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排序方式: 共有594条查询结果,搜索用时 218 毫秒
1.
Rechargeable graphite dual‐ion batteries (GDIBs) have attracted the attention of electrochemists and material scientists in recent years due to their low cost and high‐performance metrics, such as high power density (≈3–175 kW kg?1), energy efficiency (≈80–90%), long cycling life, and high energy density (up to 200 Wh kg?1), suited for grid‐level stationary storage of electricity. The key feature of GDIBs is the exploitation of the reversible oxidation of the graphite network with concomitant and highly efficient intercalation/deintercalation of bulky anionic species between graphene layers. In this review, historical and current research aspects of GDIBs are discussed, along with key challenges in their development and practical deployment. Specific emphasis is given to the operational mechanism of GDIBs and to unbiased and correct reporting of theoretical cell‐level energy densities. 相似文献
2.
The variability of the cardiac rhythm was studied in males with different initial respiratory rates. At rest and during voluntarily controlled breathing, subjects with medium respiratory rates were found to have a less variable heart rate than their counterparts with low or high respiratory rates. 相似文献
3.
G. N. Borisyuk R. M. Borisyuk A. B. Kirillov E. I. Kovalenko V. I. Kryukov 《Biological cybernetics》1985,52(5):301-306
A new method is proposed to analyse dependencies in point processes, which takes into account specific character of neuronal activity. Simulation modelling of neuronal network revealed that the estimated weight of connection depends monotonically on the value of the model synaptic strength. In contrast to the crosscorrelation, the method allows for nonlinear interconnections and does not require point processes to be stationary and samples to be large. Examples are presented of the method's application to neurophysiological data analysis. 相似文献
4.
A B Maslennikov S P Kovalenko E A Oteva T A Filimonova N P Mertvetsov 《Genetika》1991,27(12):2152-2156
Restriction fragments' length polymorphism in the region of apolipoprotein A-I (apo A-I) gene was investigated in Novosibirsk (Siberia, USSR) population. Correlation between PstI apo A-I alleles (2,2 kb-P1; 3,3 kb-P2) and total cholesterol, triglycerides, high density polyproteins cholesterol, and apolipoprotein A-I level was analysed. A tendency to increase in cholesterol index of atherogenicity and to decrease in high density lipoproteins cholesterol as well as apolipoprotein A-I level was shown to occur for P1P2 genotype patients. 相似文献
5.
6.
Lactic bacteria predominate in the microflora of the digestive tract of chicken and turkey. They are represented mainly by Lactobacillus acidophilus, L. salivarius, L. fermentum and L. buchneri. Streptococcus faecium is always isolated. L. ruminis, L. vitulinus, L. delbrueckii, L. coryniformis and L. viridescens were found in this ecological niche for the first time. S. faecium and S. faecalis prevail in the digestive tract of geese and ducks, while lactobacilli are detected in a lesser amount and are represented mainly by L. plantarum. L. salivarius cells isolated from the digestive tract of poultry are highly polymorphous. Most of the lactic acid bacteria found in the digestive tract of poultry can grow at 45-50 degrees C whatever is the species they belong to. 相似文献
7.
O A Kovalenko N I Tarasova A G Ivannikova L N Voronkova T G Nikolaeva 《Tsitologiia》1989,31(4):447-452
The effect of picolinic acid (PA) on SPEV cell proliferation is found to be different from that on normal and virus transformed NRC cells, and on spontaneously transformed CHO cells. It is shown that SPEV cells are arrested by PA at the end of G1-phase and at the beginning of S-phase and probably in G2-phase of the cell cycle. Ferrous ions remove the G1/S block induced by PA to permit the cell transfer through S-phase. On the one hand, PA chelates ferrous ions from the cells, and on the other one it inhibits the replicative DNA synthesis. It can be suggested that PA may arrest the SPEV cell growth affecting the iron-depend stable radical formation which is introduced into the active centre of ribonucleotiDE reduCTase. This results in the lower enzyme activity. 相似文献
8.
E A Kovalenko N V Koltukova T V Strel'china 《Prikladnaia biokhimiia i mikrobiologiia》1990,26(4):528-533
The dynamics of the consumption of major carbon and nitrogen sources and the biosynthesis of hydrolytic enzymes were studied in Bacillus mesentericus grown on semisynthetic media. Conditions were chosen that provide the obtaining of the culture liquid with predominantly proteolytic or amylolytic activity. The replacement of maltose with native starch resulted in more intensive accumulation of the biomass and hydrolytic enzymes, and in more rapid (by 3-5 hr) transformation from the logarithmic to the stationary growth phase. 相似文献
9.
S P Kovalenko V V Gorn V A Karginov I V Morozov V F Zarytova 《Bioorganicheskaia khimiia》1988,14(7):910-915
The nucleotide sequence coding for human angiogenin has been deduced from the published amino acid sequence with the use of codons preferentially utilized in highly expressed E. coli genes. It was divided into forty-three oligonucleotides, which were synthesized by automatic gene assembler and then joined by DNA ligase into three double-stranded blocks, the blocks were consequently cloned and ligated in M13mp8 phage, and the resultant 389-bp DNA sequence coding for human angiogenin was analysed by chain-terminator sequencing technique. 相似文献
10.
S. N. Kovalenko S. G. Stepanian V. P. Chuev M. M. Asimov V. M. Nikitchenko V. P. Chernykh 《Molecular Engineering》1992,2(2):153-163
In order to improve the generating and photochemical properties of coumarin laser dyes, the following active media were synthesized: inclusion complexes of -cyclodextrin (-CD) and 7-amino-4-methylcoumarins (COU1, COU102, COU120). Complex formation processes were studied, and the structure of the inclusion complexes was estimated using the method of MM2 molecular mechanics. The data obtained suggest the reasons underlying the complex structure effects on their spectral, luminescent and generating characteristics. 相似文献