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91.
Hanyu Huo Yue Chen Jing Luo Xiaofei Yang Xiangxin Guo Xueliang Sun 《Liver Transplantation》2019,9(17)
Solid polymer electrolytes as one of the promising solid‐state electrolytes have received extensive attention due to their excellent flexibility. However, the issues of lithium (Li) dendrite growth still hinder their practical applications in solid‐state batteries (SSBs). Herein, composite electrolytes from “ceramic‐in‐polymer” (CIP) to “polymer‐in‐ceramic” (PIC) with different sizes of garnet particles are investigated for their effectiveness in dendrite suppression. While the CIP electrolyte with 20 vol% 200 nm Li6.4La3Zr1.4Ta0.6O12 (LLZTO) particles (CIP‐200 nm) exhibits the highest ionic conductivity of 1.6 × 10?4 S cm?1 at 30 °C and excellent flexibility, the PIC electrolyte with 80 vol% 5 µm LLZTO (PIC‐5 µm) shows the highest tensile strength of 12.7 MPa. A sandwich‐type composite electrolyte (SCE) with hierarchical garnet particles (a PIC‐5 µm interlayer sandwiched between two CIP‐200 nm thin layers) is constructed to simultaneously achieve dendrite suppression and excellent interfacial contact with Li metal. The SCE enables highly stable Li plating/stripping cycling for over 400 h at 0.2 mA cm?2 at 30 °C. The LiFePO4/SCE/Li cells also demonstrate excellent cycle performance at room temperature. Fabricating sandwich‐type composite electrolytes with hierarchical filler designs can be an effective strategy to achieve dendrite‐free SSBs with high performance and high safety at room temperature. 相似文献
92.
The oxygen evolution reaction (OER) has aroused extensive interest from materials scientists in the past decade by virtue of its great significance in the energy storage/conversion systems such as water splitting, rechargeable metal–air batteries, carbon dioxide (CO2) reduction, and fuel cells. Among all the materials capable of catalyzing OER, layered double hydroxides (LDHs) stand out as one of the most effective electrocatalysts owing to their compositional and structural flexibility as well as the tenability and the simplicity of their preparation process. For this reason, numerous efforts have been dedicated to adjusting the structure, forming the well‐defined morphology, and developing the preparation methods of LDHs to promote their electrocatalytic performance. In this article, recent advances in the rational design of LDH‐based electrocatalysts toward OER are summarized. Specifically, various tactics for the synthetic methods, as well as structural and composition regulations of LDHs, are further highlighted, followed by a discussion on the influential factors for OER performance. Finally, the remaining challenges to investigate and improve the catalyzing ability of LDH electrocatalysts are stated to indicate possible future development of LDHs. 相似文献
93.
Filippo Maggi Claudia Giuliani Gelsomina Fico Massimo Ricciutelli Massimo Bramucci Luana Quassinti 《Plant biosystems》2019,153(2):325-335
Apium nodiflorum (L.) Lag. (water celery) is an hydrophytic plant forming dense submerged populations occurring along streams and rivers of Europe. In the present work we provided new insights into the phytochemistry and biology of A. nodiflorum. In particular, we studied the chemical profile of essential oil and polar extracts obtained from the flowering aerial parts of water celery growing in central Italy, together with the essential oil biological activities, namely antimicrobial, antioxidant and cytotoxicity on tumour cells. In addition, we correlated the productivity in secondary metabolites to the secreting structures through a detailed micromorphological study. The essential oil was dominated by two main chemotypes, characterized by myristicin and limonene, respectively. The oils showed significant toxicity on tumour cells, as evidenced by the MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) assay, with IC50 values in the range 3.8–15.9 μg mL?1, together with inhibitory effects on Candida albicans (inhibition zones of 10–11 mm). HPLC-MS analysis showed the caffeoylquinic acids and quercetin-3-O-glucoside as the most abundant phenolic compounds. Ducts and vittae were the principal secretory structures of vegetative (leaves and stems) and reproductive (fruits) parts, respectively, storing mainly essential oil. Results of this work provide scientific evidences for the possible valorization and exploitation of water celery. 相似文献
94.
95.
天然的间苯三酚类化合物来源广泛、结构新颖,具有多种药理活性,是目前天然药物化学的研究热点之一。本文对近十年发现的天然间苯三酚类化合物的化学结构和药理活性的研究进展做了调研和综述,以期对该类化合物进一步的研究提供参考。 相似文献
96.
The monolayer structure of pure dipalmitoylphosphatidylcholine (DPPC) and equimolar mixtures of DPPC/n-hexadecanol (C(16)OH) and DPPC/dipalmitoylglycerol (DPG) are studied by the film balance technique and grazing incidence X-ray diffraction measurements. At 20 degrees C, the binary systems exhibit complete miscibility. In contrast to pure DPPC monolayers, a condensing effect is observed in the presence of both non-phospholipid additives; but the phase transition behavior differs. The tilt angle of the hydrocarbon chains in the DPPC/C(16)OH mixture is significantly smaller than in pure DPPC monolayers. The tilt of the chains is even further reduced in the mixed monolayer of DPPC/DPG. A comparison of the three systems reveals distinct structural features such as phase state, chain tilt, and molecular area over a wide range of surface pressures. Therefore, these monolayers provide a highly suitable model to investigate the influence of structural parameters on biological processes occurring at the membrane surface, e.g. enzymatic reactions and adsorption events. 相似文献
97.
Norio Tanaka Yasushi Sasaki M. I. M. Mowjood K. B. S. N. Jinadasa Samang Homchuen 《Landscape and Ecological Engineering》2007,3(1):33-45
This study explored the effects of coastal vegetation on tsunami damage based on field observations carried out after the
Indian Ocean tsunami on 26 December 2004. Study locations covered about 250 km (19 locations) on the southern coast of Sri
Lanka and about 200 km (29 locations) on the Andaman coast of Thailand. The representative vegetation was classified into
six types according to their habitat and the stand structures of the trees. The impact of vegetation structure on drag forces
was analyzed using the observed characteristics of the tree species. The drag coefficient, including the vertical stand structures
of trees, C
d-all, and the vegetation thickness (cumulative trunk diameter of vegetation in the tsunami direction) per unit area, dN
u
(d: reference diameter of trees, N
u
: number of trees per unit area), varied greatly with the species classification. Based on the field survey and data analysis,
Rhizophora apiculata and Rhizophora mucronata (hereafter R. apiculata-type), kinds of mangroves, and Pandanus odoratissimus, a representative tree that grows in beach sand, were found to be especially effective in providing protection from tsunami
damage due to their complex aerial root structure. Two layers of vegetation in the vertical direction with P. odoratissimus and Casuarina equisetifolia and a horizontal vegetation structure of small and large diameter trees were also important for increasing drag and trapping
floating objects, broken branches, houses, and people. The vertical structure also provided an effective soft landing for
people washed up by the tsunami or for escaping when the tsunami waves hit, although its dN
u
is not large compared with R. apiculata-type and P. odoratissimus. In addition, the creeks inside mangroves and the gaps inside C. equisetifolia vegetation are assumed to be effective for retarding tsunami waves. This information should be considered in future coastal
landscape planning, rehabilitation, and coastal resource management. 相似文献
98.
99.
H Dieter Oschadleus 《Ostrich》2019,90(1):85-88
Several raptor species nest on top of large weaver nests. These weaver nests are usually sited in trees, but 11.7% of Red-billed Buffalo-Weaver Bubalornis niger and 25.7% of Sociable Weaver Philetairus socius nests occur on man-made structures. In an extensive literature search, a total of 16 raptor species were recorded as nesting on top of weaver nests. At least 10 raptor species used weaver nests built in trees. Seven raptor species used weaver nests on man-made sites and four raptor species only used weaver nests built on man-made sites. No owls have been recorded as using weaver nests on man-made sites. There are historical records of raptors nesting on top of weaver nests in trees, while nesting on top of weaver nests sited on man-made structures appears to be a more recent adaptation. Costs and benefits of nesting on man-made sites are briefly listed. Nesting on man-made sites may increase (by both weavers and raptors) and raptor researchers are encouraged to document cases of raptors nesting on weaver nests where these are placed in trees or artificial sites, so that there is a record of changes in frequency of nest site usage by raptors. 相似文献
100.