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research on ozone formation sensitivity based on observational methods:Development history,methodology,and application and prospects in China

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Journal of Environmental Sciences 2024年第4期138卷 543-560页

作者： Wanghui Chu Hong Li Yuanyuan Ji Xin Zhang Likun Xue Jian Gao Cong An State Key Laboratory of Environmental Criteria and Risk Assessment Chinese Research Academy of Environmental SciencesBeijing 100012China Environment research Institute Shandong UniversityQingdao 266237China

Observation-based method for O_(3)formation sensitivity research is an important tool to analyze the causes of ground-level O_(3)pollution,which has broad application potentials in determining the O_(3)pollution formation mechanism and developing prevention and control *** paper outlined the development history of research on O_(3)formation sensitivity based on observational methods,described the principle and applicability of the methodology,summarized the relative application results in China and provided recommendations on the prevention and control of O_(3)pollution in China based on relevant study results,and finally pointed out the shortcomings and future development prospects in this field in *** overview study showed that the O_(3)formation sensitivity in some urban areas in China in recent years presented a gradual shifting tendency from the VOC-limited regime to the transition regime or the NO_(x)-limited regime due to the implementation of the O_(3)precursors emission reduction policies;O_(3)pollution control strategies and precursor control countermeasures should be formulated based on local conditions and the dynamic control capability of O_(3)pollution control measures should be *** are still some current deficiencies in the study field in ***,it is recommended that a stereoscopic monitoring network for atmospheric photochemical components should be further constructed and improved;the atmospheric chemical mechanisms should be vigorously developed,and standardized methods for determining the O_(3)formation sensitivity should be established in China in the near future.

关键词： Observation-based method Ozone formation sensitivity Ozone pollution prevention and control VOCs NO_(x) OBM

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A multiwavelength view of a classical T Tauri star CV Cha

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research in Astronomy and Astrophysics 2019年第1期19卷 75-86页

作者： Jeewan Chandra Pandey Subhajeet Karmakar Arti Joshi Saurabh Sharma Shashi Bhushan Pandey Anil Kumar Pandey Aryabhatta research Institute of observational Sciences (ARIES)

Using long-term optical, ultraviolet(UV) and X-ray data, we present a study of a classical T Tauri star CV Cha. The V-band light curve obtained from the All Sky Automated Survey(ASAS) shows short as well as long-term variability. The short-term variability could be due to rotational modulation of CV Cha. We derive the rotational period of 3.714 ± 0.001 d for CV Cha. UV light curves obtained from Swift also show the variations. X-ray light curves from XMM-Newton and Swift do not show any significant short as well as long-term variability. However, the light curve from Chandra appears to be variable, which could be due to the emergence of flaring activities. X-ray spectra from all observations are explained well by the single temperature plasma of 0.95 keV with X-ray luminosity of 1030.4erg s-1in the 0.5–7.5 keV energy band. It appears that variability in optical and UV bands could be due to the presence of both hot and cool spots on the surface, while X-ray emission is dominated by magnetic processes.

关键词： stars:activity stars:individual(CV Cha) stars:pre-main sequence stars:variable:T Tauri X-ray:stars

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Assessment of corrected time-step method for nominal ionospheric gradient calculation: A comparative analysis with spatial approaches

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Earth and Planetary Physics 2024年第4期8卷 641-649页

作者： Slamet Supriadi Prayitno Abadi Susumu Saito Harry Bangkit Dwiko Unggul Prabowo Adi Purwono Ginaldi Ari Nugroho research Center for Smart Mechatronics National Research and Innovation Agency(BRIN)BandungIndonesia research Center for Climate and Atmosphere BRINBandungIndonesia School of Electrical Engineering Telkom UniversityKab.BandungIndonesia Electronic Navigation research Institute National Institute of MaritimePort and Aviation TechnologyTokyoJapan research Center for Space BRINBandungIndonesia

The effect of ionospheric delay on the ground-based augmentation system under normal conditions can be mitigated by determining the value of the nominal ionospheric gradient(σvig).The nominal ionospheric gradient is generally obtained from Continuously Operating Reference Stations data by using the spatial single-difference method(mixed-pair,station-pair,or satellite-pair)or the temporal single-difference method(time-step).The time-step method uses only a single receiver,but it still contains ionospheric temporal *** introduce a corrected time-step method using a fixed-ionospheric pierce point from the geostationary equatorial orbit satellite and test it through simulations based on the global ionospheric *** also investigate the effect of satellite paths on the corrected time-step method in the region of the equator,which tends to be in a more north–south direction and to have less coverage for the east–west ionospheric *** study also addresses the limitations of temporal variation correction coverage and recommends using only the correction from *** processes are developed under simulations because observational data are still difficult to *** findings demonstrate that the corrected time-step method yieldsσvig values consistent with other approaches.

关键词： ground-based augmentation system nominal ionospheric gradient time-step correction global ionospheric model

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Clinical research linking Traditional Chinese Medicine constitution types with diseases:a literature review of 1639 observational studies

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Journal of Traditional Chinese Medicine 2020年第4期40卷 690-702页

作者： Liang Xue Wang Qi Jiang Zeqiang Li Zhuqing Zhang Mengxing Yang Peiying Wang Xin Wang Yanqiu Qin Yuehua Li Tianxing Zhang Tianyi Wang Yi Sun Jianxiang Li Yusi Luo Hui Li Lingru Center for Studies in Constitution research and Reproductive Sciences of Traditional Chinese Medicine Beijing University of Chinese MedicineBeijing 100029China Institute for Tibetan Medicine China Tibetology Research CenterBeijing 100101China

OBJECTIVE:To analyze clinical studies on correlations between Traditional Chinese Medicine(TCM)body constitution types and diseases published in the past 10 years,and to provide an evidence base to support the use of such correlations for health maintenance and disease ***:We searched five databases for the period April 2009 to December 2019:China National Knowledge Infrastructure Database,Wanfang Database,China Science and Technology Journal Database,PubMed and *** types of observational studies on correlation between constitution types and diseases were included:cross-sectional,case-control and cohort *** statistical methods were employed for data ***:A total of 1639 clinical studies were identified:1452(88.59%)cross-sectional studies,115(7.02%)case-control studies and 72(4.39%)cohort studies covering 30 regions of China and five other countries(Malaysia,South Korea,Singapore,Thailand and France).The collection of studies comprised 19 disease categories and 333 different *** 10 most commonly studied diseases were hypertension,diabetes,stroke,coronary atherosclerotic heart disease(CAHD),sleep disorders,neoplasm of the breast,dysmenorrhea,fatty liver disease,chronic viral hepatitis B and *** found high distributions for each biased constitution type in different patient populations as follows:Qi-deficiency constitution in stroke,diabetes,chronic obstructive pulmonary disease,acquired immunodeficiency syndrome and hypertension;Yang-deficiency constitution in female infertility,osteoporosis,irritable bowel syndrome,gonarthrosis and dysmenorrhea;Yin-deficiency constitution in hypertension,diabetes,constipation,female climacteric states and osteoporosis;phlegm-dampness constitution in hypertension,stroke,fatty liver disease,diabetes and metabolic syndrome;damp-heat constitution in acne,chronic gastritis,chronic viral hepatitis B,human papillomavirus infection and hyperuricemia;blood-stasis constit

关键词： Body constitution Medicine,Chinese traditional Clinical study Review

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Duration distributions for different softness groups of gamma-ray bursts

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Science China(Physics,Mechanics & Astronomy) 2010年第7期53卷 1375-1382页

作者： GUPTA A.C. Aryabhatta research Institute of observational Sciences(ARIES) Manora PeakNainital-263129India

Gamma-ray bursts(GRBs) are divided into two classes according to their *** investigate if the softness of bursts plays a role in the conventional classification of the *** employ the BATSE(Burst and Transient Source Experiment) catalog and analyze the duration distributions of different groups of GRBs associated with distinct *** analysis reveals that the conventional classification of GRBs with the duration of bursts is influenced by the softness of the *** exists a bimodality in the duration distribution of GRBs for each group of bursts and the time position of the dip in the bimodality histogram shifts with the softness *** findings suggest that the conventional classification scheme should be modified by separating the two well-known populations in different softness groups,which would be more reasonable than doing so with a single *** to the relation between the dip position and the softness parameter,we get an empirical function that can roughly set apart the short-hard and long-soft bursts:SP =(0.100 ± 0.028) T-(0.85 0.18) 90,± where SP is the softness parameter adopted in this paper.

关键词： gamma-rays bursts:methods data analysis:methods statistical

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Imprints of ultralight axions on the gravitational wave and pulsar timing measurement

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Science China(Physics,Mechanics & Astronomy) 2024年第1期67卷 23-29页

作者： Ning Xie Fa Peng Huang MOE Key Laboratory of TianQin Mission TianQin Research Center for Gravitational Physics&School of Physics and AstronomyFrontiers Science Center for TianQinGravitational Wave Research Center of CNSASun Yat-sen University(Zhuhai Campus)Zhuhai 519082China

The axion or axion-like particle motivated from a natural solution of strong CP problem or string theory is a promising dark matter *** study the new observational effects of ultralight axion-like particles by the space-borne gravitational wave detector and the radio *** the neutron star-black hole binary as an example,we demonstrate that the gravitational waveform could be obviously modified by the slow depletion of the axion cloud around the black hole formed through the superradiance *** compare these new effects on the binary with the well-studied effects from dynamical friction with dark matter and dipole radiation in model-independent ***,we discuss the constraints from LIGO/Virgo and study the detectability of the ultralight axion particles at LISA and TianQin.

关键词： gravitational wave axion dark matter

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Population I Cepheids and understanding star formation history of the Small Magellanic Cloud

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research in Astronomy and Astrophysics 2016年第4期16卷 71-78页

作者： Yogesh Chandra Joshi Auro Prasad Mohanty Santosh Joshi Aryabhatta research Institute of observational Sciences Manora PeakNainital 263002India National Institute of Technology Rourkela 769008India

In this paper, we study the age and spatial distributions of Cepheids in the Small Magellanic Cloud （SMC） as a function of their ages using data from the OGLE III photometric catalogue. A period - age relation derived for Classical Cepheids in the Large Magellanic Cloud （LMC） has been used to find the ages of Cepheids. The age distribution of the SMC Classical Cepheids is found to have a peak at log（Age）： 8.40 ± 0.10 which suggests that a major star formation event might have occurred in the SMC about 250 4- 50 Myr ago. It is believed that this star forming burst had been triggered by close interactions of the SMC with the LMC and/or the Milky Way. A comparison of the observed spatial distributions of the Cepheids and open star clusters has also been carried out to study the star formation scenario in the SMC.

关键词： stars: Cepheids -- star type: Pop I (classical) -- galaxies: SMC -- methods: statistical

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Projecting Spring Consecutive Rainfall Events in the Three Gorges Reservoir Based on Triple-Nested Dynamical Downscaling

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Advances in Atmospheric Sciences 2024年第8期41卷 1539-1558页

作者： Yanxin ZHENG Shuanglin LI Noel KEENLYSIDE Shengping HE Lingling SUO Department of Atmospheric Science CMA-CUG Joint Centre for Severe Weather and Climate and Hydro-geological HazardsChina University of GeosciencesWuhan 430074China Institute of Atmospheric Physics and Climate Change research Center Chinese Academy of SciencesBeijing 100029China Three Gorges National Climatological Observatory Yichang 443099China Geophysical Institute University of Bergen and Bjerknes Centre for Climate ResearchBergen 5007Norway Nansen Environmental and Remote Sensing Center and Bjerknes Centre for Climate research Bergen 5007Norway Nansen-Zhu International research Centre Institute of Atmospheric PhysicsChinese Academy of SciencesBeijing 100029China

Spring consecutive rainfall events(CREs) are key triggers of geological hazards in the Three Gorges Reservoir area(TGR), China. However, previous projections of CREs based on the direct outputs of global climate models(GCMs) are subject to considerable uncertainties, largely caused by their coarse resolution. This study applies a triple-nested WRF(Weather research and Forecasting) model dynamical downscaling, driven by a GCM, MIROC6(Model for Interdisciplinary research on Climate, version 6), to improve the historical simulation and reduce the uncertainties in the future projection of CREs in the TGR. Results indicate that WRF has better performances in reproducing the observed rainfall in terms of the daily probability distribution, monthly evolution and duration of rainfall events, demonstrating the ability of WRF in simulating CREs. Thus, the triple-nested WRF is applied to project the future changes of CREs under the middle-of-the-road and fossil-fueled development scenarios. It is indicated that light and moderate rainfall and the duration of continuous rainfall spells will decrease in the TGR, leading to a decrease in the frequency of CREs. Meanwhile, the duration, rainfall amount, and intensity of CREs is projected to regional increase in the central-west TGR. These results are inconsistent with the raw projection of MIROC6. observational diagnosis implies that CREs are mainly contributed by the vertical moisture advection. Such a synoptic contribution is captured well by WRF, which is not the case in MIROC6,indicating larger uncertainties in the CREs projected by MIROC6.

关键词： triple-nested downscaling Three Gorges Reservoir area consecutive rainfall events geological hazards projection

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Long-term photometric study of a faint W UMa binary in the direction of M31

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research in Astronomy and Astrophysics 2017年第11期17卷 59-70页

作者： Yogesh Chandra Joshi Rukmini Jagirdar Aryabhatta research Institute of observational Sciences Manora Peak Nainital 263002 India Center for Advanced Study in Astronomy Osmania University 500007 India

We carry out a re-analysis of the photometric data in Rclc bands which were taken during the Nainital Microlensing Survey from 1998 to 2002 with the aim to detect gravitational microlensing events in the direction of M31. Here, we do photometric analysis of a faint W UMa binary CSS_JO04259.3＋410629 identified in the target field. The orbital period of this star is found to be 0.266402±0.000018 d. The photometric mass ratio, q, is found to be 0.28±0.01. The photometric light curves are investigated using the Wilson-Devinney （WD） code and absolute parameters are determined using empirical relations which provide masses and radii of the binary as M1 = 1.19±0.09M⊙, M2 = 0.33±0.02M⊙ and R1 = 1.02±0.04R⊙, R2 = 0.58±0.08Re respectively based on Rc band data. Quite similar values are found by analyzing/c band data. From the photometric light curve examination, the star is understood to be a low mass-ratio overcontact binary of A-subtype with a high fill-out factor of about 47%. The binary system is found to be located approximately at a distance of 2.64±0.03 kpc having a separation of 2.01 ±0.05 Re between the two components.

关键词： methods: observational -- techniques: photometric -- binaries: eclipsing -- stars: funda- mental parameters

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Photometric studies of two W UMa type variables in the field of distant open cluster NGC 6866

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research in Astronomy and Astrophysics 2016年第4期16卷 87-96页

作者： Yogesh Chandra Joshi Rukmini Jagirdar Santosh Joshi Aryabhatta research Institute of observational Sciences Manora PeakNainital 263002India Center for Advanced Study in Astronomy Osmania UniversityHyderabad 500007India

We present photometric analysis of the two W UMa type binaries identified in the field of distant open star cluster NGC 6866. Although these systems, namely ID487 and ID494, were reported by Joshi et al., a detailed study of these stars has not been carried out before. The orbital periods of these stars are found to be 0.415110±0.000001 day and 0.366709±0.000004 day, respectively. Based on the photometric and infrared colors, we find their respective spectral types to be K0 and K3. The photometric light vari- ations of both stars show the O＇Connell effect which can be explained by employing a dark spot on the secondary components. The V and I band light curves are analyzed using the Wilson-Devinney （WD） code and relations given by Gazeas which yield radii and masses for the binary components of star ID487 of R1 = 1.24 ± 0.01R,R2 = 1.11 4- 0.02Re, and M1 = 1.24 ± 0.02Me, M2 = 0.96 ±0.05Me and for star ID494 of R1 = 1.22 ± 0.02Re, R2 = 0.81 4- 0.01 Re, and M1 = 1.20 4- 0.06 Me, M2 = 0.47 4- 0.01 Me.

关键词： methods: observational -- techniques: photometric -- binaries: eclipsing -- stars: fundamen-tal parameters

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