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International audience; We present first fiber Bragg grating (FBG) inscribed in polarization maintaining (PM) optical fiber with artificially anisotropic core achieved by an appropriate distribution of discrete germanium-doped areas in nanoscale. We proved that this FBG reveals unique properties. Its single-resonance spectral shape, strain and temperature sensitivities are similar to that for grating written in cylindrically symmetrical optical fiber, which indicates that it behaves as the grating fabricated in a non-PM fiber, whereas it is written in the fiber that preserves the orthogonal polarization components of the mode. Moreover, due to the relatively low birefringence of the fiber, the FBG is insensitive to the excited polarization state and twist, and only a negligible shift of the spectrum is noticeable with no changes in its shape. Thus, FBG inscribed in ZEBRA fiber is a kind of hybrid structure that can be used for all-fiber lasers that generate polarized wave, as well as for polarization fiber sensors and components with spectral insensitivity to random or intentional twist.

The broad properties of nanostructured materials based on transition metal oxides have received great attention from researchers. Copper (II) Oxide (CuO) due to its excellent physical and chemical properties, has numerous potential applications. Among the different methods previously reported to prepare CuO nanoparticles (CuO NPs) such as sonochemical, sol-gel, and electrochemical techniques, this study proposes an easeful, simple, and cost-effective method to synthesize CuO NPs by thermal decomposition of a coordination complex i.e., a binuclear copper (II) carboxylate complex.

SnO2 has been extensively used in the detection of various gases. As a gas sensing material, SnO2 has excellent physical-chemical properties, high reliability, and short adsorption-desorption time. The application of the traditional SnO2 gas sensor is limited due to its higher work-temperature, low gas response, and poor selectivity. Nanomaterials can significantly impact gas-sensitive properties due to the quantum size, surface, and small size effects of nanomaterials. By applying nanotechnology to the preparation of SnO2, the SnO2 nanomaterial-based sensors could show better performance, which greatly expands the application of SnO2 gas sensors. In this review, the preparation method of the SnO2 nanostructure, the types of gas detected, and the improvements of SnO2 gas-sensing performances via elemental modification are introduced as well as the future development of SnO2 is discussed.

We compare microstructure formation during laser powder bed fusion (LPBF) of a Ti-22Al-25Nb alloy applying low and high pre-heating build plate temperatures. Fast cooling rates during low-temperature LPBF lead to metastable weakly ordered ß phase, i.e., bcc–(Ti,Al,Nb) with pronounced texture in build direction and nanosized segregations within grains elongated in the build direction. For high-temperature LPBF a Widmanstätten microstructure was observed with lenticular O phase precipitates within the ß matrix. Microscopical and in situ high-energy synchrotron diffraction investigations demonstrate that the microstructure formation can be widely explained by the precipitation of O phase from supersaturated ß rather than by a sequence of solid-state phase transformations, as it would be expected under thermodynamic equilibrium conditions. A detailed analysis of the microstructural gradient in the subsurface region, however, demonstrates that precipitation from metastable ß cannot fully explain the observed microstructures, and that the process energy density, i.e., the intensity of the intrinsic heat treatment of LPBF, plays a relevant role. The investigation of the graded area near the surface of the LPBF materials produced with high pre-heating temperature is particularly interesting as it reveals preferred nucleation of the O phase at subgrain boundaries and dislocations.

Predictive monitoring of two key properties of nanocellulose, aspect ratio and yield of nanofibrillation, would help manufacturers control and optimize production processes, given the uncertainty that still surrounds their influential factors. For that, 20 different types of cellulosic and lignocellulosic micro/nanofibers produced from spruce and pine softwoods, and by different pre-treatment and fibrillation techniques, were used as training and testing datasets aiming at the development and evaluation of three machine learning models. The models used were Random Forests (RF), Linear Regression (LR) and Artificial Neural Networks (ANN), broadening the scope of our previous work (Santos et al. in Cellulose 29:5609–5622, 2022. https://doi.org/10.1007/s10570-022-04631-5). Performance of these models were evaluated by comparing statistical parameters such as Mean Absolute Percentage Error (MAPE) and R². For the aspect ratio and the yield of nanofibrillation, inputs were chosen among these easily controlled or measured variables: Total lignin (wt%), Cellulose (wt%), Hemicellulose (wt%), Extractives (wt%), HPH Energy Consumption (kWh/kg), Cationic Demand (µeq/g), Transmittance at 600 nm and Consistency index (Ostwald-De Waele’s k). In both cases, the ANN models trained here provided satisfactory estimates of aspect ratio (MAPE = 4.54% and R2 = 0.96) and the yield of nanofibrillation (MAPE = 6.74% and R2 = 0.98), being able to capture the effect of the applied energy along the fibrillation process. RF and LR models resulted in correlation coefficients of 0.93 and 0.95, respectively, for aspect ratio, while for yield of nanofibrillation the correlation coefficients were 0.87 and 0.92. The present work has been funded by the Spanish Ministry of Science and Innovation, projects CON-FUTURO-ES (PID2020-113850RBC22) and VALORCON-NC (PDC2021-120964-C22). Alexandre Ferreira Santos received funding from the Conselho Nacional de Desenvolvimento Científco e Tecnológico (CNPq, Brazil) for his research stay at University of Girona. The Human Resources Program of the National Agency of Petroleum, Natural Gas and Biofuels (PRH-ANP/Finep) from Brazil has economically supported the grant of Giovana S. Iamin. Open Access funding provided thanks to the CRUE-CSIC agreement with Springer Nature.

The problem of contact deformation of an elastic body loaded by gravitational forces and laying on several small rigid supports is considered in the framework of the linear theory of elasticity. Using the method of matched asymptotic expansions, the limit asymptotic model for determining the support reactions and the kinematic parameters of the body settling is derived. The effect of the body surface reinforcement is discussed. The case of a uniform (symmetric) settling is considered in detail.

[eng] The main objective of this dissertation has been to stablish a bridge between materials science and its fields of application. The scope of this thesis work, under this premise, is aimed towards understanding the catalytical properties of CeO2 nanocrystals and the applications arising from them. In order to tackle it, the chemist labour consists in providing a cutting-edge nanosynthesis technology able to improve efficiencies of the chemical processes, reducing energy consumption and minimizing the environmental impact of both activity and waste products. At the same time, research on nanomaterial synthesis involves the design and formulation of nanomaterials under total control of their physicochemical, morphological, and colloidal properties. Coupled with the appropriate description of the structure-activity relations, the current aim of nanomaterial synthesis is an application-oriented design strategy towards programmable properties of the products. Within this framework, this thesis work is divided into two parts. The first part revolves around nanomaterial synthesis. It pursues the optimised formulation of nanostructured CeO2, a semiconductor material that holds a broad set of intrinsic catalytic properties, describing the synthesis of the minimal stable size for colloidal monocrystalline particles of the material and its complete physicochemical characterization (size, composition, morphology, crystal structure, optical and colloidal properties). It is followed by the extension of the material’s functionality through different derivation strategies, such as doping with different trivalent lanthanide ions and coupling to plasmonic metal domains (Au and Ag) via different synthetic approaches to produce several types of hybrid architectures (core-shell, heterodimers, hollow structures, and other anisotropic shapes) of controlled size. The second part of this work involves the characterization of structure-activity relations of the CeO2-based nanomaterials synthesised in the first part. These are evaluated first through the catalytic performance of each nanomaterial. It has been carried out for two different processes. As a heterogeneous catalyst for methanol production and as ROS scavenger for biomedical applications, coupled with the correspondent assessment of the nanomaterials’ toxicity through in vitro assays. To complete the description of the structure-activity relations, the characterization of the singular electronic structure of CeO2, that confers its characteristic catalytical properties, has been also carried out. Employing core-level spectroscopic techniques, the differences between bulk and nanosized CeO2 have been evaluated through the Ce 3d and O 1s spectra in XPS and Ce L3 edge in XANES., [cat] L'objectiu principal d'aquesta tesi doctoral és fomentar ponts entre la ciència de materials i els seus diferents camps d'aplicació. Partint d'aquesta premissa, la finalitat concreta del treball és assolir uns millor coneixement de les propietats catalítiques del CeO2 nanoestructurat i les aplicacions que en poden emergir. Per abordar aquesta qüestió, des de l'àmbit de la química s'ha de proveir d’una tecnologia capdavantera de síntesi de nanomaterials, capaç de millorar les eficiències dels processos químics reduint el consum d'energia i la producció de residus per minimitzar-ne l'impacte ambiental. Alhora, la investigació actual en síntesi de nanomaterials es fonamenta en el disseny i formulació dels mateixos sota el control total de les seves propietats fisicoquímiques, morfològiques i col·loidals. En conjunt amb la descripció adequada de les relacions activitat-estructura dels materials formulats, l'objectiu actual de la síntesi de nanomaterials és el disseny orientat a la aplicació final mitjançant la programació de les propietats del producte. Dins d'aquest marc, aquesta tesi compta amb dues parts. La primera gira al voltant de la síntesi de nanomaterials. Es busca la formulació optimitzada de nanocristalls de CeO2, un material semiconductor que posseeix un ampli ventall de propietats catalítiques, a través de la descripció de la síntesi de partícules col·loidals monocristal·lines de menor mida possible dins de la seva estabilitat termodinàmica. Aquesta part es completa amb l'extensió de la funcionalitat del material mitjançant diferents estratègies d'hibridació d'aquest, com ara bé el dopatge amb cations trivalents lantànids o l'acoblament de dominis de metalls plasmònics (Au i Ag) seguint diferents estratègies de síntesi. La segona part d'aquest treball tracta la caracterització de les relacions estructura-activitat dels materials ja sintetitzats en la primera. Aquestes són avaluades, en primer lloc, a través de la activitat catalítica de cada nanomaterial per a un procés de catàlisi heterogènia (producció de metanol) i com a neutralitzador de radicals lliures per aplicacions biomèdiques. En segon lloc, l'origen de les propietats catalítiques del material es descriu a través de la caracterització de la singular estructura electrònica del CeO2 nanostructurat, emprant tècniques d'espectroscòpia com XPS i XANES.

Raman spectroscopy and magnetic properties of the natural single crystalline diamonds irradiated with high fluences of fast reactor neutrons have been investigated. Raman spectra transformations were studied in the range from moderate levels up to radiation damage leading to diamond graphitization. The selection of fast neutrons irradiated diamonds for magnetic measurements was carried out according to Raman scattering data on the basis of the intensity criterion and the spectral position of the “1640” band. It was found that in natural diamonds irradiated with neutrons with an extremely high subcritical fluence F = 5 × 1020 cm−2, the transition from a diamagnetic to a ferromagnetic state is observed at the Curie–Weiss temperature of ≈150 K. The energy of the exchange magnetic interaction of uncompensated spins is estimated to be ≈1.7 meV. The differential magnetic susceptibility estimated from the measurements of magnetic moment for temperature 2 K in the limit of B ≈ 0 is χdiff ≈ 1.8 × 10−3 SI units. The nature of magnetism in radiation-disordered single-crystal hydrogen- and metal-free natural diamond grains was discussed.

In this work a wide sample analysis, under similar conditions, has been carried out and a calibration strategy based on a careful selection of input variables combined with sensitivity analysis has enabled us to build accurate neural network models, with high correlation (R > 0.99), for the prediction of the aspect ratio of micro/nanofiber products. The model is based on cellulose content, applied energy, fiber length and diameter of the pre-treated pulps. The number of samples used to generate the neural network model was relatively low, consisting of just 15 samples coming from pine pulps that had undergone thermomechanical, kraft and bleached kraft treatments to produce a significant range of aspect ratio. However, the ANN model, involving 4 inputs and 4 hidden neurons and calibrated on the basis of pine dataset, was accurate and robust enough to predict the aspect ratio of micro/nanofiber materials obtained from other cellulose sources including very different softwood and hardwood species such as Spruce, Eucalyptus and Aspen (R = 0.84). The neural network model was able to capture the nonlinearities involved in the data providing insight about the profile of the aspect ratio achieved with further homogenization during the fibrillation process The authors wish to acknowledge the fnancial support of the Spanish Ministry of Science and Innovation to the project CON-FUTURO-ES (PID2020-113850RB-C21 and PID2020-113850RB-C22) and VALORCON-NC (PDC2021- 120964-C21 and PDC2021-120964-C22). Open Access funding provided thanks to the CRUE-CSIC agreement with Springer Nature.

Summary Preserving the Mary Rose oak hull for future generations is a major challenge due to the highly heterogeneous nature of waterlogged wooden artifacts, which contain polycrystalline, amorphous, and nanostructured materials that test traditional characterization methods. Effective conservation requires detailed knowledge of the distribution and chemical nature of these species to develop strategies for preventing multiple chemo-mechanical degradation pathways. Here, we apply synchrotron-based computed tomography total scattering methods to the Mary Rose keelson wood that provides valuable position-resolved structural information on multiple embedded species of different length and concentration scales. We identify 5 nm zinc sulfide nanoparticles in the wood, presumably deposits from bacteria operating on the sulfur energy cycle under the anaerobic conditions on the seabed. These are identified as precursors to acid attack on the wood upon removal to an aerobic environment. These insights inform not only next-generation conservation strategies, but also the efficacy and unforeseen issues of previous treatments.

Over the last few decades, there has been a lot of focus on the development of electrochromic energy storage system (EESS) integrated technology, and numerous developments have taken place for their reliable performance. It is an emerging and exciting field of research, which is making a significant contribution to the advancement of technology by embedding two different technologies in a single device for a wide range of applications. While overcoming barriers related to the development of EESS and the goal of reliable efficiency motivates new developments in the energy storage systems (ESS). Nowadays, a very important goal in research is to make current life more comfortable by creating more convenient, highly excellent, and portable devices by incorporating more functionality into energy-saving materials. To date, EESS with many functions such as being highly flexible, stretchable, self-healing, photo-responsive, and self-charging has been extensively explored. With all the additional functionalities they can be used in the progression of various devices, such as in wearable electronics, as a power source for other small electronic devices, in smart electrochromic window (ECW) construction and, in information display systems, etc. The development of multifunctional ESS is required due to new objectives and high energy demand in line with existing and future energy-related requirements and therefore, its research and development are always ongoing with excellent efforts. However, the active electrode material studied so far and the various assembly techniques used for it, need to be systematically reviewed so that it can be used for further study to develop more efficient EESS. This report will give a brief overview of the exploited literature along with their performance statistics on the literature published so far in this field.

Nano-structured Mo/Fe intermetallics were synthesized from precursors that contained 72/28% and 30/70% molar ratios of Mo/Fe, which were given as precursors A and B, respectively. These precursors were prepared from the co-precipitation of aqueous hot solutions of ammonium heptamolybdate tetrahydrate (AHM) and ferrous oxalate. The dry precipitates were thermally treated using TG-DSC to follow up their behavior during roasting, in an Ar atmosphere of up to 700 °C (10° K/min). The TG profile showed that 32.5% and 55.5% weight losses were measured from the thermal treatment of precursors A and B, respectively. The DSC heat flow profile showed the presence of endothermic peaks at 196.9 and 392.5–400 °C during the thermal decomposition of the AHM and ferrous oxalate, respectively. The exothermic peak that was detected at 427.5 °C was due to the production of nano-sized iron molybdate [Fe2(MoO4)3]. An XRD phase analysis indicated that iron molybdate was the only phase that was identified in precursor A, while iron molybdate and Fe2O3 were produced in precursor B. Compacts were made from the pressing of the nano-sized precursors, which were roasted at 500 °C for 3 h. The roasted compacts were isothermally reduced in H2 at 600–850 °C using microbalance, and the O2 weight loss that resulted from the reduction reactions was continuously recorded as a function of time. The influence of the reduction temperature and precursor composition on the reduction behavior of the precursors was studied and discussed. The partially and completely reduced compacts were examined with X-ray powder diffraction (XRD), a reflected light microscope (RLM), and a scanning electron microscope (SEM-EDS). Depending on the precursor composition, the reduction reactions of the [Fe2(MoO4)3] and Fe2O3 proceeded through the formation of intermediate lower oxides, prior to the production of the MO/Fe intermetallic alloys. Based on the intermediate phases that were identified and characterized at the early, intermediate, and final reduction degrees, chemical reaction equations were given to follow up the formation of the MoFe and MoFe3 intermetallic alloys. The mechanism of the reduction reactions was predicted from the apparent activation energy values (Ea) that were computed at the different reduction degrees. Moreover, mathematical formulations that were derived from the gas–solid reaction model were applied to confirm the reduction mechanisms, which were greatly dependent on the precursor composition and reduction temperature. However, it can be reported that nano-structured MoFe and MoFe3 intermetallic alloys can be successfully fabricated via a gas–solid reaction technique at lower temperatures.

Ammonium (NH4+) ions are a primary contaminant in the river and along the waterside near an agricultural area, therefore, necessitating sensitive detection of pollutants before irreversibly damaging environment. Herein, a new approach of metal-organic framework-derived tungsten ethoxide/polypyrrole-reduced graphene oxide (MOFs-W(OCH2CH3)6/Ppy-rGO) electrochemical sensors are introduced. Through a simple hydrothermal process, Ppy-rGO is linked to tungsten ethoxide as an organic linker. This creates the MOFs-W(OCH2CH3)6/Ppy-rGO nanocrystal through hydrogen bonding. The synergistic combination of tungsten ethoxide and Ppy-rGO provides three-fold advantages: stabilization of Ppy-rGO for extended usage, enabling detection of analytes at ambient temperature, and availability of multiple pathways for effective detection of analytes. This is demonstrated through excellent detection of NH4+ ions over a dynamic concentration range of 0.85 to 3.35 µM with a ppb level detection limit of 0.278 µM (9.74 ppb) and a quantitation limit of 0.843 µM (29.54 ppb). The increment in the concentration of NH4+ ions contributes to the increment in proton (H+) concentration. The increment in proton concentration in the solution will increase the bonding activity and thus increase the conductivity. The cyclic voltammetry curves of all concentrations of NH4+ analytes at the operating potential window between −1.5 and 1.5 V exhibit a quasi-rectangular shape, indicating consistent electronic and ionic transport. The distinctive resistance changes of the MOFs-W(OCH2CH3)6/Ppy-rGO to various NH4+ ion concentrations and ultrasensitive detection provide an extraordinary platform for its application in the agriculture industry.

Recently, nanotechnology and nanoparticles (NPs) such as AgNPs and AuNPs have become important in analytical chemistry due to their great potential to improve the performance of electrochemical sensors. In this work, Ag and Au nanoparticles have been synthesized using a green route in which a grape stalk waste extract is used as a reducing agent to obtain metallic nanoparticles. These NPs were used to customize the surface of commercial screen-printed electrodes (SPCNFEs). The spin-coating method was used to modify commercial SPCNFEs under a nitrogen atmosphere. The resulting electrodes were used in a determination study of Cd(II), Pb(II), and U(VI) with differential pulse anodic stripping voltammetry (DPASV). The customized green AgNPs and AuNPs electrodes presented higher sensitivity and electroanalytical performance than the non-modified SPCNFE. The results showed that the best analytical parameters were obtained with the green, silver nanoparticle SPCNFEs, with a LOD of 0.12 μg L−1 for Pb(II), which is a lower value compared to the most restrictive regulation guidelines. Additionally, the U(VI) ion was successfully determined using the developed G-AgNPs-SPCNFE in spiked tap water, showing comparable results with the ICP-MS technique.

Aiming to improve their photocatalytic performance, titanate nanowires (TNW) were modified by Fe and Co (co)-doping, FeTNW, CoTNW and CoFeTNW samples, using a hydrothermal methodology. XRD characterization agrees with the existence of Fe and Co in the lattice structure.and the existence of Co2+ together with the presence of Fe2+ and Fe3+ in the structure was confirmed by XPS. The optical characterization of the modified powders shows the impact of the d–d transitions of both metals in the absorption properties of TNW, mainly in the creation of additional 3d energetic levels within the prohibited zone. The effect of the doping metal(s) in the recombination rate of photo-generated charge carriers suggests a higher impact of Fe presence when compared to Co. The photocatalytic characterization of the prepared samples was evaluated via the removal of acetaminophen. Furthermore, a mixture containing both acetaminophen and caffeine, a well-known commercial combination, was also tested. CoFeTNW sample was the best photocatalyst for the degradation of acetaminophen in both situations. A mechanism for the photo-activation of the modified semiconductor is discussed and a model proposed. It was concluded that both Co and Fe are essential, within the TNW structure, for the successful removal of acetaminophen and caffeine.

Carbon-ceramic composites (C/Cer) have been prepared by chemical vapor deposition of coal tar pitch onto clay substrates and characterized by thermogravimetric analyses, powder X-ray diffraction, Raman spectroscopy, and scanning and transmission electron microscopies (SEM and TEM). The study of the dc electrical conductivity, together with the determination of the Hall voltage sign, proves that such C/Cer composites are n-type semiconductors. Our results demonstrate that: 1) the mechanism of electrical conduction of C/Cer semiconductors proceeds through the pathways expected for amorphous solids (ie. variable-range hopping and heat-activated pathways at low and high temperatures, respectively); and 2) their transport properties are strongly dependent on the clay components, as evidenced by microscopy experiments. The authors would like to thank the financial support from Ministerio de Ciencia e Innovación (grant No. PID2019-105542RB-I00/AEI/10.13039/501100011033 ), the European Union (FEDER Funds), and Generalitat Valenciana (grant No. PROMETEO CIPROM/2021/70 ).

Today, the increase in fuel consumption with the increasing number of vehicles has increased the efforts to make the engines more efficient. Diesel engines are subject to severe restrictions due to the emission problem. Although there is an emission problem, it is widely used especially in freight transportation. Many studies on diesel engines emission problems are made by academicians and manufacturers. In this sense, many studies have been carried out by adding nanomaterials to diesel fuel to reduce emissions in diesel engines. In this study, borax decahydrate as a fuel additive was studied in a diesel single-cylinder engine. Borax decahydrate was dissolved in 500 ml of methanol, 5 gr, 15 gr and 25 gr, and methanol was added to 10% diesel. To be 90% Diesel +10% Methanol (D90M10) 90% Diesel 10% Methanol + 1 gr Borax decahydrate (D90M10B1) 90% Diesel 10% Methanol + 3 gr Borax decahydrate (D90M10B2) 90% Diesel 10% Methanol + 5 gr Borax decahydrate (D90M10B3) four different fuel mixtures were tested. The experimental test measured in-cylinder pressure, heat release rate, fuel consumption, power, torque, exhaust gas temperature, smoke opacity, and exhaust emissions. Due to the rich oxygen content of borax decahydrate, it has been observed to reduce emissions, excluding NOx emissions. There was an increase in exhaust temperature, nitrogen oxides (NOx), and carbon dioxide (CO2) emissions and a serious decrease in HC, CO, brake-specific fuel consumption, and smoke opacity values. Studies should be expanded and enriched with different mixing ratios and usage patterns of boron-doped fuels in the future. © 2022 Elsevier Ltd

Diverse sources of energy are becoming increasingly significant in today's world. The most common source of energy today is fossil fuels, such as coal, oil, and gas. While this energy source has many advantages, it also comes with many problems. In order to meet this demand, environmentally friendly and sustainable alternatives to energy are urgently needed. Renewable energy such as hydro, wind, photovoltaics, biomass, and geothermal is an attractive and promising kind of energy. Solar energy is among the most efficient, cleanest, and cheapest sources of energy. In this thesis, two photo-processes are utilized to produce solar energy using nanostructured materials. One is photocatalysis, mainly photoelectrochemical (PEC) water splitting for hydrogen production and photodegradation of organic dyes, and another is a sunlight-powered photovoltaic cell. In this thesis, we aim to demonstrate optimized low-cost sustainable electrodes based on nanostructured materials for solar energy applications. For PEC water splitting two materials namely ZnO NRs and CuO NLs are fabricated by hydrothermal methods followed by deposition of different materials such as Ag2WO4 and AgBr. These materials show relatively high PEC water splitting efficiency using sunlight. Similarly, for the photodegradation of organic dyes Ta2O5 is used with the addition of Ag/AgCl nanoparticles (Ag/AgCl NPs), which results in an effective plasmonic photocatalyst for the removal of water-soluble Congo red (CR) dye compounds. For high-efficiency solar cells two methods are applied. Firstly, a FDTD simulation method was applied to study the plasmon enhancement of light absorption from p-i-n junction GaAs nanowires. Secondly a study of anisotropic deformation of colloidal particles exposed to heavy ions irradiation. Finally, a novel low-cost template-assisted method was used in order to improve the alignment of ZnO NRs grown on Si substrates. Idag finns det ett ökat behov av olika energikällor. Den energikälla som i stor utsträckning används är fossilt bränsle, som till exempel kol, olja och gas. Emellertid finns det många kriser som associeras med denna energikälla. Därför är det bråttom att utveckla alternativa energikällor som är ekologiska och uthålliga. Förnybara energikällor som väte, vind, sol, biomassa och geotermisk energi är attraktiva. I denna avhandling demonstrerar vi två fotoprocesser som använder solenergi och är baserade på nanostrukturmaterial. Den första metoden som vi använder är fotokatalys: fotoelektrokemisk (PEC) vattensplittring för väteproduktion. Den andra metoden är fotodegradering av organiska färgämnen genom att använda solstrålning som inkommande energi. Dessutom undersöker vi hur nanotrådar kan användas som aktiva solceller. Avsikten med avhandlingen är att demonstrera optimiserade, billiga och uthålliga elektroder baserade på nanostrukturer för solenergitillämpningar. För PEC baserad vattensplittring använder vi två material, ZnO och CuO, som tillverkas med hjälp av hydrotermisk metoder följt av att vi deponerar olika material som Ag2WO4, och AgBr. Dessa material visar relativt hög effektivitet för PEC baserade användande av synligt solljus. För fotodegradering av organiska färgämnen användes Ta2O3 följt av deponering av Ag/AgCl nanopartiklar, som resulterar i effektiv plasmonisk fotokatalys för borttagande av det vattenlösliga Congo röda färgämnet. För högeffektiva solceller tillämpas två metoder först, en FDTD-simuleringsmetod användes för att studera plasmonförstärkningen av ljusabsorption från’’p-i-n junction’’ GaAs nanotrådar. För det andra en studie av anisotrop deformation av kolloidala partiklar under kraftig jonbestrålning. Slutligen användes en ny, billig mallassisterad metod för att förbättra anpassningen av ZnO NRs odlade på Si substrat.

Chemical vapor deposition was applied to synthetize nanostructured deposits containing several sorts of nanoobjects (i.e., nanoballs, irregular particles, and nanowires). Analytical techniques, that is, high-resolution transmission electron microscopy, scanning electron microscopy, electron dispersive X-ray analysis, selected area electron diffraction, and X-ray photoelectron spectroscopy, showed that unlike nanoballs and particles composed of crystalline germanium, the layer was made of chromium germanide CrGex. The nanowires possessed a complex structure, namely a thin crystalline germanium core and amorphous CrGex coating. The composition of the nanowire coating was [Cr]/[Ge] = 1:(6–7). The resistance of the nanowire–deposit system was estimated to be 2.7 kΩ·cm using an unique vacuum contacting system.

Hazardous gases have been strongly associated with being a detriment to human life within the environment. The development of a reliable gas sensor with high response and selectivity is of great significance for detecting different hazardous gases. TiO2 nanomaterials are promising candidates with great potential and excellent performance in gas sensor applications, such as hydrogen, acetone, ammonia, and ethanol detection. This review begins with a detailed discussion of the different dimensional morphologies of TiO2, which affect the gas sensing performance of TiO2 sensors. The diverse morphologies of TiO2 can easily be tuned by regulating the manufacturing conditions. Meanwhile, they exhibit unique characteristics for detecting gases, including large specific surface area, superior electron transport rates, extraordinary permeability, and active reaction sites, which offer new opportunities to improve the gas sensing properties. In addition, a variety of efforts have been made to functional TiO2 nanomaterials to further enhance sensing properties, including TiO2-based composites and light-assisted gas sensors. The enhanced gas sensing mechanisms of multi-component composite nanomaterials based on TiO2 include loaded noble metals, doped elements, constructed heterojunctions, and compounded with other functional materials. Finally, several studies have been summarized to demonstrate the comparative sensing properties of TiO2-based gas sensors.

Colloidal self-assembly refers to a solution-processed assembly of nanometer-/micrometer-sized, well-dispersed particles into secondary structures, whose collective properties are controlled by not only nanoparticle property but also the superstructure symmetry, orientation, phase, and dimension. This combination of characteristics makes colloidal superstructures highly susceptible to remote stimuli or local environmental changes, representing a prominent platform for developing stimuli-responsive materials and smart devices. Chemists are achieving even more delicate control over their active responses to various practical stimuli, setting the stage ready for fully exploiting the potential of this unique set of materials. This review addresses the assembly of colloids into stimuli-responsive or smart nanostructured materials. We first delineate the colloidal self-assembly driven by forces of different length scales. A set of concepts and equations are outlined for controlling the colloidal crystal growth, appreciating the importance of particle connectivity in creating responsive superstructures. We then present working mechanisms and practical strategies for engineering smart colloidal assemblies. The concepts underpinning separation and connectivity control are systematically introduced, allowing active tuning and precise prediction of the colloidal crystal properties in response to external stimuli. Various exciting applications of these unique materials are summarized with a specific focus on the structure-property correlation in smart materials and functional devices. We conclude this review with a summary of existing challenges in colloidal self-assembly of smart materials and provide a perspective on their further advances to the next generation.

Fuel cell is a promising technique as a renewable source of energy. The beginning and development of fuel cells started since the early 1800s. Fuel cells can be classified according to the used electrolyte (acidic and alkaline fuel cells) or according to the operating temperature (low and high-temperature fuel cells). Each type has particular features needed for its applications. However, the fuel cells that used traditional Pt-based electrodes suffer from some disadvantages such as poor duration, methanol crossover, CO poisoning, shortage of resources and high costs. Subsequently, improving the fuel cell performance received an intensive interest. In the recent years, researchers are working continuously to enhance the performance of the fuel cells’ components such as utilization of nanostructured materials to modify the efficiency of the electrodes. This review article will give a short overview on the usage of nanostructured materials as catalysts to improve the kinetics of the reactions occurring in fuel cells; especially the oxygen reduction reactions (ORR) that take place at the cathode.

Introduction. Advanced technologies impress people’s imagination demonstrating the latest achievements (materials, methods, systems, technologies, devices etc.) that dramatically change the world. This, first of all, concerns nanotechnological inventions designed by scientists, engineers and specialists from different countries. Main part. The article provides an abstract overview of inventions of scientists, engineers and specialists from different countries: Russia, USA, China, Belarus, Italy. The results of the creative activity of scientists, engineers and specialists, including inventions in the field of nanotechnology and nanomaterials allow, when introduced to industry, achieving a significant effect in construction, housing and communal services, and related sectors of the economy. For example, the invention «Protective coating and method of its application» relates to the field of protecting metals from corrosion. To obtain a protective coating, a composition containing an industrial oil with a powder of a phosphorusmodified copper-carbon nanocomposite is applied to the surface of an unalloyed steel and subjected to thermochemical activation by heating for 20 minutes at a temperature of 100–200°C. During the formation of the coating, strong donor-acceptor bonds of iron atoms with phosphorus, which are in the composition of the copper-carbon nanocomposite, are formed. In the course of experiments, it was found that heating samples with a coating of oil with the addition of a phosphorus-modified copper-carbon nanocomposite to 100–200°C increases the chemical activity of the nanocomposite, as a result of which a protective coating forms on the surface, which reduces the corrosion rate depending on the concentration of the modified metal-carbon nanocomposite. by 70–95%. The following inventions in the field of nanotechnology are also of interest to specialists: a method for obtaining a nanostructured surface of a metal workpiece by laser treatment, a device for producing nanodispersed metal oxides, a method for producing a nanostructured composite material based on aluminum, a method for modifying the surfaces of plates of a brazed plate heat exchanger, etc. Conclusion. One of the most challenging tasks the economy of every country face is to increase industrial competitiveness through technological upgrade. From the side of the state and companies the principal object to control in this process are the people and enterprises dealing with introduction of inventions and new technologies.

El óxido de zinc (ZnO) es un material con un amplio repertorio de propiedades ópticas, piezoeléctricas, actividad antimicrobiana, semiconductividad y fotocatalíticas que lo hacen útil en un gran número de aplicaciones. Sin embargo, el aumento de la preocupación por el impacto medio – ambiental ha llevado a desarrollar procesos ecológicos para su producción. En los últimos años, la síntesis verde de materiales nanoestructurados ha ganado atención por ser un método no complejo, económico y respetuoso con el medio ambiente en contraste con los métodos físicos y de síntesis química. Se han desarrollado diferentes nanomateriales empleando sustratos biológicos de entre los cuales los más estudiados son los extractos vegetales que fungen como una fuente de agentes reductores y / o estabilizadores. Por lo tanto, la presente revisión incluye un resumen de las diferentes fuentes de extractos vegetales y metodologías aplicadas a la síntesis verde de nanopartículas y películas delgadas de óxido de zinc y los avances en cuanto a la eficiencia de la actividad fotocatalítica de los materiales sintetizados. En este trabajo también presentamos un mapeo bibliométrico sobre el crecimiento de estudios en la materia en un periodo de 10 años comprendido entre el año 2011 y el 2020.

Nanotechnology is a top priority research area in a plethora of technological and scientific fields due to its economic impact and versatile capability. Among various applications, water treatment is considered among the most prospective utilization of nanotechnology, where a large number of nanostructured materials can remediate water using several different mechanistic ways. For achieving this, nanomaterials can be combined and modified with active moieties to develop different nanocomposites with structural diversity and unique physicochemical attributes. In addition, they have also been designed and integrated into membranes for improving water treatment performance. In this review, we provide an up-to-date overview of various nanostructured materials as nanoadsorbents, such as carbon-based nanomaterials, nanocomposites, and nanomembranes for remediating pesticide-based pollutants from aqueous systems using CNTs. Notably, nanomaterials are capable of efficiently removing environmental pollutants given their substantial surface area, high absorptive ability, and excellent environmental selectivity and compatibility.

Nowadays, the emerging photoelectrochemical (PEC) bioanalysis has drawn intensive interest due to its numerous merits. As one of its core elements, functional nanostructured materials play a crucial role during the construction of PEC biosensors, which can not only be employed as transducers but also act as signal probes. Although both chemical composition and morphology control of nanostructured materials contribute to the excellent analytical performance of PEC bioassay, surveys addressing nanostructures with different dimensionality have rarely been reported. In this review, according to classification based on dimensionality, zero-dimensional, one-dimensional, two-dimensional, and three-dimensional nanostructures used in PEC bioanalysis are evaluated, with an emphasis on the effect of morphology on the detection performances. Furthermore, using the illustration of recent works, related novel PEC biosensing patterns with promising applications are also discussed. Finally, the current challenges and some future perspectives in this field are addressed based on our opinions.

International audience; The direct integration of performant permanent magnets (PMs) within miniaturized circuits remains both a scientific and a technological challenge. Magnetophoresis-driven capillary assembly of hard magnetic nanoparticles is a promising approach to fabricate 3D rare-earth-free PMs. However, this process implies the use of soft magnetic blocks to generate the magnetic field gradients required to localize the assembly directly onto silicon substrates. The impact of these soft elements onto the overall magnetic properties is evaluated using Co nanorods as hard material and 150 μm–thick Ni blocks. As expected, the presence of Ni softens the overall properties of the hybrid magnet obtained, but PM properties are preserved for reduced Ni volumes. Magnetic induction as high as 19 mT at a distance of 200 μm is generated by the hybrid Ni–Co–Ni structures, allowing for the electromagnetic actuation of a microelectromechanical resonant sensor

La versatilidad con la que se utiliza la nanotecnología facilita la posibilidad de encontrar diferentes soluciones a problemáticas en distintos campos multidisciplinarios, su uso promete curar una gran cantidad de enfermedades, incluso extender la esperanza de vida promedio, generar materiales más livianos y resistentes, soluciones con las cuales queremos contar para facilitar la vida humana. No obstante, no existen muchos estudios que indiquen a cabalidad los daños que estos nanomateriales puedan generar en la salud de las personas que los manipulan. Muchos de estos nanomateriales han generado cáncer de pulmón a los usuarios que los manipulan y aun no se sabe con certeza que otros tipos de riesgos para la salud podrían ocasionar estas nanopartículas ya que actualmente esta tecnología se encuentra en investigaciones. El desarrollo de esta nanotecnología está generando que más trabajadores se expongan a ese riesgo a medida que su demanda aumenta, es imprescindible formular medidas de prevención y mitigación que disminuya la vulnerabilidad de los usuarios por exposición laboral a nanomateriales. Este trabajo tiene como objetivo diseñar una guía para la valoración cualitativa del riesgo y la prevención de enfermedades laborales por nanomateriales en el contexto colombiano. La guía se formuló a través de una revisión de literatura científica nacional e internacional que posteriormente fue plasmada en una aplicación móvil la cual contiene las herramientas para valorar el riesgo por manipulación de nanopartículas y sus mecanismos de prevención y mitigación. Mediante la investigación se identificó la falta de estudios para la prevención del riesgo por estos tipos de materiales, ya que las referencias utilizadas en su mayoría usan la evaluación de riesgos de unos materiales análogos a los nanomateriales. The versatility with which nanotechnology is used facilitates the possibility of finding different solutions to problems in different multidisciplinary fields, its use promises to cure a large number of diseases, even extend the average life expectancy, generate lighter and more resistant materials, solutions that we want to count on to make human life easier. However, there are not many studies that fully indicate the damage that these nanomaterials can cause to the health of the people who handle them. Many of these nanomaterials have caused lung cancer in users who handle them and it is not yet known with certainty what other types of health risks these nanoparticles could cause, since this technology is currently under investigation. The development of this nanotechnology is causing more workers to be exposed to this risk as its demand increases, it is essential to formulate prevention and mitigation measures to reduce the vulnerability of users due to occupational exposure to nanomaterials. The objective of this work is to design a guide for qualitative risk assessment and prevention of occupational diseases caused by nanomaterials in the Colombian context. The guide was formulated through a review of national and international scientific literature that was subsequently translated into a mobile application containing the tools to assess the risk of handling nanoparticles and their prevention and mitigation mechanisms. The research identified the lack of studies for risk prevention for these types of materials, since the references used mostly use the risk assessment of materials analogous to nanomaterials. Tesis (Magíster en Seguridad y Salud en el Trabajo)-- Universidad Autónoma de Occidente, 2022 Maestría Magíster en Seguridad y Salud en el Trabajo

Väitekirja elektrooniline versioon ei sisalalda publikatsioone, Alumiiniumsulamid on kerged ning suurepäraste mehaaniliste omadustega, mille tõttu kasutatakse neid laialdaselt komponentide valmistamiseks lennu- ja autotööstuses. Paraku on parimad alumiiniumsulamid tundlikud korrosiooni suhtes, mida saab takistada erinevate kaitsekatete abil. Põhiliseks väljakutseks on seejuures kaitse tagamine täppisdetailidele, mille mõõtmed ei tohi palju muutuda ja mis võivad olla keeruka kolmemõõtmelise kujuga ning sisaldada ka keermetega auke. Selle probleemiga tegeleti antud uurimustöös, kus uuriti nanokatete rakendamist alumiiniumsulamite korrosioonikindluse tõstmiseks. Erinevate keraamiliste kaitsekatete valmistamiseks kasutati uurimustöös aatomkihtsadestuse meetodit, millega kaeti erineva eeltöötlusega alumiiniumdetailide. Süstemaatiliste uuringute vältel töötati välja uudne meetod et valmistada nanostruktuurseid kaitsekatteid, mis tagasid alumiiniumdetailidele suurepärase kaitse korrosiooni eest. Samuti testiti kaitsekatet energeetilise atomaarse hapnikuga, millega simuleeriti 1 aasta pikkust kokkupuudet kosmose tingimustega madalal orbiidil. Uudne nanostruktuurne kate on praeguseks kantud üle 50-le alumiiniumdetailile satelliidil WISA Woodsat, kus tema eesmärk on tagada funktsionaalsus kriitilistele liikuvatele detailidele. Samuti uuritakse peagi uudse katte käitumist kosmoses materjalide testimise mooduli abil, mis on integreeritud satelliidile ESTCube-2., Aluminum alloys are widely used for manufacturing components in aerospace and automobile industries. Aluminum alloys are favored in these applications as they have light weight and superior mechanical properties but are also easy to process. However, these alloys are vulnerable to corrosion, which can be mitigated by using various protective coatings. The primary challenge with aluminum alloys in practical applications is the protection of high precision substrates that may also have a sophisticated three-dimensional shape or contain threaded cavities. This problem was addressed in this study, where the use of nanometric protective coatings was investigated. For that purpose, atomic layer deposition technique was used to grow various ceramic materials onto the aluminum alloy substrates that had received different pre-treatments. During these systematic studies, a technique was developed for the preparation of a novel nanostructured coating which protected the aluminum alloy against corrosion in salt spray tests. The novel coating also suffered only negligible damage from energetic atomic oxygen, which was used to simulate 1 year of exposure to space in low Earth orbit. Finally, the novel nanostructured coating was successfully applied on over 50 aluminum parts of satellite WISA Woodsat and will also be tested soon in space on the materials testing module on ESTCube-2., https://www.ester.ee/record=b5526412

Large variations in the polarization resistance of La0.6Sr0.4Co0.2Fe0.8O3-δ (LSCF) cathodes are reported in the literature, which are usually related to different preparation methods, sintering temperatures, and resulting microstructures. However, the influence of the electrolyte on the electrochemical activity and the rate-limiting steps of LSCF remains unclear. In this work, LSCF nanostructured electrodes with identical microstructure are prepared by spray-pyrolysis deposition onto different electrolytes: Zr0.84Y0.16O1.92 (YSZ), Ce0.9Gd0.1O1.95 (CGO), La0.9Sr0.1Ga0.8Mg0.2O2.85 (LSGM), and Bi1.5Y0.5O3-δ (BYO). The ionic conductivity of the electrolyte has a great influence on the electrochemical performance of LSCF due to the improved oxide ion transport at the electrode/electrolyte interface, as well as the extended ionic conduction paths for the electrochemical reactions on the electrode surface. In this way, the polarization resistance of LSCF decreases as the ionic conductivity of the electrolyte increases in the following order: YSZ > LSGM > CGO > BYO, with values ranging from 0.21 Ω cm2 for YSZ to 0.058 Ω cm2 for BYO at 700 °C. In addition, we demonstrate by distribution of relaxation times and equivalent circuit models that the same rate-limiting steps for the ORR occur regardless of the electrolyte. Furthermore, the influence of the current collector material on the electrochemical performance of LSCF electrodes is also analyzed.

14 páginas.- 5 figuras.- 4 tablas.- 71 referencias.- Supplementary Materials: The following supporting information can be downloaded at: https://www.mdpi.com/article/10.3390/molecules27217418/s1 .- his article belongs to the Special Issue Organic Nanomaterials: Synthesis and Applications, Biochar is a nanoengineered sorbent proposed to control the contamination derived from the presence of residual concentrations of sulfonamides in soil. In this work, we evaluated the sorption of sulfanilamide (SFA) in commercial biochar (BC) produced at 500 °C from oak hardwood (Quercus ilex) and its analog activated with 2% (w/w) Fe (BC-Fe). Subsequently, the effect on dissipation and transport of SFA in untreated soil and soil treated with BC and BC-Fe was also assessed. Laboratory batch studies revealed that BC-Fe increased the sorption of SFA as compared to the pristine BC with Kd of 278 and 98 L/kg, respectively. The dissipation of SFA in either untreated soil or soil treated with BC or BC-Fe was similar, displaying half-lives ranging between 4 and 6.4 days. Conversely, the concurrent determination of sorption during the incubation experiment showed that lower amounts of SFA in solution at the beginning of the experiments were bioavailable in BC-Fe-treated soil when compared to the rest of the treatments shortly after application. Leaching column studies confirmed the amendment’s capability to bind the SFA compound. Therefore, the decrease in bioavailability and movement of SFA in treated soils suggest that biochar soil application can reduce SFA soil and water contamination. According to our results, BC surface modification after Fe activation may be more appropriate for water decontamination than for soil since there were no significant differences between the two types of biochar when added to the soil. Therefore, these outcomes should be considered to optimize the SFA mitigation potential of biochar., This research was funded by the Spanish Ministry of Science and Innovation (MCIN/AEI/10.13039/501100011033) through grants PID2019-109456RB-I00 and by Junta de Andalucía, through grant P20-00746, with EU (FEDER) funds. The USDA is an equal-opportunity employer. Any mention of trade names or commercial products in this report is solely for the purpose of providing specific information and does not imply recommendation or endorsement by the U.S. Department of Agriculture. Institutional Review Board Statement

The removal of dyes from textile effluents utilizing advanced wastewater treatment methods with high efficiency and low cost has received substantial attention due to the rise in pollutants in water. The purpose of this work is to give a comprehensive analysis of the different treatments for removing chemical dyes from textile effluents. The capability and potential of conventional treatments for the degradation of dyeing compounds in aqueous media, as well as the influence of multiple parameters, such as the pH solution, initial dye concentration, and adsorbent dose, are presented in this study. This study is an overview of the scientific research literature on this topic, including nanoreductive and nanophotocatalyst processes, as well as nanoadsorbents and nanomembranes. For the purpose of treating sewage, the special properties of nanoparticles are currently being carefully researched. The ability of nanomaterials to remove organic matter, fungus, and viruses from wastewater is another benefit. Nanomaterials are employed in advanced oxidation techniques to clean wastewater. Additionally, because of their small dimensions, nanoparticles have a wide effective area of contact. Due to this, nanoparticles' adsorption and reactivity are powerful. The improvement of nanomaterial technology will be beneficial for the treatment of wastewater. This report also offers a thorough review of the distinctive properties of nanomaterials used in wastewater treatment, as well as their appropriate application and future possibilities. Since only a few types of nanomaterials have been produced, it is also important to focus on their technological feasibility in addition to their economic feasibility. According to this study, nanoparticles (NPs) have a significant adsorption area, efficient chemical reactions, and electrical conductivity that help treat wastewater effectively. This research was funded by the University of Girona, project UNIGE-01 and Spanish MCIN, project PID2020-112975GB-I00.

Food packaging manufacturers often resort to lamination, typically with materials which are neither non-biodegradable nor biobased polymers, to confer barrier properties to paper and cardboard. The present work considers a greener solution: enhancing paper’s resistance to moisture, grease, and air by aqueous coating suspensions. For hydrophobization, a combined approach between nanocellulose and common esterifying agents was considered, but the water vapor transmission rate (WVTR) remained excessively high for the goal of wrapping moisture-sensitive products (>600 g m−2 d−1). Nonetheless, oil-repellant surfaces were effectively obtained with nanocellulose, illite, sodium alginate, and/or poly(vinyl alcohol) (PVA), reaching Kit ratings up to 11. Regarding air resistance, mineral-rich coatings attained values above 1000 Gurley s. In light of these results, nanocellulose, minerals, PVA, pullulan, alginate, and a non-ionic surfactant were combined for multi-purpose coating formulations. It is hypothesized that these materials decrease porosity while complementing each other’s flaws, e.g., PVA succeeds at decreasing porosity but has low dimensional stability. As an example, a suspension mostly constituted by nanocellulose, sizing agents, minerals and PVA yielded a WVTR of roughly 100 g m−2 d−1, a Kit rating of 12, and an air resistance above 300 s/100 mL. This indicates that multi-purpose coatings can be satisfactorily incorporated into paper structures for food packaging applications, although not as the food contact layer The authors wish to acknowledge the financial support of the Spanish Ministry of Science and Innovation to the projects CON‐FUTURO‐ES (PID2020‐113850RB‐C22) and NextPack (PID2021‐124766OA‐I00)

The nanostructuration of solid matrices with lipid nanoparticles containing membrane proteins is a promising tool for the development of high-throughput screening devices. Here, sol-gel silica-derived nanocomposites loaded with liposome-reconstituted KcsA, a prokaryotic potassium channel, have been synthesized. The conformational and functional stability of these lipid nanoparticles before and after sol-gel immobilization have been characterized by using dynamic light scattering, and steady-state and time-resolved fluorescence spectroscopy methods. The lipid-reconstituted KcsA channel entrapped in the sol-gel matrix retained the conformational and stability changes induced by the presence of blocking or permeant cations in the buffer (associated with the conformation of the selectivity filter) or by a drop in the pH (associated with the opening of the activation gate of the protein). Hence, these results indicate that this novel device has the potential to be used as a screening platform to test new modulating drugs of potassium channels.

Colloidal nanomaterials of metals, metal oxides, and metal chalcogenides have attracted great attention in the past decade owing to their potential applications in optoelectronics, catalysis, and energy conversion. Introduction of various synthetic routes has resulted in diverse colloidal nanostructured materials with well-controlled size, shape, and composition, enabling the systematic study of their intriguing physicochemical, optoelectronic, and chemical properties. Furthermore, developments in the instrumentation have offered valuable insights into the nucleation and growth mechanism of these nanomaterials, which are crucial in designing prospective materials with desired properties. In this perspective, recent advances in the colloidal synthesis and mechanism studies of nanomaterials of metal chalcogenides, metals, and metal oxides are discussed. In addition, challenges in the characterization and future direction of the colloidal nanomaterials are provided.

Hypothesis Self-similarity is a scale-invariant irregularity that can assist in designing a robust superhydrophobic material. A combinatorial design strategy involving self-similarity and dual-length scale can be employed to create a new library of a doubly re-entrant, disordered, and porous network of superhydrophobic materials. Asymmetric wettability can be engineered in nonwoven materials by rendering them with superhydrophobic characteristics on one side. Experiments A facile, scalable, and inexpensive spray-coating technique was used to decorate the weakly hydrophobic stearate-treated titanate nanowires (TiONWs) over the self-similar nonwoven material. Laser scanning confocal microscopy was employed to image the impalement dynamics in three dimensions. With the aid of X-ray microcomputed tomography analysis, the three-dimensional (3D) nonwoven structural parameters were obtained and analyzed. The underwater superhydrophobic behavior of the prepared samples was investigated. Findings A classic 'lotus effect' has been successfully endowed in self-similar nonwoven-titanate nanostructured materials (SS-Ti-NMs) from a nonwoven material that housed the air pockets in bulk and water repellent TiONWs on the surface. The finer fiber-based SS-Ti-NMs exhibited lower roll-off angles and a thinner layer of water on its surface. An asymmetric wettability and the unusual display of underwater superhydrophobic behavior of SS-Ti-NMs have been uncovered.

The technology of hydrothermal carbonization (HTC) is a thermal chemical conversion process of organic waste into products in a reactor at low and medium temperatures and pressures, with catalysts, using residual raw materials of diversified origin, such as domestic, industrial, or agricultural. The products from the process have several energies (renewable sources) and environmental applications, such as carbon sink, soil conditioners and nanostructured materials. Implications inherent to the process, such as the type of residual biomass, the carbon phases produced (products), and adaptation of the small-scale system, have been researched in the activities. Experiences show that a laboratory-scale system transforms wet biomass from industrial waste, such as septic tank sludge, into products with application potential. The septic tank effluent originating from the great region of Goiânia was treated through hydrothermal carbonization, generating products in nanometer scale to which value could be added (potential result), in case of application at an industrial scale. A tecnologia de carbonização hidrotermal (HTC) trata de processo de conversão termoquímica de substâncias residuárias orgânicas em produtos em reator em baixas e médias temperaturas e pressões, com catalisadores, utilizando matérias-primas residuais de origem diversificada, tais como doméstica, indústria ou agrícola. Os produtos do processo apresentam diversas aplicações energéticas (fontes renováveis) e ambientais, tais como sumidouro de carbono, condicionadores de solo e materiais nanoestruturados. Implicações inerentes ao processo, tais como o tipo de biomassa residuária, as fases de carbono produzidas (produtos) e adaptação do sistema de pequena escala, têm sido pesquisadas nas atividades. Experiências mostram que sistema em escala laboratorial transforma biomassa úmida de resíduos industriais, como lodo de fossas sépticas, em produtos com potencial de aplicação. O efluente de fossa séptica originário da grande região de Goiânia foi tratado através da carbonização hidrotermal, gerando produtos na escala nanométrica, aos quais poderiam ser agregados valor (resultado potencial), em caso de aplicação na escala industrial.

Seed priming is a cost-effective, practical, environmental, and farmer-friendly method to improve seed germination that can potentially increase the growth and yield of plants. The priming process enhances various physiological and biochemical mechanisms of defense and empowers the seeds or seedlings to overcome different environmental stresses. However, under critical circumstances, plants are hindered from absorbing specific chemical priming reagents owing to their larger size, molecular structure, or lack of carriers. Therefore, nanoscale materials having exceptional physiochemical properties and a large surface/volume ratio are expected to be better absorbed by the seeds/seedlings as priming agents in comparison to bulk chemicals and can trigger enhanced molecular interactions at the cellular level. Further, the flexibility in altering the surface chemical properties of the nanomaterials can facilitate better interaction with the seeds/seedlings while inhibiting the wastage of priming agents. In this review, we have systematically discussed the potentiality of various nanostructured materials as priming agents in alleviating the adverse effects of various abiotic stresses, viz., drought, salinity, high temperature, cold temperature, and heavy metals, by studying the growth parameters and physiological and biochemical response of various crop plants subjected to these stress conditions. Also, we have highlighted the molecular mechanism and activation of genes involved in enabling abiotic stress tolerance in plants after being primed with nanostructured materials.

Contagious diseases are the principal cause of mortality, particularly respiratory viruses, a real menace for public health and economic development worldwide. Therefore, timely diagnosis and treatments are the only life-saving strategy to overcome any epidemic and particularly the ongoing prevailing pandemic COVID-19 caused by SARS-CoV-2. A rapid identification, point of care, portable, highly sensitive, stable, and inexpensive device is needed which is exceptionally satisfied by sensor technology. Consequently, the researchers have directed their attention to employing sensors targeting multiple analyses of pathogenic detections across the world. Nanostructured materials (nanoparticles, nanowires, nanobundles, etc.), owing to their unique characteristics such as large surface-to-volume ratio and nanoscale interactions, are widely employed to fabricate facile sensors to meet all the immediate emerging challenges and threats. This review is anticipated to foster researchers in developing advanced nanomaterials-based sensors for the increasing number of COVID-19 cases across the globe. The mechanism of respiratory viral detection by nanomaterials-based sensors has been reported. Moreover, the advantages, disadvantages, and their comparison with conventional sensors are summarized. Furthermore, we have highlighted the challenges and future potential of these sensors for achieving efficient and rapid detection.

S porastom potrebe za djelotvornim i oporabljivim rješenjima za uspješno vođenje različitih kemijskih reakcija znanstveno-istraživački radovi usmjereni su ka pronalasku djelotvornih i ekološki prihvatljivih katalizatora, nosača djelatnih tvari, adsorbensa za vlagu i stakleničke plinove. U ovome je radu opisana sinteza i karakterizacija jednog takvog potencijalnog katalizatora: cerijeva(IV) oksida dopiranog cirkonijem. Uzorci su pripremljeni metodom nanolijevanja pomoću krutog predloška na mezoporoznoj siliki, čija je sinteza također sastavni dio ovoga rada. Nanostrukturirani materijali, naročito porozni keramički materijali, pokazuju se kao izvrsni adsorbensi, katalizatori te nosači djelatnih tvari u farmaceuticima zbog svoje iznimno velike specifične površine, što utječe na visok broj aktivnih mjesta na površini tih materijala. Pripravljeni su uzorci okarakterizirani raznim karakterizacijskim tehnikama te su u ovome radu izneseni rezultati ispitivanja i prokomentirana svojstva mezoporoznih nanostrukturiranih keramičkih materijala. Following the rising need for efficient and recyclable solutions for the successful management of a variety of chemical reactions scientific efforts are directed towards finding efficient and ecologically acceptable catalysts, carriers of active substances, humidity and greenhouse gas adsorbents. The synthesis and characterization of one such potential catalyst is described in this paper: zirconium doped cerium(IV) oxide. The samples have been prepared using the method of nanocasting with formerly synthesised mesoporous silica serving as a hard template. Nanostructured materials, especially porous ceramics, have shown themselves to be excellent adsorbents, catalysts and active substance carriers in pharmaceutics because of their significantly large specific surface area, which results in a vast number of active points on the surface of these materials. Synthesised samples have been characterized by various characterization techniques and the results of them, as well as the properties of mesoporous nanostructured ceramics are described in this paper.

Thermophotovoltaic conversion using heat to generate electricity in photovoltaic cells based on the detraction of thermal radiation suffers from many engineering challenges. The focus of this paper is to study the nanostructure of AlGaAsSb for thermophotovoltaic energy conversion using lattice-matched heterostructures of GaSb-based materials in order to overcome the current challenges. The XAFS spectroscopy technique was used to analyze electronic structures and optical properties of GaSb, (Al, In) GaSbAs. The XAFS spectroscopy analysis showed a powerful decay at peak intensity that reveals to be related to a loss in Sb amount and light As atoms replaced in Sb atoms by 25%. Moreover, it was found that Al/In doped samples have highly symmetric data features (same atomic species substitution). The narrow direct bandgap energy, Eg of Al0.125Ga0.875Sb0.75As0.25 material raised (0.4–0.6 eV) compared to conventional photovoltaic cell bandgap energy (which is generally less than 0.4 eV) with weak absorption coefficients. The thermoelectric properties of AlGaAsSb computed via Botlztrap code showed that the electrons made up the majority of the charge carriers in AlGaAsSb. This nanostructure material exhibited a higher and acceptable figure of merit and demonstrated a promising thermoelectric material for solar thermophotovoltaic applications.

Rhabdomyosarcoma (RMS) is one of the most common soft tissue sarcomas and is extremely aggressive and highly malignant. The majority of cases occur in children, and most commonly appear in the arms or legs. Currently, RMS is treated with aggressive chemotherapy, as well as surgery and/or radiation in many cases. The aggressive treatments often cause long term aftereffects, and can even cause permanent life-altering disabilities. Alternative treatment modalities are urgently needed. The aim of this work is to build a dual-functional therapy/near-infrared (NIR) imaging nanoparticle, which could perform gene therapy with specific RMS gene knock-down regulated by pH-activated-release, and monitor the effects on tumour size with delivered near-infrared (NIR) dye. The nanoparticle will be surface functionalized with novel aptamers for improved targeting. The design can therefore be separated into four parts from outside to inside: aptamerbased targeting system, a pH-responsive charge reversible coating layer, nanoparticle-based NIR non-invasive imaging, and nanoparticle transfected siRNA for alveolar RMS (aRMS) specific gene knockdown. Aptamers were chosen as the targeting ligand for the nanosystem since compared to antibodies, they are much smaller, have higher affinity and specificity, and lower immunogenicity. Furthermore, they are easier and cheaper to manufacture. The binding target for aptamer generation was Neural EGF-Like 1 (NELL1) chosen based on validation results which suggested overexpression on the surface of the target aRMS cells. Oligos were isolated, and their binding affinity was quantified using Surface Plasmon Resonance (SPR). The selected NELL1 aptamer could locate and firmly bind to the NELL1 on the surface of aRMS cells, which could therefore potentially minimize off-target effects. The aptamer was attached to a synthesized pH-activated charge reversible PMPC-PDPA@PEG- 2 b-PAMA/DMMA copolymer layer. The PEG-b-PAMA/DMMA within the copolymer was able to efficiently convert the charge from negative (under physiological pH) to positive (under acidic pH), and the PMPC-PDPA could revert from a hydrophilic to a hydrophobic state after being activated by the acidic environment of tumours and subcellular organelles (endosomes & lysosomes). The enhanced tissue accumulation and cellular uptake could be achieved with increased adsorption onto negatively charged cellular membranes. For NIR imaging, IR820 NIR dye was loaded into the mesoporous silica nanoparticles core to enable non-invasive monitoring of the uptake and accumulation of the nanosystem during treatment. Compared with free IR820 dye which could only rely on passive diffusion, the IR820- loaded MSNPs were found to have significant improvements from the perspectives of cellular uptake, accumulation amount and penetration depth within both 2D and 3D cell models. Two siRNA targeting options were selected and validated for aRMS gene therapy: (i) Human αB-crystallin (CRYAB) & Heat Shock Protein Family B (Small) Member 2 (HSPB2) double knockout, and (ii) Keratin 17 (KRT17) knockdown. Through linking the validated siRNAs onto the MSNPs surface with the disulfide bound which could only be cleavaged by the high concentration of GSH within RMS cells, it has been found to have a high degree of RNase I degradation prevention, and a significant enhanced transfection efficiency. The total GSH levels within RD and RH30 cells were found to be 5.08 and 9.28 times higher than that of control fibroblast cells. Compared with the commercially available DharmaFect transfection reagent, the nanoparticles transfected siRNA has shown a similar or better level of gene knockdown; with a significant suppression of aRMS cells proliferation and mobility. Overall, the constructed nanosystem could provide another route for tackling aRMS in a more effective way, with fewer side-effects.

Growing transition metal oxides in the form of an ultrathin film can create new stoichiometries and structures that do not exist naturally, which may open new perspectives on the studies of oxide properties. This thesis focuses on the structural characterization of Nb, Ti, and V oxide thin films on the Au(111) substrates using scanning tunneling microscopy (STM). The work starts with ring patterns created by M-Au substitutions (M = Nb, Ti, V, Mn). According to the rings’ radii and centers, we can conduct a three-dimensional (3D) mapping of the substitutional sites. The ring's morphology is related to the curvature anisotropy of the Au isoenergy surface in k-space. Nb oxide has been studied most intensively in this project. Four structures of oxide monolayers have been identified which are (i) NbOx cluster, (ii) NbOy triangle, (iii) pinwheel, and (iv) the (2 × 2) Nb2O3 honeycomb (HC) structure. The pinwheel and honeycomb structures can form free films on the surface or embedded monolayers on the second layer. Nb-induced rings act as a precursor structure for an embedded monolayer. Fourfold coordinated Nb atoms in Nb2O3 HC appear much brighter in STM images. The actual oxidation state of a fourfold coordinated Nb atom is between +4 and +5 due to the electron transfer to Au. According to the contrast difference and coordination number, mapping the Nb oxidation states with atomic resolution at room temperature can be realized. Besides, fourfold coordinated Nb atoms are involved in point defects, edges, and domain boundaries. Discussions on HC edges and defects are organized in two chapters. Comparative analysis between Nb2O3 and Ti2O3 constitutes pivotal sections. Triangles and pinwheels are common structures in 2D materials. Nb and Ti oxides can form independently-standing triangles, and Nb/Ti/V oxides can generate both free and embedded pinwheel monolayers. A triangle building block model is proposed to elucidate the pinwheel comprising various sizes of triangle elements. Besides, Nb/Ti oxide triangles/pinwheels can be incorporated into HC monolayers by forming unique boundaries.

Chiral metasurfaces can transmit one circularly polarized light, while almost completely refuse the opposite handedness. In this project, a comparison of the optical properties of metallic vs high dielectric 2D chiral metasurfaces is made. Firstly, we discuss the general method to fabricate a chiral metasurface using the scalable technique of nanoimprinting soft lithography. Subsequently, numerical finite-difference time-domain (FDTD) simulations have been performed and compared with the experimentally measured chiroptical response of the nanoimprinted samples. These calculations show that each kind of metasurface presents a particular circular dichroism (CD), as plasmonic metasurfaces present better CD in transmittance due to their higher absorption, whereas the high dielectric materials can potentially generate chiral photoluminescence.