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Hydrodechlorination of trifluoro-trichloroethane to chlorotrifluoroethylene:Revealing the deactivation mechanism and regeneration strategy of Pd-Cu/AC catalyst

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Chinese Journal of Chemical Engineering 2024年第6期70卷 261-268页

作者： Song Tian Yicheng Chen Xiaoyu Wen Bingcheng Li jian Lu Zile Li feng feng Qingtao Wang Qunfeng Zhang Xiaonian Li State Key Laboratory Breeding Base of Green Chemistry Synthesis Technology Institute of Industrial Catalysis of Zhejiang University of TechnologyHangzhou 310014China State Key Laboratory of Fluorine&Nitrogen Chemicals Xi'an Modern Chemistry Research InstituteXi'an 710065China

Chlorotrifluoroethylene(CTFE)is a vital fluorinated olefinic monomer produced through the catalytic hydrodechlorination of trichlorotrifluoroethane(CFC-113),an eco-friendly ***,hydrodechlorination catalysts for olefin production often suffer from poor *** Pd/AC catalyst and Pd-Cu/AC catalyst prepared by co-impregnation method exhibited poor stability,Pd-Cu/AC catalyst with CFC-113 conversion dropping to around 37%after 50 h of hydrodechlorination ***-Emmett-Teller,transmission electron microscopy,X-ray photoelectron spectroscopy,and X-ray diffraction of fresh and deactivated Pd/AC catalysts indicate that the deactivation of Pd/AC catalysts is due to high-temperature agglomeration of *** analysis of fresh and deactivated Pd-Cu/AC catalysts using Brunauer-Emmett-Teller,transmission electron microscopy,and thermogravimetric analysis techniques revealed decreased dispersion of active sites,reduced surface area,catalyst aggregation deactivation,and a significant decrease in Cu ***,the results of NH3-TPD revealed that the acid sites of the catalyst increased significantly.X-ray diffraction spectra indicated the formation of new species,basic copper chloride(Cu_(2)(OH)_(3)Cl),during the *** the reaction progressed,these new species agglomerated,leading to a gradual loss of catalyst ***,the deactivated catalyst was successfully reactivated using a simple alkaline washing method.

关键词： CFC-113 Hydrodechlorination Chlorotrifluoroethylene Catalyst deactivation

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Jetting of a near-wall cavitation bubble induced by another tandem bubble

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Journal of Hydrodynamics 2024年第3期36卷 444-456页

作者： Hui Han Jing-zhu Wang jian-lin Huang Peng-bo bai Yong-gang Chen Yi-wei Wang Key Laboratory for Mechanics in Fluid Solid Coupling Systems Institute of MechanicsChinese Academy of SciencesBeijing100190China School of Engineering Science University of Chinese Academy of SciencesBeijing100049China Guangdong Aerospace Research Academy Guangzhou511458China School of Future Technology University of Chinese Academy of SciencesBeijing100049China jianghuai Advance Technology Center Hefei230088China

Double bubbles near a rigid wall surface collapse to produce a significant jet impact,with potential applications in surface cleaning and ultrasonic ***,the dynamic behaviors of near-wall bubbles remain *** this study,we investigate the jetting of a near-wall bubble induced by another tandem *** define two dimensionless standoff distances,γ_(1),γ_(2),to represent the distances from the center of the near-wall bubble to the rigid wall and the center of controlling bubble to the center of the near-wall bubble,*** observations reveal three distinct jetting regimes for the near-wall bubble:transferred jetting,double jetting,and directed *** further investigate the jetting mechanism,numerical simulations are conducted using the compressibleInterFoam solver in the open-source framework of OpenFOAM.A detailed analysis shows that the transferred jet flow is caused by the pinch-off resulting from the axial contraction velocity at the lower end of the near-wall bubble being greater than the vertical contraction velocity,leading to a maximum jet velocity of 682.58 m/*** the case of double jetting,intense stretching between the controlling bubble and the wall leads to a pinch-off and a double jetting with a maximum velocity of 1096.29 m/*** directed jet flow is caused by the downward movement of the high-pressure region generated by the premature collapse of the controlling bubble,with the maximum jet velocity reaching 444.62 m/s.

关键词： Jetting of near-wall bubble controlling bubble impact velocity

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Cytotoxic lignans from the roots and rhizomes of Diphylleia sinensis,a China's endemic plant species

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Chinese Journal of Natural Medicines 2024年第9期22卷 831-841页

作者： SUN Yanjun ZHAO Chen bai Hongyun LI Meng WANG Junmin HAO Zhiyou feng Weisheng Co-construction Collaborative Innovation Center for Chinese Medicine and Respiratory Diseases by Henan&Education Ministry of China Henan University of Chinese MedicineZhengzhou 450046China Engineering and Technology Center for Chinese Medicine Development of Henan Province Zhengzhou 450046China School of Pharmacy Henan University of Chinese MedicineZhengzhou 450046China

Eight novel arylnaphthalide lactone lignans, designated as diphylignan A-H(1-8), and a new dibenzyltyrolactone lignan, designated as diphylignan I(9), were isolated from the roots and rhizomes of Diphylleia sinensis, along with two additional novel natural products(11 and 14) and four known metabolites(10, 12, 13, 15). The structural and stereochemical characterization of these compounds was accomplished using NMR spectroscopy and electronic circular dichroism(ECD) analysis. The cytotoxic activities of all isolated compounds were assessed against A-549 and SMMC-7721 cell lines. Notably, compound 2 demonstrated the most significant cytotoxicity, with IC_(50) values of 10.27 and 11.58 μmol·L^(-1) against A-549 and SMMC-7721 cell lines, respectively, exhibiting greater potency than the positive control, cisplatin.

关键词： Diphylleia sinensis Dibenzyltyrolactone Arylnaphthalide Cytotoxic

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Water modeling on fluid flow and mixing phenomena in a BOF steelmaking converter

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Journal of Iron and Steel Research International 2024年第3期31卷 595-607页

作者： Xin-yu Cai Hao-jian Duan Ding-han Li Anjun Xu Li-feng Zhang School of Metallurgical and Ecological Engineering University of Science and Technology Beijing(USTB)Beijing 100083China School of Mechanical and Materials Engineering North China University of TechnologyBeijing 100144China

A 1∶8 physical water model was constructed to investigate the fluid flow and mixing phenomena in the basic oxygen furnace(BOF)*** particle image velocimetry was employed to measure the velocity distribution of the bath and the high-speed camera was applied to capture the cavity shape in the combined blowing BOF *** mixing time for varied operating conditions was measured by the stimulus-response *** cavity depth increased with the decrease in the lance height and the increase in the top gas flow rate while the bottom blowing gas had little influence on the cavity *** minimum cavity depth was obtained under the condition of a 69.8 m^(3)/h top gas flow rate,a 287.5 mm lance height and a 0.93 m^(3)/h bottom blowing gas flow rate,which was 161.2 *** mixing time decreased as the lance height decreased and the top blowing gas flow rate *** mixing time was first decreased and then increased with the increase in the bottom gas flow *** the condition of 69.8 m^(3)/h gas flow rate of top blowing,the 287.5 mm lance height and the 0.93 m^(3)/h gas flow rate of bottom blowing,the mixing time in the converter was 48.65 *** empirical formula between the stirring power and the mixing time in the converter was calculated.

关键词： Water model Fluid flow Particle image velocimetry Mixing time BOF converter

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Knockout of a rice K5.2 gene increases Ca accumulation in the grain

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Journal of Integrative Plant Biology 2024年第2期66卷 252-264页

作者： Peitong Wang Naoki Yamaji Namiki Mitani-Ueno Jun Ge jian feng Ma National Key Laboratory of Crop Genetics&Germplasm Enhancement and Utilization College of Resources and Environmental SciencesNanjing Agricultural UniversityNanjing 210095China Institute of Plant Science and Resources Okayama UniversityKurashiki 710-0046Japan

Rice is a staple food for half of the world’s population,but it is a poor dietary source of calcium(Ca)due to the low *** is an important issue to boost Ca concentration in this grain to improve Ca deficiency risk,but the mechanisms underlying Ca accumulation are poorly ***,we obtained a rice(Oryza sativa)mutant with high shoot Ca *** mutant exhibited 26%-53% higher Ca in shoots than did wild-type rice(WT)at different Ca *** concentration in the xylem sap was 36% higher in the mutant than in the *** was no difference in agronomic traits between the WT and mutant,but the mutant showed 25% higher Ca in the polished grain compared with the ***-based cloning combined with a complementation test revealed that the mutant phenotype was caused by an 18-bp deletion of a gene,OsK5.2,belonging to the Shaker-like K+channel ***5.2 was highly expressed in the mature region of the roots and its expression in the roots was not affected by Ca levels,but upregulated by low *** showed that OsK5.2 was mainly expressed in the pericycle of the *** together,our results revealed a novel role for OsK5.2 in Ca translocation in rice,and will be a good target for Ca biofortification in rice.

关键词： accumulation biofortification calcium OsK5.2 pericycle rice translocation

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Cu-catalyzed regioselective diborylation of 1,3-enynes for the efficient synthesis of 1,4-diborylated allenes

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Chinese Chemical Letters 2024年第5期35卷 141-144页

作者： Wujun jian Mong-feng Chiou Yajun Li Hongli Bao Song Yang National Key Laboratory of Green Pesticide Key Laboratory of Green Pesticide and Agricultural BioengineeringMinistry of EducationCenter for R&D of Fine Chemicals of Guizhou UniversityGuiyang 550025China Strait Institute of Flexible Electronics(SIFE Future Technologies)Fujian Normal UniversityFuzhou 350117China Key Laboratory of Coal to Ethylene Glycol and Its Related Technology State Key Laboratory of Structural ChemistryFujian Institute of Research on the Structure of MatterUniversity of Chinese Academy of SciencesFuzhou 350002China

Borylation of 1,3-enynes with bis(boronate)compounds often ends up with the formation of hydroborylated products,leaving the diborylation of 1,3-enynes for the formation of 1,4-diborylated allenes to be ***,a copper-catalyzed chemo-,regio-,and stereo-selective diborylation of 1,3-enynes for the efficient construction of 1,4-diborylated allenes under base-free conditions was reported.A wide range of 1,3-enynes bearing various functional groups can participant in the reaction and afforded the corresponding 1,4-diborylated allenes in good to excellent yields,which was enabled by the protocol of Bpin to BF3K *** borylcopper species was supposed to selectively attack the C-C triple bond of the 1,3-enynes.

关键词： Copper catalysis Regioselective 1,3-Enynes Borylation Allenes

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Suppression of low-frequency ultrasound broadband vibration using star-shaped single-phase metamaterials

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Defence Technology（防务技术） 2024年第4期34卷 217-224页

作者： Rui Zhao jian Zheng Jin Guo Yunbo Shi Hengzhen feng Jun Tang Jun Liu Science and Technology on Electronic Test&Measurement Laboratory North University of ChinaTaiyuan 030051ShanxiChina School of Mechatronical Engineering Beijing Institute of TechnologyBeijing 100081China

In order to suppress the low-frequency ultrasound vibration in the broadband range of 20 k Hz—100 k Hz,this paper proposes and discusses an acoustic metamaterial with low-frequency ultrasound vibration attenuation properties,which is configured by hybrid arc and sharp-angle convergent star-shaped *** effect of the dispersion relation and the bandgap characteristic for the scatterers in star-shaped are simulated and *** target bandgap width is extended by optimizing the geometry parameters of arc and sharp-angle convergent *** proposed metamaterial configured by optimized hybrid lattices exhibits remarkable broad bandgap characteristics by bandgap complementarity,and the simulation results verify a 99%vibration attenuation amplitude can be obtained in the frequency of20 k Hz—100 k *** the fabrication of the proposed hybrid configurational star-shaped metamaterial by 3D printing technique,the transmission loss experiments are performed,and the experimental results indicate that the fabricated metamaterial has the characteristics of broadband vibration attenuation and an amplitude greater than 85%attenuation for the target *** results demonstrate that the hybrid configurational star-shaped metamaterials can effectively widen the bandgap and realize high efficiency attenuation,which has capability for the vibration attenuation in the application of highprecise equipment.

关键词： Star-shaped metamaterials Broadband Vibration attenuation Low-frequency ultrasound vibration Transmission loss

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Hemorrhagic transformation in patients with large-artery atherosclerotic stroke is associated with the gut microbiota and lipopolysaccharide

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Neural Regeneration Research 2024年第7期19卷 1532-1540页

作者： Qin Huang Minping Wei Xianjing feng Yunfang Luo Yunhai Liu jian Xia Department of Neurology Xiangya HospitalCentral South UniversityChangshaHunan ProvinceChina Department of Neurology Peking University People’s HospitalBeijingChina Clinical Research Center for Cerebrovascular Disease of Hunan Province Central South UniversityChangshaHunan ProvinceChina National Clinical Research Center for Geriatric Disorders Xiangya HospitalCentral South UniversityChangshaHunan ProvinceChina

Hemorrhagic transformation is a major complication of large-artery atheroscle rotic stroke(a major ischemic stro ke subtype)that wo rsens outcomes and increases *** of the gut microbiota is an important feature of stroke,and some specific bacteria and bacterial metabolites may contribute to hemorrhagic transformation *** aimed to investigate the relationship between the gut microbiota and hemorrhagic transformation in largearte ry atheroscle rotic stro *** observational retrospective study was *** May 2020 to September 2021,blood and fecal samples were obtained upon admission from 32 patients with first-ever acute ischemic stroke and not undergoing intravenous thrombolysis or endovascular thrombectomy,as well as 16 healthy *** with stro ke who developed hemorrhagic transfo rmation(n=15)were compared to those who did not develop hemorrhagic transformation(n=17)and with healthy *** gut microbiota was assessed through 16S ribosomal ribonucleic acid *** also examined key components of the lipopolysaccharide pathway:lipopolysaccharide,lipopolysaccharide-binding protein,and soluble *** observed that bacterial diversity was decreased in both the hemorrhagic transformation and non-hemorrhagic transfo rmation group compared with the healthy *** patients with ischemic stro ke who developed hemorrhagic transfo rmation exhibited altered gut micro biota composition,in particular an increase in the relative abundance and dive rsity of members belonging to the Enterobacteriaceae *** lipopolysaccharide and lipopolysaccharide-binding protein levels were higher in the hemorrhagic transformation group compared with the non-hemorrhagic transfo rmation ***,lipopolysaccharide-binding protein,and soluble CD14 concentrations were associated with increased abundance of Enterobacte ***,the role of the gut microbiota in hemorrhagic transformation was evaluated using

关键词： gut microbiota hemorrhagic transformation inflammation lipopolysaccharide stroke

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Trend of Storm Surge Induced by Typical Landfall Super Typhoons During 1975–2021 in the Eastern China Sea

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Journal of Ocean University of China 2024年第2期23卷 277-286页

作者： LUO feng WANG Yi TAO Aifeng SHI jian WANG Yongzhi ZHANG Chi College of Harbour Coastal and Offshore EngineeringHohai UniversityNanjing 210098China Nantong Ocean and Coastal Engineering Research Institute Hohai UniversityNantong 226000China Key Laboratory of Ministry of Education for Coastal Disaster and Protection Hohai UniversityNanjing 210098China College of Meteorology and Oceanography National University of Defense TechnologyChangsha 410073China The First Institute of Oceanography MNRQingdao 266061China

Climate change affects the activity of global and regional tropical cyclones(TCs).Among all TCs,typical super typhoons(STYs)are particularly devastating because they maintain their intensity when landing on the coast and thus cause casualties,economic losses,and environmental *** a 3D tidal model,we reconstructed the typhoon(TY)wind field to simulate the storm surge induced by typical *** TY activity was then analyzed using historical *** showed a downtrend of varying degrees in the annual frequency of STYs and TCs in the Western North Pacific(WNP)Basin,with a significant trend change observed for TCs from 1949 to 2021.A large difference in the interannual change in frequency was found between STYs and TCs in the WNP and Eastern China Sea(ECS).Along the coast of EC,the frequency of landfall TCs showed a weak downtrend,and the typical STYs showed reverse micro growth with peak activity in ***,Fujian,and Taiwan were highly vulnerable to the frontal hits of typical *** by climate change,the average lifetime maximum intensity(LMI)locations and landfall locations of typical STYs in the ECS basin showed a significant poleward migration *** addition,the annual average LMI and accumulated cyclone energy showed an uptrend,indicating the increasing severity of the disaster *** by the typical STY activity in the ECS,the maximum storm surge area also showed poleward migration,and the coast of North China faced potential growth in high storm surge risks.

关键词： storm surge super typhoons tropical cyclones eastern China Sea poleward migration

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The Analysis of the Correlation between SPT and CPT Based on CNN-GA and Liquefaction Discrimination Research

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Computer Modeling in Engineering & Sciences 2024年第2期138卷 1159-1182页

作者： Ruihan bai feng Shen Zihao Zhao Zhiping Zhang Qisi Yu Key Laboratory of the Ministry of Education for Geomechanics and Embankment Engineering College of Civil and Transportation EngineeringHohai UniversityNanjing210098China School of Civil Engineering Suzhou University of Science and TechnologySuzhou215011China School of Civil Engineering Shenyang Jianzhu UniversityShenyang110168China College of Civil Engineering Tongji UniversityShanghai200092China

The objective of this study is to investigate themethods for soil liquefaction discrimination. Typically, predicting soilliquefaction potential involves conducting the standard penetration test (SPT), which requires field testing and canbe time-consuming and labor-intensive. In contrast, the cone penetration test (CPT) provides a more convenientmethod and offers detailed and continuous information about soil layers. In this study, the feature matrix based onCPT data is proposed to predict the standard penetration test blow count N. The featurematrix comprises the CPTcharacteristic parameters at specific depths, such as tip resistance qc, sleeve resistance f s, and depth H. To fuse thefeatures on the matrix, the convolutional neural network (CNN) is employed for feature extraction. Additionally,Genetic Algorithm (GA) is utilized to obtain the best combination of convolutional kernels and the number ofneurons. The study evaluated the robustness of the proposed model using multiple engineering field data *** demonstrated that the proposed model outperformed conventional methods in predicting N values forvarious soil categories, including sandy silt, silty sand, and clayey silt. Finally, the proposed model was employedfor liquefaction discrimination. The liquefaction discrimination based on the predicted N values was comparedwith the measured N values, and the results showed that the discrimination results were in 75% agreement. Thestudy has important practical application value for foundation liquefaction engineering. Also, the novel methodadopted in this research provides new ideas and methods for research in related fields, which is of great academicsignificance.

关键词： CNN liquefaction discrimination SPT CPT

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