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1.
Inorg Chem ; 59(6): 3828-3837, 2020 Mar 16.
Artigo em Inglês | MEDLINE | ID: mdl-32129611

RESUMO

By using the reduced Schiff base tricarboxylate ligand H3cip, one novel 3D Cd-based coordination polymer (Cd-CP) with the formula [Cd(Hcip)(bpea)0.5(H2O)]n (H3cip = 5-(3-carboxybenzylamino)isophthalic acid, bpea = 1,2-bis(4-pyridyl)ethane) has been solvothermally synthesized. The prepared Cd-CP possesses a 4-connected CdSO4 net based on dinuclear {Cd2} units. Luminescence measurements revealed that the complex exhibited ratiometric turn-on luminescence responses toward Al3+ and Cr3+ with a significant color change, which could be easily distinguished by the naked eye under ultraviolet light. Cd-CP can also respond to Fe3+ through a turn-off mechanism. Interestingly, the luminescence quenched by Fe3+@Cd-CP can be recovered and increased significantly by adding some competitive Al3+, while Cr3+ can only marginally increase the luminescence intensity of Fe3+@Cd-CP. Moreover, the detection of the three aforementioned metal ions can be realized by using Cd-CP-coated test papers, extending the potential application regions of the reported material to point-of-care tests and environmental field studies.

2.
Sci Total Environ ; 712: 136500, 2020 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-31931205

RESUMO

An efficient approach for synchronous volatile fatty acids (VFAs) promotion, phosphorus fixation and pathogens inactivation during waste activated sludge (WAS) anaerobic fermentation was achieved with optimal calcium hypochlorite (Ca(ClO)2) stimulation. The maximal VFAs were 3.6 folds of control in reactors with 0.01 g Ca(ClO)2/g TSS addition. The low dosage of Ca(ClO)2 enhanced WAS solubilization and hydrolysis by disrupting the extracellular polymeric substance (EPS) effectively. Sufficient substrates for fermentative bacteria were thereby provided with the maintenance of acceptable microbial activity and viability. However, high dosage of Ca(ClO)2 deteriorated the performance of anaerobic fermentation due to its strong oxidative ability, resulting in cell lysis greatly. Moreover, the largely released phosphorus during WAS fermentation was effectively precipitated and removed by the combination of Ca2+ at 0.01 g Ca(ClO)2/g TSS dosage. In addition, Ca(ClO)2 had distinguished effects on pathogens inactivation. The simultaneous phosphorus fixation and pathogens reduction during VFAs production increased the utilization value of fermentation liquid and benefitted the further disposal of fermented sludge.

3.
ACS Appl Mater Interfaces ; 12(3): 3764-3772, 2020 Jan 22.
Artigo em Inglês | MEDLINE | ID: mdl-31894957

RESUMO

High-quality pure acetylene (C2H2) is a kind of crucial starting material for various value-added products. However, selective capture of C2H2 from the main impurity of CO2 via porous absorbents is a great challenge, as they possess extremely similar kinetic diameters and boiling points, as well as the explosive and reactive properties of C2H2. Herein, we report a porous coordination polymer (PCP), (NTU-55), which assembled from the coordination between a Cu dimer and a newly designed ligand with a nonmetal selenium (Se) site. Static single-component adsorption and dynamic breakthrough experiments reveal that desolvated NTU-55 can completely adsorb C2H2 from the C2H2/CO2 mixture (1/4, v/v) at 298 K, along with higher C2H2 capacity and much lower binding energy. The origin of this separation, as comprehensively revealed by density functional theory (DFT) calculations, is derived from the interaction discriminatory of C2H2 and CO2 toward accessible Se and Cu adsorption sites. To the best of our knowledge, this is the first time to find the positive effect of nonmetal Se sites for selective C2H2 capture.

4.
J Hazard Mater ; 384: 121311, 2020 02 15.
Artigo em Inglês | MEDLINE | ID: mdl-31585278

RESUMO

Metabolic uncouplers are widely used for reducing excess sludge in biological wastewater treatment systems. However, the formation of microbial products, such as extracellular polymeric substances, polyhydroxyalkanoate and soluble microbial products by activated sludge in the presence of metabolic uncouplers remains unrevealed. In this study, the impacts of a metabolic uncoupler o-chlorophenol (oCP) on the reduction of activated sludge yield and formation of microbial products in laboratory-scale sequencing batch reactors (SBRs) were evaluated for a long-term operation. The results show the average reduction of sludge yield in the four reactors was 17.40%, 25.80%, 33.02% and 39.50%, respectively, when dosing 5, 10, 15, and 20 mg/L oCP. The oCP addition slightly reduced the pollutant removal efficiency and decreased the formation of soluble microbial products in the SBRs, but stimulated the productions of extracellular polymeric substances and polyhydroxyalkanoate in activated sludge. Furthermore, the significant reduction of electronic transport system activity occurred after the oCP addition. Microbial community analysis of the activated sludge indicates dosing oCP resulted in a decrease of sludge richness and diversity in the SBRs. Hopefully, this study would provide useful information for reducing sludge yield in biological wastewater treatment systems and behaviors of activated sludge in the presence of uncouplers.

5.
Artif Cells Nanomed Biotechnol ; 48(1): 68-76, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31852285

RESUMO

Mulberry silkworm cocoon (MSC) carbonisata has been used for the treatment of inflammatory diseases for hundreds of years; however, after years of research efforts, little information is available on its anti-inflammatory components and underlying mechanism. We developed novel carbon dots (CDs) derived from MSC carbonisata (MSC-CDs), for the first time, with an average diameter of 2.26-9.35 nm and a quantum yield (QY) of 6.32%. The MSC-CDs were prepared using a modified pyrolysis method, and no further modification and external surface passivation agent was required. With abundant surface groups, MSC-CDs showed distinct solubility and bioactivity. In this study, we innovatively used three classical experimental models of inflammation to evaluate the anti-inflammatory bioactivity of MSC-CDs. The results indicated that MSC-CDs exhibited marked anti-inflammatory bioactivity which was likely mediated by inhibition of the expression of interleukin-6 and tumour necrosis factor-α. These results suggest that MSC-CDs possess a remarkable anti-inflammatory property, which provides evidence to support further investigation of the considerable potential and effective material basis of this traditional Chinese medicine.

6.
Acta Crystallogr C Struct Chem ; 75(Pt 12): 1666-1674, 2019 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-31802757

RESUMO

A novel three-dimensional coordination polymer, namely, poly[[diaquabis(µ-4,4'-bipyridine)bis{µ3-5-[(2-carboxyphenoxy)methyl]isophthalato}tricadmium(III)] dimethylformamide monosolvate 2.5-hydrate], {[Cd3(C16H9O7)2(C10H8N2)2(H2O)2]·2C3H7NO·5H2O}n, was obtained by the reaction of ether-linked 5-[(2-carboxyphenoxy)methyl]isophthalic acid (H3L) with CdII salts in the presence of 4,4'-bipyridine (bpy) under solvothermal conditions. In this complex, the CdII centres are connected by the carboxylate ligands to form two-dimensional wave-like layers, which are pillared by bpy ligands and extended into a rare three-dimensional (3,6)-connected sqc27 framework. The complex demonstrated good water stability and strong luminescence emissions. It not only possesses excellent luminescence sensing activities toward Fe3+ and Cr2O72- in aqueous solution, but can also distinguish between Cr2O72- and CrO42- by luminescence. Furthermore, it could be simply and quickly regenerated at least five times. A study of the sensing mechanism indicated that luminescence quenching may be related to the energy competition between the complex and sensing analytes.

7.
Inorg Chem ; 58(23): 16241-16249, 2019 Dec 02.
Artigo em Inglês | MEDLINE | ID: mdl-31710224

RESUMO

In the design and construction of porous materials, these with exceptional structure and composition are often highly expected, as they may offer unique nanopore space for desired applications. Here, a new family of quasi-3D and a 3D porous coordination polymers (PCPs) (termed NTU-43 to NTU-50) were constructed via an evolution strategy from a layered structure (termed NTU-42). Single gas adsorption isotherms of CO2, N2, and CH4 display the dependency of gas capacity on optimized effects of pore size, functionality, and charged framework of these quasi-3D PCPs, where NTU-45 and NTU-46, the two with NH2-BDC and OH-BDC bidentate linkers (NH2-BDC = 2-aminoterephthalic acid and OH-BDC = 2-hydroxyterephthalic acid) have demonstrated outstanding ability for selective CO2 uptake. To the best of our knowledge, this is the first time to well explore the synergistic effects toward gas adsorption on a platform of quasi-3D frameworks. More importantly, the efficient CO2 capture from CO2/CH4 and CO2/N2 mixtures has been also validated by breakthrough experiments under continuous and dynamic conditions at 298 K.

8.
Nanomaterials (Basel) ; 9(11)2019 Nov 05.
Artigo em Inglês | MEDLINE | ID: mdl-31694221

RESUMO

The efficient transformation of carbon dioxide into useful chemical feedstock is of great significance, attracting intense research interest. The widely studied porous-coordinated polymers possess large pores to adsorb guest molecules and further allow the contact and to transfer the substrate molecule within their microenvironment. Here we present the synthesis of a silver-based metal-organic frameworks (MOFs) material with a three-dimensional structure by incorporating a tetraphenyl-ethylene moiety as the four-point connected node via the solvothermal method. This polymer exhibits as an efficient heterogeneous catalyst for the carboxylative cyclization of CO2 to α-methylene cyclic carbonates in excellent yields. Moreover, the introduction of silver (Ag (I)) chains in this framework shows the specific alkynophilicity to activate C≡C bonds in propargylic alcohols to greatly accelerate the efficient conversion, and the large pores in the catalyst exhibit a size-selective catalytic performance.

9.
Molecules ; 24(22)2019 Nov 16.
Artigo em Inglês | MEDLINE | ID: mdl-31744056

RESUMO

Gout is a disease with a high incidence and causing great harm, and the current treatment drugs are not satisfactory. In this study, novel water-soluble carbon dots (CDs) with anti-gout effect, named Puerariae lobatae Radix CDs (PLR-CDs), are reported. PLR-CDs were synthesized with an improved pyrolysis method at 300 °C, and their characterization was performed with multifaceted approaches, such as transmission electron microscopy (TEM) and ultraviolet-visible (UV-vis) and Fourier-transform infrared (FTIR) spectroscopy. In addition, the biocompatibility of PLR-CDs was studied using the cell counting kit (CCK)-8 in LO2 cells and RAW264.7 cells, and the anti-gout activity of PLR-CDs was examined on animal models of hyperuricemia and gouty arthritis. The characterization of PLR-CDs indicated that they were nearly spherical, with diameters ranging from 3.0 to 10.0 nm, and the lattice spacing was 0.283 nm. The toxicity experiment revealed that PLR-CDs were non-poisonous for LO2 cells and RAW264.7 cells at concentrations below 250 µg/mL. The results of pharmacodynamic experiments showed that PLR-CDs could lower the blood uric acid level in model rats by inhibiting the activity of xanthine oxidase and reduce the degree of swelling and pathological damage of gouty arthritis. Thus, PLR-CDs with anti-gout biological activity and good biocompatibility have the prospect of clinical application for the treatment of gout.

10.
Bioresour Technol ; 292: 121978, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31415988

RESUMO

This study aimed to explore the production of polyhydroxyalkanoates (PHA) and selection of PHA-accumulating microorganisms in bioreactors fed with rice winery wastewater at various organic loading rates (OLRs). The substrate utilization, sludge properties, PHA synthesis and microbial community structure of three sequencing batch reactors were monitored. The results show the highest PHA yield (0.23 g/g) was achieved in one of the three reactors with an OLR of 2.4 g COD/L/d, in which Zoogloea was the most dominant PHA-accumulating microorganism. To quantify the PHA production and track the population changing profiles of the PHA-accumulating microorganisms in the long-term reactor operation, the Activated Sludge Model No. 3 was modified with two different heterotrophic microorganisms responding differently with the same substrate. The modeling results indicate that a moderate OLR (>2.4 gCOD/L/d) was beneficial for PHA production. The results are useful for understanding the PHA production from industrial wastewaters and selection of PHA-accumulating microorganisms.


Assuntos
Oryza , Poli-Hidroxialcanoatos , Reatores Biológicos , Esgotos , Águas Residuárias
11.
Nanomedicine (Lond) ; 14(22): 2925-2939, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-31418646

RESUMO

Aim: To explore the antihyperuricemia and anti-gouty arthritis activities of Aurantii fructus immaturus carbonisata-derived carbon dots (AFIC-CDs). Materials & methods: The AFIC-CDs were characterized using transmission electron microscopy; high-resolution transmission electron microscopy; ultraviolet, fluorescence, Fourier-transform infrared and x-ray photoelectron spectroscopy; high-performance liquid chromatography; and x-ray diffraction. Antihyperuricemia and anti-gouty arthritis activities of AFIC-CDs were explored in vivo and in vitro. Results: The AFIC-CDs diameter ranged from 1.1 to 4.4 nm, with a yield of 7.2%. AFIC-CDs reduced serum uric acid by inhibiting xanthine oxidase activity in hyperuricemia rats and inhibited xanthine oxidase activity in vitro. AFIC-CDs improved gouty arthritis induced by monosodium urate crystals in vivo and in vitro. Conclusion: AFIC-CDs may be a potential treatment for gout.

12.
Biofabrication ; 12(1): 015004, 2019 10 21.
Artigo em Inglês | MEDLINE | ID: mdl-31470437

RESUMO

The ability to fabricate perfusable, small-diameter vasculature is a foundational step toward generating human tissues/organs for clinical applications. Currently, it is highly challenging to generate vasculature integrated with smooth muscle and endothelium that replicates the complexity and functionality of natural vessels. Here, a novel method for directly printing self-standing, small-diameter vasculature with smooth muscle and endothelium is presented through combining tailored mussel-inspired bioink and unique 'fugitive-migration' tactics, and its effectiveness and advantages over other methods (i.e. traditional alginate/calcium hydrogel, post-perfusion of endothelial cells) are demonstrated. The biologically inspired, catechol-functionalized, gelatin methacrylate (GelMA/C) undergoes rapid oxidative crosslinking in situ to form an elastic hydrogel, which can be engineered with controllable mechanical strength, high cell/tissue adhesion, and excellent bio-functionalization. The results demonstrate the bioprinted vascular construct possessed numerous favorable, biomimetic characteristics such as proper biomechanics, higher tissue affinity, vascularized tissue manufacturing ability, beneficial perfusability and permeability, excellent vasculoactivity, and in vivo autonomous connection (∼2 weeks) as well as vascular remodeling (∼6 weeks). The advanced achievements in creating biomimetic, functional vasculature illustrate significant potential toward generating a complicated vascularized tissue/organ for clinical transplantation.

13.
Dalton Trans ; 48(36): 13541-13545, 2019 Sep 17.
Artigo em Inglês | MEDLINE | ID: mdl-31469147

RESUMO

Simultaneously involving abundant [NH2(CH3)2]+ cations and uncoordinated carboxylate oxygen atoms as dual active sites, two microporous CoII-MOFs (LCU-105 and LCU-106, LCU = Liaocheng University) both exhibit highly selective adsorption of CO2/CH4 and CO2/N2. GCMC theoretical simulations provide good verification of the experimental results.

14.
Inorg Chem ; 58(14): 9469-9475, 2019 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-31265264

RESUMO

Herein, a series of Fe-based catalysts have been designed and prepared by grinding a mixture of MIL-88d and melamine, and then the mixture was followed by pyrolysis. An unusual Fe/Fe3C-activated site is uniformly encapsulated in the N-doped carbon tubes obtained by pyrolysis of the film-like nanocrystals of MIL-88d. Experimental characterizations and theoretical calculations demonstrate that the surface N sites can effectively trap the nitrobenzene and aniline by their phenyl groups with the formation of three C-N bonds that made the catalyst exhibit excellent catalytic activity (turnover frequencies of ≤11268 h-1 calculated on the basis of nitrobenzene) and chemoselectivity for the reduction of nitro derivatives under facile conditions.

15.
Acta Crystallogr C Struct Chem ; 75(Pt 6): 657-666, 2019 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-31166917

RESUMO

Reaction of the flexible phenolic carboxylate ligand 2-(3,5-dicarboxylbenzyloxy)benzoic acid (H3L) with nickel salts in the presence of 1,2-bis(pyridin-4-yl)ethylene (bpe) leads to the generation of a mixture of the two complexes under solvolthermal conditions, namely poly[[aqua[µ-1,2-bis(pyridin-4-yl)ethylene-κ2N:N']{µ-5-[(2-carboxyphenoxy)methyl]benzene-1,3-dicarboxylato-κ3O1,O1':O3}nickel(II)] dimethylformamide hemisolvate monohydrate], {[Ni(C16H10O7)(C12H10N2)(H2O)]·0.5C3H7NO·H2O}n or {[Ni(HL)(bpe)(H2O)]·0.5DMF·H2O}n, 1, and poly[[diaquatris[µ-1,2-bis(pyridin-4-yl)ethylene-κ2N:N']bis{µ-5-[(2-carboxyphenoxy)methyl]benzene-1,3-dicarboxylato-κ2O1:O5}nickel(II)] dimethylformamide disolvate hexahydrate], {[Ni2(C16H10O7)2(C12H10N2)3(H2O)2]·2C3H7NO·6H2O}n or {[Ni2(HL)2(bpe)3(H2O)2]·2DMF·6H2O}n, 2. In complex 1, the NiII centres are connected by the carboxylate and bpe ligands to form two-dimensional (2D) 4-connected (4,4) layers, which are extended into a 2D+2D→3D (3D is three-dimensional) supramolecular framework. In complex 2, bpe ligands connect to NiII centres to form 2D layers with Ni6(bpe)6 metallmacrocycles. Interestingly, 2D+2D→3D inclined polycatenation was observed between these layers. The final 5-connected 3D self-penetrating structure was generated through further connection of Ni-carboxylate chains with these inclined motifs. Both complexes were fully characterized by single-crystal analysis, powder X-ray diffraction analysis, FT-IR spectra, elemental analyses, thermal analysis and UV-Vis spectra. Notably, an interesting metal/ligand-induced crystal-to-crystal transformation was observed between the two complexes.

16.
Inorg Chem ; 58(9): 6137-6142, 2019 May 06.
Artigo em Inglês | MEDLINE | ID: mdl-31012579

RESUMO

In the field of catalysis, material scientists pay much attention to tuning the activity and chemoselectivity of metal nanoparticles. Herein, we design and successfully synthesize a series of Co NPs which show high performance on hydrogenation of nitroarenes with both activity and chemoselectivity. Co0.15@C/PC preferentially activates the -C═O bond over -NO2 in water with ammonia borane (AB); however, when the hydrogen source is changes to hydrazine hydrate (HH), the results are the opposite. The Co-based catalyst exhibits exceptionally high catalytic activity (with a TOF value of 10512 h-1, which is approximately 100 times than the akin catalysts) and chemo-selectivity for the hydrogenation of nitro compounds under mild conditions. Additionally, the catalyst can be separated easily by a magnet and shows prominent stabilit, which means that it can be reused for at least 10 cycles.

17.
Environ Pollut ; 247: 1020-1027, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30823330

RESUMO

Metabolic uncouplers are widely used for the in-situ reduction of excess sludge from activated sludge systems. However, the interaction mechanism between the metabolic uncouplers and extracellular polymeric substances (EPS) of activated sludge is unknown yet. In this study, the interactions between a typical metabolic uncoupler, o-chlorophenol (oCP), and the EPS extracted from activated sludge were explored using a suite of spectral methods. The binding constants calculated for the four peaks of three-dimensional excitation-emission matrix fluorescence were in a range of 1.24-1.76 × 103 L/mol, implying that the tyrosine protein-like substances governed the oCP-EPS interactions. Furthermore, the results of Fourier transform infrared spectroscopy, X-ray photoelectron spectroscopy and 1H nuclear magnetic resonance indicated that the carboxyl, carbonyl, amine, and hydroxyl groups of EPS were the main functional groups involved in the formation of the oCP-EPS complex. The results of this study are useful for understanding the interactions between metabolic uncouplers and the EPS of activated sludge as well as their fates in biological wastewater treatment systems.


Assuntos
Clorofenóis/química , Matriz Extracelular de Substâncias Poliméricas/química , Esgotos/química , Águas Residuárias/química , Purificação da Água/métodos , China
18.
Inorg Chem ; 58(7): 4067-4070, 2019 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-30895784

RESUMO

A flexible-ligand-based metal-organic cage containing functional amide and secondary amino groups as guest-interacted sites has been synthesized. The synergistic effect between the size-defined cavity and self-adaptive backbone endows the cage excellent properties for the selective recognition of specific natural guests over other similar molecules via fluorescent response.

19.
ACS Appl Mater Interfaces ; 11(8): 7914-7926, 2019 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-30720269

RESUMO

Two series of lanthanide metal-organic frameworks (Ln-MOFs) from two structurally related flexible carboxylate-based ligands were solvothermally synthesized. H3L2 with additional -CH2- group provides more flexibility and different coordination modes and conformations compared with H3L1. As a result, 2-Ln MOFs are modulated from two-dimensional kgd of 1-Ln to three-dimensional rtl topological frameworks and further achieve enhanced chemical stability. The Eu- and Tb-MOFs exhibit strong fluorescent emission at the solid state because of the antenna effect of the ligands. Interestingly, the emissions can be tuned by simply doping Eu3+ and Tb3+ of different concentrations within the Eu xTb1- x MOFs. Notably, 2-Ln MOFs realize nearly white light emission by means of a trichromatic approach (red of Eu(III), green of Tb(III), and blue of the H3L2 ligand). Furthermore, 2-Ln MOFs also exhibit water stability and demonstrate high selective and sensitive sensing activities toward Fe(III) and Cr(VI) in aqueous solutions. The results further highlight the importance of the ligand flexibility on tuning MOF structures with improved structural stability and ion-sensing properties.

20.
J Hematol Oncol ; 12(1): 18, 2019 02 18.
Artigo em Inglês | MEDLINE | ID: mdl-30777106

RESUMO

BACKGROUND: Gastric cancer (GC) is a common cancer in Asia and currently lacks a targeted therapy approach. Mesothelin (MSLN) has been reported to be expressed in GC tissue and could be targeted by chimeric antigen receptor (CAR) T cells. Mesothelin targeting CAR-T has been reported in mesothelioma, lung cancer, breast cancer, and pancreas cancer. However, the feasibility of using anti-MSLN CAR T cells to treat GC remains to be studied. METHODS: We verified MSLN expression in primary human GC tissues and GC cell lines and then redirected T cells with a CAR containing the MSLN scFv (single-chain variable fragment), CD3ζ, CD28, and DAP10 intracellular signaling domain (M28z10) to target MSLN. We evaluated the function of these CAR T cells in vitro in terms of cytotoxicity, cytokine secretion, and surface phenotype changes when they encountered MSLN+ GC cells. We also established four different xenograft GC mouse models to assess in vivo antitumor activity. RESULTS: M28z10 T cells exhibited strong cytotoxicity and cytokine-secreting ability against GC cells in vitro. In addition, cell surface phenotyping suggested significant activation of M28z10 T cells upon target cell stimulation. M28z10 T cells induced GC regression in different xenograft mouse models and prolonged the survival of these mice compared with GFP-transduced T cells in the intraperitoneal and pulmonary metastatic GC models. Importantly, peritumoral delivery strategy can lead to improved CAR-T cells infiltration into tumor tissue and significantly suppress the growth of GC in a subcutaneous GC model. CONCLUSION: These results demonstrate that M28z10 T cells possess strong antitumor activity and represent a promising therapeutic approach to GC.

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