Quasi In-Situ EBSD Analysis of Twinning-Detwinning and Slip Behaviors in Textured AZ31 Magnesium Alloy Subjected to Compressive-Tensile Loading

Twinning and detwinning behavior, together with slip behavior, are studied in a textured AZ31 magnesium alloy under compressive and tensile strains along the rolling direction (RD) after each interrupted mechanical test via quasi in-situ electron backscattered diffraction technique. The results show that twinning firstly takes place under the compressive strain along the RD. With the increasing compressive strain, {1012} tensile twins firstly nucleate, then propagate, and finally thicken. While under a reversed tensile strain along the RD, detwinning occurs. No nucleation happens during detwinning. Thus, tensile twins can detwin at lower tensile strain, followed by thinning, shortening, and vanishing. Slips are also activated to accommodate the plastic deformation. In the matrix, prismatic slip can only dominate at relatively high strains. Otherwise, basal slip dominates. While in the twins, prismatic slip can activate at lower strains, which is ascribed to the texture reorientation

INTERCONNECT STRUCTURE TO IMPROVE CHIP SIGNAL INTEGRITY AND MECHANICAL RELIABILITY

Techniques are presented herein that support a novel chip interconnect structure, encompassing convex- and concave-shaped copper joint pillars, for connecting a chip (that follows the Optical Internetworking Forum (OIF) next generation (NG) common electrical input/output (CEI)-224 gigabit per second (G) framework) to a printed circuit board (PCB). Aspects of the presented techniques provide excellent signal integrity (SI) performance (including return loss, insertion loss, and impedance discontinuity) in support of, for example, a 102.4 terabit (T) per second switch comprising, among other things, an application-specific integrated circuit (ASIC) having 512 lanes of 224G Serializer/Deserializer (SerDes) capacity. Under further aspects of the techniques, mechanical performance and long-term reliability are significantly improved

Distributions of surface sediments surrounding the Antarctic Peninsula and its environmental significance

We analyzed grain size composition to provide information on the types and distributions as well as depositional varieties of marine surface sediments from the area surrounding the Antarctic Peninsula. The samples retrieved from the study area contain gravel, sand, silt and clay. As suggested by bathymetry and morphology, the study area is characterized by neritic, hemipelagic and pelagic deposits. The glacial-marine sediments can be divided into two types, residual paratill and compound paratill, which are primarily transported by glaciers and as ice-rafted debris. Ocean current effects on deposition are more obvious, and the deposit types are distributed consistently with terrain variations

Electrochemically Induced Amorphous-to-Rock-Salt Phase Transformation in Niobium Oxide Electrode for Li-Ion Batteries

Intercalation-type metal oxides are promising negative electrode materials for safe rechargeable lithium-ion batteries due to the reduced risk of Li plating at low voltages. Nevertheless, their lower energy and power density along with cycling instability remain bottlenecks for their implementation, especially for fast-charging applications. Here, we report a nanostructured rock-salt Nb2O5 electrode formed through an amorphous-to-crystalline transformation during repeated electrochemical cycling with Li+. This electrode can reversibly cycle three lithiums per Nb2O5, corresponding to a capacity of 269 mAh g−1 at 20 mA g−1, and retains a capacity of 191 mAh g−1 at a high rate of 1 A g−1. It exhibits superb cycling stability with a capacity of 225 mAh g−1 at 200 mA g−1 for 400 cycles, and a Coulombic efficiency of 99.93%. We attribute the enhanced performance to the cubic rock-salt framework, which promotes low-energy migration paths. Our work suggests that inducing crystallization of amorphous nanomaterials through electrochemical cycling is a promising avenue for creating unconventional high-performance metal oxide electrode materials

Roles of Twinning and \u3c a \u3e Slipping in Tensile Anisotropy of Rolled Mg-3Al-Zn Alloy

In this work, the {101‾2} tensile twinning and \u3c a \u3e type slipping dependence of plastic anisotropy in the rolled Mg-3Al-Zn alloy are studied by using tensile tests along two orthogonal directions, the rolling direction and normal direction. The results show that the initial basal texture of the material influences the activities of twinning and slips, leading to anisotropic deformation. During tension along the rolling direction, the deformation is dominated by basal and prismatic \u3c a \u3e slips. During tension along the normal direction, the deformation is accommodated through tensile twinning and basal \u3c a \u3e slip; prismatic \u3c a \u3e slip is hard to active in matrix grains, but it plays an important role in twined regions

SHP-2 restricts apoptosis induced by chemotherapeutic agents via Parkin-dependent autophagy in cervical cancer

Abstract Background Autophagy is a cell degradation pathway that eliminates damaged or unwanted proteins and organelles. Autophagy protects cells from chemotherapeutic agents by scavenging damaged mitochondria. Methods Plasmid transfection and shRNA were used to regulate SHP-2 expression. Annexin V/PI staining were employed to analysis apoptosis. Flow cytometry was used to analyse intracellular calcium level and ROS. Immunofluorescence was used to detect mitochondria membrane potential, autophagy and Parkin translocation. Results In cervical cancer, we found that SHP-2 suppressed apoptosis induced by Oxaliplatin and 5-FU. Further studies have found that SHP-2 protects against mitochondrial damage. This role of SHP-2 is associated with the activation of autophagy. In addition, SHP-2 degraded impaired mitochondria dependent on the ubiquitin ligase function of Parkin. Conclusions These results suggest that SHP-2 inhibits the apoptosis induced by chemotherapeutic drugs through activating autophagy to degrade damaged mitochondria and ubiquitin ligase Parkin involved in SHP-2 induced autophagy

experimental study on parameter choices in norm-r support vector regression machines with noisy input

对商品实施网络营销的前提是进行商品数字化,而数字化产品和非数字化产品的数字化程度不同,因此两类商品的网络营销具有差异性。该文以软件和玉器为例从数字化程度、消费者心理、网络广告和网络营销策略等几个方面分析了两类商品网络营销的差异性

SlSPS, a Sucrose Phosphate Synthase Gene, Mediates Plant Growth and Thermotolerance in Tomato

Heat stress (HS) has been considered as a severe threat to crop yields in recent years. Sucrose, as a major product of photosynthesis, plays an important role in plant growth and stress response. Sucrose phosphate synthase (SPS) is a key rate-limiting enzyme in the sucrose synthesis pathway in plants. However, its molecular mechanism and signaling pathway remain unclear. In this study, we identified a novel SPS gene (SlSPS) in tomato and generated over-expression and knock-out of SlSPS gene transgenic tomato plants to investigate its biological functions related to the growth and thermotolerance of tomato. Over-expression of SlSPS gene increased the growth and biomass of transgenic tomato plants, such as fresh weight, dry weight, plant height, fruit weight and root length. In contrast, knock-out of SlSPS gene decreased the growth and biomass of transgenic tomato plants. Under heat stress, the survival rates were positively correlated with the expression level of SlSPS gene in different tomato varieties. Furthermore, SlSPS-overexpressing tomato plants showed higher SPS activity and sucrose content and heat stress resistant phenotypes. By comparison, knock-out tomato plants showed lower SPS activity and sucrose content and susceptible to heat stress. The determination of several reference values of oxidative stress parameters were also consistent with their heat resistance of these transgenic plants. In summary, SlSPS gene could positively mediate the growth and thermotolerance in tomato plants

Thermal Effect on Dislocation Interactions in Magnesium Alloy

In this work, dislocation interactions are directly observed and analyzed by using in-situ transmission electron microscope during heating processes in a pre-deformed Mg-3Al-1Zn magnesium alloy. Thermodynamic behaviors of two types of dislocations are investigated, i.e., individual dislocations and low-angle grain boundary arranged by dislocations. The results show that the low-angle grain boundary remains stable as the heating temperature increases to 673 K, while most of the individual dislocations disappear until the heating temperature reaches 473 K. Furthermore, the low-angle grain boundary tends to absorb individual dislocations nearby. The stability and the annihilation of both types of dislocations are discussed