Suitable Size Research Articles

Numerical analysis of fixed-end hollow rectangular beam under uniformly distributed load

The purpose of using opening in the reinforced concrete (RC) rectangular beam is the reduction of self-weight, cost, displacement, and strain. Therefore, this research performs linear elastic finite element analysis by using ETABS for fixed-ended RC hollow and solid rectangular beams under uniformly distributed loadings with variable beam lengths, compressive strengths, and opening sizes.The solid and hollow beams are considered to be a 2-nodded line element for the numerical analysis. The maximum range of validation result in case of hollow beam is found to be (3.9 to 7.9) %, which may indicate good accuracy of numerical analysis. The 50 × 50 mm opening size is suitable for 300 × 300 mm RC rectangular beam because of showing the positive normalized deflection of (0–1.45) % and lower strain rates (i.e. 0.13 % and 0.17 %) to compare the solid beam. This research may help professional engineers to use suitable opening size for design and construction works. Although, there is a scope to enhance this research in future by performing nonlinear analysis.

Tapered coreless optical fiber-based refractive index sensor for acetone concentration detection

A fast-response optical fiber sensor is designed and fabricated to detect different concentrations of volatile acetone. The proposed sensor structure was fabricated by splicing a segment of tapered coreless fiber (CLF) amid two single-mode fibers (SMF). Herein, tuned tapered diameters and lengths of CLF’s cladding were immersed in various concentrations of the acetone solutions to sense the effective refractive index (RI) variations. Accordingly, the sensor’s performance with tuned diameters at different lengths of the CLF was optimized to realize the suitable size of amplified evanescent fields. The sensor responded remarkably towards acetone concentrations, with a superior sensitivity of 336.102 nm/RIU, 0.163 nm/%, and 27.531 × 10−5 nm/ppm at 5 cm length and 60 µm taper diameter of CLF. The examined sensor possesses a fast response time with a minimum detection limit of 0.244 RIU, 5.025%vol, and 2.9 ppm. Though the rapid evaporation (volatility) of the acetone compound exempted it from air pollutants, many industrial and human body processes produce acetone which needs to be detected. The examined sensor may have the potential to detect in a non-invasive approach with high accuracy and rapid diabetes in humans, lung cancer, etc.

Development of a method for evaluating fabric surface contamination by particulate matter using fluorescent particles

Functional clothing products are being developed to prevent the attachment of particulate matter (PM). However, currently, PM-blocking performance of such products cannot be quantitatively evaluated. This study developed a method for measuring fabric surface contamination by PM by contaminating textile fabrics with PM and using an image processing technique. Silicate particles exhibiting fluorescence characteristics with a suitable size distribution were selected as PM simulants. The fabric surface contamination was calculated by contaminating textile fabrics under wind speed and PM concentration conditions similar to actual atmospheric environment. The number of pixels was obtained in the black and white binary images converted from the images of the textile fabrics captured under an ultraviolet (UV) light source. Experiments were performed using finished nylon fabric with PM-blocking performance and raw nylon fabric without PM-blocking performance. Comparison of the fabric surface contamination shows that it is possible to evaluate the PM-blocking performance of fabrics.

Silver Nanoparticles (AgNPs) Act as Nanoelicitors in Melissa officinalis to Enhance the Production of Some Important Phenolic Compounds and Essential Oils

ABSTRACTNanoparticles (NPs) are well‐known biostimulants in plant biotechnology, utilised to enhance the physical properties of plants and exhibit positive effects on them. The important key role is the most suitable type, effective dose and size of NP to be used in plant tissue culture systems. In this study, various concentrations of silver nanoparticles (AgNPs; 0, 25, 50, 75 and 100 μg L−1) were tested as elicitors in callus culture with the aim of enhancing secondary metabolite production in lemon balm (Melissa officinalis L.). According to the results obtained, callus formation rates have shown an increase in all applications compared to the control group. The highest callus formation, weight and diameter were observed in 50 μg L−1 application. In this application, the callus structure was compact and its colour was green. However, the aromatic compounds, neral and geranial increased significantly in 25 μg L−1 application. The maximum increase in phenolic compounds such as caffeic acid, chlorogenic acid, proto‐catechic acid, hesperidin and p‐coumaric acid was observed in the 75 μg L−1 AgNP and the highest increase in rosmarinic acid compound was determined in the 50 μg L−1 application. The study found that AgNP applications are an effective method for increasing the production of secondary metabolites in medicinal and aromatic plants, such as lemon balm, in vitro.

A superior Mn5CeTi5Ox catalysts for synergistic catalytic removal of chlorobenzene and NOx: Performance enhancement and mechanism studies

The transition metal titanium-doped Mn-Ce-Ox catalysts catalyst were employed to achieve synergetic removal of NO and CB at 180–220 °C. The Mn5CeTi5Ox catalyst with a molar ratio of Mn/Ce/Ti = 5:1:5 exhibits excellent activity, and the NOx and CB removal efficiencies reach 96 % and 89 % at 160–220 °C, respectively. The selectivity for N2 and CO2 are 93 % and 78 %, respectively. The N2-physisorption, NH3-TPD, H2-TPR and XPS results show that Ti doping makes the catalyst possess a mesoporous structure, suitable particle sizes, and excellent redox and Lewis site properties. All of these features contribute to the observed high NO and CB removal efficiency. The synergetic removal of CB and NO over Mn5CeTi5Ox results from the synergistic catalysis between the redox and the solid acid. On the one hand, in the synergistic removal process, CB and NH3 are competitively adsorbed on the catalyst surface, resulting in a decrease in the NH3-SCR activity. On the other hand, the removal of NO and CB has a synergetic effect. The byproduct NO2 produced by the NH3-SCR reaction promotes the oxidation of CB, which is beneficial for CB removal. Moreover, the consumption of NO2 indirectly promotes the NH3-SCR reaction, which partially compensates for the decrease in the NO removal efficiency caused by competitive adsorption between NH3 and CB. Ti doping promotes the participation of the SCR byproduct NO2 in the CBCO reaction and promotes the formation of maleic acid, an intermediate product of CB oxidation. In summary, the Mn5CeTi5Ox catalyst exhibits good activity for the synergistic removal of NOx and CB and is a promising candidate for the effective and economical removal of NO and CB during waste incineration.

Seismic Performance of Precast Drift-Hardening Concrete Walls Connected by Grout–Sheath Duct

In order to find a suitable size of sheath duct and a reliable construction method for precast walls, a cast-in-place and five 1/2 scale precast drift-hardening concrete walls reinforced with weakly bonded ultra-high strength SBPDN rebars were fabricated and tested under reserved lateral load and constant compression. The experimental variables were the diameter of sheath ducts (45 mm, 100 mm, and 120 mm), embedded length (20d and 35d; d is the nominal diameter of SBPDN rebars), axial load ratio (0.075 and 0.15), and the construction method. The experimental observations, hysteresis behaviors, envelope curves, residual deformation, crack propagation, and energy dissipation were compared in the study. Moreover, a formula was applied to calculate the bond strength of the sheath duct. The experimental and calculated results revealed that increasing the axial load ratio and embedment length could not enhance the bond strength of the sheath ducts, and increasing the diameter decreased the bond strength significantly. Anchored the SBPDN rebars in smaller sheath ducts separately was a more stable connection method for precast concrete shear walls and provided sufficient drift-hardening capability, even at a large drift level (over 3%).

Relationship Between Psychotherapy and Mitigation of Self-Stigmitization Among Adult Persons Living with HIV in Nairobi City, Kenya

Human Immunodeficiency virus (HIV) has caused a lot of suffering ever since the first case was reported. To date there are about 80,000,000 People living with HIV (PLWH). Although the rate of new infections has reduced, the effects remain far reaching, especially in Sub-Sahara Africa. Apprehension associated with HIV often scares many from finding out their HIV standing, considering restraint methods, avoiding risky conducts, and uplifting of PLWH endeavours. Many studies focused on HIV testing and counselling services which is for now mainly service provider driven. The drive of this study was showing the relationship between psychotherapy and mitigation of self-stigmatization (SS) among Adult PLWH in Embakasi East Sub-County (herein denoted Embakasi East), Nairobi City, County (herein denoted Nairobi City), Kenya; Social Cognitive Theory guided this study, employing descriptive research design on a target population of 3,886 PLWH registered for ART treatment at 7 public health centres in Embakasi East, Nairobi City. Cochran’s sample size formula was applied in determining the suitable sample size of 246 that was confirmed by the sampling table. Purposive sampling was used to select both the public health centres and the informants from each centre. Proportionate random sampling assisted in picking participants (both male and female), then random sampling was used to construct the sample. The sample of 246 (74 males and 172 females) was drawn, with 6 informants. Informants were interviewed and questionnaires completed by PLWH. In the analysis of the data, descriptive statistics, mainly frequencies, percentages and mean were applied on facts while thematic analysis on qualitative data. The study results showed that SS was very prevalent, caused by the respondents themselves and those around them. They acknowledged being hated, them hating themselves and did not want their HIV status known. Just a few had utilized psychotherapy service, who agreed that they were relieved a lot of pain they were undergoing, and they recommended it to others. The study recommended that authorities need to consider promoting and committing resources for psychotherapy as a solution to SS among PLWH, invest more in advocacy work, and invigorating sensitization among families on their role in supporting PLWH being

Electrically Conductive Nanomaterials: Transformative Applications in Biomedical Engineering - A Review.

In recent years, significant advancements in nanotechnology have improved the various disciplines of scientific fields. Nanomaterials, like, carbon-based (carbon nanotubes, graphene), metallic, metal oxides, conductive polymers, and 2D materials (MXenes) exhibit exceptional electrical conductivity, mechanical strength, flexibility, thermal property and chemical stability. These materials hold significant capability in transforming material science and biomedical engineering by enabling the creation of more efficient, miniaturized, and versatile devices. The indulgence of nanotechnology with conductive materials in biological fields promises a transformative innovation across various industries, from bioelectronics to environmental regulations. The conductivity of nanomaterials with a suitable size and shape exhibits unique characteristics, which provides a platform for realization in bioelectronics as biosensors, tissue engineering, wound healing, and drug delivery systems. It can be explored for state-of-the-art cardiac, skeletal, nerve, and bone scaffold fabrication while highlighting their proof-of-concept in the development of biosensing probes and medical imaging. This review paper highlights the significance and application of the conductive nanomaterials associated with conductivity and their contribution towards a new perspective in improving the healthcare system globally.&#xD.

Development of Web-Based Learning Media on Behavior Management to Enhance Activities of Daily Living for Children with Autism Spectrum Disorder

The aim of this project was to create an evidence-based learning media designed to address the behavior issues of children with Autism Spectrum Disorder (ASD) with activities of daily living. Composed of two phases, the first phase used eight school based occupational therapists identify the challenge with daily tasks and behavior management strategies for intervention. After the data was analyzed, the learning media was developed and reviewed by the therapists, content experts and 90 parents of autistic children. The web-based education consists of: 1) problems affecting the ADL performance of children with ASD: eating, tooth brushing, dressing, and sleeping divided between behavioral and sensory challenge and 2) behavior management strategies were identified to enhance the ADL performance of children with ASD and included sensory integration, environmental, and behavior modification. Parent perspectives revealed that the learning media were easily understandable and simple to use, with suitable font, size, and color of the text, as well as appropriate user interaction.

Short Spatiotemporal Fire History Explains the Occurrence of Beetles Favoured by Fire.

The number and area of forest fires in northern Europe have been dramatically reduced during the past century, and several fire-favoured species are now threatened. To promote the recovery of these species, prescribed burning is often used as a conservation measure, and to optimise the use of these conservation burns, knowledge is needed on suitable fire frequency, size and placement in the landscape. The aim of this study was to analyse the effect of recent fire history (12 yrs) on beetles sampled using smoke attraction traps at 21 forest sites in a 10,000 km2 region. We analysed the odds of finding a fire-favoured beetle species or individual among the beetles in each trap using a new spatiotemporal connectivity measure and compared the results to non-fire-favoured and saproxylic species. For fire-favoured beetles, both the number of species and individuals significantly increased with connectivity to previous fires, while the other two groups did not. The spatiotemporal connectivity that best explained the patterns suggests that fire-favoured beetles mainly respond to fires within a 2 km range up to 2-3 years after the fire. Hence, to preserve fire-favoured insects, prescribed fires must be close in space and time to other fires-whether prescribed or natural.

Vitamin D3 capsulation using maillard reaction complex of sodium caseinate and tragacanth gum

The encapsulation of vitamin D3 (VitD3) using the Maillard reaction complex of sodium caseinate-tragacanth gum (TG) to the production of water-soluble vitamins were studied. Spray drying was used to prepare the complex. Its physicochemical properties, stability, and release characteristics were evaluated. The results showed that containing sodium caseinate- Tragacanth gum (TG) 1 % (w/v) and VitD3 1 % (w/v) had the highest encapsulation efficiency (71 %). The resulting microcapsules showed suitable particle size, strong negative zeta potential, and good stability with spherical morphology. Thermal and spectroscopic analyses showed proper interaction between wall and core components. In vitro, release and simulated digestion studies demonstrated the ability of microcapsules to protect VitD3 under gastric conditions and provide controlled release in the intestine. This encapsulation system shows potential for enriching food with VitD3 and increasing its stability and bioavailability.

Study on the influence factors of the grain growth type of micro-nano silver powders prepared by liquid-phase reduction method

Abstract The preparation was carried out by liquid-phase reduction method with AgNO3 as the oxidizing agent, ascorbic acid (C6H8O6) as the reducing agent, and polyvinyl pyrrolidone (PVPK30) as the dispersing agent. The effects of silver nitrate concentration, ascorbic acid concentration, PVPK30 concentration, solution PH value before and after the reaction, and the temperature of reaction on average particle size (D50), dispersity, and particle size uniformity of silver particles were investigated by orthogonal experiment L18 (36) with six factors and three levels. The spheroid-like silver particles with good dispersity of 400-600nm and the spheroid-like silver particles with suitable particle size uniformity of 80-100nm were successfully prepared by optimal experiments. The results of the orthogonal experiment show that the molar ratio of the reducing agent to the oxidizing agent plays a decisive role in the type of grain growth. The crystal nucleus will coagulate and grow at a higher molar ratio (⩾1.05). With the increase in molar ratio, the nucleation rate is higher, the grain growth rate is faster, and the size of silver particles is smaller.

Highly-selective and temperature-compensated toluene sensor based on MOF-actuated optical WGM microresonator

This paper reports an optical fiber toluene sensor based on whispering gallery mode (WGM) microbottle resonator. The sensor includes a single-mode fiber (SMF)- no-core fiber (NCF)- SMF offset structure, which can be used as not only a coupler to couple light into the microbottle but also a multimode interferometer. The microbottle is formed by self-assembly of polydimethylsiloxane (PDMS) polymer doped with metal-organic framework (MOF) under the action of surface tension and gravity. The high specific surface area, suitable pore size, nitrogen-containing functional groups of MOF-Fe-PD and nonpolar groups on PDMS impart the high sensitivity and specific response of the sensor to toluene. When toluene is captured by the MOF and PDMS, the refractive index and volume of the cavity change, which affects the mode shift of WGM. According to test results, WGM of the sensor shows a linear sensitivity of 12.44pm/ppm with toluene concentration between 0 ppm and 337 ppm at room temperature, but it is affected by temperature crosstalk. While multimode interference dip is only sensitive to temperature, which can compensate for the mode shift of WGM caused by temperature change. Repeatability experiments show that the response and recovery time of the sensor are less than 70s. The method provides a toluene sensor with high selectivity, stable performance and simple preparation, which has potential environmental benefits and good industrial application prospects.

A 3D printing-based hybrid manufacturing method for high-strength polymeric medical implant fabrication

This paper presents a novel 3D printing-based hybrid manufacturing method to fabricate high-strength polymeric medical implants. Poly-ether-ether-ketone (PEEK) and polyether sulfone (PES) are blended to make filament for use with the fused filament fabrication technique to print custom designed implants. After printing and annealing, PES is removed by leaching to create interconnected porous PEEK structure with suitable pore size and porosity for bone tissue ingrowth. The proposed method provides a versatile approach to fabricating medical implants that are both mechanically strong and microstructurally inducive to osseointegration. The polymeric implants are also X-ray transparent to allow post-surgery evaluations using an imaging method. An intervertebral spacer implant example is used to demonstrate the proposed fabrication method.

Preparation and characterization of high performance super activated carbon based on coupled coal/sargassum precursors

High electrochemical performance supercapacitors require activated carbon with high specific surface area, suitable pore size distribution and surface properties, and high electrical conductivity as electrode materials, whereas there exists a trade-off relationship between specific surface area and electrical conductivity, which is not well met by a single type of carbon source. To solve this problem, the coal and sargassum are adopted to obtain the coupling product via co-thermal dissolution, followed by carbonization and KOH activation. The effects of mixing mass ratio and activation temperature on the prepared activated carbon (AC) are investigated using single factor experimental method. The experimental results show that AC1/3-800 has abundant micropore and mesopore content, good pore structure connectivity, high electrical conductivity and good wettability, and superior electrochemical properties compared with other activated carbons prepared in this experiment. Its total specific surface area is up to 2098.5 m2·g–1, the pore volume is up to 1.33 cm3·g–1, the content of mespores with diameter of 6–8 nm is significantly increased, and the pore size distribution is wide and uniform. When the current density increases from 0.1 A·g–1 to 10 A·g–1, the gravimetric capacitance decreases from 219 F·g–1 to 186 F·g–1 with a capacitance retention of 84.9%, the equivalent series resistance is very small, and the rate performance and reversibility of charging and discharging have also been excellent.

Defect-controlled confined growth of nano-MOFs to prepare materials with hierarchical micro/mesoporous structures for efficient CO2 capture

In recent years, nanoporous materials with special structure have been widely used in various fields. In view of the poor stability of MOFs materials and the poor mass transfer ability, in this study, we developed a simple method to restrict the growth of UiO-66-NH2 crystals in hollow silica by “vacuum evaporation” strategy, different kinds of acid regulators were introduced, to obtain a composite material with hierarchical pore structure. By characterizing the physical chemistry and microstructure of the composite adsorbent, and calculating the structural defects under different acid regulation, the adsorption and desorption performance and stability of the adsorbent for CO2 were comprehensively investigated. The mechanism of action on CO2 was further analyzed by in-situ infrared and other techniques. The results show that the change of coordination environment and coordination rate caused by the competition of organic acids, which increases the defects and reduces the nucleation and aggregation effect of UiO-66-NH2, promotes the formation of hierarchical pore structure of the composites. Among them, benzoic acid is the best regulating monocarboxylic acid, which makes UiO-66-NH2 have good dispersion in the cavity and suitable crystal size. The specific surface area of the composite material is 717.96 m2·g-1. At the same time, due to its excellent CO2 adsorption capacity (3.35mmol·g-1) at 298K and 1.06bar, it is 48.07% higher than the original UiO-66-NH2. In order to accomplish the goal of effective CO2 adsorption performance of composites, this study offers a novel approach for the synthesis and modification of MOFs-based composites.

Fine carbonyl iron particles grafted with poly(2-isopropenyl-2-oxazoline): A potential embolization agent for cancer therapy

Despite the significant success of clinical trials on cancer patients using the therapy with carbonyl iron (CI) particles, this topic laid dormant for over two decades. In this context, we developed a CI particle-based embolization agent via polymer surface engineering and tested its biocompatibility and behavior in contact with human blood. The finest grade of the CI particles was controllably grafted with poly(2-isopropenyl-2-oxazoline) (PiPOx) using surface-initiated atom transfer radical polymerization (ATRP) to achieve a system combining the properties of suitable size, high magnetization, and advantages at the cellular level connected to the presence of PiPOx. The cell viability of 3T3 fibroblasts and P388.D1 macrophages was investigated after treatment with particle extracts and was found to be concentration-dependent but generally demonstrated no or mild cytotoxicity. The PiPOx-grafted particles showed negligible effect on the breakdown of human erythrocytes and significantly improved hydrophilic-hemophilic properties when compared to bare CI. The magnetorheological (MR) activity of the particles dispersed in human blood was studied in vitro under shear mode conditions showing slightly decreased shear stresses but improved sedimentation stability. Moreover, the effect of PiPOx molecular weight on the studied parameters was monitored across the whole range of tests. The study demonstrates the potential of prepared core-shell structures in biomedical and related fields of application.

CT Morphometric Analysis of the Medial Femoral Condyle in an Indian Population: A Comparative Study of Unicompartmental Knee Arthroplasty Implants.

Purpose The objective of this study was to evaluate the compatibility of the medial femoral condyle (MFC) dimensions in the Indian population with the standard femoral components of three commercially available unicompartmental knee arthroplasty (UKA) implants. Methods This analytical study utilized CTmorphometric data from 100 consecutive non-arthritic adult knees. MFC dimensions were measured to assess their compatibility with UKA prostheses. The proportion of knees that could be optimally replaced using three commercially available UKA femoral implant systems, Link, DePuy, and Smith & Nephew, was calculated. Results The study cohort comprised 56 males and 44 females, with a mean age of 43.28 ± 10.53 years. For the Link implant system, the 'small' size was the most compatible, fitting 43% (43) of the patients, followed by 'medium-small' (35%, n = 35) and 'medium' (16%, n = 16). For the DePuy Sigma Uni implant, the best fit was 'size 1' for 38% (38) of the patients, followed by 'size 3' (25%, n = 25), 'size 4' (13%, n = 13), 'size 2' (10%, n = 10), and 'size 5' (2%, n = 2). In the case of the Smith & Nephew system, 'size 2' was the best fit for 30% (30) of the knees, followed by 'size 3' (27%, n = 27), 'size 4' (15%, n = 15), 'size 1' (12%, n = 12), and 'size 5' (8%, n = 8). Overhang of the femoral component, due to the MFC being smaller than the smallest available femoral component size, was observed in 6% (6) of knees with Link implants, 12% (12) with DePuy implants, and 8% (8) with Smith & Nephew implants. Conclusion The findings indicate that the most suitable femoral component sizes for Indian knees were 'small' in the Link system (43%, n = 43), 'size 1' in the DePuy system (38%, n = 38), and 'size 2' in the Smith & Nephew system (30%, n = 30). The results suggest a need for implant manufacturers to consider developing customized components tailored to the Indian population to enhance fit and minimize the occurrence of femoral component overhang.

Development of [formula omitted]/[formula omitted]/[formula omitted] discrimination with the phoswich detector using improved charge comparison method

Both pulse shape discrimination methods based on temporal difference characteristic and phoswich detectors are well-known and effective for particles discrimination, so the combination and further improvement are significant for better performance. In this paper, a phoswich detector combining YAG(Ce) and CsI(Tl) was constructed for α/β/γ discrimination using various techniques including two machine learning algorithms and an improved charge comparison method that further exploited the difference in the decay rate of pulse tail. The detector was designed with Geant4, simulating the suitable sizes of scintillators, and a high-speed digitizer was used for the collection of pulses that were from three radioactive sources. The results among the α (β) and γ rays had the figure of merit values greater than 2, simultaneously with an optimal 1.68 of the improved method that had more than twice the performance comparing the original 0.69 for α/β identification, which showed the detector is able to discriminate α, β and γ rays in mixed radiation field effectively.

Fabrication and application of highly permeable ceramic membranes: Membrane-forming mechanism, pore structure, separation performance and fouling mechanism analyses

High separation efficiency and satisfactory economic benefits are of great importance for ceramic membranes in the field of water treatment. Herein, microfiltration ceramic membrane with high permeability and selectivity was prepared in one-step (dip-coating and sintering) by sacrificial-interlayer method. The membrane-forming mechanism, effect of temperature on the morphology and pore structure, separation performance, fouling mechanism, and regeneration performance of the ceramic membranes were systematically investigated. The results show that membrane-forming mechanism of the membranes largely depends on film-coating filtration. The membrane with a mixture of nanocellulose crystals and graphene oxide as sacrificial interlayer (C1G1) and sintered at 1100–1300 °C possessed smooth surface. The open porosity and average pore size increased, and the pore size distribution became broader as the temperature increased. Moreover, the sacrificial-interlayer membrane sintered at 1300 °C (mA4S-C1G1) possessed suitable porosity (53.4%) and average pore size (200 nm), high permeance (4828 L·m−2·h−1·bar−1), which was larger than that of the membrane without sacrificial interlayer, manifesting that C1G1 could prevent the penetration of membrane-forming particles into support. The final fouling mechanism of mA4S-C1G1 was cake filtration, although complete pore blocking, standard pore blocking, intermediate pore blocking also involved in the initial stage. In addition, the oil rejection rate (∼97%) and steady-state feed flux (810–1154 L·m−2·h−1) of mA4S-C1G1 was high, and it also possessed good regeneration performance.