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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    

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Toughening of vinyl ester resins by two-dimensional MXene nanosheets

《化学科学与工程前沿（英文）》   页码 1651-1658 doi: 10.1007/s11705-022-2208-5

摘要： Two-dimensional nanosheets are highly effective tougheners for vinyl ester resins. The toughening effect is related to the high specific surface area and unique two-dimensional planar structure of the nanosheets. In this study, a coupling agent γ-(2,3-epoxypropoxy) propytrimethoxysilane (Kh-560) was used to modify MXene nanosheets (M-MXene) for use in toughening vinyl ester resin. The mechanical properties, including the tensile strength, flexural strength, Young’s modulus and elongation, of neat vinyl ester resin and vinyl ester resin modified with MXene and M-MXene were investigated. The results showed that modification significantly improved the mechanical properties of the vinyl ester resin. The tensile and flexural strengths of the MXene-nanosheet-modified vinyl ester resin were 27.20% and 25.32% higher, respectively, than those of the neat vinyl ester resin. The coupling agent improved the interfacial compatibility between the MXene nanosheets and vinyl ester resin, which resulted in the tensile and flexural strengths of the M-MXene-nanosheet-modified vinyl ester resin being 52.57% and 54.60% higher, respectively, than those of the neat vinyl ester resin for a loading quantity of nanosheets of only 0.04 wt %, which is economically viable. The main mechanisms by which the nanosheets toughen the resin are crack deflection and crack pinning.

关键词： MXene nanosheets     2D material     vinyl ester resin     modification     coupling agent    

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The prediction of adsorption isotherms of ester vapors on hypercrosslinked polymeric adsorbent

Liuyan WU,Lijuan JIA,Xiaohan LIU,Chao LONG

《环境科学与工程前沿（英文）》 2016年 第10卷 第3期   页码 482-490 doi: 10.1007/s11783-015-0826-6

摘要： Adsorption isotherms of methyl acetate, ethyl acetate, propyl acetate, isopropyl acetate and ethyl propionate on hypercrosslinked polymeric resin (ND-100) were measured at 303K, 318K and 333K,respectively, and well fitted by Dubinin–Astakhov (DA) equation. The plots of the adsorbed volume ( ) versus the adsorption potential ( ) at three different temperatures all fell basically onto one single curve for every ester. A predicted model based on DA equation was obtained on the basis of adsorption equilibrium data of methyl acetate, ethyl acetate and ethyl propionate at 318K. The model equation successfully predicted the adsorption isotherms of methyl acetate, ethyl acetate and ethyl propionate on ND-100 at 303K, and 333K, and also gave accurate predictive results for adsorption isotherms of the other two ester compounds (propyl acetate and isopropyl acetate) on ND-100 at 303K, 318K and 333K. The results proved the effectiveness of DA model for predicting the adsorption isotherms of ester compounds onto ND-100. In addition, the relationship between physico-chemical properties of adsorbates and their adsorption properties was also investigated. The results showed that molecular weight, molar volume and molar polarizability had good linear correlations with the parameter (which represents adsorption characteristic energy) of DA equation.

关键词： hypercrosslinked polymeric adsorbent     adsorption isotherm     ester     prediction    

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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    

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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    

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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    

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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    

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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    

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用于锂离子电池的富醚/酯/氟黏结剂配方 Article

Xianqing Zeng, Donglin Han, Zeheng Li, Hongxun Wang, Gu Wu, Yong Deng, Kai Liu, Li Xie, Chengdu Liang, Min Ling, Yuchuan Huang

《工程（英文）》 2022年 第19卷 第12期   页码 199-206 doi: 10.1016/j.eng.2022.05.020

摘要：

由于硅阳极体积膨胀过大，无法在高能量密度电池中实现实际应用。研究人员一直专注于在阳极中添加黏结剂以限制体积膨胀，来解决这一问题，因为黏结剂的氢键和机械性能可以用来增强黏附力和适应硅阳极的体积变化。在这里，我们综合考虑了黏结剂的氢键、力学性能、稳定性以及与电解液的相容性，设计了一种富醚/酯/氟的复合聚合物P(TFEMA-co-IBVE)。该黏结剂配方具有优异的稳定性、黏结性和机械强度，能够适应硅电极体积的剧烈变化，表现出优异的电化学性能，面积容量高达5.4 mA∙h∙cm−2。这种新型聚合物设计可应用于下一代锂离子电池的其他电极材料。

关键词： 硅阳极     乳液共聚合     氟原子     醚     酯    

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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    

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Potential hybrid feedstock for biodiesel production in the tropics

Solomon GIWA,Oludaisi ADEKOMAYA,Collins NWAOKOCHA

《能源前沿（英文）》 2016年 第10卷 第3期   页码 329-336 doi: 10.1007/s11708-016-0408-8

摘要： Recently, mixture of different oils at various proportions have been used as feedstock for biodiesel production. The primary aim is to improve fuel properties which are strongly influenced by the fatty acid composition of the individual oil that makes up the feedstock mix. The tropics are renowned for abundant oil-bearing crops of which palm kernel oil (PKO) from palm seed and groundnut oil (GNO) are prominent. This present paper investigated biodiesel production from hybrid oil (HO) of PKO (medium carbon chain and highly saturated oil) and GNO (long carbon chain and highly unsaturated oil) at 50/50 (v/v) blending. The principal fatty acids (FAs) in the HO are oleic (35.62%) and lauric acids (24.23%) with 47.80% of saturated FA and 52.26% of unsaturated FA contents. The chemical conversion of the oil to methyl ester (ME) gave 86.56% yield. Fuel properties of hybrid oil methyl ester (the HOME) were determined in accordance with standard test methods and were found to comply with both ASTM D6751 and EN 14214 standards. The oxidative stability, cetane number and kinematic viscosity (KV) of HOME were observed to be improved when compared with those of GNO methyl ester from single parent oil, which could be accredited to the improved FA composition of the HO. The KV (3.69 mm /s) of HOME obtained in this paper was remarkably low compared with those reported in literature for most biodiesels. This value suggests better flow, atomization, spray and combustion of this fuel. Conclusively, the binary blend of oils can be a viable option to improve the fuel properties of biodiesel feedstock coupled with reduced cost.

关键词： groundnut oil     palm kernel oil     methyl ester     fuel properties     tropics     fatty acid composition    

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Supercritical carbon dioxide extraction of CLA-ethyl ester

Yingdi CHEN, Peng XU, Jian CHENG

《化学科学与工程前沿（英文）》 2011年 第5卷 第1期   页码 102-106 doi: 10.1007/s11705-010-0536-3

摘要： Supercritical carbon dioxide (SC-CO ) extraction of Conjugated linoleic acid (CLA) ethyl ester was investigated at pressures in the range of 9 to 10.5 MPa and temperature gradients ranging from 0°C to 21°C. The content of CLA-ethyl ester in the fraction was analyzed with gas chromatography (GC). The experimental results indicated that the rate of extraction would rise with the increase of pressure when temperature gradient was given. Moreover, the extraction pressure had insignificant influence on the selectivity of CLA-ethyl ester in SC-CO . When pressure was fixed, setting certain temperature gradient can improve the selectivity of CLA-ethyl ester in SC-CO , and CLA-ethyl ester can be concentrated more effectively than without a temperature gradient. The acid value and peroxide value of the fractions were reduced obviously, compared to the raw material. The optimal condition is pressure at 10 MPa and temperature gradient at 11°C.

关键词： supercritical carbon dioxide     extraction     CLA-ethyl ester     temperature gradient    

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Preparation of adsorptive nanoporous membrane using powder activated carbon: Isotherm and thermodynamic studies

Majid Peyravi

《化学科学与工程前沿（英文）》 2020年 第14卷 第4期   页码 673-687 doi: 10.1007/s11705-019-1800-9

摘要： Adsorptive polyethesulfone (PES) membranes were prepared by intercalation of powder activated carbon (PAC) with and without functionalization. Accordingly, PAC was aminated with 1,5-diamino-2-methylpentane, and the physicochemical properties of the functionalized PAC were analyzed. Intercalation of PAC within the PES scaffold changed the porosity and mean pore size of the aminated membrane (AC-NH ) from 52.6% to 92.5% and from 22.6 nm to 3.5 nm, respectively. The effect of temperature on the performance of the modified membranes was monitored by the flux and chemical oxygen demand (COD) removal of leachate. At ambient temperature, the COD removal of the neat, AC-containing, and AC-NH membranes was 47%, 52%, and 58.5%, respectively. A similar increment was obtained for the membrane flux, which was due to the synergistic effect of the high porosity and large number of hydrophilic functional groups. The experimental leachate adsorption data were analyzed by Langmuir, Freundlich, and Dubinin- Radushkevich isotherm models. For all membranes, the significant thermodynamic parameters ( , , and ) were calculated and compared. The isosteric heat of adsorption was lower than 80 kJ∙mol , indicating that the interaction between the membranes and the leachate is mainly physical, involving weak van der Waals forces.

关键词： amine functionality     nanoporous membrane     adsorption isotherm     thermodynamic parameters     landfill leachate    

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Impact and inhibitory mechanism of phenolic compounds on the formation of toxic Maillard reaction products in food

Jing TENG, Xiaoqian HU, Ningping TAO, Mingfu WANG

《农业科学与工程前沿（英文）》 2018年 第5卷 第3期   页码 321-329 doi: 10.15302/J-FASE-2017182

摘要：

As one of the dominant reactions occurring during thermal treatment of food, the Maillard reaction not only leads to the formation of aroma, browning color and taste compounds, but also contributes to the formation of some unpleasant toxic substances including acrylamide, heterocyclic amines and advanced glycation end products. Polyphenols, one of the most abundant antioxidants in the human diet, are contained in different kinds of foods. In this review, some recent studies on the impact of dietary polyphenols on the formation of acrylamide, heterocyclic amines and advanced glycation end products formed during the Maillard reaction are summarized, including the research work conducted with both chemical model systems and real food model systems; the possible inhibitory mechanisms of different polyphenols are also summarized and discussed in this review. Basically we found that some dietary polyphenols not only scavenge free radicals, but also react with reactive carbonyl species, thus lowering the formation of toxic Maillard reaction products. This review provides a useful theoretical foundation for the application of polyphenols in food safety, and suggests some directions for further study of natural products as inhibitors against the formation of toxic substances in thermally processed food.

关键词： advanced glycation end products     acrylamide     food safety     heterocyclic amine     Maillard reaction     polyphenols    

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口袋改造策略克服ω-氨基转移酶AtATA对1-乙酰基萘活性和稳定性之间的"trade-off"效应 Article

曹佳仁, 樊芳芳, 吕常江, 胡升, 赵伟睿, 梅家祺, 邱帅, 梅乐和, 黄俊

《工程（英文）》 2023年 第30卷 第11期   页码 203-214 doi: 10.1016/j.eng.2023.04.009

摘要：

氨基转移酶是一种能够催化前手性酮或醛不对称胺化生成相应的手性胺的生物催化剂。然而，活性和稳定性之间的“trade-off”效应限制了其在工业生产中的应用。因此，开发克服这种相互抵消的“trade-off”效应的普适方法以及获得高效催化的氨基转移酶具有重要意义。对此，我们针对土曲霉属氨基转移酶（AtATA）的底物结合口袋进行共进化改造，以确定控制AtATA对1-乙酰基萘活性和稳定性的关键氨基酸。通过多轮实验筛选，我们发现了一个含四个关键氨基酸位点（R128，V149，L182和L187）的“结构开关”， “最佳”突变体（AtATA_D224K/V149A/L182F/L187F; 命名为M4）。与亲本酶AtATA_D224K（AtATAPa）相比，M4的催化效率（kcat/Km1-乙酰基萘，其中kcat是催化活性常数，为10.1 min-1，Km1-乙酰基萘是米氏常数，为1.7 mmol·L-1）和半衰期（t1/2）分别增加59倍和1.6倍。此外，在50 mL反应体系中，M4催化20 mmol·L-1 1-乙酰基萘，反应10 h后可获得产率为78%的目标产物(R)-(+)-1-(1-萘基)乙胺（(R)-NEA），对映体纯度达到R > 99.5%。同时，M4还显示出对各种1-乙酰萘酮类似物显著增强的催化活性。通过结构和序列信息分析，进一步发现分子内相互作用的加强以及底物结合口袋和5’-磷酸吡哆醛（PLP）结合口袋之间的角度扩大是AtATA热稳定性和活性同步增强的重要原因。最后，口袋工程策略也将增强的活性和热稳定性成功地转移到其他三个序列相似性介于8%~22%之间的氨基转移酶中。这项研究对于克服ATA活性和热稳定性之间的权衡具有重要意义。

关键词： “trade-off”效应     共进化     氨基转移酶     口袋改造    

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标题 作者 时间 类型 操作

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

XIAO Ling, WEI Xiuzhen, ZHU Baoku

期刊论文

Toughening of vinyl ester resins by two-dimensional MXene nanosheets

期刊论文

The prediction of adsorption isotherms of ester vapors on hypercrosslinked polymeric adsorbent

Liuyan WU,Lijuan JIA,Xiaohan LIU,Chao LONG

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

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

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

用于锂离子电池的富醚/酯/氟黏结剂配方

Xianqing Zeng, Donglin Han, Zeheng Li, Hongxun Wang, Gu Wu, Yong Deng, Kai Liu, Li Xie, Chengdu Liang, Min Ling, Yuchuan Huang

期刊论文

New nanostructured sorbents for desulfurization of natural gas

Lifeng WANG, Ralph T. YANG

期刊论文

Potential hybrid feedstock for biodiesel production in the tropics

Solomon GIWA,Oludaisi ADEKOMAYA,Collins NWAOKOCHA

期刊论文

Supercritical carbon dioxide extraction of CLA-ethyl ester

Yingdi CHEN, Peng XU, Jian CHENG

期刊论文

Preparation of adsorptive nanoporous membrane using powder activated carbon: Isotherm and thermodynamic studies

Majid Peyravi

期刊论文

Impact and inhibitory mechanism of phenolic compounds on the formation of toxic Maillard reaction products in food

Jing TENG, Xiaoqian HU, Ningping TAO, Mingfu WANG

期刊论文

口袋改造策略克服ω-氨基转移酶AtATA对1-乙酰基萘活性和稳定性之间的"trade-off"效应

曹佳仁, 樊芳芳, 吕常江, 胡升, 赵伟睿, 梅家祺, 邱帅, 梅乐和, 黄俊

期刊论文