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Chinese Science Bulletin 2001年第22期46卷 1904-1908页

作者： CAI Yanjun, ZHANG Meiliang, PENG Zicheng, LIN Yushi, AN Zhisheng, ZHANG Zhaofeng & CAO Yunningstate key laboratory of Loess and Quaternary Geology, Institute of Earth Environment, Chinese Academy of Sciences, xi’an 710054, china Karst dynamics laboratory, Ministry of Land and Resources, Guilin 541003, china Department of Earth and Space Science, University of Science & Technology of china, Hefei 230023, china state key laboratory of Loess and Quaternary Geology Institute of Earth Environment Chinese Academy of Sciences Xi’an China Karst dynamics laboratory Ministry of Land and Resources Guilin China Department of Earth and Space Science University of Science & Technology of China Hefei China

A stalagmite from Qixing Cave, Guizhou Province was dated with the TIMS U-series method and its oxygen isotope composition was analyzed. On the basis of the ages and the variations of the δ18O of the stalagmite, the climate change of the last 7.7 ka has been reconstructed in this area: 7.7-5.8 ka, summer monsoon maximum period; 5.8-3.8 ka summer monsoon weakening period; 3.8-0.15 ka, weakened summer monsoon and high amplitude climate fluctuations period. We put forward that the increasing trend of δ18O of the stalagmite reflected not only the weakening of the summer monsoon, which was caused by the decreasing of solar radiation in the Northern Hemisphere, but also the possibly decreasing contribution of the southwest monsoon to the rainfall of this area. These results are consistent with the output of the numerical climate-model modeling. The high amplitude fluctuation of the δ18O may imply the quick shift of the contributions of different moisture sources to the precipitation in this area.

关键词： stalagmite Holocene southwest monsoon.

Effect of aspect ratio of elliptical stirred vessel on mixing time and flow field characteristics in the absence of baffles

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Chinese Journal of Chemical Engineering 2024年第1期65卷 63-74页

作者： Yuan Yao Peiqiao Liu Qian Zhang Zequan Li Benjun xi Changyuan Tao Yundong Wang Zuohua Liu School of Chemistry and Chemical Engineering Chongqing UniversityChongqing 400044China Hubei Three Gorges laboratory Yichang 443007China Department of Chemical Engineering Tsinghua UniversityBeijing 100084China

Elliptical tanks were used as an alternative to circular tanks in order to improve mixing efficiency and reduce mixing time in unbaffled stirred tanks(USTs). Five different aspect ratios of elliptical vessels were designed to compare their mixing time and flow field. Computational fluid dynamics(CFD) simulations were performed using the k–ε model to calculate the mixing time and simulate turbulent flow field features, such as streamline shape, velocity distribution, vortex core region distribution, and turbulent kinetic energy(TKE) transfer. Visualization was also carried out to track the tinctorial evolution of the liquid phase. Results reveal that elliptical stirred tanks can significantly improve mixing performance in USTs. Specifically, the mixing time at an aspect ratio of 2.00 is only 45.3% of the one of a circular stirred tank. Furthermore, the secondary flow is strengthened and the vortex core region increases with the increase of aspect ratio. The axial velocity is more sensitive to the aspect ratio than the circumferential and radial velocity. Additionally, the TKE transfer in elliptical vessels is altered. These findings suggest that elliptical vessels offer a promising alternative to circular vessels for enhancing mixing performance in USTs.

关键词： Mixing time CFD Stirred tank Secondary flow Mixing performance

DMF-scMT-seq linking methylome and transcriptome within single cells with digital microfluidics

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Science china Chemistry 2024年第6期67卷 2070-2078页

作者： xing Xu xi Zeng xin Lin Shiyan Lin Shanshan Liang Tian Tian Rui Su Jia Song Chaoyong Yang Collaborative Innovation Center of Chemistry for Energy Materials The MOE Key Laboratory of Spectrochemical Analysis and InstrumentationState Key Laboratory of Physical Chemistry of Solid SurfacesDepartment of Chemical BiologyCollege of Chemistry and Chemical EngineeringThe First Affiliated Hospital of Xiamen UniversityXiamen UniversityXiamen361005China Institute of Molecular Medicine Renji HospitalShanghai Jiao Tong University School of MedicineShanghai200127China Chemistry and Materials Science College Shanghai Normal UniversityShanghai200234China Chemistry and Biomedicine Innovation Center(ChemBIC) School of Chemistry and Chemical EngineeringNanjing UniversityNanjing210023China

Single-cell joint analysis of methylome and transcriptome reveals how the methylation regulates the transcriptional ***,traditional bench-top protocols for single-cell DNA methylation and RNA transcription co-detection are laborintensive,cost-ineffective and ***,we establish the DMF-sc MT-seq,a highly-efficient and cost-effective method to simultaneously analyze single-cell DNA methylation and transcriptional activity based on digital *** MT-seq automates the workflow of single-cell isolation,cellular hypotonic lysis,nucleic acid separation and methylome/transcriptome library construction in a contactless and addressable *** system ensures high accuracy(R>0.85),high gene detection ability(14,697 genes per cell at 4 million sequencing depth),and high CpG coverage(677,198 CpG sites per cell at 1million sequencing depth).By using DMF-sc MT-seq,the relationship of DNA methylation and RNA transcription under different genomic contexts is *** further apply DMF-sc MT-seq to study the dynamics of transcription regulation with methylation-inhibiting anti-tumor Decitabine,and identify the methylated promoter/gene body driven genes in response to Decitabine ***-sc MT-seq facilitates the construction of the correlation of DNA methylation and transcriptional activity at the single-cell level in a flexible,sensitive and accurate way,which is anticipated to be a powerful tool in studying single-cell biological systems.

关键词： single-cell analysis digital microfluidics methylome sequencing transcriptome sequencing

Engineering design and numerical design for chemical looping combustion reactor: A review

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Energy Reviews 2024年第3期3卷 129-150页

作者： xi Chen Rongchao Li Ye Tao Yongqi Tong Ao Li Daofeng Mei Haibo Zhao state key laboratory of Coal Combustion School of Energy and Power EngineeringHuazhong University of Science and TechnologyWuhan430074China Instituto de Carboquímica(ICB-CSIC) Miguel Luesma Castan450018ZaragozaSpain

Chemical looping combustion(CLC)has emerged as a cost-effective technology for carbon capture at the combustion *** reactor,being central to the implementation of CLC,primarily adheres to two technological pathways:the dual fluidized bed reactor and the packed bed ***,the intricate interaction between gas-solid reaction flow and heat/mass transfer processes in these reactors gives rise to diverse operational principles at both macroscopic and microscopic levels across various reactor forms and scales,making performance prediction ***,the rational design of CLC reactors poses a significant challenge in advancing this technology to commercial *** article offers an extensive review of the prevailing reactor designs in CLC,delving into reactor characteristics,pivotal aspects of the design process,methodologies,and representative studies in the *** predominant reactor design approaches are categorized into engineering and numerical *** former encompasses phenomenological and similarity analysis methods,whereas the latter consists of macroscopic and computational fluid dynamics simulation *** method possesses its theoretical framework,distinctive characteristics,appropriate applications,and respective advantages and *** practical applications,integrating these aspects is *** instance,the engineering design,which is less costly but also less precise,is effective for quickly screening numerous potential design *** contrast,the numerical design,despite its higher computational demand and greater model complexity,offers improved predictive accuracy and is optimal for validating and refining engineering design solutions.

关键词： Carbon capture Chemical looping combustion Reactor design Engineering design Numerical design

Long-term thinning decreases the contribution of heterotrophic respiration to soil respiration in subalpine plantations

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Journal of Forestry Research 2024年第3期35卷 189-204页

作者： Longfei Chen Zhibin He Wenzhi Zhao xi Zhu Qin Shen Mingdan Song Zhengpeng Li Junqia Kong Shuping Yang Yuan Gao Northwest Institute of Eco-Environment and Resources Chinese Academy of SciencesLanzhou 730000People's Republic of China state Forestry Administration key laboratory of Forest Resources and Environmental Management Beijing Forestry UniversityBeijing 100083People's Republic of China Academy of Agriculture and Forestry Sciences Qinghai UniversityXining 810000People's Republic of China College of Landscape Architecture Zhejiang A&F UniversityHangzhou 310000People's Republic of China

Interest in the dynamics of soil respiration(R_(S))in subalpine forest ecosystems is increasing due to their high soil carbon density and potential sensitivity to environmental ***,as a principal silvicultural practice,the long-term impacts of thinning on R_(S) and its heterotrophic and autotrophic respiration components(R_(h) and Ra,respectively)in subalpine plantations are poorly understood,espe-cially in winter.A 3-year field observation was carried out with consideration of winter CO_(2) efflux in middle-aged sub-alpine spruce plantations in northwestern china.A trench-ing method was used to explore the long-term impacts of thinning on Rs,Rn and R_(a).Seventeen years after thinning,mean annual Rs,Rn and R_(a) increased,while the contribu-tion of R_(h) to R_(s) decreased with thinning *** significantly decreased winter R,because of the reduction in R_(n) but had no significant effect on *** temperature sensitivity(Q_(10))of R_(h) and R_(a) also increased with thinning intensity,with lower Q_(10) values for R_(h)(2.1-2.6)than for Ra(2.4-2.8).The results revealed the explanatory variables and pathways related to R_(n) and R_(a) *** increased soil moisture and nitrate nitrogen(NO_(3)^(-)-N),and the enhanced nitrogen and water availability promoted R_(h) and R_(a) by improving fine root biomass and microbial *** results highlight the positive roles of NO_(3)^(-)-N in stimulating R_(s) components following long-term ***,applications of nitrogen fertilizer are not recommended while thinning subalpine spruce plantations from the perspective of reducing soil CO_(2) *** increased Q_(10) values of R_(s) components indicate that a large increase in soil CO_(2) emissions would be expected following thinning because of more pronounced climate warming in alpineregions.

关键词： Heterotrophic respiration Autotrophic respiration Long-term thinning impacts Cold seasons Subalpine plantations Temperature sensitivity

Simulation of molecular dynamics of silver subcritical nuclei and crystal clusters during solidification

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Science china(Technological Sciences) 2010年第12期53卷 3203-3208页

作者： JIAN ZengYun1, CHEN Ji1, CHANG FangE1, ZENG Zhao1, HE Tan1 & JIE WanQi2 1 School of Materials Science and Engineering, xi’an Technological University, xi’an 710032, china 2 state key laboratory of Solidification Processing, Northwestern Polytechnical University, xi’an 710072, china School of Materials Science and Engineering Xi’an Technological University Xi’an China state key laboratory of Solidification Processing Northwestern Polytechnical University Xi’an China

Molecular dynamics simulation is carried out to investigate the effects of cooling rate on the final configurations of silver after rapid solidification. The cooling rate for the formation of a silver amorphous phase is determined by analyzing its pair distribution function, H-A bond index, and the largest crystal cluster. Further, the equilibrium structures of the subcritical nuclei and crystal clusters are studied. The results show that the solidified microstructure is composed of a mixture of crystal clusters and amorphous phases at a certain cooling rate range. The size of the largest crystal cluster decreases with the increasing cooling rate, and it completely disappears when the cooling rate exceeds a critical value. The structures of the subcritical nuclei and the largest crystal cluster are composed of lamellar structures of fcc and hcp atoms, indicating that the lamellar structure of fcc and hcp atoms in the silver crystal originates from nucleation, and not from the growth of crystals.

关键词： molecular dynamics simulation amorphous phase subcritical nuclei crystal cluster cooling rate

Formation of the Yazi Spring Stream and its significance on tectonics-climate on the northern slope of Kunlun Mountains

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Science Bulletin 2005年第18期 97-102页

作者： CHANG Hong1,2, ZHANG Peizhen3, AN Zhisheng1, WANG Xulong1, QIANG xiaoke1 & FU Chaofeng1 1. state key laboratory of Loess and Quaternary Geology, Institute of Earth Environment, Chinese Academy of Sciences, xi’an 710075, china 2. Graduate School of Chinese Academy of Sciences, Beijing 100039, china 3. state key laboratory of Seismic dynamics, china Earthquake Ad-ministration, Beijing 100029, china

The sequences of fluvial terraces in the Yazi Spring Stream are signs of the stepwise uplift of the Kunlun Mountains in the northern part of the Tibetan Plateau since the Late Pleistocene. Geomorphic and sedimentary features of the terraces reveal that they have resulted from the phased tectonic uplift and the consequent river incision in the northern plateau. Using the method of Single-aliquot Regenerative-dose (SAR) Protocol and Radiocarbon 14C dating, the deposit ages of three-grade terraces were ob- tained, which are 57.5, 12.8 and 5.7 kaBP, respectively. The features and ages of terraces reveal that the incision rate of the stream accelerated at the beginning of the Holocene. The incision rate changed suddenly at 12.8 KaBP, from 0.43±0.07 mm/a to 1.59±0.55 mm/a. This implicates that uplift of the Kunlun Mountains is intensive at the first onset of the Holo- cene, corresponding to the obvious change of slip-rate on the Altyn Tagh Fault. But its uplift rate is much lower than that of the latter, which suggests that growth of the northern mar- gin of the Tibetan Plateau is stronger than its interior.

关键词： Tibetan Plateau Kunlun Mountains terrace optically stimulated luminescence tectonic uplift.

Advanced wastewater treatment with microalgae-indigenous bacterial interactions

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Environmental Science and Ecotechnology 2024年第4期20卷 198-207页

作者： Xue Li Shengnan Li Peng xie xi Chen Yuhao Chu Haixing Chang Jian Sun Qing Li Nanqi Ren Shih-Hsin Ho state key laboratory of Urban Water Resource and Environment School of EnvironmentHarbin Institute of TechnologyHarbin150090PR China College of Chemistry and Chemical Engineering Chongqing University of TechnologyChongqing400054PR China Central Southern china Municipal Engineering Design and Research Institute Co. LtdWuhan430010PR China

Microalgal-indigenous bacterial wastewater treatment(MBWT)emerges as a promising approach for the concurrent removal of nitrogen(N)and phosphorus(P).Despite its potential,the prevalent use of MBWT in batch systems limits its broader ***,the success of MBWT critically depends on the stable self-adaptation and synergistic interactions between microalgae and indigenous bacteria,yet the underlying biological mechanisms are not fully *** we explore the viability and microbial dynamics of a continuous flow microalgae-indigenous bacteria advanced wastewater treatment system(CFMBAWTS)in processing actual secondary effluent,with a focus on varying hydraulic retention times(HRTs).The research highlights a stable,mutually beneficial relationship between indigenous bacteria and *** and indigenous bacteria can create an optimal environment for each other by providing essential cofactors(like iron,vitamins,and indole-3-acetic acid),oxygen,dissolved organic matter,and *** collaboration leads to effective microbial growth,enhanced N and P removal,and energy *** study also uncovers crucial metabolic pathways,functional genes,and patterns of microbial ***,the effluent NH4 t-N and P levels complied with the Chinese national Class-II,Class-V,Class-IA,and Class-IB wastewater discharge standards when the HRT was reduced from 15 to 6 *** results,including the highest rates of CO2 fixation(1.23 g L^(-1)),total energy yield(32.35 kJ L^(-1)),and the maximal lipid(33.91%)and carbohydrate(41.91%)content,were observed at an HRT of 15 ***,this study not only confirms the feasibility of CFMBAWTS but also lays a crucial foundation for enhancing our understanding of this technology and propelling its practical application in wastewater treatment plants.

关键词： Continuous flow systems Microalgal-indigenous bacterial interactions Advanced treatment Self-adaptation mechanisms Nutrient removal mechanisms

Research on paleo-fluid potential and chronology by use of inclusions in Santanghu Basin

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Research on paleo-fluid potential and chronology by use of i...

Sr-Nd-Pb isotopes of the Early Paleozoic maficultramafic dykes and basalts from South Qinling belt and their implications for mantle composition

First Meeting Asia Current Research on Fluid Inclusion

作者： Qing Cao, Yiqun Liu, Jianrong Hao Department of Resource Engineering, xi’an Petroleum University, xi’an 710065, china Department of Geology, state key laboratory of Continental dynamics, Northwest University, xi’an 710069, china

Santanghu Basin is located in the north-east of Siberian plate, which is lined-to-lined with Aermantai and Kelamaili tectonic zone and also is the important part of Paleozoic orogenic belt in northern xinjiang. Santanghu Basin is a composite and reconstructive basin and developed on the basis of rift-fault basin of Permian, covered by Permian Series to Quaternary Series. The

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Science china Earth Sciences 2007年第9期50卷 1293-1301页

作者： ZHANG ChengLi1,2, GAO Shan1, 2, YUAN HongLin1, ZHANG GuoWei1, YAN Yunxiang1, LUO JingLan1 & LUO JinHai1 1 state key laboratory of Continental dynamics, Department of Geology, Northwest University, xi’an 710069, china 2 state key laboratory of Geological Progresses and Mineral Resources, china University of Geosciences, Wuhan 430074, china state key laboratory of Continental dynamics Department of Geology Northwest University Xi'an 710069 China state key laboratory of Geological Progresses and Mineral Resources China University of Geosciences Wuhan 430074 China state key laboratory of Continental dynamics Department of Geology Northwest University Xi'an 710069 China

Late Early Paleozoic mafic-ultramafic dykes and volcanic rocks from the South Qinling belt are char- acterized by εNd( t ) = +3.28― +5.02, (87Sr/86Sr)i= 0.70341― 0.70555, (206Pb/204Pb)i = 17.256― 18.993, (207Pb/204Pb)i= 15.505―15.642, (208Pb/204Pb)i=37.125―38.968, ?8/4=21.18―774.43, ?7/4=8.11―18.82. These charac- teristics suggest that they derived from a Middle Neoproterozoic mantle with isotopic compositions of mixed HIMU, EMII and minor EMI components. We interpret that these rocks were melting products of depleted mantle modified by subducted ancient oceanic crust and continental margin sediments along the northern margin of Yangtze block during Early Neoproterozoic.

关键词： mafic dykes Sr-Nd-Pb isotope mantle source South Qinling belt