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Frontiers of Environmental Science & Engineering 2024年第5期18卷 1-12页

作者： Jiamin hu Zhenwen Xie Jiane Zuo State Key Joint Laboratory of Environmental Simulation and Pollution Control School of EnvironmentTsinghua UniversityBeijing100084China Tsinghua Shenzhen International Graduate School Tsinghua UniversityShenzhen518055China

It has been confirmed that microplastics(MPs)are present in the environment.This study simulated secondary PE-MPs via aging and mechanical processes to evaluate their effects on Pak choi(Brassica rapa L.)over 21 d.Two common pollutants,dichlorodiphenyltrichloroethane(DDT)and naphthalene,were used in the combined toxicity tests.The results indicated that the growth of Pak choi was significantly inhibited after exposure to secondary PE-MPs,and the combined effects were antagonistic,owing to the adsorption capacity of secondary PE-MPs to DDT and naphthalene.Oxidative stress in Pak choi can be markedly affected,leading to oxidative damage to plant cells.The moisture content,soil bulk density,soil density,cation exchange capacity(CEC),and FDA hydrolase in the planted soils increased in the treated groups,and the TOC content changed significantly.We also found that the microbial composition of the soil in the DDT and naphthalene groups showed more significant alterations than that in the other groups.Alpha diversity analysis showed that species diversity increased in the combined groups but indicated a clear downward trend in the single MPs groups.This study suggests that secondary PE-MPs harm the growth of Pak choi and can change soil properties,revealing the harm to the ecosystem of MPs in the soil.

关键词： Secondary PE-MPs Combined effects Oxidative stress Soil properties Bacterial community

Changes in extreme high temperature warning indicators over China under different global warming levels

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Science China Earth Sciences 2024年第6期67卷 1895-1909页

作者： Yuxia ZHANG Ying SUN Ting hu Chinese Academy of Meteorological Sciences Beijing 100081China National Climate Center Laboratory for Climate StudiesChina Meteorological AdministrationBeijing 100081China

High temperature warning indicators play a pivotal role in meteorological departments,serving as crucial criteria for issuing warnings that guide both social production and daily life.Despite their importance,limited studies have explored the relationship between different global warming levels and changes in high temperature warning indicators.In this study,we analyze data from 2,419 meteorological stations over China and utilize the Coupled Model Intercomparison Project Phase 6(CMIP6)models to examine historical changes in high temperature warning indicators used by the China Meteorological Administration.We evaluate model performance and estimate future changes in these indicators using an annual cycle bias correction method.The results indicate that since 1961,the number of high temperature days(TX35d and TX40d)and length of season(TX40d and TX40l)with daily maximum temperature reaching or exceeding 35℃ and 40℃ have increased over China.The intensity of high temperatures(TXx)has strengthened and the geographical extent affected by high temperatures has expanded.In 2022,the occurrence of 40℃ high temperatures surges,with Eastern China experiencing a two-day increase in TX40d and an extended seasonal length in TX40l by over five days.While CMIP6 models have underestimated the high temperature indictors associated with 35℃ during historical periods,notable difference is not observed between the models and observations for TX40d and TX40l,given their rare occurrence.However,future projections,after bias correction,indicate that the increasing trends for 35℃ and 40℃ high temperature days and length of season become more pronounced than the raw projection,suggesting a more severe increase than that anticipated originally.As global warming intensifies,the high temperature days and length of season are projected to increase non-linearly,while the intensity of high temperatures is expected to increase linearly.For every 1℃ increase in global temperature,the intensity is projected to rise by approximately 1.4℃.The impa

关键词： Extreme high temperatures Meteorological warning CMIP6 Global warming levels Future projection

Tensor perturbations from bounce inflation scenario in f(Q)gravity

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Science China(Physics,Mechanics & Astronomy) 2024年第2期67卷 78-92页

作者： Kun hu Tanmoy Paul Taotao Qiu Institute of Astrophysics Central China Normal UniversityWuhan 430079China School of Physics Huazhong University of Science and TechnologyWuhan 430074China National Institute of Technology Jamshedpur Department of PhysicsJamshedpur 831014India

In this paper,we construct a bounce inflation cosmological scenario in the framework of the modified symmetric teleparallel gravity,namely f(Q)theory,and investigate the tensor perturbations therein.As is well-known,the tensor perturbations generated in the very early Universe(inflation and pre-inflation regions)can account for the primordial gravitational waves(PGWs)that are to be detected by the next generation of GW experiments.We discuss the stability condition of the tensor perturbations in the bounce inflation process and investigate in detail the evolution of the perturbation variable.The general form of the tensor power spectrum is obtained both for large as well as small scale modes.As a result,we show both kinds of modes(short or long wavelength modes),and the tensor spectrum may get a positive tilt in the parametric range where the tensor perturbation proves to be stable—this interestingly hints an enhancement of gravitational waves’amplitude in the background of the f(Q)bounce-inflation scenario.Moreover,we study the LQC-like scenario as a specific case of our model,in which,the primordial tensor power spectrum turns out to be nearly scale-invariant on both small and large scales.

关键词： bounce cosmology modified gravity cosmological perturbations

Coupled conditional nonlinear optimal perturbations and their application to ENSO ensemble forecasts

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Science China Earth Sciences 2024年第3期67卷 826-842页

作者： Wansuo DUAN Lei hu Rong FENG LASG Institute of Atmospheric PhysicsChinese Academy of SciencesBeijing 100029China University of Chinese Academy of Sciences Beijing 100049China

Limitations are existed in current ensemble forecasting initial perturbation methods for describing the interactions among various spheres of the Earth system. In this study, a new method is proposed, namely, the coupled conditional nonlinear optimal perturbation(C-CNOP) method, which incorporates multisphere interactions much appropriately. The El Nino-Southern Oscillation(ENSO) is a typical ocean-atmosphere “coupling”(or “interaction”) phenomenon. The C-CNOP method is applied to ensemble forecasting of ENSO. It is demonstrated that the C-CNOP method can generate coupled initial perturbations(CPs) that appropriately consider initial ocean-atmosphere coupling uncertainty for ENSO ensemble forecasts. Results reveal that the CPs effectively improve the ability of ENSO ensemble-mean forecasts in both temporal variability of Nio3.4 sea surface temperature anomalies(SSTAs) and spatial variability of ENSO mature-phase SSTAs. Notably, despite the weakest ocean-atmosphere coupling strength in the tropical Pacific occurring during the boreal spring and summer, CPs still capture the uncertainties of this weak coupling when ENSO predictions are initialized at these seasons. This performance of CPs significantly suppresses the rapid increase of ENSO prediction errors due to the high ocean-atmosphere coupling instability during these seasons, and thus effectively extends the lead time of skillful ENSO forecasting. Hence, the C-CNOP method is a suitable initial perturbation approach for ENSO ensemble forecast that can describe initial ocean-atmosphere coupling uncertainty. It is expected that the CCNOP method plays a significant role in predictions of other high-impact climate phenomena, and even future Earth system predictions.

关键词： Ensemble forecast Multisphere interaction Initial perturbations ENSO

Corrosion behaviors and kinetics of nanoscale zero-valent iron in water:A review

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Journal of Environmental Sciences 2024年第1期135卷 391-406页

作者： Chenliu Tang Xingyu Wang Yufei Zhang Nuo Liu Xiang hu Research Group of Water Pollution Control and Water Reclamation College of Chemical EngineeringBeijing University of Chemical TechnologyBeijing 100029China Shanghai Collaborative Innovation Centre for WEEE Recycling School of Resources and Environmental EngineeringShanghai Polytechnic UniversityShanghai 201209China

Knowledge on corrosion behaviors and kinetics of nanoscale zero-valent iron(nZVI)in aquatic environment is particularly significant for understanding the reactivity,longevity and stability of nZVI,as well as providing theoretical guidance for developing a cost-effective nZVI-based technology and designing large-scale applications.Herein,this review gives a holistic overview on the corrosion behaviors and kinetics of nZVI in water.Firstly,Eh-pH diagram is introduced to predict the thermodynamics trend of iron corrosion.The morphological,structural,and compositional evolution of(modified-)nZVI under different environmental conditions,assisted with microscopic and spectroscopic evidence,is then summarized.Afterwards,common analytical methods and characterization technologies are categorized to establish time-resolved corrosion kinetics of nZVI in water.Specifically,stable models for calculating the corrosion rate constant of nZVI as well as electrochemical methods for monitoring the redox reaction are discussed,emphasizing their capabilities in studying the dynamic iron corrosion processes.Finally,in the future,more efforts are encouraged to study the corrosion behaviors of nZVI in long-term practical application and further build nanoparticles with precisely tailored properties.We expect that our work can deepen the understanding of the nZVI chemistry in aquatic environment.

关键词： Nanoscale zero-valent iron(nZVI) Corrosion behaviors Corrosion kinetics nZVI evolution

Carbonation of Dicalcium Silicate Enhanced by Ammonia Bicarbonate and Its Mechanism

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Journal of Wuhan University of Technology(Materials Science) 2024年第1期39卷 69-74页

作者：周浩刘鹏 WANG Fazhou hu Chuanlin School of Chemistry Chemical Engineering and Life ScienceWuhan University of TechnologyWuhan 430070China State Key Laboratory of Silicate Materials for Architectures Wuhan University of TechnologyWuhan 430070China

The strength development law of γ-type dicalcium silicate (γ-C_(2)S) under different carbonation processes was investigated,and the carbonation mechanism of γ-C_(2)S under the action of NH_(4)HCO_(3) was clarified by using a wide range of test methods,including XRD and SEM.A method of saturated NH_(4)HCO_(3) solution as a curing agent was identified to improve the carbonation efficiency and enhance the carbonation degree of γ-C_(2)S,and then a high-strength carbonated specimen was obtained.Microhardness analysis and SEM morphology analysis were conducted on the carbonised specimens obtained under atmospheric pressure carbonisation conditions using the curing agent.It was found that γ-C_(2)S could perform carbonisation well under atmospheric pressure,which promoted the carbonisation efficiency and decreased the carbonisation cost simultaneously.Therefore,a new carbonisation process solution was proposed for the rapid carbonisation of γ-C_(2)S.

关键词： type dicalcium silicate carbonization process curing agent atmospheric carbonization

Circ_0003855 involvement of esophageal cancer progression through miR-622/FLOT1

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Oncology Research 2024年第5期32卷 925-931页

作者： JINGJING TIAN XIBAO hu XINRONG ZHANG Department of Gastroenterology Tianjin Nankai HospitalTianjin300100China Department of Digestive Medicine First Teaching Hospital of Tianjin University of Traditional Chinese MedicineTianjin300100China

To confirm the relationship between Circ_0003855 and EC,we purchased the human esophageal carcinoma cell line Eca109 and normal human esophageal epithelial cells HEEC,and the expression levels of Circ_0003855,miR-622,and FLOT1 were detected.The results show that Circ_0003855 and FLOT1 were highly expressed in Eca109 cells,while miR-622 was lowly expressed(p0.05).Synthesizing the results of these experiments above,we believe that interfering with the expression of Circ_0003855 can inhibit the activity of EC cells,and its mechanism is related to miR-622 and FLOT1.

关键词： Circ_0003855 miR-622 FLOT1 Esophageal cancer Cell proliferation

Advanced Sensors Towards Ubiquitous Power Internet of Things

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CSEE Journal of Power and Energy Systems 2024年第3期10卷 871-890页

作者： Jinliang He Zhifei Han Jun hu Department of Electrical Engineering Tsinghua UniversityBeijing 100084China IEEE CSEE

The ubiquitous power Internet of Things(UPIoT)uses modern information technology and advanced communication technologies to realize interconnection and human-computer interaction in all aspects of the power system.UPIoT has the characteristics of comprehensive state perception and efficient information processing,and has broad application prospects for transformation of the energy industry.The fundamental facility of the UPIoT is the sensor-based information network.By using advanced sensors,Wireless Sensor Networks(WSNs),and advanced data processing technologies,Internet of Things can be realized in the power system.In this paper,a framework of WSNs based on advanced sensors towards UPIoT is proposed.In addition,the most advanced sensors for UPIoT purposes are reviewed,along with an explanation of how the sensor data obtained in UPIoT is utilized in various scenarios.

关键词： Advanced sensors ubiquitous power Internet of Things wireless sensor networks

Initial costates derived by near-optimal reference sequence and least-squares method

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Chinese Journal of Aeronautics 2024年第5期37卷 377-391页

作者： Shaozhao LU Yao ZHANG Quan hu School of Aerospace Engineering Beijing Institute of TechnologyBeijing 100081China

In this paper,we present a novel initial costates solver for initializing time-optimal trajectory problems in relative motion with continuous low thrust.The proposed solver consists of two primary components:training a Multilayer Perceptron(MLP)for generating reference sequence and Time of Flight(TOF)to the target,and deriving a system of linear algebraic equations for obtaining the initial costates.To overcome the challenge of generating training samples for the MLP,the backward generation method is proposed to obtain five different training databases.The training database and sample form are determined by analyzing the input and output correlation using the Pearson correlation coefficient.The best-performing MLP is obtained by analyzing the training results with various hyper-parameter combinations.A reference sequence starting from the initial states is obtained by integrating forward with the near-optimal control vector from the output of MLP.Finally,a system of linear algebraic equations for estimating the initial costates is derived using the reference sequence and the necessary conditions for optimality.Simulation results demonstrate that the proposed initial costates solver improves the convergence ratio and reduce the function calls of the shooting function.Furthermore,Monte-Carlo simulation illustrates that the initial costates solver is applicable to different initial velocities,demonstrating excellent generalization ability.

关键词： Relative motion Expanding training database Multilayer perceptron Initial costates Least-squares method

Analysis of Sea Surface Temperature Cooling in Typhoon Events Passing the Kuroshio Current

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Journal of Ocean University of China 2024年第2期23卷 287-303页

作者： hu Yuyi SHAO Weizeng SHEN Wei ZUO Juncheng JIANG Tao hu Song College of Marine Sciences Shanghai Ocean UniversityShanghai 201306China East China Sea Environment Monitoring Ministry of Natural ResourcesShanghai 201206China China Waterborne Transport Research Institute Ministry of TransportBeijing 100088China

The aim of this study is to investigate the sea surface temperature(SST) cooling as typhoons pass the Kuroshio Current.A numerical circulation model,denoted as the Stony Brook Parallel Ocean Model(sbPOM),was used to simulate the SST,which includes four wave-induced effect terms(i.e.,radiation stress,nonbreaking waves,Stokes drift,and breaking waves) simulated using the third-generation wave model,called WAVEWATCH-Ⅲ(WW3).The significant wave height(SWH) measurements from the Jason-2 altimeter were used to validate the WW3-simulated results,yielding a root mean square error(RMSE) of less than 0.50 m and a correlation coefficient(COR) of approximately 0.93.The water temperature measured from the Advanced Research and Global Observation Satellite was applied to validate the model simulation.Accordingly,the RMSE of the SST is 0.92℃ with a COR of approximately 0.99.As revealed in the sbPOM-simulated SST fields,a reduction in the SST at the Kuroshio Current region was observed as a typhoon passed,although the water temperature of the Kuroshio Current is relatively high.The variation of the SST is consistent with that of the current,whereas the maximum SST lagged behind the occurrence of the peak SWH.Moreover,the Stokes drift plays an important role in the SST cooling after analyzing four wave-induced terms in the background of the Kuroshio Current.The sensitivity experiment also showed that the accuracy of the water temperature was significantly reduced when including breaking waves,which play a negative role in the inside part of the ocean.The variation in the mean mixing layer depth(MLD) showed that a typhoon could enhance the mean MLD in the Kuroshio Current area in September and October,whereas a typhoon has little influence on the mean MLD in the Kuroshio Current area in May.Moreover,the mean MLD rapidly decreased with the weakening of the strong wind force and wave-induced effects when a typhoon crossed the Kuroshio Current.

关键词： typhoon wave sea surface temperature Kuroshio Current