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1.
J Colloid Interface Sci ; 581(Pt A): 177-184, 2021 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-32771729

RESUMO

Shaping metal-organic frameworks (MOFs) powders into formed bodies plays a crucial role in opening up the excellent properties of MOFs to a broad range of applications. Gallate-based MOFs, termed as M-gallate (M = Co, Mg, Ni), have shown excellent performance for adsorption separation of C2 hydrocarbons. However, the industrial applications of MOF powders will inevitably confront problems of high pressure drop, pipe blockage, and dust pollution. Herein, we use hydroxypropyl cellulose (HPC) as a binder to produce gallate-based MOFs pellets. The crystal structure of the well-shaped materials after molding remained intact, and the surface area of the materials hardly decreases after shaping. Adsorption isotherms of C2 hydrocarbons including ethylene, ethane and acetylene on the activated powders and pellets of M-gallate were recorded and compared with the outperformers. The shaped pellets were also examined by breakthrough experiments on the fixed-bed separation of C2H2/C2H4 (1:99, v/v) and C2H4/C2H6 (50:50, v/v) gas mixtures. These results proved that M-gallate pellets was promising candidates for the practical industrial realization of C2 hydrocarbons separation.

2.
Opt Express ; 28(12): 17708-17722, 2020 Jun 08.
Artigo em Inglês | MEDLINE | ID: mdl-32679975

RESUMO

We develop a stress-released stoichiometric silicon nitride (Si3N4) fabrication process for dispersion-engineered integrated silicon photonics. To relax the high tensile stress of a thick Si3N4 film grown by low-pressure chemical vapor deposition (LPCVD) process, we grow the film in two steps and introduce a conventional dense stress-release pattern onto a ∼400nm-thick Si3N4 film in between the two steps. Our pattern helps minimize crack formation by releasing the stress of the film along high-symmetry periodic modulation directions and helps stop cracks from propagating. We demonstrate a nearly crack-free ∼830nm-thick Si3N4 film on a 4" silicon wafer. Our Si3N4 photonic platform enables dispersion-engineered, waveguide-coupled microring and microdisk resonators, with cavity sizes of up to a millimeter. Specifically, our 115µm-radius microring exhibits an intrinsic quality (Q)-factor of ∼2.0×106 for the TM00 mode and our 575µm-radius microdisk demonstrates an intrinsic Q of ∼4.0×106 for TM modes in 1550nm wavelengths.

3.
Pharmacol Res ; 155: 104684, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-32045667

RESUMO

Human antigen R (HuR), also known as HuA and embryonic lethal abnormal vision-like 1 (ELAVL1), is a ubiquitously expressed RNA binding protein and functions as an RNA regulator and mediates the expression of various proteins by diverse post-transcriptional mechanisms. HuR has been well characterized in the inflammatory responses and in the development of various cancers. The importance of HuR-mediated roles in cell signaling, inflammation, fibrogenesis and cancer development in the liver has attracted a great deal of attention. However, there is still a substantial gap between the current understanding of the potential roles of HuR in the progression of liver disease and whether HuR can be targeted for the treatment of liver diseases. In this review, we introduce the function and mechanistic characterization of HuR, and then focus on the physiopathological roles of HuR in the development of different liver diseases, including hepatic inflammation, alcoholic liver diseases, non-alcoholic fatty liver diseases, viral hepatitis, liver fibrosis and liver cancers. We also summarize existing approaches targeting HuR function. In conclusion, although characterizing the liver-specific HuR function and demonstrating the multi-level regulative networks of HuR in the liver are still required, emerging evidence supports the notion that HuR represents a potential therapeutic target for the treatment of chronic liver diseases.

4.
Nat Commun ; 10(1): 5483, 2019 12 02.
Artigo em Inglês | MEDLINE | ID: mdl-31792223

RESUMO

The development of facile and efficient polymerizations toward functional polymers with unique structures and attractive properties is of great academic and industrial significance. Here we develop a straightforward C-H-activated polyspiroannulation route to in situ generate photoresponsive spiro-polymers with complex structures. The palladium(II)-catalyzed stepwise polyspiroannulations of free naphthols and internal diynes proceed efficiently in dimethylsulfoxide at 120 °C without the constraint of apparent stoichiometric balance in monomers. A series of functional polymers with multisubstituted spiro-segments and absolute molecular weights of up to 39,000 are produced in high yields (up to 99%). The obtained spiro-polymers can be readily fabricated into different well-resolved fluorescent photopatterns with both turn-off and turn-on modes based on their photoinduced fluorescence change. Taking advantage of their photoresponsive refractive index, we successfully apply the polymer thin films in integrated silicon photonics techniques and achieve the permanent modification of resonance wavelengths of microring resonators by UV irradiation.

5.
J Environ Manage ; 224: 376-386, 2018 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-30059935

RESUMO

Sludge collected from industrial wastewater treatment possesses a threatening effect on environment, and changing it into functional material provides an alternative for its disposal. Biochar synthesized by pyrolysis of sludge obtained from coking wastewater treatment was evaluated for the catalytic ozonation of phenol in aqueous solution. The present work focused on testing the catalytic performance of biochar, deducing the kinetics of phenol removal in various reaction conditions, and finally elucidating the mechanism of biochar-enhanced phenol removal. The results demonstrated that biochars produced at pyrolysis temperatures of 700 and 900 °C revealed highly comparable catalytic activity in phenol ozonation, leading to around 95% phenol removal within 30 min reaction, due to the abundant carbonyl groups on biochar surface. The biochar, however, was suffered from poor stability, which was attributed to biochar loss and changes in surface chemistry. On the basis of examining reaction variables, an empirical kinetic model was developed well matching experimental results. It was found that ozone concentration adsorbed on biochar surface was first increased with a peak (3.8 mg/L for biochar obtained at 700 °C) at reaction time 10 min, after which it decreased along with proceeding reaction. In light of radical scavenging test, superoxide radical (O2-) was identified as main radical species produced from the interaction of ozone with biochar surface, while hydroxyl radical (OH) played negligible role in biochar catalytic ozonation. The promoting mechanism of bicarbonate on phenol ozonation was verified to be the generation of O2- via series reactions of HCO3- with OH and ozone, apart from increase in solution pH. These results provide important implications for future recycling of coking wastewater treatment sludge in environmental remediation.


Assuntos
Carvão Vegetal , Fenol/isolamento & purificação , Poluentes Químicos da Água/isolamento & purificação , Coque , Ozônio , Fenol/química , Fenóis , Esgotos , Águas Residuárias , Poluentes Químicos da Água/química
6.
Environ Sci Pollut Res Int ; 25(3): 2389-2400, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-29124641

RESUMO

Coking wastewater after biological treatment still possesses potential environmental risk and should be mineralized further. This work focused on the mineralization of bio-treated coking wastewater using catalytic ozonation by NiO. First, oxalic acid, the typical by-product of advanced oxidation process (AOPs), was used to test the catalytic performance of NiOs, prepared by modified hydrothermal methods upon addition of different surfactants. This demonstrated that NiO upon addition of hexadecyltrimethylammonium (CTAB) had the best catalytic activity, due to its high concentration surface hydroxyl density and strong stability. Moreover, the best NiO was applied for the catalytic ozonation of bio-treated coking wastewater. Under our experimental conditions, the total organic carbon (TOC) removal reached 100% after 420 min. In addition, the spectroscopic analysis suggested that compounds with conjugated structures could be significantly removed by both ozonation and catalytic ozonation. Some of these substances were transformed into by-products with aliphatic C-C and O=C-O groups such as organic acids that can inhibit further mineralization.


Assuntos
Coque , Níquel/química , Ácido Oxálico/química , Ozônio/química , Águas Residuárias/química , Purificação da Água/métodos , Catálise , Oxirredução , Poluentes Químicos da Água/análise
7.
Environ Sci Pollut Res Int ; 25(3): 2401, 2018 01.
Artigo em Inglês | MEDLINE | ID: mdl-29288295

RESUMO

In Table 1, "SO2-4" and "NO-3" should be corrected to "[Formula: see text]" and "[Formula: see text]", respectively. The original article was corrected.

8.
Opt Express ; 23(4): 5014-26, 2015 Feb 23.
Artigo em Inglês | MEDLINE | ID: mdl-25836536

RESUMO

We study the propagation of orbital angular momentum (OAM) modes in rectangular multimode waveguides. Due to the multimode interference effect, an OAM mode input forms self-images at certain propagation distances. As OAM modes can be decomposed as the superposition of a pair of quarter-wave phase-shifted even and odd modes, their symmetry properties lead to two different self-imaging categories - forming the OAM-maintaining and the field-splitting self-images. We analyze these phenomena using multimode interference theory, and establish the rules governing the OAM-maintaining self-imaging, which allows the multi-mode interference waveguides to be used as OAM mode splitters and couplers.

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