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1.
合成了3个超分子化合物[M(4,4'-bipy)2(H2O)4]·(4,4'-bipy)2·(3,5-diaba)2·8H2O(M=Co(1),Ni(2),Cd(3);4,4'-bipy=4,4'-联吡啶;3,5-diaba=3,5-二氨基苯甲酸阴离子),用红外光谱、元素分析及X-射线单晶衍射进行了表征。3个化合物的晶体都属于单斜晶系,空间群为P2/c。晶体学参数:化合物1:a=0.9389(2)nm,b=0.7751(1)nm,c=3.9284(6)nm,β=90.14(2)°,V=2.85880(69)nm3,Z=4,Dc=1.397g·cm-3,F(000)=1266,μ=0.380mm-1,R1=0.0349,wR2=0.0829;化合物2:a=0.9383(2)nm,b=0.7753(1)nm,c=3.9218(6)nm,β=90.09(1)°,V=2.85280(68)nm3,Z=2,Dc=1.399g·cm-3,F(000)=1268,μ=0.420mm-1,R1=0.0366,wR2=0.0805;化合物3:a=0.94091(13)nm,b=0.77885(11)nm,c=3.9712(5)nm,β=90.10°,V=2.9102(7)nm3,Z=2,Dc=1.433g·cm-3,F(000)=1308,μ=0.454mm-1,R1=0.0468,wR2=0.0964。3,5-diaba未参与配位,在配位阳离子[M(4,4'-bipy)2(H2O)4]2 中,金属离子M髤与来自2个4,4'-bipy的2个氮原子和4个水分子的氧原子配位,呈八面体的几何构型。分子中还存在未配位的4,4'-bipy。通过配位阳离子、游离4,4'-bipy及未配位的3,5-diaba间的丰富氢键,构建成具有三维结构的超分子化合物。  相似文献   
2.
A one-dimensional double-chain coordination polymer [Mn(phen)(tsgluo)] was synthesized in a mixed solution and its crystal structure was determined by X-ray diffraction method. It crystallizes in orthorhombic system with space group P212121. The crystal data are: a=0.530 78(17) nm, b=1.723 9(5) nm, c=2.456 9(8) nm, Z=4, μ=0.729 mm-1, Dc=1.579 g·cm-3, V=2.248 1(12) nm3, R1=0.033 1, ωR2=0.078 9. In the title complex, each Mn(Ⅱ) ion presents a octahedral geometry with the coordination of two nitrogen atoms from 1,10-phenanthroline and four oxygen atoms from three different tsgluo2- ligands. The γ-carboxyl coordinates to Mn(Ⅱ) in the mode of bidentate chelate, while the α-carboxyl coordinates in a bidentate bridging mode. CCDC: 253910.  相似文献   
3.
Liang  Hong  Chen  Zhen-Feng  Hu  Rui-Xiang  Yu  Qing  Zhou  Zhong-Yuan  Zhou  Xiang-Ge 《Transition Metal Chemistry》2002,27(1):102-104
(n-Bu4N)4[Mo8O26] reacts with the Na salt of 2-mercaptopyridine N-oxide (NaPT) in MeCN to give the complex (n-Bu4N)2[MoO2(PT)2·Mo4O8(-O)2(3-O)2(PT)2] (1) which contains two metal centres: one being mononuclear molybdenum chelating to two PT ligands, and the other a tetranuclear oxomolybdenum cluster with two PT ligands at the terminal point. The i.r. spectrum of the title complex exhibits absorption bands at 911.5 and 881.9 cm–1, characteristic of the [cis-MoO2]2+ fragment.  相似文献   
4.
Two new ternary complexes [Zn(3-aba)2(phen)](2.58H2O 1 and {[Cd(3-aba)- (phen)2]·(NO3)·(1.5H2O)}n 2 (3-aba = 3-aminobenzoic acid anion, phen = 1,10-phenanthroline) were synthesized and characterized by elemental analysis, IR, UV spectrum and X-ray diffraction. Complex 1 crystallizes in the rhombohedral system, space group R with a = 3.5733(3), b = 3.5733(3), c = 1.1231(2) nm, V = 12.419(3) nm3, C26H25.17N4O6.58Zn, Mr = 564.37, Z = 18, F(000) = 5253, μ = 0.937 mm-1, Dc = 1.358 g/cm3, R = 0.0668 and wR = 0.1690 for 2424 observed reflections (I > 2σ(I)). Complex 2 belongs to the tetragonal system, space group P4/ncc with a = 2.88451(10), b = 2.88451(10), c = 1.55571(11) nm, V = 12.9441(11) nm3, C31H25CdN6O6.50, Mr = 697.97, Z = 16, F(000) = 5648, μ = 0.727 mm-1, Dc = 1.433 g/cm3, R = 0.0607 and wR = 0.1742 for 3468 observed reflections (I > 2σ(I)). Complex 1 displays a mononuclear structure. The carboxylate group of 3-aminobenzoic acid anion coordinates to Zn(Ⅱ) in a chelating bidentate mode, and the nitrogen atom of the ligand does not involve in coordination. Complex 2 exhibits a one-dimensional chain structure with 3-aminobenzoic acid anion coordinating to Cd(Ⅱ) in a μ2-bridging mode through its nitrogen atom and one of its oxygen atoms.  相似文献   
5.
Ru/ZrO2·xH2O催化喹啉加氢反应   总被引:1,自引:0,他引:1  
制备了负载型催化剂Ru/ZrO2·xH2O,并用XRD、XPS和TEM对催化剂进行了表征,所制得的催化剂金属钌的平均粒径约为3.8 nm.在2MPa和40℃的温和条件下,以水为溶剂时,Ru/ZrO2·rH2O催化喹啉加氢生成1,2,3,4-四氢喹啉的选择性达98.0%,而且表现出较强的抗氮中毒能力,催化剂循环使用性能稳定.对喹啉加氢反应中的催化反应机理进行了探讨.  相似文献   
6.
用X射线衍射方法对液相烧结的RCo5型永磁体内的金属相结构进行了分析,配合着也观测了磁性,烧结体无例外地有一个约0.3毫米厚的表皮层;故须把烧结体的表皮层和核心部分分离,对它们分别进行观测,磁性测量则只是对核心部分作的,结果表明,表皮层与核心相比,它的结构较为复杂;但仅就成分讲,则它的R含量较高,Co含量较低,具有最大矫顽力的烧结体核心只显示了一个金属相,即具有CaZn5型结构的RCo5型金属间化合物,X射线衍射未察觉有其它金属相(R2Co7或R2Co17)的存在;这情况出现在63%(重量)的总Co含量附近,也对烧结前的混合粉中的“液相”含量作了变化,使烧结体的总Co含量偏离此值,这些不同Co含量的烧结体核心中一般地有第二个金属相的出现,随着这第二相(不论是R2Co7或R2Co17)的出现,核心的永磁特性就降低,根据上述结果,试提出以液相转变为主的烧结模型,磁性最佳的烧结体核心本质上是单相的RCo5型结构,这一结果是与Strnat等提出的以R2Co7外延层的存在为基础的“磁壳钉扎模型”相矛盾的。  相似文献   
7.
高岩  陈瑞云  吴瑞祥  张国锋  肖连团  贾锁堂 《物理学报》2013,62(23):233601-233601
本文通过外加电场改变氧化石墨烯团簇分子的共振能量,利用激光激发氧化石墨烯产生的共振荧光特性测量氧化石墨烯在电场作用下的极化动力学特性. 发现存在外加电场使得荧光共振峰的半高全宽趋于饱和的时间特性,而不同的氧化石墨烯团簇分子的荧光共振峰的暂态特性同时反映了电场对氧化石墨烯产生定向极化和变形极化的动力学特性. 关键词: 氧化石墨烯 团簇分子 电场 极化动力学  相似文献   
8.
Rhodium catalyzed hydroformylation of a-methylstyrene was investigated in the presence of monodentate phosphine ligands L1–L6. We found that the phosphine with good p-acceptability could efficiently improve the activity of the a-methylstyrene hydroformylation. The big steric hindrance of a-C in a-methylstyrene enhanced the regioselectivity towards the linear aldehyde, which resulted in3-phenylbutanal as the predominant product(99.0%). When tris(N-pyrrolyl)phosphine(L1) modified Rh(acac)(CO)_2was employed as the catalyst, the TOF could reach up to 5786 h~(-1)in the a-methylstyrene hydroformylation at relatively mild conditions(110 8C, 6 MPa).  相似文献   
9.
This paper describes the pFind 2.0 software package for peptide and protein identification via tandem mass spectrometry. Firstly, the most important feature of pFind 2.0 is that it offers a modularized and customized platform for third parties to test and compare their algorithms. The developers can create their own modules following the open application programming interface (API) standards and then add it into workflows in place of the default modules. In addition, to accommodate different requirements, the package provides four automated workflows adopting different algorithm modules, executing processes and result reports. Based on this design, pFind 2.0 provides an automated target-decoy database search strategy: The user can just specify a certain false positive rate (FPR) and start searching. Then the system will return the protein identification results automatically filtered by such an estimated FPR. Secondly, pFind 2.0 is also of high accuracy and high speed. Many pragmatic preprocessing, peptide-scoring, validation, and protein inference algorithms have been incorporated. To speed up the searching process, a toolbox for indexing protein databases is developed for high-throughput applications and all modules are implemented under a new architecture designed for large-scale parallel and distributed searching. An experiment on a public dataset shows that pFind 2.0 can identify more peptides than SEQUEST and Mascot at the 1% FPR. It is also demonstrated that this version of pFind 2.0 has better usability and higher speed than its previous versions. The software and more detailed supplementary information can both be accessed at http://pfind.ict.ac.cn/.  相似文献   
10.
Schiff碱N-氧化吡啶-2-甲醛缩氨基硫脲的晶体结构   总被引:4,自引:0,他引:4  
刘斌  胡瑞祥  梁宏  郁开北 《结构化学》1999,18(6):414-417
合成了标题Schiff碱并获得了其单晶,化学式为C7H8N4OS,Mr= 196.23,经X射线单晶衍射分析,该晶体属于单斜晶系,空间群为C2/c,晶胞参数: a= 13.198(2),b= 8.070(1),c= 16.999(2),β= 102.760(10)°,V= 1765.8(4)3,Z= 8,Dc=1.476g/cm 3,μ= 0.330m m - 1,F(000)= 816,在2.46°< θ< 29.00°范围内以ω扫描方式收得独立衍射点2347 个,其中I> 2σ(I)的可观测点为1687 个。最终偏离因子R=0.0344,w R= 0.0843,(Δ/σ)m ax= 0.001,S= 1.082。分子为平面构型。与相应配合物的晶体结构进行了比较并讨论了配位前后标题化合物主要的键性质的变化。  相似文献   
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