Synthesis and Mechanism of Spherical Ag-doped Polypyrrole Assisted by Complexing Agents

Mapping Intimacies ◽

10.21203/rs.3.rs-389009/v1 ◽

2021 ◽

Author(s):

Chuanyun Wan ◽

Xiaoge Chen ◽

Xiya Liu

Keyword(s):

Oxidative Polymerization ◽

Functional Materials ◽

Trisodium Citrate ◽

Structure Characterization ◽

Complexing Agents ◽

Formation Mechanisms ◽

Ammonia Treatment ◽

Reaction Stage ◽

Positive Ions

Abstract Highly dispersed Ag-doped PPy spherical composites can be efficiently synthesized visa oxidative polymerization of pyrrole with FeCl3 in an aqueous Ag+-containing solution in the presence of trisodium citrate, followed by concentrated ammonia treatment. However, the formation mechanisms involved in how to control the shape and how to get the metellic Ag0 need further investigation. In order to elucidate the formation mechanisms, the intermediates in different reaction stage were collected and investigated. Combining the experimental phenomenon and the structure characterization of the samples, it was found that citrate ions make a role of complexing Ag+ to produce [Ag3(C6H5O7)n+1]3n− complexes in the early reaction stage, then mainly play a role of steric stabilizer of AgCl micelles and are responsible for the shape tailoring of PPy composite as well as the reduction of Ag+ in the process of ammonia treatment. Evidently, negative-charged AgCl micelles become the main nucleation sites of pyrrole polymerization through the electrostatic attraction between the negative and positive ions. Concentrated ammonia is adopted to eliminate AgCl cores from the precursor of Ag-doped PPy composites obtained by chemical redox reaction and provides an accelerated reaction condition for reduction of Ag+ by reductants (citrate ion or pyrrole monomer). Ag-containing micelles induction method is a facial chemical method to obtain uniform Ag-doped composites and can be broadened to design other Ag-containing functional materials.

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Critical role of nanocomposites at air–water interface: From aqueous foams to foam-based lightweight functional materials

Chemical Engineering Journal ◽

10.1016/j.cej.2021.129121 ◽

2021 ◽

Vol 416 ◽

pp. 129121

Author(s):

Kai Yu ◽

Bin Li ◽

Huagui Zhang ◽

Zhentao Wang ◽

Wei Zhang ◽

...

Keyword(s):

Critical Role ◽

Functional Materials ◽

Water Interface ◽

Aqueous Foams ◽

Air Water Interface

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A Global Review on Short Peptides: Frontiers and Perspectives

Molecules ◽

10.3390/molecules26020430 ◽

2021 ◽

Vol 26 (2) ◽

pp. 430

Author(s):

Vasso Apostolopoulos ◽

Joanna Bojarska ◽

Tsun-Thai Chai ◽

Sherif Elnagdy ◽

Krzysztof Kaczmarek ◽

...

Keyword(s):

Protein Interactions ◽

Targeted Delivery ◽

Swot Analysis ◽

Functional Materials ◽

Great Promise ◽

Short Peptides ◽

Altered Peptide Ligands ◽

Short Peptide ◽

Domains Of Life

Peptides are fragments of proteins that carry out biological functions. They act as signaling entities via all domains of life and interfere with protein-protein interactions, which are indispensable in bio-processes. Short peptides include fundamental molecular information for a prelude to the symphony of life. They have aroused considerable interest due to their unique features and great promise in innovative bio-therapies. This work focusing on the current state-of-the-art short peptide-based therapeutical developments is the first global review written by researchers from all continents, as a celebration of 100 years of peptide therapeutics since the commencement of insulin therapy in the 1920s. Peptide “drugs” initially played only the role of hormone analogs to balance disorders. Nowadays, they achieve numerous biomedical tasks, can cross membranes, or reach intracellular targets. The role of peptides in bio-processes can hardly be mimicked by other chemical substances. The article is divided into independent sections, which are related to either the progress in short peptide-based theranostics or the problems posing challenge to bio-medicine. In particular, the SWOT analysis of short peptides, their relevance in therapies of diverse diseases, improvements in (bio)synthesis platforms, advanced nano-supramolecular technologies, aptamers, altered peptide ligands and in silico methodologies to overcome peptide limitations, modern smart bio-functional materials, vaccines, and drug/gene-targeted delivery systems are discussed.

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Role of the Anilinium Ion on the Selective Polymerization of Anilinium 2-Acrylamide-2-methyl-1-propanesulfonate

Polymers ◽

10.3390/polym13142349 ◽

2021 ◽

Vol 13 (14) ◽

pp. 2349

Author(s):

Alain Salvador Conejo-Dávila ◽

Marco Armando Moya-Quevedo ◽

David Chávez-Flores ◽

Alejandro Vega-Rios ◽

Erasto Armando Zaragoza-Contreras

Keyword(s):

Cyclic Voltammetry ◽

Optical Properties ◽

Thermal Properties ◽

Free Radical ◽

1H Nmr ◽

Molecular Interactions ◽

13C Nmr ◽

Oxidative Polymerization ◽

Cyclic Voltammetry Analysis

The development of anilinium 2-acrylamide-2-methyl-1-propanesulfonate (Ani-AMPS) monomer, confirmed by 1H NMR, 13C NMR, and FTIR, is systematically studied. Ani-AMPS contains two polymerizable functional groups, so it was submitted to selective polymerization either by free-radical or oxidative polymerization. Therefore, poly(anilinium 2-acrylamide-2-methyl-1-propanesulfonic) [Poly(Ani-AMPS)] and polyaniline doped with 2-acrylamide-2-methyl-1-propanesulfonic acid [PAni-AMPS] can be obtained. First, the acrylamide polymer, poly(Ani-AMPS), favored the π-stacking of the anilinium group produced by the inter- and intra-molecular interactions and was studied utilizing 1H NMR, 13C NMR, FTIR, and UV-Vis-NIR. Furthermore, poly(Ani-AMPS) fluorescence shows quenching in the presence of Fe2+ and Fe3+ in the emission spectrum at 347 nm. In contrast, the typical behavior of polyaniline is observed in the cyclic voltammetry analysis for PAni-AMPS. The optical properties also show a significant change at pH 4.4. The PAni-AMPS structure was corroborated through FTIR, while the thermal properties and morphology were analyzed utilizing TGA, DSC (except PAni-AMPS), and FESEM.

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Remediation of mercury-contaminated soils and sediments using biochar: a critical review

Biochar ◽

10.1007/s42773-021-00087-1 ◽

2021 ◽

Author(s):

Qian Yang ◽

Yongjie Wang ◽

Huan Zhong

Keyword(s):

Health Risks ◽

Contaminated Soils ◽

Functional Materials ◽

Redox Conditions ◽

Existing Problems ◽

Soils And Sediments ◽

Underlying Mechanisms ◽

Biochar Amendment

AbstractThe transformation of mercury (Hg) into the more toxic and bioaccumulative form methylmercury (MeHg) in soils and sediments can lead to the biomagnification of MeHg through the food chain, which poses ecological and health risks. In the last decade, biochar application, an in situ remediation technique, has been shown to be effective in mitigating the risks from Hg in soils and sediments. However, uncertainties associated with biochar use and its underlying mechanisms remain. Here, we summarize recent studies on the effects and advantages of biochar amendment related to Hg biogeochemistry and its bioavailability in soils and sediments and systematically analyze the progress made in understanding the underlying mechanisms responsible for reductions in Hg bioaccumulation. The existing literature indicates (1) that biochar application decreases the mobility of inorganic Hg in soils and sediments and (2) that biochar can reduce the bioavailability of MeHg and its accumulation in crops but has a complex effect on net MeHg production. In this review, two main mechanisms, a direct mechanism (e.g., Hg-biochar binding) and an indirect mechanism (e.g., biochar-impacted sulfur cycling and thus Hg-soil binding), that explain the reduction in Hg bioavailability by biochar amendment based on the interactions among biochar, soil and Hg under redox conditions are highlighted. Furthermore, the existing problems with the use of biochar to treat Hg-contaminated soils and sediments, such as the appropriate dose and the long-term effectiveness of biochar, are discussed. Further research involving laboratory tests and field applications is necessary to obtain a mechanistic understanding of the role of biochar in reducing Hg bioavailability in diverse soil types under varying redox conditions and to develop completely green and sustainable biochar-based functional materials for mitigating Hg-related health risks.

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Role of complexing agents on the etching characteristics of Bi-Sb alloy single crystals

Journal of Crystal Growth ◽

10.1016/0022-0248(80)90048-2 ◽

1980 ◽

Vol 48 (3) ◽

pp. 483-485

Author(s):

V.P. Bhatt ◽

A.R. Vyas ◽

G.R. Pandya

Keyword(s):

Single Crystals ◽

Complexing Agents

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The Influence of Surface Proximity on Photoswitching Activity of Stilbene-Functionalized N-Heterocyclic Carbene Monolayers

Chemical Communications ◽

10.1039/d1cc02491d ◽

2021 ◽

Author(s):

Shahar Dery ◽

Israel Alshanski ◽

Evgeniy Mervinetsky ◽

Daniel Feferman ◽

Shlomo Yitzchaik ◽

...

Keyword(s):

Self Assembly ◽

Crucial Role ◽

Functional Materials ◽

Adsorption Geometry ◽

Surface Proximity

Self-assembly of photo-responsive molecules is a robust technology for reversibly tuning the properties of functional materials. Herein, we probed the crucial role of surface-adsorbate interactions on the adsorption geometry of...

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The Maintenance of Holiness and the Contours of Leadership: Form and Characterization in the Book of Numbers

10.5642/cguetd/207 ◽

2021 ◽

Author(s):

◽

Nathan Daily

Keyword(s):

Critical Theory ◽

21St Century ◽

Biblical Studies ◽

Structure Characterization ◽

Biblical Text ◽

Methodological Study ◽

New Developments ◽

Divine Violence ◽

Literary Setting

The book of Numbers presents numerous problems for interpreters who attempt to garner a sense of meaning from the disparate texts and genres found interspersed throughout the work. This dissertation is a methodological study that incorporates features of form-critical theory, which developed over the course of the 20th century and continues to evolve in the 21st century, alongside literary approaches to the biblical text, specifically the analysis of characterization, to present a new reading of the book of Numbers. After surveying recent research on the book of Numbers, new developments in form-critical method, and approaches to characterization in biblical studies, the work offers a methodological proposal for reading Numbers along synchronic lines, according to the rubrics of structure, characterization, and literary setting. The approach analyzes the form rather than the formation of the text, and, by highlighting the role of characterization within the form-critical enterprise, provides a reading that considers the structure and flow of the book of Numbers as well as, through intertextual readings, the significance of Numbers in the broader structure of the Torah. The remainder of the work analyzes four texts from the book of Numbers: The Commission of the Levites (3:5-51); The Purification of the Levites (8:5-22); The Three-Day Journey from Sinai (10:33-11:34); and The Complaint of Miriam and Aaron (11:35-12:15). Each text is read in relation to the dominant structural marker of the Torah, the toledoth formula, and, particularly, the final formulaic marker in 3:1. Each of the four texts presents a model of Judean leadership set in a narrative that sequentially builds by using the Levites as characters that are assigned roles and appear as illustrations for additional roles necessary to maintain holiness in the camp. As the Torah is structured as a creation text (Gen 1-2; Exod 40:17), the dissertation finds that material in Numbers, which follows the completion of the creation narrative in Exod 40:17 by resetting the narrative chronologically to the same time (Num 3:1; 7:1; 9:15; cf. 1:1), is designed to illustrate the levitical task to maintain creation through attending to holiness. Now that creation has reached completion with the dangerous presence of the holy deity residing within Israel, proper management under proper leadership will result in blessing, but inattentiveness to holiness by the leadership or others is liable to incite danger. The new reading attends to discussions of structure, plot, and coherence in Numbers as well as theological concerns related to leadership, holiness, and divine violence.

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Regeneration and pattern formation in planarians. II. and role of cell movements in blastema formation

Development ◽

10.1242/dev.107.1.69 ◽

1989 ◽

Vol 107 (1) ◽

pp. 69-76 ◽

Cited By ~ 1

Author(s):

E. Salo ◽

J. Baguna

Keyword(s):

Pattern Formation ◽

Cell Movement ◽

Formation Mechanisms ◽

Blastema Formation ◽

Chromosomal Markers ◽

Undifferentiated Cells ◽

Local Cell ◽

Number Of Cells ◽

Wound Epithelium

In planarians, blastema cells do not divide, and growth blastema is thought to result from the steady wound epithelium, of undifferentiated cells produced in the stump. However, whether these cells come only sources or whether cells placed far from the wound can participate, after long-range migrations, in the still uncertain. To study this problem, we have parameters of the process of regeneration: cell growth; number of cells produced by mitosis in the wound (postblastema); and rates of movement undifferentiated cells using grafting procedures with chromosomal markers. The results show that: (1) cells area spread (move) at higher rates than cells placed (90–140_mday-1 versus 40–50_mday-1); (2) cells than 500_m from the wound boundary are hardly 5-day-old blastemata; and (3) the number of cells within a 200–300_m postblastema area around the wound explain, provided their rates of movement are taken increasing number of blastema cells. From this, it is blastema cells in planarians originate from local mitotic activity jointly with local cell movement postblastema area around the wound match the blastema cells during regeneration. The implications for blastema growth and pattern formation mechanisms

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Role of Trisodium Citrate in the Unclottability by Thrombin of Fibrinogen Metz

10.1055/s-0039-1689371 ◽

1975 ◽

Author(s):

C. Soria ◽

J. Soria ◽

M. Samama ◽

E. Poirot ◽

G. Kling

Keyword(s):

Calcium Chloride ◽

Whole Blood ◽

Blood Clotting ◽

Negative Charge ◽

Trisodium Citrate ◽

Thrombin Time ◽

Clotting Time ◽

Fibrin Formation ◽

Blood Clotting Time

In a case of homozygous dysfibrinogenemia, the whole blood clotting time was moderately prolonged, while the thrombin clotting time was infinite, whatever dose or nature of thrombin used. Besides, the bleeding syndrome in this case was very weak.We observed also that only after trisodium citrate addition to purified fibrinogen, the abnormal fibrinogen became unclottable by thrombin even after addition of calcium chloride, since without trisodium citrate thrombin time was only prolonged.By immunoelectrophoresis and by isofocusing in the presence or in the absence of trisodium citrate, we therefore undertook to show that trisodium citrate reacts more strongly with the abnormal fibrinogen than with normal one. Thus, trisodium citrate conferring a negative charge to the pathological molecule, the abnormal fibrinogen became resistant to clotting with thrombin. Protamine sulfate, by positiving the charges of fibrinogen, partially corrects the defect in fibrin formation.

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