Synthesis and Luminescence Properties of Lanthanide Complexes of a Novel Polyaminopolycarboxylate Ligand

Tang, Chang-Quan,Tang, Rui-Ren,Tang, Chun-Hua,Zeng, Zhi-Wen Korean Chemical Society 2010 Bulletin of the Korean Chemical Society Vol.31 No.5

A novel polyaminopolycarboxylate ligand with many coordination sites, N,N,$N^1,N^1,N^2,N^2$-[( 2,4,6-tri(aminomethyl)-pyridine]hexakis(acetic acid) (TPHA), was designed and synthesized and its lanthanide complexes $Na_6Tb_2$(TPHA)$Cl_6{\cdot}14H_2O$, $Na_6Eu_2$(TPHA)$Cl_6{\cdot}8H_2O$, $Na_6Gd_2$(TPHA)$Cl_6{\cdot}11H_2O$ and $Na_6Sm_2$(TPHA)$Cl_6{\cdot}9H_2O$ were successfully prepared. The ligand and the complexes were characterized by elemental analysis, IR, mass, NMR and TG-DTA. The TG-DTA studies indicated that the complexes had a high thermal stability, whose initial decomposition temperature was over $270^{\circ}C$. The luminescence properties of the complexes in solid state were investigated and the results suggested that $Tb^{3+}$ and $Eu^{3+}$ ions could be sensitized efficiently by the ligand, especially the Tb(III) complex displayed a very strong luminescence intensity (> 10000) and only displayed characteristic metal-centered luminescence. Also, the correlative comparison between the structure of ligand and luminescence properties showed how the number of the coordination atoms of ligand can be a prominent factor in the effectiveness of ligand-to-metal energy transfer.

A new Latuspina Monzen oak gallwasp species from Taiwan (Hymenoptera: Cynipidae: Cynipini)

Chang-Ti Tang,Frazer Sinclair,George Melika 한국응용곤충학회 2012 Journal of Asia-Pacific Entomology Vol.15 No.4

A new species of oak gallwasp, Latuspina manmiaoyangae sp. nov., is described in Taiwan. The species induces leaf galls on Quercus variabilis (Fagaceae). Data on the diagnosis, distribution, and biology of the new species are given. This is the second known Latuspina species.

Transient Characteristics and Physical Constraints of Grid-Tied Virtual Synchronous Machines

Chang Yuan,Chang Liu,Dan Yang,Ruibing Zhou,Niang Tang 전력전자학회 2018 JOURNAL OF POWER ELECTRONICS Vol.18 No.4

In modern power systems, distributed generators (DGs) result in high stress on system frequency stability. Apart from the intermittent nature of DGs, most DGs do not contribute inertia or damping to systems. As a result, a new control method referred to as a virtual synchronous machine (VSM) has been proposed, which brought new characteristics to inverters such as synchronous machines (SM). DGs employing an energy storage system (ESS) provide inertia and damping through VSM control. Meanwhile, energy storage presents some physical constraints in the VSM implementation level. In this paper, a VSM mathematical model is built and analyzed. The dynamic responses of the output active power are presented when a step change in the frequency occurs. The influences of the inertia constant, damping factor and operating point on the ESS volume margins are investigated. In addition, physical constraints are proposed based on these analyses. The proposed physical constraints are simulated using PSCAD/EMTDC software and tested through RTDS experiment. Both simulation and RTDS test results verify the analysis.

A newPlagiotrochus Mayr oak gall wasp species from Taiwan (Hymenoptera: Cynipidae: Cynipini)

Chang-Ti Tang,Man-Miao Yang,GrahamN. Stone,James A. Nicholls,George Melika 한국응용곤충학회 2016 Journal of Asia-Pacific Entomology Vol.19 No.2

A new species of oak gall wasp, Plagiotrochus tarokoensis Tang and Melika sp. nov., is described fromTaiwan. The species induces integral leaf galls on Quercus tarokoensis (Fagaceae). Data on the diagnosis, distribution, and biology of the new species are given. This is the second known Plagiotrochus species from the Oriental region and the first one known to associate with the Ilex group of section Cerris oaks within Quercus linnaeus subgenus Quercus.

Comparison of Dynamic Characteristics between Virtual Synchronous Machines Adopting Different Active Power Droop Controls

Chang Yuan,Chang Liu,Xueyin Zhang,Tianyang Zhao,Xiangning Xiao,Niang Tang 전력전자학회 2017 JOURNAL OF POWER ELECTRONICS Vol.17 No.3

In modern power systems, high penetration of distributed generators (DGs) results in high stress on system stability. Apart from the intermittent nature of DGs, most DGs do not contribute inertia or damping to systems. As a result, a new control method named virtual synchronous machine (VSM) was proposed, which brought new characteristics to inverters such as synchronous machines (SMs). In addition, different active power droop controls for VSMs are being proposed in literatures. However, they are quite different in terms of their dynamic characteristics despite of the similar control laws. In this paper, mathematical models of a VSM adopting different active power droop controls are built and analyzed. The dynamic performance of the VSM output active power and virtual rotor angular frequency are presented for different models. The influences of the damping factor and droop coefficient on the VSM dynamic behaviors are also investigated in detail. Finally, the theoretical analysis is verified by simulations and experimental results.

Rotor dynamics analysis and experiment study of the flywheel spin test system

Tang Chang-Liang 대한기계학회 2012 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.26 No.9

The strength study of the flywheel is important to the flywheel energy storage. The motor and bearing are the key challenges for the high-speed flywheel spin test device in vacuum. By using a small stiffness pivot-jewel bearing and a spring squeeze film damper as the lower support of the flywheel, a simple spin system was designed at a low cost and is suitable for longtime operation. The auxiliary support at the top was not removed until the flywheel passed the first critical speed. The flywheel that kept its rigid state in sub-critical state was tested at the high speed without the top support. The dynamic model of the flywheel-bearing-damper was built by means of the Lagrangian equation to calculate critical speeds, mode shapes and modal damping ratios at different speeds. The lower damper’s effects on the modal damping ratios and forced vibration were discussed. The vibrations of the flywheel-bearing-damper system were measured at the different damping coefficients in the experiment. When the lower damper was adjusted to be overdamped, the flywheel ran up to 50000 r/min steadily, and the experimental result was in agreement with the theoretical assumption. The sub-critical rotor dynamics design and pivot-jewel bearing proved to be good solutions to the spin test for the composite flywheel.

A new Andricus Hartig oak gallwasp species from China (Hymenoptera: Cynipidae: Cynipini)

Chang-Ti Tang,Frazer Sinclair,Man-Miao Yang,George Melika 한국응용곤충학회 2012 Journal of Asia-Pacific Entomology Vol.15 No.4

A new species of oak gallwasp, Andricus xishuangbannaus is described from China. The species induces leaf galls on Quercus griffithii (Fagaceae). Diagnosis, distribution, and biology of the new species are included.

Proactive Consultation by a Clinical Pathologist Prevents Diagnostic Delay in Hematological Malignancies

Chang, Chih-Chun,Su, Ming-Jang,Ho, Jung-Li,Sun, Jen-Tang,Tsai, Huang-Wen,Tang, Hui-Fei,Chu, Fang-Yeh Asian Pacific Journal of Cancer Prevention 2016 Asian Pacific journal of cancer prevention Vol.17 No.3

Background: Diagnostic difficulties in hematological malignancies may lead to unacceptably prolonged help-seeking to diagnostic interval as well as increased complications and poor outcomes. Proactive consultation by a clinical pathologist (PCCP) may help clinical diagnosis and therapeutic strategy. Hence, the aim of this investigation was to evaluate the effect of PCCP on the help-seeking to diagnostic interval in hematological cancer cases. Materials and Methods: From January to November, 2015, abnormal results of hematological laboratory testing with added laboratory comment were selectively screened out, and patients with such abnormalities in hematological laboratory testing and accompanied laboratory comment with PCCP were enrolled. Results: A total of 125 aberrant results of hematological laboratory testing were given with accompanied laboratory comments with PCCP and 40.8% (n=51) of these patient-oriented comments had an effect on clinical diagnosis and therapeutic strategy. Twelve of the subjects belonged to newly diagnosed hematological malignancies with the assistance of PCCP, and the help-seeking to diagnostic interval was also shortened from 42 days to 26 days in chronic lymphoid leukemia (CLL), from 83 days to 11 days in multiple myeloma (MM), and from 128 days to 15 days in myelodysplastic syndrome/myeloproliferative neoplasm (MDS/MPN). During the monitoring interval, neither complication events nor deaths were reported in the study group. Conclusions: It was seemingly that PCCP prevented diagnostic delay in hematological malignancies via shortening the help-seeking to diagnostic interval, particularly in CLL, MM and MDS/MPN cases. PCCP can be considered to play an essential role in prompt establishment of diagnosis in hematological malignancies for those who newly present.

Synthesis and Luminescence Properties of Lanthanide Complexes of a Novel Polyaminopolycarboxylate Ligand

Chang-quan Tang,Rui-ren Tang,Chun-hua Tang,Zhi-wen Zeng 대한화학회 2010 Bulletin of the Korean Chemical Society Vol.31 No.5

A novel polyaminopolycarboxylate ligand with many coordination sites, N,N,N1,N1,N2,N2-[( 2,4,6-tri(aminomethyl)-pyridine]hexakis(acetic acid) (TPHA), was designed and synthesized and its lanthanide complexes Na6Tb2(TPHA)Cl6·14H2O, Na6Eu2(TPHA)Cl6·8H2O, Na6Gd2(TPHA)Cl6·11H2O and Na6Sm2(TPHA)Cl6·9H2O were successfully prepared. The ligand and the complexes were characterized by elemental analysis, IR, mass, NMR and TG-DTA. The TG-DTA studies indicated that the complexes had a high thermal stability, whose initial decomposition temperature was over 270 oC. The luminescence properties of the complexes in solid state were investigated and the results suggested that Tb3+ and Eu3+ ions could be sensitized efficiently by the ligand, especially the Tb(III) complex displayed a very strong luminescence intensity (> 10000) and only displayed characteristic metal-centered luminescence. Also, the correlative comparison between the structure of ligand and luminescence properties showed how the number of the coordination atoms of ligand can be a prominent factor in the effectiveness of ligand-to-metal energy transfer.

Simulation of a neutron imaging detector prototype based on SiPM array readout

Tang Mengjiao,Zhang Lianjun,Tang Bin,He Gaokui,Huang Chang,Zhao Jiangbin,Liu Yang 한국원자력학회 2023 Nuclear Engineering and Technology Vol.55 No.9

Neutron imaging technology as a means of non-destructive detection of materials is complementary to X-ray imaging. Silicon photomultiplier (SiPM), a new type of optical readout device, has overcome some shortcomings of traditional photomultiplier tube (PMT), such as high-power consumption, large volume, high price, uneven gain response, and inability to work in strong magnetic fields. Its application in the field of neutron detection will be an irresistible general trend. In this paper, a thermal neutron imaging detector based on 6 LiF/ZnS scintillation screen and SiPM array readout was developed. The design of the detector geometry was optimized by geant4 Monte Carlo simulation software. The optimized detector was evaluated with a step wedge sample. The results show that the detector prototype with a 48 mm 48 mm sensitive area can achieve about 38% detection efficiency and 0.26 mm position resolution when using a 300 mm thick 6 LiF/ZnS scintillation screen and a 2 mm thick Bk7 optical guide coupled with SiPM array, and has good neutron imaging capability. It provides effective data support for developing high-performance imaging detectors applied to the China Spallation Neutron Source (CSNS).