Complementary physicochemical analysis by ellipsometry and Auger spectroscopy of nano-sized protective coating layers

Diamond-like carbon (DLC) coating is becoming a promising protective coating layers due to its superior properties. In this study, instead of protective coating, DLC film was applied as the only component for micropattern then etched with lithography and lift-off process selectively. Furthermore, DLC film has been fabricated on aluminum roll mold. Then UV curing resin was applied to form the pattern on the polyethylene terephthalate (PET) film. The dimension and formation of the DLC micropattern on roll mold were analyzed. Moreover, the Raman spectroscopic of nitrogen-doped DLC film was analyzed.

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The many faces of STEM in materials science

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100086507 ◽

1991 ◽

Vol 49 ◽

pp. 440-441

Author(s):

John Silcox

Keyword(s):

Materials Science ◽

Auger Spectroscopy ◽

Dark Field ◽

High Tc Superconductors ◽

High Tc ◽

Acoustic Environment ◽

Electromagnetic Vibration ◽

The Many ◽

Serial Mode

Determination of the microstructure and microchemistry of small features often provides the insight needed for the understanding of processes in real materials. In many cases, it is not adequate to use microscopy alone. Microdiffraction and microspectroscopic information such as EELS, X-ray microprobe analysis and Auger spectroscopy can all contribute vital parts of the picture. For a number of reasons, dedicated STEM offers considerable promise as a quantitative instrument. In this paper, we review progress towards effective quantitative use of STEM with illustrations drawn from studies of high Tc superconductors, compound semiconductors and metallization of H-terminated silicon.Intrinsically, STEM is a quantitative instrument. Images are acquired directly by detectors in serial mode which is particularly convenient for digital image acquisition, control and display. The VG HB501A at Cornell has been installed in a particularly stable electromagnetic, vibration and acoustic environment. Care has been paid to achieving UHV conditions (i.e., 10-10 Torr). Finally, it has been interfaced with a VAX 3200 work station by Kirkland. This permits, for example, the acquisition of bright field (or energy loss) images and dark field images simultaneously as quantitative arrays in perfect registration.

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Design of a UHV STEM for Through-The-Lens Electron Spectroscopy

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100135502 ◽

1990 ◽

Vol 48 (2) ◽

pp. 380-381

Author(s):

A. J. Bleeker ◽

P. Kruit

Keyword(s):

Secondary Electron ◽

High Vacuum ◽

Secondary Electron Emission ◽

Auger Spectroscopy ◽

Scanning Transmission Electron Microscope ◽

Point Of View ◽

Ultra High Vacuum ◽

Scanning Transmission ◽

Auger Spectra ◽

Coincidence Measurements

Combining of the high spatial resolution of a Scanning Transmission Electron Microscope and the wealth of information from the secondary electrons and Auger spectra opens up new possibilities for materials research. In a prototype instrument at the Delft University of Technology we have shown that it is possible from the optical point of view to combine STEM and Auger spectroscopy [1]. With an Electron Energy Loss Spectrometer attached to the microscope it also became possible to perform coincidence measurements between the secondary electron signal and the EELS signal. We measured Auger spectra of carbon aluminium and Argon gas showing energy resolutions better than 1eV [2]. The coincidence measurements on carbon with a time resolution of 5 ns yielded basic insight in secondary electron emission processes [3]. However, for serious Auger spectroscopy, the specimen needs to be in Ultra High Vacuum. ( 10−10 Torr ). At this moment a new setup is in its last phase of construction.

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Discrete element method to model cracking for two layer systems

TAPPI Journal ◽

10.32964/tj18.2.101 ◽

2019 ◽

Vol 18 (2) ◽

pp. 101-108

Author(s):

Daniel Varney ◽

Douglas Bousfield

Keyword(s):

Discrete Element Method ◽

Flexural Modulus ◽

Single Layer ◽

Discrete Element ◽

Flexural Stress ◽

Layer System ◽

Three Point Bending ◽

Moving Force ◽

Coating Layers ◽

Element Method

Cracking at the fold is a serious issue for many grades of coated paper and coated board. Some recent work has suggested methods to minimize this problem by using two or more coating layers of different properties. A discrete element method (DEM) has been used to model deformation events for single layer coating systems such as in-plain and out-of-plain tension, three-point bending, and a novel moving force picking simulation, but nothing has been reported related to multiple coating layers. In this paper, a DEM model has been expanded to predict the three-point bending response of a two-layer system. The main factors evaluated include the use of different binder systems in each layer and the ratio of the bottom and top layer weights. As in the past, the properties of the binder and the binder concentration are input parameters. The model can predict crack formation that is a function of these two sets of factors. In addition, the model can predict the flexural modulus, the maximum flexural stress, and the strain-at-failure. The predictions are qualitatively compared with experimental results reported in the literature.

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Cracking at the fold in double layer coated paper: the influence of latex and starch composition

TAPPI Journal ◽

10.32964/tj18.2.93 ◽

2019 ◽

Vol 18 (2) ◽

pp. 93-99

Author(s):

SEYYED MOHAMMAD HASHEMI NAJAFI ◽

DOUGLAS BOUSFIELD, ◽

MEHDI TAJVIDI

Keyword(s):

Mechanical Properties ◽

Double Layer ◽

Starch Content ◽

Single Layer ◽

Double Layers ◽

Coated Paper ◽

Coated Papers ◽

Coating Layers ◽

Scanned Images ◽

Packaging Paper

Cracking at the fold of publication and packaging paper grades is a serious problem that can lead to rejection of product. Recent work has revealed some basic mechanisms and the influence of various parameters on the extent of crack area, but no studies are reported using coating layers with known mechanical properties, especially for double-coated systems. In this study, coating layers with different and known mechanical properties were used to characterize crack formation during folding. The coating formulations were applied on two different basis weight papers, and the coated papers were folded. The binder systems in these formulations were different combinations of a styrene-butadiene latex and mixtures of latex and starch for two different pigment volume concentrations (PVC). Both types of papers were coated with single and double layers. The folded area was scanned with a high-resolution scanner while the samples were kept at their folded angle. The scanned images were analyzed within a constant area. The crack areas were reported for different types of papers, binder system and PVC values. As PVC, starch content, and paper basis weight increased, the crack area increased. Double layer coated papers with high PVC and high starch content at the top layer had more cracks in comparison with a single layer coated paper, but when the PVC of the top layer was low, cracking area decreased. No measurable cracking was observed when the top layer was formulated with a 100% latex layer.

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PHYSICOCHEMICAL ANALYSIS OF GROUND WATER AND SURFACE WATER IN KOTA REGION, RAJASTHAN, INDIA

FLORA AND FAUNA ◽

10.33451/florafauna.v24i1pp177-182 ◽

2018 ◽

Vol 24 (1) ◽

Author(s):

NITU SINGH ◽

FATIMA SULTANA

Keyword(s):

Surface Water ◽

Ground Water ◽

Growth And Development ◽

Physicochemical Parameters ◽

Total Dissolved Solids ◽

Physicochemical Analysis ◽

Total Hardness ◽

Developing Nation ◽

The Sustainable Development ◽

Chloride Sulfate

India is a developing nation and is dependent on its natural resources for growth and development. Water, being one of the vital natural resource, must be used judicially for the sustainable development. Present study focuses on the analysis of physicochemical parameters (pH, Turbidity, Alkalinity, Total Hardness, Total dissolved solids, Conductivity, Chloride, Sulfate, Fluoride contents) of ground water and surface water in Kota City (Rajasthan). The study shows the adverse impact of exploitation and urbanization on water resources of Kota City (Rajasthan). Some physicochemical parameters exceed the desirable limits as defined by WHO and Indian Standards in the selected sites. The level of pollution in ground water and surface water of Kota City is increasing due to urbanization.

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CAD Of Anticorrosive Protection Of Steel Structures

Promyshlennoe i Grazhdanskoe Stroitel stvo ◽

10.33622/0869-7019.2019.09.18-23 ◽

2019 ◽

pp. 18-23

Keyword(s):

Protective Coating ◽

Computer Aided Design ◽

Steel Structures ◽

Cost Effective ◽

Operating Conditions ◽

Computational Tool ◽

Protection Method ◽

Cost Effective Method ◽

The Cost ◽

Aided Design

The choice of cost-effective method of anticorrosive protection of steel structures is an urgent and time consuming task, considering the significant number of protection ways, differing from each other in the complex of technological, physical, chemical and economic characteristics. To reduce the complexity of solving this problem, the author proposes a computational tool that can be considered as a subsystem of computer-aided design and used at the stage of variant and detailed design of steel structures. As a criterion of the effectiveness of the anti-corrosion protection method, the cost of the protective coating during the service life is accepted. The analysis of existing methods of steel protection against corrosion is performed, the possibility of their use for the protection of the most common steel structures is established, as well as the estimated period of effective operation of the coating. The developed computational tool makes it possible to choose the best method of protection of steel structures against corrosion, taking into account the operating conditions of the protected structure and the possibility of using a protective coating.

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