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Riverine sulfate sources and behaviors in arid environment,Northwest China:Constraints from sulfur and oxygen isotopes

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Journal of Environmental Sciences 2024年第3期137卷 716-731页

作者： Yifu xu Wenjing Liu Bing xu zhifang xu Key Laboratory of Cenozoic Geology and Environment Institute of Geology and GeophysicsChinese Academy of SciencesBeijing 100029China Innovation Academy for Earth Science Chinese Academy of SciencesBeijing 100029China University of Chinese Academy of Sciences Beijing 100049China

The fate of riverine sulfate ion (SO_(4)^(2-)) and its environmental effects in arid environment are difficult to evaluate due to its complicated sources and strongly coupled behaviors with water cycle which is significantly modified by humans.To understand the sulfur cycle in aquatic systems in arid environment,the chemical and sulfur and oxygen isotopic compositions (δ^(34)S_(SO4)and δ^(18)O_(SO4)) of major rivers around the Badain Jaran Desert,northwestern China,were investigated.These rivers had averaged SO_(4)^(2-)content at 1336μmol/L,over 10times higher than the global average.The δ^(34)S_(SO4)and δ^(18)O_(SO4)values ranged from-5.3‰to+11.8‰and+1.6‰to+12.8‰,respectively.The end-member analysis and the inverse model showed that riverine sulfate was mainly derived from evaporites dissolution (0-87%),sulfide oxidation (13%-100%) and precipitation (0-33%),indicating heterogeneity in sulfur sources and behaviors along the river drainage with the lithology variations and climate gradients.Multiple isotopic tools combining with hydro-chemistry compositions could be applied to reveal sulfur cycle in arid environment.Based on the calculation,sulfide oxidation plays the primary role in the headwater and upstream in the Qilian-Mountains area,where sulfide is widely exposed.While the proportion of evaporites dissolution contributing to riverine sulfate is much higher in downstream in a drier environment.Besides,less precipitation and higher temperature can lead to more intensive evaporation,affecting the process of sulfide oxidation and enhancing the rates of evaporites dissolution and sulfate precipitation in the basin.

关键词： Sulfur and oxygen isotopes Source apportionment Inverse model Arid environment Inland rivers Northwestern China

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Scientific Advances and Weather Services of the China Meteorological Administration’s National Forecasting Systems during the Beijing 2022 Winter Olympics

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Advances in Atmospheric Sciences 2024年第5期41卷 767-776页

作者： Guo DENG xueshun SHEN Jun DU Jiandong GONG Hua TONG Liantang DENG zhifang xu Jing CHEN Jian SUN Yong WANG Jiangkai HU Jianjie WANG Mingxuan CHEN Huiling YUAN Yutao ZHANG Hongqi LI Yuanzhe WANG Li GAO Li SHENG Da LI Li LI Hao WANG Ying ZHAO Yinglin LI Zhili LIU Wenhua GUO China Meteorological Administration Earth System Modeling and Prediction Centre Beijing 100081China State Key Laboratory of Severe Weather China Meteorological AdministrationBeijing 100081China Key Laboratory of Earth System Modeling and Prediction China Meteorological AdministrationBeijing 100081China National Meteorological Center China Meteorological AdministrationBeijing 100081China Environmental Modeling Center/NCEP/NWS/NOAA College ParkMD 20740USA Nanjing University of Information Science and Technology Nanjing 210044China Institute of Urban Meteorology China Meteorological AdministrationBeijing 100089China School of Atmospheric Sciences and Key Laboratory of Mesoscale Severe Weather/Ministry of Education Nanjing UniversityNanjing 210023China Tsinghua University Beijing 100084China

Since the Beijing 2022 Winter Olympics was the first Winter Olympics in history held in continental winter monsoon climate conditions across complex terrain areas,there is a deficiency of relevant research,operational techniques,and experience.This made providing meteorological services for this event particularly challenging.The China Meteorological Administration(CMA)Earth System Modeling and Prediction Centre,achieved breakthroughs in research on short-and medium-term deterministic and ensemble numerical predictions.Several key technologies crucial for precise winter weather services during the Winter Olympics were developed.A comprehensive framework,known as the Operational System for High-Precision Weather Forecasting for the Winter Olympics,was established.Some of these advancements represent the highest level of capabilities currently available in China.The meteorological service provided to the Beijing 2022 Games also exceeded previous Winter Olympic Games in both variety and quality.This included achievements such as the“100-meter level,minute level”downscaled spatiotemporal resolution and forecasts spanning 1 to 15 days.Around 30 new technologies and over 60 kinds of products that align with the requirements of the Winter Olympics Organizing Committee were developed,and many of these techniques have since been integrated into the CMA’s operational national forecasting systems.These accomplishments were facilitated by a dedicated weather forecasting and research initiative,in conjunction with the preexisting real-time operational forecasting systems of the CMA.This program represents one of the five subprograms of the WMO’s high-impact weather forecasting demonstration project(SMART2022),and continues to play an important role in their Regional Association(RA)II Research Development Project(Hangzhou RDP).Therefore,the research accomplishments and meteorological service experiences from this program will be carried forward into forthcoming highimpact weather forecasting activities.This article provides an

关键词： Beijing Winter Olympic Games CMA national forecasting system data assimilation ensemble forecast bias correction and downscaling machine learning-based fusion methods

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Hydrochemistry and carbon isotope characteristics of Nujiang River water:Implications for CO_(2) budgets of rock weathering in the Tibetan Plateau

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Science China Earth Sciences 2023年第12期66卷 2953-2970页

作者： Wenjing LIU Huiguo SUN Yuanchuan LI zhifang xu Key Laboratory of Cenozoic Geology and Environment Institute of Geology and GeophysicsChinese Academy of SciencesBeijing 100029China College of Earth and Planetary Sciences University of Chinese Academy of SciencesBeijing 100049China

The Tibetan Plateau is one of the most complicated geographical units worldwide in terms of its tectonic and environmental background.Although a hotspot for continental weathering and carbon cycling studies,accurate determination of the weathering carbon budget is challenging in this area,especially sink and source flux quantification and the controlling mechanisms.Compared with other major rivers on the plateau,the Nujiang River is characterized by less human disturbance and maintains a relatively pristine state.This study investigates the high spatiotemporal resolution hydrochemistry and dual-carbon isotope composition(δ~(13)C_(DIC)andΔ~(14)C_(DIC))of river water in the Nujiang River Basin.The results revealed that the solutes and dissolved inorganic carbon in the river water are predominantly derived from rock weathering by carbonic and sulfuric acids,mainly due to the carbonate weathering process,and significantly enhanced by deep carbon sourcing from hot springs in the fault zone.The average contributions of geological and modern carbon in the main stream of the Nujiang River are 35.2%and 64.8%,respectively,and sulfide oxidation contributes>90%of sulfate ions in the river water.After considering the involvement of sulfuric acid generated by sulfide oxidation during rock weathering,the calculated consumption fluxes of atmospheric CO_(2) by silicate and carbonate weathering in the watershed were decreased by approximately 52.0%and 37.4%,respectively,compared with those calculated ignoring this process.Rock weathering of the Nujiang River Basin is a“CO_(2) sink”on a short time scale,while the participation of sulfuric acid makes it a“CO_(2) source”on a geological time scale.The high-frequency observations of ion concentrations,elemental ratios,and calculated contributions of different rock weathering materials indicate that carbonate rock weathering is more sensitive to temperature and runoff variations than silicate rock weathering,with the solute contribution from carbonate weathering increasing significantly

关键词： Tibetan Plateau Nujiang River Basin CO_(2)budgets of rock weathering Hydrochemistry and carbon isotope composition High spatiotemporal resolution

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Effect of 2-m Temperature Data Assimilation in the CMA-MESO 3DVAR System

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Journal of Meteorological Research 2023年第2期37卷 218-233页

作者： zhifang xu Lin ZHANG Ruichun WANG Jiandong GONG CMA Earth System Modeling and Prediction Centre China Meteorological Administration(CMA)Beijing100081 State Key Laboratory of Severe Weather Chinese Academy of Meteorological SciencesChina Meteorological AdministrationBeijing100081 National Meteorological Centre China Meteorological AdministrationBeijing100081

Assimilation of surface observations including 2-m temperature(T_(2m))in numerical weather prediction(NWP)models remains a challenging problem owing to differences between the elevation of model terrain and that of actual observation stations.NWP results can be improved only if surface observations are assimilated appropriately.In this study,a T_(2m)data assimilation scheme that carefully considers misrepresentation of model and station terrain was established by using the three-dimensional variational data assimilation(3DVAR)system of the China Meteorological Administration mesoscale model(CMA-MESO).The corresponding forward observation operator,tangent linear operator,and adjoint operator for the T_(2m)observations under three terrain mismatch treatments were developed.The T_(2m)data were assimilated in the same method as that adopted for temperature sounding data with additional representative errors,when station terrain was 100 m higher than model terrain;otherwise,the T_(2m)data were assimilated by using the surface similarity theory assimilation operator.Furthermore,if station terrain was lower than model terrain,additional representative errors were stipulated and corrected.Test of a rainfall case showed that the observation innovation and analysis residuals both exhibited Gaussian distribution and that the analysis increment was reasonable.Moreover,it was found that on completion of the data assimilation cycle,T_(2m)data assimilation obviously influenced the temperature,wind,and relative humidity fields throughout the troposphere,with the greatest impact evident in the lower layers,and that both the area and the intensity of rainfall were better forecasted,especially for the first 12hours.Long-term continuous experiments for 2–28 February and 5–20 July 2020,further verified that T_(2m)data assimilation reduced deviations not only in T_(2m)but also in 10-m wind forecasts.More importantly,the precipitation equitable threat scores were improved over the two experimental periods.In summary,this study confirme

关键词： 2-m temperature China Meteorological Administration mesoscale model(CMA-MESO) assimilation three-dimensional variational(3DVAR)data assimilation kilometer-scale

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An inspiration to the studies on mechanisms of acupuncture and moxibustion action derived from 2021 Nobel Prize in Physiology or Medicine

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Acupuncture and Herbal Medicine 2022年第1期2卷 1-8页

作者： Yi Guo Yongming Li Tianle xu Michael Xi Zhu zhifang xu Baomin Dou Yanwei Li Zhihan Chen Research Center of Experimental Acupuncture Science Tianjin University of Traditional Chinese MedicineTianjinChina School of Traditional Chinese Medicine Tianjin University of Traditional Chinese MedicineTianjinChina National Clinical Research Center for Chinese Medicine Acupuncture and Moxibustion TianjinChina American Traditional Chinese Medicine Society New YorkNYUSA Collaborative Innovation Center for Brain Science Department of Anatomy and PhysiologyShanghai Jiao Tong University School of MedicineShanghaiChina Department of Integrative Biology and Pharmacology The University of Texas Health Science Center at HoustonHoustonTXUSA School of Acupuncture&Moxibustion and Tuina Tianjin University of Traditional Chinese MedicineTianjinChina

The editorial board of Acupuncture and Herbal Medicine recently convened an academic seminar with a focus on studies regarding the mechanisms mediating acupuncture efficacy and moxibustion action inspired by the 2021 Nobel Prize in Physiology or Medicine.Specifically,Professor Bailong Xiao introduced the Nobel Prize for research on the mechanically activated Piezo ion channel,evaluating the structure of the Piezo channel and its physiological and pathological functions,and proposed a possible role for the Piezo channel in acupuncture mechanical stimulation.Professor Michael Xi Zhu introduced the discovery of the transient receptor potential(TRP)family,reporting that the therapeutic effects of Chinese medicine and acupuncture may be achieved via the TRP family,and that information regarding associations between the meridian and lymphatic systems may have important research and medical value.In addition,Professor Tianle xu reviewed the history of ion channel research,particularly the physiological and pharmacological effects of non-classical ion channels(eg,the acid sensing ion channel family)and pointed out that the characterization and neural circuits of acupuncture deqi manipulation are important for elucidating the mechanisms of acupuncture actions.Professor Yongming Li similarly proposed that the 2021 Nobel Prize may open the door to disclosing the histological basis of acupuncture and moxibustion and analyzing the main scientific concerns regarding the clinical translation of acupuncture and moxibustion from basic to translational research.Finally,Professor Yi Guo summarized the study progress of the acupoint microenvironment induced by acupuncture over the course of nearly 30 years and put forward the hypothesis that acupuncture may initiate the physical-chemical coupling network by activating ion channel receptors in acupoints via physical and mechanical stimulation.Therefore,we conclude that a primary achievement of the 2021 Nobel Prize in Physiology or Medicine is in helping interpret how acupuncture and

关键词： 2021 Nobel Prize in Physiology or Medicine Acupuncture Ion channel Moxibustion Piezo TRPV1

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Adenosine triphosphate mediates the pain tolerance effect of manual acupuncture at Zusanli(ST36) in mice

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Journal of Traditional Chinese Medicine 2024年第4期 660-669页

作者： LI Zhongzheng ZHAO Yadan Ma Weigang Zhang Yonglong xu zhifang XI Qiang LI Yanqi QIN Siru ZHANG Zichen WANG Songtao ZHAO xue LIU Yangyang GUO Yi GUO Yongming Research Center of Experimental Acupuncture Science Tianjin University of Traditional Chinese Medicine National Clinical Research Center for Chinese Medicine Acupuncture and Moxibustion Department of Acupuncture and Moxibustion Qingdao Hiser Hospital Affiliated of Qingdao University(Qingdao Traditional Chinese Medicine Hospital) School of Traditional Chinese Medicine Tianjin University of Traditional Chinese Medicine School of Acupuncture and Moxibustion and Tuina Tianjin University of Traditional Chinese Medicine

OBJECTIVE: To investigate the mechanisms behind the effects of acupuncture in Traditional Chinese Medicine,we delved into the adenosine triphosphate/peripheral purinergic P2X receptor 3(ATP/P2X3) receptor signaling system as an indicator of the body's energy state,commonly referred to as "Qi".METHODS: The tail-flick test was utilized to explore the impact of acupuncture on pain tolerance threshold(PTT)in mice, while also assessing adenosine(ADO) levels and adenylate energy charge(EC) at Zusanli(ST36). The study further investigated the dose-dependent effects of acupuncture on PTT and ADO levels at Zusanli(ST36).To shed light on the underlying mechanisms of acupuncture's effects, the study examined the impact of ATP, a P2X3 receptor antagonist, and adenosine disodium on PTT following acupuncture administration. RESULTS: Acupuncture at Zusanli(ST36) led to significant improvements in PTT in mice, with the most effective interventions being twirling for 2 min and needle retention for 28 min. These interventions also resulted in significant increases in ATP levels. The effects of acupuncture were further augmented by administration of different doses of ATP at Zusanli(ST36), and pretreatment with a P2X3 receptor antagonist decreased PTT. Adenylate EC peaked at 30 min after intraperitoneal injection of ATP, and pretreatment with various doses of i.p. ATP 30 min prior to acupuncture increased PTT in a dose-dependent manner. Additionally, pretreatment with an i.p. or intramuscular injection of adenosine disodium enhanced the effects of acupuncture. CONCLUSION: This research provides compelling evidence that ATP is involved in the regulation of PTT through acupuncture, revealing new avenues for achieving enhanced clinical outcomes.

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Spatiotemporal variations of nitrate sources and dynamics in a typical agricultural riverine system under monsoon climate

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Journal of Environmental Sciences 2020年第7期32卷 98-108页

作者： Hao Jiang Wenjing Liu Jiangyi Zhang Li Zhou Xiaode Zhou Ke Pan Tong Zhao Yuchen Wang zhifang xu Institute for Advanced Study Shenzhen UniversityShenzhen518060China College of Physics and Optoelectronic Engineering Shenzhen UniversityShenzhen 518060China Key Laboratory of Cenozoic Geology and Environment Institute of Geology and GeophysicsChinese Academy of SciencesBeijing 100029China CAS Center for Excellence in Life and Paleoenvironment Beijing 100044China University of Chinese Academy of Sciences Beijing 100049China State Key Laboratory of Biogeology and Environmental Geology China University of GeosciencesWuhan 430074China

Nitrogen pollution is a serious environmental issue in the Danjiangkou Reservoir region(DRR),the water source of the South-to-North Water Diversion Project of China.In this research,seasonal surveys and a bi-weekly time series survey were conducted in the Qihe River Basin,one of the most densely populated agricultural basins in the DRR.Hydrochemical compositions(NO3^-Cl^-),dual isotopes(δD-H2O,δ^18O-H2O,δ^15N-NO3^-,andδ^18O-NO3^-),and a Markov Chain Monte Carlo isotope mixing model were jointly applied to unravel the sources,migrations,and transformations of the nitrate(NO3^-)in the basin.It was revealed that the mixing between different sources was the main process controlling the isotopic compositions of the riverine NO3the upper-middle reaches.In contrast,denitrification occurred in the lower reaches.For the first time,the sources of NO3^-quantified at a basin scale in the DRR.Overall,the river transported 484.2 tons/year of NO3^-N to the reservoir,of which 32.6%,36.4%,28.0%,and 3.0%was from soil organic nitrogen,chemical fertilizer,residential sewage and atmospheric precipitation,respectively.The NO3^-N fluxes of the different sources were regulated by the monsoon climate and anthropogenic activities.For example,high precipitation and intense fertilization resulted in severe nonpoint source pollution.Denitrification thrived in soils and reservoirs in wet seasons.Temperature could regulate the migration,nitrification and denitrification processes.Based on the results,we suggest that the management strategies dealing with nitrogen pollution issue in the DRR should follow the specific spatiotemporal characteristics of NO3migration and transformation mechanisms.

关键词： Nitrate Source Dynamics Isotope MCMC mixing model

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气相色谱内标法测定白酒中甲醇含量的不确定度分析

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现代食品 2024年第5期30卷 160-162页

作者：许志芳中谱检测技术(山西)有限公司山西临汾043000

采用气相色谱内标法测定白酒中甲醇的含量。通过建立数学模型,分析实验过程中的不确定度来源,计算影响检测结果的各个不确定度分量,评定合成和扩展不确定度。结果表明,当白酒中甲醇含量为125.868 mg·L^(-1)时,扩展不确定度为5.764 mg·... 详细信息

采用气相色谱内标法测定白酒中甲醇的含量。通过建立数学模型,分析实验过程中的不确定度来源,计算影响检测结果的各个不确定度分量,评定合成和扩展不确定度。结果表明,当白酒中甲醇含量为125.868 mg·L^(-1)时,扩展不确定度为5.764 mg·L^(-1)(k=2)。

关键词：气相色谱法白酒甲醇不确定度

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针刺调控缺血性卒中后神经元线粒体的作用机制研究进展

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针刺研究 2024年第1期49卷 71-78页

作者：李昱萱张润琛程爱新马庆韬付天聪王冠然徐枝芳郭扬天津中医药大学第一附属医院天津300193 国家中医针灸临床医学研究中心天津300193 天津中医药大学实验针灸研究中心天津301617 天津市针灸学重点实验室天津300193 国家中医药管理局脑病针刺疗法重点研究室天津300000

针刺治疗缺血性卒中(IS)具有显著疗效。针刺治疗IS的作用与调控线粒体功能具有密切的联系。本文从线粒体结构、线粒体功能、线粒体质量控制、线粒体相关的细胞凋亡通路4个方面对线粒体在针刺治疗IS中的作用与相关机制进行综述,为针刺通... 详细信息

针刺治疗缺血性卒中(IS)具有显著疗效。针刺治疗IS的作用与调控线粒体功能具有密切的联系。本文从线粒体结构、线粒体功能、线粒体质量控制、线粒体相关的细胞凋亡通路4个方面对线粒体在针刺治疗IS中的作用与相关机制进行综述,为针刺通过调控神经元线粒体治疗IS提供理论依据,为今后深入开展相关研究提供参考。

关键词：缺血性卒中针刺线粒体线粒体功能障碍综述

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Near-Field Heat Transfer Enhancement of SiC-hBN-InSb Thermophotovoltaic System by Graphene Strong Coupling Effects

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Journal of Thermal Science 2024年第4期33卷 1409-1420页

作者： xu Zhiguo HU zhifang School of Mechanical Engineering Shanghai Jiao Tong University

Near-field thermophotovoltaic(NTPV) devices comprising a SiC-hBN-graphene emitter and a graphene-InSb cell with gratings are designed to enhance the performance of the NTPV systems.Fluctuational electrodynamics and rigorous coupled-wave analysis are employed to calculate radiative heat transfer fluxes.It is found that the NTPV systems with two graphene ribbons perform better due to the graphene strong coupling effects.The effects of graphene chemical potential are discussed.It is demonstrated that near-field radiative heat transfer of thermophotovoltaic devices is enhanced by the coupling of surface plasmon polaritons,surface phonon polaritons,hyperbolic phonon polaritons,and magnetic polaritons caused by the graphene strong coupling effects.Rabi splitting frequency of different polaritons is calculated to quantify the mutual interaction of graphene strong coupling effects.Finally,the effects of cell grating filling ratio are investigated.The excitation of magnetic polaritons is affected by the graphene ribbon and the cell filling ratio.This investigation provides a new explanation of the enhancement mechanism of graphene-assisted thermophotovoltaic systems and a novel approach for improving the output power of the near-field thermophotovoltaic system.

关键词： near-field radiative heat transfer thermophotovoltaics strong coupling effect multiple magnetic polaritons graphene-hbn heterostructures

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