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The accreting millisecond X-ray pulsar IGR J17498−2921 went into X-ray outburst on 2023 April 13–15, for the first time since its discovery on 2011 August 11. Here, we report on the first follow-up NuSTAR observation of the source, performed on 2023 April 23, around 10 d after the peak of the outburst. The NuSTAR spectrum of the persistent emission (3–60 keV band) is well described by an absorbed blackbody with a temperature of |$kT_{\mathrm{ bb}}=1.61\pm 0.04$|  keV, most likely arising from the NS surface and a Comptonization component with power-law index |$\Gamma =1.79\pm 0.02$|⁠ , arising from a hot corona at |$kT_{e}=16\pm 2$| keV. The X-ray spectrum of the source shows robust reflection features which have not been observed before. We use a couple of self-consistent reflection models, relxill and relxillCp , to fit the reflection features. We find an upper limit to the inner disc radius of |$6\: R_{\mathrm{ ISCO}}$| and |$9\: R_{\mathrm{ ISCO}}$| from relxill and relxillCp model, respectively. The inclination of the system is estimated to be |$\simeq 40^{\circ }$| from both reflection models. Assuming magnetic truncation of the accretion disc, the upper limit of magnetic field strength at the pole of the NS is found to be |$B\lesssim 1.8\times 10^{8}$| G. Furthermore, the NuSTAR observation revealed two type-I X-ray bursts and the burst spectroscopy confirms the thermonuclear nature of the burst. The blackbody temperature reaches nearly 2.2 keV at the peak of the burst. [ABSTRACT FROM AUTHOR]

AbstractTotal reflection X-ray fluorescence spectrometry (TXRF) is a pivotal technique in modern atomic spectroscopy, distinguished by its capability for multi-element simultaneous determination, a wide dynamic concentration range, samples do not require acid digestion. Additionally, TXRF exhibits negligible matrix effects when samples are prepared as thin films. Based on these unique features, recent research efforts have increasingly employed laboratory-built TXRF systems for the determination of major and trace elements in various samples. Given the diverse and intricate nature of TXRF systems components, this paper provides an overview of critical components that constitute these systems, compares the influence of various parameters on analytical performance, and offers recommendations for component selection. Additionally, recent applications of laboratory-built TXRF in fields such as environmental monitoring, nuclear energy, and food safety are discussed, with a focus on sample preparation, analyzed elements, and quantitative analysis are presented together with analytical parameters such as detection limits and recoveries. By introducing the instrument components and their practical applications, this paper aims to guide researchers in the construction and optimization of TXRF systems, thereby promoting the advancement of TXRF in future research and practical applications. [ABSTRACT FROM AUTHOR]

AbstractIn order to investigate the elemental composition, a total of 19 potteries and two representative clay samples from Senjikothamangalam (Villupuram district) and 12 potteries and one representative clay sample from the Palayanur (Chengalpattu) archaeological sites in Tamil Nadu were analyzed using total reflection X-ray fluorescence spectroscopy. The presence of elements such as Fe, Ca, K, Ti, Al, Sr, Mn, P, V, Cr, Zn, Rb, Ni, Cu, Pb, Ga, Y, Bi, Br, and As were identified in the pottery and clay samples. Statistical analysis, such as Pearson correlation, cluster and principal component analysis were used to categorize the samples based on their elemental composition. The outcome of the Pearson correlation and cluster analysis corroborated that the Senjikothamangalam pottery samples (P-1 to P-19) were made using the same type of clay, except P-10. Similarly, all Palayanur pottery samples (P-20 to P-31) were manufactured from the same clay. The petrographic analysis of the potteries revealed further information about its provenance and making methods. [ABSTRACT FROM AUTHOR]

The black hole X-ray binary H1743−322 lies in a region of the Galaxy with high extinction, and therefore it has not been possible to make a dynamical mass measurement. In this paper, we make use of a recent model which uses the X-ray reflection spectrum to constrain the ratio of the black hole mass to the source distance. By folding in a reported distance measurement, we are able to estimate the mass of the black hole to be |$12\pm 2~\text{M}_\odot {}$| (⁠|$1\sigma$| credible interval). We are then able to revise a previous disc continuum fitting estimate of black hole spin |$a_*$| (previously relying on a population mass distribution) using our new mass constraint, finding |$a_*=0.47\pm 0.10$|⁠. This work is a proof of principle demonstration of the method, showing it can be used to find the mass of black holes in X-ray binaries. [ABSTRACT FROM AUTHOR]

One-stage synthesis technology for preparing carbon adsorbents with tailored porosity from agricultural waste is worthwhile due to their extensive application value. Thermal gravimetric analysis, low-temperature N2 adsorption, X-ray diffraction (XRD), small-angle X-ray scattering (SAXS), and Raman spectroscopy were used to record the structure transformations of carbon materials, namely pore development, proceeding in the course of the step-wise pyrolysis of renewable and low-cost raw materials such as walnut shells (WNSs), which was carried out within a temperature range of 240–950 °C in a CO2 flow. The minimum threshold carbonization temperature for preparing nanoporous carbon materials from WNSs, determined by the examination of the N2 adsorption data, was 500 °C. The maximum specific micropore volume and BET surface achieved in the process without holding a material at a specified temperature were only 0.19 cm3/g and 440 m2/g, respectively. The pyrolysis at 400–600 °C produced amorphous sp2 carbon. At a temperature as high as 750 °C, an increase in the X-ray reflection intensity indicated the ordering of graphite-like crystallites. At high burn-off degrees, the size of coherently scattering domains becomes smaller, and an increased background in X-ray patterns indicates the destruction of cellulose nanofibrils, the disordering of graphene stacks, and an increase in the amount of disordered carbon. At this stage, pores develop in the crystallites. They are tentatively assigned to crystallites with sizes of 15–20 nm and to micropores. According to the Raman spectra combined with the XRD and SAXS data, the structure of all the pyrolysis products is influenced by the complex structure of the walnut shell precursor, which comprises cellulose nanofibrils embedded in lignin. This structure was preserved in the initial stage of pyrolysis, and the graphitization of cellulose fibrils and lignin proceeds at different rates. Most of the pores accessible for gas molecules in the resulting carbon materials are associated with former cellulose fibrils. [ABSTRACT FROM AUTHOR]

We provided a comprehensive study of the properties of the black hole in the low-mass X-ray binary system 4U 1543-47, specifically focusing on the 2021 outburst (MJD 59380–59470). Using observations from the Insight - HXMT mission, we employed X-ray reflection fitting method and analysed spectral data to estimate key black hole parameters. Through our investigation redbased on 6 out of the 52 available observations, we estimated the spin parameter of the black hole to be |$0.902_{-0.053}^{+0.054}$| and the inclination angle of the accretion disc to be |$28.91_{-1.24}^{+1.82}$| ° (90 per cent confidence limits, statistical only), then we discussed the influence of high luminosity. Based on the relxill series models are not suitable for thick disc scenario, and in comparison with findings from other studies, we propose that our estimation of the spin value may be exaggerated. [ABSTRACT FROM AUTHOR]

The accuracy of determining arsenic and lead using the optical technique Slurry–Total Reflection X-ray Fluorescence (Slurry-TXRF) was significantly enhanced through the application of a machine learning method, aimed at improving the ecological risk assessment of agricultural soils. The overlapping of the arsenic Kα signal at 10.55 keV with the lead Lα signal at 10.54 keV due to the relatively low resolution of TXRF could compromise the determination of lead. However, by applying a Partial Least Squares (PLS) machine learning algorithm, we mitigated interference variations, resulting in improved selectivity and accuracy. Specifically, the average percentage error was reduced from 15.6% to 9.4% for arsenic (RMSEP improved from 5.6 mg kg−1 to 3.3 mg kg−1) and from 18.9% to 6.8% for lead (RMSEP improved from 12.3 mg kg−1 to 5.03 mg kg−1) compared to the previous univariable model. This enhanced predictive accuracy, within the set of samples concentration range, is attributable to the efficiency of the multivariate calibration first-order advantage in quantifying the presence of interferents. The evaluation of X-ray fluorescence emission signals for 26 different synthetic calibration mixtures confirmed these improvements, overcoming spectral interferences. Additionally, the application of these models enabled the quantification of arsenic and lead in soils from a viticultural subregion of Chile, facilitating the estimation of ecological risk indices in a fast and reliable manner. The results indicate that the contamination level of these soils with arsenic and lead ranges from moderate to considerable. [ABSTRACT FROM AUTHOR]

The wavelength‐dispersive X‐ray fluorescence (WDXRF) spectrometry was applied to determine Na, Mg, Al, P, S, K, Ca, Cr, Mn, Fe, Ni, Cu, Zn, Sr, Ba, and Pb concentrations in the needles of dwarfish spruce Picea canadensis conica and the blue prickly spruce Picea pungens glauca, as well in technogenic soil of Irkutsk city, in which these spruce species grow. All measurements were performed in vacuum using WDXRF spectrometer S8 TIGER produced by Bruker AXS, Germany. The calculated values of instrumental limit of detection (ILD) ranged from 0.5 for Ni to 67 mg/kg for Al for soil certified reference materials (CRMs) such as OOKO151 (light chestnut soil) and from 0.2 for Cu and Ni to 18–24 mg/kg for Na for the plant CRMs such as LB‐1 (birch leaf) and EC‐1 (Canadian waterweed). The repeatability is satisfactory. The values of relative standard deviations (RSDs) do not exceed 15% for soils and available plant material. With calculated T‐statistics, it was found that the WDXRF data do not contain systematic errors. The values of relative discrepancy for WDXRF, total reflection X‐ray fluorescence (TXRF) spectrometry, and atomic emission spectrometry with arc discharge (d.c. arc‐AES) results do not exceed 30% for studied elements. [ABSTRACT FROM AUTHOR]

Flexoelectric effect in ferroelectric epitaxy films has attracted significant attention due to its theoretical and application potentials. However, the origin and control of flexoelectric field is not yet fully understood. In this study, we investigated the surface structure of single-domain epitaxial BiFeO 3 films with a (111) orientation using grazing incidence X-ray diffraction and X-ray reflection methods. We observed large strain gradient on the surface of the BiFeO 3 films, which produces a giant flexoelectric field up to 82.55 MV/m at the surface of 15 nm thick BiFeO 3 film. Additionally, we discovered the presence of a surface layer with lower electron density than that of the underlying BiFeO 3 layer, which is related to the flexoelectric field. Moreover, with increased film thickness, we found the strain distribution along growth direction of the film is changed, thereby leads to the decreased flexoelectric field and increasing thickness of the surface layer respectively. These findings convinced the coupling between the strain state and surface structure, changing the thickness of the ferroelectric film and consequently the strain state is an efficient way to adjust the flexoelectric field and the surface structure. [ABSTRACT FROM AUTHOR]

Analytical calculations of absorption corrections for X‐ray powder diffraction experiments on non‐ideal samples with surface roughness, porosity or absorption contrasts from multiple phases require complex mathematical models to represent their material distribution. In a computational approach to this problem, a practicable ray‐tracing algorithm is formulated which is capable of simulating angle‐dependent absorption corrections in reflection geometry for any given rasterized sample model. Single or multiphase systems with arbitrary surface roughness, porosity and spatial distribution of the phases in any combination can be modeled on a voxel grid by assigning respective values to each voxel. The absorption corrections are calculated by tracing the attenuation of X‐rays along their individual paths via a modified shear‐warp algorithm. The algorithm is presented in detail and the results of simulated absorption corrections on samples with various surface modulations are discussed in the context of published experimental results. [ABSTRACT FROM AUTHOR]

The need for elemental analysis in quality control of food, pharmaceuticals and cosmetics, taking into account human safety, has become an essential requirement for any product destinated for commercialization and targets in particular potentially toxic elements. The main objective is to obtain reliable data on elemental content that enables end-users to make informed decisions and to address problems effectively. To align with the principles of green and sustainable analytical chemistry, recent efforts have focused on incorporating new, low-cost screening and quantitative analytical tools such as total reflection X-ray fluorescence spectrometry (TXRF). This paper provides an overview of recent TXRF applications in the elemental analysis of food, pharmaceuticals, and cosmetic samples. The state-of-the-art procedures for sample preparation with details on the sample type and amount, dilution steps, mixing agents, analysed elements, and addition of internal calibration standards are presented together with analytical parameters such as limits of detection and quantification. The current challenges for applying TXRF to each of these research fields are discussed. [ABSTRACT FROM AUTHOR]

Environmental pollution as a result of industrial activity is widespread in many urban areas including Chicago. In an effort to evaluate the heavy metal fraction originating from industrial activities, plant samples of Daucus Carota or wild carrot were collected at or adjacent to six sites located in two of Chicago's designated industrial corridors. Plants, especially herbaceous species, have been deemed suitable as environmental pollution monitors as they are able to provide information about the heavy metal fraction accessible to biota. The leaves of Daucus Carota were acid digested and analyzed with total reflection X‐ray fluorescence spectrometry TXRF. The results showed elevated heavy metal mass fractions for at least one collection site which is close to an operational railyard. Other studies investigating heavy metals in proximity to railroad operations found elevated mass fractions for several elements, but specifically manganese as well. This suggests that abrasion from shunting and breaking releases certain pollutants into the local environment. The data were compared with studies executed in Rome, Italy, and Pakistan, which used Daucus Carota to evaluate heavy metal pollution. It was found that the heavy metal mass fractions obtained for Chicago were higher for some elements indicating an increased pollutant burden for these elements. The same samples were also analyzed by graphite furnace atomic absorption spectrometry GFAAS for the elements copper and lead and the data compared. Those two elements were chosen as they were present at each location and GFAAS has proven to be highly sensitive for them. It was found that the two methods provided comparable results for copper, whereas for lead, TXRF overestimated the mass fractions most likely due to limitations of the spectra evaluation software. The analysis of a certified reference material ‘BCR 679 white cabbage’ showed that most data obtained by TXRF were in good agreement with the certified values, with the exception of lead, which was not certified. However, since GFAAS has high sensitivity toward lead and is considered reference method for that element by regulatory agencies, a comparison between GFAAS and TXRF data for lead in the same sample can serve as good indicator for TXRF performance. [ABSTRACT FROM AUTHOR]

To sensitively determine 99Tc, a new method for internal quantification of its most common and stable species, [99Tc]Tc O 4 - , was developed. Anion-exchange chromatography (IC) was coupled to inductively coupled plasma–mass spectrometry (ICP-MS) and equipped with an aerosol desolvation system to provide enhanced detection power. Due to a lack of commercial Tc standards, an isotope dilution-like approach using a Ru spike and called isobaric dilution analysis (IBDA) was used for internal quantification of 99Tc. This approach required knowledge of the sensitivities of 99Ru and 99Tc in ICP-MS. The latter was determined using an in-house prepared standard manufactured from decayed medical 99mTc-generator eluates. This standard was cleaned and preconcentrated using extraction chromatography with TEVA resin and quantified via total reflection X-ray fluorescence (TXRF) analysis. IC coupled to ICP-MS enabled to separate, detect and quantify [99Tc]Tc O 4 - as most stable Tc species in complex environments, which was demonstrated in a proof of concept. We quantified this species in untreated and undiluted raw urine collected from a patient, who previously underwent scintigraphy with a 99mTc-tracer, and determined a concentration of 19.6 ± 0.5 ng L−1. The developed method has a high utility to characterize a range of Tc-based radiopharmaceuticals, to determine concentrations, purity, and degradation products in complex samples without the need to assess activity parameters of 99(m)Tc. [ABSTRACT FROM AUTHOR]

The main purpose of this study was the comparison of the results of quantification obtained via different sample preparation approaches such as microwave‐assisted wet digestion (MAWD) and suspension preparation. Two total reflection x‐ray fluorescence (TXRF) spectrometers equipped with Mo x‐ray tubes were used to compare results obtained via two different paths of sample preparations which would further be compared to the conventional way of analysis by inductively coupled plasma optical emission spectrometry (ICP‐OES) including MAWD. Three dietary supplement samples with different sets and concentrations of elements were analyzed. The benefits and limitations of the simplified path of sample preparation were highlighted. A round‐robin test between TXRF and ICP‐OES was discussed. Accuracy as the percentage of recovery in all measurements ranged from 80 to 120. Precision for all results did not exceed 8% for TXRF and 5% for ICP‐OES. Limits of quantification by TXRF are ranged from 1 to 0.01 mg/pill for different elements. It was shown that suspension preparation of samples might be a useful response to increasing demand for quality control of dietary supplements since it is less time consuming and cost efficient. [ABSTRACT FROM AUTHOR]

Waipouaite, Ca3 (V 4.5 4 + V 0.5 5 + ) O9[(Si2O5(OH)2][Si3O7.5(OH)1.5]·11H2O, is a new mineral from the Aranga Quarry, Northland Region, New Zealand. It occurs in basalt as overgrowths on thompsonite-Ca and chabazite-Ca and as inclusions within calcite and okenite. It forms dark olive green to almost black prismatic crystals to 0.3 mm in length. Crystals are transparent to translucent with a vitreous luster. The Mohs hardness is ~2, and the measured density is 2.24(2) g/cm3. The new mineral is biaxial (+), with α = 1.620(5), β = 1.622(5), γ = 1.628(5) (white light). The calculated 2V is 60.2°. Dispersion could not be observed. The optical orientation is Z = b. Pleochroism is X blue-green, Y olive green, Z olive; X > Y >> Z. Electron microprobe analyses gave the empirical formula (based on 36 O apfu) (Ca2.90Na0.05K0.04Sr0.01)Σ3.00 (V 4.60 4 + V 0.44 5 + ) Σ 5.04 (Si4.97Al0.02)Σ4.99O21.45OH3.55·H2O11.00. Waipouaite is monoclinic, P21/c, a = 12.843(3), b = 23.589(5), c = 11.560(2) Å, β = 115.54(3)°, V = 3160.0(13) Å3, and Z = 4. The eight strongest reflections in the X-ray powder diffraction pattern are [dobs in Å (I) (hkl)]: 11.78 (100) (020, 100), 9.54 (16) (011), 7.85 (19) (021), 6.29 (32) (031), 5.92 (31) (040), 5.22 (21) (1 22), 3.140 (18) (3 33), 2.850 (17) (180, 242). The crystal structure was refined using synchrotron single-crystal X-ray data to R1 = 6.85% for 6594 reflections with I>2σI. Waipouaite is the first natural polyoxovanadosilicate and has a novel structure based on [(V4+,V5+)5OI7] polyoxovanadate units, which are unique in natural and synthetic phases. Synthesis of polyoxovanadosilicates has proved to be a great challenge, and the discovery of waipouaite demonstrates that these compounds can form under natural conditions. [ABSTRACT FROM AUTHOR]

Natromelansonite, Na3Zr[Si7AlO19]⋅4–5H2O, was found at the Poudrette (Demix) quarry, Mont Saint-Hilaire, Quebec, Canada in a highly altered pegmatite together with a clay mineral, steacyite, polylithionite and rhodochrosite. It occurs as an outer zone of tabular crystals to 0.1 × 0.3 × 1 mm in size flattened on (001). The inner zone is made of melansonite. The mineral is grey with white powder colour and vitreous lustre. The cleavage is parallel to {010}, perfect. The Mohs hardness is 3.5. The mineral has green fluorescence under short-wave ultraviolet light. The D calc is 2.31 g/cm3. The infrared spectrum is reported. The composition (wt.%, average of 8 analyses) is Na2O 10.08, K2O 1.72, CaO 0.24, BaO 0.32, MnO 0.10, Al2O3 6.86, Y2O3 0.35, Yb2O3 0.55, SiO2 56.23, ZrO2 14.78, H2O 9.52, total 100.75. The empirical formula calculated on the basis of O = 23 apfu and H = 8 apfu is Na(□Na0.38Ca0.02Mn0.01)2(Na0.70K0.28Ba0.02)Σ1.00(Zr0.91Y0.02Yb0.02)Σ0.95(Si7.08Al1.02)Σ8.10O19⋅4H2O. The mineral is monoclinic, P 21 /m , a = 6.5156(3) Å, b = 24.061(1) Å, c = 6.9759(6) Å, β = 90.453(5)° and V = 1093.61(9) Å3 and Z = 2. The strongest reflections of the powder X-ray diffraction pattern [ d ,Å(I)(hkl)] are: 12.02(100)(020), 6.97(89)(001), 6.51(39)(100), 3.416(37)(160), 3.062(42)($\bar{1}$ 61, 102, 161 and $\bar{1}$ 12), 3.018(38)(230 and 042), 2.864(40)(240 and 132). The crystal structure, solved and refined from single-crystal X-ray diffraction data (R 1 = 0.042), is based on a double sheet of tetrahedra (T) and a sheet of octahedra (O) that alternate along the [010] direction forming a TOT structure typical for members of the rhodesite mero-plesiotype series. [ABSTRACT FROM AUTHOR]

A new cascade impactor has been developed with the arrangement of the classifying nozzles optimized for analysis of the collected particles by total reflection X-ray fluorescence (TXRF). TXRF offers detection limits in the range of a few picograms of absolute mass and therefore poses great potential for the elemental analysis of heavy metals in aerosol particles. To fully exploit this high sensitivity, particles have to be collected in the effective analysis area of the TXRF instrument, which is often smaller than typical deposition patterns of commercial impactors or filter samplers. This is achieved by a novel compact arrangement of the classifying nozzles within a circular area of a diameter of less than 5 mm. A decreasing density of the nozzle spacing from the inside to the outside of the nozzle cluster allows for constant cross-flow conditions, minimizing the mutual influence of the individual nozzles. The design of a multistage cascade impactor is presented to individually sample PM10 , PM2.5 and PM1 size fractions. Considering the high sensitivity of TXRF analysis, constructive measures have been taken to prevent attrition of impactor material which might lead to methodical blank values. Experimental validation confirms that neither attrition nor cross-contamination can be observed. Furthermore, a new spin-coating method has been developed which makes it possible to apply a thin and defined adhesive layer of grease to the sample carrier with good repeatability. Application of the impactor in a case study at an urban site at Potsdamer Platz, Berlin, Germany, shows that sampling at a moderate volume flow rate of 5 Lmin-1 , the particle mass collected in 30 min or less is sufficient for reliable TXRF analysis of heavy metal concentrations (Fe , Zn , Cu , Mn , Pb and Ni) in ambient aerosol. This high time resolution enables snapshot sampling, e.g. to quantify variations in particle source strengths. Overall, the new impactor optimized for TXRF analysis bears great potential to improve the quantification of particulate trace metals and other elements in PM10 , PM2.5 and PM1 with high time resolution. [ABSTRACT FROM AUTHOR]

Photon interaction parameters can also reveal the development of cancer in breast tissues at various ages. In the present investigations, the MAC values were estimated using EpiXs software for normal and malignant human breast tissues at different age groups by incorporating experimentally determined trace elements by TXRF (Total reflection x-ray fluorescence) spectrometer. A significant difference in the values of effective atomic number was observed between normal and malignant breast tissues of different age groups. As the present investigations incorporate measured trace elements in EpiXs code, the authors feel that the parameters are more authentic, useful to radiation diagnostics, and therapeutic. [ABSTRACT FROM AUTHOR]

The new mckelveyite group mineral, alicewilsonite-(YLa), Na 2 Sr 2 YLa(CO 3) 6 ⋅ 3H 2 O, was found together with kamphaugite-(Y), paratooite-(Y), bastnäsite-(La), and decrespignyite-(Y) coating along fractures in dolomite at the Paratoo copper mine, South Australia, Australia. It occurs as pale pink to colourless pseudohexagonal tabular crystals up to 150 µ m in size. The streak is white; the lustre is vitreous. The mineral has no cleavage. Dcalc is 3.37 g cm -3. Alicewilsonite-(YLa) is optically biaxial (-), α = 1.556(2), β= 1.582(2), γ= 1.592(2), 2V (meas.) = 60(2)°, 2V (calc.) = 63° (589 nm). The IR spectrum is reported. The composition (wt %, average of seven analyses) is Na 2 O 7.43, CaO 2.00, SrO 18.43, BaO 1.64, Y 2 O 3 9.59, La 2 O 3 11.74, Pr 2 O 3 1.29, Nd 2 O 3 5.74, Sm 2 O 3 0.44, Eu 2 O 3 0.09, Gd 2 O 3 0.95, Dy 2 O 3 1.15, Ho 2 O 3 0.25, Er 2 O 3 0.89, Yb 2 O 3 0.29, CO 2 29.78, H 2 O 6.18, total 97.88. The empirical formula calculated on the basis of six cations with 3 H 2 O molecules is as follows: Na 2.10 Ca 0.31 Sr 1.56 Ba 0.10 Y 0.74 La 0.63 Pr 0.07 Nd 0.30 Sm 0.03 Eu 0.01 Gd 0.04 Dy 0.05 Ho 0.01 Er 0.04 Yb 0.01 (CO 3) 5.92 (H 2 O) 3. The mineral is triclinic, P 1, a= 8.9839(2), b= 8.9728(3), c= 6.7441(2) Å, α= 102.812(2)°, β= 116.424(2)°, γ= 60.128(2)°, and V= 422.17(2) Å 3 and Z= 1. The strongest reflections of the powder X-ray diffraction pattern [ d ,Å(I)(hkl)] are 6.03(43)(001), 4.355(100)(1 1‾ 0, 2‾1‾ 1, 120), 4.020(30)(1‾ 11, 210, 1‾2‾ 1), 3.188(29)(2‾1‾ 2, 1 1‾ 1, 121), 2.819(96)(002, 1‾ 12, 211, 1‾2‾ 2), 2.592(40)(3‾ 01, 030, 3‾3‾ 1), 2.228(33)(2‾ 21, 4‾2‾ 1, 2‾4‾ 1). 2.011(36)(2‾ 22, 003, 420, 2‾4‾ 2), 1.9671(32)(3‾ 03, 301, 0 3‾ 2, 032, 3‾3‾ 3, 331). The crystal structure was solved and refined from single-crystal X-ray diffraction data (R1= 0.058). [ABSTRACT FROM AUTHOR]

The power conversion efficiency (PCE) of perovskite solar cells (PSCs) has significantly improved through advancements in fabrication methods, which have primarily focused on the perovskite absorber layer. The significance of improving the charge transport layer as the next crucial step toward achieving highly stable and efficient PSCs has also been emphasized. In inverted PSCs (i‐PSCs), the selection of a suitable p‐type hole‐transporting layer (HTL) has been restricted to mainly organic materials due to the rarity of p‐type inorganics. The instability and inherent disadvantages of organics necessitate the use of stable p‐type oxides as HTLs for i‐PSCs. Herein, uniform, conformal, and practical, yet thermal atomic layer deposition (ALD) for NiO is demonstrated by employing two different oxidant, ozone (O3) and hydrogen peroxide (H2O2). Both ALD‐NiO films are characterized by X‐ray diffraction and X‐ray reflection. By conducting X‐ray photoelectron spectroscopy analysis of the ALD‐NiO surfaces, a correlation between the oxidation power of the oxidant during ALD and the surface oxidation state of the ALD‐NiO films is established. Finally, the relationship between the oxidation state of the surfaces with different oxidant and the i‐PSC performance is verified. The fabricated i‐PSCs exhibit a PCE exceeding 19%. [ABSTRACT FROM AUTHOR]

The development of techniques to measure accurately black hole spins is crucial to study the physics and astrophysics of these objects. X-ray reflection spectroscopy is currently the most popular method to estimate the spins of accreting black holes; so far it has provided a spin measurement of about 40 stellar-mass black holes in X-ray binaries and 40 supermassive black holes in active galactic nuclei. The relativistic precession model (RPM) is another method to measure the spins of stellar-mass black holes: it requires the measurement of the frequencies of three simultaneous quasi-periodic oscillations and can potentially provide precise estimates of the black hole mass and spin. However, the two methods do not seem to provide consistent results when applied to the same sources, which questions the reliability and accuracy of these measurements. Recently, the RPM has been applied to infer the spin of the black hole in XTE J1859+226. The authors found a * = 0.149 ± 0.005 (68  per cent CL). There are no other spin measurements of this source. We looked for archived RXTE observations of XTE J1859+226 with blurred reflection features and found 23 spectra suitable for measuring the spin. We employed two different models with relxill and relxillD and obtained a higher spin value from all these fits. From simultaneous fitting of seven spectra of higher quality, we found |$a_* = 0.986^{+0.001}_{-0.004}$| and a * = 0.987 ± 0.003 (90  per cent CL, statistical) with relxill and relxillD , respectively. Our results confirm the discrepancy between the spin measurements inferred from the two techniques. [ABSTRACT FROM AUTHOR]

In the presented study, X-ray photoelectron spectroscopy and total reflection X-ray photoelectron spectroscopy methods were applied to analyze the Ti (75 nm) and Pd (100 nm) nanolayers deposited on the Si substrate using magnetron sputtering. The aim of the research was to determine the elemental composition and surface homogeneity of the analyzed nanolayers before their irradiation with highly charged xenon ions and to estimate the detection limit of the X-ray photoelectron spectroscopy technique for various glancing angles. The measurements were conducted using the SPECS mono-XPS system in the Institute of Physics at the Jan Kochanowski University (Kielce, Poland). The experimental setup and measurement conditions for the studied Ti and Pd layers are described. The X-ray photoelectron spectroscopy spectra were registered both for the non-total (35° and 10° angles) and total reflection (2:2° for the Pd nanolayer and 1:5° for the Ti nanolayer) regimes. The position of the C 1s photoelectron peak was applied (C-C component, binding energy 284.8 eV) to calibrate energy. First, the homogeneity of the nanolayers was investigated. The analysis of spectra concentrated on investigating the photoelectron peaks and, consequently, on determining the following: the binding energy of electrons, the intensity and full width at half maximum of photoelectron peaks, the background level, and the elemental composition of the nanolayer surface. In this study, the detection limit of the X-ray photoelectron spectroscopy measurements for different photoelectron peaks was calculated in relation to the excitation angle. An improvement of the X-ray photoelectron spectroscopy detection limit by a factor of 3-6, depending on the type of photoelectron peak, was observed for the angles below the critical angle of the X-ray total reflection phenomenon. [ABSTRACT FROM AUTHOR]

The increasing worldwide use of different kinds of clothes with ultraviolet protection in recent years, in particular employing titanium dioxide nanoparticles, is driving the researchers' attention to the possible environmental problems due to titanium release. This study aims at determining the amount of titanium released from seven ultraviolet-protective garments into the wash water employing total reflection X-ray fluorescence spectrometry. For this, a wash protocol was designed based on the international standard ISO 105-C06:2010 and the literature. Pieces (4 cm × 10 cm) of textile were sampled from the garments and submitted 30 times to the wash protocol. The wash water produced in each wash was then prepared for total reflection X-ray fluorescence analysis. Results showed that the titanium released in 30 washes was between 8.6 ± 1.3 µg/L and 168 ± 3 µg/L. Every sample released titanium in the first to third wash, except sample 1, which first released titanium in the 18th wash. The greatest titanium release in one single wash was also the 18th wash of sample 1, which released 77 ± 2 µg/L. These results showed the good performance of total reflection X-ray fluorescence spectrometry in quantifying low titanium amounts in wash water, which is a hard task even for well-established analytical methods. [ABSTRACT FROM AUTHOR]

M n 2 Au is a bimetallic antiferromagnetic with an extraordinarily high Néel temperature of 1600 K. M n 2 Au has also been found to demonstrate Néel-order spin–orbit torque, allowing for electrical switching of the antiferromagnetic Néel vector. This has led to much interest in this material for spintronic applications. Here, we detail the growth of high quality M n 2 Au (110) thin films. The films were grown on a high quality Pt (111) buffer layer, which was grown on an A l 2 O 3 (0001) substrate. The M n 2 Au films have excellent crystalline quality as demonstrated by x-ray diffraction, x-ray reflection, and reflection high energy electron diffraction measurements. The M n 2 Au (110) films are found to grow with three equivalent in-plane rotation domains, caused by the Pt/ A l 2 O 3 substrate. [ABSTRACT FROM AUTHOR]

We present the results from the spectral and timing analysis of the accreting neutron star (NS) 1A 1744−361 from the Nuclear Spectroscopic Telescope ARray observation performed in its 2022 outbursts. The unabsorbed bolometric X-ray luminosity during this observation in the energy band 0.1–100 keV is 3.9 × 1037 erg s−1, assuming a distance of 9 kpc. During this observation, the source was in the banana branch of the atoll track. The source spectrum exhibits relativistic disc reflection and clear absorption features when an absorbed blackbody and cut-off power-law model describes the continuum emission. The 3–50 keV source spectrum is well fitted using a model combination consisting of an absorbed single-temperature blackbody and a reflection model along with the addition of a warm absorber component. The inner-disc radius, R in, obtained from the reflection fit is ∼(1.61–2.86) R ISCO = (8.4–14.9) R g (17.6–31.2 km for a 1.4 M⊙ NS). This measurement allowed us to further constrain the magnetic field strength to B ≲ 0.94 × 109 G. The strong absorption features ∼6.91 keV and ∼7.99 keV imply the presence of highly ionized absorbing material with a column density N H of ∼3 × 1022 cm−2, emanating from the accretion disc in the form of disc wind with an outflow velocity of v out ≃ 0.021 c ≃ 6300 km s−1. [ABSTRACT FROM AUTHOR]

Glioblastoma (GBM) is a fast-growing and aggressive brain tumor which invades the nearby brain tissue but generally does not spread to the distant organs. Nonetheless, if untreated, GBM can result in patient death in time even less than few months from the diagnosis. The influence of the tumor progress on organs other than brain is obvious but still not well described. Therefore, we examined the elemental abnormalities appearing in selected body organs (kidney, heart, spleen, lung) in two rat models of GBM. The animals used for the study were subjected to the implantation of human GBM cell lines (U87MG and T98G) characterized by different levels of invasiveness. The elemental analysis of digested organ samples was carried out using the total reflection X-ray fluorescence (TXRF) method, independently, in three European laboratories utilizing various commercially available TXRF spectrometers. The comparison of the data obtained for animals subjected to T98G and U87MG cells implantation showed a number of elemental anomalies in the examined organs. What is more, the abnormalities were found for rats even if neoplastic tumor did not develop in their brains. The most of alterations for both experimental groups were noted in the spleen and lungs, with the direction of the found element changes in these organs being the opposite. The observed disorders of element homeostasis may result from many processes occurring in the animal body as a result of implantation of cancer cells or the development of GBM, including inflammation, anemia of chronic disease or changes in iron metabolism. Tumor induced changes in organ elemental composition detected in cooperating laboratories were usually in a good agreement. In case of elements with higher atomic numbers (Fe, Cu, Zn and Se), 88% of the results were classified as fully compliant. Some discrepancies between the laboratories were found for lighter elements (P, S, K and Ca). However, also in this case, the obtained results fulfilled the requirements of full (the results from three laboratories were in agreement) or partial agreement (the results from two laboratories were in agreement). [ABSTRACT FROM AUTHOR]

The Total reflection X-ray Fluorescence technique is increasingly popular for its simplicity and rapid elemental screening. This study evaluates the various analytical parameters including spectroscopic resolution, absolute sensitivity, relative element sensitivity, lowest limits of detection, accuracy and precision of the Total reflection X-ray Fluorescence spectrometer. This evaluation is conducted using quartz and acrylic sample carriers with mono and multi-element standards. Notably, the quartz sample carrier demonstrated excellent values of spectroscopic resolution, absolute sensitivity, the lowest limits of detection, a recovery rate of 90–110% and a coefficient of variation of 3–6% for the quantified elements from mono and multi-element standards. These findings underscore the robust analytical capability of the Total reflection X-ray Fluorescence technique for multi-trace elemental analysis. This research article not only provides practical and straightforward guidelines for handling Total reflection X-ray Fluorescence spectrometer but also confirms the practicality and effectiveness of the sample carriers for rapid and reliable elemental screening applications. [ABSTRACT FROM AUTHOR]

Total reflection X-ray fluorescence (TXRF) analysis is used to determine the concentrations of trace elements in liquid samples. Solutions are generally added dropwise onto a flat substrate and dried. When liquids with low elemental levels are analyzed, a hydrophobic substrate is employed to prepare a small dome-shaped residue. In the analyses of high-level solutions (high elemental concentration solution), the quantitative accuracy and measurement sensitivity deteriorate because X-ray fluorescence (XRF) is absorbed inside the thick residue. By preparing a thin residue, it is possible to reduce this absorption effect. In our previous study, atmospheric pressure plasma jet (APPJ) treatment was used to prepare a superhydrophilic substrate. The time that super-hydrophilicity is maintained is not yet known and determining this value is important for performing TXRF analysis. Therefore, we measured the contact angles of the droplets and performed X-ray photoelectron spectroscopy of the substrate surfaces to determine the relationships between the experimental values and the elapsed time. The optimal APPJ-treated area has not yet been determined and is one of the most important factors for high-sensitivity analysis. In this study, we controlled the APPJ-treated area by preparing four polytetrafluoroethylene (PTFE) masks with different hole diameters and obtained recoveries, relative standard deviations, and minimum detection limits (MDLs) to identify the optimal APPJ-treated area. A PTFE mask with a diameter of 4 mm generated the best values, particularly for low-Z elements. By controlling the diameter of the dried residue to 4 mm, the MDL value in aluminum was improved by a factor of 1.7. [ABSTRACT FROM AUTHOR]

Between 1924 and 1947, Gino Severini decorated five churches in the Romand region of Switzerland with monumental religious wall paintings. This mural art played an important role in the Italian artist's career despite being mostly unknown and not easily found. The painting methods and materials of these modern Swiss murals were characterized by combining historical and archival research with onsite visual and scientific examination. Most pigments were identified with noninvasive methods integrating mapping techniques (i.e., technical photography and digital microscopy) with point analysis (x‐ray fluorescence and reflection FT‐IR spectroscopy). The results of these portable techniques were completed with SEM‐EDS, μFT‐IR FPA imaging, and μRaman analyses on micro‐samples which provided stratigraphic and compositional information to complement the noninvasive results. Overall, the data obtained show that Severini used both traditional pigments (e.g., Sangiovanni white and ochres/earths of various color) and modern ones, such as cadmium‐based pigments, with different painting techniques (e.g., zinc white was applied exclusively a secco). Apart from cerulean blue (cobalt stannate) and Naples yellow (lead antimonate) found only in two locations, the same set of pigments was documented in all of Severini's Swiss murals. The characterization of the artist's palette is important to understand the technical painting process followed by Severini, his interest on new painting materials available on the market and, at the same time, loyalty towards traditional painting methods, such as painting a fresco. [ABSTRACT FROM AUTHOR]

An approach to TXRF determination of the composition of perovskite nanocomposites of the putative compositions CsPbBr2Cl and CsPbBr2I is proposed. Sample preparation consists in the treatment of hydrophobic samples with dimethylformamide (DMFA) and the subsequent dilution of the obtained solutions with water. When using a copper solution as an internal standard, the reproducibility of the results of TXRF determination of the elements is attained with Sr no more than 0.05. The validity of the determination of Cs, Pb, Br, and I is confirmed by the results of their determination by ICP-MS in solutions after processing samples in DMFA followed by dilution with 2% HNO3 for Cs, Pb, and Br or tetramethylammonium hydroxide (TMAH) for Cs, Pb, Br, and I, whereas the determination of chlorides is confirmed by the method of direct potentiometry in diluted solutions. It is shown that lead does not form insoluble chlorides in the TMAH solution and does not interfere with the determination. The effect of bromides on the determination of chlorides is characterized by a potentiometric coefficient of 10–3. The results obtained provide the determination of the stoichiometry of the synthesized compounds CsPbBr2Cl and CsPbBr2.7I0.3. [ABSTRACT FROM AUTHOR]

The development of chemical sensors is relevant for solving environmental problems of monitoring the atmosphere of cities and industrial zones. Semiconductor sensors based on metal oxides are promising chemical gas sensors owing to their high sensitivity, low cost, small size, and low energy consumption. The first attempts at pilot operation of atmospheric air monitoring systems based on such sensors revealed insufficient response stability. Doping of the basic material with silicon can solve the problem. At the same time, data on the amount and distribution of the dopant in the material are necessary to determine the relationship "synthesis conditions–composition–properties." We propose an approach to the determination of the composition of novel semiconductor materials based on β-Ga2O3 with a silicon dopant content from 0.5 to 2 at %. The approach included grinding of samples using a planetary mill and preparation of suspensions in ethylene glycol, followed by TXRF determination of the analytes on sapphire substrates using the method of absolute contents (Si) with Sr of 0.08 and the method of external standard (Ga) with Sr of 0.04. X-ray fluorescence analysis of the samples was performed using an S2 PICOFOX spectrometer (Bruker Nano GmbH, Germany). MoKα radiation was used to excite X-ray fluorescence. The spectrum acquisition time was 250 s. It is shown that the homogeneity of the dopant distribution in the material can be estimated using the analysis of the suspensions. The studied materials demonstrate an irreproducible sensory response which we associate with the revealed inhomogeneity of the silicon distribution over the surface of β-Ga2O3. [ABSTRACT FROM AUTHOR]

We report the results of fitting Insight-HXMT data to the black hole X-ray binary MAXI J1348-430, which was discovered on January 26th, 2019, We also inferred the ionization state and iron abundancewith the Gas Slit Camera on-board MAXI. Several observations at the beginning of the first burst were selected, with a total of 10 spectra. From the residuals of fits using disc plus power-law models, X-ray reflection signatures were clearly visible in some of these observations. We use the state-of-the-art |$\tt {relxill}$| series reflection model to fit six spectra with distinct reflection signatures and a joint fit to these spectra. In particular, we focus on the results for the black hole spin values. Assuming R in = R ISCO, the spin parameter is constrained to be |$0.82^{+0.04}_{-0.03}$| with 90 per cent confidence level (statistical only). [ABSTRACT FROM AUTHOR]

Purpose: Transmission‐target x‐ray tubes generate more x‐rays than reflection thick‐target x‐ray tubes. A transmission x‐ray tube combined with radiosensitizers has a better radiation enhancement effect. This study investigated the feasibility of using a transmission x‐ray tube with radiosensitizers in clinical radiotherapy and its effect on radiation dose enhancement. Methods: This study used MCNP6.2 to simulate the model of a transmission x‐ray tube and Co‐60 beam. The radiation enhancement effect of radiosensitizers was examined with iodine‐127 (I‐127), radioiodinated iododeoxyuridine (IUdR), and gold nanoparticles (GNPs). Results: The study results showed that the dose enhancement factor (DEF) of the transmission x‐ray tube with GNPs was 10.27, which was higher than that of I‐127 (6.46) and IUdR (3.08). The DEF of the Co‐60 beam with GNPs, I‐127, and IUdR was 1.23, 1.19, and 1.2, respectively. The Auger electron flux of the transmission x‐ray tube with GNPs was 1.19E+05 particles/cm2. Conclusions: This study found that a transmission x‐ray tube with appropriate radiosensitizers could produce a high rate of Auger electrons to fulfill the radiation enhancement effect, and this procedure has the potential to become a radiotherapy modality. [ABSTRACT FROM AUTHOR]

Major and trace elements in polymetallic minerals are crucial subjects of study in ore geology. However, efficient and convenient methods have yet to be developed for processing high-density and hydrophobic sulfide ores, like copper–nickel sulfide ore, which is a strategic metal resource. In this paper, a novel method for the multielement analysis of copper-nickel sulfide ore using total reflection X-ray fluorescence spectrometry (TXRF) combined with slurry sampling was developed. This approach is based on the preparation of a suspension in a liquid at a certain viscosity without sample digestion. The effects of the sample amount and particle size on the analysis results were evaluated. The method validation was achieved through these processes: comparison with inductively coupled plasma atomic emission spectrometry (ICP-AES) results; analysis of certified reference materials, including copper-nickel cobalt ore and cobalt-rich nodule. The dispersants of ethylene glycol and 1% Triton X-100 applied in sulfide ore were also evaluated. For most elements, the relative error and relative standard deviation were under 10% in ethylene glycol. By contrast, suspensions with 1% Triton X-100 showed poorer reproducibility, particluarly in samples with sulfide-rich content, requiring further enhancement. For high-specific gravity sulfide ores, a dispersant of ethylene glycol is recommended to enhance the result of accuracy and reproducibility. [ABSTRACT FROM AUTHOR]

The data of X-ray diffraction and IR spectroscopy of synthetic aluminosilicates of the kaolinite subgroup with different degrees of crystallinity are analyzed. The samples are obtained under hydrothermal conditions in alkaline and neutral media with different durations of synthesis. It is shown that as the synthesis time increases a gradual transition of the amorphous phase to the crystalline phase is observed, which is reflected in the IR spectra by the shift of the bands related to the oscillations of the groups in the octahedral and tetrahedral grids. The first band of stretching vibrations of hydroxyl groups at 3628 cm–1 appears after three days of hydrothermal treatment in a neutral medium, and under alkaline conditions with the same duration of treatment, two more bands are observed at 3687 and 3668 cm–1. The detected changes in the IR spectra correspond to the appearance of the characteristic X-ray reflections of halloysite according to the XRD data. Thus, IR spectroscopy can be considered as a method for a qualitative assessment of the degree of crystallinity. [ABSTRACT FROM AUTHOR]

Atomic layer deposition (ALD) of multicomponent materials is challenging because the growth characteristics often deviate from what is expected due to the difference in surface characteristics of heterogeneous and single materials, resulting in undesired thickness or properties. For metal oxides, the growth characteristics highly rely on the surface hydroxyl groups, which play a role as the reactive site. Thus, studying the reaction mechanism of a precursor on hydroxyl-terminated heterogeneous surfaces is important for understanding the nonideal growth of ternary oxide. Here, we investigated the correlation between hydroxyl and the growth of ALD TiSiOx depending on temperature, analyzing infrared spectra, and chemical compositions. The results show that large amounts of hydroxyl are detected in TiSiOx deposited at 100 °C, where the adsorption of H2O on Ti–O–Si bonds is favorable. It leads to higher growth per cycle (GPC) than the estimated value. In contrast, the hydroxyl disappears at 200 °C due to dehydroxylation, resulting in lower GPC. Differences in hydroxyl also influence the film density as revealed in x-ray reflection spectra, which is related to the film qualities (e.g., elastic modulus and dry etch rates). This work provides insight into how to control hydroxyl in the ALD of ternary oxides, which is susceptible to hydroxyl incorporation, leading to undesired growth characteristics. [ABSTRACT FROM AUTHOR]

This review covers characteristics and potential applications of various versions of the X-ray fluorescence (XRF) spectrometry for analyzing both liquid and solid samples. Particular emphasis is given to research published within the past decade, as information on XRF's previous applications can be found in earlier reviews and monographs. The results of experiments on determining fundamental atomic parameters, such as mass absorption coefficients, fluorescence yields, transition probabilities for the emission of specific lines of elements, and nonradiative transition probabilities. Additionally, the review addresses the capabilities of newly designed models of XRF spectrometers developed in recent years. The application of total reflection X-ray fluorescence spectrometry for diverse samples is examined in greater detail. Furthermore, the document presents data on the utilization of XRF in investigating nanoparticles of some typical materials. These particles exhibit qualitatively novel properties and have become a focal point of nanotechnology, an area rapidly developing in the last few decades. [ABSTRACT FROM AUTHOR]

Atmospheric particulate matter (PM) is considered to be a set of pollutants suspended in the air, from industrial processes, motor vehicle exhaust, resuspended street dust, biomass burning, and others. Among the toxic chemical compounds, PM is considered contaminants of great importance for researchers, as they offer harmful effects to humans, fauna and flora. Moreover, exposure to PM can cause the development and/or worsening of diseases, mainly respiratory and cardiovascular. The aim of the present study was to evaluate the metals concentration in total suspended particulate matter in the air through total reflection x‐ray fluorescence technique (TXRF). The samples were collected from random points in five neighborhoods in the Metropolitan Region of the state of Rio de Janeiro/Brazil. TXRF measurements were performed using the benchtop TXRF spectrometer S2 PICOFOX. The results showed that the proposed methodology was able to detect the elements Cr, Fe, Ni, Cu, and Zn, in concentrations ranging from 2.0 to 200 ng.m−3. It can be concluded that the study methodology for determining the metal concentrations in air samples is an efficient and low‐cost solution for studying environmental pollution. [ABSTRACT FROM AUTHOR]

Total reflection X‐ray fluorescence (TXRF) is widely used for trace elemental analysis, wherein a thin monochromatic X‐ray beam is typically applied at glancing angles. The actual volume of the sample measured by the instrument (analysis volume) depends on the dimensions of the X‐ray beam and glancing angle, and it is a key feature in sample preparation for TXRF analysis. Herein, the analysis volume, including the analysis region and analysis height, was experimentally evaluated. A thin Au layer approximately 5 nm thick and 1 mm in diameter was prepared at a specific position on a flat glass substrate using a vacuum evaporation device. The position of this Au layer was controlled by manipulating a mask plate with a small hole. Nine samples were prepared at different Au layer positions and analyzed at 8 azimuth angles using a tabletop TXRF instrument. Finally, the Au XRF intensity distribution was visualized on a glass substrate. It was found that the XRF emitted over a diameter of approximately 5 mm was effectively detected using the tabletop TXRF instrument. The analysis height was experimentally evaluated using a thin Au layer deposited on a polyimide film 5 mm in diameter and 5 nm thick. The Au layer height was adjusted by inserting polyimide thin films between the Au layer and the glass substrate. The Au XRF intensity drastically decreased with increasing Au layer height, suggesting that the XRF emitted from the sample is effectively detected at heights of <10 μm by using the described setup. [ABSTRACT FROM AUTHOR]

Grazing-incidence small-angle X-ray scattering (GISAXS) is a widely used method for the characterization of the nanostructure of supported thin films and enables time-resolved in situ measurements. The 2D scattering patterns contain detailed information about the nanostructures within the film and at its surface. However, this information is distorted not only by the reflection of the X-ray beam at the substrate-film interface and its refraction at the film surface but also by scattering of the substrate, the sample holder and other types of parasitic background scattering. In this work, a new, efficient strategy to simulate and fit 2D GISAXS patterns that explicitly includes these effects is introduced and demonstrated for (i) a model case nanostructured thin film on a substrate and (ii) experimental data from a microphase-separated block copolymer thin film. To make the protocol efficient, characteristic linecuts through the 2D GISAXS patterns, where the different contributions dominate, are analysed. The contributions of the substrate and the parasitic background scattering - which ideally are measured separately - are determined first and are used in the analysis of the 2D GISAXS patterns of the nanostructured, supported film. The nanostructures at the film surface and within the film are added step by step to the real-space model of the simulation, and their structural parameters are determined by minimizing the difference between simulated and experimental scattering patterns in the selected linecuts. Although in the present work the strategy is adapted for and tested with BornAgain, it can be easily used with other types of simulation software. The strategy is also applicable to grazingincidence small-angle neutron scattering. [ABSTRACT FROM AUTHOR]

This work presents the results of the analysis of the temperature dependence of the x-ray reflection intensity from solid heavy nitrogen in the ordered phase. The temperature dependence of the behavior of the orientational order parameter and mean square displacement of 15N2 molecules obtained from x-ray data is plotted. Based on the dependencies obtained, the orientational order parameter was determined at 0 K, which is 12% higher than the orientational order parameter obtained in theoretical works. It was found that the heavy nitrogen molecule "freely" rotates in the crystal at temperatures above 45 K. [ABSTRACT FROM AUTHOR]

We investigate the changing geometry of the accretion disc in the X-ray binary GX 339−4 using a combination of spectral and timing models to fit six XMM–Newton observations taken during the end of the 2015 X-ray outburst. We use progressively more complex models of the X-ray reflection spectra, from simple disc lines to full relativistic reflection models. For the timing analysis, the Power Spectral Densities (PSDs) are generated from the light curves in the 0.3–0.7 and 0.7–1.5 keV energy bands. We fit PSD models that assume the standard accretion disc truncates at a specific radius, inside of which are two hot-flow zones, one spectrally soft and one spectrally hard, separated by a transition radius. Finally, we combine and jointly fit the full reflection spectral models and the truncated disc PSD models. Our final model is consistent with the spectroscopic and timing data. It suggests that the truncation radius of the disc increases towards the end of the outburst, which is self-consistent with the obtained reflection fraction that is smaller. During this, the source spectrum becomes harder and the soft excess becomes more prominent. The disc truncation radius that increases as the source flux decreases is intermediate between the results of previous studies. However, our analysis of the model performance leads us to believe that higher quality data and better models are required to fully understand the GX 339-4 system and reduce the effect of systematic uncertainties. [ABSTRACT FROM AUTHOR]

The past 10 years have seen remarkable progress in our capability of analyzing reflection features in the X-ray spectra of accreting black holes. Today X-ray reflection spectroscopy is a mature technique and a powerful tool for studying the accretion process around black holes, measuring black hole spins, and testing Einstein's theory of General Relativity in the strong field regime. However, current reflection models still rely on a number of simplifications and caution is necessary when we derive very precise measurements. In this paper, we study the impact of the returning radiation on our capability of measuring the properties of black holes using X-ray reflection spectroscopy, and in particular on our capability of testing the Kerr black hole hypothesis. While the returning radiation alters the reflection spectrum of the disk, from the analysis of our simulations we find that models without returning radiation can normally recover well the correct black hole spin parameters and can test the Kerr metric. [ABSTRACT FROM AUTHOR]

A new cascade impactor has been developed with the arrangement of the classifying nozzles optimised for analysis of the collected particles by total reflection X-ray fluorescence (TXRF). TXRF offers detection limits in the range of a few pg of absolute mass and therefore poses great potential for the elemental analysis of heavy metals in aerosol particles. To fully exploit this high sensitivity, particles have to be collected in the effective analysis area of the TXRF instrument, which is often smaller than typical deposition patterns of commercial impactors or filter samplers. This is achieved by a novel, compact arrangement of the classifying nozzles within a circular area of a diameter of less than 5 mm. A decreasing density of the nozzle spacing from the inside to the outside of the nozzle cluster allows for constant cross flow conditions, minimising the mutual influence of the individual nozzles. The design of a multi-stage cascade impactor is presented, to individually sample PM10, PM2.5 and PM1 size fractions. Considering the high sensitivity of TXRF analysis, constructive measures have been taken to prevent attrition of impactor material which might lead to methodical blank values. Experimental validation confirms that neither attrition nor cross-contamination can be observed. Furthermore, a new spin-coating method has been developed which makes it possible to apply a thin and defined adhesive layer of grease to the sample carrier with good repeatability. Application of the impactor in a case study at an urban site at Potsdamer Platz, Berlin, Germany shows that at a moderate sampling volume flow rate of 5 litres per minute, the particle mass collected in 30 minutes or less is sufficient for reliable TXRF analysis of heavy metal concentrations (Fe, Zn, Cu, Mn, Pb, Ni) in ambient aerosol. This high time resolution enables snapshot sampling, e.g. to quantify variations in particle source strengths. Overall, the new impactor optimised for TXRF analysis bears great potential to improve the quantification of particulate trace metals and other elements in PM10, PM2.5 and PM1 with high time resolution. [ABSTRACT FROM AUTHOR]

We analysed a dedicated NuSTAR observation of the neutron star low-mass X-ray binary Z-source GX 13+1 to study the timing and spectral properties of the source. From the colour–colour diagram, we conclude that during that observation the source transitioned from the normal branch to the flaring branch. We fitted the spectra of the source in each branch with a model consisting of an accretion disc, a Comptonized blackbody, relativistic reflection (relxillNS), and photoionized absorption (warmabs). Thanks to the combination of the large effective area and good energy resolution of NuSTAR at high energies, we found evidence of relativistic reflection in both the Fe K line profile and the Compton hump present in the 10–25 keV energy range. The inner disc radius is R in ≲ 9.6  rg , which allowed us to further constrain the magnetic field strength to B ≲ 1.8 × 108 G. We also found evidence for the presence of a hot wind leading to photoionized absorption of Fe and Ni, with a Ni overabundance of ∼6 times solar. From the spectral fits, we find that the distance between the ionizing source and the slab of ionized absorbing material is ∼4–40 × 105 km. We also found that the width of the boundary layer extends ∼3 km above the surface of a neutron star, which yielded a neutron star radius R NS ≲ 16 km. The scenario inferred from the spectral modelling becomes self-consistent only for high electron densities in the accretion disc, n e ∼ 1022 − 1023 cm−3, as expected for a Shakura–Sunyaev disc, and significantly above the densities provided by relxillNS models. These results have implications for our understanding of the physical conditions in GX 13+1. [ABSTRACT FROM AUTHOR]

Total reflection X-ray fluorescence (TXRF) has been widely considered as an effective analytical tool for the analysis of a great variety type of polymetallic deposits, because it has many advantages of extremely high sensitivity, high accuracy, minor sample preparation, and the ability of multielement simultaneous analysis. Sample preparation is quite important for TXRF quantitative analysis. Since pretreatment factors, such as sample amount, dispersant type, sample particle size and sample physicochemical properties, are seriously impact the accuracy of results. Based on this reason, investigating an appropriate sample pretreatment strategy is fundamental for accurate assessment of strategic metal elements in polymetallic deposits. This review presents a comprehensive overview of TXRF applications in the field of mineral analysis, including apatite, manganese ore, K-feldspars, granite, copper-nickel sulfide ore, etc. Moreover, the accurate evaluation of TXRF quantitative analysis is detailedly discussed, and the relevant sample preparation methods and preparation factors are also addressed. [ABSTRACT FROM AUTHOR]

We present a new analysis of the Suzaku X-ray spectrum of the Compton-thin Seyfert 2 galaxy NGC 4388. The spectrum above ∼2 keV can be described by a remarkably simple and rather mundane model, consisting of a uniform, neutral spherical distribution of matter, with a radial column density of |$2.58\pm 0.02 \times 10^{23} \ \rm cm^{-2}$|⁠ , and an Fe abundance of |$1.102^{+0.024}_{-0.021}$| relative to solar. The model does not require any phenomenological adjustments to self-consistently account for the low-energy extinction, the Fe Kα and Fe Kβ fluorescent emission lines, the Fe K edge, and the Compton-scattered continuum from the obscuring material. The spherical geometry is not a unique description, however, and the self-consistent, solar abundance MYTORUS model, applied with toroidal and non-toroidal geometries, gives equally good descriptions of the data. In all cases, the key features of the spectrum are so tightly locked together that for a wide range of parameters, a relativistic disc-reflection component contributes no more than |$\sim 2{{\ \rm per\ cent}}$| to the net spectrum in the 2–20 keV band. We show that the commonly invoked explanations for weak X-ray reflection features, namely a truncated and/or very highly ionized disc, do not work for NGC 4388. If relativistically broadened Fe Kα lines and reflection are ubiquitous in Seyfert 1 galaxies, they should also be ubiquitous in Compton-thin Seyfert 2 galaxies. The case of NGC 4388 shows the need for similar studies of more Compton-thin AGN to ascertain whether this is true. [ABSTRACT FROM AUTHOR]