scholarly journals Impact of Titanium Dioxide (TiO2) Modification on Its Application to Pollution Treatment—A Review

Catalysts ◽  
2020 ◽  
Vol 10 (7) ◽  
pp. 804 ◽  
Author(s):  
Ruixiang Li ◽  
Tian Li ◽  
Qixing Zhou
Keyword(s):  
Titanium Dioxide ◽  
Photocatalytic Oxidation ◽  
High Efficiency ◽  
Chemical Properties ◽  
Treatment Method ◽  
Catalytic Performance ◽  
Pure Tio2 ◽  
Inorganic Substances ◽  
Recent Developments ◽  
Physical And Chemical

A high-efficiency method to deal with pollutants must be found because environmental problems are becoming more serious. Photocatalytic oxidation technology as the environmentally-friendly treatment method can completely oxidate organic pollutants into pollution-free small-molecule inorganic substances without causing secondary pollution. As a widely used photocatalyst, titanium dioxide (TiO2) can greatly improve the degradation efficiency of pollutants, but several problems are noted in its practical application. TiO2 modified by different materials has received extensive attention in the field of photocatalysis because of its excellent physical and chemical properties compared with pure TiO2. In this review, we discuss the use of different materials for TiO2 modification, highlighting recent developments in the synthesis and application of TiO2 composites using different materials. Materials discussed in the article can be divided into nonmetallic and metallic. Mechanisms of how to improve catalytic performance of TiO2 after modification are discussed, and the future development of modified TiO2 is prospected.

scholarly journals Magnetic iron oxide/clay nanocomposites for adsorption and catalytic oxidation in water treatment applications

2020 ◽  
Vol 18 (1) ◽  
pp. 1148-1166
Author(s):  
Ganjar Fadillah ◽  
Septian Perwira Yudha ◽  
Suresh Sagadevan ◽  
Is Fatimah ◽  
Oki Muraza
Keyword(s):  
Iron Oxide ◽  
Water Treatment ◽  
Photocatalytic Oxidation ◽  
Low Cost ◽  
Synthesis Method ◽  
Chemical Oxidation ◽  
Magnetic Iron Oxide ◽  
Oxidation Processes ◽  
Recent Developments ◽  
Physical And Chemical

AbstractPhysical and chemical methods have been developed for water and wastewater treatments. Adsorption is an attractive method due to its simplicity and low cost, and it has been widely employed in industrial treatment. In advanced schemes, chemical oxidation and photocatalytic oxidation have been recognized as effective methods for wastewater-containing organic compounds. The use of magnetic iron oxide in these methods has received much attention. Magnetic iron oxide nanocomposite adsorbents have been recognized as favorable materials due to their stability, high adsorption capacities, and recoverability, compared to conventional sorbents. Magnetic iron oxide nanocomposites have also been reported to be effective in photocatalytic and chemical oxidation processes. The current review has presented recent developments in techniques using magnetic iron oxide nanocomposites for water treatment applications. The review highlights the synthesis method and compares modifications for adsorbent, photocatalytic oxidation, and chemical oxidation processes. Future prospects for the use of nanocomposites have been presented.

scholarly journals Tribology of 2D Nanomaterials: A Review

2020 ◽  
Author(s):  
Paul С. Uzoma ◽  
Huan Hu ◽  
Mahdi Khadem ◽  
Oleksiy V. Penkov
Keyword(s):  
High Performance ◽  
2D Materials ◽  
Chemical Properties ◽  
Solid Lubricants ◽  
Friction Behavior ◽  
Comprehensive Overview ◽  
Wear Rates ◽  
Recent Developments ◽  
Frictional Coefficients ◽  
Physical And Chemical

The exfoliation of graphene has opened a new frontier in material science with a focus on 2D materials. The unique thermal, physical and chemical properties of these materials have made them one of the choicest candidates in novel mechanical and nano-electronic devices. Notably, 2D materials such as graphene, MoS2, WS2, h-BN, and Black Phosphorus have shown outstanding lowest frictional coefficients and wear rates, making them attractive materials for high-performance nano-lubricants and lubricating applications. The objective of this work is to provide a comprehensive overview of the most recent developments in the tribological potentials of 2D materials. At first, the essential physical, wear, and frictional characteristics of the 2D materials including their production techniques are discussed. Subsequently, the experimental explorations and theoretical simulations of the most common 2D materials are reviewed in regards to their tribological applications such as their use as solid lubricants and surface lubricant nano-additives. The effects of micro/nano textures on friction behavior are also reviewed. Finally, the current challenges in tribological applications of 2D materials and their prospects are discussed.

Recent developments in the utility of saturated azaheterocycles in peptidomimetics

2022 ◽  
Author(s):  
Manish Kumar Singh ◽  
Mahesh K Lakshman
Keyword(s):  
Chemical Properties ◽  
Physical And Chemical Properties ◽  
Recent Developments ◽  
Physical And Chemical ◽  
And Chemical Properties

To large extent, the physical and chemical properties of peptidomimetic molecules are dictated by the integrated heterocyclic scaffolds they contain. Heterocyclic moieties are introduced into a majority of peptide-mimicking molecules...

Characteristics of Chitosan Nanoparticles for Water and Wastewater Treatment

2017 ◽  
pp. 223-261 ◽  
Author(s):  
Cayla Cook ◽  
Veera Gnaneswar Gude
Keyword(s):  
Wastewater Treatment ◽  
Chitosan Nanoparticles ◽  
Antimicrobial Properties ◽  
Chemical Properties ◽  
Water And Wastewater Treatment ◽  
Coagulation And Flocculation ◽  
Recent Developments ◽  
Water And Wastewater ◽  
Physical And Chemical

Chitosan is a naturally occurring biopolymer originating from several microbial species as well as crustacean species, such as shrimp and lobster. Chitosan has excellent physical and chemical properties that allow its use in various environmental applications especially in water treatment. It is a biodegradable polymer, and it is inexpensive providing an environmentally friendly and economic option for water and wastewater treatment. Chitosan offers a myriad of applications through chemical coagulation and flocculation, antimicrobial properties, adsorption capabilities, and nanofiltration and can provide a sustainable route for water and wastewater treatment. This book chapter elaborates the recent developments in chitosan applications in water and wastewater treatment.

scholarly journals Tribology of 2D Nanomaterials: A Review

Coatings ◽  
2020 ◽  
Vol 10 (9) ◽  
pp. 897
Author(s):  
Paul C. Uzoma ◽  
Huan Hu ◽  
Mahdi Khadem ◽  
Oleksiy V. Penkov
Keyword(s):  
High Performance ◽  
2D Materials ◽  
Chemical Properties ◽  
Solid Lubricants ◽  
Friction Behavior ◽  
Comprehensive Overview ◽  
Wear Rates ◽  
Recent Developments ◽  
Frictional Coefficients ◽  
Physical And Chemical

The exfoliation of graphene has opened a new frontier in material science with a focus on 2D materials. The unique thermal, physical and chemical properties of these materials have made them one of the choicest candidates in novel mechanical and nano-electronic devices. Notably, 2D materials such as graphene, MoS2, WS2, h-BN and black phosphorus have shown outstanding lowest frictional coefficients and wear rates, making them attractive materials for high-performance nano-lubricants and lubricating applications. The objective of this work is to provide a comprehensive overview of the most recent developments in the tribological potentials of 2D materials. At first, the essential physical, wear and frictional characteristics of the 2D materials including their production techniques are discussed. Subsequently, the experimental explorations and theoretical simulations of the most common 2D materials are reviewed in regards to their tribological applications such as their use as solid lubricants and surface lubricant nano-additives. The effects of micro/nano textures on friction behavior are also reviewed. Finally, the current challenges in tribological applications of 2D materials and their prospects are discussed.

scholarly journals The Neutral Envelopes of Planetary Nebulae: Molecules and H I

1993 ◽  
Vol 155 ◽  
pp. 147-154 ◽  
Author(s):  
P.J. Huggins
Keyword(s):  
Chemical Properties ◽  
Planetary Nebulae ◽  
Physical And Chemical Properties ◽  
Agb Stars ◽  
Subsequent Evolution ◽  
Neutral Gas ◽  
Recent Developments ◽  
Molecular Lines ◽  
Physical And Chemical ◽  
And Chemical Properties

This paper summarizes recent developments in the study of planetary nebulae using observations of molecular lines and the 21 cm line of H I. The observations reveal that many planetary nebulae are surrounded by envelopes of neutral gas, whose mass often exceeds that of the ionized nebulae. They also provide valuable information on the physical and chemical properties of the envelopes, their structure, and kinematics. The neutral envelopes firmly link the formation of planetary nebulae with the mass loss by AGB stars, and can play an important role in the subsequent evolution of the nebulae.

scholarly journals Review on Acoustic Droplet Vaporization in Ultrasound Diagnostics and Therapeutics

2019 ◽  
Vol 2019 ◽  
pp. 1-20
Author(s):  
Ksenia Loskutova ◽  
Dmitry Grishenkov ◽  
Morteza Ghorbani
Keyword(s):  
Surrounding Medium ◽  
Chemical Properties ◽  
General Idea ◽  
Pressure Amplitude ◽  
Acoustic Droplet Vaporization ◽  
New Techniques ◽  
Droplet Vaporization ◽  
Ultrasound Diagnostics ◽  
Recent Developments ◽  
Physical And Chemical

Acoustic droplet vaporization (ADV) is the physical process in which liquid undergoes phase transition to gas after exposure to a pressure amplitude above a certain threshold. In recent years, new techniques in ultrasound diagnostics and therapeutics have been developed which utilize microformulations with various physical and chemical properties. The purpose of this review is to give the reader a general idea on how ADV can be implemented for the existing biomedical applications of droplet vaporization. In this regard, the recent developments in ultrasound therapy which shed light on the ADV are considered. Modern designs of capsules and nanodroplets (NDs) are shown, and the material choices and their implications for function are discussed. The influence of the physical properties of the induced acoustic field, the surrounding medium, and thermophysical effects on the vaporization are presented. Lastly, current challenges and potential future applications towards the implementation of the therapeutic droplets are discussed.

The reliability of radiocarbon dates of different carbon fractions in the Australian tropical savannas: A case study from Sanamere Lagoon, northeast Australia

2020 ◽  
Author(s):  
Maria Rivera-Araya ◽  
Michael Bird ◽  
Cassandra Rowe ◽  
Sean Ulm ◽  
Vladimir Levchenko
Keyword(s):  
Chemical Properties ◽  
Treatment Method ◽  
Tropical Lake ◽  
Tropical Lakes ◽  
Radiocarbon Dates ◽  
Carbon Fractions ◽  
Polycyclic Aromatic ◽  
Organic Fractions ◽  
Pre Treatment ◽  
Physical And Chemical

<p>The selection and pre-treatment of a reliable organic fraction from which to acquire radiocarbon dates is fundamental to obtain accurate chronologies. Sampling from tropical lakes is particularly challenging given the adverse preservation conditions and diagenesis in these environments. Our research is the first to examine and quantify the differences between the radiocarbon date results from different carbon fractions and pretreatments from the same depths from a tropical lake sediment core (1.72 m long) located in north Australia to assess which one(s) are more reliable. Six different organic fractions (bulk organics, pollen concentrate, cellulose, stable polycyclic aromatic carbon (SPAC), charcoal >250 um and charcoal >63 um), for a total of 27 radiocarbon dates, were compared in six different depths along the core. Acid-base-acid (ABA), modified ABA (30 % hydrogen peroxide + ABA), 2chlorOx (a novel cellulose pre-treatment method) and hydrogen pyrolysis (hypy) were used to pre-treat the correspondent organic fractions. The oldest date is 31,295 calibrated years before present (cal yr BP) and the youngest is 2,048 cal yr BP, spanning 29,247 years. The smallest offset between the minimum and the maximum age in a given depth was found to be 975 years (between SPAC and charcoal >63 um) and the largest 16,527 years (between pollen concentrate and SPAC). The SPAC fractions pre-treated with hypy consistently yielded older ages compared to all other fraction in most cases, while bulk organics yielded consistently younger ones. The magnitude and consistency of the offsets and the physical and chemical properties of the tested organic fractions suggest that SPAC is the most reliable fraction to date in tropical lake sediments and that hypy successfully removes contamination sourced from exogenous carbon.</p>

scholarly journals Synthesis of Silica Nanoparticles by Sol-Gel: Size-Dependent Properties, Surface Modification, and Applications in Silica-Polymer Nanocomposites—A Review

2012 ◽  
Vol 2012 ◽  
pp. 1-15 ◽  
Author(s):  
Ismail Ab Rahman ◽  
Vejayakumaran Padavettan
Keyword(s):  
Surface Modification ◽  
Silica Nanoparticles ◽  
Polymer Nanocomposites ◽  
Sol Gel ◽  
Chemical Properties ◽  
Size Dependent ◽  
Recent Developments ◽  
Gel Technique ◽  
Nanoparticles Characterization ◽  
Physical And Chemical

Application of silica nanoparticles as fillers in the preparation of nanocomposite of polymers has drawn much attention, due to the increased demand for new materials with improved thermal, mechanical, physical, and chemical properties. Recent developments in the synthesis of monodispersed, narrow-size distribution of nanoparticles by sol-gel method provide significant boost to development of silica-polymer nanocomposites. This paper is written by emphasizing on the synthesis of silica nanoparticles, characterization on size-dependent properties, and surface modification for the preparation of homogeneous nanocomposites, generally by sol-gel technique. The effect of nanosilica on the properties of various types of silica-polymer composites is also summarized.

Sign in / Sign up

Export Citation Format

Share Document