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Artificially modified IgG molecules are increasingly utilized in industrial and clinical applications. In the present study, the method of chemical conjugation by affinity peptide (CCAP) for site-specific chemical modification has been developed by using a peptide that bound with high affinity to human IgG-Fc. This method enabled a rapid modification of a specific residue (Lys248 on Fc) in a one-step reaction under mild condition to form a stable amide bond between the peptide and Fc. The monovalent peptide-IgG conjugate not only maintained complete antigen binding but also bound to Fc receptors (FcRn, FcγRI, and FcγRIIIa), indicating that it is a suitable conjugate form that can be further developed into highly functional antibody therapeutics. CCAP was applied for the preparation of an antibody-drug conjugate and a bispecific antibody to demonstrate the usefulness of this method.

We first report a fabrication technique of nanoscale speckle patterns on polymers using broad ion beam milling. The proposed technique is simple and low-cost to produce speckles ranging from dozens of nanometers to less than three micrometers in a large area of several millimeters. Random patterns were successfully produced with an argon (Ar) ion beam on the surfaces of four kinds of polymers: the epoxy matrix of carbon fiber reinforced plastic, polyester, polyvinyl formal-acetal, and polyimide. The speckle morphologies slightly vary with different polymers. The fabricated speckle patterns have good time stability and are promising to be used to measure the nanoscale deformations of polymers using the digital image correlation method.

Multi-scale grid is an essential deformation carrier in optical methods for multi-scale deformation measurement. In this study, several new-type multi-scale grids were designed and fabricated by electron beam lithography. Each pattern includes several periodically distributed dots with the same spacing but different sizes. As a consequence, the grayscale of the whole grid pattern periodically changes. The peak parts of the grayscale generate a secondary grid, i.e., the large-scale grid. The ratio of the large-scale grid pitch to the small-scale grid pitch can be easily adjusted according to the requirement. The natural integration between the small-scale grid and the large-scale grid works well in eliminating the mutual disturbance between the different-scale grids. Besides, this type of grid has a very high success rate in fabrication owing to the small differences in size between the big dots and the small dots. The proposed multi-scale grid pattern is expected to serve as the deformation carrier in moiré methods and geometric phase analysis for multi-scale deformation measurement.

The buckling behavior of a typical structure consisting of a micro constantan wire and a polymer membrane under coupled electrical-mechanical loading was studied. The phenomenon that the constantan wire delaminates from the polymer membrane was observed after unloading. The interfacial toughness of the constantan wire and the polymer membrane was estimated. Moreover, several new instability modes of the constantan wire could be further triggered based on the buckle-driven delamination. After electrical loading and tensile loading, the constantan wire was likely to fracture based on buckling. After electrical loading and compressive loading, the constantan wire was easily folded at the top of the buckling region. On the occasion, the constantan wire buckled towards the inside of the polymer membrane under electrical-compressive loading. The mechanisms of these instability modes were analyzed.

Metallic closed cellular materials containing polymer were fabricated by the penetrating polymer into metal foam. The aluminum and stainless steel foams were selected for the metal foam and epoxy resin and polyurethane resin were selected for the penetrated polymer. The many kinds of mechanical properties of this material were measured. The results of the compressive tests show that these materials have different stress-strain curves among the specimens that containing different materials in the cells. Also, this metallic closed cellular materials containing polymer have higher compressive strength, higher Young’s modules, higher energy absorption and higher internal friction than that of metallic closed cellular material without any polymer.

New methods to fabricate a metallic closed cellular material for smart materials using an isostatic pressing and penetrating method are introduced. Powder particles of polymer or ceramics coated with a metal layer using electro-less plating were pressed into pellets and sintered at high temperature. These powder particles were sintered by spark plasma sintering (SPS) method. Closed cellular materials including polymer were fabricated by penetrating polymer into metallic foams. Many kinds of metallic closed cellular materials including different materials from that of cell walls were tried to fabricate. The physical and mechanical properties of these materials were measured. The results of the compressive tests show that this material has high-energy absorption and the result of measuring the internal friction show that the internal friction of these materials is larger than that of pure aluminum.

Here, we demonstrate a new method to measure the domain sizes and the periodicities of the pore arrangements and to find the domain boundaries in the designed PAA film with conical nanopores. Such structural information can be simultaneously obtained by utilizing the electron moiré fringes without direct observation of the nanopores. The electron moiré fringes are generated by overlapping of two patterns on the basis of the principle of the traditional moiré method. The average size of the single domains is estimated to be about 2 μm2. Furthermore, the Ni cone arrays are successfully produced by replication method using the PAA film. Very clear electron moiré fringes can be visualized on the surface of the Ni cone arrays. The domain-shape and the average domain-size in the observed moiré fringes are almost similar to those of the PAA film used as the original template. This fact indicates that the Ni cones are successfully replicated under excellent electrochemical conditions.

In this paper, scanning electron moiré method is used to measure the mechanical behavior of Ferro-based shape memory alloys(SMA). The moiré patterns are formed by the interference between a 1000 lines/mm cross-type specimen grating (which is fabricated using electron beam lithography) and the scanning lines of Scanning Electron Microscope (SEM). When the specimen is subjected to uniform tension load at the room temperature, the unloading residual strain values in the different regions under the same tensile load and the values in the same region under different tensile loads are compared respectively. The shape memory effect is also studied. From the experimental results, it can be concluded that the proposed moiré method is highly accurate to measure the mechanical behavior of microscopic field.

Abstract: Recently, the thermal-spray community has focused considerable attention on cold-spray and warm-spray techniques, in which the temperatures of sprayed particles are kept below their melting point and adhesion occurs based on the impact phenomenon between a solid particle and a substrate. The mechanisms of adhesion are still unclear, but the degree of the mechanical deformation at the interface is considered to be a key factor influencing this mechanism. However, it is very difficult to directly measure the strain at the interface. Instead, in this work, the strain fields on a substrate around an impacted particle sprayed by warm-spray deposition were measured by applying electron Moiré method, and compared with numerical simulation results.

Scanning electron microscopic (SEM) moiré method was used to study the surface structure of three kinds of butterfly wings: Papilio maackii Menetries, Euploea midamus (Linnaeus), and Stichophthalma howqua (Westwood). Gratings composed of curves with different orientations were found on scales. The planar characteristics of gratings and some other planar features of the surface structure of these wings were revealed, respectively, in terms of virtual strain. Experimental results demonstrate that SEM moiré method is a simple, nonlocal, economical, effective technique for determining which grating exists on one whole scale, measuring the dimension and the whole planar structural character of the grating on each scale, as well as characterizing the relationship between gratings on different scales of each butterfly wing. Thus, the SEM moiré method is a useful tool to assist with characterizing the structure of butterfly wings and explaining their excellent properties.

A method to fabricate the metallic closed cellular material has been developed. Powder particles of polymer or ceramics coated with a metal layer using electro-less plating were pressed into pellets and sintered at high temperatures by heating and spark plasma sintering (SPS) method. A metallic closed cellular material containing different materials from that of cell walls was then fabricated. The mechanical and Thermal properties of this material were measured. The results of the compressive tests show that this material has the different stress-strain curves among the specimens that have different thickness of the cell walls and the sintering temperatures of the specimens affect the compressive strength of each specimen. Also, it seems that the results of the compressive tests show that this material has high-energy absorption and Young’s modulus of this material depends on the thickness of the cell walls. Also thermal properties of this material were measured.

A method for measuring the stress and strain distribution in the composite materials and residual stress at the interface in the fiber reinforced composite has been developed. The strains are measured using an electron Moiré method and then the stresses are calculated from these strains. A very fine model grid with frequencies up to 10,000lines/mm can be fabricated using the optical and electron lithography techniques on the surface of the specimen and an electron beam scan which spaces are almost same as that of model grid the can be used for master-grid. The difference of the amount of secondary electrons per a primary electron makes Moiré fringes that consists bright and dark parts. Micro-creep deformation and residual strain and stress near the fibers of composite materials were measured by this method.

Several methods of fabricating metallic closed cellular materials a spark plasma sintering (SPS) system have been developed. Powdered polymer particles coated with a nickel-phosphorus alloy layer using electro-less plating were pressed into pellets and sintered at high temperatures in a furnace using SPS system. Metallic closed cellular materials containing different materials from the cell walls were then fabricated. The physical, mechanical and damping properties of these materials were measured. The results of the compressive tests show that this material has different stressstrain curves among the specimens that have different cell wall thicknesses and the sintering temperatures of the specimens affect the compressive strength of each specimen. Also, it seems that the results of the compressive tests show that this material has a high-energy absorption. The internal friction of this material was measured and the results show that this internal friction is the same as that of pure aluminum. These results suggest that this material can be utilized as an energy absorbing and passive damping material.

The electron moiré method uses a high frequency grating to measure microscopic deformation. Finer and finer gratings are being pursued to meet higher and higher resolution requirements in microscopic stress analysis. In this study, the techniques of fabricating electron grid by means of a scanning electron microscope are improved. The use of a low accelerating voltage shows a better effect than the high accelerating voltage in fabricating a superfine grid. A new group of parameters is suggested based on this consideration. A cross-line grid with a frequency of 10,000 lines/mm and a parallel grating with a frequency of 13,000 lines /mm have been successfully fabricated.

In this paper, a new scanning moiré method is developed to measure the in-plane deformation of mica using an atomic force microscope (AFM). Moiré patterns are formed by the scanning line of the CRT in the AFM system, and the atomic lattice of the mica or high-orientated pyrolytic graphite (HOPG). The measurement principle and the techniques employed for grating preparation are described in detail. This new method is used to measure the residual deformation of a mica plate after irradiation by a Nd-YAG laser, and to determine the residual strain of HOPG under a tensile load. Some interesting results are obtained. The successful results verify the feasibility of this method for measuring deformation in the nanometre range using the lattice of the material as the model grid.

The dynamic deformations of impulsed viscoelastic plates measured with the moire method are discussed. A new method for producing visco-photoelastic material is proposed. The material was processed as plate type specimens with elliptical or circular holes, and utilized to investigate its dynamic deformation behavior at 42°C. The measuring method and procedures, as well as the experimental results are discussed in detail.

A technique for measuring the contour of a specimen’s surface is developed. A small microdevice produced by a micromachining technique and the electron beam scan of a scanning electron microscope (SEM) are used for this method. A small microgrid consisting of microsquare bars is placed over the specimen’s surface and obstructs the back-scattered electrons. Therefore, the shadows of the microbars are observed in the SEM image. The distance between the microgrid and the specimen’s surface can be calculated using the width of the shadow. This method makes it possible to detect the form of the specimen’s surface. As a demonstration, the shape of the Rockwell hardness tester’s indent mark is measured and the accuracy of this method is discussed. © 1997 Society of Photo-Optical Instrumentation Engineers.

The dissociation of 4-(4-nitrophenylazo)-1-naphthol (azo dye) in pyridine was found to be accelerated by the addition of small amounts of quaternary ammonium compounds, R4N+X−. The apparent equilibrium constant of the azo dye was influenced enormously by the species of X−, but was little affected by the structures of R. The effect increased as the X−became more basic, ClO4−

We present the hexagonal digital moiré method for three-directional structural characterization of hexagonal packed nanostructures. A mismatch between a three-way grating and a nanoparticle assembly is shown to produce hexagonal moiré fringes due to the interference between three groups of parallel moiré patterns. The measuring principles of the pitches and the orientations of the three 1D arrays of the nanoparticles are presented. The structural information on a silica nanoparticle assembly is analyzed.

The femtosecond laser exposure system was used to fabricate model grids for the charge-coupled device (CCD) moiré method, scanning laser moiré method, and electron moiré method for microstrain deformation measurements. The femtosecond laser exposure produces mesoscopic variation patterns on the surface. These variation patterns make the grid in the scanning laser microscope and CCD images darker and make the grid in the scanning electron microscope image brighter. The CCD moiré fringe, scanning laser moiré fringe, and electron moiré fringe consisting of bright and dark lines were generated. As a demonstration, microstrain distribution of the three-point bending tested specimen was measured.

This paper explores the planar arrangement feature of the copper interconnects in a view field of several millimeters by the focused ion-beam (FIB) Moiré inversion method quantitatively. The curved FIB Moiré patterns indicate that the copper interconnects are a series of curves with continuous variations instead of beelines. The control equation set of the copper interconnects central lines is attained through the Moiré inversion method. This work can be extended to inspect the structural defects and provide a reliable support for the interconnects structure fabrication.

It is very important to measure local deformations for an in-depth understanding of mechanical properties and fracture mechanism of structural and functional materials. In this paper, different types of model grid fabrication methods and many types of electron Moiré methods using an electron beam drawing system, a scanning electron microscope or a focus ion beam are reported, together with their applications in the measurement of deformations occurring in various engineerings and materials science research.