Study on Ultrathin Silver Film Transparent Electrodes Based on Aluminum Seed Layers with Different Structures.

Ag has the lowest electrical resistivity among all metals, and at the same time, the best optical properties in the visible and near-IR spectral range; it is therefore the most widely employed material for thin-metal-film-based transparent conductors. In this work, an ultra-thin transparent silver film electrode with aluminum as seed layer was prepared by a resistive thermal evaporation technique. Using a range of electrical, optical and surface morphology techniques, it can be noted that the presence of the thin layer of aluminum changes the growth kinetics (nucleation and evolution) of the thermal evaporation of Ag, leading to silver films with smooth surface morphology and high electrical conductivity, and the threshold thickness of the silver film is reduced. It is inferred that the aluminum layer showed a good infiltration effect on the ultra-thin silver film, by analyzing the transmittance spectrum, sheet resistance and surface morphology. Moreover, the average transmittance of silver film with 10 nm is 40% in the 400-2500 nm band, whereas the sheet resistance is 13 Ωsq -1. A series of experiments show that the introduction of Al seed layer has certain effect on improving the properties of transparent conductive silver films. Then, a new method for deposition of 1 nm Al seed layer was proposed; that is, the 1 nm aluminum infiltrated layer is divided into two or more layers, and the average transmittance of silver film with 5 nm is 60% in the 400-2500 nm band, whereas the sheet resistance does not exceed 100 Ω sq-1.

Observation of robust zero-energy state and enhanced superconducting gap in a trilayer heterostructure of MnTe/Bi2Te3/Fe(Te, Se).

The interface between magnetic material and superconductors has long been predicted to host unconventional superconductivity, such as spin-triplet pairing and topological nontrivial pairing state, particularly when spin-orbital coupling (SOC) is incorporated. To identify these unconventional pairing states, fabricating homogenous heterostructures that contain such various properties are preferred but often challenging. Here, we synthesized a trilayer-type van der Waals heterostructure of MnTe/Bi2Te3/Fe(Te, Se), which combined s-wave superconductivity, thickness-dependent magnetism, and strong SOC. Via low-temperature scanning tunneling microscopy, we observed robust zero-energy states with notably nontrivial properties and an enhanced superconducting gap size on single unit cell (UC) MnTe surface. In contrast, no zero-energy state was observed on 2-UC MnTe. First-principle calculations further suggest that the 1-UC MnTe has large interfacial Dzyaloshinskii-Moriya interaction and a frustrated AFM state, which could promote noncolinear spin textures. It thus provides a promising platform for exploring topological nontrivial superconductivity.

Performance Enhancement of Silver Nanowire-Based Transparent Electrodes by Ultraviolet Irradiation.

Silver nanowires (AgNWs) are used as transparent electrodes (TE) in many devices. However, the contact mode between the nanowires is the biggest reason why the sheet resistance of silver nanowires is limited. Here, simple and effective ultraviolet (UV) irradiation welding is chosen to solve this problem. The influence of the power density of the UV irradiation on welding of the silver nanowires is studied and the fixed irradiation time is chosen as one minute. The range of the UV (380 nm) irradiation power is chosen from 30 mW/cm2 to 150 mW/cm2. First of all, the transmittance of the silver nanowire film is not found to be affected by the UV welding (400-11,000 nm). The sheet resistance of the silver nanowires decreases to 73.9% at 60 mW/cm2 and increases to 127.6% at 120 mW/cm2. The investigations on the UV irradiation time reveal that the sheet resistance of the AgNWs decreases continuously when the UV irradiation time is varied from 0 to 3 min, and drops to 57.3% of the initial value at 3 min. From 3-6 min of the continuous irradiation time, the change of the sheet resistance is not obvious, which reflects the self-limiting and self-termination of AgNWs welding. By changing the wavelength of the UV irradiation from 350-400 nm, it is found that the welding effect is best when the UV wavelength is 380 nm. The average transmittance, square resistance, and the figure of merit of the welded AgNWs at 400-780 nm are 95.98%, 56.5 Ω/sq, and 117.42 × 10-4 Ω-1, respectively. The UV-welded AgNWs are also used in silicon-based photodetectors, and the quantum efficiency of the device is improved obviously.

Simultaneous determination of serum homocysteine, cysteine, and methionine in patients with schizophrenia by liquid chromatography-tandem mass spectrometry.

Schizophrenia is a debilitating psychiatric disorder affecting approximately 1% of the population worldwide. Disturbances in the homocysteine metabolism are an important factor in the pathophysiology of schizophrenia. In this research, a novel validated liquid chromatography-tandem mass spectrometry (LC-MS/MS) quantification procedure was developed to investigate three significant compounds of homocysteine metabolism: homocysteine, cysteine, and methionine in patients with schizophrenia and healthy controls. Sample preparation involved a reduction with dithiothreitol followed by protein precipitation, and the chromatographic runtime was 2 min. The LC-MS/MS method was validated according to CLSI C62-A and the Chinese Guidance for Liquid Chromatography and Mass Spectrometry Clinical Application. The performance of the method was excellent with a coefficient of variation for precision in the range of 0.5-6.9%, an accuracy of 90.4-101.6%. In addition, the practical applicability of the method was demonstrated by applying it in the routine sample analysis for a schizophrenic patient. Increased homocysteine levels and decreased cysteine levels were observed in the patient with schizophrenia. These results indicate that the activity of the transsulfuration pathway may play a key role in the pathogenesis of schizophrenia.

Biomagnification and enantiomeric profiles of organochlorine pesticides in food web components from Zhoushan Fishing Ground, China.

Trophodynamics and chiral signatures of organochlorine pesticides (OCPs), including dichlorodiphenyltrichloroethanes (DDTs), hexachlorocyclohexanes (HCHs), and chlordanes in a food web from Zhoushan Fishing Ground, China, were studied. Residues of OCPs in all teleost fishes were within food safety levels. Strong positive correlations were found between trophic levels (TLs) and wet weight concentrations of target chemicals, with trophic magnification factors (TMFs) from 4.17 to 9.77. Lipid contents and TLs significantly correlated, which indirectly affect the bioaccumulation processes of OCPs. The consistently racemic EF values of α-HCH, as well as invariability of the relative proportions of HCH isomers in different marine species implied that HCHs in animals originate directly from the surrounding environment. However, in vivo biotransformation and/or elimination of o,p'-DDT cannot be precluded. TMFs of the individual enantiomers further suggest that the influence of achiral biotransformation is too minor to induce enantioselective biomagnification of chiral OCPs through the studied food web.

Spatial distribution and implications to sources of halogenated flame retardants in riverine sediments of Taizhou, an intense e-waste recycling area in eastern China.

Concentrations and spatial distribution pattern of organohalogen flame retardants were investigated in the riverine surface sediments from Taizhou, an intensive e-waste recycling region in China. The analytes were syn- and anti- Dechlorane Plus (DP), Dechloranes 602, 603, and 604, a DP monoadduct, two dechlorinated DPs and 8 congeners of polybrominated diphenyl ethers (PBDEs). The concentrations of Σ8PBDEs, ΣDP, ΣDec600s, and ΣDP-degradates ranged from <100 to 172,000, 100 to 55,000, not detectable (nd) to 1600, and nd to 2800 pg/g dry weight, respectively. BDE-209 and DP, both have been manufactured in China, had similar spatial distribution patterns in the study area, featured by distinctly recognizable hotspots some of which are in proximity to known e-waste dumping or metal recycling facilities. Such patterns were largely shared by Dec602 and dechlorinated DP, although their concentration levels were much lower. These major flame retardants significantly correlate with each other, and cluster together in the loading plot of principle component analysis. In contrast, most non-deca PBDE congeners do not correlate with DPs. Dec604 stood out having distinctly different spatial distribution pattern, which could be linked to historical use of mirex. Organic matter content of the sediment was not the dominant factor in determining the spatial pattern of pollution by halogenated flame retardants in the rivers of this study.

[Inhibition of sciadopitysin against UDP-glucuronosyltransferases].

This study was designed to investigate the inhibitory effects of sciadopitysin on the catalytic activities of human 12 kinds of UDP-glucuronosyltransferases (UGTs) in vitro. The risk of drug-drug interactions (DDI) is predicted by in vitro-in vivo extrapolation (IV-IVE). Methods A panel of recombinant human UGT isoforms and human liver microsome (HLM) as well as a series substrates including 4-methyl umbelliferone (4-MU), trifluoperazine (TFP) and N-3-carboxypropyl-4-hydroxy-1, 8-naphthalimide (NCHN) (UGT1A1 specific fluorescent probe substrates） were used to characterize the inhibitory effects of sciadopitysin on human UGTs in vitro. The half maximum inhibitory concentration (IC(50)) and the constant of inhibition kinetics (K(I)) were obtained by nonlinear regression using GraphPad Prism 6.0 software. The potential risk of DDI induced by UGT1A1 was predicted based on in vitro parameters. The results demonstrated that sciadopitysin had strong inhibitory effects on UGT1A1, UGT1A3, UGT1A8 and UGT1A10, with the remaining activity being below 30% at a final concentration of 10 µmol·L(-1). For UGT1A1, UGT1A3, UGT1A8 and UGT1A10, the IC(50) was 0.20 µmol·L(-1) to 1.34 µmol·L(-1), the inhibition kinetic constant K(I) was 0.07 µmol·L(-1) to 2.12 µmol·L(-1). The AUC ratio of UGT1A1 can be increased by 19% to 147% at the oral dose of 240 mg·d(-1). The sciadopitysin competitively inhibited the formation of 4-MU-O-glucuronide by UGT1A1, UGT1A3, UGT1A8, and UGT1A10. At the same time, the inhibition of NCHN-O-glucuronidation by UGT1A1 was consistent with the competitive inhibition. The strong inhibition of sciadopitysin on UGT1A1 led to reduction of the metabolism of UGT1A1 substrates, and increased the risk of DDI. When co-administrated with other drugs, special attentions should be given to the DDI from inhibition of drug metabolism enzymes to prevent serious clinical consequences.

[Determination of the eliminating ratio of TCM polysaccharide to hydroxyl radical by kinetic fluorescent spectrophotometry].

OBJECTIVE: To explore reaction dynamic of hydroxyl radical (*OH) and salicylic acid,and to determine the elimination ratios of TCM polysaccharide to *OH by kinetic fluorescent analysis. METHODS: The impact dynamics factors of this reaction were studied by fluorescent, such as the reaction of concentration, reaction time and temperature. The dynamical equation was built, a kinetic fluorescent spectrophotometry based on the reaction was developed to determine the elimination ratio. Repetitiveness and reliability of this method were tested by vitamin C. RESULTS: The dynamical equation of reaction rate to salicylic acid was gamma = 0. 9818x -1. 1801 under the condition of lambda ex = 295 nm, lambda em = 411 nm at room temperature, r approximately 1. The 50% elimination ratio (IC50) of TCM polysaccharide of Tangerine peel and Ganoderma lucidum to *OH was 78.01 mg/L and 232.5 mg/L, respectively. The IC50 of vitamin C was 24.52 microg/L, RSD was 0.23% (n = 5). CONCLUSIONS: The method is sensitive and reliable, it can be used to determine the elimination ratio of TCM polysaccharide to *OH.