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221.
坚持以反映时代特征和实践要求的科学理论指导实践,并根据实践经验不断进行理论创新,是马克思主义认识论的本质要求.资源节约型和环境友好型社会的提出和建设,就是我们党在总结对人与自然关系认识的基础上,借鉴国外的发展经验和教训,运用马克思主义唯物史观指导社会主义建设实践的一个范例,是对马克思主义认识论的丰富和发展.  相似文献   
222.
ASBR反应器处理豆制品废水的试验   总被引:1,自引:1,他引:0  
王亮  李风亭  刘华 《环境工程》2006,24(1):18-21
采用厌氧序批式活性污泥法处理食品加工废水。试验研究了反应器的最佳进水、反应时间比,从而得出最低进水pH值和最少加碱量,同时还研究了反应器在常温和低温下的处理能力,以及pH冲击、搅拌频率、消毒液对反应器的影响。结果表明:最佳进水、反应时间比为2.5h4.5h,此时进水pH值降低到5.0,加碱量大大减少;CODCr去除率随温度的降低而降低,25℃时,CODCr去除率为83.45%,20℃时,CODCr去除率降至73%左右,15℃时,CODCr去除率只有57%左右;本工艺条件下最佳搅拌频率为每小时搅拌10min,反应器对pH冲击具有一定耐受能力,但消毒液对处理效果影响较大且恢复困难。  相似文献   
223.
汪洋 《环境保护》2006,(6):19-22
变人口大市为人力资源优势大市 人口问题实际上是一把"双刃剑",人口多是压力、是挑战,但如果开发利用得好,也可能转化为人力资源优势.对此,要结合实际,全面准确地加以把握.第一,准确把握中央强调人均GDP的战略意图,以人均水平论实力、看发展.中央在确定"十一五"的奋斗目标时,特别突出了人均GDP这个指标,体现了中央对经济社会发展中人口因素的高度重视,体现了中央把人的全面发展纳入经济社会发展全局来进行统筹考虑,推动经济社会发展切实转入科学发展轨道的战略意图.  相似文献   
224.
卧龙湖是辽宁西北半干旱区向中部平原湿润区过渡的生态敏感带,本文介绍了卧龙湖的历史与现状,分析了存在的主要问题,并从微观角度提出了保护卧龙湖湿地的具体措施。  相似文献   
225.
肖莉  边建东  王昕  施力 《化工环保》2006,26(6):514-517
采用溶胶-凝胶法制备锌铝助剂,该助剂于700℃焙烧后与流化催化裂化(FCC)催化剂进行机械混合,制得混合催化剂;在FCC烟气工业模拟装置上考察混合催化剂的脱硫活性,用混合催化剂的脱硫活性来反映锌铝助剂的脱硫性能。实验结果表明,氧化锌质量分数为10%的锌铝助剂的脱硫活性最佳,脱硫率达62.5%。采用红外光谱和X射线衍射(XRD)对锌铝助剂的脱硫机理进行了研究,红外分析结果表明,弱的L酸中心有利于锌铝助剂脱硫,XRD分析结果表明,锌铝助剂在锌铝尖晶石结构尚未完全形成时,存在较多的晶格缺陷,能够有效地吸附烟气中的SOx,将其转化为H2S。  相似文献   
226.

Papillary thyroid cancer (PTC) has inflicted huge threats to the health of mankind. Metal pollution could be a potential risk factor of PTC occurrence, but existing relevant epidemiological researches are limited. The current case-control study was designed to evaluate the relationships between exposure to multiple metals and the risk of PTC. A total of 262 histologically confirmed PTC cases were recruited. Age- and gender-matched controls were enrolled at the same time. Urine samples were used as biomarkers to reflect the levels of environmental exposure to 13 metals. Conditional logistic regression models were adopted to assess the potential association. Single-metal and multi-metal models were separately conducted to evaluate the impacts of single and co-exposure to 13 metals. The increased concentration of urinary Cd, Cu, Fe, and Pb quartiles was found significant correlated with PTC risk. We also found the decreased trends of urinary Se, Zn, and Mn quartiles with the ORs for PTC. These dose-response associations between Pb and PTC were observed in the single-metal model and remained significant in the multi-metal model (OR25-50th=1.39, OR50-75th=3.32, OR>75th=7.62, p for trend <0.001). Our study suggested that PTC was positively associated with urinary levels of Cd, Cu, Fe, Pb, and inversely associated with Se, Zn, and Mn. Targeted public health policies should be made to improve the environment and the recognition of potential risk factors. These findings need additional studies to confirm in other population.

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227.
A shortened version of Quick, Easy, Cheap, Effective, Rugged, and Safe method (QuEChERS) for determining the dissipation and residue of imidacloprid present in Zizania latifolia and purple sweet potato was established by using liquid chromatography-tandem mass spectrometry (LC-MS/MS). The average recoveries of imidacloprid in the two crops ranged from 82.12 to 113.79%, with relative standard deviation (RSD) of <7.32%. The dissipation dynamics of imidacloprid in Z. latifolia plants and purple sweet potato plants followed first-order kinetics, with half-lives of 3.2–5.5?days in each of sampling locations. The terminal imidacloprid residues in Z. latifolia and purple sweet potato at each of location were <0.005–0.120?mg kg?1. According to the risk assessment results, both the acute dietary risk quotient and chronic dietary risk quotient values were <1, indicating that imidacloprid is unlikely to pose health risks to humans with normal recommended use. The present study may serve as a valuable reference for the safe and reasonable use of imidacloprid in Z. latifolia and purple sweet potato fields.  相似文献   
228.
Environmental Science and Pollution Research - Nitrosamines (NAms) are potent genotoxic and carcinogenic but widely detected in drinking water. This study aimed to investigate the occurrence of...  相似文献   
229.
Wang  Jiaqing  Lu  Pei  Su  Wei  Xing  Yi  Li  Rui  Li  Yuran  Zhu  Tingyu  Yue  Huifang  Cui  Yongkang 《Environmental science and pollution research international》2019,26(20):20248-20263

Currently, activated coke is widely used in the removal of multiple pollutants from industrial flue gas. In this paper, a series of novel FexLayOz/AC catalysts was prepared by the incipient wetness impregnation for NH3-SCR denitrification reaction. The introduction of Fe-La bimetal oxides significantly improved the denitrification performance of activated coke at mid-high temperature, and 4% Fe0.3La0.7O1.5/AC exhibited a superior NOx conversion efficiency of 90.1% at 400 °C. The catalysts were further characterized by BET, SEM, XRD, Raman, EPR, XPS, FTIR, NH3-TPD, H2-TPR, et al., whose results showed that the perovskite-type oxide of LaFeO3 and oxygen vacancies were produced on the catalysts’ surfaces during roasting. Fe-La doping enhanced the amount of acid sites (mainly Lewis and other stronger acid sites) and the content of multifarious oxygen species, which were beneficial for NOx removal at mid-high temperature. Moreover, it was investigated that the effect of released CO from activated coke at mid-high temperature on the NOx removal through the lifetime test, in which it was found that a large amount of CO produced by pyrolysis of activated coke could promote the NOx removal, and long-term escaping of CO on the activated coke carrier did not have a significant negative impact on catalytic performance. The results of the TG-IR test showed that volatile matter is released from the activated coke while TG results showed that the weight loss rate of 4% Fe0.3La0.7O1.5/AC only was 0.0015~0.007%/min at 300–400 °C. Hence, 4% Fe0.3La0.7O1.5/AC had excellent thermal stability and denitrification performance to be continuously used at mid-high temperature. Finally, the mechanisms were proposed on the basis of experiments and characterization results.

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230.
Environmental Science and Pollution Research - Suicide prevention has become a public health issue of great concern. Previous studies proved that ambient temperature had an impact on suicide death,...  相似文献   
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