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51.
Li Lin Harry Haoxiang Wang Yuewei Liu Ciyong Lu Weiqing Chen Vivian Yawei Guo 《Indoor air》2021,31(6):2158-2166
A cross-sectional study was conducted to investigate the impact of solid fuel use for heating and cooking on blood pressure (BP) and hypertension, using data from the China Health and Retirement Longitudinal Study (CHARLS). The primary fuels used for indoor heating and cooking were collected by questionnaires, respectively. Hypertension was defined based on self-report of physician's diagnosis, and/or measured BP, and/or anti-hypertensive medication use. Multivariate logistic regression models were constructed to assess the associations. Among 10 450 eligible participants, 68.2% and 57.2% used indoor solid fuel for heating and cooking, respectively. Compared with none/clean fuel users, solid fuel for heating was associated with elevated BP (adjusted β: 2.02, 95% CI: 1.04–3.01 for systolic BP; adjusted β: 1.36, 95% CI: 0.78–1.94 for diastolic BP) and increased risk of hypertension (adjusted odds ratio: 1.15, 95% CI: 1.03–1.29). The impact of indoor solid fuel for heating on BP was more evident in rural and north residents, and hypertensive patients. We did not detect any significant associations between solid fuel use for cooking and BP/hypertension. Indoor solid fuel use is prevalent in China, especially in the rural areas. Its negative impact on BP suggested that modernization of household fuel use may help to reduce the burden of hypertension in China. 相似文献
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53.
Lopez Daniel Andres Sanchez Chagas Luciana Gomes Batista Aline Domingues Guaita Maria Gabriella Detone Amorin Luís Henrique Cardozo da Silva Paulo Rogério Catarini Yamanishi Gustavo Zaia Dimas Augusto Morozin de Santana Henrique Urbano Alexandre 《Journal of Materials Science: Materials in Electronics》2021,32(13):17462-17472
Journal of Materials Science: Materials in Electronics - The increasing demand for lithium-ion batteries has stimulated the investigation of new compounds in order to reduce the costs and the... 相似文献
54.
55.
Jiajia Lu Guangfu Qian Lin Luo Huibing He Shibin Yin 《International Journal of Hydrogen Energy》2021,46(1):676-682
The tungsten trioxide attracts less attention due to the low electron transfer kinetics that hinders the interaction of electrons and ions during the hydrogen evolution reaction (HER). But the oxygen vacancy strategy can inspire its electrocatalytic activity for HER because it has a positive effect on improving the charge transfer and compensating for the weak hydrogen adsorption of the tungsten trioxide. By synthesizing a series of substoichiometric tungsten oxides, we reveal the linear relationship between the catalytic activity and the content of oxygen vacancies, which indicates that the oxygen vacancy strategy is an achievable route to enhance the HER for metal oxides. 相似文献
56.
目的 检测水产品及养殖水中丁香酚类化合物。方法 应用食品补充检验方法BJS 201908《水产品及水中丁香酚类化合物的测定》,以海水鱼、淡水鱼、海水虾、淡水虾及养殖水作为基质,测定6种丁香酚类化合物的含量。结果 通过对实际样品测定后发现,在水产品中检出了丁香酚类化合物,主要为丁香酚,检出率为28.9%,其中海水鱼相对突出。结论 本研究为丁香酚作为渔用麻醉剂提供了方法论,为丁香酚类化合物在水产运输的合理使用提供理论依据。 相似文献
57.
在城市化快速进程的背景下,城市
街区PM2.5污染日益严重,本文选取哈尔滨
在不同季节的典型街谷空间,对以叶面积密
度(LA D)、叶面积指数(LAI)为实测要素
的绿色界面指数以及PM2.5浓度进行实测对
比研究。通过对实测数据的分析和挖掘,最
终得出如下结论:首先,典型街谷空间PM2.5
时段浓度呈现上午比下午平均高37.75%,冬
季比夏季高4.7倍的特征;其次,街谷空间的
灌木界面对PM2.5浓度场平均积极贡献率为
18.62%;最后,对PM2.5的衰减率与实测街
谷绿色界面的叶面积密度(LAD)与叶面积
指数(LAI)进行相关性分析,结果显示街谷
绿色界面对PM2.5浓度的衰减作用与叶面积
密度(LAD)呈显著负相关关系,与叶面积指
数(LAI)的相关性程度较弱。 相似文献
58.
Carboxyl-terminated polybutadiene (CTPB) is a widely used telechelic liquid rubber, which is mainly prepared by anionic or free-radical polymerization of 1,3-butadiene. It is known that the microstructure of liquid polybutadiene rubber largely affects its processability and mechanical properties. However, it is hard to control its microstructure in the free radical or anionic polymerization. In this study, a series of CTPB with high cis-1,4 content has been prepared for the first time via the oxidolysis and selective oxidation of cis-polybutadiene rubber (BR). Hydrogenation of their CC double bonds with p-toluenesulfonyl hydrazide/tri-n-propylamine (TSH/TPA) reagents afforded carboxyl-terminated polyethylenes (CTPE). For comparison, commercial CTPB (FCTPB), prepared by free-radical polymerization of 1,3-butadiene, was also hydrogenated and gave FCTPE with more ethyl branches. Linear CTPE (L-CTPE) was synthesized by ring-opening metathesis polymerization of 1,5-cyclooctadiene in the presence of maleic acid and subsequent hydrogenation. The microstructure of the polymers was established by FT-IR, 1H NMR, 13C NMR, and GPC and their thermal properties were determined by DSC and TGA. © 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019 , 136, 46934. 相似文献
59.