Publications by authors named "Xin-Le Li"

7 Publications

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An unprecedented 2D covalent organic framework with an htb net topology.

Chem Commun (Camb) 2019 Nov 24;55(89):13454-13457. Epub 2019 Oct 24.

School of Chemistry, South China Normal University, Guangzhou 510006, P. R. China.

A 2D imine-linked COF with a hitherto unreported htb type topology was synthesized from a linear diamine linker and a judiciously designed tetra-aldehyde building block. This work opens the door to the development of COFs with unprecedented topologies and may broaden the scope of COF functional materials by pore size and pore surface engineering.
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http://dx.doi.org/10.1039/c9cc06780aDOI Listing
November 2019

[Effects of long-term rainfall addition on the morphological characteristics and point pattern of desert plants].

Ying Yong Sheng Tai Xue Bao 2019 Oct;30(10):3367-3375

Experimental Center of Desert Forestry, Chinese Academy of Forestry, Dengkou 015200, Inner Mongolia, China.

Studying the effects of rainfall change on morphological characteristics, spatial pattern and spatial correlation of desert dominant plants could help to predict the response of desert ecosystem to global climate change. We conducted a 10-year simulated rainfall addition experiment and examined the morphological characteristics, spatial pattern and spatial correlation of typical desert plant species, Nitraria tangutorum and Artemisia ordosica, under long-term simulated rainfall enhancement conditions in Ulanbuh desert, using Programita software, Ripley's K function, and Monte Carlo method. The results showed that there were significant differences in the number, height, average crown and base diameter of the desert plants under different treatments. The number, height, average crown and base diameter of N. tangutorum and A. ordosica were significantly larger than CK, all of which increased with the amount of rainfall. When the amount of rainfall addition was less than 72 mm, the branch of N. tangutorum showed cluster distribution. When it was larger than 72 mm, it showed a tendency to decrease the aggregation intensity with rainfall increasing. The spatial distribution of A. ordosica population was characterized by random distribution-cluster distribution-random distribution pattern with rainfall increasing. In terms of spatial association, branch of N. tangutorum and A. ordosica showed negative correlation under control, but no correlation or positive correlation with rainfall increasing. When the amount of rainfall increased to 144 mm, the spatial association between two species changed from negative to positive. Under the scenario of increasing rainfall, soil moisture was improved, which would lead to a positive correlation between species and be more conducive to the coexistence and growth of N. tangutorum and A. ordosica.
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http://dx.doi.org/10.13287/j.1001-9332.201910.013DOI Listing
October 2019

Stable Hydrazone-Linked Covalent Organic Frameworks Containing O,N,O'-Chelating Sites for Fe(III) Detection in Water.

ACS Appl Mater Interfaces 2019 Apr 22;11(13):12830-12837. Epub 2019 Mar 22.

School of Chemistry and Environment , South China Normal University , Guangzhou 510006 , P. R. China.

Two stable crystalline hydrazone-linked covalent organic frameworks (COFs) (Bth-Dha and Bth-Dma) containing functional O,N,O'-chelating sites have been designed and successfully synthesized by the Schiff-base condensation reactions between benzene-1,3,5-tricarbohydrazide (Bth) and 2,5-dihydroxyterephthalaldehyde (Dha) or 2,5-dimethoxyterephthal-aldehyde (Dma), respectively. Bth-Dma exhibits strong fluorescence in the solid state and in an aqueous dispersion, while no fluorescence can be observed for Bth-Dha. Interestingly, the as-synthesized Bth-Dma can be used as a turn-off fluorescence sensor for the Fe(III) ion in aqueous solution with outstanding selectivity and sensitivity. The recognition process can be attributed to the coordination interaction between Fe(III) ion and the O,N,O'-chelating sites in the pore wall of Bth-Dma COF, as verified by X-ray photoelectron spectroscopy and H NMR spectroscopy. To the best of our knowledge, this is the first report on the rational design of luminescent COF with predesigned O,N,O'-chelating sites as a fluorescence sensor for highly selective and sensitive metal ion detection. This work may pave the way for designing luminescent COF sensors with functional binding sites for detecting specific metal ions.
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http://dx.doi.org/10.1021/acsami.9b02640DOI Listing
April 2019

SiO2 nanoparticles change colour preference and cause Parkinson's-like behaviour in zebrafish.

Sci Rep 2014 Jan 22;4:3810. Epub 2014 Jan 22.

State Key Laboratory of Medicinal Chemical Biology, College of Life Science, Nankai University, Tianjin 300071, China.

With advances in the development of various disciplines, there is a need to decipher bio-behavioural mechanisms via interdisciplinary means. Here, we present an interdisciplinary study of the role of silica nanoparticles (SiO2-NPs) in disturbing the neural behaviours of zebrafish and a possible physiological mechanism for this phenomenon. We used adult zebrafish as an animal model to evaluate the roles of size (15-nm and 50-nm) and concentration (300 μg/mL and 1000 μg/mL) in SiO2-NP neurotoxicity via behavioural and physiological analyses. With the aid of video tracking and data mining, we detected changes in behavioural phenotypes. We found that compared with 50-nm nanosilica, 15-nm SiO2-NPs produced greater significant changes in advanced cognitive neurobehavioural patterns (colour preference) and caused potentially Parkinson's disease-like behaviour. Analyses at the tissue, cell and molecular levels corroborated the behavioural results, demonstrating that nanosilica acted on the retina and dopaminergic (DA) neurons to change colour preference and to cause potentially Parkinson's disease-like behaviour.
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http://dx.doi.org/10.1038/srep03810DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3898208PMC
January 2014

Nickel-catalyzed triarylamine synthesis: synthetic and mechanistic aspects.

Org Biomol Chem 2014 Feb;12(8):1232-6

Beijing National Laboratory for Molecular Sciences (BNLMS), Key Laboratory of Green Printing, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, P. R. China.

An improved protocol was described for the amination of chloroarenes with diarylamines under NiCl2(PCy3)2 catalysis in the presence of a Grignard reagent as base. This method fully suits bromo-/iodoarene substrates as well, and even is expanded to certain aryl tosylates. A preliminary investigation into the mechanism suggests that this amination reaction might proceed through Ni(I) and Ni(III) intermediates rather than via the usually expected Ni(0)-Ni(II) cycle.
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http://dx.doi.org/10.1039/c3ob42053aDOI Listing
February 2014

[The genetic screening of a dominant zebrafish mutant in long-term memory].

Zhongguo Ying Yong Sheng Li Xue Za Zhi 2013 Jan;29(1):72-6

Key Laboratory of Animal Models and Degenerative Neurological Diseases, Nankai University School of Medicine, Tianjin 300071, China.

Objective: To screen the learning and memory mutant from N-ethyl-N-nitrosourea (ENU) mutagenic zebrafish F1, and to get the new model animal to study the mechanism of learning and memory.

Methods: Zebrafish mutant was screened by inhibitory avoidance behavioral test and identified by the expression of gene c-fos with qRT-PCR.

Results: We isolated a zebrafish mutant related to learning and memory, fgt. In this fgt zebrafish mutant long-term memory was much lower than that in wild-type when tested at 24 h after training. The 24 h long-term memory in about half of fgt mutant F2 (13/30) were significantly lower than those in wild-type, and the others relatively normal. Compared with the expression in wild-type fishes, the expression of immediate-early genes (IEGs) c-fos in half of fgt mutant F2 (13/30) after exploring in a novel environment increased distinctly from the basal control levels statistically, and the others relatively normal, which were in accordance with the behavioral results.

Conclusion: The zebrafish mutant fgt is a dominant mutant with defect in long-term memory.
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January 2013

Iron(III)-promoted oxidative coupling of naphthylamines: synthetic and mechanistic investigations.

Org Lett 2011 Sep 25;13(18):4950-3. Epub 2011 Aug 25.

Beijing National Laboratory for Molecular Sciences (BNLMS), Laboratory of New Materials, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, China.

A facile route to the synthesis of 1,1'-binaphthyl-4,4'-diamines (naphthidines) and 1,1'-binaphthyl-2,2'-diamines (BINAMs) was developed by the oxidative homocoupling of 1- and 2-naphthylamines, respectively, using FeCl(3) as oxidant and K(2)CO(3) as base in 1,2-dichloroethane under ambient conditions. A preliminary mechanistic investigation was performed by the ESR spectroscopy and intermediate-trapping technique.
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http://dx.doi.org/10.1021/ol202058rDOI Listing
September 2011