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Galfenol (Fe100-xGax) is a relatively new, highly magnetostrictive active material with strains of about 330 ppm as a slow cooled single crystal and about 280 ppm as a highly textured polycrystal at x=∼18.4. Four main advantages over other materials are (1) Galfenol's structural strength; (2) the ability of a single composition to operate over the temperature range of -269-+150 °C (for stress annealed rods, higher for unannealed rods); (3) the ability of stress annealed Galfenol to provide full performance under stresses ranging from at least -160 to +30 MPa (compressive stresses are negative); and (4) the ability to use standard metal working techniques. The magnetostriction and magnetization of two stress annealed, highly textured Fe81.6Ga18.4 rods were measured at temperatures between -50 and +100 °C and tensile stresses of approximately +1, +10, +20, +30, and +40 MPa. Measurements were taken inside an environmental chamber using a spring to supply the stress. A stress change of about 2 MPa between -50 and +100 °C was typical. The saturation magnetostriction is nearly independent of stress up to 20 MPa, drops only slightly at 30 MPa, and falls off rapidly at 40 MPa. At a given stress, the saturation magnetostriction decreases roughly linearly at ∼0.3×10-6 / °C. [ABSTRACT FROM AUTHOR]

Magnetic properties, the magnetocaloric effect (MCE) and refrigerant capacity (RC) were investigated in Eu8Sr8-xGa16Ge30 (x=0,4) type-I clathrates. The substitution of Sr for Eu decreases the Curie temperature (TC) and saturation magnetization (MS) from 35 K and 65 emu/g for the x =0 composition to 15 K and 35 emu/g for the x=4 composition. This is attributed to the increase in the Eu-Eu distance with Sr substitution. The large MCE and RC are achieved in both specimens. For a field change of 3 T, the MCE and RC reach the largest values of 5.8 J /kg K and 127.6 J/kg for x=0 composition and 4.3 J /kg K and 72.1 J/kg for x=4 composition. The broadening of the MCE curves is likely associated with the ordering of the magnetic moments of Eu that occurs below 10 K. The large values of MCE and RC, in addition to the absence of thermal and field hysteresis indicate that these clathrate materials are very interesting for cryogenic magnetic refrigeration applications. [ABSTRACT FROM AUTHOR]

Theoretical saturation magnetization and magnetocrystalline anisotropy energy (MAE) of τ-phase (face-centered tetragonal) Mn50Al50 alloy were obtained by first principles calculations, and the alloy was fabricated to compare the experimental values with the theoretical predictions. The calculated magnetic moment and MAE for τ-phase Mn50Al50 were 2.37) μg/ f.u. and 0.259 meV/f.u. (1.525×106 J/m3), respectively, which result in the maximum energy product (BH)max of 12.64 MG Oe and the magnetocrystalline anisotropy field of 38 kOe. The saturation magnetization for τ-phase Mn54Al46 alloy was measured to be 98.3 emu/g, which gives 4.7 MG Oe of (BH)max. The magnetization is about 70% of the theoretical value of 144 emu/g. [ABSTRACT FROM AUTHOR]

The effects of Zn2+ and Ti4+ substitutions on the microstructure and properties of low temperature sintered M-type barium hexaferrites Ba(ZnTi)xFe12-2xO19 have been studied in order to adapt the development of low temperature cofired ferrites technology and produce circulators with a multilayer process. It is found that part of Zn2+ ions can enter into 2b sublattice and the saturation magnetization of the samples decrease when x increases. The additive of 3-5 wt % Bi2O3.B2O3.SiO2 glass lowers the sintering temperature to about 900 °C, which is ideal for cofiring with silver paste. Scanning electron microscope and x-ray diffraction analysis show that the samples have excellent crystalline grains with a uniform size about 1.0 μm. A high density of 4.85 g/cm3 is obtained in the samples sintered at 900 °C with 5 wt % glass additive. Magnetic measurements show that the saturation magnetization reaches 63.5 emu/g (about 308 kA/m) at 900 °C and increases as the sintering temperature arises. [ABSTRACT FROM AUTHOR]

Here we report the single phase nanostructured Gd3Fe5O12 garnets with different grain sizes (bulk, 75, 47, 35, and 22 nm) were prepared by ball milling for various milling times. Both the average grain size and the lattice parameter were estimated from the x-ray diffraction line broadening. The 57Fe Mössbauer spectra were recorded at 300 and 77 K for the samples with different grain sizes clearly evidenced the formation of Fe2+ ions induced by milling and the content of Fe2+ increases with milling time. At 4.2 K, a significant increase in saturation magnetization (+11%) has been observed for the 47 nm particles. The magnetization is strongly applied field dependent and no saturation effect is observed even at fields as high as of 320 kOe. The results presented here have been explained in terms of the key role played by the Fe2+ ions. [ABSTRACT FROM AUTHOR]

To find out whether experimental magnetometric demagnetizing factors for disk samples of permalloy are valid for other magnetic materials with significant values of coercive field, we measured demagnetizing factors for disk samples of 1095 (high carbon) steel shim stock (Hc ≃45 Oe), and for cold-rolled pure nickel (Hc≃23 Oe). The observed demagnetizing factors for steel agree well with those for permalloy but the values for cold-rolled nickel do not, at least for disk samples with diameter-to-thickness ratios d/ t greater than 100. The criterion for agreement appears to be a hysteresis loop (M versus H) with straight, parallel sides up to at least half the saturation magnetization, implying a magnetization process controlled by the magnitude of the demagnetizing field. [ABSTRACT FROM AUTHOR]

Co-Fe alloys with a high saturation flux density Bs are used as soft magnetic materials in various microelectromechanical system applications. The electroplating process to deposit this material was widely researched. This paper describes experimental investigations to optimize the Co-Fe electroplating process. Besides the high saturation flux density Bs and other magnetic properties, mechanical and chemical properties like low film stress and good corrosion resistance also have to be considered. In these experiments, test electrolytes with different additives were used. The main purpose of those additives is to avoid the oxidation of Fe2+ to Fe3+ in the electrolyte to minimize the formation of Fe(OH)3 and its integration in the deposited film. Vibrating sample magnetometer measurements were applied to characterize the magnetic properties. The composition of Fe and Co in the deposited film was determined by energy dispersive x-ray spectroscopy. An electron probe microanalyzer was used to determine the impurities (O, S, and B) in the deposits. The results show different efficiencies of the applied additives improving the plating process. [ABSTRACT FROM AUTHOR]

Increasing atmospheric carbon dioxide and its dissolution in seawater have reduced ocean pH and carbonate ion concentrations, with potential implications on calcifying organisms. To assess the response of large Caribbean benthic foraminifera to low carbonate saturation conditions, we analyzed benthic foraminifers' abundance and relative distribution in surface sediments in proximity to low-carbonatesaturation submarine springs and at adjacent control sites. Our results show that the total abundance of large benthic foraminifera was significantly lower at the low-pH submarine springs than at control sites, although responses were species specific. The relative abundance of high-magnesium, porcelaneous foraminifera was higher than that of hyaline foraminifera at the low-pH springs due to the abundant Archaias angulatus, a chlorophyte-bearing foraminifer, which secretes a large and robust test that is more resilient to dissolution at low-calcite saturation. The different assemblages found at the submarine springs indicate that calcareous symbiont-barren foraminifera are more sensitive to the effects of ocean acidification than agglutinated and symbiontbearing foraminifera, suggesting that future ocean acidification will likely impact natural benthic foraminifera populations. [ABSTRACT FROM AUTHOR]

Clothing comfort is determined by multiple material and design factors. Wetness at the skin-clothing interface mainly impacts wear comfort. The current study investigated the combined effect of fabric contact area, fabric absolute sweat content and fabric moisture saturation percentage on wetness and stickiness sensations, during exercise. Moreover, factors causing wear (dis)comfort during exercise were identified. Higher fabric saturation percentage induced greater stickiness sensation, despite lower fabric contact area and absolute sweat content (typically associated with lower stickiness). Wetness perception did not change between fabrics with different saturation percentages, contact areas and sweat contents. Therefore, fabric saturation percentage mainly affects stickiness sensation of wet fabrics, overruling the impact of fabric contact area and absolute sweat content. No overall model of wear discomfort across all data could be developed, however, models for different time points were produced, with texture and stickiness sensations being the best predictors of wear discomfort at baseline and during exercise, respectively. This suggests that the factors determining clothing (dis)comfort are dynamics and alter importance during exercise activity. [ABSTRACT FROM AUTHOR]

The equation of state of an ideal collection of bosons in the low-density and high-density regime are found using the method of cluster expansion with Mayer's generating function. The saturation density and the other thermodynamic properties are calculated by the application of Mayer's convergence of the partition function. By calculating the value of saturation density from the singularity of the partition function series, the differences between the Mayer series convergence and the virial series convergence for ideal bosons are also established. [ABSTRACT FROM AUTHOR]

Abstract In cold nuclear matter, the shifts in the mass and current-meson coupling as well the vector self energy of the exotic X (3872) are calculated using the diquark–antidiquark current within the framework of the in-medium two-point QCD sum rule. At the rest frame of the medium, the three momentum of the considered particle is fixed to remove the contributions of the particles with negative energy. In the calculations, we include the in-medium condensates of quark–quark, gluon–gluon and quark–gluon. It is observed that, the shift due to the nuclear matter is negative and is about 25% when the saturation density is used. Such shift is considerably large and comparable with the nucleon' mass shift due to the nuclear medium. The negative shift in the current-meson coupling due to nuclear matter is approximately 10%. At the saturation density, the vector self energy of the exotic X (3872) state is found to be Σ υ = 1.31 GeV. It is shown that the mass, current-meson coupling and vector self energy of X (3872) strongly depend on the density of cold nuclear matter. [ABSTRACT FROM AUTHOR]

Reservoirs are considered as important carbon source of the atmosphere, whilst, regional and global reservoir CO 2 quantification is hampered by data limitation and bias in spatial and temporal sampling. By deploying chamber measurements and employing the newly developed model of gas transfer velocity, CO 2 partial pressure ( p CO 2 ) and evasion in the main stem of the Three Gorges Reservoir (TGR) were investigated. The p CO 2 ranged from 429 to 8668 μatm with an average of 2511.6 ± 1721.3 μatm, 6.1-fold higher than the ambient air p CO 2 (mean: 410 μatm). All the samples were net CO 2 sources via water-air interface, displaying pronounced spatial and monthly variability. The CO 2 areal flux averaged 212.5 ± 120.1 mmol/m 2 /d in June, 123.3 ± 78.5 mmol/m 2 /d in July in the lotic TGR main stream, much higher than its lentic system, i.e., 79.6 ± 41.3 mmol/m 2 /d in November, and 76.3 ± 88.1 mmol/m 2 /d in March. Much lower k levels in the lentic reservoir surface resulted in lower CO 2 evasion rates. Furthermore, dam impoundment considerably altered the riverine carbon cycle, as reflected by the changing magnitude of CO 2 efflux and environmental controls of dissolved CO 2 . Precipitation and concurrent soil CO 2 influx exhibited a central role in controlling riverine p CO 2 , and respiration of allochthonous organic carbon was a secondary factor in the TGR lotic system, whilst, both in-stream metabolism and terrestrial inputs played crucial roles in controlling aqueous CO 2 in the TGR lentic system. In comparison, we provided key findings of k model and more reliable CO 2 quantification with a consideration of water level shifts and a complete coverage of spatial sampling. Our higher CO 2 emission (1.47 (1.16–2.13) Tg CO 2 /y) than previous studies called more field measurements to assess the resulting changes in CO 2 flux owing to dam operation and changing environment, and their implications for regional carbon budgets should be warranted. [ABSTRACT FROM AUTHOR]

Rotating-beam wind scatterometers exist in two types: rotating fan-beam and rotating pencil-beam. In our study, a generic simulation frame is established and verified to assess the wind retrieval skill of the three different scatterometers: SCAT on CFOSAT, WindRad on FY-3E and SeaWinds on QuikScat. Besides the comparison of the so-called 1st rank-solution retrieval skill of the input wind field, other Figure of Merits (FoMs) are applied to statistically characterize the associated wind retrieval performance from three aspects: wind vector root mean square error, ambiguity susceptibility, and wind biases. The evaluation shows that, overall, the wind retrieval quality of the three instruments can be ranked from high to low as WindRad, SCAT, and SeaWinds, where the wind retrieval quality strongly depends on the Wind Vector Cell (WVC) location across the swath. Usually, the higher the number of views, the better the wind retrieval, but the effect of increasing the number of views reaches saturation, considering the fact that the wind retrieval quality at the nadir and sweet swath parts stays relatively similar for SCAT and WindRad. On the other hand, the wind retrieval performance in the outer swath of WindRad is improved substantially as compared to SCAT due to the increased number of views. The results may be generally explained by the different incidence angle ranges of SCAT and WindRad, mainly affecting azimuth diversity around nadir and number of views in the outer swath. This simulation frame can be used for optimizing the Bayesian wind retrieval algorithm, in particular to avoid biases around nadir, but also to investigate resolution and accuracy through incorporating and analysing the spatial response functions of the simulated Level-1B data for each WVC. [ABSTRACT FROM AUTHOR]

Analyzing the 1 H NMR spectrum of d -glucose, the resonance frequencies of the anomeric protons of five d -glucose anomers could be determined in dependence on temperature. Besides, the relative concentrations of all cyclic d -glucose anomers could be quantified. Based on that, thermodynamic parameters were calculated. In addition, ring opening rate constants of all cyclic d -glucose anomers were measured for the first time using 1 H selective blind saturation transfer NMR spectroscopy. The results presented here give rise to the assumption that furanoid anomers highly influence the reactivity of total d -glucose. Finally, the complex anomeric equilibration curves for a freshly prepared solution of crystalline α- d -glucopyranose are presented. Based on that, it is hypothesized that the reactivity of a solution of a reducing sugar in general and d -glucose in particular depends on time until the thermodynamic equilibrium state is reached. [ABSTRACT FROM AUTHOR]

In this paper, the condensation heat transfer of hydrocarbon mixtures refrigerant (methane/propane) flowing in a helical tube with 10 mm hydraulic diameter was investigated by experiments and numerical simulations. The experiments were conducted at mass flux of 200–400 kg/(m 2 ·s), saturation pressure of 0–4Mpa and heat flux of 4.8–5 kW/m 2 . Also, the effects of mass flux, vapor quality, and saturation pressure on heat transfer coefficient were studied. It was observed that the heat transfer coefficients increased with the increase of mass flux and vapor quality, while the heat transfer coefficients generally decreased as the saturation pressure increased. Meanwhile, annular flow(half-annular flow, annular flow) and Non-annular flow patterns (slug flow, stratified flow, wavy flow, transition flow) were observed during the condensation of methane/propane mixtures refrigerant. And a new flow pattern transition line for hydrocarbon refrigerants condensation process was proposed. The condensation heat transfer coefficient data were compared with several existing correlations, and a modified heat transfer correlation for different flow patterns was proposed, which predicted the results well with a mean absolute error of 10.03%. [ABSTRACT FROM AUTHOR]

Abstract The Ni 0.5- x Mo x Zn 0.5 Fe 2 O 4 (x = 0.00, 0.005, 0.01, 0.015 and 0.02) ferrites have been synthesized by the sol-gel auto-combustion method. The crystal structure, surface morphology, magnetic properties, and cation distribution of the ferrites have been investigated by X-ray powder diffraction (XRD), scanning electron microscopy (SEM), and vibrating sample magnetometer (VSM). The lattice parameter initially decreases and then sharply increases. According to the analysis of SEM and magnetic properties, there is the second phase NiO existing in the sample of x = 0.02. Cation distribution estimated from XRD, SEM and magnetic properties analyses suggests that Mo6+ ions occupy the tetrahedral sites, and more and more Fe2+ ions appear in the samples with the addition of Mo content. The saturation magnetization (M s) and initial permeability (μ i) of samples increase firstly, and then sharply decrease with increasing Mo6+ content from x = 0.005 to x = 0.02. The Ni 0.485 Zn 0.5 Mo 0.015 Fe 2 O 4 ferrite has the maximum M s of 82.2 emu/g and μ i of 86. Meanwhile, it presents the best microstructure, the largest bulk density and the lowest porosity. [ABSTRACT FROM AUTHOR]

Motor oil classification is important for quality control and the identification of oil adulteration. In this work, we propose a simple, rapid, inexpensive and nondestructive approach based on image analysis and pattern recognition techniques for the classification of nine different types of motor oils according to their corresponding color histograms. For this, we applied color histogram in different color spaces such as red green blue (RGB), grayscale, and hue saturation intensity (HSI) in order to extract features that can help with the classification procedure. These color histograms and their combinations were used as input for model development and then were statistically evaluated by using linear discriminant analysis (LDA), quadratic discriminant analysis (QDA), and support vector machine (SVM) techniques. Here, two common solutions for solving a multiclass classification problem were applied: (1) transformation to binary classification problem using a one-against-all (OAA) approach and (2) extension from binary classifiers to a single globally optimized multilabel classification model. In the OAA strategy, LDA, QDA, and SVM reached up to 97% in terms of accuracy, sensitivity, and specificity for both the training and test sets. In extension from binary case, despite good performances by the SVM classification model, QDA and LDA provided better results up to 92% for RGB-grayscale-HSI color histograms and up to 93% for the HSI color map, respectively. In order to reduce the numbers of independent variables for modeling, a principle component analysis algorithm was used. Our results suggest that the proposed method is promising for the identification and classification of different types of motor oils. [ABSTRACT FROM AUTHOR]

The acoustic properties of a ground surface are well known to be affected strongly by soil moisture contents. Many studies have been conducted to quantify the effects through in-situ and laboratory measurements. The soil moisture is also well known to be influenced by continuous variability of meteorological elements such as rainfall, sunshine, and air temperature. Therefore, it is expected that the meteorological variability alters ground acoustic properties over time. For this study, an in-situ measurement campaign was held during July 2014 to January 2015 at a site in Niigata, Japan. An automatic weather station observed meteorological elements at 1-minute intervals. A buried soil moisture sensor measured water saturation in the ground near the station at 5-minute intervals. The acoustic absorption coefficient of the same ground position was measured once a day using an in-situ measurement technique. The observations showed that the absorption coefficient of the ground surface had variations with multiple timescales from days to months and seasons. Two-stage models of the influence of the weather on the absorption coefficient of the ground surface were derived from the data. The first stage models the short- and long-term effects of rainfall and the air temperature on the water saturation of the soil. The second stage models the effects of water saturation on the absorption coefficient of the ground. The derived models were found to explain the long-term and approximately half of the short-term variation of the acoustic absorption. [ABSTRACT FROM AUTHOR]

This paper presents multiscale modeling substantiated with experimental aspects of state, filtration, and motion of the gas-liquid mixtures involving phase transition regions in concentrated volumes applicable to porous media and pipe flows. Based on physics, it is confirmed analytically that actual levels of underpressure in gas-liquids systems are considerably above traditional understanding of saturation pressure at which gas emission from the liquid and its dissolution in the liquid in a form of embryos can occur. It is demonstrated that these processes are not equilibrium processes, and they can also occur on nanoscales and microscales. Thermo-hydrodynamic analyses and experimental investigation of the gas-liquid systems in areas of phase transition presented here have resulted in useful equations governing such flows in filtration in the porous media and in straight pipes. [ABSTRACT FROM AUTHOR]

The sol–gel auto-combustion method was applied for preparation of SrFe12O19 magnetic nanoparticles (MNPs). Then, the prepared SrFe12O19 was analyzed by VSM, FT-IR, SEM, N2 adsorption-desorption and XRD pattern. According to the hysteresis loops of SrFe12O19 MNPs, its magnetic saturation was about 79 emu/g and also it is a typical feature of ferromagnetic compound. SEM image showed semi-spherical particles with average size of 70 nm. The BET surface area of SrFe12O19 MNPs was 10.4 m2/g. Moreover, the catalytic activity of SrFe12O19 MNPs was tested for the first time toward the Betti reaction. The results showed that it is an efficient catalyst which can be easily separated from the reaction mixture using an external magnet and gives the pure products in high yields within short reaction time. [ABSTRACT FROM AUTHOR]

Highlights • Economized vapor injection (EVI) investigated for application in extreme hot climates. • A packaged air-conditioner retrofitted and tested with an EVI system. • EVI system reduced the compressor discharge temperature and improved COP. • A detailed implicit EVI cycle model developed, tuned, and validated. • At 51.7 °C, system optimization increased cooling capacity by 22.3% and COP by 17.3%. Abstract Operating packaged air conditioning systems at extremely high temperature ambient conditions result in severe performance degradation. In this paper, vapor injection (VI) with economization is proposed to improve system performance. An Environmental Control Unit (ECU) operating with R-407C has been retrofitted with an economized vapor injection (EVI) system and experimentally characterized in side-by-side psychrometric chambers. The performance of the EVI system for superheated and saturated injection conditions were compared to the case of without injection at different operating conditions. The results showed that the EVI system reduced the compressor discharge temperature by up to 5° C, and improved the cooling capacity and COP by up to 12.7% and 3.1%, respectively. The experimental data have been used to develop, tune, and validate a detailed steady-state cycle model. At last, the model has been employed to optimize the economizer geometry in order to maximize the system COP under such extreme weather conditions. [ABSTRACT FROM AUTHOR]

Highlights • Saturated solution temperature of oil sump mixture was proposed and calculated. • Impact of R290 solubility and mixture viscosity in the oil sump were investigated. • Viscosity of R290/NM100 MO mixture was enough to lubricate the journal bearings. • Suggestions about the optimization of suction superheat degree were made. Abstract The solubility of R290 in the oil and the R290/oil mixture viscosity in the oil sump of rotary compressors used in air conditioner are important parameters affecting the compressor reliability, system performance and R290 charged mass in system. In the study, a set of experiments were carried out in both compressor performance test platform and system psychrometric chambers for an R290 rotary compressor with mineral oil having high viscosity. The dynamic viscosity and temperature of R290/oil mixture at some points within the oil sump of compressor, besides the temperature on shell outside corresponding oil sump and the performance parameters of compressor or air conditioner were measured under different cooling and heating conditions. The variation ranges of oil sump mixture viscosity and R290 solubility were given. The saturated solution temperature and superheat degree of oil sump mixture were proposed and calculated. The effect of compressor suction superheat on the oil sump superheat and its effect on solubility and viscosity was analyzed. A greater suction superheat degree was suggested for an R290 air conditioner with mineral oil in terms of compressor reliability because of the low discharge temperature of R290 compressor. [ABSTRACT FROM AUTHOR]

Highlights • Effect of the inclination angle on the heat transfer coefficient and pressure drop. • Condensation heat transfer coefficient increased with increasing mass flux and vapour quality. • Condensation heat transfer coefficient increased with the decrease in saturation temperature. • Pressure drop along the tube increased with the decrease in saturation temperature. • An optimum inclination-angle-region of −30 °< β < −15° was observed in the simulation. Abstract In this study, numerical simulations of the condensation of R134a inside an inclined smooth tube are conducted. The effects of different parameters such as saturation temperature, tube inclination angle, vapour quality, and mass flux, on variations of the condensation heat transfer coefficient and pressure drop along the tube were investigated. The simulations were performed at a uniform heat flux of 5050 W/m2, mass fluxes of 100–400 kg/m2s, saturation temperatures of 30–50 °C, vapour qualities of 0.1–0.9, and inclination angles of −90 to + 90° It was assumed that the flow field was three-dimensional, transient, and turbulent. The volume of fluid model was used to solve the governing equations. The simulated results for the condensation heat transfer coefficient and pressure drop showed good correlation with the available experimental data. The results also demonstrated that the condensation heat transfer coefficient and pressure drop along the tube increased with decreasing saturation temperature, and increasing mass flux and vapour qualities. It was also determined that there was an optimum inclination-angle-range, −30 to −15°, in which the condensation heat transfer coefficient attained a maximum value. [ABSTRACT FROM AUTHOR]

Abstract A dynamic centrifuge model test of mildly sloping ground was conducted at Zhejiang University according to the LEAP-GWU-2015 experiment specifications. A 5-degree slope consisting of a saturated medium dense Ottawa F-65 sand was prepared by air pluviation method in rigid container, which simulated a prototype with a 20 m length and 4 m depth under 26 g centrifugal acceleration. The model was subjected to three smaller and two destructive motions. Test data and preliminary analyses of model responses during multiple shakings are presented. In-flight measurement of shear wave velocity by bender elements was used to characterize the evolution of soil state. Acceleration response spectra were presented and site amplification effects were observed. Shear stress-strain loops were calculated from acceleration records, and asymmetric dilatancy in the sloping ground was observed during liquefaction. Generation and dissipation of excess pore pressure were depicted. Large liquefaction-induced ground displacements were measured and analyzed. This study provides valuable data and delivers some important observations of liquefaction responses of a sloping ground. Highlights • In-flight S-wave based monitoring of soil state and P-wave based check of saturation degree. • Frequency dependent site amplification effects were observed during all input motions. • Asymmetric dilatancy in upslope and downslope directions was observed during liquefaction. • Large vertical and horizontal displacements were measured and analyzed. [ABSTRACT FROM AUTHOR]

Chemical activity quantifies the energetic level of an organic compound relative to its pure liquid [0–1], and several studies have reported that baseline toxicity generally requires chemical activities of 0.01–0.1. The first aim was to challenge this chemical activity range for baseline toxicity. Algal growth inhibition data (median effective concentrations, EC 50 ) were compiled from two recent studies and included 108 compounds categorised as non-polar (mode of toxic action, MOA1) and polar (MOA2) narcotics. These data were linked to chemical activity by (1) plotting them relative to a regression for (subcooled) liquid solubility (S L ), which served as visual reference for chemical activity of unity and (2) determining EC 50 /S L ratios that essentially equal median effective chemical activity (Ea 50 ). Growth inhibition required chemical activity >0.01 for MOA1 and >0.001 for MOA2 compounds. The second aim was to identify compounds exerting excess toxicity, i.e., when growth inhibition occurred at chemical activity <0.001. From a recent review with 2323 data entries, 315 EC 50 values passed our selection criteria. 280 of these EC 50 values were within or near the baseline toxicity range (Ea 50 >0.001), and 25 compounds were found to exert excess toxicity (Ea 50 <0.001). Of these compounds, 16 are pesticides or precursors. Methodologically, this study includes two methods for translating EC 50 values into the chemical activity framework, each having advantages and limitations. Scientifically, this study confirms that baseline toxicity generally requires chemical activities of 0.01–0.1 and extends the application of the chemical activity approach beyond baseline toxicity, by demonstrating its utility to identify compounds that exert excess toxicity. [ABSTRACT FROM AUTHOR]

Purpose The high chemical shift separation at 9.4 T allows for selective saturation of proton pools in exchange with water protons. For the first time, highly selective and comprehensive chemical exchange saturation transfer (CEST) experiments were performed in the human brain at 9.4 T. This work provides insight into CEST signals in the human brain in comparison with existing animal studies, as well as with CEST effects in vivo at lower field strengths. Methods A novel snapshot-CEST method for human brain scans at 9.4 T was optimized and employed for highly-spectrally-resolved (95 offsets) CEST measurements in healthy subjects and one brain tumor patient. Reproducibility and stability between scans was verified in grey and white matter after B 0 , B 1 , and motion correction of the acquired 3D CEST volumes. Two-step Lorentzian fitting was used to further improve separation of spectrally discernible signals to create known and novel CEST contrast maps at 9.4 T. Results At a saturation power of B 1  = 0.5 μT most selective CEST effects could be obtained in the human brain with high inter-scan reproducibility. While contrast behavior of previously measured signals at lower field, namely amide-, guanidyl- and NOE-CEST effects, could be reproduced, novel signals at 2.7 ppm, and −1.6 ppm could be verified in healthy subjects and in a brain tumor patient for the first time. Conclusion High spectral resolution chemical exchange saturation transfer at 9.4 T allows deeper insights into the Z-spectrum structure of the human brain, and provides many different contrasts showing different correlations in healthy tissue and in tumor-affected areas of the brain, generating hypotheses for future investigations of in-vivo-CEST at UHF. [ABSTRACT FROM AUTHOR]

Purpose: The study compares glycosaminoglycan chemical exchange saturation transfer (gagCEST) imaging of intervertebral discs corrected for solely B0 inhomogeneities or both B0 and B1 inhomogeneities.Methods: Lumbar intervertebral discs of 20 volunteers were examined with T2-weighted and gagCEST imaging. Field inhomogeneity correction was performed with B0 correction only and with correction of both B0 and B1. GagCEST effects measured by the asymmetric magnetization transfer ratio (MTRasym) and signal-to-noise ratio (SNR) were compared between both methods.Results: Significant higher MTRasym and SNR values were obtained in the nucleus pulposus using B0 and B1 correction compared with B0-corrected gagCEST. The GagCEST effect was significantly different in the nucleus pulposus compared with the annulus fibrosus for both methods.Conclusion: The B0 and B1 field inhomogeneity correction method leads to an improved quality of gagCEST imaging in IVDs compared with only B0 correction. [ABSTRACT FROM AUTHOR]

We report the magnetostriction and 〈0 0 1〉 texture of anisotropic polycrystalline CoFe2O4. Slurries with well dispersion and low sintering shrinkage are aligned by the magnetic field of 2 T and sintered to prepare highly 〈0 0 1〉 textured CoFe2O4 samples. For the anisotropic sample, benefiting from the 〈0 0 1〉 fiber texture, a higher magnetostrictive property is achieved than that of isotropic polycrystalline sample prepared by dry compaction. The maximum magnetostriction up to −500 ppm at 1000 Oe is obtained, which reaches 85% of the highest value in single crystal (λ 100  = −590 ppm). Meanwhile, the maximum strain-field derivative is also improved to −0.97 ppm/Oe at 250 Oe, which is highly beneficial for sonar detector and force sensor applications. [ABSTRACT FROM AUTHOR]

Abstract Dihadron angular correlations in forward pA collisions have been considered as one of the most sensitive observables to the gluon saturation effects. In general, both parton shower effects and saturation effects are responsible for the back-to-back dihadron angular de-correlations. With the recent progress in the saturation formalism, we can incorporate the parton shower effect by adding the corresponding Sudakov factor in the saturation framework. In this paper, we carry out the first detailed numerical study in this regard, and find a very good agreement with previous RHIC pp and dAu data. This study can help us to establish a baseline in pp collisions which contains little saturation effects, and further make predictions for dihadron angular correlations in pAu collisions, which will allow to search for the signal of parton saturation. [ABSTRACT FROM AUTHOR]

Abstract From general Fermi liquid theory arguments, we derive correlations among the symmetry energy (J), its slope parameter (L), and curvature (K sym) at nuclear matter saturation density. We argue that certain properties of these correlations do not depend on details of the nuclear forces used in the calculation. We derive as well a global parametrization of the density dependence of the symmetry energy that we show is more reliable, especially at low densities, than the usual Taylor series expansion around saturation density. We then benchmark these predictions against explicit results from chiral effective field theory. [ABSTRACT FROM AUTHOR]

This work presents two complementary approaches (for low and high desaturation) to study tritiated water (HTO) diffusion through unsaturated cement-based materials. The first approach was based on through-diffusion experiments where suction was controlled by osmosis. In the second approach, diffusion experiments were performed in humidity chambers controlled by under-saturated saline solutions. Results revealed a decrease of effective diffusion coefficient by a factor of 10 from 100% to 23% of saturation degree. Comparison with gaseous H 2 suggests that HTO diffuses through unsaturated cement-based materials at rates 4 orders of magnitude lower. [ABSTRACT FROM AUTHOR]

This work presents two complementary techniques to study 36 Cl and stable chloride diffusion through unsaturated cement-based materials for saturation degrees ( S w ) ranging from 0.18 to 1. The first technique is based on steady-state through-diffusion method where suction (up to 9 MPa) is controlled using osmosis process. In the second technique, in-diffusion experiments are performed by putting into contact a spiked-fresh-cement paste with a CEM-V/A-hardened-cement paste (HCP) sample (initial water to cement ratio of 0.4) having a given water saturation imposed by saline solution method. After a controlled diffusion time, the 36 Cl activity profiles within the samples are acquired by means of the abrasive peeling method and 36 Cl activity is determined by liquid scintillation counting (LSC) technique. The application of the first technique resulted in data showing a sharp decrease of the effective diffusion coefficient ( D e ) (by a factor of ten) between the experiments done on the fully-saturated HCP sample and the HCP sample at S w  = 0.85. Moreover, duplicate in-diffusion experiments carried out on HCP samples partially-saturated at S w  = 0.86 provided 36 Cl D e range well bracketing the one determined by the first approach at S w  = 0.85. Four other in-diffusion experiments were thus performed on HCP samples with saturation degrees down to 0.18. Interpretation of the experimental results showed a very small decrease of D e values for S w from 0.74 to 0.41 and a sharp decrease for S w from 0.41 to 0.18. Lastly, comparison with the diffusive behavior of tritiated water (HTO) through unsaturated CEM V/A HCP samples clearly indicated that diffusion of chloride was more affected by desaturation than HTO. Its ionic form would restrict chloride to the liquid phase whom continuity is broken when dehydration is strong enough. [ABSTRACT FROM AUTHOR]

Abstract Metal organic frameworks (MOFs) have diverse applications in adsorption/separation fields. However, little is known about MOFs as adsorbents for the adsorption of Au(III) from aqueous solutions. In this work, a highly porous MOFs, ZIF-8, was modified by thiourea (TU) via coordination-based post-synthetic modification strategy. Compared with pristine ZIF-8, the TU functionalized ZIF-8, TU*ZIF-8, exhibited a remarkable Au(III) adsorption ability with a saturation adsorption capacity of 4262.8 mg/g although its surface area and pore volume decreased with TU loading. Interestingly, the adsorption efficiency of Au(III) was >99% with a broad Au(III) concentration range of 50–400 mg/L using only 20 mg TU*ZIF-8. Meanwhile, TU*ZIF-8 showed an encouraging selectivity for Au(III) in the presence of some metal ions such as Cu(II), Cr(VI), Pb(II), Cd(II), Mn(II), Mg(II), and Co(II). The improved adsorption of Au(III) on TU*ZIF-8 is explained by the synergistic effect of electrostatic interaction and coordination interaction. Particularly, the coordination interaction between Au(III) and TU of TU*ZIF-8 plays a major role in the Au(III) adsorption process of TU*ZIF-8. This work suggests a potential application of functionalized MOFs for the efficient recovery of gold from aqueous solutions. Graphical abstract Unlabelled Image Highlights • TU*ZIF-8 was prepared via coordination between TU and CUSs of ZIF-8. • Saturation adsorption capacity of TU*ZIF-8 for Au(III) is 4262.8 mg/g. • Ionic strength and metal ions almost did not influence the adsorption of Au(III). [ABSTRACT FROM AUTHOR]

Ozone reacted with the polybenzimidazole (PBI) film surface and X-ray photoelectron spectroscopy (XPS) detected a rapid increase in O atom concentration up to a saturation level of 27 ± 1 atomic %. Atomic force microscopy measurements showed little change in surface roughness. The water contact angle of the treated film decreased by ca. 60% compared to untreated PBI film indicating an increase in hydrophilicity and hydrogen bonding due the formation of the polar oxygenated functional groups. With treatment, the curve fitting of the XPS chemical states showed a decrease in the C-C sp2, C-C sp3, and C=N functional groups, and an increase in C-N, C=O, O-C=O, O-(C=O)-O, and N-C=O moieties which were explained using mechanisms associated with the dissociation of the primary ozonide formed from the addition of ozone to the C=C and C=N bonds and reaction with the amine groups in PBI. Washing the treated surface with water partially washed away the O concentration which indicated the formation of a weak boundary layer due to the breakage of bonds in the decomposition of the primary ozonide. [ABSTRACT FROM AUTHOR]

In the North Pacific, variations in isopycnal depth influence the biogeochemical characteristics of the water column and the aragonite saturation horizon (ZΏa) during interannual events. The objective of this study was to assess the effect of the 2011 La Nina conditions on ZΏa in Todos Santos Bay (Baja California, Mexico) and surrounding waters. The results showed that ZΏa variability was modulated by the intensity of interannual conditions and by the water masses that were present in the region. Subarctic Water predominated in the upper 200 m with anomalous characteristics, such as low temperature and low salinity. Also, isopycnals shoaled toward the coast and ZΏa was thus ~30 m in the nearshore area, in contrast with the oceanic region, where ZΏa was ~150 m. Prior to this study, there were no records of ZΏa in Todos Santos Bay, nor were there any records of its shallowness. [ABSTRACT FROM AUTHOR]

A unified model for gas slip flow through circular and angular pores in both single phase flow and two‐phase flow conditions is developed, and the effect of water saturation on gas slippage factors in different pore shapes are revealed. For circular pores, the water saturation retains as thin film binding on pore surfaces without changing the shape of the cross section, and the hydraulic diameters continuously reduce as water saturation increases, directly leading to an increase in the slippage factor. However, for angular pores, the water saturation retains as both films at boundaries and condensations at corners, and the film‐water and corner‐water gradually change their cross‐section shape (from sharp corners to round corners), which further affects the gas slip behavior. Due to the presence of round corners, the ratio of the cross‐sectional area and perimeter, which can also be regarded as the reciprocal of a specific surface area, can even increase at a low water saturation condition. Thus the collisions between gas molecules and pore boundaries weaken, resulting in a slight reduction in the gas slippage factor. This interesting finding in the angular pore case directly explains the contradiction of the published experimental results with the general knowledge (i.e., the gas slip factor always increases as water saturation increases). Thus, the validity of the common assumption regarding actual porous media as capillaries with a circular cross‐section must be considered more carefully. © 2018 American Institute of Chemical Engineers AIChE J, 64: 3529–3541, 2018 [ABSTRACT FROM AUTHOR]

A simple protocol was developed to measure seawater calcium carbonate saturation states (Ω spec ) spectrophotometrically. Saturation states are typically derived from the separate measurement of two other carbon system parameters, with each requiring unique instrumentation and often complex measurement protocols. Using the new protocol, the only required equipment is a thermostatted laboratory spectrophotometer. For each seawater sample, spectrophotometric measurements of pH (visible absorbance) are made in paired optical cells, one with and one without added nitric acid. Ultraviolet absorbance is measured to determine the amount of added acid based on the direct proportionality between nitrate concentration and UV absorbance. Coupled measurements of pH and the alkalinity change that accompanies the nitric acid addition allow calculation of a seawater sample's original carbonate ion concentration and saturation state. These paired absorbance measurements yield Ω spec (and other carbonate system parameters), with each sample requiring about 12 min processing time. Initially, an instrument-specific nitrate molar absorptivity coefficient must be determined (due to small but significant discrepancies in instrumental wavelength calibrations), but thereafter no further calibration is needed. In this work, the 1σ precision of replicate measurements of aragonite saturation state was found to be 0.020, and the average difference between Ω spec and Ω calculated conventionally from measured total alkalinity and pH (Ω calc ) was −0.11% ± 0.96% (a level of accuracy comparable to that obtained from spectrophotometric measurements of carbonate ion concentration). Over the entire range of experimental conditions, 0.97 < Ω < 3.17 ( n  = 125), all measurements attained the Global Ocean Acidification Observing Network's “weather level” goal for accuracy and 90% attained the more stringent “climate level” goal. When Ω spec was calculated from averages of duplicate samples ( n  = 56), the precision improved to 0.014 and the average difference between Ω spec and Ω calc improved to −0.11% ± 0.73%. Additionally, 97% of the duplicate-based Ω spec measurements attained the “climate level” accuracy goal. These results indicate that the simple measurement protocol developed in this work should be widely applicable for monitoring fundamental seawater changes associated with ocean acidification. [ABSTRACT FROM AUTHOR]

This paper summarizes different aspects of arsenic mineralogy and geochemistry in the Wiśniówka acid mine drainage (AMD) area, south-central Poland. The basic source of this metalloid in AMD water bodies is micro-grained pyrite that forms two different mineralized zones within the Upper Cambrian rock formation. Due to specific textural and geochemical characteristics, this mineral undergoes rapid oxidation on exposed quarry walls and unvegetated tailings piles, thus contributing to elevated arsenic concentrations in acid pit lakes and ponds, and locally intermittent pools. The latter were highlighted by the highest As levels reaching even 370 mg/L. Of the three AMD large reservoirs, the Podwiśniówka (eastern) lake revealed distinctly raised As concentrations varying from 7.02 to 22.2 mg/L. Another interesting water body is the Marczakowe Doły acid pond showing diverse seasonal As concentration patterns in colloids and a water column. Results of geochemical modeling showed that the saturation indices (SI) of hematite and goethite exhibited the highest values (range of 6.96 to 12.84 and 2.47 to 5.39, respectively) tending to precipitate in all the water bodies examined. In addition, the positive SI values of nanosized ε-Fe 2 O 3 (1.64 to 4.13) and schwertmannite (0.90 to 2.10) were found only in the Wiśniówka Duża and Marczakowe Doły acid waters. Laboratory experiments revealed that the best chemical and cost-effective method (out of the limited number of options) of arsenic removal from the AMD waters examined was the use of high-grade powdered limestone (fraction 0.0–0.09 mm) or more effective although more expensive limewater (calcium hydroxide). The positive SI values of hematite, goethite, ε-Fe 2 O 3 and schwertmannite of neutralized solutions suggest that these minerals should precipitate. Due to diverse concentrations in the examined rock series, arsenic has been used for fingerprinting “hot” places within the mining and neighboring areas, as well as for predicting the directions and effects of strip mining for quartzites. The As signature can also be applied to monitor a detrimental AMD impact on local surface and underground waters. [ABSTRACT FROM AUTHOR]

From research and field development, the threshold pressure gradient (TPG) in tight formations is required before the fluid starts to flow. This paper addresses the different factors that affect the TPG in tight sandstone gas reservoirs with high water saturation. First and foremost, the petrophysical properties were obtained through the following tests: X ray diffraction, scanning electron microscope and nuclear magnetic resonance using cores from Sulige gas field in China. Secondly, the TPG experimental investigations were performed using air bubble method, and a TPG correlation was obtained considering the influences of permeability, connate water and movable water. Finally, a gas production model was established with the TPG, slip and diffusion effects taken into account, and its applications were discussed using actual reservoir parameters. The results showed that the cores have plenty of clay minerals and high connate water saturation. Besides, the throat radii from NMR mainly are distributed between 0.0004 and 0.1 µm, with a few between 0.1 and 0.4 µm. The clay depositions decrease the pore and throat diameters, which result in Jamin effect. The experimental results showed that the TPG exists at the connate water saturation, and increase exponentially with either an increase in dimensionless water saturation or decrease in permeability. The IPR curves showed the TPG effect on gas production is very serious i.e. production loss degree decreases especially at high bottom hole pressure, and the production loss degree decreases as the bottom hole pressure decreases. The greater the water saturation or the smaller the permeability, the greater the production loss degree. In addition, the TPG affects the intercept of the abscissa of the flow curve, and the slope of the curve decreases as water saturation increases. [ABSTRACT FROM AUTHOR]

Abstract In the submarine setting pyroclast cooling and saturation, by controlling the buoyancy of individual clasts and surrounding fluid, exert fundamental controls on the dispersal and fate of volcanic material. In this study we use laboratory experiments to understand and quantify how hot and air-filled pyroclasts cool and saturate in liquid water. By measuring internal temperature and clast submerged weight in over thirty experiments, we find that pumice cools and saturates in two stages. We observe that the first stage is marked by much higher rates of cooling and saturation than the second stage and that the transition between stages is sharp. We propose conceptual and quantitative models for each stage of pyroclast cooling and saturation. Specifically we argue that the first stage is defined by the presence of internal steam. That is, hot pyroclasts ingest liquid water and generate steam. Once a clast's internal pore space is filled with steam, heat loss to the surroundings causes condensation of internal vapor and clast saturation. Stage 1 ends when all internal steam has condensed. We test this idea with a Stefan Model with advection and conclude that heat loss, rather than permeability, controls the saturation of pyroclasts above the boiling temperature. We find that permeability matters for air-filled clasts with initial temperatures below the boiling point. Stage 2 begins after all internal vapor has condensed and we propose that stage 2 cooling and saturation are controlled by heat conduction and thermal contraction of trapped gas, respectively. From our understanding of the processes that govern the stage 1 to 2 transition, we derive an empirical average pyroclast cooling rate of q = 7.5 ± 0.5 W cm−2. Finally, we develop quantitative models for cooling-controlled porous clast saturation and for buoyant clast rise to the ocean surface. We find that meter size clasts stay buoyant for more than 10 min - long enough to reach the surface from a depth of 1000 m. The models developed here test our understanding of clast-scale processes and demonstrate that - in hot and porous clasts - the details of internal texture do not matter because clast saturation, and thus buoyancy and fate in the water column, are governed by heat transfer. Highlights • Pumice cooling and saturation in water are examined with experiments. • Clasts cool at the same average rate of 7.5 ± 0.5 W cm−2. • Cooling rather than permeability controls the saturation of clasts above the boiling point. • Models demonstrate that meter size clasts stay hot and buoyant for > 10 minutes. [ABSTRACT FROM AUTHOR]

Summary: Stimulated emission depletion (STED) microscopy performed using continuous‐wave (CW) lasers has been investigated and developed by Willig et al. (Nature Methods, 2007, 4(11):915) for nearly a decade. Kuang et al. (Review of Scientific Instruments, 2010, 81:053709) developed the CW STED microscopy technique with 405 nm excitation and 532 nm depletion beams. In their research, Coumarin 102 dye was adopted and was found to be depletable. In this study, a parametric investigation of the depletion of Coumarin 102 dye is carried out experimentally. The influence of the excitation and depletion beam intensities and dye concentrations on the depletion efficiency are studied in detail. The results indicate the following: (1) The highest depletion occurs for the 100 μM Coumarin 102 solution, with a 1.4 μW excitation beam and a 115.3 mW depletion beam. (2) The minimum saturation intensity ( I s) of STED, that is 13 MW cm–2, is observed when the Coumarin 102 solution concentration is 10 μM. (3) I s values calculated directly from the depletion power derived with the cross‐sectional area due to the full‐width‐at‐half‐maximum (FWHM) of the depletion beam show poor accuracy, where I s may be overestimated. Thus, a correction factor for the cross‐sectional area is proposed. We also find that I s is not exactly constant for a fixed excitation beam power and dye concentration. This trend indicates that the conventional suppression function η ( x ) = e − ln ( 2 ) I STED ( x ) / I s derived from picosecond STED may cause errors in evaluating the depletion process in CW STED microscopy. [ABSTRACT FROM AUTHOR]

Valorization of avian by-products such as turkey ( Meleagris gallopavo ) proventriculus in the preparation of milk clotting enzymes constitutes an alternative to commercial rennet. The clotting enzyme of Meleagris gallopavo has been prepared by ammonium sulfate at 50% saturation followed by purification by cation-exchange fast protein liquid chromatography (FPLC), and determination of the clotting protease activity performed on milk incubated at 35 °C. The clotting fractions are concentrated and dialyzed against Tris/HCl pH 7.0 through a membrane with cutoff 8000 Da, and separated by anion-exchange FPLC. The coagulating fractions obtained by cation-exchange chromatography are also separated by reversed-phase high-performance liquid chromatography, which revealed only one fraction able to coagulate milk. Electrophoresis analysis revealed a band with apparent molecular mass of 36.5 kDa and seemed to correspond to pepsin-like enzyme according to primary sequence alignment analyses. Maximal clotting activity was obtained for optimal conditions of temperature of 55 °C and pH 5.4. [ABSTRACT FROM AUTHOR]

Background: Oxygen saturation monitoring for children receiving respiratory support is standard worldwide. No randomised clinical trials have compared peripheral oxygen saturation (SpO2) targets for critically ill children. The harm of interventions to raise SpO2 to > 94% may exceed their benefits.Methods: We undertook an open, parallel-group randomised trial of children > 38 weeks completed gestation and < 16 years of age receiving invasive or non-invasive respiratory support and supplemental oxygen who were admitted urgently to one of three paediatric intensive care units. A 'research without prior consent' approach was employed. Children were randomly assigned to a liberal oxygenation group (SpO2 targets > 94%) or a conservative oxygenation group (SpO2 = 88-92% inclusive). Outcomes were measures of feasibility: recruitment rate, protocol adherence and acceptability, between-group separation of SpO2 and safety. The Oxy-PICU trial was registered before recruitment: ClinicalTrials.gov identifier NCT03040570.Results: A total of 159 children met the inclusion criteria, of whom 119 (75%) were randomised between April and July 2017, representing a rate of 10 patients per month per site. The mean time to randomisation from first contact with an intensive care team was 1.9 (SD 2.2) h. Consent to continue in the study was obtained in 107 cases (90%); the children's parents/legal representatives were supportive of the consent process. The median (interquartile range, IQR) of time-weighted individual mean SpO2 was 94.9% (92.6-97.1) in the conservative oxygenation group and 97.5% (96.2-98.4) in the liberal group [difference 2.7%, 95% confidence interval (95% CI) 1.3-4.0%, p < 0.001]. Median (IQR) time-weighted individual mean FiO2 was 0.28 (0.24-0.37) in the conservative group and 0.37 (0.30-0.42) in the liberal group (difference 0.08, 95% CI 0.03-0.13, p < 0.001). There were no significant between-group differences in length of stay, duration of organ support or mortality. Two prespecified serious adverse events (cardiac arrests) occurred, both in the liberal oxygenation group.Conclusion: A definitive clinical trial of peripheral oxygen saturation targets is feasible in critically ill children. [ABSTRACT FROM AUTHOR]

A unique delay-dependent dynamic switching of optical nonlinearity in terms of saturation absorption (SA) and excited state absorption (ESA) in graphene oxide (GO) and reduced graphene oxide (RGO2 and RGO100) is achieved with an optical pump and white light super-continuum probe only above a threshold pump intensity. Infrared and chemical reduction are used to obtain RGO2 and RGO100 respectively. The switching regime of probe wavelength can be modulated by varying either pump wavelength or degree of reduction. When pumped at 415 nm, the threshold pump intensity to obtain switching property decreases to 9 GW/cm 2 for RGO2 from 18 GW/cm 2 in GO and the tunability range shifts from 471 to 526 nm for as grown GO to 519–623 nm in maximally reduced RGO2. Though the saturation intensity of intrinsic non-degenerate two photon absorption (nd-TPA) is found to be lower in GO (4.3 GW/cm 2 ) than RGO2 (18.2 GW/cm 2 ), nd-TPA coefficient increases from 0.0015 cm/GW (GO) to 0.0026 cm/GW (RGO2) with increasing reduction. The detailed kinetics of the scattering processes show variation as a function of pump power, probe wavelength and degree of reduction. A model band diagram based on amorphous-carbon model and a Tauc analysis are used to explain the unusual nonlinear optical properties. [ABSTRACT FROM AUTHOR]

This paper investigates the relative position and attitude tracking control of non-cooperative fly-around mission in the presence of parameter uncertainties, external disturbances, input saturation and full state constraints. Firstly, an integrated and coupled 6 DOF relative motion dynamic model is established, which is consisted of relative position model depicted in the line-of-sight (LOS) frame and relative attitude model described by Modified Rodriguez parameters (MRPs). Subsequently, by using the backstepping control method, an integrated robust adaptive anti-windup control scheme is proposed, in which uncertain parameters and unknown upper bound of the disturbances are estimated by adaptive technique, and the adverse effects caused by input saturation are reduced by the designed anti-windup compensator. To guarantee the full state constraints satisfied all the time, the barrier Lyapunov function method is incorporated into the backstepping control design. Rigorous stability proofs show that the designed robust adaptive controller guarantees that the relative motion states not only can be restricted in the prescribed constraint regions, but also can converge into the small regions with good robustness. Finally, numerical simulation results demonstrate the effectiveness and performance of the designed control scheme. [ABSTRACT FROM AUTHOR]

In this paper, we propose a novel approach to broadband model relative effective complex permittivity of soils (augmented broadband complex dielectric mixture model). The approach involves a combination of mixture equation and relaxation model. The mixture equation is an extension in frequency domain developed from a volume average approach. The relaxation model aims at integrating polarization effects that would occur over the frequency range under interest. In this framework, the relative effective complex permittivity is computed from a set of parameters including water saturation, porosity, cementation exponent, and relaxation parameters. The proposed model was tested and validated on a new set of data measured over the 1-MHz–3-GHz frequency range on compacted kaolin. The model was fit to the measured spectra with satisfactory agreement in terms of root-square-mean error. Furthermore, the comparison between estimated and experimentally measured water saturation and porosity has shown a good correlation. This indicates the great potential of this new model for monitoring state parameters for applications in geophysics and geotechnics. [ABSTRACT FROM AUTHOR]

In this study, Sendust alloy (Fe85Si9.6Al5.4) was fabricated by mechanical alloying process, and its crystal structure and magnetic properties were investigated. Sendust alloy has excellent soft magnetic properties and is widely used in different applications. Raw materials (Fe, Si, and Al) were milled by a planetary ball mill at different milling times, from 5 to 20 h. The resulted alloys were annealed at 1373 and 1473 K for 2 h, and the effect of annealing temperature was investigated on the magnetic properties. Crystal structure of the samples was investigated by X-ray diffractometery method. The results indicated that saturation magnetization of 10-h milled sample was at maximum, and it decreased both by increasing milling time and by annealing. These variations were discussed based on phase transformation from ordered to disordered phases and/or vice versa. The maximum saturation magnetization obtained, 156 emu/g, was comparable by those reported for Sendust alloy, which was prepared by other methods. Magnetization-temperature curves of the alloys and annealed ones were recorded by a Faraday balance. Two clear drops were observed on each M-T curve of the as-milled samples that displayed the existence of two different magnetic phases. On the other hand, there is just one drop on the M-T curves of the annealed samples, indicating that these samples were in a less disordered phase. [ABSTRACT FROM AUTHOR]