Enhancement of Antibacterial and Mechanical Features of Glass Ionomer Restoration by Adding ZnO Nanoparticles Prepared by PLAL: In Vitro Study

The objective of this manuscript was to study the antibacterial and mechanical effect on composition ZnONPs-Glass Ionomer restoration. Zinc oxide nanoparticles prepared by laser ablation in liquid at different concentrations. After that, the glass ionomer was adding in calculated amount to get homogenous composition. The physical properties of resulted NPs were examined by FTIR, XRD, TEM, and AFM. The Antibacterial activity against streptococcus mutant and compressive strength were also measured. The result of the FTIR spectrum confirms the formation of the Zn-O bond. XRD pattern shows peaks at 28..55°, 31.21° and 42.70°, correspond to the (100) (101) and (102) crystal planes of cubic Zinc Oxide structure. TEM image exhibits spherical and homogenous ZnO nanoparticles with particle size <50nm. Also, the result shows a significant increase in the antibacterial property of ZnO-GI with good modifying the mechanical properties. Thus adding ZnO nanoparticles to glass ionomer restoration can be considered as a better alternative to conventional GI.

Determination of Temperature-Dependent Coefficients of Viscosity and Surface Tension of Tamarind Seeds (Tamarindus indica L.) Polymer

The rheological properties of tamarind seed polymer are characterized for its possible commercialization in the food and pharmaceutical industry. Seed polymer was extracted using water as a solvent and ethyl alcohol as a precipitating agent. The temperature’s effect on the rheological behavior of the polymeric solution was studied. In addition to this, the temperature coefficient, viscosity, surface tension, activation energy, Gibbs free energy, Reynolds number, and entropy of fusion were calculated by using the Arrhenius, Gibbs–Helmholtz, Frenkel–Eyring, and Eotvos equations, respectively. The activation energy of the gum was found to be 20.46 ± 1.06 kJ/mol. Changes in entropy and enthalpy were found to be 23.66 ± 0.97 and −0.10 ± 0.01 kJ/mol, respectively. The calculated amount of entropy of fusion was found to be 0.88 kJ/mol. A considerable decrease in apparent viscosity and surface tension was produced when the temperature was raised. The present study concludes that the tamarind seed polymer solution is less sensitive to temperature change in comparison to Albzia lebbac gum, Ficus glumosa gum and A. marcocarpa gum. This study also concludes that the attainment of the transition state of viscous flow for tamarind seed gum is accompanied by bond breaking. The excellent physicochemical properties of tamarind seed polymers make them promising excipients for future drug formulation and make their application in the food and cosmetics industry possible.

Kinetics of adsorption of methylene blue onto activated kolanut pod

A batch adsorption process was carried out by optimizing, the effect of contact time (10min to 180min) and initial concentration (5mg/l to150mg/l). The adsorbent was characterized using FTIR spectra and SEM, and the result obtained showed shifting and disappearance of peaks after adsorption. The results of the adsorption kinetics, which includes the correlation coefficient 0.9771 and the agreement between the amount adsorbed experimentally (1.472mg/g) and the calculated amount absorbed(1.196mg/g) revealed that MB was adsorbed satisfactory according to the pseudo second-order kinetic model.

Synthesis and research of polyfunctional silicon-containing amines – new promoters of adhesion

Currently, in order to obtain high-tech hybrid products, modern adhesives have high requirements for creating strong joints between dissimilar materials. It is known that adhesion depends on the compatibility of the adhesives with the surfaces of the materials. Amine compounds are the main hardeners for epoxy compositions. That is why, in this article, we synthesized silicon-containing amines based on polyfunctional aminoalkoxysiloxanes for epoxy compositions. Aminoalkoxysiloxanes were prepared by the interaction of 3-aminopropyltriethoxysilane with monoethanolamine in nitrogen at atmospheric pressure in the presence of a binary antioxidant and catalytic amounts of an alkali metal alcoholate. During the reaction in a homogeneous phase, the reaction mixture was heated to a temperature of 100-110 °C and distilled off to 90% of ethanol from the theoretically calculated amount. Further, the reaction was carried out at a reduced temperature of 10-20 mmHg pressure until the release of alcohol stops. At the same time, gravimetric control was carried out and the refractive index of the reaction mixture was measured. As a result, aminoalkoxysilanes were obtained in the form of light-yellow oily liquids. The structure of the obtained compounds was investigated by IR spectroscopy on an FSM-1202 Fourier spectrophotometer and 1H NMR spectroscopy on a high-resolution BrukerWM-250 NMR spectrometer. It was found that under the selected synthesis conditions, aminopropyltri-(2-aminoethoxy)silane is obtained with the highest yield of 97.6% at a molar ratio of 3-aminopropyltriethoxysilane AGM-9 with monoethanolamine 1:3.

Geoinformation Modeling of Determination a Soil Pollution by Lead Compounds in Highway Agroecosystems

This work examines the method of geoinformation modeling in determining the degree of soil pollution by Pb compounds in the highway ecosystems, used as agricultural areas. The methodology allows identifying the spatial parameters of the area of pollution and the territories safe for cultivating crops by determining the actual level of soil contamination. The actual level of pollution (ALP) reflects the estimated balance of Pb compounds in soils over a specified period of time and the duration of pollution (or decontamination) period under the conditions of existing anthropogenic pressure. ALP is defined as the difference between the calculated amount of Pb compounds that have been introduced into the soils of the geosystems from the main sources of emissions and their calculated amount that has been lost from the soil and/or removed from migratory flows (by being transferred to the state conditionally inaccessible by plants), for the same time interval. Methodology verification took place in the geographic area representative of forest-steppe zone of Ukraine by its environmental conditions and agricultural use. Methodology implementation was conducted by building spatial regional databases, utilizing the data from field and laboratory soils studies and open sources of digital spatial data. Based on geoinformation modeling, we determined the configuration and quantitative characteristics of the primary zone of contamination of the soil surface layer with Pb compounds. We presented the calculation procedure of quantitative indicators of soil decontamination from Pb compounds as they redistribute through the soil profile via main geochemical scenarios. We also provided the rate of this process under the conditions of the existing anthropogenic pressure. Using modeling results, we mapped areas of removal, transit and accumulation of Pb compounds and territories receiving pollution from highway geosystems. Verification of the modeling results during laboratory studies proved the objectivity of the proposed methodology in determining the current levels of pollution with Pb compounds. Our methodology could be utilized for a set of different environmental factors as well as other heavy metals with a purpose of identifying areas safe for cultivating crops.

Change in the direction of the polarization vector and redshift of an incoming light ray as observed from a rotating frame

In the present work, the change in the direction of the polarization vector of an incoming light ray is extensively calculated for a rotating observer. The change in the direction of the polarization vector calculated here is only due to the effect of the non-inertial rotating frame, considering that the light source is at a distance and it is emitting plane-polarized light. The metric tensors for a rotating observer have been collected from existing literature. Accordingly, the electric displacement and magnetic induction values as applicable for a rotating observer have been calculated. These values are used to calculate the change in the orientation of the electric vector of an incoming plane-polarized light ray. Earth has been taken as an example of a rotating frame and the calculated amount of change in the direction of the polarization vector has been found to be dependent on the azimuthal and polar coordinates of the rotating frame. The present work also discusses the redshift as observed by a rotating observer and the value of the redshift has been calculated for an observer sitting on a rotating earth.

Smart Parking Management System using IoT

Today’s world is of Technology, technology is a kind of boon to enabling human lives comfortable as well as swift. The utilization of sensible phones has enormous applications. The IoT(Internet of Things) platform enables to attach physical modules with the net. In consequence, several applications can be carried out. This paper represents proposed system of one of them. There are parking problems in big urban and crowded cities because of unplanned parking, which becomes problem to find parking yards, more time-consuming to park a vehicle. Although ample quantity of analysis works on the event of good parking system exist in literature, but most of them have not addressed the problem of real-time detection of parking lot and automatically generation of hourly basis parking charges. This paper addresses proposed system to solve the problems and bring out better performance by using IOT, GPS (Global Positioning System) to locate nearest parking yard to reduce time consuming, camera for detection of the vehicle number in order to allow vehicle into parking lot, and mobile application to find vacant lot and for advance booking. Moreover, this system avails online payment link for parking charge for calculated amount of parked hours, sends notifications. These all interface with Raspberry pi. Eventually, this system reduces time-consuming and makes easy parking

Studi Mengenai Pengaruh Gradasi Agregat Kasar terhadap Kebutuhan Air untuk Mencapai Suatu Kelecakan Campuran Beton pada Cara SNI. (Hal. 73-82)

ABSTRAKKebutuhan air untuk mencapai suatu rentang kelecakan campuran beton yang direncanakan pada cara SNI hanya bergantung pada ukuran maksimun agregat kasar dan jenis agregat yang digunakan. Pada cara SNI ini banyaknya ragam gradasi agregat kasar yang digunakan selama ukuran maksimumnya tidak berubah, maka jumlah air yang dibutuhkan tetap sama. Kejelasan tentang jenis gradasi agregat kasar yang terdapat pada perkiraan jumlah air dalam campuran beton sangat perlu untuk memperhitungkan kebutuhan air campuran beton menjadi lebih tepat. Penelitian ini dilakukan untuk mengetahui pengaruh gradasi agregat kasar terhadap kebutuhan air campuran beton pada cara SNI. Kebutuhan air campuran beton berbanding lurus dengan persentase jumlah air tiap ukuran agregat kasar yang digunakan. Hasil penelitian menunjukan bahwa jumlah air yang dibutuhkan sesuai dengan perhitungan jumlah air yang dihitung. Jumlah air yang dibutuhkan dapat dirumuskan sebagai jumlah dari persen ukuran agregat kasar dikali jumlah air dari tiap ukuran agregat kasar tersebut.Kata kunci: cara SNI, gradasi agregat kasar, kebutuhan air. ABSTRACTAmount of waters that need to reach a slump range of mix concrete that planned on SNI only depending on maximum amount of coarse aggregate and the kind of aggregate. Depending of SNI, variety of graded coarse aggregate as long as the maximum amount does not change or stable does not change the amount of water needed. Clarity of the kind of coarse aggregate graded on water amount estimate to calculate a water on mix concrete to be accurate. The study was done to overcome the effect coarse aggregate graded to amount of water needed on SNI. The water needed mix concrete directly proportional with percentage of water every size of coarse aggregate used. The result shown that amount of water needed equivalent with calculation of water that calculated. Amount of water needed can be formulated as a total of percentage size of coarse aggregate multiplied by amount of water of every size of coarse aggregate.Keywords: SNI method, coarse aggregate graded, water needed.

Characteristics of commercial-scale radio-frequency/ vacuum (RF/V) drying for hardwood lumber

Two runs of commercial-scale radio-frequency/vacuum (RF/V) drying for maple hardwood were performed to explore the practical technology and its drying characteristics. The results revealed that the power density was a prerequisite for the drying schedule development. The drying time and in-process moisture content (MC) were evaluated by the calculated amount of dehydration at 1% MC removal. The drying defects, such as checks, bowing, and twist, and MC variation met the requirements of GB/T 6491 (2012). The drying rate of run 2 increased 22% after the drying schedule modification. The dehydration capacity was affected by the temperature, which first increased fast as the wood temperature increased to the boiling point and then increased more slowly after that point. The dehydration capacity was also associated with the initial lumber MC. Approximately 30% of the total energy maintained the chamber vacuum and approximately 70% was used for RF heating for both runs. The overall specific energy for water removal during RF/V drying had a competitive advantage compared with conventional kiln drying. The energy conversion efficiency of both runs was low at 50% during the warming stage, and increased to 80% and 90% for Run 1 and Run 2, respectively, during the drying stage.

Study of the effect of stepped dosing of sulfuric acid in the process of decomposition of apatitis

An experimental study of the effect of stepwise dosing of sulfuric acid in the process of decomposition of apatite with sulfuric acid has been performed. The process of decomposition of apatite in the apatite-H3PO4-H2SO4-H2O system was carried out with stepwise dosing of sulfuric acid. At the beginning of the process, the calculated amount of phosphoric acid and half of the stoichiometric amount of sulfuric acid required for the decomposition of the loaded amount of apatite was loaded into the batch reactor. It was experimentally shown that the pH of the reaction mixture at the beginning of the process increases to a pH value of 6.13, at the same time there is a decrease in the concentration of sulfuric acid and the formation of phosphoric acid, this is due to the decomposition of apatite in the reaction mixture. Already in the seventh minute, the concentration of sulfuric acid is zero, and the concentration of phosphoric acid has the first peak value, after which it begins to decrease. Thus, at the beginning of the process, the formation of phosphoric acid occurs due to the decomposition of apatite with sulfuric acid. Since sulfuric acid was added at the beginning of the process with a deficiency (0.5 mol) of sulfuric acid is not enough to decompose the charged apatite, a decrease in the concentration of phosphoric acid and the formation of monocalcium phosphate are observed after the peak. This is due to the consumption of phosphoric acid on the decomposition of the remaining apatite with the formation of monocalcium phosphate. At the 140th minute, the remaining stoichiometric amount of sulfuric acid was added to the reactor (0.5 mol), a sharp drop in pH to 5.48 and a simultaneous increase in the concentration of phosphoric acid were observed. Consequently, sulfuric acid is consumed for the decomposition of monocalcium phosphate. Thus, it was shown that with an insufficient amount of sulfuric acid, the resulting phosphoric acid is spent on the decomposition of apatite with the formation of monocalcium phosphate. Adding sulfuric acid makes it possible to extract production phosphoric acid from monocalcium phosphate.