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

ISTRAŽIVANJE INDEKSA ANIZOTROPIJE ČVRSTOĆE ODREĐENOGA EGIPATSKOG UKRASNOG KAMENA

The nature of ornamental stones is anisotropic. The heterogeneous characteristics of the anisotropic rocks vary with direction. The highest to lowest strength ratio is known as the anisotropy strength index (ASI). A thorough investigation of the ASI is necessary to determine the best-directed loads for these rocks. On core specimens that have been bored parallel and perpendicular to the weakness planes, this is estimated using both uniaxial compression and point load testing. For this examination, four different rock types had cores that were drilled conventionally and in line with weakness planes. The research shows that drilling cores to weakness planes at a normal or nearly normal angle (90° to 60°) yields the best, most dependable ASI. According to the current study’s findings, the ASI fluctuates depending on how uniformly the mineral content and texture of rocks are. A suggested way to calculate the ASI and the load point strength is also included. This study reveals that the employment of ornamental stone as is (for example, precipitation position is more robust and reliable than that perpendicular form) is critical in determining the resilience of this type of rock and its spatial implementation (e.g. flooring).Priroda je ukrasnoga kamena anizotropna. Heterogene karakteristike anizotropnih stijena variraju prema smjeru promatranja. Omjer najveće i najmanje čvrstoće poznat je kao indeks anizotropije čvrstoće (ASI). Kod korištenja takvih stijena potrebno je temeljito istraživanje ASI-ja kako bi se utvrdio najbolji smjer opterećenja. To se procjenjuje kod ispitivanja jednoosne tlačne čvrstoće i kod ispitivanja indeksa čvrstoće opterećenjem u točki na jezgrama koje su bušene paralelno i okomito na ravnine oslabljenja. Istraživana su četiri različita tipa stijena čije su jezgre izbušene uobičajeno paralelno s ravninama oslabljenja. Istraživanje pokazuje kako bušenje jezgri do ravnine oslabljenja pod normalnim ili gotovo normalnim kutom (90° do 60°) daje najbolji, najpouzdaniji ASI. Prema rezultatima ovoga istraživanja ASI varira ovisno o ujednačenosti sadržaja minerala i teksture stijene. Također je predložen način izračunavanja ASI-ja koji uključuje indeks čvrstoće opterećenjem u točki. Ovo istraživanje otkriva da je upotreba ukrasnoga kamena po smjeru (na primjer, paralelni je smjer robusniji i pouzdaniji od okomitoga smjera) presudna u određivanju otpornosti ove vrste stijena i u njezinoj prostornoj primjeni (npr. u popločavanju)

A Study of Adiponectin in Children with Diabetes Mellitus

Objectives: Adiponectin is a hormone produced by adipose tissue. It is secreted exclusively by adipocytes and appears to play a role in the pathophysiology of obesity, diabetes mellitus (DM), and its comorbidities. The aim of this study was to assess adiponectin levels in diabetic children with type 1 DM (T1DM) and type 2 DM (T2DM), and to detect its prognostic role in them. Methods: This study was undertaken from April to July 2011 at Minia University Children’s Hospital, Egypt, and included 314 children aged 2–18 years divided into two patient groups. Group I consisted of 164 pre-diagnosed diabetic patients, further subdivided into Group Ia which included 142 patients with T1DM and Group Ib, 22 patients with T2DM; Group 2 included 150 apparently healthy children as a controls; they were age- and sex-matched to the diseased group. Patients were subjected to a thorough history taking, clinical examination, and laboratory investigations including assessment of HbA1c percentages, fasting C-peptide levels, lipid profiles and fasting serum adiponectin levels. Results: Adiponectin levels did not differ significantly between patients with T1DM and T2DM, but it was significantly higher in diabetic patients than in the controls. In T1DM, adiponectin had positive significant correlations with the duration of the disease and waist circumference, while in T2DM, it had a positive significant correlation with the dose of insulin given and negative significant associations with diastolic blood pressure, cholesterol, and C-peptide levels. Conclusion: The results of the study suggest that adiponectin can play a protective role against the metabolic complications of DM

LINEARNO PROGRAMIRANJE KAO ALAT ZA PROJEKTIRANJE SIROVINSKE SMJESE U TVORNICI CEMENTA

This study uses linear programming to develop a methodology for selecting the best raw material mix in an ASCOM cement plant in Egypt. In cement factories, this type adheres to Egyptian chemical composition criteria for raw feed (e.g. 82.5% calcium carbonate, 14.08% silica, 2.5% alumina and 0.92% iron oxide). Furthermore, the model is bound by industry-specific characteristics (e.g. lime saturation factor, silica modulus, alumina modulus and loss of ignition). The results reveal that the model is able to accurately reproduce the mixing of high-quality feed with varying constituent percentages. It is also capable of determining the combining limitations of each ingredient. Furthermore, it demonstrates optimality for additive sourcing short-term planning and capping limestone quality to meet changeable component combinations. Additionally, improving the raw mix reduces limestone feed quality from 51 to 50.6%, resulting in the inclusion of extra limestone reserves.Studija prikazuje metodu linearnoga programiranja uporabljenu sa svrhom odabira najbolje sirovinske smjese u tvornici cementa ASCOM (Egipat). Takva smjesa poštuje egipatske standarde kemijskoga sastava sirovine (npr. 82,5 % kalcijeva karbonata, 14,08 % silikata, 2,5 % aluminijeva oksida, 0,92 % željeznoga oksida). Također, model je uvjetovan industrijskim standardima (npr. faktorom zasićenja vapnom, silikatnim i aluminatnim modulom te gubitkom (oksida) žarenjem). Modelom se mogla točno izračunati visokokvalitetna mješavina različitih (postotnih) komponenti te je dokazan kao optimalan za brz izračun raznih aditiva i postizanje najveće kvalitete vapnenačke sirovine uz doziranje ostalih komponenti. Time je udjel vapnenca bilo moguće smanjiti na 50,6 – 51 %, što je otvorilo put eksploataciji dodatnih rezervi te sirovine

Comparison of the accuracy of two scoring systems in predicting the outcome of organophosphate intoxicated patients admitted to intensive care unit (ICU)

AbstractIntroductionOrganophosphates(OP) are one of the most common causes of poisoning, especially in developing countries, with high morbidity and mortality. As mortality rate of OP poisoning is still high, early diagnosis and appropriate treatment is often life saving. OP is the main cause of poisoning and death in the poison control centre (PCC), Ain Shams University (ASU) in Egypt.ObjectiveTo compare the accuracy of acute physiology and chronic health evaluation score (APACHE IV) and simplified acute physiology score (SAPS II) in the prediction of mortality of patients with organophosphate poisoning (OPP) who required admission to the Intensive Care Unit (ICU) of PCC of ASU between January 1st, 2009 and December 31st, 2009.MethodsA prospective study conducted by collecting data on consecutive patients with acute OPP admitted to the intensive care unit over 12months. Data required to calculate the patients’ predicted mortality by (APACHE) IV and (SAPS) II scoring systems were collected.ResultsNinety patients were recruited in the study with acute OP toxicity. The observed mortality following acute OP toxicity was 13.3% (12 patients). The area under the receiver operator characteristic (ROC) curves of APACHE IV score was better than SAPS II score (0.921±0.054 SE, 0.807±0.078 SE, respectively). APACHE IV and SAPS II scores were significantly higher in the non-survival than in the survival group (P<0.05).ConclusionAPACHE IV and SAPS II scores calculated within the first 24h are good prognostic indicators among patients with acute OP toxicity that required ICU admission with preference to APACHE IV score. APACHE IV and SAPS II scores above 89, 44, respectively within the first 24h are a predictor of poor outcome in patients with acute OP toxicity.RecommendationApplication of APACHE IV and SAPS II scores is a good predictor of high mortality in OP intoxicated patients which helps in proper allocation of resources

Improving social performance through innovative small green businesses: knowledge sharing and green entrepreneurial intention as antecedents

Small businesses are thought to be largely responsible for environmental pollution despite the fact that businesses of all shapes and sizes contribute to this issue. This research explores how important factors such as knowledge sharing (KS) and green entrepreneurial intention (GEI) might help small businesses in Saudi Arabia develop and implement green innovation (GI). It also seeks to determine whether GI is a mediating variable that explains the connection between GEI, KS, and social performance (SP). Accordingly, an online survey was used to collect responses from 284 small entrepreneurs in Saudi Arabia engaged in various types of business activities. The study used partial least squares structural equation modelling for data analysis and hypothesis testing. The results show that GI considerably influences SP while also having a significant link with both GEI and KS. Further, the study reveals that the relationship between GEI, KS, and SP is mediated by GI. The study offers a plethora of suggestions to various stakeholders generally and to Saudi authorities specifically

Antimicrobial resistance among migrants in Europe: a systematic review and meta-analysis

BACKGROUND: Rates of antimicrobial resistance (AMR) are rising globally and there is concern that increased migration is contributing to the burden of antibiotic resistance in Europe. However, the effect of migration on the burden of AMR in Europe has not yet been comprehensively examined. Therefore, we did a systematic review and meta-analysis to identify and synthesise data for AMR carriage or infection in migrants to Europe to examine differences in patterns of AMR across migrant groups and in different settings. METHODS: For this systematic review and meta-analysis, we searched MEDLINE, Embase, PubMed, and Scopus with no language restrictions from Jan 1, 2000, to Jan 18, 2017, for primary data from observational studies reporting antibacterial resistance in common bacterial pathogens among migrants to 21 European Union-15 and European Economic Area countries. To be eligible for inclusion, studies had to report data on carriage or infection with laboratory-confirmed antibiotic-resistant organisms in migrant populations. We extracted data from eligible studies and assessed quality using piloted, standardised forms. We did not examine drug resistance in tuberculosis and excluded articles solely reporting on this parameter. We also excluded articles in which migrant status was determined by ethnicity, country of birth of participants' parents, or was not defined, and articles in which data were not disaggregated by migrant status. Outcomes were carriage of or infection with antibiotic-resistant organisms. We used random-effects models to calculate the pooled prevalence of each outcome. The study protocol is registered with PROSPERO, number CRD42016043681. FINDINGS: We identified 2274 articles, of which 23 observational studies reporting on antibiotic resistance in 2319 migrants were included. The pooled prevalence of any AMR carriage or AMR infection in migrants was 25·4% (95% CI 19·1-31·8; I2 =98%), including meticillin-resistant Staphylococcus aureus (7·8%, 4·8-10·7; I2 =92%) and antibiotic-resistant Gram-negative bacteria (27·2%, 17·6-36·8; I2 =94%). The pooled prevalence of any AMR carriage or infection was higher in refugees and asylum seekers (33·0%, 18·3-47·6; I2 =98%) than in other migrant groups (6·6%, 1·8-11·3; I2 =92%). The pooled prevalence of antibiotic-resistant organisms was slightly higher in high-migrant community settings (33·1%, 11·1-55·1; I2 =96%) than in migrants in hospitals (24·3%, 16·1-32·6; I2 =98%). We did not find evidence of high rates of transmission of AMR from migrant to host populations. INTERPRETATION: Migrants are exposed to conditions favouring the emergence of drug resistance during transit and in host countries in Europe. Increased antibiotic resistance among refugees and asylum seekers and in high-migrant community settings (such as refugee camps and detention facilities) highlights the need for improved living conditions, access to health care, and initiatives to facilitate detection of and appropriate high-quality treatment for antibiotic-resistant infections during transit and in host countries. Protocols for the prevention and control of infection and for antibiotic surveillance need to be integrated in all aspects of health care, which should be accessible for all migrant groups, and should target determinants of AMR before, during, and after migration. FUNDING: UK National Institute for Health Research Imperial Biomedical Research Centre, Imperial College Healthcare Charity, the Wellcome Trust, and UK National Institute for Health Research Health Protection Research Unit in Healthcare-associated Infections and Antimictobial Resistance at Imperial College London

Search for top squark pair production in pp collisions at root s=13 TeV using single lepton events

Peer reviewe

Multiplicity and rapidity dependence of strange hadron production in pp, pPb, and PbPb collisions at the LHC

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