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Beam exit windows are crucial components of any particle accelerator as they provide an interface between the beamline vacuum and target material at atmospheric media. For high beam power machines, special materials and designs are required to withstand high radiation and mechanical loads, while minimizing energy loss during transition and maximizing window lifetime. This research investigates the impact of electron beam exposure to bulk CrMnV and CrMnTiV high entropy alloys (HEAs) with the primary goal of identifying suitable candidate materials for the design of robust and durable exit window settings. The selection criteria include intrinsic characteristics, power dissipation, and mechanical responses. According to the thermodynamic calculations, both equiatomic CrMnV and the addition of 7% of Ti with equiatomic CrMnV yield solid-solutions phases. The structural and mechanical properties of CrMnV and CrMnTiV samples were tested using field emission scanning electron microscopy, atomic force microscopy, scanning electron microcopy with energy dispersive x-ray spectroscopy, x-ray diffraction, and nanoindentation before and after exposure to a dose of ∼66 kGy from a 10 MeV e-beam accelerator. Despite exhibiting beam transmission characteristics comparable to Cr and V, the indentation hardness of HEAs exceeded that of the Cr and V samples by five to six times. The examination of the CrMnTiV irradiated samples revealed organized deformation patterns depicting new features, which we suspect twinning and twin boundaries due to the addition of Ti to CrMnV. Ti, a hexagonal-close-packed crystal structure, is commonly known for deformation twinning behavior. [ABSTRACT FROM AUTHOR]

We report recent enhancements to the online atomic database at the Ohio State University, NORAD-Atomic-Data, that provide various parameters for radiative and collisional atomic processes dominant in astrophysical plasma. NORAD stands for Nahar Osu RADiative. The database belongs to the data sources, especially for the latest works, of the international collaborations of the Opacity Project and the Iron Project. The contents of the database are calculated values for energies, oscillator strengths, radiative decay rates, lifetimes, cross-sections for photoionization, electron-ion recombination cross-sections, and recombination rate coefficients. We have recently expanded NORAD-Atomic-Data with several enhancements over those reported earlier. They are as follows: (i) We continue to add energy levels, transition parameters, cross-sections, and recombination rates for atoms and ions with their publications. (ii) Recently added radiative atomic data contain a significant amount of transition data for photo-absorption spectral features corresponding to the X-ray resonance fluorescence effect, showing prominent wavelength regions of bio-signature elements, such as phosphorus ions, and emission bumps of heavy elements, such as of lanthanides, which may be created in a kilonova event. We are including (iii) collisional data for electron-impact-excitation, (iv) experimental data for energies and oscillator strengths for line formation, (v) experimental cross-sections for photoionization that can be applied for benchmarking and other applications, and (vi) the introduction of a web-based interactive feature to calculate spectral line ratios at various plasma temperature and density diagnostics, starting with our recently published data for P II. We presented a summary description of theoretical backgrounds for the computed data in the earlier paper. With the introduction of experimental results in the new version of NORAD, we present a summary description of measurement of high-resolution photoionization cross-sections at an Advanced Light Source of LBNL synchrotron set-up and briefly discuss other set-ups. These additions should make NORAD-Atomic-Data more versatile for various applications. For brevity, we provide information on the extensions and avoid repetition of data description of the original paper.

The broad emission bump in the electromagnetic spectra observed following the detection of gravitational waves created during the kilonova event of the merging of two neutron stars in August 2017, named GW170817, has been linked to the heavy elements of lanthanides (Z = 57–71) and a new understanding of the creation of heavy elements in the r-process. The initial spectral emission bump has a wavelength range of 3000–7000 Å, thus covering the region of ultraviolet (UV) to optical (O) wavelengths, and is similar to those seen for lanthanides. Most lanthanides have a large number of closely lying energy levels, which introduce extensive sets of radiative transitions that often form broad regions of lines of significant strength. The current study explores these broad features through the photoabsorption spectroscopy of 25 lanthanide ions, Ho I-III, Er I-IV, Tm I-V, Yb I-VI, and Lu I-VII. With excitation only to a few orbitals beyond the ground configurations, we find that most of these ions cover a large number of bound levels with open 4f orbitals and produce tens to hundreds of thousands of lines that may form one or multiple broad features in the X-ray to UV, O, and infrared (IR) regions. The spectra of 25 ions are presented, indicating the presence, shapes, and wavelength regions of these features. The accuracy of the atomic data used to interpret the merger spectra is an ongoing problem. The present study aims at providing improved atomic data for the energies and transition parameters obtained using relativistic Breit–Pauli approximation implemented in the atomic structure code SUPERSTRUCTURE and predicting possible features. The present data have been benchmarked with available experimental data for the energies, transition parameters, and Ho II spectrum. The study finds that a number of ions under the present study are possible contributors to the emission bump of GW170817. All atomic data will be made available online in the NORAD-Atomic-Data database.

We report study of Cl III for its large number of fine structure bound levels, 890, with n ≤ 10 and l ≤ 9, and 1/2 ≤ j ≤ 19/2 of even and odd parities with spectroscopic designation and photoionization cross sections (σPI) of the levels revealing various characteristic features. Various resonant structures and the shapes of the background, and their interference in σPI are illustrated for the ground, excited equivalent electron, low and high lying excited levels with single valence electron, and effects of fine structure couplings. σPI of the ground level shows Rydberg series of resonances on smooth background, and of equivalent electron levels producing strong closely spaced Rydberg series of resonances belonging to the low lying core ion excitation thresholds. They will impact applications in low temperature plasma. For the single valence electron excited levels, we find that σPI of low lying excited states are dominated by Rydberg series of resonances and of high lying excited states exhibit prominent broad feature of Seaton resonances. Partial photoionization cross sections of the ground level for leaving the core ion in the ground and various excited levels are also presented for applications in plasma modeling. The study was carried out in relativistic Breit–Pauli R-matrix method using a large close coupling wave function expansion of 45 levels of the core ion configurations 3s23p2, 3s3p3, 3s23p3d, 3s23p4s, 3s3p23d, and 3p4 with closed 1s, 2s, 2p orbitals. They belong to the optimized set of 13 configurations of Cl IV, 3s23p2, 3s3p3, 3s23p3d, 3s23p4s, 3s23p4p, 3s23p4d, 3s3p23d, 3s3p24s, 3s3p24p, 3p4, 3p33d, 3p34s, and 3p34p. Cl III energies are in good agreement with measured values. σPI features of low lying levels were benchmark with observation carried out at Advanced Light Source at LBNL with very good agreement. The present set of high accuracy data should complete for any practical applications. [ABSTRACT FROM AUTHOR]

Phosphorus (P), a basic element of life, has been a least studied element due to its poor presence in astrophysical spectra. However, search for the P lines has increased considerably with discoveries of exoplanets and are being detected by high resolution and sophisticated astronomical observatories, e.g., James Webb Space Telescope (JWST). JWST may provide a clue for life with detection of P in its infrared (IR) region. Identification of the element and analysis of the observed spectra will require high accuracy data for atomic processes that produces lines and their predicted features. The present study focuses on these needs and reports systematically regions of wavelengths, from X-ray to IR, that show prominent lines by the 15 individual ionization stages of phosphorus, P I–P XV for the first time. We present large amount of relevant atomic data for energies, transition parameters, and lifetimes obtained in relativistic Breit–Pauli approximation using the R-matrix method and atomic structure program SUPERSTRUCTURE. Our spectral features for the 15 ions, P I–P XV, predict strengths of lines in various wavelength regions. They show dominance of P I and P II in the IR region and other ions in the ultraviolet and optical regions often stretching to IR in the continuum. For determination of accuracy, we have made extensive comparisons of our atomic data with available experimental and theoretical values. Based on these, our results and features are expected to provide precise plasma diagnostics and astrophysical modeling. [ABSTRACT FROM AUTHOR]

The main focus of this study is to investigate the radioactivity concentration, and the hazardous effects of using paint materials for decorative purposes which are available on the market. The gamma radiation from these collected paint samples is detected by using the High-Purity Germanium (HPGe) detector. A total of 20 samples from four brands and five different colours of each brand were collected for this experiment. From this study, the activity concentrations of Ra-226, Th-232 and K-40 in paint samples were found to be varied from 2.20 ± 0.98 to 60.22 ± 7.37 Bq kg−1 with an average value of 20.88 ± 4.05 Bq kg−1, 8.01 ± 3.54 to 87.07 ± 7.68 Bq kg−1 with an average value 28.19 ± 7.70 Bq kg−1 and 21.98 ± 19.39 to 517.92 ± 47.08 Bq kg−1 with an average value 221.70 ± 32.06 Bq kg−1, respectively. The total annual effective dose rate ranges from 0.04 to 0.25 mSvy−1 with an average of 0.15 mSvy−1. [ABSTRACT FROM AUTHOR]

This study investigated students' overall perceptions of assignments in an active learning class based on their learning style, course engagement, understanding of content, industry relevance, collaborative learning, and value of the assignments. A total of six terms were surveyed, with a total of 250 participants. Students agreed that the assignments helped them learn industry terminology, increased their skill sets, were engaging, and prepared them for entering the job market. Group assignments aided in understanding content in more depth and developing critical thinking skills and problem-solving. [ABSTRACT FROM AUTHOR]

Background: The sources of milk play a significant role on overall milk quality. Therefore, the current study was intended to evaluate the quality (physiochemical, compositional, and microbiological) and detect the adulterants in milk. Methods: A total of 200 milk samples were collected during mid of October to mid of December 2022 from four sources viz. Farmgate (50), Milkman (50), Bazar (50), and Branded packet milk (50). Milk samples were examined for various physiochemical, compositional, microbiological properties, and existence of adulterants. Data were analyzed by one way ANOVA and differences were determined by least significant difference test using RStudio. Results: Physiochemical analysis found significant variation in titratable acidity, protein, fat, salt, Solids-Not-Fat, and Total-Solids content among the sources (p<0.05), while lactose content was found non-significant. The highest (0.17%) and the lowest (0.13%) values for acidity were found in samples obtained from Milkman and Branded packet milk, respectively. Milk sample collected from Farmgate was found significantly higher in protein, fat, lactose, Solids-Not-Fat, and Total-Solids content than the other sources. In microbiological analysis, significant lower Total Viable Count, Total Coliform Count, and Escherichia coli Count were observed in Branded packet milk compared to the milk from Farmgate, Milkman, and Bazar source (p<0.001). In adulteration examinations, only neutralizers (sodium carbonate and bicarbonate) and nitrates were found positive in milk sample collected from Milkman, Farmgate, and Bazar, and their frequency was varied significantly (p<0.001). Overall, the milk obtained from Farmgate was better in terms of nutrient composition and physiochemical properties than the other sources but in respect to microbiological quality, Branded packet milk was found more hygienic. Conclusion: The study found that the variance in milk sources led to changes in the microbial load, physical appearance, and nutritional content of milk. The present study investigated that the addition of different adulterants and variation in time interval (milking to selling) are the main reasons for the deterioration of milk. [ABSTRACT FROM AUTHOR]

Nahid Sultana Department of Computer Science, College of Computer Science and Information Technology, Imam Abdulrahman Bin Faisal University, Dammam, Saudi ArabiaCorrespondence: Nahid Sultana Department of Computer ScienceCollege of Computer Science and Information Technology, Imam Abdulrahman Bin Faisal University, Dammam, Saudi ArabiaTel +966 13 333 2029Email nszakir@iau.edu.saBackground: The incidence of skin cancer has increased over the past few years, owing to excessive exposure to ultraviolet (UV) radiation. Over the past decade, protection against solar radiation has been highly encouraged in numerous public health education campaigns. The adopted sun protection practices include avoiding exposure to the sun, using protective clothing, and applying sunscreen. The aim of this paper was to analyze the awareness and attitudes towards sun protection practices in some regions of the Arabian Peninsula.Objective: The main objective of this study is to estimate the level of sun protection practices and determine the factors that have a significant impact on the level of adoption of sun protection practices by residents in the Arabian Peninsula.Methods: A 35-question self‐reporting online questionnaire to evaluate the sun protection measures adopted by the residents was distributed in the Kingdom of Saudi Arabia and Kingdom of Bahrain. The survey was conducted from January 2018 to May 2019, and a total 830 responses were collected for analysis. The data were analyzed using the statistical software SPSS. The chi-squared test and Spearman’s correlation were performed to determine the association of the sun protection level with factors concerning the socio-demographic characteristics, sun sensitivity, health-conscious lifestyle, adopted sun protection measures, and general awareness about the UV index, skin cancer, and vitamin D. Logistic regression classification was applied in developing the empirical model to predict the sun protection level of the residents.Results: Based on the analysis, only 34% of the total 830 respondents use sunscreen and most of the sunscreen users are female. The three most popular sun protection practices are: 1) avoiding exposure to the sun during peak hours, 2) using protective clothing, and 3) using sunglasses. The results indicate that 22% of respondents use a low level of sun protection, 53% use a medium level of protection, while 25% of respondents use a high level of sun protection. Many of the respondents understand that exposure to the sun can cause skin cancer and skin aging, while 54% of the respondents still believe that a suntan can be healthy if sunburn is avoided. Thirty percent of the participants of this study are aware of the UV index, and only 20% of all respondents know the correct meaning of the UV index. The overall predictive accuracy of the constructed logistic regression model is 67%. Based on the results of the logistic regression model, the five most significant factors of the sun protection level are: 1) perception that the sun can cause skin aging, or not, 2) age, 3) awareness of the dangerous effects of sun exposure, 4) income with respect to expenses, and 5) taking the UV index into consideration during exposure to the sun.Conclusion: Most of the respondents are aware about sun protection. However, the sun protection level of the residents is still inadequate. An efficient strategy of increasing the awareness of the effective use of sun protection systems must be established based on the significant factors to prevent skin cancer.Keywords: sun protection, sunscreen, UV index, skin cancer, vitamin D

Photoionization of Cl III ions into Cl IV was studied theoretically using the ab initio relativistic Breit–Pauli R-matrix (BPRM) method and experimentally at the Advanced Light Source (ALS) synchrotron at the Lawrence Berkeley National Laboratory. A relative-ion-yield spectrum of Cl IV was measured with a photon energy resolution of 10 meV. The theoretical study was carried out using a large wave-function expansion of 45 levels of configurations 3s23p2, 3s3p3, 3s23p3d, 3s23p4s, 3s3p23d, and 3p4. The resulting spectra are complex. We have compared the observed spectrum with photoionization cross sections (σPI) of the ground state 3s23p3(4S3/2o) and the seven lowest excited levels 3s23p3(2D5/2o), 3s23p3(2D3/2o), 3s23p3(2P3/2o), 3s23p3(2P1/2o), 3s3p4(4P5/2), 3s3p4(4P3/2) and 3s3p4(4P1/2) of Cl III, as these can generate resonances within the energy range of the experiment. We were able to identify most of the resonances as belonging to various specific initial levels within the primary Cl III ion beam. Compared to the first five levels, resonant structures in the σPI of excited levels of 3s3p4 appear to have a weaker presence. We have also produced combined theoretical spectra of the levels by convolving the cross sections with a Gaussian profile of experimental width and summing them using statistical weight factors. The theoretical and experimental features show good agreement with the first five levels of Cl III. These features are also expected to elucidate the recent observed spectra of Cl III by Sloan Digital Scan Survey project.