bluuebunny/crossref_metadata_2025 huggingface dataset:
Variations around the presence and position of sulfur in sugar-derived cyclic monomers: influence on polymerisation thermodynamics, polymer sequence and thermal properties
Authors: Hardy Craig , Kociok-Köhn Gabriele , Buchard Antoine
Published: December 2022

The number and position of sulfur atoms in cyclic (thio)carbonate monomers fromd-glucal are varied, and their influence on polymerisability, polymer sequence and thermal properties is discussed.
Impregnating ultrafine FeS2 nanoparticles within hierarchical carbon tubes for advanced potassium-ion batteries
Authors: Zhang Zhuangzhuang , Qiao Yaru , Deng Qinghua , Jia Mengmin , Liu Dai-Huo , Dai Dongmei , Li Bao
Published: December 2022

FeS2-C@CTs is synthesized by a template-assisted vulcanization strategy, exhibiting high reversible capacity, excellent rate capability and stable cycling performance toward potassium-ion batteries.
Nickel-catalyzed tandem isomerization/anti-Markovnikov hydroarylation of unactivated internal alkenes with heteroarenes
Authors: Imran Sajid , Liu Yang , Li Yan , Shui Yu , Yan Chun-Hui , Sun Hong-Mei
Published: December 2022

A tandem isomerization/anti-Markovnikov hydroarylation of unactivated internal alkenes with heteroarenes was realized in a highly linear regioselective fashion using a catalytic system containing an NHC-based heteroleptic Ni(ii) complex and a base.
Bromine radical enhanced stoichiometric pyridylation of alkylarenes and diarylmethanes at room temperature
Authors: Wang Qiao-Lin , Huang Huawen , Mao Guojiang , Deng Guo-Jun
Published: December 2022

Sustainable photoredox catalysis with bromine radical-mediated hydrogen atom transfer enables stoichiometric pyridylation to synthesize a wide range of diarylmethanes and triarylmethanes in good to excellent yields.
Facile and scalable synthesis of un-doped, doped and co-doped graphene quantum dots: a comparative study on their impact for environmental applications
Authors: Suryawanshi Reena , Kurrey Ramsingh , Sahu Sushama , Ghosh Kallol K.
Published: December 2022

Heteroatom doped GQDs are new emerging organic materials show photoluminescence property. It creates defect in structure and enhance its properties, for bio sensing applications.
Effective reduction of nitric oxide over a core–shell Cu-SAPO-34@Fe-MOR zeolite catalyst
Authors: Ting-ting Xu , Gang-gang Li , Kai-hua Zheng , Xin-yan Zhang , Xin Zhang , Shao-qing Zhang
Published: December 2022

A core–shell catalyst of Cu-SAPO-34@Fe-MOR was successfully prepared through a silica-sol adhesion method with increased high-temperature activity, broadened reaction temperature window, and increased hydrothermal stability.
Phosphomolybdic acid hydrate encapsulated in MIL-53 (Fe): a novel heterogeneous heteropoly acid catalyst for ultrasound-assisted regioselective nitration of phenols
Authors: Nikseresht Ahmad , Bagherinia Rasoul , Mohammadi Masoud , Mehravar Reza
Published: December 2022

In this study, a heterogeneous catalyst, PMA@MIL-53 (Fe) (MIL ⇒ Matériaux de l'Institut Lavoisier), has been used to replace the usual mineral acids such as sulfuric acid.
Correction: Amyloid fibrillation of the glaucoma associated myocilin protein is inhibited by epicatechin gallate (ECG)
Authors: Sharma Ritika , Kumari Anchala , Kundu Bishwajit , Grover Abhinav
Published: December 2022

Correction for ‘Amyloid fibrillation of the glaucoma associated myocilin protein is inhibited by epicatechin gallate (ECG)’ by Ritika Sharma et al., RSC Adv., 2022, 12, 29469–29481, https://doi.org/10.1039/D2RA05061G.
A sensitive non-enzymatic electrochemical glucose sensor based on a ZnO/Co3O4/reduced graphene oxide nanocomposite
Authors: Hussein Beshir A. , Tsegaye Abebaw A. , Shifera Getabalew , M. Taddesse Abi
Published: December 2022

A novel sensitive and selective ZnO/Co3O4/rGO nanocomposite was fabricated using a hydrothermal method and used as a non-enzymatic electrochemical sensor for the detection of glucose.
Investigation of the impact of zeolite shaping and salt deposition on the characteristics and performance of composite thermochemical heat storage systems
Authors: Touloumet Quentin , Postole Georgeta , Massin Laurence , Lorentz Chantal , Auroux Aline
Published: December 2022

13X zeolite in powder displays higher storage performances and faster hydration kinetics than 13X in beads. Salt-doped zeolite composite in powder form presents lower pore blockage and higher storage performances than composites in beads.
A novel graphdiyne (CnH2n−2) synthesis strategy: design and application of an organic/inorganic conjugated system for photocatalytic hydrogen production
Authors: Wang Xuanpu , Li Teng , Wang Xiangyi , Jin Zhiliang
Published: December 2022

The GDY/CN-EDA composite photocatalyst was constructed according to the solvent-coordination molecular template mechanism. The synergistic interaction of EDA as a hole fixator and GDY as a hole inducer enhanced the H+reduction reaction.
High level Petri nets‐based proposal of an integrated intrusion detection and prevention mechanism in network controlled systems
Authors: Farah Khamsa , Chabir Karim , Abdelkrim Mohamed Naceur
Published: December 2022

The authors’ work deals with modelling with coloured Petri nets (CPN) of network controlled systems (NCS) and exposes a proposal of a sensor fault detection and prevention mechanism. In NCS, the network must be viewed as part of the system and not just a means of communication. For this, two issues must be considered. The first consists of adapting the control and diagnostic laws to the performance of the network. The second is to guarantee the performance of the system. Each control loop containing a network is vulnerable to faults and cyber attacks and malicious users can intercept and listen to data during transmission. For that reason, it is essential to protect transmitted data against unauthorized access and modification and to diagnose components. In this paper, the authors presented a model with CPN of a NCS, the authors proposed a sensor fault detection and correction mechanism, then the authors injected a sensor fault and the authors tested the effectiveness of the proposed mechanism in detecting that fault and correcting its influence. Simulation results proved the success of the preventive mechanism in overcoming the influence of the fault and returning to normal behaviour.
An online intelligent robust adaptive LSQR estimation method for LTI state space model
Authors: Hosseini Shahram , Navabi M. , Hajarian Masoud
Published: December 2022

Regarding the low accuracy and instability of common online methods for estimating dynamic models in the time domain, in the presence of uncertainty in system dynamics, sensor noise and environmental disturbances, this area is still open for further research. In this paper, a new estimation method is proposed based on a new online robust meta‐heuristic adaptive LSQR (ORALSQR) for simultaneous estimation of a multi input/output linear dynamic model and system state variables. This new adaptive LSQR algorithm is used to solve the output matrix equations of the least squares error problem. The presented algorithm, based on its iterative nature, searches the answer subspace by using a new meta‐heuristic logic. In addition, the algorithm solving steps and the search domain size in each iteration are intelligently determined by the method. In an identification maneuver, this method estimates the state variables using an estimated model in the Kalman filter, then estimates the model online for the next iteration using the state variables. In addition the stability proof of this method is presented. Numerical results show more accuracy and robustness of this method compared to the other methods mentioned in this paper which contain LS and RLS based estimation methods.
Stochastic expansion planning of transmission system and energy hubs in the presence of correlated uncertain variables
Authors: Allahvirdizadeh Yousef , Shayanfar Heidarali , Moghaddam Mohsen Parsa
Published: December 2022

Energy hubs (EHs), with interconnecting different energy carriers, technologies, and sectors, improve energy efficiency and enhance the flexibility of energy management. EHs can be an alternative to the upgradation of the transmission system infrastructures. Then, it is necessary to evaluate accurately the impact of integrating EHs across the power system on the expansion planning of the transmission system. This paper proposes an expansion planning of the transmission system and integrated EHs across the power system in deterministic and stochastic environments. In addition, the correlation among the uncertain variables may affect the expansion planning and scheduling decisions as well as the resulting costs. Therefore, the stochastic modelling of the proposed planning approach is developed considering the correlation among the uncertain variables. The uncertainties related to the generation of the renewable energy sources (RESs), energy demands, and electrical/thermal/cooling/gas price are addressed with a stochastic scenario‐based scheme. For this purpose, numerous scenarios are generated by implementing the well‐known Monte Carlo simulation (MCS) technique. Then the Cholesky decomposition technique combined with Nataf transformation is used to make the samples correlated. Next, the k‐means method as an efficient scheme of data clustering is used to reduce the initial scenarios to some limited ones.
Effect of organophilic group of coupling agent on the electrical performance of Boron Nitride/meta‐aramid composite paper
Authors: Ruan Haoou , Xie Qing , Song Jingxuan , Wang Shenghui , Chang Xiaobin , Xu Yuqin , Lü Fangcheng
Published: December 2022

Organophilic groups of coupling agents can be the key factor for the electrical performance of Boron Nitride (BN)/meta‐aramid composite paper. In this article, four types of triethoxy‐silane coupling agents with different organophilic groups, including mercapto‐propyl (MP), glycidylether‐propyl (GP), amino‐propyl (AP) and trideca‐fluoro‐octyl (TFO) were studied. The structural and electrical properties of modified papers were compared, and the molecular simulation was conducted to reveal the interface interaction of modified BN and aramid. The results show that AP, GP and MP follow the same mechanism, improving the electrical performance by modifying the interface stability and paper structure, and the ranks of improving effects are AP, MP and GP. While, TFO mainly relies on the fluorine components to implement the electrical reinforcement, which compensates for the shortcoming in the paper structure. By choosing TFO and filler content of 15 wt%, the optimal breakdown strength of the paper can be increased to 28.17 kV/mm, 1.8 times that of the paper doped with the hydroxylated BN.
Gesture recognition algorithm based on multi‐scale feature fusion in RGB‐D images
Authors: Sun Ying , Weng Yaoqing , Luo Bowen , Li Gongfa , Tao Bo , Jiang Du , Chen Disi
Published: December 2022

With the rapid development of sensor technology and artificial intelligence, the video gesture recognition technology under the background of big data makes human‐computer interaction more natural and flexible, bringing richer interactive experience to teaching, on‐board control, electronic games, etc. In order to perform robust recognition under the conditions of illumination change, background clutter, rapid movement, partial occlusion, an algorithm based on multi‐level feature fusion of two‐stream convolutional neural network is proposed, which includes three main steps. Firstly, the Kinect sensor obtains RGB‐D images to establish a gesture database. At the same time, data enhancement is performed on training and test sets. Then, a model of multi‐level feature fusion of two‐stream convolutional neural network is established and trained. Experiments result show that the proposed network model can robustly track and recognize gestures, and compared with the single‐channel model, the average detection accuracy is improved by 1.08%, and mean average precision (mAP) is improved by 3.56%. The average recognition rate of gestures under occlusion and different light intensity was 93.98%. Finally, in the ASL dataset, LaRED dataset, and 1‐miohand dataset, recognition accuracy shows satisfactory performances compared to the other method.
Parasites of Moroccan desert Coptodon guineensis (Pisces, Cichlidae): transition and resilience in a simplified hypersaline ecosystem
Authors: Louizi Halima , Hill-Spanik Kristina M. , Qninba Abdeljebbar , Connors Vincent A. , Belafhaili Amine , Agnèse Jean-Francois , Pariselle Antoine , de Buron Isaure
Published: December 2022

Sebkha Imlili (Atlantic Sahara) is a salt flat with over 160 permanent holes of hypersaline water generated in the Holocene and inhabited by euryhaline organisms that are considered to be relics of the past, including the cichlid fish Coptodon guineensis. We surveyed the fish parasites four times over one year, to i) identify the parasites, and ii) determine possible seasonality in infection patterns. Over 60% of the fish were infected by one to three helminths: an acanthocephalan in the intestine and two digenean metacercariae in the kidney, spleen, liver, muscle, and mesenteries. The acanthocephalan Acanthogyrus (Acanthosentis) cf. tilapiae was identified morphologically and molecularly; only one digenean (the heterophyid Pygidiopsis genata) could be identified molecularly. Both identified parasites were present throughout the sampling periods; the unidentified metacercariae were present only in summer and fall. Mean intensities, but not prevalence of infection by the acanthocephalan, reflected a biannual pattern of transmission. Infection accrued with fish size, possibly due to cannibalism. Because the water holes include only a few invertebrates, the intermediate hosts of these parasites can be inferred to be the gastropod Ecrobia ventrosa for the digeneans and either the copepod Cletocamtpus retrogressus or the ostracod Cyprideis torosa for the acanthocephalan. This ecosystem appears stable and provides a window into the past, as the acanthocephalan likely switched from freshwater tilapia to C. guineensis when the Sebkha formed. However, this is a vulnerable environment where the survival of these parasites depends on interactions maintained among only very few hosts.
Integrated approaches to COVID-19 emergency response in fragile, conflict-affected and vulnerable settings: a public health policy brief
Authors: Olu Olushayo Oluseun , Waya Joy Luba Lomole , Bankss Sandra , Maleghemi Sylvester , Guyo Argata Guracha
Published: December 2022

In the absence of fully effective measures to prevent and treat COVID-19, the limited access to and hesitancy about vaccines, the prolongation of the on-going pandemic is likely. This underscores the need to continue to respond and maintain preparedness, preferably using a more sustainable approach. A sustainable management is particularly important in fragile, conflict-affected and vulnerable countries of sub-Saharan Africa given several peculiar challenges. This Viewpoint proposes policy options to guide transitioning from current COVID-19 emergency response interventions to longer-term and more sustainable responses in such settings. In the long term, a shift in policy from a vertical to a more effective approach should integrate response coordination, surveillance, case management, risk communication and operational support, among other elements, for better results. We call on public health policymakers, partners and donors to support full implementation of these policy options in a holistic manner to encompass all emerging public health threats.
Turbulent characteristics and anisotropy in breaking surge waves: A numerical study
Authors: Venkateshwaran Akash , Li Zhuoran , Karimpour Shooka
Published: December 2022

Numerical simulations of breaking weak surge waves produced by the sudden removal of a gate were conducted to investigate turbulent characteristics generated by different mechanisms in the surge front. We conducted numerical studies using Large Eddy Simulation over a range of surge Froude numbers from 1.7 to 2.5, and a wide spectrum of tempo-spatial scales down to the Hinze scale was resolved. We established turbulent statistics by means of Favre-averaging where quantities were weighted by the instantaneous density. Our results demonstrated that the production of turbulent kinetic energy is mainly sourced at the toe, where the shear layer originates. Furthermore, the decomposition of production elements illustrated that the shearing action is the principal driver in the entire surge front. Herein, we also conducted intricate anisotropy analyses, including establishing characteristic shape maps by pointwise eigendecomposition of Reynolds stress tensors. Near the toe at the core of the mixing layer, prolate structures were evident that are mainly stretched in the streamwise direction. Moving from the mixing layer toward the free surface, however, the structure changes to a combination of prolate and oblate features, where the smallest principal stress is nearly in the spanwise direction. In a snapshot, our results illustrate a clear transition in anisotropy from the recirculating region to the mixing layer.
Strategies for reducing airborne disease transmission during breathing using a portable air cleaner in a classroom
Authors: Romero-Flores Michel , López-Guajardo Enrique A. , Delgado-Gutiérrez Arturo , Montesinos-Castellanos Alejandro
Published: December 2022

In this work, computational fluid dynamics and a factorial study were conducted to analyze the air cleaning capabilities of a portable air cleaner (PAC) in a closed room with 10 thermal manikins and two air distribution system (ADS) speeds. The particles emitted by the breathing of the manikins (1250 particles/manikin) were tracked for 50 min, and their trajectories were analyzed. Factorial analysis was performed to investigate the relevance of the variables studied and their interactions. The results showed that the PAC–ADS configuration was a major factor affecting the transference of particles. A total risk index was defined (RItotal) to identify the total percentage of particles transferred between the occupants in each case. The best case had half the transference of particles compared with the worst case (2.03% vs 3.98%, respectively). Moreover, locating the PAC with a downward flow direction near the emitter significantly reduced the transference of its particles. However, it increased the number of particles that this emitter received from others in the classroom. The factorial analysis showed that PAC speed contributed the most to the transference of particles (24%) and particles filtered by the PAC (25.8%). In comparison, PAC position had the highest impact on particles remaining in the breathable zone of the room (13.7%) and particles leaving the system through the ADS (23.3%). Overall, a configuration in which the PAC is at the center of the classroom with a downward flow was shown to be the most efficient for reducing the spread of airborne diseases.
Ultra-sensitive terahertz sensing based on Rayleigh anomaly in hyperbolic metamaterial gratings
Authors: Li Guangyuan , Yang Xiuhua
Published: December 2022

Terahertz sensors are promising for biomedical, environmental and security applications. Challenges in terahertz sensing have been the limited sensitivity and small figure of merit (FOM). Here we propose an ultra-sensitive terahertz sensing platform based on the Rayleigh anomaly (RA) in hyperbolic metamaterial gratings, which are composed of periodic slits patterned in paired metal-dielectric multilayers. Simulation results show that, under normal incidence with transverse-magnetic polarization and designed with proper parameters, the proposed structure has a super-high quality factor of 516, an ultra-high sensitivity of 1.56 THz RIU−1 (or

9.06
×

10
4

 nm RIU−1), and extremely large FOM of 355 RIU−1 at frequency of 2.272 THz, corresponding to a large normalized sensitivity of 0.69 RIU−1. By comparing with other multilayered gratings, we attribute this exceptionally high sensing performance to the strong local field enhancement over an extremely large area in the sensing region at the RA frequency, which is found to be unique for hyperbolic metamaterial gratings. We further show that the resonance frequency decreases linearly with the grating period, following the RA equation, whereas the large normalized sensitivity keeps constant. We expect this work provides a novel strategy to design extremely sensitive sensors in terahertz as well as other frequency regimes.
A potential well model for host-guest chemistry in double-network hydrogels toward mechanochemical coupling and toughening
Authors: Xing Ziyu , Lu Haibao , Lau Denvid , Fu Yong-Qing
Published: December 2022

Different from conventional single-network hydrogels, double-network (DN) hydrogels have attracted great research interest due to their ultra-high toughness; however, the working principles behind their complex mechanochemical coupling have not been fully understood. In this study, an extended potential well model is formulated to investigate the host-guest chemistry and the free-energy trap effect, coupled in DN hydrogels undergoing mechanochemical toughening. According to the Morse potential and mean field model, the newly established potential well model can describe the coupled binding of the host brittle network and guest ductile network in the DN hydrogels. A free-energy equation is further proposed to describe the working principles of the mechanochemical coupling and toughening mechanisms using the depth, width, and trap number of potential wells, which determine the barrier energy of the host brittle network, the mesh size of guest ductile network, and the mechanochemical host-guest interactions of these two networks, respectively. Finally, the effectiveness of the proposed model is verified using finite-element analysis (FEA) and experimental results of various DN hydrogels reported in the literature. Using the potential well model, which has host-guest chemistry from both brittle and ductile networks, this study clarifies the linking of mechanochemical coupling and toughening mechanisms in DN hyrdogels.
Guided ultrasonic waves propagation imaging: a review
Authors: Chia Chen Ciang , Lee Shi Yn , Harmin Mohammad Yazdi , Choi Yunshil , Lee Jung-Ryul
Published: December 2022

This article presents a comprehensive review of the laser-based guided ultrasonic waves propagation imaging (G-UPI) system and respective signal/data processing methods related to the nondestructive testing and evaluation of thin-walled structures. The primary goal of this study is to review and recognize various processing methods, explain the working principles of the most influential methods, and highlight outstanding capabilities. In addition, the suitability of the methods for multiple types of damage and defect in various materials and structures are presented. At the same time, success stories of difficult-to-inspect cases are highlighted. Its secondary goal is to compare and discuss the merits and demerits of the laser-scanning part of the system for ultrasound generation and acquisition to provide a guideline for scanning scheme or hardware selection. Finally, the potential challenges and prospects of the G-UPI are discussed. It is expected that this review would serve as an entrance key for newcomers and a reference point for researchers to explore the opportunities for further improvement in the laser ultrasound-based evaluation of critical engineering structures.
Optimized electromagnetic wave absorption of α-Fe2O3@MoS2 nanocomposites with core–shell structure
Authors: Wu Mei , Wang Hongchang , Liang Xiaohui , Wang Dunhui
Published: December 2022

Core–shell structures and interfacial polarization are of great significance to meet the diversified requirements of microwave attenuation. Herein, α-Fe2O3@MoS2 nanocomposites are fabricated via a simple two-step hydrothermal process, in which MoS2 nanosheets as the shell are self-assembled and α-Fe2O3 microdrums are used as the core to constitute a special flower-like morphology with core–shell structure. This structure can provide more interface contact to achieve strong interfacial polarization and possibly offer more multiple reflection and scattering of electromagnetic waves. Furthermore, the microwave dissipation performances of α-Fe2O3@MoS2 nanocomposites can be significantly improved through construction of core–shell structure and flower-like morphology, controlling the content of α-Fe2O3 microdrums and adjusting the filler loading ratios. This work proves that the as-synthesized nanocomposites achieve excellent effective absorption bandwidth and outstanding electromagnetic wave absorption capabilities due to their special interfaces, core–shell structures and good impedance matching conditions. Therefore, α-Fe2O3@MoS2 nanocomposites are expected to be a novel and desirable candidate for high-performance electromagnetic wave absorbers.
Graphene enhanced flexible piezoelectric transducers for dynamic strain measurement: from material preparation to application
Authors: He Jingjing , Fang Ziwei , Gao Chenjun , Zhang Wenxi , Guan Xuefei , Lin Jing
Published: December 2022

In this study, graphene particles are introduced to the lead magnesium niobate-lead titanate and polyvinylidene fluoride (PVDF) to form a flexible ternary composite. The graphene concentration is rigorously designed and morphologically optimized, warranting good piezoelectric and dielectric properties. The piezoelectric and dielectric performances are greatly increased compared with the pure PVDF films. Then a theoretical model is formulated to quantitatively interpret the graphene effect on the permittivity performance and to provide guidelines for the optimization of graphene volume fraction. Moreover, a simple and cost-effective technique is designed to package the composite film as a large-area, lightweight and flexible transducer. Several confirmatory experiments and a proof-of-concept test are performed based on the proposed flexible piezoelectric transducer to validate the capability of the dynamic strain sensing. By comparing with the results from conventional strain gauges and ceramic piezoelectric wafers, it is verified that the proposed flexible transducer has proven responsivity and precision in responding to quasi-static strain, medium-frequency vibration, and ultrasound. The great potential of the developed transducer for a wide range of applications including structural health monitoring and human motion detection has been demonstrated.
A battery-free music-driven humidity sensor for intelligent wearable sensing system in smart diaper
Authors: Peng Yifeng , Long Zhihe , Liang Shan , Zhong Tianyan , Chen Meihua , Xing Lili , Xue Xinyu
Published: December 2022

A potential intelligent multifunctional diaper with the integration of flexible sensors and data processing/transmitting units may have the functions of monitoring the urination of babies, detecting the physiological parameters and transmitting the information to the mobile terminal of their parents. Here, we present a battery-free music-driven humidity sensor for an intelligent wearable sensing system in a smart diaper. The working mechanism is based on the coupling of the triboelectric effect and the humidity-sensing process. Driven by baby-acceptable musical sound, the two layers of the device vibrate (resonance effect), and the triboelectric effect generates an electrical output. The output decreases with the increasing humidity, acting as both a power source and humidity-sensing signal. The sensor can be embedded in a diaper to monitor the urination of the baby, and a wireless transmitter is integrated in the system to upload the information. The present results can promote the development of the next generation of self-powered active sensors and expand the scope of battery-free sensing systems.
Rotational mirror–mirror entanglement via dissipative atomic reservoir in a double-Laguerre–Gaussian-cavity system
Authors: Wang Fei , Shen Kang , Xu Jun
Published: December 2022

We propose a new scheme to prepare macroscopic entanglement between two rotating mirrors using dissipative atomic reservoir in a double-Laguerre–Gaussian-cavity system. The two-level atomic system driven by a strong field, acts as a single pathway of Bogoliubov dissipation to push the two original cavity modes into the desirable entangled state under the near-resonant conditions. Successively, the photon–photon entanglement can be transferred to mirror–mirror entanglement through the exchange of orbital angular momentum. In essence, the macroscopic entanglement is originated from the dissipative atomic reservoir rather than the radiation torque, thereby it is usually robust against environmental noises. The present scheme provides a feasible way to realize stable entanglement between spatially separated mirrors with high capacity, which may find potential applications in remote quantum communications.
Potential of utilizing immiscible polymer blends as porous materials
Authors: Alsewailem Fares D , Alabbad Eman A
Published: December 2022

The goal of this research was to examine the ability of commodity polymer blends to be used as low cost porous materials as a replacement for costly porous materials such as activated carbon. Three blend systems were prepared based on high-density polyethylene (HDPE) and polystyrene (PS) as major phases and polyvinyl alcohol (PVA) and PS as minor phases. All the blend systems were prepared at 10 wt% of the minor phase with melt blending method using conventional polymer processing equipment. In order to enhance the porosity of the prepared blends, appropriate staining agent was applied to partially remove the minor phase out of the prepared blend samples. PV was stained with water while PS was stained with ethyl acetate (EAC). It was seen that, by the result of this study, the satined blend system of HDPE/PVA showed best surface and mechanical properties. Amount of adsorbed nitrogen was above 18 cm3 g−1 at a relative pressure of one for the stained HDPE/PVA and PS/PVA. This may introduce a cost effective polymer blend material that may be used for moisture or gas storage.
Conservation laws of optical Bloch equations for the tripod scheme - contribution of double dark-state
Authors: Dimitrijević Jelena , Jelenković Branislav M , Arsenović Dušan
Published: December 2022

Results are presented for the conservation laws (CLs) of the optical Bloch equations (OBEs) for the 4-level tripod atomic scheme under the action of three laser fields. CLs are constructed for OBEs that include the spontaneous emission, collisional broadening and time of flight relaxation, and also without these effects, i.e. for the Liouville von Neumann equation (LNE). We used the direct method to construct CLs as the linear combinations of the density matrix elements and their products. These CLs were in turn used to obtain another set of CLs that explicitly depend on time and stand with relaxation due to the time of flight in OBEs. We also constructed CLs for OBEs representing special case of the tripod system that supports the coherent population trapping (CPT), the phenomenon characterized by the ‘dark-state’. Tripod scheme has two dark-states with the same Hamiltonian eigenvalue. As we explain, this peculiarity of tripod scheme contributes to additional CLs of both LNE and OBEs with all relaxation and decoherence effects included, when CPT is present.
Three-dimensional fourier imaging of thousands of individual solid-state quantum bits – a tool for spin-based quantum technology
Authors: Artzi Yaron , Zgadzai Oleg , Solomon Benjamin , Blank Aharon
Published: December 2022

Nitrogen vacancies in diamond (NVs) are frequently considered as possible candidates to constitute the building blocks of spin-based quantum computers. The main caveats to this approach are the lack of a reliable process to accurately place many NVs in close proximity to each other (∼10–20 nm) to enable an adequate spin-spin interaction; and the inability to read out and selectively manipulate the quantum states of many such closely spaced NVs. A possible approach to overcome these issues includes the following: (i) making use of a diamond dense with NVs in random (‘as-produced’) 3D positions; (ii) mapping out their individual locations at high spatial resolution (in 3D); (iii) employing techniques for selective spin manipulation based on the mapped 3D locations of the NVs; and (iv) making use of imaging techniques to read out the quantum state of the NVs. Within this grand vision, we present here a tool that can support this scheme—namely, an approach to the efficient high accuracy 3D mapping of many thousands of individual NVs in a diamond via magnetic resonance imaging (MRI). In the present work, the NVs’ spacings and the corresponding imaging resolution are in the submicron-scale, but the same approach can be scaled down to support a resolution lower than 10 nm in diamonds with dense NVs, as is required for practical quantum computing applications.
Preparation of lead hexaferrite filled PVA- PVP nanocomposite and a study of its structural features, optical and dielectric properties
Authors: Abomostafa H M , Abouhaswa A S , Rabiea E A
Published: December 2022

Polymer blend films based on PVA-PVP filled with PbFe12O19 hexa-ferrites nanoparticles were created by solution casting technique. XRD, HRTEM, FESEM, FTIR, UV–vis spectroscopy and Broad-band dielectric spectroscopy were used to examine the properties of the prepared polymer composite films. X-ray diffraction pattern of the powder confirmed the formation of PbFe12O19 with hexagonal phase and that for the films confirmed the incorporation of the PbFe12O19 nanoparticles in the PVA-PVP blends. HRTEM confirms the formation of hexagonal nanoparticles with average size ranged from 7 nm to 21 nm. Field emission scanning electron microscopy (FESEM) studied the morphology of the nanocomposite films. There are noticeable variations in FT-IR spectra that confirm the incorporation of PbFe12O19, NPs in PVA-PVP blend. The absorbance was found to increase with red shift in the ultraviolet-visible region while the transmittance decreases with increasing PbFe12O19, nanoparticles. By incorporating, PbFe12O19 the direct optical gap and indirect optical gap gradually decreased from 5.20 eV to 4.44 eV and 4.97 eV to 4.34 eV, respectively while the Urbach energy increases from 0.274 eV to 0.678 eV. According to the Wemple-Didomenico single oscillator model, the optical dispersion parameters have been examined and are found to be strongly affected by PbFe12O19, loading. Additionally, the nanocomposite film containing 7.5% PbFe12O19, demonstrated outstanding optical shielding. The complex dielectric constant (ε*), complex electric modulus (M*) and electrical conductivity, of NCPs materials have been studied with the frequency changing from 0.1 Hz to 10 MHz. The real permittivity (

ε
′

) of PVA-PVP blend polymer film increased while the real electric modulus (M′) is found to decrease by the incorporation of PbFe12O19, nanoparticles up to 2.5 wt.% and the imaginary component of permittivity follows the same pattern of

ε
′
.

The examined nanocomposite films show promise for flexible optoelectronics, photosensors, optical shielding and nano-dielectric materials.
Effects of surface vacancy-adatom pair formation on PFC tungsten surface morphological response
Authors: Chen Chao-Shou , Dasgupta Dwaipayan , Weerasinghe Asanka , Hammond Karl D. , Wirth Brian D. , Maroudas Dimitrios
Published: December 2022

We report a simulation study of the effect of He-irradiation-induced surface vacancy-adatom pair formation on the surface morphological evolution of plasma-facing component (PFC) tungsten and examine a number of factors that impact such evolution. Our analysis is based on self-consistent dynamical simulations according to an atomistically-informed, continuum-scale surface evolution model that has been developed following a hierarchical multiscale modeling strategy and can access the spatiotemporal scales of relevance to fuzz formation. The model accounts for the flux of surface adatoms generated as a result of the surface vacancy-adatom pair formation effect upon He implantation, which contributes to the anisotropic growth of surface nanostructural features due to the different rates of adatom diffusion along and across step edges of islands on the tungsten surface. We have carried out atomic-scale computations of optimal diffusion pathways along and across island step edges on the W(110) surface and calculated Ehrlich–Schwoebel (ES) barriers in adatom diffusion along and across such step edges. This aspect of surface adatom diffusion contributes to anisotropic surface atomic fluxes, terrace and step diffusive currents, and has been incorporated into our PFC surface evolution model, which predicts the formation of preferentially aligned nanoridge stripe patterns on the PFC surface. We establish that these anisotropic diffusive currents accelerate nanotendril growth on the PFC surface and the onset of surface nanostructure pattern formation. We also explore systematically the dependence of the PFC surface morphological response on the surface temperature and He ion incident flux, characterize in detail the resulting surface topographies and growth kinetics, and compare the predicted surface morphologies with experimental observations. Our simulation predictions for the emerging surface nanostructure patterns under certain plasma exposure conditions are consistent with experimental findings in the literature.
Compatibility of large ELM control and stable partial detachment with neon/argon seeding in EAST
Authors: Li K. , Lin X. , Yang Z. , Yang Q. , Xu G. , Meng L. , Wang Y. , Lan H. , Zhang B. , Xu L. , Wu K. , He T. , Xu J. , Wu J. , Ding F. , Duan Y. , Mao S. , Zang Q. , Zhang L. , Zhang T. , Wang F. , Wang L. , Luo G.-N.
Published: December 2022

It is necessary to achieve simultaneous exhaust of excessive transient and steady-state heat fluxes on the divertor target for the divertor protection in the future fusion reactors. The sustained large ELM control and stable partial detachment have been achieved concurrently with argon (Ar) or neon (Ne) seeding in EAST. With Ne seeding, the large ELMs with frequency f
ELM ∼ 100 Hz disappear and a stable ELM-free state with H
98,y2 > 1 is maintained. Meanwhile, the electron temperature T
et around the lower outer strike point decreases from more than 70 eV during the large ELM burst to less than 5 eV in the stable ELM-free phase. In addition, a slight improvement of plasma confinement is observed in the partially detached state, mainly attributed to the increased electron density n
e and ion temperature T
i in the core region. In the pedestal region, the density gradient and the electron temperature show subtle variation. The effective charge number Z
eff increases significantly after Ne seeding, leading to a decrease in the edge bootstrap current and the pedestal pressure gradient, and thus the stabilization of ELMs. With Ar seeding, the large ELMs are also suppressed at first, but soon transit to type-III ELMs with a high f
ELM ∼ 1 kHz, highly correlated with the energy confinement degradation. The steady-state and transient heat fluxes on the divertor can be both well reduced with Ar/Ne seeding in EAST.
10 years of Aichi Synchrotron Radiation Center Impact on industrial and academic research and developments
Authors: Kunieda H. , Takashima Y. , Okajima T. , Takeda Y.
Published: December 2022

The synchrotron light source with the electron energy of 1.2 GeV is operated by Aichi Synchrotron Radiation Centre (AichiSR) in Aichi prefecture, Japan. The light has been offered to industrial and academic users since March 2013 in the top-up operation mode to maintain a constant current of 300 mA. This facility was established by Aichi prefecture, universities, and industries with support of government. Major purpose of the light source is to support research and development activities of industries and academia mostly in the area, which is the heart land of manufacturing of Japan. This paper describes evolution of the beamlines and recent research results and their impact to the society.
Permanent Magnet phase shifters for FLASH2020+ FEL
Authors: N’gotta P , Vagin P , Tischer M
Published: December 2022

The development of a simple and compact permanent magnet (PM) phase shifter is presented in this paper. The design is based on four PM blocks per girder (8 PM blocks in total), and uses only one type PM block with horizontal magnetization and 15mm length. The magnetic field provides a net zero and second field integral and a phase integral of 2 · 10–6
T
2
m
3 for 60mm overall magnet length. The study of the numerical model with Radia shows that this design is mainly sensitive to angular magnetization errors. The correction strategy is based on pairing the PM blocks in order to cancel the sum of magnetization angle error, and the remaining magnetic field error is corrected with a stack of magic fingers located around the magnet. Finally, a prototype was built, and the magnetic measurements results are presented here.
Development of an APPLE-III undulator for FLASH-2
Authors: Tischer M , Bienert H , Götze K , Meissner D , Neumann P , N’Gotta P , Ramm T , Schöps A , Talkovski P , Telawane S , Vagin P
Published: December 2022

The use of circularly polarized soft X-rays at the FLASH-FEL at DESY will be a very versatile tool for investigation of dynamic properties in nanomagnetism. For that purpose, the development of a variable polarization undulator was started to provide an afterburner downstream of the FLASH2 SASE undulators. It will serve to produce circularly polarized light with a wavelength of 1.33 nm to 1.77 nm (890 eV - 700 eV) to investigate the L-edges of Fe, Co, and Ni. This wavelength range together with the future maximum beam energy of 1.35 GeV at FLASH leaves only a small and ambitious parameter window for the undulator if a noteworthy tunability range shall be provided.

We report on design and development of an APPLE-III undulator with 17.5 mm period length operating at a minimum magnetic gap of 8 mm which will make use of a magnetic force compensation scheme. A short prototype has been built to verify and iterate both the mechanical and magnetic concept. Details on the keeper design, results of the magnetic measurements and the tuning concept will be presented.
The vacuum chamber for the APPLE-X undulators at the European XFEL
Authors: La Civita D. , Casalbuoni S. , Karabekyan S. , Planas M. , Sinn H. , Wohlenberg T. , Wünschel M. , Yang F.
Published: December 2022

Thanks to the installation of four APPLE X helical undulators, the SASE3 soft X-ray beamline at European XFEL will provide to the experimental stations the polarization control of the X-rays. The helical undulators are located downstream with respect to the already existing planar undulators. The design of the magnetic active parts and of the helical undulator support structure requires a new design of the vacuum chamber and its alignment system. This contribution describes the mechanical design, production process, UHV qualification process and alignment of the vacuum chamber.
X-ray scattering at beamline BL2 of DELTA: Studies of lysozyme-lysozyme interaction in heavy water and structure formation in 1-hexanol
Authors: Dargasz M , Bolle J , Faulstich A , Schneider E , Kowalski M , Sternemann C , Savelkouls J , Murphy B , Paulus M
Published: December 2022

The experimental station of the bending magnet beamline BL2 of the Dortmund Synchrotron Radiation Source DELTA has been reconstructed in order to enable small-angle X-ray scattering and wide-angle scattering studies with monochromatic beam. By using a multilayer monochromator with a bandwidth of 1.5%, it is possible to reach a photon energy of 12 keV at sufficiently high photon fluxes. The beamline layout is described and the experimental capabilities are discussed by giving two examples of typical experiments: (i) A dense lysozyme solution is studied using small-angle X-ray scattering in order to reveal to influence of pressure on the protein-protein interaction with heavy water as solvent. (ii) The dependency of the hydrogen-bond mediated structure formation on temperature and pressure is investigated in liquid 1-hexanol by wide-angle X-ray scattering.
A new beamline for hard X-ray tomographic microscopy at the Spanish Synchrotron ALBA
Authors: Mittone Alberto , Ribó Llibert , Patera Alessandra , Campmany Josep , Colldelram Carles , Nicolás Josep
Published: December 2022

The BL31-FaXToR is a new beamline currently under construction at the third generation synchrotron facility ALBA, dedicated to hard x-ray micro-tomography. The beamline will provide the opportunity to perform 3D imaging within sub-seconds time resolution, working under mono- or white-beam conditions. A dual detection system is foreseen at the top of an innovative end-station design in order to perform fast imaging with a multi-scale approach. In this paper, we provide an overview of the new beamline design and of the expected performances. Raytracing and phase-contrast imaging simulations have been used to optimize the optical design. The beamline will be fed by a 2.5T multipole wiggler with a critical energy of 14.7 keV. A double multilayer monochromator (DMM) covers an energy range between 8 to 50 keV with a bandwidth up to 3.5%. The DMM crystals can be shifted out of the beam path to operate in filtered white beam modality with higher energies spanning from 30 to 70 keV. Multiple filtering configurations will be used to optimize the spectra according to the specific experimental settings. The beamline will serve different scientific communities, including material science, biomedical, paleontology, earth science, cultural heritage etc. FaXToR is expected to start user operations by the beginning of 2024.
A combination of soft X-ray and laser light sources offer 3D high content information on the native state of the cellular environment
Authors: Okolo Chidinma A , Fish Thomas M , Nahas Kamal L , Jadhav Archana C , Vyas Nina , Taylor Adam , Harkiolaki Maria
Published: December 2022

Beamline B24 is a life sciences correlative cryo-imaging beamline at Diamond Light Source. B24 uses a combination of conventional and super-resolution visible-light fluorescence microscopy and soft X-ray tomography (cryoSXT) to provide 3D imaging of the cellular landscape at a resolution up to 25 nm in cryo-preserved biological samples up to 12 μm thick. B24 offers user-friendly, semi-automated 3D correlative cryo-imaging through an integrated platform of methods that encompass (a) sample preparation and evaluation, (b) data collection and processing and (c) data analysis and correlation. CryoSXT fills the current resolution gap between fluorescence and electron microscopy while cryo-structured illumination microscopy provides the additional dimension of chemical localization within the same cellular ultrastructure captured by cryoSXT. Beamline instruments can be accessed biannually by academics and industry globally through peer-reviewed standard and rapid access proposal processes. The B24 user base is primarily academic research groups studying cell function and cytopathology in biological systems ranging from viruses and algae to mammalian cells and proto-tissue complexes. Future work will consolidate development efforts and experiences gained thus far to enable high-throughput data collection. Special emphasis is placed on the delivery of other integrated advanced imaging methods such as X-ray absorption near-edge spectroscopy and phase contrast.