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Earthquake Engineering and Engineering Vibration 2024年第2期23卷 445-454页

作者： li Yuchun Shen chao liu Wei li Dong Department of Hydraulic Engineering College of Civil EngineeringTongji UniversityShanghai 200092China

The auto-parametric resonance of a continuous-beam bridge model subjected to a two-point periodic excitation is experimentally and numerically investigated in this *** auto-parametric resonance experiment of the test model is conducted to observe and measure the auto-parametric resonance of a continuous beam under a two-point excitation on *** parametric vibration equation is established for the test model using the finite-element *** auto-parametric resonance stability of the structure is analyzed by using Newmark's method and the energy-growth exponent *** effects of the phase difference of the two-point excitation on the stability boundaries of auto-parametric resonance are studied for the test *** with the experiment,the numerical instability predictions of auto-parametric resonance are consistent with the test phenomena,and the numerical stability boundaries of auto-parametric resonance agree with the experimental *** a continuous beam bridge,when the ratio of multipoint excitation frequency(applied to the columns)to natural frequency of the continuous girder is approximately equal to 2,the continuous beam may undergo a strong auto-parametric *** with the present experiment and analysis,a hypothesis of Volgograd Bridge's serpentine vibration is discussed.

关键词： auto-parametric resonance continuous beam bridge model two-point excitation experimental investigation stability analysis vibration of Volgograd Bridge

A Review on Flow Boiling of the Fluid with Lower Boiling Point in Micro-Channels

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Journal of Thermal Science 2024年第1期33卷 1-17页

作者： ZHANG Zhiqiang JIA li DANG chao Beijing Key Laboratory of Flow and Heat Transfer of Phase Changing in Micro and Small Scale School of MechanicalElectronic and Control EngineeringBeijing Jiaotong UniversityBeijing 100044China

With the advancement of micro machining technology,the high-heat-flux removal from miniature electronic devices and components has become an attractive *** boiling in micro-channels is an optimal form of heat transfer and has been widely employed in high-heat-flux cooling *** comprehensively-reviewed article focused on the available recent literatures of experimental investigation regarding the flow boiling heat transfer and unstable behaviors of the fluid with lower boiling point in *** thermal-fluid characteristics and potential heat transfer mechanisms of low-boiling-point fluids flow boiling in different narrow passages were summarized and *** literatures regarding the pressure drop and occurrence of the unstable phenomena existing in two-phase flow boiling process were also *** emphasis was given to the heat transfer enhancement methods as well as instability elimination,and various methods such as modification of surface and channel flow geometries were *** future researches in the field of micro-scale flow boiling were suggested.

关键词： flow boiling lower boiling point fluids mini/micro-channels instabilities enhancement suppression

Establishment of an Iron Deficiency Model by Iron Depletion in Pregnant Rats

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Biomedical and Environmental Sciences 2024年第2期37卷 210-215页

作者： CHEN Xi HAN chao ZHAO Jin Peng SHEN Shi WANG li Yuan REN Shou WANG Tong Lei MA Yan XU Ze chao HUO Jun sheng Key Laboratory of Trace Element Nutrition National Health Commission of the People’s Republic of ChinaNational Institute for Nutrition and HealthChinese Center for Disease Control and PreventionBeijing 100050China

Anemia,a global public health problem,has significant adverse consequences on the cognitive development of children and the work capacity of adults;affecting social and economic ***,roughly 43%of children under five years of age,38%of pregnant women,and 29%of nonpregnant women had *** during pregnancy significantly increases the risk of low birth weight and preterm birth.A 10 g/L increase in hemoglobin has been estimated to decrease the risk of maternal and perinatal mortality by 29%and 28%.

关键词： mortality pregnancy anemia

OsPDR20 is an ABCG metal transporter regulating cadmium accumulation in rice

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Journal of Environmental Sciences 2024年第2期136卷 21-34页

作者： He li chao li Di Sun Zhi Min Yang Department of Biochemistry and Molecular Biology College of Life SciencesNanjing Agricultural UniversityNanjing 210095China

Cadmium(Cd)is a non-essential toxic heavy metal,seriously posing high environmental risks to human *** genetic resources relevant to functional genes is important for understanding the metal absorption and accumulation in crops and bioremediation of Cd-polluted *** study investigated a functionally uncharacterized ATP binding cassette transporter G family(ABCG)gene encoding a Pleiotropic Drug Resistance 20(PDR20)type metal transporter which is localized to the plasma membrane of ***20 was transcriptionally expressed in almost all tissues and organs in lifespan and was strongly induced in roots and shoots of young rice under Cd *** expression of OsPDR20 in a yeast mutant ycf1 sensitive to Cd conferred cellular tolerance with less Cd *** of OsPDR20 by RNA interference(RNAi)moderately attenuated root/shoot elongation and biomass,with reduced chlorophylls in rice grown under hydroponic medium with 2 and 10μmol/L Cd,but led to more Cd accumulation.A field trial of rice grown in a realistic Cd-contaminated soil(0.40 mg/kg)showed that RNAi plants growth and development were also compromised compared to wild-type(WT),with smaller panicles and lower spikelet fertility but little effect on yield of ***,OsPDR20 suppression resulted in unexpectedly higher levels of Cd accumulation in rice straw including lower leaves and culm and *** results suggest that OsPDR20 is actively involved in Cd accumulation and homeostasis in rice *** increased Cd accumulation in the RNAi plants has the potential application in phytoremediation of Cd-polluted wetland soils.

关键词： Rice ABCG transporter Cadmium accumulation Phytoremediation

Spectrum analysis of interval process model and its application in uncertain vibration analysis

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Science China(Technological Sciences) 2024年第8期67卷 2549-2564页

作者： li JinWu JIANG chao NI BingYu State Key Laboratory of Advanced Design and Manufacturing Technology for Vehicle College of Mechanical and Vehicle EngineeringHunan UniversityChangsha 410082China

In recent years, the authors have extended the traditional interval method into the time dimension to develop a new mathematical tool called the “interval process model” for quantifying time-varying or dynamic uncertainties. This model employs upper and lower bounds instead of precise probability distributions to quantify uncertainty in a parameter at any given time point. It is anticipated to complement the conventional stochastic process model in the coming years owing to its relatively low dependence on experimental samples and ease of understanding for engineers. Building on our previous work, this paper proposes a spectrum analysis method to describe the frequency domain characteristics of an interval process, further strengthening the theoretical foundation of the interval process model and enhancing its applicability for complex engineering problems. In this approach, we first define the zero midpoint function interval process and its auto/cross-power spectral density(PSD) functions. We also deduce the relationship between the auto-PSD function and the auto-covariance function of the stationary zero midpoint function interval process. Next, the auto/cross-PSD function matrices of a general interval process are defined, followed by the introduction of the concepts of PSD function matrix and cross-PSD function matrix for interval process vectors. The spectrum analysis method is then applied to random vibration problems, leading to the creation of a spectrum-analysis-based interval vibration analysis method that determines the PSD function for the system displacement response under stationary interval process excitations. Finally, the effectiveness of the formulated spectrum-analysis-based interval vibration analysis approach is verified through two numerical examples.

关键词： interval process spectrum analysis power spectral density(PSD) time-varying uncertainty uncertain vibration analysis

Uncovering the largest negative carbon isotope excursion in Earth history

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Science China Earth Sciences 2024年第3期67卷 885-889页

作者： chao li Haiyang WANG State Key Laboratory of Oil and Gas Reservoir Geology and Exploitation Chengdu University of TechnologyChengdu 610059China Institute of Sedimentary Geology Chengdu University of TechnologyChengdu 610059China Key Laboratory of Deep-time Geography and Environment Reconstruction and Applications of Ministry of Natural Resources Chengdu University of TechnologyChengdu 610059China International Center for Sedimentary Geochemistry and Biogeochemistry Research Chengdu University of TechnologyChengdu 610059China State Key Laboratory of Biogeology and Environmental Geology China University of GeosciencesWuhan 430074China

The carbon cycle plays a pivotal role in regulating Earth’s surface environment through atmospheric-oceanic acid-base and redox processes, functioning as the engine driving the evolution of our planet’s surface. A deep understanding of the carbon cycle’s evolution is thus essential for our understanding of the evolution of our planet’s habitability.

关键词： carbon planet evolution

Accumulation and Fractionation of Rare Earth Elements in a Soil-Wheat System

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Pedosphere 2006年第1期16卷 82-90页

作者： DING Shi-Ming liANG Tao ZHANG chao-sheng WANG li-Jun SUN Qin Nanjing Institute of Geography ＆ limnology Chinese Academy of Sciences Nanjing 210008 （China） Institute of Geographic Sciences and Natural Resources Research Chinese Academy of Sciences Beijing 100101 （ China） Department of Geography and Environmental Change Institute National University of Ireland Galway （Ireland） State Key Laboratory of Pollution Control and Resource Reuse School of the Environment Nanjing University Nanjing 210093 （China）

Time series bioaccumulation of rare earth elements （REEs） in field-grown wheat with and without a dressing of extraneous REE fertilizer at different growth stages and fractionation of REEs during their transport in a soil-wheat system were determined. Time-dependent accumulation of extraneous REEs was found in different parts of wheat. An upward transport of extraneous REEs from roots to shoots under a soil dressing and a downward transport from leaves to roots with a foliar dressing were also observed. Moreover, fractionation of REEs occurred in the soil-wheat system. Compared to the host soil a positive Eu anomaly in the stems and grains as well as heavy REE enrichment in the grains were found. The ability of the different wheat organs to fractionate Eu from the REE series was ranked in the order of sterns 〉 grains 〉 leaves 〉 roots.

关键词： accumulation fractionation rare earth elements wheat

Microwave excited hyperthermy and catalysis of heterostructured Au/Cu–BTA for effective bacteria killing by accelerating charge separation

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Rare Metals 2024年第10期43卷 5186-5201页

作者： Wen-Jing Zhang li-Guo Jin Shui-lin Wu chao-Feng Wang Yu-Feng Zheng Zhao-Yang li Zhen-Duo Cui Hui Jiang sheng-li Zhu Xiang-Mei liu School of Materials Science and Engineering the Key Laboratory of Advanced Ceramics and Machining Technology by the Ministry of Education of ChinaTianjin University Biomedical Materials Engineering Research Center Hubei Key Laboratory of Polymer MaterialsMinistry-of-Education Key Laboratory for the Green Preparation and Application of Functional MaterialsSchool of Materials Science&EngineeringHubei University School of Materials Science and Engineering Peking University School of Health Science and Biomedical Engineering Hebei University of Technology

Deep tissue infections caused by pathogenic bacteria seriously threat the lives of *** this study a smart heterostructured Au/Cu-BTA （BTA=1,2,4,5-benzenetetramine） with microwave （MW） response is synthesized via NaBH4reduction of HAuCl4on the ***/Cu-BTA exhibits excellent hyperthermy and dynamics under MW *** MW thermal mechanism of Au/Cu-BTA is attributed to the excellen dielectric loss and polarization of the heterogeneous ***,the surface energy levels of the Cu-BTA interface alleviate the difficulty of electron hopping through multistage ***,MW can excite Cu-BTA to produce free ***,Au nanoparticles rapidly increase electron transfer and inhibit electron-hole ***,the yields of reactive oxygen species can be enhanced for MW dynamic therapy Consequently,under 10 min of MW irradiation,Au/Cu-BTA killed 99.998%±0.001% of Gram-positive Staphylococcus aureus,99.966%±0.014% of methicillin-resistant Staphylococcus aureus,and 96.871%±0.831% of Gram-negative Pseudomonas *** effective MW bacteria-killing strategy designed in this study shows significant potential for application in the MW-responsive treatment of deep tissue infections without antibiotics.

关键词： Anti-infection Antibacterial Microwave therapy

Characteristics of Bi-2223 HTS Tapes Under Short-Circuit Current Impacts in Hybrid Energy Transmission Pipelines

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CSEE Journal of Power and Energy Systems 2024年第2期10卷 736-745页

作者： Yuguang Sun chao Yin Weizhen li Xinyang li Xiaohua Jiang Department of Electric Engineering Tsinghua UniversityBeijing 100084China

A hybrid energy transmission pipeline is proposed with the aim of long-distance cooperative transmission of electricity and chemical fuels, which is composed of an inner high-temperature superconducting (HTS) power cable and outer liquefied natural gas (LNG) pipeline. The flowing LNG could maintain the operating temperature of the inner HTS power cable within the range of 85 K-90 K, thus the Bi-2223 superconductors in the HTS power cable produce little Joule loss with the transmission current below the critical current. Owing to the advantages of high power density, low transmission losses and economical manufacturing costs, the hybrid energy transmission pipeline is expected to be widely utilized in the near future. In order to ensure the safety of the HTS power cable and explosive LNG in case of short-circuit faults, this paper tests and analyzes the characteristics of Bi-2223 HTS tapes of the Type HT-CA, Type HT-SS and Type H models under short-circuit current impacts at the LNG cooling temperature (85 K-90 K). An experimental platform is designed and established for the ampacity tests of HTS tapes above LN2 cooling temperature (77 K). The AC over-current impact tests at 85 K-90 K are carried out on each sample of Bi-2223 tapes respectively, and the experimental results are analyzed and compared to evaluate their performances under different operating conditions. The results indicate that the Type HT-CA tape can withstand 50 Hz short-circuit current impact with the amplitude of 1108 A (10 times of critical current Ic ) for 100 ms at 90 K, and its resistance is the smallest of the three tested samples under similar current impacts. Therefore, the Type HT-CA Bi-2223 tape is the optimal superconductor of the HTS power cable in the hybrid energy transmission pipeline.

关键词： Bi-2223 high-temperature superconducting(HTS)tape critical current hybrid energy transmission pipeline liquefied natural gas(LNG)cooling temperature short-circuit current impact characteristics

Characterization,Expression Pattern Analysis,and Cellular Localization of Two Homologous MUC2 Genes in Japanese Flounder(Paralichthys olivaceus)

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Journal of Ocean University of China 2024年第4期23卷 1035-1044页

作者： ZHU Ying YANG Xinsheng li Zhengjie li chao School of Marine Science and Engineering Qingdao Agricultural UniversityQingdao 266109China

As a member of mucins family,MUC2 is an important component of mucus,which is characterized by tandem and irregular repeat sequences rich in threonine and *** is strongly expressed by goblet cells that are involved in innate *** flounder is an economically important marine *** this study,two homologous genes of MUC2 were identified,named MUC2-1 and *** on phylogenetic and structural analysis,MUC2-1 and MUC2-2 were clustered in two clades,*** olivaceus MUC2-1 showed a closer relationship with MUC2 in the higher *** healthy tissues were analyzed to determine the expression patterns,and both MUC2 genes showed high expression levels in the gills and *** Edwardsiella tarda challenge,*** MUC2-1 and MUC2-2 both showed significant up-regulated expression in intestine and ***,MUC2-1 was significantly up-regulated in gill cell lines following PGN and polyI:C stimulation,and MUC2-2 was significantly up-regulated in gill cell lines following LPS *** addition,ISH results revealed that MUC2-1 and MUC2-2 showed the same tissue localization in intestine tissues,but displayed different localization in *** siRNA-mediated knockdown of MUC2-1 and MUC2-2 genes in the gill cell lines of Japanese flounder affected the expressions of galnt family genes and smad pathway members that are related to mucosal *** results provided a valuable insight into understanding the functions of MUC2 on mucosal immune system in response to the invasion of bacterial pathogen.

关键词： MUC2 ISH Edwardsiella tarda Paralichthys olivaceus