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51.
Jung Dong-Hyun Seo Dong-Ho Kim Ga-Young Nam Young-Do Song Eun-Ji Yoon Shawn Park Cheon-Seok 《Applied microbiology and biotechnology》2018,102(11):4927-4936
Applied Microbiology and Biotechnology - Resistant starch (RS) in the diet reaches the large intestine without degradation, where it is decomposed by the commensal microbiota. The fermentation of... 相似文献
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脱氧核糖核酸(Deoxyribonucleic Acid, DNA)是一种天然的信息存储介质,具有存储密度高、存储时间长、损耗率低等特点。在传统存储方式不能满足信息增长的需求时,DNA数据存储技术逐渐成为研究热点。DNA编码是用尽可能少的碱基序列无错的存储数据信息,包括压缩(尽可能少的占用空间)、纠错(无错存储)和转换(数字信息转为碱基序列)3部分。DNA编码是DNA存储中的关键技术,它的结果直接影响存储性能的优劣和数据读写的完整。本文首先介绍DNA存储的发展历史,然后介绍DNA存储的框架,其中重点介绍DNA编码技术,最后对DNA存储中的编解码技术的未来发展方向进行讨论。 相似文献
54.
Hong‐Joon Yoon Minki Kang Wanchul Seung Sung Soo Kwak Jihye Kim Hyoung Taek Kim Sang‐Woo Kim 《Liver Transplantation》2020,10(25)
Direct conversion of mechanical energy into direct current (DC) by triboelectric nanogenerators (TENGs) is one of the desired features in terms of energy conversion efficiency. Although promising applications have been reported using the triboelectric effect, effective DC generating TENGs must be developed for practical purposes. Here, it is reported that continuous DC generation within a TENG itself, without any circuitry, can be achieved by triggering air breakdown via triboelectrification. It is demonstrated that DC generation occurs in combination with i) charge accumulation to generate air breakdown, ii) incident discharge (microdischarge), and iii) conveyance of charges to make the device sustainable. 10.5 mA m?2 of output current and 10.6 W m?2 of output power at 33 MΩ load resistance are achieved. Compared to the best DC generating TENGs ever reported, the TENG in this present study generates about 20 times larger root‐mean square current density. 相似文献
55.
Li[Ni0.9Co0.1]O2 (NC90), Li[Ni0.9Co0.05Mn0.05]O2 (NCM90), and Li[Ni0.9Mn0.1]O2 (NM90) cathodes are synthesized for the development of a Co‐free high‐energy‐density cathode. NM90 maintains better cycling stability than the two Co‐containing cathodes, particularly under harsh cycling conditions (a discharge capacity of 236 mAh g?1 with a capacity retention of 88% when cycled at 4.4 V under 30 °C and 93% retention when cycled at 4.3 V under 60 °C after 100 cycles). The reason for the enhanced stability is mainly the ability of NM90 to absorb the strain associated with the abrupt anisotropic lattice contraction/extraction and to suppress the formation of microcracks, in addition to enhanced chemical stability from the increased presence of stable Mn4+. Although the absence of Co deteriorates the rate capability, this can be overcome as the rate capability of the NM90 approaches that of the NCM90 when cycled at 60 °C. The long‐term cycling stability of NM90 is confirmed in a full cell, demonstrating that it is one of the most promising Co‐free cathodes for high‐energy‐density applications. This study not only provides insight into redefining the role of Mn in a Ni‐rich cathode, it also represents a clear breakthrough in achieving a commercially viable Co‐free Ni‐rich layered cathode. 相似文献
56.
Joonam Park Kyu Tae Kim Dae Yang Oh Dahee Jin Dohwan Kim Yoon Seok Jung Yong Min Lee 《Liver Transplantation》2020,10(35)
The digital twin technique has been broadly utilized to efficiently and effectively predict the performance and problems associated with real objects via a virtual replica. However, the digitalization of twin electrochemical systems has not been achieved thus far, owing to the large amount of required calculations of numerous and complex differential equations in multiple dimensions. Nevertheless, with the help of continuous progress in hardware and software technologies, the fabrication of a digital twin‐driven electrochemical system and its effective utilization have become a possibility. Herein, a digital twin‐driven all‐solid‐state battery with a solid sulfide electrolyte is built based on a voxel‐based microstructure. Its validity is verified using experimental data, such as effective electronic/ionic conductivities and electrochemical performance, for LiNi0.70Co0.15Mn0.15O2 composite electrodes employing Li6PS5Cl. The fundamental performance of the all‐solid‐state battery is scrutinized by analyzing simulated physical and electrochemical behaviors in terms of mass transport and interfacial electrochemical reaction kinetics. The digital twin model herein reveals valuable but experimentally inaccessible time‐ and space‐resolved information including dead particles, specific contact area, and charge distribution in the 3D domain. Thus, this new computational model is bound to rapidly improve the all‐solid‐state battery technology by saving the research resources and providing valuable insights. 相似文献
57.
Ju‐Myung Kim Jae‐Ho Park Eunmi Jo Hyung‐Seok Kim Seung‐Hyeok Kim Wonyoung Chang Kyung Yoon Chung Sang‐Young Lee 《Liver Transplantation》2020,10(9)
Despite their exceptionally high capacity, overlithiated layered oxides (OLO) have not yet been practically used in lithium‐ion battery cathodes due to necessary toxic/complex chemical activation processes and unsatisfactory electrochemical reliability. Here, a new class of ecofriendly chemical activation strategy based on amphiphilic deoxyribose nucleic acid (DNA)‐wrapped multiwalled carbon nanotubes (MWCNT) is demonstrated. Hydrophobic aromatic bases of DNA have a good affinity for MWCNT via noncovalent π–π stacking interactions, resulting in core (MWCNT)‐shell (DNA) hybrids (i.e., DNA@MWCNT) featuring the predominant presence of hydrophilic phosphate groups (coupled with Na+) in their outmost layers. Such spatially rearranged Na+–phosphate complexes of the DNA@MWCNT efficiently extract Li+ from monoclinic Li2MnO3 of the OLO through cation exchange reaction of Na+–Li+, thereby forming Li4Mn5O12‐type spinel nanolayers on the OLO surface. The newly formed spinel nanolayers play a crucial role in improving the structural stability of the OLO and suppressing interfacial side reactions with liquid electrolytes, eventually providing significant improvements in the charge/discharge kinetics, cyclability, and thermal stability. This beneficial effect of the DNA@MWCNT‐mediated chemical activation is comprehensively elucidated by an in‐depth structural/electrochemical characterization. 相似文献
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59.
Yong Jun Gong Jung Woon Heo Hakji Lee Hyunjin Kim Jinil Cho Seonmi Pyo Heejun Yun Heebae Kim Sang Yoon Park Jeeyoung Yoo Youn Sang Kim 《Liver Transplantation》2020,10(27)
Li metal, which has a high theoretical specific capacity and low redox potential, is considered to the most promising anode material for next‐generation Li ion‐based batteries. However, it also exhibits a disadvantageous solid electrolyte interphase (SEI) layer problem that needs to be resolved. Herein, an advanced separator composed of reduced graphene oxide fiber attached to aramid paper (rGOF‐A) is introduced. When rGOF‐A is applied, F? anions, generated from the decomposition of the LiPF6 electrolyte during the SEI layer formation process form semi‐ionic C? F bonds along the surface of rGOF. As Li+ ions are plated, the “F‐doped” rGO surface induces the formation of LiF, which is known as a component of a chemically stable SEI, therefore it helps the Li metal anode to operate stably at a high current of 20 mA cm?2 with a high capacity of 20 mAh cm?2. The proposed rGOF‐A separator successfully achieves a stable SEI layer that could resolve the interfacial issues of the Li metal anode. 相似文献
60.
Hoon‐Hee Ryu Nam‐Yung Park Dae Ro Yoon Un‐Hyuck Kim Chong S. Yoon Yang‐Kook Sun 《Liver Transplantation》2020,10(25)
A new class of layered cathodes, Li[NixCoyB1?x?y]O2 (NCB), is synthesized. The proposed NCB cathodes have a unique microstructure in which elongated primary particles are tightly packed into spherical secondary particles. The cathodes also exhibit a strong crystallographic texture in which the a–b layer planes are aligned along the radial direction, facilitating Li migration. The microstructure, which effectively suppresses the formation of microcracks, improves the cycling stability of the NCB cathodes. The NCB cathode with 1.5 mol% B delivers a discharge capacity of 234 mAh g?1 at 0.1 C and retains 91.2% of its initial capacity after 100 cycles (compared to values of 229 mAh g?1 at 0.1 C and 78.8% for pristine Li[Ni0.9Co0.1]O2). This study shows the importance of controlling the microstructure to obtain the required cycling stability, especially for Ni‐rich layered cathodes, where the main cause of capacity fading is related to mechanical strain in their charged state. 相似文献