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上海硅酸盐所在光催化还原CO2制备C2产物研究中取得系列进展(图)
光催化还原 CO2制备 C2产物
2022/12/28
化石燃料的使用产生了大量的二氧化碳 (CO2),过量排放的CO2造成了全球气候变暖、海平面升高等一系列问题。有效控制和降低大气中的CO2浓度直接关系到可持续发展。光催化模拟植物的光合作用,利用太阳光将CO2和水转化为含碳化学品,在减少大气中CO2含量的同时,获得高附加值的C1化合物(CO、甲烷等)和C2+化合物(乙醇、乙酸等),具有绿色、可持续等优点,因而富有深远的发展潜力。其中,由于C2+产物具...
Cu(F-Cu)催化CO2电还原为C2+产物(图)
Cu(F-Cu)催化 CO2电还原 C2+
2022/6/15
以双夹板形的笼型倍半硅氧烷(DDSQ)和叔丁基氧羰基(Boc)保护的C2-对称双脯氨酰胺为底物,通过硅氢加成反应和脱Boc反应,制得主链含DDSQ的C2-对称双脯氨酰胺手性聚合物催化剂;对其化学结构、分子量及热失重性能进行了表征. 将制备的聚合物催化剂应用于催化不对称Aldol反应,探讨了其催化性能. 结果表明,催化产物均具有较高的产率和立体选择性,且该催化剂便于分离纯化,循环使用6次后催化活性未...
A Compactification of H′ enon Mappings in C2 as Dynamical Systems
H′ enon Mappings C2 as Dynamical Systems
2015/8/26
A Compactification of H′ enon Mappings in C2 as Dynamical Systems.
New Tight Frames of Curvelets and Optimal Representations of Objects with C2 Singularities
Curvelets wavelets second dyadic decomposition edges nonlinear approximation singularities thresholding Radon transform
2015/6/17
This paper introduces new tight frames of curvelets to address the problem of finding optimally sparse representations of objects with discontinuities along C2 edges.Conceptually, the curvelet transfo...
Human Niemann-Pick Type C2 Disease Protein Expression, Purification and Crystallization
Niemann-Pick type C2 NPC2 Structure Expression Crystallization Purification
2014/12/12
Niemann-Pick type C2 (NPC2) protein is a soluble protein that binds unesterified cholesterol. The protein helps transport unesterified cholesterol in tandem with the membrane protein Niemann-Pick type...
使用极化分子力场对两种锂盐浓度均为0.32 mol/kg的咪唑型离子液体电解质体系, LiFSI-[EMIM][FSI]和LiFSI-[EMMI][FSI], 进行了分子动力学模拟. 通过分析Li+离子和emim+/emmi+阳离子的溶剂化层结构, 研究发现Li+与阴离子FSI-较强的静电作用受咪唑阳离子结构变化的扰动微小, C2位甲基化明显改变的是离子液体中离子间的作用结构. 结合自相关函数的计...
Anisotropic $H_{c2}$ determined up to 92 T and the signature of multi-band superconductivity in Ca$_{10}$(Pt$_{4}$As$_{8}$)((Fe$_{1-x}$Pt$_{x}$)$_{2}$As$_{2}$)$_{5}$ superconductor
Anisotropic signature multi-band superconductivity superconductor
2012/2/27
The upper critical fields, $H_{c2}$($T$), of single crystals of the superconductor Ca$_{10}$(Pt$_{4-\delta}$As$_{8}$)((Fe$_{0.97}$Pt$_{0.03}$)$_{2}$As$_{2}$)$_{5}$ ($\delta$ $\approx$ 0.246) are deter...
复苏植物旋蒴苣苔C2结构域小蛋白BhC2DP1参与植物对ABA的反应
ABA C2结构域 干旱 复苏植物
2012/3/23
为揭示植物抗旱的调控机理, 对复苏植物旋蒴苣苔(Boea hygrometrica)的一个编码C2结构域小蛋白的基因BhC2DP1进行研究。Real-time PCR和ProBhC2DP1:GUS报告基因检测显示, 该基因只在干旱早期和外源Ca2+处理0.5小时时受诱导表达; 分别施加Ca2+螯合剂EGTA和逆境激素ABA均抑制该基因表达, 但二者同时处理则显著诱导其表达, 表明ABA对该基因转录...
立方相Y2O3:Eu纳米晶中C2格位Eu3+的5D0能级量子效率
量子效率 荧光衰减 纳米 Y2O3:Eu3+
2011/12/13
采用化学自发燃烧法制备了立方相不同粒径的纳米晶Y203:Eu(1 mo1%),并通过退火处理得到了体相材料,测量了它们的发射谱和处在C2格位上E 的 D0能级室温和1O K下的荧光衰减曲线。利用发射光谱数据计算了Eu3+在不同粒径纳米晶体Y2O3中的光学跃迁强度参数 ( =2,4),通过对室温和低温下 D0能级荧光衰减的测量,用两种不同方法估计了处在格位上Eu3+的 D0能级的量子效率,对所获得的...
Quasi-classical Trajectory Study of C+CD→C2+D at Different Collision Energy
Quasi-classical trajectory Stereodynamics calculation Polarization depen-dent generalized differential cross-section Stereodynamics
2012/4/5
Quasi-classical trajectory calculations have been employed to investigate the influence of collision energy on the stereodynamics of the title reaction C+CD→C2+D on the poten-tial energy surface of th...
Observed and simulated global distribution and budget of atmospheric C2-C5 alkanes
global distribution atmospheric C2-C5 alkanes
2010/8/12
The primary sources and atmospheric chemistry of C2-C5 alkanes were incorporated into the atmospheric chemistry general circulation model EMAC. Model output is compared with new observations from the ...
Branching fraction measurements of \chi_{c0} and \chi_{c2} to \pi^0\pi^0 and \eta\eta
Branching fraction \chi_{c2} \eta\eta
2010/3/15
Using a sample of 1.06 \times 10^8 \psi^{\prime} decays collected by the BESIII detector, \chi_{c0} and \chi_{c2} decays into \pi^0\pi^0 and \eta\eta are studied. The branching fraction results are Br...
C2轴对称樟脑磺酰胺基醇配体催化环己烯乙炔对酮的不对称加成反应
C2轴对称樟脑磺酰胺基醇 不对称催化 环己烯乙炔
2009/11/16
应用C2轴对称的樟脑磺酰胺基醇配体和Cu(OTf)2催化带官能团的环己烯乙炔对酮的不对称加成反应. 芳香酮、脂肪酮和杂环酮都适用于此体系, 并且在室温下最高e.e.值约为89%, 其中脂肪酮首次被应用于此反应, 极大地扩展了底物的范围. 研究结果表明, 脂肪酮的立体位阻对反应的对映选择性起着至关重要的作用.