Gravity Values Research Articles

Suitability techniques for transforming marginal lands to support building infrastructures in parts of Rivers State, Nigeria

This study examined sustainability techniques for transforming marginal lands to support building infrastructures in parts of Rivers State, Nigeria. The study adopted the cross-sectional survey research design method employing the use of standard penetration approach utilizing Geographic Information System analysis. Marginal lands were delineated as margins of watrbodies using the polygon method in ArcGIS, and were created as a feature class for polygon data (shape file). The locations, river margins and roads formed point data, polygon data and line data respectively. Digitisation was achieved using Orthophoto Image in ArcGIS 10.0 software where seven geotechnical boreholes were located and drilled using permission rig to a depth of 10.5m in five local government areas of Rivers State. In-situ standard penetration testing and soil sampling for laboratory geotechnical properties was done using standard laboratory techniques. Findings of the analysis show that silty and sandy clay are the dominant soil within the foundation depth of 1-2.5m which are underlained by clays and sands of varying densities and grain sizes with their specific gravity value of ranges of 1.9 – 2.66 depicting that the areas are underlined by organic, diatomaceous and high porosity permeability soils deposits under water logged conditions. The cohesive strength of the soils vary from 65KN/m 2 - 115KN/m 2, angle of internal friction ranged from 0o – 10o and shear strength ranged from 110KN/m 2 – 147.46KN/m 2 and the allowable bearing capacities of 180.22KN/m 2 – 236.05KN/m 2. The stability techniques for the transformation of the land to support building infrastructures are pre-construction soil stabilization and marginal land reinforcement. The study thus recommends for building summation of consolidated techniques for sustainability of infrastructures.

Impact of the frequency error of direct digital synthesizers on the evaluation of two-photon light shift in atom gravimeters

One major systematic error for free-fall atom gravimeters is the effect of two-photon light shift (LS2). In the process of evaluating LS2, the results can be affected by the residual frequency error of direct digital synthesizers due to necessary experimental parameter changes. In this paper, the impact of the coupling effect between the frequency error and LS2 has been investigated and analyzed, along with the related physical mechanisms. The parameters of the frequency error sequence, such as the time step of δt and the time delay of Δt, significantly affect the bias and uncertainty of LS2. Notably, when these parameters are significantly altered or misaligned, the impact can reach several tens of µGal. Conversely, when they remain within the optimal ranges, the impact can be minimal. Specifically, when δt is less than or equal to 10 µs, the impact on the LS2 bias is less than 0.3 µGal, with the contribution to the total uncertainty of the gravity value being approximately 0.1 µGal. Furthermore, after correcting the phase shift introduced by the frequency error, the evaluation results have a similar improvement effect on the whole. Compared to the LS2 theoretical value, the residual is generally on the order of µGal. Through the comprehensive analysis and optimization, as well as related experiments, this cross-effect is managed and decoupled, leading to accurate LS2 evaluation results. This improvement ensures a better accuracy in the obtained absolute gravity values. The analysis methods discussed can provide an effective strategy for enhancing the performance of atom gravimeters.

Spatial distribution of remaining movable and non-movable oil fractions in a depleted Maastrichtian chalk reservoir, Danish North Sea: Implications for CO2 storage

Depleted oil and gas fields constitute potentially important storage sites for CO2 in the subsurface, but large-scale injection of supercritical (sc) CO2 in chalk has not yet been attempted. One of the risks is the adverse effect of the substantial amount of remaining oil in the chalk reservoirs on scCO2 injection. In order to counter an undesired effect on injectivity, a fundamental understanding of the spatial distribution and quantity of the movable, semi-movable, and non-movable oil, and solid bitumen/asphaltenes fractions of the remaining oil is critical. In this study a combination of organic geochemistry (gas chromatography of the saturated fraction and programmed pyrolysis), and reflected light microscopy was applied to evaluate and measure the spatial distribution, volume, and saturation of different oil fractions in a well-defined reservoir interval of a waterflooded Maastrichtian chalk reservoir in the Danish Central Graben, North Sea. A total of 127 samples from a slightly deviated vertical well and two ∼5 km-long horizontal wells from the Halfdan and Dan fields were analyzed. An original uneven distribution of oil saturation and composition or different production efficiency of different levels in the reservoir may account for variations in the total oil and oil fraction saturations. Gas chromatography shows that the solvent extractable oil is quite similar in composition, characterized by a dominance of polar compounds and a high content of asphaltenes. Extended slow heating (ESH) pyrolysis reveals that most of the remaining oil saturation consists of semi-movable oil and total non-movable oil (non-movable oil plus solid bitumen/asphaltenes). Reduced oil gravity values (API) are related to evaporation loss of the lightest hydrocarbon fraction during core storage and increase of the relative proportion of the heavier oil fractions by waterflooding during production. Microscopy disclosed three forms of oil: i) Patchy distributed lighter, movable oil showing a bluish fluorescence, ii) Brownish staining with a dark orange to brownish fluorescence, and iii) Dark brown non-fluorescing oil and black solid bitumen/asphaltenes occurring in microfossils and along deformation bands and stylolites, constituting the heavy non-movable oil fractions. There is a general correlation between bulk rock porosity and the total non-movable oil saturation. It thus appears that the heavy non-movable oil fractions preferentially occur in association with low-permeability heterogeneities within high-permeability stratigraphic intervals. These intervals appear to favor accumulation of non-movable oil and solid bitumen/asphaltenes and may carry a higher risk for impeding scCO2 flow.

Assessment of geoid models for geopotential values determination in Mexico'S continuous monitoring network

The requirements of the reference systems related to the vertical part are aimed at adopting a global height system that allows taking advantage of the development of satellite technology that provides terrestrial data with higher quality. Due to this need, the International Association of Geodesy (IAG) has proposed the realization and implementation of the International Height Reference System (IHRS), based on geopotential numbers obtained from the gravity potential difference at a point on the Earth's surface (W(P)) referred to the geoid (W0), whose value adopted by convention corresponds to 62636853.4 m2s-2. Nowadays, efforts are underway worldwide to materialize this system. Considering this, the present work entails the analysis of information gathered from SIRGAS continuous monitoring stations in Mexico: MTY2, IDGO, INEG, MERI, and ICAM, to estimate its gravity potential from sufficiently precise geocentric coordinates and absolute gravity values, which when combined with heights derived from geoid models, allows obtaining a modern height system such as the IHRS. The analysis aims to evaluate the feasibility of estimating the gravity potential at the stations, by using precise geocentric coordinates and absolute gravity values which when combined with high-resolution geoid models such as EGM2008, GGM10, EIGEN6C4, XGM2019e_2159, SGGUGM2, and the xGEOID20B, to implement a modern height reference system in Mexico; as well as to contribute to the International Height Reference Framework (IHRF), which in its latest version only includes the MERI station, located in Mérida, Yucatán. Therefore, we consider that for their characteristics the stations analyzed can be included to densify the frame in the implementation of the system. The results show the differences in gravity potential in the different regions of the country, reinforcing the need to consider more reference stations. Additionally, benchmark points close to the selected stations were analyzed to determine the reference potential value of the GGM10, with which it was also possible to analyze the behavior between the observed geoid and the different geoid models, toward the modernization of the official height system, which is based on orthometric heights called NAVD88, which shows us the differences between the geoid observed with the official height system and the analyzed models. Finally, the study examines the consistency of the calculated orthometric heights with geopotential numbers derived from the different geoid models.

Tectonics of Cauvery basin (India) in onshore and offshore portions

Morphometric studies coupled with geophysical investigations from petroliferous basins provide valuable information about tectonics of the regions. We deduce six morphologic parameters from the River Cauvery's designated (sub)watersheds and perform dendrogram clustering analysis. The main channels of the (sub)watersheds showcase steeper gradient and meandering nature with less concavity. On the other hand, the distributaries portray lesser gradient and straight nature with greater concavity. From the offshore region of the Cauvery basin, we perform gravity modeling. The results show variations in gravity values from low to high, -150 to 50 mGal probably because of the basement ridge-depression features. This anomaly orientation indicates the extension of the sub-basin in the region. A strong NE-SW gravity trend possibly suggests a high-density plug at mid-crust. The low gravity values near the Vedaranyam region indicate low-density rocks within the basement. Places of high gravity anomaly show a decrease in bathymetry depth and vice versa. This indicates isostatic compensation of the Moho geometry, possibly due to crustal thinning in the offshore areas. Isostatic regional gravity fields are manifested by Moho relief and can have implications on the lithospheric mechanical strengths. Bathymetric studies indicate multi-directional slopes. Relatively flat areas can indicate depocenters. E-W trending lineaments mapped on the Precambrian basement from a portion of the study area is presumably a manifestation of Cauvery Shear zone, which also persists in the offshore region.

Hamiltonian Birkhoff Normal Form for Gravity-Capillary Water Waves with Constant Vorticity: Almost Global Existence

We prove an almost global existence result for space periodic solutions of the 1D gravity-capillary water waves equations with constant vorticity. The result holds for any value of gravity, vorticity and depth, a full measure set of surface tensions, and any small and smooth enough initial datum. The proof demands a novel approach—that we call paradifferential Hamiltonian Birkhoff normal form for quasi-linear PDEs—in presence of resonant wave interactions: the normal form is not integrable but it preserves the Sobolev norms thanks to its Hamiltonian nature. A major difficulty is that paradifferential calculus used to prove local well posedness (as the celebrated Alinhac good unknown) breaks the Hamiltonian structure. A major achievement of this paper is to correct (possibly) unbounded paradifferential transformations to symplectic maps, up to an arbitrary degree of homogeneity. Thanks to a deep cancellation, our symplectic correctors are smoothing perturbations of the identity. Thus we are able to preserve both the paradifferential structure and the Hamiltonian nature of the equations. Such Darboux procedure is written in an abstract functional setting applicable also in other contexts.

Development of Nanofluid-Based Solvent as a Hybrid Technology for In-Situ Heavy Oil Upgrading During Cyclic Steam Stimulation Applications.

This paper evaluates solvent-based nanofluids for in situ heavy oil upgrading during cyclic steam stimulation (CSS) applications. The study includes a comprehensive analysis of the properties and characteristics of nanofluids, as well as their performance in in situ upgrading and oil recovery. The evaluation includes laboratory experiments to investigate the effects of the nanoparticle's chemical nature, asphaltene adsorption and gasification, heavy oil recovery, and quality upgrading. The results show that alumina-based nanoparticles have a higher efficiency in asphaltene adsorption and catalytic decomposition at low temperatures (<250 °C) than ceria and silica nanoparticles. Specifically, alumina nanoparticles achieved asphaltene adsorption of 48 mg g-1, while ceria adsorbed 42 mg g-1. Alumina and ceria required around 90 and 135 min for 100% asphaltene conversion. Nanofluids were designed by varying nanoparticle and surfactant concentrations dispersed in naphtha, obtaining that the nanofluid containing 0.05 wt % of nanoparticles and 0.05 wt % of surfactant presents the highest yield in increasing API gravity by 5° and reducing oil viscosity by 90% in thermal experiments. Finally, the nanofluid was evaluated under dynamic conditions. The results show that nanofluid-based solvents can significantly improve the recovery and upgrading of heavy oil during CSS applications. When the steam injection technology was assisted by naphtha and nanofluid, 64% and 75% of the original oil in place were recovered, respectively. The effluents obtained in each stage presented lower API gravity values and higher viscosities for those obtained without a nanofluid. Specifically, the API gravity of the recovered oil rose from 11.9° to 34°, and the viscosity decreased to below 100 cP. The paper concludes by highlighting the potential of nanofluid-based solvents as a promising technology for heavy oil recovery and upgrading in the future.

Effect of government environmental attention on green transformation: Empirical analysis from a spatiotemporal perspective in China

As the primary policymaker and implementer, the government plays an essential role in driving regional green transformation development (GTD). The study of the impact mechanisms of government environmental attention (GEA) on GTD can offer a scientific basis and reference for policy-making and regional governance. However, the varying focus of local governments on environmental issues and the externalities of environmental governance underscore the complexities in the influence of GEA on GTD. This paper proposes a method that integrates multi-source data to explore the impact of GEA on GTD from a spatiotemporal perspective. A text mining framework is first proposed to provide a more accurate measurement of the GEA, and the geographically and temporally weighted regression model is used to analyze the spatiotemporal characteristic and mechanism of GEA's impact. Additionally, the spatial correlation effect is explored based on the gravity model. The results indicate that the level of GTD in China demonstrates an increasing trend with an average annual growth rate (AAGR) of 3.22%, while the variance between provinces is also increasing. GEA has a significant positive effect on GTD (R2 = 0.866), with an average growth rate of 18.1% following the implementation of major environmental policies. The spatial distribution pattern of GEA's impact shows the characteristics of “central > eastern > western > northeastern”. GEA promotes GTD by increasing environmental governance expenditure and enhancing public environmental services, while the transmission pathway of promoting green innovation has not yet worked. The spatial correlation and spillover effects of GEA have shown an overall increasing trend, with the AAGR of 8.92% in the gravity value. Inter-provincial cooperation can promote GTD, and certain collaborative clusters among provinces have been formed. This paper provides novel insights into the theoretical connection between GEA and GTD. The research findings can serve as a reference for the government to propose targeted policies for promoting regional green transformation.

The effect of different salt concentration in physical nature preparation of face scrub gel Caulerpa racemosa

Abstract Facial skin that is often exposed to sunlight can experience a disturbance in the balance of the skin so that the skin’s moisture decreases and the skin becomes dry and dull and there is an accumulation of dead skin cells. Therefore, a treatment is needed to get healthy facial skin by using cosmetic preparations such as face scrubs as exfoliate cleansers. The use of Caulerpa racemosa seaweed in face scrub gel preparations is used as a producer of agar which acts as a gel former in face scrub gel preparations and the use of salt as a scrub which removes dead skin cells (exfoliating). The purpose of this study was to determine the effect of adding salt on the physical properties of the Caulerpa racemosa face scrub gel preparation. The results of the research that has been done shows that salt has a significant effect (p &lt;0.05) on the physical properties of the Caulerpa racemosa face scrub gel preparation. Appearance of the Caulerpa racemosa face scrub gel for each homogeneous treatment. Specific gravity and viscosity values are close to SNI standards. The face scrub gel has a pH of 6 and does not cause irritation and based on appearance, smell and color parameters it shows the best results by adding 30% salt to the Caulerpa racemosa face scrub gel.

Validation analysis of a method for determining the ship’s vertical centre of gravity and moment of inertia based on the model test

ABSTRACT Given the necessity for numerical validation, precisely determining the ship’s center of gravity and moment of inertia is crucial for validating simulations with motions. This paper performs three sections to illustrate the accuracy of the measurement method based on SolidWorks. Firstly, an analytical formulation on a shelled box is used to do the verification analysis. Secondly, the inclining test is used to validate the reliability of the measurement method in determining the ship's vertical center of gravity. By comparing the vertical center of gravity value in the test, SolidWorks yields only a 4.06% error. Thirdly, the flooding test of the damaged ship in still water is used to validate the reliability of the measurement method in determining the ship's moment of inertia. By comparing the test roll curve and its amplitude of 5.5 degrees, the tendency consistency and 3.6% amplitude error validate the moment of inertia input into CFD software.

Effect of Organic and Industrial Fertilizers on Reducing Sugar, Specific Gravity, Dry Matter and Starch Composition of Fresh Harvested Irish Potato Varieties in Musanze District Rwanda

Potatoes for use in industrial processing must have a low reducing sugar concentration. This study investigates the impact of organic and synthetic fertilizers on the composition of Irish potato cultivars’ reducing sugar, specific gravity, dry matter, and starch. The research was conducted at Busogo Farm in Rwanda, using randomized complete block designs in seasons 2021 B and 2022 A with rate of ten tones per hectare under the doses of 100%, 50%, and 0% and three hundred kilograms per hector under the dose of 100%, 50% and 0% respectively for farmyard manure and NPK 17.17.17. Results showed significant effects of season and treatment on reducing sugar levels in potatoes. Twihaze and Kirundo varieties recorded high glucose (0.09%), while Gisubizo variety in control, recorded low glucose (0.01%). Additionally, the analysis of variance showed that Irish potato varieties with low to moderate and moderate to high glucose contents, respectively, experienced extremely significant (p 0.001) effects of farmyard manure and NPK on glucose content for the seasons 2021 B and 2022 A. The application of inorganic and organic fertilizers had a significant impact (p 0.05) on dry matter in seasons B and A, according to the analysis of variance. Additionally, the results demonstrated extremely significant (p&lt;0.01) differences in specific gravity and starch in both seasons, with Kinigi variety having higher values of dry matter, specific gravity, and starch content in season B and A, respectively, of 24.58, 1.10, and 18.59%. Season 2022 A’s high decreasing sugar levels were caused by meteorological conditions brought on by the soil’s high moisture content as well as the maturity of the tubers. Due to its low level of reducing sugar, Gikungu, Kirundo, and Kinigi are excellent for chips whereas Twihaze variety is advised for boiling cooking methods.

Influence of temperature and heating duration on the thermal stability and flow characteristics of oil extracted from undersized crawfish (Procambarus clarkii) using non‐solvent method

AbstractUndersized crawfish (UC) have less economic value for sale in live or processed tail meat markets. Therefore, this study's objectives were to extract crawfish oil (CO) from UC and determine the impact of temperature and heating duration on CO's thermal stability and flow properties. However, extracting oil from these undersized specimens could potentially add value to the crawfish industry. Crawfish minced meat (CMM) was obtained by passing cooked and chilled UC through a pilot scale deboning machine. CO was extracted by agitating CMM at 70°C for 30 min, followed by centrifugation at 10,000×g. CO was analyzed for inherent physicochemical characteristics, heating time (0–8 h), temperature (45–85°C) effects on peroxide value (PV) and astaxanthin (ASX) content, and flow properties at 5–35°C. ASX content, PV, water activity, bulk density, specific gravity, and free fatty acid values in CO were found to be 1.52 ± 0.06 mg/g oil, 0.22 ± 0.07 meq/kg, 0.56 ± 0.02, 0.88 ± 0.00, 0.90 ± 0.00 g/mL, and 0.11 ± 0.04%, respectively. ASX content in CO showed no significant change within or between same‐temperature and different‐temperature heated samples after 8 h. PV increased significantly from 0 to 8 h of heating at all tested temperatures (45, 65, and 85°C; Δ = 0.31, 0.51, and 10.76 meq/kg, respectively). CO had pseudoplastic characteristics below 30°C and Newtonian flow from 30 to 35°C. The Arrhenius equation suitably described the relationship between temperature and apparent viscosity of CO. This study characterized a seldom‐researched oil (CO containing ASX) and provided insight into its ability to resist thermal degradation.

Physico-chemical characterization of cupola slag: Enhancing its utility in construction

Cupola slag is a waste material of the steel and iron industries. Its composition is determined by the cupola furnace and other elements used in steel and iron manufacturing. This paper investigates the characterization behavior of various cupola slag materials. As a result, x-ray fluorescence (XRF), x-ray diffraction (XRD), thermogravimetry differential thermal analysis, and scanning electron microscopy (SEM) methods were used to characterize three cupola slag samples from distinct origins. In addition, various physical properties were used to compare different cupola slags. The specific gravity values of CS-1 (cupola slag-1 sample), CS-2 (cupola slag-2 sample), and CS-3 (cupola slag-3 sample) are 1.36, 2.5, and 2.917, respectively. The density and water absorption for CS-1, CS-2, and CS-3 are 1414.86, 1477.71, and 1796 kg/m3, and 0.37%, 0.32%, and 0.26%, respectively. Cupola slag also includes a larger percentage of lime, according to XRF data, which contributes to its improved binding characteristics. A higher calcium oxide content in CS-3 could facilitate the pozzolanic process. The presence of angular particles that aid in material binding is seen in the SEM image. Compounds with a nanostructure are then flawlessly blended into the mixture and grouped with calcium alumina silicates formed by cement hydration. The XRD pattern of cupola slag exhibits high peaks, indicating that the material is crystalline in character and can be utilized as sand. It also shows the presence of other chemical compounds, such as silica, which ranges from 30% to 45%. CS-1 and CS-2 have comparable XRD patterns. However, CS-3 has a somewhat different pattern because of the greater CaO content. Weight loss begins at higher temperatures, which shows that the material is stable at higher temperatures, according to a thermo-gravimetric study. The differential thermal analysis curve of CS-3 indicates that the material remains stable up to a temperature of 600 °C. The physical characteristics of all cupola slag samples show that cupola slag may be utilized to make sustainable building materials because of its lower specific gravity, density, and water absorption.

Application of hydrostatic local thermodynamic equilibrium atmosphere models to interpretations of supersoft X-ray source spectra

Supersoft X-ray sources (SSSs) are accreting white dwarfs (WDs) with stable or recurrent thermonuclear burning on their surfaces. High-resolution X-ray spectra of such objects are rather complex, often consist of several components, and are difficult to interpret accurately. The main emission source is the hot surface of the WD and the emergent radiation can potentially be described by hot WD model atmospheres. We present a new set of such model atmosphere spectra computed in the effective temperature range from 100 kK to 1000 kK, for eight values of surface gravity and three different chemical compositions. These compositions correspond to the solar one as well as to the Large and Small Magellanic Clouds, with decreased heavy element abundances, at one-half and one-tenth of the solar value. The presented model grid covers a broad range of physical parameters and, thus, it can be applied to a wide range of objects. It is also publicly available in XSPEC format. As an illustration, we applied it here for the interpretation of Chandra and XMM grating spectra of two classical SSSs, namely, CAL 83 (RX J0543.5–6823) and RX J0513.9–6951. The obtained effective temperatures and surface gravities of Teff ≈ 560 kK, log g ≈ 8.6–8.7, and Teff ≈ 630 kK, log g ≈ 8.5–8.6, respectively, are in a good agreement with previous estimations for both sources. The derived WD mass estimations are within 1.1–1.4 M⊙ for CAL 83 and 1.15–1.4 M⊙ for RX J0513.9–6951. The mass of the WD in CAL 83 is consistent with the mass predicted from the respective model of recurrent thermonuclear burning.

3D Gravity and magnetic inversion modelling for geothermal assessment and temperature modelling in the central eastern desert and Red Sea, Egypt

The Central Eastern Desert and Red Sea region have emerged as a significant area of interest for geothermal energy exploration, owing to their unique geological characteristics and active tectonic activity. This research aims to enhance our understanding of the region's geothermal potential through a comprehensive analysis of gravity and magnetic data. By utilizing a 3D gravity inversion model, a detailed examination of subsurface structures and density variations was conducted. Similarly, a 3D magnetic inversion model was employed to investigate subsurface magnetic properties. Integration result from the Pygimli library ensured robustness and accuracy in the inversion results. Furthermore, a temperature model was developed using the WINTERC-G model and inversion techniques, shedding light on the thermal structure and potential anomalies in the study area. The analysis of the Bouguer gravity map, 3D gravity inversion model, and magnetic data inversion yielded significant findings. The Red Sea exhibited higher gravity values compared to the onshore Eastern Desert, attributed to the presence of a thinner and denser oceanic crust as opposed to the less dense continental crust in the Eastern Desert. The 3D gravity inversion model revealed distinct variations in density, particularly high-density zones near the surface of the Red Sea, indicating underlying geological structures and processes. Conversely, density gradually decreased with depth along the onshore line, potentially influenced by a higher concentration of crustal fractures. The magnetic data inversion technique provided additional insights, highlighting areas with demagnetized materials, indicative of elevated temperatures. These findings were consistent with the correlation between high-density areas and low magnetic susceptibility values, reinforcing the proposition of increased heat transfer from the Red Sea. Comparative analysis of temperature profiles further confirmed the presence of elevated temperatures in promising zones, emphasizing the geothermal potential associated with heat transfer from the Red Sea.This research contributes to the understanding of the geothermal resources in the Central Eastern Desert and Red Sea region. The results from gravity and magnetic data inversions, combined with temperature profiles, provide valuable information for future geothermal exploration and utilization efforts. The findings underscore the importance of geothermal energy in achieving sustainability and contribute to the global discourse on renewable energy sources.

Turunan Radial dari Anomali Gravitasi untuk Identifikasi Injeksi Air pada Reservoir

Time Lapse micro-gravity or 4D microgravity has been developed and applied for various purposes related to the dynamics change beneath the earth's surface. The principle is a repeated and periodic measurement to determine the change in gravity value at time interval as a yield of the dynamics changes in the density change of the subsurface. This method can be used for monitoring and identify water or gas injections in reservoirs. Mass density taht changes due to gas injection provide changes in the values of gravity over time. This change allows us to identify the dynamics of gas movement in reservoir. A reservoir model has been made in this research with gas injected in reservoir bulk. The time lapse gravity respons value is calculated numerically. Oil-gas contact is an edge between gas injection front with oil which move direction away from injection point. The first and second radial derivatives of 4D gravity can provide as a front of the gas movement in the reservoir. A radial derivatives is a horizontal derivative of gravity anomaly along radial direction from a point which selected as a entre of the anomaly. The second radial derivative is derivative of radial deriative. Radial derivatives value of this model response have range of 20 microGals/m and second radial derivative has a values of 0.05 microGals/m2. Graphics of absolute value of radial derivative and second radial derivative of 4D gravity anomaly seemingly correlated with the oil-gas contact of reservoir models. Radial derivative and second radial derivative has been proven as new available method wich has ability to shows a boundary of a horizontal layer with vertical density contrast. Keywords: Radial derivatives, reservoir, gas injection.

Study of the variation in the value of gravity resulting from basalt intrusions in the area of Massallata and its surroundings using Bouguer gravity anomaly maps

In this paper an attempt to locate the sites of basalt intrusion, an analysis and study of Bouguer map was carried out for the area, which lies between two circles of width 32,250 - 32,360 north, and between longitudes 14.30 - 13.49 east. The paper included processing the gravity data and separating the gravity anomaly from each other using the derivatives method Interpretation of gravity data was performed using the modeling program (2D, 3D), which aims to create a geological profile that shows the third dimension of the distribution of different rocks, and rather olivine and phenolitic basalt intrusions in the study area depending on the vertical distribution of density, which is reflected in the values of the gravity anomalies in the contour map of the region. Basalt does not have wide openings in the study area, but it is found in the form of dikes in irregularly sprawling areas, especially those that are considered areas of sculpture by the action of running water in the valleys As for the southeastern region of the study area, olivine basalt rocks were found at a depth of 3 - 5 meters, and they are deaf, which indicates their crystallization under the surface of the earth, especially in the area of the Tarhuna agricultural project. Keywords: Basalt intrusions, Bouguer gravity anomaly, Geological profile, Rock density.

Effect of sodium benzoate on Lemon Grass (Cymbopogon citratus) ice tea

Sodium benzoate is commonly used as a food preservative to prevent deterioration. According to USEPA standards, the allowable maximum for sodium benzoate in beverages is 0.15%, and 0.13% in fruit juice. A high sodium benzoate intake can induce a variety of illnesses in humans. The current study analyzes the influence of various sodium benzoate concentrations on final product quality. The product was tested to evaluate its physiochemical, proximate, and sensory properties. Acidity, pH, specific gravity, and antioxidant characteristics were identified. The product with the least amount of Na-benzoate performed better than the products with a higher amount of sodium benzoate. Products with 0.06 and 0.07% sodium benzoate were disliked due to a pungent aftertaste, whereas products with 0.05% sodium benzoate were preferred. In terms of physicochemical parameters, all treatments had similar brix, pH, acidity, specific gravity, and antioxidant values. The proximate analyses were also found same for all three treatments. Bangladesh J. Sci. Ind. Res. 59(2), 123-128, 2024

Feasibility of Treated Sand Brick Waste with Silica Fume Based Geopolymer for Coarse Aggregate Application

Construction and demolition waste (CDW) management should focus on reducing CDW or properly recycling the materials since this waste is now a global problem. Sand brick waste, a component of a building’s structure, is one type of CDW. To be used as recycled aggregate, these wastes are invariably categorised as low grade. Due of the improved qualities provided, geopolymer research has recently become more popular. The objective of this study is to investigate the physical and mechanical properties of recycled sand brick aggregate (RSB) treated with silica fume based geopolymer coating. Additionally, the effectiveness of the treated RSB will be applied in concrete as coarse aggregate. The sample was made using a solid-to-liquid ratio of 1.0, 1.2, 1.4, 1.6, and 1.8. At 2.5 and 10 M, alkaline activator is a constant variable. Testing of specific gravity, water absorption, and aggregate impact value were analysed. The treated RSB concrete will then be evaluated against normal concrete. In terms of density, water absorption, and compressive strength, natural concrete performs better than treated RSB concrete. In comparison to natural concrete, treated RSB concrete absorbs 5.8% more water. Treated RSB concrete has a density of 1815 kg/m3, compared to natural concrete’s 2080 kg/m3. The compressive strength of concrete made using treated RSB aggregate is 18.1 MPa after 7 days, and 27.1 MPa at 28 days. The testing revealed that the treated RSB aggregate concrete met the specifications. As a result, treated RSB aggregate concrete offers an advantage over natural OPC concrete while saving the environment.

Boosting biodiesel production from waste vegetable oil water using Acid-Base Sequential Catalysis

&lt;p&gt;The use of active and recyclable catalysts is advantageous for catalytic biodiesel synthesis from waste vegetable oils which is in demand owing to frequent calls on environmental pollution and for clean renewable energy production. For this study, homogenous catalysts are effective at converting single-origin feedstocks low in free fatty acids (FFA) and water into biodiesel. Biodiesel production based on waste vegetable oil was carried out to establish an optimal catalyst régime. Acid-catalyzed transesterification and sequential base catalysis were used to convert waste vegetable oil to biodiesel at varying amounts of catalyst (0.46-0.58%) and different contact times (1-2 hr). Optimal yields were obtained at 2 hrs contact time and 0.50% amount of catalyst. Characterization tests conducted were specific gravity (0.8718-0.8935), flash point (117-1370C), viscosity (4.29-6.09mm2/s) and cetane index (40-43) values were within biodiesel specifications. The study, therefore, confirmed that acid-base sequential catalysis holds a lot of promise for the creation of affordable, environmentally friendly technologies. The biodiesel's characteristics were also in good agreement with American (ASTM D6571) fuel specifications. Therefore, the work recommends the utilization of acid (H2SO4) and base (NaOH) catalysis in the technologically enhanced conversion of waste vegetable oil into biodiesel.&lt;/p&gt;