Basic Groups Research Articles

Preparation and Catalytic Properties of Gold Single-Atom and Cluster Catalysts Utilizing Nanoparticulate Mg-Al Layered Double Hydroxides.

Au single atoms and clusters were stabilized on Mg-Al layered double hydroxide nanoparticles (LDH NPs), and the obtained Au@LDH NPs were supported on SiO2 and CeO2. After hydrogen reduction, Au single atoms were found together with Au clusters on LDH/SiO2. In contrast to Au single-atom catalysts which are deposited in metal vacancies of oxide supports, the LDH NPs stabilize very small Au species despite the absence of metal vacancies. The obtained Au(0)@LDH/SiO2 catalyzed aerobic oxidation of alcohols, and Au single atoms maintained after the reaction. Given that only Au NPs were observed on bulk LDH, the abundant surface OH group of LDH NPs would contribute to stabilize Au, resulting in higher activity than Au/LDH-bulk. After calcination to transform LDH to mixed metal oxide (MMO), the obtained Au(0)@MMO/SiO2 also exhibited high catalytic activity. Moreover, Au(0)@LDH/CeO2 exhibited higher activity and excellent selectivity for hydrogenation of 4-nitrostyrene to 4-aminostyrene than conventional Au catalysts such as Au/CeO2 and Au/TiO2. We demonstrated that Au size can be minimized using LDH NPs, exhibiting high catalytic performance. The basic surface OH groups of LDH would be also beneficial for deprotonation of alcohols and heterolytic dissociation of H2 in the catalytic reactions.

Effects of different milk powders on the growth and intestinal flora in weaned rats: Comparison of special formula milk powder with ordinary milk powder

AbstractThe objective of this investigation was to examine the effects of distinct dosages of infant formula and diverse formula constituents on the growth and development of weaned rats. Fifty specific pathogen‐free (SPF) male Sprague–Dawley (SD) rats aged 3 weeks were divided into the basic diet group, 20% ordinary milk powder group, 20% special formula milk powder group, 30% ordinary milk powder group, and 30% special formula milk powder group randomly. After 28 days of feeding, compared with the basic diet group, the body mass and brain/body weight of rats in the 30% ordinary and special formula milk powder groups were decreased. At the Genus level, Bacteroides in the group supplemented with 20% special formula milk powder was significantly lower than that in the basic diet group, and Parabacteroides was significantly lower than that in the 20% ordinary milk powder group. Lactobacillus was significantly higher than those in the basic diet group and the 20% ordinary milk powder group, and Blautia was significantly higher than those in the basic diet group and the 20% and 30% ordinary milk powder groups, and UBA1819 was significantly higher than those in the other groups. The abundance of Parasutterella in the basic diet group was significantly higher than those in the groups supplemented with 20% ordinary milk powder, 20% special formula milk powder, and 30% ordinary milk powder. This study found that different doses and different formula components of infant milk powder could affect body mass and intestinal flora in Sprague–Dawley (SD) rats, and the addition of low‐dose (20%) special formula infant milk powder can increase the beneficial bacteria in the intestinal flora of rats and may reduce the pathogenic bacteria.

Simultaneous Modulation on Solvation Shell and Electrode Interface for Reversible Zinc Anode Realized by a Mutiplefunctional Additive

AbstractThe inferior reversibility of Zn metal anode caused by undesired Zn dendrite and severe interfacial side reactions has to be addressed for the commercial application of Zinc ion batteries (ZIBs). Here, a multiple functional sodium benzaldehyde 2,4‐disulfonate(B24DADS) additives with various blocks of polar sulfonate group, Lewis basic aldehyde groups, and hydrophobic benzene ring is proposed to regulate the solvation structure of Zn2+, construct an H2O‐poor and zincophilic dual electric layer structure, and create a passive SEI on the Zn anode surface, thus restaining dendrite growth and interfacial side reactions. Furthermore, uniform deposition mechanics of the Zn are revealed by the synergistic effect of induced deposition, additive‐derived SEI formation, and texture regulation. In addition, Na+ can also limit the growth of zinc dendrites based on electrostatic shielding mechanisms. Therefore, the multifunctional B24DADS additive grants the anode to deliver remarkable electrochemical performance. Under critical test conditions (20 mA cm−2/20 mAh cm−2), the zinc provides superior long cycling (3700 h) with a low polarization voltage (0.02 V). B24DADS containing electrolyte is well matched with manganese dioxide cathode. This effort renders a promising way to explore advanced additives with unique molecular structures for addressing zinc dendrite growth and rampant side effects.

Orderly Coating of Bilayer Polymer to Tailor Microenvironment for Efficient C−N Coupling Toward Highly Selective Urea Electrosynthesis

AbstractElectrosynthesis of urea from co‐reduction of carbon dioxide and nitrate is a promising alternative to the industrial process. However, the overwhelming existence of proton and nitrate as well as the insufficient supply of CO2 at the reaction interface usually result in complex product distributions from individual nitrate reduction or hydrogen evolution, instead of C−N coupling. In this work, we systematically optimize this microenvironment through orderly coating of bilayer polymer to specifically tackle the above challenges. Polymer of intrinsic microporosity is chosen as the upper polymer to achieve physical sieving, realizing low water diffusivity for suppressing hydrogen evolution and high gas permeability for smooth mass transfer of CO2 at the same time. Polyaniline with abundant basic amino groups is capable of triggering chemical interaction with acidic CO2 molecules, so that is used as the underlying polymer to serve as CO2 concentrator and facilitate the carbon source supply for C−N coupling. Within this tailored microenvironment, a maximum urea generation yield rate of 1671.6 μg h−1 mg−1 and a high Faradaic efficiency of 75.3 % are delivered once coupled with efficient electrocatalyst with neighboring active sites, which is among the most efficient system of urea electrosynthesis.

Highly efficient and selective synthesis of renewable isoprene over Mo-Fe-O and MgO/Mg(OH)2 composite catalysts.

Synthesis of renewable isoprene continues to attract significant interest, yet catalysts still need improvement for industrial applications. We report herein an efficient and novel Prins tandem approach for highly selective production of isoprene from bio-based methanol and isobutene over Mo-Fe-O and MgO/Mg(OH)2 acid-base bifunctional catalysts. Hydration decreases the number of strong basic sites O2- ions and increases OH groups over MgO, thus improving the isoprene selectivity. Basic OH on Mg(OH)2 promotes the Prins condensation of formaldehyde and isobutene, while acidic OH promotes dehydration of isoprenol to isoprene. Suitable contents and proportions of basic and acidic OH groups over Mg(OH)2 increase isoprene selectivity and methanol conversion to 90 and 92% on the Mo-Fe-O+Mg(OH)2 composite catalysts, respectively. It exhibits good recycling stability, with isoprene selectivity remaining 90% after five successive regenerations. DFT calculations reveal OH groups formed after hydration reduce the energy barrier of the H transfer step, thereby promoting the overall reaction.

SURGICAL STRATEGY OF TREATMENT OF PATIENTS WITH COMPLICATED LOCALLY ADVANCED STOMACH CANCER

Summary. Objective. Improvement of results of treatment of patients with complicated stomach cancer. Materials and methods. The analysis of the results of operative treatment of 418 patients with complicated locally expanded gastric cancer. The disease was complicated by bleeding in 252 (60.3%) patients, stenosis – in 89 (21.3%), perforation – in 15 (3.5%), their combination – in 62 (14.8%). Results. The common surgical tactics and operations were used at the group of control. The two-staged active-idividualized surgical tactic, that consist of closure by interrupted sutures at first stage and reconstructive operation at second, was used at the basic group. Radical surgery was performed in 168 (40.2%), in 250 (59.8%) – palliative and symptomatic. Postoperative complications arose to 82 patients (19.6%) and postoperative mortality to 7.2% (30 patients). Conclusion. There is the rational of using the two-staged surgical tactic. The implementation of the proposed surgical tactics and new operative interventions contributed to an increase in the number of radical operations from 62 (14.8%) in the comparison group to 106 (25.3%) in the main group and a decrease in postoperative mortality from 8.0% to 6.3%, respectively.

Non-hydrolytic sol-gel synthesis of amine-functionalized silica: Template- and catalyst-free preparation of mesoporous catalysts for CO2 valorization

Carbon dioxide utilization presents an important and topical research topic. However, the performance of catalysts needed for CO2 transformations does not achieve the necessary levels for their widespread application. To this end, we decided to study non-aqueous condensations providing amine-functionalized silica catalysts, possibly active in CO2-epoxide cycloaddition reaction. While non-hydrolytic sol-gel method is well-known for its efficiency in providing highly porous Lewis and Brønsted acid metallosilicates, here we show for the first time its application for the preparation of silica-based catalysts containing basic groups. First, the reaction conditions were screened to reproducibly obtain porous materials with preserved amine moieties. These were identified as follows: silicon tetraacetate and bridging tertiary amine silanes as precursors, toluene as a solvent, and temperature between 160 and 180 °C. In such a way, materials with up to 776 m2 g−1 and 1.58 cm3 g−1 were obtained in one-step process, without any template, after conventional drying step. Next, the amine-functionalized materials were tested in CO2-epoxide coupling providing cyclic organic carbonates with high selectivity (>99 %) and moderate activity (up to 86 % epichlorohydrin conversion after 1 h at 120 °C and 10 bar CO2). The characterization of spent catalysts revealed a presence of cyclic organic carbonates at the catalyst surface as well as conversion of tertiary amine groups to quaternary ammonium moieties.

Molecular recognition of halogen-bond of Diiodine with an Ambidentate ligand: Fluorometry as lead strategy for analysis in solution

Chemical connectivity of halogen bond (XB) of the diiodine with an ambidentate ligand of the N1-aryl-2-(trifluoromethyl)benzo[b][1,8]naphthyridin-4(1H)-one in solution and in solid state was presented. The organic ligand was characterized by featuring four basic moieties with different hardness (N-heteroarene, ketonic oxygen, methoxy oxygen and π-arene). The study in solution was performed through a simple steady state fluorescence measurements taking advantage on the use of a donor-acceptor (D-A) fluorophore having two key characteristics (i) presence of basic groups along the d-A chain and, (ii) a fluorescence dependent on an intramolecular charge-transfer (ICT) mechanism. It allowed us to distinguish unequivocally the binding preference of the ambidentate ligand toward the diiodine from the recognition of specific dye-fluorescence responses (ICT-quenching, ICT-enhancement, etc.). Fluorometric studies allowed us to elucidate that the diiodine interacts dominantly through the borderline function (N-heteroarene) of ligand under a wide range of diiodine concentration and discretely through the harder ketonic oxygen. UV–Vis spectroscopic confirmed the binding of the diiodine through N-arene moiety, giving typical association constants of 20–40 M-1 for the tested ambidentate ligands. Additionally, the fluorometry allowed us to verify the reversibility of the XB in solution through synchronized radioactivity- and absorption-fluorescence experiments based on nuclear and chemical decomposition of the diiodine, respectively, where the total recovery of the ICT-fluorescence, which was quenched under diiodine binding, confirmed the reversibility of the XB. Further studies in solid state (Raman spectroscopy) confirmed the binding preference of the diiodine toward the borderline N-arene. Experimental evidences of XB were supported and interpreted from DFT-calculations.

Food dye adsorption in single and ternary systems by the novel passion fruit peel biochar adsorbent

This study evaluated the passion fruit peel biochar (PFPB) as a novel adsorbent for synthetic food dyes indigotine blue (IB), tartrazine yellow (TY), and ponceau 4R (P4R) removal in single and ternary systems. A macroporous structure and a predominance of basic groups characterized PFPB. The pH study revealed better adsorption at pH 2.0. The response surface methodology optimization for adsorbent dosage and temperature predicted removal efficiencies of 100 % for IB, 79.8 % for TY, and 84.4 % for P4R. Elovich and Redlich-Peterson models better described kinetic and equilibrium, respectively, suggesting the contribution of chemical interactions. Thermodynamic data revealed endothermic, with an inordinate degree and spontaneous adsorption. In the ternary systems, antagonistic effects of interaction were noticed. The adsorption of synthetic effluents showed promising results with removal efficiencies of 99.6 % (IB), 60.2 % (TY), and 51.8 % (P4R). Therefore, we concluded that PFPB is a potential alternative low-cost synthetic food dye removal adsorbent.

Synthesis and structural characterization of acrylonitrile/vinyl imidazole copolymers and their amidoximated derivatives

Recently, environmental applications of copolymers such as CO2 capture and separation have become of significant interest. The development of copolymers with basic functional groups, such as amidoxime (AO) groups, represents a successful approach for enhancing absorption and separation of acidic molecules, such as CO2. In this research, acrylonitrile/N-vinyl imidazole (AN/VIM) copolymers were first synthesized through a free radical copolymerization method using 2,2′-azobisisobutyronitrile (AIBN) as the initiator and dimethylformamide as the solvent. The synthesized copolymers were then functionalized using hydroxylamine hydrochloride (NH2OH · HCl), the result being amidoximated (AO) copolymers. The synthesized copolymers were characterized by nuclear magnetic resonance (NMR) spectroscopy, thermogravimetric analysis and Fourier transform infrared spectroscopy. The analytical results simply confirmed that the copolymers and their amidoximated derivatives had successfully been synthesized. A microstructural study of amidoximated polymers using NMR spectroscopy clearly showed the tautomerization of AO groups.

Enhanced proton transfer in proton exchange membrane fuel cells via novel nanocomposite membrane incorporating (3-Mercaptopropyl)trimethoxysilane-graphene oxide and basic amino ligands: A synergistic acid-base approach

A nanocomposite polymer electrolyte membrane (MGC) was synthesized by blending MPTS (HS(CH2)3Si(OCH3)3) and graphene oxide (GO) nanosheets at varying weight ratios (91.5 to 9.5, respectively) for proton exchange membrane fuel cell (PEMFC) applications. By covalently modifying the GO support with MPTS through a silane modification process, the acidic MGC matrix is formed. The blending process, with ultrasonication and vigorous stirring, initiates two significant reactions in reactive MPTS: first, the conversion of methoxy groups (Si–OCH3) to silanols (Si-OH); second, the potential condensation of silanol groups to form siloxane bonds (Si–O–Si), followed by oxidation of sulfhydryl groups to sulfonic acid (-SO3H) groups by hydrogen peroxide. The resulting -SO3H groups connected to the siloxane network (Si-O-Si) adjacent to the GO. Two basic amino ligands – dopamine, and aminopropyl trimethoxysilane (APTES) were incorporated into the MGC matrix to establish acid-base pairs, promoting swift proton transport. These additions, at weight ratios of (0.5, 1, 2, and 7) wt%, synergistically contributed to the MGC matrix, forming effective proton channels. Various analytical techniques, including field emission-scanning electron microscopy (FE-SEM), atomic force microscopy (AFM), Raman spectroscopy, X-ray diffraction (XRD), and electrochemical impedance spectroscopy (EIS), were employed to assess the impact of functionalized basic amino groups on the MGC matrix. Notably, the MGC membrane containing 2 wt% of PDA as basic amino ligands exhibited optimal performance, showcasing an in-plane proton conductivity of 115.10 mS cm-1 under fully hydrated conditions at 90 °C, and the maximum power density (MPD) of 170.74 mW cm-2 with a current density of 1051.46 mA cm-2 at 60 °C and 100 % relative humidity (RH). In contrast, the MGC membrane, devoid of amino ligands, exhibited a comparatively low in-plane conductivity of 44.32 mS cm⁻¹ under identical conditions at 90 °C. Additionally, it recorded the MPD of 48.5 mW cm⁻², corresponding to a current density of 313.25 mA cm⁻² at 60 °C and 100 % RH. This study introduces an innovative approach for developing high-performance nanocomposite membranes for PEMs and related applications.

Gaining insights into the physicochemical properties and sequence space of blood–brain barrier penetrating peptides

The blood–brain barrier (BBB) poses a significant obstacle to the administration of drugs to the brain for the development of therapies of central nervous system (CNS) disorders. Blood-brain barrier penetrating peptides (BBBPps) are a group of peptides that can traverse the BBB by different processes without causing harm to the BBB. These peptides show promise as potential drugs for CNS ailments. Nevertheless, the process of identifying BBBPps using experimental approaches is both time-consuming and labour-intensive. To discover additional BBBPps as potential treatments for CNS diseases, it is critical to develop insilico methods that can distinguish BBBPps from non- BBBPps rapidly and precisely. In the current work, machine learning aided models are developed for accurate prediction of BBBPps using physicochemical and evolutionary information. The best model achieved an accuracy of 84.8 % by using 5-fold cross-validation and 79.8 % based on the holdout testing set on a reduced set of features. Further an extensive analysis is carried out for the black box models using model agnostic interpretation approaches to infer the physicochemical and sequence space of BBBPps. Basic amino acids and conservation of Arginine and Lysine are found to be more favoured in BBBPps. Further, basic amino acid property group and its interactions with other features are found to be prominent important interactions.

Clinical and laboratory peculiarities in postmenopausal patients with benign ovarian tumors

Objective. To assess clinical and laboratory peculiarities of postmenopausal patients with benign ovarian tumors. Materials and methods. The data of a prospective study of concomitant somatic and gynecological pathology in postmenopausal patients with benign ovarian tumors (basic group, n = 40) and patients without pathologies (comparison group, n = 15) are presented. Clinical and laboratory data were evaluated in both groups as well. Results. Postmenopausal patients with benign ovarian tumors were frequently exposed to myomas, chronic salpingitis and chronic cervicitis, when women with no ovarian neoplasms did not have these pathologies. Patients of the main group had higher levels of FSG, leptin, GBP and lower levels of vitamin D, than patients of the comparison group. Conclusions. Postmenopausal patients with benign ovarian tumors frequently have concomitant gynecological pathology, pronounced vitamin D insufficiency and high levels of FSG, leptin and GBP in serum samples.

Feasibility and Engagement of a Mobile App Preparation Program (Kwit) for Smoking Cessation in an Ecological Context: Quantitative Study.

Mobile health apps can facilitate access to effective treatment and therapeutic information services. However, the real-world effectiveness of mobile apps for smoking cessation and their potential impact in everyday settings remain unclear. In an ecological context, this study aimed to estimate the engagement rate of a mobile app-based smoking cessation preparation program and its potential impact on users' willingness, ability, and readiness to quit smoking. A total of 2331 "organic users" (ie, users who discover and install a mobile app on their own, without any prompts) chose 1 of 2 program versions of the mobile app (Kwit): the basic version or the premium version. Both versions were identical in design, with 4 more evidence-based content items and strategies in the premium version. Outcomes were analyzed based on automated data registered in the app (engagement rate, motivation to quit, motivation type, motivation levels, and satisfaction level). Mann-Whitney and χ2 tests were used to compare the results of both groups. As expected, in the ecological context, a high dropout rate was observed at different moments. A significant difference was observed between the 2 versions (n=2331; χ21=5.4; P=.02), with a proportionally higher engagement rate in the premium version (premium=4.7% vs basic=2%). Likewise, differences were also observed between the 2 groups in terms of reasons to quit (n=2331; χ24=19; P≤.001; V=0.08), motivation type (n=2331; χ27=14.7; P=.04), and motivation level. Users of the app's premium version more frequently reported "well-being" (23.3% vs 17.9%) and "planning a pregnancy" (7.4% vs 4.4%) as their primary reasons for quitting smoking compared to those with the basic version. Moreover, they reported being more likely to be driven in the smoking cessation process by intrinsic motivation (premium=28% vs basic=20.4%), as well as feeling significantly more willing (z score=156,055; P≤.001; Cohen d=0.15), able (z score=172,905; P=.04; Cohen d=0.09), and ready (z score=166,390; P=.005; Cohen d=0.12) to stop smoking than users who had the basic version before completion of the preparation program. Among participants who finished each version of the program (premium: 9/189, 4.8%; basic: 47/2142, 2.19%), significant improvements in motivation levels were observed in both groups, although in different areas for each group (willingness levels for the premium group and ability for the basic group). These results suggest that even in ecological contexts where engagement rates are meager, the Kwit preparation program can address ambivalence by increasing willingness to change, self-confidence, and readiness to quit among its users, especially those who feel less able to do so. Further development and evaluations are needed to better understand determinants for regular mobile health apps.

Exploring Digital Proficiency Among Mothers of School-going Children in Kerala

Early exposure to social and digital media in this digital age greatly influences children’s lives, leading to an increasing number of parents and educators becoming concerned about the potential negative effects of excessive screen time. By investigating mothers’ digital competencies as informal educators, this study fills a significant research gap. The paper emphasises women as mentors, highlighting their responsibility to supervise and guide their children’s use of digital devices in an era of pervasive connectedness. Using a modified version of the DigCompEdu framework, the study focuses on two essential elements: empowering children; and fostering their understanding of digital competence areas. A thousand homemakers from two wards of the Kochi Corporation area in the Ernakulam district, Kerala, India are included in the study. Discriminant analysis is used to identify four important skill areas that demonstrate significant group differences – between Novice, Basic, Independent, and Proficient user groups. Results imply that tailoring digital literacy programs to mothers’ varying proficiency levels can enhance their ability to navigate digital parenting effectively. Additionally, integrating sociodemographic factors into interventions can ensure relevance and efficacy in addressing digital competence disparities among mothers.

Mini-Worskhop: Artin Groups meet Triangulated Categories

Artin and Coxeter groups are naturally occurring generalisations of the braid and symmetric groups respectively. However, unlike for Coxeter groups, many basic group theoretic questions remain unanswered for general Artin groups – most notably the K(\pi,1) -conjecture for Artin groups remains open except for certain special families of Artin groups. Recently, Artin groups have also appeared as groups acting on triangulated categories, where the associated spaces of Bridgeland’s stability conditions provide new realisations of the corresponding K(\pi,1) spaces. The aim of the workshop is to bring together experts and early career researchers from two seemingly different areas of research: (i) geometric and combinatorial group theory and topology, and (ii) triangulated categories and stability conditions, to explore their intersection via the K(\pi,1) -conjecture.

Выбор рационального инструментария для анализа полифенолов цветков бессмертника песчаного и листьев артишока колючего в комплексе фармакологических исследований

Background: Pathology of the hepatobiliary system includes a heterogeneous group of diseases of the liver and biliary system caused by viral, bacterial and parasitic infections, neoplasms, toxic chemicals, including alcohol, nutritional errors, metabolic disorders and heart failure. One of the basic groups for pharmacological correction of this group of diseases is the use of hepatoprotectors, drugs that have a predominantly selective effect on the liver. The active ingredient of most plant hepatoprotectors are flavonoids and hydroxycinnamic acids. The most popular plants – hepatoprotectors containing these active substances include – artichoke prickly (Cynara scolymus (L.)) and sandy everlasting (Helichrysum arenarium (L.) Moench), a plant with choleretic action, also capable of hepatoprotective activity. The aim of the study: Development and comparative characterisation of methods for the analysis of polyphenolic composition of sandy everlasting flowers and artichoke leaves in complex pharmacological studies using HPLC and capillary electrophoresis methods. Materials and methods: The sum of polyphenolic compounds was subjected to chromatographic separation in gradient elution mode. Capillary electrophoresis was carried out in a variant of micellar electrokinetic chromatography (MEKC). The buffer solution used was a mixture of: borate buffer 20 mM (pH - 9.3) – beta-cyclodextrin 20 mM – ethyl alcohol (10:10:5). Results: The electrophoregrams of the separation of artichoke leaf extract by the MECC method showed the presence of 7 components belonging to oxycinnamic acids and flavonoids. The dominant ones are chlorogenic acid and luteolin7-glucoside. Similar results were obtained by the HPLC method. The electrophoregram of immortelle flower extract shows 9 components, of which the dominant one belongs to isosalipurposide. Chromatographic analysis of sandy everlasting flower extract showed the presence of the same components. Conclusion: The results of the analysis of the polyphenolic complex of artichoke leaves and sandy everlasting flowers by capillary electrophoresis agree with the data obtained by HPLC chromatography. This allows us to conclude that the MECC method allows the identification and quantification of each component in artichoke leaves and HPLC chromatography flowers along with HPLC. Moreover, the performance of the analysis by CE is more economically feasible than HPLC, since it does not require the use of solvents for the mobile phase and the availability of a set of columns.

The role of carbon textile surface functionalities in reactive adsorption of vapor and liquid 2-chloroethyl ethyl sulfide: Evaluating interactions at the interface

A carbon textile (CT) was chemically modified to increase its surface activity and promote the adsorption and degradation of 2-chloroethyl ethyl sulfide (CEES) - a surrogate for mustard gas. CT was initially subjected to oxidation (CTO), and then heated under ammonia (CTON) or hydrogen sulfide (CTOS) atmosphere to incorporate nitrogen or sulfur functionalities, respectively. Detoxification experiments were performed in closed vials using either vapor or liquid forms of CEES. The maximum vapor weight uptakes on CT, CTO, CTOS, and CTON were 399, 372, 434, and 489 mg/g, respectively. All textiles were able to prevent the vaporization of CEES liquid droplets. Although similar reaction products were detected in both vapor and liquid systems, the marked differences in the extent of CEES chemical transformation on the surfaces of the textiles indicate distinct detoxification pathways influenced by surface chemistry. Even though the heterogeneous surface of CTO, enriched with oxygen surface groups, facilitated various reactions, hydrolysis was the predominant pathway. The thermal treatment, regardless of the atmosphere, reduced the oxygen content, decreasing the extent of hydrolysis. However, incorporating basic surface groups such as pyridines, amines, or weak acids such as thiols promoted dehydrohalogenation as the main detoxification pathway on these samples.

Cobalt-Catalyzed Regio- and Enantioselective Hydroalkylation of 1,1-Disubstituted Styrenes

AbstractThe metal hydride catalyzed alkene hydroalkylation enables efficient alkyl–alkyl coupling, yielding structurally diverse chiral organic compounds. However, the control of stereochemical selectivity in alkene hydroalkylation still heavily relies on the assistance of substrate Lewis basic functional groups or polar heteroatom functional groups. We have recently developed a cobalt hydride catalytic system and established a paradigm of enantioselective control assisted by C–H···π noncovalent interactions. This approach enables the asymmetric hydroalkylation of 1,1-disubstituted styrenes, thereby circumventing the limitations imposed by substrate heteroatom functional groups.1 Introduction2 Reaction Development3 Synthetic Applications4 Mechanistic Investigation5 Conclusion and Future Outlook

Defect Engineering in a Nanoporous Thulium-Organic Framework in Catalyzing Knoevenagel Condensation and Chemical CO2 Fixation.

Defect engineering is an extremely effective strategy for modifying metal-organic frameworks (MOFs), which can break through the application limitations of traditional MOFs and enhance their functionality. Herein, we report a highly robust nanoporous thulium(III)-organic framework, {[Tm2(BDCP)(H2O)5](NO3)·3DMF·2H2O}n (NUC-105), with [Tm(COO)2(H2O)]n chains and [Tm2(COO)4(H2O)8] dinuclears as metal nodes and 2,6-bis(2,4-dicarboxylphenyl)-4-(4-carboxylphenyl)pyridine (BDCP) linkers. In NUC-105, each of the four chains of [Tm(COO)2]n and the two rows of [Tm2(COO)4(H2O)8] units is unified by the organic skeleton, resulting in a rectangular nanochannel with dimensions of 15.35 Å × 11.29 Å, which leads to a void volume of 50%. It is worth mentioning that the [Tm2(COO)4(H2O)8] cluster is very rare in terms of its higher level of associated water molecules, implying that the activated host framework can serve as a strong Lewis acid. NUC-105a exhibited great heterogeneous catalytic performance for CO2 cycloaddition with epoxides under the reaction conditions (0.60 mol % NUC-105a, 5.0 mol % n-Bu4NBr, 65 °C, 5 h), ensuring exclusive selectivity and high conversion rates. In addition, NUC-105a's strong catalytic impact on the Knoevenagel condensation of aldehydes and malononitrile can be attributed to the collaboration between the drastically unsaturated Lewis acidic Tm3+ centers and Lewis basic pyridine groups.