论不定式分句逻辑主语的构成

不定式分句的逻辑主语比较复杂,分为带主语的不定式分句和不带主语的不定式分句。带主语的不定式分句的逻辑主语可以由不同的介词引导;不带主语的不定式分句的逻辑主语可以在主句中或语境中体现出来,要从表层结构和深层结构分别进行剖析。学好不定式分句的逻辑主语对我们掌握不定式分句的句法功能,正确划分英语句子成分,有效地翻译句子,解释英语中的歧义现象等有很大的帮助。     

Anisotropic fluoride nanocrystals modulated by facet-specific passivation and their disordered surfaces

Rutile-type fluorides have been proven to be active components in the context of emerging antiferr-omagnetic devices. However, controlled synthesis of low-dimensional, in particular two-dimensional (2D), fluorides in a predictable and deterministic manner remains unrealized because of a lack of efficient anisotropic control, which impedes their further development in reduced dimensions. We report here that altered passivation of {110} growing facets can direct the synthesis of rutile-type fluoride nanocrystals into well-defined zero-dimensional (0D) particulates, one-dimensional (1D) rods and 2D sheets in a colloidal approach. The obtained nanocrystals show positive exchange bias and enhanced magnetic transition temperature from the coexistence of long-range antiferromagnetic order and disordered surface spins, making them strong alternatives for flexible magnetic devices and sensors.     

Surface superconductivity in the type II Weyl semimetal TaIrTe4

The search for unconventional superconductivity in Weyl semimetal materials is currently an exciting pursuit, since such superconducting phases could potentially be topologically non-trivial and host exotic Majorana modes. The layered material TaIrTe₄ is a newly predicted time-reversal invariant type II Weyl semimetal with the minimum number of Weyl points. Here, we report the discovery of surface superconductivity in Weyl semimetal TaIrTe₄. Our scanning tunneling microscopy/spectroscopy (STM/STS) visualizes Fermi arc surface states of TaIrTe₄ that are consistent with the previous angle-resolved photoemission spectroscopy results. By a systematic study based on STS at ultralow temperature, we observe uniform superconducting gaps on the sample surface. The superconductivity is further confirmed by electrical transport measurements at ultralow temperature, with an onset transition temperature (T_c) up to 1.54 K being observed. The normalized upper critical field h*(T/T_c) behavior and the stability of the superconductivity against the ferromagnet indicate that the discovered superconductivity is unconventional with the p-wave pairing. The systematic STS, and thickness- and angular-dependent transport measurements reveal that the detected superconductivity is quasi-1D and occurs in the surface states. The discovery of the surface superconductivity in TaIrTe₄ provides a new novel platform to explore topological superconductivity and Majorana modes.     

Regulating surface wrinkles using light

Regulating existing micro and nano wrinkle structures into desired configurations is urgently necessary yet remains challenging, especially modulating wrinkle direction and location on demand. In this work, we propose a novel light-controlled strategy for surface wrinkles, which can dynamically and precisely regulate all basic characteristics of wrinkles, including wavelength, amplitude, direction and location (λ, A, θ and L_c), and arbitrarily tune wrinkle topographies in two dimensions (2D). By considering the bidirectional Poisson''s effect and soft boundary conditions, a modified theoretical model depicting the relation between stress distributions and the basic characteristics was developed to reveal the mechanical mechanism of the regulation strategy. Furthermore, the resulting 2D ordered wrinkles can be used as a dynamic optical grating and a smart template to reversibly regulate the morphology of various functional materials. This study will pave the way for wrinkle regulation and guide fabrication technology for functional wrinkled surfaces.     

基于SWMM的地表径流量与城市下垫面和降雨特征关系的空间分析——以中国科学院大学雁栖湖校区为例

以中国科学院大学雁栖湖校区为例,用城市雨洪管理模型（SWMM）模拟2016-2017年48场降雨事件中所有子汇水小区的径流过程;在验证可靠的基础上,探讨径流量空间分布与降雨和下垫面的关系,是开展防汛工作的重要基础。结果表明,径流量高值区多位于沥青小区,而低值区多位于绿地小区。沥青最易产流,绿地最不易产流。砌砖易产生中等量级的径流,混凝土较砌砖更易产流,但二者在不同降雨事件下的产流规律相似。沥青小区和砌砖小区的地表径流量均与坡度呈极显著或显著线性正相关关系。对沥青-砌砖和沥青-绿地小区,将非渗透面积比例（PIC）降至60%可明显控制其暴雨和大雨径流。要明显控制大暴雨径流,可将沥青-绿地小区的PIC降至30%以下;但降低PIC对沥青-砌砖小区大暴雨径流的控制作用不明显。研究结果可为海绵城市建设和城市内涝防洪提供理论依据和决策建议。     

液滴撞击凹凸槽道表面液膜的动态演变

为研究固体表面结构对液滴撞击液膜后演变行为的影响规律,采用CLSVOF方法模拟液滴撞击不同尺寸槽道上的表面液膜的流动过程,获得不同槽道高度和宽度时液滴撞击液膜后的演变行为,探索撞击速度、液膜黏度和表面张力对撞击后液膜铺展行为、水花飞溅高度和二次液滴形成的影响。结果表明,槽道结构对液滴撞击液膜后的动态行为具有显著影响,随着槽道高度的增加,冠状水花厚度越薄,越容易产生二次液滴;随着液膜黏度的增大,则抑制冠状水花形成与二次液滴的产生;液膜表面张力减小时,射流更加明显,二次液滴数更多,飞溅现象提前,冠状水花消失时间延后。     

HP3中共形极小曲面的几何

通过扭映射π：CP⁷→HP³构造出HP³中曲率为4/7,4/19,4/27的6个共形极小二维球面的例子.由于扭映射π：CP²ⁿ⁺¹→HPⁿ给出了CP²ⁿ⁺¹的水平极小曲面与HPⁿ中极小曲面的一个自然等同,利用Bolton等得出的在CPⁿ中常曲率共形极小二维球面的结论,根据CHEN Xiaodong和JIAO Xiaoxiang给出的HPⁿ中常曲率共形极小二维球面的一般方法,构造出HPⁿ中的共形极小曲面的例子.     

AutoCAD中标注表面粗糙度的方法

参照GB／T131—2006的ISO表面结构标准,针对AutoCAD软件中未提供粗糙度标注的命令或工具问题．提出了利用定义块和AutoLISP语言编程两种方法,实现CAD环境下工程图样表面粗糙度符号的标注。     

歇后语的结构及其规范化

歇后语有外在表层结构和内在深层结构，其内在深层结构才是歇后语安身立命之点，构成歇后内在深层结构的前后两部分是矛盾统一体，两者有“同”有“异”。“同”与“异”科学地结合于一体，才构成规范化的歇后语，无“异”不能使歇后语既形象，生动，风越又表达一定的意义，无“同”则不能使其前后两部分合乎逻辑和谐地统一起来，有无“同”是鉴别是否是规范化歇后语的试金石，不合深层构造规律的歇后语是不规范的歇后语，应该沟汰。     

氧化镁和氧化钇掺杂对纳米氧化铝粉末的影响

本文研究了用均相共沉淀法合成氧化铝陶瓷粉末的同时合成氧化镁、氧化钇等掺杂氧化物,发现在掺杂量不大时,同时合成的掺杂氧化物以填隙固溶体方式固溶于立方γ氧化铝中,并且几乎不影响铝氧键性质、晶格常数和衍射波矢,但掺杂使氧化物细化,比表面增大,用此法合成的粉末聚集比较厉害,在粉末中有晶化颗粒存在．