低辐射隔热复合镀膜玻璃的制备

采用溶胶-凝胶法成功制备了SnO2∶F/SiO2气凝胶复合镀膜玻璃,并采用扫描电子显微镜(SEM)、导热系数仪、红外光谱仪,紫外-可见光谱仪等对镀膜玻璃的微观结构、热导率、辐射率、透光率等进行了表征。结果表明,镀膜玻璃的透过率最高在75%左右;辐射率为0.53,复合镀膜玻璃与FTO玻璃相比,其热导率从3.615W/(m·K)降低到3.368W/(m·K),所得复合镀膜玻璃兼具低热导性和低辐射性。     

Study of the adhesion of Staphylococcus aureus to coated glass substrates

The adhesion of Staphylococcus aureus was studied using a selection of laboratory-prepared and commercially available coated glass substrates using a simple methodology. Substrates were examined by scanning electron microscopy, atomic force microscopy and water droplet contact angles. It was found that microbial adhesion was independent of surface roughness, when this was of a lower magnitude than microbial size. It was also found that microbial adhesion was greater for hydrophilic surfaces than for hydrophobic ones, but that on a photoinduced superhydrophilic surface, microbes were more spread out—a potential benefit for more effective photocatalytic disinfection. It is suggested that hydrophobic and photoinduced superhydrophilic surface coatings both have potential as a means of reducing microbial fouling of surfaces.     

Surface properties and adhesion of maleinized polyethylene films

The wettability and the adhesion of polyethylene films were improved by introducing polar groups in the polymer chains. The surface properties of films grafted with maleic anhydride (MA) were investigated. The wettability was found to be dependent on the MA content, on the film preparation conditions and on the hydrolytic process of the anhydride groups. The kinetics of the hydrolysis indicated a restructuring of the polymeric surface due to the movement of the polar groups towards the surface; it did not influence the adhesion properties. The behaviour of the maleinized films was compared with oxygen plasma treated materials, which showed a better wettability, but a worse adhesion on polar substrates than the maleinized polyethylene. These results were explained on the basis of X-ray photoelectron spectroscopic analyses, by which the main functional groups present at the surface were identified and quantitatively determined. © 1998 Chapman & Hall     

Surface properties and adhesion mechanisms of graft polypropylenes

Improvement of the adhesion capacity of polypropylene to aluminium can be obtained by adding a small quantity of maleic anhydride grafted polypropylene to the polymer. With increasing maleic anhydride content, the peel strength of the polymer-aluminium assembly first increases due to migration, orientation and chemical bonding, and then decreases as a result of the formation of a weak boundary layer, made of the low molecular weight grafted polymer chains. This study stresses the importance of two phenomena in adhesion: the restructuring of the polymer at the metal interface and the formation of an interphase.     

Mechanical properties of biodegradable polymer sutures coated with bioactive glass

Combining commercially available Polyglactin 910 (Vicryl®) sutures with bioactive glass powder offers new possibilities for application of composite materials in tissue engineering. Commercial bioactive glass (45S5 Bioglass®) powder was used to coat Vicryl® sutures and the tensile strength of the sutures was tested before and after immersion in simulated body fluid (SBF) as a means to assess the effect of the bioactive glass coating on suture degradation. Different gauge lengths (126.6 and 111.6 mm) and strain rates (2.54, 11.4 and 25.4 mm/min) were tested. The tensile strength of composite sutures was slightly lower than that of as-received Vicryl® sutures (404 MPa versus 463 MPa). However after 28 days immersion in SBF the residual tensile strength of the coated sutures was significantly higher, indicating a protective function of the Bioglass® coating. The tensile strength results were similar for the different gauge lengths and strain rates investigated. A qualitative explanation for the effect of bioactive glass coating on polymer degradation is offered.     

彩色双层复合镀膜玻璃的在线制备与性能

分别采用电化学方法和化学气相沉积法对生产线锡槽和退火窑内的浮法玻璃两次镀膜,制备出具有阳光控制功能的双层彩色浮法玻璃,采用分光光度计、扫描电镜、能谱仪、透射电镜、原子力显微镜和二次离子质谱等方法分析了复合镀膜样品的形貌．结构,研究了不同深度的膜层成分和性能．结果表明,可见光透射比与硅烷浓度和电流强度之间有强烈依赖性;上层的硅膜表面均匀平整,表面粗糙度约9．66nm,团粒尺寸约100nm,其厚度约70-78nm,且沿厚度方向呈梯度化氧化;底层膜中铜和铋的扩散深度约10μm．     

Titanium deposition onto ion-bombarded and plasma-treated polydimethylsiloxane: Surface modification,interface and adhesion

Titanium films were deposited by electron beam evaporation onto polydimethylsiloxane (PDMS) substrates. Ar⁺ bombardment as well as O₂ plasma pretreatments were found to enhance the adhesion of the titanium films markedly. X-ray photoelectron spectroscopy and scanning electron microscopy were used to study the influence of the pretreatments on the PDMS surface morphology. Both pretreatments resulted in cross-linking and thereby an increased strength of the substrate surface. X-ray photoelectron spectroscopy was also used, together with in situ electron beam evaporation, to study the initial titanium film growth on as-prepared and Ar⁺-bombarded samples. The C 1s and O 1s peak shifts showed an enhanced film-substrate interaction attributed to formation of Ti-C and Ti-O bonds respectively. The film-substrate interaction was also observed as a change in the titanium film growth mode. If the samples were ion bombarded prior to deposition the film growth changed from a pronounced three-dimensional growth towards a more two-dimensional growth mode.     

镀有非对称交替膜系的玻璃颜色特性研究

本文对镀有非对称折射率高低交替膜系的玻璃的颜色特性进行了研究。比较了不同的膜系结构形式,通过改变每层膜的厚度,可得到的不同的色品坐标。发现镀的玻璃上的第一层膜为高折射率材料所得到的玻面颜色好。灾个结论可应用到玻璃装饰业上。     

Intact endothelial cell sheet harvesting from thermoresponsive surfaces coated with cell adhesion promoters.

Recently, with the development of smart polymers, research has looked to using thermoresponsive polymers as cell culture substrates. These novel surfaces allow the cultivation of cells without enzymes using the thermoresponsive phase transition property of poly(N-isopropylacrylamide) (PNIPAAm). However, this requires expensive techniques to generate a sufficiently thin film that allows cell adhesion. In this study, we looked at simple solvent cast films which normally show poor cell adhesion, but here the films are coated with cell adhesion promoters (CAPs) to improve cell growth without altering the copolymer thermoresponsive behaviour.A copolymer of PNIPAAm and N-tert-butylacrylamide (NtBAm) with a ratio of 85:15, respectively, was synthesized and solvent cast. The copolymer films were coated with CAPs, such as collagen, fibronectin and laminin, to increase their cell adhesion and growth properties. Cell activity measured by the alamarBlue assay showed similar results for coated copolymer films and standard tissue culture plastic controls. Deposition of CAPs on to the copolymer films was characterized by scanning electron microscopy and atomic force microscopy. Cell detachment from the copolymer films is not affected by the surface coatings of CAPs, and endothelial cells are recovered as an intact sheet, which has great potential for uses in tissue engineering applications. The results demonstrate a versatile method for the cultivation of cells while eliminating the need for the use of digestive enzymes such as trypsin. This study shows that cultivation on physically bonded PNIPAAm copolymers is viable and achievable by relatively simple methods.     

环保型耐高温涂层织物的制备与性能研究

为制备受热熔融或分解后放出毒害气体低于致毒量的高性能热防护织物,通过在苯甲基有机硅树脂溶液中添加多种填料,利用改性的复合有机硅树脂溶液制备了玻璃纤维涂层织物.探讨了填料粒径及偶联剂等对涂层液存贮稳定性的影响,并对涂层织物的热防护性能和物理性能进行测试.结果表明:涂层后织物的烧蚀隔热性能显著提高,涂层织物为不燃材料;在不超过600℃受热30 min,其性能稳定;遇热释放的烟气中仅有少量的CO和NO_x,其含量远远低于制毒量;涂层后织物具有良好的强力、拒水、拒油及抗静电性能.该涂层织物在产业用和建筑领域将具有广阔的应用前景.     

Jute fibre/epoxy composites: Surface properties and interfacial adhesion

Jute fibres were surface treated in order to enhance the interfacial interaction between jute natural fibres and an epoxy matrix. The fibres are exposed to alkali treatment in combination with organosilane coupling agents and aqueous epoxy dispersions. The surface topography and surface energy influenced by the treatments were characterized. Single fibre pull-out tests combined with SEM and AFM characterization of the fracture surfaces were used to identify the interfacial strengths and to reveal the mechanisms of failure.     

涂铁多孔陶瓷吸附去除亚甲基蓝的热动力学

研究了涂铁多孔陶瓷(IOCPC)在20～40℃下对亚甲基蓝(MB)静态吸附的热动力学性质.用液相沉积、多次涂层法对赤泥质多孔陶瓷表面改性制备吸附剂,并通过小试摇床实验考察了IOCPC在不同条件下吸附MB的效果.结果表明:IOCPC的比表面积为4.987m2/g,比改性前增大3.28倍,平均孔径为11.36nm.IOCPC对MB的吸附等温线呈S型,Freundlich等温吸附方程和准二级动力学方程较好地描述了IOCPC对MB的吸附等温线及吸附动力学实验结果,相关系数分别＞0.89和0.97,平衡吸附容量随温度的升高而增加.由标准吉布斯自由能变(莫獹＜0 )、标准反应焓变(莫獺0＞0)和吸附活化能(Ea=16.145kJ/mol＞4.184kJ/mol)的值可判断,IOCPC对MB的吸附是自发的、吸热的化学吸附反应.     

Bacterial adhesion to bisphosphonate coated hydroxyapatite

Staphylococcus aureus (S. aureus) is commonly associated with microbial infection of orthopaedic implants. Such infections often lead to osteomyelitis, which may result in failure of the implant due to localised bone destruction. Bacterial adhesion and subsequent colonisation of the device may occur as a consequence of contamination during surgery, or by seeding from a distant site through the blood circulation. Coating of the hydroxyapatite (HA) ceramic component of artificial hip joints with the bisphosphonates clodronate (C) and pamidronate (P) has been proposed as a means to minimise osteolysis and thereby prevent loosening of the implant. However, the effect of the bisphosphonate coating on bacterial adhesion to the HA materials must be determined before this approach can be implemented. In this study coated HA materials were incubated with the S. aureus and the number of adherent bacteria determined using the Modified Vortex Device (MVD) method. The number of bacteria adherent to the P coated HA material was significantly greater than that adherent to uncoated HA (60-fold increase) or to the C coated HA (90-fold increase). Therefore, even though earlier studies suggested that P bound to HA may improve osseointegration, the results presented would suggest that the use of this coating may be limited by the potential increased susceptibility of the coated device to infection.     

Electrical and optical properties of PLZT thin films on ITO coated glass by sol-gel processing

Sol-gel processed PLZT thin films were fabricated on ITO-coated glass substrates with RTA (rapid thermal annealing). The electrical and optical properties such as hysteresis curves, dielectric constant, dielectric loss and optical transmittance of thin films were investigated. The PLZT thin films were crystallized to the perovskite structure by RTA at 750°C for 5 min. As the La percentage was increased, the dielectric constant increased, and that of 9/65/35 PLZT thin film was 1750. The coercive field and remnant polarization decreased with La increase from 33.82 kV/cm to 14.71 kV/cm and from 39.26 C/cm² to 9.57 C/cm² respectively. As the Zr percentage increased at 2% La, the coercive field decreased from 52.94 kV/cm to 30 kV/cm, but the remnant polarization increased from 22.74 C/cm² to 50.75 C/cm², and the dielectric constant had a maximum value of 1269 at 2/55/45 composition. The optical transmittance was increased as La percentage increased but was decreased as the annealing temperature increased.     

Wavelength conversion film with glass coated Eu chelate for enhanced silicon-photovoltaic cell performance

In order to improve the conversion efficiency of a silicon-photovoltaic (PV) module, we investigated the combination with a wavelength conversion film (WCF), which consists of Eu chelate particles encapsulated by the sol–gel derived silica glass. The photoluminescence (PL) excitation spectrum of Eu chelate shows that the violet light below 400 nm is effectively converted to the red emission at 613 nm. Since the PV cell has higher sensitivity at the red wavelength region compared to the violet region, Eu chelate is one of the suitable material for a WCF. The diameter of fabricated sol–gel encapsulated Eu chelate was larger than the wavelength of irradiated sunlight, therefore, the transmittance of a WCF decreased with increasing the concentration of Eu chelate. The short circuit current (J_SC) was increased by inserting the the WCF on the front side of Si-PV cell compared to the reference module (glass/ethylene vinyl acetate/WCF without Eu chelate/Si-PV cell/EVA/back-film), and the maximum increase of ΔJ_SC was 1.03 mA/cm² compared to the reference module. However, the maximum ΔJ_SC of fabricated module was almost same as the conventional Si-PV cell due to the refractive index mismatch of each layers.     

Biomimetic hydroxyapatite coating on glass coverslips for the assay of osteoclast activity in vitro

The osteoclast (OC) is the cell type responsible for the resorption of bone. The activity of this cell is important in the aetiology of a large number of skeletal pathologies, and also for the biocompatibility and osseointegration of orthopaedic implant materials. OC mediated acid hydrolysis of calcium phosphate from the bone matrix offers a prime means of studying the biology and activity of this cell type. We have developed a method of coating glass coverslips with a hydroxyapatite (HA)-like mineral, using a biomimetic approach. Hydroxylation followed by formation of a self assembled monolayer (SAM) using the surfactant triethoxysilylpropyl succinic anhydride (TESPSA), allowed biomimetic deposition of HA-like mineral from a simulated body fluid (SBF). The biocompatibility of the TESPSA SAM-HA coated glass coverslips was tested by culturing human mature OC present in samples of giant cell tumour of bone (GCT). Parameters of OC activity were assayed, including F-actin ring formation, release of calcium and formation of osteoclastic resorption pits, confirming that OC were able to attach to and resorb the coated surface. This approach for the preparation of HA coatings on glass coverslips could have wide applicability for the study of osteoclast behaviour in vitro. Gerald J. Atkins and Peter Majewski share senior author status.     

Surface silver-doping of biocompatible glass to induce antibacterial properties. Part I: massive glass

A glass belonging to the system SiO₂–Al₂O₃–CaO–Na₂O has been subjected to a patented ion-exchange treatment to induce surface antibacterial activity by doping with silver ions. Doped samples have been characterized by means of X-Ray diffraction (XRD), scanning electron microscopy (SEM) observation, energy dispersion spectrometry (EDS) analysis, in vitro bioactivity test, Ag⁺ leaching test by graphite furnace atomic absorption spectroscopy (GFAAS) analyses, cytotoxicity tests by fibroblasts adhesion and proliferation, adsorption of IgA and IgG on to the material to evaluate its inflammatory property and antibacterial tests (cultures with Staphylococcus aureus and Escherichia coli). In vitro tests results demonstrated that the modified glass maintains the same biocompatibility of the untreated one and, moreover, it acquires an antimicrobial action against tested bacteria. This method can be selected to realize glass or glass-ceramic bone substitutes as well as coatings on bio-inert devices, providing safety against bacterial colonization thus reducing the risks of infections nearby the implant site. The present work is the carrying on of a previous research activity, concerning the application of an ion-exchange treatment on glasses belonging to the ternary system SiO₂–CaO–Na₂O. On the basis of previous results the glass composition was refined and the ion-exchange process was adapted to it, in order to tune the final material properties. The addition of Al₂O₃ to the original glass system and the optimization of the ion-exchange conditions allowed a better control of the treatment, leading to an antibacterial material, without affecting both bioactivity and biocompatibility.     

空心玻璃微球表面接枝聚苯乙烯及其性能研究

空心玻璃微球表面改性有利于改善其与基体间的相容性,提高复合泡沫性能.通过接枝聚苯乙烯对空心玻璃微球进行表面处理,采用SEM、IR、热失重等方法分析了反应条件对接枝的影响.结果表明,接枝反应过程中提高反应温度、延长反应时间有利于接枝率的提高,但温度过高会加速单体自聚,降低接枝率.接枝处理后,随着聚合物层的增厚,空心玻璃微球表面缺陷减小,破损率降低,抗压强度得到一定程度提高.     

Characterization of nanocrystalline Ni–Cu thin films electrodeposited onto ITO coated glass substrates: effect of pretreatment current density

In this work, Ni–Cu films were grown onto indium tin oxide coated glass substrates without and with galvanostatic pretreatment process at different current densities. In all cases, Ni–Cu films were electrodeposited at a constant deposition potential of ?1,800 mV versus saturated calomel electrode. After that, the surface morphology and structural properties of electrodeposited Ni–Cu films in dependence of pretreatment current density were studied. X-ray diffraction analysis showed that all films have face-centered cubic structure and consist of segregated two Ni-rich and Cu-rich phases regardless of pretreatment current density. The compositional analysis carried out by energy dispersive X-ray spectroscopy revealed that all films contain almost 90 wt% Ni and 10 wt% Cu. The average crystallite size decreased with decreasing pretreatment current density towards more negative values without inducing significant changes in the composition of the films. It was found that the preferred orientation of all films is in the [111] direction regardless of pretreatment current density. The effect of galvanostatic pretreatment process on the surface morphology investigated using a scanning electron microscopy and an atomic force microcopy were also discussed by means of obtained results.