Polystyrene film-coated glassware: a new means of reducing metal losses in trace metal speciation

A recently developed process for coating a glass surface with polystyrene (PS) film, by use of a simple chemical process has been used to reduce trace metal adsorption by cell components. The glass coating is a two-step procedure consisting of covalent attachment of vinyl-terminated PS to Si atoms on the glass surface then adsorption of PS from solution to create a stable PS film. To assess the quality of the coating we used anodic stripping voltammetry to study the adsorption of lead and cadmium ions in coated and untreated glass cells. In both short and long-term (24 h) experiments we observed that the amount of metal adsorbed was considerably less for the PS film-coated glass cell than for the uncoated cell. Further experiments showed that metal desorption is faster and metal contamination after cleaning is significantly lower for the coated cells. The PS film was, moreover, stable over a period of 6 months within the pH range 3.5–9.     

纳米陶瓷颗粒的电催化效应及其在复合刷镀层中的化学状态

采用循环伏安法和电位阶跃法研究了nano-Al₂O₃ / Ni复合电刷镀体系的电化学响应，探讨了纳米颗粒对复合电沉积的影响；用X射线光电子谱研究了复合镀层中nano-Al₂O₃颗粒与基质金属之间的相互作用。结果表明纳米颗粒能使金属沉积过电位显著降低，电流效率、金属成核率及晶体生长速度增加，从而对金属镍的电结晶表现出明显的催化效应；在金属镍电结晶过程中，部分到达阴极附近的nano-Al₂O₃颗粒被电极表面捕获。金属生长面上的吸附态镍原子到达纳米颗粒与电极表面接触处，与该处纳米颗粒表面的不饱和氧原子形成Ni-O化学键，纳米颗粒与基质镍以化学键形式结合。纳米颗粒与电极表面的结合区域成为新的成核或生长中心，在随后的刷镀过程中纳米颗粒逐渐被电沉积的金属镍包埋，从而形成复合镀层。     

Electrochemical corrosion behaviors and corrosion protection properties of Ni–Co alloy coating prepared on sintered NdFeB permanent magnet

In this study, a protective Ni–Co alloy coating was prepared on sintered NdFeB magnet applying electrodeposition technique. A pure nickel coating was also studied for a comparison. The microstructure, surface morphologies, and chemical composition of coatings were investigated using X-ray diffraction, scanning electron microscope, and energy dispersive spectroscopy, respectively. The corrosion protection properties of coatings for NdFeB magnet in neutral 3.5 wt.% NaCl solutions were evaluated by potentiodynamic polarization and electrochemical impedance spectroscopy (EIS) techniques. The microstructure and surface morphologies analysis showed that the addition of cobalt element into matrix metal Ni altered the preferential orientation of pure nickel coating from (2 0 0) crystal face for pure nickel coating to (1 1 1) crystal face for Ni–Co alloy coating, and made the surface morphologies more compact and uniform due to the grain-refining. The results of potentiodynamic polarization test showed that compared with pure nickel coating, Ni–Co alloy coating exhibited much nobler corrosion potential (E _corr) and lower corrosion current density (j _corr), indicating better anticorrosive properties. The long-term immersion test by dint of EIS indicated that the Ni–Co alloy coating still presented high impedance value of 1.9 × 10⁵ Ω cm² with the immersion time of 576 h indicating the excellent anticorrosive properties, and corrosion protection properties of nickel coating for NdFeB magnet practically disappeared with the immersion time of 144 h, which also indicated that the Ni–Co alloy coating provided better corrosion protection properties for the NdFeB magnet compared with nickel coating.     

Inhibition of Pb-Leaching from Lead Crystal Glass by Coating with Films Prepared by the Sol-Gel Method

The chemical durability of lead glass tumblers (24% PbO) in a 4% (v/v) acetic acid solution before and after coating with sol-gel derived SiO2 films was assessed to determine the extent of reduction in Pb-leaching that can be achieved. It was found that by coating the internal surface of the glass tumblers with 1 ml of 10% TEOS solutions at 100°C and densifying the coating formed at 500°C for 1 h, it was possible to reduce Pb-leaching to about one quarter of that of the uncoated glass.     

低温低内应力化学镀镍工艺的研究

化学镀广泛应用于非金属的电镀、电铸前的施加导电层。化学镀沉积层质量与其在零件上的附着力有着密切的关系 ,重视对化学镀沉积层内应力的研究 ,开发一个低温、低内应力的化学镀镍工艺 ,对于化学镀沉积层的推广应用有着十分重要的意义。本文采用正交实验方法对低温、低内应力化学镀镍工艺进行了系统研究 ,开发出了一个低温、低内应力的化学镀镍工艺。在实验过程中发现沉积层内应力同其在零件上的结合力具有密切关系并对其进行了初步探讨。1　实验方法1 1　正交实验根据探索性实验结果分析 ,影响化学镀镍层内应力σ和沉积层速率ｒ的主要因…     

Atomic force microscopy of coated glasses

Atomic force microscopy has been used to investigate the topology of alkoxide gel dip coatings on different substrates. Results of SiO(2) - TiO(2) - ZrO(2) (STZ) coatings are presented on float glass, on polished fused silica, on commercially coated insulating flat glass, and on PtRh. Consolidated STZ coatings display the so-called glass pattern with ripples equal or less than 2 nm high. The same pattern is seen on partially dense STZ coatings, as soon as the surface is stiff enough for scanning, and also on the bottom of a 50 nm deep sputtering crater in the consolidated coating. The vitreous STZ coating on the fire side of the float glass is as flat as the float glass itself. It has the same tendency to contamination. 100 nm wide and 50 nm deep polishing grooves on fused silica have been filled up with the 80 nm thick coating, only dips of a few nm remain. The trenches between the SnO(2) crystallites on the insulating flat glass were filled up and the roughness of the substrate was partially reduced. PtRh sheet remained rough even after the coating. On the partially densified STZ coating, sputtering generates a grained surface.     

Application of Microbeam Techniques to Materials Problemsin a Service Laboratory

 Examples for providing analytical services with microbeam techniques are elucidated in the areas of failure analysis, chemical thin film analysis in glass coating, manufacture control of optical coatings, characterization of microelectronic devices and tribostressed surfaces in diesel motors of passenger cars. Besides the specific analytic or material problems and the techniques and methods used the characteristic aspects of surface and thin film analysis within the scope of analytical services are emphasized.     

Internal modification of poly(dimethylsiloxane) microchannels with a borosilicate glass coating

We report on an original technique for the in situ coating of poly(dimethylsiloxane) (PDMS) microchannels with borosilicate glass, starting from an active nonaqueous and alkali-free precursor solution. By chemical reaction of this active solution inside the microchannel and subsequent thermal annealing, a protective and chemically inert glass borosilicate coating is bonded to the PDMS. Attenuated total reflectance Fourier transform infrared (ATR-FTIR) spectroscopy and nuclear magnetic resonance spectroscopy of the active solution show that it is composed of a silicon oxide network with boron connectivity. Thermal gravimetric analysis demonstrates the absence of organic content when curing is done above 150 degrees C. The borosilicate nature of the glass coating covalently bonded to the PDMS is demonstrated using ATR-FTIR spectroscopy and X-ray photoelectron spectroscopy. Atomic force microscopy and scanning electron microscopy show a smooth and crack-free coating. The latter is used as an efficient protective barrier against diffusion in PDMS of fluorescent rhodamine B dye that is dissolved either in water or in toluene. Moreover, the coating prevents swelling and consequent structural damage of the PDMS when the latter is exposed to harsh chemicals such as toluene.     

Deposition of protective-decorative coatings onto aluminum alloys

Technique for deposition of a nickel coating onto various aluminum alloys was developed. This coating can be used both independently and as a sublayer under multilayer coatings and, in particular, under those of nickel, tin–bismuth, lustrous nickel, and lustrous chromium. The technique includes anodization, chemical treatment, and electrodeposition of nickel in a special solution. The working modes of the anodization electrolyte were chosen and the necessity for a preliminary chemical treatment of the oxide film being formed was substantiated. A composition of the acid electrolyte for the subsequent nickel plating was developed with buffer and improving additives. The thus deposited electroplated nickel coatings exhibit a high adhesion to the aluminum base without additional thermal treatment. This makes it possible not only to reduce the technological time for deposition of the subsequent multilayer coatings, but also to fully automate the whole process.     

Vacuum coating of plastic optics

Vacuum technologies for the deposition of optical interference coatings on polymer substrates, based on long-term experience in glass coating, have been under development for about 20 years. A growing market for precision optical elements and consumer optics moulded from thermoplastic polymers requires antireflective properties and hard coatings. Owing to the manifold chemical and physical properties of optical polymers, special efforts are essential for each type of plastic to find polymer-capable coating conditions. The main focus of this article is on evaluating the state of the art in vacuum-coating processes applied to plastics today, and on discussing specific coating techniques and evaluation procedures. A better understanding of the complex interactions between low-pressure plasmas and the various polymer materials will be a key factor in making durable plastic optics for future applications; achieving this will be a challenge to surface scientists.     

Hardness Equation for Ormosils

Hardness of ormosils coating on various kinds of substrates is important, and by considering recent progresses in understanding the hardness of ionic crystals or covalent crystals, new hardness equations for calculating the hardness of glasses or ormosils from chemical compositions were derived. When we applied an indenter to the surface of glass or sol-gel coatings, the surface of indenter is a declined one to the flat surface of glass or coating, thus the applied force should be analyzed by using the shear modulus, S, and Young's modulus, E. This is now well accepted for the analysis of hardness of ionic or covalent bonding inorganic materials. For example, by considering the binding energy and plastic deformation, Gilman showed that Hv of NaCl crystal can be calculated by an equation including elastic stiffness which indicated a good agreement between calculated and observed value. For covalent crystals he reported that the strength of chemical bonds could be correlated with the glide (shear) activation energy for covalent crystals quantitatively. These explanations are basically applied to the hardness of silicate glasses and ormosils. By considering both shear modulus and Young's modulus we have derived equations for calculating the hardness of glasses or ormosils from chemical composition, which includes packing density of atoms and bond energy per unit volume has been taken account. The agreements between calculated and observed hardness values for ormosils were comparatively good.     

Formation of a nickel catalyst on the surface of aluminosilicate supports for the synthesis of catalytic fibrous carbon

Conditions for the homogeneous precipitation of nickel hydroxide in the presence of urea onto the surface of aluminosilicate honeycomb monoliths, which were prepared based on clay, talc, and amorphous aluminum hydroxide, were examined. Factors affecting the concentration of supported nickel (synthesis time, starting solution concentrations, loaded amount of the support, and support calcination temperature) were studied. The possibility of supporting nickel hydroxide onto the surface of cellular ceramic foam, glass foam, and haydite was demonstrated. The morphology of nickel hydroxide particles, nickel metal particles on support surfaces, and carbon coatings synthesized in the course of the catalytic pyrolysis of a propane-butane mixture was studied by scanning electron microscopy.     

Structural Characteristics and Permeability of Ethyl Cellulose Films Containing Different Plasticizers

The effect of different type of plasticizers was investigated in ethyl cellulose as coating polymer for manufacturing coated pellets of modified release containing a water soluble model drug. Scanning electron microscopic image analysis (SEM), differential scanning calorimetry (DSC), X-ray photoelectron spectroscopic chemical surface analysis (XPS) were used to study the films, and the dissolution profiles of coated pellets were evaluated. The effect of the different plasticizers and coating levels on the first order dissolution rate constant is determined by statistical experimental design. Correlation was found between the dissolution rate constant and the structural characteristics of the coating layer containing different plasticizers. Partial segregation of the plasticizers was detected especially on the surface of the films, which is in correlation with the differences in the glass transition temperatures. PEG 400 is found to be compatible enough to form continuous, durable EC coating at 5% concentration level, which gave the slowest dissolution.     

A study on superhydrophobic coating in anti-icing of glass/porcelain insulator

This paper focuses on the preparation of a superhydrophobic coating on glass/porcelain insulators which possess anti-icing property below freezing temperature. Inspired by lotus-effect, the fabrication of a superhydrophobic coating has two steps: the first step is to construct a hierarchical SiO₂ coating on the substrate surface, and the second step is the chemical modification of the SiO₂ coating with 1H,1H,2H,2H-Perfluorodecyltriethoxysilane (PDTS). The precursor for the hierarchical SiO₂ coating is a suspension of SiO₂ sol particles and dispersible SiO₂ powder particles. According to the TEM testing, SiO₂ sol particles prepared by sol–gel method has an average particle size about 2–5 nm, while the size of the dispersible SiO₂ particles is ca. 20 nm. The precursor was sprayed on glass/porcelain insulators, and then dried at ambient condition, finally heat-treated at 773 K for 2 h. The morphology of the superhydrophobic coating was characterized by TEM and AFM, and experimental results indicated that the coating featured [hierarchical structure consisting of both large bumps with micron-sized height (0.8 μm) and tiny papillae with the size about 30 nm] micron-sized roughness (0.8 μm) combined with nano-sized roughness (about 2 nm). Moreover, the scratch test showed that the coating tightly adhered to the surface of the glass/porcelain insulators. The superhydrophobic property of the coating was examined by a contact angle measurement, and the results demonstrated that the static water contact angle is high up to 163.6°, and the sliding angle is 1.4°. The superhydrophobic property of the coating was also confirmed by the outdoor tests in winter, and it was found that the superhydrophobic coating had the function in anti-icing, based on which the anti-icing mechanism underlying was discussed in terms of the interaction between impacting droplets and superhydrophobic surface.     

脉冲复合镀涂层的制备及其高温氧化动力学

水基体系内采用脉冲复合电镀法将镍包铝粉镀到普通碳钢（A3）表面,并与直流电镀结果进行了比较。 结果显示,脉冲复合镀镀层晶粒大小均匀,结合紧密,晶相稳定,镀覆完整,经过热处理,镀层与基体金属之间相互渗透并形成金属间化合物,与钢基体结合牢固,热重分析实验显示此脉冲复合镀镀层经过热处理后显著提高了基体的高温抗氧化性。     

Atomic force microscopy of coated glasses

Atomic force microscopy has been used to investigate the topology of alkoxide gel dip coatings on different substrates. Results of SiO₂ – TiO₂ – ZrO₂ (STZ) coatings are presented on float glass, on polished fused silica, on commercially coated insulating flat glass, and on PtRh.· Consolidated STZ coatings display the so-called glass pattern with ripples equal or less than 2 nm high. The same pattern is seen on partially dense STZ coatings, as soon as the surface is stiff enough for scanning, and also on the bottom of a 50 nm deep sputtering crater in the consolidated coating.· The vitreous STZ coating on the fire side of the float glass is as flat as the float glass itself. It has the same tendency to contamination. 100 nm wide and 50 nm deep polishing grooves on fused silica have been filled up with the 80 nm thick coating, only dips of a few nm remain. The trenches between the SnO₂ crystallites on the insulating flat glass were filled up and the roughness of the substrate was partially reduced. PtRh sheet remained rough even after the coating.· On the partially densified STZ coating, sputtering generates a grained surface.     

全氟丙烯酸酯聚合物乳液研究进展

全氟丙烯酸酯聚合物乳液由于具有优异的表面特性，耐候性及环境友好性，可望在建筑涂料、纺织工业以及其它重要领域得到广泛的应用。本文综述了全氟丙烯酸酯聚合物的特性及乳液的合成方法与应用，介绍了国内外在此领域的研究状况。     

The new idea for modification of the surface area of silicate glass

The paper presents a new and original method of modifying the surface layer of silicate glass by applying a coating produced from zirconium oxide–yttria-stabilized powder using the LPPS plasma method (low-pressure plasma spraying). This is a new approach and not found in both scientific literature and known technological solutions. The results of the work indicate that it is possible to produce the coatings of yttrium-stabilized zirconium oxide (YSZ) on the glass substrate. These coatings were made using the LPPS PS-PVD method and consist of fine YSZ crystals with spheroidal morphology. This gradient coating (FGM) has a thickness controlled from LPPS of several dozen to hundreds of nanometers. It effectively modifies the properties of the glass by introducing favorable stresses on the surface and therefore increases its hardness and tensile strength. At the same time, thermal properties of the glass were determined, which allowed to determine the temperature of heating the glass substrate necessary for the proper implementation of the oxide coating production process on this substrate by the LPPS method. The glass parameters achieved in the work are very promising and comparable with the characteristics of the best glasses currently used in optoelectronics, especially in the displays of mobile phones and solar cells.

     

纳米二氧化硅对镍电沉积影响及在复合镀层中的化学键合状态

用线性扫描伏安法和电位阶跃法研究了n-SiO2/Ni复合电刷镀体系的电化学响应,探讨了纳米颗粒的影响;用X射线光电子谱研究了复合镀层中n-SiO2/Ni颗粒表面与基质金属间的相互作用．结果表明纳米颗粒使金属沉积过电位显著降低,电流效率、金属成核率及晶体生长速度增加,纳米颗粒对金属镍电结晶有明显的催化效应;n-SiO2/Ni表面氧的不饱和化学键与表面扩散过程中吸附态金属Ni原子键合形成Ni-O键,纳米颗粒与基质镍以化学键方式结合．     

Some investigations into the coating of glass open-tube columns

Summary The etching of soda glass by hydrogen chloride has been studied by determining the weight of sodium chloride per unit area on single and double statically-etched glass. The influence of three coating solvents on the critical surface tension of etched and unetched glass has been determined by measuring the contact angles of a wide range of stationary phases. The dynamic coating procedure has been critically examined and certain aspects which lead to the production of improved columns are explored.