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Search Results: 1 - 10 of 127075 matches for " Li Bingqian "
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A New Type High Power Lighting Emitting Diodes Based on MCPCB and its Opto-electrical Characteristics
基于金属线路板的新型大功率LED及其光电特性研究

Li Bingqian,
李炳乾

光子学报 , 2005,
Abstract: A new type of high power white LEDs (HPW-LEDs) based on metal core printed circuit board (MCPCB) and chip on board (COB) technique is designed and demonstrated, its opto-electrical characteristics are measured. The saturated characteristics of luminous flux is obvious at the forward current 800 mA (corresponding the forward power 3.3 mW), and the saturated characteristics of voltage-current is obvious until the forward current added to 800 mA, (corresponding the forward power 3.3 mW). These results show the MCPCB and COB technique could solve the problem of heat transfers very well, so the HPW-LEDs could work at a high level forward power. At the same time, the spectrum, luminous flux, and chromaticity coordinates of HPW-LEDs change with forward current are studied.
Preparation and Photocatalytic Properties of LnBaCo2O5+δ (Ln = Eu, Gd, and Sm)  [PDF]
Bingqian Han, Yuxiu Li, Nan Chen, Dongyang Deng, Xinxin Xing, Yude Wang
Journal of Materials Science and Chemical Engineering (MSCE) , 2015, DOI: 10.4236/msce.2015.34003
Abstract: A new type of photocatalytic material, double-perovskite oxides, LnBaCo2O5+δ (Ln = Eu, Gd, and Sm) was synthesized via a conventional solid-state reaction process using Ln2O3, BaCO3 and Co2O3 as raw materials. X-ray diffraction results show that the crystalline structures are a pure orthorhombic lattice and are consistent with LnBaCo2O5+δ microparticles. The photocatalytic activity of the LnBaCo2O5+δ (Ln = Eu, Gd, and Sm) powders was further demonstrated in the degradation of Congo red (CR) under ultraviolet light irradiation with the dye solution concentration of 25 or 50 mg·L-1. The double-perovskite oxides LnBaCo2O5+δ show a certain photocatalytic activity during the degradation of CR under ultraviolet light, which means that they are one kind of the promising photocatalytic materials for the degradation of the azo dyes.
Transgenic mice designed to express human α-1,2-fucosyltransferase in combination of human DAF and CD59 to avoid xenograft rejection
BingQian Liu,ChuanYu Cheng,YuDong Wu,JinXing Wei,GuangSan Li,TengXiang Ma
Science China Life Sciences , 2008, DOI: 10.1007/s11427-008-0019-7
Abstract: The expression of human α-1,2-fucosyltransferase (HT) or complement regulatory proteins has been proved as an strategy to overcome hypercute rejection in discordant xenogeneic organ transplantation. In this study, we examined whether peripheral blood mononuclear cells (PBMCs) from polytransgenic mice expressing the human HT, and complement regulatory proteins (DAF and CD59), can provide more effective protection against xenograft rejection. Transgenic mice were produced by co-injection of gene constructs for human HT, DAF and/or CD59. Flow Cytometry (FCM) was used to screen the positive transgenic mice. PBMCs from transgenic mice were incubated with 15% human serum to evaluate natural antibody binding, complement activation and expression of adhesion molecules. Three transgenes were strongly expressed in PBMCs of transgenic mice, and HT expression significantly reduced expression of the major xenoepitope galactose-α-1,3-galactose (α-Gal). Functional studies with PBMCs showed that co-expression of HT and DAF or CD59 markedly increased their resistance to human serum-mediated cytolysis when compared with single transgenic PBMCs. Moreover, the combined expression of triple transgenes in PBMCs led to the greatest protection against human serum-mediated cytolysis, avoided hyperacute rejection and reduced expression of adhesion molecules. Strong co-expression of triple transgenes was completely protected from xenograft hyperacute rejection and partially inhibited acute vascular rejection. The studies suggest that engineering mice to express triple molecules represents an critical step toward prolonging xenograft survival and might be more suitable for xenotransplantation.
Transgenic mice designed to express human α-1,2-fucosyltransferase in combination of human DAF and CD59 to avoid xenograft rejection

LIU BingQian,CHENG ChuanYu,WU YuDong,WEI JinXing,LI GuangSan &,MA TengXiang,

中国科学C辑(英文版) , 2008,
Abstract: The expression of human α-1,2-fucosyltransferase (HT) or complement regulatory proteins has been proved as an strategy to overcome hypercute rejection in discordant xenogeneic organ transplantation. In this study, we examined whether peripheral blood mononuclear cells (PBMCs) from polytransgenic mice expressing the human HT, and complement regulatory proteins (DAF and CD59), can provide more effective protection against xenograft rejection. Transgenic mice were produced by co-injection of gene constructs for human HT, DAF and/or CD59. Flow Cytometry (FCM) was used to screen the positive transgenic mice. PBMCs from transgenic mice were incubated with 15% human serum to evaluate natural antibody binding, complement activation and expression of adhesion molecules. Three transgenes were strongly expressed in PBMCs of transgenic mice, and HT expression significantly reduced expression of the major xenoepitope galactose-α-1,3-galactose (α-Gal). Functional studies with PBMCs showed that co-expression of HT and DAF or CD59 markedly increased their resistance to human serum-mediated cytolysis when compared with single transgenic PBMCs. Moreover, the combined expression of triple transgenes in PBMCs led to the greatest protection against human serum-mediated cytolysis, avoided hyperacute rejection and reduced expression of adhesion molecules. Strong co-expression of triple transgenes was completely protected from xenograft hyperacute rejection and partially inhibited acute vascular rejection. The studies suggest that engineering mice to express triple molecules represents an critical step toward prolonging xenograft survival and might be more suitable for xenotransplantation. Supported by the Doctor Initiation Foundation of Zhengzhou University.
OPTICAL CHARACTERISTICS AND OPTIMUM DESIGN OF OPTRICAL EXICITED SELF-RESONANT POLYSILICON SENSOR
光激光拾自谐振传感器的光学特性及优化设计

Li Bingqian,Zhu Changchun,Liu Junhua,
李炳乾
,朱长纯,刘君华

光子学报 , 2002,
Abstract: Multilayer model is established for self-resonant polysilicon sensor.Then,the optical characteristics of the sensor are analyse by this model in theoretical,and the thickness of the microbeam and the high of the cavity is optimized.
Optimization of polyethylenimine-mediated transient transfection using response surface methodology design
Fang,Qiangyi; Shen,Bingqian;
Electronic Journal of Biotechnology , 2010,
Abstract: response surface methodology was undertaken to optimize the polyethylenimine-mediated transient transfection of suspension cultured hek 293-f cells. a total of 15 combinations were designed according to box-behnken design to identify the effects of dna concentration, polyethylenimine concentration and incubation time on transient transfection efficiency. the highest integral optic density of green fluorescent protein presenting r-protein yield was accessed using a dna concentration of 1.75 μg/ml, a polyethylenimine concentration of 10.5 μg/ml, and an incubation time of 11.8 min. analysis of variance demonstrated that the experimental values fit well with a quadratic model. the rsm-optimized transient transfection resulted in greater production of human tissue prokallikrein (tprok) than non-rsm-optimized conditions: protein yield was 32.0 mg/l and the maximum viable cell density reached 3.57 x 106 cells/ml in a 5 l stirred-tank bioreactor culture.
Negative differential conductance in molecular junctions: an overview of experiment and theory
Bingqian Xu,Yonatan Dubi
Physics , 2015,
Abstract: One of the ultimate goals of molecular electronics is to create technologies that will complement - and eventually supersede - Si-based microelectronics technologies. To reach this goal, electronic properties that mimic at least some of the electrical behaviors of today's semiconductor components must be recognized and characterized. AN outstanding example for one such behavior is negative differential conductance (NDC), in which an increase in voltage across the device terminals results in a decrease in the electrical current passing through the device. This overview focuses on the NDC phenomena observed in metal-single molecule-metal junctions, and is roughly divided into two parts. In the first part, the central experiments which demonstrate NDC in single-molecule junctions are critically overviewed, with emphasis on the main observations and their possible physical origins. The second part is devoted to the theory of NDC in single-molecule junctions, where simple models are employed to shed light on possible mechanisms leading to NDC.
Effects of confined space and near vision stimulation on refractive status and vitreous chamber depth in adolescent rhesus monkeys
YunXia Leng,WeiZhong Lan,KeMing Yu,BingQian Liu,ZhiKuan Yang,Zheng Li,XingWu Zhong,ShaoChong Zhang,Jian Ge
Science China Life Sciences , 2010, DOI: 10.1007/s11427-010-4099-9
Abstract: This study aimed to investigate the effects of sustained near vision stimulation, on the refractive development and elongation of the vitreous chamber in adolescent rhesus monkeys. A total of 12 adolescent rhesus monkeys (1.5–2.0 years old) were randomly assigned to 3 groups. In groups A (n=4) and B (n=4), monkeys were reared in close-vision cages for 8 and 4 h d 1, respectively; tiny granules were added on the cage floor to avoid visual deprivation and to encourage near gaze. In group C (n=4), monkeys were reared in open-vision cages, with non-granule food as a control. Vitreous chamber depth, refractive status, and corneal refractive power were assessed over 18 months. Paired t-test was used to compare the differences and a P-value<0.05 was considered to be statistically significant. In group A, vitreous chamber depth and optical axis elongated significantly, and refractive error shifted towards myopia during the observation period. In group B, vitreous chambers and optical axis elongated but the refractive power did not show significant changes. In group C, there was no significant elongation in vitreous chambers and optical axis, and the refractive power changed slightly towards hypermetropia. There were no significant changes in corneal refractive power in each group. Sustained near vision can promote vitreous chamber growth and induce myopic shifts in refractive power in adolescent monkeys. Our results demonstrate the potential for a primate model of near-work-related myopia.
Serum Starvation Induced Cell Cycle Synchronization Facilitates Human Somatic Cells Reprogramming
Mengfei Chen, Jingjing Huang, Xuejiao Yang, Bingqian Liu, Weizhong Zhang, Li Huang, Fei Deng, Jian Ma, Yujing Bai, Rong Lu, Bing Huang, Qianying Gao, Yehong Zhuo, Jian Ge
PLOS ONE , 2012, DOI: 10.1371/journal.pone.0028203
Abstract: Human induced pluripotent stem cells (iPSCs) provide a valuable model for regenerative medicine and human disease research. To date, however, the reprogramming efficiency of human adult cells is still low. Recent studies have revealed that cell cycle is a key parameter driving epigenetic reprogramming to pluripotency. As is well known, retroviruses such as the Moloney murine leukemia virus (MoMLV) require cell division to integrate into the host genome and replicate, whereas the target primary cells for reprogramming are a mixture of several cell types with different cell cycle rhythms. Whether cell cycle synchronization has potential effect on retrovirus induced reprogramming has not been detailed. In this study, utilizing transient serum starvation induced synchronization, we demonstrated that starvation generated a reversible cell cycle arrest and synchronously progressed through G2/M phase after release, substantially improving retroviral infection efficiency. Interestingly, synchronized human dermal fibroblasts (HDF) and adipose stem cells (ASC) exhibited more homogenous epithelial morphology than normal FBS control after infection, and the expression of epithelial markers such as E-cadherin and Epcam were strongly activated. Futhermore, synchronization treatment ultimately improved Nanog positive clones, achieved a 15–20 fold increase. These results suggested that cell cycle synchronization promotes the mesenchymal to epithelial transition (MET) and facilitates retrovirus mediated reprogramming. Our study, utilization of serum starvation rather than additional chemicals, provide a new insight into cell cycle regulation and induced reprogramming of human cells.
Research on the Relationship of the Change in Forward Voltage with Temperature of Light Emitting Diode
LED正向压降随温度的变化关系研究

Li Bingqian,Bu Liangji,Gan Xiongwen,Fan Guanghan Foshan Nationstar OptoelectCo,Ltd,Foshan South China Normal University,Guangzhou Foshan Post Dr Work Station,Foshan,
李炳乾
,布良基,甘雄文,范广涵

光子学报 , 2003,
Abstract: Physical mechanism of the forward voltage changes with the operator temperature is analyzed in this paper, and a measurement system is built to research these changes. The linear fitted method is used to analyze the experiment data, and the coefficient of the forward voltage changes with temperature is gotten for many types light emitting diodes, it is very important parameter for the thermal control and device structure design of ultra high brightness, power LED devices and assemble.
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