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Mechanochemical Metal-Free Synthesis of 3-Arylindenones via Unprecedented Aryl Swapping

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Chinese Journal of Chemistry 2022年第21期40卷 2539-2545页

作者： Liang Li Chuang Niu guan-wu wang Hefei National Research Center for Physical Sciences at the Microscale and Department of Chemistry University of Science and Technologyof ChinaHefeiAnhui230026China Department of Chemistry and Chemical Engineering Hefei Normal UniversityHefeiAnhui 230601China

A triflic anhydride-induced annulation of benzoic acids bearing electron-withdrawing groups with arylalkynes leading to diverse 3-arylindenones via an unprecedented aryl swapping pathway under an air atmosphere and ball-milling conditions has been *** of the obtained 3-arylindenones are fluorine-containing *** present mechanochemical protocol employs easily available and inexpensive benzoic acids,which unexpectedly undergo aryl swapping with arylalkynes and serve as the source of the 3-aryl *** current mechanochemical methodology shows advantages including no requirement of transition-metal catalysts,ambient conditions and excellent regioselectivity for the rearrangement products,providing expedient access to 3-arylindenones containing functional groups such as F,Cl,Br,CF3,OCF3,SCF3,OAc,Ac,CO_(2)Et or NO_(2).

关键词： Mechanochemistry Rearrangement 3-Arylindenones Carboxylic acids Alkynes Green chemistry

Tribocatalysis: challenges and perspectives

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Science China Chemistry 2021年第10期64卷 1609-1613页

作者： Feng-Ru Fan Shunji Xie guan-wu wang Zhong-Qun Tian State Key Laboratory of Physical Chemistry of Solid Surfaces Collaborative Innovation Center of Chemistry for Energy Materials(iChEM)College of Chemistry and Chemical EngineeringXiamen UniversityXiamen 361005China Hefei National Laboratory for Physical Sciences at Microscale CAS Key Laboratory of Soft Matter ChemistryCollaborative Innovation Center of Chemistry far Energy Materials(iChEM)Department of ChemistryUniversity of Science and Technology'of ChinaHefei 230026China

With an increasing global energy demands and environmental pollution, the development of alternative clean energy technologies has aroused widespread research *** and converting natural energy from the environment, such as solar energy, mechanical energy, thermal energy, chemical and biological energy, is one of the main sources of clean energy.

关键词： catalysis pollution energy

Solvent-free Synthesis of Dihydrofuran-fused [60]Fullerene Derivatives by High-speed Vibration Milling

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Chinese Chemical Letters 2005年第10期16卷 1327-1329页

作者： Xin CHENG guan wu wang Yasujiro MURATA Koichi KOMATSU Department of Chemistry University of Science and Technology of China Hefei 230026 Institute for Chemical Research Kyoto University Uji Kyoto 611-0011 Japan

Solvent-free reactions of 1, 3-cyclohexanedione, 5, 5-dimethyl-1, 3-cyclohexanedione, 2, 4-pentanedione and ethyl acetoacetate with C60 in the presence of Mn（OAc）3·2H2O and ceric ammonium nitrate （CAN） under the high-speed vibration milling conditions afforded dihydrofuran-fused C60 derivatives. CAN is the better oxidant than Mn（OAc）3·2H2O in these mechanochemical reactions.

关键词： Fullerene mechanochemical solvent-free 13-dicarbonyl compounds.

Regioselective Electrochemical Hydroalkylations of[60]Fullerene-Fused Furochromenone

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Chinese Journal of Chemistry 2023年第7期41卷 769-775页

作者： Zheng-Chun Yin Chuang Niu Mingjie Li Wen-Rui Liu guan-wu wang Hefei National Research Center for Physical Sciences at the Microscale and Department of Chemistry University of Science and Technology of ChinaHefeiAnhui230026 China State Key Laboratory of Applied Organic Chemistry Lanzhou UniversityLanzhouGansu730000 China

Comprehensive Summary Regioselective electrochemical hydroalkylations of[60]fullerene-fused furochromenone with alky halides under different acidic conditions unexpectedly afford three types of tetra-functionalized[60]fullerene derivatives in high *** acetic acid is used as the proton source,two 1,2,3,4-adducts with retained or rearranged five-membered heterocycle are obtained as major and minor products,*** trifluoroacetic acid is employed as the proton source,1,2,3,16-adducts and 1,2,3,4-adducts,both with the five-membered heterocycle rearranged from[6,6]-junction to[5,6]-junction,are ***,the obtained 1,2,3,16-adducts can be transformed into 1,2,3,4-adducts accompanied by rearrangement of the fused five-membered heterocycle from[5,6]-junction to[6,6]-*** products have been characterized by spectroscopic data and single-crystal X-ray ***,the two 1,2,3,4-adducts with the heterocycle fused to[5,6]-junction or[6,6]-junction show diagnostic UV-vis spectra,which may be useful for the identification of these two types of 1,2,3,4-adducts in the future.A plausible reaction mechanism has been proposed to elucidate the formation of hydroalkylation products in the presence of different acids.

关键词： Fullerenes Electrosynthesis Hydroalkylation Regioselectivity Rearrangement

Reduced magma generation and its implications for the Pulang giant porphyry Cu-polymetallic deposit in Northwest Yunnan,China

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Acta Geochimica 2024年第4期43卷 802-813页

作者： Jingwei guan Tao Ren Lei wang Shenjin guan Lianrong wu Baosheng Shi Faculty of Land Resources Engineering Kunming University of Science and TechnologyKunming 650093People’s Republic of China Diqing Nonferrous Metals Co. LtdShangri-La 674400People’s Republic of China

The Pulang giant porphyry Cu-Mo polymetallic deposit is located in the Zhongdian area in the center of the Sanjiang Tethys tectonic domain,which was formed by the westward subduction of the Garze-Litang oceanic slab beneath the Zhongza ***-pyrrhotite-pyritemolybdenite occurs as disseminations,veins,veinlets,and stockworks distributed in the K-silicate alteration zone in the monzonite porphyry,which is superimposed by *** chemical compositions of biotite and amphibole analyzed by electron probe microanalysis(EPMA)indicate that the ore-forming magma and exsolved fluids experienced a continuous decrease in the oxygen fugacity(fO_(2)).Primary amphibolite and biotite(type I)crystallized at relatively high temperatures(744-827°C)and low fO_(2)(log fO_(2)=−12.26 to−11.91)during the magmatic *** fluids exsolved from the magma have a relatively lower temperature(621-711°C)and fO_(2)(log fO_(2)=−14.36 to−13.32)than the original *** addition,the presence of a high abundance of pyrrhotite and an insufficiency of primary magnetite and sulfate in the ore(i.e.,anhydrite and gypsum)indicate that the deposit may be a reduced porphyry *** and fluid fO_(2)results,combined with previous research on magmatic fO_(2)at the Pulang deposit,indicate that the magma associated with the reduced Pulang ore assemblages was initially generated as a highly oxidized magma that was subsequently reduced by sedimentary rocks of the Tumugou Formation.

关键词： Porphyry deposit Oxygen fugacity(fO_(2)) Contamination of surrounding rock Pulang Zhongdian arc

Effect of Mn addition on microstructure and mechanical properties of GX40CrNiSi25-12 austenitic heat resistant steel

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China Foundry 2024年第3期21卷 205-212页

作者： guan-yu Jiang Meng-wu wu Xiao-guang Yang Hui wang Yu-yuan Zhu Hubei Key Laboratory of Advanced Technology for Automotive Components Wuhan University of TechnologyWuhan 430070China Hubei Longzhong Laboratory Xiangyang 441000HubeiChina Wescast Industries(China)Co. Ltd.Wuhan 430100China

Three types of steels were designed on the basis of GX40CrNiSi25-12 austenitic heat resistant steel by adding different Mn contents(2wt.%,6wt.%,and 12wt.%).Thermodynamic calculation,microstructure characterization and mechanical property tests were conducted to investigate the effect of Mn addition on the microstructure and mechanical properties of the austenitic heat resistant *** show that the matrix structure in all the three types of steels at room temperature is completely *** NbC and M_(23)C_(6)precipitate at grain boundaries of austenite *** the increase of Mn content,the number of carbides increases and their distribution becomes more *** the Mn content increases from 1.99%to 12.06%,the ultimate tensile strength,yield strength and elongation increase by 14.6%,8.0%and 46.3%,*** improvement of the mechanical properties of austenitic steels can be explained by utilizing classic theories of alloy strengthening,including solid solution strengthening,precipitation strengthening,and grain *** increase in alloy strength can be attributed to solid solution strengthening and precipitation strengthening caused by the addition of *** improvement of the plasticity of austenitic steels can be explained from two aspects:grain refinement and homogenization of precipitated phases.

关键词： austenitic heat resistant steel manganese microstructure mechanical properties

A blockchain based privacy-preserving federated learning scheme for Internet of Vehicles

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Digital Communications and Networks 2024年第1期10卷 126-134页

作者： Naiyu wang Wenti Yang Xiaodong wang Longfei wu Zhitao guan Xiaojiang Du Mohsen Guizani School of Control and Computer Engineering North China Electric Power UniversityChina Department of Mathematics&Computer Science Fayetteville State UniversityFayettevilleNCUSA Department of Electrical and Computer Engineering Stevens Institute of TechnologyHobokenNJ07030USA Department of Computer Science and Engineering Qatar UniversityDohaQatar

The application of artificial intelligence technology in Internet of Vehicles(lov)has attracted great research interests with the goal of enabling smart transportation and traffic ***,concerns have been raised over the security and privacy of the tons of traffic and vehicle *** this regard,Federated Learning(FL)with privacy protection features is considered a highly promising ***,in the FL process,the server side may take advantage of its dominant role in model aggregation to steal sensitive information of users,while the client side may also upload malicious data to compromise the training of the global *** existing privacy-preserving FL schemes in IoV fail to deal with threats from both of these two sides at the same *** this paper,we propose a Blockchain based Privacy-preserving Federated Learning scheme named BPFL,which uses blockchain as the underlying distributed framework of *** improve the Multi-Krum technology and combine it with the homomorphic encryption to achieve ciphertext-level model aggregation and model filtering,which can enable the verifiability of the local models while achieving ***,we develop a reputation-based incentive mechanism to encourage users in IoV to actively participate in the federated learning and to practice *** security analysis and performance evaluations are conducted to show that the proposed scheme can meet the security requirements and improve the performance of the FL model.

关键词： Federated learning Blockchain Privacy-preservation Homomorphic encryption Internetof vehicles

A method to determine the bonded-particle model parameters for simulation of ores

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Particuology 2024年第3期86卷 24-38页

作者： Shuwei wu Guoqiang wang Longfei Fan Wei guan Jianbo Guo Zhengbin Liu Yukuan wang School of Mechanical and Aerospace Engineering Jilin UniversityChangchun130025China

The bonded-particle model(BPM)is commonly used in the numerical analysis of ore *** improve the accuracy of simulating the mechanical process of ore process of ore crushing in a crusher,the parameters of the BPM for the ore must be *** this study,a calibration method was proposed for the scientific determination of the parameters of the BPM for ore undergoing uniaxial ***,physical tests and simulations were conducted to determine the mechanical response(uniaxial compressive strength and macroscopic stiffness)of ore during uniaxial ***,the sensitivity of the mechanical response to the values of microscopic parameters was tested using a Plackett-Burman ***,the microscopic parameters with the greatest impact on the response were identified,and the range of parameters that met the target response was determined using a steepest ascent design;Second,a second-order model of the mechanical response was established using the sensitive parameters by combining a Box-Behnken design with response surface methodology to obtain the optimal BPM *** tests showed that the normal stiffness per unit area,critical shear stress,and bonded disk radius had significant effects on the uniaxial compressive strength(UCS)and macroscopic stiffness(MS).To verify the validity of the proposed calibration method,laboratory tests were *** consistency of the simulation results with experimental results indicated that response surface methodology with the Plackett-Burman design,steepest ascent design,and Box-Behnken design can be an effective method for calibrating the BPM of ores.

关键词： Bonded-particle model Discrete element method Calibration method Design of experiment Uniaxial compression test

Island biogeography theory and the habitat heterogeneity jointly explain global patterns of Rhododendron diversity

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Plant Diversity 2024年第5期46卷 565-574页

作者： Yanwei guan Yongru wu Zheng Cao Zhifeng wu Fangyuan Yu Haibin Yu Tiejun wang School of Geographical Sciences and Remote Sensing Guangzhou UniversityGuangzhou 510006China School of Life Sciences Guangzhou UniversityGuangzhou 510006China Department of Natural Resources Faculty of Geo-Information and Earth Observation(ITC)University of TwenteDrienerlolaan 5Enschede 7522 NBthe Netherlands

Mountain biodiversity is of great importance to biogeography and ***,it is unclear what ecological and evolutionary processes best explain the generation and maintenance of its high levels of species *** this study,we determined which of six common hypotheses(e.g.,climate hypotheses,habitat heterogeneity hypothesis and island biogeography theory)best explain global patterns of species diversity in *** found that Rhododendron diversity patterns were most strongly explained by proxies of island biogeography theory(i.e.,mountain area)and habitat heterogeneity(i.e.,elevation range).When we examined other relationships important to island biogeography theory,we found that the planimetric area and the volume of mountains were positively correlated with the Rhododendron diversity,whereas the‘mountains-to-mainland’distance was negatively correlated with Rhododendron diversity and shared *** findings demonstrate that Rhododendron diversity can be explained by island biogeography theory and habitat heterogeneity,and mountains can be regarded as islands which supported island biogeography theory.

关键词： Mountain biodiversity Rhododendron Island biogeography theory Habitat heterogeneity Biogeographical hypotheses Plant diversity