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We herein report the development of the sputtering process for the fabrication of low-temperature thin film solid oxide fuel cells (TF-SOFCs) supported by anodized aluminum oxide (AAO). The process development has been conducted for each component, anode, electrolyte, electrolyte/cathode interlayer, and cathode to scale up the cell from 1cm x 1cm to 15 cm x 15 cm. In order to fabricate a uniform thin film regardless of the size of AAO, sputtering conditions such as power, pressure, angle, target-to-substrate distance (TSD), and time have been developed. The recipe for the anode and cathode has aimed at a porous structure with nano-grains for high reactivity. In contrast, the recipe for the electrolyte has been optimized for thickness uniformity and high density. With these sputtering recipes TF-SOFCs with the required microstructure and thickness uniformity have been successfully fabricated on 15 cm x 15 cm AAO substrates.

A novel cell design and its corresponding manufacturing processes are being evaluated to demonstrate a highly efficient, durable, and reduction-oxidation (redox) resistant solid oxide electrolysis cell (SOEC) technology for hydrogen production. The cell design includes a unique 3D hydrogen electrode configuration composed of two layers ‒ a 3D hydrogen electrode support layer (for improved cell redox resistance) and an exsolved perovskite hydrogen electrode active layer (for enhanced cell performance and increased durability). The hydrogen electrode support layer consists of specifically designed 3D networks of electrode materials; tetragonal zirconia (TZ) and Ni-yttria stabilized zirconia (YSZ). Each phase is topologically connected throughout the electrode with controlled geometry and connectivity. The TZ component plays a role as an outer frame to provide structural support, while the Ni-YSZ component inside the TZ frame imparts electrical conductivity for the hydrogen electrode support layer. The hydrogen electrode active layer, which primarily supports electrochemical reaction, is a nickel-substituted perovskite that will exsolve nickel nanoparticles on the oxide surface when exposed to a reducing environment and is redox-reversible. A fabrication scheme being developed for this cell design incorporates a printing-based additive manufacturing (AM) process for producing the 3D hydrogen electrode. This paper presents the progress to date in developing the printing fabrication process for the 3D hydrogen electrode support and evaluating exsolved nickel-substituted perovskite for the hydrogen electrode active layer.

Heavy metal pollution in the soil environment is a worldwide environmental problem as it has negative effects on both human health and the environment. Remediation of heavy metal-contaminated soil is essential to improve soil quality, provide land resources for agricultural production, and protect human and animal health and the ecological environment. There is the possibility of remediating these contaminated soils through the use of several heavy metal absorbing plants and Superabsorbent polymers. Superabsorbent polymers (SAPs) are 3D polymer networks having hydrophilic nature, which can swell, absorb and hold a large amount of water or aqueous solutions in their network. This study evaluates the effect of superabsorbent polymer on Pb absorption capacity of Vetiver (Vetiveria zizanioides.L) that was grown on contaminated soil in Trai Cau iron ore dumpsite, Dong Hy district, Thai Nguyen province. The experiment was designed with five recipes and three replicates. The contents of SAP studied were 0, 0.6, 0.8, and 1.0 g/kg of soil. Uncontaminated soil was used as the control treatment. In the supplemented recipe of SAP, Vetiver showed better Pb treatment efficiency than the recipes without adding polymers. After 120 days of planting, SAP increased the tolerance and Pb absorption of Vetiver, improving soil properties. The best Pb treatment efficiency is achieved when using SAP with content from 0.8-1.0 g/kg soil.

This paper aims to evaluate the roles of charitable works at Kinh Pagodas in Soc Trang province and provides recommendations to improve the functions of these charitable works. The research employed combined research methods, including key informant participants and interviews with 255 related stakeholders. Results indicated that charitable works in pagodas are targeted toward many different purposes. The activities are also different between pagodas. The charitable works are varied and these activities play an important role in local communities. This paper also provides recommendations for improving the functions of charitable works at pagodas in Soc Trang province in which the improvement role of local government is the most important factor to strengthen the function of charity activities in pagodas.

Haze is the suspension of atmospheric particles which is sufficient to reduce the visibility. Image dehazing refers to the processing tasks that lessen this negative effect. In this work, an alternative approach to single-image dehazing is developed which skips solving the haze formation equation, while still respects its hypothesis. In this method, we generated multiple under-exposed images from a single hazy input, followed by a detail enhancement process. Such resulting images were then merged using weights calculated based on the Dark Channel Prior assumption and overcame luminance enhancement. The visual improvement has been validated by both qualitative and quantitative evaluations.

Altermagnets are an emerging third elementary class of magnets. Unlike ferromagnets, their distinct crystal symmetries inhibit magnetization while, unlike antiferromagnets, they promote strong spin polarization in the band structure. The corresponding unconventional mechanism of timereversal symmetry breaking without magnetization in the electronic spectra has been regarded as a primary signature of altermagnetism, but has not been experimentally visualized to date. We directly observe strong time-reversal symmetry breaking in the band structure of altermagnetic RuO$_2$ by detecting magnetic circular dichroism in angle-resolved photoemission spectra. Our experimental results, supported by ab initio calculations, establish the microscopic electronic-structure basis for a family of novel phenomena and functionalities in fields ranging from topological matter to spintronics, that are based on the unconventional time-reversal symmetry breaking in altermagnets.

Water is vital for life, and without it, biomolecules and cells cannot maintain their structures and functions. The remarkable properties of water originate from its ability to form hydrogen-bonding networks and dynamics, which the connectivity constantly alters because of the orientation rotation of individual water molecules. Experimental investigation of the dynamics of water, however, has proven challenging due to the strong absorption of water at terahertz frequencies. In response, by employing a high-precision terahertz spectrometer, we have measured and characterized the terahertz dielectric response of water from supercooled liquid to near the boiling point to explore the motions. The response reveals dynamic relaxation processes corresponding to the collective orientation, single-molecule rotation, and structural rearrangements resulting from breaking and reforming hydrogen bonds in water. We have observed the direct relationship between the macroscopic and microscopic relaxation dynamics of water, and the results have provided evidence of two liquid forms in water with different transition temperatures and thermal activation energies. The results reported here thus provide an unprecedented opportunity to directly test microscopic computational models of water dynamics.

Logic locking has been a promising solution to many hardware security threats, such as intellectual property infringement and overproduction. Due to the increased attention that threats have received, many efficient specialized attacks against logic locking have been introduced over the years. However, the ability of an adversary to manipulate a locked netlist prior to mounting an attack has not been investigated thoroughly. This paper introduces a resynthesis-based strategy that utilizes the strength of a commercial electronic design automation (EDA) tool to reveal the vulnerabilities of a locked circuit. To do so, in a pre-attack step, a locked netlist is resynthesized using different synthesis parameters in a systematic way, leading to a large number of functionally equivalent but structurally different locked circuits. Then, under the oracle-less threat model, where it is assumed that the adversary only possesses the locked circuit, not the original circuit to query, a prominent attack is applied to these generated netlists collectively, from which a large number of key bits are deciphered. Nevertheless, this paper also describes how the proposed oracle-less attack can be integrated with an oracle-guided attack. The feasibility of the proposed approach is demonstrated for several benchmarks, including remarkable results for breaking a recently proposed provably secure logic locking method and deciphering values of a large number of key bits of the CSAW'19 circuits with very high accuracy., 8 pages, 7 figures, conference

The relationship between the tendencies towards rigidity (measured by shear modulus, G) and hardness (measured by Vickers hardness, HV) of early transition metal (ETM)-based refractory high-entropy alloys (RHEA) and bond parameters (i.e., valence electron concentration (VEC), enthalpy of mixing (ΔHmix)) was investigated. These bond parameters, VEC and ΔHmix, are available from composition and tabulated data, respectively. Based on our own data (9 samples) and those available from the literatures (47 + 27 samples), it seems that for ETM-based RHEAs the G and HV characteristics have a close correlation with the bonding parameters. The room temperature value of G and HV increases with the VEC and with the negative value of ΔHmix. Corresponding equations were deduced for the first time through multiple linear regression analysis, in order to help design the mechanical properties of ETM refractory high-entropy alloys.

Proteins and water couple dynamically over a wide range of time scales. Motivated by their central role in protein function, protein-water dynamics and thermodynamics have been extensively studied for structured proteins, where correspondence to structural features has been made. However, properties controlling intrinsically disordered protein (IDP)-water dynamics are not yet known. We report results of megahertz-to-terahertz dielectric spectroscopy and molecular dynamics simulations of a group of IDPs with varying charge content along with structured proteins of similar size. Hydration water around IDPs is found to exhibit more heterogeneous rotational and translational dynamics compared with water around structured proteins of similar size, yielding on average more restricted dynamics around individual residues of IDPs, charged or neutral, compared with structured proteins. The on-average slower water dynamics is found to arise from excess tightly bound water in the first hydration layer, which is related to greater exposure to charged groups. The more tightly bound water to IDPs correlates with the smaller hydration shell found experimentally, and affects entropy associated with protein-water interactions, the contribution of which we estimate based on the dielectric measurements and simulations. Water-IDP dynamic coupling at terahertz frequencies is characterized by the dielectric measurements and simulations.

In this work, we systematically examine the electronic features and contact types of van der Waals heterostructures (vdWHs) combining single-layer boron phosphide (BP) and Janus Ga2SSe using first-principles calculations.

We propose novel 2D Janus XMoGeN2 (X = S, Se and Te) monolayers using first-principles prediction.

Many functionally relevant ferroic phenomena in quantum materials can be manipulated by driving the lattice coherently with optical and terahertz pulses. New physical phenomena and non-equilibrium phases that have no equilibrium counterpart have been discovered following these protocols. The underlying structural dynamics has been mostly studied by recording the average atomic position along dynamical structural coordinates with elastic scattering methods. However, crystal lattice fluctuations, which are known to influence phase transitions in equilibrium, are also expected to determine these dynamics but have rarely been explored. Here, we study the driven dynamics of the quantum paraelectric SrTiO3, in which mid-infrared drives have been shown to induce a metastable ferroelectric state. Crucial in these physics is the competition between the polar instability and antiferrodistortive rotations, which in equilibrium frustrate the formation of long-range ferroelectricity. We make use of high intensity mid-infrared optical pulses to resonantly drive a Ti-O stretching mode at 17 THz, and we measure the resulting change in lattice fluctuations using time-resolved x-ray diffuse scattering at a free electron laser. After a prompt increase, we observe a long-lived quench in R-point antiferrodistortive lattice fluctuations. The enhancement and reduction in lattice fluctuations are explained theoretically by considering fourth-order nonlinear phononic interactions and third-order coupling to the driven optical phonon and to lattice strain, respectively. These observations provide a number of new and testable hypotheses for the physics of light-induced ferroelectricity.

Background: Increased data availability has prompted the creation of clinical decision support systems. These systems utilise clinical information to enhance health care provision, both to predict the likelihood of specific clinical outcomes or evaluate the risk of further complications. However, their adoption remains low due to concerns regarding the quality of recommendations, and a lack of clarity on how results are best obtained and presented. Methods: We used autoencoders capable of reducing the dimensionality of complex datasets in order to produce a 2D representation denoted as latent space to support understanding of complex clinical data. In this output, meaningful representations of individual patient profiles are spatially mapped in an unsupervised manner according to their input clinical parameters. This technique was then applied to a large real-world clinical dataset of over 12,000 patients with an illness compatible with dengue infection in Ho Chi Minh City, Vietnam between 1999 and 2021. Dengue is a systemic viral disease which exerts significant health and economic burden worldwide, and up to 5% of hospitalised patients develop life-threatening complications. Results: The latent space produced by the selected autoencoder aligns with established clinical characteristics exhibited by patients with dengue infection, as well as features of disease progression. Similar clinical phenotypes are represented close to each other in the latent space and clustered according to outcomes broadly described by the World Health Organisation dengue guidelines. Balancing distance metrics and density metrics produced results covering most of the latent space, and improved visualisation whilst preserving utility, with similar patients grouped closer together. In this case, this balance is achieved by using the sigmoid activation function and one hidden layer with three neurons, in addition to the latent dimension layer, which produces the output (Pearson, 0.840; Spearman, 0.830; Procrustes, 0.301; GMM 0.321). Conclusion: This study demonstrates that when adequately configured, autoencoders can produce two-dimensional representations of a complex dataset that conserve the distance relationship between points. The output visualisation groups patients with clinically relevant features closely together and inherently supports user interpretability. Work is underway to incorporate these findings into an electronic clinical decision support system to guide individual patient management.

Many functionally relevant ferroic phenomena in quantum materials can be manipulated by driving the lattice coherently with optical and terahertz pulses. New physical phenomena and non-equilibrium phases that have no equilibrium counterpart have been discovered following these protocols. The underlying structural dynamics has been mostly studied by recording the average atomic position along dynamical structural coordinates with elastic scattering methods. However, crystal lattice fluctuations, which are known to influence phase transitions in equilibrium, are also expected to determine these dynamics but have rarely been explored. Here, we study the driven dynamics of the quantum paraelectric SrTiO3, in which mid-infrared drives have been shown to induce a metastable ferroelectric state. Crucial in these physics is the competition between the polar instability and antiferrodistortive rotations, which in equilibrium frustrate the formation of long-range ferroelectricity. We make use of high intensity mid-infrared optical pulses to resonantly drive a Ti-O stretching mode at 17 THz, and we measure the resulting change in lattice fluctuations using time-resolved x-ray diffuse scattering at a free electron laser. After a prompt increase, we observe a long-lived quench in R-point antiferrodistortive lattice fluctuations. The enhancement and reduction in lattice fluctuations are explained theoretically by considering fourth-order nonlinear phononic interactions and third-order coupling to the driven optical phonon and to lattice strain, respectively. These observations provide a number of new and testable hypotheses for the physics of light-induced ferroelectricity.

Network science offers powerful tools to model complex social systems. Most social network science research focuses on topological networks by simply considering the binary state of the links, i.e., their presence or absence. Nonetheless, complex social systems present heterogeneity in link interactions (link weight), and accounting for this heterogeneity, it is mandatory to design reliable social network models. Here, we revisit the topic of weighted social networks (WSNs). By summarizing the main notions, findings, and applications in the field of WSNs, we outline how WSN methodology may improve the modeling of several real problems in social sciences. We are convinced that WSNs may furnish ideas and insights to open interesting lines of new research in the social sciences.

PURPOSE: Sperm DNA fragmentation (SDF) testing was recently added to the sixth edition of the World Health Organization laboratory manual for the examination and processing of human semen. Many conditions and risk factors have been associated with elevated SDF; therefore, it is important to identify the population of infertile men who might benefit from this test. The purpose of this study was to investigate global practices related to indications for SDF testing, compare the relevant professional society guideline recommendations, and provide expert recommendations. MATERIALS AND METHODS: Clinicians managing male infertility were invited to take part in a global online survey on SDF clinical practices. This was conducted following the CHERRIES checklist criteria. The responses were compared to professional society guideline recommendations related to SDF and the appropriate available evidence. Expert recommendations on indications for SDF testing were then formulated, and the Delphi method was used to reach consensus. RESULTS: The survey was completed by 436 experts from 55 countries. Almost 75% of respondents test for SDF in all or some men with unexplained or idiopathic infertility, 39% order it routinely in the work-up of recurrent pregnancy loss (RPL), and 62.2% investigate SDF in smokers. While 47% of reproductive urologists test SDF to support the decision for varicocele repair surgery when conventional semen parameters are normal, significantly fewer general urologists (23%; p=0.008) do the same. Nearly 70% would assess SDF before assisted reproductive technologies (ART), either always or for certain conditions. Recurrent ART failure is a common indication for SDF testing. Very few society recommendations were found regarding SDF testing. CONCLUSIONS: This article presents the largest global survey on the indications for SDF testing in infertile men, and demonstrates diverse practices. Furthermore, it highlights the paucity of professional society guideline recommendations. Expert recommendations are proposed to help guide clinicians.

Aim of study: To develop and cross-validate simultaneous modeling systems for estimating components and total tree aboveground biomass and carbon of Litsea glutinosa in an agroforestry model with cassava. Area of study: In the Central Highlands of Vietnam, the agroforestry model widely planted on fallow land of ethnic minorities is a mixture of 65% L. glutinosa in combination with 35% cassava (Manihot esculenta). Material and methods: Twenty-two 300-m2 circular sample plots were located, representing the range of tree age, plantation density, and a 6-7 year rotation cycle. In each sample plot, one selected tree with a diameter at breast height equal to the plot quadratic mean diameter was destructively sampled. The relationships among tree aboveground biomass and carbon (AGB/AGC) and their components with dendrometric variables diameter, height, age, and crown area were examined using factor analysis. To fit systems of equations for AGB/AGC and their components, we compared two methods: weighted nonlinear least-squares (WNLS) and weighted nonlinear seemingly unrelated regression (WNSUR). Main results: The results of the leave-one-out cross-validation showed that the simultaneous WNSUR approach to modeling systems of four tree components, total biomass, and carbon provided better results than independent WNLS models. Research highlights: The simultaneous WNSUR modeling system provided improved and reliable estimates of tree components, total biomass, and carbon for L. glutinosa in an agroforestry model with cassava compared to independently fitted WNLS models.

Low temperature tensile and impression creep tests were carried out on an ultrafine-grained 7xxx series Al–4.8Zn–1.2 Mg–0.14Zr (wt%) alloy, which can be deformed for maximum elongation of about 200% at 150 °C. The characteristics of the deformation process, such as the strain rate sensitivity (SRS) and activation energy (Q) were determined by considering also the effect of threshold stress. Relatively high SRS of$$\sim$$∼0.35 and low activation energy of$$\sim$$∼92 kJ/mole were obtained, confirming the super ductility of the investigated ultrafine-grained alloy in the low temperature region between 140 and 160 °C.Graphical abstract

The important benefits of ultrafine-grained (UFG) alloys for various applications stem from their enhanced superplastic properties. However, decreasing the temperature of superplasticity and providing superplastic forming at lower temperatures and higher strain rates is still a priority. Here, we disclose, for the first time, the mechanism by which grain boundary sliding and rotation are enhanced, when UFG materials have grain boundary segregation of specific alloying elements. Such an approach enables achieving superplasticity in commercial Al alloys at ultralow homologous temperatures below 0.5 (i.e. below 200°C), which is important for developing new efficient technologies for manufacturing complex-shaped metallic parts with enhanced service properties. For the first time, ultralow-temperature superplasticity is found in commercial 7xxx Al alloy. This discovery enables the development of new technologies for the superplastic forming of complex-shaped products with enhanced service properties.

Motivated by the successful synthesis of two-dimensional MoSi

The ability to study cancer-immune cell communication across the whole tumor section without tissue dissociation is needed, especially for cancer immunotherapy development, which requires understanding of molecular mechanisms and discovery of more druggable targets. In this work, we assembled and evaluated an integrated experimental framework and analytical process to enable genome-wide scale discovery of ligand-receptors potentially used for cellular crosstalks, followed by targeted validation. We assessed the complementarity of four different technologies: single-cell RNA sequencing and Spatial transcriptomic (measuring over >20,000 genes), RNA In Situ Hybridization (RNAscope, measuring 4-12 genes) and Opal Polaris multiplex protein staining (4-9 proteins). To utilize the multimodal data, we implemented existing methods and also developed STRISH (Spatial TRanscriptomic In Situ Hybridization), a computational method that can automatically scan across the whole tissue section for local expression of gene (e.g. RNAscope data) and/or protein markers (e.g. Polaris data) to recapitulate an interaction landscape across the whole tissue. We evaluated the approach to discover and validate cell-cell interaction in situ through in-depth analysis of two types of cancer, basal cell carcinoma and squamous cell carcinoma, which account for over 70% of cancer cases. We showed that inference of cell-cell interactions using scRNA-seq data can misdetect or detect false positive interactions. Spatial transcriptomics still suffers from misdetecting lowly expressed ligand-receptor interactions, but reduces false discovery. RNAscope and Polaris are sensitive methods for defining the location of potential ligand receptor interactions, and the STRISH program can determine the probability that local gene co-expression reflects true cell-cell interaction. We expect that the approach described here will be widely applied to discover and validate ligand receptor interaction in different types of solid cancer tumors.

Objectives Community-onset bloodstream infections (BSIs) caused by carbapenemase-producing Enterobacter cloacae complex (ECC) species are increasing internationally. This observation suggests that ECC are emerging pathogens, requiring for detailed understanding on their genomic epidemiology including transmission dynamics and antimicrobial resistance profiles. Patients and methods We performed WGS on 79 Enterobacter spp. isolated from the patients with clinically significant BSIs and admitted to emergency department of a major tertiary hospital in Nepal between April 2016 and October 2017. Results We identified 5 species and 13 STs of ECC. Enterobacter xiangfangensis ST171, one of the globally emerging carbapenem resistant ECC clones with epidemic potential, was the most prevalent (42%). Phylogenetic analysis showed a large (>19 400 SNPs) core genome SNP distance across major STs, which was minimal ( Conclusions Our study highlighted that MDR ECC clones are important pathogens of BSIs in community. Though of low prevalence, carbapenem resistance observed in our ECC isolates raised concern about further community dissemination, underscoring the need for community surveillance to identify MDR ECC clones with epidemic potential.

Public blockchains are decentralized networks where each participating node executes the same decision-making process. This form of decentralization does not scale well because the same data are stored on each network node, and because all nodes must validate each transaction prior to their confirmation. One solution approach decomposes the nodes of a blockchain network into subsets called "shards", each shard processing and storing disjoint sets of transactions in parallel. To fully benefit from the parallelism of sharded blockchains, the processing load of shards must be evenly distributed. However, the problem of computing balanced workloads is theoretically hard and further complicated in practice as transaction processing times are unknown prior to be assigned to shards. In this paper we introduce a dynamic workload-balancing algorithm where the allocation strategy of transactions to shards is periodically adapted based on the recent workload history of shards. Our algorithm is an adaptation to sharded blockchains of a consensus-based load-balancing algorithm. It is a fully distributed algorithm inline with network based applications such as blockchains. Some preliminary results are reported based on simulations that shard transactions of three well-known blockchain platforms.

Cenozoic strike-slip deformation and associated basin formation in Indochina provide critical clues on crustal response during India-Asia collision. Typically, Indochina is considered a rigid block during continental extrusion. We demonstrate that the Song Ca-Rao Nay Fault System (SCRNFS) in north central Vietnam and its offshore extension, the Hue Sub-basin, subdivided Indochina into discrete blocks. Using an integrated dataset including topographic maps, geologic maps, onshore fieldworks, and offshore seismic and well interpretation, the structural evolution of the SCRNFS and Hue Sub-basin is investigated. During Late Oligocene, the SCRNFS initiated with right-lateral motion, causing pull-apart onshore and Hue Sub-basin opening offshore. The End-Oligocene inversion affecting the northern Song Hong Basin also caused a major NE–SW reverse fault in the Hue Sub-basin. In Early Miocene, rifting resumed in the Hue Sub-basin with accelerated faulting and westward rift migration in the south. This is distinct from the Song Hong Basin, where the main rift period was Eocene(?) – Oligocene, and the Early Miocene only features mild extension. During latest Early Miocene – earliest Middle Miocene, the SCRNFS switched to left-lateral transpression. This caused inversion and prolonged uplift in the northern-most Hue Sub-basin. The inversion associated unconformity can be traced onshore where it separates a compositionally immature conglomerate from an overlying quartz conglomerate. Left-lateral transpression in the Hue Sub-basin coincides with that in the Song Hong Basin and other inversion events across SE Asia. This may have been caused by Australia-SE Asia collision restricting escape movement of Indochina away from the India-Asia collision zone.

Hơn 20 năm qua, công nghệ chụp cắt lớp được sử dụng trong ngành công nghiệp dầu khí để nghiên cứu đặc tính mẫu lõi và trực quan hóa dòng chảy lưu chất [1 - 8]. Trong đó, chụp cắt lớp định tính cung cấp thông tin về tính bất đồng nhất [9], sự thay đổi thạch học, khe nứt, hang hốc và mức độ xâm nhập của dung dịch khoan. Chụp cắt lớp định lượng ngoài các ứng dụng trên còn dùng để tính mật độ tổng (bulk density), độ rỗng và hiệu chuẩn đường cong địa vật lý giếng khoan. Bài báo giới thiệu phương pháp dự báo tính chất đá vỉa (như mật độ hạt, độ rỗng…) từ kết quả chụp cắt lớp theo phương pháp chụp cắt lớp 2 mức năng lượng (Dual-Energy CT Scanning - DECT) tại 140 kV và 80 kV. Kết quả chụp cắt lớp được so sánh với giá trị đường cong địa vật lý, cho thấy tiềm năng lớn trong việc xác định các tính chất vật lý của đá chứa cũng như chất lưu vỉa.

The lacking of the vertical mirror symmetry in Janus structures compared to their conventional metal monochalcogenides/dichalcogenides leads to their characteristic properties, which are predicted to play significant roles for various promising applications. In this framework, we systematically examine the structural, mechanical, electronic, and optical properties of the two-dimensional 2H Janus CrXO (X = S, Se, Te) monolayers by using first-principles calculation method based on density functional theory. The obtained results from optimization, phonon spectra, and elastic constants demonstrate that all three Janus monolayers present good structural and mechanical stabilities. The calculated elastic constants also indicate that the Janus CrTeO monolayer is much mechanically flexible than the other two monolayers due to its low Young's modulus value. The metallic behavior is observed at the ground state for the Janus CrSeO and CrTeO monolayers in both PBE and HSE06 levels. Meanwhile, the Janus CrSO monolayer exhibits a low indirect semiconducting characteristic. The bandgap of CrSO after the correction of HSE06 hybrid functional is the average value of its binary transition metal dichalcogenides. The broad absorption spectrum of CrSO reveals the wide activated range from the visible to near-ultraviolet region. Our findings not only present insight into the brand-new Janus CrXO monolayers but can also motivate experimental research for several applications in optoelectric and nanoelectromechanical devices.

Ultrafast, high sensitive, low cost photodetectors operating at room temperature sensitive from the deep-ultraviolet to mid-infrared region remain a significant challenge in optoelectronics. Achievements in traditional semiconductors using cryogenic operation and complicated growth processes prevent the cost-effective and practical application of broadband detectors. Alternative methods towards high-performance photodetectors, hybrid graphene-semiconductor colloidal quantum dots have been intensively explored. However, the operation of these photodetectors has been limited by the spectral bandwidth and response time. Here, we have demonstrated hybrid photodetectors operating from the deep-ultraviolet to the mid-infrared region with high sensitivity and ultrafast response by coupling graphene with a p-type semiconductor photosensitizer, nitrogen-doped Ta2O5 thin film. Photons with energy higher than the energy of the defect centers release holes from neutral acceptors. The holes are transferred into graphene, leaving behind ionized acceptors. Due to the advantage of two-dimensional heterostructure including homogeneous thickness, extending in a two-dimensional plane, large contact area between the N-Ta2O5 thin film and graphene, and the high mobility of carriers in graphene, holes are transferred rapidly to graphene and recirculated during the long lifetime of ionized acceptors. The photodetectors achieve a high photo-responsivity (up to 3.0 × 106 A W−1), ultrafast rise time (faster than 20 ns), and a specific detectivity (up to ∼2.2 × 1012 Jones). The work provides a method for achieving high-performance optoelectronics operating in the deep-ultraviolet to mid-infrared region.

Protein dynamics is strongly influenced by the surrounding environment and physiological conditions. Here we employ broadband megahertz-to-terahertz spectroscopy to explore the dynamics of water and myoglobin protein on an extended time scale from femto- to nanosecond. The dielectric spectra reveal several relaxations corresponding to the orientational polarization mechanism, including the dynamics of loosely bound, tightly bound, and bulk water, as well as collective vibrational modes of protein in an aqueous environment. The dynamics of loosely bound and bulk water follow non-Arrhenius behavior; however, the dynamics of water molecules in the tightly bound layer obeys the Arrhenius-type relation. Combining molecular simulations and effective-medium approximation, we have determined the number of water molecules in the tightly bound hydration layer and studied the dynamics of protein as a function of temperature. The results provide the important impact of water on the biochemical functions of proteins.

In this work, we systematically examine the electronic features and contact types of van der Waals heterostructures (vdWHs) combining single-layer boron phosphide (BP) and Janus Ga

Supersaturated solid solutions subjected to severe plastic deformation often exhibit decomposition of the solid solution, leading to a peculiar grain boundary phenomenon, the formation of few nanometer thin layer enriched in solute atoms along grain boundaries. Based on localized grain boundary sliding, this phenomenon can be explained by the formation of hydrostatic stress field, which induces up-hill diffusion in the solute atmosphere, resulting in solute atom accumulation along the stressed grain boundaries.

An ultrafine-grained (UFG) Al-4.8%Zn-1.2%Mg-0.14%Zr (wt%) alloy was processed by high pressure torsion (HPT) technique and then aged at 120 and 170 °C for 2 h. The changes in the microstructure due to this artificial aging were studied by X-ray diffraction and transmission electron microscopy. It was found that the HPT-processed alloy has a small grain size of about 200 nm and a high dislocation density of about 8 × 1014 m−2. The majority of precipitates after HPT are Guinier–Preston (GP) zones with a size of ~ 2 nm, and only a few large particles were formed at the grain boundaries. Annealing at 120 and 170 °C for 2 h resulted in the formation of stable MgZn2 precipitates from a part of the GP zones. It was found that for the higher temperature the fraction of the MgZn2 phase was larger and the dislocation density in the Al matrix was lower. The changes in the precipitates and the dislocation density due to aging were correlated to the hardness evolution. It was found that the majority of hardness reduction during aging was caused by the annihilation of dislocations and some grain growth at 170 °C. The aging effect on the microstructure and the hardness of the HPT-processed specimen was compared to that observed for the UFG sample processed by equal-channel angular pressing. It was revealed that in the HPT sample less secondary phase particles formed in the grain boundaries, and the higher amount of precipitates in the grain interiors resulted in a higher hardness even after aging.

We report the electrochemical performance and structural characteristics of porous nanostructured ceramic cathodes for thin-film solid oxide fuel cells (TF-SOFCs) based on yttria-stabilized zirconi...

We report electrical and thermal properties of perovskite-type Ba(Cu1/3Nb2/3)O3 (BCN) and Sr(Cu1/3Nb2/3)O3 (SCN). The BCN and SCN ceramics were synthesized by using the conventional solid state (CS...

In this study, with La0.8Sr0.2Cr0.5Fe0.5O3-δ (LSCrF) and Ce0.8Sm0.2O1.9 (SDC) taken as the electronic conducting phase and the oxide ion conductor, respectively, dual-phase composite ceramic membranes with or without 3 % (in mole) Y2O3 stable ZrO2 (3YSZ) support were prepared and tested as oxygen separation membranes. Then, the oxygen transmission performance was tested by the electrochemical method based on the limiting current. The results obtained with this method coincide with those acquired by means of gas chromatography. Furthermore, the dependences of oxygen permeation rate on oxygen partial pressure, temperature and ceramic membrane thickness were analyzed. When air was used as the sweeping gas on the porous 3YSZ supported SDC-LSCrF dual-phase membrane, the oxygen permeation rate can reach 0.73, 0.82, 0.90 and 0.97 mL cm−2 min−1 at 650, 700, 750 and 800 °C, respectively. Keywords: Dual-phase, Ceramic membranes, Oxygen permeation, Limiting current

The fast degradation rate and poor wear resistance of magnesium (Mg) alloys in physiological environments have limited their potential usage as next-generation biodegradable orthopedic implant materials. In this work, femtosecond laser shock peening (fs-LSP) was successfully applied to simultaneously improve the surface mechanical, corrosion, and tribocorrosion properties of WE43 Mg alloys in blood bank buffered saline solution at body temperature. Specifically, the treated surfaces of WE43 Mg alloys via fs-LSP with ultralow pulse energy were investigated under different power densities, confining mediums, and absorbent materials. It was found that the combination of a black tape and a quartz layer gave the optimum peening effect under a power density of 28 GW/cm

The capacity to navigate and identify individuals and other devices is becoming increasingly common and more essential in the era of the Internet of Things and the blooming of Wireless Sensor Networks. Outdoor positioning has been shown very well and is commonly used in everyday life thanks to the well-known GPS scheme. However, owing to the unique problems and distinctive requirements in the indoor environment, indoor positioning is still undergrowth and has attracted a lot of research and development in recent times. It can be said that finding an extensive solution like GPS in outdoor positioning will be nearly impossible. We need to evaluate the demands of the application and system so that we can determine the appropriate technology for the navigation system. Not only diversified in demands and technology, but the range of appliances engaged in the system also affects indoor positioning. This heterogeneity covers different kinds of operating systems and communication protocols. Besides, the problems recognised for indoor conditions such as the fading impact, signal attenuation, signal blocking, noise, and interference still cause the navigation system many problems. As a prospective technology candidate for indoor navigation devices, the Bluetooth Low Energy and iBeacon have appeared. The outstanding properties of Bluetooth Low Energy such as low consumption of energy, simplicity and elevated market penetration draw the attention of scientists. In this thesis, I develop an indoor positioning system using Bluetooth Low Energy technology. My scheme is based on a range-based technique that requires knowledge of beacons before positioning. Users with Bluetooth-enabled devices situated in the system region can be positioned by gathering RSSI signals. Then the information gathered will be filtered and processed through the proposed algorithm. Experiments demonstrate that my system achieves auspicious results with the error margin under half a metre for static devices. In addition, a mobile device sensor is used to measure inertial information. Applying pedestrian dead reckoning technique, direction and target position are estimated after that. Combining this outcome with my algorithms, the tracking results of my system achieved an error of about 0.2m.

Overpopulation, industrialization, and unregulated discharge result in the occurrence of the contaminants in water bodies, which calls for treatment technologies. Biological wastewater treatment is a technology where the main objective is to transform dissolved and particulate biodegradable constituents into acceptable end products. Biological treatment technologies are cost-effective, efficient, and many of them offer water reclamation qualities. Many pieces of research have been made to improve the removal of contaminants, trace compounds, operating conditions, and large-scale application. This chapter delivers an overview of biological wastewater treatment systems and highlights the future potential.

Experimental data show that the conventional Hall-Petch relationship cannot be maintained in its original form for metals having submicrometer structures. We now propose a dislocation model which modifies the Hall-Patch relationship to provide a uniform description of the grain size strengthening of submicron-structured face-centered cubic (f.c.c.) metals and solid solution alloys.

In aquatic environments, assessment of microplastic concentrations is increasing worldwide but environments from developing countries remain under-evaluated. Due to disparities of facilities, financial resources and human resources between countries, protocols of sampling, analysis and observations used in developed countries cannot be fully adapted in developing ones, and required specific adaptations. In Viet Nam, an adapted methodology was developed and commonly adopted by local researchers to implement a microplastic monitoring in sediments and surface waters of 21 environments (rivers, lakes, bays, beaches) of eight cities or provinces. Microplastic concentrations in surface waters varied from 0.35 to 2522 items m-3, with the lowest concentrations recorded in the bays and the highest in the rivers. Fibers dominated over fragments in most environments (from 47% to 97%). The microplastic concentrations were related to the anthropogenic pressure on the environment, pointing out the necessity in a near future to identify the local sources of microplastics.