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Silver film over nanospheres (AgFON) have been prepared by depositing Ag thin film onto the self-assembled monolayer arrays of polystyrene nanospheres with vacuum magnetron sputtering method. The surface morphologies and optical properties have been characterized by using scanning electron microscope (SEM) and ultraviolet-visible near-infrared (UV-Vis-NIR) spectrophotometer. AgFON was used as substrate to detect the surface-enhanced Raman scattering (SERS) spectra of malachite green (MG) and melamine (MA). It was found that the AgFON substrate presented outstanding performance that the Raman enhancement factor was calculated to be as large as 9.76 × 1012. The minimum limit for MG was down to 10−8 mol/L with a good linear response range from 10−4 to 10−8 mol/L. In addition, this substrate showed excellent ability to recognize MA molecules with a detection limit of 0.1 mg/L. A good linearity (r = 0.9887) was obtained in the concentration range of 2–100 mg/L. Furthermore, the AgFON substrate exhibited good uniformity with a relative standard deviation (RSD) of 9.01 % and good reproducibility with RSD of 8.60 %.

Gold (Au) nanocap arrays and hollow gold nanocap particles were prepared by dip-coating technique combined with wet chemical reduction method, and followed by sonication and dissolution of the silica colloidal template. The surface morphologies and optical properties of the obtained samples were characterized by scanning electron microscopy, transmission electron microscope, and ultraviolet-visible spectrophotometer, respectively. Gold nanocap arrays and hollow gold nanocap particles were used as substrates to detect the surface-enhanced Raman scattering spectra of malachite green and methylene blue (MB), respectively. It was found that the gold nanocap arrays had higher enhancement ability than hollow gold nanocap particles, with enhancement factor of 1.3 × 105 and 3.5 × 103, respectively. In addition, gold nanocap arrays exhibited excellent reproducibility with a relative standard deviation of less than 5% and about 10% across a single substrate and between different substrates, respectively. Th...

Chemically synthetic nanomotors can consume fuel in the environment and utilize the self-generated concentration gradient to self-propel themselves in the system. We study the collective dynamics of an ensemble of sphere dimers built from linked catalytic and noncatalytic monomers. Because of the confinement from the fuel field and the interactions among motors, the ensemble of dimer motors can self-organize into various nanostructures, such as a radial pattern in the spherical fuel field and a staggered radial pattern in a cylindrical fuel field. The influence of the dimer volume fraction on the self-assembly is also investigated and the formed nanostructures are analyzed in detail. The results presented here may give insight into the application of the self-assembly of active materials.

Colloidal silver nanoparticles were prepared by a simple chemical reduction method. The effect of L-cysteine on the surface-enhanced Raman scattering activity of colloidal silver nanoparticles was investigated by using malachite green as a probe molecule. It was found that the surface-enhanced Raman scattering activity of colloidal silver nanoparticles was improved tremendously with the help of L-cysteine. The possible reasons for this enhancement effect were given. Specifically, in silver colloidal solution, no surface-enhanced Raman scattering spectrum of malachite green was observed at a relatively low concentration (≤2.5 × 10−5 mol/L). However, well-resolved and high-quality surface-enhanced Raman scattering spectra of malachite green were successfully obtained after the addition of L-cysteine to silver colloids, and the minimum detection limit for malachite green was down to 10−8 mol/L.

Bismuth nanocap arrays have been prepared by vacuum depositing Bi films onto the surfaces of self-assembled monolayer arrays of SiO2 nanoparticles. The surface morphologies, structures, and optical properties of the obtained samples have been characterized by transmission electron microscopy (TEM), scanning electron microscopy (SEM), atomic force microscope (AFM), X-ray diffraction (XRD), and ultraviolet–visible–near infrared (UV–vis–NIR) spectrophotometer. TEM and AFM images indicated that the SiO2/Bi composite nanoparticles were incompletely encapsulated and their surfaces were relatively rough. UV–vis–NIR absorption spectra showed that Bi nanocap arrays had strong and tunable surface plasmon resonance peaks in the visible and near infrared regions, which were dependent dramatically on the relative ratio of the SiO2 core diameter to the Bi cap thickness.

Copper nanocap arrays, consisting of a SiO 2 core with a Cu cap, were prepared by chemical synthesis combined with physical evaporation technique. The obtained samples were characterized by scanning electron microscopy, atomic force microscopy, X-ray diffraction, and ultraviolet-visible-near-infrared spectrophotometer. The copper nanocap arrays were found to exhibit tunable surface plasmon resonance (SPR) absorption peaks that were red-shifted as the ratio of the SiO 2 core diameter to the Cu cap thickness increased. While the cap thickness varied between 20 nm and 50 nm, the SPR peak shifted from 1650 nm to 1230 nm. While the core diameter varied between 140 nm and 400 nm, the longitudinal SPR peak shifted from 1243 nm to 1830 nm.

Hepatitis B virus (HBV)‐associated nephropathy is not a rare manifestation of HBV infection; this could result in diagnostic confusion and the possible misidentification of a diabetic patient with albuminuria. We present the first published case of a HBV‐associated nephropathy occurring in a patient with diabetes. The patient was a 24‐year‐old man who was admitted to hospital with 4 days of generalized swelling and oliguria. He had a 3‐year history of weight loss, and a 1‐year history of polydipsia and polyuria before the symptoms of generalized swelling and oliguria appeared. Laboratory tests showed a fasting blood sugar of 15.1 mmol/L and glycated hemoglobin of 18.1%. The 24‐h urine protein excretion was 2807.8 mg and serum albumin was 19.1 g/L. The diagnosis of HBV‐associated nephropathy was confirmed by serological evaluations of HBV antigen and antibodies, immunohistochemical evidence of HBV‐related antigens, and immune complexes in renal biopsies. The decreased proteinuria was observed after antiviral therapy.

Two Mn+–2-(5-bromo-2-pyridylazo)-5-diethylaminophenol systems for the simultaneous determination of the valence states of Cr and Fe using factor analysis were studied. (1) At pH 4.0, CrIII and CrVI react with the reagent to form stable complexes and a slight difference in the wavelengths of maximum absorption (λmax.) between the two complexes is observed when the sodium lauryl sulfate, which also acts as a solubilizing and sensitizing agent, is added, viz., 590 nm for CrIII and 593 nm for CrVI complexes. (2) In the presence of ethanol, both FeII and FeIII form 1:2 complexes with the reagent at pH 2.5–3.5 and the λmax. of the FeII and FeIII complexes is at 557 and 592 nm, respectively. In the target transformation factor analysis, the K coefficients calculated from the standard mixtures by classical least-squares analysis and a non-zero intercept added to each wavelength are used as the target vector instead of the pure component standards; this can decrease the analysis errors introduced by the interaction between the two species and by deviations from Beer's law.