Nanoscience and Technology

The application of cross-linking resin is an effective method for improving and controlling dimensional stability, such as the shrinkage of viscose single jersey knits. However, such treatment often leads to a significant deterioration in the bursting strength of treated fabrics. In this regard, resin treatment using a softening agent can be an additional potential solution for retaining the bursting strength of treated fabrics. Resin treatment is one kind of chemical finishing process that inhibits cellulosic textile fibre swelling during wetting, provides fibre resistance to deformation and prevents shrinkage. The key objective of this study was to model the effect of resin-finishing process variables for predicting the shrinkage control and bursting strength of viscose single jersey knitted fabrics. The MATLAB (Version 8.2.0.701) fuzzy expert system was used to model the optimum resin and softener concentrations, as well as the best curing time for the prediction of maximum shrinkage control with a minimum loss in fabric bursting strength. The optimal process variables were found to be a resin concentration of 75 g/l, a softener concentration of 45 g/l and a curing time of 225 seconds. The fuzzy expert model developed in this study was validated using experimental data. It was found that the model has the ability and accuracy to predict fabric shrinkage and bursting strength effectively in the non-linear field.

Nanoparticles are particles of size between  1nm to 100nm. They large area to volume ratio of the particles account  for chemistry of the particles and thus higher reactivity  and broader application  in the industries,  medicine  and agriculture.
Nanoparticles can be synthesized by chemical,  physical or biological means.  The synthesized particles can be characterized using  XRD,  IR,  SEM,  EDS,  TEM

The demand projected in the world's population growth emphasis the advent of new technologies in the areas of energy consumption, environmental changes, and biomedical applications which play a major part in human life. One promising technology that fulfills the above demand is nanosciences and nanotechnology which play a crucial role at the nanoscale in energy, environment, and Lifesciences. Nanosciences plays a vital role in environmental monitoring, energy conversion, distribution, and storage as well as useful in gene therapy, drug delivery systems, and tissue engineering. The use of nanoscale materials and nanoparticles in these arenas eases the process flow and cost-effective with ecofriendly over the current conventional methods or applications. The various applications of nanosciences and Nanobiotechnology are versatile and find their applications in the fields of human diagnostics, bioremediation, waste management, medical devices, tissue engineering, green technology, environmental monitoring, emission control, electricity production and transmission loss, solar power, etc.

The past few decades have seen the proliferation of discourses, practices, and spaces of what has come to be termed ‘art-science’. Employed in the social sciences as a loose umbrella term for a heterogeneous array of practices, art-science is typically seen to be united by a common attempt to explore and open up the liminal space between the methods, knowledges, and objects of these increasingly bifurcated disciplines. Pushing beyond the representational logic of interdisciplinary ‘communication’ that continues to frame social science engagements, this paper instead explores the implications of the philosophy of Alfred North Whitehead for how we might rethink art-science as a space of ontological encounter that opens a creative interval in disciplinary habits of thought that transforms how the world appears. What Whitehead offers is an understanding of art and science as modes of thought which can enhance capacities to be affected by material relations and nonhuman forces in ways that orient thinking and perception towards other possible individuations. In particular, I foreground the concept of ‘abstraction’ as an important conceptual frame through which to rethink art-science encounters as ethical interventions in worlds of process that produce empirically-felt variations in the way experience comes to matter (Stengers, 2008). I flesh this out through an engagement with the Bristol-based nanoart collective danceroom Spectroscopy whose installations, I argue, creatively engage artistic (new media and technologies of visualisation; contemporary dance), scientific (the speculative concepts of the nanoscale and molecular fields), and corporeal (the intensities and forces of dancing bodies) techniques of abstraction in ways that modify our capacities for thinking and feeling the immanent forces and nonhuman agencies of emergent (nano-) worlds.

Electron Beam Lithography (EBL) is a fundamental technique of nanofabrication, allowing not only the direct writing of structures down to sub-10 nm dimensions, but also enabling high volume nanoscale patterning technologies such as (DUV and EUV) optical lithography and nanoimprint lithography through the formation of masks and templates. This chapter summarizes the key principles of EBL and explores some of the complex interactions between relevant parameters and their effects on the quality of the resulting lithographic structures. The use of low energy exposure and cold development is discussed, along with their impacts on processing windows. Applications of EBL are explored for the fabrication of very small isolated bridge structures and for high density master masks for nanoimprint lithography. Strategies for using both positive and negative tone resists are explored.

Tribofilms are activated using precision sliding strip microscale tribometry with a base and a fully formulated lubricant with a ZDDP anti-wear additive. The employed tribometry uses combined pressure, shear and temperature activation. The chemical compositions of the formed tribofilms are ascertained through use of Photo-electron X-ray Spectroscopy (XPS). Nanoscale frictional measurements of the tribofilms are reported using fluid cell lateral force microscopy (LFM). The measured coefficient of interfacial boundary shear strength is used with analytical contact mechanics to relate the in-situ conditions to the activation energy components of the Eyring potential cage model. The paper shows that combined LFM and the Eyring model can explain the variations in the frictional characteristics of formed tribofilms.

"This invention relates to methods for bonding substrates, and in particular, bonding of semiconductor and/or semiconductor oxide and nitride wafers.

Abstract: Substrates may be bonded according to a method comprising contacting a first bonding surface of a first substrate with a second bonding surface of a second substrate to form an assembly; and compressing the assembly in the presence of an oxidizing atmosphere under suitable conditions to form a bonding layer between the first and second surfaces, wherein the first bonding surface comprises a polarized surface layer; the second bonding surface comprises a hydrophilic surface layer; the first and second bonding surfaces are different. ...

BACKGROUND

The long-term reliability of multicomponent devices such as bio-sensors and solar cells is at least in part determined by the robustness of the bonding methods used to hold the devices together. Typically, epoxy bonding methods are used to prepare such devices, but suffer from the limitations of limited longevity (10 years) as well as poor thermal matching between components which can lead to internal stresses and ultimately bonding failure. Implantable bio-sensor devices need to be hermetically sealed in a saline environment such as a human or an animal body for the lifetime of the implant.

As many biosensors and solar cells are typically based on silica wafers (borosilicate, alpha-quartz, etc.) and Si(100) wafers, there exists a need in the art for improved methods for bonding the same together. In particular, there exists a need for methods which can provide hermetically sealed devices which may be implanted into the human body. Additionally, there exist needs to improve the temperature and pressure requirements of bonding for such applications. There is also a need to improve the bonding between a broader range of materials for such applications.

SUMMARY

OF THE INVENTION
Accordingly, in a first aspect, the invention provides methods for bonding substrates comprising contacting a first surface of a first substrate with a second surface of a second substrate to form an assembly; and compressing the assembly in the presence of an oxidizing atmosphere under suitable conditions to form a bonding layer between the first and second surfaces, wherein the first surface comprises a polarized surface layer; the second surface comprises a hydrophilic surface layer; the first and second surfaces are different.

In another aspect, the invention provides methods for bonding substrates comprising contacting a first bonding surface comprising O2H2Si(1×1)(100) of a first substrate comprising Si with a second bonding surface of a second substrate comprising a silicate to form an assembly; and compressing the assembly in the presence of an oxidizing atmosphere under suitable conditions to form a bonding layer between the first and second bonding surfaces.

In another aspect, the invention provides methods for bonding substrates comprising contacting a first bonding surface comprising hydroxy-terminated silica of a first substrate comprising a silicate with a second bonding surface comprising SiOx, where 0<x≦2, of a second substrate comprising a silicate to form an assembly; and compressing the assembly in the presence of an oxidizing atmosphere under suitable conditions to form a bonding layer between the first and second bonding surfaces.

In a second aspect, the invention provides the bonded substrates formed according to the first aspect of the invention.

In a third aspect, the invention provides implantable medical devices comprising a bonded substrate of the second aspect of the invention.

In a fourth aspect, the invention provides solar cells comprising a bonded substrate of the second aspect of the invention."

Os espaços laborais de manipulação e produção de nanotecnologia
criam um meio ambiente do trabalho diferenciado, pois além do risco do trabalhador/pesquisador que produz ou manipula a nova tecnologia, tem-se o
risco do trabalhador que utiliza a nova tecnologia no seu ambiente do
trabalho para a fabricação de seus derivados (sem contar o risco de toda a
cadeia produtiva que é transmitido a quem as transporta, comercializa,
consome e de quem trabalha com a destinação final tanto do produto como
do resíduo).
O presente estudo tem como objetivo verificar se os pesquisadores
percebem na sua atividade de pesquisa os possíveis riscos da produção ou
manipulação de nanotecnologias no ambiente laboral para a saúde e meio
ambiente do trabalho, bem como, apresentar diretrizes que assegurem ao
pesquisador/empregado de nanotecnologia, um meio ambiente de trabalho
saudável e com riscos controlados.
A pesquisa se justifica uma vez que o meio ambiente do trabalho,
adequado e seguro, é um dos mais importantes direitos fundamentais do
cidadão, sendo que o trabalho faz parte da vida em sociedade e todos os
trabalhadores passam mais tempo de suas vidas no ambiente laboral e
desenvolvendo tarefas, do que em convívio de lazer com seus familiares.
Considerando que o tempo desempenhando atividades laborais é de cerca de
08 horas diárias, caso o ambiente não seja saudável haverá agressão ao
trabalhador e em consequência a sociedade em geral.

This paper brings into attention the paradoxical nature of nano-objects and analyses the relationship between an imperceptible matter (too small to be perceived by the senses) and its forms of sensible manifestation.

The development of nano-sciences and nano-technologies would have not been possible without the invention of a number of visualisation instruments (like the STM – Scanning Tunnelling Microscope and the AFM – Atomic Force Microscope). From this perspective, we can speak of nano-particles as “image-objects” (Sacha Loeve), as a mediated matter. If there are a series of research projects related to the nature of epistemological inquiry in the field of nano-sciences and nano-technologies, there are still a few concerns related to the changes that occur in the field of aesthetics when it comes to the apprehension of nano-technologically treated materials.

By taking into account the latest developments in the field of nano-technologies applied to textiles, the present paper examines the way the status and the significance of materials change when they are nano-technologically treated. In order to do so, we propose a fictional scenario related to some of Joseph Beuys’ works in which we replace the “traditional” fabrics used by the artist with new ones, nano-technologically produced or treated. By using Joseph Beuys’s artistic approach as a methodological tool of critical enquiry, we are looking to the ways the perceptive, epistemological and semiotic categories are to be re-evaluated when related to nano-technological approaches. The analysis will help to formulate some of the issues artists, designers and researchers should consider when dealing with what we call the “aesthetics of imperceptibility” of nano-materials and nano-technologies.

Iron oxide (β-Fe2O3) nanoparticles were synthesized through a biological method using earthworm based extracts like Eudrilus eugineae vermiwash, Eisenia fetida vermiwash, Eudrilus eugineae crushed extract, Eisenia fetida crushed extract, Eudrilus eugineae warm water extract, Eisenia fetida warm water extract and cow dung extract as a reducing and stabilizing agents. The development of β-Fe2O3 nanoparticles in the reaction mixture was determined by UV–visible spectroscopy. Followed by, the synthesized β-Fe2O3 nanoparticles were characterized by X-ray diffraction, Fourier transforms infra–red spectroscopy, scanning electron microscopy, and energy dispersive X-ray and transmission electron microscopy. Synthesized β-Fe2O3 NPs are characterized as crystalline structure of hexagonal shape with particle size of 2.08-94.37 nm and carrying unique functional groups. Bioefficiency of β-Fe2O3 was assessed through In-vitro seed germination study with green gram (Vigna radiata) and results reveal...

Nauclea latifolia is one of the medicinal plants used in traditional Nigerian medicine in the treatment of various diseases such as fever, toothaches, malaria, diarrhea among several other conditions. Nauclea latifolia leaf extract acts as a capping and reducing agent in the formation of silver nanoparticles. Silver nanoparticles (AgNPs) were synthesized using a combination of aqueous extract of Nauclea latifolia and 1mM of silver nitrate (AgNO3) solution to obtain concentrations of 100mg/ml-400mg/ml. Characterization of the particles was done by UV-Vis spectroscopy and Fourier transform infrared (FTIR). In this study, aqueous as well as ethanolic extract of leaf of Nauclea latifolia were investigated for antibacterial activity using the standard agar well diffusion technique against three clinical isolates (Escherichia coli, Staphylococcus aureus, and Pseudomonas aeruginosa). The Minimum Inhibitory Concentration (MIC) was achieved by microbroth dilution method and Minimum Bactericidal Concentration (MBC) was also determined by plate assay. Characterization by UV-visible spectrometry revealed peak absorbance of 0.463 at 450.0nm, while FTIR showed the presence of two functional groups. At 400mg/ml, the highest inhibitory activities were observed with S.aureus and E.coli with zones of inhibition measuring 20mm and 18mm respectively. The MIC was obtained at 400mg/ml while MBC was at a higher concentrations. The data from this study indicates the potential of silver nanoparticle of Nauclea latifolia as a suitable alternative antibacterial agent for incorporation into orthodox medicine in health care delivery in Nigeria.

Context: Nanostructured lipid carriers can enhance skin penetration of active substances. Coenzyme Q10 is a lipophilic antioxidant, that has poor skin penetration. This limitation is overcome by nanostructured lipid carriers.

Aims: To developed coenzyme Q10 nanostructured lipid carriers using myristic acid with various liquid lipids as lipid matrix by in vitro studies and in silico approach for explaining the interaction of coenzyme Q10-lipid at the molecular level.

Methods: The coenzyme Q10 nanostructured lipid carriers were prepared using myristic acid as solid lipid with oleic acid, isopropyl myristate, and isopropyl palmitate as liquid lipids using the high shear homogenization method. Then, they were evaluated in physicochemical characteristics by dynamic light scattering, differential scanning calorimetry, Fourier transforms infrared, scanning electron microscopy, spectrophotometry ultraviolet-visible, and pH meter. Furthermore, the in silico studies were conducted using AutoDock 4.2.

Results: The coenzyme Q10 nanostructured lipid carriers using myristic acid-oleic acid, myristic acid-isopropyl myristate, and myristic acid-isopropyl palmitate as lipid matrix had the mean particle size, polydispersity index, entrapment efficiency, drug loading, and pH value were less than 300 nm, less than 0.3, more than 80%, about 10%, and about 5.0, respectively. Moreover, molecular docking of coenzyme Q10 and lipid showed hydrogen and hydrophobic bonds. These results supported differential scanning calorimetry and Fourier transforms infrared results.

Conclusions: The coenzyme Q10 nanostructured lipid carriers were successfully prepared using myristic acid-oleic acid, myristic acid-isopropyl myristate, and myristic acid-isopropyl palmitate as lipid matrix as well as in silico study could be used for explaining of coenzyme Q10-lipid interaction.