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1.
Antibacterial properties and toxicities were determined for 66 compounds of the 5-nitrofuran type to ascertain the connection between structure and biological activity.Unsaturated 5-nitrofuran aldehydes and some of their simplest derivatives (acetals, acylals) have high antibacterial activity and a broad spectrum. However, these compounds cannot be used in medicine because of their appreciable toxicities and low stabilities. One of the ,-unsaturated ketones in this series, 5-nitrofurfurylideneacetone, has a broad antibacterial spectrum combined with lower toxicity. Low-toxicity derivatives of 1-aminohydantoin and 3-amino-2-oxazolid-2-one are among the imino derivatives of high antibacterial activity investigated.For Part VI see [1].  相似文献   
2.
Crystalline adducts of zinc and copper(II) dithiocarbamate (Dtc) complexes with dialkylamines [M(NHR′2)(S2CNR2)2] (M = Zn, 63Cu, 65Cu; R = CH3, C2H5, or R2 = (CH2)4O; R′ = C2H5, C3H7) have been preparatively isolated. The structures and spectral properties of the adducts have been studied by EPR and 13C and 15N MAS NMR. Chemisorption of bases on powders of dinuclear dithiocarbamates leads to their dissociation into monomeric adducts. Computer simulation demonstrates that the experimental EPR spectra of isotope-substituted copper(II) adducts have an individual character. The geometry of the copper polyhedra is intermediate between a trigonal bipyramid (TBP) and a tetragonal pyramid (TP). The TBP and TP contributions have been quantified based on EPR data. 13C and 15N MAS NMR data show that the Dtc ligands incorporated into the zinc adduct molecule are structurally nonequivalent. The dependence of the isotropic 15N chemical shifts of the Dtc groups on the alkyl substituents at the nitrogen atom is interpreted based on the concept of joint manifestation of the (+)inductive effect of the alkyl substituents and the mesomeric effect of the Dtc groups.  相似文献   
3.
Russian Journal of Coordination Chemistry - Chemisorption synthesis on the basis of the binuclear compound [Bi2{S2CN(C3H7)2}6] (I) and preparative isolation of the ion-polymeric heteronuclear...  相似文献   
4.
The reaction of [Cd2{S2CN(CH2)6}4] (I) with morpholine gives a crystalline adduct of cadmium N,N-cyclo-hexamethylenedithiocarbamate [Cd{NH(CH2)4O}2{S2CN(CH2)6}2] (II), whose coordination sphere includes two molecules of the donor base. The structural organization and thermal behavior of II is studied by X-ray diffraction analysis and simultaneous thermal analysis in comparison with the original binuclear cadmium complex I. The central cadmium atom (coordination number 6) coordinates two morpholine molecules and two structurally equivalent S,S’-anisobidentate ligands HmDtc to form a chromophore [CdN2S4] with the structure of a distorted octahedron. The thermal destruction of II proceeds in two stages and includes consecutive steps of dissociation of the Cd-N bonds followed by the desorption of morpholine and thermolysis of the dithiocarbamate moiety of the adduct to form CdS as the final product. The structure of binuclear [Cd2{S2CN(CH2)6}4] is refined for a correct refinement of the geometric characteristics of compounds I and II.  相似文献   
5.
A supramolecular compound of the general formula [Zn{NH(CH2)4O} {S2CN(C2H5)2}2]4 · NH(CH2)4O · C2H4{N(CH2)4O}2 (I) was obtained and examined by X-ray diffraction analysis and thermography. According to X-ray diffraction data, the crystal lattice of compound I shows an unusual alternation of two independent centrosymmetric supramolecular complexes [Zn{NH(CH2)4O} {S2CN(C2H5)2}2]2 · C2H4{N(CH2)4O}2 (Ia) and [Zn{NH(CH2)4O} {S2CN(C2H5)2}2]2 · NH(CH2)4O (Ib). Either complex includes two molecules of an adduct of bis(diethyldithiocarbamato)zinc with morpholine and outer-sphere molecules of 1,2-dimorpholinoethane or morpholine. Adduct molecules are structurally nonequivalent in pairs and linked with solvate molecules by hydrogen bonds. The calculated geometries of the zinc polyhedra are intermediate between trigonal bipyramid and tetragonal pyramid. Thermal decomposition of supramolecular compound I proceeds through desorption of the outer-sphere and coordinated organic molecules; in the final step, defragmentation of the dithiocarbamate part gives zinc sulfide.  相似文献   
6.
The first representative of copper(II) dithiocarbamate complexes with an unusual type of structural organization is synthesized. According to the X-ray diffraction data, the layers of noncentrosymmetric mononuclear [Cu{S2CN(CH2)6}2] and centrosymmetric binuclear [Cu2?ub;S2CN (CH2)6?ub;4] molecules alternate in the crystalline lattice of copper(II) N,N-cyclo-hexamethylenedithiocarbamate. The mononuclear and binuclear forms of the complex are observed in the 2: 1 ratio. The thermal properties of the synthesized compound are studied by thermogravimetry and differential scanning calorimetry. The final product of the thermal destruction of the complex is CuS.  相似文献   
7.
The chemisorption properties of cadmium dibutyldithiocarbamate with respect to [AuCl4] in 2M HCl solutions are studied. The heterogeneous reaction of gold(III) binding affords the heteropolynuclear compound ([NH{2(C4H9)2][Au{S2CN(C4H9)2}2][CdCl4]) n (I). The molecular and crystal structures of compound I are determined from the X-ray diffraction data. Each of three ions is presented in the structure by two conformers. The irreversible decomposition of some dibutyldithiocarbamate groups is observed during the chemisorption of gold(III), which noticeably decreases the efficiency of gold binding with the sorbent studied and its sorption capacity. The study of the thermal properties of compound I shows that gold(III) is reduced to the metal during thermolysis.  相似文献   
8.
Optics and Spectroscopy - The process of extraction of the extracellular matrix (ECM) requires operational monitoring, since there is a risk of destruction of the main proteins of the cell matrix...  相似文献   
9.
Platinum(II) cyclo-hexamethylenedithiocarbamate (HmDtc) complex, [Pt{S2CN(CH2)6}2] (I), and its solvated form, Pt{S2CN(CH2)6}2] · CHCl3 (II), are synthesized and characterized by the 13C MAS NMR data. The HmDtc ligands in structure I are not equivalent, whereas the solvation of the complex is accompanied by the structural unification of the initially nonequivalent HmDtc ligands. In addition, the spectra are characterized by the 13C-195Pt spin-spin coupling. The noncentrosymmetric molecular structure of compound I determined by X-ray diffraction analysis includes two nonequivalent dithiocarbamate ligands coordinated by the metal in the S,S′-bidentate mode. The central atom forming the [PtS4] chromophore (intraorbital dsp 2-hybrid state of platinum) shifts from the plane of four sulfur atoms by 0.07 Å in the vertex of the flattened tetragonal pyramid. The seven-membered heterocycles ?N(CH2)6 of the HmDtc ligands are oppositely directed in space relative to the [S4] plane (trans orientation). The thermal behavior of compounds I and II are studied by simultaneous thermal analysis. In both cases, the final product of the multistage thermal destruction of the complexes is reduced metallic platinum.  相似文献   
10.
The interaction between cadmium cyclo-pentamethylenedithiocarbamate (chemisorbent Ia) and the [AuCl4]? anion in 2 M HCl has been investigated. The state of the chemisorbent in contact with AuCl3 solutions has been probed by 113Cd MAS NMR spectroscopy. The heterogeneous reactions in the system, including gold(III) chemisorption from the solution and partial ion exchange, yield the gold(III)-cadmium heteropolynuclear complex ([Au{S2CN(CH2)5}2]2[CdCl4]) n (I) and the polynuclear mixed-ligand complex ([Au{S2CN(CH2)5}Cl2]) n (II). The crystal and molecular structures of these compounds have been determined by X-ray crystallography. The main structural units of the compounds are the complex cation [Au{S2CN(CH2)5}2]+, [CdCl4]2? anion (in I), and Au{S2CN(CH2)5}Cl2 molecule (in II). The further structural self-organization of the complexes at the supramolecular level is due to secondary Au...S and Au...Au bonds. [Au2{S2CN(CH2)5}4]2+ dinuclear cations form in the structure of I, which then polymerize into ([Au2{S2CN(CH2)5}4]2+) n chains. In the structure of II, adjacent Au{S2CN(CH2)5}Cl2 molecules join by forming pairs of asymmetric secondary Au...S bonds, producing polymer chains with alternating antiparallel monomer units. The chemisorption capacity values calculated for cadmium cyclo-pentamethylenedithiocarbamate from gold(III) binding reactions are 455 and 910 mg of gold per gram of sorbent. The gold recovery conditions have been determined by investigating the thermal behavior of I and II by synchronous thermal analysis. The multistep thermal destruction of ionic complex I includes the thermolysis of its carbamate moiety and [CdCl4]2? (which liberates gold metal and cadmium chloride and yield some amount of CdS) and CdCl2 and CdS evaporation. The thermolysis of II proceeds via the formation of Au2S and AuCl as intermediate compounds. In both cases, the ultimate pyrolysis product is elemental gold.  相似文献   
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