Analytical Scheme Research Articles

Portable near-infrared detection to replace color tests in an analytical scheme for forensic drug identification

In the ever-changing drug market the popularity and availability of substances is dynamic. In the Netherlands, ketamine and various cathinones have recently seen increased prevalence. It is crucial for law enforcement to quickly obtain an initial indication of the identity of a substance. This first test also serves as quality control for subsequent confirmation with GC–MS analysis. Traditionally, color tests have been used for these purposes. While these tests are quick and inexpensive, they have the disadvantage of reacting only to a few traditional drugs. Suitable color tests are not available for many new psychoactive substances (NPS). Near-infrared (NIR) spectroscopy is a rapid technique that provides a characteristic spectrum for organic compounds. This technique is more versatile than color tests and can adapt more quickly to market changes by incorporating reference spectra into the library. This study demonstrates the feasibility of obtaining a good quality NIR spectrum from a 20 mg sub-sample in a test tube. This was achieved by scanning the test tube through the glass bottom. In the routine analytical scheme, these test tubes were subsequently batchwise analyzed by GC–MS. From the NIR spectra, 84 % true positive and 100 % true negative results were achieved on 516 casework samples, including identification of substances without available color tests like ketamine. Missed false negatives primarily involved new substances absent from the library, emphasizing the need for continuous library updates. NIR’s adaptability to market changes is crucial, allowing the inclusion of new substances as they emerge. This method enhances law enforcement’s ability to make informed decisions, aiding in the indictment process.

Effective flexoelectric properties of inclusion-based composites based on strain gradient theory and homogenization technique

This study focuses on enhancing flexoelectricity in composites and develops a new micromechanical analytical framework to determine the effective electromechanical properties of inclusion-based flexoelectric composites within the context of SGE. Initially, we specialize in studying isotropic materials and derive the governing Navier equations for the problem. Subsequently, we streamline these differential equations by introducing a Laplacian-type gradient state variable, departing from higher-order gradient-enrichment treatments. The study employs Green’s functions and stress polarization tensors for spherical inhomogeneities, deriving homogenized material properties through volumetric averages of microscopic properties weighted by displacement localization operators. The analytical scheme’s relevance is validated against results from reference models and experimental data. Effective composite properties are evaluated using numerical methods, with an emphasis on assessing the impact of reinforcement on these properties. Our findings lay the foundation for developing a micromechanical method to predict the electromechanical behavior of composites. Specifically, we demonstrate the efficacy of our proposed theory by deriving effective flexoelectric properties of particulate composites.

HYBRID WAR IN MODERN SOCIAL AND POLITICAL DISCOURSE: NEW RESEARCH STRATEGIES

Attention is focused on the urgency of raising the level of conceptual understanding of the problem field of hybrid warfare. The author’s strategy for building a general concept of hybrid war is proposed. The first stage of which involves the systematization of the results of research into the problems of hybrid warfare, which are presented in the modern social and political discourse according to L. Coser’s analytical scheme. The second is the development of its «static» (fundamentals of sustainable existence) and «dynamic» (mechanisms of development and distribution) models.

Exploiting the Applicability of Polytetrahydrofuran-Modified Polyester for the Fabric Phase Sorptive Extraction of Doxycycline from Human Urine.

In this report, a polytetrahydrofuran-coated polyester fabric phase sorptive extraction (FPSE) for the determination of doxycycline in human urine was described. The sol-gel polytetrahydrofuran sorbent proved to be superior against other sol-gel coated cellulose and polyester membranes tested. The effect of the extraction parameters including membrane surface area, sample pH and volume, salt concentration, extraction time, stirring rate, etc., on the extraction efficiency of the analyte was studied using the "one-factor-at-a-time" (OFAT) and Box-Behnken design approaches. The analytical method proposed was validated in compliance with FDA guidelines for bioanalytical procedures. The method was linear in the determination range of 100-5000 ng/mL with the determination coefficient of 0.9953. The limit of detection (LOD) and the lower limit of quantification for doxycycline was 17 and 100 ng/mL, respectively. The relative recoveries for intra-day and inter-day studies ranged from 98.5-112.2% and 89.6-96.8%, respectively. The relative standard deviation was lower than 14.7% in all cases, exhibiting good precision. The sol-gel polytetrahydrofuran-modified FPSE membranes were reusable for at least 30 times. The greenness of the developed method was evaluated using Sample Preparation Metric of Sustainability (SPMS) and Blue Applicability Grade Index (BAGI) metric tools. Finally, the analytical scheme was successfully employed for the quantitation of urinary doxycycline collected at various time points following the administration of doxycycline-containing tablets.

Spatio-temporal variations and multi-scale correlations of climate, water, land, and vegetation resources over the past four decades in the Heihe River Basin

Study regionHeihe River Basin (HRB), Northwest China. Study focusThe study proposes an analytical scheme to identify trend, periodicity, and scale-correlation in climate, water, land, and vegetation resources over the past four decades using multivariate remote sensing data. New hydrological insights for the regionHeat and precipitation resources in the HRB have increased at rates of 14.27℃ yr−1 and 1.26 mm yr−1, respectively. The glacier area has decreased by 47.47 %. Additionally, the increase in upstream precipitation (2.82 mm yr−1) and glacier meltwater effectively replenishes runoff, soil water, and groundwater. The implementation of the ecological water diversion project (EWDP) in 2000 has contributed to enhancing runoff and lake storage capacity. The 9.28 % increase in vegetation cover (including cropland, forest, grassland, and shrubland) indicates an improvement in the hydrothermal conditions of the HRB. Additionally, the magnitude and direction of interactions among various natural resources vary across multiple spatial scales and time scales. The effect of hydrothermal coupling on vegetation is more prominent at the interdecadal scale. Vegetation growth in the upstream area is primarily influenced by thermal condition, while moisture plays a significant role in the midstream and downstream areas. Knowledge from this study contributes to the informed allocation of natural resources and offer policymakers valuable insights to enhance eco-environmental sustainability.

Theoretical study of the MWCNT particle layer and size impact on sodium alginate heat transfer

This paper theoretically studies the effects of the size of multiwalled carbon nanotube (MWCNT) nanoparticles and layers on the flow of sodium alginate (SA) base fluid in a vertical channel. The nanoparticles are used to improve the thermal characteristics of the base fluid. The nanolayer shows the relationship between the particles and the base fluid, justifying the rise in thermal conductivity, even at a low volume of the nanoparticle in the base fluid. The mechanics of the fluid through the channels are developed using nonlinear models of coupled higher order differentials analyzed using the adomian decomposition method, an analytical scheme. The nanolayer effect of MWCNT particles on pure sodium alginate enhances heat transfer by 31.83% upon a step increase of 0.4 from 0.2 nm. Additionally, the combined effects of the rheological parameters of particle size, radiation and shear stress lead to a high heat transfer rate. The results obtained from the analysis were verified with results obtained from the literature for simple conditions, which validated the analysis. The results of this study may provide meaningful insight into the physical application of the sodium alginate.

Temperature Field Analytical Solution and Optimization Scheme after Excavation in Large-scale Ground Freezing Projects

Temperature Field Analytical Solution and Optimization Scheme after Excavation in Large-scale Ground Freezing Projects

Radiative transfer simulations of water-leaving radiance from the Skylight-Blocked Approach.

Radiative transfer simulations of measurements performed with the Skylight-Blocked Approach (SBA) for water exhibiting diverse optical properties confirmed the non-negligible impact of the depth z0 of the radiometer shield in the determination of the water-leaving radiance Lw. In particular, results showed that the shield-shaded water volume lowers the measured Lw value by a few up to tens of percent as a function of the depth z0, water attenuation, and wavelength. The study also confirmed the potential applicability of an analytical correction scheme based on the sole water absorption and backscattering coefficients to support operational SBA measurements, still at the expense of decreased accuracy with increasing depth z0 and water turbidity.

Rights That

Abstract Hohfeld was acutely aware of the ‘potent tendency [of words] to control thought’. He was perhaps less aware of the power of syntax to do the same. Hohfeld’s tendency to express the content of duties and liberties in the syntactically restrictive to ϕ form has allowed a corrupted version of his analytical scheme to take root. That version takes as axiomatic that the content of any duty or liberty is the action or inaction of the duty bearer or liberty holder. Yet duties and liberties can (and do) pertain to matters other than the action or inaction of the duty bearer or liberty holder. This insight has a range of doctrinal implications.

Analytical Scheme for Time Fractional Kawahara and Modified Kawahara Problems in Shallow Water Waves

The Kawahara equation exhibits signal dispersion across lines of transmission and the production of unstable waves from the water in the broad wavelength area. This article explores the computational analysis for the approximate series of time fractional Kawahara (TFK) and modified Kawahara (TFMK) problems. We utilize the Shehu homotopy transform method (SHTM), which combines the Shehu transform (ST) with the homotopy perturbation method (HPM). He’s polynomials using HPM effectively handle the nonlinear terms. The derivatives of fractional order are examined in the Caputo sense. The suggested methodology remains unaffected by any assumptions, restrictions, or hypotheses on variables that could potentially pervert the fractional problem. We present numerical findings via visual representations to indicate the usability and performance of fractional order derivatives for depicting water waves in long-wavelength regions. The significance of our proposed scheme is demonstrated by the consistency of analytical results that align with the exact solutions. These derived results demonstrate that SHTM is an effective and powerful scheme for examining the results in the representation of series for time-fractional problems.

Dynamics of stratified-convected Eyring-Powell nanoliquid featuring chemically reactive species and Ohmic dissipation: Application of Levenberg-Marquardt artificial neural networks(ALM-ANNs)

Magnetic nanoliquids are pondered cutting-edge heat transference liquids, representing a modern generation because of their aptitude to function as smart liquids. The deployed magnetism externally exerts a readily manageable impact, escalating their adaptableness and practicality in various applications. In this analysis, electro magnetized Powell-Eyring rheological nanoliquid is modeled considering stretching cylinder based buoyancy-driven flow. Transport expressions include thermal radiation, Brownian diffusion, chemical reaction, thermophoresis, and thermal source effect. Prandtl theory of boundary-layer (BL) assists to develop the governing problems. Appropriate transformations are deployed to obtain the dimensionless problems which are then computed numerically through the novel Levenberg-Marquardt artificial neural networks(ALM-ANNs). It is worth to mention that the close agreement between the error analysis of the reference dataset and the proposed datasets roughly from E−10 to E−03, further justifies the approaches utilized in this study. Besides the excellent measures of performance in terms of MSE are achieved at level 5.77E−11, 4.41E−11, 2.09E−12, 2.16E−11, 1.03E−11, 1.65E−11, 2.00E−11, and 1.91E−11against 272, 416, 266, 391, 142, 366, 425, and 508 epochs for first instance of all eight various scenarios. The acquired outcomes are compared with alternate analytical (homotopy) scheme and good agreement is witnessed. Furthermore it is noticed that as the values of Pr,RandS1 increase in size, so does the EPFM temperature profile θ, and the evaluation of AE is between E-04 to E-10.

Exact dispersion relation of the quantum Langmuir wave.

The normal modes, i.e., the eigensolutions to the dispersion relation equation, are the most fundamental properties of a plasma. The real part indicates the intrinsic oscillation frequency while the imaginary part the Landau damping rate. In most of the literature, the normal modes of quantum plasmas are obtained by means of small damping approximation, which is invalid for high-k modes. In this paper, we solve the exact dispersion relations via the analytical continuation scheme, and, due to the multi-value nature of the Fermi-Dirac distribution, reformation of the complex Riemann surface is required. It is found that the topological shape of the root locus in quantum plasmas is quite different from classical ones, in which both real and imaginary frequencies of high-k modes increase with k steeper than the typical linear behavior in classical plasmas. As a result, the time-evolving behavior of a high-k initial perturbation becomes ballistic-like in quantum plasmas.

ADAPTIVE CONTROL OF A SUBMARINE FOR VARIOUS DIVING DEPTHS USING AN EXPONENTIAL

Due to the progress of deep submergence capabilities, a submarine is extensively employed on many sides of marine science. For that reason, it has become necessary to design an effective submarine position controller while achieving a fast and stable mission. An adaptive analytical scheme for the underwater submarine was developed. The main purpose of the adaptive analytical scheme is to provide a powerful analytical controller that can successfully steer the submarine from the current state under the water to the surface of water in a short time. To achieve that, a seventh-term exponential function was proposed to reshape the reference diving depth while maintaining the control variable limitation and satisfying initial and final boundary conditions. The direct search method with two cascade loops was employed to achieve a minimum cost function by determining an appropriate constant of the function and minimum final time. However, using the direct search method can be time-consuming since a number of algebraic operations are executed inside these two loops. Therefore, the curve fitting method was used to fit the set of direct search method data using power functions. Then, at a certain diving depth, the function coefficients were computed based on the final settling time and function constant using the Gaussian elimination method. A nominal numerical simulation of the submarine’s model was implemented using both adaptive analytical and linear controllers.

Kriterien für wirtschaftspolitische Maßnahmen zum Abbau kritischer Importabhängigkeiten

Abstract In this study, an analytical scheme is developed to operationalise the objective of strategic autonomy in a cost-effective way. This is highly relevant as the concept of strategic autonomy is fuzzy and can therefore easily be misinterpreted in a way that would lead to large government subsidies for inefficient purposes in a time of high public debts, low growth and many other public spending needs. The main criteria of the analytical scheme are the degree of critical import dependency on a specific product, the existence of production in the EU and a long-term comparative advantage for this product, as well as the possibility of diversified friend-shoring to secure the supply of this product. Based on a product-specific evaluation of these criteria, it can be determined whether or not government intervention is justified in order to achieve sufficient de-risking of critical import dependencies. This is illustrated using several examples, including raw materials, pharmaceuticals, electric vehicles, batteries for electric vehicles and solar modules. If government intervention is found to be justified, the choice of instrument should be based on the principle that the degree of intervention should be minimised, provided that de-risking objective is sufficiently achieved. Several instruments such as warehousing, incentives for firm-based de-risking, trade barriers and subsidies are discussed. Subsidies in general should be the last resort.

Semi analytical scheme for the presentation of solution to Fractional Fokker–Planck Equation

In this work, we have also proposed new semi analytical scheme combining least-squares and asymptotic homotopy perturbation methods AHPM for the solution of Fractional Fokker–Planck Equation (FFPE). The Caputo version of derivative is used. The finding of this work is fast convergence of the AHPM to the solutions of linear and nonlinear applied problems. AHPM is a modified form of the HPM and is particularly useful for solving problems with small or large parameters. This can be seen as a clear advantage of this new semi analytical method over existing methods because its implementation and the calculation involved in it are much simpler and easier. The proposed method solved the problems without using Ji-Huan He and Adomian polynomials. Numerical solutions obtained in this way show that this approach is simple and computationally very attractive. An error estimate for the solution is also provided. Approximate solutions of AHPM are tabulated and graphically displayed to show that AHPM is effective and accurate.

The trustification of AI. Disclosing the bridging pillars that tie trust and AI together

Trustworthy artificial intelligence (TAI) is trending high on the political agenda. However, what is actually implied when talking about TAI, and why it is so difficult to achieve, remains insufficiently understood by both academic discourse and current AI policy frameworks. This paper offers an analytical scheme with four different dimensions that constitute TAI: a) A user perspective of AI as a quasi-other; b) AI's embedding in a network of actors from programmers to platform gatekeepers; c) The regulatory role of governance in bridging trust insecurities and deciding on AI value trade-offs; and d) The role of narratives and rhetoric in mediating AI and its conflictual governance processes. It is through the analytical scheme that overlooked aspects and missed regulatory demands around TAI are revealed and can be tackled. Conceptually, this work is situated in disciplinary transgression, dictated by the complexity of the phenomenon of TAI. The paper borrows from multiple inspirations such as phenomenology to reveal AI as a quasi-other we (dis-)trust; Science & Technology Studies (STS) to deconstruct AI's social and rhetorical embedding; as well as political science for pinpointing hegemonial conflicts within regulatory bargaining.

AOPC-based control for efficient uncertainty mitigation in UASB wastewater treatment with multiple manipulated variables and distributed biomass integration

This study proposes an adaptive optimal predictive control (AOPC) for the upflow anaerobic sludge blanket (UASB) reactor with recirculation, employing a PDE-ODE system. Effectively addressing complexity and uncertainties associated with Danckwerts-boundary conditions and biomass distribution, an analytical model predictive control scheme incorporates adaptive set points and compensators. By dynamically adjusting multiple manipulated inputs, including the feed flow rate and recirculation-to-feed ratio, the controller achieves precise effluent concentration control. The robustness of the control system is investigated through fluctuations in inlet concentrations (15–30 %) and variations in bacterial growth rates (10–30 %). The control performance index, ISE, indicates that the AOPC-based control system outperforms the PI controller by 28–150 times for inlet concentration variations and 3–84 times for growth rate changes. With a settling time of 1–3 days, the proposed system excels over the conventional controller, which consistently struggles to maintain the target, emphasizing its inherent robustness.

Aeroelastic analysis of a lightweight topology-optimized sandwich panel

Sandwich structures with lattice cores are novel, lightweight composite structures and are widely used in the aerospace industry. Besides, the aeroelastic behavior of sandwich panels in a supersonic flow regime still needs to be thoroughly studied. This work investigates the supersonic flutter of a sandwich panel whose core is topology-optimized. A finite element model of a sandwich panel based on the layerwise theory, coupled with the first-order piston theory, is presented. The sandwich panel core is assessed using a topology optimization approach with flutter loading constraints. The subsequent analytical homogenization scheme is developed to provide the equivalent mechanical properties of the topology-optimized panel. The modeling approach is fully validated, and the results demonstrate that the sandwich panel is capable of enlarging the flutter-free operational flight range when compared with other conventional panel designs. A parametric analysis of the topology-optimized sandwich panel regarding the critical flutter conditions is performed.

Analytical buckling scheme of a functionally graded porous liner reinforced by nanocomposites encased in an egg-shaped pipe

This study uses the FGP-GPLs (functionally graded porous metal reinforced by graphene platelets) to rehabilitate the egg-shaped liner-pipe system. The water penetrates the cracked pipe and surrounds the thin-walled liner, resulting in hydrostatic pressure that may contribute dominantly to the buckling of the thin-walled liner. The critical buckling pressure is derived analytically by combining the thin-walled shell theory, a refined displacement function, and the energy scheme. It is found the egg-shaped FGLs liner sustains higher buckling pressure than the circular FGP-GPLs one. Furthermore, a finite element model is developed to verify the theoretical solutions. The results indicate the numerical equilibrium paths agree well with the analytical ones. In addition, the present analytical predictions are compared successfully with other close-formed solutions. Finally, parametric analyses indicate that the addition of GPLs may significantly improve the stability of the egg-shaped liner, while the increase of pores decreases the stability of the liner. The thickness of the GPLs has a slight effect on the stability of the liner when the volume of GPLs is constant. Thus, thick GPLs may be recommended in engineering practices to reduce the manufacturing cost.

A constructivist grounded theory of Queer and Muslim identity integration in college

The constructivist grounded theory (CGT) explored how queer Muslim college students integrate their religious and sexual identities. By using intensive interviews concurrent with an iterative analytical scheme, the study identified a cycle of identity integration. Findings suggest that queer Muslim college students navigated identity gatekeepers by redefining religious truths and reflecting on their beliefs. They contextualized themselves within their communities as they preserved their familial connections and cultural congruity. Queer Muslims also disrupted taken-for-granted notions of authenticity through a process of selective outness and differentiated religion from culture and belief to process cultural attitudes and construct a more cohesive and integrated identity as both queer and Muslims. The CGT sheds light on the complexity of the Muslim identity and troubles religious structures by highlighting collectivist paradigms, nuancing self-authorship, and complicating the nexus between religion and culture.