SYNTHESIS AND FLUORESCENCE PROPERTIES OF LaF 3 :Tb 3 þ PHOSPHORS VIA ULTRASONIC- ASSISTED IONIC LIQUID METHOD

LING ZHU,XUEQIANG CAO,SANXI LIU,YU HUI,BINGLIN ZOU 성균관대학교(자연과학캠퍼스) 성균나노과학기술원 2014 NANO Vol.9 No.7

Hexagonal phase LaF 3 :Tb 3 þnano/microcrystals were successfully synthesized via ultrasonic-assisted ionic liquid (IL) method. The ¯eld emission scanning electron microscope (FESEM)images revealed that the morphologies of the as-prepared LaF 3 :Tb 3 þsamples were graduallyconverted from nanoplates to microcylinders with increasing the concentration of Tb 3 þions. Thephotoluminescent (PL) spectrum shows that all the as-prepared La 1 ?xTbxF 3 samples show thecharacteristic emissions of Tb 3 þ 5D4 ! 7FJ (J ¼ 6-3, with 5D4 ! 7F5 green emission at 542 nmas the strongest one) transitions. The optimal Tb 3 þ-doped concentration is 20 mol.% in the LaF 3host. The photoluminescence intensity of the La 0 : 80 Tb 0 : 20 F 3 microcylinders prepared by ultra-sonic irradiation was largely improved as compared with that of the product prepared by stirring.

Effects of cellulose, hemicellulose and lignin on biomass pyrolysis kinetics

Lingli Zhu,Zhaoping Zhong 한국화학공학회 2020 Korean Journal of Chemical Engineering Vol.37 No.10

In order to investigate interactions among biomass components on pyrolysis kinetics, pyrolysis experiments of individual components, synthetic biomass (designed by Design-Export software) and natural biomass (rice husk and corn straw) were conducted on a thermogravimetric analyzer (TGA). The results revealed that the pyrolysis behavior of cellulose is sharp, which is with low pyrolysis reaction order (1.38), high activation energy (168.61 kJ/mol) and high pre-exponential factor (3.50E+12 /s). The pyrolysis behavior of hemicellulose and lignin is slower but more complicated, both with high pyrolysis reaction order (2.30, 1.51), low activation energy (126.31, 87.21 kJ/mol), and low pre-exponential factor (9.67E+09, 2.59E+05 /s). Comparison of the experimental and calculated kinetics of synthetic samples confirmed that interactive effects on pyrolysis kinetics exist in the co-pyrolysis process. In particular, the presence of lignin inhibited the pyrolysis reaction rate of synthetic biomass, and cellulose played the dominant role in the activation energy and frequency factor. The pyrolysis reaction order was strongly influenced by hemicellulose owing to its abundant and complex branched chains. The predicted model was also established for calculating kinetic parameters of natural biomass with known proportions of three components. The predicted results were consistent with the experimental ones, validating the effectiveness of the prediction model.

Persistent Anxiety Is Associated with Higher Glycemia Post-Transition to Adult Services in Asian Young Adults with Diabetes

Ling Zhu,Suresh Rama Chandran,Wee Boon Tan,Xiaohui Xin,Su-Yen Goh,Daphne Su-Lyn Gardner 대한당뇨병학회 2021 Diabetes and Metabolism Journal Vol.45 No.1

Background There is little longitudinal information on psychological burden and metabolic outcomes in young adults with diabetes (YAD) in Asia. We aimed to evaluate the association between psychological status and glycemia at baseline and 2 years following transition in a cohort of YAD in Singapore. Methods Subjects with type 1 diabetes mellitus (T1DM) and type 2 diabetes mellitus (T2DM), aged 17 to 25 years, were recruited from the YAD clinic in Singapore General Hospital. The Hospital Anxiety and Depression and Problem Areas for Diabetes scales were administered at transition (baseline) and at 18 to 24 months. Glycosylated hemoglobin (HbA1c) assessed during routine visits was tracked longitudinally. Results A total of 98 T1DM (74.8%) and 33 T2DM (25.2%) subjects were recruited between January 2011 and November 2017. At baseline, mean HbA1c was 8.6%±1.7%. Only 26.0% achieved HbA1c of ≤7.5% and 16.8% achieved HbA1c of <7%. At baseline, prevalence of anxiety was 29.8%. At 24 months, 14.1% had persistent anxiety. Those with persistent anxiety had the highest mean HbA1c, particularly at 6 months (persistently anxious vs. persistently non-anxious: 9.9%±1.2% vs. 8.2%±1.9%, P=0.009). At baseline, 9.2% of subjects had depression. This group also had poorer glycemia at baseline (HbA1c of depressed vs non-depressed: 9.6%±2.1% vs. 8.5%±1.6%, P=0.04), which persisted up to 24 months. Conclusion The majority of YAD in Singapore have suboptimal glycemia. Psychological distress is a critical harbinger of poorer metabolic outcomes.

Performance and Design of Shear Connectors in Composite Beams with Parallel Profiled Sheeting at Elevated Temperatures

Ling-Zhu Chen,Gianluca Ranzi,Shou-Chao Jiang,Faham Tahmasebinia,Guo-Qiang Li 한국강구조학회 2016 International Journal of Steel Structures Vol.16 No.1

This paper describes an extensive experimental and numerical study conducted to evaluate the thermo-structural response of shear connectors embedded in composite slabs with steel sheeting parallel to the steel beam, with particular focus on opentrapezoidal profiles. For this purpose, eight push-out tests were carried out at different levels of temperature. A threedimensional finite element model was developed in Abaqus and its accuracy was validated against the experimental measurements collected as part of this study. The model was then used to perform a parametric study to gain insight into the structural response at different temperatures. The experimental and numerical results were then used to evaluate the accuracy of available European guidelines for predicting the capacity of shear connectors at elevated temperatures (when embedded in composite slabs with the profiled sheeting parallel to the steel beam). Finally, a new design equation was proposed to calculate the degradation factor defining the resistance of shear connectors for different levels of temperature

Printing performance of 3D printing cement-based materials containing steel slag

Zhu, Lingli,Yang, Zhang,Zhao, Yu,Wu, Xikai,Guan, Xuemao Techno-Press 2022 Advances in concrete construction Vol.13 No.4

3D printing cement-based materials (3DPCBM) is an innovative rapid prototyping technology for construction materials. This study is tested on the rheological behavior, printability and buildability of steel slag (SS) content based on the extrusion system of 3D printing. 0, 8 wt%, 16 wt%, 24 wt%, 32 wt% and 40 wt% SS was replaced cement, The test results revealed that the addition of SS would increase the fluidity of the printed paste, prolong the open time and setting time, reduce the plastic viscosity, dynamic yield stress and thixotropy, and is beneficial to improve the pumping and extrudability of 3DPCBM. With the increase of SS content, the static yield stress developed slowly with time which indicated that SS is harmful to the buildability of printing paste. The content of SS in 3DPCBM can reach up to 40% at most under the condition of satisfying rheological property and buildability, it provides a reference for the subsequent introduction of SS and other industrial solid waste into 3DPCBM by explored the influence law of SS on the rheological properties of 3DPCBM.

Biochemistry : PpsA, TufA, and Glutaminase Were Modulated under Yop Secretion Conditions in Yersinia enterocolitica

Ling Zhu Meng,Seung Hwan Yang,Tae Jong Kim,Joo Won Suh 한국응용생명화학회 2010 Applied Biological Chemistry (Appl Biol Chem) Vol.53 No.5

Yersinia enterocolitica expresses the Ysc type III secretion system (TTSS) for delivery of effector proteins (Yops) to host cells to manipulate immune system of the host. The study on the physiological change of Y. enterocolitica is important in determinin

Paeoniflorin attenuates atRAL-induced oxidative stress, mitochondrial dysfunction and endoplasmic reticulum stress in retinal pigment epithelial cells via triggering Ca2+/CaMKII-dependent activation of AMPK

Xue Zhu,Ke Wang,Fanfan Zhou,Ling Zhu 대한약학회 2018 Archives of Pharmacal Research Vol.41 No.10

Abnormal accumulation of the free-form alltrans- retinal (atRAL), a major intermediate of human visual cycle, is considered to be a key cause of retinal pigment epithelial (RPE) dysfunction in the pathogenesis of retinal degenerative diseases such as age-related macular degeneration (AMD). Paeoniflorin (PF), a monoterpene glucoside isolated from Paeonia lactiflora Pall., has been used in clinical treatment of retinal degenerative diseases in China for several years; however, the underlying mechanism remains unclear. The aim of this study is to investigate the protective effect of PF against atRAL toxicity in human ARPE-19 cells and its molecular mechanism. The results of our study showed that the pre-treatment of PF dose-dependently attenuated atRAL-induced cell injury by the reduction of Nox1/ROS-associated oxidative stress, mitochondrial dysfunction and GRP78-PERK-eIF2a- ATF4-CHOP-regulated endoplasmic reticulum (ER) stress in ARPE-19 cells. Additionally, our data showed that PF mainly exerted its activity via triggering calcium-calmodulin dependent protein kinase II (CaMKII)-mediated activation of AMP-activated protein kinase (AMPK). AMPK inhibition significantly reversed the protective effect of PF against atRAL toxicity in ARPE-19 cells. Overall, our findings provided the novel mechanism of PF protecting human RPE cells, which may prevent the progression of retinal degenerative diseases.

First-Principles Study of the Elastic, Hardness and Electronic Properties of MoAlB under High Pressure

Xiao Ling Zhu,Wei Yang,Shan Shan Gao,Jin Ping Zhang 한국물리학회 2019 THE JOURNAL OF THE KOREAN PHYSICAL SOCIETY Vol.74 No.5

The structure, elastic and electronic properties of MoAlB have been studied under high pressure by using first principles. The optimized lattice parameters, elastic constants, bulk moduli, and shear moduli agree well with experimental and other theoretical values. The relationships of the lattice constants with pressure indicated an anisotropic behavior. The calculated elastic constants satisfy the mechanical stability conditions. Our calculated Vickers hardness of MoAlB is 11.56~GPa, which agrees with the experimental data and confirms its having a relatively softer nature than the other borides. The Cauchy pressure, the Poisson's ratio and the $G/B$ value suggest that MoAlB is a brittle solid under ambient conditions, but the brittleness decreases with increasing pressure. The band structure and the density of states reveal the metallic feature of MoAlB, and the energy levels shift toward both sides of the Fermi level with increasing pressure. The Mulliken population and density of states suggest a mixture bonding nature of covalence and metallicity in MoAlB.

Triterpenoid saponins from Clinopodium chinense (Benth.) O. Kuntze and their biological activity

Yin-Di Zhu,Jing-Yi Hong,Feng-Da Bao,Na Xing,Ling-Tian Wang,Zhong-Hao Sun,Yun Luo,Hai Jiang,Xudong Xu,Nai-Liang Zhu,Hai-Feng Wu,Gui-Bo Sun,Jun-Shan Yang 대한약학회 2018 Archives of Pharmacal Research Vol.41 No.12

Four new ursane-type triterpenoid saponins, clinopoursaponins A–D (1–4), six new oleanane-type triterpenoid saponins, clinopodiside VII–XII (5–10), as well as eight known triterpene analogues (11–18), were isolated from the aerial parts of Clinopodium chinense (Benth.) O. Kuntze. The structures of the new compounds were determined based on extensive spectral analyses, including 1D (1H and 13C) and 2D NMR experiments (COSY, NOESY, HSQC, 2D TOCSY, HSQC-TOCSY and HMBC), HR-ESI-MS and chemical methods. Compounds 1–18 were evaluated for their protective effects against anoxia/reoxygenation-induced apoptosis in H9c2 cells and cytotoxicities against murine mammary carcinoma cell line 4T1. Compounds 8, 9 and 18 exhibited significant protective effects, while compound 1 exhibited cytotoxic activity with IC50 value of 7.4 μm compared to 7.6 μm for the positive control 10-hydroxycamptothecin.

Expression of Endogenous Hypoxia Markers in Vulvar Squamous Cell Carcinoma

Li, Yu-Zhu,Li, Shu-Ling,Li, Xia,Wang, Li-Jie,Wang, Jiu-Ling,Xu, Jia-Wen,Wu, Zhi-Hong,Gong, Li,Zhang, Xiao-Dan Asian Pacific Journal of Cancer Prevention 2012 Asian Pacific journal of cancer prevention Vol.13 No.8

Objective: To investigate the expression of endogenous hypoxia-related markers identified as being involved in vulvar squamous cell carcinoma (VSCC). Methods: We performed immunohistochemical staining of hypoxia-inducible factor-$1{\alpha}$ (HIF-$1{\alpha}$), glucose transporter-1 (GLUT-1), carbonic anhydrase 9 (CA-9) and vascular endothelial growth factor (VEGF), on tissue sections of 25 VSCC patients, 10 vulvar intraepithelial neoplasia (VIN) patients and 12 healthy controls. Results: HIF-$1{\alpha}$ expression was found in all sections, with no significant difference between controls, VIN and VSCC sections (all P<0.05). Glut-1 expression was found in 25% of control, 90% of VIN and 100% of VSCC sections. A significant difference between control and VIN or VSCC was observed (all P<0.05), while no difference was found between VIN and VSCC sections (P>0.05). CA-9 expression was negative in control sections, but it was found in 30% of VIN sections and 52% of VSCC sections with strong staining. Similarly, CA-9 expression also showed obvious differences between controls and VIN or VSCC sections (all P<0.05). However, there was no significant difference between VIN and VSCC (P>0.05). There were only 25% of control sections with weak VEGF expression, while strong staining was found in about 60% of VIN sections and 25% of VSCC sections (all P<0.05). In addition, a difference was also found between VIN and VSCC sections (P<0.05). Conclusion: Expression of endogenous hypoxia markers (HIF-$1{\alpha}$, GLUT-1, CA-9 and VEGF) might be involved in the malignant progression of VSCC.