Effect of Al on the Microstructure and Mechanical Properties of Mg–Sn–Ca–Mn Wrought Alloy

Yun Feng,Yuanyuan Yang,Zongqi Xiao,Xianglong Meng,Guorong Zhou,Jinfeng Leng,Xinying Teng 대한금속·재료학회 2022 METALS AND MATERIALS International Vol.28 No.6

Mg–Sn–Ca–Mn–xAl (x = 0,1.5 wt%) alloys with ultra-fine recrystallized grains were prepared by conventional extrusion(400 °C, 0.5 mm/s). Effects of aluminum (Al) on mechanical properties and microstructure of the Mg–1Sn–1Ca–0.5Mn(wt%) alloy were systematically investigated. By the addition of 1.5 wt% Al, the yield strength of the as-extruded alloysignificantly increased from 183 to 237 MPa. The as-cast alloys show a dendritic structure consists of α-Mg, (Mg, Al)2Ca,and CaMgSn phases. The as-extruded Mg–1Sn–1Ca–0.5Mn–1.5Al alloys exhibit a bimodal grain structure composed ofdynamic recrystallized (DRXed) fine grains and coarse unDRXed grains. Compared with Al free alloy, a lot of nano-scaleplanar Al2Caand rectangle shape Al8Mn5precipitated in the as-extruded alloy with 1.5 wt% Al. Meanwhile, the addition ofAl significantly strengthened alloys’ fiber texture with < 10–10 >//ED.

Intragranular and Intergranular Crack Propagation in Nanocrystalline Ni Under Single-Cycle Mode I Loading

Yan Feng,Jie Li,Xinhua Yang 대한금속·재료학회 2022 METALS AND MATERIALS International Vol.28 No.7

As the first step to study the fatigue crack propagation, the molecular simulations were performed to investigate theopening, propagation and closure behaviors of intragranular and intergranular cracks in nanocrystalline Ni under single-cyclemode I loading. The atomic crack angle was proposed to characterize the crack-tip blunting and sharpening quantitatively. There are obvious different mechanisms between intragranular and intergranular crack propagation. Intragranular crack propagationcould be induced by stacking faults and can change its direction very easily, but the intergranular crack perpendicularto the loading direction would propagate along the grain boundary and encounter strong resistance at the triple junction. New cracks could form in the grain boundaries ahead of the original crack. Different from the traditional understanding forintragranular and intergranular cracks, however, the dislocation density increases even in the unloading process and the cracktip is possibly sharpened temporarily during loading.

마그네슘 풍부 해양미네랄 용액이 hairless 마우스의 아토피성 피부염에 미치는 영향

김동희,이규재,최주봉,이영미,윤양숙,김정례,장병수,양용석 韓國電子顯微鏡學會 2008 Applied microscopy Vol.38 No.3

Atopic dermatitis (AD) is a chronically relapsing inflammatory skin disease that often has asthma and allergic rhinitis. Magnesium salts, the important component of minerals in Dead Sea water, are known to exhibit beneficial effects in inflammatory disease. Favorable effects of magnesium ions and sea water treated to the skin of patients with contact dermatitis have been reported. But histological and immunological investigations are insufficient. This study was performed to examine the inhibitory effect of magnesium-rich sea mineral water on the development of AD-like skin lesions in hairless mice. AD-like skin lesions are induced by the repeated application of 2,4-dinitrochlorobenzene (DNCB). Local application of magnesium-rich sea mineral water on hairless mice skin applied with DNCB inhibited the development of AD-like skin lesions as exemplified by a significant increase in skin hydration (p<0.01), and a decrease in epidermal water loss (p<0.01). Serum IgE level was also significantly decreased (p<0.01). These results suggest that magnesiumrich sea mineral water inhibits the development of DNCB-induced AD-like skin lesions in hairless mice. These observations indicate that magnesium-rich sea mineral water may be alternative and assistant substances for the management of AD. 아토피성 피부염은 주로 천식과 비염 등을 동반하는, 주위에서 흔히 볼 수 있는 만성 염증성 피부질환으로 유전학적, 환경적, 면역학적 요인이 복잡하게 연관되어 발병한다. 해수에 포함된 마그네슘염은 피부에 작용하여 피부장벽을 보호하는 것으로 알려지고 그에 대한 면역학적인 연구와 조직학적 연구는 아직 부족한 실정이다. 이번 연구에서는 피부염을 인위적으로 일으키는 hapten 형성물질인 DNCB를 hairless mice에 도포하여 아토피 피부염 동물 모델로 만든 후, 마그네슘이 다량 함유된 해양 미네랄수를 처리한 후 피부장벽에 미치는 영향을 관찰하였다. DNCB로 피부염을 유발한 hairless mice에 해양미네랄수를 국소적으로 도포하였을 때 유의한 피부수분함량이 증가와 경피수분손실의 감소를 확인하였다 (p<0.01). 피부측정에서 피부거칠기(skin roughness, p<0.05)와 스케일생성 (skin scaliness, p<0.01)은 실험군에서 유의한 개선효과를 나타내었으며 조직학적 검사에서도 피부손상지수의 유의한 감소 (p<0.01)와 비만세포와 (p<0.01) 호산구의 감소(p<0.05) 소견을 보였고 또한 혈청 IgE의 감소를 관찰할 수 있었다(p<0.01). 이상과 같이 마그네슘이 다량 함유된 해양 미네랄수 도포는 피부장벽의 손상을 줄이고 피부수분손실을 효과적으로 줄임으로 아토피성 피부염 증상 유발을 억제할수 있음을 확인하였다. 현재까지 아토피성 피부염의 관리를 위하여 세라마이드나 식물성 오일의 보습제가 주로 활용되고 있는 상황에서 부가적인 피부장벽의 보호를 위하여 탈염 해양 미네랄수의 활용이 가능할 것으로 판단되며 장기적으로 아토피 피부염치료의 대체, 혹은 보조적 물질로 활용될 수 있을 것으로 기대된다.

Conceptual Cluster-based Large-scale Ontology Compression Approach

Yang Feng,Qin Ziting 보안공학연구지원센터 2016 International Journal of Database Theory and Appli Vol.9 No.7

With the development of semantic web and ontology application, there is a large number of ontology whose scale is large and the structure is complex in different fields. The existing mapping method and mapping system perform well when dealing with the mapping between a lightweight small ontology. However, when comes to the large-scale ontology, it is full of challenges to the methods and systems。To this end, this paper proposes a method of ontology compression based on conceptual cluster to compress. Firstly, it calculates the semantic similarity and semantic correlation of ontology concepts with the DICE coefficient method and the information entropy technology to get semantic relation. Secondly according to the semantic relations, it carries on the conceptual cluster in the concept space so that the concept of semantic relations closely together in groups. The concept of cluster in space is reduced, and the "noise concept" which is independent of the mapping is removed, and the purpose of the large-scale ontology compression is realized. Experimental results show that the method is so effective that it can compress the volume of large-scale ontology in the mapping problems.

An Exploratory Study of Cyber Group Development Process

Feng Yang Kuo,Chia Ping Yu 한국경영정보학회 2001 한국경영정보학회 학술대회논문집 Vol.2001 No.-

Prevalence and Age, Gender and Geographical Area Distribution of Esophageal Squamous Cell Carcinomas in North China from 1985 to 2006

Feng, Xiao-Shan,Yang, Yan-Tong,Gao, She-Gan,Ru, Yi,Wang, Gong-Ping,Zhou, Bo,Wang, Yu-Feng,Zhang, Peng-Fei,Li, Pu-Yu,Liu, Yong-Xuan Asian Pacific Journal of Cancer Prevention 2014 Asian Pacific journal of cancer prevention Vol.15 No.5

Objective: To establish the prevalence and distribution profile of esophageal squamous cell carcinomas (ESCCs) over a 22-yr period in North China. Methods: Using endoscopy for primary diagnosis and histological analysis for the further confirmation, a total of 74,854 ESCC patients aged 20-89 between January 1985 and December 2006 were investigated to analyze the epidemiological profile including prevalence rates, distribution of age-of-onset, gender and geographical area of ESCC in Luoyang, the highest incidence area of North China. Results: A total of 4092 cases of ESCC were finally diagnosed among 74,854 patients who had their first endoscopies. The prevalence among males was higher than that among females (p<0.01), resulting in an overall male:female OR of 1.2 (95%CI, 1.2-1.3). The prevalence in rural areas was higher than in urban areas (p<0.01), resulting in an overall rural:urban OR of 2.6 (95%CI, 2.4-2.9). The rural:urban ORs and the 95% CI increased continuously from 2.6, 2.3-3.0 to 2.7, 2.2-3.3, respectively, for 4 consecutive periods during the 22-yr study period. Moreover, the median age of onset among females was higher than that among males (p<0.01). For both sexes and in both areas, the prevalence rates declined and the median age of onset rose for 4 consecutive periods in the 22-yrs time frame (p<0.01). Conculsions: These data reveal the epidemiological profile of ESCC in the area of North China, and suggest that urban areas and rural people account for a growing proportion of the ESCC patients although the prevalence of ESCC significantly declined and the median age-of-onset postponed over the 22-yrs period. Moreover, the prevalence status of ESCC in rural areas also underlines the need for public health initiatives aimed at reducing risk factors of this fatal disease.

Wireless Synchronous Transfer of Power and Reverse Signals

Yang Li,Yumei Li,Shaojie Feng,Qingxin Yang,Weihao Dong,Jingtai Zhao,Ming Xue 전력전자학회 2019 JOURNAL OF POWER ELECTRONICS Vol.19 No.3

Wireless power transfer via coupled magnetic resonances has been a hot research topic in recent years. In addition, the number of related devices has also been increasing. However, reverse signals transfer is often required in addition to wireless power transfer. The structure of the circuit for a wireless power transfer system via coupled magnetic resonances is analyzed. The advantages and disadvantages of both parallel compensation and series compensation are listed. Then the compensation characteristics of the inductor, capacitor and resistor were studied and an appropriate compensation method was selected. The reverse signals can be transferred by controlling the compensation of the resistor. In addition, it can be demodulated by extracting the change of the primary current. A 3.3 MHz resonant frequency with a 100 kHz reverse signals transfer system platform was established in the laboratory. Experimental results demonstrate that wireless power and reverse signals can be transferred synchronously.

Fluorine-Substituted Dithienylbenzodiimide-Based n-Type Polymer Semiconductors for Organic Thin-Film Transistors

Feng, Kui,Zhang, Xianhe,Wu, Ziang,Shi, Yongqiang,Su, Mengyao,Yang, Kun,Wang, Yang,Sun, Huiliang,Min, Jie,Zhang, Yujie,Cheng, Xing,Woo, Han Young,Guo, Xugang American Chemical Society 2019 ACS APPLIED MATERIALS & INTERFACES Vol.11 No.39

<P>Imide functionalization is one of the most effective approaches to develop electron-deficient building blocks for constructing n-type organic semiconductors. Driven by the attractive properties of imide-functionalized dithienylbenzodiimide (TBDI) and the promising device performance of TBDI-based polymers, a novel acceptor with increased electron affinity, fluorinated dithienylbenzodiimide (TFBDI), was designed with the hydrogen replaced by fluorine on the benzene core, and the synthetic challenges associated with this highly electron-deficient fluorinated imide building block are successfully overcome. TFBDI showed suppressed frontier molecular orbital energy levels as compared with TBDI. Copolymerizing this new electron-withdrawing TBDI with various donor co-units afforded a series of n-type polymer semiconductors TFBDI-T, TFBDI-Se, and TFBDI-BSe. All these TFBDI-based polymers exhibited a lower-lying lowest unoccupied molecular orbital (LUMO) energy level than the polymer analogue without fluorine. When applied in organic thin-film transistors, three polymers showed unipolar electron transport with large on-current/off-current ratios (<I>I</I><SUB>on</SUB>/<I>I</I><SUB>off</SUB>) of 10<SUP>5</SUP>-10<SUP>7</SUP>. Among them, the selenophene-based polymer TFBDI-Se with the deepest-positioned LUMO and optimal chain stacking exhibited the highest electron mobility of 0.30 cm<SUP>2</SUP> V<SUP>-1</SUP> s<SUP>-1</SUP>. This result demonstrates that the new TFBDI is a highly attractive electron-deficient unit for enabling n-type polymer semiconductors, and the fluorination of imide-functionalized arenes offers an effective approach to develop more electron-deficient building blocks in organic electronics.</P> [FIG OMISSION]</BR>

A Study of Web Searching Behaviors - Comparing the Effort - Accuracy Tradeoff Model with the Social Cognitive Theory

Feng Yang Kuo,Tsai Hsin Chu,Hong Ssu Hsieh 한국경영정보학회 2001 한국경영정보학회 학술대회논문집 Vol.2001 No.-

Mitochondrial citrate accumulation drives alveolar epithelial cell necroptosis in lipopolysaccharide-induced acute lung injury

Yang Hui-Hui,Jiang Hui-Ling,Tao Jia-Hao,Zhang Chen-Yu,Xiong Jian-Bing,Yang Jin-Tong,Liu Yu-Biao,Zhong Wen-Jing,Guan Xin-Xin,Duan Jia-Xi,Zhang Yan-Feng,Liu Shao-Kun,Jiang Jian-Xin,Zhou Yong,Guan Cha-Xi 생화학분자생물학회 2022 Experimental and molecular medicine Vol.54 No.-

Necroptosis is the major cause of death in alveolar epithelial cells (AECs) during acute lung injury (ALI). Here, we report a previously unrecognized mechanism for necroptosis. We found an accumulation of mitochondrial citrate (citratemt) in lipopolysaccharide (LPS)-treated AECs because of the downregulation of Idh3α and citrate carrier (CIC, also known as Slc25a1). shRNA- or inhibitor–mediated inhibition of Idh3α and Slc25a1 induced citratemt accumulation and necroptosis in vitro. Mice with AEC-specific Idh3α and Slc25a1 deficiency exhibited exacerbated lung injury and AEC necroptosis. Interestingly, the overexpression of Idh3α and Slc25a1 decreased citratemt levels and rescued AECs from necroptosis. Mechanistically, citratemt accumulation induced mitochondrial fission and excessive mitophagy in AECs. Furthermore, citratemt directly interacted with FUN14 domain-containing protein 1 (FUNDC1) and promoted the interaction of FUNDC1 with dynamin-related protein 1 (DRP1), leading to excessive mitophagy-mediated necroptosis and thereby initiating and promoting ALI. Importantly, necroptosis induced by citratemt accumulation was inhibited in FUNDC1-knockout AECs. We show that citratemt accumulation is a novel target for protection against ALI involving necroptosis.