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62篇 您的检索式:作者名="Han Yifan"
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1Single-cell transcriptomic analysis defines the interplay between tumor cells,viral infection,and the microenvironment in nasopharyngeal carcinoma显示文摘Nasopharyngeal carcinoma(NPC)is an Epstein-Barr virus(EBV)-associated malignancy with a complex tumor ecosystem.How the interplay between tumor cells,EBV,and the microenvironment contributes to NPC progression and immune evasion remains unclear.Here we performed single-cell RNA sequencing on^104,000 cells from 19 EBV^+NPCs and 7 nonmalignant nasopharyngeal biopsies,simultaneously profiling the transcriptomes of malignant cells,EBV,stromal and immune cells.Overall,we identified global upregulation of interferon responses in the multicellular ecosystem of NPC.Notably,an epithelial–immune dual feature of malignant cells was discovered and associated with poor prognosis.Functional experiments revealed that tumor cells with this dual feature exhibited a higher capacity for tumorigenesis.Further characterization of the cellular components of the tumor microenvironment(TME)and their interactions with tumor cells revealed that the dual feature of tumor cells was positively correlated with the expression of co-inhibitory receptors on CD8^+tumor-infiltrating T cells.In addition,tumor cells with the dual feature were found to repress IFN-γproduction by T cells,demonstrating their capacity for immune suppression.Our results provide new insights into the multicellular ecosystem of NPC and offer important clinical implications.Shanzhao Jin Ruoyan Li Ming-Yuan Chen Chao Yu Lin-Quan Tang Yan-Min Liu Jiang-Ping Li Yi-Na Liu Yi-Ling Luo Yifan Zhao Yu Zhang Tian-Liang Xia Shang-Xin Liu Qi Liu Guan-Nan Wang Rui You Jing-Yun Peng Jiang Li Feng Han Jianwei Wang Qiu-Yan Chen Li Zhang Hai-Qiang Mai Benjamin E.Gewurz Bo Zhao Lawrence S.Young Qian Zhong Fan Bai Mu-Sheng Zeng 2020Cell Research2020,30,11:16
2Interferon-armed RBD dimer enhances the immunogenicity of RBD for sterilizing immunity against SARS-CoV-2显示文摘Severe acute respiratory syndrome coronavirus 2(SARS-CoV-2)has caused a global crisis,urgently necessitating the development of safe,efficacious,convenient-to-store,and low-cost vaccine options.A major challenge is that the receptor-binding domain(RBD)-only vaccine fails to trigger long-lasting protective immunity if used alone for vaccination.Shiyu Sun Yueqi Cai Tian-Zhang Song Yang Pu Lin Cheng Hairong Xu Jing Sun Chaoyang Meng Yifan Lin Haibin Huang Fang Zhao Silin Zhang Yu Gao Jian-Bao Han Xiao-Li Feng Dan-Dan Yu Yalan Zhu Pu Gao Haidong Tang Jincun Zhao Zheng Zhang Jiaming Yang Zhenxiang Hu Yang-Xin Fu Yong-Tang Zheng Hua Peng 2021Cell Research2021,31,9:7
3Ofloxacin loaded M0S2 nanoflakes for synergistic mild-temperature photothermal/antibiotic therapy with reduced drug resistance of bacteria显示文摘Antibiotic resistance is an increasingly serious threat to global public health, which can lead to the decrease of the effectiveness ofantibiotics. The combination therapy of antibiotic and mild temperature photothermal therapy (PTT) is adopted to address this issue inthis work. An antibiotic-loaded nanoplatform is fabricated based on two-dimensional (2D) molybdenum disulfide (M0S2) nanoflakesas effective near-infrared (NIR) photothermal agent. The M0S2 nanoflakes is modified with positively charged quaternized chitosan(QCS) to improve the dispersion stability and enhance the interaction between M0S2 nanoflakes and bacterial membrane. TheQCS modified M0S2 nanoflakes (QCS-M0S2) is expected to adhere onto the membrane of methicillin-resistant Staphylococcusaureus (MRSA) and depolarize the bacterial membrane by local hyperthermia under NIR irradiation. A first-line antibiotic, ofloxacin(OFLX), can be loaded onto QCS-M0S2 by π-π stacking and hydrophobic interaction. Due to the combined antibiotic-photothermaltherapy, superior bactericidal ability was achieved at mild temperature (45℃) and low antibiotic concentration. Such synergisticmild-temperature photothermal/antibiotic therapy can not only avoid the damage to neighboring tissue by PTT, but also reduce thedevelopment of drug resistance, providing an innovative way for the treatment of bacterial infections.Yue Huang Qiang Gao Xu Li Yifan Gao Haijie Han Qiao Jin Ke Yao Jian Ji 2020Nano Research2020,13,9:7
4The heterogeneity of islet autoantibodies and the progression of islet failure in type 1 diabetic patients显示文摘Type 1 diabetes mellitus is heterogeneous in many facets. The patients suffered from type 1 diabetes present several levels of islet function as well as variable number and type of islet-specific autoantibodies. This study was to investigate prevalence and heterogeneity of the islet autoantibodies and clinical phenotypes of type 1 diabetes mellitus; and also discussed the process of islet failure and its risk factors in Chinese type 1 diabetic patients. A total of 1,291 type 1 diabetic patients were enrolled in this study. Demographic information was collected. Laboratory tests including mixed-meal tolerance test, human leukocyte antigen alleles, hemoglobin A1 c, lipids, thyroid function and islet autoantibodies were conducted. The frequency of islet-specific autoantibody in newly diagnosed T1 DM patients(duration shorter than half year) was 73% in East China. According to binary logistic regressions, autoantibody positivity, longer duration and lower Body Mass Index were the risk factors of islet failure. As the disease developed, autoantibodies against glutamic acid decarboxylase declined as well as the other two autoantibodies against zinc transporter 8 and islet antigen 2. The decrease of autoantibodies was positively correlated with aggressive beta cell destruction. Autoantibodies can facilitate the identification of classic T1 DM from other subtypes and predict the progression of islet failure. As there were obvious heterogeneity in autoantibodies and clinical manifestation in different phenotypes of the disease, we should take more factors into consideration when identifying type 1 diabetes mellitus.Jin Liu Lingling Bian Li Ji Yang Chen Heng Chen Yong Gu Bingqin Ma Wei Gu Xinyu Xu Yun Shi Jian Wang Dalong Zhu Zilin Sun Jianhua Ma Hui Jin Xing Shi Heng Miao Bing Xin Yan Zhu Zhenwen Zhang Ruifang Bu Lan Xu Guangde Shi Wei Tang Wei Li Dongmei Zhou Jun Liang Xingbo Cheng Bimin Shi Jixiang Dong Ji Hu Chen Fang Shao Zhong Weinan Yu Weiping Lu Chenguang Wu Li Qian Jiancheng Yu Jialin Gao Xiaoqiang Fei Qingqing Zhang Xueqin Wang Shiwei Cui Jinluo Cheng Ning Xu Guofeng Wang Guoqing Han Chunrong Xu Yun Xie Minmin An Wei Zhang Zhixiao Wang Yun Cai Qi Fu Yu Fu Shuai Zheng Fan Yang Qingfang Hu Hao Dai Yu Jin Zheng Zhang Kuanfeng Xu Yifan Li Jie Shen Hongwen Zhou Wei He Xuqin Zheng Xiao Han Liping Yu Jinxiong She Mei Zhang Tao Yang 2016Science China(Life Sciences)2016,59,9:5
5Autologous fibroblasts induce fibrosis of the nucleus pulposus to maintain the stability of degenerative intervertebral discs显示文摘Lumbar degenerative disc diseases cause low back pain(LBP). The maintenance of the height and stability of the intervertebral disc(IVD) space is an effective treatment for LBP. The following study evaluated the effects of fibroblast injection on intervertebral disc degeneration(IDD) in a preclinical setting. Compared with the IDD group, the fibroblast treatment group demonstrated effective maintenance of IVD height, reduced endplate degeneration, and improved nuclear magnetic resonance signals and overall histological structure. In doing so, fibrotic IVDs maintained the stability and biomechanics of the vertebra. This finding is in agreement with clinical findings that human nucleus pulposus(NP) fibrosis is essential for the maintenance of IVD height and mechanical properties in patients following percutaneous endoscopic lumbar discectomy(PELD). Mechanistically, we demonstrated that injected fibroblasts not only proliferated but also induced NP cells to adopt a fibrotic phenotype via the secretion of TGF-β.Finally, to better mimic human conditions, the efficacy of autologous fibroblast injection in the treatment of IDD was further examined in a nonhuman primate cynomolgus monkey model due to their capacity for upright posture. We showed that the injection of fibroblasts could maintain the IVD height and rescue IVD signals in cynomolgus monkeys. Taken together, the results of our study reveal that autologous fibroblast injection can enhance the natural process of fibrosis during acute and subacute stages of stress-induced IDD. Fibrotic IVDs can maintain the stability, biological activity, and mechanical properties of the intervertebral space, thus providing a new direction for the treatment of intervertebral space-derived lumbar degenerative diseases.Chen Chen Tangjun Zhou Xiaojiang Sun Chen Han Kai Zhang Changqing Zhao Xunlin Li Haijun Tian Xiao Yang Yifan Zhou Zhiqian Chen An Qin Jie Zhao 2020Bone Research2020,8,1:3
6Interface-dominated mechanical behavior in advanced metal matrix composites显示文摘Metal matrix composites(MMCs)incorporate a reinforcing or functional secondary phase into a metal matrix to achieve specific properties.Of the parameters which may affect the mechanical behavior of MMCs,the structure and properties of the reinforcement/matrix interface play a crucial role.This article reviews recent developments in measuring the interfacial properties in advanced MMCs,with an emphasis on the use of micro-/nano-mechanical testing approaches.It is shown that,with the novel in situ and ex situ experimental capability,researchers can now obtain some of the critical interfacial properties as well as the effects of reinforcement/matrix interfaces on the composites’deformation and failure mechanisms that were unattainable previously by conventional methodologies.Moreover,the micro-/nano-mechanical testing platform allows for both fundamental and applied research on the composites’mechanical performance under service conditions,which is considered a promising and emerging research direction.Qiang Guo Yifan Han Di Zhang 2020Nano Materials Science2020,2,1:3
7Shifting from homogeneous to heterogeneous surfaces in estimating terrestrial evapotranspiration: Review and perspectives显示文摘Terrestrial evapotranspiration(ET)is a crucial link between Earth’s water cycle and the surface energy budget.Accurate measurement and estimation remain a major challenge in geophysical,biological,and environmental studies.Pioneering work,represented by Dalton and Penman,and the development of theories and experiments on turbulent exchange in the atmospheric boundary layer(ABL),laid the foundation for mainstream methodologies in ET estimation.Since the 1990s,eddy covariance(EC)systems and satellite remote sensing have been widely applied from cold to tropical and from arid to humid regions.They cover water surfaces,wetlands,forests,croplands,grasslands,barelands,and urban areas,offering an exceptional number of reports on diverse ET processes.Surface nocturnal ET,hysteresis between ET and environmental forces,turbulence intermittency,island effects on heterogeneous surfaces,and phase transition between underlying surfaces are examples of reported new phenomena,posing theoretical and practical challenges to mainstream ET methodologies.Additionally,based on non-conventional theories,new methods have emerged,such as maximum entropy production and nonparametric approaches.Furthermore,high-frequency on-site observation and aerospace remote sensing technology in combination form multi-scale observations across plant stomata,leaves,plants,canopies,landscapes,and basins.This promotes an insightful understanding of diverse ET processes and synthesizes the common mechanisms of the processes between and across spatial and temporal scales.All the recent achievements in conception,model,and technology serve as the basis for breaking through the known difficulties in ET estimation.We expect that they will provide a rigorous,reliable scientific basis and experimental support to address theoretical arguments of global significance,such as the water-heat-carbon cycle,and solve practical needs of national importance,including agricultural irrigation and food security,precise management of water resources and eco-environmental protection,and regulation of the urban thermal environment and climate change adaptation.Yuanbo LIU Guoyu QIU Hongsheng ZHANG Yonghui YANG Yinsheng ZHANG Quan WANG Wenzhi ZHAO Li JIA Xibin JI Yujiu XIONG Chunhua YAN Ning MA Shumin HAN Yifan CUI 2022Science China Earth Sciences2022,65,2:2
8Co-culture of Schwann cells and endothelial cells for synergistically regulating dorsal root ganglion behavior on chitosan-based anisotropic topology for peripheral nerve regeneration显示文摘Background:Anisotropic topologies are known to regulate cell-oriented growth and induce cell differentiation,which is conducive to accelerating nerve regeneration,while co-culture of endothelial cells(ECs)and Schwann cells(SCs)can significantly promote the axon growth of dorsal root ganglion(DRG).However,the synergistic regulation of EC and SC co-culture of DRG behavior on anisotropic topologies is still rarely reported.The study aims to investigate the effect of anisotropic topology co-cultured with Schwann cells and endothelial cells on dorsal root ganglion behavior for promoting peripheral nerve regeneration.Methods:Chitosan/artemisia sphaerocephala(CS/AS)scaffolds with anisotropic topology were first prepared using micro-molding technology,and then the surface was modified with dopamine to facilitate cell adhesion and growth.The physical and chemical properties of the scaffolds were characterized through morphology,wettability,surface roughness and component variation.SCs and ECs were co-cultured with DRG cells on anisotropic topology scaffolds to evaluate the axon growth behavior.Results:Dopamine-modified topological CS/AS scaffolds had good hydrophilicity and provided an appropriate environment for cell growth.Cellular immunofluorescence showed that in contrast to DRG growth alone,co-culture of SCs and ECs could not only promote the growth of DRG axons,but also offered a stronger guidance for orientation growth of neurons,which could effectively prevent axons from tangling and knotting,and thus may significantly inhibit neurofibroma formation.Moreover,the co-culture of SCs and ECs could promote the release of nerve growth factor and vascular endothelial growth factor,and up-regulate genes relevant to cell proliferation,myelination and skeletal development via the PI3K-Akt,MAPK and cytokine and receptor chemokine pathways.Conclusions:The co-culture of SCs and ECs significantly improved the growth behavior of DRG on anisotropic topological scaffolds,which may provide an important basis for the development of nerve grafts in peripheral nerve regeneration.Tiantian Zheng Linliang Wu Shaolan Sun Jiawei Xu Qi Han Yifan Liu Ronghua Wu Guicai Li 2022Burns & Trauma2022,10,1:2
9Association of human leukocyte antigen-DR-DQ-DP haplotypes with the risk of hepatitis B virus-related hepatocellular carcinoma显示文摘Aim:Genetic polymorphisms of human leukocyte antigen(HLA)class II molecules are associated with chronic hepatitis B virus(HBV)infection.We aimed to investigate the impacts of HLA-II haplotypes on viral evolution and the risks of HBV-caused liver diseases.Methods:HLA-DR-DQ-DP haplotypes were estimated in 1210 healthy controls,296 HBV clearance subjects,301 asymptomatic hepatitis B surface antigen carriers,770 chronic hepatitis B patients,443 HBV-related liver cirrhosis(LC)patients,and 1037 HBV-related hepatocellular carcinoma(HCC)patients.HBV mutations were determined by sequencing.The associations of HLA-DR-DQ-DP haplotypes with viral mutations and the risks of liver diseases were assessed by multivariate logistic regression.Results:Compared to HBV-free subjects,the haplotypes CCAACG,CCGACG,TCAATA,and TCGATA were associated with decreased HCC risk,with an odds ratio(OR)[95%confidence interval(CI)]of 0.62(0.40-0.95),0.60(0.39-0.92),0.73(0.54-0.98),and 0.58(0.42-0.78),respectively.CCAACG,CCGACG,and TCAATA were significantly associated with decreased frequencies of the HCC-risk HBV mutations:preS1 deletion,APOBECsignature HBV mutations in the core promoter and preS regions,A51C/T,G104C/T,and G146C/T.TCGATA and TTAACG were associated with increased LC risk,with an OR(95%CI)of 1.54(1.03-2.30)and 2.23(1.50-3.33),respectively.However,TCGATA and TTAACG were not consistently associated with the cirrhosis-risk HBV mutations.Conclusion:CCAACG,CCGACG,and TCAATA are inversely associated with HCC risk,possibly because they are involved in creating an immune microenvironment attenuating the generation of HCC-risk HBV mutations.TCGATA and TTAACG might predispose the polarity of immunity towards Th17 isotype related to LC.Yifan Chen Jiansheng Lin Yang Deng Wenbin Liu Zishuai Li Xinyu Zhou Shiliang Cai Rui Pu Jianhua Yin Xiaojie Tan Jun Zhao Xue Han Guangwen Cao 2022Hepatoma Research2022,8,1:2
10In Situ Electrochemical Mn(Ⅲ)/Mn(Ⅳ) Generation of Mn(Ⅱ)O Electrocatalysts for High-Performance Oxygen Reduction显示文摘Among various earth-abundant and noble metal-free catalysts for oxygen reduction reaction(ORR),manganese-based oxides are promising candidates owing to the rich variety of manganese valence.Herein,an extremely facile method for the synthesis of cubic and orthorhombic phase coexisting Mn(Ⅱ)O electrocatalyst as an efficient ORR catalyst was explored.The obtained MnO electrocatalyst with oxygen vacancies shows a significantly elevated ORR catalytic activity with a half-wave potential(E1/2) of as high as 0.895 V,in comparison with that of commercial Pt/C(E1/2=0.877 V).More impressively,the MnO electrocatalyst exhibits a marked activity enhancement after test under a constant applied potential for 1000 s thanks to the in situ generation and stable presence of high-valence manganese species(Mn^3+ and Mn^4+) during the electrochemical process,initiating a synergetic catalytic effect with oxygen vacancies,which is proved to largely accelerate the adsorption and reduction of O_2 molecules favoring the ORR activity elevation.Such an excellent ORR catalytic performance of this MnO electrocatalyst is applied in Zn-air battery,which shows an extra-high peak power density of 63.2 mW cm^-2 in comparison with that(47.4 m W cm^-2) of commercial Pt/C under identical test conditions.Han Tian Liming Zeng Yifan Huang Zhonghua Ma Ge Meng Lingxin Peng Chang Chen Xiangzhi Cui Jianlin Shi 2020Nano-Micro Letters2020,12,11:2
11Susceptibility of patients with chronic obstructive pulmonary disease to heart rate difference associated with the short-term exposure to metals in ambient fine particles:A panel study in Beijing,China显示文摘Susceptibility of patients with chronic obstructive pulmonary disease(COPD)to cardiovascular autonomic dysfunction asso-ciated with exposure to metals in ambient fine particles(PM2.5,particulate matter with aerodynamic diameter≤2.5µm)remains poorly evidenced.Based on the COPDB(COPD in Beijing)panel study,we aimed to compare the associations of heart rate(HR,an indicator of cardiovascular autonomic function)and exposure to metals in PM2.5 between 53 patients with COPD and 82 healthy controls by using linear mixed-effects models.In all participants,the HR levels were significantly associated with interquartile range increases in the average concentrations of Cr,Zn,and Pb,but the strength of the associations differed by exposure time(from 1.4%for an average 9 days(d)Cr exposure to 3.5%for an average 9 d Zn exposure).HR was positively associated with the average concentrations of PM2.5 and certain metals only in patients with COPD.Associations between HR and exposure to PM2.5,K,Cr,Mn,Ni,Cu,Zn,As,and Se in patients with COPD significantly differed from those in health controls.Furthermore,association between HR and Cr exposure was robust in COPD patients.In conclusion,our findings indicate that COPD could exacerbate difference in HR following exposure to metals in PM2.5.Ke Gao Xi Chen Xiaoying Li Hanxiyue Zhang Mengxiao Luan Yuan Yao Yifan Xu Teng Wang Yiqun Han Tao Xue Junxia Wang Mei Zheng Xinghua Qiu Tong Zhu 2022Science China(Life Sciences)2022,65,2:2
12Tacrine-6-Ferulic Acid,a Novel Multifunctional Dimer,Inhibits Amyloid-b-Mediated Alzheimer's Disease-Associated Pathogenesis In Vitro and In Vivo显示文摘Rongbiao Pi X M Xiaojuan Chao Zhiyi Cheng Mengfei Liu Xiaolu Duan Mingzhong Ye X C Zhengrong Mei Peiqing Liu Wenming Li Yifan Han 2012PLo S ONE2012,7,2:1
13Influence of soil density on gas permeability and water retention in soils amended with in-house produced biochar显示文摘Biochar has been used as an environment-friendly enhancer to improve the hydraulic properties(e.g.suction and water retention)of soil.However,variations in densities alter the properties of the soil ebiochar mix.Such density variations are observed in agriculture(loosely compacted)and engineering(densely compacted)applications.The influence of biochar amendment on gas permeability of soil has been barely investigated,especially for soil with different densities.The major objective of this study is to investigate the water retention capacity,and gas permeability of biochar-amended soil(BAS)with different biochar contents under varying degree of compaction(DOC)conditions.In-house produced novel biochar was mixed with the soil at different amendment rates(i.e.biochar contents of 0%,5%and 10%).All BAS samples were compacted at three DOCs(65%,80%and 95%)in polyvinyl chloride(PVC)tubes.Each soil column was subjected to dryingewetting cycles,during which soil suction,water content,and gas permeability were measured.A simplified theoretical framework for estimating the void ratio of BAS was proposed.The experimental results reveal that the addition of biochar significantly decreased gas permeability kg as compared with that of bare soil(BS).However,the addition of 5%biochar is found to be optimum in decreasing kg with an increase of DOC(i.e.k_(g,65%)>k_(g,80%)>k_(g,95%))at a relatively low suction range(<200 kPa)because both biochar and compaction treatment reduce the connected pores.Ankit Garg He Huang Weiling Cai Narala Gangadhara Reddy Peinan Chen Yifan Han Viroon Kamchoom Shubham Gaurav Hong-Hu Zhu 2021Journal of Rock Mechanics and Geotechnical Engineering2021,13,3:1
14Cure characteristics of phenol-formaldehyde resin catalyzed with Ba(OH)2显示文摘He Liangjia Han Renlu Zhang Yifan 2009Journal of Adhesion Science and Technology2009,23,12:1
15In-situ TEM observation of the evolution of helium bubbles & dislocation loops and their interaction in Pd during He^(+) irradiation显示文摘The microstructural evolution of purity Pd under 30 keV He^(+)irradiation at 573 K was investigated by in-situ transmission electron microscopy.The nucleation,growth,merging,annihilation,size change,number density variation,and types of dislocation loops were analyzed under the influence of irradiation fluence and sample thickness.Both perfect dislocation loops with b=1/2<110>and faulted dislocation loops with b=1/3<111>were formed.However,at low irradiation fluence,most of the loops were 1/3<111>loops.The thickness of TEM foil obviously affected the ratio of 1/3<111>loop variants,the size and number density of dislocation loops,and the characteristics of bubble-loop complexes.With the increase of irradiation fluence,the size of dislocation loops increased,but loop volume number density remained almost constant until dislocation loops merged and evolved into dislocation network.There was an obvious interaction between dislocation loops and bubbles,indicating that 1/3<111>loop was first formed at the initial stage of irradiation,and when the loop grew to a certain size,obvious helium bubbles appeared inside its region.Qing Han Yipeng Li Guang Ran Xinyi Liu Lu Wu Yang Chen Piheng Chen Xiaoqiu Ye Yifan Ding Xiaoyong Wu 2021Journal of Materials Science & Technology2021,,28:1
16Study on Flow Characteristics of a Turbulent Boundary Layer and Vortex Structure of High Pressure Guide Vanes in SCO_2 Turbines显示文摘In order to further understand the aerothermodynamic performance and flow loss mechanism of SCO_2 turbines, RANS equations and an SST Turbulence Model were chosen for a numerical study on the secondary flow and vortex structure of cascades using the commercial software CFX. The dimensionless vorticity analysis method was used to study the flow characteristics of the logarithmic layer and viscous sublayer in high pressure guide vane cascades. The new vortex structure and formation mechanism of the vortices were given and analyzed. Simulation results indicated that during the motion of the boundary layer in the cascades, the logarithmic layer and viscous sublayer obtain the different rotational direction vorticity, respectively. The endwall logarithmic layer and pressure side leg of the horseshoe votex gradually develop into the passage vortex, with the endwall viscous sublayer gradually developing into the corner viscous sublayer vortex II and the endwall viscous sublayer vortex I. The endwall viscous sublayer that rolled by the passage vortex is encountered with the upstream-side and radial boundary layer of the vane at the suction separation line, forming the suction separation line vortex beside the passage vortex. A pair of radial transition vortices are formed between the wake and the main stream.HAN Wanlong WANG Yueming FENG Zhenping LI Hongzhi YAO Mingyu ZHANG Yifan 2019Journal of Thermal Science2019,28,3:1
17Structure and reactivity of phosphorous modified H-ZSM-5 catalysts for ethanol dehydration 显示文摘RAMESH K HUI L M HAN YIFAN 2009Catai Commun2009,10,:1
18A biomimetic experimental study of magnesium ion mineralization in Mg-enriched aragonite显示文摘In this work, we test the hypothesis that the Mg2+content in biogenic aragonite has a systematic relationship with biomolecules. A series of biomimetic experiments were conducted to show the dependence of Mg2+in aragonite on the model organic molecules added to the mineralizing solution, including the concentration of various organics, mineralization temperature, Mg/Ca ratio and Mg2+initial concentration. The mineralized products were characterized by powder X-ray diffraction(XRD), Fourier transform infrared spectroscopy(FT-IR), field emission scanning electron microscopy(FESEM), thermogravimetric analysis(TGA), and inductively coupled plasma-atomic emission spectrometry(ICP-AES). High Mg2+is detected in aragonite obtained in the presence of organics, whereas the lowest Mg2+is measured in aragonite without organics. Moreover, the concentration of Mg2+in aragonite increases gradually with the amended organics. Mg K-edge NEXAFS spectra show that the magnesium microenvironment in aragonite is similar to the organic-associated environment, indicating that the Mg2+ions are not on the aragonite lattices, but adhere to the intracrystalline organics. Furthermore, the mineralization temperature, Mg/Ca ratio and Mg2+content in mineralization medium significantly influence Mg2+content in aragonite, reiterating the effect of the microenvironment on aragonite biomineralization.Qizhi YAO Yuying WANG Yifan ZHANG Han LI Gentao ZHOU 2019Science China Earth Sciences2019,62,10:1
19Synthesis, characterization, and catalytic activity of phosphorus modified H-ZSM-5 catalysts in selective ethanol dehydration 显示文摘RAMESH K JIE C HAN YIFAN 2010Ind Eng Chem Res2010,49,:1
20LEO Mega Constellations:Review of Development,Impact,Surveillance,and Governance显示文摘The rapid development of Low Earth Orbit(LEO)mega constellations has significantly contributed to several aspects of human scientific progress,such as communication,navigation,and remote sensing.However,unrestrained deployment of constellations has also strained orbital resources and increased spacecraft congestion in LEO,which seriously affects the safety of in-orbit operations of many space assets.For the long-term and sustainable development of space activities in LEO regions,space environment stability must be maintained using more rational surveillance and governance mechanisms.This review contributes to the research gap and facilitates the development of LEO mega constellations.First,the current development of typical LEO mega constellations is reviewed,followed by the analysis of the impact of LEO mega constellations in terms of astronomical observation,spacecraft safety in orbit,and space environment evolution.Then,two main solutions to conduct the challenges raised by LEO mage constellations are elaborated:one is to ensure the safety operation of spacecraft using space surveillance infrastructures and space situational awareness technologies,and the other is to accelerate the deorbit of constellation satellites at the end of life based on postmission disposal and active removal methods.Finally,the future development and potential research directions of LEO mega constellations are prospected.Jingrui Zhang Yifan Cai Chenbao Xue Zhirun Xue Han Cai 2022Space(Science & Technology)2022,,1:1
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