Increase In Rate Research Articles

Research on a Vibrationally Tuned Directional Seed Supply Method Based on ADAMS-EDEM Coupling and the Optimization of System Parameters

We have combined the theory of bulk dynamics and the agronomic requirements of precision sowing with the aim of resolving the technical problems of poor seed mobility and the difficulty in controlling suction posture, which leads to an increase in the leakage rate and a reduction in seed qualification index scores. In this study, a vibrationally tuned directional seed supply method and system are proposed. We carried out a force analysis of seeds, constructed kinematic equations for seeds and seed boxes to specify the state of the seed motion, and determined the structural parameters and the range of structural parameters that affect the seed suction posture. In addition, we coupled the ADAMS-EDEM simulation of the motion process of the seed and seed boxes and analyzed the vibrational tuning process of the seeds and the angle of inclination of the bottom surface of the seed box. The speed of the eccentric wheel and the eccentric distance were used as test factors. Three-factor and three-level Box–Behnken central combination testing with a single-grain rate, multiple-grain rate, and cavity rate were used as response indicators. Mathematical models were obtained between the experimental factors and the response indicators. Multi-objective optimization of mathematical regression models was carried out with Design-Expert 10.0.4 software. The optimal parameter combination obtained was a tilt angle of 14.27°, an eccentric wheel speed of 4.48 rad/s, and an eccentricity of 1.94 mm. The rate of single grains was 90.75%, the rate of multiple grains was 3.63%, and the rate of cavities was 5.62%. In bench performance tests, using an angle of inclination of 14°, the speed of the eccentric wheel was 4.50 rad/s and the eccentricity was 2 mm. The mean value of the single-grain rate was 89.28%, the mean value of the multiple-grain rate was 3.89%, and the mean value of the cavity rate was 6.83%. The test error was within permissible limits, and reliable results were achieved for parameter optimization. The results met the technical requirements for precision sowing. The results of the study can provide academic references for theoretical research on the methodology of posturing and directional seed supply. They can also provide ideas for the design and development of seed supply systems for precision sowing machinery.

Graphene promotes the growth of Vigna angularis by regulating the nitrogen metabolism and photosynthesis.

Graphene has promising applications in agriculture and forestry. In the current study, six different concentrations of graphene (0mg/L, 0.01mg/L, 0.10mg/L, 1.00mg/L, 10.00mg/L, and 100.00mg/L) were used to investigate its effect on the growth and development of V. angularis plants in soil culture. The results showed that the group treated with 1.00mg/L graphene (G-1) had significantly increased plant height (19.86%), stem diameter (24.33%), and leaf area (13.69%), compared to the control group (CK). Moreover, all concentrations of graphene had positive effects on the total root length, total root surface area, and the number of root tips of V. angularis. Compared to the CK group, the G-1 group had significantly increased leaf water potential (37.89%), leaf conductivity (2.25%), and SOD, POD, and CAT activities (47.67%, 35.22%, and 199.3%, respectively). The G-1 group also showed improved leaf net photosynthetic rate, chlorophyll content, and soluble sugar content (51.28%, 24.25%, and 38.35%, respectively), compared to the CK group. Additionally, 1.00mg/L graphene led to a 23.88% increase in the podding rate and a 17.04% increase in the yield of V. angularis plants. The rhizosphere soil of V. angularis treated with 1.00mg/L graphene had a 25.14% increase in hydrolyzable nitrogen content and a 66.67% increase in available phosphorus content. RNA-seq data indicated that 1.00mg/L graphene induced the expression of photosynthesis and nitrogen transmembrane transport genes, including ATP synthase subunit b, photosystem I reaction center subunit XI, photosystem I reaction center subunit IV A, ferredoxin, and psbP-like protein 1, as well as genes for photosynthesis antenna proteins, glutamine synthetase, glutamate dehydrogenase 1, cyanate hydratase, protein fluG-like, and NRT1/PTR family, suggesting that graphene promoted the growth and development of V. angularis by enhancing the photosynthesis and nitrogen metabolism processes in V. angularis plants. Our results indicated that a suitable concentration of graphene could significantly promote the growth of V. angularis plants in soil.

Intramolecular Catalytic Hydrogen Atom Transfer (CHAT).

Intramolecular catalysis (IntraCat) is the acceleration of a process at one site of a molecule catalyzed by a functional group in the same molecule; an external agent such as a solvent typically facilitates it. Here, we report a general first-principles-based IntraCat mechanism, which strictly occurs within a single molecule with no coreagent being involved─we call it intramolecular catalytic transfer of hydrogen atoms (CHAT). A reactive part of a molecule (chat catalyst moiety or chat agent, represented by -OOH, -COOH, -SH, -CH2OH, -HPO4, or another bifunctional H-donor/acceptor group) catalyzes an interconversion process, such as keto-enol or amino-imino tautomerization, and cyclization in the same molecule, while being regenerated in the process. It can thus be regarded as an intramolecular version of the intermolecular H atom transfer processes mediated by an external molecular catalyst, e.g., dihydrogen, water, or a carboxylic acid. Earlier, we proposed a general mechanistic systematization of intermolecular processes, illustrated in the simplest case of the H2-mediated reactions classified as dihydrogen catalysis [Asatryan, R.; et al. Catal. Rev.: Sci. Eng., 2014, 56, 403-475]. Following this systematization, the CHAT catalysis belongs to the category of relay transfer of H atoms, albeit in an intramolecular manner. A broader class of intramolecular processes includes all types of H-transfer reactions stimulated by an H-migration, which we call self-catalyzed H atom transfer (SC-HAT). The CHAT mechanism comprises a subset of SC-HAT in which the catalytic moiety is regenerated (i.e., acts as a true catalyst and not a reagent). We provide several characteristic examples of CHAT mechanism based on detailed analysis of the corresponding potential energy surfaces. All such cases showed a dramatically reduced activation barrier relative to the corresponding uncatalyzed H-transfer reactions. For example, we show that CHAT can facilitate long-range H-migration in larger molecules and can occur multiple times in one molecule with multiple interconverting groups. It also facilitates amino-imino tautomerization of unsaturated GABA-analogues and peptides, as well as intramolecular cyclization processes to form heterocycles, e.g., oxygenated rings. CHAT pathways may also explain the pH-dependent increase of mutarotation rate of glucose-6-phosphate demonstrated in pioneering experiments that introduced the classical IntraCat concept. In addition, we identify a ground electronic state CHAT pathway as an alternative to the UV-promoted long-range molecular crane keto-enol conversion with a remarkably low activation energy. To initially assess the possible impact of the new keto-enol conversion pathway on combustion of n-alkanes, we present a detailed kinetic analysis of isomerization and decomposition of pentane-2,4-ketohydroperoxide (2,4-KHP). The results are compared with key alternative reactions, including direct dissociation and Korcek channels (for which a new alkyl group migration channel is also identified), revealing the competitiveness of the CHAT pathway across a range of conditions. Taken together, this work provides insight into a general class of reaction pathways that has not previously being systematically considered and that may occur in a broad range of contexts from combustion to atmospheric chemistry to biochemistry.

Numerical simulation for radiative hybrid nanofluid (TiO2+Fe3O4∕H2O) flow due to a non-uniform stretching sheet with variable permeability

Variable permeability plays a crucial role in various manufacturing and technical applications such as fixed-bed catalytic reactors, heat exchangers, and dying, among others. The primary focus of this paper is to investigate the impacts of variable permeability on hybrid nanofluid (HNF) flow due to nonlinear sheet stretching with thermal heat flux. The HNF is made up of a mixer of [Formula: see text] and [Formula: see text] nanoparticles and water serving as the base fluid. Using efficient similarity transformations, the flow-governing equations are converted into a set of ordinary differential equations, and the resulting system is computationally solved by using the MATLAB program (bvp4c). The impact of various physical variables on the fluid velocity and heat transfer characteristics is analyzed via graphs. It is found that as the permeability parameter rises, the velocity of the HNF diminishes while the temperature amplifies. The drag force coefficient declines with an intensification of the volume fraction of the [Formula: see text] nanoparticles. The HNF [Formula: see text] exhibits 0.45–0.75% increase in heat transfer rate when compared to a nanofluid [Formula: see text] for different values of heat source parameter. The current investigation is compared to the existing literature, revealing a good level of agreement.

Exploring the Nexus between Women's Literacy Rates and Family Size: A Case Study of Nepal

The literacy rate of a nation serves as a pivotal indicator of its developmental trajectory across the globe . However, in many developing countries, including those in South Asia, a notable gender disparity persists in literacy rates, with women lagging behind men. This study focuses on Nepal, a representative country in this region, utilizing data spanning thr ee decades from the National Population Census (1991 to 2021). The findings reveal a considerable rise in women's literacy rates over the thr ee decade period, marking a noteworthy shift from the substantially low rates observed in 1991. The trend consisten tly ascended in subsequent years 2001, 2011, and 2021 indicating a positive trajectory in female literacy. Crucially, an intriguing relationship emerged between women's literacy rates and family size. Historically, when female literacy rates were considera bly lower, the national average family size tended to be higher. However, with the progressive increase in female literacy rates in recent y ears, a marked shift toward smaller, nuclear family sizes, averaging around four members, was observed. This shift i mplies that literate women exhibit heightened self awareness regarding family planning, influencing the move toward maintaining smaller nuclear families. Notably, while male literacy rates exceeded 50% even three decades prior, solely bolstering male liter acy did not correlate with maintaining nuclear family sizes. The study emphasizes the unique effectiveness of female literacy in shaping and mainta ining the transition toward smaller nuclear family structures. These findings underscore the critical role of women's education in influencing family planning and size, marking a pivotal factor in shaping societal structures and developmental paradigms.

Durability of Recycled Concrete after Reinforcing the Aggregates with Permeable Crystalline Materials

The utilization of recycled aggregate can significantly mitigate the extraction of natural sand and gravel. However, the practical application of recycled aggregate in engineering is impeded by its inherent characteristics, encompassing high water absorption, high crushing, and low apparent density. This study employed a soaking and air-drying method to enhance the strength of three types of aggregates with varying initial strengths by utilizing permeated crystalline materials. The durability of recycled aggregate concrete (RAC) was studied with three different aggregate replacement rates (0%, 50%, and 100%). The test results demonstrate that the slump, compressive strength, freeze resistance, and carbonation resistance of RAC exhibit a decreasing trend as the aggregate replacement rate increases. The freeze resistance and carbonation resistance of RAC are notably enhanced after incorporating permeated crystalline material. This study contributes to a sustainable and efficient solution for the treatment of construction waste, thereby enhancing the utilization rate of recycled concrete.

X-ray-Sensitive Doped CaF2-Based MRI Contrast Agents for Local Radiation Dose Measurement.

Ionizing radiation has become widely used in medicine, with application in diagnostic techniques, such as computed tomography (CT) and radiation therapy (RT), where X-rays are used to diagnose and treat tumors. The X-rays used in CT and, in particular, in RT can have harmful side effects; hence, an accurate determination of the delivered radiation dose is of utmost importance to minimize any damage to healthy tissues. For this, medical specialists mostly rely on theoretical predictions of the delivered dose or external measurements of the dose. To extend the practical use of ionizing radiation-based medical techniques, such as magnetic resonance imaging (MRI)-guided RT, a more precise measurement of the internal radiation dose internally is required. In this work, a novel approach is presented to measure dose in liquids for potential future in vivo applications. The strategy relies on MRI contrast agents (CAs) that provide a dose-sensitive signal. The demonstrated materials are (citrate-capped) CaF2 nanoparticles (NPs) doped with Eu3+ or Fe2+/Fe3+ ions. Free electrons generated by ionizing radiation allow the reduction of Eu3+, which produces a very small contrast in MRI, to Eu2+, which induces a strong contrast. Oxidative species generated by high-energy X-rays can be measured indirectly using Fe2+ because it oxidizes to Fe3+, increasing the contrast in MRI. Notably, in the results, a strong increase in the proton relaxation rates is observed for the Eu3+-doped NPs at 40 kV. At 6 MV, a significant increase in proton relaxation rates is observed using CaF2 NPs doped with Fe2+/Fe3+ after irradiation. The presented concept shows great promise for use in the clinic to measure in vivo local ionizing radiation dose, as these CAs can be intravenously injected in a saline solution.

Sex-specific differences in physiological parameters related to SARS-CoV-2 infections among a national cohort (COVI-GAPP study).

Considering sex as a biological variable in modern digital health solutions, we investigated sex-specific differences in the trajectory of four physiological parameters across a COVID-19 infection. A wearable medical device measured breathing rate, heart rate, heart rate variability, and wrist skin temperature in 1163 participants (mean age = 44.1 years, standard deviation [SD] = 5.6; 667 [57%] females). Participants reported daily symptoms and confounders in a complementary app. A machine learning algorithm retrospectively ingested daily biophysical parameters to detect COVID-19 infections. COVID-19 serology samples were collected from all participants at baseline and follow-up. We analysed potential sex-specific differences in physiology and antibody titres using multilevel modelling and t-tests. Over 1.5 million hours of physiological data were recorded. During the symptomatic period of infection, men demonstrated larger increases in skin temperature, breathing rate, and heart rate as well as larger decreases in heart rate variability than women. The COVID-19 infection detection algorithm performed similarly well for men and women. Our study belongs to the first research to provide evidence for differential physiological responses to COVID-19 between females and males, highlighting the potential of wearable technology to inform future precision medicine approaches.

The Effect of Laser Power on the Microstructure and Wear Resistance of a Ni3Al-Based Alloy Cladding Layer Deposited via Laser Cladding

A coating prepared via laser cladding has the advantages of a high-density reinforced layer, a low matrix dilution rate, and combination with matrix metallurgy. In this study, Ni3Al-based alloy cladding layers with Cr7C3 were prepared via laser cladding, and the corresponding microstructures and wear resistance were studied in detail. The results show that the Ni3Al-based cladding layer prepared using laser cladding technology had good metallurgical bonding with the matrix, and there were no pores, cracks, or other defects on the surface. The microstructures of the laser cladding layer were mainly γ′-Ni3Al, β′-NiAl, and in situ C7C3. As the laser power increased, the heat input increased, resulting in an increase in the dilution rate. Simultaneously, the carbide size in the laser cladding layer increased. With the increase in laser power, the hardness of the laser cladding layer of the Ni3Al-based alloy decreased, and the wear resistance of the laser cladding layer first strengthened and then weakened. When the laser power increased to 2.0 kW, the wear rate of the laser cladding layer decreased to 0.480 × 10−5 mm3/N·m. When the laser power increased to 2.4 kW, the wear rate of the laser cladding layer increased to 0.961 × 10−5 mm3/N·m, which was twice the rate at 2.0 kW. This could be attributed to small Cr7C3 particles, which could not effectively separate the wear pairs, resulting in more serious adhesive wear. Large Cr7C3 particles caused the surface of cast iron material with lower hardness to be damaged, which suffered more serious particle wear. The generation of short rod-shaped carbides should be avoided because, in the process of friction and wear, carbides with these shapes are easy to break, thus leading to crack initiation.

Correction of non-random mutational biases along a linear bacterial chromosome by the mismatch repair endonuclease NucS.

The linear chromosome of Streptomyces exhibits a highly compartmentalized structure with a conserved central region flanked by variable arms. As double strand break (DSB) repair mechanisms play a crucial role in shaping the genome plasticity of Streptomyces, we investigated the role of EndoMS/NucS, a recently characterized endonuclease involved in a non-canonical mismatch repair (MMR) mechanism in archaea and actinobacteria, that singularly corrects mismatches by creating a DSB. We showed that Streptomyces mutants lacking NucS display a marked colonial phenotype and a drastic increase in spontaneous mutation rate. In vitro biochemical assays revealed that NucS cooperates with the replication clamp to efficiently cleave G/T, G/G and T/T mismatched DNA by producing DSBs. These findings are consistent with the transition-shifted mutational spectrum observed in the mutant strains and reveal that NucS-dependent MMR specific task is to eliminate G/T mismatches generated by the DNA polymerase during replication. Interestingly, our data unveil a crescent-shaped distribution of the transition frequency from the replication origin towards the chromosomal ends, shedding light on a possible link between NucS-mediated DSBs and Streptomyces genome evolution.

Increase in acute pancreatitis, especially gallstone related, as the cause for emergency admissions: Temporal trend from Kashmir, India.

The incidence of acute pancreatitis is increasing globally. Gallstones (GS) and ascariasis are the major causes for acute pancreatitis in the Kashmiri population. In recent years, we have observed an increase in the admission rate of acute pancreatitis. Many patients who present first time as gallstone pancreatitis have asymptomatic gallstones. We aimed at studying the etiology and yearly admission rate of acute pancreatitis with main focus on gallstone pancreatitis and the contribution ofasymptomatic gallstones. This was a hospital-based, prospective, observational study from January 2015 to December 2019 for a period of fiveyears. Patients of acute pancreatitis were evaluated for etiology and yearly admission rate. Patients of gallstone pancreatitis were evaluated in terms of clinical profile, risk factors, nature (symptomatic/asymptomatic, known/unknown gallstones), size of stones, treatment and outcome in terms of severity and mortality. The data was analyzed by Statistical Package for the Social Sciences (SPSS) version 20.0, as mean (SD), frequencies and percentages. As many as 702 (8.5%) patients of acute pancreatitis were admitted among 8245gastrointestinal emergencies in fiveyears. The yearly admission rate of acute pancreatitis was 5.6%, 7.3%, 8.7%, 9.5% and 10.3%, respectively (p = 0.013). Gallstones, Ascariasis, alcohol and idiopathic acute pancreatitis were 47.7%, 6.9%, 1.2% and 33.7%, respectively. Gallstone pancreatitis increased from 31% in2015 to 52.4% in 2019 (p = 0.045) and ascariasis-related acute pancreatitis declined from 14.4% to 1.6% (p = 0.034). Asymptomatic gallstones constituted 87.7% of cases. Known/unknown asymptomatic gallstones and symptomatic gallstones were 24.4%, 63.2% and 12.2%, respectively. Gallstones < 5mm and > 5mm were76.1% and 23.8% respectively (p = 0.027). Cholecystectomy rate in index admission was 4.7%. Mild, moderate and severe gallstone pancreatitis was 60.2%, 18.8% and 20.8%, respectively. Mortality in gallstone pancreatitis was 10.4%. The incidence of acute pancreatitis is increasing due to gallstone pancreatitis. Ascariasis-related acute pancreatitis has declined. There is significant contribution of asymptomatic gallstones in patients who present for the first time as acute pancreatitis. Small gallstones < 5mm are likely to be the risk factors for gallstone pancreatitis.

Ulcer Bleeding in the United States: Epidemiology, Treatment Success, and Resource Utilization.

Peptic ulcer disease is the most frequent cause of upper gastrointestinal bleeding. We sought to establish the epidemiology and hemostasis success rate of the different treatment modalities in this setting. Retrospective cohort study using the National Inpatient Sample. Non-elective adult admissions with a principal diagnosis of ulcer bleeding were included. The primary outcome was endoscopic, radiologic and surgical hemostasis success rate. Secondary outcomes were patients' demographics, in-hospital mortality and resource utilization. On subgroup analysis, gastric and duodenal ulcers were studied separately. Confounders were adjusted for using multivariate regression analysis. A total of 136,425 admissions (55% gastric and 45% duodenal ulcers) were included. The mean patient age was 67years. The majority of patients were males, Caucasians, of lower income and high comorbidity burden. The endoscopic, radiological and surgical therapy and hemostasis success rates were 33.6, 1.4, 0.1, and 95.1%, 89.1 and 66.7%, respectively. The in-hospital mortality rate was 1.9% overall, but 2.4% after successful and 11.1% after failed endoscopic hemostasis, respectively. Duodenal ulcers were associated with lower adjusted odds of successful endoscopic hemostasis, but higher odds of early and multiple endoscopies, endoscopic therapy, overall and successful radiological therapy, in-hospital mortality, longer length of stay and higher total hospitalization charges and costs. The ulcer bleeding endoscopic hemostasis success rate is 95.1%. Rescue therapy is associated with lower hemostasis success and more than a ten-fold increase in mortality rate. Duodenal ulcers are associated with worse treatment outcomes and higher resource utilization compared with gastric ulcers.

EFEKTIVITAS PEMBERIAN SIMULASI HAND HYGIENE TERHADAP KEPATUHAN HAND HYGIENE PETUGAS NON MEDIS DI RUMAH SAKIT PKU MUHAMMADIYAH YOGYAKARTA UNIT II

Hospital Associated Infection (HAIs) is the world’s problem and one of the causes is hand hygiene compliance in healthcare workers are still low. Data showed 80% of HAIs spread by hands. Non medical healthcare workers are at risk for spreading the phatogen by hands, because although they don’t give intervention directly to the patients, they still have big possibilities to be in one of 5 moments hand hygiene. Hand hygiene simulation is one of training methods for heakthcare workers to create higher compliance in hand hygiene. This research was an experimental design with one group pre-posttest design. The population were all non medical healthcare workers in security department, nutritional department, and cleaning service department, the total sample is 37 persons. Paired T-test is used for stastitical analysis.The results obtained, the implementation of hand hygiene with proper procedure is 0,55%. The compliance rate increase after intervention by hand hygiene simulation 13,83%. Statistical analysis showed significant result p&lt;0,05; p=0,026 for security department, p=0,027 for nutritional department, and p=0,002 for cleaning service department, meaning there is a difference in hand hygiene compliance of non medical healthcare workers before and after intervention by hand hand hygiene simulation.Hand hygiene simulation is effecticve to improve hand hygiene compliance. Therefore it can be used to improve hand hygiene compliance in non medical healthcare workers.

Characteristics of systemic testosterone therapy for female hypoactive sexual desire disorder-a claims database analysis.

Testosterone therapy (TTh) is recommended for postmenopausal women with hypoactive sexual desire disorder (HSDD); however, there remain insufficient data to support use of TTh in premenopausal women with sexual dysfunction. In this study, we used a large national database to evaluate prescribing trends of TTh for women with HSDD. We conducted a cohort analysis of information from electronic health records acquired from the data network TriNetX Diamond. The study cohort consisted of women 18-70 years of age with a diagnosis of HSDD. We analyzed trends of testosterone prescriptions, routes of testosterone administration, and coadministration of testosterone with estrogen. Despite an increase in rates of testosterone prescriptions for HSDD, there remains a high degree of variability in the duration of treatment, route of administration, and coadministration of estrogen with significant underprescription of testosterone. Our query of the TriNetX database led to the identification of 33 418 women diagnosed with HSDD at a mean age of 44.2 ± 10.8years, among whom 850 (2.54%) women received a testosterone prescription. The testosterone prescriptions were highly variable with regard to duration and route of administration and coadministration with estrogen. For all patients until 2015, the prevalence of testosterone prescriptions for HSDD showed a positive quadratic relation was observed. Since 2015 a linear increase in prevalence was observed, with the highest rate of increase for patients aged 41-55years. The findings of this study reveal a significant need for further research investigating the optimal use of TTh to enhance the sexual health of women with HSDD, and further studies on the long-term effects of testosterone use must be undertaken to ensure that patients have access to safe and effective treatment. Limitations to this study include patient de-identification and lack of availability of testosterone dosage data. However, this study also has many strengths, including being the first, to our knowledge, to characterize the prescribing trends of testosterone for women with HSDD. Testosterone therapy should be considered as a potential therapy for premenopausal female patients with HSDD. Further studies on the long-term effects of testosterone use must be undertaken to address disparities in the management of HSDD and to ensure patients can access treatment.

Numerical Analysis of Water–Sediment Flow Fields within the Intake Structure of Pumping Station under Different Hydraulic Conditions

The vortices, backflow, and siltation caused by sediment-laden flow are detrimental to the safe and efficient operation of pumping stations. To explore the effects of water–sediment two-phase flow on the velocity field, vorticity field, and sediment distribution within intake structures, field tests and numerical simulations were conducted in this study with consideration for the sediment concentration, flow rate, and start-up combination. We applied a non-contact laser scanner and ultrasonic Doppler velocimetry to obtain the field data and reverse modeling of the three-dimensional model of the intake structure under siltation. A multiphase flow model based on the Euler–Euler approach combined with the k-ε turbulence model was adopted for numerical simulation under 10 working conditions, and the reliability was verified with field data. The results indicate that sediment promotes the evolution of coaxial vortices into larger-scale spiral vortices along the water depth, and the process of sediment deposition is controlled by the range, intensity, and flow velocity of the backflow zone. Furthermore, the maximum volume fraction of the near-bottom sediment increased by 202.01% compared to the initial state. The increase in flow rate exacerbates the turbulence of the flow field. Although the increase in sediment concentration benefits the flow diffusion, it further promotes sediment deposition. This study provides a new idea for modeling complex surfaces and considers different operating conditions. It can serve as a scientific reference for the structural optimization and anti-siltation design of similar water-conservancy projects.

Implementation of an Automatic Polishing Process with a Conveyor Mechanism

In the current industrial environment, products’ life cycles have become shorter and the need for more sophisticated molds with free-form surfaces has drastically increased. However, the polishing process of a product needs the exceptional skill of an experienced master. It is difficult to increase productivity if the manually operative process is not automated. So, the main objective of this project is to reduce manpower and time consumption of the polishing process in the industry. Which leads to increases in the productivity rate. This project deals with the automation of polishing work by the use of an industrial mechanical arm with a conveyor. Since polishing work, which takes much time, requires experience, patience, and skill, it is manually performed by skilled workers. This project aims at rationalizing such difficult polishing work by introducing a mechanical arm with conveyor and CAD technology. The arm can be equipped with a polishing tool, i.e., Buffing wheels, also known as mops, are either made from cotton or wool cloth and come bleached or unbleached. In addition, the project is to achieve a robust process that results in a consistent surface finish, the roughness of which can be specified and controlled.

Highly Permeable Ultrafiltration Membranes Based on Polyphenylene Sulfone with Cardo Fragments.

For the first time, copolymers of polyphenylene sulfone (PPSU) with cardo fragments of phenolphthalein (PP) were synthesized to develop highly permeable flat-sheet ultrafiltration membranes. By introducing cardo fragments into the polymer chain, we achieved a mechanical strength 1.3 times higher than the strength of commercial PPSU. It is shown that the introduction of the cardo monomer significantly increases the solubility of the polymer in aprotic solvents. The highest solubility is observed at the concentration of PP 50 mol.%. It is found that reduced viscosity of cardo polymer solutions leads to an increase in the coagulation rate. The permeance of asymmetric ultrafiltration membranes increases with PP concentration from 17.5 L/(m2·h·bar) (10 mol.% PP) to 85.2 L/(m2·h·bar) (90 mol.% PP). These data are in agreement with the results of a study of the coagulation rate of polymer solutions. Thus, for ultrafiltration membranes with 1.5-8 times higher permeance in comparison with PPSU due to the introduction of cardo fragments in the polymer chain, possessing high rejection of the model dye Blue Dextran (MW = 70,000 g/mol), more than 99.2%, as well as high strength characteristics, were achieved.

Alpha effect-driven enhancement of CO2 capture kinetics and size-controlled NaHCO3 crystals: Promoter-added NaOH absorbent study

In this study, the kinetics of the transition of Na2CO3 to NaHCO3 were enhanced based on the alpha effect by adding rate promoters to NaOH-based absorbents. Because the α-effect shows strong correlation with the electronegativity of the α-atom, to analyze their kinetic improvement, H2O2, NaOCl, and H3BO3 were selected as rate promoters. The promoters were chosen based on compounds with an O− or OH– group that can act as a Lewis base when CO2 acts as a Lewis acid or a structure that is easily accessible to CO2 molecules. Each promoter was added at different concentrations (0.05, 0.1, and 0.2 M), and the reaction rates of the absorbent solutions were experimentally evaluated. Among selected promoters, H2O2 exhibits the greatest effect, achieved the highest conversion efficiency, which showed an approximately 45-fold increase in reaction rate compared to the promoter-free NaOH solution. Furthermore, the enhancement in reaction rate allows the particle size to be controlled and precipitated with different crystalline structure. Therefore, the introduction of a promoter based on the α-effect not only significantly improves the reaction rate leading to NaHCO3 formation but also allows control of the crystal size and shape. This breakthrough can be a promising solution to address the limitations of conventional NaOH absorbents.

Effects of MHD and thermal radiation on non-Newtonian fluid with Cattaneo–Christov heat over a stretching flow surface

In this study, we are investigating the flow of an incompressible Williamson fluid using a Cattaneo–Christov heat flux model, with consideration for a magnetic Reynolds number that is not high. This fluid flows over a linearly stretched 2-D surface and is affected by a magnetic field, thermal radiation-diffusion, and heat generation. To model the Williamson flow, we apply a boundary layer approximation and develop the ordinary differential equations. The system of differential equations is transformed into a system of ordinary differential equations using a suitable transformation. We utilize the Iterative Runge–Kutta fourth-order scheme to numerically solve the boundary conditions associated with the nonlinear, dimensionless ordinary differential equations. Graphical representations of the results are employed to analyze the impact of physical properties on velocity, temperature, and concentration, with the numerical results presented in tabular form. Upon comparing our findings with previously published results, we have found them to be in good agreement. The velocity decreases as the Williamson fluid factor gradually increases. Williamson fluids are recognized for their shear thinning behavior, wherein viscosity decreases as the shear rate increases. However, higher parameter values can lead to increased fluid viscosity, potentially reducing the degree of shear thinning. This phenomenon results in a more uniform viscosity profile across varying shear rates, contributing to a reduced velocity distribution within the fluid.

Pulsatile pressure-driven non-Newtonian blood flow through a porous stenotic artery: A computational analysis

Blood flow through a narrowed artery, such as those caused by plaque buildup, can lead to various cardiovascular diseases. Therefore, studying this phenomenon is essential for developing better treatments and understanding the underlying mechanisms. In this study, a mathematical model is developed to simulate blood flow through stenotic arteries with porous walls. The familiar Navier-Stokes equations are executed to simulate flow, whereas the Carreau fluid model is employed to quantify blood rheology. This model illustrates both Newtonian and non-Newtonian characteristics depending on the shear rate. Other than that, the blood vessel is assumed to have a moderate level of stenosis with porous saturated walls. The solution of the governed partial differential equations is carried out using a finite difference scheme. Our research addresses the impacts of permeability and rheological parameters, stenosis size, Brinkman number, and Prandtl number on blood velocity, flow rate, resistance to flow, wall shear stress, and temperature distribution. The findings demonstrate that while flow resistance reduces, the velocity, shear stress, and flow rate increase with high permeability values. Conversely, as the stenosis amplitude increases, the magnitude of wall shear stresses, velocity, and flow rates decrease. In addition, blood rheology also has the potential to transfigure the aforementioned factors. We also found that the temperature distribution increases with the Brinkman number, stenosis size, permeability, and power law exponent. It drives down, however, by raising the values of Weissenberg number and Prandtl number. Collectively, our findings contribute to a better understanding of the complicated phenomena of blood flow in stenotic vessels with porous saturated walls. The findings of this study may be valuable in establishing improved therapies for cardiovascular disorders and formulating more precise mathematical models to forecast blood flow in vivo.