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1.
The CaCl2-(NH4)2HPO4-(C6H11NO4)n-NH3-H2O system at 25°C was studied by the solubility (Tananaev’s residual concentrations) technique and pH measurements. The parameters providing for the coprecipitation of nanocrystalline (12.5–18.7 nm) calcium and chitosan hydroxylapatites were found. Calcium-deficient chitosan hydroxylapatites Ca9.8(PO4)6(OH)1.6 · xC6H11NO4 · yH2O, where x = 0.075 or 0.37 and y = 5.8 or 6.2, and stoichiometric calcium hydroxylapatites Ca10(PO4)6(OH)2 · xC6H11NO4 · yH2O, where x = 0.075, 0.1, 0.2, 0.37, 0.5, or 0.75 and y = 5.7–7.5, were synthesized. Solid phases were characterized by chemical analysis, X-ray powder diffraction, thermogravimetric analysis, and IR spectroscopy.  相似文献   

2.
The synthesis and physicochemical characterization of nanocomposites of calcium hydroxylapatite-chitosan-multiwall carbon nanotubes (CNTs) was performed. The CaCl2-(NH4)2HPO4-(C6H11NO4) n -CNT-NH3-H2O system was studied by the solubility (Tananaev’s residual concentration) method and pH measurements at 25°C. Conditions for the joint precipitation of nanocrystalline calcium hydroxylapatite, chitosan, and multiwall CNTs were found. Nanocomposites with the general formula Ca10(PO4)6(OH)2 · x(C6H11NO4) · yCNT · zH2O, where x = 0.1, 0.2, and 0.5; y = 0.5, 2.0, 4.0, and 5.0; and z = 5.9–7.9. The solid phases were characterized by chemical, thermogravimetric, and X-ray diffraction analysis and IR spectroscopy.  相似文献   

3.
The CaCl2-(NH4)2HPO4-NH4HCO3-(C6H11NO4) n -H2O system at 25°C has been investigated by the solubility (Tananaev’s residual concentration) method and pH measurements. Coprecipitation conditions have been determined for nanocrystalline type A and B calcium carbonate apatites. Type A: Ca10(PO4)6(CO3) x (OH)2 − 2x · yC6H11NO4 · zH2O (x = 0.2, 0.5, 1.0; y = 0.1, 0.3, 0.5; z = 5.3−6.7); type B: Ca10[(PO4)5.7(CO3)0.45]CO3 · 0.3C6H11NO4 · 9H2O, and Ca10[(PO4)5.55(CO3)0.675]CO3 · 0.3C6H11NO4 · 9.2H2O. The solid phases have been characterized by chemical analysis, X-ray diffraction, thermogravimetric analysis, and IR spectroscopy.  相似文献   

4.
Nanocomposites (NCs) based on carbonated calcium hydroxyapatite (CHA) (bioapatite, an analogue of the inorganic component of mammalian bone tissue), carbonate apatite (Ca10(PO4)6CO3, CA), and multiwall carbon nanotubes (CNTs) are prepared in the system CaCl2–(NH4)2HPO4–NH4HCO3–NH3–CNT–H2O (25°C) by coprecipitation of calcium and phosphorus salts with CNTs from aqueous solutions. The physicochemical properties of nanocomposites are studied as dependent on their formation conditions and composition using the solubility (residual concentrations) method and pH measurements. The composition, crystal structure, morphology, spectroscopic and thermal characteristics of the synthesized CHA/CNT and CA/CNT NCs are determined using chemical analysis, X-ray powder diffraction, thermal analysis, and IR spectroscopy. Either CHA/CNT NCs of composition Ca10(PO4)6(CO3)x(OH)2–2х · yCNT · zH2O, where х = 0.2; 0.5; 0.8; y = 1, 2, 3; z = 6.8–10.8, or (when х = 1) CA/CNT NCs of composition Ca10(PO4)6CO3 · yCNT · zH2O, where y = 1–3; z = 6.9–10.8, are formed as the carbonate and CNT contents of the NC increase. Our results favor the understanding of the effect of carbonization and CNTs on the metabolic formation of native bone tissue apatite and can be used for the design of efficient ceramics for bone implants.  相似文献   

5.
A new approach to the preparation of lanthanide catalysts for the synthesis of nitrogen heterocycles (exemplified by 2-propyl-3-ethylquinoline) was developed based on the reactions of LnCl3 · 6H2O crystalline hydrates with alkylaluminums. It was found that the interaction of LnCl3 · 6H2O (Ln = Ce, Pr, Tb, and Eu) with iso-Bu3Al in aromatic solvents (20°C) resulted in the formation of soluble (isobutane and the alumoxane (iso-Bu2Al)2O) and insoluble products (with the empirical formula LnCl3 · xH2O · y(iso-Bu2Al)2O (x = 0.4–0.7; y = 0.04–0.07)). The physiochemical properties of LnCl3 · xH2O · y(iso-Bu2Al)2O were studied, and these compounds were found to be highly efficient catalysts for the reaction of aniline condensation with butyraldehyde to form 2-propyl-3-ethylquinoline.  相似文献   

6.
Calcium hydroxyapatite/multiwall carbon nanotubes/collagen nanocomposites were synthesized and subjected to physicochemical analysis. The system CaCl2-(NH4)2HPO4-multiwall carbon nanotubes-NH3-H2O-collagen was investigated at 25°C by the solubility method (Tananaev’s residual concentration method) and by pH measurements. Chemical, X-ray powder diffraction, and thermogravimetric analyses and IR spectroscopy showed that, in the system CaCl2-(NH4)2HPO4-multiwall carbon nanotubes-NH3-H2O-collagen under chosen synthesis conditions, nanocomposites comprising nanocrystalline calcium hydroxyapatite (NCHA), multiwall carbon nanotubes (CNT), and collagen form with the composition Ca10(PO4)6(OH)2 · xCNT · yH2O · z collagen, where x = 1–5; y = 5.5–7.7, and z = 3, 5, and 10 wt %. The obtained nanocomposites are the products of the coprecipitation of CNT, collagen, and NCHA, which forms in the system by the interaction of CaCl2 and (NH4)2HPO4.  相似文献   

7.
The interaction in the CaCl2-MgCl2-(NH4)2HPO4-NH3-H2O and CaCl2-MgCl2-(NH4)2HPO4-(C6H11NO4) n -NH3-H2O systems at 25°C has been investigated by the solubility (Tananaev’s residual concentration) method and by pH measurements. Magnesium-containing calcium hydroxylapatites with the general formula Mg x Ca10 − x (PO4)6(OH)2 · nH2O (x = 0.05, 0.1, 0.2, 0.3; n = 6–7.3) and magnesium- and chitosan-containing calcium hydroxylapatites with the general formula Mg x Ca10 − x (PO4)6(OH)2 · y(C6H11NO4) · nH2O (x = 0.05, 0.1, 0.2, 0.3; y = 0.1, 0.3, 0.46; n = 6–8.3) have been isolated in the nanocrystalline state. The solids have been characterized by chemical and thermogravimetric analyses, X-ray diffraction, and IR spectroscopy.  相似文献   

8.
A series of seven novel f-element bearing hybrid materials have been prepared from either methyl substituted 3,4 and 4,5-pyrazoledicarboxylic acids, or heterocyclic 1,3- diketonate ligands using hydrothermal conditions. Compounds 1, [UO2(C6H4N2O4)2(H2O)], and 3, [Th(C6H4N2O4)4(H2O)5]·H2O feature 1-Methyl-1H-pyrazole-3,4-dicarboxylate ligands (SVI-COOH 3,4), whereas 2, [UO2(C6H4N2O4)2(H2O)], and 4, [Th(C6H5N2O4)(OH)(H2O)6]2·2(C6H5N2O4)·3H2O feature 1-Methyl-1H-pyrazole-4,5-dicarboxylate moieties (SVI-COOH 4,5). Compounds 5, [UO2(C13H15N4O2)2(H2O)]·2H2O and 6, [UO2(C11H11N4O2)2(H2O)]·4.5H2O feature 1,3-bis(4-N1-methyl-pyrazolyl)propane-1,3-dione and 1,3-bis(4-N1,3-dimethyl-pyrazolyl)propane-1,3-dione respectively, whereas the heterometallic 7, [UO2(C11H11N4O2)2(CuCl2)(H2O)]·2H2O is formed by using 6 as a metalloligand starting material. Single crystal X-ray diffraction indicates that all coordination to either [UO2]2+ or Th(IV) metal centers is through O-donation as anticipated. Room temperature, solid-state luminescence studies indicate characteristic uranyl emissive behavior for 1 and 2, whereas those for 5 and 6 are weak and poorly resolved.  相似文献   

9.
A new borophosphate compound with the composition (NH4) χ Mn((3?χ)/2)(H2O)2 [BP2O8]·(1?x)H2O was prepared under mild hydrothermal conditions and characterized by X-ray powder diffraction (XRD) and Fourier Transform Infrared Spectroscopy (FTIR) methods. The title compound was synthesized from MnCl2·2H2O, H3BO3, and (NH4)2HPO4 with variable molar ratios by heating at 180 °C for 7 days in an autoclave. The X-ray diffraction data of the water insoluble polycrystalline powder was indexed using the TREOR program in hexagonal system with the unit cell parameters of a = 9.5104, c = 15.7108 Å, Z = 6 and the space group P65 (No.176). (NH4) χ Mn((3?χ)/2)(H2O)2 [BP2O8]·(1?x)H2O is isostructural with (NH4) χ M ((3?χ) 2)/II (H2O)2 [BP2O8]·(1?x)H2O (MII = Co, Cd, Mg; x = 0.5–1). Its unit cell parameters and hkl values were in good agreement with the other isostructural compounds. This is the first report presenting both the synthetic details and the indexed X-ray powder diffraction pattern of this compound along with the characterization by FTIR, thermal gravimetric analysis, scanning electron microscopy and EPR.   相似文献   

10.
The following adducts of cucurbit[6]uril and cucurbit[8]uril with triangular cluster chloroaquacomplexes have been prepared and characterized: {[Mo3S4(H2O)7Cl2]2(CB[6])}Cl4·13H2O (I), (H3O)2{[Mo3Se4×(H2O)6Cl3](CB[6])}Cl3·3.5H2O (II) and (H3O)2{[Mo3S4(H2O)4Cl5](CB[8])}Cl·14H2O (III). It is shown that the formation of complementary hydrogen bonds in the systems cucurbit[6]uril/[M3Q4(H2O)9?x Clx](4?x)+ (x = 1–3) results in a selective isolation of isomers containing chlorine atom in the trans-position to the capping μ3-ligand. For large x, a selective inclusion of one or another form into the supramolecular compound is also affected by other factors (a system of hydrogen bonds, S?S and S…Cl interactions between cluster complexes, packing effects etc.).  相似文献   

11.
The synthesis and characterization of lanthanide(III) citrates with stoichiometries 1:1 and 2:3; [LnL·xH2O] and [Ln2(LH)3·2H2O], Ln=La, Ce, Pr, Nd, Sm and Eu are reported. L stands for (C6O7H5)3? and LH for (C6O7H6)2?. Infrared absorption spectra of both series evidence coordination of carboxylate groups through symmetric bridges or chelation. X-ray powder patterns show the amorphous character of [LnL·xH2O]. The compounds [Ln2LH3·2H2O] are crystalline and isomorphous. Emission spectra of Eu compounds suggest C 2v symmetry for the coordination polyhedron of [LnL·xH2O] and C 4v for [Ln2(LH)3·2H2O]. Thermal analyses (TG-DTG-DTA) were carried out for both series. The thermal analysis patterns of the two series are quite different and both fit in a 4-step model of thermal decomposition, with lanthanide oxides as final products.  相似文献   

12.
The arsenomolybdates [H2As2Mo6O26(H2O)] · (H2biyb)2 · 2H2O ( 1 ) and [H3As2Mo6O26] · (H3pt)2 ( 2 ) [biyb = 1,4‐bis(imidazol‐1‐ylmethyl)benzene, pt = 4′‐(3′′‐pyridyl)‐2,3′:6′3′′‐terpyridine] were synthesized via hydrothermal method. The structures of the compounds were characterized by single‐crystal X‐ray diffraction analyses, elemental analyses, IR spectroscopy, and TG analysis. Compounds 1 and 2 exhibit two isomeric forms of [HxAs2Mo6O26](6–x)–. The structure of 1 is constructed from the B‐type [H2As2Mo6O26(H2O)]4– polyanions and free biyb ligands via weak interactions to form 3D supramolecular framework with a {3 · 4 · 53 · 6}{3 · 43 · 52}{3 · 5 · 6}2{3 · 52}2 topology structure. In compound 2 , the A‐type [H3As2Mo6O26]3– clusters are surrounded by pt ligands through hydrogen bond interactions forming 3D supramolecular framework with a {43 · 63}2{46 · 66 · 83} topology structure. The electrochemical behaviors, electrocatalytic and photocatalytic activities of 1 and 2 are detected.  相似文献   

13.
The synthesis, structural, and magnetic characterization of five new members of the hexanuclear oximate [MnIII6] family are reported. All five clusters can be described with the general formula [MnIII6O2(R-sao)6(R′-CO2)2(sol)x(H2O)y] (where R-saoH2 = salicylaldoxime substituted at the oxime carbon with R = H, Me and Et; R′ = 1-naphthalene, 2-naphthalene, and 1-pyrene; sol = MeOH, EtOH, or MeCN; x = 0–4 and y = 0–4). More specifically, the reaction of Mn(ClO4)2·6H2O with salicylaldoxime-like ligands and the appropriate carboxylic acid in alcoholic or MeCN solutions in the presence of base afforded complexes 15: [Mn6O2(Me-sao)6(1-naphth-CO2)2(H2O)(MeCN)]·4MeCN (1·4MeCN); [Mn6O2(Me-sao)6(2-naphth-CO2)2(H2O)(MeCN)]·3MeCN·0.1H2O (2·3MeCN·0.1H2O); [Mn6O2(Et-sao)6(2-naphth-CO2)2(EtOH)4(H2O)2] (3); [Mn6O2(Et-sao)6(2-naphth-CO2)2(MeOH)6] (4) and [Mn6O2(sao)6(1-pyrene-CO2)2(H2O)2(EtOH)2]·6EtOH (5·6EtOH). Clusters 3, 4, and 5 display the usual [Mn6/oximate] structural motif consisting of two [Mn3O] subunits bridged by two Ooximate atoms from two R-sao2? ligands to form the hexanuclear complex in which the two triangular [Mn3] units are parallel to each other. On the contrary, clusters 1 and 2 display a highly distorted stacking arrangement of the two [Mn3] subunits resulting in two converging planes, forming a novel motif in the [Mn6] family. Investigation of the magnetic properties for all complexes reveal dominant antiferromagnetic interactions for 1, 2, and 5, while 3 and 4 display dominant ferromagnetic interactions with a ground state of S = 12 for both clusters. Finally, 3 and 4 display single-molecule magnet behavior with Ueff = 63 and 36 K, respectively.  相似文献   

14.
Substitutional solid solutions (Cu1−y Zn y )2(OH)PO4·xH2O (0 ≤ y ⩽ 0.26, x = 0.1−0.2), (Cu1−y Co y )2(OH)PO4·xH2O (0 ≤ y ≤ 0.10, x = 0.1−0.2), and (Cu1−y Ni y )2(OH)PO4·xH2O (0 ≤ y ≤ 0.08, x = 0.1−0.2) were synthesized. The unit cell parameters of the resulting phosphates were determined, and their IR absorption spectra were measured. The reactants were H3PO4 and mixtures of hydrous carbonates of the appropriate metals. Thermolysis of the solid solutions was examined with (Cu1−y Co y )2(OH)PO4·xH2O (0 ≤ y ≤ 0.10, x = 0.1−0.2) as an example.  相似文献   

15.
Three Mn(II) polymers Mn(H2O)4(C5H6O4) 1, [Mn(H2O)2(C5H6O4)]·H2O 2 and Mn(H2O)(C6H8O4) 3 were synthesized (H2(C5H6O4) = glutaric acid, H2(C6H8O4) = adipic acid) under mild ambient conditions. The [Mn(H2O)2]2+ units in 2 are interlinked by the glutarate anions with a η4μ3 bridging mode to form 2D (4·82) topological networks, which are stacked via interlayer hydrogen bonds into a 3D (43·65·82)(47·63) topological net. Compound 3 crystallizes in the acentric space group P21 and exhibits significant ferroelectricity (remnant polarization Pr = 0.371 nC cm−2, coercive field Ec = 0.028 kV cm−1, saturation of the spontaneous polarization Ps = 0.972 nC cm−2). The adjacent MnO6 octahedrons in 3 are one atom-shared to generate the Mn2O11 bi-octahedron, leading into 1D metal oxide chains. The resulting chains are interconnected by the η5μ5 adipate anions to form new 2D (48·62) networks, which are held together via strong interlayer hydrogen bonds into 3D α-Po topological supra-molecular architecture. The temperature-dependent magnetic susceptibility data of 13 shows overall anti-ferromagnetic interactions between the metal ions bridged by the carboxylate groups.  相似文献   

16.
trans‐Bis(3‐isopropyl‐7‐oxocyclohepta‐1,3,5‐trien‐1‐olato)copper(II) trans‐bis(3‐isopropyl‐7‐oxocyclohepta‐1,3,5‐trien‐1‐olato)palladium(II) as the (5/1) and (3/2) composites [Cu(C10H11O2)2]·0.2[Pd(C10H11O2)2] and [Cu(C10H11O2)2]·0.67[Pd(C10H11O2)2], respectively, where 3‐isopropyl‐7‐oxocyclohepta‐1,3,5‐trien‐1‐olate is the systematic name for the hinokitiolate anion (hino), are the first mixed‐metal cocrystalline products isolated from the Mx(hino)y family of complexes. These cocrystals contain square‐planar trans‐Cu(hino)2 and trans‐Pd(hino)2 molecules possessing crystallographic inversion symmetry. The bulk formulation for these cocrystalline compounds is Cu1−xPdx(hino)2, where x is 0.166 (4) for the (5/1) product and 0.399 (4) for the (3/2) product. This bulk formulation is simply a convenient average expression of the whole‐molecule substitutional disorder present in these compounds. The M—O bonds are in the range 1.9210 (11)–1.9453 (10) Å, the O—M—O bite angles are in the range 82.94 (4)–83.36 (4)°, and all of the hinokitiolate O atoms are involved in C—H...O hydrogen‐bonding interactions.  相似文献   

17.
The thermal decomposition of tribochemically activated Al2(SO4)3·xH2O was studied by TG, DTA and EMF methods. For some of the intermediate solids, X-ray diffraction and IR-spectroscopy were applied to learn more about the reaction mechanism. Thermal and EMF studies confirmed that, even after mechanical activation of Al2(SO4)3·xH2O, Al2O(SO4)2 is formed as an intermediate. Isothermal kinetic experiments demonstrated that the thermochemical sulphurization of inactivated Al2(SO4)3·xH2O has an activation energy of 102.2 kJ·mol?1 in the temperature range 850–890 K. The activation energy for activated Al2(SO4)3·xH2O in the range 850–890 K is 55.0 kJ·mol?1. The time of thermal decomposition is almost halved when Al2(SO4)3·xH2O is activated mechanically. The results permit conclusions concerning the efficiency of the tribochemical activation of Al2(SO4)3·xH2O and the chemical and kinetic mechanisms of the desulphurization process.  相似文献   

18.
The crystal structure of the double copper(II) complex with borodicitric acid [Cu(H2O)5(C6H6O7)2B]+ · [(C6H6O7)2B]? · 5H2O of composition Cu[(C6H6O7)2B]2 · 10H2O has been studied by X-ray crystallography. The crystals are monoclinic, space group P21): a = 10.7852(2) ?, b = 9.9980(2) ?, c = 17.9500(5) ?; ?? = 101.126(1)°, FW = 1025.75, V = 1899.18(7) ?3, Z = 2. The dicitratoborate anions with a spirane structure have a normal geometry. The coordination polyhedron of the copper atoms is a distorted octahedron (CN 6 = 4 + 2) with an average equatorial Cu-O distance of 1.965 ± 0.023 ?. The axial positions in the CuO6 octahedron are occupied by a water molecule and an oxygen atom of one of the citrate ligands: Cu-O(5w), 2.430(3) ?; Cu-O(8), 2.382(3) ?. The crystals have an extended intricate system of hydrogen bonds consisting of 27 unique three-center O-H??O, O(w)??O, and O(w)??O(w??) bonds and four-center O(w)??O, O(w??) bonds with different structural functions.  相似文献   

19.
应用倒滴加法制备的粉状白钨酸,制备了两个新的不同组成的过氧钨酸钕:NH_4NdW_2(O_2)_5(OH)_2·4H_2O(1)和NH_4NdW_3(O_2)_3O_8·6H_2O(2)并对化合物的一些性质进行了表征。  相似文献   

20.
Reactions of a freshly prepared Zn(OH)2‐2x(CO3)x · yH2O precipitate, phenanthroline with azelaic and sebacic acid in CH3OH/H2O afforded [Zn(phen)(C9H15O4)2] ( 1 ) and [Zn2(phen)2(H2O)2(C10H16O4)2] · 3H2O ( 2 ), respectively. They were structurally characterized by X‐ray diffraction methods. Compound 1 consists of complex molecules [Zn(phen)(C9H15O4)2] in which the Zn atoms are tetrahedrally coordinated by two N atoms of one phen ligand and two O atoms of different monodentate hydrogen azelaato groups. Intermolecular C(alkyl)‐H···π interactions and the intermolecular C(aryl)‐H···O and O‐H···O hydrogen bonds are responsible for the supramolecular assembly of the [Zn(phen)(C9H15O4)2] complexes. Compound 2 is built up from crystal H2O molecules and the centrosymmetric binuclear [Zn2(phen)2(H2O)2(C10H16O4)2] complex, in which two [Zn(phen)(H2O)]2+ moieties are bridged by two sebacato ligands. Through the intermolecular C(alkyl)‐H···O hydrogen bonds and π‐π stacking interactions, the binuclear complex molecules are assembled into layers, between which the lattice H2O molecules are sandwiched. Crystal data: ( 1 ) C2/c (no. 15), a = 13.887(2), b = 9.790(2), c = 22.887(3)Å, β = 107.05(1)°, U = 2974.8(8)Å3, Z = 4; ( 2 ) P1¯ (no. 2), a = 8.414(1), b = 10.679(1), c = 14.076(2)Å, α = 106.52(1)°, β = 91.56(1)°, γ = 99.09(1)°, U = 1193.9(2)Å3, Z = 1.  相似文献   

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