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Science China(Physics,Mechanics & Astronomy) 2018年第3期61卷 56-64页

作者： HuiFang Xiao Bin Huang Ge Yao WenBin Kang Sheng Gong Hai Pan Yi Cao Jun Wang Jian Zhang Wei Wang School of Physics Collaborative Innovation Center of Advanced Microstructures and National Laboratory of Solid State Microstructures Nanjing University Nanjing 210093 China Department of Pharmaceutics Jinling Hospital Nanjing University School of Medicine Nanjing 210002 China School of Public Health and Management Hubei University of Medicine Shiyan 442000 China

Understanding the processes of protein adsorption/desorption on nanoparticles' surfaces is important for the development of new nanotechnology involving biomaterials; however, an atomistic resolution picture for these processes and for the simultaneous protein conformational change is missing. Here, we report the adsorption of protein GB1 on a polystyrene nanoparticle surface using atomistic molecular dynamic simulations. Enabled by metadynamics, we explored the relevant phase space and identified three protein states, each involving both the adsorbed and desorbed modes. We also studied the change of the secondary and tertiary structures of GB1 during adsorption and the dominant interactions between the protein and surface in different adsorption stages. The results we obtained from simulation were found to be more adequate and complete than the previous one. We believe the model presented in this paper, in comparison with the previous ones, is a better theoretical model to understand and explain the experimental results.

关键词：蛋白质吸附动态模拟聚苯乙烯原子论表面解吸附作用纳米技术相互作用

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液压油滤过滤性能建模与分析

液压与气动 2013年第12期37卷 112-114页

作者：杨志敏李昆高亚奎中航工业第一飞机设计研究所陕西西安710089

液压油滤的过滤性能对系统污染控制有非常重要的影响,根据系统中颗粒污染物不断侵入、滤除、解吸附的动态平衡过程,推导出油滤污染过滤模型及工程应用中更为精确的ε过滤比,通过算例介绍了模型在实际系统设计中的应用,为系统抗污染设计... 详细信息

液压油滤的过滤性能对系统污染控制有非常重要的影响,根据系统中颗粒污染物不断侵入、滤除、解吸附的动态平衡过程,推导出油滤污染过滤模型及工程应用中更为精确的ε过滤比,通过算例介绍了模型在实际系统设计中的应用,为系统抗污染设计提供了理论依据。

关键词：过滤模型解吸附作用污染控制 ε过滤比

Hierarchical pore structure of activated carbon fabricated by CO_2/microwave for volatile organic compounds adsorption

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Chinese Journal of Chemical Engineering 2018年第1期26卷 81-88页

作者： Wenjuan Qiu Kang Dou Ying Zhou Haifeng Huang Yinfei Chen Hanfeng Lu College of Environment Zhejiang University of Technology College of Chemical Engineering Zhejiang University of Technology

An activated carbon pore-expanding technique was achieved through innovative reactivation by CO_2/microwave.The original and modified activated carbons were characterized by nitrogen adsorption–desorption,scanning electron microscopy,transmission electron microcopy,and Fourier transform infrared spectroscopy.The mesopore volume increased from 0.122 cm^3·g^(-1) to 0.270 cm^3·g^(-1),and a hierarchical pore structure was formed.A gradual decrease in the phenolic hydroxyl and carboxyl groups on the surface of activated carbon enhanced the surface inertia of granular activated carbon(GAC).The toluene desorption rate of the modified sample increased by 8.81% compared with that of the original GAC.Adsorption isotherm fittings revealed that the Langmuir model was applicable for the original and modified activated carbons.The isosteric adsorption heat of toluene on the activated carbon decreased by approximately 50%,which endowed the modified sample with excellent stability in application.The modified samples showed an enhanced desorption performance of toluene,thereby opening a way to extend the cycle life and improve the economic performance of carbon adsorbent in practical engineering applications.

关键词：解吸附作用孔结构有机化合物激活扫描电子显微镜不稳定 CO2 Fourier

A simple strategy to synthesize and characterization of zirconium modified PCs/γ–Al_2O_3

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Chinese Journal of Chemical Engineering 2018年第5期26卷 1209-1212页

作者： Chidchon Sararuk Dan Yang Guoliang Zhang Chunshan Li Suojiang Zhang Key Laboratory of Ionic Liquid Clean Process Institute of Process Engineering Chinese Academy of Sciences Beijing 100190 China University of Chinese Academy of Sciences Beijing 100190 China

Crystalline phase is the key factor for catalyst activity. The zirconium modified PCs/γ-Al_2O_3 samples were prepared through a simple step incipient-wetness impregnation method. The raw materials and samples were characterized by thermogravimetric-differential analysis(TG-DTA), X-ray diffraction(XRD), Fourier transform infrared spectroscopy(FT-IR), temperature-programmed desorption of ammonia and carbon dioxide(NH_3-and CO_2-TPD). The effects of calcination temperature and zirconium content on structure, chemical transformation,and acidity-basicity were investigated. Calcination temperature exhibited the major effect on the crystalline phase of samples. The new phase of Al0.1Zr_(0.9)O_(1.95) was exhibited which was above 650 ℃. In addition, zirconium content was influenced by the acidic and basic properties of the surface. The acidity and basicity of the Zr PCs/γ-Al_2O_3 sample increased with the increasing of zirconium content.

关键词： Al2O3 PCs 修改 Fourier CO2-TPD 锆锻烧温度解吸附作用

Rh_2O_3/monoclinic CePO_4 composite catalysts for N_2O decomposition and CO oxidation

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Chinese Journal of Chemical Engineering 2018年第1期26卷 109-115页

作者： Huan Liu Zhen Ma Shanghai Key Laboratory of Atmospheric Particle Pollution and Prevention Department of Environmental Science and EngineeringFudan University

CePO_4(in particular,monoclinic CePO_4)has been rarely used to make supported catalysts.Herein,monoclinic CePO_4 nanoparticles were prepared by calcining hexagonal CePO_4 nanorods(prepared by precipitation)in air at 900℃.Monoclinic CePO_4 nanowires were prepared by calcining hexagonal CePO_4 nanowires(prepared by hydrothermal synthesis at 150℃)in air at 900℃.Both monoclinic CePO_4 materials were used to support Rh_2O_3 by impregnation using Rh(NO_3)_3 as a precursor(followed by calcination).The catalytic performance of Rh_2O_3/monoclinic CePO_4 composite materials in N_2O decomposition and CO oxidation was investigated.It was found that Rh_2O_3 supported on monoclinic CePO_4 nanowires was much more active than Rh_2O_3 supported on monoclinic CePO_4 nanoparticles.The stability of catalysts as a function of reaction time on stream was studied in both reactions.The influence of co-fed CO_2,O_2,and H_2O on the catalytic activity in N_2O decomposition was also studied.These catalysts were characterized by employing N_2 adsorption–desorption,ICP-OES,XRD,TEM,XPS,H_2-TPR,O_2-TPD,and CO_2-TPD.The correlation between physicochemical properties and catalytic properties was discussed.

关键词： CePO4 合成催化剂 N2O 分解 CO2-TPD 氧化 ICP-OES 解吸附作用

Enhanced electrokinetic remediation of cadmium-contaminated natural clay using organophosphonates in comparison with EDTA

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Chinese Journal of Chemical Engineering 2018年第5期26卷 1152-1159页

作者： Yingying Gu Albert T. Yeung Hongjiang Li Department of Environmental and Safety Engineering China University of Petroleum (East China) Qingdao 266580 China Department of Engineering The University of Hong Kong Pokfulam Road Hong Kong China Qingdao Water Group Co. Ltd. Qingdao 266002 China College of Mining Civil Engineering Taiyuan University of Technology Taiyuan 030024 China

Soil contamination by metals is a worldwide environmental problem. Electrokinetic extraction is a promising technology for in-situ remediation of contaminated soils of low hydraulic permeability. However, the extraction of metals is usually hindered by the high buffer capacity of natural soils. Organophosphonates are strong metal chelates as ethylenediaminetetraacetic acid(EDTA) which has been widely studied in the enhancement of electrokinetic remediation. In this study, batch desorption experiments and bench-scale electrokinetic extraction experiments were carried out to study the effect of two organophosphonates, i.e.,(nitrilotrimethylene)triphosphonate(NTMP) &(ethylenedinitrilo)-tetramethylenephosphonate(EDTMP), on the extraction of cadmium from a natural clay in comparison with EDTA. Results of the batch desorption experiments showed that more than 75% of the sorbed cadmium could be dissolved into solution using 0.1 mol·L^(-1) organophosphonates or EDTA in the wide p H range of 1–11. Results of the electrokinetic extraction experiments showed that the cadmium spiked in the specimen migrated towards the anode with the enhancement of NTMP,EDTMP, and EDTA under a constant voltage gradient of approximately 1.0 V·cm-1. Although cadmium mobilization enhanced by EDTA was more efficient than that by the organophosphonates, accumulation of cadmium was observed in the vicinity of the anode. The average removal efficiencies of cadmium from the soil after approximately 5 days of electrokinetic extraction enhanced by 0.1 mol·L-1 NTMP(22.8%) and EDTMP(22.4%) were higher than that by 0.1 mol·L^(-1) EDTA(15.1%).

关键词： EDTA 土壤污染自然土壤泥土 EDTMP 镉解吸附作用 NTMP

Using MALDI-TOF MS coupled with a high-mass detector to directly analyze intact proteins in thyroid tissues

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Science China Chemistry 2018年第7期61卷 871-878页

作者： Shan-Shan Wang Yun-Jun Wang Jing Zhang Jun Xiang Tuan-Qi Sun Yin-Long Guo State Key Laboratory of Organometallic Chemistry and National Center for Organic Mass Spectrometry in Shanghai Center for Excellence in Molecular Synthesis Shanghai Institute of Organic Chemistry University of Chinese Academy of Sciences Chinese Academy of Sciences Department of Head and Neck Surgery Fudan University Shanghai Cancer Center Department of Oncology Shanghai Medical College Fudan University

Protein analysis is vital for biological and clinical research, but the measurement of unseparated, intact and high-mass proteins is also a challenging task by mass spectrometry-based methods. Here, we present a protocol for rapid and high-throughput analysis of intact proteins in tissue samples using matrix-assisted laser desorption/ionization time-of-flight mass spectrometry(MALDITOF MS) combined with a high-mass detector platform. The method involves tissue specimens that undergo a simple protein extraction before MALDI-MS analysis. Using this method, the high abundance proteins in human thyroid carcinoma and paracarcinoma tissues were successfully investigated, and the mass spectra of the tissues of the 30 illustrated thyroid cancers showed remarkable differences. The peak intensity revealed a significant increase in human albumin in thyroid carcinoma tissues(p<0.05). To validate the feasibility and credibility of this method, label-free proteomics quantitative analysis and Western blotting were used to relatively quantify the proteins in these tissues. Those results demonstrated a nearly 3-fold difference in human albumin levels between thyroid carcinoma and para-carcinoma tissues, which were consistent with the results of our method. The advantages of our method are easy sample handling, remarkable reproducibility and the ability to analyze high-mass proteins without digestion, which make them have the potential to be used in biological research and in clinical practice.

关键词：蛋白质分析甲状腺癌 MALDI-TOF 纸巾 MS proteomics 解吸附作用定量分析

Ethylbenzene disproportionation and p-xylene selectivity enhancement in xylene isomerization using high crystallinity desilicated H-ZSM-5

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Chinese Journal of Chemical Engineering 2018年第1期26卷 116-126页

作者： Marjan Farshadi Cavus Falamaki Chemical Engineering Department Mahshahr CampusAmirkabir University of TechnologyMahshahr 415Iran Chemical Engneering Department Amirkabir University of TechnologyTehran 15875-4413.Iran Petrochemical Center of Excellence Amirkabir University of TechnologyTehran 15875-4413Iran

Desilication accompanied with minimum loss of crystallinity effect of a high alumina ZSM-5 zeolite on the isomerization reaction of ethylbenzene/xylene mixtures has been considered.Desilication was assessed through XRF,XRD,FTIR,TEM,nitrogen adsorption/desorption,NH_3-TPD,^(29)Si and^(27)Al MAS NMR analytical techniques.Desilication was accompanied with the creation of super acid sites.There exists a limit(Si/Al molar ratio of9.67)for keeping high crystallinity and obtaining improved catalytic performance.Desilication promotes ethylbenzene conversion by disproportionation and trans-alkylation reactions while the same reactions are limited for the xylene isomers.The p-xylene approach to equilibrium improves by more than 7% at 400℃ and a WHSV of 2 h^(-1)for the optimum sample with respect to the parent zeolite.At the same conditions,the optimum sample exhibits the maximum ethylbenzene conversion of 89%,i.***.more than 40%w.***.t.of the parent zeolite.However,the xylene yield decreases only 3%.

关键词：二甲苯异构化 H-ZSM-5 异构化反应 NH3-TPD 解吸附作用 FTIR 催化性能氧化铝

n-Decane hydro-conversion over bi-and tri-metallic Al-HMS catalyst in a mini-reactor

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Chinese Journal of Chemical Engineering 2018年第6期26卷 1330-1339页

作者： Mahdi Abdi-Khanghah Mostafa Adelizadeh Zahra Naserzadeh Zhi'en Zhang Department of Chemical Engineering Petroleum University of Technology Ahwaz Ian Department of Environmental Engineering Azad University of Rudehen Tehran Iran Industrial Safety and HSE Department Faculty ofEngineenng Kar Higher Education Institute Qazvin Iran College of Chemistry and Chemical Engineering Chongqing University of Technology Chongqing 400054 China

Bi-metallic(Pt–Sn and Sn–Ni) and tri-metallic(Pt–Sn–Ni) catalysts,supported on Al-containing hexagonal mesoporous silica(Al-HMS)(Si/Al = 20) materials,were synthesized.N_2 adsorption–desorption,X-ray diffraction(XRD),Brunauer–Emmett–Teller(BET) test,and temperature programed desorption(NH3-TPD)were used to characterize physicochemical characteristics and textural properties of the Al-HMS catalysts.Catalytic performances on hydro-cracking of n-decane at different reaction conditions were studied in a microreactor.Comparison between Pt–Sn,Sn–Ni and Pt–Sn–Ni catalyst under different hydro-cracking conditions was made.The experimental results indicate that the proper balance between the acid and metal functions is the key in synthesizing a catalyst with a better performance in hydro-cracking.Tri-metallic catalyst exhibits the best catalytic performance in n-decane hydro-cracking than two bi-metallic catalysts.

关键词：金属性催化剂微型反应堆解吸附作用 NH3-TPD 水疗 X光检查物理化学

Carbon dioxide induced degradation of diethanolamine during absorption and desorption processes

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Chinese Journal of Chemical Engineering 2018年第2期26卷 293-302页

作者： Md.Sakinul Islam Kotaiah Naik Dhanavath Nhol Kao Pradipto K.Bhattacharjee Brahim Si Ali Rozita Yusoff Department of Chemical Engineering School of EngineeringRMIT UniversityMelbourneVIC 3001Australia Department of Chemical Engineering Faculty of EngineeringUniversity of Malaya50603 Kuala LumpurMalaysia

Alkanolamines are widely used in the purification of the sourgas sweetening process. During the sour gas absorption process, CO_2 significantly degrades the amine solvent and creates enormous problems for plant operation. In this work, CO_2 induced degradation of aqueous diethanolamine(DEA) solution was conducted in a 1.25 L jacketed glass reactor that functioned as an absorber and stripper at atmospheric conditions. Pure CO_2 was bubbled through the reactor until the solution became saturated. In this study, the concentrations of DEA used were in the range of concentrations between 2 mol·L^(-1) and 4 mol·L^(-1). In the degradation experiment, six generic cycles were conducted for each run. Each cycle was configured with the absorption and desorption of carbon dioxide at 55 ℃ and 100 ℃, respectively. Samples were collected after a predetermined experimental time and analyzed by ion chromatography(IC) to identify unknown ionic degradation products(DGPs). In the IC analysis, three different columns were used for anion, cation and ion exclusion systems, which are Metrosep A Supp 5150/4.0, Metrosep C Supp 4 150/4.0 and Metrosep Organic Acids, respectively. The major identified DGPs of D01 DEA2 M, D02 DEA3 M, and D03 DEA4 M are nitrite, acetate and ammonium. Phosphate product was found in the degraded amine samples which might be due to the contamination of water or chromatographic system.

关键词：解吸附作用吸收过程二氧化碳排除系统阴离子 CO2 亚硝酸根反应堆