bluuebunny/crossref_metadata_2025_split huggingface dataset:
The HMG-CoA Reductase Inhibitor Activities of Soy Protein Hydrolysates from Papain Hydrolysis
Authors: Hermanto Sandra , Octavio Aldi , Azrifitria Azrifitria , Kusumaningrum Susi 
Published: August 2021

The search for an HMG-CoA reductase inhibitor agent as a safe and inexpensive alternative treatment for hypercholesterolemia has been carried out using soy protein hydrolysates as one of the bioactive peptide sources. This study was conducted to explore the potency of soy protein hydrolysates as an anti hypercholesterolemia agent by an in vitro assay, through the inhibition capacity of the HMG-CoA (3-hydroxy-3-methyl glutaryl-coenzyme A) reductase enzyme as a key component of cholesterol biosynthesis. Sample preparation started with soy protein isolation through acid precipitation and separated by centrifugation. The samples were analyzed the proximate content and hydrolyzed by papain enzyme at concentration 0.2% (w/v), for 0-6 hours and at 37, 50, and 55 oC. The protein hydrolysates were subsequently evaluated for hydrolysis degree (% DH), hydrolysates profile with SDS-PAGE (Sodium Dodecyl Sulphate Polyacrylamide Gel Electrophoresis), and anti-cholesterol assay through HMG-CoA reductase inhibition tests. The sample with the highest inhibition activity was fractionated using gel filtration chromatography (Sephadex G-10) and the molecular weight of fractions was characterized by LCMS QTOF (Liquid Chromatography-Mass Spectrometry Quadrupole Time-of-Flight) for molecular weight determination. The results indicated the optimum hydrolysis conditions of soy protein isolates were obtained at 3 hours incubation, at 50 °C with DH 33.39% and the inhibition value was 95.65% (protein concentration 39.21 μg / mL). LCMS data showed the molecular weight of fractionated peptides were 1514 and 2029 Da. We assumed that both peptides have the same affinity as previous peptides in inhibiting HMG-CoA reductase.
Chemical Sensor for Detection of Lead Levels in Herbal Medicine
Authors: Mulyasuryani Ani , Prananto Yanuar Ponco , Krisnaniningrum Elvian Eka 
Published: August 2021

A new tube type Pb2+ sensor made from two types of mixtures, namely clay-PbI2 and chitosan-PbI2 were prepared. An electromotive force (EMF) with Ag/AgCl as the reference electrode was used as the output signal. The highest performance of the Pb2+ sensor from clay-PbI2 was obtained at Pb2+ solutions in HNO3 and pH 3 with sensor sensitivity of 20.67 mV/decade. The highest performance of the Pb2+ sensor from chitosan-PbI2 was obtained at Pb2+ solutions in demineralized water with sensor sensitivity of 32.49 mV / decade. Application of the two sensors on several commercial herbal samples resulted in an average recovery of 85.62% and 94.10% for sensor from chitosan-PbI2 and clay-PbI2, respectively
Requirements Engineering of Village Innovation Application Using Goal-Oriented Requirements Engineering (GORE)
Authors: Kartiko Condro , Wardhana Ariq Cahya , Saputra Wahyu Andi 
Published: August 2021

The delay in the absorption of village funds from the central government to the village government is due to the village government's difficulty preparing village development innovation programs. The innovation tradition will grow if the cycle of transformation of knowledge and acceptable practices from one village to another, especially villages with similar conditions and problems, can run smoothly. For the process of exchanging knowledge and experiences between villages to run smoothly, it is necessary to codify best practices in a structured, documented, and disseminated manner. This research aims to design an application that functions as a medium for sharing knowledge about the use of village funds through government innovation narratives. The application is expected to become a reference for villages to carry out innovative practices by conducting replication studies and replicating acceptable practices that other villages have done. Therefore, it is necessary to have a system requirements elicitation method that can explore the village's requirements in sharing knowledge so that the resulting system is of high quality and by the objectives of being developed. There are several Goal-Oriented Requirements Engineering (GORE) methods used, such as Knowledge Acquisition in Automated Specification (KAOS) and requirements engineering based on business processes. In this research, the KAOS method was demonstrated as the elicitation activity of a village innovation system. Then the results were stated in the Goal Tree Model (GTM). Model building begins with discussions with the manager of the village innovation program to produce goals. The goals are then broken down into several sub-goals using the KAOS method. The KAOS method is used for the requirements elicitation process resulting in functional and non-functional requirements. This research is the elicitation of the requirement for the village innovation system so that it can demonstrate the initial steps in determining the requirements of the village innovation system before carrying out the design process and the system creation process. The results of this requirement elicitation can be used further in the software engineering process to produce quality and appropriate village innovation applications.
Islam and State: A Study on Al-Mawardi and An-Nabhani’s thought and its Compatibility in Indonesian Context
Authors: Rohman Fathor , Basya M Hilali , Sopa Sopa 
Published: August 2021

Even though study concerning Islam and politics has been conducted by many researchers, few of them investigating about compatibility of Islamic political thoughts, which originated from the classical and medieval periods that have been influencing Islamic political movements and thoughts in Indonesia, with Indonesian context. Thoughts of Imam al-Mawardi (lived in the 12th Century) and Taqiyuddin al-Nabhani (lived in the 20th Century) are some of them that should be mentioned in this regard. Islamic political thoughts of al-Mawardi become the main reference for Sunni Muslims who are majority in Indonesia, while Islamic political thought of al-Nabhani become the main guidance of HTI (Hizbut Tahrir Indonesia) movement of which its members and followers are many in Indonesia. This article investigates about the political thoughts of al-Mawardi and al-Nabhani concerning the relationship between Islam and state as well as their compatibility with Indonesian context. This study uses the library research in which its primary resources are books written by al-Mawardi entitled Al-Ahkam al-Sulthaniyah and al-Nabhani entitled Ad-Daulah al-Islamiyah. By utilizing qualitative content analysis, data were collected and analyzed. This article argues that the Islamic political thought of al-Mawardi has been adopted by majority of Indonesian Sunni Muslims with some adjustments with Indonesian context, so that his thoughts become compatible with the concept of modern nation-state of Indonesia. On the other side, Islamic political thought of al-Nabhani which developed within a spirit of resistance to Western (European) colonialism has been adopted and campaigned by HTI without adjustment with Indonesian context. This causes al-Nabhani’s thought clashes with the concept of modern nation-state of Indonesia.
Application of Machine Learning in Predicting Crude Oil Production Volume
Authors: Innocent Okechukwu Prince 
Published: August 2021

Abstract
The production of oil is of great and immense significance as a source of energy worldwide. The major factors affecting the production volume of oil is classified into two groups namely the geological and the human factor. Each group comprises of factors affecting oilfield production volume. The challenge in this project is to find the variable for the crude oil production volume in an oilfield because there are numerous factors affecting the crude oil production volume in an oilfield. The objective of this paper is to provide a more accurate and efficient solution on how to predict the oil production volume.
Furthermore, Machine Learning algorithm called Multiple Linear Regression was developed using Python programming Language to predict the production volume of oil in an oilfield. The model was developed and fitted to train and test the factors that affect and influence the oil production volume. After a several studies have been made, the affecting factors were provided from the oilfield which would be trained and tested in order to model the relationship between predictor variable and response variable which are the significant affecting factors and the oil production volume respectively. The predictor variables are the startup number of wells, the recovery percent of previous year, the injected water volume of previous year and the oil moisture content of previous year. The predictor variable is the oil production volume.
Moreover, the model was found to possess greater utility in predicting the production volume of oil as it yielded an oil production volume output with an accuracy of 98 percent. The relationship between oil production volume and the affecting factors was observed and drawn to a perfect conclusion.
This model can be of immense value in the oil and gas industry if implemented because of its ability to predict oilfield output more accurately. It is an invaluable and very efficient model for the oilfield manager and oil production manager.
A Comprehensive Review of Recent Advances in the Estimation of Natural Gas Compressibility Factor
Authors: Omobolanle Oluwasegun Cornelious , Akinsete Oluwatoyin Olakunle 
Published: August 2021

Abstract
Accurate prediction of gas compressibility factor is essential for the evaluation of gas reserves, custody transfer and design of surface equipment. Gas compressibility factor (Z) also known as gas deviation factor can be evaluated by experimental measurement, equation of state and empirical correlation. However, these methods have been known to be expensive, complex and of limited accuracy owing to the varying operating conditions and the presence of non-hydrocarbon components in the gas stream. Recently, newer correlations with extensive application over wider range of operating conditions and crude mixtures have been developed. Also, artificial intelligence is now being deployed in the evaluation of gas compressibility factor. There is therefore a need for a holistic understanding of gas compressibility factor vis-a-vis the cause-effect relations of deviation. This paper presents a critical review of current understanding and recent efforts in the estimation of gas deviation factor.
Targeting and Developing the Remaining Pay in an Ageing Field: the Ovhor Field Experience
Authors: Ihwiwhu Christian , Itotoi Ibi-Ada , John Udeme , Obioha Nnamdi , Okoro Precious , Ndubueze Maduabuchi , Bobade Edward , Awujoola Adedeji , Bekibele Oghenerunor , Adesanya Sola 
Published: August 2021

Abstract
Understanding the complexity in the distribution of hydrocarbon in a simple structure with flow baffles and connectivity issues is critical in targeting and developing the remaining pay in a mature asset. Subtle facies changes (heterogeneity) can have drastic impact on reservoir fluids movement, and this can be crucial to identifying sweet spots in mature fields. This study evaluated selected reservoirs in Ovhor Field, Niger Delta, Nigeria with the objective of optimising production from the field by targeting undeveloped oil reserves or bypassed pay and gaining an improved understanding of the selected reservoirs to increase the company's reserves limits.
The task at the Ovhor field, is complicated by poor stratigraphic seismic resolution over the field. 3-D geological (Sedimentology and stratigraphy) interpretation, Quantitative interpretation results and proper understanding of production data have been used in recognizing flow baffles and undeveloped compartments in the field. The full field 3-D model was constructed in such a way as to capture heterogeneities and the various compartments in the field. This was crucial to aid the simulation of fluid flow in the field for proper history matching, future production, prediction and design of well trajectories to adequately target undeveloped oil in the field.
Reservoir property models (Porosity, Permeability and Net-To-Gross) were constructed by biasing log interpreted properties to a defined environment of deposition model whose interpretation captured the heterogeneities expected in the studied reservoirs. At least, two scenarios were modelled for the studied reservoirs to capture the range of uncertainties.
This integrated approach led to the identification of bypassed oil in some areas of the selected reservoirs and an improved understanding of the studied reservoirs. Dynamic simulation and production forecast on the 4 reservoirs gave an undeveloped reserve of about 3.82 MMstb from two (2) identified oil restoration activities. These activities included side-tracking and re-perforation of existing wells. New wells have been drilled to test the results of our studies and the results confirmed our findings.
What Strategic Policies can Save Nigeria in the Energy Transition?
Authors: Ojukwu Kelechi 
Published: August 2021

Abstract
The world is fast changing and so is the energy mix. A global clarion call by scientists inspires an immediate action to circumvent the visible effects of climate change or face the damning consequences in the coming few years. Scientists and environmental lobbyist are campaigning against the consumption of fossil-based fuel and mounting more and more pressure on the international financial bodies including calling on government around the world to refrain from further financing of fossil fuel projects. This is surprisingly gathering momentum on regular basis, thereby posing existential threat to third-world oil producers, which are largely dependent on royalties and tax revenues from crude oil and other natural resources in order to sustain their economies. The future trends warn of a looming dooms day when these remaining reserves may no longer be able to attract the requisite funding necessary to develop them, let alone explore them.
Besides Niger Delta, most other petroleum basins in Nigeria are highly under-explored but presumed to have significant hydrocarbon resources, albeit mainly gas. For that reason, these basins and their resources do not yet count in the nation's wealth of booked resources. It is believed the country can also benefit from significant amounts of oil discoveries that are invisible to conventional technologies or intentionally bypassed in natural recovery methods. These could present less costly alternatives to uplift the nation's reserves booking and in so doing minimize uncertainty involved in deep water or frontier explorations. Nigeria should therefore aim to ramp up its capital investment to boost oil & gas production in the next couple of years so as to harness th abundant discovered resources whilst there is still time to do so.
To take advantage of Nigeria's vast portfolio of hydrocarbon resources, the nation must explore strategic policies aimed to enhancing exploration and production interests while simultaneously expanding other value chains and promoting the investment in alternative or renewable energy. It must expediently exploit the remaining reserves so as to make the most of what it has. Then the wind fall from that exploitation can be ploughed back into the economy to facilitate the implementation of large-scale alternative energy projects as it plans to eventually substitute the fossil fuel energy. This paper presents some thought-provoking but radical ideas of how this can be achieved in the near term.
A Comprehensive Review on CO2/N2 Mixture Injection for Methane Gas Recovery in Hydrate Reservoirs
Authors: Aregbe Azeez Gbenga , Fadeyi Ayoola Idris 
Published: August 2021

Abstract
Clathrate hydrates are non-stoichiometric compounds of water and gas molecules coexisting at relatively low temperatures and high pressures. The gas molecules are trapped in cage-like structures of the water molecules by hydrogen bonds. There are several hydrate deposits in permafrost and oceanic sediments with an enormous amount of energy. The energy content of methane in hydrate reservoirs is considered to be up to 50 times that of conventional petroleum resources, with about 2,500 to 20,000 trillion m3 of methane gas. More than 220 hydrate deposits in permafrost and oceanic sediments have been identified to date.
The exploration and production of these deposits to recover the trapped methane gas could overcome the world energy challenges and create a sustainable energy future. Furthermore, global warming is a major issue facing the world at large and it is caused by greenhouse gas emissions such as carbon dioxide. As a result, researchers and organizations have proposed various methods of reducing the emission of carbon dioxide gas. One of the proposed methods is the geological storage of carbon dioxide in depleted oil and gas reservoirs, oceanic sediments, deep saline aquifers, and depleted hydrate deposits. Studies have shown that there is the possibility of methane gas production and carbon dioxide storage in hydrate reservoirs using the injection of carbon dioxide and nitrogen gas mixture. However, the conventional hydrocarbon production methods cannot be used for the hydrate reservoirs due to the nature of these reservoirs. In addition, thermal stimulation and depressurization are not effective methods for methane gas production and carbon sequestration in hydrate-bearing sediments.
Therefore, the gas replacement method for methane production and carbon dioxide storage in clathrate hydrate is investigated in this paper. The research studies (experiments, modeling/simulation, and field tests) on CO2/N2 gas mixture injection for the optimization of methane gas recovery in hydrate reservoirs are reviewed. It was discovered that the injection of the gas mixture enhanced the recovery process by replacing methane gas in the small and large cages of the hydrate. Also, the presence of N2 molecules significantly increased fluid injectivity and methane recovery rate. In addition, a significant amount of free water was not released and the hydrate phase was stable during the replacement process. It is an effective method for permanent storage of carbon dioxide in the hydrate layer. However, further research studies on the effects of gas composition, particle size, and gas transport on the replacement process and swapping rate are required.
Produced Water Disposal in Deep Aquifers: Case History Review of Ughelli East-30 Pilot Injector
Authors: Peter Osode , Olusegun Oluwatoyin , Ologun Temitayo , Anyanwu Obinna 
Published: August 2021

Abstract
A water injector pilot well - Ughelli East-30, was drilled across high-permeability unconsolidated sandstone aquifers to dispose 30 Mbwpd of produced water in November 1998 and suspended in December 1998 due to lack of injectivity. Review of the failed pilot injection was performed as part of an extensive water management study for a cluster of onshore fields located in the western Niger Delta area.
The technical investigation focused on the target disposal aquifer petrophysical parameters, produced water composition analysis, well completion design and injection performance result. Potential impairment mechanisms and failure risk factors for injectors with similar cased-hole, perforated completion design in analogue reservoirs were also investigated.
The poor well injectivity performance was attributed to sub-optimal sand control completion design and the ‘water hammer’ effect which resulted in massive sand fill as evidenced by a sand bailing exercise during November 1999 riglessre-entry in the well. The 17-ft rat hole below the bottom aquifer sand perforations was also deemed to be inadequate for the sand fill which apparently bridged the perforations.
Optimal completion requirements to prevent water injection failure in unconsolidated sandstone formation has been brought to the fore in this paper which is expected to steer engineers focus to those factors with high impact on water injection system performance.
Taming the Monster: Arresting Excessive Sand Production Problem in ARAMU037
Authors: Ako Emily , Nnanna Erasmus , Somtochukwu Odumodu , Moradeke Akinmade 
Published: August 2021

Abstract
Chemical Sand Consolidation (SCON) has been used as a means of downhole sand control in Niger Delta since the early 70s. The countries where SCON has been used include Nigeria (Niger Delta), Gabon (Gamba) and UK (North Sea). SCON provides grain-to-grain cementation and locks formation fines in place through the process of adsorption of the sand grains and subsequent polymerization of the resin at elevated well temperatures. The polymerized resin serves to consolidate the surfaces of the sand grain while retaining permeability through the pore spaces.
In a typical Niger Delta asset, over 30% of the wells may be completed with SCON. A high percentage are still producing without failure since installation from1970s. Where the original SCON jobs have failed, re-consolidation has also been carried out successfully. Chemical Sand Consolidation development has evolved over the years from: Eposand 112A and B, Eposand 212A and B, Wellfix 2000, Wellfix 3000, Sandstop (resin based), Sandtrap 225, 350 & 500 (resin based) and lately Sandtrap 225,350, 500 (solvent based) and Sandtrap ABC (aqueous based).
There have been mixed results experienced with the deployment of either of the latest recipes of SCON. This was due to the fact that the conventional deployment work procedure was followed with the tendency for one-size-fits-all approach to the treatment.
This paper details the challenges faced with sand production in ARAMU037, the previous interventions and how an integrated approach to the design and delivery of the most recent intervention restored the way to normal production. The well has now produced for about 2 years with minimal interruption with the activity paying out in less than 6 months. The paper also recommends the best practice for remedial sand control especially for wells in mature assets.