A New BODIPY Derivative Bearing Piperazine Group

Qi, Xin,Kim, Sook-Kyung,Jun, Eun-Jin,Xu, Li,Kim, Sung-Jin,Yoon, Ju-Young Korean Chemical Society 2007 Bulletin of the Korean Chemical Society Vol.28 No.12

A new BODIPY derivative bearing piperazine group was synthesized and its fluorescent changes towards metal ions as well as pH are studied. The title compound displayed a moderate selectivity for Hg2+ among the metal ions examined.

A Comparison between Traditional and Modern Ethics from the Perspective of Social Philosophy

( Xin Qi Jia ) , ( Wan Fu Xi ) 한국윤리학회 2014 倫理硏究 Vol.95 No.1

Social philosophy is the study of people`s conception of basic social objectives. It can be divided into two categories based on two different basic objectives: harmony and strength. Harmony-oriented social philosophy and strength-oriented social philosophy are dominant in traditional society and modern society respectively. From the perspective of social philosophy, we can understand better the differences between traditional ethics and modern ethics.

Study on the BODIPY-triazine-based tripod fluorescent systems: various structures from similar procedure

Qi, Xin,Kim, Sook Kyung,Han, Su Jung,Xu, Li,Jee, Ah Young,Na Kim, Ha,Lee, Chongmok,Kim, Youngmee,Lee, Minyung,Kim, Sung-Jin,Yoon, Juyoung Informa UK (TaylorFrancis) 2009 Supramolecular chemistry Vol.21 No.6

Sitagliptin attenuates endothelial dysfunction independent of its blood glucose controlling effect

Xin-Miao Chang,Fei Xiao,Qi Pan,Xiao-Xia Wang,Li-Xin Guo 대한생리학회-대한약리학회 2021 The Korean Journal of Physiology & Pharmacology Vol.25 No.5

Although the contributions of sitagliptin to endothelial dysfunction in diabetes mellitus were previously reported, the mechanisms still undefined. Autophagy plays an important role in the development of diabetes mellitus, but its role in diabetic macrovascular complications is unclear. This study aims to observe the effect of sitagliptin on macrovascular endothelium in diabetes and explore the role of autophagy in this process. Diabetic rats were induced through administration of high-fat diet and intraperitoneal injection of streptozotocin. Then diabetic rats were treated with or without sitagliptin for 12 weeks. Endothelial damage and autophagy were measured. Human umbilical vein endothelial cells were cultured either in normal glucose or in high glucose medium and intervened with different concentrations of sitagliptin. Rapamycin was used to induce autophagy. Cell viability, apoptosis and autophagy were detected. The expressions of proteins in c-Jun N-terminal kinase (JNK)-Bcl-2-Beclin-1 pathway were measured. Sitagliptin attenuated injuries of endothelium in vivo and in vitro. The expression of microtubuleassociated protein 1 light chain 3 II (LC3II) and beclin-1 were increased in aortas of diabetic rats and cells cultured with high-glucose, while sitagliptin inhibited the over-expression of LC3II and beclin-1. In vitro pre-treatment with sitagliptin decreased rapamycin-induced autophagy. However, after pretreatment with rapamycin, the protective effect of sitagliptin on endothelial cells was abolished. Further studies revealed sitagliptin increased the expression of Bcl-2, while inhibited the expression of JNK in vivo. Sitagliptin attenuates injuries of vascular endothelial cells caused by high glucose through inhibiting over-activated autophagy. JNK-Bcl-2-Beclin-1 pathway may be involved in this process.

Abundant Manganese Complex-Anchored BiOI Hybrid Photocatalyst for Visible Light-Driven CO2 Reduction

Xin Xin,Ning Ma,Changying Hu,Qi Liang,Zhaoyong Bian 성균관대학교(자연과학캠퍼스) 성균나노과학기술원 2019 NANO Vol.14 No.2

An abundant manganese complex-anchored BiOI hybrid system for CO2 photocatalytic conversion was constructed. Layered BiOI and tricarbonyl Mn bipyridyl complex with carboxyl acid groups were connected with covalent bonds and used as visible light antenna and CO2 reduction reaction centers, respectively. The covalent connection of this hybrid system benefits the transfer of electrons from the semiconductor to the Mn complex. The anchoring group (carboxyl) is the key to CO2 reduction for the direct coupling of the two units, facilitating the transfer of electrons from BiOI to the manganese complexes. The photocatalytic properties and stability of the tri-carbonyl Mn–bipyridyl complex were significantly enhanced with the aid of anchored BiOI. A high turnover number (TON = 74) of HCOO- formation from CO2 could be achieved using this hybrid system under visible light irradiation.

Utilization of electron beam to modulate electron injection over Schottky barrier

Qi Zhang,Junjie Qi,Yunhua Huang,Huifeng Li,Xin Li,Ruoshui Wang,Yue Zhang 한국물리학회 2011 Current Applied Physics Vol.11 No.3

Modulation of electron injection over Schottky barrier was realized by employing electron beam irradiation on the metal/ZnO-nanowire contact. The structure revealed a good response to the illumination at a scanning frequency of 0.1 Hz, which can be enhanced by increasing bias and decreased with the increase of electron beam energy. These phenomena can be attributed to the Schottky barrier formed at the metal/ZnO-nanowire interface which limits the electron transport across the contact. The electron beam irradiation gives rise to high efficiency of electron injection over the barrier, while the interplay between charge discreteness, coherent scattering, and Coulomb interaction may reduce the conductivity.

Bond-Orientational Order in Melting of Colloidal Crystals

Xin Qi,Yong Chen,Yan Jin,Yao-Hui Yang 한국물리학회 2006 THE JOURNAL OF THE KOREAN PHYSICAL SOCIETY Vol.49 No.4

Using Brownian dynamics simulation, we study the orientational order in the melting transition of a colloidal system with a `soft' Yukawa potential. The bond-orientational order parameter ⓒ6 and the bond-orientational order function gB(r) are calculated in two-dimensional systems. We found that a two-stage transition and a hexatic phase indeed exist in two-dimensional melting, which is consistent with the prediction of the Kosterlitz-Thouless-Halperin-Nelson-Young theory. For comparing with the melting process in three-dimensional systems, we introduce the probability distribution of the single-particle local-order parameter. Based on extensive simulations, the break- down of local order is qualitatively suggested only to occur on the fractional part of the colloidal system for the two-dimensional melting, but in three-dimensional melting, that breakdown takes place on the whole system at the same time.F

Synthesis, second-harmonic generation (SHG), and photoluminescence (PL) properties of noncentrosymmetric bismuth selenite solid solutions, Bi_2-<i>x</i>Ln_<i>x</i>SeO₅ (Ln = La and Eu; <i>x</i> = 0–0.3)

Qi, Hai-Xin,Jo, Hongil,Oh, Seung-Jin,Ok, Kang Min Elsevier 2018 SOLID STATE SCIENCES Vol.76 No.-

<P><B>Abstract</B></P> <P>A series of La<SUP>3+</SUP> or Eu<SUP>3+</SUP>-doped noncentrosymmetric (NCS) bismuth selenite solid solutions, Bi<SUB>2-<I>x</I> </SUB>Ln<SUB> <I>x</I> </SUB>SeO<SUB>5</SUB> (<I>x</I> = 0.1, 0.2, and 0.3), have been successfully synthesized via standard solid-state reactions under vacuum with Bi<SUB>2</SUB>O<SUB>3</SUB>, La<SUB>2</SUB>O<SUB>3</SUB> (or Eu<SUB>2</SUB>O<SUB>3</SUB>), and SeO<SUB>2</SUB> as starting materials. Crystal structures and phase purities of the resultant materials were thoroughly characterized by powder X-ray diffraction using the Rietveld method. The results clearly show that the reported materials crystallize in the orthorhombic space group, <I>Abm</I>2 (No. 39), and exhibit pseudo-three-dimensional frameworks consisting of BiO<SUB>3</SUB>, BiO<SUB>5</SUB>, and SeO<SUB>3</SUB> polyhedra that share edges and corners. Detailed diffraction studies indicate that the cell volume of Bi<SUB>2-<I>x</I> </SUB>Ln<SUB> <I>x</I> </SUB>SeO<SUB>5</SUB> decreases with an increasing amount of Ln<SUP>3+</SUP> on the Bi<SUP>3+</SUP> sites. However, no ordering between Ln<SUP>3+</SUP> and Bi<SUP>3+</SUP> was observed in the Bi<SUB>2-<I>x</I> </SUB>Ln<SUB> <I>x</I> </SUB>SeO<SUB>5</SUB> solid solutions. Powder second-harmonic generation (SHG) measurements, using 1064 nm radiation, reveal that SHG efficiencies of Bi<SUB>2-<I>x</I> </SUB>Ln<SUB> <I>x</I> </SUB>SeO<SUB>5</SUB> solid solutions continuously decrease as more Ln<SUP>3+</SUP> cations are added to the sites of polarizable Bi<SUP>3+</SUP> cations. Photoluminescence (PL) measurements on Bi<SUB>2-<I>x</I> </SUB>Eu<SUB> <I>x</I> </SUB>SeO<SUB>5</SUB> exhibit three specific emission peaks at 592, 613, and 702 nm (<SUP>5</SUP>D<SUB>0</SUB> → <SUP>7</SUP>F<SUB>1, 2, 4</SUB>) owing to the 4f-4f intrashell transitions of Eu<SUP>3+</SUP> ions.</P> <P><B>Highlights</B></P> <P> <UL> <LI> New selenite solid solutions, Bi<SUB>2-<I>x</I> </SUB>Ln<SUB> <I>x</I> </SUB>SeO<SUB>5</SUB> (Ln = La and Eu; <I>x</I> = 0–0.3) were synthesized. </LI> <LI> The structures were determined by X-ray diffraction. </LI> <LI> The alignment of polarizable Bi<SUP>3+</SUP> cations is critical to second-harmonic generation. </LI> <LI> Photoluminescence measurements exhibit specific emission peaks due to the 4f-4f intrashell transitions of Eu<SUP>3+</SUP> ions. </LI> </UL> </P> <P><B>Graphical abstract</B></P> <P>Second-harmonic generation (SHG) and photoluminescence (PL) properties of NCS bismuth selenite solid solutions, Bi<SUB>2-<I>x</I> </SUB>Ln<SUB> <I>x</I> </SUB>SeO<SUB>5</SUB> (Ln = La and Eu; <I>x</I> = 0–0.3) are presented.</P> <P>[DISPLAY OMISSION]</P>

Current boundary‑based predictive current control of induction machines with lower switching frequencies

Xin Qi,Chenyu Wang,Boxuan Tian,Mario Pacas,Xiangyang Shi,Aibin Jia 전력전자학회 2024 JOURNAL OF POWER ELECTRONICS Vol.24 No.2

An excessively high switching frequency causes significant losses in inverters, especially in high-power applications, which should be avoided. Predictive control, based on a circular boundary restriction strategy presented in this paper, can effectively suppress current distortion while reducing the switching frequency. Until now, this method has been implemented with the same boundaries for both the torque component and flux component of the stator current vector. Due to the physical behavior of an induction motor, a higher current distortion tolerance of the flux component of the stator current vector can be accepted without affecting the torque. Therefore, in this work, the circular boundary restriction strategy is modified to configure larger boundaries for the flux component than for the torque component. This is done to achieve an even lower switching frequency. Furthermore, an additional improvement can be expected if only the boundaries of the torque component are strictly maintained, while the magnetizing current can exceed its boundary to some extent. The predictive control method based on this new strategy is experimentally tested to determine its feasibility. A method based on the circular boundary strategy is also implemented under the same testing conditions, and the performances of both strategies are compared.

Savory Cracker Development for Blood Glucose Control and Management: Glycogen Storage Diseases

Xin Qi,Minh N. Ta,Richard F. Tester 한국식품영양과학회 2024 Journal of medicinal food Vol.27 No.1

The blood glucose response of savory slow energy-release crackers (GLY-HYP) were evaluated in volunteerscarrying glycogen storage diseases (GSDs), Types I (Ia) and IV. The crackers have been shown previously to provide a ‘‘flat’’slow glucose response in healthy volunteers, for up to 4 h. On average for the mixed-sex volunteer group aged 53 to 70 forType I, the blood glucose concentration increased from baseline to a maximum of 9.5 mmol/L at 60 min and remained abovebaseline for up to 210 min; overall, above 5 mmol/L for 4 h. In common with healthy individuals, a relatively flat bloodglucose response was recorded. For Type IV, mixed-sex patients aged between 55 and 72, the blood glucose concentrationreached maximum of 10.2 mmol/L at 45 min and then stayed above baseline for 150 min. Again, overall, above 5 mmol/L for4 h. Altogether, these data indicate that these crackers would provide a valuable contribution to the nutritional needs of peopleof different age groups with GSDs (Clinical Registration Number: HRC10032021).