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1.
Nanomaterials (Basel) ; 14(12)2024 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-38921936

RESUMO

In recent years, microplastics (MPs) have emerged as a significant environmental pollutant, garnering substantial attention for their migration and transformation behaviors in natural environments. MPs frequently infiltrate natural porous media such as soil, sediment, and rock through various pathways, posing potential threats to ecological systems and human health. Consequently, the migration and adsorption mechanisms applied to MPs in porous media have been extensively studied. This paper aims to elucidate the migration mechanisms of MPs in porous media and their influencing factors through a systematic review. The review encompasses the characteristics of MPs, the physical properties of porous media, and hydrodynamic factors. Additionally, the paper further clarifies the adsorption mechanisms of MPs in porous media to provide theoretical support for understanding their environmental behavior and fate. Furthermore, the current mainstream detection techniques for MPs are reviewed, with an analysis of the advantages, disadvantages, and applications of each technique. Finally, the paper identifies the limitations and shortcomings of current research and envisions future research directions.

2.
Vet Sci ; 11(6)2024 Jun 09.
Artigo em Inglês | MEDLINE | ID: mdl-38922013

RESUMO

Platelet-derived growth factor B (PDGFB), as an important cellular growth factor, is widely involved in the regulation of cellular events such as cell growth, proliferation, and differentiation. Although important, the expression characteristics and biological functions in the mammalian reproductive system remain poorly understood. In this study, the PDGFB gene of Tibetan sheep was cloned by RT-PCR, and its molecular characteristics were analyzed. Subsequently, the expression of the PDGFB gene in the testes and epididymides (caput, corpus, and cauda) of Tibetan sheep at different developmental stages (3 months, 1 year, and 3 years) was examined by qRT-PCR and immunofluorescence staining. A bioinformatic analysis of the cloned sequences revealed that the CDS region of the Tibetan sheep PDGFB gene is 726 bp in length and encodes 241 amino acids with high homology to other mammals, particularly goats and antelopes. With the increase in age, PDGFB expression showed an overall trend of first decreasing and then increasing in the testis and epididymis tissues of Tibetan sheep, and the PDGFB mRNA expression at 3 months of age was extremely significantly higher than that at 1 and 3 years of age (p < 0.05). The PDGFB protein is mainly distributed in testicular red blood cells and Leydig cells in Tibetan sheep at all stages of development, as well as red blood cells in the blood vessel, principal cells, and the pseudostratified columnar ciliated epithelial cells of each epididymal duct epithelium. In addition, PDGFB protein expression was also detected in the spermatocytes of the 3-month-old group, spermatids of the 1-year-old group, spermatozoa and interstitial cells of the 3-year-old group, and loose connective tissue in the epididymal duct space in each developmental period. The above results suggest that the PDGFB gene, as an evolutionarily conserved gene, may play multiple roles in the development and functional maintenance of testicular cells (such as red blood cells, Leydig cells, and germ cells) and epididymal cells (such as red blood cells, principal cells, and ciliated epithelial cells) during testicular and epididymal development, which lays a foundation for the further exploration of the mechanisms by which the PDGFB gene influences spermatogenesis in Tibetan sheep.

3.
Nano Lett ; 24(18): 5444-5452, 2024 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-38639448

RESUMO

We report, for the first time, a new synthetic strategy for the preparation of crystalline two-dimensional olefin-linked covalent organic frameworks (COFs) based on aldol condensation between benzodifurandione and aromatic aldehydes. Olefin-linked COFs can be facilely crystallized through either a pyridine-promoted solvothermal process or a benzoic anhydride-mediated organic flux synthesis. The resultant COF leaf with high in-plane π-conjugation exhibits efficient visible-light-driven photoreduction of carbon dioxide (CO2) with water (H2O) in the absence of any photosensitizer, sacrificial agents, or cocatalysts. The production rate of carbon monoxide (CO) reaches as high as 158.1 µmol g-1 h-1 with near 100% CO selectivity, which is accompanied by the oxidation of H2O to oxygen. Both theoretical and experimental results confirm that the key lies in achieving exceptional photoinduced charge separation and low exciton binding. We anticipate that our findings will facilitate new possibilities for the development of semiconducting COFs with structural diversity and functional variability.

4.
Small ; 19(27): e2208118, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-36965021

RESUMO

The development of sp2 -carbon-linked covalent organic frameworks (sp2 c-COFs) as artificial photocatalysts for solar-driven conversion of CO2 into chemical feedstock has captured growing attention, but catalytic performance has been significantly limited by their intrinsic organic linkages. Here, a simple, yet efficient approach is reported to improve the CO2 photoreduction on metal-free sp2 c-COFs by rationally regulating their intrinsic π-conjugation. The incorporation of ethynyl groups into conjugated skeletons affords a significant improvement in π-conjugation and facilitates the photogenerated charge separation and transfer, thereby boosting the CO2 photoreduction in a solid-gas mode with only water vapor and CO2 . The resultant CO production rate reaches as high as 382.0 µmol g-1  h-1 , ranking at the top among all additive-free CO2 photoreduction catalysts. The simple modulation approach not only enables to achieve enhanced CO2 reduction performance but also simultaneously gives a rise to extend the understanding of structure-property relationship and offer new possibilities for the development of new π-conjugated COF-based artificial photocatalysts.

5.
Adv Sci (Weinh) ; 10(14): e2206807, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-36922735

RESUMO

Ultrasensitive flexible pressure sensors with excellent linearity are essential for achieving tactile perception. Although microstructured dielectrics have endowed capacitive sensors with ultrahigh sensitivity, the compromise of sensitivity with increasing pressure is an issue yet to be resolved. Herein, a spontaneously wrinkled MWCNT/PDMS dielectric layer is proposed to realize the excellent sensitivity and linearity of capacitive sensors for tactile perception. The synergistic effect of a high dielectric constant and wrinkled microstructures enables the sensor to exhibit linearity up to 21 kPa with a sensitivity of 1.448 kPa-1 and a detection limit of 0.2 Pa. Owing to these merits, the sensor monitors subtle physiological signals such as various arterial pulses and respiration. This sensor is further integrated into a fully multimaterial 3D-printed soft pneumatic finger to realize material hardness perception. Eight materials with different hardness values are successfully discriminated, and the capacitance of the sensor varies linearly (R2 > 0.975) with increasing hardness. Moreover, the sensitivity to the material hardness can be tuned by controlling the inflation pressure of the soft finger. As a proof of concept, the finger is used to discriminate pork fats with different hardness, paving the way for hardness discrimination in clinical palpation.

6.
Reprod Biol Endocrinol ; 20(1): 90, 2022 Jun 16.
Artigo em Inglês | MEDLINE | ID: mdl-35710416

RESUMO

BACKGROUND: Nonobstructive azoospermia (NOA) is one of the most difficult forms of male infertility to treat, and its pathogenesis is still unclear. miRNAs can regulate autophagy by affecting their target gene expression. Our previous study found that miR-188-3p expression in NOA patients was low. There are potential binding sites between the autophagy gene ATG7 and miR-188-3p. This study aimed to verify the binding site between miR-188-3p and ATG7 and whether miR-188-3p affects autophagy and participates in NOA by regulating ATG7 to influence the autophagy marker genes LC3 and Beclin-1. METHODS: Testicular tissue from 16 NOA patients and 16 patients with normal spermatogenesis and 5 cases in each group of pathological sections were collected. High-throughput sequencing was performed to detect mRNA expression differences. Quantitative real-time polymerase chain reaction (qRT-PCR), Western blotting, immunohistochemical staining and immunofluorescence were used to detect protein localization and expression. Autophagosome changes were detected by electron microscopy. The targeting relationship between miR-188-3p and ATG7 was confirmed by a luciferase assay. RESULTS: ATG7 protein was localized in the cytoplasm of spermatogenic cells at all levels, and the ATG7 gene (p = 0.019) and protein (p = 0.000) were more highly expressed in the NOA group. ATG7 expression after overexpression/inhibition of miR-188-3p was significantly lower (p = 0.029)/higher (p = 0.021) than in the control group. After overexpression of miR-188-3p, the ATG7 3'UTR-WT luciferase activity was impeded (p = 0.004), while the ATG7 3'UTR-MUT luciferase activity showed no significant difference (p = 0.46). LC3 (p = 0.023) and Beclin-1 (p = 0.041) expression in the NOA group was significantly higher. LC3 and Beclin-1 gene expression after miR-188-3p overexpression/inhibition was significantly lower (p = 0.010 and 0.024, respectively) and higher (p = 0.024 and 0.049, respectively). LC3 punctate aggregation in the cytoplasm decreased after overexpression of miR-188-3p, while the LC3 punctate aggregation in the miR-188-3p inhibitor group was higher. The number of autophagosomes in the miR-188-3p mimic group was lower than the number of autophagosomes in the mimic NC group. CONCLUSIONS: LC3 and Beclin-1 were more highly expressed in NOA testes and negatively correlated with the expression of miR-188-3p, suggesting that miR-188-3p may be involved in the process of autophagy in NOA. miR-188-3p may regulate its target gene ATG7 to participate in autophagy anDual luciferase experiment d affect the development of NOA.


Assuntos
Azoospermia , MicroRNAs , Regiões 3' não Traduzidas , Autofagia/genética , Proteína 7 Relacionada à Autofagia/genética , Azoospermia/genética , Proteína Beclina-1/genética , Humanos , Masculino , MicroRNAs/genética , MicroRNAs/metabolismo
7.
ACS Macro Lett ; 11(1): 60-65, 2022 Jan 18.
Artigo em Inglês | MEDLINE | ID: mdl-35574782

RESUMO

A dual rate-modulation approach was implemented for the first time to create crystalline covalent triazine frameworks. Based on a new polycondensation approach, regulating the condensation rate via the exploitation of a modulated aldehyde monomer and addition of an extrinsic inhibitor affords inherent control over the polymer growth and therefore provides tunable crystallinities and porosities for the resulting triazine frameworks. The existence of rich redox-active triazine linkages gives rise to obtaining exceptional sodium storage, where 239 mAh g-1 at 1.0 A g-1 is obtained after 200 cycles. We anticipate this new protocol based on the dynamic imine metathesis will facilitate new possibilities for the construction of crystalline covalent triazine frameworks and promote their energy-related applications.

8.
Chemosphere ; 294: 133735, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35085615

RESUMO

Single-atom Fe catalysts have shown great potential for Fenton-like technology in organic pollutant decomposition. However, the underlying reaction pathway and the identification of Fe active sites capable of activating peroxymonosulfate (PMS) across a wide pH range remain unknown. We presented a novel strategy for deciphering the production of singlet oxygen (1O2) by regulating the Fe active sites in this study. Fe single atoms loaded on nitrogen-doped porous carbon (FeSA-CN) catalysts were synthesized using a cage encapsulation method and compared to Fe-nanoparticle-loaded catalysts. It was discovered that FeSA-CN catalysts served as efficient PMS activators for pollutant decomposition over a wide pH range. Several analytical measurements and density functional theory calculations revealed that the pyridinic N-ligated Fe single atom (Fe-pyridine N4) was involved in the production of 1O2 by the binding of two PMS ions, resulting in an excellent catalytic performance for PMS adsorption/activation. This work has the potential to not only improve the understanding of nonradical reaction pathway but to also provide a generalizable method for producing highly stable PMS activators with high activity for practical wastewater treatment.


Assuntos
Ferro , Peróxidos , Antibacterianos , Concentração de Íons de Hidrogênio , Piridinas
9.
Fertil Steril ; 115(2): 463-473, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-33579525

RESUMO

OBJECTIVE: To investigate the expression of aquaporin 7 (AQP7) and aquaporin 9 (AQP9) in the granulosa cells of patients with polycystic ovary syndrome (PCOS) and healthy women and detect their localization in oocytes at the germinal vesicle (GV), metaphase I (MI), MII, embryo, and blastocyst stages and the in vitro response to insulin stimulation. DESIGN: Randomized, assessor-blinded study. SETTING: Reproductive medical center. PATIENT(S): A total of 40 women (aged 20-38 years) comprising 29 cases of primary infertility and 11 cases of secondary infertility, of whom 17 had an initial diagnosis of PCOS and three received a PCOS diagnosis after an infertility examination. INTERVENTION(S): Controlling different concentrations of insulin and different treatment times in cultures of normal human granulosa cells in vitro. MAIN OUTCOME MEASURE(S): Expression of AQP7 and AQP9 genes and proteins in granulosa cells detected by real-time quantitative polymerase chain reaction, and localization in oocytes at the GV, MI, MII, embryo, and blastocyst stages by Western blot, immunohistochemical, and immunofluorescence assays, and concentrations of insulin in follicular fluid by enzyme-linked immunosorbent assay. RESULT(S): The expression levels of the AQP7 mRNA and protein in the granulosa cells of patients with PCOS were higher than found in healthy controls. We found AQP7 protein expressed in human oocytes at GV, MI, MII, embryo, and blastocyst stages; it was mainly located in the nucleoplasm. In the PCOS group, the expression level of AQP9 mRNA and protein in granulosa cells was lower, and AQP9 protein was expressed in oocytes at the GV, MI, MII, embryo, and blastocyst stages; it was localized on the nuclear membrane. Compared with healthy women, the insulin expression in patients with PCOS was higher. In cultures of normal human granulosa cells in vitro, the expression of AQP7 and AQP9 mRNA and protein decreased with the increase in insulin concentration; expression statistically significantly decreased when the insulin concentration was 100 nmol/L, and after 6 to 24 hours of exposure the lowest expression levels were found at 12 hours. CONCLUSION(S): The different localization and expression of AQP7 and AQP9 between the two groups suggests that they might be involved in oocyte maturation and embryonic development through different regulatory pathways. The expression levels of AQP7 and AQP9 were negatively correlated with insulin regulation, suggesting that insulin might affect the maturation of PCOS follicles by changing AQP7 and AQP9 expression.


Assuntos
Aquaporinas/biossíntese , Regulação da Expressão Gênica no Desenvolvimento , Células da Granulosa/metabolismo , Insulina/metabolismo , Oócitos/metabolismo , Síndrome do Ovário Policístico/metabolismo , Adulto , Aquaporinas/genética , Feminino , Humanos , Infertilidade Feminina/epidemiologia , Infertilidade Feminina/genética , Infertilidade Feminina/metabolismo , Insulina/genética , Síndrome do Ovário Policístico/epidemiologia , Síndrome do Ovário Policístico/genética , Método Simples-Cego , Adulto Jovem
10.
Chembiochem ; 21(15): 2143-2148, 2020 08 03.
Artigo em Inglês | MEDLINE | ID: mdl-32189429

RESUMO

Penicillin G acylase (PGA) has been immobilized on a lanthanum-incorporated mesostructured cellular foam (La-MCF) support by using the interaction between the strong Lewis acid sites on the surface of La-MCF and the free amino groups of lysine residues of PGA. The La-MCF support was successfully synthesized in situ through the addition of a citric acid (CA) complexant. The results of pyridine-IR spectroscopy show the presence of strong Lewis acid sites on the surface of the prepared La-MCF (with CA), attributed to the incorporation of lanthanum species into the framework of MCF. Through interaction with the strong Lewis acid sites, the enzymes can be firmly immobilized on the surface of the support. The results indicate that PGA/La-MCF (with CA) exhibits a high specific activity and greatly enhanced operational stability. For the hydrolysis of penicillin G potassium salt, the initial specific activity of PGA/La-MCF (with CA) reaches 10023 U/g. Even after being recycled 10 times, PGA/La-MCF (with CA) retains 89 % of its initial specific activity, much higher than the 77 % of PGA/Si-MCF.


Assuntos
Enzimas Imobilizadas/química , Enzimas Imobilizadas/metabolismo , Lantânio/química , Penicilina Amidase/química , Penicilina Amidase/metabolismo , Dióxido de Silício/química , Ácidos de Lewis/química , Bases de Lewis/química , Porosidade
11.
Sci Rep ; 10(1): 2929, 2020 Feb 19.
Artigo em Inglês | MEDLINE | ID: mdl-32076057

RESUMO

Industrial flue gas systems include fine soot and high-temperature vapor. The continuous emission of the flue gas not only causes fine particulate pollution but also wastes considerable heat energy. Separating soot and purifying flue gas are of great significance for industrial conditions and environmental protection. In this paper, the process of cyclone soot elimination and waste heat recovery by heterogeneous condensation were coupled for the first time. The effects of the flue gas material system and separation operation parameters on the cyclone soot elimination efficiency and heat transfer efficiency were systematically investigated through unit experiments and industrial side-lines. Additionally, the mechanism of enhanced cyclone soot elimination by heterogeneous condensation was also theoretically explored. The experimental results show that the corresponding maximum cyclone heat transfer efficiency and soot elimination efficiency of the Ф40 mm cyclone separator are 42.1% and 89.2%, respectively, while the Ф80 mm cyclone separator can attain an elimination efficiency of 91% and a maximum increase of 67.3% for the heat transfer efficiency, as indicated by the industrial side-line. During the process of cyclone soot elimination and heat recovery by heterogeneous condensation, the heterogeneous condensation caused by heat transfer increases the quality difference between the flue gas molecules and soot droplets, thus improving the cyclone separation efficiency of soot.

12.
Chem Sci ; 10(9): 2585-2591, 2019 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-30996973

RESUMO

Single-atom catalysts (SACs) have shown great potential in a wide variety of chemical reactions and become the most active new frontier in catalysis due to the maximum efficiency of metal atom use. The key obstacle in preparing SAs lies in the development of appropriate supports that can avoid aggregation or sintering during synthetic procedures. As such, achieving high loadings of isolated SAs is nontrivial and challenging. Conventional methods usually afford the formation of SAs with extremely low loadings (less than 1.5 wt%). In this work, a new in situ preparation strategy that enables the synthesis of isolated cobalt (Co) SAs with an exceptionally high metal loading, up to 5.9 wt%, is developed. The approach is based on a simple one-step pyrolysis of a nitrogen-enriched molecular carbon precursor (1,4,5,8,9,12-hexaazatriphenylene hexacarbonitrile) and CoCl2. Furthermore, due to the successful electron transfer from carbon nitride to the isolated Co SAs, we demonstrate a high-performance photocatalytic H2 production using Co SAs as a co-catalyst, and the evolution rate is measured to be 1180 µmol g-1 h-1. We anticipate that this new study will inspire the discovery of more isolated SACs with high metal loadings, evidently advancing the development of this emerging type of advanced catalysts.

13.
ACS Appl Mater Interfaces ; 10(50): 43588-43594, 2018 Dec 19.
Artigo em Inglês | MEDLINE | ID: mdl-30482016

RESUMO

The first study of rational synthesis of triazine-based nanoporous frameworks as electrocatalysts for CO2 reduction reaction (CO2RR) was presented. The resulting optimized framework with rich pyridinic nitrogen-containing sites can selectively reduce CO2 to CO in water with a high Faradic efficiency of ca. 82% under a moderate overpotential of 560 mV. The key of our success lies in the use of pyridine-based backbones as sacrificial groups inside the triazine framework for in situ generation of CO2RR-active pyridinic N-doped sites during the high-temperature ZnCl2-promoted polymerization process. We anticipate that this study may facilitate new possibilities for the development of porous organic polymers for electrochemical conversion of CO2.

14.
Chem Commun (Camb) ; 54(40): 5058-5061, 2018 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-29726871

RESUMO

A simple charge modulation approach has been developed to stabilize naked Au clusters on a nanoporous conjugated organic network. Through engineering pore walls with regulated charges, the controllable growth of Au nanoclusters has been realized. The resulting supported catalyst exhibits excellent performance in the aerobic oxidation of alcohols.

15.
J Hazard Mater ; 342: 290-296, 2018 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-28843798

RESUMO

A novel heterostructured material, cobalt phosphate-SiO2 mesostructured cellular foams (CoPO-MCF), was successfully synthesized by in situ growth. The material was characterized by X-ray diffraction (XRD), nitrogen sorption, temperature-programmed reduction (H2-TPR and CO-TPR), temperature-programmed desorption of NH3 (NH3-TPD), and X-ray photoelectron spectroscopy (XPS). A ruthenium precursor was readily introduced and highly dispersed on the CoPO nanophases of the CoPO-MCF through an impregnation method. The resulting Ru/CoPO-MCF catalyst exhibited high catalytic activity for the oxidation of vinyl chloride (VC). The results of three consecutive runs and long-term tests showed high stability of the Ru/CoPO-MCF for the catalytic oxidation of VC. The unique heterostructures of the CoPO-MCF not only improve the reducibility and acidity of the MCF but also strengthen the interaction between ruthenium oxide nanoparticles and the CoPO-MCF support, which contributes to the enhanced catalytic performance.

16.
Angew Chem Int Ed Engl ; 57(11): 2816-2821, 2018 03 05.
Artigo em Inglês | MEDLINE | ID: mdl-29285842

RESUMO

Achieving homogeneous dispersion of nanoporous fillers within membrane architectures remains a great challenge for mixed-matrix membrane (MMMs) technology. Imparting solution processability of nanoporous materials would help advance the development of MMMs for membrane-based gas separations. A mechanochemically assisted oxidative coupling polymerization strategy was used to create a new family of soluble nanoporous polymer networks. The solid-state ball-milling method affords inherent molecular weight control over polymer growth and therefore provides unexpected solubility for the resulting nanoporous frameworks. MMM-based CO2 /CH4 separation performance was significantly accelerated by these new soluble fillers. We anticipate this facile method will facilitate new possibilities for the rational design and synthesis of soluble nanoporous polymer networks and promote their applications in membrane-based gas separations.

17.
Adv Mater ; 29(47)2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-29068542

RESUMO

An in situ coupling approach is developed to create a new highly efficient and durable cobalt-based electrocatalyst for the oxygen evolution reaction (OER). Using a novel cyclotetramerization, a task-specific bimetallic phthalocyanine-based nanoporous organic framework is successfully built as a precursor for the carbonization synthesis of a nonprecious OER electrocatalyst. The resultant material exhibits an excellent OER activity with a low overpotential of 280 mV at a current density of 10 mA cm-2 and high durability in an alkaline medium. This impressive result ranks among the best from known Co-based OER catalysts under the same conditions. The simultaneous installation of multiple diverse cobalt-based active sites, including FeCo alloys and Co4 N nanoparticles, plays a critical role in achieving this promising OER performance. This innovative approach not only enables high-performance OER activity to be achieved but simultaneously provides a means to control the surface features, thereby tuning the catalytic property of the material.

18.
ChemSusChem ; 10(17): 3304-3316, 2017 09 11.
Artigo em Inglês | MEDLINE | ID: mdl-28796390

RESUMO

Membrane-based CO2 separation technology plays a significant role in environmental remediation and clean energy. Two-dimensional (2D) materials with atomically precise structures have emerged as prospective scaffolds to develop mixed-matrix membranes (MMMs) for gas separation. Summarized in this perspective review are the latest breakthrough studies in the synthesis of 2D-material-based MMMs to separate CO2 from gas mixtures. 2D materials including graphene oxide (GO), metal-organic framework (MOF)-derived nanosheets, covalent organic frameworks (COFs), and transition metal dichalcogenides (TMDs), as fascinating building blocks, have been comprehensively summarized, together with a focus on synthetic processes and gas separation properties. Challenges and the latest advances in the manufacture of novel synthetic 2D materials are briefly discussed to foresee emerging opportunities for the development of new generations of 2D-material-based MMMs.


Assuntos
Dióxido de Carbono/isolamento & purificação , Fracionamento Químico/métodos , Membranas Artificiais , Dióxido de Carbono/química , Grafite/química , Nanoestruturas/química , Compostos Organometálicos/química
19.
Chem Commun (Camb) ; 53(54): 7645-7648, 2017 Jul 04.
Artigo em Inglês | MEDLINE | ID: mdl-28642957

RESUMO

A superacid-promoted "knitting" strategy has been developed for the generation of a novel family of hypercrosslinked nanoporous polycarbazoles for efficient CO2 capture. Using trifluoromethanesulfonic acid, a Brønsted superacid, we demonstrate the facile and rapid synthesis of highly porous polycarbazoles with BET surface areas as high as 1688 m2 g-1, and capable of adsorbing 3.5 mmol g-1 of CO2 at 298 K and 1 bar. This impressive result bestows the material with the highest CO2 uptake capacity for all nanoporous carbazolic polymers and ranks among the best by known porous organic polymers under this condition. This innovative approach affords a metal-free alternative to Friedel-Crafts alkylation, and may open up new possibilities for the rational design and synthesis of new hypercrosslinked nanoporous organic networks for carbon capture.

20.
ChemSusChem ; 10(11): 2348-2351, 2017 06 09.
Artigo em Inglês | MEDLINE | ID: mdl-28333410

RESUMO

Transition-metal-catalyzed cyanation of aryl halides is a common route to benzonitriles, which are integral to many industrial procedures. However, traditional homogeneous catalysts for such processes are expensive and suffer poor recyclability, so a heterogeneous analogue is highly desired. A novel spatial modulation approach has been developed to fabricate a heterogeneous Pd-metalated nanoporous polymer, which catalyzes the cyanation of aryl halides without need for ligands. The catalyst displays high activity in the synthesis of benzonitriles, including high product yields, excellent stability and recycling, and broad functional-group tolerance.


Assuntos
Nitrilas/síntese química , Paládio/química , Derivados de Benzeno/química , Carbazóis/química , Catálise , Cianetos/química , Halogênios , Nanoporos , Nitrilas/economia , Polímeros , Reciclagem
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