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1.
J Environ Manage ; 351: 119738, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38061102

RESUMEN

Nitrogen (N) cycle is one of the most significant biogeochemical cycles driven by soil microorganisms on the earth. Exogenous humic substances (HS), which include composted-HS and artificial-HS, as a new soil additive, can improve the water retention capacity, cation exchange capacity and soil nutrient utilization, compensating for the decrease of soil HS content caused by soil overutilization. This paper systematically reviewed the contribution of three different sources of HS in the soil-plant system and explained the mechanisms of N transformation through physiological and biochemical pathways. HS convert the living space and living environment of microorganisms by changing the structure and condition of soil. Generally, HS can fix atmospheric and soil N through biotic and abiotic mechanisms, which improved the availability of N. Besides, HS transform the root structure of plants through physiological and biochemical pathways to promote the absorption of inorganic N by plants. The redox properties of HS participate in soil N transformation by altering the electron gain and loss of microorganisms. Moreover, to alleviate the energy crisis and environmental problems caused by N pollution, we also illustrated the mechanisms reducing soil N2O emissions by HS and the application prospects of artificial-HS. Eventually, a combination of indoor simulation and field test, molecular biology and stable isotope techniques are needed to systematically analyze the potential mechanisms of soil N transformation, representing an important step forward for understanding the relevance between remediation of environmental pollution and improvement of the N utilization in soil-plant system.


Asunto(s)
Sustancias Húmicas , Suelo , Sustancias Húmicas/análisis , Ecosistema , Plantas/metabolismo , Contaminación Ambiental , Nitrógeno/metabolismo
2.
Small ; 18(19): e2201510, 2022 05.
Artículo en Inglés | MEDLINE | ID: mdl-35388969

RESUMEN

The immoderate use of pesticides in the modern agricultural industry has led to the pollution of water resources and ultimately threatens the human body. Herein, two metal-organic frameworks (MOFs), namely {[Zn(tpt)2 ·2H2 O]}n (Zn1) and {[Zn2 (tpt)2 (bdc)]}n (Zn2), (Htpt = 5-[4(1H-1,2,4-triazol-1-yl)]phenyl-2H-tetrazole), respectively, are constructed as smart materials for visual and on-site detection of pesticides and their removal from water. The exposed nitrogen-rich sites and high chemical stability make Zn2 a self-assembly core to further fabricate MOF-on-MOF-sodium alginate (ZIF-8-on-Zn2@SA) composite by wrapping ZIF-8 on the outside surface. Inheriting the excellent fluorescent emission of Zn2, the rod-like ZIF-8-on-Zn2@SA module exhibits naked-eye detection of thiophanate-methyl (TM) in real fruits and vegetables with a broad linear range (10-100 × 10-6  m), a low limit of detection (LOD = 0.14 × 10-6  m), and satisfactory recoveries (98.30-102.70%). In addition, carbendazim (CBZ), the metabolite of TM after usage in crops, can be efficiently removed from water by the ZIF-8-on-Zn2@SA (qmax  = 161.8 mg g-1 ) with a high correlation coefficient (R2  > 0.99). Therefore, the portable ZIF-8-on-Zn2@SA sensing platform presents a promising candidate for monitoring and removal of pesticides, especially suitable for regions with serious pesticide environmental pollution.


Asunto(s)
Estructuras Metalorgánicas , Plaguicidas , Alginatos , Humanos , Hidrogeles , Plaguicidas/análisis , Agua
3.
Environ Res ; 212(Pt B): 113353, 2022 09.
Artículo en Inglés | MEDLINE | ID: mdl-35483409

RESUMEN

Controlling eutrophication requires satisfying stringent phosphorus concentration standards. Metal-based adsorbents can effectively remove excess phosphorus from water bodies and achieve ultra-low phosphorus concentration control for wastewater. This review focuses on the material properties and phosphorus removal mechanism of metal-based adsorbents (Fe, Al, Ca, Mg, La). There are significant differences in physical and chemical properties of different metal materials, due to the different preparation methods and synthetic materials. The main factors affecting phosphorus removal performance include particle size, crystal structure and pHPZC. Smaller particle size, more disordered crystal structure and higher pHPZC are more favorable for phosphorus removal. The main mechanism of phosphorus removal by metal-based adsorbents is ligand exchange, which makes it exhibit excellent adsorption capacity, fast kinetics and well selectivity for phosphate. In addition, in order to improve the phosphorus removal performance, the surface properties of the adsorbent (e.g., surface charge, surface area, and functional groups) can be effectively improved by dispersion of biochar carriers or combination of multiple metal materials. In further studies, we should improve the absorption capacity of the adsorbent under high pH conditions and the resistance to coexisting ion interference. Finally, in order to ensure the effective application of metal-based adsorbents in the phosphorus removal field, experimental scale should be expanded in future work to suit the actual water body conditions.


Asunto(s)
Contaminantes Químicos del Agua , Agua , Adsorción , Eutrofización , Concentración de Iones de Hidrógeno , Cinética , Metales , Fosfatos/química , Fósforo/química , Aguas Residuales , Contaminantes Químicos del Agua/análisis
4.
Environ Res ; 214(Pt 1): 113783, 2022 11.
Artículo en Inglés | MEDLINE | ID: mdl-35810808

RESUMEN

As the increase of global industrial activities, phosphate from industrial wastes such as sewage sludge has become one of the limiting factors for water eutrophication. Herein, lanthanum carbonate hydroxide (La(CO3)OH)/magnetite (Fe3O4) nanoparticles functionalized porous biochar (La/Fe-NBC) with high phosphate adsorption properties is synthesized through molten salt pyrolysis-coprecipitation-hydrothermal multi-step regulation, and further reveal the related processes and mechanisms. La(CO3)OH functions as active sites for phosphate adsorption, Fe3O4 imparts magnetic properties to the composite substance, also porous biochar (NBC) acts as the carrier to prevent the agglomeration of La(CO3)OH and Fe3O4 nanoparticles. The adsorption process of La/Fe-NBC for phosphate fits to the Pseudo-Second Order and Langmuir model, with the theoretical maximum adsorption capacity up to 99.46 mg P/g. And La/Fe-NBC possesses excellent magnetic field (14.50 emu/g), stability, and selectivity, which enables for efficient multiple recovery and reuse. Mechanistic studies have shown that ligand exchange (inner-sphere complexation) between phosphate and carbonate/hydroxyl groups of La(CO3)OH, and electrostatic attraction play the dominant roles during adsorption process, although susceptible to the solution pH. While co-precipitation is not influenced of pH conditions but with limited contribution to phosphate adsorption. This study may facilitate to optimize the synthesis design of phosphate multi-functional composites for low-carbon and sustainable treatment of industrial phosphate-containing wastes.


Asunto(s)
Nanopartículas de Magnetita , Contaminantes Químicos del Agua , Adsorción , Carbonatos , Carbón Orgánico , Cinética , Lantano , Fosfatos , Porosidad , Aguas del Alcantarillado , Agua
5.
Inorg Chem ; 60(14): 10387-10397, 2021 Jul 19.
Artículo en Inglés | MEDLINE | ID: mdl-34236850

RESUMEN

Metal-organic frameworks (MOFs)-based sensors for monitoring toxic substances in wastewater have attracted great attention due to the efficient and reliable performance. Here, we has synthesized two novel zinc-based MOFs [Zn(ttb)2(H2O)2]n (Zn1-ttb) and {[Zn(ttb)2]·0.5CH3CN}n (Zn2-ttb) through changing the polarity of reaction solvents and finally obtained target 2D MOF material [Zn(ttb)(bdc)0.5]n(Zn3-ttb-bdc) by successfully introducing an ancillary ligand H2bdc (Httb = 1-(triazo-1-ly)-4-(tetrazol-5-ylmethyl)benzene, H2bdc = 1,4-benzenedicarboxylic acid). As-prepared Zn3-ttb-bdc exhibits high water and chemical stability as well as excellent fluorescence property. Due to the -COOH binding sites from H2bdc, Zn3-ttb-bdc shows high sensitivity and a rapid luminescent response to a representative organic micropollutant trinitrophenol (TNP) and inorganic pollutants (Fe3+ and Cr2O72-) in wastewater. The mechanisms of multifunctional detection abilities of Zn3-ttb-bdc toward different types of pollutants are further studied. This work presents the structural design in preparing MOF materials for multifunctional detection performance, thus opening new perspectives for emerging MOF-based sensors as environmental monitors.

6.
ChemSusChem ; 17(4): e202301227, 2024 Feb 22.
Artículo en Inglés | MEDLINE | ID: mdl-37833827

RESUMEN

Hydrothermal humification technology for the preparation of artificial humic matters provides a new strategy, greatly promoting the natural maturation process. Iron, as a common metal, is widely used in the conversion of waste biomass; however, the influence of Fe3+ on hydrothermal humification remains unknown. In this study, FeCl3 is used to catalyze the hydrothermal humification of corn straw, and the influence of Fe3+ on the hydrothermal humification is explored by a series of characterization techniques. Results show that Fe3+ as the catalyst can promote the decomposition of corn straw, shorten the reaction time from 24 h to 6 h, and increase the yield from 6.77 % to 14.08 %. However, artificial humic acid (A-HA) obtained from Fe3+ -catalysis hydrothermal humification contains more unstable carbon and low amount of aromatics, resulting in a significantly decreased stability of the artificial humic acid. These results provide theoretical guidance for regulating the structure and properties of artificial humic acid to meet various maintenance needs.

7.
Research (Wash D C) ; 7: 0308, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38375103

RESUMEN

Fe (hydr)oxides have a substantial impact on the structure and stability of soil organic carbon (SOC) pools and also drive organic carbon turnover processes via reduction-oxidation reactions. Currently, many studies have paid much attention to organic matter-Fe mineral-microbial interactions on SOC turnover, while there is few research on how exogenous carbon addition abiotically regulates the intrinsic mechanisms of Fe-mediated organic carbon conversion. The study investigated the coupling process of artificial humic acid (A-HA) and Fe(hydr)oxide, the mechanism of inner-sphere ligands, and the capacity for carbon sequestration using transmission electron microscopy, thermogravimetric, x-ray photoelectron spectroscopy, and wet-chemical disposal. Furthermore, spherical aberration-corrected scanning transmission electron microscopy-electron energy loss spectroscopy and Mössbauer spectra have been carried out to demonstrate the spatial heterogeneity of A-HA/Fe (hydr)oxides and reveal the relationship between the increase in Fe-phase crystallinity and redox sensitivity and the accumulation of organic carbon. Additionally, the dynamics of soil structures on a microscale, distribution of carbon-iron microdomains, and the cementing-gluing effect can be observed in the constructing nonliving anthropogenic soils, confirming that the formation of stable aggregates is an effective approach to achieving organic carbon indirect protection. We propose that exogenous organic carbon inputs, specifically A-HA, could exert a substantial but hitherto unexplored effect on the geochemistry of iron-carbon turnover and sequestration in anoxic water/solid soils and sediments.

8.
Sci Total Environ ; 915: 169870, 2024 Mar 10.
Artículo en Inglés | MEDLINE | ID: mdl-38218478

RESUMEN

Phosphorus (P) leaching loss from farmland soils is one of the main causes of water eutrophication. Thus, effective methods must be developed to maintain sustainability in agricultural soils. Herein, we design artificial humic acid (A-HA) coated ferrihydrite (Fh) particles for fixing P in soil. The experiments in water and soil are successively conducted to explore the phosphate adsorption mechanism and soil P retention performance of A-HA coated ferrihydrite particles (A-Fh). Compared with unmodified ferrihydrite (Fh), the phosphate adsorption capacity of A-Fh is increased by 15 %, the phosphate adsorption speed and selectivity are also significantly improved. The ligand exchange, electrostatic attraction and hydrogen bonding are the dominant mechanisms of phosphate adsorption by A-Fh. In soil experiments, the addition of 2 % A-Fh increases the soil P retention performance from 0.15 to 0.7 mg/kg, and A-Fh are able to convert more phosphate adsorbed by itself into soil available P to improve soil fertility. Overall, this work highlights the importance of this a highly effective amendment for improving poor soils.

9.
Environ Pollut ; 327: 121588, 2023 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-37028787

RESUMEN

Salinization of cropland is one of the major abiotic stresses affecting global agricultural sustainability, posing a serious threat to agricultural productivity and food security. Application of artificial humic acid (A-HA) as plant biostimulants has been increasingly attracting farmers and researchers. However, its regulation of seed germination and growth under alkali stress has rarely received attention. The purpose of this study was to investigate the response of maize (Zea mays L.) seed germination and seedling growth after the addition of A-HA. The effects of A-HA on seed germination, seedling growth, chlorophyll contents and osmoregulation substance under black and saline soil conditions were studied by soaking maize in solutions with and without various concentrations of A-HA. Artificial humic acid treatments significantly increased the seed germination index and dry weight of seedlings. The effects of maize root in absence and presence of A-HA under alkali stress were also evaluated using transcriptome sequencing. GO and KEGG analyzes were performed on differentially expressed genes, and the reliability of transcriptome data was verified by qPCR analysis. Results showed that A-HA significantly activated phenylpropanoid biosynthesis, oxidative phosphorylation pathways and plant hormone signal transduction. Moreover, Transcription factor analysis revealed that A-HA induced the expression of several transcription factors under alkali stress which had a regulatory effect on the alleviation of alkali damage in the root system. Overall, our results suggested that soaking seeds with A-HA can alleviate alkali accumulation and toxicity in maize, constituting a simple and effective strategy to mitigate saline toxicity. These results will provide new insights for the application of A-HA in management to reduce alkali-caused crop loss.


Asunto(s)
Plantones , Zea mays , Sustancias Húmicas , Reproducibilidad de los Resultados , Germinación , Álcalis , Semillas
10.
ACS Appl Mater Interfaces ; 15(8): 11163-11174, 2023 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-36802472

RESUMEN

Excessive use of pesticides has brought about serious environmental risks worldwide that pose significant harm for human health. Herein, a series of metal-organic framework (MOF)-based gel capsules with a pitaya-like core-shell structure are constructed through a green polymerization strategy for pesticide detection and removal, namely ZIF-8/M-dbia/SA (M = Zn, Cd). Significantly, the ZIF-8/Zn-dbia/SA capsule exhibits sensitive detection of alachlor, a representative pre-emergence acetanilide pesticide, with a satisfactory detection limit of 0.23 µM. In addition, the MOF-based gel capsules can be extended to a universal visual platform for the noninvasive detection of pesticide residues with various MOFs, such as Eu-MOF, Tb-MOF, and Cu-MOF, and participating dye. Similar to pitaya, the ordered porous structure of MOF in ZIF-8/Zn-dbia/SA capsules offers cavity and open sites for removing pesticide from water with the maximum adsorption amount qmax of 61.1 mg·g-1 toward alachlor in a Langmuir model. Thereby, this work presents the universality of gel capsule self-assembly technologies, including the well-preserved visible fluorescence area and porosity of the different structurally diverse MOFs, offering an ideal strategy for water decontamination and food safety control fields.

11.
J Hazard Mater ; 435: 129070, 2022 08 05.
Artículo en Inglés | MEDLINE | ID: mdl-35650747

RESUMEN

Humic substances (HS) as representative natural organic matters and the most common organic compounds existing in the environment, has been applied to the treatment and remediation of environmental pollution. This review systematically introduces and summarizes the redox activity of HS for the remediation of environmental pollutants. For inorganic pollutants (such as silver, chromium, mercury, and arsenic), the redox reaction of HS can reduce their toxicity and mobilization, thereby reducing the harm of these pollutants to the environment. The concentration and chemical composition of HS, environmental pH, ionic strength, and competing components affect the degree and rate of redox reactions between inorganic pollutants and HS significantly. With regards to organic pollutants, HS has photocatalytic activity and produces a large number of reactive oxygen species (ROS) under the light which reacts with organic pollutants to accelerate the degradation of organic pollutants. Under the affection of HS, the redox of Fe(III) and Fe(II) can enhance the efficiency of Fenton-like reaction to degrade organic pollutants. Finally, the research direction of HS redox remediation of environmental pollution is prospected.


Asunto(s)
Contaminantes Ambientales , Restauración y Remediación Ambiental , Compuestos Férricos , Sustancias Húmicas/análisis , Oxidación-Reducción
12.
Food Chem ; 377: 132054, 2022 May 30.
Artículo en Inglés | MEDLINE | ID: mdl-35008021

RESUMEN

Pesticides have been emerged as major organic pollutants in environment, owing to widely spread and intrinsic high toxicity in agricultural productivity. Herein, we designed and synthesized a practicability and portable metal-organic framework (MOF) based composite beads MOF-alginate-Ca2+-polyacrylic acid (kgd-M1@ACPs) consist of biocompatible host material (sodium alginate) and fluorescent center with blue emission (where kgd-M1 stands for {[Cd(tbia)·H2O]·2H2O}n), which was further developed for high-efficiency and naked-eye 2,6-dichloro-4-nitroaniline (DCN) monitoring in fruits and vegetables. Significantly, the kgd-M1@ACPs shows obvious fluorescent quench towards toxic pesticide DCN with a low limit of detection (LOD) of 0.09 µM and high recovery from 98.08 to 104.37%. Moreover, the kgd-M1@ACPs also presents an excellent DCN adsorption ability. This work demonstrates that smart material kgd-M1@ACPs is expected to be a good candidate for detection and removal of DCN in real fruits and vegetables, which will present a broad prospect for monitoring and treating pesticides.


Asunto(s)
Estructuras Metalorgánicas , Plaguicidas , Alginatos , Frutas , Verduras
13.
ACS Appl Mater Interfaces ; 13(4): 5235-5244, 2021 Feb 03.
Artículo en Inglés | MEDLINE | ID: mdl-33470803

RESUMEN

Currently, Spiro-OMeTAD is the most widely used hole transport material (HTM) in the best-performing perovskite solar cells (PSCs), resulting from its suitable energy level and facile processing. However, the intrinsic properties of organic molecules, such as low conductivity and a nonpolar contact interface, will limit the power conversion efficiency (PCE) and stability of Spiro-OMeTAD-based PSCs. Chemical doping could be an effective strategy to ameliorate the performance of Spiro-OMeTAD, and most of the dopants are designed for controllably oxidizing Spiro-OMeTAD. In this work, a highly stable metal-organic framework {[Zn(Hcbob)]·(solvent)}n (Zn-CBOB) with rod topology and Lewis basic sites is assembled and employed as a dopant for the hole transport layer. It is found that Zn-CBOB not only controllably oxidizes Spiro-OMeTAD and improves the conductivity of the HTM but also passivates the surface traps of the perovskite film by coordinating with Pb2+. The Zn-CBOB-doped PSCs achieved a remarkable PCE of 20.64%. In addition, the hydrophobicity of Zn-CBOB can prevent water from destroying the perovskite layer, which helps elevate the stability of PSCs.

14.
ACS Appl Mater Interfaces ; 12(52): 58239-58251, 2020 Dec 30.
Artículo en Inglés | MEDLINE | ID: mdl-33345540

RESUMEN

It is very significant that functional porous metal-organic frameworks are used to manufacture hierarchical components to achieve cascading functions that cannot be achieved by a single-layer metal-organic framework (MOF). Here, we report two cases of novel MOFs constructed by the same ligand, Cu(I)-tpt and Cu(II)-tpt (Htpt = 5-[4(1H-1,2,4-triazol-1-yl)]phenyl-2H-tetrazole), and prepared a Cu(II)-tpt-on-Cu(I)-tpt membrane by a layer-by-layer approach ignoring the lattice mismatch problem. The first Cu(I)-tpt layer is grown on an oriented Cu2O nanostructured array by a "one-pot" approach. The aligned second Cu(II)-tpt layer can be deposited using liquid-phase epitaxy. Notably, the prepared Cu(II)-tpt-on-Cu(I)-tpt membrane combines adsorption and fluorescence sensing, which exhibited significant adsorption for Cr2O72- (203.25 mg g-1) as typical highly poisonous ions with a fluorescence quenching response. Hence, based on the oxidation-reduction between Cr2O72- and p-arsanilic acid (p-ASA), the Cu(II)-tpt-on-Cu(I)-tpt membrane's ability to adsorb Cr2O72- could be used to design "on-off-on" mode fluorescence probes to detect p-ASA with high sensitivity (limit of detection (LOD) = 0.0556 µg L-1). p-ASA can be degraded into highly toxic inorganic arsenic compounds in the natural environment and has received widespread attention. Therefore, the integration of adsorption and fluorescence properties makes the Cu(II)-tpt-on-Cu(I)-tpt membrane a feasible multifunctional material for pollution control and detection.

15.
ACS Appl Mater Interfaces ; 12(7): 8650-8662, 2020 Feb 19.
Artículo en Inglés | MEDLINE | ID: mdl-31951369

RESUMEN

Antibiotic contamination of water bodies is a major environmental concern. Exposure to superfluous antibiotics is an ecological stressor correlated to the development of antibiotic resistance. Thus, it is imperative that effective methods are developed to simultaneously detect and remove such antibiotics so as to avoid inadvertent release. Herein, two flexible three-dimensional (3D) zinc-based metal-organic frameworks (MOFs) {[Zn2(bcob)(OH)(H2O)]·DMA}n (ROD-Zn1) and {[Zn(Hbcob)]·(solvent)}n (ROD-Zn2) (H3bcob = 1,3-bis((4'-carboxylbenzyl)oxy)benzoic acid) with rod second building units (SBUs) are successfully prepared. Their exceptional water and chemical stabilities (toward both acid and base), fast sorption kinetics, and unique framework endow the MOFs with excellent uptake capacity toward various antibiotics in the aqueous environment. The adsorption performance was further optimized by one-pot preparation of MOF-melamine foam (MF) hybrid composites, resulting in a hierarchical microporous-macroporous MOF@MF system (ROD-Zn1@MF and ROD-Zn2@MF), which are readily recyclable after adsorptive capture. The mechanisms of adsorption have been deeply investigated by static and competitive adsorption experiments. In addition, the MOFs exhibit excellent fluorescent properties and quenched by trace amounts of antibiotics in water solution. Therefore, ROD-Zn1 and ROD-Zn2 present a dual-functional performance, being promising candidates for detection and removal of antibiotics.


Asunto(s)
Antibacterianos/química , Estructuras Metalorgánicas/química , Nanocompuestos/química , Contaminantes Químicos del Agua/química , Purificación del Agua/métodos , Compuestos de Zinc/química , Zinc/química , Adsorción , Fluorescencia , Cinética , Estructuras Metalorgánicas/ultraestructura , Microscopía Electrónica de Rastreo , Nanocompuestos/ultraestructura , Electricidad Estática , Triazinas/química , Agua/química , Difracción de Rayos X
16.
Chem Commun (Camb) ; 56(4): 631-634, 2020 Jan 14.
Artículo en Inglés | MEDLINE | ID: mdl-31833492

RESUMEN

A robust hafnium-based metal organic framework, Hf-PBTA, with sensitive and self-calibrating dual-emissive fluorescence response towards sulfite and sulfonic derivatives, including antibiotic sulfamethazine, has been developed, which shows fast detection of sulfite ions at a concentration as low as 76 ppb. The opposite response tendency from two radiative pathways towards aromatic sulfonic molecules and sulfite anions stems from the synergistic effect of the pyridine protonation effect, π-π stacking interaction and intramolecular twist motion.

17.
ACS Appl Mater Interfaces ; 11(39): 36081-36089, 2019 Oct 02.
Artículo en Inglés | MEDLINE | ID: mdl-31508936

RESUMEN

Anthrax spores have been a determining risk to human beings and animals across the world. As such, the qualitative monitoring toward dipicolinic acid (DPA), the unique biomarker of bacillus anthracis, is highly desired and being moved forward in health management. Herein, a breathing zeolite-like supramolecular assembly (ZSA), with the sra topology and 1D hexagon channel, is designed by controlling the bridging angle of the ditopic ligand after systematic analysis in topology. The solvent-dependent dynamic behavior is illustrated by powder X-ray diffraction and reflected in tunable luminescent emission based on solvent polarity parameters. According to the structural result and theoretical analysis, Eu3+ is anchored within the framework to form a ratiometric luminescent sensor successfully because of the abundant potential active site. After DPA addition, the resulting composite shows a sensitive and selective response in the linear range of 0-7.0 µM stemmed from absorbance energy-transfer emission and preferential coordination. The work we presented here may enrich the sensing platforms containing lanthanides and expand the potential application of ZSAs in clinical analysis.


Asunto(s)
Carbunco/diagnóstico , Bacillus anthracis , Europio/química , Mediciones Luminiscentes , Ácidos Picolínicos/análisis , Zeolitas/química , Biomarcadores
18.
Chem Asian J ; 14(13): 2291-2301, 2019 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-31063643

RESUMEN

In this study, two novel crystal materials pcp1 and pcp1-L have been synthesized successfully. The different conformations of the two crystals are mainly attributed to the introduction of the Schiff-base ligand L (L=(E)-4-methyl-N-((6-methoxypyridin-2-yl)methylene)aniline). Subsequently, pcp1 and pcp1-L composites have been firstly produced by a vacuum filtration method on various substrates (i.e., melamine foam, plastic mesh, carbon fiber cloth and glass cloth). The obtained robust composites show excellent performance in removing PMs owing to high ζ potential, microporous structure, large conjugation system and electron cloud-exposed metal center (DFT calculations) of pcp1 and pcp1-L. Particularly, pcp1-L@glass cloth with low pressure drop exhibits high thermal stability and high long-term reproducibility. Additionally, the high removal efficiency of pcp1-L@glass cloth towards particulate matters could also be maintained, even achieving >99.9 % in the car exhaust gas field test.

19.
ACS Appl Mater Interfaces ; 10(26): 22746-22756, 2018 Jul 05.
Artículo en Inglés | MEDLINE | ID: mdl-29877692

RESUMEN

Metal-organic frameworks (MOFs), as drug delivery carriers, with high loading capacity and controllable release behavior can provide a more efficacious therapy in cancer treatments. In our work, a novel biocompatible zinc MOF Zn-cpon-1 with the (3,6)-connected rtl 3D topological network was designed and synthesized via employing ClO4- anion as template. The optically and chemically stable Zn-cpon-1 could be verified as a pH-responsive dual-emission platform and excellent drug delivery carrier with higher 5-fluorouracil (5-FU) (44.75 wt %) loading behavior than 6-mercaptopurine (6-MP) (4.79 wt %) ascribed to the influence of size and shape matching. The multiple interactions between Zn-cpon-1 and 5-FU drug molecules have been discussed and evidenced, which could be quantitatively estimated via the rate constant related to the topological structure. Specially, the gust release behavior of 5-FU@Zn-cpon-1 microcrystal was described and programmed via the Weibull distribution model and could be dual-triggered by the temperature and pH stimulus. This study illustrates that the Zn-cpon-1 without any postmodification performs a favorable potential of being used as biomedical drug delivery alternative carriers in effective drug payload, flexible release administration, and superior dual-stimuli responsiveness.

20.
PLoS One ; 11(3): e0151414, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-26977697

RESUMEN

To correct the incongruence of document types between the numerator and denominator in the traditional impact factor (IF), we make a corresponding adjustment to its formula and present five corrective IFs: IFTotal/Total, IFTotal/AREL, IFAR/AR, IFAREL/AR, and IFAREL/AREL. Based on a survey of researchers in the fields of ophthalmology and mathematics, we obtained the real impact ranking of sample journals in the minds of peer experts. The correlations between various IFs and questionnaire score were analyzed to verify their journal evaluation effects. The results show that it is scientific and reasonable to use five corrective IFs for journal evaluation for both ophthalmology and mathematics. For ophthalmology, the journal evaluation effects of the five corrective IFs are superior than those of traditional IF: the corrective effect of IFAR/AR is the best, IFAREL/AR is better than IFTotal/Total, followed by IFTotal/AREL, and IFAREL/AREL. For mathematics, the journal evaluation effect of traditional IF is superior than those of the five corrective IFs: the corrective effect of IFTotal/Total is best, IFAREL/AR is better than IFTotal/AREL and IFAREL/AREL, and the corrective effect of IFAR/AR is the worst. In conclusion, not all disciplinary journal IF need correction. The results in the current paper show that to correct the IF of ophthalmologic journals may be valuable, but it seems to be meaningless for mathematic journals.


Asunto(s)
Factor de Impacto de la Revista , Algoritmos , Matemática , Oftalmología , Publicaciones Periódicas como Asunto/clasificación , Publicaciones Periódicas como Asunto/estadística & datos numéricos , Encuestas y Cuestionarios , Estados Unidos
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