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Copper is a crucial catalyst in the synthesis of graphdiyne (GDY). However, as catalysts, the final fate of the copper ions has hardly been concerned, which are usually treated as impurities. Here, it is observed that after simple washing with water and ethanol, GDY still contains a certain amount of copper ions, and demonstrated that the copper ions are adsorbed at the atomic layers of GDY. Furthermore, we transformed in situ the copper ions into ultrathin Cu nanocrystals, and the obtained Cu/GDY hybrids can be generally converted into a series of metal/GDY hybrid materials, such as Ag/GDY, Au/GDY, Pt/GDY, Pd/GDY, and Rh/GDY. The Cu/GDY hybrids exhibit extraordinary surface enhanced Raman scattering effect and can be applied in pollutant efficient enrichment and detection. [ABSTRACT FROM AUTHOR]

A general polymerization‐induced strategy is developed to synthesize large‐area (100 cm2) transition metal nitride (TMN: TiN, MoN, WN, VN) porous arrays with high specific surface area (187.5–215.5 m2 g−1) for the first time, which also can be used to prepare TMN porous arrays uniformly doped with multiple elements. The formation of homogeneous organic/inorganic hybrid polymer precursors is a key factor in forming such TMN porous arrays. The TiN porous arrays exhibit an intense blue‐light localized surface plasmon resonance effect centered at 508 nm. The TiN porous arrays also show a remarkable surface‐enhanced Raman scattering (SERS) effect with a Raman enhanced factor of 5.7 × 107 and the lowest detection limit of 1.0 × 10−12 m. They show ultrahigh corrosion resistance and oxidation resistance, which are not available on traditional noble metal and semiconductor SERS substrates. These results suggest the possibility of the development of effective SERS substrates by using cheap TiN to replace the expensive commercial Au substrates. [ABSTRACT FROM AUTHOR]

Except for conventional functions, special textiles doped with nanoscale particles have shown quite attractive properties, such as antibacterial activity, deodorization, hydrophobicity, and ultraviolet/electromagnetic protection. However, facile and reliable methods for quality assessment of those functional nano-textiles are remarkably demanded for market surveillance and consumer protection. Herein, a novel detection method of silver in textiles was established for the comprehensive detection and a practical flow chart was also demonstrated as an experimental pathway including pretreatment, qualitative and quantitative analysis. The optimal ashing parameter (450°C for 1 h) in the pretreatment process was explored to improve detection sensitivity. The qualitative analysis was performed through X-ray diffraction for crystallinity, scanning electron microscopy for morphology, and energy-dispersive X-ray spectroscopy (EDS) for elements. The real existent status of the silver components could be decided via the flow chart. As shown with the detected sample, the content was calculated by the weight loss at 1050–1500°C from thermogravimetric analysis measurement and the accuracy of the quantitative process was also checked via inductively coupled plasma mass spectrometry. Finally, the detection limit of the method was investigated up to μg/g. The obvious advantage of the reported method was facile and reliable to achieve comprehensive identification from the dimension scale and crystal form to the component. Moreover, this analytical strategy could be also applied for the detection of other nanoscale metals or metal oxides in functional textiles. [ABSTRACT FROM AUTHOR]

Abstract Background The syndrome is the basic pathological unit and the key concept in traditional Chinese medicine (TCM) and the herbal remedy is prescribed according to the syndrome a patient catches. Nevertheless, few studies are dedicated to investigate the number of syndromes and what these syndromes are. Correlative measure based on mutual information can measure arbitrary statistical dependences between discrete and continuous variables. Results We presented a revised version of mutual information to discriminate positive and negative association. The entropy partition method self-organizedly discovers the effective patterns in patient data and rat data. The super-additivity of cluster by mutual information is proved and N-class association concept is introduced in our model to reduce computational complexity. Validation of the algorithm is performed by using the patient data and its diagnostic data. The partition results of patient data indicate that the algorithm achieves a high sensitivity with 96.48% and each classified pattern is of clinical significance. The partition results of rat data show the inherent relationship between vascular endothelial function related parameters and neuro-endocrine-immune (NEI) network related parameters. Conclusion Therefore, we conclude that the algorithm provides an excellent solution to patients and rats data problem in the context of traditional Chinese medicine.

Surface‐enhanced Raman scattering (SERS) spectroscopy has renowned its fame for the ultra‐high sensitivity and single‐molecule detection ability, and listed as a fingerprint spectrum representative in various trace detection fields. Considerable efforts have been made by researchers to design high‐sensitive SERS‐active substrates ranging from noble metals to semiconductors. This review summarizes the fundamental theories for SERS technique, that is, the electromagnetic enhancement mechanism and chemical enhancement mechanism and the state‐of‐the‐art design strategies for noble metal and semiconductor substrates. It also sheds light on the effective approaches to improve the SERS activity for noble metal substrates, that is, tuning the localized surface plasmon resonance position, the assembling of hot spots, and precise controlling of nanogaps. Although charge transfer is considered as the main reason for the enhancement mechanism for semiconductors at the present stage, the underlying theoretical basis remains mysterious. This review summarized the critical points for SERS‐active substrates design and prospected the future development direction of SERS technology. [ABSTRACT FROM AUTHOR]

Structure and size control are always considered to be effective routes to enhance the sensitivity of materials. Herein, rough VO2 (D) nanostars and nanospheres with highly dense and rough surfaces were synthesized. Accompanied by the properties inherited from the rough VO2 nanospheres, i.e. , high adsorption and strong plasma resonance, these VO2 (D) nanospheres exhibit highly sensitive activity as a surface enhanced Raman spectrum substrate. The detection limit of Rhodamine 6G on this semiconductor SERS substrate is as low as 10−9 M. [ABSTRACT FROM AUTHOR]