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111.
AGNTO的制备和分子结构   总被引:8,自引:0,他引:8  
通过3-硝基-1,2,4-三唑-5-酮(NTO)与氨基胍重碳酸盐反应制备NTO氨基胍盐,并用X射线衍射、元素分析、红外光谱对其进行了表征.晶体属于单斜晶系,空间群为P21/n.晶体学参数为:a=0.67870(10)nm, b=2.7915(4)nm, c=1.2739(2)nm; β =96.930(10) V=2.3959(6)nm3, Z=12, Dc=1.698 g•cm -3, μ( Mo K )=1.47 cm -1, F(000)=1272.晶体结构经全矩阵最小二乘法修正,最终偏离因子R=0.0352, wR =0.0718.该盐是一种具有广泛应用前景的产气剂材料.  相似文献   
112.
通过3-硝基-1,2,4-三唑-5-酮(NTO)与碳酸锶反应,制备了标题配合物,其结构用单晶分析法测定,所得晶体学参数为:a=1.1034(1)nm,b=2.2742(2)nm,c=0.63398(9)nm,β=101.798(13)ⅲ,V=1.5573(4)nm^3,D~c=1.936g.cm^-^3,Z=2,F(000)=912,μ=35.45cm^-^1;晶体属单斜晶系,空间群为P2~1/c,最终偏离因子R为0.0344。通过标题配合物在水中溶解焓的测定,算得其标准生成焓、晶格焓、晶格能和标准脱水焓。  相似文献   
113.
The title compound, C40H39N2B, Mr=558.54, crystallizes in space group P21/c, monoclinic, a=18.013(3), b=10.821(2), c=17.321(3),β=112.20(1)°, V=3125.9(9)3, Z=4, Dc=1.187g/cm3, μ(MoKα)=0.068mm-1, F(000)=1192. The final R and wR(F2) are 0.0467 and 0.0972 for 2353 observed reflections (I>2σ(I)), respectively. In the title molecule, the pyridyl ring of the cation makes dihedral angle of 19.94° with the phenyl ring. The anion takes a slightly distorted tetrahedral geometry. In the crystal, along the screw axis b, the centrosymmetric anion pairs form double chains, which are in turn related by the glide plane c, forming double layers. The centrosymmetric cation pairs are related by screw axis b and located between the double sheets of the anion.  相似文献   
114.
合成了标题所示的一系列新的含三(取代吡唑)硼氢根的金属配合物,均通过元素分析、IR、1H NMR进行表征.配合物[η3-HB(3-(2'-thie)-5-Mepz)3]Zn(NO3)·1/2THF(2c)的晶体结构测定表明,硝酸根是以不对称双齿方式与Zn原子配位(Zn-O(2)键长为0.1966(4)nm,Zn-O(3)键长为0.2463(4)nm);而在镉的类似物{[η3-HB(3-Ph-5-Mepz)3]Cd(NO3)(THF)}(2e)中,NO-3则以双齿方式与Cd原子配位[Cd-O键长为0.2334(3)和0.2356(3)nm].NO-3随金属不同取不同方式配位的现象,为解释锌、镉碳酸酐酶的不同活性(与酶活性中心配位的HCO-3是NO-3的等电子体)提供了进一步的依据.配合物2c和2e均为三斜晶系,P-1空间群,Z=2.2c晶胞参数:a=1.16250(10),b=1.2422(2),c=1.32590(10)nm;α=71.410(10)°,β=73.090(10)°,γ=65.660(10)°;R=0.0755.2e品胞参数:a=1.13030(10),b=1.2099(2),c=1.2607(2)nm;α=102.050(10)°,β=91.780(10)°,γ=93.620(10)°;R=0.0302.  相似文献   
115.
Yuan  Ai-Hua  Lu  Lu-De  Shen  Xiao-Ping  Chen  Li-Zhuang  Yu  Kai-Bei 《Transition Metal Chemistry》2003,28(2):163-167
A cyanide-bridged FeIII–FeII mixed-valence assembly, [FeIII(salen)]2[FeII(CN)5NO] [salen = N,N-ethylenebis(salicylideneiminato)dianion], prepared by slow diffusion of an aqueous solution of Na2[Fe(CN)5NO] · 2H2O and a MeOH solution of [Fe(salen)NO3] in an H tube, has been characterized by X-ray structure analysis, i.r. spectra and magnetic measurements. The product assumes a two-dimensional network structure consisting of pillow-like octanuclear [—FeII—CN—FeIII—NC—]4 units with dimensions: FeII—C = 1.942(7) Å, C—N = 1.139(9) Å, FeIII—N = 2.173(6) Å, FeII—C—N = 178.0(6)°, FeIII—N—C = 163.4(6)°. The FeII—N—O bond angle is linear (180.0°). The variable temperature magnetic susceptibility, measured in the 4.8–300 K range, indicates the presence of a weak intralayer antiferromagnetic interaction and gives an FeIII–FeIII exchange integral of –0.033 cm–1.  相似文献   
116.
The binuclear manganese(II) complex of formula [Mn2(CHZ)2(H2O)2(SO4)2] (CHZ = carbohydrazide) (1) has synthesized in aqueous solution and characterized by elemental analysis, IR, and single crystal X-ray diffraction. The compound 1 crystallizes in monoclinic system, space group P2(1)/n, a = 7.083(1) Å, b = 7.985(1) Å, c = 14.045(2) Å, β = 90.46(1)°, V = 794.42(16) Å3, Z = 2, R = 0.0308 with 1481 reflections. In the title complex, two Mn(II) cations are bonded via the bridging oxygen atoms into a centrosymmetric dimeric unit. The Mn(II) dimers are further extended into layers by means of the bridging sulfate groups. Each Mn atom in the complex is in bivalent state with a distorted pentagonal bipyramid configuration and has a N2O5 donor set which consists of two nitrogen atoms and five oxygen atoms provided by the ligands of two CHZ molecules, one water molecule, and two sulfate ions. The CHZ tridentate ligands are coordinated with adjacent Mn(II) cation via two terminal N atoms and the carbonyl O atom and sulfate anions act as bidentate bridge ligand. Four kinds of Mn(II) CHZ complex structures are compared. The thermal property of title complex was studied by using DSC and TG-DTG techniques. The results exhibit the title complex is highly stable.  相似文献   
117.
千解草(Pygmaeopremna Herbacea)为马鞭草科千解草属植物,分布在中国西南一带,尤以四川南部为多。民间用其茎叶治疗跌打损伤,风湿性关节炎,月经不调,产后瘀血,外感风寒、消化不良等病患,且疗效显著,广为应用。千解草属植物共有五种,均未见有关化学成份的报道。我们从千解草根的乙醚提取物中得到四种晶体,本文报道了具有代表性的千解草甲素的晶体和分子结构(1)。  相似文献   
118.
NTRODUCTIONItisknownthatdialkylsulfidesareefectiveextractantsfortheextractionandsepara tionofnoblemetals〔1,2〕.Paladiumcomplex...  相似文献   
119.
A novel pyrazolone derivative 2-anilino-6H-5-(1-phenyl-3-methyl-5-pyrazolone-4-ylene)-1,3,4-thiadiazine (PMCP-PTSC) containing NNS hexa-atomic heterocycle has been obtained and characterized by means of single crystal X-ray diffraction, IR and 1H NMR spectroscopies. It is interesting that when grown from two different solvents, two different crystalline structures are formed. The monoclinic crystal A belongs to a P21/c space group. The unit cell parameters are a = 16.414(4) Å, b = 12.530(3) Å, c = 8.432(1) Å, = 91.75(2) Å, and Z = 4. The triclinic crystal B belongs to a P space group. The unit cell parameters are a = 11.386(2) Å, b = 12.326(2) Å, c = 12.411(3) Å, = 83.07(1)°, = 87.76(2)°, = 86.52(2)°, and Z = 4. The structure analyses show the title compound is the keto-form. Dimers in crystal packing of A and supramolecular one-dimensional (B) concatenate structures were assembled by the intermolecular hydrogen bonds.  相似文献   
120.
A new pyridine containing compound, 4,4-bis(4-pyridylethyl)biphenyl 1, was synthesized and its structure was determined by X-ray crystallography. Two kinds of two-dimensional networks linked by hydrogen bonds were obtained with different crystal solvents: 1·2H2O, monoclinic, space group P21/n with a = 8.3280(10), b = 5.5990(10), c = 24.054(4) Å, = 98.79(2)°, V = 1108.4(3) Å3, Z = 2, Dc = 1.200 g cm–3, R1 = 0.0558; 1·CH3OH·2H2O, triclinic, space group P-1 with a = 8.3310(10), b = 12.861(2), c = 13.111(2) Å, = 64.110(10), = 75.000(10), = 83.750(10)°, V = 1220.7(3) Å3, Z = 2, Dc = 1.177 g cm–3, R1 = 0.0529. It is interesting that in the hydrate the host molecule of 1 contains an essentially flat biphenyl section, while in the methanol complex the host molecule of 1 contains a substantial twist in the center of the biphenyl section. The compounds were also characterized by NMR and FTIR spectroscopies. The 1H and 13C NMR assignments for 1 were carried out by 2D NMR spectral measurements in acetonitrile-d 3.  相似文献   
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