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The purpose of this study was as a feasibility study of the utilization of oleamide as a new additive for natural rubber (NR) filled with silica using the semi-efficient vulcanization system. Silica fillers used as much as 30 parts per hundred parts rubber (phr). Oleamide was obtained from the synthesis of oleic acid with urea. Oleamide was inserted into the silica filled NR compounds with the varied composition of 0.0 phr; 2.0 phr; 4.0 phr; 6.0 phr, and 8.0 phr. The influence of oleamide on the curing characteristic of the silica filled NR compounds was observed. It was obtained that the oleamide functions as a curative and also a plasticizer. The greater the levels of oleamide added, the shorter the scorch time and optimum curing time were. Oleamide also decreased the minimum torque with addition up to 8.0 phr. The greater the levels of oleamide was, the lower the minimum torque was. Oleamide also increased the maximum torque and torque difference of the silica-filled NR composites at the addition of 2.0 phr. The 2.0 phr was the optimum composition of the oleamide.

Mambong pottery in Kuala Krai, Kelantan is one of the types of potteries in Malaysia other than Sayong, Terenang and Sarawak pottery. Mambong pottery was being made by traditional technique like pinching and throwing. In this research, Mambong pottery was made by using slip casting method. This method used porous mould which can absorb the water content from the clay slip. Different composition of water and clay was used and its effect on product properties was investigated. Samples with different composition of water and clay were labelled as 50C50W, 60C40W, 70C30W and 80C20W samples with addition of 0.7% of sodium silicate, Na2SiO3. The samples were characterized by its specific gravity (S.G.) of clay slip, drying and firing linear shrinkage, density and porosity and strength of the clay samples. Finding from this research showed that 70C30W sample is the optimum composition in fabricating pottery by using slip casting among other samples.

In this work several CuO–ZnO/Al2O3 co-impregnated catalysts were tested for methanol steam reforming (MSR) in order to statistically optimize the Cu and Zn content. All catalysts showed initial deactivation, due to Cu sintering, which was detected by the BET area and transmission and scanning electronic microscopy analyses, performed before and after the reactions. The products obtained in the reactions were only H2 and CO2, and the formation of CO or coke was not verified. It was possible to adjust a second order equation to the methanol conversion (after 3 h in reaction) as a function of the Cu and Zn content, using the RStudio free program. The optimum composition obtained by the surface response methodology (RSM) was 20.7% Cu and 13.4% Zn, and the catalyst synthesized with this content (19.4% Cu–15.5% Zn) had the highest Cu area and dispersion and thus presented the highest methanol conversion, corroborating the statistical analysis.

Asbuton is a natural asphalt from mountains/rocks on Buton Island, Indonesia, with deposits of 677.247 million tons with an estimated bitumen content ranging from 15% to 35% or equivalent to 170 million tons of asphalt. The use of granular asbuton in an asphalt mixture requires modifier/rejuvenating material with low viscosity so that it can enter the asbuton granules more easily and can soften the asbuton bitumen and mobilize it evenly in the asphalt mixture. Coconut shell biobinder (BioCS) is a bio-oil fraction produced from fast pyrolysis of coconut shell, with the ability as a modifier/rejuvenator. The use of BioCS for granular asbuton on asphalt mixtures can be an alternative environmentally friendly road pavement technology. Before conducting tests on the asphalt mixture, it is necessary to test the characteristics of the asphalt binder, which is bioasbuton®, which is a binder from BioCS with asbuton bitumen at an optimum composition that can be used as an alternative binder for asphalt mixture. The tests include a chemical structure test using fourier-transform infrared spectroscopy (FTIR), a morphological and elemental content test with scanning electron microscope (SEM) and energy dispersive x-ray (EDX) analysis, a basic physical properties test with a basic rheological test, and a mechanistic physical properties test through dynamic shear rheometer (DSR) temperature sweep. As an asphalt binder base, the asphalt pen 60/70 was used which was then compared with bioasbuton® and asbuton bitumen. The test results show that the characteristics of bioasbuton® are better than asbuton bitumen and meet the specifications of pen 60/70. Based on the results of this study, prove that bioasbuton® as an alternative asphalt binder that has good potential, especially at high temperature performance.

Taguchi method is applied to optimize the compositions of Al-Mg-Ti-Cu-SiC hybrid composites for maximum wear resistance. Wear tests are performed on a pin-on-disc machine under a constant load of 3 kg on specimens of above composites prepared using Taguchi L9 orthogonal array through stir casting route. Each test is conducted for 30 minutes at disc rotational speed of 600 rpm. The contribution of each constituent is evaluated using ANOVA. Linear and quadratic regression models are also developed. The predicted results by these models are very close to the experimental results. It is found that Taguchi method is very successful in the optimization of particulate reinforcements (Mg, Ti, Cu and SiC) in the composites for maximum wear resistance.

This study discussed the applicability of the calcite precipitation method to repair the concrete's crack. The grouting solution of Enzyme-Mediated Calcite Precipitation (EMCP) was modified by adding milk as a catalyst in calcite formation. Cracks in concrete samples were made when the concrete was 28 days with a width of 0.1-0.3 mm. The EMCP solution composed of urease, urea, CaCl2, and milk was injected into the cracked concrete sample, and its effect on permeability and compressive strength tests were evaluated. The result shows that the optimum composition of milk used in the formation of calcite had a concentration of 5 g/L with an initial preparation temperature of 70oC, which produced 26% higher than the initial EMCP solution. The mechanical test results show that the reduction of coefficient of permeability of 92.23% compared to the cracked sample and the improve strength up to 98.75% of the non-cracked sample were obtained by three circles injection. This study elucidated that milk utilization as a catalyst material in repairing cracks with the EMCP method is a potential method for crack-healing concrete.

Combined refractory materials due to their physical and mechanical properties and high stability have been widely used in recent years in metallurgical assemblies with sudden changes in temperature regime, as well as during prolonged downtime or temporary shutdown. Silica refractory can be prepared from clay, chamotte with the addition of silicon production waste (microsilica), as well as with addition of aluminum fluoride production waste (silica gel). In the course of research samples of refractories with different content of modifying additions of technogenic waste in the form of microsilica and silica gel are prepared. The physical and mechanical properties of samples are studied. Examples of using microsilica and silica gel are considered, and based on the results obtained an optimum composition is proposed providing refractory material with high strength and thermal conductivity. Improved properties suggest that microsilica and silica gel may be used as raw materials for the manufacture of combined refractory materials.

With the growing global demands for more sustainable and environmental-friendly construction materials with lesser carbon emissions, some concrete mixtures were modified by incorporating an optimum ratio of effective microorganisms (EMs) and fly ash (FA) and the novel concrete product mixtures were served as an alternative for the ordinary Portland cement (OPC). In this paper, the compressive strength performance, and microstructures of the designed modified concrete materials were evaluated. Four different ratios of EM and FA were selected and evaluated before determining the optimum composition for the conventional OPC. Besides, EMs solution with a ratio of 5, 10, 15, and 20% was added to replace the water content in the OPC. From the study, the addition of EMs and FA components were found to improve the strength and microstructure features of the proposed concretes. Under the presence of FA and 10% EMs, the initial compressive strength (CS) of the proposed concrete was found to be improved by 30%, and the microstructure was observed to be enhanced considerably due to the replacement of OPC with FA and EMs contents. The detailed microstructures analyses (using XRD, EDX, SEM, TGA and DTG) of the FA and EM incorporated concretes displayed the formation of high amount of the Ca(OH)2 and C-S-H gel, reduction in the pores, improvement in the strength performance and enhancement in the structure morphology. From this study, the concrete materials prepared from FA and 10% EM solution can be regarded as an environmental-friendly alternative with fewer contributions toward global warming. As concrete is the main building material used extensively in many construction industries, the present disclosure may alleviate the FA-waste-based landfill requirement considerably.

In civil engineering, alternative materials showed rapid progress. Asphalt derived from Buton Island in Indonesia, also known as Asbuton, was located in the limestone bedrock. A large deposit of Asbuton could guarantee the supply of alternative construction materials. In that regard, Asbuton performance as an alternative material to several subjects needs to be analyzed. Therefore, this study was conducted to analyze Asbuton’s behavior as a filler in a floating column model as a soft soil improvement concept. Asbuton added to sand and gravel mixture as filler and waterglass as a binder. CBR samples were tested to acquire the optimum composition with varied curing days namely 0, 3, and 7 days, following ASTM D-1883, followed by a compressive column model test which was based on ASTM D-2166. Finally, the column applied to the soft soil layer to be tested in a loading test, and the results are then compared for each composition. The results showed that the granular material's composition including Asbuton, the waterglass content, and the curing period significantly affect the engineering properties of the artificial column. The results revealed that the granular column with Asbuton with the addition of waterglass could increase soil’s load capacity and reduce the settlement of soft soils. Doi: 10.28991/cej-2020-03091623 Full Text: PDF

The purpose of this study was to evaluate anti-candidal activity, gelation time, and surface hardness of a short-term soft lining material incorporated with varying concentrations of Piper betle extract (0.25 to 20% w/w). Agar-diffusion assay was conducted to evaluate an inhibitory effect against Candida albicans. The gelation time was assessed and surface hardness was measured at 2 h and 7 days by Shore AO durometer. A soft liner containing at least 5% w/w of P. betle extract was observed the inhibitory effect against C. albicans. An increasing of P. betle concentrations provided larger inhibition zone. Incorporating 5% w/w of P. betle extract into the soft liner did not significantly alter its gelation time and surface hardness (ANOVA; p>0.05). The optimum composition at 5% w/w of P. betle extract can be used as an additive in the soft liner to provide the anti-candidal activity without significantly affect these two main properties.

The discovery and development of drugs that can compete in effectiveness with direct anticoagulants is a critical problem. Fucoidan is a complex branched heteropolysaccharide with anticoagulant and antithrombic activity. Fucoidan drug substance is hygroscopic and possesses poor technological properties. This study was aimed at development of the optimum composition and technology of fucoidan tablets and their biopharmaceutical evaluation. The generalized Harrington desirability function and dispersion and regression analyses were used for optimization of the fucoidan tablet formulation. The contents of crospovidone and lactose were the most significant factors affecting the disintegration and compressibility of model tablets. The lactose content had the greatest impact on the Carr index and Hausner ratio. The in vitro dissolution curves of the tablets were compared (at pH 1.2, 5.7, and 6.8). The in vitro release of fucoidan from the developed tablets obeyed a first-order kinetic equation.

Background/Objectives: The minimization of unnecessary components from agro-waste is essential for performance and conversion into useful products in domestic and industrial utilization. The need for removal of these unwanted components is important to boost the strength of the agro-waste for its effectiveness as additive in agro-based polymer composite production as new engineering material for structural purpose. This investigation entailed the influence of NaOH concentration and soaking time on the key compositional content of novel mango seed shell fiber (MSSF). Methods/findings: The MSSF was treated with NaOH solution at 2.5, 5, 7.5 wt % concentration and soaking time of 2-6 hr. The compositions of MSSF were obtained for the treated and untreated sample by gravimetric method. The pure and NaOH treated MSSF were analyzed instrumentally employing Fourier transform infrared (FTIR) spectrometer to show the functionality of some substances present. From this result, the optimum composition of MSSF was observed at 5 % NaOH concentration and 4 hr soaking time. The maximum composition at this condition improved than the crude MSSF by 71.33% cellulose content, while the hemicelluloses and lignin content removal was lower than the raw fiber by 91.75 and 98.84%, respectively. Application: The results at this optimum treatment of MSSF composition can be recommended for agro-based polymer composite in indoor application. Keywords: Mango seed shell fiber; composition; NaOH; agro-wastes; alkaline treatment

The search and development of drugs that can compete in effectiveness with directly acting anticoagulants is topical. Fucoidan is a complex branched heteropolysaccharide with heparin-like anticoagulant and antithrombotic activities. The fucoidan substance is highly hygroscopic and possesses poor technological properties. This study was aimed at the development of optimum composition and technology of fucoidan-containing tablets and their biopharmaceutical evaluation. The generalized Harrington desirability function and regression and dispersion analyses were used for optimization of fucoidan tablet formulation. The content of crospovidone and lactose were most significant factors affecting disintegration time and compressibility of model tablets. The lactose content had the greatest impact on the Carr index and Housner ratio. The dissolution of tablets was studied in vitro (at pH 1.2, 5.7, and 6.8). The kinetics of fucoidan release from model tablets was described by the first-order kinetics equation.

Some time ago in the region of West Nusa Tenggara (NTB) experienced earthquake shocks which shocked the community so that many buildings were destroyed and razed to the ground. While the current use of plastic waste is a concern of the community and government, especially in the NTB region. So this background is the basis of research to make earthquake-resistant lightweight bricks by utilizing PET plastic waste to replace coarse aggregate as a mixture and use sisal fiber as a reinforcement to strengthen the strength of lightweight bricks. The purpose of this research is to find out how to make light brick type CLC (Cellular Lightweight Concrete) by utilizing PET plastic waste and sisal fiber, to determine the effect of the addition of PET plastic and sisal fiber to the mechanical properties of light bricks, and to determine the optimum composition of the addition of plastic PET and sisal fiber in the manufacture of lightweight brick CLC. The use of PET plastic and sisal fiber produces brick with an average density of 1,830,419 kg / m3 for 1: 1 variation samples, 1,880 kg / m3 for 4: 1 variation samples, and 1,887,654 kg / m3 for 1: variation samples 4. Maximum compressive strength is achieved in 1: 4 variation samples ie samples with the addition of sisal fiber 4 times more than PET plastic. Based on the results of the measurement of the density of bricks, only the sample variation 1: 1 that meets the standards of SNI 2847-2013 light brick (1,140-1,840 kg / m3). The addition of sisal fiber which is 4 times more than PET plastic (sample variation 1: 4) has the highest compressive strength value of 8.5 MPa and is included in the category of lightweight brick quality I.

Methylxanthines such as caffeine, theophylline, theobromine are significant and widespread psychoactive substances. We developed the isocratic method with optimum composition of the mobile phase 90 % water: 10 % acetonitrile and confirmed repeatability of retention times and peak areas. The developed HPLC method was applied to determine the content of methylxanthines in selected types of black and green teas available on the market. Of the black teas (tea bags), the highest concentration of theobromine was found in Ceylon tea (18.98 mg.L−1). The highest concentration of caffeine was in a cup of Earl Gray tea (254.09 mg.L−1). Among loose black teas, the highest content of both theobromine and caffeine was found in Pu Erh Superior tea, where the theobromine content was 24.62 mg.L−1 and the caffeine content was 520.67 mg.L−1. Of green powder teas, highest caffeine content (306.46 mg.L−1) was in Shizuoka Matcha Premium and the highest content of theobromine (8.45 mg.L−1) was found in GABA Midori. From the loose green tea, the highest concentration of theobromine (12.85 mg.L−1) was in Lung Ching West Lake. The highest caffeine content (484.85 mg.L−1) was in Gyokuro Shizuoka Premium Tea. In both types of teas the amount of theobromine and caffeine was quantified, but the presence of theophylline was not proven. Data on contents of these metabolites in tea products are highly informative for consumers.

This work reports the existence of double polarization hysteresis (P–E) loop in Aurivillius-phase ferroelectric Bi4Ti3O12 (BiT) and reveals dramatic influence of small compositional variations on the electrical properties of it. The double polarization hysteresis is a characteristic of the interaction of defects with domain walls. This characteristic becomes more pronounced in Bi-deficient and Mg-doped BiT due to an increase in oxygen vacancy concentration at the lattices. Normal and saturated P–E loop is recalled by Nb donor doping, and associated composition Bi4Ti2.97Nb0.03O12.015 (BiT-0.03Nb) shows high remnant polarization (Pr = 12.5 μC/cm2) and large field-induced strain (S33 = 5.6 × 10−4). In addition, this doping results in bulk conductivity (σb) of BiT decreasing dramatically and associated activity energy (Ea) increasing significantly. In contrast, high oxide ion conductivity is induced with Mg2+ acceptor doping, and at 600 °C the optimum composition has ionic conductivity of ˜0.65 × 10−2 S cm−1 in the bulk.

Energy needs in Indonesia always increase along with population growth and industrial growth. On the other hand, the abundant availability of biomass waste, especially teak sawdust and corn cobs, encouraged researchers to find the right technique for converting biomass waste to make the waste an alternative energy source. Hydrothermal Treatment is one of the techniques for thermal biomass conversion that can convert biomass into coal-like material called hydrochar. The biomass waste is in a heterogeneous or mixed state.The purpose of this study is to obtain the optimum composition of the biomass mixture to make solid fuels using the hydrothermal treatment method and to do a regression analysis to estimate heating value based on proximate analysis. The biomass waste used in this study was teak sawdust and corn cobs powder. The results from this study are the highest yield of hydrochar in the hydrothermal treatment process of teak sawdust which is equal to 68.1% and the highest calor value in the hydrothermal treatment of biomass with the same composition which is equal to 5402 cal / gram. An equation to predict the value calor hydrochar is HHV = 0.837 (% AC) +0.152 (% VM) +0.389 (% FC) -0.022 (% WC) with an absolute error of 4.11% and a relative error of 0.28 %

The quality of railway wheels significantly affects the economy and security of railway transportation. In order to improve the properties of railway wheels steel is used currently with a controlled aluminum content. A feature of this steel is the increased risk of forming large alumina non-metallic inclusions. Nonmetallic inclusions in the defective and defect-free zones of a rejected wheel are studied. The causes of defect formation and a new comprehensive technology of smelting are determined, and ladle treatment and continuous casting of steel are developed, which provide avoidance of forming these defects.The main essence of the technology is the diffusion deoxidation of metal with slag of optimum composition, control of aluminum content during ladle treatment, and use of aluminum exclusively for steel alloying.

Base gas replacement by a cheap gas is one of the approved methods to reduce the cost of investment in underground gas storage process. Maximizing the amount of replaceable base gas is an attractive issue. However, the amount of base gas replacement can be reduced due to some limiting factors. By changing the composition of the candidate base gas, it is possible to obtain a smart gas with an optimized composition through which all limiting factors are simultaneously satisfied. In the present study, the feasibility of this idea is investigated in a real depleted gas reservoir by flue gas as the candidate gas with the aid of GEM compositional simulator and proxy model. The proxy model and Excel Solver optimization tools are used to improve the speed and accuracy in determining the optimum composition of flue gas composition. In addition, the effect of flue gas composition on the reservoir pressure and gas deviation factor is analyzed during gas storage cycles. The results show that when the CO2 content of the flue gas exceeds a specific value, carbon dioxide effect is dominant, which increases the wetting effect of the flue gas. In this case, the simultaneous injection of flue gas and storage gas in odd cycles reduces the reservoir pressure and the reservoir gas deviation factor. The results indicate that it is possible to replace 28.4% of the base gas and reach an enhanced gas recovery of about 18.55% in the reservoir under study using the optimized replacing gas composition of 17.24% CO2 and 82.76% N2.

The results of experimental studies of deformation-strength properties of adhesive joints of a nanocomposite based on AN-111 anaerobic sealant filled with nanoscale particles of copper and aluminum and its optimum composition are described. Comparative data on thermal conductivity and heat resistance of AN-111 sealant and a nanocomposite based on it are presented.

Influence of molybdenum additions on the microstructure and corrosion resistance of powder alloys based on the TaCr2 Laves phase is studied. The phase composition of the alloys in different conditions is determined. Growth in the mass of the alloys is determined after 100-h oxidation at 900°C. The effect of the molybdenum additions on the structure and properties of the TaCr2 -base alloys is shown to be positive. An optimum composition is suggested.

In this research, the wear and mechanical responses of pure magnesium-graphite (Mg–Gr) composite have been investigated aiming to get the optimum composition of reinforcement. The composite materials were fabricated by mechanical alloying. The percentage of graphite reinforcement was chosen as 3, 5, 7 and 10 wt.% to identify its potential for self-lubricating property under dry sliding conditions. The mechanical properties including hardness, tensile strength and flexural strength of the composites and the base material were tested. The wear tests were conducted by using a pin-on-disc tribometer. The results show that the mechanical properties decrease with increasing graphite content as compared to that of the base material. The wear rate and average coefficient of friction decrease with the addition of graphite and was found to be minimum at 5 wt.% graphite reinforcement. The addition of 5 wt.% graphite in the composite exhibits superior wear properties as compared to that of the matrix material and other compositions of the Mg–Gr composites. Keywords: Metal-matrix composites (MMCs), Characterization, Mechanical properties, Wear, Mechanical Alloying

Results are provided for a study of the optimization of a three-component raw material mix for the production of mixed cement. Optimization was performed using the ROCS software package developed by scientists from V. G. Shukhov BSTU and designed for the calculation and optimization of cement production multicomponent raw material mixtures. As a result the optimum composition of raw material mixes is obtained. Cement prepared by mixing 57% of ordinary, 40% of low-base clinker, and 3% gypsum has strength improved by 7,4 and 27,7% with respect to standard cement.

The abrasive wear of reinforced Kh13M2–Cr3C2 steels against a diamond wheel has been studied. The optimum composition of the reinforced chromium steels for the hardening of feed mill hammers has been selected and tested in production conditions. The use of reinforced Kh13M2–Cr3C2 steels to harden the feed mill hammers has been found to be the most effective technique for recovering their original dimensions and performances.

Using reversed-phase HPLC, we developed a procedure for the qualitative and quantitative analytical control of the production of N-octadecyl-1,3-diaminopropane from stearic acid by the nitrile method. The optimum composition of the eluent is determined, which ensures the control of each stage of the process. The calibration dependences for the mixtures initial reagent–reaction product are obtained, suggesting a quantitative estimation of the conversion. The possibility of determining the presence of synthesis by products is shown. The analysis time for each stage does not exceed 20 min.

Development of low-cost, highly efficient and stable CdS-based solid solution photocatalysts is of great significance towards photocatalytic H2 production. Herein, a solvothermal process has been used to fabricate MnxCd1-xS-based products, which can transform into novel heterojunctions consisting of nanorod-like Mn0.2Cd0.8S solid solution and nanoparticle-like α-MnS once the x value is higher than 0.20, and the resulted Mn0.2Cd0.8S/MnS heterojunction containing 38 mol% α-MnS demonstrates an optimum composition ratio with the best H2 production activity (335 μmol h−1), which is 1.95 times higher than that (171 μmol h−1) of the single CdS under visible light (λ ≥ 420 nm) irradiation. After modified with MoS2 cocatalyst via a one-pot solvothermal process, those MoS2-Mn0.2Cd0.8S/MnS composites show significantly improved photocatalytic performance, and the 15 wt% MoS2-Mn0.2Cd0.8S/MnS achieves the best H2 production activity (995 μmol h−1), which is 2.97 times higher than that (335 μmol h−1) of the pristine Mn0.2Cd0.8S/MnS with the optimum composition ratio and also higher than that (868 μmol h−1) of the 1.0 wt% Pt-Mn0.2Cd0.8S/MnS. The well aligned energy band structures and the intimate contacts among Mn0.2Cd0.8S, α-MnS and MoS2 facilitate the photogenerated electron transferring from the nanoparticle-like α-MnS to the nanorod-like Mn0.2Cd0.8S and then to the nanoflake-like MoS2, thus promoting the charge separation and providing more active sites for H2 production reaction. This study not only presents a rare example of binary Mn0.2Cd0.8S/MnS heterojunction photocatalyst consisting of Mn0.2Cd0.8S solid solution and α-MnS, but also paves a new way to explore highly efficient and noble metal-free photocatalytic H2 production system for solar energy conversion.

Active compounds of Cymbopogon winterianius, Cymbopogoncitratus, Rosmarinus officinalis, Cedrus, and Eugenol, have been reported to have different insect repellant compounds. Control and development of natural insect repellent additive based decorative coating has driven this work to incorporate the essential oils with long chain fatty acids in water-based lab developed conventional paint. In this work, the Additive based Paint was formulated and its ability to repel different insects was determined. The optimum composition of developed additive based paint was determined by three standard paint analyses which were adhesion, elasticity and insect repellency. As per challenge of Pigment powder and Polymer use for such paint is achieved by testing on Latest instruments. The best composition of additive in paint was found to be 15%. Where it able to repel Pavement Ants, non-biting Flies, Mosquitoes and Black field ant with 80% efficiency. It is envisioned that the formulated paint is effectively function as insect repellent thus as an alternative way to reduce the insect-borne diseases.

Background: Native breast milk composition displays significant inter- and intra-individual variation which persists after standard fortification with fixed doses and challenges target fortification. This study aims to analyze the macronutrient composition of different commercially available fortifiers and the effect of different fortification strategies on nutritional intake of preterm infants.Methods: In 103 preterm infants, native breast milk samples were collected from 24-h feeding batches (n = 3,338) and fat, protein and carbohydrate contents were analyzed. Nutrient content was compared for breast milk that had undergone either (i) standard fortification, (ii) targeted fortification, (iii) selective batching according to breast milk composition, or (iv) partial lyophilization. For (i) eight commercially available standard fortifiers were tested. Targeted fortification (ii) involved the addition of single component modulars of either protein, fat or carbohydrates to standard fortified breast milk. Using a mathematical growth model, the combined effect of protein, fat and carbohydrate intake on growth was assessed. The best composition of standard fortifiers as the initial step for target fortification was explored assuming three clinical scenarios for milk analysis.Results: Macronutrient content was highly variable between native breast milk samples, and this variation was still present after standard fortification, however at elevated macronutrient levels. Standard fortification, breast milk batching, as well as partial lyophilization of human milk resulted in deficient and imbalanced enteral intakes in a significant proportion of infants. Target fortification reduced this variation in a, respectively, higher percentage of samples. The effect size was dependent on the number of measurements per week. The optimum composition of standard fortifiers was dependent on the clinical scenario (measurement frequency) for target fortification.Conclusions: To provide precise and accurate intakes of macronutrients, breast milk should be target fortified. Standard fortified breast milk can result in excess above recommended intakes of some macronutrients which limits the efficiency of target fortification. Standard fortifiers with improved composition are needed for target fortification.

Conductivity detectors constitute a universal detection technique that is suitable for the determination of non-UV/Vis absorbing compounds, such as carbohydrates. This chapter summarizes the theoretical foundations of conductivity detection and describes the design of contactless conductivity cells for capillary electrophoresis, microchip electrophoresis, and liquid chromatography, with emphasis on the advantages and disadvantages of the individual types and their current commercial availability. Emphasis is placed on the optimum composition of the background electrolyte and mobile phase, which together with the pretreatment of the sample affect the sensitivity of the determination. Special emphasis is placed on the applications of contactless conductivity detection in combination with high-performance separation techniques for determining carbohydrates and their derivatives in food, beverages, and clinical and environmental samples. In the conclusion, a description will be given of the use of contactless conductivity detectors in single-purpose analyzers in connection with automatic sample treatment.

An FeO-SiO2-CaO-Na2O quaternary slag with low melting point was developed for the bath-smelting reduction of Sb2O3. First, the optimum composition of the designed slag was determined through practical experiments to be 36.2% FeO, 31.9% SiO2, 12.0% CaO, and 20.0% Na2O, such that FeO/SiO2 was 1.14. The effects of the main variables influencing the yield and content of antimony in the smelting slag were investigated in detail for the content-optimized slag, and the following optimum smelting conditions were determined: smelting duration of 50 min, rate of coke, i.e., coke dosage of 12.5 wt.%, and smelting temperature of 1000°C. These conditions enabled high recovery of antimony, > 92.0%, and low antimony content in the slag of around 0.97%; the values of both these parameters are superior to those achieved by existing processes.

High-performance cold mix asphalt was prepared based on suitable cold mix asphaltic liquid. First, the contents of raw materials were estimated. The optimum composition of asphaltic liquid was determined by the orthogonal experimental design method. The properties of evaporated residue, adhesiveness, and construction workability were determined. At the same time, the microscopic characteristics of cold mix asphaltic liquid were analyzed by scanning electron microscopy (SEM). The results indicated that Brookfield viscosity was greatly influenced by diluent content at 60 °C. Brookfield viscosity was decreased with the increase of diluent content. Brookfield viscosity was hardly influenced by contents of the additive and styreneic block copolymers (SBS) at 60 °C. Samples 2, 3, 5 and 6 met the requirement of viscosity. The penetration degree of the evaporated residue in asphaltic liquid met the requirement for roads. The Chinese Standard JTG F40-2004 was used to measure the ductility of asphaltic liquids at 5 and 15 °C. The softening points exceeded 50 °C, indicating the excellent high-temperature performance of cold mix asphaltic liquid. The adhesiveness between asphaltic liquid and aggregates was graded at Level 5 (Chinese Standard T0616-1993). The mixture containing samples 5 and 6 was slightly white in color, the fine aggregate was exposed completely. Changing the temperature of the mixture from 90 °C (testing temperature) to 70 °C (mixing temperature), the adhesiveness between aggregate and asphalt was reduced. The fine aggregates were not exposed in the mixture containing samples 2 and 3, and the corresponding mixing ratios can be applied for the production of cold mix asphaltic liquid. Modifiers and additives in cold mix asphaltic liquid were uniformly dispersed. At the same time, it demonstrated that the diluent showed a certain influence on the morphology of residue of cold mix asphaltic liquid, so that a number of folds and holes existed on the surface of the residue.

Waste tire rubber was utilized to get novel PP (polypropylene) composite materials of satisfactory properties to suit various applications. Treatment of waste tire rubber particles was done by H2SO to enhance the adhesion at the interface between the waste tire rubber (WTR) particles and the PP matrix. This affects the properties of the resulting rubber particles composites (RPC). The optimum composition of the composites is selected by studying various WTR particles weight percentages of 5%, 10%, 20%, 30%, 40% and 50% and by using different WTR particle sizes. The physical properties such as water absorption and mechanical properties such as compressive yield strength and hardness were studied for the RPC. The optimum composition of the RPC is selected to suit various applications. Also, dimensional stability of the RPC was determined. Investigations of the WTR particles surfaces were done using FTIR. Keywords: Rubber particles, PP, H2SO4, PP composites, FTIR

The effect of addition of carbon fibers and wollastonite on the mechanical properties of graphite/asphalt/Cu composites is described. The gene expression programming method is used to predict the effects of fillers on their properties. A multiconstraint optimization problem is solved, and the optimum composition is determined.

With the aid of neutron diffraction, the magnetic structure of CaSrFeCoO 6–δ is determined at 10 K and 300 K. The vacancies, created due to oxygen-deficiency, are ordered in this material. In addition to structural order, neutron diffraction shows a long-range G-type antiferromagnetic order, where each magnetic moment is aligned antiparallel to all nearest neighbors. The orientation of moments is along the shortest unit cell axis at 10 K. The magnetic structure and orientation of moments remain unchanged up to room temperature. This is in contrast to the Ca 2 -analogue, Ca 2 FeCoO 6–δ , where the magnetic moments at 10 K are parallel to the longest axis and change their orientation when temperature is raised to room temperature. These differences highlight the ability to control the magnetic properties by tuning the structural parameters. Comparisons to similar materials show that CaSrFeCoO 6–δ has the optimum composition for G-type magnetic order and the retention of the moment orientation.

It is widely acknowledged by all specialists in the field of ferrous metallurgy that the porous peg of the kit for injecting inert gases into the steel casting ladle is the weakness of the entire assembly. This is the most prompted piece due to the thermal shocks that occur when injecting cold gas and the wear and tear and corrosion caused by disturbances in the steel during the injection process. The porous structure of the peg considerably weakens the physical properties and widens the surface of metal - refractory material contact thus enabling the destructive chemical action. In addition, the process of injecting oxygen for cleaning the metal peg also contributes to the destructive action and the substantial decline in its endurance. All these considered, it has been decided that the material for producing these items should contain at least 95% Al2O3 which means using only tabular alumina. As far as the binder is concerned, it has been established that a liquid chemical binder made of colloidal alumina should be used since this does not considerably diminish the Al2O3 content of the end product. It is the aim of this paper to bring forward the author�s research regarding the production of the porous plug using high-alumina refractory materials.

We proposed and examined a material group of methylammonium Pb-Sn mixed halide (MAPb1−xSnxI2.6Br0.4) with various Sn-content (x = 0.2–0.8) for Pb-reduced perovskite solar cells. With suitable Pb-Sn ratio (x = 0.4–0.6), dense coverage of films with better crystallinity was obtained compared with low Sn ratio (x = 0.2). For excess Sn ratio (x = 0.8), poor film-uniformity was found in spite of its enhanced crystallinity. Optimum composition (x = 0.6) provided an impressive power conversion efficiency of 13.4% with remarkable photocurrent output stability, which is related to suppression of trap-assisted recombination regarding the perovskite materials. This promising material paves the way for development of highly efficient, Pb-reduced perovskite photovoltaic cells.

Hydrogen is considered as one of the most important clean and renewable energy sources for a sustainable energy future. However, its efficient and cost-effective purification still remains challenging. In this work, we report the development of novel zeolite@metal–organic framework (MOF) composites comprised of MOF-74 and zeolite-5A with core–shell structure for efficient purification of H2. The composites were synthesized hydrothermally through the addition of zeolite particles with and without carboxyl functional groups to the MOF synthesis solution. The zeolite/MOF weight ratio was varied systematically to find the optimum composition based on the adsorption performance. The formation of zeolite@MOF composites was confirmed by various characterization techniques. Single-component adsorption isotherms of CO2, CO, CH4, N2, and H2 over composites were measured at 25 °C to determine their equilibrium adsorption capacity. It was found that the zeolite-5A@MOF-74 with weight ratio of 5:95 exhibited a similar ...

As the frontier of urban expansion against rural reservations, the urban–rural fringe faces both urban and rural land use problems that result in traffic jams, environmental pollution, and low quality of life. The urban–rural fringe refers to a transitional region characterized by a combination of urban and rural elements. However, the optimum composition of land elements for urban–rural integration remains unknown. Therefore, to effectively express the micro dynamic development of urban–rural fringe areas and guide land use, we formulate essential elements that can be used to enhance urban–rural integration from the perspective of an urban–rural mixed community. This study establishes a theoretical framework to analyze the formation of the urban–rural mixed community and finds that the community is similar to a cell with urban and rural elements. Unlike other studies that consider the entire cell as a grid unit representing a particular land use type, this study aims to investigate intracellular elements based on the general internal structure of a biological cell. Thus, the elements between the urban–rural and biological cells are compared to illustrate the potential optimized path of inner land elements. A comparative case study of the Tangjialing and Erbozi areas in Beijing is conducted to demonstrate the empirical implementation of an urban–rural cell. Our analysis shows that the urban–rural mixed community can be regarded as a micro-unit in achieving urban–rural integration. The inner elements of an urban–rural cell can help provide a suitable concept and design for analyzing the formation and composition of the urban–rural mixed community and propose an applicable way to determine the law for effective land element optimization and urban–rural integration.

An optimum composition and technological regimes of the production of composite wood–coal fuel briquettes from fine brown coal of the Kangalas deposit in the Republic of Sakha (Yakutia) and sawdust without the use of additional binding agents were established.

Molybdenum substitution in the La 2 MgNi 8− x CoMo x alloys can improve the hydrogen desorption properties and affect the electrochemical reaction process for the alloy electrode. The optimum composition of the alloys is La 2 MgNi 7.7 CoMo 0.3 . The discharge capacity ( C max ) and cycle stability ( S 100 ) can reach about 380 mAh/g and 80%, which already exceed the most typical AB 3 -type and commercial AB 5 Co-containing hydrogen storage alloys. The decrease of anti-corrosion ability and the oxidation current density are the main reasons for the performances degradation when the x value is above 0.3 in the La 2 MgNi 8− x CoMo x alloys.

Porous asphalt is a solution to avoid puddles on the road because it has a pore large enough to drain the surface water. However, porous asphalt has low stability, so it is necessary to improve the Marshall stability on a porous asphalt mixture. The purpose of this research is to know the optimum composition of the asphalt content, the coconut fiber content and the coconut fiber length and to determine whether or not there is an effect of adding coconut fiber to the Marshall properties on a porous asphalt mixture. In this study, the treatment used is by making porous asphalt mixture with a variation of the asphalt content of 4%, 5% and 6% and a variation of the coconut fiber content of 0.5%, 0.75% and 1% and a variation of the coconut fiber length of 2.5 mm 5 mm and 7.5 mm to determine the optimum composition of the porous asphalt mixture. The gradation standard used in this study is the Australian Asphalt Gradient Standard and for its specifications using the Marshall characteristics of the Australian Standard (AAPA). Using the response surface method, the optimum value for the asphalt content is 4% and the optimum value of the coconut fiber is 0.75%. The addition of coconut fiber was able to increase the MQ value by 119% from 112.56 kg / mm to 246.64 kg / mm and the stability value 61.56% from 388.32 kg to 627.38 kg. However, the addition of coconut fibers decrease the VIM rate by 18.6% from 20.27% to 18.6% and the flow value by 20% from 3.24 mm to 2.7 mm. These values meet the requirements of porous asphalt’s Marshall characteristics for Australian gradation standard. It is necessary to do a further research using other gradation standard.

Gypsum panels and blocks represent a good economical method for the manufacture of partitions and walls, since the raw material cost as well as the labor cost are cheap, besides the ease of decoration. Their main drawbacks are the high-water permeability and their poor mechanical strength. In the present paper, polypropylene (PP) fibers were blended with plaster in an attempt to improve the properties of these products. It was found that the addition of PP fibers reduces the porosity, decreases the setting time and enhances the mechanical strength. The optimum composition was found to consist of plaster blended with 50% water, 10% sand and 500 g/m3 PP fibers of length 30 – 50 mm.