Enhanced crystallization and properties of poly(ethylene terephthalate) nanocomposites with zeolites from 3D to 2D topologies

Wei Zhang,Hongbin Zhang,Liping Yang,Yi Tang,Ping Tang 한국공업화학회 2022 Journal of Industrial and Engineering Chemistry Vol.109 No.-

To improve the low crystallization rate and long molding cycle of Poly(ethylene terephthalate) (PET), series of PET nanocomposites incorporated small quantities of zeolites with different topologies were blended by melt compounding. The nucleation influence of 3-dimensional zeolites Y, ZSM-5 and 2- dimensional zeolite MCM-22P on the crystallization manner of PET was analyzed by non-isothermal and isothermal crystallization, quantitative evaluation of nanoparticle dispersion and morphology of nanoparticles. The results show that all PET/zeolite nanocomposites exhibit higher crystallization temperature and faster crystallization rate than PET due to large specific surface area of zeolites and their superior dispersion in the PET matrix. Among them, PET/MCM-22P nanocomposites remarkably improved the crystallization behavior, thermal stability and oxygen barrier properties, which is related to the layered morphology of MCM-22P and hydrogen bond interactions between MCM-22P and PET. It is revealed that MCM-22P can provide more heterogeneous nucleation sites for PET by exfoliation in melting compounding. Furthermore, the nucleation mechanism induced by MCM-22P was investigated by the means of Mozhishen method, Avrami equation and theory of Hoffman-Lauritzen. The results indicate that the incorporation of MCM-22P can decrease the free energy of nucleation and fold surface in PET crystallization process, thus improving the crystallinity.

Surface-functionalized Hexagonal Mesoporous Silica Supported 5-(4-Carboxyphenyl)-10,15,20-triphenyl Porphyrin Manganese(III) Chloride and Their Catalytic Activity

Wei-jie Zhang,Pingping Jiang,Ping-bo Zhang,Jia-wei Zheng,Haiyang Li 대한화학회 2012 Bulletin of the Korean Chemical Society Vol.33 No.12

Manganese(III) 5-(4-carboxyphenyl)-10,15,20-triphenyl porphyrin chloride (Mn(TCPP)Cl) was grafted through amide bond on silica zeolite Y (HY), zeolite beta (Hβ) and hexagonal mesoporous silica (HMS). XRD, ICP-AES, N2 physisorption, SEM, TEM, FTIR and thermal analysis were employed to analyse these novel heterogeneous materials. These silica supported catalysts were shown to be used for epoxidation and good shape selectivity was observed. The effect of support structure on catalytic performance was also discussed. The catalytic activity remained when the catalysts were recycled five times. The energy changes about epoxidation of alkenes by NaIO4 and H2O2 were also computationally calculated to explain the different catalytic efficiency.

Analysis on Postoperative Efficacy of Radical Hepatectomy for Patients with Non-HBV/HCV Hepatocellular Carcinoma

Zhang, Zhi-Ming,Zhang, Yu-Mei,Yao, Feng,Yi, Ping,Huang, Shang,Liu, Jian-Yong,Xiang, Bang-De,Yuan, Wei-Ping,Li, Le-Qun Asian Pacific Journal of Cancer Prevention 2015 Asian Pacific journal of cancer prevention Vol.16 No.8

Objective: Patients with hepatocellular carcinoma (HCC) in stage Barcelona Clinic Liver Cancer (BCLC)-A were grouped based on whether they were accompanied with hepatitis B virus (HBV) infection or not so as to explore the clinical characteristics and prognostic conditions of HCC patients with non-HBV/hepatitis C virus (HCV). Materials and Methods: Clinical data of 64 stage BCLC-A HCC patients with non-HBV/HCV infection (observation group) who received radical hepatectomy in the Affiliated Cancer Hospital of Guangxi Medical University from January, 2006 to November, 2014 were retrospectively analyzed and compared with those of 409 stage BCLC-A HCC patients with HBV infection (control group) in corresponding period. Results: The postoperative 1-, 3- and 5-year recurrent rates of the observation group were 25%, 38.6% and 48.8%, with postoperative mean and median disease-free survival time being 49.1 months and 62.0 months, respectively. Additionally, the postoperative 1-, 3- and 5-year survival rates of observation group were 90.1%, 72.7% and 62.0%, with the mean and median survival times being 54.4 months and 70.0 months, respectively. Conclusions: The 1-year recurrent rate is the highest in HCC patients with non-HBV/HCV, and almost half of the patients have recurrence within 1 year, after which the recurrent rate decreases along with the time.

Surface-functionalized Hexagonal Mesoporous Silica Supported 5-(4-Carboxyphenyl)-10,15,20-triphenyl Porphyrin Manganese(III) Chloride and Their Catalytic Activity

Zhang, Wei-Jie,Jiang, Ping-Ping,Zhang, Ping-Bo,Zheng, Jia-Wei,Li, Haiyang Korean Chemical Society 2012 Bulletin of the Korean Chemical Society Vol.33 No.12

Manganese(III) 5-(4-carboxyphenyl)-10,15,20-triphenyl porphyrin chloride (Mn(TCPP)Cl) was grafted through amide bond on silica zeolite Y (HY), zeolite beta ($H{\beta}$) and hexagonal mesoporous silica (HMS). XRD, ICP-AES, $N_2$ physisorption, SEM, TEM, FTIR and thermal analysis were employed to analyse these novel heterogeneous materials. These silica supported catalysts were shown to be used for epoxidation and good shape selectivity was observed. The effect of support structure on catalytic performance was also discussed. The catalytic activity remained when the catalysts were recycled five times. The energy changes about epoxidation of alkenes by $NaIO_4$ and $H_2O_2$ were also computationally calculated to explain the different catalytic efficiency.

Structural instantaneous frequency extraction based on improved multi-synchrosqueezing generalized S-transform

Ping-Ping Yuan,Xue-Li Cheng,Hang-Hang Wang,Jian Zhang,Zhong-Xiang Shen,Wei-Xin Ren 국제구조공학회 2021 Smart Structures and Systems, An International Jou Vol.28 No.5

A new method is proposed to improve the accuracy of structural instantaneous frequency (IF) extraction. The proposed method combines a new form of improved generalized S-transform (IGST) and a multi-synchrosqueezing operation. The parameters selection of the window function in IGST is derived through the concentration measure (CM) principle. Then, the multi-synchrosqueezing algorithm is employed to improve energy aggregation of time-frequency analysis (TFA). To verify the effectiveness and accuracy of the proposed improved multi-synchrosqueezing generalized S-transform (IMSSGST), a frequency-modulated multi-component signal is investigated. For structural IF extraction, a two-story shear frame and a threestory steel frame structure are introduced. Furthermore, the IF identification of a seven-story RC shear wall structure is conducted to verified the practicability in actual engineering. Numerical simulation and experimental results show that the proposed method can effectively improve the energy aggregation of TFA and effectively improve the accuracy of IF identification.

Comparative Study of Field-Oriented Control in Different Coordinate Systems for DTP-PMSM

Zhang, Ping,Zhang, Wei,Shen, Xiaofeng Journal of International Conference on Electrical 2013 Journal of international Conference on Electrical Vol.2 No.3

This paper performs two kinds of Field-Oriented Control (FOC) for dual three phase permanent magnet synchronous motor (DTP-PMSM).The first is based on vector space decomposition to study the effect of current harmonics on electromechanical energy conversion. And the second presents the coupling relations between two sets of windings using two d-q transformation. And then this paper has deeply studied the differences between these two strategies, the different effect on the control of harmonic current and the reason for these differences. MATLAB-based Simulation studies of a 3KW DTP-PMSM are carried out to verify the analysis of differences between the two FOC strategies.

Effects of Stellate Ganglion Block on the Peri-operative Vasomotor Cytokine Content and Intrapulmonary Shunt in Patients with Esophagus Cancer

Guo, Wei,Jin, Xiao-Ju,Yu, Jun,Liu, Yang,Zhang, Jian-Ping,Yang, Da-Wei,Zhang, Lei,Guo, Jiang-Rong Asian Pacific Journal of Cancer Prevention 2014 Asian Pacific journal of cancer prevention Vol.15 No.21

Objective: To investigate the effects of stellate ganglion block (SGB) on the peri-operative vasomotor cytokine content and intrapulmonary shunt in patients with esophagus cancer who underwent thoracotomy. Materials and Methods: Forty patients undergoing elective resection of esophageal cancer patients who had I~II American Society of Anesthesiologist (ASA) were randomly divided into total intravenous anesthesia group (group N, n=20) and total intravenous anesthesia combined with SGB group (group S, n=20, 0.12 mL/kg 1% lidocaine was used for SGB 10 min before induction). Heart rate (HR), mean arterial pressure (MAP), central venous pressure (CVP), mean pulmonary arterial pressure (MPAP) and continuous cardiac output (CCO) were continuously monitored. The blood from internal jugular vein was drawn respectively before induction ($T_0$), and 30 min ($T_1$), 60 min ($T_2$) and 120 min ($T_3$) after one-lung ventilation (OLV), and 30 min (T4) after two-lung ventilation. The contents of plasma endothelin (ET), nitric oxide (NO) and calcitonin gene-related peptide (CGRP) were detected with enzyme linked immunosorbent assay (ELISA). Meanwhile, arterial and mixed venous blood samples were collected for determination of blood gas and calculation of intrapulmonary shunt fraction (Qs/Qt). Results: During OLV, ET contents were increased significantly in two groups (P<0.05), and no significant difference was presented (P>0.05). NO content in group S was obviously higher than in group N at T3 (P<0.05), whereas CGRP content in group N was markedly lower than in group S at each time point (P<0.05). Qs/Qt was significantly increased in both groups after OLV, but there was no statistical significant regarding the Qs/Qt at each time point between two groups. Conclusions: Total intravenous anesthesia combined with SGB is conducive to regulation of perioperative vasomotor cytokines in thoracotomy, and has little effect on intrapulmonary shunt at the time of OLV.

A novel red-emitting phosphor Ca9Bi(PO4)7:Eu3+ for near ultraviolet white light-emitting diodes

Zhi-wei Zhang,Lu Liu,Shi-tao Song,Jian-ping Zhang,Dongjun Wang 한국물리학회 2015 Current Applied Physics Vol.15 No.3

Red phosphors Ca9Bi1-x(PO4)7:xEu3+ (x = 0.06, 0.10, 0.20, 0.30, 0.40, 0.50, 0.60, 0.70, 0.80 and 1.00) were synthesized by a conventional solid-state reaction (SSR) route. The X-ray diffraction patterns, photoluminescence spectra, ultravioletevisible reflection spectroscopy, decay time and the International Commission on Illumination (CIE) chromaticity coordinates of these compounds were characterized and analyzed. The Eu-doped Ca9Bi(PO4)7 phosphors exhibited strong red luminescence which peaks located at 615 nm due to the 5D0/7F2 electric dipole transition of Eu3+ ions after excitation at 393 nm. Ultravioletevisible spectra indicated that the band-gap of Ca9Bi0.30(PO4)7:0.70Eu3+ is larger than that of Ca9Bi(PO4)7. The results indicate that the phosphor Ca9Bi0.30(PO4)7:0.70Eu3+ can be a suitable redemitting phosphor candidate for LEDs.

Carbon dioxide reforming of methane over MgO promoted Ni/CNT catalyst

Dehua Zhang,Guangcheng Wei,Yiru Wang,Jing Wang,Ping Ning,Qiulin Zhang,Mingzhi Wang,Tengfei Zhang,Kaixian Long 한국화학공학회 2018 Korean Journal of Chemical Engineering Vol.35 No.10

Carbon dioxide reforming of methane to syngas was investigated over a series of MgO promoted Ni/CNT catalysts. MgO played a critical role in improving the catalytic performance of Ni/CNT. The results showed that the addition of MgO strengthened the interaction of Ni and interior surface of CNT. Highly dispersed nickel particles with small size (less than 4.5nm) were also observed in MgO modified CNT. Otherwise, the NiO nanoparticles were facilely reduced over the catalyst prepared with a narrow size of CNT, as shown in H2-TPR. The reaction tests demonstrated that the Ni-based catalyst with an addition of MgO and narrow size of CNT exhibited better catalytic activity. Furthermore, the lifetime of Ni-based catalyst was prolonged effectively after adding MgO, attributed to the stabilization and dispersion of Ni particles and the effective restraint on the gasification of CNT.

A New Single-Stage Small Power MH lamp Electronic Ballast

Xiaoqiang Zhang,Wei-ping Zhang,Mao Zhang 한국전기전자재료학회 2016 Transactions on Electrical and Electronic Material Vol.17 No.2

In this study, we proposed a new single-stage small power MH lamp electronic ballast and power-factor correction circuit with improved circuit by the current of passive power factor correction. Main circuit integrates traditional DC/DC and DC/AC circuits into one-stage DC/AC inverter. Moreover, we described the working principle and control strategy of the new circuit; it’s soft switching principle; and resonant element parameter design formula. An experimental prototype of HID lamp electronic ballast with output power of 70 W was built to verify the feasibility of the analysis and design. The simulation and experimental results proved that the power factor of this circuit could reach 94%, with efficiency of 90%. The input current harmonics conform to IEC 61000-3-2 standards and its cost is low. These superior performances of the new circuit indicate certain practical values.