bluuebunny/crossref_metadata_2025 huggingface dataset:
Preparation of Nanostructured Sn/Ti Oxide Hybrid Films with Terpineol/PEG-Based Nanofluids: Perovskite Solar Cell Applications
Authors: Vafaei Saeid , Boddu Vamsi Krishna , Jala Stephen , Bezawada Pavan Kumar , Hattori Nagisa , Higashi Seiho , Sugiura Takashi , Manseki Kazuhiro
Published: April 2023

Tin oxide (SnO2) and titanium dioxide (TiO2) are recognized as attractive energy materials applicable for lead halide perovskite solar cells (PSCs). Sintering is one of the effective strategies for improving the carrier transport of semiconductor nanomaterials. Using the alternative metal-oxide-based ETL, nanoparticles are often used in a way that they are dispersed in a precursor liquid prior to their thin-film deposition. Currently, the creation of PSCs using nanostructured Sn/Ti oxide thin-film ETL is one of the topical issues for the development of high-efficiency PSCs. Here, we demonstrate the preparation of terpineol/PEG-based fluid containing both tin and titanium compounds that can be utilized for the formation of a hybrid Sn/Ti oxide ETL on a conductive substrate (F-doped SnO2 glass substrate: FTO). We also pay attention to the structural analysis of the Sn/Ti metal oxide formation at the nanoscale using a high-resolution transmission electron microscope (HR-TEM). The variation of the nanofluid composition, i.e., the concentration of tin and titanium sources, was examined to obtain a uniform transparent thin film by spin-coating and sintering processes. The maximum power conversion efficiency was obtained for the concentration condition of [SnCl2·2H2O]/[titanium tetraisopropoxide (TTIP)] = 25:75 in the terpineol/PEG-based precursor solution. Our method for preparing the ETL nanomaterials provides useful guidance for the creation of high-performance PSCs using the sintering method.
Creep Behavior Characterization of Nickel-Based Single-Crystal Superalloy DD6 Thin-Walled Specimens Based on a 3D-DIC Method
Authors: Zhang Yue , Hu Jiangkun , Kang Lixia , He Yuhuai , Xu Wei
Published: April 2023

The thickness debit effect of creep behavior has been a focal point of nickel-based single-crystal superalloy research, and there is a need for an advanced creep deformation measurement method. This study developed a novel high-temperature creep test system based on a single-camera stereo digital image correlation (DIC) method with four plane mirrors to conduct creep tests on thin-walled specimens of a nickel-based single-crystal alloy, DD6, with thicknesses of 0.6 mm and 1.2 mm under experimental conditions of 980 °C/250 MPa. The reliability of the single-camera stereo DIC method in measuring long-term deformation at a high temperature was experimentally verified. The experimental results show that the creep life of the thinner specimen was significantly shorter. It was found the lack of coordination in the creep deformation process of the edge and middle section of the thin-walled specimens may be an important factor in the thickness debit effect according to the full-field strain contour. By comparing the local strain curve at the rupture point with the average creep strain curve, it was found that the creep rate at the rupture point was less affected by the specimen thickness during the secondary creep stage, while the average creep rate in the working section significantly increased as the wall thickness decreased. The thicker specimen usually had a higher average rupture strain and higher damage tolerance, which prolonged the rupture time.
Illumination of Interior Spaces through Structures Made of Unified Slabs of High-Performance Light-Transmitting Concrete with Embedded Optical Fibers
Authors: Štochl Nikola , Vychytil Jaroslav , Hájek Petr
Published: April 2023

Light-transmitting concrete as a building material already exists in many forms, but its light properties and the possibilities of using it to improve the lighting of interior spaces have not been investigated in detail yet. This paper focuses on the illumination of interior spaces using constructions made of light-transmitting concrete, which will allow light to pass between individual spaces. The experimental measurements carried out are divided into two typical situations using reduced room models. The first part of the paper focuses on the illumination of the room through the penetration of daylight through the ceiling made of light-transmitting concrete. The second part of the paper investigates the transmission of artificial light from one room to another through a non-load-bearing dividing structure composed of unified slabs of light-transmitting concrete. For the experiments, several models and samples were created for comparison. The first step of the experiment was to create slabs of light-transmitting concrete. While there are many options to produce such a slab, the best option is to use high-performance concrete with glass-fiber reinforcement, which improves the load transfer properties, and plastic optical fibers for light transmission. By adding optical fibers, we can achieve the transmission of light between any two spaces. For both of the experiments, we used reduced-scale models of rooms. Slabs with dimensions of 250 × 250 × 20 mm and 250 × 250 × 30 mm were used in three versions: concrete slabs with optical fibers, concrete slabs with air holes and solid slabs. The experiment measured and compared the level of illumination at several points in the model as it passed through each of the three different slabs. Based on the results of these experiments, it was concluded that the interior level of illumination of any space can be improved by using light-transmitting concrete, especially those without access to natural light. The experiment also assessed the strength properties of the slabs in relation to their intended use and compares them with the properties of stone slabs used as cladding.
Surface Cleaning and Passivation Technologies for the Fabrication of High-Efficiency Silicon Heterojunction Solar Cells
Authors: Shi Cuihua , Shi Jiajian , Guan Zisheng , Ge Jia
Published: April 2023

Silicon heterojunction (SHJ) solar cells are increasingly attracting attention due to their low-temperature processing, lean steps, significant temperature coefficient, and their high bifacial capability. The high efficiency and thin wafer nature of SHJ solar cells make them ideal for use as high-efficiency solar cells. However, the complicated nature of the passivation layer and prior cleaning render a well-passivated surface difficult to achieve. In this study, developments and the classification of surface defect removal and passivation technologies are explored. Further, surface cleaning and passivation technologies of high-efficiency SHJ solar cells within the last five years are reviewed and summarized.
Generation of Photonic Nanojet Using Gold Film Dielectric Microdisk Structure
Authors: Zeng Xintao , Su Ning , Zhang Weiming , Ye Zhibin , Wu Pinghui , Liu Bin
Published: April 2023

Due to their narrow beam waist size, high intensity, and long propagation distance, photonic nanojets (PNJs) can be used in various fields such as nanoparticle sensing, optical subwavelength detection, and optical data storage. In this paper, we report a strategy to realize an SPP-PNJ by exciting a surface plasmon polariton (SPP) on a gold-film dielectric microdisk. In detail, an SPP is excited by the grating–coupling method, then it irradiates the dielectric microdisk to form an SPP-PNJ. The characteristics of the SPP-PNJ, including maximum intensity, full width at half maximum (FWHM), and propagation distance, are studied by using finite difference time domain (FDTD) numerical solutions. The results demonstrate that the proposed structure can produce a high-quality SPP-PNJ, the maximum quality factor of which is 62.20, and the propagation distance of the SPP-PNJ is 3.08 λ. Furthermore, the properties of the SPP-PNJ can be modified flexibly by changing the thickness and refractive index of the dielectric microdisk.
Selective Laser Melting Additive Manufactured Tantalum: Effect of Microstructure and Impurities on the Strengthening-Toughing Mechanism
Authors: Lian Fengjun , Chen Longqing , Wu Changgui , Zhao Zhuang , Tang Jingang , Zhu Jun
Published: April 2023

The balance between the strength and the toughness of pure tantalum (Ta) fabricated with selective laser melting (SLM) additive manufacturing is a major challenge due to the defect generation and affinity for oxygen and nitrogen. This study investigated the effects of energy density and post-vacuum annealing on the relative density and microstructure of SLMed tantalum. The influences of microstructure and impurities on strength and toughness were mainly analyzed. The results indicated that the toughness of SLMed tantalum significantly increased due to a reduction in pore defects and oxygen-nitrogen impurities, with energy density decreasing from 342 J/mm3 to 190 J/mm3. The oxygen impurities mainly stemmed from the gas inclusions of tantalum powders, while nitrogen impurities were mainly from the chemical reaction between the molten liquid tantalum and nitrogen in the atmosphere. The proportion of <110> texture decreased after vacuum-annealing at 1200 °C, while that of the <100> texture increased. Concurrently, the density of dislocations and small-angle grain boundaries significantly decreased while the resistance of the deformation dislocation slip was significantly reduced, enhancing the fractured elongation up to 28% at the expense of 14% tensile strength.
Structure and Oxidation Behavior of Multicomponent (Hf,Zr,Ti,Nb,Mo)C Carbide Ceramics
Authors: Mirovaya Elena , Burlachenko Alexander , Kulagin Nikolay , Mirovoy Yuriy , Neiman Alexey , Buyakova Svetlana
Published: April 2023

Multicomponent ceramics based on transition metals carbides are widely known for their excellent physicomechanical properties and thermal stability. The variation of the elemental composition of multicomponent ceramics provides the required properties. The present study examined the structure and oxidation behavior of (Hf,Zr,Ti,Nb,Mo)C ceramics. Single-phase ceramic solid solution (Hf,Zr,Ti,Nb,Mo)C with FCC structure was obtained by sintering under pressure. It is shown that during the mechanical processing of an equimolar powder mixture of TiC–ZrC–NbC–HfC–Mo2C carbides, the formation of double and triple solid solutions occurs. The hardness of (Hf,Zr,Ti,Nb,Mo)C ceramic was found at 15 ± 0.8 GPa, compressive ultimate strength—at 1.6 ± 0.1 GPa and fracture toughness—at 4.4 ± 0.1 MPa∙m1/2. The oxidation behavior of the produced ceramics in an oxygen-containing atmosphere was studied in the range of 25 to 1200 °C by means of high-temperature in situ diffraction. It was demonstrated that (Hf,Zr,Ti,Nb,Mo)C ceramics oxidation is a two-stage process accompanied by the change of oxide layer phase composition. As a possible mechanism of oxidation, diffusion of oxygen into the ceramic bulk results in the formation of a complex oxide layer made of c–(Zr,Hf,Ti,Nb)O2, m–(Zr,Hf)O2, Nb2Zr6O17 and (Ti,Nb)O2 was proposed.
Diffusion-Induced Instability of the Periodic Solutions in a Reaction-Diffusion Predator-Prey Model with Dormancy of Predators
Authors: Wang Mi
Published: April 2023

A reaction-diffusion predator-prey model with the dormancy of predators is considered in this paper. We are concerned with the long-time behaviors of the solutions of this system. We divided our investigations into two cases: for the ODEs system, we study the existence and stability of the equilibrium solutions and derive precise conditions on system parameters so that the system can undergo Hopf bifurcations around the positive equilibrium solution. Moreover, the properties of Hopf bifurcation are studied in detail. For the reaction-diffusion system, we are able to derive conditions on the diffusion coefficients so that the spatially homogeneous Hopf bifurcating periodic solutions can undergo diffusion-triggered instability. To support our theoretical analysis, we also include several numerical results.
General Approach to the Evolving Plasma Equilibria with a Resistive Wall in Tokamaks
Authors: Pustovitov Vladimir D. , Chukashev Nikolay V.
Published: April 2023

The dynamic problem of plasma equilibrium in a tokamak is considered taking into account the electromagnetic reaction of the vacuum vessel resistive wall. The currents induced in the wall during transient events contribute to the external magnetic field that determines the plasma shape and position. Accordingly, the plasma geometry must evolve so that the inductive excitation of the wall current would properly compensate for the resistive losses. Simultaneous consideration of these factors presents the main difficulty of the description. It is performed in a general form using the Green’s function method that guarantees the mathematical accuracy of expressions for the magnetic fields from each source. At the same time, it is desirable to minimize the related complications, which is one of the goals here. The starting point is the standard solution of the external equilibrium problem given by integral relating the poloidal magnetic flux to the magnetic field at the plasma boundary. In the evolutionary problem, the additional equations for the plasma-wall electromagnetic coupling are transformed to an equation with a similar integral over the wall, but with either the time derivative of the poloidal magnetic flux or the wall current density in the integrand. The mentioned similarity allows to use the already developed techniques, which makes this formulation compact and convenient. It provides the basis for extension of the existing analytical theory of equilibrium to the case with non-circular plasma and wall.
Extraction, Structural Characterization, and In Vivo Anti-Inflammatory Effect of Alginate from Cystoseira crinita (Desf.) Borry Harvested in the Bulgarian Black Sea
Authors: Kokova Vesela , Lukova Paolina , Baldzhieva Alexandra , Katsarov Plamen , Delattre Cédric , Molinié Roland , Petit Emmanuel , Elboutachfaiti Redouan , Murdjeva Marianna , Apostolova Elisaveta
Published: April 2023

The aim of this study was to identify the chemical composition and sequential structure of alginate isolated from C. crinita harvested in the Bulgarian Black Sea, as well as its effects in histamine-induced paw inflammation in rats. The serum levels of TNF-α, IL-1β, IL-6, and IL-10 in rats with systemic inflammation, and the levels of TNF-α in a model of acute peritonitis in rats were also investigated. The structural characterization of the polysaccharide was obtained by FTIR, SEC-MALS, and 1H NMR. The extracted alginate had an M/G ratio of 1.018, a molecular weight of 7.31 × 104 g/mol, and a polydispersity index of 1.38. C. crinita alginate in doses of 25 and 100 mg/kg showed well-defined anti-inflammatory activity in the model of paw edema. A significant decrease in serum levels of IL-1β was observed only in animals treated with C. crinita alginate in a dose of 25 mg/kg bw. The concentrations of TNF-α and IL-6 in serum were significantly reduced in rats treated with both doses of the polysaccharide, but no statistical significance was observed in the levels of the anti-inflammatory cytokine IL-10. A single dose of alginate did not significantly alter the levels of the pro-inflammatory cytokine TNF-α in the peritoneal fluid of rats with a model of peritonitis.
Weight Regain in the Second Year after Sleeve Gastrectomy Could Be a Predictor of Long-Term Outcomes?
Authors: Kapała Jan , Maroszczuk Tomasz , Lewandowska Julia , Lech Paweł , Dowgiałło-Gornowicz Natalia
Published: April 2023

Background and Objectives: Sleeve gastrectomy (SG) is an effective surgical procedure in the treatment of obesity. However, a significant percentage of patients suffer from weight regain over long-term follow-up. The mechanisms responsible for this process are still poorly understood. The aim of the study is to evaluate the predictive effect of weight regain in the second year after SG on long-term bariatric surgery effectiveness. Methods: A retrospective cohort study was performed using the database of routinely collected information about patients undergoing SG in the Department of General, Minimally Invasive and Elderly Surgery in Olsztyn. Patients were divided into two groups according to the change in body weight between the first and second years after the surgery: weight gainers (WG) and weight maintainers (WM). Results: A study group consisting of 206 patients, with follow-up over 5 years, was included in the study. The WG group consisted of 69 patients while the WM group had 137 patients. There were no significant differences between the patient characteristics (p > 0.05). The WM group had a mean %EWL of 7.45% (SD, 15.83%) and %TWL of 3.74 (SD, 8.43). The WG group had a mean %EWL of 22.78% (SD, 17.11%) and %TWL of 11.29% (SD, 8.68). The difference between the groups was statistically significant (p < 0.05). The study showed significantly better results in WM compared to WG (p < 0.05). Conclusion: Weight regain in the second year after SG may be a good factor for long-term bariatric surgery effectiveness prognosis.
Potassium Ion Channels in Glioma: From Basic Knowledge into Therapeutic Applications
Authors: Younes Samar , Mourad Nisreen , Salla Mohamed , Rahal Mohamad , Hammoudi Halat Dalal
Published: April 2023

Ion channels, specifically those controlling the flux of potassium across cell membranes, have recently been shown to exhibit an important role in the pathophysiology of glioma, the most common primary central nervous system tumor with a poor prognosis. Potassium channels are grouped into four subfamilies differing by their domain structure, gating mechanisms, and functions. Pertinent literature indicates the vital functions of potassium channels in many aspects of glioma carcinogenesis, including proliferation, migration, and apoptosis. The dysfunction of potassium channels can result in pro-proliferative signals that are highly related to calcium signaling as well. Moreover, this dysfunction can feed into migration and metastasis, most likely by increasing the osmotic pressure of cells allowing the cells to initiate the “escape” and “invasion” of capillaries. Reducing the expression or channel blockage has shown efficacy in reducing the proliferation and infiltration of glioma cells as well as inducing apoptosis, priming several approaches to target potassium channels in gliomas pharmacologically. This review summarizes the current knowledge on potassium channels, their contribution to oncogenic transformations in glioma, and the existing perspectives on utilizing them as potential targets for therapy.
Effect of Tempering Temperature on Microstructure and Mechanical Properties of 35CrMo Steel
Authors: Ren Qichao , Kou Ziming , Wu Juan , Hou Tengyan , Xu Peng
Published: April 2023

In this paper, the influence mechanism of tempering temperature on the microstructure and mechanical properties of 35CrMo steel used in the hammerhead of piston-type impact pile hammer is systematically analyzed. The microstructure was characterized by scanning and transmission electron microscope, X-ray diffraction, and electron backscattering diffraction, and the mechanical properties were tested by the uniaxial tensile test and Charpy V-notch impact test. The results show that after tempering at 580–680 °C, the microstructure of 35CrMo is tempered sorbite. With the increase in tempering temperature, the α phase in the matrix gradually recovers, the dislocation density decreases, the low-angle grain boundaries gradually change to the high-angle grain boundaries, and the carbides gradually change from long rod-shaped network continuous distribution to spherical uniform dispersion distribution, but all of them are M3C. Meanwhile, with the increase in tempering temperature, the strength decreases and the toughness increases, which is mainly affected by dislocation density and matrix supersaturation. Furthermore, 35CrMo enters the two-phase zone after tempering at 710–740 °C, and its microstructure is lamellar martensite, with carbide dissolved. At this point, its mechanical properties mainly depend on grain size.
Investigation of Situational Correlations of Wire Electrical Discharge Machining of Superhard Materials with Acoustic Emission Characteristics
Authors: Grigoriev Sergey N. , Kozochkin Mikhail P. , Porvatov Artur N. , Malakhinsky Alexander P. , Melnik Yury A.
Published: April 2023

The purpose of this research is to find relationships between the parameters of the acoustic emission signals accompanying the electroerosive processing with a wire electrode of metals and hard alloys and the most important process indicators. These indicators include an increase in the concentration of erosion products in the interelectrode gap, an increase in the probability of wire electrode breakage, the efficiency of the supplied energy, the current productivity. This article presents the results of the study of acoustic emission signals during the processing of hard alloys with a cutting machine. The main focus is on the period preceding the breakage of the wire electrode. Changes in the parameters of acoustic emission a few seconds before failure are shown, and the possibility of preventing wire breakage by monitoring the parameters of acoustic emission signals is established. To evaluate the efficiency of the energy supplied to the processing zone, a dynamic model is proposed, with the help of which the processing efficiency is estimated by changing the transmission coefficients in one or several frequency ranges. To explain the situation that occurs in the processing zone with an increase in the concentration of erosion products, the article draws a parallel between electroerosive and laser processing, related to technologies of processing with concentrated flows of energy. Studies have shown that acoustic emission signals can be used to search for rational processing modes and improve automatic control systems for electroerosive equipment.
The Multi-Objective Optimization of Blast Furnace Oxygen Enrichment Rate Based on Optimal Carbon Ratio
Authors: Gao Donghui , Luo Guoping , Wang Yueming , Zhang Guocheng
Published: April 2023

The NSGA-II algorithm was used to establish a multi-objective optimization model for the oxygen enrichment rate of a blast furnace in terms of achieving a lower fuel ratio and higher pulverized coal ratio. The model has the hearth temperature as the constraint condition and the oxygen enrichment rate as the decision variable. The NSGA-II algorithm was used to obtain the Pareto optimal solution of the multi-objective optimization scheme. The prediction effect of the optimization scheme was then tested in industrial experiments. The results show that the optimal setting of the oxygen enrichment rate predicted by the model was 2.70%, which provides an optimal fuel ratio and pulverized coal ratio of 553.86 kg·tHM−1 and 144.58 kg·tHM−1, respectively. In actual production, when the oxygen enrichment rate was set at 2.71%, an optimal fuel ratio and pulverized coal ratio of 553.74 kg·tHM−1 and 148.73 kg·tHM−1 were obtained. The relative error in the oxygen enrichment rate between the model prediction and the actual prediction was 0.003%. The prediction results of the model suggest a reduction in CO2 emissions by 25,770.71 tons per year. The CO2 emission reduction in actual production was approximately 1.09 times the prediction of the model.
Advances in Primary Ironmaking and Steelmaking Processes
Authors: Cavaliere Pasquale
Published: April 2023

In the recent past, ironmaking and steelmaking saw the incorporation of various new processes and technologies that can be operated and organized in different combinations depending on the properties of raw materials and the required quality of the final products [...]
Application of MLR, BP and PCA-BP Neural Network for Predicting FeO in Bottom-Blowing O2-CaO Converter
Authors: Ren Xin , Dong Kai , Feng Chao , Zhu Rong , Wei Guangsheng , Wang Chunyang
Published: April 2023

In order to accurately predict the FeO content of slag in the bottom-blowing O2-CaO process of the dephosphorization converter, multiple linear regression model, backpropagation (BP) neural network model and principal component analysis–backpropagation (PCA-BP) combined with neural network model were established to predict the FeO content of slag. It was found that the PCA-BP combined neural network model has the highest prediction accuracy by using principal component analysis to reduce the dimension of influencing factors of FeO content in slag and eliminate the correlation between input variables. The average absolute error is 1.178%, which is 0.78% lower than that of multiple linear regression model and 0.453% lower than that of multiple linear regression model. When the prediction error range is 3.0%, the prediction hit rate of the model is 96%, and when the prediction error range is 2.0%, the prediction hit rate of the model is 78%. The prediction model has important reference value for actual production.
Relation between Viscosity and Conductivity of CaO-MgO-FeO-Al2O3-SiO2 System for Copper Smelting Slags
Authors: Zhang Lei , Jiang Kaixi , Xie Feng , Lu Diankun
Published: April 2023

The viscosity and conductivity of the smelting slag of copper oxide concentrate are important for reducing the operating temperature. In this study, seven slag samples were prepared by the reductive smelting of copper oxide concentrate with different ferrous oxide contents. The viscosity and conductivity data of these CaO-MgO-FeO-Al2O3-SiO2 samples were measured in the temperature range of 1290~1410 °C. Based on the structural features of aluminosilicate melts, the change and dependency relationships of their viscosity and conductivity were analyzed. The results show that there is a strong tendency to form orthosilicate even when the slag composition is acidic. The formation of fayalite would allow more Al3+ to form pyroxene with the six-coordinated structure. As a result, the polymerization degree and viscosity of the melt will be reduced. The [AlO]45− as a network former will reduce the bonding strength of the structural units, thus reducing the slag viscosity at high temperature. In the experimental range, the logarithm of viscosity of each slag sample has a good linear relationship with its logarithm of conductivity. However, there is no uniform linear equation for these complex slags with wide composition variations. These results have potential guiding significance for the copper smelting process.
A Review on Direct Laser Deposition of Inconel 625 and Inconel 625-Based Composites—Challenges and Prospects
Authors: Zafar Fahad , Emadinia Omid , Conceição João , Vieira Manuel , Reis Ana
Published: April 2023

The direct laser deposition (DLD) process has seen rigorous research in the past two decades due to its ability to directly manufacture products followed by minimal machining. The process input variables play a vital role in determining the properties achieved in the products manufactured by the DLD method. Inconel 625, a nickel-based superalloy with exceptional mechanical performance and corrosion resistance, has been used in critical applications within the aerospace, process, and marine industry. However, its poor machinability and higher load requirements for plastic deformation have been challenging for manufacturers. Therefore, many studies have explored the additive manufacturing of Inconel 625 to overcome these problems. This article focuses on the DLD of Inconel 625 and its composites, presenting the state-of-the-art, drawing a relation among laser processing parameters and resulting material properties, microstructure and phase evolution, and the high-temperature performance of DLD Inconel 625. The paper highlights the areas on which further studies may focus.
Microstructures and High Temperature Tensile Behaviours of Laser Powder Bed Fusion Fabricated Al-Mn-Sc Alloy
Authors: Yan Yuqing , Lu Chengqi , Chen Zhenyu , Zhuo Yuhao , Wang Chuanyang , Jia Qingbo
Published: April 2023

The introduction of Sc/Zr inoculates to aluminium (Al) alloys for laser powder bed fusion (LPBF) provides numerous benefits, including laser processability improvement, solidification microstructure control and mechanical property enhancement. Though great efforts have been put into tailoring the microstructure and room temperature mechanical properties via process parameter optimisations, the potential roles of Sc/Zr inoculate modified Al alloys for high-temperature applications were still underexplored. In this study, the microstructural stability and the elevated temperature tensile behaviours of LPBF-processed Al-Mn-Sc alloy were systematically evaluated. The alloy demonstrated high microstructural stability after both heat treatment and high-temperature tensile testing for up to 573 K. The applied tensile testing temperature and strain rate played significant influences on the elevated temperature tensile properties and deformation behaviours. Unusual intermediate temperature embrittlement (also known as ductility dip) and yield drop behaviours were observed under certain testing temperature and strain rate regimes, and the underlying deformation mechanisms were elucidated in detail. The present study is expected to shed light on future high-performance, high-temperature Al alloy development for the LPBF process.
Impact of Maternal Weight Gain on the Newborn Metabolome
Authors: Guixeres-Esteve Teresa , Ponce-Zanón Francisco , Morales José Manuel , Lurbe Empar , Alvarez-Pitti Julio , Monleón Daniel
Published: April 2023

Pre-pregnancy obesity and excessive gestational weight gain (GWG) appear to affect birth weight and the offspring’s risk of obesity and disease later in life. However, the identification of the mediators of this relationship, could be of clinical interest, taking into account the presence of other confounding factors, such as genetics and other shared influences. The aim of this study was to evaluate the metabolomic profiles of infants at birth (cord blood) and 6 and 12 months after birth to identify offspring metabolites associated with maternal GWG. Nuclear Magnetic Resonance (NMR) metabolic profiles were measured in 154 plasma samples from newborns (82 cord blood samples) and in 46 and 26 of these samples at 6 months and 12 months of age, respectively. The levels of relative abundance of 73 metabolomic parameters were determined in all the samples. We performed univariate and machine-learning analysis of the association between the metabolic levels and maternal weight gain adjusted for mother‘s age, Body Mass Index (BMI), diabetes, diet adherence and infant sex. Overall, our results showed differences, both at the univariate level and in the machine-learning models, between the offspring, according to the tertiles of maternal weight gain. Some of these differences were resolved at 6 and 12 months of age, whereas some others remained. Lactate and leucine were the metabolites with the strongest and longest association with maternal weight gain during pregnancy. Leucine, as well as other significant metabolites, have been associated in the past with metabolic wellness in both general and obese populations. Our results suggest that the metabolic changes associated to excessive GWG are present in children from early life.
Effect of Grape Seed Proanthocyanidins on Fat Metabolism and Adipocytokines in Obese Rats
Authors: Gao Pengxiang , Fang Luoyun , Pan Yucong , Jiang Linshu
Published: April 2023

This study aimed to investigate the effect of Grape Seed Proanthocyanidin (GSP) on fat metabolism and adipocytokines in obese rats. Fifty 5-week-old rats were randomly assigned to five groups (n = 10 per group) and given either a basal diet, a high-fat diet, or a high-fat diet supplemented with GSP (25, 50, and 100 mg/d) per group. The experiment lasted for five weeks, including a one-week adaptation period and a four-week treatment period. At the end of the experimental period, serum and adipose tissue samples were collected and analyzed. Additionally, we co-cultured 3T3-L1 preadipocytes with varying concentrations of GSP to explore its effect on adipocyte metabolism. The results demonstrated that GSP supplementation reduced weight, daily gain, and abdominal fat weight coefficient (p < 0.05). It also decreased levels of glucose, cholesterol (TC) (p < 0.05), triglycerides (TG) (p < 0.05), low-density lipoprotein (LDL), cyclooxygenase-2 (COX-2), and interleukin-6 (IL-6) in adipose tissue. Furthermore, GSP addition caused adipocyte crumpling in vitro and reduced the mRNA expression of COX-2, LEP, and TNF-α in adipocytes in vitro. These findings provide compelling evidence for exploring the role of GSP in the prevention and treatment of obesity and related diseases.
Regulating the Polypyrrole Ion-Selective Membrane and Au Solid Contact Layer to Improve the Performance of Nitrate All-Solid Ion-Selective Electrodes
Authors: Gao Weizhuo , Jing Weixuan , Du Yanrui , Li Zehao , Liu Pengcheng , Han Feng , Zhao Libo , Yang Zhaochu , Jiang Zhuangde
Published: April 2023

With polymerization duration and Au3+ concentration of the electrolyte regulated, a desirable nitrate-doped polypyrrole ion-selective membrane (PPy(NO3−)-ISM) and Au solid contact layer of anticipate surface morphology were obtained, and the performance of nitrate all-solid ion-selective electrodes (NS ISEs) was improved. It was found that the roughest PPy(NO3−)-ISM remarkably increases the actual contact surface area of the PPy(NO3−)-ISMs with nitrate solution, which leads to better adsorption of NO3− ions upon the PPy(NO3−)-ISMs, and produces a larger number of electrons. The most hydrophobic Au solid contact layer avoids the formation of the aqueous layer at the interface between the PPy(NO3−)-ISM and Au solid contact layer, and ensures unimpeded transporting of the produced electrons. The PPy-Au-NS ISE for polymerization duration 1800 s and at Au3+ concentration 2.5 mM of the electrolyte displays an optimal nitrate potential response, including a Nernstian slope of 54.0 mV/dec, LOD of 1.1 × 10−4 M, rapid average response time less than 1.9 s, and long-term stability of more than 5 weeks. This indicates that the PPy-Au-NS ISE is an effective working electrode for the electrochemical determination of NO3− concentration.
A Bi-Directional Acoustic Micropump Driven by Oscillating Sharp-Edge Structures
Authors: Liu Bendong , Qiao Meimei , Zhang Shaohua , Yang Jiahui
Published: April 2023

This paper proposes a bi-directional acoustic micropump driven by two groups of oscillating sharp-edge structures: one group of sharp-edge structures with inclined angles of 60° and a width of 40 μm, and another group with inclined angles of 45° and a width of 25 μm. One of the groups of sharp-edge structures will vibrate under the excitation of the acoustic wave generated with a piezoelectric transducer at its corresponding resonant frequency. When one group of sharp-edge structures vibrates, the microfluid flows from left to right. When the other group of sharp-edge structures vibrates, the microfluid flows in the opposite direction. Some gaps are designed between the sharp-edge structures and the upper surface and the bottom surface of the microchannels, which can reduce the damping between the sharp-edge structures and the microchannels. Actuated with an acoustic wave of a different frequency, the microfluid in the microchannel can be driven bidirectionally by the inclined sharp-edge structures. The experiments show that the acoustic micropump, driven by oscillating sharp-edge structures, can produce a stable flow rate of up to 125 μm/s from left to right, when the transducer was activated at 20.0 kHz. When the transducer was activated at 12.8 kHz, the acoustic micropump can produce a stable flow rate of up to 85 μm/s from right to left. This bi-directional acoustic micropump, driven by oscillating sharp-edge structures, is easy to operate and shows great potential in various applications.
Editorial for the Special Issue on Micro/Nanophotonic Devices in Europe
Authors: Sirleto Luigi , Righini Giancarlo C.
Published: April 2023

Photonics has often been defined as the key technology of the 21st century [...]
Enhancing Wire-EDM Performance with Zinc-Coated Brass Wire Electrode and Ultrasonic Vibration
Authors: Muttamara Apiwat , Nakwong Patittar
Published: April 2023

This study aimed to investigate the performance of zinc-coated brass wire in wire-cut electrical discharge machining (EDM) using an ultrasonic-assisted wire on tungsten carbide. The research focused on the effect of the wire electrode material on the material removal rate, surface roughness, and discharge waveform. Experimental results demonstrated that using ultrasonic vibration improved the material removal rate and reduced surface roughness compared to conventional wire-EDM. Cross-sectional SEM of the white layer and discharge waveform were investigated to explain the phenomena of ultrasonic vibration in the wire-cut EDM process.
Wetting Characteristics of Laser-Ablated Hierarchical Textures Replicated by Micro Injection Molding
Authors: Gao Peng , MacKay Ian , Gruber Andrea , Krantz Joshua , Piccolo Leonardo , Lucchetta Giovanni , Pelaccia Riccardo , Orazi Leonardo , Masato Davide
Published: April 2023

Texturing can be used to functionalize the surface of plastic parts and, in particular, to modify the interaction with fluids. Wetting functionalization can be used for microfluidics, medical devices, scaffolds, and more. In this research, hierarchical textures were generated on steel mold inserts using femtosecond laser ablation to transfer on plastic parts surface via injection molding. Different textures were designed to study the effects of various hierarchical geometries on the wetting behavior. The textures are designed to create wetting functionalization while avoiding high aspect ratio features, which are complex to replicate and difficult to manufacture at scale. Nano-scale ripples were generated over the micro-scale texture by creating laser-induced periodic surface structures. The textured molds were then replicated by micro-injection molding using polypropylene and poly(methyl methacrylate). The static wetting behavior was investigated on steel inserts and molded parts and compared to the theoretical values obtained from the Cassie–Baxter and Wenzel models. The experimental results showed correlations between texture design, injection molding replication, and wetting properties. The wetting behavior on the polypropylene parts followed the Cassie–Baxter model, while for PMMA, a composite wetting state of Cassie–Baxter and Wenzel was observed.
Multiple-Stage Neoproterozoic Magmatism Recorded in the Zhangbaling Uplift of the Northeastern Yangtze Block: Evidence from Zircon Ages and Geochemistry
Authors: Wang Jing , He Jun , Zhao Jingxin , Yang Yizeng , Chen Fukun
Published: April 2023

The Yangtze Block records Neoproterozoic magmatism and sedimentation related to the breakup of Rodinia and is an important piece in the reconstruction of the supercontinent. However, the tectonic setting and position of this block in Rodinia remain a subject of debate. In the present study, we report the zircon U-Pb ages and Hf isotopic composition of zircon and geochemical and Nd-Pb isotopic compositions for meta-volcanic rocks exposed in the Zhangbaling uplift of the NE Yangtze Block. The volcanic rocks, dominated by rhyolite and dacite, belong to the calc-alkaline series and show geochemical characteristics of arc rocks. Zircon U-Pb isotopic ages show that volcanic rocks in the Xileng Formation formed at ca. 790 Ma and ca. 760–700 Ma peaking at ~740 Ma. The late-stage volcanism was widely exposed in the uplift, characterized by a temporal-spatial trend becoming younger southwards. The old volcanic rocks have low initial εNd (−11.0) and εHf (−19.7 to −8.2) values and low Pb isotopic ratios, likely indicating an origin from ancient basement rocks underneath the Yangtze Block. The younger ones, being similar to continental arc andesite in trace element compositions, have relatively high initial εNd (mostly −4.6 to 0.5) and εHf (−0.4 to 8.8) values and high Pb isotopic ratios. These isotopic features point to an origin from the partial melting of juvenile crustal rocks. Sedimentary rocks of the Xileng Formation and the overlying strata also contain numerous zircon grains of ~700 Ma to ~630 Ma. The volcanic rocks in the Zhangbaling uplift might demonstrate long-lasting subduction along the northeastern margin of the Yangtze Block, probably active until ca. 700 Ma.
Effect of Poly(Vinyl Alcohol) Concentration and Chain Length on Polymer Nanogel Formation in Aqueous Dispersion Polymerization
Authors: Kitayama Yukiya , Takigawa Shunsuke , Harada Atsushi
Published: April 2023

Nanotechnology has attracted increasing interest in various research fields for fabricating functional nanomaterials. In this study, we investigated the effect of poly(vinyl alcohol) (PVA) addition on the formation and thermoresponsive properties of poly(N-isopropyl acrylamide)-based nanogels in aqueous dispersion polymerizations. During dispersion polymerization, PVA appears to play three roles: (i) it bridges the generated polymer chains during polymerization, (ii) it stabilizes the formed polymer nanogels, and (iii) it regulates the thermoresponsive properties of the polymer nanogels. By regulating the bridging effect of PVA via changing the PVA concentration and chain length, the size of the obtained polymer gel particles was maintained in the nanometer range. Furthermore, we found that the clouding-point temperature increased when using low-molecular weight PVA. We believe that the knowledge gained in this study regarding the effect of PVA concentration and chain length on nanogel formation will aid in the future fabrication of functional polymer nanogels.
S-Scheme 2D/2D Heterojunction of ZnTiO3 Nanosheets/Bi2WO6 Nanosheets with Enhanced Photoelectrocatalytic Activity for Phenol Wastewater under Visible Light
Authors: Zuo Cheng , Tai Xishi , Jiang Zaiyong , Liu Meifang , Jiang Jinhe , Su Qian , Yan Xueyuan
Published: April 2023

The pollution of phenol wastewater is becoming worse. In this paper, a 2D/2D nanosheet-like ZnTiO3/Bi2WO6 S-Scheme heterojunction was synthesized for the first time through a two-step calcination method and a hydrothermal method. In order to improve the separation efficiency of photogenerated carriers, the S-Scheme heterojunction charge-transfer path was designed and constructed, the photoelectrocatalytic effect of the applied electric field was utilized, and the photoelectric coupling catalytic degradation performance was greatly enhanced. When the applied voltage was +0.5 V, the ZnTiO3/Bi2WO6 molar ratio of 1.5:1 had highest degradation rate under visible light: the degradation rate was 93%, and the kinetic rate was 3.6 times higher than that of pure Bi2WO6. Moreover, the stability of the composite photoelectrocatalyst was excellent: the photoelectrocatalytic degradation rate of the photoelectrocatalyst remained above 90% after five cycles. In addition, through electrochemical analysis, XRD, XPS, TEM, radical trapping experiments, and valence band spectroscopy, we found that the S-scheme heterojunction was constructed between the two semiconductors, which effectively retained the redox ability of the two semiconductors. This provides new insights for the construction of a two-component direct S-scheme heterojunction as well as a feasible new solution for the treatment of phenol wastewater pollution.
Extraction, Purification, and Component Identification of Monoterpene Glycosides from Paeonia suffruticosa Seed Meal
Authors: Wang Fengqin , Hu Fuxia , Zheng Zhenjia , Zhao Haoyan , An Qitong , Wang Zhaosheng
Published: April 2023

Paeonia suffruticosa (P. suffruticosa) seed meal is a byproduct of P. suffruticosa seed processing, which contains bioactive substances such as monoterpene glycosides, and has not been effectively utilized at present. In this study, monoterpene glycosides were extracted from P. suffruticosa seed meal using an ultrasound-assisted ethanol extraction process. The monoterpene glycoside extract was then purified by macroporous resin and identified using HPLC-Q-TOF-MS/MS. The results indicated the following optimal extraction conditions: ethanol concentration, 33%; ultrasound temperature, 55 °C; ultrasound power, 400 W; liquid–material ratio, 33:1; and ultrasound time, 44 min. Under these conditions, the yield of monoterpene glycosides was 121.03 mg/g. The purity of the monoterpene glycosides increased from 20.5% (crude extract) to 71.2% (purified extract) when using LSA-900C macroporous resin. Six monoterpene glycosides (oxy paeoniflorin, isomaltose paeoniflorin, albiflorin, 6′-O-β-D-glucopyranoside albiflorin, paeoniflorin, and Mudanpioside i) were identified from the extract using HPLC-Q-TOF-MS/MS. The main substances were albiflorin and paeoniflorin, and the contents were 15.24 mg/g and 14.12 mg/g, respectively. The results of this study can provide a theoretical basis for the effective utilization of P. suffruticosa seed meal.
Effects of Si/Al Ratio on Passive NOx Adsorption Performance over Pd/Beta Zeolites
Authors: Huang Shasha , Wang Qiang , Shan Yulong , Shi Xiaoyan , Liu Zhongqi , He Hong
Published: April 2023

In the current article, the effect of Si/Al ratio on the NOx adsorption and storage capacity over Pd/Beta with 1 wt% Pd loading was investigated. The XRD, 27Al NMR and 29Si NMR measurements were used to determine the structure of Pd/Beta zeolites. XAFS, XPS, CO-DRIFT, TEM and H2-TPR were used to identify the Pd species. The results showed that the NOx adsorption and storage capacity on Pd/Beta zeolites gradually decreased with the increase of Si/Al ratio. Pd/Beta-Si (Si-rich, Si/Al~260) rarely has NOx adsorption and storage capacity, while Pd/Beta-Al (Al-rich, Si/Al~6) and Pd/Beta-C (Common, Si/Al~25) exhibit excellent NOx adsorption and storage capacity and suitable desorption temperature. Pd/Beta-C has slightly lower desorption temperature compared to Pd/Beta-Al. The NOx adsorption and storage capacity increased for Pd/Beta-Al and Pd/Beta-C by hydrothermal aging treatment, while the NOx adsorption and storage capacity on Pd/Beta-Si had no change.
Cutting-Edge Electrocatalysts for CO2RR
Authors: Jeyachandran Nivetha , Yuan Wangchao , Giordano Cristina
Published: April 2023

A world-wide growing concern relates to the rising levels of CO2 in the atmosphere that leads to devastating consequences for our environment. In addition to reducing emissions, one alternative strategy is the conversion of CO2 (via the CO2 Reduction Reaction, or CO2RR) into added-value chemicals, such as CO, HCOOH, C2H5OH, CH4, and more. Although this strategy is currently not economically feasible due to the high stability of the CO2 molecule, significant progress has been made to optimize this electrochemical conversion, especially in terms of finding a performing catalyst. In fact, many noble and non-noble metal-based systems have been investigated but achieving CO2 conversion with high faradaic efficiency (FE), high selectivity towards specific products (e.g., hydrocarbons), and maintaining long-term stability is still challenging. The situation is also aggravated by a concomitant hydrogen production reaction (HER), together with the cost and/or scarcity of some catalysts. This review aims to present, among the most recent studies, some of the best-performing catalysts for CO2RR. By discussing the reasons behind their performances, and relating them to their composition and structural features, some key qualities for an “optimal catalyst” can be defined, which, in turn, will help render the conversion of CO2 a practical, as well as economically feasible process.