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Tytuł:
Environmental Quality Management through Parshall Flume Aeration Efficiency Modelling
Autorzy:
Hamed, Mohamed Ahmed Reda
Powiązania:
https://bibliotekanauki.pl/articles/2202322.pdf
Data publikacji:
2023
Wydawca:
Polskie Towarzystwo Inżynierii Ekologicznej
Tematy:
aeration efficiency
dissolved oxygen
environmental life sustainability
Parshall flume
water quality
Opis:
The dissolved oxygen content in surface waters is one of the vital indicators for human water quality usage as well as the aquatic plant and animal environmental life sustainability. Parshall flumes are one of the important ejector devices that are successfully used for oxygen requirement satisfying in various irrigation, wastewater, and ecosystems. However, the present study aimed to manage and improve various waterworks aeration efficiency through integrated modeling of experimental and analytical analysis as well as their operation conditional parameters for the Parshall flumes configuration. On the basis of the experiment work data sets run results, the principal component regression (PCR), partial least squares (PLS), and ridge regression (RR) techniques are used to develop the required aeration efficiency prediction models for such aerators by interrelating the impact of Parshall flumes characteristics and configurations, as well as various water flow rates on aeration efficiency. The predictive models developed in the study were statistically compared to the experimental data. The comparison confirms a good reliability and high accuracy. Considering the proposed aeration models, the optimum design of the new Parshall flumes can be successfully facilitated.
Źródło:
Journal of Ecological Engineering; 2023, 24, 2; 124--130
2299-8993
Pojawia się w:
Journal of Ecological Engineering
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Positive integrable solutions for nonlinear integral and differential inclusions of fractional-orders
Autorzy:
Al-Issa, Shorouk
El-Sayed, Ahmed Mohamed Ahmed
Powiązania:
https://bibliotekanauki.pl/articles/746526.pdf
Data publikacji:
2009
Wydawca:
Polskie Towarzystwo Matematyczne
Tematy:
integral inclusion
fractional-calculus
Caratheodory condition
differential inclusion
fixed point theorem
Opis:
In this paper we study the global existence of positive integrable solution for the nonlinear integral inclusion of fractional order \[ x(t) \in p(t) + I^\alpha F_1 (t, I^\beta f_2 (t, x(\varphi(t)))),\quad t \in (0, 1). \] As an application the global existence of the solution for the initial-value problem of the arbitrary (fractional) orders differential inclusion \[ \frac{dx(t)}{dt}\in p(t)+ I^\alphaF_1(t,D^\gammax(t))),\quad \text{a.e.}\ t gt 0 \] will be studied.
Źródło:
Commentationes Mathematicae; 2009, 49, 2
0373-8299
Pojawia się w:
Commentationes Mathematicae
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Optical Properties of Polyvinyl Chloride Doped with DCM dye Thin Films
Autorzy:
Mohamed, Ahmed Namah
Tuhaiwer, Akeel Shaker
Razzaq, Zaid Saud
Powiązania:
https://bibliotekanauki.pl/articles/1192703.pdf
Data publikacji:
2016
Wydawca:
Przedsiębiorstwo Wydawnictw Naukowych Darwin / Scientific Publishing House DARWIN
Tematy:
DCM
optical properties
polyvinyl chloride
thin films
Opis:
Optical properties such as absorption coefficients, refractive indices, and extinction coefficients of pure polyvinyl-chloride (PVC) and DCM laser dye doped with PVC thin films where prepared using casting method have been determined in the range between 190-1100nm. Measurement have been performed in pure and doped (PVC). The direct electronic transition and indirect energy gaps were calculated using the behaver of absorption coefficient with wavelength. The direct energy gap was 3.9e.V for pure PVC and 2e.V for doped PVC, but indirect energy gap was 2.4e.V for pure PVC and 1.1e.V for doped. The phonon energy was 1.05e.V for pure PVC and was 0.55e.V for DCM doped with PVC thin film.
Źródło:
World Scientific News; 2016, 30; 45-56
2392-2192
Pojawia się w:
World Scientific News
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Antecedents of psychological capital: The role of work design
Autorzy:
Sameer, Yomna M.
Mohamed, Ahmed Amin
Mohamad, Mohamad Saad
Powiązania:
https://bibliotekanauki.pl/articles/522078.pdf
Data publikacji:
2019
Wydawca:
Uniwersytet Ekonomiczny w Katowicach
Tematy:
Job characteristics
Psychological capital
Task performance
Opis:
Aim/purpose – Though psychological capital has become a hot topic in the recent years, scholars have given little attention to its antecedents. This study used the job characteristics model (Hackman & Oldham, 1975) as a framework to examine the relationship between the five job characteristics and the four components of psychological capital. Moreover, task performance is examined as an outcome of psychological capital. Design/methodology/approach – Using structural equation modelling, data were obtained from Egyptian professionals (N = 251). The survey included measures of psychological capital and job characteristics as well as task performance, which was rated by employees’ supervisors. Findings – Results indicate that the five job characteristics of skill variety, task significance, job feedback, job identity and job autonomy are positively related to the four components of psychological capital. Moreover, hope, self-efficacy and resilience were positively related to task performance. However, Egyptian employees’ optimism was not found to be related to task performance. Research implications/limitations – Results contribute to a better understanding of what enhances psychological capital in the workplace. Originality/value/contribution – The current study is the first to integrate the theory of work design with the psychological capacities of hope, optimism, resilience and self- -efficacy. Research on the development of psychological capital has been limited to interventions with little or no attention given to macro or organisational factors that could contribute to its enhancement. Moreover, it is the first to link psychological capital to job performance in an Arab country.
Źródło:
Journal of Economics and Management; 2019, 35; 124-149
1732-1948
Pojawia się w:
Journal of Economics and Management
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Rola ultrasonografii w rozpoznawaniu utajonych złamań kości łódeczkowatej
The role of ultrasonography in the diagnosis of occult scaphoid fractures
Autorzy:
Ali, Mohammed
Ali, Mujtaba
Mohamed, Ahmed
Mannan, Syed
Fallahi, Farshid
Powiązania:
https://bibliotekanauki.pl/articles/1032202.pdf
Data publikacji:
2018
Wydawca:
Medical Communications
Tematy:
złamanie kości łódeczkowatej
Opis:
Background: Ultrasonography is widely utilized by emergency physicians and radiologists to diagnose various orthopaedic diseases, including fractures. We aim to derive a definitive estimate of the diagnostic accuracy of ultrasonography in clinically suspected scaphoid fractures. Methods: We undertook a systematic review and meta-analysis of included diagnostic cohort studies that discussed the use of ultrasonography in the diagnosis of occult scaphoid fractures. We searched the National Institute for Health and Care Excellence database using the Healthcare Databases Advanced Search tool. In addition, we utilized the PubMed database to search the Medical Literature Analysis and Retrieval System Online, Excerpta Medica database, Cumulative Index of Nursing and Allied Health and Allied and Complimentary Medicine databases. Studies were included if they discuss the role of ultrasound imaging in the diagnosis of scaphoid fractures based on cortical interruption, radio-carpal effusion and scapho-trapezium-trapezoid effusion. Quality assessment was performed using the methodological index for non-randomized studies scoring system. Results: 6 non-randomized control studies met the inclusion criteria. Collectively, these included 236 patients with a mean age ranging from 18 to 41.2 years. The quality of these articles ranged between moderate and high based on the methodological index for nonrandomized studies score. The mean sensitivity was 88.95% (standard deviation 10.03) and mean specificity was 89.50% (standard deviation 12.21). Conclusion: The current literature reveals high sensitivity and specificity in the use of ultrasonography in scaphoid fracture diagnosis. However, multiple factors including technical differences in ultrasound machines and probes, small sample sizes and variability of subsequent confirmatory tests have created a challenge in determining the ultimate reliability of ultrasonography in the diagnosis of occult scaphoid fractures. Considering these factors and limitations, large-sample and high-quality clinical trials are needed to adequately assess its reliability for this purpose. One stop clinics, in the authors’ opinion, would be an ideal setting for its introduction as well as for future trials.
Wprowadzenie: Ultrasonografia jest szeroko wykorzystywana w medycynie ratunkowej i radiologii do diagnozowania różnych schorzeń narządu ruchu, w tym złamań. Celem pracy jest jednoznaczne ustalenie stopnia dokładności badania ultrasonograficznego w przypadku klinicznego podejrzenia złamania kości łódeczkowatej. Metody: W pracy podjęto się przeglądu systematycznego i metaanalizy wybranych badań kohortowych, które dotyczą wykorzystania ultrasonografii w rozpoznawaniu utajonych złamań kości łódeczkowatej. Przeszukano bazę National Institute for Health and Care Excellence z wykorzystaniem narzędzia wyszukiwania Healthcare Databases Advanced Search. Wykorzystano również bazę PubMed do przeszukania baz danych Medical Literature Analysis and Retrieval System Online, Excerpta Medica, Cumulative Index of Nursing and Allied Health oraz Allied and Complimentary Medicine Database. Do analizy włączano te badania, które dotyczą roli badania ultrasonograficznego w rozpoznawaniu złamań kości łódeczkowatej na podstawie przerwania ciągłości istoty zbitej, wysięku w stawie promieniowo-nadgarstkowym oraz wysięku w stawie łódeczkowato-czworobocznym. Oceny jakości analizowanych prac dokonywano na bazie klasyfikacji punktowej badań nierandomizowanych. Wyniki: Kryteria włączenia spełniło 6 badań porównawczych bez randomizacji. Badania te obejmowały łącznie 236 pacjentów o średniej wieku od 18 lat do 41,2 roku. Jakość artykułów wahała się pomiędzy średnią a wysoką na podstawie wyniku w klasyfikacji punktowej badań nierandomizowanych. Średnia czułość badania w analizowanych pracach wynosiła 88,95% (odchylenie standardowe: 10,03), a średnia swoistość 89,50% (odchylenie standardowe: 12,21). Wnioski: Najnowsze doniesienia literaturowe mówią o wysokiej czułości i swoistości badania ultrasonograficznego w rozpoznawaniu złamania kości łódeczkowatej. Ustalenie wiarygodności badania ultrasonograficznego w rozpoznawaniu utajonych złamań kości łódeczkowatej jest jednak trudne ze względu na liczne czynniki, takie jak różnice techniczne pomiędzy stosowanymi aparatami i głowicami ultrasonograficznymi, niska liczebność badanych prób oraz różnice w typie badania stosowanego do potwierdzenia rozpoznania. Ze względu na te czynniki i ograniczenia do właściwej oceny wiarygodności badania ultrasonograficznego stosowanego do omawianego celu potrzebne są badania kliniczne wysokiej jakości. Według autorów ośrodki kompleksowej diagnostyki typu „one stop clinic” byłyby idealnym miejscem na wprowadzenie badań ultrasonograficznych do diagnostyki złamań kości łódeczkowatej oraz na prowadzenie badań klinicznych w przyszłości.
Źródło:
Journal of Ultrasonography; 2018, 18, 75; 325-331
2451-070X
Pojawia się w:
Journal of Ultrasonography
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Leczenie choroby zwyrodnieniowej stawu biodrowego przy zastosowaniu iniekcji osocza bogatopłytkowego pod kontrolą ultrasonograficzną: systematyczny przegląd piśmiennictwa
The use of ultrasound-guided platelet-rich plasma injections in the treatment of hip osteoarthritis: a systematic review of the literature
Autorzy:
Ali, Mohammed
Mohamed, Ahmed
Elamin Ahmed, Hussam
Malviya, Ajay
Atchia, Ismael
Powiązania:
https://bibliotekanauki.pl/articles/1032150.pdf
Data publikacji:
2018
Wydawca:
Medical Communications
Tematy:
osocze bogatopłytkowe
Opis:
Purpose: This review aims to determine whether ultrasound-guided platelet-rich plasma injection has any role in improving clinical outcomes in patients with hip osteoarthritis. Methods: A search of the National Institute for Health and Care Excellence database using the Healthcare Databases Advanced Search tool was conducted. The PubMed database was also utilised to search the Medical Literature Analysis and Retrieval System Online, Excerpta Medica database, Cumulative Index of Nursing and Allied Health and Allied and Complimentary Medicine databases. The Preferred Reporting Items for Systematic Review and Meta-Analysis methodology guidance was employed and a quality assessment was performed using the Jadad score. Results: Three randomised clinical trials met the inclusion criteria and were included for analysis. All three trials were of good quality based on the Jadad score. A total of 115 patients out of 254 received platelet-rich plasma injections under ultrasound guidance. The platelet-rich plasma recipient group included 61 males and 54 females with an age range from 53 to 71 years. Outcome scores show an improvement of symptoms and function maintained up to 12 months following platelet-rich plasma injection. Conclusions: Literature to date concludes that intra-articular platelet-rich plasma injections of the hip, performed under ultrasound guidance to treat hip osteoarthritis, are well tolerated and potentially efficacious in delivering long-term and clinically significant pain reduction and functional improvement in patients with hip osteoarthritis. Larger future trials including a placebo group are required to further evaluate these promising results. Level of evidence: Level I, a systematic review of level I studies.
Cel: Celem przeglądu jest ustalenie, czy iniekcja osocza bogatopłytkowego pod kontrolą ultrasonograficzną przyczynia się do poprawy wyników klinicznych u pacjentów z chorobą zwyrodnieniową stawu biodrowego. Metody: Przeszukano bazę danych National Institute for Health and Care Excellence przy użyciu narzędzia Healthcare Databases Advanced Search. Wykorzystując bazę danych PubMed, przeszukano również: Medical Literature Analysis and Retrieval System Online, Excerpta Medica, Cumulative Index of Nursing and Allied Health Literature oraz Allied and Complementary Medicine Database. Zastosowano metodologię zgodną z deklaracją Preferred Reporting Items for Systematic Review and Meta-Analysis, a ocenę jakości badań przeprowadzono przy wykorzystaniu skali Jadada. Wyniki: Trzy randomizowane badania kliniczne spełniły kryteria włączenia do przeglądu i zostały uwzględnione w analizie. Na podstawie wyników w skali Jadada stwierdzono, że wszystkie trzy badania odznaczały się wysoką jakością. Łącznie 115 spośród 254 uczestniczących w badaniach pacjentów otrzymało iniekcje z osocza bogatopłytkowego pod kontrolą ultrasonograficzną. Grupa osób leczonych osoczem bogatopłytkowym liczyła 61 mężczyzn i 54 kobiety w przedziale wiekowym od 53 do 71 lat. Wyniki oceny wskazują na zmniejszenie nasilenia objawów i poprawę stanu czynnościowego stawu, które utrzymywały się do 12 miesięcy od iniekcji osocza bogatopłytkowego. Wnioski: Jak wskazuje dostępne piśmiennictwo, iniekcje osocza bogatopłytkowego podawane dostawowo pod kontrolą ultrasonograficzną w leczeniu choroby zwyrodnieniowej stawu biodrowego są dobrze tolerowane i potencjalnie skuteczne pod względem długotrwałego i istotnego klinicznie ograniczania dolegliwości bólowych i poprawy stanu czynnościowego stawu. W celu bardziej szczegółowej oceny tych obiecujących wyników niezbędne są zakrojone na większą skalę badania z uwzględnieniem grupy placebo. Poziom dowodów: Poziom I, systematyczny przegląd badań poziomu I.
Źródło:
Journal of Ultrasonography; 2018, 18, 75; 332-337
2451-070X
Pojawia się w:
Journal of Ultrasonography
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Water-related diseases following flooding in South Asian countries – a healthcare crisis
Autorzy:
Ahmed, Syed Hassan
Shaikh, Taha Gul
Waseem, Summaiyya
Zahid, Maha
Mohamed Ahmed, Khabab Abbasher Hussien
Irfan, Ullah
Hasibuzzaman, Md Al
Powiązania:
https://bibliotekanauki.pl/articles/40554755.pdf
Data publikacji:
2024-03-30
Wydawca:
Uniwersytet Rzeszowski. Wydawnictwo Uniwersytetu Rzeszowskiego
Tematy:
floods
South Asia
vector-borne disease
water-based disease
water-borne disease
water-washed disease
Opis:
Introduction and aim. Industrialization and elevated greenhouse gas emissions pose significant threats to the environment, raising atmospheric carbon dioxide levels and leading to climate change. Climate change may impact human health either directly via increasing extreme weather frequency and altering disease patterns or indirectly via social institutions and disrupted global supply chain resulting in consequences like undernutrition. Material and methods. This review conducted a comprehensive literature search on PubMed, Google Scholar, and Cochrane Library, from inception to September 2022, using relevant keywords. Analysis of the literature. Massive flooding in South Asia is leading to a surge in water-related diseases. Cholera outbreaks have occurred in countries like Pakistan, India, and Bangladesh following floods, and waterborne diseases like typhoid, rotavirus, hepatitis A, and leptospirosis are prevalent in flood-affected regions. Additionally, Cryptosporidium, Campylobacter, Shigella, and Polio outbreaks are reported. Water-scarce diseases, including scabies, impetigo, and cellulitis, are also on the rise in flood-affected areas. Water-based diseases, such as dracunculiasis, schistosomiasis, and Leishmaniasis, pose significant risks. Vector-borne diseases, including malaria, dengue, and Leishmaniasis, are becoming more prevalent due to flooded areas providing breeding grounds for disease vectors like mosquitoes and sandflies. These diseases are now more common in flood-affected regions, affecting millions of people. Conclusion. Urgent measures are needed, including early warning systems, resilient infrastructure, drainage maintenance, and stricter land-use regulations, to reduce the impact of these natural disasters. International cooperation and immediate action at national and global levels are essential to mitigate the health crises caused by flooding and other natural disasters.
Źródło:
European Journal of Clinical and Experimental Medicine; 2024, 22, 1; 232-242
2544-2406
2544-1361
Pojawia się w:
European Journal of Clinical and Experimental Medicine
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Behavior of RC columns strengthened with steel jacket under static axial load
Autorzy:
Ghoneim, Abd Rahman Mujahid Ahmed
Mohamed, Mohamed Mahmoud Ahmed
Haridy, Kader
Ahmed, Hazem
Pyram, Mohmmad
Khalf, Abdu
Powiązania:
https://bibliotekanauki.pl/articles/27312173.pdf
Data publikacji:
2023
Wydawca:
Polska Akademia Nauk. Czasopisma i Monografie PAN
Tematy:
słup żelbetowy
wzmacnianie
utwierdzenie
kątownik stalowy
taśma stalowa
reinforced concrete column
strengthening
confinement
steel angle
steel strip
Opis:
The column is one of the most significant structural elements, which is designed to support mainly the compressive load. Strengthening of existing reinforced concrete columns is required to enhance ductility and increase load capacity to sustain the overload as sometimes there may be a change in use. Ten rectangular concrete columns were constructed and tested. H/b ratio was kept constant and equals 6 for all columns. The aim of this work is to study the behaviour and efficiency of RC columns strengthened with steel jackets subjected to axial load. An experimental study of the behaviour of ten strengthened concrete columns with slenderness ratio (H/b) equals 6 was carried out. Variables such as aspect ratio (t/b), the volume of steel batten plates, and spacing of steel batten plates at centres (S) were considered. The results showed that using this method of strengthening is very effective and an increase in the axial load capacity of the strengthened columns is obtained.
Źródło:
Archives of Civil Engineering; 2023, 69, 2; 367--379
1230-2945
Pojawia się w:
Archives of Civil Engineering
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Using RUSLE and GIS for the soil loss assessment in arid regions: The case of the Ain Sefra catchment in the Ksour Mountains, Algeria
Autorzy:
Melalih, Ahmed
Mazour, Mohamed
Powiązania:
https://bibliotekanauki.pl/articles/1844352.pdf
Data publikacji:
2021
Wydawca:
Instytut Technologiczno-Przyrodniczy
Tematy:
Ain Sefra watershed
Algeria
arid region
GIS
RUSLE
soil erosion
Opis:
The loss of soil quality due to erosion is a global problem, particularly affecting natural resources and agricultural production in Algeria. In this study, the Revised Universal Soil Loss Equation (RUSLE) is applied to estimate the risk of water erosion in the Ain Sefra arid watershed (Algeria). The coupling of this equation with Geographic Information Systems (GIS) allows to assess and map the soil loss rates. The land erosion is influenced by many control variables, such as the topographic factor of the terrain and the length of slope (LS factor), rainfall erosivity (R factor), sensitivity of soil to erosion (K factor), presence of vegetation (C factor) and the antierosion cultivation techniques (P factor). To calculate the average annual soil loss, these five factors were considered and multiplied in the RUSLE Equation. The result shows that the average rate of soil loss is estimated at about 5.2 t·ha–1·y–1 over the whole watershed. This study is the first of its kind in the region and aims to assess the soil loss caused by water erosion processes in this arid zone. Consequently, it is essential to take real intervention measures in these upstream areas in order to combat this scourge, based on priorities ensuring the sustainable management of natural resources in the study area.
Źródło:
Journal of Water and Land Development; 2021, 48; 205-214
1429-7426
2083-4535
Pojawia się w:
Journal of Water and Land Development
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Exploring the key determinants of organizational management
Badanie kluczowych determinantów zarządzania organizacyjnego
Autorzy:
Ahmed, Umair
Alkashami, Mohamed
Powiązania:
https://bibliotekanauki.pl/articles/27315264.pdf
Data publikacji:
2022
Wydawca:
Politechnika Częstochowska
Tematy:
leadership style
employee engagement
organizational behavior
employee activeness
styl przywództwa
zaangażowanie pracowników
zachowania organizacyjne
aktywność pracowników
Opis:
This study aims to investigate the impact of leadership style and employee engagement on the employee activeness and organizational behavior of the petroleum industry in Bahrain. The objectives also show the investigation of mediating role of employee activeness among the links of leadership style, employee engagement and organizational behavior of the petroleum industry in Bahrain. Examining the moderating impact of customer satisfaction among the relationships between employee activeness and organizational behavior is also part of the current study goals. The results exposed that leadership style and employee engagement have a significant association with employee activeness, and leadership style has a significant association with organizational behavior. The findings also indicated that employee activeness significantly mediates the nexus of leadership style, employee engagement and organizational behavior of the petroleum industry in Bahrain. This study has guided the regulators while formulating policies related to the organizational function that enhance organizational performance.
Niniejsze opracowanie ma na celu zbadanie wpływu stylu przywództwa i zaangażowania pracowników na aktywność pracowników i zachowania organizacyjne przemysłu naftowego w Bahrajnie. Cele pokazują również zbadanie pośredniczącej roli aktywności pracowników wśród powiązań stylu przywództwa, zaangażowania pracowników i zachowań organizacyjnych przemysłu naftowego w Bahrajnie. Badanie moderującego wpływu satysfakcji klienta na relacje między aktywnością pracowników a zachowaniami organizacyjnymi jest również częścią obecnych celów badania. Wyniki ujawniły, że styl przywództwa i zaangażowanie pracowników mają istotny związek z aktywnością pracowników, a styl przywództwa ma istotny związek z zachowaniem organizacyjnym. Wyniki wskazują również, że aktywność pracowników znacząco pośredniczy w powiązaniu stylu przywództwa, zaangażowania pracowników i zachowań organizacyjnych przemysłu naftowego w Bahrajnie. Niniejsze badanie kierowało regulatorami podczas formułowania polityk związanych z funkcją organizacyjną, które poprawiają wydajność organizacji.
Źródło:
Polish Journal of Management Studies; 2022, 25, 2; 21--35
2081-7452
Pojawia się w:
Polish Journal of Management Studies
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Alternating Aerobic and Anoxic Conditions to Eliminate Sludge Accumulation in the Oxidation Ditch System
Autorzy:
El-Morsy, Ahmed
Ayoub, Mohamed
Powiązania:
https://bibliotekanauki.pl/articles/24201600.pdf
Data publikacji:
2023
Wydawca:
Polskie Towarzystwo Inżynierii Ekologicznej
Tematy:
activated sludge
denitrification
nitrification
oxidation ditch
sludge accumulation
upgrade
wastewater treatment
Opis:
The purpose of the present study is to investigate the performance of an upgraded oxidation ditch (OD) system, which was designed and implemented to solve the problem of sludge accumulation at the bottom as well as to get the best removal efficiency of total nitrogen (TN). The upgrading concept is based on dividing the operating volume of the upgraded OD to achieve interchanging between aerobic and anoxic circumstances in order to provide simultaneous nitrification and denitrification (SND). The obtained results indicated that the average TN removal efficiency was 60%, which could be obtained due to a highly efficient SND approach. In addition, the better TN removal efficiency corresponds to the lower sludge volume index (SVI), which reflects the efficiency of the upgraded OD in preventing the accumulation of sludge at the bottom. Effluent ammonium-nitrogen (NH4+-N) and nitrate (NO3--N) concentrations corresponding to a minimum SVI of 41.9 mL/g were 8.6 mg/L for NH4+-N and 8.6 mg/L for NO3--N, respectively. Furthermore, the upgraded OD successfully removes 5-day biochemical oxygen demand (BOD5), chemical oxygen demand (COD), and total suspended solids (TSS) below the permissible limit for final effluent of 60, 80, and 50 mg/L respectively.
Źródło:
Journal of Ecological Engineering; 2023, 24, 3; 304--314
2299-8993
Pojawia się w:
Journal of Ecological Engineering
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Applying the Wastewater Quality Index for Assessing the Effluent Quality of Recently Upgraded Meet Abo El-koum Wastewater Treatment Plant
Autorzy:
Ayoub, Mohamed
El-Morsy, Ahmed
Powiązania:
https://bibliotekanauki.pl/articles/1838434.pdf
Data publikacji:
2021
Wydawca:
Polskie Towarzystwo Inżynierii Ekologicznej
Tematy:
assessment
evaluation
multiple linear regression
quality
wastewater
WWTP
wastewater treatment plant
Opis:
The wastewater quality index (WWQI) can be defined as a single value, which reflects the overall wastewater quality related to its input constituent parameters. The major objective of the present study was to investigate the suitability of the effluent quality from Meet Abo El-koum wastewater treatment plant in Egypt for safe disposal based on the wastewater quality index approach. Moreover, statistical analysis was applied to develop a simple model using multiple linear regression (MLR) for accurate prediction of WWQI depending on different wastewater quality parameters. The results indicate good quality of the treated wastewater for safe disposal in general. Moreover, it is apparent that about 17% of the WWQI values reached excellent quality referring to the classification of the WWQI levels. For greater simplicity, a relationship between BOD5 and COD was deduced using linear regression, so that the results of the BOD5 analyses that appear after five days can be skipped. This approximation can be used to calculate WWQI on a specific day given the results of the treated wastewater analyses on that day.
Źródło:
Journal of Ecological Engineering; 2021, 22, 2; 128-133
2299-8993
Pojawia się w:
Journal of Ecological Engineering
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Possibility of Using Golden Shower (Cassia Fistula) and Poinciana (Delonix regia) Seeds Oil as Non-Conventional Feedstocks for the Production of Biodiesel in Egypt
Autorzy:
Algharib, Ahmed Mohamed
Abd El Hakim, Ahmed Fawzy
El-Khamissi, Haitham Ahmed
El-Hamamsy, Sam Mohamed
Powiązania:
https://bibliotekanauki.pl/articles/2027852.pdf
Data publikacji:
2021
Wydawca:
Polskie Towarzystwo Inżynierii Ekologicznej
Tematy:
biodiesel
Cassia fistula
Delonix regia
linoleic acid
Opis:
The tree pods and seeds of Cassia fistula (CF) and Delonix regia (DR) were collected from the Faculty of Agriculture garden at Al-Azhar University in Cairo, Egypt, during the spring season of 2019. The physical and chemical aspects of pods and seeds were examined. The percentage of oil and fatty acid compositions were then investigated. The pod weights ranged from 61.34 g in DR to 89.29 g in CF, with pod lengths ranged from 42.26 cm (DR) to 62.64 cm (CF). InCassia fistula, the seed weight per pod, the number of seeds per pod, and the weight of 100 seeds per pod were 12.29 g, 84, and 17.22 g, respectively; whereas in Delonix regia, they were 11.31 g, 23.5, and 34.25 g. The C. fistula had high levels of chlorophyll a and b, as well as total chlorophyll (1.016, 1.025, and 2.041 mg $g^{-1}$ DW), while D. regia recorded the lowest levels (0.513, 0.228, 0.741 mg $g^{-1}$ DW). The results also showed that the C. fistula leaves were also heavier than the D. regia leaves, weighing 14.96 g and 5.02 g fresh and dry weight for C. fistula and 10.06 g and 3.87 g fresh and dry weight for D. regia, respectively. The seeds of both plants were chemically tested, with percentages of Lipid, Moisture, Protein, Ash, Fibers, and Total Carbohydrates of 2.11, 10.79, 17.10, 4.95, 5.51, and 59.53 percent for Cassia fistula and 2.13, 6.52, 18.75, 0.37, 13.28, and 58.95 percent for Delonix regia, respectively. Eleven fatty acids were found in both plants seeds oil (lauric, myristic, palmitic, palmitoleic, stearic, oleic, eliadic, linoleic, linolenic, gondoic, and behenic acid). A slight variation was noted in linoleic acid, which was the major component of both oils ranging from 52.17 (CF) to 54.77% (DR). The prediction of the iodine values resulted in 97.6 and 98.8 for Cassia fistula and Delonix regia, respectively, which is a promising model for the production of biodiesel in the future.
Źródło:
Journal of Ecological Engineering; 2021, 22, 10; 19-27
2299-8993
Pojawia się w:
Journal of Ecological Engineering
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Response of Chive (Allium Schoenoprasum L.) Plant to Natural Fertilizers
Autorzy:
Algharib, Ahmed Mohamed
El-Gohary, Ahmed Ebrahim
Hendawy, Saber Fayez
Hussein, Mohamed Salah
Powiązania:
https://bibliotekanauki.pl/articles/1955505.pdf
Data publikacji:
2021
Wydawca:
Polskie Towarzystwo Inżynierii Ekologicznej
Tematy:
chive
organic fertilizer
humic acid
compost tea
Opis:
A field experiment was carried out at the Experimental Farm of SEKEM Company in Bilbes, Sharqia Governorate, Egypt during the 2019 season, in order to study the effect of adding compost tea and humic acid on the growth and active ingredient of the chive (Allium schoenoprasum L.) plant. Chive seeds were sown in nursery in August, two months later seedlings were transplanted to permanent soil. The chive plants received two organic fertilizers: the first one was compost tea (0, 100 and 200 ml/L) as main plot, and the second one was humic acid (0, 2 and 4 g/L) as sub plot. The two fertilizers were sprayed twice, 45 and 75 days after sowing. The results revealed that: the applied compost tea significantly increased the growth and yield characteristics as well as oil percentage and yield, compared with untreated plants. The plants treated with compost tea at 200 ml / L produced the maximum mean values of plant height, fresh and dry weights of herb, as well as essential oil yield. However, humic acid at 4 g /L recorded the highest mean values of plant height, fresh and dry weights of herb. On the other hand, humic acid at 2 g/L gave the highest values of essential oil yield. Moreover, the interaction treatments had a significant effect on all traits under study. Thirty compounds of Chive essential oil (EO) were identified by GC-MS analysis, representing from 65.07 to 93.29% of the total EO. The main compounds found were dipropyl disulfide (12.8–35.4%), dipropyl trisulfide (12.9–30.05%), methyl propyl trisulfide (3.80–9.03%) and 1-propenyl propyl disulfide (1.56–10%). The highest amounts of dipropyl disulfide and 1-propenyl propyl disulfide were detected with humic acid at 4 g/L treatment. The treatment of compost tea at 200 ml/L + humic acid at 2 g/L caused the greatest accumulation of dipropyl trisulfide which recorded 30.05%, while the greatest values of methyl propyl trisulfide (9.03%) were recorded as a result of tea compost at 100 ml/L.
Źródło:
Journal of Ecological Engineering; 2021, 22, 8; 200-208
2299-8993
Pojawia się w:
Journal of Ecological Engineering
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Compact Transverse Electric Silicon-on-Insulator Mode Converter for Mode-Division Multiplexer
Autorzy:
Sharaf, Mohamed H.
El-Mashade, Mohamed B.
Emran, Ahmed A.
Powiązania:
https://bibliotekanauki.pl/articles/2055263.pdf
Data publikacji:
2022
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
integrated optics
silicon-on-insulator waveguide
WDM & MDM systems
perturbation theory
integrated optical
devices
hybrid modes
guided waves
Opis:
On-chip optical-interconnect technology emerges as an attractive approach due to its ultra-large bandwidth and ultra-low power consumption. Silicon-on-insulator (SOI) wire waveguides, on the other hand, have been identified to potentially replace copper wires for intra-chip communication. To take advantage of the wide bandwidth of SOI waveguides, wavelengthdivision multiplexing (WDM) has been implemented. However, WDM have inherent drawbacks. Mode-division multiplexing (MDM) is a viable alternative to WDM in MIMO photonic circuits on SOI as it requires only one carrier wavelength to operate. In this vein, mode converters are key components in on-chip MDM systems. The goal of this paper is to introduce a transverse electric mode converter. The suggested device can convert fundamental transverse electric modes to first-order transverse electric ones and vice versa. It is based on small material perturbation which introduces gradual coupling between different modes. This device is very simple and highly compact; the size of which is 3 μm². Mathematical expressions for both the insertion loss and crosstalk are derived and optimized for best performance. In addition, three-dimensional finite-difference time-domain (3D-FDTD) simulations are performed in order to verify the mathematical model of the device. Our numerical results reveal that the proposed device has an insertion loss of 1.2 dB and a crosstalk of 10.1 dB. The device’s insertion loss can be decreased to 0.95 dB by adding tapers to its material perturbation.
Źródło:
International Journal of Electronics and Telecommunications; 2022, 68, 2; 275--280
2300-1933
Pojawia się w:
International Journal of Electronics and Telecommunications
Dostawca treści:
Biblioteka Nauki
Artykuł
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