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Multiple isotopes reveal the driving mechanism of high NO_(3)^(-) level and key processes of nitrogen cycling in the lower reaches of Yellow River

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Journal of Environmental Sciences 2024年第4期138卷 597-606页

作者： Qianqian zhang Huiwei Wang lu Liu Tianlun Zhai Xueqing zhang Hebei and China Geological Survey Key Laboratory of Groundwater Remediation Institute of Hydrogeology and Environmental GeologyChinese Academy of Geological SciencesHebei 050061China Geo-Environmental Monitoring Institute of Hebei Province Hebei 050011China Hebei Provincial Laboratory of Water Environmental Science Hebei 050037China Hebei Provincial Academy of Ecological Environmental Science Hebei 050037China

The continuous increase of nitrate(NO_(3)^(-))level in rivers is a hot issue in the ***,the driving mechanism of high NO_(3)^(-)level in large rivers is still lacking,which has limited the use of river water and increased the cost of water *** this study,multiple isotopes and source resolution models are applied to identify the driving mechanism of high NO_(3)^(-)level and key processes of nitrogen cycling in the lower reaches of the Yellow River(LRYR).The major sources of NO_(3)^(-)were sewage and manure(SAM)in the low-flow season and soil nitrogen(SN)and chemical fertilizer(CF)in the high-flow *** was the most key process of nitrogen cycling in the ***,in the biological removal processes,denitrification may not occur *** temporal variation of contributions of NO_(3)^(-)sources were estimated by a source resolution model in the *** proportional contributions of SAM and CF to NO_(3)^(-)in the low-flow and high-flow season were 32.5%-52.3%,44.2%-46.2%and 36.0%-40.8%,54.9%-56.9%,*** driving mechanisms of high NO_(3)^(-)level were unreasonable sewage discharge,intensity rainfall runoff,nitrification and lack of nitrate removal *** control the NO_(3)^(-)concentration,targeted measures should be implemented to improve the capacity of sewage and wastewater treatment,increase the utilization efficiency of nitrogen fertilizer and construct ecological *** study deepens the understanding of the driving mechanism of high nitrate level and provides a vital reference for nitrogen pollution control in rivers to other area of the world.

关键词： Nitrate Driving mechanism Nitrogen cycle Source apportionment Transformation Yellow River

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Optimal Planning of Hybrid AC/DC Low-voltage Distribution Networks Considering DC Conversion of Three-phase Four-wire Low-voltage AC Systems

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Journal of Modern Power Systems and Clean Energy 2024年第1期12卷 141-153页

作者： Bo zhang lu zhang Wei Tang Gen Li Chen Wang the College of Information and Electrical Engineering China Agricultural UniversityBeijing 100083China the Electric Energy Group Department of Engineering TechnologyTechnical University of Denmark(DTU)2750 BallerupDenmark the Power Distribution Technology Center State Grid Beijing Electric Power Research InstituteBeijing 100075China

The increasing integration of distributed household photovoltaics(PVs)and electric vehicles(EVs)may further ag gravate voltage violations and unbalance of low-voltage distribu tion networks(LVDNs).DC distribution networks can increase the accommodation of PVs and EVs and mitigate mutilple pow er quality problems by the flexible power regulation capability of voltage source *** paper proposes schemes to es tablish hybrid AC/DC LVDNs considering the conversion of the existing three-phase four-wire low-voltage AC systems to DC op *** characteristics and DC conversion constraints of typical LVDNs are *** addition,converter configura tions for typical LVDNs are proposed based on the three-phase four-wire characteristics and quantitative analysis of various DC ***,an optimal planning method of hybrid AC/DC LVDNs is proposed,which is modeled as a bi-level programming model considering the annual investments and three-phase *** are conducted to verify the effectiveness of the proposed optimal planning *** ulation results show that the proposed optimal planning method can increase the integration of PVs while simultaneously reduc ing issues related to voltage violation and unbalance.

关键词： Optimal planning low-voltage distribution net work three-phase unbalance DC conversion

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A Disulfide-Based Poly(ether-b-amide)Copolymer with Rapid Self-healing Ability under Moderate Conditions

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Chinese Journal of Chemistry 2024年第9期42卷 943-950页

作者： Weijan lu ping Zhu Ying Zhao Dujin Wang xia Dong Institute of Chemistry Chinese Academy of SciencesBeijing 100190China Schoolof Chemical Sciences University of Chinese Academy of SciencesBeijing 100049China

Comprehensive Summary A disulfide-based poly(ether-b-amide)copolymer with rapid self-healing capability under moderate conditions was synthesized from 4,4’-dithiodibutyric acid(DTDBA),isophorondiamine(IPDA)and poly(tetramethylene oxide)(PTMO)based on a two-step *** incorporation of IPDA with asymmetric structure and substantial steric hindrance not only effectively decreased the number of regular H-bonds,but also inhibited the crystallization of polyamide segments,imparting the synthesized poly(ether-b-amide)copolymer with an amorphous structural *** on the coordination of segmental diffusion and recombination of disulfide bonds and hydrogen bonds,the scratches and damaged mechanical properties of PEBADS-I611 could be completely self-healed after healing at 40°C for only 11 min and 3 h,respectively.

关键词： Poly(ether-b-amide)copolymer Disulfide bonds Hydrogen bonds Polycondensation Smart polymers Self-healing

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A Beautiful China Initiative Towards the Harmony between Humanity and the Nature

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Frontiers of Environmental Science & Engineering 2024年第6期18卷 33-41页

作者： Changbo Qin Qiang Xue Jiawei zhang lu lu Shangao Xiong Yang xiao xiaojing zhang Jinnan Wang Institute of Strategic Planning Chinese Academy of Environmental PlanningBeijing 100041China The Center for Beautiful China Chinese Academy of Environmental PlanningBeijing 100041China Chinese Academy of Environmental Planning Beijing 100041China

The Beautiful China Initiative(BCI)is a vivid embodiment of the harmonious coexistence between humans and nature during *** the BCI is an effective method for achieving the goals of building a beautiful China,while offering a“Chinese solution”to global sustainable *** article summarizes the progress and main experiences of the BCI,as well as analyzing the primary challenges facing its future ***,five policy recommendations are proposed,which emphasize the importance of top-level design,coordinated planning,and a robust support system in the implementation of the BCI.

关键词： Beautiful China Initiative Ecological civilization Practice Policy suggestion

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Synthesis of a High-Efficiency Demulsifier and Study on Optimal Demulsification Conditions

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China Petroleum Processing & Petrochemical Technology 2024年第1期26卷 107-115页

作者： Zhu Shuai zhang YingYu Gui xia College of Chemical Engineering Nanjing Tech University30 Puzhunan RoadNanjing 211816China

Oil and water separation has always been a top priority in the oil *** this study,a series of hyperbranched fluorinated polyamine-amine polymers(HFPA1-5)were synthesized directly using an improved“one-pot method.”The highly active fluorinated p-trifluoromethylaniline was used as the core raw material,while diethylenetriamine and methyl acrylate were used as the chain segment.A hyperbranched fluorine-containing polyamine-amine demulsifier(NHFPA6)was obtained through nano-grafting copolymerization of *** enhance the demulsification and dehydration performance,the copolymerized HFPA6 was modified and ***,the effects of the combination ratio,demulsifier concentration,demulsification time,and demulsification temperature on the demulsification effect were *** results revealed that a combination ratio of DE-401:NHFPA6=1:1,a demulsification temperature of 50℃,a demulsification time of 60 min,and a demulsifier concentration of 150 mg/L yielded a dehydration rate as high as 99.80%.A response surface optimization design of demulsification conditions was *** model verified that the optimal demulsification conditions were 50℃,300 mg/L,and 90 ***,considering the economic benefits of factories,it is more favorable to select demulsification conditions with a shorter time and lower concentration when the dehydration standard is ***,the demulsification conditions were selected as 50℃,150 mg/L,and 60 *** to existing demulsifiers,the demulsifier developed in this study exhibits a lower demulsification temperature and higher demulsification efficiency.

关键词： hyperbranched fluorinated polyamine-amine nano-SiO_(2)

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Impairment of Autophagic Flux After Hypobaric Hypoxia Potentiates Oxidative Stress and Cognitive Function Disturbances in Mice

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Neuroscience Bulletin 2024年第1期40卷 35-49页

作者： Shuhui Dai Yuan Feng Chuanhao lu Hongchen zhang Wenke Ma Wenyu Xie Xiuquan Wu Peng luo Lei zhang Fei Fei Zhou Fei xia Li Department of Neurosurgery Xijing HospitalFourth Military Medical UniversityXi'an 710000China National Translational Science Center for Molecular Medicine and Department of Cell Biology Fourth Military Medical UniversityXi'an 710000China Department of Neurosurgery The Central Hospital of BaojiBaoji 721000China Department of Ophthalmology Xijing HospitalFourth Military Medical UniversityXi'an 710000China

Acute hypobaric hypoxic brain damage is a potentially fatal high-altitude *** plays a critical role in ischemic brain injury,but its role in hypo-baric hypoxia(HH)remains *** we used an HH chamber to demonstrate that acute HH exposure impairs autophagic activity in both the early and late stages of the mouse brain,and is partially responsible for HH-induced oxidative stress,neuronal loss,and brain *** autophagic agonist rapamycin only promotes the initiation of *** proteome analysis,a screen showed that protein dynamin2(DNM2)potentially regulates autophagic *** of DNM2 significantly increased the formation of autolysosomes,thus maintaining autophagic flux in combination with ***,the enhancement of autophagic activity attenuated oxidative stress and neurological deficits after HH *** results contribute to evidence supporting the conclusion that DNM2-mediated autophagic flux represents a new therapeutic target in HH-induced brain damage.

关键词： Autophagy-Proteomics Oxidative stress Hypobaric hypoxia-Brain injury

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Reliability analysis of carbon fiber rod-reinforced umbilical cable under tension using an improved sampling method

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Petroleum Science 2024年第4期21卷 2769-2778页

作者： Yu zhang Hong-Yu zhang Ran xia Si-Ao Jiang Fang Wang College of Safety and Ocean Engineering China University of Petroleum China Academy of Aerospace Aerodynamics China Aerospace Science and Technology Group College of Engineering Science and Technology Shanghai Ocean University

The umbilical cable is a vital component of subsea production systems that provide power, chemical agents, control signals et al., and its requirement for reliability is exceedingly high. However, as the umbilical cable is a composite structure comprising multiple functional units, the reliability analysis of such cables involves numerous parameters that can impact calculation efficiency. In this paper, the reliability analysis of a new kind of umbilical cable with carbon fiber rod under tension is analyzed. The global dynamic analytical model is first established to determine the maximum tension load, then the local analytical model of umbilical cable including each unit are constructed by finite element method(FEM). Based on the mechanical analytical model, the reliability of umbilical cable under tension load is studied using response surface method(RSM) and Monte Carlo method. During the calculation process, a new tangent plane sampling method to calculate the response surface function(RSF) is proposed in this paper, which could make sampling points faster come close to the RSF curve, and it is proved that the calculation efficiency increases about 33% comparing with traditional method.

关键词： Umbilical cable Carbon fiber rod Failure analysis Response surface method Reliability

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Inflammatory Factor IL1αInduces Aberrant Astrocyte Proliferation in Spinal Cord Injury Through the Grin2c/Ca^(2+)/CaMK2b Pathway

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Neuroscience Bulletin 2024年第4期40卷 421-438页

作者： Yu xia lu Ding Changlin zhang Qi Xu Ming Shi Tianshun Gao Feng-Quan Zhou David Y.B.Deng Scientific Research Center The Seventh Affiliated Hospital of Sun Yat-sen UniversityShenzhen518107China Department of Gynecology The Seventh Affiliated Hospital of Sun Yat-sen UniversityShenzhen518107China Pelvic Floor Disorders Center The Seventh Affiliated Hospital of Sun Yat-sen UniversityShenzhen518107China Big Data Center The Seventh Affiliated Hospital of Sun Yat-sen UniversityShenzhen518107China Sir Run Run Shaw Hospital Zhejiang University School of MedicineHangzhou310016China Orthopaedic and Neurological Repair Center The Seventh Affiliated Hospital of Sun Yat-sen UniversityShenzhen518107China

Spinal cord injury(SCI)is one of the most devastating traumas,and the aberrant proliferation of astrocytes usually causes neurological ***,the mechanism underlying astrocyte over-proliferation after SCI is ***2c(glutamate ionotropic receptor type 2c)plays an essential role in cell *** bioinformatic analysis indicated that Grin2c and Ca^(2+)transport functions were inhibited in astrocytes after *** of Grin2c stimulated astrocyte proliferation by inhibiting the Ca^(2+)/calmodulin-dependent protein kinase 2b(CaMK2b)pathway in *** screening different inflammatory factors,interleukin 1α(IL1α)was further found to inhibit Grin2c/Ca^(2+)/CaMK2b and enhance astrocyte proliferation in an oxidative damage *** of IL1αusing neutralizing antibody resulted in increased Grin2c expression and the inhibition of astrocyte proliferation ***,this study suggests that IL1αpromotes astrocyte proliferation by suppressing the Grin2c/Ca^(2+)/CaMK2b pathway after SCI,revealing a novel pathological mechanism of astrocyte proliferation,and may provide potential targets for SCI repair.

关键词： IL1α Grin2c Astrocyte Spinal cord injury

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Wetting-drying effect on the strength and microstructure of cementphosphogypsum stabilized soils

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Journal of Rock Mechanics and Geotechnical Engineering 2024年第3期16卷 1049-1058页

作者： Lingling Zeng xia Bian Jiaxing Weng Tao zhang College of Civil Engineering Zhejiang University of TechnologyHanzhou310014China Key Laboratory of Ministry of Education for Geomechanics and Embankment Engineering Hohai UniversityNanjing210098China State Key Laboratory for Geomechanics and Deep Underground Engineering China University of Mining and TechnologyXuzhou221116China Jiangsu Water Source Company Ltd.of the Eastern Route of the South-to-North Water Diversion Project Nanjing210000China Power China Zhongnan Engineering Corporation Limited Changsha410027China

Phosphogypsum has often been used as an effective and environmentally friendly binder for partial replacement of cement,improving the engineering properties of slurries with high water ***,the influence of phosphogypsum on the physicomechnical properties of stabilized soil subjected to wettingedrying cycles is not well understood to *** this study,the effect of phosphogypsum on the durability of stabilized soil was studied by conducting a series of laboratory experiments,illustrating the changes in mass loss,pH value and unconfined compressive strength(qu)with wettingdrying *** test results showed that the presence of phosphogypsum significantly restrained the mass loss in the early stage(lower than the 4th cycle),which in turn led to a higher qu of stabilized soil than that without *** the 4th cycle,a sudden increase in mass loss was observed for stabilized soil with phosphogypsum,resulting in a significant drop in qu to a value lower than those without phosphogypsum at the 6th *** addition,the qu of stabilized soils correlated well with the measured soil pH irrespective of phosphogypsum content for all wettingedrying *** to the microstructure observation via scanning electron microscope(SEM)and X-ray diffraction(XRD)tests,the mechanisms relating the sudden loss of qu for the stabilized soils with phosphogypsum after the 4th wetting-drying cycle are summarized as follows:(i)the disappearance of ettringite weakening the cementation bonding effect,(ii)the generation of a larger extent of microcrack,and(iii)a lower pH value,in comparison with the stabilized soil without phosphogypsum.

关键词： Wetting-drying Phosphogypsum Microstructure Durability

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Resveratrol combats chronic diseases through enhancing mitochondrial quality

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Food Science and Human Wellness 2024年第2期13卷 597-610页

作者： Weichu Tao Hu zhang xia Jiang Ning Chen Tianjiu Research and Development Center for Exercise Nutrition and Foods Hubei Key Laboratory of Exercise Training and MonitoringCollege of Sports MedicineWuhan Sports UniversityWuhan 430079China The University Hospital of Wuhan Sports University Wuhan 430079China

Resveratrol(RSV),as a functional food component extracted from natural plants,has been widely studied and recognized in preventing and treating various diseases,with major mechanisms including executing anti-inflammation and anti-oxidation functions,and improving mitochondrial *** diseases as non-communicable diseases are mainly caused by multiple factors,such as physiological decline and dysfunction in the body,and have become a significant challenge on public health *** is worth noting that chronic diseases such as Alzheimer's disease(AD),Parkinson's disease(PD),muscle atrophy,cardiovascular disease,obesity,and cancer are accompanied by abnormal mitochondrial ***,targeted regulation of mitochondria may be a meaningful way to prevent and treat chronic *** evidence has confirmed that RSV is actively involved in regulating mitochondria,and it has become an essential consideration to prevent and treat chronic diseases through targeting mitochondria and improving corresponding *** this article,current studies on RSV to optimize mitochondrial quality for preventing and alleviating chronic disease are systematically summarized,which can provide a theoretical reference for the development of functional foods or drugs to combat chronic diseases.

关键词： Resveratrol Functional food Mitochondrial quality Chronic disease Anti-inflammation Anti-oxidation

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