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The main purpose of taking up this work was to see the influence of metallic nanoparticles on various fabric properties. This paper emphasizes on mechanical, aesthetic and anti-bacterial properties of the polyester, cotton and polyester cotton-blended fabric samples.

Three fabrics, 100 per cent polyester, 100 per cent cotton and polyester cotton-blended (50:50), were procured from the market. They were subjected to mild washing treatment so that the fabrics could be impregnated with copper (Cu) nanoparticles following standard procedure. The characterization of Cu nano-loaded textiles has been done using various techniques such as scanning electron microscopy for surface morphology, X-ray fluorescence spectrometer for elemental analysis and Fourier transform infrared spectroscopy for chemical composition. However in this paper, the focus is on various fabric properties and influence of this treatment on them. Antimicrobial activity was measured as per AATCC 100 quantitative method.

The structural properties showed changes but not major ones. The impregnation of Cu nanoparticles is nothing but a chemical treatment, and it is not uncommon to find reduction in the mechanical properties of the specimen. Here also, the mechanical properties were studied but did not reveal any significant change. The aesthetic properties for cotton fabrics showed an improvement. Improvement in the anti-bacterial activity was observed for all the fabric samples but the improvement in cotton fabric is worth mentioning. Thus, nano treatment imparts anti-bacterial property without hampering the mechanical properties of the parent textiles.

It is usual to find changes in the various properties of the materials subjected to nano treatment or treatment of any sort. Though the fabric samples were subjected to similar treatment, the quantity of nanoparticles taken up by each of them was different. The reason behind this could be the difference in the crystallinity of the fabric samples. Polyester fabric showed the highest resistance, as it was least affected by the nano treatment given. Cotton fabrics composed of cotton fibers are amorphous in nature, hence showed better take-up and hence were more affected by the said treatment.

Cotton fabrics are the most favored fabric, especially in regions with hot climatic conditions. Even though these fabrics are very sought after, they have a major drawback related to the aesthetic appeal of the fabric. These fabrics have very poor resistance to the crease formation, as well as their ability to recover from the external deformation. But the study conducted on the fabric samples has shown favorable results for the cotton fabric. A significant improvement in their aesthetic and anti-bacterial activity was found. At present, textiles with nano finishing fall in niche market due to its higher cost. But finishing with in-house Cu nanoparticles may open up hygiene textiles for consumers at affordable rates.

Cotton is still the most popular natural fiber in most of the tropical and sub-tropical regions. People located in these places have a natural urge to wear fabrics made from cotton fibers. Due to the hot weather, sweating is natural. However, this tends to keep the skin in humid state resulting in various skin problems, as cotton is also prone to bacterial attack. But this work has shown positive results, meaning to say that cotton fabrics show improved resistance to the bacterial activity. Hence, its suitability for hygiene applications may soon become a reality.

It is true that a lot of work is being reported on nano materials and their application to textiles for various reasons. Recently, many reports are available related to finishing of textiles using nanoparticles. However, most of the researchers are using silver nanoparticles for the same. In this work, use of in-house Cu nanoparticles has been done to treat fabric samples, which is more economical than silver nano. Also quantity required to meet desired property with Cu nanoparticles is less than the conventional treatment. This work is a sincere attempt to prepare hygienic common textiles at economical rates using continuous application technique which offers durable efficacy against human pathogenic bacterium.

This work aimed to prepare black transition metal oxide pigments to be used as solar absorbers in the solar selective and other industrial paints.

Mixed metal oxide CoCuMnO_x spinel pigments were synthesised via the sol‐gel route. These oxides, namely (I‐Co_0.50Cu_0.25Mn_0.25)O_x, (II‐Co_0.25Cu_0.50Mn_0.25)O_x and (III‐Co_0.25Cu_0.25Mn_0.50)O_x, were prepared with different molar ratios and annealed at 600, 800 and 900°C, respectively. The prepared oxides were characterised by infrared spectrometer (IS), differential scanning calorimetry analysis (DSC), X‐ray diffraction (XRD) and transmission electron microscope (TEM).

The prepared pigments have a spinel structure with the composition CoCuMnO_x. All synthesised pigments consisted of nano particles ranged from 10 to 80 nm. The optical properties showed high absorption and moderately low reflectance in the solar wavelength range.

The prepared samples, used in the present work, were synthesized from cobalt sulphate, copper chloride and manganese chloride. The salts were dispersed in polyacrylamide as a precursor.

The prepared samples were thermally stable and had good optical properties. They could be used as absorber materials in the painting of solar collectors.

These thermally stable mixed metal oxides could be used in the painting of solar collectors. The three mixed metal oxides could be used as absorber materials for heating solar collectors due to their high absorption and moderately low reflectance in the solar wavelength range.

Nanotechnology is nowadays very much successful in producing specifically functionalized nano-sized particles. In this work, copper nanoparticles were prepared by reduction method which is greener and environmentally suitable, cheap and best as compared to other conventional methods, particularly in the context of COVID in globalized world. The formation and size of copper nanoparticles was evidenced by the X-ray diffraction and transmission electron microscopy. The very high surface area of 35–50 m²/gm and very small crystallite sizes of 5–15 nm of these metal nanoparticles is mainly responsible for their effective involvement in removal of carbon dioxide gas as one of major hazardous pollutants from the environment. This chapter, as its main objective, mainly focuses on utility of nano technology and its beneficiary in creating a sustainable environment in economic world. Apart from laboratory experimental procedure and characterizations for preparation of copper nanoparticles, appropriate research methods such as simple statistical, econometric tools and mathematical tools have been used for economic analysis. However, as major findings of the results, developed countries have been successful in maintaining a sustainable human development, in spite of having higher per capita income (PCI) growth as compared to the role of developing countries with lower PCI in this global world.

This review deals with the pros and cons of ultraviolet (UV) radiation on human beings and the role of textile clothing and the chemicals used for textiles to protect from their harmful effects.

UV radiation (UVR) which has further divided into UVA, UVB, and UVC. Almost 100% of UVC and major portion of UVB are bounced back to stratosphere by ozone layer while UVA enters the earth atmosphere. Excessive exposure of solar or artificial UVR exhibit potential risks to human health. UVR is a major carcinogen and excessive exposure of solar radiation in sunlight can cause cancer in the lip, skin squamous cell, basal cell and cutaneous melanoma, particularly in people with the fair skin.

This article aims to provide a comprehensive overview of the harmful effects of UVR on human skin, factors affecting UV irradiance and factors affecting UV protection offered by textile clothing.

Effect of fiber properties, yarn properties, fabric construction, fabric treatments and laundering has been reviewed along with the identification of gaps in the reported research. A comparison of inorganic and organic UV absorbers has also been given along with different testing and evaluation methods for UV protective clothing.

Material formulation, structuring and modification are key to increasing the unit volume complexity and density of next generation electronic packaging products. Laser processing is finding an increasing number of applications in the fabrication of these advanced microelectronic devices. The purpose of this paper is to discuss the development of new laser‐processing capabilities involving the synthesis and optimization of materials for tunable device applications.

The paper focuses on the application of laser processing to two specific material areas, namely thin films and nanocomposite films. The examples include BaTiO₃‐based thin films and BaTiO₃ polymer‐based nanocomposites.

A variety of new regular and random 3D surface patterns are highlighted. A frequency‐tripled Nd:YAG laser operating at a wavelength of 355 nm is used for the micromachining study. The micromachining is used to make various patterned surface morphologies. Depending on the laser fluence used, one can form a “wavy,” random 3D structure, or an array of regular 3D patterns. Furthermore, the laser was used to generate free‐standing nano and micro particles from thin film surfaces. In the case of BaTiO₃ polymer‐based nanocomposites, micromachining is used to generate arrays of variable‐thickness capacitors. The resultant thickness of the capacitors depends on the number of laser pulses applied. Micromachining is also used to make long, deep, multiple channels in capacitance layers. When these channels are filled with metal, the spacings between two metallized channels acted as individual vertical capacitors, and parallel connection eventually produce vertical multilayer capacitors. For a given volume of capacitor material, theoretical capacitance calculations are made for variable channel widths and spacings. For comparison, calculations are also made for a “normal” capacitor, that is, a horizontal capacitor having a single pair of electrodes.

This technique can be used to prepare capacitors of various thicknesses from the same capacitance layer, and ultimately can produce variable capacitance density, or a library of capacitors. The process is also capable of making vertical 3D multilayer embedded capacitors from a single capacitance layer. The capacitance benefit of the vertical multilayer capacitors is more pronounced for thicker capacitance layers. The application of a laser processing approach can greatly enhance the utility and optimization of new materials and the devices formed from them.

Laser micromaching technology is developed to fabricate several new structures. It is possible to synthesize nano and micro particles from thin film surfaces. Laser micromachining can produce a variety of random, as well as regular, 3D patterns. As the demand grows for complex multifunctional embedded components for advanced organic packaging, laser micromachining will continue to provide unique opportunities.

The purpose of this paper is to propose a new method of synthesis of CuO · SiO₂ oxide composite based on the reaction of precipitation from water solutions of sodium silicate and copper nitrate.

Solutions of sodium silicate and copper nitrate were used as substrates. The effects of direction of substrate supply, concentration, excess of reagents and temperature of precipitation on the physicochemical properties of the products were analysed.

A new method of synthesis of CuO · SiO₂ oxide composite based on a precipitation reaction is proposed.

Only sodium silicate and copper nitrate solutions were used.

The CuO · SiO₂ oxide composite obtained can be used as blue pigment or polymer filler.

The paper determines optimum conditions of CuO · SiO₂ oxide composite precipitation to obtain products with desired physicochemical, dispersive and structural properties.

This paper aims to examine the investigations made on the corrosion behaviour of magnesium (Mg) substrate electrodeposited using different nano-materials.

This study uses nano-materials such as those of reduced graphene oxide (r-GO), titanium-di-oxide (TiO₂) and also r-GO/TiO₂ nano-composites (dispersed through ultra-sonication process) at 3-min time interval. Crystalline nature of synthesized TiO₂ is studied through X-ray diffraction and its pore volume is measured to be approximately 0.1851ccg-1 by Brunauer Emmett Teller analysis.

Surface morphology of the developed set of specimens inspected through scanning electron microscopy and energy dispersive spectroscopy establishes a clean surface coating and further witnesses for only minimal defects. Electrochemical behaviour of the developed coating is studied exhaustively using Tafel polarization and electrochemical impedance spectroscopy in 0.1 M Na₂SO₄ solution.

Incremental corrosion resistance exhibited by developed composite coating owes to the factors viz. chemical stability and hydrophobic tendency of TiO₂ and r-GO; these known engineering facts resist the flow of ions into the corrosive media and thereby reduce the rate of corrosion.

In the developing field of nano-materials synthesis, copper oxide nanoparticles (NPs) are deemed to be one of the most significant transition metal oxides because of their intriguing characteristics. Its synthesis employing green chemistry principles has become a key source for next-generation antibiotics attributed to its features such as environmental friendliness, ease of use and affordability. Because they are more environmentally benign, plants have been employed to create metallic NPs. These plant extracts serve as capping, stabilising or hydrolytic agents and enable a regulated synthesis as well.

Organic chemical solvents are harmful and entail intense conditions during nanoparticle synthesis. The copper oxide NPs (CuO-NPs) synthesised by employing the green chemistry principle showed potential antitumor properties. Green synthesised CuO-NPs are regarded to be a strong contender for applications in the pharmacological, biomedical and environmental fields.

The aim of this study is to evaluate the anticancer potential of CuO-NPs plant extracts to isolate and characterise the active anticancer principles as well as to yield more effective, affordable, and safer cancer therapies.

This review article highlights the copper oxide nanoparticle's biomedical applications such as anticancer, antimicrobial, dental and drug delivery properties, future research perspectives and direction are also discussed.

This contribution aims to introduce an effective low cost polymer-nanocomposite for possible application to achieve a super protection for highly damaged ancient Egyptian wall paintings.

SiO2 and Al2O3 nanoparticles were synthesized by the sol-gel method. Then, the polymer-nanocomposite was prepared by simple mixing and dispersing the nanoparticles into the tetraethoxysilane polymer solution, with the aid of an ultrasonic dismembrator. The application of the polymer-nanocomposite and other polymeric nanodispersions, on laboratory models, was performed by the brushing technique. Next, the materials stability was evaluated by means of digital optical microscope, colorimetry, FE-scanning electron microscope, measuring the static contact angle and water absorption rates.

The results were promising in creating a superhydrophobicity and the static contact angle (?S) measured for the polymer-nanocomposite reached 135o. An average of three measurements of the water absorption rate after polymer-nanocomposite treatment was 0.66 g/m2 s, compared to 2.60 g/m2 s for the control model (untreated). Further, an average of color difference (?E*) for the treated surface was 2.78, and after the accelerated thermal aging was 3.6. Observing the surface morphology, the polymer-nanocomposite enhanced the roughness of the treated surface and showed a high resistance to laboratory salt weathering.

Preparation of a polymer-nanocomposite by adding SiO2 and Al2O3 NPs to tetraethoxysilane polymer has been proposed. As a promising conservation material, the produced polymer-nanocomposite helped to form an efficient protective film.

This paper attains to develop an economic polymer-nanocomposite to maintain a high protection to damaged ancient Egyptian wall paintings and similar objects.

Among various metal oxide nano particles, MgO NPs and ZnO nanoparticles (NPs) in particular are gaining increasing attention due to their multifunctional characteristics, low cost and compatibility with textile materials. Each type of nanoparticle excels over others in certain properties. As such, it is often crucial to carry out comparative studies of NPs to identify the one showing higher efficiency/output for particular applications of textile products.

In the investigation reported in this paper, ZnO NPs and MgO NPs were synthesised via sol-gel technique and characterised. For comparative analysis, the synthesised NPs were evaluated for multiple properties using standard procedures before and after being applied on cotton fabrics by a dip-pad-dry-cure method.

XRD and FTIR analyses confirmed the successful synthesis of ZnO and MgO NPs. Homogeneous formation of desired NPs and their dense and uniform deposition on the cotton fibre surface were observed using SEM. ZnO NPs and MgO NPs coatings on cotton were observed to significantly enhance self-cleaning/stain removal properties achieving Grade 5 and Grade 4 categories, respectively. In terms of ultraviolet (UV) protection, ZnO or MgO NP coated fabrics showed UPF values of greater than 50, i.e. excellent in blocking UV rays. MgO NPs exhibited 20% cleaning efficiency in treating reactive dye wastewater against ZnO NPs which were 4% efficient in the same treatment, so MgO was more suitable for such type of treatments at low cost. Both NPs were able to impart multifunctionality to cotton fabrics as per requirement of the end products. However, ZnO NPs were better for stain removal from the fabrics while MgO NPs were appropriate for UV blocking.

It was therefore clear that multifunctional textile products could be developed by employing a single type of cost effective and efficient nano particles.