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Acta Pharmaceutica Sinica B 2020年第10期10卷 1989-2001页

作者： Ludan Li Yu Jiang Yuanyuan Liu Zhitao niu Qingyun Xue Wei Liu Xiaoyu Ding College of Life Sciences Nanjing Normal UniversityNanjing 210023China

Having great medicinal values,Dendrobium species of"Fengdou"(DSFs)are a taxonomically complex group in Dendrobium genus including many closely related and recently diverged *** used DNA markers have been proved to be insufficient in authenticating many species of this ***,we investigated 101 complete plastomes from 23 DSFs,comprising 72 newly sequenced and 29 documented,which all exhibited well-conserved genomic organization and gene *** comparison showed the co-occurrence of single nucleotide polymorphisms(SNPs)and insertions/deletions(indels),which can be explained by both the repeat-associated and indel-associated mutation ***,guanine-cytosine(GC)content was found to be negatively correlated with the three divergence variables(SNPs,indels and repeats),indicating that GC content may reflect the level of the local sequence *** species authentication analyses revealed that the relaxed filtering strategies of sequence alignment had no negative impact on species *** assessing the maximum likelihood(ML)trees inferred from different datasets,we found that the complete plastome and large single-copy(LSC)datasets both successfully identified all 23 DSFs with the maximum bootstrap ***,owing to the high efficiency of LSC in species identification,we recommend using LSC for accurate authentication of DSFs.

关键词： Dendrobium species of"Fengdou" Authentication Large single-copy(LSC) Plastomic comparison

Historical development of karst evergreen broadleaved forests in East Asia has shaped the evolution of a hemiparasitic genus Brandisia(Orobanchaceae)

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Plant Diversity 2023年第5期45卷 501-512页

作者： Zhe Chen Zhuo Zhou Ze-Min Guo Truong Van Do Hang Sun Yang niu CAS Key Laboratory for Plant Diversity and Biogeography of East Asia Kunming Institute of BotanyChinese Academy of Sciences132 Lanhei RoadKunming 650201YunnanChina University of Chinese Academy of Sciences Beijing 100049China Vietnam National Museum of Nature Vietnam Academy of Science and Technology18 Hoang Quoc VietCau Giay 10000HanoiVietnam Graduate University of Science and Technology Vietnam Academy of Science and Technology18 Hoang Quoc VietCau Giay 10000HanoiVietnam

Brandisia is a shrubby genus of about eight species distributed basically in East Asian evergreen broadleaved forests(EBLFs),with distribution centers in the karst regions of Yunnan,Guizhou,and Guangxi in southwestern *** on the hemiparasitic and more or less liana habits of this genus,we hypothesized that its evolution and distribution were shaped by the development of EBLFs *** test our hypothesis,the most comprehensive phylogenies of Brandisia hitherto were constructed based on plastome and nuclear loci(nrDNA,PHYA and PHYB);then divergence time and ancestral areas were inferred using the combined nuclear loci *** analyses reconfirmed that Brandisia is a member of Orobanchaceae,with unstable placements caused by nuclear-plastid *** Brandisia,three major clades were well supported,corresponding to the three subgenera based on *** was inferred to have originated in the early Oligocene(32.69 Mya)in the Eastern Himalayas-SW China,followed by diversification in the early Miocene(19.45 Mya)in karst *** differentiation dates of Brandisia were consistent with the origin of keystone species of EBLFs in this region(e.g.,Fagaceae,Lauraceae,Theaceae,and Magnoliaceae)and the colonization of other characteristic groups(e.g.,Gesneriaceae and Mahonia).These findings indicate that the distribution and evolution of Brandisia were facilitated by the rise of the karst EBLFs in East *** addition,the woody and parasitic habits,and pollination characteristics of Brandisia may also be the important factors affecting its speciation and dispersal.

关键词： Biogeography Brandisia Evergreen broadleaved forests(EBLFs) Karst Orobanchaceae Phylogeny

Numerical simulation of liquid desiccant evaporator driven by heat pump

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Journal of Central South University 2019年第8期26卷 2197-2213页

作者： niu Run-ping CHEN Xiao-yi WANG Zi-ye KUANG Da-qing School of Environment and Energy Engineering Beijing University of Civil Engineering and Architecture

The standard k-ε turbulence model and discrete phase model (DPM) were used to simulate the heat and mass transfer in a liquid-desiccant evaporator driven by a heat pump using FLUENT software, and the temperature field and velocity field in the device were obtained. The performance of the liquid-desiccant evaporator was studied as the concentration of the inlet solution varied between 21% and 30% and the pipe wall temperature between 30 and 50 ℃. Results show that the humidification rate and the humidification efficiency increased with the inlet air temperature, the solution flow rate, the solution temperature, and the pipe wall temperature. The humidification rate and humidification efficiency decreased with increasing moisture content in inlet air and the concentration of inlet solution. The humidification rate increased substantially but the humidification efficiency decreased as the inlet air flow rate increased. The error between the simulations and experimental results is acceptable, meaning that our model can provide a theoretical basis for optimizing the performance of a humidifying evaporator.

关键词： heat pump condensation heat discrete phase model (DPM) liquid desiccant evaporator numerical simulation

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表面活性剂在MOFs材料制备中的应用

日用化学工业（中英文） 2024年第5期54卷 581-587页

作者：杨许召袁康康吴龙焕牛彩奇张盈盈李亚坤王军郑州轻工业大学材料与化学工程学院郑州市精细化学品重点实验室河南郑州450001

金属有机骨架材料(Metal-Organic Frameworks,MOFs)具有比表面积大、孔径可调、性能可控等突出优点,在气体存储、吸附与分离、催化反应、传感等领域中有广泛的应用前景。表面活性剂在MOFs材料制备中,可以控制晶体的尺寸、孔径和几何形状... 详细信息

金属有机骨架材料(Metal-Organic Frameworks,MOFs)具有比表面积大、孔径可调、性能可控等突出优点,在气体存储、吸附与分离、催化反应、传感等领域中有广泛的应用前景。表面活性剂在MOFs材料制备中,可以控制晶体的尺寸、孔径和几何形状,还可以限制纳米晶体的纵向生长,促进2D结构的形成,且制备出的MOFs材料结构稳定、不易坍塌。综述了常规表面活性剂和双子表面活性剂、离子液体表面活性剂等特种表面活性剂在MOFs材料制备中的应用,如用作模板剂、封端剂等。对表面活性剂在实现多级孔MOFs形貌和孔隙率的精确控制、特种表面活性剂及应用等进行了展望,为表面活性剂在MOFs材料制备中的应用指明了方向,也为MOFs材料的制备提供了更加丰富的路径。

关键词：金属有机骨架材料表面活性剂模板剂应用

Lactobacillus crispatus Modulates Vaginal Epithelial Cell Innate Response to Candida albicans

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Chinese Medical Journal 2017年第3期130卷 273-279页

作者： Xiao-Xi niu Ting Li Xu Zhang Su-Xia Wang Zhao-Hui Liu Department of Obstetrics and Gynecology Peking University First Hospital Beijing 100034 China Laboratory of Electron Microscopy Ultrastructural Pathology Center Peking University First Hospital Beijing 100034 China

Background： Vulvovaginal candidiasis is caused by Candida albicans. The vaginal epithelium, as the first site of the initial stage of infection by pathogens, plays an important role in resisting genital tract infections. Moreover, lactobacilli are predominant members of the vaginal microbiota that help to maintain a normal vaginal microenvironment. Therefore, Lactobacillus crispatus was explored for its capacity to intervene in the immune response of vaginal epithelial cells VK2/E6E7 to C. albicans. Methods： We examined the interleukin-2 （IL-2）, 4, 6, 8, and 17 produced by VK2/E6E7 cells infected with C. albicans and treated with L. crispatus in vitro. The capacity ofL. crispatus to adhere to VK2/E6E7 and inhibit C. albicans growth was also tested by scanning electron microscopy （SEM） and adhesion experiments. Results： Compared with group VK2/E6E7 with C. albicans, when treated with L. crispatus, the adhesion of C. albicans to VK2/E6E7 cells decreased significantly by 52.87 ± 1.22%, 47.03 ± 1.35%, and 42.20 ± 1.55% under competition, exclusion, and displacement conditions, respectively. SEM revealed that the invasion of C. albicans into VK2/E6E7 cells was caused by induced endocytosis and active penetration. L. crispatus could effectively protect the cells from the virulence ofhyphae and spores of C. albicans and enhance the local immune function of the VK2/E6E7 cells. The concentrations of IL-2, 6, and 17 were upregulated significantly （P 〈 0.0 1） and that of IL-8 were downregulated significantly （P 〈 0.0 1） in infected VK2/E6E7 cells treated with L. crispatus. The concentration of IL-4 was similar to that of the group VK2/ E6E7 with C. albicans （24.10 ± 0.97 vs. 23.12 ±0.76 pg/ml, P= 0.221）. Conclusions： L. crispatus can attenuate the virulence of C. albicans, modulate the secretion of cytokines and chemokines, and enhance the immune response of VK2/E6E7 cells in vitro. The vaginal mucosa has a potential function in the local immune responses against pathogens tha

关键词： Candida albicans Cytokines Immunity Lactobacillus crispatus Scanning Electron Microscope Vaginal Epithelial Cells

Electro-oxidation of Ni(Ⅱ)-citrate complexes at BDD electrode and simultaneous recovery of metallic nickel by electrodeposition

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Journal of Environmental Sciences 2022年第6期34卷 103-113页

作者： Qiongfang Zhuo Xiaofeng Xu Shuibo Xie Xiuwen Ren Zhongying Chen Bo Yang Yanliang Li Junfeng niu School of Civil Engineering University of South ChinaHengyang 421001China School of Environment and Civil Engineering Dongguan University of TechnologyDongguan 523808China South China Institute of Environmental Sciences MEEGuangzhou 510655China College of Chemistry and Environmental Engineering Shenzhen UniversityShenzhen 518071China

The simultaneous electro-oxidation of Ni(Ⅱ)-citrate and electrodeposition recovery of nickel metal were attempted in a combined electro-oxidation-electrodeposition reactor with a boron-doped diamond(BDD)anode and a polished titanium *** of initial nickel citrate concentration,current density,initial p H,electrode spacing,electrolyte type,and initial electrolyte dosage on electrochemical performance were *** efficiencies of Ni(Ⅱ)-citrate removal and nickel metal recovery were determined to be 100%and over 72%,respectively,under the optimized conditions(10 m A/cm^(2),pH 4.09,80 mmol/L Na_(2)SO_(4),initial Ni(Ⅱ)-citrate concentration of 75 mg/L,electrode spacing of 1 cm,and 180 min of electrolysis).Energy consumption increased with increased current density,and the energy consumption was 0.032 kWh/L at a current density of 10 m A/cm^(2)(pH 6.58).The deposits at the cathode were characterized by scanning electron microscopy(SEM),energy-dispersive spectrometry(EDS),X-ray diffraction(XRD),and X-ray photoelectron spectroscopy(XPS).These characterization results indicated that the purity of metallic nickel in cathodic deposition was over 95%.The electrochemical system exhibited a prospective approach to oxidize metal complexes and recover metallic nickel.

关键词： Electrochemical oxidation Electrodeposition BDD anode Metal complexes Metallic nickel recovery

Crustal structure and variation along the southern part of the Kyushu-Palau Ridge

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Acta Oceanologica Sinica 2022年第1期41卷 50-57页

作者： Xiaodong Wei Weiwei Ding Aiguo Ruan Jie Zhang Xiongwei niu Jiabiao Li Yong Tang Key Laboratory of Submarine Geosciences Ministry of Natural Resources/Second Institute of OceanographyMinistry of Natural ResourcesHangzhou 310012China Southern Marine Science and Engineering Guangdong Laboratory(Zhuhai) Zhuhai 519080China School of Oceanography Shanghai Jiao Tong UniversityShanghai 200240China

As an interoceanic arc,the Kyushu-Palau Ridge(KPR)is an exceptional place to study the subduction process and related magmatism through its interior velocity ***,the crustal structure and its nature of the KPR,especially the southern part with limited seismic data,are still in *** order to unveil the crustal structure of the southern part of the KPR,this study uses deep reflection/refraction seismic data recorded by 24 ocean bottom seismometers to reconstruct a detailed P-wave velocity model along the *** show strong alongridge variations either on the crustal velocity or the thickness of the KPR.P-wave velocity model is featured with(1)a crustal thickness between 6–12 km,with velocity increases from 4.0 km/s to 7.0 km/s from top to bottom;(2)high gradient(~1 s^(-1))in the upper crust but low one(<0.2 s^(-1))in the lower crust;(3)a slow mantle velocity between 7.2 km/s and 7.6 km/s in the uppermost mantle;and(4)inhomogenous velocity anomalies in the lower crust beneath *** comparing with the mature arc in the Izu-Bonin-Mariana arc in the east,this study suggests the southern part of KPR is a thicken oceanic crust rather than a typical arc *** origin of low velocities in the lower crust and upper mantle may be related with crustal differentiation,which implies advanced crustal evolution from normal oceanic crust to partly thicken oceanic *** velocities in the lower crust are related to the difference in magmatism.

关键词： P-wave velocity structure ocean bottom seismometer Kyushu-Palau Ridge magmatism thicken oceanic crust

Experimental and numerical analysis of secondary disasters induced by oxygen rich combustion within a tunnel

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Mining Science and Technology 2011年第6期21卷 897-901页

作者： Cheng Caixia Sun Fuchun Zhou Xinquan niu Huiyong Liang De State Key Laboratory of Intelligent Technology and Systems Tsinghua University Beijing 100084 China State Key Laboratory of Coal Resources and Mine Safety China University of Mining ＆ Technology Beijing 100083 China School of Energy and Safety Engineering Hunan University of Science and Technology Xiangtan 411201 China

Various physical parameters, including gas concentrations (O2, CO, CH4, and H2) and temperatures at dif- ferent air velocities, were determined for full scale wood fires in the Chongqing Coal Research Institute fire test tunnel. Both experimental measurements and numerical simulations are discussed. The numer- ical analysis was performed with the computational fluid dynamics software package ''FLUENT''. The results show that the experimental data agree with the simulation results. The results verify that Roberts' theory of burning is correct. They also prove that the air velocity is the key factor that determines the type of combustion. Also, it is shown that secondary disasters are unlikely for oxygen rich combustion with a limited fire load.

关键词： Numerical analysis Combustion type Oxygen-enriched combustion Secondary disasters

Curricular Robust Reinforcement Learning via GAN-Based Perturbation Through Continuously Scheduled Task Sequence

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Tsinghua Science and Technology 2023年第1期28卷 27-38页

作者： Yike Li Yunzhe Tian Endong Tong Wenjia niu Yingxiao Xiang Tong Chen Yalun Wu Jiqiang Liu Beijing Key Laboratory of Security and Privacy in Intelligent Transportation Beijing Jiaotong UniversityBeijing 100044China

Reinforcement learning(RL),one of three branches of machine learning,aims for autonomous learning and is now greatly driving the artificial intelligence development,especially in autonomous distributed systems,such as cooperative Boston Dynamics ***,robust RL has been a challenging problem of reliable aspects due to the gap between laboratory simulation and real *** efforts have been made to approach this problem,such as performing random environmental perturbations in the learning ***,one cannot guarantee to train with a positive perturbation as bad ones might bring failures to *** this work,we treat robust RL as a multi-task RL problem,and propose a curricular robust RL *** first present a generative adversarial network(GAN)based task generation model to iteratively output new tasks at the appropriate level of difficulty for the current ***,with these progressive tasks,we can realize curricular learning and finally obtain a robust *** experiments in multiple environments demonstrate that our method improves the training stability and is robust to differences in training/test conditions.

关键词： robust reinforcement learning generative adversarial network(GAN)based model curricular learning

A re-assessment of nickel-doping method in iron isotope analysis on rock samples using multi-collector inductively coupled plasma mass spectrometry

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Acta Geochimica 2020年第3期39卷 355-364页

作者： Hongmei Gong Pengyuan Guo Shuo Chen Meng Duan Pu Sun Xiaohong Wang Yaoling niu Key Laboratory of Marine Geology and Environment Institute of OceanologyChinese Academy of SciencesQingdao 266071China Qingdao National Laboratory for Marine Science and Technology Qingdao 266061China Department of Earth Sciences Durham UniversityDurham DH13LEUK School of Earth Science and Resources China University of GeosciencesBeijing 100083China Institute of Oceanology Chinese Academy of SciencesNanhai Road 7Qingdao 266071ShandongChina

Element doping has been proved to be a useful method to correct for the mass bias fractionation when analyzing iron isotope *** present a systematic re-assessment on how the doped nickel may affect the iron isotope analysis in this study by carrying out several *** find three important factors that can affect the analytical results,including the Ni:Fe ratio in the analyte solutions,the match of the Ni:Fe ratio between the unknown sample and standard solutions,and the match of the Fe concentration between the sample and standard ***,caution is required when adding Ni to the analyte Fe solutions before *** our method,theδ56Fe and δ57Fe values of the USGS standards W-2 a,BHVO-2,BCR-2,AGV-2 and GSP-2 are consistent with the recommended literature values,and the long-term(one year) external reproducibility is better than 0.03 and 0.05‰(2 SD) for δ56Fe and δ57Fe,***,the analytical method established in our laboratory is a method of choice for high quantity Fe isotope data in geological materials.

关键词： Fe isotope Ni-doping Stable isotope Precision and accuracy Mass bias correction Pseudohigh mass resolution