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Analytical solutions for geosynthetic reinforced fills over a void have appeared in the literature starting in the 1980s. Current solutions pay little or no attention to the influence of the creep-reduced stiffness of the geosynthetic reinforcement under tensile loading. This paper addresses this gap by introducing a reinforcement stiffness limit state in the design of these systems. The choice of reinforcement stiffness is based on a simple two-parameter hyperbolic isochronous load–strain model developed by the authors and applied to a large database of uniaxial and biaxial geogrids and woven geotextiles. The paper provides a design chart procedure that can be used with four well-known analytical solutions to compute the maximum reinforcement load. In addition to the stiffness limit state, the design chart approach includes vertical deformation and reinforcement strain serviceability limit states, and a tensile strength limit state. A novel feature of the design charts is a quantitative link to the ultimate strength of the reinforcement to estimate the isochronous stiffness of the reinforcement for different elapsed loading times and strains. There are many instances in the literature where the reinforcement stiffness was taken from a constant rate-of-strain tensile test. The paper shows that this is non-conservative for design.

Metallic nanolaminated materials possess excellent mechanical properties due to their unique modulation structures and interfacial properties. However, how microdefects affect their mechanical properties is still uncertain. To evaluate the influences of void location (in the crystalline layer and the Ti/Ni interface), void diameter (d) and thickness of the intermediate layer (h) on overall tensile behaviors, various types of defective Ti/Ni nanolaminates with pre-existing void are established by the molecular dynamics method in this work. The results indicate that the strength and plastic deformation mechanisms are strongly dependent on those determinants. Yield stresses of Ti/Ni nanolaminates decrease distinctly with increasing void diameter, while peak stresses with a void in the crystalline layer decrease with increasing d/h. Different void locations lead eventually to disparate initial plastic deformation carriers around the void, and various evolutions in the microstructure of the defective Ti/Ni nanolaminates. The Ti/Ni interface plays a significant role in the tensile process. The semi-coherent interface impedes new grains and lattice dislocations from passing across the interface, while the incoherent interface facilitates dislocations generating and sliding along the interface, and absorbs the dislocations moving to the interface. The results also indicate that the strain rate significantly affects the evolution of the microstructure and the tensile properties of defective Ti/Ni nanolaminates.

Metal-organic frameworks (MOFs) derivatives have been widely explored as highly efficient electromagnetic absorbing materials. Due to their diverse coordination arrangements, morphologies, and unique structures, MOFs provide promising avenues for synthesizing materials with customized properties. However, strategies for tailoring properties of low-dimensional MOFs-derived absorbers with hollow structures remain a considerable challenge. Herein, a well-defined Co@N-doped porous carbon composite (Co/N PC) with double-shell hollow structures has been successfully developed through self-templating-polymerization and subsequent pyrolysis. The proposed strategy for the synthesis of hollow architecture involves three simple steps (i) coordination, (ii) dissociation, and (iii) dopamine (DA) polymerization. The synthetic approach is realized at room temperature without a need for solvent etching. By effectively optimizing parameters including void thickness, surface structures, and graphitization levels, the as-designed Co/N PC composites feature wide absorption bandwidth of 5.93 GHz at a thickness of 2.4 mm with a filler loading of 15 wt%. The exceptional performance of microwave absorption (MA) is primarily achieved through excellent dielectric loss, and enhanced impedance matching, due to increased conductive loss through porous hollow structures and dipolar/interfacial polarization. This work provides an eco-friendly and facile route to designing hollow MOFs derivatives, offering substantial parameter space for optimized future lightweight and efficient absorbing materials.

Silicon-based anode materials with high theoretical capacity have great challenges of enormous volume expansion and poor electronic conductivity. Herein, a novel dual carbon confined SiOx/C@void@Si/C yolk-shell monodisperse nanosphere with void space have been fabricated through hydrothermal reaction, carbonization, and in-situ low-temperature aluminothermic reduction. Furthermore, the O/Si ratio and void space between SiOx/C core and Si/C shell can be effectively tuned by the length of aluminothermic reduction time. The SiOx/C core plays a role of maintaining the spherical structure and the void space can accommodate the volume expansion of Si. Moreover, the inner and outer carbons not only alleviate volume variation of SiOx and Si but also enhance the electrical conductivity of composites. Benefiting from the synergy of the double carbon and void space, the optimized VSC-14 anode affords prominent cycle stability with reversible capacity of 1094 mAh g-1 after 550 cycles at 200 mA g-1. By pre-lithiation treatment, the VSC-14 achieves an initial Coulombic efficiency of 93.27% at 200 mA g-1 and a reversible capacity of 348 mAh g-1 at 5 A g-1 after 4000 cycles. Furthermore, the pouch cell using VSC-14 anode and LiFePO4 cathode delivers a reversible capacity of 138 mAh g-1 at 0.2 C. We hope this strategy can provide a scientific method to synthesis yolk-shell Si-based materials.

Thermoelastic problems refer to a coupled phenomenon existing in a wide range of practical applications where elastic responses are influenced by temperature variation. Meanwhile, Moving Morphable Void (MMV) approach receives extensive attentions owing to explicit topological geometric information. In MMV method, a closed B-spline curve defined by several design variables is adopted to describe void material in design domain. In present study, we intend to use the MMV method to topologically optimize the thermoelastic structures under uniform temperature increment and varying temperature field. The weak formulations of heat conduction and elasticity are combined to describe the thermoelastic problems. The optimization mathematical model with the aim of compliance minimization and volume constraint is constructed. The sensitivity of design variables is derived by material derivative method and adjoint sensitivity analysis method. The method of moving asymptote (MMA) algorithm is implemented to update the design variables for finding the best material distribution. Numerical examples are provided to demonstrate the effectiveness of the proposed method.

This manuscript presents the case study of soft Bangkok clay improvement and simulations using combined vacuum pressures with pre-existing surcharge embankment preloading, including installations of air-tight membranes and horizontal prefabricated drains connected to the top of the PVDs as well as to the vacuum system with a modified air-water separation system. The 17-m-long PVDs were installed from the top of the embankment in a triangular pattern at a spacing of 0.9 m. Monitoring instruments were installed to measure surface settlements, lateral movements, and pore water pressures in the soft clay layer. The subsequent analyses included settlement calculations, settlement predictions using observational methods, flow parameter back-calculations, soil property comparisons before and after improvement, and FEM simulations. The very soft to soft clay was transformed to medium-stiff clay because its undrained shear strengths and maximum past pressures increased, and its water contents, void ratios, and compression indices decreased. The analyses of the degree of consolidation utilized one-dimensional and observational methods as well as a numerical simulation for the prediction of consolidation settlements and comparison to the field data. The results illustrated the effectiveness of the modified vacuum-PVD system. The findings could be used for guidance of similar soft clay improvement projects.

Thanks to their biocompatibility, biodegradability, injectability and self-setting properties, calcium phosphate cements (CPCs) have been the most economical and effective biomaterials of choice for use as bone void fillers. They have also been extensively used as drug delivery carriers owing to their ability to provide for a steady release of various organic molecules aiding the regeneration of defective bone, including primarily antibiotics and growth factors. This review provides a systematic compilation of studies that reported on the controlled release of drugs from CPCs in the last 25 years. The chemical, compositional and microstructural characteristics of these systems through which the control of the release rates and mechanisms could be achieved have been discussed. In doing so, the effects of (i) the chemistry of the matrix, (ii) porosity, (iii) additives, (iv) drug types, (v) drug concentrations, (vi) drug loading methods and (vii) release media have been distinguished and discussed individually. Kinetic specificities of in vivo release of drugs from CPCs have been reviewed, too. Understanding the kinetic and mechanistic correlations between the CPC properties and the drug release is a prerequisite for the design of bone void fillers with drug release profiles precisely tailored to the application area and the clinical picture. The goal of this review has been to shed light on these fundamental correlations., Graphical abstract Image 1, Highlights • Drug release from calcium phosphate cements (CPCs) for bone healing and regeneration. • Release of antibiotics, anti-inflammatories, chemotherapeutics, growth factors, and metallic ions. • Influence of different CPC formulations, matrix porosity, structure, and crystallinity. • Influence of matrix additives and the release medium. • Influence of the drug type, concentration and loading method.

The void closure model is urgently needed for the subsequent hot forming process of additive manufacturing (AM) products. The influence of temperature, Lode parameter, and hydrostatic integration (Gm) on void closure was studied by representative volume element (RVE) simulations. The results show that Gm and the Lode parameter significantly influence void closure, and the temperature effect is related to material properties. A new model accounting for Gm and Lode parameter in evaluating void closure was developed using linear regression with an average error of 2.1% in comparison to RVE simulations. X-ray computed tomography (CT) was carried out at different high reductions for the AM cylinder's hot forging experiments. The new and stress-triaxiality-based (STB) models were integrated into the ABAQUS and compared with the CT measurements. Results indicate that the model is more precise than the STB model, suggesting that the model can be appropriately applied to forecast void closure during the hot forging process for AM products.

This study focus on the physical characterization of short roselle fibre polymer composites. Short roselle fibre composites with 10%, 20%, 30% and 40% fibre content by weight were produced using the hand lay-up technique. Composite’s physical properties like density, void content and water uptake capacity were obtained as per ASTM standards. The void content of the composites ranges from 1.28 to 6.71%, which is quite low for short and randomly oriented composites. The saturation in water uptake was observed after 7 to 8 days of water immersion. The water uptake capacity of the roselle fibre composites increases with an increase in fibre content. It indicates the composites with the lower fibre content yield a higher resistance to water absorption.

Al6061 alloy nanocomposite reinforced with (0, 3, 6, 9 wt%) of nanozirconia were fabricated by stir casting technique. The physical properties such as void content, density and mechanical properties such as hardness, impact strength, flexural strength and fracture toughness were evaluated. It was found that nanozirconia has a significant effect as filler for the improvement in mechanical and physical properties. It was found that the addition of 3 wt% nanozirconia resulted in an increase in void content by 21%, hardness by 34%, impact strength by 32%, and flexural strength of 9.6 %. However, porosity was increased due to difficulty in mixing nanozirconia in the molten metal during stir casting. The addition of nanozirconia resulted in more strength, hardness and improved interface bonding between matrix and filler which led to improvement in fracture toughness.

The structural reliability of sintered products depends on large defects introduced during powder processing, which cannot be removed by pressureless sintering. Here, we present a model how a large single ellipsoidal void is deformed, and finally disappears by pressure-assisted sintering. Taya-Seidel’s model is applied to predict the shrinkage of a large void in a compressible linear viscous material by using bulk viscosity, shear viscosity, and sintering stress that are determined experimentally for sintering of alumina powder at low stress levels. The application of mechanical stress promotes the densification rate. Its effect is maximum for hot isostatic pressing (HIP) and minimum for sinter forging. The effect is intermediate for hot pressing (HP) and spark plasma sintering (SPS), because the hydrostatic component of stress varies with densification. While a crack-like defect can be removed during densification, a spherical void must be eliminated by shear deformation in the final stage during dwell time.

Carbon-fiber reinforced polymer composite materials are used throughout industry for their excellent mechanical properties; in particular, these composites boast high specific stiffnesses and specific strengths. However, current limitations on manufacturing, which vary greatly based on the technology that is utilized, restrict access to composite materials in a variety of applications. Traditional wet hand-layups offer a large diversity of viable constituent materials, but the fabrication geometry is limited and the manual process is time-consuming. In contrast, fiber 3D-printing (F3DP) allows for the production of complex geometries and requires little manual labor. In this study, laminates with continuous carbon fiber reinforcement printed using a commercially-available 3D printer are compared to carbon fiber fabric-resin composites produced using manual layup techniques. Cross-ply [0,90,0,90,0]T laminates were fabricated and subject to mechanical testing in uniaxial tension and flexure. After normalization with respect to fiber volume fraction, we found that the tensile strength and stiffness of cross-ply carbon fiber composites manufactured using F3DP were higher than the tensile strength and stiffness of cross-ply specimens manufactured by a traditional hand-layup method; however, the hand-layup specimens exhibited higher strength and stiffness in flexure. The difference in material properties evident between the two fabrication methods suggests that each has its own suitable application. We anticipate that further studying the failure response of printed, fiber-reinforced composite materials to various loading modalities will give insight into potential areas of improvement for F3DP material selection and printing processes, particularly relating to void reduction. On a broader scale, comparing and analyzing the mechanical properties of composite laminates produced in these various methods will provide perspective on the viability of novel additive manufacturing methods for large-scale production and industrial applications.

Considering that the particular geometric shape of a quasi-rectangular shield, the grout flowing law and its motion process are more complicated than those of a conventional circular shield. To interpret the grouting mechanical behavior in the special-shape shield tail void, the filling and diffusion mechanism of synchronous grouting was analysed. The grout flowing is separated into two independent motion processes, which contains a circumferential filling and a longitudinal diffusion. The theoretical model of the grout pressure spatial distribution was derived based on the principle of fluid mechanics. Then, the pressure distributions in the two directions were obtained using a case study and compared with the field measured data to verify the validation of the model. Although the overall spatial pattern of grout pressure distribution on the tunnel profile show a change trend dominated by the self-weight effect mostly, its local fluctuation characteristics is very abnormal relative to that of a circular shield tunnel. Moreover, the important factors in the model were analysed, including the grout material parameters, the grouting construction parameters, and some geometry parameters. The results show that the pressure loss along this way is positively correlated with the grout flow velocity and is sensitive to the shear yield stress of the grout. The pressure loss along the circumferential direction is the most sensitive to the thickness of the ring cake, and the value range suitable for the model should be 0.02–0.03 m. The pressure loss along the longitudinal diffusion direction is the most sensitive to the size of the tail void. The research results can provide a theoretical basis for the control of special-shape shield construction.

One of the causes of flexible pavement damage is being submerged in water with a high acidity, such as seawater. To overcome this condition, a study on the use of buton asphalt (as-buton) was conducted. The advantages of as-buton are that it has higher adhesion and is more resistant to temperature changes. As-buton modification by mixing Lawele as-buton Southeast Sulawesi with oil asphalt pen 60/70. This study focuses on determining the effect of the addition of as-buton to the modified asphalt mixture and the effect of seawater immersion on as-buton mixture based on the Marshall characteristic test. The percentage by weight of as-buton used is 5%, 7.5%, and 10%. The immersion was carried out in freshwater and seawater immersion for up to 24 hours at a temperature of 30°C. The result of this study show that the addition of as-buton increase the value of stability, void in mixture, Marshall quotient (MQ), and void in mineral aggregate, but reduce the flow, void filled with asphalt, and density. The increase of stability and MQ value in seawater-immersion due to the addition of as-buton was higher than that in freshwater. The stability value of the 10% modified as-buton mixture in freshwater-immersion increased by 169.338 kg (14.61%) and in seawater-immersion increased by 1261.669 kg (55.65%). The flow value in freshwater-immersion decreased by 1.9 mm (25.33%) while in seawater-immersion decreased by 1 mm (14.08%). For further research, variations in the addition of as-buton will be carried out to produces a modified asphalt mixture.

Air voids in concrete tend to cluster around coarse aggregate particles and potentially weaken the concrete. This study explored key factors influencing air void clustering and evaluated the effect...

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.

Standard text-book dislocation theory for the elastic fields of a dislocation is provided in an infinite medium. For problems involving free surfaces, or image stresses, the solution for such elastic fields is more complex. The current article extends the state of knowledge for problems with free surfaces to address the stress field of a screw dislocation in a plate (two planar free surfaces) containing a hole/void. Such surfaces interact and thus affect the stress field of a dislocation in deviation of the infinite medium solution. The numerical solutions provided herein, based on reflective image stresses and the collocation-point method, have been verified to the extent available and such solutions allow for further applied problems. One main finding of the paper is that the equilibrium location of a screw dislocation is always closer to the hole/void surface than the planar free surface.

Pervious concrete is not environmentally friendly due to presences of non-renewable material in its production. Pervious concrete has made a comeback as a green infrastructure and researchers came up with a proposal to use waste materials that potentially to work well as material in pervious concrete. The used of palm kernel shell (PKS) in pervious concrete is consider brilliant because Malaysia is of the larger oil palm producer in the world. In this study, natural aggregate was partially replaced by 0, 10, 15, and 20% by weight of PKS aggregate to produce lightweight pervious concrete based PKS. The testing conducted comprise of density, void content, compressive strength, and flexural strength. Inclusion of PKS aggregate reduces the mechanical properties of pervious concrete but significantly higher than recommended in the standard, utilizing some PKS aggregate as partial aggregate at up to 20% substitution level can produce lightweight PKS-pervious concrete. The pervious concrete containing 10% of PKS aggregate presented the most optimum mixture. Besides, the use of PKS as aggregate replacement in pervious concrete mixture indicates a good potential towards sourcing alternative sustainable materials for concrete.

The expectations over composite materials have been increased especially in automotive and aerospace applications due to its high strength to weight ratio and good mechanical properties. Here, we aim to fabricate a hybrid composite of high strength and low density for automotive application to suits the above needs. In this investigation, the heat-treated aluminum alloy Al–Mg–Si-T6 was initially reinforced with industrial waste fly ash particles at five different weight fractions of 0%, 5%, 10%, 15% and 20%, respectively by stir casting process. The mechanical properties such as tensile strength, compression strength, hardness and density were tested, and microstructure of the composite was evaluated to explain the mechanical properties evolution. From the results, it was concluded that the composite with 10% fly ash shows enhanced at maximum the properties when compared to others. Then, the Al–Mg–Si-T6 – 5% fly ash was further reinforced with boron carbide particles by using three different fractions of 2.5%, 5% and 7.5%, respectively by stir casting process. The microstructural analysis, Scanning Electron Microscope analysis (SEM) and Energy Dispersive X-ray Spectroscopy analysis (EDS) were carried out for the casted samples to evaluate interfacial bonding, agglomeration, clustering and void formation in the hybrid composite samples. The casted samples were also tested for mechanical properties such as tensile strength, compression strength, hardness and density. It reveals that the optimal combination of 10% reinforcement (5% fly ash and 5% boron carbide) shows 18.7% higher tensile strength, 11.3% higher hardness and 38.6% higher compression when compared with the unreinforced Al–Mg–Si-T6 heat treated alloy. It is expected that the present hybrid metal matrix composites can be adopted for the fabrication of drive shaft in race cars.

In this paper, three different scenarios were experimentally investigated to compare carbon dioxide based enhanced oil recovery methods. These methods are continuous carbon dioxide (immiscible injection), water alternating gas, and cyclic carbon dioxide injection were investigated. In scenario A, the maximum oil recovery factor for water flooding is about 19% when there is no oil production. The maximum oil recovery at miscibility stage is about 46%. The reason for this low value of oil recovery factor might correspond to the sufficient interaction time between oil and dissolved gas. In scenario B, the total oil recovery factor is about 60% when the water alternating gas injection was performed in the system. In scenario C, after cyclic carbon dioxide injection, final oil recovery factor reached to 62%. The maximum oil recovery after miscibility stage is about 78%. In scenario B and C, regarding the more oil volume production, there are more void spaces that can be a good place for carbon dioxide storage. However, for scenario B, as the injection pattern has been changed alternatively, the void spaced had been occupied by water and this is why the carbon storage capacity was being decreased for this scenario rather than other two scenarios.

In this study, the two-phase pressure drop in a one-sided high-heat-loaded screw tube was analyzed under subcooled flow boiling conditions. When the loaded heat flux is gradually increased under one-sided heating conditions, although the pressure drop changes slightly in the single phase, it starts to increase when loading above the onset of significant void (OSV) heat flux. The effect of system parameters on the two-phase pressure drop in relation to the change of heat transfer mechanism or fluid properties was analyzed according to each variable change. In addition, this study evaluated the prediction performance of existing two-phase pressure drop multiplier correlations developed under subcooled flow boiling conditions. Because most existing correlations are based on a smooth channel with a small diameter, they tend to overpredict the experimental values. The correlation proposed by Ramesh showed the lowest average error rate (31.94%); however, the results were underpredicted for high-heat-flux conditions. To obtain more accurate results, we developed a Python code using an artificial intelligence regression method to proceed with the optimization process based on the experimental values. Using this code, we developed a novel two-phase pressure drop multiplier correlation for a one-side-heated screw tube that can be used in fusion divertors under high-heat-load conditions.

This paper proposed an algorithm to reconstruct the microstructure of asphalt mixture considering dynamic arrangement process of aggregate particles. In this method, asphalt mixture was considered to be composed of dispersed phase including coarse aggregate and air voids, and continuous phase including fine asphalt matrix (FAM). The dispersed phase materials were characterized by high-dimensional polyhedral particles. In order to reconstruct the microstructure by 1:1 in volume fraction, three basic parameters that determine the heterogeneous structure of asphalt mixture were abided in the design of digital specimen. Then, impulse-based rigid collision response was introduced to simulate the rearrangement of aggregate particles in the compaction process of asphalt mixture. In particular, the applicability of the proposed method to typical structural types of asphalt mixture was discussed. For the asphalt mixture with high air void content, the reconstructed specimen may deviate from the real structure. Furthermore, the dynamic modulus and thermal conductivity of the generated specimens were predicted by finite element method (FEM) and compared with the experimental values. The predicted dynamic modulus and thermal conductivity coincide with the experimental results well, which indicates that the proposed method is reliable for reconstructing the heterogeneous structure of asphalt mixture with relatively low content of air voids.

Many rate theory models of cavity (void) swelling have been published over the past 50 years, all having the same, or similar, structures. A rigorous validation of the models has not been possible because of the dearth of information concerning the microstructures that correspond with the swelling data. Whereas the lack of microstructure information is still an issue for historical swelling data, in the past 10–20 years data have been published on the evolution of the microstructure (point defect yields from collision cascades, cavity number densities, and dislocation densities/yield strengths) allowing certain gaps in information to be filled when considering historic swelling data. With reasonable estimates of key microstructure parameters, a standard rate theory model can be applied, and the model parameter space explored, in connection with historical swelling data. By using published data on: (i) yield strength as a function of dose and temperature (to establish an empirical expression for dislocation density evolution); (ii) cavity number densities as a function of temperature; and (iii) freely migrating defect (FMD) production as a function of primary knock-on atom (PKA) spectrum, the necessary parameter and microstructure inputs that were previously unknown can be used in model development. This paper describes a rate-theory model for void swelling of 316 stainless steel irradiated in the EBR-2 reactor as a function of irradiation temperature and neutron dose.

The purpose of this test is to determine the aggregate characteristics of the Pucak river as Aus Layer Laston Mixture. So, several series of studies were used, starting from testing aggregates (coarse and fine), asphalt and filler, then making compositions to making samples of Laston Wear Layer. The results of this study are to determine the characteristics of the pavement material using aggregate from the Pucak River Maros Regency to meet the requirements of the 2018 General Bina Marga specification, to be used in road layers. Based on the Conventional Marshall test, the Stability, Meltability (flow), Void In Mix (VIM), Void In Mix Aggregate (VMA), and Foid Filled With Bitumen (FVB) all values obtained meet the General Specifications of Highways 2018. And testing Marshall Immersion in the Aus Layer Laston mixture meets the 2018 Highways General Specifications, where the value of the Marshall Remaining Stability is 94.50 ≥ 90%.

Metal phosphides with a high theoretical capacity and low redox potential have been proposed as promising anodes for potassium-ion batteries (PIBs). A reasonable configuration design and introduction of a hollow structure with adequate internal void spaces are effective strategies to overcome the volume expansion of metal phosphides in potassium-ion batteries. Herein, we report a cage-confinement pyrolysis strategy to obtain hollow nanocage-structured nitrogen/phosphorus dual-doped carbon-coated copper phosphide (Cu3P/CuP2@NPC), which exhibits a high initial charge capacity (409 mA h g-1 at 100 mA g-1) and an outstanding cycle performance (100 mA h g-1 after 5000 cycles at 1000 mA g-1) as an anode material for PIBs. The novel hollow nanocage structure could prevent volume expansion during cycling and reduce the electron/ion diffusion distance. Besides, the nitrogen/phosphorus dual-doped carbon-coated layer could promote electronic conductivity. In situ X-ray diffraction (XRD) measurements are conducted to study the potassiation/depotassiation mechanism of Cu3P/CuP2@NPC and reveal the structure stability during the cycle process, which further proves that the design ideas of the conductive carbon layer and the hollow structure with adequate internal void spaces are successful.

This study aims to determine whether the decision of West Jakarta District Court which decided Loan Agreement between Nine AM Ltd. with PT. Bangun Karya Pratama Lestari is null and void according to the law of treaties or not and to know the legal implications of the West Jakarta District Court decision in Case Number 451 / Pdt.G / 2012 / PN.Jkt.Bar about the cancellation of loan agreements. This research using normative legal research by the statute approach and a case approach. The results of this study were 1) the West Jakarta District Court decision was in accordance with the law of treaties that the agreement is null and void. This decision caused by the Loan Agreement was infringing Article 1320 of the Burgerlijk Wetboek, that is not the fulfillment of the elements of a cause of the lawful and contrary to Article 31 of Act number 24 of 2009 concerning Flag, Language, and The State Emblem and Anthem Language and Article 1339 of the Burgerlijk Wetboek which provides that an agreement is not only bound to what is explicitly approved in the agreement, but also bound by propriety, customs, and laws. 2) Juridical implications of that decision is any agreement that is not made in accordance with the provisions of Article 31 Act number 24 of 2009 concerning Flag, Language, and The State Emblem and Anthem will be declared null and void / agreement is deemed never existed and the parties returned in original condition. Likewise with any follow-up agreement (assumed as accessories) will be declared null and void anyway, even the agreement made with the competent authority knowing it.

The Al-6063/Graphite composite was processed by the stir casting technique. The graphite was copper-coated using a cementation process and introduced into the matrix at 2.5, 5, and 7.5 wt%. The microstructure and the hardness of the composite were examined. The micrographs showed better particle distribution for the graphite reinforcements up to 5 wt%. Further increment resulted in inhomogeneous particle distribution and increase in % void content. The uniaxial compression test was performed to investigate the plastic flow properties. It was observed that an increase in the graphite reinforcement decreased the flow strength. However, the true fracture strain to failure increased. Furthermore, the effect of graphite reinforcement on the friction factor ‘m’ was analyzed by a ring compression test. The test was performed at various temperatures from 373 to 673 K in the interval of 100 K, including the ambient temperature. It was observed that the graphite reinforcement had a considerable effect on reducing the friction factor during deformation, up to 473 K.

The multi-scale characteristics of particle morphology, including the overall form, local roundness and surface roughness, affect the critical state behavior of sands and should be considered in modern critical state-based continuum constitutive modeling. Despite extensive experimental and numerical studies, no consensus has been reached as to how particle morphology may quantitatively dictate the critical state response of sands. This study presents a numerical investigation based on discrete element method (DEM) in an attempt to address this outstanding issue. Five DEM samples of uniformly graded sands consisting of realistic shape clumps and ideal spheres of different mass proportions are prepared and subjected to conventional drained and undrained triaxial compression under different initial void ratios and stress states. A 3D overall regularity (OR) index is adopted to quantify both the overall form and local roundness characteristics of these assemblies. It is shown that this shape parameter OR may effectively help to elucidate the correlation between mechanical properties, especially the critical state behavior of sand and particle shape, and has a great potential for incorporation into the framework of anisotropic critical state theory for constitutive modeling of sand behavior. The study helps to advance our cross-scale understanding of microscopic grain-scale morphology information in relation to macroscopic soil behavior.

In this study, an analytical model is developed to establish a framework for predicting the coefficient of lateral soil pressure in unsaturated soils. To this end, the disturbed state concept (DSC) is implemented along with the concept of effective stress for unsaturated soils. Accordingly, upper and lower limits are considered for the structural disturbance of the soil during hydromechanical loading, and a suction-dependent analytical framework is proposed for calculating continuous variations of the coefficient of lateral soil pressure, from the at-rest to active state of the soil, against the effective vertical stress parameter. The functionality of the proposed model is verified against experimental results obtained from a series of laboratory unsaturated drained tests conducted on two different soil materials (a Sand–Kaolin mixture and Firouzkouh Clay) with two initial void ratios. Quantitative comparisons show excellent conformance between the predicted and experimental data. A practical example of calculating lateral soil pressure on a gravity retaining wall is also presented, in which the results obtained from the model presented in this study and the conventional classic approach of calculating the lateral soil pressure on retaining walls are compared. It is hoped that the results of this study can help researchers and designers to obtain improved values of lateral soil pressure in unsaturated soil.

Even though rejecting the notion of void, Aristotle considers it a crucial theme in his discussion about motion. That becomes evident when we find four chapters of Physics 4 dedicated to the discussion and refutation of the void. In this paper, I set on an exploratory search for the reasons that moved Aristotle to discuss the idea of void as a container (ἀγγεῖον) in Phys. 4.6 213a15-19, unearthing a series of terms and notions used by previous thinkers that may have led Aristotle to formulate such conception. Special attention is given to Democritus, who, with his theory of atoms and void, is clearly the main target of Aristotle’s criticism of the void. I conclude that the notion of void as a container is not at all strange to ancient thinkers, and that its reconstitution by Aristotle is everything but trivial and simplistic, inasmuch as the Democritean notion of void he intends to refute is everything but trivial and simplistic.

With the coal mining toward depth, there is an increased probability of gas explosion accidents. While the propagation characteristics of gas explosion on account of goaf environment have not been ...

A cursory review of literatures shows a void in regional patterns analysis of rural livelihood in the sub-Himalayan West Bengal, India. Therefore, this study has attempted to examine the regional pattern of multidimensional rural livelihoods (assets, accessibility, health and education) in the study area. The study has attempted to look at the various determinants that make a region different from others in the same geographical space in terms of livelihood practices and household well-being. The study has applied a mixed research method, that is, Principal component analysis (PCA), household well-being indicator approach, multiple regressions, and focus group discussions (FGDs). The community blocks of the study area are found to be differently endowed in terms of different assets. The results show that marginalised castes and non-Hindu households have a relatively lower well-being score than the other households. The results suggest that daily work opportunities and an increase in the number of casual labourers positively impact the generation of decent and sustainable livelihood. It also shows an increase in the household well-being score to occupation groups such as businesses and salaried jobs. However, collection of sandstone and other construction materials from the river bed is emerging as a new source of livelihood.

In this study, a validated CFD model is used to analyze the flow field and pollutant distribution in an isolated canyon (street aspect ratio, W/H = 1) by considering different street categories and arrangements of void deck under a perpendicular inflow wind. The results reveal that the street geometry affects significantly the in-canyon flow structures and thus the pollutant distributions. Comparing with the regular street canyon (a main clockwise vortex is obtained therein), the void deck can cause several vortices when a strong stream of air passes through the canyon. It is the most conducive to pollutant removal for the void decks at both buildings, while the construction with void deck at the upstream building causes pollutant accumulation on the windward side. Moreover, a larger high-pollution zone is generated above the elevated road due to the wind recirculation therein, and for the two-level street and the street with depressed road, the weak wind leads to the accumulation of traffic pollutants in the underground space. This study will provide technical support for urban street planning and design to alleviate traffic pollution.

In this paper, a short review on the void and moisture content studies of fiber reinforced composites for both, synthetic and natural based fibers are presented. The review summarized the research papers in which include experimental and theoretical works that related to the void and moisture content studies. In addition to that, this review paper highlighting a few research studies conducted in literature on the effects of the void and moisture on the mechanical performances of the composite. Few common measurement methods used for the void and moisture determination are discussed here. The aims of this short review, mainly to capture the trend ranging from the recent five years back and summarize the various studies and also to compare and conclude the most common method for the determination of the void and moisture content. This paper is mainly providing a baseline in the selection of the methods for the future work of the author’s work with regard to the reduction of the presence of voids and moisture occur during the impregnation process of fiber reinforced composites, especially when using natural-based fiber.

Objective(s): To evaluate the “flow void” diameter in patients with pregnancy-related diseases with and without uterine AVMs and assess the diagnostic performance of unenhanced MRI for uterine AVMs.Study Design: From May 2014 to April 2019, 79 patients with pregnancy-related diseases were included, including 36 with and 43 without uterine AVMs confirmed by DSA. On MRI, the diameter of the most prominent “flow void” (hereinafter referred to as fv-D) was measured and compared between patients with and without uterine AVMs. The diagnostic performance of fv-D was estimated with receiver operating characteristic curves.Results: The “flow void” sign was observed in patients with and without uterine AVMs (P>0.05). The fv-D was significantly larger in patients with uterine AVMs in the myometrium and parametrium than in patients without uterine AVMs (P1.33 mm) and parametrium (sensitivity: 97.22%, specificity: 67.44%, AUC: 0.881, cut-off:>2.6 mm). Conclusions: On MRI, fv-D could diagnose uterine AVMs. The fv-D had a much higher diagnostic efficiency in the parametrium than in the myometrium. The parametrium fv-D greatly improved the diagnostic sensitivity and provides a more accurate, noninvasive method of investigating possible uterine AVMs.

The Al2TiO5 particles reinforced Ag–CuO–Al2TiO5 composite filler metal prepared by mechanical milling was applied to reactive air braze ZrO2 ceramic to itself. The effect of Al2TiO5 particle content and brazing parameters on the interfacial microstructure and mechanical properties of the joints was systematically analyzed. Moreover, the stability of joint microstructure and the variation of bonding properties were investigated by subjecting them to prolonged heat treatment at 800 °C. The results show that the shear strength of the reactive air brazed joints at 1050 °C for 30 min with 10 wt % Al2TiO5 additives reached 104 MPa, which was 112% higher than that of the joints brazed with single Ag–CuO filler metal. The added Al2TiO5 particles were decomposed into TiO2, which was further reacted with ZrO2 ceramic to form ZrTiO4 phase and blocky Al2O3 phase in the Ag matrix and thus generating the particle-reinforced brazing seam. The variation of joint shear strength caused by brazing parameters and Al2TiO5 contents was analyzed from the viewpoints of the wettability of composite filler, microstructural evolution of joint and formation of void defect. When the ZrO2 ceramic was brazed with Ag–CuO-10 wt % Al2TiO5 at an optimized parameter of 1050 °C for 30 min, the joint shear strength did not decrease obviously after oxidation at 800 °C for 100 h because of the good high-temperature stability of the joint microstructure.

Summary Metal penetration into a solid electrolyte (SE) is one of the critical problems impeding the practical application of solid-state batteries. In this study, we investigate the conditions under which electronic conductivity of the SE can lead to metal deposition and fracture within the SE. Three different stages for void filling (metal plating initiation, metal growth, and metal compression) in the SE are identified. We show that a micron-size isolated void in the SE near the anode can be quickly filled in by metal and fractured when the developed pressure in the void grows larger than the maximum pressure the SE material can sustain. We find that the anode voltage and applied current density play a significant role in determining the vulnerability to metal deposition. We discuss several strategies to prevent electronic conductivity-driven metal propagation in electrolytes that are not fully dense, including the densified layers between the anode and SE.

SnO2 is considered as a promising anode material for lithium-ion batteries (LIBs) in view of its high theoretical capacity. However, the large volume change and low reversible capacity of SnO2 anode have restricted its practical application. In this study, the two issues were overcome by fabricating SnO2-carbon composite with an optimized structure: SnO2/carbon nanoclusters, composed of ultrafine SnO2 nanocrystals and carbon boundary, with well-defined interlayer void space were monodispersed encapsulated in graphene-supported carbon framework (denoted SCVC composite). The nanoscale interlayer gap could buffer volume expansion of SnO2. The numerous carbonaceous boundaries between ultrafine SnO2 nanocrystals could prevent Sn/LixSn coarsening, guaranteeing sufficient Sn/Li2O interdiffusion and enhancing conversion fraction of Sn and Li2O to SnO2 during charging. While the graphene-based carbon framework would enable a fast ion/electron transport and stable solid electrolyte interface. As a result, the SCVC-based LIBs delivered a high reversible capacity, ultralong cycling life-span and excellent rate capability. A capacity of 643 mAh g−1 at 5 A g−1 was retained after 1000 cycles for the SCVC anode. A high reversible capacity accessibility of 1239 mAh g−1 could be reached at 0.5 A g−1 for the SnO2 component in SCVC anode.

The effect of ferrite and martensite hardening variation on the mechanism of void formation in a low-carbon low-alloy steel with different ferrite–martensite dual-phase (DP) microstructures has been investigated. Accordingly, several ferrite–martensite DP microstructures containing a wide range of martensite volume fractions (Vm) from 23% to 87% were developed by application of intercritical annealing heat treatment processes. Optical and field-emission scanning electron microscopy were supplemented by hardness measurements and tensile testing to follow the microstructural changes and correlate them with the mechanism of void formation. The experimental results indicate that the mechanism of void formation changes from ferrite/martensite (F/M) interface decohesion to martensite cracking as Vm increases in the microstructures. For DP specimens containing low Vm, F/M interface decohesion is the dominant mechanism of void formation, while in DP samples with moderate level of Vm, both mechanisms of F/M interface decohesion and martensite cracking are involved in the void formation. In DP samples containing high Vm, void nucleation and growth due to martensite cracking is the dominant damage mechanism. This change in the void formation mechanism with Vm can be rationalized based on the change in the plastic behavior of ferrite and martensite microphases developed as a consequence of ferrite and martensite hardening variation. The martensite hardening response decreases monotonically with increasing Vm from 23% to 87%, while that of ferrite shows an increasing trend up to 73% then decreases with further increase up to 87%.

A phenomenological ductile fracture model is proposed by a careful consideration of void nucleation, growth and coalescence during plastic deformation. Within the model framework, void nucleation is controlled by an equivalent plastic strain function. Void growth takes place through two ways, namely void dilation and void elongation, which are characterized by the normalized hydrostatic stress and normalized maximum shear stress, respectively. Void coalescence is characterized by the maximum shear stress. Aluminum alloy (AA) 6016-T6 sheets are selected to conduct ductile fracture (DF) experiments on specimens with different geometries, which can cover a wide range of stress states from simple shear to balanced biaxial tension. Subsequently, the new DF model is calibrated by using a robust hybrid numerical-experimental approach with a three-dimensional (3D) fracture surface constructed for AA 6016-T6. Ductile fracture data of other two aluminum alloys (AA 2024-T351 and AA 5083-O) are also used to evaluate DF model performance by establishing their 3D fracture surfaces. Finally, a cup drawing test is conducted and simulated as a case study showing how an applicable way of using the new model. Furthermore, the predictive accuracy of the proposed DF model for fracture initiation is compared with other three uncoupled models (modified Mohr–Coulomb criterion (MMC), Lou-Yoon-Huh model and Mu-Zang model) by ABAQUS/Explicit with a user subroutine (VUMAT), which shows a good performance of the proposed DF model.

Tamusu mudstone, located in Inner Mongolia, is being recognized to be the potential host formation in deep HLW disposal across China. This paper describes diverse laboratory experiments performed using the fractured Tamusu mudstone, with concern to the study of the combined mechanical and thermal effects on its hydraulic properties, as well as its self-sealing effect. A single rough fracture is generated down the sample diameter direction before the sample’s installation. Considering a heating-cooling cycle, the evolution of the samples’ hydraulic properties under different stress conditions has been monitored. The hydraulic conductivity is proved to be not only related to the temperature-induced water viscosity and density variation but also the change of stress state. At the same thermal conditions, the increase of confining pressure (or deviatoric stress) may weaken the flow capacity of the fractures and thus reduce the permeability. The non-coincidence for the curve of permeability versus temperature at the heating and cooling stage indicates that the permeability alterations in the fractures are irreversible. Fracture zone changes were observed by X-ray computer tomography (CT) before and after the tests. The self-sealing behavior, which may be beneficial from high confining pressure, was detected for fractured Tamusu mudstone. Morphologies of fracture surfaces were detected by the 3D scanning technique, which shows that the fracture surface roughness, due to the alteration of asperity contacts and void spaces under high stress, may take an important part of the responsibility to the change of permeability.

As a common phenomenon in granular flow, grain segregation plays a great role in affecting the behavior of granular soil by causing a great change of grain-void distribution in granular soil. This paper presents an experimental study on the influence of grain segregation on the behavior of sand, by a number of triaxial tests to interpret the characteristic behavior, friction and dilatancy behavior, excess pore water pressure behavior and critical state behavior of sand incorporating grain segregation. An index - grain segregation index Igs was proposed to quantify grain segregation. Grain segregation affected greatly the characteristic behavior of sand, causing the movement of void ratio-dilatancy relation of sand towards the increase of void ratio and dilatancy of sand. In the drained tests, the mobilized friction angle of sand showed a decrease followed by an increase but the mobilized dilatancy angle of sand increased, with increasing grain segregation index. An increase in grain segregation index impaired the basic friction of sand. In the undrained tests, the mobilized friction angle of sand showed an increase followed by a decrease with increasing grain segregation index. However, grain segregation caused an increase of the mobilized dilatancy of sand followed by a different development. An increase in grain segregation resulted in a higher summit of the dilatancy of sand but with a faster decrease along axial strain. In the q-p′ plane, grain segregation caused a reciprocating rotation of the dilatancy line and failure line of sand. Grain segregation resulted in enhancement of the peak-state dilatancy of sand, affecting greatly peak-state friction angle and peak-state basic friction angle of sand as well as the normalized excess pore water pressure. The excess friction angle of sand showed an increase followed by a decrease in the drained tests but increased linearly in the undrained tests, with increasing grain segregation index. The excess friction angle-over-maximum dilatancy angle of sand decreased in up convexity while increasing grain segregation index. Grain segregation resulted in rotation and translation of the critical state line of sand in the e-p′α=0.7 plane. However, in the q-p′ plane, the critical state line of sand showed an anticlockwise rotation followed by a clockwise rotation with increasing grain segregation index.

Experimental data show that the accumulation of rhenium and osmium from transmutation reactions severely affect the microstructural evolution and property degradation of tungsten-based materials under neutron irradiation. Theory and modeling have confirmed that Re atom transport in W is by irradiation-produced migrating self-interstitial atoms. With this diffusion mode in operation, a specific microstructure evolution is realized when at relatively low neutron fluence the Re-rich precipitates are formed, while the void and interstitial loop population development is suppressed, affecting the mechanical properties. This research shows the effect of small coherent Re-rich precipitates on the dislocation glide under stress, investigated using the molecular dynamics approach with empirical interatomic potentials. The results are compared with an earlier simulation of void hardening in W. It is demonstrated that small coherent Re-rich precipitates of less than 6 nm diameter represent relatively weak obstacles for moving edge dislocations. The implication of these results on the interpretation of experimental results is discussed.

In microgravity, the astronaut’s body is suspended in a void, separated from its surroundings except where measures have been taken to tether it to a surface. The experience of weightlessness can b...

Direct-ink-writing type additive manufacturing with water-based inks such as hydrogels or polymer solutions is broadly utilized for bioprinting applications. However, the resolution of this implementation is limited due to the rapid ink drying experienced at small size scales leading to nozzle clogging and low fidelity prints. To address this issue, a humidity-controlled direct-ink-writing (HCDIW) approach is presented, where the microenvironment around the printing nozzle is controlled through introduction of aerosolized water. Using this approach, the nozzle microenvironment can be varied between undersaturated yet high relative humidity (ambient to 100% RH) to oversaturated conditions where condensing droplets are deposited on the already printed ink filaments. The influence of the aerosolized water and the resultant micro-environment on the printing process was studied using water dissolved sodium carboxymethyl cellulose (NaCMC) ink, specifically focusing on nozzle clogging, printed filament geometry, surface quality and layer by layer stacking. These studies showed that the ink drying induced nozzle clogging issues can be mitigated through increased relative humidity at the nozzle exit and is virtually eliminated for ~100 μm nozzles in oversaturated conditions. The decelerated ink drying under the effect of aerosolized water leads to reduced solute advection and skin formation. This in turn improves surface roughness while reducing adverse effects such as coffee-ring and void formation during additive manufacturing of micro-scale structures. Furthermore, layer-to-layer fusion and associated side-surface quality were improved specifically in undersaturated conditions. Reduction of deposited ink filament concentration in oversaturated conditions leads to excessive spreading of the deposited inks leading to geometric distortions. These results indicate that the humidity control approach can significantly improve the resolution of the direct-ink-writing approaches, enabling processing of water-based inks at micro-scales.