Influence of Initial Pearlite Morphology on the Microstructure Evolution During Heat Treatment of 1.0C–1.5Cr Steel

Zhen‑Xing Li,Chang‑Sheng Li,Seong‑Hoon Kim,Dong‑Woo Suh 대한금속·재료학회 2019 METALS AND MATERIALS International Vol.25 No.1

Effect of initial pearlite morphology on the microstructure evolution during spheroidization annealing and subsequent hardeningtreatment was studied in hot-rolled 1.0C–1.5Cr bearing steel. The ferrite-to-austenite transformation in spheroidizationannealing can be accelerated by refining the pearlite interlamellar spacing and pearlite colony size. Decreasing interlamellarspacing is also beneficial to increasing the number density of undissolved cementite, leading to the refining of final spheroidizedcementite. During the re-austenitizing process of hardening treatment, the smaller initial spheroidized cementiteleads to faster cementite dissolution and finer undissolved cementite particles. The prior austenite grain size after hardeningtreatment can also be decreased by refining the initial pearlite microstructure.

Microstructure evolution and enhanced vacuum tribological performance of Ni-doped WS₂ composite coating

Xu, Shu-Sheng,Weng, Li-Jun,Liu, Yu-Zhen,Kang, Kyeong-Hee,Kim, Chang-Lae,Kim, Dae-Eun Elsevier Sequoia 2017 Surface & coatings technology Vol.325 No.-

<P><B>Abstract</B></P> <P>Ni-doped WS<SUB>2</SUB> composite coatings with various Ni contents were co-deposited using a radio frequency sputtering system on silicon wafer and AISI 440C stainless steel substrates. The microstructural characteristics of the WS<SUB>2</SUB>-Ni composite coatings and their tribological properties in vacuum were assessed. During introduction of Ni dopant in the WS<SUB>2</SUB>-Ni composite coating the sulfur/tungsten (S/W) ratio in the coating increased due to reduced preferential resputtering of sulfur atoms in the growing coating. The microstructure of the WS<SUB>2</SUB>-Ni composite coating varied from a fine columnar structure for Ni content equal to or less than 7.7at.% to a featureless structure as the Ni content increased further. The Ni dopant inhibited the growth of the coarse columnar WS<SUB>2</SUB> platelets which was accompanied by nanocrystallization and amorphization of the composite coating structure. WS<SUB>2</SUB>-Ni composite coatings with fine columnar structure exhibited relatively low hardness but showed a high tendency to form a lubricating transfer layer. It also demonstrated low brittleness and prolonged wear life in vacuum condition compared to coatings with dense featureless structure. The variation in tribological performance between the composite coatings resulted from the different wear mechanisms associated with their distinct microstructures.</P> <P><B>Highlights</B></P> <P> <UL> <LI> Microstructure of WS<SUB>2</SUB> coating was modified by incorporating Ni as a dopant. </LI> <LI> The introduction of Ni increased the S/W ratio of the WS<SUB>2</SUB> composite coating. </LI> <LI> High Ni content in the WS<SUB>2</SUB> coating led to high brittleness and low wear resistance. </LI> <LI> WS<SUB>2</SUB>–5at.% Ni coating showed 5 times longer wear life than pure WS<SUB>2</SUB> film in vacuum. </LI> <LI> Superior tribological properties were attributed to transfer layer and high hardness. </LI> </UL> </P> <P><B>Graphical abstract</B></P> <P>[DISPLAY OMISSION]</P>

Ecofriendly high-performance ionic soft actuators based on graphene-mediated cellulose acetate

Nan, Minghui,Wang, Fan,Kim, Seokjae,Li, Hao,Jin, Zhen,Bang, Doyeon,Kim, Chang-Sei,Park, Jong-Oh,Choi, Eunpyo Elsevier 2019 Sensors and actuators. B Chemical Vol.301 No.-

<P><B>Abstract</B></P> <P>Ionic-type artificial muscles with eco-friendly, biodegradable, and biocompatible functionalities have attracted attention for a wide range of potential applications in wearable electronics, soft haptic-feedback systems, and active biomedical devices. Here, we report on the development of an ecofriendly high-performance ionic soft actuator based on biofriendly cellulose acetate (CA), graphene nanopowders (GN), ionic liquid (IL) as a plasticizer, and biofriendly-flexible-nonmetallic conducting polymer poly(3,4-ethylene-dioxythiopene)-polystyrenesulfonate (PEDOT: PSS) as an electrode, thereby realizing a novel ecofriendly CA-IL-GN actuator with a large bending mechanical deformation and a fast response time. The proposed CA-IL-GN (0.2 wt%) nanocomposite membrane exhibited dramatic increments in specific capacitance (2.92 times) and Young’s modulus (2.38 times), thus leading to a 2.9 times larger bending deformation and a 4.8 times faster response than those of pure CA-IL actuator. Therefore, the developed ecofriendly high-performance CA-IL-GN actuator can be considered to be a promising candidate for human-friendly electronics, including artificial muscles, flexible haptic devices, soft wearable devices, and bio-medical devices, due to its cost-effectiveness, large bending mechanical actuation, fast response, and bio-friendly functionalities.</P> <P><B>Highlights</B></P> <P> <UL> <LI> Ecofriendly soft actuator based on cellulose acetate, graphene nanopowders, ionic liquid as plasticizer, and PEDOT:PSS as soft electrode. </LI> <LI> Proposed membrane exhibited increments in specific capacitance and Young’s modulus compare with a pure cellulose acetate actuator. </LI> <LI> Proposed actuator showed a 2.9 times larger bending deformation and a 4.8 times faster response than those of pure cellulose acetate actuator. </LI> </UL> </P>

Pseudonocardia rhizophila sp. nov., a novel actinomycete isolated from a rhizosphere soil

Li, Jie,Zhao, Guo-Zhen,Huang, Hai-Yu,Zhu, Wen-Yong,Lee, Jae-Chan,Kim, Chang-Jin,Xu, Li-Hua,Zhang, Li-Xin,Li, Wen-Jun Springer-Verlag 2010 Antonie van Leeuwenhoek Vol.98 No.1

Expression and Clinical Significance of Myeloid Derived Suppressor Cells in Chronic Hepatitis B Patients

Lu, Li-Rong,Liu, Jing,Xu, Zhen,Zhang, Geng-Lin,Li, De-Chang,Lin, Chao-Shuang Asian Pacific Journal of Cancer Prevention 2014 Asian Pacific journal of cancer prevention Vol.15 No.10

We here document discovery of expression profile of myeloid derived suppressor cells (MDSCs) in chronic hepatitis B (CHB) patients and changes in the course of disease. The study population was composed of 75 outpatient HBV cases and 15 healthy control cases. Peripheral blood samples were collected for separation of mononuclear cells. Levels of MDSCs labeled with Lin-DR-CD11b+CD33+ obtained from peripheral blood mononuclear cells (PBMC), were revealed to have significant differences between the CHB and other groups. They were 0.414% for health control cases and 0.226% for CHB cases (Z=-2.356, p=0.0189). It also observed that the group of HBeAg positive cases had significant difference in MDSCs/PBMC median ($X^2=11.877$, p=0.003), compared with group of HBeAg negative cases and the healthy control group. It suggested considerable MDSCs might be involved in HBeAg immune tolerance. In addition, negative correlations between MDSCs/PBMC and parameters of ALT, AST and TBil, while positive correlation between MDSCs/PBMC and ALB parameter were found. Multiple comparisons between the four phases and health control phase again, there was a statistically sifnificant difference ($X^2=17.198$, p=0.002). Taken together, these findings may provide a new immunotherapy strategy for reduced the expression levels of MDSCs in CHB patients, through induction of an autoimmune response to virus removal.

In Vivo Effects of Ginseng Saponins on Hair Follicle Development in C57BL/6 Mouse Model

Zheng Li,Li Juan Gu,Mi Ra Lee,Bai Shen Sun,Jing Jie Li,Dong Liang Zhang,Lei Liu,Chun Yan Wang,Zhen Wang,Beom Sik Yun,Chang Keun Sung 한국식품저장유통학회 ( 구 한국농산물저장유통학회 ) 2009 한국식품저장유통학회 학술대회 Vol.2009 No.-

Lithium Content of Some Teas and Their Infusions Consumed in China

Lei Wang,Li Jiang,Zhen-Yong Zhao,Chang-Yan Tian 한국식품과학회 2014 Food Science and Biotechnology Vol.23 No.1

Interest into the benefits of lithium (Li) hasraised the issue that there are few data available onamounts of Li contained in different types of teas. Liconcentrations of 30 teas and their infusions consumed inChina were determined by inductively coupled plasmamass spectroscopy (ICP-MS). The highest Li content wasfound in Luobuma (Apocynum venetum) tea (>11 ppm). Licontents of other types of teas ranged from 0.02 to 0.6ppm. According to our data and calculations, a dailyconsumption of 10 g Luobuma tea can give >85 μg Liintake. This is more than 85% of the minimum humanadult Li requirement. However, other types of teas (10 g/day) can only provide <3% of the minimum Li requirement.

Evaluation of the Oral Acute Toxicity of Black Ginseng in Rats

Mi-Ra Lee,Chang-Jin Oh,Zheng Li,Jing-Jie Li,Chun-Yan Wang,Zhen Wang,Li-Juan Gu,Sang-Hwa Lee,Jae-Il Lee,Beong-Ou Lim,Chang-Keun Sung 고려인삼학회 2011 Journal of Ginseng Research Vol.35 No.1

We studied the acute oral toxicity of black ginseng (BG) produced by heat process in rats. Single acute BG extract doses of 0, 5, 10, and 15 g/㎏ dissolved in saline were administered by oral gavage and the animals were kept under observation for 14 days. The single administration of BG extract up to 15 g/㎏ did not produce mortality, behavioral change or abnormal clinical signs in the rats. These results indicated that the oral LD?? of the BG extract in the rats is higher than 15 g/㎏. Compared to the control group, no treatment-related biologically signifi cant effects of BG extract were noted in the measurements of the body weight or food intake. At the end of the period, the biochemical parameters and hematological parameters were analyzed in the plasma and blood. A histopathological examination of the liver and kidney was also conducted. Only the blood nitrogen urea and potassium levels in the biochemical indices showed signifi cant differences at 10 and 15 g/㎏ doses of BG extract compared to the control group. These changes were not considered to be due to the toxicity. None of the other clinical chemistry parameters were affected. Therefore, these results indicate that the BG by heat processing is virtually nontoxic.

Evaluation of the Oral Acute Toxicity of Black Ginseng in Rats

Lee, Mi-Ra,Oh, Chang-Jin,Li, Zheng,Li, Jing-Jie,Wang, Chun-Yan,Wang, Zhen,Gu, Li-Juan,Lee, Sang-Hwa,Lee, Jae-Il,Lim, Beong-Ou,Sung, Chang-Keun The Korean Society of Ginseng 2011 Journal of Ginseng Research Vol.35 No.1

We studied the acute oral toxicity of black ginseng (BG) produced by heat process in rats. Single acute BG extract doses of 0, 5, 10, and 15 g/kg dissolved in saline were administered by oral gavage and the animals were kept under observation for 14 days. The single administration of BG extract up to 15 g/kg did not produce mortality, behavioral change or abnormal clinical signs in the rats. These results indicated that the oral $LD_{50}$ of the BG extract in the rats is higher than 15 g/kg. Compared to the control group, no treatment-related biologically significant effects of BG extract were noted in the measurements of the body weight or food intake. At the end of the period, the biochemical parameters and hematological parameters were analyzed in the plasma and blood. A histopathological examination of the liver and kidney was also conducted. Only the blood nitrogen urea and potassium levels in the biochemical indices showed significant differences at 10 and 15 g/kg doses of BG extract compared to the control group. These changes were not considered to be due to the toxicity. None of the other clinical chemistry parameters were affected. Therefore, these results indicate that the BG by heat processing is virtually nontoxic.

Fotemustine, Teniposide and Dexamethasone in Treating Patients with CNS Lymphoma

Wu, Jing-Jing,Wang, Xin-Hua,Li, Ling,Li, Xin,Zhang, Lei,Sun, Zhen-Chang,Fu, Xiao-Rui,Ma, Wang,Chang, Yu,Zhang, Xu-Dong,Han, Li-Juan,Zhang, Ming-Zhi Asian Pacific Journal of Cancer Prevention 2014 Asian Pacific journal of cancer prevention Vol.15 No.11

Purpose: We developed and evaluated a regimen including fotemustine, teniposide and dexamethasone (FTD) for treating patients with central nervous system (CNS) lymphoma based on pharmacokinetic properties of individual agents and in combination. Patients and Methods: In a comparison study, 8 patients with primary CNS lymphoma (PCNSL) and 8 with secondary CNS lymphoma (SCNSL) were treated with FTD (comprising fotemustine 100 mg/m2, 1h infusion, day 1; teniposide 60 mg/m2, >0.5 h infusion, on day 2, 3, 4; dexamethasone 40 mg, 1h infusion, on day 1, 2, 3, 4 and 5; and methotrexate 12 mg, cytosine arabinoside 50 mg plus dexamethasone 5 mg intrathecally, on day 2 and 7). Cycles were repeated every 3 weeks. After response assessment, patients received whole brain radiotherapy. Results: Of the 8 PCNSL patients, 4 (50%) achieved CR and 3 (38%) PR, an overall response rate of 88%. Four patients (50%) were in continuing remission at the end of this study after a median follow-up of 30 months (range 10 to 56 months). Of the 8 SCNSL patients the overall response rate was 63% (CR+PR: 38%+25%). All responses were achievable with predictable toxicity mainly reflecting reversible myelosuppression. Conclusion: This study suggests that FTD could be an effective treatment for CNS lymphoma, and is worthy of further evaluation.