[A new idea for studying processing mechanism based on formation of supramolecular aggregates in traditional Chinese medicine decoctions].

Traditional Chinese medicines must be processed into decoction pieces before they can be used medicinally, and decoctions are the most common dosage form in TCM. Recent studies have shown that these decoctions are complex multiphase disperse systems containing supramolecular aggregates. These aggregates form through self-assembly interactions among chemical components du-ring the decocting process, in which hydrogen bonding, π-π interactions, van der Waals' forces, and hydrophobic interactions playing crucial roles.

Single-molecule detection of SARS-CoV-2 N protein on multilayered plasmonic nanotraps with surface-enhanced Raman spectroscopy.

The spread of the SARS-CoV-2 virus has had an unprecedented impact, both by posing a serious risk to human health and by amplifying the burden on the global economy. The rapid identification of the SARS-CoV-2 virus has been crucial to preventing and controlling the spread of SARS-CoV-2 infections. In this study, we propose a multilayered plasmonic nanotrap (MPNT) device for the rapid identification of single particles of SARS-CoV-2 virus in ultra-high sensitivity by surface-enhanced Raman scattering (SERS).

A comprehensive SERS, SEM and EDX study of individual atmospheric PM particles in Chengdu, China.

Characterization of atmospheric fine particulate matter (PM) in large cities has important implications for the study of their sources and formation mechanisms, as well as in developing effective measures to control air pollution. Herein, we report a holistic physical and chemical characterization of PM by combining surface-enhanced Raman scattering (SERS) with scanning electron microscopy (SEM) and electron-induced X-ray spectroscopy (EDX). PM particles were collected in a suburban area of Chengdu, a large city in China with a population over 21 million.

Identification and classification of particle contaminants on photomasks based on individual-particle Raman scattering spectra and SEM images.

Particle contamination of photo masks is a significant issue facing the micro-nanofabrication process. It is necessary to analyze the particulate matter so that the contamination can be effectively controlled and eliminated. In this study, Raman spectroscopy was used in combination with scanning electron microscopy with energy analysis (SEM-EDX) techniques to study the contamination of individual particles on the photomask.

Surface-enhanced Raman Scattering of Au-Ag bimetallic nanopillars fabricated using surface-plasmon lithography.

Arrays of gold-silver (Au-Ag) bimetallic nanopillars were fabricated by a newly developed surface-plasmon lithography (SPL) and their enhancement properties as surface-enhanced Raman scattering (SERS) substrates have been studied. We demonstrated that the SPL is a low-cost and high efficiency method for the fabrication of SERS substrates with both high sensitivity and reproducibility. The nanopillars showed a good response in the detection of methylene blue molecules at a low concentration of 1.

Surface-enhanced Raman scattering with gold-coated silicon nanopillars arrays: The influence of size and spatial order.

Nanopillars have been extensively explored as promising substrates for surface-enhanced Raman scattering (SERS) owing to their high sensitivity and excellent reproducibility. Most of the researches have been focused on the fabrication methods of nanopillars, and the dependences of SERS effects on geometrical size and spatial order are rarely investigated. In this work, SERS properties of nanopillars with different sizes (115-185 nm) and spatial orders (square and rhombus orders) have been studied.

Multiple-resonant pad-rod nanoantennas for surface-enhanced infrared absorption spectroscopy.

Due to the ability to tightly confine electromagnetic energy, plasmonic nanoantennas have been widely studied for surface-enhanced infrared absorption (SEIRA) spectroscopy, surface-enhanced Raman spectroscopy as well as refractive index sensing. However, most of the nanoantennas are limited by narrow resonant band and it is rather challenging to detect multiple molecular fingerprints. In this work, we report dual and triple- resonant pad-rod plasmonic nanoantennas which are nanorods with large pads at their ends placed above gold (Au) mirror separated by a spacer layer.

Large-Scale, Bandwidth-Adjustable, Visible Absorbers by Evaporation and Annealing Process.

Optical absorbers have received a significant amount of attention due to their wide range of applications in biomedical sensing, solar cell, photon detection, and surface-enhanced Raman spectroscopy. However, most of the optical absorbers are fabricated with high-cost sophisticated nanofabrication techniques, which limit their practical applications. Here, we introduce a cost-effective method to fabricate an optical absorber by using a simple evaporation technique.

High optical transmittance of aluminum ultrathin film with hexagonal nanohole arrays as transparent electrode.

We fabricate samples of aluminum ultrathin films with hexagonal nanohole arrays and characterize the transmission performance. High optical transmittance larger than 60% over a broad wavelength range from 430 nm to 750 nm is attained experimentally. The Fano-type resonance of the excited surface plasmon plaritons and the directly transmitted light attribute to both of the broadband transmission enhancement and the transmission suppression dips.

Resonance control of mid-infrared metamaterials using arrays of split-ring resonator pairs.

We present our design, fabrication and characterization of resonance-controllable metamaterials operating at mid-infrared wavelengths. The metamaterials are composed of pairs of back-to-back or face-to-face U-shape split-ring resonators (SRRs). Transmission spectra of the metamaterials are measured using Fourier-transform infrared spectroscopy.

Anomalous Surface Wave Launching by Handedness Phase Control.

Anomalous launch of a surface wave with different handedness phase control is achieved in a terahertz metasurface based on phase discontinuities. The polarity of the phase profile of the surface waves is found to be strongly correlated to the polarization handedness, promising polarization-controllable wavefront shaping, polarization sensing, and environmental refractive-index sensing.

Integrating carbon nanotubes into silicon by means of vertical carbon nanotube field-effect transistors.

Single-walled carbon nanotubes have been integrated into silicon for use in vertical carbon nanotube field-effect transistors (CNTFETs). A unique feature of these devices is that a silicon substrate and a metal contact are used as the source and drain for the vertical transistors, respectively. These CNTFETs show very different characteristics from those fabricated with two metal contacts.

Enhanced extraordinary optical transmission (EOT) through arrays of bridged nanohole pairs and their sensing applications.

Extraordinary optical transmission (EOT) through arrays of gold nanoholes was studied with light across the visible to the near-infrared spectrum. The EOT effect was found to be improved by bridging pairs of nanoholes due to the concentration of the electromagnetic field in the slit between the holes. The geometrical shape and separation of the holes in these pairs of nanoholes affected the intensity of the transmission and the wavelength of resonance.

Extraordinary mid-infrared transmission of subwavelength holes in gold films.

Gold (Au) nanoholes are fabricated with electron-beam lithography and used for the investigation of extraordinary transmission in mid-infrared regime. Transmission properties of the nanoholes are studied as the dependence on hole-size. Transmittance spectra are characterized by Fourier transform infrared spectroscopy (FTIR) and enhanced transmittance through the subwavelength holes is observed.

Real time hybridization studies by resonant waveguide gratings using nanopattern imaging for Single Nucleotide Polymorphism detection.

2D imaging of biochips is particularly interesting for multiplex biosensing. Resonant properties allow label-free detection using the change of refractive index at the chip surface. We demonstrate a new principle of Scanning Of Resonance on Chip by Imaging (SORCI) based on spatial profiles of nanopatterns of resonant waveguide gratings (RWGs) and its embodiment in a fluidic chip for real-time biological studies.

Bending-induced electromechanical coupling and large piezoelectric response in a micromachined diaphragm.

We investigated the dependence of electromechanical coupling and the piezoelectric response of a micromachined Pb(Zr₀.₅₂Ti₀.₄₈)O₃ (PZT) diaphragm on its curvature by observing the impedance spectrum and central deflection responses to a small AC voltage.

Broadband terahertz wave deflection based on C-shape complex metamaterials with phase discontinuities.

A broadband terahertz wave deflector based on metasurface induced phase discontinuities is reported. Various frequency components ranging from 0.43 to 1.

Broadband plasmon induced transparency in terahertz metamaterials.

Plasmon induced transparency (PIT) could be realized in metamaterials via interference between different resonance modes. Within the sharp transparency window, the high dispersion of the medium may lead to remarkable slow light phenomena and an enhanced nonlinear effect. However, the transparency mode is normally localized in a narrow frequency band, which thus restricts many of its applications.

Surface-enhanced Raman scattering on gold nanotrenches and nanoholes.

Dependent effects on edge-to-edge distance and incidence polarization in surface-enhanced Raman Scattering (SERS) were studied in detection of 4-mercaptopyridine (4-MPy) molecules absorbed on gold nanotrenches and nanoholes. The gold nanostructures with controllable size and period were fabricated using electron-beam lithography. Large SERS enhancement in detection of 4-MPy molecules on both nanostructred substrates was observed.

Fabrication of metallic nanostructures of sub-20 nm with an optimized process of E-beam lithography and lift-off.

A process consisting of e-beam lithography and lift-off was optimized to fabricate metallic nanostructures. This optimized process successfully produced gold and aluminum nanostructures with features size less than 20 nm. These structures range from simple parallel lines to complex photonic structures.

Detecting small lung tumors in mouse models by refractive-index microradiology.

Refractive-index (phase-contrast) radiology was able to detect lung tumors less than 1 mm in live mice. Significant micromorphology differences were observed in the microradiographs between normal, inflamed, and lung cancer tissues. This was made possible by the high phase contrast and by the fast image taking that reduces the motion blur.

Morphological study of early-stage lung cancer using synchrotron radiation.

In the present study the feasibility of applying synchrotron radiation to the morphological study of early-stage lung cancer has been investigated. Lewis lung cancer was implanted and grown in a nude mouse for different periods, and imaged using phase-contrast synchrotron X-rays. Morphological differences were clearly shown between the normal lung and cancerous tissues at this early stage.

[Comprehensive study of lead pollution in atmospheric aerosol of Shanghai].

The lead contamination, lead species and source assignment were studied by a combination of several analytical techniques such as Proton-induced X-ray emission analysis (PIXE), Proton microprobe (micro-PIXE), Inductively coupled plasma-mass spectrometry (ICP-MS) and extended X-ray absorption fine structure (EXAFS) techniques. The results indicate that the lead concentration in the air of Shanghai gradually decreased over the last years. The atmospheric lead concentration of PM10 in the winter of 2002 was 369 ng x m(-3), which had declined by 28% in 2001, and in the winter of 2003 it decreased further to 237 ng x m(-3).

Origins of PM10 determined by the micro-proton induced X-ray emission spectra of single aerosol particles.

The micro-proton induced X-ray emission (micro-PIXE) spectrum of a single aerosol particle (SAP) was considered as its fingerprint for tracing its origin. A proton microprobe was used to extract fingerprints of SAPs. Environmental monitoring samples of PM(10) were collected from a heavy industrial area of Shanghai and were analyzed by proton microprobe for finding their pollution sources.