Response of the northwestern Pacific upper water δ~(13)C to the last deglacial ventilation of the deep Southern Ocean

The deglacial δ~13C minimum events that originated from the ventilation of the deep Southern Ocean around Antarctica, have been recorded in a range of marine sediments from the southern to tropical oceans in late Pleistocene. However, the broad δ~13C minimum event was also reported as far as to the northern middle latitudes, in northwestern Pacific marginal sea areas, during the last deglaciation. In the northwestern Pacific, forcing from the northern high latitudes is strongly expressed, while the records of in- fluence from the southern high latitudes are few. The Kuroshio Source Region (KSR) forms a boundary between the northwestern Pacific and the southern, tropical Pacific. So, high-resolution planktonic foraminiferal records in core MD06-3054 from the KSR are well positioned to identify signals from the southern hemisphere in the northwestern Pacific. Planktonic foraminiferal tests from the upper 1030 cm of the core were subject to AMS14C, carbon and oxygen isotopic measurements. A negative excursion was found to occur from about 20.0-6.0 ka BP in δ~13C records of both surface (Globigerinoides ruber) and subsurface (Pulleni- atina obliquiloculata) dwellers, but the overall trends of the two curves have reversed since 26.5 ka BP. Moreover, the δ~13C rec- ord of G. ruber (the surface dweller) shows a robust link to the record of atmospheric CO2, and its changes precede the records of P. obliquiloculata (the subsurface dweller). According to the hydrologic conditions, the broad δ~13C minimum event recorded in the KSR is also a response to the increasing ventilation of the deep Southern Ocean around Antarctica during the last deglaciation. The inconsistency between the records of the surface and subsurface dwellers was possibly caused by the ways that the low δ~13C signal was transmitted. Subsurface water primarily received the low δ~13C signal from the Antarctic Intermediate Water (AAIW), whereas the surface water was probably mainly impacted by atmospheric CO2 in the KSR. The records from the KSR confirm the deduction that the broad δ~13C minimum event in the Okinawa Trough was due to the impact of tropical Pacific surface water dur- ing the last deglaciation, and suggest that signals from the southern high latitudes also can be delivered to the northern middle latitudes.     

无创机械通气技术探讨

经口/鼻面罩行无创正压通气（NIPPV）用于治疗急慢性呼吸衰竭已有十余年,NIPPV操作简单,易掌握,可减少急性呼吸衰竟患者的插管率,降低住院费用,正确掌握使用指征和操作是应用NIPPV应用成功的两大基础.探讨了无创机械通气与有创机械通气技术比较,无创呼吸机特点,临床应用指征及规范操作.     

采空区埋管抽放技术在U型通风系统工作面上隅角瓦斯治理应用研究

本文以山西晋煤集团岳城矿1302(下)综采工作面为例,探讨了U型通风系统工作面采空区瓦斯涌出规律及其治理原则,研究结果表明,通过在回风巷敷设两趟采空区管路,一趟插入上隅角进行抽放,另一趟埋入采空区进行埋管抽放,通过进行两趟管路抽放,可有效地遏制采空区瓦斯涌出,消除工作面上隅角瓦斯积聚现象,确保工作面安全生产。     

姚桥煤矿西翼通风系统优化改造研究

针对姚桥矿西翼通风系统存在的通风网络不健全、采区通风困难、矿井漏风量大等问题,对矿井通风系统模拟解算分析后,提出了矿井通风系统优化改造方案。优化后新系统在技术上的有效性、经济上的合理性、安全上的可靠性以及通风系统总的技术、经济效果都得到了大幅度提高,满足了西风井新主通风机联网运行的条件。     

地下金库通风除湿系统设计

地下金库通风除湿的主要任务是保证金库内存放物品的安全和对温湿度的要求。通过地下建筑的特点以及地下金库的湿源的分析,文章介绍了地下金库的通风除湿系统设计,着重讨论了冷冻除湿过程,通风方式以及通风口的设计。     

影响气体冷却服热舒适性因素的实验

采用真人实验的方法,研究人上体躯干穿着气体冷却服时衣内微空间气候参数及上体躯干皮肤温度受环境温度、劳动强度和通气量变化的影响。结果表明:环境温度是影响衣内空间空气温度、湿度及皮肤温度的最主要因素; 体表及衣内空间汗液蒸发吸热是影响衣内空间空气温度、湿度及皮肤温度的重要因素; 影响体表汗液蒸发的主要因素是体表气流速度、劳动强度及通入压缩空气水蒸气分压力; 增大压缩空气通气量对衣内空间空气温度、湿度及皮肤温度无显著影响。实验证明,该型气冷服能将人体皮肤温度控制在舒适范围内,对人体热舒适性具有一定程度的改善作用,但气冷服结构、压缩空气管及开孔布局有待改进,以充分利用汗液蒸发吸热作用,提高气冷服的降温效果。     

屏障动物房书虱爆发、处置与风险评估

书虱属啮虫目虱科昆虫,是粮仓、图书馆及家居生活中较常见的一类昆虫,较少出现在实验动物屏障环境中。本单位在屏障动物房IVC排风管道中发现书虱爆发,经采取管道清洗、敌敌畏消杀及降低湿度等措施,控制了书虱爆发,清除了病原威胁。本文对书虱爆发的经过、处置方法及效果进行了介绍,并对书虱的来源、处置方法的选择及书虱对实验动物屏障设施的潜在风险进行了探讨。     

湿热地区冷巷空间形态尺度量化模拟

为厘清中国南方传统民居中冷巷空间应对湿热气候蕴含的微气候调节作用,采用流体力学(CFD)模拟的方法,选择Autodesk CFD作为主要模拟实验分析工具,以热湿环境评价等级指标作为评价依据,将4类建筑空间,在冷巷不同空间形态尺度下形成的4种不同实验模型,分析工作面上的风速、空气温度、热舒适度及分布情况。结果表明,室外冷巷空间与室内空间相比,具有更高的热舒适度; 湿热地区中重要的经常性使用的建筑空间,应布置在南侧,夏季最大风频的上风向,次要的辅助性建筑空间宜布置在北侧,夏季最大风频的下风向; 进行建筑设计时,可以通过调整冷巷的偏转角度、宽度和形态,以达到改善建筑热环境的目的; 位于最大风频的下风向的后厅空间,要改善其热工环境,可以采用增大南北对流的开窗面积、增加门窗遮阳的策略。研究结果对于湿热地区现代建筑设计中建筑空间布局方式和冷巷空间形态尺度的应用实践具有一定价值。     

翼型捕风器在地下空间通风中的应用研究

以S1210型翼型为基础,设计了一种基于科恩达效应的捕风器,采用数值模拟的方法,在自然风速为3 m/s的情况下,对一尺寸为30 m×20 m×3.5 m的地下仓库实际通风效果进行了研究。研究结果表明:在不同捕风器高度下,室内通风换气次数均在1次以上,且随着捕风器高度提升,风管进出口的速度值不断增大、负压值不断减小,进出口压力差最大为1.3 Pa;翼型壁面上形成的负压区最下负压值为－14 Pa,随着捕风器高度的提升,通风量也随之增大,但由于同时增大了圆管内的摩擦阻力,通风量的增长速率不断减小;增加捕风器高度对增大通风量有作用且随高度增加作用不断减小;自然风速为1 m/s~5 m/s的工况下,当自然风速大于等于3 m/s时,采用两个翼型捕风器的地下空间通风换气次数可达到1.5次/h以上。