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Oxygen K-edge X-ray absorption spectroscopy is used routinely to study a range of solid materials. However, liquid samples are studied less frequently at the oxygen K-edge due to the combined challenges of high-vacuum conditions and oxygen contamination of window materials. A modular sample holder design with a twist-seal sample containment system that provides a simple method to encapsulate liquid samples under high-vacuum conditions is presented. This work shows that pure silicon nitride windows have lower oxygen contamination than both diamond- and silicon-rich nitride windows, that the levels of oxygen contamination are related to the age of the windows, and provides a protocol for minimizing the background oxygen contamination. Acid-washed 100 nm-thick silicon nitride windows were found to give good quality oxygen K-edge data on dilute liquid samples.

Until recently, sulfur was known as a "spectroscopically silent" element because of a paucity of convenient spectroscopic probes suitable for in situ chemical speciation. In recent years the technique of sulfur K-edge X-ray absorption spectroscopy (XAS) has been used extensively in sulfur speciation in a variety of different fields. With an initial focus on reduced forms of organic sulfur, we have explored a complementary X-ray based spectroscopy - sulfur Kβ X-ray emission spectroscopy (XES) - as a potential analytical tool for sulfur speciation in complex samples. We compare and contrast the sensitivity of sulfur Kβ XES with that of sulfur K-edge XAS, and find differing sensitivities for the two techniques. In some cases an approach involving both sulfur K-edge XAS and sulfur Kβ XES may be a powerful combination for deducing sulfur speciation in samples containing complex mixtures.

Considering the need for housing in recent decades as one of the most basic human needs, and in line with the country's major policies and the importance of home in the religion of Islam, Thus, the emphasis on the principles of housing architecture design, according to the Islamic epistemic system, seems to be an important and indispensable factor in achieving the desired quality of housing. Thus, the present study seeks to answer the question of how well the original Islamic and Qur'anic concepts have been able to be expressed in contemporary physical and functional dimensions in the context of contemporary housing patterns. While explaining the components of Islamic value in the field of housing architecture, in this regard, this research will be done through a combination of two main steps. In the first step, by descriptive-analytical research method and by gathering information in the form of library and documentary studies with the help of first-rate religious sources (Quran Majid), he will extract religious concepts and then specialize the concepts according to the theoretical foundations of research. In the second step, we will evaluate and prioritize the indicators presented in the analytical model from the experts' point of view and evaluate the same indicators in the case samples by fuzzy hierarchy (AHP) technique. The results show that architectural patterns derived from Qur'anic concepts and teachings can be classified into two domains of functional and physical architecture components in Islamic housing. According to the experts, the sub-components of "location" and "geometry" with the weights of 0.217 and 0.275 have the highest importance factor in the functional and physical components, respectively.

Organic sulfoxides, a group of compounds containing the sulfinyl S[double bond, length as m-dash]O group, are widespread in nature, important in health and disease, and used in a variety of applications in the pharmaceutical industry. We have examined the sulfur K-edge X-ray absorption near-edge spectra of a range of different sulfoxides and find that their spectra are remarkably similar. Spectra show an intense absorption peak that is comprised of two transitions; a S 1s → (S-O)σ* and a S 1s → [(S-O)π* + (S-C)σ*] transition. In most cases these are sufficiently close in energy that they are not properly resolved; however for dimethylsulfoxide the separation between these transitions increases in aqueous solution due to hydrogen bonding to the sulfinyl oxygen. We also examined tetrahydrothiophene sulfoxide using both the sulfur and oxygen K-edge. This compound has a mild degree of ring strain at the sulfur atom, which changes the energies of the two transitions so that the S 1s → [(S-O)π* + (S-C)σ*] is below the S 1s → (S-O)σ*. A comparison of the oxygen K-edge X-ray absorption near-edge spectra of tetrahydrothiophene sulfoxide with that of an unhindered sulfoxide shows little change, indicating that the electronic environment of oxygen is very similar.

Aryl and mixed aryl-alkyl organic sulfides are important species in a variety of fields, including the drug and food industries. They also are present in fossil fuels, where they contribute to the range of sulfur compounds that must be removed by the fuel industry. We have used sulfur K-edge X-ray absorption spectroscopy, in combination with density functional theory calculations, to study the aryl sulfide diphenyl sulfide and two different aryl-alkyl sulfides. The sulfur K near-edge X-ray absorption spectra are strongly affected by the coordination of the phenyl ring and are distinct from spectra of the alkyl sulfides. For diphenyl sulfide the spectra are predicted to be sensitive to rotation about the S-C bonds, with experimental spectra corresponding to a sum of thermally accessible conformations. We also have investigated the vapor-phase spectrum of diphenyl sulfide, which is found to be very similar to that of toluene solutions of the compound.

An impedance-based Point Defect Model (PDM) was developed for the potentiostatic, anodic formation of gold oxide at potentials of 1.40–1.70 V vs SHE in H2SO4 (0.1 M and 0.5 M). Film thickness and refractive indices were determined at each oxide formation potential using spectroscopic ellipsometry. The thickness of the oxide increases linearly with increasing potential. Mott-Schottky analysis shows that the oxide exhibits both n-type and p-type character and the dominant defect density is calculated to be in the order of 1021−1022 (1 cm−3). The PDM was optimized upon experimental EIS data to extract values for model parameters and accounts well for the experimental observations in both the steady-state time and frequency domains.

Inhibition of Type 304 L SS corrosion in 0.5 M HCl by New Fuchsin is reported using potentiodynamic polarization, electrochemical impedance spectroscopy, scanning electron microscopy (SEM), and energy dispersive X-ray (EDX) techniques. The study was complemented by DFT calculations and Monte Carlo simulation (MCS), and the data were interpreted in terms of the Point Defect Model (PDM) and the Anion-Catalyzed Active Dissolution Model (ACADM). Both account for the experimental data. DFT and MCS simulation show that aromatic rings and -NH2 groups interact with the Cr2O3 surface and the inhibitor adopts a lateral configuration on the surface.

Polydopamine (PDA) coating on a copper surface was successfully prepared using a two-step process. In the first stage, in order to improve the adhesion of PDA on the copper surface, a self-assembled monolayer of L -cysteine was deposited on a bare copper. Thereafter, the PDA coating was fabricated through the chemical adsorption and auto-polymerization of the dopamine hydrochloride on the L -cysteine-coated copper surface. The inhibitory behavior of L -cysteine and PDA films has been investigated in aqueous 3.5% NaCl solution using potentiodynamic polarization and electrochemical impedance spectroscopy. It is demonstrated that the L -cysteine/PDA coating provides significant protection against copper corrosion.

article i nfo Inthisstudy,cobaltdisulfide (CoS2)nanoparticleshavebeensuccessfullysynthesizedthrougha simpleandfacile solvothermal method. The experiments were carried out based on the thermodynamic calculations using FactSage software. The black nano-sized CoS2 powder has been produced in an autoclave reactor. The reaction parameters, such as the ratio of primary salts, effect of solvents, temperature and surfactant were optimized to obtain fine and uniform nanoparticles. The band gap energy of the samples was measured with butler relations. The results proved the production of highly pure CoS2 nanoparticles with a semi-spherical morphology.

In this paper, we describe the use of Volt-Equivalent Diagrams (VEDs) to display the electrochemical thermodynamics of one of the most complicated chemical systems in nature; the S–H 2 O system, as it relates to the use of copper for the isolation of high level nuclear waste (HLNW) in granitic repositories in Sweden. The complexity stems from this element having oxidation states that vary from −2 to +8 including a multitude of fractional oxidation states. The volt equivalent describes the reactivity of a species and foretells the various chemical transformations that may occur between different sulfur-containing species in the system.

The corrosion and cell viability behaviors of nanostructured, nickel-free stainless steel implants were studied and compared with AISI 316L. The electrochemical studies were conducted by potentiodynamic polarization and electrochemical impedance spectroscopic measurements in a simulated body fluid. Cytocompatibility was also evaluated by the adhesion behavior of adult human stem cells on the surface of the samples. According to the results, the electrochemical behavior is affected by a compromise among the specimen's structural characteristics, comprising composition, density, and grain size. The cell viability is interpreted by considering the results of the electrochemical impedance spectroscopic experiments.

One of the centers that have high sensitivity for design is psychotherapy center because of special physical, mental and sentimental conditions of their patient. Design and architecture of psychotherapy centers and caring mental patients are new subjects in our country; and there was no attempt to study and design of this center by interior specialist. To start design of every usage, recognition of habitants of that place is necessary. Recognition and understanding of different needs of Schizophrenic patients and attempt to meet their needs and respect to priority of these needs in designing and improving their special spaces can be effective in improvement of its quality. Schizophrenia is a chronic and debilitating illness which is associated with impaired social and occupational skills and it affects approximately one percent of the population. Since these patients are considered one of the most disadvantaged sectors of society, and their main requirement is to help them to return home and social environment, it should be possible to step in improving treatment by identifying and using elements of environmental quality and to introduce the environment of a hospital as a healing environment not as an environment for permanent or long-term accommodation for patients, Because the main purpose of admission of a mental schizophrenic patients is maintenance of security of patients and others and above all is his stable treatment. But psychotherapy centers in Iran cannot fully respond to the needs of these patients. And most buildings in the old psychiatric institutions are without proper space and occupational therapy sectors are not efficient and effective. The subject of this paper is the eclectic and interdisciplinary, means architecture and psychology. Purposes of that are obtaining a codified agreement, design standards and present an architectural pattern for treatment and positive influences on mental disorders of schizophrenic patients and his return to a normal life.

Passivity breakdown and pitting on carbon steel, the material for the overpack holding the waste canister inside high-level nuclear waste supercontainer in Belgium, has been studied in simulated concrete pore solution (SCPS) with a pH of 13.5 and the data are interpreted in terms of the Point Defect Model (PDM). The near normal distribution in the critical breakdown potential (V c) measured in deaerated SCPS with different chloride concentrations is in satisfactory agreement with the quantitative prediction of the PDM. The critical areal concentration of condensed cation vacancies at the metal/film interface that leads to passivity breakdown, as predicted by the PDM from the experimental dependence of the V c on the square root of the voltage sweep rate, ξ 16 cm−2, is in excellent agreement with that calculated from the unit cell dimensions of the substrate Fe (ξ ≈ 1.53 × 1016 cm−2) and the barrier layer oxide (Fe2O3) (ξ ≈ 6.89 × 1015 cm−2) for vacancy condensation upon the metal lattice or upon the cation sublattice of the film, respectively. This observation provides convincing evidence for the validity of the PDM for modeling passivity breakdown.

Passivity breakdown on carbon steel, which is the reference candidate material for fabricating high-level nuclear waste containers in Belgium, has been studied and the data are interpreted in terms of the point defect model (PDM). The near normal distribution in breakdown potential, measured in deaerated simulated concrete pore water solution (pH 12.5) at different chloride concentrations and temperatures are in satisfactory agreement with prediction of the PDM. An increase in temperature from 25°C to 85°C results in a decrease in localized corrosion resistance according to a linear relationship between the critical breakdown voltage, Eb , and log(chloride activity) for all chloride concentrations. The linear dependence of the passivity breakdown potential on the square root of potential scan rate (ν1/2), as predicted by the PDM, yields an estimate of the critical areal concentration of condensed cation vacancies at the metal/film interface (ξ14cm-2 at 85oC and 14cm-2 at 55oC ) that leads to the passivity breakdown. The experimental distributions in the breakdown potential for carbon steel at 55oC and 85oC are in satisfactory agreement with the relevant calculated distributions. Acknowledgment: The authors gratefully acknowledge the support of this work by ONDRAF-NIRAS of Belgium.

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