bluuebunny/crossref_metadata_2025 huggingface dataset:
High performance Sr4Al14O25:Mn4+ phosphor: structure calculation and optical properties
Authors: Wang Xingsen , Jiang Quan , Wang Zixiang , Song Biqing , Hou Hailan , Xu Liang , Xia LiBin
Published: April 2022

The Sr4Al14O25:Mn4+ red phosphor can be excited by blue light to achieve warm-WLEDs. Theoretical calculation and experiments have both demonstrated that Mg2+ doping can improve the PL intensity and thermal quenching properties of the phosphor.
An analysis of the most distant cataloged open clusters
Authors: Perren G. I. , Pera M. S. , Navone H. D. , Vázquez R. A.
Published: April 2022

Context. Several studies have been presented in the last few years applying some kind of automatic processing of data to estimate the fundamental parameters of open clusters. These parameters are then employed in larger scale analyses, for example the structure of the Galaxy’s spiral arms. The distance is one of the most straightforward parameters to estimate, yet enormous differences can still be found among published data. This is particularly true for open clusters located more than a few kiloparsecs away.

Aims. We cross-matched several published catalogs and selected the 25 most distant open clusters (> 9000 pc). We then performed a detailed analysis of their fundamental parameters, with emphasis on their distances, to determine the agreement between the catalogs and our estimates.

Methods. Photometric and astrometric data from the Gaia EDR3 survey was employed. The data were processed with our own membership analysis code, pyUPMASK, and our package for the automatic estimation of fundamental cluster parameters, ASteCA.

Results. We find differences in the estimated distances of up to several kiloparsecs between our results and those cataloged, even for the catalogs that show the best matches with ASteCA values. Large differences are also found for the age estimates. As a by-product of the analysis we find that vd Bergh-Hagen 176 could be the open cluster with the largest heliocentric distance cataloged to date.

Conclusions. Caution is thus strongly recommended when using cataloged parameters of open clusters to infer large-scale properties of the Galaxy, particularly for those located more than a few kiloparsecs away.
The use of pectin extracts from chaenomeles fruits in bakery
Authors: Sokol Natalia , Sanzharovskaya Nadezhda , Khrapko Olga
Published: April 2022

Currently, an urgent task is the creation of food products with directed biological activity through the use of natural ingredients. The mass consumption of bread gives reason to consider it as a product with exceptional potential and significance for improving the quality of nutrition and protecting the organism from the effects of harmful environmental factors. The aim of the research is to study the chaenomeles fruits, to determine the rational parameters for obtaining pectin extracts and to evaluate their effect on the baking properties of flour, the course of the technological process and the quality of finished bakery products. The objects of the research were chaenomeles fruits; pectin extracts; wheat flour; prototype bread samples. It has been studied the kinetics of pectin substances extraction and has been proposed the process rational parameters, which make it possible to obtain extracts with high functional and technological properties. It is shown that the addition of pectin extract from chaenomeles fruits at a dosage of up to 15 % improves the quality characteristics of bread. The proposed recipe allows obtaining high-quality enriched bakery products.
Study of the influence of the process of freezing milk on the safety of its properties of cheese suitability
Authors: Mordvinova Valentina , Sviridenko Galina , Ostroukhova Irina , Shukhalova Olga , Mamykin Denis
Published: April 2022

The article presents the results of studies of the effect of freezing on the change in the physicochemical, microbiological and technological properties of goat milk and the preservation of its qualities of cheese suitability. A statistically significant dependence of the composition of milk on the duration of storage in a frozen state was revealed. There was no significant effect of freezing and defrosting modes on the quality indicators of milk. It has been established that changes in the technological properties of frozen goat milk after defrosting, such as the duration of coagulation and the ability to syneresis, are insignificant in comparison with defrosted cow's milk.
The need for enrichment of meat products with micronutrients
Authors: Vasyukova Anna , Lyubimova Kristina
Published: April 2022

The article discusses the chemical composition of meat according to the main qualitative characteristics to identify the least nutritious product for its subsequent enrichment with various micronutrients. The introduction of dishes and products with an adjusted composition of vitamins, macro- and microelements into the existing diet of an average person is a serious intervention in the traditionally established structure of human nutrition. The need for such an intervention is determined by objective environmental factors associated with changes in the composition and nutritional value of the products that are used in daily nutrition, as well as changes in our lifestyle, with a decrease in physical activity and energy consumption. For these reasons, this intervention should only be carried out in accordance with scientifically sound and proven principles. The choice of micronutrients is quite diverse and, depending on the task of enriching meat products, it is possible to satisfy various physiological needs of the population.
Biotransformation of chemical components of rare cultures under the action of the enzyme preparation Trenolin Opti DF
Authors: Droficheva Natalia , Smelik Tatyana
Published: April 2022

The technological process of processing rare crops requires the use of enzyme preparations to soften the pulp and destroy the structure of polysaccharides, as well as increase the content of sugars, namely glucose and sucrose. Biochemical indicators of the quality of the fruits of krebs and chenomelys in the varietal section have been determined. The effect of the enzyme preparation - Trenolin Opti DF on the extraction of vitamins and polyphenolic substances has been investigated. The effectiveness of the enzyme preparation was judged by the biotransformation of the chemical components of the crushed mass from the fruits of rare crops. The effect of the enzyme preparation on the output and quality of fruit juice has been established.
Ensuring the preservation of the quality of wine during storage
Authors: Chemisova Larisa , Ageeva Natalia , Mitrofanova Ekaterina , Sheludko Olga
Published: April 2022

The article presents the necessity for a detailed approach to the choice of packaging for wine, as well as assessing their quality level. It has been established that the transformation of the component composition of wine proceeds with different intensity depending on the type of packaging and leads to different consequences, mainly due to the occurrence of redox reactions, as well as the degree of gas exchange during storage. Complex packaging "package in a box" can become a source of premature oxidation of wines and the appearance of foreign synthetic inclusions in them.
Changes in the antioxidant activity of red dry wines depending on the production method
Authors: Antonenko Olga , Guguchkina Tatiana , Chemisova Larisa , Antonenko Mikhail , Yakimenko Elena
Published: April 2022

It is found that a production method affects the antioxidant activity of researched red dry wines made grapes produced in Kuban area. According to results of multivariate analysis of variance, grape variety (59% of influence), production method (27%) and usage of antioxidants during must extraction (7%) influenced on antioxidant activity values.
Studies on the identification of frostbitten and frozen meat after defrosting by the spectrophotometric method for determining DNA in muscle tissue extracts
Authors: Donetskikh Alexander , Dibirasulaev Magomed , Belozerov George , Dibirasulaev Dibirasulav
Published: April 2022

Changes in the state of meat during freezing are determined by the phase transition of water into ice and an increase in the concentration of substances dissolved in the liquid phase. The process of crystal formation leads to a change in the physical characteristics of the meat and may be accompanied by changes in its structural properties. The effect of the proportion of frozen water on the permeability of the membranes of muscle fibers of frostbitten and frozen meat has been established. The ratio of optical densities at wavelengths of 270 nm and 290 nm (R) can be used to judge the thermal state of the meat. It is shown that the value of R after defrosting frozen meat is 2 times higher than for frostbitten meat.
Staged Common and External Carotid Artery Stenting Followed by Superficial Temporal Artery to Middle Cerebral Artery Bypass
Authors: Mulcahy Michael , Presti Anna Lo , Veken Jorn Paul Van Der , Steinfort Brendan , Assaad Nazih
Published: April 2022

Superficial temporal artery (STA) to middle cerebral artery (MCA) bypass surgery for internal carotid artery (ICA) occlusive disease necessarily requires sufficient external carotid artery (ECA) blood flow. Surgical bypass is therefore precluded if there is common carotid artery (CCA) occlusion. Here we present two such cases: one patient had a CCA occlusion and the other had an ICA occlusion and ECA stenosis. Both had failed medical management, and were therefore treated with angioplasty and stenting of the ECA, followed by STA-MCA bypass. We describe the clinical and radiologic outcomes of these cases, and remark on the potential pitfalls associated with this novel approach.
Device activism and material participation in healthcare: retracing forms of engagement in the #WeAreNotWaiting movement for open-source closed-loop systems in type 1 diabetes self-care
Authors: Jansky Bianca , Langstrup Henriette
Published: April 2022

The #WeAreNotWaiting movement is a global digital health phenomenon in which people with diabetes, mainly type 1 diabetes (T1D), engage in the development and usage of open-source closed-loop technology for the improvement of their “chronic living” (Wahlberg et al. 2021). The characteristics of a digitally enabled and technologically engaged global activist patient collective feed into existing narratives of user-led and open-source innovation. They also call for more exploration of what it actually means to be locally involved in this kind of technologically mediated and global form of patient engagement. Building on empirical research conducted in the German healthcare context, we explore the different forms of material participation encountered among a group of people with T1D (who describe themselves as loopers), who are engaged in the development and usage of this open-source technology. Introducing the concept of device activism, we retrace three different device-centered narratives that show how a globally shared concern and political participation through technology use varies with local practices. Hereby we stress that the engagement in the #WeAreNotWaiting movement is both shaped by and is shaping the matters of concerns: devices in, on, and with bodies.
Designing a better electrode for redox flow batteries
Authors: Kim Meeri
Published: April 2022

New simulation framework models electrolyte fluid flow in order to optimize electrode geometry, finds less is more
Local measurement of bulk thermal diffusivity using photothermal radiometry
Authors: Hua Zilong , Schley Robert , Hurley David
Published: April 2022

An experimental methodology using photothermal radiometry is developed for the accurate measurement of bulk thermal diffusivity of nuclear fuels and materials irradiated to high doses. Under these conditions, nuclear fuels, such as uranium oxide, and moderator materials, such as graphite, become friable, which requires characterization techniques that can accommodate irregularly shaped fragments. Photothermal radiometry, a good candidate for this application, involves locally heating a sample by using a laser and measuring the temperature field by monitoring blackbody radiation. The interaction volume for this study, less than a millimeter, is carefully chosen to sample a statistically significant number of large-scale structural features, such as pores and gas filled bubbles, and is small enough that the sample fragments can be treated as a thermal half-space. The thermal diffusivity standards considered in this study cover a range of thermal diffusivities representative of both fresh and spent nuclear fuels. We also consider a sample having a porous microstructure representative of large-scale structures found in materials irradiated to high doses. Our measurement methodology circumvents complex thermal wave models that address optical diffraction, nonlinear transfer function associated with blackbody radiation, and finite sample size effects. Consequently, the large measurement uncertainty associated with modeling these effects can be avoided. While the emphasis here is on nuclear fuels and materials, this measurement approach is well suited to measure thermal transport in a variety of technologically important materials associated with advanced synthesis techniques. Examples range from small, exotic single crystals grown using hydrothermal growth techniques to additively manufactured components having complex geometries.
The mechanism for ligand activation of the GPCR–G protein complex
Authors: Mafi Amirhossein , Kim Soo-Kyung , Goddard William A.
Published: April 2022

Significance

We report the detailed atomistic mechanism for how molecules such as morphine, dopamine, or epinephrine binding outside of a cell to a G protein–coupled receptor (GPCR) in the cell membrane cause a G protein (GP) bound at the inside of the cell to break apart and signal the cell to influence appetite, anxiety, memory, cognition, learning, and sleep. Most surprising is that the GP binds first to the GPCR to form a precoupled complex that remains at rest until the drug binds to induce the signaling. Most important, it is the precoupled GPCR-GP structure that provides the basis for the design of therapeutics to maximize activity and selectivity.
Planetary chaos and inverted climate phasing in the Late Triassic of Greenland
Authors: Mau Malte , Kent Dennis V. , Clemmensen Lars B.
Published: April 2022

Significance

Our study of climate response to orbital variations in a Late Triassic midlatitude temperate setting in Jameson Land, East Greenland, provides robust evidence of astronomically forced grand cycles ascribed to gravitational interactions between Earth and Mars and is an Early Mesozoic record where both Mars–Earth modulation components are present and constrained with adequate chronostratigraphic controls. These findings suggest chaotic behavior of the inner Solar System and have implications as reference points in calculations of the past motions of the planets in the Solar System. Furthermore, our findings demonstrate a climate antiphasing between low and midlatitudes, which has implications for precise correlation of geological records and for validating models of Earth’s climate dynamics.
Gate-tunable contact-induced Fermi-level shift in semimetal
Authors: Li Xuanzhang , Wei Yang , Lu Gaotian , Mei Zhen , Zhang Guangqi , Liang Liang , Li Qunqing , Fan Shoushan , Zhang Yuegang
Published: April 2022

Significance

Resistivity comparison methodology was developed to measure and analyze the contact-induced Fermi-level shift (CIFS) as well as the interfacial charge transfer in low-dimensional semimetal–semiconductor (Sm-S) systems. The Fermi-level catch-up model was further built to depict the gate-tunable CIFS in such Sm-S systems. The Schottky barrier height for the Sm-S junction can be modified by introducing the CIFS term. The progress in this work will have an important role in promoting the research of Sm-S junctions, which are essential building blocks for future low-dimensional nanodevices.
Hybrid Hadamard and controlled-Hadamard based quantum random number generators in IBM QX
Authors: Salehi Ramin , Razaghi Mohammad , Fotouhi Bashir
Published: April 2022

Designing novel circuits and models for generating truly random numbers is of great importance. Recent attention has been focused on the idea of using real quantum computers to generate random numbers. In order to generate purely random bits and numbers, one method relies on the natural superposition of quantum gates. Here, we design a Quantum Random Number Generator (QRNG) exploiting combinations of Hadamard and controlled-Hadamard gates in IBM Quantum Experience (QX). In order to verify that the generated bit sequences were truly random, the proposed circuit’s outputs were subjected to the National Institute of Standards and Technology (NIST) test suite. In comparison to previous works, we found that not only had the total number of passed tests increased, but the P-values had also improved in many cases. For example, in the simulation style of the IBM QX, the number of passed tests is 14 out of 15 standard NIST tests. For the experimental mood of the IBM 16Q Melbourne, the number of passed tests is six without using any extractions. Furthermore, one more test is passed by adding Barrier operations to the circuits, and the P-values have increased. As a result, we found that the proposed method had more passed tests than previous works. The average of P-values for the six passed tests in former research for the mood of using a combination of extractors is about

0.43
.

However, the best result we can get with our circuits is around 0.60 (the average of P-values for 14 passed tests), which is an improvement of 0.17 compared to former works . Because of this, our circuits are getting ever closer to being a true QRNG.
Kinetic theory of longitudinal stability analysis of a non-laminar electron beam in self-consistent plasma wake field excitation
Authors: Akhter Tahmina , Fedele Renato , De Nicola Sergio , Jovanović Dusan , Fiore Gaetano
Published: April 2022

We carry out a stability analysis of a relativistic nonlaminar electron beam which is experiencing the self-consistent plasma wake field excitation. This is done in overdense regime (i.e. plasma density much greater than beam density) in a cold plasma. We adopt the self-consistent kinetic model for the plasma wake field excitation, that is based on the pair of Vlasov-Poisson-type equations. The latter governs the phase-space spatiotemporal evolution of the beam and its linearized form leads to a Landau-type approach to the beam stability analysis. Thereby, the analysis, performed for the case of a Gaussian electron beam distribution, shows the existence of the unstable modes for both cold and warm beams, respectively.
Achieving highly-efficient H2S gas sensor by flower-like SnO2–SnO/porous GaN heterojunction
Authors: Liu Zeng , Du Ling , Zhang Shao-Hui , Bian Ang , Fang Jun-Peng , Xing Chen-Yang , Li Shan , Tang Jin-Cheng , Guo Yu-Feng , Tang Wei-Hua
Published: April 2022

A flower-like SnO2–SnO/porous GaN (FSS/PGaN) heterojunction was fabricated for the first time via a facile spraying process, and the whole process also involved hydrothermal preparation of FSS and electrochemical wet etching of GaN, and SnO2–SnO composites with p–n junctions were loaded onto PGaN surface directly applied to H2S sensor. Meanwhile, the excellent transport capability of heterojunction between FSS and PGaN facilitates electron transfer, that is, a response time as short as 65 s and a release time up to 27 s can be achieved merely at 150 °C under 50 ppm H2S concentration, which has laid a reasonable theoretical and experimental foundation for the subsequent PGaN-based heterojunction gas sensor. The lowering working temperature and high sensitivity (23.5 at 200 ppm H2S) are attributed to the structure of PGaN itself and the heterojunction between SnO2–SnO and PGaN. In addition, the as-obtained sensor showed ultra-high test stability. The simple design strategy of FSS/PGaN-based H2S sensor highlights its potential in various applications.
A New Consistency Test for ΛCDM Cosmology Using Galaxy Surveys
Authors: Zheng Jinglan , Zhao Gong-Bo , Wang Yuting , Mu Xiaoyong , Zhao Ruiyang , Zhang Weibing , Yuan Shuo , Bacon David , Koyama Kazuya
Published: April 2022

We propose a new consistency test for the ΛCDM cosmology using baryonic acoustic oscillations (BAO) and redshift space distortion (RSD) measurements from galaxy redshift surveys. Specifically, we determine the peak position of f
σ
8(z) in redshift z offered by an RSD measurement, and compare it to the one predicted by the BAO observables assuming a flat ΛCDM cosmology. We demonstrate this new test using the simulated data for the DESI galaxy survey, and argue that this test complements those using the background observables alone, and is less subject to systematics in the RSD analysis, compared to traditional methods using values of f
σ
8(z) directly.
The Co-alignment of Winged Hα Data Observed by the New Vacuum Solar Telescope*
Authors: Cai Yun-Fang , Yang Xu , Xiang Yong-Yuang , Yan Xiao-Li , Jin Zhen-Yu , Liu Hui , Ji Kai-Fan
Published: April 2022

The New Vacuum Solar Telescope (NVST) has been releasing its novel winged Hα data (WHD) since 2021 April, namely the Hα imaging spectroscopic data. Compared with the prior released version, the new data are further co-aligned among the off-band images and packaged into a standard solar physics community format. In this study, we illustrate the alignment algorithm used by the novel WHD, which is mainly based on the optical flow method to obtain the translation offset between the winged images. To quantitatively evaluate the alignment results of two images with different similarities, we calculate the alignment accuracies between the images of different off-band and line center, respectively. The result shows that our alignment algorithm could reach up to the accuracy of about 0.″1 when the off-band of winged image is lower than 0.6 Å. In addition, we introduce the final product of the WHD in detail, which can provide convenience for the solar physicists to use high-resolution Hα imaging spectroscopic data of NVST.
Angle-tuned coils: attractive building blocks for TMS with improved depth-spread performance
Authors: Bagherzadeh Hedyeh , Meng Qinglei , Deng Zhi-De , Lu Hanbing , Hong Elliott , Yang Yihong , Choa Fow-Sen
Published: April 2022

Objective. A novel angle-tuned ring coil is proposed for improving the depth-spread performance of transcranial magnetic stimulation (TMS) coils and serve as the building blocks for high-performance composite coils and multisite TMS systems. Approach. Improving depth-spread performance by reducing field divergence through creating a more elliptical emitted field distribution from the coil. To accomplish that, instead of enriching the Fourier components along the planarized (x-y) directions, which requires different arrays to occupy large brain surface areas, we worked along the radial (z) direction by using tilted coil angles and stacking coil numbers to reduce the divergence of the emitted near field without occupying large head surface areas. The emitted electric field distributions were theoretically simulated in spherical and real human head models to analyze the depth-spread performance of proposed coils and compare with existing figure-8 coils. The results were then experimentally validated with field probes and in-vivo animal tests. Main results. The proposed ‘angle-tuning’ concept improves the depth-spread performance of individual coils with a significantly smaller footprint than existing and proposed coils. For composite structures, using the proposed coils as basic building blocks simplifies the design and manufacturing process and helps accomplish a leading depth-spread performance. In addition, the footprint of the proposed system is intrinsically small, making them suitable for multisite stimulations of inter and intra-hemispheric brain regions with an improved spread and less electric field divergence. Significance. Few brain functions are operated by isolated single brain regions but rather by coordinated networks involving multiple brain regions. Simultaneous or sequential multisite stimulations may provide tools for mechanistic studies of brain functions and the treatment of neuropsychiatric disorders. The proposed AT coil goes beyond the traditional depth-spread tradeoff rule of TMS coils, which provides the possibility of building new composite structures and new multisite TMS tools.
Spectral geometry of nuts and bolts
Authors: Boulton Lyonell , Schroers Bernd J , Smedley-Williams Kim
Published: April 2022

We study the spectrum of Laplace operators on a one-parameter family of gravitational instantons of bi-axial Bianchi IX type coupled to an abelian connection with self-dual curvature. The family of geometries includes the Taub-NUT (TN), Taub-bolt and Euclidean Schwarzschild geometries and interpolates between them. The interpolating geometries have conical singularities along a submanifold of co-dimension two, but we prove that the associated Laplace operators have natural selfadjoint extensions and study their spectra. In particular, we determine the essential spectrum and prove that its complement, the discrete spectrum, is infinite. We compute some of these eigenvalues numerically and compare the numerical results with an analytical approximation derived from the asymptotic TN form of each of the geometries in our family.
Reducing uncertainties in hydrocarbon prediction through seismic inversion
Authors: Imran Qazi Sohail , Siddiqui Numair Ahmad , Latif Abdul Halim Abdul , Bashir Yasir , Saeed Ali Almasgari A. A. , Jamil Muhammad , Ahmad Nisar
Published: April 2022

Petroleum systems in offshore are often very complex and subtle because of variety of depositional environments. Delineating a reservoir based on conventional seismic and well-log stratigraphic analysis in such complex settings often leads to uncertainties. A reliable model of reservoir can forecast the production and performance of a reservoir which can reduce the drilling risks and associated uncertainties significantly. This work is aimed to develop a new concept in reservoir modeling by integrating seismic inversion and rock physics tools. First, in order to define litho facies, rock physics modeling was carried out through well log analysis separately for each facie. Next, the available subsurface information is incorporated in a Bayesian engine which outputs the several realizations of elastic reservoir properties and their respective probabilities, which then are used for post-inversion analysis. Seismic inversion fully exploited the vast areal coverage of the seismic data and integrated it with the well logs resulted in high-resolution acoustic impedance realizations. 3D impedance models coupled with the petrophysical analysis were then used to delineate the reservoir bodies.
New approach in analysing rock property changes in vuggy carbonates
Authors: W.M.L. Sazali , S.S. M Shah , M.Z. Kashim , Z.A. Abu Bakar , B. P. Kantaatmadja , L. Knuefing , B. Young
Published: April 2022

X Field is a HPHT carbonate gas field containing about 70% of CO2, and is located in offshore East Malaysia. In order for this field to be economical and environmental friendly, PETRONAS plans to reinject produced CO2 back into the reservoir. With this objective, PETRONAS Research Sdn Bhd is conducting a feasibility study on changes of reservoir rock properties due to this CO2 sequestration activity. As the available vuggy-carbonate core-plugs have a higher risk of damage, the team employed digital core analysis (DCA) technology for this study. The study consists of three phases. In the first phase, the selected core plugs were analysed using micro CT scan and image processing software. To mimic the gas reservoir, the core plugs were then saturated with synthethic brine, before undergoing centrifuge until Sw-irr from Pc data was reached. The second phase consisted of aging the core-plugs by immersion in supercritical CO2 at pressure and temperature of the reservoir for 45 days. In the third phase the core plugs were analysed via DCA again to determine changes caused by CO2 reaction in rocks. Due to the fragility of the selected samples, they the post aging DCA analysis revealed both mechanical and geochemical changes. However, the central part of the core-plugs was not mechanically damaged and could be used to analyse the changes in porosity mainly due to geochemical reaction. Our results indicate that there will be small impact of porosity changes due to CO2 storage activity in X Field. DCA has proven to be a very useful method in determining porosity changes in reservoir rocks. Not only can DCA determine porosity of broken core plugs, but it also can extract the unbroken parts of the rock for more accurate analysis.
Major structural unconformities across Malaysia: geodynamics and basin development of Lawin, Perak
Authors: Mahmud Noor Liana , Sautter Benjamin
Published: April 2022

The first deposits overlying an unconformity may give important insights on the tectonic vertical motions and erosion processes that erased previous records. The Early Cenozoic Deposits in Peninsular Malaysia are reported to be isolated and lie unconformably on Paleozoic basement rocks. Denudation pulses from the Late Cretaceous to Eocene left the Cenozoic deposits in scarce. Stratigraphic and sedimentology studies were restricted to the availability of the resources. This study aims at providing information on the development of the early deposits from a structural perspective with the emphasis on source to sink dynamics. We interpreted the structural settings of Lawin using Digital Elevation Model (DEM) data and satellite images. Structural interpretations were cross-checked with published studies. Field observations were conducted and have been assessed through chemical and petrographic analyses. Evidence of compression and shearing are found to support interpretation. We learned that Lawin had experienced a compression and stages of extensions in its history and developed during extension. Lawin is associated to a major fault that reactivated several times, and from XRD analysis, we have illite-mica which has a close-relationship to a frequent tectonic activities and kaolinite is due to weathering. Petrography analysis were performed from SEM images and thin sections to support minerals found. Evidence of mineral fragments, iron-rich sedimentation and clay fillings were common with few kaolinite pouches. Sedimentology studies were modelled as alluvial fans. Based on DEM analysis, two different lobes are observed and on outcrop, two different angles of tilted bedding between the two lobes were measured, thus we modelled them as incised alluvial fans where the recent fan we see on DEM has extended further from abandoned lobe. Due to its tilting towards the west, we modelled them following an extensional regime.
The brittleness and ductility of shale from Setap shale, Miri, Sarawak
Authors: Baharizan Fatimah Zahrah , Ismail Mohd. Suhaili
Published: April 2022

The brittleness and ductility of Setap Shale from Bekenu, Beluru and Long Lama area can be shown by analyzing the relationship between Poisson’s Ratio and Young’s Modulus. Both Young’s Modulus and Poisson’s Ratio can be calculated using P-wave and Swave value from ultrasonic velocity test. Ultrasonic velocity analysis on core samples from Bekenu, Beluru and Long Lama shows typical values of Poisson’s ratio and static Young’s Modulus of shale. The mineral composition of samples was analyzed using X-ray diffraction (XRD). Beluru 3 was described as marl samples shows significant number of quartz and dolomite which increase the density of the rock higher than Bekenu and Long Lama area. In the other hand, the Long Lama-5 sample shows high ductility compares to other location due to high clay constituents. High clay constituents can be defined by clay constituents greater than 40% composition. The shale with more than 40% are “true shale” where it may affect the conductivity of hydraulic fracturing phase due to high ductility. High ductile shale has the ability to re-seal the fracture due to high elastic material content. The brittleness of shale shows strong relationship between the mineralogical composition of the shale at different locality of Setap Shale and its elastic properties as different samples show different mineral composition.
Potential stratigraphic traps delineation utilizing the spectral decomposition approach for RGB color blending attribute generation: a case study in the Malay Basin
Authors: Al-Masgari Abd Al-Salam , Elsaadany Mohamed , Siddiqui Numair A. , Latiff Abdul Halim Abdul , Abubakar Azli , Imran Qazi Sohai , Babikir Ismailalwali , Khan Muhammad , Adeleke Teslim
Published: April 2022

Implementing the RGB color blending attribute of the decomposed spectral has been successfully conducted for delineating the potential stratigraphic traps within the geomorphological elements of the studied interval from -1253ms to -800ms. The investigated area is situated in the peninsular Malaysia-Malay Basin and covering two neighbouring fields (Inas and Melor). Several fluvial system deposits dominate the studied interval. These interval’s time slices maps reveal several geomorphological features such as low meandering and superimposed fluvial channels system. Moreover, several structural elements and seismic artefacts are also delineated within the depositional sequences (DS-01-02) of Inas and Melor fields. The channel's sinuosity degree reflects the slope ratio of the substratum during the river's lifetime along the channel pathways. However, the low sinuosity of the main channel reflects the higher slope of the bedrock, while the high sinuousness of channels implies a lower depositional substratum slope. Validation steps have been performed utilized the gamma-ray logs signatures from several wells.
Petrophysical evaluation of Kati Formation at Seri Iskandar area, Perak, Malaysia
Authors: Salim Ahmed Mohamed Ahmed , Noh Khairul Arifin Bin Mohd , Sahari Sufizikri Bin
Published: April 2022

Non-linear relationships for shale volume estimation are designed for a specific area or formation age and most of the time they are optimistic in calculating low shale volume. This study evaluates some petrophysical properties of Late Paleozoic Kati Formation in Seri Iskandar area based on well logs and core plug samples from well CTW-01 drilled within University Teknologi PETRONAS campus. Shale volume is calculated using gamma ray log and calibrated with that obtained by sedimentation method in the lab. Porosity is determined from sonic log and calibrated with that measured in lab using Helium Porosimeter on core plugs. The shale volume equation derived from the lab analysis and well log data is Vsh = 1.0157 (IGR) - 0.0158 and achieved a correlation coefficient, R2, greater than 0.99. Shale volumes estimated from GR log using this model are in good agreement with laboratory measurements. Since the porosity is ranging between 0.5% and 2%, the reservoir rocks of the study interval are classified as tight sandstones.
Estimation of porosity from well logs and seismic using artificial neural network
Authors: Yazmyradova Gulbahar , Hermana Maman , Soleimani Hassan
Published: April 2022

The Artificial Neural Network (ANN) is widely used to map and estimate reservoir properties. Since ANN has the ability of non-linear computing and self-error correction, it serves as an alternative method to enhance reservoir characterization by improving reservoir properties' prediction. This study employed an integrated approach where seismic, and well log data are used alongside ANN to evaluate petrophysical properties in Field X, South Caspian Basin. The study field is situated in the South Caspian Basin, which developed during Tertiary-Quaternary. The South Caspian Basin covers the southern part of the Caspian Basin, coastal regions of eastern Azerbaijan, northern Iran, and western Turkmenistan. The field is geologically situated on an elongated and multi-crest, anticlinal feature, better known as Apsheron Sill. Available data set consists of log data from four wells: X1, X2, X3, X4, and 3D pre-stack seismic data. Firstly, the reservoir properties were calculated from the well log data. The simultaneous inversion was carried out to obtain elastic rock properties like the P-impedance, S-impedance, density. After that, elastic properties were used to obtain 3D dimensional SQp and SQs attributes. Furthermore, the Radial basis function Neural Network (RBFN) model was created with optional inputs: volume of P-impedance, S-impedance, density, SQp, SQs and property logs and outputs: porosity. Moreover, this research work demonstrates an application of SQp and SQs attributes for properties prediction using neural network. The neural network's primary purpose is to determine a relationship between obtained volumes and reservoir parameters, porosity at well locations. The RBFN model is successfully trained and validated on the field data. The results demonstrated an excellent correlation between actual property logs. They predicted properties, which gives confidence for spatial prediction in areas where well logs are not available.
Performance Evaluation of 1-Butyl-3-Methylimidazolium Chloride as Shale Swelling Inhibitor
Authors: Rahman Tauhidur , Negash Berihun Mamo , Moniruzzaman Muhammad , Padmanabhan Eswaran , Ato Quainoo Kwamena
Published: April 2022

Shale instability due to hydration and swelling is an unavoidable problem during hydraulic fracturing or drilling with water-based fluids. In this study, 1-butyl-3-methylimidazolium chloride (BMIMCl) an ionic liquid was utilized as a clay swelling inhibitor. The performance of BMIMCl was evaluated by the bentonite plate soaking test and linear swelling test. FT-IR and zeta potential test was done to explain the swelling inhibition mechanisms. Moreover, XRD test was conducted for the characterization of bentonite (swelling clay). 2 wt.% BMIMCl reduced the swelling rate of bentonite by 19.38% while the conventional and mostly used inhibitor, 3 wt.% KCl reduced 13.84% compared with distilled water. These results showed that BMIMCl has better inhibitive properties than the most used clay stabilizer, KCl. This inhibitor showed better performance because of the presence of a hydrophilic head and hydrophobic tail in its structure. The hydrophilic positive head helped it to get adsorbed on the bentonite surface, forming hydrogen bonds, and reduced the surface negative charge. On the other side, the butyl chain may be made a hydrophobic shield that prevented water from entering into the interlayer space. The ability of BMIMCl to form bonds with bentonite and water was confirmed by FT-IR analysis. Therefore, BMIMCl has the potential to be an effective shale swelling inhibitor during drilling and hydraulic fracturing operations in the water-sensitive shale formation.
Boundaries and lithofacies of the Kati Formation (SW Perak, Peninsular Malaysia)
Authors: Khan Muhammad Ekrahm Nawas , Vintaned Jose Antonio Gamez
Published: April 2022

Very few geological research has been undergone on the Kati formation due to its scarcity of natural outcrops and complexity. The heavily weathered and limited number of natural outcrops available around the areas of Bandar Seri Iskandar and Parit (Perak) may help to define the Kati Formation in a more clear way. After recent human construction activities, more exposures can be studied, which makes easier the process of gathering geological information. The Kati Formation inspires quite a few questions to the scientific community, such as the source of the iron oxide extensively found on it and the processes that turned a softer shale into hard concretions, the presence of trace fossils as the only palaeontological evidences preserved in this heavily replaced rock unit, and the age of the overlying quaternary deposits, which is a key for understanding, in turn, the succeeding diagenetic processes. The objective of this research is to better define the Kati Formation in relationship to their associated quaternary materials, Mesozoic granites and metamorphic rocks, all by using classical stratigraphic methods first.
Evaluation of N-ethyl perfluorooctyl sulfonamide as a thickener of supercritical carbon dioxide
Authors: Mojid Muhammed Rashik , Negash Berihun Mamo , Babatunde Kawthar A , Jufar Shiferaw Regassa
Published: April 2022

Usage of supercritical CO2 (Sc-CO2) as fracturing and displacing fluid is given much attention in recent years. It enables the prevention of issues related to hydraulic fracturing such as formation damage, clay swelling, capillary trapping, and consumption of a high volume of water. However, the low proppant carrying capacity, high frictional resistance, and fast filtration of Sc-CO2 are the challenges that require further research. Characterization of shale samples for implementation of Sc-CO2 as a fracturing fluid consists of imaging and qualitative analysis, identification of crystalline phases presents in material and determination of pore size distribution, surface area, micropore volume, porosity, and matrix density. Shale samples from Eagle Ford (EF-1. EF-2), Mancos (MC), and Wolfcamp (WF) shale formations have been characterized using field-emission scanning electron microscope (FESEM), X-Ray diffraction (XRD), surface area analyzer and porosimetry system (SAP) and Helium Porosimeter. From FESEM and EDX experiment, among all the samples, EF-1 has the highest carbon content (25.97%), EF-2 is mostly calcium dominant (33.17%) and WF has quartz having the presence of 3.37% of silicon. The existence of these elements and compounds are also validated by the qualitative and quantitative analysis of the XRD patterns. FESEM estimates that all these shale samples have the presence of mostly mesopores. Results from SAP experiment show that BJH adsorption average pore diameter of EF-1, MC and WF 30.8490, 8.5128, and 26.4318 nm respectively and it validates FESEM result. In terms of porosity, MC has the highest (7.4%), while EF-1 has the lowest (2.01%). For eradicating the problem of low proppant carrying capacity of Sc-CO2, thickening agents such as N-ethyl perfluorooctyl sulfonamide, a viscoelastic surfactant (VES) is used in this study. The molecular simulation study of N-ethyl perfluorooctyl sulfonamide to Sc-CO2 increases the viscosity of Sc-CO2.170 times than the actual viscosity of Sc-CO2. Although this an excellent result to derive yet the experimental validation of this result is needed to pave its implementation on real field scenarios.
Major, trace, and rare earth element geochemistry of black shales from Devonian Sanai Formation in Northwestern Peninsula Malaysia: implications for the depositional environment, provenance, and tectonic setting
Authors: Ibad Syed Muhammad , Padmanabhan E.
Published: April 2022

In this study major, trace, and rare earth elements (REEs) content of Sanai (SA) shales were determined by XRF-ICP-OES and ICP-MS. These results were used to probe tectonic setting, depositional environment, and provenance and of the SA Formation black shale. These black shales contain an average total organic carbon (TOC) content of 2.68 wt. %. Black shales from SA formation were deposited in the active continental margin based on ternary diagrams of La–Th–Sc and Th–Sc–Zr/10. SiO2 is rich in SA shales with avg. 59.5% while Al2O3 is the second most dominant major oxides with avg. 15.8%. Major oxides of the Western Peninsula (WP) Malaysia shale and hot shale gas reservoirs from China are also compared for the assessment. Redox element ratios infer deposition of the black shale most likely occurred in oxic to the anoxic environment. SA Formation black shales show a low Sr/Ba (< 0.5) value, indicating low salinity during the deposition. Geochemistry results indicate that the SA black shales seem to have been originated principally from the felsic source rock which might be granite in this case.
The potential of shale gas resources in Peninsular Malaysia
Authors: Owusu Esther B. , Gebretsadik Haylay Tsegab
Published: April 2022

Even though the black shales in Peninsular Malaysia covered a quarter of the total surface area and have been overlooked for their economic potential except few workers have evaluated their thermal maturity using rock-eval pyrolysis, vitrinite reflectance analysis and illite crystallinity. According to these research works, the shales have been categorized into immature, mature and overmatured successions, which in turn dictated the exploration activities of commercially viable shale gas in the onshore Peninsular Malaysia. In this work, published and unpublished data on the scattered black shales of Peninsular Malaysia were examined to assess exploration potential of shales from various stratigraphic windows. Thus, using comparative evaluation of all the thermal history plots of the black shales from Peninsular Malaysia; areas of thermally matured source rocks are identified. According to the thermal maturation assessment; the Palaeozoic black shales in the Peninsular Malaysia have minimal generative potential for economically viable source rock for hydrocarbon, whereas the younger successions of Oligocene to Miocene have considerable potential to serve as source rocks of feasible prospect, provided permissible geological settings are met.
Organic geochemical characterization of Cretaceous — Eocene shale and mudstone in Belaga Formation
Authors: Ibrahim Walaa Elnasir , Salim Ahmed Mohamed Ahmed
Published: April 2022

Sarawak Basin has been very prominence for increasing hydrocarbon potential in their formations and its nature as a source rock. Previous studies highlighting more on the evaluation of geochemical characteristics of Paleogene-Neogene coals as the source rock without taking into consideration shales and mudstones in the area. The targets of the study are to evaluate the potentiality of the hydrocarbons, the type of organic matter and thermal maturity of shales and mudstones of Belaga Formation, mainly by using data of Rock-Eval pyrolysis and vitrinite reflectance data. Twenty-one outcrops with twenty-nine samples from Belaga Formation shales and mudstones in the Central Sarawak Basin were analyzed by means of geochemical techniques. The shales and mudstones samples of the Belga Formation has low value of S2 ranging between 0.02-0.66 mg HC/g rock with an average 0.09 mg HC/g rock, indicating that the formation has poor hydrocarbon generative potential. There is lack of hydrogen-rich in the organic matter content in the Formation samples, that were affect the quality of source rocks to be evaluated as good source rock. Geochemical data (Rock-Eval) Tmax values ranging from 316 and 607°C for shales and mudstones formations and indicating various histories of maturation within the Formation. The level of the maturation is various from immature, late mature to post mature. The production index (PI) values of the studied samples in Belaga Formation ranging from 0.12-0.65 mg HC/g rock.