bluuebunny/crossref_metadata_2025_split huggingface dataset:
Multiscale Pressure/Volume/Temperature Simulation of Decreasing Condensate/Gas Ratio at Greater than Dewpoint Pressure in Shale Gas-Condensate Reservoirs
Authors: Luo Sheng , Chen Fangxuan , Zhou Dengen , Nasrabadi Hadi 
Published: September 2021

Summary
In shale gas-condensate reservoirs, when the initial reservoir pressure is greater than the dewpoint pressure, the condensate/gas ratio (CGR) has been observed to decrease continuously as the pressure drops to less than the initial reservoir pressure. This abnormal behavior cannot be explained with conventional pressure/volume/temperature (PVT) models that ignore the presence of nanopores in shale rock. Herein, for the first time, we present a study that provides a physical explanation for the observed CGR trends by including the effect of nanopores on the fluid phase behavior and depletion of shale gas-condensate reservoirs. Our model uses multiscale PVT simulation by means of a pore-size-dependent equation of state (EOS). Two lean gas-condensate cases (shallow and deep reservoirs) are investigated. The simulation results show that hydrocarbons distribute heterogeneously with respect to pore size on the nanoscale. There are more intermediate to heavy hydrocarbons (C3–11+) but fewer light ends (C1–2) distributed in the nanopores than in the bulk region. At the end of depletion, because of confinement effects, large amounts of intermediate hydrocarbons are trapped in the nanopores, causing condensate recovery loss. Multiscale depletion simulations suggest that a decreasing CGR can occur at the beginning of production when the reservoir pressure is higher than the dewpoint pressure. Such behavior is caused by the nanopore depletion in the shale matrix, which is a process of selectively releasing light hydrocarbon components. We also present a novel approach to model the nonequilibrium fluid distribution between the fracture and nanopores using a simple local-equilibrium concept. Our results indicate that the nonequilibrium fluid distribution increases the CGR drop because of the compositional selectivity of the nanopore in favor of intermediate and heavy hydrocarbons.
NOTE: This paper is published as part of the 2021 SPE Reservoir Simulation Conference Special Issue.
An Industry First - A Successful Managed Pressure Horizontal Open Hole Gravel Pack Project: Its Preparation, Integration, Modeling, Procedures, and Execution Results
Authors: Lin Chih-Cheng , Vives Javier , Kaura Jiten , Tallin Andrew G , Campbell Patrick , Hahn Christine , Jimenez Eduardo , Kadam Nilesh , Byargeon Jenny , Stewart Buster , Karber Derrek , Pittman Adam , Noort Roger Van , Luces Sasha , Prince John , Benson Dan , Weirich John B. , Joseph Alicia , Mukashev Nurtas , Gillette Robert , Aye Yeneapre , Smith Dave 
Published: September 2021

Abstract
This paper presents how a Controlled Mud Level (CML) Managed Pressure Drilling (MPD) system was used to place Horizontal Open Hole Gravel Packs (HzOHGP) in low Pore Pressure Frac Gradient (PPFG) margin reservoirs. This industry-first accomplishment took extensive preparation and precise on-site coordination between CML and gravel pack operations. In the target reservoirs, the margin between the pore and fracture pressures is too small to place gravel packs using conventional methods. CML was identified as an opportunity to resolve this problem. A primary design phase goal was to develop a deep understanding of the flow paths and fluid properties at every stage of the gravel pack operation. This information is critical to evaluating the frictional pressure drops effecting the pressure in the open hole. The team developed procedures that incorporated step rate tests and real-time downhole measurements to calibrate the friction models, which were then used to precisely control the CML during the pumping jobs. CML was able to limit the downhole treating pressures to stay within the low PPFG limits. The post-job analyses showed that total screen coverage was achieved for all the jobs in the campaign, demonstrating the project team's high level of coordination, cooperation, and cross-discipline understanding. While the industry had adopted CML and HzOHGP systems separately prior to this project, this operation marks the first time they have been combined.
Expanding Horizon - A Feasibility Study on Implementing PMCD Operation Using Coiled Tubing Drilling Technology to Develop Marginal Reserves in Karstic Carbonate Reservoir, Offshore Malaysia
Authors: Zakaria Ahmad Zahid Murshidi , Khalid Muhammad Idham , Effendi Shahrul Nizam Mohd , Arathoon Mark , Abidin Mohamad Zakwan Zainal , Jalil Mohamad Afzal Abdul 
Published: September 2021

Abstract
With the current uncertain situation regarding the stability of oil prices in the world, operators have been pushed to develop their available resources in a cost-effective way. Lately, there has been increased interest in the application of Coiled Tubing Drilling, especially for accessing bypassed hydrocarbon in mature or late-stage fields. This paper describes the feasibility study done to examine the possibility of using Coiled Tubing Drilling package/equipment to drill and complete a sidetrack well in a karstic carbonate reservoir with total losses issue by applying the principles of Pressurized Mud Cap Drilling (PMCD). This will be the first time that such method is being utilized for developing karstic carbonate reservoirs in Offshore Malaysia. The paper will go through the background of the project (generic field information, reservoir properties, well design and architecture), the critical design elements for the system (technical requirements, safety standards, operational and logistical factors) and the contingency scenarios considered. Based on the aforementioned items, a fit-for-purpose Coiled Tubing Drilling equipment arrangement together with suitable PMCD method and light annular mud (LAM) selection were proposed to cater for the specific challenges of the well. It was concluded that the application of PMCD using Coiled Tubing Drilling Package is feasible with some modification to the equipment, line up and operational procedures.
First Managed Pressure Cementing with 7" Liner Overcoming a Challenging ERD Well Offshore Madura
Authors: Samudera Galih , Ali Hafidz , Bin Musa Mohammad Zarir , Fauzi Helmi , Rubianto Irwan , Kumar Avinash Kishore , Hen Lau Chee , Azrai Remy 
Published: September 2021

Abstract
ZX was a development well located in offshore Madura, Indonesia. ZX was classified as an Extended Reach Drilling (ERD) well with 2.40 ERD ratio. ZX well was in KX field which known to have several drilling hazards. The formation had multiple lost circulation zones below the 9 5/8" casing shoe that was prone to total and partial losses due to combination depleted formation in the upper side and the nature of karst or fractured carbonate formation in middle and lower part of the interval. In addition, the bottom part of the hole section had the problematic wellbore instability. These hazards led to the necessity to closely monitor and control the pressure profile throughout the operation to find balance between loss circulation and wellbore stability to ensure an efficient and safe operation.
An automated managed pressure drilling (MPD) system was used to precisely control bottom hole pressure. MPD system was used to drill 8-1/2" section of ZX well smoothly to target depth and geological objective was achieved without NPT. MPD cementing was performed successfully for 7" liner operation. This was the first managed pressure cementing (MPC) operation in offshore Madura and the application mitigated the loss circulation and avoided the unnecessary remedial cementing job.
The paper shared the success MPD story of extremely narrow window ERD well in offshore Madura, Indonesia. It aimed to describe the application of MPD for this specific ERD case from planning phase to execution phase as well as the lesson learned.
Reclaiming the Operating Window: A Managed Pressure Cementing Workflow to Achieve Zonal Isolation Success in a Mature Field
Authors: Smith Jeffrey , Rossi Lucas , Mehler Christopher , Eberhardt Jon Todd , Scarborough Christopher , Leemhuis Jacob , Essam Wael 
Published: September 2021

Abstract
Successfully cementing production casing strings is one of the main challenges of well construction in mature fields. The implementation of cementing best practices can be difficult in the narrow pore pressure-fracture pressure (PPFG) window associated with reservoir depletion and complex well architecture. The increased risk of losses can lead operating teams to compromise on these best practices, often jeopardizing the zonal isolation objectives. This can result in significant additional time, cost, and production deferral/loss.
Managed pressure cementing (MPC) is a viable technique to address these challenges. Using the managed pressure drilling (MPD) system's capability to precisely control bottomhole pressure, coupled with the use of mud weights that are lower than conventionally needed can expand the PPFG window; enabling operating teams to achieve a higher success rate in meeting the zonal isolation objectives.
This paper will offer an optimized design methodology and critical considerations and parameters for MPC operations. It will also briefly describe the primary applications of MPC and specific, unique design considerations associated with each, namely, (1) mud weight less than pore pressure (PP), (2) losses prevention, and (3) wellbore stability control. Lastly, it will provide a case history illustrating how MPC was used in one of the operator's mature fields, by giving an overview of the job engineering design process, the operational planning (inclusive of contingencies), and the key highlights and learnings observed during execution.
Evolution Characteristics and Relationship of Meteorological and Hydrological Droughts from 1961 to 2018 in Hanjiang River Basin, China
Authors: Wang Lin , Zhang Jianyun , Elmahdi Amgad , Shu Zhangkang , Bao Zhenxin , Peng Tao , Lin Qingxia , Wang Guoqing 
Published: September 2021

Abstract
In the context of global warming and increasing human activities, the acceleration of the water cycle will increase the risk of basin drought. In this study, to analyze the spatial and temporal evolution characteristics of hydrological and meteorological droughts over the Hanjiang River Basin (HRB); the Standardized Precipitation Index (SPI) and Standardized Runoff Index (SRI) were selected and applied for the period 1961–2018. In addition, the cross-wavelet method was used to discuss the relationship between hydrological drought and meteorological droughts. The results and analysis indicated that: (1) the meteorological drought in the HRB showed a complex cyclical change trend of flood-drought-flood from 1961 to 2018. The basin drought began to intensify from 1990s and eased in 2010s. The characteristics of drought evolution in various regions are different based on scale. (2) During the past 58 years, the hydrological drought in the HRB has shown a significant trend of intensification, particularly in autumn season. Also, the hydrological droughts had occurred frequently since the 1990s, and there were also regional differences in the evolution characteristics of drought in various regions. (3) Reservoir operation reduces the frequency of extreme hydrological drought events. The effect of reducing the duration and intensity of hydrological drought events by releasing water from the reservoir is most obvious at Huangjiagang Station, which is the nearest to Danjiangkou Reservoir. (4) The hydrological drought and meteorological drought in the HRB have the strongest correlation on the yearly scale. After 1990, severe human activities and climate change are not only reduced the correlation between hydrological drought and meteorological drought in the middle and lower reaches of the basin, but also reduced the lag time between them. Among them, the hydrological drought in the upper reaches of the basin lags behind the meteorological drought by 1 month, and the hydrological drought in the middle and lower reaches of the basin has changed from 2 months before 1990 to 1 month lagging after 1990.
QTL Mapping for 1000-grain Weight and Its Main Components in Wheat
Authors: zhang hong , Bao Yin-guang , Li Xing-feng , Feng De-shun , Wang Hong-gang 
Published: September 2021

Abstract
In order to identify QTLs for 1000-grain weight and its main component traits in wheat, a high-density genetic link map was constructed using a F8:9 recombined inbred line (RIL) population as material and exploiting the single nucleotide polymorphism (SNP) as well as PCR-based molecular markers, and to go a step further, QTL mapping for 1000-grain weight, grain length, and grain width in wheat was conducted. The linkage map was composed of 1257 loci formed by the 3916 markers, including 143 SSR markers and 3773 SNP markers, which were distributed on 22 chromosomes (2A chromosome formed a break point) with the total length of 2291.6 cM and the average genetic distance between loci of 1.82 cM. A total of 41 qualitative trait loci (QTLs) on 19 chromosomes were detected, with contributions to phenotypic variance ranged from 3.59–58.49% for each QTL. Among these QTLs, two were detected in four environments, six in three environments, and 14 in two environments. Fifteen important loci with multi-effect were mapped on 9 chromosomes 1B, 2B, 3A, 4B, 5A, 5B, 6A, 7A, and 7B, involving 37 QTLs that accounted for 90.2% of total numbers of QTLs detected. Of these 15 loci, including one on chromosome 7A flanked by the markers Tdurum_contig77759_5 and BS00062425_51, which consisted of QTLs controlling TGW, GL, and GW and explained 4.2 to 58.49% of the phenotypic variation in these traits. Thus, the chromosome intervals of the 15 loci were important areas controlling the expression of 1000-grain weight and its main component traits in wheat.
Estimating the Methane Emissions and Energy Potential from Trichy and Thanjavur Dumpsite by LandGEM Model
Authors: Busetty Subramanyam 
Published: September 2021

Abstract
One major factor, contributing to the emission of greenhouse gas in the environment is generation of hazardous gases in municipal landfills. Due to these potential negative impacts, it is obligatory to estimate the amount and type of landfill gasses to design and build a gas collecting system. Landfill gas emissions are governed by the type of waste, its biodegradability, its methane emission potential, the degree of separation and other miscellaneous factors. There are various US EPA recommendation model. The Landfill Gas Emissions Model (LandGEM) is one the conventional model and also provides better estimation compared to other method. It is used to the amount of gases produced in the landfills of Trichy (Ariyamangalam) landfill and Thanjavur (Srinivasapuram) landfills have been predicted. According to the results, the largest amount of landfill gas emissions would be in 1993 for Trichy (Ariyamangalam) landfill and in 2027 for Thanjavur (Srinivasapuram) landfill. The total amount of produced gas, methane and carbon dioxide would be 16.2E + 10, 8.2E + 10 and 16.2 + 10 cubic meters per year in 1993 for trichy and 13E + 6, 5E + 6 and 13E + 6 cubic meters per year in 2027 for Thanjavur.
Pharmacokinetics and Bioequivalence of Sitagliptin Phosphate/Metformin Hydrochloride Tablets in Healthy Chinese Subjects: A Randomized, Open, Crossover Study
Authors: SHI Ping , LIU Xin , LI Ting , SUN Fei-fei , LIU Yan-ping , LIU Shu-qin , GAO Xiao-meng , MA Ya-ping , FU Yao , CAO Yu 
Published: September 2021

Abstract
Objective To evaluate the pharmacokinetics and bioequivalence between Sitagliptin Phosphate/metformin Hydrochloride Tablets (test formulation) at a single dose of 50mg/850mg and Sitagliptin Phosphate/metformin Hydrochloride Tablets (reference formulation, JANUMET®) at a single dose of 50mg/850mg in healthy Chinese subjects.Methods The study was designed as a randomized, open-lable, two-period double-crossover trial. A total of 24 volunteers under fasting condition and 24 subjects under fed condition were given a single oral dose of 50mg/850mg Sitagliptin Phosphate/metformin Hydrochloride Tablets of test and reference, respectively. Liquid chromatography Tandem mass spectrometry (LC-MS/MS) method was used to determine the concentrations of sitagliptin and metformin in the plasma of subjects. The pharmacokinetic parameters were calculated by WinNonlin 7.0 program and the bioequivalence was evaluated by SAS 9. 4program. Results The 90% confidential interval (CI) of geometric mean ratio under fasting condition for Cmax, AUC0-t and AUC0-∞ of sitagliptin between the test group and the reference group were 101.70%-120.62%, 99.81%-105.61%, 100.27%-106.12% and metformin were 90.39%-111.48%, 94.76%-109.12%, 95.76%-110.38%. The 90% CI of geometric mean ratio under fed condition for Cmax, AUC0-t and AUC0-∞ between the test group and the reference group were 102.12%-117.31%, 100.80%-107.81%, 100.82%-107.78% and metformin were 95.53%-105.22%, 92.76%-103.07%, 93.40%-104.14%. Both were generally well tolerated.Conclusion The two formulations of Sitagliptin Phosphate/metformin Hydrochloride Tablets were bioequivalent under fasting and fed condition in healthy Chinese subjects.Trial registration Clinical Trial Registry (trial ID: NCT04877106).
Synthesis And Study The Concentration Effect On The Photocatalytic Activity of Titania Nanoparticles As Anti-Bactria Using Reactive Magnetron Sputtering Technique
Authors: Al-Maliki Firas J. , Al-Rubaiy Maryam A. 
Published: September 2021

Abstract
In this work, the dc reactive magnetron sputtering technique was used to prepare and deposit nanostructured titanium dioxide (TiO2) thin films on glass substrates. Titanium dioxide thin films of mixed phase (anatase + rutile) and single phase (anatase) were prepared using different gas mixing ratios, and for both of the two phases, they were diagnosed via x-ray diffraction (XRD). It was found that the contents of rutile in mixed phase dependent on the deposition time increased from the ratio of 40% to 46% and 50% as the deposition time increased from 3 hours to 3.30 and 4 hours. The photocatalytic activity of the mixed and single phase TiO2 was measured by kill the bacteria Escherichia coli (E.Coli) under exposure to UV-radiation. It was proven that the photocatalytic activity in the mixed phase (TiO2) gave better results weight fraction is 40% as an antibacterial activity. Based on the obtained results anti-bacterial activity of dioxide titanium nanoparticles was dependent on the concentration and phase of TiO2 and weight fraction of mixed-phase.
An Efficient Nonlinear Optical, Magnetic Transition Metal Ion Nickel Doped L- Threonine Cadmium Acetate Monohydrate
Authors: RN ANILA , Bright KC 
Published: September 2021

Abstract
The semi organic nonlinear optical single crystal of L- Threonine Cadmium acetate Monohydrate (LTCAM) doped Ni 2+ion is prepared by the technique slow evaporation solution growth. The prepared crystal was analysed by XRD, EDAX, UV-Vis- NIR, IR, TG/DTA, Photo Luminescence (PL), VSM and SHG measurements. The SXRD shows the crystal come under the monoclinic crystal system with P21 noncentrosymmetric space group. In the visible and near infrared region the crystal shows good optical response and it is a thermally stable compound. The band gap of the grown crystal was 5.02ev. The functional groups are confirmed by FTIR analysis. The luminescent behaviour of the doped crystal shows its ability as UV filters. The dopant turns its magnetic property in to semi paramagnetic nature.
Effect of Nitrogen Doping On The Structural Surface And Optical Properties Of ZnO Thin Film Prepared By Spraypyrolysis
Authors: ES Rajalekshmi , Ferby V. Anslin , Shabu R. , Raj A. Moses Ezhil 
Published: September 2021

Abstract
Pure and Nitrogen doped ZnO thin films were fabricated using spray pyrolysis method. The influence of doping on the structural, optical and morphological properties of prepared films were studied. The prepared samples were characterized through XRD (X-Ray Diffraction), FTIR (Fourier Transform Infrared Spectroscopy), FT-RAMAN (Fourier Transform Raman), optical transmittances of prepared films were studied as a function of wavelength using UV-VIS-NIR spectrophotometer and SEM (Scanning Electron Microscope). Absorption coefficient and Extinction coefficient values were calculated. Thickness of the films were found increasing with increasing doping concentrations. Structural studies confirmed that the prepared films were highly crystalline and predominantly orientation along (0 0 2) direction. On varying the doping concentration of N, a shift in the (0 0 2) peak was observed. FTIR and Raman spectral investigations revealed bands at specified wavenumber regions corresponding to stretching and bending vibrations of Zn and O. High resolution SEM images proved the presence of regular distribution of grains and the surface was found continuous, free from crack and holes. EDAX spectrum shows the attained films contain of Zinc, Oxygen and Nitrogen elements. Present investigations confirmed the fusion of nitrogen into ZnO lattice and modified the structural, optical and morphological properties of ZnO films.
Structural and Electrical Studies of Bi2Se3 Nanomaterials by Solvothermal Method for Thermo-electric Applications
Authors: V Asvini , S Subbulekshmi , G Saravanan , K Ravichandran 
Published: September 2021

Abstract
The Bi2Se3 nanoparticles were synthesized by the solvothermal method. The structural and morphological characterization has been done using XRD, HRSEM and Raman while electrical studies at room temperature were analyzed using impedance spectroscopy and cyclic voltmetry. The phase formation was confirmed through XRD measurement and average grain size was found to be 25 nm for as-prepared sample and 37 nm for 650 ºC for 12 hours annealed sample. Raman spectrum appears in the higher frequency range, this is due to stronger bonding forces, i.e the peak at 524 cm− 1 or may arise due to the overtones of A11g and E2g modes. The redox behavior was due to Bi3+ converted into Bi2+ and Bi metallic state. This redox peak was confined the formation of Bi2Se3 nanoparticles. The high temperature electrical conductivity studies were performed as-prepared and annealed sample using impedance spectroscopy.