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It is known that Schiff bases and their metal complexes have many properties in different biological systems and this varies with its structural properties. This paper has described the method for synthesis of Schiff base ligand (SB1) and derived Co (II) complex of this ligand. The synthesized metal complex is characterized by X‐ray diffraction (XRD), field emission scanning electron microscope (FE‐SEM), and Fourier‐transform infrared spectroscopy (FTIR). XRD shows the crystalline state of the complex and Schiff base as well as FE‐SEM shows the surface morphology and FTIR is used to characterize functional groups, bonding types, and nature of complex. [ABSTRACT FROM AUTHOR]

In the present investigation, the cellulose fibers were extracted from Arundo donax through a three‐step treatment. The effects of the alkaline pre‐treatment, acid hydrolysis, and soxhlet‐based extraction on the qualitative and quantitative attributes of the resultant cellulose fibers were investigated. The results of the present study signify a positive correlation between chemical treatment and cellulose content. The overall yield conversion of cellulose was recorded as 156.67%, after Soxhlet‐based purification. It was also observed that the moisture content, percentage of water absorption, rate of water absorption, and ash mass fraction gradually declined after each treatment step. The correlation between the chemical treatment with quantitative and qualitative attributes revealed a gradual increment in cellulose content, crystallinity index, and purity of cellulose fiber extracted from A. donax. The FTIR spectra emphasized that the obtained cellulose was free from impurities after Soxhlet‐based extraction. Simultaneously the DTG curve of A. donax fiber revealed a low rate of derivatization in the fibers extracted after Soxhlet treatment. The SEM and EDX analysis illustrate that the cellulose fibers were devoid of impurities as well as contamination of heavy metal ions. [ABSTRACT FROM AUTHOR]

Background: Platelet‐rich fibrin (PRF) is a second‐generation platelet concentrate with multiple applications in wound healing and regeneration in both periodontitis and diabetes. However, the three dimensional (3‐D) structure and cytokine content of PRF might be altered in patients suffering from either/both of the chronic inflammatory conditions, ultimately influencing the efficacy of PRF as a biomaterial for regenerative medicine. Aim: The aim of the present study was hence to evaluate the effect of both these chronic inflammatory diseases on the 3‐D structure of PRF membrane. An attempt was also made to compare the growth factor content between the plasma and RBC ends of the prepared PRF gel. Materials & Methods: L‐PRF was prepared for twenty participants, healthy (5), periodontitis (5), T2DM (5) and T2DM with periodontitis (5). Porosity and fiber diameter of PRF membranes was visualized under FE‐SEM and measured using ImageJ Software. PDGF‐BB and TGF‐β1 levels in PRF gel were assessed by ELISA. Results: The average diameter of fibrin fibers under FE‐SEM was 0.15 to 0.30 micrometers. Porosity was higher at the plasma end (p = 0.042). Red blood cell (RBC) end of the membrane had thinner fibers arranged in a comparatively more dense and compact structure with smaller porosities. Healthy subjects had the least porous PRF compared to subjects with either/both of the chronic conditions. PDGF‐BB levels were similar along all the four groups. TGF‐β1 levels were highest in healthy subjects. Discussion: 3‐D structure and growth factor content of PRF are influenced by a person's periodontal and/or diabetic status. The RBC end of the PRF membrane, as compared to the plasma end, has thinner fibers arranged in a comparatively more dense and compact structure with smaller porosities, and hence should be favored during periodontal regenerative procedures. Conclusion: Both periodontitis and diabetes have a significant influence on the 3‐D structure and growth factor content of PRF produced. [ABSTRACT FROM AUTHOR]

Poly(lactic acid) gels formed from solutions of poly(L‐lactic acid) (PLLA) and poly(D‐lactic acid) (PDLA). X‐ray diffraction patters indicate the formation of stereocomplex crystals for not only the gel formed from solution containing equimolar PLLA and PDLA, but also the gel formed from solution containing 9:1 of PLLA and PDLA. The flow temperatures of the gels were determined by viscoelastic measurements, and the morphologies of the dried gels were observed by field emission scanning electron microscopy. The flow temperatures of the gels from solutions containing both PLLA and PDLA were higher than those containing only PLLA. Network structures formed by uniformly distributed thin fibers, were observed for the gels formed from solutions with L:D ratios near the equimolar ratio. The dependency of the flow temperature and morphology on the polymer concentration and L:D ratio of the gels was discussed based on the experimental data. [ABSTRACT FROM AUTHOR]

Peucedanum miroense K. Kim, H.‐J. Suh & J.‐H. Song, recently reported as a new species endemic to South Korea, is distributed on mountains Duta‐san and Swinŭm‐san in Gangwon Province, South Korea. Given its conspicuously limited habitat range and small populations, this species qualifies as an endangered Red List species. In this study, we undertook a detailed investigation of the floral micromorphological, palynological, and carpological characters of P. miroense based on a range of microscopic analyses. Examination of the floral micromorphology of P. miroense revealed that the surface patterns of bractlets have potential utility in taxonomy studies of the genus Peucedanum. In addition, we established that this plant is characterized a papillose conical‐tabular rugose pattern of petal epidermal cells and bears sunken nectary slits on the stylopodium. Also identified were simple spherical orbicules bearing psilate surface ornamentation, as well as small tricolporate prolate to perprolate pollen grains characterized by verrucate and gemmate ornamentation. Moreover, we verified pollen wall stratification and presence of pollenkitt. The mericarps had colliculate‐striate surface patterns with trichomes and eight or nine vittae, and prismatic crystals were detected in different layers of the pericarp. We believe that the findings of this study will contribute to an evaluation of the taxonomic significance of this species within the genus Peucedanum, and also provide valuable information for the conservation of this rare endemic species. Research Highlights: We provided the first detailed descriptions of the floral micromorphological, palynological, and carpological characters of the rare endemic Korean species Peucedanum miroense K. Kim, H.‐J. Suh & J.‐H. Song, based on different microscopic analyses.Our findings provide valuable information regarding the epidermal cell patterns of bractlets, petals, stylopodium, gynoecium, and anthers.We believe our study makes a significant contribution to the literature, as our findings will contribute to enhancing the taxonomical classification of species within the genus Peucedanum, and will provide a basis for the conservation of this rare endemic species.This results will be of value to researchers studying the future biology and taxonomy of species within the family Apiaceae, particularly those using different microscopic techniques, including FE‐SEM, digital slide scanning, and TEM. [ABSTRACT FROM AUTHOR]

Microplastic pollution is a serious threat to the biota and humans, and wastewater treatment plants act as a pathway for entering microplastics into the environment. This study discusses the identification and quantification of microplastics in the south of Tehran municipal WWTP. The sampling was repeated three times in a month, overall, nine times for water samples and once a month in total, three times for digested sludge samples by steel bucket with the WPO method. The microplastics from water and digested sludge samples were identified using the micro‐Raman microscope. According to this study, 98.9% of microplastic particles in effluent and 99.2% of microplastics particles in the sludge were fibers. The influent contained an average of 180 ± 4.3 MP/L and was reduced to 5.3 ± 0.31 MP/L in the final effluent. Despite this significant reduction, we calculate that this WWTP releases 2.3 × 109 microplastics per day through final effluent and 1.61 × 1010 particles per day through dried sludge into the environment. We performed micro‐Raman analyses and ICP mass to measure the amount of heavy metal absorption of MPs. In addition, SEM analyses were used to study the surface morphology of microplastic particles. Practitioner Points: Fourteen different polymers were identified in the influent, effluent, and digested sludge.The main collected shapes obtained were fiber, film, and fragment, which fiber was the predominant polymer in this WWTP.The plant releases 2.3 * 109 MPs per day to its downstream environment.This WWTP has average removal with an efficiency of 99.06%. [ABSTRACT FROM AUTHOR]

Herein, an attempt has been made to synthesize silver nanoparticles from Murraya koenigii leaf extract at room temperature. The synthesized materials are stable for several months. The UV‐vis spectrophotometric analysis is carried out to ensure the formation of silver nanomaterials. XRD pattern confirms the formation of polycrystalline silver nanomaterials with the cubic crystal structure. Irregularly shaped particles are observed under field emission scanning electron microscopic observations. Elemental studies show the presence of Ag and O elements. The synthesized nanomaterial is multi‐applicative and shows potential efficacy against pathogenic microorganisms like Pseudomonas aeruginasa and Staphylococcus aureus. The results show that the leaf extract of M. koenigii is an efficient bio‐reductant for the synthesis of silver nanomaterials. The synthesized nanoparticles show potent anti‐microbial activities against Gram‐positive and Gram‐negative bacteria under study. [ABSTRACT FROM AUTHOR]

Advanced polycrystalline ceramics are gaining importance on development of light‐emitting diodes, infrared detectors, solid‐state lasers, etc. The physical properties of these materials are dependent on variety of dopant concentrations. In this manuscript, we have synthesized Yb‐doped Y2O3 (Y2‐xYbxO3) (x = 0.0, 0.02, 0.06, 0.1, 0.14) nanoparticles using co‐precipitation method. X‐ray diffraction patterns confirm the presence of cubic phase for pure Y2O3 nanoparticles and mixed phase (cubic + monoclinic) for Yb‐doped Y2O3 nanoparticles. The average crystallite size is found in the range 71 to 31 nm and lattice strain −1 × 10−4 to‐5 × 10−4 calculated using Debye‐Scherrer formula and Willimission‐Hall plot. The crystallite size decrease with dopant concentration upto x = 0.10 and material is found to exhibit compressive lattice strain. Field‐emission scanning electron microscopy shows agglomerated nanoparticles. The Fourier‐transform infrared spectroscopy confirms the presence of metal oxide functional groups (Y‐O and Yb‐O) and vibrational bands corresponding to O‐H vibration, C‐O bending, and stretching modes in the samples. The band gap energy (Eg) is found to decrease from 5.14 eV for x = 0.0 to 3.60 eV for x = 0.14 composition. The photolumincence spectra show characteristic blue and green emission at 486 nm for x = 0.10 and 525 nm for x = 0.0, respectively. The frequency‐dependent dielectric studies confirm the enhancement in dielectric constant with increase in Yb doping. These structural, morphological, optical, and electrical properties of Yb:Y2O3 nanoparticles are helpful for selecting this material as an appropriate candidate for laser host material for medical imaging and display devices applications. [ABSTRACT FROM AUTHOR]

The present study investigates the effect of halloysite clay nanotubes (HCNTS) on the mechanical properties of glass reinforced aluminum laminate (GLARE) as a very popular fiber metal laminate (FML). GLARE (3/2) with quasi‐isotropic lay‐up, [Al/[(0°/90°)/(45°/−45°)]s/Al/[(0°/90°)/(45°/−45°)]s/Al], filled with different wt% ofHCNTs (0, 0.25, 0.5, 1, 2, and 3 wt%) were fabricated using hand lay‐up followed by compression molding. Tensile, flexural, and impact properties of the fabricated GLAREs were evaluated. The failure of the specimens was examined using field emissionscanning electron microscope (FE‐SEM), energy‐dispersive X‐ray spectroscopy (EDX) and visual inspection. Test results demonstrated that the incorporation of HCNTs improves the mechanical properties of GLARE. Among the studied wt%, the inclusion of 1 wt% of HCNTs to GLARE leads to maximum improvements of 35.67%, 8.50%, 28.85%, 50.47%, 50.27%, 30.43%, and 51.52% in tensile strength, tensile strain, Young's modulus, modulus of toughness, flexural strength, flexural strain, and impact strength, respectively, was attained by adding 1 wt% of HCNTs to GLARE compared to pristine GLARE. Meanwhile, increasing HCNTS content to 3 wt% reverse the trend. FESEM showed that, HCNTS are well dispersed in epoxy. However, a higher weight fraction of HCNTS in epoxy, that is, 3 wt% leads little agglomerations. [ABSTRACT FROM AUTHOR]

The organic‐rich shale of the Shanxi and Taiyuan Formation of the Lower Permian deposited in a marine‐continental transitional environment are well developed in the Ordos Basin, NW China, which is considered to contain a large amount of shale hydrocarbon resources. This study takes the Lower Permian Shanxi and Taiyuan shale collected from well SL# in the Ordos Basin, NW China as an example to characterize the transitional shale reservoir. Based on organic geochemistry data, X‐ray diffraction (XRD) analysis, field‐emission scanning electron microscopy (FE‐SEM) observations, the desorbed gas contents of this transitional shale were systematically studied and the shale gas potential was investigated. The results indicate that the Lower Permian Shanxi and Taiyuan shale has a relatively high total organic carbon (TOC) (average TOC of 4.9%) and contains type III kerogen with a high mature to over mature status. XRD analyses show that an important characteristic of the shale is that clay and brittle minerals of detrital origin comprise the major mineral composition of the marine‐continental transitional shale samples, while the percentages of carbonate minerals, pyrite and siderite are relatively small. FE‐SEM observations reveal that the mineral matrix pores are the most abundant in the Lower Permian shale samples, while organic matter (OM) pores are rarely developed. Experimental analysis suggests that the mineral compositions mainly govern the macropore development in the marine‐continental transitional shale, and mineral matrix pores and microfractures are considered to provide space for gas storage and migration. In addition, the desorption experiments demonstrated that the marine‐continental transitional shale in the Ordos Basin has a significantly potential for shale gas exploration, ranging from 0.53 to 2.86 m3/t with an average value of 1.25m3/t, which is in close proximity to those of terrestrial shale (1.29 m3/t) and marine shale (1.28 m3/t). In summary, these results demonstrated that the Lower Permian marine‐continental transitional shale in the Ordos Basin has a significantly potential for shale gas exploration. [ABSTRACT FROM AUTHOR]

To increase efficiencies of bifacial solar cells, emitter, back surface field (BSF), and metal patterns must be optimized. We study the influence of paste volume, through multiple prints, of two silver pastes on the contact formation at the rear side of n‐type passivated emitter and rear totally diffused (n‐PERT) solar cells with two BSF doping profiles. Differences in fingers' electrical properties were found between pastes. Contact resistivity shows a relative difference of 27.6%, partially explained by changes in the silver crystallites formation at the Ag/Si interface and in the crystallites' penetration depth. Variations in crystallites formation and penetration between pastes can reach 38.4% and 48.8%, respectively. Line resistance shows a difference between pastes, appearing as the main cause of an absolute efficiency difference of 2.9%. Fingers' structural and electrical properties are modified by increasing the paste volume. Microstructure analysis reveals that additional metallic printing does not only increase line cross sectional area but also increases the formation of silver crystallites, which can reach a relative increment of 23.9% between first and second prints. Further printing does not necessarily decrease contact resistivity, but reduces line resistance in up to 94.9%, which results in an absolute efficiency increase of 2.2%. In addition, the higher presence of silver oxide in the finger is related to a higher efficiency in the formation of silver crystallites. Finally, BSF doping has an influence in the open circuit voltage, short circuit current density, and contact resistivity, with differences that can reach 8.7 mV, 0.2 mA/cm2, and 6.1 mΩcm2, respectively, depending on paste and number of prints. [ABSTRACT FROM AUTHOR]

In this study, the synthesis of ultra‐fine grade antimony trioxide (Sb2 O3) using plant extract for the first time is reported. Antimony chloride was used as a starting material and Dioscorea alata tuber extract was used as a reducing and capping agent. The synthesised nanoparticles were characterised by X‐ray diffraction (XRD), field emission scanning electron microscopy (FE‐SEM), dynamic light scattering (DLS), and Fourier transform infrared spectroscopy. XRD analysis indicates the formation of pure Sb2 O3 nanoparticles. The result from FE‐SEM and DLS showed that the particles have a cube‐like morphology and have an average size of 346.4 nm which falls within the range of ultra‐fine grade Sb2 O3. [ABSTRACT FROM AUTHOR]

Nanoscale pore characteristics of the Upper Permian Longtan transitional mudrocks and their equivalent strata Wujiaping Formation marine mudrocks in and around the eastern Sichuan Basin was investigated using field emission scanning electron microscopy (FE‐SEM) and low‐pressure N2 adsorption experiments. The results indicate that the Upper Permian mudrock is at a mature stage with total organic carbon (TOC) values ranging between 0.47% and 12.3%. The Longtan mudrocks mainly contain vitrinite, and their mineral composition is primarily clay. In contrast, the Wujiaping mudrocks are dominated by sapropelinite and solid bitumen, and their mineral compositions are mainly quartz and a notably high amount of pyrite. The FE‐SEM reveals that clay mineral pores and microcracks are the common pore types in the Longtan mudrocks. The specific surface area and pore volume depend on the clay content but are negatively correlated with the TOC. The generation of nanometer pores in the Longtan mudrocks is caused by high clay mineral contents. Meanwhile, the Wujiaping mudrock mainly contains OM pores, and the pore parameters are positively correlated with the TOC. The OM pore development exhibits remarkable differences in the Longtan and Wujiaping mudrocks, which might be related to their sedimentary facies and maceral fractions. Vitrinite and inertinite appear as discrete particles in these mudrocks and cannot generate pores during thermal maturation. Sapropelinite often contains many secondary pores, and solid bitumen with large particles, usually with several pores, is not the major contributor to the pore system of the investigated mudrock. [ABSTRACT FROM AUTHOR]

This work investigated the element distribution of perthite from the Upper Triassic Yanchang Formation tight sandstone in the Ordos Basin of northern China by field emission scanning electron microscopy (FE‐SEM) and energy dispersive spectrometer (EDS). FE‐SEM results indicate significant differences in the morphology of Na‐rich feldspar when K‐rich feldspar is the main component of the perthite. EDS results show that different types of perthite have clearly defined differences on different element indexes. Additionally, indexes such as average‐weight‐K (K‐rich)/Na (Na‐rich), maximum‐weight‐K (Na‐rich)/Na (Na‐rich) and average‐atomic‐K (K‐rich)/Na(Na‐rich) might be the most effective ones to identify perthite types. Perthite is divided into six main types, i.e., perthite with thick parallel stripe distribution, with thin parallel stripe distribution, with lumpy stripe distribution, with dendritic stripe distribution, with encircling stripe distribution, and with mixed stripe distribution. [ABSTRACT FROM AUTHOR]

Fabrication of polymer-carbon composite nanostructure with good dispersion of each other is critical for the desired application due to the nanostructure flaws, agglomeration, and poor absorption between the 2 materials. Fabrication of superhydrophobic surface coating composites of polytetrafluoroethylene (PTFE) with multiwalled carbon nanotubes (MWCNTs) through supercritical fluid processing was explored in this study. Homogeneity of the composite was characterized by X-ray diffraction and Raman spectroscopy studies, which reveal that the PTFE and MWCNT are uniform in the composite. Microstructural surface evaluation of field-emission scanning electron microscope and high-resolution transmission electron microscope studies display that the coating composite possesses roughness structures and fibrillation of the superhydrophobic surface coating. Superhydrophobic character was evaluated on fiber-reinforced plastic (FRP) sheets, which showed that the prepared coating composite surface showed self-cleaning properties with a high water contact angle of 162.7°. The surface wettability was studied by increasing different temperatures (30°C to 300°C) in PTFE-MWCNT composite, which reveals that the FRP sheets were thermally stable up to 200°C and afterward; they transformed from superhydrophobic to hydrophilic state at 250°C. The superhydrophobic surfaces are thermally stable in extreme environmental conditions, and this technique may be used and extendable for large-scale applications. [ABSTRACT FROM AUTHOR]

Abstract: In this article Ca1‐xTiO3:xEu3+ single crystalline particles with a cubic morphology and average size of 248 to 815 nm were synthesized by a solvothermal method. The structural and optical properties of the Ca1‐xTiO3:xEu3+ cubes were investigated, the formation mechanism of the cubes were analyzed and discussed, and the influence of Eu doping content and cubic size on the photoluminescence were examined. The differences in the photoluminescence between Ca1‐xTiO3:xEu3+ cubic crystals and nanoparticles was analyzed. It was found that an addition of a small amount of water can substantially reduce the size of the cubes. An obvious red emission band centered at 615 nm was observed under the excitation at 395 nm for the cubes. Our results demonstrate CaTiO3 cubes are good host materials for designing red phosphors. [ABSTRACT FROM AUTHOR]

The tea green leafhopper, Empoasca onukii Matsuda ( Hemiptera: Cicadellidae: Typhlocybinae), is a serious pest of tea plants in East Asia. Previous work has shown that two tea germplasms, Cd19 and Cd289, sustain less hopperburn damage by E. onukii than does Camellia sinensis (L.) O. Kuntze cv. 'Yabukita' (Theaceae), and E. onukii excretes less honeydew on these germplasms than on the susceptible Yabukita. This study investigated the feeding behavior of E. onukii with a direct current electropenetrograph ( DC EPG) to compare feeding behaviors, including ingestion, on resistant tea germplasms and Yabukita. Feeding behaviors on the resistant germplasms were significantly restricted, with few bouts of active ingestion of short duration and long periods of non-probing, whereas E. onukii engaged in active ingestion of long duration many times on the susceptible cv. Yabukita. The tea germplasms, Cd19 and Cd289, therefore showed strong resistance to E. onukii. Furthermore, the shape of puncture holes left after probing was compared between the susceptible Yabukita and the resistant germplasms. The puncture holes on Cd19 and Cd289 were indistinct in shape and closed compared with those on Yabukita. [ABSTRACT FROM AUTHOR]

ABSTRACT Nanoarchitecture of cured urea-formaldehyde (UF) resins was examined with a field-emission scanning electron microscope (FE-SEM) after coating samples with osmium, which is considered to produce particles of considerably smaller size compared to other metal coatings used in SEM studies. This method enabled comparison of the nanoarchitecture of UF resins of low (1.0) and high (1.6) formaldehyde/urea (F/U) mole ratios to be made, based on imaging of extremely small size particles as part of UF resin architecture, not described before. Imaging revealed presence of relatively large globular particles (148.084-703.983 nm size range) as well as smaller substructures (28.004-39.604 nm size range) as part of the architecture of 1.0-mole UF resin. Globular particles were also present in 1.6 mole UF resin, but of considerably smaller size (14.760-50.269 nm). The work presented demonstrates usefulness of osmium coating in unraveling the intricacies of the nanostructural organization of cured UF resins, prompting wider application of this immensely useful but grossly underutilized metal coating type in high resolution SEM examination of biological and materials samples. Microsc. Res. Tech. 76:1108-1111, 2013. © 2013 Wiley Periodicals, Inc. [ABSTRACT FROM AUTHOR]

Cell wall deterioration throughout enzymatic hydrolysis of cellulosic biomass is greatly affected by the chemical composition and the ultrastructure of the fiber cell wall. The resulting pattern of cell wall deterioration will reveal information on cellulose activity throughout enzymatic hydrolysis. This study investigates the progression and morphological changes in lignocellulose fibers throughout enzymatic hydrolysis, using (transmission electron microscopy) TEM and field emission scanning electron microscopy (FE-SEM). Softwood thermo-mechanical pulp (STMP) and softwood bleached kraft pulp (SBKP), lignocellulose substrates containing almost all the original fiber composition, and with lignin and some hemicellulose removed, respectively, was compared for morphology changes throughout hydrolysis. The difference of conversion between STMP and SBKP after 48 h of enzymatic hydrolysis is 11 and 88%, respectively. TEM images revealed an even fiber cell wall cross section density, with uneven middle lamella coverage in STMP fibers. SKBP fibers exhibited some spaces between cell wall and lamella layers due to the removal of lignin and some hemicellulose. After 1 h hydrolysis in SBKP fibers, there were more changes in the fiber cross-sectional area than after 10 h hydrolysis in STMP fibers. Cell wall degradation was uneven, and originated in accessible cellulose throughout the fiber cell wall. FE-SEM images illustrated more morphology changes in SBKP fibers than STMP fibers. Enzymatic action of STMP fiber resulted in a smoother fiber surface, along with fiber peeling and the formation of ribbon-disjunction layers. SBKP fibers exhibited structural changes such as fiber erosion, fiber cutting, and fiber splitting throughout enzymatic hydrolysis. © 2012 American Institute of Chemical Engineers Biotechnol. Prog., 2012 [ABSTRACT FROM AUTHOR]

Several advanced high strength steels were intercritically annealed at a dew point of −5°C. Afterwards, surface morphology was investigated by scanning and transmission electron microscopy (TEM). In Al alloyed TRIP-aided steels, nodules of metallic Fe containing traces of Mn could be proven by TEM analysis. To clarify the mechanism of origin, several further annealing trails were done and finally a new component of the occurring heterogeneous gas/metal reaction during intercritical annealing was postulated. It is concluded that neither the diffusion mechanism of the alloying elements nor the stress gradient between stress-free surface region of the internal oxidation front nor the oxygen partial pressure dominates alone the selective oxidation process. It is suggested that the reactivity of the considered surface, its local surface chemistry and the local thermodynamic equilibrium should be taken into account in greater detail. Preferred dissociation points of absorbed water vapor could lead to a local increased oxygen partial pressure. With this, a nanoscaled oxidation/reduction process could be initiated. [ABSTRACT FROM AUTHOR]

Benzotriazole (BTA) is an inhibitor molecule, commonly used to protect copper and copper-based archaeological artefacts from degradation processes such as the 'bronze disease'. The aim of the present work was to study in details the inhibition mechanism of the BTA molecule on pure copper and copper-tin alloy (called CNR 128) by the surface-sensitive techniques (field emission SEM with energy-dispersive X-ray spectrometer and XPS). To perform this investigation, the typical corrosion products of the patina, including cuprite (Cu2O) and atacamite (Cu2Cl(OH)3) compounds, were grown on pure copper and CNR 128 alloy. The BTA molecule was then applied on the surface of the prepared samples, following the method that is commonly used in the conservation of artefacts in cultural heritage. During the analyses of pure copper substrate, it was revealed by XPS that BTA molecule favours the formation of Cu(I) species, when it is adsorbed on an atacamite-enriched surface. On the contrary, when BTA molecule is adsorbed on a cuprite-enriched surface, it is promoted the formation of Cu(II) species. Instead, for degraded CNR 128 alloy where atacamite or cuprite were the main component of the patina, XPS results showed that the chemical nature of the bronze surface is present Cu(II) oxidation state. Copyright © 2012 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

The present work reports the results of the SEM-energy dispersive spectrometry, X-ray diffraction (XRD), XPS and optical microscopy (OM) investigations performed to identify the corrosion products nature, i.e. the patina, grown on bronze common use artefacts found during excavations carried out at Tharros (on the west coast of Sardinia, Italy). The micro-chemical investigations of the patina revealed the structure and the chemical composition of the stratified corrosion layers, where tin depletion phenomenon has been observed within some cases of a surface enrichment of lead combined with elements coming from the soil such as Cl and P and mixed with other burial elements such as Ca, Si, Fe, Si and Al. The presence of soil elements was also confirmed by XPS investigations that evidence from the lineshape analysis and Binding Energy (BE) values of Cu 2p, Sn 3 d and Pb 4f photoemission signals that these elements are mainly present in their maximum oxidation states on the surface. The surface information is confirmed by OM and XRD results that evidence also the presence of copper trihydroxychlorides. In the inner layers, OM, SEM-energy dispersive spectrometry and XRD results disclose the presence of Cu (I) compounds such as cuprite (Cu2O) and nantokite (CuCl), the latter being the specie that induces the cyclic and self-sustaining degradation process commonly defined 'bronze disease'. The micro-chemical and micro-structural informations demonstrate the strict interaction between soil components and corrosion products that form different compounds as a function of the local characteristics of the soil and of the chemical composition and metallurgical features of the Cu-based alloys. Copyright © 2012 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Fluoroalkyl end-capped acrylic acid, N, N-dimethylacrylamide, N-(1,1-dimethyl-3-oxobutyl)acrylamide and vinyltrimethoxysilane oligomers reacted with polyamic acid possessing trimethoxysilyl groups under alkaline conditions to yield the corresponding fluoroalkyl end-capped oligomers/polyamic acid/silica nanocomposites. These isolated fluorinated composite powders were found to afford nanometer size-controlled fine particles with a good dispersibility and stability in water and traditional organic solvents. We succeeded in preparing new fluoroalkyl end-capped oligomers/polyimide/silica nanocomposites by the imidization of fluorinated polyamic acid silica nanocomposites through the stepwise heating at 110 and 270°C under air atmosphere conditions. These fluorinated polyimide/silica nanocomposites thus obtained were applied to the surface modification of glass and poly(methyl methacrylate) (PMMA) to exhibit good hydro- and oleo-phobic characteristics imparted by fluoroalkyl groups in the composites on their surface. In addition, the surface morphology of the modified glass treated with these fluorinated nanocomposites were analyzed by using FE-SEM and DFM. Copyright © 2011 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

To use carbon nanotubes (CNTs) as anode material for the solid-state thin-film Li-ion rechargeable battery, the tubes are preferred to be aligned perpendicular to a substrate and the CNT thin film to have a smooth surface. Using an Ar-ion sputtering technique, we carried out the surface modifications of the CNT thin film prepared by the SiC surface decomposition method. In order to evaluate the surface modification, the surface and cross section of the modified CNT film were investigated by field-emission scanning electron microscopy and atomic force microscopy. © 2012 Institute of Electrical Engineers of Japan. Published by John Wiley & Sons, Inc. [ABSTRACT FROM AUTHOR]