Effect Of Solution Concentration Research Articles

Fabrication of 3D Polycaprolactone Macrostructures by 3D Electrospinning.

Building 3D electrospun macrostructures and monitoring the biological activities inside them are challenging. In this study, 3D fibrous polycaprolactone (PCL) macrostructures were successfully fabricated using in-house 3D electrospinning. The main factors supporting the 3D self-assembled nanofiber fabrication are the H3PO4 additives, flow rate, and initial distance. The effects of solution concentration, solvent, H3PO4 concentration, flow rate, initial distance, voltage, and nozzle speed on the 3D macrostructures were examined. The optimal conditions of 4 mL/h flow rate, 4 cm initial nozzle-collector distance, 14 kV voltage, and 1 mm/s nozzle speed provided a rapid buildup of cylinder macrostructures with 6 cm of diameter, reaching a final height of 16.18 ± 2.58 mm and a wall thickness of 3.98 ± 1.01 mm on one perimeter with uniform diameter across different sections (1.40 ± 1.10 μm average). Oxygen plasma treatment with 30-50 W for 5 min significantly improved the hydrophilicity of the PCL macrostructures, proving a suitable scaffold for in vitro cell cultures. Additionally, 3D images obtained by synchrotron radiation X-ray tomographic microscopy (SRXTM) presented cell penetration and cell growth within the scaffolds. This breakthrough in 3D electrospinning surpasses current scaffold fabrication limitations, opening new possibilities in various fields.

Enhancing Cr (VI) Adsorption of Chestnut Shell Biochar through H3PO4 Activation and Nickel Doping.

A high-efficiency nickel-doped porous biochar (PCNi3) has been successfully synthesized from chestnut shell waste via a two-step chemical activation treatment with H3PO4. The influences of microstructure, surface morphology, elemental composition, surface functional groups, specific surface area, porosity, pore-size distribution, and chemical properties of the surface state on the removal of Cr (VI) from water were thoroughly investigated by using XRD, FESEM, FTIR, Raman, BET, and XPS testing methods, N2 adsorption, and XPS testing techniques respectively. The results indicate that the treatment of H3PO4 activation and nickel doping can effectively improve microstructure characteristics, thus promoting Cr (VI) adsorption capacity. The effects of initial solution pH, solution concentration, time, and temperature on remediation are revealed. The Cr (VI) uptake experiments imply that the adsorption curves of PCNi3 fit well with the Freundlich model, the pseudo-second-order kinetic model, and the Elovich model. The adsorption process of PCNi3 can be regarded as a spontaneous endothermic reaction limited by diffusion among particles and porosity. The adsorption mechanisms of PCNi3 are ion exchange, complexation, electrostatic adsorption, and coprecipitation with the assistance of surface active sites, porosity, Ni0 particles, and Ni7P3. With these advantages, PCNi3 reveals an extraordinary Cr (VI) removal capacity and a strong ability to reduce Cr (VI) to Cr (III).

Enhancing Soil Resilience to Climatic Wetting‐Drying Cycles Through a Bio‐Mediated Approach

AbstractClimatic wetting‐drying cycles exacerbated by climate change can trigger several weakening mechanisms in surface soils, potentially leading to instability and failure of slopes and earthen structures. This study proposes a bio‐mediated approach based on microbially induced calcite precipitation (MICP) to increase soil resilience to wetting‐drying cycles. To explore its viability and the underlying mechanisms, we conducted a series of laboratory tests on clayey soil that underwent six wetting‐drying cycles. The tests were conducted with different treatment methods to investigate the effect of treatment sequence and cementation solution concentration. After MICP treatment, the initial evaporation rate, surface crack ratio during drying, and total soil weight loss during rainfall erosion were reduced by up to 32%, 85%, and 90%, respectively. Spraying the cementation solution first in the MICP treatment sequence proves more effective in improving soil water retention capacity. On the other hand, initiating the sequence with the bacterial solution demonstrates a more pronounced effect in reducing soil desiccation cracks and erosion. Microstructure analysis reveals that the content and distribution of CaCO3 precipitation are the major factors controlling the effectiveness of MICP for the cementation of clayey soil. Employing MICP can minimize the carbon footprint and contribute to developing environmentally friendly solutions for soil improvement in regions affected by climatic wetting‐drying cycles.

A simple model of the soil freezing characteristic curve for saline soils with two freezing stages

Soil freezing characteristic curve (SFCC) describes the relationship between unfrozen water and subzero temperature, which is of significance for the simulation of heat, water, salt migration in cold regions. There are two phase transition stages in some saline soils, which is often explained by the phase equilibrium of bulk solution. However, the second phase transition and chemical characteristic of solute are ignored in the current coupling numerical models for freezing-thawing soils. The newest SFCC methods considering abovementioned two items are not applicable to numerical models due to complex calculation or irregularly changeable parameters. To solve those problems, a simple model was proposed in this paper. Firstly, the complete phase diagram of pore solution at icing stage was speculated from published experimental SFCCs of saline soils. Then, the temperatures of saline soils at freezing and eutectic points were quantitative expressed with phase diagram of bulk solution and SFCC of nonsaline soil, and the criteria determining whether single icing stage or icing-eutectic stage occurs in saline soils was proposed. A synthetic index was used to describe the effects of soil matrix and initial solute concentration on the exponent. Only three constant parameters were introduced to reflect the soil matrix effect on phase transition points of pore solution and the influence of chemical characteristic of solute on pore water freezing process. Finally, the model was validated by the experimental data of saline soils and showed good results and ease of use compared to a widely used theorical model for saline soil with single freezing stage and other two models both considering two phase transitions. The work provides a deeper view of freezing process in saline soils and promote the improvement of numerical simulation effect for heat, water and salt migration in seasonal freezing-thawing areas.

The electrochemical corrosion behavior of Ti-5Al-5Mo-5V-1Cr-1Fe titanium alloy with different initial microstructures

The corrosion behavior of Ti-5Al-5Mo-5V-1Cr-1Fe titanium alloy with different initial microstructures was investigated by conducting a series of electrochemical tests. Based on the experimental data, the effects of NaCl solution concentration and corrosion time on the electrochemical polarization curves, corrosion rates, electrochemical impedance spectroscopy (EIS), and impedance of the alloy with two initial microstructures were analyzed. The assessment of the corrosion current density (Icorr) and corrosion rate (CR) for the alloy under different corrosion conditions reveals a general pattern of initial decrease followed by increase in their values with extended corrosion time and elevated solution concentration, whereas the capacitive reactance arc exhibits an opposite trend. For alloys with initial equiaxed microstructures, the Icorr value is 0.1892 μA/cm2, and the CR value is 0.000413 mm/year; these values are lower than those of 1.298 μA/cm2 and 0.002842 mm/year for alloys with initial lamellar microstructures. Whereas the capacitive reactance arc and the impedance value are greater for the titanium alloy with initial equiaxed microstructure. Based on the adsorption kinetics principles, the effects of temperature on corrosion rate of alloys with different initial microstructures at a consistent concentration were analyzed. Compared to the alloy with initial lamellar microstructure of 3054 kJ/mol, the alloy with initial equiaxed microstructure had an activation energy of 4155 kJ/mol. As the temperature rises, the rate of corrosion tends to increase. The results suggested that the alloy with initial equiaxed microstructure presented the superior corrosion resistance than the alloy with the initial lamellar microstructure. Additionally, the corrosion morphologies after polarization of the alloy were characterized. And the results show that the surfaces of titanium alloys with initial lamellar microstructure display a comparatively greater incidence of pitting corrosion upon assessment of the corrosion morphology.

A novel Co9S8–MoS2 nanosheet arrays@HCSs with superior capacitive and cycling performance for hybrid supercapacitor

Due to high conductivity and electrochemical activity, transition metal sulfides and their complexes have emerged as attractive electrode materials for supercapacitors. Herein, heterostructures of Co9S8–MoS2 nanosheet arrays on the hollow carbon spheres (HCSs) with yolk-shell structure (Co9S8–MoS2 NSAs@HCSs) are synthesized by a hydrothermal method and in-situ sulfurization of silicates. This core-shell structure can effectively improve the conductivity and reaction kinetics, resulting in a notable improvement in the cycling and capacity properties. The Co9S8–MoS2 NSA@HCSs electrode has an outstanding cycle stability (96.9 %) after 10, 000 cycles at 10 A g−1 and a high specific capacity of 804C g−1 at 1 A g−1. The effects of solution concentration and sulfurization time on the microstructures and electrochemical properties of the electrode are also investigated. Furthermore, the hybrid supercapacitor (HSC) is assembled with Co9S8–MoS2 NSA@HCSs (positive electrode) and HCSs (negative electrode). Additionally, the HSC delivers 98.2 % of cycling stability after 10, 000 cycles at 10 A g−1. The energy density of 45.6 Wh kg−1 can be obtained at the power density of 770.4 W kg−1.

Intramolecular Singlet Fission Coupled with Intermolecular Triplet Separation as a Strategy to Achieve High Triplet Yields in Fluorene-Based Small Molecules.

In this work, detailed experimental proof and in-depth analysis of the singlet fission (SF) mechanism, operative in fluorene-based small molecules, are carried out by employing advanced time-resolved spectroscopies with nanosecond and femtosecond resolution. The investigation of the effect of solution concentration and solvent viscosity together with temperature and excitation wavelength demonstrates INTRAmolecular formation of the correlated triplet pair followed by INTERmolecular independent triplet separation via a "super-diffusional" triplet-triplet transfer process. This unconventional INTRA- to INTERmolecular SF may be considered an "ideal" mechanism. Indeed, intramolecular formation of the correlated triplet pair is here interestingly proved for small molecules rather than large multichromophoric systems, allowing easy synthesis and processability while maintaining good control over the SF process. On the other hand, the intermolecular triplet separation may be exploited to achieve high triplet quantum yields in these new SF small molecules.

Numerical analysis of MICP treated sand based on bio-chemo-hydro model.

Microbially Induced Calcite Precipitation (MICP) represents an environmentally friendly and innovative soil grouting technology. Involving intricate biochemical processes, it poses challenges for a thorough investigation of factors influencing microbial grouting effectiveness through experimentation alone. Consequently, A three-dimensional numerical model was developed to predict the permeability of bio-grouting in porous media. The numerical model is validated by comparing its results with test results available in the literature. The validated model is then used to investigate the effects of variation bacterial solution concentration, cementation solution concentration, grouting rate and grouting time on grouting effectiveness. It was founded that the remediation effect was positively correlated with the bacterial solution concentration and the number of grouting. An increased grouting rate enhanced the transport efficiency of reactants. Additionally, the concentration of cementation solution exhibited no significant effect on the reduction of calcium carbonate yield and permeability.

Application of a new chitosan derivative for adsorption of copper (II) and oxyanions of chromium (VI)

This study describes the synthesis of a new bioadsorbent from chitosan using ethylenediaminetetraacetic dianhydride (EDTAD) as a modifying agent and its successful application for removal of a cationic ion (copper (II) (Cu2+)) and oxyanions of chromium (VI) (Cr6+) from single-component aqueous systems. The new multifunctionalised chitosan derivative (C1) was produced through chemical modification of the primary hydroxyl function of chitosan with EDTAD to introduce carboxylic and tertiary amine functional groups, maintaining the secondary amines on the chitosan surface. Such a transformation was important not only to increase the adsorptive potential of chitosan but also to allow C1 to be used in acidic media, thus solving the problem of solubility of most chitosan derivatives. C1 was characterised by spectroscopic methods. The effects of solution pH, contact time and initial solute concentration on the removal of copper (II) and chromium (VI) by C1 were investigated in aqueous solutions. C1 showed an experimental maximum adsorption capacity of 106 mg/g for copper (II) and 194 mg/g for chromium (VI).

Synthesis of AuPt Bimetal and its Catalytic Properties in Ethanol Electrooxidation Reaction

AuPt Bimetal has been successfully synthesized by electrodeposition method with potentiostat technique. By varying the concentration of Au ions in the solution they are able to control the morphology and composition of the synthesized sample. The morphology obtained from the AuPt synthesis is cauliflower. The effect of Au ion concentration in solution on the catalytic performance of AuPt, the greater the Au concentration, the greater the current density in the electrooxidation reaction. In addition, the concentration of Au ions in the solution affects the results of the deposition of Au and Pt elements. In the study of AuPt nanocatalysts with a 0.4 mM Au ion concentration in an electrolyte solution, it was shown to have good catalytic activity in the ethanol electrooxidation reaction, with the resulting current densities and If/Ib of 10.1 mA/cm2 and 43.53 mA/cm2, respectively. This is an implication of many Au compositions which are known to have the ability to absorb and oxidize CO to encourage an increase in current density and increase its catalytic activity.

Preparation of Hirudin-Loaded Chitosan/Polycaprolactone Bowl-Shaped Particles and an Application for a Drug Delivery System

Atherosclerosis, a disease that mainly affects human blood vessels, can cause various cerebral ischaemic diseases such as coronary heart disease and peripheral arterial disease. However, conventional drugs for the treatment of atherosclerosis have the disadvantages of low bioavailability and high toxicity. Bowl-shaped particles not only have the excellent properties of traditional spherical particles, such as improved drug distribution, increased drug absorption, reduced drug toxicity and side effects, but also are easier to circulate in the blood for a long time, have reduced immune rejection and have a larger specific surface area. Chitosan/polycaprolactone bowl-shaped particles were prepared via electrostatic spraying, and the effects of precursor solution concentration and polymer ratio on particle morphology were investigated. Chitosan/polycaprolactone composite bowl-shaped particles containing hirudin were prepared under optimal parameters for sustained anticoagulation. The anticoagulant molecules of hirudin could be continuously released from the composite scaffold as the bowl particles degraded. The biocompatibility and haemocompatibility of the composite particles were assessed using mouse glial cells and rabbit blood, and the results showed that the cell viability of the drug-loaded particles was overall above 90% and the haemolysis rate was below 2%. By controlling the release rate of hirudin, bowl-shaped particles can achieve a long-term anticoagulant drug delivery system and have wider application potential as a novel blood contact material.

Effect of Solution Concentration and Anodizing Coating Time on Hardness and Thickness Coating Of 7075-O Aluminum Alloy

One of the materials used in ship propellers is aluminum alloy. The advantages of aluminum are that it is easy to cast and relatively resistant to corrosion. This research aims to determine the effect of heat treatment and the effect of variations in the concentration of H2SO4 and immersion time in optimal of the anodizing process on the hardness value of 7075-O aluminum alloy (as-cast aluminum alloy). The method used is solution heat treatment at a temperature of 490ºC with a holding time of 6 hours, quenching using water or oil, with artificial aging at a temperature of 120ºC with a holding time of 24 hours. In the anodizing process, a sulfuric acid solution with various concentrations of 10%, 15%, and 20% with variations in immersion time of 10, 15, and 20 minutes. The results of vickers hardness test on heat-treated specimens with water quenching accompanied by artificial aging is 137.54 HV, it is increased by 47.44%. While the results of the vickers hardness test after anodizing is 213.09 HV, it is increased by 128.42%. Where the optimum hardness value was achieved at a concentration of 15% H2SO4 and an immersion time of 20 minutes. The coating thickness is equal to 25.79 µm.

The effects of Escaig stress and solution concentration on the interaction between screw dislocation and coherent twin boundary in random alloys

The effect of Escaig stress as well as the solution concentration on the interaction between screw dislocation and coherent twin boundary (CTB) in random Ni–Co alloys is investigated using molecular dynamics (MD) simulations. Our results show that Co concentration would promote the screw dislocation-CTB reaction from absorption to transmission. And Escaig stress can influence the critical interaction shear stress (CISS) depending on its magnitude and direction, even changing the mode from transmission to absorption, which is not recognized before. Such phenomenon is well interpreted by modifying the traditional criterion through considering the differences between the average stacking fault energy (SFE) and elastic repulsion within the dislocation, which suggests that the repulsion under specific Escaig stress can better assess the reaction mechanism. Our results provide new insights in understanding the high-strength properties of nanotwinned face-centered cubic (FCC) metals or alloys.

Unveiling the potential of forward osmosis desalination: Multi-objective optimization for peak efficiency

Forward osmosis (FO) has emerged as a promising technology with diverse applications. While recent advancements in FO have primarily focused on developing efficient membranes and draw solutes, studies on process optimization remain scarce. This work aims at identifying optimal operating conditions to use FO in seawater and brackish water desalination. Central Composite Design was conducted to investigate the effects of draw solution concentration, temperature, and flow rate on water flux (Jw), reverse solute flux (RSF), and specific cost index (Isc) responses. Response Surface Methodology analysis was performed to identify factors influencing responses. The desirability function was used to determine the best-input variables. The optimum operating conditions for the FO process are found at a flow rate of 0.6 L/min, a temperature of 32.9 °C, and a concentration of 1.79 mol/l, with corresponding values for water flux, RSF and Isc of 18.16 L/m2h and 41.03 g/m2h and 0.274, respectively. These results were experimentally validated. Experiments were also performed using seawater and brackish water feed solutions.

INVESTIGATION OF THE IMPACT OF DIFFERENT PARAMETERS ON THE MORPHOLOGY OF ELECTROSPUN POLYURETHANE NANOFIBERS

In this research, nonwoven nanofiber mats were prepared using the electrospinning method for the solution of polyurethane polymer dissolved in acetic acid. Effects of solution concentration, solution flow rate, as well as high voltage on the morphonology and wettability of the prepared nanofibers were studied. Nanofiber morphology was investigated through the analysis of scanning electron microscopy (SEM) micrographs using ImageJ software, while the wettability of the nanofiber mat surfaces was studied through the measurement of the contact angle. Results revealed that when the concentration of the solution was changed from 8wt% to 12wt%, the average nanofiber diameter showed a significant increase from 0.326 µm to 0.380 µm, while the contact angle increased from 39 degrees to 79 degrees. Results also showed that when the applied high voltage was changed from 10 KV to 25 KV, the average nanofiber diameter decreased and then increased within the range of 0.380 to 0.497 µm and that the contact angle was increased from 81 degrees to 108 degrees showing an obvious switching from hydrophilic towards hydrophobic surface. When the syringe pump flow rate was changed from 0.012 ml/min to 0.02 ml/min, morphology measurements showed that the average nanofiber diameter showed a significant increase from 0.351 µm to 0.456 µm, and the surface contact angle was also increased from 43 degrees to 98 degrees. Finally, the results of Fourier Transform Infrared Spectroscopy (FTIR) and X-ray diffraction analysis (XRD) tests showed that the electrospun polyurethane polymer material used in this work was not changed during the electrospinning process.

A mass transfer study of CO2 absorption in aqueous solutions of isomeric forms of sodium alaninate for direct air capture application

Direct air capture (DAC) of CO2 is a critical emerging technology required to achieve ambitious net-zero emissions. Aqueous amino acid absorbents are ideal candidates for DAC and this work describes the investigation of the CO2 absorption performance of sodium salts of β- and α-alaninate under relevant conditions for DAC by utilising synthetic CO2 gas streams at concentrations levels found in the atmosphere (200–600 ppm). The effects of solution concentration, temperature, gas flowrate, liquid flowrate, and dissolved CO2 concentration (i.e., CO2 loading) on CO2 mass transfer coefficients were investigated. The overall mass transfer coefficient was found to be independent of the gas and liquid flowrates, with larger values determined for β-alaninate solutions (0.75–1.16 mmol m−2 s−1 kPa−1) than that of α-alaninate (0.65–0.87 mmol m−2 s−1 kPa−1), under similar experimental conditions. The results showed that the overall mass transfer coefficient increases with increasing temperature, conversely decreasing steadily with increasing CO2 loading. The maximum CO2 loading capacity of the 5.0 M solutions was ∼10 % higher for β-alanine (0.651 mol CO2/mol alaninate) than α-alanine (0.607 mol CO2/mol alaninate) at 25.0 °C. Precipitation was found to play an important role in the CO2 absorption processes here. Interestingly, beyond CO2 loadings >0.12 mol CO2/mol α-alaninate, the 5.0 M solution of α-alaninate begins to develop precipitate(s) while precipitation in the β-alaninate solution is only initiated at much higher CO2 loadings >0.52 mol CO2/mol β-alaninate. This study provides valuable insights into the suitability of β-alanine and α-alanine for CO2 capture directly from the ambient air.

Nano-Crystalline Cadmium Oxide Thin Films for Supercapacitor Application: Effect of Solution Concentrations

Nano-Crystalline Cadmium Oxide Thin Films for Supercapacitor Application: Effect of Solution Concentrations

Effect of adrenaline concentration in tumescence solution on intraoperative hemodynamics of liposuction patients: A randomized triple-blind trial

ABSTRACT Background Epinephrine in liposuction solution mediated vasoconstriction thus decrease in adrenergic side effects, local anesthetic toxicity, and bleeding. The optimum safe adrenaline concentration was not well investigated. Aim This study aimed to compare between adrenaline 1 mg/L and 2 mg/L in tumescent fluid concerning hemodynamics during abdominal liposuction operations. Methods Forty cases scheduled for liposuction for abdomen and flanks and body were involved in this randomized, triple-blind, controlled trial. Cases were randomized equally into two groups. Group A (low adrenaline concentration group): received 1 mg per liter of epinephrine. Group B (high adrenaline concentration group): received 2 mg per liter of epinephrine. Results Intraoperative heart rate and mean arterial blood pressure at base line were insignificantly different between both groups (p value > 0.05) while at 30, 60, 90, and end of surgery were significantly higher in group B group as opposed to group A (p value < 0.05). Incidence of sinus tachycardia and PVCs were significantly higher in group B than group A (P < 0.05), while surgeon satisfaction was comparable between both groups (p value > 0.05). Conclusions In liposuction procedures, the safest adrenaline concentration is 1 mg/L as evidenced by hemodynamics stability and surgeon satisfaction thus even in high volume liposuction, the adrenaline concentration should not exceed 1 mg/L and should be handled to cover the used crystalloid solution.

Lightweight, robust, porous heterocyclic para‐aramid aerogel hollow fibers for multifunctional applications

AbstractIn nature, many fibers with warmth‐retention properties, such as the hair of polar bears and rabbits, both have a hollow cross‐section structure. The static air in fiber cavities can effectively inhibit heat conduction and serve as an effective thermal insulator. In this work, the high‐performance heterocyclic para‐aramid polymer was selected as the spinning solution, and aerogel hollow fiber was prepared by coaxial wet spinning and freeze‐drying techniques. The effects of spinning solution concentration and lyophilized solvent on the micromorphology, mechanical properties, and specific surface area of heterocyclic para‐aramid aerogel hollow fiber (HPAAHF) were systematically studied. The produced HPAAHF possessed excellent mechanical properties (tensible strength ~3.85 MPa), high specific surface area (~ 260.90 m2 g−1), and lightweight advantages. The thermal conductivity of HPAAHF was only 0.0278 W m−1 K−1, indicating its excellent thermal insulation properties. The aerogel fabric exhibited outstanding flame retardancy properties, with a total heat release of only 0.7 MJ m−2 in the cone calorimetric experiment, making it a self‐extinguishing fabric. In addition, phase change material was injected into the hollow structure to obtain aerogel‐phase change material composite fibers, which exhibited great energy storage prospects. As a result, the high‐performance heterocyclic para‐aramid polymer‐based aerogel hollow fiber was successfully prepared and had multifunctional applications in thermal insulation, flame retardancy, and heat energy storage fields.

Optimization of the Centrifugal Spinning Parameters to Prepare Poly(butylene succinate) Nanofibers Mats for Aerosol Filter Applications.

Air pollution is becoming a serious issue because it negatively impacts the quality of life. One of the first most useful self-defense approaches against air pollution are face masks. Typically made of non-renewable petroleum-based polymers, these masks are harmful to the environment, and they are mostly disposable. Poly(butylene succinate) (PBS) is regarded as one of the most promising materials because of its exceptional processability and regulated biodegradability in a range of applications. In this regard, nanofiber-based face masks are becoming more and more popular because of their small pores, light weight, and excellent filtration capabilities. Centrifugal spinning (CS) provides an alternative method for producing nanofibers from various materials at high speeds and low costs. This current study aimed to investigate the effect of processing parameters on the resultant PBS fiber morphology. Following that, the usability of PBS nonwoven as a filter media was investigated. The effects of solution concentration, rotating speed, and needle size have been examined using a three-factorial Box-Behnken experimental design. The results revealed that PBS concentration had a substantial influence on fiber diameter, with a minimum fiber diameter of 172 nm attained under optimum production conditions compared to the anticipated values of 166 nm. It has been demonstrated that the desired function and the Box-Behnken design are useful instruments for predicting the process parameters involved in the production of PBS nanofibers. PBS filters can achieve an excellent efficiency of more than 98% with a pressure drop of 238 Pa at a flow rate of 85 L/min. The disposable PBS filter media was able to return to nature after use via hydrolysis processes. The speed and cost-effectiveness of the CS process, as well as the environmentally benign characteristics of the PBS polymer, may all contribute considerably to the development of new-age filters.