Increase In pH Levels Research Articles

Synthesis of Hydrogel Based on Poly (Acrylic Acid–Co‐Vinyl Acetate) Grafted on Modified Recycled Cellulose for Use in Fertilizer Slow‐Release System

The aim of this work is a synthesis of suitable hydrogel to produce slow‐release fertilizer using recycled cellulose which is obtained from waste paper. For this purpose, initially, we extracted alpha cellulose from waste paper and modified it to obtain carboxymethyl cellulose (CMC). Then, the CMC was converted to a suitable hydrogel through in situ graft copolymerization of acrylic acid and vinyl acetate in the presence of methylene bisacrylamide as a crosslinker. The various factors that affect hydrogel synthesis, such as the amounts of CMC, monomers, initiator, and crosslinker, were evaluated. In the optimized formulation, the weight ratio of monomers to CMC is 7, the molar ratio of monomers to each other is 1, and the crosslinker is used as 3 molar percent of monomers. The products were characterized using Fourier transform infrared, thermal gravimetric analysis, and scanning electron microscope analyses. The swelling behavior of the synthesized hydrogels was evaluated in different environments, such as distilled water, tap water, salt water, and different pH levels. The swelling ratio increases with an increase in pH level. Between the synthesized hydrogels, the best one was selected for slow‐release fertilizer production and loaded with 20‐20‐20 fertilizer (NPK), and the release behavior was evaluated. In an alkaline pH, there was a long time for NPK release within a slow‐release medium and even after 361 h, the release process was continued. Also, the performance of the fertilizer‐loaded hydrogel in soil using water holding capacity and water retention ratio tests were evaluated.

ANALYSIS OF THE IMPACT OF BASE PLASTICS ON ORAL FLUID INDICATORS IN PATIENTS WEARING PARTIAL REMOVABLE DENTURES

The purpose of the study is to carry out a comparative evaluation of the analysis of the impact of partially removable dentures on the parameters of the oral fluid in individuals undergoing orthopedic rehabilitation with partial removable dentures.
 Materials and Methods: To ensure the objectivity of our results, patients aged 46 to 72 years were divided into two groups: I group – control (n=22) and II group – main (n=24). Each group was further subdivided into subgroups including primary prosthetic patients and secondary prosthetic patients. The control group received partial removable constructions made from standard domestic hot polymerization plastic, while the main group underwent orthopedic treatment using advanced techniques and newly developed domestic cast plastics. To assess the interaction between acrylic plastic removable prostheses and the oral tissues during the period of patient’s adaptation to the prostheses, we conducted biophysical studies of oral fluid both before treatment and one month after wearing prosthesis.
 Results: This study revealed a significant (p < 0.001) increase in pH levels in the primary control group, rising by 2.7% from (6.12±0.03) units to (6.29±0.05) units after treatment. The secondary prosthetic control group also saw a slight pH increase, from (6.16±0.04) units to (6.22±0.06) units, with no significant difference between these parameters (p > 0.05).
 Conclusions: The results obtained from our improved treatment method suggest a positive impact on oral fluid parameters during the stages of treatment with partial removable lamellar prostheses. Patients in the main group experienced no significant disruptions in their oral fluid, which directly influences their adaptation to removable structures and overall quality of life.

Impact of pH levels on the morphological, dielectric and impedance spectral behaviour of cobalt oxide nanomaterials

Pure Co3O4 nanomaterials were synthesized by using Sol-Gel technique at various pH levels (7, 8 and 9). Morphological and structural analysis was done by X-ray diffraction method (XRD), scanning electron microscope (SEM) and energy-dispersive spectroscopy EDX. The X-ray diffraction patterns revealed that the prepared samples crystallized in a cubic structure without any impurities. SEM micrographs validated the influence of pH in altering the morphology of the synthesized compound. The elemental spectrum analysis EDX confirms the presence of cobalt and oxygen without any impurities. Variation of dielectric constant, dielectric loss and impedance were analyzed for various temperatures and different pH values. Dielectric loss value increases at high temperature due to the thermal disturbance of the atoms. Cole-Cole impedance plot gives the information about grain and grain boundaries. DC electrical conductivity values of Co3O4 nanomaterials in the temperature range 40ºC to 250ºC increases with increase in pH level from 7 to 9. Arrhenius plot of Co3O4 nanoparticles confirmed that the activation energy at various temperature increases with increase in pH levels upto 8, then decreases for pH level 9.

Effect of pH on the Mycelial Growth of Aspergillus niger and Aspergillus flavus

Aspergillus fungus is well-known for causing a number of secondary plant and food rots that can result in the buildup of mycotoxins, despite their significant economic contribution to the fermentation industries. In the past, even the most fundamental influences on the development and inhibition of significant mycotoxigenic fungi were only partially understood. To overcome this issue, an investigation on the impact of pH on the mycelial development of Aspergillus species was conducted. A. niger and A. flavus were inoculated in PDA medium with a range of pH values from 4.0 to 9.0 under in vitro conditions and then cultured for 7 days at room temperature. Results revealed that, the mycelial growth of A. niger and A. flavus was increased with increase in pH level up to 6 and then became static up to pH level 9 and there was no mycelial growth in pH 4. Hence, it was concluded that the use of alkaline compounds as a way of preventing their proliferation and reproductive processes may be used to inhibit the development and spore production of A. niger and A. flavus, which can affect the crops.

Soil attributes and their interralationships in Rio Grande do Sul

The present study aimed to highlight and understand the dynamics of interaction of the levels of soil parameters that are determinant for the expression of crop productivity. The study took place in seven municipalities in the northwest of the state of Rio Grande do Sul (Barra do Guarita, Braga, Derrubadas, Miraguaí, Redentora, Tenente Portela, and Vista Gaúcha), in the year 2017/2018. Soil samples were collected in these environments, with a total of 67 soil samples. Most of the studied soils presented pH above 5,5 with 79% of the samples with CEC between 12 and 18. The values of base saturation in 82% of the soils presented values of 80%, while, for of aluminum saturation, in 87% of the samples the values were 0. As for the contents of organic matter, 60% of the soils presented contents above 2,5% with high and low levels of potassium and phosphorus, respectively. When the levels of potential acidity increase, consequently, there is a reduction in the availability of the main nutrients, micronutrients and the Ca:K ratio. On the other hand, when there is an increase in pH levels, there is a greater availability of nutrients and a reduction in potential acidity and aluminum levels.

Effects of UV-C Irradiation and Vacuum Sealing on the Shelf-Life of Beef, Chicken and Salmon Fillets.

One-third of the world's food supply is lost, with meat being a major contributor to this loss. Globally, around 23% of all meat and 35% of all seafood products are lost or wasted. Meats and seafood products are susceptible to microbial spoilage during processing, storage, and distribution, where microbial contamination causes significant losses throughout the supply chain. This study examined the efficacy of UV-C irradiation and vacuum-sealing in preventing microbiological deterioration in beef, chicken, and salmon fillets. The samples were sterilized using a constant UV-C irradiation dose of 360 J/m2 and stored under a reduced pressure of 40 kPa. A microbiological analysis was conducted daily to examine the microbial contamination, which included counting the colonies of Pseudomonas spp., aerobic bacteria, lactic acid bacteria (LAB), Salmonella, and Escherichia coli, as well as monitoring the increase in pH levels. The results demonstrated a statistically significant difference (p > 0.05) in the aerobic bacteria counts between the storage conditions and storage days in all samples, which is a primary indicator of microbial spoilage. In contrast, the differences varied in the Pseudomonas spp. and LAB counts between the storage conditions and storage days, and there was no significant difference (p < 0.05) in the pH levels between the storage conditions. The results indicate that the combination of UV-C irradiation and vacuum sealing effectively inhibits microbial growth and extends the shelf-life of beef, chicken, and salmon fillets by 66.6%.

Implementation of Circular Economy in Peatlands to Support Sustainable Food Security in Post Covid-19 Era

The peatlands in Indonesia have changed quite a lot in recent years due to over-exploitation and climate change. The land-use change on peatlands resulted in soil infertility. The impacts of the degradation of peatlands are almost certain to worsen with the COVID-19 pandemic because the peatlands have an important role in providing food resources. Therefore, the peatlands restoration must be carried out considering the importance of the peatlands as food resources and carbon capture. One of the alternative solutions is to recycle the waste from agroforestry into organic fertiliser. This study aimed to investigate the application of organic fertiliser to restore soil fertility in the peatlands. The study also offered the circular economy scheme that can be applied in the peatlands to restore sustainability. The results showed that the degraded peatland that has been restored by adding organic fertiliser from local sources has a higher soil pH level than the one without adding organic fertiliser. The increase in pH level can decrease soil hydrophobicity and increase microorganism activities, encouraging biodiversity in the peatlands. In this study, the circular economy scheme by the integration between agroforestry and livestock was assessed economically and environmentally. Recycling cows’ manure and leaf litter from peatlands into energy and recycling biogas sludge into biochar for biogas purification and soil enrichment benefit economically and contribute to mitigating greenhouse gas emissions.

The hydroperoxyl antiradical activity of Trolox in water: The effects of pH values on rate constants

Abstract Trolox (6-hydroxy-2,5,7,8-tetramethylchromane-2-carboxylic acid) is a highly hydrophilic α-tocopherol analog that is widely used as a standard against which the antioxidant ability of other chemicals is measured and represented in Trolox equivalents. However, the effect of pH values on the hydroxyl radical scavenging activity has not been fully studied yet. In this study, the HOO• antiradical activity of Trolox in water was studied. It was found that the H-abstraction of the O1-H bond determined the activity of the neutral and monoanion states, whereas the electron transfer reaction of the hydroxyl anion state determined the activity of the dianion state. Although the total rate constant increased following the increase in pH levels, the overall rate constant of the Trolox + HOO• reaction in water changed when pH levels rose due to the decrease in HOO• molar fraction. The results also revealed that at pH &lt; 2, the O1-radical was the main intermediate of the Trolox + HOO• reaction in water, whereas, at pH ---gt--- 5, the anion-radical was the significant intermediate. Thus the rate constants and the reaction intermediates vary with the pH values.

Effects of Fluoride and Calcium Phosphate-Based Varnishes in Children at High Risk of Tooth Decay: A Randomized Clinical Trial.

Background: The aim of this study was to investigate the effect of the application of two varnishes—MI Varnish (5% sodium fluoride with CPP-ACP) and Clinpro White Varnish (5% sodium fluoride with fTCP)—applied every three months in children with high caries risk for 12 months on plaque indexes, salivary pH, salivary lactic acid and chemical elements concentrations. Methods: We included 58 children aged 4–12 years, assigned to control (placebo), Clinpro and MI groups. Baseline and three-month saliva samples were taken. We assessed changes in pH, lactic acid concentrations and chemical elements in saliva. Results: At 12 months, all groups showed a nonsignificant increase in pH levels and a reduction in lactic acid, which was greatest in the placebo group. There was a significant reduction in 24Mg (p = <0.001), 31P (p = 0.033) and 66Zn (p = 0.005) levels in the placebo group (p ≤ 0.05), but not in the other elements studied: 23Na, 27Al, 39K, 44Ca, 52Cr, 55Mn, 57Fe, 59Co, 63Cu, 75As, 111Cd, 137Ba, 208Pb and 19F. Conclusions: Neither pH, lactic acid concentrations or most salivary chemical elements were useful in defining patients at high risk of caries or in monitoring the effect of MI Varnish and Clinpro White Varnish after three-month application for 12 months. However, the appearance of new cavities was stopped, and the hygiene index improved, probably due to hygienic and dietary measures and the use of fluoridated toothpaste. Trial registration: ISRCTN registry, ISRCTN13681286.

Study of the impact of amino acids hydrochloride forms on the formation of biomimetic composites in the presence of nanocrystalline hydroxyapatite

The study of molecular composition of the biomimetic composites on the basis of nanocrystalline carbonate-substituted (C-HAP) and polar amino acids of L-lysine hydrochloride and L-arginine hydrochloride was performed in the work. Results of the study show that the change in acidity of the medium (pH≥11.2, ≥7.55 и ≤5) occurs under transformation of the conformational environment of L-lysine hydrochloride molecules with the formation of L-lysine structure as while increase of pH level as in the presence of C-HAP nanocrystals. At the same time composites basing on L-arginine keep their amorphous structure in the presence of synthesized C-HAP in the different media. The detected differences in the molecular environment of hydrochloride forms of amino acids during the interaction with nanocrystalline C-HAP prove to be significant for the development of technology of the integration between biocomposites and hard dental tissues.

Dopaminergic Signaling in the Nucleus Accumbens Modulates Stress-Coping Strategies during Inescapable Stress.

Maladaptation to stress is a critical risk factor in stress-related disorders, such as major depression and post-traumatic stress disorder (PTSD). Dopamine signaling in the nucleus accumbens (NAc) has been shown to modulate behavior by reinforcing learning and evading aversive stimuli, which are important for the survival of animals under environmental challenges such as stress. However, the mechanisms through which dopaminergic transmission responds to stressful events and subsequently regulates its downstream neuronal activity during stress remain unknown. To investigate how dopamine signaling modulates stress-coping behavior, we measured the subsecond fluctuation of extracellular dopamine concentration and pH using fast scanning cyclic voltammetry (FSCV) in the NAc, a postsynaptic target of midbrain dopaminergic neurons, in male mice engaged in a tail suspension test (TST). The results revealed a transient decrease in dopamine concentration and an increase in pH levels when the animals changed behaviors, from being immobile to struggling. Interestingly, optogenetic inhibition of dopamine release in NAc, potentiated the struggling behavior in animals under the TST. We then addressed the causal relationship of such a dopaminergic transmission with behavioral alterations by knocking out both the dopamine receptors, i.e., D1 and D2, in the NAc using viral vector-mediated genome editing. Behavioral analyses revealed that male D1 knock-out mice showed significantly more struggling bouts and longer struggling durations during the TST, while male D2 knock-out mice did not. Our results therefore indicate that D1 dopaminergic signaling in the NAc plays a pivotal role in the modulation of stress-coping behaviors in animals under tail suspension stress.SIGNIFICANCE STATEMENT The tail suspension test (TST) has been widely used as a despair-based behavioral assessment to screen the antidepressant so long. Despite its prevalence in the animal studies, the neural substrate underlying the changes of behavior during the test remains unclear. This study provides an evidence for a role of dopaminergic transmission in the modulation of stress-coping behavior during the TST, a despair test widely used to screen the antidepressants in rodents. Taking into consideration the fact that the dopamine metabolism is upregulated by almost all antidepressants, a part of which acts directly on the dopaminergic transmission, current results would uncover the molecular mechanism through which the dopaminergic signaling mediates antidepressant effect with facilitation of the recovery from the despair-like behavior in the TST.

Rapid destruction of triclosan by Iron(III)-Tetraamidomacrocyclic ligand/hydrogen peroxide system

Iron(III)-tetraamidomacrocyclic ligand (Fe(III)-TAML) activators can activate hydrogen peroxide to oxidize many kinds of organic pollutants. In this study, we investigated the degradation of triclosan, a widely used broad-spectrum bactericide, under the treatment of Fe(III)-TAML/H2O2 system at different pH conditions. We also studied the influence of natural organic matter (NOM) on the degradation process. Our results showed that complete removal of triclosan could be obtained within several minutes under the optimal conditions. The degradation of triclosan by Fe(III)-TAML/H2O2 system exhibited strong pH-dependence and the degradation rate increased with the increase in pH level from 7.0 to 10.0. When adding fulvic acid (FA) or humic acid (HA) in the reaction system, the degradation of triclosan could be suppressed slightly, and HA exhibited stronger inhibition than FA. Based on the analysis of reaction intermediates, phenoxyl radical reaction and ring open reaction were involved in the decomposition of triclosan. Significant inhibition of overall toxicity to Photobacterium phosphoreum further confirmed the high efficiency of Fe(III)-TAML/H2O2 system for the removal of antibiotic activities resulting from the parent triclosan molecule and its degradation products.

Application of FeIII-TAML/H2O2 system for treatment of fluoroquinolone antibiotics

Over the recent past, fluoroquinolone antibiotics (FQs) have raised extensive attention due to their potential to induce the formation of resistance genes and “superbugs”, thus various advanced oxidation techniques have been developed to eliminate their release into the environment. In the present study, the prototype tetraamido macrocyclic ligand (FeIII-TAML)/hydrogen peroxide (H2O2) system is employed to degrade FQs (i.e., norfloxacin and ciprofloxacin) over a wide pH range (i.e., pH 6-10), and the reaction rate increases with the increase in pH level. The effect of dosage of FeIII-TAML and H2O2 on the degradation of FQs is evaluated, and the reaction rate is linearly correlated with the added amount of chemicals. Moreover, the impact of natural organic matters (NOM) on the removal of FQs is investigated, and the degradation kinetics show that both NOM type and experimental concentration exhibit negligible influence on the oxidative degradation of selected antibiotics. Based on the results of liquid chromatography-high resolution mass spectrometry and theoretical calculations, the reaction sites and pathways of FQs by FeIII-TAML/H2O2 system are further predicted and elucidated.

Nitrogen Mineralization and Nitrification in Two Soils with Different pH Levels

ABSTRACTSoil pH is one of the properties that mostly influences nitrification rates, and can be used as a tool for controlling this process, seen that depending on its extent it may lead to nitrogen (N) losses and subsequent contaminations. The aims of this study were to evaluate mineralization and nitrification of two soils at different pH levels. The experimental design was factorial with two factors and three replicates, with the first factor referring to two samples of red latosols, one eutrophic (LV1) and the other dystrophic (LV2), and the second factor was soil’s pH, at six levels: 4.0, 4.5, 5.0, 5.5, 6.0, and 6.5. Samples were incubated for 70 days in laboratory conditions. Both nitrate (N-NO3) and mineral N contents were determined and adjusted to growth models. The eutrophic soil presented higher mineral N and N-NO3, and the increase of pH levels led to increases of both inorganic N and N-NO3contents. Increases in pH levels caused N-NO3levels to increase in both soils, however this occurrence happened because it increased the amount of mineralized N in the soil, seen that in all pH ranges in both soils practically all mineral N was in the form of N-NO3.

Synthesis, characterization and influence of pH on indium doped zinc oxide nanostructures

Indium doped zinc oxide (In:ZnO) nanostructures were synthesized using the refluxed sol-gel method at pH levels of 7, 8, 9, 10, 11 and 12 for the precursor solution, adjusted by the addition of aqueous sodium hydroxide to the solution mixture of zinc and indium salts. X-ray diffraction (XRD) patterns revealed intense diffraction peaks of wurtizite In:ZnO nanocrystals with increased broadenings due to the incorporation of larger size In3+ ions to the lattice sites of Zn2+ ions. The substitution process of the dopant ions into the lattice sites and the size of the crystallites were influenced and facilitated by the pH of the solution. The crystallite size decreased from 23 nm to 19 nm with an increase of pH level of the precursor solution. The micrograph from field emission scanning electron microscopy (FE-SEM) showed an aggregated mixture of spindle- and cone-like morphology which decreased in size as the solution pH increased. Transmission electron microscopy (TEM) also confirmed the morphology and the decrease in size of the structures obtained by FE-SEM measurements. The UV–Vis reflectance analysis also demonstrated that the optical properties of In:ZnO crystallites improved with the increase in pH of the solution, as shown by the blue shift of the absorption edge of the reflectance spectra. The energy band gap increased nearly linearly from 3.22 eV to 3.26 eV with the increased pH values from 7 to 12 which was attributed to the Burstein-Moss effect. Photoluminescence (PL) measurements show a significant change in the emission characteristics. Both excitonic and defect level emission bands were shifted to shorter wavelength as the pH level increased, verifying the widening of the energy band gap. The relative intensity ratios of excitonic to defect level emission bands (INBE/IDLE) decreased generally as the pH level increased, indicating the increased concentration of the defects of oxygen interstitials and vacancies in the produced nanostructures. All measurements exhibited in this study confirmed that increasing the alkalinity of the synthesis solution enhanced the production of highly crystalline In-doped ZnO nanostructures for a better and suitable material in the area of biomedical, solar cell and other optoelectronics applications.

Effects of precursor pH on structural and optical properties of CdTe quantum dots by wet chemical route

l-cysteine capped CdTe quantum dots (QDs) were synthesized in aqueous solution in open air. In order to improve the crystallinity of the CdTe QDs, synthesis conditions were optimized. Effects of different solution pH were investigated in order to determine the optimum pH for the growth of highly crystalline CdTe QDs. X-ray diffraction patterns (XRD) for all the as-prepared samples displayed a zinc blende crystal structure. The XRD peak intensities were found to increase to a certain pH level. This was accompanied by a general increase in the crystallite sizes (3.01–3.25 nm) of the CdTe QDs as the solution pH was gradually increased from 7 to 12.5. The calculated strain in the CdTe QDs was observed to decrease with an increase in the solution pH level. The morphological studies obtained from scanning electron microscope showed clear changes in the shape of CdTe QDs with various solution pH. The shape of the QDs changed from small spherical to large flower-like and needle-like structures for various solution pH. The optical spectroscopy studies revealed that the photoluminescence emissions were shifted to longer wavelength (545–593 nm) as the pH was increased from 7 to 12.5. The ultraviolet–visible analysis displayed a red shift in the absorption peaks with an increase in the pH levels. The optical band gaps obtained from the Tauc formula displayed an inverse relation with the solution pH which could be due to increase in the QDs’ sizes with increasing pH level.

Correction of the acid-base balance in the presence of the hypoxic-ischemic brain damage in newborns

One of the current problems of perinatal neurology is the hypoxic-ischemic brain damage in newborns associated with the influence of the hypoxia upon the fetus, intranatal and postnatal asphyxia on one hand and a lack of the efficient therapy schemes on the other hand. Due to this, the purpose of this pilotstudy isto identify the effects of drug Cytoflavin, included into the complex therapy scheme for the newborns with the cerebral ischemia of II-III stages, on the blood acid-base balance. A retrospective analysis of the results of the complex therapy for 16 newborns with the moderate (14 children) and severe (2 children) brain ischemia was performed. Cytoflavin was included in the standard therapy schemes for all children at a dose of 2 ml/kg per day at a dilution of 5% glucose solution at the ratio of 1:5, intravenously, microfluidically for 20 hours for 3 days. In addition to the standard examination, the blood acid-base balance assessment using the follow-up microgasometric method was included (after 60 min and then every 6 hours until 72 hours of observation). All children had positive tendency to the arresting of the metabolic acidosis (in the form of the decrease of the base deficiency after 24 hours and increase of pH level (the level of 7.30 was reached by 12 hours of age in full-term newborns and 24 hour of age in the preterm newborns). The revealed positive changes in the time of the metabolic acidosis arresting along with the small volumes of the infusion and good tolerability are the cause for the planning of the subsequent, more large-scale studies.

Regulating NETosis: Increasing pH Promotes NADPH Oxidase-Dependent NETosis

Neutrophils migrating from the blood (pH 7.35–7.45) into the surrounding tissues encounter changes in extracellular pH (pHe) conditions. Upon activation of NADPH oxidase 2 (Nox), neutrophils generate large amounts of H+ ions reducing the intracellular pH (pHi). Nevertheless, how extracellular pH regulates neutrophil extracellular trap (NET) formation (NETosis) is not clearly established. We hypothesized that increasing pH increases Nox-mediated production of reactive oxygen species (ROS) and neutrophil protease activity, stimulating NETosis. Here, we found that raising pHe (ranging from 6.6 to 7.8; every 0.2 units) increased pHi of both activated and resting neutrophils within 10–20 min (Seminaphtharhodafluor dual fluorescence measurements). Since Nox activity generates H+ ions, pHi is lower in neutrophils that are activated compared to resting. We also found that higher pH stimulated Nox-dependent ROS production (R123 generation; flow cytometry, plate reader assay, and imaging) during spontaneous and phorbol myristate acetate-induced NETosis (Sytox Green assays, immunoconfocal microscopy, and quantifying NETs). In neutrophils that are activated and not resting, higher pH stimulated histone H4 cleavage (Western blots) and NETosis. Raising pH increased Escherichia coli lipopolysaccharide-, Pseudomonas aeruginosa (Gram-negative)-, and Staphylococcus aureus (Gram-positive)-induced NETosis. Thus, higher pHe promoted Nox-dependent ROS production, protease activity, and NETosis; lower pH has the opposite effect. These studies provided mechanistic steps of pHe-mediated regulation of Nox-dependent NETosis. Raising pH either by sodium bicarbonate or Tris base (clinically known as Tris hydroxymethyl aminomethane, tromethamine, or THAM) increases NETosis. Each Tris molecule can bind 3H+ ions, whereas each bicarbonate HCO3− ion binds 1H+ ion. Therefore, the amount of Tris solution required to cause the same increase in pH level is less than that of equimolar bicarbonate solution. For that reason, regulating NETosis by pH with specific buffers such as THAM could be more effective than bicarbonate in managing NET-related diseases.

INVESTIGATING THE IMPLEMENTATION OF ZnO NANOPARTICLES AS A TUNABLE UV DETECTOR FOR DIFFERENT SKIN TYPES

A facile chemical reduction method was used to synthesize ZnO nanoparticles (NPs) in ethylene glycol solvent at two different calcination temperatures. As a result of variation in the calcination temperature, ZnO NPs with two different sizes were achieved. The NPs were investigated for their structural and optical characteristics using X-ray diffraction and ultraviolet (UV)–Vis spectroscopy. The synthesized ZnO NPs exhibited a hexagonal structure with sizes of 46 and 65[Formula: see text]nm. The synthesized NPs were then used to investigate dye photocatalytic behavior of products as a tunable UV detector for different skin types. The dye degradation and decolorization of methylene blue in the presence of ZnO NP, following UV radiation as a function of time, were studied at different pH levels. The optical absorption spectra were then taken every 15[Formula: see text]min for all samples. The UV–Vis spectroscopy spectra revealed that optical absorption of solution was decreased upon UV exposure as a function of time. Photocatalytic reaction indicated that the dye degradation and decolorization rate were accelerated with the increase of pH level. Therefore, a tunable UV detector for different skin types could be engineered by varying the pH level of solution to avoid human skin burning.

Monitoring pH with quality control based on Geostatistics Methodology

The water quality in a watershed can be changed significantly due to human activities. As a result, it has seen a significant drop in the quality of surface water. To get an evaluation efficiently and quickly the parameters that classify water were used statistical process control techniques. This work arose from the need for continuous monitoring of some parameters related to water in the region called high-San Francisco, at the mouth of the Para River. Thus, employed traditional control charts and a geostatistical methodology, as was the presence of autocorrelation. Preventing the occurrence of false alarms is important to note that the graph based on geostatistical method showed better performance, monitoring parameter hydrogen potential (pH) due to its efficiency, it is sensitive to small variations in the reduction or increase in pH levels.