bluuebunny/crossref_metadata_2025 huggingface dataset:
Study of Structural and Optical Properties of Titanate Nanotubes with Erbium under Heat Treatment in Different Atmospheres
Authors: Rodrigues Gelson L. C. , Oliveira Tainara G. de , Gusmão Suziete B. S. , Ferreira Odair P. , Vasconcelos Thiago L. , Guerra Yuset , Milani Raquel , Peña-Garcia Ramón , Viana Bartolomeu C.
Published: February 2023

Titanate nanotubes were synthesized and subjected to an ion exchange reaction with erbium salt aqueous solution to obtain titanate nanotubes exchanged with erbium (3+) ions. In order to evaluate the effects of the thermal treatment atmosphere on the structural and optical properties of erbium titanate nanotubes, we subjected them to heat treatment in air and argon atmospheres. For comparison, titanate nanotubes were also treated in the same conditions. A complete structural and optical characterizations of the samples was performed. The characterizations evidenced the preservation of the morphology with the presence of phases of erbium oxides decorating the surface of the nanotubes. Variations in the dimensions of the samples (diameter and interlamellar space) were promoted by the replacement of Na+ by Er3+ and the thermal treatment in different atmospheres. In addition, the optical properties were investigated by UV–Vis absorption spectroscopy and photoluminescence spectroscopy. The results revealed that the band gap of the samples depends on the variation of diameter and sodium content caused by ion exchange and thermal treatment. Furthermore, the luminescence strongly depended on vacancies, evidenced mainly by the calcined erbium titanate nanotubes in argon atmosphere. The presence of these vacancies was confirmed by the determination of Urbach energy. The results suggest the use of thermal treated erbium titanate nanotubes in argon atmosphere in optoelectronics and photonics applications, such as photoluminescent devices, displays, and lasers.
Visual–Tactile Perception of Biobased Composites
Authors: Thundathil Manu , Nazmi Ali Reza , Shahri Bahareh , Emerson Nick , Müssig Jörg , Huber Tim
Published: February 2023

Biobased composites offer unique properties in the context of sustainable material production as well as end-of-life disposal, which places them as viable alternatives to fossil-fuel-based materials. However, the large-scale application of these materials in product design is hindered by their perceptual handicaps and understanding the mechanism of biobased composite perception, and its constituents could pave the way to creating commercially successful biobased composites. This study examines the role of bimodal (visual and tactile) sensory evaluation in the formation of biobased composite perception through the Semantic Differential method. It is observed that the biobased composites could be grouped into different clusters based on the dominance and interplay of various senses in perception forming. Attributes such as Natural, Beautiful, and Valuable are seen to correlate with each other positively and are influenced by both visual and tactile characteristics of the biobased composites. Attributes such as Complex, Interesting, and Unusual are also positively correlated but dominated by visual stimuli. The perceptual relationships and components of beauty, naturality, and value and their constituent attributes are identified, along with the visual and tactile characteristics that influence these assessments. Material design leveraging these biobased composite characteristics could lead to the creation of sustainable materials that would be more attractive to designers and consumers.
Effect of Isothermal Annealing on Sn Whisker Growth Behavior of Sn0.7Cu0.05Ni Solder Joint
Authors: Hashim Aimi Noorliyana , Salleh Mohd Arif Anuar Mohd , Ramli Muhammad Mahyiddin , Abdullah Mohd Mustafa Al Bakri , Sandu Andrei Victor , Vizureanu Petrica , Sandu Ioan Gabriel
Published: February 2023

This paper presents an assessment of the effect of isothermal annealing of Sn whisker growth behavior on the surface of Sn0.7Cu0.05Ni solder joints using the hot-dip soldering technique. Sn0.7Cu and Sn0.7Cu0.05Ni solder joints with a similar solder coating thickness was aged up to 600 h in room temperature and annealed under 50 °C and 105 °C conditions. Through the observations, the significant outcome was the suppressing effect of Sn0.7Cu0.05Ni on Sn whisker growth in terms of density and length reduction. The fast atomic diffusion of isothermal annealing consequently reduced the stress gradient of Sn whisker growth on the Sn0.7Cu0.05Ni solder joint. It was also established that the smaller (Cu,Ni)6Sn5 grain size and stability characteristic of hexagonal η-Cu6Sn5 considerably contribute to the residual stress diminished in the (Cu,Ni)6Sn5 IMC interfacial layer and are able to suppress the growth of Sn whiskers on the Sn0.7Cu0.05Ni solder joint. The findings of this study provide environmental acceptance with the aim of suppressing Sn whisker growth and upsurging the reliability of the Sn0.7Cu0.05Ni solder joint at the electronic-device-operation temperature.
Numerical Study of Flow Boiling of ADN-Based Liquid Propellant in a Capillary
Authors: Liu Xuhui , Su Gaoshi , Yao Zhaopu , Yan Zhuan , Yu Yusong
Published: February 2023

During the operation of ADN (ammonium dinitramide, (NH4+N(NO2)2−))-based thrusters, the ADN-based liquid propellant, a non-toxic green energetic material, tends to flow boil in the capillary tube due to heat transfer from the wall. A three-dimensional transient numerical simulation of the flow boiling of ADN-based liquid propellant in the capillary tube was carried out using the VOF (Volume of Fluid) coupled Lee model. The flow-solid temperature and the gas–liquid two-phase distribution and the wall heat flux at different heat reflux temperatures were analyzed. The results show that the magnitude of the mass transfer coefficient of the Lee model significantly influences the gas–liquid distribution in the capillary tube. The total bubble volume increased from 0 mm3 to 957.4 mm3 when the heat reflux temperature was increased from 400 K to 800 K. The bubble formation position moves upwards along the inner wall surface of the capillary tube. Increasing the heat reflux temperature intensifies the boiling phenomenon. When the outlet temperature exceeded 700 K, the transient liquid mass flow rate in the capillary tube was already reduced by more than 50%. The results of the study can be used as a reference for the design of ADN-based thruster.
A New Polymorphic Comprehensive Model for COVID-19 Transition Cycle Dynamics with Extended Feed Streams to Symptomatic and Asymptomatic Infections
Authors: Al-Hadeethi Yas , El Ramley Intesar F. , Mohammed Hiba , Barasheed Abeer Z.
Published: February 2023

This work presents a new polymorphic, reusable, and comprehensive mathematical model for COVID-19 epidemic transition cycle dynamics. This model has the following characteristics: (1) The core SEIR model includes asymptomatic and symptomatic infections; (2) the symptomatic infection is a multi-variant; (3) the recovery stage provides a partial feed to the symptomatic infection; and (4) the symptomatic and asymptomatic stages have additional feed streams from the protected stage. The proposed formalisation template is a canonical way to achieve different models for the underlying health control environment. This template approach endows the model with polymorphic and reusable capability across different scenarios. To verify the model’s reliability and validity, this work utilised two sets of initial conditions: date range and COVID-19 data for Canada and Saudi Arabia.
On Designing of Bayesian Shewhart-Type Control Charts for Maxwell Distributed Processes with Application of Boring Machine
Authors: Alshahrani Fatimah , Almanjahie Ibrahim M. , Khan Majid , Anwar Syed M. , Rasheed Zahid , Cheema Ammara N.
Published: February 2023

The quality characteristic(s) are assumed to follow the normal distribution in many control chart constructions, although this assumption may not hold in some instances. This study proposes the Bayesian-I and Bayesian-II Shewhart-type control charts for monitoring the Maxwell scale parameter in the phase II study. The posterior and predictive distributions are used to construct the control limits for the proposed Bayesian-I and Bayesian-II Shewhart-type control charts, respectively. Various performance indicators, including average run length, quadratic loss, relative average run length, and performance comparison index, are utilized to evaluate the performance of the proposed control charts. The Bayesian-I and Bayesian-II Shewhart-type control charts are compared to their competitive CUSUMV, EWMAV and V control charts. Sensitivity analysis is also performed to study the effect of hyperparameter values on the performance behavior of the proposed control charts. Finally, real-life data is analyzed for the implementation of the proposed control charts.
Evaluation of Forward Osmosis and Low-Pressure Reverse Osmosis with a Tubular Membrane for the Concentration of Municipal Wastewater and the Production of Biogas
Authors: Salamanca Mónica , Palacio Laura , Hernandez Antonio , Peña Mar , Prádanos Pedro
Published: February 2023

Currently, freshwater scarcity is one of the main issues that the world population has to face. To address this issue, new wastewater treatment technologies have been developed such as membrane processes. Among them, due to the energy disadvantages of pressure-driven membrane processes, Forward Osmosis (FO) and Low-Pressure Reverse Osmosis (LPRO) have been introduced as promising alternatives. In this study, the behavior of a 2.3 m2 tubular membrane TFO-D90 when working with municipal wastewater has been studied. Its performances have been evaluated and compared in two operating modes such as FO and LPRO. Parameters such as fouling, flow rates, water flux, draw solution concentration, organic matter concentration, as well as its recovery have been studied. In addition, the biogas production capacity has been evaluated with the concentrated municipal wastewater obtained from each process. The results of this study indicate that the membrane can work in both processes (FO and LPRO) but, from the energy and productivity point of view, FO is considered more appropriate mainly due to its lower fouling level. This research may offer a new point of view on low-energy and energy recovery wastewater treatment and the applicability of FO and LPRO for wastewater concentration.
A Guide to Your Desired Lipid-Asymmetric Vesicles
Authors: Krompers Mona , Heerklotz Heiko
Published: February 2023

Liposomes are prevalent model systems for studies on biological membranes. Recently, increasing attention has been paid to models also representing the lipid asymmetry of biological membranes. Here, we review in-vitro methods that have been established to prepare free-floating vesicles containing different compositions of the classic two-chain glycero- or sphingolipids in their outer and inner leaflet. In total, 72 reports are listed and assigned to four general strategies that are (A) enzymatic conversion of outer leaflet lipids, (B) re-sorting of lipids between leaflets, (C) assembly from different monolayers and (D) exchange of outer leaflet lipids. To guide the reader through this broad field of available techniques, we attempt to draw a road map that leads to the lipid-asymmetric vesicles that suit a given purpose. Of each method, we discuss advantages and limitations. In addition, various verification strategies of asymmetry as well as the role of cholesterol are briefly discussed. The ability to specifically induce lipid asymmetry in model membranes offers insights into the biological functions of asymmetry and may also benefit the technical applications of liposomes.
Effect of Cytochrome C on the Conductance of Asolectin Membranes and the Occurrence of Through Pores at Different pHs
Authors: Anosov Andrey , Borisova Elizaveta , Smirnova Elena , Korepanova Eugenia , Osipov Anatoly
Published: February 2023

The study of the electrical parameters of asolectin bilayer lipid membranes in the presence of cytochrome c (cyt c) at various concentrations showed that an increase in the concentration of cyt c leads to an increase in the membrane conductance and the appearance of through pores. The studied membranes did not contain cardiolipin, which is commonly used in studying the effect of cyt c on membrane permeability. In the presence of cyt c, discrete current fluctuations were recorded. The occurrence of these fluctuations may be associated with the formation of through pores. The diameter of these pores was ~0.8 nm, which is smaller than the size of the cyt c globule (~3 nm). Measurements carried out at pH values from 6.4 to 8.4 showed that the concentration dependence of the membrane conductance increases with increasing pH. To assess the binding of cyt c to the bilayer, we measured the concentration and pH dependences of the difference in surface potentials induced by the unilateral addition of cyt c. The amount of bound cyt c at the same concentrations decreased with increasing pH, which did not correspond to the conductance trend. An analysis of conductance traces leads to the conclusion that an increase in the integral conductance of membranes is associated with an increase in the lifetime of pores. The formation of “long-lived” pores, of which the residence time in the open state is longer than in the closed state, was achieved at various combinations of pHs and cyt c concentrations: the higher the pH, the lower the concentration at which the long-lived pores appeared and, accordingly, a higher conductance was observed. The increase in conductance and the formation of transmembrane pores are not due to the electrostatic interaction between cyt c and the membrane. We hypothesize that an increase in pH leads to a weakening of hydrogen bonds between lipid heads, which allows cyt c molecules to penetrate into the membrane. This disrupts the order of the bilayer and leads to the occurrence of through pores.
Reduction Kinetics of Compact Hematite with Hydrogen from 600 to 1050 °C
Authors: He Junguo , Li Kejiang , Zhang Jianliang , Conejo Alberto N.
Published: February 2023

Reduction of iron ores with hydrogen is a solution to replace fossil fuels. For this reason, it is important to discuss previous discrepancies. Some previous studies suggest a rate minimum with respect to temperature. Our research work indicates that a rate minimum can be avoided. Thermogravimetric isothermal reduction experiments were carried out from 600 to 1050 °C with pure reagent ferric oxide and hydrogen using a tubular furnace. The morphology and chemical composition of the initial sample, consisting of particulate hematite (Fe2O3), and the final product, consisting of metallic iron (Fe°), was defined using scanning electron microscopy (SEM) and X-ray diffraction (XRD). The reduction rate for the conversion from hematite to magnetite (Fe2O3 to Fe3O4) was the highest, around 5 %/min, decreasing to around 2–5%/min for the second stage of conversion from magnetite to wüstite (Fe3O4 to FeO). This reduction rate remains almost constant from about 20–80% reduction, decreasing to 0.3–1%/min for the completion of reduction from wüstite to metallic iron (FeO to Fe°). The reduction controlling mechanism was evaluated based on the calculated apparent activation energy and fitting the experimental data to one gas-solid reaction equation. Under the experimental conditions in this work, the reduction rate of pure hematite with hydrogen linearly increased with temperatures from 600 to 1000 °C, without a rate minimum in this temperature range. Above 1000 °C, the reduction rate decreased due to sintering phenomena. This result suggests a maximum reduction temperature of 1000 °C using pure hematite and hydrogen as the reducing gas. The reduction controlling mechanisms identified using hydrogen as a reducing gas were chemical reaction for the conversion from hematite to wüstite and diffusion control for the final reduction from wüstite to metallic iron. Since the reduction rate from wüstite to metallic iron is the one that affects the overall rate of reduction, overall changes in porosity were also evaluated. Finally, the reduction of wüstite is schematically described.
Dynamic of Mining Systems: Impact of Cl− Ion Concentration on Heap Copper Leaching Process at Industrial Scale
Authors: Saldaña Manuel , Gálvez Edelmira , Gallegos Sandra , Madrid Felipe M. Galleguillos , Robles Pedro , Toro Norman
Published: February 2023

Analytical models are of vital importance to study the dynamics of complex systems, including the heap leaching process. In this work, a methodology to study the dynamics of copper recovery in the heap leaching by means of fit of analytical models that capture the leaching dynamics product of variations of leaching agents as a function of the feeding is proposed, establishing a first mode of operation keeping the leaching agent fixed (H2SO4) and a second operation mode, where Cl− is added to accelerate the reaction kinetics of sulfide minerals (secondary sulfides). Mineral recovery was modeled for the different modes of operation, dependent on the independent variables/control parameters time, heap height, leach flow rate, and feed granulometry. The results indicate that the recovery of ore from sulfide minerals is proportional to the addition of Cl−, reaching recovery levels of approximately 60%, very close to 65% recovery in conventional oxide leaching, using only H2SO4 as leaching agent. Additionally, high copper recoveries from sulfide ores are achieved at medium Cl− concentrations, but the increase in recovery at high Cl− concentrations is marginal.
Strength Analysis of Eight-Wheel Bogie of Bucket Wheel Excavator
Authors: Vulovic Snezana , Zivkovic Miroslav , Pavlovic Ana , Vujanac Rodoljub , Topalovic Marko
Published: February 2023

Crawler travel gear is a type of heavy vehicle propulsion that is commonly found in tanks, excavators, and specialized off-road vehicles. They have an advantage over wheels when it comes to robust vehicle weight distribution over soft terrain, and some disadvantages as well. They can damage paved roads and have complex design so, considering the enormous weight they must carry, their reliability must be determined and verified. The main parts of the assembly are the drive wheels, which move the crawler, and the supporting structure that holds four-wheel bogies and two-wheel bogies. In this paper, we present a methodology for FEM analysis of parts of an eight-wheel bogie according to DIN 22261-2 standard.
Research on Strip Profile Control Characteristics of 1500 mm Quintic CVC Mill
Authors: Wei Bangshuo , Li Hongbo , Wang Yuchao , Zhang Jie , Kong Ning , Liu Zhang , Liu Bo
Published: February 2023

Compared with cubic Continuously Variable Crown (CVC), quintic CVC presents integrated control capability of quadratic and quartic crown. In order to take full advantage of quintic CVC and have better comprehensive control of the edge wave, center wave, high order wave and complex wave in practical application, it is necessary to further clarify the complicated profile control characteristics of quintic CVC. In this paper, quintic CVC technology in a 1500 mm continuous hot rolling mill production line has been taken as the research object and use finite element method to study its profile control characteristics. Through finite element simulation, an integrated model of rolls and strip was established to analyze the influence of the shifting, bending force and rolling force on strip profile with different strip widths. Both crown adjustment area and transverse stiffness are gained to study the control capability of quintic CVC. The simulation results show that the positive shifting and positive bending of CVC work roll reduce the quadratic crown and increase the quartic crown, and the controlling effect of shifting on both quadratic and quartic crown is more remarkable than that of bending. The control capability of the crown increases with the increase of strip width. That is, wider strip has a larger crown adjustment area. Meanwhile, there is a strong coupling relationship that the increase of quadratic crown can lead to the decrease of the quartic crown, which is not good for the flexible control of strip profile. With the increase of rolling force, the quadratic crown of strip increases significantly, while the quartic crown does not change obviously. Additionally, the increase of strip width significantly increases the transverse stiffness of mill.
Precipitation Behavior of the Metastable Quasicrystalline I-Phase and θ′-Phase in Al-Cu-Mn Alloy
Authors: Mikhaylovskaya Anastasia V. , Mukhamejanova Aiymgul , Kotov Anton D. , Tabachkova Nataliya Yu. , Prosviryakov Alexey S. , Mochugovskiy Andrey G.
Published: February 2023

The precipitation behavior and mechanical properties for conventionally solidified Al-2.0wt.%Cu-2.0wt.%Mn alloy were studied. The supersaturated aluminum-based solid solution, CuAl2, Al6Mn and Al20Cu2Mn3 phases of solidification origin were identified after casting. The high temperature ageing of as-cast samples (T5 treatment) in a temperature range of 300–350 °C led to the formation of the metastable θ′ phase and equiaxed precipitates of the quasicrystalline-structured I-phase. The θ′ phase demonstrated a high size stability in a studied temperature range with a mean length of ~300 nm and a mean thickness of ~24 nm. A mean size of the I-phase precipitates varied in a range of ~30–50 nm depending on the treatment regimes. The rod-shaped T-phase precipitates were formed with an increase in ageing temperature to 400 °C. Mechanical properties were analyzed at room temperature in a solid solution-treated state. The increased yield strength at room temperature and 200–300 °C were observed after ageing at 300 °C for 148 h.
Numerical Investigation on the Service Life of a Liquid Rocket Engine Thrust Chamber
Authors: Ferraiuolo Michele , Giannella Venanzio , Armentani Enrico , Citarella Roberto
Published: February 2023

Rocket engine thrust chambers withstand very high temperatures and thermal gradients during service that induce multiple damaging phenomena such as plasticity, low-cycle-fatigue (LCF) and creep. Numerical models can be used during the design of these mechanical components in order to simulate the main mechanical damaging processes, accounting for complex material behavior as due to non-linear hardening phenomena and viscoplasticity. This work represents an improvement upon previous research by the authors, with particular reference to the addition of the Wang–Brown fatigue criterion, to consider the effects of multiaxiality and non-proportionality of loads, and the Voce model to account for non-linear isotropic hardening. A precipitation hardened copper alloy has been considered as the material of the thrust chamber internal structure. The most critical areas resulted to be on the internal surface of the chamber and in particular in correspondence of the throat region, consistently with experimental tests available in the literature conducted on similar geometries. Results demonstrated that low cycle fatigue and thermal ratcheting (plastic instability) are the dominant damaging phenomena for the considered test case.
Incorporation of Plant-Based Diet Surpasses Current Standards in Therapeutic Outcomes in Inflammatory Bowel Disease
Authors: Chiba Mitsuro , Morita Norikazu
Published: February 2023

There has been no study of the therapeutic effect of a plant-based diet (PBD) in inflammatory bowel disease (IBD) except for our studies in Japan. In this review, we describe the rationale for the requirement of PBD in IBD and the outcomes of our modality incorporating PBD together with a literature review. The biggest problem in current therapy for IBD is the lack of a widely appreciated ubiquitous environmental factor in IBD. Therefore, a radical strategy against IBD has not been established. Japanese data showed an increased incidence of IBD in association with dietary westernization. Current global consumption consists of an excess of unhealthy foods and a shortage of healthy foods recognized as pro-inflammatory. Patients with IBD are no exception. One of the recommended healthy reference diets is PBD recognized as anti-inflammatory. We assert that IBD occurs in susceptible individuals mainly as a result of our omnivorous (westernized) diet. Therefore, we developed and began to provide a PBD, a lacto-ovo-vegetarian diet, for IBD patients in 2003. Infliximab and PBD as first-line (IPF) therapy was administered for all patients with newly developed Crohn’s disease (CD) and for severe ulcerative colitis (UC). Our modality broke the barrier of primary nonresponders to biologics, with a remission rate of 96% in CD, and created a new relapse-free course in slightly over half of the patients (52%) with CD. Based on the rationale derived from available evidence and the clinical outcomes, PBD is highly recommended for IBD.
Serum Metabolites Associated with Muscle Hypertrophy after 8 Weeks of High- and Low-Load Resistance Training
Authors: Valério Denis F. , Castro Alex , Gáspari Arthur , Barroso Renato
Published: February 2023

The mechanisms responsible for the similar muscle growth attained with high- and low-load resistance training (RT) have not yet been fully elucidated. One mechanism is related to the mechanical stimulus and the level of motor unit recruitment; another mechanism is related to the metabolic response. We investigated the electromyographic signal amplitude (sEMG) and the general metabolic response to high-load RT (HL) and low-load resistance training (LL). We measured muscle thickness by ultrasound, sEMG amplitude by electromyography, and analysis of metabolites expressed through metabolomics. No differences were observed between the HL and LL groups for metabolic response and muscle thickness. A greater amplitude of sEMG was observed in the HL group. In addition, a correlation was observed between changes in muscle thickness of the vastus lateralis muscle in the HL group and levels of the metabolites carnitine, creatine, 3-hydroxyisovalerate, phenylalanine, asparagine, creatine phosphate, and methionine. In the LL group, a correlation was observed between changes in muscle thickness of the vastus lateralis muscle and levels of the metabolites acetoacetate, creatine phosphate, and oxypurinol. These correlations seem to be related to the characteristics of activated muscle fibers, the metabolic demand of the training protocols used, and the process of protein synthesis.
Replication Study of Molded Micro-Textured Samples Made of Ultra-High Molecular Weight Polyethylene for Medical Applications
Authors: Modica Francesco , Basile Vito , Surace Rossella , Fassi Irene
Published: February 2023

In articular joint implants, polymeric inserts are usually exploited for on-contact sliding surfaces to guarantee low friction and wear, a high load-bearing capacity, impact strength and stiffness, and biocompatibility. Surface micro-structuring can drastically reduce friction and wear by promoting hydrostatic friction due to synovial fluid. Ultra-High Molecular Weight Polyethylene (UHMWPE) is a suitable material for these applications due to its strong chemical resistance, excellent resistance to stress, cracking, abrasion, and wear, and self-lubricating property. However, surface micro-texturing of UHMWPE is hardly achievable with the currently available processes. The present study investigates UHMWPE’s micro-textured surface replication capability via injection molding, comparing the results with the more easily processable High-Density Polyethylene (HDPE). Four different micro-texture cavities were designed and fabricated on a steel mold by micro-EDM milling, and used for the experimental campaign. Complete samples were fabricated with both materials. Then, the mold and samples were geometrically characterized, considering the dimensions of the features and the texture layout. The replication analysis showed that HDPE samples present geometrical errors that span from 1% to 9% resulting in an average error of 4.3%. In comparison, the UHMWPE samples display a higher variability, although still acceptable, with percentage errors ranging from 2% to 31% and an average error of 11.4%.
Geochemistry of Waziristan Ophiolite Complex, Pakistan: Implications for Petrogenesis and Tectonic Setting
Authors: Jalil Raham , Alard Olivier , Schaefer Bruce , Ali Liaqat , Sajid Muhammad , Khedr Mohamed Zaki , Shah Mohammad Tahir , Anjum Muhammad Naveed
Published: February 2023

The Waziristan ophiolite complex (WOC), a segment of paleo-suture zone between the Indo-Pakistan plate to the south-east and the Afghan microplate to the north-west, is primarily composed of serpentinized dunites and serpentinites after harzburgites, crosscut by pyroxenites. The crustal portion dominantly comprises basalts and dolerites, with less abundant plagiogranites. Whole-rock XRF and trace element ICP-MS analyses were undertaken to determine the degree of melt extraction and subsequent geochemical depletion or enrichment of peridotite protoliths. The investigated peridotites are extremely refractory and show high Mg# values (0.88–0.92), low Al2O3 (0.19–0.96 wt%), total alkali values (0.02 < Na2O + K2O ≤ 0.20 wt%), CaO (0.04–0.73 wt%), and TiO2 (0.001–0.017 wt%), but are rich in Cr (up to 3550 ppm) and Ni (up to 2340 ppm). Bulk REE modelling suggests that Waziristan peridotites underwent a high degree (15%–25% melting) of melt extraction in the closed system of spinel-bearing peridotite facies at shallow depths above a subduction zone and, in their chemistry (Sc, REE, Al2O3, and MgO), resemble Izu-Bonin-Mariana (IBM) forearc peridotites. Their U-shaped REE patterns and trace elements resemble peridotites derived from supra-subduction zone (SSZ) settings, especially a forearc setting, and also reflect metasomatism by slab-derived fluids. The ultramafic rocks preserve depletion in REE content (0.03 < ΣREECN < 0.60), indicating the highly depleted nature of refractory peridotites. The basalts (Mg#, 0.48-0.68) are similar in composition to typical boninite and show low to moderate MgO (6.2–13.0 wt%), low total alkali content (0.01–4.45 wt%) and TiO2 (0.13–0.17 wt%), but are higher in Al2O3 (≈11.9 wt%). They show a sub-alkaline affinity and possess geochemical signatures that are transitional from island arc basalt (IAB) magmas to boninitic magmas due to the changes from an extensional to a compressional regime during the initiation of subduction. These geochemical signatures suggest the formation of basalts from melts, resulting from the re-melting of the depleted mantle during intra-oceanic subduction initiation. The higher Th/Nb and V/Ti ratios of the studied basalts further confirm their generation in an SSZ setting characterized by subduction-derived fluids under higher oxidizing conditions. The mafic-ultramafic rocks of the WOC were, therefore, likely formed during intra-oceanic subduction initiation (forearc spreading) in the SSZ setting; they were exhumed along a thrust fault, and obducted onto the forearc region as result of the collision between the Indian plate and the Afghan microplate.
Sedimentary Filling Evolution under Paleoclimate Transition—A Case Study from the Middle Jurassic Zhiluo Formation, Ordos Basin
Authors: Cui Liwei , Peng Nan , Liu Yongqing , Qiao Dawei , Liu Yanxue
Published: February 2023

Under a specific tectonic background, the change in paleoclimate can show different facies associations and depositional architecture. The Jurassic China continent was an important region for transforming the Paleotethys tectonic domain to the circum-Pacific tectonic domain, and its paleoclimate information was entirely preserved in the continental sedimentary successions. The Middle Jurassic Zhiluo Formation, in the Ordos Basin, was at just the critical period of paleostructure and paleoclimate transition, preserving considerable sedimentological evidence; however, little sedimentological research has been conducted under the transition. This study reconstructed the sedimentary filling characteristics of the Zhiluo Formation under paleoclimate transition based on field outcrop survey, thin section observation, geochemical indices, stratigraphic correlation, and depositional environment analysis. The results showed that with the paleoclimate change from warm and humid to hot and arid, the sedimentary facies of the Zhiluo Formation were characterised by the change from the braided river/braided river delta in the J2z1-1 sedimentary period to the meandering river/meandering river delta in the J2z1-2 sedimentary period, and finally the change to the meandering river, meandering river delta, and lacustrine in the J2z2 sedimentary period. The combined action of the southern super monsoon effect, the increasing global CO2 concentrations, the moving southward of the East Asian block, and the terrain elevation difference, changed the basin’s climate from warm and humid to hot and semi-arid/arid. This study provides a crucial basis for reconstructing the interplay between paleoclimate and paleotectonics, and guiding sedimentology and paleoenvironment research on East Asia during the Middle Jurassic period.
Recovery of Mg from H2SO4 Leaching Solution of Serpentine to Precipitation of High-Purity Mg(OH)2 and 4MgCO3·Mg(OH)2·4H2O
Authors: Chen Yingli , Yang Xiyun , Wu Linglong , Tong Lirong , Zhu Jing
Published: February 2023

This paper describes a leaching-purifying-precipitation process to recover magnesium from serpentine acid-leaching solution and to synthesize high purity Mg(OH)2 and 4MgCO3·Mg(OH)2·4H2O. Fe, Al, and Cr in the leaching solution were removed using the oxidation precipitation method with active MgO as a precipitant and H2O2 as an oxidant. Ni, Co and Mn were removed by Na2S precipitation to obtain a pure MgSO4 solution. Mg2+ ions were first precipitated with NH3·H2O to synthesize Mg(OH)2, followed by NH4HCO3 precipitation to obtain 4MgCO3·Mg(OH)2·4H2O. A small part of MgSO4 coprecipitates with Mg(OH)2 to form MgSO4·5Mg(OH)2·3H2O. The Mg(OH)2 was aged with a diluted NaOH solution to remove the sulfur; the two-stage precipitation percentage of Mg is 96.3%. Mg(OH)2 has a purity of 98.48% with a sulfur content of 0.28%. This process provides a promising method for the high-efficiency recovery of Mg and the large-scale production of the high purity of Mg(OH)2 from the serpentine.
Mineralogical and Geochemical Constraints on the Occurrence Forms of REEs in Carboniferous Karst Bauxite, Central Guizhou Province, Southwest China: A Case Study of Lindai Bauxite
Authors: Luo Chaokun , Liang Peng , Yang Ruidong , Gao Junbo , Chen Qun , Mo Hongcheng
Published: February 2023

Karst bauxite is a major source of aluminum and contains high concentrations of trace elements such as Li, Ga, Sc, and rare earth elements (REEs). It is regarded as a potential non-conventional REE source due to the increasing demand for REEs. This study provides new mineralogical and geochemical evidence of a Lindai bauxite deposit in central Guizhou Province, aiming to analyze the genesis of REE minerals and reveal the forms of REEs occurring in these deposits. The results indicate that a large number of detrital and authigenic rare-earth phosphate minerals, including monazite and xenotime, were identified. In terms of their genesis, the authigenic monazite was mainly precipitated under alkaline and reducing conditions, whereas the authigenic xenotime was formed in acidic and reducing conditions. The mineralogical evidence detected by scanning electron microscopy with energy dispersive spectrometry (SEM-EDS) and a TESCAN Integrated Mineral Analyzer (TIMA) suggests that the REEs in the Lindai bauxite exhibit multiple forms, including rare-earth phosphate minerals (monazite and xenotime) and REE scavenging by hematite and anatase phases. Among them, the anatase controls some LREE (such as La, Ce, and Pr) distributions in addition to monazite, whereas the hematite also controls relatively large amounts of Sm, Eu, and HREE (such as Gd, Tb, Dy, Ho, Er, Tm, and Lu) distributions. According to the calculation of the percentage of REE-bearing mineral phases obtained by a TIMA analysis, REE scavenging by hematite accounted for 93.28% of all forms of REEs, REE scavenging by anatase accounted for 5.88%, monazite accounted for 0.67%, and xenotime accounted for 0.17%. This study provides new evidence of the forms of REEs occurring in Carboniferous karst bauxite in central Guizhou Province.
The Pleiotropic Role of Extracellular ATP in Myocardial Remodelling
Authors: Sudi Suhaini , Thomas Fiona Macniesia , Daud Siti Kadzirah , Ag Daud Dayang Maryama , Sunggip Caroline
Published: February 2023

Myocardial remodelling is a molecular, cellular, and interstitial adaptation of the heart in response to altered environmental demands. The heart undergoes reversible physiological remodelling in response to changes in mechanical loading or irreversible pathological remodelling induced by neurohumoral factors and chronic stress, leading to heart failure. Adenosine triphosphate (ATP) is one of the potent mediators in cardiovascular signalling that act on the ligand-gated (P2X) and G-protein-coupled (P2Y) purinoceptors via the autocrine or paracrine manners. These activations mediate numerous intracellular communications by modulating the production of other messengers, including calcium, growth factors, cytokines, and nitric oxide. ATP is known to play a pleiotropic role in cardiovascular pathophysiology, making it a reliable biomarker for cardiac protection. This review outlines the sources of ATP released under physiological and pathological stress and its cell-specific mechanism of action. We further highlight a series of cardiovascular cell-to-cell communications of extracellular ATP signalling cascades in cardiac remodelling, which can be seen in hypertension, ischemia/reperfusion injury, fibrosis, hypertrophy, and atrophy. Finally, we summarize current pharmacological intervention using the ATP network as a target for cardiac protection. A better understanding of ATP communication in myocardial remodelling could be worthwhile for future drug development and repurposing and the management of cardiovascular diseases.
Towards DNA-Based Methods Analysis for Honey: An Update
Authors: Soares Sónia , Rodrigues Francisca , Delerue-Matos Cristina
Published: February 2023

Honey is a natural product widely consumed all over the world due to its relationship with healthy benefits. Additionally, environmental and ethical issues have a higher weight in the consumer’s choice to buy honey as a natural product. Following the high demand of this product, several approaches have been suggested and developed aiming at the assessment of honey’s quality and authenticity. Target approaches, such as pollen analysis, phenolic compounds, sugars, volatile compounds, organic acids, proteins, amino acids, minerals, and trace elements, showed an efficacy, particularly concerning the honey origin. However, a special highlight is given to DNA markers, due to their useful applicability in environmental and biodiversity studies, besides the geographical, botanical, and entomological origins. Different DNA target genes were already explored for addressing diverse sources of honey DNA, with DNA metabarcoding attaining a relevant importance. This review aims to describe the latest advances on DNA-based methods applied in honey related studies, identifying the research needs for the development of new and additional required methodologies, and to select the most adequate tools for future research projects.
Electronic Modulation and Structural Engineering of Carbon-Based Anodes for Low-Temperature Lithium-Ion Batteries: A Review
Authors: Sun Jiaxun , Ye Lingqian , Zhao Xinran , Zhang Peipei , Yang Jun
Published: February 2023

Lithium-ion batteries (LIBs) have become the preferred battery system for portable electronic devices and transportation equipment due to their high specific energy, good cycling performance, low self-discharge, and absence of memory effect. However, excessively low ambient temperatures will seriously affect the performance of LIBs, which are almost incapable of discharging at −40~−60 °C. There are many factors affecting the low-temperature performance of LIBs, and one of the most important is the electrode material. Therefore, there is an urgent need to develop electrode materials or modify existing materials in order to obtain excellent low-temperature LIB performance. A carbon-based anode is one candidate for use in LIBs. In recent years, it has been found that the diffusion coefficient of lithium ion in graphite anodes decreases more obviously at low temperatures, which is an important factor limiting its low-temperature performance. However, the structure of amorphous carbon materials is complex; they have good ionic diffusion properties, and their grain size, specific surface area, layer spacing, structural defects, surface functional groups, and doping elements may have a greater impact on their low-temperature performance. In this work, the low-temperature performance of LIBs was achieved by modifying the carbon-based material from the perspectives of electronic modulation and structural engineering.
Human Pluripotent Stem Cell–Mesenchymal Stem Cell-Derived Exosomes Promote Ovarian Granulosa Cell Proliferation and Attenuate Cell Apoptosis Induced by Cyclophosphamide in a POI-Like Mouse Model
Authors: Zhang Lifan , Ma Yabo , Xie Xianguo , Du Changzheng , Zhang Yan , Qin Shaogang , Xu Jinrui , Wang Chao , Yang Yi , Xia Guoliang
Published: February 2023

Premature ovarian insufficiency (POI) is a complex disease which causes amenorrhea, hypergonadotropism and infertility in patients no more than 40 years old. Recently, several studies have reported that exosomes have the potential to protect ovarian function using a POI-like mouse model induced by chemotherapy drugs. In this study, the therapeutic potential of exosomes derived from human pluripotent stem cell–mesenchymal stem cells (hiMSC exosomes) was evaluated through a cyclophosphamide (CTX)-induced POI-like mouse model. POI-like pathological changes in mice were determined by serum sex-hormones levels and the available number of ovarian follicles. The expression levels of cellular proliferation proteins and apoptosis-related proteins in mouse ovarian granulosa cells were measured using immunofluorescence, immunohistochemistry and Western blotting. Notably, a positive effect on the preservation of ovarian function was evidenced, since the loss of follicles in the POI-like mouse ovaries was slowed. Additionally, hiMSC exosomes not only restored the levels of serum sex hormones, but also significantly promoted the proliferation of granulosa cells and inhibited cell apoptosis. The current study suggests that the administration of hiMSC exosomes in the ovaries can preserve female-mouse fertility.
Experimental Determination of a Chiral Ternary Solubility Diagram and Its Interpretation in Gas Antisolvent Fractionation
Authors: Kőrösi Márton , Varga Csaba , Tóth Péter , Buczkó Noémi , Varga Erzsébet , Székely Edit
Published: February 2023

Although crystallization has been widely applied for the enantiomeric enrichment of non-racemates both in research and in industrial applications, the physical–chemical background of chiral crystallizations is not as frequently discussed. A guide for the experimental determination of such phase equilibrium information is lacking. In the current paper, the experimental investigation of chiral melting phase equilibria, chiral solubility phase diagrams and their application in atmospheric and supercritical carbon dioxide-assisted enantiomeric enrichment is described and compared. Benzylammonium mandelate is a racemic compound; it shows eutectic behavior when molten. A similar eutonic composition was observed in its methanol phase diagram at 1 °C. The influence of the ternary solubility plot could be unequivocally discovered in atmospheric recrystallization experiments, which proved that the crystalline solid phase and the liquid phase were in an equilibrium. The interpretation of the results obtained at 20 MPa and 40 °C, using the methanol–carbon dioxide mixture as a pseudo-component, was more challenging. Although the eutonic composition was found to be the limiting enantiomeric excess value in this purification process as well, the high-pressure gas antisolvent fractionation results were only clearly thermodynamically controlled in certain concentration ranges.
Quantum Computational, Spectroscopic (FT-IR, FT-Raman, NMR, and UV–Vis) Hirshfeld Surface and Molecular Docking-Dynamics Studies on 5-Hydroxymethyluracil (Monomer and Trimer)
Authors: Kumar Mohit , Jaiswar Gautam , Afzal Mohd. , Muddassir Mohd. , Alarifi Abdullah , Fatima Aysha , Siddiqui Nazia , Ayub Rashid , Abduh Naaser A. Y. , Saeed Waseem Sharaf , Javed Saleem
Published: February 2023

For many decades, uracil has been an antineoplastic agent used in combination with tegafur to treat various human cancers, including breast, prostate, and liver cancer. Therefore, it is necessary to explore the molecular features of uracil and its derivatives. Herein, the molecule’s 5-hydroxymethyluracil has been thoroughly characterized by NMR, UV–Vis, and FT-IR spectroscopy by means of experimental and theoretical analysis. Density functional theory (DFT) using the B3LYP method at 6-311++G(d,p) was computed to achieve the optimized geometric parameters of the molecule in the ground state. For further investigation and computation of the NLO, NBO, NHO analysis, and FMO, the improved geometrical parameters were utilized. The potential energy distribution was used to allocate the vibrational frequencies using the VEDA 4 program. The NBO study determined the relationship between the donor and acceptor. The molecule’s charge distribution and reactive regions were highlighted using the MEP and Fukui functions. Maps of the hole and electron density distribution in the excited state were generated using the TD-DFT method and PCM solvent model in order to reveal electronic characteristics. The energies and diagrams for the lowest unoccupied molecular orbital (LUMO) and the highest occupied molecular orbital (HOMO) were also provided. The HOMO–LUMO band gap estimated the charge transport within the molecule. When examining the intermolecular interactions in 5-HMU, Hirshfeld surface analysis was used, and fingerprint plots were also produced. The molecular docking investigation involved docking 5-HMU with six different protein receptors. Molecular dynamic simulation has given a better idea of the binding of the ligand with protein.
The Effect of the Pre-Strain Process on the Strain Engineering of Two-Dimensional Materials and Their van der Waals Heterostructures
Authors: Han Jinkun , Yue Xiaofei , Shan Yabing , Chen Jiajun , Ekoya Borgea G. M. , Hu Laigui , Liu Ran , Qiu Zhijun , Cong Chunxiao
Published: February 2023

Two-dimensional (2D) materials and their van der Waals stacked heterostructures (vdWH) are becoming the rising and glowing candidates in the emerging flexible nanoelectronics and optoelectronic industry. Strain engineering proves to be an efficient way to modulate the band structure of 2D materials and their vdWH, which will broaden understanding and practical applications of the material. Therefore, how to apply desired strain to 2D materials and their vdWH is of great importance to get the intrinsic understanding of 2D materials and their vdWH with strain modulation. Here, systematic and comparative studies of strain engineering on monolayer WSe2 and graphene/WSe2 heterostructure are studied by photoluminescence (PL) measurements under uniaxial tensile strain. It is found that contacts between graphene and WSe2 interface are improved, and the residual strain is relieved through the pre-strain process, which thus results in the comparable shift rate of the neutral exciton (A) and trion (AT) of monolayer WSe2 and graphene/WSe2 heterostructure under the subsequent strain release process. Furthermore, the PL quenching occurred when the strain is restored to the original position also indicates the pre-strain process to 2D materials, and their vdWH is important and necessary for improving the interface contacts and reducing the residual strain. Thus, the intrinsic response of the 2D material and their vdWH under strain can be obtained after the pre-strain treatment. These findings provide a quick, fast and efficient way to apply desired strain and also have important significance in guiding the use of 2D materials and their vdWH in the field of flexible and wearable devices.