Effect of extraction ph and temperature on the physicochemical properties and pectin yield from mango peel (Mangifera indica L.)

Objective: To evaluate the effect of the pH and extraction temperature on the pectin yield from mango (Mangifera indica) peel, cultivar Banilejo, and its physicochemical properties. Design/methodology/approach: Pectin extraction was done by acid hydrolysis, using hydrochloric acid and ethyl alcohol to precipitate and purify. A randomized design with a factorial arrangement was used, evaluating the effect of pH (1.5, 2.0, and 2.5) and temperature (70, 80, and 90 ºC) on the yield and quality of pectin. Quality was determined by measuring pH, viscosity and moisture content, ash, methoxyls, and esterification degree. Their means were compared using Tukey's test at 95 % confidence. Results: The best results were obtained at pH 2.0 and 80 ºC, reporting an 18.159 % yield, 6.766 % moisture, 2.630 % ash, 0.085 Pa.s of viscosity, 26.307 % methoxyl, and 64.753 % esterification. Study limitations/implications: The different treatment combinations demonstrate that pH, ash, methoxyl content, and esterification degree vary as a function of the assessed pH and extraction temperatures; while viscosity, moisture and yield were not influenced by these variables. Findings/conclusions: It is concluded that mango peel is a viable source to obtain quality pectin.

Water body measuring pH automated system based on quadcopter

The article discusses monitoring water bodies pH level automated system implementation using an unmanned aerial vehicle (UAV). Floating structure prototype for supporting UAV on water surface is described, taking into account creating a rotor thrust theory. Water hydrogen ions monitoring activity concept using a UAV is presented. Testing results water monitoring system in Lake Boyarskoye (Tomsk, Russia) are presented.

Evaluation of a New Integrated Marine Instruments: RHEA (Drifter GPS Oceanography Coverage Area)

Marine instrumentation is used to make optimal use of natural resources in the marine sector in the form of storing oceanographic characteristics data. This research aims to evaluate a new Lagrangian instrument called RHEA, developed by the Marine Research Laboratory, Padjadjaran University. This research was conducted by examining the correction factors contained in the RHEA from the mechanical and electronic side to optimize the work and carry out appropriate validation of the oceanographic parameter data. The method used is by studying marine instrument literature and conducting a series of tests on the tool until it is ready for use at sea. The output of this research is in the form of literature on how the device works to be effective and efficient in collecting data about certain oceanographic factors. The result shows that RHEA has various functions: measuring pH, dissolved oxygen, temperature, turbidity, and salinity in real-time time. This instrument needs to be slightly modified again related to its design so that it can be more optimal when measuring oceanographic parameter data. In addition, in terms of data acquisition, it is necessary to improve the electronic components by replacing or adding several parts so that the data obtained can have high accuracy.

Indirect assessment of biomass accumulation in a wastewater-based Chlorella vulgaris photobioreactor by pH variation

Algae bloom in coastal waters is partly supported by residual nutrients in treated wastewater (WW) released from coastally located treatment plants. In response, a Chlorella vulgaris-based photobioreactor was recently proposed for lowering nutrient levels in WW prior to release. However, the solution requires maintaining biomass accumulation to within a photobioreactor capacity for optimum operation. For high density Chlorella vulgaris suspensions, this is easily done by monitoring turbidity increase, a property directly related to biomass accumulation. For low density suspensions however, direct turbidity measurement would require a cumbersome process of concentrating large volumes of Chlorella vulgaris suspensions. Here, we demonstrate that by measuring pH of the suspensions, turbidity (T) can be estimated indirectly by the following wastewater-dependent expression: pH = aT + pH0, hence avoiding the need to concentrate large volumes. The term pH0 is the initial pH of the suspensions and a, a wastewater-dependent constant, can be computed independently from a = − 0.0061*pH0 + 0.052. In the event %WW is unknown, the following wastewater-independent Gaussian expression can be used to estimate T: pH = 8.71*exp(− [(T − 250)2]/[2*1.26E05]). These three equations should offer an avenue for monitoring the turbidity of dilute Chlorella vulgaris suspensions in large, stagnant municipal Chlorella vulgaris-based wastewater treatment system via pH measurements.

Thermally Induced Bentonite Alterations in the SKB ABM5 Hot Bentonite Experiment

Pilot sites are currently used to test the performance of bentonite barriers for sealing high-level radioactive waste repositories, but the degree of mineral stability under enhanced thermal conditions remains a topic of debate. This study focuses on the SKB ABM5 experiment, which ran for 5 years (2012 to 2017) and locally reached a maximum temperature of 250 °C. Five bentonites were investigated using XRD with Rietveld refinement, SEM-EDX and by measuring pH, CEC and EC. Samples extracted from bentonite blocks at 0.1, 1, 4 and 7 cm away from the heating pipe showed various stages of alteration related to the horizontal thermal gradient. Bentonites close to the contact with lower CEC values showed smectite alterations in the form of tetrahedral substitution of Si4+ by Al3+ and some octahedral metal substitutions, probably related to ferric/ferrous iron derived from corrosion of the heater during oxidative boiling, with pyrite dissolution and acidity occurring in some bentonite layers. This alteration was furthermore associated with higher amounts of hematite and minor calcite dissolution. However, as none of the bentonites showed any smectite loss and only displayed stronger alterations at the heater–bentonite contact, the sealants are considered to have remained largely intact.

Ammonia Monitoring in Aquarium for Fish Protection and Alert Generation

Fish is an important species that benefits human life in several ways. Fisheries are the best food provider and also aquarium is used at home and public places which becomes decoration cum mind relaxing item. There are lot of attack to fish which goes unnoticed. Large number fish die due to the ammonia (NH3) produced as a by product of protea metabolism and is the most common waste product of fish. There is a given level of ammonia that becomes dangerous and leads to death of the fish. One of the solutions to this issue is to monitor ammonia in aquarium for fish protection and alert generation. A prototype is developed for monitoring the ammonia in the fish tank using Intern is used for protection and alert generation. Ammonia is monitored by measuring pH values. In this project a prototype model is developed that is connected through Internet of Things (IoT) such that it can be monitored in a remote station through mobile app. The prototype model includes an LCD display for local readout. The project will reach the benefit to many engaged in fisheries industry and also who are using Aquarium.

Unified pH Measurements of Ethanol, Methanol, and Acetonitrile, and Their Mixtures with Water

Measurement of pH in aqueous-organic mixtures with different compositions is of high importance in science and technology, but it is, at the same time, challenging both from a conceptual and practical standpoint. A big part of the difficulty comes from the fundamental incomparability of conventional pH values between solvents (spH, solvent-specific scales). The recent introduction of the unified pH (pHabs) concept opens up the possibility of measuring pH, expressed as pHabsH2O, in a way that is comparable between solvent, and, thereby, removing the conceptual problem. However, practical issues remain. This work presents the experience of the authors with measuring pHabsH2O values in mixtures of methanol, ethanol, and acetonitrile, with water, but without the presence of buffers or other additives. The aim was to assigned pHabsH2O values to solvent–water mixtures using differential potentiometry and the ‘pHabs-ladder’ method. Measurements were made of the potential difference between glass electrodes immersed in different solutions, separated by an ionic liquid salt bridge. Data were acquired for a series of solutions of varying solvent content. This work includes experiences related to: a selection of commercial electrodes, purity of starting material, and comparability between laboratories. Ranges of pHabsH2O values for selected compositions of solvent–water mixtures are presented.

Organoleptic Test Formulation of Gel Hand Sanitizer Extract Citronella (Cymbopogon nardus)

Hand sanitizer preparation circulating in the market generally contain alcohol with various concentrations. Continous use of hand sanitizers that contain alcohol will irritate the skin. So that hand sanitizer is needed by using natural ingredients as active ingredients. One of the natural ingredients that can be used is Citronella (Cymbopogon nardus). The purpose of this study was to determine the results of the organoletic test for hand sanitizer gel formulations of citronella (Cymbopogon nardus). This organoleptic test consists of observing odor, color, measuring pH, homogeneity and viscosity. Citronella extract was obtained by distillation method. The results of the organoleptic test in this study were the preparation with a distinctive smell of citronella (Cymbopogon nardus), colorless, and homogeneous hand sanitizer gel preparation was obtained. The pH value of 5 indicates that the hand sanitizer gel preparation is safe touse, because it is still included in the skin’s pH range of 4,5-6,5. Measurement of viscosity using a viscometer tester, the value of viscosity is 100 dPas. ABSTRAK Sediaan hand sanitizer yang beredar dipasaran umumnya mengandung alkohol dengan berbagai konsentrasi. Penggunaan hand sanitizer yang mengandung alkohol secara terus menerus akan menimbulkan iritasi pada kulit. Sehingga dibutuhkan hand sanitizer dengan menggunkan bahan alami sebagai bahan aktif. Salah satu bahan alami yang dapat digunakan adalah sereh wangi (Cymbopogon nardus). Tujuan dari penelitian ini yaitu untuk mengetahui hasil Uji organoleptis formulasi sediaan gel hand sanitizer ekstrak sereh wangi (Cymbopogon nardus). Uji organoleptis ini berupa pengamatan bau, warna, pengukuran pH, homogenitas dan viskositas. Ekstrak sereh wangi diperoleh dengan metode destilasi. Hasil uji organoleptis pada penelitian ini yaitu sediaan berbau khas sereh wangi (Cymbopogon nardus), tidak berwarna, dan diperoleh sediaan gel hand sanitizer yang homogen. Nilai pH 5 yang menunjukkan bahwa sediaan gel hand sanitizer aman digunakan, karena masih termasuk dalam pH kulit yang berkisar 4,5-6,5. Pengukuran viskositas menggunakan alat viscometer tester, nilai viskositas atau kekentalan yang diperoleh yaitu sebesar 100 dPas.

Standardized Procedure of Measuring the pH Value of Cement Matrix Material by Ex-Situ Leaching Method (ESL)

According to the Spanish National Research Council (CSIC) report, the ex-situ leaching method (ESL) is more appropriate and accurate than other methods for measuring pH value in terms of repeatability and reproducibility. In this study, the ESL method was used to measure the pH value of cement matrix materials. The design test process aimed to avoid underestimating the variation in pH during the process of solution stirring and pH measurement without using both argon and nitrogen to block the specimen contact with air, with good repeatability and reproducibility. This study also considered the influence of the dryness of the specimen before crushing, the size of the powder, the air-exposed specimen, the air-exposed solution, the temperature of the solution, etc. After testing and analysis, a standard procedure for detecting the pH value of cement matrix materials was established which is known as the S-ESL method.