bluuebunny/crossref_metadata_2025 huggingface dataset:
Medium- and High-Entropy Rare Earth Hexaborides with Enhanced Solar Energy Absorption and Infrared Emissivity
Authors: Wang Hongye , Pan Yanyu , Zhang Jincheng , Wang Kaixian , Xue Liyan , Huang Minzhong , Li Yazhu , Yang Fan , Chen Heng
Published: April 2024

The development of a new generation of solid particle solar receivers (SPSRs) with high solar absorptivity (0.28–2.5 μm) and high infrared emissivity (1–22 μm) is crucial and has attracted much attention for the attainment of the goals of “peak carbon” and “carbon neutrality”. To achieve the modulation of infrared emission and solar absorptivity, two types of medium- and high-entropy rare-earth hexaboride (ME/HEREB6) ceramics, (La0.25Sm0.25Ce0.25Eu0.25)B6 (MEREB6) and (La0.2Sm0.2Ce0.2Eu0.2Ba0.2)B6 (HEREB6), with severe lattice distortions were synthesized using a high-temperature solid-phase method. Compared to single-phase lanthanum hexaboride (LaB6), HEREB6 ceramics show an increase in solar absorptivity from 54.06% to 87.75% in the range of 0.28–2.5 μm and an increase in infrared emissivity from 76.19% to 89.96% in the 1–22 μm wavelength range. On the one hand, decreasing the free electron concentration and the plasma frequency reduces the reflection and ultimately increases the solar absorptivity. On the other hand, the lattice distortion induces changes in the B–B bond length, leading to significant changes in the Raman scattering spectrum, which affects the damping constant and ultimately increases the infrared emissivity. In conclusion, the multicomponent design can effectively improve the solar energy absorption and heat transfer capacity of ME/HEREB6, thus providing a new avenue for the development of solid particles.
Data-Driven Design of Nickel-Free Superelastic Titanium Alloys
Authors: Chen Haodong , Ye Wenjun , Hui Songxiao , Yu Yang
Published: April 2024

In this paper, a CatBoost model for predicting superelastic strains of alloys was established by utilizing features construction and selection as well as model filtering and evaluation based on 125 existing data points of superelastic titanium alloys. The alloy compositions of a TiNbMoZrSnTa system were optimized and three nickel-free titanium alloys with potentially excellent superelastic properties were designed using the Bayesian optimization algorithm using a superelastic strain as the optimization target. The experimental results indicated that only Ti-12Nb-18Zr-2Sn and Ti-12Nb-16Zr-3Sn exhibited clear superelasticity due to the absence of relevant information about the alloys’ β stability in the machine learning model. Through experimental optimization of the heat treatment regimens, Ti-12Nb-18Zr-2Sn and Ti-12Nb-16Zr-3Sn ultimately achieved recovery strains of 4.65% after being heat treated at 853 K for 10 min and 3.01% after being heat treated at 1073 K for 30 min, respectively. The CatBoost model in this paper possessed a certain ability to design nickel-free superelastic titanium alloys but it was still necessary to combine it with existing knowledge of material theory for effective utilization.
Effects of Pressure Rollers with Variable Compliance in the Microfinishing Process Utilizing Abrasive Films
Authors: Tandecka Katarzyna , Kacalak Wojciech , Rypina Łukasz , Wiliński Maciej , Wieczorowski Michał , Mathia Thomas G.
Published: April 2024

This article presents a comprehensive investigation into pressure rollers utilized in the microfinishing process, covering aspects such as design, experimental properties, compliance, and finite element simulation. Prototype pressure rollers with unconventional elastomer configurations were designed and analyzed to explore their effectiveness in achieving superior surface finishes. Experimental analysis and finite element simulations were conducted to gain insights into the performance and behavior of these pressure rollers under various loading conditions. This study addresses the validation of constitutive material models used in finite element simulations to ensure accuracy and reliability. The results indicate that the applied material model, validated through experimental analysis, accurately predicts pressure roller behavior. Finite element simulations reveal distinct contact zone patterns and stress distributions across the contact surfaces, highlighting the importance of considering deflection-induced variations in contact behavior. Additionally, the investigation evaluates the effectiveness of different pressure rollers in removing surface irregularities during the microfinishing process. Roller R3 demonstrates the highest efficacy in removing surface peaks, suggesting its potential for achieving superior surface finishes. Overall, this research contributes to the advancement of microfinishing techniques by providing insights into pressure roller design, performance, and behavior, thereby optimizing microfinishing processes to produce high-quality components. The urgency of this study arises from the growing need for exceptional surface finishes in various industrial sectors. With manufacturing industries increasingly pursuing high-precision components boasting flawless surface quality, the significance of microfinishing processes is highlighted.
New Adsorption Materials for Deep Desulfurization of Fuel Oil
Authors: Qiu Xiaoyu , Wang Bingquan , Wang Rui , Kozhevnikov Ivan V.
Published: April 2024

In recent years, due to the rapid growth of mankind’s demand for energy, harmful gases (SOx) produced by the combustion of sulfur-containing compounds in fuel oil have caused serious problems to the ecological environment and human health. Therefore, in order to solve this hidden danger from the source, countries around the world have created increasingly strict standards for the sulfur content in fuel. Adsorption desulfurization technology has attracted wide attention due to its advantages of energy saving and low operating cost. This paper reviewed the latest research progress on various porous adsorption materials. The future challenges and research directions of adsorption materials to meet the needs of clean fuels are proposed.
Sensitivity Analysis of Influencing Factors and Two-Stage Prediction of Frost Resistance of Active-Admixture Recycled Concrete Based on Grey Theory–BPNN
Authors: Fu Chun , Li Ming
Published: April 2024

Sensitivity analysis of influencing factors on frost resistance is carried out in this paper, and a two-stage neural network model based on grey theory and Back Propagation Neural Networks (BPNNs) is established for the sake of predicting the frost resistance of active-admixture recycled concrete quickly and accurately. Firstly, the influence degree of cement, water, sand, natural aggregate, recycled aggregate, mineral powder, fly ash, fiber and air-entraining agent on the frost resistance of active-admixture recycled-aggregate concrete was analyzed based on the grey system theory, and the primary and secondary relationships of various factors were effectively distinguished. Then, the input layer of the model was determined as cement, water, sand, recycled aggregate and air-entraining agent, and the output layer was the relative dynamic elastic modulus. A total of 120 datasets were collected from the experimental data of another author, and the relative dynamic elastic modulus was predicted using the two-stage BPNN prediction model proposed in this paper and compared with the BPNN prediction results. The results show that the proposed two-stage BPNN model, after removing less-sensitive parameters from the input layer, has better prediction accuracy and shorter run time than the BPNN model.
Preparation of Ultrafine Co- and Ni-Coated (Ti,W,Mo,Ta)(C,N) Powders and Their Influence on the Microstructure of Ti(C,N)-Based Cermets
Authors: Zhao Zaiyang , Jia Pengmin , Zhang Yuhui , Ma Lili , Sun Jingjing , Xu Yiping , Wu Yurong
Published: April 2024

The use of metal-coated ceramic powders not only effectively enhances the wettability of the metal–ceramic interface but also promotes a more uniform microstructure in Ti(C,N)-based cermets, which is advantageous for improving their mechanical properties. In this study, ultrafine Co- and Ni-coated (Ti,W,Mo,Ta)(C,N) powders were synthesized via the spray-drying-in-situ carbothermal reduction method. Subsequently, Ti(C,N)-based cermets were effectively fabricated using the as-prepared ultrafine Co- and Ni-coated (Ti,W,Mo,Ta)(C,N) powders. The impact of reaction temperature, heating rate, and isothermal time on the phase and microstructure of prepared powders was analyzed using X-ray diffraction (XRD), scanning electron microscopy (SEM), and transmission electron microscopy (TEM). Additionally, the microstructure of the as-sintered cermets was experimentally investigated. The findings reveal that the complete reduction of Co and Ni metal salts, pre-coated on the surface of (Ti,W,Mo,Ta)(C,N) particles, can be achieved through rapid heating (10 °C/min) in a specific temperature range (600–1000 °C) with an isothermal time of 3 h at a lower reduction temperature (1000 °C). The synthesized powders have only two phases: the (Ti,W,Mo,Ta)(C,N) phase and Co/Ni phase, and no other heterogeneous phases were observed with an oxygen content of 0.261 wt.%. Notably, the conventional core–rim structure was not dominant in the cermets obtained from the prepared Co- and Ni-coated (Ti,W,Mo,Ta)(C,N) powders. Moreover, the heterogeneous segregation effect of the Co/Ni coating on the ultrafine powder particles resulted in a finer microstructure than the traditional cermets with the same composition. However, the grain size is mainly in the range of 0.5–0.8 μm. The weaker residual stresses at the core and rim interfaces and the finer particle distributions could theoretically enhance the toughness of Ti(C,N)-based cermets, simultaneously.
Experimental Study on the Fatigue Crack Propagation Rate of 925A Steel for a Ship Rudder System
Authors: Yu Li , Guo Wenyong , Cao Chenghao , Li Min , Wu Zhe , Wang Te , Chen Hantao , Pan Xinglong
Published: April 2024

The low-temperature fatigue crack propagation rate of 925A steel, as a rudder steel for polar special ships, has a crucial impact on the evaluation of the fatigue strength of polar ships. The purpose of this article is to study the fatigue crack propagation rate of 925A steel under different low-temperature conditions from room temperature (RT) to −60 °C. The material was subjected to fatigue crack propagation tests and stress intensity factor tests. The experimental tests were conducted according to the Chinese Standard of GB/T6398-2017. The results show that as the temperature decreases, the lifespan of 925A increases. Within a certain stress intensity factor, as the temperature decreases, the fatigue crack propagation rate decreases. At −60 °C, it exhibits ductile fracture; within normal polar temperatures, it can be determined that 925A meets the requirements for low-temperature fatigue crack propagation rates in polar regions. However, in some extreme polar temperatures below −60 °C, preventing brittle failure becomes a key focus of fatigue design. Finally, the fatigue crack propagation behavior at the microscale of 925A steel at low temperatures was described using fracture morphology. The experimental data can provide reference for the design of polar ships to further resist low-temperature fatigue and cold brittle fracture.
Effect of Combined Laser Thermal and Shock Wave Effects on the Mechanical and Tribological Properties of Steels
Authors: Bragov Anatoly , Lomunov Andrey , Rusin Evgeny , Gavrilov Gennady , Kurkin Andrey
Published: April 2024

Herein, we present the results of an experimental study on the mechanical properties of Fe-C alloys with different carbon contents (0.2, 0.45, and 0.8%) in a wide range of deformation rates (10−3–103 s−1) and abrasive wear resistance, which underwent combined laser thermal (laser surface hardening—LSH) and laser shock wave (Laser Shock Peening—LSP) processing. The combined treatment modes included a different sequence of exposure to laser thermal and laser-induced shock pulses on the material. The amplitude and duration of laser-induced shock waves were measured using a laser Michelson interferometer. The mechanical properties of steel samples were studied under conditions of uniaxial tension under static loads on a standard universal testing machine, the LR5KPlus, and under dynamic loading, tests were carried out on a specialized experimental complex according to the H. Kolsky method using a split Hopkinson rod. The abrasive wear resistance of hardened surfaces was studied using the Brinell–Haworth method. Studies have shown that the use of a combination of LSH and LSP treatments leads to an increase in both the mechanical properties of steels and abrasive wear resistance compared to traditional laser hardening. It has been established that in the combinations considered, the most effective is laser treatment, in which LSP treatment is applied twice: before and after LSH. Thus, after processing steels using this mode, an increase in the depth of the hardened layer was recorded—by 1.53 times for steel 20, by 1.41 times for steel 45, and by 1.29 times for steel U8—as well as a maximum increase in microhardness values by 22% for steel 20, by 27% for steel 45, and by 13% for U8 steel. The use of this mode made it possible to obtain the maximum strength properties of the studied materials under static and dynamic loading, which is associated with an increase in the volume fraction of the strengthened metal and high microhardness values of the strengthened layer of traditional LSH. The dependences of abrasive wear of the studied steels after various combinations of LSP and LSH impacts were established. It is shown that the greatest wear resistance of the studied steels is observed in the case when the LSH pulse is located between two LSP pulses. In this case, abrasive wear resistance increases by 1.5–2 times compared to traditional LSH.
Study of a Fire-Resistant Plate Containing Fly Ashes Generated from Municipal Waste Incinerator: Fire and Mechanical Characteristics and Environmental Life Cycle Assessment
Authors: Peceño Begoña , Luna-Galiano Yolanda , Varela Fabiola , Alonso-Fariñas Bernabé , Leiva Carlos
Published: April 2024

The recycling of fly ash from municipal solid waste incineration is currently a global issue. This work intends to examine the viability of a novel recycling alternative for fly ashes as a component of fire-resistant plates. To lessen the quantity of heavy metal leaching, the fly ash was utilized after being washed using a water/fly ash ratio of 2 for one hour. Subsequently, an inexpensive, straightforward molding and curing process was used to create a plate, with a composition of 60%wt of MSWI-FA, 30%wt of gypsum, 0.5%wt of glass fiber and 9.5%wt of vermiculite. The plate exhibited high fire resistance. Furthermore, it demonstrated compression, flexural strength and surface hardness slightly lower than the requirements of European Standards. This allows for manufacturing plates with a high washed MSWI-FA content as fire protection in firewalls and doors for homes and commercial buildings. A Life Cycle Assessment was carried out. The case study shows that a 60% substitution of gypsum resulted in an environmental impact reduction of 8–48% for all impact categories examined, except four categories impacts (marine eutrophication, human toxicity (cancer), human non-carcinogenic toxicity and water depletion, where it increased between 2 and 718 times), due to the previous washing of MSWI-FA. When these fly ashes are used as a raw material in fire-resistant materials, they may be recycled and offer environmental advantages over more conventional materials like gypsum.
Novel Probability Density Function of Pad Asperity by Wear Effect over Time in Chemical Mechanical Planarization
Authors: Jeong Seonho , Shin Yeongil , Jeong Jongmin , Jeong Seunghun , Jeong Haedo
Published: April 2024

Chemical mechanical planarization (CMP) reduces film thickness, eliminates step height, and achieves high levels of planarity in semiconductor manufacturing. However, research into its mechanisms is still in progress, and there are many issues to be resolved. To solve problems in CMP, it is necessary to understand the contact phenomenon that occurs at the pad–wafer interface, especially pad asperity. Moreover, understanding the non-uniform distribution of pad asperity, such as height and radius, is essential for predicting the material removal rate (MRR). In this study, based on the existing Greenwood–Williamson (GW) theory and probability density function (PDF), a modified mathematical model that includes changes in asperity distribution was developed and validated experimentally. The contact model proposed in this study included functions that calculated the time-dependent height and radius wear of the pad asperities. Specifically, the experimentally obtained values were compared with the values obtained by the model, and the comparison results were analyzed. Thereby, it was found that the contact model and MRR model considering the change in asperity wear and distribution due to CMP proposed in this study are in better agreement with the experimental results than the existing model, which shows that the MRR can be predicted by a mathematical model using the change in asperity distribution.
The Impact of Platelet-Rich Plasma Application during Cesarean Section on Wound Healing and Postoperative Pain: A Single-Blind Placebo-Controlled Intervention Study
Authors: Barwijuk Michał , Pankiewicz Katarzyna , Gałaś Aleksander , Nowakowski Filip , Gumuła Patrycja , Jakimiuk Artur J. , Issat Tadeusz
Published: April 2024

Background/Objectives: The aim of this study was to evaluate if platelet-rich plasma (PRP) application into the wound during cesarean delivery improves wound healing and reduces pain in the postoperative period. Materials and Methods: A total of 46 patients undergoing cesarean section (CS) were included in this single-blind placebo-controlled intervention study: 23 women in the PRP group and 23 in the placebo group. Every patient was asked to evaluate pain by using the Visual Analogue Scale (VAS) immediately after surgery, as well as 6 and 12 h after the surgery. The use of analgetics was also recorded. The postoperative scar was assessed using the Patient and Observer Scar Assessment Scale (POSAS). Results: There was no case of wound dehiscence in either group. Significant differences between the groups in the scar quality assessment were detected in both patient and doctor POSAS results on days 8, 30 and 90 after surgery in the favor of the PRP group. There was no difference in the pain intensity assessment on the VAS recorded after surgery, but PRP patients required fewer paracetamol doses per day than the control group. Conclusions: PRP application during CS significantly improved wound healing in both short- and long-term assessment. Although it did not influence postoperative pain intensity, it may reduce the use of analgetics after surgery.
Assessing the Feasibility and Efficacy of Pre-Sleep Dim Light Therapy for Adults with Insomnia: A Pilot Study
Authors: Yoon Jihyun , Heo Seok-Jae , Lee Hyangkyu , Sul Eun-Gyeong , Han Taehwa , Kwon Yu-Jin
Published: April 2024

Background: Insomnia is increasingly recognized for its marked impact on public health and is often associated with various adverse health outcomes, including cardiovascular diseases and mental health disorders. The aim of this study was to investigate the efficacy of pre-sleep dim light therapy (LT) as a non-pharmacological intervention for insomnia in adults, assessing its influence on sleep parameters and circadian rhythms. Methods: A randomized, open-label, two-arm clinical trial was conducted over two weeks with 40 participants aged 20–60 years, all of whom had sleep disorders (CRIS, KCT0008501). They were allocated into control and LT groups. The LT group received exposure to warm-colored light, minimizing the blue spectrum, before bedtime. The study combined subjective evaluation via validated, sleep-related questionnaires, objective sleep assessments via actigraphy, and molecular analyses of circadian clock gene expression in peripheral blood mononuclear cells. Baseline characteristics between the two groups were compared using an independent t-test for continuous variables and the chi-squared test for categorical variables. Within-group differences were assessed using the paired t-test. Changes between groups were analyzed using linear regression, adjusting for each baseline value and body mass index. The patterns of changes in sleep parameters were calculated using a linear mixed model. Results: The LT group exhibited significant improvements in sleep quality (difference in difference [95% CI]; −2.00 [−3.58, −0.43], and sleep efficiency (LT: 84.98 vs. control: 82.11, p = 0.032), and an advanced Dim Light Melatonin Onset compared to the control group (approximately 30 min). Molecular analysis indicated a significant reduction in CRY1 gene expression after LT, suggesting an influence on circadian signals for sleep regulation. Conclusions: This study provides evidence for the efficacy of LT in improving sleep quality and circadian rhythm alignment in adults with insomnia. Despite limitations, such as a small sample size and short study duration, the results underscore the potential of LT as a viable non-pharmacological approach for insomnia. Future research should expand on these results with larger and more diverse cohorts followed over a longer period to validate and further elucidate the value of LT in sleep medicine. Trial registration: The trial was registered with the Clinical Research Information Service (KCT0008501).
Endoscopic Gallbladder Drainage: A Comprehensive Review on Indications, Techniques, and Future Perspectives
Authors: Troncone Edoardo , Amendola Rosa , Moscardelli Alessandro , De Cristofaro Elena , De Vico Pasquale , Paoluzi Omero Alessandro , Monteleone Giovanni , Perez-Miranda Manuel , Del Vecchio Blanco Giovanna
Published: April 2024

In recent years, therapeutic endoscopy has become a fundamental tool in the management of gallbladder diseases in light of its minimal invasiveness, high clinical efficacy, and good safety profile. Both endoscopic transpapillary gallbladder drainage (TGBD) and endoscopic ultrasound (EUS)-guided gallbladder drainage (EUS-GBD) provide effective internal drainage in patients with acute cholecystitis unfit for cholecystectomy, avoiding the drawbacks of external percutaneous gallbladder drainage (PGBD). The availability of dedicated lumen-apposing metal stents (LAMS) for EUS-guided transluminal interventions contributed to the expansion of endoscopic therapies for acute cholecystitis, making endoscopic gallbladder drainage easier, faster, and hence more widely available. Moreover, EUS-GBD with LAMS opened the possibility of several cholecystoscopy-guided interventions, such as gallstone lithotripsy and clearance. Finally, EUS-GBD has also been proposed as a rescue drainage modality in malignant biliary obstruction after failure of standard techniques, with encouraging results. In this review, we will describe the TBGD and EUS-GBD techniques, and we will discuss the available data on clinical efficacy in different settings in comparison with PGBD. Finally, we will comment on the future perspectives of EUS-GBD, discussing the areas of uncertainty in which new data are more strongly awaited.
Beyond Weight Loss: A Comprehensive Review of Pregnancy Management following Bariatric Procedures
Authors: Huluță Iulia , Apostol Livia-Mihaela , Botezatu Radu , Panaitescu Anca Maria , Gică Corina , Sima Romina-Marina , Gică Nicolae , Nedelea Florina Mihaela
Published: April 2024

The increasing prevalence of bariatric surgery among women of childbearing age raises critical questions about the correct management of pregnancy following these procedures. This literature review delves into the multifaceted considerations surrounding pregnancy after bariatric surgery, with a particular focus on the importance of preconception counselling, appropriate nutrition assessment, and the necessity of correct folic acid supplementation. Key areas of investigation include nutrient absorption challenges, weight gain during pregnancy, and potential micronutrient deficiencies. Examining the relationship between bariatric surgery and birth defects, particularly heart and musculoskeletal issues, uncovers a twofold increase in risk for women who underwent surgery before pregnancy, with the risk emphasized before folic acid fortification. In contrast, a nationwide study suggests that infants born to mothers with bariatric surgery exhibit a reduced risk of major birth defects, potentially associated with improved glucose metabolism. In addition, this review outlines strategies for managing gestational diabetes and other pregnancy-related complications in individuals with a history of bariatric surgery. By synthesizing existing literature, this paper aims to provide healthcare providers with a comprehensive framework for the correct management of pregnancy in this unique patient population, promoting the health and well-being of both mother and child.
Additive Manufacturing for Rapid Sand Casting: Mechanical and Microstructural Investigation of Aluminum Alloy Automotive Prototypes
Authors: Cecchel Silvia , Cornacchia Giovanna
Published: April 2024

The automotive industry is undergoing a rapid evolution to meet today’s challenges; therefore, continuous innovation and product development are needed. Validation tests on prototypes play a crucial role in moving new components into industrial production. There is also a pressing need for faster prototyping processes. In this context, rapid sand casting (RSC), based on additive manufacturing technology, offers a promising solution for a quick production of sand molds. While this technology is already employed in the industry, the need to deepen the general understanding of its impact on the casting properties is still a relevant item. In this study, different geometries of automotive prototypes made of aluminum EN AC 42100-T6 alloy were experimentally analyzed. Microstructural examinations, tensile tests, and fractography and porosity analyses were conducted. The findings demonstrate the considerable potential of RSC, giving, in general, high mechanical properties. A comparative analysis with prototypes produced through traditional sand casting revealed similar results, with RSC exhibiting superior yield strength and stress at brake. However, both technologies revealed a reduced elongation percentage, as expected. Future efforts will focus on standardizing the RSC process to enhance ductility levels.
Study on Recovery of Lithium from Lithium-Containing Aluminum Electrolyte
Authors: Ji Rui , Cui Xi , Zhang Wenzheng , Wang Shichao , Yang Mingliang , Qu Tao
Published: April 2024

The current process of recovering lithium from wasted aluminum electrolyte mostly entails extracting lithium from lithium-containing aluminum electrolyte by acid leaching and dissipation. Aiming at the disadvantages of the existing treatment method, such as the long process flow, environmental pollution, poor working environment, etc., we propose a new technology to extract lithium from the wasted aluminum electrolyte and systematically investigate the effects of raw material particle size, holding time, temperature and other factors on the recovery of lithium. The results show that the better process conditions for the recovery of lithium are as follows: the raw material particle size is 75~150 μm, the additive is CaCl2, the mass ratio of calcium chloride to lithium-containing aluminum electrolyte is 3:5, the reaction temperature is 1473 K, and the holding time is 3 h. After the product of the reaction is crushed and leaching is carried out by using deionized water (pH = 6.8), the temperature of the leaching is 368 K, the leaching time is 3 h, and the solid–liquid ratio is 1/3, and the leaching rate of Li can be up to 75.1%. In addition, the purity of the recovered AlF3 is more than 92.7%. This process realizes the comprehensive and efficient use of lithium-containing aluminum electrolyte and provides a new idea for the development of lithium extraction technology from lithium-containing aluminum electrolyte.
A Comprehensive Review of Fatigue Strength in Pure Copper Metals (DHP, OF, ETP)
Authors: Jiménez-Ruiz Eduardo , Lostado-Lorza Rubén , Berlanga-Labari Carlos
Published: April 2024

Due to their exceptional electrical and thermal conductivity properties, high-purity copper (Cu-DHP) and copper alloys of similar composition, such as electrolytic tough-pitch (ETP), oxygen-free electronic (OFE) and oxygen-free (OF), have often been used in the manufacture of essential components for the electrical, electronic and power generation industries. Since these components are subject to cyclic loads in service, they can suffer progressive structural damage that causes failure due to fatigue. The purpose of this review is to examine the most relevant aspects of mechanical fatigue in Cu-DHP, ETP, OFE and OF. The impact of many factors on fatigue strength (Se), including the frequency, temperature, chemical environment, grain size, metallurgical condition and load type, were analyzed and discussed. Stress–life (S-N) curves under zero mean stress (σm = 0) were found for high-cycle fatigue (HCF). For non-zero mean stress (σm ≠ 0), stress curves were based on a combination of Gerber, Soderberg and ASME elliptic failure criteria. Stress–life (S-N) curves were also developed to correlate fatigue strength (Se) with stress amplitude (σa), yield strength (Syp) and ultimate strength (Sut). Finally, for low-cycle fatigue (LCF), strain–life (ε-N) curves that establish a relationship between the number of cycles to failure (N) and total strain amplitude (εplastic) were determined. Hence, this review, as well as the proposed curves, provide valuable information to understand fatigue failure for these types of materials.
Examining the Pathogenesis of MAFLD and the Medicinal Properties of Natural Products from a Metabolic Perspective
Authors: Fu Yansong , Wang Zhipeng , Qin Hong
Published: April 2024

Metabolic-associated fatty liver disease (MAFLD), characterized primarily by hepatic steatosis, has become the most prevalent liver disease worldwide, affecting approximately two-fifths of the global population. The pathogenesis of MAFLD is extremely complex, and to date, there are no approved therapeutic drugs for clinical use. Considerable evidence indicates that various metabolic disorders play a pivotal role in the progression of MAFLD, including lipids, carbohydrates, amino acids, and micronutrients. In recent years, the medicinal properties of natural products have attracted widespread attention, and numerous studies have reported their efficacy in ameliorating metabolic disorders and subsequently alleviating MAFLD. This review aims to summarize the metabolic-associated pathological mechanisms of MAFLD, as well as the natural products that regulate metabolic pathways to alleviate MAFLD.
Metabolomic Analysis Reveals the Association of Severe Bronchopulmonary Dysplasia with Gut Microbiota and Oxidative Response in Extremely Preterm Infants
Authors: Chiu Chih-Yung , Chiang Ming-Chou , Chiang Meng-Han , Lien Reyin , Fu Ren-Huei , Hsu Kai-Hsiang , Chu Shih-Ming
Published: April 2024

Bronchopulmonary dysplasia (BPD) is a chronic lung disease mainly affecting premature infants needing ventilation or oxygen for respiratory distress. This study aimed to evaluate the molecular linkages for BPD in very and extremely preterm infants using a metabolomics-based approach. A case-control study of enrolling preterm infants born before 32 weeks gestational age (GA) was prospectively performed. These preterm infants were subsequently stratified into the following two groups for further analysis: no or mild BPD, and moderate or severe BPD based on the 2019 NICHD criteria. Urinary metabolomic profiling was performed using 1H-Nuclear magnetic resonance (NMR) spectroscopy coupled with partial least squares discriminant analysis (PLS-DA) at a corrected age of 6 months. Metabolites significantly differentially related to GA and BPD severity were performed between groups, and their roles in functional metabolic pathways were also assessed. A total of 89 preterm infants born before 32 weeks gestation and 50 infants born at term age (above 37 completed weeks’ gestation) served as controls and were enrolled into the study. There were 21 and 24 urinary metabolites identified to be significantly associated with GA and BPD severity, respectively (p < 0.05). Among them, N-phenylacetylglycine, hippurate, acetylsalicylate, gluconate, and indoxyl sulfate were five metabolites that were significantly higher, with the highest importance in both infants with GA < 28 weeks and those with moderate to severe BPD, whereas betaine and N,N-dimethylglycine were significantly lower (p < 0.05). Furthermore, ribose and a gluconate related pentose phosphate pathway were strongly associated with these infants (p < 0.01). In conclusion, urinary metabolomic analysis highlights the crucial role of gut microbiota dysbiosis in the pathogenesis of BPD in preterm infants, accompanied by metabolites related to diminished antioxidative capacity, prompting an aggressive antioxidation response in extremely preterm infants with severe BPD.
Compliance and Kinetostatics of a Novel 2PRS-2PSS Compliant Parallel Micromanipulator: Modeling and Analysis
Authors: Ren Jun , Jiang Hui
Published: April 2024

A novel 2PRS-2PSS (P represents the prismatic pair, R represents the revolute hinge, S represents the spherical hinge) compliant parallel micromanipulator with two translational DOFs and two rotational DOFs is presented, and its compliance model and kinetostatic model are sequentially developed and analyzed. Initially, an analytical model used to describe the compliance of this micromanipulator was developed using the compliance matrix method (CMM). Through a comparison with finite element analysis, the accuracy of this analytical model is confirmed, and the influence of various dimensional and structural parameters on the compliance behavior is investigated. Subsequently, the micromanipulator is treated as an equivalent spring system, allowing for the derivation of its governing equation based on the established compliance model. From this equation, a kinetostatic model relating input forces to output displacements is derived. Validation of this model is performed by comparing analytical results with finite element simulations under specific motion trajectories, revealing a maximum relative error of 6.18%. This close agreement verifies the accuracy of the kinetostatic model. Finally, the impact of the parameters of the flexure hinge on the mapping matrix is examined to offer insights into minimizing undesired displacements, providing valuable guidance for optimizing the micromanipulator’s performance.
Recent Advances in Carbon Nanotube Utilization in Perovskite Solar Cells: A Review
Authors: Asghar Usman , Qamar Muhammad Azam , Hakami Othman , Ali Syed Kashif , Imran Mohd , Farhan Ahmad , Parveen Humaira , Sharma Mukul
Published: April 2024

Due to their exceptional optoelectronic properties, halide perovskites have emerged as prominent materials for the light-absorbing layer in various optoelectronic devices. However, to increase device performance for wider adoption, it is essential to find innovative solutions. One promising solution is incorporating carbon nanotubes (CNTs), which have shown remarkable versatility and efficacy. In these devices, CNTs serve multiple functions, including providing conducting substrates and electrodes and improving charge extraction and transport. The next iteration of photovoltaic devices, metal halide perovskite solar cells (PSCs), holds immense promise. Despite significant progress, achieving optimal efficiency, stability, and affordability simultaneously remains a challenge, and overcoming these obstacles requires the development of novel materials known as CNTs, which, owing to their remarkable electrical, optical, and mechanical properties, have garnered considerable attention as potential materials for highly efficient PSCs. Incorporating CNTs into perovskite solar cells offers versatility, enabling improvements in device performance and longevity while catering to diverse applications. This article provides an in-depth exploration of recent advancements in carbon nanotube technology and its integration into perovskite solar cells, serving as transparent conductive electrodes, charge transporters, interlayers, hole-transporting materials, and back electrodes. Additionally, we highlighted key challenges and offered insights for future enhancements in perovskite solar cells leveraging CNTs.
Rb–Sr Pyrite Dating and S–Pb Isotopes in the Fang’an Gold Deposit, Wuhe Area, Eastern Anhui Province
Authors: Wang Ying , Shi Ke , Zhong Ze , Ren Shenglian , Wang Juan , Zhang Yan , Song Chuanzhong , Zhang Gang , Ren Fangyu
Published: April 2024

The Fang’an gold deposit in the Wuhe area, Anhui Province, is located in the area adjacent to the Bengbu Uplift and Wuhe Platform Depression in the southeastern part of North China. This study aimed to determine the deposit’s mineralization age and the source of its metallogenic materials and mineralization processes through investigations into its geological characteristics, Rb–Sr isotopes, and S–Pb isotopes. The orebodies of the Fang’an gold deposit in the Neoarchean Xigudui Formation primarily exhibit a vein-type structure. The ore-forming process can be divided into four stages: (i) the quartz stage (Py1); (ii) the quartz–pyrite stage (Py2); (iii) the polymetallic sulfide stage (Py3); and (iv) the carbonate stage. Of these, the main mineralization stage is also the main period in which gold mineralization occurs. In situ sulfur isotope results of pyrite (Py1 to Py3) in the first three mineralization stages, suggesting a contribution of sulfur from crust–mantle magmatic fluids. The δ34S values for Py2 (average 5.51‰) are higher than Py1 (average 4.45‰) and showed that the magmatic fluids mixed with meteoric waters. The δ34S values for Py3 (average 5.18‰) are lower than Py2 (average 5.51‰), revealing that it related fluid immiscibility. The lead isotopic compositions of sulfides within the ores possessed 206Pb/204Pb ratios ranging from 16.759 to 16.93, 207Pb/204Pb ratios ranging from 15.311 to 15.402, and 208Pb/204Pb ratios ranging from 37.158 to 37.548. These lead data were plotted close to the Xigudui Formation, relatively distant from the Mesozoic granites, indicating that the Xigudui Formation was the source of lead for the Late Mesozoic ores of the deposit. Taken together, due to the degassing of mantle-derived magma in the shallow parts of the crust, it can be determined that the sources of ore-forming sulfur and lead were crust–mantle magmatic activities in the Wuhe area. Rb–Sr dating of pyrite from Fang’an gold deposit reveals that the mineralization occurred at 126.89 ± 0.58 Ma. Considering the previous research into the dating of magmatic rocks in the Wuhe area, we propose that the genesis of the Fang’an gold deposit is closely associated with magmatic activities in the area at around 130 Ma.
Fingerprinting Ceramics from the Chalcolithic Santa Vitória Enclosure (SW Iberia)
Authors: Marques Rosa , Rodrigues Ana Luisa , Russo Dulce , Gméling Katalin , Valera António C. , Dias Maria I. , Prudêncio Maria I. , Basílio Ana Catarina , Fernandes Paula G. , Ruiz Francisco
Published: April 2024

The Santa Vitória Chalcolithic site (southern Portugal) prompts several questions related to the provenance and production technology of artefacts. Archaeological ceramics from two sections of Ditch 1 of the Santa Vitória site were studied by neutron activation analysis and X-ray diffraction for the first time, with the main goal of contributing to the contextualization of the artefacts and better understanding their production processes/technologies and the provenance of raw materials. The results point to a local production of ceramics, since their mineral phases reflect the geological contexts around the archaeological site. The mineralogical assemblage indicates a firing temperature below 850 °C. Iron is the better discriminator of ceramics from both sections, which could be related to the addition of different proportions of temper grains during the ceramics’ production. Although trace elements do not serve as discriminating geochemical indicators for the analyzed samples, they do imply a slightly higher heterogeneity in the composition of the ceramic paste from section 2. The negative Eu anomaly found in two samples is in accordance with the lower contents of Na2O, related to plagioclase weathering. Detailed studies on ceramics and potential raw materials are foreseen to assist in discussing the role of this Chalcolithic archaeological site at a regional level.
Construction and Demolition Waste Ballast as a Pozzolanic Addition in Binary Cements: Characterization and Thermodynamic Stability
Authors: Yagüe-García Santiago , García-Giménez Rosario
Published: April 2024

The use of raw materials from the recovery of construction waste is frequent. In this study, the waste is obtained from degraded railway ballast, made up of siliceous minerals. This material is added directly to the mixtures to replace part of the cement, forming a good quality cementitious product. The pozzolanic reaction is studied within the waste/lime system in a solid phase and water system for one year. Reaction products such as stratlingite, layered double hydroxide-type compounds, hydrated tetracalcic aluminate, and gels appear. The formation of stratlingite and gels was favored throughout the reaction. The reaction was monitored, calculating the saturation index.
Zonal Geochemistry and Elasticity Characteristics of Gallium- and Lithium-Rich No. 6 Coalbed in the Haerwusu Mine, North China
Authors: Fu Jiannan , Chen Tongjun , Cui Fan
Published: April 2024

This paper presents the zonal geochemistry and elasticity characteristics of gallium- and lithium-rich No. 6 coalbed in the Haerwusu mine and discusses interpretation methodologies of coal-hosted gallium and lithium resources using lab-measured samples and field-measured wireline logs. The results demonstrate that both coal-composition-based and elastic-parameter-based classifications yield similar results, categorizing the coalbed into subzones related to coal quality. Material compositions, elastic properties, critical metals, and host minerals exhibit zonal distribution characteristics within the ultrathick No. 6 coalbed. Three-class classifications significantly enhance correlations among host minerals, elastic parameters, and critical metals, albeit with differing trends among classes. In classes II and III (ultralow- and low-ash-yield coals), boehmite and kaolinite primarily host gallium and lithium, respectively. In class I (medium-ash-yield coal), gallium is associated with kaolinite, while lithium lacks specific mineral associations. Constrained by wireline logs, a rock physics modeling strategy is proposed to link mesoscale coal compositions to macroscale elastic responses. Moreover, explicit correlations between host minerals and critical metals are established, connecting macroscale elastic responses to microscale gallium and lithium enrichments and exploring interpretation methods of coal-hosted critical metals. Preferred lithium interpretation methods include compositional ternary plots and elastic parameter cross plots, while preferred gallium interpretation methods involve boehmite-gallium and elastic parameter-gallium fitting. These findings may contribute to understanding the enrichment mechanisms and interpretation technologies of coal-hosted critical metals in ultrathick low-rank coalbeds.
Effect of Bulk Nanobubbles on the Flocculation and Filtration Characteristics of Kaolin Using Cationic Polyacrylamide
Authors: Li Yihong , Ma Guangxi , Bilal Muhammad , Sha Jie , Bu Xiangning
Published: April 2024

This study investigated the influence of bulk nanobubbles (NBs) on the flocculation and filtration behavior of kaolin suspensions treated with cationic polyacrylamide (CPAM). Traditionally, flocculation relies on bridging mechanisms by polymers like CPAM. The present work examines the possibility of combining NBs with CPAM to achieve more efficient kaolin separation. The settling behavior of kaolin suspensions with and without bulk nanobubbles was compared. The results with 2 mL CPAM and 300 s settling time revealed that bulk NBs significantly enhanced flocculation efficiency, with supernatant zone height reductions exceeding 50% compared to CPAM alone, indicating a faster settling rate resulting from bulk NBs. This improvement in the settling rate is attributed to NBs’ ability to reduce inter-particle repulsion (as evidenced by a shift in zeta potential from −20 mV to −10 mV) and bridge kaolin particles, complementing the action of CPAM. Additionally, the study demonstrated that bulk NBs improved dewatering characteristics by lowering the medium resistance and specific cake resistance during filtration. These findings pave the way for the utilization of bulk NBs as a novel and efficient strategy for kaolin separation in mineral processing, potentially leading to reduced processing times and lower operational costs.
QSAR Study, Molecular Docking and Molecular Dynamic Simulation of Aurora Kinase Inhibitors Derived from Imidazo[4,5-b]pyridine Derivatives
Authors: Tian Yang-Yang , Tong Jian-Bo , Liu Yuan , Tian Yu
Published: April 2024

Cancer is a serious threat to human life and social development and the use of scientific methods for cancer prevention and control is necessary. In this study, HQSAR, CoMFA, CoMSIA and TopomerCoMFA methods are used to establish models of 65 imidazo[4,5-b]pyridine derivatives to explore the quantitative structure-activity relationship between their anticancer activities and molecular conformations. The results show that the cross-validation coefficients q2 of HQSAR, CoMFA, CoMSIA and TopomerCoMFA are 0.892, 0.866, 0.877 and 0.905, respectively. The non-cross-validation coefficients r2 are 0.948, 0.983, 0.995 and 0.971, respectively. The externally validated complex correlation coefficients r2pred of external validation are 0.814, 0.829, 0.758 and 0.855, respectively. The PLS analysis verifies that the QSAR models have the highest prediction ability and stability. Based on these statistics, virtual screening based on R group is performed using the ZINC database by the Topomer search technology. Finally, 10 new compounds with higher activity are designed with the screened new fragments. In order to explore the binding modes and targets between ligands and protein receptors, these newly designed compounds are conjugated with macromolecular protein (PDB ID: 1MQ4) by molecular docking technology. Furthermore, to study the nature of the newly designed compound in dynamic states and the stability of the protein-ligand complex, molecular dynamics simulation is carried out for N3, N4, N5 and N7 docked with 1MQ4 protease structure for 50 ns. A free energy landscape is computed to search for the most stable conformation. These results prove the efficient and stability of the newly designed compounds. Finally, ADMET is used to predict the pharmacology and toxicity of the 10 designed drug molecules.