Increase In Dosage Research Articles

Synthesis of Activated Charcoal from Coconut Shell for the Removal of Crude Oil Spill

Crude oil spills have devastating effects on the environment, particularly aquatic ecosystems. The purpose of the present research is to determine whether dry coconut shells can be used as raw materials to make activated charcoal (AC) via pyrolysis and whether they can be utilized as natural sorbents to clean up crude oil spills. The UV-Vis spectrum of the synthesized CSAC shows distinct peaks at 230 and 260 nm, whereas the activated charcoal exhibits peaks at 231 and 261 nm. The FTIR spectra of the synthesized CSAC reveal a medium broad absorption peak at 3307.2 cm⁻¹, while the raw coconut shell's FTIR spectra show a medium sharp peak at 2945.3 cm⁻¹. The SEM images highlight the unique structural properties of CSAC, showcasing high porosity, varied pore sizes, rough surface topography, and the presence of micropores and mesopores. The chemical activation significantly increased the hydrophobicity of the adsorbent, creating CSAC with a much better adsorption capacity for crude oil removal, having a maximum adsorption capacity of 4840.0 mg/g and the highest percentage of crude oil removal at 99.9985%, as proven by batch experiments for different adsorbent dosages. The batch experimental results indicated that the percentage of crude oil removal increased with an increase in adsorbent dosage and contact time. Based on the correlation coefficients (R²) values (close to unity), it was generally observed that the plots match the Freundlich isotherm better than the Langmuir isotherm model. These findings have made the synthetic CSAC an attractive, useful, and environmentally friendly adsorbent.

Adsorption of amitriptyline from aqueous solutions using magnetic graphene-based material: Isotherm, kinetics, and thermodynamic study

Amitriptyline (AMT) is an antidepressant often found in water environments. Due to its toxicity, in this work, AMT adsorption was proposed using graphene oxide (GO) and magnetic GO (GO·Fe3O4 1:1). The adsorbent characterizations were accomplished by FTIR, SEM, EDS, Raman spectroscopy, XRD, and VSM revealed the typical characteristics of the pristine GO and GO·Fe3O4 1:1. In the batch adsorption study, GO·Fe3O4 1:1 showed the highest adsorption capacity (91.84 mg g−1) and removal percentage (92 %) (at pH = 9.0, C0 = 50.0 mg L−1, adsorbent dosage = 0.5 g L−1, the temperature at 293 ± 1.00 K). Moreover, the Sips model showed the best adjustment for isothermal experimental data. This model suggests that the adsorption occurs at heterogeneous surfaces when the qs value increases with the increase in temperature (from 235.57 mg g−1 at 20 ºC to 463.34 mg g−1 at 50 ºC). The thermodynamic study confirms that AMT adsorption onto GO·Fe3O4 1:1 is a spontaneous and endothermic process (ΔH = 32.75 kJ mol−1). Elovich kinetic model presented the best adjustment for experimental data and showed that the adsorption rate (α) and surface coverage constant (β), decrease with the increase of the adsorbate dosage. Additionally, the ionic strength study reveals that a high concentration of NaCl (1.0 M) decreases the qe to 25.74 mg g−1. Lastly, after five consecutive adsorption/desorption cycles, the removal percentage of GO·Fe3O4 1:1 remained elevated (79 %). Overall, this paper reports the efficiency of GO·Fe3O4 1:1 on AMT removal, in addition to investigating the several variables involved in this adsorption.

Enhanced passivation of lead and cadmium from contaminated farmland using biochar with tailored pore properties: Performance and mechanisms

The porous biochar (PBCPB) was prepared by one-step KHCO3-activated pyrolysis of corn stalks, which showed excellent passivation properties for Pb/Cd in soil (48.99 % or 46.74 %). Characterization results revealed that the PBCPB possessed a dense and network-like pore structure with a huge specific surface area of 1342.07 m2/g, which was conducive to the passivation of Pb/Cd. Batch experiments showed that PBCPB had excellent adsorption properties with the maximum absorption capacity of 117.61/48.24 mg/g. After 30 d of remediation, the bioavailable-Pb/Cd contents in 5.0 % of PBCPB treatment were reduced by 47.06 % and 58.42 %, respectively. The speciation transformation results uncovered that the contents of unstable Pb/Cd components gradually decreased with the increase of PBCPB dosages, ultimately transforming into stable residual components. In addition, the PBCPB could effectively increase the contents of soil available nutrients and enhance functional enzyme activities, which contributed to promoting the growth of cucumber seedlings. Meanwhile, PBCPB strongly alleviated the oxidative damage of Pb/Cd to cucumber seedlings by significantly reducing the Pb/Cd accumulation and antioxidant oxidase activity of cucumber seedlings. Furthermore, precipitation, complexation, as well as cation-π interaction were the primary passivation mechanisms of PBCPB for Pb/Cd. Overall, the study provided a reasonable design of porous carbon-based materials for the remediation of Pb/Cd-contaminated soil.

Erenumab escalation in migraine - double dose without additional benefit - a retrospective experience.

Erenumab is a monoclonal antibody specifically targeting the CGRP-receptor. Several studies showed efficacy and safety in patients with migraine. Less is known regarding dosage increase, especially in a difficult to treat patients. The aim of the study is to evaluate the increased dosage under real world conditions with particular focus on 70mg non-responders. In a retrospective analysis, patients treated in tertiary headache centers (Halle or Jena, Germany) receiving 70mg erenumab for at least 3 months with a dosage increase to 140mg were analyzed. Data were evaluated regarding headache days, intake of acute medication, previous prophylaxis, and medication overuse. Baseline and all treatment intervals were determined as three-month periods. Datasets of 52 migraine patients (90.4% women) aged between 22 and 78 years (mean 50.4 years, SD 12.1 years) were analyzed. At baseline (mean headache-days 15.67 ± 6.37) 51.9% met criteria for chronic migraine and 56% were currently overusing acute medication. While therapy with 70mg showed significant improvement in headache days and 50% response, further improvement was not achieved for therapy escalation to 140mg. The same applies to the secondary endpoints and covers the entire study population as well as the subgroups of chronic and episodic migraine. The 50% response of the 70mg non-responders for escalation was only 5.14%. In this difficult-to-treat patient cohort we reconfirmed the effectiveness of erenumab, but could not detect any additional benefit for a dosage escalation from 70mg to 140mg erenumab.

Study on the effect of deformation and strength characteristics of microencapsulated phase change materials on modified silty clay under dry and wet cycles

To prevent the cracking of silty clay under cyclic wet-dry cycling (W-D), which leads to the increase of deformation and strength attenuation of silty clay, microencapsulated phase change material (mPCM) was used to improve it. The deformation and strength characteristics of silt with different dosages (1 %, 2 % and 4 %) of mPCM and their changing patterns were analyzed and studied by indoor compaction test, crack observation test, consolidation test and straight shear test, and compared with silt without modifier. The results showed that with the increase of mPCM dosage, the optimum water content of silt and the maximum dry density decreased. A 2 % dosage of mPCM inhibited the development of silty clay cracks, reduced crack width and deformation, and increased the compression modulus of the soil samples by nearly 2.3 times. Under dry and wet cycling conditions, the cohesion decay of silty clay is greater than the angle of internal friction. The addition of 2 % mPCM significantly increased the shear strength of silty clay, cohesion by nearly 2.1 times, and internal friction angle by 1.4 times. The mPCM inhibits crack development mainly by regulating the internal temperature field of soil samples, thus improving soil strength. This study provides a reference for inhibiting soil cracking from a new temperature perspective.

Plant-soil hydraulic interaction and rhizosphere bacterial community under biochar and CO2 enrichment

The increasing atmospheric CO2 concentration is a global concern that affects the plant-bacteria-soil system. Previous studies have investigated plant growth and bacteria activity under CO2 enrichment. However, the effects of coupled elevated CO2 and biochar amendment on the interactions of soil and medicinal plants are not well understood. This study aims to investigate the medicinal plant-soil hydraulic interactions and rhizosphere bacteria communities under coupled CO2 enrichment and biochar conditions. Two levels of CO2 concentration (400, 1000 ppm) and two biochar dosages (3%, 5% by mass) were considered. Pseudostellaria heterophylla was used as the tested medicinal plant. During plant growth, coupled CO2 enrichment and biochar at 3% and 5% dosage increased the volumetric water content at a matric suction of 33 kPa by 97% and 82% respectively, which indicates enhanced water retention. The transpiration rate of P. heterophylla was slightly reduced by 11–30% with an increase in biochar dosage due to higher total suction, while it was significantly reduced by up to 57% due to CO2 enrichment. In the rhizosphere of P. heterophylla, elevated CO2 (1000 ppm) coupled with 3% biochar dramatically increase the relative abundance of Thaumarchaeota, which played an important role in C and N cycles. Moreover, coupled CO2 enrichment and biochar addition resulted in the highest bacterial richness, while 3% biochar at ambient CO2 induced the highest bacterial diversity. This study provides a basis for understanding the medicinal plant-bacteria-soil system under CO2 enrichment and biochar conditions.

Articulate Chemotherapeutic Strategies for the Development of Effective Drugs against a Fatal Disease, Visceral Leishmaniasis.

Visceral Leishmaniasis (VL) control relies mainly on chemotherapy in the absence of no effective vaccines. However, available anti-VL drugs are limited in number, having toxicity issues, adverse reactions, low efficacy, and resistance observed against antileishmanial. A significant decrease in efficacy (~tenfold increase in dosage and duration) was reported against the usual treatment with Pentavalent antimonials (the most recommended antileishmanial drug discovered 90 years ago). Amphotericin B is the second line of treatment but limits wider use due to its high cost. Pentamidine is another anti-VL drug, but its therapeutic efficacy has decreased significantly in different areas. These conventional therapeutics for VL have become almost outdated due to a significant increase in therapeutic failure in terms of percentage. Due to this, the search for an effective future anti-VL drug spans several decades, and now it is in high demand in the current situation. Some conventional therapeutics are modified, but they are also not satisfactory. Therefore, this article aimed to discuss conventional and modified therapeutics while emphasizing innovative chemotherapeutic measures against VL that could speed up the slow pace of antileishmanial drugs and overcome the drug resistance problem in the future.

Assessment of Ground Tyre Rubber Impact on Stiffness Modulus and Cracking Resistance of Bituminous Mixtures

Abstract The objective of this study was to evaluate and characterize the performance of ground tire rubber (GTR) modified dense graded asphalt mixtures to recommend a suitable GTR content to produce a mix that provides superior pavement performance characteristics. The research effort encompassed investigation of stiffness and cracking resistance of six dense graded asphalt mixtures, including one conventional and five modified mixes covering 42 samples. Addition of GTR using wet process showed decrease in stiffness during loading. Cracking resistance of GTR modified mixtures increased with higher levels of dosages regardless of the base binder. An increase in the GTR dosage from 0 to 10% did not result in a significant change in fracture energy but a further increment to 25% increased the fracture energy. The laboratory Results indicated that 10% GTR was showed as the optimal content for the stiffness modulus and 25 % GTR as better content that provides better cracking resistance.

Monocomponent Biosorption of Copper Ions (II) onto Nanocrystalline Cellulose from Coconut Husk Fibers

Introduction: Nanocrystalline cellulose (NCC) is one of the most suitable cellulose derivatives for the treatment of wastewater. Various agricultural wastes have been used for the extraction of NCC. Coconut wastes have been widely studied as potential adsorbents for the removal of pollutants, including dyes and heavy metals. Methods: In this work, nanocrystalline cellulose (NCC) was successfully isolated from coconut husk fibers through alkaline pretreatment accompanied by sulfuric acid hydrolysis. Then, the ability of NCC to adsorb Cu2+ from aqueous solution in batch studies was investigated. Results: Results indicated that the optimal hydrolysis parameters were achieved at 50° C for 45 min with 64% sulfuric acid to extract NCC as rod-like particles with diameters between 4-10 nm. The potential of NCC as a biosorbent to remove copper ions (Cu2+) from aqueous solution was investigated in terms of batch mode and maximum adsorption capacity (qm) of 79.491 mg/g of Cu2+. The adsorption efficiency of Cu2+ions increased with an increase in the adsorbent dosage, decreased with an increase in the initial concentration of contaminant, and increased with the contact time. Under optimal conditions, adsorption kinetic followed a pseudo-second-order kinetic model and the adsorption isotherm fitted most closely with the Langmuir model. Conclusion: According to a literature review, NCC from coconut husk fibers has not been used for the adsorption of heavy metals, mainly copper ions. This study shows that NCC from coconut husk fibers can be used as a low-cost and environmentally friendly adsorbent for the removal of Cu2+ from aqueous solutions.

Radiolytic Effects on Biological and Abiotic Amino Acids in Shallow Subsurface Ices on Europa and Enceladus.

Europa and Enceladus are key targets to search for evidence of life in our solar system. However, the surface and shallow subsurface of both airless icy moons are constantly bombarded by ionizing radiation that could degrade chemical biosignatures. Therefore, sampling of icy surfaces in future life detection missions to Europa and Enceladus requires a clear understanding of the necessary ice depth where unaltered organic biomolecules might be present. We conducted radiolysis experiments by exposing individual amino acids in ices and amino acids from dead microorganisms in ices to gamma radiation to simulate conditions on these icy worlds. In the pure amino acid samples, glycine did not show a detectable decrease in abundance, whereas the abundance of isovaline decreased by 40% after 4 MGy of exposure. Amino acids in dead Escherichia coli (E. coli) organic matter exhibited a gradual decline in abundances with the increase of exposure dosage, although at much slower rates than individual amino acids. The majority of amino acids in dead A. woodii samples demonstrated a step function decline as opposed to a gradual decline. After the initial drop in abundance with 1 MGy of exposure, those amino acids did not display further decreases in abundance after exposure up to 4 MGy. New radiolysis constants for isolated amino acids and amino acids in dead E. coli material for Europa/Enceladus-like conditions have been derived. Slow rates of amino acid destruction in biological samples under Europa and Enceladus-like surface conditions bolster the case for future life detection measurements by Europa and Enceladus lander missions. Based on our measurements, the "safe" sampling depth on Europa is ∼20 cm at high latitudes of the trailing hemisphere in the area of little impact gardening. Subsurface sampling is not required for the detection of amino acids on Enceladus-these molecules will survive radiolysis at any location on the Enceladus surface. If the stability of amino acids observed in A. woodii organic materials is confirmed in other microorganisms, then the survival of amino acids from a potential biosphere in Europa ice would be significantly increased.

Modified Halloysite as an Adsorbent for the Removal of Cu(II) Ions and Reactive Red 120 Dye from Aqueous Solutions.

The adsorption of copper ions and Reactive Red 120 azo dye (RR-120) as models of water pollutants on unmodified halloysite (H-NM), as well as halloysites modified with sulfuric acid (H-SA) and (3-aminopropyl)triethoxysilane (H-APTES), was investigated. The results showed that adsorption of both the adsorbates was pH-dependent and increased with the increase in halloysite dosage. The adsorption kinetics were evaluated and the results demonstrated that the adsorption followed the pseudo-second-order model. The adsorption isotherms of Cu(II) ions and RR-120 dye on the halloysites were described satisfactorily by the Langmuir model. The maximum adsorption capacities for the Cu(II) ions were 0.169, 0.236, and 0.507 mmol/g, respectively, for H-NM, H-SA, and H-APTES indicating that the NH2-functionalization rather than the surface area of the adsorbents was responsible for the enhanced adsorption. The adsorption capacities for RR-120 dye were found to be 9.64 μmol/g for H-NM, 75.76 μmol/g for H-SA, and 29.33 μmol/g for H-APTES. The results demonstrated that APTES-functionalization and sulfuric acid activation are promising modifications, and both modified halloysites have good application potential for heavy metals as well as for azo dye removal.

Experiments and kinetic modeling of the sorbitol dehydration to isosorbide catalyzed by sulfuric acid under conditions of non-constant volume

Isosorbide is a novel bio-based material, derived as a secondary dehydration product of sorbitol. This work focuses on the kinetics of sulfuric acid-catalyzed dehydration of sorbitol under conditions of non-constant volume. Herein, the effects of stirring rate, catalyst dosage, reaction temperature, and reaction time on the dehydration reaction of sorbitol were investigated. The yield of isosorbide up to 77.13% was obtained after 1.5 hours of reaction time under conditions of 2 kPa, 1.0% (mass) catalyst dosage, and 413.15 K. Based on the sorbitol dehydration reaction mechanism and a simplified reaction network, a kinetic model was developed in this work. A good agreement was accomplished between kinetic modeling and experiments between 393.15 and 423.15 K. The fitting results indicate that side reactions with higher activation energy are more affected by reaction temperatures, and the main side reaction that influences the selectivity of isosorbide is the oligomerization reaction among the primary dehydration products of sorbitol. The model fitting of the catalyst amounts effect shows that the effective concentration of sulfuric acid would be reduced with the increase of dosage due to the molecular agglomeration effect. Hopefully, the kinetic experiments and modeling results obtained in this work will be helpful to the design and optimization of the industrial sorbitol dehydration process.

Study on the effect of sodium removal from citric acid pretreated red mud on the physical properties of red mud.

Red mud is a highly alkaline solid waste discharged from the alumina industry, and its high sodium content is the key factor limiting its wide utilization. Therefore, effective control of the "frosting" phenomenon during the application of red mud has received significant attention. In this study, the changes of particle size, phase, morphology, and pore size of red mud after sodium removal with different amounts of citric acid pretreatment were investigated. The single-factor experiment shows that the Na+ leaching rate is 86.33% under a citric acid dosage of 15%, liquid-to-solid ratio of 7mL/g, leaching temperature of 80°C, stirring speed of 300rpm, and leaching time of 10min. The leachate is characterized through X-ray diffraction (XRD), scanning electron microscopy (SEM), and Brunauer-Emmett-Teller (BET) surface area analysis. The results reveal that Na+ mainly exists in a combined state in the form of cancrinite. With the increase of citric acid dosage, red mud agglomerates, calcite, and cancrinite are dissolved, and new phases such as calcium oxalate and magnesium aluminum hydroxide are formed. The specific surface area, pore volume, and pore diameter show irregular changes with the increase in the citric acid dosage. Citric acid pretreatment can effectively reduce the sodium content in red mud, the treatment cost of leaching solution is low, and the leaching residue is neutral, which is helpful to promote the practical application of red mud.

Kinetics and equilibrium studies on the adsorptive removal of Nile red dye from aqueous solution using serpentine clay

AbstractThe current research highlighted the usage of serpentine clay to remove Nile red dye from an aqueous solution. At first serpentine clay minerals were analyzed by various analytical techniques like Fourier transform infrared spectroscopy (FTIR), X ray diffraction (XRD), and thermal gravimetric analysis (TGA) analysis. From the characterization results it was found that the clay was determined to be a separate group. Sorption studies investigated the impacts of adsorbent dosage, initial pH, initial dye concentration, and temperature on Nile red color elimination. From the test results it was found that the capacity of adsorption was seen to increase from 32.4 mg/g to a high value of 43.8 mg/g by raising the pH value from 2 to 6. Adsorption on serpentine clay decreased from 234.7 to 33.2 mg/g due to an increase in the adsorbent dosage. The removal capacity of Nile red dye increased from 12.2% to 88.5% with the rise in the adsorbent dosage. This rise in the Nile red dye removal may be observed due to the increase in the area as well as the pore volume of the surface. Experimental study was carried out to study the effect of initial concentration of adsorbate on adsorption at a pH of 6, adsorbent dosage of 3 g/L, and at a temperature of 28°C. The removal efficiency of the Nile red dye was reduced from 96.7% to 42.6%. To determine the temperature effect on the removal of Nile red dye by the clay, the initial pH value was set to 6, and the temperature was set at 28, 38, 48, and 58°C. Without reaching the equilibrium conditions, at a time of 30 min, the removal efficiency of dye rises from 60% to 81% due to the temperature rise. The experimental findings indicated that the adsorption of the dye on the clay followed the “Langmuir adsorption” isotherm rather than the Freundlich adsorption isotherm. Adsorption on clay minerals follows the pseudo‐second‐order adsorption kinetics compared to pseudo‐first‐order adsorption kinetics.

The association between rs6859 in NECTIN2 gene and Alzheimer's disease is partly mediated by pTau.

Emerging evidence suggests a connection between vulnerability to infections and Alzheimer's disease (AD). The nectin cell adhesion molecule 2 (NECTIN2) gene coding for a membrane component of adherens junctions is involved in response to infection, and its single nucleotide polymorphism (SNP) rs6859 was significantly associated with AD risk in several human cohorts. It is unclear, however, how exactly rs6859 influences the development of AD pathology. The aggregation of hyperphosphorylated tau protein (pTau) is a key pathological feature of neurodegeneration in AD, which may be induced by infections, among other factors, and potentially influenced by genes involved in both AD and vulnerability to infections, such as NECTIN2. We conducted a causal mediation analysis (CMA) on a sample of 708 participants in the Alzheimer's Disease Neuroimaging Initiative (ADNI). The relationship between rs6859 and Alzheimer's disease (AD), with AD (yes/no) as the outcome and pTau-181 levels in the cerebrospinal fluid (CSF) acting as a mediator in this association, was assessed. Adjusted estimates from the probit and linear regression models were used in the CMA model, where an additive model considered an increase in dosage of the rs6859 A allele (AD risk factor). The increase in dose of allele A of the SNP rs6859 resulted in about 0.144 increase per standard deviation (SD) of pTau-181 (95% CI: 0.041, 0.248, p<0.01). When included together in the probit model, the change in A allele dose and each standard deviation change in pTau-181 predicted 6.84% and 9.79% higher probabilities for AD, respectively. In the CMA, the proportion of the average mediated effect was 17.05% and was higher for the risk allele homozygotes (AA), at 19.40% (95% CI: 6.20%, 43.00%, p<0.01). The sensitivity analysis confirmed the evidence of a robust mediation effect. This study reported a new causal relationship between pTau-181 and AD. We found that the association between rs6859 in the NECTIN2 gene and AD is partly mediated by pTau-181 levels in CSF. The rest of this association may be mediated by other factors. Further research, using other biomarkers, is needed to uncover the remaining mechanisms of the association between the NECTIN2 gene and AD.

Hydroxyl-aluminum pillared bentonite enhanced Mn(II) removal by chlorine oxidation

Al-PILC was used to catalyze the chlorine oxidation of Mn(II) in aqueous solution. The effects of various catalysts, catalyst dosage, chlorine dosage, pH value, temperature and organic content on the oxidation process were investigated. Results show that 1.5 mg/L chlorine can quickly oxidize Mn(II) from 0.5 mg/L to less than 0.04 mg/L with 10 mg/L Al-PILC. Using catalysts with higher porosity and higher SA, increase in chlorine concentration, increase in catalyst dosage, higher pH, and higher temperature can significantly enhance the rate of Mn(II) catalytic oxidation. The Mn(II) oxidation process includes the homogeneous oxidation, catalytic oxidation on the surface of the catalysts and self-catalytic oxidation produced by the newly produced MnOx. Al-PILC surface provides active sites for chlorine oxidation Mn(II) in the water, and also provides binding sites for the newly produced MnOx, which has higher catalytic activity and thus has an self-catalytic oxidation effect. The higher the porosity and SA of Al-PILC, the more catalytic oxidation active sites and loading sites, and the better the catalytic oxidation effect. The study promotes the understanding of chlorine catalyzed oxidation Mn(II) in aqueous solution, but also provide important guide to study newly efficient catalysts to oxidize Mn(II) with chlorine in aqueous solution.

Numerical Integration Study of Penetration and Blasting Damage for Composite Underground Protective Structure with Reinforcement Layers

In response to the increasing threat of powerful earth-penetrating weapons, underground protective structures typically employ composite structural systems with reinforced steel layers. However, current numerical studies often simplify the entire structural system to plain concrete when assessing damage effects, and penetration and blasting processes are treated separately using a restart method. In this paper, we adopt an integrated simulation approach to analyze the resistance performance of composite protective structures with reinforcement layers. The results reveal significant differences in failure modes between plain concrete and reinforced concrete protective structures. The diameter of the steel bars and the spacing between mesh layers notably impact the penetration and blasting damage. Based on the results of a parameter analysis, we propose a method for optimizing the design of reinforcements in composite underground protective structures. The results of the study show the following: (1) The penetration and blast damage patterns of EPWs on plain concrete and composite protective structures with reinforcing mesh are significantly different. Compared to the plain concrete layer, the composite protection structure can effectively resist the damage of EPWs. (2) With the increase in reinforcement diameter, the decrease in reinforcement mesh spacing, and the increase in reinforcement dosage, the penetration depth gradually decreases; the amount and range of the blast damage also decrease accordingly. (3) Under the condition of the same reinforcement ratio, reducing the number of layers of reinforcement mesh, increasing the diameter of reinforcement, and configuring the reinforcement on the top of the protective structure as much as possible can improve the performance of the protective layer against penetration. At the same time, the reasonable arrangement of the reinforcement mesh can also enhance the ability of the protective structure to resist blasting damage.

A single-step crystallization process to remove potassium from sodium aluminate solution

The high concentration of potassium in sodium aluminate solution seriously threatens the seed precipitation process and reduces the quality of alumina products, but the separation of potassium is quite difficult due to the similar chemical properties between potassium and sodium ions. In this work, a novel single-step double salt crystallization (SDSC) process with low energy consumption was proposed to remove potassium from the concentrated sodium aluminate solution using sodium sulfate, and the corresponding removal performance, kinetics and mechanism were studied. The potassium concentration decreases with the increase of additive dosage and reaction temperature, while the high caustic alkali concentration hinders the potassium removal. At 70 °C, the SDSC process exhibits a rapid crystallization and reaches an equilibrium within 60 min because of the low activation energy and weak bonding of 3 K2SO4·Na2SO4·9H2O. Under the optimum conditions, the potassium removal efficiency can achieve 85.68 %, and the potassium concentration is reduced from 120 g∙L−1 to 24.54 g⋅L−1. Finally, a cyclic utilization pathway was obtained to economically and effectively remove potassium from the sodium aluminate solution.

Therapy duration and improvement of ventricular function in de novo heart failure: the Heart Failure Optimization study.

In patients with de novo heart failure with reduced ejection fraction (HFrEF), improvement of left ventricular ejection fraction (LVEF) is expected to occur when started on guideline-recommended medical therapy. However, improvement may not be completed within 90 days. Patients with HFrEF and LVEF ≤ 35% prescribed a wearable cardioverter-defibrillator between 2017 and 2022 from 68 sites were enrolled, starting with a registry phase for 3 months and followed by a study phase up to 1 year. The primary endpoints were LVEF improvement > 35% between Days 90 and 180 following guideline-recommended medical therapy initiation and the percentage of target dose reached at Days 90 and 180. A total of 598 patients with de novo HFrEF [59 years (interquartile range 51-68), 27% female] entered the study phase. During the first 180 days, a significant increase in dosage of beta-blockers, renin-angiotensin system inhibitors, and mineralocorticoid receptor antagonists was observed (P < .001). At Day 90, 46% [95% confidence interval (CI) 41%-50%] of study phase patients had LVEF improvement > 35%; 46% (95% CI 40%-52%) of those with persistently low LVEF at Day 90 had LVEF improvement > 35% by Day 180, increasing the total rate of improvement > 35% to 68% (95% CI 63%-72%). In 392 patients followed for 360 days, improvement > 35% was observed in 77% (95% CI 72%-81%) of the patients. Until Day 90, sustained ventricular tachyarrhythmias were observed in 24 wearable cardioverter-defibrillator carriers (1.8%). After 90 days, no sustained ventricular tachyarrhythmia occurred in wearable cardioverter-defibrillator carriers. Continuous optimization of guideline-recommended medical therapy for at least 180 days in HFrEF is associated with additional LVEF improvement > 35%, allowing for better decision-making regarding preventive implantable cardioverter-defibrillator therapy.

Rheology of binary cement paste system blended with silica fume and alccofine

&lt;p&gt;The flow properties of the binary cement paste system added with supplementary cementitious materials, effect of polycarboxylate based superplasticizer dosage and their influence on the yield stress and the plastic viscosity were studied. The cementitious materials under the study are silica fume and alccofine. Both the plain cement and the binary cement paste system were considered and tested. A comparative study between the plain cement paste without any additions, silica fume blended cement paste and alccofine blended cement paste was performed. The addition of cementitious materials varies in the range 10%, 20% and 30% and the superplasticizer dosage varies in the range 0.5%, 1.0%, 1.5%, 2%, 2.5% and 3% in the mini-slump flow test and the saturation point was determined to be 2% in both the cases of silica fume and alccofine. The setting time and compressive strength testing on the cement paste considered the superplasticizer dosage up to saturation point. The flow characteristics are broadly the same among the binary paste systems. The setting time results indicated the increase in setting time with increase in cementitious additions and with increase in superplasticizer dosage. The higher percentage substitution of cement with silica fume and alccofine resulted in decrease in compressive strength due to the simultaneous acceleratory and retarding effects of cementitious additions and the superplasticizer. The results of the rheological measurements revealed that silica fume possess greater elasticity than that of the alccofine which possess greater yield stress and plastic viscosity.&lt;/p&gt;