硝酸根和铅离子的络合物的极谱研究

采用蒋和徐提出从极谱半波电势求络离子的逐级稳定常数的方法,研究铅离子和硝酸根的络合物,测得PbNO_3~+、Pb(NO_3)~2和Pb(NO_3)_3~-的逐级稳定常数分别为:K_1=2.34,K_2=1.30,K_3=3.25.     

基于8-羟基喹啉衍生物镉配合物制备与晶体结构

以季铵盐配体L与Cd(NO_3)_2·4H_2O反应得到配合物[Cd(L)(NO_3)(H_2O)]·NO_3,并通过X射线衍射、红外光谱、质谱等表征了结构.单晶衍射结果表明中心原子Cd(Ⅱ)与去质子化的L~-的3个O原子和一个N原子,1个单齿配位的硝酸根,1个水的O原子和相邻配体2-吡啶N原子配位,形成一维链状结构.晶体属单斜晶系,Pn空间群,晶胞参数a=0.763 54(6)nm,b=0.912 15(7)nm,c=1.856 50(14)nm,α=90.00,β=91.524 0(10),γ=90.00,V=1.292 53(17)nm~3,Z=2,D_c=1.780 g/cm~3,μ=0.921 mm~(-1),F(000)=696,GOF on F~2=1.023,~aR_1[I2σ(I)],wR_2=0.037 7,0.090 6,R_1[all data],wR_2=0.043 7,0.094 4.     

金属络合物的极谱研究Ⅳ.——亚铊与硫氰酸根的络合物

本文用极谱法证明亚铊离子与硫氰酸根在水溶液中生成配位数自1至6的六种络合物,它们的稳定常数依次为K_1=4.38±0.04,K_2=7.59±0.18,K_3=5.04±0.19,K_4=5.37±0.42,K_5=3.33±0.52,K_6=2.88±0.93,     

金属络合物的极谱研究 Ⅴ.铅、锌和硫氰酸根的络合物

用极谱法测定硫氰酸铅络合物的各级稳定常数,结果如次:K_1=6.03,K_2=9.77,K_3=9.27,K_4=8.34,K_5=7.26,K_6=4.30(25℃,用高氯酸纳维持μ=3).又用同法测定硫氰酸锌络合物的各级稳定常数如下:K_1=0.724,K_2=7.94,K_3=15.8,K_4=19.5,K_5=16.6,K_6=4.3(25℃,用高氯酸钠维持μ=3).     

分析化学试题答案

一、选择:1.C;2.A;3.B,A;4.B;5.HCl,甲基橙,不需准确加入6.C,增大试样量二、埴空:1.[H~+]+[H_2PO_4~-]+2[H_3PO_4]=[OH~-]+[NH_3]+[PO_4~(3-)];2.HCN;3.H_2PO_4~-;4.平均值26.03％,标准偏差S=0.02％,变异系数=0.08％;5.K_1=10~(9.54),K_2=10~(8.93),K_3=10~(2.73),K_4=10~(2.08),logβ_1=9.54,logβ_2=18.47,logβ_3=21.20,logβ_4=23.28,α=10~(8.47)     

膜透析处理样品-离子色谱法测定奶粉中亚硝酸盐和硝酸盐

采用膜透析处理样品-离子色谱法测定奶粉中亚硝酸盐和硝酸盐的含量。利用截留分子量为(3.5~5)kD的透析膜处理奶液,透析液经0.22μm滤膜过滤后,以不同浓度的氢氧化钾溶液为淋洗液,用紫外检测器在波长210nm处分别测定NO_2~-和NO_3~-,其线性范围依次为0.02~0.5mg·L~(-1),0.2~5.0mg·L~(-1),检出限(3S/N)依次为0.01,0.008 mg·L~(-1)。经用于实样分析,NO_2~-和NO_3~-测定值的相对标准偏差(n=6)分别为2.7%,1.9%。加标回收率在90.7%~105%之间。     

石墨炉原子吸收光谱法直接测定生物样品痕量硒

近年研究表进,克山病,大骨节病和动物的白肌病是与硒量低有密切的关系。因此,生物体内痕量硒的测定,引起人们的重视和兴趣。由于硒的挥发性和基体干扰,影响石墨炉原子吸收法直接测定的准确性。基体改进剂的使用,能改善分析灵敏度。Ni(NO_3)_2是最常用的基体改进剂。Wely等提出用Mg(NO_3)_2和Cu(NO_3)_2作混合基体改进剂,可有效地稳定不同价态的Se挥发。本文比较了几种基体改进剂消除干扰的效果,用Ni(NO_3)_2和K_2ptCl_6为混合基体改进剂,直接测定血液和白内障中痕量硒,获得满意的结果。     

A New Cd(Ⅱ) Coordination Polymer Constructed by 1,10-Phenanthroline Derivative: Syntheses,Structure, Physical Properties and Theoretical Calculation

A new Cd(Ⅱ) coordination polymer, [Cd(L)_2(H_2O)]_n(1), has been hydrothermally synthesized by using 1-(1 H-imidazo[4,5-f][1,10]phenanthrolin-2-yl)naphthalen-2-ol(HL),(3-(4-(carboxymethoxy)phenyl)acrylic acid and Cd(NO_3)·4 H_2O. It crystallizes in monoclinic, space group P2_(1/c) with a = 19.41(2), b = 11.078(12), c = 20.09(2) ?, β = 116.824(17)o, V = 3855(7) ?~3, Z = 4, C_(46)H_(28)CdN_8O_3, Mr = 853.17, Dc = 1.470 g/cm~3, F(000) = 1728, μ(Mo Ka) = 0.621 mm~(-1), R = 0.0338 and wR = 0.0890. 1 shows a one-dimensional(1 D) zigzag chain structure. The neighboring chains are extended into a two-dimensional(2 D) layer structure by π-π interactions between adjacent L ligands. In addition, Natural Bond Orbital(NBO) analysis was performed by the B3LYP/LANL2DZ method in Gaussian 09 Program. The calculation results show the obvious covalent interaction between the coordinated atoms and Cd(Ⅱ) ion.     

LDH-[Cd(H_2O)W_(11)NiO_(39)]~(8-)复合材料的合成、表征及光催化活性

用离子交换法制备了LDH-[Cd(H_2O)W_(11)NiO_(39)]~(8-)复合材料,并利用IR,XRD,N_2吸附和脱附实验以及扫描电镜配合X-射线能量色谱仪(SEM-EDS)等方法对其结构和性质进行了表征.结果表明,[Cd(H_2O)W_(11)NiO_(39)]~(8-)杂多阴离子取代了黏土板层中的NO_3~-离子,并且仍然保留了Keggin结构.利用合成的复合材料LDH-[Cd(H_2O)W_(11)NiO_(39)]~(8-)作为催化剂,对亚甲基蓝进行了光催化降解实验,并确定了光降解反应的最佳反应条件.在最佳反应条件下,亚甲基蓝的脱色率可达97.11%.并将复合材料与杂多酸盐和黏土的光催化活性进行了比较,其光催化活性顺序为LDH-[Cd(H_2O)W_(11)NiO_(39)]~(8-)K_8[Cd(H_2O)W_(11)NiO_(39)]Zn_2Al黏土.因此,LDH-[Cd(H_2O)W_(11)NiO_(39)]~(8-)复合材料具有优异的光催化活性.     

[(Et_4N)_1.5{Li(H_2O)_6}0.5][Cd_2(SC_6H_4Bu~t-4)_6]·C_2H_5OH双核镉配合物的合成与晶体结构

标题化合物由4-Bu'S_6H_4SLi、Cd(NO_3)2·4H_2O和Et.NBr反应制备。用X射线单晶衍射法测定其晶体结构。     

Synthesis,Crystal Structure and Gas Adsorption of a Two-fold Interpenetrated Three-dimensional Framework {[Cd(2-NO_2-BDC)(4,4?-DPA)]·(DMF)}_n

The reaction of Cd(NO_3)_2·4H_2O with 4,4?-dipyridylacetylene(4,4?-DPA) and 2-nitroterephthalic acid(2-NO_2-H_2BDC) in DMF/H_2O mixed solvent has afforded a compound {[Cd(2-NO_2-BDC)(4,4?-DPA)]·(DMF)}_n(1). Compound 1 has been characterized by single-crystal X-ray diffraction, powder X-ray diffraction, thermogravimetry analysis, and IR spectrum. Compound 1 crystallizes in the monoclinic system, space group P21/n, with a = 12.1488(3), b = 14.6689(3), c = 13.1615(3) ?, β = 111.809(3)o, V = 2177.63(9) ?~3, Z = 4, C_(23)H_(18)N_4O_7 Cd, M_r = 574.81, D_c = 1.753 g/cm~3, μ = 8.523 mm~(-1), F(000) = 1152, the final R = 0.0411 and wR = 0.1064 for 3589 observed reflections with I 2s(I). In compound 1, the Cd(Ⅱ) ions are linked by the carboxylate groups of 2-NO_2-BDC ligands to give a two-dimensional layered structure based on the centrosymmetric dinuclear Cd_2(COO)_2 units, which are further connected by the 4,4?-DPA ligands to produce a three-dimensional framework with pcu topology. Careful examination revealed that compound 1 is a 2-fold interpenetrating framework. Furthermore, the gas adsorption properties of 1 for N_2 and CO_2 have also been investigated.     

一种镉(Ⅱ)配位聚合物的合成及其作为Fe3+和Mn2+双响应荧光化学传感器的表现

以三(4-(1H-咪唑-1-基)-苯基)胺(Tipa),富马酸(H_2fuma)和Cd(NO_3)_2·6H_2O为原料,溶剂热法在100℃下合成了一种新的Cd(Ⅱ)配合物[Cd(fuma)(Tipa)_3Cl]_n(CP1),其结构经X-射线单晶衍射,IR,元素分析表征。CP1属单斜晶系,C 2/c空间群,晶胞参数a=21.5503(10)?,b=14.9847(6)?,c=18.2554(10)?,α=90°,β=99.687(5)°,γ=90°。固体荧光激发依赖测试结果显示配合物CP1对激发光具有依赖性,并研究了其变温荧光,液体荧光的测试结果显示,CP1可以作为检测Fe~(3+)和Mn~(2+)离子的双响应荧光化学传感器。     

Crystal Structure and Luminescent Properties of a 3D Cd(Ⅱ) Compound Constructed from Succinate and 3,6-Di(4-pyridyl)pyridazine

A three-dimensional(3D) coordination polymer,[Cd(SC)(DPPD)]_n(1,H_2SC = succinic acid and DPPD = 3,6-di(4-pyridyl)pyridazine),has been synthesized by the solvothermal reaction of Cd(NO_3)_2·4H_2O with H_2 SC and DPPD at 120 oC in DMF solvent. Compound 1 crystallizes in the monoclinic system,space group P2_1/c,with a = 10.7993(4),b = 11.7705(3),c = 13.5336(6) ?,V = 1678.89(11) ?~3,Z = 4,C18H14N4O_4 Cd,M_r = 462.73,D_c = 1.831 g/cm~3,μ = 1.335 mm~(-1),F(000) = 920.0,the final R = 0.0500 and wR = 0.1567 for 3714 observed reflections with I 2s(I). In compound 1,the Cd(Ⅱ) ions are linked by the SC~(2–) ligands to give a two-dimensional(2D) undulating sheet based on the centrosymmetric dinuclear Cd_2(COO)_2 units. The 2D sheets are further connected by the DPPD ligands to produce a 3D structure,which is a 6-connected(4~4·6·~(10)·8) topological network based on the dinuclear Cd_2(COO)_2 node. Compound 1 exhibits a photoluminescent emission with a maximum at 540 nm upon excitation at 460 nm.     

Hydrothermal Synthesis,Crystal structure,DFT and Application of a Dinuclear Cadmium(Ⅱ) Complex Based on NPHSNPAB

A new dinuclear cadmium(Ⅱ) complex,[Cd(NPHSNPAB)(H_2O)_2(CH_3CH_2OH)]_2(1),was synthesized by the hydrothermal reaction of N-phenyl-2-[2-hydroxyl-3-sulfo-5-nitrophenylazo]butadiene-1,3(NPHSNPAB) and Cd(NO_3)_2·4H_2O,and characterized by elemental analysis,infrared,UV-visible,fluorescence,thermal behavior and single-crystal X-ray diffraction. For this complex: C_(36)H_(42)Cd_2N_8O_(22)S_2,Mr = 1227.74,triclinic system,space group P1,a = 7.555(9),b = 12.006(14),c = 13.943(16) ?,α = 67.955(2),β = 88.573(2),γ = 77.550(2)o,V = 1142.5(2) ?~3,Z = 2,Dc = 1.784 g/cm~3,λ = 0.71073 ?,F(000) = 620,S = 1.125,R = 0.0460 and w R = 0.1159 for 3949 observed reflections with I 2(I). X-ray diffraction analysis reveals that the central Cd(Ⅱ) ion is bound by six oxygen atoms,forming a slightly distorted octahedral geometry. Density functional theory of complex 1 was studied. Noticeably,the application of 1 on metallic yarn got good effect.     

能直接用带火星的木条检验Cu(NO_3)_2受热分解产生的氧气吗

高中化学乙种本上册161页[实验6—6]用Cu(NO_3)_2晶体代替KNO_3,做加热分解实验。人们常常直接用带火星的木条去检验Cu(NO_3)_2分解后所得到的混合气体中的氧气。我们认为这种做法是错误的。 1.从反应的方程式上看 2Cu(NO_3)_2=2CuO+4NO_2↑+O_2↑在反应后的混合气体中,氧气所占的体积比为20％,而在空气中,氧气所占的体积比     

氮、硫杂冠醚稀土配合物的合成、表征和结构研究

合成和表征了3个杂冠醚配体(L1:单氮杂15C5,L_Ⅱ:单氮杂18C6,L_Ⅲ:1,7—二硫杂18C6)与稀土硝酸盐的配合物:〔Ln(NO_3)_3L_Ⅰ〕(Ln=La～Pr),[Ln-(NO_3)-3L_ Ⅱ〕(Ln=La～Pr),〔HL_Ⅱ〕~+〔Ln(NO_3)_4(OH_2)_2〕~-(Ln=Nd,Sm～Er,Yb),〔Ln(NO_3)_3.L_Ⅲ’(H_2O)](Ln=La～Nd,Sm～Er,Yb),其中L_Ⅲ’表示L_Ⅲ冠醚环上的2个硫原子在与稀土硝酸盐反应的过程中被氧化为亚砜.配合物〔HL_Ⅱ〕~+[Nd(NO_3)_4-(OH_2)_2]的晶体属单斜晶系,空间群P2_1/n,a=1.644 0(5),b=1.739 2(3),c=1.867 5(4)nm,β=107.26(2)°.Z=8,Nd~(+3)与4个二齿NO_3~-和2个水分子配位,形成长链状夹心式结构;配合物〔Er(NO_3)_3L_Ⅲ’(H_2O)〕·CH_3COCH_3的晶体为P2_1/n空间群,a=0.877 2(2),b=1.817 9(7),c=1.854 0(5)nm,β=103.50(3)°,Z=4,Er~(3+)与3个二齿NO_3~-、1个水分子及2个亚砜氧原子形成配位数为9的配合物.     

三硫氰酸根三乙二胺合镉(Ⅱ)钾(Ⅰ)的晶体结构

含钾和二价金属离子的双金属硫氰酸根配合物的晶体结构究研已有一些报道.在K_2Pb(SCN)~4和K_2Cd(SCN)_4·2H_2O这两个化合物中,晶体结构都是由K~+和M(SCN)_4~(2-)组成.本文报道了Cd(en)_3K(NCS)_3的晶体结构,其基本构型与上述两个化合物有显著的不同(en为乙二胺).     

Synthesis,Crystal Structure and Properties of a 3-Fold Interpenetrating 3D Cd(Ⅱ) Complex Derived from 4-(2-Methyl-1H-imidazol-1-yl)benzoic Acid

A new Cd~Ⅱ coordination complex,namely [Cd(iba)_2]_n(1),was prepared by the hydrothermal reaction of Cd(NO_3)_2·4H_2O with 4-imidazol-1-yl-benzoic acid(Hiba). Single-crystal X-ray diffraction analysis shows that compound 1 crystallizes in monoclinic system,space group Cc with a = 11.403(4),b = 30.480(9),c = 7.732(3) ?,β = 130.189(4)o,V = 2503.0(1) ?~3,Z = 4,C_(22)H_(18)CdN_4O_4,Mr = 514.80,Dc = 1.666 g/cm~3,F(000) = 1032 and μ(Mo Kα) = 1.101 mm-1. The final R and wR are 0.0573 and 0.1823 for 4421 observed reflections with I 2σ(I). Each iba-ligand coordinates in a bidentate fashion,connecting the Cd(Ⅱ) atoms to form a 2D wave-shape layer structure,which can be simplified as a four-connected topological net. Interestingly,the 2D layers are further extended into a 3-fold interpenetrating 3D architecture. Compound 1 displays an emissive maximum at 455 nm in the solid state at room temperature and a response of the second harmonic generation(SHG) activity is approximately 0.8 times that of KDP.     

稀土硝酸盐与含氮冠醚（2,2）配合物的合成及其晶体结构

用X射线衍射法测定了稀土硝酸盐与冠醚(2,2)配合物Ln(NO_3)_3·(2,2)(Ln=Ce、Pr、Nd)的晶体结构。发现配合物具有与Eu(NO_3)_3(2,2)不同的配位方式。用“堆积比饱和规律”对结构差异原因作了初步的讨论。配合物均属三斜晶系空间群P,Z=2。     

硫氰化铁—亚硝酸盐的催化比色法测定土壤中碘的含量

土壤中碘的测定,一般方法较繁或需特定的蒸馏装置。但用硫氰化铁-亚硝酸盐催化比色法测定碘却简单、快速和灵敏。在稀硝酸溶液中,存在适量NO_2~-的情况下,碘化物可加速硫氰化铁的褪色速度。土壤中的碘用K_2CO_3固定,灰化除去有机物,然后定容,取清液利用该法测定碘含量。本法最低检出量为0.02μg,回收率在80%以上,变异系数为4.13%。