In this article, we present density functional theory (DFT) calculations on the iron(IV)-oxo catalyzed methane C-H activation reactions for complexes in which Fe(IV)═O core is surrounded by five negatively charged ligands. We found that it follows a hybrid pathway mixes features of classical σ- and π-pathways quintet surfaces. These show Fe-O-H arrangement bent sharp contrast to collinear character as observed σ-pathways before. The have also shown equatorial ligands play key roles tuning...

Surface plasmon coupled emission (SPCE) is a new analytical technique that provides increased and directional radiation based on the near-field interaction between fluorophores surface plasmons but suffers from limitation of insufficient sensitivity. The assembly hollow-porous plasmonic nanoparticles could be qualified candidate. After introduction gold nanocages (AuNCs), fluorescence signal enhancement was realized by factors over 150 600 compared with normal SPCE free space emission,...

Alkane C-H bond activation by various catalysts and enzymes has attracted considerable attention recently, but many issues are still unanswered. The conversion of ethane to ethanol ethene bare [Fe(III)═O](+) been explored using density functional theory coupled-cluster method comprehensively. Two possible reaction mechanisms available for the entire reaction, direct H-abstraction mechanism concerted mechanism. First, in mechanism, a is encountered initial step, going through collinear...

Synthesis, solvent-, and guest-controlled self-assembly, self-sorting of new hydrogen-bonded chiral cavity receptors are reported. The design the is based on cyclic self-aggregation monomers containing 4H-bonding ureidopyrimidinone motif fused with bicylo[3.3.1]nonane framework. Selective formation kinetically inert tetramers observed in chloroform, while toluene an equilibrium between tetrameric pentameric forms exists. high affinity aggregates toward C60 C70 aromatic solvents. host-guest...

Abstract The reaction of C 2 (A 3 Π u ) with CH 4 has been investigated over a wide temperature range 200–3,000 K by direct ab initio dynamics method at the BMC‐CCSD//BB1K/6‐311+G(2d,2p) level theory. optimized geometries and frequencies stationary points are calculated BB1K/6‐311+G(2d,2p) level, then energy profiles reactions refined using BMC‐CCSD method. activation barrier height for H‐abstraction was to be 4.44 kcal/mol in (337–605 K), electron transfer behavior also analyzed...

The methane (CH4) hydrogen abstraction reaction by linear butadiynyl radical C4H (CCCCH) has been investigated direct ab initio dynamics over a wide temperature range of 100−3000 K, theoretically. potential energy surfaces (PESs) have constructed at the CCSD(T)/aug-cc-pVTZ//BB1K/6-311G(d,p) levels theory. Two different channels C1 and C4 (C1C2C3C4H) considered. results indicate that position is more reactive site. electron transfer behaviors two possible are also analyzed quasi-restricted...

X Σ )＋H 2 反应机理的直接动力学研究 霍瑞萍 a 张祥 b 黄旭日 李吉来 * ,a 孙家锺 ( 吉林大学理论化学研究所理论化学国家重点实验室 长春 130023) 山西师范大学化学与材料科学学院 临汾 041004) 摘要 贫氢分子 C n H 是燃烧火焰、行星大气中的重要的中间体. 这些分子与其它一些分子或自由基的反应在星际化学 中起着非常重要的作用.虽然这些分子的电子结构和光谱性质已经进行了广泛的研究, 但是研究这些反应的机理和动 力学性质也是亟需的.因此, 我们采用直接动力学方法对线性分子丁二炔自由基 4 H(CCCCH)夺氢气(H )分子中 HAT 的反应的微观机理和动力学性质进行了理论研究.本研究分别在 BB1K/6-311＋G(2d,2p), B3LYP/6-311＋G(2d,2p)和 M06-2x/6-311＋G(2d,2p)水平上优化得到了各稳定点的结构及振动频率.为了得到更为可靠的反应能量和势能面信息, 在 BB1K/6-311＋G(2d,2p)优化结构的基础上用 CCSD(T)/aug-cc-pVTZ 水平进行了单点能量校正.对于此反应研究了两...

The multiple electronic state mechanisms of the reaction carboryne with benzene were investigated by M11 calculations. Mechanisms leading to [4 + 2] cycloaddition product P 4 2 , [2 CC insert C‐Cins and CH C‐Hins considered. barrier/stability structural characteristics correlations revealed that, 1) addition is a two‐step mechanism which exhibits three reactivity, both steps are controlled barriers on open‐shell singlet (OSS) potential energy surface (PES); 2) kinetic experimental...

An alternative metric for evaluating insulin resistance (IR) is the triglyceride glucose-body mass index (TyG-BMI). However, it yet unclear how TyG-BMI and suicide attempts (SA) are related. The objective of this research was to explore correlation between SA in individuals with untreated first-episode (UFE) major depressive disorder (MDD) Shanxi Province. This cross-sectional study conducted from September 2016 December 2018 psychiatric outpatient clinic Taiyuan General Hospital included...

Plasmonic regulation introduced by metallic nanoparticles is a useful method to improve the detection performance of plasmon-based systems. Herein, we observed unique enhancement surface plasmon-coupled emission (SPCE) using plate-shaped plasmonic nanostructures. By assembling Au nanoplates (Au NPLs) via electrostatic adsorption between nanofilm and quantum dot (QD) layer (630 nm), fluorescence signal SPCE was enhanced 90 times more than that normal after conditions were optimized. This...

Abstract The mechanism of the reaction 1,3‐bis (amino)‐2‐phosphaallyl chlorides with hydrazine for synthesis 1H‐1,2,4‐diazaphospholes in CHCl 3 solvent has been extensively investigated at B3LYP/6‐311G (d, p) level. is initiated by elimination HCl and formation a key intermediate A , then subsequently undergoes H‐migration‐cyclization ( → B ) Me 2 NH reactions C to afford carbene can transform F along both single triplet potential energy surfaces three steps. step was identified as...

The ruthenium(II)-catalyzed α-alkylation reaction of arylmethyl nitriles (phenylacetonitrile) using alcohols (ethanol) in toluene has been extensively investigated by means SMD-M06-2X/6-311G(d,p)-LANL2dz (LAnL2dz for Ru, 6-311G(d,p) other atoms) calculations. Detailed mechanistic schemes have proposed and discussed. catalytically active Ru(II) complex was generated the base-induced KCl elimination from catalyst precursor [(PNPPh)RuHCl(CO)]. overall catalytic cycle consists three basic...

In order to improve the visualization and efficiency of transformer temperature monitoring, a real-time detection system based on Django network framework is designed, in which acquisition module composed sensor zigbee controlled by Raspberry Pi microcomputer. The server monitoring are partly B / S architecture design, python language used collect, store, send display data. Users through web browser view data displayed form charts facilitate analysis warning equipment.

<p>Although there have been good developments in China’s construction industry with increasing building technology and design levels, are still some issues that require attention to be solved by designers constructing structure designs. The stability of the quality can only ensured continual rectifying solving problems structural design. In this study, discussion examines encountered actual work.</p>

<p>Although there have been good developments in China’s construction industry with increasing building technology and design levels, are still some issues that require attention to be solved by designers constructing structure designs. The stability of the quality can only ensured continual rectifying solving problems structural design. In this study, discussion examines encountered actual work.</p>

The mechanism of the transition metal manganese complex Mn(PhPNN)(CO)2Br (CA-4) that catalyzed hydrogenation azo (N═N) bond to amines has been investigated using PBE0 function. results show whole reaction involves three basic processes: (1) addition H2 CA gives IN2, which can hydrogenate at later stage; (2) azobenzene by 1,2-diphenylhydrazine (PhNHNHPh); and (3) affords aniline (PhNH2). suggest IN2 afford PhNHNHPh are easy occur due low barriers, overall rate-determining step is formation...