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Automatic control strategy for step feed anoxic/aerobic biological nitrogen removal process

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Journal of Environmental Sciences 2005年第3期17卷 457-459页

作者： ZHUGui-bing PENGYong-zhen WUShu-yun wangshu-ying SchoolofMunicipalandEnvironmentalEngineering HarbinInstituteofTechnologyHarbin150090China KeyLaboratoryofBeijingWaterQualityScienceandWaterEnvironmentRecoveryEngineering BeijingPolytechnicUniversityBeijing100022China

Control of sludge age and mixed liquid suspended solids concentration in the activated sludge process is critical for ensuring effective wastewater treatment. A nonlinear dynamic model for a step-feed activated sludge process was developed in this study. The system is based on the control of the sludge age and mixed liquor suspended solids in the aerator of last stage by adjusting the sludge recycle and wastage flow rates respectively. The simulation results showed that the sludge age remained nearly constant at a value of 16 d in the variation of the influent characteristics. The mixed liquor suspended solids in the aerator of last stage were also maintained to a desired value of 2500 g/m3 by adjusting wastage flow rates.

关键词： wastewater treatment sludge age control modeling and simulation step-feed process

Nitrogen removal influence factors in A/O process and decision trees for nitrification/denitrification system

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Journal of Environmental Sciences 2004年第6期16卷 901-907页

作者： MAYong PENGYong-zhen wangshu-ying WANGXiao-lian SchoolofMunicipalandEnvironmentalEngineering HarbinInstituteofTechnologyHarbin150090China DepartmentofEnvironmentalEngineering BeijingUniversityofTechnologyBeijing100022China

In order to improve nitrogen removal in anoxic/oxic(A/O) process effectively for treating domestic wastewaters, the influence factors, DO(dissolved oxygen), nitrate recirculation, sludge recycle, SRT(solids residence time), influent COD/TN and HRT(hydraulic retention time) were studied. Results indicated that it was possible to increase nitrogen removal by using corresponding control strategies, such as, adjusting the DO set point according to effluent ammonia concentration; manipulating nitrate recirculation flow according to nitrate concentration at the end of anoxic zone. Based on the experiments results, a knowledge-based approach for supervision of the nitrogen removal problems was considered, and decision trees for diagnosing nitrification and denitrification problems were built and successfully applied to A/O process.

关键词： A/O process nitrification denitrification nitrogen removal decision trees

Effect of carbon source and nitrate concentration on denitrifying phosphorus removal by DPB sludge

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Journal of Environmental Sciences 2004年第4期16卷 548-552页

作者： WANGYa-yi PENGYong-zhen wangshu-ying PANMian-li CollegeofMunicipalandEnvironmentalEngineering HarbinInstituteofTechnologyHarbin150008China CollegeofEnvironmentandEnergyEngineering BeijingUniversityofTechnologyBeijing100022China HangzhouHuadongGene-TechnologyInstitute Hangzhou310000China

Effect of added carbon source and nitrate concentration on the denitrifying phosphorus removal by DPB sludge was systematically studied using batch experiments, at the same time the variation of ORP was investigated. Results showed that the denitrifying and phosphorus uptake rate in anoxic phase increased with the high initial anaerobic carbon source addition. However once the initial COD concentration reached a certain level, which was in excess to the PHB saturation of poly-P bacteria, residual COD carried over to anoxic phase inhibited the subsequent denitrifying phosphorus uptake. Simultaneously, phosphate uptake continued until all nitrate was removed, following a slow endogenous release of phosphate. High nitrate concentration in anoxic phase increased the initial denitrifying phosphorus rate. Once the nitrate was exhausted, phosphate uptake changed to release. Moreover, the time of this turning point occurred later with the higher nitrate addition. On the other hand, through on-line monitoring the variation of the ORP with different initial COD concentration, it was found ORP could be used as a control parameter for phosphorus release, but it is impossible to utilize ORP for controlling the denitrificaion and anoxic phosphorus uptake operations.

关键词： biological phosphorus removal carbon source nitrate ORP denitrifying phosphorus removal bacteria (DPB) anaerobic-anoxic processes

Alternating shortcut nitrification-denitrification for nitrogen removal from soybean wastewater by SBR with real-time control

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Journal of Environmental Sciences 2004年第3期16卷 380-383页

作者： wangshu-ying GAODa-wen PENGYong-zhen WANGPeng YANGQing DepartmentofEnvironmentalEngineering BeijingPolytechnicUniversityBeijing100022China CollegeofForestResourcesandEnvironment NortheastForestryUniversityHarbin150040China. SchoolofMunicipal＆EnvironmentalEngineering HarbinInstituteofTechnologyHarbin150090China

A novel treating technology for nitrogen removal from soybean wastewater was studied. The process for nitrogen removal was achieved by alternating aeration and mixing, combined with real\|time control strategies. Results showed that the COD and total nitrogen removal rates are more than 90% and 92% at COD and total nitrogen loads of 1\^0-1\^2 kg COD/(kgMLSS·d) and 0\^20-0\^27 kg TN/(kgMLSS·d), respectively. In addition, it could improve sludge settling property. SVI value is less than 70 g/ml during the whole cycles. The method not only may be adapted to treat soybean wastewater with high nitrogen, but also may be applied to treat other high nitrogen wastewater.

关键词： real-time shortcut nitrification-denitrification ORP pH SBR

Study on Flying Behavior of Tiphia popilliavora Rohwer in Two Types of Inter-Cropping Fields

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Agricultural Sciences in China 2003年第6期2卷 639-646页

作者： CHENHong-yin CHENChang-feng wangshu-ying LUOYi-zhen McDonaldRC Sino-AmericanBiologicalControlLaboratory ChineseAcademyofAgriculturalSciencesBeijing100081P.R.China InstituteofPlantProtection ShandongAcademyofAgriculturalSciencesJinang50100P.R.China NorthCarolinaDepartmentofAgriculture RaleighNC27611U.S.A.

A study was conducted in corn-peanut and sweet potato-peanut fields on the flying behavior of the white grub parasitoid Tiphia popilliavora Rohwer wasps. Observation on the first three times of flying, after the wasps being released. revealed that the first flying was an escape style and not showed preference to land on any special crops. 81. 82% wasps landed on corn leaves at the second flying but stayed for just about 3 min. In the sweet potato-peanut field, 51.43% wasps landed on sweet potato in contrast with 48.57% landed on peanuts and in the afternoon 33. 53% on sweet potato compared with 76.4% landed on peanut field. Majority preferred landing on peanut field on the third flying in both type fields of inter-cropping. Behavior of flying was different between morning and afternoon. The time length between two flies showed that wasps were more active in the morning than in the afternoon.

关键词： Tiphia wasps Fly Preference

Knockdown of RCN1 contributes to the apoptosis of colorectal cancer via regulating IP3R1

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BIOCELL 2024年第5期48卷 835-845页

作者： XUAN SHI YUFEN WANG CHENYU LI wangshu FU XINYUE ZHANG AIXIA GONG Department of Gastroenterology The First Affiliated Hospital of Dalian Medical UniversityDalianChina Department of Gastroenterology The First Affiliated Hospital of Jinzhou Medical UniversityJinzhouChina The First Clinical College Dalian Medical UniversityDalianChina

Background:The incidence of colorectal cancer(CRC)has been increasing in recent years.Thus,the discovery of factors that can assist in alleviating CRC is urgently warranted.Methods:To identify a potential factor involved in the development of CRC,we screened the upregulated genes in tumor tissues through four datasets from an online database.The expression of reticulocalbin 1(RCN1),a Ca2+-binding protein,was upregulated in the four datasets.Based on loss-offunction experiments,the effect of RCN1 on cell viability was assessed by Cell Counting Kit-8(CCK-8)assay.The regulatory effect of RCN1 on apoptosis was evaluated through Annexin V-fluorescein 5-isothiocyanate(FITC)/propidium iodide(PI)staining assay and terminal deoxynucleotidyl transferase-mediated dUTP nick-end labeling(TUNEL)assay in RKO and SW480 cells.Activation of endoplasmic reticulum(ER)stress signaling pathways was confirmed by estimating the phosphorylation and expression of PRKR-like ER kinase(PERK),inositol-requiring kinase-1(IRE1),transcription factor 6(ACT6),and CCAAT/enhancer-binding protein-homologous protein(CHOP).The intracellular Ca2+homeostasis regulated by RCN1 was determined through the detection of Ca2+concentration and mitochondrial membrane potential(MMP)measurement.Moreover,whether inositol 1,4,5-trisphosphate receptor type 1(IP3R1)was involved in the regulation of RCN1 in CRC was verified through the depletion of IP3R1 in RKO cells.Results:Knockdown of RCN1 reduced cell viability and facilitated apoptosis in RKO and SW480 cells.Phosphorylation of PERK and IRE1,activation of ATF6,and upregulation of CHOP were induced by the absence of RCN1,suggesting that the unfolded protein response(UPR)was activated in CRC cells.The concentration of Ca2+in mitochondria was increased after RCN1 depletion,followed by reduction in the MMP and release of cytochrome c from mitochondria to the cytoplasm in RKO and SW480 cells.Moreover,it was demonstrated that IP3R1 mediates the effect of RCN1 on apoptosis induced by ER stress in CRC cells.The downregulat

关键词： Reticulocalbin 1 Unfolded protein response IP3R1 Colorectal cancer

Biohythane production from two-stage anaerobic digestion of food waste:A review

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Journal of Environmental Sciences 2024年第5期139卷 334-349页

作者： Xiaona An ying Xu Xiaohu Dai State Key Laboratory of Pollution Control and Resource Reuse School of Environmental Science and EngineeringTongji UniversityShanghai 200092China Shanghai Institute of Pollution Control and Ecological Security Shanghai 200092China

The biotransformation of food waste(FW)to bioenergy has attracted considerable research attention as a means to address the energy crisis and waste disposal problems.To this end,a promising technique is two-stage anaerobic digestion(TSAD),in which the FW is transformed to biohythane,a gaseous mixture of biomethane and biohydrogen.This review summarises the main characteristics of FW and describes the basic principle of TSAD.Moreover,the factors influencing the TSAD performance are identified,and an overview of the research status;economic aspects;and strategies such as pre-treatment,co-digestion,and regulation of microbial consortia to increase the biohythane yield from TSAD is provided.Additionally,the challenges and future considerations associated with the treatment of FW by TSAD are highlighted.This paper can provide valuable reference for the improvement and widespread implementation of TSAD-based FW treatment.

关键词： Two-stage anaerobic digestion(TSAD) Food waste(FW) Methane production Hydrogen production

Neighborhood predictors of short sleep duration and bedtime irregularity among children in the United States: results from the 2019-2020 National Surveyof Children's Health

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World Journal of Pediatrics 2024年第1期20卷 73-81页

作者： ying Dai Jianghong Liu School of Nursing University of Pennsylvania418 Curie Blvd.Room 426Claire M.Fagin HallPhiladelphiaPA19104-6096USA

Background Environmental factors may contribute to short sleep duration and irregular bedtime in children.Neighborhood factors and children's sleep duration and bedtime regularity remain a less investigated area.The aim of this study was to investigate the national and state-level proportions of children with short sleep duration and irregular bedtime and their neighborhood predictors.Methods A total of 67,598 children whose parents completed the National Survey of Children's Health in 2019-2020 were included in the analysis.Survey-weighted Poisson regression was used to explore the neighborhood predictors of children's short sleep duration and irregular bedtime.Results The prevalence of short sleep duration and irregular bedtime among children in the United States(US)was 34.6%[95%confidence interval(CI)=33.8%-35.4%]and 16.4%(95%CI=15.6%-17.2%)in 2019-2020,respectively.Safe neighborhoods,supportive neighborhoods,and neighborhoods with amenities were found to be protective factors against children's short sleep duration,with risk ratios ranging between 0.92 and 0.94,P<0.05.Neighborhoods with detracting elements were associated with an increased risk of short sleep duration[risk ratio(RR)=1.06,95%CI=1.00-1.12]and irregular bedtime(RR=1.15,95%CI=1.03-1.28).Child race/ethnicity moderated the relationship between neighborhood with amenities and short sleepduration.Conclusions Insufficient sleep duration and irregular bedtime were highly prevalent among US children.A favorable neighborhood environment can decrease children's risk of short sleep duration and irregular bedtime.Improving the neighborhood environment has implications for children's sleep health,especially for children from minority racial/ethnic groups.

关键词： Child National Survey of Children's Health Neighborhood.Sleep Social determinants of health

A Novel Method for Forecasting Freak Wave Occurrence in A Short Crested Coastal Sea

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China Ocean Engineering 2024年第1期38卷 104-116页

作者： WANG ying-guang State Key Laboratory of Ocean Engineering Shanghai Jiao Tong UniversityShanghai 200240China School of Ocean and Civil Engineering Shanghai Jiao Tong UniversityShanghai 200240China

In order to forecast the distribution of crest amplitudes and the occurrence of freak waves in a short crested coastal sea,a novel transformed linear simulation method is initially proposed in this paper.A Hermite transformation model expressed as a monotonic cubic polynomial serves as the foundation for the novel simulation technique.The wave crest amplitude exceedance probabilities of two sea states-one with a directional wave spectrum based on the measured wave elevation data at the Yura coast and the other with a typical directional JONSWAP wave spectrum-have been predicted using the novel simulation method that has been proposed.The likelihood that a particular critical wave crest amplitude will be exceeded is directly correlated with the probability that freak waves will occur.It is shown that the novel simulation approach suggested can provide predictions that are more precise than those obtained from the Rayleigh crest amplitude distribution model,the Jahns and Wheeler crest amplitude distribution model,or the conventional linear simulation method.This study also demonstrated that the nonlinear simulation method is less effective than the novel simulation method in terms of efficiency.

关键词： wave crest amplitude freak waves short crested sea transformed linear simulation