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The developing interest in thermal engineering and nano-technology presented the idea of nanoparticles with enhanced thermal mechanisms and attained convinced novel applications in heat transportation systems, solar energy, micromechanics, air conditioning systems, cooling and heating facilities, bio-medical applications like cancer treatment, artificial heart surgery etc. Beside this, the phenomenon of entropy generation is another fascinating research area which used to improve the assessment of heat transportation with optimized procedure. The entropy generation in bio-convective flow of Eyring-Powell nanofluid over permeable stretched surface of cylinder is scrutinized in this research. The effects of magnetic field, thermal radiation and viscous dissipation are considered. Concentration communication is obtained in view of activation energy associated with binary chemical reaction. Furthermore, properties of Brownian diffusion and thermophoresis of nanoparticles are accounted. Suspended nanoparticles are made stable through mutual effects of bioconvection and buoyancy forces. Total entropy generation rate is modeled through second thermodynamics law. The governing flow model is obtained with the help of boundary layer approximations. Dimensional model is transformed into non-dimensional one by transformations and then tackled by Newton built-in shooting procedure. Impact of different influential variables on entropy generation, velocity, temperature, concentration, Bejan number and motile density of microorganisms are analyzed via graphs. Numerical values of skin friction coefficient, density, Sherwood and Nusselt numbers are tabulated and examined. Major findings are listed at the end. Since this analysis is based on theoretical flow assumptions, therefore the flow parameters specify the constant range like 0.0 ⩽ Γ ⩽ 6.0 , 1.0 ⩽ γ ⩽ 4.0 , 0.1 ⩽ H a ⩽ 1.2 , 0.2 ⩽ λ ⩽ 0.6 , 0.2 ⩽ R d ⩽ 1.7 , 0.1 ⩽ K ⩽ 3.0 , 0.1 ⩽ Pr ⩽ 4.5 , 0.3 ⩽ N b ⩽ 1.8 , 0.2 ⩽ N t ⩽ 1.7 , 0.0 ⩽ E 1 ⩽ 1.0 , 1.0 ⩽ E c ⩽ 4.0 , 0.2 ⩽ σ ⩽ 1.4 , 0.4 ⩽ S c ⩽ 1.7 , 1.0 ⩽ δ ⩽ 2.5 , 0.5 ⩽ P e ⩽ 2.0 , 0.5 ⩽ Ω ° ⩽ 2.0 , 0.1 ⩽ B r ⩽ 1.0 , 0.1 ⩽ L b ⩽ 1.5 . The results show that fluid velocity decreases with curvature parameter and porosity constant. A decreasing variation in nanofluid temperature due to curvature parameter is examined. The entropy generation and Bejan number decline Brinkman number, motile density diffusion parameter and mass concentration diffusion variable. Furthermore, it is observed that skin friction coefficient increases with curvature parameter and porosity constant.

Hypothesis Organic radical polymers with tailored pendant functionalities have emerged as exciting and promising materials for their application versatility. Moreover, eco-friendly polymer-based organic nanomaterials with redox-active pendant side groups can replace the harmful heavy metal-based inorganic materials. On the other hand, self-assembled nanomaterials are of great interest and attracted more attention recently for their promising application in different advanced fields, but it is yet challenging to predict suitable hydrophilic-lipophilic balance (HLB) for stimuli-responsive random copolymers assembly due to structural irregularity. Among several experimental techniques, electron paramagnetic resonance (EPR) spectroscopy plays a unique and promising role in revealing structural and dynamic information of nanostructured radical containing materials. Experiments In this study, a series of spin labeled amphiphilic random copolymers poly(methyl methacrylate-co-acrylic acid) have been synthesized and characterized by FT-IR, UV–Vis spectroscopies, TGA, DSC and water contact angle (CA) techniques. Their electrochemical properties have been determined by cyclic voltammetry (CV) in different organic solvents. EPR spectroscopy has been applied with other analytical techniques to elucidate the smart supramolecular nanoparticles (SNPs) formation, stimuli-responsiveness and structural changes through the dynamics of different molecular interactions. Findings The structural and dynamic information of self-assembled nanoparticles have been observed to be dependent on multiple-stimuli-responsiveness in different microenvironments by applying physiological and chemical parameters such as the different concentration of radicals, pH, temperature, nature of the solvent and reducing agent. The obtained results reveal the knowledge to understand insight into the mechanism for the formation of stimuli-responsive colloidal nanoparticles assembled from amphiphilic random copolymers with apt HLB value. The CV results reveal that the charge transfer process of the nanoparticles in solution was diffusion regulated and depended on the accessibility of radicals. The radical (spin labeled) polymers offer a broad way to develop stimuli-responsive materials in various colloidal nanostructures by changing the microenvironment, appreciating their potential advanced applications in electronic devices, catalysis, stimuli-triggered drug/gene delivery and reactive oxygen species (ROS) scavenger.

Here flow behavior of stratified Williamson nanofluid over porous surface of stretching cylinder is examined. The concept of gyrotactic miscroorganisms is implemented to control the random movement of suspended nanoparticles. Effects of magnetic field is accounted. Further chemical reaction with Arrhenius activation energy is considered for the modeling of concentration equation. Brownian motion and thermophoresis effects are further considered. The flow model is obtained by employing the boundary layer assumptions. Appropriate transformations are used to reduced the dimensional system into non-dimensional ones. NDSolve code in MATHEMATICA software is used to tackle the obtained non-dimensional flow expressions. Behavior of velocity, mass concentration, temperature and motile microorganisms versus involved variables is examined graphically. The engineering curiosity like skin friction coefficient, heat and mass transfer rates (Nusselt and Sherwood numbers) and density number are computed and analyzed. Important observations are highlighted at the end.

Textile and printing industries play a vital role in the economy of any country. But the effluents of these industries, which contain toxic Methylene Blue (MB) dye when mixed with fresh water, make it unfit for human health and aquatic life. For the removal of MB, different adsorbents were used, but they were expensive, non-biodegradable or less effective. In this research, novel carboxymethyl starch grafted poly 2-carboxyethyl acrylate (CM-St-g-P2CEtA) was synthesized by reacting carboxymethyl starch with 2-carboxyethyl acrylate. The reaction followed a free radical polymerization mechanism. The structure and properties of CM-St-g-P2CEtA were investigated by advanced analytical techniques. The CM-St-g-P2CEtA was employed for the remediation of Methylene Blue (MB) dye from wastewater. The removal percentage (%R) of MB was checked under different parameters, like different pH levels, different initial concentrations of dye, different adsorbent doses, and different contact times. The results obtained during the experiment were subjected to different adsorption and kinetic models. In the kinetic investigation, the experimental results were best represented by the pseudo-second-order kinetic model due to its high R

Herein, poly(2-(methacryloyloxy) ethyl ferrocene carboxylate-co-(methacrylohydroxyhexane azobenzene)s) (P(FHEMA-co-MAZOHE)s) were prepared by random copolymerization and were characterized by proton nuclear magnetic resonance (1H NMR) and gel permeation chromatography (GPC) to confirm the structures and molecular weights respectively. Thermal variations were analyzed by thermogravimetric (TG), differential thermogravimetric (DTG) and differential scanning calorimetry (DSC) techniques. Finally, redox and photo stimuli-responsive properties were confirmed by cyclic voltammetry (CV) and ultraviolet–visible spectroscopy (UV–vis) respectively. The results revealed that (P(FHEMA-co-MAZOHE)s) can be useful as information storage materials.

With the development of society, plastics play a significant role in daily supplies owing to their advantages. Whereas, insufficient scratch resistance and vulnerable plastic surfaces result in the constraint of their range of application fields, for instance, electronic products. Hence, it is a highly desirable objective of researchers to investigate hardening coatings for protecting plastic surfaces, by selecting polyurethane acrylate (PUA) as film-forming materials attributing to their adjustable features. This article reveals components of PUA and principles for its hardening modification, and summaries various methods of hardening modification of PUA-based coatings, such as improving the crosslinking density, strengthening hydrogen bonding, incorporating rigid groups into molecular structure, introducing inorganic nanoparticles into resin matrix and transferring linear PUA into hyperbranched analogs. Moreover, optimal strategies for the preparation of PUA-based hardening films from above five tactics are discussed.

Two-dimensional stagnation point flow of single and multi walls carbon nanotubes towards a stretching sheet is addressed. Induced magnetic field is considered. Homogeneous-heterogeneous reactions is accounted. Both SWCNTs (single wall) and MWCNTs (multi wall) are considered as nanoparticles whereas water and kerosene oil are considered as base liquid. Xue’s model is used for the physical characteristics of density, specific heat and thermal conductivity. The consequences of present work is to investigate impact of induced magnetic field in quartic chemical reactive stagnation point flow with influence of SWCNTs (single wall) and MWCNTs (multi wall). Dimensionless variables are introduced to model physical problem mathematically. Equations are then solved numerically with the help of Built-in-Shooting technique for non-dimensional induced magnetic field, velocity, concentration and temperature. The impacts of different dimensionless flow variables like stretching rate ratio parameter, magnetic parameter, thermal radiation, reciprocal magnetic Prandtl number, homogeneous reaction and heterogeneous reactions parameters and heat generation parameter are depicted through graphs. Computational analysis for surface drag force and Nusselt number are tabulated to examine the behaviors at stretched sheet. It is noticed that induced magnetic field enhances via higher nanoparticles volumetric fraction. Furthermore, multi (MWCNTs) has more contribution in enhancing induced magnetic field when compared with single (SWCNTs).

Xanthomonas oryzae pv. oryzae (Xoo), the causal agent of bacterial leaf blight in rice, delivers transcription activator-like effector (TALE) proteins into host cells to activate susceptibility or resistance (R) genes that promote disease or immunity, respectively. Nonhost plants serve as potential reservoirs of R genes; consequently, nonhost R genes may trap TALEs to trigger an immune response. In this study, we screened 17 Xoo TALEs for their ability to induce a hypersensitive response (HR) in the nonhost plant Nicotiana benthamiana (Nb); only AvrXa10 elicited an HR when transiently expressed in Nb. The HR generated by AvrXa10 required both the central repeat region and the activation domain, suggesting a specific interaction between AvrXa10 and a potential R-like gene in nonhost plants. Evans blue staining and ion leakage measurements confirmed that the AvrXa10-triggered HR was a form of cell death, and the transient expression of AvrXa10 in Nb induced immune responses. Genes targeted by AvrXa10 in the Nb genome were identified by transcriptome profiling and prediction of effector binding sites. Using several approaches (in vivo reporter assays, electrophoretic mobility-shift assays, targeted designer TALEs, and on-spot gene silencing), we confirmed that AvrXa10 targets NbZnFP1, a C2H2-type zinc finger protein that resides in the nucleus. Functional analysis indicated that overexpression of NbZnFP1 and its rice orthologs triggered cell death in rice protoplasts. An NbZnFP1 ortholog was also identified in tomato and was specifically activated by AvrXa10. These results demonstrate that NbZnFP1 is a nonhost R gene that traps AvrXa10 to promote plant immunity in Nb., Seventeen Xoo TALEs were screened for their ability to cause a hypersensitive response (HR) in N. benthamiana (Nb), and only AvrXa10 elicited a stable HR in Nb. AvrXa10 was shown to activate NbZnFP1, a C2H2-type zinc finger protein, which led to HR in Nb. These results demonstrate that TALE proteins can be trapped by R-like genes in nonhost plants to promote immunity.

Metal-organic frameworks (MOFs) have emerged as an attractive class of porous crystalline polymers in recent decade years, which are built from metal nodes and organic linkers with highly regular spatial structures, tunable pores and enormous surface areas. Compared with common bulky MOFs, two-dimension MOFs nanosheets (2D MNS) exhibit outstanding properties like ultrathin thickness and more accessible active sits are considered as a compelling two-dimension material now. Here various methods to obtain MNS including “top-down” and “bottom-up” will be introduced and their applications in separation, catalysis and sensors will also be discussed in this review.

Microneedle technology relates to pharmacy, polymer chemistry and micromachining. Microneedle can effectively deliver insulin into systemic circulation across the skin. This process does not affect the activity of insulin. Compared to subcutaneous injection, microneedles cause less pain for their special structure. This review thoroughly discusses the preparation technologies of the microneedles-based insulin delivery system including solid, hollow, dissolving, phase transition, glucose-responsive microneedle patches. In the meantime, the properties, challenges and clinical/commercial status of the microneedles-based insulin delivery system are also discussed in this review.

The Burning rate of a solid propellant predominantly influences its internal ballistic behavior and it has been well known that incorporation of small quantities of certain classes of organic and inorganic substance to a propellant can drastically alter its burning rate characteristics. The inclusion of energetic materials and burning rate catalysts (BRCs) from the metallocene family (e.g., ferrocene (Fc) and 2,2-bis (ethylferrocenyl) propane also known as catocene (Cat)) has been a promising avenue for efficiently increasing the burning rate of propellants. Fc-based materials are dominantly used as burning rate catalysts in solid propellants because of their low volatility, higher compatibility with organic binders, microscopic homogeneities in distribution, broad range of burning rate adjustments, better ignitability and distinct catalytic features. However, in solid composite propellants, Fc-based polymers and derivatives show undesired properties of high migration, that is travelling out from propellant grain to surrounding insulation material on prolong storage, evaporation or sublimation loss during processing and curing as well as phase separation by crystallization in low-temperature applications, limiting their application as BRCs. This article outlines the latest synthetic advancements in the field of Fc-based BRCs, as well as highlighting their catalytic and anti-migration mechanisms.

The present studies provide qualitative aspects of pine wilt disease model while incorporating convex incidence rate. Studying the nature of the proposed model, it is shown that the basic reproductive number completely determine various dynamics of the model. The global asymptotic stability analysis is expounded at different equilibrium points. The model has shown that the disease disappear, when the threshold quantity falls below unity. Numerical results are presented graphically to illustrate theoretical discussions.

Silver nanowires (AgNWs) have attracted growing interest because of their wide range of applications in modern nano electronic appliances. During polyol method, the presence of cations and anions in the reaction solution has influence on the final morphology of AgNWs. Here we report a feasible way to prepare AgNWs by polyol method. Copper bromide (CuBr2) salt was used to provide anions and cations in the reaction solution. The anions (Br−) helps in reducing the amount of free Ag+ by forming silver bromide (AgBr) during initial silver seeds formation and the cations scavenge oxygen from the surface of AgNWs during preferential growth of the AgNWs. Ethylene glycol (EG) was used as a solvent and reducing agent, silver nitrate (AgNO3) was used as Ag source and polyvinyl pyrrolidone (PVP) was used as a capping agent. The effects of various factors which influence the final morphology of AgNWs were studied. AgNWs were successfully synthesized in the presence of CuBr2 salt. The morphology of the synthesized AgNWs was characterized by the SEM and TEM. The crystallinity was characterized by HRTEM, SAED and XRD. The LSPR peaks of Ag nanostructures were revealed by UV–Vis spectroscopy. The conductive properties of AgNWs thin conductive films were studied by coating the synthesized nanowires on polyethylene terephthalate (PET) substrate.

Recently, metal organic frameworks (MOFs) have attracted tremendous research attention in many fields, including gas separation, wastewater treatment, energy storage and conversion, catalysis, sensors, etc. To satisfy various demands of special practical applications, the pristine MOFs were usually hybridized with other molecules to form multifunctional materials. Due to their unique reversible redox properties, outstanding optical and electrochemical activities, ferrocene (Fc) and its derivatives have been employed as the guest molecules or functional units in MOFs, these Fc-contained MOFs usually exhibit unique performance in many fields compared with pristine MOFs and bare Fc molecules. In this review, the recent progresses of Fc-contained MOFs and their derived materials are reviewed, including the role of Fc in Fc-contained MOFs, synthesis methods and corresponding applications. The challenges and potential research directions of Fc-contained MOFs are also presented and highlighted.

Hybrid nanofluids are novel fluids created by suspending two or more dissimilar nano sized particles in base fluids. Thermal conductivity of hybrid nanofluids is more than nanofluids. Now a day, due to high thermal conductivity and applications in engineering and industry, hybrid nanofluids have become attractive area of research for scientist and researchers. The main objective of current communication is to study the stagnation point flow and heat transfer in viscous hybrid nanofluid towards a stretched cylinder. Flow characteristics are examined under the effect of magnetic field and mixed convention. Furthermore, energy communication is constructed considering thermal radiation, uniform heat source and viscous dissipation. The obtained governing dimensional model is transformed into ordinary ones using suitable transformations. ND-solve code is used to tackle the ordinary differential equations. Results are discussed and compared subject to nanofluid and hybrid nanofluid and plotted graphically. Moreover, Nusselt number and skin friction coefficient are studied numerically. Key outcomes are highlighted at the end.

A theoretical study of entropy generation (EG) has been conducted in flow of second grade nanomaterial in the presence of Darcy Forhheimer porous space. MHD stagnation point flow with nonlinear mixed convection is examined. Joule heating, nonlinear radiation, Brownian diffusion, dissipation and thermophoresis effects are accounted in the modeling of energy expression. Entropy rate is calculated. The chemical reaction is considered for mass transport with activation energy is addressed. The nonlinear flow expressions are analytical tackled for series development via homotopy method. Flow parameters are graphically discussed. Skin friction and Nusselt number are graphically interpreted and discussed. The obtained outcomes addressed that the velocity decreases against magnetic variable. Thermal field and layer thickness growths via radiation and Eckert number. Key observations are listed.

Efficient composite solid propellants possess stable burning rate (BR) and low-pressure exponents. To achieve the ideal performance of propellants, addition of burning rate catalysts (BRC) to the propellants system is one of the best choice. BRC are of tremendous notable significance in composite propellants for their distinctive feature to positively enhance the operational efficiency of solid propellants. In this regard, many valuable kinds of BRC have been synthesized. Due to their better ignitability, ferrocene-based compounds are well-known class of BRC. However, considerable migration and diffusion tendency of this developed class of useful compounds during storage procedures of composite solid propellants limit their practical use as an ideal BRC. This article reviews recent advances in the active field of Fc-based derivatives. In gradual addition, this article also highlights recent progress of Fc-based derivatives as a BRCs and adequately discuss their significant improvements in anti-migration properties.

In this study carboxymethyl starch grafted poly(methacrylic acids) (CMS-g-PMAAs) were synthesized by treating carboxymethyl starch with methacrylic acid in the presence of initiator potassium persulfate (KPS). The modified starches were characterized by proton nuclear magnetic resonance (1H NMR) and fourier-transform infrared (FT-IR) spectroscopy. The crystallinity of the modified starches was analyzed by x-ray diffraction (XRD) while thermal properties of the modified starches were found out by thermogravimetric analysis (TGA) and differential thermal analysis (DTG). These modified starches were then tested as an adsorbent for the removal of ammonia and phenol from the gaseous mixture. The maximum adsorption efficiencies of CMS, CMS-g-PMAA1, CMS-g-PMAA2, and CMS-g-PMAA3 for ammonia were 0.005, 0.020, 0.023 and 0.031 g/g respectively. Similarly, for phenol, the maximum adsorption efficiencies of CMS, CMS-g-PMAA1, CMS-g-PMAA2 and CMS-g-PMAA3 were shown to be 0.2085, 0.2445, 0.2473 and 0.2501 g/g respectively. It was shown that CMS-g-PMAAs could be used as an additive in cigarette filters to remove the toxicant ammonia and phenol from cigarette smoke.

Smoking is one of the major cause of health problems around the globe. The present article deals with the dynamics of giving up smoking model of fractional order. We study analytical solution (approximate solution) of the concerned model with the help of Laplace transformation. The solution of the model will be obtained in form of infinite series which converges rapidly to its exact value. Moreover, we compare our results with the results obtained by Runge-Kutta method. Some plots are presented to show the reliability and simplicity of the method. Keywords: Smoking dynamics, Mathematical models, Fractional derivatives, Laplace-Adomian decomposition method, Analytical solution

Different copolymers (poly(2-(methacryloyloxy) ethyl ferrocene carboxylate-co-methacrylo-4-aminoazobenzene-co-methacrylic acid)s) (P(FHEMA-co-MAZO-co-MAA)s) were synthesized and their different properties were analyzed in this work. Methacrylic acid was introduced as a side group to possibly affect the photostability. The synthesized copolymers were characterized by nuclear magnetic resonance (1H NMR) spectroscopy and gel permeation chromatography (GPC). Thermal studies were performed by thermogravimetric (TG), differential thermogravimetric (DTG) and differential scanning calorimetry (DSC) analysis, which showed that the copolymers were thermally stable under the operating conditions of the information storage devices. Redox studies and photoresponsive studies were performed by CV technique and UV/vis spectroscopy which showed that these copolymers contained good redox and photoresponsive properties. The obtained results paved the way towards the four states information storage of the materials.

Five ferrocene (Fc)-based compounds (HQ-Fcs) were synthesized by the condensation reaction of ferrocenecarbonyl chloride with corresponding hydroquinone derivatives. Nuclear magnetic resonance (1H NMR), and Fourier transform infrared (FT-IR) were used as evidence for the synthesis of HQ-Fcs. The electrochemical properties of HQ-Fcs were investigated by cyclic voltammetry (CV) and suggested that these compounds exhibited redox behavior due to ferrocene groups. The burning rate catalytic effect of HQ-Fcs was examined by Thermogravimetric (TG) and differential Thermogravimetric (DTG) techniques. Thermal analysis results indicated that HQ-Fcs were thermally stable and have better burning rate catalytic effects in accelerating thermal decomposition of AP. Anti-migration behavior of HQ-Fcs in comparison to commonly used 2,2-bis (ethylferrocenyl) propane (catocene) and Fc was evaluated. It was observed that HQ-Fcs delivered excellent anti-migration performances than catocene and Fc.

In this paper a new technique based on quartic non-polynomial spline functions connecting spline functions values at mid knots and their corresponding values of the fourth-order derivatives is developed. This approach leads to a family of numerical methods for computing approximations to the solution of a system of fourth-order boundary-value problems associated with obstacle, unilateral, and contact problems. It is shown that the present family of methods gives better approximations. Existing second and fourth-order finite-difference and spline functions based methods developed at mid knots become special cases of the new approach. Numerical examples are given to illustrate applicability and efficiency of the new methods.