Particle Dosage Research Articles

Biosynthesis of gold nanoparticles from Martynia annua aqueous leaves extract, its antioxidant potential and antimicrobial ability against selected wound pathogens

The field of nanotechnology has great potential within the realm of modern nanoscience and technology. Ecologically responsible nanoparticle production requires the careful selection of a solvent that is ecologically acceptable, together with the use of reducing and stabilizing chemicals that are also environmentally beneficial. The utilization of gold nanoparticles has been widely investigated in the fields of separation sciences and illness diagnosis for biological purposes. The objective of this study is to synthesize gold nanoparticles utilizing a Water-based Leaf Extract from the Martynia annua Plant in an ecologically sustainable manner. X-ray diffraction, Fourier transform infrared spectroscopy (FTIR), and scanning electron microscopy (SEM) were employed to analyze the morphological characteristics, stability, and crystalline structure of the produced nanoparticles. The experimental results validate the commencement of the gold ion reduction process by the detected change in color of the reaction mixture to a deep purple colour. Moreover, the synthesis was confirmed by the use of UV–visible spectrometry, within the wavelength region of 584 nm. The zeta potential of the produced nanoparticles is reported to be −31 mV, while the average diameter of the particles is about 21 nm. The synthesized particles exhibit significant antioxidant capacity in comparison to the standard. Further AuNPs shows strong antibacterial potential against Escherichia coli, Staphylococcus aureus, Streptococcus sp, Bacillus subtilis, and Enterococcus sp was 53.94 µg/mL, 78.02 µg/mL, 55.47 µg/mL, 55.83 µg/mL, and 95.24 µg/mL respectively Synthesized particles demonstrate substantial cytotoxicity against A549 human lung cancer cells and it shows the inhibitory concentration at 20 µg/ml. The results indicated a significant decrease in cell viability, which was directly linearly related to the dosage of particles. The Martynia annua plant mediated gold nanoparticles exhibit potent antioxidant and antibacterial properties effectively combating specific wound infections.

Optimized preparation of Ni-Febm bimetallic particles by ball milling NiSO4 and iron powder for efficient removal of triclosan

The excessive usage and emissions of triclosan (TCS) pose a serious threat to aquatic environments. Iron-based bimetallic particles (Pd/Fe, Ni/Fe, and Cu/Fe, etc.) were widely used for the degradation of chlorophenol pollutants. This study proposed a novel synthesis method for the preparation of Ni/Fe bimetallic particles (Ni-Febm) by ball milling microscale zero valent iron ZVI (mZVI) and NiSO4. Ball-milling conditions such as ball-milling time, ball-milling speed and ball-to-powder ratio were optimized to prepare high activity Ni-Febm bimetallic particles. During the ball-milling process, Ni2+ was reduced to Ni0 and formed a coupled structure with ZVI. The amount of Ni0 on ZVI significantly affected the activity of Ni-Febm bimetallic particles. The highest activity Ni-Febm bimetallic particles with Ni/Fe ratio of 0.03 were synthesized under optimized conditions, which could remove 86.56% of TCS (10 μM) in aerobic aqueous solution within 60 min. In addition, higher particle dosage, lower pH condition and higher reaction temperature were more conducive for TCS degradation. The higher corrosion current and lower electron transfer impedance of Ni-Febm bimetallic particles were the main reasons for its high activity. The hydrogen atom (•H) on the surface of Ni-Febm bimetallic particles was mainly contributed to the removal of TCS, as reductive transformation products of TCS were detected by LC-TOF-MS. Notably, a small amount of oxidation products were discovered. The total dechlorination rate of TCS was calculated to be 39.67%. After eight reaction cycles, the residual Ni-Febm bimetallic particles could still degrade 28.34% of TCS within 6 h. Low Ni2+ leaching during reaction indicated that Ni-Febm bimetallic particles did not pose potential environmental risks. The prepared environmental-friendly Ni-Febm bimetallic particles with high activity have great potential in the degradation of other chlorinated organic compounds in wastewater.

Promoting mechanism of nitrogen removal by Fe3O4 magnetic particles during the start-up phase in sequencing batch reactor.

In this paper, a magnetic sequencing batch reactor (SBR) was constructed, and the influence rule of magnetic particle dosing performance of denitrification was investigated. The diversity, structure, and potential functions of the microbial community were comprehensively explored. The results showed that the particle size and the dosage of Fe3O4 magnetic particles were the main parameters affecting the sedimentation performance of activated sludge. The start-up phase of the SBR reactor with Fe3O4 magnetic particles was 5days less than the control. Moreover, total nitrogen removal efficiency during the start-up phase was improved, with the maximum value reaching 91.93%, surpassing the control by 9.7% with the Fe3O4 dosage of 1.2g L-1. In addition, the activated sludge concentration and dehydrogenase activity were improved, compared to the control. High-throughput sequencing showed that the denitrifying bacterium Saccharimonadales dominated the reactor and was enriched by magnetic particles. According to predicted functions, the abundance of genes for denitrification increased with the addition of magnetic particles, suggesting the capacity of nitrogen removal was enhanced in the microbial community. Overall, the Fe3O4 magnetic particles provide great potential for enhanced wastewater nitrogen removal.

Electro-induced carbon black particle electrodes for sustainable tetracycline degradation

For the purpose of degrading tetracycline (TC), a three-dimensional electro-oxidation (3D EO) system using particle electrodes of carbon black (CB) and polytetrafluoroethylene (PTFE) was developed. The CB-PTFE particles fabricated at a CB/PTFE mass ratio of 3:2 and calcination time of 60 min exhibited the high performance for TC removal, as well as low energy consumption and high mechanical strength. TC removal efficiency reached 95% within 15 minutes, driven by a pseudo-first-order reaction with a rate constant of 0.20 min−1. The process incurred an energy consumption of 20.31 kWh/m3. The surface characterizations indicated that the CB-PTFE particles possessed excellent catalytic properties for H2O2 production. Despite the substantial influence of voltage and particle dosage on performance, the system demonstrated consistently high efficiency in TC removal regardless of solution pH within the range of 3–11. Quenching experiments and probe experiments using benzoate suggested that the surface-bound hydroxyl radicals (•OH (ads)) dominated (64.7%) the oxidation of TC in the 3D CB-PTFE EO system. The •OH (ads) was produced by the reduction of H2O2 on the particle surface. Products examination by LC-MS-MS confirmed a degradation pathway of TC by •OH attacking. These findings indicate that the CB-PTFE EO system has unique advantages and potentials in treating antibiotics due to its high oxidizing capacity, a wide range of applicable pH, no chemical adding, and self-cleaning.

Study on the hydration reaction and pore structure of ecologically recycled mortar with corn cob aggregates

Ecologically recycled mortar with corn cob aggregates becomes a research hotspot. However, corn cobs consist of organic materials which have a negative impact on the hydration process of cement. Therefore, a knowledge of the effects of corn cob particle dosage on the hydration reaction process and microscopic pore is important. In this study, nuclear magnetic resonance (NMR) was used to quantitatively and visually observe the hydration reaction of the mortar, and it was found that the addition of corn cob particles resulted in a 22-fold increase in harmful pores and a 20% decrease in pore complexity. Moreover, the effects of corn cob particles on self-shrinkage after the exothermic hydration of mortar was investigated. The result demonstrates that mortar with corn cob particles exhibits a certain degree of plasticity and can bear a certain amount of load, while retaining up to 20% of its deformation energy. Despite the decrease of strength, high admixtures of corn cob particles have excellent thermal insulation properties. This attribute endows corn cob pellet eco-mortar (EM) with the ability to resist external loads, such as those caused by earthquakes and uneven settlement, and thus, provides this material with the potential to be utilized as a wall material.

Preparation and properties of one-component polyurea composite phase change cooling coating for asphalt pavement

To reduce the high-temperature distress of asphalt pavement and alleviate the urban heat island effect, one-component polyurea composite phase change cooling coating was prepared. Through the tests of storage time, curing time, hardness and tensile property, the performance variation of one-component polyurea under different latent curing agent dosage were analyzed. Through the tests of road performance and thermoregulation performance, the change rule of road performance and cooling effect of one-component polyurea composite phase change cooling coating under different amount of phase change particle admixture and coating were analyzed. The results showed that the phase-change cooling coating prepared in this study can meet the requirements of road performance. When the dosage of phase change particles is 20% and the amount of coating is 1.2 kg/m2, the maximum cooling effect of the coating reached 3.7 °C under the simulated indoor conditions and 3.3 °C under the real outdoor environment.

Experimental Investigation of Lanthanum-Modified Reinforced Composite Material for Phosphorus Removal

Adsorption stands as an economically viable, efficient, recyclable, operationally straightforward, cost-effective, and low-sludge method extensively employed for phosphorus removal. In an effort to enhance the adsorption capabilities of the adsorbent, this study employs the rare-earth metal lanthanum in conjunction with the group’s previously researched high-efficiency composite industrial residue phosphorus removal materials (EPRC) for modification, thereby generating lanthanum-modified reinforced composite phosphorus removal materials (La-EPRC). Subsequently, the novel material undergoes static modification, followed by experimental investigations into static and dynamic adsorption for phosphorus removal. Static adsorption experiments reveal optimal phosphorus removal efficiency when the initial phosphorus solution concentration is 20 mgP/L, with a La-EPRC particle dosage of 3 g/250 mL and a temperature of 25 °C. The removal efficiency of phosphorus particles is above 90% within the pH range of 4 to 10. Common coexisting anions in water, including Cl−, SO42−, HCO3−, and CO32−, demonstrate minimal impact on the efficacy of phosphorus removal. La-EPRC demonstrates a robust adsorption stability in both water and hot water environments. In a 2.5 mol/L NaOH solution, effective desorption of La-EPRC particles is observed, facilitating material regeneration. The raw materials for La-EPRC are easily accessible and cost-effective, imparting significant potential for widespread applications.

Mechanical and dynamic mechanical behavior of 3D printed waste slate particles filled acrylonitrile butadiene styrene composites

This study analyses the feasibility of utilizing waste slate particles as a strengthening component in affordable 3D-printed composite materials to address environmental issues associated with waste management. Composite filaments were created by incorporating waste slate particles (5 %, 10 %, and 15 % by weight) into an acrylonitrile butadiene styrene (ABS) matrix and subsequently evaluated for mechanical properties. A twin-screw extruder obtained the composite filaments, while test samples were produced using a 3D printer by fused deposition modelling. The developed composites have a gradual variation in evaluated properties, about an 8 % increment in hardness, and a 40 % increment in flexural and tensile modulus was noted on the inclusion of 15 wt% of waste slate particles in the ABS matrix. The composites filled with 10 wt% and 5 wt% waste slate particles exhibited the maximum flexural strength (65.24 MPa) and tensile strength (42.11 MPa), respectively. These values were 5 % and 8 % higher than those of unfilled ABS. Furthermore, it was shown that the ABS matrix saw a decrease in elongation and impact strength as the dosage of slate particles increased. The fractured surface morphology indicated that filament breaking, filler pullout, and the creation of voids between neighbouring layers were the primary causes of material failure. The dynamic mechanical analysis (DMA) results show the reinforcing effect of slate particles by an increase of storage modulus with 13 % at 35 °C for the composite with 10 wt% slate particles and 20 % for that with 15 wt% slate particles. DMA results analyzed the composite's adhesion factor, degree of entanglement, reinforcement efficiency factor, and effectiveness factor to clarify the reinforcing mechanism of slate particles. The study determines that the most effective utilization of waste slate particles in an ABS matrix is achieved by including 10 wt%. The results of this study enhance the concept of recycling waste slate powder and reveal the potential for their utilization in several industries, including the aerospace, automotive, healthcare, and architectural sectors of 3D printing.

Monitoring Tools and Strategies for Effective Electrokinetic Nanoparticle Treatment

Nanoparticles are increasingly being used by industry to enhance the outcomes of various chemical processes. In many cases, these processes involve over-dosages that compensate for particle losses. At best, these unique waste streams end up in landfills. This circumstance is inefficient and coupled with uncertain impacts on the environment. Pozzolanic nanoparticle treatments have been found to provide remarkable benefits for strength restoration and the mitigation of durability problems in ordinary Portland cement and concrete. These treatments have been accompanied by significant particle losses stemming from over-dosages and instability of the colloidal suspensions that are used to deliver these materials into the pore structure. In this study, new methods involving simple tools have been developed to monitor and sustain suspension stability. Turbidity measurement was introduced to monitor the progress of electrokinetic nanoparticle treatment. This tool made it possible to amend a given dosing strategy in real time while it remains possible to make effective treatment adjustments. By monitoring the particle stability and using pH and electric field controls to avoid suspension collapse, successful electrokinetic treatment dosage strategies were demonstrated using 20 nm NALCO 1056 alumina-coated silica particles. These trials indicated that turbidity measurements could track the visually imperceptible phenomena of particle flocking early on at the inception of its development. Suspensions of these nanoparticles were successfully delivered into 5 cm diameter by 10 cm tall hardended cement paste (HCP) specimens by monitoring fluid turbidity along with the specific gravity and using these values to guide the active management of the treatment dosage and pH. Under this new strategy, these losses were reduced to 5% as compared to the 80% losses associated with other treatment approaches. The relationship between the turbidity and the specific gravity was found to be linear. These plots indicated regions of turbidity and specific gravity that were associated with particle flocking. The tools, guidelines, and strategies developed in this work made it possible to manage efficient (low-particle-loss) electrokinetic nanoparticle treatments by signaling in real time when adjustments to electric field, pH, and particle dosage increments were needed.

Three-Dimensional Numerical Analysis and Operational Optimization of High-Efficiency Sedimentation Tank

The high-efficiency sedimentation tank has a wide range of application prospects in industrial wastewater treatment due to its small footprint, strong resistance to shock loads, and high efficiency. However, the complex flow field distribution inside significantly affects the treatment performance of the high-efficiency tank. In this study, a three-dimensional geometric model of the high-efficiency sedimentation tank was constructed based on an engineering prototype. The corresponding solid–liquid two-phase, whole-process computational fluid dynamics (CFD) model for the high-efficiency sedimentation tank was established using the realizable k-ε turbulent model and the multiple reference frame (MRF) method. The internal structures of the flocculation zone, plug-flow zone, and clarification zone were optimized, and then the influence of operational process conditions on the flocculation treatment performance was investigated. The results indicate that, for the given engineering model, the average turbulent kinetic energy k in the flocculation zone exhibits a trend that initially increases and then decreases with the increase in the diameter and height of the draft tube. The optimal hydraulic conditions for the flocculation zone are achieved when the diameter of the draft tube is 2.5 m and the height is 3.5 m. The average turbulent kinetic energy dissipation rate in the plug-flow/clarification zone tends to decrease first and then increase as the height of the water tunnel and water-retaining weir increases. The optimal hydraulic conditions for the plug-flow and clarification zones are achieved when the height of the water tunnel is 1.0 m and the height of the water-retaining weir is 1.6 m. Under optimal operating conditions (dosage of dense media particles: 40 mg/L, stirring rate: 30 rpm, and inlet velocity: 0.72 m/s), satisfactory overall hydraulic conditions can be achieved throughout the entire high-efficiency sedimentation tank. Comparisons between a high-efficiency settling tank and a conventional clarifier for the treatment of circulating water sewage in a practical implementation reveals that the ballasted high-efficiency settling tank has advantages in terms of high hydraulic loading, high removal efficiency of hardness, small footprint, and low doses of flocculant. This research will provide reference values for the design and operation optimization of high-efficiency sedimentation tanks.

A Technical Feasibility of Aqueous Aerosol Generation Based on the Flashing Jet: Effects of Overheat Degree, Jetting Rate, Jetting Volume, and Liquid Type

AbstractA previously established flashing jet inhaler prototype (FJ prototype) can produce an aqueous aerosol but cannot steadily provide inhalable aerosol (2–5 μm). This study aims to optimize the atomization performance of the FJ prototype and generate inhalable aqueous aerosols. The effects of overheat degree, jetting rate, jetting volume, and liquid type on atomization performance were assessed by determining output aerosol's mass median aerodynamic diameter (MMAD) and aerodynamic particle size distribution. Drug distribution of active ingredients in different liquid types was also measured. A Pari nebulizer was used as a reference device. Our data suggested that MMAD is negatively correlated with the overheat degree and jetting rate, but has no significant relationship with the jetting volume. The effect of jetting rate is weaker than that of the overheat degree. When normal saline was used as the atomization liquid, output aerosol's MMAD at the FJ prototype and Pari nebulizer were 1.98 ± 0.18 and 2.50 ± 0.81 μm, respectively. The addition of a surfactant significantly decreases MMAD both in solution and in suspension, but the suspended particles had no effect on the residual level and atomization performance of the FJ prototype. When ventolin was used as the atomization liquid, the MMAD of the FJ prototype and Pari nebulizer was 2.1 ± 0.2 and 1.7 ± 0.2 μm, respectively, while the fine particle dosage (FPD) in percent of the nominal dose (%ND) was 50.4 ± 3.1 and 53.1 ± 7.2%, respectively. When pulmicort respules was used as the atomization liquid, the MMAD of the FJ prototype and Pari nebulizer was 2.5 ± 0.5 and 4.6 ± 0.2 μm respectively, while the FPD (%ND) was 30.1 ± 5.6 and 58.6 ± 5.1%, respectively. The FJ prototype not only delivers inhalable aqueous aerosol but also has a potential advantage in the atomization of suspension or poorly soluble drugs.

Effect of foam stabilization on the properties of foamed concrete modified by expanded polystyrene

This paper aims to study the modified foamed concrete by mixing expanded polystyrene (EPS) particles. In order to analyze the influence of EPS particle dosage and particle size on the mechanical properties and thermal conductivity of the foamed concrete, the EPS modified foamed concrete was compared with the ordinary foamed concrete. The pore structures of the foamed concrete with and without EPS were characterized and compared by scanning electronic microscopy (SEM), mercury intrusion porosimetry (MIP), and image-pro plus (IPP). The results showed that when large and small size EPS replaced 60% foam, the water absorption of the EPS modified foamed concrete was approximately 38% and 55% lower than that of the ordinary foamed concrete, respectively, with a corresponding 0.13 and 0.5 MPa increase in compressive strength. In addition, the thermal conductivity of the EPS modified foamed concrete was similar to/even slightly lower than that of the ordinary foamed concrete. The addition of EPS in foamed concrete increased the proportion of small connected pores and reduced the proportion of medium and large pores. Overall, the addition of EPS in foamed concrete can effectively improve the stability.

Metallocene Polyolefins Reinforced by Low-Entanglement UHMWPE through Interfacial Entanglements

By introducing low-entanglement UHMWPE, the mechanical properties of polyolefins are improved to varying degrees. For polypropylene, the lack of interaction between UHMWPE and polypropylene results in an unsatisfactory reinforcement effect, and the disentangled state makes it easier for the particles to form defects driven by a chain explosion. In contrast, regarding polyethylene and elastomer containing ethylene segments, low-entanglement UHMWPE plays a better role in reinforcement. A series of measurements including scanning electron microscopy (SEM), rheological measurements, differential scanning calorimetry (DSC), and mechanical measurement were used to investigate the mechanisms for the different enhancement effects. It originates from interdiffusion and entanglement forming of polyethylene segments across the interface, endowing the material with different aggregated and defect structures. For instance, EPDM possesses a higher optimal dosage of UHMWPE particles reflected in good interfacial interdiffusion with UHMWPE particles, leading to significant optimized mechanical performance.

Effects of load and environment on the durability and anti-skid performance of road heat-reflective coating

• Studied the heat-reflective coating of asphalt pavement. • Systematically studied the durability of heat-reflective coating. • Investigated the effect of anti-skid particles on the cooling performance of coating. • Studied the optimal dosage of anti-skid particles. Reducing high temperature rutting on asphalt pavement is of great importance to improve the quality of pavement engineering and road traffic safety. In laboratory and field tests, this study investigates the cooling performance and optimal dosage of heat-reflective coatings. The temperature-change resistances, water stabilities, abrasion resistances, and skid resistances of six colored heat-reflective coatings were studied. Among the differently colored coatings, the red coating demonstrated the best cooling performance, with a maximum cooled temperature of 13.2 °C. The colored heat-reflective coatings showed good temperature-change resistance, water stability, and abrasion resistance. At dosages of 0.35 and 0.55 kg/m 2 , the heat-reflective coating met the specification requirements of skid resistance; meanwhile, the coating added at 0.75 kg/m 2 achieved the highest cooling performance but failed to meet the required skid-resistance standards. After adding anti-skid particles, the skid resistance was improved while the cooling performance was hardly affected. The optimal dosage of anti-skip particles was 0.3 kg/m 2 .

Attenuation pattern of skid resistance of heat reflective coatings under the effect of simulated pavement abrasion

ABSTRACT The cooling performance of heat reflective coatings (HRC) for pavement applications has attracted wide attention. In this study, the cooling performance and bond strength of HRC were investigated and the attenuation pattern associated with the skid resistance of specimens sprayed with different amounts of HRC coating was examined based on four-wheel wear test. Furthermore, an asymptotic model associated with the attenuation of the HRC’s skid resistance was developed for investigating the effects of anti-slip particle gradation and dosage as well as HRC dosage on the skid resistance. The results show that the cooling performance and bond strength of HRC (sprayed amount: 0.8 kg/m2) are 12.4 °C and 1.75 MPa, respectively, and the skid resistance of HRC sprayed with different amounts of HRC was stabilised at approximately 48 BPN after 150,000 abrasion cycles. The attenuation pattern of the skid resistance of the skid-resistant HRC (SHRC) fitted well with the developed asymptotic model, showing a correlation coefficient exceeding 0.99 and an error of less than 5% from the test value. Anti-slip particle gradation (G4), anti-slip particle dosage (0.6 kg/m2) and HRC dosage (0.6 kg/m2) were selected based on the stable value of the skid resistance, and SHRC was developed for pavement applications.

Enhanced biological phosphorus removal in low-temperature sewage with iron-carbon SBR system

ABSTRACT This study proposed an AO-SBR (Anaerobic Aerobic Sequencing Batch Reactor) combined with iron-carbon micro-electrolysis (ICME) particles system for sewage treatment at low temperature and explored the dephosphorisation mechanism and microbial community structure. The experimental results illustrated that ICME particles contributed to phosphorus removal, metabolic mechanism of poly-phosphorus accumulating organism (PAO) and microbial community structure in the AO-SBR system. The optimal treatment effect was achieved under the conditions of pH 7, DO 3.0 mg/L and particle dosage of 2.6 g Fe-C/g MLSS, and the removal rates of COD, TP, NH4 +-N and TN reached 80.56%, 91.46%, 69.42% and 57.57%. The proportion of phosphorus accumulating organisms (PAOs) increased from 4.54% in the SBR system to 10.89% in the ICME-SBR system at 10°C. Additionally, the metabolic rate of PAOs was promoted, and the activities of DHA and ETS both reached the maximum value of 13.34 and 102.88 μg·mg−1VSS·h−1. These results suggest that the ICME particles could improve the performance of activated sludge under low-temperature conditions. This technology provides a new way for upgrading the performance of sewage treatment in the cold area.

Investigation on performance of expansive soil stabilized with fly ash and nano-SiO2

The present paper reported the performance of clayey soil stabilized with fly ash and nano-SiO2by conducting various laboratory experiments. The performance of the stabilized material was studied by performing various geotechnical tests including compaction, consistency limits, unconfined compression strength and California bearing ratio tests. For better understanding of the underlying mechanisms of the samples, experiments like scanning electron microscope and energy dispersive X-ray tests were analyzed. In this study initially, the clayey soil was treated with five different proportions of fly ash, i.e., 10, 15, 20, 25, and 30% by total weight of the dry soil and the optimum value obtained was 20%. Then various percentages of nano-SiO2(i.e., 0.5, 1.0, 1.5, 2.0 and 2.5%)were mixed with the optimum value of fly ash and the performance of the stabilized soil was investigated. From the laboratory tests, the optimum dosage of fly ash and nano-SiO2 particles obtained was 20% and 1.5% respectively. The experimental results concluded that the use of nano-SiO2in the fly ash treated soil enhances the UCS and CBR value significantly.

Rapid preparation of a composite insulating block comprising waste expanded polystyrene (EPS) foam and rice straw

Due to the world’s decreasing energy supply, reducing the energy consumption of building envelopes has become an urgent issue with economic benefits. Rice straw is a generally available agricultural residue. The purpose of this study was to estimate the effects of rapid pretreatment methods and slaked lime on the molding of rice straw insulation blocks and to evaluate the effectiveness of integrating expanded polystyrene (EPS) particle waste with rice straw as building materials to reduce the energy loss in buildings. The pretreatment time was shortened from 6 h to 3 h by mechanical stirring combined with lye soaking. The molding of the insulation block could be improved by the hardening of slaked lime through contrast experiments and electron microscope scanning. Moreover, the influences of the mass ratio of slaked lime to rice straw (RSR) and the dosage of the EPS particles (ωEPS) on the dry apparent density and the thermal conductivity of the insulation blocks were studied. The results showed that the slaked lime would increase the dry apparent density and weight of the insulation block, but the EPS can effectively reduce this negative effect and keep the thermal conductivity of the insulation block below 0.049 W·m-1·K-1. Ultimately, the rapid pretreatment technology was determined to include lye soaking for 3 h and mechanical stirring for 5 min. The material matching ratio scheme was determined to have a ωEPS value of less than 3% and an RSR value equal to 1/7.5.

Modification of hydrophobicity of concrete with nanometer composite particles

With the frequent occurrence of natural disasters nowadays, traditional house construction can no longer be adapted to the current needs of people for building living conditions. Over time, traditional house construction presents deeper cracks, seriously endangering people’s safety. This study mainly discusses the modification of nanocomposite particles on the hydrophobicity of concrete. In view of the current concerns of people, this study uses nanocomposites to fill concrete, change the physical properties of concrete, and greatly reduce the hydrophobic properties of concrete. The experiments were divided into 6 groups, and the hydrophobicity of concrete was discussed by changing the amount of nanocomposite particles and the size of nanocomposite particles. The dosage of the nano-composite particles is 0.05 kg, 0.1 kg, 0.15 kg, 0.2 kg, 0.25 kg, 0.3 kg, keeping the quality of the concrete 1 kg, the diameter of the nano-composite particles is 0.1 mm, 0.2 mm, 0.3 mm, 0.4 mm, 0.5 mm, 0.6 mm, keeping the quality of concrete is also 1 kg. During the experiment, when the amount of nano-composite particles is 0.15 kg, the hydrophobic property of concrete is reduced by 81%, the hydrophilic property of concrete is increased by 19%, and the hydrophilic property of concrete is the best. When the diameter of the nanocomposite particles is 0.1 mm, the hydrophobic property of concrete is reduced by 79%, and the hydrophilic property of concrete is increased by 18%. The experimental results show that when the amount of nano-composite particles is 0.15 kg and the diameter of the nano-composite particles is 0.1 mm, the hydrophobic property of concrete is the lowest, which is most beneficial to the solidification of concrete. In this case, the building can be made stronger.

Research on the Influence of Water Storage Medium on early Planting Performance of Portland Cement Foamed Concrete

Adding sap particle, Portland cement foamed concrete was studied to manufacture a new type of planting material. The pH, porosity, permeable capacity, infiltration rate and water storage were tested for evaluating the performance of foamed concrete. Solid-liquid extraction method and image binaryzation were used to study the pH and porosity of foamed concrete. A kind of self-made permeable device was also used in this paper. It was found that the pH of foamed concrete could be decreased by sap particles absorbed the boric acid solution in 14 d. For the foaming effect of fresh concrete was disturbed by liquid from sap particles, the porosity of foamed concrete was increased and then decreased. Seepage channels could be formed in foamed concrete when sap particles shrunk for releasing liquid and they also would be block for sap particles expanding when water permeated into foamed concrete. The permeable capacity and infiltration rate were decreased with increasing sap particles. The water storage of foamed concrete was fluctuated with sap particles increasing but more than that without sap particles. The optimal dosage of sap particles was 0.3wt% of binder material in this study. At the dosage, the minimal pH of foamed concrete could be obtained and performance of that would be good to plant, such as permeable capacity, infiltration rate and water storage.