Surface-enhanced Raman scattering (SERS) technology is a powerful tool to identify molecular species by collecting molecular spectral signals at the single-molecule level, and has been widely used in medical diagnosis, food safety, biological analysis and other fields. In this paper, the research progress of SERS technology in common bacteria and pathogens was reviewed, and it was expounded that the morphology, type (precious metal and semiconductor substrate), doping elements, hydrogenation time, physical conditions (temperature, pH) of nanostructures were designed and regulated to make it have excellent sensitivity, thus amplifying the application of SERS technology. At the same time, the combination of SERS technology and popular microfluidic technology and CRISRP technology were discussed, as well as the advantages and disadvantages of SERS technology in single molecule detection. Finally, the development prospect of SERS biosensor technology was prospected.

Surface enhanced Raman spectroscopy (SERS) based magnetic immunoassay has attracted considerable attention due to its ability to achieve rapid separation, enrichment, and non-destructive detection of targets with high sensitivity, accuracy and efficiency. Herein, the principle of SERS based magnetic immunoassay and its practical applications were reviewed; SERS based magnetic immunoassay combined with microfluidic, lateral flow analysis, and fluorescence detection techniques was introduced to solve the difficulties in rapid detection of trace amounts, multi-component analysis and identification of different sites for overcoming the drawback in lacking the spatiotemporal resolution. Finally, several methods to improve the sensitivity and feasibility of SERS based magnetic immunoassay were prospected.

Tip-Enhanced Raman Spectroscopy (TERS) technology is a susceptible characterization technique with high spatial resolution. As a non-contact, non-destructive testing system, TERS has gradually become a research hotspot in many disciplines. This paper introduces the principle of TERS technology and the characteristics of metal needle tips, summarizes the research progress of TERS technology in material and life sciences, analyzes the application of TERS technology in teaching, scientific research, and cross-discipline, and discusses the application of TERS technology in chemistry. , physics, biomedicine, and the application of subject teaching and research integration. These research progresses provide essential references for applying TERS technology in material science research, education, and scientific research and help promote further development and application.

Surface-enhanced Raman Scattering (SERS) has been widely used in the field of surface / interface science, spectroscopy, biochemical detection, trace imaging. The metal graphitic nanocapsules were a kind of core-shell nanoparticles whose graphitic shell isolated metal core. It has attracted research attention in the field of biochemical detection analysis and trace imaging due to their high SERS sensitivity, excellent stability and optical properties in complex and harsh biochemical environments. The inherent chemical inertness of the ultrathin graphitic shell could protect the metal core from external factors such as photogenerated hot electrons, reactive oxygen species, and enzymes, which exhibited ultra-stable Raman signal output. Moreover, the multiple characteristic Raman bands (D, G, 2D) of the graphitic shell could be used as Raman signals and internal standard signals to further improve the accuracy of Raman quantitative detection. Notably, the 2D peak as a signal band in the Raman silent region was beneficial to reduce the interference of biomolecules in vivo. This review first introduced the preparation and properties of metal graphitic nanocapsules, and then summarized the application of metal graphitic nanocapsules in detection and imaging based on the SERS. Finally, the prospects and potential of metal graphitic nanocapsules in theranostic were prospected. Keywords: Surface Enhanced Raman Scattering; Metal graphitic nanocapsules; SRES analysis and imaging；Ultra-stability

The anapole state in scattering is a unique optical phenomenon in the field of nanophotonics, which can be analyzed by Mie theory and multipole expansion. For the most common first-order electric anapole, it can be explained by the destructive interference of Cartesian electric dipole and toroidal dipole, with typical far-field scattering suppression and near-field enhancement. In this paper, we describe the basic concept and theory of anapole state firstly, and then summarize the micro-nano structures which support anapole states. Finally in combination with the unique optical properties of anapole states, the potential photonics applications and recent research progress of anapole states in fields such as near-field enhancements, nonlinear optics and lasers are discussed and prospected.

Liquid biopsy is an emerging non-invasive cancer detection technology that offers the advantages of minimal invasiveness and repeatable sampling. It can be used to monitor the occurrence, development, and recurrence of tumors in real-time, as well as to evaluate prognosis and treatment response. In recent years, surface-enhanced Raman scattering (SERS) detection technology based on biological fluids has shown great potential for clinical diagnostic applications due to its rapid, inexpensive, highly sensitive, and specific characteristics. This article provides a brief introduction to the mechanism and advantages of SERS spectroscopy technology, and reviews the progress of non-labeled and labeled SERS techniques in the analysis of body fluid diagnosis. This includes the latest relevant research conducted by our research group on blood, urine, and saliva. Finally, the development prospects of SERS spectroscopy technology in the field of liquid biopsy are analyzed and discussed.

Surface-enhanced Raman spectroscopy (SERS) is a highly sensitive and selective analytical method that enables qualitative and even quantitative analysis of target substances in complex sample environments. In recent years, it has been widely applied in bacterial detection due to its advantages of rapid detection, high sensitivity, and non-destructive analysis. By utilizing the synergistic effect of surface enhancement and Raman scattering, SERS can detect trace amounts of bacteria. This article introduces the basic principle of SERS and its application in bacterial detection. The latest research progress of two strategies, label-based and label-free, based on SERS technology in bacterial detection are summarized. Finally, this article evaluates the challenges and prospects of SERS technology in the field of bacterial detection, providing a reference for further promotion of its application.

Surface enhanced Raman spectroscopy (SERS) has received extensive attention due to its high sensitivity and selectivity. At present, the materials that can be used as SERS substrates are mainly noble metals. The surface plasmon resonance frequency of noble metal nanomaterials is generally in the visible light region, which has a high SERS enhancement factor. However, some problems of noble metal materials also limit their applications. People hope to design a more diverse SERS substrate suitable for a variety of detection molecules, and expect that, similar to metals, high enhancement effects can be achieved through the materials themselves. However, for most semiconductor materials, it is difficult to obtain the enhancement effect induced by surface plasmon resonance (SPR) within the wavelength range (visible region) of Raman excitation lasers, thus necessary to realize its SERS application through the modulation of SPR characteristics. Therefore, the physical enhancement research based on semiconductor itself, especially the synergistic enhancement mechanism of SPR effect, has received more attention. This review will focus on concluding various semiconductor SPR modulation methods, and showing the SERS applications based on semiconductor SPR in recent years.

Plasmon is a kind of electromagnetic mode that exists in the interface between the dielectric and the conductor. Especially for precious metals (gold, silver, copper, platinum, etc.), the freely oscillating electrons on their surface can easily couple with excited photons, inducing the resonance of local surface plasmon. The materials with this unique physical characteristic are generally defined as plasmonic materials, which has attracted extensive attention in the field of nanophotonics due to their superior optical properties of concentrating light beyond the diffraction limit. Among these materials, periodic plasmonic materials exhibit strong tunability and extraordinary light field confinement capabilities, which significantly increase the absorption of photons and enhance the electromagnetic field within the nanometer scale. There have been many synthetic pathways to fabricate plasmonic materials. Typically, the conventional lithography techniques are dominated by ion beam lithography and electron beam lithography; however, such techniques are limited in terms of practical application due to their low-yield, high-cost and excessive reliance on large-scale equipment. Alternatively, the unconventional polystyrene microsphere template technique featuring advantages of high-throughput and low-cost has been prioritized as the universal, facile, efficient and precise synthetic route for the large-scale production. At present, based on this technique, the refined and controllable preparation of high-performance periodic plasmonic materials ranging from tens of nanometers to several micrometers in terms of size has been realized on two-dimensional and three-dimensional scales, such as nanopore array, nanocavity array, nanorod array, nanohole array, nanotriangular array, nanotube array, and some other composite periodic array structures. These periodic plasmonic materials, as an active substrate with high reproducibility and reinforcement, have been widely applied in the field of surface enhanced Raman spectroscopy. In this review, diverse approaches that have been developed to control the self-assembly of polystyrene microspheres and the multi-strategy template modification methods are first briefly introduced followed by the in-depth discussion about the design and synthesis of some representative periodic plasmonic materials. Finally, a comprehensive review about the latest frontier applications of periodic plasmonic materials was presented in the field of surface enhanced Raman spectroscopy. The purpose of this review is to motivate researchers to design ingenious and more practical periodic plasmonic materials, and to promote the rapid development and practical applications of these advanced materials in the field of surface enhanced Raman spectroscopy.

The need for pollution control and the depletion of non-renewable energy sources have made the development of clean energy an urgent need for society. Electrochemical energy technology can efficiently convert chemical energy into electric energy without producing pollutants, which arouses researchers’ interest in recent days. The development of this technology relies heavily on the development of suitable catalysts. However, the study of the reaction mechanism at the solid-liquid interface is difficult due to the complexity of the reactions, the variety of intermediates, their low content and the short duration of their existence, which further limits the development of catalysts. Surface-enhanced Raman spectroscopy, as a molecular fingerprint spectrum, is able to obtain strong and sensitive Raman scattering signals and thus provide good structural information on molecules at the electrode surface interface. This paper focuses on the application of surface-enhanced Raman spectroscopy to the study of the reaction mechanism of fuel cells and lithium batteries. Firstly, this article will introduce the research on the mechanism of enhancing the reaction of intermediate species in fuel cell energy reactions ORR and HOR by surface-enhanced Raman spectroscopy. Secondly, it will introduce the mechanism of electrode reactions and dynamic processes at the solid-liquid interface of lithium batteries through similar strategies using surface-enhanced Raman spectroscopy. Finally, it will summarize the shortcomings of surface-enhanced Raman spectroscopy in the application of electrocatalytic reactions and make future prospects.

Surface enhanced Raman scattering spectroscopy (SERS) is a vibrational spectroscopy technology that can provide molecular fingerprint information, with single-molecule detection sensitivity, sharp peaks, and is widely used in surface science, material science, biomedicine, pharmaceutical analysis, food safety, environmental detection and many other fields due to its advantages of non-calibration, non-destructive, simultaneous detection of multiple components, etc. With the proposal of single-molecule SERS phenomenon in 1997, the surface plasmon effect has received extensive attention, and researchers have focused on the basic scientific problem of surface plasmon phenomenon caused by the interaction between light and nanostructures, and precisely regulated various nanostructures, which has promoted the vigorous development of nanotechnology. However, researches in the past few decades have shown that it is difficult to achieve highly sensitive single-molecule SERS detection by relying only on electromagnetic field enhancement mechanisms and nanostructure construction. Therefore, a series of basic scientific problems such as the surface interaction law of different molecules and nanostructures, the adsorption-desorption behavior of molecules at hot spots, and the interaction mechanism between complex matrices and the molecules to be tested still need to be deeply studied. This review systematically introduces the technical bottlenecks of current SERS detection, including the improvement of sensitivity, the detection of weakly adsorbed substances and the influence of complex matrices, focusing on the methods of concentration enrichment and molecular localization and their applications. The physical, chemical and sorbent strategies used to construct multifunctional SERS substrates are detailed, and current challenges in this field are analyzed. At the same time, new research directions are proposed to realize efficient SERS substrate design ideas that are very important for practical applications.

：Field-effect transistor (FET) has been widely concerned due to their advantages of fast response, high sensitivity and low cost. Here we fabricate a highly sensitive FET biosensor based on MoS2 nanosheets and explore its application for the detection of bovine serum albumin (BSA). Through hydrophobic interaction, BSA is directly combined with MoS2. The device has a detection limit of 5 nM and a large current response to BSA solution in the range of 5 nM to 5 μM. In addition, by analyzing the transfer characteristic curve of the device and the Raman spectrum of MoS2, we have demonstrated that the reason for the increase of the drain-source current (Ids) is the n-type doping phenomenon of BSA on MoS2. We believe that the MoS2 FETs can be expanded into a universal biosensor platform for the sensitive detection of various biomolecules and are expected to be applied to the highly integrated and multiplexed FETs sensor structure.

Gap-enhanced Raman tags (GERTs) represent an innovative optical probe designed based on surface-enhanced Raman scattering (SERS). SERS is a highly sensitive spectroscopic technique used to detect molecular vibrational and transitional information. In the context of SERS, the interaction between molecules and metallic nanostructures, such as Au or Ag nanoparticles, leads to a significant enhancement of Raman scattering signals—a phenomenon capable of amplifying molecular Raman scattering signals by over 10 orders of magnitude. By embedding Raman reporter molecules inside the internal plasmonic metallic nano-junction, GERTs exhibit extraordinary detection sensitivity down to the single-particle detection level; coupled with their ability to provide high-resolution molecular features, GERTs have found extensive applications across a multitude of fields. In this article, we provide a comprehensive introduction to the preparation and optical properties of GERTs, with the goal of realizing their use in practical applications. At the same time, we provide a review of the pioneering use of GERTs as physically unclonable tags, along with their recent advances in biomedical imaging and integrated diagnostics. Finally, we provide a assessment of the challenges GERTs face in real-world application scenarios, providing critical reference points for advancing the clinical translation of GERTs technology. Looking ahead, with further research and development, the novel, stable and super-bright GERTs probes are poised to become a central analytical tool, offering even richer opportunities for practical applications and scientific research.

In recent years, with the rapid development of nanotechnology, surface-enhanced Raman scattering (SERS) technology has been widely applied in various fields such as physical chemistry, materials science, surface science, and biology. Based on zinc oxide/metal composite SERS substrates, which have high Raman enhancement performance and excellent green cycling performance, they are gradually becoming one of the research hotspots in SERS technology. This article reviews the research progress on the mechanism, preparation, regulation, and application of zinc oxide composite SERS substrates, and analyzes the relevant research trends, thereby providing important references for the development of high-performance recyclable SERS substrates and the study of enhancement mechanisms.

In order to study the time evolution of the high-energy electron radiation in the circularly polarized intense laser pulse, a model of the interaction between the high-energy single electron and the intense laser pulse is constructed on the basis of the Lagrangian equation and the electron energy equation. Simulations and calculations are carried out through MATLAB to obtain simulated images of the time evolution of the spatial distribution of electron radiation. The results show that the electromagnetic radiation energy presents a vortex-like spatial distribution with time, and concentrates in the center after about 1000fs; the speed of the radiation concentrating inward gradually slows down over time. In addition, the maximum value of the radiant energy per unit solid angle will also increase with time, and the rate it changes first increases and then decreases. Around 450fs, the radiation energy levels off, then continues to climb slowly until it stabilizes at 1.18×10-12J/cm2 after 1000fs. Thus, ideal electron radiation can be obtained more easily by controlling the interaction time between electrons and laser light.

This article describes a hydrophobic paper based substrate modified with gold and silver alloy nanoparticles, which has a high-density distribution of nanoparticles in the deposition range and high detection sensitivity. It has certain research significance in the field of trace detection. Firstly, different proportions of gold and silver alloy nanoparticles were assembled onto a hydrophobic treated filter paper to improve the plasmonic properties of the substrate. At the same time, high-density nanoparticles were deposited onto a hydrophobic paper substrate through cyclic stacking of the deposition process. In the field of trace detection, the detection limit of trace Rhodamine 6G and crystal violet probe molecular solutions can reach 10-10 M and 10-8 M respectively, and this substrate can be used in the field of pesticide molecular detection, and its detection limit for thiram can reach 10-7 M.

In this paper, Au@AgNPs core-shell nanoparticles are synthesized by using nano-Au seeds template method and then loaded on the poly (styrene butadiene) (SB) fiber membrane made-by electrospinning to prepare Au@AgNPs /SB as the surface enhanced Raman scattering (SERS) flexible substrate. Ultraviolet-visible spectroscopy (UV-vis), transmission electron microscopy (TEM), scanning electron microscopy (SEM) and Raman spectroscopy are used to characterize the morphology and spectral properties of such substrate. Using Rhodamine 6G as a Raman molecular probe, on Au@AgNPs, SERS spectra are recorded after temperature-rise process, showing good thermal tolerance of Au@AgNPs /SB substrate. Therefore, Au@AgNPs /SB substrate could be utilized to detect the target samples pretreated samples at relatively high temperatures, and is conducive to improving the detection sensitivity. Taking the SERS detection of thiram as proof of concept, the limit of detection can be as low as 3.65×10-9 mol/L by using Au@AgNPs /SB extraction of thiram in a hot solution.

In this paper, the fractal structure evolution of aluminum hydroxide colloid particles under aging time 0 - 135 minute was investigated by using synchrotron radiation SAXS technology and other potential characterization methods, including FTIR, SEM, DLS, and Zeta potential.The possible growth mechanism was proposed. The scattering double logarithmic coordinate plots under different aging times showed obvious linearity, indicating that significant differences in the fractal structure of the samples. With the extension of aging time increased from 25 minute to 85 minute, the mass fractal dimension Dm increased from 2.29 to 2.78. The Dm values were in the range of 2.76 - 2.79, with little change between 95 and 135 minutes. This indicated that the primary particles of the system will rapidly reunite from the initial relative dispersion state to larger size clusters and finally form dense gels at the aging time 25 minute - 85 minute. The gel process had been completed, the size of the colloid particles did not change during 95 -135 minute, and the adhesive block may break at 135 minute.

Surface-enhanced fluorescence (SEF) is a cross-space interaction that is affected by the distance between fluorescent molecules and metal nanoparticles. The core-shell structure has become a research topic that has attracted much attention in recent years because of its simple preparation method and easy adjustment of shell thickness. This review introduces several core-shell structures widely used in the study of surface-enhanced fluorescence and their research progress at home and abroad, mainly including the shell structure with metal nanoparticles as the core, the shell structure with metal nanoparticles as the shell, and some other core-shell structures. Then, combined with the research status, the future development of the core-shell structure is prospected.

The mural paintings in the Main Hall of Fengguo Temple are exquisite and unique, with immense historic value and artistic value. However, over time, the murals have suffered from various degrees of damage. One prominent issue is the presence of different types of attachments on the mural surfaces. A condition assessment of the current state of the four types of attachments on the mural surface reveals variations in their distribution. X-ray diffraction and infrared spectrometer are used to analyze the composition of four types of attachments. The results indicate that the four types of attachments are calcium carbonate, unsaturated polyester lacquer, paper fiber, and polyvinyl alcohol formaldehyde and polyvinyl acetate. Environmental monitoring and comprehensive analysis of relevant historic documentation suggest that the main cause of these attachments is closely related to historic conservation. The objective of this study is to systematically reveal the characteristics of the attachments covering the mural surfaces in Fengguo Temple through diagnostic investigation, component analysis, and causation analysis. This research aims to provide a theoretical foundation for the cleaning of the attachments and the conservation of the mural paintings.

In the present study, a solvent-thermal method was used to successfully synthesise hydroxylated nickel chloride with a fullerene-like structure. This synthesized material was implemented as a substrate for surface-enhanced Raman scattering (SERS), and crystal violet (CV) served as a probe molecule to evaluate the SERS performance under an excitation wavelength of 532 nm. The results obtained demonstrate the remarkable sensitivity of the substrate in detecting crystal violet, even at the significantly low concentration of 10-8 mol/L.Furthermore, by introducing sulphur and carefully adjusting the concentration ratios of the reactants, a sulphur-hydroxylated nickel chloride compound was synthesised while retaining its characteristic fullerene-like structure. This incorporation of sulfur into the substrate effectively enhanced the Raman scattering effect, thereby significantly improving its sensitivity for the detection of trace amounts of crystal violet (CV) at an unprecedented concentration as low as 10-11 mol/L, resulting in an improvement of three orders of magnitude. In addition, an examination of the SERS signal from 5000 data points revealed a standard deviation (RSD) of 4.4% for the sulphur-hydroxylated nickel chloride substrate, indicating exceptional reproducibility and uniformity.The morphological and structural characterisation of both hydroxylated and sulphur-hydroxylated nickel chloride was carried out using various analytical techniques such as scanning electron microscopy (SEM), transmission electron microscopy (TEM) and X-ray diffraction (XRD).

Due to the controllable length of the fiber and its unique optical performance, the detection of the fiber SERS substrate is flexible and simple. In this study, silver nanoparticles were modified on the fiber end face using an oil-water separation experimental method, proving that this method can prepare the fiber SERS substrate and effectively enhance Raman signals. We used Crystal violet solution as the analyte to characterize the SERS fiber matrix, and studied the uniformity, sensitivity and stability of the fiber SERS substrate. In practical application, optical fiber substrate was used to detect 4-aminonenenebb thiophenol, which is widely used in the synthesis of Rhodamine 6G and pesticide intermediates. These experimental results demonstrate that the self-assembly method provides a feasible approach for the preparation of fiber SERS substrates.

In recent years, the use of surface-enhanced Raman spectroscopy (SERS) technology to detect biological samples has become a hot topic. Significantly, the application of SERS technology combined with machine learning methods in clinical sample diagnosis has become increasingly mature. Machine learning methods based on unsupervised and supervised algorithms to solve complex samples and large, high-dimensional data, have received high attention. This review describes the relevant applications of SERS technology combined with machine learning methods, especially in the biomedical field. SERS can detect fingerprint information of biological samples using label-free strategies, or indirect SERS detections for tracking biomarkers such as proteins. This review summarizes SERS technology combined with machine learning for disease diagnosis in clinical samples such as blood, urine, and biotissues. In addition, we also summarize their applications on many cellular samples and other complex samples. An overview of the latest advances in this field is provided and this study offers a reference that can be followed by researchers working in SERS bioanalysis.

Fiber-optic sensors offer advantages such as compact size, high flexibility, immunity to electromagnetic interference, lightweight, and suitability for remote signal transmission. These advantages make them well-suited for combining with surface-enhanced Raman Scattering (SERS) technology to create fiber-optic SERS sensors, widely applied in label-free chemical and biological sensing fields. Fiber-optic SERS sensors inherit all the advantages of traditional SERS technology while offering multiplexing capabilities and the ability to continuously and dynamically monitor in special environments. This review primarily covers the development of the structure of fiber-optic SERS sensors and their applications. First, it explores the development and necessity of fiber-optic SERS sensors. Second, it introduces common types of fiber-optic SERS sensors and their fabrication methods. Finally, it briefly outlines the extensive applications and prospects of fiber-optic SERS sensors in various fields.

Interferon-γ (IFN-γ) is an important cytokine, which can be used as a biomarker for disease prevention, diagnosis, and prognosis detection in clinics. To achieve highly sensitive detection of IFN-γ, an aptasensor based on hybrid structure of antibodies and aptamer was developed, which involves two probes. Firstly, 4-Mercaptobenzoic acid (4-MBA) was embedded into Au-Ag Alloy nanoparticles, and then coupled with the aptamer as detection probes. Secondly, magnetic beads modified by antibodies were used as capture probes. When IFN-γ is present, IFN-γ can be captured by both aptamers and antibodies, forming a stable sandwich structure, and obtaining strong Raman signals. On the contrary, when there is not IFN-γ, weak Raman signals are obtained. We optimized the relevant parameters such as volume of 4-MBA and antibody, concentration of aptamer. The experimental results show that this method has high sensitivity and repeatability, with a limit of detection (LOD) of 0.25 pg/mL in PBS. Due to the high recovery rate of this method in serum ranging from 98.7% to 108%, we believe that this aptasensor can achieve the fast and accurate detection of interferon-γ in complex serum environments to meet clinical needs.

In this paper, the centimeter-scale uniform silver nanoparticles (AgNPs) arrays with controllable sizes are prepared by using anodic aluminum oxide template-assisted vacuum thermal evaporation technology. Then, the monolayer MoS2/AgNPs array hybrid structures are obtained by wet transfer method. The surface-enhanced fluorescence (SEF) properties of the hybrid structure are systematically investigated. We find that the fabricated AgNPs arrays could be used as efficient SEF substrates to enhance the fluorescence intensity of monolayer MoS2. Meanwhile, the fluorescence intensity of monolayer MoS2 can been further improved with temperature decreasing. This study may provide a basis for the application of MoS2 in the field of optoelectronic integration.

The molecular structure of modified Rhodamine-6G is complex, and it is easy to decompose. In order to reduce the fluorescence back-bottom of Raman spectrum and improve the stability of signal, the influence of laser wavelength , intensifier proportion, stabilization time, spectral acquisition and other parameters were optimized and analyzed in this paper, and the optimal test conditions were determined: laser wavelength(785nm), intensifier proportion (V sample:V intensifier=2:1), stabilization time of enhancer and sample after mixing(0.5h), spectrum conditions(collection spectrum time 10s, integration times3 ). Under these conditions, the concentration standard solution(100-250mg/L) was tested with three parallel samples. The response value and concentration curve were established with the F1 peak area as the response value, and the concentration linear equation was obtained. The linear correlation coefficient of this method was 0.968, the standard deviation was 3.85%, and the detection limit was 25mg/L, which indicated that this method could be used for the determination of rhodamine-6G concentration. Under light dyes, its concentration and characteristic peak change was determined, the results show that with the increase of time, the dye concentration drops rapidly, as the same time HF1:F2 peak height ratio decreased, F1 relater to C-F bond, and F2 relater to xanthene bond, during the decomposition process, xanthene bond main chain and C-F bond side chain rupture and the C-F bond is more likely to break.

Fouling flash is one of the important reasons that threaten the safe and stable operation of power system, and the difference of fouling type will directly affect the size of flashover voltage. Therefore, timely information on insulator fouling type plays an important role in preventing fouling. To this end, a SAM-ED spectral matching based insulator fouling type detection method is proposed. The hyperspectral data of different fouling type samples are collected, and the noise and other interference factors are removed by black and white correction and multiple scattering correction (MSC); the spectral data are selected by competitive adaptive reweighted sampling (CARS), and the samples are matched with the reference spectra by SAM-ED spectral matching method in the characteristic band and full band range, respectively, and the samples are classified according to the matching results. The experimental results show that the SAM-ED spectral matching method is more effective than the spectral angle matching method and the minimum distance method, and the accuracy of SAM-ED spectral matching based on the full wavelength data can reach 95%, and the accuracy of SAM-ED spectral matching based on the characteristic wavelength data can reach 98.33%.

SERS technique has become one of the powerful tools for monitoring surface/interface reaction processes due to its extremely high surface sensitivity and selectivity. The control of photocatalytic performance is critically based on the well understanding of the reaction process at molecular level. The in-situ monitoring of photocatalytic processes can be realized by the integration of SERS substrate and photocatalyst to provide the interfacial information. In this paper, bifunctional Cu2O-Au composites with both catalytic and SERS activities were synthesized, the SERS enhancement and photocatalytic degradation of methyl orange (MO) were studied as well as the dynamic processes of photocatalytic degradation of MO. The results demonstrate that bifunctional Cu2O-Au composites is beneficial to effectively integrate SERS effect and photocatalytic performance, and the in-situ monitoring of photocatalytic degradation at the Cu2O-Au interfaces was achieved accordingly. The introduction of Au nanoparticles enhanced the SERS effect by two orders of magnitude and double the catalytic degradation performance of Cu2O. In situ monitoring results of MO photocatalytic degradation processes revealed that N=N bond was the most easy to break, and C=C bond was the most difficult to break. The sequence of chemical bond break is N=N > Ph1-N=,= N-Ph2, and Ph1-N=, C-N > Ph-N.

At the beginning of 1970s, conservators at National Museum of China started research on the protection and restoration of ironware. According to the degree of rust, the cultural relics protection and restoration personnel carried out cleaning, rust removal, desalination, bonding and sealing treatments. When examining and reviewing the four iron wares that were protected and restored at that time for fully understanding the previous restorations done on these iron wares, the work uses Fourier Transform Infrared Spectroscopy (FTIR) and Pyrolysis-Gas Chromatography-Mass Spectrometry (Py-GC/MS) to analyze the restoration materials used in the collection of ironware. Py-GC/MS does not require sample pretreatment when analyzing samples, and the samples can be directly analyzed by thermal cracking, and the operation is relatively simple. In addition, this method requires a small amount of sample. It can not only provide a scientific evaluation the repair materials in iron wares, but also provide important guidance for evaluating the protection and restoration methods used in the past and the long-term preservation of iron wares.

In order to focus coherent light and image through scattering media in noisy environment, a score assessment algorithm is proposed to optimize the phase distribution of the incident wavefront. The basic idea of the score assessment algorithm is to mark the phase value according to the target intensity in the optimization process. Binary phase optimization is exploited to increase the speed of the program, which can be applied to dynamic scattering media. Compared with the ant colony algorithm, it is found that the score assessment algorithm can achieve a focus under strong disturbance, while the ant colony algorithm is invalid in noisy environment. In experiments, it is found that the intensity of the target signal is enhanced 71.4 times over the average speckle intensity using the score assessment algorithm. Therefore, the score assessment algorithm should be considered firstly in the application of biological imaging, photoelectric detection and other fields.

Combing the metal organic frameworks (MOFs) with surface enhanced Raman scattering (SERS) hybrid substrates have been to a focus of high-efficiency SERS detection. In this study, we developed a MOF-SERS substrate by immobilizing the thioctic acid-modified gold nanoparticles (AuNPs) onto the surface of UiO-66 through electrostatic interactions. The effect factor (EF) of UiO-66/AuNPs substrates for the cationic malachite green, methylene blue and saffron T were 2.12×104, 4.46×104 and 7.20×104, two orders of magnitude higher than the EF of 1.43×102, 2.54×102 and 1.73×102 for the anionic lemon yellow, sunset yellow and congo red. Overall, UiO-66/AuNPs substrates can selectively improve the detection sensitivity of cationic pigments by electrostatic adsorption and are a highly efficient SERS sensor material with promising applications.

Fourier transform infrared spectroscopy combined with curve fitting technology was used to study the ginger medicinal materials stored for 5 years, in order to explore the composition changes of ginger medicinal materials stored for 5 years. The results showed that the original infrared spectra were similar, and the main substances reflected in the spectra were volatile oils, flavonoids, sugars, amino acids, etc. Local amplification and second derivative processing of original spectra of 1300 ~ 1450 cm-1 with large differences in spectra showed that 1384cm-1 and 1410cm-1 had significant differences in peak strength and peak position, and it was inferred that the content and internal structure of compounds containing isopropyl and tert-butyl had changed. Combined with absorbance ratio method and curve fitting area quantitative analysis, the content of volatile oil of 22 species of ginger showed a decreasing trend and the content of carbohydrate showed an increasing trend with the change of storage time. The results showed that Fourier transform infrared spectroscopy combined with curve fitting could provide an effective method for quality analysis of ginger.

Spatial self-phase modulation (SSPM) is a third-order nonlinear optical response, also known as optical Kerr effect. The physics mechanism of SSPM is laser-induced nonlocal electron coherence, which is a collective excitation behavior, nonlinear optical response, and emergence phenomenon. Electrons in the matters move with optical frequency driven by light field and obtain phase determined by the external field. Electrons in separated domains preserve fixed phase difference and nonlocal coherence emerges. The parallel components of diffractive light form a group of concentric conical emissions, resulting in coherence rings in the far field screen. This phenomenon is SSPM. All-optical switching can be achieved based on laser-induced electron coherence in quantum materials, functioning as a “transistor” in photonics, because it can realize using a weak light to control a strong light. This article briefly reviews the investigations towards SSPM physics mechanism, as well as its potential applications in all-optical switching, emphasizing on the new progress and microscopic mechanism of SSPM.

Surface-enhanced Raman Scattering (SERS) is an analytical method based on molecular vibration fingerprint information, which has high sensitivity, good selectivity, nondestructive and on-site detection, and is free from the interference of water system. It has potential application in the fields of biological analysis and early diagnosis. Compared with natural enzyme, nanoenzyme as an artificial mimic enzyme presents the advantages of easy and scalable preparation, diversity of enzymatic activity via rational design as well as long-term environmental stability. Metal-organic framework (MOF) with mesoporous crystal structure, large specific surface area could be easily synthesized, which is beneficial to immobilization of other nanomaterials to improve stability and realize the multifunctional performance. This short review concerns on nano-enzyme, MOF and SERS substrate assembly to advance the figure of analytical merit, and focuses on the current explorations of MOF/nanozyme/SERS platform in the field of biomedical analysis and prospects.

Surface-enhanced Raman spectroscopy (SERS) is a powerful technique for fingerprinting analysis of substances, which has been widely used in biosensing and chemical analysis. The fabrication of SERS substrates with well-ordered nanostructures is crucial for high reliability and stability in Raman trace-detection. The development of precise, large-scale, and efficient fabrication methods for nanostructured substrates is still a challenge to SERS used in practice so far. In this work, we propose a parallel-laser nanofabrication method for nanostructure arrays, combining microsphere-lenses with gold nanoholes (ML/AuNHs) for ultrasensitive hybrid SERS substrates. The AuNHs are fabricated on the bottom surfaces of ML by the photonic nanojets for the hybrid structures. The effect of process parameters, i.e., the pulsed laser energy, the ML diameter, and the thickness of gold film, on the quality of the nanoholes is investigated. The parameters of laser fabrication are optimized for the diameter of AuNHs down to 215 nm. Furthermore, the optical regulation in ML/AuNHs is theoretically investigated, including self-aligned focusing to the hotspots, optical whispering-gallery modes (WGMs), and directional antenna. The mechanism of Raman enhancement via the ML/AuNHs is therefore revealed. The limit of detection by the ML/AuNHs down to 10-10 M for 4-nitrobenzenethiol (4-NBT) molecules is also demonstrated, which is two orders of magnitude lower than using the AuNHs without ML coupling. This work presents a simple and efficient parallel-laser nanofabrication method for the highly-sensitive SERS substrates in the future applications.

Benzo(a)pyrene (Bap) is a typical organic pollutant in the environment, which is enriched in the human body through continuous biological cycles and can cause chronic damage to the organism. In order to rapidly detect benzopyrene and complete trace analysis, a new disposable sensor for the separation and detection of poisons was constructed by combining thin layer chromatography plates (TLC) with surface-enhanced Raman scattering (SERS) to detect benzopyrene. This method has high sensitivity, easy operation and other advantages. It can complete the on-site rapid analysis and detection of poisons, and effectively overcome the problems of difficult operation and high technical requirements of the current detection method for benzopyrene, which has certain practical significance.

Molecular profiling and accurate damage analysis of complex biomolecular events in tumor cells are critical to the diagnosis and treatment of cancer. However, due to sensitivity limitation and dynamic and complex nature of apoptosis process, label-free detection of cellular DNA damage during cancer therapeutic treatment, at the DNA bases level, is still a huge challenge. Herein, by designed preparation of novel and uniform plasmonic sunflower-like assembly gold (Au) nanostructure that capable of efficient DNA capture and providing high-density “hot spots” for SERS enhancement, we succeeded in sensitive and reliable SERS detection of DNA damage in apoptotic cancer cells at the DNA bases level. The chemical structure damage of cellular DNA caused by electrostimulus-induced cell apoptosis was revealed and discriminated at the bases level, for the first time, by label-free SERS detection with the nano-sunflowers. The SERS results showed that the external electrostimulus (at 1.2 V, for 5 min) was almost harmless to normal healthy cells but it caused pronounced double strands break and Adenine (A) base damage in cancer cell DNAs, which effectively destroyed the reproduction and transcribe of DNA to harass cancer cell mitosis and ultimately induce cell apoptosis. The finding provides deep insights into molecular genomic DNA damages of cancer cells during theranostic process, and the method would open a new avenue for the study of genetically related diseases.

Green pigments are often used in jungle camouflage. This article compares the similarity between 10 commonly used green pigments and plant leaves, including chromium green, alkaline magenta green, alizarin green, iron green, blue pigments(cobalt blue, ultramarine, cobalt sulfonated phthalocyanine, phthalocyanine blue, iron blue), and yellow pigments (bismuth yellow, iron yellow) mixtures, using two spectral similarity evaluation methods. Among them, the similarity between chrome green pigment and plant leaves is the highest, and the similarity in sub bands is good. The types of pigments are distinguished by the first order differential method of spectroscopy, and chromium green pigments with high similarity to plants can be identified by the spectral recognition index method. The spectral recognition index method can quickly extract target information, greatly improving the recognition speed.