http://chineseinput.net/에서 pinyin(병음)방식으로 중국어를 변환할 수 있습니다.
변환된 중국어를 복사하여 사용하시면 됩니다.
The Design of Anti-aliasing Analog Filter for Data Acquisition in the Surface Measurement
Xu Jingbo,Xu Xiaohong,Yang Pengyu,Lin Haijun,Guo Xin 보안공학연구지원센터 2014 International Journal of Signal Processing, Image Vol.7 No.5
In the surface measurement system, the data acquisition is key part and the anti-aliasing analog filter is necessary. This paper deals with the design of the anti-aliasing analog filter. Based on the principle of anti-aliasing filtering, the parameters of filter are computed, the filter circuit is designed, and the frequency characteristic is drawn. Combined with digital filter, the filtering can maintain the low frequency components very well and suppress effectively the high frequency signals in the original surface profile, which reduces the distortion caused by noise and makes the filtering effect better. This method has been applied in the surface measurement system and the actually measured data verified the performance of the filter.
Chen Haijun,Guo Tengteng,Zhang Lufeng 대한전기학회 2021 Journal of Electrical Engineering & Technology Vol.16 No.4
Five-phase fractional slot concentrated winding permanent magnet (FSCWPM) machine with equal/unequal stator teeth can improve the torque density by added third harmonic current injection (Sin + 3rd). However, the injection of the third harmonic current will change the stator, rotor, and PM losses, and thus the thermal distribution. Therefore, it is necessary to conduct a comparative study on the losses and the thermal performances of the fi ve-phase FSCWPM machine with the sine current supply and Sin + 3rd current supply. In this paper, the structures of the fi ve-phase FSCWPM machines with equal/ unequal stator teeth are illustrated, and their losses characteristic at diff erent rotating speeds including copper loss, PM loss, and iron-core loss are comparatively analyzed under the same output torque constraint. Then, their thermal distributions are investigated based on the coupling of electromagnetic-thermal calculation of the 3D fi nite element (FE) method. The results demonstrate that the fi ve-phase FSCWPM machines energized with the Sin + 3rd current have a better thermal performance at a low rotating speed, especially the fi ve-phase FSCWPM machine with unequal stator teeth. Furthermore, the thermal experiment concerning a fi ve-phase FSCWPM machine with unequal stator teeth is conducted to verify the validity of the related analysis.
Bin, Haijun,Yang, Yankang,Zhang, Zhi-Guo,Ye, Long,Ghasemi, Masoud,Chen, Shanshan,Zhang, Yindong,Zhang, Chunfeng,Sun, Chenkai,Xue, Lingwei,Yang, Changduk,Ade, Harald,Li, Yongfang American Chemical Society 2017 JOURNAL OF THE AMERICAN CHEMICAL SOCIETY - Vol.139 No.14
<P>In the last two years, polymer solar cells (PSCs) developed quickly with n-type organic semiconductor (n-OSs) as acceptor. In contrast, the research progress of nonfullerene organic solar cells (OSCs) with organic small molecule as donor and the n-OS as acceptor lags behind. Here, we synthesized a D-A structured medium bandgap organic small molecule H11 with bithienyl-benzodithiophene (BDTT) as central donor unit and fluorobenzo-triazole as acceptor unit, and achieved a power conversion efficiency (PCE) of 9.73% for the all organic small molecules OSCs with H11 as donor and a low bandgap n-OS IDIC as acceptor. A control molecule H12 without thiophene conjugated side chains on the BDT unit was also synthesized for investigating the effect of the thiophene conjugated side chains on the photovoltaic performance of the p-type organic semiconductors (p-OSs). Compared with H12, the 2D-conjugated H11 with thiophene conjugated side chains shows intense absorption, low-lying HOMO energy level, higher hole mobility and ordered bimodal crystallite packing in the blend films. Moreover, a larger interaction parameter (chi) was observed in the H11 blends calculated from Hansen solubility parameters and differential scanning calorimetry measurements. These special features combined with the complementary absorption of H11 donor and IDIC acceptor resulted in the best PCE of 9.73% for nonfullerene all small molecule OSCs up to date. Our results indicate that fluorobenzotriazole based 2D conjugated p-OSs are promising medium bandgap donors in the nonfullerene OSCs.</P>
Feng Guo,Haijun Zhong,Jing He, Baogang Xie,Fen Liu, Helin Xu,Minmin Liu,Chunlian Xu 대한약학회 2011 Archives of Pharmacal Research Vol.34 No.7
Dipyridamole shows poor and variable bioavailability after oral administration due to pHdependent solubility, low biomembrane permeability as well as being a substrate of P-glycoprotein. In order to improve the oral absorption of dipyridamole, a self-microemulsifying drug delivery system (SMEDDS) for dipyridamole was prepared and evaluated in vitro and in vivo. The optimum formulation was 18% oleic acid, 12% Labrafac lipophile WL 1349, 42% Solutol HS 15 and 28% isopropyl alcohol. It was found that the performance of self-microemulsification with the combination of oleic acid and Labrafac lipophile WL 1349 increased compared with just one oil. The results obtained from an in vitro dissolution assay indicated that dipyridamole in SMEDDS dissolved rapidly and completely in pH 6.8 aqueous media, while the commercial drug tablet was less soluble. An oral bioavailability study in rats showed that dipyridamole in the SMEDDS formulation had a 2.06-fold increased absorption compared with the simple drug suspension. It was evident that SMEDDS may be an effective approach to improve the oral absorption for drugs having pH-dependent solubility.
Piperazine-activated diethanolamine formulation for post-combustion CO2 capture
Bisweswar Das,Haijun Guo,Lian Xiong,Bishnupada Mandal,Arindam Modak,Kamal Kishore Pant,Xinde Chen 한국공업화학회 2023 Journal of Industrial and Engineering Chemistry Vol.118 No.-
Although activated alkanolamine based solvents had great potential for energy-efficient post-combustionCO2 capture, yet these suffers from disadvantageous due to high capital cost of the process. In thisresearch we developed and discussed the overall reaction scheme between CO2 and activated solvents. We investigated the kinetics of CO2 into piperazine (PZ) activated aqueous diethanolamine (DEA) bywetted-wall column contactor at (298–323) K, (5–15) kPa and fixed 3.0 kmol∙m3. Physicochemical propertiesof such systems were determined while detailed uncertainty analysis were conducted. In thermodynamicspoint of view, liquid–liquid interaction were explored and evaluated by related parameters. The kinetics rate parameters for such activated solvents were interpreted based on kinetic study affordingto the pseudo-first-order reaction method. At various temperature, kov of (PZ + DEA + H2O) were considerablylarger than reported (AMP + PZ + H2O) systems. The results of kinetics study demonstrated thatrate of CO2 in solvents were enhanced substantially as compared to DEA due to the addition of low quantity(0–0.45 kmol∙m3) PZ into solvents. Besides, physicochemical properties were measured in terms ofdifferent models with absolute average deviation (AAD) < 5 %. Ultimately, (PZ + DEA + H2O) may be consideredas vital solvents in amine scrubbing due to lower energy requirement for CO2 capture comparedto (PZ + MEA + H2O).
Lijun Yang,Haijun Guo,Kaiting Huang 대한전기학회 2019 Journal of Electrical Engineering & Technology Vol.14 No.2
Because buildings have certain heat capacity, when the thermal power changes, the indoor temperature has a relative lag of change, while the feeling to comfortable temperature of the human body lies within a certain range. Based on the energy storage characteristics of buildings, this paper structures the optimal dispatch model of a combined cooling, heating, and power system (CCHP) and the virtual energy storage system (VESS) is integrated into the model of optimizing schedule on microgrid. This will achieve the charge and discharge management of microgrid virtual energy storage system, with the optimization objectives of minimizing the economic, environmental and energy indexes through determining the weight coeffi cient of each index by analytic hierarchy process (AHP) and through the adjustment of the indoor temperature of the building within the range of human comfort. Finally, taking the summer refrigeration scenario as an example and comparing two microgrids of two types of buildings with or without virtual energy storage, this paper concludes that compared with traditional optimization dispatching methods, the combined cooling, heating, and power optimization dispatching method adopting virtual energy storage fully excavates the potential of the buildings’ virtual storage and every aspect has been improved in terms of economy, environment and energy.
Yang, Yankang,Zhang, Zhi-Guo,Bin, Haijun,Chen, Shanshan,Gao, Liang,Xue, Lingwei,Yang, Changduk,Li, Yongfang American Chemical Society 2016 JOURNAL OF THE AMERICAN CHEMICAL SOCIETY - Vol.138 No.45
<P>Low bandgap n-type organic semiconductor (n-OS) ITIC has attracted great attention for the application as an acceptor with medium bandgap p-type conjugated polymer as donor in nonfullerene polymer solar cells (PSCs) because of its attractive photovoltaic performance. Here we report a modification on the molecular structure of ITIC by side-chain isomerization with meta-alkylphenyl substitution, m-ITIC, to further improve its photovoltaic performance. In a comparison with its isomeric counterpart ITIC with para-alkyl-phenyl substitution, m-ITIC shows a higher film absorption coefficient, a larger crystalline coherence, and higher electron mobility. These inherent advantages of m-ITIC resulted in a higher power conversion efficiency (PCE) of 11.77% for the nonfullerene PSCs with m-ITIC as acceptor and a medium bandgap polymer J61 as donor, which is significantly improved over that (10.57%) of the corresponding devices with ITIC as acceptor. To the best of our knowledge, the PCE of 11.77% is one of the highest values reported in the literature to date for nonfullerene PSCs. More importantly, the m-ITIC-based device shows less thickness-dependent photovoltaic behavior than ITIC-based devices in the active-layer thickness range of 80-360 nm, which is beneficial for large area device fabrication. These results indicate that m-ITIC is a promising low bandgap n-OS for the application as an acceptor in PSCs, and the side-chain isomerization could be an easy and convenient way to further improve the photovoltaic performance of the donor and acceptor materials for high efficiency PSCs.</P>
Zhou, Liben,Cheng, Weizhong,Wang, Deng,Li, Zhaolei,Zhou, Haijun,Guo, Weijie The Korean Electrochemical Society 2022 Journal of electrochemical science and technology Vol.13 No.1
The synergistic effect of 2-chloromethylbenzimidazole (2-CBI) and potassium iodide (KI) for mild steel in 1 M hydrochloric acid solution was investigated by potentiodynamic polarization curves and electrochemical impedance spectroscopy (EIS). The results showed that, with the addition of 100 ppm potassium iodide, the inhibition efficiecy (IE) of 100 ppm 2-CBI in 1 M hydrochloric acid had been improved from 91.14% to 96.15%. And synergistic parameter of 100 ppm 2-CBI with different amounts of potassium iodide is always greater than 1. The adsorption of potassium iodide combining with 100 ppm 2-CBI obeys to the Langmuir adsorption isotherm. Thermodynamic adsorption parameters, including ∆G<sup>0</sup><sub>ads</sub>, ∆H<sub>a</sub> and ∆S<sub>a</sub> of the adsorption of the combinned inhibitor, as well as the E<sub>a</sub> of the mild steel corrosion in 1 M HCl with the combinned inhibitor, were calculated.