排序方式: 共有5条查询结果,搜索用时 15 毫秒
1
1.
In many generic combustion models, one finds that a combustionwave will develop with a specific wave speed. However, thereare possible initial temperature profiles which do not evolveinto such waves, but rather die out to the ambient temperature.There can exist, in some models, a clear distinction betweenthose initial conditions that do evolve into combustion wavesand those that do not; this is sometimes referred to as thewatershed initial condition. When fuel consumption is consideredto be negligible, analytical methods can be used to obtain theexact watershed. In this paper, we consider the problem of determiningpseudo-watersheds and ascertaining the relationship betweenthese pseudo-watersheds and the exact watersheds. In the processa novel weight-function approach for infinite spatial domainsis developed. 相似文献
2.
We report herein the synthesis of cytotoxic cyanobactin, Wewakazole B through an efficient solution-phase approach. The key steps of the synthesis are the macrocyclic lactamization of linear dodecapeptide and construction of two hexapeptides with three different substituted oxazole rings. 相似文献
3.
TJ Pugh SD Weeraratne TC Archer DA Pomeranz Krummel D Auclair J Bochicchio MO Carneiro SL Carter K Cibulskis RL Erlich H Greulich MS Lawrence NJ Lennon A McKenna J Meldrim AH Ramos MG Ross C Russ E Shefler A Sivachenko B Sogoloff P Stojanov P Tamayo JP Mesirov V Amani N Teider S Sengupta JP Francois PA Northcott MD Taylor F Yu GR Crabtree AG Kautzman SB Gabriel G Getz N Jäger DT Jones P Lichter SM Pfister TM Roberts M Meyerson SL Pomeroy YJ Cho 《Nature》2012,488(7409):106-110
4.
Dr. Ahmed A. Abdelkader Dr. Dylan D. Rodene Dr. Nazgol Norouzi Dr. Ahmed Alzharani Dr. K. Shamara Weeraratne Prof. Ram B. Gupta Prof. Hani M. El-Kaderi 《Chemistry (Weinheim an der Bergstrasse, Germany)》2020,26(61):13896-13903
The rechargeable lithium-sulfur (Li-S) battery is a promising candidate for the next generation of energy storage technology, owing to the high theoretical capacity, high specific energy density, and low cost of electrode materials. The main drawbacks in the development of long-life Li-S batteries are capacity fading and the sluggish kinetics at the cathode caused by the polysulfides shuttle. These limitations are addressed through the design of novel nanocages containing cobalt phosphide (CoP) nanoparticles embedded in highly porous nitrogen-doped carbon (CoP-N-GC) by thermal annealing of ZIF-67 in a reductive atmosphere followed by a phosphidation step using sodium hypophosphite. The CoP nanoparticles, with large surface area and uniform homogeneous distribution within the N-doped nanocage graphitic carbon, act as electrocatalysts to suppress the shuttle of soluble polysulfides through strong chemical interactions and catalyze the sulfur redox. As a result, the S@CoP-N-GC electrode delivers an extremely high specific capacity of 1410 mA h g−1 at 0.1 C (1 C=1675 mA g−1) with an excellent coulombic efficiency of 99.7 %. Moreover, capacity retention from 864 to 678 mA h g−1 is obtained after 460 cycles with a very low decay rate of 0.046 % per cycle at 0.5 C. Therefore, the combination of the CoP catalyst and polar conductive porous carbon effectively stabilizes the sulfur cathode, enhancing the electrochemical performance and stability of the battery. 相似文献
5.
A. D. K. Isuri Weeraratne Chathuranga C. Hewa-Rahinduwage Sunalee Gonawala Prof. Dr. Long Luo Prof. Dr. Cláudio N. Verani 《Chemistry (Weinheim an der Bergstrasse, Germany)》2019,25(62):14048-14053
The use of metallosurfactants to prevent pitting corrosion of aluminum surfaces is discussed based on the behavior of the metallosurfactants [ZnII(LN2O2)H2O] ( 1 ) and [GaIII(LN2O3)] ( 2 ). These species were deposited as multilayer Langmuir–Blodgett films and characterized by IR reflection absorption spectroscopy and UV/Vis spectroscopy. Scanning electron microscopy images, potentiodynamic polarization experiments, and electrochemical impedance spectroscopy were used to assess corrosion mitigation. Both metallosurfactants demonstrate superior anticorrosion activity due to the presence of redox-inactive 3d10 metal ions that enhance the structural resistance of the ordered molecular films and limit chloride mobility and electron transfer. 相似文献
1