bluuebunny/crossref_metadata_2025_split huggingface dataset:
Numerical Prediction of Reservoir Souring under the Effect of Temperature, Ph, and Salinity on the Kinetics of Sulfate-Reducing Bacteria
Authors: Hosseininoosheri Pooneh , Lashgari Hamidreza , Sepehrnoori Kamy 
Published: March 2017

Abstract
This paper presents an improved numerical model to predict the onset of reservoir souring in sea-water injected reservoirs. The model is developed to study the effect of temperature, salinity, and pH on the growth of sulfate-reducing bacteria (SRB), which are responsible for hydrogen sulfate generation. Furthermore, we investigate the influence of the environmental factors on the prediction of reservoir souring.
First, we model the mechanisms involved in reservoir souring and then identify the parameters that have the crucial effects on the prediction. Previous models assumed that the maximum growth rate is independent and represented by a constant value. They also neglected the competition between different types of substrates. Therefore, we introduce a new mathematical model to express the maximum growth rate of SRB as a function of temperature, salinity, and pH in the first-order Monod kinetics equation. Then, we discuss the modeling of the competition between different types of substrates. Finally, we implement the model into a 3D finite difference non-isothermal reservoir simulator.
The new model results are compared to previous model results and validated against experimental data. Next, a comprehensive sensitivity analysis is performed to show the effect of temperature, salinity, and pH on bacterial growth and the prediction of souring in a numerical reservoir (or core) model. Taking the effect of environmental parameters into account shows the deficiency of previous models to estimate the reservoir souring. Previous models underestimate the concentration of hydrogen sulfate generation per mass of biodegraded substrate (H2S generation coefficient). The results suggest that the hydrogen sulfide concentration increases as the reservoir temperature, salinity, and pH reach the optimum temperature, pH, and salinity required for SRB to reach its maximum growth rate.
The present work differs from earlier works by explicitly determining parametric values required for a kinetic model. This model is as an effective approach to accurately predict the concentration of hydrogen sulfide and thus facilitating accurate decisions on remedial actions.
Oilfield Biocide Performance in the Presence of Shale Formation Rock
Authors: Moore Joseph , Massie-Schuh Ella , Doshi Deepak , Schultz Christine , Castillo Catherine , Patel Bhavin , Moore Makensie , Rajan Jana , Ajayi Bolatito 
Published: March 2017

Abstract
Contamination of oil and gas operations by sulfate-reducing prokaryotes acid-producing prokaryotes, and facultative anaerobic prokaryotes can significantly reduce hydrocarbon quality, compromise asset integrity, and cause plugging in the formation. Complete treatment of these contaminants requires the use of biocides capable of retaining efficacy in the extreme conditions common in deep subsurface wells. This study investigates the interactions of several common oil and gas biocides with shale to determine their suitability for use in the downhole environment. Each biocide was submitted to studies analyzing (1) shale's effect on chemical stability and aqueous availability of the biocides, and (2) resulting biocidal efficacy on common facultative anaerobes. The chemical availability study was performed using high performance liquid chromatography, and the comparative biocidal efficacy study was performed using standard microbial viability assays. Due to variances in complexity of hydraulic fracture networks, the degree of adsorption was also measured as a function of shale surface area. The panel of biocides showed a variety of responses to exposure to shale. Surface-active, cationic biocides rapidly associated with shale preferentially over water, significantly reducing the availability of these compounds in the aqueous phase. Accordingly, their efficacy against planktonic bacteria substantially diminished. Across the range of shale types (surface area and reservoir source) tested, all surface-active biocides lost efficacy. Most biocides that rely on electrophilic reactivity (rather than surface activity) for efficacy against microorganisms showed little to no interaction with solid shale, and biocidal potency was not compromised. These results provide guidance for selection of biocides that will remain stable, chemically available, and ultimately efficacious in the extreme conditions of a subsurface shale reservoir.
Injection of CO2 into an Intact Methane Hydrate Reservoir
Authors: Qorbani Khadijeh , Kvamme Bjørn , Kuznetsova Tatiana 
Published: March 2017

Abstract
Storing captured CO2 within the under ground aquifers to reduced CO2 emission could serve the safe long term storage option. However, operation costs a lot. While, injection of CO2 within the natural gas hydrate reservoirs which is associated with CH4 production could compensate the cost of CO2 storage. Besides production of CH4 from natural gas hydrate reservoirs causes the de-stability of gas producing area which leads to land slides and geological hazards in the area. However, as a result of stable CO2 hydrate formation, combining the CO2 storage with CH4 production could hold the structural stability of the production areas. In this work, we used a reactive transport simulator to model injection of CO2 within the intact methane hydrate reservoir. Our model showed the CO2 hydrate formation within the gas hydrate areas.
ROP Optimization and Modeling in Directional Drilling Process
Authors: Wiktorski Ekaterina , Kuznetcov Artem , Sui Dan 
Published: March 2017

Abstract
Drilling optimization is an engineering strategy to drill wells more productively and efficiently. Specific objectives of directional drilling are good hole quality, firm directional control, high angle-build capacity, maximal durability, optimal rate of penetration (ROP) and low non-productive time (NPT). This can be achieved through a perfect combination of well design, mathematical drilling models, drilling data analysis, and applications of new and high techniques.
High ROP in safe and stable drilling conditions is the most valuable optimization objective. Our study mainly focuses on ROP improvement in directional wells. In this paper, three directional control technologies: steerable mud motors, targeted bit speed systems (TBS) and rotary steerable systems (RSS) have been investigated. Average ROPs with implementation of these technologies have been compared by analyzing more than 30 wells drilled in Russia.
When drilling directional wells with a steerable mud motor, the number of sliding intervals has to be increased to achieve higher dogleg severity (DLS). It results in decreased total ROP, an averaged value in sliding and rotating operations. Conventionally, ROP in rotating intervals is roughly estimated to be two times higher than ROP in sliding intervals. From the analysis of several field cases, a model to describe the total ROP has been developed, where the DLS influence is taken into account. It provides useful knowledge for wellbore trajectory design in terms of achieving high ROP.
Nowadays, factors as bit types, tooth-wear and hydraulics, formation characteristics, drilling mud properties and operational conditions, etc. are considered to optimize rotary drilling. However, the influence of wellbore trajectory, inclination and azimuth in particular, is ignored in existing ROP models. In this study, a traditional multi-regression Bourgoyne and Young ROP model has been extended by dogleg severity factor (DLS) to link the wellbore trajectory design to ROP optimization. The proposed empirical model has been applied to several drilling data sets. Calculated ROP values were compared, and the increased accuracy was seen for all cases. This model can be used for wellbore trajectory planning, more precise ROP prediction and optimization, and post-analysis of drilled wells.
Electrical Resistivity Autonomous Inflow Control Device ER-AICD and its Application in Gravel Pack Completions
Authors: Jadhav Nachiket , Zhambrovskii Dmitrii 
Published: March 2017

Abstract
As it becomes necessary to drill long horizontal extended reach wells to reach out for thin oil rim reservoirs, it also has its own challenges. Usage of new technologies and their implementation in terms of cost efficiency and increased reservoir performance is the primary objective. While producing through horizontal wells there is always a possibility of breakthrough of unwanted water or gas compromising the production of oil and to some extent leaving some valuable oil reservers behind. The reason behind this is that the heel of the well produces at higher rate than the toe because toe has to overcome the frictional pressure losses due to increased pressure drop along the horizontal length of the well.
To tackle this problem Inflow Control Device (ICD) was introduced which will delay the early breakthrough of water or gas. There are different designs of ICDs available in the industry which significantly delays the breakthrough. Most ICDs provide flow restriction for the produced fluid to create uniform inflow profile along the entire length of the wellbore. However, due to uncertainties in reservoir properties there might be water or gas inflow through ICD and no existing ICDs can reverse this problem undermining the optimization of oil production.
This paper presents the design of Electrical Resistivity Autonomous Inflow Control Device (ER-AICD) that on a par with creating uniform inflow profile along the wellbore; it opens and closes the valve when there is oil, water or gas inflow correspondingly. The device will work on the principle of electrical resistivity of reservoir fluids, resulting in more flexibility in downhole operations and optimizing oil production as a whole.
Automatic Model Calibration for Drilling Automation
Authors: Aghito Manuel , Bjørkevoll Knut Steinar , Nybø Roar , Eaton Ammon , Hedengren John 
Published: March 2017

Abstract
Physics-based hydraulic models are essential for proceeding to a high level of automation in drilling. Mathematical models can facilitate process understanding and problem detection, and determine appropriate actions in case of mismatch between model and data. Furthermore, calculations may replace measurements where and when the latter are not available, as normally occurs during connections or when instruments or signal transmissions fail. However, advanced hydraulic models rely on a large set of inputs, such as pipe and wellbore geometry, various tuning parameters and fluid properties. The models are therefore time-consuming and difficult to configure in the field, where third-party experts may be needed at each well, to properly initiate the automation system and adjust it during the drilling process. Although the methods described in this paper are relevant to any critical drilling operation, they are applied to Managed Pressure Drilling (MPD) as a widely deployed example of drilling automation. In MPD, hydraulic models predict downhole conditions and determine the requisite choke pressure for automatic adjustment. A new method for automatic configuration of key model parameters simplifies the tedious job of setting up the model and ensures that the automation system remains tuned to the well, even without onsite model tuning expertise.
The proposed scheme is based on a simple method for separating inaccuracies due to co-linearity in frictional pressure losses and static mud weight. The search for optimal correction factors is based on a sequence of small oscillations of pump rate that can be applied during drilling without interrupting the operation. A massively parallel computing architecture improves the speed of the calibration algorithm proportional to the number of available CPU cores. A set of hydraulic model instances runs in parallel, allowing for efficient testing of changes in input signals within ranges of uncertainty. A method for selecting a subset of the best models that more accurately represent a given well is proposed.
Computer simulations demonstrate how the novel calibration scheme allows automatic tuning of the friction factor and density correction factor, giving accurate prediction of the bottom hole pressure (BHP). The tuning scheme is run with a parallel architecture to demonstrate that correct values of unknown configuration parameters can be automatically determined sufficiently fast for real-time drilling control or as an advisory tool.
The deployment of automation systems in drilling is hampered by the need for dedicated expert personnel to maintain systems that could have reduced the personnel needed on the rig. The proposed automated physics-based model tuning contributes to removing this roadblock, aiming at making automation systems a more cost-efficient option for drilling operations.
Survivin Clinical Features in Cervical Cancer
Authors: Rahman Miftakh Nur , Wijaya Chyntia Resti , Novalentina Maria 
Published: March 2017

Cervical cancer is the primary lethal malignancy for women worldwide, but because it develops over time, it would be one of the most preventable types of cancer. Dysregulation of apoptosis in cells plays a critical role in the malignancy development. Survivin is the smallest inhibitor apoptotic protein (IAP) which has an important part in regulating cell division and inhibitor of apoptosis. This review focused on survivin features in cervical cancer from mechanisms of malignancy relationship to human papillomavirus (HPV) infection through E6 oncogenic protein, role as a biomarker in diagnosis, prognosis, staging and prediction of metastasis, and also as a target for therapy. Regulation of survivin divided into two main groups; cell cycle dependent and cell cycle independent pathway to maintain life and death balance. Survivin expression is upregulated by E6 protein simultaneously repressing p53. Thus cancerous cervical tissue developed. Survivin is also upregulated in hypoxia, a common condition in many tumors and increased angiogenesis. Survivin plays a major role in chemotherapy and radiation resistance in many cases of cervical cancer. As a target of therapy, survivin has a promising performance, suggested very specific and no issue of resistance and also reducing resistance to chemo and radiation therapy. The goal of treatment is to lower survivin expression through transcription inhibition, immunotherapy based on cytotoxic T cell (CTL) activity and gene therapy. Keywords: cervical cancer, survivin, HPV E6 oncoprotein, therapy
Awareness and use of insecticide treated bednets (itns) by mother of under-fives in akuku–uno community
Authors: Eferakorho Aghogho 
Published: March 2017

Malaria is endemic in Nigeria and it has a close relationship with poverty. Poverty influences the risk of having malaria. Malaria in children of under-five cannot be controlled when there is lack or poor compliance with various preventive strategies including awareness and use of insecticide treated nets (ITN). The target set when “Roll Back Malaria” (RBM) was launched in 2000, was that about 60% of children younger than 5 years and mothers in Nigeria should have been sleeping under the insecticide treated nets by 2015.
Objectives: This study examined the awareness and use of ITN by mothers of under-five and also identified factors that are associated with use/non-use by mothers of under-five in Akuku-Uno Community of Delta State with a view of assessing levels of attainment of the Abuja Targets for malaria prevention.
Methodology: This study were carried out in four (4) quarters namely: Ugulu, Umuaja, Umutu and Obeiti of Akuku-Uno Community. It employed descriptive survey design using simple random sampling technique and was conducted among 350 mothers of under- five who gave their consent within the period of 4 weeks study. Data was collected using self structured questionnaire using Pearson product moment correlation coefficient with a value of 0.74 at 0.05 level of significance. Analyses were done using SPSS Version 16.
Results: Majority of respondents (96.3%) were aware of ITN. A good number of respondents (87.1%) possess ITN and (96.7%) claim they have the ITN from health centres . The night before the survey,59.7% of respondents slept under ITN while the reasons for non-compliance include don’t have good one 32%, not long 26% and adverse reaction is 42%. Respondents that claimed to have seen ITN was 96% . Those that have good knowledge with regards to malaria were 46% compared to respondents (54%) that have poor knowledge of malaria. Respondents that uses only one method to prevent malaria were 52% . A good number of respondents (91.5%) used ITN. Respondents (40%) mentioned high temperature as symptom of malaria. For challenges faced by respondent in using ITN, 71.4% of mothers faced no challenges and 87.8% of respondents claim to use ITN for protection.
Conclusion: This study showed that many of the mothers and under -five in this malaria endemic area (96.3%) are aware of ITN and 59.7% of them actually slept under the ITN the night before survey. The net must be readily made available to encourage mothers of under- five to use them. Negative perceptions such as rumor of death which was about 9% leading to non compliance should be corrected and mothers be encouraged to use the ITN.
SEED VIABILITY TEST OF COMMERSIAL DATES ON THE MARKET
Authors: Roektiningroem Ekosari , Widhy Purwanti 
Published: March 2017

This research aims to to know the seed viability of the two dates on the market. It has been done from July to November 2014, in the laboratory of Mathematics and Natural Science Faculty, Yogyakarta State University. The type of Dates seeds are Sayer (oval-cilindrical, ±3cm, dark orange brown/more light than another), and Lulu (round, ±2cm, dark maroon reddish /more dark than Sayer’s). Viability test by germination testing; conducted on plastic tray with cotton sheet and fabric covered; fill with 100 grains of seeds. Repeated 4 times. Incubation at room temperature (±30oC). The parameters were seed fresh weight, seed dry weight, seed moisture, germination percentage and germination rate. The results were analyzed by compare mean - independent samples t test of SPSS 18’th. The results showed that the viability of both of Date’s seeds from local’s market (Sayer and Lulu) is high. Sayer’s have better viability than Lulu’s (due to the germination percentage and germination rate). Keywords: date seed, viability test, germination test
SYNTHESIS OF AMYL VANILLIL ETHER AS WARMING AGENT FROM VANILLIN
Authors: Budimarwanti C. , Theresih Karim 
Published: March 2017

Synthesis of amyl vanillyl ether from vanillin was carried out by two different methods, two-steps reaction method and one-step reaction method. In two-steps reaction method beginning with the first stage reduction of vanillin with NaBH4 to obtain vanillyl alcohol. Then, dehydration vanillyl alcohol and amyl alcohol with concentrated sulfuric acid. Synthesized compound were identification by TLC, IR spectroscopy and GCMS. In one step reaction method the vanillyl alcohol as a result of reduction of vanillin with NaBH4 are not isolated in advance, immediately reacted with amyl alcohol to form amyl vanillyl ether compound with concentrated HCl dehydrator. The results of two-steps reaction method showed that the reduction reaction of vanillin with NaBH4 produced vanillyl alcohol. Vanillyl alcohol compound that produced is white powder and yield 41.28%. Vanillyl amyl ether compound could not synthesis by dehydration from vanillyll alcohol from reduction of vanillin and amyl alcohol. Ether compound from dehydration of vanillyl alcohol from reduction of vanillin and amyl alcohol is diamyl ethers. Method one reaction step successfully synthesized amyl vanilil ether compound. Amyl vanilil ether compound that produced is liquid, colorless and yield 86.42%. Keywords: amyl vanillil ether, vanillin, vanillil alcohol, amyl alcohol
SILICA PURIFICATION FORM MERAPI VOLCANO SAND AS PHOTOVOLTAIC RAW MATERIALS
Authors: Sulistiyani Sulistiyani , Priyambodo Erfan , Yogantari Larasti 
Published: March 2017

Purification of silica sand volcanic Mount Merapi has been done, for raw material photovoltaic. Leaching purification process is done using aqua regia solution, H2SO4, and HCl. Purification of silica sand of Mount Merapi as a raw material photovoltaic assumes that photovoltaic technologies that utilize solar energy is quite affordable, do not run out, and clean so that it will provide long term benefits are substantial. Stage purification process through grinding up to size 60 mesh, iron using magnetic separation, leaching of acid and alkaline leaching. Characterization of the samples using XRD and XRF. The result showed that Mount Merapi volcanic sand containing silica is high at 48-50%. XRD characterization results indicate that the silica in sand samples well as silicon dioxide or mineral has amorphous structure. Among aqua regia, H2SO4 and HCl leaching that has the ability to nicest namely the concentration of concentrated HCl and purified silica has a purity of 59%. Keywords: purification, silica, volcano sand
PENGARUH MODEL PEMBELAJARAN INKUIRI TERBIMBING DAN KREATIVITAS TERHADAP KETERAMPILAN PROSES SAINS PADA SISWA SMA
Authors: Fatmi Nuraini , . Sahyar 
Published: March 2017

Penelitian ini bertujuan untuk mengetahui: 1) Perbedaan keterampilan proses sains siswa yang dibelajarkan dengan model inkuiri terbimbing dengan siswa yang dibelajarkan dengan pembelajaran konvensional, 2) Perbedaan keterampilan proses sains pada siswa yang memiliki tingkat kreativitas tinggi dan pada siswa yang memiliki tingkat kreativitas rendah, 3) Interaksi antara kreativitas dengan model pembelajaran inkuiri terbimbing terhadap keterampilan proses sains siswa. Penelitian ini merupakan penelitian quasi eksperimen dengan desain faktorial 2x2. Populasi penelitian adalah seluruh siswa kelas X pada SMAN I Julok semester genap tahun pelajaran 2013/2014. Sampel penelitian terdiri dari dua kelas yang ditentukan dengan cluster sampling diambil dari dua kelas, yaitu siswa kelas X-2 (eksperimen) sebanyak 30 orang dan siswa X-5 (kontrol) sebanyak 30 orang. Instrumen penelitian berupa tes kreativitas dan tes keterampilan proses sains. Hipotesis dianalisis denganbantuan SPSS 17 for windows pada taraf signifikan 0,05. Berdasarkan analisis data dan uji hipotesis yang dilakukan diperoleh bahwa: 1) Terdapat perbedaan keterampilan proses sains antara siswa yang menggunakan model pembelajaran Inkuiri terbimbing dibandingkan dengan siswa yang menggunakan pembelajaran konvensional. 2) Terdapat perbedaan keterampilan proses sains siswa yang memiliki tingkat kreativitas tinggi dengan siswa yang memiliki tingkat kreativitas rendah, dimana siswa memiliki tingkat kreativitas tinggi memperolehketerampilan proses lebih tinggi dibandingkan dengan siswa yang memiliki tingkat kreativitas rendah. 3) Ada interaksi antara kreativitas dengan model pembelajaran inkuiri terbimbing terhadap keterampilan proses sains siswa.