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Six million Q factor micro fused silica shell resonator with teeth-like tines released by femtosecond laser-assisted chemical etching

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science china(Technological sciences) 2024年第6期67卷 1923-1932页

作者： ZHAO Tao SHI Yan LU Kun xi xiang WU XueZhong xiAO DingBang College of Intelligence science and Engineering National University of Defense TechnologyChangsha410073China

The quality factor(Q factor)is a crucial performance parameter for *** this paper,a novel release method for highquality micro fused silica shell resonators with teeth-like tines with good surface morphology is *** method is based on femtosecond laser-assisted chemical ***,the optimal energy range of femtosecond laser modification is obtained through mechanism ***,the optimal parameters for a straight line and arc pattern are determined by optimizing the average output power,processing speed,and processing *** results demonstrate why edge breakage in rounded corners is easy under different ***,according to these conclusions,the processing is performed on a micro fused silica shell resonator with a Q factor exceeding 6 *** addition,subsurface damage is rare throughout the fabrication process,and the surface roughness of the released cross section reaches the nanometer *** improved Q factor helps suppress mechanical thermal noise and reduce zero bias and zero bias drift,constituting the primary method for enhancing the performance of the resonant gyroscope.

关键词： micro hemispherical resonator fused silica laser-assisted chemical etching quality factor

Geochemical Characteristics and Development Significances of Constant and Trace Elements from Coalbed Methane Co-Produced Water:A Case Study of the Shizhuangnan Block,the Southern Qinshui Basin

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Journal of Earth science 2024年第1期35卷 51-61页

作者： Yang Li Shuheng Tang Jian Chen Songhang Zhang Zhaodong xi Key Laboratory of Universities in Anhui Province for Prevention of Mine Geological Disasters Anhui University of Science and TechnologyHuainan 232001China School of Earth and Environment Anhui University of Science and TechnologyHuainan 232001China National Key Laboratory of Petroleum Resources and Engineering China University of PetroleumBeijing 102249China School of Energy Resource China University of GeosciencesBeijing 100083China Key Laboratory of Marine Reservoir Evolution and Hydrocarbon Enrichment Mechanism Ministry of EducationBeijing 100083China Key Laboratory of Strategy Evaluation for Shale Gas Ministry of Land and ResourcesBeijing 100083China

As an unconventional natural gas resource,coalbed methane(CBM)development releases a large amount of CBM wells co-produced *** characteristics of the co-produced water provide an essential foundation for the production dynamics of CBM reservoirs if the impacts of fracturing fluids and other aquifers can be *** the Shizhuangnan Block of the southern Qinshui Basin,constant and trace elements in CBM co-produced water from the wellheads were collected and determined,which is applied to assess water source,fracturing fluid effect,and CBM *** on principle component analysis and hierarchical clustering analysis,the water samples are divided into four *** suggests that different characteristics affected by water-rock interaction,reservoir environment,aquifer recharge,and hydraulic fracturing result in the various ratios of Na^(+)/Cl^(-),alkalinity(HCO_(3)^(-)+CO_(3)^(2-))/Cl^(-)and other specific ***,Cl^(-)is selected as a dividing line for complete fracturing fluid flow back,associated with organic-bound chlorine complexes in the original coal seam *** to constant elements,there is a significant correlation between Li and Sr concentrations and CBM productivity,so templates regarding trace elements can be used to distinguish various sources of the co-produced water.

关键词： coalbad methane CBM co-produced water hydraulic fracturing Qinshui Basin

Emerging clinical relevance of microbiome in cancer:promising biomarkers and therapeutic targets

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Protein & Cell 2024年第4期15卷 239-260页

作者： Jia-Hao Dai xi-Rong Tan Han Qiao Na Liu State Key Laboratory of Oncology in South china Guangdong Key Laboratory of Nasopharyngeal Carcinoma Diagnosis and TherapyGuangdong Provincial Clinical Research Center for CancerSun Yat-sen University Cancer CenterGuangzhou 510050China

The profound influence of microbiota in cancer initiation and progression has been under the spotlight for years,leading to numerous researches on cancer microbiome entering clinical *** promising biomarkers and therapeutic targets,the critical involvement of microbiota in cancer clinical practice has been increasingly ***,recent progress in this field is *** describe the potential of tumor-associated microbiota as effective diagnostic and prognostic biomarkers,*** addition,we highlight the relationship between microbiota and the therapeutic efficacy,toxicity,or side effects of commonly utilized treatments for cancer,including chemotherapy,radiotherapy,and *** that microbial factors influence the cancer treatment outcome,we further summarize some dominating microbial interventions and discuss the hidden risks of these *** review aims to provide an overview of the applications and advancements of microbes in cancer clinical relevance.

关键词： microbiome cancer diagnosis prognosis therapy

Predication of Selective Ring-opening Hydrogenolysis for Furfuryl Alcohol to Produce Pentanediol over Dual-atom Catalysts

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Chemical Research in Chinese Universities 2024年第1期40卷 55-63页

作者： WANG Tingting WANG Jia xi Yongjie HU Bin LI Fuwei State Key Laboratory for Oxo Synthesis and Selective Oxidation Lanzhou Institute of Chemical PhysicsChinese Academy of SciencesLanzhou 730000P.R.China university of Chinese Academy of sciences Beijing 100049P.R.China

Selective activation of C-O bond is of fundamental importance in the precise conversion of oxygenates into value-added compounds in an atom-economic and sustainable manner, and meanwhile, the structurally well-defined dual-atoms catalysts (DACs) have been scarcely investigated in this field. In this study, a series of transition metal DACs anchored on nitrogen-doped graphene (TM2/NC, TM=Pt, Ir, Rh, Pd, Ru, Co, Ni and Cu) was constructed to make a comprehensive investigation of their selectivity in the hydrogenative transformation of furfuryl alcohol (FAL), an important biomass platform molecule, to 1,2-pentanediol (1,2-PeD) via selective cleavage of furanic C5-O bond, by density functional theory (DFT) calculations and microkinetic modeling. We found that Ir2/NC demonstrated a high selectivity for the cleavage of furanic C5-O bond to produce 1,2-PeD, while the production of THFAL or 1,5-pentanediol (1,5-PeD) on other TM2/NC catalysts are more favorable. Furthermore, we found that the selective C-O bond cleavage of FAL furan ring is affected by the orbital overlap between the d-orbitals of the anchored metal atoms and the p-orbitals of the adsorbed C atom in FAL, suggesting that the selectivity of the C-O bond cleavage is inextricably related with the electronic property of the anchored metals.

关键词： Furfuryl alcohol Hydrogenation Dual-atom catalyst Density functional theory(DFT)calculation

Structural Characteristics and Influencing Factors of Carbon Emission Spatial Association Network:A Case Study of Yangtze River Delta City Cluster,china

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Chinese Geographical science 2024年第4期34卷 689-705页

作者： BI xi SUN Renjin HU Dongou SHI Hongling ZHANG Han School of Economics and Management China University of Petroleum(Beijing)Beijing 102249China china Petroleum Planning&Engineering Institute Beijing 100083China

City cluster is an effective platform for encouraging regionally coordinated *** reduction of carbon emissions within city cluster via the spatial association network between cities can help coordinate the regional carbon emission management,realize sustainable development,and assist china in achieving the carbon peaking and carbon neutrality *** paper applies the improved gravity model and social network analysis(SNA)to the study of spatial correlation of carbon emissions in city clusters and analyzes the structural characteristics of the spatial correlation network of carbon emissions in the Yangtze River Delta(YRD)city cluster in china and its influencing *** results demonstrate that:1)the spatial association of carbon emissions in the YRD city cluster exhibits a typical and complex multi-threaded network *** network association number and density show an upward trend,indicating closer spatial association between cities,but their values remain generally ***,the network hierarchy and network efficiency show a downward trend but remain high.2)The spatial association network of carbon emissions in the YRD city cluster shows an obvious‘core-edge’distribution *** network is centered around Shanghai,Suzhou and Wuxi,all of which play the role of‘bridges’,while cities such as Zhoushan,Ma'anshan,Tongling and other cities characterized by the remote location,single transportation mode or lower economic level are positioned at the edge of the network.3)Geographic proximity,varying levels of economic development,different industrial structures,degrees of urbanization,levels of technological innovation,energy intensities and environmental regulation are important influencing factors on the spatial association of within the YRD city ***,policy implications are provided from four aspects:government macro-control and market mechanism guidance,structural characteristics of the‘core-edge’network,reconfigura

关键词： carbon emission spatial association network social network analysis(SNA) quadratic assignment procedure(QAP)model Yangtze River Delta city cluster china

Impacts of multi-foulings on salinity gradient energy conversion process in negatively charged conical nanochannels

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science china(Technological sciences) 2024年第6期67卷 1714-1726页

作者： MAO RuiJie CHEN xi ZHOU RuHong LONG Rui LIU ZhiChun LIU Wei School of Energy and Power Engineering Huazhong University of Science and TechnologyWuhan430074China china-EU Institute for Clean and Renewable Energy Huazhong University of Science and TechnologyWuhan430074China School of Mechanical science and Engineering Huazhong University of Science and TechnologyWuhan430074China

Membrane fouling inevitably occurs during nanofluidic reverse ***,the impact of multi-fouling on the energy conversion performance of negatively charged conical nanochannels under asymmetrical configurations is systematically *** results reveal that in Configuration I,where a high-concentration solution is applied at the tip side,at small concentration ratios,multiple foulings reduce the electric *** Configuration II,where a low-concentration solution is applied at the tip side,multiple foulings near the base side contribute to the electric *** fouling that formed near the lowconcentration entrance diminished the electric power and energy conversion ***-fouling lowered the electrical power consumption by 69.27%and 99.94%in Configurations I and II,*** Configuration I,the electric power first increased with increasing fouling surface charge density,reached its maximum value,and thereafter *** Configuration II,the electric power first decreased with increasing fouling surface charge density,reached its minimum value,and thereafter *** negative or positive charge densities of fouling contribute to the electric power and energy conversion efficiency.

关键词： conical nanochannel fouling nanofluidic reverse electrodialysis salinity gradient energy

Effect of Incoming Vortex on Secondary Flows in Turbine Cascades with Planar and Non-Axisymmetric Endwall

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Journal of Thermal science 2024年第1期33卷 138-157页

作者： CAO Zhiyuan WANG Chuxuan SONG Zhigao GAO xi ZHAO Wei LIU Bo School of Power and Energy Northwestern Polytechnical UniversityXi'an 710072China National Key Laboratory of science and Technology on Aerodynamic Design and Research Northwestern Polytechnical UniversityXi'an 710072China Institute of Engineering Thermophysics Chinese Academy of SciencesBeijing 100080China School of Aeronautics and Astronautics University of Chinese Academy of SciencesBeijing 100080China

Non-Axisymmetric Endwall Profiling(NAEP) is commonly utilized in turbines to eliminate secondary ***,most of the NAEP methods consider a single-blade row environment without incorporating the effect of the stage *** paper aims to investigate the influence mechanism of the incoming vortex on the endwall secondary flow structures of NAEP in a highly loaded turbine *** model the incoming vortex in a stage environment,this study considers a half-delta wing as the vortex generator at the upstream of the turbine *** NAEP is then carried out for a highly loaded turbine cascade with an in-house numerical optimization design platform subject to no incoming *** simulation is also carried out under the influence of the incoming vortex for the turbine cascades with both planar and non-axisymmetric *** paper furthers investigated the pitchwise effect of the incoming vortex on the near endwall secondary *** results indicate that the NAEP effectively improves the endwall secondary flow of the turbine cascade,where the total pressure loss coefficient and the secondary kinetic energy(SKE) are reduced by 7.3%,and 45.7%,*** is further seen that with the incoming vortex,the NAEP achieves a considerable control effect on the endwall secondary flow of the turbine *** incoming vortex,the NAEP can still achieve considerable control effect on the endwall secondary flow of the turbine cascade;the averaged reductions of loss coefficient and SKE are 7.8% and 14.2%,*** some pitchwise locations,incoming vortex can suppress the convection of cross-passage flow toward the suction corner greatly and reduce the loss coefficient of the baseline *** incoming vortex at 4/7 pitch impinged right at the blade leading edge,leading to the generation of low-momentum fluid,which increased the size and the strength of the horseshoe *** all the pitchwise locations,NAEP can suppress the seco

关键词： non-axisymmetric endwall secondary flow incoming vortex passage vortex stage environment

A comprehensive comparison of different regression techniques and nature-inspired optimization algorithms to predict carbonation depth of recycled aggregate concrete

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Frontiers of Structural and Civil Engineering 2024年第1期18卷 30-50页

作者： Bin xi Ning ZHANG Enming LI Jiabin LI Jian ZHOU Pablo SEGARRA Department of Civil and Environmental Engineering Politecnico Di MilanoMilano 20133Italy Leibniz Institute of Ecological Urban and Regional Development(IOER) Dresden 01217Germany Universidad Politécnica de Madrid-ETSI Minas y Energía Madrid 28003Spain Department of Civil Engineering KU Leuven CampusBrugge 8200Belgium School of Resources and Safety Engineering Central South UniversityChangsha 410083China

The utilization of recycled aggregates(RA)for concrete production has the potential to offer substantial environmental and economic ***,RA concrete is plagued with considerable durability concerns,particularly *** advance the application of RA concrete,the establishment of a reliable model for predicting the carbonation is *** the one hand,concrete carbonation is a long and slow process and thus consumes a lot of time and energy to *** the other hand,carbonation is influenced by many factors and is hard to *** this,this paper proposes the use of machine learning techniques to establish accurate prediction models for the carbonation depth(CD)of RA *** types of regression techniques and meta-heuristic algorithms were employed to provide more alternative predictive *** was found that the best prediction performance was obtained from extreme gradient boosting-multi-universe optimizer(XGB-MVO)with R^(2) value of 0.9949 and 0.9398 for training and testing sets,***-MVO was used for evaluating physical laws of carbonation and it was found that the developed XGB-MVO model could provide reasonable predictions when new data were *** also showed better generalization capabilities when compared with different models in the ***,this paper emphasizes the need for sustainable solutions in the construction industry to reduce its environmental impact and contribute to sustainable and low-carbon economies.

关键词： recycled aggregate concrete carbonation depth nature-inspired optimization algorithms extreme gradient boosting technique parametric analysis

In-situ TEM study of the effect of hydrogen-helium ratio on defect characteristics in Fe9Cr1.5W0.4Si F/M steel during H_(2)^(+)&He^(+)simultaneous irradiation

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Journal of Materials science & Technology 2024年第6期173卷 192-201页

作者： Dewang Cui Ziqi Cao Kun He Yuanming Li xi Qiu Guang Ran College of Energy Xiamen UniversityXiamen 361102China Fujian Provincial Nuclear Energy Engineering Technology Research Center Xiamen 361102China science and Technology on Reactor Fuel and Materials Laboratory Chengdu 610041China Nuclear Power Institute of china Chengdu 610041China science and Technology on Reactor System Design Technology Laboratory Chengdu 610041China

The effect of hydrogen and helium interaction,especially H-He ratio,on the irradiation behavior of nuclear materials has not yet been ***,this is an important basis for evaluating the irradiation properties of nuclear materials and developing high irradiation resistant ***,30 keV H_(2)^(+)and He^(+)dual beams with four H-He ratios of 0:10,3:10,15:10,and 30:10 were used to irradiate the newly developed Fe9Cr1.5W0.4Si F/M steel in TEM to in-situ study the interaction and ratio effect of hydrogen and *** addition of H atoms significantly promoted the nucleation of dislocation loops and *** the early stage of irradiation,the average size and density of dislocation loops increased with the increase of H-He ***,the larger the H-He ratio,the easier it was to form a complex dislocation ***,the final saturation size of bubbles increased with the increase of H-He *** was first found that the swelling was affected by H concentrations,with high H concentrations slowing down the increase in *** a certain irradiation dose,a specific H-He ratio would lead to a swelling peak of Fe9Cr1.5W0.4Si F/M *** super-sized bubbles at grain boundaries(GBs)were found after H addition,resulting in a bigger swelling of GBs than the *** the swelling of the GBs and the matrix show a dependence on the H-He *** current work is of great significance for understanding the interaction between hydrogen and helium in nuclear materials.

关键词： Dose ratio effect Ferritic-martensitic steel Hydrogen&helium synergetic irradiation In-situ TEM