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The total oxidizable precursor (TOP) assay has been extensively used for detecting PFAS pollutants that do not have analytical standards. It uses hydroxyl radicals (HO•) from the heat activation of persulfate under alkaline pH to convert H-containing precursors to perfluoroalkyl carboxylates (PFCAs) for target analysis. However, the current TOP assay oxidation method does not apply to emerging PFAS because (i) many structures do not contain C-H bonds for HO• attack and (ii) the transformation products are not necessarily PFCAs. In this study, we explored the use of classic acidic persulfate digestion, which generates sulfate radicals (SO4-•), to extend the capability of the TOP assay. We examined the oxidation of Nafion-related ether sulfonates that contain C-H or -COO-, characterized the oxidation products, and quantified the F atom balance. The SO4-• oxidation greatly expanded the scope of oxidizable precursors. The transformation was initiated by decarboxylation, followed by various spontaneous steps, such as HF elimination and ester hydrolysis. We further compared the oxidation of legacy fluorotelomers using SO4-• versus HO•. The results suggest novel product distribution patterns, depending on the functional group and oxidant dose. The general trends and strategies were also validated by analyzing a mixture of 100000- or 10000-fold diluted aqueous film-forming foam (containing various fluorotelomer surfactants and organics) and a spiked Nafion precursor. Therefore, (1) the combined use of SO4-• and HO• oxidation, (2) the expanded list of standard chemicals, and (3) further elucidation of SO4-• oxidation mechanisms will provide more critical information to probe emerging PFAS pollutants.

This study presents an innovative approach using the Ethereum blockchain to democratize access to tutoring services, advancing educational technology by bridging the affordability gap for learners with limited financial resources. This solution enables low-income learners to access tutoring services without significant expenses by eliminating intermediaries through smart contracts. Learners can directly book tutoring services based on fees and evaluations, ensuring a fair and accessible experience. The findings show that this approach reduces tutoring expenses and improves trust and accountability through transparent transactions and feedback mechanisms. The proposed system demonstrates how blockchain technology can foster a more equitable and efficient educational landscape, offering personalized support to all learners regardless of their economic background. [ABSTRACT FROM AUTHOR]

High‐energy‐density lithium metal batteries (LMBs) hold enormous potential for future energy storage systems but are plagued by poor cycling stability and safety concerns, especially under high‐rate conditions. The addition of fluorinated solvents to the electrolyte is effective in enhancing the stability of the lithium metal anode (LMA) and improving safety for LMBs. However, the extensive introduction of fluorinated solvents is not conducive to the transport of lithium‐ions (Li+), thereby negatively affecting the rate performance of LMBs. Herein, a safe ether electrolyte (SEE) is designed that exhibits both high Li+ conductivity and nonflammability, while maintaining high compatibility with the LMA. Li–LiNi0.8Mn0.1Co0.1O2 (NMC811) cells utilizing SEE can demonstrate remarkable electrochemical performance, delivering a discharge capacity of 113.1 mAh g⁻¹ at rates as high as 30 C and maintaining 90% of their initial capacity over 300 cycles at 10 C. Moreover, a practical Li‐NCM811 full cell assembled with SEE achieves stable cycling at 3 C. [ABSTRACT FROM AUTHOR]

A single-step phenylation at the non-acidic C(sp3)–H bond attached to the heteroatom of ethers and N -Boc-amines has been achieved using photoexcited 4-benzoylpyridine as a hydrogen atom transfer (HAT) catalyst. The design of electron-deficient (trifluoromethylsulfonyl)benzene derivatives, as a phenyl precursor, was critical to realizing the present transformation. Moreover, the DFT calculations indicated that the present transformation proceeds via a concerted homolytic aromatic substitution rather than via a stepwise one involving the formation of a cyclohexadienyl radical intermediate. [ABSTRACT FROM AUTHOR]

Abstract This article is devoted to the synthesis of a new magnetic palladium catalyst that has been immobilized on A-TT-Pd coated-magnetic Fe3O4 nanoparticles. Such surface functionalization of magnetic particles is a promising method to bridge the gap between heterogeneous and homogeneous catalysis approaches. The structure, morphology, and physicochemical properties of the particles were characterized through different analytical techniques, including TEM, FT-IR, XRD, SEM, EDS, TGA-DTG, ICP, and VSM techniques. The obtained Fe3O4@SiO2@A-TT-Pd performance can show excellent catalytic activity for the synthesis of diaryl ethers and oxidation of sulfides, and the corresponding products were obtained with high yields. The advantages of this catalyst include a simple test method, green reaction conditions, no use of dangerous solvents, short reaction time, low catalyst loading, and reusability. Also, the nanocatalyst was easily separated from the reaction mixture with the help of a bar magnet and recovered and reused several times without loss of stability and activity.

Poly-ether-ether-ketone (PEEK) and PEEK composites are outstanding candidates for biomedical applications, such as orthopedic devices, where biocompatibility and modulus match with surrounding tissue are requisite for long-term success. The mechanical properties can be optimized by incorporating fillers such as continuous and chopped carbon fibers. While much is known about the mechanical and tribological behavior of PEEK composites, there are few articles that summarize the viability of using PEEK reinforced with carbon fibers in orthopedic implants. This paper reviews biocompatibility, tribological, and mechanical studies on PEEK and their composites with carbon fibers, notably PEEK reinforced with polyacrylonitrile (PAN)-based carbon fibers and PEEK reinforced with pitch-based carbon fibers, for application in orthopedics and total joint replacements (TJRs). The main objectives of this review are two-fold. Firstly, this paper aims to assist designers in making informed decisions on the suitability of using PEEK and PEEK composites in orthopedic applications; as it is not well understood how these materials perform on the whole in orthopedics and TJRs. Secondly, this paper aims to serve as a centralized paper in which researchers can gain information on the tribological and mechanical advancements of PEEK and PEEK composites.

Accessing versatile C(sp3)−C(sp3) bond through the cross‐electrophile coupling of two distinct etheric C−O bonds is crucial in organic synthesis but remains barely explored. Herein, we report an innovative photoinduced low‐valent zirconocene catalysis enabling the reductive coupling of ethers with high activity and cross‐selectivity. Mechanistic investigation suggests that photoexcitation of low‐valent zirconocene facilitates the C(sp3)−O bond scission of benzylic ethers, leading to the benzylic radicals intermediate via a single‐electron reduction pathway. The subsequent recombination of this benzylic radical with the Zr center followed by carbomagnesiation generates benzylic Grignard reagents for downstream coupling with aliphatic ethers through an SN2‐like mechanism. In application, a wide range of ethers readily in situ derived from aldehydes and ketones becomes feasible with high functional group compatibility as well as excellent cross‐selectivity. [ABSTRACT FROM AUTHOR]

Sodium-ion batteries (SIBs) as one of the promising alternatives to lithium-ion batteries have achieved remarkable progress in the past. However, the all-climate performance is still very challenging for SIBs. Herein, 15-Crown-5 (15-C-5) is screened as an electrolyte additive from a number of ether molecules theoretically. The good sodiophilicity, high molecule rigidity, and bulky size enable it to reshape the solvation sheath and promote the anion engagement in the solvated structures by molecule crowding. This change also enhances Na-ion transfer, inhibits side reactions, and leads to a thin and robust solid-electrolyte interphase. Furthermore, the electrochemical stability and operating temperature windows of the electrolyte are extended. These profits improve the electrochemical performance of SIBs in all climates, much better than the case without 15-C-5. This improvement is also adopted to μ-Sn, μ-Bi, hard carbon, and MoS2. This work opens a door to prioritize the potential molecules in theory for advanced electrolytes. [ABSTRACT FROM AUTHOR]

We synthesised selenium-linked liquid crystal dimers and examined their phase behaviour to determine the effects of chalcogen linkage and spacer length on the formation of a twist-bend nematic (NTB) phase. Two new homologous series of nonsymmetric selenoether- and ether- or thioether-linked cyanobiphenyl-based dimers (CBSenOCB and CBSenSCB, respectively) comprising an alkyl spacer chain with a carbon number (n) of 3, 5, 6, 7, 9, and 11 were developed. We also synthesised n = 6 and 11 of previously reported symmetrically selenoether-linked CBSenSeCB homologues. Conventional nematic (N) and NTB phases were observed for nearly all odd-n CBSenSeCB, CBSenOCB, and CBSenSCB dimers. The phase transition behaviours of the three homologous series were compared with those of the known symmetric ether-linked CBOnOCB, thioether-linked CBSnSCB, and asymmetric thioether- and ether-linked CBSnOCB dimers. Replacing ether with thioether or selenoether resulted in lower LC phase-transition temperatures, particularly for selenoether. Single-crystal structural analyses revealed that CBS3SCB and CBSe3SeCB exhibited folded U-shaped molecular shapes that were bent more than the V-shapes of CBOnOCB (n = 3 and 5) and CBS5SCB. In addition, thioether and selenoether linkages rendered the molecular forms of odd-spacer dimers in the crystals more bent. [ABSTRACT FROM AUTHOR]

Modified polystyrenes having tertiary ether linkages or carbonate linkages were degrade by irradiation of near‐infrared light (NIR) and subsequent heating. The polymer films containing a photoacid generator and commercially available photon upconversion nanoparticle (UCNP) were decomposed to form isobutene and/or carbon dioxide by irradiation of NIR and subsequent heating. The thermal decomposition behaviors of the polymers were investigated and discussed in terms of the chemical structures of degradable units. The thermal stability of the polymers was found to be in the order: tertiary ester > tertiary carbonate. We believe that the degradation of NIR and subsequent heating contributes easy recycling of composite materials. [ABSTRACT FROM AUTHOR]

Copyright of Revista Foco (Interdisciplinary Studies Journal) is the property of Revista Foco and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Molecules containing ether skeletons are widely present in drugs, natural products, functional materials, and life science. Direct C(sp3)−H bond ether functionalization is considered a powerful strategy for the construction of novel ether derivatives. Photo‐/electro‐chemical technology is a relatively green and sustainable synthesis method, which opens up a broad application prospect in the field of direct functionalization of C(sp3)−H bonds. In recent years, photo‐/electro‐mediated C(sp3)−H bond alkylation, arylation, alkynylation, esterification, mercaptoylation, sulfidation, and amination of ethers have been extensively studied. In this review, the research progress of photo‐/electro‐mediated C(sp3)−H bond functionalization of ether compounds from 2014 to 2023 is systematically reviewed, and the scope, limitations, and mechanisms for some reactions are discussed. [ABSTRACT FROM AUTHOR]

Copyright of Turkiye Klinikleri Journal of Medical Ethics-Law & History / Türkiye klinikleri tıp Etiği, Hukuku ve Tarihi Dergisi is the property of Turkiye Klinikleri and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

We report a metal‐free method for benzylic C(sp3)−H alkoxylation with a silyl ether as an alkoxylating agent. The reaction is considered to proceed through a sequence consisting of hydrogen atom transfer (HAT) and oxidative radical‐polar crossover, wherein Selectfluor serves as a one‐electron oxidant, a HAT agent, and a fluoride ion source. The fluoride ion formed in situ activates the silyl ether to give the alkoxide nucleophile, which reacts with a benzyl cation intermediate to provide the benzyl ether product. The present protocol has a broad substrate scope, enabling C−H alkoxylation of primary, secondary, and tertiary benzylic C(sp3)−H bonds. Furthermore, it is applicable for late‐stage C−H alkoxylation of bioactive molecules. [ABSTRACT FROM AUTHOR]

Copyright of Oilfield Chemistry is the property of Sichuan University, Oilfield Chemistry Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

George Francis FitzGerald is well known to have proposed in 1889, three years before Lorentz, the (physical) contraction of bodies moving in the hypothetical ether, as an “explanation” the null result of the Michelson and Morley experiment. Less known is his proposal of an ether-drift experiment based on an electrostatic system. A simple charged condenser suspended by a wire would be subject to a torque due to the earth’s motion. The experiment was done by his pupil Trouton, with Noble, with null result. It was an important independent confirmation of the relativity principle, but it was substantially forgotten. It came back, under the form of a paradox, in the second half of the past century, usefully triggering an in-depth discussion on the electromagnetic energy and momentum flow in stationary systems, in which intuitively one thinks momentum should be zero, but it is not. The solution of the Trouton–Noble paradox, and similar ones, has led to a better understanding of the interplay between electromagnetic field and matter and to develop relevant examples for the university courses. [ABSTRACT FROM AUTHOR]

The blossoming of cryptocurrencies during the last decade has largely influenced both the financial and the technological world. Bitcoin emerged on the edge of the financial crisis in 2008, signaling the very beginning of a financial and technological innovation, which in continuance would eventually create a lot of questions and debate previously unforeseeable. This paper aims to explore the impact of factors such as trading volume, information demand, stock returns, and exchange rates on the volatility of returns for decentralized and unbacked cryptocurrencies from 2016 to 2022 by employing the GARCH model. Based on each coin's innate functional characteristics and market performance quantified by their respective market capitalization, the selection included Bitcoin, Ether, and XRP as representative crypto coins for the category of decentralized and unbacked cryptocurrencies. The implementation of correlation analysis and the use of the GARCH model on influencing factors for each coin revealed that decentralized and unbacked cryptocurrencies are positively related to trading volume, information demand, and exchange rates while being indifferent to a certain extent to the stock market returns of the world stock index MSCI ACWI. The results of this study provide further insight into the behavior of cryptocurrency return volatility in the new, ever-changing, and highly unpredictable crypto market as well as aid investors in their decision-making process concerning portfolio optimization. [ABSTRACT FROM AUTHOR]

We study recurrent patterns in volatility and volume for major cryptocurrencies, Bitcoin and Ether, using data from two centralized exchanges (CEXs; Coinbase Pro and Binance) and a decentralized exchange (DEX; Uniswap V2). We find systematic patterns in both volatility and volume across day-of-the-week, hour-of-the-day, and within the hour. These patterns have grown stronger over the years and are presumably related to algorithmic trading and funding times in futures markets. We also document that price formation mainly takes place on the CEXs while price adjustments on the DEXs can be sluggish. [ABSTRACT FROM AUTHOR]

Ethereum is being utilized in various ways, including smart contracts and payments. Research in cryptocurrency payments has either been general, about all cryptocurrencies or focused primarily on Bitcoin. Despite some similarities with Bitcoin, Ethereum is a different technology with different governance and support. This research focuses on payments with the Ethereum token, Ether, and puts forward a model of trust in Ethereum payments. Survey data analyzed using structural equation modeling supports the model. Firstly, the model has three variables from the person's individual characteristics: The user's predisposition to using innovations in (a) finance and (b) technology, influence (c) their predisposition to trust in this payment process. There are then five variables from the context: (d) Adoption and reputation, (e) stable value and low transaction fees, (f) effective regulation, (g) trust in the payment intermediaries, and (h) trust in the seller. The personal and contextual factors together influence (i) trust in the Ethereum payment process, and this leads to (j) making a payment with Ethereum. [ABSTRACT FROM AUTHOR]

Ethereum is being utilized in various ways, including smart contracts and payments. Research in cryptocurrency payments has either been general, about all cryptocurrencies or focused primarily on Bitcoin. Despite some similarities with Bitcoin, Ethereum is a different technology with different governance and support. This research focuses on payments with the Ethereum token, Ether, and puts forward a model of trust in Ethereum payments. Survey data analyzed using structural equation modeling supports the model. Firstly, the model has three variables from the person’s individual characteristics: The user’s predisposition to using innovations in (a) finance and (b) technology, influence (c) their predisposition to trust in this payment process. There are then five variables from the context: (d) Adoption and reputation, (e) stable value and low transaction fees, (f) effective regulation, (g) trust in the payment intermediaries, and (h) trust in the seller. The personal and contextual factors together influence (i) trust in the Ethereum payment process, and this leads to (j) making a payment with Ethereum.

Ether derivatives are widespread as essential building blocks in various drugs, natural products, agrochemicals, and materials. Modern economy requires developing green strategies with improved efficiency and reduction of waste. Due to its atom and step-economy, the cross-dehydrogenative coupling (CDC) reaction has become a major strategy for ether functionalization. This review covers C–H/C–H cross-coupling reactions of ether derivatives with various C–H bond substrates via non-noble metal catalysts (Fe, Cu, Co, Mn, Ni, Zn, Y, Sc, In, Ag). We discuss advances achieved in these CDC reactions and hope to attract interest in developing novel methodologies in this field of organic chemistry.

The title compound, systematic name 4,4′,6,6′-tetrachloro-2,2′-{[(2-methoxyethyl)azanediyl]bis(methylene)}diphenol (C17H17Cl4NO, 1), was prepared via a modified Mannich reaction between 2-methoxyethylamine, 2,4-dichlorophenol, and aqueous formaldehyde. The resulting amine bis(phenol) provides an interesting comparison to related species as a result of the electron-withdrawing substituents on the phenol rings, in combination with similar steric parameters. One of the Cl atoms was modeled as a two-component disorder with partial occupancies of 0.49 (3) and 0.51 (3), while the pendant ether group was modeled as a two-component disorder with partial occupancies of 0.867 (3) and 0.133 (3). A comparison of metrical parameters for the title compound and closely related structures provides insight into the use of these species as ligands to support transition-metal complexes for applications as homogeneous catalysts.

Ether‐based electrolytes that are endowed with decent compatibility towards lithium anode have been regarded as promising candidates for constructing energy‐dense lithium metal batteries (LMBs), but their applications are hindered by low oxidation stability in conventional salt concentration. Here, we reported that regulating the chelating power and coordination structure can remarkably increase the high‐voltage stability of ether‐based electrolytes and lifespan of LMBs. Two ether molecules of 1,3‐dimethoxypropane (DMP) and 1,3‐diethoxypropane (DEP) are designed and synthesized as solvents of electrolytes to replace the traditional ether solvent (1,2‐dimethoxyethane, DME). Both computational and spectra reveal that the transition from five‐ to six‐membered chelate solvation structure by adding one methylene on DME results in the formation of weak Li solvates, which increase the reversibility and high‐voltage stability in LMBs. Even under lean electrolyte (5 mL Ah−1) and low anode to cathode ratio (2.6), the fabricated high‐voltage Li||LiNi0.8Co0.1Mn0.1O2 LMBs using electrolyte of 2.30 M Lithiumbisfluorosulfonimide (LiFSI)/DMP still show capacity retention over 90 % after 184 cycles. This work highlights the importance of designing the coordination structures in non‐fluorine ether electrolytes for rechargeable batteries. [ABSTRACT FROM AUTHOR]

In the Middle Persian text of selections of Zādispram, the stages of embryo development, frāz-waxšēnīdar Frawahr power (ether), and the three functions of “germinating,” “adding,” and “caring” create the way of caring for and nurturing the cellular environment. By creating a defense barrier, this power protects the cells against factors that reduce the cell reserve, including differentiation stimuli and apoptosis (programmed cell death) stimuli. The question raised in this research is that according to the stages of evolution (transformation), “how does Frawahr power guard and take care of the development stages of humans before birth and until death?” In other words, the present study aimed to investigate and analyze the theory of “development,” which explains that a cell contributes to the process and stages of embryo development and self-renewal by performing symmetrical division based on the draft and planning of the Frawahr power. The research method was descriptive-analytical, focusing on the attitude of Zādispram about concepts, such as embryo development and genesis. The findings revealed that the Frawahr power and the proliferation potential could prompt the accumulation of cell lines, including embryonic and bone marrow cells; accordingly, the embryonic body causes renewal in humans.

Different starch properties may cause alterations in the foodstuff’s external appearance. However, modification processes in starches are usually secretive. The use of chemically modified starches is regulated by international standards, which makes it important to identify its presence and type. Mid-infrared spectroscopy (MIR)-modified starches’ identification can be hindered by the presence of excess glucose. This research investigates types of modification in commercial starches and in approaches that circumvent MIR’s limitations with exploratory analysis. It also considers that enzymatic hydrolysis (α-amylase and amyloglucosidase) can highlight the points of modification in the structure, which can be detected with infrared assays. To determine if sour cassava starch (FCS) is modified and check its type, six samples were selected: a native one, three of the most common cassava modified starches (etherified, esterified, and FCS), and two laboratory processed samples (Acid, Oxidized). The results showed that the sour cassava starch showed similarities with a commercial ester and an oxidized cassava starch, which may be due to the formation of a graft, corresponding to what the literature has already reported for corn starch treated with lactic acid and gamma radiation.

Room temperature ionic liquids (RTILs) with ether oxygen atoms in the side chain have been investigated for electrochemical applications because they show favorable transport properties compared with alkyl analogs. However, the influence of the position and number of ether oxygen atoms on physical properties has not yet been fully clarified. In the present study, the physicochemical properties of RTILs consisting of bis(trifluoromethanesulfonyl)amide (TFSA−) with 1-methy-1-propoxyethylpyrrolidinium (Pyr1,2O3+), 1-methyl-1-ethoxypropylpyrrolidinium (Pyr1,3O2+), and 1-methyl-1-(methoxymethoxy)ethylpyrrolidinium (Pyr1,2O1O1+) was investigated using experimental and computational approach. Pyr1,2O3TFSA exhibited the lowest viscosity and highest ionic conductivity. Pyr1,2O1O1TFSA with two oxygen atoms in the side chain showed relatively high viscosity, indicating the physicochemical properties were affected sensitively by the position and number of ether oxygen atoms. Furthermore, by comparing with the structural isomers reported so far, we were able to systematically discuss the introduction effect of ether oxygen on the physicochemical properties of RTILs.

Gravity is explained here as a not moving phenomenon, that instead is emerging inside matter, since ether particles are assumed to be absorbed by matter (not colliding with matter). Therefore, no aberration in gravity. So, it was a great mistake to abolish Fatio's great idea [M. R. Edwards, Perspectives on Le Sage's theory of gravitation, (C Roy Keys, Montreal 2002)] due to the lack of aberration in gravity. This mistake is the reason to the fact that we do not understand gravity today. [ABSTRACT FROM AUTHOR]

Ever since Ether is launched as a digital currency, its rise has been rapid. It is currently the second most valuable digital currency in the world. There are more than 1 million transactions happening on the Ethereum network every day, and this number is expected to continue to increase. Due to the increasing number of transactions, fraudulent transactions have also increased, which has resulted in a large amount of money being lost and has also destroyed the livelihoods of many individuals. Due to their similarity to valid transactions, it is extremely difficult to distinguish between them. Additionally, Ethereum's pseudo‐anonymity adds to the difficulty of identifying the parties involved. Since there are millions of transactions every day, it would be difficult to manually verify each one. Therefore, a mechanism for validating these transactions is needed. In this context, this paper proposes a novel approach to detecting fraudulent accounts associated with these transactions by implementing machine learning algorithms among the given set of transactions. We propose a framework for creating a stacking classifier by combining several standalone classification algorithms and creating a meta‐learner based on the output of each base algorithm. The algorithms include Logistic Regression, Naive Bayes, Decision Trees, Random Forests, AdaBoosts, KNNs, SVMs, and Gradient Boosts. As a result of combining these algorithms, a powerful classifier with the ability to detect fraudulent transactions. A variety of machine learning models were trained and evaluated on the test set using various metrics. Based on the results of the individual algorithm the Random Forest algorithm achieved the highest accuracy of 95.47%, followed by Gradient Boosting at 94.61% which is an ensemble algorithm using the boosting technique. The Stacking classifier that combines Multinomial Naive Bayes and Random Forest as the base learners and logistic regression as the Meta learner achieved the highest accuracy of 97.18% with an F1 score of 97.02%. Based on the results of all the stacking models developed, it is concluded that algorithms tend to perform better when combined properly. When compared to the other approaches, the proposed approach has outperformed the others, making it feasible in the real world to detect fraudulent transactions. [ABSTRACT FROM AUTHOR]

The ether preparation experiment is important in organic chemistry experiments. "The preparation of methyl tert-butyl ether" and "The preparation of n-butyl ether" are the corresponding experiments in the textbook. Studying these ether preparation experiments is important for a comprehensive understanding of the chemical properties of alcohols and the SN1 and SN2 mechanisms of nucleophilic substitution reactions. However, there are still many issues in "The preparation of methyl tert-butyl ether" based on the SN1 mechanism in the textbook, such as the requirement of a stoichiometric amount of the sulfuric acid catalyst, difficult reaction monitoring, challenging purification of the product, and low yields. Herein, a non-flammable solid, diphenylmethanol, and ethanol were used as starting materials, and anhydrous ferric chloride was used as the catalyst to prepare the desired benzhydryl ethyl ether. After simple washing extractions, the desired benzhydryl ethyl ether product could be purified and obtained in 88%-90% yields and 95%-97% purities. Notably, the reaction mechanism of this experiment is the same as that of methyl tertbutyl ether preparation; however, the catalyst amount is significantly reduced, product separation and purification steps are greatly simplified, and product yield is significantly improved. This experiment is helpful for students to comprehensively understand basic theories, including the properties of carbocation intermediates, organic Lewis acidbase theories and their applications, and the SN1 mechanism. Further, it can cultivate students' appreciation of green chemistry principles. [ABSTRACT FROM AUTHOR]

The title compound, systematic name 4,4',6,6'-tetrachloro-2,2'-{[(2-methoxy-ethyl)azanediyl]bis(methylene)}diphenol (C17H17Cl4NO, 1), was prepared via a modified Mannich reaction between 2-meth-oxy-ethyl-amine, 2,4-dichlorophenol, and aqueous formaldehyde. The resulting amine bis(phenol) provides an interesting comparison to related species as a result of the electron-withdrawing substituents on the phenol rings, in combination with similar steric parameters. One of the Cl atoms was modeled as a two-component disorder with partial occupancies of 0.49 (3) and 0.51 (3), while the pendant ether group was modeled as a two-component disorder with partial occupancies of 0.867 (3) and 0.133 (3). A comparison of metrical parameters for the title compound and closely related structures provides insight into the use of these species as ligands to support transition-metal complexes for applications as homogeneous catalysts. [ABSTRACT FROM AUTHOR]

The unique properties of epoxy polymers have led to their wide application in various fields of modern technology. The influence of the structure of bisphenols on the properties of epoxy polymers, especially thermal ones, is known. However, the chemical structure of the hardener also influences the properties of epoxy polymers. As hardeners, we used acid hardeners of various structures. The following hardeners give high results in heat resistance: pyromellite and methyltetrahydrophthalic anhydrides. Polymers obtained by curing these components of diglycidal ethers of bisphenols with substituents of the norbornane type are deformed in the temperature range 220-245°C. The use of these hardeners gives high results in terms of heat resistance. These polymers formed by curing the aforementioned components decrease in mass by 10% in the temperature range of 340-400°C. [ABSTRACT FROM AUTHOR]

Different starch properties may cause alterations in the foodstuff's external appearance. However, modification processes in starches are usually secretive. The use of chemically modified starches is regulated by international standards, which makes it important to identify its presence and type. Mid-infrared spectroscopy (MIR)-modified starches' identification can be hindered by the presence of excess glucose. This research investigates types of modification in commercial starches and in approaches that circumvent MIR's limitations with exploratory analysis. It also considers that enzymatic hydrolysis (α-amylase and amyloglucosidase) can highlight the points of modification in the structure, which can be detected with infrared assays. To determine if sour cassava starch (FCS) is modified and check its type, six samples were selected: a native one, three of the most common cassava modified starches (etherified, esterified, and FCS), and two laboratory processed samples (Acid, Oxidized). The results showed that the sour cassava starch showed similarities with a commercial ester and an oxidized cassava starch, which may be due to the formation of a graft, corresponding to what the literature has already reported for corn starch treated with lactic acid and gamma radiation. [ABSTRACT FROM AUTHOR]

This study explores structure-reactivity relationships for the degradation of emerging perfluoroalkyl ether carboxylic acid (PFECA) pollutants with ultraviolet-generated hydrated electrons (eaq-). The rate and extent of PFECA degradation depend on both the branching extent and the chain length of oxygen-segregated fluoroalkyl moieties. Kinetic measurements, theoretical calculations, and transformation product analyses provide a comprehensive understanding of the PFECA degradation mechanisms and pathways. In comparison to traditional full-carbon-chain perfluorocarboxylic acids, the distinct degradation behavior of PFECAs is attributed to their ether structures. The ether oxygen atoms increase the bond dissociation energy of the C-F bonds on the adjacent -CF2- moieties. This impact reduces the formation of H/F-exchanged polyfluorinated products that are recalcitrant to reductive defluorination. Instead, the cleavage of ether C-O bonds generates unstable perfluoroalcohols and thus promotes deep defluorination of short fluoroalkyl moieties. In comparison to linear PFECAs, branched PFECAs have a higher tendency of H/F exchange on the tertiary carbon and thus lower percentages of defluorination. These findings provide mechanistic insights for an improved design and efficient degradation of fluorochemicals.

Chyle consists of lymph and emulsified fats absorbed from the intestine after digestion and absorption. Patients are often found of chyluria in endemic parts of Africa, India and southern Asia It is caused by the parasitic filarial nematode Wuchereria bancrofti (W. bancrofti). We often receive body fluids mixed with chyle eg. chyluria, chylothorax, chyloperitonium etc. in laboratory for confirmation. Well established biochemical method is there, but it demands expertise and time. To establish a simple method to confirm chyle in biological fluid .Equal volume of suspected chyle sample and ether are mixed by vigorous shaking and standing for 5 minutes, a white band appears at the junctions of two liquids. Sample taken from white band and observed under microscope. Round retractile globules can be seen. Utility of our method is that it does not demand too much of expertise, very short procedure and this method can be used in field where filariasis is endemic.

Practical application of a Si anode in a high-energy-density battery cannot be achieved due to the huge volume expansion of these anodes. Researchers have focused on binders of the anode to restrict volume expansion in order to address this issue, as the hydrogen bonds and mechanical properties of binders can be used to enhance adhesion and accommodate the volume changes of a Si anode. Herein, we comprehensively consider binders’ hydrogen bonds, mechanical properties, stability, and compatibility with the electrolyte solution, and design an ether-/ester-/fluorine-rich composite polymer, named P(TFEMA-co-IBVE). The proposed binder formula possesses outstanding stability, adhesion, and mechanical strength; moreover, it can accommodate the dramatic volume changes of a Si electrode and exhibits excellent electrochemical performance, achieving a high areal capacity of about 5.4 mA∙h∙cm−2. This novel polymer design may be applied to other electrode materials in the next generation of lithium-ion batteries.

The mechanism of Ethereum transactions analysis during the prevention and investigation of criminal offenses based on the study of modern experience in this area has been proposed. The directions of cryptocurrency use by offenders have been revealed. The relationship between the decrease of the cash market and the increase in the use of cryptocurrencies has been described. The state of legal regulation of cryptocurrencies in Ukraine has been studied. The insufficient regulation of the issue of handling cryptocurrencies in criminal proceedings has been emphasized. The issue of impossibility to seize cryptocurrency assets during criminal investigation has been raised. The problematic issues faced by law enforcement agencies in other countries when seizing cryptocurrencies have been outlined. The structure and peculiarities of the cryptocurrency Ethereum circulation have been revealed. The features of the Ethereum platform and its distinctive features have been studied. The key standards that characterize the work of the Ethereum platform have been analyzed, explanations of key terms have been provided. The essential data in the blockchain for analysis have been highlighted, the procedure for accessing the Ethereum blockchain transactions has been described. Various web resources which one can access the Ethereum transaction blockchain through have been provided. The purpose of email mixing, the conditions under which the anonymity of the email address is lost have been revealed. Some software tools used to analyze ethereum transactions have been evaluated by experiment. Automation of searching and building a schema of relations of different identifiers of e-transactions on the example of Maltego Community Edition and Crystal Expert have been demonstrated. Additional modules that need to be installed in Maltego Community Edition to analyze the relevant transactions effectively have been described. It has been emphasized that when analyzing ethereum transactions, it is necessary to use not only ready-made tools, but also various scientific methods, such as identifying key criminal groups and wallets, identifying cases of money laundering using cryptocurrencies, additional address profiling, prevention of illegal behavior on the trading ethereum platform. The importance of effective analysis of cryptocurrencies for investigation has been described. The effectiveness of the Crystal Blockchain platform as a tool for analyzing Ethereum transactions in criminal investigations has been evaluated. The technical side of law enforcement training on the seizure of cryptocurrency assets has been revealed. For this purpose, it is recommended to use the so-called test networks. The mechanism of controlled transfer of cryptocurrency assets for custodial and non-custodial wallets has been proposed.

The title compound, C17H18O3, crystallizes with three molecules in the asymmetric unit. The molecules differ in the conformation related to the ethoxy group and in the orientation of the two phenyl rings, one of which has the ethoxy group disordered over two positions with refined occupancies of 0.735:0.265 (9). In the crystal packing, the molecules are connected by weak C—H...π interactions.