scholarly journals A Residual Analysis for the Removal of Biological Oxygen Demand through Rotating Biological Contactor

2021 ◽  
Vol 40 (2) ◽  
pp. 459-464
Author(s):  
Muhmammad Rafique Daudpoto ◽  
Mir Ghulam Haider Talpur ◽  
Feroz Shah ◽  
Aijaz Khooharo
Keyword(s):  
Oxygen Demand ◽  
Residual Analysis ◽  
Biological Oxygen Demand ◽  
Coefficient Of Determination ◽  
P Value ◽  
Sample Standard Deviation ◽  
Rotating Biological Contactor ◽  
Residual Plot ◽  
The Individual ◽  
Horizontal Band

Regression is a statistical method that is generally used for forecasting and prediction. It helps us to estimate the relationship between a dependent variable and one or more independent variables. This is the most widely used technique that best approximates the individual data points. It has found numerous successful applications in Engineering, Science, business and other fields. Getting average removal % of Biological Oxygen Demand (BOD5) from greywater through Rotating Biological Contactor (RBC), following experiment was conducted in Sindh University hostels using different parameters such as Hydraulic Retention Time (HRT) i.e. 2 hours (0.42 liter per min), 2.5 hours (0.33 l/min) and 3 hours (0.28 l/min) and multiple number of discs i.e. 40, 42, 44, 46, 48, 50 and 52. Consequences reveal that linear estimate of HRTs and numbers of disc are considerable whereas linear and quadratic estimates of number of discs are highly significant, which evidence the significance of time and discs. However, as p-value is greater than 0.05, hence quadratic estimate of HRT is not significant. By using coefficients of the table the regression equation is Removal = - 79.995 + 6.88 time + 2.90 disc, where the sample standard deviation is 7.151, coefficient of correlation is 0.86 and coefficient of determination is 0.742. Distributions of errors are approximately normal as probability plot of the residuals is approximately linear. Residual analysis shows that against each predicted variable, residuals plot falls approximately in a horizontal band symmetric and centered about the horizontal axis and against predicted y-values. Moreover, Residual plot shows the constant standard deviations and linearity assumptions appear to be met.

Efficiency of Packed Cage RBC System for Treatment of Wastewater Containing Surfactants

2003 ◽  
Vol 38 (4) ◽  
pp. 737-752 ◽  
Author(s):  
Suntud Sirianuntapiboon ◽  
Panthong Srikattanaprom
Keyword(s):  
Retention Time ◽  
Hydraulic Retention Time ◽  
Sodium Dodecyl ◽  
Oxygen Demand ◽  
Biological Oxygen Demand ◽  
Rotating Biological Contactor ◽  
Cosmetic Industry ◽  
Removal Efficiencies ◽  
Triton X ◽  
Industry Wastewater

Abstract The chemical oxygen demand (COD) and five-day biological oxygen demand (BOD5) removal efficiencies of a packed cage rotating biological contactor (RBC) system under a hydraulic retention time (HRT) of 16 h declined from 93.90% to 78.58% and 78.61% and 96.27% to 84.83% and 87.93%, respectively, with an increase of sodium dodecyl sulphate (SDS) and triton X-100 loading from 0.00 to 1.25 mg/m2·d. Reactor no. 1 of the system changed to anaerobic when the system was operated under an HRT of 8 h with surfactant loading of up to 2.55 mg/m2·d. However, reactor no. 2 of the system was aerobic and the dissolved oxygen was higher than 3.00 mg/L. The study showed that this type of packed cage RBC system could be applied for treating the cosmetic industry wastewater with surfactant loading of up to 2.55 mg/m2·d under an HRT of 8 h.

Ecological studies on yeasts in the St. Lawrence River

1971 ◽  
Vol 17 (3) ◽  
pp. 353-357 ◽  
Author(s):  
R. E. Simard ◽  
A. C. Blackwood
Keyword(s):  
Oxygen Demand ◽  
Rhodotorula Glutinis ◽  
Biological Oxygen Demand ◽  
Physical Parameters ◽  
Ecological Studies ◽  
Sewage Pollution ◽  
Metabolic Characteristics ◽  
The Individual ◽  
Temperature Depth ◽  
St Lawrence River

The total numbers of yeasts, bacteria, and coliforms found at five stations in the St. Lawrence River, sampled during a 5-month period in the summer of 1968, were compared to temperature, depth, biological oxygen demand (BOD), dissolved oxygen (DO), and salinity. Averaged data indicate some relationships exist among the biological and physical parameters but examination of the data for the individual samples do not lead to the same conclusions. However, the large increase in numbers of Rhodotorula glutinis (the dominant species of the 'pink yeasts') was found to follow the decrease in bacterial numbers, both total count and coliforms, after the introduction of sewage pollution. The metabolic characteristics of these 'pink yeasts,' allowing them to show such rapid increases in numbers, are not known.

scholarly journals EFISIENSI BAMBU AIR (Equisetum hyemale) SEBAGAI FITOREMEDIATOR KADAR BIOLOGICAL OXYGEN DEMAND PADA LIMBAH CAIR INDUSTRI TAHU DI DESA PREMBUN KECAMATAN TAMBAK KABUPATEN BANYUMAS TAHUN 2015

2015 ◽  
Vol 34 (3) ◽  
pp. 189-194
Author(s):  
Andhyka Septyana Nugraha ◽  
Hari Rudijanto IW
Keyword(s):  
Subsurface Flow ◽  
Oxygen Demand ◽  
Biological Oxygen Demand ◽  
P Value ◽  
Test Design ◽  
Equisetum Hyemale ◽  
Post Test

Industri tahu merupakan salah satu jenis usaha industri rumahan (home industri) yang menghasilkan tahudari bahan kedelai.Desa Prembun Kecamatan Tambak Kabupaten Banyumas terdapat 1 pabrik tahu. Rata-ratalimbah cair yang dihasilkan setelah proses pembuatan tahu sebesar 360 liter/ hari dengan konsentrasi BOD5sebesar 15.611,56 mg/liter. Metode yang digunakan untuk menurunkan beban BOD5 pada limbah tahu adalahmetode Fitoremediator menggunakan tanaman Bambu air (Equisetum hymale) dengan media lahan basah buatanaliran bawah permukaan Subsurface Flow Wetlands. Tujuan penelitian adalah untuk mengetahui efisiensi Bambuair (Equisetum hymale) sebagai fitoremediator terhadap penurunan konsentrasi BOD5. Penelitian ini menggunakanjenis penelitian Pre experiment dengan metode pre and post test design yang bermaksud untuk mengetahui ada atautidak adanya perbedaan antara pemakaian tanaman Bambu air (Equisetum hymale) dengan media (SubsurfaceFlow Wetlands) terhadap penurunan konsentrasi BOD5.Hasil penelitian sebagai berikut debit influent 0,22liter/menit dan debit effluent 0,020 liter/menit, parameter suhu influent 30,20 C dan suhu effluent 26,10 C, parameterpH influent 3,82 dan pH effluent 7,95, parameter BOD5 influent 15.611,56 mg/liter dan BOD5 effluent 1.561,16mg/liter dengan efisiensi penurunan sebesar 89,99%. Hasil analisis statistik menggunakan uji paired t-testmenghasilkan nilai signifikan (P Value) sebesar 0.000, yang artinya nilai sig (P value) α (0.05) sehingga terdapatperbedaan yang signifikan. Kesimpulan dari penelitian ini adalah tanaman Bambu air (Equisetum hymale) denganmedia (Subsurface Flow Wetlands) dapat menurunkan konsentrasi BOD5 dengan nilai penurunan yang signifikan.

Physiological and Hereditary Hyperbilirubinemia in Athletes: Role in Reducing Efficiency and Correction Methodology

2020 ◽  
Vol 5 (5) ◽  
pp. 386-393
Author(s):  
L. M. Gunina ◽  
◽  
Kazys Mylashyus ◽  
Voitenko V. L. ◽  
◽  
...  
Keyword(s):  
Physical Activity ◽  
Functional State ◽  
Oxygen Demand ◽  
Diagnostic Algorithm ◽  
Drug Prevention ◽  
The Body ◽  
Erythrocyte Membranes ◽  
Pharmacological Agents ◽  
Bilirubin Metabolism ◽  
The Individual

Under high-intensity loads, the athlete's bodies take place a number of biochemical reactions and physiological processes that can lead to hyperbilirubinemia. The factors that can initiate the onset of this phenomenon include the syndrome of micro-damage muscle, violation of the integrity of erythrocyte membranes, decreased blood pH, malnutrition and increase oxygen demand of the body. Degree of expression of manifestations of physiological bilirubinemia depends on the level of adaptation of the athlete to the physical activities offered. Hyperbilirubinemia in athletes can be one of the components of the deterioration of the functional state, forming the symptoms of endogenous intoxication. The relevance of this problem in sport lies in the relatively low detection rate of hyperbilirubinemia due to the lack of regular screening studies. However, in drawing up a plan of nutritional- metabolic support for training and competitive activity and recovery measures, must not only the individual reaction of the athlete body to physical activity, but also the severity of shifts in the indicators of bilirubin metabolism and their ratio. The article describes the reasons for the increase in bilirubin levels, which can be caused by both the effect of physical activity and by the presence of pathological processes in athletes. The factors influencing the blood serum’s bilirubin content are also highlighted, which include the state of erythrocyte cell membranes and the rate of hemoglobin destruction, the functional state of the liver, the specifics of physical loads and the use of ergogenic pharmacological agents by athletes. Particular accent has been placed on the illumination of hereditary hyperbilirubinemias, which may have been detected at the stage of selection of athletes. The most common phenomenon is Gilbert's syndrome, which occurs in 2-5% of cases in the general population, is characterized in the clinic by a benign flow and is manifested by episodes of jaundice and an increase in total bilirubin content to moderate values due to indirect. The frequency of detection of hyperbilirubinemias in the population of athletes is 4.68%, among which Gilbert's disease accounts for almost half (48.7%). Conclusion. The work highlighted the pathogenesis and diagnostic algorithm of Gilbert's disease, and also emphasized that its drug prevention and correction in athletes to maintain functional and physical fitness should be carried out taking into account anti-doping rules, which requires upon diagnosis timely receipt of a therapeutic exclusion

The Characteristics of Community Wastewater Biological Treatment Processes in Taiwan

1986 ◽  
Vol 18 (7-8) ◽  
pp. 289-296
Author(s):  
C. F. Ouyang ◽  
T. J. Wan
Keyword(s):  
Biological Treatment ◽  
Wastewater Treatment Plants ◽  
Oxygen Demand ◽  
Field Investigation ◽  
Oxidation Ditch ◽  
Trickling Filter ◽  
Rotating Biological Contactor ◽  
Treatment Processes ◽  
Treatment Characteristics ◽  
Sludge Thickening

This study investigated and compared the treatment characteristics of three different kinds of biological wastewater treatment plants (including rotating biological contactor, trickling filter and oxidation ditch) which are currently operated in Taiwan. The field investigation of this study concentrated on the following items: the performance of biological oxygen demand (BOD) and suspended solids (SS) removal; the sludge yield rate of BOD removal; the settleability of sludge solids; the properties of sludge thickening; the power consumption and land area requirement per unit volume of wastewater. Finally, based on the results of the field investigation, a comparison of the treatment characteristics of the three different biological treatment processes was evaluated.

scholarly journals Effective Chromium Adsorption From Aqueous Solutions and Tannery Wastewater Using Bimetallic Fe/Cu Nanoparticles: Response Surface Methodology and Artificial Neural Network

2021 ◽  
Vol 14 ◽  
pp. 117862212110281
Author(s):  
Ahmed S. Mahmoud ◽  
Nouran Y. Mohamed ◽  
Mohamed K. Mostafa ◽  
Mohamed S. Mahmoud
Keyword(s):  
Response Surface Methodology ◽  
Response Surface ◽  
Industrial Effluent ◽  
Oxygen Demand ◽  
Operating Conditions ◽  
Tannery Wastewater ◽  
P Value ◽  
Cu Nanoparticles ◽  
Artificial Neural ◽  
Cr Removal

Tannery industrial effluent is one of the most difficult wastewater types since it contains a huge concentration of organic, oil, and chrome (Cr). This study successfully prepared and applied bimetallic Fe/Cu nanoparticles (Fe/Cu NPs) for chrome removal. In the beginning, the Fe/Cu NPs was equilibrated by pure aqueous chrome solution at different operating conditions (lab scale), then the nanomaterial was applied in semi full scale. The operating conditions indicated that Fe/Cu NPs was able to adsorb 68% and 33% of Cr for initial concentrations of 1 and 9 mg/L, respectively. The removal occurred at pH 3 using 0.6 g/L Fe/Cu dose, stirring rate 200 r/min, contact time 20 min, and constant temperature 20 ± 2ºC. Adsorption isotherm proved that the Khan model is the most appropriate model for Cr removal using Fe/Cu NPs with the minimum error sum of 0.199. According to khan, the maximum uptakes was 20.5 mg/g Cr. Kinetic results proved that Pseudo Second Order mechanism with the least possible error of 0.098 indicated that the adsorption mechanism is chemisorption. Response surface methodology (RSM) equation was developed with a significant p-value = 0 to label the relations between Cr removal and different experimental parameters. Artificial neural networks (ANNs) were performed with a structure of 5-4-1 and the achieved results indicated that the effect of the dose is the most dominated variable for Cr removal. Application of Fe/Cu NPs in real tannery wastewater showed its ability to degrade and disinfect organic and biological contaminants in addition to chrome adsorption. The reduction in chemical oxygen demand (COD), biological oxygen demand (BOD), total suspended solids (TSS), total phosphorus (TP), total nitrogen (TN), Cr, hydrogen sulfide (H2S), and oil reached 61.5%, 49.5%, 44.8%, 100%, 38.9%, 96.3%, 88.7%, and 29.4%, respectively.

scholarly journals Satellite-Derived Protein Concentration of Phytoplankton in the Southwestern East/Japan Sea

2021 ◽  
Vol 9 (2) ◽  
pp. 189
Author(s):  
Hyeonji Bae ◽  
Dabin Lee ◽  
Jae Joong Kang ◽  
Jae Hyung Lee ◽  
Naeun Jo ◽  
...  
Keyword(s):  
Protein Concentration ◽  
Japan Sea ◽  
Biological Properties ◽  
Measured Data ◽  
Trophic Levels ◽  
Coefficient Of Determination ◽  
P Value ◽  
Chl A ◽  
Major Factors

The cellular macromolecular contents and energy value of phytoplankton as primary food source determine the growth of higher trophic levels, affecting the balance and sustainability of oceanic food webs. Especially, proteins are more directly linked with basic functions of phytoplankton biosynthesis and cell division and transferred through the food chains. In recent years, the East/Japan Sea (EJS) has been changed dramatically in environmental conditions, such as physical and chemical characteristics, as well as biological properties. Therefore, developing an algorithm to estimate the protein concentration of phytoplankton and monitor their spatiotemporal variations on a broad scale would be invaluable. To derive the protein concentration of phytoplankton in EJS, the new regional algorithm was developed by using multiple linear regression analyses based on field-measured data which were obtained from 2012 to 2018 in the southwestern EJS. The major factors for the protein concentration were identified as chlorophyll-a (Chl-a) and sea surface nitrate (SSN) in the southwestern EJS. The coefficient of determination (r2) between field-measured and algorithm-derived protein concentrations was 0.55, which is rather low but reliable. The satellite-derived estimation generally follows the 1:1 line with the field-measured data, with Pearson’s correlation coefficient, which was 0.40 (p-value < 0.01, n = 135). No remarkable trend in the long-term annual protein concentration of phytoplankton was found in the study area during our observation period. However, some seasonal difference was observed in winter protein concentration between the 2003–2005 and 2017–2019 periods. The algorithm is developed for the regional East/Japan Sea (EJS) and could contribute to long-term monitoring for climate-associated ecosystem changes. For a better understanding of spatiotemporal variation in the protein concentration of phytoplankton in the EJS, this algorithm should be further improved with continuous field surveys.

scholarly journals Adsorption and Photocatalytic Mineralization of Bromophenol Blue Dye with TiO2 Modified with Clinoptilolite/Activated Carbon

Catalysts ◽  
2020 ◽  
Vol 11 (1) ◽  
pp. 7
Author(s):  
Emmanuel Kweinor Tetteh ◽  
Sudesh Rathilal
Keyword(s):  
Activated Carbon ◽  
Photocatalytic Degradation ◽  
Oxygen Demand ◽  
Freundlich Isotherm ◽  
Reaction Rate Constant ◽  
Coefficient Of Determination ◽  
Bromophenol Blue ◽  
Blue Dye ◽  
Order Kinetic ◽  
Co Precipitation

This study presents a hybridized photocatalyst with adsorbate as a promising nanocomposite for photoremediation of wastewater. Photocatalytic degradation of bromophenol blue (BPB) in aqueous solution under UV-irradiation of wavelength 400 nm was carried out with TiO2 doped with activated carbon (A) and clinoptilolite (Z) via the co-precipitation technique. The physiochemical properties of the nanocomposite (A–TiO2 and Z–TiO2) and TiO2 were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), and Fourier-transform infrared (FTIR) spectroscopy. Results of the nanocomposite (A–TiO2 and Z–TiO2) efficiency was compared to that with the TiO2, which demonstrated their adsorption and synergistic effect for the removal of chemical oxygen demand (COD) and color from the wastewater. At an optimal load of 4 g, the photocatalytic degradation activity (Z–TiO2 > A–TiO2 > TiO2) was found favorably by the second-order kinetic model. Consequently, the Langmuir adsorption isotherms favored the nanocomposites (Z–TiO2 > A–TiO2), whereas that of the TiO2 fitted very well on the Freundlich isotherm approach. Z–TiO2 evidently exhibited a high photocatalytic efficacy of decomposition over 80% of BPB (COD) at reaction rate constant (k) and coefficient of determination (R2) values of 5.63 × 10−4 min−1 and 0.989, respectively.

scholarly journals Use of Thromboelastography Platelet Mapping for Assessment of Individual Platelet Response Secondary to Oral Antiplatelet Therapy after Percutaneous Coronary Intervention: An Attempt to Start Personalized Antiplatelet Therapy in India

2021 ◽  
Author(s):  
Suvro Sankha Datta ◽  
Dibyendu De ◽  
Nadeem Afroz Muslim
Keyword(s):  
Percutaneous Coronary Intervention ◽  
Antiplatelet Therapy ◽  
Platelet Reactivity ◽  
Coronary Intervention ◽  
Platelet Inhibition ◽  
P Value ◽  
Platelet Response ◽  
Percutaneous Coronary ◽  
The Individual ◽  
Platelet Functions

AbstractHigh on-treatment platelet reactivity (HPR) with P2Y12 receptor antagonists in patients treated with dual antiplatelet therapy (DAPT) is strongly associated with adverse ischemic events after percutaneous coronary intervention (PCI). This prospective study was conducted to assess individual platelet response and HPR to antiplatelet medications in post-PCI cases by thromboelastography platelet mapping (TEG-PM). Total 82 patients who were on aspirin and on either clopidogrel, prasugrel, or ticagrelor were evaluated. The percentage of platelet inhibition to arachidonic acid (AA) and adenosine disdiphosphate (ADP) was calculated by [100-{(MA ADP/AA–MA Fibrin) / (MA Thrombin–MA Fibrin) × 100}], taking 50% response as cut-off for HPR. HPR to clopidogrel and prasugrel was 14.29 and 12.5%, respectively. No HPR was detected to aspirin and ticagrelor. The mean percentage of platelet inhibition was significantly higher in patients with ticagrelor 82.99, 95% confidence interval (CI) of [77.3, 88.7] as compared with clopidogrel 72.21, 95% CI of [65.3, 79.1] and prasugrel 64.2, 95% CI of [52.5, 75.9] (p-value of 0.041 and 0.003, respectively). Aspirin along with ticagrelor is associated with a higher mean percentage of platelet inhibition, and lower HPR as compared with the usage of aspirin combined with clopidogrel or prasugrel. Additionally, it might also be concluded that TEG-PM could be used effectively to measure the individual platelet functions which would make oral antiplatelet therapy more personalized for cardiac patients.

Safety climate and related factors in rehabilitation nurses of hospitals in Iran

Work ◽  
2021 ◽  
pp. 1-8
Author(s):  
Javad vatani ◽  
Zahra Khanikosarkhizi ◽  
Mohammad Ali Shahabi Rabori ◽  
mohammad khandan ◽  
Mohsen aminizadeh ◽  
...  
Keyword(s):  
Safety Climate ◽  
Cross Sectional Study ◽  
P Value ◽  
Related Factors ◽  
Cross Sectional ◽  
Climate Assessment ◽  
Safety Work ◽  
Significant Difference ◽  
Training Courses ◽  
The Individual

BACKGROUND: Safety climate is a common insight of staff that indicates individuals’ attitudes toward safety and priority of safety at work. OBJECTIVES: Nursing is a risky job where paying attention to safety is crucial. The assessment of the safety climate is one of the methods to measure the safety conditions in this occupation. The aim of this study was to assess the safety climate of rehabilitation nurses working in hospitals in Tehran. METHODS: This is a cross-sectional study which was carried out on 140 rehabilitation nurses selected from all hospitals and clinics in Tehran in 2019. To collect the required data, a two-section questionnaire was used. The first section was related to demographic factors and the second part (22 statements) was to measure the safety climate using nurses’ safety climate assessment questionnaire. The collected data were analyzed by SPSS V16 using independent t-test, ANOVA, Kruskal-Wallis and Mann-Whitney U test at the 5% level. RESULTS: Findings showed that the total mean of safety climate was 3.06±0.56. According to the results, a significant difference was found between the positive and negative satisfaction of nurses with safety climates (P-value = 0.03), communication with nurses (P-value = 0.01) and supervisors’ attitude (P-value = 0.02). Furthermore, a significant difference in safety climate between the individual with the second job and the individual without second could be observed (P-value = 0.01). CONCLUSIONS: The results indicated that the safety climate was not at an acceptable level. Thus, it is essential to introduce safety training courses (e.g. safety, work-rest balance, and so on) and to improve the safety performance at work.

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