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1.
Environ Monit Assess ; 196(7): 605, 2024 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-38856803

RESUMO

Petroleum hydrocarbons (PHCs) are produced from industrial discharges, storage leakages, accidental spills, and operational failures. The hazardous nature of PHCs causes serious health risks and threatens the entire aquatic habitat. In this research work, the investigation of the removal of total petroleum hydrocarbons (TPHs) from the contaminated water is carried out utilizing a novel hypercross-linked resin, MAICY, which is generated by condensation of commercially available precursors. The chemical structures of MAICY have been examined extensively by FESEM, FT-IR, solid (CP-MAS) 13C-NMR, and TGA. A comprehensive analysis for adsorption parameters of TPHs has been performed, and different models such as Langmuir and Freundlich isotherms have been employed where the Freundlich isotherm was found to be the best fit for removal of THPs (R2= 0.9991). The results revealed that the performance of MAICY for the adsorption of TPHs from contaminated water gives a maximum adsorption capacity (qe) of 146 mg.g-1. The results of various parameters hinted that the contact time (0.25-4 h), the dosage of adsorbent (0.17 g/L), pH (7), and concentration of TPHs (26.5 mg/L) have controlled the overall adsorptive performance. Moreover, the kinetic data of qe(expt.) and qe(calc.) for adsorption of TPHs disclosed the regression values (R2) for pseudo-first order (R2= 0.9921) and pseudo-second order (R2= 0.9891). Additionally, based on CHI factor (X2) error estimations, the data was shown to be more consistent with pseudo-first-order kinetics. Moreover, MAICY demonstrated excellent reusability and recycling properties for up to four consecutive adsorption-desorption cycles.


Assuntos
Hidrocarbonetos , Petróleo , Triazinas , Poluentes Químicos da Água , Poluentes Químicos da Água/análise , Adsorção , Petróleo/análise , Triazinas/química , Triazinas/análise , Cinética
2.
Future Med Chem ; 15(18): 1651-1668, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37727987

RESUMO

Background: Diabetes mellitus (DM) is a chronic disorder, considered to be a major global health challenge in the 21st century. α-Glucosidase enzyme is a well-known drug target to treat Type II DM. Methods: A new library of biphenyl-substituted triazines was synthesized and confirmed by various spectroscopic techniques. Results: All compounds showed potent α-glucosidase inhibitory activity, with IC50 values ranging from 35.35 ± 0.34 to 564.41 ± 0.91 µM, as the standard acarbose, IC50 value of 750.7 ± 0.13 µM. Our in silico study has predicted key interactions with the enzyme's active site. Drug-likeness and absorption, distribution, metabolism, excretion and toxicity were also studied. Conclusion: This study has identified a range of potential hits against the α-glucosidase enzyme that may serve as antidiabetic agents after further investigations.


Assuntos
Inibidores de Glicosídeo Hidrolases , alfa-Glucosidases , Inibidores de Glicosídeo Hidrolases/química , alfa-Glucosidases/metabolismo , Hipoglicemiantes/química , Cinética , Triazinas/farmacologia , Triazinas/química , Simulação de Acoplamento Molecular , Relação Estrutura-Atividade , Estrutura Molecular
3.
Adv Mater ; 35(47): e2301342, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37548517

RESUMO

The uncondensed form of polymeric carbon nitrides (PCN), generally known as melon, is a stacked 2D structure of poly(aminoimino)heptazine. Melon is used as a photocatalyst in solar energy conversion applications, but suffers from poor photoconversion efficiency due to weak optical absorption in the visible spectrum, high activation energy, and inefficient separation of photoexcited charge carriers. Experimental and theoretical studies are reported to engineer the bandgap of melon with highly reduced graphene oxide (HRG). Three HRG@melon nanocomposites with different HRG:melon ratios (0.5%, 1%, and 2%) are prepared. The 1% HRG@melon nanocomposite shows higher photocurrent density (71 µA cm-2 ) than melon (24 µA cm-2 ) in alkaline conditions. The addition of a hole scavenger further increases the photocurrent density to 630 µA cm-2 relative to the reversible hydrogen electrode (RHE). These experimental results are validated by calculations using density functional theory (DFT), which revealed that HRG results in a significant charge redistribution and an improved photocatalytic hydrogen evolution reaction (HER).

4.
Int J Biol Macromol ; 241: 124589, 2023 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-37116840

RESUMO

A library of 2-oxopyridine carbonitriles 1-34 was synthesized by regioselective nucleophilic substitution reactions. In the first step, a one-pot multicomponent reaction yield pyridone intermediates. The resulting pyridone intermediates were then reacted with phenacyl halides in DMF and stirred at 100 °C for an hour to afford the desired compounds in good yields. Structures of synthetic molecules were characterized by EI-MS, HREI-MS, 1H NMR, and 13C NMR, and all thirty-four (34) compounds were found to be new. All synthetic compounds were examined for antidiabetic and antioxidant potential. The compounds exhibited α-glucosidase inhibitory potential in the range of IC50 = 3.00 ± 0.11-43.35 ± 0.67 µM and α-amylase inhibition potential in the range of IC50 = 9.20 ± 0.14-65.56 ± 1.05 µM. Among the tested compounds, 1 showed the most significant α-glucosidase inhibitory activity, with an IC50 value of 3.00 ± 0.11 µM, while the most active compound against α-amylase was 6, with an IC50 value = 9.20 ± 0.14 µM. The kinetic studies and analysis indicated that the compounds followed the competitive mode of inhibition. In addition, the molecular docking studies showed the interaction profile of all molecules with the binding site residues of α-glucosidase and α-amylase enzymes.


Assuntos
Antioxidantes , Hipoglicemiantes , Hipoglicemiantes/farmacologia , Hipoglicemiantes/química , Antioxidantes/farmacologia , Antioxidantes/química , Relação Estrutura-Atividade , Simulação de Acoplamento Molecular , alfa-Glucosidases/metabolismo , Cinética , alfa-Amilases/química , Piridonas , Inibidores de Glicosídeo Hidrolases/farmacologia , Inibidores de Glicosídeo Hidrolases/química , Estrutura Molecular
5.
Chem Rev ; 123(8): 4443-4509, 2023 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-37067292

RESUMO

Energy from renewable resources is central to environmental sustainability. Among the renewables, sunlight-driven fuel synthesis is a sustainable and economical approach to produce vectors such as hydrogen through water splitting. The photocatalytic water splitting is limited by the water oxidation half-reaction, which is kinetically and energetically demanding and entails designer photocatalysts. Such challenges can be addressed by employing alternative oxidation half-reactions. Photoreforming can drive the breakdown of waste plastics and biomass into valuable organic products for the production of H2. We provide an overview of photoreforming and its underlying mechanisms that convert waste polymers into H2 fuels and fine chemicals. This is of paramount importance from two complementary perspectives: (i) green energy harvesting and (ii) environmental sustainability by decomposing waste polymers into valuables. Competitive results for the generation of H2 fuel without environmental hazards through photoreforming are being generated. The photoreforming process, mechanisms, and critical assessment of the field are scarce. We address such points by focusing on (i) the concept of photoreforming and up-to-date knowledge with key milestones achieved, (ii) uncovering the concepts and challenges in photoreforming, and (iii) the design of photocatalysts with underlying mechanisms and pathways through the use of different polymer wastes as substrates.

6.
Arch Pharm (Weinheim) ; 356(1): e2200400, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36284484

RESUMO

Herein, a library of novel pyridone derivatives 1-34 was designed, synthesized, and evaluated for α-amylase and α-glucosidase inhibitory as well as antioxidant activities. Pyridone derivatives 1-34 were synthesized via a one-pot multi-component reaction of variously substituted aromatic aldehydes, acetophenone, ethyl cyanoacetate, and ammonium acetate in absolute ethanol. Synthetic compounds 1-34 were structurally characterized by different spectroscopic techniques. Most of the tested compounds showed more promising inhibition potential than the standard acarbose (IC50 = 14.87 ± 0.16 µM) but compounds 13 and 12 were found to be the most potent compounds with IC50 values of 9.20 ± 0.14 µM and 3.05 ± 0.18 µM against α-amylase and α-glucosidase enzymes, respectively. Compounds 1-34 also displayed moderate antioxidant potential in the range of IC50 = 96.50 ± 0.45 to 189.98 ± 1.00 µM in comparison to the control butylated hydroxytoluene (BHT) (IC50 = 66.50 ± 0.36 µM), in DPPH radical scavenging activities. Additionally, all synthetic derivatives were subjected to a molecular docking study to investigate the interaction details of compounds 1-34 (ligands) with the active site of enzymes (receptors). These results indicate that the newly synthesized pyridone class may serve as promising lead candidates for controlling diabetes mellitus and as antioxidants.


Assuntos
Antioxidantes , alfa-Glucosidases , Antioxidantes/farmacologia , Antioxidantes/química , alfa-Glucosidases/metabolismo , Relação Estrutura-Atividade , Simulação de Acoplamento Molecular , alfa-Amilases , Inibidores de Glicosídeo Hidrolases/farmacologia , Inibidores de Glicosídeo Hidrolases/química
7.
ACS Omega ; 7(44): 39822-39829, 2022 Nov 08.
Artigo em Inglês | MEDLINE | ID: mdl-36385827

RESUMO

Viscoelastic surfactants (VESs) have significant importance for stimulation of low-permeable reservoirs and acid diversion applications to effectively enhance hydrocarbon productivity. VESs offer lower residues, complete gel production, and lower formation damage that make them suitable candidates for hydraulic fracturing applications. In this research work, the synthesis of two new zwitterionic gemini surfactants 1 and 2 together with previously known amidosulfobutaine (C18AMP3SB) has been achieved. Evaluation of viscosity behavior of neat surfactants in CaCl2 solutions at varied temperatures and shear rates did not show any upsurge in their viscosities. Nevertheless, a mixture of surfactants 1 and 2 in combination with C18AMP3SB displayed a significant increase in viscosity, transforming the solution into a highly viscous gel. At a fixed shear rate of 35 s-1 and under different temperatures, solutions of the mixture of surfactants 1 and C18AMP3SB displayed viscosities ranging from 4.34 to 354.3 cPs (81-fold enhancement). Likewise, viscosities of formulations based on mixing 2 and C18AMP3SB under identical experimental conditions ranged from 3.89 to 290 cPs (74-fold enhancement). The viscofying stability tests at 90 °C at a shear rate of 35 s-1 of mixed surfactant formulations revealed no appreciable change in their viscosities for up to 1 h. Moreover, temperature-dependent experiments suggested an increase in the viscosity with an increase in temperature. Thermogravimetric analysis revealed that these surfactants are thermally stable, with no appreciable loss of mass up to 300 °C. The viscoelastic properties of these surfactants suggest their potential and utility in well stimulation for enhanced oil recovery.

8.
ACS Omega ; 7(40): 35446-35485, 2022 Oct 11.
Artigo em Inglês | MEDLINE | ID: mdl-36249392

RESUMO

Functionalized chiral indole derivatives are privileged and versatile organic frameworks encountered in numerous pharmaceutically active agents and biologically active natural products. The catalytic asymmetric Friedel-Crafts reaction of indoles, catalyzed by chiral metal complexes or chiral organocatalysts, is one of the most powerful and atom-economical approaches to access optically active indole derivatives. Consequently, a wide range of electrophilic partners including α,ß-unsaturated ketones, esters, amides, imines, ß,γ-unsaturated α-keto- and α-ketiminoesters, ketimines, nitroalkenes, and many others have been successfully employed to achieve a plethora of functionalized chiral indole moieties. In particular, strategies for C-H functionalization in the phenyl of indoles require incorporation of a directing or blocking group in the phenyl or azole ring of indole. The discovery of chiral catalysts which can control enantiodiscrimination has gained a great deal of attention in recent years. This review will provide an updated account on the application of the asymmetric Friedel-Crafts reaction of indoles in the synthesis of diverse chiral indole derivatives, covering the timeframe from 2011 to today.

9.
Angew Chem Int Ed Engl ; 61(47): e202209494, 2022 11 21.
Artigo em Inglês | MEDLINE | ID: mdl-36200408

RESUMO

A sequential phosphine-catalyzed asymmetric [3+2] annulation of aldimines with allenoates and oxidative central-to-axial chirality transfer strategy has been developed. This approach is operationally simple, allowing for rapid access to a range of axially chiral CF3 -containing 2-arylpyrroles with high enantiomeric excess. Furthermore, an atroposelective synthesis of esaxerenone is presented, illustrating the practical potential of the reported method.


Assuntos
Fosfinas , Catálise , Estereoisomerismo , Estresse Oxidativo
10.
Arab J Chem ; 15(12): 104366, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36276298

RESUMO

We report microwave synthesis of seven unique pyrimidine anchored derivatives (1-7) incorporating multifunctional amino derivatives along with their in vitro anticancer activity and their activity against COVID-19 in silico. 1-7 were characterized by different analytical and spectroscopic techniques. Cytotoxic activity of 1-7 was tested against HCT116 and MCF7 cell lines, whereby 6 exhibited highest anticancer activity on HCT116 and MCF7 with EC50 values of 89.24 ± 1.36 µM and 89.37 ± 1.17 µM, respectively. Molecular docking was performed for derivatives (1-7) on main protease for SARS-CoV-2 (PDB ID: 6LU7). Results revealed that most of the derivatives had superior or equivalent affinity for the 3CLpro, as determined by docking and binding energy scores. 6 topped the rest with highest binding energy score of -8.12 kcal/mol with inhibition constant reported as 1.11 µM. ADME, drug-likeness, and pharmacokinetics properties of 1-7 were tested using Swiss ADME tool. Toxicity analysis was done with pkCSM online server. All derivatives showed high GI absorption. Except 1 and 3, all derivatives showed blood brain barrier permeability. Most derivatives showed negative logKp values suggesting derivatives are less skin permeable and bioavailability score of all derivatives was 0.55. The toxicity analysis demonstrated that all derivatives have no skin sensitization properties. 6 and 7 showed maximum tolerated dose (Human) values of -0.03 and -0.018, respectively and absence of AMES toxicity.

11.
Mikrochim Acta ; 189(11): 426, 2022 10 19.
Artigo em Inglês | MEDLINE | ID: mdl-36260130

RESUMO

Monitoring of pollutant and toxic substances is essential for cleaner environment and healthy life. Sensing of various environmental contaminants and biomolecules such as heavy metals, pharmaceutics, toxic gases, volatile organic compounds, food toxins, and pathogens is of high importance to guaranty the good health and sustainable environment to community. In recent years, graphitic carbon nitride (g-CN) has drawn a significant amount of interest as a sensor due to its large surface area and unique electrochemical properties, low bandgap energy, high thermal and chemical stability, facile synthesis, nontoxicity, and electron rich property. Furthermore, the binary and ternary nanocomposites of graphitic carbon nitride further enhance their performance as a sensor making it a cost effective, fast, and reliable gadget for the purpose, and opens a wide area of research. Numerous reviews addressing a variety of applications including photocatalytic energy conversion, photoelectrochemical detection, and hydrogen evolution of graphitic carbon nitride have been documented to date. But a lesser attention has been devoted to the mechanistic approaches towards sensing of variety of pollutants concerned with environmental and biological aspects. Herein, we present the sensing features of graphitic carbon nitride towards the detection of various analytes including toxic heavy metals, pharmaceuticals, phenolic compounds, nitroaromatic compounds, volatile organic molecules, toxic gases, and foodborne pathogens. This review will undoubtedly provide future insights for researchers working in the field of sensors, allowing them to investigate the intriguing graphitic carbon nitride material as a sensing platform that is comparable to several other nanomaterials documented in the literature. Therefore, we hope that this study could reveal some intriguing sensing properties of graphitic carbon nitride, which may help researchers better understand how it interacts with contaminants of environmental and biological concern. Graphitic carbon nitride Nanosheets as Promising Analytical Tool for Environmental and Biological Monitoring of Hazardous Substances.


Assuntos
Poluentes Ambientais , Nanocompostos , Compostos Orgânicos Voláteis , Nanocompostos/química , Gases , Substâncias Perigosas , Hidrogênio , Preparações Farmacêuticas
12.
Chem Rec ; 22(8): e202200062, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35641392

RESUMO

Covalent organic frameworks (COFs) are a promising class of porous crystalline materials made up of covalently connected and periodically protracted network topologies through organic linkers. The tailorability of organic linker and intrinsic structures endow COFs with a tunable porosity and structure, low density, facilely-tailored functionality, and large surface area, attracting increasing amount of interests in variety of research areas of membrane separations. COF-based membranes have spawned a slew of new research projects, ranging from fabrication methodologies to separation applications. Herein, we tried to emphasis the major developments in the synthetic approaches of COFs based membranes for a variety of separation applications such as, separation of gaseous mixtures, water treatment as well as separation of isomeric and chiral organic compounds. The proposed methods for fabricating COF-based continuous membranes and columns for real world applications are also thoroughly explored. Finally, a viewpoint on the future directions and remaining challenges for COF research in the area of separation is provided.


Assuntos
Estruturas Metalorgânicas , Purificação da Água , Gases , Estruturas Metalorgânicas/química , Compostos Orgânicos , Porosidade
13.
Spectrochim Acta A Mol Biomol Spectrosc ; 278: 121381, 2022 Oct 05.
Artigo em Inglês | MEDLINE | ID: mdl-35588604

RESUMO

The localized surface plasmon resonance (LSPR) excitations are critical towards achieving sizable spectral enhancements of the Raman scattered light. Herein, the synthesis of palladium-based highly reduced graphene oxide (Pd-HRG) with LSPR properties as an effective surface-enhanced Raman scattering (SERS) substrate and its utility in the highly sensitive detection of procaine are reported. The concentration detection of procaine samples was optimized by applying a set of pre-concentration parameters. The Pd-HRG nanocomposite showed a remarkable LSPR response with a Raman enhancement factor of 8.7 × 102. The Pd-HRG is employed to modify fluorine doped tin oxide electrode (Pd-HRG/FTO), resulted with an enhancement factor of 7.5 × 104 corresponding to the EC-SERS technique. The electronic and surface properties of synthesized Pd-HRG and functionalized FTO electrode were evaluated using Raman, infrared, EIS, XRD, FESEM and EDX techniques. Quantum chemical calculations were carried out to elaborate on the nature of interaction of procaine molecules with a nanostructured surface model. Pd-HRG, with an efficient and cost-effective fabrication, can be considered as a promising EC-SERS substrate for the detection of organic therapeutic drugs.


Assuntos
Grafite , Nanocompostos , Anestésicos Locais , Grafite/química , Nanocompostos/química , Procaína , Análise Espectral Raman/métodos
14.
Chem Rec ; 22(7): e202100336, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35257485

RESUMO

The future challenges associated with the shortage of fossil fuels and their current environmental impacts intrigued the researchers to look for alternative ways of generating green energy. Solar-driven water splitting into oxygen and hydrogen is one of those advanced strategies. Researchers have studied various semiconductor materials to achieve potential results. However, it encountered multiple challenges such as high cost, low photostability and efficiency, and required multistep modifications. The conjugated polymers (CPs) have emerged as promising alternatives for conventional inorganic semiconductors. The CPs offer low cost, sufficient light absorption efficiency, excellent photo and chemical stability, and molecular optoelectronic tunable characteristics. Furthermore, organic CPs also present higher flexibility to tune the basic framework of the backbone of the polymers, amendments in the sidechain to incorporate desired functionalities, and much-needed porosity to serve better for photocatalytic applications. This review article summarizes the recent advancements made in visible-light-driven water splitting covering the aspects of synthetic strategies and experimental parameters employed for water splitting reactions with special emphasis on conjugated polymers such as linear CPs, planarized CPs, graphitic carbon nitride (g-C3 N4 ), conjugated microporous polymers (CMPs), covalent organic frameworks (COFs), and conjugated polymer-based nanocomposites (CPNCs). The current challenges and future prospects have also been described briefly.

15.
J Biomol Struct Dyn ; 40(21): 10730-10740, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-34463216

RESUMO

Herein, we report the synthesis and inhibitory potential of indazole (Methyl 1H-indazole-4-carboxylate) derivatives (1-13) against α-amylase and α-glucosidase enzymes. The described derivatives demonstrated good inhibitory potential with IC50 values, ranging between 15.04 ± 0.05 to 76.70 ± 0.06 µM ± SEM for α-amylase and 16.99 ± 0.19 to 77.97 ± 0.19 µM ± SEM for α-glucosidase, respectively. In particular, compounds (8-10 and 12) displayed significant inhibitory activities against both the screened enzymes, with their inhibitory potential comparable to the standard acarbose (12.98 ± 0.03 and 12.79 ± 0.17 µM ± SEM, respectively). Additionally, the influence of different substituents on enzyme inhibition activities was assessed to study the structure activity relationships. Molecular docking simulations were performed to rationalize the binding of derivatives/compounds with enzymes. All the synthesized derivatives (1-13) were characterized with the aid of spectroscopic instruments such as 1H-NMR, 13C-NMR, HR-MS, elemental analysis and FTIR.Communicated by Ramaswamy H. Sarma.


Assuntos
alfa-Amilases , alfa-Glucosidases , alfa-Glucosidases/química , alfa-Amilases/metabolismo , Simulação de Acoplamento Molecular , Inibidores de Glicosídeo Hidrolases/farmacologia , Inibidores de Glicosídeo Hidrolases/química , Indazóis/farmacologia , Relação Estrutura-Atividade , Estrutura Molecular
16.
Chem Soc Rev ; 50(17): 9766-9793, 2021 Sep 07.
Artigo em Inglês | MEDLINE | ID: mdl-34286704

RESUMO

The past two decades have witnessed remarkable growth of asymmetric organocatalysis, which is now a firmly established synthetic tool, serving as a powerful platform for the production of chiral molecules. Ring structures are ubiquitous in organic compounds, and, in the context of natural product synthesis, strategic construction of ring motifs is often crucial, fundamentally impacting the eventual fate of the whole synthetic plan. In this review, we provide a comprehensive and updated summary of asymmetric organocatalytic annulation reactions; in particular, the application of these annulation strategies in natural product synthesis will be highlighted.


Assuntos
Produtos Biológicos , Catálise , Compostos Orgânicos , Estereoisomerismo
17.
Acta Crystallogr E Crystallogr Commun ; 77(Pt 4): 372-377, 2021 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-33936760

RESUMO

The title compounds, 8-{1-[3-(cyclo-pent-1-en-1-yl)benz-yl]piperidin-4-yl}-2-meth-oxy-quinoline, C27H30N2O (I), and 8-{4-[3-(cyclo-pent-1-en-1-yl)benz-yl]piperazin-1-yl}-2-meth-oxy-quinoline, C26H29N3O (II), differ only in the nature of the central six-membered ring: piperidine in I and piperazine in II. They are isoelectronic (CH cf. N) and isotypic; they both crystallize in the triclinic space group P with very similar unit-cell parameters. Both mol-ecules have a curved shape and very similar conformations. In the biaryl group, the phenyl ring is inclined to the cyclo-pentene mean plane (r.m.s. deviations = 0.089 Šfor I and 0.082 Šfor II) by 15.83 (9) and 13.82 (6)° in I and II, respectively, and by 67.68 (6) and 69.47 (10)°, respectively, to the mean plane of the quinoline moiety (r.m.s. deviations = 0.034 Šfor I and 0.038 Šfor II). The piperazine ring in I and the piperidine ring in II have chair conformations. In the crystals of both compounds, mol-ecules are linked by C-H⋯π inter-actions, forming chains in I and ribbons in II, both propagating along the b-axis direction. The principal contributions to the overall Hirshfeld surfaces involve H⋯H contacts at 67.5 and 65.9% for I and II, respectively. The major contribution to the inter-molecular inter-actions in the crystals is from dispersion forces (E dis), reflecting the absence of classical hydrogen bonds.

18.
J Environ Manage ; 287: 112360, 2021 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-33752053

RESUMO

Water quality plays a central role in the well-being of all the living organisms on planet Earth. The ever-increasing human population and consequently increasing industrialization, urbanization, and chemically boosted cultivation are rapidly contaminating already stressed water resources. The availability of clean drinking water has become scarce for masses across the globe, and this situation is becoming alarming in developing countries. Therefore, the immediate need for cost-effective, easily accessible, eco-friendly, portable, thermally efficient, and chemically stable technologies and materials is desperately felt to meet the high global demand for clean water. To search for effective materials for wastewater treatment, the hyper-cross-linked porous polymers (HCPs) have emerged as an excellent class of porous materials for wastewater treatment due to their unique features of high surface area, tunability, biodegradability, and chemical versatility. This review describes the advances in fabrication strategies and the efficient utilization of hyper-cross-linked porous polymers for wastewater treatment. Moreover, this review specifically discusses the hyper-cross-linked porous polymers effectiveness for the separation of the dyes, nutrients, inorganic ions, organic contaminants, and toxic metals ions. Finally, the review provides insight into the challenges and prospects in the area of hyper-cross-linked porous polymers. Overall, the hyper-cross-linked porous polymers with empowering proper functionalization can provide an opportunity for the wastewater treatment not only to remove toxic contaminants but also to make contaminated water useful for various applications.


Assuntos
Poluentes Ambientais , Poluentes Químicos da Água , Adsorção , Corantes , Humanos , Íons , Polímeros , Porosidade , Águas Residuárias
19.
Acta Crystallogr E Crystallogr Commun ; 77(Pt 2): 208-212, 2021 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-33614156

RESUMO

The amine 8-{4-[(6-phenyl-pyridin-3-yl)meth-yl]piperazin-1-yl}-3,4-di-hydro-quinolin-2(1H)-one was crystallized as the hydro-chloride salt, 4-(2-oxo-1,2,3,4-tetra-hydro-quinolin-8-yl)-1-[(6-phenyl-pyridin-3-yl)meth-yl]piperazin-1-ium chloride, C25H27N4 +·Cl- (I·HCl). The conformation of the organic cation is half-moon in shape enclosing the chloride anion. The piperidine ring of the 3,4-di-hydro-quinolin-2(1H)-one moiety has a screw-boat conformation, while the piperazine ring has a chair conformation. In the biaryl group, the pyridine ring is inclined to the phenyl ring by 40.17 (7) and by 36.86 (8)° to the aromatic ring of the quinoline moiety. In the crystal, the cations are linked by pairwise N-H⋯O hydrogen bonds, forming inversion dimers enclosing an R 2 2(8) ring motif. The Cl- anion is linked to the cation by an N-H⋯Cl hydrogen bond. These units are linked by a series of C-H⋯O, C-H⋯N and C-H⋯Cl hydrogen bonds, forming layers lying parallel to the ab plane.

20.
Chemistry ; 27(23): 6973-6984, 2021 Apr 21.
Artigo em Inglês | MEDLINE | ID: mdl-33609404

RESUMO

Tungsten oxide/graphene hybrid materials are attractive semiconductors for energy-related applications. Herein, we report an asymmetric supercapacitor (ASC, HRG//m-WO3 ASC), fabricated from monoclinic tungsten oxide (m-WO3 ) nanoplates as a negative electrode and highly reduced graphene oxide (HRG) as a positive electrode material. The supercapacitor performance of the prepared electrodes was evaluated in an aqueous electrolyte (1 m H2 SO4 ) using three- and two-electrode systems. The HRG//m-WO3 ASC exhibits a maximum specific capacitance of 389 F g-1 at a current density of 0.5 A g-1 , with an associated high energy density of 93 Wh kg-1 at a power density of 500 W kg-1 in a wide 1.6 V operating potential window. In addition, the HRG//m-WO3 ASC displays long-term cycling stability, maintaining 92 % of the original specific capacitance after 5000 galvanostatic charge-discharge cycles. The m-WO3 nanoplates were prepared hydrothermally while HRG was synthesized by a modified Hummers method.

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