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从“依形套式”到“循章衍法”:构形机理导引的历史城镇空间基因整体识别与活态传承

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中国名城 2024年第8期38卷 22-30页

作者：肖竞李和平蒋洁茹曹珂肖文斌重庆大学建筑城规学院重庆工商大学公共管理学院

针对历史城镇空间基因识别、保护实践“有形无态、重式轻法”问题,提出构形机理导引的空间基因整体识别与活态传承方法。以“原型特征+构形机理”的显隐属性和“城镇格局、地块形态、街巷形式、建筑风貌”四重空间尺度为历史城镇空间基... 详细信息

针对历史城镇空间基因识别、保护实践“有形无态、重式轻法”问题,提出构形机理导引的空间基因整体识别与活态传承方法。以“原型特征+构形机理”的显隐属性和“城镇格局、地块形态、街巷形式、建筑风貌”四重空间尺度为历史城镇空间基因要素解析框架,以“要素特征与结构特征同步提取”和“原型解构到显型建构机理延续”为操作路径,通过川渝地区历史城镇/街区实证研究,提出历史城镇格局结构要素与建构逻辑、地块图底肌理与聚合关系、街巷局域特征与系统节奏、建筑绝对形态与相对尺度同步提取的空间基因整体识别方法,以及城镇格局结构要素保控+基质空间重构、地块空间图底肌理修补+立体形态调节、街巷空间典型断面整饬+系统节奏保持、建筑空间异化风貌矫正+建构传统赓续的空间基因活态传承方法,以促进历史城镇空间基因保护实践从“依形套式”到“循章衍法”的路径转变。

关键词：历史城镇空间基因构形机理整体识别活态传承川渝地区传统聚落

Tailoring mechanical properties of PμSL 3D-printed structures via size effect

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International Journal of Extreme Manufacturing 2022年第4期4卷 261-268页

作者： Wenqiang Zhang Haitao Ye Xiaobin Feng Wenzhao Zhou ke cao Maoyuan Li Sufeng Fan Yang Lu Department of Mechanical Engineering City University of Hong KongKowloonHong Kong SAR 999077People's Republic of China Nano-Manufacturing Laboratory(NML) City University of Hong Kong Shenzhen Research InstituteShenzhen 518057People's Republic of China Department of Mechanical and Energy Engineering Southern University of Science and TechnologyShenzhen 518055People's Republic of China Hubei key Laboratory of Theory and Application of Advanced Materials Mechanics Wuhan University of TechnologyWuhan 430070People's Republic of China School of Mechano-Electronic Engineering Xidian UniversityXi'an 710071People's Republic of China State key Laboratory of Materials Processing and Die&Mould Technology School of Materials Science and EngineeringHuazhong University of Science and TechnologyWuhan 430074People's Republic of China School of Mechanics and Safety Engineering Zhengzhou UniversityZhengzhou 450001People's Republic of China

Projection micro stereolithography(PμSL)has emerged as a powerful three-dimensional(3D)printing technique for manufacturing polymer structures with micron-scale high resolution at high printing speed,which enables the production of customized 3D microlattices with feature sizes down to several ***,the mechanical properties of as-printed polymers were not systemically studied at the relevant length scales,especially when the feature sizes step into micron/sub-micron level,limiting its reliable performance prediction in micro/nanolattice and other metamaterial *** this work,we demonstrate that PμSL-printed microfibers could become stronger and significantly more ductile with reduced size ranging from 20μm to 60μm,showing an obvious size-dependent mechanical behavior,in which the size decreases to 20μm with a fracture strain up to~100%and fracture strength up to~100 *** size effect enables the tailoring of the material strength and stiffness of PμSL-printed microlattices over a broad range,allowing to fabricate the microlattice metamaterials with desired/tunable mechanical properties for various structural and functional applications.

关键词： 3D printing projection micro-stereolithography(PμSL) size effect microfiber mechanical properties microlattice metamaterial

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自发性颈部淋巴囊肿1例报告

中国口腔颌面外科杂志 2024年第1期22卷 102-104页

作者：曹科达李静王绪凯白晓峰西安交通大学口腔医院口腔颌面外科陕西西安710004 武汉市第六医院口腔科湖北武汉430015 中国医科大学附属口腔医院口腔颌面外科辽宁沈阳110002 浙江大学医学院附属口腔医院口腔颌面外科浙江杭州310006

淋巴囊肿是一种罕见的淋巴系统疾病,颈部手术造成的医源性创伤是其主要病因,而自发性淋巴囊肿更为罕见。本文报告1例颈部自发性淋巴囊肿的临床表现及辅助检查,并结合文献探讨淋巴囊肿的病因、治疗及预后。

关键词：淋巴囊肿自发性淋巴系统淋巴造影

2016—2022年新疆大气污染物时空分布特征

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职业与健康 2024年第7期40卷 949-954页

作者：曹可窦岚李梦王永治范玉玺张世显新疆第二医学院公共卫生学院新疆克拉玛依834000 克拉玛依市疾病预防控制中心性病艾滋病防治科新疆克拉玛依834000 克拉玛依市卫生监督所医疗机构监督科新疆克拉玛依834000

目的分析2016—2022年新疆可吸入颗粒物(inhalable particle,PM_(10))、细颗粒物(fine particle,PM_(2.5))、NO_(2)、SO、CO和O_(3)的时空分布特征,为新疆大气污染防治、环保策略制定等方面提供参考。方法收集整理2016—2022年国控点监... 详细信息

目的分析2016—2022年新疆可吸入颗粒物(inhalable particle,PM_(10))、细颗粒物(fine particle,PM_(2.5))、NO_(2)、SO、CO和O_(3)的时空分布特征,为新疆大气污染防治、环保策略制定等方面提供参考。方法收集整理2016—2022年国控点监测数据,分析新疆各污染物年均、月均及各区域分布特征。结果新疆近7年空气质量整体向好,PM_(10)、PM_(2.5)、SO_(2)、NO_(2)和CO年均浓度整体呈下降趋势,降幅分别为20.04%、24.57%、50.15%、22.56%和33.68%,O_(3)年均浓度无明显变化。PM_(10)、PM_(2.5)、SO_(2)、NO_(2)和CO月均浓度呈“U”型分布,表现为春冬季高、夏季低,O_(3)呈月均浓度呈倒“U”型分布,表现为夏季高、冬季低。PM_(10)和PM_(2.5)达标天数呈上升趋势,而O_(3)达标天数呈下降趋势。新疆各污染物浓度分布具有明显的南北差异性,南疆PM_(10)、PM_(2.5)、SO_(2)、CO和O_(3)浓度高于东疆和北疆,呈现由南向北递减的格局,而NO_(2)高浓度集中在北疆乌鲁木齐市。结论2016—2022年新疆空气质量逐渐改善,但仍存在PM_(10)、PM_(2.5)和O_(3)日均浓度超标现象,今后新疆应重点关注大气颗粒物和O_(3)污染协同控制和区域协同治理。

关键词：大气污染物时空分布新疆

Ferroelastic domain identification and toughening mechanism for yttrium tantalate–zirconium oxide

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Journal of Materials Science & Technology 2022年第32期127卷 78-88页

作者： Cheng Luo Cong Li ke cao Junbao Li Junhui Luo Qinghua Zhang QianQian Zhou Fan Zhang Lin Gu Li Yang Yichun Zhou School of Advanced Materials and Nanotechnology Xidian UniversityXi’an 710126China Frontier Research Center of Thin Films and Coatings for Device Applications Academy of Advanced Interdisciplinary ResearchXidian UniversityXi’an 710126China School of Materials Science and Engineering Xiangtan UniversityXiangtan 411105China Beijing National Laboratory for Condensed Matter Physics Institute of PhysicsChinese Academy of SciencesBeijing 100190China College of Engineering BIC-ESATPeking UniversityBeijing 100871China

Yttrium tantalate(YTaO_(4))is the next generation of higher service temperature thermal barrier coatings(TBCs)materials due to its smaller volume effect in phase change,lower thermal conductivity and unique ferroelastic domain ***,the low fracture toughness limits its *** first characterized the diffraction patterns of variants,and two variants(M_(1)and M_(2))observed in transmission electron microscopy(TEM)results were determined from four possible variants by mechanical *** role of Zr^(4+)doping in ferroelastic toughening was explained in *** the increase of Zr^(4+)doping concentration,the monoclinic angle β and the domain rotation angleαdecrease,*** spontaneous strain component and the principal strain in the main space also have a similar decreasing *** decrease of the ferroelastic domain inversion energy barrier is beneficial to the improvement of fracture *** the results of Vickers indentation,we found that Zr^(4+)could be enriched at the domain boundary to inhibit the generation of *** appropriate amount of Zr^(4+)is conducive to the improvement of fracture toughness,and the excessive Zr^(4+)will reduce the fracture toughness due to the generation of by-product t-ZrO_(2).So,the optimal composition is Y_(0.44)Ta_(0.44)Zr_(0.12)O_(2) and the best fracture toughness(2.9–3.8MPa m^(1/2))is equivalent to the commercial *** result will promote the application of a new generation of TBCs.

关键词： Ferroelastic domain Variants Domain switch TBCs Fracture toughness

Observation of ballistic-diffusive thermal transport in GaN transistors using thermoreflectance thermal imaging

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Rare Metals 2024年第1期43卷 389-394页

作者： Zhi-ke Liu Yang Shen Han-Ling Li Bing-Yang cao key Laboratory for Thermal Science and Power Engineering of Ministry of Education Department of Engineering MechanicsTsinghua UniversityBeijing 100084China

To develop effective thermal management strategies for gallium-nitride (GaN) transistors, it is essential to accurately predict the device junction temperature. Since the width of the heat generation in the devices is comparable to phonon mean free paths (MFPs) of GaN, phonon ballistic transport exists and can significantly affect the heat transport process.

关键词： temperature. transistors GaN

Lewis Base Catalyzed Selenofunctionalization of Alkynes with Acid-Controlled Divergent Chemoselectivity

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Chinese Journal of Chemistry 2024年第14期42卷 1623-1629页

作者： Ling-Ling Chen Ren-Fei cao Hua ke Zhi-Min Chen School of Chemistry and Chemical Engineering Shanghai Key Laboratory for Molecular Engineering of Chiral DrugsShanghai Jiao Tong UniversityShanghai200240 China Engineering Technology Research Center for Environmental Protection Materials Pingxiang UniversityPingxiangJiangxi337055 China

Lewis base catalyzed and Brønsted acid controlled chemodivergent electrophilic selenofunctionalizations of alkynes were developed for the first *** selenium-containing tetrasubstituted alkenes were readily obtained in moderate to excellent yields with complete E/Z *** the substrates were 1-ethynyl naphthol derivatives,linear selenium-containing tetrasubstituted alkenes were produced via intermolecular oxygen nucleophilic attack in the absence of acid additive;in contrast,cyclic selenium-containing tetrasubstituted alkenes were generated through intramolecular carbon nucleophilic capture with the addition of Brønsted acid.

关键词： Alkynes Electrophilic addition Chemoselectivity Lewis base catalysis Selenofunctionalization

Laser-Induced Methanol Decomposition for Ultrafast Hydrogen Production

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Research 2024年第1期2023卷 131-137页

作者： Weiwei cao Yinwu Li Bo Yan Zhiping Zeng Pu Liu Zhuofeng ke Guowei Yang State key Laboratory of Optoelectronic Materials and Technologies Nanotechnology Research CenterSun Yat-sen UniversityGuangzhou 510275P.R.China School of Materials Science and Engineering Sun Yat-sen UniversityGuangzhou 510275P.R.China

Methanol(CH_(3)OH)is a liquid hydrogen(H_(2))source that effectively releases H_(2) and is convenient for *** thermocatalytic CH_(3)OH reforming reaction is used to produce H_(2),but this process needs to undergo high reaction temperature(e.g.,200℃)along with a catalyst and a large amount of carbon dioxide(CO_(2))*** photocatalysis and photothermal catalysis under mild conditions are proposed to replace the traditional thermal catalysis to produce H_(2) from CH_(3)OH,they still inevitably produce CO_(2) emissions that are detrimental to carbon ***,we,for the first time,report an ultrafast and highly selective production of H_(2) without any catalysts and no CO_(2) emission from CH_(3)OH by laser bubbling in liquid(LBL)at room temperature and atmospheric pressure.

关键词： catalysis reforming replace

The tRNA-derived fragment tRF-5022a positively regulates melanogenesis

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Genes & Diseases 2023年第4期10卷 1203-1205页

作者： Si Li Lan Zhang Jing Chen Ling Jiang Chuhan Fu Ao Huang Xinxin Lei Siyu Yang Qinghai Zeng ke cao Department of Dermatology The Third Xiangya HospitalCentral South UniversityChangshaHunan 410013China Department of Oncology The Third Xiangya HospitalCentral South UniversityChangshaHunan 410013China Institute of Chinese Materia Medica Hunan Academy of Chinese MedicineChangshaHunan 410013China

The tRNA-derived fragments(tRFs)are small non-coding RNAs containing fewer than 50 nucleotides that are abundant in humans and have various biological ***,their roles and mechanisms in melanogenesis are *** this study,we firstly investigated the change in the expres-sion profile of tRFs in melanocytes after UVB irradiation through tsRNA ***-induced melanogenesis led to the upregulation of 119 tRFs and the downregulation of 103 tRFs.

关键词： functions melan genesis