Complex section products have significant lightweight and functional characteristics, and the twin-roll casting (TRC) is characterized by high efficiency and short flow. Hence, the TRC process for ...fabricating complex section products combines both advantages and will have a broader market demand and application prospect. In this paper, the research progress in recent years is reviewed, and novel TRC processes are divided into three categories according to the product section characteristics, namely transverse variable profiled strip, longitudinal variable profiled strip, and circular section products. The essence of the TRC process of complex section products is to change the steady-state characteristics in time series and the uniform characteristics in spatial distribution into transient or nonuniform. The technical principle, deformation characteristics, influence mechanism, are systematically analyzed. The current challenges and future directions of the TRC process are discussed.
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•A thermal-flow coupled model of the TRC for fabricating bimetallic clad strips is built.•The influence of the substrate strip on the heat transfer is analyzed.•Thermal resistance ...network at steady state is obtained.•The asymmetric heat transfer mechanism of the TRC is discussed.•The interface temperature evolution is derived from a thermocouple.
A numerical simulation method was adopted to study the asymmetric heat transfer characteristics of the twin-roll casting (TRC) process for fabricating bimetallic clad strips. A 2-D thermal-flow coupled model, consisting of molten pool, substrate strip and casting rolls, was established based on the Fluent software. The TRC process of fabricating Ti/Al and Cu/Al clad strips was analyzed. The influence of the substrate strip material properties, thickness and preheating temperature on the Kissing Point (KP) height, KP migration and temperature field of the casting rolls was determined. Then, the thermal resistance network was established, and the asymmetric heat transfer mechanism was discussed. Results indicate that, besides the process parameters, the influence of the substrate strip is significant. The effect of the process parameters, such as cast-rolling velocity and casting temperature, are mainly to change the heat input of the molten pool. Similarly, the effect of the preheating temperature is mainly to change the heat input of the substrate strip. However, the effects of the substrate strip material properties and thickness are mainly to change the total thermal resistance from the molten pool to the casting roll that contacts to the substrate strip, which is the main cause of the asymmetric heat transfer.
•A solid-liquid cast-rolling bonding process was developed to fabricate bimetallic clad pipes.•A 3-D thermal-flow coupling simulation model was established to predict the process window.•Steel/Al ...clad pipes, Cu/Al clad pipes, Ti/Al clad pipes, Cu/Al clad bars were fabricated successfully.
The solid-liquid cast-rolling bonding (SLCRB) process to fabricate bimetallic clad pipes was developed, and the numerical analysis was conducted in order to reduce the exploration time of reasonable technological parameters. A 3-D steady state thermal-flow coupling simulation model of the cast-rolling area was established based on the Fluent software. The distributions of the flow field and temperature field were obtained, and the influences of molten pool height, cast-rolling speed and casting temperature on the kiss point (KP) were analyzed systematically. It indicates that the forming mechanism of the SLCRB process is mainly ascribed to the fluidity of the molten metal in the liquid zone and the plastic deformation behavior in the semisolid and solid zone. Therefore, the prediction models of the average KP height and average export temperature were established and then used to predict the available process window. Under the guidance of the theoretical analysis, the SLCRB experiments were carried out and results agree well with the simulation results. Steel/Al clad pipes, Cu/Al clad pipes, Ti/Al clad pipes, Cu/Al clad bars were fabricated successfully, which indicates that the SLCRB process provides an efficient way to fabricate bimetallic clad pipes with desired bonding effect.
A new twin-roll casting (TRC) process to produce Cu/Invar/Cu clad strips, which have greater application potential, is proposed. The symmetrical cast-rolling zone is divided into two asymmetrical ...parts by introducing the substrate strip in the middle. The thermal-flow coupled simulation was conducted, and it realized the coupling analysis of casting roll, molten pool, and substrate strip. The results indicate that the kissing point (KP) shape in each part is asymmetric and vortexes are more likely to occur near the KP. Besides, univariate analyses show that the influence of the cast-rolling velocity, substrate preheat temperature and casting temperature on the KP length and average outlet temperature is linear, and the influence of the substrate thickness is nonlinear. Process window prediction models were obtained, which laid the foundation of setting process parameter combinations for providing the required KP length. Furthermore, numerical simulation results indicate that the fluidity of the liquid metal ensures the continuity of production. The macro-structures evolution in the cast-rolling zone indicates that deformation below the KP ensures the quality of the product. Finally, the Cu/Invar/Cu clad strips with metallurgical bonding were fabricated. The ultimate tensile strength and maximum peeling strength are 250 MPa and 126.5 N/mm, respectively. Hence, the TRC process for trimetallic clad strips is developed successfully and stability is basically achieved through equipment design, process window prediction, experimental validation, and bonding strength characterization. These methods can be conducive to the development of other new TRC processes for multiply clad strips.
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The observation of solid earth tides (SET) provides an important basis for understanding the structure of the earth’s interior, and has long been the focus of research in geoscience. However, ...actually, there still exist some limitations in capturing its global-scale information only with ground stations. Remote sensing technology can realize large-scale deformation monitoring of high point density constantly. However, it is still difficult for the artificial satellite system to meet the requirements of SET monitoring in terms of field of view and temporal resolution now. In this work, the moon is hypothesized as a new platform for SET observation combined with interferometric synthetic aperture radar (InSAR) technology. Based on the tidal model and lunar ephemeris, the spatial and temporal characteristics of the SET from the lunar view were analyzed. Furthermore, the calculations demonstrate that more abundant SET information can be observed in this view. After comparing various observation modes, the single-station with repeat-pass differential InSAR was selected for this simulation. We mainly considered the restriction of observation geometry on moon-based InSAR under three signal bandwidths, thereby providing a reference for the sensor design. The results demonstrate that the moon-based platform offers the potential to become an optimal SET observation method.
Tumors have evolved in various mechanisms to evade the immune system, hindering the antitumor immune response and facilitating tumor progression. Immunotherapy has become a potential treatment ...strategy specific to different cancer types by utilizing multifarious molecular mechanisms to enhance the immune response against tumors. Among these mechanisms, the ubiquitin-proteasome system (UPS) is a significant non-lysosomal pathway specific to protein degradation, regulated by deubiquitinating enzymes (DUBs) that counterbalance ubiquitin signaling. Ubiquitin-specific proteases (USPs), the largest DUB family with the strongest variety, play critical roles in modulating immune cell function, regulating immune response, and participating in antigen processing and presentation during tumor progression. According to recent studies, the expressions of some USP family members in tumor cells are involved in tumor immune escape and immune microenvironment. This review explores the potential of targeting USPs as a new approach for cancer immunotherapy, highlighting recent basic and preclinical studies investigating the applications of USP inhibitors. By providing insights into the structure and function of USPs in cancer immunity, this review aims at assisting in developing new therapeutic approaches for enhancing the immunotherapy efficacy. Keywords: Ubiquitin-specific proteases (USPs), Cancer, Immunotherapy, USP inhibitors
In view of the problems of traditional repair materials for anchorage concrete of expansion joints, such as ease of damage and long maintenance cycles, the design of polyurethane concrete was ...optimized in this article, which could be used for rapid repair of concrete in anchorage zone of expansion joints. A new type of carbon fiber grid–polyurethane concrete system was designed, which makes the carbon fiber grid have an excellent synergistic effect with the quick-hardening and high-strength polyurethane concrete, and improved the flexural bearing capacity of the polyurethane concrete. Through the four-point bending test, the influence of the parameters such as the number of grid layers, grid width, and grid density on the flexural bearing capacity of polyurethane concrete beams was tested. The optimum preparation process parameters of carbon fiber grid were obtained to improve the flexural performance of polyurethane concrete. Compared with the Normal specimen, C-80-1’s average flexural strength increased by 47.7%, the failure strain along the beam height increased by 431.1%, and the failure strain at the bottom of the beam increased by 68.9%. The best width of the carbon fiber grid was 80 mm, and the best number of reinforcement layers was one layer. The test results show that the carbon fiber grid could improve the flexural bearing capacity of polyurethane concrete. The carbon fiber grid–polyurethane concrete system provides a new idea for rapid repair of the anchorage zone of bridge expansion joints, and solves the problems such as ease of damage and long maintenance cycles of traditional repair materials, which can be widely used in the future.
Tumor metastasis remains the main cause of breast cancer-related deaths, especially delayed breast cancer distant metastasis. The current study assessed the frequency of CD44
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/CD24
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breast cancer ...cells in 576 tissue specimens for associations with clinicopathological features and metastasis and investigated the underlying molecular mechanisms. The results indicated that higher frequency (≥19.5%) of CD44
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/CD24
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cells was associated with delayed postoperative breast cancer metastasis. Furthermore, CD44
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/CD24
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triple negative breast cancer (TNBC) cells spontaneously converted into CD44
+
/CD24
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cancer stem cells (CSCs) with properties similar to CD44
+
/CD24
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CSCs from primary human breast cancer cells and parental TNBC cells in terms of stemness marker expression, self-renewal, differentiation, tumorigenicity, and lung metastasis in vitro and
in NOD/SCID mice
. RNA sequencing identified several differentially expressed genes (DEGs) in newly converted CSCs and
RHBDL2
, one of the DEGs, expression was upregulated. More importantly,
RHBDL2
silencing inhibited the YAP1/USP31/NF-κB signaling and attenuated spontaneous CD44
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/CD24
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cell conversion into CSCs and their mammosphere formation. These findings suggest that the frequency of CD44
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/CD24
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tumor cells and
RHBDL2
may be valuable for prognosis of delayed breast cancer metastasis, particularly for TNBC.
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•A solid-liquid cast-rolling bonding (SLCRB) process was proposed to fabricate bimetallic clad pipes based on twin-roll casting and pass rolling.•The deformation is along the rolling ...direction (RD), along with the metal flow from normal direction (ND) side to transverse direction (TD) side.•The ideal and complete interface evolution process of the SLCRB process can be subdivided into four stages.
Using Cu pipes and molten Al as the substrate metal and cladding metal respectively, the bonding mechanism of the solid-liquid cast-rolling bonding (SLCRB) process to fabricate bimetallic clad pipes was investigated through the experiment and simulation. The interface evolution of the cast-rolling area was obtained using oxide as the tracer and a thermal-mechanical coupling model was established to obtain the temperature and pressure distribution. Results indicate that it is a progressive contact behavior of the bonding interface in the cast-rolling area. The deformation is mainly along the rolling direction (RD), along with the metal flow from the normal direction (ND) side to transverse direction (TD) side. The ideal and complete interface evolution process of the SLCRB process can be subdivided into four stages including eight sub-processes: solid-liquid contact heat-exchange stage, solid-semisolid cast-bonding stage, solid-solid hot roll-bonding stage, solid-solid diffusion welding stage. Therefore, the SLCRB process is the synthetic action combining the diffusion, reaction, mechanical interlocking, roll-bonding etc. More generally, the interface evolution in practice is closely related to the physicochemical properties of substrate/cladding materials and the interaction mechanical behavior under high temperature. And it is usually a reasonable combination of some of these sub-processes.
Single-layer reticulated shells are widely used as roof structures of gymnasiums. However, the seismic performance of the single-layer reticulated shell with a center-hung scoreboard (CHS), which is ...a kind of large-scale display device suspended on the roof center of many gymnasiums, has not been fully studied. In this paper, the influence of the CHS on the seismic response of single-layer reticulated shells is investigated. Single-layer reticulated shells and the CHS-integrated models including flexibly suspended models and simplified models are established, respectively, using the Abaqus software. The responses of integrated models are calculated by an explicit dynamic method under 3D seismic action. The axial forces of the flexibly suspended case and the simplified case where the scoreboard is simplified as fixed masses on the roof structure are compared. Compared with those in the simplified model, the axial forces of some shell members and some nodal acceleration in the flexibly suspended model under multiple seismic excitations would increase by as high as 125% and 315%, respectively. It turns out that seismic responses of the single-layer reticulated shell would be underestimated if a simplified model was used for seismic response analysis. The region near the boundary and the region neighbouring the support platform members are the most affected regions due to the combination of the horizontal swing effect and the vertical impact effect of the CHS under multiple seismic excitations.
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