Effects of Si on the Microstructure and Work Hardening Behavior of Fe‒17Mn‒1.1C‒xSi High Manganese Steels

Renlong Xiong,Yi Liu,Haitao Si,Huabei Peng,Shanling Wang,Binhan Sun,Hanxin Chen,Hyoung Seop Kim,Yuhua Wen 대한금속·재료학회 2021 METALS AND MATERIALS International Vol.27 No.10

In order to improve the work hardening capacity under low stresses and the yield strength of conventional Hadfield steels, theeffects of Si on the microstructure and work hardening behavior of the Fe‒17Mn‒1.1C‒xSi steels under both quasi-statictensile and low load impact are investigated. It is shown that the increase of the Si contents remarkably improves the yieldstrength by 36 MPa per 1 wt% Si in the investigated steel system without significant sacrifice of ductility. The decreasingeffect of Si on the stacking fault energy is strongly affected by carbon, although the variation of carbon content was small. This led to the unexpected similar stacking fault energy between 1Si and 2Si steel. With the increase of the Si contents forthe steels, the critical strain for the onset of mechanical twinning was lowered, which was controlled by the cooperationbetween the stacking fault energy and solid solution strengthening of Si. This resulted in the earlier initiation of mechanicaltwins and an increase in the twin volume fraction. Therefore, the work hardening capacities under both quasi-static tensileand low load impact tests were enhanced. It was also found that the impact deformation decreased as more mechanical twinsabsorbed the impact energy.

Curved-quartic-function elements with end-springs in series for direct analysis of steel frames

Si-Wei Liu,Jake Lok Yan Chan,Rui Bai,Siu-Lai Chan 국제구조공학회 2018 Steel and Composite Structures, An International J Vol.29 No.5

A robust element is essential for successful design of steel frames with Direct analysis (DA) method. To this end, an innovative and efficient curved-quartic-function (CQF) beam-column element using the fourth-order polynomial shape function with end-springs in series is proposed for practical applications of DA. The member initial imperfection is explicitly integrated into the element formulation, and, therefore, the <i>P</i>-<i>δ</i> effect can be directly captured in the analysis. The series of zero-length springs are placed at the element ends to model the effects of semi-rigid joints and material yielding. One-element-per-member model is adopted for design bringing considerable savings in computer expense. The incremental secant stiffness method allowing for large deflections is used to describe the kinematic motion. Finally, several problems are studied in this paper for examining and validating the accuracy of the present formulations. The proposed element is believed to make DA simpler to use than existing elements, which is essential for its successful and widespread adoption by engineers.

INTERACTIONS OF THE INFRARED BUBBLE N4 WITH ITS SURROUNDINGS

Liu, Hong-Li,Li, Jin-Zeng,Wu, Yuefang,Yuan, Jing-Hua,Liu, Tie,Dubner, G.,Paron, S.,Ortega, M. E.,Molinari, Sergio,Huang, Maohai,Zavagno, Annie,Samal, Manash R.,Huang, Ya-Fang,Zhang, Si-Ju American Astronomical Society 2016 The Astrophysical journal Vol.818 No.1

<P>The physical mechanisms that induce the transformation of a certain mass of gas in new stars are far from being well understood. Infrared bubbles associated with H II regions have been considered to be good samples for investigating triggered star formation. In this paper we report on the investigation of the dust properties of the infrared bubble N4 around the H II. region G11.898+0.747, analyzing its interaction with its surroundings and star formation histories therein, with the aim of determining the possibility of star formation triggered by the expansion of the bubble. Using Herschel PACS and SPIRE images with a wide wavelength coverage, we reveal the dust properties over the entire bubble. Meanwhile, we are able to identify six dust clumps surrounding the bubble, with a mean size of 0.50 pc, temperature of about 22 K, mean column density of 1.7 x 10(22) cm(-2), mean volume density of about 4.4 x 10(4) cm(-3), and a mean mass of 320M(circle dot). In addition, from PAH emission seen at 8 mu m, free-free emission detected at 20 cm, and a probability density function in special regions, we could identify clear signatures of the influence of the H II region on the surroundings. There are hints of star formation, though further investigation is required to demonstrate that N4 is the triggering source.</P>

The Effects of Absorptive Capability and Innovative Culture on Innovation Performance: Evidence from Chinese High-Tech Firms

LIU, Si-Meng,HU, Rui,KANG, Tae-Won Korea Distribution Science Association 2021 The Journal of Asian Finance, Economics and Busine Vol.8 No.3

The innovation of enterprises allowed firms to promote technological innovation as an important choice to improve sustainable competitiveness. This study aims to investigate the relationship between absorptive capacity and innovation performance of Chinese high-tech enterprises and focuses on the mediating role of innovation culture in high-tech enterprises. Data came from surveying high-tech enterprises in China, and the reliability analysis, factor analysis, and correlation analysis, path analysis (SEM) were analyzed using SPSS23, AMOS. The results show that intellectual capital composed of human capital, structural capital, and relational has a significant impact on acquisition performance; intellectual capital is composed of human capital; structural capital has a significant influence on innovation performance; and absorptive capital has a significant impact on innovation performance. In addition, innovative culture plays a partial mediating role between absorptive capacity and innovation performance. The findings of this study suggest that, to ensure the better absorption and operation of knowledge, high-tech enterprises can accumulate more knowledge, promote the transformation of knowledge into technology, and strengthen the capability of knowledge absorptive capacity, and at the same time, create an innovation culture atmosphere and encourage employees to develop new products to achieve enterprise goals in order to promote the improvement of innovation performance.

ST6Gal-I Predicts Postoperative Clinical Outcome for Patients with Localized Clear-cell Renal Cell Carcinoma

Liu, Hai-Ou,Wu, Qian,Liu, Wei-Si,Liu, Yi-Dong,Fu, Qiang,Zhang, Wei-Juan,Xu, Le,Xu, Jie-Jie Asian Pacific Journal of Cancer Prevention 2014 Asian Pacific journal of cancer prevention Vol.15 No.23

Hyperactivated ${\alpha}2$-6-sialylation on N-glycans due to overexpression of the Golgi enzyme ${\beta}$-galactoside: ${\alpha}2$-6-sialyltransferase (ST6Gal-I) often correlates with cancer progression, metastasis, and poor prognosis. This study was aimed to determine the association between ST6Gal-I expression and the risk of recurrence and survival of patients with localized clear-cell renal cell carcinoma (ccRCC) following surgery. We retrospectively enrolled 391 patients (265 in training cohort and 126 in validation cohort) with localized ccRCC underwent nephrectomy at a single center. Tissue microarrays were constructed for immunostaining of ST6Gal-I. Prognostic value and clinical outcomes were evaluated. High ST6Gal-I expression was associated with Fuhrman grade (p<0.001 and p=0.016, respectively) and the University of California Los-Angeles Integrated Staging System (UISS) score (p=0.004 and p=0.017, respectively) in both cohorts. Patients with high ST6Gal-I expression had significantly worse overall survival (OS) (p<0.001 and p<0.001, respectively) and recurrence free survival (RFS) (p<0.001 and p=0.002, respectively) than those with low expression in both cohorts. On multivariate analysis, ST6Gal-I expression remained associated with OS and RFS even after adjusting for the UISS score. Stratified analysis suggested that the association is more pronounced among patients with low and intermediate-risk disease defined by the UISS score. High ST6Gal-I expression is a potential independent adverse predictor of survival and recurrence in ccRCC patients, and the prognostic value is most prominent in those with low and intermediate-risk disease defined by the UISS score.

Investigation on tolerance of Metarhizium flavoviride Ma130821 to environmental stress factors and responses on biological control of larvae of Potosia brevitarsis Lewis

Liu Si‐Yu,Lai You‐Peng,Du Guang‐Zu,Chen Bin 한국곤충학회 2022 Entomological Research Vol.52 No.11

Entomopathogenic fungi of Metarhizium spp., are one of the candidates for eco-friendly pest control instead of chemical control agents. But the development involved in producing a wide range of mycoinsecticides and application of biotechnology widely is restricted, usually due to the defect of slow action and sensitivity to environmental stresses. This study evaluates the tolerance of conidia of Metarhizium flavoviride Ma130821 to high temperature exposure, humidity level, ultraviolet radiation and the pathogenicity against larvae of Potosia brevitarsis Lewis under environmental stresses. Results showed that M. flavoviride Ma130821 had the higher tolerance ability to 40°C with continuous exposure for 24 h, the conidial germination rate was 54.00%, radial growth was 1.59 mm/day and sporulation was 9.37 × 106 conidia/cm2, the ability to desiccation with humidity of 53% (85.33%, 1.94 mm/d, 2.13 × 107 conidia/cm2), the ability of uvioresistant effect with 900 s radiation (98.11%, 0.91 mm/d, 8.87 × 106 conidia/cm2).Thedataofbioassayat artificial adverse condition had been fitted to the time–concentration–mortality (TCM) model. The cumulative mortality of P. brevitarsis larvae was 76.67% with conidial concentrations of 3.41 × 108 conidia/mL. The low lethal concentration (LC50) in 7 days after inoculation (DAI) and short lethal time (LT50) was 6.70 × 109 conidia/mL and 8.02 days, respectively. The mortality also reached to 73.33% at natural condition, with conidial concentration of 3.75 × 108 conidia/mL, but the LT50 delayed to 14.08 days. Our results demonstrate that entomopathogenic fungi M. flavoviride Ma130821, with significantly and superior antistress capacity and high virulence, could be considered a promising biocontrol agent against white grubs.

The comparison of microbial communities in thyroid tissues from thyroid carcinoma patients

Liu Chen-Jian,Chen Si-Qian,Zhang Si-Yao,Wang Jia-Lun,Tang Xiao-Dan,Yang Kun-Xian,Li Xiao-Ran 한국미생물학회 2021 The journal of microbiology Vol.59 No.11

Thyroid carcinoma is a common endocrine organ cancer associated with abnormal hormone secretion, leading to the disorder of metabolism. The intestinal microbiota is vital to maintain digestive and immunologic homeostasis. The relevant information of the microbial community in the gut and thyroid, including composition, structure, and relationship, is unclear in thyroid carcinoma patients. A total of 93 samples from 25 patients were included in this study. The results showed that microbial communities existed in thyroid tissue; gut and thyroid had high abundance of facultative anaerobes from the Proteobacteria phyla. The microbial metabolism from the thyroid and gut may be affected by the thyroid carcinoma cells. The cooccurrence network showed that the margins of different thyroid tissues were unique areas with more competition; the stabilization of microcommunities from tissue and stool may be maintained by several clusters of species that may execute different vital metabolism processes dominantly that are attributed to the microenvironment of cancer.

중국어 상성이 중국인의 한자어 발음에 미치는 영향 연구 : 부분이형동의어를 중심으로

Liu Si Yang,김영주 한국음성학회 2012 말소리와 음성과학 Vol.4 No.2

The purpose of this study is to find the influence of Chinese falling-rising tone on the pitch pattern of corresponding partly-different-form-same-meaning Sino-Korean words delivered by Chinese learners of Korean and to examine how the falling-rising tone of corresponding Chinese words affects the pitch patterns of Sino-Korean words. The scope of this research is limited to Chinese learners of Korean, especially on two groups of Sino-Korean words - AB:CB type and AB:AC type that the are second-most frequently occuring different-form-same-meaning Sino-Korean words. In this study, Chinese learners pronounced both Chinese words and corresponding Sino-Korean words. Learners’ pitch patterns were recorded and analyzed using software and compared with the tone of corresponding Chinese words. Experimental results showed that AB:CB type Sino-Korean words were not affected by Chinese 'falling-rising tone - high and level tone'. As well as AB:CB type, experimental results showed there were no significant influence on the pitch pattern of AB:AC type Sino-Korean words by Chinese falling-rising tone. But it was clear that Chinese learners' made pitch errors on both AB:CB type and AB:AC type Sino-Korean words. In conclusion, the Chinese learners' pitch patterns of partly-different-form-same-meaning Sino-Korean words are different from Korean native speakers', but their pitch errors cannot be attributed to Chinese falling-rising tone.

Transforming Growth Factor Beta-1 C-509T Polymorphism and Cancer Risk: A Meta-analysis of 55 Case-control Studies

Liu, Yang,Lin, Xian-Fan,Lin, Chun-Jing,Jin, Si-Si,Wu, Jin-Ming Asian Pacific Journal of Cancer Prevention 2012 Asian Pacific journal of cancer prevention Vol.13 No.9

Aim: To investigate the association of transforming growth factor-beta 1 (TGF-${\beta}1$) C-509T polymorphism and susceptibility to cancer by means of meta-analysis. Methods: An extensive search was performed to identify eligible case-control studies investigating such a link. The strength of the association between TGF-${\beta}1$ C-509T polymorphism and cancer risk was assessed by pooled odds ratios (ORs) and 95%confidence intervals (95%CIs) in fixed or random effects models. Results: 55 published case-control studies with a total number of 21,639 cases and 28,460 controls were included. Overall, there was no association between TGF-${\beta}1$ C-509T and cancer risk in all genetic comparison models (TT vs. CC: OR=1.01, 95%CI=0.89-1.15; T vs. C: OR=1.01, 95%CI=0.94-1.07). However, a stratified analysis by cancer type indicated -509 T allele was significantly associated with decreased risk of colorectal cancer (CRC) (TT vs. CT/CC: OR=0.85, 95%CI=0.76-0.95), especially for Caucasians (TT vs. CT/CC: OR=0.83, 95%CI=0.71-0.98) and for population-based studies (TT vs. CT/CC: OR=0.78, 95%CI=0.68-0.89). Conclusion: This meta-analysis suggested that TGF-${\beta}1$ C-509T polymorphism might contribute to a decreased risk on colorectal cancer susceptibility, especially for Caucasians.

문화예술 공연장르 재관람 의도의 결정요인 분석: 가구소득의 조절효과를 중심으로

Liu, Si-Yu,윤호정,구희순 한국상품학회 2024 商品學硏究 Vol.42 No.2

Following the increase in performing arts audience numbers post-COVID-19 pandemic, this study comprehensively investigated the determinants influencing cultural and artistic genre selection. Utilizing data from the National Culture and Arts Activity Survey, Korea Performing Arts Box Office Information System (KOPIS) statistics, and online word-of-mouth (eWOM) data obtained through Naver crawling, the research analyzed the impact of viewing experience, satisfaction, price, and online buzz on the intention to re-attend. Employing a multinomial logit model to model the reselection process of cultural and artistic genres, the study reconfirmed that performance price, direct and indirect viewing experiences, satisfaction, and online buzz significantly influence the intention to re-attend. It was found that higher average prices of cultural and artistic genres decrease the intention to select them, while online mentions positively affect this intention. Additionally, the difference in viewing share according to household income level was found to have a moderating effect on the intention to re-attend, with low-income groups preferring popular music and traditional art performances, whereas high-income groups tend to favor Western music. This research provides an in-depth understanding of post-pandemic viewing behaviors and significantly contributes to the analysis of the importance of online word-of-mouth and the impact of economic factors (household income) on cultural consumption patterns.