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1.
Inorg Chem ; 63(10): 4527-4544, 2024 Mar 11.
Artigo em Inglês | MEDLINE | ID: mdl-38408204

RESUMO

Here, electrical conductivity and explosive sensing properties of multifunctional chromone-Cd(II)-based coordination polymers (CPs) (1-4) have been explored. The presence of different pseudohalide linkers, thiocyanate ions, and dicyanamide ions resulted in 1D and 3D architecture in the CPs. Thin film devices developed from CPs 1-4 (complex-based Schottky devices, CSD1, CSD2, CSD3, and CSD4, respectively) showed semiconductor behavior. Their conductivity values increased under photo illumination (1.37 × 10-5, 1.85 × 10-5, 1.61 × 10-5, and 2.01 × 10-5 S m-1 under dark conditions and 5.06 × 10-5, 8.78 × 10-5, 7.26 × 10-5, and 10.21 × 10-5 S m-1 under light). The nature of the I-V plots of these thin film devices under light irradiation and dark are nonlinear rectifying, which has been observed in Schottky barrier diodes (SBDs). All four CPs (1-4) exhibited highly selective fluorescence quenching-based sensing properties toward well-known explosives, 2,4-dinitrophenol (DNP) and 2,4,6-trinitrophenol (TNP). The limit of detection (LOD) values are 55, 28, 27, and 31 µM for TNP and 78, 44, 32, and 41 µM for DNP for complexes 1-4, respectively. A structure property correlation has been established to explain optoelectronic and explosive sensing properties.

2.
Langmuir ; 39(21): 7469-7483, 2023 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-37192598

RESUMO

The importance of three synthesized metallogels of suberic acid distinctly with nickel, zinc, and cadmium acetate salts has been uncovered. For the creation of these soft materials, N,N'-dimethyl formamide was utilized as a source of the trapped solvent. The synthesized metallogels display intriguing viscoelasticity, and the interpretation of experimental parameters obtained from rheological results advocates the gel behavior. Microstructural analysis combined with energy-dispersive X-ray confirms the occurrence of individual gel-developing constituents as observed in different hierarchical microstructural patterns. Significant variations in microstructural arrangements with diverse extent of supramolecular non-covalent patterns inside gel networks were perceived through field emission scanning electron microscopy, atomic force microscopy, and transmission electron microscopy analyses. Fourier transform infrared and electrospray ionization-mass spectral analyses and powder X-ray diffraction analysis of metallogel samples of different gel-establishing ingredients help to investigate the possible supramolecular interactions dictating the metallogel scaffolds. Thermogravimetric analysis of xerogel samples was collected from the synthesized metallogels to understand the thermal stability. These gel materials were characterized by their potential antibacterial efficiency. The potency of metallogels against selective Gram-positive and Gram-negative bacteria was visualized via a spectrophotometer. Human pathogens like Klebsiella pneumoniae (MTCC 109), Salmonella typhi (MTCC 733), Vibrio parahaemolyticus, Bacillus cereus (MTCC 1272), Lactobacillus fermentum (NCDO 955), and Staphylococcus aureus (MTCC 96) are employed in this study. Apart from the biological significance, our metallogels demonstrate as incredible diode performance of fabricated semiconducting systems, which exhibit a considerable amount of non-linearity demonstrating a non-ohmic conduction mechanism at room temperature in dark conditions. Device fabrication was achieved from these metallogels employing the sandwich model with indium tin oxide-coated glass substrates/metallogel/Al structure.

3.
Inorg Chem ; 62(32): 12773-12782, 2023 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-37531605

RESUMO

Pyridyl-substituted imidazoquinoline, a potent fluorescent framework, is advantageous to architect multifunctional coordination networks for sensing and fabricating emergent electrical conductors. In this work, a Cd(II)-based one-dimensional (1D) coordination polymer (1D CP), [Cd(glu)2(pbiq)2(H2O)]n (1), [H2glu = glutaric acid and pbiq = 4-(6-(pyridin-4-yl)benzo[4,5]imidazo[1,2-c]quinazoline)], has been structurally confirmed by single-crystal X-ray crystallography. The H-bonding and π···π interactions built a three-dimensional (3D) supramolecular structure that strongly emits at 416 nm in acetonitrile suspension. Potentially intrusive nitroaromatics (NAs) and trinitrophenol (TNP) selectively quench the strong emission of 1, and the highest quenching is noted in the case of TNP. A detection limit (limit of detection (LOD)) of 1.51 × 10-7 M for TNP is determined. The band gap (3.31 eV) of 1 recognizes semiconducting behavior, and an electronic device is fabricated. The correlation of current vs voltage (I-V plot) reveals a substantial non-ohmic electrical conductivity of 1 (Λ: 1.10 × 10-5 S m-1) along with a low energy barrier (ΦB: 0.69), and the series resistance (Rs) becomes 6.21 kΩ.

4.
Aesthetic Plast Surg ; 2023 Dec 28.
Artigo em Inglês | MEDLINE | ID: mdl-38155290

RESUMO

In this letter to the editor, I offer a critique of the article titled "Consulting the Digital Doctor: Google Versus ChatGPT as Sources of Information on Breast Implant-Associated Anaplastic Large Cell Lymphoma and Breast Implant Illness." While acknowledging the authors' pioneering effort to compare informational outputs from Google and a generative AI (GAI)-ChatGPT, I raise concerns about the methodology, lack of rigorous validation, potential biases, and the overstatement of findings. The letter suggests that the authors' conclusions about the superiority of ChatGPT in providing high-quality medical information may be premature, given the limitations of the study design and the evolving nature of artificial intelligence (AI) technology.No Level Assigned This journal requires that authors assign a level of evidence to each submission to which Evidence-Based Medicine rankings are applicable. This excludes Review Articles, Book Reviews, and manuscripts that concern Basic Science, Animal Studies, Cadaver Studies, and Experimental Studies. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266.

5.
Inorg Chem ; 61(49): 19828-19837, 2022 Dec 12.
Artigo em Inglês | MEDLINE | ID: mdl-36427262

RESUMO

Four new Cu(II)-based hexagonal complexes with the metallomacrocycle formulae [Cu6(5-nip)6(3-py)6(H2O)12] (1), [Cu6(5-nip)6(3-Clpy)6(H2O)12] (2), [Cu6(5-nip)6(3-Brpy)6(H2O)12] (3), and [Cu6(5-nip)6(3-Ipy)6(H2O)12] (4) have been synthesized using 5-nitroisophthalic acid (H25-nip) and pyridine (py)/3-halopyridine (3-Xpy; X = Cl, Br, and I) ligands. The structural features and supramolecular interactions of compounds 1-4 have been investigated using the single-crystal X-ray diffraction (SCXRD) technique. Interestingly, the hexagonal complexes undergo hydrogen bonding and π···π stacking interactions to form fascinating two-dimensional (2D) honeycomb-like structures. The synthesized complexes exhibit high electrical conductivity, arising from charge transport through space via π···π contacts. However, complexes containing 3-Brpy (3) and 3-Ipy (4) exhibit photosensitivity due to the presence of halogens with a larger size and lower ionization energy. The conductivity results are also in accordance with the theoretical prediction calculated by density functional theory (DFT) study.


Assuntos
Cobre , Cobre/química , Modelos Moleculares , Cristalografia por Raios X , Ligantes , Ligação de Hidrogênio
7.
Inorg Chem ; 59(8): 5518-5528, 2020 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-32216339

RESUMO

A heteroporous metal-organic framework, [Cd2(2,2'-DSB)2(INH)2(H2O)2]n (1), is fabricated by the reaction of CdI2, 2-mercaptobenzoic acid (2-MBAH), and isoniazid (INH). The X-ray structure of the compound 1 shows the bridging INH and 2,2'-disulfanediyldibenzoic acid (H22,2'-DSBA) around the Cd(II) ion center. 2-MBAH has been in situ dimerized to the formation of 2,2'-DSB2- (S-S-bonded dianion), which has further extended to form the 2D network. However, supramolecular assembly via π···π and hydrogen bonds strengthens the structural motif within the 3D array. Optical stimulation generated the thiol radical under an argon environment followed by the electron paramagnetic resonance (EPR) study, but upon exposure to air, the EPR signal gradually disappeared by the formation of the S-S bond, which was commonly known as a self-healing property. Again, compound 1 exhibited as a semiconducting material with a band gap of 3.7 eV. The I-V characteristics of 1 show that the conductivity is intensified by an optical response. The Schottky diode property of 1 shows a lower barrier height, a lower resistance, and a higher conductivity upon illumination at 360 nm.

8.
Inorg Chem ; 59(13): 8749-8761, 2020 Jul 06.
Artigo em Inglês | MEDLINE | ID: mdl-32520535

RESUMO

The combination of two 8-aminoquinoline-based Schiff base ligands (L1 and L2) with SCN- and Ni(II) has led to the synthesis of two new one-dimensional thiocyanato-bridged coordination polymers: [Ni(L1)(NCS)2]n (1) and [Ni(L2)(NCS)2]n (2). Both compounds are isostructural and consists of regular zigzag thiocyanato-bridged chains with very weak S···S interchain interactions. The measured room-temperature conductivities of compounds 1 and 2 (7.0 × 10-5 and 2.0 × 10-5 S m-1, respectively) are indicative of semiconductor behavior which increases in the presence of photoillumination (3.5 × 10-4 and 4.9 × 10-4 S m-1, respectively). The measured I-V characteristics of compound 1 and 2 based thin film metal-semiconductor (MS) junction devices under irradiation and nonirradiation conditions show a nonlinear rectifying behavior, typical of a Schottky diode (SD). The rectification ratios (Ion/Ioff) of the SDs in the dark at ±2 V (26.96 and 31.96 for 1- and 2-based devices, respectively) increase to 44.19 and 79.42, respectively, upon light irradiation. The photoinduced behavior has been analyzed by thermionic emission theory, and to determine the diode parameters, the Cheung's method has been employed. These diode parameters indicate that compound 2 has a better performance in comparison to compound 1 and that these materials are good candidates for applications in electrochemical devices. Magnetic measurements show that both compounds present ferromagnetic Ni-Ni intrachain and weak antiferromagnetic interchain interactions. The isothermal magnetizations at 2 K show that both compounds are metamagnets with critical fields of ca. 130 mT in 1 and 90 mT in 2 at 2 K. In the ferromagnetic phase (above the critical field), both compounds exhibit a long-range ferromagnetic order with critical temperatures of around 3.5 K in 1 and 3.0 K in 2. DC and AC measurements with different applied DC fields confirm the metamagnetic behaviors and have allowed the determination of the magnetic phase diagram in both compounds.

10.
J Hepatol ; 80(1): e28-e29, 2024 01.
Artigo em Inglês | MEDLINE | ID: mdl-37595847
11.
Inorg Chem ; 58(9): 5419-5422, 2019 May 06.
Artigo em Inglês | MEDLINE | ID: mdl-30978011

RESUMO

A metal-organic compound [Cd(quin)2(4-nvp)2] [1; Hquin = quinoline-2-carboxylic acid and 4-nvp = 4-(1-naphthylvinyl)pyridine] undergoes topochemical [2 + 2] cycloaddition by sunlight irradiation to generate a one-dimensional coordination polymer. This reaction is thermally reversible, and switching between two crystalline forms can be monitored by conductivity measurements.

12.
Inorg Chem ; 58(4): 2686-2694, 2019 Feb 18.
Artigo em Inglês | MEDLINE | ID: mdl-30698955

RESUMO

A novel mixed ligand one-dimensional coordination polymer (1D CP), {[Cd2(adc)2(4-nvp)6]·(MeOH)·(H2O)} n (1; H2adc = 9,10-anthracenedicarboxylic acid, and 4-nvp = 4-(1-naphthylvinyl)pyridine), has been synthesized and structurally characterized by single crystal X-ray crystallography. The 1D polymer undergoes supramolecular aggregation via hydrogen bonding, C-H···π, and π···π interactions. Interestingly, compound 1 shows increasing conductivity upon irradiation of light. Therefore, it has the potential to be used in optoelectronic devices. Moreover, the supramolecular assembly of 1 specifically detects Cr3+ cation in the presence of other competitive analytes. Most importantly, compound 1 exhibits fascinating turn-on Cr3+ sensing, which seems to be an ornament in the field of sensing application.

14.
Ophthalmic Physiol Opt ; 44(1): 231-232, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37635304
17.
J Med Syst ; 43(9): 287, 2019 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-31317281

RESUMO

In today's world, 46.8 million people suffer from brain related diseases. Dementia is most prevalent of all. In general scenario, a dementia patient lacks proper guidance in searching out the way to return back at his/her home. Thus, increasing the risk of getting damaged at individual-health level. Therefore, it is important to track their movement in more sophisticated manner as possible. With emergence of wearables, GPS sensors and Internet of Things (IoT), such devices have become available in public domain. Smartphone apps support caregiver to locate the dementia patients in real-time. RF, GSM, 3G, Wi-Fi and 4G technology fill the communication gap between patient and caregiver to bring them closer. In this paper, we incorporated 7 most popular wearables for investigation to seek appropriateness for dementia tracking in recent times in systematic manners. We performed an in-depth review of these wearables as per the cost, technology wise and application wise characteristics. A case novel study i.e. IoT-based Force Sensor Resistance enabled System-FSRIoT, has been proposed and implemented to validate the effectiveness of IoT in the domain of smarter dementia patient tracking in wearable form factor. The results show promising aspect of a whole new notion to leverage efficient assistive physio-medical healthcare to the dementia patients and the affected family members to reduce life risks and achieve a better social life.


Assuntos
Demência/epidemiologia , Dispositivos Eletrônicos Vestíveis/normas , Fontes de Energia Elétrica , Sistemas de Informação Geográfica , Humanos , Aplicativos Móveis , Interface Usuário-Computador , Dispositivos Eletrônicos Vestíveis/economia
20.
Radiology ; 308(2): e231696, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37526538

Assuntos
Radiologia , Humanos
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