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One of the primary objectives of deep space exploration is the successful retrieval of soil samples from extraterrestrial objects. The unique sealing requirements for surface soil samples from extraterrestrial bodies present a significant challenge when designing sample containment systems. In this work, a Shape Memory Alloy-based Knife-edge Seal System (SMAKSS) is investigated to enhance the sealing performance of containers used for extraterrestrial soil samples. This research employs a combined approach of theoretical analysis and experimental tests to validate the correlation between the heating temperature of the Shape Memory Alloy (SMA) and the resulting sealing leakage rate. Furthermore, the study examines the leakage rate trends and knife-edge penetration depths of SMAKSS systems constructed with three different material sets under increasing heating temperatures, as well as a comparison of leakage rates between heating temperature and room temperature conditions. Among the three material sets examined, the results indicate that the SMAKSS system with a TA15 titanium alloy lid and a 1070 aluminum alloy container demonstrates a lower leakage rate of 6.97 × 10−11 Pa·m³/s at heating temperatures and superior sealing efficacy even at room temperature. Consequently, the SMAKSS demonstrates a lower leakage rate and superior environmental temperature adaptability, making it the most suitable choice for extraterrestrial soil sample return missions. • The investigated shape memory alloy-based knife-edge seal system is investigated to enhance the sealing performance and biological sterilization of containers used for extraterrestrial soil samples. • This method tackles a common issue in conventional sealing technologies, where leakage rates increase rapidly during rapid temperature drops. • The TA15-1070 SMAKSS exhibits the lowest leakage rate of 3.53 × 10−11 Pa m3/s at 150 °C, and this rate decreases to 1.95 × 10−11 Pa m3/s as the temperature drops to room temperature. • The leakage rateof this structural is consistent with those observed in the lunar sample encapsulation used in China's Chang'e 5 mission and the sample storage tubes in the Mars 2020 mission. [ABSTRACT FROM AUTHOR]

• Effects of outdoor exposure on the CFRP-concrete bond behaviors were investigated. • The outdoor exposure in the frigid zone deteriorated the CFRP-concrete bonds. • An environmental reduction factor for CFRP-concrete bond in frigid zone was proposed. The bond strength between a carbon-fiber-reinforced polymer (CFRP) plate or sheet and concrete is susceptible to harsh field environments and plays a key role in the strengthening function of CFRP in the externally bonded strengthening technology. In the present study, the influence of outdoor exposure in northeast China, a frigid zone, on the bond behavior between pultruded CFRP plate and concrete block was investigated using a single-lap shear test. The test results indicated that the exposure caused a change in the cohesive failure of concrete to debonding between the concrete and adhesive, similar to water immersion. The fracture energy, maximum shear bond stress and load capacity of the CFRP-concrete bond joint decreased with the exposure time. An environmental reduction factor was proposed to account for the degradation of the CFRP–concrete bond for the investigated exposure. [ABSTRACT FROM AUTHOR]

The aim of this study is to analyze relationships between lithological heterogeneity and petrophysical properties in fluvial features of the Guantao Formation (Miocene) in view of reservoir water flooding in the Shengli oilfield (Shandong Province, RPC). Black oil simulation models of intermediate scale elements such as point bars and their lateral accretion beds. Using analysis assay data from sealed coring wells demonstrates permeability, rather than porosity, as the determining constraining parameter. The Guantao formation consists of fluvial deposits of braided and meandering river. In the Shengli Oil Field, the target layer of Ng5 2+3 is mainly composed of well-sorted fine-grain sandstone, and it mainly develops in-channel point bars which are characterized by lateral accretion with graded sand-shale beds showing notable variations in porosity and permeability. Dense well spacing sections were used to identify geometric architectural parameters of the subsurface sandstone interpreted as fluvial point bars. These parameters were used to build the model of the point-bar stratigraphic framework, accurately reflecting the Guantao Formation channel-fill architecture. An exponential function was used to reconstruct the permeability model of intermediate-scale elements and lateral-accretion beds in contrast with models constrained by porosity and shale drapes. Analysis assay data of sealed coring wells indicate that porosity does not display obvious changes in the main body part of point-bar sandstone, and porosity has less obvious correlations with permeability and grain size. The grain size of sandstone exhibits regular variation in intermediate-scale depositional elements and lateral-accretion beds. Vertically, the change of permeability presents exponential functions in the same intermediate-scale element and lateral-accretion bed. Two- and three-dimensional (2-D and 3-D) models and black-oil simulations compare scenarios based on different lithologies, shale drapes, observed grain-size trends, petrophysical properties, and modeling methods. Affected by the shape features of lateral-accretion interfaces, the enrichment areas of remaining oil obviously exhibit morphological characteristics of the echelon. There is little difference in breakthrough time between the “shale drapes” model using porosity as constraint and that using the permeability-distribution function as constraint, but the recovery percentage of the latter model is obviously lower than that of the former. The model in which lateral-accretion beds and units were modeled with the permeability-distribution function as the constraint is about 6% lower than the “shale drapes” model constrained by porosity in recovery percent after 10 years. From the development effect, the injection-production method in which the water-flooding direction is along the dip direction of lateral-accretion surfaces is a little better than that in which the water-flooding direction is opposite to the dip direction of intersurfaces. [ABSTRACT FROM AUTHOR]

Fluid transport properties of fault rocks are crucial parameters that affect earthquake nucleation and rupture propagation. In this study, we examined the internal structure, mineral composition and fluid transport properties of fault rocks collected from two shallow boreholes penetrating a granitic rupture zone on the Yingxiu-Beichuan Fault (YBF) that was activated during the 2008 Wenchuan earthquake. Fluid transport properties were measured using water as pore fluid at effective pressures ( P e ) ranging from 10 MPa to 165 MPa. Permeabilities of fault rocks exhibit a wide variation from 2.1 × 10 − 22 m 2 to 4.6 × 10 − 17 m 2 , strongly depending on rock types and overburden pressure. Specifically, at P e of 165 MPa, the damage zone samples have permeabilities from 5.0 × 10 − 21 m 2 to 1.2 × 10 − 17 m 2 , and the fault gouges are between 2.1 × 10 − 22 m 2 and 3.1 × 10 − 19 m 2 . Thus, the YBF consists of a low-permeability fault core acting as fluid barrier, and surrounding high-permeability damage zones acting as fluid conduits. Combining the structural and compositional results and transport data together, we propose that the interplay between cataclasis and fluid-rock interactions controls the hydraulic properties and their response to the fault zone evolution. It is noteworthy that we measured extremely low permeabilities but high porosities and high specific storages for the gouges. The cemented cataclasites, which are inferred to be equivalent to the rocks in which the Wenchuan earthquake nucleated also have low permeabilities, suggesting the fault zone is a potential area for fluid storage and capable of generating high pore pressure at depths. According to our laboratory data, we found fluid pressurization could occur at depths below 2.7 km. We suggest thermal pressurization has played an important role in causing the dynamic weakening of the Wenchuan earthquake. [ABSTRACT FROM AUTHOR]

The Yitong Basin is a strike-slip fault basin, which tectonically belongs to the northern section of the Tanlu Fault Zone. Exploration has demonstrated that the northwest Yitong Basin is a hydrocarbon enrichment zone. However, the complex geological conditions and a poor understanding of the accumulation models and hydrocarbon enrichment factors have impeded petroleum exploration in the basin. This paper focuses on the hydrocarbon accumulation processes in the strike-slip fault zone in the northwest Yitong Basin. We proposed the reservoir critical porosity concept for reservoir dynamic evaluation. A mathematical model for sandstone porosity evolution in the northwest Chaluhe Fault Depression is established to reconstruct the sandstone porosity over geological time. A fault critical burial depth is proposed to evaluate the present fault-sealing property. The critical condition for oil charge into sandstone was also simulated using an oil-charge simulation experiment. The results indicate that the reservoir critical porosity of the Shuangyang Formation in the northwest Chaluhe Fault Depression was 11% during the accumulation. The present tight sandstone reservoirs in the northwest Yitong Basin were conventional reservoirs during the hydrocarbon accumulation with relatively high porosity and permeability, beneficial for hydrocarbon accumulation at the time. The critical burial depth of faults in the middle–deep layers is 2050 m in the northwest Chaluhe Fault Depression. The hydrocarbons can be effectively sealed when the burial depth of the fault is greater than the critical burial depth. The critical hydrocarbon accumulation threshold for a sandstone reservoir depends on the coupling of reservoir critical porosity and critical injection pressure during hydrocarbon accumulation. We put forward three hydrocarbon accumulation plays for the northwest Chaluhe Fault Depression: (1) extensional fault block play, which is close to the source rock and experienced two stages of hydrocarbon accumulations; (2) flower structure play, which is far away from the source rock and is characterised by a late hydrocarbon charge and accumulation; and (3) fault-lithological play, which is far away from the source rock and experienced a late hydrocarbon accumulation. For the Yitong Basin, reservoir properties and faulting appear to be the main controlling factors for hydrocarbon accumulations. [ABSTRACT FROM PUBLISHER]

Abstract: Late Quaternary shallow-biogenic gas reservoirs are well-developed in the Qiantang River incised valley, eastern China. They present as sand bodies in the floodplain–estuary facies. Silty clay beds of floodplain–estuary facies and mud beds of estuarine–shallow marine facies serve as the direct and indirect cap beds, respectively, and the former has much better sealing ability. Capillary pressure sealing, pore water pressure sealing, and hydrocarbon concentration sealing contribute to the conservation of shallow-biogenic gas in the reservoirs, in which the pore water pressure sealing may be the most important factor. Here the capillary pressure sealing mechanism is clarified by an indirect method, i.e., the difference of permeability between the cap beds and reservoirs, as the displacement pressure of late Quaternary sediments which is unconsolidated is difficult to be tested. The cap beds have higher capillary pressure than the reservoirs for the far lower permeability. Pore water pressure of cap beds exceeds the total of pore water pressure and original gas pressure of underlying reservoirs. Disequilibrium compaction, swelling of clay minerals and gas generation are responsible for the generation of high pore water pressure. In addition, the hydrocarbon content of the cap beds is higher than that of the reservoirs which could restrain the flow up of gas in the reservoirs. [Copyright &y& Elsevier]

Abstract: This paper discusses migration styles and primary controls of petroleum migration pathways in heterogeneous carrier beds in the Damintun Depression, Bohai Bay Basin. There are two types of crude oils in the Damintun Depression: a high wax oil (wax hydrocarbon content between 8 and 60%) and a normal oil (wax hydrocarbon content lower than 8%). The high wax oil and normal oil are distinctly different both in biomarker compositions and in distribution patterns of carbon isotopic ratios for individual alkanes, and were confirmed to have been generated from different source rocks. Modeling of secondary migration pathways of both the high wax oil and the normal oil was conducted using a simple three-dimensional model, which assumes that the positions of petroleum migration pathways are controlled by the morphology of the sealing surfaces without taking into consideration the influence of permeability heterogeneity (the morphology-controlled migration model). The modeling results have reasonably well predicted the occurrences of both the high wax oil and the normal oil. All commercial petroleum accumulations are along the predicted preferential petroleum migration pathways (PPMP) formed by focusing of numerous “small petroleum streams” close to the kitchens. The focusing of oils originating from a large area of the generative kitchens is essential for the formation of large oilfields. The strong porosity and permeability heterogeneities of the carrier beds, and the relatively high prediction accuracy of the modeling, suggest that the preferential petroleum migration pathways, although influenced by permeability contrast at local scales, can be effectively predicted at a basin or depression scale under certain circumstances using a model that does not take into consideration the effect of heterogeneity. Most dry holes are not on the predicted petroleum migration pathways, suggesting that the three-dimensional migration pathway modeling may provide a useful tool to reduce exploration risk. [Copyright &y& Elsevier]

The experimental data yielded by Rock-Eval pyrolysis, kerogen atomic H/C, Py-GC and gold-tube sealing thermal simulation on the marine Cambrian-Ordovician source rock from the Tarim Basin revealed that the upper limit of maturity for natural gas generation or the "deadline of gas generation" for marine types I and II kerogens is equal to 3.0% of vitrinite reflectance (Ro); while the "deadline of gas generation" for type III kerogens typically like coals is as high as 10% Ro. Thus, different organic matter has obviously different utmost maturities for gas generation. The mass-balance calculation by kerogen elements showed that when Ro>1.5%, the utmost amount of gas generation for the marine type II kerogen is less than 185 m³/t TOC, accounting for less than 30% of its total hydrocarbon generative potential; when Ro>2.0%, it becomes 110 m³/t TOC, less than 20% of the total hydrocarbon generative potential. The amount of the gas generative potential obtained by Rock-Eval is only around one tenth of the calculated value by the mass balance of kerogen elements at the same thermal evolutionary stage, while those by Py-GC and gold-tube sealing simulation are intervenient between the above two. The utmost of gas generative potential at the over 1.3% Ro stage is around 60-90 m³/t TOC, therefore, the amount of gas generation obtained by Rock-Eval is the minimum of gas generative potential, while that by the mass-balance calculation of kerogen elements is the maximum that the actual amount of gas generation should not exceed. [ABSTRACT FROM AUTHOR]

• In the W/Steel bonding, the effects of interlayer and intermetallics on the joints failure have been discussed. Compared the reaction products, shear strength and failure mode, the copper has been chosen as the interlayer material. • It is considered that the condition of 1000 °C, 20 MPa is rather proper to bond steel/steel interface to control the deformation of cooling channel. • Using HIP technology, we have prepared a 600 mm-long W(Cu)/steel FW straight plate. Dimension tests shown that the channel sizes were within 8 ± 0.5 mm, which has met the technical requirement. • Finally, we presented some electron-beam welding results for the assembling of sub-components. As one candidate of blankets for China Fusion Engineering Test Reactor (CFETR), the Water Cooled Ceramic Breeder (WCCB) blanket is proposed and designed in Institute of Plasma Physics, Chinese Academy of Sciences (ASIPP). Supported by the National Key R&D Program of China, we formulated a roadmap on its manufacturing. In this work, the research and development (R&D) on bonding technology for W/Steel and Steel/Steel has been summarized first. Bonding quality was evaluated by microstructure observation and mechanical test. In the W/Steel bonding, the effects of interlayer and intermetallics on the joints failure have been discussed. In the Steel/Steel bonding, the deformation issue and the heat treatment of RAFM Steel have been presented. Then the progress on manufacturing technology and bonding quality tests of the middle-size first wall (FW) mockups also have been shown in the paper. Finally, some technology experiments of assembling weld for the sub-components have been discussed. It is considered that this research construct a foundation to manufacture the WCCB component. [ABSTRACT FROM AUTHOR]