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Highly Improved Creep Resistance in Polypropylene Through Thermally Reduced Graphene Oxide and Its Creep Lifetime Prediction

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Chinese Journal of Polymer Science 2024年第2期42卷 256-266,I0010页

作者： Can-Can Zhang Jun-Long Yang Ya-jiang huang Guang-Xian Li College of Polymer Science and Engineering State Key Laboratory of Polymer Materials Engineering of ChinaSichuan UniversityChengdu610065China

Polypropylene(PP) exhibits suboptimal creep resistance due to the presence of methyl groups on its main chain, leading to irregular chain segment distribution, diminished inter-chain interaction, and crystallinity. This structural feature causes chain slippage in PP under stress,significantly constraining its service lifetime. In this study, thermally reduced graphene oxide(TrGO) nanosheets were incorporated into the PP matrix, yielding a nanocomposite with exceptional creep resistance performance. Results demonstrated that at a stress of 25 MPa, a 2.0 wt% TrGO content could enhance the creep failure lifetime of PP by 21.5 times compared to neat PP. Rheology, transmission electron microscopy(TEM),and scanning electron microscopy(SEM) characterization techniques were employed to analyze the mechanism of TrGO's influence on PP's creep behavior. It was observed that when TrGO content exceeded 1.0 wt%, an effective particle network structure formed within the PP matrix. This homogeneously dispersed TrGO-formed particle network structure restricted the migration and rearrangement of PP molecular chains, enabling prolonged stress resistance without structural failure. By combining the time-strain superposition method with the critical failure strain as a criterion, generalized creep compliance curves for PP and its composites were established, facilitating the prediction of material creep failure lifetimes, with a strong agreement between experimental and predicted lifetime values. This research proposes a novel strategy aimed at developing polypropylene materials and products with enhanced long-term stability and durability, thus extending service life, reducing failure risk, and broadening their potential across various application domains.

关键词： Thermally reduced graphene oxide Polypropylene Creep failure and lifetime prediction

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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

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Highly Hydrolysis-Resistant Polyimide Fibers Prepared by Thermal Crosslinking with Inherent Carboxyl Groups

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Chinese Journal of Polymer Science 2024年第2期42卷 247-255,I0010页

Easy hydrolysis in alkaline environments limits the use of polyimide fibers in environmental protection. The hydrolysis resistance levels of polyimide fibers can be improved by crosslinking of the macromolecular chains. In this work, crosslinked polyimide fibers(CPI fibers) were produced by intrinsic carboxyl decarboxylation for the first time. The thermal stability of the polyimide fibers containing the intrinsic carboxyl groups(PIC fibers) was studied, and the temperature of the decarboxylation-crosslinking reaction was determined to be 450 ℃. The PIC fibers were hotdrawn to initiate thermal crosslinking of the carboxyl groups and molecular chain orientation at high temperature. The CPI fibers had high tensile strengths(0.72-1.46 GPa) and compressive strengths(401-604 MPa). The oriented macromolecules and chemically crosslinked structure improved the tightness of the molecular chains and endowed the CPI fibers with excellent hydrolytic resistance. The CPI-50 fiber did not dissolve in a 0.5 wt% NaOH solution during heating at 90 ℃ for 10 h, and the tensile strength retention reached 87% when treated in 0.5 wt% NaOH solutions at 90 ℃ for 1 h, providing a guarantee for its application in alkaline corrosive environments.

关键词： Polyimide Carboxyl group Crosslinking Hydrolysis-resistance

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Highly efficient room temperature phosphorescent liquid crystalline polymer optical waveguides for advanced optoelectronics

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Science China Chemistry 2024年第10期67卷 3450-3457页

作者： Jie Li Yan Guan Wei Xia Jin-Kang Chen jiang huang Yi Chen Qi Lin Er-Qiang Chen He-Lou Xie Key Laboratory of Environmentally Friendly Chemistry and Application of Ministry of Education and Key Laboratory of Advanced Functional Polymer Materials of CollegesUniversities of Hunan Province and College of ChemistryXiangtan University Beijing National Laboratory for Molecular Sciences Key Laboratory of Polymer Chemistry and Physics of Ministry of EducationCollege of Chemistry and Molecular EngineeringPeking University School of Physics and Optoelectronics Xiangtan University

Active organic optical waveguide materials(OOWMs) incorporating room temperature phosphorescence(RTP) hold significant promise for diverse applications in photonic and optoelectronic devices. Despite this potential, realizing active RTP optical waveguides with large-sized ordered structures and minimal light loss remains a formidable challenge. To address this issue, we present a groundbreaking thermoplastic active OOWM with low light loss, leveraging room temperature phosphorescent liquid crystalline polymer(LCP). This innovative material can be easily synthesized through the copolymerization of phosphorescent and liquid crystalline monomers. The resulting RTP copolymer exhibits a nematic liquid crystal phase with a phosphorescence lifetime of approximately 0.15 ms and an afterglow duration of around 1 second. Leveraging the excellent processability of LCP,we successfully produce meter-scale fibers via melt spinning. These RTP LCP fibers, characterized by a high orientation of mesogens along the fiber axis, demonstrate superior light confinement and efficient light conduction compared to unoriented samples, resulting in a low optical loss coefficient of 0.13 dB/mm. Furthermore, the thermal responsiveness of the RTP LCP optical waveguide enables its use as a photo switch. This pioneering work paves the way for the design of new OOWMs tailored for advanced photonics and optoelectronics devices.

关键词： room temperature phosphorescence liquid crystalline polymer active optical waveguide

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Microstructures and mechanical properties of laser-directed energy deposited CrCoNi medium-entropy alloy

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Rare Metals 2024年第7期43卷 3286-3300页

作者： Wen-Jie Zhao Chang-Yu Liu Peng-Cheng Che Zhi-Liang Ning Hong-Bo Fan Jian-Fei Sun Yong-jiang huang Alfonso H.W.Ngan National Key Laboratory for Precision Hot Processing of Metals Harbin Institute of TechnologyHarbin 150001China Space Environment Simulation Research Infrastructure Harbin Institute of TechnologyHarbin 150001China Department of Mechanical Engineering The University of Hong KongHong Kong 999077China

The distinctive intrinsic heat treatment(IHT)originating from cyclic reheating in the laser-directed energy deposition(LDED) has attracted growing attention in recent *** this investigation,simulations and experimental characterizations were performed to examine the impact of IHT on the micros true ture and mechanical properties of LDED-fabricated CrCoNi medium-entropy alloy(MEA).The results show that the intensity of the IHT is proportional to the utilized laser energy density(LED).As the LED increased,significant dynamic recrystallization and grain refinement occurred within the alloy due to the enhanced intensity of ***,the high LED leads to severe hot cracking within the as-built MEA,resulting in inferior *** decreasing LED,the hot cracking was effectively ***,low LED weakened the intensity of IHT and consequently inhibited kinetic conditions of dynamic recrystallization,resulting in a heterogeneous grain structure characterized by multi-scale-sized *** structure provides significant hetero-deformation-induced hardening during plastic deformation,enabling the alloy to have a sustainable work-hardening *** expect that this work will have implications in taking full advantage of the unique IHT of the LDED process to fabricate ME As with excellent metallurgical quality and mechanical performance.

关键词： Intrinsic heat treatment Laser-directed energy deposition CrCoNi MEA Dynamic recrystallization Heterogeneous grain structure

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Higher palaeoelevation in the Baoshan Basin:Implications for landscape evolution at the southeastern margin of the Tibetan Plateau

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Journal of Palaeogeography 2024年第3期13卷 563-580页

作者： Yong-jiang huang Hao-Ran Zong Shi-Tao Zhang Arata Momohara Jin-Jin Hu Lin-Bo Jia Yun-Heng Ji Zhe-Kun Zhou Key Laboratory for Plant Diversity and Biogeography of East Asia Kunming Institute of BotanyChinese Academy of SciencesKunming 650201Yunnan ProvinceChina College of Forestry Shandong Agricultural UniversityTai'an 271018Shandong ProvinceChina Faculty of Land Resource Engineering Kunming University of Science and TechnologyKunming 650093Yunnan ProvinceChina Graduate School of Horticulture Chiba UniversityChiba 271-8510Japan Key Laboratory of Tropical Forest Ecology Xishuangbanna Tropical Botanical GardenChinese Academy of SciencesMengla 666303Yunnan ProvinceChina

Surface uplift at the southeastern margin of the Tibetan Plateau has been widely studied,but more palaeoaltimetry data are required to better understand the elevation history of this geologically complex *** this study,fossil leaves of Abies(Pinaceae),a cool-temperate element,recovered from the latest Miocene-Pliocene Yangyi Formation of the southern Baoshan Basin,were used as a proxy to estimate the local *** on the regional modern altitude range(2100-4280 m)of the genus as well as regional temperature discrepancy(1.5℃)between the past and present,the palaeoelevation of the study area was calculated to be>2360 m above sea level as compared to 1670 m at *** result suggests that the southern Baoshan Basin experienced pronounced uplift prior to the time of fossil deposition,probably as a result of crustal shortening and thickening of the northern Baoshan Terrane during the *** infer that surface growth in areas south of the Dali Basin may have been greater than previously interpreted,and that a widespread plateau or plateau patches higher than 2000 m probably extended southwards into at least the Baoshan Basin by the latest *** also infer that the elevation of the southern Baoshan Basin has decreased by at least 690 m since then,in contrast to most other scenarios in which the elevation of the southeastern margin of the Tibetan Plateau has increased or remained close to modern levels since the late *** major cause of the inferred altitude decline is likely tectonic *** a transtensional graben basin,the Baoshan Basin has experienced pull-apart and base-fall movement since the late Miocene,which would reduce the altitude of its southern part located on the hanging *** erosion associated with the increased summer rainfall might also have played a role especially in reducing the local relief,although its contribution can be *** study provides one of the few palaeoelevation

关键词： Abies Lapse rate Palaeoaltimetry Surface uplift Tectonic movement Tibetan plateau

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Rheum palmatum L. and Salvia miltiorrhiza Bge. Alleviates Acute Pancreatitis by Regulating Th17 Cell Differentiation: An Integrated Network Pharmacology Analysis, Molecular Dynamics Simulation and Experimental Validation

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Chinese Journal of Integrative Medicine 2024年第5期30卷 408-420页

作者： FENG Min-chao LUO Fang huang Liang-jiang LI Kai CHEN Zu-min LI Hui YAO Chun QIN Bai-jun CHEN Guo-zhong The First Clinical Medical College Guangxi University of Traditional Chinese MedicineNanning 530000China Guangxi Key Laboratory of Molecular Biology of Traditional Chinese Medicine and Preventive Medicine Nanning 530000China Graduate School Guangxi University of Traditional Chinese MedicineNanning 530000China Department of Gastroenterology the First Affiliated Hospital of Guangxi University of Traditional Chinese MedicineNanning 530023China

Objective: To identify the core targets of Rheum palmatum L. and Salvia miltiorrhiza Bge.,(Dahuang-Danshen, DH-DS) and the mechanism underlying its therapeutic efficacy in acute pancreatitis(AP)using a network pharmacology approach and validate the findings in animal experiments. Methods: Network pharmacology analysis was used to elucidate the mechanisms underlying the therapeutic effects of DH-DS in AP. The reliability of the results was verified by molecular docking simulation and molecular dynamics ***, the results of network pharmacology enrichment analysis were verified by immunohistochemistry,Western blot analysis and real-time quantitative PCR, respectively. Results: Sixty-seven common targets of DH-DS in AP were identified and mitogen-activated protein kinase 3(MAPK3), Janus kinase 2(JAK2), signal transducer and activator of transcription 3(STAT3), protein c-Fos(FOS) were identified as core targets in the protein interaction(PPI) network analysis. Gene ontology analysis showed that cellular response to organic substance was the main functions of DH-DS in AP, and Kyoto Encyclopedia of Genes and Genomes analysis showed that the main pathway included Th17 cell differentiation. Molecular docking simulation confirmed that DH-DS binds with strong affinity to MAPK3, STAT3 and FOS. Molecular dynamics simulation revealed that FOS-isotanshinone Ⅱ and STAT3-dan-shexinkum d had good binding capacity. Animal experiments indicated that compared with the AP model group, DH-DS treatment effectively alleviated AP by inhibiting the expression of interleukin-1β, interleukin-6 and tumor necrosis factor-α, and blocking the activation of Th17 cell differentiation(P<0.01). Conclusion: DH-DS could inhibit the expression of inflammatory factors and protect pancreatic tissues,which would be functioned by regulating Th17 cell differentiation-related m RNA and protein expressions.

关键词： Rheum palmatum L. Salvia miltiorrhiza Bge. molecular docking simulation network pharmacology acute pancreatitis Th17 cell differentiation

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NLRP3 activation in macrophages promotes acute intestinal injury in neonatal necrotizing enterocolitis

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World Journal of Pediatrics 2024年第2期20卷 153-164页

作者： Bo Shi Cheng-Jie Lyu Zhen-Kai Le Hao-Sen Ji Yi Xiao Yuan-Yuan Zhang Shou-jiang huang Lin-Jun Yu Qiang Shu Jin-Fa Tou Deng-Ming Lai Department of Neonatal Surgery Children’s HospitalZhejiang University School of MedicineNational Clinical Research Center for Child HealthHangzhou 310052China Department of Pulmonology Children’s HospitalZhejiang University School of MedicineNational Clinical Research Center for Child HealthHangzhou 310052China Department of Thoracic and Cardiovascular Surgery Children’s HospitalZhejiang University School of MedicineNational Clinical Research Center for Child HealthHangzhou 310052China

Background Macrophages are involved in various immune inflammatory disease *** study aimed to investigate the role and mechanism of macrophages in regulating acute intestinal injury in neonatal necrotizing enterocolitis(NEC).Methods CD68,nucleotide-binding oligomerization domain,leucine-rich repeat,and pyrin domain-containing 3(NLRP3),cysteine aspartate-specific protease-1(caspase-1),and interleukin-1β(IL-1β)in paraffin sections of intestinal tissues from NEC and control patients were detected with immunohistochemistry,immunofluorescence,and western *** pet milk,hypoxia and cold stimulation were used to establish a mouse(wild type and Nlrp3^(-/-))model of *** mouse macrophage(RAW 264.7)and rat intestinal epithelial cell-6 lines were also cultured followed by various ***,intestinal epithelial cell injuries,and IL-1β release were *** Compared to the gut“healthy”patients,the intestinal lamina propria of NEC patients had high macrophage infiltration and high NLRP3,caspase-1,and IL-1β ***,in vivo,the survival rate of Nlrp3^(-/-)NEC mice was dramatically improved,the proportion of intestinal macrophages was reduced,and intestinal injury was decreased compared to those of wild-type NEC ***3,caspase-1,and IL-1β derived from macrophages or supernatant from cocultures of macrophages and intestinal epithelial cells also caused intestinal epithelial cell *** Macrophage activation may be essential for NEC ***3/caspase-1/IL-1β cellular signals derived from macrophages may be the underlying mechanism of NEC development,and all these may be therapeutic targets for developing treatments for NEC.

关键词： Caspase-1 Interleukin-1β Macrophage Necrotizing enterocolitis NLRP3

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Human immunodeficiency virus-associated dementia complex with positive 14-3-3 protein in cerebrospinal fluid:A case report

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World Journal of Clinical Cases 2024年第12期12卷 2065-2073页

作者： Yun-Sen He Xiao-Hong Qin Min Feng Qin-jiang huang Meng-Jun Zhang Li-Li Guo Ming-Bin Bao Ye Tao Hong-Yuan Dai Bo Wu Department of Neurosurgery Sichuan Lansheng Brain Hospital&Shanghai Lansheng Brain Hospital Investment Co.Ltd.Chengdu 610036Sichuan ProvinceChina Department of Psychiatry Sichuan Provincial Center for Mental HealthChengdu 610072Sichuan ProvinceChina Department of Geriatrics Municipal People’s Hospital in LuzhouLuzhou 646000Sichuan ProvinceChina Department of Neurosurgery Wenjiang District People’s Hospital of ChengduChengdu 611100Sichuan ProvinceChina Department of Neurosurgery Sichuan Provincial People's HospitalUniversity of Electronic Science and Technology of China ChengduChengdu 610072Sichuan ProvinceChina Department of Neurology Sichuan Provincial People’s HospitalUniversity of Electronic Science and Technology of ChinaChengdu 610072Sichuan ProvinceChina

BACKGROUND Human immunodeficiency virus(HIV)-associated dementia(HAD)is a subcortical form of dementia characterized by memory deficits and psychomotor ***,HAD often presents with symptoms similar to those of Creutzfeldt-Jakob disease(CJD),particularly in patients with acquired immune deficiency syndrome(AIDS).CASE SUMMARY We report the case of a 54-year-old male who exhibited cognitive dysfunction and secondary behavioral changes following HIV infection and suspected prion *** patient was diagnosed with HIV during hospitalization and his cerebrospinal fluid tested positive for 14-3-3 *** electroencephalogram showed a borderline-abnormal periodic triphasic wave ***-enhanced magnetic resonance imaging revealed moderate encephalatrophy and ***,symptomatic treatment and administration of amantadine were pursued for presumed CJD,but the patient’s condition continued to *** contrast,the patient’s condition improved following anti-HIV *** individual is also the only patient with this prognosis to have survived over 4 ***,the diagnosis was revised to *** In the diagnostic process of rapidly progressive dementia,it is crucial to rule out as many potential causes as possible and to consider an autopsy to diminish diagnostic *** 14-3-3 protein should not be regarded as the definitive marker for *** laboratory screening for infectious diseases is essential to enhance diagnostic precision,especially in AIDS patients with potential ***,a trial of diagnostic treatment may be considered when additional testing is not feasible.

关键词： HIV-associated dementia Cognitive dysfunction Creutzfeld-Jakob disease Rapidly progressive dementia Case report

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风冷对三元锂电池性能影响

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清华大学学报（自然科学版） 2024年第5期64卷 889-899页

作者：贺元骅张浩然黄江苏星辰中国民用航空飞行学院民航安全工程学院广汉618300

为了有效揭示风冷对飞机机载三元动力锂电池性能的影响,该文搭建了一种风速可调节的三元锂电池风冷测试平台,从热性能、电性能、材料性能3方面分析风冷对三元锂电池性能的影响。结果表明,风冷可有效降低池体温度,对电性能、材料性能均... 详细信息

为了有效揭示风冷对飞机机载三元动力锂电池性能的影响,该文搭建了一种风速可调节的三元锂电池风冷测试平台,从热性能、电性能、材料性能3方面分析风冷对三元锂电池性能的影响。结果表明,风冷可有效降低池体温度,对电性能、材料性能均有较好的保护作用。施加风冷后,池体表面温度随风速增加而逐渐下降,池体最高温度可控制在45℃内;从而有效缓解正极的形貌结构破坏,同时抑制正极的活性物质损失和活性锂损失;进一步使电阻增加得到有效抑制,在同样循环次数下容量衰减率显著低于无风冷情况,电池的循环寿命延长近一倍。研究结果对机载三元动力锂电池风冷系统建立具有指导意义。

关键词：三元锂电池风冷热性能电性能材料性能

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