A perfluoropentane-in-water biphasic system, capable of optothermally generating microbubbles at low power, enhanced surface binding of protein by the bulk-To-surface concentration with minimal loss in its activity. &...
详细信息
We report a new technique - optothermal nanolithography - to achieve fast, on-demand and arbitrary patterning of different atomic-thin two-dimensional materials using the highly localized plasmonic heating effect. ...
详细信息
Near-infrared spectra of aqueous ethanol solutions of different concentrations and optical pathlengths were tested and compared two different types of infrared spectrometers. Optimal operating conditions and performan...
详细信息
Chain lengths have been calculated from the peak positions of the longitudinal acoustic modes (LAM) of polyethylene single crystals grown at several different temperatures. The data are consistent with other experimen...
Chain lengths have been calculated from the peak positions of the longitudinal acoustic modes (LAM) of polyethylene single crystals grown at several different temperatures. The data are consistent with other experimental results when the crystalline elastic modulus is taken to be 3.6 × 1012dyn/cm2. However, this is true only if the vibrations of the crystalline chain segments are unaffected by the presence of folds and cilia on the crystal surface. The LAMs of several crystal preparations were also deconvoluted with the first-order LAM of C94H190in order to remove instrumental broadening. The band shapes of the deconvoluted spectra are consistent with the idea that the LAM of polyethylene crystals is composed of two contributions: One due to chain stems in 110 sectors and a second due to chains in 200 sectors.
Direct methanol fuel cells (DMFC) hold distinct advantages over traditional hydrogen-based fuel cells. Their commercialization, however, has been bound by many factors - especially their suboptimal efficiency. This wo...
详细信息
Direct methanol fuel cells (DMFC) hold distinct advantages over traditional hydrogen-based fuel cells. Their commercialization, however, has been bound by many factors - especially their suboptimal efficiency. This work aims at enhancing the performance of DMFC through the use corrugated flow field plates. Our objectives are two-fold - one, to increase the power density of DMFC by corrugating flow field plates and two, to introduce Laser sintering (LS) as an efficient and robust method for the manufacture of such plates. Corrugated flow field plates with 10% more surface area as compared to a planar design were made by LS & tested in a DMFC environment. Our results show that the particle size of the material used - Graphite - has a significant effect upon the green strength of LS parts. We also report the performance of corrugated flow field plates with 10% higher surface area (as compared to planar plates), channel width and depth of 2mm and an electrode area of 5 cm2. This study is the first experimental approach to the use of indirect LS for making such fuel cell components.
Sulfide solid electrolytes(e.g.,lithium thiophosphates)have the highest room-temperature ionic conductivity(-10^(-2) S cm^(-1))among solid Li-ion conductors so far,and thus have attracted ever-increasing attention for...
详细信息
Sulfide solid electrolytes(e.g.,lithium thiophosphates)have the highest room-temperature ionic conductivity(-10^(-2) S cm^(-1))among solid Li-ion conductors so far,and thus have attracted ever-increasing attention for high energy-density and safety all-solid-state batteries(ASSBs).However,interfacial issues between sulfide electrolytes and electrodes have been the main challenges for their applications in *** interfacial instabilities would occur due to side reactions of sulfides with electrodes,poor solid-solid contact,and lithium dendrites during charge/discharge *** this review,we analyze the interfacial issues in ASSBs based on sulfide electrolytes,and in particular,discuss strategies for solving these interfacial issues and stabilize the electrode-electrolyte ***,a perspective of the interfacial engineering for sulfide-based ASSBs is provided.
To develop a better understanding of the capacity fading mechanisms of spinel lithium manganese oxide cathodes, the % capacity fade of a number of singly substituted LiMn2-yMyO4 (M = Li, Al, Ti, Co, Ni, and Cu and 0 &...
详细信息
To develop a better understanding of the capacity fading mechanisms of spinel lithium manganese oxide cathodes, the % capacity fade of a number of singly substituted LiMn2-yMyO4 (M = Li, Al, Ti, Co, Ni, and Cu and 0 &le y &le 0.2) and doubly substituted LiMn 2-y-zMyLizO4 (M = Al, Ti, Fe, Co, Ni, Cu, and Ga, 0 &le y &le 0.1, and 0 &le z &le 0.1) oxides is correlated to several sample characteristics: initial lattice parameter, initial manganese valence, degree of manganese dissolution, irreversible capacity (IRC) loss in the first cycle, and lattice parameter difference Δa between the two cubic phases formed in the two-phase region during cycling. While the capacity fade does not show a clear relationship to the amount of manganese dissolution, the samples exhibiting good capacity retention are characterized by a high initial Mn valence of > 3.58+, and low initial lattice parameter a, IRC, and Δa. The low Δa minimizes the microstrain and leads to a maintenance of good crystallinity with sharp diffraction peaks on cycling. The doubly substituted LiMn2-y-zNiyLizO4 samples, for example, satisfy these criteria and exhibit a combination of superior capacity retention, rate capability, and storage characteristics with low IRC compared to LiMn2O4 despite a similar amount of Mn dissolution.
暂无评论