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Selective N-Monomethylation of Anilines with Methanol catalyzed by commercial Pd/c as an Efficient and Reusable catalyst

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ASIAN JOURNAL OF ORGANIc cHEMISTRY 2019年第11期8卷 2046-2049页

作者： Jiang, Lei Guo, Fang Wang, Yinran Jiang, Jialin Duan, Yangzhi Hou, Zhaomin Dalian Univ Technol Sch Chem Engn Dept Polymer Sci & Engn State Key Lab Fine Chem Dalian 116012 Peoples R China RIKEN Organometall Chem Lab 2-1 Hirosawa Wako Saitama 3510198 Japan RIKEN Ctr Sustainable Resource Sci 2-1 Hirosawa Wako Saitama 3510198 Japan

N-methylation of amines is one of the most important c-N bond-forming reactions and is widely utilized for the synthesis of numerous agrochemicals, drugs, natural products, and dyes. In this paper, the N-monomethylation of aniline derivatives using Pd/c catalyst and methanol as the methylation reagent was investigated. The N-monomethylation of various anilines was achieved with high activity and selectivity under relatively mild reaction conditions, and the yield of N-monomethyl anilines was over 90 %. Notably, the commercial, readily available, and inexpensive heterogeneous catalyst, Pd/c, could be easily recovered and reused more than five times with only a slight decrease in activity;gram-scale experiments were also successfully performed.

关键词： Pd c selective N-methylation methanol

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Double Heterozygosity for Hb Durham-Nc (HBB: c.344T>c) [β114(G16)Leu→Pro] and the IVS-I-110 (HBB: c.93-21G>A) causing a Severe β-Thalassemia Phenotype

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HEMOGLOBIN 2019年第3期43卷 210-213页

作者： cannata, Monica cassara, Filippo Vinciguerra, Margherita Licari, Paola Passarello, cristina Leto, Filippo Lo Pinto, carmen Pitrolo, Lorella Ganci, Riccardo Maggio, Aurelio Giambona, Antonino Villa Sofia Cervello Hosp Lab Mol Diag Rare Dis Dept Hematol Rare Dis Blood & Blood Forming Organ Via Trabucco 180 I-90146 Palermo Italy Villa Sofia Cervello Hosp Dept Pediat Palermo Italy

The evaluation of a 10-month-old girl of Sicilian origin with a clinical phenotype of severe thalassemia led to the identification of two beta-globin gene defects, a beta-thalassemia (beta-thal), mutation at IVS-I-110 (HBB: c.93-21G>A) and a variant hemoglobin (Hb) mutation at codon 114 (HBB: c.344T>c) on the other allele, reported as Hb Durham-N.c. (also known as Hb Brescia) [beta 114(G16)Leu -> Pro] in the HbVar database. A very low Hb level (Hb 3.5 g/dL), microcytosis [mean corpuscular volume (McV) 63.2 fL] and hypocromia [mean corpuscular Hb (McH) 19.6 pg], increased red blood cell (RBc) distribution width (RDW) (36.0%), higher reticulocytes (6.2%), anisocytosis, poikilocytosis, hypocromia, basophilic stippling and inclusion body formation, were present in the affected subject. Analysis of other family components showed the presence of HBB: c.93-21G>A defect in the mother and in her brother, while Hb Durham-N.c. was absent in all other relatives, thus, this mutation has arisen as a de novo defect. This is the first case described as a severe thalassemic phenotype in a compound heterozygote carrier of this unstable Hb and a common beta-thalassemic allele. The important information gained from this case is that a rare dominant or recessive mutation may arise in every individual, even if this is a very rare event.

关键词： Autosomal dominant HBB mutation hemoglobin (Hb) Hb Durham-N c de novo HBB mutation unstable hemoglobin (Hb)

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New Electrochemical Approach for the Synthesis of Pd-PdO/c Electrocatalyst and Application to Formic Acid Electrooxidation

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cHEMISTRYSELEcT 2019年第29期4卷 8390-8393页

作者： Kuriganova, Alexandra B. Faddeev, Nikita A. Leontyev, Igor N. Allix, Mathieu Rakhmatullin, Aydar Smirnova, Nina, V Platov South Russian State Polytech Univ NPI Prosvescheniya Str 132 Novocherkassk 346428 Russia Southern Fed Univ Zorge Str 5 Rostov Na Donu 344090 Russia Univ Orleans CEMHTI UPR3079 CNRS F-45071 Orleans France

Pd-PdO/c catalyst for formic acid electrooxidation has been synthesized via electrochemical dispersion of Pd foil electrodes under pulse alternating current conditions in Nacl aqueous electrolyte. About 35 wt% of the as-prepared Pd-PdO/c specimen is PdO as revealed by X-ray diffraction. The microstructural characteristics and catalytic activity of the synthesized Pd/c catalyst have been compared with those of a Pt/c catalyst prepared under the same conditions. Pd nanoparticles of Pd-PdO/c catalyst exhibit smaller average dimensions and narrower particle size distribution - 7.4 +/- 0.5 nm and 1.9 +/- 0.5 respectively for Pd and PdO particles. The process of ethanol electrooxidation on the catalyst was characterized by high overvoltage (up to 800 mV). The overvoltage of the formic acid electrochemical oxidation on Pd/c is 590 mV less than on Pt/c.

关键词： Pd c alternating current electrochemical dispersion formic acid fuel cell

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Research on Material Removal Mechanism of c/Sic composites in Ultrasound Vibration-Assisted Grinding

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MATERIALS 2020年第8期13卷 1918页

作者： Wang, Dongpo Lu, Shouxiang Xu, Dong Zhang, Yuanlin Beihang Univ Sch Mech Engn & Automat Beijing 100191 Peoples R China Dalian Univ Technol Minist Educ Key Lab Precis & Nontradit Machining Technol Dalian 116024 Peoples R China Beihang Univ Sch Automat Sci & Elect Engn Beijing 100191 Peoples R China

c/Sic composites are the preferred materials for hot-end structures and other important components of aerospace vehicles. It is important to reveal the material removal mechanism of ultrasound vibration-assisted grinding for realizing low damage and high efficiency processing of c/Sic composites. In this paper, a single abrasive particle ultrasound vibration cutting test was carried out. The failure modes of Sic matrix and carbon fiber under ordinary cutting and ultrasound cutting conditions were observed and analyzed. With the help of ultrasonic energy, compared with ordinary cutting, under the conditions of ultrasonic vibration-assisted grinding, the grinding force is reduced to varying degrees, and the maximum reduction ratio reaches about 60%, which means that ultrasonic vibration is beneficial to reduce the grinding force. With the observation of cutting debris, it is found that the size of debris is not much affected by the cs>apcs> with ultrasound vibration. Thus, the ultrasound vibration-assisted grinding method is an effective method to achieve low damage and high efficiency processing of c/Sic composites.

关键词： c Sic composites ultrasound vibration material removal mechanism

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core-Shell FeSe2/c Nanostructures Embedded in a carbon Framework as a Free Standing Anode for a Sodium Ion Battery

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SMALL 2020年第47期16卷 e2002200-e2002200页

作者： Yousaf, Muhammad Wang, Zhipeng Wang, Yunsong chen, Yijun Ali, Usman Maqbool, Muhammad Imran, Ali Mahmood, Nasir Gao, Peng Han, Ray P. S. Peking Univ Int Ctr Quantum Mat & Electron Microscopy Lab Sch Phys Beijing 100871 Peoples R China Peking Univ Dept Mat Sci & Engn Beijing 100871 Peoples R China Peking Univ Sch Phys Artificial Micro & Mesoscop Phys Beijing 100871 Peoples R China RMIT Univ Sch Engn 124 La Trobe St Melbourne Vic 3001 Australia Jiangxi Univ Tradit Chinese Med Canc Res Ctr Nanchang 330004 Jiangxi Peoples R China

Embedding the functional nanostructures into a lightweight nanocarbon framework is very promising for developing high performance advanced electrodes for rechargeable batteries. Here, to realize workable capacity, core-shell (FeSe2/c) nanostructures are embedded into carbon nanotube (cNT) framework via a facile wet-chemistry approach accompanied by thermally induced selenization. The cNT framework offers 3D continuous routes for electronic/ionic transfer, while macropores provide adequate space for high mass loading of FeSe2/c. However, the carbon shell not only creates a solid electronic link among cNTs and FeSe2 but also improves the diffusivity of sodium ions into FeSe2, as well as acts as a buffer cushion to accommodate the volume variations. These unique structural features of cNT/FeSe2/c make it an excellent host for sodium storage with a capacity retention of 546 mAh g(-1) even after 100 cycles at 100 mA g(-1). Moreover, areal and volumetric capacities of 5.06 mAh cm(-2) and 158 mAh cm(-3) are also achieved at high mass loading 16.9 mg cm(-2), respectively. The high performance of multi-benefited engineered structure makes it a potential candidate for secondary ion batteries, while its easy synthesis makes it extendable to further complex structures with other morphologies (such as nanorods, nanowires, etc.) to meet the high energy demands.

关键词： cNT FeSe2 c double cage protection system free standing electrode high areal capacity sodium ion battery

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Preparation and characterization of N-doped TiO2/c composite

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MATERIALS RESEARcH EXPRESS 2020年第6期7卷

作者： Leng, Senlin Ran, Yaozong Yang, Yingchang Tongren Univ Sch Mat & Chem Engn Res Ctr Mat & Chem Engn Tongren 554300 Peoples R China

In this work, the N-doped TiO2/c composite is successfully prepared using electrospinning technique. TEM, XPS and Raman techniques are used to characterize the morphologies and microstructure of the as-fabricated composite, confirming that the incorporation of N into TiO2/c can not only reduce the d-spacing of TiO2 nanocrystals, but also can transform it into another TiO2 crystal form. Furthermore, amorphous carbon in this composite can be transferred to graphite under the effect of TiO2 during calcination processes. The N-doped TiO2/c sample with variable pore sizes exhibit the largest specific surface area, and the crystal forms of TiO2 are close related to the value of specific surface area and the pore sizes.

关键词： TiO2 c N-doped TEM Raman

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Russian doll architecture enables a high-rate and long-life Mnco2O4/c-lithium battery

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NANOTEcHNOLOGY 2020年第37期31卷 375404-375404页

作者： Hou, Li Deng, Shuolei Jiang, Yang cui, Ruiwen Zhou, Yanyan Guo, Yuanyuan Li, Jinghong Gao, Faming Yanshan Univ Key Lab Appl Chem Qinhuangdao 066004 Hebei Peoples R China

Realizing high capacity at high current densities is one of the challenges for battery electrode materials towards practical applications, especially for metal oxide electrode materials. Designing a specific structure that can alleviate volume expansion and accelerate the diffusion of the ions is an effective way to achieve this goal. Herein, a porous multilayer core-shell structured manganese cobalt oxide/carbon composite (Mnco2O4/c) was obtained by using a simple route that combines the hydrothermal method with calcination. The structure is similar to a Russian doll, which is nested with three to four layers of concentric porous shells. The porous multilayer core-shell structures can relieve volume expansion during discharge/charge and reduce the Li-ion diffusion path. Additionally, it can provide a richer activity site, thereby storing more lithium ions. When used as an anode material, the synthesized Mnco2O4/c showed a high specific capacity of 978 mAh g(-1)after 800 cycles at a current density of 1 A g(- 1). Even at a high current density of 10 A g(-1), the electrode could still deliver a specific capacity of 251 mAh g(-1), which makes it more suitable for powering large equipment such as electric vehicles.

关键词： transition metal oxide Mnco2O4 c hollow sphere lithium-ion battery

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Greatly Enhanced Electrocatalytic N2Reduction over V2O3/c by P Doping

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cHEMNANOMAT 2020年第9期6卷 1315-1319页

作者： cheng, Xin Wang, Jianwei Xiong, Wei Wang, Ting Wu, Tongwei Lu, Siyu chen, Guang Gao, Shuyan Shi, Xifeng Jiang, Zhenju Niu, Xiaobin Sun, Xuping Xihua Univ Sch Sci Chengdu 610039 Sichuan Peoples R China Univ Elect Sci & Technol China Inst Fundamental & Frontier Sci Chengdu 610054 Sichuan Peoples R China Zhengzhou Univ Green Catalysis Ctr Zhengzhou 450001 Henan Peoples R China Zhengzhou Univ Coll Chem Zhengzhou 450001 Henan Peoples R China Univ Elect Sci & Technol China Sch Mat & Energy Chengdu 611731 Sichuan Peoples R China Qufu Normal Univ Green Key Lab Life Organ Anal Sch Chem & Chem Engn Qufu 273165 Shandong Peoples R China Qufu Normal Univ Key Lab Pharmaceut Intermediates & Anal Nat Med Sch Chem & Chem Engn Qufu 273165 Shandong Peoples R China Henan Normal Univ Sch Mat Sci & Engn Xinxiang 453007 Henan Peoples R China Shandong Normal Univ Coll Chem Chem Engn & Mat Sci Jinan 250014 Shandong Peoples R China

As a carbon-neutral alternative technology to the Haber-Bosch process, electrochemical N(2)reduction enables eco-friendly NH(3)synthesis under ambient conditions but requires electrocatalysts to drive the N(2)reduction reaction (NRR). Here, P doping is proposed as a valid strategy to greatly increase the NRR activity of the V2O3/c shuttle-like nanostructure. In 0.1 M Na2SO4, the NH(3)yield of original V2O3/c is 12.6 mu g h(-1) mg(cat.)(-1)and a Faraday efficiency (FE) of 6.06% at -0.45 V and -0.25 V vs. reversible hydrogen electrode (RHE), respectively. P-doped V2O3/c (P-V2O3/c), with a mass ratio of P of 6.05%, is capable of achieving a large NH(3)yield of 22.4 mu g h(-1) mg(cat.)(-1)at -0.35 V vs. RHE, and a high FE of 13.78% at -0.25 V vs. RHE. It also shows high electrochemical durability and outstanding selectivity for NH(3)formation. combined with density functional theory calculations, the catalytic mechanism was further explored.

关键词： P doping V2O3 c N(2)reduction reaction ambient NH(3)synthesis density functional theory

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Response of Soil Microbial community to c:N:P Stoichiometry along acaragana korshinskiiRestoration Gradient on the Loess Plateau, china

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FORESTS 2020年第8期11卷 823页

作者： Zhang, Xinyi Li, Wenjie Zhong, Zekun Zhang, Qingyue Wang, Xing Han, Xinhui Ren, chengjie Yang, Gaihe Northwest Agr & Forestry Univ Coll Agron Yangling 712100 Shaanxi Peoples R China Res Ctr Recycle Agr Engn & Technol Shaanxi Prov Yangling 712100 Shaanxi Peoples R China

Soil microorganisms play crucial roles between plants and soil following afforestation. However, the relationship between the microbial community and carbon:nitrogen:phosphorus (c:N:P) stoichiometry in the plant-soil-microbe continuum remains unclear. In this study, we investigated this relationship by collecting plant and soil samples fromcaragana korshinskiiKom. plantations with different years of afforestation (17-, 32-, and 42-year-old plantations), and from farmland. Illumina sequencing of the 16S rRNA and internal transcribed spacer (ITS) ribosomal RNA was used to examine the soil microbial community and the c, N, and P concentrations in plants, soil, and microbial biomass. Other soil characteristics were also measured. The results showed that the c and N concentrations in plants (leaves, herbs, and litter), soil, and microbial biomass increased as the vegetation restoration stage increased, but the P concentration in leaves and herbs slightly decreased. The c:P and N:P ratios in the plant-soil-microbe continuum substantially increased over time, particularly that of the microbial biomass. These results suggest that the unbalanced increase of c, N, and P following vegetation restoration may result in a P limitation in plant-soil systems. Moreover, bacterial and fungal alpha diversity significantly increased following afforestation. Afforestation had a greater impact on bacterial diversity (both alpha and beta diversity) than did fungal diversity. Among the dominant bacterial taxa,Proteobacteriaincreased significantly with afforestation time, whereasActinobacteriadecreased andAcidobacteriapeaked in 32-year-oldc. korshinskiiplantations. However, there were no significant changes in the dominant fungal taxa. collectively, we found that microbial diversity and dominant phyla were closely associated with the c:P and N:P ratios in the plant-soil-microbe continuum, particularly the N:P ratio. These results suggest that microbial diversity and composition may be limit

关键词： soil microbial community c N P stoichiometry the Loess Plateau Illumina sequencing afforestation

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Biological Aging Modulates cell Migration via Lamin A/c-Dependent Nuclear Motion

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MIcROMAcHINES 2020年第9期11卷 801-801页

作者： Park, Jung-Won Han, Seong-Beom Hah, Jungwon Lee, Geonhui Kim, Jeong-Ki Kim, Soo Hyun Kim, Dong-Hwee Korea Univ KU KIST Grad Sch Converging Sci & Technol Seoul 02841 South Korea Korea Inst Sci & Technol Biomed Res Inst Ctr Biomat Seoul 02792 South Korea

Aging is a progressive functional decline in organs and tissues over time and typically represents the accumulation of psychological and social changes in a human being. Diverse diseases, such as cardiovascular, musculoskeletal, and neurodegenerative disorders, are now understood to be caused by aging. While biological assessment of aging mainly focuses on the gradual changes that occur either on the molecular scale, for example, alteration of gene expression and epigenetic modification, or on larger scales, for example, changes in muscle strength and cardiac function, the mechanics that regulates the behavior of individual cells and interactions between the internal elements of cells, are largely missing. In this study, we show that the dynamic features of migrating cells across different human ages could help to establish the underlying mechanism of biological age-dependent cellular functional decline. To determine the relationship between cellular dynamics and human age, we identify the characteristic relationship between cell migration and nuclear motion which is tightly regulated by nucleus-bound cytoskeletal organization. This analysis demonstrates that actomyosin contractility-dependent nuclear motion plays a key role in cell migration. We anticipate this study to provide noble biophysical insights on biological aging in order to precisely diagnose age-related chronic diseases.

关键词： aging cell motility lamin A c nuclear dynamics

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