Ml Of Water Research Articles

Is water a lubricant?: Inquiring about a dilemmatic statement in physics education

We designed an inquiry activity to investigate the question, ‘Is water a lubricant?’ Placing the same object on surfaces of three different materials, we observed the effect of adding a small amount of water on the coefficient of static friction, μs . Up to 1 ml of water was added. The results of each surface were graphed and compared with one another. In general, our findings show that the addition of water serves to increase μs up to a certain point, before decreasing it. The experiment can be easily replicated in a secondary school science lab. It presents two seemingly opposing phenomena, but they both hold because they occur within their respective boundary conditions.

Enhanced bacterial cellulose production in Gluconacetobacter xylinus by overexpression of two genes (bscC and bcsD) and a modified static culture

Bacterial cellulose (BC), a nanostructured material, is renowned for its excellent properties. However, its production by bacteria is costly due to low medium utilization and conversion rates. To enhance the yield of BC, this study aimed to increase BC yield through genetic modification, specifically by overexpressing bcsC and bcsD in Gluconacetobacter xylinus, and by developing a modified culture method to reduce medium viscosity by adding water during fermentation. As a result, BC yields of 5.4, 6.2, and 6.8 g/L were achieved from strains overexpressing genes bcsC, bcsD, and bcsCD, significantly surpassing the yield of 2.2 g/L from wild-type (WT) strains. In the modified culture, the BC yields of all four strains increased by >1 g/L with the addition of 20 mL of water during fermentation. Upon comparing the properties of BC, minimal differences were observed between the WT and pbcsC strains, as well as between the static and modified cultures. In contrast, BC produced by strains overexpressing bcsD had a denser microstructural network and exhibited demonstrated higher tensile strength and elongation-to-break. Compared to WT, BC from bcsD overexpressed strains also displayed enhanced crystallinity, higher degree of polymerization and improved thermal stability.

Rapid UV-curable preparation of durable soybean oil-based superhydrophobic anti-icing surfaces with excellent photothermal deicing property

Photothermal superhydrophobic coatings are promising for anti-icing/deicing. However, preparing such coatings from environmentally friendly and sustainable strategies is challenging. Herein, a bio-based and durable photothermal superhydrophobic coating is prepared via layer-by-layer strategy. Bio-based methacrylic acid epoxidized soybean oil oligomers are synthesized as an alternative to petroleum-based binders. Meanwhile, efficient photothermal conversion of hydrophobic particles are enabled by oxidative self-polymerization of dopamine to decorate hydrophobic silica particles grafted with hydrophobic long-chain alkanes and photo-curable methacrylic acid moieties. Ultimately, the superhydrophobic coating is achieved by spraying photothermal hydrophobic particles onto an oxygen-inhibited layer of pre-cured bio-based binder followed by thorough photocuring treatment. The coating exhibits powerful water repellency (WCA of 158.2 ± 1.6°, SA of 4.6 ± 0.8°), good robustness, chemical and UV irradiation resistance. Moreover, under NIR laser irradiation (808 nm, 1 W/cm2), the coating features excellent photothermal conversion efficiency (ΔT of 41.0 °C at 30 s) and stable photothermal conversion performance. And in frigid conditions (-15 °C, ∼73 ± 5 % RH), the coating delivers rapid defrosting (few seconds) and deicing (20 μL water droplet melts in 42 s) performance under NIR irradiation of 1 W/cm2. Therefore, the as-prepared coating provides valuable insight into global anti-icing/deicing action.

The Effects of Naematelia aurantialba on the Pasting and Rheological Properties of Starch and the Research and Development of Soft Candy.

To study the effects of Naematelia aurantialba (NA) on the rheological and gelatinization properties of starch, the processing methods of NA were diversified. In this study, the gelatinization and rheological properties of corn starch (CS) and edible cassava starch (ECS) were investigated by adding NA with different mass fractions. Starch soft candy was prepared using NA, CS, and ECS as the main raw materials. Rheological studies showed that both CS-NA and ECS-NA exhibited elastic modulus (G') > viscosity modulus (G″), implying elastic behavior. G' was such that CS+1%NA > CS+5%NA > CS+3%NA > CS > CS+2%NA > CS+4%NA > ECS+4%NA > ECS+3%NA > ECS+5%NA > ECS+2%NA > ECS+1%NA > ECS. The gelatinization implied showed that after adding NA, the pasting temperature of CS-NA and ECS-NA increased by 1.33 °C and decreased by 2.46 °C, while their breakdown values decreased by 442.35 cP and 866.98 cP, respectively. Through a single-factor test and orthogonal test, the best formula of starch soft candy was as follows: 0.4 f of NA, 10 g of white granulated sugar, a mass ratio of ECS to CS of 20:1 (g:g), 0.12 g of citric acid, 1 g of red date power, and 16 mL of water. The soft candy was stable when stored for two days. This study offers a new direction for the research and development of NA starch foods.

The Comparison of Lithium Carbonate Recovered from Single Type and Unknown Mixed Type of Lithium-Ion Batteries through a Simple Way Carbonated Water Leaching

Lithium is a rare earth element, but it is important in LIB manufacturing. Spent LIBs is a potential source of lithium. The research aim was to recover lithium from spent LiNCA and mixed LIBthrough selective leaching using carbonated water. The spent cathode and anode were separated by dismantling and dissolving using NaOH and hot water. The spent cathode was reduced by mixing with 20% spent anode and heating at temperature of 650 oC for 6 hours. The reduced cathodes of 25 g were mixed with 250 ml of water and flowed by 2 L/minute of CO2 gas for 150 minutes at ambient temperature. The residue was separated from filtrate. The reduced cathode and residue were examined by XRD and FTIR, while filtrate was heated for evaporating solvent to obtain precipitated Li2CO3. Theprecipitated Li2CO3 was 0,151 g/g of LiNCA and 0,034 g/g of mixed spent cathode. The characteristicsof Li2CO3 recovered from spent LiNCA closed to pure Li2CO3 even above the commercial Li2CO3 and met the requirements as an active precursor material for manufacturing LIB cathodes. Meanwhile Li2CO3 recovered from spent mixed cathode had some impurities and was needed further purification process.

Extraction of biodiesel from pomelo peel and investigation of its efficiency as a lubricant in water-based drilling fluid

Abstract Reducing friction between drill string and wellbore wall is one of the key functions of drilling fluid which may result from tight holes, key seats, differential sticking, or cutting build up along the drill string. However due to growing environmental concerns, biodegradable lubricants which are also cost-efficient are appreciated and mandated in many countries. This study discusses the performance analysis of biodegradable biodiesel produced from pomelo peels and Petroleum-based lube oil as drilling fluid lubricants. The test samples comprise 700 mL of water + 10 % bentonite + 3 % barite + 0.25 % CaCO3 + 0.25 % KOH + 1 % CMC + lubricant. Two sets of lubricants were utilized to prepare 10 samples of drilling fluid, one set with petroleum-based lubricant and other with biodiesel. Essential oil was extracted from pomelo peel with the help of the Clevenger apparatus. The oil was then converted to biodiesel through the process of transesterification. Biodiesel properties were tested for the ASTM standards. Both sets of drilling fluid samples were tested for their rheological, filtration and lubricating properties and from the results obtained it can be concluded that both type of lubricating agents have almost negligible impact on rheological and filtration loss properties. However, the lubricity coefficient values drastically decreased as we increased the lubricant content, which is an indication that biodiesel extracted from pomelo peel acts as a better lubricant. The values of the lubricity coefficient for biodiesel based drilling fluid also fell well within the advised range (<0.30). We can therefore draw the conclusion that biodiesel made from pomelo peel can replace petroleum-based lubricants while also lowering the environmental concerns related to lubricants.

Intravenous versus intramuscular oxytocin injection for preventing uterine atonic primary postpartum haemorrhage in third stage of labour: A double-blind randomised controlled trial.

To compare the efficacy and safety of intravenous and intramuscular oxytocin in preventing atonic primary postpartum haemorrhage in the third stage of labour. A double-blind randomised clinical study on consenting women without risk factors for primary postpartum haemorrhage in labour at term. Two hundred and thirty-two women were randomly allotted into intravenous (n = 115) and intramuscular (n = 117) oxytocin groups in the active management of the third stage of labour. All participants received 10 IU of oxytocin, either IV or IM, and 1 ml of water for injection as a placebo via a route alternate to that of administration of oxytocin within 1 min of the baby's delivery. The primary outcome measures were mean postpartum blood loss and haematocrit change. Trial Registration No.: PACTR201902721929705. The baseline socio-demographic and clinical characteristics were similar between the two groups (p > 0.05). There was no statistically significant difference between the two groups with regards to the mean postpartum blood loss (254.17 ± 34.85 ml versus 249.4 ± 39.88 ml; p = 0.210), haematocrit change (2.4 (0.8%) versus 2.1 (0.6%); p = 0.412) or adverse effects (p > 0.05). However, the use of additional uterotonics was significantly higher in the intravenous group (25 (21.73%) versus 17 (14.53%); p = 0.032). Although oxytocin in both study groups showed similar efficacy in terms of preventing atonic primary postpartum haemorrhage, participants who received intravenous oxytocin were more likely to require additional uterotonics to reduce their likelihood of having an atonic primary postpartum haemorrhage. However, both routes have similar side effect profiles.

Effects of pollution of saline soils with oil and oil products on soil physical properties

In the article, pollution of saline soils with oil and oil products, physical and water-physical properties depending on the level of salinity are studied. As a result of the research, it is scientifically based that the increase in the level of contamination of the soil is subject to the decrease in water permeability, and the decrease in the level of pollution is subject to the law of the increase in water permeability. In the article, weakly, moderately, strongly and very strongly contaminated soils with oil were studied. According to the results, it was determined that the water permeability of the soil was observed in 25, 45, 45, 37, 5, 3, 2 minutes, and it carried 75, 26, 44, 45, 540, 1050, 1200 ml of water, respectively, for 90 minutes. The amount of water transfer compared to the control soil for 90 minutes was less in 1%, 2%, 5% contaminated soils, and very high in 15%, 25% and 37.5% contaminated soils. The increase in the level of pollution is explained by the deterioration of water permeability and moisture retention. Also, due to the fact that oil is a viscous organic pollutant, the changes of 0.25, 0.5, 1, 3, 5, 7, 10 mm microaggregates, which are important for soil fertility, as a result of pollution, and changes in the amount of these microaggregates were also determined. It was found that the soils around the South Mirshodi oil field were previously contaminated and the amount of microaggregates smaller than 0.25 mm, 0.25 mm, 1 mm, 2 mm and 3 mm in the irrigated soils increased as the distance from the source of contamination increased. This is explained by the decrease in the concentration of oil in the soil. The amount of 5 mm, 7 mm and 10 mm aggregates has decreased. A similar situation was observed around the Kumkurgan oil base. The effect of petroleum hydrocarbons is more noticeable in microaggregates with a diameter of 10 mm.

Characterization and Effect of Processing on Parvalbumin Content in Indonesian Shortfin Eel (Anguilla Bicolor-bicolor)

Indonesian shortfin eel (Anguilla bicolor bicolor) is a high economic value fish and a high nutritional content. However, their utilization can be limited because of hypersensitivity cases in individuals allergic to fish. This study aimed to determine the characteristics of the fish major allergenic protein, parvalbumin in different parts of the eel fillet and the effects of boiling technique on the content of this protein. The samples were boiled with 100 mL of water in an Erlenmeyer flask at 95°C for 10 min. The eel fillet was divided into three parts: the front, middle, and rear part of the body. Protein profiles from each part were identified using sodium dodecyl sulfate-polyacrylamide gel electrophoresis and Bradford assays. Parvalbumin was further purified by ammonium sulfate precipitation. The concentration of protein in the different parts of the eel was not significantly different, whereas the processing treatments (meat with water (F1 extract) and meat without water (F2 extract)) affected protein concentration. Eel meat contained proteins with molecular weights ranging from 10 to 186 kDa. Parvalbumins are highly water-soluble, as their content was reduced in the fillet, but were observed at a high concentration in the water after boiling. Parvalbumins of eel were purified by ammonium sulfate 70-90% with high purity. Interestingly, two different bands were observed in SDS-PAGE, suggesting the presence of a protein variant. The molecular weight of parvalbumin obtained from purification ranged from 10 to 11 kDa, similar to that of other fish.

The Growth of Rice Plants on Combination of Liquid Organic Fertilizer Based of the Water Hyacinth

Aims: This study aims to obtain a combination of liquid organic fertilizer (LOF) concentrations of palm wine and water hyacinth on the growth of rice plants.
 Study Design: This research used a randomized block design with thri (3 replications).
 Place and Duration of Study: This research was conducted in Baolan District, Tolitoli Regency, Central Sulawesi Province with an altitude of 20 meters above sea level (MSL) from September 2022 to January 2023.
 Methodology: consisting of six treatments, namely Ao = control, A1 = 80 ml LOF of water hyacinth + 20 ml LOF of palm wine + 900 ml of water, A2 = 70 ml LOF of water hyacinth + 30 ml palm wine + 900 ml water, A3 = 50 ml water hyacinth + 50 ml palm wine + 900 ml water, A4 = 40 ml water hyacinth +60 ml palm wine + 900 ml water, A 5 = 30 ml water hyacinth + 70 ml of palm wine + 900 ml of water. Each treatment was applied to the pot as media and each pot was planted with 1 seed.
 Results: The results of the study was shown that the combination of water hyacinth and palm wine had a significant effect on plant height, number of tillers, panicle length and grain weight per panicle.
 Conclusion: Application of liquid organic fertilizer with a combination of water hyacinth and palm wine can increase rice plant growth, increase the number of tillers, panicle length and seed weight per panicle.

Experimental Investigation of the Performance of a Household Refrigerator Using Phase Change Material

A household refrigerator represents an essential device for all houses nowadays. The electric energy consumed by the refrigerator and the fluctuation of the temperature inside the fresh food cabin is the main two problems affecting its performance. Incorporating phase change material (PCM) inside the refrigerator is one of the solutions for the previous mentioned problems. In the present study, a water PCM is added to the cabinet of 220-litters double door refrigerator. The PCM (0.5 ml of water) is added at three different locations, touch the front of the evaporator part inside the cabin, touch the rear of the evaporator part in the cabin, and far away from the evaporator part inside the cabin. The location of the PCM determines how much energy is released and stored from the evaporator. The use of phase change material (PCM) touch to the evaporator increases the rate of heat transfer due to the conduction method being used throughout the whole heat transfer process from the evaporator to the phase changematerial (PCM), which raises the refrigeration system's COP (coefficient of performance). The experimental test period is 24 hours for each day. Firstly, the refrigerator is tested without using PCM, and the power consumption, the temperatures at different points for the refrigerator, suction pressure, discharge pressure, the ambient temperature, and the time on period and time off period of the compressor are measured. Secondly, for same testing period all previous parameters are measured with using PCMat different locations inside the refrigerator. The results show that, adding the PCM (water) behind the evaporator led to increase the COP by 21.97%, increase the compressor off time by 73 minutes, reduction in power consumption of 14.4%, decrease of exergy losses of the system by 8% and temperature fluctuation reduced inside the fresh food cabin, that enhance the quality of stored food. Adding the PCM front the evaporator improve the previous parameters but less than that of the first case. The third location, adding the PCM far away from the evaporator has no improvement on the refrigerator's performance.

Taro (Colocasia esculenta) and sea grapes (Caulerpa lentillifera) as potential materials for making bioplastic

Plastic pollution has become a global concern, and the country Philippines is one of the plastic waste generators worldwide. The accumulation of non-recyclable, single-use plastics threatens marine life and contributes to global warming. This study aimed to contribute to reducing plastic pollution and provide insights into sustainable alternatives to single-use plastics. Hence, this research explores the potential of bioplastics as an alternative to traditional plastics. Specifically, this study primarily focused on developing bioplastics using taro and sea grapes as raw materials to provide an eco-friendly alternative to traditional plastics. The researcher aimed to investigate three different concentrations of bioplastic made from taro and sea grapes and evaluate their tensile strength, water absorbency, and biodegradability. The findings revealed that the second sample, consisting of 20 grams of taro starch, 15 mL of sea grape extract, two tablespoons of vinegar, 7.5 mL of glycerine, and 40 mL of water, exhibits the best outcome regarding its tensile strength, water absorbency, and biodegradability. Based on the results, the researchers concluded that bioplastics derived from taro starch and sea grape extract possess promising properties. The study highlights the importance of optimizing the concentration of raw materials to achieve desired characteristics in bioplastic production.

The Efficiency of κ-Carrageenan-Chitosan-PVA-MWCNTs Membranes in Removing Methylene Blue, Rhodamine B, Bromocresol Purple, and Murexid from Water

The electrocoagulation method has been proven to be highly effective in removing metal ions from water, with a removal efficiency of over 97%. However, in terms of removing organic pollutants such as synthetic dyes, the efficiency of electrocoagulation is still relatively low. A hybrid approach combining electrocoagulation with membrane filtration has been proposed to enhance the removal of organic contaminants. Eco-friendly membranes made from renewable natural polymers like carrageenan and chitosan, reinforced with synthetic polymers such as polyvinyl alcohol and carbon nanotubes, have shown to be promising for this application. In this study, membranes with varying chitosan/carrageenan ratios of 0.2, 0.33, 0.5, and 0.71 (g/g) were used to remove synthetic dyes, including methylene blue, rhodamine B, bromocresol purple, and murexid, at a concentration of 200 ppm from 8.5 ml of water. From the SEM images, the four membranes have almost the same surface and cross-section morphology. The results showed that the membrane with a chitosan/carrageenan ratio of 0.71 exhibited the highest removal efficiency for all synthetic dyes. The parameter affecting the membrane’s removal efficiency is the interaction between the membrane and synthetic dyes. Murexid, an anionic dye, achieved a 100% removal efficiency, surpassing cationic dyes such as rhodamine B and methylene blue. Besides interactions, the dye’s molecular size determines the removal’s efficiency. The molecular size of rhodamine B is larger than that of methylene blue, and the removal efficiency of rhodamine B (98.4%) is greater than methylene blue (91%). Bromocresol purple is almost the same size as rhodamine B but not ionic because it has the lowest removal efficiency of 34.55%.

The challenges of developing a textile-based device for recognizing swallowing movements during different swallowing tasks

Swallowing difficulty, also known as dysphagia, is a fairly common symptom that may lead to malnutrition, dehydration, pulmonary complications, and a reduced quality of life. Currently, a swallowing evaluation requires a hospital environment, skilled personnel, and expensive devices. Thus, it is important to develop a successful method for evaluating swallowing in an everyday environment. This study developed a textile-based solution that resembles a neck gaiter. Wireless accelerometer and gyroscope sensors embedded inside the gaiter were used to detect swallowing movements. The recognition of swallows was achieved through cervical auscultation and video footage, and this data was subsequently compared with the information obtained from wireless accelerometer and gyroscope sensors. Based on the measurement results for 17 adults without dysphagia, the developed neck gaiter can identify individual swallows of 5 sips of water (with a 97 % identification success rate) and consecutive swallows of 100 ml of water (98 % identification success rate). However, we were not able to recognize swallowing movements from speaking, chewing and head movements. Future research is now needed to develop a prototype to differentiate swallowing movements from other movements, such as chewing and speaking.

Enterococcus Species and Their Antimicrobial Resistance in an Urban Watershed Affected by Different Anthropogenic Sources

Different anthropogenic sources can have a significant influence on bacterial populations and their antimicrobial activities. In this study, the impact of anthropogenic activities on Enterococcus species was studied in an urban watershed in southern California affected by concentrated animal feeding operations (CAFOs), recreational activities, wastewater treatment plants (WWTPs), urban runoff, and control sites. Water samples were collected quarterly for two years for the enumeration of Enterococcus species based on the Enterolert most probable-number (MPN) assay. Concentrations of enterococci were higher in the sediment compared to surface water (4.5 × 106 CFU/g of sediment vs. 2.3 × 105 MPN/100 mL of water). The species diversity was dominated by E. mundtii (32%), E. faecalis (27%), and E. faecium (25%). E. faecium exhibited the highest antibiotic-resistant phenotype. Resistances were mostly to ciprofloxacin, erythromycin, and tetracycline. Tetracycline and erythromycin resistance genes, encoded by tet (C, K, O, S) and ermB, respectively, were more common in isolates from sediment (42.9%) compared to water (12.7%). E. mundtii was sensitive to ampicillin, chloramphenicol, gentamicin, and high levels of vancomycin. A significant percentage of E. faecalis were also resistant to these antibiotics. E. faecium and E. faecalis exhibited resistance to multiple antibiotics. Our data suggest that resistant Enterococcus species within the watershed might provide some useful data to determine pollutant types and sources in that watershed. Therefore, the widespread occurrence and abundance of E. faecium and E. faecalis, and their resistance genes associated with multiple antibiotics may potentially pose risks to the local populations exposed to these water sources during recreational activities.

Influence of firefighting fluorosynthetic film forming foam on soil microbocenosis

Per- and polyfluoroalkyl substances (PFASs) are a group of over 5000 different chemicals that are used in a wide range of industrial applications and consumer products. Perfluoroalkyl substances have unique properties, such as high chemical stability and surface activity, which leads to their widespread use in medicine, science and everyday life. Aqueous film forming foams (AFFFs) are complex proprietary formulations that contain percent levels of PFASs as well as solvents and hydrocarbon surfactants which, when combined, afford AFFF the functionality required for its purpose. Firefighting foams, such as AFFF, are used primarily to control fires involving flammable liquids such as fuel and oil. AFFF suppresses fire by producing a film over the fuel/oil fire that effectively starves the fire of oxygen. The carbon-fluorine bond makes these compounds extremely strong and stable. This chemical and thermal stability allows these substances to persist in the environment without breaking down. While biological effects of single PFAS have been studied, the effects of PFAS-containing mixtures, such as AFFF, are unknown. The environmental effects of firefighting foam pollutants are generally considered in terms of their toxicity and their biodegradability. Firefighting foams have been found to have a negative impact on the environment (e.g. can remove oxygen from aquatic environment in turn killing aquatic fauna). The effect of PFAS on the microorganisms is not sufficiently studied. To date, there are few studies on the structure and dynamics of microbes in the presence of per- and polyfluoroalkyl substances. Moreover, the results are contradictory. In this regard, it is important to study the impact of various PFAS chemicals on the microorganisms. The article presents the results of the effect study of a fluorosynthetic film forming foam, the main component of which is perfluorinated organic acid, on soil microorganisms, namely ammonifiers, oligonitrophils and nitrogen-fixing microorganisms, yeasts and molds, actinobacteria, and cellulose-degrading bacteria. It was accomplished by plating a sample of the soil that has been serially diluted in water and enumeration of colony forming units (CFU) per gram of soil. The number of soil microorganisms was counted two weeks and three months after contamination with a fluorosynthetic film forming foam. The control sample was unpolluted soil. The sample of soil (1.0 g) was mixed and suspended with a 10 ml of water in a tube for isolation and enumeration of microorganisms. The sample was shaken vigorously to separate organisms from the colloidal material surrounding soil particles. Obtained suspension was serially diluted from 10-2 to 10-6. Aliquot of each dilution was plated onto suitable agar medium. Meat-peptone agar, wort agar, starch-ammonia agar, ashby's agar and hutchinson's agar were used to isolate different groups of microorganisms from gray forest soil and to study the effect of film forming foam on them. The plates were incubated at 28 °C for 3–14 days and the results are expressed as CFU per gram of soil. Colonies of bacteria on meat-peptone agar and ashby's medium were counted after 3–4 days, yeasts and fungi on wort agar after 4–5 days and actinobacteria on starch-ammonia medium after 7–10 days. The number of colonies of cellulose-degrading microorganisms was counted after 14 days cultivation. Firefighting fluorosynthetic film forming foam led to the soil microbial community restructuring and a microbial diversity decrease. The study revealed a decrease the number of different groups of soil microorganisms two weeks after the pollution with the firefighting fluorosynthetic film forming foam, in particular ammonifiers by 2 times compared to the control, nitrogen-fixing microorganisms by 2.7 times, actinobacteria by 4.7 times, yeasts and fungi by 2.8 times. Three months after soil contamination with AFFF the number of nitrogen-fixing microorganisms, actinobacteria, yeasts and fungi increased by 1.85, 1.2 and 2.6 times compared to the control respectively. The number of ammonifiers and cellulose-degrading microorganisms decreased by 1.7 and 5.0 times compared to the control respectively.

Sensory Profiling of Indonesian White Tea Using Quantitative Descriptive Analysis

Silver needle is a common type of white tea in Indonesia. The silver needle is produced from unbloomed pekoe, is pointed, slightly hairy, and silver in color. Quantitative descriptive analysis is a sensory evaluation method that relies on trained panelists' abilities in the experiment. The purpose of this study is to create a sensory profile of white tea from Indonesia using the QDA method. Five tea samples registered to the Indonesian National Agency for Drug and Food Control (Brand Gamboeng, Ennie 1, and Cap Pucuk from the West Java, Teh Dandang from Central Java, and Brand Heizl from East Java) were evaluated by trained panelists with extensive experience who had passed selection and training processes. Water was used as the neutralizer and crackers as the carrier. Three grams of each sample were brewed at 98°C with 150 mL of water for 7 min. Each panelist described the attribute, determined the reference, and evaluated all samples on a 15-cm scale. The results of the focus group discussion has obtained 12 lexicon sensory attributes, namely: yellow-brown, burned aroma, floral aroma, dry aroma, woody aroma, green aroma, burned flavor, green flavor, fermented flavor, floral flavor, bitter taste, astringent aftertaste, and bitter aftertaste. The results also showed that the "Heizl" white tea had the following sensory characteristics: yellow-brown, burned aroma, burned flavor, fermented flavor, bitter taste, bitter aftertaste, and astringent aftertaste. Moreover, the "Dandang" white tea had the following attributes: dry aroma, floral aroma, woody aroma, green aroma, green flavor, and floral flavor.

REFRIGERAÇÃO TERMOELÉTRICA: EXPLORANDO O EFEITO PELTIER EM UM SISTEMA CASEIRO DE REFRIGERAÇÃO

Semiconductors are raw material for the production of integrated circuits and chips, playing a fundamental role in the evolution of modern tech¬nologies. However, other effects can be explored, as is the case of Peltier Effect cells and tablets which, when subjected to a potential difference at their terminals, have the ability to absorb heat on one of their faces, lowering its temperature, while dispersing it on the opposite face, which has its temperature increased. This finding allowed that this thermoelectrical equipment could be used in cooling processes of small volumes, combined with other devices such as heat sinks and small fans, essential to improve the performance of the set when placed together. The availability and easy access to these components, as well as the construction of a small controlled and thermally isolated environment, allowed the develop¬ment of a cooling system project that uses the thermoelectric phenomena of the Peltier Effect tablets. The refrigerator made strengthens the application of tablets in this regard, exposing thermal amplitudes of 14.8°C in relation to the environ¬ment, and showing effectiveness in reducing the temperature by up to 11°C in a volume of 250 ml of water inserted in it.

Comparative study of the action of dynamized forms of melatonin and lissotriton

The effect of dynamized forms of Melatonin 6 cH and Lissotriton 6 cH were studied in comparison. Melatonin and Lissotriton are universal stimulantors of regeneration. In animals, melatonin is a hormone regulating circadian rhythms, seasonal reproduction, and many other physiological functions. Lissotriton is the recrystallized and dinamized form of tissue of Lissotriton vulgares. Materials and methods. White laboratory one years old mice of the vivarium of KSMY received a dynamizing form of Melatonin 6 cH and Lissotriton 6 cH at a dose of 5 drops per 20 ml of water for 14 days. The 3-d group was a control. Results. The study showed the best structure of wool, hair and activity of rodents who took Melatonin 6 cH and Lissotriton 6 cH. The coat of the animal becomes bright, healthy and thick, many follicles are visible on histological slides of epidermis and derma (x80). The microscopic examination showed perfect adhering of the cuticle to the cortical layer. Also the forced swimming method confirmed that the dynamic form of Melatonin and Lissotriton increased the adaptability of the animals. Swimming time was 2.5 times longer (Melatonin) and 4 times longer (Lissotriton) compared to control groups.

Ultrasound evaluation of gastric emptying time of standardized high-calorie liquid meals in healthy adults: A double-blind cross-over randomized study

Commercially available high-calorie drinks containing fat and protein can be used as dietary supplements in surgical patients. According to preoperative fasting guidelines, high-calorie drinks are non-clear fluids and should not be consumed 6h before elective procedures. The aim of this study was to evaluate the gastric emptying time of commercially available high-calorie drink formulations in healthy adults using gastric ultrasound. 25 healthy adult volunteers were included in this double-blind, cross-over prospective study. On three study sessions, fasted volunteers ingested one of the three study products: a solution of 75g of glucose in 200ml of water, a fat-free liquid meal, and a nutritionally complete liquid meal with equal volume and energy content. Gastric ultrasound examinations were performed to evaluate the gastric contents qualitatively and the volume of the gastric contents was calculated from the cross-sectional area of the gastric antrum measured in right lateral position by using a validated model. Repeated gastric ultrasounds were performed at baseline and half-hourly after ingesting the products in supine and right lateral position until the criteria for an empty stomach were met. The glucose solution and the standard fat-free high-calorie drink with the same caloric content had a median gastric emptying time of 150min. The nutritionally complete liquid meal had a median gastric emptying time of 180min. Gastric emptying was complete in all participants before 6h had elapsed since ingesting the study products. High calorie liquid meals have a gastric emptying time longer than the recommended fasting time for clear fluids, but shorter than the recommended fasting time for solids in healthy adults.