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On the Identification of N-rich Metal-poor Field Stars with Future Chinese Space Station Telescope

Research in Astronomy and Astrophysics 2024年第1期24卷 151-164页

作者： Jiajun Zhang Baitian Tang Jiang Chang Xiangxiang Xue JoséGFernández-Trincado chengyuan Li Long Wang Hao Tian Yang huang School of Physics and Astronomy Sun Yat-sen UniversityZhuhai 519082China CSST Science Center for the Guangdong-Hong Kong-Macao Greater Bay Area Sun Yat-sen UniversityZhuhai 519082China Purple Mountain Observatory Chinese Academy of SciencesNanjing 210034China Key Lab of Optical Astronomy National Astronomical ObservatoriesChinese Academy of SciencesBeijing 100101China Instituto de Astronomía Universidad Católica del NorteAv.Angamos 0610AntofagastaChile Key Lab of Space Astronomy and Technology National Astronomical ObservatoriesChinese Academy of SciencesBeijing 100101China School of Astronomy and Space Science University of Chinese Academy of SciencesBeijing 100049China

During the long term evolution of globular clusters(GCs), some member stars are lost to the field. The recently found nitrogen-rich(N-rich) metal-poor field stars are promising candidates of these GC escapees, since N enhancement is the fingerprint of chemically enhanced populations in GCs. In this work, we discuss the possibility of identifying N-rich metal-poor field stars with the upcoming Chinese Space Station Telescope(CSST). We focus on the main survey camera with NUV, u, g, r, i, z, y filters and slitless spectrograph with a resolution about 200.The combination of UV sensitive equipment and prominent N-related molecular lines in the UV band bodes well for the identification: the color–color diagram of(u-g) versus(g-r) is capable of separating N-rich field stars from normal halo stars, if metallicity can be estimated without using the information on u-band photometry.Besides, the synthetic spectra show that a signal-to-noise ratio of 10 is sufficient to identify N-rich field stars. In the near future, a large sample of N-rich field stars found by CSST, combined with state-of-the-art N-body simulations will be crucial to deciphering GC-Galaxy co-evolution.

关键词： stars:chemically peculiar stars:abundances techniques:photometric techniques:spectroscopic

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Plume:Lightweight and Generalized Congestion Control with Deep Reinforcement Learning

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China Communications 2022年第12期19卷 101-117页

作者： Dehui Wei Jiao Zhang Xuan Zhang chengyuan huang State Key Laboratory of Networking and Switching Technology BUPT 100876China

Congestion control(CC)is always an important issue in the field of networking,and the enthusiasm for its research has never diminished in both academia and industry.In current years,due to the rapid development of machine learning(ML),the combination of reinforcement learning(RL)and CC has a striking effect.However,These complicated schemes lack generalization and are too heavyweight in storage and computing to be directly implemented in mobile devices.In order to address these problems,we propose Plume,a high-performance,lightweight and generalized RL-CC scheme.Plume proposes a lightweight framework to reduce the overheads while preserving the original performance.Besides,Plume innovatively modifies the framework parameters of the reward function during the retraining process,so that the algorithm can be applied to a variety of scenarios.Evaluation results show that Plume can retain almost all the performance of the original model but the size and decision latency can be reduced by more than 50%and 20%,respectively.Moreover,Plume has better performances in some special scenes.

关键词： congestion control deep reinforcement learning lightweight generalization

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Driving factors behind multiple populations

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Science China(Physics,Mechanics & Astronomy) 2024年第5期67卷 172-181页

作者： Ruoyun huang Baitian Tang chengyuan Li Doug Geisler Mario Mateo Ying-Yi Song Holger Baumgardt Julio A.Carballo-Bello Yue Wang Jundan Nie Bruno Dias JoséG.Fernández-Trincado School of Physics and Astronomy Sun Yat-sen UniversityZhuhai 519082China CSST Science Center for the Guangdong-Hong Kong-Macao Greater Bay Area Zhuhai 519082China Departamento de Astronomía Universidad de ConcepcionConcepcionChile Instituto de Investigación Multidisciplinario en Ciencia y Tecnología Universidad de La SerenaLa SerenaChile Departamento de Astronomía Facultad de CienciasUniversidad de La SerenaChile Department of Astronomy University of MichiganAnn Arbor 48109USA David A.Dunlap Department of Astronomy&Astrophysics University of TorontoToronto ON M5S 3H4Canada Dunlap Institute for Astronomy&Astrophysics University of TorontoToronto ON M5S 3H4Canada School of Mathematics and Physics The University of QueenslandSt.Lucia QLD 4072Australia Instituto de Alta Investigación Universidad de TarapacáAricaChile CAS Key Laboratory of Optical Astronomy National Astronomical ObservatoriesChinese Academy of SciencesBeijing 100101China Instituto de Astrofísica Departamento de Ciencias FísicasFacultad de Ciencias ExactasUniversidad Andres BelloSantiagoChile Instituto de Astronomía Universidad Católica del NorteAntofagastaChile

Star clusters were historically considered simple stellar populations,with all stars sharing the same age and initial chemical composition.However,the presence of chemical anomalies in globular clusters(GCs),called multiple stellar populations(MPs),has challenged star formation theories in dense environments.Literature studies show that mass,metallicity,and age are likely controlling parameters for the manifestation of MPs.Identifying the limit between clusters with/without MPs in physical parameter space is crucial to reveal the driving mechanism behind their presence.In this study,we look for MP signals in Whiting 1,which is traditionally considered a young GC.Using the Magellan telescope,we obtained low-resolution spectra withinλλ=3850-5500?for eight giants of Whiting 1.We measured the C and N abundances from the CN and CH spectral indices.C and N abundances have variations comparable with their measurement errors(~0.1 dex),suggesting that MPs are absent from Whiting 1.Combining these findings with literature studies,we propose a limit in the metallicity vs.cluster compactness index parameter space,which relatively clearly separates star clusters with/without MPs(GCs/open clusters).This limit is physically motivated.On a larger scale,the galactic environment determines cluster compactness and metallicity,leading to metal-rich,diffuse,old clusters formed ex situ.Our proposed limit also impacts our understanding of the formation of the Sagittarius dwarf galaxy:star clusters formed after the first starburst(age≤8-10 Gyr).These clusters are simple stellar populations because the enriched galactic environment is no longer suitable for MP formation.

关键词： stellar galactic galaxy

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Providing Guaranteed Network Performance across Tenants:Advances,Challenges and Opportunities

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China Communications 2021年第2期18卷 152-174页

作者： chengyuan huang Jiao Zhang Tao huang Yunjie Liu State Key Laboratory of Networking and Switching Technology BUPTBeijingChina Purple Mountain Laboratories NanjingChina

The varied network performance in the cloud hurts application performance.This increases the tenant’s cost and becomes the key hindrance to cloud adoption.It is because virtual machines(VMs)belonging to one tenant can reside in multiple physical servers and communication interference across tenants occasionally occurs when encountering network congestion.In order to prevent such unpredictability,it is critical for cloud providers to offer the guaranteed network performance at tenant level.Such a critical issue has drawn increasing attention in both academia and industry.Many elaborate mechanisms are proposed to provide guaranteed network performance,such as guaranteed bandwidth or bounded message delay across tenants.However,due to the intrinsic complexities and limited capabilities of commodity hardware,the deployment of these mechanisms still faces great challenges in current cloud datacenters.Moreover,with the rapid development of new technologies,there are new opportunities to improve the performance of existing works,but these possibilities are not under full discussion yet.Therefore,in this paper,we survey the latest development of the network performance guarantee approaches and summarize them based on their features.Then,we explore and discuss the possibilities of using emerging technologies as knobs to upgrade the performance or overcome the inherent shortcomings of existing advances.We hope this article will help readers quickly Received:Apr.07,2020 Revised:Oct.23,2020 Editor:Haifeng Zheng understand the causes of the problems and serve as a guide to motivate researchers to develop innovative algorithms and frameworks.

关键词： cloud computing network performance guaranteed bandwidth guaranteed delay

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水平渗滤系统的污染物去除效果及动力学分析

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环境工程学报 2024年第2期18卷 430-440页

作者：廖俭霞黄智高澍宿程远广西师范大学环境与资源学院桂林541006 珍稀濒危动植物生态与环境保护教育部重点实验室(广西师范大学) 桂林541006

基于人工快渗(CRIS)和水平潜流人工湿地(HSSFCWs)构建了水平流人工渗滤系统(HFCIS),研究了该系统对耗氧有机物(以COD计)、氨氮(NH4+-N)的沿程去除情况和污染物在系统内的垂向分布情况,并进行了动力学分析。结果表明,在水力负荷为0.083 m... 详细信息

基于人工快渗(CRIS)和水平潜流人工湿地(HSSFCWs)构建了水平流人工渗滤系统(HFCIS),研究了该系统对耗氧有机物(以COD计)、氨氮(NH4+-N)的沿程去除情况和污染物在系统内的垂向分布情况,并进行了动力学分析。结果表明,在水力负荷为0.083 m·d^(-1)、进水耗氧有机物(以COD计)浓度为220~630 mg·L^(-1)、NH_(4)^(+)-N质量浓度为13~47 mg·L^(-1)时,COD、NH_(4)^(+)-N的去除率分别为88.6%和91.9%以上。在水力负荷为0.25 m·d^(-1)的条件下,进水耗氧有机物(以COD计)和NH_(4)^(+)-N质量浓度分别为613~690mg·L^(-1)和36~48mg·L^(-1)时,总去除率分别为95.5%和78.2%以上。水平方向沿程污染物质量浓度呈现逐渐衰减的趋势,污染物降解符合一阶动力学模型,去除速率常数在CRIS和HSSFCWs的速率常数范围内并处于较高水平。该HFCI系统填料简单,复氧效果好,污染物去除性能优异,提高了土地利用率,建造位置选择较为灵活,在分散式污水处理中有独特的优势。

关键词：水平渗滤系统动力学去除速率常数分散式污水处理

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新标09CrCuSb耐酸钢的耐50%H_(2)SO_(4)腐蚀性能

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腐蚀与防护 2024年第4期45卷 8-13页

作者：郑健张佳伟袁渊张成元黄峰刘静湖南华菱湘潭钢铁有限公司湘潭411101 武汉科技大学省部共建耐火材料与冶金国家重点实验室武汉430081

通过电化学测试和全浸腐蚀试验,研究了不同温度(25,50,60,70℃)条件下新标09CrCuSb耐酸钢在50%H_(2)SO_(4)溶液中的腐蚀行为。结果表明:随着温度从25℃升至70℃,新标09CrCuSb钢的腐蚀速率整体呈现增大趋势,在70℃时,腐蚀速率达到最高,为... 详细信息

通过电化学测试和全浸腐蚀试验,研究了不同温度(25,50,60,70℃)条件下新标09CrCuSb耐酸钢在50%H_(2)SO_(4)溶液中的腐蚀行为。结果表明:随着温度从25℃升至70℃,新标09CrCuSb钢的腐蚀速率整体呈现增大趋势,在70℃时,腐蚀速率达到最高,为2.70 g/(m^(2)·h),这与随温度升高,腐蚀产物中具有保护性作用的Fe_(3)O_(4)含量减少,无保护作用的FeSO_(4)·H_(2)O含量增加以及锈层中微孔变化有关。另外,由于新标调整了09CrCuSb钢中Cu、Mo、Sn、Sb、W等元素的含量,与旧标09CrCuSb钢相比,阳极维钝电流密度J维钝降低,同等温度条件下,新标09CrCuSb钢的耐蚀性得到较大改善。

关键词：新标09CrCuSb耐酸钢 50%H_(2)SO_(4)溶液腐蚀温度影响

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Carbon dots derived from Poria cocos polysaccharide as an effective“on-off”fluorescence sensor for chromium(Ⅵ)detection

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Journal of Pharmaceutical Analysis 2022年第1期12卷 104-112页

作者： Qianqian huang Qianqian Bao chengyuan Wu Mengru Hu Yunna Chen Lei Wang Weidong Chen Anhui Province Key Laboratory of Chinese Medicinal Formula Anhui University of Chinese MedicineHefei230012China

Chromium is a harmful contaminant showing mutagenicity and carcinogenicity.Therefore,detection of chromium requires the development of low-cost and high-sensitivity sensors.Herein,blue-fluorescent carbon quantum dots were synthesized by one-step hydrothermal method from alkali-soluble Poria cocos polysaccharide,which is green source,cheap and easy to obtain,and has no pharmacological activity due to low water solubility.These carbon quantum dots exhibit good fluorescence stability,water solubility,anti-interference and low cytotoxicity,and can be specifically combined with the detection of Cr(Ⅵ)to form a non-fluorescent complex that causes fluorescence quenching,so they can be used as a label-free nanosensor.High-sensitivity detection of Cr(Ⅵ)was achieved through internal filtering and static quenching effects.The fluorescence quenching degree of carbon dots fluorescent probe showed a good linear relationship with Cr(Ⅵ)concentration in the range of 1-100μM.The linear equation was F;/F=0.9942+0.01472[Cr(Ⅵ)](R;=0.9922),and the detection limit can be as low as 0.25μM(S/N=3),which has been successfully applied to Cr(Ⅵ)detection in actual water samples herein.

关键词： Carbon dots Alkali-soluble Poria cocos polysaccharide Cr(Ⅵ)detection Internal filtering effect Static quenching effect

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PLX8394,a RAF inhibitor,inhibits enterovirus 71 replication by blocking RAF/MEK/ERK signaling

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Virologica Sinica 2023年第2期38卷 276-284页

作者： chengyuan Wu Guangyan Zhu Fang Qiu Fuli Ren Binbin Lin Dingyu Zhang Qingyu Yang Chaolin huang Wuhan Jinyintan Hospital Tongji Medical College of Huazhong University of Science and TechnologyWuhan430023China State Key Laboratory of Virology Wuhan Institute of VirologyChinese Academy of SciencesWuhan430071China Division of Life Sciences and Medicine University of Science and Technology of ChinaHefei230027China

Enterovirus 71(EV71)poses a serious threat to human health,with scattered outbreaks worldwide.There are several vaccines against a few EV71 strains but no efficient drug for the treatment of EV71 infection.Therefore,it is urgent and of significance to develop anti-EV71 drugs.Here,we found that PLX8394,a RAF inhibitor,possesses high antiviral activity against EV71 in vitro,being superior to the traditional clinical drug ribavirin.Moreover,PLX8394 exhibits broad-spectrum antiviral activity against enteroviruses.Notably,in a suckling mouse model,PLX8394 provided a 70%protection rate for EV71-infected mice,reduced the viral load in liver and heart tissues,and relieved the inflammatory response.A mechanistic study showed that PLX8394 inhibited EV71 by suppressing the RAF/MEK/ERK signaling pathway.Thus,PLX8394 lays a foundation for the development of new drugs against EV71.

关键词： Enterovirus 71(EV71) RAF inhibitor Hand,foot,and mouth disease(HFMD) RAF/MEK/ERK signaling Pathway Antiviral agents

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瘤胃上皮短链脂肪酸转运蛋白研究进展

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中国畜牧杂志 2024年第6期60卷 54-59页

作者：自玉杰和风段承远李承环李浩楠李哲黄长征冷静云南农业大学云南省动物营养与饲料重点实验室云南昆明650201 云南农业大学动物科学技术学院云南昆明650201 怒江州畜牧技术推广站云南怒江673100 怒江州泸水市老窝镇农业农村服务中心云南怒江673100

瘤胃是反刍动物消化粗饲料的重要器官,短链脂肪酸(SCFAs)作为瘤胃微生物的发酵产物可给动物机体提供能量,瘤胃上皮对SCFAs的吸收转运在瘤胃的健康发育中发挥着重要作用。本文对单羧酸转运蛋白(MCT)、阴离子交换蛋白(AE)、钠氢交换蛋白(N... 详细信息

瘤胃是反刍动物消化粗饲料的重要器官,短链脂肪酸(SCFAs)作为瘤胃微生物的发酵产物可给动物机体提供能量,瘤胃上皮对SCFAs的吸收转运在瘤胃的健康发育中发挥着重要作用。本文对单羧酸转运蛋白(MCT)、阴离子交换蛋白(AE)、钠氢交换蛋白(NHE)、腺瘤下调蛋白(DRA)和假定离子转运蛋白(PAT)5种主要瘤胃上皮SCFAs转运蛋白进行综述,以期为研究反刍动物营养调控和瘤胃健康发育提供理论依据。

关键词：瘤胃上皮短链脂肪酸短链脂肪酸转运蛋白

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Innovative method of culturing bdelloid rotifers for the application of wastewater biological treatment

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Frontiers of Environmental Science & Engineering 2022年第4期16卷 37-45页

作者： Yun He Jianyong Liu chengyuan Shen Xuewen Yi Xiaowei Li Xin huang Kokyo Oh Cuoji Ding School of Environmental and Chemical Engineering Shanghai UniversityShanghai 200444China Shanghai Environmental School Shanghai 200135China Shanghai Jinshan Municipal Bureau of Ecology and Environment Shanghai 200540China Center for Environmental Science in Saitama Saitama 347-0115Japan

This study aims to establish a simple and efficient method for the mass culture of bdelloid rotifers,which is the basis for the application of bdelloid rotifers as biological manipulators to improve wastewater biological treatment performance.A common bdelloid rotifer,Habrotrocha sp.,in a wastewater biological treatment system was selected as the culture target.Rotifers fed on flour could reproduce faster than those fed traditional food such as Chlorella vulgaris or mixed bacteria.As a rotifer food,flour has the advantages of simple preparation,effortless preservation,and low cost compared to live Chlorella vulgaris or mixed bacteria,so it is more suitable for the mass culture of rotifers.The optimal rotifer culture conditions using flour as food were also studied.According to the experimental results,the recommended rotifer culture conditions arc a flour particle size of 1 a flour concentration of 6×10^(6) cell/mL,a temperature of 28℃,a pH level of 6.5 and salinity of 100-500 mg/L.In addition,the sludge volume index in the sequencing batch reactor(SBR)with the addition of cultured rotifers was 59.9 mL/g at the end of operation and decreased by 18.2%compared to SBR without rotifer,which indicates that the cultured rotifers still retained the ftinction of helping to improve sludge settling.This function may be related to the rotifer's role in inhibiting bacteria from producing loosely bound extracellular polymeric substances in the SBR.

关键词： Mass culture Bdelloid rotifer Habrotrocha Wheat flour Sludge settleability

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