Experimental research into the effect of some operation factors and rock properties on the rate of penetration

Purpose. The purpose of this research is to investigate the effect of weight on bit (WOB), rotary speed (RPM), and some rock properties on the rate of penetration (ROP). Methods. Four types of rock were collected from different sites in the south of Egypt (Aswan sandstone, Isawya limestone, Assiut limestone, and Minya marble). These tested samples were drilled by diamond core bit using a fixed laboratory diamond drilling machine under conditions (400 and 1200 rpm), and loads from 12 to 220 kg. WOB, ROP, torque (T) and specific energy (SE) were continuously observed during the drilling trials. The effect of these factors on ROP were examined. Water is used as a flushing and cooling medium. Findings. The effect of some operation factors on the penetration rate regarding mineral composition and different rock type was evaluated and the general equation was carried out to predict the suitable operation factor which gives the best penetration Rate. Originality. The effect of some operation factors on the penetration rate regarding mineral composition and different rock type was evaluated and the general equation was carried out to predict the suitable operation factor which gives the best penetration Rate. Practical implications. The Results demonstrated that ROP was inversely proportional to compressive strength (CS), tensile strength (TS), and density. It was also found that Aswan sandstone, Isawya limestone, Assiut limestone, and Minya marble have CS 111.94 MPa, 131.22 MPa, 125.0 MPa, and 502.5 MPa respectively. Was established that ROP was directly proportional to porosity. Increasing ROP in case of Aswan sandstone is associated with increase in porosity – 23.158%, and in case of Assiut limestone and Isawya limestone ROP is also associated with an increase in porosity – 19.9% and 17.93% respectively. Decreasing ROP in case of Minya marble is associated with decrease in porosity – 2.314%. So, we concluded that marble has lower ROP due to its higher CS, TS, and density and lower porosity than other tested rocks.Мета. Вивчення впливу комплексу основних експлуатаційних параметрів і ряду фізико-механічних властивостей порід на швидкість буріння в умовах різних родовищ Південного Єгипту. Методика. Були відібрані 4 типи порід з різних районів на півдні Єгипту (Асуанської піщаник, вапняк Ісав, Ассіутскій вапняк і мармур Міньї). Експериментальні зразки отримано на стаціонарній лабораторній буровій установці з алмазним долотом при швидкостях обертання 400 і 1200 об/хв та при навантаженнях від 12 до 220 кг. Під час експериментів постійно вимірювалися навантаження на долото, частота обертання, крутний момент на долоті й питома енергія, а також досліджувався вплив цих факторів на швидкість буріння. Як розчин для промивання і охолоджуючий агент використовувалася вода. Результати. Встановлено залежності швидкості буріння від навантаження на долото, питомої енергії та частоти обертання і питомої енергії. Виявлено, що для всіх чотирьох типів породи швидкість буріння збільшується з ростом навантаження на долото, в той час як питома енергія зменшується з ростом швидкості буріння. Розроблено ефективний спосіб прогнозування продуктивності бурової установки. Встановлено, що швидкість буріння обернено пропорційна міцності на стиск, міцності на розтягнення й щільності, а також змінюється прямо пропорційно пористості. Визначено, що менша швидкість буріння мармуру пов’язана з великими значеннями міцності на стиск, розтяг і щільність, а також з меншою пористістю у порівнянні з іншими досліджуваними породами. Наукова новизна. Встановлено нові закономірності взаємозв’язку експлуатаційних параметрів буріння з урахуванням різного типу породи (пісковик, вапняк, мармур) та її мінерального складу, а також обґрунтовано головну умову експлуатаційного фактору, який забезпечує оптимальну швидкість буріння. Практична значимість. Отримані результати дозволяють вибирати оптимальні параметри і режими буріння в процесі розвідки умов залягання родовищ Південного Єгипту, їх мінерального вмісту та стратиграфічних особливостей. Результати будуть корисними для проектних організацій, наукових інститутів з геології й розвідки, а також гірничих підприємств.Цель. Изучение влияния комплекса основных эксплуатационных параметров и ряда физико-механических свойств пород на скорость бурения в условиях пород различных месторождений Южного Египта. Методика. Были отобраны 4 типа пород из различных районов на юге Египта (Асуанский песчаник, известняк Исавии, Ассиутский известняк и мрамор Миньи). Экспериментальные образцы получены на стационарной лабораторной буровой установке с алмазным долотом при скоростях вращения 400 и 1200 об/мин и при нагрузках от 12 до 220 кг. Во время экспериментов постоянно измерялись нагрузки на долото, частота вращения, крутящий момент на долоте и удельная энергия, а также и исследовалось влияние этих факторов на скорость бурения. В качестве промывочного раствора и охлаждающего агента использовалась вода. Результаты. Установлены зависимости скорости бурения от нагрузки на долото, удельной энергии и частоты вращения и удельной энергии. Выявлено, что для всех четырех типов породы скорость бурения увеличивается с ростом нагрузки на долото, в то время как удельная энергия уменьшается с ростом скорости бурения. Разработан эффективный способ прогнозирования производительности буровой установки. Установлено, что скорость бурения обратно пропорциональна прочности на сжатие, прочности на растяжение и плотности, а также изменяется прямо пропорционально пористости. Определено, что меньшая скорости бурения мрамора связана с большими значениями прочности на сжатие, растяжение и плотности, а также с меньшей пористостью по сравнению с другими исследуемыми породами. Научная новизна. Получены новые закономерности взаимосвязи эксплуатационных параметров бурения с учетом различного типа породы (песчаник, известняк, мрамор) и ее минерального состава, а также обосновано главное условие эксплуатационного фактора, который обеспечивает оптимальную скорость бурения. Практическая значимость. Полученные результаты позволяют выбирать оптимальные параметры и режимы бурения в процессе разведки условий залегания месторождений Южного Египта, их минерального содержание и стратиграфических особенностей. Результаты будут полезными для проектных организаций, научных институтов по геологии и разведке, а также горных предприятий.Our sincere gratitude for Mining and Metallurgical Engineering Dept. Faculty of Engineering, Assiut, Egypt for invaluable assistance to upgrade and guidance to completed this article

Enhanced recovery protocols versus traditional methods after resection and reanastomosis in gastrointestinal surgery in pediatric patients

Background Enhanced recovery after surgery (ERAS) is a group of changes in perioperative care that represent a fundamental shift from the traditional management of the gastrointestinal (GI) surgical patient.Objective To compare the results of applying enhanced recovery after GI resection in children versus the traditional methods.Patients and methods This prospective study included 60 patients who underwent GI resectional surgery between February 2016 and February 2017 at our institution. The patients were divided into two groups: group A (30 patients) was managed with ERAS protocol and group B (30 patients) was managed with traditional methods. All the patients underwent standard hand-sewn technique of GI resection reanastomosis. The protocol of ERAS included no routine nasogastric tube, early diet advancement, minimization of narcotic analgesics, early ambulation, and physical rehabilitation.Results The most frequent cause of GI resection reanastomosis surgery was intussusception (33.3% in group A and 36.7% in group B). Patients in group A had a significant lower frequencies of postoperative fever (33.3 vs. 66.7%, P<0.01) and chest infection (26.7 vs. 60%, P<0.01). Moreover, group A showed a significant shorter postoperative length of hospital stay (4 ± 1.2 days in group A vs. 7.1 ±2.05 days in group B, P<0.001).Conclusion Adopting ERAS protocol for resectional GI surgery in pediatric patients should be encouraged as it is results in lower incidences of postoperative fever and chest infection and is associated with less postoperative length of hospital stay.Keywords: enhanced recovery after surgery, enteral nutrition, gastrointestinal surgery, length of hospital stay, pediatric surger

Reduction of harvest losses in mango (Mangifera indica L.) fruit using improved harvesting methods

An experiment was conducted in a private orchard, located along the Blue Nile bank at Hantoub, Gezira State during the seasons of 2007 and 2008, to investigate the effect of improved harvesting methods on reducing physical injury during harvesting of mango fruits of selected cultivars viz. Kitchener (Baladi), Alphonso, Timour, Abu Samaka and Gulbeltour. The experimental design was a split plot with three replications. Cultivars were assigned to the main plots and harvesting methods to the subplots. The harvesting methods consisted of a ladder, a modified picking pole (MPP), a straw mattress (SM) and the traditional picking pole (control). The ladder harvesting method resulted in the lowest percentage (4.4%) of physical injury followed by the modified picking pole (16.0%) and the straw mattress (29.5%), while the traditional picking pole resulted in the highest percentage (53.1%) of physical injury. The cultivar Gulbeltour and Abu Samaka showed the highest percentage of physical injury, while Timour showed the lowest. Both the ladder and the modified picking pole harvesting methods took the longest time (44 minutes) to harvest one hundred mango fruits followed by the straw mattress (19 minutes) and then the traditional method (10 minutes). The cultivars Alphonse, Kitchener and Timour required less time to harvest one hundred fruits, while Gulbeltour and Abu Samaka required more time.      أجريت هذه التجربة في مزرعة خاصة للفاكهة على شاطئ النيل الأزرق بحنتوب ، ولاية الجزيرة في موسمي (2007 و2008) بغرض استخدام بعض طرق الحصاد المحسنة لتقليل الأضرار الميكانيكية التي تحدث لثمار المانجو أثناء الحصاد. استخدم في ذلك نظام تصميم القطع المنشقة بثلاثة مكررات، حيث وزعت الأصناف على القطع الرئيسية وطرق الحصاد على القطع المنشقة. استخدمت خمسة أصناف من المانجو وهي (كتشنر، الفونس، تيمور، أبو سمكة وقلب التور). تم حصادها باستخدام طرق الحصاد الآتية: وهي السلم، الجبادة المحسنة ذات الآلة القاطعة وكيس من القماش و فرشة من الخيش مليئة بأوراق المانجو الجافة بالإضافة إلى الطريقة التقليدية (الجبادة). أوضحت النتائج أن السلم أعطى أفضل نتيجة (4.4%) في تقليل نسبة إصابة ثمار المانجو ثم يأتي بعده الجبادة المحسنة (16.0%) وثم الفرشة (29.5%). بينما أعطت الطريقة التقليدية أكبر نسبة إصابة لثمار المانجو (53.1%). الأصناف قلب التور وأبو سمكة أعطت أعلى نسبة إصابة للثمار بينما الصنف تيمور أعطى أقل نسبة إصابة. أما بالنسبة للزمن المستغرق في الحصاد لكل طريقة ، نجد أن الحصاد بالسلم استغرق أطول زمن (45 دقيقة)، تلاه الجبادة المحسنة (44 دقيقة) ثم الفرشة (19 دقيقة) بينما استغرقت الطريقة التقليدية أقل زمن (10 دقائق) في حصاد المائة ثمرة من المانجو. الأصناف الفونس وكتشنر وتيمور استغرقت أقل زمن لحصاد 100 ثمرة بينما استغرقت الأصناف قلب التور وأبو سمكة زمناً أطول لحصاد نفس العدد من الثمار

Measuring N2- Fixation by some Varieties of Groundnut and their Residual Effect on Subsequent Sorghum Crop using 15N Methodology

Five varieties of groundnuts were studied for their exact amount of nitrogen fixation effect on subsequent sorghum crop. The 15N methodology was used with a non-nodulating groundnut isoline as the reference crop. Six months after the groundnut harvest, sorghum was sown to study the presence of any residual N from fixation and/or soils own conserved N. The non-nodulating groundnut as a reference crop could detect N fixation (Ndfa) as amounting to 60% —70% of the crops need, i.e., 20%-30% more than the 40% -50% detected using sesame as the reference crop. The N derived from soil (Ndfs) was reduced from 50%-60% to 30%-40% which is much closer to what the low N (300ppm) Gezira soil can provide. Subsequent sorghum was positively affected by the preceding groundnut varieties but only variety Medani gave significant straw and total biological yields over the non-nodulating isoline. There was, therefore, an indication of residual N represented by the higher parameters recorded for the varieties. Groundnut is thus a good preceding crop for cereals though more research work is needed in the area of biological nitrogen fixation

Ecology and settlement of marine fouling in the Suez Bay, Egypt

This study deals with seasonal variations, natural correlations and similarities of fouling assemblages on exposure panels in the Suez Bay during January 1992 to January 1993. Three main sources of pollutions flow into the bay; industrial waste products, domestic drainage of Suez city and ships' oil and refuse.The fouling assemblages on the test pan els after various periods (1, 2 and 3 months) belonged mainly to the algae (Ulva rigida), polychaetes (Hydroides elegans), Cirripedes (Balanus amphitrite) and amphipods. The fouling at the lst station was relatively more dense than at the 2nd station during the summer and autumn seasons. The lowest productivity was achieved at the 3rd station which was considered less polluted being offshore water. The overall paucity of fouling in the bay is because of the silt covering the submerged surfaces, particularly at the 2nd station, leading to the prevention of the settlements or establishment of fouling organisms. The seasonal changes in the intensity of fouling assemblages on submerged surfaces in seawater seems to be closely related to seasonal variations in water temperature. The great fouling communities on the buoys and long exposure panels showed a remarkable variety of species and density rather than on short term exposures, which were more dense during warmer months

Competitive adsorption of phenolic compounds from aqueous solution using sludge‐based activated carbon.

Preparation of activated carbon from sewage sludge is a promising approach to produce cheap and efficient adsorbent for pollutants removal as well as to dispose of sewage sludge. The first objective of this study was to investigate the physical and chemical properties (BET surface area, ash and elemental content, surface functional groups by Boehm titration and weight loss by thermogravimetric analysis) of the sludge‐based activated carbon (SBAC) so as to give a basic understanding of its structure and to compare to those of two commercial activated carbons, PICA S23 and F22. The second and main objective was to evaluate the performance of SBAC for single and competitive adsorption of four substituted phenols (p‐nitrophenol, p‐chlorophenol, p‐hydroxy benzoic acid and phenol) from their aqueous solutions. The results indicated that, despite moderate micropore and mesopore surface areas, SBAC had remarkable adsorption capacity for phenols, though less than PICA carbons. Uptake of the phenolic compound was found to be dependent on both the porosity and surface chemistry of the carbons. Furthermore, the electronegativity and the hydrophobicity of the adsorbate have significant influence on the adsorption capacity. The Langmuir and Freundlich models were used for the mathematical description of the adsorption equilibrium for single‐solute isotherms. Moreover, the Langmuir–Freundlich model gave satisfactory results for describing multicomponent system isotherms. The capacity of the studied activated carbons to adsorb phenols from a multi‐solute system was in the following order: p‐nitrophenol > p‐chlorophenol > PHBA > phenol

Stylosanthes as a forage and fallow crop. Proceedings of a regional workshop on the use of Stylosanthes in West Africa

This report is divided into seven sections. The first section deals with biology of Stylosanthes and its importance in West Africa and Latin America. The second section presents papers on the screening and evaluation of Stylosanthes germplasm. This includes genetic diversity, genetic resources, species screening, multi-locational testing and evaluation of accessions. The third part discusses the dynamics, nutrient requirements, and pests and diseases of Stylosanthes species. Section four looks at Stylosanthes-based pastures for livestock production. This section examines stylo-based pasture development, stylo as a source of supplementary feeding, development of grazing, crop-livestock farming system, and evaluation of stylo-grass mixtures. The fifth section examines the integration of Stylosanthes into cropping systems. Some of the topics covered under this topic are establishment techniques, development of millet-stylo cropping systems and research approach and methodologies. The sixth section is on seed production of Stylosanthes and the last section discusses the impact of Stylosanthes

Relationship virtual learning environment and student learning experience: What are the mediating variables?

Virtual Learning Environment (VLE) tools as a web based digital technology and software facilitate teaching activities and student learning experience. It is increasingly becoming an innovative way of learning and an essential part of courses in the Higher Education sector. Although the speedy explosion and increased recognition of virtual learning, little is known how VLE diffusion rate and innovative attributes affect module delivery and student learning experience through the mediating role of virtual collaboration. Using an usable response of 209 university students from the online self-administered survey, our results indicates that there are direct and indirect significant relationships between innovative attributes, module virtual collaboration and learning experience. As a result, lecturers should actively encourage and support students to virtually collaborate with each other around key issues related to VLE in order to enhance their learning experience. The senior management teams of the university should equip academic and support staff with VLE for being able to fully use VLE its full capacity

The relationship between water activity and fish spoilage during cold storage : a review

This review paper presents clearer picture about the relationship between spoilage of cold stored fish and water activity. The paper was an attempt of presenting the recent existing information and the latest development in this regard. It covered the relationship between water activity and moisture content, water activity control, spoilage of fish and its different phases and the relationship between the spoilage and water activity. The paper revealed that during the initial period of storage some of the characteristics of the fish product reduce in intensity or are lost and in the later stage bacterial degradation of tissues became evident. The water activity (aw) played an important factor in fish spoilage and the growth of different microorganisms depends on its rate. If the aw reduced to 0.6, the growth of bacteria and moulds can be prevented. The detection of spoilage can be determined by controlling water activity and in the same time can be retarded by reducing the aw of the fish by either drying or freezing to keep the fish in good stage with high nutritional and organoleptic quality. The information presented in this study is very important and can assist in preventing spoilage of fishes and their products particularly when production and processing operations are applied

Synthesis, antimicrobial evaluation and docking studies of new pyrazolone derivatives

Purpose: To synthesize new antimicrobial azo-pyrazolone derivatives III & IV and evaluate their antimicrobial activities using a combination of in vitro and molecular docking studies.Methods: Azopyrazolone compounds were prepared from the reaction of substituted aniline diazonium with ethyl acetoacetate to give azoxobutyric acid derivatives (II) which were then reacted with phenyl hydrazine or hydrazine hydrate. The pyrazolone derivatives (IV) were acetylated with glacial acetic acid to yield new acetylated pyrazolones (V). An agar dilution method was used to demonstrate the  antimicrobial activities of the pyrazolone derivatives and their minimum inhibitory concentration (MIC) values calculated. Molecular docking studies were employed to further evaluate the most active compounds (on the basis of the MICs obtained).Results: The new pyrazolone derivatives showed varying antimicrobial activities (from negligible to strong) against a number of microorganisms. Derivatives IIIb and Vb showed potent activities against Bacillus subtilis, Sarcina lutea, Staphylococcus aureus and Enterococcus faecalis. However, the new compounds did not show antifungal activity. Molecular docking results for compounds IIIb and Vb wereconsistent with their antimicrobial activities and proved that the compounds inhibited glucosamine-6-phosphate synthase.Conclusion: The new dichloropyrazolone compounds IIIa and Vb possess potent antimicrobial activities. These compounds have promising potential for use as new antibacterial agents or as templates for the design of new antimicrobial drugs.Keywords: Azo-pyrazolone, Dichloropyrazolone, Antimicrobial, Molecular dockin