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High-temperature Thermo-oxidative Aging of Vulcanized Natural Rubber Nanocomposites:Evolution of Microstructure and Mechanical Properties

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Chinese Journal of Polymer Science 2023年第8期41卷 1287-1297,I0010页

作者： Zhou-Xian Li Yi-Ran Kong Xiang-Fei Chen ya-Jiang Huang ya-dong lv Guang-Xian Li College of polymer science and engineering State key laboratory of polymer materials engineering of ChinaSichuan UniversityChengdu 610065China

The aging of natural rubber(NR)at high temperatures will seriously affect its service lifetime in many key *** the present work,the changes in microstructure and mechanical properties of semi-efficient vulcanized NR/carbon black(CB)vulcanizates during thermooxidative aging at high temperatures(150-200℃)and a moderate temperature(95℃)were *** high temperatures,a two-stage aging behavior,which was characteristic of a first rapid decline and then a continuous rise in the crosslinking density(ve),was identified and was found to be closely related to the depletion behavior of *** surface cracking behavior observed in the second stage of high-temperature aging was discussed in terms of the grafting reaction of macromolecular radicals on CB particles and thermal *** contrast,the aging of NR at moderate temperatures was much mild,which featured a continuous increase in ve and an oxidation mechanism dominated by peroxy radicals attacking double *** general,the mechanical properties of NR vulcanizates during high-temperature aging depended on the competition effects of structural evolution in the crosslinked network and oxidation-induced chain scission.

关键词： Natural rubber nanocomposites High-temperature Thermo-oxidative aging

Effect of h-BN rods on high-temperature properties of alumina-carbon refractory

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Journal of Iron and Steel Research International 2025年第1期32卷 115-128页

作者： ya-ge Li Shuai-bing Wu Feng Liang Zhong Huang Tu Long Long dong Jun-yi lv Hong-juan Duan Biao Wen Yong Liu Hai-jun Zhang The State Key Laboratory of Refractories and Metallurgy Wuhan University of Science and TechnologyWuhan430081HubeiChina Sinosteel Luoyang Institute of Refractories Research Co. Ltd.Luoyang471039HenanChina

h-BN rods modified low-carbon alumina-carbon(Al_(2)O_(3)-C)refractories were prepared,and the effect of h-BN rod addition on the high-temperature properties was investigated and compared with commercial h-BN flake,carbon black,and carbon nanotubes *** results demonstrated that Al_(2)O_(3)-C refractories containing h-BN rods exhibited optimal high-temperature service performances,including 25%higher hot modulus of rupture,21.3%higher thermal shock strength residual ratio,20.9%lower in oxidation and 44.3%less in slag corrosion,compared to the counterpart specimens without ***,benefiting from the synergistic enhancement of the rod-like h-BN and in-situ generated SiC whiskers,the high-temperature service performances of h-BN rods containing specimens outperformed counterpart specimens containing commercial h-BN flake,carbon black,and carbon nanotubes,respectively.

关键词： Al_(2)O_(3)-C refractory h-BN rod Microstructure High-temperature service performance

An adjustable bio-sealing method for rock fracture leakage mitigation

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Journal of Rock Mechanics and Geotechnical Engineering 2025年第1期17卷 220-232页

作者： Zhihao dong Xiaohua Pan Chaosheng Tang Chao lv Bin Shi School of Earth Sciences and Engineering Nanjing UniversityNanjing210023China State Key Laboratory for GeoMechanics and Deep Underground Engineering China University of Mining and TechnologyXuzhou221116China

This study proposed a repeated adjustable mixture injection strategy(RAM)based microbial induced carbonate precipitation(MICP)for efficient mitigation of rock fracture *** fractures with small apertures were investigated,and bio-sealing experiments were conducted using five different cementation solution(CS)concentrations(0.25−2 M).The results showed that the RAM-based bio-sealing method can seal and bond the small aperture rock fractures with high efficiency and uniform precipitation by adjusting the CS *** RAM-based bio-sealing mechanism is attributed to the following four stages:(1)fixation of bacterial flocs onto the fracture surfaces,(2)precipitation of CaCO3 onto the fracture surfaces,(3)growth of pre-precipitated CaCO3 and adhesion of new-suspended CaCO3,and(4)bridging and clogging *** optimal CS concentration of 1 M resulted in a fracture filling rate up to 85%,a transmissivity reduction of 4 orders of magnitude,and a shear strength ranging from 512 kPa to 688 *** bio-sealing effect was found to be influenced by the CS concentration on bacterial attachment,calcium carbonate yield and calcium carbonate bulk *** CS concentration of 1 M promoted bacterial attachment,and increased calcium carbonate yield as well as calcium carbonate bulk density,while concentrations above 1 M had the opposite *** bulk density of calcium carbonate played a crucial role in the sealing and bonding performance of bio-sealed fractures,particularly at comparable filling ratios and bridging *** bulk density was regulated by the size of calcium carbonate crystals and was determined by Ca2+concentration in the *** study provides valuable insights into the RAM-based bio-sealing method,highlighting its potential for efficient rock fracture leakage mitigation through precise control of CS concentration and understanding the underlying mechanisms.

关键词： MICP Rock fracture Hydraulic and mechanical performance Bio-sealing

原位聚合水性聚氨酯/聚多巴胺粒子复合材料的制备及性能研究

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高分子学报 2019年第7期50卷 710-720页

作者：徐文卿吕亚栋孔米秋黄亚江李光宪四川大学空天科学与工程学院成都610065 四川大学高分子科学与工程学院成都610065 四川大学高分子材料工程国家重点实验室成都610065

通过原位聚合法制备了水性聚氨酯(WPU)/聚多巴胺粒子(PDA)复合材料,并进一步研究了PDA粒子的引入对WPU的热性能、力学性能及抗紫外老化性能的影响.首先通过多巴胺盐酸盐在氢氧化钠碱液中自发氧化聚合得到了平均粒径约为150 nm的PDA粒子... 详细信息

通过原位聚合法制备了水性聚氨酯(WPU)/聚多巴胺粒子(PDA)复合材料,并进一步研究了PDA粒子的引入对WPU的热性能、力学性能及抗紫外老化性能的影响.首先通过多巴胺盐酸盐在氢氧化钠碱液中自发氧化聚合得到了平均粒径约为150 nm的PDA粒子.随后以异佛尔酮二异氰酸酯、聚四氢呋喃二醇、2,2-二羟甲基丙酸为主要原料反应得到亲水性聚氨酯预聚体,然后加入PDA粒子的水分散液对预聚体进行乳化,最后以1,4-丁二醇扩链得到WPU/PDA复合材料.结果表明,PDA粒子的加入显著提高了WPU的热稳定性和力学性能.与纯WPU相比,当PDA粒子含量为0.5 wt%时,WPU/PDA复合材料的起始降解温度提高了22.7°C,拉伸强度和杨氏模量分别提高了37%和78%.同时,PDA粒子的加入也极大阻碍了紫外辐照老化后WPU表面裂纹的形成,有效抑制了材料的氧化降解.这主要是因为PDA粒子与WPU硬段的氨基甲酸酯基和脲基之间较强的相互作用以及PDA粒子本身的紫外吸收和自由基捕获能力.

关键词：聚多巴胺水性聚氨酯力学性能热稳定性抗紫外性能

Human neural stem cell-derived extracellular vesicles protect against ischemic stroke by activating the PI3K/AKT/mTOR pathway

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Neural Regeneration Research 2025年第11期20卷 3245-3258页

作者： Jiayi Wang Mengke Zhao dong Fu Meina Wang Chao Han Zhongyue lv Liang Wang Jing Liu Stem Cell Clinical Research Center The First Affiliated Hospital of Dalian Medical UniversityDalianLiaoning ProvinceChina Dalian Innovation Institute of Stem Cell and Precision Medicine DalianLiaoning ProvinceChina Institute(College)of Integrative Medicine Dalian Medical UniversityDalianLiaoning ProvinceChina

Human neural stem cell-derived extracellular vesicles exhibit analogous functions to their parental cells,and can thus be used as substitutes for stem cells in stem cell therapy,thereby mitigating the risks of stem cell therapy and advancing the frontiers of stem cell-derived *** lays a foundation for the development of potentially potent new treatment modalities for ischemic ***,the precise mechanisms underlying the efficacy and safety of human neural stem cell-derived extracellular vesicles remain unclear,presenting challenges for clinical *** promote the translation of therapy based on human neural stem cell-derived extracellular vesicles from the bench to the bedside,we conducted a comprehensive preclinical study to evaluate the efficacy and safety of human neural stem cell-derived extracellular vesicles in the treatment of ischemic *** found that administration of human neural stem cell-derived extracellular vesicles to an ischemic stroke rat model reduced the volume of cerebral infarction and promoted functional recovery by alleviating neuronal *** human neural stem cell-derived extracellular vesicles reduced neuronal apoptosis by enhancing phosphorylation of phosphoinositide 3-kinase,mammalian target of rapamycin,and protein kinase B,and these effects were reversed by treatment with a phosphoinositide 3-kinase *** findings suggest that human neural stem cell-derived extracellular vesicles play a neuroprotective role in ischemic stroke through activation of phosphoinositide 3-kinase/protein kinase B/mammalian target of rapamycin signaling ***,we showed that human neural stem cell-derived extracellular vesicles have a good in vivo safety ***,human neural stem cell-derived extracellular vesicles are a promising potential agent for the treatment of ischemic stroke.

关键词： behavior exosome extracellular vesicles ischemic stroke mammalian target of rapamycin(mTOR) middle cerebral artery occlusion neural stem cells neuronal apoptosis phosphoinositide 3-kinase(PI3K) protein kinase B(AKT)

Blood diagnostic and prognostic biomarkers in amyotrophic lateral sclerosis

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Neural Regeneration Research 2025年第9期20卷 2556-2570页

作者： Yongting lv Hongfu Li Department of Neurology Second Affiliated HospitalZhejiang University School of MedicineHangzhouZhejiang ProvinceChina Department of Medical Genetics and Center for Rare disease Second Affiliated HospitalZhejiang University School of MedicineHangzhouZhejiang ProvinceChina Nanhu Brain-Computer Interface Institute HangzhouZhejiang Province

Amyotrophic lateral sclerosis is a devastating neurodegenerative disease for which the current treatment approaches remain severely *** principal pathological alterations of the disease include the selective degeneration of motor neurons in the brain,brainstem,and spinal cord,as well as abnormal protein deposition in the cytoplasm of neurons and glial *** biological markers under extensive scrutiny are predominantly located in the cerebrospinal fluid,blood,and even *** these biomarke rs,neurofilament proteins and glial fibrillary acidic protein most accurately reflect the pathologic changes in the central nervous system,while creatinine and creatine kinase mainly indicate pathological alterations in the peripheral nerves and *** light chain levels serve as an indicator of neuronal axonal injury that remain stable throughout disease progression and are a promising diagnostic and prognostic biomarker with high specificity and ***,there are challenges in using neurofilament light chain to diffe rentiate amyotrophic lateral sclerosis from other central nervous system diseases with axonal *** fibrillary acidic protein predominantly reflects the degree of neuronal demyelination and is linked to non-motor symptoms of amyotrophic lateral sclerosis such as cognitive impairment,oxygen saturation,and the glomerular filtration *** DNA-binding protein 43,a pathological protein associated with amyotrophic lateral sclerosis,is emerging as a promising biomarker,particularly with advancements in exosome-related *** is currently lacking for the value of creatinine and creatine kinase as diagnostic markers;however,they show potential in predicting disease *** the vigorous progress made in the identification of amyotrophic lateral sclerosis biomarkers in recent years,the quest for definitive diagnostic and prognostic biomarke rs remains a formidable *** review summarizes the lat

关键词： amyotrophic lateral sclerosis biomarker blood biomarkers diagnosis glial fibrillary acidic protein neurofilament light chain prognosis TAR DNA-binding protein 43

H_(2)S and NIR light-driven nanomotors induce disulfidptosis for targeted anticancer therapy by enhancing disruption of tumor metabolic symbiosis

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Chinese Chemical Letters 2025年第1期36卷 427-432页

作者： Shangqian Zhang Jiaxuan Li Xuan Hu Zelong Chen Junliang dong Chenhao Hu Shuang Chao Yinghua lv Yuxin Pei Zhichao Pei College of Chemistry&Pharmacy Northwest A&F UniversityYangling 712100China

Disulfidptosis,a novel mechanism of programmed cell death through the disruption of tumor metabolic symbiosis(TMS),has showed tremendous potential in cancer ***,the efficacy of disulfidptosis is limited by poor permeability of drugs in solid ***,hydrogen sulfide(H_(2)S)and nearinfrared(NIR)light-driven nanomotors(denoted as HGPP)have been constructed to efficiently penetrate tumors and induce *** demonstrate glutathione(GSH)-responsive release of H_(2)S,which combined with NIR light-induced photothermal effect drive HGPP movement to facilitate deep tumor *** released H_(2)S induces tumor acidosis and disrupts TMS,where disulfide accumulation following cell starvation leads to *** addition,HGPP induce hepatoma specific cellular uptake and catalyze the conversion of glucose and oxygen to produce hydrogen peroxide(H_(2)O_(2)),leading to glucose ***,this study has developed a multifunctional Janus nanomotor that provides a novel strategy for disulfidptosis-based solid tumor therapy.

关键词： H_(2)S NIR light Nanomotors Disulfidptosis Tumor metabolic symbiosis

Construction of a 12-metal Zn(Ⅱ)-Nd(Ⅲ) nanocluster for ratiometric fluorescence detection of inflammatory marker neopterin

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Journal of Rare Earths 2025年第2期43卷 270-275页

作者： Huanyin Yu Xiaoping yang Xiaoli lv Xianfeng Huang College of Chemistry and Materials Engineering Wenzhou UniversityZhejiang Key Laboratory of Carbon MaterialsKey Lab of Biohealth Materials and Chemistry of Wenzhou

A 12-metal Zn（Ⅱ）-Nd（Ⅲ） cluster 1（sizes:1.8 nm×2.0 nm×2.0 nm） was synthesized from a long-chain type Schiff base *** displays ratiometric fluorescence response to neopterin（Neo） with high selectivity and sensitivity,which can be expressed by the equation I545nm/I1060nm=A·[Neo]2+B·[Neo]+C.1 is used to quantitatively test Neo concentrations in fetal calf serum（FCS） and urine,and the recovery ranges are 98.57%-103.82% and 99.25%-103.50%,respectively,while the relative standard deviations（RSDs） are 7.89%-9.46% and 1.85%-4.16%,*** limits of detection of 1 to Neo in FCS and urine are 0.034 and 0.021 μmol/L,respectively.

关键词： Neopterin NIR luminescence Rare earths Ratiometric fluorescence detection Zn(II)-Nd(III) nanocluster

Recent progress in constructing fluorinated solid-electrolyte interphases for stable lithium metal anodes

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International Journal of Minerals,Metallurgy and Materials 2025年第2期32卷 270-291页

作者： Di Zhang Pengfei lv Wei Qin Xin He Yuanhua He Civil Aircraft Fire Science and Safety Engineering Key Laboratory of Sichuan Province College of Civil Aviation Safety EngineeringCivil Aviation Flight University of ChinaGuanghan 618307China School of Chemical Engineering Sichuan UniversityChengdu 610065China

Lithium metal batteries(LMBs)are emerging as a promising energy storage solution owing to their high energy density and specific ***,the non-uniform plating of lithium and the potential rupture of the solid-electrolyte interphase(SEI)during extended cycling use may result in dendrite growth,which can penetrate the separator and pose significant short-circuit *** a stable SEI is essential for the long-term operation of the ***-rich SEI has garnered significant attention for its ability to effectively passivate electrodes,regulate lithium deposition,and inhibit electrolyte *** the structural components and preparation methods of existing fluorinated SEI is crucial for optimizing lithium metal anode *** paper reviews the research on optimizing LiF passivation interfaces to protect lithium metal *** focuses on four types of compositions in fluorinated SEI that work synergistically to enhance SEI *** instance,combining compounds with LiF can further enhance the mechanical strength and ionic conductivity of the *** metals with LiF significantly improves electrochemical performance at the SEI/anode interface,with a necessary focus on reducing electron tunneling ***,incorporating polymers with LiF offers balanced improvements in interfacial toughness and ionic conductivity,though maintaining structural stability over long cycles remains a critical area for future *** alloys combined with LiF increase surface energy and lithium affinity,challenges such as dendrite growth and volume expansion *** summary,this paper emphasizes the crucial role of interfacial structures in LMBs and offers comprehensive guidance for future design and development efforts in battery technology.

关键词： LiF lithium metal anodes solid-electrolyte interphase interface cycling stability