Engineering the Activity and Stability of the Zn-MOF Catalyst via the Interaction of Doped Zr with Zn.

Metallic atoms within metal-organic framework (MOF) materials exhibit a distinctive and adaptable coordination structure. The three-dimensional (3D) pore configuration of MOFs enables the complete exposure of metal active sites, rendering them prevalent in various catalytic reactions. In this study, zinc (Zn) atoms within Zn-based MOF materials, characterized by an abundance of valence electrons, are utilized for the transesterification of dimethyl carbonate (DMC). Additionally, the introduction of zirconium (Zr) effectively addresses the susceptibility of the MOFs' crystal structure to dissolution in organic solvents. The formulated catalyst, Zn-10%Zr-MOF(300), demonstrates remarkable catalytic performance with 91.5% DMC selectivity, 61.9% propylene carbonate (PC) conversion, and 56.6% DMC yield. Impressively, the catalyst maintains its high performance over five cycles. Results indicate that Zr interacts with Zn, forming new coordination bonds and enhancing the catalyst crystal structure stability. Moreover, electron transfer intensifies the alkalinity of the active Zn atoms, enhancing the overall catalyst performance. This research informs the development of transesterification heterogeneous catalysts and broadens the application scope of MOF catalysts.

Drymariamides A-J, Antiadipogenic Cyclopeptides Incorporating Noncanonical Amino Acids from Drymaria cordata.

Herein, we report an extensive phytochemical study on the whole plant of Drymaria cordata, which led to the isolation of ten new orbitides, named drymariamides A-J (1-10). Compounds 2, 3, and 5 incorporate rare residues of noncanonical amino acids of kynurenine (Kyn) or 3a-hydroxypyrroloindoline (HPI). Their structures with absolute configurations were elucidated by a combination of spectroscopic analysis, advanced Marfey's method, X-ray diffraction, and electronic circular dichroism analysis. Compounds 1-10 exhibited antiadipogenic effects in 3T3-L1 adipocytes, and the most potent compound 7 showed an EC50 value of 1.17 ± 0.19 µM.

Novel heterogeneous Fe-based catalysts for carbon dioxide hydrogenation to long chain α-olefins-A review.

The thermocatalytic conversion of carbon dioxide (CO2) into high value-added chemicals provides a strategy to address the environmental problems caused by excessive carbon emissions and the sustainable production of chemicals. Significant progress has been made in the CO2 hydrogenation to long chain α-olefins, but controlling C-O activation and C-C coupling remains a great challenge. This review focuses on the recent advances in catalyst design concepts for the synthesis of long chain α-olefins from CO2 hydrogenation. We have systematically summarized and analyzed the ingenious design of catalysts, reaction mechanisms, the interaction between active sites and supports, structure-activity relationship, influence of reaction process parameters on catalyst performance, and catalyst stability, as well as the regeneration methods. Meanwhile, the challenges in the development of the long chain α-olefins synthesis from CO2 hydrogenation are proposed, and the future development opportunities are prospected. The aim of this review is to provide a comprehensive perspective on long chain α-olefins synthesis from CO2 hydrogenation to inspire the invention of novel catalysts and accelerate the development of this process.

Aerococcus agrisoli sp. nov., isolated from paddy soil.

A non-spore-forming, Gram-stain-positive, short rod-shaped strain, designated SJQ22T, was isolated from a paddy soil sample collected in Shanghai, PR China. A comparative analysis of 16S rRNA gene sequences showed that strain SJQ22T fell within the genus Aerococcus, forming a clear cluster with the type strains of Aerococcus viridans (98.6 % sequence similarity) and Aerococcus urinaeequi (98.5 % sequence similarity). Strain SJQ22T grew at 30-45 °C (optimum, 30 °C), pH 6.0-8.0 (optimum, pH 7.0) and with a NaCl concentration of 0-4 % (optimum, 1 %). Cells were negative for oxidase and catalase activity. Chemotaxonomic analysis showed that strain SJQ22T possessed C16:0 and C18:1 ω9c as the predominant fatty acids. The DNA G + C content was 39.0 mol%. Strain SJQ22T exhibited DNA-DNA relatedness levels of 13±2 % with A. viridans ATCC 11563T and 9±2 % with A. urinaeequi IFO 12173T. Based on the data obtained, strain SJQ22T represents a novel species of the genus Aerococcus, for which the name Aerococcus agrisoli sp. nov. is proposed. The type strain is SJQ22T (=JCM 33111T=CCTCC AB 2018283T).

Dichapetalins from the Twigs of Dichapetalum longipetalum with Cytotoxic Activities.

Continued efforts to expand the structural diversity of dichapetalins and explore further the cytotoxic structure-activity relationships have led to the isolation of 17 undescribed analogues, dichapelonins A-Q (1-17), and three known compounds (18-20) from the twigs of Dichapetalum longipetalum. Compounds 1-17 comprise five compound classes as classified by varied C6-C2 conjugates at the A ring of the 13,30-cyclodammarane skeleton, and their structures were determined by spectroscopic data analysis, experimental electronic circular dichroism measurements, and X-ray crystallography. Biological tests revealed compounds 1-7 with a phenyl-butadiene appendage to be the most potent cytotoxic compound type of those evaluated.

H2O Derivatives Mediate CO Activation in Fischer-Tropsch Synthesis: A Review.

The process of Fischer-Tropsch synthesis is commonly described as a series of reactions in which CO and H2 are dissociated and adsorbed on the metals and then rearranged to produce hydrocarbons and H2O. However, CO dissociation adsorption is regarded as the initial stage of Fischer-Tropsch synthesis and an essential factor in the control of catalytic activity. Several pathways have been proposed to activate CO, namely direct CO dissociation, activation hydrogenation, and activation by insertion into growing chains. In addition, H2O is considered an important by-product of Fischer-Tropsch synthesis reactions and has been shown to play a key role in regulating the distribution of Fischer-Tropsch synthesis products. The presence of H2O may influence the reaction rate, the product distribution, and the deactivation rate. Focus on H2O molecules and H2O-derivatives (H*, OH* and O*) can assist CO activation hydrogenation on Fe- and Co-based catalysts. In this work, the intermediates (C*, O*, HCO*, COH*, COH*, CH*, etc.) and reaction pathways were analyzed, and the H2O and H2O derivatives (H*, OH* and O*) on Fe- and Co-based catalysts and their role in the Fischer-Tropsch synthesis reaction process were reviewed.

Synthesis of Liquid Hydrocarbon via Direct Hydrogenation of CO2 over FeCu-Based Bifunctional Catalyst Derived from Layered Double Hydroxides.

Here, we report a Na-promoted FeCu-based catalyst with excellent liquid hydrocarbon selectivity and catalytic activity. The physiochemical properties of the catalysts were comprehensively characterized by various characterization techniques. The characterization results indicate that the catalytic performance of the catalysts was closely related to the nature of the metal promoters. The Na-AlFeCu possessed the highest CO2 conversion due to enhanced CO2 adsorption of the catalysts by the introduction of Al species. The introduction of excess Mg promoter led to a strong methanation activity of the catalyst. Mn and Ga promoters exhibited high selectivity for light hydrocarbons due to their inhibition of iron carbides generation, resulting in a lack of chain growth capacity. The Na-ZnFeCu catalyst exhibited the optimal C5+ yield, owing to the fact that the Zn promoter improved the catalytic activity and liquid hydrocarbon selectivity by modulating the surface CO2 adsorption and carbide content. Carbon dioxide (CO2) hydrogenation to liquid fuel is considered a method for the utilization and conversion of CO2, whereas satisfactory activity and selectivity remains a challenge. This method provides a new idea for the catalytic hydrogenation of CO2 and from there the preparation of high-value-added products.

Carbon-Based Electron Buffer Layer on ZnOx -Fe5 C2 -Fe3 O4 Boosts Ethanol Synthesis from CO2 Hydrogenation.

The conversion of CO2 into ethanol with renewable H2 has attracted tremendous attention due to its integrated functions of carbon elimination and chemical synthesis, but remains challenging. The electronic properties of a catalyst are essential to determine the adsorption strength and configuration of the key intermediates, therefore altering the reaction network for targeted synthesis. Herein, we describe a catalytic system in which a carbon buffer layer is employed to tailor the electronic properties of the ternary ZnOx -Fe5 C2 -Fe3 O4 , in which the electron-transfer pathway (ZnOx →Fe species or carbon layer) ensures the appropriate adsorption strength of -CO* on the catalytic interface, facilitating C-C coupling between -CHx * and -CO* for ethanol synthesis. Benefiting from this unique electron-transfer buffering effect, an extremely high ethanol yield of 366.6 gEtOH kgcat -1 h-1 (with CO of 10 vol % co-feeding) is achieved from CO2 hydrogenation. This work provides a powerful electronic modulation strategy for catalyst design in terms of highly oriented synthesis.

Selective Conversion of Glycerol to Methanol over CaO-Modified HZSM-5 Zeolite.

Biodiesel is generally produced from vegetable oils and methanol, which also generates glycerol as byproduct. To improve the overall economic performance of the process, the selective formation of methanol from glycerol is important in biodiesel production. In the present study, a CaO modified HZSM-5 zeolite was prepared by an impregnation method and used for the conversion of glycerol to methanol. We found that the 10%CaO/HZSM-5 with Si/Al ratio of 38 exhibited highest selectivity to methanol of 70%, with a glycerol conversion of 100% under 340 ℃ and atmospheric pressure. The characterization results showed that the introduction of a small amount of CaO into the HZSM-5 did not affect the structure of zeolite. The incorporation of HZSM-5 as an acidic catalyst and CaO as a basic catalyst in a synergistic catalysis system led to higher conversion of glycerol and selectivity of methanol.

Aquabacterium soli sp. nov., a novel bacterium isolated from soil under the long-term application of bifenthrin.

Strain SJQ9T, an aerobic bacterium isolated from a soil sample collected in Shanghai, PR China, was characterized using a polyphasic approach. It grew optimally at pH 7.0, 30-35 °C and in the presence of 1 % (w/v) NaCl. A comparative analysis of 16S rRNA gene sequences showed that strain SJQ9T fell within the genus Aquabacterium. The closest phylogenetic relatives of strain SJQ9T were Aquabacterium citratiphilum DSM 11900T (98.6 % sequence similarity) and Aquabacterium commune DSM 11901T (96.4 %). Cells of the strain were Gram-stain-negative, motile, non-spore-forming, rod-shaped and positive for oxidase activity and negative for catalase. The chemotaxonomic properties of strain SJQ9T were consistent with those of the genus Aquabacterium: the major fatty acid was summed feature 3 (C16 : 1 ω6c and/or C16 : 1 ω7c). The isoprenoid quinone was Q-8. The major polar lipids were phosphatidylethanolamine, phosphatidylcholine, phosphatidylglycerol and diphosphatidylglycerol. The DNA G+C content was 65.7 mol%. Strain SH9T exhibited a DNA-DNA relatedness level of 34±2 % with A. citratiphilum DSM 11900T and 28±3 % with A. commune DSM 11901T. Based on the obtained data, strain SJQ9T represents a novel species of the genus Aquabacterium, for which the name Aquabacterium soli sp. nov. is proposed. The type strain is SJQ9T (=JCM 33106T=CCTCC AB 2018284T).

Facile Synthesis of Proton-Type ZSM-5 by Using Quasi-Solid-Phase (QSP) Method.

Herein, a simple and green quasi-solid-phase (QSP) method for facile synthesis of proton-type ZSM-5 avoiding use of excessive water, dry gel, Na+ cation and fluoride is reported. Crystallization by using the stoichiometric amount of TPAOH (tetrapropylammonium hydroxide) at 180 °C for only 12 h gave well-structured HZSM-5 crystals with high specific surface area of 429 m2 g-1 and high thermal stability. 5MRs was observed to closely relate the formation of MFI structure and QSP method exhibits shorter induction period (t0 ), higher nucleation rate (Vn ), and faster growth rate (Vg ). Moreover, HZ-12-180 showed extremely better and rather stable catalytic activity for methanol-to-propylene reaction by comparison with commercial HZSM-5.

Falsochrobactrum shanghaiense sp. nov., isolated from paddy soil and emended description of the genus Falsochrobactrum.

A non-spore-forming, motile, Gram-stain-negative, short rod-shaped strain, designated HN4T, was isolated from a paddy soil sample collected in Shanghai, China. A comparative analysis o-f 16S rRNA gene sequences showed that strain HN4T fell within the genus Falsochrobactrum, forming a clear cluster with the type strain of Falsochrobactrum ovis, with which it exhibited a 16S rRNA gene sequence similarity value of 98.2 %. Strain HN4T grew optimally at pH 7.0, 30-35 °C and in the presence of 1 % (w/v) NaCl. It was positive for oxidase activity. Chemotaxonomic analysis showed that strain HN4T contained ubiquinone-10 as the predominant respiratory quinone and possessed summed feature 8(C18 : 1ω7c and/or C18 : 1ω6c) and C19 : 0cyclo ω8c as predominant fatty acids. The major polar lipids were diphosphatidylglycerol, phosphatidylethanolamine, phosphatidylglycerol and phosphatidylcholine. The DNA G+C content was 56.9 mol%. Strain HN4T exhibited a DNA-DNA relatedness level of 18±1 % with Falsochrobactrum ovis CCM 8460T. Based on the data obtained in this study, strain HN4T represents a novel species of the genus Falsochrobactrum, for which the name Falsochrobactrumshanghaiense sp. nov. is proposed. The type strain is HN4T (=JCM 32785T=CCTCC AB 2018063T).

Structural Elucidation and Bioinspired Total Syntheses of Ascorbylated Diterpenoid Hongkonoids A-D.

Hongkonoids A-D (1-4), the first example of ascorbylated terpenoids featuring a unique 5,5,5-fused tricyclic spiroketal butyrolactone moiety and diterpenoid-derived long chain, were isolated from Dysoxylum hongkongense. Their structures were unambiguously assigned by a combination of spectroscopic data, chemical degradation, X-ray crystallography, CD analysis, and total synthesis. The total syntheses of compounds 1-4 were effectively accomplished by a convergent strategy with the longest linear sequences of 12-14 steps and overall yields of 5.4-9.6%. Notably, we exploited a bioinspired one-pot method to construct the key intermediate 14 from an easily made compound 12 by involving the cascade reactions of an elaborate Claisen rearrangement, deprotections, and a 5-exo-trig cyclization. The desired major epimer 14a was then transformed to the main building block 21. Assembly of 21 and the long chain vinyl iodide 7 was made by an NHK coupling reaction to furnish the framework of 1-4. Some of the hongkonoids and/or synthetic analogs showed significant to moderate inhibitory activities against NF-κB, 11ß-HSD1, and sterol synthesis. The most active NF-κB inhibitor 34 exhibited distinct inhibition on the LPS-induced inflammatory responses in RAW 246.7 and primary BMDM cells.

Alsobacter soli sp. nov., a novel bacterium isolated from paddy soil, emended description of the genus Alsobacter and description of the family Alsobacteraceae fam. nov.

Strain SH9T, an aerobic bacterium isolated from a paddy soil sample collected in Shanghai, China, was characterized using a polyphasic approach. It grew optimally at pH 7.0, temperatures of 30-35 °C and in the presence of 1 % (w/v) NaCl. Comparative analysis of 16S rRNA gene sequences showed that strain SH9T fell within the genus Alsobacter, forming a clear cluster with the type strain of Alsobacter metallidurans, with which it exhibited a 16S rRNA gene sequence similarity value of 98.5 %. Cells of strain SH9T were Gram-stain-negative, motile, non-spore-forming, rod-shaped, positive for catalase and oxidase activity, and negative for atmospheric nitrogen fixation and nitrate reduction. The strain was a chemo-organotrophic bacterium, incapable of growth on C1 substrates. The chemotaxonomic properties of strain SH9T were consistent with those of the genus Alsobacter: the predominant ubiquinone was Q-10, and the major fatty acid was summed feature 8 (C18 : 1ω7c and/or C18 : 1ω6c). The major polar lipids were diphosphatidylglycerol, phosphatidylethanolamine, phosphatidylglycerol, phosphatidylcholine and phosphatidylmonomethylethanolamine. The DNA G+C content was 68.5 mol%. Strain SH9T exhibited a DNA-DNA relatedness level of 20±2 % with A. metallidurans NBRC 107718T. Based on the data obtained, strain SH9T represents a novel species of the genus Alsobacter, for which the name Alsobactersoli sp. nov. is proposed. The type strain is SH9T (=JCM 32501T=CCTCC AB 2017284T). A new family, Alsobacteraceae fam. nov., is also proposed encompassing strain SH9T and Alsobacter metallidurans NBRC 107718T.

Dectin-2 polymorphism associated with pulmonary cryptococcosis in HIV-uninfected Chinese patients.

Dectin-2 is a C-type lectin receptor that can recognize critical structures of fungi and involve in the host immune response after pulmonary fungal infections. We aimed to investigate the association between Dectin-2 genetic polymorphisms and cryptococcosis among a series of human immunodeficiency virus (HIV)-uninfected Chinese patients. In this case control study, a total of 251 patients with cryptococcosis and 464 healthy controls were included. One tag-single nucleotide polymorphism (SNP) (rs11045418) located at 5'-flanking region of Dectin-2 gene was selected and genotyped in this study. Among 251 patients, there were 108 (43%) meningitis patients including 73 (67.7%) healthy ones, 74 (29.5%) pulmonary infected patients including 49 (66.2%) healthy ones, and 69 (27.5%) patients with both neural and pulmonary infection including 38 (55.1%) immunocompetent ones. One hundred and forty-three (74 plus 69) patients with pulmonary cryptococcosis and 177 (108 plus 69) patients with cryptococcal meningitis were compared with controls, respectively. Three samples from 143 pulmonary infected patients failed in genotyping. There was a significant difference between 86 immunocompetent pulmonary infected patients and controls in the overdominant model (C/T vs. T/T + C/C; OR, 0.59; 95%CI, 0.37-0.94; P, .026). Similar but not significant difference was found between the overall pulmonary infected patients and the controls in the overdominant model (OR, 0.77; 95%CI, 0.52-1.12; P, .17). No such difference was found between controls and patients with cryptococcal meningitis. Our study firstly showed a genetic association between Dectin-2 and pulmonary cryptococcosis.

Dealuminated Beta zeolite reverses Ostwald ripening for durable copper nanoparticle catalysts.

Copper nanoparticle-based catalysts have been extensively applied in industry, but the nanoparticles tend to sinter into larger ones in the chemical atmospheres, which is detrimental to catalyst performance. In this work, we used dealuminated Beta zeolite to support copper nanoparticles (Cu/Beta-deAl) and showed that these particles become smaller in methanol vapor at 200°C, decreasing from ~5.6 to ~2.4 nanometers in diameter, which is opposite to the general sintering phenomenon. A reverse ripening process was discovered, whereby migratable copper sites activated by methanol were trapped by silanol nests and the copper species in the nests acted as new nucleation sites for the formation of small nanoparticles. This feature reversed the general sintering channel, resulting in robust catalysts for dimethyl oxalate hydrogenation performed with supported copper nanoparticles for use in industry.

Cu/ZnV2O4 Heterojunction Interface Promoted Methanol and Ethanol Generation from CO2 and H2O under UV-Vis Light Irradiation.

Adopting the concurrent reduction of Cu2O during hydrothermal preparation of ZnV2O4, metal-semiconductor heterojunction Cu/ZnV2O4 nanorods were synthesized and applied to the catalytic generation of methanol and ethanol from CO2 aerated water under UV-vis light irradiation. 10Cu/ZnV2O4 obtained from 10 wt % composite amount of Cu2O exhibited a total carbon yield of 6.49 µmol·g-1·h-1. The yield of CH3OH and C2H5OH reached 3.30 and 0.86 µmol·g-1·h-1, respectively. 2.5Cu/ZnV2O4 displayed the highest ethanol yield of 1.58 µmol·g-1·h-1 due to the strong absorption in the visible light. Cu/ZnV2O4 was characterized using X-ray diffraction (XRD), scanning transmission electron microscopy (STEM), X-ray photoelectron spectroscopy (XPS), ultraviolet-visible (UV-vis) spectra, photoluminescence (PL) spectra, transient photocurrent response, and electrochemical impedance spectroscopy (EIS). Results showed that composite Cu0-ZnV2O4 increased the surface area and tuned the energy band position, which matches the reaction potential toward methanol and ethanol. The photocatalytic activity toward CH3OH and C2H5OH on Cu/ZnV2O4 is attributed to faster transmission and a slow recombination rate of photogenerated carriers at the heterojunction interface. Multielectron reactions for the production of CH3OH and C2H5OH are promoted. Free radical capture experiments indicated that the active species boost the reaction in the order of •OH > e- > h+.

Cu/PCN Metal-Semiconductor Heterojunction by Thermal Reduction for Photoreaction of CO2-Aerated H2O to CH3OH and C2H5OH.

g-C3N4-based materials show potential for photoreduction of CO2 to oxygenates but are subjected to fast recombination of photogenerated charge carriers. Here, a novel Cu-dispersive protonated g-C3N4 (PCN) metal-semiconductor (m-s) heterojunction from thermal reduction of a Cu2O/PCN precursor was prepared and characterized using in situ X-ray diffraction, scanning transmission electron microscopy, X-ray photoelectron spectroscopy, ultraviolet-visible (UV-vis) spectra, photoluminescence (PL) spectra, transient photocurrent response, and electrochemical impedance spectroscopy (EIS). The Cu amount in Cu/PCN and the reduction temperature affected the generation of CH3OH and C2H5OH from the photoreaction of CO2-aerated H2O. During calcination of Cu2O/PCN in N2 at 550 °C, Cu2O was completely reduced to Cu with even dispersion, and a m-s heterojunction was obtained. With thermal exfoliation, Cu/PCN showed a specific surface area and layer spacing larger than those of PCN. Cu/PCN-0.5 (12.8 wt % Cu) exhibited a total carbon yield of 25.0 µmol·g-1 under UV-vis irradiation for 4 h, higher than that of Cu2O/PCN (13.6 µmol·g-1) and PCN (6.0 µmol·g-1). The selectivity for CH3OH and C2H5OH was 51.42 and 46.14%, respectively. The PL spectra, transient photocurrent response, and EIS characterizations indicated that Cu/PCN heterojunction promotes the separation of electrons and holes and suppresses their recombination. The calculated conduction band position was more negative, which is conducive to the multielectron reactions for CH3OH and C2H5OH generation.

Three-dimensional porous structured germanium anode materials for high-performance lithium-ion full-cells.

Germanium (Ge) has a high specific capacity when used as an alloying anode in lithium-ion batteries. However, a large volume of expansion that occurs during charging and discharging hampers its practical applications. In order to improve the stability of the alloying anode, a three-dimensional (3D) germanium/carbon porous composite was produced. In situ X-ray diffraction and electrochemical dilatometry are used to study the alloying electrode's structural evolution during cycling, revealing that the carbon matrix and the linked porosity structure provide a high reversible lithiation and delithiation, resulting in limited electrode volume expansion and high stability. Moreover, combined with a high nickel content cathode, i.e., LiNi0.8Co0.1Mn0.1O2, the composite achieved a specific energy density of 396 W h kg-1 and stable cycling performance, which show potential for its application in lithium-ion full cells.

Ordered Nanopillar Arrays of Low Dynamic Noise Dry Bioelectrodes for Electrocardiogram Surface Monitoring.

Flexible bioelectric dry electrodes are an important part of long-term medical healthcare monitoring systems. In this study, a new method is proposed for the preparation of dry electrodes with micronanopillar arrays structured by designing dimensionally tunable anodized aluminum oxide (AAO) templates, by which polyaniline/thermoplastic polyurethane single-layer micronanopillar array structured dry electrodes (PANI/TPU-SE) and polyaniline/thermoplastic polyurethane double-layer micronanopillar array structured dry electrodes (PANI/TPU-DE) are prepared. Compared with the planar structure, the micronanopillar array structure can reduce the contact gap between the electrode and skin and increase the contact area, thus exhibiting lower contact impedance and higher signal quality. At 0.1 Hz, the impedances of the wet electrode, PANI/TPU-DE300, PANI/TPU-SE10, and planar structure electrodes are 269.5 kΩ, 375.5 kΩ, 398.1 kΩ, and 2.257 MΩ, respectively, and the impedance value for PANI/TPU-DE300 is smaller than that for PANI/TPU-SE10 and closer to that for the wet electrode. In addition, because the surface of the micronanostructure can conform to the human skin, about 210.7% increase in the peel strength of double-layer structure electrodes compared to flat structure electrodes, it shows a low baseline drift in the dynamic ECG measurement, and the signal-to-noise ratio in the walking state can reach 21.33 ± 5.4775 dB. Therefore, the prepared bioelectric dry electrode has a wide application prospect in the fields of wearable medical monitoring.