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11.
An efficient one-pot synthetic methodology has been developed for the benzylic amination reactions of methyl-substituted azine N-oxides that operate under mild conditions. The reaction was found to tolerate quinoline and isoquinoline N-oxides with electron donating and withdrawing substituents as the electrophilic reaction partners as well as a broad range of nucleophilic primary, secondary and aromatic amines, affording the benzylic amination products in up to 82% yield.  相似文献   
12.
CRISPR/Cas9 system is a powerful toolbox for gene editing. However, the low delivery efficiency is still a big hurdle impeding its applications. Herein, we report a strategy to deliver Cas9‐sgPlk‐1 plasmids (CP) by a multifunctional vehicle for tumor therapy. We condensed CPs on TAT peptide‐modified Au nanoparticles (AuNPs/CP, ACP) via electrostatic interactions, and coated lipids (DOTAP, DOPE, cholesterol, PEG2000‐DSPE) on the ACP to form lipid‐encapsulated, AuNPs‐condensed CP (LACP). LACP can enter tumor cells and release CP into the cytosol by laser‐triggered thermo‐effects of the AuNPs; the CP can enter nuclei by TAT guidance, enabling effective knock‐outs of target gene (Plk‐1) of tumor (melanoma) and inhibition of the tumor both in vitro and in vivo. This AuNPs‐condensed, lipid‐encapsulated, and laser‐controlled delivery system provides a versatile method for high efficiency CRISPR/Cas9 delivery and targeted gene editing for treatment of a wide spectrum of diseases.  相似文献   
13.
提出固相萃取分离,毛细管柱气相色谱和质谱联用法测定土壤及蔬菜中三唑酮的残留量.试样用乙腈提取,所得提取液在80℃吹氮至近干,并加正己烷2 mL溶解残渣.此溶液流经填充酸性氧化铝的固相萃取小柱,用正己烷-丙酮(2+1)混合溶剂淋洗小柱,使土壤样品中存在的硫磺与需测定的三唑酮分离.用正己烷一丙酮(1+3)混合溶剂将三唑酮从小柱上解吸洗下,所得洗出液蒸发浓缩,用正己烷定容为5.0 mL供GC-MS分析用.测定中用三唑酮标准溶液制备浓度范围在0.006~1.44 mg·L-1之间的标准曲线.方法的检出限(3S/N)为0.001 mg·kg-1.在3个浓度水平上对方法的回收及精密度作了试验,测得其回收率及相对标准偏差(n=5)依次在84%~92 9,5及1.93%~4.04%之间.  相似文献   
14.
We have demonstrated an approach for the electrostatic assembly of CdTe quantum dots (QDs) with different charged ligands as sensitizers, achieving high coverage and good dispersion in TiO2 porous films. The CdTe QD-sensitized TiO2 porous films were subjected to thermal annealing in a high vacuum chamber to remove the ligand linker, resulting in the formation of direct heterojunctions between the bare CdTe QDs and TiO2 for a favorable charge transfer. The as-received CdTe QD-sensitized TiO2 porous films were employed as photoanodes for quantum dot-sensitized solar cells (QSSCs), and the photocurrent density reached as high as 4.69 mA/cm2 under a standard illumination condition of simulated AM 1.5G (100 mW/cm2).  相似文献   
15.
We study nearly-hamiltonian 2-groups (¯H2-groups). A nonabelian 2-group having at least one proper noncyclic subgroup is called an ¯H2-group if all noncyclic subgroups are normal.Translated from Matematicheskie Zametki, Vol. 4, No. 1, pp. 75–84, July, 1968.The author expresses his deep gratitude towards Professor S. N. Chernikov for guidance while writing this paper.  相似文献   
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17.
Mediterranean Journal of Mathematics - In this paper, we introduce the k-generalized Stockwell transform on $${mathbb {R}}$$ . We investigate for this transform the main theorems of Harmonic...  相似文献   
18.
Translated from Ukrainskii Matematicheskii Zhurnal, Vol. 40, No. 3, pp. 330–335, May–June, 1988.  相似文献   
19.
We study arbitrary infinite 2-groups with three involutions and infinite locally finite p-groups (p2), containing p2–1 elements of order p. For odd p the groupG=a, where A is a direct product of two quasicyclic 3-groups ¦b¦=9, b3A, and subgroup A is generated by the elements of the commutator ladder of element b, is a unique infinite non-Abelian locally finite p-group whose equation xP=1 has p2 solutions.Translated from Matematicheskie Zametki, Vol. 20, No. 1, pp. 11–18, July, 1976.  相似文献   
20.
为了明确储层沥青热演化程度与激光拉曼光谱的关系,利用拉曼光谱无损分析和流体包裹体方法,对黔西南白层地区储层沥青拉曼光谱进行了定量化描述,首先获取了储层沥青其伴生流体包裹体均一温度,然后获得了储层沥青拉曼光谱图,并对比标准沥青成熟度分布图,确定了储层沥青热演化程度及其特征.结果表明:黔西南白层地区存在晚三叠世(230 M...  相似文献   
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