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1.
Sci Total Environ ; 877: 162718, 2023 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-36914128

RESUMO

To comprehensively clarify the pollution characteristics of persistent toxic substances, the Soil and Air Monitoring Program Phase III (SAMP-III) was conducted in 2019 in China. In total, 154 surface soil samples were collected across China, and 30 unsubstituted polycyclic aromatic hydrocarbons (U-PAHs) and 49 methylated PAHs (Me-PAHs) were analyzed in this study. The mean concentrations of total U-PAHs and Me-PAHs were 540 ± 778 and 82.0 ± 132 ng/g dw, respectively. Northeastern China and Eastern China are the two regions of concern with high PAH and BaP equivalency levels. Compared with SAMP-I (2005) and SAMP-II (2012), an obvious upward temporal trend followed by a downward trend of PAH levels was observed in the past 14 years for the first time. The mean concentrations of 16 U-PAHs were 377 ± 716, 780 ± 1010, and 419 ± 611 ng/g dw in surface soil across China for the three phases, respectively. Considering rapid economic growth and energy consumption, an increasing trend from 2005 to 2012 was expected. From 2012 to 2019, the PAH levels in soils across China decreased by 50 %, which was consistent with the decline in PAH emissions. The period of reduction of PAHs in surface soil coincided with the implementation of Air and Soil Pollution Control Actions in China after 2013 and 2016, respectively. Along with the pollution control actions in China, the pollution control of PAHs and the increase in soil quality can be expected in the near future.

2.
Environ Sci Pollut Res Int ; 29(23): 35253-35268, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35060050

RESUMO

Long-term retention and accumulation of heavy metals in surface water and sediment pose a great threat to the sustainable development of aquatic ecosystems and human health. In this research, macrozoobenthos, and surface water and sediment heavy metal (Mn, Cr, Cu, Ni, Pb, Zn, Cd, and As) samples were collected from 23 sites in the upper and middle reaches of the Heihe River in the summers of 2019-2020. The interrelationships between heavy metals and macrozoobenthos were analyzed by Pearson correlation analysis and redundancy analysis (RDA), and the contamination level and potential ecological risk of the heavy metals in surface water and sediments were assessed by comprehensive pollution index (WQI), single potential ecological risk index ([Formula: see text]), and sediment quality guideline-quotient (SQG-Q), respectively. The results showed that the level of heavy metal pollution in the surface water of the Heihe River was extremely low, but the contents of Mn and Pb exceeded the third class of surface water environmental quality standards (GB 3838-2002). The spatial distribution of heavy metals in surface sediments were significantly different, and the average concentration of 8 heavy metals exceeded the background values of Gansu Province. Meanwhile, the pollution level of heavy metals in surface sediments was high pollution, and the ecological risk level was moderate risk. Combining [Formula: see text] and SQG-Q evaluations showed that Cd, Ni, and Cr were the main ecological risk factors. In addition, the distribution coefficients of Cr and Cd were low, indicating that Cr and Cd were easily released from the surface sediments, causing secondary pollution. In terms of the source of the heavy metals, Cu, As, Zn, Cr, and Ni mainly came from industrial and agricultural wastewaters, Pb was from the mining industry and natural sources, and Mn and Cd mainly came from tailings and their landfill leachate. Basommatophora and Araneae can be used as potential indicator organisms for heavy metal pollution in surface water, and Basommatophora, Coleoptera, Hemiptera, and Araneae can be used as indicator species for heavy metal pollution in surface sediments. The study showed that macroinvertebrate community characteristics had a sensitive response to heavy metals in the surface waters and sediments of the Heihe River, which can be used to evaluate the pollution status of heavy metals in inland rivers.


Assuntos
Metais Pesados , Poluentes Químicos da Água , Cádmio/análise , China , Ecossistema , Monitoramento Ambiental/métodos , Sedimentos Geológicos/análise , Humanos , Chumbo/análise , Metais Pesados/análise , Medição de Risco/métodos , Água/análise , Poluentes Químicos da Água/análise , Qualidade da Água
3.
Environ Sci Pollut Res Int ; 29(2): 2911-2923, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34379262

RESUMO

Spatial variations in grain size parameters can reflect river sediment transport patterns and depositional dynamics. Therefore, 22 surficial sediment samples taken from the Heihe River and its cascade reservoirs were analyzed to better understand the impact of cascade reservoir construction on sediment transport patterns in inland rivers in China. The results showed that the longitudinal distribution of sediment grain size in the Heihe River was significantly affected by the influence of the cascade reservoirs. The retention rate in the cascade reservoir of the Heihe River reached 79% (193.53 Mt/year), which caused most of the fine sand to accumulate in the reservoir, and the sediment fining degree reached approximately 50%. However, the water discharged from the dam caused serious erosion of the riverbed and coarsening of the sediment, and the coarsening degree was approximately 500%. The backwater zone of the reservoir was influenced by both backwater and released water, and the coarsening degree of sediment was approximately 101%. Sedimentary environmental analysis revealed that the characteristics of the sediment grain size in an upstream tributary of the Heihe River were more influenced by source material than by hydrodynamic conditions, while the grain size characteristics of the mainstream sediments were controlled mainly by hydrodynamic conditions. The characteristics of sediment transport in different reaches of the Heihe River were studied, and the results may provide references for the operation of cascade reservoirs and the sediment control of reservoirs.


Assuntos
Rios , Poluentes Químicos da Água , China , Monitoramento Ambiental , Sedimentos Geológicos , Hidrodinâmica , Poluentes Químicos da Água/análise
4.
Mil Med Res ; 8(1): 30, 2021 05 13.
Artigo em Inglês | MEDLINE | ID: mdl-33985568

RESUMO

BACKGROUND: Aeromedical evacuation of patients with burn trauma is an important transport method in times of peace and war, during which patients are exposed to prolonged periods of hypobaric hypoxia; however, the effects of such exposure on burn injuries, particularly on burn-induced lung injuries, are largely unexplored. This study aimed to determine the effects of hypobaric hypoxia on burn-induced lung injuries and to investigate the underlying mechanism using a rat burn model. METHODS: A total of 40 male Wistar rats were randomly divided into four groups (10 in each group): sham burn (SB) group, burn in normoxia condition (BN) group, burn in hypoxia condition (BH) group, and burn in hypoxia condition with treatment intervention (BHD) group. Rats with 30% total body surface area burns were exposed to hypobaric hypoxia (2000 m altitude simulation) or normoxia conditions for 4 h. Deoxyribonuclease I (DNase I) was administered systemically as a treatment intervention. Systemic inflammatory mediator and mitochondrial deoxyribonucleic acid (mtDNA) levels were determined. A histopathological evaluation was performed and the acute lung injury (ALI) score was determined. Malonaldehyde (MDA) content, myeloperoxidase (MPO) activity, and the nucleotide-binding oligomerization domain-like receptor family pyrin domain-containing 3 (NLRP3) inflammasome level were determined in lung tissues. Data among groups were compared using analysis of variance followed by Tukey's test post hoc analysis. RESULTS: Burns resulted in a remarkably higher level of systemic inflammatory cytokines and mtDNA release, which was further heightened by hypobaric hypoxia exposure (P < 0.01). Moreover, hypobaric hypoxia exposure gave rise to increased NLRP3 inflammasome expression, MDA content, and MPO activity in the lung (P < 0.05 or P < 0.01). Burn-induced lung injuries were exacerbated, as shown by the histopathological evaluation and ALI score (P < 0.01). Administration of DNase I markedly reduced mtDNA release and systemic inflammatory cytokine production. Furthermore, the NLRP3 inflammasome level in lung tissues was decreased and burn-induced lung injury was ameliorated (P < 0.01). CONCLUSIONS: Our results suggested that simulated aeromedical evacuation further increased burn-induced mtDNA release and exacerbated burn-induced inflammation and lung injury. DNase I reduced the release of mtDNA, limited mtDNA-induced systemic inflammation, and ameliorated burn-induced ALI. The intervening mtDNA level is thus a potential target to protect from burn-induced lung injury during aeromedical conditions and provides safer air evacuations for severely burned patients.


Assuntos
Altitude , Queimaduras/complicações , DNA Mitocondrial/efeitos dos fármacos , Lesão Pulmonar/tratamento farmacológico , Animais , Queimaduras/tratamento farmacológico , Queimaduras/patologia , Citocinas/análise , Citocinas/sangue , DNA Mitocondrial/análise , DNA Mitocondrial/sangue , Modelos Animais de Doenças , Lesão Pulmonar/etiologia , Lesão Pulmonar/fisiopatologia , Masculino , Ratos , Ratos Wistar
5.
Environ Monit Assess ; 193(2): 53, 2021 Jan 11.
Artigo em Inglês | MEDLINE | ID: mdl-33426620

RESUMO

The Heihe River is a typical inland river under increasing anthropogenic pressure. To explore the characteristics of the macrobenthic assemblages and their relationships with environmental factors in the upstream and midstream regions of this basin, abiotic conditions and macrobenthic assemblages were investigated in the summers of 2018 and 2019. A total of 50 species were collected, and Arthropoda and mollusks were the dominant groups. A significant increase in standing stock was observed from the upstream to midstream, and predators (PR) were the main functional feeding group. A one-way analysis of variance (ANOVA) revealed that the Shannon-Wiener index and Margalef's index values significantly differed at the spatial scale (P < 0.05). A redundancy analysis (RDA) and Pearson correlation analysis showed that the spatial heterogeneity of the macrobenthos was influenced by the biochemical oxygen demand (BOD5), water temperature (WT), total nitrogen (TN), salinity, electrical conductivity (EC), total dissolved solids (TDS), dissolved oxygen (DO), and potassium permanganate index (CODMn) (P < 0.05). The spatial variation of macrobenthos was mainly governed by natural conditions and human disturbances.


Assuntos
Monitoramento Ambiental , Rios , Animais , China , Humanos , Moluscos , Nitrogênio/análise
6.
Acta Crystallogr C Struct Chem ; 76(Pt 1): 23-29, 2020 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-31919304

RESUMO

The Co-MOF poly[[diaqua{µ4-1,1,2,2-tetrakis[4-(1H-1,2,4-triazol-1-yl)phenyl]ethylene-κ4N:N':N'':N'''}cobalt(II)] benzene-1,4-dicarboxylic acid benzene-1,4-dicarboxylate], {[Co(C34H24N12)(H2O)2](C8H4O4)·C8H6O4}n or {[Co(ttpe)(H2O)2](bdc)·(1,4-H2bdc)}n, (I), was synthesized by the hydrothermal method using 1,1,2,2-tetrakis[4-(1H-1,2,4-triazol-1-yl)phenyl]ethylene (ttpe), benzene-1,4-dicarboxylic acid (1,4-H2bdc) and Co(NO3)2·6H2O, and characterized by single-crystal X-ray diffraction, IR spectroscopy, powder X-ray diffraction (PXRD), luminescence, optical band gap and valence band X-ray photoelectron spectroscopy (VB XPS). Co-MOF (I) shows a (4,4)-connected binodal two-dimensional topology with a point symbol of {44·62}{44·62}. The two-dimensional networks capture free neutral 1,4-H2bdc molecules and bdc2- anions, and construct a three-dimensional supramolecular architecture via hydrogen-bond interactions. MOF (I) is a good photocatalyst for the degradation of methylene blue and rhodamine B under visible-light irradiation and can be reused at least five times.

7.
Acta Crystallogr C Struct Chem ; 75(Pt 8): 1053-1059, 2019 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-31380787

RESUMO

Metal-organic frameworks (MOFs) have attracted much interest in the fields of gas separation and storage, catalysis synthesis, nonlinear optics, sensors, luminescence, magnetism, photocatalysis gradation and crystal engineering because of their diverse properties and intriguing topologies. A Cu-MOF, namely poly[[(µ2-succinato-κ2O:O'){µ2-tris[4-(1,2,4-triazol-1-yl)phenyl]amine-κ2N:N'}copper(II)] dihydrate], {[Cu(C4H4O4)(C24H18N10)]·2H2O}n or {[Cu(suc)(ttpa)]·2H2O}n, (I), was synthesized by the hydrothermal method using tris[4-(1,2,4-triazol-1-yl)phenyl]amine (ttpa) and succinate (suc2-), and characterized by IR, powder X-ray diffraction (PXRD), luminescence, optical band gap and valence band X-ray photoelectron spectroscopy (VB XPS). Cu-MOF (I) shows a twofold interpenetrating 4-coordinated three-dimensional CdSO4 topology with point symbol {65·8}. It presents good photocatalytic degradation of methylene blue (MB) and rhodamine B (RhB) under visible-light irradiation. A photocatalytic mechanism was proposed and confirmed.

8.
Acta Crystallogr C Struct Chem ; 75(Pt 7): 960-968, 2019 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-31271385

RESUMO

Coordination polymers (CPs) have been widely studied because of their diverse and adjustable topologies and wide-ranging applications in luminescence, chemical sensors, magnetism, photocatalysis, gas adsorption and separation. In the present work, two coordination polymers, namely poly[(µ5-benzene-1,3,5-tricarboxylato-κ6O1:O1':O3:O3:O5,O5'){µ3-1,3-bis[(1,2,4-triazol-4-yl)methyl]benzene-κ3N:N':N''}di-µ3-hydroxido-dicobalt(II)], [Co2(C9H3O6)(OH)(C12H12N6)]n or [Co2(btc)(OH)(mtrb)]n, (1), and poly[[diaquabis(µ3-benzene-1,3,5-tricarboxylato-κ3O1:O3:O5)bis{µ3-1,3-bis[(1,2,4-triazol-4-yl)methyl]benzene-κ3N:N':N''}tetra-µ3-hydroxido-tetracopper(II)] monohydrate], {[Cu4(C9H3O6)2(OH)2(C12H12N6)2(H2O)2]·H2O}n or {[Cu4(btc)2(OH)2(mtrb)2(H2O)2]·H2O}n, (2), were synthesized by the hydrothermal method using 1,3-bis[(1,2,4-triazol-4-yl)methyl]benzene (mtrb) and benzene-1,3,5-tricarboxylate (btc3-). CP (1) exhibits a (3,8)-coordinated three-dimensional (3D) network of the 3,8T38 topological type, with a point symbol of {4,5,6}2{42·56·616·72·82}, based on the tetranuclear hydroxide cobalt(II) cluster [Co4(µ3-OH)2]. CP (2) shows a (3,8)-coordinated tfz-d topology, with a point symbol of {43}2{46·618·84}, based on the tetranuclear hydroxide copper(II) cluster [Cu4(µ3-OH)2]. The different (3,8)-coordinated 3D networks based on tetranuclear hydroxide-metal clusters of (1) and (2) are controlled by the different central metal ions [CoII for (1) and CuII for (2)]. The thermal stabilities and solid-state optical diffuse-reflection spectra were measured. The energy band gaps (Eg) obtained for (1) and (2) were 2.72 and 2.29 eV, respectively. CPs (1) and (2) exhibit good photocatalytic degradation of the organic dyes methylene blue (MB) and rhodamine B (RhB) under visible-light irradiation.

9.
Ultrason Sonochem ; 56: 213-228, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31101257

RESUMO

Four nanostructural nickel(II) coordination polymers {[Ni(ttpa)(1,4-ndc)(H2O)2]·2H2O}n (1), {[Ni(ttpa)(1,3-bda)]·2H2O·DMF}n (2·2H2O·DMF), {[Ni(ttpa)(1,4-bdc)]·H2O}n (3) and {[Ni(ttpa)(aip)(H2O)]·3H2O}n (4·3H2O) were synthesized using hydrothermal and sonochemical methods (ttpa = tris(4-(1,2,4-triazol-1-yl)phenyl)amine, 1,4-ndc = 1,4-naphthalenedicarboxylate, 1,3-bda = 1,3-benzenediacetate, 1,4-bdc = 1,4-benzenedicarboxylate, aip = 5-aminoisophthalate), and characterized by elemental analysis, IR spectra, scanning electron microscopy, single-crystal and powder X-ray diffraction analysis, optical band gaps, VB XPS spectra and luminescence. The effects of sonication power, time and frequency on the size and morphology of nano-sized 1-4 have been studied. 1 exhibits an unusual 2D + 2D → 3D inclined polycatenated motif based on the (3,3)-coordinated 63-hcb topology. 2 shows a (3,4)-coordinated 2D network of the bey topology. 3 presents a rare example of the 4-fold interpenetrating array of (3,5)-coordinated 3D network belonging to the 35T1 topology type. 4 displays an unusual 2D → 3D polythreaded network based on 2D sql networks. 1-4 exhibit luminescent emissions at 409, 399, 413 and 402 nm, respectively. 1-4 are semiconducting in nature, with Eg of 2.12 eV (1), 2.34 eV (2), 2.32 eV (3), and 2.47 eV (4). 1-4 are good catalysts for the degradation of MB under visible light irradiation. The effects of the size and morphology of nano-sized 1-4 on the photocatalytic efficiencies were studied. The higher sonication frequency obtains uniform and smaller nano-sized coordination polymers which have higher catalytic efficiencies.

10.
Spectrochim Acta A Mol Biomol Spectrosc ; 214: 372-377, 2019 May 05.
Artigo em Inglês | MEDLINE | ID: mdl-30802793

RESUMO

A copper(II) metal-organic framework {[Cu(ttpa)(pim)]·H2O}n (1) was synthesized and characterized by EA, IR, X-ray powder diffraction, optical band gaps, VB XPS spectra and luminescence (ttpa = tris(4-(1,2,4-triazol-1-yl)phenyl)amine, pim = pimelate). 1 exhibits the 3D pcu topology containing the [Cu2(COO)4] dimer building block. Eg, Ev and Ec of 1 were 2.37, 1.64 and -0.73 eV, respectively. MOF 1 exhibits a highly photocatalytic efficiency for the degradation of methylene blue and rhodamine B by visible light irradiation. The photocatalyst 1 is very stable after photocatalytic experiment and can be reused for at least five times. The photocatalytic mechanism was detailedly assumed and confirmed by the photocatalytic reaction in the presence of the hydroxyl radical scavenger mannitol and trapping agent 1,4-benzenedicarbolic acid.

11.
Dalton Trans ; 47(27): 9103-9113, 2018 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-29938730

RESUMO

A bifunctional cationic metal-organic framework {[Cu9(OH)6Cl2(itp)6(1,4-bdc)3](NO3)2(OH)2·20H2O}n (1-NO3-OH·20H2O) was synthesized and characterized (itp = 1-imidazol-1-yl-3-(1,2,4-triazol-4-yl)propane, 1,4-bdc = 1,4-benzenedicarboxylate). In 1-NO3-OH·20H2O, three [Cu3(µ3-OH)(µ2-OH)] trimeric clusters are bridged by two µ3-Cl and form a [Cu9(µ3-OH)3(µ2-OH)3(µ3-Cl)2] cluster. Such a nonanuclear copper(ii) cluster [Cu9(µ3-OH)3(µ2-OH)3(µ3-Cl)2] has not been reported till now, at least to the best of our knowledge. 1-NO3-OH·20H2O showed a 6-connected 2D 36-hxl net based on a nonanuclear copper(ii) cluster [Cu9(µ3-OH)3(µ2-OH)3(µ3-Cl)2]. 1-NO3-OH·20H2O is also the first 2D 36-hxl net-based nonanuclear cluster. 1-NO3-OH (guest-free phase) showed fast and highly efficient Cr2O72- and CrO42- trapping, and good recyclability for capturing Cr2O72- and CrO42-. The adsorption capacities of 1-NO3-OH to capture Cr2O72- and CrO42- were 1.762 mol mol-1 (154.8 mg g-1) and 1.896 mol mol-1 (89.5 mg g-1), respectively, at a molar ratio of 1 : 2 (1-NO3-OH to 2.5 × 10-3 mol L-1 Cr2O72- or CrO42-). 1-NO3-OH exhibited the selective sorption of Cr2O72- or CrO42- from a solution containing a mixture of Cr2O72- or CrO42- and a ten-fold molar amount of ClO4-, NO3-, Cl-, BF4- or a five-fold molar amount of mol L-1 SO42-. 1-NO3-OH could capture 87.9% dilute Cr2O72- or 91.8% dilute CrO42- at an equimolar 1-NO3-OH to 20 ppm Cr2O72- or CrO42-. 1-NO3-OH·20H2O exhibited a highly efficient photocatalytic degradation of the cationic organic dyes methylene blue (MB) and rhodamine B (RhB) under visible light irradiation, and was shown to be a good photocatalyst for photocatalytic degradation of the cationic organic dyes.

12.
J Agric Food Chem ; 66(22): 5574-5580, 2018 Jun 06.
Artigo em Inglês | MEDLINE | ID: mdl-29730925

RESUMO

The potential efficacy of sulforaphane in protecting alcohol-induced hepatic injury in vivo and its underlying mechanism were investigated. Male C57BL/6 mice were orally administrated with broccoli sprout extract (BSE) containing sulforaphane [7.6, 25.2, and 50.4 mg/kg of body weight (bw)] once a day for 14 days. At the 13th day, mice were challenged with alcohol (5 g/kg of bw) every 12 h for 3 times, which increased malondialdehyde (MDA) levels (4.44 ± 1.24 nmol/mg of protein, p < 0.01) in the liver. Our results showed that low-, medium-, and high-dose BSE markedly reversed the decrease of antioxidant capacity through enhancing glutathione (GSH) (2.07 ± 0.31 mg/g of protein, p < 0.05; 2.31 ± 0.32 mg/g of protein, p < 0.01; and 2.46 ± 0.21 mg/g of protein, p < 0.01), superoxide dismutase (SOD) (483.20 ± 62.76 units/mg of protein; 500.81 ± 49.82 units/mg of protein, p < 0.05; and 605.00 ± < 64.32 units/mg of protein, p < 0.01), glutathione peroxidase (GSH-Px) (318 ± 60.74 units/mg of protein; 400.67 ± 72.47 units/mg of protein, p < 0.01; and 394.72 ± 62.97 units/mg of protein, p < 0.01), and glutathione S-transferase (GST) (31.84 ± 6.34 units/mg of protein, p < 0.05; 30.34 ± 6.40 units/mg of protein, p < 0.05; and 38.08 ± 7.05 units/mg of protein, p < 0.01) in the liver. The protective actions are also associated activation of phase 2 enzymes via nuclear erythoriod-2-related factor 2 (Nrf2). The endoplasmic reticulum (ER)-stress-specific proteins, such as glucose-regulated protein 78 (GRP78), activating transcription factor 6, and protein kinase RNA (PKR)-like ER kinase (PERK), were also significantly attenuated by BSE. These results indicate that BSE protects the liver against alcohol challenge via upregulating antioxidant capacity and downregulating ER stress.


Assuntos
Brassica/química , Doença Hepática Induzida por Substâncias e Drogas/tratamento farmacológico , Doença Hepática Induzida por Substâncias e Drogas/metabolismo , Estresse do Retículo Endoplasmático/efeitos dos fármacos , Etanol/toxicidade , Extratos Vegetais/administração & dosagem , Animais , Doença Hepática Induzida por Substâncias e Drogas/etiologia , Doença Hepática Induzida por Substâncias e Drogas/genética , Chaperona BiP do Retículo Endoplasmático , Glutationa/metabolismo , Glutationa Peroxidase/metabolismo , Humanos , Fígado/efeitos dos fármacos , Fígado/metabolismo , Masculino , Malondialdeído/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Estresse Oxidativo/efeitos dos fármacos , Substâncias Protetoras/administração & dosagem , Superóxido Dismutase/metabolismo
13.
Dalton Trans ; 47(17): 6189-6198, 2018 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-29671848

RESUMO

A zinc(ii) coordination polymer {[Zn3(mtrb)3(btc)2]·3H2O}n (1) was synthesized and characterized (mtrb = 1,3-bis(1,2,4-triazole-4-ylmethyl)benzene, btc = 1,3,5-benzenetricarboxylate). The polymer 1 shows an unusual (3,4,4)-coordinated self-catenated 3D network with the point symbol of {63}2{62·82·102}{64·82}2. The polymer 1 is the first luminescent sensor for the detection of 2-amino-4-nitrophenol (ANP). The polymer 1 is also a good luminescence sensor for detection of TNP, 2,4-DNP, 4-NP, ANP and 2-NP in MeOH, particularly for TNP. The order of detection efficiency is TNP > 2,4-DNP > 4-NP > ANP > 2-NP. The polymer 1 also exhibits high sensitivity and selectivity as a luminescence sensor for the detection of Fe3+, Cr2O72- and CrO42- in aqueous solution. Our experiments showed that the presence of interfering ions had no significant effect on the sensing of Fe3+, Cr2O72- or CrO42- ions. The detection limits for TNP, ANP, Fe3+, Cr2O72- and CrO42- are 0.22 µM, 4.12 µM, 1.78 µM, 2.83 µM, and 4.52 µM, respectively. The luminescence sensor is stable and can be recycled for detection at least five times. The possible quenching mechanisms are discussed. The polymer 1 is also an effective photocatalyst for degradation of methylene blue (MB) under visible or UV light irradiation.

14.
Chem Commun (Camb) ; 53(11): 1860-1863, 2017 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-28111672

RESUMO

An unusual porous cationic metal-organic framework based on a tetranuclear hydroxy-copper(ii) cluster displays fast and highly efficient dichromate trapping through a single-crystal to single-crystal process.

15.
Dalton Trans ; 45(38): 15078-15088, 2016 Sep 27.
Artigo em Inglês | MEDLINE | ID: mdl-27722583

RESUMO

Three metal-organic frameworks (MOFs) {[Co4(OH)2(adc)6(H2O)5][Co2(OH)(btrb)]2·8H2O}n (1), {[Co4(OH)2(btrb)(nip)3(H2O)3]·4H2O}n (2·4H2O) and {[Co4(OH)2(btrb)(btc)2(H2O)2]·9H2O}n (3·9H2O) (btrb = 1,4-bis(1,2,4-triazol-4-ylmethyl)benzene, H2adc = 1,3-adamantanedicarboxylic acid, H2nip = 5-nitroisophthalic acid and H3btc = 1,3,5-benzenetricarboxylic acid) were synthesized by a hydrothermal method. 1 shows an unusual (3,4)-connected 2D network with a point symbol of (4·62)2(42·62·82) based on [Co4(µ3-OH)2] and [Co2(µ3-OH)] units. 2 is a 6-connected pcu topology based on the [Co4(µ3-OH)2] unit. 3 is a rare (3,8)-connected 3D framework with a rare point symbol of (4·5·6)2(42·56·616·72·82) based on the [Co4(µ3-OH)2] unit. The magnetic measurements reveal that 1-3 exhibit antiferromagnetic interactions between the adjacent cobalt(ii) centers. 1-3 are good photocatalysts for the degradation of methylene blue (MB). The 1,2-position nitrogen atoms of the 4-substituted 1,2,4-triazole ligand act as strong σ-donators to form a quite stable coordination quadrangle with two metal ions. The btrb ligand containing two 4-substituted 1,2,4-triazole rings is favorable to form tetranuclear metal units. By the regulation of the multicarboxylate ligands, the connection number of [Co4(µ3-OH)2] clusters increases from 4 in 1 to 6 in 2 and then 8 in 3. This work presents a novel but effective method to design and regulate the connection number (4, 6 and 8 connected in this work) of MOFs with 4-substituted 1,2,4-triazole and rigid multicarboxylate ligands.

16.
Int J Mol Sci ; 16(8): 20033-49, 2015 Aug 24.
Artigo em Inglês | MEDLINE | ID: mdl-26305246

RESUMO

L. paracasei subp. paracasei X12 was previously isolated from a Chinese traditional fermented cheese with anticancer activities and probiotic potential. Herein, the integral peptidoglycan (X12-PG) was extracted by a modified trichloroacetic acid (TCA) method. X12-PG contained the four representative amino acids Asp, Glu, Ala and Lys, and displayed the similar lysozyme sensitivity, UV-visible scanning spectrum and molecular weight as the peptidoglycan standard. X12-PG could induce the production of apoptotic bodies observed by transmission electron microscopy (TEM). X12-PG could significantly induced the translocation of calreticulin (CRT) and the release of high mobility group box 1 protein (HMGB1), the two notable hallmarks of immunogenic cell death (ICD), with the endoplastic reticulum (ER) damaged and subsequently intracellular [Ca(2+)] elevated. Our findings implied that X12-PG could induce the ICD of HT-29 cells through targeting at the ER. The present results may enlighten the prospect of probiotics in the prevention of colon cancer.


Assuntos
Antineoplásicos/isolamento & purificação , Antineoplásicos/farmacologia , Lactobacillus/química , Peptidoglicano/isolamento & purificação , Peptidoglicano/farmacologia , Apoptose , Cálcio/metabolismo , Calreticulina/metabolismo , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Neoplasias do Colo/metabolismo , Estresse do Retículo Endoplasmático/efeitos dos fármacos , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Proteína HMGB1/metabolismo , Células HT29 , Humanos
17.
Artigo em Inglês | MEDLINE | ID: mdl-25827762

RESUMO

Three position isomers 1,2-, 1,3-, 1,4-benzenedicarboxylate and 1,4-bis(1,2,4-triazol-4-yl)benzene were used to assembly zinc(II) coordination polymers {[Zn2(btx)0.5(1,2-bdc)2(H2O)]·H2O}n (1), {[Zn(btx)(1,3-bdc)]·2H2O·(DMF)}n (2) and {[Zn(btx)(1,4-bdc)]·3H2O}n (3). 1 is a (3,4,4,4)-connected two-dimensional network with point symbol (4(2)·6)(4(4)·6(2))(4(3)·6(2)·8)(4(2)·6·10(3)). 2 shows a two-dimensional (4,4) network. 3 exhibits a 5-fold interpenetrated three-dimensional diamondoid network. The structural versatility shows that the structures of coordination polymers can be tuned by the position isomers ligands. The luminescence and thermal stability were investigated.

18.
Dalton Trans ; 42(26): 9771-6, 2013 Jul 14.
Artigo em Inglês | MEDLINE | ID: mdl-23689914

RESUMO

An unusual copper(II) coordination polymer {[Cu(tmtz)(H2O)4][Cu2(tmtz)2(sip)2]·4H2O}n (1) (tmtz = 1,4-bis(1,2,4-triazol-1-ylmethyl)-2,3,4,5-tetramethylbenzene, sip = 5-sulfoisophthalate) is synthesized by the hydrothermal reaction. X-Ray structural analysis shows that 1 is comprised of two distinct and crystallographically independent polymeric motifs polythreading together. The first motif of 1 is an unusual (3,5)-connected 3D anionic network [Cu2(tmtz)2(sip)2]. The second motif in 1 is the [Cu(tmtz)(H2O)4]n 1D cationic chain. A polythreading array formed by a (3,5)-connected 3D anionic network and 1D cationic chains. The catalytic performance exhibits that 1 is active as a catalyst for the degradation of methyl orange. The thermal analysis is also observed.


Assuntos
Cobre/química , Compostos Organometálicos/química , Polímeros/química , Ânions/química , Catálise , Cátions/química , Cristalografia por Raios X , Modelos Moleculares , Estrutura Molecular , Compostos Organometálicos/síntese química
19.
Acta Crystallogr Sect E Struct Rep Online ; 68(Pt 3): m253-4, 2012 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-22412411

RESUMO

In the title three-dimensional coordination polymer, [Cd(N(3))(2)(C(8)H(10)N(4))](n), the coordination geometry around the Cd(II) atom is distorted octa-hedral. The Cd(II) atom is coordinated by two N atoms from two cis-positioned bridging 1,2-bis-(imidazol-1-yl)ethane (bime) ligands and four N atoms from four azide anions. Each azide ligand acts in an end-on bridging coordination mode. The azide ligands and Cd(II) atoms form a one-dimensional zigzag chain constructed from four-membered [Cd(N(3))(2)](n) metallacycles extending along the a axis. These inorganic chains are connected with four other chains via bridging bime ligands to form a three-dimensional coordination network.

20.
Acta Crystallogr Sect E Struct Rep Online ; 67(Pt 8): m1100-1, 2011 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-22090874

RESUMO

In the crystal structure of the title 1:2 adduct, [Zn(2)(NCS)(4)(C(4)H(8)N(4))(2)]·2[Zn(NCS)(2)(C(4)H(8)N(4))(2)] or (Ia)·2(Ib), each Zn(II) atom is coordinated in a distorted tetra-hedral geometry by four N atoms from two triazole rings of two 4-amino-3,5-dimethyl-1,2,4-triazole (admt) ligands and two NCS(-) ligands. In (Ia), double N(1):N(2)-bridging admt ligands connect two Zn(II) atoms, forming a dimer with a Zn(2)(admt)(2) six-membered metallacycle located on a crystallographic inversion center. In (Ib), the admt ligands exhibit monodentate N(1)-coordination modes. Weak N-H⋯N, N-H⋯S and C-H⋯S hydrogen bonds play an important role in the inter-molecular packing. The S and C atoms of two thiocyanato ligands are disordered over two sets of sites in ratios of 0.57 (3):0.43 (3) and 0.63 (3):0.37 (3), respectively.

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