Eu³⁺ doped lutetium molybdenum oxides: Synthesis, optical properties, thermal behavior, and LED packaging

Cao, Chunyan,Xie, Along,Zhou, Tianliang,Zhong, Haichang,Lu, Xiangjun,Xie, An,Noh, Hyeon Mi,Jeong, Jung Hyun Elsevier 2020 Journal of luminescence Vol.217 No.-

<P><B>Abstract</B></P> <P>Some lutetium molybdenum oxides were synthesized through a solid-state reaction method. By adjusting the molar ratios of raw materials of Lu<SUB>2</SUB>O<SUB>3</SUB> (Eu<SUB>2</SUB>O<SUB>3</SUB>) to MoO<SUB>3</SUB>, Eu<SUP>3+</SUP> doped lutetium molybdenum oxides Lu<SUB>2</SUB>MoO<SUB>6</SUB>, Lu<SUB>2</SUB>Mo<SUB>2</SUB>O<SUB>9</SUB>, Lu<SUB>2</SUB>(MoO<SUB>4</SUB>)<SUB>3</SUB>, and Lu<SUB>6</SUB>MoO<SUB>12</SUB> were obtained. The materials were characterized by X-ray diffraction (XRD) patterns, scanning electron microscope (SEM) images, energy-dispersive spectra (EDS), diffuse reflection (DR) spectra, photoluminescence (PL) excitation and emission spectra, luminescence decay curves, and temperature dependent integrated emission spectra. Enhanced excitation and emission spectra were recorded at high temperatures. Possible energy transfer processes were proposed to explain the excitation and emission spectra. By combining some phosphors with near ultraviolet (NUV) chips, the obtained light emitting diodes (LEDs) gave red light under forward bias current. The results suggest that the obtained Eu<SUP>3+</SUP> doped lutetium molybdenum oxides have potential applications in phosphor converted based NUV LEDs.</P> <P><B>Highlights</B></P> <P> <UL> <LI> Eu<SUP>3+</SUP> doped Lu<SUB>2</SUB>MoO<SUB>6</SUB>, Lu<SUB>2</SUB>Mo<SUB>2</SUB>O<SUB>9</SUB>, Lu<SUB>2</SUB>(MoO<SUB>4</SUB>)<SUB>3</SUB>, and Lu<SUB>6</SUB>MoO<SUB>12</SUB> were obtained. </LI> <LI> The materials present different structures, morphologies, optical properties, and luminescece decay behaviors. </LI> <LI> Eu<SUP>3+</SUP> concentration dependent optical properties in Lu<SUB>2</SUB>MoO<SUB>6</SUB> were researched. </LI> <LI> Enhanced excitation and emission spectra were recorded under high temperatures in some materials. </LI> <LI> Red LEDs were obtained by packaging phosphors to NUV LED chips. </LI> </UL> </P>

Selection of reference genes for RT-qPCR analysis in Trichogramma chilonis (Hymenoptera: Trichogrammatidae)

Xie Lian-Cheng,Tian Jun-Ce,Lu Yan-Hui,Xu Hongxing,Zang Lian-Sheng,Lu Zhongxian,Jin Lin-Hong 한국응용곤충학회 2021 Journal of Asia-Pacific Entomology Vol.24 No.3

Trichogramma chilonis is an important natural enemy for control of various Lepidoperan crop pests. The biology of T. chilonis is well-studied, but the molecular mechanisms of this biology require further study. Screening suitable reference genes is a vital step for use of RT-qPCR to understand underlying molecular physiology. In the present study, nine candidate reference genes including elongation factor 2 (EF2), ribosomal proteins (RPS23, RPL13, and RPL44), malate dehydrogenase (MDH), eukaryotic translation initiation factor 3 subunit F (EIF3F), zinc finger protein 268 (ZFP268), muscle specific protein 20 (MP20), and ATP synthase subunit alpha (ATP5F1A) were evaluated at different conditions including development stage, diet, temperature, and insecticide treat ments. Four common algorithms (the Delta Ct method, geNorm, BestKeeper, and NormFinder) and RefFinder were used to analyze gene expression stability. Our results indicated that two reference genes used for normalization were sufficient, and the optimal combinations were: RPS23 and EF2 for developmental stages, ZFP268 and EF2 for feeding with different diets, ZFP268 and RPL13 for temperature treatments, and EF2 and RPL44 for insec ticide treatments. The results provide preliminary determination of suitable reference gene for standard RT-qPCR analyses in T. chilonis, which might establish the foundation for further molecular biology research.

Lack of Association Between the Matrix Metalloproteinase-2 -1306C>T Polymorphism and Breast Cancer Susceptibility: a Meta-analysis

Yang, Lu,Li, Ning,Wang, Siyu,Kong, Yanan,Tang, Hailin,Xie, Xinhua,Xie, Xiaoming Asian Pacific Journal of Cancer Prevention 2014 Asian Pacific journal of cancer prevention Vol.15 No.12

Background: Since inconsistent results have been reported regarding the relation between the matrix metalloproteinase-2 (MMP-2) -1306C>T polymorphism and susceptibility for breast cancer, we performed a meta-analysis to investigate the issue. Materials and Methods: An internet search of PubMed and EMBASE was performed to identify eligible studies. Pooled odds ratios (ORs) with their corresponding confidence intervals (CIs) were calculated to evaluate any association between MMP-2 -1306C>T polymorphism and breast cancer susceptibility. Results: Nine case-control studies were included in the meta-analysis, involving 9,858 cases and 10,871 controls. Overall, there was no evidence of any association between the MMP-2 -1306C>T polymorphism and breast cancer susceptibility in different genetic models (T-allele vs C-allele: OR=0.95, 95%CI, 0.82-1.10, p=0.49; TT vs CC: OR=1.03, 95%CI, 0.90-1.19, p=0.66; TT+TC vs CC: OR=0.93, 95%CI, 0.78-1.10, p=0.38; TT vs TC+CC: OR=1.02, 95%CI, 0.89-1.17, p=0.77). In the subgroup analysis by ethnicity, CC was associated with a significant increase in breast susceptibility among Latin-Americans in the dominant model (OR=0.61, 95%CI, 0.40-0.93, p=0.02), but the association disappeared in other models. No significant association was observed among Europeans, East Asians and others in different genetic models. In the subgroup analysis by their source of controls, no significant association between MMP-2 -1306C>T polymorphism and breast cancer susceptibility was noted among population-based studies and hospital-based studies in different genetic models. Conclusions: The results of this meta-analysis suggest that MMP-2 -1306C>T polymorphism is not associated with breast cancer susceptibility, although the association among Latin-Americans in the dominant model was significant.

Study on 3D Characterized Profile and Point Accuracies of Ground Micro-Pyramid-Structured Si Surface

Jin Xie,Yong-Xian Lu,Xu-Ran Liu,Yan-Jun Lu 한국정밀공학회 2013 International Journal of Precision Engineering and Vol. No.

It is very difficult to evaluate 3D profile accuracy of micro-machined surface due to the 3D characterization of its measured point cloud. Hence, three ideal point cloud models, which are grid point model, slash profile model and horizontal profile model, were constructed to register 3D measured point cloud of micro-machined surface and evaluate the accuracies of characterized profile and points. First, #400 and #600 diamond wheel V-tips were employed to fabricate non-integrated and integrated micro-pyramidstructured surfaces with 173 μm in depth and 0.865 in aspect ratio in Computer Numerical Control (CNC) grinding system,respectively; then a white light interferometer was utilized to measure the micro-ground surfaces; finally, registration accuracy and registration efficiency were investigated with regard to characterized profile and point accuracies. The results show that registration accuracy increases and registration efficiency decreases with increasing model point number, but they have little relation with the posture of measured point cloud. Registration error may converge to micro-ground form error when model point number is larger than measured point number. Moreover, the slash profile and horizontal profile models may register characterized profile and point more precisely than grid point model. The slash profile model can produce the best registration accuracy and efficiency. It is confirmed that the micro-ground form errors are 23.8 μm and 7.9 μm, the characterized profile errors are 37.2 μm and 19.0 μm and the characterized peak errors are 51.2 μm and 34.1 μm for non-integrated surface and integrated surface, respectively. As a result,a #600 diamond grinding wheel may be used to perform a precision micro-grinding in CNC grinding system.

Emodin-Provoked Oxidative Stress Induces Apoptosis in Human Colon Cancer HCT116 Cells through a p53-Mitochondrial Apoptotic Pathway

Xie, Mei-Juan,Ma, Yi-Hua,Miao, Lin,Wang, Yan,Wang, Hai-Zhen,Xing, Ying-Ying,Xi, Tao,Lu, Yuan-Yuan Asian Pacific Journal of Cancer Prevention 2014 Asian Pacific journal of cancer prevention Vol.15 No.13

Emodin, a natural anthraquinone isolated from the traditional Chinese medicine Radix rhizoma Rhei, can induce apoptosis in many kinds of cancer cells. This study demonstrated that emodin induces apoptosis in human colon cancer HCT116 cells by provoking oxidative stress, which subsequently triggers a p53-mitochondrial apoptotic pathway. Emodin induced mitochondrial transmembrane potential loss, increase in Bax and decrease in Bcl-2 expression and mitochondrial translocation and release of cytochrome c to cytosol in HCT116 cells. In response to emodin-treatment, ROS increased rapidly, and subsequently p53 was overexpressed. Pretreatment with the antioxidant NAC diminished apoptosis and p53 overexpression induced by emodin. Transfecting p53 siRNA also attenuated apoptosis induced by emodin, Bax expression and mitochondrial translocation being reduced compared to treatment with emodin alone. Taken together, these results indicate that ROS is a trigger of emodin-induced apoptosis in HCT116 cells, and p53 expression increases under oxidative stress, leading to Bax-mediated mitochondrial apoptosis.

A Corpus-Based Longitudinal Study of Diction in Chinese and British News Reports on Chang'e Project

Lu, Rong,Xie, Xue,Qi, Jiashuang,Ali, Afida Mohamad,Zhao, Jie Institute for Corpus Research 2022 Asia pacific journal of corpus research Vol.3 No.1

As a milestone progression in China's space exploration history, Chang'e Project has attracted a lot of media attention since its first launching. This study aims to examine and compare the similarities and differences between the Chinese media and the British media in using nouns, verbs, and adjectives to report the Chang'e Project. After categorising the documents based on specific project phases, we created two diachronic corpora to explore the linguistic shifts and similarities and differences of diction employed by the Chinese and British media on the Chang'e Project ideology. This longitudinal study was performed with Lancsbox and the CLAWS web tagger through critical discourse analysis as the theoretical framework. The findings of the current study showed that the Chang'e Project coverage in both media increased on an annual basis, especially after 2019. In contrast to the objectivity and positivity in the Chinese Media, the British Media seemed to be more subjective with more appraisal adjectives in the news reports. Nonetheless, both countries were trying to be objective and formal in choosing nouns and verbs. Ideology-wise, the Chinese news media reports portrayed more positivity on domestic circumstances while the British counterpart was typically more critical. Notably, the study outcomes could catalyse future research on the Chang'e Project and facilitate diplomatic policies.

Preparation and Characterization of Sisal Fiber-based Activated Carbon by Chemical Activation with Zinc Chloride

Lu, Xincheng,Jiang, Jianchun,Sun, Kang,Xie, Xinping Korean Chemical Society 2014 Bulletin of the Korean Chemical Society Vol.35 No.1

Sisal fiber, an agricultural resource abundantly available in china, has been used as raw material to prepare activated carbon with high surface area and huge pore volume by chemical activation with zinc chloride. The orthogonal test was designed to investigate the influence of zinc chloride concentration, impregnation ratio, activation temperature and activation time on preparation of activated carbon. Scanning electron micrograph, Thermo-gravimetric, $N_2$-adsorption isotherm, mathematical models such as t-plot, H-K equation, D-R equation and BJH methods were used to characterize the properties of the prepared carbons and the activation mechanism was discussed. The results showed that $ZnCl_2$ changed the pyrolysis process of sisal fiber. Characteristics of activated carbon are: BET surface area was $1628m^2/g$, total pore volume was $1.316m^3/g$ and ratio of mesopore volume to total pore volume up to 94.3%. These results suggest that sisal fiber is an attractive source to prepare mesoporous high-capacity activated carbon by chemical activation with zinc chloride.

Anti-tumor Effects and Apoptosis Induction by Realgar Bioleaching Solution in Sarcoma-180 Cells in Vitro and Transplanted Tumors in Mice in Vivo

Xie, Qin-Jian,Cao, Xin-Li,Bai, Lu,Wu, Zheng-Rong,Ma, Ying-Ping,Li, Hong-Yu Asian Pacific Journal of Cancer Prevention 2014 Asian Pacific journal of cancer prevention Vol.15 No.6

Background: Realgar which contains arsenic components has been used in traditional Chinese medicine (TCM) as an anticancer drug. However, neither Realgar nor its formula are soluble in water. As a result, high dose of Realgar has to be administered to achieve an effective blood medicine concentration, and this is associated with adverse side effects. The objective of the present study was to increase the solubility of a formula using hydrometallurgy technology as well as investigating its effects on in vitro and in vivo cell proliferation and apoptosis in Sarcoma-180 cell line. Materials and Methods: Antiproliferative activity of Realgar Bioleaching Solution (RBS) was evaluated by MTT assay. Further, effects of RBS on cell proliferation and apoptosis were studied using flow cytometry and transmission electron microscopy. Kunming mice were administered RBS in vivo, where arsenic specifically targeted solid tumors. Results: The results indicated that RBS extract potently inhibited the tumor growth of Sarcoma-180 cell line in a dose-dependent manner. Flow cytometry and transmission electron microscopy further indicated that RBS significantly induced cell apoptosis through the inhibition of cell cycle pathway in a dose-dependent manner. Further, on RBS administration to mice, arsenic was specifically targeted to solid tumor.s Conclusions: RBS could substitute for traditional Realgar or its formula to work as a potent tool in cancer treatment.

Amperometric Immunosensor for Myeloperoxidase in Human Serum Based on a Multi-wall Carbon Nanotubes-Ionic Liquid-Cerium Dioxide Film-modified Electrode

Lu, Lingsong,Liu, Bei,Liu, Chenggui,Xie, Guoming Korean Chemical Society 2010 Bulletin of the Korean Chemical Society Vol.31 No.11

A label-free amperometric immunosensor has been proposed for the detection of myeloperoxidase (MPO) in human serum. To fabricate such an immunosensor, a composite film consisting of N,N-dimethylformamide (DMF), multiwall carbon nanotubes (MWCNTs) and 1-ethyl-3-methyl imidazolium tetrafluoroborate ($EMIMBF_4$) suspension was initially formed on a glassy carbon electrode (GCE). Then cerium dioxide ($CeO_2$) dispersed by chitosan was coated on the GCE. After that, MPO antibodies (anti-MPO) were attached onto the nano$CeO_2$ surface. With a noncompetitive immunoassay format, the antibody-antigen complex formed between the immobilized anti-MPO and MPO in sample solution. The immunosensor was characterized by cyclic voltammetry, transmission electron microscopy (TEM) and scanning electron microscopy (SEM). The factors influencing the performance of the immunosensor were studied in detail. Under optimal conditions, the current change before and after the immunoreaction was proportional to MPO concentration in the range of 5 to $300\;ng\;mL^{-1}$ with a detection limit of $0.2\;ng\;mL^{-1}$.

A new bismuth vanadate photocatalyst of Bi₂₃V₄O_44.5 nanoplates with layered δ-Bi₂O₃ based fluorite-type superstructures

Lu, Yuting,Chen, Luyang,Li, Yuze,Xie, Hongde,Cheng, Han,Jin Seo, Hyo Elsevier 2016 Materials letters Vol.164 No.-

<P><B>Abstract</B></P> <P>The work reports the large-scale synthesis and photocatalytic activity of Bi<SUB>23</SUB>V<SUB>4</SUB>O<SUB>44.5</SUB> nanoplates. The structural refinement was conducted in the layered δ-Bi<SUB>2</SUB>O<SUB>3</SUB> based superstructuLre. The detailed surface properties were characterized. Bi<SUB>23</SUB>V<SUB>4</SUB>O<SUB>44.5</SUB> shows efficient absorption in visible region with a band-gap of 2.384eV from the hybridization of Bi-6s and O-2p orbitals. Particularly, Bi<SUB>23</SUB>V<SUB>4</SUB>O<SUB>44.5</SUB> shows an efficient photodegradation for methylene blue (MB). The photocatalysis benefits from the layered B–O structure characteristic and the codoped defects of V<SUP>4+</SUP>/V<SUP>5+</SUP> ions in the lattices. Bi<SUB>23</SUB>V<SUB>4</SUB>O<SUB>44.5</SUB> nanoplates could be a potential photocatalyst.</P> <P><B>Highlights</B></P> <P> <UL> <LI> Bi<SUB>23</SUB>V<SUB>4</SUB>O<SUB>44.5</SUB> nanoplates were prepared by the Pechini method. </LI> <LI> It has a narrow band-gap of 2.384eV from hybridization of Bi-6s and O-2p. </LI> <LI> Bi<SUB>23</SUB>V<SUB>4</SUB>O<SUB>44.5</SUB> has photocatalysis report visible-light-irradiation. </LI> <LI> Photocatalysis is due to layered δ-Bi<SUB>2</SUB>O<SUB>3</SUB>-like structure and codoped V<SUP>4+</SUP>/V<SUP>5+</SUP> ions. </LI> </UL> </P>