在用吊运熔融金属起重机主起升钢丝绳缠绕系统的优化研究

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。     

Nitrous oxide generation in denitrifying phosphorus removal process: main causes and control measures

Despite the many benefits of denitrifying phosphorus removal process, the significant generation of nitrous oxide (N₂O), a potent greenhouse gas, remains a problem for this innovative and promising process. To better understand and more effectively control N₂O generation in denitrifying phosphorus removal process, batch experiments were carried out to investigate the main causes of N₂O generation, based on which the control measures were subsequently proposed. The results showed that N₂O generation accounted for 0.41 % of the total nitrogen removal in denitrifying phosphorus removal process, whereas, in contrast, almost no N₂O was generated in conventional denitrification process. It was further demonstrated that the weak competition of N₂O reductase for electrons and the high nitrite accumulation were the two main causes for N₂O generation, evidenced by N₂O production and reduction rates under different conditions. Accordingly, the reduction of N₂O generation was successfully achieved via two control measures: (1) the use of continuous nitrate addition reducing N₂O generation by around 91.4 % and (2) the use of propionate as the carbon source reducing N₂O generation by around 69.8 %.     

Synergetic decolorization and deodorization of sludge protein foaming solution by 60Co γ-ray irradiation/H2O2 oxidation

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.     

融雪剂对大叶黄杨生长和生理特性的影响

为了研究融雪剂对道路绿化植物的影响,以大叶黄杨（Euonymus japonicus Thunb）为研究材料,研究了其在3种融雪剂（JLR-01、LBR-4、芦笛一号）不同施用量影响下的生长量和生理特性。结果表明：随着融雪剂LBR-4和芦笛一号的施用量的增大,大叶黄杨叶片的相对生长量和株高相对生长量、光合速率（Pn）、水分利用效率（WUE）、蒸腾速率（Tr）和气孔导度（Gs）随之减小,而低施用量的融雪剂JLR-01对大叶黄杨生长量、Pn、WUE和Tr有促进作用。随着融雪剂作用时间的延长,3种融雪剂的Pn和WUE也随之减小,Tr则是先减小后有所增大。当融雪剂施用量较小和胁迫时间较短时,Pn下降是因为气孔关闭;而当施用量较大和胁迫时间较长时,Pn下降是因为叶肉同化能力下降;3种融雪剂对大叶黄杨的胁迫程度由大到小的次序为：芦笛一号〉LBR-4〉JLR-01;大叶黄杨对3种融雪剂施用量的忍耐阈值在80 g.m-2左右,大叶黄杨对施用LBR-4和芦笛一号的耐受时间阈值大约为3周,对施用JLR-01的耐受时间阈值为3周以上。     

An empirical analysis on the impact of environmental regulations on pork trade:evidence from China

This paper uses the gravity model to examine the effect of environmental regulations on pork trade flows between different regions within China.We apply a linear programming tool to estimate pork trade flows from 2000 to 2008,and discuss the environmental acts on livestock pollution and income level to proxy environmental regulations.We use OLS regression and panel data with dummy variable in the cross-sectional GLS estimation.Our results indicate that the gap of environmental regulations between trade partners has a positive relationship with pork trade flows,and the difference in environmental regulations changes the traditional comparative advantage pattern to some extent.This paper provides convincing evidence for the pollution haven effect on livestock in China.     

Bioaccumulation of dichlorodiphenyltrichloroethanes (DDTs) in carp in a water/sediment microcosm: important role of sediment particulate matter and bioturbation

Environmental Science and Pollution Research - Sediments are reservoirs and sources of DDTs to the aquatic ecosystem. However, the role of sediment particulate matter and benthic organisms in...     

水源地生态补偿机制研究进展

水源地生态补偿机制是一种调动水源地生态保护的经济手段。本文首先从生态补偿的概念、特征、目标与原则、主客体分析、补偿标准和补偿方式等方面综述了水源地生态补偿的发展现状与存在的问题。国外水源地生态补偿起步早、发展成熟;国内起步相对较晚且不完善,存在补偿标准偏低、资金来源单一、监督评估体系几乎空白等问题。通过综述水源地生态补偿实施效益评估方面的研究及案例发现,尽管国内外已有相关学者开始探索评价生态补偿政策的实施效果,但仍缺乏对生态补偿政策的有效监管与效益评估方法。针对以上问题,本研究提出通过拓展资金渠道,引导市场化资金募集方式;因地制宜,多重补偿方式相互结合;建立水源地生态补偿实施效益评估机制等几方面建议,以此完善水源地生态补偿机制的建立与优化。最后,本文指出采用定性描述与定量指标相结合,探索全面、有效与可行的水源地生态补偿机制实施效果监督与评估体系作为今后水源地生态补偿的主要研究方向。     

建筑施工中临边高处坠落危险源影响空间建模

将建筑施工中临边坠落的特性模型化,对于预防建筑施工中伤亡事故具有重要的意义。在分析人或物临边高处坠落事故特点的基础上,给出施工工作面内外2种危险源影响空间范围的定义及其数学表达函数,构建相应的危险源影响空间中危害能量分布的数学模型,提出它对人体不同部位伤害程度的评估分析思路,并在大面积碰撞和小面积碰撞2种情况下,建立该危害能量对人体头枕部伤害程度的评估分析方法。通过上海某个6层框架结构教学楼案例,对上述数学模型和评估分析方法进行验证。这为在进行施工计划安排时,考虑危险源影响空间的影响,降低安全事故发生的可能性创造条件,也为安全事故事前预防提供新思路。