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Enhancing photoresponsiveness of metal-organic polyhedra by modifying microenvironment

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Nano Research 2024年第6期17卷 5712-5717页

作者： Long Zheng Peng Tan Qian Song sheng-Tao wang Min Li Xiao-Qin Liu lin-Bing Sun State Key Laboratory of Materials-Oriented Chemical Engineering Jiangsu National Synergetic Innovation Center for Advanced Materials(SICAM)College of Chemical EngineeringNanjing Tech UniversityNanjing 211816China

Photoresponsiveness of materials is critical to their tunability and efficiency in terminal *** metal-organic polyhedra(PMOPs)feature intrinsic pores and remote controllability,but aggregation of PMOPs in solid state hampers their photoresponsiveness ***,we report the construction of a new PMOP(Cu_(24)(C_(16)H_(12)N_(2)O_(4))_(12)(C_(18)H_(22)O_(5))12,denoted as MOP-PR-LA),where long alkyl(LA)chains act as the intermolecular poles,propping against adjacent PMOP molecules to create individual microenvironment benefiting the isomerization of photoresponsive(PR)*** ultraviolet(UV)-and visible-light irradiation,MOP-PR-LA is much easier to isomerize than the counterpart MOP-PR without *** propylene adsorption,MOP-PR has a low change of adsorption capacity(9.9%),while that of MOP-PR-LA reaches 58.6%.Density functional theory calculations revealed that PR in the cis state has a negative effect on adsorption,while the trans state of PR favors *** work might open an avenue for the construction of photoresponsive materials with high responsiveness and controllability.

关键词： photoresponsive adsorption metal-organic polyhedra azobenzene long alkyl chains propylene capture

Multilevel Micro Structures of the Clam Make the Sealing Even Tighter

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Journal of Bionic Engineering 2024年第3期21卷 1442-1452页

作者： Daobing Chen Xiaolong Zhang Junqiu Zhang Zhiwu Han Ruteng wang Zhen lin Yifeng Lei Longjian Xue sheng Liu The Institute of Technological Science Wuhan UniversityWuhan430072China School of Power and Mechanical Engineering Wuhan UniversityWuhan430072China The Key Laboratory of Bionic Engineering(Ministry of Education) Jilin UniversityChangchun130022China Institute of Structured and Architected Materials Liaoning Academy of MaterialsShenyang110167China

Excellent fluid sealing performance is crucial to ensuring the safety of important equipment,especially in aerospace field,such as space capsule and fuel *** frequently opening and closing of the sealing devices is particularly *** by this background,clams(Mactra chinensis)which can open and close their double shells with superior sealing performance,are studied in this ***,we show that the clam’s sealing ability is the result of its unique multilevel intermeshing microstructures,including hinge teeth and *** microstructures,which resemble gear teeth,engage with each other when the shell closes,forming a tight structure that prevents the infiltration of water from the ***,the presence of micron blocks prevents the penetration of finer *** simulation results of the bionic end seal components show that the multilevel microstructure has a superior sealing *** research is expected to be applied to undersea vehicles that require frequent door opening and closing.

关键词： Multilevel micro structures Opening and closing components Clam Sealing Bionic

Universal and efficient hybrid modeling and direct slicing method for additive manufacturing processes

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Advances in Manufacturing 2024年第2期12卷 300-316页

作者： Sen-lin wang Li-Chao Zhang Chao Cai Ming-Kai Tang Si Chen Jiang Huang Yu-sheng Shi State Key Laboratory of Materials Processing and Die and Mould Technology Huazhong University of Science and TechnologyWuhan430074People’s Republic of China School of Machinery and Automation Wuhan University of Science and TechnologyWuhan430081People’s Republic of China

Model design and slicing contour generation in additive manufacturing(AM)data processing face challenges in terms of efficiency and scalability when stereolithography files generated by complex functionally graded structures have millions of *** paper proposes a hybrid modeling and direct slicing method for AM to efficiently construct and handle complex three-dimensional(3D)*** 3D solids,including conformal multigradient structures,were uniformly described using a small amount of data via signed distance *** hybrid representations were quickly discretized into numerous disordered directed lines using an improved marching squares *** establishing a directional HashMap to construct the topological relationship between lines,a connecting algorithm with linear time complexity is proposed to generate slicing contours for *** method replaces the mesh reconstruction and Boolean operation stages and can efficiently construct complex conformal gradient models of arbitrary topologies through hybrid ***,the time and memory consumption of direct slicing are much lower than those of previous methods when handling hybrid models with hundreds of millions of faces after mesh reconstruction.

关键词： Additive manufacturing(AM) Hybrid modeling Direct slicing Signed distance field

Hepatic steatosis with mass effect:A case report

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World Journal of Clinical Cases 2022年第30期10卷 11066-11073页

作者： Na Hu Shi-Jun Su Jin-Ye Li Hui Zhao Shan-Feng Liu lin-sheng wang Ruo-Zhen Gong Chuan-Ting Li Department of Radiology Shandong Provincial ENT HospitalShandong UniversityJinan 250023Shandong ProvinceChina Department of Radiology The Fifth People's Hospital of JinanJinan 250022Shandong ProvinceChina Innovation Studio Shandong Provincial ENT HospitalShandong UniversityJinan 250023Shandong ProvinceChina Department of Radiology Shandong Provincial HospitalShandong UniversityJinan 250021Shandong ProvinceChina

BACKGROUND Hepatic steatosis is a common radiologic *** imaging inklings are the absence of a mass effect,and there is currently no report of hepatic steatosis with mass *** SUMMARY A 23-year-old female was admitted due to a liver mass for half a *** obvious abnormalities were found in physical and laboratory ***,computed tomography,and magnetic resonance imaging showed a huge mass between the liver and stomach with a significant mass effect,and the caudate lobe and left lobe of the liver were *** signal on T2-and T1-weighted fat-saturated images of the mass was significantly reduced,and the enhanced scan showed inhomogeneous *** and pathological findings indicated the diagnosis of hepatic *** operation and re-review of the patient’s images showed that the lesion was supplied by the branch of the hepatic *** signal on T1-weighted out-of-phase images of the lesion was lower than on in-phase images,and there was no black rim cancellation artifact around the hepatic steatosis area on T1-weighted out-of-phase *** dynamic enhancement pattern of the lesion was similar to that of the adjacent normal liver *** above characteristics suggested that the lesion was hepatic ***,in this case,the lesion showed exogenous growth and was mass-like,with an obvious mass effect,which has not been reported *** Hepatic steatosis could grow exogenously and has an obvious mass *** needs to be distinguished from fat-rich *** T1-weighted in-and out-of-phase images and dynamic enhanced scanning are valuable for differential diagnosis of this lesion.

关键词： Hepatic steatosis Computed tomography Magnetic resonance imaging In-phase and out-of-phase imaging Case report

Catalytically generated noncovalent ammonium dienolate:a versatile platform for the development of organocatalytic asymmetric cascade reactions

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Science China Chemistry 2024年第8期67卷 2524-2546页

作者： Jun-Bing lin Dong-sheng Ji Peng-Fei Xu State Key Laboratory of Applied Organic Chemistry College of Chemistry and Chemical EngineeringLanzhou UniversityLanzhou 730000China Shaanxi Key Laboratory of Chemical Reaction Engineering College of Chemistry and Chemical EngineeringYan’an UniversityYan’an 716000China

Organocatalytic cascade reactions represent a powerful strategy for the rapid construction of complex chiral molecules with multiple stereocenters from simple substrates under mild conditions. The intriguing structural feature and diverse reactivity of catalytically generated dienolate species render them competent and versatile intermediates for the development of practical and valuable cascade reactions. Over the past years, a plethora of innovative and pioneering noncovalent ammonium dienolatemediated cascade reactions have been designed and implemented under the catalysis of chiral organocatalysts, making dienolate activation a general, robust, and complementary method for the functionalization of unsaturated carbonyl compounds and related substances. This review illustrates the recent advances in organocatalytic noncovalent ammonium dienolate-mediated cascade reactions(mainly from 2010 to 2023), including the cascade transformations of ammonium dienolates directly generated from unsaturated ketone/aldehyde, ester/lactone/azlactone, amide/lactam/pyrazolone/oxindole, and alkylidene nitrile compounds. The contents are arranged based on the reaction types of the ammonium dienolates, with an emphasis on cascade 2,5-, 3,5-, and 4,5-difunctionalizations of these intermediates. Furthermore, other cascade reactions involving the 1,3-, 2,3-, and even more complex 3,4,5-reactivities of ammonium dienolates were also discussed. The reaction pathway, reaction stereoinduction, and synthetic applications of the ammonium dienolate-mediated cascade reactions were highlighted throughout the article. As a stimulating and ever-growing research area, the organocatalytic noncovalent ammonium dienolate-mediated cascade reactions are expected to continue demonstrating their magic power for constructing chiral targets in the future and further expanding the boundaries of asymmetric catalysis.

关键词： organocatalysis asymmetric catalysis ammonium dienolate cascade reaction difunctionalization

Experimental,Numerical,and Analytical Studies on the Bending of Mechanically lined Pipe

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China Ocean Engineering 2024年第2期38卷 221-232页

作者： WEI Wen-bin YUAN lin ZHOU Jia-sheng LIU Zheng State Key Laboratory of Hydraulic Engineering Simulation and Safety Tianjin UniversityTianjin 300072China School of Civil Engineering Tianjin UniversityTianjin 300072China School of Mechanical Engineering Tianjin UniversityTianjin 300072China

Mechanically lined pipe(MLP)is often used for offshore oil and gas transport because of its low cost and corrosion *** installation and operation,the pipe may undergo severe bending deformation,which causes the liner to separate from the outer pipe and buckles,affecting the stability of the whole *** this paper,the buckling response of MLP subjected to bending is investigated to clarify its bending characteristics by employing both experiments,numerical simulation,as theoretical *** types of MLPs were manufactured with GB 45 carbon steel(SLP)and Al 6061(ALP)used as the outer pipe material,*** hydraulic expansion and bending experiments of small-scale MLPs are *** addition to the ovalized shape of the cross-section for the SLP specimens,the copper liner was found to wrinkle on the compressive *** contrast,the liner of ALP remains intact without developing any wrinkling and collapse *** addition,a dedicated numerical framework and theoretical models were also *** was found both the manufacturing and bending responses of the MLP can be well reproduced,and the predicted maximum moment and critical curvatures are in good agreement with the experimental results.

关键词： lined pipe bending nonlinear ring theory buckling plasticity

In situ tracking of the lithiation and sodiation process of disodium terephthalate as anodes for rechargeable batteries by Raman spectroscopy

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Nano Research 2024年第1期17卷 245-252页

作者： Xiu-Mei lin Chong Han Xin-Tao Yang Jia-sheng lin Wei-Qiang Yang Hong-Xu Guo Yao-Hui wang Jin-Chao Dong Jian-Feng Li Department of Chemistry and Environment Science Fujian Province University Key Laboratory of Analytical ScienceMinnan Normal UniversityZhangzhou 363000China College of Energy College of Chemistry and Chemical EngineeringCollege of MaterialsState Key Laboratory of Physical Chemistry of Solid SurfacesiChEMXiamen UniversityXiamen 361005China Institute of Optical and Electronic Technology China Jiliang UniversityHangzhou 310018China

Organic compounds represent an appealing group of electrode materials for rechargeable batteries due to their merits of biomass,sustainability,environmental friendliness,and *** terephthalate(Na_(2)C_(8)H_(4)O_(4),Na_(2)TP),an organic salt with a theoretical capacity of 255 mAh·g^(-1),is electroactive towards both lithium and ***,its electrochemical energy storage(EES)process has not been directly observed via in situ characterization techniques and the underlying mechanisms are still under ***,in situ Raman spectroscopy was employed to track the de/lithiation and de/sodiation processes of *** appearance and then disappearance of the–COOLi Raman band at 1625 cm^(-1) during the de/lithiation,and the increase and then decrease of the–COONa Raman band at 1615 cm^(-1) during the de/sodiation processes of Na2TP elucidate the one-step with the 2Li+or 2Na+transfer *** also found that the inferior cycling stability of Na2TP as an anode for sodium-ion batteries(SIBs)than lithium-ion batteries(LIBs)could be due to the larger ion radium of Na+than Li+,which results in larger steric resistance and polarization during *** Na2TP,therefore,shows greater changes in spectra during de/sodiation than de/*** expect that our findings could provide a reference for the rational design of organic compounds for EES.

关键词： disodium terephthalate(Na_(2)C_(8)H_(4)O_(4) Na2TP) in situ Raman spectroscopy de/lithiation de/sodiation mechanisms

Carbon capture in power sector of China towards carbon neutrality and its comparison to renewable power

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Fundamental Research 2024年第4期4卷 916-925页

作者： sheng Li lin Gao Song He Dongtai Yang Chaowei wang Yawen Zheng School of mechanical engineering Beijing Institute of TechnologyBejing 100081China Laboratory of Integrated Energy System and Renewable Eery Institute of Engineering ThemophysicsChinese Academyof SciencesBejing0010China

CO_(2)capture from coal power plants is an important and necessary solution to realizing carbon neutrality in China,but ccs demonstration deployment in power sector is far behind ***,the reduction potential of energy consumption and cost for CcS and its competitiveness to renewable powers are very important to make roadmaps and policies toward carbon *** the popular recognition that capturing CO_(2)from flue gases is technically and commercially mature,this paper notes that it has been proved to be technically feasible but far beyond technology maturity and high energy penalty leads to its immaturity and therefore causes high ***,the potential energy penalty reduction of capture is investigated thermodynamically,and future CO_(2)avoidance cost is predicted and compared to renewable power(solar PV and onshore wind power).Results show that energy penalty for CO_(2)capture can be reduced by 48%-57%.When installation capacity reaches a similar scale to that of solar PV in China(250 GW),CO_(2)capture cost in coal power plants can be reduced from the current 28-40 USs/ton to 10-20 USs/ton,and efficiency upgrade contributes to 67%-75%in cost reduction for high coal price *** China,CO_(2)capture in coal power plants can be cost competitive with solar PV and onshore wind *** it is worth noting that the importance and share of CCS role in CO_(2)emission reduction is decreasing since renewable power is already well deployed and there is still a lack of large-scale CO_(2)capture demonstrations in *** capture technologies with low energy penalties need to be developed to promote *** in this work can provide informative references for making roadmaps and policies regarding CO_(2)emission reductions that contribute towards carbon neutrality.

关键词： Carbon capture and storage Carbon neutrality Energy consumption Fluegas Renewable energy

Method for rapid warning and activity concentration estimates in online waterγ-spectrometry systems

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Nuclear Science and Techniques 2024年第3期35卷 1-12页

作者： Meng wang Yi Gu Mao-lin Xiong Liang-Quan Ge Qing-Xian Zhang Guo-Qiang Zeng Heng Lu sheng-Liang Guo College of Nuclear Technology and Automation Engineering Chengdu University of TechnologyChengdu 610059China Applied Nuclear Technology in Geosciences Key Laboratory of Sichuan Province (Chengdu University of Technology)Chengdu 610059China Chengdu New Ray Technology Co.Ltd Chengdu 610052China

Onlineγ-spectrometry systems for inland waters,most of which extract samples in situ and in real time,are able to produce reliable activity concentration measurements for waterborne radionuclides only when they are distributed relatively uniformly and enter into a steady-state diffusion regime in the measurement *** protect residents’health and ensure the safety of the living environment,better timeliness is required for this measurement *** address this issue,this study established a mathematical model of the online waterγ-spectrometry system so that rapid warning and activity estimates can be obtained for water under non-steady-state(NSS)*** addition,the detection efficiency of the detector for radionuclides during the NSS diffusion process was determined by applying the computational fluid dynamics technique in conjunction with Monte Carlo *** this basis,a method was developed that allowed the online waterγ-spectrometry system to provide rapid warning and activity concentration estimates for radionuclides in *** analysis of the NSS-mode measurements of^(40)K radioactive solutions with different activity concentrations determined the optimum warning threshold and measurement time for producing accurate activity concentration estimates for *** experimental results show that the proposed NSS measurement method is able to give warning and yield accurate activity concentration estimates for radionuclides 55.42 and 69.42 min after the entry of a 10 Bq/L^(40)K radioactive solution into the measurement chamber,*** times are much shorter than the 90 min required by the conventional measurement ***,the NSS measurement method allows the measurement system to give rapid(within approximately 15 min)warning when the activity concentrations of some radionuclides reach their respective limits stipulated in the Guidelines for Drinking-water Quality of the WHO,suggesting that this method con

关键词： Water radioactivity monitoring Dynamic detection efficiency Rapid warning Activity estimation