二茂铁苯基衍生物的综合化学实验设计

介绍了一个综合化学实验,涉及二茂铁苯基衍生物的合成、光物理和电化学性质的表征。该实验难度适中,综合运用了多种表征方法和测试手段,将大学基础化学理论、基本实验技能与金属有机领域的学术研究相结合。采用逆合成分析法设计了“一锅法”水相合成路线,旨在帮助学生树立绿色化学的概念以及培养可持续发展的思想。实验运用了紫外-可见吸收光谱和电化学方法对目标化合物的光物理和电化学性质进行研究,并结合量化计算手段详细比较了给电子基团和吸电子基团对分子电荷分布带来的影响。通过以科研反哺教学的模式,本实验不仅使学生掌握了基本的科研训练,而且培养了他们的综合实验素质。

电化学合成苯并噁噻嗪二氧化物实验的课程思政设计

有机电化学合成技术以电子代替传统有机反应的氧化还原剂,具有经济高效、环境友好、可持续发展等特点。通过将电化学合成苯并噁噻嗪二氧化物的科研成果转化为本科生实验,可以让学生建立“绿色化学”的理念,了解有机电化学合成技术对服务人类生态文明、国家需求和维护人民生命健康的重要意义,从而提高学生的专业认同感和社会责任感。通过将课程思政渗透到实验教学的全过程,全方位培养学生的科学思维、科学能力和科学素养。

Technology and engineering application of cross area HVDC interconnection system high-precision simulation modeling based on ADPSS

In recent years, a large number of high voltage direct current(HVDC) transmission projects have been connected to AC systems. This has started to have an impact on AC/DC hybrid power grids, particularly receiving terminal power grids. An HVDC system is a large-scale power electronic integrated nonlinear system, and it includes a primary system and a control and protection system. Hence, the precision and degree of detail of HVDC systems directly affect the actual effect of simulation. In recent years, in the case of the normal operation and failure of AC power grids, the abnormal fluctuation and even locking of HVDC systems caused by the inappropriate strategies of the control and protection system component have strongly affected power grids. This has significantly affected the safety and stability of receiving power grids and normal operation. In this study, the actual engineering HVDC control logic provided by a manufacturer is analyzed and simulated based on the user defined component library of the ADPSS electromagnetic transient calculation program, and an HVDC control model based on an actual system is established. The accuracy of the DC control custom model based on ADPSS is verified through the simulation of an actual power grid.

第11届全国大学生化学实验邀请赛有机化学实验试题解析

介绍了第11届全国大学生化学实验邀请赛有机化学实验操作试题的命题思路,并对实验中存在的问题及成绩进行了分析。

A review of ultrafast laser micro/nano fabrication:Material processing,surface/interface controlling,and devices fabrication

Ultrafast laser processing technology has offered a wide range of opportunities in micro/nano fabrication and other fields such as nanotechnology,biotechnology,energy science,and photonics due to its controllable processing precision,diverse processing capabilities,and broad material adaptability.The processing abilities and applications of the ultrafast laser still need more exploration.In the field of material processing,controlling the atomic scale structure in nanomaterials is challenging.Complex effects exist in ultrafast laser surface/interface processing,making it difficult to modulate the nanostructure and properties of the surface/interface as required.In the ultrafast laser fabrication of micro functional devices,the processing ability needs to be improved.Here,we review the research progress of ultrafast laser micro/nano fabrication in the areas of material processing,surface/interface controlling,and micro functional devices fabrication.Several useful ultrafast laser processing methods and applications in these areas are introduced.With various processing effects and abilities,the ultrafast laser processing technology has demonstrated application values in multiple fields from science to industry.

Ultrafast laser processing of camouflaged metals by topography inherited multistep removal for information encryption

Surfaces with micro-nanoscale structures show different optical responses,including infrared reflection,thermal radiation,and protective coloration.Direct realization of structure camouflage is important for material functionalities.However,external cloaks or coatings are necessary in structure camouflage,which limits the surface functionality.Here,we propose a novel strategy for the direct structure camouflage through topography inherited removal(TIR)with ultrafast laser,featuring pristine topography preservation and scattering surface fabrication.After multistep TIR,pristine topographies are partially and uniformly removed to preserve the original designed structures.Optical response changes show the suppression of specular reflection by uniformizing reflected light intensity to a low level on the inherited surface.We produce various structure camouflages on large scaled substrates,and demonstrate applications of information encryption in code extraction and word recognition through structure camouflage.The proposed strategy opens opportunities for infrared camouflage and other technologies,such as thermal management,device security,and information encryption.

Side-Chain Type Ferrocene Macrocycles

A class of side-chain type ferrocene macrocycles with a radially conjugated system is introduced in this study.The stereo configurations of these ferrocene rings were determined through single-crystal X-ray diffraction analysis.Notably,in the solid state,the ferrocene rings exhibit a distinctive herringbone stacking pattern imposed by a ferrocene-to-ring host−guest interaction.Through UV−vis absorption spectroscopy,electrochemical measurements,and theoretical calculations,valuable insights into the electronic properties of these rings were obtained.In addition,the single crystal of macrocycle A_(2)B demonstrates a second-order nonlinear optical response.As a class of organometallic nanorings,this work holds great potential for further exploration in the fields of organometallic chemistry,molecular electronics,and host−guest chemistry.

Ultrafast laser processing of silk films by bulging and ablation for optical functional devices

Organic proteins are attractive owing to their unique optical properties,remarkable mechanical characteristics,and biocompatibility.Manufacturing multifunctional structures on organic protein films is essential for practical applications;however,the controllable fabrication of specific structures remains challenging.Herein,we propose a strategy for creating specific structures on silk film surfaces by modulating the bulging and ablation of organic materials.Unique surface morphologies such as bulges and craters with continuously varying diameters were generated based on the controlled ultrafast laser-induced crystal-form transition and plasma ablation of the silk protein.Owing to the anisotropic optical properties of the bulge/crater structures with different periods,the fabricated organic films can be used for large-scale inkless color printing.By simultaneously engineering bulge/crater structures,we designed and demonstrated organic film-based optical functional devices that achieves holographic imaging and optical focusing.This study provides a promising strategy for the fabrication of multifunctional micro/nanostructures that can broaden the potential applications of organic materials.

Nanoscale multi-beam lithography of photonic crystals with ultrafast laser

Photonic crystals are utilized in many noteworthy applications like optical communications,light flow control,and quantum optics.Photonic crystal with nanoscale structure is important for the manipulation of light propagation in visible and near-infrared range.Herein,we propose a novel multi beam lithography method to fabricate photonic crystal with nanoscale structure without cracking.Using multi-beam ultrafast laser processing and etching,parallel channels with subwavelength gap are obtained in yttrium aluminum garnet crystal.Combining optical simulation based on Debye diffraction,we experimentally show the gap width of parallel channels can be controlled at nanoscale by changing phase holograms.With the superimposed phase hologram designing,functional structures of complicated channel arrays distribution can be created in crystal.Optical gratings of different periods are fabricated,which can diffract incident light in particular ways.This approach can efficiently manufacture nanostructures with controllable gap,and offer an alternative to the fabrication of complex photonic crystal for integrated photonics applications.

纳米碳分子——合成化学的魅力

碳材料的发展极大地推动了人类科技的进步。碳材料通过碳原子之间不同的键合方式、结构和排列,使其具有丰富的性质,并且更多新型碳材料还不断地被发现或合成出来。作为新型碳材料的纳米碳分子由于其本身所拥有的潜在优良性质,在有机电子学、材料科学如生物材料等领域具有广阔的应用前景,因此被誉为是未来最有开发前景的材料。在过去的四十年里,新型纳米碳分子的发现和创造已彻底改变了碳材料的格局,打开了一扇通往全新科学领域的大门。本文重点介绍了近年来具有新颖拓扑结构的纳米碳分子的结构特征以及如何通过有机合成的手段对其进行精准构筑。

When nanocarbon science meets with molecular machine:A new type of mechanically interlocked molecules(MIMs)

The discovery of new carbon nanomaterials such as fullerenes,carbon nanotubes,graphene,and graphyne has always driven the development of various fields of science[1].The arrangement of carbon atoms largely influences their properties.In the past decade,the atomic-precision synthesis and study of molecular nanocarbons,which is the sub-structures of larger carbon nanostructures,have attracted huge attention[2].Among them,the synthesis of cycloparaphenylene(CPP)(the substructure of carbon nanotubes)has been developed considerably since 2008[3].Recently,topologically complex nanocarbon[4]starting from CPP or oligoparaphenylene-derived carbon nanohoop has been explored as a new type of MIM,which undoubtedly revolutionizes a wide range of sciences,especially in the field of molecular machine(Fig.1)[5].

Digital Twin Framework and Its Application to Power Grid Online Analysis

Digital twin(DT)framework is introduced in the context of application for power grid online analysis.In the development process of a new power grid real-time online analysis system,an online analysis digital twin(OADT)has been implemented to realize the new online analysis architecture.The OADT approach is presented and its prominent features are discussed.The presentation,discussion,and performance testing are based on a large-scale grid network model(40K+buses),exported directly from the EMS system of an actual power grid.A plan to apply the OADT approach to digitize power grid dispatching rules is also outlined.

Sliding wear behavior of fully nanotwinned Cu alloys

Highly nanotwinned(NT) metals have advantages such as high strength,good ductility,favorable corrosion resistance,and thermal stability.It has been demonstrated that the introduction of high density NT microstructures can enhance the tribological properties of metals.However,the influence of the microstructure and the composition of NT alloys on the tribological behavior are not clear.In this work,the sliding wear behavior of fully NT materials,specifically Cu-Al and Cu-Ni alloys,are studied by a nanoscratch technique using a nanoindenter.The effects of microstructure and chemical composition on the wear properties are also studied.The results show that the chemical composition has an obvious influence on the wear resistance and microstructural deformation.For NT Cu-Al alloys,the hardness and sliding wear resistance improve with increased Al content from Cu-2 wt.%Al to Cu-6 wt.%Al.NT Cu-10 wt.%Ni alloy shows even better wear resistance than Cu-6 wt.%Al.The microstructural analysis shows that NT Cu alloys with higher wear resistance correspond to a smaller deformation-affected zone.The improvement of sliding wear properties of Cu-Al alloys with higher Al content may be ascribed to their decreased stacking fault energy.NT Cu-Ni alloy shows better wear resistance than Cu-Al alloy,this may be related to the formation of intermetallic compounds in Cu-Al system.This study broadens the knowledge about tribological properties of NT materials and provides a potential method to optimize their sliding wear resistance by altering the chemical composition of NT Cu alloys.

A New Solution Architecture for Online Power System Analysis

The current DSA system used in the dispatching control centers in China is a near real-time analysis system with response speed in the order of minutes.Based on a review of the state-of-the-art in online analysis and discussion of distributed data processing and computation architecture patterns,a new online analysis architecture is proposed.The primary goal of the new architecture is to increase the online analysis response speed to the order of seconds.A reference implementation of the proposed online analysis architecture to validate the feasibility of implementing the architecture and some performance testing results are presented.

Real-time Online Analysis of Power Grid

The unprecedented operational complexity and se-curity risks in operating the Chinese UHV AC/DC power grid calls for a new generation of real-time(sec-order)online analysis systems to provide decision support.Our recent Digital Twin based online analysis research and development work to address the needs is presented.In addition,a high-level solution architec-ture for the future real-time online analysis systems is proposed for realizing:a)The delay of the virtual model to mirror the physical power grid is in sub-sec range;b)The downstream online analysis applications could have sec-order responsiveness.

Micro/nano processing of natural silk fibers with near-field enhanced ultrafast laser

Silkworm silk fiber is an attractive material owing to its remarkable mechanical characteristics,excellent optical properties,and good biocompatibility and biodegradability.However,nano-processing of the silk fiber is still a challenge limiting its applications in nanoengineering and related fields.Herein,we report localized near-field enhancement-assisted ablation with an ultrafast laser to break this bottleneck.Localized processing of silk fiber,including nano-holing,nano-grooving,and cutting could retain the key molecular structure building blocks and the pristine functionality of the silk fiber.An extremely narrow nanohole with a width of^64 nm was successfully achieved.The processed silk fiber can be used to transfer micro/nanoparticles and drugs,showing potential for biomedical engineering.The processing strategy developed in this study can also be extended to other materials,paving a new way for fabricating functional nanostructures with precisely controlled size and morphology.

Graph Computing and Its Application in Power Grid Analysis

Approaches to apply graph computing to power grid analysis are systematically explained using real-world application examples.Through exploring the nature of the power grid and the characteristics of power grid analysis,the guidelines for selecting appropriate graph computing techniques for the application to power grid analysis are outlined.A custom graph model for representing the power grid for the analysis and simulation purpose and an in-memory computing(IMC)based graph-centric approach with a shared-everything architecture are introduced.Graph algorithms,including network topology processing and subgraph processing,and graph computing application scenarios,including in-memory computing,contingency analysis,and Common Information Model(CIM)model merge,are presented.