http://chineseinput.net/에서 pinyin(병음)방식으로 중국어를 변환할 수 있습니다.
변환된 중국어를 복사하여 사용하시면 됩니다.
- 中文 을 입력하시려면 zhongwen을 입력하시고 space를누르시면됩니다.
- 北京 을 입력하시려면 beijing을 입력하시고 space를 누르시면 됩니다.
RISS 인기검색어
- 검색키워드
- 저자 : ( Jian Xu ) (검색결과 575 건)
- 무료
- 기관 내 무료
- 유료
-
-
-
Xu, Jian,Qin, Chuanxiang,Huang, Yanlin,Wang, Yaorong,Qin, Lin,Seo, Hyo Jin Elsevier 2017 APPLIED SURFACE SCIENCE - Vol.396 No.-
<P><B>Abstract</B></P> <P>Pure and V<SUP>5+</SUP>-doped Bi<SUB>6</SUB>Mo<SUB>2</SUB>O<SUB>15</SUB> (3Bi<SUB>2</SUB>O<SUB>3</SUB>·2MoO<SUB>3</SUB>) photocatalysts were synthesized through electrospinning, followed by low-temperature heat treatment. The samples developed into nanoparticles with an average size of approximately 50nm. The crystalline phases were verified via X-ray powder diffraction measurements (XRD). The surface properties of the photocatalysts were studied by scanning electron microscopy (SEM), transmission electron microscopy (TEM) and X-ray photoelectron spectroscopy (XPS) analyses. The UV–vis spectra showed that V doping in Bi<SUB>6</SUB>Mo<SUB>2</SUB>O<SUB>15</SUB> shifted the optical absorption from the UV region to the visible-light wavelength region. The energy of the band gap of Bi<SUB>6</SUB>Mo<SUB>2</SUB>O<SUB>15</SUB> was reduced by V doping in the lattices. The photocatalytic activities of the pure and V-doped Bi<SUB>6</SUB>Mo<SUB>2</SUB>O<SUB>15</SUB> were tested through photodegradation of rhodamine B (RhB) dye solutions under visible light irradiation. Results showed that 20 mol% V-doped Bi<SUB>6</SUB>Mo<SUB>2</SUB>O<SUB>15</SUB> achieved efficient photocatalytic ability. RhB could be degraded by V-doped Bi<SUB>6</SUB>Mo<SUB>2</SUB>O<SUB>15</SUB> in 2h. The photocatalytic activities and mechanisms were discussed according to the characteristics of the crystal structure and the results of EIS and XPS measurements.</P> <P><B>Highlights</B></P> <P> <UL> <LI> V<SUP>5+</SUP>-doped Bi<SUB>6</SUB>Mo<SUB>2</SUB>O<SUB>15</SUB> was synthesized by the electrospinning preparation. </LI> <LI> The band gap energy of Bi6Mo12O15 was greatly reduced by V-doping in the lattices. </LI> <LI> V-doped Bi<SUB>6</SUB>Mo<SUB>2</SUB>O<SUB>15</SUB> shows high activity in RhB degradation under visible light. </LI> <LI> Crystal structure of Bi<SUB>6</SUB>Mo<SUB>2</SUB>O<SUB>15</SUB> is favorable for high photocatalytic capacity. </LI> </UL> </P>
-
Mechanism of shear strength deterioration of loess during freeze-thaw cycling
Xu, Jian,Wang, Zhangquan,Ren, Jianwei,Yuan, Jun Techno-Press 2018 Geomechanics & engineering Vol.14 No.4
Strength of loess that experienced cyclic freeze and thaw is of great significance for evaluating stability of slopes and foundations in loess regions. This paper takes the frequently encountered loess in the Northwestern China as the study object and carried out three kinds of laboratory tests including freeze-thaw test, direct shear test and SEM test to investigate the strength behaviors of loess after cyclic freeze and thaw, and the correlation with meso-level changes in soil structure. Results show that for loess specimens at four dry densities, the cohesion decreases with freeze-thaw cycles until a residual value is reached and thus an exponential equation is proposed. Besides, little change in the angle of internal friction was observed as freeze-thaw proceeds. This may depend on the varying of soil structure, based on which a clue can be found from the surface morphology and mesoscopic scanning of loess specimens. Clearly we observed significant changes in surface morphology of loess and it tends to aggravate at higher water contents or more cycles of freeze and thaw. Moreover, freeze-thaw cycling leads to obvious changes in the meso-structure of loess including lowering the particle aggregates and increasing both the proportion of fine particles and porosity area ratio. A damage variable dependent on the ratio of porosity area is introduced based on the continuum damage mechanics and its correlation with cohesion is discussed.
-
Jian Xu,Fei Zhong,Yonghong Zhang,Jianlou Zhang,Shanshan Huo,Hongyu Lin,Liyue Wang,Dan Cui,Xiujin Li 아세아·태평양축산학회 2017 Animal Bioscience Vol.30 No.4
Objective: To generate recombinant Bacillus subtilis (B. subtilis) engineered for expression of porcine β-defensin-2 (pBD-2) and cecropin P1 (CP1) fusion antimicrobial peptide and investigate their anti-bacterial activity in vitro and their growth-promoting and disease resisting activity in vivo. Methods: The pBD-2 and CP1 fused gene was synthesized using the main codons of B. subtilis and inserted into plasmid pMK4 vector to construct their expression vector. The fusion peptide-expressing B. subtilis was constructed by transformation with the vector. The expressed fusion peptide was detected with Western blot. The antimicrobial activity of the expressed fusion peptide and the recovered pBD-2 and CP1 by enterokinase digestion in vitro was analyzed by the bacterial growth-inhibitory activity assay. To analyze the engineered B. subtilis on growth promotion and disease resistance, the weaned piglets were fed with basic diet supplemented with the recombinant B. subtilis. Then the piglets were challenged by enteropathogenic Escherichia coli (E. coli). The weight gain and diarrhea incidence of piglets were measured after challenge. Results: The recombinant B. subtilis engineered for expression of pBD-2/CP1 fusion peptide was successfully constructed using the main codons of the B. subtilis. Both expressed pBD-2/CP1 fusion peptide and their individual peptides recovered from parental fusion peptide by enterokinase digestion possessed the antimicrobial activities to a variety of the bacteria, including gram-negative bacteria (E. coli, Salmonella typhimurium, and Haemophilus parasuis) and gram-positive bacteria (Staphylococcus aureus). Supplementing the engineered B. subtilis to the pig feed could significantly promote the piglet growth and reduced diarrhea incidence of the piglets. Conclusion: The generated B. subtilis strain can efficiently express pBD-2/CP1 fusion antimicrobial peptide, the recovered pBD-2 and CP1 peptides possess potent antimicrobial activities to a variety of bacterial species in vitro. Supplementation of the engineered B. subtilis in pig feed obviously promote piglet growth and resistance to the colibacillosis.
-
Xu, Jian,Cao, Lei,Feng, Yongyi,Huang, Yanlin,Wang, Yaorong,Qin, Lin,Seo, Hyo Jin Elsevier 2017 Journal of luminescence Vol.183 No.-
<P><B>Abstract</B></P> <P>In<SUB>2</SUB>Si<SUB>2</SUB>O<SUB>7</SUB> is a known indium-based scintillator with fast ultraviolet photoluminescence. Unfortunately the emission only can be detected below 200K. the poor thermal stability limits its application at room temperature. In this work, the luminescence improvement of In<SUB>2</SUB>Si<SUB>2</SUB>O<SUB>7</SUB> was realized by F<SUP>−</SUP>-ions doping in the lattices. The ceramic phosphors were via typical solid-state reaction method. The pure crystalline phase with thortveirite-type structure was confirmed by X-ray diffraction (XRD) Rietveld refinements. The photoluminescence (PL) emission and excitation spectra together with the luminescence thermal stability were tested. The fluorescence decay curves CIE emission Stokes shifts were measured. The ceramic samples could present blue luminescence with maximum wavelength at about 340nm under the excitation of UV light or high energy X-ray irradiation. The pure sample only presents luminescence below 200K, however, the F-doping can be greatly enhance the luminescence thermal stability. The F-doped In<SUB>2</SUB>Si<SUB>2</SUB>O<SUB>7</SUB> could present emission signals with fast decay lifetime of 850ns at room temperature. The luminescence transitions from the In<SUP>3+</SUP>-O<SUP>2−</SUP> charge transfer (CT) were discussed on the structure properties.</P>
-
Reconstituted Fibril from Heterogenic Collagens-A New Method to Regulate Properties of Collagen Gels
Jian Yang,Haibo Wang,Lang He,Benmei Wei,Chengzhi Xu,Yuling Xu,Juntao Zhang,Sheng Li 한국고분자학회 2019 Macromolecular Research Vol.27 No.11
Heterotypic collagen fibril has long been found in the tissues of organisms, which plays an important role in the formation and function of complex structures of organisms. Inspiring by the phenomenon, scholars tried to incubate collagens from different sources into novel collagen materials in vitro, and the forming of heterogenic reconstituted collagen fibrils (RF) was often demonstrated by differential scanning calorimetry (DSC) and fluorescence quenching analysis. In this work, we used two type-I collagens from different species (bovine tendon and grasscarp fish skin) to coassemble in vitro, and verified the formation of RF from a new rheological perspective. In addition, we also investigated the assembly behavior, surface hydrophilicity and hydrophobicity, microscopic morphology and cell proliferation ability of the RF. The results showed that the assembly rate, surface properties, fibril size, viscoelastic properties of RF can be delicately regulated by the method of heterogenic collagen reconstitution. This study provides new experimental evidence for the reconstitution of heterogenic collagens, and also offers a new means for the regulation of collagen gel performance, which would help to expand the application range of collagen gel materials.
-
Xu, Lu-Wei,Qian, Ming,Jia, Rui-Peng,Xu, Zheng,Wu, Jian-Ping,Li, Wen-Cheng,Huang, Wen-Bin,Chen, Xing-Guo Asian Pacific Journal of Cancer Prevention 2012 Asian Pacific journal of cancer prevention Vol.13 No.4
The aim of this study was to investigate the expression and significance of microsomal prostaglandin synthase-1 (mPGES-1) and Beclin-1 in the development of prostate cancer (PCa). Immunohistochemistry was performed on paraffin-embedded sections with rabbit polyclonal against mPGES-1 and Beclin-1 in 40 PCa, 40 benign prostatic hyperplasia (BPH) and 10 normal prostate specimens for this purpose. Quantitative real-time polymerase chain reaction (qRT-PCR) was applied for mRNA expression of mPGES-1 and Beclin-1, while MTT assays were used to ascertain the best working concentration of the mPGES-1 inhibitor (CAY10526). The effect of CAY10526 treatment on expression of Beclin-1 in DU-145 cells was studied using Western blot analysis. Localization of Beclin-1 and mPGES-1 was in endochylema. Significant differences in expression was noted among PCa, BPH and normal issues (P<0.05). Beclin-1 expression inversely correlated with mPGES-1 expression in PCa tissue (P<0.05). CAY10526 could significantly block mPGES-1 expression and the proliferation of DU-145 cells (P<0.05), while increasing Beclin-1 levels (P<0.05). Overexpression of mPGES-1 could decrease the autophagic PCa cell death. Inhibiting the expression of mPGES-1 may lead to DU-145 cell death and up-regulation of Beclin-1. The results suggest that inhibition of mPGES-1 may have therapeutic potential for PCa in the future.
-
-
연관 검색어 추천
이 검색어로 많이 본 자료
활용도 높은 자료
