Integration of Biomolecules with Metal–Organic Frameworks

Owing to the progressive development of metal–organic‐frameworks (MOFs) synthetic processes and considerable potential applications in last decade, integrating biomolecules into MOFs has recently gain considerable attention. Biomolecules, including lipids, oligopeptides, nucleic acids, and proteins have been readily incorporated into MOF systems via versatile formulation methods. The formed biomolecule‐MOF hybrid structures have shown promising prospects in various fields, such as antitumor treatment, gene delivery, biomolecular sensing, and nanomotor device. By optimizing biomolecule integration methods while overcoming existing challenges, biomolecule‐integrated MOF platforms are very promising to generate more practical applications.     

Tailoring Chiroptical Activity of Iron Disulfide Quantum Dot Hydrogels with Circularly Polarized Light

Chiral inorganic nanomaterials have recently attracted significant attention because of their many important applications, such as in asymmetric catalysis and chiral sensing. Here, chiral iron disulfide quantum dots (FeS₂ QDs) are synthesized via chirality transfer using l/d ‐cysteine (Cys) as chiral ligands. The chiral FeS₂ QDs are coassembled with two gelators to produce a cogel (l ‐ or d ‐[Gel+FeS₂]) with a g‐factor value of ±0.06. Interestingly, the cogels display intense circularly polarized luminescence. More significantly, the degree of twisting (twist pitch) and the diameter of the cogels can be markedly regulated by illumination with circularly polarized light (CPL) in the ranges of 120–213 and 37–65 nm, respectively, which is caused by the CPL‐induced electron transfer. This research opens the way for the design of chiroptical devices with a wide range of functions and applications.     

轮对几何参数及踏面缺陷光电检测方法

提出了一种基于光电检测技术的车辆轮对综合参数自动检测方法。运用精密激光位移传感、CCD及数字图像处理技术,实现了轮缘厚度、轮缘高度、车轮直径等尺寸参数的非接触自动检测;再结合精密运动控制,以及车轴和圆周方向的快速激光扫描,实现了踏面擦伤和剥离等缺陷参数的分类和识别。实验结果表明,基于上述测量方法的检测系统,其尺寸参数测量精度为0.2mm,擦伤深度测量精度为0.1mm,剥离长度测量精度为0.5mm,能满足车辆段修现场使用的要求。     

Design of transmission blazed binary gratings for optical limiting with the form-birefringence theory

The structure of transmission blazed binary gratings for optical limiting is designed with the form-birefringence theory. This kind of grating has subwavelength features, can imitate the transmission blazed grating effectively, and has higher efficiencies than a transmission blazed grating with a subwavelength structure. The diffraction efficiencies are calculated and analyzed. For the normal incident light with 10.6 microm wavelength, the transmissivities for the designed grating at 0 degrees deviation angle for TE and TM polarizations are 0.05% and 5.09%, respectively, which are basically identical to the results of the finite-difference time-domain method. The diffraction efficiencies of the first transmitted order for TE and TM polarizations are 93.95% and 83.88%, respectively.     

High‐Performance Water Electrolysis System with Double Nanostructured Superaerophobic Electrodes

Catalysts screening and structural optimization are both essential for pursuing a high‐efficient water electrolysis system (WES) with reduced energy supply. This study demonstrates an advanced WES with double superaerophobic electrodes, which are achieved by constructing a nanostructured NiMo alloy and NiFe layered double hydroxide (NiFe‐LDH) films for hydrogen evolution and oxygen evolution reactions, respectively. The superaerophobic property gives rise to significantly reduced adhesion forces to gas bubbles and thereby accelerates the hydrogen and oxygen bubble releasing behaviors. Benefited from these metrics and the high intrinsic activities of catalysts, this WES affords an early onset potential (≈1.5 V) for water splitting and ultrafast catalytic current density increase (≈0.83 mA mV^?1), resulting in ≈2.69 times higher performance compared to the commercial Pt/C and IrO₂/C catalysts based counterpart under 1.9 V. Moreover, enhanced performance at high temperature as well as prominent stability further demonstrate the practical application of this WES.     

基于趋势相似性特征的异常工况监测方法研究

当前火力发电生产过程中,多元变量检测方法难以实现多元非平稳过程变量异常工况监测。对此,首先计算多元变量之间在固定时间窗口宽度内数据之间的趋势相似性,采用所得到的趋势相似性作为监控特征。其次,采用主元分析方法对所得到相似性特征序列进行降维,对降维后所得到的主元空间趋势相似性特征序列进行监控。最后,以T2统计量作为监测指标,依据T2统计量与其控制阈值T2α的大小关系产生告警信号,从而达到有效监控多元非平稳过程变量的目的。通过在华北电网某300 MW火电机组的应用,验证了所提出方法的有效性与可靠性。该方法较好地解决了多元非平稳过程的检测问题,对于相关研究与应用具有借鉴意义。     

Cr(CO)_n(n=1-5)与C_6 H_6相互作用的密度泛函研究

用密度泛函理论在B3LYP/LANL2DZ基组水平上对(η~x-C_6H_6)Cr(CO)_n(x=1-6;n=1-5)复合物体系的可能构型进行了自由优化及相互作用能的计算,研究了不同羰基数对复合物稳定性、苯和羰基铬相互作用的影响,并对苯和羰基铬相互作用进行了NBO分析。得到以下结论:(1)当n≤3时,苯与Cr(CO)_n以η~6配位;当n≥4时,苯与Cr(CO)_n以η~2配位;(2)最稳定复合物中随羰基数的增加Cr-C_(benzene)平均键长增长,最大二面角H-C-C-H偏离碳环的角度随复合物对称性降低而逐渐增大;(3)当n为奇数时,复合物相互作用主要表现为苯C-C键的π轨道和Cr-CO键的σ反键轨道;当n为偶数时,复合物相互作用主要表现为苯C-C键的π轨道或π~*轨道与Cr的孤对电子轨道;(4)复合物羰基数越多,最稳定复合物的相互作用能数值越大,稳定性越小。     

基于HCS12单片机的智能导航系统的设计

智能化和信息化是未来汽车的发展趋势,汽车的电子化程度被看作是现代汽车水平的重要标志.本文针对现代汽车的智能化要求设计了基于HCS12单片机的智能导航系统.系统以单片机HCS12和光电传感器为核心配合各外围电路模块实现自动寻迹功能.文中给出了各功能模块的硬件电路框图和软件设计思路.实验结果证明,该智能车导航系统能很好地满足小车在前进过程中对速度调节的快速响应和稳态误差小的要求.     

基于FPGA的PWM与定时计数器IP核的设计

基于硬核嵌入式CPU中的PWM／定时计数器模块与FPGA的广泛应用,本文提出了一种软件式的PWM／定时计数器数字逻辑电路的设计思想。用硬件描述语言HDL编写总线接口、功能逻辑与外部I／O电路,并描述了硬件驱动程序的设计过程。对其结果进行了软件仿真并定制到NIOSII中进行调试,实验结果证明,该设计具有很好的实际效果。