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Journal of Rare Earths 2016年第7期34卷 667-674页

作者：宋忠贤张秋林宁平刘昕樊洁黄真真 faculty of Environmental science and engineering Kunming University of Science and Technology college of Environmental science and engineering Hunan University

A series of sulfated ceO2 catalysts were synthesized by impregnation and sol-gel methods and used for selective catalytic reduction （ScR） of NOx by NH3. The results showed that the sulfated ceO2 catalysts prepared by sol-gel method showed excellent catalytic activity at 150-50 ℃, and more than 90% NOx conversion was obtained at 232-450 ℃ with a gas hourly space velocity of 60000 h-1. The catalysts were characterized by X-ray diffraction （XRD）, N2 adsorption, Raman, thermogravimetry （TG）, H2-tem- perature-programmed reduction （H2-TPR） and Py-infrared spectroscopy （Py-IR）. The excellent ScR performance was associated with the surface acidity and the micro-structure. The introduction of sulfate acid into ceO2 could increase the amount of BrOnsted and Lewis acid sites over the catalysts, resulting in the improvement of the low temperature activity. The sulfated ceO2 catalysts prepared by sol-gel method possessed lower crystallization degree, excellent redox property and larger specific surface areas, which were responsible for the superior ScR performance.

关键词： sulfated ceO2 selective catalytic reduction surface acidity micro-structure rare earthsO

Activity and hydrothermal stability of ceO_2–ZrO_2–WO_3 for the selective catalytic reduction of NO_x with NH_3

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Journal of Environmental sciences 2016年第4期28卷 168-177页

作者： Zhongxian Song Ping Ning Qiulin Zhang Hao Li Jinhui Zhang Yancai Wang Xin Liu Zhenzhen Huang faculty of Environmental science and engineering Kunming University of Science and Technology college of Environmental science and engineering Hunan University

A series of ceO2–ZrO2–WO3（cZW）catalysts prepared by a hydrothermal synthesis method showed excellent catalytic activity for selective catalytic reduction（ScR）of NO with NH3 over a wide temperature of 150–550℃.The effect of hydrothermal treatment of cZW catalysts on ScR activity was investigated in the presence of 10% *** fresh catalyst showed above 90% NOx conversion at 201–459℃,which is applicable to diesel exhaust NOx purification（200–440℃）.The ScR activity results indicated that hydrothermal aging decreased the ScR activity of cZW at low temperatures（below 300℃）,while the activity was notably enhanced at high temperature（above 450℃）.The aged cZW catalyst（hydrothermal aging at 700℃ for 8 hr）showed almost 80% NOx conversion at 229–550℃,while the V2O5–WO3/TiO2 catalyst presented above 80% NOx conversion at 308–370℃.The effect of structural changes,acidity,and redox properties of cZW on the ScR activity was *** results indicated that the excellent hydrothermal stability of cZW was mainly due to the ceO2–ZrO2 solid solution,amorphous WO3 phase and optimal *** addition,the formation of WO3 clusters increased in size as the hydrothermal aging temperature increased,resulting in the collapse of structure,which could further affect the acidity and redox properties.

关键词： ceO2–ZrO2–WO3 Hydrothermal stability Solid solution Acidity

Quantitative determination of erlotinib in human serum using competitive enzyme-linked immunosorbent assay

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Journal of Pharmaceutical Analysis 2018年第2期8卷 119-123页

作者： Yuta Yamamoto Tetsuya Saita Yutaro Yamamoto Masashi Shin applied Life science Department Faculty of Biotechnology and Life Science Sojo University

A selective and sensitive competitive enzyme-linked immunosorbent assay(ELISA) method was developed and validated for the quantification of erlotinib in 50 mL of samples of human serum. Anti-erlotinib serum was obtained by immunizing mice with an antigen conjugated with bovine serum albumin and 3,4-bis(2-methoxyethoxy)benzoic acid using the N-succinimidyl ester method. Enzyme labeling of erlotinib with horseradish peroxidase was similarly performed using 3,4-bis(2-methoxyethoxy)benzoic acid. A simple competitive ELISA for erlotinib was developed using the principle of direct competition between erlotinib and the enzyme marker for anti-erlotinib antibody, which had been immobilized on the plastic surface of a microtiter plate. Serum erlotinib concentrations lower than 40 ng/mL were reproducibly measurable using the ELISA. This ELISA was specific to erlotinib and showed very slight cross-reactivity(6.7%) with a major metabolite, O-desmethyl erlotinib. Using this assay, drug levels were easily measured in the blood of mice after oral administration of erlotinib at a single dose of 30 mg/kg. ELISA should be used as a valuable tool for therapeutic drug monitoring and in pharmacokinetic studies of erlotinib.

关键词： Erlotinib Enzyme-linked immunosorbent assay O-desmethyl erlotinib Tyrosine-kinase inhibitor

Influence of calcination temperature on selective catalytic reduction of NO_x with NH_3 over ceO_2-ZrO_2-WO_3 catalyst

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Journal of Rare Earths 2015年第7期33卷 726-735页

作者：李军燕宋忠贤宁平张秋林刘昕李昊黄真真 faculty of Environmental science and engineering Kunming University of Science and Technology college of Environmental science and engineering Hunan University

A series of ceO2-ZrO2-WO3 catalysts for the selective catalytic reduction （ScR） of NO with NH3 were prepared by hydrothermal method. The influence of calcination temperature on the catalytic activity, microstructure, surface acidity and redox behavior of ceO2-ZrO2-WO3 catalyst was investigated using various characterization methods. It was found that the ceO2-ZrO2-WO3 catalyst calcined at 600 ℃ showed the best catalytic performance and excellent N2 selectivity, and yielded more than 90% NO conversion in a wide temperature range of 250-500 ℃ with a space velocity （GHSV） of 60000 131. As the calcination temperature was increased from 400 to 600 ℃, the NO conversion obviously increased, but decreased at higher calcination temperature. The results implied that the higher surface area, the strongest synergistic interaction, the superior redox property and the highly dispersed or amorphous WO3 species contributed to the excellent ScR activity of the ceO2-ZrO2-WO3 catalyst calcined at 600℃.

关键词： ceO2-ZrO2-WO3 selective catalytic reduction calcination temperature amorphous synergistic interaction rare earths

In situ backscattered electron imaging study of the effect of annealing on the deformation behaviors of Ni electroformed from additive-free and saccharin-containing sulfamate solutions

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International Journal of Minerals,Metallurgy and Materials 2019年第1期26卷 114-123页

作者： Kai Jiang Hiroaki Nakano Satoshi Oue Tatsuya Morikawa Wen-huai Tian School of Materials science and engineering University of Science and Technology Beijing faculty of engineering Kyushu University

The Ni samples were electroformed from additive-free(AF) and saccharin-containing(Sc) sulfamate solutions, respectively. In situ backscattered electron(BSE) imaging, electron backscatter diffraction(EBSD), and electron-probe microanalysis(EPMA) were used to investigate the effect of annealing on the deformation behaviors of the AF and Sc samples. The results indicate that columnar grains of the as-deposited AF sample had an approximated average width of 3 μm and an approximated aspect ratio of 8. The average width of columnar grains of the as-deposited Sc sample was reduced to approximately 400 nm by the addition of saccharin to the electrolyte. A few very-large grains distributed in the matrix of the Sc sample after annealing. No direct evidence indicated that S segregated at the grain boundaries before or after annealing. The average value of the total elongations of the Sc samples decreased from 16% to 6% after annealing, whereas that of the AF samples increased from 18% to 50%. The dislocation recovery in grain-boundary areas of the annealed AF sample was reduced, which contributed to the appearance of microvoids at the triple junctions. The incompatibility deformation between very-large grains and fine grains contributed to the brittle fracture behavior of the annealed Sc Ni.

关键词： backscattered electron imaging annealing electroformed Ni sulfamate solution deformation behaviors

Mapping the structure-activity relationship of β-sitosteryl fatty acid esters in condensing phospholipid monolayers

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Frontiers of chemical science and engineering 2015年第1期9卷 105-113页

作者： Worawan PANPIPAT Hasene KESKIN Zheng GUO Department of engineering Faculty of Science Aarhus University Gustav Wieds Vej 10 8000 Aarhus C Denmark Department of Food engineering Faculty of Engineering University of Gaziantep 27310 Gaziantep Turkey

Abstract The phase behavior of twelve synthesized β- sitosteryl fatty acid esters with acyl moieties with different chain lengths （c2：0-c18：0） and different degrees of unsaturation （c18：1-c18：3） were investigated in pure and mixed Langmuir monolayers with phospholipids. The surface-pressure isotherms showed that short chain fl- sitosteryl fatty acid esters gave smaller mean molecular areas and had decreased monolayer stability and the long chain steryl esters did not produce collapsed plateaus. All the steryl esters displayed strong condensing effects, but there was a pronounced structural dependency： medium chain esters （c8 and c 10） were less efficient than short and long chain esters. Atomic force microscopy imaging demonstrated that monolayers mixed with dipalmitoyl phosphatidylcholine （DPPc） displayed both DPPc-rich and steryl lipid-rich domains. However, the height and area differences between the two phases and the roughness and morphologic patterns were very dependent on the steryl lipid concentrations as well as the length, the degree of unsaturation and the molecular conformations of the acyl segments. These findings not only provide a better understanding of the interactions between phytosteryl hydrophobic derivatives and biomembranes, but also may be of general use for the design and engineering of phytosterol structural derivations for specific food and pharmaceutical applications.

关键词： β-sitosteryl fatty acid esters dipalmitoylphosphatidylcholine Langmuir monolayer condensingeffect structure-activi .ty relationship

The influence of hydrogel soil amendment on the survival and growth of newly transplanted Pinus patula seedlings

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Journal of Forestry Research 2018年第1期29卷 103-109页

作者： Ada Mudhanganyi Hilton G.T.Ndagurwa carlton Maravanyika Robert Mwase Department of Forest Resources and Wildlife Management Faculty of Applied Science National University of Science and Technology Forest Ecology Laboratory Faculty of Applied ScienceNational University of Science and Technology Stapleford Forest Allied Timbers Limited

Hydrogel amendments have been used to improve seedling survival and establishment particularly in dry environments. However, their effect on survival and growth of newly transplanted seedlings under varying water stress conditions is poorly known. In this regard, we examined the effects of Aqua Matrix Forestry~？, a potassium-based water-absorbent polymer, on the survival and early growth of Pinus patula seedlings planted in early-,mid-and late-dry season in the eastern highlands of Zimbabwe. The late-dry season was hotter and received more rainfall than the early-and mid-dry season. Hydrogel increased seedling survival by 34 and 22% in the mid-and late-dry season, respectively. Also, hydrogel-treated seedlings were significantly taller than untreated seedlings（P ／ 0.001）. The height to root collar diameter ratio of hydrogel-treated seedlings was greater than that of untreated seedlings only in the mid-dry season. In conclusion, increase in survival and early growth of hydrogel-treated seedlings suggests that hydrogels can be used to extend planting beyond the rainy season to include the dry months, a feat previously unattainable due to high seedling mortality. Further, these findings reflect similar findings with other hydrogels, suggesting that improved seedling survival and plant performance may be a general consequence of hydrogel amendments.

关键词： Hydrogel Pinus patula Reforestation Seedling Survival

Effect of preparation conditions on properties of Al-substituted α-Ni(OH)_2 prepared by homogeneous precipitation

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中国有色金属学会会刊：英文版 2005年第3期15卷 653-660页

作者：张倩徐艳辉王晓琳何国荣 Department of chemical engineering Tsinghua University Beijing 100084 China Fuel science Laboratory faculty of Mechanic engineering and Production Hamburg University of Applied Sciences 20099 Hamburg Germany

Al-substituted α-Ni（OH）2 was synthesized under different reaction conditions by a homogeneous precipitation method. The effect of reaction temperature, reaction time, Ni and Al ions concentration and reagent ratio on the physico-chemical properties and electrochemical performance of Al-substituted α-Ni（OH）2 was studied. The Al-substituted α-Ni（OH）2 samples were characterized by X-ray diffractometry（XRD）, infrared spectrometry（FT-IR）, inductively coupled plasma（IcP）, thermogravimetry（TG） and electrochemical test. The results reveal that the physico-chemical properties and electrochemical performance of the sample are influenced strongly by the preparation conditions. Keeping reaction temperature at 100 or 104℃ is appropriate and the largest specific discharge capacity of the sample is 320mA·h/g. With the reaction time increasing, the discharge capacity increases first and then decreases slightly. It is appropriate that the Ni and Al ions concentration and the ratio of urea to Ni and Al ions are 0.42mol/L and 0.75∶1, respectively.

关键词：同源沉淀法氢氧化镍镍锰电池点化学性质

Estimation and feedback control of air-fuel ratio for gasoline engines

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control Theory and Technology 2015年第2期13卷 151-159页

作者： Madan KUMAR Tielong SHEN Department of engineering and applied science Sophia University

In 4-stroke internal combustion engines, air-fuel ratio control is a challenging task due to the rapid changes of engine throttle,especially during transient operation. To improve the transient performance, managing the cycle-to-cycle transient behavior of the mass of the air, the fuel and the burnt gas is a key issue due to the imbalance of cyclic combustion process. This paper address the model-based estimation and control problem for cyclic air-fuel ratio of spark-ignition engines. A discrete-time model of air-fuel ratio is proposed, which represents the cycle-to-cycle transient behavior of in-cylinder state variables under the assumptions of cyclic measurability of the total in-cylinder charge mass, combustion efficiency and the residual gas fraction. With the model,a Kalman filter-based air-fuel ratio estimation algorithm is proposed that enable us to perform a feedback control of air-fuel ratio without using lambda sensor. Finally, experimental validation result is demonstrated to show the effectiveness of proposed estimation and control scheme that is conducted on a full-scaled gasoline engine test bench.

关键词： Discrete-time model AFR estimation using Kalman filter in-cylinder charge combustion efficiency PI controller

Effects of Froude number and geometry on water entry of a 2-D ellipse

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Journal of Hydrodynamics 2018年第4期30卷 738-749页

作者：张旭刘沛清屈秋林王睿 Ramesh K.Agarwal School of Aeronautic science and engineering Beihang University School of engineering and applied science Washington University in St.Louis

By using the finite volume method with volume of fluid model and global dynamic mesh technique, the effects of Froude number and geometry on the water entry process of a 2-D ellipse are investigated numerically. For the time history of the vertical force, the computational fluid dynamics（cFD） results match the experimental data much better than the classical potential-flow theories due to the consideration of the viscosity, turbulence, surface tension, gravity, and compressibility. The results show that the position of peak pressure on ellipse shifts from the spray root to the bottom of ellipse at a critical time. The critical time changes with the geometry and Froude number. By studying the vertical force, the ellipse water entry process can be divided into the initial and late stages based on the critical dimensionless time of about 0.1. The geometry of the ellipse plays a dominant role in the initial stage, while the Froude number is more important in the late stage of entry. The classical Wagner theory is extended to the ellipse water entry, and the predicted maximum value of vertical force coefficient in the initial stage is 4？a/b that matches the cFD results very well, where a and b are the horizontal axis and vertical axis of the ellipse parallel and perpendicular to the initial calm water surface, respectively.

关键词： Water impact water entry fluid-structure interaction Froude number