bluuebunny/crossref_metadata_2025 huggingface dataset:
Effect of Organic Manures on Growth, Yield, Leaf Nutrient Uptake and Soil Properties of Kiwifruit (Actinidia deliciosa Chev.) cv. Allison
Authors: Sharma Sunny , Rana Vishal Singh , Rana Neerja , Sharma Umesh , Gudeta Kasahun , Alharbi Khadiga , Ameen Fuad , Bhat Sartaj Ahmad
Published: December 2022

In recent decades, organic kiwifruit farming has come up as a feasible method for high-quality kiwi production without using chemical fertilizers. The primary objective of this research was to investigate how the sole application of organic and the combined application of organic manures affected the growth, yields, and quality of Allison kiwifruit, as well as the soil’s physicochemical characteristics. The field trial was conducted on cv. Allison to determine the efficacy of organic manures (OM) on growth, nutrient absorption, production and soil health. The experiment involved eight treatments, viz.: T1: 100% Dairy manure (DM); T2: 100% Vermicompost (VC); T3: 100% chicken manure (CM); T4: 50% DM + 50% CM; T5: 50% DM + 50% VC; T6: 50% CM + 50% VC; T7: DM + CM + VC in equal proportions; and T8: Recommended nutrients inorganic NPK + 40 kg DM. A randomized complete block design comprising three replicas was used in this investigation. The use of inorganic fertilizers (NPK) in combination with DM enhanced Spad Values Chlorophyll, fruit production, leaf number, leaf area, and stem diameter while also improving the soil’s chemical characteristics. The flower initiation was recorded with DM and Vermicompost (50:50). Furthermore, when compared to inorganic fertilizer treatment, OM treatment significantly improved fruit quality by improving fruit chemical composition in terms of soluble solids contents and leaf nutrient status, as well as improving soil’s physical properties with DM and Vermicompost (50:50). The study’s outcome revealed that OM had a significant impact on flowering time, fruit SSC, leaf nutritional status, and soil physical characteristics. In comparison to organic treatments, recommended fertilizer dosages (NPK + DM) improved plant growth, fruit yield, and soil chemical characteristics.
Production of Fluorescent Dissolved Organic Matter by Microalgae Strains from the Ob and Yenisei Gulfs (Siberia)
Authors: Lobus Nikolay V. , Glushchenko Anton M. , Osadchiev Alexander A. , Maltsev Yevhen I. , Kapustin Dmitry A. , Konovalova Olga P. , Kulikovskiy Maxim S. , Krylov Ivan N. , Drozdova Anastasia N.
Published: December 2022

Dissolved organic matter (DOM) is an important component of aquatic environments; it plays a key role in the biogeochemical cycles of many chemical elements. Using excitation–emission matrix fluorescence spectroscopy, we examined the fluorescent fraction of DOM (FDOM) produced at the stationary phase of growth of five strains of microalgae sampled and isolated from the Ob and Yenisei gulfs. Based on the morphological and molecular descriptions, the strains were identified as diatoms (Asterionella formosa, Fragilaria cf. crotonensis, and Stephanodiscus hantzschii), green microalgae (Desmodesmus armatus), and yellow-green microalgae (Tribonema cf. minus). Three fluorescent components were validated in parallel factor analysis (PARAFAC): one of them was characterized by protein-like fluorescence (similar to peak T), two others, by humic-like fluorescence (peaks A and C). The portion of fluorescence intensity of humic compounds (peak A) to the total fluorescence intensity was the lowest (27 ± 5%) and showed little variation between species. Protein-like fluorescence was most intense (45 ± 16%), but along with humic-like fluorescence with emission maximum at 470 nm (28 ± 14%), varied considerably for different algae strains. The direct optical investigation of FDOM produced during the cultivation of the studied algae strains confirms the possibility of autochthonous production of humic-like FDOM in the Arctic shelf regions.
Role of Endogenous Salicylic Acid as a Hormonal Intermediate in the Bacterial Endophyte Bacillus subtilis-Induced Protection of Wheat Genotypes Contrasting in Drought Susceptibility under Dehydration
Authors: Lastochkina Oksana , Ivanov Sergey , Petrova Svetlana , Garshina Darya , Lubyanova Alsu , Yuldashev Ruslan , Kuluev Bulat , Zaikina Evgenia , Maslennikova Dilara , Allagulova Chulpan , Avtushenko Irina , Yakupova Albina , Farkhutdinov Rashit
Published: December 2022

Endophytic Bacillus subtilis is a non-pathogenic beneficial bacterium which promotes plant growth and tolerance to abiotic stresses, including drought. However, the underlying physiological mechanisms are not well understood. In this study, the potential role that endogenous salicylic acid (SA) plays in regulating endophytic B. subtilis-mediated drought tolerance in wheat (Triticum aestivum L.) was examined. The study was conducted on genotypes with contrasting levels of intrinsic drought tolerance (drought-tolerant (DT) cv. Ekada70; drought-susceptible (DS) cv. Salavat Yulaev). It was revealed that B. subtilis 10-4 promoted endogenous SA accumulation and increased the relative level of transcripts of the PR-1 gene, a marker of the SA-dependent defense pathway, but two wheat cultivars responded differently, with the highest levels exhibited in DT wheat seedlings. These had a positive correlation with the ability of strain 10-4 to effectively protect DT wheat seedlings against drought injury by decreasing osmotic and oxidative damages (i.e., proline, water holding capacity (WHC), and malondialdehyde (MDA)). However, the use of the SA biosynthesis inhibitor 1-aminobenzotriazole prevented endogenous SA accumulation under normal conditions and the maintenance of its increased level under stress as well as abolished the effects of B. subtilis treatment. Particularly, the suppression of strain 10-4-induced effects on proline and WHC, which are both contributing factors to dehydration tolerance, was found. Moreover, the prevention of strain 10-4-induced wheat tolerance to the adverse impacts of drought, as judged by the degree of membrane lipid peroxidation (MDA) and plant growth (length, biomass), was revealed. Thus, these data provide an argument in favor of a key role of endogenous SA as a hormone intermediate in triggering the defense responses by B. subtilis 10-4, which also afford the foundation for the development of the bacterial-induced tolerance of these two different wheat genotypes under dehydration.
Effects of Different Fertilizer Treatments, Environment and Varieties on the Yield-, Grain-, Flour-, and Dough-Related Traits and Cookie Quality of Weak-Gluten Wheat
Authors: Wu Hongya , Wang Zunjie , Zhang Xiao , Wang Junchan , Hu Wenjing , Wang Hui , Gao Derong , Souza Edword , Cheng Shunhe
Published: December 2022

Weak-gluten wheat is the main raw material for crisp and soft foods such as cookies, cakes, and steamed breads in China. However, it remains challenging to find an appropriate fertilization regime to balance the yield and quality of wheat for special uses (such as cookie making). Here, four nitrogen (N) fertilizer treatments were compared in terms of effects on the yield-, grain-, flour-, and dough-related traits and cookie quality of nine weak-gluten wheat varieties. Compared with other treatments, the treatment M (which had 180 kg ha−1 N fertilizers with basal fertilizer:tillering fertilizer:jointing fertilizer = 5:1:4) was a superior fertilization strategy as it could ensure a higher yield (4.46 kg block−1) and proper traits related to cookie quality. Moreover, environmental conditions and wheat genotypes exhibited significant effects on many quality-related traits. The quality of Chinese crisp biscuits showed a significant association with unit weight, redness, and solvent retention capacity in lactic acid solution, while that of American cookies was influenced by thousand-grain weight, hardness, rate of yield flour, and formation time as indicated by the Mantel test. Additional Pearson correlation analysis demonstrated that thousand-grain weight, hardness, and rate of yield flour can affect the quality of American cookies. Our findings demonstrate that it is necessary to comprehensively consider local conditions, variety selection, and optimal fertilization to achieve high-quality weak-gluten wheat for cookie making.
Paeonia × suffruticosa (Moutan Peony)—A Review of the Chemical Composition, Traditional and Professional Use in Medicine, Position in Cosmetics Industries, and Biotechnological Studies
Authors: Ekiert Halina , Klimek-Szczykutowicz Marta , Szopa Agnieszka
Published: December 2022

The aim of this review is to perform a systematic review of scientific papers and an in-depth analysis of the latest research related to Paeonia × suffruticosa Andrews as a valuable plant species, important in pharmacy and cosmetology. P. × suffruticosa bark root-Moutan cortex is a medicinal raw material formerly known from traditional Chinese medicine (TCM) but less common in official European medicine. It was introduced for the first time in the European Pharmacopoeia Supplement 9.4 in 2018. In this work, the numerous possible applications of this raw material were depicted based on modern professional pharmacological studies documenting its very valuable medicinal values, including antioxidant, cytoprotective, anti-cancer, anti-inflammatory, cardioprotective, anti-atherosclerotic, anti-diabetic and hepatoprotective activities. The scientific studies indicated that the profile of raw material activity is mainly due to paeonol, paeoniflorin and 1,2,3,4,6-penta-O-galloyl-β-D-glucopyranose. Moreover, the significance of this plant (its different organs) in the production of cosmetics was underlined. P. × suffruticosa finds increasing application in cosmetology due to research on its chronic dermatitis, anti-aging and brightening effects. Furthermore, some biotechnological research has been described aimed at developing effective in vitro micropropagation protocols for P. × suffruticosa.
Conservation Assessment and Chemistry of Boswellia ogadensis, a Critically Endangered Frankincense Tree
Authors: Johnson Stephen , Abdikadir Abdinasir , Satyal Prabodh , Poudel Ambika , Setzer William N.
Published: December 2022

Boswellia ogadensis is a critically endangered species of frankincense tree, restricted to a small area of the Shabelle river valley in southern Ethiopia. It has only been recorded from two botanical collecting trips, in 1972 and 2006, with no indication of the abundance, threats, or population status of the trees, and it was listed on the IUCN Red List of Endangered Species as “Critically Endangered” in 2018. More recent expeditions, in 2019 and 2021, were not able to locate the species, raising concerns about its continued survival. We carried out a field survey in June 2022 to re-locate the species, assess the threat level it is facing, and collect samples of resin for analysis. This survey revealed that B. ogadensis is present in more locations than previously recorded, and is more abundant than thought. While it is facing multiple threats, including grazing, cutting for firewood, and insect attacks, these threats vary geographically, and there are populations that appear to be healthy and regenerating well. While more research is needed, the current survey indicates that downlisting to “Endangered” status may be appropriate. Samples of resin were also collected and analyzed using gas chromatographic techniques, revealing that while the essential oil profile is similar to that of other Boswellia species (dominated by α-thujene, α-pinene, p-cymene, and terpenin-4-ol), there are chemical markers that can distinguish it from other sympatric Boswellia species, indicating the potential for this to be used as a tool to monitor whether B. ogadensis is being harvested alongside other more common Boswellia species.
Phytotoxic Metabolites Produced by Fungi Involved in Grapevine Trunk Diseases: Progress, Challenges, and Opportunities
Authors: Reveglia Pierluigi , Billones-Baaijens Regina , Savocchia Sandra
Published: December 2022

Grapevine trunk diseases (GTDs), caused by fungal pathogens, are a serious threat to vineyards worldwide, causing significant yield and economic loss. To date, curative methods are not available for GTDs, and the relationship between the pathogen and symptom expression is poorly understood. Several plant pathologists, molecular biologists, and chemists have been investigating different aspects of the pathogenicity, biochemistry, and chemical ecology of the fungal species involved in GTDs. Many studies have been conducted to investigate virulence factors, including the chemical characterization of phytotoxic metabolites (PMs) that assist fungi in invading and colonizing crops such as grapevines. Moreover, multidisciplinary studies on their role in pathogenicity, symptom development, and plant-pathogen interactions have also been carried out. The aim of the present review is to provide an illustrative overview of the biological and chemical characterization of PMs produced by fungi involved in Eutypa dieback, Esca complex, and Botryosphaeria dieback. Moreover, multidisciplinary investigations on host-pathogen interactions, including those using cutting-edge Omics techniques, will also be reviewed and discussed. Finally, challenges and opportunities in the role of PMs for reliable field diagnosis and control of GTDs in vineyards will also be explored.
The Outline of Seed Silhouettes: A Morphological Approach to Silene (Caryophyllaceae)
Authors: Martín-Gómez José Javier , Rodríguez-Lorenzo José Luis , Tocino Ángel , Janoušek Bohuslav , Juan Ana , Cervantes Emilio
Published: December 2022

Seed morphology is an important source of information for plant taxonomy. Nevertheless, the characters under study are diverse, and a simple, unified method is lacking in the literature. A new method for the classification of seeds of the genus Silene based on optical images and image analysis has recently been described on the basis of morphological measurements of the lateral seed views. According to the outline of their silhouettes, seeds from 52 species (49 of Silene and three related species) were classified in three groups: smooth, rugose and echinate, revealing remarkable differences between these groups. This methodology has been applied here to 51 new species, making a total of 100 species of Silene analyzed so far. According to our data, a new group was described, termed papillose. The results showed morphological differences between the four mentioned seed groups, with reduced values of circularity for dorsal and lateral seed views in the papillose and echinate groups and reduced values of solidity in the papillose seeds. The method was applied to the analysis of individual as well as to average seed silhouettes and some of the differences between groups were maintained in both cases.
Study on Flavonoids and Bioactivity Features of Pericarp of Citrus reticulata “Chachi” at Different Harvest Periods
Authors: Liang Shejian , Zhang Jiongbin , Liu Yufang , Wen Zhijia , Liu Xinxin , Dang Fengliang , Xie Tianxiao , Wang Jingxin , Wang Zhanqian , Wu Hong
Published: December 2022

Dry mature pericarp of Citrus reticulata “Chachi” (PCR), Pericarpium Citri Reticulatae Chachiensis, is a traditional Chinese medicine that displays characteristics of different usage at different harvest times in clinical use. The corresponding changes in the bioactive components in PCR from different harvest times remain unclear. Therefore, in this study, broadly targeted metabolomics technology was used to compare the differences in bioactive components among pericarps of PCR, which are the raw material of PCR at different growth stages. In the results, 210 kinds of flavonoid metabolites were detected. The content of hesperidin in red PCR harvested in December was higher than that in Citri Reticulatae Pericarpium Viride (CRPV) and reddish PCR harvested from July to November. Furthermore, the content of nobiletin, tangeretin, and 3,3′,4′,5,6,7,8-heptamethoxyflavone in CRPV from July to September was higher than that in the PCR harvested at other times. In addition, the result of cluster analysis and PCA showed that CRPV harvested from July to September had an obvious grouping pattern with the reddish PCR and the red PCR harvested from October to December. Differential metabolites in six comparison groups (A1 vs. A6, A1 vs. A2, A2 vs. A3, A3 vs. A4, A4 vs. A5, A5 vs. A6) were 67, 48, 14, 51, 42, and 40, respectively. The common differential metabolite of four comparison groups was 3′,4′,7-trihydroxyflavone (A1 vs. A2, A2 vs. A3, A3 vs. A4, A4 vs. A5). All the flavonoid differential metabolites screened were enriched in 16 metabolic pathways. Moreover, the results of the evaluation of the total antioxidant capacity indicated that CRPV in August was a suitable raw material for the production of antioxidants. Through molecular docking, the content of potential anti-SARS-CoV-2 components in the PCR in October was higher than that in the PCR in other periods. These results further proved that PCR at different harvest times was endowed with different efficacy and usage due to the difference in the accumulation of bioactive components.
High Performance of Titanium Dioxide Reinforced Acrylonitrile Butadiene Rubber Composites
Authors: Chueangchayaphan Wannarat , Luangchuang Piyawadee , Chueangchayaphan Narong
Published: December 2022

Recently, dielectric elastomer actuators (DEA) have emerged as one of the most promising materials for use in soft robots. However, DEA needs a high operating voltage and high mechanical properties. By increasing the dielectric constant of elastomeric materials, it is possible to decrease the operating voltage required. Thus, elastomeric composites with a high dielectric constant and strong mechanical properties are of interest. The aim of this research was to investigate the effect of titanium dioxide (TiO2) content ranging from 0 to 110 phr on the cure characteristics, and physical, dielectric, dynamic mechanical, and morphological properties of acrylonitrile butadiene rubber (NBR) composites. The addition of TiO2 reduced the scorch time (ts1) as well as the optimum cure time (tc90) but increased the cure rate index (CRI), minimum torque (ML), maximum torque (MH), and delta torque (MH − ML). The optimal TiO2 content for maximum tensile strength and elongation at break was 90 phr. Tensile strength and elongation at break were increased by 144.8% and 40.1%, respectively, over pure NBR. A significant mechanical property improvement was observed for TiO2-filled composites due to the good dispersion of TiO2 in the NBR matrix, which was confirmed by scanning electron microscopy (SEM). Moreover, incorporating TiO2 filler gave a higher storage modulus, a shift in glass transition temperature (Tg) to a higher temperature, and reduced damping in dynamic mechanical thermal analysis (DMTA). The addition of TiO2 to NBR rubber increased the dielectric constant of the resultant composites in the tested frequency range from 102 to 105 Hz. As a result, TiO2-filled NBR composite has a high potential for dielectric elastomer actuator applications.
Finite Element Analysis of Flexural Behavior of Shape Memory Alloy Hybrid Composites Laminates
Authors: Xu Lidan , Zhao Jitao , Zhang Xiangyu , Shi Mingfang , Wang Zhenqing
Published: December 2022

In this paper, experiments and finite element analysis methods were adopted to study the flexural performance of shape memory alloy hybrid composites (SMAHC). The effect of embedding content and position of shape memory alloy (SMA) wire on the flexural properties of composite laminates was analyzed, and the optimal content and position of SMA wire were obtained. The optimal number of SMA wires for SMAHC laminates (B-2) is four. Compared with GFRP laminates, the flexural modulus of B-2-4 laminates increases by 5.19%, while the strength decreases by 5.76% on average. The finite element model of the SMAHC laminate was established by using ABAQUS finite element analysis software, and the validity of the model was verified by the comparison between the simulation results and the experimental results. The microscopic morphology results show that the weak interface between the matrix and SMA has a certain influence on the flexural performance of SMAHC specimens.
Effect of Polyvinylidene Fluoride Membrane Production Conditions on Its Structure and Performance Characteristics
Authors: Fomin Sergey , Shirokova Evgenia , Kraeva Iren , Tolstobrov Ivan , Bushuev Andrey , Yuzhanin Kirill , Ananchenko Boris , Vetcher Alexandre A. , Iordanskii Alexey
Published: December 2022

Poly (vinylidene fluoride) membranes were prepared by freeze-casting. The effects of PVDF concentration, and freezing temperature on the morphology, crystallization, and performance of prepared membranes were examined. Polymer concentration was varied from 10 to 25 wt%. The freezing temperature was varied from −5 to −25 °C. Dimethyl sulfoxide (DMSO) and distilled water were used as solvents and non-solvents, respectively. The first step of this study was devoted to estimating the optimal concentration of PVDF solution in DMSO. Membranes prepared at different ratios were characterized using physical and mechanical characteristics and porosity. The second step was to optimize the time required for the production of the membranes. In the third step, it was shown that the freezing temperature had a remarkable effect on the morphology of the membranes: as the temperature decreases, there is a transition from spherulite structures to interconnected pores. It was shown that the diversity in the pore pattern for PVDF affects remarkably the water permeability through the polymer membrane. During the monitoring of the spread of crystallized areas during the formation of the membrane, it was found that the crystallization of the solvent begins at localized points of the microscale, further crystallized areas spread radially or unevenly along the surface of the solution, forming contact borders, which can lead to changes in the properties of the membrane in its area.
Microstructure and Mechanical Properties of Severely Deformed Polypropylene in ECAE (Equal Channel Angular Extrusion) via Routes A and C
Authors: Jiang Qifeng , Boulahia Ramdane , Zaïri Fahmi , Vozniak Iurii , Qu Zhengwei , Gloaguen Jean-Michel , Liu Xiaobing
Published: December 2022

Equal channel angular extrusion (ECAE) is a solid-state extrusion process for modifying microstructures via severe plastic deformation without modifying the specimen cross section. In this study, changes in the microstructure and mechanical properties of polypropylene resulting from extrusion orientation route A (no rotation between extrusions) and extrusion orientation route C (a rotation of 180° between extrusions) are investigated using a 90° die-angle tooling outfitted with back pressure. Important differences are reported for the ECAE-induced deformation behavior between the two processing routes. A focus is made on the occurrence of heterogeneous plastic deformations (periodic shear banding and warping) for both routes and the control and inhibition of the plastic instabilities via regulated back pressure and ram velocity. Wide-angle X-ray scattering is carried out to characterize the structural evolution as a function of the processing conditions including route, extrusion velocity and BP application. The mechanical properties of the specimens machined from the ECAE pieces are examined under different loading paths including uniaxial tension/compression and simple shear. Full-field displacements converted to volumetric strains revealed the profound impacts of the processing route on the deformation mechanisms during tensile deformation.
Computer Simulation of Composite Materials Behavior under Pressing
Authors: Berladir Khrystyna , Zhyhylii Dmytro , Brejcha Jiří , Pozovnyi Oleksandr , Krmela Jan , Krmelová Vladimíra , Artyukhov Artem
Published: December 2022

Composite materials have a wide range of functional properties, which is ensured by using various technological methods of obtaining both the matrix or fillers and the composition as a whole. A special place belongs to the composition formation technology, which ensures the necessary structure and properties of the composite. In this work, a computer simulation was carried out to identify the main dependencies of the behavior of composite materials in the process of the main technological operations of their production: pressing and subsequent sintering. A polymer matrix randomly reinforced with two types of fillers: spherical and short cylindrical inclusions, was used to construct the finite element models of the structure of composites. The ANSYS Workbench package was used as a calculation simulation platform. The true stress–strain curves for tension, Poisson’s ratios, and ultimate stresses for composite materials were obtained using the finite element method based on the micromechanical approach at the first stage. These values were calculated based on the stretching diagrams of the matrix and fillers and the condition of the ideality of their joint operation. At the second stage, the processes of mechanical pressing of composite materials were modelled based on their elastic–plastic characteristics from the first stage. The result is an assessment of the accumulation of residual strains at the stage before sintering. The degree of increase in total strain capability of composite materials after sintering was shown.
Predictive Modeling of Soft Stretchable Nanocomposites Using Recurrent Neural Networks
Authors: García-Ávila Josué , Torres Serrato Diego de Jesus , Rodriguez Ciro A. , Martínez Adriana Vargas , Cedillo Erick Ramírez , Martínez-López J. Israel
Published: December 2022

Human skin is characterized by rough, elastic, and uneven features that are difficult to recreate using conventional manufacturing technologies and rigid materials. The use of soft materials is a promising alternative to produce devices that mimic the tactile capabilities of biological tissues. Although previous studies have revealed the potential of fillers to modify the properties of composite materials, there is still a gap in modeling the conductivity and mechanical properties of these types of materials. While traditional Finite Element approximations can be used, these methodologies tend to be highly demanding of time and processing power. Instead of this approach, a data-driven learning-based approximation strategy can be used to generate prediction models via neural networks. This paper explores the fabrication of flexible nanocomposites using polydimethylsiloxane (PDMS) with different single-walled carbon nanotubes (SWCNTs) loadings (0.5, 1, and 1.5 wt.%). Simple Recurrent Neural Networks (SRNN), Long Short-Term Memory (LSTM), and Gated Recurrent Units (GRU) models were formulated, trained, and tested to obtain the predictive sequence data of out-of-plane quasistatic mechanical tests. Finally, the model learned is applied to a dynamic system using the Kelvin-Voight model and the phenomenon known as the bouncing ball. The best predictive results were achieved using a nonlinear activation function in the SRNN model implementing two units and 4000 epochs. These results suggest the feasibility of a hybrid approach of analogy-based learning and data-driven learning for the design and computational analysis of soft and stretchable nanocomposite materials.
Therapy of Extensive Chronic Skin Defects after a Traumatic Injury Due to Microbial Contamination Using a Surface Implant Made of a Biocompatible Polycaprolactone—A Pilot Case Study
Authors: Findrik Balogová Alena , Kožár Martin , Staroňová Radka , Schnitzer Marek , Dancáková Gabriela , Živčák Jozef , Hudák Radovan
Published: December 2022

This case study describes the use of additive manufacturing technology combining a biodegradable polymer material, polycaprolactone (PCL), and innovative procedures for creating superficial wound dressing, a scaffold in the therapy of extensive contaminated skin defects caused by a traumatic injury. Chronic and contaminated wounds represent a clinical problem and require intensive wound care. The application of a temporary scaffold-facilitated bridging of the wound edges resulted in faster tissue regeneration and a shorter defect closure time, compared to other conservative and surgical methods used in therapy of chronic wounds. Although this procedure has proven to be an optimal alternative to autologous transplants, further studies with a larger number of patients would be beneficial.
Fluorine-Free Hydrophobic Modification and Waterproof Breathable Properties of Electrospun Polyacrylonitrile Nanofibrous Membranes
Authors: Zhang Ling , Sheng Junlu , Yao Yongbo , Yan Zhiyong , Zhai Yunyun , Tang Zhongfeng , Li Haidong
Published: December 2022

Waterproof breathable functional membranes have broad application prospects in the field of outdoors textiles. The fluorine-containing microporous membranes of the mainstream functional products easily cause harm to the environment, and thus, the fluorine-free environmental nanofibrous membranes are an important development direction for functional membranes. In this subject, the electrospun polyacrylonitrile nanofibrous membranes were first hydrophobically modified by amino functional modified polysiloxane (AMP), followed by in situ cross-linking modified with 4, 4’-methyl diphenylene diisocyanate (MDI). The fluorine-free modification by AMP altered the surface of the membranes from hydrophilic to hydrophobic, and greatly improved the waterproof properties with the hydrostatic pressure reaching to 87.6 kPa. In addition, the formation of bonding points and the in situ preparation of polyuria through the reaction between the isocyanate in MDI and the amino group in AMP, could improve the mechanical properties effectively. When using AMP with the concentration of 1 wt% and MDI with the concentration of 2 wt%, the relatively good comprehensive performance was obtained with good water resistance (93.8 kPa), modest vapor permeability (4.7 kg m−2 d−1) and air permeability (12.7 mm/s). Based on these testing data, the modified nanofibrous membranes had excellent waterproof and breathable properties, which has future potential in outdoor sports apparel.
Temperature-Dependent Polymorphism and Phase Transformation of Friction Transferred PLLA Thin Films
Authors: Wu Jinghua , Chen Xing , Hu Jian , Yan Shouke , Zhang Jianming
Published: December 2022

Poly(L-lactic acid) (PLLA) thin films with a highly oriented structure, successfully prepared by a fast friction transfer technique, were investigated mainly on the basis of synchrotron radiation wide-angle X-ray diffraction (WAXD) and Fourier transform infrared spectroscopy (FTIR). The crystalline structure of the highly oriented PLLA film was remarkably affected by friction transfer temperatures, which exhibited various crystal forms in different friction temperature regions. Interestingly, metastable β-form was generated at all friction transfer temperatures (70–140 °C) between Tg and Tm, indicating that fast friction transfer rate was propitious to the formation of β-form. Furthermore, the relative content among β-, α′-, and α-forms at different friction temperatures was estimated by WAXD as well as FTIR spectroscopy. In situ temperature-dependent WAXD was applied to reveal the complicated phase transition behavior of PLLA at a friction transfer temperature of 100 °C. The results illustrated that the contents of β- and α′-forms decreased in turn, whereas the α-form increased in content due to partially melt-recrystallization or crystal perfection. Moreover, by immersing into a solvent of acetone, β-, α′-form were transformed into stable α-crystalline form directly as a consequence. The highly oriented structure was maintained with the chain perfectly parallel to friction transfer direction after acetone treatment, evidenced by polarized FTIR and polarized optical microscopy (POM) measurements.
Chitosan-Coated Polymeric Silver and Gold Nanoparticles: Biosynthesis, Characterization and Potential Antibacterial Applications: A Review
Authors: Huq Md. Amdadul , Ashrafudoulla Md. , Parvez Md. Anowar Khasru , Balusamy Sri Renukadevi , Rahman Md. Mizanur , Kim Ji Hyung , Akter Shahina
Published: December 2022

Biosynthesized metal nanoparticles, especially silver and gold nanoparticles, and their conjugates with biopolymers have immense potential in various fields of science due to their enormous applications, including biomedical applications. Polymeric nanoparticles are particles of small sizes from 1 nm to 1000 nm. Among different polymeric nanoparticles, chitosan-coated silver and gold nanoparticles have gained significant interest from researchers due to their various biomedical applications, such as anti-cancer, antibacterial, antiviral, antifungal, anti-inflammatory technologies, as well as targeted drug delivery, etc. Multidrug-resistant pathogenic bacteria have become a serious threat to public health day by day. Novel, effective, and safe antibacterial agents are required to control these multidrug-resistant pathogenic microorganisms. Chitosan-coated silver and gold nanoparticles could be effective and safe agents for controlling these pathogens. It is proven that both chitosan and silver or gold nanoparticles have strong antibacterial activity. By the conjugation of biopolymer chitosan with silver or gold nanoparticles, the stability and antibacterial efficacy against multidrug-resistant pathogenic bacteria will be increased significantly, as well as their toxicity in humans being decreased. In recent years, chitosan-coated silver and gold nanoparticles have been increasingly investigated due to their potential applications in nanomedicine. This review discusses the biologically facile, rapid, and ecofriendly synthesis of chitosan-coated silver and gold nanoparticles; their characterization; and potential antibacterial applications against multidrug-resistant pathogenic bacteria.
Polyurethane Adhesives Based on Oxyalkylated Kraft Lignin
Authors: Vieira Fernanda Rosa , Gama Nuno , Magina Sandra , Barros-Timmons Ana , Evtuguin Dmitry V. , Pinto Paula C. O. R.
Published: December 2022

Lignin-based polyol was obtained via oxyalkylation reaction with propylene carbonate using eucalyptus kraft lignin isolated from the industrial cooking liquor by the Lignoboost® procedure. This lignin-based polyol (LBP) was used without purification in the preparation of polyurethane (PU) adhesives combined with polymeric 4,4′-methylenediphenyl diisocyanate (pMDI). A series of adhesives were obtained by varying the NCO/OH ratio of PU counterparts (pMDI and LBPs) and their performance was evaluated by gluing wood pieces under predefined conditions. The adhesion properties of the novel PU adhesive were compared with those of a commercial PU adhesive (CPA). The occurrence and extent of curing reactions and changes in the polymeric network of PA were monitored by Fourier transform infrared spectroscopy (FTIR) and dynamic mechanical analysis. Although the lap shear strength and glass transition temperature of the lignin-based PU adhesives have increased steadily with the NCO/OH ratio ranging from 1.1–2.2, chemical aging resistance can be compromised when the NCO/OH is very low. It was found that the lignin-based PU adhesive with an NCO/OH ratio of 1.3 showed better chemical resistance and adhesion efficiency than CPA possibly because the NCO/OH in the latter is too high as revealed by FTIR spectroscopy. Despite some lower thermal stability and shorter gelation time of lignin-based PU than CPA, the former revealed great potential to reduce the use of petroleum-derived polyols and isocyanates with potential application in the furniture industry as wood bonding adhesive.
Hemp Shives as a Raw Material for the Production of Particleboards
Authors: Auriga Radosław , Pędzik Marta , Mrozowski Robert , Rogoziński Tomasz
Published: December 2022

Increased demand for wood affects its price and thus contributes to the growing interest in raw materials that can be used as a partial or total substitute for wood in the production of particleboard. One of the raw materials for the production of particleboard can be Cannabis sativa or, more precisely, hemp shives. In this work, 7 variants of panels with a density of 650 kg/m3 with 10 and 25% hemp shives substitution in different layers were produced. Particleboards containing hemp shives were characterized by lower density compared to conventional particleboards. The shares of hemp shives at the levels of 10% and 25% have a slight impact on the MOR and MOE; additional IB showed no statistically significant differences between the conventional particleboards and particleboards with a share of hemp shives. For particleboards with 25% hemp shives, a reduction in swelling was observed relative to particleboards made entirely of industrial wood particles.
Self-Powered Gradient Hydrogel Sensor with the Temperature-Triggered Reversible Adhension
Authors: Sun Dong , Peng Cun , Tang Yuan , Qi Pengfei , Fan Wenxin , Xu Qiang , Sui Kunyan
Published: December 2022

The skin, as the largest organ of human body, can use ions as information carriers to convert multiple external stimuli into biological potential signals. So far, artificial skin that can imitate the functionality of human skin has been extensively investigated. However, the demand for additional power, non-reusability and serious damage to the skin greatly limits applications. Here, we have developed a self-powered gradient hydrogel which has high temperature-triggered adhesion and room temperature-triggered easy separation characteristics. The self-powered gradient hydrogels are polymerized using 2-(dimethylamino) ethyl metharcylate (DMAEMA) and N-isopropylacrylamide (NIPAM) under unilateral UV irradiation. The prepared hydrogels achieve good adhesion at high temperature and detachment at a low temperature. In addition, according to the thickness-dependent potential of the gradient hydrogel, the hydrogels can also sense pressure changes. This strategy can inspire the design and manufacture of self-powered gradient hydrogel sensors, contributing to the development of complex intelligent artificial skin sensing systems in the future.
Facile Fabrication of Superhydrophobic and Flame-Retardant Coatings on Cotton Fabrics
Authors: Li Shiwei , Yu Luyan , Xiong Jianhua , Xiong Ying , Bi Shuguang , Quan Heng
Published: December 2022

The hydrophilicity and inherent flammability of cotton textiles severely limit their usage. To solve these drawbacks, a superhydrophobic and flame-retardant (SFR) coating made of chitosan (CH), ammonium polyphosphate (APP), and TiO2-SiO2-HMDS composite was applied to cotton fabric using simple layer-by-layer assembly and dip-coating procedures. First, the fabric was alternately immersed in CH and APP water dispersions, and then immersed in TiO2-SiO2-HMDS composite to form a CH/APP@TiO2-SiO2-HMDS coating on the cotton fabric surface. SEM, EDS, and FTIR were used to analyze the surface morphology, element composition, and functional groups of the cotton fabric, respectively. Vertical burning tests, microscale combustion calorimeter tests, and thermogravimetric analyses were used to evaluate the flammability, combustion behavior, thermal degradation characteristics, and flame-retardant mechanism of this system. When compared to the pristine cotton sample, the deposition of CH and APP enhanced the flame retardancy, residual char, heat release rate, and total heat release of the cotton textiles. The superhydrophobic test results showed that the maximal contact angle of SFR cotton fabric was 153.7°, and possessed excellent superhydrophobicity. Meanwhile, the superhydrophobicity is not lost after 10 laundering cycles or 50 friction cycles. In addition, the UPF value of CH/APP@TiO2-SiO2-HMDS cotton was 825.81, demonstrating excellent UV-shielding properties. Such a durable SFR fabric with a facile fabrication process exhibits potential applications for both oil/water separation and flame retardancy.
Antibacterial Activity and Biocompatibility with the Concentration of Ginger Fraction in Biodegradable Gelatin Methacryloyl (GelMA) Hydrogel Coating for Medical Implants
Authors: Kim Seo-young , Choi Ae-jin , Park Jung-Eun , Jang Yong-seok , Lee Min-ho
Published: December 2022

The gingerols and shogaols derived from ginger have excellent antibacterial properties against oral bacteria. However, some researchers have noted their dose-dependent potential toxicity. The aim of this study was to enhance the biofunctionality and biocompatibility of the application of ginger to dental titanium screws. To increase the amount of coating of the n-hexane-fractionated ginger on the titanium surface and to control its release, ginger was loaded in different concentrations in a photo-crosslinkable GelMA hydrogel. To improve coating stability of the ginger hydrogel (GH), the wettability of the surface was modified by pre-calcification (TNC), then GH was applied on the surface. As a result, the ginger fraction, with a high content of phenolic compounds, was effective in the inhibition of the growth of S. mutans and P. gingivalis. The GH slowly released the main compounds of ginger and showed excellent antibacterial effects with the concentration. Although bone regeneration was slightly reduced with the ginger-loading concentration due to the increased contents of polyphenolic compounds, it was strongly supplemented through the promotion of osteosis formation by the hydrogel and TNC coating. Finally, we proved the biosafety and superior biofunctionalities the GH−TNC coating on a Ti implant. However, it is recommended to use an appropriate concentration, because an excessive concentration of ginger may affect the improved biocompatibility in clinical applications.
Reactive Extrusion-Assisted Process to Obtain Starch Hydrogels through Reaction with Organic Acids
Authors: Marim Beatriz Marjorie , Mantovan Janaina , Gil-Giraldo Gina Alejandra , Pereira Jéssica Fernanda , Simões Bruno Matheus , Yamashita Fabio , Mali Suzana
Published: December 2022

A totally green process based on reactive extrusion was used for the production of cassava starch hydrogels through reaction with two organic crosslinking agents, citric (CA) and tartaric (TA) acids. CA and TA were used at different concentrations (0, 2.5, 5.0, 10.0, 15.0, and 20.0%). Degree of substitution (DS) of hydrogels ranged from 0.023 to 0.365. Fourier transform infrared spectroscopy results showed a new band appearing at 1730 cm−1 associated with ester carbonyl groups. X-ray diffraction indicated that reactive extrusion resulted in the disappearance of diffraction peaks of native starch and samples with lower crystallinity indices ranging from 37% (native starch) to 8–11% in starch hydrogels. Morphology analysis showed that the original granular structure of starch was lost and replaced by a rougher and irregular structure. Water holding capacity values of starch hydrogels obtained by reactive extrusion were superior to those of native starch and the control sample (extruded without the crosslinking agents). Hydrogels obtained with the highest CA or TA concentration (20.0%) resulted in the higher DS and swelling capacities, resulting in samples with 870 and 810% of water retention, respectively. Reactive extrusion was effective in obtaining starch hydrogels by reaction with organic acids.
The Role of Starch in Shaping the Rheo-Mechanical Properties of Fat-in-Water Emulsions
Authors: Rezler Ryszard
Published: December 2022

The DMA technique was used to conduct experiments on the rheo-mechanical properties of emulsified bovine fat meat products stabilised with potato starch. Starch gels with starch concentrations corresponding to the concentration of starch in water in the emulsions under analysis were used as control systems. The research showed that the rheo-mechanical properties of starch gels and starch–fat gels result from the conformational changes occurring within the structural elements of their spatial network. In starch gels, segments formed by complex associations of amylose chains are structural elements, whereas in starch–fat gels (emulsions) these are additionally amylose–fat complexes. Changes occurring during progressive retrogradation increase the degree of cross-linking in them. In starch gels, they are conditioned by the starch concentration, whereas in emulsions they are conditioned by the concentration of starch and the presence of fat. The parameters obtained by adjusting the Avrami equation to the data obtained with the DMA method enabled the determination of three forms of organisation of the dispersion structure of starch–fat systems. Each of these forms of structure organisation is conditioned by the concentration of starch in the emulsion system.
Fault Diagnosis Using Dynamic Principal Component Analysis and GA Feature Selection Modeling for Industrial Processes
Authors: Liu Chenpeng , Bai Jianjun , Wu Feng
Published: December 2022

With the continuous expansion of industrial production scale, most of the chemical process variables are nonlinear, multi-modal and dynamic. For some traditional multivariate statistical monitoring and fault diagnosis algorithms, such as principal component analysis (PCA), the premise of its application is that the process data is time-independent. To this end, a dynamic principal component analysis (DPCA) method is proposed. However, since the input matrix of DPCA fault diagnosis needs to add an augmented matrix to the original data matrix, the number of eigenvalues of the augmented matrix is too large and there are many redundant eigenvectors. Therefore, this paper proposes a fault diagnosis and monitoring algorithm combining feature selection and DPCA, which considers the dynamic characteristics of multivariate data and reduces the dimension of the input matrix. At present, the average modeling and diagnostic accuracy of PCA-based fault diagnosis on T2 statistic is 65.49%, and that on Q statistic is 76.78%. The average modeling and diagnostic accuracy of fault diagnosis based on DPCA on T2 statistic is 63.17%, and the average modeling and diagnostic accuracy on Q statistic is 83.65%. Finally, through a TE simulation process, this paper proves that the accuracy is greatly improved when using the method proposed in this paper compared with PCA and DPCA.
Single-Molecule Chemical Reactions Unveiled in Molecular Junctions
Authors: Bunker Ian , Ayinla Ridwan Tobi , Wang Kun
Published: December 2022

Understanding chemical processes at the single-molecule scale represents the ultimate limit of analytical chemistry. Single-molecule detection techniques allow one to reveal the detailed dynamics and kinetics of a chemical reaction with unprecedented accuracy. It has also enabled the discoveries of new reaction pathways or intermediates/transition states that are inaccessible in conventional ensemble experiments, which is critical to elucidating their intrinsic mechanisms. Thanks to the rapid development of single-molecule junction (SMJ) techniques, detecting chemical reactions via monitoring the electrical current through single molecules has received an increasing amount of attention and has witnessed tremendous advances in recent years. Research efforts in this direction have opened a new route for probing chemical and physical processes with single-molecule precision. This review presents detailed advancements in probing single-molecule chemical reactions using SMJ techniques. We specifically highlight recent progress in investigating electric-field-driven reactions, reaction dynamics and kinetics, host–guest interactions, and redox reactions of different molecular systems. Finally, we discuss the potential of single-molecule detection using SMJs across various future applications.