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611.
This paper presents a wireless, passive, remote query CO2 sensor comprising a ribbon-like magnetoelastic thick-film coated with a mass-changing CO2 responsive polymer synthesized from acrylamide and isooctylacrylate. In response to a magnetic field impulse, the magnetostrictive magnetoelastic sensor vibrates at a characteristic resonant frequency that is inversely dependent upon the mass of the attached CO2 responsive polymer. The mechanical vibrations of the magnetostrictive sensor launch magnetic flux, which can be detected remotely using a pickup coil. By monitoring the resonant frequency of the passive sensor, the atmospheric CO2 concentration can be determined without the need for physical connections to the sensor or specific alignment requirements. The effect of humidity and the CO2 responsive copolymer composition on the measurement sensitivity are reported. Greatest sensitivity is achieved with a polymer comprising a 1:1 mole ratio of acrylamide to isooctyl acrylate. A 0.7% change in atmospheric CO2 concentration can be detected for a 20 microns thick polymer coated sensor. 相似文献
612.
正Due to its long-range transport in the atmosphere,mercury is a pollutant of global concern with health risks to humans and ecosystems worldwide(Li et al.,2012;Lindqvist et al.,1991;Liu et al.,2012a;Tang et al.,2016;Wang et al.,2015;Shao et al.,2016).Atmospheric mercury,mainly from emission from various natural and anthropogenic sources and 相似文献
613.
针对普通碳材料吸附BPA需要过滤或离心等复杂过程,将Fe3O4晶体沉积到多壁碳纳米管(MWCNTs)表面,合成饱和磁化度为23.3 emu/g的磁性多壁碳纳米管(MMWCNTs)以实现简便的固液分离.MMWCNTs对水相BPA的吸附是一个快速过程,饱和吸附量为14.9 mg/g.MMWCNTs对水相BPA的吸附过程△G为负值,是一个自发过程;△H为负值,是一个放热过程;△S为正值,是一个熵增过程.MMWCNTs对BPA的吸附具有物理吸附特征,MMWCNTs与BPA之间的相互作用力主要为范德华力. 相似文献
614.
Environmental degradation caused by human activities is of concern to society, government, industry, companies, and the people who are able to enjoy improved lifestyles because of industrial activities. However, all of these parties also have a responsibility to support and conserve the environment and act responsibly toward the earth. This article, which includes a systematic literature review and draws upon the authors’ practical experience, summarizes the benefits, motives, and difficulties in implementing environmental management systems using the International Organization for Standardization's (ISO) 14001 framework. 相似文献
615.
Sun Dongying Cai Siqin Yuan Xiaomeng Zhao Chanchan Gu Jiarong Chen Zhisong Sun Huaping 《Environmental geochemistry and health》2022,44(9):2987-3006
Environmental Geochemistry and Health - In this study, carbon emissions from agricultural energy consumption (CEAEC) are fully analyzed using data from the Yangtze River Economic Belt (YEB) between... 相似文献
616.
进入21世纪以来,保护生态环境和可持续发展已成为当下横置在世界各国面前的一道难题.论文根据"REVIT杯盘锦红海滩湿地公园候鸟之家设计大赛"所提供的条件和要求,秉着实现高速可持续发展的同时,最大限度地保留原有自然环境的原则,完成了盘锦红海滩湿地公园候鸟之家的筑内坏境、外环境、能源系统、水系统、材料选择等方面绿色策略的选择与应用.最终力求在人类活动需求与减少建筑对环境的影响之间寻找一个平衡点,从而实现可持续发展,永远保持绿色环境. 相似文献
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619.
2008年初冰雪灾害对生命线工程的几点启示 总被引:2,自引:0,他引:2
2008冰雪灾害对我国生命线工程造成了巨大损失。本文分析了雪灾对生命线工程造成损失的程度、特点、致灾因子、及其生命线工程之间的关联性,对我国生命线工程建设提出了几点建议,呼吁国家要重视防灾减灾工程的人才培养和科技投入。 相似文献
620.
We studied the energy and economic flow of six types of homegardens in Sanjia village, SW China. Our study showed that the energy input of six types of homegardens averaged 99.11-175.65 x 1010J/ha, the energy output was 102.30-159.83 x 1010J/ha and the ratio of input/output ranged between 1:0.880-1:1.416. The ratios of input to output of home-gardens that prioritized cultivation of crops were higher than for homegardens that prioritized animal husbandry or other economic activities. The economic ratio of input/ output of six types of homegardens varied between 1:0.997-1:1.376 and the economic output ranged between 2480.0-10131.5 RMB/yr. We concluded that the homegarden systems of Sanjia village are high in the input and output of energy and cash flow, and can provide a basis for designing models of farm economy in rural subtropical areas. 相似文献