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991.
为了降低富营养化,实验中讨论了粉煤灰、活性炭两种吸附剂对人工配制的含磷废水的去除效果。从投药量、废水pH值以及振荡时间三个方面考察了对吸附作用的影响。实验结果显示:粉煤灰对磷的去除效果远比活性炭的好,而且还可达到以废治废的效果。粉煤灰、活性炭的最佳投药量分别为0.06g/ml、0.05g/ml;最佳pH值均为6;最佳振荡时间分别为5h、7h;在上述条件下,粉煤灰对磷的吸附率可达90.38%,而活性炭则为31.54%。  相似文献   
992.
对拜泉县生态农业建设与可持续发展的思考   总被引:2,自引:0,他引:2  
结合拜泉县生态农业建设的具体经验,介绍了生态建设的具体做法,总结了生态农业建设取得的成就,对县域生态农业建设具有一定的参考价值.  相似文献   
993.
本文着重介绍美国赛默飞世尔公司生产的FH-62-C14颗粒物监测仪的测量原理,并针对使用和维护中容易出现的故障,介绍使用及维护方法和要点,并通过经典重量法与FH-62-C14β射线颗粒物监测仪进行测量均值比对,验证了设备维护的效果,为环境监测工作者提供应用及维护方面的参考,以获得更加准确的监测数据。  相似文献   
994.
以铜镉渣为研究对象,采用酸浸-锌粉置换方法对有色冶炼铜镉渣中镉进行提取,通过单因素实验分别对酸浸及置换条件进行考察,确定了镉提取的最优条件:在硫酸浓度为60g/L、液固比8:1、浸出时间3h,温度60℃的条件下镉的浸出率达97%;采用锌粉置换,锌粉用量为理论用量的1.3倍、置换温度40℃、提取时间1h、浸出液pH为2.5时,镉的置换率在99%以上,海绵镉的品位达78%。  相似文献   
995.
湖北省近50年风灾灾情分布特征分析   总被引:2,自引:0,他引:2  
风灾是湖北省主要的气象灾害之一,每年对高层建筑施工、电力、通信设施等造成较大损失,还给农业生产带来严重影响。利用湖北省1963~2011年的风灾灾情资料,分析了全省各地风灾灾情发生的频次及分布特征。结果表明:湖北省的风灾灾情与地理分布相关,全省风灾灾情可分为4个区域带,兴山-保康、宣恩、五峰-宜昌、荆州-公安一带,是风灾灾情出现的最大风险区,其中兴山、长阳两地为最高发频次地区,而鄂西北等地很少出现风灾灾情;其次,这些灾情,季节性较强,93.9%风灾灾情出现在春夏两季,而秋冬两季出现风灾灾情较少;从1963~2011的风灾灾情5个10a统计资料来看,风灾灾情出现增加的趋势,两个高峰年相隔约25a,而高峰灾年3a左右。  相似文献   
996.
Yang  Sheng  Cheng  Yanping  Liu  Tong  Huang  Shaoping  Yin  Lihong  Pu  Yuepu  Liang  Geyu 《Environmental Chemistry Letters》2022,20(5):2951-2970
Environmental Chemistry Letters - During the Corona Virus Disease 2019 (COVID-19) pandemic, protective equipment, such as masks, gloves and shields, has become mandatory to prevent person-to-person...  相似文献   
997.
In this work, a series of novel proton-gradient-transfer acid complexes (PGTACs) were developed. Their physicochemical properties, including thermal stability, melting point, and Hammett acidity, were measured. The effects of catalyst loading, reaction temperature, and substrate expansion on the catalytic performance were systematically studied. It is found that the combination of bidentate N-heterocycle and H2SO4 (1:2 M ratio) could form simultaneously N–H covalent bond and N…H hydrogen bond, which makes the PGTACs excellent catalysts integrate the advantages of strong acids (high catalytic activity) and ionic liquids (phase separation) in the esterification reaction. Moreover, these PGTACs can be reused by convenient phase separation without obvious diminution of catalytic activity. It is concluded that these PGTACs are potential alternative candidates for esterification reaction in the process of industrial catalysis.  相似文献   
998.

Green finance is not just a global trend, but it has become an important channel for industrialized countries to achieve sustainable growth. However, few studies have discussed the environmental governance effects of green finance from the micro-firm level. Based on the data of Chinese A-share listed firms in heavily polluting industries, we, combining with property rights and environmental regulation, empirically research the influence of green finance on corporate environmental responsibility (CER) performance. Results indicate that green finance has a significant negative effect on the environmental responsibility of heavily polluting firms. The result remains after a series of robustness tests. In addition, property rights and environmental regulation play a moderating role in the above relationship. The negative impact of green finance on CER is stronger in private firms and firms in areas with low environmental regulation intensity. Moreover, we observe that green finance decreases the CER performance of heavily polluting firms by increasing financing constraints, reducing environmental investment, and diminishing technological innovation. This study identifies the external factors that influence CER and also provides implications and theoretical support for the government to improve the setting and the implementation of green finance policy in the future.

  相似文献   
999.

Local governments are the dominant players in haze pollution control; furthermore, financial power reconstruction affects the effectiveness of haze control. Government innovation preference achieves win-win results for environmental protection and economic development by increasing innovation support. Therefore, a moderating variable for government innovation preference was added to the fiscal decentralization effect on haze pollution, and their interactive effect on haze pollution was studied. This study was conducted in 30 provincial regions. Thus, the severity of regional haze pollution differs because of temporal heterogeneity and asynchronous development. Furthermore, we analyzed the impact on haze pollution from the perspectives of the temporal and spatial differences in different regions of China. The results indicate that (1) fiscal decentralization increases haze pollution, while government innovation preferences control it. (2) In a local evaluation model with a diversified background, fiscal decentralization restrains haze pollution, and pollution source complexity reduces government innovation preference’s control pollution function. The interaction term revealed that government innovation preferences had a significant moderating effect. (3) Fiscal decentralization and government innovation preferences control the heterogeneity of haze pollution in different regions.

  相似文献   
1000.
Yin  Li  Wang  Juan  Shi  Kaipian  Zhang  Yong  Xu  Ying  Kong  Desheng  Ni  Lixiao  Li  Shiyin 《Environmental science and pollution research international》2022,29(55):83211-83219
Environmental Science and Pollution Research - The protective mechanism of extracellular polymeric substance (EPS) secreted by a harmful cyanobacteria against tannins allelochemicals was explored...  相似文献   
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