小麦垂直农场(vertical wheat farms,VWF)是在传统的二维农业模式基础上,近几十年发展起来的新型三维立体农业种植模式,具有单位土地面积利用效率高、环境友好、绿色无公害、
In this paper,a series of ReaxFF molecular dynamic simulations were performed to study the oxidation of chemical passivated silicon(100) surface,which was termi
Main observation and conclusion Alkoxy radical-mediated carbon-carbon bond cleavages have emerged as a powerful strategy to complement traditional ionic-type transformations.However,carbon-carbon cleavage reaction triggered by alkoxy radical intermediate
High CO pressure (＞ 40 bar) is usually needed in radical carbonylation reactions in the absence of metal catalyst.In this communica-tion,we developed a transitio
Natural products and their derivatives have long been used as medicinal agents,and they still make up a significant fraction of clinically approved drugs.Natura
在中国,有情怀的古镇有很多,如丽江、凤凰、婺源、周庄、乌镇……它们宛如一颗颗明珠,镶嵌在中华大地上,散发着迷人的光泽。在广西北海,也有一个形成于19世纪的古镇,面朝烟波浩渺的廉州湾,静静地偏于城市一隅,至今仍保留着纯正的渔家生活风貌。它,就是高德古镇。历史记载,高德是北海开埠较早的港口之一,
The first example of Rh-catalyzed kinetic resolution of 1,3-disubstituted allene-1,3-dienes involving intramolecular[4+2]-cycloaddition has been developed.Follo
基于密度泛函理论和卡里普索结构预测方法,系统研究了 VnB8(n+1)-(n=1-3)团簇的几何结构、电子和光谱特性.首先,利用卡里普索结构预测方法确定了 VB16-的基态结构为高对称性
The reaction of 2-alkynylanisoles/sulfides with SOCl2 and DMSO was conducted to conveniently furnish the biologically interesting 3-(methylthio)-benzo[b]furans/
“秘密”是知识与信念中的一个重要概念,也是信息网络隐私与安全所讨论的重要对象。文章从知识逻辑与信念逻辑两个方面分析了“秘密”的逻辑语义,并给出了其归约公理以及基于知识逻辑与信念逻辑的完全的公理化系统。然后从知识逻辑与信念逻辑两个方面剖析“纯秘密逻辑系统”的公理与规则,发现它们都是一个非正规模态逻辑系统ECKT4的扩张,这两个“纯秘密逻辑系统”只在讨论不同主体间的互动推理时存在差异,只是这两个系统的完全性问题还有待进一步研究。