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Strengthening mechanisms in carbon nanotube reinforced bioglass composites

Jing ZHANG, Chengchang JIA, Zhizhong JIA, Jillian LADEGARD, Yanhong GU, Junhui NIE

《化学科学与工程前沿（英文）》 2012年第6卷第2期页码 126-131 doi: 10.1007/s11705-012-1279-0

摘要： Carbon nanotube reinforced bioglass composites have been successfully synthesized by two comparative sintering techniques, i.e., spark plasma sintering (SPS) and conventional compaction and sinteirng. The composites show improved mechanical properties, with SPS technique substantially better than conventional compact and sintering approach. Using SPS, compared with the 45S5Bioglass matrix, the maximum flexural strength and fracture toughness increased by 159% and 105%, respectively. Enhanced strength and toughness are attributed to the interfacial bonding and bridging effects between the carbon nanotubes and bioglass powders during crack propagations.

关键词： 45S5Bioglass multi-wall carbon nanotubes biocomposite mechanical properties sintering

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Stability and dynamics of rotor system with 45° slant crack on shaft

Yanli LIN, Xiaohui SI, Fulei CHU

《机械工程前沿（英文）》 2011年第6卷第2期页码 203-213 doi: 10.1007/s11465-011-0131-4

摘要：

Crack on a shaft is one of the common damages in a rotor system. In this paper, transverse vibrations are calculated to compare the influences of transverse crack and slant crack on the rotor system. Results show that the vibration amplitude of the rotor system with a 45° slant crack on the shaft is larger than that with a transverse crack when the two types of crack have the same depth and the rotor system runs in the same condition. Stability and dynamic characteristics of the rotor system with a 45° slant crack on the shaft under torsional excitation are analyzed by considering opening and closing of the crack. It is shown that the instability of the transverse vibration of the rotor system increases with increasing difference between the bending stiffness in two main directions, and the vibration is stable when the two bending stiffness are identical. The spectrum analysis of the steady-state response reveals that the gravity and the eccentricity produce different frequency components, and when the two bending stiffness are identical, the multiple frequency components of the torsional excitation disappear. Further investigation shows that the vibration amplitudes in combined frequencies increase rapidly in transversal, torsional, and axial vibration with increasing slant crack depth. The results are helpful for the understanding the dynamic behavior of a rotor system with a slant crack on a shaft and can be used for the detection of the slant crack on a shaft.

关键词： rotor dynamics slant crack stability torsional excitation open and close

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中国航天的发展战略和重点领域

孙来燕

《中国工程科学》 2006年第8卷第10期页码 6-12

摘要：

回顾了中国航天50年来取得的成就，总结了中国航天发展的经验及存在的差距；就国际航天的发展趋势，阐述了我国航天未来的发展战略及重点发展领域。

关键词：中国航天发展战略重点领域

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Utility of transbronchial biopsy in the diagnosis of lymphangioleiomyomatosis

null

《医学前沿（英文）》 2012年第6卷第4期页码 395-405 doi: 10.1007/s11684-012-0231-5

摘要：

Pulmonary lymphangioleiomyomatosis (LAM) is a rare cystic lung disease that targets women during their reproductive years. A confident diagnosis can often be based on clinical grounds, but diagnostic certainty requires pathological analysis. Although surgical lung biopsy is considered the gold standard for obtaining tissue in patients with diffuse lung disease, it is also associated with higher morbidity and mortality than alternative, less invasive techniques. The objective of our study was to examine the utility of transbronchial biopsy in the diagnosis of LAM. We conducted two online surveys of over 1 000 LAM patients registered with the LAM Foundation who were accessible by email. Transbronchial biopsy specimens were subsequently collected and reviewed by an expert pathologist to validate the diagnosis. We found that transbronchial biopsy has a yield of approximately 60% in patients with LAM. We conclude that transbronchial biopsy may be a safe and effective method for establishing the diagnosis of LAM, obviating the need for surgical lung biopsy in more than half of LAM patients.

关键词： lymphangioleiomyomatosis lymphangiomyomatosis multicystic lung disease diffuse cystic lung disease transbronchial biopsy perivascular epithelioid cell tumor (PEComa) HMB-45

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5G成效未达预期

Mitch Leslie

《工程（英文）》 2023年第29卷第10期页码 5-7 doi: 10.1016/j.eng.2023.08.003

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基于 5G技术的教育信息化应用研究

卢向群,孙禹

《中国工程科学》 2019年第21卷第6期页码 120-128 doi: 10.15302/J-SSCAE-2019.06.020

摘要：

教育信息化日益普及，智慧学习空间不断出现，学生对学习内容的个性化、便捷化、多样化需求也日益凸显，而第五代移动通信（ 5G）技术以其大带宽、本文重点探索 5G技术的教育信息化应用，在梳理教育信息化主要特征的基础上，分析了我国教育网络面临的技术挑战，从教学、教研、教育管理三方面着手，论证提出相应的 5G应用场景，形成 5G教育信息化总体视图。面向 2035年， 5G的技术普及与应用拓展，将不断丰富教育场景的内涵，推动教育场景的变革，成为我国教育信息化创新的原生动力。

关键词：教育信息技术教育信息化 5G 技术应用场景

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5G应用下的MIMO阵列天线去耦方法综述 Review Articles

Xiao-xi ZHANG, Ai-di REN, Ying LIU

《信息与电子工程前沿（英文）》 2020年第21卷第1期页码 62-71 doi: 10.1631/FITEE.1900466

摘要：地面测试表明，自主汽化管理液氨推进系统总重1.8 kg（包含0.34 kg液氨推进剂），比冲达到100 s，系统功耗在10 W以下。

关键词： MIMO阵列；5G手机；去耦方法

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lncR-GAS5 upregulates the splicing factor to impair endothelial autophagy, leading to atherogenesis

《医学前沿（英文）》 2023年第17卷第2期页码 317-329 doi: 10.1007/s11684-022-0931-4

摘要： Long noncoding RNAs (lncRNAs) play a critical role in the regulation of atherosclerosis. Here, we investigated the role of the lncRNA growth arrest-specific 5 (lncR-GAS5) in atherogenesis. We found that the enforced expression of lncR-GAS5 contributed to the development of atherosclerosis, which presented as increased plaque size and reduced collagen content. Moreover, impaired autophagy was observed, as shown by a decreased LC3II/LC3I protein ratio and an elevated P62 level in lncR-GAS5-overexpressing human aortic endothelial cells. By contrast, lncR-GAS5 knockdown promoted autophagy. Moreover, serine/arginine-rich splicing factor 10 (SRSF10) knockdown increased the LC3II/LC3I ratio and decreased the P62 level, thus enhancing the formation of autophagic vacuoles, autolysosomes, and autophagosomes. Mechanistically, lncR-GAS5 regulated the downstream splicing factor SRSF10 to impair autophagy in the endothelium, which was reversed by the knockdown of SRSF10. Further results revealed that overexpression of the lncR-GAS5-targeted gene miR-193-5p promoted autophagy and autophagic vacuole accumulation by repressing its direct target gene, SRSF10. Notably, miR-193-5p overexpression decreased plaque size and increased collagen content. Altogether, these findings demonstrate that lncR-GAS5 partially contributes to atherogenesis and plaque instability by impairing endothelial autophagy. In conclusion, lncR-GAS5 overexpression arrested endothelial autophagy through the miR-193-5p/SRSF10 signaling pathway. Thus, miR-193-5p/SRSF10 may serve as a novel treatment target for atherosclerosis.

关键词： lncR-GAS5 miR-193-5p splicing factor SRSF10 autophagy atherogenesis

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2020普遍通信与5G技术国际会议(UC5G 2020)

会议日期： 2020年03月26日

会议地点：上海

主办单位： APISE

Boehmite-supported CuO as a catalyst for catalytic transfer hydrogenation of 5-hydroxymethylfurfural

《化学科学与工程前沿（英文）》 2023年第17卷第4期页码 415-424 doi: 10.1007/s11705-022-2225-4

摘要： 2,5-bis(hydroxymethyl)furan (BHMF) is an important monomer of polyester. Its oxygen-containing rigid ring structure and symmetrical diol functional group establish it as an alternative to petroleum-based monomer with unique advantages for the prodution of the degradable bio-based polyester materials. Herein, we prepared a boehmite-supported copper-oxide catalyst for the selective hydrogenation of 5-hydroxymethylfurfural into BHMF via catalytic transfer hydrogenation (CTH). Further, ethanol successfully replaced conventional high-pressure hydrogen as the hydrogen donor, with up to 96.9% BHMF selectivity achieved under suitable conditions. Through characterization and factor investigations, it was noted that CuO is crucial for high BHMF selectivity. Furthermore, kinetic studies revealed a higher by-product activation energy compared to that of BHMF, which explained the influence of reaction temperature on product distribution. To establish the catalyst structure-activity correlation, a possible mechanism was proposed. The copper-oxide catalyst deactivated following CTH because ethanol reduced the CuO, which consequently decreased the active sites. Finally, calcination of the catalyst in air recovered its activity. These results will have a positive impact on hydrogenation processes in the biomass industry.

关键词： biomass 5-hydroxymethylfurfural 2 5-bis(hydroxymethyl)furan transfer hydrogenation catalysis

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一场潜在的5G干扰风暴

Chris Palmer

《工程（英文）》 2019年第5卷第5期页码 815-816 doi: 10.1016/j.eng.2019.08.007

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2020年5G移动通信与信息科学国际学术会议（MCIS-5G2020）

会议日期： 2020年06月26日

会议地点：广东广州

5G综述及中国的进展 None

Shan-zhi CHEN, Shao-li KANG

《信息与电子工程前沿（英文）》 2018年第19卷第3期页码 309-321 doi: 10.1631/FITEE.1800070

摘要： 5G技术、标准和产业化从20012年开始高速发展，是全球经济新的驱动力。本文全面介绍了5G，包括愿景、要求、演进、关键技术、标准化、频谱分配、技术试验、产业化进展和5G主要贡献者。同时指出，中国企业作为5G主要技术和标准的贡献者，正处于“5G引领”过程中。最后介绍了5G最新进展和作者关于5G的再思考。

关键词： 5G；IMT-2020；关键技术；标准；现场试验

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Management innovation of Chang’e-5 project

《工程管理前沿（英文）》 2021年第8卷第4期页码 620-626 doi: 10.1007/s42524-021-0165-1

关键词： lunar exploration sample return systems engineering project management

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Sodium butyrate activates HMGCS2 to promote ketone body production through SIRT5-mediated desuccinylation

《医学前沿（英文）》 2023年第17卷第2期页码 339-351 doi: 10.1007/s11684-022-0943-0

摘要： Ketone bodies have beneficial metabolic activities, and the induction of plasma ketone bodies is a health promotion strategy. Dietary supplementation of sodium butyrate (SB) is an effective approach in the induction of plasma ketone bodies. However, the cellular and molecular mechanisms are unknown. In this study, SB was found to enhance the catalytic activity of 3-hydroxy-3-methylglutaryl-CoA synthase 2 (HMGCS2), a rate-limiting enzyme in ketogenesis, to promote ketone body production in hepatocytes. SB administrated by gavage or intraperitoneal injection significantly induced blood β-hydroxybutyrate (BHB) in mice. BHB production was induced in the primary hepatocytes by SB. Protein succinylation was altered by SB in the liver tissues with down-regulation in 58 proteins and up-regulation in 26 proteins in the proteomics analysis. However, the alteration was mostly observed in mitochondrial proteins with 41% down- and 65% up-regulation, respectively. Succinylation status of HMGCS2 protein was altered by a reduction at two sites (K221 and K358) without a change in the protein level. The SB effect was significantly reduced by a SIRT5 inhibitor and in Sirt5-KO mice. The data suggests that SB activated HMGCS2 through SIRT5-mediated desuccinylation for ketone body production by the liver. The effect was not associated with an elevation in NAD⁺/NADH ratio according to our metabolomics analysis. The data provide a novel molecular mechanism for SB activity in the induction of ketone body production.

关键词： sodium butyrate succinylation HMGCS2 ketogenesis SIRT5