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Chinese Chemical Letters 2011年第6期22卷 738-740页

作者： Hai Yang Liu kun Wang Hai Yan Fu mao Lin Yuan Hua Chen Rui Xiang Li Key Lab of Green Chemistry and Technology Ministry of Education the Institute of Homogeneous Catalysis College of Chemistry Sichuan University Chengdu 610064 China

Amide,which is derived from proline and is inexpensive and air-stable,has been synthesized and characterized by ~1H NMR,^（13）C NMR,and *** was found to be an efficient ligand in the palladium-catalyzed Suzuki cross-coupling *** the Pd/amide catalytic system,aryl bromides can be coupled with phenylboronic acid in ethanol/water（1：2;v/v） in excellent yields even with a low Pd loading of 0.01 mol%.Moreover,the scope of the reaction is broad,and a wide variety of functional groups are tolerant.

关键词： Suzuki cross-coupling Palladium catalyst Aryl bromides Amide Water

Clinical presentations of gastric small gastrointestinal stromal tumors mimics functional dyspepsia symptoms

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World Journal of Gastroenterology 2014年第33期20卷 11800-11807页

作者： Qing-Xiang Yu Zhan-kun He Jiang Wang Chao Sun Wei Zhao Bang-mao Wang Department of Gastroenterology Tianjin Medical University General Hospital

AIM: To explore whether clinical presentations of gastric small gastrointestinal tumors (GISTs) mimics gastrointestinal dyspepsia symptoms.

关键词： Gastric small gastrointestinal stromal tumor Gastric leiomyoma Clinical presentation Endoscopic ultrasonography

Wing/body kinematics measurement and force and moment analyses of the takeoff flight of fruitflies

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Acta Mechanica Sinica 2014年第4期30卷 495-506页

作者： mao-Wei Chen mao Sun Ministry-of-Education Key Laboratory of Fluid Mechanics Beihang University

In the paper, we present a detailed analysis of the takeoff mechanics of fruitflies which perform voluntary takeoff flights. Wing and body kinematics of the insects during takeoff were measured using Based on the measured data, high-speed video techniques. inertia force acting on the insect was computed and aerodynamic force and moment of the wings were calculated by the method of computational fluid dynamics. Subtracting the aerodynamic force and the weight from the inertia force gave the leg force. The following has been shown. In its voluntary takeoff, a fruitfly jumps during the first wingbeat and becomes airborne at the end of the first wingbeat. When it is in the air, the fly has a relatively large ＂initial＂ pitch-up rotational velocity （more than 5 000~/s） resulting from the jumping, but in about 5 wingbeats, the pitch-up rotation is stopped and the fly goes into a quasi-hovering flight. The fly mainly uses the force of jumping legs to lift itself into the air （the force from the flapping wings during the jumping is only about 5%-10% of the leg force）. The main role played by the flapping wings in the takeoff is to produce a pitch-down moment to nullify the large ＂initial＂ pitch-up rotational velocity （otherwise, the fly would have kept pitching-up and quickly fallen down）.

关键词： Fruitfly· Takeoff flight ·Body and wing kine-matics Aerodynamic and leg forces

Controllable selective anchoring of subnanometric Ru clusters or single-atoms/clusters on tungsten nitride for the hydrogen oxidation

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Science China Chemistry 2024年第11期67卷 3749-3756页

作者： Qijiao Sun Chuanqiang Wu Yiqiang Sun Yuan Shen Lei Zhao Xiaodong Yang Li Yang Yunxiang Lin Keke mao kun Xu School of Chemistry and Chemical Engineering Key Laboratory of Functional Inorganic Material Chemistry of Anhui ProvinceAnhui Province Key Laboratory of Chemistry for Inorganic/Organic Hybrid Functionalized MaterialsKey Laboratory of Structure and Functional Regulation of Hybrid Materials of Ministry of EducationAnhui UniversityHefei 230601China Information Materials and Intelligent Sensing Laboratory of Anhui Province Institutes of Physical Science and Information TechnologyAnhui UniversityHefei 230601China School of Chemistry and Chemical Engineering University of JinanJinan 250022China School of Energy and Environment Anhui University of TechnologyMa’anshan 243032China

The impregnation method in the preparation of metal cluster catalysts typically inadvertently introduces single atoms(SAs) into the substrate. However, the question of whether the introduction of SAs will further improve the catalytic activity of cluster systems for specific reactions such as the hydrogen oxidation reaction(HOR) remains unraveled. Herein, we demonstrate Ru clusters anchored on WN nanowires(RuC/WN) show a higher alkaline HOR catalytic activity in comparison with Ru SAs and nanoclusters(NCs)-coupled catalyst anchored on WN nanowires system(RuC,S/WN). Notably, the RuC/WN exhibits superb intrinsic catalytic activity with a mass-normalized exchange current density of 890 m A mg^(-1)PGM, which is among the top level of well developed Ru-based HOR catalysts. Both theoretical simulation and experimental investigation suggest that RuC/WN owns an optimized H^(*)and OH^(*) reaction intermediates for the alkaline HOR, therefore resulting in the excellent intrinsic HOR catalytic performance.

关键词： hydrogen oxidation reaction Ru cluster catalyst Ru single atoms and nanoclusters coupled catalyst tungsten nitride substrate

Lithological Facies Classification Using Attention-Based Gated Recurrent Unit

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Tsinghua Science and Technology 2024年第4期29卷 1206-1218页

作者： Yuwen Liu Yulan Zhang Xingyuan mao Xucheng Zhou Jingwen chang Wenwei Wang Pan Wang Lianyong Qi College of Computer Science and Technology China University of Petroleum(East China)Qingdao 266580China Shandong Provincial University Laboratory for Protected Horticulture Weifang University of Science and TechnologyShouguang 262700China School of Mechanical Electrical and Information EngineeringShandong UniversityWeihai 264209China Shandong Provincial Key Laboratory of Network Based Intelligent Computing University of JinanJinan 250022China School of Modern Posts Nanjing University of Posts and TelecommunicationsNanjing 210023China

Lithological facies classification is a pivotal task in petroleum geology, underpinning reservoir characterization and influencing decision-making in exploration and production operations. Traditional classification methods, such as support vector machines and Gaussian process classifiers, often struggle with the complexity and nonlinearity of geological data, leading to suboptimal performance. Moreover, numerous prevalent approaches fail to adequately consider the inherent dependencies in the sequence of measurements from adjacent depths in a well. A novel approach leveraging an attention-based gated recurrent unit (AGRU) model is introduced in this paper to address these challenges. The AGRU model excels by exploiting the sequential nature of well-log data and capturing long-range dependencies through an attention mechanism. This model enables a flexible and context-dependent weighting of different parts of the sequence, enhancing the discernment of key features for classification. The proposed method was validated on two publicly available datasets. Results demonstrate a considerably improvement over traditional methods. Specifically, the AGRU model achieved superior performance metrics considering precision, recall, and F1-score.

关键词： attention mechanism facies classification GRU MLP(multilayer perceptron)

Novel strategy of constructing fluorescent probe for mao-B via cascade reaction and its application in imaging mao-B in human astrocyte

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Chinese Chemical Letters 2019年第1期30卷 71-74页

作者： Huihuan Qin Lingling Li kun Li Xiaoqi Yu Key Laboratory of Green Chemistry and Technology Ministry of Education College of Chemistry Sichuan University

To detect monoamine oxidase B(mao-B), the level of which is one of the most important indicators of neurodegenerative diseases such as Parkinson's disease, a new type of cascade reaction based on the formation of coumarin was applied in this research. After the reaction with mao-B, the protecting group of hydroxyl group in probes(DEAN-MA and DEAB-MA) was removed, and the fluorescence intensity significantly increased(l_(em) 456 nm) as the structure of coumarin was formed subsequently. The probes showed excellent sensitivity and selectivity to mao-B. The detection limit of DEAN-MA and DEAB-MA were 0.6ng/mL and 0.2 ng/mL, respectively. We succeeded in detecting mao-B in vitro and imaging it in human astrocyte(U87).

关键词： Monoamine oxidase-B Fluorescent probe Covalent-assembly Coumarin Cell imaging

Toward high performance microwave absorber by implanting La_(0.8)CoO_(3)nanoparticles on rGO

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Journal of Materials Science & Technology 2024年第7期174卷 176-187页

作者： Li chang Yu-Ze Wang Xin-Ci Zhang Lin Li Hua-Zhang Zhai mao-Sheng Cao Key Laboratory for Photonic and Electronic Bandgap Materials Ministry of EducationSchool of Physics&Electronic EngineeringHarbin Normal UniversityHarbin 150025China School of Materials Science and Engineering Beijing Institute of TechnologyBeijing 100081China

The advent of“intelligent era”brings our life more convenience,but the electromagnetic radiation sur-rounding us not only greatly threatens human health,also makes information leakage and hidden trouble to national defense ***,it is very urgent to develop novel electromagnetic wave absorption materials with lightweight,strong absorption,tunable absorption frequency and broad band ***,a novel electromagnetic wave absorber is obtained by constructing La_(0.8)CoO_(3)-rGO nanocompos-ite,where La_(0.8)CoO_(3)nanoparticles are anchored on graphene nanosheets by the electrostatic interaction between GO and La_(0.8)CoO_(3).The effect of hybridization ratio of La_(0.8)CoO_(3)and rGO on microwave ab-sorption properties is carefully *** optimal reflection loss of La_(0.8)CoO_(3)-rGO nanocomposite can reach-62.34 dB with the maximum effective bandwidth of 6.08 GHz,presenting 48.78%and 245.45%increment compared to bare La_(0.8)CoO_(3)nanoparticles,*** effective absorption bandwidth covers a broad electromagnetic wave absorption band from Ku band to the C band by tailoring thickness of the absorbers from 2.4 mm to 4.4 *** fascinating electromagnetic wave absorption performance is attributed to the synergy effect of La_(0.8)CoO_(3)and rGO,which integrates magnetic and dielectric loss caused by resonance,conductance,relaxation,and scattering *** result confirms that La_(0.8)CoO_(3)-rGO nanocomposite is potential candidates toward high-efficiency microwave absorbers and provides a valuable pathway for designing high-performance microwave attenuation materials in the future.

关键词： Perovskite La_(0.8)CoO_(3)nanoparticles Graphene Nanocomposite Microwave absorbing Broad band absorption

Aortic heterogeneity across segments and under high fat/salt/glucose conditions at the single-cell level

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National Science Review 2020年第5期7卷 881-896页

作者： Dongxu He Aiqin mao chang-Bo Zheng Hao Kan Ka Zhang Zhiming Zhang Lei Feng Xin Ma Wuxi School of Medicine and School of Food Science and Technology Jiangnan University School of Biotechnology Jiangnan University School of Pharmaceutical Science and Yunnan Key Laboratory of Pharmacology for Natural Products Kunming Medical University

The aorta, with ascending, arch, thoracic and abdominal segments, responds to the heartbeat, senses metabolites and distributes blood to all parts of the body. However, the heterogeneity across aortic segments and how metabolic pathologies change it are not known. Here, a total of 216 612 individual cells from the ascending aorta, aortic arch, and thoracic and abdominal segments of mouse aortas under normal conditions or with high blood glucose levels, high dietary salt, or high fat intake were profiled using single-cell RNA sequencing. We generated a compendium of 10 distinct cell types, mainly endothelial(EC), smooth muscle (SMC), stromal and immune cells. The distributions of the different cells and their intercommunication were influenced by the hemodynamic microenvironment across anatomical segments,and the spatial heterogeneity of ECs and SMCs may contribute to differential vascular dilation and constriction that were measured by wire myography. Importantly, the composition of aortic cells, their gene expression profiles and their regulatory intercellular networks broadly changed in response to high fat/salt/glucose conditions. Notably, the abdominal aorta showed the most dramatic changes in cellular composition, particularly involving ECs, fibroblasts and myeloid cells with cardiovascular risk factor-related regulons and gene expression networks. Our study elucidates the nature and range of aortic cell diversity,with implications for the treatment of metabolic pathologies.

关键词： aorta single-cell RNA sequencing cardiovascular disease

Intercalated 2D nanoclay for emerging drug delivery in cancer therapy

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Nano Research 2017年第8期10卷 2633-2643页

作者： Yi Zhang Mei Long Peng Huang Huaming Yang Shi chang Yuehua Hu Aidong Tang Linfeng mao Department of Inorganic Materials School of Minerals Processing and Bioengineering Central South University Changsha 410083 China Xiangya Hospital Central South University Changsha 410078 China Hunan Key Laboratory of Mineral Materials and Application Central South University Changsha 410083 China School of Chemistry and Chemical Engineering Central South University Changsha 410083 China

Natural two-dimensional （2D） kaolinite nanoclay has been incorporated into an emerging drug delivery system. The basal spacing of the kaolinite nanoclay was expanded from 0.72 to 4.16 nm through the intercalation of various organic guest species of different chain lengths, which can increase the efficiency in drug delivery and reduce the toxicity of doxorubicin （DOX）. Original kaolinite （Kaolin） and the Kaolin intercalation compounds exhibited a high level of biocompatibility and very low toxicity towards cells of pancreatic cancer, gastric cancer, prostate cancer, breast cancer, colorectal cancer, esophageal cancer, and differentiated thyroid cancer. However, lung cancer and hepatocellular cancer cells need more strict compositional, structural, and morphological modulations for drug delivery carriers. DOX-Kaolin and the DOX-Kaolin intercalation compounds showed dramatically faster drug release in moderately acidic solution than in neutral condition, and exhibited enhanced therapeutic effects against ten model cancer cell cultures in a dose-dependent manner. The use of 2D nanoclay materials for a novel drug delivery system could feasibly pave a way towards high-performance nanotherapeutics, with superior antitumor efficacy and significantly reduced side effects.

关键词： cancer therapy nanoclay intercalation drug delivery biocompatibility

Effects of Mo on the Microstructure and Hydrogen Sorption Properties of Ti-Mo Getters

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Chinese Journal of Aeronautics 2007年第2期20卷 172-176页

作者： ZHOU Hong-guo WEI Xiu-ying mao chang-hui XIONG Yu-hua QIN Guang-rong Institute of the Advanced Electronic Materials Beijing General Research Institute for Non Ferrous Metal Beijing 100088 China

The effects of Mo on the microstructure evolution, porosity and hydrogen sorption properties of Ti-Mo getters are investigated in this work. The results show that the addition of Mo prolongs the densification process of Ti-Mo getters and results in a significant amount of sintered pores. With the Mo content increasing, the porosity of getters firstly increases reaching the maximum value as it attains about 7.5wt.%, and then drops. At the room temperature, the hydrogen sorption property of getters increases progressively with the Mo content increasing, but the tendency is not very clear before its content lies below 2.5wt.%. When the Mo content achieves about 7.5wt.%, the hydrogen sorption property proves to be the best. The discussion is made about the above mentioned phenomena inclusive of hydrogen sorption properties of getters under different activation conditions （from 500-750℃）.

关键词： Ti-Mo getter powder metallurgy microstructure hydrogen sorption property