三菱集团（Mitsubishi Group）是由原先日本三菱财阀解体后的公司共同组成的一个松散的实体，Mitsubishi这个名字中的mitsu表示“三”，而bishi表示“菱角”。三菱集团已经有100多年的历史，特别是在明治维新以后，三菱集团才开始步入了真正意义上的发展。接着三菱开始涉足采矿、造船、银行、保险、仓储和贸易，随后又经营纸、钢铁、玻璃、电气设备、飞机、石油和房地产等行业。发展至今，三菱已建立起一系列的企业，在日本工业现代化的过程中扮演着举足轻重的角色。
Ventilator-associated events (VAEs), developed by the US Centers for Disease Control and Prevention (CDC), are considered a new medical quality indicator associated with poor outcomes. However, previous studies failed to adjust for changes in patient severity, leaving open the possibility that VAEs are just a surrogate for severity. This study aimed to reevaluate the association between VAEs and mortality, adjusting for changes in severity over time. This multicenter observational study was conducted in 18 ICUs in Japan between May 2020 and December 2022. Patients aged ≥ 12 years who received mechanical ventilation for ≥ 3 consecutive days were eligible. VAE was diagnosed according to the CDC definition. The primary outcome was 30-day in-hospital mortality, whose association with VAE was estimated by the inverse probability weighted proportional hazards model, with temporal changes in patient severity treated as time-dependent confounders. Among 1,094 subjects, 106 VAEs (9.7
It is well-known that Ni alloy 600 exhibits lower susceptibility to SCC than stainless steel 304 in chloride-containing environments. To understand potentially relevant electrochemical differences, the kinetics of localized dissolution and the repassivation behavior of the two alloys were compared under pit/crack-like environments. Downward potential scans were conducted at isothermal conditions on 1D pit samples to assess the kinetics of metal dissolution. Downward temperature scans under potentiostatic conditions were performed to determine the conditions of potential, temperature and pit depth at which each alloy repassivates. Alloy 600 exhibits slower activation-controlled dissolution kinetics than SS304 in pit/crack-like environments. However, Ni600 stays active at conditions of lower aggressiveness, like lower temperature, whereas SS304 exhibits a higher tendency to repassivate. DFT calculations help explain these conflicting results and develop an understanding of the behavior of these different materials under SCC conditions.
Bài viết giới thiệu giải pháp ứng dụng công nghệ làm lạnh ngưng tụ nhiệt độ thấp sử dụng turbine giãn nở (turbo expander - TE) kết hợp van Joule-Thomson (JT) tại Nhà máy Xử lý khí Dinh Cố. Đây là công nghệ làm lạnh ngưng tụ nhiệt độ thấp tiên tiến, hiện đại trên thế giới giúp gia tăng thu hồi sản phẩm lỏng từ nguồn khí đồng hành giàu cấu tử nặng mang lại giá trị kinh tế cao, giảm nhập khẩu và đáp ứng nhu cầu LPG trong nước, góp phần hình thành và phát triển thị trường khí khu vực Đông Nam Bộ và cả nước.Việc triển khai tại Nhà máy Xử lý khí Dinh Cố cho thấy hệ thống TE-JT kết hợp đạt được hiệu suất làm lạnh khí sâu hơn so với cấu hình chỉ sử dụng van JT. Nhờ đó, hiệu suất thu hồi propane (C3) luôn vượt quá 85%, góp phần cải thiện hiệu suất kinh tế của nhà máy. Giải pháp lai TE-JT không chỉ chứng tỏ tính ứng dụng cao trong bối cảnh thị trường năng lượng và LPG biến động mà còn là một bước tiến đáng kể trong việc hiện đại hóa công nghệ xử lý khí của Việt Nam, phù hợp với xu hướng toàn cầu về nâng cao hiệu quả năng lượng và giảm phát thải.
This paper describes both the mechanism of contact erosion under multiple switching and a method that estimates the contact erosion transition in low‐voltage switches. The contact height is decreased due to the contact erosion in multiple switching, and this reduces the overtravel. The contact force is decreased by 31% and the opening velocity is decreased by 55% due to a 1 mm reduction of overtravel in the testing switch. This situation increases the bounce time in the making (closing) operation and leads to an increase arc current ( I arc ) and arc duration (Δ t ) at make. On the other hand, the situation has almost no effect on the interruption characteristics. We clarified that I arc n Δ t at the make is increased, and the contact erosion is accelerated. Based on this mechanism, we constructed a model that calculates I arc n Δ t every switching. Finally, we proved that the transition of the contact erosion in multiple switching can be estimated using the model. © 2025 Institute of Electrical Engineers of Japan and Wiley Periodicals LLC.
