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High-strength aluminum alloys hollow billet prepared by two-phase zone continuous casting

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China Foundry 2022年第3期19卷 253-262页

作者： Yao-hua Yang xue-feng liu Wang-zhang Chen Beijing Advanced Innovation Center for Materials Genome Engineering University of Science and Technology BeijingBeijing 100083China Beijing Laboratory of Metallic Materials and Processing for Modern Transportation University of Science and Technology BeijingBeijing 100083China Key Laboratory for Advanced Materials Processing of Ministry of Education University of Science and Technology BeijingBeijing 100083China Shunde Graduate School University of Science and Technology BeijingFoshan 528399GuangdongChina

The two-phase zone continuous casting(TZCC)technique was used to continuously cast high-strength aluminum alloy hollow billets,and a verified 3D model of TZCC was used to simulate the flow and temperature fields at casting speeds of 2-6 mm·min^(-1).Hollow billets under the same conditions were prepared,and their macro/microstructures were analyzed by an optical microscope and a scanning electron *** the TZCC process,a circular fluid flow appears in front of the mushy zone,and the induction heated stepped mold and convective heat transfer result in a curved solidification front with depressed region near the inner wall and a vertical temperature *** deflection of the solidification front decreases and the average cooling rate in the mushy zone increases with increasing casting *** results for a 2D12 alloy show that hot tearing periodically appears in the hollow billet accompanied by macrosegregation near the inner wall at casting speeds of 2 and 4 mm·min^(-1),while macroscopic defects of hot tearing and macrosegregation weaken and the average size of columnar crystals in the hollow billets decreases with further increasing casting speed.2D12 aluminum alloy hollow billets with no macroscopic defects,the finest columnar crystals,and excellent mechanical properties were prepared by TZCC at a casting speed of 6 mm·min^(-1),which is beneficial for the further plastic forming process.

关键词： two-phase zone continuous casting high-strength aluminum alloy hollow billet fluid flow heat transfer columnar crystals

Plasmonic-photonic cavity for high-efficiency single-photon blockade

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Science China(Physics,Mechanics & Astronomy) 2021年第7期64卷 98-107页

作者： Yu-Wei Lu Jing-Feng liu Zeyang Liao xue-hua Wang State Key Laboratory of Optoelectronic Materials and Technologies School of PhysicsSun Yat-sen UniversityGuangzhou510275China College of Electronic Engineering South China Agricultural UniversityGuangzhou510642China

The generation and manipulation of single photons are crucial in advanced quantum technologies, such as quantum communication and quantum computation devices. High-purity single photons can be generated from classical light using the single-photon blockade(1 PB). However, the efficiency and purity are exclusive in 1 PB, which hinders its practical applications. Here, we show that the resonantly coupled plasmonic-photonic cavity can boost the efficiency of single-photon generation by more than three orders of magnitude compared with that of all-dielectric microcavity. This significant improvement is attributed to two new mechanisms of atom-microcavity coupling after introducing the plasmonic cavity: the formation of a quasi-bound state and the transition to the nonreciprocal regime, due to the destructive interference between the coupling pathways and the nonzero relative phase of the closed-loop coupling, respectively. The quasi-bound state has a relatively small decaying, while its effective coupling strength is significantly enhanced. Suppressing the dissipative component of the effective atom-microcavity coupling in the nonreciprocal regime can further improve single-photon performance, particularly without temporal oscillations. Our study demonstrates the possibility of enhancing the intrinsically low efficiency of 1 PB in low excitation regime, and unveils the novel light-matter interaction in hybrid cavities.

关键词： single-photon blockade atom-photon quasi-bound state plasmonic-photonic cavity

Classification,biosynthesis,and biological functions of triterpene esters in plants

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Plant Communications 2024年第4期5卷 67-93页

作者： Jia liu xue Yin Chengxi Kou Ramesha Thimmappa Xin hua Zheyong xue Key Laboratory of Saline-alkali Vegetation Ecology Restoration(Northeast Forestry University) Ministry of EducationHarbin 150040China Heilongjiang Key Laboratory of Plant Bioactive Substance Biosynthesis and Utilization Northeast Forestry UniversityHarbin 150040China Amity Institute of Genome Engineering Amity UniversityNoidaUP India 201313India State Key Laboratory for Quality Ensurance and Sustainable Use of Dao-di Herbs Beijing 100700P.R.China

Triterpene esters comprise a class of secondary metabolites that are synthesized by decorating triterpene skeletons with a series of oxidation,glycosylation,and acylation *** triterpene esters with important bioactivities have been isolated and identified,including those with applications in the pesticide,pharmaceutical,and cosmetic *** also play essential roles in plant defense against pests,dis-eases,physical damage(as part of the cuticle),and regulation of root ***,there has been no recent summary of the biosynthetic pathways and biological functions of plant triterpene ***,we classify triterpene esters intofive categories based on their skeletons andfind that C-3 oxidation may have a significant effect on triterpenoid *** acid and aromatic moieties are common li-gands present in triterpene *** further analyze triterpene ester synthesis-related acyltransferases(TEsACTs)in the triterpene biosynthetic *** an evolutionary classification of BAHD acyltrans-ferases(BAHD-ATs)and serine carboxypeptidase-like acyltransferases(SCPL-ATs)in Arabidopsis thaliana and Oryza sativa,we classify 18 TEsACTs with identified functions from 11 *** the triterpene-skel-eton-related TEsACTs belong to BAHD-AT clades IIIa and I,and the only identified TEsACT from the SCPL-AT family belongs to the CP-I *** comprehensive review of the biosynthetic pathways and bioactivities of triterpene esters provides a foundation for further study of their bioactivities and applica-tions in industry,agricultural production,and human health.

关键词： triterpene esters acyltransferases classification biosynthesis biological functions

A Normal Criterion about Two Families of Meromorphic Functions Concerning Shared Values

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Acta Mathematica Sinica,English Series 2013年第1期29卷 151-158页

作者： Xiao Jun liu San hua LI xue Cheng PANG Department of Mathematics University of Shanghai for Science and Technology Department of Mathematics East China Normal University

In this paper, we mainly discuss the normality of two families of functions concerning shared values and proved： Let F and G be two families of functions meromorphic on a domain D C C, a1, a2, a3, a4 be four distinct finite complex numbers. If G is normal, and for every f 9~, there exists g C G such that f（z） and g（z） share the values a1, a2, a3, a4, then F is normal on D.

关键词： Normal family shared values meromorphic functions

肝细胞癌的螺旋CT征象与病理及临床分期间关系研究

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实用放射学杂志 2002年第3期18卷 182-185页

作者：周志刚高剑波杨学华刘恒芳管生河南医科大学第一附属医院放射科河南医科大学第一附属医院放射科河南郑州450052

目的　探讨肝细胞癌的螺旋CT征象与病理及TNM分期间的关系。方法　分析螺旋CT平扫及增强检出的肝细胞癌 31例 ,其中 13例经CT导向下穿刺活检证实 ,18例经手术病理证实。结果　 ( 1)螺旋CT显示瘤体直径 >3cm、瘤体多发、边缘模糊不伴晕... 详细信息

目的　探讨肝细胞癌的螺旋CT征象与病理及TNM分期间的关系。方法　分析螺旋CT平扫及增强检出的肝细胞癌 31例 ,其中 13例经CT导向下穿刺活检证实 ,18例经手术病理证实。结果　 ( 1)螺旋CT显示瘤体直径 >3cm、瘤体多发、边缘模糊不伴晕圈征或中心伴坏死的病灶 ,其组织学分级均明显高于瘤体单发、边缘清晰伴晕圈征、中心不伴坏死者 (Ρ 3cm、多发、瘤体边缘模糊及瘤体中心伴有坏死者的组织学分化程度差且肿瘤侵袭力强 ;( 2 )螺旋CT对肝细胞肝癌的TNM分期能较准确地反映其侵袭力。

关键词：肝细胞癌体层摄影,X线计算机病理学 TNM分期

Phosphorylation at Ser28 stabilizes the Arabidopsis nitrate transporter NRT2.1 in response to nitrate limitation

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Journal of Integrative Plant Biology 2020年第6期62卷 865-876页

作者： xue Zou Meng-Yuan liu Wei-hua Wu Yang Wang State Key Laboratory of Plant Physiology and Biochemistry College of Biological SciencesChina Agricultural UniversityBeijing 100193China

Nitrate is one of the main inorganic nitrogen sources for *** absorption from soils is achieved through the combined activities of specific nitrate *** transporter 2.1(NRT2.1)is the major component of the root high-affinity nitrate transport system in Arabidopsis *** to date have mainly focused on transcriptional control of ***,we show that NRT2.1 protein stability is also regulated in response to nitrogen nutrition *** seedlings were transferred to nitrate-limited conditions,the apparent half-life of NRT2.1 in roots increased from 3 to 9 *** stabilization of NRT2.1 protein occurred rapidly,even prior to the transcriptional stimulation of ***,we revealed that phosphorylation at serine28(Ser28)of NRT2.1 is involved in regulating the stability of this *** of Ser28 by alanine resulted in unstable NRT2.1,and this loss-of-phosphorylation mutant(NRT2.1S28A)failed to complement the growth-restricted phenotype of the nrt2.1 mutant when a low concentration of nitrate was the sole nitrogen *** results demonstrate that phosphorylation at Ser28 is crucial for NRT2.1 protein stabilization and accumulation in response to nitrate limitation.

关键词： nitrate Arabidopsis stabilization

用“重置法”调整医院固定资产价值的方法研究

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中国卫生经济 2010年第12期29卷 84-86页

作者：徐小雪赵庆华刘国祥付文琦张歆黄卫东哈尔滨医科大学哈尔滨150086

针对当前很多医院固定资产管理存在价值不实的问题,本文提出利用"重置法"调整医院固定资产价值,还原其真实价值,并介绍了该方法的原理、操作过程及适用范围,便于医院进行固定资产价值评估,为医院的经营管理,投资决策提供准确的财务信息。

关键词：固定资产资产评估重置法

Combustion behavior and mechanism of molecular perovskite energetic material DAP-4-based composites with metal fuel Al

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Defence Technology（防务技术） 2023年第9期27卷 53-63页

作者： Peng Deng xue-yong Guo hua Fang Rui liu Peng-wan Chen State Key Laboratory of Explosion Science and Technology Beijing Institute of TechnologyBeijing100081PR China

Combined with the oxidizer anions and fuel cations,molecular perovskite energetic materials show a good *** this work,the combustion behavior and mechanism of metal fuel aluminium(Al)with molecular perovskite energetic material(H_(2)dabco)[NH4(ClO_(4))_(3)](DAP-4)as a high-energy oxidant was *** DAP-4 based composites with metal fuel Al were designed and fabricated by the different mass *** showed that DAP-4 exhibits a good oxygen-supplied capacity for enhancing the combustion performance of *** maximum combustion heat of DAP-4/Al-3 at the Al/O mass ratio of 38:62 is up to 10,412 J/g in the inert gas,which is higher than those of other ratios and the mixtures of other energetic materials and *** evolution of pressure output,pressurization rate,and flame temperature was monitored for DAP-4/Al with different mass *** DAP-4/Al/F were characterized by burning *** combustion reaction mechanism of metal fuel Al with DAP-4 as a high-energy oxidant was ***-4 was ignited firstly and released acid and oxidizing gases,which corroded Al_(2)O_(3)shells on Al particle surfaces and accelerated the combustion reaction with Al to release a lot of *** work offered a new idea that molecular perovskite energetic materials have great potential in the high-energy Al-based solid rocket propellants.

关键词： DAP-4 Metal fuel al Oxidant Combustion behavior Reaction mechanism

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艾滋病淋巴结肿大中医诊疗规程问卷调查研究

中国中医药信息杂志 2013年第3期20卷 11-13页

作者：吴巍黄世敬薛柳华潘菊华张颖陈宇霞张先慧中国中医科学院广安门医院北京100053

目的构建艾滋病淋巴结肿大中医临床诊疗操作规程。方法搜集和分析艾滋病淋巴结肿大中医诊疗相关国内外文献,经过专家组论证等方法,设计艾滋病淋巴结肿大中医临床诊疗操作规程问卷,并在全国范围内遴选专家,进行2轮问卷调查。结果通过2轮... 详细信息

目的构建艾滋病淋巴结肿大中医临床诊疗操作规程。方法搜集和分析艾滋病淋巴结肿大中医诊疗相关国内外文献,经过专家组论证等方法,设计艾滋病淋巴结肿大中医临床诊疗操作规程问卷,并在全国范围内遴选专家,进行2轮问卷调查。结果通过2轮专家问卷,初步建立了艾滋病淋巴结肿大中医临床诊断、治疗、调护及疗效评价规程。结论该规程明确了艾滋病淋巴结肿大病症含义与病因病机,突出了中医诊疗服务的标准化,同时体现宣教、随访及院内外连续性诊治的特点。

关键词：艾滋病淋巴结肿大中医诊疗规程问卷