Two New Species of Placolecis (Lichenized Ascomycota) from China

( An Cheng Yin ),( Xin Yu Wang ),( Dong Liu ),( Yan Yun Zhang ),( Mei Xia Yang ),( Li Juan Li ),( Li Song Wang ) 한국균학회 2019 Mycobiology Vol.47 No.4

Two new species of the lichen genus Placolecis are discovered in China, namely P. kunmingensis An. C. Yin & Li S. Wang and P. sublaevis An. C. Yin & Li S. Wang. The new combination P. loekoesiana (S.Y. Kondr., Farkas, J.J. Woo & Hur) An. C. Yin is proposed. Placolecis kunmingensis is characterized by having simple, spherical or ellipsoid, hyaline spores, and pear-shaped pycnidia; while P. sublaevis can be distinguished by its thallus forming larger aggregations with slightly flattened lobes at the thallus margin, and urn-shaped pycnidia. Descriptions, a phylogenetic tree and a key are provided for all the known Placolecis species in China.

Facile and controllable synthesis of nitrogen self-doped chitosan-derived carbon for high-performance Li-ion batteries

Xia Wentao,Cheng Miao,Hu Jing,Liu Qianqian,Wei Tao,Wang Ruirui,Li Wanfei,Liu Bo 한국탄소학회 2024 Carbon Letters Vol.34 No.1

N-doping content and configurations have a significant effect on the electrochemical performance of carbon anodes. Herein, we proposed a simple method to synthesize highly N self-doped chitosan-derived carbon with controllable N-doping types by introducing 2ZnCO3·3Zn(OH)2 into the precursor. The as-synthesized NC-CS/2ZnCO3·3Zn(OH)2 electrode exhibited more than twice the reversible capacity (518 mAh g−1 after 100 cycles at 200 mA g−1) compared to the NC-CS electrode, superior rate performance and outstanding cycling stability. The remarkable improvement should be mainly attributed to the increase of N-doping content (particularly the pyrrolic-N content), which provided more active sites and favored Li+ diffusion kinetics. This study develops a cost-effective and facile synthesis route to fabricate high-performance N self-doped carbon with tunable doping sites for rechargeable battery applications.

Cathode Materials LaNi1−xCuxO3 for Low Temperature Solid Oxide Fuel Cells

Juncai Sun,Chengli Wang,Song Li,Shijun Ji 한국세라믹학회 2008 한국세라믹학회지 Vol.45 No.12

New cathode materials LaNi1−xCuxO3 (typically LaNi0.8Cu0.2O3) were synthesized using a co-precipitation method. The structure and morphology of the powders were characterized by X-ray diffraction (XRD) and scanning electron microscopy (SEM). The composite material [Ce0.8Sm0.2O2-ä(SDC) and carbonate (Na2CO3,Li2CO3)], NiO and LaNi1−xCuxO3 were used as the electrolyte, anode and cathode, respectively. The electrochemical performance of La-Ni-Cu-O perovskite oxide at low temperatures (400~550oC) was studied. The results showed that LaNi0.8Cu0.2O3 precursor powder prepared through a co-precipitation method and calcined at 860oC for 2 h formed uniform grains with diameters in the range of 400~500 nm. The maximum power density and the short circuit current density of the single cell unit at 550oC were found to be 390 mW/cm2 and 968 mA/cm2, respectively. New cathode materials LaNi1−xCuxO3 (typically LaNi0.8Cu0.2O3) were synthesized using a co-precipitation method. The structure and morphology of the powders were characterized by X-ray diffraction (XRD) and scanning electron microscopy (SEM). The composite material [Ce0.8Sm0.2O2-ä(SDC) and carbonate (Na2CO3,Li2CO3)], NiO and LaNi1−xCuxO3 were used as the electrolyte, anode and cathode, respectively. The electrochemical performance of La-Ni-Cu-O perovskite oxide at low temperatures (400~550oC) was studied. The results showed that LaNi0.8Cu0.2O3 precursor powder prepared through a co-precipitation method and calcined at 860oC for 2 h formed uniform grains with diameters in the range of 400~500 nm. The maximum power density and the short circuit current density of the single cell unit at 550oC were found to be 390 mW/cm2 and 968 mA/cm2, respectively.

Multi-axial strength criterion of lightweight aggregate (LWA) concrete under the Unified Twin-shear strength theory

Wang, Li-Cheng Techno-Press 2012 Structural Engineering and Mechanics, An Int'l Jou Vol.41 No.4

The strength theory of concrete is significant to structure design and nonlinear finite element analysis of concrete structures because concrete utilized in engineering is usually subject to the action of multi-axial stress. Experimental results have revealed that lightweight aggregate (LWA) concrete exhibits plastic flow plateau under high compressive stress and most of the lightweight aggregates are crushed at this stage. For the purpose of safety, therefore, in the practical application the strength of LWA concrete at the plastic flow plateau stage should be regarded as the ultimate strength under multi-axial compressive stress state. With consideration of the strength criterion, the ultimate strength surface of LWA concrete under multi-axial stress intersects with the hydrostatic stress axis at two different points, which is completely different from that of the normal weight concrete as that the ultimate strength surface is open-ended. As a result, the strength criteria aimed at normal weight concrete do not fit LWA concrete. In the present paper, a multi-axial strength criterion for LWA concrete is proposed based on the Unified Twin-Shear Strength (UTSS) theory developed by Prof Yu (Yu et al. 1992), which takes into account the above strength characteristics of LWA under high compressive stress level. In this strength criterion model, the tensile and compressive meridians as well as the ultimate strength envelopes in deviatoric plane under different hydrostatic stress are established just in terms of a few characteristic stress states, i.e., the uniaxial tensile strength $f_t$, the uniaxial compressive strength $f_c$, and the equibiaxial compressive $f_{bc}$. The developed model was confirmed to agree well with experimental data under different stress ratios of LWA concrete.

No Association Between the USP7 Gene Polymorphisms and Colorectal Cancer in the Chinese Han Population

Li, Xin,Wang, Yang,Li, Xing-Wang,Liu, Bao-Cheng,Zhao, Qing-Zhu,Li, Wei-Dong,Chen, Shi-Qing,Huang, Xiao-Ye,Yang, Feng-Ping,Wang, Quan,Wang, Jin-Fen,Xiao, Yan-Zeng,Xu, Yi-Feng,Feng, Guo-Yin,Peng, Zhi-Ha Asian Pacific Journal of Cancer Prevention 2012 Asian Pacific journal of cancer prevention Vol.13 No.5

Colorectal cancer (CRC), now the third most common cancer across the world, is known to aggregate in families. USP7 is a very important protein with an important role in regulating the p53 pathway, which is critical for genomic stability and tumor suppression. We here genotyped eight SNPs within the USP7 gene and conducted a case-control study in 312 CRC patients and 270 healthy subjects in the Chinese Han population. No significant associations were found for any single SNP and CRC risk. Our data eliminate USP7 as a potential candidate gene towards for CRC in the Han Chinese population.

Multi-axial strength criterion of lightweight aggregate (LWA) concrete under the Unified Twin-shear strength theory

Li-cheng Wang 국제구조공학회 2012 Structural Engineering and Mechanics, An Int'l Jou Vol.41 No.4

The strength theory of concrete is significant to structure design and nonlinear finite element analysis of concrete structures because concrete utilized in engineering is usually subject to the action of multi-axial stress. Experimental results have revealed that lightweight aggregate (LWA) concrete exhibits plastic flow plateau under high compressive stress and most of the lightweight aggregates are crushed at this stage. For the purpose of safety, therefore, in the practical application the strength of LWA concrete at the plastic flow plateau stage should be regarded as the ultimate strength under multi-axial compressive stress state. With consideration of the strength criterion, the ultimate strength surface of LWA concrete under multi-axial stress intersects with the hydrostatic stress axis at two different points, which is completely different from that of the normal weight concrete as that the ultimate strength surface is openended. As a result, the strength criteria aimed at normal weight concrete do not fit LWA concrete. In the present paper, a multi-axial strength criterion for LWA concrete is proposed based on the Unified Twin-Shear Strength (UTSS) theory developed by Prof Yu (Yu et al. 1992), which takes into account the above strength characteristics of LWA under high compressive stress level. In this strength criterion model, the tensile and compressive meridians as well as the ultimate strength envelopes in deviatoric plane under different hydrostatic stress are established just in terms of a few characteristic stress states, i.e., the uniaxial tensile strength ft, the uniaxial compressive strength fc, and the equibiaxial compressive fbc. The developed model was confirmed to agree well with experimental data under different stress ratios of LWA concrete.

Influence of FeSe doping on superconducting properties of MgB2 by hybrid microwave method

Cheng Cheng,Zhenjie Feng,Qing Li,Xu Wang,Chuan Yu,Hao Chu,Ya Yang,Changqin Liu,Yiming Cao,Zhe Li,Jingzhe Chen,Chao Jing,Shixun Cao,Jincang Zhang 한국물리학회 2017 Current Applied Physics Vol.17 No.11

The effect of FeSe doping on the physical properties of MgB2 is studied. Bulk samples of the FeSe doped MgB2 with weight ratio x ðFeSe : MgB2Þ ¼ 0%; 3%; 7% and 10% were prepared by hybrid microwave method. It is proved that FeSe is not stable together with MgB2. Fe2þ enters into MgB2 lattice, some Mg2þ and Se2『 are combined into the new impurity compound MgSe. The superconducting transition temperature (Tc) slightly decreased with increasing doping content of FeSe from R-T and M-T curves, which results from the substitution of Mg2þ by Fe2þ in the MgB2 lattice. The Jc increase slightly with the FeSe doping content increasing from 3 wt % to 10 wt %, which results from the increasing MgSe impurity pinning centers.

Field Emission from TiO2/Ti Nanotube Array Films Modified with Carbon Nanotubes

Cheng-Wei Wang,Rui-Sheng Guo,Jian-Biao Chen,Yan Li,Jian Wang,Wei-Min Liu 한국물리학회 2009 THE JOURNAL OF THE KOREAN PHYSICAL SOCIETY Vol.55 No.6

Well-aligned TiO2/Ti nanotube array films were synthesized by using anodic oxidation of titanium in 0.5-wt% HF and were modified with carbon nanotubes (CNTs) assembled by using catalyzed chemical vapor deposition (CVD) at 650 ˚C. The morphology and the quality of the films were assessed with field emission scanning electron microscopy and Raman spectrometry (325 nm). The field emission characteristics of such TiO2/Ti nanostructures were investigated before and after being modified with CNTs. The results show that the TiO2/Ti nanotube arrays possess a moderate turn-on electric field of 7.4 V/µm, a field emission current density of 2.7 mA/cm2 at 23 V/µm. It is noteworthy that the turn-on field of the TiO2/Ti nanotube arrays modified with CNTs is decreased significantly to 1.3 V/µm, and the emission current density is increased to 10 mA/cm2 at 5.6 V/µm. This novel structure shows high emission efficiency as a field emitter. Well-aligned TiO2/Ti nanotube array films were synthesized by using anodic oxidation of titanium in 0.5-wt% HF and were modified with carbon nanotubes (CNTs) assembled by using catalyzed chemical vapor deposition (CVD) at 650 ˚C. The morphology and the quality of the films were assessed with field emission scanning electron microscopy and Raman spectrometry (325 nm). The field emission characteristics of such TiO2/Ti nanostructures were investigated before and after being modified with CNTs. The results show that the TiO2/Ti nanotube arrays possess a moderate turn-on electric field of 7.4 V/µm, a field emission current density of 2.7 mA/cm2 at 23 V/µm. It is noteworthy that the turn-on field of the TiO2/Ti nanotube arrays modified with CNTs is decreased significantly to 1.3 V/µm, and the emission current density is increased to 10 mA/cm2 at 5.6 V/µm. This novel structure shows high emission efficiency as a field emitter.

Dietary exposure and human risk assessment of phthalate esters based on total diet study in Cambodia

Cheng, Zhang,Li, Han-Han,Wang, Hong-sheng,Zhu, Xue-Mei,Sthiannopkao, Suthipong,Kim, Kyoung-Woong,Yasin, Mohamed Salleh Mohamed,Hashim, Jamal Hisham,Wong, Ming-Hung Elsevier 2016 Environmental research Vol.150 No.-

<P><B>Abstract</B></P> <P>Phthalate esters are used in a wide variety of consumer products, and human exposure to this class of compounds is widespread. Nevertheless, studies on dietary exposure of human to phthalates are limited. In this study, to assess the daily intakes of phthalate esters and the possible adverse health impacts, different food samples were collected from three areas of Cambodia, one of the poorest countries in the world. The ∑phthalate ester concentrations in Kampong Cham, Kratie and Kandal provinces ranged from 0.05 to 2.34 (median 0.88) μgg<SUP>−1</SUP>, 0.19–1.65 (median 0.86) μgg<SUP>−1</SUP> and 0.24–3.05 (median 0.59) μgg<SUP>−1</SUP> wet weight (ww), respectively. Di-2-Ethylhexyl phthalate (DEHP) and diisobutyl phthalate (DiBP) were the predominant compounds among all foodstuffs. The estimated daily intake (EDI) of phthalate esters for the general population in Kampong Cham, Kratie and Kandal was 34.3, 35.6 and 35.8μgkg<SUP>−1</SUP> bw d<SUP>−1</SUP>, respectively. The dietary daily intake of DEHP, benzylbutyl phthalate (BBP) and di-n-butyl phthalate (DBP) in Kampong Cham, Kratie and Kandal were below the tolerable daily intakes (TDI) imposed by the European Food Safety Authority (EFSA) and reference doses (RfD) imposed by The United States Environmental Protection Agency (USEPA). Rice contributed the greatest quantity of DEHP to the daily intake in Cambodia so may deserve further exploration. To our knowledge, this is the first study to investigate the occurrence and the daily intakes of phthalate esters in Cambodia.</P> <P><B>Highlights</B></P> <P> <UL> <LI> Phthalate esters concentration in daily foodstuffs collected from Cambodia. </LI> <LI> Investigate the bioaccessbility of phthalate esters via the foodstuffs consumption. </LI> <LI> Health risk evaluation of dietary exposure to phthalate esters. </LI> </UL> </P>

Influence of fracture characters on flow distribution under different Reynold numbers

Wang, Jing,Li, Shu-Cai,Li, Li-Ping,Gao, Cheng-Lu Techno-Press 2018 Geomechanics & engineering Vol.14 No.2

Water inrush through the destruction of water resisting rock mass structure was divided into direct water inrush, key block water inrush and splitting water inrush. In the direct water inrush, the Reynolds numbers has a significant effect on the distribution of the water flow and vortex occurred in the large Reynolds numbers. The permeability coefficient of the fracture is much larger than the rock, and the difference is between 104 and 107 times. The traditional theory and methods are not considering the effect of inertia force. In the position of the cross fracture, the distribution of water flow can only be linearly distributed according to the fracture opening degree. With the increase of Reynolds number, the relationship between water flow distribution and fracture opening is studied by Semtex.