Irradiation

辐照
  • 文章类型: Journal Article
    含有氦的金属和合金的研究在核能界引起了极大的关注。然而,对注入氦气的块状合金的力学行为研究有限。这项研究研究了在一致的中子剂量下,通过硼含量控制氦气剂量,研究了几种注入氦气的Al-硼合金的机械性能。结果表明,对于氦剂量3.08×1019/cm3和6.84×1019/cm3,HemVn可能分别为强度贡献约8.4-15MPa和16.8-23MPa,而中子-铝反应引起的晶格损伤对强度的贡献为24~27兆帕。随后的退火导致氦气泡的形成,导致与HemVn相比略高的强化效果。此外,合金的加工硬化行为可以用Voce模型来解释,从7xxx合金中氦气泡和纳米沉淀物之间的相似性中汲取灵感。这些发现为核能界提供了见解。
    The study of metals and alloys containing helium has garnered significant attention within the nuclear energy community. However, there is limited research on the mechanical behavior of bulk alloys implanted with helium. This study investigates the mechanical properties of several Al-Boron alloys implanted with helium using controlled manipulation of helium doses via boron content under a consistent neutron dose. Results show that HemVn may contribute to strength by approximately 8.4-15 MPa and 16.8-23 MPa for helium doses 3.08 × 1019/cm3 and 6.84 × 1019/cm3, respectively, while lattice damages due to neutron-aluminum reaction contribute to strength by 24∼27 MPa. Subsequent annealing leads to the formation of helium bubbles, resulting in a slightly higher strengthening effect compared to HemVn. Additionally, the work hardening behavior of the alloys can be explained by the Voce model, drawing inspiration from the resemblance between helium bubbles and nanoprecipitates in 7xxx alloys. These findings provide insights to the nuclear energy community.
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  • 文章类型: Journal Article
    辐照对肉成分包括水的影响,蛋白质,脂质是多方面的。辐照导致水分子分解,导致自由基的形成,可以对肉类品质和储存产生积极和消极的影响。尽管辐射通过破坏微生物DNA和细胞膜减少了微生物的数量并延长了肉的保质期,它还可以加速脂质和蛋白质的氧化,特别是含硫氨基酸和不饱和脂肪酸。关于蛋白质,照射影响肌原纤维和肌浆蛋白。肌原纤维蛋白,如肌动蛋白和肌球蛋白,可以进行解聚和碎裂,从而改变蛋白质的溶解度和结构。肌浆蛋白,包括肌红蛋白,经历结构变化,可以改变肉的颜色。胶原蛋白,这对肉的韧性至关重要,由于辐射诱导的降解,溶解度会增加。脂质含量和组成也受辐射的影响,不饱和脂肪酸特别容易被氧化。该过程可导致脂质质量的变化和异味的产生。然而,辐照对脂质氧化的影响可能因辐照剂量和包装方法等因素而异。总之,虽然辐照可以产生有益的效果,例如减少微生物和延长保质期,它还可能导致肉类特性的变化,需要仔细管理以保持质量和消费者的可接受性。
    The effects of irradiation on meat constituents including water, proteins, and lipids are multifaceted. Irradiation leads to the decomposition of water molecules, resulting in the formation of free radicals that can have both positive and negative effects on meat quality and storage. Although irradiation reduces the number of microorganisms and extends the shelf life of meat by damaging microbial DNA and cell membranes, it can also accelerate the oxidation of lipids and proteins, particularly sulfur-containing amino acids and unsaturated fatty acids. With regard to proteins, irradiation affects both myofibrillar and sarcoplasmic proteins. Myofibrillar proteins, such as actin and myosin, can undergo depolymerization and fragmentation, thereby altering protein solubility and structure. Sarcoplasmic proteins, including myoglobin, undergo structural changes that can alter meat color. Collagen, which is crucial for meat toughness, can undergo an increase in solubility owing to irradiation-induced degradation. The lipid content and composition are also influenced by irradiation, with unsaturated fatty acids being particularly vulnerable to oxidation. This process can lead to changes in the lipid quality and the production of off-odors. However, the effects of irradiation on lipid oxidation may vary depending on factors such as irradiation dose and packaging method. In summary, while irradiation can have beneficial effects, such as microbial reduction and shelf-life extension, it can also lead to changes in meat properties that need to be carefully managed to maintain quality and consumer acceptability.
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  • 文章类型: Journal Article
    先前的研究表明,术前血小板与淋巴细胞比率(PLR)和中性粒细胞与淋巴细胞比率(NLR)是多形性胶质母细胞瘤(GBM)患者的预测因素。这项研究调查了PLR和NLR在放疗之前或开始时的预后作用。
    在80例接受常规分割放疗加同步替莫唑胺切除或活检后的GBM患者中,回顾性评估了12个因素,包括PLR和NLR,包括无进展生存期(PFS)和总生存期(OS)。
    关于多变量分析,PLR≤150,Karnofsky性能评分(KPS)90-100和O6-甲基鸟嘌呤-DNA甲基转移酶启动子甲基化与PFS改善显着相关。单个病变,KPS90~100,辅助化疗与OS显著相关;PLR≤150呈明显趋势。NLR≤3在单变量分析中显示出与PFS和OS相关的趋势。
    放疗前或放疗开始时的PLR与接受GBM照射的患者的治疗结果相关,应在未来的临床试验中加以考虑。
    UNASSIGNED: Previous studies suggested pre-operative platelet-to-lymphocyte ratio (PLR) and neutrophil-to-lymphocyte ratio (NLR) to be predictive factors in patients with glioblastoma multiforme (GBM). This study investigated the prognostic role of PLR and NLR prior to or at the beginning of radiotherapy.
    UNASSIGNED: In 80 patients with GBM receiving conventionally fractionated radiotherapy plus concurrent temozolomide following resection or biopsy, 12 factors including PLR and NLR were retrospectively evaluated regarding progression-free survival (PFS) and overall survival (OS).
    UNASSIGNED: On multivariable analyses, PLR ≤150, Karnofsky performance score (KPS) 90-100, and O6-methylguanine-DNA methyltransferase promoter methylation were significantly associated with improved PFS. Single lesion, KPS 90-100, and adjuvant chemotherapy were significantly associated with OS; PLR ≤150 showed a trend. NLR ≤3 showed a trend for associations with PFS and OS on univariable analyses.
    UNASSIGNED: PLR prior to or at the beginning of radiotherapy was associated with treatment outcomes in patients irradiated for GBM and should be considered in future clinical trials.
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  • 文章类型: Journal Article
    背景:在重建手术中,局部皮瓣可能发生组织坏死或部分皮瓣丢失,特别是在先前的照射后,这在许多肿瘤实体中可能是必要的。干细胞的应用似乎有望改善皮瓣灌注,并且可能是优化皮瓣存活的可能解决方案。
    方法:20只大鼠接受双侧随机型筋膜皮瓣的采集。右侧皮瓣在手术前4周接受了20Gy电离辐射,而左皮瓣作为非照射控制。皮瓣收获后,四种不同的干细胞混合物(5×106ASC,ASC-HUVEC,MSC,MSC-HUVEC)使用1mL纤维蛋白胶作为递送载体在右和左皮瓣下施用。临床检查皮瓣大小及其坏死面积。手术两周后,HE染色和免疫组化染色CD68和ERG,以及PCR分析(白细胞介素6,HIF-1α和VEGF),被执行了。
    结果:ASCs的应用,与无细胞组相比,ASC-HUVEC和MSC导致较低数量的CD68染色的细胞。与MSC和先前未处理的细胞组相比,ASC组中Hif1α的表达更高。用MSCs和MSCs-HUVEC治疗可防止该系列中的皮瓣收缩。
    结论:ASCs的应用,MSC和ASC-HUVEC显示具有抗炎作用。用MSCs和MSCs-HUVECs治疗可以防止皮瓣的早期收缩。
    BACKGROUND: In reconstructive surgery, local flaps might develop tissue necrosis or partial flap loss especially after previous irradiation, which may be necessary in many tumor entities. The application of stem cells seems promising to improve flap perfusion and might be a possible solution to optimize flap survival.
    METHODS: Twenty rats received harvesting of bilateral random pattern fasciocutaneous flaps. The right flaps received 20 Gy ionizing radiation 4 weeks prior to the surgery, while the left flaps served as the non-irradiated control. After flap harvest, four different stem cell mixtures (5 × 106 ASC, ASC-HUVEC, MSC, MSC-HUVEC) were applied under both right and left flaps using 1 mL fibrin glue as the delivery vehicle. Flap size and its necrotic area were examined clinically. Two weeks after the surgery, HE staining and immunohistochemical staining for CD68 and ERG, as well as PCR analysis (Interleukin 6, HIF-1α and VEGF), were performed.
    RESULTS: Application of ASCs, ASCs-HUVECs and MSCs resulted in a lower number of CD68-stained cells compared to the no cell group. The expression of Hif1α was higher in the ASC group compared to those in the MSC and previously treated no cell groups. Treatment with MSCs and MSCs-HUVECs prevented shrinking of the flaps in this series.
    CONCLUSIONS: Application of ASCs, MSCs and ASCs-HUVECs was shown to have an antiinflammatory effect. Treatment with MSCs and MSCs-HUVECs can prevent early shrinking of the flaps.
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  • 文章类型: Journal Article
    胰腺导管腺癌(PDAC)是人类最致命的恶性肿瘤之一,预后极差。它主要是由多种致癌改变驱动的,在KRAS基因中观察到最高的突变频率,这是PDAC肿瘤发生和恶性进展的关键致癌驱动因素。然而,在G12C突变特异性KRAS抑制剂出现之前,KRAS几十年来一直是不可用的。尽管有这样的发展,这种直接靶向KRAS的治疗方法通常不用于PDAC患者,原因是PDAC中G12C突变的罕见存在,只有1-2%的发生病例,适度的治疗效果,导致细胞抗性的代偿途径的激活,并且不存在有效的KRASG12D或泛-KRAS抑制剂。此外,还发现通过上游和下游调节因子或效应子靶向KRAS的间接方法无效或已知会导致主要毒性。出于这个原因,需要新的和更有效的治疗策略,结合不同的治疗方式,旨在实现协同作用和最小化内在或适应性抗性机制.在这里介绍的当前工作中,具有致癌KRASG12C的胰腺癌细胞系,G12D,或野生型KRAS用特异性KRAS或SOS1/2抑制剂治疗,并通过细胞活力系统评估了伴随的MEK抑制和辐射的治疗协同作用,2D-克隆,3D-锚固独立软琼脂,和生物发光ATP测定。通过使用蛋白质印迹分析检查了潜在的病理生理机制,凋亡测定,和RAS激活测定。
    Pancreatic ductal adenocarcinoma (PDAC) is one of the deadliest of human malignancies and carries an exceptionally poor prognosis. It is mostly driven by multiple oncogenic alterations, with the highest mutation frequency being observed in the KRAS gene, which is a key oncogenic driver of tumorogenesis and malignant progression in PDAC. However, KRAS remained undruggable for decades until the emergence of G12C mutation specific KRAS inhibitors. Despite this development, this therapeutic approach to target KRAS directly is not routinely used for PDAC patients, with the reasons being the rare presence of G12C mutation in PDAC with only 1-2% of occurring cases, modest therapeutic efficacy, activation of compensatory pathways leading to cell resistance, and absence of effective KRASG12D or pan-KRAS inhibitors. Additionally, indirect approaches to targeting KRAS through upstream and downstream regulators or effectors were also found to be either ineffective or known to cause major toxicities. For this reason, new and more effective treatment strategies that combine different therapeutic modalities aiming at achieving synergism and minimizing intrinsic or adaptive resistance mechanisms are required. In the current work presented here, pancreatic cancer cell lines with oncogenic KRAS G12C, G12D, or wild-type KRAS were treated with specific KRAS or SOS1/2 inhibitors, and therapeutic synergisms with concomitant MEK inhibition and irradiation were systematically evaluated by means of cell viability, 2D-clonogenic, 3D-anchorage independent soft agar, and bioluminescent ATP assays. Underlying pathophysiological mechanisms were examined by using Western blot analyses, apoptosis assay, and RAS activation assay.
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  • 文章类型: Journal Article
    背景:类风湿性关节炎(RA)是一种主要影响关节的慢性炎症性自身免疫性疾病,然而,全身性炎症可以影响其他器官和组织。这项研究的目的是揭示昂丹司琼(O)或β-谷甾醇(BS)对炎症反应和氧化应激的改善能力,使肝脏关节外表现(EAM)复杂化,肾,肺,关节炎和关节炎照射大鼠的心脏。
    方法:这是通过将佐剂诱导的关节炎(AIA)大鼠连续每周一次暴露于全身γ射线照射(2Gray(Gy)/分数,每周一次,连续四周,总剂量高达8Gy)。关节炎和/或关节炎照射的大鼠用BS治疗(40mg/kgb.wt./天,口服)或ip给予O(2mg/kg))或未处理作为模型组。
    结果:体重变化,爪围,氧化应激指数,炎症反应生物标志物,Janus激酶-2(JAK-2)的表达,信号转导和转录激活因子3(STAT3),高迁移率组box1(HMGB1),和活化B细胞的核因子κ-轻链增强子(NF-κB),以及靶器官中的促炎和抗炎介质,除了踝关节和关节外组织的组织病理学检查。用BS或O治疗关节炎和/或关节炎照射的大鼠,可有效缓解体重增加的变化,爪子肿胀,氧化应激,炎症反应,关节和非关节组织的组织病理学退行性改变。
    结论:获得的数据表明,BS或O通过调节关节炎和关节炎照射大鼠的氧化和炎症指标来改善关节和EAM。
    BACKGROUND: Rheumatoid arthritis (RA) is a chronic inflammatory autoimmune disorder mainly affecting joints, yet the systemic inflammation can influence other organs and tissues. The objective of this study was to unravel the ameliorative capability of Ondansetron (O) or β-sitosterol (BS) against inflammatory reactions and oxidative stress that complicates Extra-articular manifestations (EAM) in liver, kidney, lung, and heart of arthritic and arthritic irradiated rats.
    METHODS: This was accomplished by exposing adjuvant-induced arthritis (AIA) rats to successive weekly fractions of total body γ-irradiation (2 Gray (Gy)/fraction once per week for four weeks, up to a total dose of 8 Gy). Arthritic and/or arthritic irradiated rats were either treated with BS (40 mg/kg b.wt. /day, orally) or O (2 mg/kg) was given ip) or were kept untreated as model groups.
    RESULTS: Body weight changes, paw circumference, oxidative stress indices, inflammatory response biomarkers, expression of Janus kinase-2 (JAK-2), Signal transducer and activator of transcription 3 (STAT3), high mobility group box1 (HMGB1), and nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB), as well as pro- and anti-inflammatory mediators in the target organs, besides histopathological examination of ankle joints and extra-articular tissues. Treatment of arthritic and/or arthritic irradiated rats with BS or O powerfully alleviated changes in body weight gain, paw swelling, oxidative stress, inflammatory reactions, and histopathological degenerative alterations in articular and non-articular tissues.
    CONCLUSIONS: The obtained data imply that BS or O improved the articular and EAM by regulating oxidative and inflammatory indices in arthritic and arthritic irradiated rats.
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  • 文章类型: Journal Article
    结合感官试验,研究了辐照对猪肉品质特性的影响,猪肉颜色,TBARS,挥发性成分,和不同的代谢物。以1kGy的剂量照射的猪肉获得了最高的感官评分,而以3和5kGy剂量照射的猪肉获得较低的感官评分,特别是关于气味。辐照使猪肉更红润,促进脂肪氧化,导致a*和TBARS值增加。辐照猪肉中的主要挥发性物质为碳氢化合物,醛类,和酒精,和己醛,庚醛,戊酸被认为是产生辐射诱导的异味的重要物质。鉴定了65种差异代谢物。l-焦谷氨酸,l-谷氨酸,l-脯氨酸,富马酸,甜菜碱,和l-山丝氨酸被认为是导致猪肉品质差异的主要物质。此外,代谢途径,如精氨酸生物合成,丙氨酸,发现天门冬氨酸和谷氨酸的代谢受辐照的影响很大。
    The effects of irradiation on pork quality characteristics were investigated by combining sensory experiments, pork color, TBARS, volatile components, and differential metabolites. Pork irradiated at a dose of 1 kGy received the highest sensory scores, whereas pork irradiated at doses of 3 and 5 kGy obtained lower sensory scores, particularly with regard to odor. Irradiation makes pork more ruddy and promotes fat oxidation, leading to increased a* and TBARS values. The main volatile substances in irradiated pork were hydrocarbons, aldehydes, and alcohols, and hexanal, heptanal, and valeric acid were considered as important substances responsible for the generation of radiation-induced off-flavors. 65 differential metabolites were identified. l-pyroglutamic acid, l-glutamate, l-proline, fumarate acids, betaine, and l-anserine were considered as the main substances contributing to the differences in pork quality. In addition, metabolic pathways such as arginine biosynthesis, alanine, aspartate and glutamate metabolism were found to be considerably affected by irradiation.
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  • 文章类型: Journal Article
    目的:近距离放射治疗已被认为是治疗囊性颅咽管瘤(CPs)的替代选择。近距离放射治疗对CP的潜在益处尚未得到澄清。这项工作的目的是进行荟萃分析,以分析近距离放射疗法对CPs的长期疗效和不良反应。
    方法:检索相关数据库以收集CPs患者近距离放射治疗的临床试验。纳入的研究仅限于完整手稿形式的出版物,至少有5年的中位随访时间。并充分报告治疗结果和不良反应数据。Stata12.0用于数据分析。
    结果:根据纳入和排除标准,本荟萃分析共纳入6项临床试验,涉及266例CPs患者.最低平均随访时间为5年。荟萃分析的结果表明,1年,2-3年和5年无进展生存率(PFS)为75%(95CI:66-84%),62%(95CI:52-72%)和57%(95CI:22-92%),分别。在最后一次随访中,在所有纳入研究中,视力结局比基线差的患者中,少于16%.同时,对于内分泌结果,少于32%的患者比基线水平恶化。
    结论:一般来说,基于上述结果,近距离放射治疗应被视为治疗CP的良好选择.
    OBJECTIVE: Brachytherapy has been indicated as an alternative option for treating cystic craniopharyngiomas (CPs). The potential benefits of brachytherapy for CPs have not yet been clarified. The purpose of this work was to conduct a meta-analysis to analyze the long-term efficacy and adverse reactions profile of brachytherapy for CPs.
    METHODS: The relevant databases were searched to collect the clinical trials on brachytherapy in patients with CPs. Included studies were limited to publications in full manuscript form with at least 5-year median follow-up, and adequate reporting of treatment outcomes and adverse reactions data. Stata 12.0 was used for data analysis.
    RESULTS: According to the inclusion and exclusion criteria, a total of 6 clinical trials involving 266 patients with CPs were included in this meta-analysis. The minimum average follow-up was 5 years. The results of the meta-analysis showed that 1-year, 2-3 years and 5 years progression free survival rates (PFS) are 75% (95%CI: 66-84%), 62% (95%CI: 52-72%) and 57% (95%CI: 22-92%), respectively. At the last follow-up, less than 16% of patients with visual outcomes worser than baseline in all included studies. While, for endocrine outcomes, less than 32% of patients worser than baseline level.
    CONCLUSIONS: In general, based on the above results, brachytherapy should be considered as a good choice for the treatment of CP.
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  • 文章类型: Journal Article
    为了在大规模核事故的早期阶段对受伤的个体进行有效分类,确定一种易于检测的特定于辐射损伤的生物标志物至关重要。
    C57BL/6J小鼠接受全身和局部γ射线照射,以及全身X射线照射,以探讨血清sSelectin-L对辐射损伤的反应。然后,将其与对脂多糖诱导的急性感染和阿霉素诱导的DNA损伤的反应进行比较,以研究sSelectin-L对辐射的反应的特异性。此外,在鼻咽癌患者放疗前后的血清样本中进一步评估.在患有急性放射综合征的小鼠中进行了使用氨磷汀或骨髓移植的模拟抢救实验,以确定建立sSelectin-L作为预后标志物的潜力。使用ELISA方法动态测量sSelectin-L的水平。
    选择素-L主要在造血组织和淋巴组织中表达。小鼠sSelectin-L从照射后1天开始显示出剂量依赖性降低,并与淋巴细胞计数呈正相关。此外,sSelectin-L的水平反映了部分身体照射小鼠和鼻咽癌患者的放射损伤程度。sSelectin-L与γ或X射线的总剂量密切相关。腹膜内注射脂多糖或阿霉素的小鼠sSelectin-L水平没有显着变化。在用氨磷汀或骨髓移植治疗的急性放射综合征小鼠中,sSelectin-L比淋巴细胞计数降低更慢,恢复更快。
    我们的研究表明,sSelectin-L有可能成为对辐射事故后受伤个体进行分类的早期生物标志物,并成为成功抢救辐射受害者的预后指标。
    UNASSIGNED: It\'s crucial to identify an easily detectable biomarker that is specific to radiation injury in order to effectively classify injured individuals in the early stage in large-scale nuclear accidents.
    UNASSIGNED: C57BL/6J mice were subjected to whole-body and partial-body γ irradiation, as well as whole-body X-ray irradiation to explore the response of serum sSelectin-L to radiation injury. Then, it was compared with its response to lipopolysaccharide-induced acute infection and doxorubicin-induced DNA damage to study the specificity of sSelectin-L response to radiation. Furthermore, it was further evaluated in serum samples from nasopharyngeal carcinoma patients before and after radiotherapy. Simulated rescue experiments using Amifostine or bone marrow transplantation were conducted in mice with acute radiation syndrome to determine the potential for establishing sSelectin-L as a prognostic marker. The levels of sSelectin-L were dynamically measured using the ELISA method.
    UNASSIGNED: Selectin-L is mainly expressed in hematopoietic tissues and lymphatic tissues. Mouse sSelectin-L showed a dose-dependent decrease from 1 day after irradiation and exhibited a positive correlation with lymphocyte counts. Furthermore, the level of sSelectin-L reflected the degree of radiation injury in partial-body irradiation mice and in nasopharyngeal carcinoma patients. sSelectin-L was closely related to the total dose of γ or X ray. There was no significant change in the sSelectin-L levels in mice intraperitoneal injected with lipopolysaccharide or doxorubicin. The sSelectin-L was decreased slower and recovered faster than lymphocyte count in acute radiation syndrome mice treated with Amifostine or bone marrow transplantation.
    UNASSIGNED: Our study shows that sSelectin-L has the potential to be an early biomarker to classify injured individuals after radiation accidents, and to be a prognostic indicator of successful rescue of radiation victims.
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  • 文章类型: Journal Article
    低温下的高断裂韧性和辐射硬度可能是对用于浸渍超导磁体线圈的树脂的矛盾要求。测量了不同环氧树脂体系在室温(RT)和77K下的断裂韧性,并将它们的韧性与聚氨酯的韧性进行了比较,聚碳酸酯(PC)和聚(甲基丙烯酸甲酯)(PMMA)。在这项研究中测试的环氧树脂中,MY750系统具有最高的77K断裂韧性KIC=4.6MPa√m,与PMMA的KIC相当,这也表现出线性弹性行为和不稳定的裂纹扩展。测试的聚氨酯体系具有比环氧树脂高得多的77K韧性,接近PC的韧性,它被称为最坚韧的聚合物材料之一。CTD101K在断裂韧性方面表现最差。尽管如此,由于其良好的加工能力和相对较高的抗辐射能力,用于大型Nb3Sn线圈的浸渍。在这项研究中,CTD101K的断裂韧性通过添加聚乙二醇增韧剂AralditeDY040作为第四组分而得到改善。不同的环氧树脂体系暴露于质子和γ剂量高达38MGy,发现将DY040增韧剂添加到CTD101K系统中不会显着改变辐照引起的老化行为。添加DY040增韧剂时,未固化树脂混合物的粘度变化没有显著变化,在60°C的加工温度下,粘度保持在200cP以下超过24小时。因此,称为POLABMix的新树脂现在用于浸渍超导磁体线圈。
    High fracture toughness at cryogenic temperature and radiation hardness can be conflicting requirements for the resins for the impregnation of superconducting magnet coils. The fracture toughness of different epoxy-resin systems at room temperature (RT) and at 77 K was measured, and their toughness was compared with that determined for a polyurethane, polycarbonate (PC) and poly(methyl methacrylate) (PMMA). Among the epoxy resins tested in this study, the MY750 system has the highest 77 K fracture toughness of KIC = 4.6 MPa√m, which is comparable to the KIC of PMMA, which also exhibits linear elastic behaviour and unstable crack propagation. The polyurethane system tested has a much higher 77 K toughness than the epoxy resins, approaching the toughness of PC, which is known as one of the toughest polymer materials. CTD101K is the least performing in terms of fracture toughness. Despite this, it is used for the impregnation of large Nb3Sn coils for its good processing capabilities and relatively high radiation resistance. In this study, the fracture toughness of CTD101K was improved by adding the polyglycol flexibiliser Araldite DY040 as a fourth component. The different epoxy-resin systems were exposed to proton and gamma doses up to 38 MGy, and it was found that adding the DY040 flexibiliser to the CTD101K system did not significantly change the irradiation-induced ageing behaviour. The viscosity evolution of the uncured resin mix is not significantly changed when adding the DY040 flexibiliser, and at the processing temperature of 60 °C, the viscosity remains below 200 cP for more than 24 h. Therefore, the new resin referred to as POLAB Mix is now used for the impregnation of superconducting magnet coils.
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