Test Solution Research Articles

Controlled Creating of Delaminations in Concrete for Nondestructive Testing

Locating and sizing delaminations is a common inspection task in the maintenance and quality control of construction and rehabilitation. Their detection is an important area of application of nondestructive testing in civil engineering (NDT-CE). To improve this application, NDT test systems and test solutions must be compared, for which specimens containing well-defined delaminations are needed to serve as a reference. Currently, there are no widely accepted procedures available for creating such flaws locally and reproducibly. This study presents procedures for creating artificial delaminations repeatably and as close as possible to natural delaminations. To produce the discontinuities only substances were used which can occur in concrete components and do not affect the application of NDT-CE methods. Ultrasonic pulse-echo (UPE) was used to test the flaws in the specimens. The delaminations were created by applying expansive mortar in prepared through holes. Three specimens with two delaminations each were built and tested using UPE.

The Difference of Antioxidants Activity between Methanol Extract and Ethanol Extract of Bay Leaves (Syzygium polyanthum (Wigh) Walp) USED DPPH Method (1,1-difenil-2-pikrilhidrazil)

Antioxidant are compounds that can inhibit oxidant by reacting with reactive of free radicals to form non reactive free radicals that was relatively stable. One of the natural antioxidants derived from plants is salam leaf. Salam leaf (Syzygium polyanthum (Wigh) Walp) has the chemical content of polyphenol compounds such as flavonoids and tannin its efficacious is as antioxidants. The aims of this research is to determine whether there is a reaction on antioxidant activity of ethanol extract and methanol extract of salam leaves, as well as to know whether there is a difference of antioxidants activity between the ethanol extract and methanol extract. The extraction of salam leaves is done by maceration method using liquid extraction 70% ethanol and methanol. The ethanol extract and methanol extract of salam leaves is made by the concentration 0,06%; 0,08%; 0,10%; 0,12%; 0,16% and its antioxidants power is being tested with DPPH. The antioxidants activity is determined by DPPH method with spectrofotometry UV-Vis till gets value EC50. This value EC50 is reached through the linear regression equation which states the relationship between the concentration of test solution (x) with the antioxidant activity (y) of a series of replicate measurements. The quantitative test results show that the average value EC50 for the ethanol extract of salam leaves is 14,2168 µg/ml and methanol extract of salam leaves is 12,4338 µg/ml. From the test results of “t” test in EC50 shows significant value 0,188 > 0,05 difference between ethanol extract (α value) which means that there is no significant difference between ethanol extract and methanol extract of salam leaves.

Do it in a different way: use a TDS meter to determine the colour degradation of dye solutions

This study demonstrated how a dye solution’s per cent colour degradation (η) may be calculated using the total dissolved solids (TDS) meter. As test solutions, varied concentrations of the brilliant blue solutions were utilised. We compared the results of TDS meter readings for per cent degradation with those of standard spectrometer measurements. The results of our measurements agree with those of a spectrometer. Therefore, TDS meters can be used as an option to measure colour degradation, particularly in laboratories lacking a spectrometer, considering that the price of a TDS meter is much more affordable than that of a spectrometer. A TDS meter with high accuracy must be used for scientific purposes demanding highly precise measurement findings.

Ipar 4.0 szemléletű tesztelés és validálás kialakításának hatásai az elektronikai gyártásban

The continuous demand increase of electronic items challenges the electronic manufacturing companies. The economic and manufacturing challenges, and the Industry 4.0 based solutions of having a great product portfolio of a regional, original equipment manufacturer are presented in this study. The acquirement and the implementation of the principles of Industry 4.0 results a new production environment, but the positive effects of that can be demonstrated from financial and production efficiency sides. The mindset change of the test and validation area of an electronic company, and the steps required to achieve Industry 4.0 based test solutions are presented in this article. You can read about the practical implementation of a pioneering technology in the field of informatics, Big Data oriented data processing in a real manufacturing environment. The changes related to hardware and software design and data acquisition are presented, also you can read about the resulting cost saving, production efficiency improvement and product output growth of the study.

A Densitometric Method for Determination of Mangiferin, an Antioxidant Compound, with Thin Layer Chromatography in the Leaf Extracts of Coffee (Coffea Arabica L.)

Mangiferin is one of the antioxidants in Coffea arabica L. leaves that has many pharmacological effects. The content of secondary metabolites in the leaves including mangiferin can be affected by age. A Thin Layer Chromatography (TLC) method for the quantitative analysis of mangiferin in Coffea arabica L. leaves extract was developed and validated. The method was developed using a mobile phase prepared with analytical grade solvents: ethyl acetate, methanol, formic acid, and deionized water (8:2:1:1 v/v/v/v). Regression functions were established over the 199.98-600.00 ng/spot range with r=0.999. The limit of detection (LOD) and limit of quantification (LOQ) were 13.87 and 41.61 ng, respectively. The method was selective with a resolution value of more than 1.5 and specific with the spectra correlation value for purity and identity check of more than 0.99. The percentage RSD was found to be 2.43% for repeatability precision and 2.05% for intermediate precision. The method's accuracy was determined through the standard addition method by adding known quantities of standard mangiferin to the pre-analyzed test solution and the mean recovery was 101.69± 1,21%. This TLC Densitometry method was linear, sensitive, selective and specific, precise, accurate, and can be used for routine analysis of mangiferin. On the young Coffea arabica L. leaves, the concentration of mangiferin ± RSD was 0.830 ± 1.71% w/w, and on the old Coffea arabica L. leaves was 1.128± 1.59% w/w.

Acute toxicity tests of TEMPO-oxidized cellulose nanofiber using Daphnia magna and Oryzias latipes

Ecotoxicity data on cellulose nanofibers (CNFs) are limited despite their wide application prospects. Herein, acute toxicity tests of 2,2,6,6-tetramethylpiperidine-1-oxyl radical (TEMPO)-oxidized CNFs to Daphnia magna and Oryzias latipes were conducted according to the Organisation for Economic Co-operation and Development test guidelines, which consider CNF dispersibility during the test. To select a suitable test medium, the interaction between the medium components and CNFs was first evaluated using five test media with different ion concentrations. The viscosity, zeta potential, and concentration uniformity of TEMPO-CNFs changed with increasing ionic concentration. The toxicity test results showed no acute toxicity of TEMPO-CNFs to the two species, even at the highest exposure concentrations in this study. Both the median effective concentration (EC50) and median lethal concentration (LC50) were >100 mg/L. In most cases, the measured CNF concentrations were within 20% of the nominal concentrations and remained largely constant. However, in the D. magna acute toxicity test, the concentration uniformity of TEMPO-CNFs tended to decrease when the CNF concentration was low. Our results demonstrate the importance of measuring CNF concentrations during testing and revealed that the ion concentrations in the test solution changed because of the interaction between the medium components and TEMPO-CNFs. This finding demonstrates the importance of examining the components of the medium to avoid mistaking the effects of depleted medium components for the direct effects of TEMPO-CNFs on aquatic organisms.

OBTAINING A WORKING STANDARD SAMPLE OF CHALCONE BUTEINE AND ITS QUANTITATIVE DETERMINATION IN PLANT RAW MATERIALS

Introduction. Butein ‒ 2',4',3,4-tetrahydroxychalcone is found in a number of plants that have a pronounced antimicrobial and antifungal effect: Butea monosperma Lam., hairy string ‒ Bidens pilosa L., tripartite string ‒ Bidens tripartita L., hydrophytum ‒ Hydnophytum formicarum Jack., early thyme ‒ Thymus praecox. Butein is not the dominant representative of the flavonoid class in plants, but it can serve as a marker compound for the analysis of raw materials containing this chalcone. The purpose of the study is to synthesize and analyze a working standard sample of butein, as well as to develop a method for its quantitative determination in Cosmos bipinnate raw materials using solid-phase extraction. Material and methods. Butein synthesis was carried out using the Claisen‒Schmidt reaction, the yield was 44,4%. Identification of the obtained butein was carried out using UV, IR and Mass spectroscopy. Quantitative determination of butein in the raw materials of Cosmos doubly persita was carried out by HPLC in combination with solid-phase extraction. Results. The results obtained confirm that the test sample is butein (2',4',3,4-tetrahydroxychalcone). To determine butein in plant raw materials, a standard sample of this compound should be available, and therefore the substance of this chalcone was synthesized and on its basis, according to the state pharmacopoeia, a working standard sample was obtained (butein content in it is 99,62%). Identification of butein by HPLC was carried out by the retention time, which in the chromatogram of the test solution is 160,70 min, in the chromatogram of the standard solution – 160,07 min  2%. The butein content in the flowers of the cosmos bipinnate we studied in terms of dry raw materials is 0,043%  2%. Conclusions. The synthesis of chalcone ‒ butein was carried out by alkaline condensation of resacetophenone with protocatechuic aldehyde. The yield of butein is 5,95  0,0195 g (44,4%). A working standard sample was obtained based on the butein substance, the authenticity and purity of which was confirmed by melting point, as well as using HPLC, mass spectroscopy, UV and IR spectroscopy. The resulting standard working sample was further used to develop a method for the quantitative determination of butein in Cosmos bipinnate flowers using solid-phase extraction. The butein content in terms of dry raw materials is 0,043%3%.

A high sucrose detection threshold is associated with increased energy intake and improved post-prandial glucose response independent of the sweetness intensity of isocaloric sucrose solutions

Several studies proposed a role for the sweet taste receptor in energy intake and blood glucose regulation, but little is yet known about the impact of the individual sweet taste perception. Here, we found in a cross-over human intervention study with 29 male participants that modulating the sweetness of an isocaloric sucrose solution did not influence postprandial plasma concentrations of blood glucose and associated hormones over 120 min and 2 h post-load energy intake. Independent of the sweetness of the test solution, tests persons with a higher sucrose detection threshold had an average of 402 ± 78.8 kcal (39 ± 21%) higher energy intake and a higher glucose/insulin ratio, combined with a higher liking for sweet tasting food, than the test persons of the low threshold group. The body composition suggested a higher fat-free mass in the high threshold group that may have influenced energy intake and post-prandial glucose responses.

Corrosion Investigation by Scanning Electrochemical Microscopy of AISI 446 and Ti-Coated AISI 446 Ferritic Stainless Steel as Potential Material for Bipolar Plate in PEMWE

AbstractThe components of proton exchange membrane water electrolysers frequently experience corrosion issues, especially at high anodic polarization, that restrict the use of more affordable alternatives to titanium. Here, we investigate localized corrosion processes of bare and Ti-coated AISI 446 ferritic stainless steel under anodic polarization by scanning electrochemical microscopy (SECM) in sodium sulphate and potassium chloride solutions. SECM approach curves and area scans measured at open-circuit potential (OCP) of the samples in the feedback mode using a redox mediator evidence a negative feedback effect caused by the surface passive film. For the anodic polarization of the sample, the substrate generation-tip collection mode enables to observe local generation of iron (II) ions, as well as formation of molecular oxygen. For the uncoated AISI 446 sample, localized corrosion is detected in sodium sulphate solution simultaneously with oxygen formation at anodic potentials of 1.0 V vs. Ag/AgCl, whereas significant pitting corrosion is observed even at 0.2 V vs. Ag/AgCl in potassium chloride solution. The Ti-coated AISI 446 sample reveals enhanced corrosion resistance in both test solutions, without any evidence of iron (II) ions generation at anodic potentials of 1.2 V vs. Ag/AgCl, where only oxygen formation is observed.

Retracted: Development and Implementation of a Low-Cost Test Solution for High-Precision ADC Chips Based on Intelligent Sensor Networks

Retracted: Development and Implementation of a Low-Cost Test Solution for High-Precision ADC Chips Based on Intelligent Sensor Networks

An Integrated and Fully Automated Test Solution for Automotive Cameras of Ultrawide Angle of View

An Integrated and Fully Automated Test Solution for Automotive Cameras of Ultrawide Angle of View

The Autocatalytic Chemical Reaction of a Soluble Biopolymer Derived from Municipal Biowaste.

The paper discusses the perspectives of further implementation of the autocatalytic properties of a soluble biopolymer (SBP) derived from municipal biowastes for the realisation of a biorefinery producing value-added bio-products for consumer use. The reaction of an SBP and water is reported to cause the depolymerisation and oxidation of the pristine SBP organic matter with the formation of carboxyl-functionalised polymers having lower molecular weight and CO2. These findings demonstrate the oxidation of the SBP via water, which could only occur through the production of O and OH radicals catalysed by the SBP. According to the adopted experimental plan, the anaerobic digestate supplied by an Italian municipal biowaste treatment plant was hydrolysed in pH 13 water at 60 °C. The dry product was re-dissolved in plain water at pH 10 and used as a control against the same solution with hydrogen peroxide at 0.1-3 H2O2 moles per SBP carbon mole added. The control and test solutions were kept at room temperature, in the dark or in a climatic chamber under irradiation with simulated solar light, until the pH of the solutions remained constant. Afterwards, the solutions were processed to recover and analyse the crude soluble products. The present work reports the results obtained for the control solution and for the test solutions treated in the presence and absence of H2O2, with and without pH control, in the dark and under irradiation with simulated solar light.

Toxicological assessment of synthetic pesticides on physiology of Phaseolus vulgaris L. and Pisum sativum L. along with their correlation to health hazards: A case study in south-west Nagaland, India

Pesticide toxicity has been a major concern in the recent time. Higher concentrations of pesticides affect the organisms and environmental health. The present study aims to assess the toxicological effect of some commonly used pesticides in southwest Nagaland of India and their impact on the physiology of Phaseolus vulgaris and Pisum sativum along with their correlation to health hazards. The study area is a hilly region where the overall temperature ranges in between 2 °C and 35 °C. The annual rainfall received in the region is between 1000 and 2000 mm. The region shares a subtropical to tropical climate. Agriculture is the main activity of the region. Seeds of Phaseolus vulgaris and Pisum sativum were collected from the local market and sterilized with 2 % sodium hypochlorite for 15 min. The solution of monocrotophos, chlorpyrifos, dimethoate, dichlorvos, and cypermethrin was prepared with 1 ppm, 10 ppm, 50 ppm, and 100 ppm concentrations. The seeds were soaked for 24 h in the test solutions and kept uniformly in sterilized petri dishes in 10 ml of test solutions. For every experiment, three replicates of each sample were taken including the control. The control sample was run with tap water. For each replica 10 seeds were taken, so one sample contained 30 seeds. The seeds of the above two vegetable species were treated with these pesticides and analyzed for germination rate, phytotoxicity, dry biomass, and seedling vigor index. The result has shown the negative impact of higher concentrations of pesticides on plant physiology. A questionnaire and interview-based field survey were also conducted among the users to find out exposure-related health hazards of pesticides. The average time utilized for a single interview was 30 min. According to the self-assessed reports of 323 pesticide users, 17 physical disorders were recorded from the study. Eye irritation (49.12), excessive sweating (46.68), and excessive tiredness were some of the highly observed signs and symptoms among the users. For the statistical analysis, analysis of variance (ANOVA) for the biomass production in radicle and plumule of the studied species was done with OriginPro 8.5 software. A chi-square (χ2) test was performed at the significance level of 5 % for the comparative study among male and female farmers for exposure-related disorders. The correlation analysis was done with MS-EXCEL software. A coefficient correlation value of 0.54 was recorded, which indicates a positive correlation between the studied factors.

Larvacidal effects of methanolic and ethanolic leaf extracts of <i>Xienemia americana</i> against female <i>Anopheles gambiae</i> S.L. (Culicidae: Diptera)

Anopheles gambiae complex is the most important vector of malaria in sub-Saharan Africa. It is thought that Nigeria comprises about 45 species of Anopheles mosquitoes of which Anopheles gambiae is the most prevalent. Extract of different concentrations were evaluated at the level of 2.00 3.00, 4.00, 5.00 and 0.00 (Control) mg/ml. Distilled water only was used as control. Twenty (20) larvae were put into four (4) cups containing 100ml of the test solution of each concentration. Larval to pupa mortality were recorded and calculated after 24, 48 and 72h after treatment. Mortality results were used to determine LC50 and LC90 using probit analysis. The larvicidal activity of methanol and Ethanolic extracts of the X. Americana were evaluated on 4th instar larvae of Anopheles gambiae. From the results concentration of X. americana with ethanol has shown high larvicidal effect with 10%, 12%, 3% adult emergence when compare with control. While Methanol concentration reveals low larvicidal effect with 16 % adult emergence. Treatment group X. Americana showed highest survival from pupa to adult (28, 18% and 6%) recorded, this means concentration of ethanol has larvicidal effect against A. gambiae. However, methanol concentration shows low activity with 45, 21 and 16% followed by X. Americana with 18, 15 and 10% recorded the highest larvicidal activity among all the concentrations with methanol respectively. Concentration of 5.0 mL, 12.0 mL, 20.0 mL, 25.0, 30.0mL compare to control group. All the extracts proved to be toxic to the test organism, though there was a remarkable difference in the concentrations and timing of their activity.

Characterization Using Point Defect Theory of the Microstructure Effect on Passivity Stability in Austenitic Stainless Steel

The influence of the microstructure on the resistance to pitting potential in austenitic stainless steel UNS S31603 is evaluated to explain the effect of the distribution of features such as carbides. Different microstructures were obtained by processing, via surface laser melting (SLM) and sensitized at 600°C, 700°C, and 800°C. The test solution used for electrochemical testing included a buffer pH 8 brine at room conditions. The characterization of the passive conditions is done by using potentiodynamic, potentiostatic, and Mott Schottky techniques. The results show that the UNS S31603 samples produced by SLM have higher passive layer stability. The correlation with the microstructural features attributes this to a lack of inclusions and carbides characteristic of the SLM process. The analysis of the experimental results using the point defect model description of the passive layer behavior indicates that the stability of the passive layer is a priori inversely proportional to both the metal cation and anion vacancy diffusivities. Experiments reveal the close dependence and explain the properties of the passive layer with respect to a point defect model.

A Review of Over-the-Air Testing Methods for Performance Measurement of Antennas and Devices in Communication Systems

With the fast development of communication techniques, over-the-air testing has developed into the main testing method for current communication systems due to its advantages including no cable connection, high measurement efficiency, and independence from environment. OTA testing has become almost the only solution for 5G system testing especially after the popularity of 5G massive multiple-input-multiple-output. In this paper, we summarize the three main methods of OTA testing including the reverberation chamber-based method, the radiation two-step method, and the multiprobe anechoic chamber- (MPAC-) based method, among which we focus on the MPAC method systematically. In the MPAC method, there are two main channel synthesis techniques that have been heavily studied, namely, prefaded signal synthesis and plane wave synthesis. We summarize the current main research based on these two techniques including probe configurations, probe selection algorithms, and probe design based on the PFS technique and the design of plane wave generators based on PWS technique. The main comparisons are made for the performance of different probe selection algorithms and the performance of different plane wave generators as well as the latest advances.

Impact of Sorts Disinfection and Cleansing Material on Hardness of Different Types of Denture Base Material

Dentist, dental technician and assistants are faced a several kinds of microorganisms during wor like bacteria, fungi and viruses .So, we can prevent cross contamination by using either chemica or mechanical disinfection. The aim of the research was to measure the effect of different types of chemical disinfection on the hardness of two types of denture base resin, heat activated acry and nylon (flexible). A total number of 80 denture resin specimens (40 specimens from hea activated acrylic and 40 specimens from flexible resin) were prepared. Each type of specim was subdivided into 4 groups. Three groups were divided according to the type of dentur disinfectants (1%sodium hypochlorite, 1% povidine/iodine, Kin solution) and the fourth whi considered as control group was immersed in distilled water. All specimens were immersed testing solution for 90 minutes at 370C. The hardness of the specimens before and af immersion was tested using Shore D machine. Our study showed that the mean value hardness test for poly methyl methacrylate higher than polyamide and there need aid non significant Contrast in the resistance of the surface to scratches and indentation between diver sorts of thermoplastic resin after using chemical disinfectant and denture cleansers w i comparison with control group for each type of denture base resin. The resistance to indentati of different types of denture base would not affected by short time immersion in chemica disinfectant.

New Test Solution for Cyclic Corrosion Test Reproducing Atmospheric Corrosion Behaviors of Steel and Zinc in Coastal Area

New Test Solution for Cyclic Corrosion Test Reproducing Atmospheric Corrosion Behaviors of Steel and Zinc in Coastal Area

Portable Nanopore sequencing solution for next-generation HIV drug resistance testing

BackgroundTackling HIV drug resistance is one of major challenges for ending AIDS epidemic, but the elevated expense of cutting-edge genomics hampers the advancement of HIV genotype testing for clinical care. MethodsWe developed a HIV genotype testing pipeline that centers on a cost-efficient portable Nanopore sequencer. Accuracy verification was conducted through comparison with parallel data obtained via fixed-site Pacbio sequencing. Our complete pol-gene sequencing strategy coupled with portable high-throughput sequencing was applied to identify drug resistance mutations across 58 samples sourced from the ART-treated Los Angeles General Medical Center Rand Schrader Clinic (LARSC) cohort (7 samples from 7 individuals) and the ART-naïve Center for HIV/AIDS Vaccine Immunology (CHAVI) cohort (51 samples from 38 individuals). ResultsA total of 472 HIV consensus sequences, each tagged with a unique molecular identifier, were produced from over 1.4 million bases acquired through portable Nanopore sequencing, which matched those obtained independently via Pacbio sequencing. With this desirable accuracy, we first documented the linkage of multidrug cross-resistance mutations across Integrase Strand Transfer inhibitors (INSTIs) and Non-Nucleoside Reverse Transcriptase Inhibitors (NNRTIs) from an individual failing a second-generation INSTI regimen. By producing more than 500 full-length HIV pol gene sequences in a single portable sequencing run, we detected Protease Inhibitor (PI), Nucleoside Reverse Transcriptase Inhibitor (NRTI), NNRTI and INSTI resistance mutations. All drug resistance mutations identified through portable sequencing were cross-validated using fixed-site Pacbio sequencing. ConclusionsOur accurate and affordable HIV drug resistance testing solution is adaptable for both individual patient care and large-scale surveillance initiatives.

Slurry and liquid impingement erosion behavior of low-temperature plasma carburized AISI 420 martensitic stainless steel

The impact of plasma carburizing treatment on the erosion wear resistance of AISI 420 martensitic stainless steel (MSS) was studied. Experiments were carried out varying a broad spectrum of erosion parameters, including impact velocity, impact angle, and exposure duration. Both slurry and liquid impingement erosion were employed in the experiments, with testing conducted using both distilled water and saline solutions to assess the combined effects of corrosion and erosion wear. Compared to untreated samples, a significant improvement in the erosion wear resistance of AISI 420 MSS due to low-temperature plasma carburizing treatment was observed for all tested conditions. The observed performance enhancement can be attributed to the formation of the carburized layer, constituted of the α'C and Fe3C phases. Results also highlighted that the severity of the tribosystem was significantly influenced by the test solution characteristics. A marginal increase in severity was observed upon introducing the saline solution, while a more substantial severity increase occurred with the addition of solid particles in the test fluid. The specimens' mass loss was increased by increasing impact velocity, following a simple potential relationship, and with impact angle, following a first-degree linear equation. In the case of the exposure time, the mass loss curves depended on the test environment. For solutions containing quartz particles, an additional final stabilization stage was observed in addition to the acceleration stage observed in the absence of abrasive component. This phenomenon was attributed to surface work hardening induced by the impact of solid particles. Regarding wear mechanisms, samples tested only with distilled water displayed erosion flow marks. Those containing distilled water and NaCl exhibited not only flow marks but also pits. Lastly, solutions containing solid particles additionally presented features of plastic deformation, lip formation, craters, indentations, and extruded material.