Solvent effects in electrocoagulation of selected plant pigments and tannin

Electrocoagulation of a plant extract and certain substances representative of selected classes of plant pigments, viz. chlorophyll, a carotenoid, a phenolic substance and a tannin, was performed in ethanol containing varying amounts of water (15-75%). The results showed that the extent and efficiency of coagulation of these substances tends to vary in a manner directly related to the water content of the solvent, although the tannin and the phenolic substance were less sensitive to the solvent composition and are equally well coagulated in all solvent systems studied. The findings can be applied to the removal of these substances from aqueous alcoholic plant extracts using the electrocoagulation technique.     

Substrate tuned reconstructed polymerization of naphthalocyanine on Ag(110)

The linkage structures between monomers make great influence on the properties of polymers.The synthesis of some special linkage structures can be challenging,which is often overcome by employing special reaction conditions.Here,we build dihydropentalene linkage in poly-naphthalocyanine on Ag(110)surface.Scanning tunneling microscopy(STM)and non-contact atomic force microscopy(nc-AFM)measurements confirm the dihydropentalene linkage structure and a possible formation path with reconstruction steps is proposed.The controlled experiment on Ag(100)surface shows no dihydropentalene structures formed,which indicates the grooved substrate is necessary for the reconstruction.This work provides insights into the surface restricted reactions that can yield special structures in organic polymers.     

Enhancing the Production of <Emphasis Type="SmallCaps">d</Emphasis>-Mannitol by an Artificial Mutant of <Emphasis Type="Italic">Penicillium</Emphasis> sp. T2-M10

d-Mannitol belongs to a linear polyol with six-carbon and has indispensable usage in medicine and industry. In order to obtain more efficient d-mannitol producer, this study has screened out a stable mutant Penicillium sp. T2-M10 that was isolated from the initial d-mannitol-produced strain Penicillium sp.T2-8 via UV irradiation as well as nitrosoguanidine (NTG) induction. The mutant had a considerable enhancement in yield of d-mannitol based on optimizing fermentation. The production condition was optimized as the PDB medium with 24 g/L glucose for 9 days. The results showed that the production of d-mannitol from the mutant strain T2-M10 increased 125% in contrast with the parental strain. Meanwhile, the fact that d-mannitol is the main product in the mutant simplified the process of purification. Our finding revealed the potential value of the mutant strain Penicillium sp. T2-M10 to be a d-mannitol-producing strain.     

腕部手厥阴心包经区域光传输特性的蒙特卡罗模拟

基于腕部手厥阴心包经循行区域的解剖结构,建立了腕部手厥阴心包经和旁开非经络线区域组织光传输结构的简化模型,并利用蒙特卡罗模拟的方法分别模拟了光在腕部手厥阴心包经、相邻肌腱以及旁开非经络线上的光传输特性。模拟结果表明,光沿腕部手厥阴心包经呈优势传输,与本实验室之前实验所得的结果相一致。分别计算了三个模型中各层的光通量情况,计算结果表明,腕部心包经循行区域的光传输特性主要受该区域的底层结构和底层组织成分影响,光在底层结构中也是沿腕部心包经呈优势传输的,并且该优势传输的现象与腕部心包经底层的筋膜间隙结构有关。     

Multi-oriented moiré superstructures of graphene on Ir(111): experimental observations and theoretical models

Six types of moiré superstructures of graphene on Ir(111) with different orientations (labeled as R0, R14, R19, R23, R26 and R30) are investigated by low-energy electron diffraction, scanning tunneling microscopy and first-principles calculations. The moiré superstructure of R0 graphene has remarkable diffraction spots and deeper corrugation than that of the other superstructures. A high-order commensurate (HOC) method is applied to produce a list of all possible graphene moiré superstructures on Ir(111). Several useful structural data including the precise matrices of the moiré patterns are revealed. Density functional theory based first-principles calculations that include van der Waals interactions reveal the differences of the geometric environment and electronic structures of carbon atoms with respect to the underlying Ir(111) lattices for all the observed moiré patterns. The further calculations of electronic properties at the graphene-Ir interfaces show that the electron transfers for all superstructures are small and of the same order of magnitude, which demonstrates a weak interaction between graphene and the Ir(111) substrate, leading to the coexistence of multi-oriented moiré superstructures.     

Electrocoagulation of quinone pigments

Some representative quinones, viz. one naphthoquinone (plumbagin) and five anthraquinones (alizarin, purpurin, chrysazin, emodin, and anthrarufin), were subjected to electrocoagulation. It was found that the rate and extent of coagulation of these compounds appears to correlate with the number and relative position of their phenolic substituent groups, and that all of the coagulated quinones could be recovered. Attempts were then made to electrochemically isolate three quinones, namely plumbagin, morindone and erythrolaccin, from natural sources.     

A new polyoxygenated farnesylcyclohexenone from Fungus Penicillium sp.

A new polyoxygenated farnesylcyclohexenone, peniginsengin A (1), was isolated from the fermentation of Penicillium sp. YIM PH30003, an endophytic fungus associated with Panax notoginseng (Burk.) F. H. Chen. The structure was assigned based on a combination of 1 D and 2 D NMR and mass spectral data. The cytotoxicity and antimicrobial activities of compound 1 were investigated.     

Anti-phytopathogen,multi-target acetylcholinesterase inhibitory and antioxidant activities of metabolites from endophytic Chaetomium globosum

Fourteen metabolites with various structure types were isolated from endophytic Chaetomium globosum. Five compounds were separated from genus Chaetomium for the first time. Some compounds exhibited remarkable inhibition against phytopathogenic fungi causing root rot of Panax notoginseng. Compounds 1–5 had significant DPPH-free radical-scavenging activity. Compounds 3 and 5 indicated significant inhibitions against the acetylcholinesterase (AChE). From preliminary structure–activity relationship, it was found that the oxygenic five-membered ring of 3 and 5 was crucial in the anti-AChE activity. These structures provide new templates for the potential treatment and management of plant diseases and Alzheimer disease.     

旋转式硅油阻尼器动态特性实验研究

通过弹簧－质量－刚杆－阻尼器系统模拟了扭振阻尼减振系统,提出利用功率谱函数识别系统阻尼的方法,并通过有关实验对阻尼器的阻尼特性及其温度效应进行研究,最后揭示了阻尼的非线性特性。