bluuebunny/crossref_metadata_2025 huggingface dataset:
Agroecological Risk Assessment Based on Coupling of Water and Land Resources—A Case of Heihe River Basin
Authors: Yu Jiashan , Zhou Jun , Zhao Jing , Chen Ran , Yao Xueqi , Luo Xiaomin , Jiang Sijia , Wang Ziyang
Published: March 2023

In the arid zone of northwest China, the Heihe River Basin (HRB), as a typical inland river basin, has a fragile regional ecological environment, obvious ecological degradation characteristics, and extremely serious problems in the utilization of agricultural land resources. Meanwhile, the shortage of water resources, the low reduction of land quality, and excessive agricultural activities have greatly increased the local water and land pressure. In this paper, firstly, using the Malmquist DEA model and coupling coordination degree model, the agroecological risk assessment system on account of the coupling of water and land resources (WLR) is constructed. Secondly, taking HRB from 1995 to 2020 as an example, we carry out spatial correlation analysis based on the degree of risk-correlated WLR. Thirdly, we analyze the evolution process and spatial correlation of ecological risk of agricultural WLR in the HRB at the county scale, then we conclude and put forward policy suggestions for improvement. The results show that: (1) On the whole, the average ecological risk of agricultural water resources in the HRB from 1995 to 2020 was 0.933, indicating that the risk was declining; the average ecological risk of agricultural land resources in the HRB from 1995 to 2020 was 0.938, indicating that the risk was declining also. (2) The degree of ecological risk coupling and coordination of agricultural soil and water resources upstream of the HRB is on the rise, while that in the middle and lower reaches is on the decline. (3) Through panel model analysis, the matching suitability of WLR drives agroecological risk. The correlation between them is positive. In conclusion, this method can effectively evaluate the agroecological risk of WLR and provide technical support for agricultural production and management in arid areas.
Equity Analysis of the Green Space Allocation in China’s Eight Urban Agglomerations Based on the Theil Index and GeoDetector
Authors: Zheng Xueyan , Zhu Minghui , Shi Yan , Pei Hui , Nie Wenbin , Nan Xinge , Zhu Xinyi , Yang Guofu , Bao Zhiyi
Published: March 2023

An urban agglomeration is a highly developed spatial area formed by integrated cities. While previous studies have analyzed green space allocation at the provincial and city scales, there is insufficient information on green space allocation in urban agglomerations. For this research, a database of green spaces in eight urban agglomerations (133 cities) in China from 2002 to 2019 was constructed to better understand the equity of green space distribution among land resources. A green space equity index (GEI) was established based on the Theil index and combined with GeoDetector to analyze the differences in urban agglomeration green spaces. The main conclusions are as follows: The sum of the GEI of China’s urban agglomerations has increased significantly, rising from 3.74 in 2002 to 6.34 in 2019. The GEI value for each of the eight urban agglomerations was kept under 0.01. Polarized development has occurred within urban agglomeration cities, and the allocation of green space in megacities is relatively weak, especially in the more economically developed Yangtze River Delta and Guanzhong urban agglomerations. The average temperature, humidity, and precipitation have dominant influences in determining the GEI values. This paper provides a new perspective on the management and allocation of urban agglomeration green spaces.
Prebiotic Chemistry of Phosphite: Mild Thermal Routes to Form Condensed-P Energy Currency Molecules Leading Up to the Formation of Organophosphorus Compounds
Authors: Gull Maheen , Feng Tian , Cruz Harold A. , Krishnamurthy Ramanarayanan , Pasek Matthew A.
Published: March 2023

The in-fall of meteorites and interstellar dust particles during the Hadean–Archean heavy bombardment may have provided the early Earth with various reduced oxidation state phosphorus compounds and minerals, including phosphite (HPO32−)([Pi(III)]). The ion phosphite ([Pi(III)])has been postulated to be ubiquitous on the early Earth and consequently could have played a role in the emergence of organophosphorus compounds and other prebiotically relevant P species such as condensed P compounds, e.g., pyrophosphite ([PPi(III)]) and isohypophosphate ([PPi(III–V)]). In the present study, we show that phosphite ([Pi(III)]) oxidizes under mild heating conditions (e.g., wet–dry cycles and a prebiotic scenario mimicking a mildly hot-evaporating/drying pool on the early Earth at 78–83 °C) in the presence of urea and other additives, resulting in changes to orthophosphate ([Pi(V)]) alongside the formation of reactive condensed P compounds (e.g., pyrophosphite ([PPi(III)]) and isohypophosphate ([PPi(III–V)])) through a one-pot mechanism. Additionally, we also show that phosphite ([Pi(III)]) and the condensed P compounds readily react with organics (nucleosides and organic alcohol) to form organophosphorus compounds.
Management Food Waste in Municipality Schools: An Analysis from a Circular Economy Perspective
Authors: Sehnem Simone , Godoi Lucia , Simioni Flavio , Martins Cristina , Soares Sandro Vieira , de Andrade Guerra José Baltazar Salgueirinho Osório , Provensi Tais
Published: March 2023

Background: Food waste is a situation that triggers certain controversy, considering that there is still a significant number of people who do not have access to healthy and nutritious food every day. The management of food leftovers from school lunches depends on the creation of measurement mechanisms. Thus, current characteristics of schools should be identified in order to mitigate and better manage these leftovers. This study addresses this gap, that is, it seeks to understand how food waste management is carried out in schools from a circular economy perspective. Methods: Focusing on the management of school lunches in municipal schools, this study aims to build an inductive interpretive theory in order to understand how schools promote food waste management. Results: Loss estimates and their monetization were identified and explained, and alternatives for waste recovery using the ReSOLVE framework were proposed. Conclusions: Therefore, it was assumed that the perspective of circularity is a possible and viable way to manage food waste in school lunches. Stakeholder engagement and awareness raising become necessary premises for success in the food circularity journey.
6,6′-Di-(8″-quinoline)-2,2′-bipyridine Cobalt(II) Complex
Authors: Li Yuwei , Tong Lianpeng
Published: March 2023

This short note describes the synthesis of a novel compound, 6,6′-di-(8″-quinoline)-2,2′-bypyridine (2), that bears a bipyridyl backbone and quinoline donors. Compound 2 coordinates with a cobalt(II) ion in a tetradentate manner and affords the complex [CoII(2)(TfO)2], whose molecular structure has been identified by single crystal X-ray diffraction crystallographic analysis. The coordination features of 2 were compared with those of 2,2′:6′,2″:6″,2‴-quaterpyridine (qtpy, 1), a well-studied tetradentate polypyridine ligand. Compound 2 presents a new example of tetradentate chelators for 3d metal ions.
Microstructure and Mechanical Properties of Laser-Welded Joints between DP590 Dual-Phase Steel and 304 Stainless Steel with Preset Nickel Coating
Authors: Zhang Hua , Xu Jiahui , Hao Desheng , Esmail Othman Mohammed Ali Othman
Published: March 2023

Dissimilarities in metal laser welding lead to brittleness in welded joints due to differences in the thermophysical and chemical properties between dissimilar base materials. To overcome such brittleness, the addition of a preset coating onto the base materials as an interlayer is a method for attaining reliable welded joints. Nd:YAG laser butt welding of DP590 dual-phase steel and 304 stainless, both with a thickness of 1 mm, was performed with a preset nickel coating as an interlayer using an electroplating process. The relationship between the microstructure and the mechanical properties of the welded joints was researched, the microstructure and composition of the weldment were analyzed, and the microhardness, tensile strength and corrosion resistance were tested. The results showed that the preset nickel coating increased the content of Ni element in the welded joints, which is beneficial to the formation of lath martensite. The average hardness of the welded joints increased by 12%, and the tensile strength was higher than 370 MPa. The corrosion rate of the welded joints can be slowed down, and the corrosion resistance can be improved by increasing the nickel coating.
Recent Advances of GFRP Composite Cross Arms in Energy Transmission Tower: A Short Review on Design Improvements and Mechanical Properties
Authors: Syamsir Agusril , Ean Lee-Woen , Asyraf Muhammad , Supian Abu , Madenci Emrah , Özkılıç Yasin , Aksoylu Ceyhun
Published: March 2023

Currently, pultruded glass fibre-reinforced polymer (pGFRP) composites have been extensively applied as cross-arm structures in latticed transmission towers. These materials were chosen for their high strength-to-weight ratio and lightweight characteristics. Nevertheless, several researchers have discovered that several existing composite cross arms can decline in performance, which leads to composite failure due to creep, torsional movement, buckling, moisture, significant temperature change, and other environmental factors. This leads to the composite structure experiencing a reduced service life. To resolve this problem, several researchers have proposed to implement composite cross arms with sleeve installation, an addition of bracing systems, and the inclusion of pGFRP composite beams with the core structure in order to have a sustainable composite structure. The aforementioned improvements in these composite structures provide superior performance under mechanical duress by having better stiffness, superiority in flexural behaviour, enhanced energy absorption, and improved load-carrying capacity. Even though there is a deficiency in the previous literature on this matter, several established works on the enhancement of composite cross-arm structures and beams have been applied. Thus, this review articles delivers on a state-of-the-art review on the design improvement and mechanical properties of composite cross-arm structures in experimental and computational simulation approaches.
Study on Modification and Mechanism of Construction Waste to Solidified Silt
Authors: Shi Yannan , Weng Haoxuan , Yu Jiongqi , Gong Yongfan
Published: March 2023

A large amount of silt may be produced in river and lake regulation. It not only occupies land but also pollutes the environment. Therefore, it is urgent to seek effective disposal and utilization methods. Based on the problems of poor stability of stabilized soil and its tendency to soften easily in water, as well as its low strength with low curing agent dosage, this paper proposes a method to improve stabilized soil’s solidification effect by adding materials such as cement, lime, fly ash, triethanolamine, sodium hydroxide, sodium silicate, etc., while mixing different grain diameters and quantities of building waste materials and ordinary sand. Using construction waste and ordinary sand as a comparative test, the curing mechanism of construction waste debris on the mechanical properties, permeability, and microstructure of solidified sludge was studied through unconfined compression tests, dry and wet cycle tests, permeability tests, and micro-structure tests such as XRD, MIP, and SEM. The test results show that the strength increases 8.5%~72.1% by adding building waste materials, and it grew with the increase in particle size and amount. It reduced the content of large pore size of solidified sediment and optimized the internal pore structure. At the same time, it formed a new structure filled by rigid skeleton material. Thus, it improved its unit section stress, built up the curing effect and water stability. The findings of this study can be used to modify solidified silt to improve stability and compaction characteristics.
Characterization of Pore Size Distribution and Water Transport of UHPC Using Low-Field NMR and MIP
Authors: Xiong Xin-Rui , Wang Jun-Yan , She An-Ming , Lin Jian-Mao
Published: March 2023

Water transport is vital for the durability of ultra-high performance concrete (UHPC) in engineering, but its absorption behavior requires further comprehension. This study investigates the impact of silica fume (SF) and metakaolin (MK) on water absorption in UHPC matrix with a high volume of limestone powder (LS) under two curing temperatures, and the variation in water transport with pore size obtained by low field nuclear magnetic resonance (LF-NMR). Relations between cumulative water absorption with other properties were discussed, and the pore size distribution (PSD) measured by Mercury intrusion porosimetry (MIP) was compared with that determined by LF-NMR. Results showed that MK outperformed SF in reducing water absorption in UHPC matrix, containing 30% LS under steam curing due to the synergistic effect between MK and LS. The incorporation of LS greatly affected the water absorption process of UHPC matrix. In samples without LS, capillary and gel pores absorbed water rapidly within the first 6 h and slowly from 6 h to 48 h simultaneously. However, in samples with 30% LS, gel pore water decreased during water absorption process due to the coarsening of gel pores. MK was able to suppress gel pore deterioration caused by the addition of a large amount of LS. Compared with PSD measured by MIP, NMR performed better in detecting micropores (<10 nm).
Effect of Different Ameliorants on the Infiltration and Decontamination Capacities of Soil
Authors: Sang Tianyi , Kang Aihong , Zhang Yao , Li Bo , Mao Huiwen , Kong Heyu
Published: March 2023

The expansion of urban construction areas can reduce the infiltration rate of rainwater in permeable land, and a large amount of runoff rainwater cannot penetrate the soil. In extreme rainstorm weather, it is easy to cause serious urban waterlogging problems. To improve the infiltration and decontamination ability of green space soil, two types of inorganic ameliorants (i.e., sand and grain shell) and structural ameliorants (i.e., desulfurization gypsum and polyacrylamide) were utilized as amendments in the soil. The influence of the selected ameliorants on the infiltration and decontamination ability was analyzed through a soil infiltration test, soil pore distribution determination and a soil decontamination test. Three parameters including the soil infiltration rate, pore distribution characteristics and pollutant removal rate were proposed. The results showed that sand, grain shells and desulfurization gypsum (FGD gypsum) all enhanced the infiltration capacity of soil, while PAM decreased the infiltration capacity. Meanwhile, mixed sand and grain shell with the FGD gypsum and polyacrylamide can effectively improve the decontamination capacity of the soil. Comprehensive analysis showed that the better improvement combination is 10% sand + 20% grain hull + 0.5 g/kg FGD gypsum + 0.1 g/kg PAM.
Debonding Detection in Aluminum/Rigid Polyurethane Foam Composite Plates Using A0 Mode LAMB Wave EMATs
Authors: Yang Xin , Xu Jiang , Zhang Shuchang , Tu Jun
Published: March 2023

Aluminum/rigid polyurethane foam composite plates (ARCPs) are widely used for thermal insulation. The interface debonding generated during manufacturing degrades the thermal insulation performance of an ARCP. In this study, the debonding of an ARCP, a composite plate with a porous and damped layer of rigid polyurethane foam (RPUF), was detected using A0 mode Lamb wave electromagnetic acoustic transducers (EMATs). The low energy transmission coefficient at the interface caused by the large acoustic impedance difference between aluminum and RPUF made the detection difficult. Based on these structural characteristics, an A0 mode Lamb wave with large out-of-plane displacement was used to detect the debonding. EMATs are preferred for generating A0 mode Lamb waves due to their advantages of being noncontact, not requiring a coupling agent, and providing convenient detection. A finite element simulation model considering the damping of the RPUF layer, the damping of the PU film at the interface, and the bonding stiffness of the interface was established. The simulation results indicated that the Lamb wave energy in the aluminum plate transmits into the RPUF layer in small amounts. However, the transmitted energy rapidly attenuated and was not reflected into the aluminum plate, as the RPUF layer was thick and highly damped. Therefore, energy attenuation was evident and could be used to characterize the debonding. An approximately linear relationship between the amplitude of the received signals and the debonding length was obtained. Experiments were performed on an ARCP using EMATs, and the experimental results were in good agreement with the simulation results.
A Multilevel Physically Based Model of Recrystallization: Analysis of the Influence of Subgrain Coalescence at Grain Boundaries on the Formation of Recrystallization Nuclei in Metals
Authors: Trusov Peter , Kondratev Nikita , Baldin Matvej , Bezverkhy Dmitry
Published: March 2023

This paper considers the influence of subgrain coalescence at initial high-angle boundaries on the initiation and growth of recrystallization nuclei (subgrains) under thermomechanical treatment. With certain processing regimes, adjacent subgrains in polycrystalline materials can be assembled into clusters during coalescence. Subgrain clusters at high-angle boundaries are the preferred potential nuclei of recrystallization. Coalescence is one of the dynamic recovery mechanisms, a competing process to recrystallization. When intensive coalescence develops on both sides of the grain boundary, recrystallization slows down or even stops. The problem formulated is solved using a multilevel modeling apparatus with internal variables. Application of the statistical multilevel model modified to take into account the local interaction between crystallites makes it possible to explicitly describe dynamic recrystallization and recovery. The results of modeling the behavior of a copper sample are presented and the effects of temperature, deformation velocity and subgrain structure on the formation and growth of recrystallization nuclei at arbitrary and special grain boundaries during coalescence are analyzed.
In Situ Electrochemical Monitoring of the Crevice Corrosion Process of the 7075-T651 Aluminium Alloy in Acidic NaCl and NaNO3 Solution
Authors: Wang Shengjie , Cao Yamin , Liu Xiaohang , Cai Guangyi
Published: March 2023

The crevice corrosion of the 7075-T651 aluminium alloy was investigated using in situ electrochemical impedance spectroscopy (EIS), potentiodynamic polarization curves (PC), and H+ sensors in acidic NaCl solution with different contents of NaNO3. In the solution without NaNO3, the pH in the crevice increased rapidly and gradually reached a relatively stable status. The corrosion of the aluminium alloy in the crevice was inhibited and crevice corrosion could not be initiated. In the solution with NaNO3, the pH increased rapidly at the initial immersion period and then decreased gradually. The corrosion of the aluminium alloy inside the crevice could be enhanced and the corrosion of the aluminium alloy outside crevice could be inhibited. This triggered crevice corrosion in the solution with NaNO3. The inhibited corrosion outside the crevice can be attributed to the improved passive film of the specimen outside the crevice by nitrate. The accumulated secondary products of ammonia inside the crevice led to selective dissolution of copper, which triggered the nucleation of pitting corrosion and promoted the corrosion of the specimen inside the crevice.
On the Critical Condition for Flame Acceleration in Hydrogen-Based Mixtures
Authors: Kiverin Alexey , Tyurnin Alexey , Yakovenko Ivan
Published: March 2023

The paper presents a novel numerical approach to the quantitative estimation of the concentration limits for flame acceleration in hydrogen-based mixtures. A series of calculations are carried out for hydrogen–air and hydrogen–oxygen flames in channels. The analysis of the obtained numerical results provided the value of 11 ± 0.25 % hydrogen content in the mixture as a lean concentration limit of flame acceleration that agrees well with the available experimental data. Moreover, the basic physical mechanism responsible for the transition from the steady mode of flame propagation to the accelerated one is distinguished. The mechanism is related to flame stretching in the region of interaction with the boundary layer and the competition between the joint increase in burning rate and heat losses. The novel technique for the estimation of concentration limits of flame acceleration presented here can be applied to assess combustion conditions inside combustors of energy and propulsion systems fed with hydrogen. The results are also useful in estimating explosion and fire risks in hydrogen storage, transport, and utilization facilities as parts of hydrogen energy and propulsion systems.
Government Subsidy Strategies Considering Greenness on Agricultural Product E-Commerce Supply Chain
Authors: Guo Fangfang , Zhang Tao , Huang Xiuquan , Zhong Yaoguang
Published: March 2023

Based on the Stackelberg game theory, this paper explores the incentive effects of five government subsidy strategies on agricultural products in e-commerce. A two-tier e-commerce supply chain of one farmer and one e-commerce platform is constructed to examine the impact of five different government subsidy strategies on the greenness of an agricultural product, the wholesale price, the selling price, and the profit of the supply chain. The results show that the effect of offering government subsidies is significant. Also, the direct subsidization from the government to a farmer has the maximum effect on the sales and greenness of the agricultural product. The results of this study provide policy implications for governments in establishing a sustainable mechanism through direct subsidization.
Approximate Controllability of Neutral Functional Integro-Differential Equations with State-Dependent Delay and Non-Instantaneous Impulses
Authors: Bensalem Abdelhamid , Salim Abdelkrim , Benchohra Mouffak , Fečkan Michal
Published: March 2023

In this manuscript, we investigate the issue of approximate controllability for a certain class of abstract neutral integro-differential equations having non-instantaneous impulsions and being subject to state-dependent delay. Our methodology relies on the utilization of resolvent operators in conjunction with Darbo’s fixed point theorem. To exemplify the practical implications of our findings, we provide an illustration.
Significance of Weissenberg Number, Soret Effect and Multiple Slips on the Dynamic of Biconvective Magnetohydrodynamic Carreau Nanofuid Flow
Authors: Kumar Pardeep , Poonia Hemant , Ali Liaqat , Shah Nehad Ali , Chung Jae Dong
Published: March 2023

This study focused on the analysis of two-dimensional incompressible magnetohydrodynamic Carreau nanofluid flow across a stretching cylinder containing microorganisms with the impacts of chemical reactions and multiple slip boundary conditions. Moreover, the main objective is concerned with the enhancement of thermal transportation with the effect of heat source and bioconvection. By assigning pertinent similarity transitions to the governing partial differential equations, a series of equations (ODES) is generated. An optimum computational solver, namely the bvp5c software package, is utilized for numerical estimations. The impact of distinct parameters on thermal expansion, thermophoresis, and the Nusselt number has been emphasized, employing tables, diagrams, and surface maps for both shear thinning (n < 1) and shear thickening (n > 1) instances. Motile concentration profiles decrease with Lb and the motile microorganism density slip parameter. It is observed that with increasing values of Pr, both the boundary layer thickness and temperature declined in both cases. The Weissenberg number demonstrates a different nature depending on the type of fluid; skin friction, the velocity profile and Nusselt number drop when n < 1 and increase when n > 1. The two- and three-dimensional graphs show the simultaneous effect of involving parameters with physical quantities. The accuracy of the existing observations is evidenced by the impressive resemblance between the contemporary and preceding remedies.
Echinochrome A Prevents Diabetic Nephropathy by Inhibiting the PKC-Iota Pathway and Enhancing Renal Mitochondrial Function in db/db Mice
Authors: Pham Trong , Nguyen To , Yun Hyeong , Vasileva Elena , Mishchenko Natalia , Fedoreyev Sergey , Stonik Valentin , Vu Thu , Nguyen Huy , Cho Sung , Kim Hyoung , Han Jin
Published: March 2023

Echinochrome A (EchA) is a natural bioproduct extracted from sea urchins, and is an active component of the clinical drug, Histochrome®. EchA has antioxidant, anti-inflammatory, and antimicrobial effects. However, its effects on diabetic nephropathy (DN) remain poorly understood. In the present study, seven-week-old diabetic and obese db/db mice were injected with Histochrome (0.3 mL/kg/day; EchA equivalent of 3 mg/kg/day) intraperitoneally for 12 weeks, while db/db control mice and wild-type (WT) mice received an equal amount of sterile 0.9% saline. EchA improved glucose tolerance and reduced blood urea nitrogen (BUN) and serum creatinine levels but did not affect body weight. In addition, EchA decreased renal malondialdehyde (MDA) and lipid hydroperoxide levels, and increased ATP production. Histologically, EchA treatment ameliorated renal fibrosis. Mechanistically, EchA suppressed oxidative stress and fibrosis by inhibiting protein kinase C-iota (PKCι)/p38 mitogen-activated protein kinase (MAPK), downregulating p53 and c-Jun phosphorylation, attenuating NADPH oxidase 4 (NOX4), and transforming growth factor-beta 1 (TGFβ1) signaling. Moreover, EchA enhanced AMPK phosphorylation and nuclear factor erythroid-2-related factor 2 (NRF2)/heme oxygenase 1 (HO-1) signaling, improving mitochondrial function and antioxidant activity. Collectively, these findings demonstrate that EchA prevents DN by inhibiting PKCι/p38 MAPK and upregulating the AMPKα/NRF2/HO-1 signaling pathways in db/db mice, and may provide a therapeutic option for DN.
Application of Optical Coherence Tomography (OCT) to Analyze Membrane Fouling under Intermittent Operation
Authors: Lee Song , Cho Hyeongrak , Choi Yongjun , Lee Sangho
Published: March 2023

There is increasing interest in membrane systems powered by renewable energy sources, including solar and wind, that are suitable for decentralized water supply in islands and remote regions. These membrane systems are often operated intermittently with extended shutdown periods to minimize the capacity of the energy storage devices. However, relatively little information is available on the effect of intermittent operation on membrane fouling. In this work, the fouling of pressurized membranes under intermittent operation was investigated using an approach based on optical coherence tomography (OCT), which allows non-destructive and non-invasive examination of membrane fouling. In reverse osmosis (RO), intermittently operated membranes were investigated by OCT-based characterization. Several model foulants such as NaCl and humic acids were used, as well as real seawater. The cross-sectional OCT images of the fouling were visualized as a three-dimensional volume using Image J. The OCT images were used to quantitatively measure the thickness of foulants on the membrane surfaces under different operating conditions. The results showed that intermittent operation retarded the flux decrease due to fouling compared to continuous operation. The OCT analysis showed that the foulant thickness was significantly reduced by the intermittent operation. The decrease in foulant layer thickness was found to occur when the RO process was restarted in intermittent operation.
Tuning PVDF Membrane Porosity and Wettability Resistance via Varying Substrate Morphology for the Desalination of Highly Saline Water
Authors: Baroud Turki N.
Published: March 2023

Here, we report the fabrication of a series of highly efficient polyvinylidene fluoride (PVDF) membranes via substrate morphology variations. A wide range of sandpaper grit sizes (150–1200) were utilized as casting substrates. The effect of the penetration of abrasive particles present on the sandpapers on the casted polymer solution was tuned, and the impact of these particles on porosity, surface wettability, liquid entry pressure and morphology were investigated. The membrane distillation performance of the developed membrane on sandpapers was evaluated for the desalination of highly saline water (70,000 ppm). Interestingly, the utilization of cheap and widely available sandpapers as a substrate for casting can not only help in tuning the MD performance, but also in producing highly efficient membranes with stable salt rejection (up to 100%) and a 210% increase in the permeate flux over 24 h. The findings in this study will help in delineating the role of substrate nature in controlling the produced membrane characteristics and performance.
Wear Behavior Phenomena of TiN/TiAlN HiPIMS PVD-Coated Tools on Milling Inconel 718
Authors: Sousa Vitor F. C. , Fernandes Filipe , Silva Francisco J. G. , Costa Rúben D. F. S. , Sebbe Naiara , Sales-Contini Rita C. M.
Published: March 2023

Due to Inconel 718’s high mechanical properties, even at higher temperatures, tendency to work-harden, and low thermal conductivity, this alloy is considered hard to machine. The machining of this alloy causes high amounts of tool wear, leading to its premature failure. There seems to be a gap in the literature, particularly regarding milling and finishing operations applied to Inconel 718 parts. In the present study, the wear behavior of multilayered PVD HiPIMS (High-power impulse magnetron sputtering)-coated TiN/TiAlN end-mills used for finishing operations on Inconel 718 is evaluated, aiming to establish/expand the understanding of the wear behavior of coated tools when machining these alloys. Different machining parameters, such as cutting speed, cutting length, and feed per tooth, are tested, evaluating the influence of these parameters’ variations on tool wear. The sustained wear was evaluated using SEM (Scanning electron microscope) analysis, characterizing the tools’ wear and identifying the predominant wear mechanisms. The machined surface was also evaluated after each machining test, establishing a relationship between the tools’ wear and production quality. It was noticed that the feed rate parameter exerted the most influence on the tools’ production quality, while the cutting speed mostly impacted the tools’ wear. The main wear mechanisms identified were abrasion, material adhesion, cratering, and adhesive wear. The findings of this study might prove useful for future research conducted on this topic, either optimization studies or studies on the simulation of the milling of Inconel alloys, such as the one presented here.
Association of Metabolomic Biomarkers with Sleeve Gastrectomy Weight Loss Outcomes
Authors: Miller Wendy M. , Ziegler Kathryn M. , Yilmaz Ali , Saiyed Nazia , Ustun Ilyas , Akyol Sumeyya , Idler Jay , Sims Matthew D. , Maddens Michael E. , Graham Stewart F.
Published: March 2023

This prospective observational study aimed to evaluate the association of metabolomic alterations with weight loss outcomes following sleeve gastrectomy (SG). We evaluated the metabolomic profile of serum and feces prior to SG and three months post-SG, along with weight loss outcomes in 45 adults with obesity. The percent total weight loss for the highest versus the lowest weight loss tertiles (T3 vs. T1) was 17.0 ± 1.3% and 11.1 ± 0.8%, p < 0.001. Serum metabolite alterations specific to T3 at three months included a decrease in methionine sulfoxide concentration as well as alterations to tryptophan and methionine metabolism (p < 0.03). Fecal metabolite changes specific to T3 included a decrease in taurine concentration and perturbations to arachidonic acid metabolism, and taurine and hypotaurine metabolism (p < 0.002). Preoperative metabolites were found to be highly predictive of weight loss outcomes in machine learning algorithms, with an average area under the curve of 94.6% for serum and 93.4% for feces. This comprehensive metabolomics analysis of weight loss outcome differences post-SG highlights specific metabolic alterations as well as machine learning algorithms predictive of weight loss. These findings could contribute to the development of novel therapeutic targets to enhance weight loss outcomes after SG.
Low-Viscosity Polydimethylsiloxane Resin for Facile 3D Printing of Elastomeric Microfluidics
Authors: Fleck Elyse , Keck Charlise , Ryszka Karolina , DeNatale Emma , Potkay Joseph
Published: March 2023

Microfluidics is a rapidly advancing technology with expansive applications but has been restricted by slow, laborious fabrication techniques for polydimethylsiloxane (PDMS)-based devices. Currently, 3D printing promises to address this challenge with high-resolution commercial systems but is limited by a lack of material advances in generating high-fidelity parts with micron-scale features. To overcome this limitation, a low-viscosity, photopolymerizable PDMS resin was formulated with a methacrylate-PDMS copolymer, methacrylate-PDMS telechelic polymer, photoabsorber, Sudan I, photosensitizer, 2-isopropylthioxanthone, and a photoinitiator, 2,4,6-trimethyl benzoyl diphenylphosphine oxide. The performance of this resin was validated on a digital light processing (DLP) 3D printer, an Asiga MAX X27 UV. Resin resolution, part fidelity, mechanical properties, gas permeability, optical transparency, and biocompatibility were investigated. This resin produced resolved, unobstructed channels as small as 38.4 (±5.0) µm tall and membranes as thin as 30.9 (±0.5) µm. The printed material had an elongation at break of 58.6% ± 18.8%, Young’s modulus of 0.30 ± 0.04 MPa, and was highly permeable to O2 (596 Barrers) and CO2 (3071 Barrers). Following the ethanol extraction of the unreacted components, this material demonstrated optical clarity and transparency (>80% transmission) and viability as a substrate for in vitro tissue culture. This paper presents a high-resolution, PDMS 3D-printing resin for the facile fabrication of microfluidic and biomedical devices.
Microwave Passive Direction-Finding Method Based on NV Color Center in Diamond
Authors: Wang Qi , Liu Yusong , Qin Yue , Guo Hao , Tang Jun
Published: March 2023

In this study, we established a passive direction-finding scheme based on microwave power measurement: Microwave intensity was detected using microwave-frequency proportion integration differentiation control and coherent population oscillation effect converting the change in microwave resonance peak intensity into a shift of the microwave frequency spectrum, for which the minimum microwave intensity resolution was −20 dBm. The direction angle of the microwave source was calculated using the weighted global least squares method of microwave field distribution. This lay in the 12~26 dBm microwave emission intensity range, and the measurement position was in the range of (−15°~15°). The average angle error of the angle measurement was 0.24°, and the maximum angle error was 0.48°. In this study, we established a microwave passive direction-finding scheme based on quantum precision sensing, which measures the microwave frequency, intensity, and angle in a small space and has a simple system structure, small equipment size, and low system power consumption. In this study, we provide a basis for the future application of quantum sensors in microwave direction measurements.
Measuring the Flex Life of Conductive Yarns in Narrow Fabric
Authors: Veske Paula , Bossuyt Frederick , Thielemans Filip , Vanfleteren Jan
Published: March 2023

Due to constant advancements in materials research, conductive textile-based materials have been used increasingly in textile-based wearables. However, due to the rigidity of electronics or the need for their encapsulation, conductive textile materials, such as conductive yarns, tend to break faster around transition areas than other parts of e-textile systems. Thus, the current work aims to find the limits of two conductive yarns woven into a narrow fabric at the electronics encapsulation transition point. The tests consisted of repeated bending and mechanical stress, and were conducted using a testing machine built from off-the-shelf components. The electronics were encapsulated with an injection-moulded potting compound. In addition to identifying the most reliable conductive yarn and soft–rigid transition materials, the results examined the failure process during the bending tests, including continuous electrical measurements.
Adaptive Dynamic Analysis of MEMS Gyroscope Random Noise Based on PID-DAVAR
Authors: Zhang Jianing , Li Pinghua , Yu Zhiyu , Liu Jinghao , Zhang Xiaoyang , Zhuang Xuye
Published: March 2023

As a MEMS gyroscope is susceptible to environmental interference, its performance is degraded due to random noise. Accurate and rapid analysis of random noise of MEMS gyroscope is of great significance to improve the gyroscope’s performance. A PID-DAVAR adaptive algorithm is designed by combining the PID principle with DAVAR. It can adaptively adjust the length of the truncation window according to the dynamic characteristics of the gyroscope’s output signal. When the output signal fluctuates drastically, the length of the truncation window becomes smaller, and the mutation characteristics of the intercepted signal are analyzed detailed and thoroughly. When the output signal fluctuates steadily, the length of the truncation window becomes larger, and the intercepted signals are analyzed swiftly and roughly. The variable length of the truncation window ensures the confidence of the variance and shortens the data processing time without losing the signal characteristics. Experimental and simulation results show that the PID-DAVAR adaptive algorithm can shorten the data processing time by 50%. The tracking error of the noise coefficients of angular random walk, bias instability, and rate random walk is about 10% on average, and the minimum error is about 4%. It can accurately and promptly present the dynamic characteristics of the MEMS gyroscope’s random noise. The PID-DAVAR adaptive algorithm not only satisfies the requirement of variance confidence but also has a good signal-tracking ability.
Investigating the Performance of the Multi-Lobed Leaf-Shaped Oscillatory Obstacles in Micromixers Using Bulk Acoustic Waves (BAW): Mixing and Chemical Reaction
Authors: Kordzadeh-Kermani Vahid , Dartoomi Hossein , Azizi Mina , Ashrafizadeh Seyed Nezameddin , Madadelahi Masoud
Published: March 2023

Proper mixing in microfluidic devices has been a concern since the early development stages. Acoustic micromixers (active micromixers) attract significant attention due to their high efficiency and ease of implementation. Finding the optimal geometries, structures, and characteristics of acoustic micromixers is still a challenging issue. In this study, we considered leaf-shaped obstacle(s) having a multi-lobed structure as the oscillatory part(s) of acoustic micromixers in a Y-junction microchannel. Four different types of leaf-shaped oscillatory obstacles, including 1, 2, 3, and 4-lobed structures, were defined, and their mixing performance for two fluid streams was evaluated numerically. The geometrical parameters of the leaf-shaped obstacle(s), including the number of lobes, lobes’ length, lobes’ inside angle, and lobes’ pitch angle, were analyzed, and their optimum operational values were discovered. Additionally, the effects of the placement of oscillatory obstacles in three configurations, i.e., at the junction center, on the side walls, and both, on the mixing performance were evaluated. It was found that by increasing the number and length of lobes, the mixing efficiency improved. Furthermore, the effect of the operational parameters, such as inlet velocity, frequency, and intensity of acoustic waves, was examined on mixing efficiency. Meanwhile, the occurrence of a bimolecular reaction in the microchannel was analyzed at different reaction rates. It was proven that the reaction rate has a prominent effect at higher inlet velocities.
Development of a Multicomponent Microbiological Soil Inoculant and Its Performance in Sweet Potato Cultivation
Authors: Nagy Viktor Dávid , Zhumakayev Anuar , Vörös Mónika , Bordé Ádám , Szarvas Adrienn , Szűcs Attila , Kocsubé Sándor , Jakab Péter , Monostori Tamás , Škrbić Biljana D. , Mohai Edina , Hatvani Lóránt , Vágvölgyi Csaba , Kredics László
Published: March 2023

The cultivation and consumption of sweet potato (Ipomoea batatas) are increasing globally. As the usage of chemical fertilizers and pest control agents during its cultivation may lead to soil, water and air pollution, there is an emerging need for environment-friendly, biological solutions enabling increased amounts of healthy crop and efficient disease management. Microbiological agents for agricultural purposes gained increasing importance in the past few decades. Our goal was to develop an agricultural soil inoculant from multiple microorganisms and test its application potential in sweet potato cultivation. Two Trichoderma strains were selected: Trichoderma ghanense strain SZMC 25217 based on its extracellular enzyme activities for the biodegradation of plant residues, and Trichoderma afroharzianum strain SZMC 25231 for biocontrol purposes against fungal plant pathogens. The Bacillus velezensis strain SZMC 24986 proved to be the best growth inhibitor of most of the nine tested strains of fungal species known as plant pathogens, therefore it was also selected for biocontrol purposes against fungal plant pathogens. Arthrobacter globiformis strain SZMC 25081, showing the fastest growth on nitrogen-free medium, was selected as a component with possible nitrogen-fixing potential. A Pseudomonas resinovorans strain, SZMC 25872, was selected for its ability to produce indole-3-acetic acid, which is among the important traits of potential plant growth-promoting rhizobacteria (PGPR). A series of experiments were performed to test the selected strains for their tolerance to abiotic stress factors such as pH, temperature, water activity and fungicides, influencing the survivability in agricultural environments. The selected strains were used to treat sweet potato in two separate field experiments. Yield increase was observed for the plants treated with the selected microbial consortium (synthetic community) in comparison with the control group in both cases. Our results suggest that the developed microbial inoculant has the potential to be used in sweet potato plantations. To the best of our knowledge, this is the first report about the successful application of a fungal-bacterial consortium in sweet potato cultivation.
Sedimentology and Paleodepositional Environment of the Early-Middle Miocene Tanjong Formation, Southeast Sabah: Evidence from Bulk Geochemistry and Palynology Analyses
Authors: Hisham Nur Faiqah , Zainal Abidin Nor Syazwani
Published: March 2023

Eight stratigraphic sections from well-exposed outcrops of the Early to Middle Miocene Tanjong Formation in the Kalabakan area, southeast Sabah, were investigated using an integrated approach, in which a comprehensive sedimentological facies analysis was linked with bulk geochemistry and palynological analyses. The integration of facies analysis, elemental CHNS, Fourier-transform infrared spectroscopy (FTIR), and palynological data provided a refined evaluation of the origin of organic matter (OM) and the reconstruction of the paleodepositional model. Seven facies associations were classified in the studied Tanjong Formation from 12 lithofacies components, interpreted as environments ranging from fluvial-deltaic to shallow marine: FA1—Floodplain, FA2—Fluvial channel, FA3—Coastal peat mires, FA4—Tidal flat, FA5—Delta front, FA6—Mouth bar, and FA7—Upper shoreface. Evaluation of the C/N ratio ranged between 4 and 48, and the total sulfur content ranged from 0.5 to 3. Elemental CHNS analysis suggests that the organic matter extracted from the coal and mudstone originated from terrestrial plants and fresh marine plankton. Accordingly, the three most prevalent FTIR spectra from the coal and mudstone samples were the OH- functional group stretching, the absorption spectrum of aromatic C=C stretching, and aromatic in-plane/out-of-plane C-H bending. Terrestrially derived organic matter within the examined samples was further validated by the predominance of aromatic compounds, and the palynological analysis indicated a back-mangrove freshwater pollen assemblage and a lower coastal plain setting proximal to the marine environment. The integrated findings from this research are vital in reconstructing a paleodepositional environment model that will improve the predictability of the petroleum system mechanisms and the future hydrocarbon potential for conventional petroleum exploration.
Formation of High-Silica Leucocratic Granitoids on the Late Devonian Peraluminous Series of the Russian Altai: Mineralogical, Geochemical, and Isotope Reconstructions
Authors: Kruk Nikolay N. , Gavryushkina Olga A. , Smirnov Sergey Z. , Kruk Elena A. , Rudnev Sergey N. , Semenova Dina V.
Published: March 2023

This paper presents data on the geological position, geochemical features, main mineral composition (micas, feldspars), and melt and fluid inclusions in quartz from Aba high-silica leucocratic granitoids in the western part of the Talitsa batholith, Russian Altai. According to these new geochemical data, the granitoids are classified as S-type, meaning they are formed via the partial melting of metasedimentary source rocks. Geological data and oxygen isotope composition analysis indicate that major-phase granitoid magma evolution took place at the level of intrusion formation, whereas the parent melt of late-phase leucogranite evolved in a deeper chamber. The geochemical features (HFSE and REE, and REE spectra) of the granitoids indicate significantly higher differentiation in the late leucocratic phase. The presence of coexisting syngenetic melt and fluid inclusions shows that leucogranite magma was already saturated with volatiles in the early crystallization stages. Based on the new data presented in this work, the Aba rock formation is associated with the volatile saturation of magmatic melts, the exsolution of a fluid phase, and magma degassing.