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A 3-dimensional incompressible laminar flow and heat-transfer in a plate-fin heat exchanger (PFHE) where investigated numerically in this article. The influence of mounting a longitudinal vortex generator (LVG) on the offset rectangular-triangular fin (ORT) in the PFHE, on thermal and hydro-dynamic fields are presented. The novelty of this study is by attaching a LVG to an offset strip fin (OSF) surface. The cases of study for the PFHE are established, by using a built-in rectangular winglet pair type RWP longitudinal vortex generator carried out and fitted on this fin to improve the convective heat transfer of the (ORT) fin while minimizing pressure loss. The upper and lower plates are exposed to constant heat flux and the working fluid is air where chosen under a laminar range of RE (600 to 1400). The laminar flow and heat-transfer are governed by continuity, momentum and energy equations. ANSYS FLUENT (2021 R1) is used to get the numerical results, based on the finite volume method. The performance of the VG is assessed for an optimum winglet attack angle (45°), as well as by modifying the geometrical size parameters, namely the height and placement (L) of the RWP LVG. The result shows that the Nusselt number reaches its optimum enhancement values by using a common flow up CFU built-in rectangular winglet pair type RWP VG with a height and entrance length of (h=1.25mm, L=0.5mm), by 22.23% as compared with base case configuration (ORT). Finally, a two more LVG are tested with the optimum conditions of the RWP, which they are a delta winglet pair (DWP) and trapezoidal winglet pair (TWP). In addition, the temperature fields for the primary and secondary flows were shown in contour and streamline diagrams

A plate fin heat exchanger PFHE is a form of compact heat exchanger CHE containing of a block of alternating layers of fins and flat separators known as parting sheets. In this paper, 3-dimensional incompressible laminar flow and heat transfer in a (PFHE) has been investigated numerically. The influences using different fin configurations and the effect of the offset of these fins, on thermal and hydro-dynamic fields are presented. The cases of study for the PFHE are established, by using the fins with different configurations (plain rectangular (PR) and it's offset (OR), plain triangular (PT) and it's offset (OT) which is a novel shape, and a novel combination of a two fin shapes, between rectangular and triangular (ORT)). The upper and lower plates are exposed to a constant heat flux and the working fluid is air where chosen under a laminar range of (Re) number (600 to 1400). The laminar flow and heat transfer is governed by continuity, momentum and energy equations. ANSYS FLUENT (2021 R1) is used to get the numerical results, based on finite volume method. One of the most utilized fins for a PFHE is the offset fin arrangement due to its higher heat change amount, adjustable structure, and enhances flow turbulence and heat transfer coefficient by interrupting the thermal boundary layer. The obtained results of using of the offset configuration increases the Nusselt number by 20.32% and 17.82% for OSF rectangular and OSF triangular, respectively as compared with the with plain configurations, as a result, a significant heat transfer enhancement is observed. And significant increase in the friction-factor is found to be 79.8% and 48.7% for OT and ORT, as compared with the PT. It can be observed that use of the OSF configuration leads to greater f-factor for triangular configuration values. In addition, the temperature fields for the primary and secondary flows were showed in a contour diagram.

This study is a review of recent studies on heat transfer enhancement in plate fin-heat exchangers (PFHE) with plain and offset (OSF) fins. Thermal designing parameters such as the coefficient of heat transfer, Nusselt number, hydraulic diameter, Colburn factor (j), friction factor (f) and Reynold's number of PFHE was presented in this review for both straight and offset types. According to the results, by replacing plain fins into OSF, the pressure increases because of the increasing of f-factor, while there is a significant increase in Nusselt number and then the heat transfer. The j & f factors, are the most essential two parameters of researching the heat exchanger that were represented as functions of Reynolds number and other geometrical parameters. At the same Reynolds number, the J-factor declines and the friction factor f increases as the fin pitch increases for the same fin height and fin thickness.

Most marshes in Iraq face several challenges as aquatic environments, including pollution by various chemical agents and heavy metals. The current study deal with an analysis of the water quality of Dalmaj marsh as one of the closed aquatic environments in the middle parts of Iraq located between latitudes 32ᵒ 05′ to 32ᵒ 23′N and longitudes 45ᵒ 10′ to 45ᵒ 38′ E. The marsh is suffering from a shortage in water supply, especially during the summer. It will lead to a concentration of heavy metals that are washed and transported to the marsh from the surrounding watersheds through surface runoff. This work aims to analyze water and fish samples to assess heavy metals and their accumulated risk in fish tissues based on many indices. The 16 samples of water and nine samples of fish are collected and analyzed for concentration of heavy metals, i.e., Lead (Pb), Chromium (Cr), Nickel (Ni), Cadmium (Cd), Copper (Cu), Zinc (Zn). The water analysis results indicate that Chromium (Cr) only comes below the permissible limit in water. At the same time, the composite heavy metals pollution index (HPI) identified that the water samples are varied from light pollution to malignant pollution. Regarding fish samples, three indices, i.e., BAF, EDI, and HI, are used to test the accumulated concentration of heavy metals in fish tissues and to point out their risk to consumers. The results indicate that Pb and Ni are the more hazardous metals accumulated in many fish samples with increasing fish weight, while hazard index (HI) is an additive index of all tested heavy metals, indicating concern risk from most fish samples. The study recommends testing the marsh water pollution periodically.

تم التطرق في مقدمة البحث الى فاعلية التطور الحاصل في التقنية الالكترونية اذ احدثت تغيرت في طرق تقديم الدروس تمامًا، حيث انعكست على المعلم والمتعلم اذ كان يتعين فيها على المعلم أن يجلس وجهًا لوجه في الفصل ليتفاعل مع الطالب. يمثل الشروع بالفصول الافتراضية الأولى تغيرًا رائدًا في تصور التعليم مما جعل التعلم مسألةً عالميةً. على الرغم من أن استبدال التعلم التقليدي مستحيلًا، إلا أن التعلم الإلكتروني يعد بالفعل مبادرةً بارزةً في ضمن اساليب التدريس التربوي حيث اصبح من الممكن مشاركة الموارد والمواد الدراسية من خلال وسائل عبر الإنترنت مثل المحاضرات المسجلة ورسائل البريد الإلكتروني فضلا عن الدروس الالكترونية وما إلى ذلك، ولا توجد قيود على المكان أو الوقت للطلاب أو المعلمين وتكمن اهمية البحث التعرف على مدى اهمية استخدام التعلم المتزامن وفق بعض البرامج الإلكترونية في تعليم بعض المهارات الأساسية بكره السلة ضمن مخرجات الدرس كون التعلم المتزامن بيئة تعليمية عبر الإنترنت حيث يشارك الطالب بنشاط في تعلمهم الخاص وحيث تتشابه أنشطة التعلم وتوقعاته مع تلك الموجودة في الفصل الدراسي التقليدي. اما مشكلة البحث فذكر الباحثون من كونهم تدريسيين ومن خلال الطلاع على الكثير من البحوث والدراسات ومتابعتهم حول استخدام افضل وسائل التعلم ومدى انعكاسها على تعلم مهارات كرة السلة وجد الباحثون ان استخدام الطرق التقليدية في التعلم اصبحت لا تتلاءم وفق طرق التعلم الحديثة ضمن متطلبات درس التربية الرياضية لذا شرع الباحثون في استخدام وسائل جديديه في التعلم ومنها التعلم المتزامن من اجل احداث تعلم افضل واسرع في تعلم مهارات كرة السلة لطلاب المرحلة المتوسطة (الثاني المتوسط) وفرض الباحثون وجود فرق معنوي ذو دلالة احصائية في تعلم بعض المهارات الاساسية بكرة السلة لدا افراد عينة البحث في نتائج الاختبارات القبلية والبعدية استخدم الباحثون المنهج التجريبي على عينة من طلاب متوسطة السياب للبنين إذ بلغ عددهم (17) طالبا تمثلت بمجموعة تجريبية واحدة. من خلال نتائج البحث توصل الباحثون إلى الاستنتاجات التالية: ان استخدام التعلم المتزامن وفق بعض البرامج الإلكترونية احدثت بيئة تفاعلية حيث انعكست بصورة ايجابية على تعليم المهارات قيد البحث. إن استخدام التعلم المتزامن وفق بعض البرامج الإلكترونية ادى الى حدوث تناغم بين التعلم الالكتروني ومدى استيعاب الطلبة للمادة بحيث انتقل من مخزون الذاكرة الحركية الى حدوث تعليم لدى افراد عينه البحث ضمن مهارتي كرة السلة التوصيات: من خلال الاستنتاجات يوصي الباحث بالاتي: تعميم استخدام التعلم المتزامن وفق بعض البرامج الإلكترونية على المدرس ضمن درس التربية الرياضية لما له من اثر في تعليم المهارات تعزيز تجربة التعلم المتزامن وفق بعض البرامج الإلكترونية لدى عينات مختلفة ومراحل دراسية اخرى العمل على استخدام التعلم المتزامن وفق بعض البرامج الإلكترونية في تعليم مهارات اخرى وفعاليات اخرى

Regular usage and correct administration of secondary prevention drugs for acute coronary syndrome increase the quality of life and survival by up to 80%. This study was conducted to assess the effect of pharmacist educational intervention in improving the adherence of the physicians to guideline-recommended secondary intervention therapy for secondary prevention of acute coronary syndrome and evaluate the clinical benefit of this intervention. A prospective interventional study was conducted in Iraq, Al-Muthanna Governorate, Al-Hussein Teaching Hospital during the period from October 2021 to March 2022. A convenient sampling method was adapted to enrol the participants in the current study which included two groups including the intervention and control group. In the intervention group, the researcher sought to use an educational program, mediated by clinical pharmacists, to improve physician adherence to secondary prevention of acute coronary syndrome in hospitalized patients at discharge. There was no significant difference between the study groups at the first visit after discharge regarding the prescription of aspirin, ACEI, B blocker, or clopidogrel/ticagrelor while there was a significant difference at the end of follow up.

Purpose: Describe patient characteristics, pregnancy outcomes, and infant outcomes among pregnant patients and their linked infants in the novel Maternal Outcomes Masterset (MOM). Methods: We used closed claims within the MOM data to identify publicly and privately-insured patients at first record of pregnancy 1/1/2018-12/1/2021 with ≥180 days baseline enrollment. We described characteristics during baseline and follow-up (until an observed pregnancy endpoint, disenrollment, or 42-week maximum). We described maternal and infant characteristics overall and by infant linkage. Results: Among 1,438,861 pregnant patients meeting the study criteria, the most common pregnancy endpoint recorded was live birth (42%) followed by spontaneous abortion (14%). Among 602,721 patients with a live birth, 99% had a week-specific gestational age recorded and 35% had at least one linked infant. Patients with infant linkage and sufficient follow-up (N=155,621) had similar baseline comorbidities, pregnancy complications, and gestational age at delivery versus those without any linkage. However, more patients with linkage had commercial coverage (70% vs 31%), and were therefore older (50% vs 31% aged ≥30 years) and more likely to have unknown race (57% vs 34%). Conclusions: In this large sample of pregnant patients, maternal and infant characteristics generally align with national statistics, providing confidence in the use of this novel data source for pregnancy research. Further, confirmation that the subset of patients with infant linkage is similar to the overall pregnancy cohort provides assurance that this subset can be considered representative.

The evaluation of structural safety must be taken after each earthquake. The importance losses of life and materials carries the significance of the works in the field of earthquake engineering. The purpose of this study was to optimize and evaluate the earthquake resistance of bridge piers by adopting different cross-section forms and dimensions for bridge supports under earthquake action. Two methods of seismic design were used in the optimization and evaluation process. These methods were demand to capacity ratio (DCR) and yielding point. The results of demand to capacity ratio shown that the values of DCR for all piers forms models were increased when the dimension of pier cross section were increased and the values of DCR became less than 1.0, indicating that the increasing in dimensions leading to rise the capacity of bridge supports to carry the earthquake loads in transverse and longitudinal direction. Comparing with models, solid wall pier form had the lower value of DCR, indicating that solid wall piers were suitable in the design of bridge supports to resist the lateral loads of earthquake and it has enough stiffness and capacity under earthquake action. The results of performance points shown that the yielding points were increased when the dimensions of piers were increased for all piers form in transverse and longitudinal direction. The maximum values were appeared within support No. 1 and support No. 4. Solid wall form of pier had the higher values of yielding points, meaning that this type of piers form had higher seismic capacity and it will resist the earthquake action more than others piers form. This study recommended that to use third model for each pier form in the design of bridges structures to resist the earthquake load. Also this study was recommended to use solid wall piers as supports in construction of bridge structure within areas had earthquake action.

It has been well understanding that the occurrence of various crack patterns in the building during its construction life (from first time of construction up to finishing) then subjected to super imposed load or during the service life. Cracks developed due to exceeding of stresses more than the allowable strength, wherever happened on building component. This research works used the finite element method as a powerful tool to simulate the behavior of full constructed building with both concrete system and brick bearing wall. Where the adopted numerical procedure allows to the users to predict the response of building elements due to conventional state of loading. one of the most important response features was the cracking phenomenon, where the numerical model shown that its capability to predict the cracking sequence from the first time of initiating. The prediction of full response and behavior of each element and their connection, shown that the precise of factor of safety used by the designer, where the analysis prove that the design load was about 67% from the cracking load, and the ultimate load was about 260% from the design load. That will allow more sustainability and stability for long time deformation. Beside the numerical solution, there was an experimental part of study, where site investigation, it shown that all data recorded was constant values and the building was stable. Actually, with no increasing of loading, the building reach its stable state, and defect will not develop. That basically because of good design within conventional state of loading.

Geomorphological processes pose a risk that deserves attention and planning to avoid that, especially in the section near to east of Tuz bridge. This section of the valley facing a dramatic increase in gravel excavation and sorting of aggregates, consequence led to a change in the pattern of river branches flow from an anabranching river to a single-channel river, which led to a concentration of river discharge during floods. On 9th December 2018, Tuz Bridge was failed due to a heavy rainstorm three days preceding the failure event. The current study aims to conduct a field survey of all the human activities in the study area to assess river changes from remote sensing data the amount of runoff and river peak discharge based on rainfall data using SCS-CN method. In this study, ArcGIS, ArcGIS Earth, Google Earth, and WMS software are incorporated in the data analysis. The revealed results indicate the severe modification of valley morphology and converting the river pattern to flow during flood within a single channel with flow speed exceeded the critical velocity to induce vertical erosion of gravel and sands under the foundations of the bridge and causing the displacement and settlement of the bridge. The study recommends the local administration prevent gravel mining from the river valley at the upstream area of the bridge

The results of linear static analysis explained that the increasing of pier heights was leaded to rise the values of positive bending moment, tensile stresses, and downward vertical deflection. Whereas the compressive stresses and negative bending moment were decreased, indicating that the structural performance of bridge structure representing by stiffness, bearing capacity of structural members, and elasticity will decrease and the bridges structures will be damaged. Therefore, the bridges structures need safe design when using tall piers by adopting high quality materials such as high strength concrete, more steel reinforcement, more prestressed tendons, and increasing of cross section dimensions of girders and piers. The results of modal analysis show that the un-loaded dynamic frequency for three types of bridges models were decreased when the pier heights were increased, indicating that the stiffness of bridges structure was became low with higher pier height. According to response spectra and time history analysis results, the loaded dynamic frequency (vibration state) and dynamic displacement were increased when the pier heights were increased, showing that the bridge of structure will suffer from high vibration when the pier height was high. It can be concluded that from this study, the piers heights have significant effects on the static and dynamic structural performance of bridges structures under traffic loads.

Groundwater is an important resource that can be used for various purposes. Various factors can change the chemistry of the GW, such as the chemical composition of an aquifer as well as the leaching of human waste into groundwater. The study area is a barren land covered by some sabkhas, in addition to some agricultural fields. The study aims to assess groundwater quality for drinking purposes using the Water Quality Index. The groundwater is chemically heterogeneous and has a wide quality range from very poor to excellent. Evaporation appears to be the controlling factor among the other shallow waters, while relatively deep water is related to rock-soil dominance. Rocks, land use and land cover have helped control the groundwater quality. Moreover, the heavy use of fertilizers, pesticides and irrigation, in addition to the presence of sabkhas, contributed to the deterioration of the groundwater quality. The water-rock interaction and evaporation are the dominant mechanisms that are controlling the groundwater quality in the study area.

The objective of this study was to assess the seismic performance of two types of bridges structures under effect of earthquake by using different locations and numbers of piers. The results of D/C ratio showed that simply supported I girder bridge appeared higher structural capacity than continuous box girder bridge which was resisted the seismic demand. Continuous box girder bridge had higher seismic demand and lower structural capacity comparing with simply supported I girder bridge. Commonly, the seismic design for two types of bridges models with increasing of piers numbers was suitable to resist the earthquake action for region type B. The results of non-linear static analysis (pushover method) showed that the increasing of piers numbers had significant effects on the seismic design of bridges structures to increase the displacement capacity, force capacity, and decreasing of seismic demand to reduce the effects of earthquake action on the bridges structural members. The bridge type simply supported I girder had higher capacity in longitudinal direction than continuous box girder bridge. Whereas, for continuous box girder bridge appeared higher capacity in transverse direction than simply supported I girder. The performance points which were based on displacement were decreased with increasing the piers numbers for bridges structures supports.

A Structure of wastewater treatment plant is a facility in which a combination of various processes (e.g., physical, chemical and biological) are used to treat wastewater and remove pollutants. Almost the design of wastewater treatment plant structure include two or more stages of construction, based on the capacity of the plant that its related mainly to the income sewage calculated for the population of the city at that time. Future works including many structures that will increase the capacity of the plant on the same area. That’s will need to connect the new structures to the main system by pipe lines and channel. The objectives of this research are to study the connection process and activation of new structure and old structure of wastewater treatment plant, to provide an advice to the method of connection and carry out that connection experimentally with the engineers supervised that works, and to inspect and record the structural information for six months after complete the connection and starting the works with the future structures. The proving the accuracy of adopted method was done by nondestructive test carried out before and after the connection works. The results of construction and inspection shown that the new constructed concrete appears good compressive strength which is reached to 47.45 MPa that will be factored to increase the durability of concrete that being in touch with sewage.