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Current state and future perspectives of sewer networks in urban China

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Frontiers of Environmental Science & Engineering 2018年第3期12卷 13-28页

作者： Dong Huang xiuhong liu Songzhu Jiang Hongchen Wang Junyan Wang Yuankai Zhang School of Environment & Resource Renmin University of China Beijing 100872 China Chengdu Urban and Rural Construction Commission Chengdu 610094 China

Chinese authorities and the public have largely ignored sewer networks; however, various problems are emerging nationwide with the increase construction of new sewers. The current state of sewer network construction, administration, and maintenance in China is comprehensively reviewed in this study. Serving about 444 million people, 511,200 km of sewer lines are located in urban areas. In 2014,$7 billion was invested in sewer network construction. However, both the sewer pervasion rate and the per capita sewer length were significantly lower than those in developed countries. Sewer administrative agencies in local governments are uncoordinated. Laws, regulations, and standards are incomplete, and some practices are unscientific. The future situation of sewer maintenance is extremely grim because sewer corrosion control measures have not been launched. Moreover, inspection and rehabilitation chiefly rely on traditional approaches. In contrast, the overall market share of innovative technologies is very low owing to high cost, funds shortage, and technical limitations. Approaches such-as liner inversion cured-in-place pipe, pull-in ultraviolet light cured liners, and spiral wound lining are applied mostly in economically developed regions. According to status and problem analyses, China＇s top priority will be to conduct aggressive maintenance work in sewer networks in the future. New technical route, corrosion control - periodic visualized inspection - trenchless rehabilitation, could be the best option for future sewer maintenance in China. Instmctions and opportunities for applying this technical route are discussed in detail in this study. *** factors in the development of sewer networks in China are suggested.

关键词： Sewer network China Management Sewer corrosion Sewer inspection Trenchless rehabilitation

Online control of biofilm and reducing carbon dosage in denitrifying biofilter： pilot and full-scale application

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Frontiers of Environmental Science & Engineering 2017年第1期11卷 59-66页

作者： xiuhong liu Hongchen Wang Qing Yang Jianmin Li Yuankai Zhang Yongzhen Peng School of Environment & Natural Resources Renmin University of China Beijing 100872 China Key Laboratory of Beijing for Water Quality Science and Water Environment Recovery Engineering Beijing University of Technology Beijing 100124 China

Denitrifying biofilter （DNBF） is widely used for advanced nitrogen removal in the reclaimed wastewater treatment plants （RWWTPs）. Manual control of DNBF easily led to unstable process performance and high cost. Consequently, there is a need to automatic control of two decisive operational processes, carbon dosage and backwash, in DNBF. In this study, online control of DNBF was investigated in the pilot-scale DNBF （600 m3·d-1） and then applied in the full-scale DNBF （ 10 ×10^4m^3·d-1）. A novel simple onhne control strategy for carbon dosage with the effluent mtrate as the sole control parameter was designed and tested in the pilot-scale DNBF. Backwash operation was optimized based on the backwash control strategy using turbidity as control parameter. Using the integrated control strategy, in the pilot-scale DNBF, highly efficient nitrate removal with effluent TN lower than 3 mg·L-1 was achieved and DNBF was not clogged any more. The online control strategy for carbon dosage was successfully applied in a RWWTE Using the online control strategy, the effluent nitrate concentration was controlled relatively stable and carbon dosage was saved for 18%.

关键词： Reclaimed water treatment Denitrifying biofilter Carbon dosage Backwash control

Nitrous oxide production during nitrogen removal from domestic wastewater in lab-scale sequencing batch reactor

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Journal of Environmental Sciences 2008年第6期20卷 641-645页

作者： liu xiuhong PENG Yi WU Changyong AKIO Takigawa PENG Yongzhen School of Municipal and Environmental Engineering Harbin Institute of Technology Harbin 150090 China Department of Civil Engineering Maebashi Institute of Technology Maebashi Japan School of Environmental and Energy Engineering Beijing University of Technology Beijing 100022 China

The production of N2O during nitrogen removal from real domestic wastewater was investigated in a lab-scale aerobic-anoxic sequencing batch reactor with a working volume of 14 L. The results showed that the total N2O-N production reached higher than 1.87 mg/L, and up to 4% of removed nitrogen was converted into N20. In addition, N20 led to a much higher greenhouse effect than CO2 during aerobic reaction phase, this proved that N2O production could not be neglected. The N2O-N production during nitrification was 1.85mg/L, whereas, during denitrification, no N2O was produced, nitrification was the main source of N2O production during nitrogen removal. Furthermore, during denitrification, the dissolved N2O at the end of aeration was found to be further reduced to N2. Denitrification thus had the potential of controlling N2O production.

关键词： N2O domestic wastewater nitrification denitrification

Aberrant DNA methylation patterns in cultured mouse embryos

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Progress in Natural Science:Materials International 2005年第12期15卷 1079-1083页

作者： HOU Jian,CUI xiuhong,LEI Tinghua,liu Lei,AN Xiaorong and CHEN Yongfu State Key Laboratory for Agrobiotechnology and Department of Animal Physiology,College of Biological Science,China Agricultural University,Beijing 100094,China State Key Laboratory for Agrobiotechnology and Department of Animal Physiology College of Biological Science China Agricultural University Beijing 100094 China

Mouse early embryos undergo genome-wide demethylation and remethylation events during pre-implantation *** methylation reprogramming is thought to be associated with development *** immunofluorescence staining with an antibody against 5-methylcytosine (MeC),we examined the genome methylation patterns of mouse embryos cultured in *** results did not show the difference in staining patterns between development-blocked two-cell embryos that cultured in vitro and the two-cell embryos that were freshly collected from the donor *** in vitro-arrested morulae displayed a strong positive staining when compared to the morulae freshly collected from the donor *** the blastocyst stage,although most embryos showed the expected methylation patterns,with highly stained inner cell mass (ICM) and weekly stained trophectoderm (TE),a proportion of embryos were dimly stained in both ICM and *** results indicated that the methylation profile of the embryos could be changed by culturing in vitro when the embryos were in the transition from morulae to blastocyst.

关键词： methylation mouse embryo 5-methylcytosine antibody

High performance optical sensor based on double compound symmetric gratings

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Chinese Optics Letters 2022年第2期20卷 40-44页

作者： Chaoying Shi xiuhong liu Jinhua Hu Haiyan Han Jijun Zhao School of Mathematics&Physics Hebei University of EngineeringHandan 056038China School of Information&Electrical Engineering Hebei University of EngineeringHandan 056038China

A high performance optical sensor based on a double compound symmetric gratings(DCSGs) structure is designed. The reflection spectrum of the DCSG is investigated by utilizing a method that combines a theoretical model with the eigenmode information of the grating structure. The theoretical results, which are observed to agree well with those acquired by rigorous coupled-wave analysis, show that the linewidth of the reflection spectrum decreases upon the increasing distance between the grating strips. This research work will lay a foundation for studying high performance integrated optical sensors in miniature nanostructures.

关键词： compound gratings sensitivity sensor figure of merit

Perfect absorption in a monolayer graphene at the near-infrared using a compound waveguide grating by robust critical coupling

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Chinese Optics Letters 2019年第1期17卷 5-8页

作者： Jinhua Hu Jia Fu xiuhong liu Danping Ren Jijun Zhao Yongqing Huang School of Information & Electrical Engineering Hebei University of Engineering School of Mathematics & Physics Hebei University of Engineering State Key Laboratory of Information Photonics and Optical Communications Beijing University of Posts and Telecommunications

We present a perfect graphene absorber with a compound waveguide grating at the near-infrared. The analytical approach is mainly based on the coupled leaky mode theory, which turns the design of the absorber to finding out the required leaky modes supported by the grating structure. Perfect absorption occurs only when the radiative loss of the leaky mode matches the intrinsic absorption loss, which is also named the critical coupling ***, we also demonstrate that the critical coupling of the system can be robustly controlled, and the perfect absorption wavelength can be easily tuned by adjusting the parameters of the compound waveguide grating.

关键词： Perfect absorption monolayer graphene critical coupling

制度、利益与观念:男女同龄退休政策改革研究——基于历史制度主义视角

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理论导刊 2010年第12期 17-20页

作者：刘秀红扬州大学社会发展学院江苏扬州225002

从历史制度主义视角分析,三种主要政治因素及其相互作用下的政治行为决定着男女同龄退休政策改革的过程和结果:制度因素,包括宪法的原则性规定、行政决策制度、妇联组织的地位与参与方式等;利益因素,女干部、女工人及以男性为主体的决... 详细信息

从历史制度主义视角分析,三种主要政治因素及其相互作用下的政治行为决定着男女同龄退休政策改革的过程和结果:制度因素,包括宪法的原则性规定、行政决策制度、妇联组织的地位与参与方式等;利益因素,女干部、女工人及以男性为主体的决策部门所具有的不同利益;观念因素,在社会发展背景下利益各方对性别平等和退休年龄关系的理解也即对实现男女平等途径的不同认识。由于社会性别观念的深入、社会性别主流化在我国的发展及人口老龄化背景下的劳动力问题和养老问题等常量的变化,男女同龄退休政策的改革将成为可能。

关键词：社会政策男女同龄退休历史制度主义制度利益观念

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东汉帝陵选址与血统传承因素

华夏考古 2022年第1期 84-88,115页

作者：刘秀红丁岩陕西学前师范学院历史文化与旅游学院陕西西安市710100 陕西省考古研究院陕西西安市710054

洛阳附近的11座东汉帝陵形成了邙山和洛南两个陵区,这种布局是沿袭战国秦至西汉时期“旁近祖考”帝陵选址的原则。为保持同一陵区内父子相随的血统世系的有序传承,同辈帝王的继任者陵墓一般须离开前任陵墓所在陵区而另置他处。

关键词：邙山陵区洛南陵区血统世系有序传承

相容性单木生物量模型估计方法的比较——以青冈栎为例

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林业科学 2020年第9期56卷 164-173页

作者：刘秀红姜春前徐睿何潇齐梦娟中国林业科学研究院林业研究所/国家林业和草原局林木培育重点实验室北京100091 中国林业科学研究院资源信息研究所北京100091

【目的】生物量模型是估算森林生物量的有效手段,非线性联立方程组是构建相容性生物量模型的常见方法。本研究以青冈栎为例,比较常用的2种生物量模型构建方法和3种参数估计算法,以期选出最好的生物量模型构建方法和算法,为生物量的模型... 详细信息

【目的】生物量模型是估算森林生物量的有效手段,非线性联立方程组是构建相容性生物量模型的常见方法。本研究以青冈栎为例,比较常用的2种生物量模型构建方法和3种参数估计算法,以期选出最好的生物量模型构建方法和算法,为生物量的模型计算和研究提供技术支撑。【方法】以南方25株青冈栎地上生物量实测数据为例,选择比例总量直接控制和代数和控制2种结构形式的相容性生物量模型,分别使用普通最小二乘法、二阶最小二乘法和三阶最小二乘法作为模型参数估计算法,建立地上总生物量与各组分生物量的相容性模型,比较不同相容性生物量模型的拟合效果。【结果】在3种参数估计算法下,2种结构的生物量模型均能解决地上生物量与干、枝、叶各组分生物量之间的相容性问题,各组分生物量模型的确定系数都在0.8以上,地上生物量模型的确定系数最高,树叶生物量模型的确定系数最低;使用相同的参数估计算法,2种结构的相容性生物量拟合效果差异不大;对比3种参数估计算法,采用二阶最小二乘法和三阶最小二乘法拟合的相容性生物量模型的参数估计值和评价指标是一致的,而与普通最小二乘法差别较大,但使用普通最小二乘法的拟合精度更高,且计算过程更简单。【结论】鉴于林业实践中通常以计算地上生物量为主要目的,利用基于普通最小二乘法得到的比例总量直接控制模型,可以以较高的预估精度直接计算出地上生物量,具有良好应用前景。

关键词：最小二乘法相容性生物量模型青冈栎次生林比例总量直接控制代数和控制