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Water pumping analysis and experimental validation of beach well infiltration intake system in a seawatersource heat pump system

Huan ZHANG,Shu LIU,Xuejing ZHENG,Gaofeng CHEN

《能源前沿(英文)》 2015年 第9卷 第3期   页码 335-342 doi: 10.1007/s11708-015-0365-7

摘要: Based on energy conservation equation and Darcy’s law, a model of beach well infiltration intake system applied in a seawater source heat pump system was established. The model consists of the seawater seepage and the heat transfer process. A porous medium model in a software named FLUENT was applied to simulate the seepage and the heat transfer process. This model was also validated by field experiment conducted on the seashore in Tianjin, China. The maximum relative error between simulation results and experimental results was 2.1% (less than 5%), which was acceptable in engineering application. The porosity and coefficient of thermal conductivity of the aquifer soil were determined to be 0.49 W/(m·K) and 1.46 W/(m·K), respectively in the simulation. In addition, the influencing factors of pumping water of beach well were also analyzed. The pumping water was found to increase when the distance between the beach well and the impervious boundary becomes longer, when the distance between the beach well and the supplying water source shortens, when the diameter of the beach well enlarges, and the drawdown enlarges.

关键词: water pumping analysis     experimental validation     infiltration intake system     seawater source heat pump    

Estimation and optimization operation in dealing with inflow and infiltration of a hybrid sewerage system

Mingkai Zhang, He Jing, Yanchen Liu, Hanchang Shi

《环境科学与工程前沿(英文)》 2017年 第11卷 第2期 doi: 10.1007/s11783-017-0912-z

摘要: Inflow and infiltration of a sewage system was estimated by synthetic model. Homological feature of catchments was recognized by self-organizing map. Occurrence risk index was proposed to assess catchment operation problem. Optimal strategy was used to reduce surcharge events and improve effluent quality. Inflow and infiltration (I/I) are serious problems in hybrid sewerage systems. Limited sewerage information impedes the estimation accuracy of I/I for each system catchment because of its unknown distribution. A new method proposed to deal with I/I of a large-scale hybrid sewerage system with limited infrastructure facility data is presented in this study. The catchment of representative pump stations was adopted to demonstrate the homological catchments that have similar wastewater fluctuation characteristics. Homological catchments were clustered using the self-organizing map (SOM) analysis based on long-term daily flow records of 50 pumping stations. An assessment index was applied to describe the I/I and overflow risk of representative pump stations in the catchment based on the hourly wastewater quality and quantity data. The potential operational strategy of homological catchments was generated by the assessment index of representative pump stations. The simulation results of the potential operational strategy indicated that the optimized operation strategy could reduce surcharge events and significantly improve the quality of wastewater treatment plant effluent.

关键词: Hybrid sewerage system     Wastewater treatment plant     Optimization operation     Inflow     Infiltration    

J-shaped association between dietary zinc intake and new-onset hypertension: a nationwide cohort study

《医学前沿(英文)》 2023年 第17卷 第1期   页码 156-164 doi: 10.1007/s11684-022-0932-3

摘要: We aimed to investigate the relationship of dietary zinc intake with new-onset hypertension among Chinese adults. A total of 12,177 participants who were free of hypertension at baseline from the China Health and Nutrition Survey were included. Dietary intake was assessed by three consecutive 24-h dietary recalls combined with a household food inventory. Participants with systolic blood pressure 140 mmHg or diastolic blood pressure 90 mmHg or diagnosed by a physician or under antihypertensive treatment during the follow-up were defined as having new-onset hypertension. During a median follow-up duration of 6.1 years, 4269 participants developed new-onset hypertension. Overall, the association between dietary zinc intake and new-onset hypertension followed a J-shape (P for non-linearity < 0.001). The risk of new-onset hypertension significantly decreased with the increment of dietary zinc intake (per mg/day: hazard ratio (HR) 0.93; 95% confidence interval (CI) 0.88–0.98) in participants with zinc intake < 10.9 mg/day, and increased with the increment of zinc intake (per mg/day: HR 1.14; 95% CI 1.11–1.16) in participants with zinc intake 10.9 mg/day. In conclusion, there was a J-shaped association between dietary zinc intake and new-onset hypertension in general Chinese adults, with an inflection point at about 10.9 mg/day.

关键词: dietary zinc intake     new-onset hypertension     general population     CHNS    

Effect of mulching with maize straw on water infiltration and soil loss at different initial soil moistures

Yifu ZHANG,Hongwen LI,Jin HE,Qingjie WANG,Ying CHEN,Wanzhi CHEN,Shaochun MA

《农业科学与工程前沿(英文)》 2016年 第3卷 第2期   页码 161-170 doi: 10.15302/J-FASE-2016104

摘要: Mulching and soil water content (SWC) have a significant impact on soil erosion, and this study investigated the effect of straw mulching on water infiltration and soil loss under different initial SWC treatments in a rainfall simulation experiment conducted in northern China. Increasing initial SWC can decrease soil infiltration and increase soil loss. During an 80 mm rainfall event (80 mm·h for 60 min), 8%, 12% and 16% initial SWC treatments decreased cumulative infiltration by 8.7%, 42.5% and 58.1%, and increased total sediment yield by 44, 146 and 315 g, respectively, compared to 4% initial SWC. However, in all the straw mulching treatments, there was no significant difference in stable infiltration rate between the different initial SWC treatments. For all initial SWC treatments, straw mulching of 30% or more significantly enhanced water infiltration by over 31% and reduced soil loss by over 49%, compared to the unmulched treatment. Taking into consideration the performance of no-till planters, a maize straw mulching rate of 30% to 60% (1400–3100 kg·hm ) is recommended for the conservation of water and soil in northern China.

关键词: infiltration     initial soil water content     rainfall simulation     soil loss     straw mulching    

Influence of infiltration on energy consumption of a winery building

Hejiang SUN, Qingxia YANG

《能源前沿(英文)》 2014年 第8卷 第1期   页码 110-118 doi: 10.1007/s11708-013-0293-3

摘要: With the wide use of light steel structure in industrial buildings, some problems such as air leakage, water dripping and condensation and so forth occur during the construction and operation phases. Through the onsite testing of a winery building in Huailai County, Hebei Province in China, the influence of infiltration on energy consumption in industrial buildings was studied. The pressurization test method and moisture condensation method were used to test the infiltration rates. The results show that the winery building is twice as leaky as normal Chinese buildings and five times as leaky as Canadian buildings. The energy use simulation demonstrates that the reduction of the infiltration rate of the exterior rooms to 1/3 and the interior rooms to 1/2 could help decrease a total energy consumption of approximately 20% and reduce a total energy cost of approximately $ 225000. Therefore, it has a great potential to reduce the energy consumption in this type of buildings. Enforcement of the appropriate design, construction and installation would play a significant role in improving the overall performance of the building.

关键词: industrial building     air change rate     pressurization test method     moisture condensation method     energy cost    

Optimization design of anti-seismic engineering measures for intake tower based on non-dominated sorting

《结构与土木工程前沿(英文)》   页码 1428-1441 doi: 10.1007/s11709-023-0998-2

摘要: High-rise intake towers in high-intensity seismic areas are prone to structural safety problems under vibration. Therefore, effective and low-cost anti-seismic engineering measures must be designed for protection. An intake tower in northwest China was considered the research object, and its natural vibration characteristics and dynamic response were first analyzed using the mode decomposition response spectrum method based on a three-dimensional finite element model. The non-dominated sorting genetic algorithm-II (NSGA-II) was adopted to optimize the anti-seismic scheme combination by comprehensively considering the dynamic tower response and variable project cost. Finally, the rationality of the original intake tower antiseismic design scheme was evaluated according to the obtained optimal solution set, and recommendations for improvement were proposed. The method adopted in this study may provide significant references for designing anti-seismic measures for high-rise structures such as intake towers located in high-intensity earthquake areas.

关键词: intake tower     NSGA-II     mode decomposition response spectrum method     anti-seismic engineering measures     optimization design     variable project cost    

Assessment on contaminations in sediments of an intake and the inflow canals in Taihu Lake, China

Xiaolong WANG,Shiming DING,Qi ZHANG,Weiping HU

《环境科学与工程前沿(英文)》 2015年 第9卷 第4期   页码 665-674 doi: 10.1007/s11783-014-0701-x

摘要: As the second largest freshwater lake in China, Taihu Lake provides water supply to approximately 32 million inhabitants around the lake. However, dramatically increased pollution has threatened the safety of drinking water supply in recent years. In the present study, we investigated the contaminations of nutrients and heavy metals in the sediments of an intake and inflow canals in Gonghu Bay, Taihu Lake. Moreover, we also examined the impact of human activities on spatial distribution characteristics of contaminations. Our results showed that the intake presented relatively lower concentrations of phosphorus and nitrogen compared with inflow canals. However, the concentrations of Cr, Ni, Cu, Zn and Pb in the sediments of the intake exceeded the lowest effect level (LEL) values, indicating a potential risk to drinking water resource. In addition, the concentrations of Ni in the sediments of Tianji Canal and Jinshu Canal exceeded the severe effect level (SEL) value. More importantly, the concentrations of Cu in the sediments of Tianji Canal exceeded three times of the SEL value. Multivariate statistical analysis confirmed that the domestic sewage primarily contributed to the nutrient accumulation, and the leakage of electronic trash dominated the enrichment of metals in the sediments. Taken together, more effort should be made to ensure the security of water resources in Taihu Lake, especially for the treatment of domestic sewage and industrial wastewater.

关键词: drinking water resource     nutrients     heavy metals     sediments     Taihu Lake    

The removal of trimethoprim and sulfamethoxazole by a high infiltration rate artificial composite soiltreatment system

Qinqin Liu,Miao Li,Fawang Zhang,Hechun Yu,Quan Zhang,Xiang Liu

《环境科学与工程前沿(英文)》 2017年 第11卷 第2期 doi: 10.1007/s11783-017-0920-z

摘要: Artificial composite soil treatment system with the high infiltration rate (1.394 m·d ) had a good removal efficiency of TMP (80%–90%) and SMX (60%–70%). The removal mechanism of TMP and SMX was mainly sorption and was related with hydrogeochemical process. Sulfamethoxzole (SMX) and trimethoprim (TMP), two combined-using sulfonamide antibiotics, have gained increasing attention in the surface water, groundwater and the drinking water because of the ecological risk. The removal of TMP and SMX by artificial composite soil treatment system (ACST) with different infiltration rates was systematically investigated using K , Na , Ca , Mg hydrogeochemical indexes. Batch experiments showed that the sorption onto the low-cost and commercially available clay ceramsites was effective for the removal of SMX and TMP from water. The column with more silty clay at high infiltration rate (1.394 m·d ) had removal rates of 80% to 90% for TMP and 60% to 70% for SMX. High SMX and TMP removal rates had a higher effluent concentration of K , Ca and Mg and had a lower effluent Na concentration. Removal was strongly related to sorption. The results showed that the removal of SMX and TMP was related to hydrogeochemical processes. In this study, ACST is determined to be applicable to the drinking water plants.

关键词: Trimethoprim     Sulfamethoxazole     Artificial composite soil treatment     Hydrogeochemical processes     Ion exchange    

c-Fos expression in rat brainstem following intake of sucrose or saccharin

Ke Chen, Jianqun Yan, Jinrong Li, Bo Lv, Xiaolin Zhao

《医学前沿(英文)》 2011年 第5卷 第3期   页码 294-301 doi: 10.1007/s11684-011-0144-8

摘要: To examine whether the activation of brainstem neurons during intake of a sweet tastant is due to orosensory signals or post-ingestive factors, we compared the distribution of c-Fos-like immunoreactivity (c-FLI) in the nucleus of the solitary tract (NST) and parabrachial nucleus (PBN) of brainstem following ingestion of 0.25 M sucrose or 0.005 M saccharin solutions. Immunopositive neurons were localized mainly in the middle zone of the PBN and four rostral-caudal subregions of the NST. Intake of sucrose increased the number of FLI neurons in almost every subnucleus of the PBN (F = 7.610, = 0.023), in addition to the caudal NST at the level of the area postrema (F = 10.777, = 0.003) and the NST intermediate zone (F = 7.193, = 0.014). No significant increase in the number of c-Fos positive neurons was detected in response to saccharin ingestion, although there was a trend towards a modest increase in a few select NST and PBN nuclei. These results suggest that the PBN and NST may be involved in sweet taste perception and modulation of sweet tastant intake, but the significantly enhanced intensity of Fos expression induced by sucrose indicates that PBN/NST neuronal activity is driven by the integrated effects of sweet taste sensation and post-ingestive signals.

关键词: c-Fos     parabrachial     the nucleus of the solitary tract     sweet tastant     rat    

Association of maternal depression with dietary intake, growth, and development of preterm infants: a

Han Wang, Hong Zhou, Yan Zhang, Yan Wang, Jing Sun

《医学前沿(英文)》 2018年 第12卷 第5期   页码 533-541 doi: 10.1007/s11684-017-0591-y

摘要:

This study aimed to explore the association of maternal depression with nutrient intake, growth, and development of preterm infants. A cohort study of 201 infants was conducted in Beijing. Based on the gestational age of an infant and status of the mother, the infants were divided into four groups: non-depression-fullterm (64), non-depression-preterm (70), depression-fullterm (36), and depression-preterm (31). Data on sociodemographic characteristics, nutritional intake, growth, and developmental status of children at 8 months (corrected ages) were collected using a quantitative questionnaire, a 24-Hour Dietary Recall, anthropometric measurements, and the Bayley-III scale. A multivariate analysis was used to evaluate the effects of maternal depression and preterm birth on infant growth and development. The energy, protein, and carbohydrate intake in the depression group was lower than the recommended amounts. The depression preterm groups indicated the lowest Z-scores for length and weight and the lowest Bayley-III scores. Preterm infants of depressed mothers are at high risks of poor growth and development delay.

关键词: maternal depression     preterm     infant     nutrition     growth     development    

Soil-water interaction in unsaturated expansive soil slopes

ZHAN Liangtong

《结构与土木工程前沿(英文)》 2007年 第1卷 第2期   页码 198-204 doi: 10.1007/s11709-007-0023-1

摘要: The intensive soil-water interaction in unsaturated expansive soil is one of the major reasons for slope failures. In this paper, the soil-water interaction is investigated with the full-scale field inspection of rainwater infiltration and comprehensive experiments, including wetting-induced softening tests, swelling, and shrinkage tests. It is demonstrated that the soil-water interaction induced by seasonal wetting-drying cycles is very complex, and it involves coupled effects among the changes in water content, suction, stress, deformation and shear strength. In addition, the abundant cracks in the expansive soil play an important role in the soil-water interaction. The cracks disintegrate the soil mass, and more importantly, provide easy pathways for rainfall infiltration. Infiltration of rainwater not only results in wetting-induced softening of the shallow unsaturated soil layers, but also leads to the increase of horizontal stress. The increase of horizontal stress may lead to a local passive failure. The seasonal wetting-drying cycles tend to result in a down-slope creeping of the shallow soil layer, which leads to progressive slope failure.

关键词: strength     intensive soil-water     comprehensive     Infiltration     wetting-induced softening    

水电站叠梁门多层取水下泄水温公式

高学平,陈弘,宋慧芳

《中国工程科学》 2011年 第13卷 第12期   页码 63-67

摘要:

对于温度成层型水库,水电站进水口分层取水方式通常被采用,目的是有选择地取用水库的不同层水体,减免下泄低温水对下游河流环境的负面影响。目前缺乏简单实用的分层取水下泄水温的预测公式。笔者针对糯扎渡水电站工程,试验模拟水库水温分布,量测下泄水温;依据大量的试验数据,建立下泄水温预测公式;所提出的公式得到了锦屏一级电站下泄水温试验数据的验证。

关键词: 温度成层型水库     水电站进水口     叠梁门     下泄水温公式     模型试验    

Flow and mass balance analysis of eco-bio infiltration system

Marla C. MANIQUIZ, Lee-Hyung KIM, Soyoung LEE, Jiyeon CHOI

《环境科学与工程前沿(英文)》 2012年 第6卷 第5期   页码 612-619 doi: 10.1007/s11783-012-0448-1

摘要: A structured stormwater infiltration system was developed and constructed at a university campus and monitoring of storm events was performed during a one-year operation period. The flow and pollutant mass balances were analyzed and the overall efficiency of the system was assessed. While significant positive correlations were observed among rainfall, runoff and discharge volume ( = 0.93-0.99; <0.05), there was no significant correlations existed between rainfall, runoff, discharge volume and pollutant load. The system was more effective in reducing the runoff volume by more than 50% for small storm events but the difference between the runoff and discharge volume was significant even with rainfall greater than 10 mm. Results showed that the pollutant reduction rates were higher compared to the runoff volume reduction. Average pollutant reduction rates were in the range of 72% to 90% with coefficient of variation between 0.10 and 0.46. Comparable with runoff reduction, the system was more effective in reducing the pollutant load for small storm events, in the range of 80% to 100% for rainfall between 0 and 10 mm; while 65% to 80% for rainfall between 10 and 20 mm. Among the pollutant parameters, particulate matters was highly reduced by the system achieving only a maximum of 25% discharge load even after the entire runoff was completely discharged. The findings have proven the capability of the system as a tool in stormwater management achieving both flow reduction and water quality improvement.

关键词: best management practice     flow balance     low impact development     mass balance     nonpoint source     stormwater runoff    

The development of roadside green swales in the Chinese Sponge City Program: Challenges and opportunities

《工程管理前沿(英文)》   页码 566-581 doi: 10.1007/s42524-023-0267-z

摘要: Roadside green swales have emerged as popular stormwater management infrastructure in urban areas, serving to mitigate stormwater pollution and reduce urban surface water discharge. However, there is a limited understanding of the various types, structures, and functions of swales, as well as the potential challenges they may face in the future. In recent years, China has witnessed a surge in the adoption of roadside green swales, especially as part of the prestigious Sponge City Program (SCP). These green swales play a crucial role in controlling stormwater pollution and conserving urban water resources by effectively removing runoff pollutants, including suspended solids, nitrogen, and phosphorus. This review critically examines recent research findings, identifies key knowledge gaps, and presents future recommendations for designing green swales for effective stormwater management, with a particular emphasis on ongoing major Chinese infrastructure projects. Despite the growing global interest in bioswales and their significance in urban development, China’s current classification of such features lacks a clear definition or specific consideration of bioswales. Furthermore, policymakers have often underestimated the adverse environmental effects of road networks, as reflected in existing laws and planning documents. This review argues that the construction and maintenance of roadside green swales should be primarily based on three critical factors: Well-thought-out road planning, suitable construction conditions, and sustainable long-term funding. The integration of quantitative environmental standards into road planning is essential to effectively address the challenge of pollution from rainfall runoff. To combat pollution associated with roads, a comprehensive assessment of potential pollution loadings should be carried out, guiding the appropriate design and construction of green swales, with a particular focus on addressing the phenomenon of first flush. One of the major challenges faced in sustaining funds for ongoing maintenance after swale construction. To address this issue, the implementation of a green finance platform is proposed. Such a platform would help ensure the availability of funds for continuous maintenance, thus maximizing the long-term effectiveness of green swales in stormwater management. Ultimately, the findings of this review aim to assist municipal governments in enhancing and implementing future urban road designs and SCP developments, incorporating effective green swale strategies.

关键词: grass swale     infiltration swale     bioswale     wet swale     sponge city    

Astragaloside IV suppresses post-ischemic natural killer cell infiltration and activation in the brain

Baokai Dou, Shichun Li, Luyao Wei, Lixin Wang, Shiguo Zhu, Zhengtao Wang, Zunji Ke, Kaixian Chen, Zhifei Wang

《医学前沿(英文)》 2021年 第15卷 第1期   页码 79-90 doi: 10.1007/s11684-020-0783-8

摘要: Natural killer (NK) cells, a type of cytotoxic lymphocytes, can infiltrate into ischemic brain and exacerbate neuronal cell death. Astragaloside IV (ASIV) is the major bioactive ingredient of , a Chinese herbal medicine, and possesses potent immunomodulatory and neuroprotective properties. This study investigated the effects of ASIV on post-ischemic brain infiltration and activation of NK cells. ASIV reduced brain infarction and alleviated functional deficits in MCAO rats, and these beneficial effects persisted for at least 7 days. Abundant NK cells infiltrated into the ischemic hemisphere on day 1 after brain ischemia, and this infiltration was suppressed by ASIV. Strikingly, ASIV reversed NK cell deficiency in the spleen and blood after brain ischemia. ASIV inhibited astrocyte-derived CCL2 upregulation and reduced CCR2 NK cell levels in the ischemic brain. Meanwhile, ASIV attenuated NK cell activating receptor NKG2D levels and reduced interferon-γ production. ASIV restored acetylation of histone H3 and the p65 subunit of nuclear factor-κB in the ischemic brain, suggesting inhibition of histone deacetylase (HDAC). Simultaneously, ASIV prevented p65 nuclear translocation. The effects of ASIV on reducing CCL2 production, restoring acetylated p65 levels and preventing p65 nuclear translocation were mimicked by valproate, an HDAC inhibitor, in astrocytes subjected to oxygen-glucose deprivation. Our findings suggest that ASIV inhibits post-ischemic NK cell brain infiltration and activation and reverses NK cell deficiency in the periphery, which together contribute to the beneficial effects of ASIV against brain ischemia. Furthermore, ASIV’s effects on suppressing NK cell brain infiltration and activation may involve HDAC inhibition.

关键词: astragaloside IV     brain ischemia     natural killer cells     histone deacetylase     nuclear factor-κB    

标题 作者 时间 类型 操作

Water pumping analysis and experimental validation of beach well infiltration intake system in a seawatersource heat pump system

Huan ZHANG,Shu LIU,Xuejing ZHENG,Gaofeng CHEN

期刊论文

Estimation and optimization operation in dealing with inflow and infiltration of a hybrid sewerage system

Mingkai Zhang, He Jing, Yanchen Liu, Hanchang Shi

期刊论文

J-shaped association between dietary zinc intake and new-onset hypertension: a nationwide cohort study

期刊论文

Effect of mulching with maize straw on water infiltration and soil loss at different initial soil moistures

Yifu ZHANG,Hongwen LI,Jin HE,Qingjie WANG,Ying CHEN,Wanzhi CHEN,Shaochun MA

期刊论文

Influence of infiltration on energy consumption of a winery building

Hejiang SUN, Qingxia YANG

期刊论文

Optimization design of anti-seismic engineering measures for intake tower based on non-dominated sorting

期刊论文

Assessment on contaminations in sediments of an intake and the inflow canals in Taihu Lake, China

Xiaolong WANG,Shiming DING,Qi ZHANG,Weiping HU

期刊论文

The removal of trimethoprim and sulfamethoxazole by a high infiltration rate artificial composite soiltreatment system

Qinqin Liu,Miao Li,Fawang Zhang,Hechun Yu,Quan Zhang,Xiang Liu

期刊论文

c-Fos expression in rat brainstem following intake of sucrose or saccharin

Ke Chen, Jianqun Yan, Jinrong Li, Bo Lv, Xiaolin Zhao

期刊论文

Association of maternal depression with dietary intake, growth, and development of preterm infants: a

Han Wang, Hong Zhou, Yan Zhang, Yan Wang, Jing Sun

期刊论文

Soil-water interaction in unsaturated expansive soil slopes

ZHAN Liangtong

期刊论文

水电站叠梁门多层取水下泄水温公式

高学平,陈弘,宋慧芳

期刊论文

Flow and mass balance analysis of eco-bio infiltration system

Marla C. MANIQUIZ, Lee-Hyung KIM, Soyoung LEE, Jiyeon CHOI

期刊论文

The development of roadside green swales in the Chinese Sponge City Program: Challenges and opportunities

期刊论文

Astragaloside IV suppresses post-ischemic natural killer cell infiltration and activation in the brain

Baokai Dou, Shichun Li, Luyao Wei, Lixin Wang, Shiguo Zhu, Zhengtao Wang, Zunji Ke, Kaixian Chen, Zhifei Wang

期刊论文