Preferred Language
Articles
/
joe-110
A Laboratory Study Attempt of Flow and Energy Dissipation in Stepped Spillways
...Show More Authors

A new laboratory study conducted on stepped spillways in order to investigate their efficiency of dissipating flow energy. All previous study on stepped spillway indicated that the flow energy dissipation decreased as increasing in discharge. Increasing in the step numbers and the spillway slope led to energy dissipation decrease. In this study, an experimental attempt to increase energy dissipation at variable discharges was performed on stepped spillway and that leads to decreasing the cost of initiating the stilling basin or may be ignoring it. Five spillways were constructed from concrete and tested to investigate and compare among them. Three were roughed by gravel with different size for each one, one of them was stepped without any addition, and the last one was stepped with cavitation. The height of stepped spillways was 18 cm with unique numbers of steps (n = 3), and unique downstream slope of stepped face (θ =30⁰) were utilized. The percentage of relative energy dissipation (R.E.D) was increased using rough surface with coarse gravel. When the size of gravel increased, the R.E.D was increased and when using the ratio between heights of gravel to steps of 0.5, the R.E.D was increased to about triple compared with traditional spillways. The R.E.D was decreased when the cavitation on the stepped surface was utilized compared to the stepped spillway without any addition for large discharges and that was inverse for small discharges. Comparing to steps without any addition, the rouged steps with the larger size of gravel maximized the energy dissipation for both small and large discharges. The relative energy dissipation was 26.73 % compared with traditional spillway and 16.73 % compared with stepped spillway without any addition, since the stepped spillways more effective than traditional spillways by 10 %. In general, the R.E.D was decreased when increasing the discharge.

 

View Publication Preview PDF
Quick Preview PDF
Publication Date
Thu Feb 07 2019
Journal Name
Iraqi Journal Of Laser
Design and Comparative Study of a one and Two Stage Blumlein Circuit TEA Nitrogen Laser
...Show More Authors

Two Prototypes of Transversely Excited at atmospheric pressure (TEA) Nitrogen laser systems (One Stage Blumlein Circuit and Two Stage Blumlein Circuit) were fabricated and operated. High voltage power supply with variable operating voltage (0-20 kv) and operating current (1-3A) was built and tested successfully. The gas flow rate of 15 L/ min and 10 L/ min for OSBC and TSBC was used. The performance of the fabricated systems was studied extensively reaching to the optimum operating conditions. The obtained laser output energy for the first system has linear relationship with the applied voltage. The maximum output energy was about (1.14 mJ) with (10.40) ns pulse duration and the half-wave divergence angle was about (0.1455 m rad). In the

... Show More
View Publication Preview PDF
Publication Date
Tue Jul 01 2025
Journal Name
Minerva Dental And Oral Science
Evaluation of the microleakage of new bioactive restorative materials: a comparative in-vitro study
...Show More Authors

View Publication
Scopus Clarivate Crossref
Publication Date
Mon Dec 30 2024
Journal Name
Gsc Biological And Pharmaceutical Sciences
Taxonomic study of a cultivated plant of genus Zanthoxylum l. 1753 (Rutaceae) in Iraq
...Show More Authors

Zanthoxylum L. 1753 belongs to the family Rutaceae. The plant, with its forest green color and with its distinctive fragrance attracted the attention of the study, specially it was an exotic to the environment of Iraq. Zanthoxylum is an exotic plant produced to Iraq and planted in gardens as an ever-green aromatic plant named (BUKHUR HINDI), as it is known among sellers and farmers in Iraq, because of the aromatic smell that emanated from the leaves and resembles Indian incense. The plant adapted to environmental conditions and succeeded in growing and blooming. It was examined and diagnosed for the first time in Iraq as Zanthoxylum beechyanum K. Koch. (Chinese pepper tree). Morphological characteristics and anatomical characteristi

... Show More
View Publication Preview PDF
Crossref
Publication Date
Fri Nov 29 2019
Journal Name
Iraqi Journal Of Physics
A comparison study of the Structural and magnetic properties of pure Ni metal and NiZnMn ferrite
...Show More Authors

The magnetic properties of a pure Nickel metal and Nickel-Zinc-Manganese ferrites having the chemical formula Ni0.1(Zn0.4Mn0.6)0.9Fe2O4 were studied. The phase formation and crystal structure was studied by using x-ray diffraction which confirmed the formation of pure single spinel cubic phase with space group (Fd3m) in the ferrite. The samples microstructure was studied with scanning electron microstructure and EDX. The magnetic properties of the ferrite and nickel metal were characterized by using a laboratory setup with a magnetic field in the range from 0-500 G. The ferrite showed perfect soft spinel phase behavior while the nickel sample showed higher magnetic loss an

... Show More
View Publication Preview PDF
Crossref
Publication Date
Tue Oct 01 2019
Journal Name
Ceramics International
A first-principles study of the electronic, structural, and optical properties of CrN and Mo:CrN clusters
...Show More Authors

View Publication
Scopus (15)
Crossref (15)
Scopus Clarivate Crossref
Publication Date
Tue Feb 09 2016
Journal Name
Advances In Environmental Biology
A study effect Histological changes
...Show More Authors

Publication Date
Wed Jan 01 2014
Journal Name
Journal Of The College Of Languages (jcl)
Politeness: A Socio- Pragmatic Study
...Show More Authors

The most influential theory of ‘Politeness’ was formulated in 1978 and revised in 1987 by Brown and Levinson. ‘Politeness’, which represents the interlocutors’ desire to be pleasant to each other through a positive manner of addressing, was claimed to be a universal phenomenon. The gist of the theory is the intention to mitigate ‘Face’ threats carried by certain ‘Face’ threatening acts towards others.

            ‘Politeness Theory’ is based on the concept that interlocutors have ‘Face’ (i.e., self and public – image) which they consciously project, try to protect and to preserve. The theory holds that various politeness strategies are used to prot

... Show More
View Publication Preview PDF
Publication Date
Sun Jul 17 2022
Journal Name
Al–bahith Al–a'alami
(دراسة تحليلية): ( A field study )
...Show More Authors

The research aimed to identify the effects of the modern of technology on translating the media term from English language to Arabic. and try to identify the use of the impact of foreign media terminologies on the Arabic media term, and to know the effect of the translation process on Arabic media terminologies.

This research is considered an analytical study by using survey study for 111 items and the results for the study as following:

1.High percentage of the (use of foreign terms work to low the level of production) was (68.13%) and average 3.55

2.The percentage of (The multiplicity of translation of the foreign term into Arabic effects on the opinions and cognitive ideas of the Arab researcher and affects the

... Show More
View Publication Preview PDF
Crossref
Publication Date
Thu Jun 15 2017
Journal Name
International Journal Of Computer Applications
Analytical and Numerical Study of the Temperature Distribution for a Solid Sphere subjected to a Uniform Heat Generation
...Show More Authors

View Publication
Crossref (2)
Crossref
Publication Date
Wed Dec 29 2021
Journal Name
Journal Of The College Of Education For Women
Employment and Labor Union Laws in Japan between the 1889 and 1946 Constitutions: A Comparative Study: أفراح محمد علي
...Show More Authors

This research is based on the descriptive and analytical methodology. The importance of studying labor laws and labor unions in Japan between 1889 and 1946 constitutions is because Japan was out of a feudal phase, and had no idea about the factory system and industrialization in their modern sense before the Meiji era. Generally, its labor system used to be mostly familial, and the economic system was based on agriculture. This called for the enactment of legislations and laws appropriate for the coming phase in Meiji era. Thus, this paper examines the role of Meiji government in enacting labor legislations and laws when he came to power in 1896, and his new constitution in 1889 and the civil code of 1896. It further examines the way Mei

... Show More
View Publication Preview PDF
Crossref