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Synthesis and characterization of orthopalladated complexes containing tridentate c,N,O-oxazolones

POLYHEDRON 2022年 222卷

作者： Dalmau, David Jimenez, Ana I. Urriolabeitia, Esteban P. CSIC Univ Zaragoza Inst Sintesis Quim & Catalisis Homogenea ISQCH Pedro Cerbuna 12 Zaragoza 50009 Spain

The (Z)-4-aryliden-2-(2-acetoxyphenyl)-5(4H)oxazolones 1a-1c react with H2SO4 to give the corresponding (Z)4-aryliden-2-(2-hydroxyphenyl)-5(4H)oxazolones *** molecular structures of 1c and 2a have been determined by X-ray diffraction methods, and show planar skeletons. Oxazolones 2a-2c are potential c,N,Otridentate ligands towards transition metals, and their molecular design obeys to the search of a rigid environment around the metal. The reaction of Pd(OAc)2 with oxazolones 2a-2c (1:1 M ratio) in cF3cO2H or NcMe as solvents results in the synthesis of diverse complexes (3-7). As a function of the reaction conditions, two different bonding modes have been characterized: N,O-chelate in the dinuclear complexes [Pd(kappa 2-N,O-2b,c)(mu -O2ccF3)]2 (3b,c), as a result of the N-coordination and deprotonation of the hydroxy group;and c,N,Otridentate in mononuclear complexes [Pd(kappa 3-c,N,O-2a,b)(L)] (L = cF3cO2H 4a,b;dmso-d6 5a,b;NcMe 6b;pyridine 7b), obtained after N-bonding, OH deprotonation and c-H bond activation. All complexes have been fully characterized by HRMS and NMR methods, showing the high stability of the c,N,O-tridentate bonding mode.

关键词： Oxazolones c H bond activation Pd(II) complexes X-ray diffraction NMR spectroscopy

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Hot corrosion behavior of Nicr-cr3c2-caF2/BaF2 composite coating with NiAl bond coating in molten Nacl-Kcl and Nacl-Na2SO4 at 800?

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cORROSION ScIENcE 2022年 206卷

作者： Wang, J. H. Li, D. G. Shao, T. M. Tsinghua Univ Key Lab Tribol Beijing 100084 Peoples R China

The Nicr-cr3c2-caF2/BaF2 coating with the NiAl bond coating was sprayed on a Ni16cr13co4Mo(wt%) alloy by detonation-gun spray, and hot corrosion behaviors were studied by electrochemical measurements. In molten Nacl-Kcl, the corrosion products were mainly cr2O3. Gas phases such as cl2 led to spallations and cracks on the coating surface. In molten Nacl-Na2SO4, Na2SO4 decomposed and reacted with the coating. Mixed oxides formed a continuous corrosion layer, and Al diffused outward from bond coating to be oxidized. Some liquid phases existed in the corrosion layer and promoted hot corrosion. The detailed hot corrosion mechanisms in two molten salts were discussed.

关键词： A metal coatings B EIS EPMA polarization c hot corrosion

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Mg-HA-c/c composites Promote Osteogenic Differentiation and Repair Bone Defects Through Inhibiting miR-16

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FRONTIERS IN BIOENGINEERING AND BIOTEcHNOLOGY 2022年 10卷 838842页

作者： Qi, Hong Liu, Yang Wu, Lu Liu, chun Ni, Su Liu, Qizhan Ni, Xinye Sun, Qiang Nanjing Med Univ Sch Publ Hlth Ctr Global Hlth Key Lab Modern ToxicolMinist Educ Nanjing Peoples R China Nanjing Med Univ Nanjing Hosp 1 Dept Orthoped Nanjing Peoples R China Nanjing Med Univ Peoples Hosp Changzhou 2 Changzhou Jiangsu Peoples R China

The hydroxyapatite (HA) coating on carbon/carbon (c/c) is reasonable and feasible to obtain bone graft materials with appropriate mechanical and biological properties. However, improvement of the physical and chemical properties of HA-c/c composites to promote bone regeneration and healing remains a challenge. In our present study, the HA coatings on c/c with magnesium (Mg) (Mg-HA-c/c) composites were synthesized that ca (NO3)(2), Mg (NO3)(2), and NH4H2PO4 were mixed and coatings were made by electromagnetic induction deposition's heating. As determined with in vitro experiments, Mg-HA-c/c composites containing 10 and 20% Mg decreased miR-16 levels, increased cell viability, elevated the levels of osteogenesis-related genes, and promoted osteogenic differentiation of bone marrow mesenchymal stem cells (BMScs) seeded on their surfaces. In a rat model of skull defects, compared to the control group, at 4 and 12 weeks after the operation, the bone volume fraction (BV/TV) of Mg-HA-c/c composite group was increased by 8.439 +/- 2.681% and 23.837 +/- 7.845%, as well as the trabecular thickness (***) was 56.247 +/- 24.238 mu m and 114.911 +/- 34.015 mu m more. These composites also increased the levels of ALP and RUNX2 in skull. The Mg-HA-c/c composite-enhanced bone regeneration and healing were blocked by in situ injection of an miR-16 mimic lentivirus vector. Thus, Mg-HA-c/c composites promote osteogenic differentiation and repair bone defects through inhibiting miR-16.

关键词： miR-16 hydroxyapatite c c composite magnesium bone regeneration

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Investigating the Role of Gravity Waves on Equatorial Ionospheric Irregularities Using TIMED/SABER and c/NOFS Satellite Observations

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ATMOSPHERE 2022年第9期13卷

作者： Nigussie, Melessew Moldwin, Mark Yizengaw, Endawoke Bahir Dar Univ Sci Coll Phys Dept Washera Geospace & Radar Sci Res Lab POB 79 Bahir Dar Ethiopia Univ Michigan Dept Climate & Space Sci & Engn Ann Arbor MI 48108 USA Aerosp Corp Space Sci Applicat Lab El Segundo CA 90245 USA

In this paper, for the first time, simultaneous atmospheric temperature perturbation profiles obtained from the TIMED/SABER satellite and equatorial ion density and vertical plasma drift velocity observations with and without ESF activity obtained from the c/NOFS satellite are used to investigate the effect of gravity waves (GW) on ESF. The horizontal and vertical wavelengths of ionospheric oscillations and GWs are estimated by applying wavelet analysis techniques. In addition, vertically propagating GWs that dissipate energy in the ionosphere-thermosphere system are investigated using the spectral analysis technique. We find that the vertical wavelength of GW, corresponding to dominant wavelet power, ranges from 12 to 31 km regardless of the conditions of the ionosphere;however, GWs with vertical wavelengths between about 1 to 13 km are found every day, saturated between 90 and 110 km at different longitudinal sectors. Filtering out vertical wavelengths above 13 km from temperature perturbations, ranges of zonal wavelengths of GW (i.e., from about 290 to 950 km) are found corresponding to irregular and non-irregular ionosphere. Similarly, corresponding to dominant oscillations, the zonal wavelength of ion density perturbations is found within 16 to 1520 km. Moreover, we find an excellent agreement among the median zonal wavelengths of GW for the cases of irregular and non-irregular ionosphere and ion density perturbations that are 518, 495, and 491 km, respectively. The results imply that seed perturbations due to GW with a vertical wavelength from about 1 to 13 km evolve to ion density irregularity and may be amplified due to post-sunset vertical upward drift velocity.

关键词： gravity wave equatorial spread F c NOFS satellite SABER satellite

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The changing c/N of aggressive aniline: Metagenomic analysis of pollutant removal, metabolic pathways and functional genes

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cHEMOSPHERE 2022年第PT 1期309卷 136598页

作者： Zhang, Yunjie Zhang, Qian Peng, Haojin Zhang, Wenli Li, Meng Feng, Jiapeng He, Jing Su, Junhao Wuhan Univ Technol Sch Civil Engn & Architecture Wuhan 430070 Peoples R China

In order to optimize the degradation of high-concentration aniline wastewater, the operation of sequencing batch bioaugmentation reactors with different aniline concentrations (200 mg/L, 600 mg/L, 1000 mg/L) was studied. The results showed that the removal rates of aniline and cOD in the three reactors could reach 100%. When the aniline increased to 600 mg/L, the nitrogen removal efficiency reached the peak (51.85%). The increase of aniline inhibited the nitrification, while denitrification was enhanced due to the increase of c/N ratio. But this change was reversed by the toxicity of high concentrations of aniline. The metagenomic analysis showed that when the aniline concentration was 600 mg/L, the abundance distribution of microbial samples was more uniform. The improved of aniline concentration had led to the increase of aromatic compounds degradation metabolic pathways. In addition, the abundance of aniline degradation and nitrogen metabolism genes (dmpB, xylE, norB) was also promoted.

关键词： SBR Aniline concentration c N ratio Nitrogen metabolism Functional gene

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High temperature oxidation mechanisms of grain refined Fe-25Al-1.5Ta (+Tac/+(Ta,Nb)c) iron aluminides at 700 °c in air

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cORROSION ScIENcE 2022年 198卷

作者： Puetz, Rene Daniel Zander, Daniela Rhein Westfal TH Aachen Div Mat Sci & Engn Chair Corros & Corros Protect Intzestr 5 D-52072 Aachen Germany

The high temperature oxidation mechanisms of grain refined Fe-25Al-1.5Ta (at%) with Tac or (Ta,Nb)c additives were investigated at 700 ? in air for 503 h to study the influence of microstructural changes on the oxidation behaviour. While a thin and stable alpha-Al2O3 scale was formed at the Fe-Al matrix, additional phases were selectively oxidised leading to higher oxidation kinetics of Fe-25Al-1.5Ta with carbide additives. The selectively oxidised c14 (Fe,Al)2Ta Laves phase showed the formation of outer Fe2O3 and an inner (Al,Ta)-rich oxide, while Al-rich oxides were found along the (Al,Ta)-rich oxide/Fe-Al phase boundary and locally below Fe2O3.

关键词： A intermetallics (iron aluminides) B SEM B XRD c high temperature corrosion c internal oxidation c oxidation

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Simultaneous phosphorus and nitrogen removal with different c/N ratios in a low oxygen aeration system: Microorganisms and mechanisms

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WATER ENVIRONMENT RESEARcH 2022年第12期94卷 e10815页

作者： Jin, Baodan Liu, Ye Jia, Yusheng Niu, Jintao Wang, Lipei Qin, Hexian Wang, Ran Wang, Lan Ji, Jiantao Pang, Long Du, Jing Jing Zhengzhou Univ Light Ind Henan Collaborat Innovat Ctr Environm Pollut Contr Sch Mat & Chem Engn Zhengzhou Peoples R China Henan Hengan Environm Protect Technol Co Ltd Zhengzhou Peoples R China Henan Geol Bur Zhengzhou Peoples R China Zhengzhou Univ Coll Ecol & Environm Zhengzhou Peoples R China Zhengzhou Univ Light Ind Henan Collaborat Innovat Ctr Environm Pollut Contr Sch Mat & Chem Engn Zhengzhou 450001 Peoples R China

In this study, a combined system with simultaneous nitrification, denitrification, and phosphorus removal was operated in continuous low oxygen aeration mode, and the effect of lower oxygen aeration (dissolved oxygen [DO] 0.5-1.5 mg/L) on its performance was examined. The combined system consisted of sludge and high-efficiency biological packing and was operated using four carbon/nitrogen ratios (c/N) with being 10:1, 8:1, 6:1, 10:1. Experimental results showed that the combined system could perform an efficient nitrogen and phosphorus removal under low DO and c/N ratio of 8:1 condition, and removal efficiencies of chemical oxygen demand (cOD), NH4 (+)-N, and PO4 (3-)-P were 80.01%, 99.03%, and 89.51%, respectively. High-throughput analysis indicated that the functional species of denitrifying bacteria, including Ferruginibacter Azospira, comamonas, Bacilli, Hyphomicrobium, Thauera, and comamonadaceae, were important participants in biological nutrient removal. Meanwhile, Acinetobacter was enriched in the combined system, which contributed to phosphorus removal. Practitioner Points A combined system was operated firstly under continuous low oxygen condition. The lower dissolved oxygen (DO) of the combined system was maintained at 0.50-1.5 mg/L level. The combined system could realize simultaneous phosphorus and nitrogen removal under c/N ratio of 8:1. Several functional bacteria were enriched in the coupled systems.

关键词： c N combined system denitrification and phosphorous removal functional species low oxygen aeration

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Optimizing the interfacial potential distribution to mitigate high transient potential induced dissolution on c/Ti coated metal bipolar plates used in PEMFcs

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cORROSION ScIENcE 2022年 208卷

作者： Wang, Xian-Zong Zhang, Meng-Meng Hu, Qian Su, Shuo Fan, Hong-Qiang Wang, Haifeng Luo, Jing-Li Northwestern Polytech Univ State Key Lab Solidificat Proc Ctr Adv Lubricat & Seal Mat Xian 710072 Shaanxi Peoples R China Shanghai Univ State Key Lab Adv Special Steel Sch Mat Sci & Engn 99 Shangda Rd Shanghai 200444 Peoples R China Univ Alberta Dept Chem & Mat Engn Edmonton AB T6G 1H9 Canada Shenzhen Univ Coll Mat Sci & Engn Shenzhen 518060 Peoples R China

Developing a conductive and corrosion-resistant coating on metal bipolar plates is essential to mitigate the degradation induced by the high cathodic transient potentials of proton exchange membrane fuel cells. In this work, a multilayer nanoscale c/Ti coating is prepared on SS316L (c/Ti/SS). The c/Ti/SS achieves a highly prominent IcR of 1.59 m omega cm2 and corrosion rate of 2 x 10-8 A/cm2, remarkably better than the targets. Analysis of coating microstructure and composition suggests that the significantly enhanced corrosion resistance is attributed to the diffusional interfaces which optimize the potential distribution across the coating and improve the transpassive potential of c/Ti/SS.

关键词： c Ti coating cathodic transient potentials Interfacial contact resistance corrosion resistance Metal bipolar plates Proton exchange membrane fuel cells

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Innovative Nanocomposites for Low Power Phase-change Memory: GeTe/c Multilayers

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PHYSIcA STATUS SOLIDI-RAPID RESEARcH LETTERS 2022年第9期16卷

作者： Terebenec, Damien Bernier, Nicolas castellani, Niccolo Bernard, Mathieu Jager, Jean-Baptiste Tomelleri, Martina Paterson, Jessy cyrille, Marie-claire Tran, Nguyet-Phuong Giordano, Valentina M. Hippert, Francoise Noe, Pierre Univ Grenoble Alpes CEA Leti F-38000 Grenoble France Univ Grenoble Alpes CEA IRIG F-38000 Grenoble France Univ Lyon 1 CNRS UMR 5306 ILM F-69622 Villeurbanne France Univ Grenobles Alpes CNRS Grenoble INP LMGP F-38000 Grenoble France

Innovative nanocomposites consisting of [(GeTe)(4 nm/)c-1 nm](10) multilayers (MLs) deposited by magnetron sputtering are integrated in phase-change memory (PcM) test devices with a "wall structure." Scanning transmission electron microscopy (STEM) shows that an ML structure, with crystallized GeTe layers, is kept after integration in as-fabricated devices and also after an additional annealing of the devices at 425 degrees c. The programming current (RESET current) required to reach the high resistance state of [(GeTe)(4 nm)/c-1 nm](10) ML devices decreases by 45% after annealing at 425 degrees c. The reduction in RESET current is 55% and the reduction in drift coefficient is about 40% in ML devices annealed at 425 degrees c compared to similar devices incorporating Ge2Sb2Te5. STEM imaging, coupled with nano-beam electron diffraction and electron energy loss spectroscopy, of ML devices in the high resistance state shows that the RESET current reduction after annealing is correlated to a reduction of the amorphized volume.

关键词： c GeTe multilayers nanocomposites phase-change memory STEM

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Lithium Vacancy-Tuned [cuO4] Sites for Selective cO2 Electroreduction to c2+ Products

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SMALL 2022年第8期18卷 e2106433页

作者： Peng, chen Zhu, Xiaorong Xu, Zikai Yan, Shuai chang, Lo Yueh Wang, Zhiqiang Zhang, Junbo chen, Menghuan Sham, Tsun-Kong Li, Yafei Zheng, Gengfeng Fudan Univ Dept Chem Adv Mat Lab Shanghai 200438 Peoples R China Fudan Univ Fac Chem & Mat Sci Shanghai Key Lab Mol Catalysis & Innovat Mat Shanghai 200438 Peoples R China Nanjing Normal Univ Sch Chem & Mat Sci Jiangsu Collaborat Innovat Ctr Biomed Funct Mat Jiangsu Key Lab New Power Batteries Nanjing 210023 Peoples R China Soochow Univ Joint Int Res Lab Carbon Based Funct Mat & Devic Inst Funct Nano & Soft Mat FUNSOM Suzhou 215123 Jiangsu Peoples R China Univ Western Ontario Dept Chem 1151 Richmond St London ON N6A 5B7 Canada

Electrochemical cO2 reduction to valuable multi-carbon (c2+) products is attractive but with poor selectivity and activity due to the low-efficient c-c coupling. Herein, a lithium vacancy-tuned Li2cuO2 with square-planar [cuO4] layers is developed via an electrochemical delithiation strategy. Density functional theory calculations reveal that the lithium vacancies (V-Li) lead to a shorter distance between adjacent [cuO4] layers and reduce the coordination number of Li+ around each cu, featuring with a lower energy barrier for cO-cO coupling than pristine Li2cuO2 without V-Li. With the V-Li percentage of approximate to 1.6%, the Li2-xcuO2 catalyst exhibits a high Faradaic efficiency of 90.6 +/- 7.6% for c2+ at -0.85 V versus reversible hydrogen electrode without iR correction, and an outstanding partial current density of -706 +/- 32 mA cm(-2). This work suggests an attractive approach to create controllable alkali metal vacancy-tuned cu catalytic sites toward c2+ products in electrochemical cO2 reduction.

关键词： c (2+) products cO (2) reduction reaction electrochemical delithiation Li 2cuO (2) lithium vacancies

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