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Abstract In this paper, the quantum effects of fine scaling on the buckling behavior of carbon nanotubes (CNTs) under axial loading are investigated. Molecular mechanics and quantum mechanics are respectively utilized to study the buckling behavior and to obtain the molecular mechanics coefficients of fine-scale nanotubes. The results of buckling behavior of CNTs with different chiralities with finite and infinite dimensions are given, and a comparison study is presented on them. The differences between finite and infinite nanotubes reflect the quantum effects of fine scaling on the buckling behavior. In addition, the results show that the dimensional changes highly affect the mechanical properties and the buckling behavior of CNTs to certain dimensions. Moreover, dimensional changes have a significant effect on the critical buckling strain. Beside, in addition to the structure dimensions, the arrangement of structural and boundary atoms have a major influence on the buckling behavior.

Abstract A three-dimensional finite element model is used to investigate the vibrational properties of double-walled silicon carbide nano-cones with various dimensions. The dependence of the vibrational properties of double-walled silicon carbide nano-cones on their length, apex angles and boundary conditions are evaluated. Current model consists a combination of beam and spring elements that simulates the interatomic interactions of bonding and nonbonding. The Lennard–Jones potential is employed to model the interactions between two non-bonding atoms. The fundamental frequency and mode shape of the double-walled silicon carbide nano-cones are calculated.

Bias correction (BC) is often a necessity to improve the applicability of global and regional climate model (GCM and RCM, respectively) outputs to impact assessment studies, which usually depend on multiple potentially dependent variables. To date, various BC methods have been developed which adjust climate variables separately (univariate BC) or jointly (multivariate BC) prior to their application in impact studies (i.e., the component-wise approach). Another possible approach is to first calculate the multivariate hazard index from the original, biased simulations and bias-correct the impact model output or index itself using univariate methods (direct approach). This has the advantage of circumventing the difficulties associated with correcting the inter-variable dependence of climate variables which is not considered by univariate BC methods. Using a multivariate drought index (i.e., standardized precipitation evapotranspiration index – SPEI) as an example, the present study compares different state-of-the-art BC methods (univariate and multivariate) and BC approaches (direct and component-wise) applied to climate model simulations stemming from different experiments at different spatial resolutions (namely Coordinated Regional Climate Downscaling Experiment (CORDEX), CORDEX Coordinated Output for Regional Evaluations (CORDEX-CORE), and 6th Coupled Intercomparison Project (CMIP6)). The BC methods are calibrated and evaluated over the same historical period (1986–2005). The proposed framework is demonstrated as a case study over a transboundary watershed, i.e., the Upper Jhelum Basin (UJB) in the Western Himalayas. Results show that (1) there is some added value of multivariate BC methods over the univariate methods in adjusting the inter-variable relationship; however, comparable performance is found for SPEI indices. (2) The best-performing BC methods exhibit a comparable performance under both approaches with a slightly better performance for the direct approach. (3) The added value of the high-resolution experiments (CORDEX-CORE) compared to their coarser-resolution counterparts (CORDEX) is not apparent in this study.

The increasing rate of occurrence of extreme events (droughts and floods) and their rapid transition magnify the associated socio-economic impacts with respect to those caused by the individual event. Understanding of spatio-temporal evolution of wet–dry events collectively, their characteristics, and the transition (wet to dry and dry to wet) is therefore significant to identify and locate most vulnerable hotspots, providing the basis for the adaptation and mitigation measures. The Upper Jhelum Basin (UJB) in South Asia was selected as a case study, where the relevance of wet–dry events and their transition has not been assessed yet, despite clear evidence of climate change in the region. The standardized precipitation evapotranspiration index (SPEI) at the monthly timescale was applied to detect and characterize wet and dry events for the period 1981–2014. The results of temporal variations in SPEI showed a strong change in basin climatic features associated with El Niño–Southern Oscillation (ENSO) at the end of 1997, with the prevalence of wet and dry events before and after 1997 respectively. The results of spatial analysis show a higher susceptibility of the monsoon-dominated region towards wet events, with more intense events occurring in the eastern part, whereas a higher severity and duration are featured in the southwestern part of the basin. In contrast, the westerlies-dominated region was found to be the hotspot of dry events with higher duration, severity, and intensity. Moreover, the surrounding region of the Himalaya divide line and the monsoon-dominated part of the basin were found to be the hotspots of rapid wet–dry transition events.

In this paper, surface and piezoelectric effects on the vibration behavior of nanowires (NWs) are investigated by using a Timoshenko beam model. The electric field equations and the governing equations of motion for the piezoelectric NWs are derived with the consideration of surface effects. By the exact solution of the governing equations, an expression for the natural frequencies of NWs with simply-supported boundary conditions is obtained. The effects of piezoelectricity and surface effects on the vibrational behavior of Timoshenko NWs are graphically illustrated. A comparison is also made between the predictions of Timoshenko beam model and those of its Euler-Bernoulli counterpart. Additionally, the present results are validated through comparison with the available data in the literature.

Despite its numerous potential applications, two-dimensional monolayer graphyne, a novel form of carbon allotropes with sp and sp2 carbon atoms, has received little attention so far, perhaps as a result of its unknown properties. Especially, determination of the exact values of its elastic properties can pave the way for future studies on this nanostructure. Hence, this article describes a density functional theory (DFT) investigation into elastic properties of graphyne including surface Young’s modulus and Poisson’s ratio. The DFT analyses are performed within the framework of generalized gradient approximation (GGA), and the Perdew–Burke–Ernzerhof (PBE) exchange correlation is adopted. This study indicates that the elastic modulus of graphyne is approximately half of that of graphene due to its lower number of bonds.

In this study, polypyrrole (PPy), polyaniline (PANi) and poly 3-methyl thiophene (P3MTh) conducting polymers were synthesized chemically as coated on the surface of wood sawdust (SD), then used for removal of arsenic ions (As3+) from aqueous solutions. The experiments were performed using both batch and column systems. In order to find out the possibility of desorption for frequent application, the chemical regeneration of the used column was also investigated

The activated carbon (AC) was used for removal of As(III) and As(V) ions from aqueous solutions. Sorption experiments were conducted using both batch and column systems. The effect of some important parameters on sorption of these by AC was studied. It was found that among the different factors affecting sorption capacity and efficiency in removal of arsenic from aqueous solutions, the effect of pH and the oxidation state were the most prominent. The optimum pH values for removal of As(III) and As(V) from aqueous solutions using AC was found 12 and 3 respectively. Impregnation of AC with sulphur contain organic dyes, it is possible to improve As(III) uptake considerably.

This paper deals with a new application of polyaniline synthesized chemically, coated on sawdust via cast method in the form of emeraldine base (EB) from formic acid as solvent, and used as an effective adsorbent for removal of mercuric ion or other heavy metals from aqueous solution. Among the different parameters investigated, the effect of pH was found to be the most prominent. It was found that metal uptake is occurred under neutral or slightly alkaline conditions, while under relatively strong acidic media, the sorption of the investigated metal ions was negligible and desorption is a predominant process.

Polyaniline was synthesized chemically, coated on sawdust via cast method in the form of emeraldine base (EB) from formic acid as solvent, and used as an adsorbent for removal of lead ion or from aqueous solution. The effects of some important chemical and physical factors in removal efficiency have also been investigated. Among the different parameters, the effect of pH was the most prominent. It was found that metal uptake is occurred under neutral or slightly alkaline conditions, while under relatively strong acidic media, the sorption of the investigated metal ions was negligible and desorption is a predominant process. It was found that undoped PANi (EB form) coated on polar substrates such as sawdust (SD) can be used as an effective adsorbent for removal of heavy metal ions in water and wastewater treatments. All the previous investigations and applications take advantage of the electrical conductivity (metallic), electrochemical (redox activity) and electrochromic properties of the polyaniline. While; in this research, we have taken advantage of the chelating properties of PANi for metal sorption.

The vibrational behavior of single-walled carbon nanocones is studied using molecular structural method and molecular dynamics simulations. In molecular structural approach, point mass and beam elements are employed to model the carbon atoms and the connecting covalent bonds, respectively. Single-walled carbon nanocones with different apex angles are considered. Besides, the vibrational behavior of nanocones under various types of boundary conditions is studied. Predicted natural frequencies are compared with the existing results in the literature and also with the ones obtained by molecular dynamics simulations. It is found that decreasing apex angle and the length of carbon nanocone results in an increase in the natural frequency. Comparing the vibrational behavior of single-walled carbon nanocones under different boundary conditions shows that the effect of end condition on the natural frequency is more prominent for nanocones with smaller apex angles.

On the basis of modified couple stress theory, the postbuckling behavior of the Euler-Bernoulli microscale FG beams is investigated by means of an exact solution method. The modified couple stress theory as a nonclassical continuum theory is capable of interpreting the size dependencies which become more significant at micro/nanoscales. The Von-Karman type nonlinear strain-displacement relationships are employed. The thermal effects are also incorporated into formulation. The governing equation of motion and the corresponding boundary conditions are derived using Hamilton’s principle. The material properties are assumed to be graded in the thickness direction according to the power-law distribution. A closed-form solution is obtained for the postbuckling deformation which is beyond the critical buckling load. To study the vibrations taking place in the vicinity of a buckled equilibrium position, the linear vibration problem is exactly solved around the first three buckled configurations. The natural frequencies of the lowest vibration modes around each of the first three buckled configurations are obtained. The influences of power-law exponent, boundary condition, length scale parameter, and thermal environment changes on the static deflection and free vibration frequencies are studied. A comparison is also made between the present results and those obtained via the classical beam theories.

The vibration behavior of piezoelectric microbeams is studied on the basis of the modified couple stress theory. The governing equations of motion and boundary conditions for the Euler-Bernoulli and Timoshenko beam models are derived using Hamilton’s principle. By the exact solution of the governing equations, an expression for natural frequencies of microbeams with simply supported boundary conditions is obtained. Numerical results for both beam models are presented and the effects of piezoelectricity and length scale parameter are illustrated. It is found that the influences of piezoelectricity and size effects are more prominent when the length of microbeams decreases. A comparison between two beam models also reveals that the Euler-Bernoulli beam model tends to overestimate the natural frequencies of microbeams as compared to its Timoshenko counterpart.

The rhizome of Zingiber officinale, stands as a time-honored component deeply rooted in the realms of traditional medicine, boasting a history spanning centuries. This expansive review endeavors to intricately dissect the multifaceted dimensions of Zingiber officinale, delving into its botanical intricacies, phytochemical constituents, and medicinal attributes. Our overarching goal is to cast a comprehensive light on the manifold applications of Zingiber officinale within the domains of health and wellness. Methodically integrate the wealth of existing knowledge surrounding the anti-inflammatory, antioxidant, and antimicrobial properties inherent in ginger. By doing so, we seek to unravel the potential therapeutic efficacy of ginger in the management of an array of health conditions. To achieve this objective, an exhaustive literature review was conducted, encompassing detailed examinations of botanical descriptors, comprehensive phytochemical analyses, and critical evaluations of clinical studies. Through this comprehensive exploration, we present a holistic and nuanced overview of Zingiber officinale. Our findings resonate with the versatility of ginger, underscoring its efficacy in mitigating not only nausea and digestive issues but also in addressing the complexities of inflammatory diseases. The culmination of our findings contributes significantly to a richer and more profound understanding of the versatile applications of ginger, positioning it as a compelling and promising subject for both further scientific inquiry and practical utilization. [ABSTRACT FROM AUTHOR]

Wounds that influence the liver are shockingly normal in more youthful individuals. This condition might introduce itself clinically as subclinical hepatitis, intense hepatitis, persistent hepatitis, remunerated liver constant infection, decompensated liver cirrhosis, intense liver disappointment, or intense on persistent liver disappointment. These indications are possible. A liver capability test would frequently take a gander at various different biochemical markers, including complete bilirubin, direct bilirubin, Serum glutamic oxaloacetic transaminase, Serum glutamate pyruvate transaminase, egg whites, supportive of thrombin time, and gamma-glutamyl transferase. Novel biomarkers are presently effectively accessible as an immediate outcome of current specialized leap forwards and applications. The utilization of creature models is the beginning stage for the examination of these biomarkers, with the concentrate then, at that point, moving to human subjects. They can offer data that is demonstrative as well as data about the visualization. They give some enlightening data on the histological condition of the liver. Notwithstanding, they are restricted by the circumstances that they think of themselves as in. By directing an examination of marks of liver harm in youngsters, this exploration shows new conceivable outcomes and philosophies for the determination of liver sickness in kids. Concentrates on that focus on individual biomarkers as a restorative place of section are something that might be plausible to investigate not long from now. Hepatology is a subspecialty that is still during the time spent developing, and one of its subspecialties is the investigation of biomarkers. The developing weight of worldwide liver sickness, the shortfall of side effects until late in the regular history of an illness that might require a very long time to show, the presence of an obtrusive reference test (liver biopsy) to evaluate infection seriousness, and the absence of powerful instruments to survey the viability of restorative mediations are a portion of the critical drivers for this exploration. Furthermore, the shortfall of side effects until late in the regular history of a sickness that might require a very long time to show is one more key driver for this examination. Moreover, one of the essential motivations behind why this study is being directed is because of the deficiency of dependable instruments with which to assess the viability of restorative methodologies. [ABSTRACT FROM AUTHOR]

Fatty liver disease that is not alcoholic, often known as non-alcoholic fatty liver disease, is a common and progressive liver ailment that is defined by an abnormal buildup of fat in the liver when significant alcohol use is avoided. Nonalcoholic fatty liver disease is a frequent and progressive liver disorder. A variety of conditions are referred to as nonalcoholic fatty liver disease, which might include nonalcoholic steatohepatitis and simple steatosis. which can eventually lead to cirrhosis and hepatocellular cancer. Among nonalcoholic fatty liver disease, simple steatosis is the most prevalent kind. Even though it is invasive and has various drawbacks, liver biopsy is still considered the gold standard for diagnosing and staging nonalcoholic fatty liver disease at the present time. As a result, there is an immediate need for noninvasive biomarkers that are capable of providing an accurate diagnosis, staging, and monitoring of the development of illness. In recent years, proteomic methods have emerged as potentially useful tools for the identification and validation of noninvasive biomarkers in nonalcoholic fatty liver disease. This development has place over the course of many years. The objective of this research study is to provide an overview of the existing situation of noninvasive proteomic biomarkers in nonalcoholic fatty liver disease as well as their possible implications in clinical practice. [ABSTRACT FROM AUTHOR]

In this paper, the free vibration behavior of post-buckled functionally graded (FG) Mindlin rectangular microplates are described based on the modified couple stress theory (MCST). This theory enables the consideration of the size-effect through introducing material length scale parameters. The FG microplates made of a mixture of metal and ceramic are considered whose volume fraction of components is expressed by a power law function. By means of Hamilton's principle, the nonlinear governing equations and associated boundary conditions are derived for FG micro-plates in the postbuckling domain. The governing equations and boundary conditions are then discretized by using the generalized differential quadrature (GDQ) method before solving numerically by the pseudo-arclength continuation technique. In the solution procedure, the postbuckling problem of microplates is investigated first. Afterwards, the free vibration of microplates around the buckled configuration is discussed. The effects of dimensionless length scale parameter, material gradient index and aspect ratio on the on the postbuckling path and frequency of FG microplates subject to arbitrary edge supports are thoroughly discussed.

Abstract In this paper, a size-dependent microscale plate model is developed to describe the bending, buckling and free vibration behaviors of microplates made of functionally graded materials (FGMs). The size effects are captured based on the modified strain gradient theory (MSGT), and the formulation of the paper is on the basis of Mindlin plate theory. The presented model accommodates the models based upon the classical theory (CT) and the modified couple stress theory (MCST) if all or two scale parameters are set to zero, respectively. By using Hamilton's principle, the governing equations and related boundary conditions are derived. The bending, buckling and free vibration problems are considered and are solved through the generalized differential quadrature (GDQ) method. A detailed parametric and comparative study is conducted to evaluate the effects of length scale parameter, material gradient index and aspect ratio predicted by the CT, MCST and MSGT on the deflection, critical buckling load and first natural frequency of the microplate. The numerical results indicate that the model developed herein is significantly size-dependent when the thickness of the microplate is on the order of the material scale parameters.