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Amphiphobic fluoroalkyl chains are exploited for creating robust and diverse self‐assembled biomimetic catalysts. Long terminal perfluoroalkyl chains (CnF2n+1 with n=6, 8, and 10) linked with a short perhydroalkyl chains (CmH2m with m=2 and 3) were used to synthesize several 1,4,7‐triazacyclononane (TACN) derivatives, CnF2n+1‐CmH2m‐TACN. In the presence of an equimolar amount of Zn2+ ions that coordinate the TACN moiety and drive the self‐assembly into micelle‐like aggregates, the critical aggregation concentration of polyfluorinated CnF2n+1‐CmH2m‐TACN⋅Zn2+ was lowered by ∼1 order of magnitude compared to the traditional perhyroalkyl counterpart with identical carbon number of alkyl chain. When 2'‐hydroxypropyl‐4‐nitrophenyl phosphate was used as the model phosphate substrate, polyfluorinated CnF2n+1‐CmH2m‐TACN⋅Zn2+ assemblies showed higher affinity and catalytic activity, compared to its perhyroalkyl chain‐based counterpart. Coarse‐grained molecular dynamic simulations have been introduced to explore the supramolecular assembly of polyfluoroalkyl chains in the presence of Zn2+ ions and to better understand their enhanced catalytic activity. [ABSTRACT FROM AUTHOR]

Cumin and eucalyptus essential oils (EOs) are among the most important and widely used EOs with a broad range of applications in the pharmaceuticals, cosmetics, and food industries. The seeds and leaves of cumin (Cuminum cyminum) and eucalyptus (Eucalyptus globulus) plants are processed with extraction techniques to retrieve their EOs, yet certain product specifications need to be met to achieve a high-quality product. Based on the International Organization for Standardization (ISO), the essential oils of cumin and eucalyptus should contain certain amounts of cuminaldehyde and 1,8-cineole to be of acceptable quality. In this study, we design and optimize a dynamic fractional distillation process that enriches cumin and eucalyptus EOs to the ISO standards, with concentrations of 42% cuminaldehyde and 80% of 1,8-cineole achieved for each EO respectively. The dynamic model of this process is simulated via Aspen Plus using data from a pilot-scale fractional distillation unit, and the operating conditions that minimize the operational cost in the simulated environment are identified using the NOMAD algorithm. The optimization results show that the operating cost of standardization processes for cumin and eucalyptus EOs are $0.688/batch and $0.6973/batch, with process efficiencies of 69.56% and 59.77%, respectively. Furthermore, the techno-economic analysis for these two standardization processes showed that the total annualized cost was approximately $510,600 for both processes. [ABSTRACT FROM AUTHOR]

The integration of offshore wind energy into Power‐to‐X (PtX) process chains offers opportunities for the efficient use of renewable energy. This article analyzes different PtX process chain configurations and their adaptation to the offshore environment. However, direct coupling of PtX platforms with fluctuating electrical energy poses major challenges. Dynamic process simulation is presented for analysis of different plant configurations and operating strategies. The article emphasizes the need for interdisciplinary research to consider technological as well as economic and environmental aspects. [ABSTRACT FROM AUTHOR]

The vibration of the rolling mill has been a persistent issue affecting its safe and stable operation. To address the vibration problem in the F2 stand of a continuous rolling mill, this paper establishes a digital twin model of the rolling mill. Based on the digital twin model, a rolling mill virtual commissioning framework has been proposed to enhance the accuracy of real-time data and improve the utilization of production data, laying the foundation for reducing vibration during the operation of the rolling mill. In this process, we first construct a digital twin framework for the rolling mill, consisting of four levels: physical rolling mill, virtual rolling mill, twin data, and services. Next, an online data acquisition and virtual commissioning framework is established to achieve a state mapping from the physical rolling mill to the virtual rolling mill. Finally, using the digital twin model, the effects of real-time process parameter optimization are analyzed. The impact of process parameter optimization on the dynamic response of the rolling mill system is examined. The optimized rolling process parameters effectively reduce the vertical vibration of the rolling mill system. [ABSTRACT FROM AUTHOR]

Time-domain or transient dynamic response method is the most traditional method used to evaluate the dynamic response of a vibratory system subjected to deterministic inputs. The inertia or damping effects are very crucial in the time scale of loading. The present work determines the time domain analysis of railway locomotive using finite element analysis for Indian tracks. The track inputs are modelled as an ellipsoidal bump, and variations in displacement at different key locations of the truck and carbody models are plotted subjected to standard loading conditions. The response plot of the front and rear locations of the locomotive truck and carbody indicate that these regions are more responsive to wheel inputs in comparison to the mid portion due to unbalanced mass distribution. In the further study vertical-lateral random inputs are measured through track recording car and modelled to express in the form of PSD. These random inputs are provided to finite element modelled flexible bogie frame, and acceleration response is determined. The results obtained are compared with the same obtained from rigid bogie frame formulated using an analytical model. The results obtained from the flexible and rigid body models are found to be in good agreement. [ABSTRACT FROM AUTHOR]

The following paper proposes a modern method of obtaining an extract from Viola tricolor L. with a high rutin content and enhanced antioxidant activity. Conventional isolation of active substances from plant raw material is high‐cost, elaborate and often harmful to the environment. The ultrasonic assistance micelle‐mediated extraction method (UAMME) and the cloud‐point extraction/separation technique are interesting alternatives. This work discusses the relationship between salt concentration and the cloud‐point extraction (CPE) yield. The molecular dynamic simulations investigated the impact of hydrocarbon chain length and the ratio of oxyethylene/oxypropylene units of model surfactants on the interactions between extraction system components. Micellar extract from the Viola tricolor was obtained using C9‐11 Pareth‐5 at 1 wt/vol% and subsequently concentrated by CPE with the addition of NaCl in concentrations from 5% to 30%. For comparison, water and ethanol extracts were also prepared. Antioxidant properties, polyphenols and flavonoid contents were measured for all samples. The HPLC method was used to determine the rutin concentration. The simulation part of the study confirmed the dependence of bioflavonoid solubilization efficiency on the surfactant structure. The determined descriptors allowed for finding the optimal structure of the model surfactants and gave a hint for their application to obtain extracts with high concentrations of antioxidants. [ABSTRACT FROM AUTHOR]

Background: While the development of CT imaging technique has brought cognition of in vivo organs, the resolution of CT images and their static characteristics have gradually become barriers of microscopic tissue research. Purpose: Previous research used the finite element method to study the airflow and gas exchange in the alveolus and acinar to show the fate of inhaled aerosols and studied the diffusive, convective, and sedimentation mechanisms. Our study combines these techniques with CT scan simulation to study the mechanisms of respiratory movement and its imaging appearance. Methods: We use 3D fluid‐structure interaction simulation to study the movement of an ideal alveolus under regular and forced breathing situations and ill alveoli with different tissue elasticities. Additionally, we use the Monte Carlo algorithm within the OpenGATE platform to simulate the computational CT images of the dynamic process with different designated resolutions. The resolutions show the relationship between the kinematic model of the human alveolus and its imaging appearance. Results: The results show that the alveolus and the wall thickness can be seen with an image resolution smaller than 15.6 μm. With ordinary CT resolution, the alveolus is expressed with four voxels. Conclusions: This is a preliminary study concerning the imaging appearance of the dynamic alveolus model. This technique will be used to study the imaging appearance of the dynamic bronchial tree and the lung lobe models in the future. [ABSTRACT FROM AUTHOR]

• The coolprop thermodynamic equations of state and the implicit fitting method have been investigated for calculating the refrigerants' thermodynamic properties. • A dynamic cascade refrigeration cycle has been developed and simulated with both methods for comparison. • The simulation was 30 times faster with the implicit fitting method than coolprop equations of state. • The implicit fitting method showed high accuracy. Modeling and simulating dynamic and complex energy systems that are composed of a large number of components where every component model is described by mathematical equations can take high computational time. The calculation of the refrigerant thermodynamic properties has a big impact on the computational speed of the model. In an attempt to speed up simulations, two implementation methods for the calculation of refrigerants' thermodynamic properties were investigated, the Coolprop thermodynamic equations of state and the Implicit fitting method. A complex dynamic cascade refrigeration cycle was developed and simulated using the two fluids implementation methods. The advantages and disadvantages of each method were discussed. The results show that using the implicit fitting method instead of Coolprop for the simulations of complex dynamic systems in Dymola will accelerate the simulation by about 30 times. In addition, the implicit method is accurate and offers more flexibility for modeling complex realistic energy systems. [ABSTRACT FROM AUTHOR]

In a previous work, a solar chimney power plant integrated with a solid sorption cooling system for power and cold cogeneration was developed. This prior work showed that reusing the heat released from the adsorption bed enhances the system's utilization of solar energy and increases the turbine's output power. In the present paper, a subsequent modification to the arrangement and operation of the preceding system is introduced. The primary objective of the modification is to enhance performance and increase the plant's capacity to effectively harness the available solar radiation. The method involves placing the condenser tubes at the solar collector entrance. Therefore, the airflow captures the condenser-released heat before it enters the collector. The modified configuration and operation of the system are discussed. A dynamic mathematical model is established to simulate the hybrid system's operation and evaluate its parameters. The obtained results show that a 5.95% increase in output power can be achieved by recovering the heat of condensation. Furthermore, the modified system attains a 6% increase in solar-to-electricity conversion efficiency compared with the basic system. The findings suggest that the modified system, which recycles condenser heat, provides noticeable enhanced performance compared with the basic system. [ABSTRACT FROM AUTHOR]

Energy-feed power electronic loads can precisely control the phase and magnitude of the power supply output current, achieving the emulation of loads. Moreover, they can feed energy back to the grid for energy regeneration, demonstrating significant research value. This article proposes an energy-fed power electronic load topology and control method that can realize the static and dynamic simulation of linear and non-linear loads and take into account the simulation needs of single-phase, three-phase three-wire, and three-phase four-wire loads. The main circuit uses a two-stage back-to-back AC/DC/AC structure: the front side is a three-phase four-wire split capacitor PWM rectifier bridge, which is used to simulate loads under various operating conditions; the back side is a three-phase three-wire PWM inverter bridge, which realizes the energy feeding back to the grid and reduces the waste of energy; and the intermediate side uses a split capacitor to equalize the voltage and achieve voltage stabilization. The topology is analyzed under the simulation demands of three-phase balanced, three-phase unbalanced, single-phase and non-linear loads. Finally, a MATLAB(R2022a)/Simulink simulation platform is built for a power electronic load with a rated capacity of 200 kVA. The simulation results verify the effectiveness, feasibility, and advancement of the power electronic load proposed in this article. [ABSTRACT FROM AUTHOR]

A combined experimental and molecular dynamic simulation approach was used to examine the structure and interfacial properties of solute-saturated micelles. The properties of dodecylbenzenesulfonate (DBS) micelles were examined in dodecane and benzene hydrocarbon systems. Pyrene fluorescence was used to determine the aggregation number of surfactant monomers in the micelle systems. Molecular dynamic (MD) simulations using energy minimization applying the CHARMm force field with the TIP3P model for water. Comparison of the DBS/benzene and DBS/Dodecane micelles equilibrium structures via radial distribution function (RDF) and probability distribution function (PDF) analysis indicates that the area per head group for the DBS/Benzene micelle interface is significantly larger than that of the DBS/Dodecane at the interface. It was also determined that benzene molecules can move freely within the micelle while dodecane is strictly confined in the core of the micelle. The increased interfacial area per monomer caused by the insertion of benzene also reduces the effectiveness of the surfactant, which has implications for use in various environmental applications. However, the DBS/benzene micelle can solubilize many more hydrocarbon molecules in one micelle with less surfactant monomer (i.e., lower aggregation number) per micelle due to the increased available packing positions within the micelle. This, in turn, increases the efficiency of the surfactant in real-world applications which is consistent with previous laboratory results. Understanding the differing solubilization characteristics of surfactants against various classes of hydrocarbons in single solute systems is a necessary step to beginning to understand their solubilization properties in the mixed waste systems prevalent in most surfactant enhanced remediation (SEAR) strategies. [ABSTRACT FROM AUTHOR]

This paper aims to present two approaches for repeated-pole plus dead-time (RPPDT) models identification procedures for highorder processes based. First approach is based on using two or three points over the process reaction curve −an open-loop test− whereas the second approach is based on the use of the process relay control oscillating signals −a closed-loop test. Equations are provided for both model parameters identification as well as order estimation. Comparison tests confirm that the RPPDT models provide a better representation of the high-order process dynamics than its simple, usually employed, first-order approximation. These models are suitable for process representation in dynamic simulations and control system design studies. [ABSTRACT FROM AUTHOR]

Quantitative characterization of tight sandstone oil migration and accumulation is an emerging research frontier in the field of oil and gas exploration. In this study, a conceptual model containing multiple basic geological elements is developed, and a nonlinear seepage numerical model for tight sandstone oil migration and accumulation is established. The effects of the slip effect, overpressure driving force, buoyancy, and capillary force on the migration and accumulation of tight oil are examined. The results showed that (1) the differences in oil migration and accumulation between tight and conventional reservoirs are reflected in the growth mode of oil saturation, distribution characteristics of oil and water, and extent of the effect of the formation dip angle; (2) the slip effect has a significant impact when the average pore throat radius is less than 150 nm and the overpressure driving force and capillary force are the main mechanical mechanisms controlling oil migration and accumulation in tight sandstone, while the coupling effect of buoyancy, capillary force, and overpressure driving force controls the upper and lower limits of oil saturation. Finally, a dimensional and dimensionless identification chart for rapidly predicting the oil saturation of tight sandstone is proposed and verified using the measured data. This study provides a basis for analyzing the migration and accumulation mechanisms of tight sandstone oil and a new approach for predicting oil saturation. Additionally, we developed digital and visual analysis methods for the migration results, enriching the expression of the dynamics of hydrocarbon accumulation. [ABSTRACT FROM AUTHOR]

Based on the inverse piezoelectric effect and other characteristics of piezoelectric ceramics, a new type of piezoelectric variable friction damper is developed, and the output performance test of piezoelectric ceramic actuator and piezoelectric variable friction damper is carried out, and the parametric mechanical model of the damper is established by using Simulink to carry out numerical simulation, and compared and analyzed with the test results. The results of the study show that the simulation and the test present a good regular agreement. With the increment of loading voltage, the displacement deformation and zero-displacement thrust of piezoelectric ceramic actuator are approximately linear with the loading voltage; when the loading voltage is increased by 15V every time, the test value of the output damping force of the damper increases by 259.66N on average step by step, and the simulated value increases by 256.14N step by step, and the damping force has a linearly incremental relationship with the voltage and the slope of the linear increase is 16.434. [ABSTRACT FROM AUTHOR]

This paper explores the utilization of the excess capacity of monopiles supporting offshore wind turbines (OWTs) by deploying hybrid and colocated wave and current marine energy concepts. However, there is a lack of guidance in literature and standards relating to the evaluation of natural frequency and foundation damping for monopile-supported wind turbines in shared anchoring configurations. The work presented here represents one of the first studies quantifying the dynamic characteristics of simulated colocated and hybrid energy systems sharing the anchoring capacity of OWT monopiles. A 3D finite-elements numerical model is developed and used to perform dynamic simulations of the OWT monopile. The hybrid system is modeled as a marine hydrokinetic device represented by an annulus plate installed around the monopile perimeter, providing additional mass participating in system damping and vibration while inducing additional loading due to drag forces on its perimeter. For a colocated system, tension forces from the mooring lines of a wave hydrokinetic device are first computed by ANSYS-AQWA then these forces are applied to the monopile in the 3D numerical model. The dynamic analyses are first performed to calibrate the numerical model parameters using data from three existing OWT projects (i.e., Burbo Bank, Walney 1, and Gunfleet Sands). Results from a parametric study varying diameter and length of the monopile, demonstrated the effect of the added mass in the hybrid configuration, as well as the influence of the tension forces of the mooring lines in the colocated configuration on the natural frequency and foundation damping. Results indicate that the simulated hybrid and colocated systems do not alter the natural frequency of the system; however, the foundation damping of the hybrid system is approximately 1.5 to 2 times higher than that of the monopile supporting only the wind turbine tower. Results also demonstrated the minimum obtained natural frequency (f1,dmin) for a combination of diameter, length, and relative densities (i.e., DP = 5 m, LP = 38 m, and DR = 25%–100%) is higher than the minimum frequency of the dynamic loading caused by the passing blades (f3P,min = 0.25 Hz) while the maximum obtained natural frequency (f1,dmax) is lower than the maximum frequency of the 3P dynamic load (f3P,max = 0.65 Hz). As such, for the cases analyzed herein, f1,d falls within the frequency range of the 3P dynamic load, and the system operates in-between the two frequency zones of soft–stiff and stiff–stiff. To ensure operational natural frequency within the soft–stiff zone in these cases, reducing the dimensions of the tower would be necessary. [ABSTRACT FROM AUTHOR]

During the stance phase of a normal gait, the triceps surae muscle controls the advancement of the tibia, which contributes to knee extension. Plantar flexor weakness results in excessive dorsiflexion, and consequently, the knee loses this contribution. However, increasing knee flexion is also seen in patients with cerebral palsy who do not have plantar flexor weakness. We aimed to understand this mechanism through the use of a musculoskeletal dynamic model. The model consists of solid segments connected with rotatory joints and springs to represent individual muscles. It was positioned at different degrees of ankle plantarflexion, knee flexion, and hip flexion. The soleus muscle was activated concentrically to produce plantarflexion and push the foot against the ground. The resulting knee extension was analyzed. The principal determinant of knee flexion or extension associated with ankle plantarflexion was the position of the knee joint center. When this was anterior to the line of action of the ground reaction force (GRF), the soleus contraction resulted in increased knee flexion. The knee extension was obtained when the knee was flexed less than approximately 25°. The relation between joint angles, anthropometric parameters, and the position of the GRF was expressed in a mathematical formulation. The clinical relevance of this model is that it explains the failure of plantar flexor control on knee extension in patients with cerebral palsy, when increased knee flexion can occur even if there is a normal or plantarflexed foot position. [ABSTRACT FROM AUTHOR]

Depression, along with grief and anxiety, is currently one of the most common mental illnesses. It was placed 25th among the major diseases. QSAR (CoMFA) of 37 compounds with MAO-A inhibitory activity yielded the most significant QSAR model, m.3, with r²= 0.963, SDEC= 0.129, q² = 0.742, SDEP= 0.34. Using the lead likeness matrix, thirty-seven 1,5-disubstituted MAO-A inhibitors were developed and tested based on the QSAR models. The top 13 compounds were identified. Furthermore, compound 2B (ΔG: -10.3 kcal mol-1, RMSD: 0.151 Å) was selected among the top 13 hits obtained from molecular docking experiments. Significant interactions were also observed, including π-π contacts with Phe208, Tyr444, Trp407, and hydrogen bond interactions with Ala68 and Tyr69. Furthermore, dynamic modelling demonstrated that compound 2B (0.11 nm) has higher overall stability than clorgyline, with a lower RMSD value, and may reach equilibrium in the final 20-25 ns. In terms of RMSF, 2B produced around 0.34 nm with less variation than clorgyline. Throughout the simulation, 2B (No. of H-bond: 6) had more hydrogen bonding than clorgyline (No. of H-bond: 3) with the highest occupancy, i.e. 117.39% for GLU216, 29% for TYR444, and 49% for PRO72, and so on. Compound 2B was proven to be the most essential throughout the experiments. These new chemicals will be optimized in vitro and in vivo in the future. This study will surely contribute to the development of novel MAO-A inhibitors for the treatment of depression. [ABSTRACT FROM AUTHOR]

Context: Electronic sustainable behavior on the material surface and in situ metal configuration were accompted with some metal atoms like Li, Na, and K elements. Metal-doped ZrO2 crystal exported modified characteristics related to electronic conduction and exhibited some dynamic modification around the surface of the metal oxide. Computational perturbations were considered to discuss the modification behavior in addition to the studied Li, Na, and K metals. Optimization of the three doping systems was achieved followed by generating DOS and electronic band structure maps. A dynamic simulation was performed with temperature over 2000 k: the presence of the metal on the surface and prediction of its ZrO2 inclusion leading to access adsorption behavior, besides generating predictive designed models described the adsorption affinity on the solid-state surface. It cannot be neglected the importance of various metals as a main role in chemotherapy. Molecular docking investigation was considered to predict the binding behavior of the studied metal ZrO2 carrier system as an anticancer agent. Also, docking affinity was helpful in comparing the active sites binding for the studied metals, resulting in a notable binding affinity for both Li- and Na-zirconia incorporation. Methods: The program PWSCF, which is a component of the quantum ESPRESSO suite for quantum simulation of materials, was used to construct geometric systems. The generalized gradient approximation in the Perdew-Burke-Ernzerhof (GGA/PBE) function with D3 correction (Becke-Jonson damping) was applied to the exchange-correlation energy. As the last step in the DFT postulation and design, adsorption locator annealing was carried out on the convergent models using the Materials Studio simulation package. The main roles played by metal atoms are in protein binding and the suppression of bio-active regions. For the docking process, the protein was produced using AutoDock 4.2 and Discovery Studio software in accordance with the usual methodology. Chimera and Discovery Studio were used to examine the docking data that was processed after generating specific grid box dimensions for 7BTN. [ABSTRACT FROM AUTHOR]

This work describes the implementation of a novel dynamic Arbitrary LagrangianEulerian (ALE) formulation for the simulation of pavement structures loaded by rolling tires in a finite element framework. The proposed formulation enables the simulation of dynamic effects like acceleration, deceleration and variation of the wheel load on the pavement. The ALE scheme is described for a hyperelastic St. Venant-Kirchhoff material capable of finite deformations. With the adoption of this dynamic ALE formulation, a significant improvement in terms of speed and efficiency of the simulation is achieved in comparison to a classical transient Lagrangian formulation. This is primarily because only the relevant portion of the mesh around the applied load needs to be discretized and simulated. Another benefit is that a cumbersome moving load formulation does not need to be implemented. The results show satisfactory agreement with a conventional Lagrangian simulation with a moving load. [ABSTRACT FROM AUTHOR]

There are two main approaches to modelling interfaces within nonequilibrium thermodynamics, the so-called sharp and diffuse interface models. Both of them are based on the local equilibrium assumption (LEA) in the bulk, but the latter additionally assumes the validity of this concept also within the interface itself (as the thermodynamic description is available and smoothly varying even within the interface), that is, on a finer length scale, which we call super-LEA. Instead of testing the two approaches against molecular dynamic simulations, we explore the mutual compatibility of these two descriptions of an interface in a nonequilibrium situation. Based on the level of detail in the two frameworks, one naturally cannot reconstruct a diffuse interface model from a sharp interface counterpart. One can test, however, whether diffuse interface models are indeed a more detailed description of the interface. Namely, assuming that both approaches are valid, we use the diffuse interface model (van der Waals entropy together with the Cahn--Hilliard type energy with the mass density as the order parameter) and its sharp interface counterpart (with the additional set of interfacial state variables sub jected to known thermodynamic constraints) to test their mutual compatibility and indirectly verify the correctness of the additional super-LEA of the diffuse models. That is, thanks to super-LEA, we define five interfacial temperatures that should be equal. However, when we analyze diffuse interface results like experimental or simulation data in terms of sharp interfaces, we show that, contrary to molecular simulation data, they do not yield equal interfacial temperatures. We argue that the culprit is the super-LEA which is most prominently expressed in the accessibility of the entropy density profile. Nevertheless, it is observed that there is an inconsistency between diffuse and sharp interface descriptions; they cannot both be correct. The sharp interface framework has been recently tested against molecular dynamics and the obtained results suggest that super-LEA is the potential weakness of the diffuse framework. In this sense, sharp interfaces are found to be superior to diffuse interfaces in their general ability to model physical systems with interfaces. [ABSTRACT FROM AUTHOR]

The polymorphism of Minodronic acid (MDA) monohydrates (form D and form E) was investigated in this work. The results revealed that the main difference lies in the discrepancy of hydrogen bonds in two polymorphisms. In addition, the atoms-in-molecules (AIM) analysis was conducted to assess the strength of hydrogen bonds. The hydrogen bonds in form D were estimated as electrostatic, while the corresponding hydrogen bonds in form E were partially covalent type. Then the polymorphic transformation mechanism was investigated by experiments coupled with molecular dynamic simulations. As the conformation of the water molecule transforms from Form D to Form E, the hydrogen bond interaction between water and MDA molecules gradually becomes stronger. The observations were consistent with the results obtained from molecular dynamic simulations. The energy barriers of the path I were in line with the simulation results. This indicates the reliability of the polymorphic transformation mechanism of the MDA monohydrates. [ABSTRACT FROM AUTHOR]

Potentilla nepalensis belongs to the Rosaceae family and has numerous therapeutic applications as potent plant-based medicine. Forty phytoconstituents (PCs) from the root and stem through n-hexane (NR and NS) and methanolic (MR and MS) extracts were identified in earlier studies. However, the PCs affecting human genes and their roles in the body have not previously been disclosed. In this study, we employed network pharmacology, molecular docking, molecular dynamics simulations (MDSs), and MMGBSA methodologies. The SMILES format of PCs from the PubChem was used as input to DIGEP-Pred, with 764 identified as the inducing genes. Their enrichment studies have shown inducing genes' gene ontology descriptions, involved pathways, associated diseases, and drugs. PPI networks constructed in String DB and network topological analyzing parameters performed in Cytoscape v3.10 revealed three therapeutic targets: TP53 from MS-, NR-, and NS-induced genes; HSPCB and Nf-kB1 from MR-induced genes. From 40 PCs, two PCs, 1b (MR) and 2a (MS), showed better binding scores (kcal/mol) with p53 protein of −8.6 and −8.0, and three PCs, 3a, (NR) 4a, and 4c (NS), with HSP protein of −9.6, −8.7, and −8.2. MDS and MMGBSA revealed these complexes are stable without higher deviations with better free energy values. Therapeutic targets identified in this study have a prominent role in numerous cancers. Thus, further investigations such as in vivo and in vitro studies should be carried out to find the molecular functions and interlaying mechanism of the identified therapeutic targets on numerous cancer cell lines in considering the PCs of P. nepalensis. [ABSTRACT FROM AUTHOR]

The bimolecular reaction between OH− and CH3F is not just a prototypical SN2 process, but it has three other product channels. Here, we develop an accurate full-dimensional potential energy surface (PES) based on 191 193 points calculated at the level CCSD(T)-F12a/aug-cc-pVTZ. A detailed dynamics and mechanism analysis was carried out on this potential energy surface using the quasi-classical trajectory approach. It is verified that the trajectories do not follow the minimum energy path (MEP), but directly dissociate to F− and CH3OH. In addition, a new transition state for proton exchange and a new product complex CH2F−⋯H2O for proton abstraction were discovered. The trajectories avoid the transition state or this complex, instead dissociate to H2O and CH2F− directly through the ridge regions of the minimum energy path before the transition state. These non-MEP dynamics become more pronounced at high collision energies. Detailed dynamic simulations provide new insights into the atomic-level mechanisms of the title reaction, thanks to the new chemically accurate PES, with the aid of machine learning. [ABSTRACT FROM AUTHOR]

The nose landing gear retractable system of a certain type of military aircraft as the research object was use to provide a technical reference for the test assessment and performance appraisal of weapons and equipment, and to study the dynamic characteristics of the nose landing gear retractable system during the take-off and landing process of the aircraft, the nose landing gear retractable. A landing gear three-dimensional simulation model of the virtual prototype was use to study the reliability and safety of the retractable system under the coupling action of aerodynamic load, gravity and actuator load through multi-body dynamics and finite element simulation analysis methods. The results show that the forces on each hinge point of the landing gear retractable system are reasonable, and its strength, stiffness, modal frequency and stability meet the relevant indicators. Through the simulation analysis of the landing gear, it provides an entry point and key focus for the subsequent assessment of weapons and equipment, and also provides a technical reference for the performance evaluation and parameter identification and optimization of the landing gear retractable and retractable system. [ABSTRACT FROM AUTHOR]

A mathematical model of a technical RF inductively coupled plasma is presented. Results of a numerical experiment are reported in which key parameters for a system with five coils and a coupled power of 60 kW at the generator frequency 1.76 MHz were assessed. The distributions of temperature, pressure, flow rate, and current and magnetic flux density are displayed. The numerical experiment presented was carried out using the Magnetic Fields, Laminar Flow, and Heat Transfer modules of COMSOL Multiphysics®. [ABSTRACT FROM AUTHOR]

The high toxicity of pesticides to the ecosystem and humans has made their removal from water urgent. However, the properties of the insecticide made it challenging to complete the removal process with high adsorption capacity and exceptional selectivity. Biocompatible porphyrin-based MOFs with good adsorption capacity make them the best choice for removing methomyl pesticides from wastewater due to their large surface area and high porosity. In this work, iron-porphyrin-based MOFs (Fe-TCPP), zinc-porphyrin-based MOFs (Zn-TCPP) and copper-porphyrin-based MOFs (Cu-TCPP) were synthesized and investigated to remove methomyl from water. Besides the characterization of porphyrin-based MOFs with PXRD, FTIR, and FESEM, Langmuir and Freundlich isotherm models were used to describe adsorption behavior. Fe-TCPP showed a higher adsorption capacity (Qm) than Zn-TCPP and Cu-TCPP, and the Qm values for Fe-TCPP, Zn-TCPP and Cu-TCPP equal 270.07 mg g−1, 190.97 mg g−1, and 175.95 mg g−1, respectively. Monte Carlo and molecular dynamic simulations were used to study the adsorption mechanism. The computational investigation indicates that the methomyl molecules are aggregated inside the MOF cavities and form hydrogen bonds between the methomyl pesticide and MOF structure. [ABSTRACT FROM AUTHOR]

Transient response of the pinch point is crucial to the evaluations of the recuperator efficiency. A reheat and recompression cycle dynamic simulation system for supercritical CO2 is built, and a transient segmented model is developed to explore the dynamic characteristics of the recuperators. The operating conditions including inlet mass flowrate, temperature and pressure of the low temperature recuperator (LTR) change dramatically with the withdraw-mass variation, which causes different response characteristics of the pinch point. The pinch point gradually transfers from the cold end to the hot end of the LTR as the mass flowrate decreases. The higher pinch-point temperature difference leads to lower heat exchanger effectiveness, and the internal pinch point greatly weakens the recuperator performance. A new prediction model is proposed to quickly determine the pinch point location and analyze the operating conditions prone to cause internal pinch point. The range of split ratio in which the internal pinch point exists in the LTR is obtained. The lower-limit of split ratio variation is sensitive to the high- and low-pressures, the isentropic efficiency of the compressor, and the outlet temperature of the precooler, while the upper-limit of split ratio is only related to the pressures of the recuperator. [ABSTRACT FROM AUTHOR]

The primary goal of the current study is to optimise crash box designs for automobiles. Machine learning (ML) techniques are used to build an intelligent and reliable ML framework. With the help of this framework, the crash box design can be optimised for crashworthiness analysis. The optimisation of the crash box design is resource‐intensive due to its intricate geometric design, use of a variety of materials, and extensive use of dynamic simulations to determine the ideal structural parameters through simulations. A reinforcement learning‐based (RL) optimization technique is developed for this reason. The crash box is built with nonlinear first‐order shear deformation shell elements to provide the necessary simulation data, and nonlinear elastoplastic material is used to model the dynamic impact process. The RL agents are tuned using finite element (FE) simulations and synthetic data generated by a generative adversarial network (GAN) to optimise and select the optimal model parameters for vehicle crashworthiness analysis. To estimate the correct model parameter required to fulfil specified crashworthiness metrics, the RL agent learns and optimises automatically. This method is effective in terms of resources and could be helpful in the early stages of vehicle development. [ABSTRACT FROM AUTHOR]

This paper presents a virtual generation method for the heterogeneous microstructure of asphalt mixtures. The coarse aggregates used in the digital asphalt mixture were derived from real aggregates captured by a three-dimensional (3D) laser scanner. Then, a rigid-body dynamic simulation framework was proposed to generate a stable skeletal structure composed of coarse aggregates similar to those formed by compaction. Furthermore, FAM and air voids were generated based on the generated aggregate skeleton and the assumption of equal thickness of FAM film. To prove the reliability of the model, the air voids of the digital asphalt mixture samples were verified by comparison with real specimens. The generated digital specimens were also applied to finite element method (FEM) simulations to predict the dynamic modulus of the asphalt mixture and the simulated results were in good agreement with the experimental results. The method can be applied to study the spatial distribution of asphalt mixture components, the movement pattern of aggregate particles during compaction and numerical simulations at the microscopic scale. [ABSTRACT FROM AUTHOR]

Percutaneous needle insertion constitutes a widely adopted technique for performing minimally invasive operations. Robot-assisted needle placement and virtual surgical training platforms have the potential to significantly improve the accuracy of these operations. For this, the development of mathematical models that provide a complete characterization of the underlying dynamics of medical needles is considered of paramount importance. In this paper, we develop two three-dimensional nonlinear rigid/flexible dynamic models of brachytherapy and local anaesthetic transperineal biopsy (LATP) needles. The proposed models relax the assumptions of previous investigations, quantify the vibrational behaviour and the rigid-body dynamics of medical needles and allow for real-time haptic and visual feedback information. Their accuracy and computational efficiency are assessed and validated using commercial software. The results show that, among the examined methods, the Rigid Finite Element Method provides the most accurate and numerically efficient solution for capturing the dynamics of flexible medical needles. [ABSTRACT FROM AUTHOR]

Nickel-coated multi-walled carbon nanotubes (Ni-MWCNTs), through combining the high tensile strength and Young's modulus of multi-walled carbon nanotubes with the good wetting characteristics of nanoscale nickel particle, substantially increase their dispersion and composite efficiency in composites. Therefore, Ni-MWCNTs are a promising nano-reinforcement to strengthen the tensile performances of ultra-high performance concrete (UHPC). This study investigated the effects of Ni-MWCNTs with different aspect ratios on the uniaxial tensile behaviors of UHPC and explored the underlaying modification mechanisms by molecular dynamics simulation and microstructural analysis. The results indicated that the presence of Ni-MWCNTs notably modifies the tensile performances of UHPC. Ni-MWCNTs with large aspect ratios are preferable for improving the tensile strength and toughness of UHPC. Adding 0.5 wt.% Ni-MWCNTs with an aspect ratio of 1000 can lead to a maximum increase of 31.9 and 46.4% in the tensile strength and toughness, respectively. While Ni-MWCNTs with small aspect ratios of 125/200 are more effective in enhancing the Young's modulus and Poisson's ratio of UHPC, the increase rate of which can reach 31–53 and 11–30%. Such modifications derive from the enhancement of the interfacial bonding ability between MWCNTs and matrix due to the presence of nanoscale nickel particle and the improvement of matrix compactness owing to the introduction of Ni-MWCNTs. Additionally, the Ni-MWCNTs' bridging/pull-out effects, enhanced by the existence of nanoscale nickel particle, can retard crack development and consume energy under tensile loading. [ABSTRACT FROM AUTHOR]

In the present work, an extensive verification and validation study is performed to evaluate the accuracy and credibility for computational fluid dynamic (CFD) simulations of the hydrodynamic responses of a semi-submersible floating offshore wind turbine (FOWT) platform under bichromatic waves and random waves. A dynamic mooring model is coupled with the CFD code to accurately simulate the mooring system. For the bichromatic wave cases, the surge, heave, and pitch response amplitude operators (RAOs) at wave frequencies, mean surge offset and mean surge force of the semi-submersible platform are investigated. The numerical uncertainties of the above metrics are quantified, which are primarily sourced from the discretization uncertainty. For the random wave cases, the surge, heave, and pitch power spectral density (PSD) sums in wave frequency range and low frequency range are validated against the experimental results. The numerical uncertainty derived from the bichromatic wave cases is applied in the validation of the random wave cases. The PSD sums in wave frequency range have achieved the validation within the validation uncertainty. Though the PSD sums in low-frequency range are under-predicted, the results with the utilization of the CFD code agree more with the experimental value than the results from mid-fidelity tools. [ABSTRACT FROM AUTHOR]

Size plays an important role on the deformation mechanism of nanopillars. With decreasing size, many FCC nanopillars exhibit dislocation starvation which is responsible for their high strength. However, many details about the dislocation starvation like how often it occurs, and how much is its contribution to the total plastic strain, are still elusive. Similarly, the size below which the dislocation starvation occurs is not clearly established. In this context, atomistic simulations have been performed on the compression of <110> Cu nanopillars with size (d) ranging from 5 to 21.5 nm. Molecular dynamics (MD) simulation results indicate that the nanopillars deform by the slip of extended dislocations and exhibit dislocation starvation mainly at small sizes (<20 nm). The frequency of the occurrence of dislocation starvation is highest in small-sized nanowires and it decreases with increasing size. Above the size of 20 nm, no dislocation starvation has been observed. Furthermore, we define the dislocation starvation strain and based on this, it has been shown that the contribution of the dislocation starvation to the total plastic strain decreases from 70% in small-sized nanopillars to below 5% in large-sized pillars. The present results suggest that dislocation starvation is a dominant phenomenon in small-sized nanopillars. [ABSTRACT FROM AUTHOR]

The tensile deformation behaviour of blended polyethylene (PE) was studied using molecular dynamic methods. The blended PE was modeled by blending linear chains with different molecular weights based on a united atom model. The mechanical response and microscopic conformational behaviours of blended PE were investigated at different strain rates and temperatures. The interatomic energy evolution displayed a similar trend to the stress–strain curve showing the stiffness of blended PE increase with a higher fraction of chain with high molecular weight. The microstructure metrics associated with free volume, orientation, entanglement and crystallisation were recorded as a function of strain in detail to obtain insight into the role of PE chains with different molecular weights for blended PE during deformation. The conformation evolution indicates that orientation and disentanglement are more noticeable in the short chain with low molecular weight in a blended PE system, while the long chain promotes the crystallisation of the initial chain structure. The chain entanglement evolution clearly shows some new flexion nodes created to entangle short chains again, implying that re-entanglement might exist during the tensile deformation. [ABSTRACT FROM AUTHOR]

Artificial neural networks have changed many fields by giving scientists a strong way to model complex phenomena. They are also becoming increasingly useful for solving various difficult scientific problems. Still, people keep trying to find faster and more accurate ways to simulate dynamic systems. This research explores the transformative capabilities of physics-informed neural networks, a specialized subset of artificial neural networks, in modeling complex dynamical systems with enhanced speed and accuracy. These networks incorporate known physical laws into the learning process, ensuring predictions remain consistent with fundamental principles, which is crucial when dealing with scientific phenomena. This study focuses on optimizing the application of this specialized network for simultaneous system dynamics simulations and learning time-varying parameters, particularly when the number of unknowns in the system matches the number of undetermined parameters. Additionally, we explore scenarios with a mismatch between parameters and equations, optimizing network architecture to enhance convergence speed, computational efficiency, and accuracy in learning the time-varying parameter. Our approach enhances the algorithm's performance and accuracy, ensuring optimal use of computational resources and yielding more precise results. Extensive experiments are conducted on four different dynamical systems: first-order irreversible chain reactions, biomass transfer, the Brusselsator model, and the Lotka-Volterra model, using synthetically generated data to validate our approach. Additionally, we apply our method to the susceptible-infected-recovered model, utilizing real-world COVID-19 data to learn the time-varying parameters of the pandemic's spread. A comprehensive comparison between the performance of our approach and fully connected deep neural networks is presented, evaluating both accuracy and computational efficiency in parameter identification and system dynamics capture. The results demonstrate that the physics-informed neural networks outperform fully connected deep neural networks in performance, especially with increased network depth, making them ideal for real-time complex system modeling. This underscores the physics-informed neural network's effectiveness in scientific modeling in scenarios with balanced unknowns and parameters. Furthermore, it provides a fast, accurate, and efficient alternative for analyzing dynamic systems. [ABSTRACT FROM AUTHOR]

One of the central problems in ecology is how to scale from small‐scale observations and experiments to large‐scale patterns and processes. One approach to such upscaling is to use dynamic simulation models, but their application to large scales relevant for management is limited by computational costs, and their outputs are difficult to analyse without a systematic strategy. Our general objective is to propose such a strategy. The idea is to approximate the dynamics of detailed simulation models through a set of states, external drivers, and transition matrices, and then use Markov chain and network analysis of the resulting transition matrices to gain insights into the dynamics of the underlying detailed model. We used the individual‐based model COIRON, which simulates the dynamics of semiarid grass steppes in Patagonia (Argentina) under alternative grazing management, as example. Our specific objectives are to identify pathways of degradation and rehabilitation, as well as critical grazing thresholds and early‐warning vegetation states to guide sustainable grazing management in these steppes. Our results indicate nonlinear effects of stocking rate and grazing season on steppe dynamics. Markov chain analysis suggests benefits of seasonal over continuous grazing at intermediate stocking rates, and network analysis of recovery and degradation trajectories shows that intermediate stocking rates maximize differences between grazing seasons. Finally, our analysis identified specific vegetation states as early warning signals that indicate a high risk of irreversible vegetation changes. Patagonian grass steppes should ideally be managed with multi‐paddock grazing at moderate stocking rates around 0.5 sheep ha−1. The transition matrices summarize the relevant key features of the detailed model for larger scales, and applying Markov and network theory provides a systematic strategy to analyse its dynamics to respond to biological questions, both are often difficult to obtain by direct analysis of the detailed model. [ABSTRACT FROM AUTHOR]

Pentablock terpolymers are potential candidates for the self-assembly of multicompartment nanostructures. In this work, Dissipative Particle Dynamic simulation is employed to investigate how the equilibrium aggregate structures of C3B3A6B3C3 pentablock terpolymers are affected by polymer–solvent interactions in a solution. Multicompartment structures, such as layered micelles, onion-like micelles, onion-like vesicles, unilamellar vesicles, and vesicle-in-vesicle structures, are observed. Vesicles are obtained when the two end C-blocks or the central A-block are hydrophilic. The solvent encapsulation ability and vesicle membrane permeability are assessed. The unilamellar vesicle shows higher encapsulation efficiency and lower membrane permeability compared with the onion-like vesicles. Additionally, the two vesicles show different responses to shear. While the cargo release rate of the onion-like vesicle is not affected by shear, shear results in a slowdown of the release rate for the unilamellar vesicle. The membrane thickness of the unilamellar vesicle can be adjusted using the length of the central A-blocks. Vesicles with thicker membranes hold cargo more effectively. [ABSTRACT FROM AUTHOR]

Static and dynamic fluid–structure interaction of a flexible plate behind a stationary cylinder in uniform flow is explored for a body-to-fluid mass ratio of 10. Steady flow-structure computations for Re = 150, based on the diameter of cylinder and free-stream speed, reveal four regimes with respect to increasing flexibility of the plate. The plate does not undergo any lateral deflection in regime 1 beyond which it undergoes a symmetry-breaking bifurcation causing it to spontaneously deflect laterally. The curvature is of the same sign along the entire length of plate in regime 2 while it changes sign along the plate in regime 3. The lateral deflection, however, is still maximum at the plate tip. The location of maximum deflection moves away from the plate tip in regime 4. The evolution of flow structures including the strength of various standing vortices, with flexibility, is studied. The role of reattachment of flow on the surface of the plate and the modification of the pressure distribution is explored. The critical Re, beyond which the splitter plate spontaneously achieves a deflected shape, decreases with increase in flexibility. It is estimated to be Re = 122.33 for the limiting case of an infinitely flexible plate. Computations for dynamic fluid–structure interaction reveal several regimes of lock-in with different natural vibration modes of the plate and related hysteresis. No lateral bias in the time-averaged deflection is found during lock-in; it occurs in the desynchronization regime that precedes the lock-in regime with second mode. For the mass ratio considered, the bias in the static and dynamic simulations start at the same flexibility. [ABSTRACT FROM AUTHOR]

The ongoing commercialization and installation of full‐scale membrane aerated biofilm reactors (MABRs) stimulate the increasing need to monitor biofilm development. Biofilm thickness in MABRs can be assessed indirectly by plotting the exhaust oxygen purity versus bulk ammonia concentration, defined here as the MABR fingerprint soft sensor. Dynamic simulations with diurnal flow variations of an MABR unit model were implemented over a broad range of biofilm thicknesses and influent conditions consisting of variable C/N ratios and applied ammonia fluxes to assess the utility of the MABR fingerprint. Results show that the continuously decreasing trend of the MABR fingerprint plot slopes can be employed as a useful signal for biofilm thickness control in nitrogen removal processes. This technique is useful in a wide range of influent conditions and is helpful for MABR operators and designers to arrange biofilm thickness control events efficiently and determine where in an overall treatment process the technique can be applied to control biofilm thickness and optimize process performance. Practitioner points: The linear relationship between exhaust oxygen purity and bulk ammonia concentration is defined as the MABR fingerprint plot.MABR fingerprint plots are generated for a given biofilm thickness with diurnal flow or short‐term loading variations implemented.Continuously decreasing trends of the MABR fingerprint plot slopes are useful signals for biofilm control in nitrogen removal.The MABR fingerprint is useful over a wide range of influent conditions regarding C/N ratios and applied ammonia fluxes.MABR practitioners can use the fingerprint plots to determine when biofilm control measures should be taken. [ABSTRACT FROM AUTHOR]

Significant advancements have been made in the domain of targeted anticancer therapy for the management of malignancies in recent times. VEGFR-2 is characterised by its pivotal involvement in angiogenesis and subsequent mechanisms that promote tumour cells survival. Herein, novel N-arylmethyl-aniline/chalcone hybrids 5a–5n were designed and synthesised as potential anticancer and VEGFR-2 inhibitors. The anticancer activity was evaluated at the NCI-USA, resulting in the identification of 10 remarkably potent molecules 5a–5j that were further subjected to the five-dose assays. Thereafter, they were explored for their VEGFR-2 inhibitory activity where 5e and 5h emerged as the most potent inhibitors. 5e and 5h induced apoptosis with cell cycle arrest at the SubG0-G1 phase within HCT-116 cells. Moreover, their impact on some key apoptotic genes was assessed, suggesting caspase-dependent apoptosis. Furthermore, molecular docking and molecular dynamics simulations were conducted to explore the binding modes and stability of the protein–ligand complexes. [ABSTRACT FROM AUTHOR]

This article presents a disturbance estimationbased event-triggered sliding mode control design for the linear time-invariant system without continuous monitoring. Comparing with traditional design methods, the proposed method here considers the influence of control input on the sliding model in the process of sliding model estimation. As a result, sliding mode control is only triggered at triggering instances, which reduces the amount of communication and lowers the frequency of controller updates in practice. With the obtained control law, the stability of the output trajectory is proved. Furthermore, continuous monitoring can be avoided in triggering condition evaluating. Zeno behavior is proved to be excluded for the proposed event-triggered control. Moreover, numerical examples show the effectiveness of the proposed strategies, which executed on both linear dynamic simulation and practical spring-mass-damper system. [ABSTRACT FROM AUTHOR]

γ-Aminobutyric acid aminotransferase (GABA-AT) is a pyridoxal 5′-phosphate (PLP)-dependent enzyme that degrades γ-aminobutyric (GABA) in the brain. GABA is an important inhibitory neurotransmitter that plays important neurological roles in the brain. Therefore, GABA-AT is an important drug target that regulates GABA levels. Novel and potent drug development to inhibit GABA-AT is still a very challenging task. In this study, we aimed to devise novel and potent inhibitors against GABA-AT using computer-aided drug design (CADD) tools. Since the crystal structure of human GABA-AT was not yet available, we utilized a homologous structure derived from our previously published paper. To identify highly potent compounds relative to vigabatrin, an FDA-approved drug against human GABA-AT, we developed a pharmacophore analysis protocol for 530,000 Korea Chemical Bank (KCB) compounds and selected the top 50 compounds for further screening. Preliminary biological analysis was carried out for these 50 compounds and 16 compounds were further assessed. Subsequently, molecular docking, molecular dynamics (MD) simulations, and binding free energy calculations were carried out. In the results, four predicted compounds, A07, B07, D08, and H08, were found to be highly potent and were further evaluated by a biological activity assay to confirm the results of the GABA-AT activity inhibition assay. [ABSTRACT FROM AUTHOR]

In the chemical and petrochemical industries, an azeotropic mixture of acetone/methanol/butanone/tert-butanol needs to be separated for high-purity products. Following a previous work in which an energy-saving process composed of two extractive dividing-wall columns (EDWCs) was developed for the quaternary system, this paper focuses on the issue of dynamic control for this process. Several control strategies in combined with temperature control, temperature-difference control and composition control are established to maintain the purity of all products in the face of disturbances in feed flow and feed composition. Dynamic simulations demonstrate that a conventional temperature control structure provides very poor control while a control strategy that used three-temperature-difference control for both EDWCs is the most effective. • An effective control strategy is proposed for two extractive dividing-wall columns process of quaternary azeotropic mixtures. • Multiple temperature differences controls are designed to control the process. • A variety of feed disturbances are used to test control strategies. [ABSTRACT FROM AUTHOR]

There are two approaches for simulating memory as well as learning in artificial intelligence; the functionalistic approach and the cognitive approach. The necessary condition to put the second approach into account is to provide a model of brain activity that contains a quite good congruence with observational facts such as mistakes and forgotten experiences. Given that human memory has a solid core that includes the components of our identity, our family and our hometown, the major and determinative events of our lives, and the countless repeated and accepted facts of our culture, the more we go to the peripheral spots the data becomes flimsier and more easily exposed to oblivion. It was essential to propose a model in which the topographical differences are quite distinguishable. In our proposed model, we have translated this topographical situation into quantities, which are attributed to the nodes. The result is an edge-weighted graph with massbased values on the nodes which demonstrates the importance of each atomic proposition, as a truth, for an intelligent being. Furthermore, it dynamically develops and modifies, and in successive phases, it changes the mass of the nodes and weight of the edges depending on gathered inputs from the environment. [ABSTRACT FROM AUTHOR]

Non-planar Polycrystalline Diamond Compact (PDC) cutters have been widely used in deep formations and have certain advantages in improving the rock-breaking efficiency. However, there are few studies on their rock-breaking mechanism, and most numerical cutting models do not consider the heterogeneity of rock. This paper introduced an innovative multi-ridge-curve-shaped (MRCS) cutter. A cutting model of heterogeneous granite is established based on the Voronoi tessellation method, the accuracy and reliability of rock cutting numerical model is verified by rock cutting experiment. The results illustrate that compared with cylindrical cutter and axe-shaped cutter, MRCS cutter has a rock-breaking effect similar to "ploughing" and "shoveling", with minor force and higher rock-breaking efficiency. And the mechanical specific energy (MSE), force and its fluctuation of MRCS cutter increase with the increase of back rake angle, while demonstrate a fluctuation with the increase of the number of ridges. The entire drillstring dynamic simulation results of three kinds of PDC bits illustrate that MRCS PDC bit has smaller fluctuation of weight on bit (WOB), weaker axial and lateral vibration strength during the drilling process, significantly improve the rate of penetrate (ROP) and save the drilling costs. The results of this study explore the rock-breaking mechanism of MRCS cutter and provide a theoretical basis for the structural optimization design of cutters in harder and abrasive heterogeneous formations. [ABSTRACT FROM AUTHOR]

Relative to isotropic organic solvent medium, the structure and conformation of a reactant molecule in an organized and confining medium are often different. In addition, because of the rigidity of the immediate environment, the reacting molecule have a little freedom to undergo large changes even upon gaining energy or modifications in the electronic structure. These alterations give rise to differences in the photochemistry of a molecular and supramolecular species. In this study, one such example is presented. α-Alkyl dibenzylketones upon excitation in isotropic solvents give products via Norrish type I and type II reactions that are independent of the chain length of the alkyl substituent. On the other hand, when these molecules are enclosed within an organic capsule of volume ~ 550 Å3, they give products that are strikingly dependent on the length of the α-alkyl substitution. These previously reported experimental observations are rationalized based on the structures generated by molecular modeling (docking and molecular dynamics (MD) simulations). It is shown that MD simulations that are utilized extensively in biologically important macromolecules can also be useful to understand the excited state behavior of reactive molecules that are part of supramolecular assemblies. These simulations can provide structural information of the reactant molecule and the surroundings complementing that with the one obtained from 1 and 2D NMR experiments. MD simulated structures of seven α-alkyl dibenzylketones encapsulated within the octa acid capsule provide a clear understanding of their unique behavior in this restricted medium. Because of the rigidity of the medium, these structures although generated in the ground state can rationalize the photochemical behavior of the molecules in the excited state. [ABSTRACT FROM AUTHOR]

Cohesive zone model has been used widely in fracture propagations, but few of them have considered strain rate, plastic strain, and variable damping together. In this paper, artificial compliance and spurious oscillation in bilinear cohesive law are investigated through dynamic simulations. Several constitutive laws and damage criteria used in bilinear cohesive law are presented first, and the properties in these constitutive laws are analyzed about deficiency of plastic strain, inherent discontinuity of constitutive law, and inherent discontinuity of force. Two damage evolution methods (effective separation method and damage factor method) are compared, and the latter one that strictly follows damage criterion and has no healing effect is a better choice for damage evolution. Numerical investigations are conducted to help select proper stiffness and to make sure artificial compliance in an acceptable range. Apart from strain rate and plastic strain, variable damping is considered into bilinear cohesive law, which can remove discontinuous force caused by constant damping at the start and end of bilinear cohesive law. One fixed delamination propagation and two free fracture propagation examples are used to verify the methodology proposed in this paper. From the simulation results, the methodology used in this paper removes spurious oscillation caused by constitutive law itself and enables correct force response, and variable damping reduces spurious oscillation. [ABSTRACT FROM AUTHOR]