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811.
Controlling the confounding factors on cardiovascular diseases, such as long-time trend, calendar effect, and meteorological factors, a generalized additive model (GAM) was used to investigate the short-term effects of air pollutants (PM10, SO2, and NO2) on daily cardiovascular admissions from March 1st to May 31st during 2007 to 2011 in Lanzhou, a heavily polluted city in western China. The influences of air pollutants were examined with different lag structures, and the potential effect modification by dust storm in spring was also investigated. Significant associations were found between air pollutants and hospital admissions for cardiovascular diseases both on dust event days and non-dust event days in spring. Air pollutants had lag effects on different age and gender groups. Relative risks (RRs) and their 95% confidence intervals (CIs) associated with a 10 μg/m3 increase were 1.14 (1.04~1.26) on lag1 for PM10, 1.31 (1.21~1.51) on lag01 for SO2, and 1.96 (1.49~2.57) on lag02 for NO2 on dust days. Stronger effects of air pollutants were observed for females and the elderly (≥60 years). Our analysis concluded that the effects of air pollutants on cardiovascular admissions on dust days were significantly stronger than non-dust days. The current study strengthens the evidence of effects of air pollution on health and dust-exacerbated cardiovascular admissions in Lanzhou.  相似文献   
812.
2.危害地震观测环境。地震前兆信息是弱信号信息,必须采用精密仪器设备来捕获地球物理场、地壳形变场、地应力场、地球化学场等的变化信息;同时.记录地震波的仪器也要求有足够的精确度,以便识别并分离出来自地球深部的更多信息,这就要求地震监测仪器本身具有很高的抗十扰能力,更重要的是在地震监测设施周围一定范围内不得有影响其工作效能的干扰源存在.  相似文献   
813.
结合最新的相关安全规程要求,通过对在用吊运熔融金属起重机钢丝绳缠绕系统的分析、研究,依据起重机械设计规范,对不同工况下钢丝绳缠绕系统分别提出两套优化方案,并通过实际应用情况验证优化方案的可行性。  相似文献   
814.
Environmentally friendly green composites were prepared by blending Wheat gluten (WG) as matrix, dialdehyde starch (DAS) as filler and glycerol as plasticizer followed by compression molding of the mixture at 110 °C. The properties of the WG/DAS composite are compared with those of the WG/native wheat starch (NWS) composites. While tensile strength and strain at break decrease with increasing NWS content in the WG/NWS composites, a small content of DAS could improve tensile strength and strain at break simultaneously in the WG/DAS composites. The WG/DAS composites exhibit reduced moisture absorption in comparison with the WG/NEW composites. Formation of chemical bonding between DAS and WG is beneficial for the dispersion of DAS in the WG matrix and WG/DAS composites exhibit improved mechanical properties and reduced moisture absorption over the WG/NWS composites.  相似文献   
815.
Sludge protein foaming solution was effectively decolorized and deodorized by gamma irradiation in the presence of hydrogen peroxide. The existence of a synergetic effect on the decolorization and the deodorization was demonstrated by means of UV/vis spectrophotometry, chemical, and sensory analyses every 14 days during 98 days of storage. Furthermore, the foamability was measured using the Ross–Miles method. Results showed that color, odor, and foamability of irradiated samples under hydrogen peroxide oxidation were significantly improved. Sensory evaluation indicated that irradiated samples under hydrogen peroxide oxidation were better than nonirradiated samples in odor, and color. Finally, a preliminary cost analysis revealed that 60Co γ-ray/H2O2 process was more cost-effective than the H2O2 alone.  相似文献   
816.
A signal-amplified mercury sensing biosensor with desired sensitivity was developed through firstly using the GFP mutant with fluorescence increasing response towards Hg2+ as the reporter module. The developed biosensor showed response for Hg2+ in a relatively wide range of 1–10,000 nmol/L, and the detection limit was improved one or two orders of magnitude in comparison with most metal-sensing biosensors in similar constructs. In addition, the biosensor could distinguish Hg2+ easily from multiple metal ions and displayed strong adaptability to extensive pH conditions (pH 4.0–10.0). More importantly, the developed biosensor was able to provide an initial assessment of Hg2+ spiked in the environmental water with the recoveries between 85.70% and 112.50%. The signal-amplified strategy performed by the modified reporter module will be widely applicable to many other whole-cell biosensors, meeting the practical requirements with sufficient sensing performance.  相似文献   
817.
818.
针对柴油发电机组产生的职业病危害因素及危害程度在评价报告中常常被评价人员忽略这一现状,结合柴油发电机房存在的主要职业病危害因素及特点进行分析,得出柴油发电机房在职业卫生评价工作中的关键点,以方便评价人员应用。  相似文献   
819.
Environmental Geochemistry and Health - This study investigated the environmental geochemical characteristics of rare-earth elements (REEs) in surface waters in the Huainan mining area, Anhui...  相似文献   
820.
Cao  Xinchun  Wu  Mengyang  Zheng  Yalian  Guo  Xiangping  Chen  Dan  Wang  Weiguang 《Regional Environmental Change》2018,18(2):465-475
Regional Environmental Change - China faces the dual challenge of water scarcity and food security with continued population growth. This paper explores methods to meet that demand without...  相似文献   
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