标准号: LY/T 3238-2020

摘要： 本文件规定了以汽油机为动力的可移动手扶式挖坑施肥机(以下简称“挖坑施肥机，’)的术语和定义、型号编制、技术参数、技术要求及试验方法、标志、使用说明书、包装、运输与贮存。本文件适用于在山地、丘陵地区对果树进行挖坑施肥的带支架的可移动手扶式挖坑施肥机。

标准号: LY/T 3237-2020

摘要： 本文件适用于在林区采伐、管养以及市政、园林绿化等场地内使用，以往复活塞式内燃机为动力并在位置固定时工作，通过具有水平或近似水平底板的进料槽装载包含主干的木、竹枝丫后自动进料，并且在距离碎化装置或独立进料装置的相应安全距离下的进料口尺寸大于400 mm X 400 mm的带有半挂式底盘的枝丫切碎机。

标准号: LY/T 3240-2020

摘要： 本文件规定了以锂离子电池为动力源，操作者通过操纵杆或方向盘操控行驶方向的坐骑式草坪修剪机(以下简称“坐骑式草坪机")的术语和定义、型号编制方法、基本参数、技术要求及试验方法、标志、使用说明书、包装、运输、贮存和处理。本文件适用于以标称电压不大于直流75 V可充电式锂离子电池组或电池包供电的坐骑式滚刀草坪机和坐骑式旋刀草坪机。

标准号: LY/T 3239-2020

摘要： 本文件适用于在自然环境条件下，以标称电压不大于75 V，可充电式铿离子电池包或电池组供电的由单人手持操作的对庭院花草等类似植物生长的土壤进行翻松作业的松土机。

标准号: LY/T 1202-2020

摘要： 本文件规定了以汽油机为动力的步进式草坪修剪机(以下简称“草坪机”)的术语和定义、型号编制方法、技术要求及试验方法、标志、使用说明书、包装、运输和贮存。本文件适用于以汽油机为动力的旋刀步进式草坪机和滚刀步进式草坪机，包括配备载有坐姿操作者乘人附件的步进式草坪机，并配备有:—金属切割装置，和/或;—非金属切割装置由一个或多个切割部件铰接安装在一个近似圆形的驱动装置上，切割部件依靠离心力来实现切割，且每个切割部件的切割能量(动能)不小于10)。

关键词： 热能动力机械   环境污染   发展分析  

摘要： 在日常生产中,锅炉被视为重点设备,它是提供热能的源泉。提高锅炉原有的运行效果、提高内部结构的燃烧速率、减少多重排放等都具有重要的意义。文章探讨与电力工程有关的问题。依托这种工程,促动锅炉固有的构架改进,满足长时段的环保需求。

关键词： 环境问题   热能动力机械   环境污染  

摘要： 热能机械是指将热能转化为可用动能的机械设备,它在各行业有着广泛的应用。热能机械在工作过程中会产生空气污染、废水和固体污染,对周围生态环境产生影响。故此,文章将分析热能动力机械构造,论证其环境影响,并从多个角度分析如何解决动力机械环境污染问题,旨在促进我国热能动力机械科学、环保发展。

关键词： hydrogen sensor   palladium   nanograting   nanotransducer   self-powered sensor  

摘要： This study proposes a reliable and self-powered hydrogen (H-2) gas sensor composed of a chemo-mechanically operating nanostructured film and photovoltaic cell. Specifically, the nanostructured film has a configuration in which an asymmetrically coated palladium (Pd) film is coated on a periodic polyurethane acrylate (PUA) nanograting. The asymmetric Pd nanostructures, optimized by a finite element method simulation, swell upon reacting with H-2 and thereby bend the PUA nanograting, changing the amount of transmitted light and the current output of the photovoltaic cell. Since the degree of warping is determined by the concentration of H-2 gas, a wide concentration range of H-2 (0.1-4.0%) can be detected by measuring the self-generated electrical current of the photovoltaic cell without external power. The normalized output current changes are similar to 1.5%, similar to 2.8%, similar to 3.5%, similar to 21.5%, and 25.3% when the concentrations of H-2 gas are 0.1%, 0.5%, 1.0%, 1.6%, 2%, and 4%, respectively. Moreover, because Pd is highly chemically reactive to H-2 and also because there is no electrical current applied through Pd, the proposed sensor can avoid device failure due to the breakage of the Pd sensing material, resulting in high reliability, and can show high selectivity against various gases such as carbon monoxide, hydrogen sulfide, nitrogen dioxide, and water vapor. Finally, using only ambient visible light, the sensor was modularized to produce an alarm in the presence of H-2 gas, verifying a potential always-on H-2 gas monitoring application.

关键词： Microfluidics  

摘要： Cell mechanical properties are powerful biomarkers for label-free phenotyping. To date, microfluidic approaches assay mechanical properties by measuring changes in cellular shape, applying extensional or shear flows or forcing cells to pass through constrictions. In general, such approaches use high-speed imaging or transit time measurements to evaluate cell deformation, while cell dynamics in-flow after stress imposition have not yet been considered. Here, we present a microfluidic approach to apply, over a wide range, tuneable compressive forces on suspended cells, which result in well distinct signatures of deformation-dependent dynamic motions. By properly conceiving microfluidic chip geometry and rheological fluid properties, we modulate applied single-cell forces, which result in different motion regimes (rolling, tumbling or tank-treating) depending on the investigated cell line. We decided to prove our approach by testing breast cell lines, with well-known mechanical properties. We measured a set of in-flow parameters (orientation angle, aspect ratio, cell deformation and cell diameter) as a backward analysis of cell mechanical response. By such an approach, we report that the highly invasive tumour cells (MDA-MB-231) are much more deformable (6-times higher) than healthy (MCF-10A) and low invasive ones (MCF-7). Thus, we demonstrate that a microfluidic design with tuneable rheological fluid properties and direct analysis of bright-field images can be suitable for the label-free mechanical phenotyping of various cell lines.

关键词： 热能   动力   机械   应用   对策  

摘要： 在世界经济水平不断提升的同时,地球的环境问题也在逐年加剧,很多国家在开发新兴能源的同时,不得不继续沿用既有技术,在对传统能源进行利用时,必须进行技术的创新来满足新时代对能源的需要和要求。热能无疑仍是当今世界发展到今天最大的动力能源,如何更好地利用热能被越来越多的人重视着。笔者认为,对热能的利用必须结合计算机、信息科学、机械学、内燃机学等多方面的技术,相互融合才能够实现。如何促进资源更加环保、更加高效的在热能领域得到应用,促进国家经济的环保、持续、稳定发展,是当前我们迫切需要研究和解决的最大问题。