Storage Time Research Articles

Design and research of a novel type of arc fin for heat transfer enhancement in hot water oil-displacement system

Phase change thermal storage system utilizes solar energy to provide continuous heat and electricity for offshore platforms in the petroleum industry. However, the low thermal conductivity of the heat storage medium (phase change material) in the system limits the overall heat transfer efficiency. This study focuses on the design of a novel longitudinal arc fin to enhance heat transfer in the storage system. A comparison is made between the influence of the rectangular fin and the novel longitudinal arc fin structure, as well as the impact of the fin number on the heat storage performance of the heat storage unit. A numerical model is constructed and used to analyze the grid and time step in the numerical process. The resulting data is further validated through experimental comparison. The study also examines the impact of fin structure and fin number on the internal convection and temperature of this phase change heat storage unit, comparing thermal performance parameters such as heat storage time, heat storage rate, temperature response, and overall heat storage. Findings indicate that, under constant overall fin size, increasing fin number significantly enhances the internal temperature of this unit. Additionally, changing the shape of fins from rectangular to arc-shaped results in decreased heat storage performance. Specifically, when compared to the initial rectangular structure, the melting time of 8 arc fins and 10 arc fins decreased by 30.70% and 40.65%, the mean temperature response increased by 45.01% and 67.70%, and the mean rate of heat storage increased by 45.35% and 69.23%. Therefore, increasing the number of arc-shaped fins, while maintaining the same fin volume, substantially improves the heat storage properties of the unit.

Estimation of the shelf life of sweetened soft drinks based on microbiological and sensory analysis

In the present investigation, the shelf life of sweetened beverages was investigated through microbiological and sensory analyses. An experimental design was employed, which included the variable of storage time. This allowed for the identification of significant differences in the organoleptic and microbiological characteristics of the beverages. Samples of the beverages were taken during their processing and evaluated over time, especially during the pasteurization process at 85°C for 120 seconds. Laboratory analyses focused on microbiological tests, sensory studies, and assessments of the processed product's quality. The microbiological results remained within the limits established by INEN standards, with counts of mesophilic aerobes < 100 CFU/cm3, yeasts and molds < 50 CFU/cm3, total coliforms < 3 MPN/cm3, and fecal coliforms < 3 MPN/cm3. Regarding sensory analysis, it was found that the beverages had a characteristic aroma, a slightly yellow color, and a characteristic citrus flavor, making them highly acceptable to consumers. Furthermore, the shelf life of the beverages was determined through accelerated aging at 32°C, resulting in a shelf life of 2 months. These findings supported the conclusion that the beverages could be stored for 6 months at room temperature, as indicated in another study that employed a similar methodology and evaluated properties such as color, aroma, and flavor. Keywords: Analysis, mesophilic aerobes, fecal coliforms, yeasts and fungi4 , shelf life

Comparative evaluation of the dimensional accuracy of two commercially available extended pour alginates and a conventional alginate impression material at various time intervals – An in vitro study

Because of its acceptable accuracy, affordable price, accessible availability, and simplicity of handling, alginate impression materials continue to be a crucial component of dental practice despite many developments.The purpose of this study was to evaluate and compare the dimensional accuracy of two commercially available extended pour alginates (Cavex ColorChange and Algeniux) and a conventional alginate impression material (Zelgan) at different time intervals. On a maxillary model (Columbia Dentoform, Long Island City, N.Y.) the canines and the first molars were replaced with metal dies. This was selected as the master model. A ‘+’ mark was inscribed on these metal dies to serve as a reference for measurements. A self-cure acrylic resin custom tray was fabricated such that it was positioned over the model in the same spatial relationship with equal amount of space between the tray and model every time an impression was made. A total of 180 impressions were made of the master model, 15 impressions with each material at four different time intervals; immediate, 30 minutes, 48 hours (2 days) and 120 hours (5 days) to obtain gypsum cast. Manufacturer recommended water/powder ratios and storage conditions were followed in the process. Following the designated storage time interval, the casts were poured in minimum expansion Type IV dental stone. Measurements were done with a coordinate measuring machine after 7 days when the casts were completely dry. To evaluate and compare the dimensional accuracy of materials across various time points, for each group, the mean and standard deviation were estimated and subjected to statistical analysis. Two Way Repeated Measure Analysis of Variance (ANOVA) was performed to determine if the dimensions differed significantly across groups with time. The pair wise analysis for materials and time points was performed using Tukey’s post-hoc test. The p value was taken as significant when less than 0.05.Across different time points, a minimum % change was observed at immediate time point, which gradually increased at 30 minutes and at 48 hour, but at 120 hour the % change was maximum for all dimensions. Among three groups, Cavex ColorChange material showed minimum % change across time points, whereas Zelgan group showed maximum % change across all dimensions. All the paired differences were statistically insignificant (p > 0.05) for Algeniux and Cavex ColorChange group. But for Zelgan group, the difference between all the pairs of time points were statistically significant (p < 0.05), except for the pair immediate vs. 30 minutes. These results suggest that Zelgan material showed significant changes after 30 min for all the dimensions.: The results revealed that both the extended pour alginates Cavex ColorChange and Algeniux produced dimensionally accurate casts at all time intervals while the conventional alginate, Zelgan was accurate only at immediate and 30-minute time interval. It was also observed that, among the 4-time intervals investigated, most accurate casts were obtained when the impressions were poured immediately.

Improved production strain maintenance technique for Burkholderia mallei 5584 (Master seed) used for glander diagnostic agent production

One of the aspects important for strain collection maintenance is the optimization of existing methods and development of new techniques for microbial strain preservation, that is why the improvement of previously developed methods for authentic strain preservation is an urgent task. The article provides information on the maintenance of Burkholderia mallei 5584 (Master seed) using previously developed technique, which was supplemented with new stages in accordance with modern requirements for strain collections of highly dangerous disease agents. The previous strain maintenance technique involved its storage in its native state, which facilitated accumulation of genetic mutations and, ultimately modification of bacterial cell properties. To extend the storage time of this strain and to ensure the stability of its biological properties, the freeze-drying method was used. Skimmed milk was used as a cryoprotectant. Freeze-drying was performed under selected conditions. This technique allows for the strain sub-culturing on sensitive models once every 5 years, which is more expedient and safe from an economic and biological point of view. For safe handling of Burkholderia mallei 5584 production strain, an inactivation technique using gamma rays at 30 kGy was developed, which allowed to achieve microbial suspension sterility and preserve the bacterial cell structure. When comparing the previously developed and supplemented techniques, it was found that the improved technique of Burkholderia mallei 5584 (Master seed) maintenance makes it possible to avoid the loss of its biological properties needed for the production of high-quality laboratory diagnostic agents used for timely disease detection in susceptible animals by diagnostic tests.

In platelet single donor apheresis, platelet factor 4 levels correlated with donor's age and decreased during storage.

The human population is ageing worldwide. The World Health Organization estimated that the world's population of people aged60years and older will increase to at least 30%, coinciding with a growing frequency of cognitive and cardiovascular disease. Recently, in preclinical studies platelet Factor 4 (PF4) was presented as a pro-cognitive factor. This molecule is released by platelets in the circulation and could be present in blood products destined for transfusion. We wondered if PF4 levels are correlated to the age of the blood donor or to the storage time of platelet concentrates (PCs) intended for transfusion? We observed higher levels of PF4 in PCs from elderly donors compared to younger donors, while PC storage time did not determine PF4 levels expression.

Influence of Subsurface Critical Zone Structure on Hydrological Partitioning in Mountainous Headwater Catchments

AbstractHeadwater catchments play a vital role in regional water supply and ecohydrology, and a quantitative understanding of the hydrological partitioning in these catchments is critically needed, particularly under a changing climate. Recent studies have highlighted the importance of subsurface critical zone (CZ) structure in modulating the partitioning of precipitation in mountainous catchments; however, few existing studies have explicitly taken into account the 3D subsurface CZ structure. In this study, we designed realistic synthetic catchment models based on seismic velocity‐estimated 3D subsurface CZ structures. Integrated hydrologic modeling is then used to study the effects of the shape of the weathered bedrock and the associated storage capacity on various hydrologic fluxes and storages in mountainous headwater catchments. Numerical results show that the weathered bedrock affects not only the magnitude but also the peak time of both streamflow and subsurface dynamic storage.

Levels of Phthalate Acid Esters in Carbonated Soft Drinks Bottled in Polyethylene Terephthalate (PET) Bottles Kept under Various Storage Conditions in Mwanza City, Tanzania

Background: Carbonated soft drinks (CSD), packaged in PET (polyethylene terephthalate) bottles, are among the most widely consumed non-alcoholic beverage globally. People of all ages enjoy CSDs for their flavour, mouthfeel, crispness, freshness, and capacity to both quench thirst and provide mental refreshment. Terephthalic acid, ethylene glycol, and other additives such as phthalates are the materials used to make these PET bottles. Several studies have demonstrated that phthalates may migrate into packaged goods and, when consumed, can cause several ill-health conditions to humans. Type II diabetes, obesity, asthma, male and female reproductive disorders, tumours (including breast cancer), pituitary, hypothalamic, and peripheral hormone disorders, behavioral issues, and neurodevelopmental disorders are among the health issues reported to be associated with phthalates. Objective: This study aimed to ascertain the presence and concentration of phthalates in PET bottled carbonated soft drinks produced in Mwanza City, and to examine the effects of various storage conditions on the migration of these contaminants into the product. Methods: Liquid-liquid extraction, clean-up techniques, and chromatographic analysis were used as the methods of determination to identify and quantify the specific phthalates compounds. Results: The findings demonstrated that after being stored outdoors for four to six months, the migration, especially for dibutyl phthalate (DBP) and di [2-ethylhexyl] phthalate (DEHP), became more apparent. After two, four, and six months of indoor storage, there was no appreciable change in the mean concentrations of DMP (dimethyl phthalate), DEP (diethyl phthalate), DBP (dibutyl phthalate), and DEHP for either brand in this study. Compared to indoor storage, the DBP and DEHP migration increased by up to 24-fold when the two brands were kept outdoors for four and six months. Thus, the safety and quality of carbonated soft drinks were seriously compromised by the phthalate compounds from the PET bottles that these companies were using. Conclusion: The study's conclusions show that PET packaging, which is influenced by the bottle manufacturing process and raw material formulations for packages of the studied CSDs, are responsible for the migration of phthalates into the products. The storage conditions and time are established to be the primary causes of phthalates migration in bottled carbonated soft drinks. Though the migration figures in this study are lower than those of the other studies from different locations that were compared, it is important to remember that these compounds may interfere with hormones even in small quantities.

Normothermic machine perfusion for liver transplantation: current state and future directions.

The number of patients on the liver transplant waitlist continues to grow and far exceeds the number of livers available for transplantation. Normothermic machine perfusion (NMP) allows for ex-vivo perfusion under physiologic conditions with the potential to significantly increase organ yield and expand the donor pool. Several studies have found increased utilization of donation after cardiac death and extended criteria brain-dead donor livers with implementation of NMP, largely due to the ability to perform viability testing during machine perfusion. Recently, proposed viability criteria include lactate clearance, maintenance of perfusate pH more than 7.2, ALT less than 6000 u/l, evidence of glucose metabolism and bile production. Optimization of liver grafts during NMP is an active area of research and includes interventions for defatting steatotic livers, preventing ischemic cholangiopathy and rejection, and minimizing ischemia reperfusion injury. NMP has resulted in increased organ utilization from marginal donors with acceptable outcomes. The added flexibility of prolonged organ storage times has the potential to improve time constraints and transplant logistics. Further research to determine ideal viability criteria and investigate ways to optimize marginal and otherwise nontransplantable liver grafts during NMP is warranted.

Investigation of phonon lifetimes and magnon–phonon coupling in YIG/GGG hybrid magnonic systems in the diffraction limited regime

Quantum memories facilitate the storage and retrieval of quantum information for on-chip and long-distance quantum communications. Thus, they play a critical role in quantum information processing and have diverse applications ranging from aerospace to medical imaging fields. Bulk acoustic wave (BAW) phonons are attractive candidates for quantum memories because of their long lifetimes and high operating frequencies. In this study, we establish a modeling approach to design hybrid magnonic high-overtone bulk acoustic wave resonator (HBAR) structures for high-density, long-lasting quantum memories, and efficient quantum transduction devices. We illustrate the approach by investigating a hybrid magnonic system, consisting of a gadolinium iron garnet (GGG) thick film and a patterned yttrium iron garnet (YIG) thin film. The BAW phonons are excited in GGG thick film via coupling with magnons in the YIG thin film. We present theoretical and numerical analyses of the diffraction-limited BAW phonon lifetimes, modeshapes, and magnon–phonon coupling strengths in YIG/GGG planar and confocal HBAR (CHBAR) structures. We utilize Fourier beam propagation and Hankel transform eigenvalue problem methods and compare the two methods. We discuss strategies to improve the phonon lifetimes in the diffraction-limited regime, since increased lifetimes have direct implications on the storage times of quantum states for quantum memory applications. We find that ultra-high cooperativities and phonon lifetimes on the order of ∼105 and ∼10 milliseconds, respectively, could be achieved using a CHBAR structure with 10μm YIG lateral area. Additionally, high integration density of on-chip memory or transduction centers is naturally desired for high-density memory or transduction devices. The proposed CHBAR structure will offer more than 100-fold improvement of integration density relative to a recently demonstrated YIG/GGG device. Our results will have direct applicability for devices operating in the cryogenic or milliKelvin regimes. For example, our study will inform the design of HBAR devices that could couple with superconducting qubits for promising quantum information platforms.

Platelet activation and blood extracellular vesicles: The influence of venepuncture and short blood storage

Extracellular vesicles (EVs) as membrane-bound particles released by various cells are potential tools for diagnosis and treatment. Blood cells, particularly platelets, are the source of circulating EVs. MaterialEVs were enriched with gradient ultracentrifugation and measured by nanoparticle tracking assay. A flow cytometric multiplex assay was used for cellular source determination. Activation of platelets was measured as a percentage of CD62p+/CD61+ platelets and correlated with the concentration and size of released EVs. ResultsIn general there was no statistically significant correlation between EVs` concentration and degree of platelet activation. EVs from different cellular sources were detected. Comparing different needle thicknesses, there was a decrease in the EVs concentration for the 16G needle versus the 21G needle, but no difference was observed for EVs` size and phenotype or platelets activation. During blood storage, platelet activation increased, but there was no effect on the EVs` concentration, size, or phenotype. ConclusionsPreanalytical factors like needle thickness and storage time can affect the MVs' properties. Activation of platelets during blood collection or blood storage occurs; however, it is difficult to determine its effect on the physiological properties of EVs since the mechanisms of EVs` biogenesis and especially clearness are not precisely known.

Evaluation of Changes in Sensory Quality and Bacterial Community Composition of Cold-Eating Rabbit Meat Stored under Different Temperatures

In Sichuan cuisine, cold-eating rabbit meat is highly regarded for its very strong taste and historical legacy. This study is aimed at evaluating the quality and bacterial diversity of cold-eating rabbit meat during storage. Under different storage time and temperatures, cold-eating rabbit meat underwent a decrease in pH, whereas the contents of thiobarbituric acid reactive substances, total volatile basic nitrogen, and total viable count increased. Moreover, the loads of lactic acid bacteria and Staphylococcus aureus increased. Furthermore, 20 different bacterial genera were identified throughout the stages of raw meat processing and storage. Among these, Tardiphaga was the most abundant species during processing and storage. Lactobacillus was found to dominate the bacterial community associated with spoilage alterations in cold-eating rabbit meat. Thus, cold-eating rabbit meat can be safely stored at 4°C for up to 42 days. These findings offer valuable insights into the microbial processes underlying spoilage of cold-eating rabbit meat and serve as a guide for the development of strategies to prevent spoilage during processing and storage of cold-eating rabbit meat.

Assessment of the Effect of Transit Time between Harvesting and Processing on the Physicochemical Quality Parameters of Preharvest Burnt Sugarcane

Aim: This study was aimed at assessing the effect of time interval between harvesting and processing on the physical and chemical quality parameters of pre-harvest burnt sugarcane
 Study Design: An experimental research design was carried out that involve random selection of samples and sent to laboratory for analysis
 Place and Duration of Study: The study was carried out on July from 26th to 30th 2023 in Kilombero Valley located in the eastern part of Tanzania, between latitude 7 0 42'42'S and longitude 37 0 00'00'E. 
 Methodology: The NCO 376 variety of sugarcane was used, that were cut below ground level, the tops removed, stalks tightened in bundles. The sample size was 15. each sample constituted of 30 burnt sugarcane stalks samples that were randomly collected and sent to laboratory for analysis after 24 ,72 and 120 hours of storage. On every respective storage time, the samples were scratched with knife to remove external contaminants, the stalks were then milled using two roller machines to extract juice. The juice was filled and sealed in sterilized and labelled bottles ready for laboratory analysis. The laboratory analysis data collected were coded and entered in excel sheet and analysed using Statistical Package for Social Science (SPSS) version 25.
 Results: The result shows the means values for pH, brix , pol, purity and weight decreased with increase in storage time whereas the means values for dextran, yeast and Leuconostoc increased with increase storage time The results revealed that purity values were satisfactory in all storage time levels as compared to SASTA standard purity values (97.0 – 98.0% ), whereas mean values for brix and pol stored for 120 hours of storage time was not satisfactory.as compared to SASTA standard values for brix ( 18 – 23%) and pol (14 – 21%) .Dextran concentration was high as compared to South African Sugar Terminals (SAST) that maximum requirement for dextran is 150 mg/kg, dextran level as the measure of microbial deterioration was high in 72 and 120 storage hours indicating microbial contamination.
 Conclusion: Farmers and processors should be well informed about the consequence of delayed processing burned sugarcane to avoid economic loss for farmers and processors.

High-Pressure Processing of Fruit Smoothies Enriched with Dietary Fiber from Carrot Discards: Effects on the Contents and Bioaccessibilities of Carotenoids and Vitamin E.

The effects of high-pressure processing (HPP) (450 MPa/600 MPa/3 min) on the carotenoid and vitamin E contents of smoothies made from strawberry, orange juice, banana and apple, and the same smoothies enriched with dietary fiber from discarded carrots were compared. The contents and bioaccessibilities of these compounds were also evaluated over the course of 28 days at 4 °C. The application of HPP in the formulations significantly increased the contents of β-cryptoxanthin, α-carotene and β-carotene and retained the contents of lutein, zeaxanthin and vitamin E compared to untreated samples. A decreasing trend in the content of each compound was observed with an increase in storage time. The application of HPP initially led to reductions in the bioaccessibility of individual compounds. However, overall, during storage, there was an increase in bioaccessibility. This suggests that HPP influences cell structure, favoring compound release and micelle formation. HPP is a sustainable method that preserves or enhances carotenoid extractability in ready-to-drink fruit beverages. Furthermore, the incorporation of dietary fiber from carrot processing discards supports circular economy practices and enhances the health potential of the product.

Influence of storage solution, temperature, assay time and concentration on RT-qPCR nucleic acid detection for SARS-CoV-2 detection of SARS-CoV-2 by the RT-qPCR

Real-time reverse transcriptase quantitative polymerase chain reaction (RT-qPCR) is an important method for the early diagnosis of coronavirus disease 2019 (COVID-19). This study investigated the effects of storage solution, temperature and detection time on severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) nucleic acid detection by RT-qPCR. Various concentrations of SARS-CoV-2 were added to inactive and non-inactive storage solution and the viral suspensions were stored at various temperatures (room temperature, 4, −20 and −80 °C). Then, at five different detection time points, the Ct values were determined by RT-qPCR. Active and inactive storage solutions and storage temperature have a great impact on the detection of N gene of SARS-CoV-2 at different concentration corridors but have little impact on the ORF gene. The storage time has a greater impact on the N gene and ORF gene at high concentrations but has no effect on the two genes at low concentrations. In conclusion, storage temperature, storage time and storage status (inactivated, non-inactivated) have no effect on the nucleic acid detection of SARS-CoV-2 at the same concentration. For different concentrations of SARS-CoV-2, the detection of N gene is mainly affected.

Gamma irradiation and ozone application as preservation methods for longer-term storage of bee pollen

Bee pollen is a healthy product with a good nutritional profile and therapeutic properties. Its high moisture content, however, promotes the growth of bacteria, molds, and yeast during storage commonly result in product degradation. Therefore, the aim of this study is to assess the effectiveness of gamma irradiation (GI) and ozone (OZ) as bee pollen preservation methods for longer storage time, as well as whether they are influenced by pollen species. To do that, GI at a dosage of 2.5, 5.0, and 7.5 kGy was applied at a rate of 0.68 kGy/h and OZ application at a concentration of 0.01, 0.02, and 0.03 g/m3 was applied for one time for 6 h, to Egyptian clover and maize bee pollen, then stored at ambient temperature for 6 months. We then determined the total phenolic content (TPC) and antioxidant activity of treated and non-treated pollen samples at 0, 3, and 6 months of storage. Total bacteria, mold, and yeast count were also evaluated at 0, 2, 4, and 6 months. Statistical analyses revealed that, TPC, antioxidant, and microbial load of both clover and maize pollen samples were significantly (p < 0.05) affected by both treatment and storage time and their interaction. Both methods were extremely effective at preserving the antioxidant properties of pollen samples after 6 months of storage at room temperature. Furthermore, the highest concentrations of both GI and OZ applications completely protected pollen samples from mold and yeast while decreasing bacterial contamination. GI at the highest dose (7.5 KGy) was found to be more effective than other GI doses and OZ application in preserving biologically active compounds and lowering the microbial count of pollen samples for 6 months. As a result, we advise beekeepers to use GI at this dose for longer-term storage.

Creating Deep Traps in Yttrium Aluminum Garnet for Long‐Term Optical Storage and Afterglow‐Intensity‐Ratio‐Based Temperature Sensing

AbstractDeep traps are needed for electron‐trapping‐based long‐term optical storage due to its resistance to thermal erasure. Current electron trapping materials have the erasing temperatures hardly beyond 600 K, limiting its storage time. Herein, an electron trapping material containing deep traps is achieved by co‐doping Tb and Eu in Y3Al5O12 via solid‐state reaction in reducing atmosphere. After 254 nm UV charging, strong thermoluminescence of Tb3+ with the glow curve peaking at 600, 693, and 765 K is observed. The comparative studies of the as‐made and the air‐annealed samples suggest that these new traps are related to the complex defects containing oxygen vacancy with adjacent Eu2+ and the charging process is the photoionization of Tb3+ with subsequent electron trapping. The 693 and 765 K thermoluminescence glow peaks in the charged sample show almost no decrease during 108 h storage in dark at room temperature. Images write‐in and read‐out via 808 nm laser stimulation are realized. Furthermore, the present phosphor also exhibits temperature‐sensitive afterglow spectra in the range of 553–803 K with the sensing span of 250 K wider than other afterglow thermometers. These findings indicate the great application potentials of Y3Al5O12:Tb,Eu phosphor in long‐term optical storage and temperature sensing.

Selective Removal of Chlorophyll and Isolation of Lutein from Plant Extracts Using Magnetic Solid Phase Extraction with Iron Oxide Nanoparticles.

In recent years, there has been a growing interest in plant pigments as readily available nutraceuticals. Photosynthetic pigments, specifically chlorophylls and carotenoids, renowned for their non-toxic antioxidant properties, are increasingly finding applications beyond their health-promoting attributes. Consequently, there is an ongoing need for cost-effective methods of isolation. This study employs a co-precipitation method to synthesize magnetic iron oxide nanoparticles. Scanning electron microscopy (SEM) coupled with energy dispersive spectrometry (EDS) confirms that an aqueous environment and oxidizing conditions yield nanosized iron oxide with particle sizes ranging from 80 to 140 nm. X-ray photoelectron spectroscopy (XPS) spectra indicate the presence of hydrous iron oxide FeO(OH) on the surface of the nanosized iron oxide. The Brunauer-Emmett-Teller (BET) surface area of obtained nanomaterial was 151.4 m2 g-1, with total pore volumes of pores 0.25 cm3 g-1 STP. The material, designated as iron oxide nanoparticles (IONPs), serves as an adsorbent for magnetic solid phase extraction (MSPE) and isolation of photosynthetic pigments (chlorophyll a, lutein) from extracts of higher green plants (Mentha piperita L., Urtica dioica L.). Sorption of chlorophyll a onto the nanoparticles is confirmed using UV-vis spectroscopy, Fourier transform infrared photoacoustic spectroscopy (FT-IR/PAS), and high-performance liquid chromatography (HPLC). Selective sorption of chlorophyll a requires a minimum of 3 g of IONPs per 12 mg of chlorophyll a, with acetone as the solvent, and is dependent on a storage time of 48 h. Extended contact time of IONPs with the acetone extract, i.e., 72 h, ensures the elimination of remaining components except lutein, with a spectral purity of 98%, recovered with over 90% efficiency. The mechanism of chlorophyll removal using IONPs relies on the interaction of the pigment's carbonyl (C=O) groups with the adsorbent surface hydroxyl (-OH) groups. Based on molecular dynamics (MD) simulations, it has been proven that the selective adsorption of pigments is also influenced by more favorable dispersion interactions between acetone and chlorophyll in comparison with other solutes. An aqueous environment significantly promotes the removal of pigments; however, it results in a complete loss of selectivity.

Investigating the characteristics of biomass wastes via particle feeder in downdraft gasifier

Particle feeding plays a crucial role in the gasifier due to its effects on the efficiency and performance metrics of the thermochemical process. Investigating particle size distribution's impact on downdraft gasification reactor performance, this study delves into the significance of feedstock characteristics (moisture, volatile matter, fixed carbon, and ash contents) during the particle feeding stage. Various biomass wastes (date palm waste, olive pomace and sewage sludge) at diverse compositions and sizes are subjected to empirical determination of mass flow rates (MFR), power ratings, and storage times for each feedstock. The preheating process in the gasifier is considered, employing both an approximation and analytical solution. In addition, the influence of the equivalence ratio (ER) on the syngas yield is analyzed. The collected data reveals that for average particle size of 200 μm, the highest MFR (in g/min) are 0.518 ± 0.033, 7.691 ± 0.415, and 16.111 ± 1.050, for palm wood biomass, olive pomace and sewage sludge, respectively. Smaller particles (80 μm) led to extended storage times. Moreover, the lumped capacitance approximation method consistently underestimates preheating time, with a percentage error of 6.26%–17.08%. Response surface methodology (RSM) optimization analysis provides optimal gasification conditions for palm wood biomass, olive pomace, and sewage sludge with maximum cold gas efficiencies (CGEs) of 58.01%, 63.29%, and 52.27%. The peak conversion was attained at gasification temperatures of 1089.83 °C, 1151.93 °C, and 1102.91 °C for palm wood biomass, olive pomace, and sewage sludge, respectively. In addition, gasification equilibrium model determined optimal gasification temperatures as 1150 °C for palm biomass, 1200 °C for olive pomace, and 1150 °C for sewage sludge with respective syngas efficiencies of 59.62%, 64.13%, and 53.66%. Consequently, the examination of the dosing procedure, preheating dynamics, particle dimensions, ER, storage time, and their combined impacts offer practical insights to effectively control downdraft gasifiers in handling a variety of feedstocks.

Quantum dots (QDs) attached magnetic beads (MBs) for on-chip efficient capture and detection of bacteria in ready-to-eat (RTE) foods

In this study, we established a versatile and simple magnetic-assisted microfluidic method for fast bacterial detection. Quantum dots (QDs) were loaded onto magnetic beads (MBs) to construct performance enhanced on-chip capture of bacteria. Escherichia coli (E. coli), as a model bacterium was studied. CdSe QDs were deposited onto the surface of Fe3O4 MBs through layer-by-layer self-assembly to enhance the loading of antibodies (Abs). MBs functionalized with anti-E. coli antibody molecules in a micropillar-based microfluidic chip were utilized to capture E. coli, and matrix-assisted laser desorption ionization time-of-flight mass spectrometry (MALDI-TOF MS) was used for characterization of captured bacteria. This method was found capable of specifically isolating E. coli within the range of 1.0 to 1.0 × 109 CFU/mL, having a detection limit (LOD) of 10 CFU/mL. The average similarity score among mass spectra for the bacterial capture obtained in independent experiments is calculated as 0.97 ± 0.01 (n = 3), which shows this work's excellent reproducibility for bacterial capture. Bacterial growth on ready-to-eat (RTE) foods during its time of storage was successfully monitored. The present protocol has promising potential for microbial control and pathogen detection in the food industry.

Polydimethylsiloxane surface irradiated by nitrogen ions: Influence of low molecular fractions

Polydimethylsiloxane (PDMS) surface was treated by nitrogen ions of 20 keV energy with 1016 ions/cm2 fluence. The surface of modified PDMS is characterized by ceramiclike structures. The treated PDMS contains free radicals. The wettability and surface energy change significantly immediately after the treatment and recover in a few days to the values of silicon dioxide or glass. Complex kinetics of growing carbonyl and hydroxyl groups and decaying silane groups is observed. The cage structure of the silicon oxide in the surface ceramiclike layer remains stable, while network structures of the Si–O increase and suboxides of the silicon decrease with storage time. The presence of not-cross-linked low molecular fractions in PDMS gives a fast recovery of the wettability and surface energy to untreated PDMS values in a few hours. This effect of low molecular fractions on the wettability and surface energy was avoided by washing out the cured PDMS in a solvent before the treatment.