Numerical and experimental analysis on green laser crystallization of amorphous silicon thin films

The laser fluence effect on crystallization of amorphous silicon irradiated by a frequency-doubled Nd: YAG laser has been studied both theoretically and experimentally. An effective numerical model is set up to predict the melting threshold and the optimized laser fluence for crystallization of 200nm amorphous silicon. Temperature distribution with time and melt depth are analyzed. Besides the model, Raman spectra of thin films treated with different fluences are measured to confirm the phase transition and to determine the optimized fluence. The calculating results accord well with those obtained from the experimental data in this research

AIDA directly connects sympathetic innervation to adaptive thermogenesis by UCP1

AIDA最早是由林圣彩教授团队首先鉴定和命名的。2007年林圣彩教授团队与孟安明院士团队合作发现AIDA在斑马鱼体轴发育中的功能(Rui, 2007)。2018年，林圣彩教授团队首次发现了AIDA在哺乳动物中的功能，即AIDA介导的内质网降解途径通过降解脂肪合成途径中的关键酶，而限制膳食脂肪在肠道的吸收这一内在抵御肥胖(Luo, 2018)。而本次成果揭示了AIDA在棕色脂肪组织中特定的功能。这些工作将AIDA引入了脂质应激代谢的重要环节，包括脂质吸收和依赖于脂质的产热过程。该论文的共同第一作者为生命科学学院博士生史猛和硕士生黄晓羽，林圣彩教授和林舒勇教授则为共同通讯作者。【Abstract】The sympathetic nervous system–catecholamine–uncoupling protein 1 (UCP1) axis plays an essential role in non-shivering adaptive thermogenesis. However, whether there exists a direct effector that physically connects catecholamine signalling to UCP1 in response to acute cold is unknown. Here we report that outer mitochondrial membrane-located AIDA is phosphorylated at S161 by the catecholamine-activated protein kinase A (PKA). Phosphorylated AIDA translocates to the intermembrane space, where it binds to and activates the uncoupling activity of UCP1 by promoting cysteine oxidation of UCP1.Adipocyte-specific depletion of AIDA abrogates UCP1-dependent thermogenesis, resulting in hypothermia during acute cold exposure. Re-expression of S161A-AIDA, unlike wild-type AIDA, fails to restore the acute cold response in Aida-knockout mice.The PKA–AIDA–UCP1 axis is highly conserved in mammals, including hibernators. Denervation of the sympathetic postganglionic fibres abolishes cold-induced AIDA-dependent thermogenesis. These findings uncover a direct mechanistic link between sympathetic input and UCP1-mediated adaptive thermogenesis.We thank Y. Li, E. Gnaiger, T. Kuwaki, J. R. B. Lighton, E. T. Chouchani and D. Jiang for technical instruction; X. Li and X.-D. Jiang (Core Facility of Biomedical, Xiamen University) for raising the p-S161-AIDA antibody; the Xiamen University Laboratory Animal Center for the mouse in vitro fertilization service and all the other members of S.C.L. laboratory for their technical assistance. This work was supported by grants from the National Key Research and Development Project of China (grant no. 2016YFA0502001) and the National Natural Science Foundation of China (grant nos 31822027, 31871168, 31690101, 91854208 and 82088102), the Fundamental Research Funds for the Central Universities (grant nos 20720190084 and 20720200069), Project ‘111’ sponsored by the State Bureau of Foreign Experts and Ministry of Education of China (grant no. BP2018017), the Youth Innovation Fund of Xiamen (grant no. 3502Z20206028), the Natural Science Foundation of Fujian Province of China (grant no. 2017J01364) and XMU Training Program of Innovation and Entrepreneurship for Undergraduates (grant no. 2019×0666). 该工作得到了厦门大学实验动物中心和生物医学学部仪器平台的重要协助和国家重点研究和发展项目，国家自然科学基金，厦门大学校长基金等的支持

Foot measurements from 2D digital images

Foot measurements play an important role in the design of comfortable footwear products. This study proposed a non-invasive and efficient means to obtain foot measurements from 2D digital foot images. The hardware of the proposed image-based measuring system was easy to set up and the developed measuring system was tested for 9 foot measurements with ten male subjects who were also manually measured. The comparison between foot measurements from the image-based and the traditionally manual measured systems showed that there were no significant differences between two systems on 8 out of 9 foot measurements. The errors on foot measurements from the image-based system were also analyzed and discussed. The proposed image-based system under further improvements may be applied into the online sales of shoes, especially customized shoes

Oxidative kinetic resolution of racemic secondary alcohols in water with chiral PNNP/Ir catalyst

National Natural Science Foundation of China [20423002, 20923004, 21173176]; NFFTBS [J1030415]; Program for Changjiang Scholars and Innovative Research Team in University [IRT1036]; State Key Laboratory of Physical Chemistry of Solid SurfacesUsing water as solvent, the oxidative kinetic resolution of a wide range of racemic secondary alcohols with a chiral PNNP/Ir catalyst was investigated. The catalytic reaction proceeded smoothly with excellent enantioselectivity (up to 97% ee) under mild conditions, providing an environmentally benign process to achieve optically active alcohols

Iron-Catalyzed Highly Enantioselective Reduction of Aromatic Ketones with Chiral P2N4-Type Macrocycles

National Natural Science Foundation of China [20423002, 20923004, 21173176]; Program for Changjiang Scholars and Innovative Research Team in University [IRT1036]; State Key Laboratory of Physical Chemistry of Solid SurfacesNovel P2N4-donors containing chiral 22-membered macrocyclic ligands have been synthesized and the structures have been determined by an X-ray diffraction study. The catalytic systems in situ generated from triiron dodecarbonyl, Fe3(CO)12, and the chiral macrocyclic ligand exhibited high activity (TOF up to 1940 h-1) and excellent enantioselectivity with up to 99% ee in the asymmetric transfer hydrogenation of various aromatic ketones

Iron catalyzed asymmetric hydrogenation of ketones

Chiral molecules, such as alcohols, are vital for the manufacturing of fine chemicals, pharmaceuticals, agrochemicals, fragrances, and novel materials. These molecules need to be produced in high yield and high optical purity and preferentially catalytically. Among all the asymmetric catalytic reactions, asymmetric hydrogenation with H2 (AH) is the most widely used in the industry. With few exceptions, these AH processes use catalysts based on the three critical metals, rhodium, ruthenium, and iridium. Herein we describe a simple, industrially viable iron catalyst that allows for the AH of ketones, a process currently dominated by ruthenium and rhodium catalysts. By combining a chiral, 22-membered macrocyclic ligand with the cheap, readily available Fe 3(CO)12, a wide variety of ketones have been hydrogenated under 50 bar H2 at 45-65 C, affording highly valuable chiral alcohols with enantioselectivities approaching or surpassing those obtained with the noble metal catalysts. In contrast to AH by most noble metal catalysts, the iron-catalyzed hydrogenation appears to be heterogeneous. ? 2014 American Chemical Society

Iron Catalyzed Asymmetric Hydrogenation of Ketones

Chiral molecules, such as alcohols, are vital for the manufacturing of fine chemicals, pharmaceuticals, agrochemicals, fragrances, and novel materials. These molecules need to be produced in high yield and high optical purity and preferentially catalytically. Among all the asymmetric catalytic reactions, asymmetric hydrogenation with H₂ (AH) is the most widely used in the industry. With few exceptions, these AH processes use catalysts based on the three critical metals, rhodium, ruthenium, and iridium. Herein we describe a simple, industrially viable iron catalyst that allows for the AH of ketones, a process currently dominated by ruthenium and rhodium catalysts. By combining a chiral, 22-membered macrocyclic ligand with the cheap, readily available Fe₃(CO)₁₂, a wide variety of ketones have been hydrogenated under 50 bar H₂ at 45–65 °C, affording highly valuable chiral alcohols with enantioselectivities approaching or surpassing those obtained with the noble metal catalysts. In contrast to AH by most noble metal catalysts, the iron-catalyzed hydrogenation appears to be heterogeneous

Aerobic and Efficient Direct Arylation of Five-Membered Heteroarenes and Their Benzocondensed Derivatives with Aryl Bromides by Bulky α‑Hydroxyimine Palladium Complexes

In the present work, a series of α-hydroxyimine palladium complexes with bulky substituents (i.e., {[Ar-NC­(R)–C­(R)₂–OH]­PdCl₂} (<b>C1</b>, R = Me, Ar = 2-diphenylmethyl-4,6-dimethylphenyl; <b>C2</b>, R = Me, Ar = 2,6-bis­(diphenylmethyl)-4-methylphenyl; <b>C3</b>, R = Me, Ar = 2,6-bis­(diphenylmethyl)-4-methyoxylphenyl; <b>C4</b>, R = Me, Ar = 2,6-bis­(diphenylmethyl)-4-chlorophenyl; <b>C5</b>, R = Ph, Ar = 2,6-dimethylphenyl; <b>C6</b>, R = Ph, Ar = 2,6-diisopropylphenyl)) were synthesized and characterized. The structures of palladium complexes <b>C1</b> and <b>C2</b> were determined by X-ray diffraction. These bidentate N,O-palladium complexes were applied for direct arylation under aerobic conditions. The effects of the reaction conditions and ligand substitution on the catalytic activity were evaluated. Upon a low palladium loading of 0.5 mol %, the bulky palladium complex <b>C6</b> was successfully used to catalyze the cross-coupling of a variety of five-membered heteroarenes and their benzo-condensed derivatives with (hetero)­aryl bromides. The mechanistic investigation on the direct arylation supported the involvement of a Pd(0)/Pd­(II) CMD process

Aerobic and Efficient Direct Arylation of Five-Membered Heteroarenes and Their Benzocondensed Derivatives with Aryl Bromides by Bulky α‑Hydroxyimine Palladium Complexes

In the present work, a series of α-hydroxyimine palladium complexes with bulky substituents (i.e., {[Ar-NC­(R)–C­(R)₂–OH]­PdCl₂} (<b>C1</b>, R = Me, Ar = 2-diphenylmethyl-4,6-dimethylphenyl; <b>C2</b>, R = Me, Ar = 2,6-bis­(diphenylmethyl)-4-methylphenyl; <b>C3</b>, R = Me, Ar = 2,6-bis­(diphenylmethyl)-4-methyoxylphenyl; <b>C4</b>, R = Me, Ar = 2,6-bis­(diphenylmethyl)-4-chlorophenyl; <b>C5</b>, R = Ph, Ar = 2,6-dimethylphenyl; <b>C6</b>, R = Ph, Ar = 2,6-diisopropylphenyl)) were synthesized and characterized. The structures of palladium complexes <b>C1</b> and <b>C2</b> were determined by X-ray diffraction. These bidentate N,O-palladium complexes were applied for direct arylation under aerobic conditions. The effects of the reaction conditions and ligand substitution on the catalytic activity were evaluated. Upon a low palladium loading of 0.5 mol %, the bulky palladium complex <b>C6</b> was successfully used to catalyze the cross-coupling of a variety of five-membered heteroarenes and their benzo-condensed derivatives with (hetero)­aryl bromides. The mechanistic investigation on the direct arylation supported the involvement of a Pd(0)/Pd­(II) CMD process