A successive ‘‘conversion-deposition” mechanism achieved by micro-crystalline Cu2O modified current collector for composite lithium anode

Yifei Cai,Bin Qin,Chun Li,Xiaoqing Si,Jian Cao,Xiaohang Zheng,LIANG QIAO,Junlei Qi 한국공업화학회 2023 Journal of Industrial and Engineering Chemistry Vol.120 No.-

Lithium (Li) metal is a promising material for high-energy–density batteries, but it is still plagued byobvious capacity degradation and low average Coulombic efficiency resulting from dendrite Li propagation. One main reason is the electro-mechanic coupled failure of plated Li on the current collector, whichcontributes to non-dense Li deposition on the anode. Transition metal oxides (TMOs) with a conversiontypemechanism have been used directly as the anode materials for lithium ion batteries, which demonstratedbetter electro-mechanical stability than metal Li. Herein, a successive ’’conversion-deposition’’mechanism is ingeniously developed to restrain the generation of dendritic Li. Specifically, a microcrystallineCu2O modified current collector was prepared, in which Li+ are sequentially inserted intoCu2O and deposited in the form of Li metal at successive low potential. A Li-Cu half-cell based on thehybrid mechanism sustains a high Coulombic efficiency of over 99.3 % in up to 800 cycles. This work ingeniouslyinhibits the generation of dendrite Li by incorporating conversion-type materials withdeposition-dissolution type metal Li, which contributes to a novel concept for the design of functionalcurrent collectors for composite Li anodes.

Few-mode fiber multi-parameter sensor with distributed temperature and strain discrimination.

Li, An,Wang, Yifei,Fang, Jian,Li, Ming-Jun,Kim, Byoung Yoon,Shieh, William Optical Society of America 2015 Optics letters Vol.40 No.7

<P>We propose a unique few-mode fiber (FMF)-based multi-parameter optical-fiber sensor for distributed measurement of temperature and strain. We launch a pump and a probe signal through specific linearly polarized modes into a FMF, and monitor the Brillouin frequency shift (BFS) in each mode. By analyzing the temperature and strain coefficients of the BFS of the two lowest order (LP(01), LP(11)) modes, discrimination of temperature and strain are successfully demonstrated, with an accuracy of 1.2C and 21.9??με.</P>

Flow-table Updating Strategy for Efficient Use of Renewable Energy in Software Defined Wireless Relay Networks

Li Li,Yifei Wei,Mei Song,Xiao-jun Wang 한국통신학회 2017 Journal of communications and networks Vol.19 No.6

Software defined networking (SDN) is revolutionizing thetelecommunication networking industry by providing flexible andefficient management. Because of energy cost and environmentalconcerns, green networking technologies are being developed to increasingenergy efficiency and making use of renewable energy, forboth wired and wireless networks. Relay nodes (RNs) are widelyused in wireless networks to increasing energy efficiency as well asthe network coverage. In this paper, we consider an SDN-enabledwireless relay network, in which the relay nodes are powered by renewableenergy. In the beginning, all the users can connect to a BSor an RN in the most energy efficient way, however, the availabilityof renewable energy is unpredictable, and users connected to anRN will have to be handed over to base stations (BSs) when there isnot enough renewable energy to power the RN. There are also occasionswhen an RN harvested more renewable energy than requiredto server the users connected to it, in these cases users connectedto BS or other RNs can be transferred to connect through this RN,otherwise the harvested surplus renewable energy will be wastedas it cannot be stored.We transform the problem of optimizing theuse of harvested renewable energy into a flow-table managementproblem. A model of harvested renewable energy available for RNsis built first, then we propose a dynamic flow-table updating strategy(DFTUS), which is driven by the availability of renewable energy,to maximize the use of the harvested renewable energy andthus minimize the use of traditional energy. DFTUS can be integratedas an application on top of an SDN controller. Simulationresults show that DFTUS can make more efficient use of renewableenergy thus make the overall relay network more energy efficientcompared with other routing strategies such as the capacity limitedstrategy (CLS) and the optimal path strategy (OPS).

Self-authorship development in Chinese college students: a grounded theory approach

Li, Yifei,Broido, Ellen M. 서울대학교 교육연구소 2021 Asia Pacific Education Review Vol.22 No.4

Chinese higher education institutions would be more efective in assisting college graduates to meet the requirements of an increasingly complex society if they had a better understanding of Chinese college student development. Self-authorship theory, which was initially developed for use in the USA, is relevant to contemporary Chinese society’s college graduate expectations. However, due to possible limitations on the application of this theory to diferent cultures, it is necessary to examine Chinese college students’ self-authorship development rather than presuming there is a similarity to US students. In this study, we used a grounded theory approach to explore the self-authorship development in Chinese college students. Using purposeful and theoretical sampling, we asked 13 junior and senior college students to share their signifcant college experiences, after which we conducted a constant comparative analysis. We found that while Chinese college students developed self-authorship during their undergraduate college years, they did not achieve full self-authorship by graduation. While the overall patterns of development in the epistemological, interpersonal, and intrapersonal domains were similar to those found in US students, there were distinctive aspects in each domain that were specifc to Chinese higher education. We used the students’ narratives on their college experiences to illustrate their journeys toward self-authorship.

Evaluation of coat color inheritance and production performance for crossbreed from Chinese indigenous Chenghua pig crossbred with Berkshire

Li Yujing,Yuan Rong,Gong Zhengyin,Zou Qin,Wang Yifei,Tang Guoqing,Zhu Li,Li Xuewei,Jiang Yanzhi 아세아·태평양축산학회 2022 Animal Bioscience Vol.35 No.10

Objective: This work was to determine coat inheritance and evaluate production performance for crossbred pigs from Berkshire×Chenghua (BC) compared with Chinese indigenous Chenghua (CH) pigs. Methods: The coat color phenotypes were recorded for more than 16,000 pigs, and the genotypes of melanocortin 1 receptor (MCIR) gene were identified by sequencing. The reproductive performance of 927 crossbred BC F4 gilts and 320 purebred CH gilts was recorded. Sixty pigs of each breed were randomly selected at approximately 60 days of age to determine growth performance during fattening period, which lasted for 150 days for BC pigs and 240 days for CH pigs. At the end of the fattening period, 30 pigs of each breed were slaughtered to determine carcass composition and meat quality. Results: The coat color of BC pigs exhibits a “dominant black” hereditary pattern, and all piglets derived from boars or sows genotyped ED1ED1 homozygous for MC1R gene showed a uniform black coat phenotype. The BC F4 gilts displayed a good reproductive performance, showing a higher litter and tear size and were heavier at farrowing litter and at weaning litter than the CH gilts, but they reached puberty later than the CH gilts. BC F4 pigs exhibited improved growth and carcass characteristics with a higher average daily live weight gain, lower feed-to-gain ratio, and higher carcass lean meat rate than CH pigs. Like CH pigs, BC F4 pigs produced superior meat-quality characteristics, showing ideal pH and meat-color values, high intramuscular fat content and water-holding capacity, and acceptable musclefiber parameters. C18:1, C16:0, C18:0, and C18:2 were the main fatty acids in M. longissimus lumborum in the two breeds, and a remarkably high polyunsaturated/saturated fatty acid ratio of ~0.39 was observed in the BC F4 pigs. Conclusion: The BC F4 pigs exhibit a uniform black coat pattern and acceptable total production performance. Objective: This work was to determine coat inheritance and evaluate production performance for crossbred pigs from Berkshire×Chenghua (BC) compared with Chinese indigenous Chenghua (CH) pigs.Methods: The coat color phenotypes were recorded for more than 16,000 pigs, and the genotypes of melanocortin 1 receptor (MCIR) gene were identified by sequencing. The reproductive performance of 927 crossbred BC F4 gilts and 320 purebred CH gilts was recorded. Sixty pigs of each breed were randomly selected at approximately 60 days of age to determine growth performance during fattening period, which lasted for 150 days for BC pigs and 240 days for CH pigs. At the end of the fattening period, 30 pigs of each breed were slaughtered to determine carcass composition and meat quality.Results: The coat color of BC pigs exhibits a “dominant black” hereditary pattern, and all piglets derived from boars or sows genotyped E^D1E^D1 homozygous for MC1R gene showed a uniform black coat phenotype. The BC F4 gilts displayed a good reproductive performance, showing a higher litter and tear size and were heavier at farrowing litter and at weaning litter than the CH gilts, but they reached puberty later than the CH gilts. BC F4 pigs exhibited improved growth and carcass characteristics with a higher average daily live weight gain, lower feed-to-gain ratio, and higher carcass lean meat rate than CH pigs. Like CH pigs, BC F4 pigs produced superior meat-quality characteristics, showing ideal pH and meat-color values, high intramuscular fat content and water-holding capacity, and acceptable musclefiber parameters. C18:1, C16:0, C18:0, and C18:2 were the main fatty acids in M. longissimus lumborum in the two breeds, and a remarkably high polyunsaturated/saturated fatty acid ratio of ~0.39 was observed in the BC F4 pigs.Conclusion: The BC F4 pigs exhibit a uniform black coat pattern and acceptable total production performance.

Energy Efficient Topology Control for Multi-Hop Relay Cellular Networks Based on Flow Management

Yifei Wei,Yongfu Hou,Li Li,Mei Song 한국통신학회 2017 Journal of communications and networks Vol.19 No.6

The rapid expansion of mobile communication networkshas led to a significant increase of energy consumption, and the energyconsumption of wireless access networks accounted for nearly90%. As an important form of the wireless access networks, multihoprelay networks have been widely deployed in the existing cellularnetworks. Consequently, improving the energy efficient ofmulti-hop relay cellular networks is crucial for communication networks. In this paper, we design an energy flow management frameworkfor multi-hop relay cellular networks, which contains routingplanning, traffic adjustment and power allocation. In orderto reduce the energy consumption and guarantee the system capacity,a heuristic algorithm is designed in this paper, which mixesthe ant colony algorithm with convex optimization theory. In orderto verify the effect of the proposed algorithm, we make numericalsimulation and compare it with other network management strategies,such as ant colony algorithm, shortest path routing strategyand greedy algorithm. Simulation results show that by our algorithm,the energy consumption can be reduced compared with theant colony algorithm, shortest path and greedy algorithm while ensuringthe demand of quality of service (QoS).

RPTOR methylation in the peripheral blood and breast cancer in the Chinese population

Yin Yifei,Lei Shuifang,Li Lixi,Yang Xiaoqin,Yin Qiming,Xu Tian,Zhou Wenjie,Li Hong,Gu Wanjian,Ma Fei,Yang Rongxi,Zhang Zhengdong 한국유전학회 2022 Genes & Genomics Vol.44 No.4

Background: Altered regulatory-associated protein of mTOR, complex 1 (RPTOR) methylation levels in peripheral blood was originally discovered as breast cancer (BC)-associated risk factor in Caucasians. Objective: To explore the relationship between RPTOR methylation and BC in the Chinese population, we conducted two independent case-control studies. Methods: Peripheral blood samples were collected from a total of 333 sporadic BC cases and 378 healthy female controls for the DNA extraction and bisulfite-specific PCR amplification. Mass spectrometry was applied to quantitatively measure the levels of methylation. The logistic regression, Spearman's rank correlation, and Non-parametric tests were used for the statistical analyses. Results: In our study, we found an association between BC and RPTOR_CpG_4 hypomethylation in the general population (per-10% of methylation, OR 1.29, P = 0.012), and a weak association between BC and RPTOR_CpG_8 hypomethylation in the women with older age (per-10% of methylation, OR 2.34, P = 0.006). We also identified age as a confounder for the change of RPTOR methylation patterns, especially at RPTOR_CpG_4, which represented differential methylation comparing age groups especially in the BC cases (age < 50 years vs age ≥ 50 years by Mann-Whitney U test, P < 0.0001 for BC cases and P = 0.079 for controls). Conclusion: Our study validated the association between hypomethylation of RPTOR and BC risk in the Chinese population also with weak effect and mostly for postmenopausal women. In addition, our findings provided novel insight for the regulation of DNA methylation upon aging or the change of hormone levels.

Multiple Tolerances and Dye Decolorization Ability of a Novel Laccase Identified from Staphylococcus Haemolyticus

Xingxing Li,Dongliang Liu,Zhaowei Wu,Dan Li,Yifei Cai,Yao Lu,Xin Zhao,Huping Xue 한국미생물·생명공학회 2020 Journal of microbiology and biotechnology Vol.30 No.4

Laccases are multicopper oxidases with important industrial value. In the study, a novel laccase gene (mco) in a Staphylococcus haemolyticus isolate is identified and heterologously expressed in Escherichia coli. Mco shares less than 40% of amino acid sequence identities with the other characterized laccases, exhibiting the maximal activity at pH 4.0 and 60oC with 2,2'-azino-bis (3- ethylbenzothiazoline-6-sulphonic acid) diammonium salt (ABTS) as a substrate. Additionally, the Mco is tolerant to a wide range of pH, heavy metal ions and many organic solvents, and it has a high decolorization capability toward textile dyes in the absence of redox mediators. The characteristics of the Mco make this laccase potentially useful for industrial applications such as textile finishing. Based on BLASTN results, mco is found to be widely distributed in both the bacterial genome and bacterial plasmids. Its potential role in oxidative defense ability of staphylococci may contribute to the bacterial colonization and survival.

Suspended membrane bioreactor with extracellular polymeric substances as reserve carbon source for low carbon to nitrogen ratio wastewater: Performance and microbial community composition

Min Li,Jun Feng Su,Yifei Li,Amjad Ali,Shu Yang,Shuai Zhang 한국화학공학회 2021 Korean Journal of Chemical Engineering Vol.38 No.9

A suspended membrane bioreactor (SMBR) was employed to treat low carbon to nitrogen (C/N) ratio wastewater. The suspended membranes amplified by Comamonas sp. YSF15 were collected to develop the SMBR, which showed excellent performance for nitrate (NO3 ) removal. The maximum nitrate removal efficiency of 95.22% was obtained at an initial nitrate concentration of 20mg L1, HRT of 6 h, and C/N=2.5 : 1 (molar ratio). In addition, the polysaccharide (PS) and protein (PN) compositions of the soluble microbial products (SMP), extracellular polymeric substances (EPS) and the Fourier transform infrared (FTIR) spectra indicated that the suspended membrane utilized its SMP and EPS as reserve C source to achieve higher denitrification performance under the low C/N ratio. With the increase of pH, the generated SMP and EPS in SMBR continued to increase. The increase in PS content was significantly greater than that of PN, thus forming a suspended membrane with a certain mechanical strength. Highthroughput sequencing data indicated that Comamonas sp. YSF15 played a key role in effective nitrate removal by SMBR. It can adapt to a nutrient-deficient environment, especially low (C/N) ratio, and greatly increase in the late operation of the reactor.

Coral‑Like NiFe2O4/C Composite as the High‑Performance Anode Material for Lithium‑Ion Batteries

Shanshan Bao,Yifei Xiao,Junfeng Li,Bo Yue,Yanjun Li,Wenxian Sun,Lei Liu,Yi Huang,Li Wang,Peicong Zhang,Xuefei Lai 대한금속·재료학회 2020 ELECTRONIC MATERIALS LETTERS Vol.16 No.3

In this work, we fabricated NiFe2O4/C composite with a coral-like structure through co-precipitation approach followed bythermal decomposition. The composite with a large surface area of 162.1 m2 g−1 and an average pore size of 11.8 nm wasobtained. The porous structure in the composite derived from oxalate can Effectively accommodate the volume changesof NiFe2O4 during the cycling processes. When used as anode materials, the initial charge and discharge capacities of thecomposite were 926.7 and 1277.7 mAh g−1 at 100 mA g−1. After 50 cycles, the reversible capacity of NiFe2O4/C could stillremain at 892.4 mAh g−1. Even at a current density of 2000 mA g−1, the reversible capacity still reached 523.3 mAh g−1. The results showed that the synergy between NiFe2O4 and carbon improved the electrochemical performance, and the porouscomposite could stabilize the structure of the electrode.