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Gradiently denitrated gun propellant (GDGP) prepared by a “gradient denitration” strategy is obviously superior in progressive burning performance to the traditional deterred gun propellant. Currently, the preparation of GDGP employed a tedious two-step method involving organic solvents, which hinders the large-scale preparation of GDGP. In this paper, GDGP was successfully prepared via a novelty and environmentally friendly one-step method. The obtained samples were characterized by FT-IR, Raman, SEM and XPS. The results showed that the content of nitrate groups gradiently increased from the surface to the core in the surface layer of GDGP and the surface layer of GDGP exhibited a higher compaction than that of raw gun propellant, with a well-preserved nitrocellulose structure. The denitration process enabled the propellant surface with regressive energy density and good progressive burning performance, as confirmed by oxygen bomb and closed bomb test. At the same time, the effects of different solvents on the component loss of propellant were compared. The result showed that water caused the least component loss. Finally, the stability of GDGP was confirmed by methyl-violet test. This work not only provided environmentally friendly, simple and economic preparation of GDGP, but also confirmed the stability of GDGP prepared by this method.

This work shows the technical feasibility to obtain uranium tetrafluoride through an electrochemical mercury cell. This technique represents a custom scaling-up methodology from our previous studies to obtain UF4 using the dropping mercury electrode cell. The UF4 products were obtained from natural UF6 gas, which was hydrolyzed to obtain a 50 g/L UO2F2 solution. The electrolysis cell was made using a mercury reservoir, to reach UF4 production rates of 1 Kg UF4/day. This custom design allowed a stable UF4 production thanks to the mercury cathode, which do not permit the accumulation of solid products in its surface. The cell was tested using current densities from 5.000 to 17.500 A/m2 and temperatures from 25 to 65 °C. The maximum current efficiency achieved under these conditions was 80%. The UF4 powders possessed spherical morphology, with diameters between 20 – 80 μm. Compared to the SnCl2 precipitation, this process did not allow preferential growth of the precipitates. This improved the compaction of the UF4 – Mg powders mixtures, with densities between 3.0 – 3.5 g/cm3. The purity of the UF4 products was over 98%.

The horizontal distribution and periodic accumulation of hydrocarbon in reservoirs are well understood. However, our understanding on the vertical distribution of hydrocarbon accumulation in reservoirs is not clear and remains mysterious to some extent. We proposed a concept of hydrocarbon accumulation depth limit (HADL) to characterize the hydrocarbon’s vertical distribution in petroliferous basins, which is determined by statistical analyses of the variation trends of reservoir layers’ essential properties, including hydrocarbon saturations (So), movable hydrocarbon ratios (Mo) and dry layer ratio (Ko), when the depth is increased. A total of 80,762 drilling results from 12,237 exploration wells in six representative petroliferous basins in China were collected and analyzed. The reservoir layers’ essential properties So, Mo and Ko and their correlations with porosity, permeability, pore throat radius and thermal evolution degree were investigated. The critical values of So, Mo and Ko that define HADL were quantified to be So=0, Mo=0 and Ko=100. Our study indicates that the HADL in petroliferous basins varies from less than 3,000 m to more than 13,000 m deep, depending on the hydrocarbon composition, reservoir lithology, reservoir age, geothermal gradient, tectonic movement, etc. Two factors play an essential role in the formation and variation of HADL: 1) the depletion of hydrocarbon generation potential of source rocks which cuts off hydrocarbon contribution for reservoirs formation and 2) the termination of differential compaction which eliminates capillary pressure difference between the outer surrounding rocks and inner reservoir layers, ending the dominant driven force for hydrocarbon migration and accumulation in deep and tight reservoir layers. All proven oil reserves of 33.95 billion tons equivalent in China, as well as world’s discovered 52,926 oil and gas reservoirs and their unproved potential resources, are distributed above the HADL we defined.

A B S T R A C T This laboratory study examines the potential use of an anionic polyacrylamide (PAM)-based material as an environmentally sustainable additive for the stabilization of an expansive soil from South Australia. The experimental program consisted of consistency limits, sediment volume, compaction and oedometer cyclic swell–shrink tests, performed using distilled water and four different PAM-to-water solutions of PD = 0.1 g/L, 0.2 g/L, 0.4 g/L and 0.6 g/L as the mixing liquids. Overall, the relative swelling and shrinkage strains were found to decrease with increasing number of applied swell–shrink cycles, with an ‘elastic equilibrium’ condition achieved on the conclusion of four cycles. The propensity for swelling/shrinkage potential reduction (for any given cycle) was found to be in favor of increasing the PAM dosage up to PD = 0.2 g/L, beyond which the excess PAM molecules self-associate as aggregates, thereby functioning as a lubricant instead of a flocculant; this critical dosage was termed ‘maximum flocculation dosage’ (MFD). The MFD assertion was discussed and validated using the consistency limits and sediment volume properties, both exhibiting only marginal variations beyond the identified MFD of PD = 0.2 g/L. The accumulated axial strain progressively transitioned from ‘expansive’ for the unamended soil to an ideal ‘neutral’ state at the MFD, while higher dosages demonstrated undesirable ‘contractive’ states.

Materials, with high strength applications, are always high in demand for the industry. Metal matrix composites play an important role in providing these materials. In the present study, Aluminium (Al)-graphene nanoplatelets (GNP) nano composites (Al-GNP) were fabricated through the route of powder metallurgy. Pure Al was used as matrix material and GNP (C-750) was used as reinforcement. The process consists of different steps viz dry ball milling followed by compaction and sintering. Compression and hardness test were performed on the formed samples. Four types of composites were fabricated with different proportions of GNP (0.1 wt%, 0.25 wt%, 0.5 wt% and 1 wt%) and the results were compared with pure Al made with the similar process. Morphological characterization like XRD, SEM and FTIR of the formed samples was also performed. It was found that both the hardness and compressive stress were increased up to a certain proportion of GNP in Al-GNP. The maximum hardness achieved was 23 HV with 0.25 wt% GNP which was 98.2 % more than the hardness value of pure Al. Similarly, the maximum compressive stress achieved was 109.33 MPa which was 59.18% high than the compressive stress of pure Al.

Carbon nanotubes reinforced copper-based composites (Cu/CNTs) had excellent physical properties and were widely used in industrial production and manufacturing. In this work, the mechanical properties and micro morphology of Cu/CNTs composites prepared by electromagnetic powder compaction (EMPC) at 25–200 °C were investigated. Results showed that the relative density, hardness and compressive stress of Cu/CNTs compacts gradually increased as the temperature increased. The growth trend had an obvious turning point at 150 °C. The maximum relative density and compressive stress were 95.74% at 200 °C and 520.95 MPa at 150 °C, respectively. The micro morphology of the end faces and cross sections became denser. The temperature had a weakening effect on the compressive strain, but the opposite was true for compressive stress. The optimal temperature was 150 °C. The relationships between temperature and compressive stress and strain of Cu/CNTs composites were revealed.

Mechanical properties of recycled concrete aggregates (RCA) such as compaction and California bearing ratio (CBR) are important for application as unbound road base and subbase materials. Limited studies, however, have examined the effects of the nominal maximum particle diameter (Dmax) of aggregates and fines content (Fc

Analyzes of diagenetic processes that acted on the sandstones of the Iborepi Formation were performed on samples of rocks from the Lavras da Mangabeira Basin. The petrology and the diagenesis of these sandstones is little known, mainly regarding the diagenetic processes that acted on the original porosity of these rocks that can be studied as analogues of oil basin reservoirs. Petrological and petrographic studies were carried out on nine slides in order to assess the diagenetic processes that impacted the original porosity of Iborepi sandstones. The processes found were: clay infiltrated as cuticles involving grains and interstitial microcrystalline aggregates; compaction generating fractures in grains, pseudomatrix in ductile lithoclasts, bent micas, and dissolution of grains resulting in concave-convex and sutured contacts; growth precipitation secundary (overgrowths) and projections of quartz (outgrowths), kaolinite, smectite and chlorite; alteration and replacement of potassium, muscovite and biotic feldspar by kaolinite, illite and chlorite. The porosity of these rocks is predominantly intergranular, with an average of 14%, but secondary porosity occurs due to fracture and dissolution of primary grains and shrinkage of clay. In general, the primary porosity of Iborepi sandstones was reduced mainly by clay cementation, mechanical and chemical compaction, and clay infiltration, impacting its quality as a hydrocarbon reservoir. Keywords: Sandstones, porosity, reservoir. Se efectuó el analises de procesos diageneticos que actuaron sobre areniscas de la Formación Iborepi, siendo realizadas en muestras de rocas de la Cuenca Lavras de Mangabeira. La petrología y diagénesis de estas areniscas es poca conocida, principalmente cuando los procesos diagenéticos que actuaron sobre la porosidad original de esas rocas que pueden ser estudiadas como análogas de reservorios de cuencas petrlíferas. Estudios petrológicos y petrográficos fueron desarrollados en nueve laminas, a fin de validar los procesos diageneticos que impactaron la porosidad original de las areniscas Iborepi. Los procesos encontrados fueron: arcilla infiltrada como cutículas envolviendo granos y agregando micro-cristalinos intersticiales; compactación mecanica y química generando fracturas en granos, pseudo-matriz en litoclastos dúctil, micas dobladas y disolución de granos originando contactos concavo-convexo y saturados; precipitando de crecimiento y proyecciones de cuarzo, caolinita, esmectita y clorita; alteración y substitución de feldespato de potasio, moscovita y biótico por caolinita, ilita y clorita. La porosidad de esas rocas es predominantemente primaria intergranular, con medida de 14%, no obstante, tambien ocurre porosidad secundaria por la fractura y disolucion de granos primários y contraccíon de arcilla. De modo general, la porosidad primaria de arenisca Iborepi fue reducida principalmente por cimentación, compactacíon mecanica y química, y infiltación de arcilla, impactando su calidad como reservatório de hidrocarburos. Palabras claves: Areniscas, porosidad, reservorio. Análises de processos diagenéticos que atuaram sobre os arenitos da Formação Iborepi foram realizadas em amostras de rochas da Bacia Lavras da Mangabeira. A petrologia e a diagênese desses arenitos é pouco conhecida, principalmente quanto aos processos diagenéticos que atuaram sobre a porosidade original dessas rochas, que podem ser estudadas como análogos de reservatórios de bacias petrolíferas. Estudos petrológico e petrográfico foram realizados em nove lâminas, a fim de avaliar os processos diagenéticos que impactaram a porosidade original dos arenitos Iborepi. Os processos encontrados foram: argila infiltrada como cutículas envolvendo grãos e agregados microcristalinos intersticiais; compactação mecânica e química gerando fraturas em grãos, pseudomatriz em litoclastos dúcteis, micas dobradas e dissolução de grãos originando contatos côncavo-convexos e suturados; precipitação de crescimentos secundários (overgrowths) e projeções de quartzo (outgrowths), caulinita, esmectita e clorita; alteração e substituição de feldspato potássico, muscovita e biótica por caulinita, ilita e clorita. A porosidade dessas rochas é predominantemente primária intergranular, com média de 14%, porém, ocorre porosidade secundária por fratura e dissolução de grãos primários e encolhimento de argila. De modo geral, a porosidade primária dos arenitos Iborepi foi reduzida principalmente por compactação mecânica e química, ciemntação e infiltração de argila, impactando sua qualidade como reservatório de hidrocarbonetos. Palavras-chave: Arenitos, porosidade, reservatório.

Alluvial soils can be defined as sediments that have not completed their geological formation have high void ratios, low bearing capacity, and low shear strength. To eliminate the unfavorable properties, various improvement methods can be applied, such as injection, compaction, and mixing. Polypropylene fibers, a kind of geosynthetic, are used to improve the geotechnical properties of soil. In this study, the shear strength characteristics of natural and polypropylene-reinforced alluvial soils were investigated. Firstly, the index properties were examined, the materials were classified, and an idealized soil profile was constituted. Afterward, direct shear experiments were conducted with loose and dense prepared, natural, and 0.5% and 1% polypropylene fiber–reinforced alluvial soils. To investigate the effect of density on shear strength, loose and dense samples were prepared at their liquid limits. The direct shear, test results showed that the dense prepared natural and polypropylene-reinforced samples had higher internal friction angles than did the loose samples. The density had a greater effect on the friction angles of the natural samples than the reinforced ones. The polypropylene fibers were prolonged at the predefined shear surface and increased the internal friction angle and shear resistance. The test results indicated that polypropylene fiber had a larger effect on the internal friction angle of coarse-grained (SC and SM-SC) alluvial soils. When the effect of PP fiber content on the internal friction angle of coarse-grained samples was examined, it was observed that 0.5% PP fiber additive caused a more significant increase than 1% PP fiber additive.

Separation of microalgae of various sizes and shapes is an important process that enables subsequent production of useful compounds. Herein, the separation of microalgae was accomplished using a magnetite-containing gel (42 μm) packed into a column. An algal suspension was injected into the top of the gel bed, after which water was passed through the column. The pressure generated during the process caused the lower domain of the gel bed to deform, resulting in narrowed gaps between the gel beads. When a suspension of Nannochloropsis sp. (0.0069-0.69 g L-1) was loaded and water was passed through the column at an applied pressure of 0.01-0.10 MPa, the majority of microalgae were captured within the upper domain of the gel bed, while only 20% were captured within the lower domain. The amount of Nannochloropsis sp. captured was expressed by an ordinary differential equation to determine the capture coefficient, K, and the maximum capture amount, Qmax. As pressure increased, gel gaps narrowed, K increased, and Qmax decreased because of a reduction in the number of effective capture sites upon compaction of the gel. When a mixed suspension of Anabaena sp., Monoraphidium sp., and Desmodesmus sp. (0.069 g L-1 each) was injected into the gel bed at an applied pressure of 0.01 MPa, only Anabaena sp. was captured at the bottom of the gel bed. This device can be applied for the separation of microalgae in rivers and the sea.

Cellulose nanofibrils (CNFs) have already been proved to be a potential candidate as one of the next-generation renewable and sustainable packaging materials. However, the mechanical and barrier properties of CNF films are not yet up to the mark for certain applications, especially at higher relative humidity. Those properties can be controlled by the degree of fibrillation of fibers and drying methods of films. Here we prepared CNF films from CNF suspensions with two different degrees of fibrillation- standard CNF (90% fine) and high-fine CNF (97% fine) by casting and filtration. These were dried in four different ways (air, oven, heat gun, and hot press drying) to better understand how these methods affect the physical, mechanical as well as oil, water vapor and oxygen barrier properties of the films. The CNF films made by hot press drying showed the highest tensile strength (98.82 MPa) and lowest water vapor permeability (13.91 g.mm/m2 day kPa). Hot press compaction on the dried films further improved the tensile strength by 13.1% and reduced the water vapor and oxygen permeability by 22.3% and 43%, respectively. The average value of oxygen permeability after hot press compaction was found to be 403.2 cc µm/m2 day atm, which can be considered as high oxygen barrier at 80% relative humidity. All prepared films showed maximum oil resistance value with kit number ‘12’, regardless of their preparation techniques. The result of folding a representative CNF film showed that the CNF film retained its oxygen barrier properties after a single line folding, but failed after two crossline folding.

This study aims to evaluate the effects of compaction on the anaerobic biodegradability of straw. In the study, compaction tests were carried out at different applied pressures, i.e., 0 (CK), 277 (T1), 555 (T2), and 1109 Pa (T3), respectively. The results showed that the maximum gain in biogas production was 298.35 mL·g−1 TS for the T2 reactor, significantly higher than CK (228.51 mL·g−1 TS) and T3 (249.14 mL·g−1 TS) reactors. The concentration of COD and TVFA of the T3 reactor was the highest throughout the anaerobic digestion (AD) process, the same thing for DHA, with maximum values of 39.12 g/L, 11.62 g/L, and 31.97 ug TPF/(h mL), respectively. However, the effect of compaction on the physical and chemical indicators of digestive fluid was not significant during the batch-type AD process. The factor analysis results suggested that the major factors affecting biogas production were influenced by the compaction and varied based on the different stages of digestion. Scanning electron microscopy (SEM) showed that the straw surface was damaged as the compaction increases. The degradation of TS in the AD did correlate to biogas yield, the best performance of TS loss rate was T2 (44.79%), and the lowest was CK (37.64%). This research concluded that compaction on gas production via changing the environment during the bath AD process and proper compaction could positively affect biogas yield, while excessive compaction will inhibit gas production. The impacts of compaction on the physicochemical indexes of the liquid digestate, structural and compositional changes of solid digestate, and biogas yield

Whether oil emplacement and diagenetic sequences provoke, deteriorate, or have no effect on pore network evolution, as implied by recent tests and theoretical analysis, are critical factors in forecasting hydrocarbon exploration and development potentials. Therefore, a systematic investigation on the effect of oil emplacement of tight sandstones is conducted to study the importance of this behavior on the pore evolution path. This study evaluated the role played by oil emplacement and diagenesis in the pore network evolution of Upper Triassic tight sandstones in the Ordos Basin. To help provide a comprehensive understanding, we have used a multidisciplinary method including physical properties, casting thin section, scanning electron microscope, X-ray diffraction, fluorometric, and inclusion analysis. The results demonstrate that the sandstones could be divided into four groups based on new criteria: calcareous sandstone, high soft component sandstone, low soft component sandstone with continual oil emplacement, and low soft component sandstone with intermittent oil emplacement. The physical properties of those types of sandstones were gradually reduced. Quartz cement captured hydrocarbon, carbonate captured hydrocarbon, free hydrocarbon, and adsorbed hydrocarbon were the four main kinds of hydrocarbons. The maturity of those sandstones was decreased progressively, indicating that the formation time of those hydrocarbons was favorable to maturity. Four stages of oil emplacement happened, and large-scale emplacement mainly occurred in the late Jurassic and early Craterous. The evidence demonstrated that tight sandstones’ high porosity could be attributed to positive diagenetic contributions with a complex interplay of chemical compaction, early formed clays, and large-scale oil emplacement. This work would provide new sights for a better understanding of the tight oil accumulation modes, and the findings could be applied in the hydrocarbon exploration and development field.

In this paper compressive behaviour of an Aluminium foam composite have been evaluated and discussed. The outcome reflects that quasi static stress –strain curve of Al composite was same as to Al foams. However, within the two strain ranges from strain less than 0.03 and strain greater than 0.2, the ideal absorption energy of the composites was higher than that of parent Al foams. When the strain ranged from 0.03 to 0.2 the ideal energy absorption efficiency value of the composite was lower than the Al foams. There are many methods for fabricating metal foams but we preferred powder metallurgy process. This process of production allows for the production of complex shaped foam parts. Many alloys including Aluminium, zinc, tin, lead and steel can be produced using this method. The fabricated part has a closed cell microstructure and a high fraction of porosity. Mechanical properties foams are evaluated including the axial crushing, Hardness and toughness test are also carried out. Applications are such as light weight construction and energy absorption for civilians as well as military uses.

The addition of cement for stabilization of expansive soils is one of the most commonly used methods. As with every calcium-based stabilizer, the time delay between the physical mixing of the stabilizer and compaction plays an important role in achieving the desired results after stabilization. However, a clear insight on the determination of optimum time delay for achieving the maximum desired compaction properties of cement-stabilized soils is yet to be established. Furthermore, the recent studies highlighted the use of sulfate to mitigate the negative effect of compaction time delay. The only drawback with the use of sulfate along with calcium-based stabilizers is the formation of ettringite, which deteriorates the stabilized soil matrix. In view of this, the present study is aimed at using the sulfate resistant cement (SRC) as a stabilizer along with the controlled addition of sulfate solutions to mitigate the negative effect of compaction time delay in stabilizing the expansive soil. To bring out the above effects, three periods of time delays (0 h, 6 h and 24 h) and three sulfate concentrations of 5000 parts per million (ppm), 10,000 ppm and 20,000 ppm were adopted. The experimental results showed that the delay in compaction resulted in the formation of clogs and reduction of strength of SRC-stabilized expansive soil. Upon sulfate addition to SRC-stabilized expansive soil, the formation clogs was not curtailed and resulted in the formation of ettringite clusters. These formations were captured with the help of scanning electron microscope (SEM) images and validated with electron dispersive X-ray spectroscopy (EDAX) analysis. Further, an attempt is also made to explain the mechanism of density and strength reduction with the aid of physico-chemical properties and mercury intrusion porosimetry (MIP) studies.

Nonpolar solvents have been reported to exhibit a nonlinear flux-pressure behavior in hydrophobic membranes. This study explored the flux-pressure relationship of six nonpolar solvents in a lab-cast hydrophobic poly(dimethylsiloxane) (PDMS) membrane and integrated the permeance behavior in the evaluation of the proposed transport model. The solvents exhibited a nonlinear relationship with the applied pressure, along with the point of permeance transition (1.5-2.5 MPa), identified as the critical pressure corresponding to membrane compaction. Two classical transport models, the pore-flow model and solution-diffusion model, were evaluated for the prediction of permeance. The solution-diffusion model indicated a high correlation with the experimental results before the point of transition (R2 = 0.97). After the point of transition, the compaction factor (due to membrane compaction after the critical pressure) derived from the permeance characteristics was included, which significantly improved the predictability of the solution-diffusion model (R2 = 0.91). A nonlinear flux-pressure behavior was also observed in hexane-oil miscella (a two-component system), confirming the existence of a similar phenomenon. The study revealed that a solution-diffusion model with appropriate inclusion of compaction factor could be used as a prediction tool for solvent permeance over a wide range of applied transmembrane pressures (0-4 MPa) in solvent-resistant nanofiltration (SRNF) membranes.

This study aims to determine the optimum process parameters for the fabrication of B4C-reinforced Al-Zn-Cu-Mg matrix composite by powder metallurgy route. Since casting could lead to problems in dispersion, pressure-assisted sintering was adopted for the fabrication of composites. The influence of various process parameters on the hardness and compressive strength were analyzed by using analysis of variance. Artificial neural network (ANN) and regression analysis were used to predict the hardness and compressive strength. ANN predicted better values than the regression analysis with mean squared error values of 0.27 and 4.72% for the hardness and compressive strength, respectively. Three cross-fold validation was used to check the accuracy of the model. Further, genetic algorithm was used to determine the optimum conditions for attaining maximum hardness and compression strength. The optimum conditions were a compaction pressure of 428 MPa, sintering temperature of 475 °C, sintering time of 75 min, and weight fraction of B4C 45%, giving compressive strength 552.06 MPa and hardness 186.12 HV. The validation experiments conducted on the optimal parameter setting, and the validation results were in good accord with the predicted results. Among all the samples, the 45% weight fraction of the B4C-reinforced sample was fractured during compression testing. Fractographic studies were performed using scanning electron microscopy, and cracking in B4C particles along with debonding in B4C-Al alloy interface was observed.

Compacted bentonite/sand mixtures are often considered as sealing/backfilling materials in deep geological disposal for radioactive waste. This study investigates the swelling pressure of compacted bentonite/sand mixtures with different bentonite fractions and dry densities upon hydration under constant-volume conditions. It was found that the swelling pressure of bentonite/sand mixtures is strongly dependent on their bentonite fraction and final montmorillonite dry density. For the samples with a bentonite fraction larger than a critical value, there is a linear relationship between the swelling pressure and final montmorillonite dry density. By contrast, for the samples with a bentonite fraction lower than the critical value, the sand particles will be skeletonized after strong compaction and lead to a heterogeneous distribution of montmorillonite, resulting in a larger swelling pressure compared to the samples with higher bentonite fractions. The maximum sand skeleton void ratio, corresponding to that at which the sand skeleton is just formed, is used to estimate the critical montmorillonite dry density and the critical bentonite fraction. Comparison between the test data and the estimated results shows good agreement, indicating the relevance of the identified swelling mechanism for compacted bentonite/sand mixtures.

The pore structure and movable fluid characteristics of tight conglomerate reservoirs are complex, which are greatly different from conventional reservoirs. The depositional mechanism is the fundamental factor controlling the physical properties of conglomerate reservoirs. However, there is a lack of systematic research on the pore structure and movable fluid characteristics of conglomerate reservoirs with typical sedimentary facies. This paper investigates the pore structure and movable fluid characteristics of conglomerate of different sedimentary facies based on various experiments. Casting thin sections, X-ray diffraction, scanning electron microscopy, high-pressure mercury injection, and nuclear magnetic resonance experiments were conducted on 32 conglomerates samples from the Mahu Sag, Junggar Basin, China. The quality classification method of tight conglomerate reservoirs is established. The results show that the conglomerate can be divided into three sedimentary facies; traction flow conglomerate (TFC) and pebbled sandstone (PSS) mainly develop intergranular pores and dissolved pores; and the pore diameter curves are mainly a double peak, single peak, and flat peak. Gravity flow conglomerate (GFC) mainly develops dissolved pores and interstitial micropores, and the pore diameter curve is mainly a single peak. PSS includes pebbled gritty sandstone (P(G)SS) and pebbled fine sandstone (P(F)SS). TFC and P(G)SS are favorable class I reservoirs, while GFC and P(F)SS are nonfavorable class II reservoirs. A new parameter, the ratio of the major axis to the minor axis of the pore outer ellipse (axial ratio), is proposed to quantitatively describe the compaction effect. The average axial ratios of the three lithofacies are 3.04, 3.98, and 8.78, respectively, indicating that the compaction is intensified and the pore structure becomes worse. By analyzing the correlation between pore structure parameters and permeability, it is found that the main controlling factors of permeability of GFC and TFC are sorting and connectivity, respectively, and the main flow radius is the most suitable parameter to describe permeability. A linear spectral decomposition method was used to establish a new quantitative calculation method of movable fluid saturation for different types of pores, and the results show that the movable fluid saturation of intergranular pores is the highest (average: 65.43%), and the movable fluid saturation of TFC and P(G)SS with more intergranular pores is the highest. Movable fluid saturation is inversely proportional to the content of I/S and the compaction rate and positively proportional to the content of quartz and feldspar and the cementation rate. The fluid mobility of water-wet samples is weaker. The research results provide theoretical support for the identification of favorable reservoirs and the cognition of a development mechanism.

Titanium is widely used in the fields of medicine, industry, and biological science due to its excellent properties. In addition, titanium powder metallurgy (PM) is widely used in production becaus...

The Abu Gabra and Bentiu formations are widely distributed within the interior Muglad Basin. Recently, much attention has been paid to study, evaluate and characterize the Abu Gabra Formation as a proven reservoir in Muglad Basin. However, few studies have been documented on the Bentiu Formation which is the main oil/gas reservoir within the basin. Therefore, 33 core samples of the Great Moga and Keyi oilfields (NE Muglad Basin) were selected to characterize the Bentiu Formation reservoir using sedimentological and petrophysical analyses. The aim of the study is to de-risk exploration activities and improve success rate. Compositional and textural analyses revealed two main facies groups: coarse to-medium grained sandstone (braided channel deposits) and fine grained sandstone (floodplain and crevasse splay channel deposits). The coarse to-medium grained sandstone has porosity and permeability values within the range of 19.6% to 32.0% and 1825.6 mD to 8358.0 mD respectively. On the other hand, the fine grained clay-rich facies displays poor reservoir quality as indicated by porosity and permeability ranging from 1.0 to 6.0% and 2.5 to 10.0 mD respectively. A number of varied processes were identified controlling the reservoir quality of the studies samples. Porosity and permeability were enhanced by the dissolution of feldspars and micas, while presence of detrital clays, kaolinite precipitation, iron oxides precipitation, siderite, quartz overgrowths and pyrite cement played negative role on the reservoir quality. Intensity of the observed quartz overgrowth increases with burial depth. At great depths, a variability in grain contact types are recorded suggesting conditions of moderate to-high compactions. Furthermore, scanning electron microscopy revealed presence of micropores which have the tendency of affecting the fluid flow properties in the Bentiu Formation sandstone. These evidences indicate that the Bentiu Formation petroleum reservoir quality is primarily inhibited by grain size, total clay content, compaction and cementation. Thus, special attention should be paid to these inhibiting factors to reduce risk in petroleum exploration within the area.

[Petroleum system modelling showing present‐day maturity (%Ro) of the Vaca Muerta Formation from from the Agrio Fold and Thrust Belt (west) to the NE Platform (east). The increase in TOC0 values from east to west is associated with thickening of the unit, which suggests the potential larger volumes of generated hydrocarbons for the same thermal gradient. The E–W thermal maturity trend is consistent with the decrease in HI and increase in TR values to the west, indicating that in conjunction with increased TOC0, organic pores represent the main control on total porosity in organic‐rich intervals of the unit. , Abstract The Vaca Muerta Formation (Tithonian–early Valanginian) is the main source rock in the Neuquen Basin and the most important unconventional shale resource in South America. In the present study, organic geochemistry, electron microscopy and basin and petroleum system modelling (BPSM) were combined to evaluate source rock properties and related processes along a transect from the early oil (east) to the dry gas (west) window. The unit is characterized by high present‐day (1%–8% average) and original (2%–16% average) total organic carbon contents, which increase towards the base of the unit and basinal (west) settings. Scanning electron microscopy shows that organic pores derived from the transformation of type II kerogen. Isolated bubble pores are typical of the oil window, whereas bubble and densely distributed spongy pores occur in the gas stage, indicating that the maturity gradient exerts strong control on organic porosity. Organic geochemistry, pressure and porosity data were incorporated into a 2D basin petroleum system model that includes the sequential restoration of tectonic events and calculation of compaction trends, kerogen transformation, hydrocarbon generation and estimation of pore pressure through geologic time. The W–E regional model extends from the Agrio Fold and Thrust Belts to the basin border and allows us to evaluate the relationship between thermal maturity and timing of hydrocarbon generation from highly deformed (west) to undeformed (east) regions. Modelling results show a clear decrease in maturity and organic matter (OM) transformation towards the eastern basin margin. Maximum hydrocarbon generation occurred in the inner sectors of the belt, at ca. 120 Ma; long before the first Andean compression phase, which started during the Late Cretaceous (ca. 70 Ma). Miocene compression (15–7 Ma) promoted tectonic uplift of the inner and outer sectors of the belt associated with a reduction in thermal stress and kerogen cracking, as well as massive loss of retained fluids and a decrease in pore pressure. The OM transformation impacted (a) the magnitude of effective porosity associated with organic porosity development, and (b) the magnitude and distribution of pore pressure within the unit controlled by hydrocarbon generation and compaction disequilibrium. BPSM shows a progressive increase in effective porosity from the top to the base and towards the west region related to the original organic carbon content and maturity increasing along the same trend. Overpressure intervals with high organic carbon contents are the most prone to develop organic pores. The latter represent favourable sites for the storage of hydrocarbons in the Vaca Muerta Formation.]

The paper describes the optimization of the hot compaction process to simultaneously increase hardness and decrease the wear coefficient of zirconium silicate reinforced BMCs. L9 orthogonal array is chosen for setup the experiment. Examining the influencing parameters is carried out on factors such as pressure, temperature, particle size, and particle content. Grey relation analysis is used to investigate to produce an optimal combination of parameter levels. The transmission electron scanning is used to study the morphology of zirconium silicate. The wear coefficient of the specimen was investigated by using the weight loss method. A scanning electron microscope was carried out to evaluate the wear track surface of the composite. The test results show that the particle size is the most influential hot compaction parameter. The optimal conditions for the hot compacting process are the temperature level at 350 °C, the pressure level at the 400 MPa level, the particle content level at 12 % weight, and the particle size level at 80 µm. In this optimal condition, the prediction GR-Grade value is 0.695. The validation test results showed that the GR-Grade value increased by 0.15, the hardness increased by 25%, and the wear coefficient decreased by 53%. This optimization method with Gray Relational Analysis has proven to be effective in the hot compaction process for improving the tribology behavior of the composites.

To further improve the volumetric energy density of LiFePO4 based cathode materials, herein, lithium iron phosphate supported on carbon (LiFePO4/C) with high compaction density of 2.73g/cm3 has been successfully synthesized by elaborate controlling the particle size of precursor slurry and the resultant LiFePO4/C composite. The as-synthesized composite is demonstrated to be an attractive positive electrode candidate for lithium-ion batteries, and the capacity of 18650 cell with LiFePO4/C as cathode reaches 7.0 Wh. Furthermore, high-/low-temperature discharge performance and reversibility of capacity retention are excellent. XRD patterns show that LiFePO4/C with higher compaction density exhibited better crystallinity corresponding to olivine structure. Electrochemical impedance spectroscopy (EIS) tests demonstrate that high compaction density of the cathode materials is beneficial for electrochemical property promotion. The as-synthesized LiFePO4/C is a promising candidate for the development of high-performance, cost-effective lithium-ion batteries for electric vehicles, and this work provides a feasible way to synthesize LiFePO4/C composite with high compaction density and excellent electrochemical performance.

Porous Si100-xSnx samples with x = 15, 30 and 40 at.% were produced from Si and Sn elemental powders by mechanical alloying followed by two different compaction and sintering processes: cold uniaxi...

The quality of carbon anodes plays an essential role in the production of primary aluminum. The vibro-compaction is one of the most important steps of the anode fabrication process, which affects the anode quality. Over and under-compacting results in anodes with high electrical resistivity, poor mechanical and physical properties. Therefore, the compaction conditions should be chosen carefully. A method and a sound analysis software were developed to determine the optimum vibration time using the sound generated by the vibro-compactor during anode compaction. This method was tested with a bench-scale system both in the laboratory and in the plant. It is simple, fast and inexpensive. The effect of anode raw materials (types of coke and pitch) and top-former bellow pressure of the vibro-compactor on the optimum compaction time as well as the effect of compaction time on anode properties were investigated. The results showed that there are three stages of anode formation during vibro-compaction, good quality anodes can be produced by using compaction time around the optimal value, and the utilization of sound analysis reduces the compaction time.

In this study, the pore characteristics and the factors of maximum methane adsorption capacity (MAC) of mudstone in the early diagenetic stage (EDS) and the contribution rate of clay mineral (CM) adsorption were analyzed. In addition, the adsorption coupling effect of CM and organic matter (OM) was discussed. Studies have shown that pores of coal measure mudstone in the early diagenesis stage are mainly small pores with slanted platelike staggered and overlapped pores, with more pore opening directions. The main controlling factors of the maximum MAC of mudstone are OM and CM, and the direct expression is the pore surface area. In the EDS, the contribution rate of CM in mudstone is lower, while the contribution rate of OM to the MAC of mudstone is higher. There is an adsorption coupling effect of CM composition and OM. OM in mudstone is scattered, and the CMs have a supporting effect, which leads to OM in mudstone having a large contact area with the open space and has many effective pores. OM in coal is concentrated, and the surface area of OM per unit volume is small (compared with OM in mudstone). The compaction and deformation characteristics of CMs have a plugging/sealing effect on the pores of OM in the coal, which makes the effective pores of OM per unit volume in coal lower than those in mudstone.

Background: Tablets must be able to release the active drug in the gastrointestinal tract for absorption. The release profile of solid pharmaceutical dosage formulations can be quantified by assessing the disintegration and dissolution times tests. Binders are adhesives either from sugar or polymeric material that are added to tablet formulations to provide the cohesiveness required for the bonding together of the granules under compaction to form tablets.Objective: The objective of the study was to formulate and assess ibuprofen tablets using different concentrations of binders (Acacia and Gelatin).Methods: The granules were prepared using wet granulation method and analysed for flow properties based on USP/NF protocols. After granule compression, the tablets release profiles were thereafter assessed via the tablet dissolution and disintegration tests.Results: Weight variation, thickness and diameter were within the acceptable values for all batches indicative of a uniform flow. Batches with binder concentrations of 10 % and 20 % failed disintegration test due to a disintegration time above 15 min while the release rate for batches 1 and 4 was about 88 % in 60 min as against the other batches whose release rate was less than 50 % in 60 min as a result of increasing their binder concentrations.Conclusion: The study concluded that increasing the concentration of acacia and gelatin above 5% led to a decrease in percentage of drug released and an increase in disintegration time above 30 mins because 5% batches gave the best release profiles.

Fluid inclusion analysis and testing were conducted to clarify the relationship between reservoir densification and hydrocarbon accumulation in the Paleogene Pinghu and Huagang formations in the Xihu Depression. The hydrocarbon accumulation stages of the reservoirs were studied in combination with the reconstruction results of burial and thermal evolution histories. Furthermore, the relationship between reservoir densification and accumulation charging was clarified in combination with the pore evolutionary history. In accordance with the time relation between reservoir densification and hydrocarbon charging, the reservoirs were classified into three types: pre-charging, syn-charging, and after-charging densification. Results indicated that large-scale hydrocarbon charging occurred in 11–0Myr. Reservoir densification was mainly caused by strong mechanical compaction and pore filling by well-developed siliceous and carbonate cements. Entering the middle diagenetic stage A1, the reservoir was under an acidic-diagenetic environment, resulting in the development of secondary dissolution pores. If large-scale hydrocarbon charging occurred during this period, then an after-charging densification reservoir, which is the most suitable type for hydrocarbon accumulation, might have developed. Entering the middle diagenetic stage A2, the reservoir was under an acidic-alkaline transitional diagenetic environment. During this stage, dissolution became weak, and compaction and cementation were enhanced, resulting in the continuous loss of pore space and reservoir densification. Entering the middle diagenetic period B, the reservoir was under an alkaline-diagenetic environment, and the reservoir had been largely densified. If large-scale hydrocarbon charging occurred during this period, a pre-charging densified reservoir, which is the worst reservoir type for hydrocarbon accumulation, might have developed.

The tribological performance of compacted and noncompacted polydopamine (PDA)+polytetrafluoroethylene (PTFE) nanocomposite coatings on stainless steel (SS) substrates was investigated. The compacti...

Poly (ethylene oxide) (PEO) has been widely used in abuse-deterrent formulations (ADFs) to increase tablet hardness. Previous studies have shown that formulation variables such as processing conditions and particle size of PEO can affect ADF performance in drug extraction efficiency. This work aims to understand the effect of PEO grades and sources on the compaction characteristics of model ADFs. PEOs from Dow Chemical and Sumitomo Chemical with different molecular weights were examined using a Styl'One compaction simulator at slow, medium, and fast tableting speeds. Particle-size distribution, thermal behavior, tabletability, compressibility using the Heckel model, compactibility, and elastic recovery were determined and compared between the neat PEOs and model ADFs. Multivariate linear regression was performed to understand the effect of compression conditions and PEO grades and sources. Our results show that neat PEOs with high molecular weight exhibit high tabletability. The source of neat PEOs contributes to the difference in tabletability, out-die compressibility, compactibility, and elastic recovery. However, the influence of the PEO source on tabletability and compactibility decreases after adding the model drug. In our model ADFs, tablets using PEOs with high molecular weight have high crushing strength, and tablets using PEOs from Dow Chemical display low elastic recovery.

Exploring the tightness mechanism through a quantitative analysis of the pore evolution process is the research hotspot of tight oil reservoirs. The physical characteristics of Chang 6 (Ch-6) sandstones in the western Jiyuan area have the typical features of a tight oil reservoir. Based on the reservoir physical property, lithological characteristics, diagenetic types and sequence, and burial and thermal evolution history, this study analyzes the factors leading to reservoir tightness and establishes the model of the pore evolution process. The results show that the sedimentary microfacies type controls the reservoir detrital material and further affects its physical properties. The high content of feldspar and rock fragments and the fine grain size are the material cause for the reservoir tightness. The sandstones of the main underwater distributary channel are the dominant sedimentary bodies for the development of a high-quality reservoir. In terms of diagenesis, compaction is the primary cause for reservoir tightness, and the porosity reduction by cementation is weaker than that by compaction. Meanwhile, the quantitative calculation results indicate that the porosity losses by compaction, carbonate cementation, kaolinite cementation, chlorite coatings, and siliceous cementation are 23.5, 3.1, 3.8, 3.0, and 0.8%, respectively. In addition, dissolution is significant to improve the reservoir physical property, and the increase of dissolved porosity is around 3.2%. More significantly, this study uses a detailed and systematic method for analyzing the tightness mechanism and the pore evolution process of the Ch-6 sandstones in the western Jiyuan area, Ordos Basin, China.

In the present study, the aluminium hybrid composites (AHCs) are developed by the powder metallurgy method. Pure aluminium is reinforced with varying weight percentages of ceramic reinforcements (S...

The acquisition of geological data is of fundamental importance for the study of areas potentially relevant to the occurrence of petroleum systems. In this context, the development of research in outcropping rock formations has proven to be a potential method to investigate the geology of the geological unit studied in subsurface. One of several examples found in Brazil are the outcrops Barreiras do Boqueirão and Praia de Japaratinga, belonging to the Maceió Formation, located in the northern coast of Alagoas State. The Maceió Formation has the lowest cretaceous sedimentation record within the Alagoas Basin. This sedimentation, present almost in the entire basin, is located mainly in its subsurface. This geological unit is composed of several lithologies, including a turbiditic sequence predominantly formed by shales, sandstones and conglomerates. This environment makes it possible the occurrence of a petroleum system. Our research group chose to investigate this environment because turbiditic sandstones are excellent petroleum reservoirs, and they have a great economic relevance in the Brazilian petroleum scenario. To develop this research, a petrographic characterization of the Maceió Formation sandstones was conducted to help determine the compositional and diagenetic aspects of these rocks and infer the influence of diagenetic processes on the quality of these sandstones as reservoirs. The petrographic analysis showed that the studied sandstones can be classified as arkose and quartzenite, present moderate porosity and good permeability, observed through the predominant presence of floating contacts between the grains. The porosity is predominantly primary intergranular, averaging 15%, but secondary porosity by fracture and dissolution of primary grains also occurs. The sandstones of the Maceió Formation are poorly and moderately selected, with angular, sub-angular and sub-rounded grains, showing low to medium textural maturity, which may also influence the quality of the reservoir, impairing the primary porosity in the samples. The three diagenetic stages were identified as: eodiagenesis, mesodiagenesis, and telodiagenesis. The diagenetic processes found were: mechanical compaction, beginning of chemical compaction, clay infiltration, pyrite cementation, grain dissolution, chlorite cementation, quartz sintaxial growth, and mineral alteration and replacement. Mineral replacement was a phenomenon observed quite expressively in the samples analyzed. This event was evidenced, particularly, by the substitution of muscovite and feldspar for kaolinite, the alteration of biotite was also identified in the samples. Therefore, one can infer that the diagenetic processes had little influence on the reduction of the original porosity in the samples studied. In general, considering all the analyses performed in this research, one can see that the sandstones of the Maceió Formation (northern portion) present a good reservoir quality.

The concept of form stability is considered. A semifinished product in the form of a ring from a thermoplastic mass based on SiC powder has been made on the installation for injection molding developed at the Bakul Institute for Superhard Materials of the National Academy of Sciences of Ukraine in accordance with the established technological parameters optimized by the results of computer modeling. Schemes of loading and dividing the ring into samples in the form of prismatic segments are presented. A technique for the preparation of experimental samples is proposed. The study of the compressive strength of the samples from the injected semi-finished product has been carried out on the FP-5 mechanical test machine and a corresponding здще of its change has been constructed. The formation of a barrel shape during compression tests of samples, both along the radial and tangential directions, has been established. The values of the minimum and maximum loads at which the samples are destroyed have been determined. An increase in the compaction of the thermoplastic mass around the injection point has been experimentally proved. The scheme and the actual image of crack distribution as a result of destruction of samples have been presented. It is shown that the failure occurs in the area of the presence of the calculated parting lines, which have become stress concentrators.

Carbide lime is a by-product obtained during the manufacturing of acetylene from the reaction of calcium carbide and water. A major portion of carbide lime is dumped in waste deposition areas, creating an environmental problem. Carbide lime and fly ash have possible applications in slope stabilization, subgrade improvement of roads, and soil treatments under shallow foundations. A series of Atterberg limits tests, compaction tests, unconfined compressive strength tests, ultrasonic pulse velocity tests, and wetting-drying tests were performed on carbide lime and fly ash treated clay soils to evaluate the effects of additive content, curing time, strength development, and the effects of wetting and drying. A total of 8% of carbide lime constituted the fixation point, and peak strength was achieved at 12% carbide lime content. A total amount of 25% additive was found as a threshold changing the Atterberg limits. Test results indicated that the strength of the treated soil improved by the existence of carbide lime and fly ash; best performance was observed in 28-day specimens with 10% carbide lime and 20% fly ash content reaching to 8 times larger strength than untreated soil. The failure patterns of the specimens reflected the curing time and wetting-drying effects. Although, the application of wetting-drying cycles deteriorated the treated soil, the presence of carbide lime partially prevented the strength loss. New relationships between normalized strength and curing time depending on carbide lime content were proposed. Furthermore, a linear relationship between the unconfined compressive strength and the ultrasonic pulse velocity of the treated soils was established., Ege UniversityScientific Research Projects Center, Turkey [17 MUH 032], A part of this research was funded by Ege UniversityScientific Research Projects Center, Turkey, with Grant No: 17 MUH 032.