Effect of Interface on Mechanical Properties and Stamping Formability of Ti/Al Multilayered Composites

Miao Cao,Hui‑Qin Chen,Kun‐Kun Deng,Xing‑Wang Duan,Shuang Liu,Xin Che,Fei Li 대한금속·재료학회 2023 METALS AND MATERIALS International Vol.29 No.5

Ti/Al multilayered composites (LMCs) with 3-layers, 5-layers and 7-layers were prepared by hot‐pressing and hot‐rolling. Theeffects of the interface on the mechanical properties and stamping formability of LMCs were revealed. The results indicatethat the TiAl3phases at the interface thicken gradually with the increase of layers. As the layers of LMCs increases, boththe grain size and the basal texture strength of Ti decrease, and Ti possesses a higher Schmid factors (SF) and more uniformSF distribution, which promotes the overall coordinated deformation of LMCs. The elongation (EL) of LMCs graduallyincreases at the expense of the strength with the increase of layers. The stress–strain transfer across the interface, the releaseof residual stress through interfacial microcracks, and the improvement of the interfacial metallurgical bonding strengthare all conducive to the coordinated deformation between Ti and Al layers, thus the strength of LMCs decreases and theEL enhances. Both the yield strength ratio (σs/σb) and plastic strain ratio (r) decrease, while the strain-hardening exponent(n) increases with the increase of layers of LMCs, which are beneficial to improve the stamping formability of LMCs. Thenumber of interface increases with the increase of layers, which hinders crack propagation. Moreover, the microcracks areeasily induced by the brittle TiAl3phase at the interface, and the main cracks deflect obviously and release part energy inthe form of secondary microcracks, thus delaying the failure of LMCs and improving their stamping formability.

Rhizospheric fungi of Panax notoginseng: diversity and antagonism to host phytopathogens

Miao, Cui-Ping,Mi, Qi-Li,Qiao, Xin-Guo,Zheng, You-Kun,Chen, You-Wei,Xu, Li-Hua,Guan, Hui-Lin,Zhao, Li-Xing The Korean Society of Ginseng 2016 Journal of Ginseng Research Vol.40 No.2

Background: Rhizospheric fungi play an essential role in the plantesoil ecosystem, affecting plant growth and health. In this study, we evaluated the fungal diversity in the rhizosphere soil of 2-yr-old healthy Panax notoginseng cultivated in Wenshan, China. Methods: Culture-independent Illumina MiSeq and culture-dependent techniques, combining molecular and morphological characteristics, were used to analyze the rhizospheric fungal diversity. A diffusion test was used to challenge the phytopathogens of P. notoginseng. Results: A total of 16,130 paired-end reads of the nuclear ribosomal internal transcribed spacer 2 were generated and clustered into 860 operational taxonomic units at 97% sequence similarity. All the operational taxonomic units were assigned to five phyla and 79 genera. Zygomycota (46.2%) and Ascomycota (37.8%) were the dominant taxa; Mortierella and unclassified Mortierellales accounted for a large proportion (44.9%) at genus level. The relative abundance of Fusarium and Phoma sequenceswas high, accounting for 12.9% and 5.5%, respectively. In total,113 fungal isolates were isolated from rhizosphere soil. They were assigned to five classes, eight orders (except for an Incertae sedis), 26 genera, and 43 species based on morphological characteristics and phylogenetic analysis of the internal transcribed spacer. Fusarium was the most isolated genus with six species (24 isolates, 21.2%). The abundance of Phoma was also relatively high (8.0%). Thirteen isolates displayed antimicrobial activity against at least one test fungus. Conclusion: Our results suggest that diverse fungi including potential pathogenic ones exist in the rhizosphere soil of 2-yr-old P. notoginseng and that antagonistic isolates may be useful for biological control of pathogens.

Endophytic fungi harbored in Panax notoginseng: diversity and potential as biological control agents against host plant pathogens of root-rot disease

You-Kun Zheng,Cui-Ping Miao,Hua-Hong Chen,Fang-Fang Huang,Yu-Mei Xia,You-Wei Chen,Li-Xing Zhao 고려인삼학회 2017 Journal of Ginseng Research Vol.41 No.3

Background: Endophytic fungi play an important role in balancing the ecosystem and boosting host growth. In the present study, we investigated the endophytic fungal diversity of healthy Panax notoginseng and evaluated its potential antimicrobial activity against five major phytopathogens causing rootrot of P. notoginseng. Methods: A culture-dependent technique, combining morphological and molecular methods, was used to analyze endophytic fungal diversity. A double-layer agar technique was used to challenge the phytopathogens of P. notoginseng. Results: A total of 89 fungi were obtained from the roots, stems, leaves, and seeds of P. notoginseng, and 41 isolates representing different morphotypes were selected for taxonomic characterization. The fungal isolates belonged to Ascomycota (96.6%) and Zygomycota (3.4%). All isolates were classified to 23 genera and an unknown taxon belonging to Sordariomycetes. The number of isolates obtained from different tissues ranged from 12 to 42 for leaves and roots, respectively. The selected endophytic fungal isolates were challenged by the root-rot pathogens Alternaria panax, Fusarium oxysporum, Fusarium solani, Phoma herbarum, and Mycocentrospora acerina. Twenty-six of the 41 isolates (63.4%) exhibited activity against at least one of the pathogens tested. Conclusion: Our results suggested that P. notoginseng harbors diversified endophytic fungi that would provide a basis for the identification of new bioactive compounds, and for effective biocontrol of notoginseng root rot.

Identification and characterization of BGL11(t), a novel gene regulating leaf-color mutation in rice (Oryza sativa L.)

Zhi-kun Wang,Yun-xiang Huang,Zheng-diao Miao,Zhi-yan Hu,Xin-zhang Song,Li Liu 한국유전학회 2013 Genes & Genomics Vol.35 No.4

A novel bright-green leaf mutant, bgl11, derived from Nipponbare (Oryza sativa L. ssp. japonica) treated by ethyl methanesulfonate (EMS), exhibited a distinct brightgreen leaf phenotype throughout development. Chlorophyll contents of bgl11 decreased significantly than that of its wild-type parent. Genetic analysis suggested that the brightgreen leaf trait was controlled by a single recessive nuclear gene, which was tentatively designed as BGL11(t). To isolate the BGL11(t) gene, a map-based cloning strategy was employed, and the gene was finally mapped in a 94.7 kb region between marker InDel11-5 and InDel11-9 on the long arm of chromosome 11, in which no gene leaded to leaf-color mutation had been mapped or cloned. Cloning and sequencing analysis revealed that, LOC_Os11g38040, which was predicted to encode an expressed protein, had a 9 bp segment deletion in the coding region of bgl11. Furthermore, the transgenic plants with wild-type gene LOC_Os11g38040were restored to normal phenotype. Accordingly, the gene (LOC_Os11g38040) was identified as the BGL11(t) gene. These results are very valuable for further study on BGL11(t)gene and illuminating the mechanism of chloroplast development in rice.

Endophytic fungi harbored in Panax notoginseng: diversity and potential as biological control agents against host plant pathogens of root-rot disease

Zheng, You-Kun,Miao, Cui-Ping,Chen, Hua-Hong,Huang, Fang-Fang,Xia, Yu-Mei,Chen, You-Wei,Zhao, Li-Xing The Korean Society of Ginseng 2017 Journal of Ginseng Research Vol.41 No.3

Background: Endophytic fungi play an important role in balancing the ecosystem and boosting host growth. In the present study, we investigated the endophytic fungal diversity of healthy Panax notoginseng and evaluated its potential antimicrobial activity against five major phytopathogens causing root-rot of P. notoginseng. Methods: A culture-dependent technique, combining morphological and molecular methods, was used to analyze endophytic fungal diversity. A double-layer agar technique was used to challenge the phytopathogens of P. notoginseng. Results: A total of 89 fungi were obtained from the roots, stems, leaves, and seeds of P. notoginseng, and 41 isolates representing different morphotypes were selected for taxonomic characterization. The fungal isolates belonged to Ascomycota (96.6%) and Zygomycota (3.4%). All isolates were classified to 23 genera and an unknown taxon belonging to Sordariomycetes. The number of isolates obtained from different tissues ranged from 12 to 42 for leaves and roots, respectively. The selected endophytic fungal isolates were challenged by the root-rot pathogens Alternaria panax, Fusarium oxysporum, Fusarium solani, Phoma herbarum, and Mycocentrospora acerina. Twenty-six of the 41 isolates (63.4%) exhibited activity against at least one of the pathogens tested. Conclusion: Our results suggested that P. notoginseng harbors diversified endophytic fungi that would provide a basis for the identification of new bioactive compounds, and for effective biocontrol of notoginseng root rot.

Rhizospheric fungi of Panax notoginseng: diversity and antagonism to host phytopathogens

Cui-Ping Miao,Qi-Li Mi,Xin-Guo Qiao,You-Kun Zheng,You-Wei Chen,Li-Hua Xu,Hui-Lin Guan,Li-Xing Zhao 고려인삼학회 2016 Journal of Ginseng Research Vol.40 No.2

Background: Rhizospheric fungi play an essential role in the plantesoil ecosystem, affecting plant growth and health. In this study, we evaluated the fungal diversity in the rhizosphere soil of 2-yr-old healthy Panax notoginseng cultivated in Wenshan, China. Methods: Culture-independent Illumina MiSeq and culture-dependent techniques, combining molecular and morphological characteristics, were used to analyze the rhizospheric fungal diversity. A diffusion test was used to challenge the phytopathogens of P. notoginseng. Results: A total of 16,130 paired-end reads of the nuclear ribosomal internal transcribed spacer 2 were generated and clustered into 860 operational taxonomic units at 97% sequence similarity. All the operational taxonomic units were assigned to five phyla and 79 genera. Zygomycota (46.2%) and Ascomycota (37.8%) were the dominant taxa; Mortierella and unclassified Mortierellales accounted for a large proportion (44.9%) at genus level. The relative abundance of Fusarium and Phoma sequenceswas high, accounting for 12.9% and 5.5%, respectively. In total,113 fungal isolates were isolated from rhizosphere soil. They were assigned to five classes, eight orders (except for an Incertae sedis), 26 genera, and 43 species based on morphological characteristics and phylogenetic analysis of the internal transcribed spacer. Fusarium was the most isolated genus with six species (24 isolates, 21.2%). The abundance of Phoma was also relatively high (8.0%). Thirteen isolates displayed antimicrobial activity against at least one test fungus. Conclusion: Our results suggest that diverse fungi including potential pathogenic ones exist in the rhizosphere soil of 2-yr-old P. notoginseng and that antagonistic isolates may be useful for biological control of pathogens.

중국 주택가격의 결정요인 분석: - 70개 도시를 중심으로 -

장 묘(Miao Zhang),최배근(Pae Kun Choi) 건국대학교 경제경영연구소 2011 商經硏究 Vol.36 No.2

금년은 중국이 개혁개방에 나선지 32년째 되는 해이다. 그동안 중국의 주택시장은 주택건설 규모 및 거래 규모면에서 빠른 속도로 증가하여 왔으며, 이렇게 주택건설을 중심으로 한 부동산산업은 중국경제 발전의 중요한 원동력이 되었다. 그러나 1998년 이후 중국의 주택가격은 전반적으로 지속적인 상승을 보이는 가운데 일정기간 동안은 폭등양상까지 나타냄으로써 중국경제의 안정적 성장에 부정적 요인이 되고 있다. 본 논문에서는 우선 중국의 주택시장 현황 과 법 및 정책 소개하고 중국부동산 가격에 영향을 미치는 요인들을 이론적으로 분석한다. 이어서 시계열 자료를 활용하여 중국 주택가격의 변동요인에 대한 실증 분석을 시도하였다. 실증분석에서는 자료의 공적분 관계를 고려하여 벡터오차수정모형(VECM)을 활용하였다. 마지막으로 실증분석의 결과에 기초해 부동산 정책에 대한 의견을 제출할 것이다. 실증분석에서는 자료의 공적분 관계를 고려하여 벡터오차수정모형(VECM)을 활용하였다. 공적분 관계를 고려한 인과관계 검증과 충격반응분석을 실시하여 70개 도시 주택 평균가격에 대하여 주택가격지수와 주요 거시경제변수간의 선후관계와 특정 변수의 충격 후 모든 개별 변수의 반응의 크기 및 방향성을 파악하였다. 공적분관계가 6개 존재한다는 귀무가설을 기각하여 다섯 변수사이에 공적분관계가 3개 존재한다는 것을 알 수 있다. 한편, 주택가격은 주민가처분소득과 (+)의 장기적 관계, 대출금리와 (-)의 장기적 관계, 주택투자와 (+)의 장기적 관계, M2와 (-)의 장기적 관계를 갖는다는 것을 알 수 있었다. 한편, 한국과 달리 중국환율은 주택가격에 영향이 거의 없는 것으로 나타났다. Since China s economic reform and opening 32 years ago, strong governmental encouragement and support for the real estate industry, China s real estate industry realized extraordinary development, which has been a driving force in China s overall economic development. However, from 1998 on steady increase in housing prices and sky- rocketing price increases for some periods have turned into a negative factor on the health of the national economy. In this study, we introduce the Chinese housing market condition, law, policy and some problem at first. And then we examine empirically the economic relationship between housing prices and main macroeconomic variables, all of them are the key variables Chinese government uses as policy instruments and macroeconomic performance indicators. We used the unit root test, Johansen s cointegration tests, reveal that all key variables have cointegration relationships. We then estimated Vector Error-Correction Model and impulse response analyses to temporal responses of key variables when a shock occurs in each variable. we consider 70 cities housing average price index and five key macroeconomic variables which all found to be nonstationary based on the unit root test. Johansen s cointegration tests reveal that the housing markets have cointegration relationships, three for the housing average price. We then estimated vector autoregressive models incorporating the identified cointegrating relationships. Finally, we conducted impulse response analyses to track temporal responses of key variables when a shock occurs in each variable.

Synergistic effect of Cu and Ru decoration on g-C3N4 for electrocatalytic CO2 reduction

Chechia Hu,Miao-Ting Liu,Arisu Sakai,Masaaki Yoshida,Kun-Yi Andrew Lin,Chun-Chieh Huang 한국공업화학회 2022 Journal of Industrial and Engineering Chemistry Vol.115 No.-

Electrocatalytic CO2 reduction is an emerging approach for the reduction of CO2 in a feasible, green, andeffective manner. In this study, bimetallic compounds of Cu and Ru were both decorated onto ap-conjugated g-C3N4 surface (CuxRuyCN), which functioned as an electrode for electrochemical CO2reduction. From the X-ray photoelectron and X-ray absorption spectra, Cu and Ru on CuxRuyCN wereidentified as the oxidative states of CuO/Cu2O and RuO2, respectively. The mixed states of CuO andCu2O served as active sites to both adsorb and activate CO2 for effective reduction, while RuO2synergistically served as the hole-enrichment center and transferred H protons to promote CO2 reduction. Consequently, the electrochemical current density of CuxRuyCN was significantly enhanced comparedwith the corresponding densities of CN or Cu-doped CN. The current density of CuxRuyCN reduced to lessthan 0.05 mA cm2 at an applied voltage of 1.5 V in an air or Ar atmosphere, indicating that the highcurrent density of CuxRuyCN was associated with the flow of CO2 and its reduction. Moreover, the currentdensity of CuxRuyCN was maintained at approximately 0.3 mA cm2 for at least 2000 s at an appliedvoltage of 1.4 V (vs Ag/AgCl), indicating its high stability during CO2 reduction. In summary, both Cuand Ru-modified g-C3N4 samples used to produce CuO/Cu2O- and RuO2-decorated g-C3N4 acted as effectivecatalysts for electrocatalytic CO2 reduction and demonstrated several potential electrochemicalapplications.

Microscopic Mechanisms and Acoustic Emission Characteristics of Sandy Mudstone under Different Water Saturations

Xiao-ming Sun,Fu-kun Shi,Ming-qun Zhu,Jia-xu Ding,Lin-sen He,Zhi-hu Li,Tong Zhang,Cheng-yu Miao 대한토목학회 2024 KSCE Journal of Civil Engineering Vol.28 No.1

In order to study the damage mechanism of surrounding rocks under water-rock coupling, an experimental study on the microscopic law of water absorption and mechanics of sandy mudstone was carried out in the sandy mudstone stratum of Wanfu coal mine in Shandong, China. The results indicate that the strength of sandy mudstone exhibits three stages of relative softening, rapid softening, and decelerated softening. The speed of water molecules entering the microscopic pore structure was analyzed based on the percentage of water molecules in the pore structure. The acoustic emission energy release process is divided into energy accumulation stage, stable release stage and intense release stage. With the increase of water content saturation,  (Spectral width of the multifractal spectrum) tends to decrease and the distribution of events is gradually uniform. The action of water gradually expands and penetrates the cracks and pores inside the sandy mudstone, which makes f (Frequency of occurrence of the signal) change from negative to positive values.

Diversity, distribution, and antagonistic activities of rhizobacteria of Panax notoginseng

Fan, Ze-Yan,Miao, Cui-Ping,Qiao, Xin-Guo,Zheng, You-Kun,Chen, Hua-Hong,Chen, You-Wei,Xu, Li-Hua,Zhao, Li-Xing,Guan, Hui-Lin The Korean Society of Ginseng 2016 Journal of Ginseng Research Vol.40 No.2

Background: Rhizobacteria play an important role in plant defense and could be promising sources of biocontrol agents. This study aimed to screen antagonistic bacteria and develop a biocontrol system for root rot complex of Panax notoginseng. Methods: Pure-culture methods were used to isolate bacteria from the rhizosphere soil of notoginseng plants. The identification of isolates was based on the analysis of 16S ribosomal RNA (rRNA) sequences. Results: A total of 279 bacteria were obtained from rhizosphere soils of healthy and root-rot notoginseng plants, and uncultivated soil. Among all the isolates, 88 showed antagonistic activity to at least one of three phytopathogenic fungi, Fusarium oxysporum, Fusarium solani, and Phoma herbarum mainly causing root rot disease of P. notoginseng. Based on the 16S rRNA sequencing, the antagonistic bacteria were characterized into four clusters, Firmicutes, Proteobacteria, Actinobacteria, and Bacteroidetesi. The genus Bacillus was the most frequently isolated, and Bacillus siamensis (Hs02), Bacillus atrophaeus (Hs09) showed strong antagonistic activity to the three pathogens. The distribution pattern differed in soil types, genera Achromobacter, Acidovorax, Brevibacterium, Brevundimonas, Flavimonas, and Streptomyces were only found in rhizosphere of healthy plants, while Delftia, Leclercia, Brevibacillus, Microbacterium, Pantoea, Rhizobium, and Stenotrophomonas only exist in soil of diseased plant, and Acinetobacter only exist in uncultivated soil. Conclusion: The results suggest that diverse bacteria exist in the P. notoginseng rhizosphere soil, with differences in community in the same field, and antagonistic isolates may be good potential biological control agent for the notoginseng root-rot diseases caused by F. oxysporum, Fusarium solani, and Panax herbarum.