Enhancement of optical and mechanical properties of Si nanopillars by ALD TiO2 coating

The study presents the results of the experimental action of laser radiation with a wavelength of 532 nm in continuous contact mode on biological tissues with different optical properties. The width of the ablation and coagulation zone, the degree of vaporization of various types of tissues were evaluated. Good coagulation properties of the laser are established when exposed to pigmented tissues. However, the pronounced color dependence characteristic of a given wavelength requires careful selection of the biological objects that are suitable for optical properties. Objectives: An experimental evaluation of the effects of a laser with a wavelength of 532 nm in a continuous contact mode on tissues with different optical and mechanical properties. Materials and methods. We carried out an experimental study of the effects of a laser with a wavelength of 532 nm in a continuous contact mode on biological tissues with different optical and mechanical properties. The crater width and side coagulation zone were measured using an operating microscope and a glass slide with a scale value of 0.1 mm. The tissue samples were weighed before and after the application of a point impact. The increase in laser power contributes to an increase in the width of the incision and the coagulation zone. A more pronounced adhesion of the tissue to the fiber end was noted when exposed to the liver tissue of cattle, which causes smaller values of the ablation zone width in comparison with the muscle tissue of the chicken and is reflected in high values of the error of the mean values. The greatest weight loss with a 2 seconds point impact at a power of 5 W was determined on the muscle tissue of the chicken. Conclusions. Good coagulation properties of the laser have been established when exposed to pigmented tissues, however, the pronounced color dependence characteristic of a given wavelength requires careful selection of the biological objects suitable for optical properties.

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Redesign of Carbon Materials for Novel Storage, Mechanical and Optical Properties

MRS Proceedings ◽

10.1557/opl.2012.1451 ◽

2012 ◽

Vol 1451 ◽

pp. 9-14

Author(s):

Stefano Leoni ◽

Igor A. Baburin ◽

S. E. Boulfelfel ◽

D. Selli

Keyword(s):

Mechanical Properties ◽

Optical Properties ◽

Carbon Nanotube ◽

Numerical Methods ◽

Carbon Materials ◽

Scaling Up ◽

Ambient Conditions ◽

Technological Potential ◽

Optical And Mechanical Properties

ABSTRACTWe revisit the polymorphism of carbon along two directions. First, we discover novel polymorphs in the vicinity of graphite, with outstanding optical and mechanical properties. Using numerical methods and graph-theoretical tools, we find as many as 4 novel superhard and transparent polymorphs, with great technological potential. Second, scaling up a model of rod packing to carbon nanotube (CNT) scaffoldings, we discover that such complex assemblies of CNTs are outstanding adsorbers of hydrogen, capable of reaching the DOE target (~6.0 wt% at ambient conditions). Along this line, we highlight novel paradigms for revisiting carbon, in view of remarkable qualities and superior properties.

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DFT Study of Electronic Structure and Optical Properties of Kaolinite, Muscovite, and Montmorillonite

Crystals ◽

10.3390/cryst11060618 ◽

2021 ◽

Vol 11 (6) ◽

pp. 618

Author(s):

Layla Shafei ◽

Puja Adhikari ◽

Wai-Yim Ching

Keyword(s):

Mechanical Properties ◽

Optical Properties ◽

Electronic Structure ◽

Hydrogen Bonds ◽

Clay Minerals ◽

Clay Mineral ◽

Bond Order ◽

Deep Understanding ◽

Pharmaceutical Applications ◽

Structure Properties

Clay mineral materials have attracted attention due to their many properties and applications. The applications of clay minerals are closely linked to their structure and composition. In this paper, we studied the electronic structure properties of kaolinite, muscovite, and montmorillonite crystals, which are classified as clay minerals, by using DFT-based ab initio packages VASP and the OLCAO. The aim of this work is to have a deep understanding of clay mineral materials, including electronic structure, bond strength, mechanical properties, and optical properties. It is worth mentioning that understanding these properties may help continually result in new and innovative clay products in several applications, such as in pharmaceutical applications using kaolinite for their potential in cancer treatment, muscovite used as insulators in electrical appliances, and engineering applications that use montmorillonite as a sealant. In addition, our results show that the role played by hydrogen bonds in O-H bonds has an impact on the hydration in these crystals. Based on calculated total bond order density, it is concluded that kaolinite is slightly more cohesive than montmorillonite, which is consistent with the calculated mechanical properties.

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Intriguing electronic, optical and mechanical properties of the vertical and lateral heterostructures on the boron phosphide and GaN monolayers

Journal of Materials Science ◽

10.1007/s10853-021-05785-6 ◽

2021 ◽

Vol 56 (12) ◽

pp. 7451-7463

Author(s):

Yusheng Wang ◽

Xiaowei Wu ◽

Nahong Song ◽

Xiaohui Yang ◽

Yafeng Zheng ◽

...

Keyword(s):

Mechanical Properties ◽

Boron Phosphide ◽

Optical And Mechanical Properties

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Structural and physical properties of 99 complex bulk chalcogenides crystals using first-principles calculations

Scientific Reports ◽

10.1038/s41598-021-89281-6 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Sahib Hasan ◽

Khagendra Baral ◽

Neng Li ◽

Wai-Yim Ching

Keyword(s):

Mechanical Properties ◽

Physical Properties ◽

First Principles ◽

Experimental Studies ◽

First Principles Calculations ◽

Chalcogenide Semiconductors ◽

Optical And Mechanical Properties ◽

Very Large Database ◽

Unique Composition ◽

Fundamental Physical

AbstractChalcogenide semiconductors and glasses have many applications in the civil and military fields, especially in relation to their electronic, optical and mechanical properties for energy conversion and in enviormental materials. However, they are much less systemically studied and their fundamental physical properties for a large class chalcogenide semiconductors are rather scattered and incomplete. Here, we present a detailed study using well defined first-principles calculations on the electronic structure, interatomic bonding, optical, and mechanical properties for 99 bulk chalcogenides including thirteen of these crytals which have never been calculated. Due to their unique composition and structures, these 99 bulk chalcogenides are divided into two main groups. The first group contains 54 quaternary crystals with the structure composition (A2BCQ4) (A = Ag, Cu; B = Zn, Cd, Hg, Mg, Sr, Ba; C = Si, Ge, Sn; Q = S, Se, Te), while the second group contains scattered ternary and quaternary chalcogenide crystals with a more diverse composition (AxByCzQn) (A = Ag, Cu, Ba, Cs, Li, Tl, K, Lu, Sr; B = Zn, Cd, Hg, Al, Ga, In, P, As, La, Lu, Pb, Cu, Ag; C = Si, Ge, Sn, As, Sb, Bi, Zr, Hf, Ga, In; Q = S, Se, Te; $$\hbox {x} = 1$$ x = 1 , 2, 3; $$\hbox {y} = 0$$ y = 0 , 1, 2, 5; $$\hbox {z} = 0$$ z = 0 , 1, 2 and $$\hbox {n} = 3$$ n = 3 , 4, 5, 6, 9). Moreover, the total bond order density (TBOD) is used as a single quantum mechanical metric to characterize the internal cohesion of these crystals enabling us to correlate them with the calculated properties, especially their mechanical properties. This work provides a very large database for bulk chalcogenides crucial for the future theoretical and experimental studies, opening opportunities for study the properties and potential application of a wide variety of chalcogenides.

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