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Preparation, Characterization and Catalytic Performance of La-SO_4^(2-)/SBA-15 in Esterification of Acetic Acid with n-Butanol

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Chemical Research in Chinese Universities 2008年第3期24卷 357-361页

作者： tian Zhi-ming DENG Qi-gang sun Hui zhao De-feng State Key Laboratory of Fine Chemicals Dalian University of Technology Dalian 116012 P. R. China College of Chemistry and Chemical Engineering of Qiqihar University Qiqihar 161006 P. R. China

La-SO42-/SBA-15 was synthesized with various amounts of lanthanum via incipient-wetness impregnation. Characterization was done by X-ray diffraction（XRD）, transmission electron micrographs（TEM）, nitrogen adsorption, FTIR spectroscopic analysis, thermogravimetric analysis, and the total amount of acidity of catalyst was estimated by TPD of NH3. The results indicate that lanthanum has been incorporated into SBA-15 molecular sieve. The prepared materials（La-SO42-/SBA-15） keep the highly ordered mesoporous two-dimensional hexagonal structure and do not change the mesoporous channel structure of the support SBA-15. The catalyst showed best catalytic activity in the synthesis of n-butyl acetate. The optimum conditions of the esterification by orthogonal experiments were studied： the molar ratio of n-butanol to acetic acid 1：1.2, the amount of catalyst 7.5%, reaction time 80 min. The yield of n-butyl acetate could reach 93.2% under the optimum conditions. The catalyst was recyclable, cost effective and environmental friendly.

关键词： SBA-15 molecular sieve La-SO462-/SBA-15 Catalysis n-Butyl acetate Esterification

UPLC-MS/MS高通量测定鸡粪中81种抗菌药物残留方法的建立

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农业环境科学学报 2025年第1期44卷 260-268页

作者：刘田赵芮敏李木子李泽慧孙瑞杨智和孙晓亮赵思俊宋翠平霍乃蕊山西农业大学动物医学学院山西晋中030031 中国动物卫生与流行病学中心山东青岛266032 北京农学院动物医学学院北京102206 天津农学院动物医学学院天津300384

通过比较、优化样品前处理方法,建立了一种超高效液相色谱-串联质谱法(UPLC-MS/MS)高通量、快速测定鸡粪中磺胺类、大环内酯类、喹诺酮类、四环素类等4类81种抗菌药物残留检测方法。样品经EDTA-Mcllvaine与10%乙腈/乙酸(5∶15,V/V)混合... 详细信息

通过比较、优化样品前处理方法,建立了一种超高效液相色谱-串联质谱法(UPLC-MS/MS)高通量、快速测定鸡粪中磺胺类、大环内酯类、喹诺酮类、四环素类等4类81种抗菌药物残留检测方法。样品经EDTA-Mcllvaine与10%乙腈/乙酸(5∶15,V/V)混合溶液提取,HLB固相萃取柱净化过柱后,在UPLC-MS/MS多反应监测模式下进行定性及定量分析。加标回收试验结果显示,鸡粪中81种药物在1.0~100.0μg·kg^(-1)范围内线性关系良好(R^(2)>0.99),检出限为1.0~2.5μg·kg^(-1),待测药物的回收率为60.24%~118.70%。该方法简单可靠,提取效果好,适用于鸡粪中多类抗菌药物残留的大批样品筛查和确证。

关键词：鸡粪超高效液相色谱-串联质谱法抗菌药物残留

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Cry1Ab rice does not impact biological characters and functional response of Cyrtorhinus lividipennis preying on Nilaparvata lugens eggs

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Journal of Integrative Agriculture 2015年第10期14卷 2011-2018页

作者： CHEN yang LAI feng-xiang sun Yan-qun HONG Li-ying tian Jun-ce ZHANG Zhi-tao FU Qiang State Key Laboratory of Rice Biology China National Rice Research Institute State Key Laboratory of Breeding Base for Zhejiang Sustainable Pest and Disease Control Institute of Plant Protection and Microbiology Zhejiang Academy of Agricultural Sciences

One concern about the use of transgenic plants is their potential risk to natural enemies. In this study, using the eggs of the rice brown planthopper, Nilaparvata lugens, as a food source, we investigated the effects of Cry1 Ab rice on the biological characteristics and functional response of an important predator Cyrtorhinus lividipennis. The results showed that the survival ability（adult emergence rate and egg hatching rate）, development（egg duration, nymphal developmental duration）, adult fresh weight, adult longevity and fecundity of C. lividipennis on Bt rice plants were not significantly different compared to those on non-Bt rice plants. Furthermore, two important parameters of functional response（instantaneous search rate and handling time） were not significantly affected by Bt rice. In conclusion, the tested Cry1 Ab rice does not adversely impact the biological character and functional response of C. lividipennis.

关键词： Bt rice safety assessment non-target organism natural enemy

Effects and mechanisms of fluorite on the co-reduction of blast furnace dust and seaside titanomagnetite

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International Journal of Minerals,Metallurgy and Materials 2017年第11期24卷 1201-1210页

作者： tian-yang Hu Ti-chang sun Jue Kou Chao Geng Yong-qiang zhao School of Civil and Resources Engineering University of Science and Technology Beijing Beijing 100083 China Key Laboratory of Ministry of Education of China for Efficient Mining and Safety of Metal Mines Beijing 100083 China

The co-reduction roasting and grinding-magnetic separation of seaside titanomagnetite and blast furnace dust was investigated with and without fluorite addition at a reduction roasting temperature of 1250°C for 60 min, a grinding fineness of-43 μm accounting for 69.02 wt% of the total, and a low-intensity magnetic field strength of 151 kA/m. The mineral composition, microstructure, and state of the roasted products were analyzed, and the concentrations of CO and CO_2 were analyzed in the co-reduction roasting. Better results were achieved with a small fluorite dosage(≤4 wt%) in the process of co-reduction. In addition, F^- was found to reduce the melting point and viscosity of the slag phase because of the high content of aluminate and silicate minerals in the blast furnace dust. The low moisture content of the blast furnace dust and calcic minerals inhibited the hydrolysis of CaF_2 and the loss of F^-. Compared with the blast furnace dust from Chengdeng, the blast furnace dusts from Jiugang and Jinxin inhibited the diffusion of F-when used as reducing agents, leading to weaker effects of fluorite.

关键词： seaside titanomagnetite blast furnace dust co-reduction roasting fluorite mechanisms

Bio-inspired Superhydrophobic Self-healing Surfaces with Synergistic Anticorrosion Performance

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Journal of Bionic Engineering 2020年第6期17卷 1196-1208页

作者： Xiaona yang Limei tian Wei Wang Yong Fan Jiyu sun Jie zhao Luquan Ren Key Laboratory of Bionic Engineering Minitry of EducationJilin UniversityChangchun 130022China College of Chemistry Jilin UniversiyChangchun 130022China

The past decade has witnessed significant efforts in addressing the global metallic corrosion challenge,with a focus on avoiding or mitigating huge economic losses incurred by corrosion and on the development of protective coatings on ***,a synergistic anticorrosion coating with both superhydrophobicity and self-healing properties was reported,through a facile replica molding method by mixing the polyvinylidene fluoride(PVDF)matrix with nano-sized SiO2 particles and 2-mercaptobenzothiazole(MBT)loaded halloysites(HNTs).The surface exhibits robust self-cleaning behavior under harsh conditions and high liquid repellence to withstand the osmosis of corrosive *** self-healing performance of the coating,due to the introduction of MBT-loaded HNTs,enhances the anticorrosion capability,which is still valid once the protective layer is *** polarization(PDP)and Electrochemical Impedance Spectroscopy(EIS)measurements demonstrate that the synergetic effects in anticorrosion performances significantly enhance the long-term corrosion protection of ***,this type of dual-action coating may find unique applications in metal corrosion resistance where both super-repellency and self-healing properties are desired.

关键词： superhydrophobic anticorrosion self-healing corrosion inhibitor

An In-Situ MRI Method for Quantifying Temperature Changes during Crystal Hydrate Growths in Porous Medium

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Journal of Thermal Science 2022年第5期31卷 1542-1550页

作者： ZHANG Lunxiang sun Mingrui WANG tian yang Lei ZHANG Xiaotong zhao Jiafei SONG Yongchen Key Laboratory of Ocean Energy Utilization and Energy Conservation of Ministry of Education School of Energy and Power EngineeringDalian University of TechnologyDalian116024China Interdisciplinary Institute of Neuroscience and Technology Zhejiang UniversityHangzhou310029China

Given the complexity of the thermo-hydro-chemically coupled phase transition process of hydrates,real-time in-situ observations are *** maps are particularly essential in analyzing the heat transfer process during the growth and dissociation of crystal *** this study,we present the temporally and spatially resolved thermometry of the formation of tetrahydrofuran hydrates based on the temperature dependence of the chemical shift of the water *** of temperature changes were synchronously obtained using a 9.4 T^(1)H magnetic resonance imaging(MRI)system to predict the saturation level of the aqueous solution,phases of the solid hydrates,and the positive temperature anomaly of the exothermic *** was observed that variations in the MRI signal decreased while the temperature rise differed significantly in space and *** results predicted in this study could have significant implications in optimizing the phase transition process of gas hydrates.

关键词： hydrate phase transition heat transfer porous medium temperature mapping magnetic resonance imaging thermometry thermodynamics and molecular-scale phenomena

Sand control mechanism of radial well filled with phase change material in hydrate reservoir

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Petroleum Science 2024年第4期21卷 2571-2582页

作者： Xiao-Qiang Liu Zhong-Xi Han Zhi-Lin Luo Hai-Long Lu ying sun qing You tian-Kui Guo Zhan-qing Qu School of Energy Resources China University of Geosciences(Beijing)Beijing10083China Beijing Key Laboratory of Unconventional Natural Gas Geological Evaluation and Development Engineering China University of Geosciences(Beijing)Beijing10083China China Research Institute of Petroleum Exploration and Development Beijing10083China Engineering Technology Research Institute of Southwest Oil&Gas Field Company PetroChinaChengdu610051SichuanChina Beijing International Center for Gas Hydrate School of Earth and Space SciencesPeking UniversityBeijing100871China School of Advanced Material Peking University Shenzhen Graduate SchoolShenzhen518055GuangdongChina School of Petroleum Engineering China University of Petroleum(East China)Qingdao266580shandongChina

Radial well filled with phase change material has been proposed as a novel sand control method for hydrate *** order to reveal the sand control mechanism,CFD-DEM coupling method is applied to simulate the migration,settlement,and blockage processes of sand particles in the radial *** obtained results indicate that three scenarios have been recognized for sand particles passing through sand control medium,based on the diameter ratio of sand control medium to sand particle(D_(d)):fully passing(D_(d)=8.75-22.5),partially passing and partially blocked(D_(d)=3.18-5.63),and completely blocked(D_(d)=2.18-3.21).After being captured by the sand control medium,sand particles can block pores,which increases fluid flow resistance and causes a certain pressure difference in the radial *** pressure in the radial well should be lower than the hydrate phase equilibrium pressure during sand control design,for the purpose of promoting hydrate decomposition,and sand *** length of the radial well should be optimized based on the reservoir pore pressure,production pressure difference,bottom hole pressure,and the pressure gradient in the radial *** should be noticed that the sand control medium leads to a decrease in permeability after sand particles *** the permeability is reduced to several hundred millidarcy,it is still sufficient to ensure the effective flow of gas and water after hydrate *** fluid velocity reduces the blocking capacity of the sand control medium,mainly because of deterioration in bridging between sand particles.

关键词： Hydrate reservoir Sand control Radial well CFD-DEM

A Fast Clustering Based Evolutionary Algorithm for Super-Large-Scale Sparse Multi-Objective Optimization

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IEEE/CAA Journal of Automatica Sinica 2023年第4期10卷 1048-1063页

作者： Ye tian Yuandong feng Xingyi Zhang Changyin sun Key Laboratory of Intelligent Computing and Signal Processing of Ministry of Education Institutes of Physical Science and Information TechnologyAnhui UniversityHefei 230601China School of Computer Science and Technology Anhui UniversityHefei 230601China School of Artificial Intelligence Anhui UniversityHefei 230601China School of Automation Southeast UniversityNanjing 210096China

During the last three decades,evolutionary algorithms(EAs)have shown superiority in solving complex optimization problems,especially those with multiple objectives and non-differentiable ***,due to the stochastic search strategies,the performance of most EAs deteriorates drastically when handling a large number of decision *** tackle the curse of dimensionality,this work proposes an efficient EA for solving super-large-scale multi-objective optimization problems with sparse optimal *** proposed algorithm estimates the sparse distribution of optimal solutions by optimizing a binary vector for each solution,and provides a fast clustering method to highly reduce the dimensionality of the search *** importantly,all the operations related to the decision variables only contain several matrix calculations,which can be directly accelerated by *** existing EAs are capable of handling fewer than 10000 real variables,the proposed algorithm is verified to be effective in handling 1000000 real ***,since the proposed algorithm handles the large number of variables via accelerated matrix calculations,its runtime can be reduced to less than 10%of the runtime of existing EAs.

关键词： Evolutionary computation fast clustering sparse multi-objective optimization super-large-scale optimization

Artificial intelligence-assisted repair of peripheral nerve injury: a new research hotspot and associated challenges

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Neural Regeneration Research 2024年第3期19卷 663-670页

作者： yang Guo Liying sun Wenyao Zhong Nan Zhang Zongxuan zhao Wen tian Department of Hand Surgery Beijing Jishuitan HospitalBeijingChina

Artificial intelligence can be indirectly applied to the repair of peripheral nerve ***,it can be used to analyze and process data regarding peripheral nerve injury and repair,while study findings on peripheral nerve injury and repair can provide valuable data to enrich artificial intelligence *** investigate advances in the use of artificial intelligence in the diagnosis,rehabilitation,and scientific examination of peripheral nerve injury,we used CiteSpace and VOSviewer software to analyze the relevant literature included in the Web of Science from 1994–*** identified the following research hotspots in peripheral nerve injury and repair:(1)diagnosis,classification,and prognostic assessment of peripheral nerve injury using neuroimaging and artificial intelligence techniques,such as corneal confocal microscopy and coherent anti-Stokes Raman spectroscopy;(2)motion control and rehabilitation following peripheral nerve injury using artificial neural networks and machine learning algorithms,such as wearable devices and assisted wheelchair systems;(3)improving the accuracy and effectiveness of peripheral nerve electrical stimulation therapy using artificial intelligence techniques combined with deep learning,such as implantable peripheral nerve interfaces;(4)the application of artificial intelligence technology to brain-machine interfaces for disabled patients and those with reduced mobility,enabling them to control devices such as networked hand prostheses;(5)artificial intelligence robots that can replace doctors in certain procedures during surgery or rehabilitation,thereby reducing surgical risk and complications,and facilitating postoperative *** artificial intelligence has shown many benefits and potential applications in peripheral nerve injury and repair,there are some limitations to this technology,such as the consequences of missing or imbalanced data,low data accuracy and reproducibility,and ethical issues(e.g.,privac

关键词： artificial intelligence artificial prosthesis medical-industrial integration brain-machine interface deep learning machine learning networked hand prosthesis neural interface neural network neural regeneration peripheral nerve