Increase In Diameter Research Articles

PERTUMBUHAN DAN PERKEMBANGAN TANAMAN SAMAMA (Anthocephalus macrophyllus) DALAM WAKTU X TAHUN DI DESA HATUSUA KECAMATAN KAIRATU KABUPATEN SERAM BAGIAN BARAT

The aim of this research is to determine the increase in diameter and increase in height of Samama plants (Anthocephalus macrophyllus) for one year after 10 years of measuring the relationship between soil pH and soil moisture with the growth rate of Samama plants (Anthocephalus macrophyllus) as well as environmental factors that influence the growth of Samama. This research uses a stepwise method by calculating the average annual increase (MAI), current annual increase (CAI), and multiple regression analysis. The results of further research showed that there was an increase in the diameter of the Samama plant (Anthocephalus marcophyllus) from 9 years to 10 years. It is known that the Current Annual Increase (CAI) of the tenth diameter is 1.0 (cm/plant/yr). And the average annual increment (MAI) in diameter is 2.82 (cm/plant/yr), the current annual increment (CAI) is high, namely 1.11 (cm/plant/yr) and the average annual increment (MAI) is high namely 2.74 (cm/plant/yr).

Retinal blood vessel diameter changes with 60-day head-down bedrest are unaffected by antioxidant nutritional cocktail.

Long-term human spaceflight can lead to cardiovascular deconditioning, but little is known about how weightlessness affects microcirculation. In this study, we examined how the retinal microvessels and cerebrovascular regulation of 19 healthy male participants responded to long-term head-down bedrest (HDBR), an earth-based analog for weightlessness. In addition, we examined whether an anti-inflammatory/antioxidant cocktail could prevent the vascular changes caused by HDBR. In all study participants, we found a decrease in retinal arteriolar diameter by HDBR day 8 and an increase in retinal venular diameter by HDBR day 16. Concurrently, blood pressure at the level of the middle cerebral artery and the cerebrovascular resistance index were higher during HDBR, while cerebral blood flow velocity was lower. None of these changes were reversed in participants receiving the anti-inflammatory/antioxidant cocktail, indicating that this cocktail was insufficient to restore the microvascular and cerebral blood flow changes induced by HDBR.

Synthesis of chitosan nanoparticles (CSNP): effect of CH-CH-TPP ratio on size and stability of NPs

In the face of a pressing global issue-the escalating threat of antibiotic resistance-the development of new antimicrobial agents is urgent. Nanotechnology, with its innovative approach, emerges as a promising solution to enhance the efficacy of these agents and combat the challenge of microbial resistance. Chitosan nanoparticles (CSNPs) stand out in biomedical applications, particularly in the controlled release of antibiotics, with their unique properties such as biocompatibility, stability, biodegradability, non-toxicity, and simple synthesis processes suitable for sensitive molecules. This study synthesized CSNPs using the ionotropic gelation method, with tripolyphosphate (TPP) as the crosslinking agent. Various CS: TPP ratios (6:1, 5:1, 4:1, 3:1, 2:1) were tested, and the resulting nanoparticles were evaluated using dynamic light scattering (DLS). The CS: TPP ratio of 4:1, with an average hydrodynamic diameter (DHP) of (195 ± 10) nm and a zeta potential of (51 ± 1) mV, was identified as the most suitable for further analysis. The characterization of NPs by Transmission Electron Microscope (TEM) and atomic force microscopy (AFM) revealed diameters of (65 ± 14) nm and (102 ± 18) nm, respectively. Notably, CSNPs exhibited significant aggregation during centrifugation and lyophilization, leading to diameter increases of up to 285% as measured by AFM. The antibacterial activity of CSNPs against Staphylococcus aureus and Escherichia coli was assessed using the resazurin assay. It was found that CSNPs not subjected to centrifugation, freezing, and lyophilization retained their antimicrobial activity. In contrast, those that underwent these processes lost their efficacy, likely due to aggregation and destabilization of the system. This study presents a straightforward and effective protocol for encapsulating sensitive active agents and synthesizing chitosan nanoparticles, a potential system with significant implications in the fight against antibiotic resistance.

Effects of Soil Compaction Stress Combined with Drought on Soil Pore Structure, Root System Development, and Maize Growth in Early Stage

Soil compaction is a major environmental stress to root development and plant growth. Meanwhile, drought always results in increasing soil mechanical impedance, which in turn aggravates soil compaction stress. In this study, a column experiment with three levels of compaction stress (low, moderate, and severe) and two levels of soil water content (well-watered and drought,) was established to investigate the effects of soil compaction combined with drought on soil pore structure, root development, and maize growth properties. The results showed that soil compaction combined with soil water stress significantly affected the characteristics of soil pore structure. With the increase in soil compaction, the porosity, larger pores (>500 μm), and maximum pore diameter significantly decreased (p < 0.05) regardless of soil water status. Additionally, both pore morphology and network parameters also deteriorated under soil compaction with drought conditions. Soil compaction substantially affected the root length, root volume, root surface area, and root average diameter in the whole profile (p < 0.05). Compared to well-watered conditions, the effects of soil compaction on root characteristics under drought conditions were more obvious, which indicated that appropriate soil water content could alleviate compaction stress. The aboveground biomass and plant height showed a consistent trend with root traits under soil compaction stress regardless of water status. A Pearson’s correlation analysis showed that there were significant correlations between most soil pore parameters and maize growth traits. In addition, soil compaction showed a significant effect on both stomatal conductance and transpiration rate while soil water showed a significant effect on SPAD (Soil Plant Analysis Development).

Arterial Stiffness as a New Predictor of Clinical Outcome in Patients with Polycythemia Vera

Background: Thrombotic adverse events and disease progression are crucial in Polycythemia Vera (PV), as it stands as the leading cause of mortality. The pulse wave velocity (PWV) is a valuable indicator of arterial aging and often plays a significant independent role in contributing to cardiovascular adverse events (CV-AEs). The aim of this study was to examine the relationship between PWV and critical vascular function parameters, with the goal of identifying new predictive factors of vascular damage and exploring a potential connection with disease progression. Methods: Non-invasive aortic stiffness was assessed through carotid–femoral PWV measurement. PWV was measured using the SphygmoCor device. History of arterial or venous thrombosis (TAEs) or other CV-AEs was collected at baseline. PWV measurements were repeated at baseline, at 6 and at 12 months. Results: The study involved 28 PV patients aged 27 to 77 years, with 57.1% being male. Fourteen patients (50%) reported a high-risk thrombotic score at diagnosis, and 60.7% had at least one comorbidity. Multivariable regression models showed that hemoglobin levels were independently associated with PWV (β: 0.68, SE 0.24, p < 0.01). During the follow-up period (median duration 21.3 months, range 6–33), a total of 13 events were documented. Specifically, two patients exhibited a loss of response to treatment, four patients presented an increase in spleen diameters, three patients displayed an escalation of systemic symptoms, and three patients had a clear progression to secondary myelofibrosis. PWV (per 1 m/s: OR 1.70, 95% CI 1.00–2.91, p = 0.047) and leukocyte count (per 1 × 103/μL: OR 1.47, 95% CI: 1.04–2.09, p = 0.043) were significant predictors of events, independently of waist circumference, blood pressure, treatment, and hematocrit. Conclusions: PWV has demonstrated its potential as an effective tool for monitoring PV patients. It stands as a clinical parameter that can predict the risk of progression in PV patients. Further investigation is essential to fully explore this potential. If successful, it could offer clinicians a valuable resource for effectively managing PV patients.

Experimental analysis on fiber diameter of spunbond nonwoven fabrics through Plackett–Burman and Box–Behnken designs and its impact on mechanical properties

AbstractThe COVID‐19 pandemic sparked a surge in demand for nonwoven protective materials, prompting a significant increase in nonwoven fabric production. To advance understanding, particularly in the Spunbond process, we conducted experiments to analyze the effects of various input parameters on fiber diameter, and mechanical tests to study how fiber diameter influences the mechanical properties of spunbond nonwoven fabrics. Employing Plackett–Burman design and Box–Behnken design with Minitab 18, we have examined different process parameters and study the cause‐and‐effect relationships between input parameters and the response. A set of experiments were carried out with nine varying parameters, including polymer melt index, initial polymer temperature, and air velocity. By regression modeling, we assessed the effects and interactions of these factors on fiber diameter. The Box–Behnken approach revealed that only three factors significantly influenced fiber diameter. Our analysis unveiled valuable insights for optimizing process parameters to achieve a target fiber diameter of 31.0 μm, crucial for enhancing nonwoven fabric production. Moreover, the results of the tensile property tests show that fiber diameter influence mechanical properties of nonwoven fabrics. As the fiber diameters increase, the mechanical properties of the nonwoven fabric are increased.Highlights Market research of textile industry, particularly of nonwoven sector. Identification of the parameters of the Spunbond process. Selection of Placket–Burman and Box–Behnken designs to analyze, optimize, and predict fiber diameter. Evaluation of the designs results (analysis of variance, Pareto, Regression model …), determination of the optimal conditions and the factors that has most effect on fiber diameter. Investigation of the effect of fiber diameter on mechanical properties.

Experimental and analytical assessment of the bending behaviour of floating inflated membrane beams

The study aims to study the bending and failure behaviour of the inflated membrane beams under floating conditions to support their application in floating platforms. Bending tests are conducted to assess the structural stiffness and ultimate bearing capacity of the beam with various diameters and inflated pressures. With the elastic modulus determined through four-point bending tests, a new analytical formula based on Winkler elastic foundation theory is then developed to predict the deflection of the beams. The results revealed that the beams initially undergo total submersion, followed by end turn-up and anti-arching deformation in the loaded section. The bearing capacity of the beams increases with the increase in internal pressure and diameter. Localised wrinkling is a typical failure mode at low internal pressures, while at high pressures, the failure mode shifts to boundary failure, characterised by submerging in water. The experimental and analytical results show quite good agreement, confirming the accuracy of the current analysis. Overall, this paper contributes to understanding the bending and failure behaviour of inflated membrane beams under floating conditions and supports the offshore structure safety design.

Abstract 4125938: Novel Surgical Model of Thoracic Aortic Aneurysm Mediated by Vasa Vasorum Inhibition

Objective: The adventitial layer of the aorta contains the network of microvessels known as vasa vasorum. Previous work by our team revealed deficient vasa vasorum associated with medial hypoxia and upregulated adventitial thrombospondin-1 (TSP-1), an anti-angiogenic molecule, in human aortic aneurysm. We hypothesize that heightened TSP-1 in the ascending thoracic aorta induces aneurysmal degeneration through its anti-angiogenic effects on the vasa vasorum. We tested this hypothesis in a rabbit model via peri-adventitial delivery of ABT-510, a thrombospondin peptide mimetic. Methods: The ascending aorta was exposed in New Zealand White rabbits (n=16) and treated with ABT-510 proximally and a vehicle control distally. Echocardiography was undertaken immediately prior to the procedure and 14 days post-operatively. Adventitial vasa vasorum were quantified from H&E-stained sections. Elastin and collagen organization were assessed with Verhoeff-Van Gieson (VVG) and pentachrome staining as well as multiphoton microscopy. Immunodetection of Hypoxyprobe™ and alpha smooth muscle actin (αSMA) were also undertaken to identify hypoxia and smooth muscle cell content, respectively. Results: Echocardiography revealed an increase in aortic diameter over 14 days with ABT-510 treatment compared with control (42.27% ± 5.54 vs 20.99% ± 4.10, p=0.004). Histological analysis showed decreased vasa vasorum count (44.7 ± 9.19 vs 85.8 ± 12.89, p=0.048) and decreased vasa vasorum indexed cumulative area (0.013 ± 0.0037 vs 0.021 ± 0.0050 µm 2 / µm 2 adventitial area, p=0.019). Immunodetection of Hypoxyprobe™ showed evidence of increased hypoxia. VVG, pentachrome, and immunodetection of αSMA showed decreased elastin content, increased deposition of ground substance, and areas of smooth muscle cell loss . Multiphoton microscopy demonstrated fragmented elastin fiber microarchitecture and decreased collagen content (Fig 1). Conclusions: Our study findings demonstrate a novel, clinically relevant model for thoracic aortic aneurysm through vasa vasorum inhibition that recapitulates features of cystic medial degeneration. This translational model could enable development of targeted, pro-regenerative therapies that restore perfusion to the aortic wall.

Abstract 4139169: Treatment with methotrexate associated with LDL-like nanoparticles prevents the development of left ventricular fibrosis in a spontaneously hypertensive rat model

Introduction: Systemic arterial hypertension (SAH) can lead to left ventricle (LV) fibrosis and ventricular dysfunction. Methotrexate (MTX) associated with lipid nanoparticles (LDE) increases the cellular uptake of MTX by ninety-fold, which leads to therapeutic efficacy and reduces drug toxicity. Previously, treatment of rats with myocardial infarction with LDE-MTX decreased LV fibrosis and prevented ventricular dysfunction. The aim was to test LDE-MTX to preclude the development of cardiac damages caused by hypertension in spontaneously hypertensive rats (SHR). Methods: Twenty-four male rats with six-week-old were allocated in 3 groups: Control (CT): Wistar-Kyoto rats injected with saline; SHR: treated with LDE only and SHR-LDE-MTX: treated with LDE-MTX (1mg/Kg/week, I.P.). After 20 weeks of treatment, echocardiography, morphometry and protein expression were performed in the LV. The data were analyzed by ANOVA with Turkey’s post-test or Kruskal-Wallis test with Dunn's post-test. Linear regression was used to evaluate potential relationships. Results: Compared to CT, the two SHR groups showed dilation (increase in systolic and diastolic diameter); hypertrophy (increased thickness of the posterior wall) and systolic dysfunction (decreased ejection and shortening fractions). Furthermore, the SHR group showed increased LV fibrosis in both the interstitial region and the papillary muscle, possibly resulting from increased of type I collagen content. Treatment of SHR with LDE-MTX had no effect on LV dilation, hypertrophy or systolic dysfunction. However, LDE-MTX decreased LV fibrosis of the interstitial region and the papillary muscle. In addition, LDE-MTX increased the expression of MMP-2, and increased the bioavailability of intracellular adenosine, via increased expression of the adenosine A3 receptor. There was a negative correlation between the expression of the adenosine A3 receptor with interstitial fibrosis (r2=-0.31, p=0.03) and papillary muscle (r2=-0.47, p=0.03), indicating that the increased bioavailability of intracellular adenosine also contributed to the decrease in LV fibrosis in SHR. Conclusion: In SHR, treatment with LDE-MTX reduced LV fibrosis, possibly by modulating MMP-2 expression and increasing the bioavailability of intracellular adenosine, via the adenosine A3 receptor. These results suggest a therapeutic role for LDE-MTX in patients with LV fibrosis and heart failure caused by SAH, to be explored in future clinical studies.

Abstract 4144548: High Morbidity and Mortality in Adults With Turner Syndrome and Aortic Dilation: A Retrospective Cohort Study from the Healthy Heart Project

Introduction: Turner syndrome (TS) is caused by the partial or complete absence of one sex chromosome and affects 1 in 2500 liveborn infants. Hypertension, bicuspid aortic valve (BAV), and thoracic aortic aneurysms (TAAs) are more prevalent in TS compared to the general population and predispose to aortic dissections, which may occur in young adults with TS. We hypothesize that adults with TS who have TAAs experience a high rate of adverse cardiovascular outcomes. Methods: Adults with TS who had Healthy Heart Project (HHP) echocardiograms at national conferences between 2003 and 2023 were contacted for enrollment in descending order of the aortic size index (ASI, cm/m 2 ), defined as the ratio of the maximum ascending aortic diameter to body surface area. After informed consent, clinical characteristics and outcomes (as numbers of participants or median and interquartile range) were abstracted from questionnaires and medical records. Results: Sixty-four of 704 total HHP participants were contacted and 19 (with 10 of the 20 highest ASI values) were enrolled with complete data. The baseline ASI was 2.19 (0.48), compared to 1.51 (0.36) for all other HHP participants. The median age was 59 (13) years. The most prevalent characteristics were 45,X (10) or 45,X/46,XX (6) karyotypes; BAV (9), coarctation (4), or no congenital lesions (6); and hypertension (12). A mean of 10 serial aortic images were available for each participant over a follow up period of 14 (9.8) years. The median increase in aortic diameter was 0.09 (0.29) mm/yr at the sinuses of Valsalva and 0.26 (0.44) mm/yr at the ascending aorta. Seven participants underwent aortic operations due to enlarging TAAs when the median ascending diameter was 3.83 (0.67) cm (ASI 2.58 (0.11) cm/m 2 ). In 3 cases, operations were urgent due to cardiovascular symptoms or rapid aortic dilation, but there were no acute aortic dissections. The median time between the index image and subsequent repair was 3.5 (7.0) years. Three HHP participants with the 8th, 15th, and 42nd largest ASI values died prior to follow up. One death was caused by complications after surgical aortic valve replacement at age 20. Conclusions: In a cohort of adults with TS and TAAs, 40% (7/19) developed progressive aortic enlargement requiring aortic repairs and there were 3 deaths. These observations underscore the importance of lifelong surveillance and timely intervention to prevent deaths due to cardiovascular disease in TS.

Study on the Effect of Heat Transfer Characteristics of Energy Piles

The thermal performance of energy piles equipped with new metal fins to improve heat transmission is examined in this research. The solid heat transfer module of COMSOL Multiphysics was used to create a 2D numerical model of the energy pile, utilizing the energy pile at a field test site in Nanjing as an example. By contrasting the experimental data, the COMSOL Multiphysics model’s correctness was confirmed. After that, a new kind of energy pile fin was created to improve the heat transfer of the pile. The impact of the new fin type on the energy pile’s heat transfer efficiency was assessed, and the temperature change within the soil surrounding the pile before and after the fin was set was examined by contrasting the parameters of pipe configuration, buried pipe depth, and concrete thermal conductivity. The results indicate that after setting the fins to run for 336 h, the temperature of the concrete area increases by 10.8% to 12.3%, and the temperature of the region surrounding the pile increases by 5.3% to 8.7% when the tube diameter is chosen to be between 20 and 40 mm; The fins maximize the heat transfer temperature between the surrounding soil and the concrete, and as the tube diameter increases, the temperature drops. For 336 h of pile operation, the temperature of the concrete may be raised by 10.8% to 12.3% after the fins are set, and the temperature around the pile can be raised by 5.3% to 8.7%. The heat transmission efficiency of the energy pile can be improved by raising the temperature of the soil surrounding the pile through an increase in the concrete’s thermal conductivity; however, the degree of improvement diminishes as the conductivity rises. It is intended that this study will offer insightful information on the best way to design energy pile heat transfer efficiency.

Enhanced Vasoconstriction in Sickle Cell Disease is Dependent on ETA Receptor Activation.

Sickle Cell Disease (SCD) carries a significant risk for poor vascular health and vascular dysfunction. High levels of vascular reactive oxygen species (ROS) as well as elevated plasma endothelin-1 (ET-1), a potent vasoconstrictor with actions via the ETA receptor, are both common phenotypes in SCD. Alpha-1 adrenergic receptor activation is a major mediator of stress-induced vasoconstriction. However, the mechanism of the SCD enhanced vasoconstrictive response is unknown. We hypothesized that SCD induces enhanced alpha-1 adrenergic mediated vasoconstriction through the ET-1/ETA receptor pathway in arterial tissues. Utilizing humanized SCD (HbSS) and genetic control (HbAA) mice, alpha-1a, but not alpha-1b or alpha-1d, receptor expression was significantly greater in aortic tissue from HbSS mice compared to HbAA mice. Significantly enhanced vasoconstriction in aortic and carotid arterial segments were observed from HbSS mice compared to HbAA mice. Treatment with ambrisentan, a selective ETA receptor antagonist, and a ROS scavenger normalized the aortic vasoconstrictive response in HbSS mice. In a randomized translational study, patients with SCD were treated with placebo or ambrisentan for 3 months, with the treatment group showing an increase in the percent brachial arterial diameter. Taken together, these data suggest that the ETA receptor pathway interaction with the adrenergic receptor pathway contributes to enhanced aortic vasoconstriction in SCD. Findings indicate the potential of ETA antagonism as a therapeutic avenue for improving vascular health in SCD.

Analysis of the screw pile group subjected to combined V–H loading for energy application

ABSTRACT The present study investigates the behaviour of screw piles in very stiff clay under the combined vertical and horizontal loads using a three-dimensional finite element analysis. The soil is modelled using the Mohr–Coulomb elastic, perfectly plastic material, whereas the pile shaft and helices are modelled as a linear elastic material. This study examines the effect of the number of helices, helix diameter, inter-helix spacing, and pile spacing on the performance of screw piles under both vertical compression and lateral loads. The study shows that the effect of the number of helices is negligible under the combined load. The increase in the helix diameter (D h) improves the pile performance. The results also reveal that the optimum interhelix spacing is 3D h, and the optimum pile spacing is 2D h. Thus, the present study demonstrates that optimizing the geometry of the screw pile enhances its performance, making it suitable for offshore wind turbines.

Effect of different running protocols on bone morphology and microarchitecture of the forelimbs in a male Wistar rat model.

It is accepted that the metabolic response of bone tissue depends on the intensity of the mechanical loads, but also on the type and frequency of stress applied to it. Physical exercise such as running involves stresses which, under certain conditions, have been shown to have the best osteogenic effects. However, at high intensity, it can be deleterious for bone tissue. Consequently, there is no clear consensus as to which running modality would have the best osteogenic effects. Our objective was to compare the effects of three running modalities on morphological and micro-architectural parameters on forelimb bones. Forty male Wistar rats were randomly divided into four groups: high intensity interval training (HIIT), continuous running, combined running ((alternating HIIT and continuous modalities) and sedentary (control). The morphometry, trabecular microarchitecture and cortical porosity of the ulna, radius and humerus were analyzed using micro-tomography. All three running modalities resulted in bone adaptation, with an increase in the diaphyseal diameter of all three bones. The combined running protocol had positive effects on the trabecular thickness in the distal ulna. The HIIT protocol resulted in an increase in both medio-lateral diameter and cortical bone area over total area (Ct.Ar/Tt.Ar) at the ulnar shaft compared with sedentary condition. Moreover, the HIIT protocol decreased the mean surface area of the medulla (Ma.Ar) according to sedentary condition at the ulnar shaft. This study has shown that HIIT resulted in a decrease in trabecular bone fraction in favor of cortical bone area at the ulna.

Molecular cloning and characterization of a brassinosteriod biosynthesis-related gene PtoCYP90D1 from Populus tomentosa

Brassinosteroids (BRs), one of the major classes of phytohormones are essential for various processes of plant growth, development, and adaptations to biotic and abiotic stresses. In Arabidopsis, AtCYP90D1 acts as a bifunctional cytochrome P450 monooxygenase, catalyzing C-23 hydroxylation in the brassinolide biosynthetic pathway. The present study reports the functional characterizations of PtoCYP90D1, one of the AtCYP90D1 homologous genes from Populus tomentosa. The qRT-PCR analysis showed that PtoCYP90D1 was highly expressed in roots and old leaves. Overexpression of PtoCYP90D1 (PtoCYP90D1-OE) in poplar promoted growth and biomass yield, as well as increased xylem area and cell layers. Transgenic plants exhibited a significant increase in plant height and stem diameter as compared to the wild type. In contrast, the CRISPR/Cas9-generated mutation of PtoCYP90D1 (PtoCYP90D1-KO) resulted in significantly decreased biomass production in transgenic plants. Further studies revealed that cell wall components increased significantly in PtoCYP90D1-OE lines but not in PtoCYP90D1-KO lines, as compared to wild-type plants. Overall, the findings indicate a positive role of PtoCYP90D1 in improving growth rate and elevating biomass production in poplar, which will have positive implications for its versatile industrial or agricultural applications.

Numerical Simulation on the Influence of the Distribution Characteristics of Cracks and Solution Cavities on the Wellbore Stability in Carbonate Formation

The development of cracks and solution cavities in carbonate reservoirs can notably reduce the rock’s mechanical properties, leading to a severe wellbore collapse problem during drilling operations. To clarify the influence of the characteristics of cracks and solution cavities on the wellbore stability in the Dengying Formation carbonate reservoir in the Gaoshiti–Moxi area of Sichuan, the mechanical properties of carbonate rock were analyzed. Then, the influences of the attitude and width of cracks, the size and quantity of solution cavities, and their connectivity on wellbore stability were studied using FLAC3D 6.00 numerical simulation software. Our results show the following: (1) The cracks and solution cavities in the Dengying Formation carbonate rock cause significant differences in the rock’s mechanical properties. (2) The equivalent drilling fluid density of collapse pressure (ρc) considering the effects of cracks and solution cavities is 6.4% higher than without these effects, which is in good accordance with engineering practice. Additionally, cracks play a more significant role than solution cavities in affecting the wellbore stability. (3) When the orientation of a crack is closer to the direction of maximum horizontal stress, and the dip angle and width of the crack increase, the stress and deformation at the intersection of the crack and wellbore gradually increase, and correspondingly, ρc also increases. (4) The stress and displacement of various points around the solution cavities gradually increase with the increases in diameter and quantity of solution cavities, and ρc also increases. (5) Compared with the situation where cracks and solution cavities are not interconnected, the stress disturbance area around the wellbore is larger, and ρc is greater when cracks and solution cavities are interconnected.

Study on characterization of flame propagation of spontaneous ignition caused by high-pressure hydrogen leakage

As an ideal energy source, hydrogen is highly susceptible to spontaneous ignition once leaked, which is an urgent issue that needs to be addressed. Based on the shock tube model, this paper investigates flame propagation under various pressures, tube lengths, and diameters by employing the LES approach and a detailed hydrogen/air combustion mechanism. The results indicate that within the tube, the ignition kernels gradually evolve into tulip flames when specific conditions are satisfied. As pressure and tube length increase, the likelihood of forming a complete flame rises significantly; with the increase of tube diameter, the flame front is flatter and the flame intensity is more uniformly distributed. Furthermore, this paper develops a model to predict the formation of a complete flame: Pb/Pa=570.64(L/D)−0.6. Outside the tube, once the intact flame passes out of the tube and evolves into a jet flame, structures such as flame envelopes and jet vortices will appear. Higher release pressures make it more difficult for the flame to propagate steadily, whereas increasing tube length and diameter promotes combustion and sustains the flame outside the tube.

Effects of Tube Diameter and Gas Flow Rate on the Discharge Dynamics Characteristics and Reactive Species of Nanosecond Pulsed Discharge Plasma in Contact With Water

ABSTRACTThe use of millimeter quartz tubes to generate non‐thermal plasma in contact with liquid is widely applied in medicine, such as the effective disinfection of catheter tubes and tooth cavities. Here, the effects of tube diameter and gas flow rate on discharge dynamics and reactive species characteristics of nanosecond pulse needle‐water discharge are studied using an ICCD camera and optical emission spectra. The discharge diffusion is increased significantly by an appropriate combination of tube diameter and gas flow rate. Besides, the discharge intensity, emission spectra intensities of reactive species, gas temperature, and electron density increase with the increase of quartz tube diameter and gas flow rate, which contributes to enhance the production of OH and H2O2 species in aqueous samples.

Multi-scale reservoir response characteristics of coalbed methane development through stress relief via horizontal well cavity completion in tectonically deformed coals

China’s coalbed methane (CBM) resources hold significant potential. However, the widespread presence of soft and low-permeability tectonically deformed coal (TDC) presents a challenge to the efficient development of CBM. The development of CBM through stress relief via horizontal well cavity completion (HWCC) offers a promising innovative solution to this problem. To elucidate the multi-scale reservoir response characteristics of CBM development through stress relief via HWCC in TDCs, this article comprehensively employs particle discrete element and finite element numerical simulation methods, and carries out the numerical simulation studies of cyclic seepage at the specimen scale, HWCC at the coal seam scale, and CBM development at the coal seam group scale. The main findings are summarized as follows. Unlike the stress-compression specimens, which exhibited overall failure, the differential distribution of pressure gradients within the specimens during the gas seepage experiments resulted in the development of microcracks concentrated at the bottom of the specimens. With the escalation of coal body structural damage, the permeability stress compression coefficient during the elastic deformation stage shows an increasing trend. Upon entering the plastic deformation stage, the specimen’s permeability shifts from a decreasing to an increasing trend. Increasing the lower limit pressure ratio, upper limit pressure ratio, and cycle rate of gas injection pressure could accelerate the failure efficiency of the specimens. Increasing the lower limit pressure ratio has a more pronounced effect on the TDC specimens, while increasing the upper limit pressure ratio has a more significant impact on the primary undeformed and cataclastic coal specimens. In TDCs, the phenomenon of wellbore collapse and cavity expansion becomes more pronounced. The cavity volume tends to increase with the increase in the initial well diameter, in-situ stress, and alternating bottom-hole pressure differences. The HWCC could enhances reservoir permeability and production in both the cavity completed and adjacent coal seams. For two horizontal wells with cavity completions in the same layer, excessively close well spacing is unfavorable for fostering inter-well interference and reservoir pressure drop. When the HWCC is applied to thin coal seams, the enhancement of permeability and production is limited. Reasonable optimization of drainage rates could effectively mitigate the reservoir permeability velocity-sensitive damage. The research findings extend related theories and provide a robust reference for subsequent practical engineering applications.

Optimizing Cookie Formulation Using a Composite Flour Blend of Soybean, Beetroot, and Wheat: Effects on Physicochemical and Phytonutrient Characteristics

This study aimed to optimize cookie formulation using a composite flour blend of soybean (SF), beetroot (BF), and wheat (WF). Four blends were formulated: 50% WF:45% SF:5% BF (T1), 50% WF:35% SF:15% BF (T2), 50% WF:25% SF:25% BF (T3), and 100% WF (Control) (T4) for cookie preparation. The inclusion of SF and BF had significant effects on the physical, chemical, and phytonutrient attributes of the cookies. Results showed an increase in diameter and height with the addition of beetroot and soy flour. T2 had the highest weight (9.57g), diameter (5.42cm), and spread ratio (6.46) among the blends, while T3 had the highest total color difference. T1 cookies had higher levels of protein, crude fiber, total phenolic content, and total antioxidant activity compared to the control. Statistical analysis indicated that the sensory characteristics of the cookies were not significantly affected by the addition of soy and beetroot flours. This study suggests that composite flour cookies enriched with nutritional and antioxidant properties can be developed by incorporating varying levels of beetroot and soy flour alongside wheat flour.