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.

Effects of Endocrine Hormone and Immune System after Exposure to Mixed Cypermethrin and Methylparathion

Ping LIU,Wei-hua WEN,Wei-hong YUAN,Xiao-xiao SONG,Xinan WU 한국환경보건학회 2004 한국환경보건학회 학술대회 자료집 Vol.2004 No.-

THE IMP ACT OF INFORMATION ASYMMETRY ON THE NEW EQUITY ISSUE TIMING

Wei ping Liu 사람과세계경영학회 2000 Global Business and Finance Review Vol.5 No.1

Undervaluation of the firm coupled with the information asymmetry between the issuing firm's management and market investors might be the reasons why new equity issues, on average, are preceded by a large and extended abnormal price rise in the market. If a firm is undervalued (i.e. the intrinsic value of the firm is above its market value) and new equities are needed to finance a new project, the current equity holders would lose a portion of the originally undervalued part after the gap between the market value and the intrinsic. value is eliminated. To avoid this disadvantageous information asymmetry, issuing firm's management is motivated to release inside information to bid up the firm's stock price so that new equity issue will be more beneficial to the issuing firm.

Development of a Small Tea Plucking Machine

( Ping-lang Yen ),( Nai-wen Chang ),( Chen-ya Chen ),( Hong-xuan Wei ),( Shih-fangchen ),( Wei-yang Hwang ) 한국농업기계학회 2018 한국농업기계학회 학술발표논문집 Vol.23 No.1

Tea plucking in Taiwan suffers of serious labor shortage due to agricultural population decreasing and aging. The problems become even worse in hot season of tea plucking and cause tremendous economic loses for farmers. Current solutions of introducing tea harvesting machinery to substitute human power were not adequately suitable to Taiwan's geographical specialty. These machines were found difficult to operate efficiently in mountain areas, or in small tea farms, and farms with narrow ridge to ridge. This paper has proposed a tea plucking prototype that is specially designed to operate in mountain areas and for small scale tea farm. The machine contains a carrier, a tea cutter and a motorized mechanism. The carrier of small size was able to be moved by human and its tea plucking module is motorized. At the same time the height of cutter was automatically adjusted by the controller so that tea leaves can be evenly trimmed during the carrier movement. The prototype successfully demonstrated the efficiency of tea plucking can be increased and workload for human could be significantly reduced. In conclusion, the developed small electrical tea plucking machine was proved feasible for the release of labor shortage problem in Taiwan’s tea plucking industry.

A GENERALIZED DISCOUNTED CASH FLOW MODEL TO COMPUTE STOCK PRICE

Wei ping Liu People&Global Business Association 2005 Global Business and Finance Review Vol.10 No.2

The discounted cash flow method is a commonly-used tool to value security prices. For stock valuation, analysts usually assume companies will pay dividends in a certain pattern. Based on these assumptions, three models were developed to compute stock prices, and they are introduced in most textbooks of financial management. These models, particularly the different growth model, have several limitations. Not only are they cumbersome and error-prone, but they also take too many steps to compute th estock price. These models could be very time-consuming, particularly when the first stage is long. To remedy these problems, a simpler and more general model is developeddebt level when the adjustment requires an increase in debt level according to the target adjustment model.

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.

Three-dimensional Spatiotemporal Accessible Solitons in a PT-symmetric Potential

Wei-Ping Zhong,Milivoj R. Belić,Tingwen Huang 한국광학회 2012 Current Optics and Photonics Vol.16 No.4

Utilizing the three-dimensional Snyder–Mitchell model with a PT-symmetric potential, we study the influence of PT symmetry on beam propagation in strongly nonlocal nonlinear media. The complex Coulomb potential is used as the PT-symmetric potential. A localized spatiotemporal accessible soliton solution of the model is obtained. Specific values of the modulation depth for different soliton parameters are discussed. Our results reveal that in these media the localized solitons can exist in various shapes,such as single-layer and multi-layer disk-shaped structures, as well as vortex-ring and necklace patterns.

Physiological Response of Young Seedlings from Five Accessions of Diospyros L. under Salinity Stress

Wei, Ping,Yang, Yong,Fang, Ming,Wang, Fei,Chen, Hejie Korean Society of Horticultural Science 2016 원예과학기술지 Vol.34 No.4

Salinity stress limits plant cultivation in many areas worldwide; however, persimmon (Diospyros spp.) has high tolerance to salt. Five accessions of Diospyros [three of Diospyros lotus (accession numbers 824, 846, and 847); one of Diospyros kaki var. sylvestris (869); and one of Diospyros virginiana (844)] were chosen for analysis of salinity stress. We compared the effects of salt stress on plant growth, relative water content (RWC), malondialdehyde (MDA), electrolyte leakage (EL), hydrogen peroxide content ($H_2O_2$), and antioxidative enzyme activities (superoxide dismutase, SOD; catalase, CAT; peroxidase, POD; and ascorbate peroxidase, APX) in leaves of healthy potted seedlings from each of the five accessions after salt treatment for 25 days. Salt stress affected the growth of plants in all five accessions, with all three D. lotus accessions showing the most severe effect. Salt stress increased membrane lipid peroxidation in all accessions, but a stronger increase was observed in the three D. lotus accessions. Moreover, accumulation of $H_2O_2$ was faster in salt-sensitive D. lotus compared to salt-tolerant D. virginiana 844. The activities of all antioxidant enzymes increased in D. virginiana 844 and in D. kaki var. sylvestris 869; the activities of SOD, CAT, and APX were at similar levels in D. virginiana 844 and D. kaki var. sylvestris 869, but POD activity was stimulated to a greater extent in D. virginiana 844. The activities of all antioxidant enzymes (except POD) decreased in D. lotus 824 and increased (except for SOD) in D.lotus 846. The activities of SOD and APX decreased in D. lotus 847, whereas POD and CAT activities both increased. Relative water content decreased significantly in D. lotus. No significant changes in lipid peroxidation or relevant antioxidant parameters were detected in any of the accessions in controls treated with 0.0% NaCl. D. virginiana 844 had higher antioxidant capacity in response to salinity compared to other persimmon rootstocks. These results indicate that changes of these key physiological variables are related to salinity resistance in different accessions of persimmon.

Multi-method mercury specification from lignite-fired power plants

Ping Lu,Jiang Wu,Wei-ping Pan 한국화학공학회 2009 Korean Journal of Chemical Engineering Vol.26 No.2

Mercury concentration and speciation partitioning, including total mercury, elemental mercury and oxidized mercury from a lignite-fired power plant under different operating conditions, was studied by Ontario hydro method (OHM), two kinds of continuous mercury monitors (semi-continuous emission monitor (SCEM) and continuous mercury monitor (CMM)), and the sorbent trap method. The effects of boiler load, fuel blending ratio, electrostatic precipitator, flue gas desulphurization, flue gas bypassing the FGD ratio, and mercury measuring methods on mercury emission were analyzed. The results indicated that mercury data from OHM, SCEM and CMM presented a good consistency throughout the entire testing period within ±20% acceptable range; however, the results from Appendix K provided bigger discrepancies than the results of OHM and SCEM due to the interferences of higher selenium content in the flue gas. The particulate-bound mercury removal efficiencies of ESP were determined to be 16-35%. The percentages of elemental mercury emitted from two lignite-fired power plants were in the higher ranges of 43.9-74.2%.

Asymmetric Reduction of Ethyl Acetoacetate Catalyzed by Immobilized Acetobacter sp. CCTCC M209061 Cells in Hydrophilic Ionic Liquid Hybrid System

Ping Wei,Pei Xu,Xiao-Ting Wang,Wen-Yong Lou,Min-Hua Zong 한국생물공학회 2015 Biotechnology and Bioprocess Engineering Vol.20 No.2

The asymmetric reduction of ethyl acetoacetate (EAA) to ethyl (R)-3-hydroxybutyrate [(R)-EHB] using immobilized Acetobacter sp. CCTCC M209061 cells was successfully conducted in a hydrophilic ionic liquid (IL)- containing system. The best one of all the tested watermiscible ILs was 1-(hydroxyethyl)-3-methylimidazolium hydrochloride (C2OHMIM·Cl). In C2OHMIM·Cl-aqueous buffer hybrid system, it was found that the optimal IL concentration, substrate and co-substrate concentration, reaction temperature, buffer pH and shaking rate were 0.5mol/L, 45 mmol/L, 80 mmol/L, 35oC, pH 5.5 and 200 rpm, respectively. Under the optimized reaction conditions, the initial reaction rate, the yield and the product e.e. reached 4.90 μmol/min, 95.3 and > 99.0%, respectively, which were much higher than the corresponding values reported previously. The efficient biocatalytic process mediated by the immobilized cells was feasible on 500 mL preparative scale, and the biocatalysts showed good operational stability and could be recycled for at least 10 batches.