Controllable Magnetic Proximity Effect and Charge Transfer in 2D Semiconductor and Double-Layered Perovskite Manganese Oxide van der Waals Heterostructure

Optically generated excitonic states (excitons and trions) in transition metal dichalcogenides are highly sensitive to the electronic and magnetic properties of the materials underneath. Modulation and control of the excitonic states in a novel van der Waals (vdW) heterostructure of monolayer MoSe₂ on double-layered perovskite Mn oxide ((La_0.8Nd_0.2)_1.2Sr_1.8Mn₂O₇) is demonstrated, wherein the Mn oxide transforms from a paramagnetic insulator to a ferromagnetic metal. A discontinuous change in the exciton photoluminescence intensity via dielectric screening is observed. Further, a relatively high trion intensity is discovered due to the charge transfer from metallic Mn oxide under the Curie temperature. Moreover, the vdW heterostructures with an ultrathin h-BN spacer layer demonstrate enhanced valley splitting and polarization of excitonic states due to the proximity effect of the ferromagnetic spins of Mn oxide. The controllable h-BN thickness in vdW heterostructures reveals a several-nanometer-long scale of charge transfer as well as a magnetic proximity effect. The vdW heterostructure allows modulation and control of the excitonic states via dielectric screening, charge carriers, and magnetic spins.     

Remote laser welding applications for car bodies

The fundamental objective of this study is to ensure the safety of nuclear reactors. A few accidents involving leaks from welded zones at the pipe penetration part of reactor vessels or at coolant pipes have been reported at home and abroad. One of the main causes is welding residual stress. Therefore, it is very important to know the welding residual stress in order to maintain the high safety of the plant, estimate the plant life cycle and design an effective maintenance plan. Welded joints of nuclear reactor vessels have complex shapes, and the welding residual stresses also have three-dimensional (3D) complex distributions. In this study, inherent strain-based theory and method are applied to measure the welding residual stresses. The inherent strain method is an analytical method as an inverse problem, using the least squares method, based on the finite element method. So the method gives the most probable value and deviation of residual stress. The reliability of the estimated result is discussed. In this method, inherent strains are unknowns. When residual stresses are distributed complexly in a 3D stress-state, the number of unknowns becomes very large. So, the inherent strain distribution is expressed with an appropriate function to decrease largely the number. A mock-up is idealized for a welded joint at the pipe penetration part of an actual reactor vessel. The inherent strain method is applied to the measure the residual stress of the joint. In this paper, the applicability of the inherent strain distribution function is diagnosed. Ten kinds of functions are applied to estimate the residual stress, and the accuracy and reliability of the analysed results are judged from three points of view, i.e. residuals, unbiased estimate of variance of errors and welding mechanics. The most suitable function is selected, which brings the most reliable result.     

In Situ PD-L1 Expression in Oral Squamous Cell Carcinoma Is Induced by Heterogeneous Mechanisms among Patients

The expression of programmed death ligand-1 (PD-L1) is controlled by complex mechanisms. The elucidation of the molecular mechanisms of PD-L1 expression is important for the exploration of new insights into PD-1 blockade therapy. Detailed mechanisms of the in situ expression of PD-L1 in tissues of oral squamous cell carcinomas (OSCCs) have not yet been clarified. We examined the mechanisms of PD-L1 expression focusing on the phosphorylation of downstream molecules of epidermal growth factor (EGF) and interferon gamma (IFN-γ) signaling in vitro and in vivo by immunoblotting and multi-fluorescence immunohistochemistry (MF-IHC), respectively. The in vitro experiments demonstrated that PD-L1 expression in OSCC cell lines is upregulated by EGF via the EGF receptor (EGFR)/PI3K/AKT pathway, the EGFR/STAT1 pathway, and the EGFR/MEK/ERK pathway, and by IFN-γ via the JAK2/STAT1 pathway. MF-IHC demonstrated that STAT1 and EGFR phosphorylation was frequently shown in PD-L1-positive cases and STAT1 phosphorylation was correlated with lymphocyte infiltration and EGFR phosphorylation. Moreover, the phosphorylation pattern of the related molecules in PD-L1-positive cells differed among the cases investigated. These findings indicate that PD-L1 expression mechanisms differ depending on the tissue environment and suggest that the examination of the tissue environment and molecular alterations of cancer cells affecting PD-L1 expression make it necessary for each patient to choose the appropriate combination drugs for PD-1 blockade cancer treatment.     

陶瓷膜处理聚醚废水通量影响因素的试验研究

利用陶瓷膜技术处理高浓度聚醚废水回收大分子聚醚多元醇.研究了浓缩倍数、温度、跨膜压差(TMP)等因素对渗透通量的影响.通过对试验数据的统计学分析,确定TMP为0.20MPa、系统温度控制在43℃,此时CODCr的去除率＞95%,达到了设计要求.并对膜清洗工序进行了改进,提出了NaOH/EDTA复合清洗法,缩短了清洗时间.     

Recent Progress on Light‐Emitting Electrochemical Cells with Nonpolymeric Materials

Light‐emitting electrochemical cells (LECs) have emerged as some of the simplest light‐emitting devices. Indeed, numerous LECs have been produced using fluorescent polymers; however, initial LEC structures require a mixture of polymers and electrolytes, thus strictly limiting their applicability. In contrast, recent advances in device technologies and material synthesis have opened a route for LECs using nonpolymeric materials. This progress report focuses on current developments in the device concepts, mechanisms, and characteristics of LECs that allow the utilization of nonpolymeric materials. First, the three primary device types, namely, electrochemically doped, ionic‐material, and electrostatically doped LECs, are categorized, and their distinct features are described. Second, electrochemically doped LECs based on small molecules and branched molecules are introduced. Then, an overview of the rapidly growing field of ionic‐material LECs, especially ionic transition metal complexes, ionic small molecules and perovskites, and their characteristics are provided. Following these results, recent achievements in solid‐state materials, such as inorganic single crystals, quantum dots, and 2D materials, as electrostatically doped LECs are highlighted. Finally, an overview and evaluation of these LECs reveal the key directions and remaining issues that must be overcome to further functionalize LECs, which provide a versatile approach for new lighting applications comprising emergent materials.     

Drying and rehydration of pasta

Pasta is dried at the production stage and consumed after rehydration by cooking. Because the water migration behavior during drying and rehydration largely affects the quality of pasta, a better understanding of this behavior helps to efficiently manufacture and cook pasta of good quality. However, the key mechanism controlling water migration inside pasta is not fully understood. This review aims to provide an overview of the phenomena occurring during the drying and rehydration processes. In addition, the effects of drying and rehydration conditions on pasta quality are discussed. Knowledge of these effects would be useful for rational determination of the conditions for producing pasta with desired qualities.     

Lipid Bilayers on a Picoliter Microdroplet Array for Rapid Fluorescence Detection of Membrane Transport

This paper describes picoliter‐sized lipid bilayer chambers and their theoretical model for the rapid detection of membrane transport. To prepare the chambers, semispherical aqueous droplets are patterned on a hydrophilic/hydrophobic substrate and then brought into contact with another aqueous droplet in lipid‐dispersed organic solvent, resulting in the formation of the lipid bilayers on the semispherical droplets. The proposed method implements the lipid bilayer chambers with 25‐fold higher ratio of lipid membrane area (S) to chamber volume (V) compared to the previous spherical droplet chambers. Using these chambers, we are able to trace the time‐course of Ca²⁺ influx through α‐hemolysin pores by a fluorescent indicator. Moreover, we confirm that the detection time of the substrate transport is inversely proportional to the S/V ratio of the developed chambers, which is consistent with the simulation results based on the developed model. Our chambers and model might be useful for rapid functional analyses of membrane transport phenomena.     

大钢模板在地下室外墙中应用的技术分析

目前,大型公建项目的地下室外墙模板主要采用木模板及小钢模进行支设,但两者都有各自的优缺点.以京东方运营与研发中心工程为例,根据其特点,对木模板、小钢模板和大钢模板进行了对比分析,并着重介绍了地下室外墙模板采用了大钢模板的设计与方法,希望为后续类似工程地下室外墙模板的施工起到借鉴的作用.     

C60 thin-film transistors with high field-effect mobility,fabricated by molecular beam deposition

We report performance of C₆₀ thin-film field-effect transistors and characterizations of C₆₀ thin-films on SiO₂ substrates fabricated by molecular beam deposition. Devices, fabricated and characterized under high vacuum without exposing to air, routinely showed current on/off ratios >10⁸ and field-effect mobility in the range of 0.5–0.3 cm²/V s. The obtained mobility is comparable to the highest value among n-type organic thin-film transistors and close to that derived from the photocurrent measurements on C₆₀ thin-films.The grain size of C₆₀ thin-film, condensed in an fcc solid, increases with the substrate temperature, while themobility did not exhibit a clear relation with substrate temperature.

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