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Zwitterionic ring-opening polymerization of macrocyclic ethyleneoxy-substituted carbonate:Access to cyclic PEG-like polycarbonate

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Chinese Chemical Letters 2024年第3期35卷 282-286页

作者： Jin Huang Jinwen Li Rui Yan Yuanyuan Qu Fengzhen Guo Lei shen Can-liang ma Jie Sun Zhenjiang Li Kai Guo State Key Laboratory of materials-Oriented Chemical Engineering College of Biotechnology and Pharmaceutical EngineeringNanjing Tech UniversityNanjing 211816China Institute of Nanjing Advanced Biomaterials&Processing Equipment Lishui Economic Development ZoneNanjing 211299China

The innovation in polymer design to rival conventional polyethylene glycol(PEG)is an important approach to achieving a more sustainable ***,cyclic PEG-like polycarbonates having high molecular weight(4.4–49.5 kg/mol)were enabled through zwitterionic ring-opening polymerization(ZROP)of macrocyclic carbonates(MCs)mediated by N-heterocyclic carbene(NHC).The thermodynamic behavior of polymerization depends on the ring size of *** this process,the ZROP of 11-membered MC was driven by the change of enthalpy(ΔH_(p))which differed from the ZROP of 14-membered MC driven by the entropic change(ΔS_(p)).Cyclic polycarbonates depicted improved thermostability(T_(d5%)≥204℃)and higher glass transition temperatures(T_(g)>–40℃)in comparison to their linear analogues(T_(d5%)≤185℃,T_(g)~–50℃).In addition,the mechanism of ZROP of MC was addressed through computational study.A distinct mechanism of polymerization distinguishable from the well-known NHC-mediated ZROP of cyclic esters was revealed,where the zwitterion from nucleophilic addition to MC,*** intermediate,cannot be ring-opened probably due to the delocalization of negative charge on the carbonate group,but serves as an active center for the *** comparison to PEG,the attained polymer demonstrated comparable hydrophilic and biocompatible properties,as revealed by the results of contact angle and in vitro cytotoxicity studies,suggesting that cyclic polycarbonate hold the promise as the alternative of PEG.

关键词： Zwitterionic ring-opening polymerization Cyclic polycarbonate macrocycles Tetrahedral intermediate NHC carbene

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Synergistic effects of carbon cycle metabolism and photosynthesis in Chinese cabbage under salt stress

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Horticultural Plant Journal 2024年第2期10卷 461-472页

作者： Hao Liang Qiling Shi Xing Li Peipei Gao Daling Feng Xiaomeng Zhang Yin Lu Jingsen Yan Shuxing shen Jianjun Zhao Wei ma State Key Laboratory of North China Crop Improvement and Regulation Key Laboratory of Vegetable Germplasm Innovation and Utilization of HebeiCollaborative Innovation Center of Vegetable Industry in HebeiCollege of HorticultureHebei Agricultural UniversityBaodingHebei 071000China

Chinese cabbage(Brassica rapa ssp. pekinensis) has a long cultivation history and is one of the vegetable crops with the largest cultivation area in China. However, salt stress severely damages photosynthesis and hormone metabolism, nutritional balances, and results in ion toxicity in plants. To better understand the mechanisms of salt-induced growth inhibition in Chinese cabbage, RNA-seq and physiological index determination were conducted to explore the impacts of salt stress on carbon cycle metabolism and photosynthesis in Chinese cabbage. Here, we found that the number of thylakoids and grana lamellae and the content of starch granules and chlorophyll in the leaves of Chinese cabbage under salt stress showed a time-dependent response, first increasing and then decreasing. Chinese cabbage increased the transcript levels of genes related to the photosynthetic apparatus and carbon metabolism under salt stress, probably in an attempt to alleviate damage to the photosynthetic system and enhance CO_(2) fixation and energy metabolism. The transcription of genes related to starch and sucrose synthesis and degradation were also enhanced;this might have been an attempt to maintain intracellular osmotic pressure by increasing soluble sugar concentrations. Soluble sugars could also be used as potential reactive oxygen species(ROS) scavengers, in concert with peroxidase(POD)enzymes, to eliminate ROS that accumulate during metabolic processes. Our study characterizes the synergistic response network of carbon metabolism and photosynthesis under salt stress.

关键词： Chinese cabbage Salt stress Carbon metabolism Photosynthesis Chloroplast

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钩虾和蜾蠃蜚群落在日本对虾养殖池塘中变动规律的研究

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中国海洋大学学报（自然科学版） 2012年第1期42卷 59-66页

作者：钟源马甡中国海洋大学海水养殖教育部重点实验室山东青岛266003

2009年4～7月,对移入日本对虾养殖池的钩虾和蜾蠃蜚群落进行了研究。共调查到2种钩虾,3种蜾蠃蜚。钩虾的优势种为中华原钩虾;蜾蠃蜚的优势种具有明显的交替性,放养后前53d,优势种为大蜾蠃蜚,78d后,优势种为隐居蜾蠃蜚。钩虾群落的物种... 详细信息

2009年4～7月,对移入日本对虾养殖池的钩虾和蜾蠃蜚群落进行了研究。共调查到2种钩虾,3种蜾蠃蜚。钩虾的优势种为中华原钩虾;蜾蠃蜚的优势种具有明显的交替性,放养后前53d,优势种为大蜾蠃蜚,78d后,优势种为隐居蜾蠃蜚。钩虾群落的物种多样性(H′)与均匀度(J)在放养当天达到最高,放养后第67天出现差异显著;蜾蠃蜚群落的物种多样性(H′)与均匀度(J)在放养后第64天最高,第90天出现差异显著。钩虾的生物量和丰度放养后第30天达到最大值,随后快速下降;蜾蠃蜚的生物量和丰度放养后第14天达到最大值,其丰度在第64天达到第二个高峰。同时,钩虾和蜾蠃蜚群落不同体长个体的丰度百分比差异明显,表现出一定的周期性变化规律。由此,初步分析了引起群落变化的两类原因,提出了钩虾和蜾蠃蜚群落结构的调控方案。

关键词：钩虾蜾蠃蜚群落变动规律虾池

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Strengthening strategy for high-performance friction stir lap welded joints based on 5083 Al alloy

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International Journal of Minerals,Metallurgy and materials 2024年第11期31卷 2498-2507页

作者： Yujia shen Jijie Wang Beibei Wang Peng Xue Fengchao Liu Dingrui Ni Bolv Xiao Zongyi ma College of material Science and Engineering Shenyang Aerospace UniversityShenyang 110136China Shi-changxu Innovation Center for Advanced materials Institute of Metal ResearchChinese Academy of SciencesShenyang 110016China CAS Key Laboratory of Nuclear materials and Safety Assessment Institute of Metal ResearchChinese Academy of SciencesShenyang 110016China Binzhou Institute of Technology Shandong Key Laboratory of Advanced Aluminium Materials and TechnologyWeiqiao-UCAS Science and Technology ParkBinzhou 256606China Centre of Excellence for Advanced materials Dongguan 523808China

During aircraft,ship,and automobile manufacturing,lap structures are frequently produced among Al alloy skins,wall panels,and *** occurrence of welding defects severely decreases mechanical properties during friction stir lap welding(FSLW).This study focuses on investigating the effects of rotation rate,multipass welding,and cooling methods on lap defect formation,microstructural evolution,and mechanical *** defects were eliminated by decreasing welding speed,applying two-pass FLSW with a small welding tool,and introducing additional water cooling,thus leading to a remarkable increase in effective sheet thickness and lap *** above strategy yielded defect-free joints with an ultrafine-grained microstructure and increased tensile shear force from 298 to 551 N/*** fracture behavior of FSLW joints was systematically studied,and a fracture factor of lap joints was proposed to predict their fracture *** reducing the rotation rate,using two-pass welding,and employing additional water cooling strategies,an enlarged,strengthened,and defect-free lap zone with refined ultrafine grains was achieved with a quality comparable to that of lap welds based on 7xxx Al ***,this study provides a valuable FSLW method for eliminating hook defects and improving joint performance.

关键词： friction stir lap welding defect control microstructure fracture mechanisms mechanical properties

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Solid polymer electrolyte-based high areal capacity all-solid-state batteries enabled with ceramic interlayers

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Nano Research 2024年第10期17卷 8803-8808页

作者： Chenji Hu Daiqian Chen Yage Huang Guoyong Xue Xi Liu Jingshu Wang Jun ma Bowen Chen Qi Chen Linsen Li Yanbin shen Liwei Chen School of Chemistry and Chemical Engineering in-situ Center for Physical SciencesShanghai Electrochemical Energy Device Research Center(SEED)and Frontiers Science Center for Transformative MoleculesShanghai Jiao Tong UniversityShanghai 200240China i-Lab CAS Center for Excellence in NanoscienceSuzhou Institute of Nano-Tech and Nano-Bionics(SINANO)Chinese Academy of SciencesSuzhou 215123China IDONANO Co Ltd Shanghai 201614China Future Battery Research Center Global Institute of Future TechnologyShanghai Jiao Tong UniversityShanghai 200240China

Solid polymer electrolytes(SPEs)based all-solid-state batteries(ASSBs)have attracted extensive attention as a promising candidate for next-generation energy storage *** ASSBs require high fabrication pressure to achieve high areal capacity,under which,however,SPEs struggle and risk damage or failure due to their low mechanical *** is also a lack of study on complex stress and strain SPEs experience during ASSB cell assembly ***,ceramic solid electrolytes are selected as interlayers to address the stress-strain conditions during *** a result,high areal capacity ASSBs with a LiCoO2 loading of 12 mg·cm^(-2) were assembled with SPE-based composite *** 200 cycles were carried out for these cells at a current density of 1 ma·cm^(-2) under room *** capacity decay of the battery at 200 cycles is observed to be as low as 0.06% per *** work identifies a critical issue for application of SPEs in ASSBs and provides a potential strategy for the design of SPE-based ASSBs with high specific energy and long cycle life.

关键词： all-solid-state batteries ceramic interlayer solid polymer electrolyte high areal capacity

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Interval analysis for neural networks with application to fault detection

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Science China(Information Sciences) 2024年第11期67卷 222-237页

作者： Zhenhua WANG Youdao ma Song ZHU Thach Ngoc DINH Yi shen Department of Control Science and Engineering Harbin Institute of Technology National Key Laboratory of Complex System Control and Intelligent Agent Cooperation School of mathematics China University of Mining and Technology The CEDRIC-Lab Conservatoire National des Arts et Métiers (CNAM)

This paper investigates an interval analysis method for neural networks and applies it to fault detection for systems with unknown but bounded measurement noise. First, a novel interval analysis method is presented, which can compute the bounds of the output of a feedforward neural network subject to a bounded input. By applying the proposed interval analysis method to a network trained with fault-free system data, adaptive thresholds for fault detection are computed. Finally, one can acquire fault detection results via a fault detection strategy. The proposed method can achieve tight bounds of the network output and employ simple operations, which leads to accurate fault detection results and a low computational burden.A numerical simulation and an experiment on an AC servo motor are given to illustrate the effectiveness and superiority of the proposed method.

关键词： interval analysis feedforward neural network fault detection adaptive thresholds

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Covalent triazine frameworks modified by ultrafine Pt nanoparticles for efficient photocatalytic hydrogen production

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Nano Research 2024年第6期17卷 4908-4915页

作者： Xu Han Xueying Ge Wen-Wen He Wangwang shen Tao Zhou Jian-Sen Wang Rong-Lin Zhong Abdullah mal-Enizi Ayman Nafady shengqian ma School of Chemistry and Life Science Advanced Institute of Materials ScienceChangchun University of TechnologyChangchun 130012China Laboratory of Theoretical and Computational Chemistry Institute of Theoretical ChemistryCollege of ChemistryJilin UniversityChangchun 130021China Department of Chemistry University of North Texas1508 W.Mulberry St.DentonTX 76201USA Department of Chemistry College of ScienceKing Saud UniversityRiyadh 11451Saudi Arabia

Pt nanoparticles(PtNPs)as active species have always been considered as one of the best semiconductor materials for photocatalytic hydrogen *** this study,a Schottky heterojunction has been successfully constructed by evenly loading ultrafine PtNPs onto a triazine-based covalent organic frameworks(COFs).This strategy maintained the high activity of these ultra-small PtNPs while maximizing the utilization of the Pt active *** fabricated PtNPs@covalent triazine-based framework-1(CTF-1)composite accomplished a significantly high rate of hydrogen evolution(20.0 mmol·g^(−1)·h^(−1),apparent quantum efficiency(AQE)=7.6%,atλ=450 nm)with 0.40 wt.%Pt loading,giving rise to a 44-fold-increase in the efficiency of the photocatalytic hydrogen production compared to the pristine *** calculations revealed that the strong electron transfer(Q(Pt)=−0.726 qe,in the analysis of Bader charge,Q(Pt)is the charge quantity transferred from Pt cluster to CTF-1,and qe is the unit of charge transfer quantity)between PtNPs and CTF-1 triggers a strong interaction,which makes PtNPs being firmly attached to the structure of CTF-1,thereby enabling high stability and excellent hydrogen production ***,the hydrogen binding free energy(ΔGH*)of PtNPs@CTF-1 is much lower than that of the unmodified CTF-1,leading to a much lower intermediate state and hence a significant improvement in photocatalytic *** overall findings of this work provide a new platform to incorporate metallic NPs into COFs for the design and fabrication of highly efficient photocatalysts.

关键词： Pt nanoparticles covalent triazine-based framework-1(CTF-1) photocatalysts hydrogen evolution reaction

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EZH2 is a prognostic factor associated with tumor stemness and immune infiltration in skull base chordoma

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Genes & Diseases 2024年第5期11卷 85-87页

作者： Qian Liu Mingxuan Li Yujia Xiong Yutao shen Tianshun ma Tianhao Zhang Xiaohong R.Yang Yazhuo Zhang Jiwei Bai Beijing Neurosurgical Institute Capital Medical UniversityBeijing 100070China Department of Neurosurgery Beijing Tiantan HospitalCapital Medical UniversityBeijing 100070China Division of Cancer Epidemiology and Genetics National Cancer InstituteNIHDHHSBethesdaMD 20892USA

Enhancer of zeste homolog 2(EZH2),an epigenetic regulator that inhibits transcription primarily through trimethylation of Lys-27 in histone 3(H3K27me3),has been reported to play an important role in the regulation of cell cycle,autophagy,and apoptosis,and DNA damage repair.1 EZH2 is highly expressed in a variety of cancers including prostate cancer,breast cancer,and renal clear cell carcinoma,and is associated with adverse prognosis.1 Moreover,it has been reported that EZH2 might increase tumor stemness and metastasis capacity and inhibit antitumor immunity by affecting T cells,NK cells,macrophages,and immune checkpoints.2,3 However,the prognostic value and the mechanism of EZH2 have not been investigated in *** this study,RNA sequencing and whole genome sequencing data based on 48 skull base chordomas as well as immunohistochemistry of paraffin sections were analyzed to elucidate the role of EZH2 in skull base *** found copy number gain mediated high EZH2 expression is associated with tumor stemness,M2 macrophage infiltration,and adverse prognosis in ***,we demonstrated that EZH2 promotes the proliferation,migration,and invasion of chordoma cells in in vitro cell experiments.

关键词： EZH2 immunity invasion

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The Effect of siRNA-VEGF on the Growth of REC in Retina Pigment Epithelial Cell and Retinal Endothelial Cell Co-culture System

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Eye Science 2011年第2期26卷 75-79页

作者： Jin ma Zhaomeng shen Qianru Zhang Tiepei Zhu Ke Yao Eye Center the Second Affiliated Hospital School of Medicine of Zhejiang UniversityHangzhou 310009 China

Purpose:To investigate the effect of small interfering RNA (siRNA)targeting VEGF of retinal pigment epithelium (RPE) cells on the growth activity of human retinal vascular endothelial cells (RECs) under a co-culture ***:By applying the vector.(pGPU6)-based siRNA plasmid gene silence system,we specifically silenced VEGF expression of RPE cells (ARPE-19) through plasmid (pG-PU6-VEGFA-siRNA)*** transcription polymerase chain reaction(RT-PCR) was applied for selecting the most efficient siRNA segment among three pGPU6-VEGF-siRNA groups (siRNA-1,siRNA-2 and siRNA-3).Treated RPE cells were co-cultured with RECs in a co-culture system made up of a 24-well culture plate and transwell inserts assembled inside During 7-day culture period,the growth ca-pacity of RECs were observed and tested in the form of cell counting *** groups were established in this study:RPE cells transfected with pGPU6-VEGF-siRNA and co-cultured with RECs (group A),RPE cells transfected with siR-NA null vector and co-cultured with RECs (group B),and RECs cultured alone (group C).Results:After transfection,VEGF expression levels of RPE cells in three pGPU6-VEGF-siRNA groups (siRNA-1,siR-NA-2 and siRNA-3)evaluated by RT-PCR were 2.56 ±0.45,1.17 ±0.38 and 4.39 ±0.51,respectively (n =10).siRNA-2 was selected as the foremost segment for transfection (P 0.05,dunnett's test).RECs in group A proliferated muchfaster during the first four days ***:Delivery of siRNA targeting VEGF plays an efficient role in down-regulating VEGF expression in RPE cells,therefore modulating the growth activity of RECs under a co-culture system in *** application of this techniqu

关键词：血管内皮生长因子血管内皮细胞 siRNA 共培养体系人视网膜上皮细胞色素经济共同体

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Preparation and Properties of Fe-MOF Based Aerogels

Preparation and Properties of Fe-MOF Based Aerogels

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河南省化学会2018年学术年会

作者： Zhi-hong Zhang Kuan Tian Ya-shen ma Bin Hu Henan Provincial Key Laboratory of Surface and Interface Science Zhengzhou University of Light Industry

a series of aerogels(MOAs)such as Fe-MOFs,Fe-MOFs/CN,Fe-Ti-MOFs-NH were prepared by *** morphology of the composites was characterized by scanning electron microscopy(SEM),X-ray diffraction(XRD)and Fourier transform infrared spectroscopy(FTIR).The reaction temperature,reaction time,addition of raw materials,molar ratio of metal to ligand and other factors were found to affect the formation of airgel,and Fe-MOFs/CNappeared in the hole and lamellar *** catalytic degradation performance of Fe-MOAs was the best,and the adsorption of Congo-red(Congo)was complete in10 min,and the effect of Rhodamine B(RhB)on the degradation of organic dyes was evaluated by UV-Vis *** 100 min adsorption degradation completely.

关键词： Organic dyes Catalytic degradation Fe-MOAs

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