Extreme Gradient Boosting to Predict Atomic Layer Deposition for Platinum Nano-Film Coating.

Extreme gradient boosting (XGBoost) is an artificial intelligence algorithm capable of high accuracy and low inference time. The current study applies this XGBoost to the production of platinum nano-film coating through atomic layer deposition (ALD). In order to generate a database for model development, platinum is coated on α-Al2O3 using a rotary-type ALD equipment. The process is controlled by four parameters: process temperature, stop valve time, precursor pulse time, and reactant pulse time. A total of 625 samples according to different process conditions are obtained. The ALD coating index is used as the Al/Pt component ratio through ICP-AES analysis during postprocessing. The four process parameters serve as the input data and produces the Al/Pt component ratio as the output data. The postprocessed data set is randomly divided into 500 training samples and 125 test samples. XGBoost demonstrates 99.9% accuracy and a coefficient of determination of 0.99. The inference time is lower than that of random forest regression, in addition to a higher prediction safety than that of the light gradient boosting machine.

Heterogenized Phenanthroline-Pd(2+)-Catalyzed Alkoxycarbonylation of Aryl Iodides in Base-Free Conditions.

A phenanthroline-based porous organic polymer-supported heterogeneous Pd catalyst (Pd@Phen-POP) is facilely synthesized by the solvent knitting of a Phen scaffold via the Lewis-acid-catalyzed Friedel-Crafts reaction using dichloromethane as a source for linker in the presence of AlCl3. The catalyst very effectively catalyzes the alkoxycarbonylation of various substituted aryl iodides with various alcohols to give corresponding products in good to excellent yields. Owing to the heterotic nature of the catalyst, it can be easily separated by simple filtration from the reaction mixture and recycled.

Reductive Carbonylation of Nitroarenes Using a Heterogenized Phen-Pd Catalyst.

The reductive carbonylation of nitroarenes in the presence of MeOH and CO(g) is one of the interesting alternative routes without utilizing toxic phosgene and corrosive HCl generation for the synthesis of industrially useful carbamate compounds that serve as important intermediates for polyurethane production. Since homogeneous palladium catalysts supported by phen (phen = 1,10-phenanthroline) are known to be effective for this catalysis, the heterogenized Pd catalyst was developed using the phen-containing solid support. In this study, we report the synthesis of a phen-based heterogeneous Pd catalyst, Pd@phen-POP, which involves the solvent knitting of a phen scaffold via the Lewis-acid-catalyzed Friedel-Crafts reaction using dichloromethane as a source for linker in the presence of AlCl3 as a catalyst. The resulting solid material has been thoroughly characterized by various physical methods revealing high porosity and surface area. Similar to the homogeneous pallidum catalyst, this heterogeneous catalyst shows efficient reductive carbonylation of various nitroarenes. The catalytic reaction using nitrobenzene as a model compound presents a high turnover number (TON = 530) and a reasonable turnover frequency (TOF = 45 h-1), with a high selectivity (92%) for the carbamate formation. According to the recycling study, the heterogeneous catalyst is recyclable and retains ∼90% of the original reactivity in each cycle.

Efficient Nicotinamide Adenine Dinucleotide Regeneration with a Rhodium-Carbene Catalyst and Isolation of a Hydride Intermediate.

Regeneration of nicotinamide adenine dinucleotide (NADH) has been the primary interest in the field of enzymatic transformation, especially associating oxidoreductases given the stoichiometric consumption. The synthesized carbene-ligated rhodium complex [(η5-Cp*)Rh(MDI)Cl]+ [Cp* = pentamethylcyclopentadienyl; MDI = 1,1'-methylenebis(3,3'-dimethylimidazolium)] acts as an exceptional catalyst in the reduction of NAD+ to NADH with a turnover frequency of 1730 h-1, which is over twice that of the higher catalytic activity of the commercially available catalyst [Cp*Rh(bpy)Cl]+ (bpy = 2,2'-bipyridine). Offsetting the contentious atmosphere currently taking place over the specific intermediate of the NADH regeneration, this study presents pivotal evidence of a metal hydride intermediate with a bis(carbene) ligand: a stable form of the rhodium hydride intermediate, [(η5-Cp*)Rh(MDI)H]+, was isolated and fully characterized. This enables thorough insight into the possible mechanism and exact intermediate structure in the NAD+ reduction process.

Direct Heterogenization of the Ru-Macho Catalyst for the Chemoselective Hydrogenation of α,ß-Unsaturated Carbonyl Compounds.

In this study, a commercially available homogeneous pincer-type complex, Ru-Macho, was directly heterogenized via the Lewis acid-catalyzed Friedel-Crafts reaction using dichloromethane as the cross-linker to obtain a heterogeneous, pincer-type Ru porous organometallic polymer (Ru-Macho-POMP) with a high surface area. Notably, Ru-Macho-POMP was demonstrated to be an efficient heterogeneous catalyst for the chemoselective hydrogenation of α,ß-unsaturated carbonyl compounds to their corresponding allylic alcohols using cinnamaldehyde as a model compound. The Ru-Macho-POMP catalyst showed a high turnover frequency (TOF = 920 h-1) and a high turnover number (TON = 2750), with high chemoselectivity (99%) and recyclability during the selective hydrogenation of α,ß-unsaturated carbonyl compounds.

Algoriphagus aquimaris sp. nov., isolated from seashore sand.

Strain F21T, a marine, aerobic, Gram-negative, rod-shaped bacterium, was isolated from seashore sand sampled in Pohang, Republic of Korea. Cells of strain F21T were non-motile, catalase-positive, oxidase-positive, non-spore-forming and formed pinkish-red colonies on marine agar. The strain grew optimally at 37°C, pH 7 and in the presence of 2-3 % NaCl (w/v). Analysis of the 16S rRNA gene sequence of strain F21T revealed that it belonged to the genus Algoriphagus, family Cyclobacteriaceae, with similarity values of 98.1 and 96.8 % to Algoriphagus marincola DSM 16067T and Algoriphagus ornithinivorans IMSNU 14014T, respectively. When comparing the genome sequence of F21 T with those of the type strains of six species of the genus Algoriphagus, the values obtained were below the thresholds for analyses of average nucleotide identity (71.8-92.7 %) and in silico DNA-DNA hybridization using the Genome-to-Genome Distance Calculator (14.7-75.2 %). The DNA G+C content of strain F21T was 42.0 mol%. The chemotaxonomic characteristics of F21T included MK-7 as the predominant isoprenoid quinone, iso-C15 : 0, iso-C17 : 0 3-OH and summed feature 3 (C16 : 1ω6c and/or C16 : 1ω7c) as major cellular fatty acids, and phosphatidylcholine and phosphatidylethanolamine as major polar lipids. On the basis of phenotypic and chemotaxonomic properties, phylogenetic distinctiveness, and genomic data, we named strain F21T as Algoriphagus aquimaris sp. nov. and proposed that strain F21T (=KEMB 2250-007T= KCTC 72106T=JCM 33187T) in the genus Algoriphagus represents a novel species.

Direct Heterogenization of Salphen Coordination Complexes to Porous Organic Polymers: Catalysts for Ring-Expansion Carbonylation of Epoxides.

Salen and salphens are important ligands in coordination chemistry due to their ability to form various metal complexes that can be used for a variety of organic transformations. However, salen/salphen complexes are difficult to separate from the reaction mixture, thereby limiting their application to homogeneous systems. Accordingly, considerable effort has been spent to heterogenize the metallosalen/salphen complexes; however, this has resulted in compromised activities and selectivities. Direct heterogenization of metallosalens to form porous organic polymers (POPs) shows promise for heterogeneous catalysis, because it would allow easy separation while retaining catalytic function. Thus, a facile synthetic strategy for preparing metallosalen/salphen-based porous organic polymers through direct molecular knitting using a Friedel-Crafts reaction is presented herein for the first time. As representative candidates, salphenM(III)Cl (M = Al3+ and Cr3+) complexes are knitted by covalent cross-linking using this facile, scalable, one-pot method to synthesize highly POPs in high yields. When incorporated with [Co(CO)4]- anions, the resulting heterogeneous Lewis acidic metal (Al3+ and Cr3+) POPs exhibit propylene oxide ring-expansion carbonylation activity on par with those of their homogeneous counterparts.

Balancing between Heterogeneity and Reactivity in Porphyrin Chromium-Cobaltate Catalyzed Ring Expansion Carbonylation of Epoxide into ß-Lactone.

The synthesis of a unique heterogeneous catalyst that combines the functionality of a homogeneous catalyst and the advantages of a heterogeneous catalytic process is a continuing goal in various industrially applicable reactions. Here, we report heterogenization of homogeneous catalyst for lactone production from epoxide carbonylation through a facile polymerization using Friedel-Crafts reaction. A correlation between reactivity and degree of heterogeneity has been deduced by synthesizing different sized polymeric catalysts. The partially polymerized catalyst showed a remarkable initial turnover frequency of 400 h-1, and the fully polymerized catalyst displayed excellent selectivity during recycling with a total turnover number of 4100.

Hydrogenation of CO2 to Formate using a Simple, Recyclable, and Efficient Heterogeneous Catalyst.

Today, one of the most imperative targets to realize the conversions of CO2 in industry is the development of practically viable catalytic systems that demonstrate excellent activity, selectivity, and durability. Herein, a simple heterogeneous Ru(III) catalyst is prepared by immobilizing commercially available RuCl3· xH2O onto a bipyridine-functionalized covalent triazine framework, [bpy-CTF-RuCl3], for the first time. This novel catalyst efficiently hydrogenates CO2 into formate with an unprecedented turnover frequency (38800 h-1) and selectivity. In addition, the catalyst excellently maintains its efficiency over successive runs and produces a maximum final formate concentration of ∼2.1 M in just 2.5 h with a conversion of 12% in regard to CO2 feed. The apparent advantages of air stability, ease of handling, simplicity, the use of a readily available metal precursor, and the outstanding catalytic performance make [bpy-CTF-RuCl3] one of the possible candidates for realizing the large-scale production of formic acid/formate by CO2 hydrogenation.

Effect of Etching Time and Temperature on Plating Adhesion of Acrylonitrile Butadiene Styrene (ABS)-Based Material.

In this study, the effects of etching time and temperature on the adhesion of plated layers of acrylonitrile butadiene styrene (ABS) were investigated. The ABS surface micropores, which act as anchors to improve the adhesion of the plated layer, increased in numbers as the etching temperature increased. Adhesion was maximum at the etching time of 9 min at etching temperatures of 60 and 70 °C. For the etching times of 12 and 15 min, micropores on the ABS surface were incompletely filled during electroplating because the pores were both deep and narrow. The adhesion strength was decreased by these unfilled micropores, which further reduced the anchor effect. The ratio of the increased surface area ratio of the ABS to that of the plated surface was maximized at 9 min etching time, at which point the plating adhesion was also maximized.

Correlation between the Structure and Catalytic Activity of [Cp*Rh(Substituted Bipyridine)] Complexes for NADH Regeneration.

A series of water-soluble half-sandwich [Cp*RhIII(N^N)Cl]+ (Cp* = pentamethylcyclopentadiene, N^N-substituted 2,2'-bipyridine) complexes containing electron-donating substituents around the 2,2'-bipyridyl ligand were synthesized and fully characterized for the regioselective reduction of nicotinamide coenzyme (NAD+). The influence of the positional effect of the substituents on the structural, electrochemical, and catalytic properties of the catalyst was systematically studied in detail. The catalytic efficiency of the substituted bipyridine Cp*RhIII complexes are inversely correlated with their redox potentials. The 5,5'-substituted bipyridine Cp*RhIII complex, which had the lowest reduction potential, most effectively regenerated NADH with a turnover frequency of 1100 h-1. Detailed kinetic studies on the generation of intermediate(s) provide valuable mechanistic insight into this catalytic cycle and help to direct the future design strategy of corresponding catalysts.

Ionic-Liquid-Based Heterogeneous Covalent Triazine Framework Cobalt Catalyst for the Direct Synthesis of Methyl 3-Hydroxybutyrate from Propylene Oxide.

ß-Hydroxy esters are considered as potential building blocks for the production of fine chemicals and potential drug molecules in various industries. Developing an efficient and recyclable catalyst for the synthesis of ß-hydroxy esters is challenging. Here we report the first ionic-liquid-based heterogenized cobalt catalyst, [imidazolium-CTF][Co(CO)4], for the direct ring-opening carbonylation of propylene oxide to methyl 3-hydroxybutyrate (MHB) with 86% selectivity (>99% conversion).

Copolymerization of Epichlorohydrin and CO2 Using Zinc Glutarate: An Additional Application of ZnGA in Polycarbonate Synthesis.

The use of zinc glutarate (ZnGA) as a heterogeneous catalyst for the copolymerization of epichlorohydrin, an epoxide with an electron-withdrawing substituent, and CO2 is reported. This catalyst shows the highest selectivity (98%) for polycarbonate over the cyclic carbonate in epichlorohydrin/CO2 copolymerization under mild conditions. The (epichlorohydrin-co-CO2 ) polymer exhibits a high glass transition temperature (Tg ), 44 °C, which is the maximum Tg value obtained for the (epichlorohydrin-co-CO2 ) polymer to date.

Site-specific bioconjugation of an organometallic electron mediator to an enzyme with retained photocatalytic cofactor regenerating capacity and enzymatic activity.

Photosynthesis consists of a series of reactions catalyzed by redox enzymes to synthesize carbohydrates using solar energy. In order to take the advantage of solar energy, many researchers have investigated artificial photosynthesis systems mimicking the natural photosynthetic enzymatic redox reactions. These redox reactions usually require cofactors, which due to their high cost become a key issue when constructing an artificial photosynthesis system. Combining a photosensitizer and an Rh-based electron mediator (RhM) has been shown to photocatalytically regenerate cofactors. However, maintaining the high concentration of cofactors available for efficient enzymatic reactions requires a high concentration of the expensive RhM; making this process cost prohibitive. We hypothesized that conjugation of an electron mediator to a redox enzyme will reduce the amount of electron mediators necessary for efficient enzymatic reactions. This is due to photocatalytically regenerated NAD(P)H being readily available to a redox enzyme, when the local NAD(P)H concentration near the enzyme becomes higher. However, conventional random conjugation of RhM to a redox enzyme will likely lead to a substantial loss of cofactor regenerating capacity and enzymatic activity. In order to avoid this issue, we investigated whether bioconjugation of RhM to a permissive site of a redox enzyme retains cofactor regenerating capacity and enzymatic activity. As a model system, a RhM was conjugated to a redox enzyme, formate dehydrogenase obtained from Thiobacillus sp. KNK65MA (TsFDH). A RhM-containing azide group was site-specifically conjugated to p-azidophenylalanine introduced to a permissive site of TsFDH via a bioorthogonal strain-promoted azide-alkyne cycloaddition and an appropriate linker. The TsFDH-RhM conjugate exhibited retained cofactor regenerating capacity and enzymatic activity.

Exploring the Relationship between Fundamental Movement Skills and Health-Related Fitness among First and Second Graders in Korea: Implications for Healthy Childhood Development.

This study investigated the relationship between fundamental movement skills (FMSs) and health-related fitness (HRF) among first and second graders in South Korean elementary schools. It aimed to provide foundational data for developing physical education programs tailored to the motor development stages and fitness levels of younger elementary school students. This study utilized secondary data from the physical activity competence evaluation conducted by the Health Physical Activity Institute (HPAI). In October 2023, the HPAI evaluated the fundamental movement skills (jumping, running, hopping, static balance, dynamic balance, overhand throwing, and kicking) and health-related fitness (muscular strength, cardiorespiratory endurance, and flexibility) of 291 first and second-grade students. The collected data were analyzed through frequency and multiple regression analyses performed using SPSS software. The results revealed that higher scores in jumping and hopping are associated with greater muscular strength, cardiorespiratory endurance, and flexibility. Running had no significant effect on HRF elements. Higher scores in static balance (i.e., that used in single-leg stance) were associated with increased muscular strength, cardiorespiratory endurance, and flexibility, but dynamic balance (balance beam walking) did not have a significant effect. Higher scores in overhand throwing were associated with greater muscular strength and cardiorespiratory endurance, but kicking did not show a significant association. Overall, these findings emphasize the importance of prioritizing jumping and static balance in physical education for the well-rounded health development of first and second graders. Based on the results derived from this study, it is expected to serve as a theoretical basis for including "jumping" and "static balance" in the first and second grade curriculum of elementary schools, thereby providing essential guidance.

Bis(4-amino-pyridine){2,2'-[1,2-phenyl-enebis(nitrilo-methanylyl-idene)]diphen-ol-ato}cobalt(III) nitrate.

In the title compound, [Co(C20H14N2O2)(C5H6N2)2]NO3, the Co(III) atom is coordinated in a slightly elongated octa-hedral geometry by the N2O2 donor set of the tetra-dentate Schiff base ligand and by the pyridine N atoms of two trans-arranged monodentate 4-amino-pyridine mol-ecules. The pyridine rings are aligned nearly perpendicularly to each other [dihedral angle = 82.28 (13)°]. The phen-oxy rings form dihedral angles of 12.37 (12) and 12.16 (14)° with the phenyl-ene ring. In the crystal, N-H⋯O and C-H⋯O hydrogen bonds link the ions into a three-dimensional network.

Bis(4,4''-difluoro-1,1':3',1''-terphenyl-2'-carboxyl-ato-κO)tetra-kis-(methanol-κO)calcium methanol tetra-solvate.

In the title compound, [Ca(C(19)H(11)F(2)O(2))(2)(CH(3)OH)(4)]·4CH(3)OH, the Ca(2+) ion is located on an inversion centre and is hexa-coordinated by two O atoms of two 4,4''-difluoro-1,1':3',1''-terphenyl-2'-carboxyl-ate ligands and four O atoms of four methanol ligands, forming a CaO(6) polyhedron with a slightly distorted octa-hedral coordination geometry. The Ca-O-C angle between the carboxyl-ate group and the calcium ion is 171.8 (2)°. Two types of inter-molecular hydrogen-bond inter-actions (C=O⋯H and O-H⋯O) between the carboxyl-ate ligand, the methanol solvent mol-ecules and the coordinating methanol ligands generate a two-dimensional network parallel to (001).

Living ring-opening polymerization of ß-butyrolactone initiated by mononuclear zirconium compounds containing sterically hindered N,O-chelate and anionic dimethylamide ligands.

The ring-opening polymerization of ß-lactones into polyhydroxyalkanoates (PHA), biodegradable polymers with high molecular weight and narrow polydispersity, is of significant interest. The mononuclear zirconium compound containing sterically hindered N,O-chelate and anionic dimethylamide ligands was used as an initiator for the polymerization of ß-butyrolactone (BBL), resulting in polyhydroxylbutyrate (PHB) with a number-average molecular weight of 12 000 g mol-1. Kinetic studies demonstrate a first-order dependence on ß-butyrolactone (BBL) concentration at room temperature, accompanied by narrow molecular weight distributions (ca. 1.03-1.07), indicating a well-controlled living polymerization.

Silver nanoparticles are assembled only on the two facets of the rod template.

Although the focus of nano-research appears to be shifting to the creation of the secondary structures using primary nanoparticle (NP) building blocks, very complex preparation routes to assemble NPs have been reported so far. In this work, for the first time, we demonstrate that silver NPs can be organized to assemble on the two facets of the 1-dimensional rod template via facile one-step process. This method could potentially be used to prepare assembly of diverse metal, semiconductor, or metal oxide NPs in the one dimensional material form.

Dichloridobis(2-phenyl-pyridine-κN)zinc(II).

In the title compound, [ZnCl(2)(C(11)H(9)N)(2)], the Zn(2+) cation lies on a twofold axis and is coordinated by two Cl(-) anions and the N atoms of two 2-phenyl-pyridine ligands, forming a ZnN(2)Cl(2) polyhedron with a slightly distorted tetra-hedral coordination geometry. The dihedral angle between the phenyl ring and the metal-bound pyridine ring is 50.3 (4)° for each 2-phenyl-pyridine ligand. This arranges the phenyl ring from one ligand in the complex above the pyridine ring of the other resulting in an intra-molecular π-π inter-action, with a centroid-centroid distance of 3.6796 (17) Å. Weak C-H⋯Cl hydrogen bonds stabilize the crystal packing, linking mol-ecules into chains along the c axis.