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Nutrient transport following water transfer through the world's largest water diversion channel

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Journal of Environmental Sciences 2024年第1期135卷 703-714页

作者： Yuanhui cheng hong zhang Wei Yin State Key Laboratory of Environmental Aquatic Chemistry Research Center for Eco-Environmental SciencesChinese Academy of SciencesBeijing 100085 China Changjiang Water Resources Protection Institute Wuhan 430051China University of Chinese Academy of Sciences Beijing 100049China

Nutrient levels in the artificial channel constructed for the Middle Route Project are significant indicators of water quality safety and aquatic ecological integrity for this large,interbasin ***,the distribution and transport of nutrients along the channel were poorly *** on a time-series dataset as well as mass balance and material flow analysis methods,the water and nutrient transport fluxes in the Middle Route of the South-to-North Water Diversion Project were identified in this *** results indicate that the nutrient concentrations varied considerably with time,but there was no significant difference among the 30 stations of the main *** temperature difference was the major factor in the large fluctuations of water quality indicators over *** nutrient loadings varied with the water volume outputs from the main channel to the waterreceiving *** deposition was an important source of nutrients in the main channel,accounting for 9.13%,20.6%,and 0.635%of the nitrogen,phosphorus,and sulfur input from the Danjiangkou Reservoir,*** 2021,a net accumulation of 988 tons of N,29 tons of P,and 2,540 tons of S,respectively,were present in the main *** increase of these external and internal nutrient loadings would cause water quality fluctuation and deterioration in some local sections of the main *** study quantified the spatial and temporal patterns of nutrient transport in the Middle Route and revealed the ecological effects on the aquatic environment,assisting authorities on the project to develop effective water conservation strategies.

关键词： Nutrient transport Spatiotemporal patterns The Middle Route The South-to-North Diversion Project Hydro-ecological effects Water-receiving cities

The Figure and Dynamical Parameters of Io Inferred from Internal Structure Models

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Chinese Journal of Astronomy and Astrophysics 2001年第3期1卷 275-280页

作者： hongzhang cheng－Zhizhang DepartmentofAstronomy NanjingUniversityNanjing210093 DepartmentofAstronomy NanjingUniversityNanjing

The recent Galileo spacecraft explored Jupiter and its satellite system and provided us with new geodetic data. In order to discuss the dynamical parameters and secular tidal effect of Io, the theory of synchronous satellite is described in detail. Using the new geodetic data of Io, two sets of Io's internal structure models are constructed based on the asthenosphere assumption. The liberation parameters α,β,γ and dynamical flattening H are calculated for the models of Io. A comparison of Io with the Moon indicates that they are quite different in many characteristics in spite of the fact that they are approximately equal in mass and size and that they both orbit synchronously.

关键词： Io-synchronous orbit-dynamical parameters

Survey of antioxidant capacity and phenolic composition of blueberry,blackberry,and strawberry in Nanjing

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2012年第2期13卷 94-102页

作者： Wu-yang HUANG hong-cheng zhang Wen-xu LIU Chun-yang LI Department of Functional Food and Bioactive Compounds Institute of Farm Product ProcessingJiangsu Academy of Agricultural SciencesNanjing 210014China Bee Research Institute Chinese Academy of Agricultural SciencesBeijing 100093China College of Food Science and Technology Nanjing Agricultural UniversityNanjing 210095China

Berries are a good source of natural antioxidants. In the present study, the total antioxidant capacity and phenolic composition of three berry fruits （blueberry, blackberry, and strawberry） cultivated in Nanjing were investigated. Blueberry, with a Trolox equivalent antioxidant capacity （TEAC） value of 14.98 mmol Trolox/100 g dry weight （DW） exhibited the strongest total antioxidant capacity using both the 2,2-azinobis（3-ethylbenzothiazoline-6-sulfonic acid） diammonium salt （ABTS） and the 2,2-diphenyl-l-picrylhydrazyl （DPPH） methods. Blueberry also had the highest total phenolic content （TPC, 9.44 mg gallic acid/g DW）, total flavonoid content （TFC, 36.06 mg rutin/g DW）, and total anthocyanidin content （TAC, 24.38 mg catechin/g DW）. A preliminary analysis using high performance liquid chromatography （HPLC） showed that the blueberry, blackberry, and strawberry samples tested contained a range of phenolic acids （including gallic acid, protocatechuic acid, p-hydroxybenzoic acid, vanillic acid, caffeic acid, p-coumaric acid, ferulic acid, eUagic acid, and cinnamic acid） and various types of flavonoids （flavone： luteolin; flavonols： rutin, myricetin, quercetrin, and quercetin; flavanols： gallocatechin, epigallocatechin, catechin, and catechin gallate; anthocyanidins： malvidin-3-galactoside, malvidin-3-glucoside, and cyanidin）. In particular, the blueberries had high levels of proanthocyanidins and anthocyanidins, which might be responsible for their strong antioxidant activities. These results indicate a potential market role for berries （especially blueberries） as a functional food ingredient or nutraceutical.

关键词： Berries Antioxidants Phenolics Flavonoids Anthocyanidins

Recyclable High-performance Carbon Fiber Reinforced Epoxy Composites Based on Dithioacetal Covalent Adaptive Network

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Chinese Journal of Polymer Science 2024年第10期42卷 1514-1524,I0011页

作者： Gui-Lian Shi Ting-cheng Li Dao-hong zhang Jun-Heng zhang Key Laboratory of Catalysis and Energy Materials Chemistry of Ministry of Education&Hubei Key Laboratory of Catalysis and Materials Science Hubei R&D Center of Hyperbranched Polymers Synthesis and ApplicationsSouth-Central Minzu UniversityWuhan430074China State Key Laboratory of New Textile Materials and Advanced Processing Technologies Wuhan Textile UniversityWuhan430200China Ministry-of-Education Key Laboratory for the Green Preparation and Application of Functional Materials Hubei UniversityWuhan430062Chin

Recycling of carbon fiber reinforced composites is important for sustainable development and the circular *** the use of dynamic chemistry,developing high-strength recyclable CFRPs remains a major challenge due to the mutual exclusivity between the dynamic and mechanical properties of ***,we developed a high-strength recyclable epoxy resin(HREP)based on dynamic dithioacetal covalent adaptive network using diglycidyl ether bisphenol A(DGEBA),pentaerythritol tetra(3-mercapto-propionate)(PETMP),and vanillin epoxy resin(VEPR).At high temperatures,the exchange reaction of thermally activated dithioacetals accelerated the rearrangement of the network,giving it significant reprocessing ***,HREP exhibited excellent solvent resistance due to the increased cross-linking *** this high-strength recyclable epoxy resin as the matrix and carbon fiber modified with hyperbranched ionic liquids(HBP-AMIM+PF6-)as the reinforcing agent,high performance CFRPs were successfully *** tensile strength,interfacial shear strength(IFSS)and interlaminar shear strength(ILSS)of the optimized formulation(HREP20/CF-HBPPF6)were 1016.1,70.8 and 76.0 MPa,*** addition,the CFRPs demonstrated excellent solvent and acid/*** CFRPs could completely degrade within 24 h in DMSO at 140℃,and the recycled CF still maintained the same tensile strength and ILSS as the original after multiple degradation cycles.

关键词： Epoxy resin Hyperbranched ionic liquid Recycling Carbon fiber Composites

Comparison of postoperative complications between internal and external pancreatic duct stenting during pancreaticoduodenectomy: a meta-analysis

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Chinese Journal of Cancer Research 2015年第4期27卷 397-407页

作者： Fa-Yong Ke Xiang-Song Wu Yong zhang hong-cheng zhang Ming-Zhe Weng Ying-Bin Liu Christopher Wolfgang Wei Gong Department of General Surgery Xinhua Hospital Shanghai Jiao Tong University School of Medicine Department of Hepatobiliary and Pancreatic Surgery Johns Hopkins School of Medicine

Background：Two types of pancreatic duct stents are used to improve postoperative outcomes of pancreatic *** aim of this meta-analysis was to evaluate and compare the postoperative outcomes of patients with internal or external stenting during pancreaticoduodenectomy（PD）.Methods：We searched Pub Med,EMBASE,the Cochrane Library and Web of Science databases until the end of December,*** comparing outcomes of external *** stent placement in PD were eligible for *** literature was extracted and assessed by two independent ***：Seven articles were identified for inclusion：three randomized controlled trials（RCTs）and four observational clinical studies（OCS）.The meta-analyses revealed that use of external stents had advantage on reducing the incidences of pancreatic fistula（PF）in total[odds ratio（OR）=0.69;95%confidence interval（CI）,0.48-0.99;P=0.04],PF in soft pancreas（OR=0.30;95%CI,0.16-0.56;P=0.0002）and delayed gastric emptying（DGE）（OR=0.58;95%CI,0.38-0.89;P=0.01）compared with internal *** were no significant differences in other postoperative outcomes between two stenting methods,including postoperative morbidity（OR=0.93;95%CI,0.39-2.23;P=0.88）,overall mortality（OR=0.70;95%CI,0.22-2.25;P=0.55）,and intra-abdominal collections（OR=0.67;95%CI,0.26-1.71;P=0.40）.Conclusions：Based upon this meta-analysis,the use of external pancreatic stents might have potential benefit in reducing the incidence of PF and *** to the limited number of original studies,more RCTs are needed to further support our result and clarify the issue.

关键词： Pancreatic duct stent pancreaticoduodenectomy(PD) meta-analysis

Endosulfan residues and farmers’replacement behaviors of endosulfan in the north-west inland cotton region

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Frontiers of Environmental Science & Engineering 2024年第4期18卷 35-47页

作者： Shuyan Zhou Yang zhang Jingjing Wang Shikun cheng Fuyan Zhuo Yun hong School of Energy and Environmental Engineering University of Science and Technology Beijing 100083China Foreign Environmental Cooperation Center Ministry of Ecology and Environment of the People’s Republic of ChinaBeijing 100035China United Nations Development Programme in China Beijing 100600China National Agro-Tech Extension and Service Center Beijing 100125China

We assessed the situation of endosulfan residues in cotton fields after the endosulfan ban came into effect and the current knowledge,attitude,and practice(KAP)of cotton farmers on the phase-out of endosulfan and the application of alternative *** samples(n=91)of cotton fields were collected from the major cotton-producing areas in China,namely the north-west inland cotton region,and the endosulfan residues were analyzed.A KAP survey was carried out for cotton farmers,and 291 questionnaires were *** influences of gender,age,education background,cotton planting years,publicity and training,income sources,and other factors on cotton farmers’KAP were *** results showed that endosulfan sulfate was the main endosulfan residue in the soil,followed byβ-endosulfan andα-endosulfan,the average residual contents were 0.569,0.139,and 0.060μg/kg,*** results of the KAP study showed that cotton farmers scored low on knowledge about the phase-out of endosulfan and the application of alternative technologies but high on attitude and *** number of family members,years of cotton planting,age,and the cottonplanting area had different degrees of influence on KAP *** training could significantly improve the KAP scores of cotton farmers;training should be more targeted and designed reasonably for key groups,such as men and the population under 30,followed by training them to use pesticides *** large-scale cotton growers,training should focus on green prevention and control technologies.

关键词： Cotton fields Endosulfan residues Farmers KAP survey Replacement behaviours

HCSP-Net:A Novel Model of Age-Related Macular Degeneration Classification Based on Color Fundus Photography

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Computers, Materials & Continua 2024年第4期79卷 391-407页

作者： cheng Wan Jiani Zhao Xiangqian hong Weihua Yang Shaochong zhang College of Electronic and Information Engineering/College of Integrated Circuits Nanjing University of Aeronautics and AstronauticsNanjing211106China Shenzhen Eye Institute Shenzhen Eye HospitalJinan UniversityShenzhen518040China

Age-related macular degeneration(AMD)ranks third among the most common causes of *** the most conventional and direct method for identifying AMD,color fundus photography has become prominent owing to its consistency,ease of use,and good quality in extensive clinical *** this study,a convolutional neural network(CSPDarknet53)was combined with a transformer to construct a new hybrid model,*** hybrid model was employed to tri-classify color fundus photography into the normal macula(NM),dry macular degeneration(DMD),and wet macular degeneration(WMD)based on clinical classification manifestations,thus identifying and resolving AMD as early as possible with color fundus *** further enhance the performance of this model,grouped convolution was introduced in this study without significantly increasing the number of ***-Net was validated using an independent test *** average precision of HCSPNet in the diagnosis of AMD was 99.2%,the recall rate was 98.2%,the F1-Score was 98.7%,the PPV(positive predictive value)was 99.2%,and the NPV(negative predictive value)was 99.6%.Moreover,a knowledge distillation approach was also adopted to develop a lightweight student network(SCSP-Net).The experimental results revealed a noteworthy enhancement in the accuracy of SCSP-Net,rising from 94%to 97%,while remarkably reducing the parameter count to a quarter of *** attribute positions SCSP-Net as a highly suitable candidate for the deployment of resource-constrained devices,which may provide ophthalmologists with an efficient tool for diagnosing AMD.

关键词： Computer-aided diagnosis deep learning age-related macular degeneration transformer

Orientational growth behavior and mechanism of delta(δ)phase precipitation in cold-rolled Inconel 718 alloy during heat treatment

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Journal of Iron and Steel Research International 2024年第1期31卷 264-274页

作者： Neng-yong Ye Guang-liang zhang Tian-yue Huang Ming cheng Shi-hong zhang Lei Wang School of Materials Science&Engineering Taizhou UniversityTaizhou318000ZhejiangChina Institute of Metal Research Chinese Academy of SciencesShenyang110016LiaoningChina

Due to the important role ofδphase's quantity and morphology in the mechanical and fatigue properties of Inconel 718 alloy and its components,it is necessary to renew insights into the effect of cold deformation on theδphase precipitation,especially on the morphology ***,the nucleation and growth behavior ofδphase in cold-rolled Inconel 718 alloy during aging were *** results show that the precipitation rate and volume fraction ofδphase increase with increasing the cold rolling reduction from 10%to 50%.The volume fraction ofδphase reaches equilibrium after 5 h,remaining at 5.98%,6.52%,and 6.79%under different rolling reductions(10%,30%,and 50%),*** nucleation ofδphase mainly occurs on different sites(grain boundaries,new twin boundaries and old twin boundaries)under 10%rolling reduction,whileδphase mainly nucleates on the new grain boundaries of static recrystallization due to 50%rolling *** the growth ofδphase undergoes a process of alternate orientation growth from spherical(nucleation)→short rod(longitudinal orientation growth)→short rod(radial orientation growth)→dynamic *** 10%rolling reduction,δphase tends to grow into the matrix,while under 50%rolling reduction,the orientation grows faster and is easily affected by the grain boundary curvature.

关键词： Inconel 718 alloy Cold rolling δphase Orientation growth Morphology evolution

Hydrodynamic Characteristics of Undular Tidal Bores in the Qiantang River Based on Field Observations

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China Ocean Engineering 2024年第3期38卷 505-518页

作者： zhang Shu-yu PAN Cun-hong zhang Shen-yang LI Ruo-hua cheng Wenlong XIE Dong-feng Zhejiang Tongji Vocational College of Science and Technology Hangzhou 311231China Zhejiang Institute of Hydraulics and Estuary Hangzhou 310020China

Understanding the undular tidal bores in the Qiantang River is essential for effective river management and *** breaking tidal bores have been studied extensively, reports on undular tidal bores in the Qiantang Riverremain limited. Furthermore, observed data on undular tidal bores fulfilling the requirements of short measurementtime intervals, and spring, medium, and neap tide coverage, and providing detailed data for the global vertical stratificationof flow velocity are quite limited. Based on field observations at Qige in the Qiantang estuary, we analyzedthe characteristics of undular tidal bores. The results showed that the flooding amplitude (a) of the first wave isalways larger than its ebbing amplitude (b). Moreover, the vertical distribution of the maximum flood velocity exhibitesthree shapes, influenced by the tidal range, while that of the maximum ebb velocity exhibites a single shape. Duringthe initial phase of the flood tide in the spring and medium tides, the upper water body experiences multiple oscillatingchanges along the flow direction, corresponding to the alternating process of the crest and trough of the tide levelupon the arrival of the tidal bore. The tidal range is a crucial parameter in tidal bore hydrodynamics. By establishingthe relationship between hydrodynamic parameters and tidal range, other hydrodynamic parameters, such as the tidalbore height, maximum flood depth–averaged velocity, maximum flood stratified velocity at the measurement points,and duration of the flood tide current, can be effectively predicted, thereby providing an important reference for rivermanagement and maintenance.

关键词： tidal bores Qiantang Estuary tidal bore height tidal bore velocity propagation speed