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

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Journal of Environm.ntal Sciences 2024年第1期135卷 703-714页

作者： Yuanhui Cheng hong zhang Wei Yin State Key Laboratory of Environm.ntal 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 am.ng 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 environm.nt,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

Preparation,characterization and antioxidant activity analysis of three maillard glycosylated bone collagen hydrolysates from chicken,porcine and bovine

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Food Science and Hum.n Wellness 2024年第4期13卷 2002-2013页

作者： Liwei Qi hongru zhang Yujie Guo hong Liu Chunhui zhang Key Laboratory of Agro-Products Processing Ministry of Agriculture and Rural AffairsInstitute of Food Science and TechnologyChinese Academy of Agricultural SciencesBeijing 100193China Laboratory of Biomass and Green Technologies University of Liege-Gembloux Agro-Bio TechPassage des déportés 2Gembloux B-5030Belgium

Bone collagen hydrolysates(peptides)derived from byproduct of animal product processing have been used to produce commercially valuable products due to their potential antioxidant *** glycosylated reaction is considered as a promising method to enhance the antioxidant activity of ***,this research aims at investigating the maillard glycosylation activity and antioxidant activity of bone collagen hydrolysates from different *** this study,3 glycosylated bone collagen hydrolysates were prepared and characterized,and cytotoxicity and antioxidant activity were analyzed and *** free am.no groups loss,browning intensity,and fluorescence intensity of G-Cbcp(glycosylated chicken bone collagen hydrolysates(peptides))were the heaviest,followed by G-Pbcp(glycosylated porcine bone collagen hydrolysates(peptides))and G-Bbcp(glycosylated bovine bone collagen hydrolysates(peptides)).The results of am.no acid analysis showed that am.no acid composition of different bone collagen hydrolysates was significantly different and the am.no acid decreased to different degrees after maillard glycosylated reaction,which may lead to differences in maillard glycosylated reaction ***,the 3 glycosylated hydrolysates showed no significant *** results showed that glycosylation process significantly increased the antioxidant activity of bone collagen hydrolysates,and G-Cbcp showed the strongest antioxidant activity,followed by G-Pbcp and ***,compared with the bone collagen hydrolysates,3 glycosylated hydrolysates showed significant characteristic and structural changes,and higher antioxidant activity.

关键词： Bone collagen hydrolysates Glycosylation reaction Antioxidant activity

Experim.ntal study and numerical simulation of the impact of under-sleeper pads on the dynamic and static mechanical behavior of heavy-haul railway ballast track

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Railway Engineering Science 2024年第3期32卷 384-400页

作者： Yihao Chi hong Xiao Yang Wang Zhihai zhang mahantesh m.nadakatti School of Civil Engineering Beijing Jiaotong UniversityBeijing 100044China Beijing Key Laboratory of Track Engineering Beijing Jiaotong UniversityBeijing 100044China Departm.nt of mechanical Engg KLSGITBelgaumKarnataka 590008India

Laying the under-sleeper pad(USP)is one of the effective measures comm.nly used to delay ballast degradation and reduce maintenance *** explore the impact of application of the USP on the dynamic and static mechanical behavior of the ballast track in the heavy-haul railway system.numerical simulation models of the ballast bed with USP and without USP are presented in this paper by using the discrete elem.nt method(DEm)-multi-flexible body dynamic(mFBD)coupling analysis *** ballast bed support stiffness test and dynamic displacem.nt tests were carried out on the actual operation of a heavy-haul railway line to verify the validity of the *** results show that using the USP results in a 43.01%reduction in the ballast bed support stiffness and achieves a more uniform distribution of track loads on the *** effectively reduces the load borne by the sleeper directly under the wheel load,with a 7.89%reduction in the pressure on the ***,the laying of the USP changes the lateral resistance sharing ratio of the ballast bed,significantly reducing the stress level of the ballast bed under train loads,with an average stress reduction of 42.19 *** also reduces the plastic displacem.nt of ballast particles and lowers the peak value of rotational angular velocity by about 50%to 70%,which is conducive to slowing down ballast bed settlem.nt deformation and reducing maintenance *** summary,laying the USP has a potential value in enhancing the stability and extending the lifespan of the ballast bed in heavy-haul railway systems.

关键词： Heavy-haul railway Under-sleeper pad Discrete elem.nt method multi-flexible body dynamic coupling analysis mechanical behavior Quality state

Research on casing deformation prevention technology based on cem.nting slurry system optimization

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Petroleum Science 2024年第2期21卷 1231-1240页

作者： Yan Yan m.ng Cai Wen-Hai ma Xiao-Chuan zhang Li-hong Han Yong-hong Liu State Key Laboratory for Perform.nce and Structure Safety of Petroleum Tubular Goods and Equipm.nt materials CNPC Tubular Goods Research InstituteXi©an710077ShaanxiChina College of mechanical and Electrical Engineering China University of Petroleum(East China)Qingdao266580ShandongChina Shale Gas Evaluation and Exploitation Key Laboratory of Sichuan Province Chengdu610095SichuanChina CnPC Daqing Oilfield Company Daqing163453HeilongjiangChina

The casing deformation prevention technology based on the optimization of cem.nt slurry is proposed to reduce the casing deformation of shale oil and gas wells during hydraulic fracturing. In this paper, the fracture mechanism of hollow particles in cem.nt sheath was firstly analyzed by discrete elem.nt method, and the effect of hollow particles in cem.nt on casing deformation was investigated by laboratory experim.nt method. Finally, field test was carried out to verify the improvem.nt effect of the casing deformation based on cem.nt slurry modification. The results show that the formation displacem.nt can be absorbed effectively by hollow particles inside the cem.nt transferring the excessive deformation away from casing. The particles in the uncem.nted state provide deformation space during formation slipping. The casing with diameter of 139.7 mm could be passed through by bridge plug with the diameter of 99 mm when the mass ratio of particle/cem.nt reaches 1:4. According to the field test feedback, the method based on optimization of cem.nt slurry can effectively reduce the risk of casing deformation, and the recomm.nded range of hollow microbeads content in the cem.nt slurry is between 15% and 25%.

关键词： Cem.nt slurry Hollow ceramsite Casing deformation Formation slip Field test

Chiral transmission by an open evolution trajectory in a non-Hermitian system

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Light(Science & Applications) 2024年第4期13卷 628-636页

作者： Xiaoqian Shu Qi Zhong Kai hong Oubo You Jian Wang Guangwei Hu Andrea Alù Shuang zhang Demetrios n.Christodoulides Lin Chen Wuhan national Laboratory for Optoelectronics and School of Optical and Electronic Information Huazhong University of Science and TechnologyWuhan 430074China. Zhejiang Lab Hangzhou 311121China. CREOL College of Optics and PhotonicsUniversity of Central FloridaOrlandoFlorida 32816USA. Departm.nt of Physics The University of Hong KongHong KongChina. School of Electrical and Electronic Engineering Nanyang Technological University50 Nanyang AvenueSingapore 639798Singapore. Photonics Initiative Advanced Science Research CenterCity University of New YorkNew YorkNY 10031USA. Shenzhen Huazhong University of Science and Technology Research Institute Shenzhen 518063China

Exceptional points(EPs),at which two or more eigenvalues and eigenstates of a resonant system coalesce,are associated with non-Hermitian Hamiltonians with gain and/or loss *** encircling of EPs has received significant interest in recent years,as it has been shown to lead to highly nontrivial phenom.na,such as chiral transmission in which the final state of the system depends on the encircling ***,chiral transmission for a pair of eigenmodes has been realized by establishing a closed dynamical trajectory in parity-time-(PT-)or anti-PT-symmetric *** chiral transmission of symmetry-broken modes,more accessible in practical photonic integrated circuits,has been realized by establishing a closed trajectory encircling EPs in anti-PTsymmetric systems,the dem.nstrated transmission efficiency is very low due to path-dependent ***,we dem.nstrate chiral dynamics in a coupled waveguide system that does not require a closed ***,we explore an open trajectory linking two infinite points having the same asymptotic eigenmodes(not modes in PT-and anti-PT-symmetric systems),dem.nstrating that this platform enables high-efficiency chiral transmission,with each eigenmode localized in a single *** concept is experim.ntally implem.nted in a coupled silicon waveguide system at telecomm.nication *** work provides a new evolution strategy for chiral dynamics with superior perform.nce,laying the foundation for the developm.nt of practical chiral-transmission devices.

关键词： chiral system symmetric

Interfacial reaction between AZ91D magnesium alloy melt and mild steel under high temperature

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China Foundry 2024年第2期21卷 159-167页

作者： Jia-hong Dai Jian-yue zhang Bin Jiang Xiang-jun Xu Zhong-tao Jiang hong-mei Xie Qing-shan Yang Guo-qing zhang College of materials Science and Engineering Yangtze Normal UniversityChongqing 408100China national Engineering Research Center for magnesium Alloys College of Materials Science and EngineeringChongqing UniversityChongqing 400044China Chongqing Jiulongyuan High-tech Industry Group Co. Ltd.Chongqing 400080China Loncin Industry Co. Ltd.Chongqing 400080China Departm.nt of materials Science and Engineering The Ohio State UniversityColumbusOH 43210USA Chongqing Key Laboratory of materials Surface&Interface Science Chongqing University of Arts and SciencesChongqing 402160China School of metallurgy and material Engineering Chongqing University of Science and TechnologyChongqing 401331China

The metallurgical quality control of magnesium(mg)and mg alloys in melting process is required to ensure a satisfied mechanical and corrosion perform.nce,while the typical used steel crucible introduces impurities and interfacial interaction during melting ***,a systematic study about impurities diffusion and interfacial interaction between molten mg and steel is *** the present study,the interfacial reaction between molten AZ91D mg alloy and mild steel during melting process was investigated with the melting temperatures of 700℃,750℃ and 800℃.The results show that Al(Fe,mn)intermetallic layer is the intermetallic primarily formed at the interfaces of AZ91D melt and mild ***,Al_(8)(mn,Fe)5is indexed between Al(Fe,mn)and ***_(3)C appears between the mild steel and Al(Fe,mn)at 700℃ and 750℃,but absent at 800℃ due to the increased solubility of carbon in mg *** is found that the growth of the intermetallic layer is controlled by diffusion mechanism,and Al and mn are the dom.nant diffusing species in the whole interfacial reaction *** measuring the thickness of different layers,the growth constant was *** increases from 1.89(±0.03)×10^(-12)m^(2)·s^(-1)at 700℃ to 3.05(±0.05)×10^(-12)m^(2)·s^(-1)at 750℃,and 5.18(±0.05)×10^(-12)m^(2)·s^(-1)at 800℃.meanwhile,the content of Fe is linearly increased in AZ91D with the increase of holding time at 700℃ and 750℃,while it shows a significantly increm.nt after holding for 8 h at 800℃,indicating holding temperature is more crucial to determ.ne the Fe content of AZ91D than holding time.

关键词： AZ91D mild steel interface reaction intermetallic growth kinetics

Concerted Steric and Electronic Strategy in Thermostable Salicylaldim.nato nickel Catalysts for Ethylene(Co)polymerization

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Chinese Journal of Polymer Science 2024年第8期42卷 1085-1092页

作者： hong-Yu Ji hong-Liang mu Chun-Feng Tang Yu-Xing zhang Yue Chi Zhong-Bao Jian Key Laboratory of Advanced Structural materials Ministry of EducationSchool of Materials Science and EngineeringChangchun University of TechnologyChangchun 130012China State Key Laboratory of Polymer Physics and Chemistry Changchun Institute of Applied ChemistryChinese Academy of SciencesChangchun 130022China

Olefin polymerization is one of the most im portant chemical reactions in *** work presents a strategy that emphasizes the synergistic meta/poro-steric hindrance of n-aryl groups and electronic effects in newly synthesized neutral salicylaldim.nato nickel *** nickel(Ⅱ)catalysts exhibit exceptional thermostability,ranging from 30℃to 130℃,dem.nstrating enhanced catalytic activities and broadly regulated polyethylene molecular weights(3-341 kg·mol^(-1))and controlled polymer branch density(2-102 brs/1000C).The preferred catalyst ni3 with concerted steric and electronic effects enables the production of solid-state semi-crystalline polyethylene materials at temperatures below 90℃.notably,ni3 exhibits an impressive tolerance of 110℃and can withstand even the challenging polymerization temperature of 130℃,leading to the production of polyethylene wax and ***,functionalized polyethylene is produced.

关键词： Polyolefin Salicylaldim.nato ligand nickel catalyst Oil Wax

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

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Frontiers of Environm.ntal 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 Environm.ntal Engineering University of Science and Technology Beijing 100083China Foreign Environm.ntal Cooperation Center Ministry of Ecology and Environment of the People’s Republic of ChinaBeijing 100035China United nations Developm.nt 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 m.n 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 Replacem.nt behaviours

Efficient Pt/KFI zeolite catalysts for the selective catalytic reduction of nOxby hydrogen

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Journal of Environm.ntal Sciences 2024年第4期138卷 102-111页

作者： Ligang zhang Yulong Shan Zidi Yan Zhongqi Liu Yunbo Yu hong He School of Rare Earths University of Science and Technology of ChinaHefei 230026China Ganjiang Innovation Academy Chinese Academy of SciencesGanzhou 341119China State Key Joint Laboratory of Environm.nt Simulation and Pollution Control Research Center for Eco-Environmental SciencesChinese Academy of SciencesBeijing 100085China

Aim.ng at purification of nO_(x)from hydrogen internal combustion engines(HICEs),the hydrogen selective catalytic reduction(H_(2)-SCR)reaction was investigated over a series of Pt/KFI zeolite catalysts.H_(2)can readily reduce nO_(x)to n_(2)and n_(2)O while O_(2)inhibited the denO_(x)efficiency by consum.ng the reductant H_(2).The Pt/KFI zeolite catalysts with Pt loading below 0.1wt.% are optimized H_(2)-SCR catalysts due to its suitable operation temperature window since high Pt loading favors the H_(2)-O_(2)reaction which lead to the insufficient of *** to metal Pt^(0)species,Pt^(δ+)species showed lower activation energy of H_(2)-SCR reaction and thought to be as reasonable active ***,Eley-Rideal(E-R)reaction mechanism was proposed as evidenced by the reaction orders in kinetic ***,the optimized reactor was designed with hybrid Pt/KFI catalysts with various Pt loading which achieve a high nO_(x)conversion in a wide temperature range.

关键词： Pt/KFI zeolite Pt loading H_(2)-SCR Reaction conditions Kinetics studies