Novel, Equimolar, Multiphase CoCuNiTiV High-Entropy Alloy: Phase Component, Microstructure, and Compressive Properties

Jiaojiao Yi,Lin Yang,Lu Wang,Mingqin Xu 대한금속·재료학회 2021 METALS AND MATERIALS International Vol.27 No.7

The phase component, microstructure, and compressive properties of a novel 3d transition metal high entropy alloy, CoCuNiTiV, derived from Fe replaced by V in CoCuNiTiFe alloy, were evaluated in as-cast and annealed conditions. The experiments showed that the as-cast alloy possessed a typical BCC+FCC dual-phases, which distinctly varied from the singleFCC phase of an adjacent CoCuNiTiFe alloy. The BCC phase takes up the majority acting as the matrix, in which Cu wasdepleted, and the other elements (i.e., Co, Ni, Ti, and V) were distributed homogenously. Meanwhile, the FCC phase wasCu-rich, and sandwiched in the interval space between the BCC phases forming a net-like framework. After annealing, thematrix bifurcated into two parts: (i) one that remained as the primary BCC phase and (ii) another that decomposed into aCo2Ti-type laves phase and a new BCC phase. Meanwhile, the Cu-rich net-like framework is deteriorated forming a seriesof evenly distributed particles. The yield strength and the fracture strength of the as-cast and annealed alloy are highlysimilar— about 1674 and 2400 MPa, respectively. The hardness of the annealed alloy (572.9±10.6 HV) was slightly higherthan that of the as-cast alloy (530.3±12.2 HV).

Improvement of FK506 Production by Selection of 4-Aminobutyric Acid-tolerant Mutant and Optimization of its Fermentation Using Response Surface Methodology

Yang, Tianyi,Li, Jiaojiao,Li, Liangzhi,Zhang, Haiyang,Ma, Jing,Chen, Zhi,Hu, Cuiying,Ju, Xin,Fu, Jiaolong 한국응용생명화학회 2014 Applied Biological Chemistry (Appl Biol Chem) Vol.57 No.6

Tacrolimus (FK506), a 23-membered polyketide macrolide with immunosuppressant activity, can be produced by Streptomyces tsukubaensis. We studied a variety of mutant strains of S. tsukubaensis for the microbial production of FK506. The best strain (CZ-19) was obtained from the parent strain LLZ-1 by nitrosoguanidine mutation and 4-Aminobutyric acid (FK506 precursor structure analogs) adaption. In the shake-flask experiments, titer of FK506 by CZ-19 was 532.44 mg/L, increased by 65.13% compared to that of the parent strain. Through single factor experiments and response surface methodology, we further optimized the medium for improved FK506 production by CZ-19 in shake flask culture. The optimal medium for enhanced FK506 production was as follows: 17.19 g/L corn starch, 21.78 g/L glucose, 8.06 g/L peptone, and 18.98 mg/L 4-aminobutyric acid. The predicted FK506 titer was 906.49 mg/L, and the experimental data confirmed the validity of the model. The present study demonstrates that S. tsukubaensis CZ-19 is a promising strain for industrial production of FK506.

Lightweight, Refractory High-Entropy Alloy, CrNbTa0.25TiZr, with High Yield Strength

Jiaojiao Yi,Lin Yang,Lu Wang,Mingqin Xu 대한금속·재료학회 2022 METALS AND MATERIALS International Vol.28 No.2

A new lightweight, refractory high entropy alloy (HEA), CrNbTa0.25TiZr,was prepared by arc-melting under a vacuumcondition. The as-cast and annealed CrNbTa0.25TiZrpossessed identical dual-phase components: a BCC + a cubic Lavesphase. After annealing, the Laves phase matrix in the as-cast alloy was replaced by the BCC phase, possibly due to the diffusionof Cr, which have a much smaller atomic radius than the other principal elements. From a performance perspective,the yield strength significantly increased from 926 MPa of the as-cast HfNbTaTiZr to 1800 MPa and 1500 MPa for as-castand annealed CrNbTa0.25TiZr,while its density (7.25 g/cm3) is only 73% of HfNbTaTiZr. The microstructure evolution ofthe stiff cubic Laves phase is highlighted to unveil the promising strength of the CrNbTa0.25TiZr.

Equiatomic, Cu‐Containing CrCuFeTiV 3d Transition Metal High Entropy Alloy with an Enhanced Strength and Hardness Synergy

Jiaojiao Yi,Lin Yang,Lu Wang,Mingqin Xu,Lisha Liu 대한금속·재료학회 2022 METALS AND MATERIALS International Vol.28 No.1

A novel 3d transition metal high entropy alloy (TM HEA), CrCuFeTiV, was fabricated by arc-melting under a vacuum condition. Its phase component, microstructure, and compressive properties in the as-cast and annealed conditions were carefullyinvestigated. The experimental results showed that the alloys in both conditions consist of one BCC phase (CrV/FeTi-richregions), one FCC phase (Cu-rich), and one hexagonal Laves phase (Cr2Ti). It is suggested that the CrV-rich BCC phasepreferentially separates as dendritic centers. Subsequently, the Cr2Ti Laves phase and the FeTi-rich BCC phase solidify as adendritic outer layer. Finally, the FCC Cu-rich phase is squashed into the remaining interdendritic regions. Besides, the yieldstrength, ultimate strength, and hardness of the as-cast CrCuFeTiV alloy are 1686 MPa, 2205 MPa, and 624 HV, while thosefor the annealed alloy are 1510 MPa, 2035 MPa, and 618 HV, respectively. The obtained values are the highest among thetabulated fve-principle equiatomic Cu-containing 3d TM HEAs. The promising strength-hardness synergy of CrCuFeTiValloy is likely originated from the majority constitution of the BCC phase and Cr2Ti Laves phase.

Improvement of FK506 Production by Selection of 4-Aminobutyric Acid-tolerant Mutant and Optimization of its Fermentation Using Response Surface Methodology

Tianyi Yang,Jiaojiao Li,Liangzhi Li,Haiyang Zhang,Jing Ma,Zhi Chen,Cuiying Hu,Xin Ju,Jiaolong Fu 한국응용생명화학회 2014 Applied Biological Chemistry (Appl Biol Chem) Vol.57 No.6

Tacrolimus (FK506), a 23-membered polyketidemacrolide with immunosuppressant activity, can be produced byStreptomyces tsukubaensis. We studied a variety of mutant strainsof S. tsukubaensis for the microbial production of FK506. Thebest strain (CZ-19) was obtained from the parent strain LLZ-1 bynitrosoguanidine mutation and 4-Aminobutyric acid (FK506precursor structure analogs) adaption. In the shake-flask experiments,titer of FK506 by CZ-19 was 532.44 mg/L, increased by 65.13%compared to that of the parent strain. Through single factorexperiments and response surface methodology, we furtheroptimized the medium for improved FK506 production by CZ-19in shake flask culture. The optimal medium for enhanced FK506production was as follows: 17.19 g/L corn starch, 21.78 g/Lglucose, 8.06 g/L peptone, and 18.98 mg/L 4-aminobutyric acid. The predicted FK506 titer was 906.49 mg/L, and the experimentaldata confirmed the validity of the model. The present studydemonstrates that S. tsukubaensis CZ-19 is a promising strain forindustrial production of FK506.

Response of Photosynthetic Characteristics to Different Salicylic Acid Concentrations in Relation to Waterlogging Resistance in Zanthoxylum armatum

Peiyun Wang,Chengyi Su,Jiaojiao Wu,Yuxin Xie,Jiangtao Fan,Jingyan Wang,Wenkai Hui,Hua Yang,Wei Gong 한국원예학회 2023 원예과학기술지 Vol.41 No.4

Zanthoxylum armatum (Rutaceae) is an important spice and a traditional medicinal plant in southwest China. Owing to its shallow root system, it is highly susceptible to waterlogging stress. To evaluate how an exogenous salicylic acid (SA) application reduces photosynthetic damage in Z. armatum under waterlogging stress conditions, the content of photosynthetic pigments and gas exchange and chlorophyll fluorescence parameters were studied under different SA concentrations (0, 1 and 2 mM) and different numbers of waterlogging days (1, 2 and 3 d) to identify the mechanisms underlying the seedlings’ waterlogging response. The results showed that waterlogging significantly affects the photosynthetic characteristics in leaves. An exogenous SA application increased the contents of photosynthetic pigments as well as the transpiration rate (Tr), net leaf photosynthetic rate (Pn), stomatal conductance (Gs), water use efficiency (WUE), actual quantum efficiency (ΦPSII), photosystem II (PSII) maximum quantum efficiency (Fv/Fm), PSII photochemical efficiency in light (Fv'/Fm'), and electron transport rate (ETR), whereas the treatment decreased the intercellular carbon dioxide concentration (Ci), non-photochemical quenching coefficient (NPQ) and minimum fluorescence (Fo). Therefore, the SA application helps improve the photosynthetic efficiency and reduce photodamage to Z. armatum in the event of waterlogging stress.

Sphingomonas morindae sp. nov., isolated from Noni (Morinda citrifolia L.) branch

Yao, Su,Ge, Yuanyuan,Zhai, Lei,Liu, Yang,Su, Jiaojiao,Cao, Yanhua,Cheng, Chi,Kim, Song-Gun,Lee, Yong-Jae,Zhang, Xin Microbiology Society 2015 International journal of systematic and evolutiona Vol.65 No.9

Effect of Cr Incorporation on the Mechanical Properties of HfMoTiZrCr, HfMoNbZrCr, and HfMoNbTiCr Refractory High-Entropy Alloys

Lu Wang,Xia Li,Hongwei Niu,Lin Yang,Mingqin Xu, Jiaojiao Yi 대한금속·재료학회 2022 METALS AND MATERIALS International Vol.28 No.10

Cr was used to replace Nb, Ti, and Zr in a precursor alloy HfMoNbTiZr, and its effect on the microstructure, phase constitution,and mechanical properties of the newly formed alloys were investigated. Microstructural evolutions revealed thata cubic Laves phase emerged regardless of which element was substituted by Cr. The original single-phase BCC structureof the precursor alloy was thus deteriorated and replaced by two BCC and one cubic Laves phases. The formation of theLaves phase and BCC phases increased the strength to 2480 ± 40 MPa in the HfMoNbTiCr alloy, while the net-like structure(Laves phase) impeded the crack extension and compensated for the decreased plasticity due to the introduction of thebrittle-stiff Laves phase. The other two alloys, HfMoTiZrCr and HfMoNbZrCr, possessed lower strengths of 1400 ± 20 and1642 ± 23 MPa and exhibited a completely brittle fracture character, which was attributed to the high volume fraction andthe morphologies of the Laves phase.

基于网购背景下销售员沟通方式对融洽关系和顾客购买行为影响研究

延光豪 ( Guanghao Yan ),金华岭 ( Hualing Jin ),杨佼娇 ( Jiaojiao Yang ) 한국유통물류정책학회 2021 유통물류연구 Vol.8 No.4

1998年, 世纪互联通讯技术有限公司宣布, 中国内地第一笔互联网电子交易成功, 由此拉开了中国网购时代的帷幕。2003年, 阿里巴巴投资成立C2C网站淘宝, 在接下来的数年里, 中国的网购事业呈现出蓬勃发展的新气象。网络购物凭借其自身优势快速地抢占了大量的市场份额, 另一方面, 它也创造了前所未有的新形式的消费者问题。如, 消费者与销售员的沟通问题区别于以往传统的营销模式, 网购背景下, 顾客与销售员彼此立场不同, 所拥有的产品信息量不对等, 使得彼此之间的沟通中往往会容易产生误解与摩擦。当今市场营销的基本观念是顾客满意中心论, 销售员与顾客之间的关系理当维持着融洽关系, 而影响顾客购买行为应当成为每一个销售员的工作核心。 本文通过实证研究了解不同的沟通方式对顾客与销售员之间融洽关系的影响, 及融洽关系对提高顾客满意度的影响, 顾客满意度与其购买行为之间的关系。 In 1998, Century Internet Communication Technology Co., Ltd. announced the success of the first Internet electronic transaction in mainland China, which opened the curtain of the era of online shopping in China. In 2003, Alibaba invested in the establishment of a C2C website Taobao. In the next few years, China’s online shopping business will show a new vigorous development. Online shopping has quickly seized a large number of market shares with its own advantages. On the other hand, it has also created unprecedented new forms of consumer problems. For example, the communication between consumers and salesperson is different from the previous traditional marketing model. In the context of online shopping, customers and salesperson have different positions and unequal product information, which makes it easy to misunderstand and friction in their communication. The basic concept of today’s marketing is customer satisfaction in academic. The relationship between salesperson and customers should maintain the rapport, and the influence of purchase behavior should become the core of each salesperson’s work. In this paper, we use empirical research to understand how different communication styles will effect the rapport of customers and salesperson, the impact of rapport on improving customer satisfaction, and the relationship between customer satisfaction and purchase behavior.

An engineered PD-1-based and MMP-2/9-oriented fusion protein exerts potent antitumor effects against melanoma

( Mulan Wei ),( Xujie Liu ),( Chunyu Cao ),( Jianlin Yang ),( Yafeng Lv ),( Jiaojiao Huang ),( Yanlin Wang ),( Ye Qin ) 생화학분자생물학회(구 한국생화학분자생물학회) 2018 BMB Reports Vol.51 No.11

Recent studies showed that the PD-1/PD-L1 checkpoint blockade is a dramatic therapy for melanoma by enhancing antitumor immune activity. Currently, major strategies for the PD-1/PD-L1 blockade have mainly focused on the use of antibodies and compounds. Seeking an alternative approach, others employ endogenous proteins as blocking agents. The extracellular domain of PD-1 (ePD1) includes the binding site with PD-L1. Accordingly, we constructed a PD-1-based recombinantly tailored fusion protein (dFv-ePD1) that consists of bivalent variable fragments (dFv) of an MMP-2/9-targeted antibody and ePD1. The melanoma-binding intensity and antitumor activity were also investigated. We found the intense and selective binding capability of the protein dFv-ePD1 to human melanoma specimens was confirmed by a tissue microarray. In addition, dFv-ePD1 significantly suppressed the migration and invasion of mouse melanoma B16-F1 cells, and displayed cytotoxicity to cancer cells in vitro. Notably, dFv-ePD1 significantly inhibited the growth of mouse melanoma B16-F1 tumor cells in mice and in vivo fluorescence imaging showed that dFv-ePD was gradually accumulated into the B16-F1 tumor. Also the B16-F1 tumor fluorescence intensity at the tumor site was stronger than that of dFv. This study indicates that the recombinant protein dFv-ePD1 has an intensive melanoma-binding capability and exerts potent therapeutic efficacy against melanoma. The novel format of the PD-L1-blocked agent may play an active role in antitumor immunotherapy. [BMB Reports 2018; 51(11): 572-577]