In order to employ Li-ion batteries (LIBs) in next-generation hybrid electric and/or plug-in hybrid electric vehicles (HEVs and PHEVs), LIBs must satisfy many requirements: electrodes with long lifetimes (fabricated from inexpensive environmentally benign materials), stability over a wide temperature range, high energy density, and high rate capability. Establishing long-term durability while operating at realistic temperatures (5000 charge-depleting cycles, 15 year calendar life, and a range from À46 8C to þ66 8C) for a battery that does not fail catastrophically remains a significant challenge. [1] Recently, surface modifications of electrode materials have been explored as viable paths to improve the performance of LIBs for vehicular applications.[2] The cycle life and safety issues have been largely satisfied for Li x MO 2 (M ¼ Co, Ni, Mn, etc.) cathodes by coating the active material particles with a metal oxide and/or metal phosphate. [2a,2b,3] For anode, state-of-the-art materials such as Si suffer from significant volume expansion/contraction during charge-discharge leading to rapid capacity fade.[4] Natural graphite (NG) is a realistic candidate anode, for vehicular applications, due to its high reversible capacity, low and flat potential relative to Li/Li þ , moderate volume change, and low cost.[5] In previous reports, the performance of NG was improved by surface modifications with mild oxidation, [6] coating with amorphous carbon,[5c] metal oxides (Al 2 O 3 , ZrO 2 ), [5a,7] and metal phosphate (AlPO 4 ).[5b] These efforts were performed in order to mitigate the solid electrolyte interphase (SEI) [8] that is formed on the NG surface by reductive decomposition of the electrolyte during initial charge-discharge especially at elevated temperatures. The decomposition of the SEI at elevated temperature ($80 8C) is exothermic and initiates thermal runaway. [9] In most previous reports films of metal oxides and metal phosphates have been deposited on powder electrode materials with 'sol-gel' wet-chemical methods.

To deploy Li-ion batteries in next-generation vehicles, it is essential to develop electrodes with durability, high energy density, and high power. Here we report a breakthrough in controlled full-electrode nanoscale coatings that enables nanosized materials to cycle with durable high energy and remarkable rate performance. The nanoparticle electrodes are coated with Al(2)O(3) using atomic layer deposition (ALD). The coated nano-LiCoO(2) electrodes with 2 ALD cycles deliver a discharge capacity of 133 mAh/g with currents of 1400 mA/g (7.8C), corresponding to a 250% improvement in reversible capacity compared to bare nanoparticles (br-nLCO), when cycled at this high rate. The simple ALD process is broadly applicable and provides new opportunities for the battery industry to design other novel nanostructured electrodes that are highly durable even while cycling at high rate.

Ultrathin atomic layer deposition (ALD) coatings enhance the performance of lithium-ion batteries (LIBs). Previous studies have demonstrated that LiCoO2 cathode powders coated with metal oxides with thicknesses of ∼100 to 1000Å grown using wet chemical techniques improved LIB performance. In this study, LiCoO2 powders were coated with conformal Al2normalO3 ALD films with thicknesses of only ∼3 to 4Å established using two ALD cycles. The coated LiCoO2 powders exhibited a capacity retention of 89% after 120 charge–discharge cycles in the 3.3–4.5 V (vs Li/Li+ ) range. In contrast, the bare LiCoO2 powders displayed only a 45% capacity retention. Al2normalO3 ALD films coated directly on the composite electrode also produced improved capacity retention. This dramatic improvement may result from the ultrathin Al2normalO3 ALD film acting to minimize Co dissolution or reduce surface electrolyte reactions. Similar experiments with ultrathin ZnO ALD films did not display enhanced performance.

Kimchi, a traditional food in the Korean culture, is made from vegetables by fermentation. In this study, metagenomic approaches were used to monitor changes in bacterial populations, metabolic potential, and overall genetic features of the microbial community during the 29-day fermentation process. Metagenomic DNA was extracted from kimchi samples obtained periodically and was sequenced using a 454 GS FLX Titanium system, which yielded a total of 701,556 reads, with an average read length of 438 bp. Phylogenetic analysis based on 16S rRNA genes from the metagenome indicated that the kimchi microbiome was dominated by members of three genera: Leuconostoc, Lactobacillus, and Weissella. Assignment of metagenomic sequences to SEED categories of the Metagenome Rapid Annotation using Subsystem Technology (MG-RAST) server revealed a genetic profile characteristic of heterotrophic lactic acid fermentation of carbohydrates, which was supported by the detection of mannitol, lactate, acetate, and ethanol as fermentation products. When the metagenomic reads were mapped onto the database of completed genomes, the Leuconostoc mesenteroides subsp. mesenteroides ATCC 8293 and Lactobacillus sakei subsp. sakei 23K genomes were highly represented. These same two genera were confirmed to be important in kimchi fermentation when the majority of kimchi metagenomic sequences showed very high identity to Leuconostoc mesenteroides and Lactobacillus genes. Besides microbial genome sequences, a surprisingly large number of phage DNA sequences were identified from the cellular fractions, possibly indicating that a high proportion of cells were infected by bacteriophages during fermentation. Overall, these results provide insights into the kimchi microbial community and also shed light on fermentation processes carried out broadly by complex microbial communities.

Kimchi, a traditional Korean food made by the fermentation of vegetables, has become popular globally because of its organoleptic, beneficial, and nutritional properties. Spontaneous kimchi fermentation in unsterilized raw materials leads to the growth of various lactic acid bacteria (LAB), which results in variations in the taste and sensory qualities of kimchi products and difficulties in the standardized industrial production of kimchi. Raw materials, kimchi varieties, ingredients, and fermentation conditions have significant effects on the microbial communities and fermentative characteristics of kimchi during fermentation. Heterofermentative LAB belonging to the genera Leuconostoc, Lactobacillus, and Weissella are likely to be key players in kimchi fermentation and have been subjected to genomic and functional studies to gain a better understanding of the fermentation process and beneficial effects of kimchi. The use of starter cultures has been considered for the industrial production of high quality, standardized kimchi. Here, we review the composition and biochemistry of kimchi microflora communities, functional and genomic studies of kimchi LAB, and perspectives for industrial kimchi production.

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Atomic layer deposition (ALD) of Al 2 O 3 is applied on a polypropylene separator for lithium-ion batteries. A thin Al 2 O 3 layer ( < 10 nm) is coated on every surface of the porous polymer microframework without signifi cantly increasing the total separator thickness. The thin Al 2 O 3 ALD coating results in signifi cantly suppressed thermal shrinkage, which may lead to improved safety of the batteries. More importantly, the wettability of Al 2 O 3 ALD-coated separators in an extremely polar electrolyte based on pure propylene carbonate (PC) solvent is demonstrated, without any decrease in electrochemical performances such as capacity, rate capability, and cycle life. Finally, a LiCoO 2 /natural graphite full cell is demonstrated under extremely severe conditions (pure PC-based electrolyte and high (4.5 V) upper cut-off potential), which is enabled by the Al 2 O 3 ALD coating on all three components (cathode, anode, and separator).

Higher abundances of Streptophyta, Corynebacterium, and Enhydrobacter in blepharitis subjects suggested that human blepharitis might be induced by the infestations of pollens, dusts, and soil particles. These results will provide valuable information for the prevention and treatment of human blepharitis based on ocular microbial flora.