Study of Non-Aqueous Passivation on GaSb (100) Surfaces

MRS Proceedings ◽

10.1557/proc-763-b2.3 ◽

2003 ◽

Vol 763 ◽

Cited By ~ 4

Author(s):

Z.Y. Liu ◽

T.F. Kuech ◽

D.A. Saulys

Keyword(s):

Sodium Sulfide ◽

Chemical Reactivity ◽

Chemical Properties ◽

Chelating Agent ◽

Oxide Content ◽

High Chemical ◽

Lower Oxide ◽

Surface Optical ◽

Surface Oxides ◽

And Chemical Properties

AbstractDue to the high chemical reactivity of GaSb surfaces, many commonly used aqueous sulfide passivation techniques lead to the growth of surface oxides that degrade device performance. We have developed a non-aqueous passivation regime consisting of Na2S/benzene/15-crown-5/oxidant. The use of a non-polar, aprotic organic medium required the addition of a specific chelating agent, i.e. a 15-crown-5 ether, to solubilize sodium sulfide, and organic oxidizing agents, such as anthraquinone and benzophenone, to act as electron acceptors. The surface optical and chemical properties of GaSb surfaces after aqueous and non-aqueous sulfide treatments were compared. Non-aqueous passivation resulted in higher PL intensity, lower oxide content, and a less amount of elemental Sb than aqueous passivation.

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Topological invariants for the line graphs of some classes of graphs

Open Chemistry ◽

10.1515/chem-2019-0154 ◽

2019 ◽

Vol 17 (1) ◽

pp. 1483-1490

Author(s):

Xiaoqing Zhou ◽

Mustafa Habib ◽

Tariq Javeed Zia ◽

Asim Naseem ◽

Anila Hanif ◽

...

Keyword(s):

Communication Theory ◽

Chemical Reactivity ◽

Line Graph ◽

Chemical Properties ◽

Topological Invariants ◽

Line Graphs ◽

Physical And Chemical Properties ◽

Physical And Chemical ◽

Ladder Graphs ◽

And Chemical Properties

AbstractGraph theory plays important roles in the fields of electronic and electrical engineering. For example, it is critical in signal processing, networking, communication theory, and many other important topics. A topological index (TI) is a real number attached to graph networks and correlates the chemical networks with physical and chemical properties, as well as with chemical reactivity. In this paper, our aim is to compute degree-dependent TIs for the line graph of the Wheel and Ladder graphs. To perform these computations, we first computed M-polynomials and then from the M-polynomials we recovered nine degree-dependent TIs for the line graph of the Wheel and Ladder graphs.

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Stabilization Characteristics of Clays Using Class C Fly Ash

Transportation Research Record Journal of the Transportation Research Board ◽

10.3141/1611-06 ◽

1998 ◽

Vol 1611 (1) ◽

pp. 46-54 ◽

Cited By ~ 38

Author(s):

Anil Misra

Keyword(s):

Fly Ash ◽

Chemical Properties ◽

Clay Soils ◽

Statistical Characteristics ◽

Oxide Content ◽

Physical And Chemical Properties ◽

High Calcium ◽

Class C ◽

Physical And Chemical ◽

And Chemical Properties

Coal-burning utilities using subbituminous coal from Wyoming typically produce fly ash, which, because of its high calcium oxide content, may be classified as Class C fly ash. These ashes are characterized by their self-cementing property and therefore can be used for soil improvement. Stabilization characteristics of clay soils blended with Class C fly ash were evaluated. Because fly ash is a by-product, uniformity of its physical and chemical properties is significant for quality control. The statistical characteristics of fly ash physical and chemical properties are obtained and compared with the data in literature. Fly ash is blended with several different clay soils of varying plasticity to study moisture-density relationships and strength behavior of stabilized soils. It is observed that the fly ash used in these experiments has a rapid hydration characteristic. Consequently, higher densities and strengths are achieved when the compaction is performed with little or no delay after the addition of moisture to clay-fly ash blends. Conversely, delayed compaction produces low densities and strength. In addition, it is observed that the stabilization characteristics are closely related to the soil mineral type and plasticity. Results also are presented for strength gain behavior with curing period for the various soil-fly ash blends.

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Conductometric Gas Nanosensors

Journal of Sensors ◽

10.1155/2009/659275 ◽

2009 ◽

Vol 2009 ◽

pp. 1-18 ◽

Cited By ~ 34

Author(s):

Girolamo Di Francia ◽

Brigida Alfano ◽

Vera La Ferrara

Keyword(s):

Room Temperature ◽

Chemical Reactivity ◽

Metal Oxide Nanoparticles ◽

Chemical Properties ◽

Metal Nanowires ◽

Fundamental Properties ◽

Research Activities ◽

Sensor Field ◽

Physical And Chemical ◽

And Chemical Properties

This paper presents a review of the current research activities in the field of gas nanosensors. Nanomaterials are characterized by physical and chemical properties that differ from their macroscopic counterparts and, in particular, by an enhanced chemical reactivity even at room temperature. This effect has stimulated the development of chemical sensors based on several different nanomaterials. Here we focus most attention on carbon nanotubes, silicon and metal oxide nanoparticles and metal nanowires. After introducing a few general definitions a discussion on the fundamental properties of the nanostate used in the sensor field is presented and several nanosensors, based on the aforementioned nanomaterials, are discussed. Finally, some personal conclusions will be drawn.

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Quality Assessment of Shoe Leather Based on the Properties of Strength and Comfort, Collected from Different Footwear and Leather Industries in Bangladesh

Textile & Leather Review ◽

10.31881/tlr.2020.20 ◽

2020 ◽

Author(s):

Md. Delwar Hossain ◽

◽

Forhad Ahammed Bin Azam ◽

Manjushree Chowdhury ◽

◽

...

Keyword(s):

Chemical Properties ◽

Water Vapor Permeability ◽

Rejection Rate ◽

Vapor Permeability ◽

Oxide Content ◽

International Union ◽

Different Types ◽

Physical And Chemical ◽

And Chemical Properties

Based on the environmental condition, a shoe manufactured with different suitable materials has to provide optimum comfort and strength features by using high-quality leather parts. The aim of the study is to evaluate the quality of the shoe upper leather in Bangladesh. Ten different types of shoe leather, made from cow hides and goat skins, were collected from different footwear and leather industries in Bangladesh. The research was carried out by using approved methods of analysis as per the International Union of the Society of Leather Technologists and Chemists’ official methods for physical and chemical analysis. Physical and chemical properties, which were studied three times for each of the samples, were tensile strength, percentage of elongation, tearing strength, grain crack resistance, water vapor permeability, flexing endurance, scuff resistance, perspiration fastness, color rub fastness, bond strength of the finish film, the pH, moisture content, chromic oxide content and fat content, respectively. From the study, it has been revealed that samples 02 and 08 were completely unacceptable, samples 04, 05 and 07 were moderately acceptable, and the remaining samples, 01, 03, 06, 09 and 10, were strongly acceptable on the basis of the ISO standard for shoe leather. To get the better quality, the above mentioned tests should be improved, thus the demand and the value of shoe leather, as well as footwear, will be increased and the rejection rate will be decreased gradually.

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Graphene – Diamond Nanomaterials: A Status Quo Review

10.20944/preprints202107.0647.v1 ◽

2021 ◽

Author(s):

Jana Vejpravová

Keyword(s):

Carbon Nanomaterials ◽

Chemical Reactivity ◽

Experimental Studies ◽

Chemical Properties ◽

Electronic Energy ◽

New Class ◽

Current State ◽

Carbon Networks ◽

Application Potential ◽

And Chemical Properties

Carbon nanomaterials with a different character of the chemical bond – graphene (sp2) and nanodiamond (sp3) are the building bricks for a new class of all-carbon hybrid nanomaterials, where the two different carbon networks with the sp3 and sp2 hybridization coexist, interact and even transform into one another. The unique electronic, mechanical, and chemical properties of the two border nanoallotropes of carbon ensure the immense application potential and versatility of these all-carbon graphene – diamond nanomaterials. The review gives an overview of the current state of the art of graphene – diamond nanomaterials, including their composites, heterojunctions, and other hybrids for sensing, electronic, energy storage, and other applications. Also, the graphene-to-diamond and diamond-to-graphene transformations at the nanoscale, essential for innovative fabrication, and stability and chemical reactivity assessment are discussed based on extensive theoretical, computational, and experimental studies.

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Statistical criteria of stellar population types

Symposium - International Astronomical Union ◽

10.1017/s0074180900053304 ◽

1966 ◽

Vol 24 ◽

pp. 101-110

Author(s):

W. Iwanowska

Keyword(s):

Stellar Population ◽

Chemical Properties ◽

Spectrophotometric Study ◽

Physical And Chemical Properties ◽

Population Type ◽

The Galaxy ◽

Distribution Parameters ◽

Physical And Chemical ◽

Statistical Criteria ◽

And Chemical Properties

In connection with the spectrophotometric study of population-type characteristics of various kinds of stars, a statistical analysis of kinematical and distribution parameters of the same stars is performed at the Toruń Observatory. This has a twofold purpose: first, to provide a practical guide in selecting stars for observing programmes, second, to contribute to the understanding of relations existing between the physical and chemical properties of stars and their kinematics and distribution in the Galaxy.

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The microstructure of a TiB2/Ti-47 Al composite material

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100155347 ◽

1989 ◽

Vol 47 ◽

pp. 674-675

Author(s):

O. Popoola ◽

A.H. Heuer ◽

P. Pirouz

Keyword(s):

Composite Material ◽

Ion Beam ◽

Chemical Properties ◽

Intermetallic Alloys ◽

Transmission Electron ◽

Diamond Polishing ◽

Al Composite ◽

The Matrix ◽

Argon Ion ◽

And Chemical Properties

The addition of fibres or particles (TiB2, SiC etc.) into TiAl intermetallic alloys could increase their toughness without compromising their good high temperature mechanical and chemical properties. This paper briefly discribes the microstructure developed by a TiAl/TiB2 composite material fabricated with the XD™ process and forged at 960°C.The specimens for transmission electron microscopy (TEM) were prepared in the usual way (i.e. diamond polishing and argon ion beam thinning) and examined on a JEOL 4000EX for microstucture and on a Philips 400T equipped with a SiLi detector for microanalyses.The matrix was predominantly γ (TiAl with L10 structure) and α2(TisAl with DO 19 structure) phases with various morphologies shown in figure 1.

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Tailoring microstructures of materials through biomimetics

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100148332 ◽

1993 ◽

Vol 51 ◽

pp. 500-501

Author(s):

Mehmet Sarikaya ◽

Ilhan A. Aksay

Keyword(s):

Chemical Properties ◽

Design And Synthesis ◽

Structure Sensitive ◽

Macro Scale ◽

Methods Of Synthesis ◽

Successive Level ◽

Engineering Materials ◽

Physical And Chemical ◽

And Chemical Properties ◽

Synthesis Of Materials

Biomimetics involves investigation of structure, function, and methods of synthesis of biological composite materials. The goal is to apply this information to the design and synthesis of materials for engineering applications.Properties of engineering materials are structure sensitive through the whole spectrum of dimensions from nanometer to macro scale. The goal in designing and processing of technological materials, therefore, is to control microstructural evolution at each of these dimensions so as to achieve predictable physical and chemical properties. Control at each successive level of dimension, however, is a major challenge as is the retention of integrity between successive levels. Engineering materials are rarely fabricated to achieve more than a few of the desired properties and the synthesis techniques usually involve high temperature or low pressure conditions that are energy inefficient and environmentally damaging.In contrast to human-made materials, organisms synthesize composites whose intricate structures are more controlled at each scale and hierarchical order.

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