Reconstruction of surface structure of MoBiTeO/SiO2 catalyst during propane selective oxidation

The catalytic performance of MoBiTeO/SiO2 for selective oxidation of propane to acrolein was investigated, and the catalyst was characterized by means of X-ray powder diffraction, in-situ laser Raman spectroscopy, in-situ laser Raman spectroscopy, and X-ray photoelectron spectroscopy. The results showed that Te-polymolybdate species were the main active phase on the fresh catalyst. Under the conditions of 570 degrees C and C3H8/O-2/N-2 = 1.2/1/4, some Te species in the catalyst were reduced to metal Te which was volatilized during the reaction, and therefore the active surface phase of the catalyst was reconstructed, leading to the formation of MoO3 species. Along with the active surface reconstruction, both the conversion of propane and the selectivity for acrolein were increased, which was attributed to the synergistic effect between Te-polymolybdate and MoO3

Efficient Catalytic Degradation of Phenol with Phthalocyanine-Immobilized Reduced Graphene–Bacterial Cellulose Nanocomposite

In this report, phthalocyanine (Pc)/reduced graphene (rG)/bacterial cellulose (BC) ternary nanocomposite, Pc-rGBC, was developed through the immobilization of Pc onto a reduced graphene–bacterial cellulose (rGBC) nanohybrid after the reduction of biosynthesized graphene oxide-bacterial cellulose (GOBC) with N2H4. Field emission scanning electron microscopy (FESEM) and Fourier transform infrared spectroscopy (FT-IR) were employed to monitor all of the functionalization processes. The Pc-rGBC nanocomposite was applied for the treatment of phenol wastewater. Thanks to the synergistic effect of BC and rG, Pc-rGBC had good adsorption capacity to phenol molecules, and the equilibrium adsorption data fitted well with the Freundlich model. When H2O2 was presented as an oxidant, phenol could rapidly be catalytically decomposed by the Pc-rGBC nanocomposite; the phenol degradation ratio was more than 90% within 90 min of catalytic oxidation, and the recycling experiment showed that the Pc-rGBC nanocomposite had excellent recycling performance in the consecutive treatment of phenol wastewater. The HPLC result showed that several organic acids, such as oxalic acid, maleic acid, fumaric acid, glutaric acid, and adipic acid, were formed during the reaction. The chemical oxygen demand (COD) result indicated that the formed organic acids could be further mineralized to CO2 and H2O, and the mineralization ratio was more than 80% when the catalytic reaction time was prolonged to 4 h. This work is of vital importance, in terms of both academic research and industrial practice, to the design of Pc-based functional materials and their application in environmental purification

Design and implementation of an optimized double closed-loop control system for MEMS vibratory gyroscope

peer reviewe

A highly reliable integrated PDMS interconnector with a long cast flange for microfluidic systems

This paper presents a highly reliable macro to micro domain interconnection technology for microfluidic applications using Polydimethylsiloxane (PDMS) casting techniques. Characteristic to the interconnectors are long flanges fabricated in the PDMS film; therefore the contact area between PDMS and tubes is considerably increased compared to other interconnection technologies. Thus, both glass capillaries and Polytetrafluoroethylene (PTFE) tubes can be held in position very reliably and rigidly. To test the reliability of the interconnectors, PTFE tubes were successfully connected to microfluidic chips without the aid of any liquid adhesives. Both leakage and pull-out tests demonstrated the functionality and reliability of the PDMS interconnectors; no leakage was detected under a working pressure up to 400 kPa. A pull-out test yielded a pull-out force of 22.45 N. Furthermore, once a casting mould is fabricated, it can be re-used as a template repeatedly achieving a low cost technology and making it suitable for batch production

Influence of H4SiW12O40 loading on hydrocracking activity of non-sulfide Ni-H4SiW12O40/SiO2 catalysts

The effect of H4SiW12O40 loading on the catalytic performance of the reduced Ni-H4SiW12O40/SiO2 catalysts for hydrocracking of n-decane with or without the presence of thiophene and pyridine is studied. The catalysts were characterized by BET, XRD, Raman, XPS, H-2-TPR, H-2-TPD, NH3-TPD and FT-IR of pyridine adsorption. It was found that addition of H4SiW12O40 to the system increases the catalytic activity and the promoting effect is a function of the H4SiW12O40 loading. The best result was obtained on 5%Ni-50%H4SiW12O40/SiO2 catalyst which shows the highest activity for hydrocracking of n-decane and excellent tolerance to the sulfur and nitrogen compounds in the feedstock. The results showed that a suitable amount of H4SiW12O40 loading on the 5%Ni/SiO2 catalyst increases the amount of both hydrogen adsorbed and Bronsted acid and Lewis acid sites on the catalyst. The high catalytic performance of the catalyst can be related to the nature of H4SiW12O40 and the proper balance between metal and acid functions. (C) 2009 Elsevier Ltd. All rights reserved.Ministry of Science and Technology of China [2004CB217805, 2010CB226903

Direct synthesis and superior catalytic performance of V-containing SBA-15 mesoporous materials for oxidative dehydrogenation of propane

V-containing SBA-15 mesoporous materials have been directly synthesized in an acidic and peroxidic medium. Compared to V/SBA-15 and V/SiO2 samples prepared by impregnation method, the materials thus synthesized show larger surface areas, higher dispersion and reducibility of VOx species, and superior catalytic performance for oxidative dehydrogenation of propane

CASB: a concanavalin A‐based sample barcoding strategy for single‐cell sequencing

Abstract Sample multiplexing facilitates single‐cell sequencing by reducing costs, revealing subtle difference between similar samples, and identifying artifacts such as cell doublets. However, universal and cost‐effective strategies are rather limited. Here, we reported a concanavalin A‐based sample barcoding strategy (CASB), which could be followed by both single‐cell mRNA and ATAC (assay for transposase‐accessible chromatin) sequencing techniques. The method involves minimal sample processing, thereby preserving intact transcriptomic or epigenomic patterns. We demonstrated its high labeling efficiency, high accuracy in assigning cells/nuclei to samples regardless of cell type and genetic background, and high sensitivity in detecting doublets by three applications: 1) CASB followed by scRNA‐seq to track the transcriptomic dynamics of a cancer cell line perturbed by multiple drugs, which revealed compound‐specific heterogeneous response; 2) CASB together with both snATAC‐seq and scRNA‐seq to illustrate the IFN‐γ‐mediated dynamic changes on epigenome and transcriptome profile, which identified the transcription factor underlying heterogeneous IFN‐γ response; and 3) combinatorial indexing by CASB, which demonstrated its high scalability

Lightweight All Graphene‐Based Two‐Phase Heat Transport Devices

Abstract Graphene‐based composites show great potential in the development of lightweight functional devices and systems, and polymers are usually used as binders to enhance the mechanical properties of these composites. Due to the low thermal conductivity of the polymer and the high inherent interfacial thermal resistance between polymer and graphene, however, the developed devices and systems generally possess low thermal conductivity, which seriously limits their further thermal‐related applications. Here, a lightweight two‐phase heat transport device (TPHTD) based on a vapor‐liquid phase transition‐based heat transfer by using a graphene‐based composite material as the casing is generated. The graphene‐based TPHTD has high thermal conductivity of up to 1408 W (mK)−1 and realizes ultra‐high specific thermal conductivity of ≈5600 W (mKg)−1. This graphene‐based device with lightweight and high heat transfer capacity offers new opportunities for efficient thermal management of compact, portable, or wearable electronic and power systems