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101.
102.
A phosphine-mediated synthesis of trifluoromethyl substituted pyrrole derivatives was achieved. The method described here is very fast, operationally simple, and easily amenable to scale-up, and commercially available trifluoroacetic anhydride (TFAA) is used as the only trifluoromethyl source. A wide range of products were obtained with good yields under mild condition using this method.  相似文献   
103.
Raman spectra of iodine species confined in one‐dimensional elliptical channels of AlPO4‐11 (AEL) crystals have been studied from room temperature down to −196 °C. As temperature decreases, thermal fluctuations of individual iodine molecules confined in AEL channels are slowed down and they prefer to rotate to channel axis direction, which increases the population of iodine molecules along channel axis (i.e., lying molecules and chains). Such temperature‐driven orientation transformation of iodine molecules is found to be reversible upon heating up to room temperature. The experimental observations are in good agreement with our theoretical simulations by molecular dynamics on low density iodine‐filled AEL crystals. We thus provide a new way to modulate the orientation of iodine molecules in nanochannels, which may have implications in low‐temperature‐sensitive nanoscale devices. Copyright © 2015 John Wiley & Sons, Ltd.  相似文献   
104.
Yue  Hangbo  Xu  Chao  Yao  Jiachang  He  Ming  Yin  Guoqiang  Cui  Yingde  Yang  Chufen  Guo  Jianwei 《Cellulose (London, England)》2022,29(10):5869-5881
Cellulose - The development of plant adhesive with good bonding strength, water resistance and thermal stability remains challenging to replace formaldehyde-based adhesive resins that usually...  相似文献   
105.
Nucleic acid–based electrochemical sensors are ideally suited to the detection of molecular targets for which enzymatic detection or direct electrochemical oxidation – reduction reactions are not possible. Moreover, the versatility of nucleic acids in their ability to bind a great variety of target types, from small molecules to single-entity mesoscopic targets, makes them attractive receptors for the development of electrochemical biosensors. In this brief opinion piece, we discuss field advances from the past two years. We hope the works highlighted here will inspire the community to pursue creative designs enabling the detection of larger and more complex targets with a specific focus on analytical validation and translation into preclinical or clinical applications.  相似文献   
106.
To ensure sustainable hydrogen production by water electrolysis, robust, earth‐abundant, and high‐efficient electrocatalysts are required. Constructing a hybrid system could lead to further improvement in electrocatalytic activity. Interface engineering in composite catalysts is thus critical to determine the performance, and the phase‐junction interface should improve the catalytic activity. Here, we show that nickel diphosphide phase junction (c‐NiP2/m‐NiP2) is an effective electrocatalyst for hydrogen production in alkaline media. The overpotential (at 10 mA cm?2) for NiP2‐650 (c/m) in alkaline media could be significantly reduced by 26 % and 96 % compared with c‐NiP2 and m‐NiP2, respectively. The enhancement of catalytic activity should be attributed to the strong water dissociation ability and the rearrangement of electrons around the phase junction, which markedly improved the Volmer step and benefited the reduction process of adsorbed protons.  相似文献   
107.
Cai  Mengmeng  Yao  Lijuan  Zhu  Man  Tao  Peng  Nan  Ruihua  Jian  Zengyun 《Journal of Thermal Analysis and Calorimetry》2021,143(4):2911-2918
Journal of Thermal Analysis and Calorimetry - Differential scanning calorimetry was used to investigate the non-isothermal crystallization kinetics of the Fe76.5Nb3B20Cu0.5 glassy alloys. The...  相似文献   
108.
Twelve compounds, including two new aristolochic acid analogues with a formyloxy moiety (9–10) and 10 known aristolochic acid derivates (1–8 and 11–12), were obtained from the roots of Aristolochia contorta. Their structures were elucidated using extensive spectroscopic methods. Their cytotoxic activity in human proximal tubular cells HK-2 was evaluated by the MTT method, which has been widely used to assess cell viability. Among these molecules, compounds 3 and 9 were found to be more cytotoxic. Furthermore, molecular modeling was used to evaluate, for the first time, the interactions of compounds 3 and 9 with the target protein organic anionic transporter 1 (OAT1) that plays a key role in mediating aristolochic acid nephropathy. Structure–activity relationships are briefly discussed.  相似文献   
109.
WeiPing Liu  ZhiHong Li  JiangJun He  XiaoDong Tang  Gang Lian  Zhu An  JianJun Chang  Han Chen  QingHao Chen  XiongJun Chen  ZhiJun Chen  BaoQun Cui  XianChao Du  ChangBo Fu  Lin Gan  Bing Guo  GuoZhu He  Alexander Heger  SuQing Hou  HanXiong Huang  Ning Huang  BaoLu Jia  LiYang Jiang  Shigeru Kubono  JianMin Li  KuoAng Li  Tao Li  YunJu Li  Maria Lugaro  XiaoBing Luo  HongYi Ma  ShaoBo Ma  DongMing Mei  YongZhong Qian  JiuChang Qin  Jie Ren  YangPing Shen  Jun Su  LiangTing Sun  WanPeng Tan  Isao Tanihata  Shuo Wang  Peng Wang  YouBao Wang  Qi Wu  ShiWei Xu  ShengQuan Yan  LiTao Yang  Yao Yang  XiangQing Yu  Qian Yue  Sheng Zeng  HuanYu Zhang  Hui Zhang  LiYong Zhang  NingTao Zhang  QiWei Zhang  Tao Zhang  XiaoPeng Zhang  XueZhen Zhang  ZiMing Zhang  Wei Zhao  Zuo Zhao  Chao Zhou  JUNA Collaboration 《中国科学:物理学 力学 天文学(英文版)》2016,59(4):642001
Jinping Underground laboratory for Nuclear Astrophysics(JUNA) will take the advantage of the ultra-low background of CJPL lab and high current accelerator based on an ECR source and a highly sensitive detector to directly study for the first time a number of crucial reactions occurring at their relevant stellar energies during the evolution of hydrostatic stars. In its first phase, JUNA aims at the direct measurements of~(25)Mg(p,γ)~(26)Al,~(19)F(p,α)~(16)O,~(13)C(α,n)~(16)O and ~(12)C(α,γ)~(16)O reactions. The experimental setup,which includes an accelerator system with high stability and high intensity, a detector system, and a shielding material with low background, will be established during the above research. The current progress of JUNA will be given.  相似文献   
110.
The electronic structure and the magnetic properties of transition metal phosphonate Co(PhPO3)·H2O have been studied by first-principles within the density-functional theory (DFT) and the full potential linearized augmented plane wave (FP-LAPW) method. The total energy, the total magnetic moment, the atomic spin magnetic moments and the density of states(DOS) of Co(PhPO3)·H2O were all calculated. The calculations reveal that the title compound is a metallic antiferromagnet and has a metallic ferromagnetic metastable state, which are in good agreement with the experiment. The spin magnetic moment of Co(PhPO3)·H2O is about 4.93 μBμB per molecule, and it is mainly assembled at the cobalt atom, at the same time, with a little contribution from the P, O1, O2, O3.  相似文献   
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