Asymmetric Non-Fullerene Small Molecule Acceptor with Unidirectional Non-Fused π-Bridge and Extended Terminal Group for High-Efficiency Organic Solar Cells

We designed and synthesized an asymmetric non-fullerene small molecule acceptor (NF-SMA) IDT-TNIC with an A–D–π–A structure, based on an indacenodithiophene (IDT) central core, with a unidirectional non-fused alkylthio-thiophene (T) π-bridge, and 2-(3-oxo-2,3-dihydro-1H-cyclopenta[b]naphthalen-1-ylidene)malononitrile (NIC) extended terminal groups. IDT-TNIC molecules still maintain a good coplanar structure, which benefits from the non-covalent conformational locks (NCL) between O···S and S···S. The asymmetric structure increases the molecular dipole moment, and the extended terminal group broadens the absorption of the material, resulting in an excellent photovoltaic performance of IDT-TNIC. The photovoltaic device, based on PBDB-T:IDT-TNIC, exhibits an energetic PCE of 11.32% with a high V_oc of 0.87 V, high J_sc of 19.85 mA cm⁻², and a low energy loss of 0.57 eV. More importantly, IDT-TNICs with asymmetric structures show a superior property compared to symmetric IDT-Ns. The results demonstrate that it is an effectual strategy to enhance the properties of asymmetric A–D–π–A-based NF-SMAs with non-fused NCL π-bridges and extended terminal groups.     

基于差分隐私的Android物理传感器侧信道防御方法

Android物理传感器侧信道防御研究主要针对以移动设备传感器为媒介的隐私泄露攻击.当前的防御方案主要为预防检测、虚拟键盘随机化等.然而,防御过程中不可控的用户决策以及层出不穷的新型侧信道攻击,导致传统方案无法从根本上解决基于物理传感器的隐私泄露威胁.针对上述问题,提出了一种基于差分隐私的Android物理传感器侧信道防御方法.通过注入少量的特殊分布噪声,混淆传感器原始数据,进而干扰侧信道构建过程.如何在保证传感器相关功能正常运行与用户体验的前提下,尽可能降低侧信道攻击成功率是面临的最大困难.通过设计并实现传感器相关功能抽取工具SensorTainter,对APP中传感器相关功能进行分析与分类,计算相关功能正常运行时能够承受的传感器数据混淆范围.依据对47 144个APP以及典型传感器侧信道攻击的实验分析结果,证明该防御方案能够有效限制传感器侧信道攻击,单次点击事件攻击的准确率最高减少27个百分点.由于在Android应用框架层构建,该防御方案对于用户完全透明,具有很好的扩展能力.     

分子对接方法在药物发现之外领域的应用

基于分子对接的反向虚拟筛选方法在药物靶点确定、老药新用以及药物副作用/毒理研究领域具有重要的应用前景,吸引了药物发现领域研究人员的广泛关注.首先对分子对接方法和蛋白质数据库进行细致的介绍,然后列举目前可以用于反向虚拟筛选的网络服务器,并列举该方法在药物设计领域的一些具体应用,最后对该方法目前所存在的问题进行讨论.

     

侧链多阳离子型氟化聚芴醚阴离子交换膜及其全钒液流电池性能

阳离子基团的分布对阴离子交换膜的微观相态和阴离子传导率有显著的影响.为开发全钒液流电池用高性能阴离子交换膜,本文通过向含有二甲胺基团的氟化聚芴醚前驱体接枝含阳离子烷基链的方式,合成了具有相似离子交换容量的一系列侧链多阳离子型氟化聚芴醚.实验结果表明,多阳离子侧链的引入能促进微观相分离的形成并提升阴离子传导率.同时,侧链...     

集装箱绿色装卸工艺综合评价指标体系的研究

为实现港口绿色装卸,建立了集装箱绿色装卸工艺的综合评价体系。通过对国内港口集装箱码头装卸工艺的分析与研究,利用模糊数学理论进行集装箱码头各类评价指标的权重分析,建立基于港口集装箱码头绿色装卸工艺的综合评价体系。集装箱绿色装卸工艺评价体系的建立,有利于港口集装箱码头装卸工艺优化配置,符合国家绿色环保的方针。     

Truly Concomitant and Independently Expressed Short‐ and Long‐Term Plasticity in a Bi2O2Se‐Based Three‐Terminal Memristor

Concomitance of diverse synaptic plasticity across different timescales produces complex cognitive processes. To achieve comparable cognitive complexity in memristive neuromorphic systems, devices that are capable of emulating short‐term (STP) and long‐term plasticity (LTP) concomitantly are essential. In existing memristors, however, STP and LTP can only be induced selectively because of the inability to be decoupled using different loci and mechanisms. In this work, the first demonstration of truly concomitant STP and LTP is reported in a three‐terminal memristor that uses independent physical phenomena to represent each form of plasticity. The emerging layered material Bi₂O₂Se is used for memristors for the first time, opening up the prospects for ultrathin, high‐speed, and low‐power neuromorphic devices. The concerted action of STP and LTP allows full‐range modulation of the transient synaptic efficacy, from depression to facilitation, by stimulus frequency or intensity, providing a versatile device platform for neuromorphic function implementation. A heuristic recurrent neural circuitry model is developed to simulate the intricate “sleep–wake cycle autoregulation” process, in which the concomitance of STP and LTP is posited as a key factor in enabling this neural homeostasis. This work sheds new light on the development of generic memristor platforms for highly dynamic neuromorphic computing.     

内啮合渐开线齿轮传动法隙计算的几何分析法

通过几何分析的方法，导出了内啮合渐开线齿轮传动中心距略变小时，法向齿侧间隙的计算公式，供齿轮传动设计计算之用。     

Engineered Sleeping Beauty Transposon as Efficient System to Optimize Chimp Adenoviral Production

Sleeping Beauty (SB) is the first DNA transposon employed for efficient transposition in vertebrate cells, opening new applications for genetic engineering and gene therapies. A transposon-based gene delivery system holds the favourable features of non-viral vectors and an attractive safety profile. Here, we employed SB to engineer HEK293 cells for optimizing the production of a chimpanzee Adenovector (chAd) belonging to the Human Mastadenovirus C species. To date, chAd vectors are employed in several clinical settings for infectious diseases, last but not least COVID-19. A robust, efficient and quick viral vector production could advance the clinical application of chAd vectors. To this aim, we firstly swapped the hAd5 E1 with chAd-C E1 gene by using the CRISPR/Cas9 system. We demonstrated that in the absence of human Ad5 E1, chimp Ad-C E1 gene did not support HEK293 survival. To improve chAd-C vector production, we engineered HEK293 cells to stably express the chAd-C precursor terminal protein (ch.pTP), which plays a crucial role in chimpanzee Adenoviral DNA replication. The results indicate that exogenous ch.pTP expression significantly ameliorate the packaging and amplification of recombinant chAd-C vectors thus, the engineered HEK293ch.pTP cells could represent a superior packaging cell line for the production of these vectors.     

热网监控系统GPRS通讯终端的设计与实现

针对 GPRS 热网监控系统通讯终端常采用"主-从"轮询通信方式单一的缺点,通过优化故障报警上传通信机制,实现了一种"主-从"与"从-主"有机结合的双向通信系统,不仅大大提高了运行速度,还提高了系统的可靠性。通讯终端采用高性能的32位 ARM 处理器,以嵌入式实时操作系统为核心,使用专用的 GPRS 模块 MC39i 实现换热站与调度中心之间的数据通信。阐述了系统的设计思路和终端软、硬件的设计结构,重点介绍了从-主通信方式—故障报警的设计方法。     

Broadband MIMO Antenna System for 5G Operations in Mobile Phones

A broadband 8‐antenna multiple‐input and multiple‐output (MIMO) system working for 5G new radio N77 (3.3‐4.2 GHz) in mobile terminals is proposed. In particular, each antenna element/unit consists of a monopole‐type meandered branch and an inverted U‐shaped self‐isolated antenna branch; and the antenna unit is fed by the meandered branch. The antenna unit has two resonances generated separately by each branch of the antenna unit. Since the monopole couples strongly with the self‐isolated antenna element that has the inherent self‐isolation characteristics, quite good isolation for the broadband 8‐antenna MIMO system can be obtained. The results such as antenna efficiency, radiation patterns, envelope correlation coefficient, and channel capacity are also presented.