A theoretical solution for analysis of tunnels below groundwater considering the hydraulic–mechanical coupling

An analytical solution for the analysis of tunnels below groundwater table in plane strain axisymmetric condition is presented. Seepage body force and secondary permeability of the rock mass due to the mechanical–hydraulic coupling are taken into account. The strain-softening behavior model and Hoek–Brown empirical strength criterion for the rock mass are used in the analysis. As the derived analytical equations do not have closed form solutions, a computer program has been prepared for solving the corresponding equations numerically and examining the analysis. It is shown that the tunnel stability depends on the seepage and the pore water pressure particularly in the case of high pore pressure gradient.     

Regioselective Synthesis of Phenols and Halophenols from Arylboronic Acids Using Solid Poly(N‐vinylpyrrolidone)/ Hydrogen Peroxide and Poly(4‐vinylpyridine)/Hydrogen Peroxide Complexes

Solid hydrogen peroxide complexes based on poly(N‐vinylpyrrolidone) and poly(4‐vinylpyridine) were prepared and used as solid hydroxylating reagents. These solid hydrogen peroxide equivalents are found to be much safer, convenient and efficient reagent systems for the ipso‐hydroxylation of arylboronic acids to the corresponding phenols in high yields at a faster rate. The versatility of the reagents has been further expanded for the one‐pot synthesis of halophenols. Density functional theory calculations were carried out on hydrogen peroxide complexes of N‐ethylpyrrolidone and 4‐ethylpyridine as models to get a better understanding of structure and behavior of hydrogen peroxide complexes of the polymers poly(N‐vinylpyrrolidone) and poly(4‐vinylpyridine) compared to aqueous hydrogen peroxide.     

Retrospect and Prospect: Nanoarchitectonics of Platinum-Group-Metal-Based Materials

Nanoarchitectonics, a concept encompassing nanoscale microstructures and atomic arrangements in materials, enables the precise modification of materials for desired applications by controlling their physical and chemical properties, as well as surface charge or energy. Particularly in metal materials, where surface reactions play a critical role, nanoarchitecture becomes the most influential factor affecting activity, selectivity, and stability. Focusing on platinum-group metals (PGMs) due to their inherently high efficiency in energy and environmental applications, this article provides a comprehensive review of synthetic methods for the morphological control of metal nanomaterials. The morphological control is classified into atomic arrangements in 0D, 1D, and 2D nanocrystals, as well as nanoporous structures, and the mechanisms of major reactions are covered in detail. Each chapter is supplemented with a table featuring several examples, facilitating the reader's understanding of the structural controls of PGMs. Finally, the article outlines future challenges in achieving novel metal nanoarchitecture. The hope is that this review provides valuable insights into the synthesis of PGM-based nanomaterials and serves as a guide for designing and synthesizing innovative metal nanostructures for diverse applications.     

Quantitative duplex real-time polymerase chain reaction assay with TaqMan probe detects and quantifies Crocodylus porosus in food chain and traditional medicines

Consumption and exploitation of crocodiles have been rampant for their exotic, nutritive and medicinal attributes. These depredations are alarming and although they have continued to be monitored by wildlife and conservation agencies, unlawful trading of crocodiles shows an increasing trend worldwide. Recently, conventional polymerase chain reaction (PCR) and PCR-restriction fragment length polymorphism (RFLP) assays for crocodile have been documented but they are only suitable for identification and cannot quantify adulterations. We described here a quantitative duplex real-time PCR assay with probes to quantify contributions from Crocodylus porosus materials simultaneously. A very short amplicon size of 127bp was used because longer targets could have been broken down in samples, bringing considerable uncertainty in molecular analysis. We have validated a TaqMan probe-based duplex real-time PCR (qPCR) assay for the detection of 0.004 ng DNA in pure state and 0.1% target meat in model chicken meatball. False negative detection was eliminated through an endogenous control (141-bp site of eukaryotic 18S rRNA). Analysis of 12 model chicken meatballs adulterated with C. porosus reflected 96.3?120.2% target recovery at 0.1?10% adulterations. A validation test of 21 commercial food and traditional medicine (TM) crocodile-based products showed 100% effectiveness. Short amplicon sizes, alternative complementary target, exceptional stability and superior sensitivity suggested the assay could be used for the identification and quantitative determination of C. porosus in any food or TM samples even under degraded conditions.     

Forecasting Mental Stress Using Machine Learning Algorithms

Depression is a crippling affliction and affects millions of individuals around the world. In general, the physicians screen patients for mental health disorders on a regular basis and treat patients in collaboration with psychologists and other mental health experts, which results in lower costs and improved patient outcomes. However, this strategy can necessitate a lot of buy-in from a large number of people, as well as additional training and logistical considerations. Thus, utilizing the machine learning algorithms, patients with depression based on information generally present in a medical file were analyzed and predicted. The methodology of this proposed study is divided into six parts: Proposed Research Architecture (PRA), Data Pre-processing Approach (DPA), Research Hypothesis Testing (RHT), Concentrated Algorithm Pipeline (CAP), Loss Optimization Stratagem (LOS), and Model Deployment Architecture (MDA). The Null Hypothesis and Alternative Hypothesis are applied to test the RHT. In addition, Ensemble Learning Approach (ELA) and Frequent Model Retraining (FMR) have been utilized for optimizing the loss function. Besides, the Features Importance Interpretation is also delineated in this research. These forecasts could help individuals connect with expert mental health specialists more quickly and easily. According to the findings, 71% of people with depression and 80% of those who do not have depression can be appropriately diagnosed. This study obtained 91% and 92% accuracy through the Random Forest (RF) and Extra Tree Classifier. But after applying the Receiver operating characteristic (ROC) curve, 79% accuracy was found on top of RF, 81% found on Extra Tree, and 82% recorded for the eXtreme Gradient Boosting (XGBoost) algorithm. Besides, several factors are identified in terms of predicting depression through statistical data analysis. Though the additional effort is needed to develop a more accurate model, this model can be adjustable in the healthcare sector for diagnosing depression.     

Control design approach for improved voltage stability in microgrid energy storage system

Microsystem Technologies - Nowadays, microgrid energy storage system is in great demand in order to compensate the demand-generation mismatch. In this study a new control design strategy is...     

Semiconductor Nanowire Light‐Emitting Diodes Grown on Metal: A Direction Toward Large‐Scale Fabrication of Nanowire Devices

Bottom‐up nanowires are attractive for realizing semiconductor devices with extreme heterostructures because strain relaxation through the nanowire sidewalls allows the combination of highly lattice mismatched materials without creating dislocations. The resulting nanowires are used to fabricate light‐emitting diodes (LEDs), lasers, solar cells, and sensors. However, expensive single crystalline substrates are commonly used as substrates for nanowire heterostructures as well as for epitaxial devices, which limits the manufacturability of nanowire devices. Here, nanowire LEDs directly grown and electrically integrated on metal are demonstrated. Optical and structural measurements reveal high‐quality, vertically aligned GaN nanowires on molybdenum and titanium films. Transmission electron microscopy confirms the composition variation in the polarization‐graded AlGaN nanowire LEDs. Blue to green electroluminescence is observed from InGaN quantum well active regions, while GaN active regions exhibit ultraviolet emission. These results demonstrate a pathway for large‐scale fabrication of solid state lighting and optoelectronics on metal foils or sheets.     

Plasmon-enhanced resonance Raman scattering and fluorescence in Langmuir-Blodgett monolayers

Localized surface plasmon resonances in silver and gold nanostructures are engaged to enhance the inelastic Raman scattering and the fluorescence of a phopholipid containing a sulforhodamine 101 acid chloride dye known as Texas Red. The most efficient coupling and enhancement are attained when the excitation laser line is in resonance with both the chromophore and the plasmon absorption of the nanostructure, the case of surface-enhanced resonance Raman scattering, allowing single-molecule detection. The tagged phospholipid was incorporated into a single fatty acid Langmuir monolayer at varying concentrations and transferred onto an evaporated Ag nanoparticle film. Surface-enhanced fluorescence is achieved using shell-isolated silica-coated gold nanoparticles, an emission enhancement named SHINEF.