水杨酸 镉(Ⅱ) 晶体结构
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K_2Ln(NO_3)5·2H_2O(Ln=Pr,Nd)的晶体结构和非线性光学性质
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作者 董文庭 张洪杰 +2 位作者 苏锵 林永华 王淑梅 《人工晶体学报》 EI CAS CSCD 北大核心 1998年第3期219-224,共6页
本文采用水溶液中生长晶体的方法合成了KLnN(Ln=Pr,Nd)的单晶,研究了KPrN的单晶结构及KLnN(Ln=Pr,Nd)的非线性光学性质。KLnN(Ln=Pr,Nd)均属正交晶系,Fdd2空间群。KPrN的晶胞... 本文采用水溶液中生长晶体的方法合成了KLnN(Ln=Pr,Nd)的单晶,研究了KPrN的单晶结构及KLnN(Ln=Pr,Nd)的非线性光学性质。KLnN(Ln=Pr,Nd)均属正交晶系,Fdd2空间群。KPrN的晶胞参数为:a=2.1411(3)nm,b=1.12210(10)nm,c=1.2208(2)nm,Z=6,R=0.0240.KLnN(Ln=Pr,Nd)的二次谐波光强与KLnN(Ln=La,Ce)处于同样的数量级.KLnN容易生长出大尺寸晶体,是一类有应用前景的可产生蓝绿光的倍频转换材料。 展开更多
关键词 非线性光学晶体 晶体生长 晶体结构 硝酸镨钾
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Cu-ZSM-5分子筛中铜的精细结构和NO催化分解 被引量:7
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作者 方书农 伏义路 林培琰 《Chinese Journal of Catalysis》 SCIE CAS CSCD 北大核心 1995年第3期213-216,共4页
用EXAFS技术研究了不同交换度的和还原、再氧化处理的Cu-ZSM-5分子筛中铜离子的精细结构.在ZSM-5分子筛中,存在两种铜可占据的位置:一种具有饱和的氧配位和较短的铜氧距离,另一种钢氧配位不饱和且铜氧距离较远.... 用EXAFS技术研究了不同交换度的和还原、再氧化处理的Cu-ZSM-5分子筛中铜离子的精细结构.在ZSM-5分子筛中,存在两种铜可占据的位置:一种具有饱和的氧配位和较短的铜氧距离,另一种钢氧配位不饱和且铜氧距离较远.离子交换时,铜离子可能优先占据前者,其量低于30%.这两类铜的催化能力差别甚大,前者几乎无催化分解NO的活性. 展开更多
关键词 铜离子 精细结构 一氧化氮 催化分解 分子筛
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含能配合物[Ag_2(DAT)_4](NO_3)_2(DAT=1,5-二氨基四唑)的合成、晶体结构及性能 被引量:1
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作者 张至斌 许彩霞 +2 位作者 张建国 殷昕 尹磊 《含能材料》 EI CAS CSCD 北大核心 2016年第8期757-762,共6页
以1,5-二氨基四唑(DAT)与硝酸银为起始原料制备了新型含能配合物[Ag_2(DAT)_4](NO_3)_2,收率86%。用元素分析和傅里叶变换红外光谱法对其结构进行了表征。培养了目标配合物的单晶。用X-射线单晶衍射仪测定了其晶体结构。用差示扫描量热... 以1,5-二氨基四唑(DAT)与硝酸银为起始原料制备了新型含能配合物[Ag_2(DAT)_4](NO_3)_2,收率86%。用元素分析和傅里叶变换红外光谱法对其结构进行了表征。培养了目标配合物的单晶。用X-射线单晶衍射仪测定了其晶体结构。用差示扫描量热法研究了其热分解行为。用Kissinger法和Ozawa法计算了其非等温反应动力学参数:活化能E_K和E_O。计算了其热爆炸临界温度T_b。用氧弹测定了其燃烧热Q_v。计算了其标准生成焓Δ_fH~Θ_(298))。测试了目标配合物的摩擦、撞击和火焰感度。结果表明,目标配合物属于单斜晶系,P21/n空间群,晶胞参数为:a=6.8109(9),b=19.654(3),c=8.4510(11),β=102.590(3)°,V=1104.1(3)~3,Z=2,Dc=2.228 g·cm^(-3),F(000)=729。对目标配合物,E_K=204.9 k J·mol^(-1),E_O=202.8 k J·mol^(-1),T_b=224.4℃,Q_v=-4177.59k J·mol^(-1),Δ_fH~Θ_(298)=258.14 k J·mol^(-1),目标配合物对撞击和火焰不敏感,对摩擦较为敏感。 展开更多
关键词 1 5-二氨基四唑(DAT) 含能配合物 晶体结构 热分析 感度
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MgTi_(2)O_(5)对钛酸铝陶瓷低温合成及性能的影响
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作者 张宏泉 程光健 +1 位作者 文进 陈鹏杰 《硅酸盐通报》 CAS 北大核心 2024年第12期4545-4552,共8页
以预合成MgTi_(2)O_(5)和MgO+2TiO_(2)原位合成MgTi_(2)O_(5)两种方式引入钛酸铝陶瓷制备所需添加剂,研究MgTi_(2)O_(5)对钛酸铝陶瓷物相组成和性能的影响。结果表明,MgTi_(2)O_(5)或MgO+2TiO_(2)均可通过形成固溶体促进钛酸铝的低温合... 以预合成MgTi_(2)O_(5)和MgO+2TiO_(2)原位合成MgTi_(2)O_(5)两种方式引入钛酸铝陶瓷制备所需添加剂,研究MgTi_(2)O_(5)对钛酸铝陶瓷物相组成和性能的影响。结果表明,MgTi_(2)O_(5)或MgO+2TiO_(2)均可通过形成固溶体促进钛酸铝的低温合成,但添加少量MgTi_(2)O_(5)即可在较低温度下有效促进钛酸铝晶体的合成。当MgO含量为2%(摩尔分数)时,在1300℃下添加MgTi_(2)O_(5)的钛酸铝合成率比添加MgO+2TiO_(2)的提高了28.4个百分点;在钛酸铝合成率相近的前提下,添加MgTi_(2)O_(5)比添加MgO+2TiO_(2)的烧成温度低。当添加6%MgTi_(2)O_(5)时,在1280~1350℃所烧成陶瓷样品的热膨胀系数介于-0.11×10^(-6)~0.58×10^(-6)℃^(-1)。随着烧成温度升高,由于晶体的各向异性及过度生长,晶体内部存在的微裂纹易使所得钛酸铝陶瓷的抗折强度降低。 展开更多
关键词 MgTi_(2)O_(5) 钛酸铝 低温合成 烧成温度 低热膨胀 晶体结构
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Synthesis,Spectroscopic Properties and Crystal Structural Characterization of a Triphenyltin(IV) Complex with 5-Bromonicotinic Acid 被引量:5
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作者 GAO Zhong-Jun YIN Han-Dong LI Gang XU Hao-Long 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 北大核心 2006年第10期1228-1232,共5页
A novel organotin complex [Ph3Sn(C2H5OH)(OCOC5H3NBr)SnPh3(OCOC5H3NBr)] has been synthesized by the reaction of 5-bromonicotinic acid with triphenyltin hydroxide in ethanol and characterized by elemental analysis... A novel organotin complex [Ph3Sn(C2H5OH)(OCOC5H3NBr)SnPh3(OCOC5H3NBr)] has been synthesized by the reaction of 5-bromonicotinic acid with triphenyltin hydroxide in ethanol and characterized by elemental analysis, IR and ^1H NMR. The crystal structure was determined by X-ray single-crystal diffraction. The crystal belongs to the monoclinic system, space group P21/c with a = 15.564(2), b = 24.975(4), c = 12.2973(19)°A, β = 92.224(2)°, Z = 4, V = 4776.5(13)°A^3, Dc = 1.596 g/cm^3, μ(MoKα) = 2.765 mm^-1, F(000) = 2264, R = 0.0385 and wR = 0.0667. In the molecular structure of the title complex, the tin atoms are five-coordinated in a trigonal bipyramidal geometry. 展开更多
关键词 ORGAnoTIN 5-bromonicotinic acid SYNTHESIS crystal structure
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Two Novel Nitrogen-rich Energetic Coordination Compounds M_2(DAT)_5(H_2O)_3(TNR)_2(M = Zn and Co):Synthesis,Characterization,Thermal Properties and Sensitivity 被引量:5
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作者 梁彦会 张建国 +3 位作者 崔燕 张同来 周遵宁 杨利 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2012年第3期327-338,共12页
Two novel energetic coordination compounds Zn2(DAT)5(H2O)3(TNR)2 and Co2(DAT)5(H2O)3(TNR)2 were synthesized and their structures were characterized by elemental analysis and FT-IR spectroscopy.The crystal ... Two novel energetic coordination compounds Zn2(DAT)5(H2O)3(TNR)2 and Co2(DAT)5(H2O)3(TNR)2 were synthesized and their structures were characterized by elemental analysis and FT-IR spectroscopy.The crystal structures were determined by single-crystal X-ray diffraction.The results reveal that the compounds have similar molecular structures and the crystals belong to the triclinic system,space group P with a = 11.491(3),b = 13.564(3),c = 15.496(3) ,V = 2180.4(8) 3,C17H28 Zn2N36O19,Mr = 1203.02 g·mol-1,Dc = 1.832 g·cm-3,μ(MoKα) = 1.221 mm-1,F(000) = 1223,Z = 2,R = 0.0596 and wR = 0.1514 for 11289 observed reflections(I 〉 2σ(I)) for Zn2(DAT)5(H2O)3(TNR)2 and a = 11.5291(13),b = 13.4894(15),c = 15.4852(17) ,V = 2164.8(4) 3,C17H28Co2N36O19,Mr = 1190.14 g·mol-1,Dc = 1.826 g·cm-3,μ(MoKα) = 0.888 mm-1,F(000) = 1211,Z = 2,R = 0.0576 and wR = 0.1431 for 11218 observed reflections(I 〉 2σ(I)) for Co2(DAT)5(H2O)3(TNR)2,respectively.The thermal decomposition characteristics of the com-pounds were investigated using differential scanning calorimetry and thermal gravimetry-diffediffer-rential thermal gravimetry.The results of thermal decomposition processes were similar for the two compounds.Both undergo four-step decomposition after the loss of coordinated H2O molecules.The final solid residues for the two DAT complexes were the corresponding metal oxides.The kinetic parameter of the first exothermic process of the compounds was studied by applying the Kissinger and Ozawa-Doyle methods.The thermodynamic parameters of the activation could be calculated.Sensitivity tests revealed that Co2(DAT)5(H2O)3(TNR)2 was more sensitive than Zn2(DAT)5(H2O)3(TNR)2. 展开更多
关键词 1 5-diaminotetrazole energetic coordination compound crystal structure thermal decomposition sensitivity properties
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基于5-氨基烟酸的锰金属有机框架的合成、结构及荧光传感性质
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作者 江涛 梁晓彤 +4 位作者 廖思燕 刘小慧 余嘉俊 邹霖 邱燕璇 《人工晶体学报》 CAS 北大核心 2024年第2期307-314,321,共9页
室温下,通过溶液法将5-氨基烟酸(5-Hana)与MnCl_(2)反应,成功合成了一例新的三维Mn(II)金属有机框架[Mn_(2)(5-ana)_(4)(H_(2)O)]n(命名为Mn-MOF)。通过X射线单晶衍射、X射线粉末衍射、元素分析、红外光谱、热重分析、紫外-可见光谱和... 室温下,通过溶液法将5-氨基烟酸(5-Hana)与MnCl_(2)反应,成功合成了一例新的三维Mn(II)金属有机框架[Mn_(2)(5-ana)_(4)(H_(2)O)]n(命名为Mn-MOF)。通过X射线单晶衍射、X射线粉末衍射、元素分析、红外光谱、热重分析、紫外-可见光谱和荧光光谱法对配合物的结构和性质进行表征。结构分析表明,配合物属单斜晶系,具有双节点(2,8)-c配位网络结构,其中[Mn_(2)(CO_(2))_(2)(H_(2)O)]二聚单元作为8-连接节点,5-ana-配体作为2-连接节点。分子范德瓦耳斯表面静电势(ESP)分析表明,5-ana-配体的第一反应位点在羧基氧原子附近,ESP最小值为-143.37 kcal·mol^(-1),第二和第三反应位点分别位于吡啶环和氨基氮原子附近。Mn-MOF常温下具有良好的热稳定性。荧光光谱测试显示配合物在256 nm光激发下的最大发射波长为402 nm。更重要的是,Mn-MOF可以通过荧光猝灭实现对Fe^(3+)的选择性识别,且猝灭效率达到98.71%,可作为潜在的荧光探针分析水溶液中的Fe^(3+)。 展开更多
关键词 5-氨基烟酸 Mn(Ⅱ) 晶体结构 金属有机框架 荧光传感器 铁离子
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Synthesis and Crystal Structure of a Novel Heterometallic Complex with 1,2,4,5-Benzenetetracarboxylic Acid and 1,3,5-Tris(imidazol-1-ylmethyl)-2,4,6-trimethylbenzene 被引量:2
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作者 刘光祥 徐衡 任小明 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2010年第12期1792-1797,共6页
A novel heterometallic complex,[Zn4Ni(OH)2(btec)2(titb)2(H2O)2]·2H2O(1)(H4btec=1,2,4,5-benzenetetracarboxylic acid,titb=1,3,5-tris(imidazol-1-ylmethyl)-2,4,6-trime-thylbenzene),has been hydrothermal... A novel heterometallic complex,[Zn4Ni(OH)2(btec)2(titb)2(H2O)2]·2H2O(1)(H4btec=1,2,4,5-benzenetetracarboxylic acid,titb=1,3,5-tris(imidazol-1-ylmethyl)-2,4,6-trime-thylbenzene),has been hydrothermally prepared and characterized by IR spectroscopy,elemental analysis and single-crystal X-ray diffraction.The crystal is of triclinic system,space group P1 with a=10.817(10),b=11.878(11),c=14.569(14),α=71.762(12),β=76.122(13),γ=71.493(13)°,V=1665(3)3,C62H62N12O22Zn4Ni,Mr=1647.43,Dc=1.643 g/cm3,F(000)=842,μ=1.784 mm-1 and Z=1.The final R=0.0531 and wR=0.0890 for 3545 observed reflections(Ⅰ 2σ(Ⅰ)).In the title complex,the btec ligand acts as a five-dentate bridging ligand to link up zinc and nickel atoms into a lamellar framework,which are further interlinked into a 3-D framework via the titb ligands. 展开更多
关键词 heterometallic complex crystal structure 1 2 4 5-benzenetetracarboxylate imidazole
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Correlation between H-ZSM-5 crystal size and catalytic performance in the methanol-to-aromatics reaction 被引量:15
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作者 Lingzhi Yang Zhiyuan Liu +3 位作者 Zhi Liu Wenyong Peng Yunqi Liu Chenguang Liu 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 北大核心 2017年第4期683-690,共8页
The porosity of H‐ZSM‐5zeolite is known to facilitate the diffusion of molecules in the methanol‐to‐aromatics(MTA)reaction.The activity and selectivity of the H‐ZSM‐5catalyst in the MTAreaction has been studied ... The porosity of H‐ZSM‐5zeolite is known to facilitate the diffusion of molecules in the methanol‐to‐aromatics(MTA)reaction.The activity and selectivity of the H‐ZSM‐5catalyst in the MTAreaction has been studied as a function of crystal size.ZSM‐5zeolites with different crystal sizeswere successfully synthesized by conventional hydrothermal methods.Tailoring ZSM‐5particle sizewas easily controlled by changes to the sol‐gel composition,and in particular,the deionized waterto tetrapropylammonium hydroxide ratio,and crystallization time.The structure of the H‐ZSM‐5zeolites were characterized by X‐ray diffraction and the morphology of the zeolite particles wasdetermined by scanning electron microscopy.N2adsorption‐desorption measurements establishedchanges to the textural properties,and compositional properties were characterized by X‐ray fluorescencespectroscopy.Acidity measurements of the catalysts were measured by pyridine‐adsorbedFourier transform infrared spectroscopy and the temperature‐programmed desorption of ammonia.After subjecting the catalysts to the MTA reaction,the total amount of coke formed on the spentdeactivated catalysts was determined by thermal gravimetric analysis.The results show that theSiO2/Al2O3molar ratios and acidic properties of the H‐ZSM‐5samples are similar,however,thenano‐sized hierarchical ZSM‐5zeolite with an additional level of auxiliary pores possesses a higher 展开更多
关键词 METHAnoL AROMATICS Nano‐sized H‐ZSM‐5 Hierarchical structure Crystal size
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Synthesis and anti-HBV activity of novel 5-substituted pyridin-2(1H)-one derivatives 被引量:2
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作者 Zhang, Yi Kai Lv, Zhi Liang +1 位作者 Niu, Chun Juan Li, Ke 《Chinese Chemical Letters》 SCIE CAS CSCD 2010年第3期290-292,共3页
Four novel 5-substituted pyridine-2(1H)-one derivatives were designed and synthesized by using addition-elimination reactions.The structures of these novelly synthesized compounds were verified by ~1H NMR,ESI-MS and s... Four novel 5-substituted pyridine-2(1H)-one derivatives were designed and synthesized by using addition-elimination reactions.The structures of these novelly synthesized compounds were verified by ~1H NMR,ESI-MS and single crystal X-ray diffraction.Furthermore,all four compounds(most notably compound 7a) were found to be highly efficient against hepatitis B virus (HBV) in cultured HepG2 2.2.15 cell,making them promising drug candidates for potential bioactive molecule against hepatitis B. 展开更多
关键词 5-Substituted pyridin-2(1H)-one SYNTHESIS Crystal structure Anti-HBV activity
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A Novel Two-dimensional Lead(Ⅱ) Coordination Polymer Based on Dinuclear Lead(Ⅱ) Unit Containing(5-Chloro-quinolin-8-yloxy) Acetate 被引量:3
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作者 李静 王玉红 宋瑞峰 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2014年第10期1488-1494,共7页
A novel two-dimensional lead(II) coordination polymer 1, [C11H7Cl2NO3Pb]n, has been prepared by solvothermal reaction of new bridging ligand(5-chloro-quinolin-8-yloxy)acetic acid(HL) with PbCl2, and its structur... A novel two-dimensional lead(II) coordination polymer 1, [C11H7Cl2NO3Pb]n, has been prepared by solvothermal reaction of new bridging ligand(5-chloro-quinolin-8-yloxy)acetic acid(HL) with PbCl2, and its structure was characterized by IR, elemental analysis, TG-DTA and single-crystal X-ray diffraction analysis. The crystal is of monoclinic system, space group P21/c with a = 16.7603(7), b = 8.6907(4), c = 8.4745(3)A, β = 101.1110(11)°, C11H7Cl2NO3 Pb, Mr = 479.27, V = 1211.25(9)A3, Z = 4, Dc = 2.628 g/cm^3, F(000) = 880, μ = 14.367 mm^-1, R = 0.0173 and wR = 0.0508. The asymmetric unit contains one lead(II) cation, one(5-chloro-quinolin-8-yloxy)acetate(L) ligand and a chloride ion. The PbII center is hepta-coordinated in a distorted pentagonal bipyramidal geometry. The coordination sphere of the Pb atom is completed by two oxygen atoms and one nitrogen atom of the same L ligand, two bridging chloride ions and two bridging oxygen atoms of two adjacent L ligands. Two PbII centers are linked by the two L ligands to form a C2-symmetric dimer unit with a planar [Pb2O2] ring. Each dimer unit acts as a secondary building unit(SBU) and links adjacent four dimer units by the chloride atoms and oxygen atoms of carboxylate groups of L, forming a two-dimensional array. Such two-dimensional layers are packed through intermolecular C–H…Cl hydrogen bonds into a three-dimensional supramolecular structure. When the dimer unit is viewed as a 4-connected node, 1 is simplified as a 4-nodal 2-D network with square lattices of the diagonal lengths to be 6.079(1)A. The fluorescence emission peak of complex 1 appears near 407 nm. 展开更多
关键词 lead(II) complex crystal structure 5-chloro-quinolin-8-yloxy) acetic acid coordination polymer
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Synthesis and Crystal Structure of a Novel Ternary Borate, NaSrB_5O_9 被引量:3
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作者 陈学安 左建龙 +2 位作者 常新安 臧和贵 肖卫强 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 北大核心 2007年第9期1081-1086,共6页
A novel ternary borate, sodium strontium pentaborate, NaSrB5O9, has been prepared by solid-state reaction below 800 ℃. The single-crystal X-ray structural analysis showed that NaSrB5O9 crystallizes in monoclinic, spa... A novel ternary borate, sodium strontium pentaborate, NaSrB5O9, has been prepared by solid-state reaction below 800 ℃. The single-crystal X-ray structural analysis showed that NaSrB5O9 crystallizes in monoclinic, space group P21/c with a = 6.499(2), b = 13.979(3), c = 8.045(2)A, β = 106.92(2)°, V = 699.2(3)A^3, Z = 4, Mr = 308.66, Dc = 2.932 g/cm^3, μ = 7.804 mm^-1, F(000) = 584, R = 0.0264 and wR = 0.0621 for 2426 observed reflections and 146 variables. NaSrB5O9 is a layered compound containing double ring B5O11 building units composed of two BO4 tetrahedra and three BO3 triangles. Each B5O11 unit is connected to four other equivalent units through exocyclic oxygen atoms to form a two-dimensional ∞^2 [B5O9]^3- layer. Symmetry-center related layers are stacked along the b axis and held together by Na^+ and Sr^2+ cations via electrostatic interactions. 展开更多
关键词 NaSrB5O9 BORATE SYNTHESIS crystal structure
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Solvothermal Synthesis and Structure of the [Co(5-NH_2-bdc)(4,4'-dpdo)(H_2O)]_n Complex (4,4'-dpdo = 4,4'-Bipyridrl-N,N'-dioxide,5-NH_2-bdc = 5-Aminoisophthalic Acid) 被引量:1
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作者 张淑华 靳振江 +2 位作者 邹华红 钟凡 葛成敏 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2009年第12期1630-1634,共5页
The title compound [Co(5-NH2-bdc)(4,4'-dpdo)(H2O)]n 1 (5-NH2-bdc = 5-aminoiso- phthalic acid,4,4'-dpdo = 4,4'-bipyridrl-N,N'-dioxide) crystallizes in triclinic,space group P1 with a = 4.999(1),b = 10.072... The title compound [Co(5-NH2-bdc)(4,4'-dpdo)(H2O)]n 1 (5-NH2-bdc = 5-aminoiso- phthalic acid,4,4'-dpdo = 4,4'-bipyridrl-N,N'-dioxide) crystallizes in triclinic,space group P1 with a = 4.999(1),b = 10.072(2),c = 13.028(3) A,α = 107.72(3),β = 92.58(3),γ = 98.11(3)°,V = 615.9(3) A^3,F(000) = 356,Rint = 0.0186,Z = 2,R = 0.0333,wR = 0.0721,S = 1.032 and (Δ/σ)max = 0.001. In the molecule of 1,the Co(II) cation is coordinated by three O-atoms of two 5-NH2-bdc ligands,one N-atom of another 5-NH2-bdc ligand,one O-atom of 4,4'-dpdo and one terminal O-atom of water molecule. The molecules construct a 2-D network through bridging 5-NH2-bdc and 4,4'-dpdo ligands,and further form a 3-D network through N–H and O–H hydrogen bonds. The network topology of 1 can be simplified as a rare 2D (3,6)-connected (426381) net. 展开更多
关键词 cobalt crystal structure 4 4'-dpdo 5-aminoisophthalic acid
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The Novel Benzo-15-Crown-5 with Palladium(II) Complex: [Na(B15CS)]_2,[Pd(SCN)_4] 被引量:1
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作者 Lan Ying ZHU Jian Min DOU +3 位作者 Ying LIU De Zhi SUN Pei Ju ZHENG Chen Xia DU Yu ZHU Department of Biology and Chemistry, Liaocheng Teacher’s University, Liaocheng 252000 Research Center of Analysis and Measurement, Fudan University, Shanghai 200433 Key 《Chinese Chemical Letters》 SCIE CAS CSCD 2000年第9期835-838,共4页
A novel Pd(II) Benzo-15-crown-5 complex [Na(B15CS)]_2[Pd(SCN)_4] has been isolated and characterized by IR and X-ray diffraction analysis. The crystal structure belongs to monoclinic, space group P2_1,/n with cell dim... A novel Pd(II) Benzo-15-crown-5 complex [Na(B15CS)]_2[Pd(SCN)_4] has been isolated and characterized by IR and X-ray diffraction analysis. The crystal structure belongs to monoclinic, space group P2_1,/n with cell dimensions, a = l.0164(6), b = l.3743(3), c = l.4987(7) nm, β = 95.248(6) °, V = 2.0847 'nm_3, Z = 2, F(000) = 944, R = 0.053, Rw = 0.072. The compound consists of two [Na(B15CS)]+ complex canons and a [Pd(SCN)4_]^(2-) complex anion. Each sodium ion is coordinated by five crown ether oxygen atoms and one N atom from the SCN group of [Pd(SCN)_4]^(2-) to form stable neutral complex. 展开更多
关键词 Benzo-15-crown-5 crown ether crystal structure palladium complex.
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