Microstructural Stability and Creep Performance of a Novel Low-Cost Single Crystal Superalloy

Z. H. Tan,X. G. Wang,Y. L. Du,Y. M. Li,Y. H. Yang,J. L. Liu,J. D. Liu,J. G. Li,Y. Z. Zhou,X. F. Sun 대한금속·재료학회 2022 METALS AND MATERIALS International Vol.28 No.7

The increasing pursuit of advanced aero-engines with lower ratio between the cost and performance has greatly promotedthe demanding of single crystal superalloys characterized by low cost and outstanding temperature capability. In this study,a novel low-cost single crystal superalloy was designed and the creep tests as well as micro-characterization were carried outon the experimental alloy. The results illustrated that the novel single crystal alloy exhibited an ideal microstructural stabilitywithout precipitating TCP phases, after long-term thermal exposure at the ultimate service temperature of third generationsingle crystal superalloys. Moreover, the experimental alloy with only 3 wt% Re addition demonstrated remarkable creepresistance and maintained a very low minimum creep rate at 1100 °C/137 MPa and 1120 °C/137 MPa, while the accumulationand coalescence of micro-pores had eventually led to the alloy fracture. Apart from that, the compact interfacial dislocationnetworks the 2nd γ′ phase were observed after high-temperature creep rupture, and the typical a < 010 > superdislocationswith relatively poor mobility was found at 1120 °C. At 760 °C/800 MPa, both the minimum creep velocity and entire creepstain was increased evidently, however, the ultimate creep rupture life of the alloy had still reached 200 h. The correspondingdeformation mechanism was identified as the combination of superdislocation pairs shearing and a/3 < 121 > partial dislocationcutting the γ′ phase with a SISF being generated. In general, the novel single crystal alloy characterized by remarkablemechanical properties and cost reduction possesses a great potential for future application in the advanced aircraft engines.

A novel design method for improving collapse resistances of multi-story steel frames with unequal spans using steel braces

Zheng Tan,Wei-hui Zhong,Bao Meng,Shi-chao Duan,Hong-chen Wang3,Xing-You Yao,Yu-hui Zheng 국제구조공학회 2023 Steel and Composite Structures, An International J Vol.47 No.2

The bearing capacities resisted by the two-bay beams of multi-story planar frames with unequal spans under column removal scenarios differ considerably owing to the asymmetric stress on the left and right beams connected to the failed column and cause the potential for beams with larger span-to-depth ratios to be unable to exert effectively, which is disadvantageous for resisting the vertical load in unequal-span frame structures. To address this problem, the structural measure of adding braces to the weak bays of multi-story unequal-span frames was proposed, with the objective of achieving a coordinated stress state in two-bay beams with unequal spans, thereby improving the collapse resistance of unequal-span frame structures. Before conducting the numerical simulation, the modeling methods were verified by previous experimental results of two multi-story planar frames with and without steel braces. Thereafter, the effects of the tensile and compressive braces on the collapse behavior of the frame structures were elucidated. Then, based on the mechanical action laws of the braces throughout the collapse process, a detailed design method for improving the collapse resistance of unequal-span frame structures was proposed. Finally, the proposed design method was verified by using sufficient example models, and the results demonstrated that the design method has good application prospects and high practical value.

Tanshinone IIA Protects Endothelial Cells from H₂O₂-Induced Injuries via PXR Activation

Zhu, Haiyan,Chen, Zhiwu,Ma, Zengchun,Tan, Hongling,Xiao, Chengrong,Tang, Xianglin,Zhang, Boli,Wang, Yuguang,Gao, Yue The Korean Society of Applied Pharmacology 2017 Biomolecules & Therapeutics(구 응용약물학회지) Vol.25 No.6

Tanshinone IIA (Tan IIA) is a pharmacologically active substance extracted from the rhizome of Salvia miltiorrhiza Bunge (also known as the Chinese herb Danshen), and is widely used to treat atherosclerosis. The pregnane X receptor (PXR) is a nuclear receptor that is a key regulator of xenobiotic and endobiotic detoxification. Tan IIA is an efficacious PXR agonist that has a potential protective effect on endothelial injuries induced by xenobiotics and endobiotics via PXR activation. Previously numerous studies have demonstrated the possible effects of Tan IIA on human umbilical vein endothelial cells, but the further mechanism for its exerts the protective effect is not well established. To study the protective effects of Tan IIA against hydrogen peroxide ($H_2O_2$) in human umbilical vein endothelial cells (HUVECs), we pretreated cells with or without different concentrations of Tan IIA for 24 h, then exposed the cells to $400{\mu}M$ $H_2O_2$ for another 3 h. Therefore, our data strongly suggests that Tan IIA may lead to increased regeneration of glutathione (GSH) from the glutathione disulfide (GSSG) produced during the GSH peroxidase-catalyzed decomposition of $H_2O_2$ in HUVECs, and the PXR plays a significant role in this process. Tan IIA may also exert protective effects against $H_2O_2$-induced apoptosis through the mitochondrial apoptosis pathway associated with the participation of PXR. Tan IIA protected HUVECs from inflammatory mediators triggered by $H_2O_2$ via PXR activation. In conclusion, Tan IIA protected HUVECs against $H_2O_2$-induced cell injury through PXR-dependent mechanisms.

Tanshinone IIA Protects Endothelial Cells from H2O2-Induced Injuries via PXR Activation

Haiyan Zhu,Zhiwu Chen,Zengchun Ma,Hongling Tan,Chengrong Xiao,Xianglin Tang,Boli Zhang,Yuguang Wang,Yue Gao 한국응용약물학회 2017 Biomolecules & Therapeutics(구 응용약물학회지) Vol.25 No.6

Tanshinone IIA (Tan IIA) is a pharmacologically active substance extracted from the rhizome of Salvia miltiorrhiza Bunge (also known as the Chinese herb Danshen), and is widely used to treat atherosclerosis. The pregnane X receptor (PXR) is a nuclear receptor that is a key regulator of xenobiotic and endobiotic detoxification. Tan IIA is an efficacious PXR agonist that has a potential protective effect on endothelial injuries induced by xenobiotics and endobiotics via PXR activation. Previously numerous studies have demonstrated the possible effects of Tan IIA on human umbilical vein endothelial cells, but the further mechanism for its exerts the protective effect is not well established. To study the protective effects of Tan IIA against hydrogen peroxide (H2O2) in human umbilical vein endothelial cells (HUVECs), we pretreated cells with or without different concentrations of Tan IIA for 24 h, then exposed the cells to 400 μM H2O2 for another 3 h. Therefore, our data strongly suggests that Tan IIA may lead to increased regeneration of glutathione (GSH) from the glutathione disulfide (GSSG) produced during the GSH peroxidase-catalyzed decomposition of H2O2 in HUVECs, and the PXR plays a significant role in this process. Tan IIA may also exert protective effects against H2O2-induced apoptosis through the mitochondrial apoptosis pathway associated with the participation of PXR. Tan IIA protected HUVECs from inflammatory mediators triggered by H2O2 via PXR activation. In conclusion, Tan IIA protected HUVECs against H2O2-induced cell injury through PXR-dependent mechanisms.

Tanshinone IIA Protects Endothelial Cells from H₂O₂-Induced Injuries via PXR Activation

( Haiyan Zhu ),( Zhiwu Chen ),( Zengchun Ma ),( Hongling Tan ),( Chengrong Xiao ),( Xianglin Tang ),( Boli Zhang ),( Yuguang Wang ),( Yue Gao ) 한국응용약물학회 2017 Biomolecules & Therapeutics(구 응용약물학회지) Vol.25 No.6

Tanshinone IIA (Tan IIA) is a pharmacologically active substance extracted from the rhizome of Salvia miltiorrhiza Bunge (also known as the Chinese herb Danshen), and is widely used to treat atherosclerosis. The pregnane X receptor (PXR) is a nuclear receptor that is a key regulator of xenobiotic and endobiotic detoxification. Tan IIA is an efficacious PXR agonist that has a potential protective effect on endothelial injuries induced by xenobiotics and endobiotics via PXR activation. Previously numerous studies have demonstrated the possible effects of Tan IIA on human umbilical vein endothelial cells, but the further mechanism for its exerts the protective effect is not well established. To study the protective effects of Tan IIA against hydrogen peroxide (H₂O₂) in human umbilical vein endothelial cells (HUVECs), we pretreated cells with or without different concentrations of Tan IIA for 24 h, then exposed the cells to 400 μM H₂O₂ for another 3 h. Therefore, our data strongly suggests that Tan IIA may lead to increased regeneration of glutathione (GSH) from the glutathione disulfide (GSSG) produced during the GSH peroxidase-catalyzed decomposition of H₂O₂ in HUVECs, and the PXR plays a significant role in this process. Tan IIA may also exert protective effects against H₂O₂-induced apoptosis through the mitochondrial apoptosis pathway associated with the participation of PXR. Tan IIA protected HUVECs from inflammatory mediators triggered by H₂O₂ via PXR activation. In conclusion, Tan IIA protected HUVECs against H₂O₂-induced cell injury through PXR-dependent mechanisms.

An Enhanced Grouping Proof for Multiple RFID Readers and Tag Groups

Jian Shen,Haowen Tan,Yang Wang,Sai Ji,Jin Wang 보안공학연구지원센터 2014 International Journal of Control and Automation Vol.7 No.12

RFID authentication on large numbers of tags or tag groups has attracted many researchers’ attention as an extension of initial one-or-two-tags scenarios. Due to demands of RFID application in supply chain, various proofs are proposed in the purpose of solving existing problems of grouping tags identification. However, it is proved that verifiers in these proofs are not aware of abnormal relating devices instantly, which may cause both security and technical risks and lie heavy upon identification of the problematic tags and readers. In this paper, we propose an enhanced grouping proof for multiple RFID readers and tag groups, according to which the verifier is able to cope with multiple readers and tag groups simultaneously and know the detailed status of the problematic tags. In addition, privacy protection is provided by offering mutual authentication between the readers and tags. Moreover, it is hard for the malicious tags to pass the verification in the proposed proof.

Online Cutting Temperature Measurement System Based Thermocouple

Wang zhengyu,Yu xiaoyang,Li guanghui,Tan guangyu 보안공학연구지원센터 2014 International Journal of Control and Automation Vol.7 No.10

In order to measure cutter temperature, the on-line thermocouple temperature measurement system was proposed. In this system, temperature sensing element thermocouple was welded in the flank face close to the cutting edge with double bare wires welding way. With this method, this system has advantages of a single point temperature measurement and no effect on cutter temperature distribution. For a higher sampling rate, two AD were used to sample alternately; and for the convenient signal transmission when the cutter is rotating at high speed, wireless transmission was adopted to transmit thermocouple output signal and cold side temperature signal to the host computer. After temperature compensation to the cold side, the compensated temperature will be real-time displayed, stored and played back. System measurement range is 0 ~ 1300 ° C, and the measurement uncertainty is 0.58%. For 8000rpm rotational speed of XH714D machine, experimental results show that the system can measure cutter temperature online, and has advantages of low cost and great practicability.

Ginseng improves cognitive deficit via the RAGE/NF-κB pathway in advanced glycation end product-induced rats

Tan, Xiaobin,Gu, Junfei,Zhao, Bingjie,Wang, Shuyuan,Yuan, Jiarui,Wang, Chunfei,Chen, Juan,Liu, Jiping,Feng, Liang,Jia, Xiaobin The Korean Society of Ginseng 2015 Journal of Ginseng Research Vol.39 No.2

Background: Ginseng, the root of Panax ginseng (PG), is used widely as a herbal medicine to prevent and treat various diseases. Panax ginseng has pharmacological effects on neurodegenerative diseases such as Alzheimer's disease (AD). The present study evaluated the neuroprotective effects of PG and its possible neuroprotective mechanisms in advanced glycation end product (AGE)-induced AD in a rat model. Methods: Advanced glycation end products were injected bilaterally into the CA3 region of the rats' brains. The Morris water maze test and step-down type passive avoidance test were performed to evaluate their memory and cognitive abilities. The oxidation indexes in the hippocampus were detected. Immunohistochemistry was conducted to visualize the receptors for advanced glycation end products (RAGEs) and nuclear factor-kappa-light-chain-enhancer of activated B cell (NF-${\kappa}B$). Results: Behavioral results showed that PG (1 g/kg, 0.5 g/kg, and 0.25 g/kg) significantly shortened the escape latency, remarkably increased the number of crossing times, significantly decreased the number of errors, and prolonged the latency in rats with AGE-induced AD. Panax ginseng also significantly reduced the malondialdehyde level, increased the glutathione content, and increased superoxide dismutase activity in the hippocampus. Panax ginseng significantly decreased the expression of RAGE and NF-${\kappa}B$. The blockade of anti-RAGE antibody could significantly reduce AGE-induced impairments and regulate these expressions. Conclusion: Our results demonstrated that PG significantly inhibits AGE-induced memory impairment and attenuates Alzheimer-like pathophysiological changes. These neuroprotective effects of PG may be associated with the RAGE/NF-${\kappa}B$ pathway. Our results provided the experimental basis for applying PG in preventing and treating AD.

New Safrole Oxide Derivatives: Synthesis and in vitro Antiproliferative Activities on A549 Human Lung Cancer Cells

Wang, Li-Ying,Wang, Xiu-Hua,Tan, Jia-Lian,Xia, Shuai,Sun, Heng-Zhi,Shi, Jin-Wen,Jiang, Ming-Dong,Fang, Liang,Zuo, Hua,Dupati, Gautam,Jang, Kiwan,Shin, Dong-Soo Korean Chemical Society 2012 Bulletin of the Korean Chemical Society Vol.33 No.11

A number of novel small molecules, safrole oxide derivatives 4a-c, 6a-c, 9a-h, were synthesized by the reaction of safrole oxide with anilines 3 and 5, or its alkyl allyl ether derivative 7 with alkyl bromide 8 in moderate yields. The antiproliferative effects of all the target molecules on A549 cell growth were investigated and it was found that the 14 novel compounds could suppress A549 lung cancer cell growth. Among them, compound 6b was the most effective compound in inhibiting the proliferation of A549 cells.

The Application of Fuzzy Logic to Assess the Performance of Participants and Components of Building Information Modeling

Wang, Bohan,Yang, Jin,Tan, Adrian,Tan, Fabian Hadipriono,Parke, Michael Korea Institute of Construction Engineering and Ma 2018 Journal of construction engineering and project ma Vol.8 No.4

In the last decade, the use of Building Information Modeling (BIM) as a new technology has been applied with traditional Computer-aided design implementations in an increasing number of architecture, engineering, and construction projects and applications. Its employment alongside construction management, can be a valuable tool in helping move these activities and projects forward in a more efficient and time-effective manner. The traditional stakeholders, i.e., Owner, A/E and the Contractor are involved in this BIM system that is used in almost every activity of construction projects, such as design, cost estimate and scheduling. This article extracts major features of the application of BIM from perspective of participating BIM components, along with the different phrases, and applies to them a logistic analysis using a fuzzy performance tree, quantifying these phrases to judge the effectiveness of the BIM techniques employed. That is to say, these fuzzy performance trees with fuzzy logic concepts can properly translate the linguistic rating into numeric expressions, and are thus employed in evaluating the influence of BIM applications as a mathematical process. The rotational fuzzy models are used to represent the membership functions of the performance values and their corresponding weights. Illustrations of the use of this fuzzy BIM performance tree are presented in the study for the uninitiated users. The results of these processes are an evaluation of BIM project performance as highly positive. The quantification of the performance ratings for the individual factors is a significant contributor to this assessment, capable of parsing vernacular language into numerical data for a more accurate and precise use in performance analysis. It is hoped that fuzzy performance trees and fuzzy set analysis can be used as a tool for the quality and risk analysis for other construction techniques in the future. Baldwin's rotational models are used to represent the membership functions of the fuzzy sets. Three scenarios are presented using fuzzy MEAN, AND and OR gates from the lowest to intermediate levels of the tree, and fuzzy SUM gate to relate the intermediate level to the top component of the tree, i.e., BIM application final performance. The use of fuzzy MEAN for lower levels and fuzzy SUM gates to reach the top level suggests the most realistic and accurate results. The methodology (fuzzy performance tree) described in this paper is appropriate to implement in today's construction industry when limited objective data is presented and it is heavily relied on experts' subjective judgment.