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On the topological surface states of the intrinsic magnetic topological insulator Mn-Bi-Te family

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National Science Review 2024年第2期11卷 50-64页

作者： Yuan Wang Xiao-Ming Ma Zhanyang Hao Yongqing Cai Hongtao rong Fayuan Zhang Weizhao chen chengcheng Zhang Junhao Lin Yue Zhao chang Liu Qihang Liu Chaoyu chen Shenzhen Institute for Quantum Science and Engineering(SIQSE)and Department of Physics Southern University of Science and Technology(SUSTech)

We review recent progress in the electronic structure study of intrinsic magnetic topological insulators（MnBi2Te4）·（Bi2Te3）n（n = 0, 1, 2, 3） family. Specifically, we focus on the ubiquitously（nearly）gapless behavior of the topological Dirac surface state observed by photoemission spectroscopy, even though a large Dirac gap is expected because of surface ferromagnetic order. The dichotomy between experiment and theory concerning this gap behavior is perhaps the most critical and puzzling question in this frontier. We discuss various proposals accounting for the lack of magnetic effect on the topological Dirac surface state, which are mainly categorized into two pictures, magnetic reconfiguration and topological surface state redistribution. Band engineering towards opening a magnetic gap of topological surface states provides great opportunities to realize quantized topological transport and axion electrodynamics at higher temperatures.

关键词： intrinsic magnetic topological insulator topological surface states magnetic gap magnetic reconfiguration topological surface state redistribution van der Waals spacing expansion

A passive sampler for synchronously measuring inorganic and organic pollutants in sediment porewater:Configuration and field application

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Journal of Environmental Sciences 2024年第2期136卷 201-212页

作者： Pei Lei Mingying chen Nan rong Wenzhong Tang Hong Zhang School of Environment Nanjing Normal UniversityNanjing 210023China State Key Laboratory of Environmental Aquatic Chemistry Research Center for Eco-Environmental SciencesChinese Academy of SciencesBeijing 100085China South China Institute of Environmental Sciences Ministry of Ecology and EnvironmentGuangzhou 510530China State Environmental Protection Key Laboratory of Water Environmental Simulation and Pollution Control Guangzhou 510530China University of Chinese Academy of Sciences Beijing 100049China

In situ measurement of multiple pollutants coexisting in sediment porewater is an essential step in comprehensively assessing the bioavailability and risk of pollutants,but to date,this needs to be better developed.In this study,a passive sampler,consisting of an“I-shaped”supporting frame and inorganic/organic sampling units,incorporating equilibrium dialysis theory and kinetic/equilibrium sorption principle,was developed for the synchronous measurement of inorganic(e.g.,phosphorus and metal(loid)s)and organic pollutants(e.g.,parent and substituted PAHs).The equilibrium time and sampling rates were explored in laboratory tests to support in situ application.Profiles of pollutants in porewater within a vertical resolution of centimeters,i.e.,1 cm and 2 cm for inorganic and organic pollutants,respectively,were obtained by field deployment of the sampler for further estimation of diffusive fluxes across the sediment-water interface.The results suggested that the role of sediments for a specific pollutant may change(e.g.,from“sink”to“source”)during the sampling time.This study demonstrated the feasibility of synchronous measurement of inorganic and organic pollutants in sediment porewater by the passive sampler.In addition,it provided new insight for further investigation into the combined pollution effects of various pollutants in sediments.

关键词： Passive sampling Bioavailability Polycyclic aromatic hydrocarbons Combined pollution Diffusive flux

Spin-orbit interaction induced Casimir-Lifshitz torque between two-dimensional electron gases

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Science China(Physics,Mechanics & Astronomy) 2024年

作者： Jia-Nan rong Liang chen Kai chang State Key Laboratory of Superlattices and Microstructures Institute of Semiconductors Chinese Academy of Sciences College of Materials Science and Opto-electronic Technology University of Chinese Academy of Sciences School of Mathematics and Physics North China Electric Power University School of Physics Zhejiang University

We investigate theoretically the Casimir interaction between two parallel two-dimensional electron gases (2DEGs) with Rashba and Dresselhaus spin-orbit interactions (SOIs), based on the quantum field theory. We derive an analytical expression for the polarization tensor and obtain the solution to the motion equation of the electromagnetic (EM) field. We calculate the CasimirLifshitz torque (CLT) between two parallel 2DEGs with Rashba and Dresselhaus SOIs, which can be tuned by changing the relative strength between two SOIs. The anisotropic Casimir energy between 2DEGs caused by the interplay between the SOIs of 2DEGs offers a new origin of CLT and a new type of optoelectronic device.

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Atomically Dispersed Ruthenium Catalysts with Open Hollow Structure for Lithium-Oxygen Batteries

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Nano-Micro Letters 2024年第2期16卷 154-164页

作者： Xin chen Yu Zhang chang chen Huinan Li Yuran Lin Ke Yu Caiyun Nan chen chen Beijing Advanced Innovation Center for Materials Genome Engineering Institute of Solid State ChemistryUniversity of Science and Technology BeijingBeijing 100083People’s Republic of China Engineering Research Center of Advanced Rare Earth Materials Department of ChemistryTsinghua UniversityBeijing 100084People’s Republic of China Beijing Key Laboratory of Energy Conversion and Storage Materials Institution College of ChemistryBeijing Normal UniversityBeijing 100875People’s Republic of China

Lithium–oxygen battery with ultrahigh theoretical energy density is considered a highly competitive next-generation energy storage device,but its practical application is severely hindered by issues such as difficult decomposition of discharge products at present.Here,we have developed N-doped carbon anchored atomically dispersed Ru sites cathode catalyst with open hollow structure(h-RuNC)for Lithium–oxygen battery.On one hand,the abundance of atomically dispersed Ru sites can effectively catalyze the formation and decomposition of discharge products,thereby greatly enhancing the redox kinetics.On the other hand,the open hollow structure not only enhances the mass activity of atomically dispersed Ru sites but also improves the diffusion efficiency of catalytic molecules.Therefore,the excellent activity from atomically dispersed Ru sites and the enhanced diffusion from open hollow structure respectively improve the redox kinetics and cycling stability,ultimately achieving a high-performance lithium–oxygen battery.

关键词： Atomically dispersed Open hollow structure Discharge product Lithium Oxygen battery

Association between body mass index and in vitro fertilization/intra-cytoplasmic sperm injection outcomes: An analysis of 15,124 normal ovarian responders in China

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中华医学杂志(英文版) 2024年第7期137卷 837-845页

作者： Zheng Danlei Wang Yuanyuan chen Lixue Zeng Lin Li rong Department of Obstetrics and Gynecology Center for Reproductive Medicine Peking University Third Hospital Beijing 100191 China Research Center of Clinical Epidemiology

Background: High body mass index (BMI) results in decreased fecundity, and women with high BMI have reduced rates of clinical pregnancy and live birth inin vitro fertilization/intra-cytoplasmic sperm injection (IVF/ICSI). Meanwhile, ovarian responses show great heterogeneity in patients with a high BMI. This study aimed to analyze the effects of a high BMI on IVF/ICSI outcomes in the Chinese female with normal ovarian response.Methods: We performed a retrospective cohort study comprising 15,124 patients from the medical record system of the Reproductive Center of Peking University Third Hospital, with 3530 (23.3%) in the overweight group and 1380 (9.1%) in the obese group, who had a normal ovarian response (5-15 oocytes retrieved) and underwent fresh embryo transfer (ET) cycles from January 2017 to December 2018, followed by linked frozen-thawed embryo transfer (FET) cycles from January 2017 to December 2020. Cumulative live birth rate (CLBR) was used as the primary outcome. Furthermore, a generalized additive model was applied to visually illustrate the curvilinear relationship between BMI and the outcomes. We used a decision tree to identify the specific population where high BMI had the greatest effect on IVF/ICSI outcomes.Results: High BMI was associated with poor IVF/ICSI outcomes, both in cumulative cycles and in separate fresh ET or FET cycles. In cumulative cycles, compared with the normal weight group, obesity was correlated with a lower positive pregnancy test rate (adjusted odds ratio [aOR]: 0.809, 95% confidence interval [CI]: 0.682-0.960), lower clinical pregnancy rate (aOR: 0.766, 95% CI: 0.646-0.907), lower live birth rate (aOR: 0.706, 95% CI: 0.595-0.838), higher cesarean section rate (aOR: 2.066, 95% CI: 1.533-2.785), and higher rate of large for gestational age (aOR: 2.273, 95% CI: 1.547-3.341). In the generalized additive model, we found that CLBR declined with increasing BMI, with 24 kg/m2 as an inflection point. In the decision tree, BMI only made a difference in the population aged ≤34.5 yea

关键词： Obesity Body mass index In vitro fertilization Live birth Decision trees Normal ovarian response

Identification of high oxygen-consuming substances in stormwater drainage systems illicitly connected with sewage system

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Journal of Environmental Sciences 2024年第4期138卷 132-140页

作者： chen Xu Zuxin Xu Wenhai Chu Shanshan Wu rong Xiao Lei Su State Key Laboratory of Pollution Control and Resource Reuse College of Environmental Science and EngineeringTongji UniversityShanghai 200092China Ministry of Education Key Laboratory of Yangtze River Water Environment Tongji UniversityShanghai 200092China Guangzhou Resource Environmental Protection Technology Co. Ltd.Guangzhou 510030China

The dissolved oxygen content in water is an important indicator for assessing the quality of the water environment,and maintaining a certain amount of dissolved oxygen is essential for the healthy development of the ecological environment.When a water body is anoxic,the activity of anaerobic microorganisms increases and organic matter is decomposed to produce a large number of blackening and odorizing substances,resulting in black and odorous water bodies,which is a very common and typical phenomenon in China.Presently,there is still a relatively universal occurrence of illicitly connected stormwater and sewage pipes in the urban drainage pipe network in China,which makes oxygen-consuming substances be directly discharged into rivers through stormwater pipes and consume the dissolved oxygen in the water bodies,resulting in an oxygen deficiency of the water.This induces seasonal or year-round black and stink phenomena in urban rivers.Hence,identifying high oxygen-consuming substances,which lays the foundation for the subsequent removal of oxygen-consuming substances,is essential.Through a series of comparisons of water quality indicators and analysis of organic characteristics,it was found that the oxygen consumption capacity of domestic sewage was higher than that of industrial wastewater in the selected area of this study,and the oxygen-consuming substances of domestic sewage were small molecular amino acids.By comparing 20 conventional free amino acids,it was found that seven of them consumed oxygen easily,and compared with chemical oxygen consumption,biological oxygen consumption was in a leading position.

关键词： Urban drainage system Oxygen-consuming substances Domestic sewage Amino acid

Residual levels and health risk assessment of trace metals in Chinese resident diet

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Journal of Environmental Sciences 2024年第2期136卷 451-459页

作者： Yubing Dai Shuai Sun rong Cao Haijun Zhang Jiping chen Ningbo Geng CAS Key Laboratory of Separation Science for Analytical Chemistry Dalian Institute of Chemical PhysicsChinese Academy of SciencesDalian 116023China Shenyang Pharmaceutical University Shenyang 110016China University of Chinese Academy of Sciences Beijing 100049China

Large-scale metal contamination across the food web is an intractable problem due to increasing pollutant emissions,atmospheric transport,and dry and wet deposition of elements.The present study focus on several trace metals that are rarely studied but have special toxicity,including tin(Sn),antimony(Sb),gold(Au),hafnium(Hf),palladium(Pd),platinum(Pt),ruthenium(Ru),tellurium(Te)and iridium(Ir).We investigated trace metals residues and distribution characteristics,and further evaluated the potential health risks from major daily food intakes in 33 cities in China.Sn,Sb,Ir,Hf,and Au were frequently detected in food samples with the concentrations ranged from ND(not detected)to 24.78μg/kg ww(wet weight).Eggs exhibited the highest residual level of all detected metals(13.70±14.70μg/kg ww in sum),while the lowest concentrations were observed in vegetables(0.53±0.17μg/kg ww in sum).Sn accounting for more than 50%of the total trace metals concentration in both terrestrial and aquatic animal origin foods.In terrestrial plant origin foods,Sn and Ir were the most abundant elements.Hf and Au were the most abundant elements in egg samples.In addition,Sb and Ir showed a clear trophic dilution effect in terrestrial environments,while in aquatic ecosystems,Sn,Hf,and Au exhibited obvious trophic amplification effects.The calculated average estimated daily intake(EDI)via food consumption in five regions of China was 0.09μg/(kg·day),implying the health risk of aforementioned elements was acceptable.

关键词： Trace metals Accumulation characteristics Dietary exposure Estimated daily intake(EDI)

Self-adaptive gas flow and phase change behaviors during hydrate exploitation by alternate injection of N2 and CO2

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Petroleum Science 2024年第3期21卷 2120-2129页

作者： Bo-Jian Cao Yi-Fei Sun Hong-Nan chen Jin-rong Zhong Ming-Long Wang Ming Wang chang-Yu Sun Guang-Jin chen State Key Laboratory of Heavy Oil Processing China University of Petroleum School of Chemistry and Chemical Engineering Changsha University of Science & Technology

Since hydrate resources play a part of the stratigraphic framework structure in sediments,establishing a safe and economic method for hydrates exploitation remains the primary challenge to this day.Among the proposed methods,the spontaneous displacement of CH4from hydrate cages by CO2seems to be a perfect mechanism to address gas production and CO2storage,especially in today's strong demand for carbon reduction and replacing clean energy.After extensive lab researches,in the past decade,injecting a mixture of CO2and small molecule gas has become a key means to enhance displacement efficiency and has great potential for application.However,there is a lack of in-depth research on gas flow in the reservoir,while the injected gas always passes through low-saturated hydrate areas with high permeability and then occurs gas channel in a short term,finally resulting in the decreases in gas production efficiency and produced gas quality.Therefore,we explored a new injection-production mode of alternate injection of N2and CO2in order to fully coordinate the advantages of N2in enhanced hydrate decomposition and CO2in solid storage and heat compensation.These alternate "taking" and "storing" processes perfectly repair the problem of the gas channel,achieving self-regulation effect of CH4recovery and CO2storage.The 3-D experimental results show that compared to the mixed gas injection,CH4recovery is increased by>50% and CO2storage is increased by>70%.Additionally,this alternate injection mode presented a better performance in CH4concentration of produced gas and showed outstanding N2utilization efficiency.Further,we analyzed its self-adaptive gas flow mechanism and proposed an application model of "one injection and multiple production".We look forward to this study accelerating the application of CO2-CH4replacement technology.

关键词： Hydrate Replacement CH 4 recovery CO 2 storage Reservoir remediation

Neuroimmune interactions and their roles in neurodegenerative diseases

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Fundamental Research 2024年第2期4卷 251-261页

作者： Bai-rong chen Ting Wu Ting-Hui chen Yun Wang Neuroscience Research Institute and Department of Neurobiology School of Basic Medical SciencesKey Laboratory for NeuroscienceMinistry of Education/National Health Commission and State Key Laboratory of Natural and Biomimetic DrugsPeking UniversityBeijing 100083China PKU-IDG/McGovern Institute for Brain Research Peking UniversityBeijing 100871China

The nervous system possesses bidirectional,sophisticated and delicate communications with the immune system.These neuroimmune interactions play a vitally important role in the initiation and development of many disorders,especially neurodegenerative diseases.Although scientific advancements have made tremendous progress in this field during the last few years,neuroimmune communications are still far from being elucidated.By organizing recent research,in this review,we discuss the local and intersystem neuroimmune interactions and their roles in Alzheimer’s disease,Parkinson’s disease and amyotrophic lateral sclerosis.Unveiling these will help us gain a better understanding of the process of interplay inside the body and how the organism maintains homeostasis.It will also facilitate a view of the diseases from a holistic,pluralistic and interconnected perspective,thus providing a basis of developing novel and effective methods to diagnose,intervene and treat diseases.

关键词： Nervous system Immune system Neuroimmune interactions Alzheimer’s disease Parkinson’s disease Amyotrophic lateral sclerosis