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Chinese Journal of Aeronautics 2024年第6期37卷 20-37页

作者： Zhiyu LI kaiyuan zhang Zhigang LI Jun LI Institute of Turbomachinery Xi’an Jiaotong UniversityXi’an 710049China

The mid-passage gap is an inevitable structure in a vane passage due to turbine vanes being manufactured *** coolant from this gap is able to prevent hot mainstream ingression and provide cooling protection for the endwall.A novel idea of enlarging the endwall’s coverage area and reducing the endwall’s thermal load by applying the mid-passage gap with variable surface angles is carried out in this *** endwall’s aerothermal and film cooling performances under four mid-passage gap modes at three typical mass flow ratio conditions are numerically *** indicate that under the traditional mid-passage mode,the coolant flows into the mainstream with a perpendicular incidence angle and can’t stick to the ***,cooling failure occurs,and the endwall’s thermal load is badly *** film cooling level at the suction-side endwall is improved when applying the mid-passage gap of a 45surface angle due to the secondary vortex being *** addition,when applying the mid-passage gap of a 135surface angle,the horseshoe vortex is pushed away,and the coverage area at the pressure-side endwall is enlarged *** best film cooling performance is achieved when the upstream surface angle is 135and the downstream surface angle is 45due to the adiabatic film cooling effectiveness being increased at both the pressure-and suction-side *** the mass flow ratio is 1.5%,the coverage area is enlarged by 43%,and the area-averaged adiabatic film cooling effectiveness is increased by 37%,when compared with those under the traditional mid-passage mode.

关键词： Film cooling Heat transfer Surface angle Mid-passagegap Turbinevane endwall

A polarized^(3)He system based on metastability-exchange optical pumping

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Science China(Physics,Mechanics & Astronomy) 2024年第7期67卷 72-81页

作者： Yuting Wang Liangyong Wu kaiyuan zhang Mei Peng Siyu Chen Haiyang Yan State Key Laboratory of Nuclear Physics and Technology School of PhysicsPeking UniversityBeijing 100871China Institute of Nuclear Physics and Chemistry China Academy of Engineering PhysicsMianyang 621900China Key Laboratory of Nuclear Physics and Ion-beam Application(MOE) Fudan UniversityShanghai 200433China Key Laboratory of Neutron Physics Institute of Nuclear Physics and ChemistryChina Academy of Engineering PhysicsMianyang 621900China

Hyperpolarized^(3)He nuclei have emerged as a significantly important approach in quantum precision measurement techniques,with extensive applications in fundamental physics,magnetometry,metrology,and *** this study,we report on the design and implementation of a^(3)He polarization system at the China Mianyang Research Reactor(CMRR),utilizing the metastabilityexchange optical pumping(MEOP)*** employed a Merritt coil system consisting of four square coils to furnish a uniform holding *** deployed a 2 W fiber laser to pump the metastable^(3)He atoms and conducted free induction decay(FID)detection of the polarized^(3)He nuclei using both pickup coil and optical *** the optical method,we used a50 m W linearly polarized distributed Bragg reflector(DBR)laser as the *** applied transverse light absorption polarimetry to measure the absolute nuclear polarization of the ground-state^(3)*** have developed cell fabrication capabilities at the CMRR,and cells at various pressures ranging from 100 to 1000 Pa have been fabricated and *** a typical borosilicate cell with 100 Pa pressure,the absolute polarization is measured as Pn≈70%,and the transverse relaxation time is estimated as T2≈0.5 ***,we constructed a few aluminosilicate cells,each carefully filled with pure^(3)He at a pressure of 100 ***,we conducted a comprehensive evaluation of their performance in the context of MEOP.

关键词： metastability exchange optical pumping polarized^(3)He magnetic resonance

燃烧室百叶与双排孔冷气对透平端壁冷却性能影响研究

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西安交通大学学报 2024年第6期58卷 65-76页

作者：张垲垣栗智宇李志刚李军西安交通大学能源与动力工程学院西安710049

针对燃烧室与透平冷气掺混导致实际二次流发展及端壁冷却性能偏离设计值的问题,综合考虑燃烧室百叶冷气尾迹与双排孔射流,数值研究了多源冷气射流在燃烧室与透平交界区的掺混机制,分析了其对透平静叶端壁气膜冷却与流动特性的影响规律... 详细信息

针对燃烧室与透平冷气掺混导致实际二次流发展及端壁冷却性能偏离设计值的问题,综合考虑燃烧室百叶冷气尾迹与双排孔射流,数值研究了多源冷气射流在燃烧室与透平交界区的掺混机制,分析了其对透平静叶端壁气膜冷却与流动特性的影响规律。研究结果表明:空腔涡卷吸大部分百叶冷气,并跨越双排孔冷气向下游发展,马蹄涡卷吸限制大部分双排孔冷气,并向空腔涡外侧发展;当双排孔冷气吹风比M_h=0.5,1.0较小时,马蹄涡导致冷气形成楔形高冷效区域,空腔涡的附着侧和分离侧分别产生了高、低冷效区,随着百叶冷气吹风比M_l的增加,空腔涡强度显著降低,导致位于楔形中心的分离侧冷却效率有所提升;当双排孔冷气吹风比M_h为1.5时,双排孔冷气部分跨越马蹄涡,静叶端壁可实现完全冷气覆盖,此时百叶冷气吹风比M_l从0.5增加到1.5,静叶端壁平均冷却效率可从0.4提升到0.63。该研究为考虑燃烧室与透平交界区实际流动掺混情况的静叶端壁冷却结构与布局设计提供理论基础。

关键词：透平静叶端壁燃烧室百叶冷气双排孔射流气膜冷却

Recent Progress on Halo Nuclei in Relativistic Density Functional Theory

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原子核物理评论 2024年第1期41卷 191-199页

作者： zhang kaiyuan PAN Cong CHEN Siyu LUO Qingjin WU Keyan XIANG Yifeng Institute of Nuclear Physics and Chemistry China Academy of Engineering PhysicsMianyang 621900SichuanChina Department of Physics Anhui Normal UniversityWuhu 241000AnhuiChina

Since the discovery of the halo nucleus ^(11)Li in 1985,halo phenomena in exotic nuclei have always been an important frontier in nuclear physics *** relativistic density functional theory has achieved great success inthestudyofhalonucleg,theself-consistent description ofhalonucleusLiandthe microscopic predic tion of deformed halo *** paper introduces some recent progresses based on the deformed relativistic Hartree-Bogoliubov theory in continuum(DRHBc)and the triaxial relativistic Hartree-Bogoliubov theory in continum(TRHBc).A microscopic and self-consistent description of the deformed halo nucleus ^(37)Mg,including its small one-neutron separation energy,large root-mean-square radius,diffuse density distribution,and p-wave components for the halo neutron,has been achieved by the DRHBc *** DRHBc theory has also predicted a deformed neutron halo and the collapse of the N=28 shll closureintherecently discovered isotope ^(39)Na The TRHBc theory has been newly developed and applied to the aluminum isotopic *** heaviest odd-odd ^(42)AI has been predicted as a triaxial halo nucleus with a novel shape decoupling between its core and halo at the triaxial level.

关键词： halo phenomena relativistic density functional theory^(37)Mg ^(39)Na^(42)A1

500 kV输电线路劣化瓷绝缘子非线性发热特性的红外分析

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高压电器 2024年第1期60卷 33-40页

作者：裴少通马子儒刘云鹏张凯元杨家骏华北电力大学河北省分布式储能与微网重点实验室河北保定071003 华北电力大学河北省输变电设备安全防御重点实验室河北保定071003

高压输电线路绝缘子串中的劣化件会威胁电网安全。为了研究劣化瓷绝缘子的红外发热特性,设置了一系列实验,研究了劣化绝缘子的电阻、沿串位置和环境相对湿度对红外检测的影响。并对含有两片劣化绝缘子的绝缘子串进行了附加实验,以研究... 详细信息

高压输电线路绝缘子串中的劣化件会威胁电网安全。为了研究劣化瓷绝缘子的红外发热特性,设置了一系列实验,研究了劣化绝缘子的电阻、沿串位置和环境相对湿度对红外检测的影响。并对含有两片劣化绝缘子的绝缘子串进行了附加实验,以研究了正常绝缘子和低值绝缘子之间不同的发热现象。利用有限元分析仿真进一步分析了红外图像中钢帽的发热机理。实验和仿真结果表明:劣化绝缘子的温升与阻值呈非线性关系,当电阻为30 MΩ时温升最大;绝缘子串两端的劣化易被检测;相对湿度过高可能会导致误检;正常绝缘子的发热区域是钢帽的下部,瓷件的温度上升1.2℃左右,而对于劣化绝缘子,沿钢帽的温升分布均匀,瓷件的温度与实验前基本一致。相关研究结果为劣化绝缘子的红外检测提供了参考依据。

关键词：红外热成像劣化绝缘子发热相对湿度有限元法

添加牛粪堆肥对盆栽菊花生长及抑菌效果的影响

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北方园艺 2024年第13期 42-48页

作者：岳莉然张楷苑刘铭宇东北林业大学园林学院黑龙江哈尔滨150006

以3个菊花品种(‘辉煌’‘波尔多红’‘黄芙蓉’)为试材,采用添加不同比例(栽培基质与牛粪堆肥的体积比分别为1∶1、3∶1、5∶1)的牛粪堆肥进行基质复配的方法开展育苗试验,研究添加不同体积牛粪堆肥对栽培基质的理化性质以及盆栽菊花... 详细信息

以3个菊花品种(‘辉煌’‘波尔多红’‘黄芙蓉’)为试材,采用添加不同比例(栽培基质与牛粪堆肥的体积比分别为1∶1、3∶1、5∶1)的牛粪堆肥进行基质复配的方法开展育苗试验,研究添加不同体积牛粪堆肥对栽培基质的理化性质以及盆栽菊花的形态、生理指标以及抑菌效果的影响,以期降低盆栽菊花染病机率,提高其观赏性。结果表明:随牛粪堆肥占比增加,基质容重增加,碱解氮、有效磷和速效钾含量增加,pH上升,孔隙度降低,EC值变化不明显。基质中添加牛粪堆肥可以显著促进盆栽菊花株高的伸长、花茎增粗、冠幅增大、叶片生长。3种盆栽菊花在对照中病情指数最高,可溶性蛋白质含量最低。处理盆栽菊花的成活率均为100%。在Y1处理下‘辉煌’长势最好,‘波尔多红’和‘黄芙蓉’在Y3处理时长势最好。‘辉煌’在Y1、Y2处理中病情指数最低,‘波尔多红’和‘黄芙蓉’在Y3处理中病情指数最低,因此在基质中适量添加牛粪堆肥能够促进盆栽菊花生长,降低其患病机率。

关键词：基质牛粪堆肥盆栽菊花抑菌

三峡库区万县复向斜构造特征及其与地质灾害分布关系

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三峡大学学报（自然科学版） 2024年第1期46卷 49-56页

作者：王岚许晓亮周准张凯元三峡库区地质灾害教育部重点实验室湖北宜昌443002 三峡大学土木与建筑学院湖北宜昌443002

万县复向斜位于川东褶皱带与大巴山-大洪山构造带复合部位,前人侧重于基础地质及页燃气勘探相关领域的研究,对于万县向斜局部构造特征与地质灾害的内在关系的研究尚少.本文在野外地质调查研究的基础上,利用部分滑坡的勘察资料,采用构造... 详细信息

万县复向斜位于川东褶皱带与大巴山-大洪山构造带复合部位,前人侧重于基础地质及页燃气勘探相关领域的研究,对于万县向斜局部构造特征与地质灾害的内在关系的研究尚少.本文在野外地质调查研究的基础上,利用部分滑坡的勘察资料,采用构造地质与工程地质的分析方法,深入研究了万县向斜局部构造对该区域地质灾害的控制作用,将万县向斜内部分为:西部NE向构造叠加构造区域;中部故陵向斜轴迹NE向区域;东部故陵向斜轴迹近EW向区域(也是故陵向斜翘倾消亡部位).与局部构造相对应,将内部地质灾害同样划分为西部、中部和东部3个区域进行研究,得出如下结论:西部地质灾害发育规模小,主要集中于局部纵谷地段;中部地质灾害集中于长江北岸,岩层陡缓倾角转化带的存在对地质灾害的规模起到了控制作用;东部地质灾害集中于长江南岸,除岩层陡缓倾角转化带的存在对地质灾害的规模起到了主要控制作用以外,斜坡坡长和岩层产状中陡倾的特点对地质灾害的发生同样具有重要的控制作用.本次研究阐明了万县复向斜内部构造特征与该地区地质灾害的内在联系,对研究区域内地质灾害的预测预报提供了一定的参考和依据.

关键词：万县向斜地质灾害滑坡局部构造

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东北少数民族传统服饰非遗文化传承与保护

丝网印刷 2024年第17期 38-40页

作者：李际张开源吉林艺术学院

东北地区少数民族的历史、艺术和传统服饰非遗文化,是中华传统文化艺术的重要组成部分。挖掘其传统服饰非遗文化、研究其传统服饰非遗文化传承与保护,对促进民族团结、推动传统艺术的传承与创新具有重要意义。

关键词：东北少数民族传统服饰非遗文化传承与保护

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高纤维食物对黑线仓鼠哺乳期能量收支的影响

兽类学报 2024年第4期44卷 436-448页

作者：赵真张开元杨瑞曹静赵志军温州大学生命与环境科学学院浙江省水环境与海洋生物资源保护重点实验室温州325035

繁殖期是小型哺乳动物最重要的生活史阶段之一,哺乳期是母体能量需求最高的时期。为满足后代的能量需求,母体通常显著增加能量摄入,达到最大持续能量摄入(maximal sustained energy intake,mSusEI)。动物消化道形态和消化机能具有可塑性... 详细信息

繁殖期是小型哺乳动物最重要的生活史阶段之一,哺乳期是母体能量需求最高的时期。为满足后代的能量需求,母体通常显著增加能量摄入,达到最大持续能量摄入(maximal sustained energy intake,mSusEI)。动物消化道形态和消化机能具有可塑性,然而消化系统是否限制了哺乳期mSusEI,尚不确定。本文以高纤维食物饲喂哺乳期黑线仓鼠(Cricetulus barabensis),通过测定体重、摄食量、摄入能和消化率、代谢率、泌乳能量输出,以及消化系统重量和消化酶活性等,分析哺育不同胎仔数的母体能量摄入与繁殖输出,比较在不同能量需求的条件下,消化酶活性的变化。结果发现,黑线仓鼠哺乳期的能量收支与其哺育后代的数量有关,哺乳期mSusEI未受高纤维食物的显著影响。饲喂高纤维食物未影响摄入能,但显著降低了消化能和消化率,母乳能量输出也显著减少,不能满足后代幼体的能量需求,导致幼体发育变缓。高纤维食物使胃、小肠、大肠和盲肠重量显著增加,小肠淀粉酶、麦芽糖酶和氨基肽酶活性显著增强,但未受胎仔数的显著影响。结果表明,哺乳期mSusEI的瓶颈可能来自消化系统,支持中心限制假说。由于“中心限制”的存在,食物中纤维素含量升高可能会降低动物繁殖价值。

关键词：能量代谢高纤维食物繁殖输出胎仔数黑线仓鼠

Physical model test and numerical simulation on the failure mechanism of the roadway in layered soft rocks

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International Journal of Mining Science and Technology 2021年第2期31卷 291-302页

作者： Xiaoming Sun Chengwei Zhao Yong zhang Feng Chen Shangkun zhang kaiyuan zhang State Key Laboratory for GeoMechanics and Deep Underground Engineering China University of Mining and Technology-BeijingBeijing 100083China School of Mechanics and Civil Engineering China University of Mining and Technology-BeijingBeijing 100083China School of Civil Engineering Nanyang Institute of TechnologyNanyang 473004China

To explore the failure mechanism of roadway in layered soft rocks,a physical model with the physically finite elemental slab assemblage(PFESA)method was *** thermography and a video camera were employed to capture thermal responses and *** model results showed that layered soft roadway suffered from large deformation.A three-dimensional distinct element code(3 DEC)model with tetrahedral blocks was built to capture the characteristics of roadway deformation,stress,and *** results showed two failure patterns,layer bending fracture and layer slipping after *** layer bending fracture occurred at positions where the normal direction of layers pointed to the inside of the roadway and the layer slipping occurred in the *** schemes were proposed to investigate the effects of layered soft *** results showed that the deformation of ribs was obviously larger than that of the roof and floor when the roadway passed through three types of *** the roadway was completely in a coal seam,the change of deformation in ribs was not obvious,while the deformation in the roof and floor increased *** results can provide guidance for excavation and support design of roadways in layered soft rocks.

关键词： Failure mechanism Physical model test 3DEC Layered soft rocks Large deformation