bluuebunny/crossref_metadata_2025 huggingface dataset:
Insights into the Effects of Study Area Size and Soil Sampling Density in the Prediction of Soil Organic Carbon by Vis-NIR Diffuse Reflectance Spectroscopy in Two Forest Areas
Authors: Conforti Massimo , Buttafuoco Gabriele
Published: December 2022

Sustainable forest land management requires measuring and monitoring soil organic carbon. Visible and near-infrared diffuse reflectance spectroscopy (Vis-NIR, 350–2500 nm), although it has become an important method for predicting soil organic carbon (SOC), requires further studies and methods of analysis to realize its full potential. This study aimed to determine if the size of the study area and soil sampling density may affect the performance of Vis-NIR diffuse reflectance spectroscopy in the prediction of soil organic carbon. Two forest sites in the Calabria region (southern Italy), which differ in terms of area and soil sampling density, were used. The first one was Bonis catchment area (139 ha) with a cover consisting mainly of Calabrian pine, while the second was Mongiana forest area (33.2 ha) within the “Marchesale” Biogenetic Nature Reserve, which is covered by beech. The two study areas are relatively homogeneous regarding parent material and soil type, while they have very different soil sampling density. In particular, Bonis catchment has a lower sampling density (135 samples out of 139 ha) than Mongiana area (231 samples out of 33.2 ha). Three multivariate calibration methods (principal component regression (PCR), partial least square regression (PLSR), and support vector machine regression (SVMR)) were combined with different pretreatment techniques of diffuse reflectance spectra (absorbance, ABS, standard normal variate, SNV, and Savitzky–Golay filtering with first derivative (SG 1st D). All soil samples (0–20 cm) were analyzed in the laboratory for SOC concentration and for measurements of diffuse reflectance spectra in the Vis-NIR region. The set of samples from each study area was randomly divided into a calibration set (70%) and a validation set (30%). The assessment of the goodness for the different calibration models and the following SOC predictions using the validation sets was based on three parameters: the coefficient of determination (R2), the root mean square error (RMSE), and the interquartile range (RPIQ). The results showed that for the two study areas, different levels of goodness of the prediction models depended both on the type of pretreatment and the multivariate method used. Overall, the prediction models obtained with PLSR and SVMR performed better than those of PCR. The best performance was obtained with the SVMR method combined with ABS + SNV + SG 1st D pretreatment (R2 ≥ 0.77 and RPIQ > 2.30). However, there is no result that can absolutely provide definitive indications of either the effects of the study area size and soil sampling density in the prediction of SOC by vis-NIR spectroscopy, but this study fostered the need for future investigations in areas and datasets of different sizes from those in this study and including also different soil landscapes.
Dynamics of Urban Land per Capita in China from 2000 to 2016
Authors: Li Yiyu , Huang Qingxu , Zhang Ling , Li Jian , Sui Yingfei , Zhang Weichen
Published: December 2022

As a proxy for human activity, per capita urban land has great significance for urban planning. We still lack a comprehensive understanding of per capita urban land from the perspective of urban–rural gradients. Thus, based on the concentric buffering method and the dynamic-time-warp clustering method, this research analyzes the urban–rural gradient of the per capita urban land of 345 cities in China in 2000, 2010, and 2016. We find that the per capita urban land in China grew from 110.2 m2/person in 2000 to 118.9 m2/person, increasing by 7.9%. The urban–rural gradient of the per capita urban land can be classified into six types: (1) large city with a mono peak; (2) large city with a fluctuating increase; (3) medium city with a mono peak; (4) medium city with a declining trend; (5) small city with a mono peak, and (6) small city with a declining trend. In addition, most cities shifted from a mono-peak type to a declining type, which suggested that the low-density, sprawling development was intensifying. The dynamic-time-warp clustering method used in this research can effectively compare trends of the urban–rural gradient of per capita urban land across cities, which can be applied to the analysis of the urban–rural gradient of air pollution, urban green space, and urban heat islands.
Challenges Entailed in Applying Ecosystem Services Supply and Demand Mapping Approaches: A Practice Report
Authors: Dworczyk Claudia , Burkhard Benjamin
Published: December 2022

The Ecosystem Services (ES) concept has been acknowledged by scientists, policy-makers and practitioners to have the potential to support sustainable policy- and land-use decision-making. Therefore, a growing number of research activities are investigating the integration potential of the ES concept into real-world policy- and decision-making processes. These research activities are often confronted with conceptual challenges and methodological obstacles when applying different ES mapping approaches. This study is reporting those challenges encountered during a research project in Germany. In this research project, two urban regions, Rostock and Munich, were selected as case-study areas. In both urban regions, dynamic urbanisation processes occur across the urban administrative boundaries and threaten the supply of multiple ES in the periurban landscapes. The research project invited local stakeholders from the two urban regions to workshops and online meetings to discuss ES-related topics. For those events, maps visualising the spatial patterns of multiple ES were needed for communication and awareness-raising of the ES concept. We chose commonly used and relatively easy-to-apply mapping methods such as: (1) expert-based ES matrix approach, (2) simple GIS mapping with proxy indicators and data, and (3) simple ES models such as InVEST. We encountered several challenges during the mapping processes: The expert-based matrix approach provided valuable results for ES supply, but had limitations in assessing expert estimates for ES demand. Alongside other factors, evolving barriers related to the conceptual complexity of ES demand. Data unavailability/inaccessibility resulted in difficulties mapping all selected ES with proxy indicators at the targeted regional scale. So far, only a few individual ES can be modelled with InVEST models. Despite these challenges, the resulting maps were helpful for communication with local stakeholders. The discussions with stakeholders provided valuable insights into the future needs for ES research and identified existing barriers and challenges. We want to summarise and share our experiences and provide recommendations for future research on mapping ES supply and demand in urban regions.
Seasonal Trap Abundance of Two Species of Psilochalcis Kieffer (Hymenoptera: Chalcididae) in Rangelands of the Eastern Great Basin of Utah, USA
Authors: Petersen Mark J. , Anderson Val J. , Johnson Robert L. , Eggett Dennis L.
Published: December 2022

Two species of Psilochalcis (Hymenoptera: Chalcididae) wasps occurring in the Great Basin region of the western United States were sampled from three locations in central Utah (USA) over a two-year period using Malaise traps. Each location is composed of four contiguous habitat types: pinyon/juniper (Pinus edulis or P. monophylla and Juniperus osteosperma), sagebrush (Artemisia tridentata), cheatgrass (Bromus tectorum), and crested wheatgrass (Agropyron cristatum). Seasonal trap abundance for each Psilochalcis species was determined. Psilochalcis minuta Petersen and Psilochalcis quadratis Petersen occur in highest abundance from mid-May to early August. Psilochalcis minuta demonstrates a significant association with pinyon/juniper habitat, specifically at the Utah; Juab County, Yuba Valley sample site, whereas P. quadratis demonstrates a significant association with cheatgrass (Bromus tectorum) habitat at the same location.
Evaluation of the Gross Ecosystem Product and Analysis of the Transformation Path of “Two Mountains” in Hulunbuir City, China
Authors: Zhao Na , Wang Hui , Zhong Jingqiu , Bai Yun , Yi Sang
Published: December 2022

The objective assessment of ecological systems forms the basis of solving ecological environmental problems. Evaluating the ecosystem status of each county through the gross ecosystem product (GEP) can reveal the value of each ecosystem. In this study, we used the eco-economic method to calculate the GEP and the green gold index (GGI) of 13 counties in Hulunbuir City between 2015 and 2020. The results show that: (1) The GEP of Hulunbuir City in 2020 was 980.025 billion yuan. The GGI was 8.36, which was much higher than the national average. (2) Forestry and pastoral regions were the main contributors to the regulation service. (3) Hulunbuir City had the largest forest value, while the farmland value was the lowest. The most important sources of forest, grassland, wetland, water, and farmland value were Oroqen, Xin Right Banner, Xin Left Banner, Xin Right Banner, and Morin Banner, respectively. Based on our analysis, we found significant results through the transformation of the “Two Mountains” in Erguna, Genhe, and Zhalantun. The other counties in our study must optimize ecological research with respect to the traditional economic model. Our results provide a scientific reference for the application of the “Two Mountains” base in each county.
Assessing Net Environmental and Economic Impacts of Urban Forests: An Online Decision Support Tool
Authors: Babí Almenar Javier , Petucco Claudio , Navarrete Gutiérrez Tomás , Chion Laurent , Rugani Benedetto
Published: December 2022

Nature-based solutions (NBS) are becoming popular in urban planning and policy making as cost-effective solutions capable of delivering multiple ecosystem services and addressing several societal challenges. So far, however, the cost-effectiveness of urban NBS projects has not been consistently quantified by built environment professionals, who lack user-friendly tools to account for the environmental costs and benefits of NBS. This paper presents a prototype online decision support tool (NBenefit$®) that calculates the negative and positive environmental impacts, externalities, and financial values of planned urban forests over their entire life cycle. NBenefit$ relies on a modelling framework that combines system dynamics, urban ecology, and life cycle thinking approaches, and it is presented as a visual web-based interface. An online map and a grid of cells is used to map the site of intervention, to delineate the size of the urban forest, and to define variations in abiotic, biotic, and management attributes in each site. Outputs are provided by year, for the entire site and NBS life cycle. The potential value of NBenefit$ as a supporting tool was exemplified with the calculation of 48 urban forest archetypes, a few of which were used to set scenarios for a hypothetical urban forest in Madrid (Spain). The results showcase the impact that decisions taken during the planning, design, or management of an NBS project may have on its long-term performance. Future works will expand the scope of NBenefit$, including other types of urban NBS.
Land Use and Landscape Characteristics Are Associated with Core Forest Patches in Ghana
Authors: Oduro Appiah Joseph , Adei Dina , Agyemang-Duah Williams
Published: December 2022

Land uses and terrain characteristics would likely influence the types and spatial arrangements of forest patches, and generally, forest fragmentation. Whereas prior research has focused mainly on direct land use-induced forest fragmentation, this study models the relationship between the spatial distribution of core forest patches, land uses, and terrain variables. Relying on Landsat images from the Atewa Range Forest Reserve (ARFR) in Ghana, we use machine learning geospatial techniques and statistical methods to process satellite images and model the relationship between core forest patches and associated variables. The study finds that a unit reduction in elevation would significantly likely reduce by 0.995 times the possibility of forest patches being core forests, implying that on lower slopes, core forests are less likely to occur. Additionally, we find that a unit increase in slope gradient significantly increases the odds of a forest patch being among the core forest category by 1.35 times. Moreover, our results show that the odds of forest patches being core forests significantly increase by 1.60 and 2.14 times if patches are found beyond 1 km from logging sites and access roads, respectively. This implies that intact forest patches would likely be found on higher slopes, higher elevations, and areas far away from land uses. Based on the results, we suggest that the protection of forest patches should target higher elevations and slopes and most importantly areas far from land uses whereas forest restoration programs should target areas close to land uses and on lower elevations and lower slopes. With this study demonstrating a significant relationship between core forests, land uses and terrain variables, we present important information to land managers for land monitoring and conservation in the ARFR and other tropical forest regions of the world.
Spatial–Temporal Multivariate Correlation Analysis of Ecosystem Services and Ecological Risk in Areas of Overlapped Cropland and Coal Resources in the Eastern Plains, China
Authors: Wang Xueqing , Ding Zhongyi , Zhang Shaoliang , Hou Huping , Chen Zanxu , Wu Qinyu
Published: December 2022

The overlapped areas of cropland and coal resources play a fundamental role in promoting economic and social progress. However, intensive mining operations in high water-level areas have brought significant spatial–temporal heterogeneity and ecological problems. From the dual dimensions of the ecosystem service value (ESV) and ecological risk (ER), it is of great significance to explore the influence characteristics of underground mining on the landscape, such as above-ground cultivated land, which is valuable to achieving regional governance and coordinated development. In this study, taking Peixian as the research area, a multiple-dimensional correlation framework was constructed based on the revised ESV and ER, integrating the grey relational degree, spatial–temporal heterogeneity, disequilibrium, and inconsistency index to explore the ESV and ER assessment and correlation characteristics from 2010 to 2020. The results show that (1) the ESV showed a high agglomerated distribution pattern in the east, with a net decrease of 13.61%. (2) The ER decreased by 78.18 and was concentrated in the western and southern regions, with overall contiguous and local agglomeration characteristics. This indicates that the ecological security of the region has improved. (3) The comprehensive grey correlation between the cultural service value and the ecological risk index was the highest. Furthermore, the spatial–temporal heterogeneity of the ESV and ER weakened, and the disequilibrium rose and then fell, indicating that the ecosystem gradually tended to be stable. The study is crucial for overlapped cropland and coal resource areas to maintain stability and sustainable development. The multivariate correlation framework provides practical value for ecosystem management and risk control.
Neurovascular Interactions in the Development of the Vasculature
Authors: Takara Kazuhiro , Hayashi-Okada Yumiko , Kidoya Hiroyasu
Published: December 2022

Vertebrates have developed a network of blood vessels and nerves throughout the body that enables them to perform complex higher-order functions and maintain homeostasis. The 16th-century anatomical text ‘De humani corporis fabrica’ describes the networks of blood vessels and nerves as having a branching pattern in which they are closely aligned and run parallel one to another. This close interaction between adjacent blood vessels and nerves is essential not only for organogenesis during development and repair at the time of tissue damage but also for homeostasis and functional expression of blood vessels and nerves. Furthermore, it is now evident that disruptions in neurovascular interactions contribute to the progression of various diseases including cancer. Therefore, we highlight recent advances in vascular biology research, with a particular emphasis on neurovascular interactions.
Parkia speciosa Hassk. Empty Pod Extract Prevents Cardiomyocyte Hypertrophy by Inhibiting MAPK and Calcineurin-NFATC3 Signaling Pathways
Authors: Mustafa Nor Hidayah , Jalil Juriyati , Saleh Mohammed S. M. , Zainalabidin Satirah , Asmadi Ahmad Yusof , Kamisah Yusof
Published: December 2022

Cardiac hypertrophy is an early hallmark during the clinical course of heart failure. Therapeutic strategies aiming to alleviate cardiac hypertrophy via the mitogen-activated protein kinase (MAPK)/calcineurin-nuclear factor of activated T-cells (NFAT) signaling pathway may help prevent cardiac dysfunction. Previously, empty pod ethanol crude extract of Parkia speciosa Hassk was shown to demonstrate protective effects against cardiomyocyte hypertrophy. Therefore, the current study aimed to investigate the effects of various fractions of the plant ethanol extract on the MAPK/NFAT signaling pathway in angiotensin II (Ang II)-induced cardiomyocyte hypertrophy. Simultaneous treatment with ethyl acetate (EA) fraction produced the most potent antihypertrophic effect evidenced by the reduced release of B-type natriuretic peptide (BNP). Subsequently, treatment with the EA fraction (6.25, 12.5, and 25 μg/mL) prevented an Ang II-induced increase in cell surface area, hypertrophic factors (atrial natriuretic peptide and BNP), reactive oxygen species, protein content, and NADPH oxidase 4 expression in the cells. Furthermore, EA treatment attenuated the activation of the MAPK pathway and calcineurin-related pathway (GATA-binding protein 4 and NFATC3), which was similar to the effects of valsartan (positive control). Our findings indicate that the EA fraction prevents Ang II-induced cardiac hypertrophy by regulating the MAPK/calcineurin-NFAT signaling pathway.
Bleeding Risk in Patients with Peripheral Arterial Disease
Authors: Visonà Adriana , Zurlo Chiara , Panzavolta Chiara , Gobbo Annachiara , Zalunardo Beniamino
Published: December 2022

Patients with peripheral arterial disease (PAD) are at high risk of major adverse cardiac events (MACE) and major adverse limb events (MALE). Recently, antithrombotic therapies employing antiplatelet and anticoagulant drugs have proven to be valid in reducing MACE in patients with PAD and polyvascular disease and MALE, particularly in patients who have already been revascularized and remain at increased risk of MALE. However, more aggressive antithrombotic therapies lead to an increased risk of bleeding. Antithrombotic therapy and revascularization procedures entail an increased hemorrhagic risk that is also linked to having received more vigorous antithrombotic therapies. Therefore, it appears crucial to have specifically targeted scores for a PAD patient to assess bleeding and thrombotic risks. The correct utilization of a risk score will determine the variable risk factors for bleeding that can be corrected or modified, as well as identify patients at high risk that require regular reexamination and follow-up. Clinical risk scores do not represent the absolute reality, and inter-score variability must be taken into account. Moreover, several risk scores have been created to be basic and to facilitate and improve clinical decisions in daily practice. Many risk scores based on points vary according to the configuration of the studies, population type, and ethnic group, and many of the risk factor elements in a specific score are unlikely to sustain same weight for that risk. The best approach continues to be devising an uncomplicated, functional, validated, and precise score that can be adjusted to different clinical contexts and populations, while considering the mutable composition of clinical risk.
Cultivation and Uses of Moringa oleifera as Non-Conventional Feed Stuff in Livestock Production: A Review
Authors: Abdoun Khalid , Alsagan Ahmed , Altahir Osman , Suliman Gamaleldin , Al-Haidary Ahmed , Alsaiady Mohammed
Published: December 2022

M. oleifera is the best known and the most utilized of the 14 known species of the genus Moringa. Moringa is used as animal fodder and a medicinal plant as well as in the purification of water. Studies have shown that the day/night temperature of 30/20 °C is the most favorable for M. oleifera germination, plant growth and development. M. oleifera plants prefer sandy, well-drained loam soils due to their susceptibility to waterlogged soil conditions. It is recommended to use fertilizers to improve plant growth and the amount of forage production in areas with low rainfall and extreme temperatures. For forage production, an area of 20 × 20 cm is adapted to 16,000 plants per hectare. Chemical analyses confirmed the presence of different groups of pharmacologically active chemical compounds, as well as functional compounds of nutritional value such as carbohydrates, proteins, fats and vitamins, in M. oleifera. The reviewed literature particularly encourages the use of M. oleifera whole plants as nonconventional forage in ruminants’ nutrition, as well as using M. oleifera leaves or leaves extract as a protein source for broilers and laying hens. M. oleifera in livestock feed with the ultimate goal of producing functional food (meat, eggs and milk) with appropriate contents of human health-promoting substances such as omega-3 and organic selenium remains to be elucidated. Furthermore, M. oleifera inclusion in livestock feed has the potential to increase the shelf-life of animal products during storage and processing. Further research is needed to determine the appropriate supplementation level of different plant parts or their extracts, as well as the appropriate processing methods or treatments of M. oleifera, in order to improve its palatability and consequently enhance the production performance of livestock without compromising animal health.
Who Seeks Clear Aligner Therapy? A European Cross-National Real-World Data Analysis
Authors: Baxmann Martin , Timm Lan Huong , Schwendicke Falk
Published: December 2022

A key step prior to clear aligner therapy (CAT) is the clinical examination and case selection, which includes understanding the specific orthodontic problem to be managed and the wider evaluation of oral health. Seeking CAT may further differ along sociodemographic parameters or across countries, as may perceived orthodontic treatment needs and oral health. We aimed to characterize patients seeking CAT across five European countries. Anonymized real-life data from one large CAT provider (DrSmile, Berlin, Germany) was retrospectively sampled for the period 1 November 2021–31 December 2021. A total of 15,015 patients (68.4% females, 31.6% males, with an age range of 18–81 years, median 30.0 years) were included. The cross-national comparison revealed a significant difference in gender distribution (p < 0.001/Chi-square), with the highest proportion of males in Italy (434/1199, 36.2%) and the lowest in Poland (457/1600, 28.6%); generally, more females sought CAT. The largest motivational factor in all countries for seeking CAT was crowding, in both males and females. By and large, patients paid out of pocket for CAT. The prevalence of caries, periodontitis, and craniomandibular dysfunction as well as the numbers of missing teeth were generally low, albeit with significant differences between sociodemographic groups and countries for caries and periodontitis. Patients seeking CAT showed a low prevalence in oral conditions but differed in their sociodemographic characteristics across countries. Dentists and orthodontists should consider these country-specific differences when planning CAT.
Citric Acid Changes the Fingerprint of Flavonoids and Promotes Their Accumulation in Phellinus igniarius (L.) Quél
Authors: Dong Haoran , Chen Hui , Xu Bing , Tan Yingru , Ling Qun , Shi Liang
Published: December 2022

Phellinus igniarius is a valuable medicinal fungus. P. igniarius is rich in a variety of chemical compounds with medicinal value, among which are flavonoids. Therefore, increasing the content of flavonoids in P. igniarius is beneficial for its potential use in medicinal applications. This study demonstrated that exogenous treatment with citric acid (CA) could significantly increase flavonoid accumulation in P. igniarius. Additionally, we found that CA induced the biosynthesis of flavonoids in a concentration- and time-dependent manner. The flavonoid content could be increased up to 60.96 mg/g when using the treatment with 2.77 mM citric acid for 69.74 h, which was determined by using the response surface method. The changes in the fingerprint profiles of P. igniarius flavonoids with the treatment of CA as an exogenous inducer were also analyzed. In this study, the effect of citric acid as the exogenous inducer on the flavonoid content of P. igniarius was studied, and the processing conditions were optimized through the surface response curve. This approach provides novel insights and a theoretical basis for the production of high-quality P. igniarius.
Beneficial Effect of Wound Dressings Containing Silver and Silver Nanoparticles in Wound Healing—From Experimental Studies to Clinical Practice
Authors: Rybka Mateusz , Mazurek Łukasz , Konop Marek
Published: December 2022

Impaired wound healing affects hundreds of million people around the world; therefore, chronic wounds are a major problem not only for the patient, but also for already overloaded healthcare systems. Chronic wounds are always very susceptible to infections. Billions of dollars are spent to discover new antibiotics as quickly as possible; however, bacterial resistance against antibiotics is rising even faster. For this reason, a complete shift of the antibacterial treatment paradigm is necessary. The development of technology has allowed us to rediscover well-known agents presenting antimicrobial properties with a better outcome. In this context, silver nanoparticles are a promising candidate for use in such therapy. Silver has many useful properties that can be used in the treatment of chronic wounds, such as anti-bacterial, anti-inflammatory, and anti-oxidative properties. In the form of nanoparticles, silver agents can work even more effectively and can be more easily incorporated into various dressings. Silver-based dressings are already commercially available; however, innovative combinations are still being discovered and very promising results have been described. In this review article, the authors focused on describing experimental and clinical studies exploring dressings containing either silver or silver nanoparticles, the results of which have been published in recent years.
COOBoostR: An Extreme Gradient Boosting-Based Tool for Robust Tissue or Cell-of-Origin Prediction of Tumors
Authors: Yang Sungmin , Ha Kyungsik , Song Woojeung , Fujita Masashi , Kübler Kirsten , Polak Paz , Hiyama Eiso , Nakagawa Hidewaki , Kim Hong-Gee , Lee Hwajin
Published: December 2022

We present here COOBoostR, a computational method designed for the putative prediction of the tissue- or cell-of-origin of various cancer types. COOBoostR leverages regional somatic mutation density information and chromatin mark features to be applied to an extreme gradient boosting-based machine-learning algorithm. COOBoostR ranks chromatin marks from various tissue and cell types, which best explain the somatic mutation density landscape of any sample of interest. A specific tissue or cell type matching the chromatin mark feature with highest explanatory power is designated as a potential tissue- or cell-of-origin. Through integrating either ChIP-seq based chromatin data, along with regional somatic mutation density data derived from normal cells/tissue, precancerous lesions, and cancer types, we show that COOBoostR outperforms existing random forest-based methods in prediction speed, with comparable or better tissue or cell-of-origin prediction performance (prediction accuracy—normal cells/tissue: 76.99%, precancerous lesions: 95.65%, cancer cells: 89.39%). In addition, our results suggest a dynamic somatic mutation accumulation at the normal tissue or cell stage which could be intertwined with the changes in open chromatin marks and enhancer sites. These results further represent chromatin marks shaping the somatic mutation landscape at the early stage of mutation accumulation, possibly even before the initiation of precancerous lesions or neoplasia.
Tetra(phenylethynyl)tin Is a New Reagent for Solvent-Free Alkynylation of Imines
Authors: Levashov Andrey S. , Dvirnaya Elena V. , Konshina Dzhamilay N. , Konshin Valery V.
Published: December 2022

The first ZnCl2-catalyzed alkynylation of aldimines with tetra(phenylethynyl)tin was achieved under solvent-free conditions. The present methodology provides propargylamines in 38–62% yields.
Fabrication of r-GO/GO/α-Fe2O3/Fe2TiO5 Nanocomposite Using Natural Ilmenite and Graphite for Efficient Photocatalysis in Visible Light
Authors: Usgodaarachchi Leshan , Jayanetti Madara , Thambiliyagodage Charitha , Liyanaarachchi Heshan , Vigneswaran Saravanamuthu
Published: December 2022

Hematite (α-Fe2O3) and pseudobrookite (Fe2TiO5) suffer from poor charge transport and a high recombination effect under visible light irradiation. This study investigates the design and production of a 2D graphene-like r-GO/GO coupled α-Fe2O3/Fe2TiO5 heterojunction composite with better charge separation. It uses a simple sonochemical and hydrothermal approach followed by L-ascorbic acid chemical reduction pathway. The advantageous band offset of the α-Fe2O3/Fe2TiO5 (TF) nanocomposite between α-Fe2O3 and Fe2TiO5 forms a Type-II heterojunction at the Fe2O3/Fe2TiO5 interface, which efficiently promotes electron-hole separation. Importantly, very corrosive acid leachate resulting from the hydrochloric acid leaching of ilmenite sand, was successfully exploited to fabricate α-Fe2O3/Fe2TiO5 heterojunction. In this paper, a straightforward synthesis strategy was employed to create 2D graphene-like reduced graphene oxide (r-GO) from Ceylon graphite. The two-step process comprises oxidation of graphite to graphene oxide (GO) using the improved Hummer’s method, followed by controlled reduction of GO to r-GO using L-ascorbic acid. Before the reduction of GO to the r-GO, the surface of TF heterojunction was coupled with GO and was allowed for the controlled L-ascorbic acid reduction to yield r-GO/GO/α-Fe2O3/Fe2TiO5 nanocomposite. Under visible light illumination, the photocatalytic performance of the 30% GO/TF loaded composite material greatly improved (1240 Wcm−2). Field emission scanning electron microscopy (FE-SEM) and high-resolution transmission electron microscopy (HR-TEM) examined the morphological characteristics of fabricated composites. X-ray photoelectron spectroscopy (XPS), Raman, X-ray diffraction (XRD), X-ray fluorescence (XRF), and diffuse reflectance spectroscopy (DRS) served to analyze the structural features of the produced composites.
Research on Mechanical Properties of Origami Aluminum Honeycomb for Automobile Energy Absorbing Box
Authors: Wei Wei , Zhang Fengqiang , Xing Youdong , Wang Hongxiang , Liu Rongqiang
Published: December 2022

With the increasing number of automobiles on the road, passive safety has become a particularly important issue. In this paper, an energy-absorbing material, origami aluminum honeycomb, was manufactured by a welding process for use as an automobile energy absorbing box. The mechanical properties and deformation of welded origami aluminum honeycomb in three directions were studied through quasi-static and dynamic compression tests. The results show that the origami aluminum honeycomb had good mechanical energy absorption performance, and the optimal directions are identified. Combined with theoretical analysis, the errors between experiments and simulations are shown. The origami honeycomb structure was designed for use as an automobile energy absorbing box. Analysis shows that it could absorb at least 10% of the kinetic energy of a vehicle during a collision, and could play a role in protecting the interior of the vehicle.
Scavenging of Organic Pollutant and Fuel Generation through Cost-Effective and Abundantly Accessible Rust: A Theoretical Support with DFT Simulations
Authors: Khan Nisar , Gul Tamanna , Khan Idrees , Alabbad Eman A. , Ali Shahid , Saeed Khalid , Khan Ibrahim
Published: December 2022

Waste management and energy generation are the foremost concerns due to their direct relationship with biological species and the environment. Herein, we report the utilization of iron rust (inorganic pollutant) as a photocatalyst for the photodegradation of methylene blue (MB) dye (organic pollutant) under visible light (economic) and water oxidation (energy generation). Iron rust was collected from metallic pipes and calcined in the furnace at 700 °C for 3 h to remove the moisture/volatile content. The uncalcined and calcined rust NPs are characterized through scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS), Fourier-transform infrared (FTIR) analysis, X-ray Diffraction (XRD), and thermogravimetric analysis (TGA). The morphological study illustrated that the shape of uncalcined and calcined iron rust is spongy, porous, and agglomerated. The XRD and DLS particle sizes are in a few hundred nanometers range. The photodegradation (PD) investigation shows that calcined rust NPs are potent for the PD of modeled MB, and the degradation efficiency was about 94% in a very short time of 11 min. The photoelectrochemical (PEC) measurements revealed that calcined rust NPs are more active than uncalcined rust under simulated 1 SUN illumination with the respective photocurrent densities of ~0.40 and ~0.32 mA/cm2. The density functional theory simulations show the chemisorption of dye molecules over the catalyst surface, which evinces the high catalytic activity of the catalyst. These results demonstrate that cheaper and abundantly available rust can be useful for environmental and energy applications.
The Activation Energy of Strain Bursts during Nanoindentation Creep on Polyethylene
Authors: Ghomsheh Mohammad Zare , Khatibi Golta
Published: December 2022

In the present investigation, statistical characterization of strain bursts observed during the load-controlled deformation of high-density polyethylene (HDPE), which arise within the crystalline phase during plastic deformation, was carried out via high-resolution nanoindentation creep experiments. Discrete deformation processes occurred during the nanoindentation creep tests, which indicated that they arose from the break-off of dislocation avalanches, i.e., dislocation climb is a possible mechanism for indentation creep deformation. Characterization of the strain bursts, in terms of the associated height and number, demonstrated that these quantities followed a Gaussian distribution depending on the load and loading rate. This analysis enabled the accurate measurement of creep activation energy. Our method used nanoindentation tests to measure the creep activation energy of HDPE within both the crystalline and amorphous phases. The activation energy of the creep process within the crystalline phase was evaluated using two methods. The frequency of jumps within the crystalline phase, as a function of the strain rate, showed two peaks related to the 5 nm and 10 nm jump sizes that corresponded to the block size within the crystalline lamellae. The results indicated that the intervals coincided with the mean free path of dislocations and the block grain boundaries acted as dislocation barriers. From the dependence of burst frequency on the strain rate and temperature, the activation energy and thermally activated length of the dislocation segment for the plastic slip activation were determined to be 0.66 eV and 20 nm, respectively. Both numbers fit well to the Peterson’s model for the nucleation and motion of thermally activated dislocation segments. A similar activation energy resulted from the differential mechanical analysis of the literature for the αI—transition, which occurred near room temperature in polyethylene. The transition was described as the generation of screw dislocation and its motion along a block grain boundary; therefore, this process is suggested to be the basic mechanism underlying the strain bursts observed in this study.
Effects of Solvent Additive and Micro-Patterned Substrate on the Properties of Thin Films Based on P3HT:PC70BM Blends Deposited by MAPLE
Authors: Socol Marcela , Preda Nicoleta , Breazu Carmen , Petre Gabriela , Stanculescu Anca , Stavarache Ionel , Popescu-Pelin Gianina , Stochioiu Andrei , Socol Gabriel , Iftimie Sorina , Thanner Christine , Rasoga Oana
Published: December 2022

Lately, there is a growing interest in organic photovoltaic (OPV) cells due to the organic materials’ properties and compatibility with various types of substrates. However, their efficiencies are low relative to the silicon ones; therefore, other ways (i.e., electrode micron/nanostructuring, synthesis of new organic materials, use of additives) to improve their performances are still being sought. In this context, we studied the behavior of the common organic bulk heterojunction (P3HT:PC70BM) deposited by matrix-assisted pulsed laser evaporation (MAPLE) with/without 0.3% of 1,8-diiodooctane (DIO) additive on flat and micro-patterned ITO substrates. The obtained results showed that in the MAPLE process, a small quantity of additive can modify the morphology of the organic films and decrease their roughness. Besides the use of the additive, the micro-patterning of the electrode leads to a greater increase in the absorption of the studied photovoltaic structures. The inferred values of the filling factors for the measured cells in ambient conditions range from 19% for the photovoltaic structures with no additive and without substrate patterning to 27% for the counterpart structures with patterning and a small quantity of additive.
Efficient Propylene/Ethylene Separation in Highly Porous Metal–Organic Frameworks
Authors: Liu Xiao-Min , Xie Lin-Hua , Wu Yufeng
Published: December 2022

Light olefins are important raw materials in the petrochemical industry for the production of many chemical products. In the past few years, remarkable progress has been made in the synthesis of light olefins (C2–C4) from methanol or syngas. The separation of light olefins by porous materials is, therefore, an intriguing research topic. In this work, single-component ethylene (C2H4) and propylene (C3H6) gas adsorption and binary C3H6/C2H4 (1:9) gas breakthrough experiments have been performed for three highly porous isostructural metal–organic frameworks (MOFs) denoted as Fe2M-L (M = Mn2+, Co2+, or Ni2+), three representative MOFs, namely ZIF-8 (also known as MAF-4), MIL-101(Cr), and HKUST-1, as well as an activated carbon (activated coconut charcoal, SUPELCO©). Single-component gas adsorption studies reveal that Fe2M-L, HKUST-1, and activated carbon show much higher C3H6 adsorption capacities than MIL-101(Cr) and ZIF-8, HKUST-1 and activated carbon have relatively high C3H6/C2H4 adsorption selectivity, and the C2H4 and C3H6 adsorption heats of Fe2Mn-L, MIL-101(Cr), and ZIF-8 are relatively low. Binary gas breakthrough experiments indicate all the adsorbents selectively adsorb C3H6 from C3H6/C2H4 mixture to produce purified C2H4, and 842, 515, 504, 271, and 181 cm3 g−1 C2H4 could be obtained for each breakthrough tests for HKUST-1, activated carbon, Fe2Mn-L, MIL-101(Cr), and ZIF-8, respectively. It is worth noting that C3H6 and C2H4 desorption dynamics of Fe2Mn-L are clearly faster than that of HKUST-1 or activated carbon, suggesting that Fe2M-L are promising adsorbents for C3H6/C2H4 separation with low energy penalty in regeneration.
Polymer Composites with Self-Regulating Temperature Behavior: Properties and Characterization
Authors: Setnescu Radu , Lungulescu Eduard-Marius , Marinescu Virgil Emanuel
Published: December 2022

A novel conductive composite material with homogeneous binary polymer matrix of HDPE (HD) and LLDPE (LLD), mixed with conductive filler consisting of carbon black (CB) and graphite (Gr), was tested against a HDPE composite with a similar conductive filler. Even the concentration of the conductive filler was deliberately lower for (CB + Gr)/(LLD + HD), and the properties of this composite are comparable or better to those of (CB + Gr)/HD. The kinetic parameters of the ρ-T curves and from the DSC curves indicate that the resistivity peak is obtained when the polymer matrix is fully melted. When subjected to repeated thermal cycles, the composite (CB + Gr)/(LLD + HD) presented a better electrical behavior than composite CB + Gr)/HD, with an increase in resistivity (ρmax) values with the number of cycles, as well as less intense NTC (Negative Temperature Coefficient) effects, both for the crosslinked and thermoplastic samples. Radiation crosslinking led to increased ρmax values, as well as to inhibition of NTC effects in both cases, thus having a clear beneficial effect. Limitation effects of surface temperature and current intensity through the sample were observed at different voltages, enabling the use of these materials as self-regulating heating elements at various temperatures below the melting temperature. The procedure based on physical mixing of the components appears more efficient in imparting lower resistivity in solid state and high PTC (Positive Temperature Coefficient) effects to the composites. This effect is probably due to the concentration of the conductive particles at the surface of the polymer domains, which would facilitate the formation of the conductive paths. Further work is still necessary to optimize both the procedure of composite preparation and the properties of such materials.
Porcelain versus Porcelain Stoneware: So Close, So Different. Sintering Kinetics, Phase Evolution, and Vitrification Paths
Authors: Conte Sonia , Molinari Chiara , Ardit Matteo , Cruciani Giuseppe , Dondi Michele , Zanelli Chiara
Published: December 2022

Five porcelain and porcelain stoneware bodies were investigated to compare sintering mechanisms and kinetics, phase and microstructure evolution, and high temperature stability. All batches were designed with the same raw materials and processing conditions, and characterized by optical dilatometry, XRF, XRPD-Rietveld, FEG-SEM and technological properties. Porcelain and porcelain stoneware behave distinctly during sintering, with the convolution of completely different phase evolution and melt composition/structure. The firing behavior of porcelain is essentially controlled by microstructural features. Changes in mullitization create conditions for a relatively fast densification rate at lower temperature (depolymerized melt, lower solid load) then to contrast deformations at high temperature (enhanced effective viscosity by increasing solid load, mullite aspect ratio, and melt polymerization). In porcelain stoneware, the sintering behavior is basically governed by physical and chemical properties of the melt, which depend on the stability of quartz and mullite at high temperature. A buffering effect ensures adequate effective viscosity to counteract deformation, either by preserving a sufficient skeleton or by increasing melt viscosity if quartz is melted. When a large amount of soda–lime glass is used, no buffering effect occurs with melting of feldspars, as both solid load and melt viscosity decrease. In this batch, the persistence of a feldspathic skeleton plays a key role to control pyroplasticity.
Effective Halogen-Free Flame-Retardant Additives for Crosslinked Rigid Polyisocyanurate Foams: Comparison of Chemical Structures
Authors: Lenz Johannes U. , Pospiech Doris , Komber Hartmut , Korwitz Andreas , Kobsch Oliver , Paven Maxime , Albach Rolf W. , Günther Martin , Schartel Bernhard
Published: December 2022

The impact of phosphorus-containing flame retardants (FR) on rigid polyisocyanurate (PIR) foams is studied by systematic variation of the chemical structure of the FR, including non-NCO-reactive and NCO-reactive dibenzo[d,f][1,3,2]dioxaphosphepine 6-oxide (BPPO)- and 9,10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide (DOPO)-containing compounds, among them a number of compounds not reported so far. These PIR foams are compared with PIR foams without FR and with standard FRs with respect to foam properties, thermal decomposition, and fire behavior. Although BPPO and DOPO differ by just one oxygen atom, the impact on the FR properties is very significant: when the FR is a filler or a dangling (dead) end in the PIR polymer network, DOPO is more effective than BPPO. When the FR is a subunit of a diol and it is fully incorporated in the PIR network, BPPO delivers superior results.
Synthesis and Characterization of Novel Ternary-Hybrid Nanoparticles as Thermal Additives
Authors: Mohammed Zayan Jalal , Rasheed Abdul Khaliq , John Akbar , Faris Waleed Fekry , Aabid Abdul , Baig Muneer , Alallam Batoul
Published: December 2022

The performance of water as a heat transfer medium in numerous applications is limited by its effective thermal conductivity. To improve the thermal conductivity of water, herein, we report the development and thermophysical characterization of novel metal-metal-oxide-carbon-based ternary-hybrid nanoparticles (THNp) GO-TiO2-Ag and rGO-TiO2-Ag. The results indicate that the graphene oxide- and reduced graphene oxide-based ternary-hybrid nanoparticles dispersed in water enhance the base fluid (H2O) thermal conductivity by 66% and 83%, respectively, even at very low concentrations. Mechanisms contributing to this significant enhancement are discussed. The experimental thermal conductivity is plotted against the existing empirical hybrid thermal conductivity correlations. We found that those correlations are not suitable for the metal-metal-oxide-carbon combinations, calling for new thermal conductivity models. Furthermore, the rheological measurements of the nanofluids display non-Newtonian behavior, and the viscosity reduces with the increase in temperature. Such behavior is possibly due to the non-uniform shapes of the ternary-hybrid nanoparticles.
Use of Hybrid Mineral Filler with High Emissivity in Asphalt Mixture for Cooling Road Pavements
Authors: Kong Lingxiang , Xu Ling , Du Yinfei , Jin Jiao , Loprencipe Giuseppe , Moretti Laura
Published: December 2022

Road asphalt pavements cover a high percentage of urban size and contribute to heat islands. This study proposed a new method to cool asphalt pavement by incorporating a kind of hybrid mineral filler (HMF) with high emissivity into a reference asphalt mixture prepared with limestone mineral filler (LMF). The physical, emissive, solar reflective, and rheological properties of asphalt mastic and the thermal performances of asphalt mixture were covered to investigate the possibility of the proposed strategy. From Fourier transform infrared spectrum test, it can be found that HMF was physically blended with asphalt. The emissivity results show that HMF increased the emissivity of asphalt mastic from 0.9204 to 0.9820. The asphalt mastic containing HMF had similar solar reflectance with the control one. In addition, HMF could enhance the rutting resistance of asphalt mastic according to the results of multiple stress creep recovery tests. When HMF replaced LMF, the thermal conductivity of the asphalt mixture with HMF increased by 0.26 W/(m·K) (the reference value was 1.72 W/(m·K)). The combined effect of high emissivity and thermal conductivity led to a lower surface temperature (i.e., −5.4 °C) in the tests. The results of this study demonstrate that HMF is a potential material to cool asphalt pavements.