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861.
二次加压泵房噪声与振动治理 总被引:1,自引:1,他引:0
针对楼盘受低频噪声的困扰,本文提出建筑物内的设备运行造成的结构传声是扰民的主要声源。研究了二次加压泵房噪声与振动的特性,在此基础上研究了设备的隔声、隔振技术,并成功应用于实际项目中。 相似文献
862.
通过运用ADMS模型,对2万m3原油储罐发生火灾爆炸事故时有毒有害气体及燃烧次生污染物的环境影响进行预测。结果表明,其产生的废气污染物对环境影响较大;在火灾持续6h的情况下,产生的主要废气污染物在距离事故中心120m范围内的人员将有半数死亡;距120~240m范围内造成组织缺氧;距240~4725m人员不会有生命危险;距离4725m范围内污染物的浓度超出车间最高允许浓度要求。同时提出了相应的环境风险管理措施,为今后类似事故环境影响评价作借鉴,为环保部门环境管理提供参考。 相似文献
863.
Validation of MODIS aerosol retrievals and evaluation of potential cloud contamination in East Asia 总被引:10,自引:0,他引:10
MODIS aerosol retrievals onboard Terra/Aqua and ground truth data obtained from AERONET(Aerosol Robtic Network) solar direct radiance measurements are collocated to evaluate the quality of the former in East Asia. AERONET stations in East Asia are separated into two groups according to their locations and the preliminary validation results for each station. The validation results showed that the accuracy of MODIS aerosol retrievals in East Asia is a little worse than that obtained in other regions such as Eastern U.S., Western Europe, Brazil and so on. The primary reason is due to the improper aerosol model used in MODIS aerosol retrieval algorithm, so it is of significance to characterize aerosol properties properly according to long term ground-based remote sensing or other relevant in situ observations in order to improve MODIS retrievals in East Asia. Cloud contamination is proved to be one of large errors, which is demonstrated by the significant relation between MODIS aerosol retrievals versus cloud fraction, as well as notable improvement of linear relation between satellite and ground aerosol data after potential cloud contamination screened. Hence, it is suggested that more stringent clear sky condition be set in use of MODIS aerosol data. It should be pointed out that the improvement might be offset by other error sources in some cases because of complex relation between different errors. Large seasonal variation of surface reflection and uncertainties associated with it result in large intercepts and random error in MODIS aerosol retrievals in northern inland of East Asia. It remains to be a big problem to retrieve aerosols accurately in inland characterized by relatively larger surface reflection than the requirement in MODIS aerosol retrieval algorithm. 相似文献
864.
Ground-based simultaneous observations of sun direct and scattering radiation were carded out in Dunhuang for nearly 2 years.Aerosol optical depth, Angstrom wavelength exponent and size distribution were obtained from solar extinction and sky radiation. Water vapor content was obtained from sun direct radiation measurement at 940 nm. Relationship between aerosol properties and water vapor was discussed. Results showed that distinct seasonality of aerosol optical depth and Angstrom wavelength exponent was corresponding to seasonal variation of dust activity. Aerosol relative size distribution kept stable and volume concentration change was the reason resulting in variation of aerosol optical depth. Water vapor had minor effects on aerosol optical and physical properties. 相似文献
865.
Min Shang Yadong Kong Zhijuan Yang Rong Cheng Xiang Zheng Yi Liu Tongping Chen 《Frontiers of Environmental Science & Engineering》2023,17(3):27
866.
在兰州市不同室外环境区域布设4个采样点,使用PSW-6型安德森(Andersen)6级筛孔撞击式空气微生物采样器采集大气细菌气溶胶,分析其浓度和粒径日变化特征。结果表明,不同季节各采样点的大气细菌气溶胶浓度上午时段为88 CFU/m3~1 335 CFU/m3,下午时段为78 CFU/m3~865 CFU/m3。除了夏季兴隆山上午时段外,其余不同季节各采样点上、下午时段的大气细菌气溶胶粒径均主要分布于Ⅰ级—Ⅳ级(>2.10μm),占比为 70.54%~93.94%;Ⅴ级(1.10 μm~2.10μm)和Ⅵ级(0.65 μm~1.10 μm)大气细菌粒子占比较低,仅为6.06%~29.46%。 相似文献
867.
Negative events within and outside of work can disrupt coworkers' relationships, triggering a re-evaluation of relationship quality. The subjective experience of these events – which we term relationship threats – harms relationships, resulting in long-lasting negative interpersonal and organizational consequences. Coworkers' responses to a relationship threat determine whether relationships are repaired or whether the threat leads to a loss of commitment, lowered satisfaction, and increased negative affect. Because of the critical role that relationships play in organizational life, it is vital that we have a comprehensive understanding of the repair process. To date, researchers have focused on one of three repair processes: trust repair. In reconceptualizing relationship repair, we flesh out the remaining two processes: relationship work and sensemaking. Our reconceptualization balances the restorative actions that mitigate in-the-moment harm with those that sustain these benefits over time. We expand our understanding of relationship repair by highlighting the role that narrative foundations play in determining a relationships' vulnerabilities and determining effective repair processes. We highlight the importance of considering relationship threats as events embedded within a relationship's history; identify narrative foundations as a bridging mechanism between disrupted relationships and their repair; and expand our conceptualization of the processes that repair relationships. 相似文献
868.
869.
870.
讨论了2000年02月~2019年08月不同分辨率、算法中等分辨率成像光谱仪(MODIS)气溶胶光学厚度(AOD)产品在不同季节、区域、下垫面条件下中国区域的精度和适用性,在像元尺度上对比了重采样降低分辨率后的多角度大气校正(MAIAC)AOD数据与其他产品的精度.研究表明:在同等验证条件下,相较于暗目标算法(DT)、深蓝算法(DB)和暗目标与深蓝结合算法(DTB),1km MAIAC AOD产品在中国地区与AERONET站点AOD观测数据整体一致性最高,R2达到0.891,均方根误差(RMSE)仅为0.126,超过75%的验证样本落在期望误差线(EE)范围内;同时,该产品受季节、区域和下垫面变化影响也最小,其中秋季R2达到0.917,RMSE为0.111,样本落在EE内的比例达到80.11%.3km DT算法AOD产品在植被覆盖率较大的森林和农田区域优于1km MAIAC AOD产品,在植被覆盖率较小的草地和城市区域则差于1km MAIAC AOD产品,且该产品在不同季节均存在AOD高估问题,其中,夏季高估程度最高(平均相对误差(RMB)=1.622,AOD值高估62.2%).DB在长三角和珠三角地区存在AOD被低估的现象.DTB算法兼顾了DT算法和DB算法的优缺点,DTB算法AOD产品的相关性一般高于DB算法AOD产品,样本被高估程度一般低于DT算法AOD产品.通过重采样方法降低1km MAIAC AOD产品分辨率后,相同尺度下的MAIAC AOD数据精度优于DT算法、DB算法和DTB算法AOD产品,因此,MAIAC算法更适用于小尺度城市群集中区域的大气环境监测. 相似文献