Physical properties of nano-HAs/ZrO2 coating on surface of titanium materials used in dental-implants and its biological compatibility

A gradient composite coating on the surface of titanium materials, which are used in dental implants, is prepared using an electric-chemical method. The physical properties of the composite coating and its strength of combining with titanium material are studied by the scanning electron microscope, energy dispersive spectrum and X-ray diffraction analysis, etc. The results show that the nanohydroxyapatite/ZrO2 composite coating is uniformly deposited and formed on the surface of titanium materials, its strength of combining with titanium surface reaches 16.3 MPa, which is determined by the tensile test. The immersion experiment shows that a new matter of carbonate-apatite is distributed uniformly on the surface of the composite coating of nanohydroxyapatite/ZrO2. The cell experiment of cultivate exhibits that the osteoblasts MG-63 is also grown well on the surface of the composite coating. These results indicate that the nanohydroxyapatite/ZrO2 composite coating on the surface of titanium materials has a good biological activity and compatibility and could be used in the dental-implants.     

A facile one-step synthesis of TiO2/graphene composites for photodegradation of methyl orange

TiO₂/graphene composite photocatalysts have been prepared by a simple liquid phase deposition method using titanium tetrafluoride and electron beam (EB) irradiation-pretreated graphene as the raw materials. The products were characterized by X-ray diffraction, transmission electron microscopy, X-ray photoelectron spectroscopy, and thermogravimetric analysis. The effects of varying the synthesis parameters such as graphene content, concentration of titanium tetrafluoride solution and irradiation dose were investigated. It was found that the preparation conditions had a significant effect on the structure and properties of the final products. The irradiated graphene was covered with petal-like anatase TiO₂ nanoparticles, which were more uniform and smaller in size than those in products synthesized without EB irradiation-pretreated graphene. The photocatalytic activities of the products were evaluated using the photocatalytic degradation of methyl orange as a probe reaction. The results showed that the products synthesized using EB irradiation-pretreated graphene exhibited higher photocatalytic activities than those using graphene without EB irradiation pretreatment.      

Synthesis and Characterization of Nickel Nanorods Transferred from Hydrotherally Decomposed Rod-like NiS

Powders of hexagonal-structured single-crystalline nickel sulfide nanorods have been synthesized in cetyltrimethy ammonium bromide （CTAB）/water/hexane/n-pentanol quaternary microemulsion under hydrothermal conditions by using the reaction of carbamide and carbon disulfide as a sulfide source. Single-crystalline nickel nanorods have been synthesized via thermal decomposition by using single-crystalline nickel sulfide nanorods as precursor. The influence of different reaction parameters on the morphology of the products has been investigated. The structure, morphology and magnetic properties of the products were characterized by X-ray diffraction （XRD）, transmission electron microscope （TEM）, calorimeter （TGA-DSC） and vibrating sample magnetometer showed that the specific saturation magnetization （σs） and 37.5 emu/g and 68.50e, respectively. thermogravimetric analysis-differential scanning （VSM）. The results of coercivity values （Hc） magnetic measurements of nickel nanorods were     

Cerium sulfophenyl phosphate, a novel inorgano-organic solid proton-conducting material

Cerium sulfophenyl phosphate (CeSPP), a novel inorgano-organic solid proton conductor, was synthesized from the reaction of m-sulfophenyl phosphonic acid and hydrated cerous nitrate. The synthesized CeSPP was characterized by Fourier-transform infrared spectroscopy, X-ray diffraction, thermogravimetric analysis (TGA), scanning electron microscopy, and energy-dispersive X-ray spectroscopy. The TGA results reveal that CeSPP has good thermal stability. The synthesized CeSPP exhibited considerable high-proton conductivity. The proton conductivity was about 0.13 S/cm at 150 °C under 100% relative humidity. The proton conductivity at 105 °C at different RH was also measured.     

自组装花状α-Ni（OH）2和NiO的制备和表征

以硝酸镍为原料,尿素为沉淀剂,在不添加任何模板和表面活性剂条件下,采用均匀沉淀法制备出具有自组装结构的花状α型Ni(OH)2,并以其为前驱体,制得了同样具有花状结构的NiO。采用XRD、SEM、HRTEM、TG和低温液氮吸附技术对样品的晶相结构、表面形貌和孔径结构等进行表征。测试结果显示,所制备的样品是α型Ni(OH)2,比表面积是245.0m2/g,而且这些直径为4～6μm的花状Ni(OH)2是由许多纳米薄片相互组装而成。将花状Ni(OH)2在400℃焙烧2h即可获得具有花状结构的NiO,其比表面积为125.2m2/g。     

Nanohydroxyapatite synthesis using optimized process parameters for load-bearing implant

In this study, nanohydroxyapatite (NHA) was synthesized using calcium nitrate tetrahydrate and diammonium hydrogen phosphate via the precipitation method assisted with ultrasonication. Three independent process parameters: temperature (T) (70, 80 and 90°C), ultrasonication time (t) (20, 25 and 30 min), and amplitude (A) (60, 65 and 70%) were studied and optimized using response surface methodology based on 3 factors and 5 level central composite design. The responses of the model were analysed with the help of the particle size measured from field-emission scanning electron microscopy and Brunauer–Emmett–Teller (BET). The surface area of particle was measured with BET and the thermal stability of the powder was measured using thermogravimetric analysis. Finally, with the optimized process parameters obtained from the model, the NHA powder was synthesised and validated against the predicted value. The results show a good agreement with an average error 8% between the actual and predicted values. Moreover, the thermal stability and porosity of synthesized NHA was further improved after calcination. This improvement could be due to the removal of impurities from the NHA powder after calcination as indicated by the Fourier transform infrared spectroscopy and energy-dispersive X-ray spectroscopy.     

Sonochemical synthesis and characterization of disk-like copper microcrystals

Disk-like Cu microcrystals were successfully synthesized with assistance of ultrasonic irradiation. The products were characterized by means of X-ray diffraction (XRD), scanning electron microscopy (SEM), selected area electron diffraction (SAED), X-ray photoelectron spectroscopy (XPS), and thermogravimetric/differential thermal analysis (TGA/DTA). It was found that as-prepared Cu microcrystals were single crystals in nature and had a high crystallinity. They were mainly composed of disk-like and triangular Cu microcrystals with an average diameter of about 1 μm. There existed CuO on the outermost surface of the products, while a thin layer of Cu₂O was found between CuO and inner Cu microcrystals. Moreover, CTAB molecules were adsorbed on the surface of Cu microcrystals and they were desorbed while heated during TGA analysis. In addition, the influences of magnetic stirring, stillness, concentration of hexadecyltrimethylammonium bromide (CTAB) surfactant, and starting Cu salts on the morphology and size distribution of the final products have also been studied.     

One step synthesis of β-FeOOH nanowire bundles/graphene oxide nanocomposites

A nanocomposite of graphene oxide (GO) and β-ferric oxyhydroxide (β-FeOOH) nanowire bundles is synthesized by in situ hydrolysis of the precursor ferric chloride and GO nanosheets. Characterization by X-ray diffraction, transmission electron microscopy, and thermogravimetric analysis established the composite structure of the synthesized sample. The results revealed that the surface of GO nanosheets was uniformly assembled by numerous nanowire bundles with diameters in the range of 30–50 nm and lengths of 100–150 nm. Furthermore, β-FeOOH/GO nanocomposites showed a very high adsorption capacity of Congo red and thus these nanocomposites can be used as good adsorbents and can be used for the removal of organic dye from the waste water system.     

Iron nanoparticles from blood coated with collagen as a matrix for synthesis of nanohydroxyapatite

A simple wet precipitation technique was used to prepare nanobiocomposite containing iron nanoparticles coated with collagen. This nanobiocomposite was used as matrix for the synthesis of nanohydroxyapatite. The physicochemical characteristic studies of the nanohydroxyapatite thus formed were carried out using fourier transform infrared spectroscopy, transmission electron microscopy, scanning electron microscopy, energy-dispersive X-ray spectroscopy and X-ray diffraction technique to confirm the formation of hydroxyapatite on iron nanoparticle–collagen complex. The results of the above studies supported the formation of iron nanoparticle–collagen–hydroxyapatite composite. The biological studies such as biocompatibility and hemocompatibility were carried out for nanohydroxyapatite using different cell lines and blood sample. The results of biocompatibility and hemolytic assay revealed that the prepared nanobiocomposite was 100 % biocompatible and hemocompatible. This nanobiocomposite may be used for biomedical application such as injectables for targeted delivery and as scaffold for tissue engineering.     

Synthesis and characterization of PVP/TbL(phen)0.5 x 7H2O nanorods

The luminescent complex terbium (III)-trimesic acid (TMA)-1,10-phenanthroline (phen) nanorod was synthesized in the polyvinylpyrrolidone (PVP) matrix by a co-precipitation method. The chemical formula of the synthesized complex was speculated to be PVP/TbL(phen)0.5 x 7H2O by inductively coupled plasma-atomic emission spectroscopy (ICP-AES), elemental analysis and Fourier-transform infrared spectroscopy (FTIR). The X-ray diffraction pattern (XRD) of PVP/TbL(phen)0.5 x 7H2O indicated that it was a crystalline complex. The transmission electron microscopy (TEM) result showed that the complex was nanorods with diameters of about 80-100 nm. The thermogravimetric curve (TGA) analysis exhibited that the complex has good stability below 400 degrees C. UV-Vis diffuse reflectance spectra showed that there is a maximum absorption at 300 nm. The photoluminescence analyses (PLA) showed that the synthesized complex emitted the characteristic green fluorescence of Tb (III) ions under ultraviolet light excitation. The emission peaks of PVP/TbL(phen)0.5 x 7H2O at 488, 542, 581, and 618 nm using 278 nm as exciting wavelength can be assigned to the 5D4 --> 7F6, 5D4 --> 7F5, 5D4 --> 7F4, and 5D4 --> 7F3 electron transitions of the Tb3+ ions, respectively.     

Preparation of mono-dispersed carbonaceous spheres via a hydrothermal process

Mono-dispersed carbonaceous spheres (CS) with a narrow size distribution were synthesized via hydrothermal treatment of glucose. The effects of hydrothermal temperature and time, glucose concentration and pH value of solution were investigated in detail. Structures and surface properties of as-prepared products were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), Induced coupled plasma emission spectroscopy (ICP), thermogravimetric analysis/differential scanning calorimetry (TG/DSC), Nitrogen adsorption/desorption and Fourier transformed infrared spectroscopy (FTIR). The results showed that the production yield of CS increased from 2.1 to 32% with increasing the temperature from 160 to 180 °C, and the average size increased from 0.23 to 0.95 μm with extending the hydrothermal time from 8 to 16 h. pH value of the starting solution showed an evident effect on the morphology of CS via affecting the decomposition products of glucose. CS could be obtained when the pH value of starting solution was less than 12, but further increasing the pH value to 13–14 led to the formation of lumpy aggregations of carbon rather than spherical CS. The CS prepared under pH 6 and 9 showed good adsorption capacity for Methylene blue (MB), which was attributed to their relatively high specific surface area.     

Thermal nitridation synthesis of MN (M=Ti,V and Cr) nanocrystals from metals and NH4Cl

Nanocrystalline TiN, VN and CrN have been synthesized by a thermal nitridation reaction between the corresponding metal powder and NH₄Cl at 600 °C in an autoclave. X-ray powders diffraction (XRD) indicated that these nanocystallites had a NaCl-type structure with lattice parameters: a=4.236 Å for TiN, 4.133 Å for VN, 4.145 Å for CrN. Transmission electron microscopy (TEM) showed these products consisted of cubic nanocrystals. X-ray photoelectron spectroscopy (XPS) and thermogravimetric analysis (TGA) techniques revealed that all the products were almost pure nitrides.     

Microwave-assisted synthesis of cobalt oxalate nanorods and their thermal conversion to Co3O4 rods

Cobalt oxalate nanorods have been successfully synthesized by a simple microwave-assisted solution approach using an ionic liquid 1-n-butyl-3-methyl imidazolium tetrafluoroborate. Upon thermal decomposition at 400 °C, cobalt oxalate nanorods could be converted to Co₃O₄ rods consisting of nanoparticles. The products were characterized using X-ray powder diffraction, transmission electron microscopy, thermogravimetric analysis and differential scanning calorimetric analysis.     

Synthesis of ZnO nanosheets by room-temperature decomposition of a layered precursor synthesized by microwave heating

ZnO nanosheets with the wurtzite structure have been successfully synthesized via a microwave-assisted solution method. The thicknesses of ZnO nanosheets are in the range of 5–10 nm and lateral sizes up to 1 μm. The surfaces of ZnO nanosheets are planes of wurtzite structure. The as-prepared products were characterized by X-ray diffraction (XRD), transmission electron microscopy (TEM), high-resolution transmission electron microscopy (HRTEM). The optical and thermal properties were investigated with UV–Visible absorption spectra, thermogravimetric analysis (TG) and differential scanning calorimetric analysis (DSC).     

Controlled fabrication of noble metal nanoparticles loaded on the surfaces of cyclotriphosphazene-containing polymer nanotubes

We report on the fabrication of noble metal nanoparticles loaded on the surfaces of cross-linked poly(cyclotriphosphazene-co-4,4′-sulfonyldiphenol) (PZS) nanotubes of high stability. PZS nanotubes were first synthesized by precipitation polymerization between hexachlorocyclotriphosphazene and 4,4′-sulfonyldiphenol based on in situ template mechanism. Then the PZS nanotubes were directly used as scafford to load metal Au, Ag, and Pd nanoparticles, respectively, through cation complexation followed by gentle reduction. The structure and morphology of the metal/PZS nanocomposites were determined by means of Fourier transform infrared spectra, energy dispersive X-ray spectroscopy, elemental analysis, X-ray diffraction, scanning electron microscope, transmission electron microscope, and thermogravimetric analysis (TGA). Results showed that the metal/PZS nanocomposites possessed 460 °C of initial thermal decomposition temperature under air atmosphere and the loading amount of metal nanoparticles on the PZS nanotube surfaces could be controlled easily. As-fabricated metal/PZS nanocomposites are expected to have potential applications in catalysis.     

ZnS/TiO2聚砜纤维复合材料的制备及其光催化水制氢性能的研究

利用高压静电纺丝制备了具有良好耐光降解性能的羧基聚砜电纺纤维毡,利用其为载体用水热反应法制备了ZnS/TiO2聚砜复合光催化材料,得到了分布均匀的ZnS/TiO2聚砜纤维复合材料。通过X射线衍射、光电子能谱、紫外-可见漫反射光谱、热失重、耐紫外光降解实验对复合材料进行了表征。光催化分解水制氢实验表明:ZnS/TiO2含羧基聚砜纤维复合材料的催化效率高于同等条件下粉体ZnS/TiO2,并且具有很好的重复稳定性。     

Synthesis of nanoparticles of barium lanthanum hafnium oxide by a modified combustion process

Barium lanthanum hafnium oxide, a complex perovskite ceramic, has been synthesized as nanoparticles by a modified combustion process for the first time. The Ba, La, and Hf ions required for the formation of Ba2LaHfO5.5 were obtained in solution by dissolving in boiling nitric acid a stoichiometric mixture of BaCO3, La2O3, and HfO2 that had been heated at 1200 degrees C for 4 h. By complexing the ions with citric acid and using ammonia as fuel, it was possible to get Ba2LaHfO5.5 as nanoparticles in a single-step combustion process. The powder obtained by the present combustion process was characterized by X-ray diffraction, BET surface area analysis, differential thermal analysis, thermogravimetric analysis, infrared spectroscopy, and scanning and high-resolution transmission electron microscopy. According to the results of X-ray and electron diffraction, the powder synthesized through the combustion process showed single-phase barium lanthanum hafnium oxide. The transmission electron microscopic investigations showed a grain size of 42 nm, with a standard deviation of 8 nm. The nanoparticles of Ba2LaHfO5.5 synthesized by the present combustion technique could be sintered to > 97% of the theoretical density at a relatively low temperature of 1425 degrees C. Scanning electron microscopic studies on the sintered Ba2LaHfO5.5 samples showed that the final grain size of the sintered specimen was < 500 nm.     

Spectroscopic and thermal behavior of ZnHg(SCN)4

The synthesis and purification of zinc mercury thiocyanate, ZnHg(SCN)₄ (ZMTC), are described. The identity of the synthesized compound was characterized by elemental analysis, X-ray powder diffraction, infrared, Raman, and UV/Vis/NIR transmission spectra. The thermal stability and thermal decomposition of ZMTC crystal were investigated by means of thermogravimetric analysis (TGA) and differential scanning calorimetry (DSC) measurements. The intermediates and final products of the thermal decomposition were identified by X-ray powder diffraction (XRPD).     

Detailed characterization of hydrothermally synthesized SnO2 nanoparticles

3-4 nm of SnO2 nanoparticles having uniform spherical shape were successfully synthesized using a hydrothermal method. The hydrothermal method has many advantages over other methods of preparing nanoparticles (such as sol-gel, solid state, and chemical precipitation), because there is no need for calcination and milling steps. The particles were characterized by X-ray diffraction, pore size diamater analysis, transmission electron microscope, scanning electron microscope analysis, Raman spectroscopy, and thermogravimetric analysis/differential thermogravimetric analysis. The results confirm that SnO2 nano powders are homogeneous, nano scale, and of high crystalline quality.     

The use of novel biodegradable,optically active and nanostructured poly(amide-ester-imide) as a polymer matrix for preparation of modified ZnO based bionanocomposites

A novel biodegradable and nanostructured poly(amide-ester-imide) (PAEI) based on two different amino acids, was synthesized via direct polycondensation of biodegradable N,N′-bis[2-(methyl-3-(4-hydroxyphenyl)propanoate)]isophthaldiamide and N,N′-(pyromellitoyl)-bis-l-phenylalanine diacid. The resulting polymer was characterized by FT-IR, ¹H NMR, specific rotation, elemental analysis, thermogravimetric analysis (TGA), differential scanning calorimetry (DSC), X-ray diffraction (XRD) and field emission scanning electron microscopy (FE-SEM) analysis. The synthesized polymer showed good thermal stability with nano and sphere structure. Then PAEI/ZnO bionanocomposites (BNCs) were fabricated via interaction of pure PAEI and ZnO nanoparticles. The surface of ZnO was modified with two different silane coupling agents. PAEI/ZnO BNCs were studied and characterized by FT-IR, XRD, UV/vis, FE-SEM and TEM. The TEM and FE-SEM results indicated that the nanoparticles were dispersed homogeneously in PAEI matrix on nanoscale. Furthermore the effect of ZnO nanoparticle on the thermal stability of the polymer was investigated with TGA and DSC technique.