Fast and Efficient CRISPR/Cas9 Genome Editing In Vivo Enabled by Bioreducible Lipid and Messenger RNA Nanoparticles

A main challenge to broaden the biomedical application of CRISPR/Cas9 (clustered regularly interspaced short palindromic repeat (CRISPR) associated protein 9) genome editing technique is the delivery of Cas9 nuclease and single‐guide RNA (sgRNA) into the specific cell and organ. An effective and very fast CRISPR/Cas9 genome editing in vitro and in vivo enabled by bioreducible lipid/Cas9 messenger RNA (mRNA) nanoparticle is reported. BAMEA‐O16B, a lipid nanoparticle integrated with disulfide bonds, can efficiently deliver Cas9 mRNA and sgRNA into cells while releasing RNA in response to the reductive intracellular environment for genome editing as fast as 24 h post mRNA delivery. It is demonstrated that the simultaneous delivery of Cas9 mRNA and sgRNA using BAMEA‐O16B knocks out green fluorescent protein (GFP) expression of human embryonic kidney cells with efficiency up to 90%. Moreover, the intravenous injection of BAMEA‐O16B/Cas9 mRNA/sgRNA nanoparticle effectively accumulates in hepatocytes, and knocks down proprotein convertase subtilisin/kexin type 9 level in mouse serum down to 20% of nontreatment. The leading lipid nanoparticle, BAMEA‐O16B, represents one of the most efficient CRISPR/Cas9 delivery nanocarriers reported so far, and it can broaden the therapeutic promise of mRNA and CRISPR/Cas9 technique further.     

Scanning Nanowelding Lithography for Rewritable One‐Step Patterning of Sub‐50 nm High‐Aspect‐Ratio Metal Nanostructures

The development of a new nanolithographic strategy, named scanning nanowelding lithography (SNWL), for the one‐step fabrication of arbitrary high‐aspect‐ratio nanostructures of metal is reported in this study. Different from conventional pattern transfer and additive printing strategies which require subtraction or addition of materials, SNWL makes use of a sharp scanning tip to reshape metal thin films or existing nanostructures into desirable high‐aspect‐ratio patterns, through a cold‐welding effect of metal at the nanoscale. As a consequence, SNWL can easily fabricate, in one step and at ambient conditions, sub‐50 nm metal nanowalls with remarkable aspect ratio >5, which are found to be strong waveguide of light. More importantly, SNWL outweighs the existing strategies in terms of the unique ability to erase the as‐made nanostructures and rewrite them into other shapes and orientations on‐demand. Taking advantages of the serial and rewriting capabilities of SNWL, the smart information storage–erasure of Morse codes is demonstrated. SNWL is a promising method to construct arbitrary high‐aspect‐ratio nanostructure arrays that are highly desirable for biological, medical, optical, electronic, and information applications.     

自动铺放成型热塑性复合材料的非等温结晶动力学研究

利用差示扫描量热仪结合Avrami方程研究玻璃纤维增强聚丙烯复合材料自动铺放成型过程非等温结晶动力学,推导非等温结晶动力学模型,并通过构建冷压辊下方铺层的冷却模型,将结晶动力学模型和传热模型相结合,设定自动铺放成型过程中的冷却条件,探讨冷却速率及冷却时间对基体材料结晶行为的影响,求解出不同冷却速率下的最大铺放速率。研究结果表明:铺层树脂基体的结晶度随冷却速率的增大而依次减小;随着冷却速率的提高,树脂结晶起始温度和结晶完成温度均向低温方向移动,且树脂相对结晶度随温度变化规律接近反S形曲线;自动铺放成型实验件的压缩强度及层间剪切强度随着铺层结晶度的增大基本呈增大趋势,而冲击强度与铺层结晶度的变化趋势完全相反,随着结晶度的增大,材料韧性越差。     

采用吸气管过热度调节的户式空气源采暖空调热水三用机

简要介绍户式空气源采暖空调热水三用机的项目背景、技术原理、技术路线。针对三用机的特殊技术要求,首次提出吸气管过热度的定义以及采用电子膨胀阀PID调节吸气管过热度的新概念,利用该调节方法研制一台三用机,并按行业标准进行型式试验检测。测试结果表明,三用机达到国标的节能等级,并可高效制热、低温采暖,以及实现高效率的采暖、空调、热水、空调＋热水等功能。     

Grain‐Boundary “Patches” by In Situ Conversion to Enhance Perovskite Solar Cells Stability

The power conversion efficiency of organic–inorganic hybrid perovskite solar cells has increased rapidly, but the device stability remains a big challenge. Previous studies show the grain boundary (GB) can facilitate ion migration and initiate device degradation. Herein, methimazole (MMI) is employed for the first time to construct a surface “patch” by in situ converting residual PbI₂ at GBs. The resultant MMI–PbI₂ complex can effectively suppress ion migration and inhibit diffusion of the metal electrodes. The origin of the surface “patch” effect and their working mechanisms are investigated experimentally and theoretically at the microscopic level. It hence demonstrates a simple and effective method to prolong the device stability in the context of GB engineering, which could be extensively applied to perovskite‐based optoelectronics.     

ISO 14031：2013《环境管理环境绩效评价指南》助力组织环境绩效评价

环境绩效评价是对组织是否实现其环境目标的评价,旨在以持续的方式向相关方提供相关和可验证的信息。它既是组织对内、对外沟通环境绩效的一项重要程序和手段,也是组织进行环境管理的一项重要工具。ISO14031：2013《环境管理环境绩效评价指南》提供了完整的环境绩效评价PDCA模式,以及一整套环境绩效指标库,各行业可据此选择和确定具有行业及学科特点的环境绩效评价参数,实施更加有效的环境绩效评价。     

高活性催化剂制备乙烯共聚产物的结构与性能：（I）？…

新型高活性催化剂ＴｉＣｌ４、Ｔｉ（ＯＢｕ）４／ＭｇＣｌ２、ＳｉＯ２、ＺｎＣｌ２／醇／ＡｌＲ３体系催化乙烯气相齐聚和共聚合,制得了一系列线性低密度塑性体和极低密度弹性全。用ＤＳＣ、ＦＴ－ＩＲ研究了它们的支化结构、结晶度、结晶与熔融行为。结果表明新型高活性催化剂具有和齐聚性能相关的很好的催化乙烯与１－丁烯共聚合的性能;当共聚单体中１－丁烯含量由７％（体积,不同）增加到２６％,产物的支化度（乙基数／１０     

新型CO2可逆离子液体体系制备纤维素膜的结构与性能

以新型CO2可逆离子液体CO2/DBU/DMSO体系经溶解、沉积制备出纤维素膜,系统探究了沉积浴的种类、溶剂组成及溶解时间对纤维素膜结构与性能的影响。研究表明,经该体系充分溶解并水沉积得到的纤维素膜具有Ⅰ型与Ⅱ型结晶并存的结构,与原纤维素的固有结晶结构相近。所得纤维素膜具有良好的力学性能,拉伸强度达到55.9MPa,断裂伸长率为9%。因此,新型CO2可逆离子液体体系的运用,为简便易行制备性能良好的纤维素膜提供了重要的技术途径。     

High-precision deformation monitoring algorithm for GBSAR system: rail determination phase error compensation

In recent years, the repeat-pass GBSAR (ground based synthetic aperture radar) system has demonstrated its capacity to acquire deformation. Nevertheless, in a variety of applications, it needs to measure the deformation with the precision up to 0.1 mm, which could not be reached by utilizing the traditional PS (permanent scatterer) algorithm in most cases. Generally, one of the main reasons could be summarized into the phase error caused by the rail determination error, because the precision of rail determination might degrade during long working hours. However, the traditional PS algorithm could not compensate for the phase error caused by the rail determination error. In order to solve the problems, we modify the conventional PS algorithm. Firstly, we deduced the transformation relationship between the rail determination error and its corresponding interferometric phase error. Then, the phase errors caused by the atmosphere and the rail determination error were jointly compensated. The experimental data, which were obtained in Fangshan District in Beijing (China), were used to test and verify the performance of the new algorithm. After the comparison between the results processed by the new algorithm and those processed by the traditional algorithm, the proposed method demonstrated its ability to obtain high-precision deformation.     

宽带无线通信系统中的MAC处理板设计

介绍了宽带无线通信系统中MAC处理板的硬件结构,并详细介绍了PCI接口芯片的控制逻辑设计和串行收发器RocketIO的在线部分配置。