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Nitrogen-doped carbon dots as photocatalysts for organic synthesis:Effect of nitrogen content on catalytic activity

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Nano Research 2024年第6期17卷 4825-4833页

作者： Kai-Kai niu Chao-Qun Ma Rui-Zhi Dong Hui Liu Sheng-Sheng Yu Ling-Bao xing School of Chemistry and Chemical Engineering Shandong University of TechnologyZibo 255000China

Regulating the doping of carbon dots(CDs)and the generation of reactive oxygen species(ROS)is essential to selectively control their application in photocatalytic organic *** study successfully synthesized five newly developed nitrogen-doped carbon dots(CDs 1-5)with varying nitrogen content,which have the ability to generate ROS when exposed to light radiation,specifically superoxide anion radicals(O_(2)•-)and singlet oxygen(^(1)O_(2)).The utilization of the aforementioned nitrogen-doped CDs as photocatalysts enables the realization of their potential in facilitating efficient photocatalytic organic ***,it was observed that the photocatalytic efficiency exhibited a gradual decrease when the nitrogen content in the CDs *** order to provide more evidence for this claim,we employed a set of five CDs in the context of photocatalytic dehalogenation ofα-bromoacetophenone,photocatalytic oxidative coupling reaction of amines to imines,photooxidation reaction of sulfides to sulfoxides,and cross-dehydrogenation coupling(CDC)reaction,in which it was further observed that there was a steady decrease in the yields of photocatalytic organic reactions as the nitrogen content in CDs ***,CDs 1 exhibited the best photocatalytic efficiency,thereby reinforcing the hypothesis that a higher nitrogen content corresponds to a decreased catalytic *** study not only investigates the impact of the nitrogen content on the catalytic performance of CDs,but also offers valuable insights for the future utilization of CDs for photocatalytic organic reactions in water.

关键词： carbon dots nitrogen-doped reactive oxygen species photocatalysis

Construction of pyrene-based hydrogen-bonded organic frameworks as photocatalysts for photooxidation of styrene in water

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Chinese Chemical Letters 2024年第10期35卷 394-398页

作者： Rongxin Zhu Shengsheng Yu Xuanzong Yang Ruyu Zhu Hui Liu Kaikai niu Lingbao xing School of Chemistry and Chemical Engineering Shandong University of TechnologyZibo 255000China

Using hydrogen-bonded organic frameworks(HOFs)as photosensitizers to perform photocatalytic oxidation reactions under green and mild conditions is still a challenge for the application of HOFs *** study presents a novel approach that exploits HOFs to enhance the efficiency of photocatalytic oxidation for achieving visible light catalytic oxidation of styrene and its derivatives in the aqueous *** using 1,3,6,8-tetrakis(p-benzoic acid)pyrene(H_(4)TBAPy)as the monomer,a pyrene-based hydrogen-bonded organic framework(PFC-1)with a microporous structure was successfully *** with monomer H_(4)TBAPy,due to the exciton effect and the interlayer confinement of HOFs,the singlet oxygen(1O_(2))production efficiency is significantly improved,which has great potential in photocatalytic oxidation ***,the practicality of PFC-1 as a photocatalyst was studied,and the photocatalytic oxidation of styrene and its derivatives in aqueous solution was achieved under visible light with high catalytic efficiency,indicating that PFC-1 has significant potential to promote photocatalytic oxidation reactions under mild *** utilization of HOFs as photosensitizers in this straightforward approach enables the attainment of green photocatalytic oxidation,hence expanding the potential applications of HOFs materials within the realm of photocatalysis.

关键词： Pyrene Hydrogen-bonded organicframeworks Singlet oxygen Photocatalysis Styrene

Analysis and Improvement of an Authentication Scheme for Fog Computing Services

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Wuhan University Journal of Natural Sciences 2024年第3期29卷 209-218页

作者： HUO Yuyan KANG Baoyuan niu Shufang LI Anqian zuo Xinyu School of Software Tiangong UniversityTianjin 300387China School of Computer Science and Technology Tiangong UniversityTianjin 300387China

Fog computing utilizes devices in the edge network to transmit data with very low latency and supports high mobility. However, fog computing inherits security and privacy problems from cloud computing. Therefore, various privacy schemes for fog computing have been proposed to prevent different types of attacks. Recently, Weng et al proposed a fog computing authentication scheme;after analyzing, we found that Weng et al's scheme cannot resist user tracking attack and user impersonation attack. Then, we propose an improved scheme through adding a password, modifying the calculation method of Ei, and adding timestamps. In addition, we also compare the improved scheme with existing authentication schemes in terms of security and computational efficiency. The results show that the improved scheme is more secure and has less computation.

关键词： authentication scheme fog computing security

Metal natural product complex Ru-procyanidins with quadruple enzymatic activity combat infections from drug-resistant bacteria

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Acta Pharmaceutica Sinica B 2024年第5期14卷 2298-2316页

作者： Jie Shan Xu Jin Cong Zhang Muchen Huang Jianghao xing Qingrong Li Yuyu Cui Qiang niu Xu Lin Chen Xianwen Wang Department of Burns the First Affiliated Hospital of Anhui Medical UniversityHefei 230022China School of Biomedical Engineering Research and Engineering Center of Biomedical MaterialsAnhui Provincial Institute of Translational MedicineAnhui Medical UniversityHefei 230032China Division of Gastroenterology the First Affiliated Hospital of USTCDivision of Life Science and MedicineUniversity of Science and Technology of ChinaHefeiAnhui 230026China The Second Clinical Medical College Anhui Medical UniversityHefei 230022China Department of Oncology the First Affiliated Hospital of Anhui Medical UniversityHefei 230022China College and Hospital of Stomatology Anhui Medical UniversityKey Lab.of Oral Diseases Research of Anhui ProvinceHefei 230032China

Bacterial infection hampers wound repair by impeding the healing ***,inflammation at the wound site triggers the production of reactive oxygen species(ROS),causing oxidative stress and damage to proteins and *** can lead to chronic wounds,posing severe ***,eliminating bacterial infection and reducing ROS levels are crucial for effective wound ***,possessing enzyme-like catalytic activity,can convert endogenous substances into highly toxic substances,such as ROS,to combat bacteria and biofilms without inducing drug ***,the current nanozyme model with single enzyme activity falls short of meeting the complex requirements of antimicrobial ***,developing nanozymes with multiple enzymatic activities is ***,we engineered a novel metalloenzyme called Ru-procyanidin nanoparticles(Ru-PC NPs)with diverse enzymatic activities to aid wound healing and combat bacterial *** acidic conditions,due to their glutathione(GSH)depletion and peroxidase(POD)-like activity,Ru-PC NPs combined with H2O2 exhibit excellent antibacterial ***,in a neutral environment,the Ru-PC NPs,with catalase(CAT)activity,decompose H2O2 to O2,alleviating hypoxia and ensuring a sufficient oxygen ***,Ru-PC NPs possess exceptional antioxidant capacity through their superior superoxide dismutase(SOD)enzyme activity,effectively scavenging excess ROS and reactive nitrogen species(RNS)in a neutral *** maintains the balance of the antioxidant system and prevents ***-PC NPs also promote the polarization of macrophages from M1 to M2,facilitating wound *** importantly,Ru-PC NPs show good biosafety with negligible *** vivo wound infection models have confirmed the efficacy of Ru-PC NPs in inhibiting bacterial infection and promoting wound *** focus of this work highlights the quadruple enzymatic activity of Ru-PC NPs and its potential to reduce inf

关键词： Nanozymes Quadruple enzymatic activity Antibacterial therapy Wound therapy RNA-seqAnti-inflammatory Reactive oxygen species Reactive nitrogen species

Mineralogical properties and co-sintering characteristics of fluxed iron ore with magnetite concentrates

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Journal of Iron and Steel Research International 2024年第2期31卷 318-328页

作者： Le-le niu Zheng-jian Liu Jian-liang Zhang Yao-zu Wang Zhen-xing Yang Si-da Li Chang-dong Shan Ben Feng School of Metallurgical and Ecological Engineering University of Science and Technology BeijingBeijing100083China Institute of Artificial Intelligence University of Science and Technology BeijingBeijing100083China Xinxing Casting Pipe Xinjiang Co. Bayingol841300XinjiangChina

To investigate the feasibility of co-sintering of fluxed iron ore with magnetite concentrates, the mineralogical properties of a novel fluxed iron ore were studied using particle size analysis, microscopic morphology characterization, and X-ray diffraction Rietveld analysis. Following that, the experiments for granulation performance and basic sintering characteristics were designed under seven different fluxed iron ore ratios, and the integrated ranking of different fluxed iron ore ratios was determined using gray relation analysis. Finally, the results of the industrial trails were combined with the feasibility analysis. Test and experimental results show that the fraction of the fluxed iron ore particles larger than 0.5 mm can account for more than 48%, and the particles have two morphologies: spherical-rough and flaky-smooth. Ca elements are found in the form of calcite (CaCO3) and dolomite (CaMg(CO3)2). The average particle size of granules and powder removal rate can be improved from 2.50 to 3.16 mm and 39.60% to 24.20%, respectively, with the increase in the fluxed iron ore ratio. Furthermore, the fluxed iron ore can improve assimilability and liquid fluidity of magnetite concentrates. In terms of overall granulation performance and sintering characteristics, the fluxed iron ore ratios are graded from best to worst as follows: 12%, 15%, 9%, 18%, 21%, 6% and 3%. The industrial trails show that when the fluxed iron ore ratio is increased, the beneficial effect of the superior sintering characteristics of the fluxed iron ore itself is ideally balanced with the negative effect of the lower amount of additional CaO at 12% ratio, and thus, it is feasible to bring the fluxed iron ore into production at a level of roughly 12%.

关键词： Fluxed iron ore Magnetite concentrate Granulation performance Sintering characteristics Gray relation analysis

Penumbra-targeted CircOGDH siRNA-loaded nanoparticles alleviate neuronal apoptosis in focal brain ischaemia

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Stroke & Vascular Neurology 2024年第2期9卷 134-144,I0396-I0413页

作者： Yanfang Liu Tianyuan Zhang xing Zou Zhongwen Yuan Yufeng Li Jiankun Zang niu He Lizhen He Anding Xu Dan Lu Department of Neurology and Stroke Center Jinan University First Affiliated HospitalGuangzhouGuangdongChina Department of Clinical Neuroscience Institute The First Affiliated Hospital of Jinan UniversityGuangzhouGuangdongChina Key Lab of Guangzhou Basic and Translational Research of Pan-vascular Diseases The First Affiliated Hospital of Jinan UniversityGuangzhouChina

Background Nanoparticles(NPs)are a class of substances that can be loaded with therapeutic agents delivered to specific *** our earlier research,we identified a neuron-derived circular RNA(circRNA),circular oxoglutarate dehydrogenase(CircOGDH),as a promising therapeutic target for acute ischaemic *** study dedicated to explore a prospective preliminary strategy of CircOGDH-based NP delivered to the ischaemic penumbra region in middle cerebral artery occlusion/reperfusion(MCAO/R)*** Immunofluorescence in primary cortex neurons and in vivo fluorescence imaging revealed endocytosis of Poly(lactide-co-glycolide)(PLGA)poly amidoamine(PAMAM)@CircOGDH small interfering RNA(siRNA)*** blotting analysis and CCK8 assay were performed to evaluate the apoptotic level in ischaemic neurons treated with PLGA–PAMAM@CircOGDH siRNA *** reverse transcription PCR experiments,mice behaviour test,T2 MRI analysis,Nissl and TdT-mediated dUTP nick end labeling(TUNEL)co-staining were performed to evaluate the apoptosis level of ischaemic penumbra neurons in MCAO/R *** evaluation of NPs in MCAO/R mice was detected by blood routine examination,liver and kidney function examination and HE *** PLGA–PAMAM@CircOGDH siRNA NPs were successfully *** of PLGA–PAMAM@CircOGDH siRNA NPs in ischaemic neurons alleviated neuronal apoptotic level in vitro and in ***,mice behaviour test showed that the neurological defects of MCAO/R mice were significantly alleviated after the tail injection of PLGA–PAMAM@CircOGDH siRNA NPs,and no toxic effects were *** In conclusion,our results suggest that PLGA–PAMAM@CircOGDH siRNA NPs can be delivered to the ischaemic penumbra region and alleviate neuron apoptosis in MCAO/R mice and in ischaemic neurons;therefore,our study provides a desirable approach for using circRNA-based NPs for the treatment of ischaemic stroke.

关键词： OGD routine loaded

ZnGa_(2)S_(4):an infrared nonlinear optical material with large second-harmonic generation response and wide band gap

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Rare Metals 2024年第1期43卷 395-401页

作者： Chen-Yang Zhang Xiao-Nan niu Yan-Feng Wei Shu-xing Zhou Da-Qing Yang Ying Wang Jian Wang Bing-Bing Zhang College of Chemistry and Materials Science Key Laboratory of Medicinal Chemistry and Molecular Diagnosis of the Ministry of EducationState Key Laboratory of New Pharmaceutical Preparations and ExcipientsHebei UniversityBaoding 071002China Hubei Key Laboratory of Low Dimensional Optoelectronic Materials and Devices Hubei University of Arts and ScienceXiangyang 441053China Hubei Longzhong Laboratory Xiangyang 441000China Department of Chemistry and Biochemistry Wichita State UniversityKansas 67260USA

High-performance nonlinear optical(NLO)crystals are crucial devices to convert wavelength of solid-state *** play an indispensable role in the research of infrared NLO *** this work,ternary chalcogenide ZnGa_(2)S_(4) ... 详细信息

关键词： optical nonlinear harmonic

Single-cell RNA sequencing reveals abnormal transcriptome signature of erythroid progenitors in pure red cell aplasia

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Genes & Diseases 2024年第1期11卷 49-52页

作者： Yumei Liu Haiyue niu Jie Ren Zhiqin Wang Li Yan Limin xing Zonghong Shao Rong Fu Zhigang Cai Huaquan Wang Department of Hematology Tianjin Medical University General HospitalTianjin 300052China School of Basic Medical Sciences Tianjin Medical UniversityTianjin 300070China

Pure red cell aplasia(PRCA)is a bone marrow failure syndrome characterized by severe anemia,reticulocytopenia,selective reduction,and even the absence of bone marrow erythroid precursors,while leukocyte and platelet counts are normal.1 Acquired PRCA can be divided into primary and *** are mediated by immune *** in the quantity and dysfunction of committed erythroid progenitors(EPs),including burst forming uniterythroid(BFU-E)and colony forming unit-erythroid(CFU-E),may be the source of reduced erythropoiesis and needs to be elucidated.

关键词： progenitor anemia leukocyte

Design and Verification of Parallel Hip Exoskeleton Considering Output Torque Anisotropy

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Journal of Bionic Engineering 2024年第3期21卷 1305-1320页

作者： Jilong Xu Yunzhan niu Fucai Liu Engineering Research Center of the Ministry of Education for Intelligent Control System and Intelligent Equipment Yanshan UniversityQinhuangdao066004China Key Laboratory of Industrial Computer Control Engineering of Heibei Province Yanshan UniversityQinhuangdao066004China College of Mechanical Engineering Yanshan UniversityQinhuangdao066004China

In rehabilitation training,it is crucial to consider the compatibility between exoskeletons and human legs in ***,most exoskeletons today adopt an anthropomorphic serial structure,which results in rotational centers that are not precisely aligned with the center of the hip *** address this issue,we introduce a novel exoskeleton called the Parallel Hip Exoskeleton(PH-Exo)in this ***-Exo is meticulously designed based on the anisotropic law of output *** the friction of the drive components,a dynamic model of the human-machine complex is *** analysis demonstrates that PH-Exo not only exhibits outstanding torque performance but also achieves high controllability in both flexion/extension and adduction/abduction ***,a robust controller is designed to address model uncertainty,friction,and external *** experiments indicate that under the control of the robust controller,each motor achieves excellent tracking performance.

关键词： Hip exoskeleton Parallel mechanism Misalignment Anisotropy Output torque