Increase In Dosage Research Articles

A feasibility study on using tire-recycled steel fibers to enhance the toughness of constructional backfill body

Constructional backfill body (CBB) commonly faces the issue of high brittleness and low toughness. Herein, a novel approach is proposed to improve the toughness of CBB using tire-recycled steel fibers (RSF). Thus, the impact of different RSF dosages on the performance of CBB was investigated. The results showed that compared to the mixtures without RSF, the slump values of the fresh mixtures decreased by 5.49%, 12.94%, and 23.14%, respectively, when the RSF dosages were 0.5%, 1%, and 1.5%. However, the slump values of all test groups remained above 190mm, meeting the requirements for workability. The incorporation of RSF led to a decrease in uniaxial compressive strength, with the degree of decrease following the order of 1.5%, 0.5%, and 1% dosages. However, all test groups met the requirements for the strength of CBB. Toughness increased with the increase in the RSF dosage, but the toughening effect diminished with the increase in the curing age. Hydration products encapsulated RSF, and RSF of different diameters and lengths jointly inhibited the expansion of CBB cracks, which is the fundamental reason for the improvement in toughness. The geometric variability of RSF enhanced mechanical interlocking, bridging, and inlaying effects, further contributing to the toughness of CBB. Industrial test results demonstrated that throughout the entire mining process, CBB did not experience fracturing or instability, proving the feasibility of using RSF to toughen CBB. The research findings are conducive to improving underground space safety and exploring large-scale reuse pathways for waste tires.

Degradation of salicylic acid coordinated to Fe3O4 nanoparticles by H2O2

Salicylic acid (SA) has strong tendency to form complexes with iron (III). Depending upon the concentrations of SA, the complexes formed are FeR+, FeR2+, FeR32+where R represents salicylate ion (-OC₆H₄COO-). Fe3O4 nanoparticles binds with the salicylate ions through the sites having Fe3+ and at the site containing Fe2+ reacts with H2O2 to produces OH* radicals. The OH* radicals oxidise the salicylic acid attached to Fe3O4 nanoparticles. Thus, the degradation occurs through the formation of SA-Fe3O4 nanoparticles complexes and then followed by the reaction with H2O2 at the nanoparticle site. FT-IR, TGA were used to confirm the synthesis of Fe3O4 nanoparticles as well as to investigate SA-Fe3O4 nanoparticles complex formation and the degradation of the complex by H2O2. Spectrophotometric studies were employed for the monitoring of the degradation of SA at the surface. Here, the nanoparticles act as platform to which both the reactants SA and H2O2 get activated and the degradation reaction occurs. The concentrations of SA, H2O2, nanoparticle dosage, surfactants and polymers were changed and the % degradation were noted. It has been observed that the degradation percentage decreased with the increase in nanoparticle dosage, [surfactant] and [polymers]. The [H2O2] and [HClO4] gave peaked-like curve for the degradation of SA for the plot of % degradation versus concentrations of H2O2 and HClO4. Degradation of SA was observed maximum at [H2O2](= 8.0 × 10−4 mol dm−3) and at [HClO4] (= 1.0 × 10−2 mol dm−3).

Influence of FA and HPMC on the fresh properties and anisotropy of 3D printing engineered cementitious composites (3DP-ECC)

To investigate the effect of material compositions on the fresh properties and anisotropy of 3DP-ECC, the shape retention and the anisotropy of the compressive strength of 3DP-ECC with different contents of fly ash (FA) and Hydroxypropyl methyl cellulose (HPMC) were studied. The research results indicated that FA could weaken the shape retention, but HPMC significantly enhanced the shape retention of the fresh slurry of 3DP-ECC. The compressive strength in different directions was ranked as Z > Y > X. With the increase of dosage (FA/HPMC), the isotropy in the compressive strength of 3DP-ECC with HPMC decreased, but the difference of 3DP-ECC with FA became more obvious gradually.

A Case Report of Verapamil Toxicity Leading to Hemodynamic Compromise in Obstructive Hypertrophic Cardiomyopathy

Abstract Background Hypertrophic cardiomyopathy (HCM) is an inherited condition characterized by left ventricular hypertrophy unexplained by increased afterload, often with concomitant outflow tract obstruction. Verapamil is commonly used to treat symptomatic patients. However, its potential for adverse effects should be recognized. Case Summary This report provides a case of cardiogenic shock in HCM, where a patient presented with chief complaint of fatigue and shortness of breath with an acute decline in left ventricular systolic function on echocardiogram. His symptoms were attributed to verapamil toxicity following a recent increase in dosage. He achieved rapid symptom relief after holding his home medications, in addition to conservative management. Conclusion This case report aims to elucidate the potential for multiple adverse effects involved with verapamil use in patients with obstructive hypertrophic cardiomyopathy

The Efficacy of Combined “Oral Simvastatin Plus Narrowband UVB Phototherapy” Than “Phototherapy Alone” in Treating Skin Lesions in Patients with Vitiligo, a Double-Blind Add-On Randomized Controlled Clinical Trial

Background: A tailored therapy for vitiligo is crucial in enhancing patients' quality of life and decreasing the associated dimensions. In addition, statins play a significant function in modulating the immune system. Objectives: This study investigated the efficacy of oral simvastatin in treating skin lesions in patients with vitiligo. Methods: This interventional randomized clinical trial enrolled 50 vitiligo patients referred to Shahid Faghihi Hospital in Shiraz (Iran) in 2015. Participants were divided into control and intervention groups using block randomization. Participants in the control group received “NB-UVB phototherapy plus placebo,” and those in the intervention group received “NB-UVB phototherapy with 40, 60, and 80 mg simvastatin by a monthly increase in the drug dosage”. A reduction in the Vitiligo Area Scoring Index (VASI) score and side effects were measured for four months, and the results were compared between the two groups. Results: At the start of the study, the mean score for the disease severity was equal for both groups (P ˃ 0.05). However, the disease severity was significantly reduced in the following stages of the study in the simvastatin group compared to the placebo group (P = 0.0001). Conclusions: Oral simvastatin enhances the photothermal outcomes while exerting trivial side effects. Thus, combining oral simvastatin with phototherapy is recommended as a potent strategy for treating patients with vitiligo.

Ciprofloxacin Dosage Optimization in Cystic Fibrosis Through Therapeutic Drug Monitoring

Background: Ciprofloxacin (CIP) is effective against many Gram-negative pathogens and penetrates well into respiratory secretions and pulmonary tissues, thus making it useful for treating respiratory infections in patients with cystic fibrosis (CF). Methods: A 13-year-old patient with severe CF and an acute respiratory exacerbation from multidrug-resistant Pseudomonas aeruginosa was treated with 700 mg of CIP every 8 hours. Bronchial secretions confirmed that P. aeruginosa was sensitive to high doses of CIP. Pharmacokinetic monitoring using 2 blood samples estimated the AUC24 at 50 hours*mg/L. This led to an increase in CIP dosage to 850 mg three time a day (TID), then to 1000 mg TID, and finally to 1200 mg every 6 hours. Results: CIP pharmacokinetics can vary significantly, particularly in patients with CF due to increased clearance, ultimately resulting in shorter half-lives and higher risks of therapeutic failure and resistance. Therapeutic drug monitoring helps when adjusting dosages to maintain effective blood concentrations. Conclusions: This case underscores the role of therapeutic drug monitoring in optimizing CIP dosing for patients with CF and highlights the necessity for close collaboration between clinicians and pharmacologists to ensure effective antibiotic exposure.

Impacts of Nano-Composite of Copper and Carbon on Intestinal Luminal Micro-Ecosystem and Mucosal Homeostasis of Yellow-Feather Broilers.

The present study was undertaken to evaluate the impacts of nano-composites of copper and carbon (NCCC) on the intestinal luminal micro-ecosystem and mucosal homeostasis of yellow-feather broilers. A total of two-hundred and forty 1-day-old male yellow-feather broilers were randomly allocated into four groups, each with five replications of twelve birds. The control (CON) group received a corn-soybean basal diet, while the N50, N100, and N200 groups were supplemented with 50, 100, and 200 mg/kg of NCCC in basal diets, respectively. The trial duration was 63 days. The findings demonstrated that there were slight impacts of NCCC addition on the intestinal luminal micro-ecosystem of broilers, with the fecal moisture content in the N100 group being slightly higher on Day 3 in the starter phase (p < 0.05). The cecal microbiota structure also did not obviously change (p > 0.05), in spite of the fall in the relative abundance of the Ruminococcus torques group in the N50 group and norank Clostridia UCG-014 in N200 group (p < 0.05). But for intestinal mucosal homeostasis, NCCC played a crucial part in jejunal morphology, tight junction, immunologic status, and antioxidant capacity. There was linear growth in villus height and a quadratic increase in villus height, crypt depth and their ratio with the increase in NCCC dosage (p < 0.05), and 100 mg/kg NCCC supplementation could intensify the expression of CLDN-3 genes (p < 0.05). In addition, IL-4 and IL-10 linearly increased after NCCC treatment (p < 0.05), along with some irregular changes in sIgA (p < 0.05). In addition, higher jejunal mucosal total antioxidant capacities in N50 and N200 groups were also observed (p < 0.05). Overall, NCCC treatment optimized the intestinal mucosa function of broilers in terms of physical barrier and immune and antioxidant capacities, but exerted subtle influence in the luminal environment of yellow-feather broilers. More precisely, dietary supplementation with 50 mg/kg NCCC is recommended for intestinal homeostasis of broilers.

Iron coagulant regulating reactive species in ionizing radiation process for enhanced degradation of bisphenol A

In the treatment of industrial wastewater by electron beam technology, the flocculation process was frequently coupled with electron beam radiation to improve the water quality to meet the discharge standard. Iron-containing coagulant was widely used in the flocculation process. Therefore, this study investigated the impact of residual iron-containing coagulants on pollutant degradation by the ionizing radiation process. Results showed that the absorbed dose required for complete removal of 50 mg/L bisphenol A decreased from 5 kGy to 2.5 kGy in the presence of 100 μM typical iron coagulant (FeCl3). BPA degradation efficiency increased with the increase of FeCl3 dosage over a wide pH range (3.0–10.0), and the TOC removal efficiency increased from 20% to 45% with the addition of 300 μM Fe(III). The mechanistic investigation demonstrated that •OH was the primary reactive species responsible for BPA degradation. The residual iron coagulants (FeCl3) significantly enhanced the degradation and mineralization efficiency. Under suitable pH conditions (3.0–6.0), the reducing reactive species (eaq‒ and •H) could effectively reduce Fe(III) to Fe(II), which then reacted with H2O2, thus inducing in-situ Fenton reaction to generate more •OH, thus promoting the radiolysis degradation of micropollutants. This study explored the potential of using residual iron coagulants from the flocculation process to enhance the performance of electron beam technology for wastewater treatment.

Relapse risk factors and clinical characteristics of idiopathic inflammatory myopathies in 105 patients.

To identify the risk factors for relapse of idiopathic inflammatory myopathies (IIMs). Patients who were newly diagnosed with IIMs and underwent muscle biopsy between 2000 and 2017 at Asan Medical Center were retrospectively reviewed. The relapse of IIMs was defined as the recurrence of muscle or cutaneous manifestations with a ≥50% increase in glucocorticoid dosage after reaching the low-dose glucocorticoid phase with clinically significant improvement. The factors associated with the relapse of IIMs were investigated by Cox proportional hazards analysis. Of 105 patients with IIMs, relapse was observed in 65 patients (62%). The titer of antinuclear antibody (ANA) was higher in the relapse group than in the non-relapse group (P = 0.033). Multivariable analysis showed that the relapse of IIMs was significantly associated with histopathologic features consistent with IIMs (hazard ratio [HR], 1.69; 95% confidence interval [CI], 1.01-2.83, P = 0.045) and the use of immunosuppressants before relapse (HR, 0.50; 95% CI, 0.29-0.86, P = 0.013). Doubling of ANA titer was also associated with relapse, albeit without statistical significance (HR, 1.13; 95% CI, 1.00-1.27, P = 0.052). In patients with IIMs, the use of immunosuppressants had a significant negative association with relapse. Administering immunosuppressants from the early period during the initial glucocorticoid tapering phase may be useful in reducing the risk of relapse in patients with IIMs. Key Points • Since idiopathic inflammatory myopathies (IIMs) have a low prevalence, it is poorly understood which factors are associated with the relapse of IIMs. • In this study, about two-thirds of 105 patients with IIMs experienced a relapse of IIMs. • The risk of relapse in patients with IIMs was negatively associated with the use of immunosuppressants during glucocorticoid tapering and low-dose glucocorticoid phase. • Even in less severe cases, the use of immunosuppressants might be a good option for the management of IIMs.

Modulation of shape memory properties of trans-polyisoprene by sulfur

Abstract In this paper, TPI/S composites were prepared by a simple physical melt blending method, and the composites were hot-pressed and molded using a vulcanization system. The effect of cross-linking on the vulcanization properties, mechanical properties, crystalline properties, and shape memory properties of trans-1-4 polyisoprene (TPI) was investigated by varying the amount of sulfur (S). It was shown that with the increase of sulfur dosage, both TPI scorch time and orthoclave time were shortened and the mechanical properties decreased; The melting peak area and melting temperature of the crystalline region of TPI decreased with the increase of sulfur content, and the cross-linking density increased while the crystallinity tended to decrease and the heat resistance deteriorated; In addition, with the increase of sulfur content, the shape return rate of TPI/S composites was increasing and the shape fixation rate was decreasing. When the TPI/S composites were used as shape memory materials, the sulfur dosage of 1 phr had the best shape memory performance, at which time the shape fixation rate of the composites reached 96.9% and the shape recovery rate reached 86.2%. When the sulfur content was elevated to 2 phr, the shape memory fixation rate was significantly decreased, indicating that the shape memory properties were severely compromised. This study reveals that the quantity of sulfur exerts a significant influence on the application of TPI/S composites. An appropriate amount of sulfur can facilitate the preparation of thermoplastic elastomers for utilization in shape memory materials. Nevertheless, an excessive amount of sulfur will substantially enhance the internal cross-linked structure of the composite and deteriorate the shape memory performance.

Evaluating corticosteroid treatment strategies for cardiac sarcoidosis: analysis of the nationwide claims-based JROAD-DPC dataset

Abstract Background Corticosteroid-based immunosuppressive therapy is the cornerstone of treatment for cardiac sarcoidosis (CS), aimed at preventing severe adverse events including death, heart failure and lethal arrhythmic events. Nevertheless, data on the optimal initial dosing, appropriate tapering schedules, suitable maintenance dosages, and the recurrence rates among patients are insufficient. Purpose This study sought to scrutinize real-world data on corticosteroid therapy regimen for CS and to reassess optimal treatment protocols. Methods From the Japanese Diagnosis Procedure Combination database, 6,282 patients with hospitalized CS were identified between 2012 and 2022. Among them, 3,067 CS patients who were initiated on corticosteroid therapy during hospitalization were analyzed. We examined the baseline patient characteristics and treatment strategies for corticosteroid therapy, including starting dose, tapering period, maintenance dose, and their correlation with the onset of adverse events. Results The cohort had a mean age was 63±11 years, and 1,256 patients (41.0 %) were female. The starting dose of corticosteroids was 30.3±6.9 mg, with 88.6% of patients receiving a dose of ≧30 mg/day. The doses of corticosteroids at 30, 60, 90, 120, 150 and 180 days post-discharge were 21.4±9.8, 15.7±6.9, 12.2±5.7, 10.4±5.0, 9.3±4.5 and 9.0±4.6 mg, respectively. By day 180, 83.7% of the patients were maintained on ≦10 mg/day. However, 17.1 % of patients required an increase in corticosteroid dosage during the tapering course, primarily due to exacerbation of sarcoidosis. When analyzing only the group without corticosteroid escalation up to 180 days post-discharge, the average corticosteroid dose was 8.7±3.8 mg, with 95.3% of patients on ≦10 mg/day. We observed 965 re-hospitalization (31.5 %) during follow-up, with 58.8% of these patients having corticosteroid escalation to ≧30 mg, and 12.8% of patients received second-line immunosuppressive therapy, such as methotrexate. Conclusion The majority of CS patients were initiated on a corticosteroid regimen of 30 mg/day, which was subsequently tapered to below 10 mg/day by day 180. However, non-negligible number of patients experienced clinical events or relapse, underscoring the necessity for vigilant follow-up during corticosteroid therapy.Figure

Evaluation effect of alginate hydrogel containing losartan on wound healing and gene expression.

Skin tissue engineering has become an increasingly popular alternative to conventional treatments for skin injuries. Hydrogels, owing to their advantages have become the ideal option for wound dressing, and they are extensively employed in a mixture of different drugs to accelerate wound healing. Sodium alginate is a readily available natural polymer with advantages such as bio-compatibility and a non-toxicological nature that is commonly used in hydrogel form for medical applications such as wound repair and drug delivery in skin regenerative medicine. Losartan is a medicine called angiotensin receptor blocker (ARB) that can prevent fibrosis by inhibiting AT1R (angiotensin II type 1 receptor). In this research, for the first time, three-dimensional scaffolds based on cross-linked alginate hydrogel with CaCl2 containing different concentrations of losartan for slow drug release and exudate absorption were prepared and characterized as wound dressing. Alginate hydrogel was mixed with 10, 1, 0.1, and 0.01mg/mL of losartan, and their properties such as morphology, chemical structure, water uptake properties, biodegradability, stability assay, rheology, blood compatibility, and cellular response were evaluated. In addition, the therapeutic efficiency of the developed hydrogels was then assessed in an in vitro wound healing model and with a gene expression. The results revealed that the hydrogel produced was very porous (porosity of 47.37 ± 3.76µm) with interconnected pores and biodegradable (weight loss percentage of 60.93 ± 4.51% over 14days). All hydrogel formulations have stability under various conditions. The use of CaCl2 as a cross-linker led to an increase in the viscosity of alginate hydrogels. An in vitro cell growth study revealed that no cytotoxicity was observed at the suggested dosage of the hydrogel. Increases in Losartan dosage, however, caused hemolysis. In vivo study in adult male rats with a full-thickness model showed greater than 80% improvement of the primary wound region after 2weeks of treatment with alginate hydrogel containing 0.1mg/mL Losartan. RT-PCR and immunohistochemistry analysis showed a decrease in expression level of TGF-β1 and VEGF in treatment groups. Histological analysis demonstrated that the alginate hydrogel containing Losartan can be effective in wound repair by decreasing the size of the scar and tissue remodeling, as evidenced by future in vivo studies.

Evaluation and comparison for higher temperature performance index of emulsified asphalt mastic using coal gangue powder

In order to investigate the rheological behavior and the influence of solid waste coal gangue powder on the high-temperature performance of cold recycled Emulsified Asphalt Mastics (EAM), Dynamic Shear Rheometer (DSR) and Multiple Stress Creep Recovery (MSCR) tests were conducted using three different fillers and four powder-to-binder ratios of EAM. Evaluation indexes such as rutting factor (G*/sinδ), improved rutting factor (G*/1−1/sinδ∙tanδ), Unrecoverable Creep Compliance (Jnr), Cumulative Strain (CS) and Creep Recovery Ratio (R) were used to analyze the influence of filler type and dosage on high temperature of EAM, and the effectiveness of these indexes to evaluate high temperature is considered. Moreover, atomic force microscopy experiments were carried out to study on interaction mechanism between the fillers and emulsified asphalt. Finally, grey relational analysis method was used for quantitative assessment of these indexes for EAM. The results indicate that all three fillers effectively improve the high-temperature performance, with a larger improvement observed as the filler dosage increases, among which the tunneling coal gangue powder is the most significant. Under a stress level of 0.1 KPa, the coal gangue filler mastic appears the best deformation recovery ability, whereas under a stress level of 3.2 KPa, the cement filler mastics appears the best deformation recovery ability. The additional fillers significantly influence the nano-scale surface morphology of the residues, and the tunneling coal gangue powder appears a stronger adsorption capacity for free polar components compared to the cement and limestone mineral powder. It is suggested that the Jnr and CS can be used as evaluation indexes of high temperature evaluation index of EAM, instead of G*/1−1/sinδ∙tanδ or G*/sinδ or R.

Study on the properties of alkali-activated ferrochrome slag paste filling materials prepared from multiple industrial solid wastes

ABSTRACT The enormous utilization potential of industrial solid waste in cemented paste backfill (CPB) materials has attracted considerable interest. To solve the treatment challenges of ferrochrome slag (FS), a green ferrochrome slag cemented paste backfill materials (FS-CPB) composed of FS, desulfurization gypsum (DG) and granulated blast furnace slag (GBFS) was proposed in the study. The setting time, slump, uniaxial compressive strength (UCS), microstructure and leaching behavior of FS-CPB were systematically investigated. The results indicated that FS and DG showed retarding properties, while the setting time first decreased and then increased with the increase of polycarboxylate superplasticizers (PCE) and sodium silicate dosage. The slump was positively correlated with FS and sodium silicate dosage. However, the addition of DG and PCE can improve the fluidity properties. The optimum UCS values (3 d: 0.92 MPa; 7 d: 2.43 MPa; 14 d: 3.19 MPa; 28 d: 4.58 MPa) was obtained with 6% sodium silicate. Moreover, the primary hydration products of FS-CPB were ettringite, C-S-H gels and N-A-S-H gels. The leaching concentrations of total Cr and Cr(VI) satisfied the Class Ι water quality standard limits (≤1.5 mg∙L−1) in GB 8978–1996 and Class III water quality standard limits (≤0.05 mg∙L−1) in GB 14,848-2017, respectively. The research results in this paper can provide new options for cement substitutes in mining companies and guide the large-scale application of FS.

Neurological care and outcomes in a cohort of Canadian pregnant patients with epilepsy

PurposeTo characterize anti-seizure medication (ASM) use over time, therapeutic drug monitoring, ASM dose adjustments and gestational seizure frequency among Canadian people with epilepsy of childbearing potential seen in an urban tertiary care center. MethodsParticipants were retrospectively identified from the medical records of pregnant patients with epilepsy seen at the University Health Network Comprehensive Epilepsy Program between 2014 and 2021. A descriptive analysis of outcomes, a logistic regression analysis of the odds of patients being on three ASMs associated with higher rates of teratogenicity (i.e., valproate, carbamazepine, and topiramate) over time, and a second logistic regression for predictors of seizure freedom during pregnancy were performed. Results195 pregnancies were included: 52 % had a maternal diagnosis of generalized epilepsy and 92 % were prescribed at least one ASM, with 75 % on monotherapy. The majority underwent therapeutic drug monitoring (77 %) with approximately two-thirds requiring dose adjustments (69 %), typically dosage increases (82 %). The proportion of patients on either valproate, topiramate, or carbamazepine decreased over time (OR=0.80; p<0.01). Fifty-seven percent of pregnancies maintained seizure freedom, with seizure-freedom for ≥1 year prior to conception being the strongest predictor of this outcome (OR of gestational seizure recurrence=0.04; p < 0.01). ConclusionThe proportion of patients on three ASMs associated with higher rates of teratogenicity has decreased over the duration of this study. Seizure-freedom prior to conception was associated with a decreased risk of gestational seizure recurrence.

Study on the Chloride–Sulfate Resistance of a Metakaolin-Based Geopolymer Mortar

The chloride–sulfate corrosion environment of concrete is a significant engineering problem. This paper investigates the effect of the complete/semi–immersion mode on the durability of concrete in a chloride–sulfate environment by using different granulated blast furnace slag (GBFS) dosage rates (10–50%) of a metakaolin (MK)-based geopolymer mortar. The chloride–sulfate corrosion environment is discussed by analyzing the apparent morphology, mass change, and mechanical property change in specimens at the age of 120 d of erosion combined with XRD and SEM. The high Ca content in GBFS has an important effect on the strength and erosion resistance of the metakaolin geopolymer (MGP) group mortar; an increase in the GBFS dosage makes the MGP group mortar denser, and the initial strength of the MGP group mortar is positively correlated with the dosage of GBFS. After 120 d of erosion, the GBFS dosage is negatively correlated with erosion resistance, with the high GBFS dosage groups showing more severe damage. Semi-immersion resulted in more severe deterioration at the immersion–evaporation interface zone due to the difference in the ionic concentration and the ‘wick effect’ at the immersion–evaporation interface zone. Compared with the commonly used OPC mortar, the M40 and M50 groups have improved strength and corrosion resistance and are suitable for engineering environments in highly erosive areas.

Comparative Remediation of Arsenic and Antimony Co-Contaminated Soil by Iron- and Manganese-Modified Activated Carbon and Biochar.

At present, soil contaminated with arsenic (As) and antimony (Sb) is escalating at an alarming rate, which is harmful to human health. In this study, Fe- and Mn-modified activated carbon (AC) and biochar (BC) were prepared and compared for the remediation of As- and Sb-contaminated soil. The effects on the speciation of As and Sb, soil pH, organic matter (SOM), and enzyme activity with various dosages and remediation times were investigated. The results showed that on the whole, the best stabilization effect of As and Sb was achieved with 3% FeMnBC. Furthermore, with increases in time and dosage, the immobilization effect on As and Sb was more significant. Fe/Mn-modified AC and BC enhanced soil pH, with 3% MnAC being particularly effective; 3% AC and 3% FeMnAC demonstrated the most pronounced enhancement in SOM. The modified carbon materials exhibited a dramatic increase in enzymatic activity. In particular, urease activity showed an increasing trend, and catalase activity first decreased and then increased over 30 days. Among the treatments, 3% MnAC showed the most significant enhancements in catalase and urease activities, whereas 1% FeMnBC had the most pronounced effect on increasing sucrase activity. This study provides theoretical support for the remediation of soil co-contaminated with As and Sb by Fe/Mn-modified AC and BC.

Research on the micro-mechanism and factors of hot recycled asphalt binder cracking

The poor low-temperature performance of recycled asphalt is the primary cause of the recycled asphalt disease. However, further strengthening is required to analyze the molecular-level cracking of recycled asphalt. This article presented a comprehensive investigation of the cracking phenomenon of recycled asphalt at both the macro and micro levels. This was achieved through the utilization of experimental tests and molecular dynamics simulations. In this study, pressure-aged asphalt was subjected to 40 h of aging. The aged asphalt was divided into three groups: 30% RAP (reclaimed asphalt pavement) recycled asphalt, 50% RAP recycled asphalt, and 70% RAP recycled asphalt. The three groups were then analyzed in terms of three major indexes. Linear amplitude scanning (linear amplitude sweep, LAS) was conducted on the three groups. The mechanical response law of asphalt was obtained, and it was found that the coefficient of strength of recycled asphalt increased with the increase of RAP dosage. At the same time, the fracture energy density decreased subsequently. Furthermore, the fracture energy density of aged asphalt was 7% lower than base asphalt's. Subsequently, this study examined the four fractions and C=O and S=O functional groups of five types of asphalt and constructed the molecular structures and models of stable base asphalt and aged asphalt. Subsequently, this article constructed a fusion model of new and old asphalt, analyzed the fusion process of new and old asphalt, and studied the factors affecting the blending degree of new and old asphalt. Finally, the factors affecting the cracking performance of rejuvenated asphalt, including the blending degree, the content of the four fractions, and the addition of the rejuvenator, were investigated. The impact of each influencing factor on the cracking performance of recycled asphalt was analyzed from multiple perspectives. In conclusion, the findings of this study provide a valuable guide for interpreting the tensile properties of reclaimed asphalt and the influence of rejuvenators.

Synthesis and characterization of Selenicereus undatus extract mediated nano-Bi2O3 and its application in the adsorption of Rhodamine B dye

Betacyanins (BC) are reddish-purple pigments widely found in the peels of white-fleshed dragon fruit (Selenicereus undatus) and peels and pulps of red-fleshed dragon fruit (Selenicereus costaricensis). BC pigments are good anti-oxidants that inhibit the formation of reactive oxygen species (ROS) in plants and thereby promote the reduction of metal ions to zero-valent metals. It also acts as a good stabilizing and capping agent in the synthesis of nanoparticles. Hence, this research aims to extract, and quantize the content of BC from the peels of Selenicereus undatus, to fabricate betacyanin-rich- Selenicereus undatus (SU) modified bismuth oxide nanoparticles (Bi2O3 NPs) and characterize using UV-Vis, FTIR, XRD, SEM, EDAX, and BET. The quantity and stability of the betacyanin are optimized using various parameters like time, temperature, solvent ratio, pH, etc., through a UV-Vis spectrophotometer at 538 nm. Synthesized SU-Bi2O3 NPs aim to alleviate synthetic dye contaminants through adsorption- an efficient route for water remediation. The nano-adsorbent Bi2O3 NPs showed an increase in dye adsorption with an increase in reaction time, temperature, and Bi2O3 NPs dosage, enabling efficient removal of dyes such as Rhodamine B (RhB) dyes.

A novel measurement method of thermal performances for an improved thermal storage concrete with microencapsulated phase change materials

Integrating micro-encapsulated phase change materials into concrete member is among the effective strategies to optimize its thermal properties. However, the addition of microencapsulated phase change materials changes the meso-structure and heat storage of concrete, which gives rise to the difference in measurement method of thermal properties between common concrete and concrete with micro-encapsulated phase change materials. The primary aim of this paper is to develop an experimental model that takes into consideration both the structure and phase-transition characteristics of concrete with micro-encapsulated phase change material. The developed experimental model consists of three Modules that form different thermal boundary conditions to test specific heat capacity, latent heat, thermal conductivity, and heat attenuation. To investigate the effect of environment temperature on the thermal properties, three groups of concrete slabs with different micro-encapsulated phase change material dosage were fabricated and tested. Results shown that the environment temperature has little effect on both specific heat capacity and thermal conductivity of concrete without micro-encapsulated phase change material, while significantly affects that of concrete containing micro-encapsulated phase change material. The specific heat capacity of concrete with 5.0 % micro-encapsulated phase change material was 1.273 J/g °C at around 28 °C, yet 0.958 J/g °C at around 18 °C.The thermal conductivity of concrete with micro-encapsulated phase change material was affected by both paraffin state and dosage. The thermal conductivity of the concrete with 5.0 % micro-encapsulated phase change material reduced by 8.44 % when the state of paraffin changed from solid to liquid. The latent heat of concrete with micro-encapsulated phase change material were enhanced. Additionally, the heat attenuation ascends by 32.34 % when the MPCM dosage increase from 0.0 % to 5.0 %.