光学加工过程中高次非球面的三坐标测量数据处理

三坐标轮廓检测是大口径高次非球面确定性加工过程中的主要面形测量手段。由于原始三坐标数据包含较大的检测误差,无法直接应用于加工过程,本文提出了一组数据处理算法对误差进行全面去除。首先,对获取的检测数据采用基于球心曲面重建的测头半径补偿算法进行测头半径误差补偿,然后对补偿后数据进行坐标系旋转平移误差去除,最后对提取的检测面形残差进行基于KNN的残差噪点过滤。其中,提出的基于球心曲面重建的测头半径补偿算法通过引入一个高精度的测头球心包络面拟合模型,来计算各检测点的测头半径补偿向量,仿真实验证明:算法补偿精度达到RMS<4 nm;提出的基于KNN的残差噪点过滤算法,通过采用插值方法提高样本空间密度和优化噪声度量值的计算,提高了噪点的识别敏感度并实现了噪点的自动化去除。最终根据整个误差清理算法构建了检测点云处理软件,应用实践表明其有效提高了镜面加工过程中检测点云的数据处理精度和效率。     

BaMnO3 nanostructures: Simple ultrasonic fabrication and novel catalytic agent toward oxygen evolution of water splitting reaction

In the current paper, the main aim is to fabricate the BaMnO₃ nanostructures via the sonochemical route. The various factor, including precursors, reaction time and power of sonication can affect the shape, size, and purity of the samples. We utilized X-ray diffraction (XRD), scanning electron microscope (SEM), transmission electron microscopy (TEM), Fourier transform infrared spectroscopy (FT-IR), and X-ray energy dispersive spectroscopy (EDS) to characterize the BaMnO₃ nanostructures. The optical property of BaMnO₃ nanostructures was explored by Ultraviolet–visible spectroscopy (UV–vis) and the energy gap was suitable for catalytic activity (about 2.75 eV). Changing the precursor can affect the size, nanoparticle shape, architectures, and uniformity of the samples. We employed the BaMnO₃ nanostructures for O₂ evolution reaction as catalysts. It can observe that increasing the homogeneity of the catalysts can increase the efficiency of the Oxygen evolution reaction. The maximum amount of the O₂ evolution and the highest TOF and TON are related to nanoplate disc using barium salicylate as a precursor of barium. As a result, we can nominate the BaMnO₃ nanostructures as an effective and novel catalyst for water-splitting reaction.     

Molecular beam epitaxy growth of quantum devices

The inherent fragility and surface/interface-sensitivity of quantum devices demand fabrication techniques under very clean environment. Here, I briefly introduces several techniques based on molecular beam epitaxy growth on pre-patterned substrates which enable us to directly prepare in-plane nanostructures and heterostructures in ultrahigh vacuum. The molecular beam epitaxy-based fabrication techniques are especially useful in constructing the high-quality devices and circuits for solid-state quantum computing in a scalable way.     

Onion-structured transition metal dichalcogenide nanoparticles by laser fabrication in liquids and atmospheres

Since the discovery of transition metal dichalcogenide (TMDC) nanoparticles (NPs) with the onion-like structure, many efforts have been made to develop their fabrication methods. Laser fabrication (LF) is one of the most promising methods to prepare onion-structured TMDC (or OS-TMDC) NPs due to its green, flexible, and scalable syntheses. In this mini-review article, we systematically introduce various laser-induced OS-TMDC (especially the OS-MoS₂) NPs, their formation mechanism, properties, and applications. The preparation routes mainly include laser ablation in liquids and atmospheres, and laser irradiation in liquids. The various formation mechanisms are then introduced based on the different preparation routes, to describe the formations of the corresponding OS-NPs. Finally, some interesting properties and novel applications of these NPs are briefly demonstrated, and a short outlook is also given. This review could help to understand the progress of the laser-induced OS-TMDC NPs and their applications.     

Mechanically fabricated Metal–organic framework/resin composite nanoparticles for efficient basic catalysis

Zeolitic imidazolate framework‐8 (ZIF‐8) was successfully composited with an anionic basic resin 201 × 7 (717‐resin) to provide a novel ZIF‐8/717‐resin composite. Its catalytic activity toward the Knoevenagel condensation reaction was evaluated. Results showed that ZIF‐8/717‐resin composite could efficiently catalyze this reaction, affording the corresponding products in good to excellent yields. Good functional group tolerance, mild reaction conditions, good stability and reusability of the catalyst are the major features of present protocol.     

用于电催化析氧反应电极的制备策略

随着能源枯竭和环境污染等问题的日益严重,开发清洁可再生能源及相关新型技术迫在眉睫。近年来,水分解、金属-空气电池等电化学能源储存和转换技术得到人们的广泛关注。电催化析氧反应(Oxygen evolution reaction,OER)是其中的一个关键反应,大量高性能的OER电催化剂不断见诸报道。除了材料本征催化活性的影响,不同的电极制备方式同样会对催化剂性能的发挥起到重要作用,越来越多的研究者致力于探索高效OER电极的设计与制备方法。本综述从方法论的角度,详细介绍了目前高效OER电极的制备策略,讨论了各类制备方式的优势和不足,总结了相关工作的最新研究进展,概述了新型电极的制备方法。最后,对电极制备策略的发展方向进行了总结与展望。     

Recent advances in fabrication of monolayer colloidal crystals and their inverse replicas

Monolayer colloidal crystals(MCCs)are two-dimensional(2D)colloidal crystals consisting of a monolayer of monodisperse colloidal particles arrayed with a 2D periodic order.In recent years,MCCs have attracted intensive interest because they can act as 2D photonic crystals and be used as versatile templates for fabrication of various 2D nanostructure arrays.In this review,we provide an overview of the recent progress in the controllable fabrication of MCCs and their inverse replicas.First,some newly-developed methods for the self-assembly of MCCs based on different strategies including interfacial assembly and convective assembly are introduced.Second,some representative novel methods regarding the fabrication of various functional2D inverse replicas of MCCs,such as 2D arrays of nanobowls,nanocaps,and hollow spheres,as well as 2D monolayer inverse opals(MIOs),are described.In addition,the potential applications of MCCs and their inverse replicas are discussed.     

Systematic Control of the Excited‐State Dynamics and Carrier‐Transport Properties of Functionalized Benzo[ghi]perylene and Coronene Derivatives

A series of benzo[ghi]perylene (Bp) and coronene (Cor) derivatives substituted with electron‐withdrawing methoxycarbonyl (COOMe) or electron‐donating methoxyl (MeO) groups was synthesized. The electrochemical, spectroscopic, and photophysical properties of these compounds were investigated by cyclic voltammetry, steady‐state and time‐resolved spectroscopy, and quantum‐yield measurements. Introduction of suitable substituents onto the aromatic rings enabled control of electrochemical and spectroscopic behavior. Examination of excited‐state dynamics revealed that fluorescence quantum yields increased with increasing number of COOMe groups in both Bp and Cor derivatives, consistent with the findings of DFT calculations. Single‐crystal analysis allowed the performance of field‐effect transistors containing single crystals of the derivatives to be rationalized.     

Research progress on pesticide residue detection based on microfluidic technology

The problem of pesticide residue contamination has attracted widespread attention and poses a risk to human health. The current traditional pesticide residue detection methods have difficulty meeting rapid and diverse field screening requirements. Microfluidic technology integrates functions from sample preparation to detection, showing great potential for quick and accurate high-throughput detection of pesticide residues. This paper reviews the latest research progress on microfluidic technology for pesticide residue detection. First, the commonly used microfluidic materials are summarized, including silicon, glass, paper, polydimethylsiloxane, and polymethyl methacrylate. We evaluated their advantages and disadvantages in pesticide residue detection applications. Second, the current pesticide residue detection technology based on microfluidics and its application to real samples are summarized. Finally, we discuss this technology's present challenges and future research directions. This study is expected to provide a reference for the future development of microfluidic technology for pesticide residue detection.     

高效率GaN基高压LED芯片的制备及COB封装

为提升GaN基高压LED芯片的出光性能,优化了芯片发光单元之间隔离沟槽的宽度.当隔离沟槽宽度为20μm时,芯片的电学性能和光学性能最优.当注入电流为20 mA时,正向电压为50.72 V,输出光功率为373.64 mW,电光转换效率为36.83％.采用镜面铝基板和陶瓷基板进行了4颗芯片串联形式的COB封装.镜面铝基板的热导率和反射率均高于陶瓷基板,可提升HV-LED器件在大注入电流和高温时的发光性能.当注入电流为20 mA且基板温度为20℃时,镜面铝基板封装的HV-LED器件的正向电压是198.9 V,发光效率达122.2 lm/W.