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Over the past decades, particulate matter (PM), especially fine PM2.5 μm in aerodynamic diameter (PMCardiovascular cases were identified through the Gunma Prefectural Ambulance Activity Database in Japan in 2015 (1,512 out-of-hospital cardiac arrest [OHCA] and 1,002 heart failures from 53,006 ambulance cases). Air quality data from the nearest station was for day of the arrest (lag0) and 1-2 days before the arrest (lag1, lag2) and the moving average across days 0-1 (lag0-1). Conditional logistic regression was used for unadjusted and adjusted analysis for temperature and humidity.Independent associations of OHCA were daily concentrations of SOShort-term exposure to SO

In this study, the performance of polyethersulfone (PES) membranes, fabricated by modifying the iron nano-particles (M-Fe3O4), was investigated to remove heavy metals (HM) and Direct red 16 (DR16) dye from water. In this new research work, amine groups were first fixed on nano-particles by modifying iron nano-particles using TEOS and APTES methods. In the next step, M-Fe3O4 was used in the structure of membranes, and their effect on surface properties, hydrophilicity (HD), pure water (PW) flux, roughness (Ra), water permeability and removal rate of copper ion (CI) and DR16 dye were investigated. Also, characterization methods such as X-ray powder diffraction (XRD), scanning force microscopy (SEM), Fourier transform infrared spectroscopy (FT-IR), atomic force microscopy (AFM), and antifouling properties have been used to evaluate the synthetic membranes. Thus, the performance of composite membranes showed that the pure water (PW) flux of the membrane M-Fe3O4 increased 1.9 times compared to the pure membrane. Moreover, the anti-fouling tests showed that the mixed matrix membranes (MMM) with 0.1 wt% of M-Fe3O4 showed the best anti-fouling properties with a 90% recovery rate and 55.98% fouling resistance. On the other hand, results showed that 0.1 wt% composite membrane resulted in the removal of CIs 92% and dye 99%.

One of the advanced proceedings in the petroleum industry is the use of nanotechnology for better oil recovery. Therefore, in this study, Nano-Graphene (NG) was firstly synthesized by the Hummer’s ...

In this study, bentonite/TiO2 and bentonite/ZnO nanoparticles were used for studying the cadmium removal from the aqueous solution. The experiments were done in a batch condition under solar light. The nanoparticles characteristics were determined using analytical devices such as scanning electronic microscopy (SEM), X-ray diffraction (XRD), Transmission electron microscopy (TEM), Fourier-transform infrared spectroscopy (FTIR) and the N2 absorption. The optimum condition of the adsorption process was obtained at an initial concentration of 6 ppm, time of 6 h, 45 °C temperature, 4 g/L bentonite/ZnO (pH = 5) and 2 g/L for bentonite/TiO2 (pH = 7). Also, the cadmium removal increased for bentonite/TiO2 adsorbent with increasing the light intensity but it had no effect on the bentonite/ZnO adsorbent. In this work, the adsorption isotherm and kinetics were investigated and results showed that the adsorption process followed better by Temkin isotherm and the adsorption kinetics better described by the pseudo-second-order model.

The small size and large surface area of ultrafine particles (UFP) enhance their ability to deposit in the lung periphery and their reactivity. The Ultrafine Particles from Traffic Emissions and Children's Health (UPTECH) cross-sectional study was conducted in 8-11-year-old schoolchildren attending 25 primary (elementary) schools, randomly selected from the Brisbane Metropolitan Area, Queensland, Australia. Main study findings outlined indirect evidence of distal airway deposition (raised C reactive protein) but as yet, there is no direct evidence in the literature of effects of UFP exposure on peripheral airway function. We present further UPTECH study data from two sensitive peripheral airway function tests, Oscillometry and Multiple Breath Nitrogen Washout (MBNW), performed in 577 and 627 children (88% and 96% of UPTECH study cohort) respectively: mean(SD) age 10.1(0.9) years, 46% male, with 50% atopy and 14% current asthma. Bayesian generalised linear mixed effects regression models were used to estimate the effect of UFP particle number count (PNC) exposure on key oscillometry (airway resistance, (Rrs), and reactance, (Xrs)) and MBNW (lung clearance index, (LCI) and functional residual capacity, (FRC)) indices. We adjusted for age, sex, and height, and potential confounders including socio-economic disadvantage, PM

We aimed to determine the associations between ambient air pollution, specifically particulate matter less than or equal to 10 microns and 2.5 microns (PM10 and PM2.5 respectively) and ozone (O3), and stillbirths. We analysed all singleton births between 20–42 weeks gestation in metropolitan Sydney, Australia, from 1997 to 2012. We implemented logistic regression to assess the associations between air pollutants and stillbirth for each trimester and for the entire pregnancy. Over the study period, there were 967,694 live births and 4287 stillbirths. Mean levels of PM10, PM2.5 and O3 for the entire pregnancy were 17.9 µg/m3, 7.1 µg/m3 and 3.2 ppb, respectively. Adjusted odds ratios were generally greater than unity for associations between PM and stillbirths, but none were statistically significant. There were no significant associations between O3 and stillbirths. There was potential effect modification of the PM10 and O3 association by maternal age. We did not find consistent evidence of associations between PM and O3 and stillbirths in Sydney, Australia. More high quality birth cohort studies are required to clarify associations between air pollution and stillbirths.

Supplemental Digital Content is available in the text., Background: Ambulance data provide a useful source of population-based and spatiotemporally resolved information for assessing health impacts of air pollution in nonhospital settings. We used the clinical records of paramedics to quantify associations between particulate matter (PM2.5) and diabetic, cardiovascular, and respiratory conditions commonly managed by those responding to calls for emergency ambulance services. Methods: We evaluated 394,217 paramedic assessments from three states in Southeastern Australia (population 13.2 million) and daily PM2.5 concentrations modeled at 5 km resolution from 2009 to 2014. We used a time-stratified, case-crossover analysis adjusted for daily meteorology to estimate the odds ratios (ORs) and 95% confidence intervals (CIs) for each clinical outcome per 10 µg/m3 increase in daily PM2.5 at lags from 0 to 2 days. Results: Increased PM2.5 was associated with increased odds of paramedic assessments of hypoglycemia (OR = 1.07; 95% CI = 1.02, 1.12, lag 0), arrhythmia (OR = 1.05; 95% CI = 1.02, 1.09, lag 0), heart failure (OR = 1.07; 95% CI = 1.02, 1.12, lag 1), faint (OR = 1.09; 95% CI = 1.04–1.13, lag 0), asthma (OR = 1.06; 95% CI = 1.01, 1.11, lag 1), chronic obstructive pulmonary disease (OR = 1.07; 95% CI = 1.01, 1.13, lag 1), and croup (OR = 1.09; 95% CI = 1.02, 1.17). We did not identify associations with cerebrovascular outcomes. Conclusions: Ambulance data enable the evaluation of important clinical syndromes that are often initially managed in nonhospital settings. Daily PM2.5 was associated with hypoglycemia, faint, and croup in addition to the respiratory and cardiovascular outcomes that are better established.

Density measurements are used to calculate the apparent molar volumes Vφ, limiting apparent molar volumes $$V_{\varphi }^{0}$$ , limiting apparent molar volumes of transfer, $$\Delta_{\text{t}} V_{\varphi }^{0}$$ , limiting apparent molar expansibilities, $$E_{\varphi }^{0}$$ , and hydration numbers nH, for dl-alanine and glycine in aqueous solutions of l(+)-arabinose at T = 293.15 to 313.15 K. To obtain the limiting apparent molar volume, the Vφ values are extrapolated to zero molality using the linear form of the Redlich–Meyer equation. Also, the limiting apparent molar volumes of transfer, $$\Delta_{\text{t}} V_{\varphi }^{0}$$ , for the amino acids, from water to aqueous l(+)-arabinose solutions, are calculated from the $$V_{\varphi }^{0}$$ values. The limiting apparent molar expansibility, $$E_{\varphi }^{0}$$ , values have been obtained from the first derivative of limiting apparent molar volumes with respect to temperature. Also the hydration number, nH, for both amino acids in the ternary solutions are estimated. Possible solute–solvent interactions in the studied ternary systems are discussed.

The density and viscosity measurements have been performed for the ternary ( dl -alanine/+ d (−)-fructose + water) system at T = 293.15, 298.15, 303.15, 308.15, 313.15 K and ambient pressure. By using the obtained experimental densities, the apparent molar volume, limiting partial molar volumes, limiting apparent molar volume of transfer, limiting apparent molar expansibility and hydration number are calculated for dl -alanine in the aqueous d (−)-fructose solution. Redlich-Mayer type equation has been applied for correlating the apparent molar volume values in dilute region. The obtained viscosity data in the whole concentration range were correlated to the Jones-Dole semi-empirical equation. The viscosity B-coefficients were obtained by fitting viscosity data to Jones-Dole equation. It is well established that the viscosity B-coefficient is a measure of solute–solvent interactions, and is directly dependent on the size, shape and charge of the solute molecules. With helping the obtained results from the volumetric and viscometric measurements, we are able to describe the nature of possible interactions in the studied ternary system.

Many Australians are intermittently exposed to landscape fire smoke from wildfires or planned (prescribed) burns. This study aimed to investigate effects of outdoor smoke from planned burns, wildfires and a coal mine fire by assessing biomarkers of inflammation in an exposed and predominantly older population. Participants were recruited from three communities in south-eastern Australia. Concentrations of fine particulate matter (PM2.5) were continuously measured within these communities, with participants performing a range of health measures during and without a smoke event. Changes in biomarkers were examined in response to PM2.5 concentrations from outdoor smoke. Increased levels of FeNO (fractional exhaled nitric oxide) (&beta, = 0.500 [95%CI 0.192 to 0.808] p &lt, 0.001) at a 4 h lag were associated with a 10 &micro, g/m3 increase in PM2.5 levels from outdoor smoke, with effects also shown for wildfire smoke at 4, 12, 24 and 48-h lag periods and coal mine fire smoke at a 4 h lag. Total white cell (&beta, = &minus, 0.088 [&minus, 0.171 to &minus, 0.006] p = 0.036) and neutrophil counts (&beta, 0.077 [&minus, 0.144 to &minus, 0.010] p = 0.024) declined in response to a 10 &micro, g/m3 increase in PM2.5. However, exposure to outdoor smoke resulting from wildfires, planned burns and a coal mine fire was not found to affect other blood biomarkers.

OBJECTIVES: To describe the characteristics and outcomes of patients with COVID-19 admitted to intensive care units (ICUs) during the initial months of the pandemic in Australia. DESIGN, SETTING: Prospective, observational cohort study in 77 ICUs across Australia. PARTICIPANTS: Patients admitted to participating ICUs with laboratory-confirmed COVID-19 during 27 February - 30 June 2020. MAIN OUTCOME MEASURES: ICU mortality and resource use (ICU length of stay, peak bed occupancy). RESULTS: The median age of the 204 patients with COVID-19 admitted to intensive care was 63.5 years (IQR, 53-72 years); 140 were men (69%). The most frequent comorbid conditions were obesity (40% of patients), diabetes (28%), hypertension treated with angiotensin-converting enzyme inhibitors or angiotensin II receptor blockers (24%), and chronic cardiac disease (20%); 73 patients (36%) reported no comorbidity. The most frequent source of infection was overseas travel (114 patients, 56%). Median peak ICU bed occupancy was 14% (IQR, 9-16%). Invasive ventilation was provided for 119 patients (58%). Median length of ICU stay was greater for invasively ventilated patients than for non-ventilated patients (16 days; IQR, 9-28 days v 3 days; IQR, 2-5 days), as was ICU mortality (26 deaths, 22%; 95% CI, 15-31% v four deaths, 5%; 95% CI, 1-12%). Higher Acute Physiology and Chronic Health Evaluation II (APACHE-II) scores on ICU day 1 (adjusted hazard ratio [aHR], 1.15; 95% CI, 1.09-1.21) and chronic cardiac disease (aHR, 3.38; 95% CI, 1.46-7.83) were each associated with higher ICU mortality. CONCLUSION: Until the end of June 2020, mortality among patients with COVID-19 who required invasive ventilation in Australian ICUs was lower and their ICU stay longer than reported overseas. Our findings highlight the importance of ensuring adequate local ICU capacity, particularly as the pandemic has not yet ended.

A key measure of lung function in people with Cystic Fibrosis (CF) is Forced Expiratory Volume in the first second FEV1 percent predicted (FEV1pp). This study aimed to address challenges in identifying predictors of FEV1pp, specifically dealing with non-linearity and the censoring effect of death. Data was obtained from a large multi-centre Australian Cystic Fibrosis Data Registry (ACFDR). A linear mixed model was used to study FEV1pp as the endpoint. There were 3655 patients (52.4% male) included in our study. Restricted cubic splines were used to fit the non-linear relationship between age of visit and FEV1pp. The following predictors were found to be significant in the multivariate model: age of patient at visit, BMI z-score, age interaction with lung transplantation, insulin dependent diabetes, cirrhosis/portal hypertension, pancreatic insufficiency, Pseudomonas aeruginosa infection and baseline variability in FEV1pp. Those with P. aeruginosa infection had a lower mean difference in FEV1pp of 4.7 units, p

The International Agency of Research on Cancer identifies high-temperature frying, which features prominently in Chinese cooking, as producing group 2A carcinogens. This study simultaneously characterized particulate and gaseous-phase cooking emissions, monitored their reactive oxygen species (ROS) concentrations, and evaluated their impact on genetic damage and expression in exposed human bronchial epithelial cells. Five types of edible oil, three kinds of seasonings, and two dishes were assessed. Among tested edible oils, heating of soybean oil released the largest particle number concentration (2.09 × 1013 particles/(g cooking material and oil)·h) and volatile organic compounds (VOCs) emissions (12103.42 μg/(g cooking material and oil)·h). Heating of lard produced the greatest particle mass concentration (0.75 mg/(g cooking material and oil)·h). The main finding was that sunflower and rapeseed oils produced the highest ROS concentrations (80.48 and 71.75 nmol/(g cooking material and oil)·h, respectively). ROS formation most likely occurred during the autoxidation of both polyunsaturated and monounsaturated fatty acids. Among all the tested parameters, only ROS concentrations exhibited consistency with cell viability and showed significant correlations with the expression levels of CYP1A1, HIF-1a, and especially with IL-8 (the marker for oxidative stress within the cell). These findings indicate that ROS concentration is potentially a suitable metric for direct assessment of exposure levels and potential toxicity.

To estimate the oxidative potential (OP) of particulate matter (PM), two commonly used cell-free, molecular probes were applied: dithiothreitol (DTT) and dichloro-dihydro-fluorescein diacetate (DCFH-DA), and their performance was compared with 9,10-bis (phenylethynyl) anthracene-nitroxide (BPEAnit). To the best of our knowledge, this is the first study in which the performance of the DTT and DCFH has been compared with the BPEAnit probe. The average concentrations of PM, organic carbon (OC) and elemental carbon (EC) for fine (PM2.5) and coarse (PM10) particles were determined. The results were 44.8 ± 13.7, 9.8 ± 5.1 and 9.3 ± 4.8 µg·m−3 for PM2.5 and 75.5 ± 25.1, 16.3 ± 8.7 and 11.8 ± 5.3 µg·m−3 for PM10, respectively, for PM, OC and EC. The water-soluble organic carbon (WSOC) fraction accounted for 42 ± 14% and 28 ± 9% of organic carbon in PM2.5 and PM10, respectively. The average volume normalized OP values for the three assays depended on both the sampling periods and the PM fractions. The OPBPEAnit had its peak at 2 p.m.; in the afternoon, it was three times higher compared to the morning and late afternoon values. The DCFH and BPEAnit results were correlated (r = 0.64), while there was no good agreement between the BPEAnit and the DTT (r = 0.14). The total organic content of PM does not necessarily represent oxidative capacity and it shows varying correlation with the OP. With respect to the two PM fractions studied, the OP was mostly associated with smaller particles.

Introduction The cardiovascular health consequences of ambient air pollution generally equal or exceed those due to pulmonary diseases and cancers. Particulate matter less than 2.5μm in aerodynamic diameter (PM2.5) has become a major focus of research on the short-term exposure to air pollution and cardiovascular disease. However, the evidence regarding the association between several air pollutants and out-of-hospital cardiac arrest (OHCA), has been inconsistent, which could be due to limited sample sizes (∼11,000). Thus, a larger study may assist in characterising possible associations. Purpose This study aimed to identify the associations between exposure to ambient air pollution and the incidence of OHCA in Japan. Methods A case-crossover design was used to determine the odds ratio (OR) of OHCA across Japan with daily exposure of PM2.5, carbon monoxide (CO), photochemical oxidants (Ox), and sulfur dioxide (SO2) on the day of the arrest or 1–3 days before it (lag 0–3). OHCA cases were identified through the All-Japan Utstein registry of the Fire and Disaster Management Agency from January 1, 2014 to December 31, 2015. All cause OHCAs were investigated by conditional logistic regression adjusted for daily temperature and relative humidity. Results A total of 249,372 OHCAs were included during study period. Each 10 μg/m3 increase in daily PM2.5 exposure over 4 days was associated with all cause OHCA risk (lag 0: OR 1.017, 95% confidence interval (CI) 1.010, 1.024; lag 1: OR 1.015, 95% CI 1.008, 1.022; lag 2: OR 1.018, 95% CI 1.011, 1.025; lag 3: OR 1.021, 95% CI 1.014, 1.028; lag 0–1: OR 1.022, 95% CI 1.014, 1.030). CO, Ox and SO2 also showed significant associations with OHCAs. In the multi-pollutant model, the effects of PM2.5 remained independent of CO, Ox and SO2 (Table). Conclusion Short-term exposure to PM2.5 was independently associated with an increased risk of OHCA.

Introduction Accumulating evidence has shown the elevated risk for cardiovascular diseases (CVD) with exposure to air pollution, such as fine particles Purpose This study aimed to identify sex and age differences in the associations between exposure to PM2.5 and OHCA in Japan. Methods A case-crossover design was used to determine the odds ratio (OR) of OHCA across Japan with daily PM2.5 exposure on the day of the arrest or 1–3 days before it (lag 0–3). OHCA cases were identified through the All-Japan Utstein registry of the Fire and Disaster Management Agency from January 1, 2014 to December 31, 2015. OHCAs were investigated by conditional logistic regression adjusted for daily temperature and relative humidity with stratification by sex and age. Results A total of 249,372 OHCAs were included during study period. Their mean age was 75 years and 57% were male. Each 10 μg/m3 increase in daily PM2.5 exposure over 4 days was associated with all cause OHCA risk for male (lag 0: OR 1.022, 95% confidence interval (CI) 1.013, 1.031; lag 1: OR 1.016, 95% CI 1.007, 1.025; lag 2: OR 1.016, 95% CI 1.007, 1.026; lag 3: OR 1.017, 95% CI 1.008, 1.027; lag 0–1: OR 1.025, 95% CI 1.015, 1.036). Increased risk in OHCA was also found with lag 1 to lag 3 PM2.5 exposure among women. Lag 0 to lag 3 PM2.5 exposures were significantly associated with OHCA among patients older than 65 years. Among 35 to 64 years, only lag 3 PM2.5 exposure was associated with an increased risk in OHCA. No significant association was observed between PM2.5 exposure and OHCA among patients less than 35 years. Conclusions Short-term exposure to PM2.5 is associated with an increased risk of OHCA in both sexes. Patients older than 65 years were more susceptible to PM2.5 exposure than younger age group.

Heavy metal pollution is one problem in the water purification industry, which causes extreme risk aversion. The purpose of this study was to investigate the removal of arsenic (As) and copper (Cu) from water by nanoparticles of magnetic iron bentonite (Fe3O4/bentonite). Fe3O4/bentonite nanoparticles were prepared by chemical co-precipitation method. The synthesized samples were characterized using scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FTIR) and X-ray diffraction patterns (XRD) techniques. The results of the XRD and FTIR confirmed the successful synthesis of the Fe3O4/bentonite nanoparticles. The results of the SEM showed that the Fe3O4/bentonite nanoparticles had symmetrical, bullet-shaped particles with uniform size. Then, by performing modular experiments, the effect of time, temperature and pH parameters was investigated on the pollutants adsorption rate in an aqueous solution. The results showed that the adsorption capacity for ions increased by increasing the contact time, temperature and adsorbent dosage of the solution The results indicated that the optimum condition was achieved at temperature of 75 ∘C, reaction time of 120 min, the adsorbent dosage of 5 g/l and pH of 6 and 4 for Cu and As, respectively. Langmuir and Freundlich isotherms were employed to modeling of the experimental results. The best results in the modeling prosess for the experiment results were obtained based on the Freundlich isotherm. The kinetic data were also analyzed through pseudo-first-order and pseudo-second-order models. The pseudo-first-order kinetic model well depicted the kinetics of heavy metals ions adsorption on adsorbent.

It is known that ultrafine particles (UFP, particles smaller than 0.1 μm) can penetrate deep into the lungs and potentially have adverse health effects. However, epidemiological data on the health effects of UFP is limited. Therefore, our objective was to test the hypothesis that exposure to UFPs is associated with respiratory health status and systemic inflammation among children aged 8 to 11 years.We conducted a cross-sectional study among 655 children (43.3% male) attending 25 primary (elementary) schools in the Brisbane Metropolitan Area, Australia. Ultrafine particle number concentration (PNC) was measured at each school and modelled at homes using Land Use Regression to derive exposure estimates. Health outcomes were respiratory symptoms and diagnoses, measured by parent-completed questionnaire, spirometric lung function, exhaled nitric oxide (FeNO), and serum C reactive protein (CRP). Exposure-response models, adjusted for potential personal and environmental confounders measured at the individual, home and school level, were fitted using Bayesian methods.PNC was not independently associated with respiratory symptoms, asthma diagnosis or spirometric lung function. However, PNC was positively associated with an increase in CRP (1.188-fold change per 1000 UFP cm−3 day/day (95% credible interval 1.077 to 1.299)) and an increase in FeNO among atopic participants (1.054 fold change per 1000 UFP cm−3 day/day (95% CrI 1.005 to 1.106)).UFPs do not affect respiratory health outcomes in children but do have systemic effects, detected here in the form of a positive association with a biomarker for systemic inflammation. This is consistent with the known propensity of UFPs to penetrate deep into the lung and circulatory system. Keywords: Ultrafine particles, Exposure, Schoolchildren, Respiratory health, Systematic inflammation

In this research, the effect of surface roughness and concentration of solution on bubble departing frequency and nucleation site density for pool boiling of water/diethanolamine (DEA) binary solution were investigated experimentally. In this investigation, boiling heat transfer coefficient, bubble departing frequency and nucleation site density have been experimentally investigated in various concentrations and heat fluxes. Microstructured surfaces with a wide range of well-defined surface roughness were fabricated, and a heat flux between 1.5–86 kW/m2 was achieved under atmospheric conditions. The Results indicated that surface roughness and concentration of solution increase the bubble departing frequency and nucleation site density with increasing heat flux. The boiling heat transfer coefficient in mixtures of water/DEA increases with increasing concentration of DEA in water. The experimental results were compared with predictions of several used correlations in the literatures. Results showed that the boiling heat transfer coefficients of this case study are much higher than the predicted values by major existing correlations and models. The excellent agreement for bubble departing frequency found between the models of Jackob and Fritz (1966) and experimental data and also the nucleation site density were in close agreement with the model of Paul (1983) data. f bubble departure frequency, 1/s or Hz N Number of nucleation sites per area per time Rc Minimum cavity size, m Dc critical diameter, m g gravitational acceleration, m/s2 ρ density, kg/m3 T temperature, °c ΔT temperature difference, °c dd vapor bubble diameter, m hfg enthalpy of vaporization, J/kg R Roughness, μm Ja Jakob number cp specific heat, J/kg °c Pr Prandtl number Ar Archimedes number h Heat transfer coefficient, J/(m2 °c) tg time it takes to grow a bubble, s q/A heat flux (kW/m2) tw time required to heat the layer, s gc Correction coefficient of incompatible units Ra Surface roughness A heated surface area d departure ONB onset of nucleate boiling w surface wall s saturation v vapor l liquid θ groove angle (o) γ influence parameter of heating surface material σ surface tension, N/m.

The present work describes a simple method for the preparation of gold nanoparticles (AuNPs) in aqueous media under ambient conditions and their use in colorimetric detection of Cr (III) and Fe (II) ions. The AuNPs were prepared using methylene blue (MB) as the capping agent and sodium borohydride as the reducing agent in the aqueous medium. The prepared MB-AuNPs were thoroughly characterized using UV–vis spectroscopy, TEM, and FT-IR techniques. The MB-AuNPs were employed as colorimetric for Cr (III) and Fe (II) ions at pH range of 3–8, at room temperature in aqueous solution. In the present of Cr (III) and Fe (II) ions, the MB-AuNPs induces aggregation of the nanoparticles. Upon aggregation, the surface plasmon absorption band red-shifts so that the nanoparticle solution appears a blue color. The MB-AuNPs were found to be highly sensitive to Cr (III) and Fe (II) ions with the detection limit 23.66 and 11.21 nM respectively under optimized conditions in the aqueous medium.

In this study, asphaltene deposition from crude oil has been studied experimentally using a test loop and prediction using theoretical study under turbulent flow (Reynolds numbers below 5000). The effects of many parameters such as oil velocity, surface temperature and concentration of flocculated asphaltene on the asphaltene deposition were investigated. The results showed that asphaltene deposition thickness increases with increasing both surface temperature and concentration of flocculated asphaltene and decreasing oil velocity. Thermal approach was used to describe the mechanisms involved in this process and the results of data fitting showed that there are good agreements between the results of the proposed model and the measured asphaltene deposition rates.

This paper reports the synthesis of ribavirin-modified gold nanoparticles (ribavirin-AuNPs) in aqueous media, characterized by FTIR spectroscopy, ultraviolet–visible spectroscopy (UV–vis), and transmission electron microscopy (TEM). Ribavirin-AuNPs were employed as colorimetric probes to detect Cr3+ and Ni2+ in the pH range of 3–8 and 25 ∘C in aqueous solutions by the color change of the system. In the solution, ribavirin-AuNPs were red in color and the surface plasmon absorption band was centered at 530 nm. In the presence of Cr3+ and Ni2+, ribavirin-AuNPs induced the aggregation of nanoparticles, and the surface plasmon absorption changed to 540 nm. Upon aggregation, the surface plasmon absorption band red-shifted and, thus, the nanoparticle solution appeared blue. The sensitivity of ribavirin-AuNPs toward other metal ions, i.e. Mg2+, Mn2+, Cr6+, Na+, Ni2+, Ag+, Al3+, Ca2+, Cd2+, K+, Cd2+, Cu2+, Fe2+, Fe3+, Hg2+, Co3+, Ni2+, Pb2+, and Zn2+, was negligible. This highly selective sensor allowed for the direct quantitative assay of Ni2+ and Cr3+. The limits of detections were found to be 25.2 and 30.5 nM for Ni2+ and Cr3+ on the basis of the signal-to-noise ratio of 3:1 and correlation coefficients (R2) of 0.9813 and 0.99489 for Ni2+ and Cr3+, respectively.

In this study, nano catalyst LaNiO3 with perovskite structure was synthesized using the citrate sol–gel method in the combined methane reforming with CO2 and O2 (CRM). The effects of increasing the surface area of the LaNiO3 perovskite on the catalytic activity were investigated by changing the method of preparing and creating holes in the surface of the samples. Physical and chemical properties of the samples, before and after the reactor test, were determined through ICP, AA, XRD, TGA, TPR, BET, SEM, EDX and TEM techniques. The results of XRD, ICP, AA, SEM, EDX and TEM tests indicated that the citrate sol–gel method is a good way to prepare a homogeneous perovskite LaNiO3 sample on a scale of nanometers. The results of the TPR test showed using etching in the citrate sol–gel method can produce samples with high stability. The BET results indicated that the surface area of the LaNiO3 sample tripled with the method suggested in this paper. Changes in preparation method lead to induction time decreasing and temperature increasing. Use of etching in the citrate sol gel method had no significant effect in the results of activity tests versus time reaction at a temperature of 800 °C. TGA curves revealed no production of coke over the process for the produced samples.

Chromium is one of the hazardous pollutants in industrial effluents. In this study, a new nano-boehmite modified with sodium dodecyl sulphate is developed for preconcentration trace amounts of chromium ions as a prior step to its determination by flame atomic absorption spectrometry. We investigated the effect of various parameters on the recovery of the analyte ions, including pH of sample solution, amount of sorbent, sample volume on extraction efficiency of the chromium ions. Under the best experimental conditions, the calibration curve was linear in the range of 1.0 -700.0 ng.mL-1 of chromium with R2 = 0.997. Detection limit was 0.6 ng.mL-1 in the original solution (3Sb/m) and the relative standard deviation for seven replicate determination of 0.5 µg.mL-1 chromium was ±2.4%. The developed method was successfully applied to the extraction and determination of chromium in water and food samples with satisfactory results.

In this work, a comparison study was implemented on the pool boiling heat transfer coefficient (BHTC) between the copper sulfate and isopropanol solutions. To precise investigate; the bubble dynamic including departure diameter, departure frequency and active nucleation sites were examined. In addition, ultrasonic waves’ irradiation (25 kHz) was employed to intensive the solutions and improve the dynamic parameters due to cavitation phenomenon. First, although the cooper sulfate had a bigger bubble departure diameter and more active nucleation sites than isopropanole, its heat transef coefficient was lower due to great bubble departure frequency of isopropanol. Finally, Calus model with an average error of 12.8% for isopropanol and Palen with 13.1% for copper sulfate had the lowest errors. Moreover, the isoropanole at 20 V.% with 15% power of ultrasonic irradiation and the cooper sulfate at 10.5 V.% with 35% had the maximum increase in the BHTC as 10.549% and 18.238%, respectively.