Preparation and characterization of gelatin/cerium(Ⅲ) film

A novel gelatin film with antibacterial activity was prepared by electrostatic crosslinking using cerium (Ⅲ) nitrate hexahydrate as the crosslinking agent. The structure and properties of the films were investigated by Fourier transform infrared spectra, tensile tests, thermogravimetric analysis, static drop contact angle and disc diffusion method. The results showed that cross-linking could not only improve the thermal and mechanical properties and lower the hydrophilic property of the films, but also make...     

Enhancing water repellence and mechanical properties of antibacterial gelatin/Ce(Ⅲ) fiber by heat treatment

The water repellence and mechanical properties of the gelatin/Ce(Ⅲ) fiber(GCe fiber) were improved by heat treatment,which was an easy and non-toxic method.The microscopic morphology,mechanical properties,antibacterial activity,and cell culture of the GCe fibers by heat treatment(HGCe fiber) were investigated.It was found that the water repellence and mechanical properties of the HGCe fibers increased significantly along with temperature increase.SEM observation showed that HGCe fibers had a fairly smooth surface and a compact structure.Detailed characterization revealed that the HGCe fibers exhibited similar antibacterial activity with the GCe fibers against Staphylococcus aureus.In addition,the results of cell culture by morphological assessment and methylthiazolyl tetrazolium assay(MTT assay) indicated the good biocompatibility of GCe fibers.Therefore,the HGCe fibers could be a promising candidate biomaterial for biomedicine applications.     

Active Nano Metal Oxide Coating for Bio-fouling Resistance

Titanium is known for excellent corrosion resistance for the sea water-cooled condenser material but susceptible to biofilm formation and bio-fouling, leading to deterioration in the heat transfer properties. Present study involves an attempt to use nanotechnology based surface modification of titanium to improve the antibacterial property and thereby resistance to biofouling. Synthesis of zinc oxide (ZnO) nano structures on Ti by a simple wet chemical method was achieved with the formation of nano structures under mild conditions in the absence of any seed, catalysts or surfactants. These nano structures were characterized using Field emission scanning electron microscopy which showed nano needle like structures. Grazing Incidence X-ray diffraction pattern showed a Wurtzite phase ZnO with strong peak at (002), indicating nano structure growth along the c-axis. Laser Raman Spectroscopy studies also confirmed the presence of Wurtzite crystals of ZnO nano structures. The antibacterial activity of these ZnO coatings with respect to gram negative bacteria, Pseudomonas aeruginosa sp. was investigated qualitatively and quantitatively. Epifluorescence microscopy and total viable count analysis have confirmed that ZnO nanostructures on the titanium substrate provided antibacterial activity against Pseudomonas aeruginosa.     

Complement activation by bacterial surface glycolipids: a study with planar bilayer membranes

Parameters affecting the characteristics of the drug loaded crosslinked sodium alginate matrix films and the release of metoclopramide hydrochloride and cisapride from these matrices were studied. It was shown that the release rate is influenced by the crosslinking technique of the matrix film, crosslinker type and concentration, drug physico-chemical properties especially solubility and the molecular weight, acidity of the release medium, concentration and the loaded quantity of the drug in the matrix. The crosslinking process of the matrix film was shown to be an interfacial phenomenon and the nature of crosslinking depends on the crosslinker type and concentration. This work also showed that crosslinked alginate in a matrix form has limitation in practical use due to the effect of acidic medium on the crosslinking of the matrix film and hence, the rate of drug release.     

Preparation of Nd-Fe-B Magnets by Screen Printing

Magnetic NdFeB thick films were prepared by screen printing a NdFeB-based ink. The films are isotropic and the thickness varied from 30 microns to 1 mm. The printing parameters were optimized with respect to the mechanical and the magnetic properties of the films. After curing at 390 K good adhesive non porous films were obtained. The magnetization of films are 400 emu/cc, the coercive field H_c is 1 Tesla, the B_r is 4 kG and the energy product is 2.7 MGOe (21.5 kJ/m^c). Rotors with those magnetic properties tested in stepper motors with promising efficiency.     

The Effect of Substrate Position during Cylindrical DC Magnetron Sputtering on Physical Properties of Fe7Co3 Thin Film

The high saturation induction makes Fe_1?x Co _x thin films desirable for use as recording head materials. In this experiment, Fe₇Co₃ thin films were deposited by DC cylindrical magnetron sputtering using the different position of glass substrate in argon pressure of 2 × 10^?2 Torr under sputtering power of 120 W. The magnetic properties were determined by scanning probe microscopy. The surface morphology and r.m.s roughness of thin films were analyzed using atomic force microscopy and the optical properties have been analyzed by spectrophotometer. The thin film thickness, grain size and optical properties were affected by changing substrate position and we found the deposition influenced magnetic properties and surface morphology.     

The epitaxial deposition of silicon on insulating substrates for MOS circuitry

Parasitic capacitances associated with large junction areas in bulk silicon MOS transistors can be virtually eliminated if MOS devices can be fabricated in silicon films on insulating substrates. The problem has been not only one of achieving suitable electrical properties in the thin films, but also of maintaining the “as-deposited” properties during the thermal treatments used in device processing. The changes in the electrical properties have made it particularly difficult to reproducibly fabricate deep depletion MOS devices, which require the deposition of thin films (less than 1.5μ) with carrier concentrations as low as ～5 × 10¹⁴ per cu cm. Modifications in the film deposition procedures and in the pregrowth treatment of the substrate have enhanced the thermal stability of the electrical properties sufficiently for the fabrication of deep depletion MOS devices on 1.0 μ thick films. Procedures have also been developed for the deposition of bothn-andp-type silicon on the same insulating substrate by a “two-stage” epitaxial process. Thus, both components of the complementary pair circuit may be enhancement mode devices. Since relatively high carrier concentrations can be employed in the discreten andp-type films, the doping requirements and the processing of the device structures have been considerably eased. The deposition conditions and the ability to deposit high quality silicon on a substrate surface from which silicon has been previously removed are interrelated and are important considerations in performing the two-stage epitaxial process.     

Hydrophilic and photocatalytic performances of lanthanum doped titanium dioxide thin films

Pure and La-doped TiO2 thin films were prepared on glass by sol-gel method using tetrabutyl titanate as Ti precursors. Their chemical composition, structure and properties were characterized by X-ray d...     

Nanocrystalline films of soft magnetic iron-based alloys

The physicochemical and structural aspects of designing soft magnetic alloys Fe-MX (where M is a Group III–V metal of the periodic table and X = C, N, O) in the form of nanocrystalline films precipitation-hardened by refractory interstitial phases are discussed and developed. The results of studying the structure and magnetic properties of Fe₇₈Zr₁₀N₁₂ films are reported. The films in the amorphous state are produced by reactive magnetron sputtering. Upon annealing at 300–600°C, the amorphous films crystallize to form mainly a bcc α-Fe-based phase and the fcc ZrN phase. The grain size of the bcc phase is shown to increase from ～3 nm to ～30 nm as the annealing temperature increases; the grain size of the fcc phase does not exceed 2–3 nm. Films annealed at 400°C exhibit a record level of magnetic properties: H _c = 5–6 A/m and B _s = 1.7–1.8 T. The experimental results obtained confirm the validity of our scientific approach.     

Dual-functionalization based on combination of quercetin compound and rare earth nanoparticle

While the nanoparticles like La2O3 and other rare earth oxides were believed to be able to provide effective scavenging hydroxyl radical.Quercetin,a hydrophobic agent,showed some potential antibacterial activity.The present work successfully performed the surface modification of rare earth nanoparticle using facile and general strategy.In specific,the hydrophobic quercetin was grafted on the rare earth nanoparticle through the coupling with silane.The surface modified nanoparticle was characterized by Fourier-transform infrared(FTIR),thermogravimetric analysis(TGA),and scanning electron microscopy(SEM).The surface modification helped to retain both the scavenging hydroxyl radical property of rare earth nanoparticle and the antibacterial activity of quercetin.This dual-function properties showed potential for application in the development of biomedicine such as antioxidant,anti-inflammatory,antibacterial and anticancer.     

Effect of Ti cap layer thickness on microstructures and magnetic properties of Ti/Ni/Ti films

Nanogranular Ti (3 nm)/Ni(30 nm)/Ti(t nm) (t=1, 3, 5, 7, 10) films were prepared by facing magnetron sputtering from Ti and Ni onto glass substrates at room temperature. The structural and magnetic properties of films strongly depended on the Ti layer thickness. X-ray diffraction (XRD) patterns of all as-deposited films showed strong FCC Ni(111) peak. Vibrating sample magnetometer (VSM) measurements indicated that the perpendicular coercivity of the Ti (3 nm)/Ni (30 nm)/Ti (3 nm) film reached about 36 kA/m. With the increase of Co layer thickness, coercivity (H_c) first increased and then decreased. The grain size and magnetic clusters slightly increased and the value of roughness (R_a) was smallest at t=3 nm.     

Magnetic properties of SmCo-based permanent magnetic films during 25 to 300 ℃

Magnetic properties of the SmCo-based permanent magnetic films prepared on hot substrate with Mo and Cr underlayer without subsequent annealing process were investigated by vibrating sample magnetometer （VSM）, X-ray diffraction （XRD）, and en- ergy dispersive X-ray spectroscopy （EDS）. The results showed that the film thickness of the SmCo-based films presented complex effect on the intrinsic coercivity Hci. Optimal Hc~ for the films with Mo underlayer, Cr underlayer, and without underlayer was ob- served with different film thicknesses. Furthermore, the monotonous temperature dependence of Hci was found to be strongly corre- lated with the magnetic parameters for the 3.0 μm thick SmCo7 films with Mo underlayer. From 25 to 300 ℃, the Hci decreased from 281.6 to 211.2 kA/m with a temperature coefficient of-0.091%/℃, exhibiting good temperature stability.     

Effect of magnetron sputtering conditions on the structure and magnetic properties of FeZrN films

Nanocrystalline Fe_{97 ? x} Zr₃N _x films produced by rf reactive magnetron sputtering onto rotating and stationary substrates are studied. X-ray diffraction analysis is used to study the structure of the as-sputtered and annealed (at 300–600°C) films. The maximum saturation induction B _s reached for the films under study is 1.8–1.9 T; the minimum coercive force H _c is 1.5–1.8 Oe. These magnetic properties are explained using the structural state of the films.     

Cerium ions crosslinked sodium alginate-carboxymethyl chitosan spheres with antibacterial activity for wound healing

For wound healing,wound infection caused by bacteria is one of the important reasons that delay wound healing process.Therefore,it is very meaningful to develop a multifunctional wound dressing with antibacterial capability to accelerate wound healing.Sodium alginate(SA) and carboxymethyl chitosan(CMCS) are the most commonly used compositions in wound dressing,but their poor stability inhibits the further applications.Introducing CMCS and using cerium ions(Ce³⁺) to crosslink CMCS and ...     

两步机械球磨法制备M/TiO2复合薄膜及光催化性能研究

采用两步机械球磨法制备了M/TiO₂（M = Al、Sn、Zn、Ti）双层复合薄膜,利用光学显微镜和X射线衍射仪分析了涂层的微观结构和相组成,测定了薄膜的光催化性能,研究了过渡层材质以及球磨时间对复合薄膜光催化性能的影响。研究表明,TiO₂粉体在球磨过程中的晶体结构未发生显著变化,保持了良好的光催化活性。金属过渡层Al、Sn以及Zn将显著削弱复合薄膜的光催化活性,Ti是复合薄膜的理想金属过渡层,制备的Ti/TiO₂复合薄膜具有优异的光催化性能。随着第二步球磨时间的延长,Ti/TiO₂复合薄膜的光催化性能逐渐降低,这是由于第二层薄膜表面TiO₂含量降低的原因所致。     

Nucleation and epitaxy growth of high-entropy REBa2Cu3O7-δ(RE=Y,Dy,Gd,Sm,Eu)thin films by metal organic deposition

High-entropy REBa₂Cu₃O_7-δ(RE=Y_0.7+Dy_0.2+Gd_0.2+Sm_0.2+Eu_0.2)(HE-REBCO) superconducting films doped with multiple rare earth elements were successfully fabricated with thickness up to 800 nm by a trifluoroacetate-metal organic deposition(TFA-MOD).The enhanced entropy change ΔS of the HEREBCO system promotes the c-axis growth of REBCO thin film in the competition with a/b-axis growth.The microstructure and elemen...     

La3＋-doped SrBi2Ta209 thin films for FRAM synthesized by sol-gel method

This paper discusses the possibility of synthesis of SBTL sol-gel films for use as active layers for non-volatile memory （FRAM）. La-doped SrBi2Ta209 thin films were synthesized by sol-gel method on Pt/TiO2/BPSG/SiO2/Si substrates. The structural features of the surface （AFM）, crystallization behavior （XRD） during the heating and ferroelectric properties of synthesized films were discussed. It was shown that an optimum surface structure and a high share of perovskite phase of SBTL-films were compared to SBT-films （Theating=800 ℃）. Achieved ferroelectric parameters suggested the possibility of using synthesized SBTL sol-gel films in non-volatile memory devices.     

Effect of hot work on the properties of Waspaloy

The effects of process history on the properties and microstructure of wrought Waspaloy have been investigated. Forge practice is shown to be critical if the forging temperature exceeds theγ′ solution temperature. A light reduction at high temperatures decreases fracture ductility as evaluated by impact, tensile and rupture tests. The most significant microstructural feature is the formation of MC carbide boundary films.     

Fabrication of low-resistance LaNi_xO_(3+δ) thin films for ferroelectric device electrodes

LaNiO_3 thin films with different La/Ni ratios were deposited on Si substrates by sol-gel process. The electrical resistivities of LaNi_xO_(3+δ) films with different La/Ni ratios were measured by four-probe method.LaNi_(0.95)O_(3+δ) thin film has the lowest resistivity. First-principle calculations show that LaNi_(0.95)O_(3+δ) has the largest Ni-O-Ni bond angle and the shortest Ni-O bond length, which means LaNi_(0.95)O_(3+δ) has the strongest metallic property, hence, the electrical resistivity is the lowest. Au/PZT(PbZr_(0.52)Ti_(0.48)O_3)/LaNi_xO_(3+δ) and Au/PZT/Pt ferroelectric capacitors were fabricated to evaluate LaNi_xO_(3+δ) as a bottom electrode. It is shown that fatigue properties of PZT films can be significantly improved by using LaNi_xO_(3+δ) instead of Pt as the bottom electrode. The Ⅰ-Ⅴ test results of PZT films show that LaNi_(0.95)O_(3+δ) as bottom electrode can reduce the threshold voltages of PZT films, suggesting that La/Ni ratio in LaNi_xO_(3+δ)has a large influence on the film properties.     

Synthesis, characterization and properties of some rare earth complexes with 2,6-pyridine dicarboxylic acid and α-Picolinic acid

Five novel ternary complexes were synthesized by the rare earth with 2,6-pyridine dicarboxylic acid andα-picolinic acid.These complexes were characterized by elemental analysis,molar conductivity,FT-IR,UV-Vis,Raman,TG-DTA and XRD.The general formula of the complexes was[RE(DPA)(L α )(H2O)]·2H2O(RE=Pr 3+ ,Nd 3+ ,Sm 3+ ,Eu,Er 3+ ;DPA=2,6-pyridine dicarboxylic acid;L α =α-picolinic acid). The investigation of fluorescence properties of the Eu-complex showed that the Eu(III)ion could be sensitized efficiently by the ligand to some extent.The antibacterial activity test indicated that all the five complexes exhibited antibacterial ability against Escherichia coli and Staphylococcus aureus with broad antimicrobial spectrums.