Study of efficacy of date kernel ash on removal of nitrate from aqueous solutions (isothermic and kinetic study)

زمینه و هدف: در چند دهه گذشته، حضور غلظت بالای نیترات در آب آشامیدنی به یک نگرانی جدی تبدیل شده که باعث بروز اختلالاتی در سلامتی انسان به خصوص اطفال می شود؛ که با استفاده از روش های فیزیکی- شیمیایی و بیولوژیکی می توان آنرا حذف نمود. در این تحقیق میزان حذف نیترات از محلول های آبی با استفاده از خاکستر هسته خرما، مورد بررسی قرار گرفت. روش بررسی: در این مطالعه تجربی که در مقیاس آزمایشگاهی انجام شد، اثر غلظت اولیه نیترات (50، 100 و 150 میلی گرم بر لیتر) با PH (3، 5، 7 و 9)، زمان ماند (15، 30، 60، 120 و 180 دقیقه) و وزن جاذب (4/0، 6/0 و 8/0 گرم) مورد بررسی قرار گرفت. غلظت نیترات با استفاده از دستگاه اسپکتروفتومتر در دو طول موج 220 و 275 نانومتر اندازه گیری شد. کلیه آزمایشات و آنالیز نمونه به روش کتاب روش های استاندارد آب و فاضلاب انجام شد. یافته ها: افزایش دوز جاذب از 4/0 گرم به 8/0 گرم در 100 میلی لیتر از محلول نیترات با غلظت 50 و 100 میلی گرم در لیتر به ترتیب منجر به افزایش راندمان جذب از 75 به 91 و از 53 به 65 گردید. افزایش PH اولیه محلول از 3 به 9 منجر به کاهش راندمان جذب از 52 به 8 شد. داده های به دست آمده در این تحقیق، از ایزوترم فروندلیچ (98/0R2=) و جذب نیترات از مدل سینتیکی شبه درجه دوم تبعیت می کند (999/0R2=). نتیجه گیری: نتایج مطالعه حاضر نشان داد که خاکستر هسته خرما جاذب طبیعی و ارزان قیمتی است که می توان از آن برای حذف آلاینده های زیست محیطی استفاده کرد

The Efficiency of Peroxone Process in Packed Reactor for Removal of Anionic Surfactants and COD from Carwash Wastewater

Background: Carwash is an industry that consumes large amounts of water and its wastewater contains a variety of pollutants. The aim of this study was to investigate the efficiency of the Peroxone process as a method for wastewater treatment of carwashes. Methods: This study was conducted at laboratory scale. A total of 54 samples were collected from a carwash in Yazd city and COD and anionic surfactants removal percentages were respectively determined by using the standard vial and anionic surfactants method and Methylene Blue Active Substances (MBAS). The process was conducted with an ozone dose of 0.7 mg per min, H2O2 concentrations of 10, 20 and 40 mmol per liter, reaction times of 30, 60 and 90 min and pH of 7, 9 and 11 in a cylindrical reactor respectively. Data were analyzed using ANOVA and through SPSS 18. Results: The removal efficiencies of COD and anionic surfactants increased with increasing pH and reaction time; so that, at pH =11 and after a reaction time of 90 minutes for an ozone dose of 0.7 mg/min and H2O2 concentration of 40 mmol/l, removal efficiency of COD and anionic surfactants were respectively 74.77% and 74.27%. Conclusion: The peroxone process has a good ability for removal of COD and anionic surfactants. Similar studies confirm the findings of this study. Meanwhile, pretreatment methods are recommended for further evaluation of this process

The Impact of Greenhouse Density on Cognitive Function in Primary School Children Using the WISC Method

Exposure to pesticides is associated with various health concerns and may also be related to impaired cognitive function. This study investigated the relationship between greenhouse density and cognitive function in primary school children using Wechsler Intelligence Scale for Children-Fourth Edition (WISC-IV) and environmental sampling. This study was conducted on 128 children (6–9 years old) in Ebrahimabad village, Ashkezar, Yazd, Iran in 2019, and 10 students were excluded from the study after filling consent form. The WISC-IV measured children’s cognitive function, and a flame ionization detector for gas chromatography (GC-FID) instrument was used to detect environmental exposure to pesticides. There was a significant inverse relationship between greenhouse density in children’s homes and cognitive function scores with verbal thinking scores (P value=0.003) and the total scale (P value=0.0001) on the WISC. Further, the results showed that the obtained verbal thinking scores are significantly related to their fathers’ education (P value=0.008) and occupation (P value=0.014). Moreover, the results of environmental exposure measurement confirmed the presence of malathion, ethion, chlorpyrifos, dieldrin, and oxadiazine with a maximum concentration of 183 µg/m3 in response to malathion. The present study indicated that increasing the density of the greenhouse reduces children’s cognitive functions. The results of ambient air analysis confirmed the environmental exposure to pesticides as well. Due to long-term chemical effects, management measures such as public education, substituting crop types, and the use of eco-friendly methods are unavoidable

Relationship between Religious Orientation, Anxiety, and Depression among College Students: A Systematic Review and Meta-Analysis

Background: Religious obligation helps people to develop mental health by creating internal commitment to special rules. This meta-analysis aimed to determine the relationship between religious orientation and anxiety among college students. Methods: Major scientific databases including PubMed, Web of Science, Science Direct, EBSCO, ProQuest and PsycINFO were searched for original research articles published 1987-2016. A random effect model was used to combine Correlation coefficient. All analyses were performed using Stata MP. Results: After screening of 7235 documents, 13 articles including 5620 participants met inclusion criteria in this meta-analysis. Correlation coefficient was -0.08 (95% CI= -0.19, -0.03) which indicated with increasing religious orientation, anxiety and depression reduced (P<0.001). Characteristics such as sex, geographic region, and type of religions were potential sources of heterogeneity. Based on fill-and-trim method the adjusted pooled r was obtained, -0.06 (95% CI= -0.16, -0.04). Conclusion: There was a weakness relationship between religious orientation and mental anxiety and depression. Therefore, it needs to improve knowledge of student about advantages of religious orientation

Relationship between Religious Orientation, Anxiety, and Depression among College Students: A Systematic Review and Meta-Analysis.

BACKGROUND: Religious obligation helps people to develop mental health by creating internal commitment to special rules. This meta-analysis aimed to determine the relationship between religious orientation and anxiety among college students. METHODS: Major scientific databases including PubMed, Web of Science, Science Direct, EBSCO, ProQuest and PsycINFO were searched for original research articles published 1987-2016. A random effect model was used to combine Correlation coefficient. All analyses were performed using Stata MP. RESULTS: After screening of 7235 documents, 13 articles including 5620 participants met inclusion criteria in this meta-analysis. Correlation coefficient was -0.08 (95% CI= -0.19, -0.03) which indicated with increasing religious orientation, anxiety and depression reduced (P<0.001). Characteristics such as sex, geographic region, and type of religions were potential sources of heterogeneity. Based on fill-and-trim method the adjusted pooled r was obtained, -0.06 (95% CI= -0.16, -0.04). CONCLUSION: There was a weakness relationship between religious orientation and mental anxiety and depression. Therefore, it needs to improve knowledge of student about advantages of religious orientation. KEYWORDS: Anxiety; Depression; Meta-analysis; Religious orientatio

Determination of Iron Species by Combination of Solvent Assisted-Dispersive Solid Phase Extraction and Spectrophotometry

A simple, rapid and sensitive solvent assisted-dispersive solid phase extraction method was developed for the extraction of iron(II) prior to its spectrophotometric determination. The Fe(II) reacted with 2,4,6-tris(2-pyridyl)-1,3,5-triazine, neutralized with sodium dodecyl sulfate and extracted onto the fine particles of benzophenone which were formed upon rapid injection of a mixture of benzophenone as the sorbent and ethanol as the disperser solvent into the aqueous solution. After phase separation, the sedimented phase containing the complex was dissolved in ethanol and the analyte concentration was determined by measuring its absorption at 594 nm. Total iron was determined after the reduction of Fe(III) to Fe(II) with hydroxylamine hydrochloride. Under the optimized conditions, an enhancement factor of 32, the detection limit of 0.16 µg l-1, and the relative standard deviation of 1.9% (n = 6) at 20 µg l-1 concentration level of Fe(II) were achieved. The method was successfully applied to the determination of iron species in water samples and total iron in infant dry formula milk, apple, rice, spinach and parsley samples

Identification, classification and management of industrial waste in Kavir steel complex according to the Bazel convention and RCRA

Introduction: Requiring industries for implementing industrial waste management programs and planning for proper waste disposal is essential in order to achieve sustainable development. Therefore, industrial waste management program was done in Kavir Steel Complex, in Aran va Bidgol region to identify and classify industrial waste and also to present solutions for improving waste management. In this complex, production process is hot rolling steel and the product is rebar. Material and Method: The preset study was conducted in Kavir Steel Complex. Following survey of production process and sources of waste, the type and volume of produced waste were identified and measured during 3 months. Then, the classification of wastes was done according to the Bazel Convention and Resource Conservation and Recovery Act (RCRA), and finally new industrial & health solid waste management program was presented. Result: Considering the volume, industrial waste of production process in Kavir Steel Complex was between 130 to 180 grams per each ton of rebar. Main industrial waste included oxide of steel billet, industrial sludge, used oil and lubricant which were classified according to the RCRA: 8 materials with T code, 1 with C code, 5 with I code and 3 materials with C code. Conclusion: The results revealed that the most amount of industrial waste in Kavir Steel Complex is the waste of steel billet and industrial sludge, and more than 90% of Kavir steel industrial waste were reused and recycled inside or outside of this complex. It is recommended that used oil to be transport and maintain in the safe containers

Arsenic Oxidation Using UV-Activated Persulfate in Aqueous Solutions: Optimization Using Response Surface Methodology Based on Box-Bencken Design

Introduction: The use of arsenic contaminated water can cause a variety of adverse health effects in humans. Therefore, it is essential to seek out a method to remove arsenic more efficiently. This study examined the amount of arsenic oxidation by response surface methodology (RSM) based on Box-Bencken design. Materials and Methods: In this study, oxidizing arsenite to arsenate was performed by activation of persulfate with UV and the optimal conditions determined using the RSM based on Box-Bencken design to evaluate the effects of independent variables on the response (arsenite oxidation efficiency) performance and to predict the best response rate. In this study, the effects of different parameters such as pH (3-11), concentration of persulfate (4-14 mM), and initial concentration of arsenic (0.1-0.9 mg/l) on process efficiency were investigated. The number of tests in this study was 45, and the oxidation rate was measured using the UV visible spectrophotometer (DR 6000) and the molybdate colorimetric method. Results: Increasing the concentration of arsenic increased oxidation. However, with increasing pH, the oxidation rate decreased and the highest oxidation rate at all concentrations was observed at pH 3. The value higher than R2 (0.934) indicated that the oxidation of arsenic (v) could be determined by this model. Conclusion: Arsenite is a highly toxic metal that is difficult to remove by conventional treatment methods, but a pre-treatment phase can convert arsenite into arsenate and facilitate the removal process. In this study, the use of UV-activated persulfate increased the efficiency of arsenic oxidation to 96%

Survey the frequency and type of Fungal Contaminants in Animal Feed of Yazd Dairy Cattles

Introduction About 500,000 species of fungi have been realized up to now. There are abundant fungi in air, soil and our environment. So the growth of them increases in the presence of air moisture and appropriate temperature. However saprophytic fungi have a wide distribution in nature, they are responsible for decomposition of organic materials and playing an important role in the biogeochemical cycles of major nutrients. Some saprophytes are toxic that contaminate human foods and animal feeds by production of mycotoxins. Aflatoxins are the most common and dangerous mycotoxins produced by few species of Aspergillus and penicillium. This group of mycotoxin has disorder and risks, including the induction of liver cancer. They are mutagenic and teratogenic. Aflatoxin B1, B2, G1 and G2, which are naturally produced by several toxic fungi, may contaminate a wide range of dairy animal feeds resulted severe economic loss of cattle meat. Since Aflatoxin B1 and B2 can be transmitted via mammalian’s milk and cheese in form of synthetic Aflatoxin M1 and M2 to human consumers, cause significant health problems. Therefore contamination of animal feed with common toxic airborne saprophytic fungi is a major concern of health officials. Wheat, barley, corn, soybean and other animal feeds may be contaminated with toxic fungi during implantation, harvesting and storage. There are many dairy and livestock centers in Yazd that prepare milk and dairy products for Yazd and neighboring provinces. The aim of current study was to evaluate the amount and type of fungal contaminates of dairy feeds in Yazd dairies. Materials and methods This cross-sectional descriptive study was conducted in the summer of 2012 on 23 dairies in Yazd. Samples of different animal feeds including concentrates, wheat straw, hay, corn, silage corn, soybean and canola as well as waste of bread, were randomly selected from their bulks. The temperature and humidity of feed storage were recorded by using thermometer and portable hygrometer at the time of sampling. Samples were transferred to medical mycology laboratory in paramedical school by sterile containers. Samples were cultured on Sab ouraud dextrose agar plates based on standard method. Isolated fungal colonies were firstly enumerated and identified using macroscopic and microscopic characteristics for determination of their genus and species of saprophytic and toxic fungi. The suspected fungi with definitive diagnosis by the use of the men tioned methods were then identified by performing slide culture by Riddle method. For the detection of aflatoxin producer species UV radiation was used. Results were analyzed statistically by Chi-square and Mann-Whitney test using SPSS 16 software. Results and Discussion Saprophytic hyphomycets including Cladosporium, Alternation Penicilium, Verticillium, Aspergillus, Penicillium species and yeast were the most prevalent isolated fungi from cattle feeds in current study. Bread waste showed maximum contamination with opportunistic fungi such as Mucor and Rhizopus species, other saprophyte moulds and yeasts. Wheat straw had the highest contamination of aflatoxin-producing toxic fungi particularly Aspergillus flavus. Silage and concentrate were ranked as highest average contamination with 42600 and 40600 CFU/g, respectively in present study. There was seen a significant relationship between the average humidity of the environment of open and covered storage of feed with frequency of isolated fungal species (P< 0.001). In indoor environments, the humidity was higher than outdoors, and this is one of the factors effecting the increase aggregation in animal feeds stored in indoor storages. Results of present study were supported by similar previous studies that can be beneficial for the man agement of cattle feeds and public health surveillance particularly in disorders of aflatoxin. Conclusion According to results of present study, there are a high fungal contamination in cattle food with saprophytic and toxigenic fungal spores. Monitoring of animal feed and control of humidity can control the proliferation of micro-organisms in food, eliminate contamination of microorganisms and prevent cross-contaminations. High levels of fungal contamination in intake dairy feed shows that the major source of contamination seems to be in raw materials used for animal feed. With respect to the effect of cattle food contamination especially contamination with Aspergillus flavous on health of cattle and dairy products and the secondary effects on human health, Control of fungal contamination in livestock foods is the best way to prevent aflatoxin contamination in milk and other dairy products, which help to improve the public health

The Antimicrobial Activity of Essential Oil of Zataria Multiflora Boiss and Satureja Khuzestanica and Their Stability

Introduction: Some plants show antimicrobial activity against wide range of microorganism. The aim of this study was to investigate the antimicrobial activity and stability of Zataria multiflora Boiss and Satureja khuzestanica essential oil (EO). Materials and methods: First, these plants (Zataria multiflora Boiss and Satureja khuzestanica) were collected, verified by a botanist, dried, and grinded. Then, hydro-distallation method was used, to obtain EO from each one. Their antimicrobial activity of each EO was evaluated by micro dilution broth method. For stability test, the surfaces (stone, MDF, and steel) were cleaned by 70% ethanol, and then separately incubated with each EO. Then, all were dried, and incubated for 12, 24 and 36 hours at room temperature. After incubation, sampling was done, inoculated on nutrient agar. Finally, the number of colonies grown on each plate was counted. Results: The MIC50 of both EO was 3.1%. But, the MIC90 of Zataria multiflora Boiss EO against all strains was 12.5%, except Escherichia coli which was 6.2%. Also, the MIC90 of Satureja khuzestanica EO against all strains was 12.5%, except Aspergillus niger which was 6.2%. Both EOs had high stability until 36 hours on the stone and steel. In case of MDF, EOs were stable until 24 hours. No significant difference was observed between stability of Zataria multiflora Boiss and Satureja khuzestanica EO. Conclusion: It can be concluded that Zataria multiflora Boiss and Satureja khuzestanica EO have approximately same antimicrobial activity and stability. Since both EOs have high antimicrobial property, they can be applied to remove microbes from different sources