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The effect of altering crosslinker chemistry during interfacial polymerization on the performance of nanofiltration membranes for desalination, organic, and micropollutants removal

《化学科学与工程前沿(英文)》 2023年 第17卷 第12期   页码 2025-2036 doi: 10.1007/s11705-023-2356-2

摘要: Chemistry of the polyamide active layer of a desalination membrane is critical in determining both its physical and chemical properties. In this study, we designed and fabricated three novel membranes with different active layers using the crosslinkers: terephthaloyl chloride, isophthaloyl chloride, and trimesoyl chloride. The crosslinkers were reacted with an aqueous solution of an aliphatic tetra-amine. Because these crosslinkers differ in their structures and crosslinking mechanisms during interfacial polymerization, the resultant membranes also possess different structural properties. The water contact angle of the fabricated membranes also varies; the water contact angles of 4A-3P-TPC@PSF/PET, 4A-3P-TMC@PSF/PET, and 4A-3P-IPC@PSF/PET, are 68.9°, 65.6°, and 53.9°, respectively. Similarly, the desalination performance of resultant membranes also showed variations, with 4A-3P-TPC@PSF/PET, 4A-3P-IPC@PSF/PET, and 4A-3P-TMC@PSF/PET having a permeate flux of 17.14, 25.70, and 30.90 L·m−2·h−1, respectively, at 2.5 MPa. The 4A-3P-TPC@PSF/PET membrane exhibited extensive crosslinking with aliphatic linear amine, and cationic dye rhodamine B, MgCl2, and amitriptyline rejection rates of 98.6%, 92.7% and 80.9%, respectively. The 4A-3P-TMC@PSF/PET membrane showed mediocre performance, while 4A-3P-IPC@PSF/PET membrane showed even lower performance, with a 35% rejection of methyl orange dye.

关键词: acid chlorides     covalent crosslinking     desalination     linear aliphatic amine     micropollutant removal     thin film composite membranes    

Reaction and characterization of crosslinking hyperbranched poly (amine-ester) with succine anhydride

XIAO Ling, WEI Xiuzhen, ZHU Baoku

《化学科学与工程前沿(英文)》 2007年 第1卷 第4期   页码 355-359 doi: 10.1007/s11705-007-0064-y

摘要: Basing on hydroxyl terminated hyperbranched poly (amine-ester)s (HPAEs), the cross-linking reactions and preparation of ester-crosslinked HPAE films were investigated using succine anhydride (SA) as crosslink reagent. It was proved that the cross-linking reaction between HPAE and SA followed a two-step mechanism. This mechanism provides an efficient route to prepare HPAE/SA cross-linked films, in which, the precursor films were prepared by casting HPAE/SA solution at a lower temperature, and then curing the films at a higher temperature. By varying SA content, the solid HPAE/SA films with different cross-linking degrees were prepared successfully. The highest tensile strength of the cross-linked film could reach 59.60 MPa. With all water contact angle smaller than 74.3°, the crosslinked films demonstrated good hydrophilic properties.

关键词: different cross-linking     amine-ester     temperature     crosslinked     efficient    

Activated carbons and amine-modified materials for carbon dioxide capture –– a review

Zhenhe CHEN, Shubo DENG, Haoran WEI, Bin WANG, Jun HUANG, Gang YU

《环境科学与工程前沿(英文)》 2013年 第7卷 第3期   页码 326-340 doi: 10.1007/s11783-013-0510-7

摘要: Rapidly increasing concentration of CO in the atmosphere has drawn more and more attention in recent years, and adsorption has been considered as an effective technology for CO capture from the anthropogenic sources. In this paper, the attractive adsorbents including activated carbons and amine-modified materials were mainly reviewed and discussed with particular attention on progress in the adsorbent preparation and CO adsorption capacity. Carbon materials can be prepared from different precursors including fossil fuels, biomass and resins using the carbonization-activation or only activation process, and activated carbons prepared by KOH activation with high CO adsorbed amount were reviewed in the preparation, adsorption capacity as well as the relationship between the pore characteristics and CO adsorption. For the amine-modified materials, the physical impregnation and chemical graft of polyethylenimine (PEI) on the different porous materials were introduced in terms of preparation method and adsorption performance as well as their advantages and disadvantages for CO adsorption. In the last section, the issues and prospect of solid adsorbents for CO adsorption were summarized, and it is expected that this review will be helpful for the fundamental studies and industrial applications of activated carbons and amine-modified adsorbents for CO capture.

关键词: adsorption capacity     CO2 capture     activated carbon     amine-impregnated adsorbents    

Fenton process for degradation of selected chlorinated aliphatic hydrocarbons exemplified by trichloroethylene

QIANG Zhimin, BEN Weiwei, HUANG Chin-Pao

《环境科学与工程前沿(英文)》 2008年 第2卷 第4期   页码 397-409 doi: 10.1007/s11783-008-0074-0

摘要: The degradation of selected chlorinated aliphatic hydrocarbons (CAHs) exemplified by trichloroethylene (TCE), 1,1-dichloroethylene (DCE), and chloroform (CF) was investigated with Fenton oxidation process. The results indicate that the degradation rate was primarily affected by the chemical structures of organic contaminants. Hydroxyl radicals (OH) preferred to attack the organic contaminants with an electron-rich structure such as chlorinated alkenes (i.e., TCE and DCE). The dosing mode of Fenton’s reagent, particularly of Fe, significantly affected the degradation efficiency of studied organic compound. A new “time-squared” kinetic model, = exp(-), was developed to express the degradation kinetics of selected CAHs. This model was applicable to TCE and DCE, but inapplicable to CF due to their varied reaction rate constants towards OH. Chloride release was monitored to examine the degree of dechlorination during the oxidation of selected CAHs. TCE was more easily dechlorinated than DCE and CF. Dichloroacetic acid (DCAA) was identified as the major reaction intermediate in the oxidation of TCE, which could be completely removed as the reaction proceeded. No reaction intermediates or byproducts were identified in the oxidation of DCE and CF. Based on the identified intermediate, the reaction mechanism of TCE with Fenton’s reagent was proposed.

关键词: identified     1     1-dichloroethylene     kinetic     Dichloroacetic     Chloride    

Synthesis, insecticidal activities and DFT study of pyrimidin-4-amine derivatives containing the 1,2,4

《化学科学与工程前沿(英文)》 2022年 第16卷 第7期   页码 1090-1100 doi: 10.1007/s11705-021-2091-5

摘要: Twenty six novel pyrimidin-4-amine derivatives containing the 1,2,4-oxadiazole motif were synthesized. Their chemical structures were confirmed by 1H nuclear magnetic resonance (NMR), 13C NMR, and high-resolution mass spectrography. The insecticidal activity results indicated that some of them possessed excellent insecticidal activity (100%) against Mythimna separate, especially for compounds 6d, 6f, 6o, 6w, 6y and 6z. These compounds exhibited no activity against the insects Aphis medicagini and Tetranychus cinnabarinus. The structure- insecticidal activity relationships are discussed. Density functional theory analysis can potentially be used to design more active compounds. These results provide useful insecticide design information for further optimization.

关键词: synthesis     pyrimidin-4-amine derivatives     1     2     4-oxadiazole     insecticidal activity     structure-activity relationship    

Activated carbon-hybridized and amine-modified polyacrylonitrile nanofibers toward ultrahigh and recyclable

Fengli Li, Chuang Chen, Yuda Wang, Wenpeng Li, Guoli Zhou, Haoqin Zhang, Jie Zhang, Jingtao Wang

《化学科学与工程前沿(英文)》 2021年 第15卷 第4期   页码 984-997 doi: 10.1007/s11705-020-2000-3

摘要: Nanofibers with high specific surface area and chemical stability have broad prospects in the applications of adsorption. However, the adsorption capacity is limited by the scarcity of adsorption groups and storage space. Herein, the activated carbon-hybridized and amine-modified nanofibers are prepared by integrating activated carbon (AC) and polyacrylonitrile (PAN) via electrospinning method and the subsequent amination, which could provide additional storage space and adsorption groups for ultrahigh adsorption capability. Thus, the obtained amine-rich porous PAN nanofibers (APAN/AC) readily realized the ultrahigh adsorption capacity for metal ions and dyes in wastewater. Specifically, the adsorption capacity of APAN/AC nanofibers were 284 mg·g for Cr(VI) and 248 mg·g for methyl orange, which were almost 2 and 4 times than that of amine-modified nanofibers (APAN) and carbon-hybridized nanofibers (PAN/AC), respectively. Moreover, the AC inhibited the chain mobility of polymer matrix and thereby endowing APAN/AC nanofibers with excellent recyclability. The adsorption capability retained 80% after nine adsorption-desorption cycles. The adsorption kinetics and corresponding mechanism were further explored. This strategy combines the advantages of polymer nanofibers and AC, opening a new avenue for developing next-generation absorbent materials.

关键词: carbon-hybridized and amine-modified nanofibers     polyacrylonitrile     metal ions and dyes     wastewater     adsorption kinetics    

Synthesis of spherical parallel manipulator for dexterous medical task

Abdelbadia CHAKER, Abdelfattah MLIKA, Med Amine LARIBI, Lotfi ROMDHANE, Sa?d ZEGHLOUL

《机械工程前沿(英文)》 2012年 第7卷 第2期   页码 150-162 doi: 10.1007/s11465-012-0325-4

摘要:

This paper deals with the design and the analysis of a spherical parallel manipulator (SPM) for a haptic minimally invasive surgery application. First the medical task was characterized with the help of a surgeon who performed a suture technique called anastomosis. A Vicon system was used to capture the motion of the surgeon, which yielded the volume swept by the tool during the anastomosis operation. The identified workspace can be represented by a cone with a half vertex angle of 26°. A multi objective optimization procedure based on genetic algorithms was then carried out to find the optimal SPM. Two criteria were considered, i.e., task workspace and mechanism dexterity. The optimized SPM was then analyzed to determine the error on the orientation of the end effector as a function of the manufacturing errors of the different links of the mechanism.

关键词: spherical parallel manipulator (SPM)     anastomosis     haptic     motion capture     optimization     workspace     dexterity     genetic algorithm     manufacturing errors    

Design and analysis of linear oscillating motor for linear pump application-magnetic field, dynamics

Zongxia JIAO,Tianyi WANG,Liang YAN

《机械工程前沿(英文)》 2016年 第11卷 第4期   页码 351-362 doi: 10.1007/s11465-016-0407-9

摘要:

A linear oscillating motor is an electromagnetic actuator that can achieve short-stroke reciprocating movement directly without auxiliary transmission mechanisms. It has been widely used in linear pump applications as the source of power and motion. However, because of the demand of high power density in a linear actuation system, the performance of linear oscillating motors has been the focus of studies and deserves further research for high power density. In this paper, a general framework of linear oscillating motor design and optimization is addressed in detail, including the electromagnetic, dynamics, and thermal aspects. First, the electromagnetic and dynamics characteristics are modeled to reveal the principle for optimization. Then, optimization and analysis on magnetic structure, resonant system, and thermal features are conducted, which provide the foundation for prototype development. Finally, experimental results are provided for validation. As a whole, this process offers complete guidance for high power density linear oscillating motors in linear pump applications.

关键词: linear oscillating motor     linear pump     magnetic field     motor optimization    

Comparison between linear and non-linear forms of pseudo-first-order and pseudo-second-order adsorption

Junxiong LIN , Lan WANG ,

《环境科学与工程前沿(英文)》 2009年 第3卷 第3期   页码 320-324 doi: 10.1007/s11783-009-0030-7

摘要: The best-fit equations of linear and non-linear forms of the two widely used kinetic models, namely pseudo-first-order and pseudo-second-order equations, were compared in this study. The experimental kinetics of methylene blue adsorption on activated carbon was used for this research. Both the correlation coefficient () and the normalized standard deviation Δ(%) were employed as error analysis methods to determine the best-fitting equations. The results show that the non-linear forms of pseudo-first-order and pseudo-second-order models were more suitable than the linear forms for fitting the experimental data. The experimental kinetics may have been distorted by linearization of the linear kinetic equations, and thus, the non-linear forms of kinetic equations should be primarily used to obtain the adsorption parameters. In addition, the Δ(%) method for error analysis may be better to determine the best-fitting model in this case.

关键词: adsorption     pseudo-first order     pseudo-second order     kinetic model     linear method     non-linear method    

General expression for linear and nonlinear time series models

Ren HUANG, Feiyun XU, Ruwen CHEN

《机械工程前沿(英文)》 2009年 第4卷 第1期   页码 15-24 doi: 10.1007/s11465-009-0015-z

摘要: The typical time series models such as ARMA, AR, and MA are founded on the normality and stationarity of a system and expressed by a linear difference equation; therefore, they are strictly limited to the linear system. However, some nonlinear factors are within the practical system; thus, it is difficult to fit the model for real systems with the above models. This paper proposes a general expression for linear and nonlinear auto-regressive time series models (GNAR). With the gradient optimization method and modified AIC information criteria integrated with the prediction error, the parameter estimation and order determination are achieved. The model simulation and experiments show that the GNAR model can accurately approximate to the dynamic characteristics of the most nonlinear models applied in academics and engineering. The modeling and prediction accuracy of the GNAR model is superior to the classical time series models. The proposed GNAR model is flexible and effective.

关键词: linear and nonlinear     autoregressive model     system identification     time series analysis    

Synthesis of a cardanol-amine derivative using an ionic liquid catalyst

Atanu Biswas, Carlucio R. Alves, Maria T. S. Trevisan, Roseane L. E. da Silva, Roselayne F. Furtado, Zengshe Liu, H. N. Cheng

《化学科学与工程前沿(英文)》 2016年 第10卷 第3期   页码 425-431 doi: 10.1007/s11705-016-1581-3

摘要: Cardanol is a biobased raw material derived from cashew nut shell liquid. In order to extend its utility, new derivatives and additional applications are useful. In this work cardanol was first epoxidized, and a novel aniline derivative prepared from it under mild reaction conditions with the help of an ionic liquid catalyst. The reaction chemistry was studied by using nuclear magnetic resonance. The resulting aminohydrin adduct showed antioxidant property and should also be a useful synthon for further reactions. As an example, the aminohydrin was shown to undergo a condensation reaction with formaldehyde to form a prepolymer, which could be further reacted to form thermosetting resins.

关键词: cardanol     epoxidation     aminohydrin     aniline     ionic liquid     aniline-formaldehyde    

New nanostructured sorbents for desulfurization of natural gas

Lifeng WANG, Ralph T. YANG

《化学科学与工程前沿(英文)》 2014年 第8卷 第1期   页码 8-19 doi: 10.1007/s11705-014-1411-4

摘要: Desulfurization of natural gas is achieved commercially by absorption with liquid amine solutions. Adsorption technology could potentially replace the solvent extraction process, particularly for the emerging shale gas wells with production rates that are generally lower than that from the large conventional reservoirs, if a superior adsorbent (sorbent) is developed. In this review, we focus our discussion on three types of sorbents: metal-oxide based sorbents, Cu/Ag-based and other commercial sorbents, and amine-grafted silicas. The advantages and disadvantages of each type are analyzed. Possible approaches for future developments to further improve these sorbents are suggested, particularly for the most promising amine-grafted silicas.

关键词: desulfurization     natural gas desulfurization     hydrogen sulfide sorbent     amine-silica sorbent    

Asymmetric transfer hydrogenation of prochiral ketone catalyzed over Fe-CS/SBA-15 catalyst

XUE Ping, WU Tao

《化学科学与工程前沿(英文)》 2007年 第1卷 第3期   页码 251-255 doi: 10.1007/s11705-007-0045-1

摘要: A heterogeneous chiral catalyst Fe(III)-CS (chitosan) complex/mesoporous molecular sieve SBA-15 (Santa Barbara Amorphous) was prepared. The asymmetric transfer hydrogenations of prochiral acetophenone and 4-methyl-2-pentanone to corresponding chiral alcohols were carried out on Fe-CS/SBA-15 at atmosphere pressure using 2-propanol as hydrogen donor. Effects of Fe content in catalyst, reaction temperature, reaction time and promoter KOH concentration on the conversion of substrates and enantioselectivity were investigated. Fe-CS/SBA-15 with 2.2% mass fraction Fe exhibits considerable enantioselectivity and catalytic activity for the asymmetric transfer hydrogenations of aromatic ketone and aliphatic ketone. Under optimal reaction conditions: KOH concentration 0.03 mol/L, reaction temperature 70ºC and reaction time 4 h, enantiomer excess (ee) of ()-1-phenylethanol and conversion of acetophenone can reach 87.4% and 27.7%, respectively. Under the above KOH concentration and reaction temperature and reaction time of 8 h, the ee of ()-4-methyl-2-pentanol and conversion 4-methyl-2-pentanone amounted to 50.2% and 25.5%, respectively.

关键词: asymmetric transfer     enantioselectivity     Fe-CS/SBA-15     aliphatic     aromatic    

Multiple linear regression, artificial neural network, and fuzzy logic prediction of 28 days compressive

Faezehossadat KHADEMI,Mahmoud AKBARI,Sayed Mohammadmehdi JAMAL,Mehdi NIKOO

《结构与土木工程前沿(英文)》 2017年 第11卷 第1期   页码 90-99 doi: 10.1007/s11709-016-0363-9

摘要: Evaluating the in situ concrete compressive strength by means of cores cut from hardened concrete is acknowledged as the most ordinary method, however, it is very difficult to predict the compressive strength of concrete since it is affected by many factors such as different mix designs, methods of mixing, curing conditions, compaction, etc. In this paper, considering the experimental results, three different models of multiple linear regression model (MLR), artificial neural network (ANN), and adaptive neuro-fuzzy inference system (ANFIS) are established, trained, and tested within the Matlab programming environment for predicting the 28 days compressive strength of concrete with 173 different mix designs. Finally, these three models are compared with each other and resulted in the fact that ANN and ANFIS models enables us to reliably evaluate the compressive strength of concrete with different mix designs, however, multiple linear regression model is not feasible enough in this area because of nonlinear relationship between the concrete mix parameters. Finally, the sensitivity analysis (SA) for two different sets of parameters on the concrete compressive strength prediction are carried out.

关键词: concrete     28 days compressive strength     multiple linear regression     artificial neural network     ANFIS     sensitivity analysis (SA)    

System construction of a four-side primary permanent-magnet linear motor drive mechanical press

Jintao LIANG, Zhengfeng MING, Peida LI

《机械工程前沿(英文)》 2020年 第15卷 第4期   页码 600-609 doi: 10.1007/s11465-020-0597-z

摘要: A primary permanent-magnet linear motor (PPMLM) has a robust secondary structure and high force density and is appropriate for direct-drive mechanical press. The structure of a four-side PPMLM drive press is presented based on our previous research. The entire press control system is constructed to realize various flexible forming processes. The control system scheme is determined in accordance with the mathematical model of PPMLM, and active disturbance rejection control is implemented in the servo controller. Field-circuit coupling simulation is applied to estimate the system’s performance. Then, a press prototype with 6 kN nominal force is fabricated, and the hardware platform of the control system is constructed for experimental study. Punch strokes with 0.06 m displacement are implemented at trapezoidal speeds of 0.1 and 0.2 m/s; the dynamic position tracking errors are less than 0.45 and 0.82 mm, respectively. Afterward, continuous reciprocating strokes are performed, and the positioning errors at the bottom dead center are less than 0.015 mm. Complex pulse trajectories are also achieved. The proposed PPMLM drive press exhibits a fast dynamic response and favorable tracking precision and is suitable for various forming processes.

关键词: mechanical press     direct drive     primary permanent-magnet linear motor (PPMLM)     servo system     active disturbance rejection control (ADRC)     prototype experiment    

标题 作者 时间 类型 操作

The effect of altering crosslinker chemistry during interfacial polymerization on the performance of nanofiltration membranes for desalination, organic, and micropollutants removal

期刊论文

Reaction and characterization of crosslinking hyperbranched poly (amine-ester) with succine anhydride

XIAO Ling, WEI Xiuzhen, ZHU Baoku

期刊论文

Activated carbons and amine-modified materials for carbon dioxide capture –– a review

Zhenhe CHEN, Shubo DENG, Haoran WEI, Bin WANG, Jun HUANG, Gang YU

期刊论文

Fenton process for degradation of selected chlorinated aliphatic hydrocarbons exemplified by trichloroethylene

QIANG Zhimin, BEN Weiwei, HUANG Chin-Pao

期刊论文

Synthesis, insecticidal activities and DFT study of pyrimidin-4-amine derivatives containing the 1,2,4

期刊论文

Activated carbon-hybridized and amine-modified polyacrylonitrile nanofibers toward ultrahigh and recyclable

Fengli Li, Chuang Chen, Yuda Wang, Wenpeng Li, Guoli Zhou, Haoqin Zhang, Jie Zhang, Jingtao Wang

期刊论文

Synthesis of spherical parallel manipulator for dexterous medical task

Abdelbadia CHAKER, Abdelfattah MLIKA, Med Amine LARIBI, Lotfi ROMDHANE, Sa?d ZEGHLOUL

期刊论文

Design and analysis of linear oscillating motor for linear pump application-magnetic field, dynamics

Zongxia JIAO,Tianyi WANG,Liang YAN

期刊论文

Comparison between linear and non-linear forms of pseudo-first-order and pseudo-second-order adsorption

Junxiong LIN , Lan WANG ,

期刊论文

General expression for linear and nonlinear time series models

Ren HUANG, Feiyun XU, Ruwen CHEN

期刊论文

Synthesis of a cardanol-amine derivative using an ionic liquid catalyst

Atanu Biswas, Carlucio R. Alves, Maria T. S. Trevisan, Roseane L. E. da Silva, Roselayne F. Furtado, Zengshe Liu, H. N. Cheng

期刊论文

New nanostructured sorbents for desulfurization of natural gas

Lifeng WANG, Ralph T. YANG

期刊论文

Asymmetric transfer hydrogenation of prochiral ketone catalyzed over Fe-CS/SBA-15 catalyst

XUE Ping, WU Tao

期刊论文

Multiple linear regression, artificial neural network, and fuzzy logic prediction of 28 days compressive

Faezehossadat KHADEMI,Mahmoud AKBARI,Sayed Mohammadmehdi JAMAL,Mehdi NIKOO

期刊论文

System construction of a four-side primary permanent-magnet linear motor drive mechanical press

Jintao LIANG, Zhengfeng MING, Peida LI

期刊论文