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1.
Angew Chem Int Ed Engl ; 63(18): e202401754, 2024 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-38380833

RESUMO

The one-step efficient separation of high-purity C2H4 from C2H4/C2H6 mixtures by hydrogen-bonded organic frameworks (HOFs) faces two problems: lack of strategies for constructing stable pores in HOFs and how to obtain high C2H6 selectivity. Herein, we have developed a microporous Mortise-Tenon-type HOF (MTHOF-1, MT is short for Mortise-Tenon structure) with a new self-assembly mode for C2H4/C2H6 separation. Unlike previous HOFs which usually possess discrete head-to-head hydrogen bonds, MTHOF-1 is assembled by unique consecutive side-by-side hydrogen bonds, which result in mortise-and-tenon pores decorated with orderly arranged amide groups and benzene rings. As expected, MTHOF-1 exhibits excellent stability under various conditions and shows clear separation trends for C2H6/C2H4. The IAST selectivity is as high as 2.15 at 298 K. More importantly, dynamic breakthrough experiments have demonstrated that MTHOF-1 can effectively separate the C2H6/C2H4 feed gas to obtain polymer-grade C2H4 in one step even under high-humidity conditions.

2.
Inorg Chem ; 61(19): 7530-7536, 2022 May 16.
Artigo em Inglês | MEDLINE | ID: mdl-35511047

RESUMO

The separation of C2-C3 alkyne/alkene mixtures is important but difficult work thanks to their similar physical and chemical properties. Crystalline porous materials with high alkyne adsorption and prominent separation selectivity of alkyne/alkene mixtures have been extensively investigated because of their energy-saving merits. Herein, we report a fluorinated hybrid microporous material (FJI-W1) that exhibits unexpected water and thermal stability. Gas sorption isotherms show that FJI-W1 has ultrahigh C2H2 and C3H4 adsorption capacities of 150 and 159 cm3/g, respectively. Furthermore, dynamic breakthrough experiments indicate that the intervals of breakthrough time between the two gases for 1:99 (v/v) C2H2/C2H4 and 1:99 (v/v) C3H4/C3H6 can be up to 230 and 600 min/g, respectively. Additionally, the tests with different flow rates and three-cycle breakthrough tests demonstrate that FJI-W1 has a remarkable C2-C3 alkyne/alkene separation performance.

3.
Int J Mol Sci ; 18(12)2017 Dec 11.
Artigo em Inglês | MEDLINE | ID: mdl-29232909

RESUMO

Water retaining agent (WRA) is widely used for soil erosion control and agricultural water saving. Here, we evaluated the effects of the combination of beneficial soil bacterium Bacillus amyloliquefaciens strain GB03 and WRA (the compound is super absorbent hydrogels) on drought tolerance of perennial ryegrass (Lolium perenne L.). Seedlings were subjected to natural drought for maximum 20 days by stopping watering and then rewatered for seven days. Plant survival rate, biomass, photosynthesis, water status and leaf cell membrane integrity were measured. The results showed that under severe drought stress (20-day natural drought), compared to control, GB03, WRA and GB03+WRA all significantly improved shoot fresh weight, dry weight, relative water content (RWC) and chlorophyll content and decreased leaf relative electric conductivity (REC) and leaf malondialdehyde (MDA) content; GB03+WRA significantly enhanced chlorophyll content compared to control and other two treatments. Seven days after rewatering, GB03, WRA and GB03+WRA all significantly enhanced plant survival rate, biomass, RWC and maintained chlorophyll content compared to control; GB03+WRA significantly enhanced plant survival rate, biomass and chlorophyll content compared to control and other two treatments. The results established that GB03 together with water retaining agent promotes ryegrass growth under drought conditions by improving survival rate and maintaining chlorophyll content.


Assuntos
Bacillus amyloliquefaciens/fisiologia , Clorofila/metabolismo , Hidrogéis/farmacologia , Lolium/crescimento & desenvolvimento , Microbiologia do Solo , Biomassa , Secas , Lolium/metabolismo , Malondialdeído/metabolismo , Fotossíntese , Folhas de Planta/metabolismo , Estresse Fisiológico/efeitos dos fármacos , Água
4.
J Neuroinflammation ; 11: 41, 2014 Mar 04.
Artigo em Inglês | MEDLINE | ID: mdl-24594021

RESUMO

BACKGROUND: Depression has most often been diagnosed in patients with temporal lobe epilepsy (TLE), but the mechanism underlying this association remains unclear. In this study, we report that indoleamine 2,3-dioxygenase 1 (IDO1), a rate-limiting enzyme in tryptophan metabolism, plays a key role in epilepsy-associated depressive-like behavior. METHODS: Rats which develop chronic epilepsy following pilocarpine status epilepticus exhibited a set of interictal disorders consistent with depressive-like behavior. Changes of depressive behavior were examined by taste preference test and forced swim test; brain IL-1ß, IL-6 and IDO1 expression were quantified using real-time reverse transcriptase PCR; brain kynurenine/tryptophan and serotonin/tryptophan ratios were analyzed by liquid chromatography-mass spectrometry. Oral gavage of minocycline or subcutaneous injection of 1-methyltryptophan (1-MT) were used to inhibite IDO1 expression. RESULTS: We observed the induction of IL-1ß and IL-6 expression in rats with chronic TLE, which further induced the upregulation of IDO1 expression in the hippocampus. The upregulation of IDO1 subsequently increased the kynurenine/tryptophan ratio and decreased the serotonin/tryptophan ratio in the hippocampus, which contributed to epilepsy-associated depressive-like behavior. The blockade of IDO1 activation prevented the development of depressive-like behavior but failed to influence spontaneous seizures. This effect was achieved either indirectly, through the anti-inflammatory tetracycline derivative minocycline, or directly, through the IDO antagonist 1-MT, which normalizes kynurenine/tryptophan and serotonin/tryptophan ratios. CONCLUSION: Brain IDO1 activity plays a key role in epileptic rats with epilepsy-associated depressive-like behavior.


Assuntos
Depressão/etiologia , Depressão/patologia , Epilepsia do Lobo Temporal/complicações , Hipocampo/enzimologia , Indolamina-Pirrol 2,3,-Dioxigenase/metabolismo , Animais , Cromatografia Líquida , Citocinas/metabolismo , Depressão/tratamento farmacológico , Modelos Animais de Doenças , Epilepsia do Lobo Temporal/induzido quimicamente , Epilepsia do Lobo Temporal/tratamento farmacológico , Preferências Alimentares , Regulação da Expressão Gênica/efeitos dos fármacos , Hipocampo/patologia , Cloreto de Lítio/toxicidade , Masculino , Espectrometria de Massas , Minociclina/uso terapêutico , Ratos , Ratos Wistar , Estatísticas não Paramétricas , Fatores de Tempo , Triptofano/análogos & derivados , Triptofano/metabolismo , Triptofano/uso terapêutico
5.
ACS Appl Mater Interfaces ; 16(1): 1179-1186, 2024 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-38157244

RESUMO

Recently, methanol-to-olefins (MTO) technology has been widely used. The development of new adsorbents to separate MTO products and obtain high-purity ethylene (C2H4) and propylene (C3H6) has become an urgent task. Herein, an exceptionally highly water-stable metal-organic framework (MOF), [Cu3(OH)2(Me2BPZ)2]·(solvent)x (1) (H2Me2BPZ = 3,3'-dimethyl-1H,1'H-4,4'-bipyrazole) with hexagonal pores, has been elaborately designed and constructed. After being soaked in water for 7 days, it still maintains its structure, and the uptake of N2 at 77 K is unchanged. The adsorption capacity of C3H6 can reach 138 cm3 g-1, while the uptake of C2H4 is only 52 cm3 g-1 at 298 K and 1 bar. The dynamic breakthrough experiments show that the mixture of C3H6/C2H4 (50/50, v/v) can be efficiently separated in one step. High-purity C2H4 and C3H6 can be obtained through an adsorption and desorption cycle and the yields of C2H4 (purity ≥ 99.95%) and C3H6 (purity ≥ 99%) are 84 and 48 L kg-1, respectively. Surprisingly, when the flow rate is increased, the separation performance has no obvious change. Additionally, humidity has no effect on the separation performance. Finally, theoretical simulations indicate that there are stronger interactions between the C3H6 molecule and the framework, which are beneficial to capturing C3H6 over C2H4.

6.
ChemSusChem ; 16(7): e202202305, 2023 Apr 06.
Artigo em Inglês | MEDLINE | ID: mdl-36625243

RESUMO

Recently, metal-organic frameworks (MOFs) as the cathode materials for aqueous zinc-ion batteries (ZIBs) received growing attention. Herein, a novel MOF, Ni-Ndi-trz (Ndi-trz=2,7-di(4H-1,2,4-triazol-4-yl)benzo[lmn][3,8]phenanthroline-1,3,6,8(2H,7H)-tetraone) was synthesized through a solvothermal method. Its rational design using a naphthalene diimide (Ndi) core allowed the formation of a four-fold interpenetrated pcu (primitive cubic) topology. The as-synthesized Ni-Ndi-trz is highly stable over a wide pH range (0-12) for 30 days, which is critical to ensure the decent cyclability of zinc-ion batteries (ZIBs). When used as the cathode material of ZIBs, it shows a high initial specific capacity of 90.7 mAh g-1 and excellent cycling stability. Remarkably, three-electrode system tests, ex situ FTIR, UV/Vis and XPS spectra revealed that the Ndi core of Ni-Ndi-trz undergoes a reversible interconversion between the keto and enol forms when interacting with Zn2+ ions. This work may shed light on the feasibility of designing novel MOFs and exploring their mechanisms for zinc ion batteries.

7.
ACS Appl Mater Interfaces ; 14(46): 52216-52222, 2022 Nov 23.
Artigo em Inglês | MEDLINE | ID: mdl-36356232

RESUMO

Considering the importance of C2H2 in industry, it is of great significance to develop porous materials for efficient C2H2/CO2 separation. Besides the high selectivity, the C2H2 adsorption capacity is another vital factor in C2H2/CO2 separation. However, the "trade-off" between these two factors is still perplexing. Rational pore design of metal-organic frameworks (MOFs) has been proven to be an effective way to solve the above problem. In this work, we have appropriately combined three kinds of strategies in the design of the MOF (FJI-H33), i.e., the introduction of open metal sites, construction of cage-like cavities, and adjustment of moderate pore size. As anticipated, FJI-H33 exhibits both outstanding C2H2 adsorption capacity and high C2H2/CO2 selectivity. At 298 K and 100 kPa, the C2H2 storage capacity of FJI-H33 is 154 cm3/g, while the CO2 uptake is only 80 cm3/g. The ideal adsorbed solution theory (IAST) selectivity of C2H2/CO2 (50:50) is calculated as high as 15.5 at 298 K. More importantly, the excellent practical separation performance was verified by breakthrough experiments. In addition, the calculation of adsorption sites and relevant energy by density functional theory (DFT) provides a good explanation for the excellent separation performance and pore design strategy.

8.
ACS Omega ; 5(16): 9540-9549, 2020 Apr 28.
Artigo em Inglês | MEDLINE | ID: mdl-32363306

RESUMO

This paper adopts the measurement of mercury intrusion porosimetry and nuclear magnetic resonance (NMR) to analyze the pore system and the pore structure of coal samples, and the measurement of maceral group composition, scanning electron microscopy, and energy dispersive X-ray spectroscopy to obtain the organic/inorganic composition of coal samples. Gravimetric and NMR methods are both used to calculate irreducible water saturation of the samples, and qualitative and quantitative research studies are therefore conducted. The following knowledge is obtained. Coal samples can be classified as micro-trans-pore-dominated samples, meso-macro-pore-dominated samples, cleat-dominated samples, and even development samples. The main composition of the samples is organic, and a little kaolinite and pyrite can be observed. Irreducible water saturation obtained by the gravimetric method is almost close to that gained by the NMR method. The influencing parameters can be divided into two categories. The first category contains the maximum vitrinite reflectance, volumetric factor, fixed carbon yield, volatile yield, vitrinite percentage, and inertinite percentage, which have a strong correlation with irreducible water saturation. The second category includes the buried depth and median radius, and they have a weak correlation with irreducible water saturation. Multivariate regression shows that there is a linear quaternion equation between irreducible water saturation and independent variables such as maximum vitrinite reflectance, volumetric factor, volatile yield, and vitrinite percentage.

9.
Genes (Basel) ; 10(3)2019 03 13.
Artigo em Inglês | MEDLINE | ID: mdl-30871275

RESUMO

Genomic data is a powerful tool. However, the phylogenetic relationships among different ecological races of avocado remain unclear. Here, we used the results from specific length amplified fragment sequencing (SLAF-seq) and transcriptome data to infer the population structure and genetic diversity of 21 avocado cultivars and reconstructed the phylogeny of three ecological races and two interracial hybrids. The results of the three analyses performed (unweighted pair-group methods with arithmetic means (UPGMA) cluster, Principal coordinate analysis (PCoA), and STRUCTURE) based on single nucleotide polymorphisms (SNPs) from SLAF-seq all indicated the existence of two populations based on botanical race: Mexican⁻Guatemalan and West Indian genotype populations. Our results based on SNPs from SLAF-seq indicated that the Mexican and Guatemalan races were more closely related to each other than either was to the West Indian race, which also was confirmed in the UPGMA cluster results based on SNPs from transcriptomic data. SNPs from SLAF-seq provided strong evidence that the Guatemalan, Mexican, and Guatemalan × Mexican hybrid accession possessed higher genetic diversity than the West Indian races and Guatemalan × West Indian hybrid accessions. Six race-specific Kompetitive allele specific PCR (KASP) markers based on SNPs from SLAF-seq were then developed and validated.


Assuntos
Persea/genética , Polimorfismo Genético , Transcriptoma , Marcadores Genéticos , Técnicas de Genotipagem/métodos , Técnicas de Genotipagem/normas , Persea/classificação , Filogenia , Banco de Sementes
10.
Mycology ; 9(3): 223-232, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30181928

RESUMO

Powdery mildew caused by Erysiphe pisi is a major factor that affects the growth of standing milkvetch (Astragalus adsurgens). As arbuscular mycorrhizal fungi (AMF) have shown to be enhancing the resistance of plants to biotrophic pathogens such as powdery mildew, a study was carried out to look at the effects of three AMF, either singularly or in combination, on the growth of standing milkvetch and susceptibility to E. pisi. The results showed that the presence of AMF enhanced the growth of standing milkvetch even though their presence in the roots increased susceptibility to this foliage pathogen compared with plants having no AMF. This increase in growth of plants with severe infection of powdery mildew was especially surprising as leaves contained lower levels of chlorophyll than plants without AMF and had a greater concentration of malondialdehyde, an indicator of the damage of cell membrane. The effects on the extent of growth and powdery mildew enhancement differed inconsistently with the type of AMF in roots. The effects on growth and powdery mildew were not related to intensity of AMF colonisation. The peroxidase (POD) was consistently higher activity (15% to 72%) in plants with AMF than plants without them.

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