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Metal-organic frameworks on 3D interconnected macroporous sponge foams for large-scale water decontamination:A mini review

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Chinese Chemical Letters 2024年第5期35卷 77-84页

作者： Xiao-Hong Yi chong-Chen Wang Beijing Key Laboratory of Functional Materials for Building Structure and Environment Remediation School of Environment and Energy EngineeringBeijing University of Civil Engineering and ArchitectureBeijing 100044China

Water pollution caused by global population growth,urban expansion and industrialization development is one of the urgent issues that need to be addressed in the 21st *** to now,it was challenging for metal-organic frameworks(MOFs)to be used in the actual water treatment due to that the powder MOFs suffered from difficult reuse,poor water stability and easy *** is an effective strategy to immobilize MOFs powder onto porous sponge foam carriers for accomplishing large flux,facile recycling,easy processing water treatment *** this review article,the fabrication approaches and applications of different MOFs/sponge composites were highlighted,in which the fluorescence detection of pollutants,adsorption and separation of pollutants,catalytic reduction and oxidation of pollutants were ***,the future challenges and opportunities of MOF/sponge for water treatment are proposed,aiming to provide in-depth guidance for the future design and manufacture of the immobilized MOFs onto sponge foams.

关键词： Metal-organic frameworks Sponge foam Water decontamination Adsorption Catalysis

Key Parameters Analysis and Regulation of Singlet Oxygen Quenching Rate of Carotenoids

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Chinese Journal of Structural Chemistry 2020年第7期39卷 1226-1234页

作者： ZHAO Kai JIANG Wei MENG chong Education Academy Beijing Sport UniversityBeijing 100084China School of Environment Beijing Normal UniversityBeijing 100875China

28 kinds of carotenoids are studied to reveal the key parameters and regulation on the singlet oxygen quenching ***,the quantum chemistry parameters of carotenoids calculated by Gaussian software combined with substitution parameters were used to construct the quantitative structure-activity relationship model(QSAR)of the singlet oxygen quenching rate of *** key parameters affecting the antioxidant activity of carotenoids are revealed,and the data predicted via the QSAR model were provided for subsequent ***,a three-dimensional(3D)pharmacophore model was used to regulate and modify the antioxidant activity of *** correlation coefficients of the modeling group(R2)and verification group(Rpre2)of the established QSAR model were 0.945 and 0.916,respectively,which can be used for the analysis of antioxidant activity of carotenoids;the antioxidant activity of carotenoids can be significantly regulated by the number of conjugated C=C bonds,the energy difference between frontier molecular orbitals and the partial Mulliken charge in C1 and theπ···π*excitation energy E(s);the antioxidant activity of carotenoids can be effectively regulated by the hydrogen bond acceptor pharmacophores on both sides of the conjugated C=C bonds and the hydrophobic groups on the conjugated C=C bond;the hydrophobic substituents attached to conjugated C=C bonds can effectively improve the singlet oxygen quenching rate of carotenoids.

关键词： carotenoids singlet oxygen quenching quantitative structure-activity relationship model 3D pharmacophore model parameters analysis

Salvianolic acid B promotes the invasion and migration of H_(2)O_(2)-induced HTR-8/Svneo trophoblast cells by upregulating matrix metalloproteinase-9 via the phosphatidylinositol-4,5-bisphosphate 3-kinase/protein kinase B pathway

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Journal of Traditional Chinese Medicine 2023年第3期43卷 457-465页

作者： ZHAO Zhiqiang ZHANG chong ZHU Yunxia Department of Gynecology and Obstetrics Beijing You'an Hospital of Capital Medical UniversityBeijing 100069China

OBJECTIVE:To elucidate the regulatory effects of salvianolic acid B(Sal B)on trophoblast cells in preeclampsia(PE).METHODS:3-(4,5-dimethylthiazol-2-yl)-2,5 diphenyltetrazolium bromide(MTT)assays were used to detect the viability of human extravillous trophoblast HTR-8/Svneo cells induced by H_(2)O_(2)following treatment with different concentrations of Sal *** levels of oxidative stressrelated molecules,including superoxide dismutase,glutathione-Px and malondialdehyde were detected using corresponding *** apoptosis was detected using a Terminal deoxynucleotidyl transferase(Td T)d UTP NickEnd Labeling(TUNEL)assay,and the expression of apoptosis-related proteins was detected using western blot *** the present study,wound healing and Transwell assays were performed to measure the levels of cell invasion and *** blot analysis was also used to detect the expression levels of epithelialmesenchymal transition-related *** mechanisms underlying Sal B were further investigated using reverse transcription-quantitative real-time polymerase chain reaction(RT-q PCR)and western blot analysis,to determine the expression levels of matrix metallopeptidase 9(MMP-9)and phosphatidylinositol-4,5-bisphosphate 3-kinase(PI3K)/protein kinase B(Akt).RESULTS:Sal B increased the activity of HTR-8/Svneo cells,inhibited oxidative damage and promoted the invasion and migration of trophoblast cells induced by H_(2)O_(2).Furthermore,the expression levels of MMP-9 and members of the PI3K/Akt signaling pathway were significantly *** pathway agonist,LY294002,and MMP-9 inhibitor,GM6001,reversed the effects of Sal B on H_(2)O_(2)-induced ***:Sal B promoted the invasion and migration of H_(2)O_(2)-induced HTR-8/Svneo trophoblast cells by upregulating MMP-9 via the PI3K/Akt signaling pathway.

关键词： sennosides matrix metallopeptidase 9 phosphatidylinositol 3-kinase protein kinases HTR-8/Svneo trophoblast cell invasion migration

Zero Refractive Index Properties of Two-Dimensional Photonic Crystals with Dirac Cones

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Chinese Physics Letters 2019年第3期36卷 37-40页

作者： Guo-Guo Wei chong Miao Hao-chong Huang Hua Gao School of Science China University of Geosciences

The zero refractive index properties of two-dimensional photonic crystals(PCs) are studied theoretically. Three necessary conditions for PCs to mimic the zero index materials(ZIMs) are obtained. In addition, through a comparative study of the properties for two representative PC structures with different types of Dirac cones, we find that the PC with a Dirac-like cone which meets the three necessary conditions does not behave as a ZIM in some cases. Further analysis shows that its non-zero index properties originate from the flat dispersion *** findings clarify the fundamental physical issue of which type of Dirac cone PC can mimic a real ZIM.

关键词： Zero Refractive Index Properties Crystals

Microstructure and Properties of In Situ Si and Fe-rich Particles Reinforced Al Matrix Composites Assisted with Ultrasonic Vibration

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Acta Metallurgica Sinica(English Letters) 2014年第5期27卷 862-868页

作者： Shulin Lü Shusen Wu chong Lin Ping An State Key Laboratory of Materials Processing and Die & Mould Technology Huazhong University of Science and Technology

In this research, the in situ Si and Fe-rich particles reinforced Al matrix composites were fabricated by rheocasting （RC） process assisted with ultrasonic vibration （USV）. After USV treatment, the polygonal primary Si crystals were refined into particles with average diameter of about 15-23 μm, and the fraction of primary Si declined to about 5.4-6.5 vol%. The coarse plate-like δ-Al4（Fe,Mn）Si2 phase was transformed into fine particles with average diameter of about 17-20 μm, and the fraction of particle-like Fe-bearing particles is about 3.6-5.3 vol%. The ultimate tensile strength of the RC composites increases with the increase of Fe content at 350 ℃. The increase of the elevated temperature strength of the composites is mainly attributed to the refinement of δ-Al4（（Fe,Mn）Si2 phase and the increase of the volume fraction of the Fe-bearing compounds. Compared with the composites without USV, the RC composites assisted with USV have thinner mechanical mixing layer in wear test, which corresponds to smaller wear rate.

关键词： Fe-bearing phase Metal matrix composites Microstructure Properties Ultrasound

Hyponormal Dual Toeplitz Operators on the Orthogonal Complement of the Harmonic Bergman Space

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Acta Mathematica Sinica,English Series 2023年第5期39卷 846-862页

作者： chong Chao WANG Xian Feng ZHAO College of Mathematics and Physics Wenzhou UniversityWenzhou 325035P.R.China College of Mathematics and Statistics Chongqing UniversityChongqing 401331P.R.China

In this paper,we mainly study the hyponormality of dual Toeplitz operators on the orthogonal complement of the harmonic Bergman *** we show that the dual Toeplitz operator with the bounded symbol is hyponormal if and only if it is *** we obtain a necessary and sufficient condition for the dual Toeplitz operator S_(φ) with the symbol φ(z)=az^(n1zm1)+bz^(n2zm2)(n1,n2,m1,m2∈N and a,b∈C)to be ***,we show that the rank of the commutator of two dual Toeplitz operators must be an even number if the commutator has a finite rank.

关键词： Dual Toeplitz operator harmonic Bergman space normal hyponormal

Ni-mediated C–N activation of amides and derived catalytic transformations

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Science China Chemistry 2017年第11期60卷 1413-1424页

作者： Yuan Gao chong-Lei Ji Xin Hong Department of Chemistry Zhejiang UniversityHangzhou 310027China

Amide, as a ubiquitous functional group, is essential in various aspects of chemistry and biology. Although the history of studying amide is rich and fruitful, the synthetic application of amide is very limited due to the inertness of amide C–N bond. Recently,significant advances have been achieved towards the nickel-mediated C–N activation of amides. This approach allows a facile generation of acyl-nickel intermediates, and a number of unique transformations have been designed and realized based on the amide C–N bond activation. Focused on the catalytic transformation, this review summarizes and categorizes the recent advances on the synthetic applications of Ni-mediated C–N bond activation of amides.

关键词： C-N activation amide nickel homogeneous catalysis cross coupling

Suppressing laser phase noise in an optomechanical system

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Frontiers of physics 2022年第1期17卷 59-69页

作者： Yexiong Zeng Biao Xiong chong Li School of Physics Dalian University of TechnologyDalian116024China College of Physics and Electronic Science Hubei Normal UniversityHuangshi435002China

We propose a scheme to suppress the laser phase noise without increasing the optomechanical single-photon coupling *** the scheme,the parametric amplification terms,created by Kerr and Duffing nonlinearities,can restrain laser phase noise and strengthen the effective optomechanical coupling,***,decreasing laser phase noise leads to increasing thermal noise,which is inhibited by bringing in a broadband-squeezed vacuum *** reflect the superiority of the scheme,we simulate quantum memory and stationary optomechanical entanglement as examples,and the corresponding numerical results demonstrate that the laser phase noise is extremely *** method can pave the way for studying other quantum phenomena.

关键词： optomechanical system quantum entanglement quantum memory

Oxidation behavior of Ni-based superalloy GH4738 under tensile stress

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Rare Metals 2024年第8期43卷 3913-3920页

作者： Ji-chong Hu Hai-Liang Huang chong-chong Wu Xiao-Yu Sun Jie Wang Yan-Hong Yang Jing-Long Qu Liang Jiang Jin-He Dou Yang Chen Institute for Advanced Studies in Precision Materials Yantai UniversityYantai 264005China Department of Management and Engineering Linkoping University58183LinkopingSweden Shi-Changxu Innovation Center for Advanced Materials Institute of Metal ResearchChinese Academy of SciencesShenyang110016China Gaona Aero Material Co. LtdBeijing 100081China College of Artificial Intelligence and Big Data Shandong First Medical University and Shandong Academy of Medical SciencesJinan250117China

Revealing the oxidation behavior of superalloys is crucial for optimizing material properties and extending service *** study investigated the oxidation behavior of superalloy GH4738 under stress states at 850℃.High-throughput specimens were fabricated to withstand different stresses at the same *** oxidation s amples were analyzed using the mass gain method to obtain oxidation kinetic *** results show that the external stress below 200 MPa could improve the oxidation resistance of the *** tensile stress increasing,the oxide layer becomes thinner,denser and more complete,while internal oxidation *** tensile stress alters the structure of the external oxide layer from a two-layer to a threelayer *** Cr_(2)O_(3) oxide layer inhibits the outward diffusion of Ti,leading to Ti enrichment at the oxide-matrix interface and altering the oxidation mechanism of GH4738.

关键词： Ni-based Superalloy Oxidation behavior Tensile stress Oxide layer