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温度对黄喉拟水龟稚龟生长的影响

暨南大学学报（自然科学与医学版） 2005年第3期26卷 422-427页

作者：李贵生暨南大学生物工程学系广东广州510632

　目的:通过研究黄喉拟水龟稚龟在不同温度下的生长情况,了解温度与龟的生长关系,为龟类的人工养殖提供理论依据.方法:两组龟分别在恒温与室内常温条件下饲养165d,每隔5d测量其体质量、背甲长、背甲宽和体厚,然后进行统计学分析.结果:... 详细信息

　目的:通过研究黄喉拟水龟稚龟在不同温度下的生长情况,了解温度与龟的生长关系,为龟类的人工养殖提供理论依据.方法:两组龟分别在恒温与室内常温条件下饲养165d,每隔5d测量其体质量、背甲长、背甲宽和体厚,然后进行统计学分析.结果:实验结束时,恒温越冬的稚龟平均背甲长为53 420mm,背甲宽为44 761mm,体厚为23 307mm,体质量为29 768g,日增质量为0 193g,存活率为100%.常温越冬的稚龟平均背甲长为47 185mm,背甲宽为39 868mm,体厚为20 023mm,体质量17 304g,日增质量为0 025g,存活率为90%.两组稚龟的体质量与背甲长、体质量与背甲宽、体质量与体厚、背甲长与背甲宽、背甲长与体厚以及背甲宽与体厚之间均存在着显著的正相关关系.常温下体质量的生长模式为:m=18 4822-0 0642D+0 004D2;恒温下体质量的生长模式为:m=17 273337e0 005982D.在同等条件下,稚龟个体间的生长也有差异.结论:温度与龟的生长有密切关系,加温可以促进龟的生长.

关键词：黄喉拟水龟恒温常温

Research,application and development of inorganic binder for casting process

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China Foundry 2024年第5期21卷 461-475页

作者： Xiao-long Gong sheng-li Hu Zi-tian Fan State Key Laboratory of Materials Processing and Die&Mould Technology School of Materials Science and EngineeringHuazhong University of Science and TechnologyWuhan 430074China School of Materials Science and Engineering Wuhan University of TechnologyWuhan 430070China

Inorganic binder used in casting process has the advantages of low odor,labor-friendly conditions,and relatively low cost,which is one of the main development directions for casting molding materials in the ***,compared to organic binders(such as resin binders),inorganic binders exhibit lower bonding strength and are more sensitive to environmental *** sensitivity poses challenges,particularly in the reclamation of used sand,thus limiting their broader *** this paper,the research and application status of inorganic binders(mainly silicate inorganic binders)and their curing methods are *** addition,the research and application of phosphate inorganic binders and 3D printing inorganic binders that are being developed are ***,a detailed comparative analysis is conducted on the challenging issue of“reclamation for used sand”in the application of inorganic ***,the development direction of inorganic binders is clarified.

关键词： inorganic binder silicate system phosphate system 3D printing used sand reclamation development trend

源流·仪式·功能:民俗学视野下的“凉州贤孝”

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华南农业大学学报（社会科学版） 2009年第1期8卷 129-135页

作者：李贵生河西学院中文系甘肃张掖734000

"凉州贤孝"是一种起源很早的民间说唱艺术,无论思想内容还是艺术形式都与敦煌变文有一定的渊源关系。宋元以后,民间艺人在题材和主题上对古凉州民间说唱艺术进行改编,逐渐形成了以表现"贤"与"孝"为主题的新曲目,同时也保留了因果报应、... 详细信息

"凉州贤孝"是一种起源很早的民间说唱艺术,无论思想内容还是艺术形式都与敦煌变文有一定的渊源关系。宋元以后,民间艺人在题材和主题上对古凉州民间说唱艺术进行改编,逐渐形成了以表现"贤"与"孝"为主题的新曲目,同时也保留了因果报应、转世轮回等佛教思想。"凉州贤孝"大多是由盲人用凉州方言演唱,主要用三弦和二胡伴奏,内容包括"家书"、"国书"和一些杂调。"凉州贤孝"具有文化传承、教化、娱乐、宣泄、沟通等多种社会功能。

关键词：凉州贤孝源流仪式功能

Snowpack variations and their hazardous effects under climate warming in the central Tianshan Mountains

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Advances in Climate Change Research 2024年第3期15卷 442-451页

作者： Jian-sheng HAO Yan WANG Lan-Hai li Key Laboratory of Land Surface Pattern and Simulation Institute of Geographic Sciences and Natural Resources ResearchChinese Academy of Sciences(CAS)Beijing 100101China Xinjiang Key Laboratory of Water Cycle and Utilization in Arid Zone Urumqi 830011China State Key Laboratory of Desert and Oasis Ecology Xinjiang Institute of Ecology and GeographyChinese Academy of SciencesUrumqi 830011China Tianshan Snowcover and Avalanche Observation and Research Station of Xinjiang Xinyuan 835800China CAS Research Center for Ecology and Environment of Central Asia Urumqi 830011China

Climate change alters snowpack evolution,which in turn influences the likelihood of snow avalanches and flood *** lack of systemic observational data on key snow characteristics in high mountains remains a scientific challenge in terms of systematically elucidating the dynamic chain of variations in climate-snowpack-snow *** restricts our understanding and poses challenges in the prediction of snow-related disaster *** such,this study analysed the variations of temperature and snowfall and the physical characteristics of snowpacks based on ground-based observations from the Kunse River Valley situated in the Tianshan Mountains from 1967 to *** results reveal that the temperature increased significantly by 0.32°C per decade(plier ***,average and maximum snow depths increased along with an increase in peak snow water equivalent,thus indicating a higher frequency of extremely scarce or abundant snow *** low snowpack temperature gradient and earlier snowmelt dates in spring lead to earlier occurrences of snowmelt floods and wet *** the risks of these events increase,they pose greater threats to farmlands,road transportation,water-electricity infrastructure and several other human ***,these insights are critical for providing vital information that can deepen our understanding of the impact of climate change on snowpack characteristics and improve management strategies for snow-related disaster prevention and mitigation.

关键词： Climate change Snowpack variations Snow-related disaster Tianshan Mountains

Solvent-free carbon sphere nanofluids towards intelligent lubrication regulation

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Friction 2024年第1期12卷 95-109页

作者： sheng ZHANG Wen li Xiaoliang MA Xiaoqiang FAN Minhao ZHU Tribology Research Institute School of Mechanical EngineeringSouthwest Jiaotong UniversityChengdu 610031China Key Laboratory of Advanced Technologies of Materials Ministry of EducationSchool of Materials Science and EngineeringSouthwest Jiaotong UniversityChengdu 610031China

By simply switching the electrical circuit installed on steel/steel contact,the tribological behaviors of nanofluids(NFs)can be regulated in real time,thereby achieving the desired performance of friction reduction and wear ***,solvent-free carbon spherical nanofluids(C-NFs)were successfully prepared for intelligent lubrication regulation.C-NFs with excellent lubrication performance can immediately reduce the coefficient of friction(COF)despite applying a weak electric potential(1.5 V).Moreover,polyethylene glycol 400(PEG400)containing 5.0 wt%C-NFs remained responsive to electrical stimulation under the intermittent voltage application with an average coefficient of friction(ACOF)reduction of 20.8%over *** intelligent lubrication regulation of C-NFs under an external electric field(EEF)mainly depends on the orderly arranged double-electric adsorption film of ion canopy-adsorbed carbon spheres(CSs).The intermittent electrical application can continuously reinforce the adsorption film and its durability for real-time controlling the sliding ***-stimulation-responsive intelligent lubricants provide a new technical support for realizing intelligent stepless control of devices.

关键词： solvent-free carbon spherical nanofluids(C-NFs) intelligent lubrication regulation lubrication performance adsorption film

A CSMA/CA based MAC protocol for hybrid Power-line/Visible-light communication networks:Design and analysis

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Digital Communications and Networks 2024年第2期10卷 481-497页

作者： sheng Hao Huyin Zhang Fei Yang Chenghao li Jing Wang School of Computer Science Central China Normal UniversityWuhan430079PR China Hubei Key Laboratory of intelligent Robot(Wuhan Institute of Technology) Wuhan430079PR China School of Computer Science Wuhan UniversityWuhan430079China School of Information Science and Engineering Shandong Normal UniversityJinan250000China School of Computer Science Hubei University of TechnologyWuhan430079China

Hybrid Power-line/Visible-light Communication(HPVC)network has been one of the most promising Cooperative Communication(CC)technologies for constructing Smart Home due to its superior communication reliability and hardware *** research on HPVC networks focuses on the performance analysis and optimization of the Physical(PHY)layer,where the Power line Communication(PLC)component only serves as the backbone to provide power to light Emitting Diode(LED)*** designing a Media Access Control(MAC)protocol remains a great challenge because it allows both PLC and Visible light Communication(VLC)components to operate data transmission,i.e.,to achieve a true HPVC network *** solve this problem,we propose a new HPC network MAC protocol(HPVC MAC)based on Carrier Sense Multiple Access/Collision Avoidance(CSMA/CA)by combining IEEE 802.15.7 and IEEE 1901 ***,we add an Additional Assistance(AA)layer to provide the channel selection strategies for sensor stations,so that they can complete data transmission on the selected channel via the specified CSMA/CA mechanism,*** on this,we give a detailed working principle of the HPVC MAC,followed by the construction of a joint analytical model for mathematicalmathematical validation of the HPVC *** the modeling process,the impacts of PHY layer settings(including channel fading types and additive noise feature),CSMA/CA mechanisms of 802.15.7 and 1901,and practical configurations(such as traffic rate,transit buffer size)are comprehensively taken into ***,we prove the proposed analytical model has the ***,through extensive simulations,we characterize the HPVC MAC performance under different system parameters and verify the correctness of the corresponding analytical model with an average error rate of 4.62%between the simulation and analytical results.

关键词： Hybrid power-line/Visible light communication (HPVC)networks MAC protocol CSMA/CA IEEE 802.15.7 IEEE 1901 Performance analysis

Circ_0012152 Accelerates Acute Myeloid Leukemia Progression through the miR-652-3p/SOX4 Axis

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Current Medical Science 2024年第3期44卷 611-622页

作者： Ying CHEN Bi-xia li Ting-ting NIU Shu-jun YANG li-chao WU Le-huai SHI Duo-bing ZOU Ning-ning WU li-xia sheng Xiao YAN gui-fang OUYANG Qi-tian MU Laboratory of Stem Cell Transplantation The First Affiliated Hospital of Ningbo UniversityNingbo315300China Ningbo Clinical Research Center For Hematologic Malignancies Ningbo315300China Department of Hematology The First Affiliated Hospital of Ningbo UniversityNingbo315300China School of Medicine Hangzhou City UniversityZhejiang UniversityHangzhou310000China Key Laboratory of Precision Medicine for Atherosclerotic Diseases of Zhejiang Province Ningbo315300China

Objective Acute myeloid leukemia(AML)is an aggressive hematological malignancy characterized by abnormal myeloid blast *** studies have demonstrated that circular RNAs play a role in AML *** this study,we aimed to investigate the clinical significance of circ_0012152 in AML and elucidate its underlying molecular mechanism in the pathogenesis of this *** Circ_0012152 expression was detected by quantitative real-time polymerase chain reaction in samples obtained from 247 patients with AML and 40 healthy controls.A systematic analysis of clinical characteristics and prognostic factors was also *** growth was assessed using the Cell Counting Kit-8(CCK-8)assay,and apoptosis and cell cycle progression were evaluated by flow ***,RNA pull-down was performed to identify target microRNAs,and transcriptome RNA sequencing and bioinformatics analyses were utilized to identify downstream mRNA *** Circ_0012152 was significantly upregulated in samples from patients with AML and served as an independent adverse prognostic factor for overall survival(OS)(hazard ratio:2.357;95%confidence interval 1.258–4.415).The circ_0012152 knockdown reduced cell growth,increased apoptosis,and inhibited cell cycle progression in AML cell *** pull-down and sequencing identified miR-652-3p as a target microRNA of circ_*** growth inhibition by circ_0012152 knockdown was significantly relieved by miR-652-3p *** suggested that miR-652-3p targeted SOX4,as the decrease in SOX4 expression resulting from circ_0012152 knockdown was upregulated by miR-652-3p inhibitors in AML *** Circ_0012152 is an independent poor prognostic factor for OS in AML,and it promotes AML cell growth by upregulating SOX4 through miR-652-3p.

关键词： acute myeloid leukemia circ_0012152 miR-652-3p SOX4 cell growth

Phosphine/Benzocyclone-based Neutral Nickel Catalysts for Ethylene Polymerization and Copolymerization with Polar Monomers

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Chinese Journal of Polymer Science 2024年第2期42卷 202-212,I0007页

作者： Fei Wang li Pan Vladislav A.Tuskaev Svetlana Ch.Gagieva Yue-sheng li Tianjin Key Lab of Composite&Functional Materials School of Material Science and EngineeringTianjin UniversityTianjin300072China Department of Chemistry Lomonosov Moscow State UniversityRussian Federation InstitutionLeninskie Gory 1Moscow119991Russian Federation A N Nesmeyanov Institute of Organoelement Compounds Russian Academy of SciencesVavilova st.28Moscow119991Russian Federation

The efficient copolymerization of olefin with polar monomers using nickel-based catalysts presents a longstanding challenge. In this contribution, three phosphine-benzocyclone ligands and corresponding neutral nickel catalysts(Ni1: Ar = Ph;Ni2: Ar = 2-(C_(6)H_(5))C_(6)H_(4);Ni3: Ar = 2-[2',6'-(Me O)_(2)-C_(6)H3]C_(6)H_(4)) were prepared and applied for the ethylene polymerization and copolymerization with polar monomers without any cocatalyst. The bulky substituent groups in complexes Ni2 and Ni3 contributed to high catalytic activities(up to 7.24×10^(6) and 9.04×10^(6)g·mol Ni^(-1)·h^(-1), respectively), and produced high-molecular-weight polyethylene(Mw up to 545.7 k Da). Complex Ni3 exhibited high activities for ethylene polymerization at the level of 10^(6) g·mol Ni^(-1)·h^(-1) across a wide range from 30 ℃ to 120 ℃, exhibiting excellent high temperature tolerance. These nickel complexes were also effectively employed in the copolymerization of ethylene with methyl acrylate, ethyl acrylate, butyl acrylate and lauryl acrylate, producing copolymers with high molecular weights(Mw up to 80.5 k Da) and high polar monomer incorporation(up to 8.2 mol%). Microstructure analyses revealed that the introduction of large sterically hindered substituents facilitated the incorporation of polar functional units into the polymer backbone. This study demonstrates the potential of these nickel-based catalysts for efficient copolymerization of olefin with polar monomers.

关键词： Neutral nickel catalyst Ethylene polymerization Copolymerization Polar acrylate monomers

InSAR-derived surface deformation characteristics and mining subsidence parameters in mountain coal mines

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Journal of Mountain Science 2024年第9期21卷 3139-3156页

作者： JIANG Xiaowei SHI Wenbing liANG Feng gui Jingjing li Jiawei Key Laboratory of Karst Georesources and Environment Ministry of EducationGuizhou UniversityGuiyang 550025China College of Resources and Environmental Engineering Guizhou UniversityGuiyang 550025China Mountain Geohazard Prevention R&D Center of guizhou Province Guiyang 550025China

Mining-induced surface deformation disrupts ecological balance and impedes economic *** study employs SBAS-InSAR with 107-view of ascending and descending SAR data from Sentinel-1,spanning February 2017 to September 2020,to monitor surface deformation in the Fa’er Coal Mine,guizhou *** on the surface deformation time series reveals the relationship between underground mining and surface *** geological conditions,mining activities,duration,and ranges,the study determines surface movement parameters for the coal *** asserts that mining depth significantly influences surface movement parameters in mountainous mining *** mining depth elevates the strike movement angle on the deeper side of the burial depth by 22.84°,while decreasing by 7.74°on the shallower *** movement angles decrease by 4.06°,while downhill movement angles increase by 15.71°.This emphasizes the technology's suitability for local mining design,which lays the groundwork for resource development,disaster prevention,and ecological protection in analogous contexts.

关键词： Time-series InSAR Surface deformation Subsurface mining Mining subsidence