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Countries that do not have oil and natural gas but are forced to reduce pollution due to combustion have stimulated and developed new technologies for absorption, storage, and energy creation based on nanotechnology. These new technologies are up-and-coming because they will solve the problem without additional environmental burden. The first technology is based on phase change materials (PCMs) that store the thermal energy produced by the sun and release it when requested. In the context of this article, there is a discussion about some devices that arise from this technology. The second technology is based on light nano-traps that convert solar energy into heat, which is then stored by heating water or other methods. The third practice is to absorb solar energy from nanoparticles, producing electricity. These technologies' principles will be discussed and analyzed to understand their perspectives. [ABSTRACT FROM AUTHOR]

The self-healing of cementitious materials can be achieved by precipitation of calcium carbonate through the enzymatic hydrolysis of urea. When a crack appears in cement, the damage can be repaired by allowing bacteria to encounter the water seeping through the crack. This forms a calcium carbonate, which heals the cracks. This occurs because microorganisms begin metabolizing and precipitating the mineral, healing the damage caused by the crack. Then, bacteria are incorporated into various containers, which release microorganisms by crushing, leading to the precipitation of calcium carbonate. In addition, this paper references the superabsorbent polymers (SAP) used for self-healing and hybrid organic-inorganic core–shell SAPs, a recently developed, state-of-the-art self-healing technology for cementitious materials. [ABSTRACT FROM AUTHOR]

Recently, a subcategory of nanotechnology—nano-, and microcontainers—has developed rapidly, with unexpected results. By nano- and microcontainers, we mean hollow spherical structures whose shells can be organic or inorganic. These containers can be filled with substances released when given an excitation, and fulfill their missions of corrosion healing, cancer therapy, cement healing, antifouling, etc. This review summarizes the scattered innovative technology that has beneficial effects on improving people's lives. [ABSTRACT FROM AUTHOR]

Improved corrosion barrier coatings (CBCs) to protect metals will allow future metal structures to operate for extended periods, ensuring improved safety by reducing environmental pollution and maintenance costs. Many production methods and design of corrosion barrier coatings (CBCs) have been developed. This review focuses only on CBCs made with chemistry techniques. These CBCs can be passive and active with remarkable performance. Today, most of the work focuses on the discovery and application of "smart nanomaterials," which, if incorporated into "passive CBCs," will turn them into "active CBCs," giving them the phenomenon of "self-healing" that extends their service life. Today, many efforts are focused on developing sensors to diagnose corrosion at an early stage and CBCs that self-diagnose the environment and respond on demand. In addition, recent technological developments are reviewed, and a comprehensive strategy is proposed for the faster development of new CBC materials. [ABSTRACT FROM AUTHOR]

This paper reports developing an innovative method of anticorrosion protection based on organically modified silica (ORMOSIL) enriched with CeO2 ceramic nanocontainers loaded with 5-amino-1, 3, 4-thiadiazole-2-thiol (5-ATDT) on hot-dip galvanized zinc (HDG) steel used to strengthen cement in concrete. The chemistry of ORMOSIL coatings and the production of CeO2 ceramic nanocontainers are described in detail for reproduction by other researchers. The anticorrosion properties of these novel coatings were investigated through frequency response analysis (FRA). As a result, the coatings HDG-ORMOSIL + CeO2 (5-ATDT) were better than the samples of HDG steel, HDG-ORMOSIL, and HDG-ORMOSIL + CeO2 (EMPTY) by a factor of 1033.60, 109.21, and 7.76 in terms of anticorrosion protection, respectively. [ABSTRACT FROM AUTHOR]

We developed CuO and CeMo microcontainers, which were filled with Bromosphaerol (CuO (BR)), Sea‐Nine 211 (CuO (SN)) and 8‐Hydroxyquinoline (CeMo (8‐HQ)). We created coatings on metals using the basic resins we took from the WILKENS and Re‐Turn companies without additives of the companies. The coatings were studied in the laboratory after exposure to marine environment in Mikrolimano harbor in a distance of 12 km southwest from the city of Piraeus in the east coast of the Saronic Gulf (WILKENS) and Singapore harbor (Re‐Turn). Laboratory measurements showed that CeMo (8‐HQ) coatings exhibit better anticorrosion stability of paints in sea water than commercial paints. With regard to the incorporation of CuO (BR) into commercial paints, the results showed a drastic improvement in antifouling behavior from that resulting from commercial paints. The contact angle with water is improved by Θ = 70° to Θ = 115° possible through morphology of the surface due to the effect of the incorporation of microcontainers ensuring a better cruising behavior of the ship. This entails a dramatic rise in cruising speed, reducing fuel consumption and reducing air pollution. The technology was tested by the partial painting of two ships with our technology, one ship which traveled for a year in the Adriatic Sea (Sea Anemos) and the other traveled over a year in the Nord Sea (Berge Arzew). [ABSTRACT FROM AUTHOR]

CuCoMnOx spinels were fabricated onto aluminum substrates via sol‐gel processing. The aluminum substrates were anodized to produce rough substrate surface, so to achieve diffuse reflection of incoming light. First, hollow copper nanospheres CuO particles have been produced with a size of 715 ± 15 nm. The copper oxide nanospheres were coated with SiO2 yielding to a total diameter of 980 ± 30 nm comparable to the wavelength of FIR light. The resulting materials were characterized structurally and morphologically. The coatings were assessed with respect to absorptance αsol and emittance εT behavior, determining the α/ε ratio. In case of CuO@SiO2 microspheres incorporation into CuCoMnOx spinel coatings, the α/ε ratio reached the value α/ε of 30. The light trapping/scattering effect of CuO@SiO2 microspheres incorporation was demonstrated by the variation of the concentration up to 1 wt% and determination of α/ε ratio. Based on these measurements, the α/ε ratio increases linearly with increasing CuO@SiO2 microspheres concentration. [ABSTRACT FROM AUTHOR]

(100-x) mol % B2O3 x mol % Me2O (Me=Li,Na,K) glasses, exposed to γ-60Co irradiation to produce paramagnetic states, were characterized by W-band (95 GHz) pulse electron-nuclear double resonance (ENDOR) spectroscopy in order to characterize local structures occurring in the range of compositions between x=16 and x=25 at which the “boron oxide” anomaly occurs. The high resolution of nuclear frequencies allowed resolving the 7Li and 11B ENDOR lines. In the samples with x=16 and x=20 glasses, 11B hyperfine couplings of 16, 24, and 36 MHz were observed and attributed to the tetraborate, triborate, and boron oxygen hole center (BOHC) structures, respectively. The x=25 samples showed hyperfine couplings of 15 MHz for the tetraborate and 36 MHz for BOHC. Density functional theory (DFT) calculations predicted for these structures negative hyperfine couplings, which were confirmed by W-band ENDOR. This suggests that a spin polarization mechanism accounts for the negative hyperfine structure splitting. [ABSTRACT FROM AUTHOR]

Evaluates the electron spin echo envelope modulation (ESEEM) spectroscopy of silicate mineral and alkali metal glasses. Evaluation of ESEEM spectra revealing weak magnetic coupling between nonbridging oxygen (NBO) and the neighboring alkali metal; Covalent character between NBO and alkali metal.

5′,8-Cyclo-2′-deoxyadenosine (cdA) and 5′,8-cyclo-2′-deoxyguanosine (cdG) in their two diastereomeric forms, 5′Sand 5′R, are tandem lesions produced by the attack of hydroxyl radicals to the purine moieties of DNA. Their formation has been found to challenge the cells’ repair machinery, initiating the nucleotide excision repair (NER) for restoring the genome integrity. The involvement of oxidatively induced DNA damage in carcinogenesis and the reduced capacity of some cancer cell lines to repair oxidised DNA base lesions, intrigued us to investigate the implication of these lesions in breast cancer, the most frequently occurring cancer in women. Using liquid chromatography tandem mass spectrometry (LC-MS/MS), we measured the levels of diastereomeric cdA’s and cdG’s in estrogen receptor-alpha positive (ER-α) MCF-7 and triple negative MDA-MB-231 breast cancer cell lines before and after exposure to two different conditions: ionising radiations and hydrogen peroxide, followed by an interval period to allow DNA repair. An increase at the measured levels of all four lesions, i.e. 5′S-cdA, 5′R-cdA, 5′S-cdG and 5′R-cdG, was observed either afterγ-irradiation (5 Gy dose) or hydrogen peroxide treatment (300 μM) compared to the untreated cells (control), independently from the length of the interval period for repair. For comparison reasons, we also measured the levels of 8-oxo-2′-deoxyadenosine (8-oxo-dA), a well-known oxidatively induced DNA damage lesion and base excision repair (BER) substrate. The collected data indicate that MCF-7 and MDA-MB-231 breast cancer cells are highly susceptible to radiation-induced DNA damage, being mainly defective in the repair of these lesions. [ABSTRACT FROM PUBLISHER]

We study the electron spin decoherence of encapsulated atomic hydrogen in octasilsesquioxane cages induced by the 1H and 29Si nuclear spin bath. By applying the Carr–Purcell–Meiboom–Gill (CPMG) pulse sequence we significantly suppress the low-frequency noise due to nuclear spin flip-flops up to the point where a maximum T2 = 56 μs is observed. Moreover, dynamical decoupling with the CPMG sequence reveals the existence of two other sources of decoherence: first, a classical magnetic field noise imposed by the 1H nuclear spins of the cage organic substituents, which can be described by a virtual fluctuating magnetic field with the proton Larmor frequency, and second, decoherence due to anisotropic hyperfine coupling between the electron and the inner 29Si spins of the cage. [ABSTRACT FROM AUTHOR]

Purpose – The purpose of this paper is to focus on the corrosion protection of magnesium alloy ZK10 by applying via the dip-coating process an hybrid organic-inorganic coating that contains nanocontainers of TiO2 loaded with corrosion inhibitor. Design/methodology/approach – The coating consists of cross-linked polymers containing epoxy groups, conductive polymer polypyrrole as well as organic modified silicates. The morphology and the composition of the coating were examined with scanning electron microscopy and energy dispersive X-ray analysis, respectively. Findings – Corrosion tests via electrochemical impedance spectroscopy denoted that the incorporation of loaded nanocontainers improved the anticorrosion properties of the coating by increasing the impedance values in the low frequency range. Moreover, the surface of the aforementioned coating remained crack free after the exposure of the sample to corrosive environment. Originality/value – The paper presents a new system which has been developed for the corrosion protection of magnesium alloy ZK10. [ABSTRACT FROM AUTHOR]

Temperature and pH responsive poly( N-isopropylacrylamide- co-methacrylic acid) (P(NIPAAm- co-MAA)) microcontainers with encapsulated magnetic nanoparticles in the shell were prepared by a two-stage distillation precipitation polymerization. PMAA@Fe3O4/P(NIPAAm- co-MAA) core-shell nanoparticles were synthesized by the second-stage polymerization of NIPAAm, MAA and N, N′-methylenebisacrylamide as crosslinker in the presence of magnetic nanoparticles and PMAA as core. These novel triple-functional microcontainers were prepared by selective removal of the PMAA core in water. Daunorubicin hydrochloride (DNR) was loaded into the microcontainers and the release profile was studied by UV-visible spectroscopy. The synthesized nanostructures were characterized with transmission and scanning electron microscopy, X-ray diffraction and Fourier transform infrared spectroscopy. The magnetic properties were evaluated by vibrating sample magnetometry. The shrink and swelling behavior was studied by dynamic light scattering. Copyright © 2012 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

Cerium titanium oxide nanocontainers were synthesized through a two-step process and then loaded with corrosion inhibitors 2-mercaptobenzothiazole (2-MB) and 8-hydroxyquinoline (8-HQ). First, polystyrene nanospheres (PS) were produced using polymerization in suspension. Second, the PS spheres were coated via the sol-gel method to form a cerium titanium oxide layer. Finally, the nanocontainers were made by calcination of the coated PS nanospheres. The size of the containers was 180 ± 10 nm as determined by Scanning Electron Microscopy (SEM). X-Ray Diffraction Analysis (XRD) showed that the nanocontainers consist of anatase and cerianite crystalline phases. The presence and loading of the inhibitors in the nanocontainers was confirmed with Fourier Transform Infrared Spectroscopy (FT-IR) and Thermo Gravimetric Analysis (TGA), respectively. TGA revealed the amount of 10.43 and 4.61% w/w for 2-MB and 8-HQ in the nanocontainers, respectively. Furthermore, the release kinetics of the inhibitors from the nanocontainers was studied in corrosive environment using electrochemical impedance spectroscopy (EIS) in the presence of aluminum alloys 2024-T3 (AA2024-T3). [ABSTRACT FROM AUTHOR]

Cerium molybdate nanocontainers were synthesized using a two-step process and then loaded with 8-hydroxyquinoline (8-HQ) or with 1-H-benzotriazole-4-sulfonic acid (1-BSA). First, polystyrene (PS) nanospheres were produced using emulsion polymerization. Second, the PS spheres were coated via the sol–gel method to form a cerium molybdate layer. Finally, the nanocontainers were made by calcination of cerium molybdate coated PS nanospheres. The products were characterized by scanning electron microscopy (SEM/EDX), transmission electron microscopy, FT-infrared (FT-IR) spectroscopy, X-ray diffraction, thermogravimetric analysis (TGA), and differential thermal analysis. Moreover, nanocontainers were loaded with 8-HQ or with 1-BSA and their presence was confirmed with FT-IR. The loading of the inhibitors in the nanocontainers was estimated with TGA. The loading amount of 8-HQ was 5.22% w/w and that of 1-BSA was 16.43%. Based on the size of the nanocontainers and the assumption that they are not broken, we deduced to the amount of approximately with 1.07 × 106 molecules of 8-HQ and 2.35 × 106 molecules of 1-BSA per nanocontainer. Furthermore, release of 8-HQ or 1-BSA in corrosive environment was studied by potentiodynamic measurements for aluminum alloys 2024-T3 (AA2024-T3) and DC01 carbon steel (DC01-CS) samples, showing that the inhibitors are released from the nanocontainers, suppressing the corrosion activities. SEM photographs confirmed that the nanocontainers maintained their shape after suspension in 0.5 M NaCl solution for more than 72 h. Moreover, release of 8-HQ or 1-BSA in water was studied using spectrophotometer. [ABSTRACT FROM AUTHOR]

Magnetic hollow spheres were synthesized through a two-step process and were evaluated by Fourier transform infrared spectroscopy, scanning electron microscopy, super quantum interference device, vibrating sample magnetometry and Mössbauer spectroscopy methods. First, polystyrene spheres (PS) were produced using emulsion polymerization. Second, the PS spheres were coated via the sol–gel method to form an iron oxide layer. The size of the PS spheres was controlled by the concentration of the monomer (styrene), the initiator (potassium persulfate), and the emulsifier (sodium dodecylsulfate). The sol–gel coatings were prepared by controlled hydrolysis of aqueous solutions of FeCl3 in the presence of PS latex, polyvinylpyrrolidone, and hydrochloric acid. The composite was treated in air to burn off the PS latex. Temperature treatments were optimized after extensive differential thermal analysis and thermo gravimetric analysis characterization of the samples. Treatments under hydrogen atmosphere at various temperatures gave control over the formation and extend of magnetic phases in the nanocontainers such as a Fe, hematite (Fe2O3), and magnetite (Fe3O4). The size of the containers ranged between 300 and 400 nm. [ABSTRACT FROM AUTHOR]

Hollow ceria nanospheres were synthesized using anionic polystyrene lattices which were prepared by emulsion polymerization of styrene using potassium persulfate as the initiator. These anionic colloidal particles were dispersed in water in the presence of poly(vinylpyrrolidone) and mixed with aqueous solutions of cerium (III) acetylacetonate [Ce(acac)3]. Subsequently, hollow nanospheres of cerium compounds were obtained by calcination of the coated polystyrene lattices at an elevated temperature in air. The hollow ceria nanospheres were characterized by scanning electron microscopy, transmission electron microscopy, Fourier transform infrared spectroscopy, X-ray diffraction, thermogravimetric analysis, and differential thermal analysis. The hollow ceria nanospheres were coated with conductive polymers (polyaniline and polypyrrole) via an electropolymerization process. Moreover, the antibacterial action of illuminated hollow ceria nanospheres and hollow ceria nanospheres coated with conductive polymers (CPCeO2) on a pure culture of Escherichia coli was studied. A decrease of E. coli concentration was observed after illumination of bacteria in the presence of hollow ceria nanospheres and CPCeO2. [ABSTRACT FROM AUTHOR]

Nanoscale drug delivery systems represent a promising strategy to treat cancer and to overcome the side effects of chemotherapy. In particular, hollow polymeric nanocontainers have attracted great interest because of their structural and morphological advantages and the variety of polymers that can be used, allowing the synthesis of stimuli-responsive materials capable of responding to the biochemical alterations of the tumour microenvironment. Here are reported the synthesis, characterization and in vitro evaluation of a three-stimuli-sensitive hollow nanocontainer consisting of three different shells, each one sensitive to a specific tumoral stimulus: in order pH, temperature and reducing environment. To test its properties, daunorubicin was used as a model drug, for which the nanocontainers exhibited excellent encapsulation ability. The in vitro drug release behaviour was studied under different conditions, where the system proved capable of responding to the selected tumoral stimuli by releasing a larger amount of drug than in physiological environment. The hollow system itself showed negligible cytotoxicity but the loaded nanocontainers and free drug showed identical cytotoxicity and intracellular localization. Therefore, this formulation can be considered as a promising platform to develop an injectable delivery system capable of improving systematic toxicity without affecting or reducing the activity of the encapsulated drug. [ABSTRACT FROM AUTHOR]