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Journal of Hydrodynamics 2020年第3期32卷 623-628页

作者： Cong Trieu Tran xin-ping Long Bin Ji Chaoqun liu State Key Laboratory of Water Resources and Hydropower Engineering Science Wuhan UniversityWuhan 430072China School of Power and Mechanical Engineering Wuhan UniversityWuhan 430072China Facullty of Hydraulic Engineering National University of Civil Engineering 55 GiaiPhongHanoiVietnam Department of Mathematics University of Texas at ArlingtonArlington 76019USA

The turbulent flow in the draft tube of a Francis turbine is very complicated while working under off-design conditions. Although the off-design conditions were widely studied, the vortex core line in the draft tube of a Francis turbine with splitter blades is not well understood, especially the vortex rope property. This letter presents a prediction of the behavior of the vortex rope in the draft tube of the Francis-99 turbine obtained by the computational fluid dynamics (CFD), where the liutex/Rortex method, as the most recent vortex definition, is applied to analyze the periodical precession of the vortex rope in the draft tube cone. The advantage of this liutex/Rortex method is shown by its enhanced ability to represent the vortex rope structurewith the vortex-core lines. Furthermore, since it seems to be very hard to define a sharp boundary surface for the whole vortex structure, it is advantageousfocusing only on the vortex core line,by which different vortex structures can be clearly differentiated. The evolution of the vortex core and the process of the vortex breakdown in the draft tube are revealed, which might help to comprehend the development of the turbulent flow in the draft tube.

关键词： Cavitating vortex rope Francis turbine liutex/Rortex method off-design condition vortex core line

Assessment of hepatic VX_2 tumors with combined percutaneous transhepatic lymphosonography and contrast-enhanced ultrasonographic imaging

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World Journal of Gastroenterology 2008年第24期14卷 3908-3913页

作者： Cun liu ping Liang Yang Wang Pei Zhou xin Li Shao-ping liu Department of Ultrasound QiluHospital Shandong University 107 Wenhua West Road Jinan250012 Shandong Province China Department of Ultrasound Chinese PLA General Hospital 28Fuxing Road Beijing 100853 China

AIM： To evaluate the feasibility and efficacy of percutaneous transhepatic lymphosonography （PTL） as a novel method for the detection of tumor lymphangiogenesis in hepatic VX2 of rabbits and to evaluate combined PTL and routine contrast-enhanced ultrasonographic imaging for the diagnosis of liver cancer. METHODS： Ten rabbits with VX2 tumor were included in this study. SonoVue （0.1 mL/kg） was injected into each rabbit via an ear vein for contrast-enhanced ultrasonographic imaging, and 0.5 mL SonoVue was injected into the normal liver parenchyma near the VX2 tumor for PTL. Images and/or movie clips were stored for further analysis. RESULTS： UItrasonographic imaging showed VX2 tumors ranging 5-19 mm in the liver of rabbits. The VX2 tumor was hyperechoic and hypoechoic to liver parenchyma at the early and later phase, respectively. The hepatic lymph vessels were visualized immediately after injection of contrast medium and continuously vi- sualized with SonoVue during PTL. The boundaries of VX2 tumors were hyperechoic to liver parenchyma and the tumors. There was a significant difference in the values for the boundaries of VX2 tumors after injection compared with the liver normal parenchyma and the tumor parenchyma during ***： PTL is a novel method for the detection of tumor lymphangiogenesis in hepatic VX2 of rabbits. Combined PTL and contrast-enhanced ultrasonographic imaging can improve the diagnosis of liver cancer.

关键词： Percutaneous transhepatic lymphosonography Ultrasound Contrast-enhanced ultrasonographicimaging Ultrasound contrast media VX2 tumor

Deflagration to detonation transition in weakly confined conditions for a type of potentially novel green primary explosive:Al/Fe_(2)O_(3)/RDX hybrid nanocomposites

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Defence Technology（防务技术） 2023年第4期22卷 28-36页

作者： Qing-ping Luo xin-ping Long Fu-de Nie Gui-xiang liu Chao Wu State Key Laboratory of Environmental-friendly Energy Materials Southwest University of Science and TechnologyMianyang621010China Institute of Chemical Materials Chinese Academy of Engineering PhysicsMianyang621900China

The properties of the combustion and deflagration to detonation transition(DDT)of Al/Fe_(2)O_(3)/RDX hybrid nanocomposites,a type of potentially novel lead-free primary explosives,were tested in weakly confined conditions,and the interaction of Al/Fe_(2)O_(3)nanothermite and RDX in the DDT process was studied in *** show that the amount of the Al/Fe_(2)O_(3)nanothermite has a great effect on the DDT properties of Al/Fe_(2)O_(3)/RDX *** addition of Al/Fe_(2)O_(3)nanothermite to RDX apparently improves the firing properties of RDX.A small amount of Al/Fe_(2)O_(3)nanothermite greatly increases the initial combustion velocity of Al/Fe_(2)O_(3)/RDX nanocomposites,accelerating their DDT *** the contents of Al/Fe_(2)O_(3)nanothermite are less than 20 wt%,the DDT mechanisms of Al/Fe_(2)O_(3)/RDX nanocomposites follow the distinct abrupt mode,and are consistent with that of RDX,though their DDT processes are *** RDX added into the Al/Fe_(2)O_(3)nanothermite increases the latter's peak combustion velocity and makes it generate the DDT when the RDX content is at least 10 wt%.RDX plays a key role in the shock compressive combustion,the formation and the properties of the DDT in the flame propagation of *** with RDX,the fast DDT of Al/Fe_(2)O_(3)/RDX nanocomposites could be obtained by adjusting the chemical constituents of nanocomposites.

关键词： Green primary explosives Al/Fe_(2)O_(3)/RDX nanocomposites Deflagration to detonation transition Mechanism

中药调节自噬相关信号通路改善激素性股骨头坏死的研究进展

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中医康复 2025年第1期2卷 60-65页

作者：马平齐鑫陈欣胡紫阳刘建军甘肃中医药大学附属医院甘肃兰州730000 甘肃中医药大学甘肃兰州730000

激素性股骨头坏死(steroid-induced avascular necrosis of the femoral head,SANFH)是一类临床骨科系统常见病与多发病,究其原因是激素的不合理使用造成股骨头缺血缺氧,而最终发展为股骨头坏死。目前来说,对SANFH的治疗尚无临床特效药... 详细信息

激素性股骨头坏死(steroid-induced avascular necrosis of the femoral head,SANFH)是一类临床骨科系统常见病与多发病,究其原因是激素的不合理使用造成股骨头缺血缺氧,而最终发展为股骨头坏死。目前来说,对SANFH的治疗尚无临床特效药物,但随着研究手段的进步,已发现自噬在该病的致病过程中扮演重要角色,且已明确部分信号通路能够对自噬产生影响。现阶段,中药防治SANFH的研究备受关注,但其作用机制尚不清楚。本文通过查阅相关国内外文献,就自噬(成骨细胞、破骨细胞、线粒体等)与SANFH的发病关系及中药(如黄芪多糖、葛根素、柚皮苷、川芎嗪、淫羊藿苷等中药单体及化合物,以及桂枝芍药知母汤、右归饮、健骨散、骨痹通消方、活血通络汤等中药复方)调节自噬相关信号通路从而改善SANFH进行概述,以期为拓展SANFH的治疗措施及明确中药应用价值提供参考。

关键词：激素性股骨头坏死自噬中药单体复方信号通路凋亡成骨细胞破骨细胞

Balance energy-efficient and real-time with reliable communication protocol for wireless sensor network

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The Journal of China Universities of Posts and Telecommunications 2013年第1期20卷 37-46页

作者： liu Zhi-xin DAI Li-li MA Kai GUAN xin-ping Institute of Electrical Engineering Yanshan University School of Electronic Information and Electrical Engineering Shanghai Jiao Tong University

In many wireless sensor network applications, it should be considered that how to trade off the inherent conflict between energy efficient communication and desired quality of service such as real-time and reliability of transportation. In this paper, a novel routing protocols named balance energy-efficient and real-time with reliable communication （BERR） for wireless sensor networks （WSNs） are proposed, which considers the joint performances of real-time, energy efficiency and reliability. In BERR, a node, which is preparing to transmit data packets to sink node, estimates the energy cost, hop count value to sink node and reliability using local information gained from neighbor nodes. BERR considers not only each sender＇ energy level but also that of its neighbor nodes, so that the better energy conditions a node has, the more probability it will be to be chosen as the next relay node. To enhance real-time delivery, it will choose the node with smaller hop count value to sink node as the possible relay candidate. To improve reliability, it adopts retransmission mechanism. Simulation results show that BERR has better performances in term of energy consumption, network lifetime, reliability and small transmitting delay.

关键词： wireless sensor network tradeoff energy efficiency real-time reliable communication retransmission lifetime of network

BmSLC7A5 is essential for silk protein synthesis and larval development in Bombyx mori

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Insect Science 2024年第5期31卷 1425-1439页

作者： xin Tang Huawei liu xin Wang Li Chang Qingsong liu Qingyou Xia ping Zhao Integrative Science Center of Germplasm Creation in Western China(CHONGQING)Science City Biological Science Research CenterSouthwest UniversityChongqingChina Chongqing Key Laboratory of Chinese Medicine&Health Science Chongqing Academy of Chinese Materia MedicaChongqing College of Traditional Chinese MedicineChongqingChina Key Laboratory for Germplasm Creation in Upper Reaches of the Yangtze River Ministry of Agriculture and Rural AffairsChongqingChina

Insects produce silk to form cocoons,nests,and webs,which are important for their survival and ***,little is known about the molecular mecha-nism of silk protein synthesis at the translation *** solute carrier family 7(SLC7)genes are involved in activating the target of rapamycin complex 1(TORC1)signaling pathway and protein translation process,but the physiological roles of SLC7 genes in silk-producing insects have not been ***,we found that amino acid signaling regulates silk protein synthesis and larval development via the L-type amino acid trans-porter 1(LAT1;also known as SLC7A5)in Bombyx mori.A total of 12 SLC7 homologs were identified in the silkworm genome,among which BmSLC7A5 was found to be a silk gland-enriched gene and may be involved in leucine *** analy-sis indicated that SLC7A5 displays high homology and a close phylogenetic relationship in silk-producing ***,we found that leucine treatment significantly in-creased silk protein synthesis by improving the transcription and protein levels of silk ***,systemic and silk gland-specific knockout of BmSLC7A5 led to de-creased silk protein synthesis by inhibiting TORC1 signaling,and somatic mutation also resulted in arrested development from the 5th instar to the early pupal ***,our study reveals that BmSLC7A5 is involved in regulating silk protein synthesis and larval development by affecting the TORC1 signaling pathway,which provides a new strategy and target for improving silk yield.

关键词： amino acid signaling Bombyx mori larval development SLC7A5 silk pro-tein synthesis TORC1 signaling pathway

Surface effect induced phase transformation by Mn removal during annealing and its textures in cold-rolled high manganese transformation-induced plasticity steel

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Journal of Iron and Steel Research International 2022年第3期29卷 494-502页

作者： Li-ying liu ping Yang Dan-dan Ma xin-fu Gu School of Materials Science and Engineering University of Science and Technology BeijingBeijing100083China

The surface effect induced transformation texture during vacuum annealing of cold-rolled high manganese transformation-induced plasticity(TRIP)steels was *** to Mn removal occurring at the surface layer,γ→δdiffusional phase transformation leads to the formation of hard pancake-shaped ferrite grains due to solution strengthening at the surface and the centre layer remains as austenite+martensite after *** the case of slow heating,{112}/{111}textures for the surface ferrite were strengthened with the increase in temperature and holding time,indicating an inheritance of rolling *** increasing the heating rate of annealing,the rotated cube texture was developed in surface *** kind of multiphase sandwich structure with hard ferrite surface layer and tough austenite dominant centre can increase tensile strength and should also improve deep drawing properties,therefore providing new possibility of controlling properties for the application of high manganese TRIP steel.

关键词： High manganese transformation-induced plasticity steel Surface effect Texture Microstructure Vacuum annealing

Three-Dimensional Collapse Analysis for a Shallow Cavity in Layered Strata Based on Upper Bound Theorem

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Computer Modeling in Engineering & Sciences 2020年第7期124卷 375-391页

作者： Hongtao Wang ping liu Lige Wang Chi liu xin Zhang Luyao liu School of Civil Engineering Shandong Jianzhu UniversityJinanChina Key Laboratory of Building Structural Retrofitting and Underground Space Engineering(Shandong Jianzhu University) Ministry of EducationJinanChina Department of Chemical and Biological Engineering University of SheffieldSheffieldUK State Key Laboratory of Geomechanics and Geotechnical Engineering Institute of Rock and Soil MechanicsChinese Academy of SciencesWuhanChina Jinan Rail Transit Group Co. Ltd.JinanChina

Layered rock strata are observed to be common during the excavation of tunnels or cavities,and may significantly affect the deformation and failure characteristics of surrounding rock masses due to various complex forms and mechanical *** this paper,we propose a three-dimensional axisymmetric velocity field for roof collapse of shallow cavities in multi rock layers,by considering the influences of roof cross-section shapes,supporting pressure,ground overload,*** internal energy dissipation rate and work rates of external forces corresponding to the velocity field are computed by employing the Hoek-Brown strength criterion and its associated flow ***,the equations of the collapse surfaces and the corresponding weight of collapsing rock masses are derived on the basis of upper bound ***,we validate the proposed method by comparing the results of numerical calculations and existing research *** change laws of the collapse range under varying parameters are obtained for the presence of rectangular and spherical *** also find that the three-dimensional mechanism is relatively safer for engineering designing actually,compared with the traditional two-dimensional *** these conclusions may provide workable guidelines for the support design of shallow cavities in layered rock strata practically.

关键词： Shallow cavity three-dimensional collapse layered rock strata upper

Polymorphic Transition of Pre-oriented Polybutene-1 under Tensile Deformation:In Situ FTIR Study

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Chinese Journal of Polymer Science 2020年第8期38卷 888-897,I0008页

作者： Zhen Zhang xin Chen Chuang Zhang Chun-Tai liu Zhen Wang Yan-ping liu National Engineering Research Center for Advanced Polymer Processing Technology Key Laboratory of Materials Processing and Mold(Zhengzhou University)Ministry of EducationZhengzhou UniversityZhengzhou 450002China National Center for International Research of Micro-nano Molding Technology&Key Laboratory for Micro Molding Technology of Henan Province Zhengzhou UniversityZhengzhou 450002China

Deformation-induced phase transition of FormⅡto FormⅠin polybutene-1(PB-1)has been investigated by time-resolved Fourier transform infrared(FTIR)spectroscopy over a wide temperature range from 25℃to 105℃.The initial film sample containing orientated lamellae is prepared by pre-stretching of PB-1 melt followed by *** is to realize a homogeneity of subsequent deformation at the mesoscale of lamellar stacks by avoiding large-scale *** deformation induced phase transition is recognized to occur with two stages:first,FormⅡundergoes the lamellar fragmentation,slipping or local melting after yielding to activate its transition to FormⅠ,which may be realized by releasing the restrictions on chains translational movements in crystalline phase;second,the phase transition proceeds with a continuous dissipation of external work and determines the tensile mechanical response of *** quantify the relationship between crystalline transition of FormⅡto FormⅠand external tensile field,a simple kinetic equation is well established based on FTIR *** equation can describe not only the dependence of crystal transitional degree on applied specific work,but also the retardation effect of elevating temperature on phase transition.

关键词： Polybutene-1 Tensile deformation FTIR Crystalline transition External work

The extremely cold 2009-2010 winter and its relationship with the Arctic oscillation

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Frontiers of physics 2013年第5期8卷 590-603页

作者： xin-Yu Wen Yong-Yun Hu Ji-ping liu Laboratory for Climate and Ocean-Atmosphere Studies Department of Atmospheric and Oceanic Sciences School of Physics Peking University Beijing 100871 China 2Department of Atmospheric and Environmental Sciences University at Albany State University of New York NY 12222 USA

The Northern-Hemisphere high-latitude continents experienced extremely cold weathers in winter 2009 2010. In the present paper, we show that the cold winter was associated with the activity of tile Arctic oscillation （AO）, which demonstrated the strongest negative polarity over the past six decades and persisted from December, 2009 to March, 2010. It is found that variations of the surface AO was closely linked to stratospheric polar vortex anomalies, and that the surface AO phases followed downward propagation of stratospheric Northern-Hemisphere Annular mode （NAM） anomalies during the winter. The case of 2009-2010 winter provides us with a typical example that anomalous stratospheric signals can be used to improve skills of long-range weather forecast and intra-seasonal climate prediction in winter time. We also show that the E1 Nifio event, which started developing from May 2009, might contribute the formation of exceptionally negative and persistent AO and stratospheric NAM, particularly over North Pacific and North America.

关键词： Arctic oscillation Northern-Hemisphere Annular mode (NAM) stratosphere planetarywaves weather forecast