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Summary The simulation of the in-situ conversion process (ICP) is a challenging endeavor that involves complicated thermal-reactive-compositional coupling processes. The upscaling of ICP simulation has been investigated, but the developed methods have significant limitations, which hinder their use in complicated models. The most constraining limitation of previous ICP upscaling techniques is that they all require modifications of the simulation code, which make them difficult to use in closed-source commercial simulators. In this paper, we introduce a novel upscaling method for ICP simulation. In this new method, we introduce two correction factors (namely α and β in this paper) to adjust the coarse-scale reaction frequency factor and activation energy. The calculation of the two factors is based on the reactions on both coarse-scale and fine-scale models. The new upscaling method does not entail any additional modifications of the underlying simulation source code, and thus it is more feasible to implement. We demonstrate the accuracy and efficiency of our upscaling method with 2D and 3D models, respectively. Apart from model dimensions, the availability of the novel upscaling method for ICP simulations with different values of kinetic parameters is considered as well. It is shown that the novel upscaling method provides reasonably accurate results, and significant computational savings are also achieved.

The battery is an important part of the new energy electric vehicle, and the control of the flatness of its side plate/bottom plate is the key to quality improvement in mass production. However, there are few pieces of research on the flatness distribution form at present, and the distribution form is often assumed to be a normal distribution, which leads to a significant deviation between the tolerance design and quality control of the flatness and the reality. This paper establishes a statistical model of flatness distribution, its theoretical distribution form is deduced as a normal range distribution, and then the experimental data of the flatness distribution are collected to verify this conclusion. Determining the flatness distribution form has practical effects on improving manufacturing quality and reducing costs in battery manufacturing.

Gossan ore is typically abandoned after mining, which not only increases mining production costs but also wastes mineral resources, and its long-term accumulation can easily lead to environmental pollution hazards. Therefore, this paper takes zinc-containing gossan ore as the research object and, based on the high content of zinc and iron minerals in gossan ore, this study conducts a roasting experiment to prepare ZnFeO4. X-ray diffraction is used to characterize and analyze the ZnFeO4 sample prepared by roasting zinc-containing gossan ore. The experimental results indicate that controlling the particle size of the roasted ore sample to −0.074 mm can effectively remove impurities and facilitate the reaction. The influence of roasting temperature and time on the formation of ZnFeO4 is remarkable. The conditions for roasting zinc-containing gossan ore to maximize the ZnFeO4 content are as follows: −0.074 mm particle size ore sample, reaction zinc/iron molar ratio of 1:2, mechanical activation time of 120 min, roasting temperature of 1050 °C, and roasting time of 120 min. These findings provide new ideas for the utilization of gossan ore and lay a theoretical foundation for the efficient development and utilization of difficult-to-select zinc-containing gossan ore.

To improve the adjuvant activity of polysaccharides from Eucommia ulmoides leaves (PsEUL) in inducing an effective immune response against ovalbumin (OVA), PsEUL were conjugated to OVA using the N-(3-dimethylaminopropyl)-N'-ethylcarbodiimide hydrochloride (EDC) method. The synthesized PsEUL-OVA was encapsulated using phytantriol and F127 to produce PsEUL-OVA cubosomes (Cubs), a novel delivery system. The physicochemical properties and immune modulation effects of this novel delivery system were explored.In vitro, PsEUL-OVA/Cubs carrying large amounts of OVA were rapidly phagocytized by macrophages and upregulated macrophage proliferation, thereby stimulating cytokine production (interleukin (IL)-6 and IL-4). In vivo, PsEUL-OVA/Cubs increased the titer of OVA-specific antibodies (immunoglobulin (Ig)G, IgG2b, IgG2a and IgG1) and cytokine levels (IL-2, IL-6, IL-4 and interferon-γ). In addition, the cubosomes promoted the differentiation of CD8Collectively, the findings demonstrate that PsEUL-antigen/Cubs can be a useful delivery vehicle with immune response-promoting effects. Therefore, this study lays the foundation for the development of novel adjuvant-antigen delivery systems with potential applications in vaccine design. © 2022 Society of Chemical Industry.

Until recently, there have been limited alternatives and competition to hotels for leisure or business travelers who are looking for long term accommodation. Increased globalization of businesses and changing work practices are requiring business professionals to carry out their work away from home on a short to medium basis. Serviced apartments have grown in popularity as they do offer a different concept in alternative accommodation. What is presented as the most interesting element about this concept to investors is how it differs from hotel accommodation in terms of their product offering, the valuation considerations as well as their investment criteria. The paper seeks to examine the history and development serviced apartments in the various regions of the world and how the investments in this new sector has evolved in the creation of a whole new market. The article will present the argument that the innovation and expansion of the serviced apartment sector has boosted profitability, demand profile and competition in the accommodation market.

Summary The shape, size, and orientation of natural fractures significantly impact the geometry of hydraulic fractures in unconventional reservoirs, such as shale gas/oil, tight gas, and enhanced geothermal system. The behaviors after the hydraulic fracture encounters natural fractures have been summarized as crossing, diverting, step over, and stopping based on a great number of numerical and experimental analysis with plain strain assumptions. However, under practical situations, the geometries of natural and hydraulic fractures are much more complex than the vertical and rectangular shape assumed by 2D models. The experimental studies on the role of height and inclination of natural fractures have revealed some other phenomena (e.g., bypassing process that the fluid-driven hydraulic fracture propagates up the back side of the natural fracture), which are unable to be captured in 2D. To better describe the intersection behaviors among different kind of fractures, a fully 3D model based on the displacement discontinuity method (DDM) is developed on top of our previous models, which only considered the propagation of hydraulic fractures. A novel crossing criterion to judge whether the hydraulic fracture will cross the cemented natural fracture in 3D is proposed. The successive node snapping scheme is adopted to construct conforming meshes for the evolving intersected curves between hydraulic and natural fracture surfaces, which only alters the location of a small fraction of nodes without changing the nodal connectivity. With this model, the evolution of fracture geometry after the hydraulic fracture intersects with the natural fractures of different toughness, size, orientation, and number is investigated. Because an extra dimension is considered, the fractures are allowed to propagate in more directions, resulting in a series of complex fracture geometries. The dynamic grid evolution method proposed in this work can promote the development of DDM in modeling fully 3D fracture networks in naturally fractured reservoirs.

Hydraulic fracturing is a commonly adopted approach to enhance the production of unconventional reservoirs; however, the resulted complex fracture network increases the difficulty in the prediction of the flow behaviors. In this work, for the first time, we propose the Laplace-transform embedded discrete fracture model focusing on the simulation of fluid transport in simulated reservoir volume (SRV). The main hydraulic fracture is represented explicitly by the fracture segments referring to the recently developed simulation scheme, namely the embedded discrete fracture model. The equivalent model and multiple continua model are employed to characterize the fluid flow in SRV. The Laplace-transform finite-different method is used to numerically model the flow among unstimulated reservoir volume, SRV, and main hydraulic fracture with sufficient flexibility to characterize the arbitrary fracture/SRV geometries. As the solution is performed in Laplace domain, the backward Euler difference for time discretization is not necessary. Thus, the stability and convergence problems caused by time discretization are avoided. A series of numerical test cases are discussed to examine the performance of the proposed model. The simulation workflow is validated through the comparison with discrete fracture model and embedded discrete fracture model in real space. It is demonstrated that the proposed Laplace-transform embedded discrete fracture model is accurate for single flow with complex SRV distribution. On the basis of the Laplace-transform embedded discrete fracture model, we provided three applications of the new method: (1) analysis of the SRV effect on fluid flow behavior, (2) pressure transient analysis considering reservoir heterogeneity, (3) production performance analysis with time-varying production rate.

The neuronally expressed developmentally downregulated 4 (NEDD4) gene encodes a ubiquitin ligase that targets the epithelial sodium channel for degradation and has been implicated in tumor growth in various cancers. Hence, in this study, we intended to characterize the functional relevance of the NEDD4-mediated Kruppel-like factor 8/microRNA-132/nuclear factor E2-related factor 2 (KLF8/miR-132/NRF2) axis in the development of bladder cancer. NEDD4 and KLF8 were overexpressed in bladder cancer tissues and were associated with poorer patient survival rates. In bladder cancer cells, NEDD4 intensified the stability and transcriptional activity of KLF8 through ubiquitination to augment cell viability and migratory ability. Our investigations revealed that NEDD4 promotes the binding of KLF8 to the miR-132 promoter region and inhibits the expression of miR-132. KLF8 inhibited the expression of miR-132 to augment the viability and migratory ability of bladder cancer cells. Furthermore, miR-132 downregulated the expression of NRF2 to restrict the viability and migratory ability of bladder cancer cells. In addition, in vivo findings verified that NEDD4 regulates the KLF8/miR-132/NRF2 axis by accelerating tumor growth and lung metastasis. In conclusion, this study highlights NEDD4 as a potential therapeutic target against tumor recurrence and metastasis in bladder cancer.

Fracture has significant effect on the production of hydrogen–carbon compound reservoirs. Underground fluid always flows through different spaces which involves different flow patterns. In this study, the embedded discrete fracture method (EDFM) to couple the flow in matrix and fracture is introduced. The Darcy flow is considered in fracture while the Pre-Darcy flow is employed in matrix. The model of two phase flow problem is established. The governing equations are coupled through multiple spatial scales. The structured mesh is applied to discrete the whole matrix domain. The fracture grids are embedded to the matrix meshes. The verification shows good accuracy of the fully implicit method for solving the model. Based on the numerical simulation, the results of 1D, 2D flow problems considering Pre-Darcy flow are presented. The characteristic of pressure and saturation is analyzed. Some numerical experiment examples are conducted to demonstrate the capability of the method including multiple wells system, complex fracture problem, and hydraulic fractured horizontal well system. Furthermore, we extend the model to 3D transport problem. The newly developed numerical simulation method improves the limitations of EDFM in Pre-Darcy flow. The newly developed simulation method can be taken as an effective tool for hydrocarbon production analysis when Pre-Darcy flow happens in fractured porous media.

Metamaterials can control incident waves in the sub-wavelength range through the design of artificial structures, and realize the functions that natural materials cannot achieve. The study of metamaterials has important theoretical value and application prospects. In recent years, the proposal of computational metamaterials has opened up a brand-new direction for analog computing, providing high-throughput, energy-free computing methods for special computing tasks. However, the development of acoustic computing metamaterials is relatively preliminary, and it is necessary to develop design theories. There is no work to solve partial differential equations and realize fractional Fourier transform in spatial domain acoustic computing metamaterials. In this paper, the acoustic wave computational metamaterial is designed, and the simulation realizes the spatial domain fractional Fourier transform and partial differential equation calculation. It is expected that acoustic computational metamaterials will enable new capabilities in signal acquisition and processing, network computing, and drive new applications of sound wave.

Potentilla anserina L polysaccharide (PAP) is known to regulate immunity. Poly(lactic-co-glycolicacid) (PLGA) is a type of drug carrier with biocompatibility and biodegradable USFDA approved polymer, which possesses the advantages of high safety and good sustained-release effect. The DEC205 receptor, a type I membrane protein, is widely distributed on the surface of macrophages and dendritic cells (DCs) and plays a key role in antigen recognition and presentation. In this study, we prepared Potentilla anserina L polysaccharide PLGA nanoparticles targeting DEC205 receptor (DEC205-PAPP) and characterized the nanoparticles with regards to their effects on immune activation in vitro and in vivo. In vitro, DEC205-PAPP promoted the uptake activity of macrophages and increased the secretion of NO and cytokines (IFN-γ, IL-4, IL-6, and GM-CSF), up-regulated the expression of CD80

The development of multifunctional and robust swimming microrobots working at the free air-liquid interface has encountered challenge as new manipulation strategy are needed to overcome the complicated interfacial restrictions. Here, we show flexible but reliable mechanisms to achieve a remote-control bubble microrobot with multiple working modes and high maneuverability by the assistance of a soft air-liquid interface. This bubble microrobot is developed from a hollow Janus microsphere regulated by a magnetic field, which can implement switchable working modes like pusher, gripper, anchor and sweeper. The cavitation of the microbubble and the accompanying directional jet flow play a key role for functioning in these working modes, which is analogues to "bubble tentacle". In particular, we find a novel speed modulation method for the bubble microrobot that does not need to change the fuel concentration. Our findings demonstrate a substantial advance of the bubble microrobot specifically working at the air-liquid interface. And the results depict the nonintuitive mechanisms, such as bubble dynamics confined by a free surface, hydrodynamic jetting and surface capillary wave induced by bubble collapse, and bubble particle interaction, which offer helpful insights for developing swimming microrobots working in complicated environments.