bluuebunny/crossref_metadata_2025_split huggingface dataset:
Rational and semi‐rational solutions for a (3 + 1)‐dimensional generalized KP–Boussinesq equation in shallow water wave
Authors: Li Lingfei , Yan Yongsheng , Xie Yingying 
Published: July 2022

In this paper, a new extended (3 + 1)‐dimensional generalized Kadomtsev–Petviashvili (KP)–Boussinesq equation, with two additional terms
and
, is proposed and investigated. This new equation models both left and right going waves like the Boussinesq equation and describes the transmission of tsunami waves at the bottom of the ocean and nonlinear ion‐acoustic waves in the magnetized dusty plasm. We have constructed one set of breathers and first order periodic waves from the two‐soliton solution. Moreover, the four‐soliton solution consists of two sets of breathers, second order periodic waves, and a hybrid of breathers and periodic line waves. Then, we introduce two kinds of “long wave” limits to obtain the rational and semi‐rational solutions for
. Under specific parametric constraints, the obtained rational and semi‐rational solutions are nonsingular. The rational solution can be classified as first order line rogue wave, single breather, second order line rogue wave, double breather, a hybrid of breather and line rogue wave, a hybrid of breather, and single soliton. The semi‐rational solution can be classified as the first and second order kink‐shaped rogue wave, a hybrid of breather and one (two) soliton(s), a hybrid of a set of breathers, and a single soliton (breather). In addition, we give Theorem 2.1 for the higher order rational solutions.
Thickening behavior of thermo‐associative water soluble multiblock copolymers under redox RAFT polymerization
Authors: Maldonado‐Textle Hortensia , Jiménez‐Regalado Enrique Javier , St Thomas Claude 
Published: July 2022

AbstractIn this study, the synthesis of thermo‐associative water soluble multiblock copolymers is reported. A trithiocarbonate functionalized polyacrylamide (PAM) was prepared and subsequently utilized in the preparation of three series of thermo‐associative copolymers by addition of N‐isopropylacrylamide (NIPAM) and acrylamide (AM) until reaching a nonablock copolymer with four thermo‐associative blocks distributed into the backbone of polymer. Reactions were performed at 25 °C using a tertbutyl hydroperoxyde (TBHP) and ascorbic acid (As.Ac.) as redox initiator, and S,S′‐Bis (α,α’‐dimethyl‐α”‐acetic acid)‐trithiocarbonate (DMAT) as chain transfer agent. The targeted molecular weight (MnTheo) of PAM was maintained constant (10,000 g/mol) while the expected Mntheo of polyN‐isopropylacrylamide (PNIPAM) was varied from 10,000, 15,000, and 20,000 g/mol, respectively. The synthesized copolymers were characterized by infrared (IR), nuclear magnetic resonance (NMR), size exclusion chromatography (SEC) for determining the structure of materials, whereas ultraviolet (UV) analysis allowed to get access to the cloud point temperature (Tcp) of polymers. Rheological analyses were carried out for examining the effect of thermo‐responsive block on the thickening behavior of aqueous polymer solutions. These analyses were performed at different concentration from 1 to 20 wt. % varying the temperature of measurements from 25, 30, 40, 50, 60, and 70 °C. Results confirmed the influence of the size of thermo‐responsive blocks on the viscosity of these copolymers.
Long‐bonding and effects of carbon hybridization on the bonding of MNgC compounds (M = Cu, Ag, Au)
Authors: Xiong Ke Quan , Li An Yong 
Published: July 2022

AbstractLong bonding is a typical bonding feature in noble gas insertion compounds. It has been shown that in the compounds FNgF and HNgX there exists 3c4e long bonding. In this work, we investigate long bonding in the MNgC type of noble gas insertion compounds with M = Cu/Ag/Au and Ng = Ar/Kr/Xe/Rn. The effect of C hybridization on bonding was also studied by the compounds MNgCCH, MNgC2H3, and MNgC2H5. The structures of these compounds were calculated using MPW1B95, B3LYP‐D3, MP2, and DSD‐BLYP‐D3 methods. It was found that there was indeed long bonding between M and C in the MNgC part of these compounds, which is characterized by three Lewis resonance structures, two ω‐bonded and one σ‐bonded structures. Different C hybridization has obvious influence on the length and strength of the MNg and NgC bonds and also on the long bonding. With the increase of p component in the C spn hybrid the bond lengths increase significantly and the bonds weaken in the MNgC part. However, bonding nature of the MNg and NgC bonds characterized by electron density topological properties are not sensitive to C hybridization, but more sensitive to different metals.
Spin Polarized Electronic Transport and Photocurrent in Chiral Methionine Molecule via Magnetic Tunnel Junction Model from First Principles
Authors: Xu Yingdan , Han Xuefei , Xiao Yin , Wang Yong , Mi Wenbo 
Published: July 2022

AbstractThe spin‐dependent transport properties through chiral amino acids and their modulations by light and magnetic field are important for understanding the intrinsic magnetism and photomagnetic coupling of chiral molecules. Here, the spin‐dependent electronic transport through chiral methionine (R,S‐MET) molecules is studied by theoretical calculations through a magnetic tunnel junction (MTJ) model. R‐MET molecule outputs fully spin polarized photocurrents with different spin channels, while S‐MET is insensitive under polarized light, revealing the spin polarized photocurrent selectivity of chiral molecules. Photocurrent increases greatly in Fe4N/S‐MET/Au MTJ, where S‐MET shows unidirectional spin filtering effect. Fully spin polarized photocurrent appears in Fe4N/R,S‐MET/Au MTJs, whose spin channel can be switched by adjusting magnetization directions. Particularly, chiral‐induced spin selectivity effect appears in Fe4N/R,S‐MET/Au MTJs under specific polarized light and magnetization direction. Understanding the spin‐dependent electronic transport of chiral amino acids can provide a theoretical foundation for life science and bioelectronic devices.
How COVID‐19 pandemic, global risk factors, and oil prices affect Islamic bonds (Sukuk) prices? New insights from time‐frequency analysis
Authors: Naifar Nader , Tiwari Aviral Kumar , Alhashim Mohammed 
Published: July 2022

AbstractThis paper studies the time–frequency co‐movement among Islamic bond (Sukuk) prices, the recent spread of COVID‐19, oil prices, economic policy uncertainty, global financial uncertainty, and global financial distress. The Dow Jones Sukuk Index (hereafter DJSI) is used as a proxy of the global Sukuk market. The Malaysian Sovereign Sukuk index is also used for comparison purposes because Malaysia maintains a leading position as the strongest global player in Islamic finance. The effect of global risk and uncertainty factors on Sukuk prices is controlled for using partial wavelet coherency. The empirical results indicate that the co‐movements between the Sukuk prices (both global and Malaysian Sukuk) and global economic and financial risk factors are time and frequency varying. We also find that global and Malaysian Sukuk markets behave differently with global risk factors throughout the COVID‐19 pandemic period. Furthermore, we find that the co‐movement between Sukuk prices (both global and Malaysian Sukuk) and COVID‐19‐infected cases is stronger only in the short term.
Morphological traits related to potential invasiveness of two subspecies of the crayfish Faxonius neglectus
Authors: Magoulick Daniel D. , Wynne K. Carter , Clark Jessica 
Published: July 2022

AbstractBiological invasions have major environmental and economic impacts, and pose a serious threat to global biodiversity. Invasive crayfish species are one of the greatest threats to native crayfish biodiversity. Additionally, almost 50% of US and Canadian species are considered at risk, making crayfish one of the most imperiled taxonomic groups in the world. Small‐scale (extralimital) invasions are often overlooked and may be more common than large‐scale (extraregional) invasions. One example of an extraregional and extralimital invader is the Ringed Crayfish (Faxonius neglectus), which has been independently introduced multiple times to drainages throughout the United States, including those adjacent to its native range. Traits related to invasiveness, such as chelae size, are suggested to differ between invasive crayfish from extralimital and extraregional source populations with larger size related to increased invasiveness. We examined morphological traits related to invasion potential for both subspecies of F. neglectus, F. neglectus neglectus and F. neglectus chaenodactylus. We sampled 28 stream sites within the known native range of F. neglectus, including the Neosho and Upper White River drainages in Oklahoma, Arkansas and Missouri. Total carapace length, chelae length and chelae width of 30 adult male F. neglectus were measured from each site. We found significant differences in crayfish morphological characteristics among stream sites. We found significantly greater chelae length:carapace length (ChL:CarL) and chelae width:chelae length (ChW:ChL) in F. neglectus chaenodactylus than F. neglectus neglectus. Even among F. neglectus neglectus populations, there were significant differences in ChL:CarL and ChW:ChL. Morphological characteristics suggest that F. neglectus chaenodactylus and some populations of F. neglectus neglectus may be pre‐adapted to the role of invader.
Talking through the “messy middle” of partnerships in science education
Authors: Cheuk Tina , Morales‐Doyle Daniel 
Published: July 2022

AbstractThis paper's focus is on the “middle” of partnerships for equity in science education. Middle is used in a temporal sense, meaning the time after the general purposes and terms of working together have been set and before outcomes have been achieved. The middle of the partnership also represents people interacting, bounded around the edges, by their institutional roles, norms, resources, and priorities. As co‐authors who had not previously collaborated (or even met in person), we approached the construction of this manuscript as a dialogue where we learn by sharing narrations of experiences and values and principles. We were inspired by the conversational book between Horton and Freire (1990) and specifically their discussion of “Is it possible to just teach biology?” (p. 102). In our conversation, we illustrate the ways in which partnerships may make justice‐oriented science education possible. Our focus is on complementary and contradictory knowledges, and ways of knowing, institutional resources and constraints, and strategies for making transformative change. We explore the middle of partnerships as a series of opportunities for learning and growing, caring for one another, and building solidarity spaces together.
Effect of Adding Conditions of Polyvinyl Alcohol on the Reaction Behavior and Particle Characteristics of Spherical Phenol‐formaldehyde Resin Beads
Authors: Lee Ya‐Shiuan , Chen Yi‐Chun , Lee Wen‐Jau 
Published: July 2022

AbstractPhenol‐formaldehyde resin (PF) is the oldest synthetic resin. Through the design of synthesis conditions, PF resins with different characteristics can be provided, which are widely used in molding materials, adhesives and impregnation. Spherical PF beads are a hardened resin prepared by a special synthesis method. In this study, a mixture of phenol and formaldehyde was added with triethylamine, polyvinyl alcohol (PVA), and hexamethylenetetramine as a catalyst, granulating agent, and hardening agent, respectively. Spherical PF beads were prepared by a three‐stage suspension polymerization in a large‐scale water system, and the effects of PVA addition conditions on the reaction behavior and particle characteristics were discussed. The results show that formalin with a concentration of 14 % can be used as a formaldehyde raw material to prepare spherical PF beads by suspension polymerization. The largest spherical PF beads can be obtained with a reactant‐liquid ratio of 2/1, a stirring speed of 300 rpm, and an addition amount of BF‐04 of 2 %. The particle size of 14–20 mesh accounts for 83.9 % and has the average particle size of 1016 μm.
Hierarchical Nitrogen‐Enriched Carbon from Rationally Designed Polyimide Precursor for Exceptional Acetone Adsorption
Authors: Sheng Peng , Liu Baogen , Ren Yadong , Zeng Zheng , Li Liqing 
Published: July 2022

AbstractThe adsorption capacity of porous adsorbent to volatile organic compounds (VOCs) is restricted by pore size distribution and surface functionalities. In this study, we report an effective N‐doped porous carbon synthesis strategy using rationally designed polyimide as precursor and subsequently copper chloride (CuCl2) mild activation. Specifically, by carefully changing the thiourea/urea ratio, polyimide precursors of different configurations can be designed and synthesized, which not only facilitates the transformation to a mesoporous structure, but also slightly enriches the surface heteroatoms. These unique properties result in a series of hierarchical porous carbon with high surface area (2045 m2/g), large mesopore volume (1.32 cm3/g) and rich nitrogen content (8.95 at %). Such carbon consequently shows exceptional static acetone adsorption performance of 768 mg/g (25 °C) and 799 mg/g (15 °C) and fast dynamic transfer rate. The abundant mesoporous structure provides the necessary diffusion channels to shorten the transmission distance and transmission resistance of acetone molecules, thereby contributing to this high acetone adsorption performance. Moreover, electrostatic potential (ESP) charge analysis shows that the doping of nitrogen atoms can significantly change the charge distribution on the sample surface, and enhance the affinity with acetone molecules through electrostatic interaction and Lewis acid‐base interaction
A Green Methodology for the Synthesis of Some Regioselective 1, 4‐Disubstituted 1,2,3‐Triazoles via Laccase‐Mediated Click Reaction.
Authors: Gupta Swati , Singh Ashmita , Narula Anudeep K. 
Published: July 2022

AbstractA novel green efficient methodology was developed for the synthesis of some regioselective 1,4‐disubstituted‐1,2,3‐triazoles through an enzyme laccase (Trametes Versicolor) catalyzed reaction. The reaction utilizes the Click chemistry approach for the formation of highly substituted and regioselective triazoles. The methodology is unprecedented in the way that it executes under mild conditions at room temperature using green buffer solvents. An array of substituted triazoles were feasibly synthesized and characterized via spectroscopic techniques.
Electric Field Polarized Fe−N Functionalized Graphene Oxide Nanosheet Catalyst for Efficient Oxygen Reduction Reaction
Authors: Zhao Rong , Xia Jiaxin , Adamaquaye Peter , Zhao Guang‐lin 
Published: July 2022

AbstractLow‐cost noble‐metal‐free electrocatalysts for oxygen reduction reaction (ORR) are useful for future energy storage and conversion devices, and other technologies. In this work, iron (Fe)‐nitrogen (N) functionalized graphene oxide (Fe−N−GO) nanosheets have been synthesized and studied for ORR properties in alkaline solution. We utilized a multi‐layer/multi‐polarization method to study the DC electric field polarization effect on the electrocatalytic properties of the Fe−N−GO catalyst. The poling effect with DC electric field was created on the catalyst ink drop‐casted on a polished glassy carbon working electrode, resulting in more compact electrocatalyst electrode. Compared to the commercial Pt/C catalyst, the polarized Fe−N−GO catalyst exhibited similar ORR catalytic activity along with superior stability in alkaline media.
Ed .A Novel Strategy to Arrest Bacterial Pathogen Infestation Using Poly(o‐Phenylenediamine)/ Montmorillonite Nanocomposites
Authors: Verma Anurakshee , Parveen Romana , Shamsi Tooba Naz , Khan Azmat Ali , Fatima Sadaf , Aazam Elham S. , Riaz Ufana 
Published: July 2022

AbstractIntercalation and in‐situ polymerization of POPD within MMT was successfully accomplished using sonochemical technique. Montmorillonite/poly(o‐phenylenediamine) (MMT/POPD) nanocomposites (NCs) were checked for their antimicrobial activity against four bacterial strains. The antibacterial activity of MMT/POPD NCs was investigated against E. coli, S. aureus, P. aeruginosa and B. subtilisby broth micro‐dilution and agar well diffusion methods. Furthermore, the effective concentration (EC50) and minimum inhibitory concentration (MIC) of the NCs were also determined. Results clearly showed that the NCs had viable cell reduction capability and could act as potential antibacterial agents.
Nickel‐Catalyzed Thiocarbonylation of Aryl Iodides with Dialkyl Disulfides for the Synthesis of Thioesters
Authors: Xiao Yong‐Mei , Lv Wen‐Wen , Yuan Jin‐Wei , Yang Liang‐Ru , Mao Pu , Mai Wen‐Peng 
Published: July 2022

AbstractA nickel‐catalyzed molybdenum‐promoted carbonylative synthesis of thioesters between aryl iodides and dialkyl disulfides has been developed. This method provides a novel and practical route to aryl thioesters under CO‐gas‐free conditions. Using Mo(CO)6 as a solid CO source, many thioesters were obtained in moderate yields without expensive metals such as palladium.
Novel Fluorescent Polyurethane Coating on Fabric with Acid‐Base Indicating Function in Solution
Authors: Shu Yihu , Gao Jian , Wang Chaoxia , Yin Yunjie 
Published: July 2022

AbstractThe preparation of multifunctional composite materials with maximum fluorescence emission is an ideal choice to replace fluorescent dyes. We synthesized a series of novel fluorescence polyurethane (FPU) films. The effect of different contents, different solvents and different pH on the fluorescence intensity were investigated in detail. In accordance with increasing proportion of 2, 7‐Dichlorofluoresce (DCF) in the FPU, the emission peak exhibit a gradual bathochromic shift and the fluorescence intensity show a trend of increasing first and then decreasing. The strong fluorescence emission of the obtained fluorescent film is in the range of about 570 nm. The maximum fluorescence intensity is 842, and the reflectance of the film is 21 % with a bright yellow at this time. In addition, acid‐base response fluorescence emission performance are endowed the fluorescent polyurethane film in the solution state. Different luminous intensities are emit by the film solution samples in near neutral (540 nm, yellow‐green light) and alkali (580 nm, orange‐yellow light). The maximum displacement exceeds 40 nm. Compared near neutral (pH=7) to alkaline (pH=12) environmental, the fluorescence emission intensity is increased by 1800 % (from 90 increasing to 1680). By establishing the relationship between the concentration and the fluorescence emission intensity, the fluorescence intensity can be clearly known through the color difference, and the concentration of 0.25 % is selected for doping to achieve the balance between the emission intensity and the color of the fluorescent substance. We use hot‐pressing to finish the fluorescent polyurethane (FPU) film on the surface of the fabric at a lower temperature (Compared with high temperature and high pressure dyeing method). There is a potential application prospects for our fluorescent polyurethane films in chemical sensing, biological imaging, anti‐counterfeiting technology, and smart light‐emitting fabrics.
Preparation of Polypyrrole/Boron Nitride Composites and Composite Sponges for Efficient Photothermal Utilization
Authors: Ma Chunxue , He Lili , Liu Rui , Guan Hongyu , Ge Chunhua , Zhang Xiangdong 
Published: July 2022

AbstractPhotothermal materials can improve the photothermal conversion efficiency. Here, we design and prepare a photothermal material which has both high light harvesting ability and high thermal conductivity for efficient utilization of light energy. Polypyrrole (PPy) was polymerized in the surface of boron nitride (h‐BN) to form polypyrrole/boron nitride (h‐BN/PPy) composites. The h‐BN/PPy composites can be dispersed in glycol‐water solution to form nanofluids with photothermal conversion properties. To further expand the field of h‐BN/PPy systems. By loading h‐BN and PPy on melamine sponge, MF/h‐BN/PPy composite sponges (MFBP) with high hydrophobicity was creatively obtained. The composite sponges can float on the surface of simulated seawater and has rich porous structure, which is conducive to the escape of water vapor. The evaporation rate of simulated seawater reached 1.21 kg m−2 h−1. Such a composite with simple preparation process and low energy consumption but high photothermal conversion efficiency has promise in photothermal conversion.
Selective N‐Monovinylation of Primary Aromatic Amides Using Calcium Carbide as an Alkyne Source
Authors: Zhang Zeshuai , Wen Fei , Liu Haiyan , Li Zheng 
Published: July 2022

AbstractAn efficient method for the selective N‐monovinylation of primary aromatic amides using calcium carbide as an alkyne source is described. A series of N‐vinylbenzamides (enamides) were readily synthesized by this strategy. The salient features for this protocol are the use of inexpensive, easy‐to‐handle solid alkyne source, high chemoselectivity, transition metal catalyst‐free, good functional group tolerance, and simple work‐up procedures. These reactions can also be extended to the gram‐scale level.
Porous Ni−Al−O Fabricated by a Facile Hydrothermal Method: Improved Catalytic Performance for the Oxidative Dehydrogenation of Ethane to Produce Ethylene
Authors: Li Dong , Kong Lian , Fan Xiaoqiang , Xie Zean , Xiao Xia , Zhao Zhen 
Published: July 2022

AbstractThe oxidative dehydrogenation of ethane (ODHE) to ethylene is a process with many advantages (such as energy conservation and coke resistance). Herein, flower‐like Ni−Al−O catalysts with hierarchical structure and high surface areas were fabricated through a hydrothermal route and were applied to ODHE using O2 as oxidant. Compared with NiO alone, the Al3+ insertion into NiO matrix not only increases the C2H4 selectivity by 3–4 times, but also prevents the generation of CO2 and CH4 above 500 °C. At 550 °C, all Ni−Al−O catalysts maintain approximately 50 % ethylene selectivity regardless of Al content. The ethylene yield of 29.5 % with C2H4 selectivity 55.7 % over Ni−Al0.8‐O sample can be reached at 500 °C. Moreover, the Ni−Al0.8‐O catalyst presents a good stability and has no loss of activity after 100 h continuous evaluation. The various characterizations were carried out for investigating the nature of as‐prepared Ni−Al−O catalysts with different Al loadings. Experimental results demonstrate that the addition of Al not only affects the structure and texture properties of NiO, but also impacts the reducibility of Ni species and the amount of active oxygen species. It is found that the Al3+ substitution results in: (1) smaller NiO size; (2) larger specific surface area; (3) weaker reducibility and (4) fewer non‐stoichiometric oxygen species. Therefore, the significant improvement of ethylene selectivity is observed in Ni−Alx‐O catalysts.
Novel Cobalt‐Supported Silica‐Coated Ferrite Nanoparticles Applicable for Acylation of Amine, Phenol, and Thiols Derivatives under Solvent‐Free Condition
Authors: Patil Shripad M. , Ingale Ajit P. , Pise Ashok S. , Bhondave Rahul S. 
Published: July 2022

AbstractThe straightforward co‐precipitation approach was used to effectively manufacture novel silica‐coated magnetic nanoparticles doped with cobalt (Co3O4). These nanoparticles were characterized using Field Emission Scanning Electron Microscopy (FE‐SEM), Energy‐Dispersive X‐ray Spectroscopy (EDS), Wavelength‐Dispersive Spectroscopy (WDX), Powder X‐ray Diffraction Spectroscopy (PXRD), Fourier transform infrared spectroscopy (FT‐IR), Thermo‐gravimetric Analysis (TGA), Inductive coupled plasma‐optical emission spectrometry (ICP‐OES), and Transmission Electron Microscopy (TEM), etc. Intriguingly, the catalytic performance of these nanocrystals for the amines, phenols, alcohols, and thiols acylation processes was examined in solvent‐free conditions, with outstanding yields. These nanoparticles were recycled at least 12 times without losing their catalytic activity.