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Water quality characteristics along the course of the Huangpu River (China)

Journal of Environmental Sciences 2007年第10期19卷 1193-1198页

作者： YANG hong-jun SHEN zhe-min ZHANG Jin-ping WANG wen-hua School of Environmental Science and Engineering Shanghai Jiao Tong University Shanghai 200240 China Xuhui District Environmental Protection Bureau Shanghai 200030 China Shanghai Environmental Monitoring Center Shanghai 200030 China

Huangpu River is about 114.5 km from upriver Dianfeng to downriver Wusong, near the estuary of the Yangtze River. It plays a key role in supplying water for production, life, shipment and irrigation. With the industrial development, the pollution of the Huangpu River has become serious recently. The biological oxygen demand （BOD）, total nitrogen （TN）, total phosphorus （TP）, oil, phenol and suspended solids （SS） were lower in the upstream sites than in the downstream sites, indicating pollutants being input along its course. Water quality was the worst in the Yangpu site, near the center of Shanghai City. Dissolved oxygen （DO） content was less than 2 mg/L in the site of Yangpu in July. Among relations between thirteen characteristics, relations between BOD, DO, TN, TP, NH4^＋ -N, NO3^- -N and the count of total bacteria or Escherichia coli were significant and interdependent. Inner relationships between these main characteristics in the Huangpu River were studied. High nutrient concentration led to growth of microorganisms, including E. coli. Degradation of organic matters and respiration of bacteria made oxygen concentration decreased in the water body, and DO was a key factor for nitrification-denitrification process of nitrogen. In the Yangpu site, DO was decreased to less than 3.0 mg/L with BOD higher than 7.5 mg/L in May and July. Low DO concentration will decrease nitrification rate. Nitrification need at higher DO value than other organic substrate oxidation. Consequently, river water contains low NO3^- -N values with high amounts of TN and NH4^＋ -N there. This will block the self-purification of surface water, by decreasing the rate of nitrification-denitrification transformation process in the water body.

关键词： water quality ecological assessment Huangpu River nitrification

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Detecting slowly moving infrared targets using temporal filtering and association strategy

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Frontiers of Information Technology & Electronic Engineering 2016年第11期17卷 1176-1185页

作者： Jing-li GAO Cheng-lin wen zhe-jing BAO Mei-qin LIU College of Electrical Engineering Zhejiang UniversityHangzhou 310027China School of Automation Hangzhou Dianzi UniversityHangzhou 310018China College of Electrical Engineering Henan University of TechnologyZhengzhou 350001China College of Software Engineering Pingdingshan UniversityPingdingshan 467000China

The special characteristics of slowly moving infrared targets, such as containing only a few pixels,shapeless edge, low signal-to-clutter ratio, and low speed, make their detection rather difficult, especially when immersed in complex backgrounds. To cope with this problem, we propose an effective infrared target detection algorithm based on temporal target detection and association strategy. First, a temporal target detection model is developed to segment the interested targets. This model contains mainly three stages, i.e., temporal filtering,temporal target fusion, and cross-product filtering. Then a graph matching model is presented to associate the targets obtained at different times. The association relies on the motion characteristics and appearance of targets,and the association operation is performed many times to form continuous trajectories which can be used to help disambiguate targets from false alarms caused by random noise or clutter. Experimental results show that the proposed method can detect slowly moving infrared targets in complex backgrounds accurately and robustly, and has superior detection performance in comparison with several recent methods.

关键词： Temporal target detection Slowly moving targets Graph matching Target association

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Vertical and temporal distribution of nitrogen and phosphorus and relationship with their influencing factors in aquatic-terrestrial ecotone:a case study in Taihu Lake,China

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Journal of Environmental Sciences 2007年第6期19卷 689-695页

作者： YANG hong-jun SHEN zhe-min ZHU Song-he WANG wen-hua School of Environmental Science and Engineering Shanghai Jiao Tong University Shanghai 200240 China

Vertical and temporal distributions of N and P in soil solution in aquatic-terrestrial ecotone （ATE） of Taihu Lake were investigated, and the relations among N, P, ORP （oxidation reduction potential）, TOC, root system biomass and microorganism were studied. As a whole, significant declines in TN, NO3^--N, DON （dissolved organic nitrogen） and TP concentration in soil solution have occurred with increase of the depth, and reached their minima at 60 cm depth, except for NH4^＋-N, which increased with depth. The concentration of TP increased gradually from spring to winter in the topsoil, the maximum 0.08 mg/L presented in the winter while the minimum 0.03 mg/L in spring. In the deeper layer, the concentration value of TP fluctuated little. As for the NO3^--N, its seasonal variation was significant at 20 cm depth, its concentration increased gradually from spring to autumn, and decreased markedly in winter. Vertical and temporal distribution of DON is contrary to that of NO3^--N. The results also show that the variation of N and P in the percolate between adjacent layers is obviously different. The vertical variation ofTN, TP, NO3^--N, NH4^＋-N and DON is significant, of which the variation coefficient of NO3^--N along the depth reaches 100.23%, the highest; while the variation coefficient of DON is 41.14%, the smallest. The results of correlation analysis show that the concentration of nitrogen and phosphorus correlate significantly with TOC, ORP, root biomass and counts of nitrifying bacteria. Most nutrients altered much from 20 to 40 cm along the depth. however, DON changed more between 60 and 80 cm. Results show that soil of 0-60 cm depth is active rhizoplane, with strong capability to remove the nitrogen and phosphorus in ATE. It may suggest that there exists the optimum ecological efficiency in the depth of above 60 cm in reed wetland. This will be very significant for ecological restoration and reestablishment.

关键词： aquatic-terrestrial ecotone (ATE) soil percolate vertical and temporal distribution coefficient of variation ecological efficiency

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Recognition of mortar pumpability via computer vision and deep learning

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Journal of Electronic Science and Technology 2023年第3期21卷 73-81页

作者： Hao-zhe Feng hong-Yang Yu wen-Yong Wang wen-Xuan Wang Ming-Qian Du Research Institute Electronic Science and Technology University of Electronic Science and Technology of ChinaChengdu611731China School of Computer Science and Engineering University of Electronic Science and Technology of ChinaChengdu611731China The Second Research Institute of Civil Aviation Administration of China Chengdu610041China

The mortar pumpability is essential in the construction industry,which requires much labor to estimate manually and always causes material *** paper proposes an effective method by combining a 3-dimensional convolutional neural network(3D CNN)with a 2-dimensional convolutional long short-term memory network(ConvLSTM2D)to automatically classify the mortar *** results show that the proposed model has an accuracy rate of 100%with a fast convergence speed,based on the dataset organized by collecting the corresponding mortar image *** work demonstrates the feasibility of using computer vision and deep learning for mortar pumpability classification.

关键词： Classification Computer vision Deep learning Pumpability 2-dimensional convolutional long short-term memory network (ConvLSTM2D) 3-dimensional convolutional neural network(3D CNN)

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陀螺刀焦点剂量测量与分析

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中国医疗器械信息 2025年第1期31卷 65-68页

作者：刘伟曹文杰黎哲升江西同欣检测技术有限公司江西南昌330052

目的:研究陀螺刀焦点剂量的检测方法,为专业技术人员对陀螺刀焦点剂量检测提供参考。方法:利用头部和体部模体以及剂量仪搭配电离室探测器和半导体探测器对三家医院的GMX-Ⅰ型陀螺刀焦点剂量进行检测;通过不同探测器的检测结果作比对,... 详细信息

目的:研究陀螺刀焦点剂量的检测方法,为专业技术人员对陀螺刀焦点剂量检测提供参考。方法:利用头部和体部模体以及剂量仪搭配电离室探测器和半导体探测器对三家医院的GMX-Ⅰ型陀螺刀焦点剂量进行检测;通过不同探测器的检测结果作比对,分析探测器的适用性和检测方法的可行性。结果:在头部和体部治疗模式下:当准直器尺寸为30mm和45mm时,使用尖点电离室探测器和半导体探测器测得的焦点剂量与计划剂量偏差-3.88%~3.01%,符合标准要求;当准直器尺寸为6mm和12mm时,使用尖点电离室探测器测得的焦点剂量与计划剂量偏差-31.4%~-7.03%,超出标准要求,而使用半导体探测器测得的焦点剂量与计划剂量偏差-3.27%~2.70%,符合标准要求。结论:对陀螺刀焦点剂量的检测须根据准直器照射野尺寸选用合适的探测器,检测方法可行。

关键词：陀螺刀焦点剂量检测方法电离室探测器半导体探测器

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Microdeletions and vertical transmission of the Y-chromosome azoospermia factor region

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Asian Journal of Andrology 2023年第1期25卷 5-12页

作者： Chen-Yao Deng zhe Zhang wen-Hao Tang Hui Jiang Department of Urology Third Hospital of Peking UniversityBeijing 100089China Department of Andrology Third Hospital of Peking UniversityBeijing 100089China Department of Human Sperm Bank Third Hospital of Peking UniversityBeijing 100089China

Spermatogenesis is regulated by several Y chromosome-specific genes located in a specific region of the long arm of the Y chromosome,the azoospermia factor region(AZF).AZF microdeletions are the main structural chromosomal abnormalities that cause male *** reproductive technology(ART)has been used to overcome natural fertilization barriers,allowing infertile couples to have ***,these techniques increase the risk of vertical transmission of genetic *** widespread awareness of AZF microdeletions,the occurrence of de novo deletions and overexpression,as well as the expansion of AZF microdeletion vertical transmission,remains *** review summarizes the mechanism of AZF microdeletion and the function of the candidate genes in the AZF region and their corresponding clinical ***,vertical transmission cases of AZF microdeletions,the impact of vertical inheritance on male fertility,and the prospective direction of research in this field are also outlined.

关键词： azoospermia factor male infertility microdeletion vertical transmission

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A chiral aldehyde-induced tandem conjugated addition–lactamization reaction for constructing fully substituted pyroglutamic acids

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Organic Chemistry Frontiers 2022年第5期9卷 1422-1426页

作者： wen-zhe Wang Hao-Ran Shen Jian Liao Wei wen Qi-Xiang Guo Key Laboratory of Applied Chemistry of Chongqing Municipality School of Chemistry and Chemical EngineeringSouthwest UniversityChongqing400715China

A catalytic asymmetric tandem reaction including a chiral aldehyde catalyzed conjugated addition and an intramolecular lactamization is reported in this *** the optimal reaction conditions,various fully substituted pyroglutamic acids bearing three vicinal chiral centers were generated in good-to-excellent yields and stereoselectivities.A reasonable reaction mechanism is proposed to illustrate the observed stereoselective control results.

关键词： chiral substituted conjugated

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Advancements in diabetic retinopathy:Insights and future directions

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World Journal of Methodology 2025年第2期15卷 21-26页

作者： Chun-Yao Cheng wen-Rui Hao Tzu-Hurng Cheng Department of Ophthalmology Cathay General HospitalTaipei 10633TaiwanChina Division of Cardiology Department of Internal MedicineShuang Ho HospitalMinistry of Health and WelfareTaipei Medical UniversityNew Taipei 23561TaiwanChina Division of Cardiology Department of Internal MedicineSchool of MedicineCollege of MedicineTaipei Medical UniversityTaipei 11002TaiwanChina Department of Biochemistry School of MedicineCollege of MedicineChina Medical UniversityTaichung 404328TaiwanChina

This editorial discusses recent advancements and ongoing challenges in diabetic retinopathy,as reviewed by Morya et al in their comprehensive *** their review,Morya et al discussed the pathophysiology of diabetic retinopathy and explored novel treatment *** editorial highlights the importance of these advancements and emphasizes the need for continued research and innovation for the enhanced management of diabetic *** also reflects upon the implications of the authors’review findings for clinical practice and future research directions,underscoring the potential of emerging therapies for improving patient outcomes and providing a deeper understanding of disease mechanisms.

关键词： Diabetic retinopathy Pathophysiology Novel treatments Review analysis Clinical implications

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A new preparation technology of structural- gradient materials without a brittle transition zone in a Mn-Si-Cr-B bainitic cast steel

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China Foundry 2018年第4期15卷 283-290页

作者： yu-guang zhao zhe wang xiao-feng xu ming-zhe zhang wen-qiang jiang key laboratory of automobile of ministry of Education ＆school of Materials Science and Engineering Nanling Campusjilin UniversityNO.5988 Renmin streetchangchun 130025china

In the present work, a unique gradient cooling heat treatment process(GCHT) for a Mn-Si-Cr-B bainitic cast steel was developed, and microstructure and mechanical properties were examined by OM, SEM, EBSD and a uniaxial tensile test. The results showed that the structural-gradient-material(SGM) with a gradient microstructure from granular bainite to martensite was successfully produced, and it exhibited a good ductility(~13.8%) at one end and an excellent ultimate strength(~1,720 MPa) at the other end. In between the bainite and martensite, a transition region with a superior combination of tensile strength and ductility(1,700 MPa and 11.1%) was obtained, which is different from the normal knowledge of a brittle transition region. Moreover, through changing the gradient of cooling rate, the optimized SGM with a new gradient microstructure from pearlite to martensite showed a more stable structural gradient and an improved ductility(22.8%) at one end. The microstructure variation in the sample was mainly related to the carbon diffusion rate during heat treatment, and the diffusion rate could be controlled by regulating the cooling velocity. Therefore, the SGMs with different gradient microstructures could be designed to meet the needs of different properties. As a result, this work provides a new approach for preparation of the gradient structured steel, which has potential for practical application for dual-property automobile parts.

关键词： bainitic cast steel gradient cooling heat treatment structural-gradient-materials

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Use of graphene nanocomposites for air disinfection in dental clinics:A game-changer in infection control

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World Journal of Clinical Cases 2025年第8期13卷 57-62页

作者： Chun-Han Cheng wen-Rui Hao Tzu-Hurng Cheng Department of Medical Education Linkou Chang Gung Memorial HospitalTaoyuan 33305TaiwanChina Division of Cardiology Department of Internal MedicineShuang Ho HospitalMinistry of Health and WelfareTaipei Medical UniversityNew Taipei 23561TaiwanChina Division of Cardiology Department of Internal MedicineSchool of MedicineCollege of MedicineTaipei Medical UniversityTaipei 11002TaiwanChina Department of Biochemistry School of MedicineCollege of MedicineChina Medical UniversityTaichung 404328TaiwanChina

This manuscript features the promising findings of a study conducted by Ju et al,who used graphene nanocomposites for air disinfection in dental *** study demonstrated that,compared with conventional filters,graphene nanocom-posites substantially improved air quality and reduced microbial *** manuscript highlights the innovative application of graphene materials,emphasizing their potential to enhance dental clinic environments by minimizing secondary *** the basis of the unique antimicrobial properties of gra-phene and the original study’s rigorous methodology,we recommend using gra-phene nanocomposites in clinical settings to control airborne infections.

关键词： Graphene nanocomposites Air disinfection Dental clinics Antimicrobial properties Secondary pollution

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