Study on synergistic pyrolysis and kinetics of mixed plastics based on spent fluid-catalytic-cracking catalyst.

At present, disposable plastic products such as plastic packaging are very common in our daily life. These products are extremely easy to cause serious damage to the soil and marine environment due to their short design and service life, difficulties in degradation, or long degradation cycles. Thermochemical method (pyrolysis or catalytic pyrolysis) is an efficient and environmentally friendly way to treat plastic waste. In order to further reduce the energy consumption of plastic pyrolysis and improve the recycling rate of spent fluid catalytic cracking (FCC) catalysts, we adopt the "waste-to-waste" approach to apply the spent FCC catalysts as catalysts in the catalytic pyrolysis of plastics, exploring the pyrolysis characteristics, kinetic parameters, and synergistic effects between different typical plastics (polypropylene, low-density polyethylene, polystyrene). The experimental results show that the spent FCC catalysts used in the catalytic pyrolysis of plastics are beneficial to reduce the overall pyrolysis temperature and activation energy, in which the maximum weight loss temperature decreases by about 12 â„ƒ and the activation energy decreases by about 13%. The activity of spent FCC catalysts is improved after modification by microwave and ultrasonic, which further improve the catalytic efficiency and reduce the energy consumption of pyrolysis. The co-pyrolysis of mixed plastics is dominated by positive synergistic effect, which is conducive to improving the thermal degradation rate and shortening the pyrolysis time. This study provides relevant theoretical support for the resource application of spent FCC catalysts and "waste-to-waste" treatment of plastic waste.

Dry Lithography Patterning of Monolayer Flexible Field Effect Transistors by 2D Mica Stamping.

Organic field-effect transistors (OFETs) based on 2D monolayer organic semiconductors (OSC) have demonstrated promising potentials for various applications, such as light emitting diode (LED) display drivers, logic circuits, and wearable electrocardiography (ECG) sensors. To date, the fabrications of this class of highly crystallized 2D organic semiconductors (OSC) are dominated by solution shearing. As these organic active layers are only a few molecular layers thick, their compatibilities with conventional thermal evaporated top electrodes or sophisticated photolithography patterning are very limited, which also restricts their device density. Here, an electrode transfer stamp and a semiconductor patterning stamp are developed to fabricate OFETs with channel lengths down to 3 µm over a large area without using any chemicals or causing any damage to the active layer. 2D 2,9-didecyldinaphtho[2,3-b:2',3'-f]thieno[3,2-b]thiophene (C10 -DNTT) monolayer OFETs developed by this new approach shows decent performance properties with a low threshold voltage (VTH ) less than 0.5 V, intrinsic mobility higher than 10 cm2 V-1 s-1 and a subthreshold swing (SS) less than 100 mV dec-1 . The proposed patterning approach is completely comparable with ultraflexible parylene substrate less than 2 µm thick. By further reducing the channel length down to 2 µm and using the monolayer OFET in an AC/DC rectifying circuit, the measured cutoff frequency is up to 17.3 MHz with an input voltage of 4 V. The newly proposed electrode transfer and patterning stamps have addressed the long-lasting compatibility problem of depositing electrodes onto 2D organic monolayer and the semiconductor patterning. It opens a new path to reduce the fabrication cost and simplify the manufacturing process of high-density OFETs for more advanced electronic or biomedical applications.

Sternheimer-Malbin Staining to Detect Decoy Cells in Urine of 213 Kidney Transplant Patients.

BACKGROUND: Human polyoma virus-associated nephropathy frequently refers to allograft failure after kidney transplant. Thus, the early detection of viral activation is extremely important for these immunocompromised patients. METHODS: Previously, urine polyoma virus-infected cells (decoy cells) were indicated as the virus action, usually screened by the routine papanicolaou cytology in renal biopsy, but these methods are complex and the positive rate is low. In this article, the direct microscopy observation method, Wright-Giemsa staining, and Sternheimer-Malbin (SM) staining were all used to screen the decoy cells in urine samples of 213 kidney transplant patients who had used immunosuppressive drugs. RESULTS: Among them, decoy cells were detected in 40 cases (18.8%) by the direct observation method, 44 cases (20.7%) by Wright-Giemsa staining and 49 cases (23.0%) by SM staining. Furthermore, the most common polyoma viruses, BK and JC viruses, were also confirmed in 41 (83.7%) cases among these 49 decoy cell-positive samples. Importantly, compared with other decoy cell detection methods, SM staining is fast, easy to operate, and has a high positive rate. CONCLUSION: Therefore, SM staining is recommended as a fast and effective method for screening urine decoy cells in kidney transplant patients.

Enhanced Detectivity and Suppressed Dark Current of Perovskite-InGaZnO Phototransistor via a PCBM Interlayer.

Hybrid phototransistors based on InGaZnO (IGZO) metal oxide thin-film transistors (TFT) and a photoabsorbing capping layer such as perovskite (MAPbI3) are a promising low-cost device for developing advanced X-ray and UV flat-panel imagers. However, it is found that the introduction of MAPbI3 inevitably damages the IGZO channel layer during fabrication, leading to deteriorated TFT characteristics such as off-current rising and threshold voltage shift. Here, we report an effective approach for improving the performance of the perovskite-IGZO phototransistor by inserting a [6,6]-phenyl C61-butyric acid methyl ester (PCBM) or PCBM:PMMA interlayer between the patterned MAPbI3 and IGZO. The interlayer effectively prevents the IGZO from damage by the perovskite fabrication process, while allowing efficient charge transfer for photosensing. In this configuration, we have achieved a high-detectivity (1.35 × 1012 Jones) perovskite-IGZO phototransistor with suppressed off-state drain current (∼10 pA) in the dark. This work points out the importance of interface engineering for realizing higher performance and reliable heterogeneous phototransistors.

[HPLC-TOF-MS analysis of metabolites of Diffusa effective extracts in rats].

OBJECTIVE: To analyze p-coumaril acid, trans-6-O-p-coumaroyl scandoside methyl ester and its metabolites in rat plasma after intragastric administration of exocarpium Diffusa effective extracts. METHOD: Rat blood samples were collected 1.0 h after oral administration of 0.4 g x kg(-1) exocarpium Diffusa effective extracts, and then were analyzed by using HPLC-Q-TOF-MS. RESULT: In rat plasma, only one metabolite was detected. The structure was identified by reference substance to be p-coumaril acid. CONCLUSION: The methyl glucoside metabolite in rat from the main component parts of trans-6-O-p-coumaroyl scandoside methyl ester droppings of vines in Diffusa effective extracts is p-coumaril acid. This experiment provides a theortical basis for studying chemical compositions and pharmacodynamic action of Diffusa.

[Simultaneous determination of sulfonamides and fluoroquinolones residues in chicken by high performance liquid chromatography-electrospray tandem mass spectrometry].

A method was developed for the simultaneous determination of 10 residual antibiotics--three sulfonamides (sulfadiazine, sulfamethazine and sulfamethoxydiazine) and seven fluoroquinolones (enoxacin, norfloxacin, enrofloxacin, fleroxacin, levofloxacin, lomefloxacin and ciprofloxacin) in chicken by high performance liquid chromatography-electrospray tandem mass spectrometry (HPLC-ESI-MS2). The sample was extracted with 2% acetic acid-acetonitrile for three times and defatted with n-hexane, then purified by an ENVI-18 solid-phase extraction column. After evaporation, the residue was dissolved in the mobile phase of 1 mL. The HPLC separation was performed with a gradient elution program of acetonitrile and water (containing 0.05% formic acid) as the mobile phase. The identification and quantification were done with mass spectrometry. MS2 fragmentation pathways of the ten antibiotics were also analyzed. Good linearities were observed in the range from 0.02 to 2.0 mg/L with correlation coefficients above 0.998 8. The limits of detection (LOD) were 1.10 -6.85 microg/kg and the limits of quantification (LOQ) were 3.68 -22.85 microg/kg. The average recoveries of 10 antibiotics ranged from 68.9% to 102.6% with relative standard deviations below 8.6% (n = 3). The experimental results show that this method is of high sensitivity, good reproducibility, better determination capacity and shorter analysis time. The method can be used for the multi-residue analysis of sulfonamides and fluoroquinolones in animal foods.