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N-methyl-2-pyrrolidonium-based Br?nsted-lewis acidic ionic liquids as catalysts for the hydrolysis of cellulose

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Science China Chemistry 2016年第5期59卷 564-570页

作者： Zheng Zhao Na li Abdul Waheed Bhutto Ahmed A. Abdeltawab Salem S. Al-Deyab guangqing liu Xiaochun Chen Guangren Yu Beijing Key laboratory of Membrane Science and Technology College of Chemical EngineeringBeijing University of Chemical TechnologyBeijing 100029China Department of Chemical Engineering Mehran University of Engineering and TechnologyJamshoro 76062Pakistan Petrochemicals Research Chair College of ScienceKing Saud UniversityRiyadh 11451Saudi Arabia

We experimentally studied the catalytic performances of a series of Brrnsted-lewis acidic N-methyl-2-pyrrolidonium metal chlorides （[Hnmp]Cl/MClx, where M=Fe, Zn, A1, or Cu） for the hydrolysis of microcrystalline cellulose （MCC） and cotton to produce reducing sugar. A variety of factors, such as temperature, time, ionic liquid （Il） species, Il dosage, and the concentra- tion of the metal chloride were investigated. [Hnmp]Cl/FeCl3 presented the best hydrolysis performance, affording a 98.8% yield of total reducing sugar from MCC （1 h, 100 ℃, 0.1 g MCC, 0.2 g acidic Il, 2.0 g [Bmim]Cl as solvent）, which is better than or comparable to results previously obtained with other -SO3H functionalized acidic Ils. The hydrolysis performances of [Hnmp]Cl/MClx were rationalized using density functional theory calculations, which indicated that interactions between the metal chlorides and the cellulose, including charge-transfer interactions are important in the hydrolysis of cellulose and degra- dation of glucose. This work shows that Bronsted-lewis acidic Ils are potential catalysts for the hydrolysis of cellulose to produce sugar.

关键词： cellulose hydrolysis ionic liquid density functional theory

Rare earth passivation and corrosion resistance of zinc coated NdFeB magnets

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Journal of Rare Earths 2022年第2期40卷 302-308,I0005页

作者： Jing Chen Hongyi Yang guangqing Xu Pengjie Zhang Jun lv Wei Sun Bingshan lidi Jun Huang Dongmei Wang Xia Shu Yucheng Wu School of Materials Science and Engineering.Hefei University of Technology Hefei 230009China China International S&T Cooperation Base for Advanced Energy and Environmental Materials Hefei University of TechnologyHefei 230009China Key laboratory of Advanced Functional Materials and Devices of Anhui Province Anhui Provincial International S&T Cooperation Base for Advanced Energy MaterialsHefei University of TechnologyHefei 230009China BGRIMM Technology Group Co. Ltd.Beijing 102600China National Engineering Research Center for Magnetic Materials Beijing 102600China

Rare earth passivation was conducted on Zn coated NdFeB magnets by chemical reaction to enhance the corrosion resistance ***,micro structures and compositions of different passivated coatings were studied by X-ray diffraction,field emission scanning electron microscopy,and X-ray photoelectron spectroscopy,*** corrosion behavior was evaluated by electrochemical measurement and neutral salt spray *** results show that the rare earth passivation can enhance the corrosion resistance of Zn coated NdFeB *** the concentration of cerium nitrate is 5 g/l,the passivated specimens can achieve the longest NSS time of 360 h,which is 144 h longer than that of the pristine Zn/NdFeB *** passivation layer on the Zn coating surface contributes to the enhancement of the magnets’corrosion resistance.

关键词： Sintered NdFeB magnets Rare earth passivation Zn coating Electroplating Corrosion resistance

A Review of Research on Tropical Air–Sea Interaction, ENSO Dynamics, and ENSO Prediction in China

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Journal of Meteorological Research 2020年第1期34卷 43-62页

作者： Hong-li REN Fei ZHENG Jing-Jia lUO Run WANG Minghong lIU Wenjun ZHANG Tianjun ZHOU guangqing ZHOU laboratory for Climate Studies National Climate CenterChina Meteorological AdministrationBeijing 100081 Institute of Atmospheric Physics Chinese Academy of SciencesBeijing 100029 Nanjing University of Information Science&Technology Nanjing 210044 Chinese Academy of Meteorological Sciences China Meteorological AdministrationBeijing 100081

Remarkable progress has been made in observations,theories,and simulations of the ocean–atmosphere system,laying a solid foundation for the improvement of short-term climate prediction,among which Chinese scientists have made important *** paper reviews Chinese research on tropical air–sea interaction,ENSO dynamics,and ENSO prediction in the past 70 *** of the tropical air–sea interaction mainly focuses on four aspects:characteristics of the tropical Pacific climate system and ENSO;main modes of tropical Indian Ocean SSTs and their interactions with the tropical Pacific;main modes of tropical Atlantic SSTs and inter-basin interactions;and influences of the mid–high-latitude air–sea system on *** of the ENSO dynamics involves seven aspects:fundamental theories of ENSO;diagnosis and simulation of ENSO;the two types of ENSO;mechanisms of ENSO initiation;the interactions between ENSO and other phenomena;external forcings and teleconnections;and climate change and the ENSO *** ENSO prediction part briefly summarizes the dynamical–statistical methods used in ENSO prediction,as well as the operational ENSO prediction systems and their ***,we discuss some of the issues in these areas that are in need of further study.

关键词： tropical air–sea interaction ENSO dynamics prediction

Densification and anticorrosion performances of vacuum evaporated aluminium coatings on NdFeB magnets

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Journal of Rare Earths 2021年第10期39卷 1238-1245,I0003页

作者： Jun Huang Qing liu Zhenyu Yang guangqing Xu Pengjie Zhang Jun lv Wei Sun Bingshan li Dongmei Wang Yucheng Wu School of Materials Science and Engineering Hefei University of TechnologyHefei 230009China China International S&T Cooperation Base for Advanced Energy and Environmental Materials Hefei University of TechnologyHefei 230009China Key laboratory of Advanced Functional Materials and Devices of Anhui Province Anhui Provincial International S&T Cooperation Base for Advanced Energy MaterialsHefei University of TechnologyHefei 230009China BGRIMM Technology Group Co. Ltd.Beijing 102600China National Engineering Research Center for Magnetic Materials Beijing 102600China

Al coated NdFeB magnets obtained by vacuum evaporation technique were densified by high energy ball milling *** surface morphology,metal composition and micro structure of the coatings were characterized by scanning electron microscopy,X-ray diffraction and X-ray photoelectron spectroscopy,*** anticorrosive properties were investigated by potentiodynamic polarization curves and neutral salt spray *** pores in the Al coatings of columnar crystals(Al) induced by the evaporation technique,were apparently filled in the following ball milling process,leading to the densification of Al coatings and the evident improvement of the anticorrosive *** treated with ball milling for 30 min,the sample achieves the best anticorrosive performances with the self-corrosion potential of-0.87 V,self-corrosion current density of 1.65 μA/cm^(2) and the neutral salt spray(NSS) time of 144 h(red rust).The improvement of the anticorro sive performances of vacuum evaporated Al coating mainly lies in the densification effect of the coating,which depends on different loading conditions of ball milling process.

关键词： Sintered NdFeB magnet Al coating Anticorrosive performances Vacuum evaporation Densification Rare earths

Effect of 3D Printing Technology on 3C Product Manufacturing

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World Journal of Engineering and Technology 2020年第4期8卷 712-719页

作者： guangqing Shang Chunhua Sun College of Electronic Information Engineering Suzhou Vocational University Suzhou China Department of Mechanic and Electronic Engineering Suzhou Vocational University Suzhou China

3D printing technology, as one of the most subversive technologies in the 21st century, processes the entity through layer by layer superposition. It breaks through the design constraints and adapts to customized production with high flexibility, which is an important direction of industrial development in the future. 3C product has a very board application market and groups, so it has been widely valued over the world. The advantages of 3D printing technology are very suitable for the characteristics of 3C product, such as diversification, small-volume, personalized. Here, the impact of 3D printing technology on manufacturing industry is firstly discussed;3C product manufacturing system integrated with 3D printing is finally put proposed. The advantages of the proposed system possess shorter manufacturing cycle, supply chain and logistics. It makes easier to realize personalized 3C product, localized manufacturing and reduce cost. The development and wide application of 3D printing technology in 3C product industry will make the manufacture of low-cost small batch or even individual customized products into a general mode towards the trend of “light luxury + light customization”.

关键词： 3D Printing Additive Manufacturing 3C Product Manufacturing System

Effects of bias voltage on coating structures and anticorrosion performances of PA-PVD Al coated NdFeB magnets

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Journal of Rare Earths 2021年第6期39卷 703-711,I0004页

作者： Yujie Cao Pengjie Zhang Wei Sun Weifeng Zhang Hanzhong Wei Jiquan Wang Bingshan li Xiaofei Yi guangqing Xu Yucheng Wu School of Materials Science and Engineering Hefei University of TechnologyHefei 230009China State Key laboratory of Rare Earth Permanent Magnet Materials Earth-Panda Advance Magnetic Material Co.Ltd.Hefei 231500China BGRIMM Magnetic Materials and Technology(Fu Yang)Co. Ltd.Fuyang 236000China BGRIMM Technology Group Co. Ltd.Beijing 102600China

Al coated NdFeB magnets were prepared by plasma-assisted-physical-vapor-deposition(PA-PVD)method fo r enhancing the corro sion *** rphologies and structures were characterized by an Xray diffractometer and a scanning electron *** behaviors of the samples with different bias voltages were studied by electrochemical methods and neutral salt spray test,*** bias voltage during the deposition process was optimized according to the coating structures and corrosion *** density and flatness of Al coating increase with increasing the bias voltage,and at the same time the thickness *** coating density and thickness turn to be stable when bias voltage is 1800 ***,the corrosion behaviors of PA-PVD Al coatings in different media,such as NaOH,HNO_(3) and NaCl solutions,were *** self-corrosion potentials(E_(corr)) of PA-PVD Al coatings almost keep constant in NaOH and HNO_(3) solutions with diffe rent ***,the self-corrosion current densities(J_(corr)) decrease with the increasing concentrations.E_(corr) shifts to negative potential and J_(corr)decreases gradually when increasing the concentration of NaCl *** corrosion mechanisms of Al coatings are discussed based on the corrosion behaviors in different media.

关键词： Physical vapor deposition Plasma assistance Al coating Sintered NdFeB Corrosion behavior Rare earths

Co-pyrolysis of soybean soapstock with iron slag/aluminum scrap,and characterization and analysis of their products

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Chinese Journal of Chemical Engineering 2023年第1期53卷 25-36页

作者： Xueguang li Mengyan Yu Changfa Zhang Xiangtong li guangqing liu Jianjun Dai Chunbao Zhou Yang liu Jie Fu Yingwen Zhang Bang Yao State Key laboratory of Organic-Inorganic Composites College of Chemical EngineeringBeijing Advanced Innovation Center for Soft Matter Science and EngineeringBeijing University of Chemical TechnologyBeijing 100029China

Soybean soapstock(SS) is one of the main solid wastes produced in the refinery of edible oil processing. In this study, the co-pyrolysis of SS with iron slag(IS) and aluminum scrap(AS) was carried out in a tubular furnace. The gas, liquid and solid products were characterized and the char yield decreased with increasing IS/AS ratio. IS and AS can improve the gas yield, and when the ratio of SS/IS was 1:0.25, the total pyrolysis gas and hydrogen contents were significantly increased. The content of oxygen compounds in pyrolysis oil decreased during co-pyrolysis, while AS promoted the content of polycyclic aromatic hydrocarbons in pyrolysis oil. The co-pyrolysis reaction can be divided into four stages, the mass loss rate reaches the maximum at the third stage(390–575 ℃). The molar ratio of H/C was lower for pyrolysis,indicating good stability of pyrolysis char owing to the high degree of carbonization and *** possible co-pyrolysis reaction mechanism was explored.

关键词： Pyrolysis Soybean soapstock Iron slag Aluminum scrap Adsorption Catalyst

Multipole source-configuration of active sound absorption(ASA)in space sound field

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Chinese Journal of Acoustics 1990年第3期9卷 212-220页

作者： lU guangqing(Institute of Acoustics , Academia Sinica )Institute of Machanical Engineering.Xian Jiaotong University

In this paper, the energy formulas of Active Sound Absorption (ASA) in space sound field have been derived from the basic sound wave equation , and ASA including the relevant conditions of multipole secon -dary-source , such as monopole , dipole and tripole , etc., has been discussed . On the basis of the discussion, it has pointed out that dipole secondary-configuration (DAA) is the simplest attenuator. The results of the experiments done in anechoic chamber have shown that DAA has effective performances which just provide the fundation and feasibility of practical use .

关键词： dipole Absorption chamber formulas discussion directional downstream realization absorbed attenuation

On Application of Metal Additive Manufacturing

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World Journal of Engineering and Technology 2021年第1期9卷 194-202页

作者： Chunhua Sun guangqing Shang Department of Mechanical and Electrical Engineering Suzhou Vocational University Suzhou China Department of Electronics Engineering Suzhou Vocational University Suzhou China

Metal additive manufacturing is an important branch of AM, which provides an effective method for the innovative manufacturing of metal parts. Here, flow chart and main techniques of metal additive manufacturing are firstly described according to the used material types. Many application examples of metal additive manufacturing are then listed based on application value. The summary is finally given to point development direction of metal additive manufacturing in the future. Additive manufacturing, which is an effective supplement to traditional methods, will play an important role in intelligent and digital manufacturing.

关键词： Additive Manufacturing 3D Printing Metal Material Rapid Prototyping