Exploration of Science Parks

1 DEVELOPMENT OF SCIENCE PARKSThe concept of science park originated in the US. Manyterms are used to describe science parks, such as researchpark, technology park, science centre, research centre,innovation centre, and with various combination of these(MacDonald, 1987). The first science park in the worldis Stanford Industrial Park established in 1951. In 1955,only seven companies were located in the park. By 1980there were ninety companies including Hewlett PackardCompany, whic…     

Acceleration of floc-water separation and floc reduction with magnetic nanoparticles during demulsification of complex waste cutting emulsions

Waste cutting emulsions are difficult to treat efficiently owing to their complex composition and stable emulsified structure. As an important treatment method for emulsions, chemical demulsification is faced with challenges such as low flocs–water separation rates and high sludge production. Hence, in this study, Fe₃O₄ magnetic nanoparticles (MNPs) were used to enhance chemical demulsification performance for treating waste cutting emulsions under a magnetic field. The addition of MNPs significantly decreased the time required to attain sludge–water separation and sludge compression equilibrium, from 210 to 20 min. In addition, the volume percentage of sludge produced at the equilibrium state was reduced from 45% to 10%. This excellent flocculation–separation performance was stable over a pH range of 3–11. The magnetization of the flocculants and oil droplets to form a flocculant–MNP–oil droplet composite, and the magnetic transfer of the composite were two key processes that enhanced the separation of cutting emulsions. Specifically, the interactions among MNPs, flocculants, and oil droplets were important in the magnetization process, which was controlled by the structures and properties of the three components. Under the magnetic field, the magnetized flocculant–MNP–oil droplet composites were considerably accelerated and separated from water, and the sludge was simultaneously compressed. Thus, this study expands the applicability of magnetic separation techniques in the treatment of complex waste cutting emulsions.     

Coupling mechanism of activated carbon mixed with dust for flue gas desulfurization and denitrification

To clarify the effect of coking dust, sintering dust and fly ash on the activity of activated carbon for various industrial flue gas desulfurization and denitrification, the coupling mechanism of the mixed activated carbon and dust was investigated to provide theoretical reference for the stable operation. The results show that coking dust had 34% desulfurization efficiency and 10% denitrification efficiency; correspondingly, sintering dust and fly ash had no obvious desulfurization and denitrification activities. For the mixture of activated carbon and dust, the coking dust reduced the desulfurization and denitrification efficiencies by blocking the pores of activated carbon, and its inhibiting effect on activated carbon was larger than its own desulfurization and denitrification activity. The sintering dust also reduced the desulfurization efficiency on the activated carbon while enhancing the denitrification efficiency. Fly ash blocked the pores of activated carbon and reduced its reaction activity. The reaction activity of coking dust mainly came from the surface functional groups, similar to that of activated carbon. The reaction activity of sintering dust mainly came from the oxidative property of Fe₂O₃, which oxidized NO to NO₂ and promoted the fast selectively catalytic reduction (SCR) of NO to form N₂. Sintering dust was activated by the joint action of activated carbon, and both had a coupling function. Sintering dust enhanced the adsorption and oxidation of NO, and activated carbon further promoted the reduction of NO_x by NH₃; thus, the denitrification efficiency increased by 5%-7% on the activated carbon.     

新冠肺炎疫情期间我国居民洗手行为研究

直接接触和飞沫传播等方式是新型冠状病毒传播的主要途径,合理的洗手行为是切断暴露途径和降低病毒感染风险的有效防控措施,对于新型冠状病毒肺炎（COVID-19,简称“新冠肺炎”）疫情的防控具有重要的作用.该研究于2020年2月25日—3月14日,采用电子问卷的方式调查了覆盖我国31个省（自治区、直辖市）1 728个县（区）18岁及以上的居民,收集共计8 330名成人的洗手情形及洗手时长等信息,分析不同暴露情景下的洗手行为及其影响因素.结果表明:女性、城市地区居民在洗手比例和洗手时长上均分别高于男性、农村地区居民.人群在一般暴露情景下的洗手比例较高,而对于病毒感染风险较高的暴露情景（如咳嗽或打喷嚏后、接触他人后等）的洗手率（分别为73.6%和83.9%）排名靠后,说明人群对病毒的传播途径和防护措施有待深入理解;在洗手时间上,根据WHO规定的洗手时长标准（20 s）,仅有41.7%的人群洗手时长合格（大于20 s）,城区居民洗手时长的合格率（42.0%）显著高于农村地区（39.7%）;总体上,具有外出经历的人群洗手比例较未曾外出的人群高,新冠肺炎疫情期间居住地是否存在新冠肺炎疑似和确诊病例显著影响居民的洗手行为,但是疫情最严重的地区居民的洗手时长合格率（37.2%）最低,反而疫情最轻的地区居民的洗手时长合格率（43.6%）最高,说明居民的洗手行为可能受疫情等多方面的影响.研究显示,相比于非疫情期间而言,疫情期间我国居民洗手行为发生率提高,洗手时长合格率提高,但是仍然水平偏低.应提高居民洗手行为意识,科学地执行洗手这一防护措施,相关政策制定以及个人防护应当进一步关注和重视洗手行为的防疫作用.      

砷、汞对植物毒性影响及其迁移富集效应探讨

介绍了自然环境中砷、汞的污染来源与污染现状,探讨了砷、汞对植物生长发育、光合作用和抗氧化能力的影响;为了缓解砷、汞对植物的毒害作用,可以添加新一代植物激素、营养元素和改良剂。分析发现,植物对不同浓度砷和汞的敏感程度并不相同,可利用特定植物的富集作用进行环境修复。当前研究主要集中于植物对砷、汞的吸收和转运生理机制,今后还需要加强对超积累植物分子基础的探索。     

小型水利工程项目对环境的影响分析与研究

水利工程是农业项目发展的重要组成部分之一,小型水利工程项目的建设对环境的影响不容忽视。因此,以环境影响因素为基础对水利工程项目进行详细的设计是保障工程有序进行的重要前提。环境影响评价工作直接影响水利工程建设方案的价值,是判断工程设计方案可行性的重要依据。通过对小型水利工程项目对环境的影响进行调查和分析以及对水利工程对周围环境带来的影响进行评析,分析和介绍了环境影响评价的原则和思想,进而分析了水利工程建设与环境之间的关系,希望为建设水利项目提供借鉴作用。     

无盘网络系统的介绍和应用

无盘网络系统是一种很适合在计算机配置较固定、软件程序较划一的网络环境中运行的网络系统,随着电脑教育的规模扩大,网络教室的普及,发展也非常快.本文简述了其产生环境、功能介绍,针对其优势和不足说明了无盘网络系统的应用前景是非常广阔的.     

重庆城市餐厨垃圾管理对策的初步研究

餐厨垃圾对环境的污染和人们身心健康的危害日益显现,重庆市对餐厨垃圾的统一管理与处置基本还处于空白状态.本文介绍了国内外餐厨垃圾管理的政策和措施,剖析重庆城市餐厨垃圾污染的现状及原因,进而提出全市餐厨垃圾管理的总体思路,并着重从健全法律法规体系、转变政府管理职能、建立市场化机制及引导公众参与等方面提出了相应的对策建议.     

利用脉冲澄清池补充处理生化后废水的运行结果和分析

通过对脉冲澄清池在综合废水处理中运行效果的跟踪分析,确定出利用脉冲澄清池补充处理生化后废水(悬浮物、COD_(cr)、BOD_5等)的影响程度,为其在综合废水处理工艺中的应用及其局限性,提供了必要的参考依据.     

重金属对土壤—植物系统中氮的转化与NO3-淋失影响的研究

本项研究采用“微宇宙”方法,在实验室植物生长箱可控条件下,进行动态模拟实验。实验选择了七种重金属,按照土壤阳离子代换量计算出三种不同等级的土壤重金属剂量,研究它们对京津渤地区典型土壤(碳酸盐草甸土)中氮的转化与NO_3~-淋失影响。实验结果表明:七种重金属对该类土壤中氮的转化与NO_3~-淋失量有明显影响,但其表现的程度和特征有很大差异。其作用强度的次序为:Hg~(2 )>>Cd~(2 )>>Ni~(2 )>>Zn~(2 )>Pb~(2 )>Cu~(2 )>Cr~(3 )。各重金属作用的持续时间不同:Hg~(2 )、Cd~(2 )达7—11周以上,而其余重金属在4—7周。实验结论:本地区碳酸盐土壤虽然对重金属有较大的容量,但从土壤—植物系统污染生态学角度,仍可选择NO_3~-作为一项反映重金属对土壤生态毒性的早期诊断指标。