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Pre-edge X-ray absorption features are commonly used to derive redox states for transition metal oxides in crystals and glasses. Several calibrations for Fe2+ and Fe3+ in silicate glasses have utilized the general relationships among pre-edge peak intensity, energy, and redox state. However, absorption variations complicate those relationships in anisotropic crystals. Although absorption anisotropy at and above the energy of the rising edge adheres to the typical cos2 relationship observed in absorption spectroscopies at other energies, the anisotropy of the pre-edge is far more complicated. Prior studies focusing on pre-edge absorption anisotropy demonstrate a 1-cos4φ dependence of absorption magnitudes with rotation. Experiments presented here show that absorption magnitudes of the pre-edge vary as a function of both electric field vector orientation and wave vector direction. However, rotations around the field vector axis or wave vector axis individually result in cos2 dependence of absorption magnitudes. Rotations where both wave vector and field vector orientation are varied are not well fit by either model in the pre-edge. The resulting anisotropy complicates the process of measuring characteristic absorption in the pre-edge, making valence state determinations challenging for strongly anisotropic crystal structures such as pyroxene. [ABSTRACT FROM AUTHOR]

Transition metal complexes (TMCs) with strong and long-lived excited state absorption (ESA) usually exhibit high-performance optical power limiting (OPL) response. Several techniques, such as transmission vs. incident fluence curves and Z-scan have been widely used to assess the OPL performance of typical TMCs. The OPL performance of TMCs is highly molecular structure-dependent. Special emphasis is placed on the structure-OPL response relationships of Pt(II), Ir(III), Ru(II), and other metal complexes. This review concludes with perspectives on the current status of OPL field, as well as opportunities that lie just beyond its frontier. [ABSTRACT FROM AUTHOR]

The optical properties (scattering, absorption, and extinction) of spheroidal Cu particles embedded in intermediate plagioclase feldspar are computed for various sizes and shapes using the Mie theory and T-matrix method. The observed color for Cu-bearing plagioclase, as a function of particle size and shape, is also calculated from the computed extinction spectra. The colors and pleochroism observed in natural and treated Cu-bearing plagioclase can be explained from the computational results. The enigmatic green colors in some precious Oregon sunstones result from red light being scattered away by Cu nanoparticles of certain sizes. The UV-VIS spectra are collected on Cu-bearing plagioclase samples for comparison with the computational results, which are shown to match the optical observations. The results from this work may be used to quantify the concentration of colloidal Cu in plagioclase or glass with a similar refractive index. Particle sizes and shapes can also be characterized using extinction and scattering spectra, which can be collected with different optical configurations. New materials with special color effects and optical characteristics may be designed and engineered by applying the unusual properties of metal colloids. [ABSTRACT FROM AUTHOR]

David Miall was, for many scholars, the person welcoming them into the field of empirical literary studies. The research he conducted together with Don Kuiken on the effects of stylistic features on reading, with a central role for (self-modifying) feeling (cf. Miall, David S. & Don Kuiken. 1994. Foregrounding, defamiliarization, and affect: Response to literary stories. Poetics 22(5). 389–407) has been the inspirational foundation for much of the research conducted in this and other fields, such as cognitive poetics. By combining methods from traditional literary reading (such as close reading), with methods more commonly used in psychology (such as experimental designs and self-report questionnaires), he gave new depth to the concept of reader response research (Whiteley, Sara & Patricia Canning. 2017. Reader response research in stylistics. Language and Literature 26(2). 71–87), concerning himself with actual readers' testimonials. In honour of David, this paper will present a close reading, not of a literary text, but of a particular reader testimonial, namely an online book review. By applying a close reading informed by Text World Theory, I attempt to show how the social context in which this review was written influenced the expression of narrative absorption the reader experienced during reading. Consequently, I argue for an expansion not just of the methodological toolbox we use to investigate absorption in online social reading, but for an expansion of the concept of story world absorption itself. [ABSTRACT FROM AUTHOR]

While wood substances that contain water have shown a dielectric effect, they have never been directly proposed as a microwave absorption material to reduce artificial electromagnetic pollution. In this study, the microwave absorption efficiency of wood that contains water was investigated based on its dielectric properties in the microwave frequency range to optimize the parameters of wood unit cells, including the orientation, moisture content (MC) and thickness. Subsequently, inspired by the design concept of electromagnetic metamaterials, single-layer wood unit cells containing moisture were directly integrated into double epoxy resin layers. This procedure formed a natural wood-based metamaterial (NWM) with a simple periodic Sandwich structure without the need for further chemical modification and/or high energy consuming processes. Such design strategies allowed the NWMs to overcome the limitation of inherent dielectric properties of natural wood and present significantly enhanced microwave absorption performance, as well as different absorption behavior. NWMs at a MC ≤ 70% displayed a selective absorption mode, while NWMs at MC ≥ 85% showed a broadband absorption mode. Both absorption modes could achieve the peak absorptivity > 98%. Particularly, the NWM in the broadband absorption mode possessed an effective absorption (absorptivity > 90%) bandwidth of 9.04 GHz, which was 7.6 times that of natural wood (1.19 GHz). The NWMs performed well when irradiated by microwaves with different angles and directions. Also, the thickness of NWMs was only 7 mm, allowing easy incorporation of the materials in engineering designs. The use of sustainable materials, impressive performance, high stability, practical thickness, and the facile and cost-effective production technique demonstrated NWMs with great potential in designing green buildings. [ABSTRACT FROM AUTHOR]

Anisotropic absorption in crystals is routinely observed in many spectroscopic methods and is recognized in visible light optics as pleochroism in crystalline materials. As with other spectroscopies, anisotropy in Fe K-edge X‑ray absorption spectroscopy (XAS) can serve both as an indicator of the general structural arrangement and as a conundrum in quantifying the proportions of absorbers in crystals. In materials containing multiple absorbers, observed anisotropies can typically be represented by a linear relationship between measured spectroscopic peak intensities and relative absorber concentrations. In this study, oriented XAS analysis of pyroxenes demonstrates that the macroscopic theory that describes visible light absorption anisotropy of triaxially anisotropic materials can also be applied to X‑ray absorption in pyroxenes, as long as the orientation and magnitude of the characteristic absorption vectors are known for each energy. Oriented single-crystal XAS analysis of pyroxenes also shows that the measured magnitude of characteristic absorption axes at a given orientation is energy-dependent and cannot be reproduced by linear combination of intermediate spectra. Although the macroscopic model describes a majority of the anisotropy, there is distinct discordance between the observed and interpolated spectra in the pre-edge between 7109 and 7115 eV, which is marked by spikes in RMSE/mean intensity ratio. Absorption indicatrices for samples analyzed in the visible and at X‑ray wavelengths are modeled with a three-dimensional (3D) pedal surface, which functions as an empirical way of interpolating between the observed absorption data. This surface only requires a maximum of three coefficients, and results from the summation of 3D lemniscates. An absorption indicatrix model can be used to characterize anisotropic absorption in crystals and provides a way of comparing XAS spectra from randomly oriented crystals, such as those from polished sections, to a database of characterized crystals. [ABSTRACT FROM AUTHOR]

To increase the emission intensity of Pr SP 3+ sp ions, Yb SP 3+ sp ions appear as an efficient sensitizer [[13]]. Due to a non-exponential character of the decay data, we have determined the experimental lifetime as being equal to the effective lifetime defined as HT ht Graph (4) Graph: Fig. [[36]]) HT ht Graph (5)where I i SB Pr-Yb sb and I i SB Pr sb are the effective lifetimes with and without Yb SP 3+ sp -coping, respectively, but for the same concentration of Pr SP 3+ sp ions. Emission spectra Emission spectra of Ln-doped samples TPr and TPrYb were measured in the same conditions allowing one to compare their relative intensities; additionally, in order to demonstrate the effect of the Pr SP 3+ sp ion concentration ( I N i SB Pr sb ; see Table 1) on the emission spectra, the PL signal of both samples (in arbitrary units) has been divided by I N i SB Pr sb . [Extracted from the article]

Carbon capture, utilisation, and storage (CCUS) is considered as the least cost-intensive option towards achieving the emission reduction target by 2050. One of the important technologies to remove CO2 from different gas streams is solvent-based CO2 capture. Modelling and simulation of solvent-based CO2 capture processes have been attracting a lot of attention in recent years. Thermodynamic models play a vital role in these modelling and simulation studies. Hence, this study critically reviews the thermodynamic models applied in the modelling of solvent-based CO2 capture systems over the past years, to provide a guideline for the selection of the optimum models for future studies. These models have wide applications in two main areas: equilibrium modelling [vapour-liquid equilibrium (VLE) (physical) and speciation equilibrium (chemical)], and calculation of some thermodynamic properties. VLE and speciation modelling methods are classified rigorously. VLE modelling methods are classified as homogeneous, heterogeneous, and empirical, and speciation modelling methods are classified as iterative (which could be stoichiometric and non-stoichiometric) and non-iterative. Thermodynamic models are categorised into three key families: activity-coefficient based, equation of state based, and quantum mechanical based. Theory and concepts of different thermodynamic models are presented. Some selected studies that used each family of thermodynamic models are reviewed. [ABSTRACT FROM AUTHOR]

In this note we study the probability and the mean time for absorption for discrete time Markov chains. In particular, we are interested in estimating the mean time for absorption when absorption is not certain and connect it with some other known results. Computing a suitable probability generating function, we are able to estimate the mean time for absorption when absorption is not certain giving some applications concerning the random walk. Furthermore, we investigate the probability for a Markov chain to reach a set A before reach B generalizing this result for a sequence of sets A1, A2, . . . , Ak. [ABSTRACT FROM AUTHOR]

This project originated more than 15 years ago with the intent to produce a glossary of drug metabolism terms having definitions especially applicable for use by practicing medicinal chemists. A first-draft version underwent extensive beta-testing that, fortuitously, engaged international audiences in a wide range of disciplines involved in drug discovery and development. It became clear that the inclusion of information to enhance discussions among this mix of participants would be even more valuable. The present version retains a chemical structure theme while expanding tutorial comments that aim to bridge the various perspectives that may arise during interdisciplinary communications about a given term. This glossary is intended to be educational for early stage researchers, as well as useful for investigators at various levels who participate on today's highly multidisciplinary, collaborative small molecule drug discovery teams. [ABSTRACT FROM AUTHOR]

Present work analyzes the behavior of several gas-liquid-liquid systems for carbon dioxide separation using chemical absorption. The type of amine center in a solvent with two liquid phases (organic and aqueous) shows a high importance in relation to the overall behavior. The experimental results for these solvents have been compared with a previous study using octylamine in the chemical solvent because it has shown suitable results for carbon dioxide loading, absorption rate and energy cost associated to solvent regeneration. Present study analyzes the carbon dioxide absorption mechanism in multiphasic reactors (specifically G-L-L) using different types of amines in order to understand the overall behavior that involves steps of mass transfer and chemical reaction. [ABSTRACT FROM AUTHOR]

In this article, we study about the absorption properties of terahertz (THz) wave in the magnetic plasma medium. Terahertz wave has strong transmission in plasma. Generally speaking, with the increase in THz wave frequency, the transmission in plasma is stronger. Thus, we can consider raising carrier frequency to THz band to solve the communication of "blackout." We found that the absorption in magnetic plasma is greatly affected by magnetic field. The changes on the power absorption coefficient of the two kinds of eigen wave in magnetic plasma vary with how the outside magnetic field, incident angle, and the thickness of the plasma are obtained. The study found that following the increase in magnetic field, the absorption of left circularly polarised waves (L-wave) gradually reduces, and the right circularly polarised waves (R-wave) will produce two absorption peaks, and these two absorption peaks move to high frequency as a whole. With the increase in incident angle and the high spectrum absorption of L-wave enhancement, the reflection between the two absorption peaks of R-wave broadens. The reflection area on the left side of the low-frequency area to absorb has a little change. The absorption on the right side of the high-frequency area is enhancement. With the increase in the plasma thickness, the L-wave absorption peak on the right side of the high-frequency area absorbs enhancement; the R-wave reflection between the two absorption peak areas is impregnability, the second absorption peak absorption enhancement on the right side of the high-frequency area. The study has shown the different absorption mechanisms of the L-wave and the R-wave and shown different absorption features in magnetic plasma. [ABSTRACT FROM AUTHOR]

Dissecting the inhibited variation of allergen absorption could contribute to the development of novel therapeutic or preventive treatments for food/feed allergies. This study investigated the effects of fructooligosaccharide (FOS) on the absorption, intracellular accumulation of intact or hydrolysed β-conglycinin in porcine intestinal epithelial cells (IPEC-J2). As demonstrated by ELISA and immunoblotting, β-conglycinin was absorbed in a dose- and time-dependent manner (p < 0.05). Actually, β-conglycinin was easily transported and absorbed after enzymatic hydrolysis. Three peptides (52 kDa, 30 kDa and 25 kDa) were produced during transcellular absorption of intact or hydrolysed β-conglycinin. FOS inhibited the absorption of β-conglycinin, especially the 52 and 30 kDa peptides. The immunoreactive peptides derived from the 52, 35 or 22 kDa peptides were the substrings of the known epitopes determined by mass spectrometry and bioinformatic analyses. These results indicate that FOS can efficiently inhibit the absorption of 52 and 30 kDa peptides derived from β-conglycinin. [ABSTRACT FROM AUTHOR]

Fine fibres (fines) occur at various stages of the papermaking process. The high specific surface of fines may be of special interest in applications beyond papermaking. In the present study, foamy water suspensions of fines were freeze-dried, and in this way their porous structure was maintained. The density and porosity of these foams could be governed by varying the water content of the suspensions. The obtained matrices were highly hydrophobic because of the sizing applied during the papermaking process. Consequently, a high oil sorption capacity of the fines was observed. Up to a porosity of 98%, more than 80% of the overall volume of the foam-like material could be soaked with liquid. At higher porosities, the absorbed volume decreased. Mechanical reinforcement of the foams with poly(methyl methacrylate) (PMMA) as accomplished by dip-coating had no negative impact on the sorption behaviour. However, the performance of reinforced samples suffered from strong shrinkage upon drying, especially for high porosity matrices. [ABSTRACT FROM AUTHOR]

High-resolution ultrasonic mechanical spectroscopy technique has been used to study the nature and dynamics of lattice defects and magnetic domain walls in the helical-type antiferromagnetic phase during thermal cycling of polycrystalline Dy samples between 80 and 210K. Effects of the lowest temperature of thermal cycles, applied magnetic field and cooling/ heating rate on the ultrasonic absorption and Young´s modulus have been investigated. A strong influence of cooling/heating rate on the ultrasonic absorption is found over the temperature range between the Néel temperature, ca. 178K, and approximately 145K, confirming the existence of a new category of magnetomechanical damping - transitory ultrasonic absorption related to translational motion of domain walls. A strong increase of the ultrasonic absorption below approximately 140K is attributed to the formation of nuclei of ferromagnetic phase, presumably stabilized by such lattice defects as dislocations. The effect of applied magnetic field on ultrasonic absorption also emerges below 140K and is ascribed to the appearance of the net magnetization due to ferromagnetic nuclei. We argue that these nuclei are responsible for the controversial thermal hysteresis of elastic and anelastic properties, which is strongly promoted by decreasing the temperature of thermal cycles. [ABSTRACT FROM AUTHOR]

A laser beam heats a mixture of ethanol and anthocyanins producing the effect of a reciprocating machine. This behaviour is analyzed in terms of the stable, metastable and unstable states of Landau and Lifschitz. Trying first with the van der Waals equation of state, with negative results because the system state is normally far from the critical state, a modified version, with van der Waals coefficients depending linearly on the temperature is proposed, based in the thermodynamic properties of ethanol at room and critical temperatures. The resulting theory allows us to understand the discontinuous results concerning the absorption of the laser beam in terms of a thermodynamic cycle and its frequency dependence on the laser light focus position. Slight changes in the experimental setup may enable the measurement of thermodynamic properties in metastable states. [ABSTRACT FROM AUTHOR]

Novel push-pull fluorescent dyes, 7-(diethylamino)furo[3,2-c]coumarin and 7-(diethylamino)thieno[3,2-c]coumarin derivatives, were designed and synthesized using formyl derivatives of furo- and thieno[3,2-c]coumarins as key intermediates. Electron absorption and emission spectra of the dyes were recorded in different solvents. The longest-wave bands in the electron absorption spectra of the dyes are suggested to be of push-pull nature. [ABSTRACT FROM AUTHOR]

This paper comprises two parts. We first investigate an Lp-type of limiting absorption principle for Schrödinger operators H = -Δ + V on ℝn (n ≥ 3), i.e., we prove the ε-uniform L2(n+1)/(n+3)-L2(n+1)/(n-1)-estimates of the resolvent (H - λ ± iε)-1 for all λ > 0 under the assumptions that the potential V belongs to some integrable spaces and a spectral condition of H at zero is satisfied. As applications, we establish a sharp Hörmander-type spectral multiplier theorem associated with Schrödinger operators H and deduce Lp-bounds of the corresponding Bochner-Riesz operators. Next, we consider the fractional Schrödinger operator H = (-Δ)α + V (0 < 2α < n) and prove a uniform Hardy-Littlewood-Sobolev inequality for (-Δ)α, which generalizes the corresponding result of Kenig-Ruiz-Sogge [20]. [ABSTRACT FROM AUTHOR]

In this paper, we first report effects of impact parameters on the oxidation property of photoinduced nitrate anion via degradation of multifarious colorants and indicators. While no degradation efficiencies are observed with respect to photoinduced nitrite instead of nitrate in the experiment. Several fundamental aspects regarding the effects of different structures of colorants, types of nitrate salt, illumination time and dosage of nitrate ion on the oxidation property were explored. The spectral evolution of UV-vis absorption was also investigated along with the degradation kinetics. Remarkably, this photoinduced nitrate ion played a major role in the fine oxidation property, and cations with greater extent of hydrolyzation would give rise to a more enhanced oxidation performance. The photodegradation of methyl orange and rhodamine B follows the zero-order and first-class dynamic equation, respectively. The maximum absorption peaks of dyes in visible light shifts towards shorter wavelengths as the illumination time increases. •OH radicals generated from photoinduced aqueous nitrate and •O2- originated from the reaction of •NO32- with dissolved oxygen were examined by EPR measurements, and they played a significant role in the photooxidation performance. This finding may provide new insights for treatment of industrial wastewater with good economic benefit and has potential application values in the field of photoreaction and photocatalysis. [ABSTRACT FROM AUTHOR]

Accelerated ageing is an often-used tool in conservation research, yet difficult to apply to parchment due to the materials inherent heat sensitivity. The complexity of this organic material makes the analysis of its deterioration especially challenging. An attempt to develop a non-heat ageing protocol for parchment is described in this paper. The work was performed within the scope of a MA-thesis at the State Academy of Art and Design Stuttgart. Samples of a modern new limed goat parchment and pieces of reconstituted parchment made from bovine hide powder were subjected to a combination of light ageing and dynamic ageing at moderate temperatures. All samples were analysed with the goal to observe degradation on as many structural levels as possible: colour measurement via VIS spectrometry and light-microscopic observation of fibre damage were employed to assess visible changes. Shrinkage temperature (Ts) was measured as an indicator for the amount of intact intrafibrillar bonds and the determination of the maximum moisture absorption capacity gave an impression on the parchments overall level of hygroscopy. In addition, PMF (Peptid Mass Fingerprinting) via MALDI/MS TOF was performed on extracts from unaged and light aged goat parchment. The results of the different types of analysis showed significant degradation on different structural levels of the parchment, indicating that accelerated ageing of parchment that uses a combination of light and dynamic ageing may be a viable alternative to the more commonly applied thermal ageing. [ABSTRACT FROM AUTHOR]

The allergens absorbed in immunoreactive form by the gut epithelium might induce the occurrence of allergy. The purpose of this study was to investigate the absorption and intracellular accumulation of the intact or hydrolyzed glycinin in the porcine intestinal epithelial cells (IPEC-J2). The IPEC-J2 cells were incubated by 0, 0.25, 0.5 and 1.0 mg/mL glycinin or its hydrolysate for 2, 4, 8 or 12 h. The amounts of immunoreactive glycinin were measured by enzyme-linked immunosorbent assay. The intact and hydrolyzed glycinin fragments of epithelial absorption were identified by immunoblotting and mass spectrometry (MS). We found that glycinin or its hydrolysate is expensively absorbed with the increase of dose and time. The 35 kD or 22 kD protein with glycininspecific epitopes was detected in the intracellular extracts and basolateral solutions. The results indicate that the glycinin or its hydrolysate could be absorbed; meanwhile, the 35kD or 22kD protein was correspondingly produced during absorption. [ABSTRACT FROM AUTHOR]

The interaction of cresol red (CR) with cetylpyridinium bromide (CPB), sodium dodecyl sulphate (SDS), and Triton X-100 (TX-100) was studied in aqueous solutions employing conductometric, tensiometric, and spectroscopic methods. Various micellar and interfacial parameters were calculated in absence and in presence of CR. The interactions suggest the formation of a CR-CPB adduct, an association of CR with the micelle of TX-100 while no adduct is formed between CR and SDS. Appreciably low critical micelle concentration, CMC value of TX-100 compared with those of CPB and SDS in pure water and drastic reduction of CMC of CPB (about one-twelfth of its value in pure water) than SDS and TX-100 in the presence of CR were observed. Higher negative values of Gibbs free energy of micellization, ΔGm0, for all the three surfactants indicate that micellization process is spontaneous. The values of maximum surface excess concentration, Γmax, and minimum area per molecule, Amin, suggest that in the presence of CR, the air-solution interface is closely packed and the orientation of surfactant molecules is almost perpendicular to the surface. UV-visible spectra suggest the formation of ion-pair complex between the dye CR and the monomers of CPB in the pre-micellar region, while above the CMC a breaking up of the ion-pair complex takes place and the dye is solubilized in the micelles of CPB. In the case of SDS the absorption spectra indicate weak interaction between CR and SDS molecules formation of H-bonding, short range dispersive forces, and hydrophobic interactions between CR and TX-100 molecules in the solution. [ABSTRACT FROM AUTHOR]

The emission of carbon dioxide (CO2) into the atmosphere is considered the main cause of global warming. CO2 is mostly viewed as the principal product associated with the combustion of fossil fuels. One of the emerging studies at the moment is the use polymeric ionic liquids (PILs) for capturing CO2 from flue gas streams. The objective of this paper is to provide an overview of the various PILs for CO2 capture. PILs can be used in different processes, including absorption, membrane, and adsorption. In this paper, preparation and synthesis of PILs for various processes are discussed. The paper includes elaboration on using composite, grafted, and blended PILs to achieve a powerful and effective capture mode. The effects of different parameters such as temperature and pressure on CO2 sorption are also discussed. [ABSTRACT FROM AUTHOR]

Three new manganese(II) complexes, {[Mn(PTP)]2[Mn(PTP)(H2O)]}(BTA)2·2H2O ( 1), [Mn(PTP)(ODA)]2 ( 2), and [Mn(FTP)(ODA)]2·H2O ( 3), were synthesized by the reactions of manganese acetate and polycarboxylic acid in the presence of N-heterocyclic ligands (where PTP=4′-phenyl-2,2′:6′,2″-terpyridine, H3BTA=benzene-1,3,5-tricarboxylic acid, H2ODA=4,4′-oxydibenzoic acid, FTP=4′-(furan-2-yl)-2,2′:6′,2″-terpyridine). In complex 1, each BTA ligand serves as a μ3-bridge to link three Mn(II) centers, whereas each Mn(II) center is coordinated by two BTA ligands. This connection mode results in a grid sheet. Complexes 2 and 3 have very similar molecular structures with Mn(II) centers connected by ODA ligands to result in ring-like arrays. We investigated the third-order nonlinear optical (NLO) properties of the three complexes by single beam Z-scan techniques. Complexes 1- 3 exhibit strong third-order NLO reverse saturable absorption with NLO absorptive indices β=1.32×10−6, 3.01×10−6, and 9.42×10−6 m W−1, respectively. In addition, complex 1 shows all excellent self-focusing effect with an NLO refractive index of γ=1.25×10−12 m2 W−1. The third-order NLO susceptibility χ(3) of the three complexes were calculated as 47.55×10−8, 4.85×10−8, and 15.16×10−8 esu, respectively. [ABSTRACT FROM AUTHOR]

This paper investigates photoacoustic tomography with two spatially varying acoustic parameters, the compressibility and the density. We consider the reconstruction of the absorption density parameter (imaging parameter of Photoacoustics) with complete and partial measurement data.We investigate and analyze three different numerical methods for solving the imaging problem and compare the results. [ABSTRACT FROM AUTHOR]

A superhydrophobic surface on wood can prevent water adhesion and absorption. However, the practical applications of such a non-wetting surface are hindered by the fragility of the microscopic roughness features that are essential for superhydrophobicity. In this study, semitransparent, mechanically durable superhydrophobic coating was successfully deposited on varnished wood via a simple dip-coating method based on polydimethysiloxane (PDMS)/silica (SiO2) nanocomposites. The surface microstructure and roughness of the hybrid coatings on wood are governed by the mass ratio of SiO2 to PDMS. When the nano-SiO2 particle content reaches a critical level, dual-scale features with micro-scale roughness superimposed with a nanostructure can be formed in the surface coatings, resulting in excellent water-repellency with a contact angle above 150° and a sliding angle below 10°. The coated wood surface maintained essentially the original colour and aesthetic appearance despite slightly declined optical transparency of the hybrid coating caused by aggregation of silica nanoparticles. Sandpaper abrasion tests revealed that the superhydrophobic PDMS/SiO2 hybrid coating on wood retained its microstructure and superhydrophobicity after being repeatedly abraded. [ABSTRACT FROM AUTHOR]

C17H14BrNO2, monoclinic, C2/c (no. 15), a = 31.437(3) Å, b = 5.5224(5) Å, c = 16.6545(16) Å, β = 94.703(4)°, V = 2881.6(5) Å3, Z = 8, Rgt(F) = 0.0251, wRref(F2) = 0.067, T = 173(2) K. [ABSTRACT FROM AUTHOR]

In this study, Ca K-edge X-ray absorption spectroscopy (XAS) has been employed to study the Ca structural role in a set of silicate glasses. For the first time the accurate analysis of the Ca pre-edge peak has been performed, providing information about the different Ca local environments, and on its structural role. This approach was tested on Ca-aluminosilicate glasses (CAS system) with constant SiO2 content (50 and 76 mol%), ranging from percalcic to peraluminous domains. In alkali-earth aluminosilicate glasses Al and Si are network formers in a large range of compositions, whereas calcium should act either as network modifier and charge compensator. The results obtained show a different Ca behavior as a function of Al content, which in turn is related to the Al local environment. For example, we observe changes in the pre-edge peak centroid energies depending on the changes in the role of Ca as a network modifier (Al = 0 mol%) to charge compensator (aluminosilicate join) to a more complex role in the peraluminous domain, depending on the fraction of [4],[5],[6]Al. This approach was further applied to study Fe-bearing glasses and, a diopside (CaMg2Si2O6) composition at different temperatures. It was possible to correlate the variations occurring in the Ca pre-edge peak centroid positions with both redox state and crystal nucleation mechanism. [ABSTRACT FROM AUTHOR]

Pre-edge features in the K absorption edge of X-ray absorption spectra are commonly used to predict Fe3+ valence state in silicate glasses. However, this study shows that using the entire spectral region from the pre-edge into the extended X-ray absorption fine-structure region provides more accurate results when combined with multivariate analysis techniques. The least absolute shrinkage and selection operator (lasso) regression technique yields %Fe3+ values that are accurate to ±3.6% absolute when the full spectral region is employed. This method can be used across a broad range of glass compositions, is easily automated, and is demonstrated to yield accurate results from different synchrotrons. It will enable future studies involving X-ray mapping of redox gradients on standard thin sections at 1 x 1 µm pixel sizes. [ABSTRACT FROM AUTHOR]

The knowledge of vapour-liquid equilibrium (VLE) and thermodynamic properties plays a pivotal role in the process development of absorption systems for acid gas capture in precombustion and postcombustion streams. A large number of thermodynamic modelling approaches for acid gas absorption in aqueous alkanolamine solutions are published in the literature. However, the reviews of these modelling techniques are limited and scattered. Moreover, poor guidelines exist for the selection of an appropriate modelling approach for the VLE prediction of the aforementioned system. Therefore, the current study presents a concise classification and review of classical thermodynamic models for acid gas absorption in aqueous alkanolamine solutions since their inception. The article systematically details the chronological development and highlights the major capabilities and limitations of classical thermodynamic approaches, namely, semiempirical models, activity coefficient models, and equation of state (and equation of state/excess Gibbs energy) models. A graphical comparison of VLE prediction by each classical approach is presented to form a general guideline in the selection of a suitable approach for process development studies. The review precisely discusses the issues, challenges, and future prospects of each classical thermodynamic approach in the context of application, complexity, and development. [ABSTRACT FROM AUTHOR]

The development of high performance uncooled infrared (IR) detection and imaging systems will greatly expand the application of IR technology in broad areas such as transportation, environmental monitoring, and medical care. Inspired by the superior IR detection capability of beetle Melanophila acuminata, we explored the potential use of hydrogel nanoparticles (NPs) in uncooled IR detection system. In the system, the absorption of the incoming IR radiation by the temperature-sensitive hydrogel NPs, together with water, induces the volume change of the hydrogel NPs, similar to the volume change of the biofluid inside the sensillae receptors in M. acuminata caused by the IR radiation. This volume change results in the change of optical readout (transmittance in this study) in visible range and provides the sensitive detection of the IR radiation. In this work, poly(N-isopropylacrylamide-co-acrylic acid) (poly(NIPAM- co-AAc)) copolymer NPs with different sizes were synthesized and their IR sensing performances were studied in detail. The correlation between the NP size and concentration and the IR sensing property was also discussed in the paper. This work helps enhance the understanding of the response of hydrogel NPs under IR radiation, and offers a potential material system for uncooled IR detection that is inspired by M. acuminata. The direct use of transmittance of the NP solution as the readout for IR detection also provides a simple and sensitive IR detection approach for low cost and portable industrial applications. [ABSTRACT FROM AUTHOR]

The development of high performance uncooled infrared (IR) detection and imaging systems will greatly expand the application of IR technology in broad areas such as transportation, environmental monitoring, and medical care. Inspired by the superior IR detection capability of beetle Melanophila acuminata, we explored the potential use of hydrogel nanoparticles (NPs) in uncooled IR detection system. In the system, the absorption of the incoming IR radiation by the temperature-sensitive hydrogel NPs, together with water, induces the volume change of the hydrogel NPs, similar to the volume change of the biofluid inside the sensillae receptors in M. acuminata caused by the IR radiation. This volume change results in the change of optical readout (transmittance in this study) in visible range and provides the sensitive detection of the IR radiation. In this work, poly(N-isopropylacrylamide-co-acrylic acid) (poly(NIPAM-co-AAc)) copolymer NPs with different sizes were synthesized and their IR sensing performances were studied in detail. The correlation between the NP size and concentration and the IR sensing property was also discussed in the paper. This work helps enhance the understanding of the response of hydrogel NPs under IR radiation, and offers a potential material system for uncooled IR detection that is inspired by M. acuminata. The direct use of transmittance of the NP solution as the readout for IR detection also provides a simple and sensitive IR detection approach for low cost and portable industrial applications. [ABSTRACT FROM AUTHOR]

Concern has increased about climate change caused by carbon dioxide (CO2) emissions through human activities in recent years. The Intergovernmental Panel on Climate Change predicts a 1.9°C rise in temperature by the year 2100, and this means a reduction in CO2 is vital for human beings and all other life on earth. Therefore, there is an urgent need for the development of CO2 separation processes to mitigate this potential problem. Post-combustion power plants can employ various types of separation technology. Among them, chemical absorption using aqueous amine is more developed and more reliable. The conventional solvents used in the chemical absorption process together with the use of absorbents, ionic liquid, alkanolamines and their blended aqueous solutions are reviewed in this work. Different ionic liquid-based solvents for CO2 absorption and the most effective parameters on mass transfer phenomena between CO2 and solvent are reviewed. The major concerns for this technology, including the physiochemical properties of ionic liquid-based solvents, Henry's constant and mass transfer coefficient and their correlations, and various factors for effective CO2 absorption, are addressed. [ABSTRACT FROM AUTHOR]

Fossil fuels are the major energy source used in the world and will continue to dominate in the future. For the coal-dependent countries, the key to the emission reduction of CO2 will be the capture of CO2 in coal-fired power plants. Currently available CO2 sorbents are reviewed in this paper. Based on the principles of various separation technologies, absorption and adsorption are discussed accordingly. In terms of the application temperature, absorption materials are categorized into high-temperature absorbent and low-temperature absorbent and their latest progress are included. For the adsorption, different materials such as activated carbon, zeolite and MOFs and etc. are discussed thoroughly. At the end, the future trend of CO2 separation is proposed. It is suggested that since any single method cannot meet the requirements of coal-fired power plants, feasible approach for CO2 separation will be to combine the advantages of all the available methods, for example, adsorbents impregnated with amines, porous polymer impregnated with organic solvents and new structured adsorbents such as ionic liquids and metal organic frames. [ABSTRACT FROM AUTHOR]

The water absorption of soybeans ( Glycine max (L.) Merr.) during soaking is directly related to their textural characteristics and grinding properties during processing. In this study, we determined the effects of vacuum soaking on the absorption of water and salt solutions by soybeans. We also analyzed the textural characteristics and grinding properties of soybeans soaked under atmospheric and vacuum pressures (0.02-0.08 MPa) for 8 and 16 h. The results showed that vacuum soaking promoted the absorption of water and NaHCO3 solution. Vacuum soaking also decreased the hardness of soybeans. Soaking under vacuum significantly shortened the soaking time required for soybeans. Additionally, the protein content was higher in soymilk made from vacuum-soaked soybeans than in soymilk made from soybeans soaked under atmospheric pressure. [ABSTRACT FROM AUTHOR]

We study properties of the central sequence algebra of a C*-algebra A, and we present an alternative approach to a recent result of Matui and Sato. They prove that every unital separable simple nuclear C*-algebra, whose trace simplex is finite-dimensional, tensorially absorbs the Jiang-Su algebra if and only if it has the strict comparison property. We extend their result to the case where the extreme boundary of the trace simplex is closed and of finite topological dimension. We are also able to relax the assumption on the C*-algebra of having the strict comparison property to a weaker property that we call local weak comparison. Namely, we prove that a unital separable simple nuclear C*-algebra, whose trace simplex has finite-dimensional closed extreme boundary, tensorially absorbs the Jiang-Su algebra if and only if it has the local weak comparison property. We can also eliminate the nuclearity assumption if instead we assume the (SI) property of Matui and Sato, and, moreover, that each II 1-factor representation of the C*-algebra is a McDuff factor. [ABSTRACT FROM AUTHOR]

Fossil fuels are the major contributors to the emission of anthropogenic carbon dioxide (CO2) to the atmosphere, rendering global warming a challenging issue to the researchers and industries. Although natural gas has been recommended as a clean fuel compared to other fossil fuels, geological sources of natural gas are not free of impurities. Economical commercialization of natural gas with high sour gas contents as well as facilitating the geosequestration of sour gases for enhanced oil recovery (EOR) need several environmentally sound and cost-effective gas separation methods. Moreover, stringent restrictions should be drawn to mitigate the unfettered greenhouse gas emissions to the atmosphere. In the present study, existing low-temperature conventional CO2 capture methods, namely, cryogenic distillation process along with emerging nonconventional and hybrid methods, have been demonstrated. Also, the limitations and operational conditions during the application of these processes have been mentioned. The future prospects of the emerging technologies have been compared with conventional methods. Hybrid cryogenic distillation networks for multiproduct industrial production of different hydrocarbons and CO2 products at higher pressures of 40 bar and above showed promising potentials. A concise classification and summary of innovative emerging technologies along with conventional methods has been presented in this paper for possible future commercial exploitation. [ABSTRACT FROM AUTHOR]

An understanding of the mineralogy and petrogenesis of rare earth element deposits has significant implications for their economic viability. Lanthanide-bearing compounds are known to produce sharp absorption features in the visible to short-wave infrared region (VIS-SWIR), however, a significant knowledge gap exists between the fields of hyperspectral reflectance spectroscopy and rare earth element mineralogy. Reflectance spectra were collected from four bastnäsite samples, two parisite samples, and one synchysite sample from the visible into the short-wave infrared. These REE fluorocarbonate mineral samples were characterized via scanning electron microscopy and electron probe microanalysis. Sharp absorptions of REE-bearing minerals are mostly the result of 4f-4f intraconfigurational electron transitions and for the light REE-enriched fluorocarbonates, the bulk of the features can be ascribed to Nd3+, Pr3+, Sm3+, and Eu3+. The lanthanide-related spectral responses of the REE fluorocarbonates are consistent across the group, supporting the notion that the REE cation site is very similar in each of these minerals. Carbonate-related spectral responses differed between these minerals, supporting the notion that the crystallographic sites for the carbonate radical differ between bastnäsite, synchysite, and parisite. Exploitable spectral differences include a distinct absorption band at 2243 nm that separates bastnäsite from synchysite and parisite. Similarly, for bastnäsite a dominantly Pr3+-related absorption band located is at 1968 nm, while in synchysite and parisite it occurs at 1961 nm. [ABSTRACT FROM AUTHOR]

The objective of this study was to determine normal impedance on the surface as well as sound absorption coefficients for several wood species from Europe and from the tropical zone. The mathematical models of Miki, Attenborough, and Allard - dealing with acoustic properties of porous materials - have also been compared. The air flow resistivity exhibits a distinct link between fiber dimensions and wood porosity. The highest sound absorption coefficient was found for oak, ash, sapeli, and pine woods at 2 kHz frequency. The Attenborough model provides results closest to laboratory measurements, although it still requires significant improvements. The Miki and Allard models have some drawbacks and should be applied with reservation for the determination of wood acoustic properties. [ABSTRACT FROM AUTHOR]

The ability of successive ionic layer deposition (SILD) technology to synthesize gold clusters on the surface of tin(IV) oxide and indium(III) oxide films is discussed. It was shown that during the process, concentration of active sites that are capable of absorbing gold ions, and the size of the gold particles thus formed, may be controlled by both concentration of the solutions used and the number of SILD cycles. Thus, SILD methodology, employing separate and multiple stages of adsorption and reduction of adsorbed species, has considerable potential for customizing the properties of the deposited metal nanoparticles. In particular, it is shown that during the deposition of gold nanoparticles on the surface of tin(IV) oxide and indium(III) oxide films by SILD methodology, conditions can be realized under which the size of gold nanoclusters may be controllably varied between 1-3 nm and 50 nm. A model is proposed for the formation of gold clusters during the SILD process. [ABSTRACT FROM AUTHOR]

In this study, toluene-ethanol mixtures were investigated as chemical modifying agents for pine cone powder (PCP) and the optimum modification ratio determined by measuring the improvement in surface properties of the PCP such as Brunauer-Emmett-Teller (BET) surface area, bulk density, and surface negative charge. The modified adsorbents were then applied for the removal of cesium ions from aqueous solution. The result revealed that the chemically modified PCP had better surface properties than the raw BET surface area, and X-ray diffraction (XRD) spectra revealed that the surface area improved and cellulose crystallinity reduced. Cesium adsorption by the chemically modified PCP was much higher than for the raw PCP. Desorption studies were also performed to evaluate the mechanism of adsorption. [ABSTRACT FROM AUTHOR]

Past reports indicate that some nanoparticles (NPs) affect seed germination; however, the biotransformation of metal NPs is still not well understood. This study investigated the toxicity on seed germination/root elongation and the uptake of ZnO NPs and Zn2+ in alfalfa (Medicago sativa), cucumber (Cucumis sativus), and tomato (Solanum lycopersicum) seedlings. Seeds were treated with ZnO NPs at 0-1600 mg L-1 as well as 0-250 mg L-1 Zn2+ for comparison purposes. Results showed that at 1600 mg L-1 ZnO NPs, germination in cucumber increased by 10 %, and alfalfa and tomato germination were reduced by 40 and 20 %, respectively. At 250 mg Zn2+ L-1, only tomato germination was reduced with respect to controls. The highest Zn content was of 4700 and 3500 mg kg-1 dry weight (DW), for alfalfa seedlings germinated in 1600 mg L-1 ZnO NPs and 250 mg L-1 Zn2+, respectively. Bulk X-ray absorption spectroscopy (XAS) results indicated that ZnO NPs were probably biotransformed by plants. The edge energy positions of NP-treated samples were at the same position as Zn(NO3)2, which indicated that Zn in all plant species was as Zn(II). [ABSTRACT FROM AUTHOR]

The influence of stresses on the crust phase of Colpomenia bullosa, originally thought to be Ralfsia verrucosa, inhabiting rockpools above the lowest high water on Kainga Reef, SE New South Wales, was investigated. The mean densities of grazing gastropods Nerita atramentosa and Austrocochlea porcata were 107 and 59 animals m-2, respectively, with no seasonal variation. Some pools were more attractive to Austrocochlea than others. Herbivore impact on C. bullosa crust was assessed by collecting and examining feces and counting the number of crust filaments. Seasonal variations in grazing and in crust cover were not related in a way that would suggest a causal relationship. The calculated annual consumption was 7% of the crust. Grazing probably kept the crust clean of epiphytes. When local conditions isolated the pools from the sea for days, some crusts survived a known salinity of 127 psu and an estimated 175 psu. The crust of C. bullosa on pool sides survived up to 58 h of emersion, but complete drying on pool bottoms was lethal within 14 h presumably as a result of saturating salinity preceding complete drying. UVB-absorbing substances, assumed to be phlorotannins, were released by the crust during pool drying. It is concluded that high temperatures were the likely cause of both the slow growth rate and the high mortality of C. bullosa crust on Kainga Reef in summer. [ABSTRACT FROM AUTHOR]

Procedures for the determination of photoluminescence quantum yields with optical methods are addressed, and challenges associated with these measurements are discussed. Special emphasis is dedicated to relative measurements of fluorescent (i.e., short excitedstate lifetime), transparent, dilute dye solutions in conventional cuvettes in a 0°/90° measurement geometry. Recommendations on the selection of suitable quantum yield standards are presented, and requirements for the documentation of photoluminescence quantum yields are derived. [ABSTRACT FROM AUTHOR]

Owing to the high measuring speed and requirement of less or even no sample preparation, spectroscopic technologies have been increasingly applied in areas of food technology, agriculture, and pharmaceutics where heterogeneous samples are more frequently encountered than homogeneous ones. For heterogeneous samples, the potential uncontrolled variations in optical path length due to the physical variations such as particle size and distribution, shape and sample packing may cause dominant multiplicative light scattering perturbations which will mask the spectral variations related to the content differences of chemical compounds in samples and hence deteriorate the accuracy and reliability of quantitative spectroscopic analysis. Consequently, with a view to improve the accuracy and reliability of spectroscopic analysis for heterogeneous samples, a number of chemometric techniques have been developed to correct for the effects of multiplicative light scattering. This paper reviews currently available correction techniques for absorption spectroscopy with emphasis on their theories, limitations, and suitability for practical applications. [ABSTRACT FROM AUTHOR]

Ultra-lightweight foam core particleboards have been produced in a novel one-step process with resinated wood particles for the faces and expandable polystyrene (EPS) as core layer material. The mechanical and physical properties of panels were investigated in terms of the different foam core densities and press parameters (temperature, pressing and foaming time). The bending strength properties of the panels were not significantly changed with increasing foam core density from 80 to 120 kg m-3. Panels produced at a press temperature of 130°C (1-EPS) have an improved core-face interface and also a denser surface layer, which positively influences the internal bond and thickness swelling. The panels produced at a press temperature of 160°C (2-EPS) have smaller and more foam cells and an improved fusion of foam beads and properties, which have a positive influence on the edge screw withdrawal resistance and water absorption. [ABSTRACT FROM AUTHOR]

We performed hydration experiments of pure and Nb-, Cr-, and V-doped synthetic dry (H2O < 3 ppm) single rutile crystals. They were equilibrated with pure H2O in hydrothermal experiments at constant conditions of 600 °C, 400 MPa, and fO2 near the Ni-NiO buffer, run time between ~25 min and 14 days. Slabs cut parallel to (110) of the reacted single crystals (1 to 2 mm³) were analyzed for H+ by FTIR. Hydration occurs almost spontaneously and the H2O-equivalent is uniformly distributed in the samples, but depends extremely on trace element contents. In pure rutile, the average H2O-content is 314 ± 50 ppm, the saturation level at these conditions. Rutile doped with 500 ppm Nb has a lower average H2O content of ~235 ppm, rutile with 2000 ppm Cr has ~900 ppm H2O, and rutile with 2000 ppm V does not incorporate H2O. During stepwise heating at atmospheric pressure of a reacted Nb-doped rutile, H+ is quickly released between 450 and 550 °C. UV-VIS spectra of unreacted colorless and reacted deep blue pure rutile show the rutile-characteristic sharp absorption edge in the UV spectra. The reacted rutile has a broad absorption band at 6500 cm-1 wavenumber attributed to intervalence charge transfer transition Ti3++Ti4+ → Ti4++Ti3+. The reduction of Ti4+ to Ti3+ is charge balanced by the incorporation of H+. The Nb-doped rutile changed its color from light greenish-blue (untreated) to deep blue. In the untreated Nb rutile, the UV-VIS absorption band at 6500 cm-1 indicates that Nb5+ is charge balanced by Ti3+. In the reacted Nb-rutile the absorption band is more intense, but compared with the pure rutile, H+ incorporation is lower by the equivalent of Ti3+ reduced in the untreated rutile. Reacted Cr-rutile almost retains its brownish-orange color, but the spectrum shows a prominent Ti3+/Ti4+ IVCT band at ~6400 cm-1 with moderate intensity considering the high-H2O contents of ~900 ppm. The high-H+ contents are best explained by the reduction of Cr4+ to Cr2+. The UV-VIS spectra of the dark-blue to opaque V-doped rutile show a very strong absorption toward low energies, which is likely caused by reduction of Ti4+ to Ti3+ for charge balance of V5+. This forms a deep narrow window of transmittance in the range 25 000--20 000 cm-1, which causes the dark-blue color. To explore the possible use of H-in-rutile as a geohygrometer, geothermobarometer, and oxybarometer, we measured the H+ content in a natural rutile crystal from a retrograded eclogite with a zoned trace element (Fe, Nb, and Zr) content. The crystal reveals a slight correlation between the variable H2O (~200 to 900 ppm) and its trace element concentrations. The observations indicate that the preservation of H+ contents in this natural rutile is a complicated interplay of diffusive reequlibration of fast H+, slower Fe and very slow other trace elements. An interpretation of the H2O contents of the natural crystal in terms of fO2 or aH2O is not possible. [ABSTRACT FROM AUTHOR]

Objectives: Carrot residue as low cost, non-conventional adsorbent was used for biosorptive removal of lead and cadmium from the aqueous solution. Methods: A batch adsorption method was experimented for biosorptive removal of lead and cadmium ions from the aqueous solution. Findings: Experimental data fitted well to both Langmuir and Freundlich isotherm models. The calculated qmax for lead and cadmium was 0.522 mg/g and 0.421 mg/g respectively. Thermodynamic parameters like ΔG, ΔH and ΔS showed spontaneity endothermic nature of adsorption for cadmium ion and exothermic nature for the lead ions. Nearly 93% removal of lead and 92% removal of cadmium were observed in about 35 minutes at pH @ 3 and 5 respectively, under the batch test conditions. Conclusion: Carrot residue was investigated as low cost non-conventional adsorbent for the sorption of cadmium and lead ions from the contaminated water under various experimental conditions like pH, dosage amount and contact time. [ABSTRACT FROM AUTHOR]

Aims: The purification of an acid DNase related DNase II family from lysosomes of human small intestine (jejunum). Materials and Methods: Two different methods: a column chromatography series, including phosphocellulose, CM-cellulose and Sephadex G-200 and a novel procedure that use immunoabsorbent technique were used in the purification. Results: The purified DNase is an endonuclease that consisted of one polypeptide chain (monomer) with a molecular mass of 28-32kDa with an optimal pH and temperature of 6.0 and 30°C, respectively. The enzyme prefers native DNA on denatured DNA Discussion: The catalytic properties of the purified enzyme are essentially the same as those of DNase II family such as independency of divalent ions which inhibited its activity at 10mM. The enzyme acts on dsDNA and ssDNA and generates 3'-phosphate and 5'-OH termini which was a characteristic of DNase II. The functions of the intestinal purified DNase from lysosomes were unclear, but lysosomes contained a set of enzymes required for degradation of food, and the enzyme may be necessary for degradation of nucleic acids within food, but small amounts of the enzyme were found in the nuclei and cytoplasm were detected. Several researchers suggested that DNase II family may be active in apoptosis and played a role as a barrier to transfection. The purified was designated SIDNase. [ABSTRACT FROM AUTHOR]