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Science China Chemistry 2024年第11期67卷 3833-3843页

作者： Zhaodong Zhu jingjing wu Frontiers Science Center for Transformative Molecules Shanghai Key Laboratory for Molecular Engineering of Chiral DrugsSchool of Chemistry and Chemical EngineeringZhangjiang Institute for Advanced StudyShanghai Jiao Tong UniversityShanghai 200240China

Based on rational design, benzoyl cyanide, a well-known ionic acylating reagent, has been developed as a general radical acylating reagent for benzylic site-selective acylation reactions for the first time. Using visible-light photoredox-catalyzed single electron transfer(SET) and hydrogen atom transfer(HAT) strategies, two different direct benzylic C–H acylation reactions with high atom economy have been developed. This newly developed radical acylating reagent could also be used to achieve three component acyltrifluoromethylation of styrenes, which is usually challenging to achieve by other means. All of these reactions proceed under mild nickel-free and NHC-free conditions with high functional group tolerance. In addition, based on our detailed mechanistic experiments, the process of radical-radical cross-coupling mechanism was suggested for these transformations.

关键词： photoredox catalysis benzylic C–H acylation radical acylating reagent HAT catalysis acyltrifluoromethylation

BF3•Et2O Promoted Sulfuration of Steroidal Sapogenins

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Chinese Journal of Chemistry 2015年第6期33卷 632-636页

作者： Jun Wang jingjing wu Weisheng Tian Shanghai Institute of Organic Chemistry Chinese Academy of SciencesShanghai 200032China Department of Chemistry South University of Science and TechnologyShenzhenGuangdong 518055China

A reaction between steroidal sapogenins and hydrogen sulfide promoted by BF3•Et2O is *** thio-diosgenin and thiotigogenin comprising a sulfur atom on the F ring can be easily afforded in one step under this mild react... 详细信息

关键词： steroidal sapogenin hydrogen sulfide sulfuration spiroketal resource chemistry

Defective NH_(2)-UiO-66(Zr) effectively converting CO_(2) into cyclic carbonate under ambient pressure,solvent-free and co-catalyst-free conditions

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Chinese Journal of Chemical Engineering 2022年第3期35卷 222-229页

作者： Xueting Liu Chunhui Hu jingjing wu Peng Cui Fengyu Wei School of Chemistry and Chemical Engineering Hefei University of TechnologyAnhui Key Laboratory of Controllable Chemical Reaction&Material Chemical EngineeringHefei 230009China

In this study,a series of metal-organic frameworks(MOFs)NH_(2)-UiO-66-x HAc catalysts were synthesized by solvothermal method using acetic acid(HAc)as a modulator,and were applied to the cycloaddition of CO_(2)and epichlorohydrin(EPIC)under ambient *** of the modulation by HAc on morphologies and structures of the MOFs are demonstrated via PXRD,FESEM,FTIR,N_(2)adsorption-desorption,XPS and ^(1)H NMR *** results show that the MOFs containing mesoporous pores can be prepared by adjusting the concentration of *** optimizing the amount of HAc added,the specific surface area of NH_(2)-UiO-66-8 HAc is as high as 879.17 m^(2)·g^(-1),which is 28.3%higher than that of the original *** the evaluation of catalytic performance showed that HAc modulation enhanced the activity of NH_(2)-UiO-66-x HAc under mild *** exposure of Lewis acid sites,increased specific surface area and porosity via the modulation of HAc defective ligand can be supposed the key factors to determine the enhanced catalytic *** addition,considering the influence of gas concentration on the reaction,the concept of TOP(Turnover of Pressure,defined as the mass of conversions of a unit mass catalyst under unit pressure and unit time)was first proposed in this article.

关键词： CO_(2)conversion Metal-organic frameworks Acetic acid modulation Defect Mild conditions

One-pot Three Component Synthesis of Polyfluoroarylated Arylacetates via VNSAr-SNAr Reaction

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Chinese Journal of Chemistry 2012年第12期30卷 2747-2751页

作者： Xiong Yang wu jingjing Xiao Senhan Cao Song Shanghai Key Laboratory of Chemical Biology School of Pharmacy East China University of Science and Technology Shanghai 200237 China School of Chemical and Environmental Engineering Shanghai Institute of Technology Shanghai 201418 China

A series of 2-polyfluoroaryl arylacetates were synthesized by a one-pot three-component VNSAr-SNAr reaction of polyfluoroarenes, ethyl 2-chloropropionate, and ortho-substituted nitrobenzenes.

关键词： 2-polyfluoroaryl arylacetates three-component reaction VNSAr-SNAr reaction functionalization of theC-F bond

Two-dimensional transition metal chalcogenide nanomaterials for cancer diagnosis and treatment

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Chinese Chemical Letters 2022年第10期33卷 4437-4448页

作者： jingjing wu Tingting Hu Guoping Zhao Anran Li Ruizheng Liang State Key Laboratory of Chemical Resource Engineering Beijing Advanced Innovation Center for Soft Matter Science and EngineeringBeijing University of Chemical TechnologyBeijing 100029China Beijing Advanced Innovation Center for Big Data-Based Precision Medicine School of Engineering MedicineBeihang UniversityBeijing 100191China Department of Orthopedics Guilin People's HospitalGuilin 541002China

For more than a decade,the exfoliation of graphene and other layered materials has led to a tremendous amount of research in two-dimensional(2D)materials,among which 2D transition metal chalcogenides(TMCs)nanomaterials have attracted much attention in a wide range of applications including photoelectric devices,lithium-ion batteries,catalysis,and energy conversion and storage owing to their unique photoelectric physical *** such large specific surface area,strong near-infrared(NIR)absorption and abundant chemical element composition,2D TMCs nanomaterials have become good candidates in biomedical imaging and cancer *** review systematically summarizes recent progress on 2D TMCs nanomaterials,which includes their synthesis methods and applications in cancer *** the end of this review,we also highlight the future prospects and challenges of 2D TMCs *** is expected that this work can provide the readers with a detailed overview of the synthesis of 2D TMCs and inspire more novel functional biomaterials based on 2D TMCs for cancer treatment in the future.

关键词： Two-dimensional(2D)nanomaterials Transition metal chalcogenides(TMCs) Synthesis method Biomedical imaging Cancer treatment

Influencing assessment of different heating modes on thermal comfort in electric vehicle cabin

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Energy and Built Environment 2024年第4期5卷 556-567页

作者： jingjing wu Jianlin Liu Jingde Zhao Yun Su College of Environmental Science and Engineering Donghua UniversityShanghaiChina College of Fashion and Design Donghua UniversityShanghaiChina

Electric vehicle(EV)is more environmental-friendly than gasoline vehicle because the main power is not *** the heating system,the waste heat generated by engines is recycled to heat the cabin of gasoline ones,while the EV need extra electric energy consumption for heating the cabin which decreases the driving *** comfort system(PCS)has been reported that it is an alternative technique to improve occupant thermal comfort and indirectly save building heating *** study aims to investigate the occupants’thermal sensation under four heating modes in the EV cabin in winter,including no heating,only PCS,only air conditioning,and both air conditioning and *** field survey is conducted in a parked EV with 12 *** thermal comfort indexes(PMV,SET^(*),and operative temperature Top)are used and assessed for their applicability in the thermal environment of the *** show that the thermal environment in the cabin is non-uniform and dynamic with the air conditioning mode,while the PCS mode just slightly affects the temperature differences ***,the subjects’thermal sensations cannot maintain neutral or warmer under the PCS mode *** results of PMV are lower than the subjects’actual thermal sensation votes(TSV),while the results of SET^(*)and Top show significant linear relationships with the TSV for the correlation coefficients above *** to the air conditioning mode,the neutral SET^(*)and neutral Top are decreased by 2.7℃ and 1.6℃ under the mode with PCS and air conditioning,*** findings indicate that PCS not only has a positive effect on improving the cabin environment and occupant’s thermal sensation but also has the potential to lower the setting temperature of air conditioner of EVs in winter.

关键词： Electric vehicle Personal comfort system(PCS) Thermal sensation votes(TSV) Standard effective temperature(SET∗)

Comparison of dynamic adsorption/desorption characteristics of toluene on different porous materials

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Journal of Environmental Sciences 2012年第3期24卷 520-528页

作者： Weiwei Zhang Zhenping Qu Xinyong Li Yi Wang Ding Ma jingjing wu Key Laboratory of Industrial Ecology and Environmental Engineering(MOE) School of Environmental Science and TechnologyDalian University of TechnologyDalianLinggong 116024China State Key Laboratory of Catalysis Dalian Institute of Chemical PhysicsChinese Academy of SciencesDalian 116023China

Four different types of adsorbents, SBA-15, MCM-41, NaY and SiO2, were used to study the dynamic adsorption/desorption of toluene. To further investigate the influence of pore structure on its adsorption performance, two SBA-15 samples with different microspores were also selected. It is shown that microporous material NaY has the largest adsorption capacity of 0.2873 mL/g, and the amorphous SiO2 exhibits the least capacity of 0.1003 mL/g. MCM-41 also shows a lower break through capacity in spite of the relatively small pore diameter, because it can not provide the necessary small geometric confinement for the tiny adsorbates. However, the mesoporous SBA-15 silica with certain micropore volume shows relatively higher adsorption capacity than that of MCM-41 silica. The presence of micropores directly leads to an increase in the dynamic adsorption capacity of toluene. Although NaY has the highest adsorption capacity for toluene, its complete desorption temperature for toluene is high （〉 350°C）, which limits its wide application. On the contrary, mesoporous silica materials exhibits a good desorption performance for volatile organic compounds at lower temperatures. Among these materials mesoporous SBA-15 samples, with a larger amount micropores and a lower desorption temperature, are a potentially interesting adsorbent for the removal of volatile organic compounds. This behavior should been related with the best synergetic effect of mesopores and micropores.

关键词： dynamic adsorption/desorption mesopores micropores toluene

社交媒体使用、媒介素养与新型职业农民创新意愿

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北京科技大学学报（社会科学版） 2025年第1期41卷 89-100页

作者：谢桂花黄美娇吴晶晶福建商学院工商管理学院福州350012

农村创新创业活动的开展首先要激发新型职业农民的创新意愿。然而,当前对社交媒体与新型职业农民创新意愿关系的研究仍显薄弱。基于367位新型职业农民样本,文章尝试以创新扩散理论和计划行为理论为基础构建研究模型,探索社交媒体使用、... 详细信息

农村创新创业活动的开展首先要激发新型职业农民的创新意愿。然而,当前对社交媒体与新型职业农民创新意愿关系的研究仍显薄弱。基于367位新型职业农民样本,文章尝试以创新扩散理论和计划行为理论为基础构建研究模型,探索社交媒体使用、媒介素养和新型职业农民创新意愿之间的关系。研究结果表明:新型职业农民的社交媒体使用不仅可以直接促进其创新意愿的提升,也可以通过创新主观规范和感知创新行为控制中介变量发挥作用;社交媒体使用对影响新型职业农民创新的主观因素和客观因素具有正面效应;新型职业农民的媒介素养在此过程中起到了积极的调节作用,强化了社交媒体使用与创新态度、创新主观规范和感知创新行为控制之间的关系。

关键词：新型职业农民社交媒体使用媒介素养创新意愿

Effect of O–O bonds on p-type conductivity in Ag-doped ZnO twin grain boundaries

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Chinese Physics B 2018年第5期27卷 487-491页

作者： jingjing wu Xin Tang Fei Long Biyu Tang Key Laboratory of New Processing Technology for Nonferrous Metal&Materials Ministry of EducationGuilin University of TechnologyGuilin 541004China College of Material Science and Engineering Guilin University of TechnologyGuilin 541004China School of Chemistry&Chemical Engineering Guangxi UniversityNanning 530004China

Based on density functional theory,first-principles calculation is applied to study the electronic properties of undoped and Ag-doped Zn O-Σ7(123^-0)twin grain boundaries(GBs).The calculated result indicates that the twin GBs can facilitate the formation and aggregation of Ag substitution at Zn sites(AgZn)due to the strain ***,some twin GBs can also lower the ionization energy of *** density of state shows that the O–O bonds in GBs play a key role in the formation of a shallow acceptor energy *** AgZnbonds with one O atom in the O–O bond,the antibonding state of the O–O bond becomes partially *** a result,a weak spin splitting occurs in the antibonding state,which causes a shallow empty energy level above the valence band ***,the model can be applied to explain the origin of p-type conductivity in Ag-doped Zn O.

关键词： ZnO twin grain boundary first-principles calculation ligand field theory

Automated X-ray recognition of solder bump defects based on ensemble-ELM

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Science China(Technological Sciences) 2019年第9期62卷 1512-1519页

作者： SU Lei WANG LingYu LI Ke wu jingjing LIAO GuangLan SHI TieLin LIN TingYu Jiangsu Key Laboratory of Advanced Food Manufacturing Equipment and Technology Jiangnan UniversityWuxi 214122China State Key Laborotary of Digital Manufacturing Equipment and Technology Huazhong University of Science and TechnologyWuhan 430074China School of Mechanical Engineering Zhejiang UniversityHangzhou 310027China National Center for Advanced Packaging Wuxi 214028China

Solder bumps realize the mechanical and electrical interconnection between chips and substrates in surface mount components,such as flip chip, wafer level packaging and three-dimensional integration. With the trend to smaller and lighter electronics,solder bumps decrease in dimension and pitch in order to achieve higher I/O density. Automated and nondestructive defect inspection of solder bumps becomes more difficult. Machine learning is a way to recognize the solder bump defects online and overcome the effect caused by the human eye-fatigue. In this paper, we proposed an automated and nondestructive X-ray recognition method for defect inspection of solder bumps. The X-ray system captured the images of the samples and the solder bump images were segmented from the sample images. Seven features including four geometric features, one texture feature and two frequency-domain features were extracted. The ensemble-ELM was established to recognize the defects intelligently. The results demonstrated the high recognition rate compared to the single-ELM. Therefore, this method has high potentiality for automated X-ray recognition of solder bump defects online and reliable.

关键词： automated recognition solder bump X-ray ensemble-ELM