Simultaneous Activation of Short‐Wave Infrared (SWIR) Light and Paramagnetism by a Functionalized Shell for High Penetration and Spatial Resolution Theranostics

Nanoparticle emitting short‐wave infrared (SWIR) light has received increased attention in the molecular imaging field due to its deeper tissue penetration, fast imaging, high sensitivity, and resolution. The simultaneously activated SWIR excited directly by an 808 nm laser and T₁‐weighted magnetic resonance imaging (MRI) signal are found in one single‐shell nanoparticle NaErF₄@NaGdF₄ (Er@Gd), which is used as a dual‐modality imaging contrast agent in vivo to accurately determine the position of tumors. The conjugated cypate is then aggregated on the surface of Er@Gd@SiO₂‐Cy/bovine serum albumin. With the guidance of dual modality imaging, photothermal therapy is effectively used to ablate tumors in a mouse model. The design of single‐shell nanomaterial activation of SWIR imaging and MRI signals is expected to provide a new strategy for high penetration and spatial resolution cancer theranostics.     

Crystalline damage in silicon wafers and 'rare event' failure introduced by low-energy mechanical impact

We used X-ray diffraction imaging to detect and characterize mechanical damage introduced to 300 mm silicon wafers by low impact energy exerted on the wafer edge. Maps of crystalline damage show a correlation between the damage size, the magnitude of the impact energy and the location of the impact point. We demonstrate the existence of crystalline non-visual defects; crystalline defects that appear in the X-Ray diffraction images but not in optical microscopy or scanning electron microscope. We propose a mechanism of crystalline damage formation at low impact energies based on finite element analysis and high-resolution synchrotron white beam transmission X-ray topography. Finally, we propose the concept of 'rare-event' to described relatively low rate of occurrence of wafer failure by fracture within semiconductor manufacturing facilities.     

Yb3+/Er3+共掺ZnF2粉末上转换发光特性研究

为了研究ZnF₂作为基质材料、稀土离子Yb3+和Er3+共掺摩尔分数不同时的发光性能,采用高温固相法,在820℃时制备稀土掺杂ZnF₂样品,并对各个样品进行上转换发射光谱测试。将激发功率与上转换发射功率进行曲线拟合,确定Yb3+和Er3+光子吸收过程。结果表明,在980nm半导体激光器激发下,样品在可见光区域内存在533nm,555nm和655nm 3个上转换发射峰,发射的红光强度大于绿光强度,吸收光子数目依次为1.73,1.75,1.88,确定3个发射峰均对应于双光子吸收。此研究说明稀土离子掺杂ZnF₂材料将在上转换红色荧光粉领域有重要的应用前景。     

复合土工膜在松子坑水库土坝中的应用

论述了复合土工膜在深圳市松子坑供水调节水库土坝防渗结构中的使用情况，对采用复合土工膜防渗的土坝坝体防渗结构设计，稳定分析，复合土工模选择，铺设及接缝粘接施工，防渗结构施工及工序质量控制方面的较为详细的介绍。     

考虑分级开挖的深基坑支护计算

 提出了考虑深基坑变形的一种新的支护结构计算方法——弯杆计算法，在弯杆法的有限元计算中， 通过变换座标的方式考虑上一级开挖的变形，从而达到考虑分级开挖的工况。实例验算表明，该程序能够计算出支护结构变形的变化趋势，并给出了简要的自编计算程序框图。     

土石坝中测斜管接头处预留沉降量的探讨

预留沉降量的确定是土石坝中安装测斜管常见的问题，国内目前尚无定量的技术标准。文章结合小浪底土石坝中测斜管接头处安装预留沉降量的确认过程，提出了具有一定参考意义的量化指标。     

阿哈水库粘土斜墙土坝渗压计的安装埋设

根据大坝安全监测和运行管理的需要，对阿哈水库粘土斜墙上坝补设了10个渗压观测点，渗压观测选用差动电阻式渗压计，渗压计埋设采用钻孔埋设法。此工程已于1996年12月实施完毕，并获得成功。     

深厚覆盖层岩组划分及主要工程地质问题

深厚覆盖具有结构松散、岩性不连续，在水平和垂直方向有较大变化、成因类型复杂、物理力学性质呈较大不均匀性的特点。深厚覆盖层可按其成因、物质组成、结构特征及厚度变化等作为岩组划分的依据。宝兴水电站坝址覆盖层按此依据可划分为６大岩组。     

掺稀土离子液体激光器的研究进展

综合介绍了掺稀土离子液体激光器的主要发展历程,分析了掺稀土离子液体激光材料研究过程中需要解决的主要问题包括降低无辐射跃迁、增大溶解度和减少热致折射率梯度引起的光偏折损耗等.重点介绍了稀土离子在溶液中的无辐射跃迁机理以及降低无辐射跃迁的措施.     

Plasmon-Assisted Self-Encrypted All-Optical Memory

All-optical responsive nanomaterials, which can rapidly switch between two stable states, have been regarded as the next-generation memories due to their potential to realize binary information storage and implement on-chip, integrated photonic neuromorphic systems. Rare earth oxides are preeminent candidates owing to their extraordinary luminescent stability and narrow optical transitions. However, due to the lack of simple and effective optical switches, it is difficult to realize all-optical data storage, encoding, and retrieval by pure rare earth-doped luminescent nanoparticles. Here, a rapid and high-contrast of 10⁴ luminescent switching of Y₂O₃:Eu³⁺ nanoparticle between the enhancement and quenching states is achieved by employing the strong light confinement and ultrafast thermal response of localized surface plasmon resonance. A self-encrypted all-optical memory is presented with optical information writing, encryption, reading, and re-writing, and a high-sensitivity synaptic response of emitters to frequency and light intensity flux, which can be harnessed to encrypt information flows and promote convenient and high-security information encryption. Such a convenient and secure plasmonic thermally assisted self-encrypting luminescent switch paves the way for constructing high-performance stimuli-responsive rare earth oxide crystals on demand and expanding their applications in various data encryption, anti-counterfeiting, and rewritable colouration devices.