5,352 results on '"Ta"'
Search Results
2. Salvage stereotactic ablative body radiotherapy after thermal ablation of primary kidney cancer.
- Author
-
Ali, Muhammad, Kwon, Young Suk, Koo, Kendrick, Bruynzeel, Anna, Pryor, David, Schep, Daniel G., Huo, Michael, Stein, Maggie, Swaminath, Anand, Hannan, Raquibul, and Siva, Shankar
- Subjects
- *
STEREOTACTIC radiotherapy , *RENAL cell carcinoma , *GLOMERULAR filtration rate , *RENAL cancer , *NEPHROTOXICOLOGY - Abstract
Objective: To evaluate the effectiveness and safety of salvage stereotactic ablative body radiotherapy (SABR) for recurrent renal cell carcinoma (RCC) after thermal ablation (TA). Materials and Methods: This study was a multi‐institutional retrospective analysis of patients with recurrent RCC following TA who received SABR between 2016 and 2020. The primary study outcome was freedom from local failure, evaluated radiographically based on Response Evaluation Criteria in Solid Tumours (RECIST) v1.1. Distant failure, cancer‐specific survival (CSS), overall survival (OS), treatment‐related toxicity and renal function changes following SABR were the secondary outcomes. The Kaplan–Meier method was used to estimate freedom from local and distant failure, CSS and OS. Results: Seventeen patients with 18 biopsy‐confirmed RCCs were included, with a median (interquartile range [IQR]) age at time of SABR of 75.2 (72.6–68.7) years, a median (IQR) tumour size of 3.5 (1.9–4.1) cm and follow‐up (reverse Kaplan–Meier method) of 3.36 (95% confidence interval [CI] 1.6–4.1) years. Six of the 17 patients had a solitary kidney. Five patients had failed repeat TA prior to SABR. The median (IQR) time from TA procedure to SABR was 3.03 (1.5–5.1) years. No patient experienced local progression, with a local control rate of 100%. Four patients, two with baseline metastatic disease, experienced distant progression. The distant progression‐free survival, CSS and OS at 3 years were 72.1% (95% CI 51.9%–100%), 92.3% (95% CI 78.9%–100%) and 82.1% (95% CI 62.1%–100%), respectively. The median (IQR) glomerular filtration rate before SABR was 58 (40–71) mL/min, and at last follow‐up, it was 48 (33–57) mL/min. No patient experienced grade 3+ toxicity or went on to develop end‐stage renal disease. Conclusion: The results showed that SABR appears to be an effective and safe salvage strategy in patients with recurrent RCC following TA. [ABSTRACT FROM AUTHOR]
- Published
- 2025
- Full Text
- View/download PDF
3. The effect of taraxerol acetate extracted from dandelion on alleviating oxidative stress responses <italic>in vitro</italic>.
- Author
-
Lu, Jiaquan, Yi, Siying, Wang, Shuna, Shang, Yafang, Yang, Shaohua, and Cui, Kai
- Subjects
- *
OXIDANT status , *OXIDATIVE stress , *LACTATE dehydrogenase , *TRANSCRIPTOMES , *EPITHELIAL cells - Abstract
AbstractOxidative stress can be alleviated by antioxidants intakes. Taraxerol acetate (TA), a natural triterpenoid extracted from dandelions, may reduce the risk of metabolic disorders by regulating oxidative stress. In the study, we investigated the effects of TA in relieving oxidative stress in murine intestinal epithelial cells using multiomics techniques. Here, we found that TA activated the antioxidant defense system. Total antioxidant capacity (T-AOC) and Catalase (CAT) activity notably increased after TA treatment. Additionally, TA treatment effectively reduced the levels of lactate dehydrogenase (LDH) and malonaldehyde (MDA) and alleviated H2O2-induced oxidative stress. Furthermore, TA induced significant changes in the levels of 30 important metabolites. Specifically, it activated the complement and coagulation cascades, NF-κB and MAPK and glycerophospholipid pathways, resulting in altered transcript levels of related genes, such as Serpinb9e, SCD2, Hspa1b, and Hspa1a. Thus, the results demonstrated that TA potentially could promote health by alleviating H2O2-induced oxidative damage and provide valuable insights for its further development. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
4. The Effects of Surface Plasma Carburization on the Microstructure and Molten Salt Corrosion Resistance of Ta.
- Author
-
Lv, Xuming, Wei, Dongbo, Huang, Xianpu, Gao, Zeyu, and Zhang, Pingze
- Subjects
CORROSION resistance ,METALLURGY ,SCANNING electron microscopy ,FUSED salts ,X-ray diffraction ,CARBURIZATION - Abstract
In order to enhance the corrosion resistance of tantalum, the double-glow plasma (DGP) metallurgy technique was used to prepare TaC coatings on the tantalum. The morphology, microstructure, and phase constituents of TaC were examined by scanning electron microscopy (SEM) and X-ray diffraction (XRD). Nano-indentation tests were used to evaluate the mechanical properties of the coatings. The specimens were immersed in NaCl-KCl molten salt at 830 °C to evaluate their corrosion resistance. The results showed that the coating prepared by the DGP technique has a thickness of approximately 5 µm, the diffusion layer has a thickness of 2.5 µm, and the nano-indentation hardness is measured to be 17.27 GPa. The high-temperature stable ceramic phase enhances the high-temperature oxidation resistance of pure tantalum (Ta), while the dense corroded surface and oxidation products improve the anti-corrosion property of TaC coatings. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
5. Investigation on double TiN/Al(Nb,Ta)2 protective layers of TiAl-Ta alloy after high-temperature oxidation.
- Author
-
Zhang, Keren, Li, Jinguang, An, Junting, Zhao, Hui, and Zhang, Xiaoyong
- Subjects
- *
OXIDE coating , *TITANIUM nitride , *ALLOYS , *HIGH temperatures , *CHEMICAL bond lengths , *TANTALUM - Abstract
The formation process of the double continuous TiN/AlNb 2 protective oxide layers of TiAl-Ta alloy after high-temperature oxidation is investigated by experiment and first-principle calculation in this study. It is found that Ta promotes the formation of a double continuous protective barrier consisting of 2.5 μm TiN/0.5–1 μm Al(Nb,Ta) 2 layers during high temperature oxidation. And the lowest energy of twenty different AlNb 2 (1 ‾ 10) /TiN(110) terminations are identified by the first-principle calculation, which is significantly influenced by the distance of Nb-N bonding. Based on this, the location of Ta is studied which is preferred to be doped at Nb position of AlNb 2 for the formation of Al(Nb,Ta) 2 phase, thereby minimizing the total energy of the system. The formation of Al(Nb,Ta) 2 phase can facilitate the precipitation of a continuous TiN layer to form a strong interface with low energy. Finally, the formation mechanism of Al(Nb,Ta) 2 (1 ‾ 10) /TiN(110) is discussed in detail. The results provide new insights into the development of oxidation-resistant TiAl alloys. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
6. Antioxidant Release Profile from Chitosan/ĸ-Carrageenan-based Polyelectrolyte Complex Films as Active Packaging: A Preliminary Study.
- Author
-
Rahmasari, Khusna Santika and Ishartono, Bayu
- Subjects
PACKAGING film ,FICK'S laws of diffusion ,ANTIOXIDANT testing ,INFRARED spectra ,PERISHABLE foods ,CARRAGEENANS ,TANNINS - Abstract
Significant efforts are necessary to prevent the spoilage of fatty acid-rich foods as a result of lipid oxidation. Active packaging is a technology that employs packaging films containing antioxidants to increase the stability of perishable foods susceptible to oxidation. This preliminary study aimed to incorporate tannic acid (TA) into a chitosan/κ-carrageenan (Chit/κ-Car)-based polyelectrolyte complex (PEC) films and evaluate their antioxidant release profile. The composition of Chit/κ-Car, glycerol (gly), and TA in PEC films were also investigated in this preliminary study as factors influencing the mechanical properties of films and the antioxidant release profile. The prepared PEC films were identified by an FTIR spectrometer and examined through a mechanical property test. The DPPH method was used to assess the antioxidant property of the Chit/κ-Car-based PEC films. The infrared spectra revealed that PEC films were formed through the interaction between ꟷNH
3 + of Chit and ꟷOSO3 ꟷ of κ-Car. Increasing the κ-Car and TA compositions in the PEC films increased the tensile strength (TS) and water absorption capacity (WAC), but decreased the elongation (E). The release profile of TA from PEC films followed the Korsmeyer-Peppas model through the Fickian diffusion mechanism with n < 0.5. The antioxidant activity test of PEC films using the 1,1-diphenyl-2-picrylhydrazyl (DPPH) method revealed high antioxidant activity with radical scavenging activity (RSA) values up to 95.04%. As a result, the Chit/κ-Car-based PEC films have the potential to be developed as active packaging. [ABSTRACT FROM AUTHOR]- Published
- 2024
- Full Text
- View/download PDF
7. Ag interlayer's influence on microstructure and mechanical properties of laser-welded Ta/304L joints.
- Author
-
Zhou, Yongqiang, Zhu, Zhengqiang, Feng, Shanshan, Mi, Dakun, Zhu, Yunming, Chen, Yanfei, Zhao, Fei, and Guo, Yukun
- Abstract
Tantalum and 304L possess unique properties for aerospace applications. Ta offers high temperature and acid/alkali resistance, while 304L is cost-effective with excellent corrosion resistance. Joining Ta and 304L optimises design, lowers costs and meets specific requirements. This study examined laser lap welding of 0.6 mm Ta and 304L with/without silver interlayer. Joint structure and properties were analysed to reveal the influence of detrimental phases, with first principles calculations for TaFe
2 and TaCr2 . Without Ag interlayer, the joint had 1857.19 N tensile shear force and 530 HV average weld zone hardness. Adding Ag reduced TaFe2 formation, improving tensile shear strength to 2100.30 N with 460 HV average hardness. First principles calculation confirmed TaCr2 's superior phase stability over TaFe2 . [ABSTRACT FROM AUTHOR]- Published
- 2024
- Full Text
- View/download PDF
8. New Loci Relating to Rice Tiller Angle Traits Discovery Through Genome-Wide Association Analysis.
- Author
-
Shi, Jubin, Gui, Jinxin, Luo, Xinyang, Yan, Yuntao, He, Xi, Zhang, Haiqing, and He, Jiwai
- Subjects
- *
LOCUS (Genetics) , *GENOME-wide association studies , *PHENOTYPIC plasticity , *HAPLOTYPES , *DISTRIBUTION (Probability theory) - Abstract
Tiller angle (TA) is one of the most important agronomic traits that directly affects plant architecture, photosynthetic efficiency, and planting density of rice. Although many quantitative trait loci (QTLs) and associated genes for TA have been identified, the detection of TA QTLs still needs attention. This study used 238 micro-core germplasm populations for genome-wide association analysis (GWAS) of the TA. The frequency distribution of TA presented continuity in 2018 and 2019, with five QTLs designated as qTA1, qTA2, qTA6, qTA9, and qTA12. These QTLs explained phenotypic variation ranging from 5.94 to 12.38%. Among them, qTA2 and qTA6 were new QTLs of TA, and only qTA1 was detected repeatedly in 2 years. Then, 253 germplasm from the 3K Rice Genome Project were used for candidate gene and haplotypes analysis; the results showed that LOC_Os01g67770, LOC_Os02g35180, and LOC_Os09g38130 were the candidate genes of qTA1, qTA2, and qTA9, respectively. These results provided insight into the genetic improvement of plant architecture in rice. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
9. Preliminary studies on ion-pair extractions of Zr, Hf, Nb, and Ta using extractants having tertiary N atom from H2SO4 and HF.
- Author
-
Yuji Sasaki, Masashi Kaneko, and Masahiko Matsumiya
- Abstract
Ion-pair extraction enables the recovery of anionic metal ions, such as pertechnetate and chlorinated rhodium ions, by protonated extractants with tertiary amino N atom in their structures. We expand this technique for other anionic species dissolved in different mineral acids. Extractions of Zr, Hf, Nb, and Ta, metal anions present in sulfuric and hydrofluoric acids (H
2 SO4 and HF), are examined. Zr and Hf in H2 SO4 , and Zr, Hf, Nb, and Ta in HF can be extracted by ion-pair extraction using NTAamide (nitrilotriacetamide), methylimino-N, N'-dioctylacetamide (MIDOA), and trioctylamine (TOA). Basic information about their extraction behavior was obtained through this study. [ABSTRACT FROM AUTHOR]- Published
- 2024
- Full Text
- View/download PDF
10. Graduate teaching assistants’ beliefs and practices regarding mentoring in the context of an online introductory biology CURE: an exploratory study
- Author
-
Karen A. Santillan, Andrea M. Rediske, and Jeffrey T. Olimpo
- Subjects
teaching assistant ,TA ,mentoring ,mentor ,course-based undergraduate research experience ,CURE ,Special aspects of education ,LC8-6691 ,Biology (General) ,QH301-705.5 - Abstract
ABSTRACT Course-based undergraduate research experiences (CUREs) have been identified as a promising approach to engage large numbers of students in discovery-based investigations in the biological sciences. As the prevalence of CUREs continues to increase nationwide, the role of graduate teaching assistants (TAs) in facilitating these courses has simultaneously grown. In addition to serving as instructors of CUREs, previous research suggests that educators—including TAs—must also adopt additional roles, including that of a mentor. However, few studies have explicitly examined CURE TAs’ beliefs and practices regarding mentorship. To address this need, we conducted an exploratory, concurrent mixed methods study to better understand TAs’ self-reported mentoring skills levels and their experiences acting as potential mentors in the context of an online introductory biology SEA-PHAGES CURE. Results indicate that TAs (N = 12) believed themselves most skilled in areas related to listening and communication, building rapport with students, and encouraging independence with respect to student research projects. Analysis of open-ended survey data further demonstrated that the overwhelming majority of TAs (n = 10) considered themselves to be mentors, citing a diversity of rationales reflective of both psychosocial and instrumental forms of mentoring support. Collectively, these outcomes contribute to a growing body of literature on the nature and level of involvement of TAs within CURE learning environments, particularly with respect to their posited role as mentors.
- Published
- 2024
- Full Text
- View/download PDF
11. Mechanism of Ta on the microstructure and properties of Fe–Mn damping alloys
- Author
-
Liu, Gui-Xiang, Zhang, Kun, Han, Chao, Shao, Xiao-Lin, Lu, Jun, Zhang, Lin, Jiang, Xiao-Song, Wu, Zi-Xuan, and Yang, Liu
- Published
- 2024
- Full Text
- View/download PDF
12. Effect of Ta on Tensile Behavior and Deformation Mechanism of a Nickel-Based Single Crystal Superalloy
- Author
-
Ge, Mingtao, Wang, Xinguang, Li, Yongmei, Tan, Zihao, Tao, Xipeng, Yang, Yanhong, Wang, Liang, Zhang, Chunhua, Zhang, Song, Zhou, Yizhou, and Sun, Xiaofeng
- Published
- 2024
- Full Text
- View/download PDF
13. Comparison of laser cladding properties of tantalum and tantalum pentoxide powders on titanium substrates.
- Author
-
Li, Yi-Ju, Hsieh, Yueh-Hung, Lin, Wei-Ting, Tran, Hong-Chuong, Huang, Jun-Wei, Kuo, Tsung-Yuan, and Chien, Chi-Sheng
- Subjects
- *
CERAMIC coating , *BIOLOGICAL interfaces , *METAL coating , *TANTALUM oxide , *SUBSTRATES (Materials science) - Abstract
Tantalum (Ta) has excellent mechanical properties, biocompatibility, and corrosion resistance. However, its application is limited by its high cost. Tantalum pentoxide (Ta2O5), a stable oxide of Ta, is a key role of Ta surface with excellent biological properties and corrosion resistance and has the advantage of a lower cost. In this study, Ta and Ta2O5 powders were pre-placed on titanium (Ti) substrates and irradiated by a diode laser to form single-layer single-pass coatings. The scanning process was performed using a range of laser powers (1000, 1500, and 2000 W) and scanning speeds (3–5, 4.5–7.5, and 6–10 mm/s). The Ta coatings showed no surface cracking. However, spherical pores were observed near the fusion line of the coating with the substrate in some samples. The porosity increased with a decreasing laser power and scanning speed. The formation of these pores was attributed mainly to the evaporation of the Ti substrate during the cladding process and the subsequent entrapment of the vapor bubbles within the coating. The Ta2O5 coatings showed almost no pores but exhibited a small number of transverse cracks on the coating surface because of the thermal expansion coefficient mismatch between the ceramic coating and the metallic substrate. For all of the coatings, the coating hardness was significantly higher than that of the substrate. The Ta2O5 coatings (580–700 HV) showed a higher hardness than the Ta coatings (350–400 HV). Moreover, the coating hardness remained approximately constant throughout the coating depth, whereas that of the Ta coatings decreased significantly with an increasing distance from the coating surface. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
14. LOX-mediated ECM mechanical stress induces Piezo1 activation in hypoxic-ischemic brain damage and identification of novel inhibitor of LOX
- Author
-
Dongya Jiang, Jing Zhao, Jie Zheng, Yingmin Zhao, Meini Le, Dani Qin, Qiong Huang, Jinyu Huang, Qingshun Zhao, Long Wang, and Xiaohua Dong
- Subjects
LOX ,HIBD ,Ferroptosis ,Piezo1 ,TA ,Medicine (General) ,R5-920 ,Biology (General) ,QH301-705.5 - Abstract
Hypoxic-ischemic encephalopathy (HIE) poses a significant challenge in neonatal medicine, often resulting in profound and lasting neurological deficits. Current therapeutic strategies for hypoxia-ischemia brain damage (HIBD) remain limited. Ferroptosis has been reported to play a crucial role in HIE and serves as a potential therapeutic target. However, the mechanisms underlying ferroptosis in HIBD remain largely unclear. In this study, we found that elevated lysyl oxidase (LOX) expression correlates closely with the severity of HIE, suggesting LOX as a potential biomarker for HIE. LOX expression levels and enzymatic activity were significantly increased in HI-induced neuronal models both in vitro and in vivo. Notably, we discovered that HI-induced brain tissue injury results in increased stiffness and observed a selective upregulation of the mechanosensitive ion channel Piezo1 in both brain tissue of HIBD and primary cortex neurons. Mechanistically, LOX increases its catalytic substrates, the Collagen I/III components, promoting extracellular matrix (ECM) remodeling and possibly mediating ECM cross-linking, which leads to increased stiffness at the site of injury and subsequent activation of the Piezo1 channel. Piezo1 senses these stiffness stimuli and then induces neuronal ferroptosis in a GPX4-dependent manner. Pharmacological inhibition of LOX or Piezo1 ameliorated brain neuronal ferroptosis and improved learning and memory impairments. Furthermore, we identified traumatic acid (TA) as a novel LOX inhibitor that effectively suppresses LOX enzymatic activity, mitigating neuronal ferroptosis and promoting synaptic plasticity. In conclusion, our findings elucidate a critical role for LOX-mediated ECM mechanical stress-induced Piezo1 activation in regulating ferroptotic cell death in HIBD. This mechanistic insight provides a basis for developing targeted therapies aimed at ameliorating neurological outcomes in neonates affected by HIBD.
- Published
- 2024
- Full Text
- View/download PDF
15. High-precision measurement of trace-level Nb, Sn, Ta, and W in rutile using electron probe microanalysis
- Author
-
Peng-Li He, Xiao-Long Huang, and Le Zhang
- Subjects
Rutile ,Trace-level Nb ,Sn ,Ta ,and W ,Mineralization ,Geology ,QE1-996.5 - Abstract
The composition of Nb, Sn, Ta, and W in rutile can serve as a highly sensitive indicator for the mineralization of these elements. This information could also be utilized to discriminate different stages of ore deposition or distinct types of deposits. Precise and accurate measurement of trace-level concentrations of these elements in rutile is imperative for such investigations, and can be effectively achieved using electron probe microanalysis (EPMA). In this study, we employed a CAMECA SX5 field emission EPMA to develop an optimal approach for precise and accurate analysis of trace-level Nb, Sn, Ta, and W in rutile. The analytical conditions include an accelerating voltage of 25 kV, a beam current of 200 nA, a beam diameter of 1 μm, optimized background positions for Nb Lα, Sn Lα, Ta Lα, and W Lα, and aggregate intensity counting with a peak counting time of 240 s for each element per spectrometer. The detection limits (3σ) for Nb, Sn, Ta, and W ranged from 22 to 53 ppm. The highest achievable spatial resolution was approximately 4.3 μm. Analytical results obtained from potential rutile standards R10 and R632 were consistent with previous studies within the errors. The precision of these results varied from 1% to 10% (1σ), excluding W in R10 and Nb and Ta in R632, which exceeds the precision achieved in previous EPMA studies. We recommend using R10 as a reference standard for analyses of trace-level Nb, Sn, and Ta, and R632 as an appropriate reference standard for Sn and W when quantifying rutile using EPMA.
- Published
- 2024
- Full Text
- View/download PDF
16. İmam Mâtürîdî’ye Göre Hurûf-ı Mukattaa ve Tevili
- Author
-
Gülhan Maden
- Subjects
tefsir ,mâtürîdî ,te’vīlātu’l-ḳur’ān ,hurûf-ı mukattaa ,müteşâbih. ,tafsir ,māturīdī ,ta ,hurūf al-muqattaa ,mutashābih. ,Philosophy. Psychology. Religion - Abstract
Kur’an’da 29 surenin başında yer alan ve isimleriyle kesik kesik okunan mukattaa harflerinin ne anlama geldiği ile ilgili Hz. Peygamber’den sahih bir haber varid olmamıştır. Dolayısıyla bu harflerin yorumlanıp yorumlanamayacağı noktasında İslam âlimleri iki farklı kanaate sahip olmuşlardır. Daha çok selef âlimlerinden oluşan ve ehl-i hadisin ağırlıklı olduğu bir gruba göre bu harfler, manasını yalnızca Allah’ın bildiği müteşâbihât kategorisinden olup bunların yorumlanması caiz değildir. Kelamcıların başını çektiği ikinci gruba göre ise Kur’an’da anlamı bilinmeyen şeylerin olması uygun değildir; dolayısıyla bu harflerin de mutlaka bir anlamı ya da fonksiyonu vardır; binaenaleyh bu konuda tevil yapmak caizdir. Bu harflerin ne anlama geldiği ile ilgili ilk dönemlerden itibaren pek çok şey söylenmiş ve bunlar hadis, tefsir ve Kur’an ilimlerine dair eserlerde kayıt altına alınmıştır. Bu makalede dirayet tefsirinin ve sünnî kelâm ekolünün kurucu isimlerinden biri kabul edilen İmam Mâtürîdî’nin (ö. 333/944), Te’vīlātu’l-Ḳur’ān adlı tefsirinde mukattaa harflerine yaklaşımı, önceki ve sonraki tefsirlerle karşılaştırmalı olarak incelenmektedir. Onun bu harflerin yorumlanması noktasındaki tavrı, daha önce yapılmış olan yorumlara yaklaşımı ve bizzat kendisinin bu harfleri nasıl algıladığı ortaya konulmaktadır. Onun mukattaa harfleri ile ilgili bazı görüşleri hiç yorum yapmadan sadece aktardığı görülmektedir ki bu tutum, söz konusu yorumlara mesafeli durduğu şeklinde yorumlanabilir. Ancak bu yorumları tenkit etmeden eserine almasını, onları en azından muhtemel gördüğü şeklinde yorumlamak da mümkündür. Müfessir bazı görüşleri ise onlara katıldığını hissettirecek birtakım açıklamalarla birlikte takdim etmektedir. Aslında o, hurûf-ı mukattaa ile ilgili aktardığı görüşlerin tamamını muhtemel görmektedir. Ancak onun bu konudaki kırmızı çizgisi, bunlar hakkında kesin konuşmaktan kaçınmaktır. Zira bunlar, hakiki manasını yalnızca Allah ve resulünün bilebileceği müteşâbihâttandır. Mâtürîdî, mukattaa harflerini müteşâbihâttan saymakla birlikte bunların teviline karşı değildir. Ancak bunlar hakkında kesin yargı anlamını taşıyan tefsire karşıdır. Zira onun sistemine göre tefsir yetkisi sadece Hz. Peygamber ve vahye tanık olmuş sahabenin hakkıdır. Hz. Peygamberden bu konuda sahih bir haber gelmediğine göre âlimler ancak bunları tevil edebilirler; yani bunların muhtemel anlamlarını ortaya koyarlar. O, bu harflerin daha çok, muhatabın dikkatini çekme fonksiyonu üzerinde durmakta ve bunlarla ilgili, Hz. Muhammed’in nübüvvetini ispat sadedinde özgün yorumlara yer vermektedir. Onun tefsirinde, başka eserlerde benzerine rastlamadığımız iki görüş yer almaktadır. Bunlardan biri, bu harflerin tefsirinin, devamındaki cümle olduğuna dair yorumdur. Mâtürîdî bunu Hasan-ı Basrî’den nakletmektedir. Ancak ne ondan önceki ne de sonraki kaynaklarda buna benzer bir yorumla karşılaşılmamıştır. Mâtürîdî’nin, Taberî ve İbn Ebî Hâtim gibi erken dönem tefsir rivayetlerini derleyen âlimlerin bile yer vermediği bu ve benzeri görüşleri aktarması, onun tefsirinin, bazı ayetler hakkında nadir karşılaşılan yorumlar için ihmal edilmemesi gereken bir kaynak olduğunu göstermektedir. Mukattaa harfleri ile ilgili Mâtürîdî’nin özgün yorumu ise bu harflerin, Hz. Muhammed’in peygamberliğini ispat sadedinde, Kur’an’da yer verilen aklî delil ve hüccetlerden ya da kıssalardan, veyahut önceki kitaplardan kinaye oluşudur. Mukattaa harfleri ile ilgili yorumları derleyen gerek klasik gerekse son dönem eserlerinde böyle bir görüşe tesadüf edilmemiştir. Bu da aslında Mâtürîdî tefsirinin tarih boyunca ne kadar ihmal edildiğinin bir göstergesidir.
- Published
- 2024
- Full Text
- View/download PDF
17. Trait anxiety and corresponding neuromarkers predict internet addiction: A longitudinal study.
- Author
-
MIAO HE, YU MAO, and JIANG QIU
- Subjects
- *
INTERNET addiction , *LIFE change events , *PSYCHOTHERAPY , *DEFAULT mode network , *CONTROL (Psychology) - Abstract
Background and Aims: The high prevalence of internet addiction (IA) has become a worldwide problem that profoundly affects people's mental health and executive function. Empirical studies have suggested trait anxiety (TA) as one of the most robust predictors of addictive behaviors. The present study investigated the neural and socio-psychological mechanisms underlying the association between TA and IA. Methods: Firstly, we tested the correlation between TA and IA. Then we investigated the longitudinal influence of TA on IA using a linear mixed effect (LME) model. Secondly, connectome-based predictive modeling (CPM) was employed to explore neuromarkers of TA, and we tested whether the identified neuromarkers of TA can predict IA. Lastly, stressful life events and default mode network (DMN) were considered as mediating variables to explore the relationship between TA and IA. Findings: A significant positive correlation between TA and IA was found and the high TA group demonstrated higher IA across time. CPM results revealed that the functional connectivity of cognitive control and emotion-regulation circuits and DMN were significantly correlated with TA. Furthermore, a significant association was found between the neuromarkers of TA and IA. Notably, the CPM results were all validated in an independent sample. The results of mediation demonstrated that stressful life events and correlated functional connectivity mediated the association between TA and IA. Conclusions: Findings of the present study facilitate a deeper understanding of the neural and socio-psychological mechanisms linking TA and IA and provide new directions for developing neural and psychological interventions. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
18. Intestinal "Piggybacking Lipoma", A Unique Lipoma Composed of Lipoma and Overlying Epithelial Lesions: A Case-control Study and Review of Literature.
- Author
-
RAMINENI, MADHURYA, ETTEL, MARK, XIAOYAN LIAO, and YANSHENG HAO
- Subjects
GASTROINTESTINAL tumors ,LIPOMA ,ADIPOSE tissue tumors ,CASE-control method ,ADENOMA - Abstract
Background/Aim: Lipomas are rare but the most common benign mesenchymal lesions of the gastrointestinal (GI) tract, composed of mature adipose cells. The "piggybacking lipoma" is formed by lipomas with overlying polypoid epithelial lesions, such as sessile serrated lesion, tubular adenoma, or hyperplastic polyp, and the literature on these lesions is limited. In this study, we systematically investigated the clinical, endoscopic, and pathologic characteristics of these unique lipomas. Patients and Methods: This is a single-institution retrospective study of gastrointestinal tract lipomas diagnosed from 2016-2021. Those with concurrent polypoid epithelial or mesenchymal lesions during the same endoscopic episode were included and reviewed in this study, and the lipomas were classified as "piggybacking lipoma" or "non-piggybacking lipoma" depending on whether the concurrent lesion was overlying the lipoma or was at a different location in the intestine. Demographic, clinical, and endoscopic data were obtained from electronic medical records. Results: A total of 100 lipomas with concurrent epithelial or mesenchymal lesions were included in this study. Among them, 21 cases were classified as "piggybacking lipoma" and 79 were classified as "non-piggybacking lipoma". Patients with piggybacking lipomas showed a female predilection, and were more likely to be symptomatic and less likely to exhibit classic endoscopic features of lipoma. Histologically, the piggybacking polyps showed overlying sessile serrated lesions (SSL) (76.2%) and tubular adenoma (TA) (19%), whereas the non-piggybacking group had differing characteristic lesions with TA (57.5%) and SSL (6.0%). Conclusion: Piggybacking lipomas are rare lipomas with overlying polypoid epithelial lesions, most commonly SSL. They present different clinical, endoscopic, and pathologic features compared to non-piggybacking lipomas. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
19. Self-Propagating High-Temperature Synthesis of Layered Composite Ti/Hf/Ta/Ni/Ceramics Materials.
- Author
-
Kamynina, O. K., Vadchenko, S. G., Kovalev, I. D., and Prokhorov, D. V.
- Subjects
- *
SELF-propagating high-temperature synthesis , *METAL foils , *CONSTRUCTION materials , *THEORY of wave motion , *HEAT resistant alloys , *CERAMIC materials , *TANTALUM , *TITANIUM powder - Abstract
This paper describes the compounds of refractory metal foils (Ti, Hf, Ta, and Ni) with ceramic layers formed as a result of combustion of reaction tapes rolled from Ti + 0.65C, Ti + 1.7B, and 5Ti + 3Si powder mixtures. Scanning electron microscopy and X-ray diffraction analysis are applied to study the microstructure, elemental composition, and phase composition of multilayer composites obtained by self-propagating high-temperature synthesis. The effect of synthesis conditions (initial temperature and applied pressure) and the initial structure of the samples on various parameters (combustion wave front propagation velocity, microstructure, phase composition, and strength properties) of the resulting layered materials is revealed. It is shown that compounds of metal foils and reaction tapes rolled from powder mixtures during combustion are ensured due to reaction diffusion, mutual impregnation, and chemical reactions occurring in the reaction tapes and on the surface of metal foils. The strength properties of the resulting materials (up to 275 MPa at 25°C and up to 72 MPa at 1100°C) are determined using a three-point loading scheme. The results of this study can contribute to the development of structural materials operating under extreme conditions. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
20. Resolució anafòrica en traducció automàtica: el cas de l’espanyol i el català
- Author
-
Sergi Alvarez-Vidal
- Subjects
traducció automàtica ,TA ,MML ,GPT ,traducció automàtica basada en regles ,traducció automàtica neuronal ,Language and Literature ,Philology. Linguistics ,P1-1091 - Abstract
En l'última dècada, la traducció automàtica (TA) ha augmentat la seva presència no només en el sector de la traducció sinó també en el conjunt de la societat, en part pels bons resultats de qualitat obtinguts per la traducció automàtica neuronal (TAN). Actualment, els models massius de llenguatge (MML) com ara GPT (Generic Pre-trained Transformer) poden generar text sobre una infinitat de temes diferents i també traduir documents tenint en compte un context més ampli. Tot i així, per a idiomes estretament relacionats, com ara l'espanyol i el català, la traducció automàtica basada en regles (TABR) s'utilitza diàriament per traduir milers de paraules. Aquest article estudia la TAN, TABR i GPT del castellà al català, dues llengües romàniques amb una estructura molt semblant en les quals els sistemes de TABR han demostrat un bon rendiment. Utilitzem un challenge test set centrat en la resolució d'anàfores, específicament els pronoms febles, un grup de pronoms que no tenen una correlació directa entre les dues llengües. Com que els models de TABR només tenen en compte la informació a nivell de frase, només estudiem les aparicions intraoracionals. L'objectiu és avaluar un fenomen sintàctic complex que ens pot ajudar a entendre quin dels tres sistemes tradueix més bé els elements contextuals. Els resultats mostren que els dos models GPT provats són els que produeixen el nombre més baix d'errors, seguit dels sistemes de TAN. Tot i així, el nombre de traduccions errònies en el millor sistema és del 47%, cosa que contrasta amb els bons resultats d'avaluació generals que s'obtenen per a aquest parell de llengües.
- Published
- 2024
- Full Text
- View/download PDF
21. Tantalum-doped tin oxide thin films using hollow cathode gas flow sputtering technology
- Author
-
Fangfang Huo, Ruslan Muydinov, Bertwin Bilgrim Otto Seibertz, Can Wang, Manuel Hartig, Nivin Alktash, Peng Gao, and Bernd Szyszka
- Subjects
SnO2 ,Gas flow sputtering (GFS) ,Ta ,O2 flow ,Transparent conductivity ,Science (General) ,Q1-390 ,Social sciences (General) ,H1-99 - Abstract
SnO2 and tantalum doped SnO2 (TTO) thin films were prepared using reactive hollow cathode gas flow sputtering (GFS) on glass substrates. An in-situ heating process under vacuum preceded the sputtering. The resistivity of the tin oxide films was reduced to a remarkable low of 2.02 × 10−3 Ω cm, with a carrier concentration of 2.55 × 1020 cm−3 and a mobility of 12.11 cm2V−1s−1. As the substrate temperature increased, the film resistivity decreased. Notably, at a substrate temperature of 270 °C, the effect of Ta doping on the film resistivity and carrier concentration was significantly stronger compared to higher temperatures. Elevating the substrate temperature and Ta doping resulted in a lower refractive index (n). This effect was consistently strong at higher temperatures, attributed to the higher film-free carrier concentration (4.54 × 1020 cm−3) compared to lower temperatures (2.35 × 1020 cm−3). The film's structure was characterized by scanning electron microscopy (SEM), X-ray diffraction (XRD) and atomic force microscope (AFM). The preferred direction of film growth was discussed. The successful and reproducible fabrication of tin oxide films underscores the advantages of gas flow sputtering (GFS) technology. GFS offers stable operating conditions across various oxygen flow levels without requiring target oxidization control, as is required in magnetron sputtering when managing gas status and film quality.
- Published
- 2024
- Full Text
- View/download PDF
22. Developing MAX phases for nuclear fusion
- Author
-
Rigby-Bell, Maxwell, Frankel, Philipp, and Haigh, Sarah
- Subjects
radiation damage ,SAED ,STEM ,HRDIC ,Proton irradiation ,Strain ,Al ,Solid solution ,Refractory alloys ,312 ,Ta ,Ti ,TEM ,Crystallography ,FIB ,Quaternary alloys ,SEM ,MAX phases ,Nuclear fusion ,Shielding ,EDS ,Materials science ,Sintering ,Armour ,Cold press ,Ceramics ,Metallo-ceramics ,Cermets ,DFT ,XRD ,High temperature pressure-less synthesis - Abstract
The search for high heat flux and radiation resistant component materials remains one of the most stubborn obstacles to the realisation of nuclear fusion as a terrestrial power source. A group of promising materials is the Mn+1AXn (MAX) phases, where 'M' is generally an early transition metal or lanthanide, 'A' is a group 13-15 element, 'X' is carbon or nitrogen, and 'n' is a positive integer. Their interesting mix of properties has led to their consideration as candidates for extreme environment applications, such as in fusion devices. However, whilst some MAX phases have shown promise in certain areas like irradiation-induced amorphisation resistance, others have shown susceptibility to issues such as corrosion and mechanical failure. Nevertheless, given the vast elemental parameter space in which MAX phases exist and the relatively sparse data available in the literature on their tolerance to fusion-relevant environments, there is great potential in the field for development towards fusion-relevant applications. This thesis demonstrates the initial stages of a rapid MAX phase development workflow for nuclear fusion applications. This is achieved via a combination of high-throughput computational predictions, high-temperature powder synthesis, advanced X-ray and electron microscopy characterisation techniques, and high energy ion radiation damage assessments. The relative thermodynamic stabilities of hundreds of potential MAX phases have been calculated using density functional theory (DFT), with the results used to guide high temperature pressure-less sintering trials of promising candidates. As such, a series of novel (Ta,Ti)3AlC2 MAX phases have been synthesised, with crystallographic and elemental characterisations from the atomic to the macroscale performed using X-ray diffraction (XRD) and a suite of high-resolution electron microscopy techniques, such as energy dispersive X-ray spectroscopy (EDS). Finally, the response of Ti3AlC2 and the newly synthesised (Ta0.25Ti0.75)3Al0.77C2 and (Ta0.38Ti0.62)Al0.81C2 MAX phases to extreme nuclear environments has been assessed using high-energy proton irradiations at a range of temperatures up to ~650 °C, with subsequent crystallographic and microstructural evolution quantified in unprecedented detail using XRD, high-resolution digital image correlation (HRDIC) and scanning electron microscopy (SEM). A comparison of the radiation damage tolerance of the three materials is given, with implications for the applicability of Ti-Ta-alloy MAX phases in future nuclear environments, as well as the suitability of proton irradiation in simulating reactor-relevant neutron radiation damage.
- Published
- 2022
23. Injectable drug-loaded thermosensitive hydrogel delivery system for protecting retina ganglion cells in traumatic optic neuropathy.
- Author
-
Wang, Lei, Jiang, Yan, Yao, Yili, Deng, Yudan, Liu, Zhiqiang, Ding, Jiangtao, Wang, Wenwen, Chen, Hao, Nan, Kaihui, and Li, Lingli
- Subjects
RETINAL ganglion cells ,DRUG delivery systems ,INTRAVITREAL injections ,TRIAMCINOLONE acetonide ,NEURODEGENERATION - Abstract
Currently, generalized therapy for traumatic optic neuropathy (TON) is lacking. Various strategies have been developed to protect and regenerate retinal ganglion cells (RGCs) after TON. Intravitreal injection of supplements has been approved as a promising approach, although serious concerns, such as low delivery efficacy and pain due to frequent injections, remain. In this study, we tested an injectable thermosensitive hydrogel drug delivery system engineered to deliver ciliary neurotrophic factor (CNTF) and triamcinolone acetonide (TA). The results of rheological studies showed that the prepared drug-loaded hydrogel possessed a suitable mechanical modulus of ∼300 Pa, consistent with that of vitreum. The hydrogel exhibited thermosensitive with sustained drug release performance. In vitro co-culture of the CNTF-loaded hydrogel system with primary RGCs also induced significant axon regeneration, with 38.5% increase in neurite length, indicating the regenerative response of the thermosensitive hydrogel drug delivery system. A Sprague-Dawley rat optic nerve crush model was constructed and applied to determine the neuroprotective and regenerative capacities of the system. The results demonstrated that a single intravitreal injection of the drug-loaded hydrogel (PLGA-PEG-PLGA + TA or PLGA-PEG-PLGA + CNTF) significantly increased RGC survival at both 14 and 28 days. The RGC survival rate was 31.05 ± 1.41% for the drug-loaded hydrogel system (the control group was 16.79 ± 1.50%) at Day 28. These findings suggest that the injectable drug-loaded thermosensitive hydrogel delivery system is a promising therapeutic tool for treating optic nerve degeneration. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
24. A Tidal Flat Adjacent to a Fringe Mangrove Forest Mitigates p CO 2 Increases and Enhances Lateral Export of Dissolved Carbon.
- Author
-
Nakamura, Wataru, Wang, Kangnian, Ono, Kenji, Endo, Toru, Watanabe, Shin, Mori, Taiki, Furukawa, Keita, Fujimoto, Kiyoshi, and Sasaki, Jun
- Subjects
MANGROVE forests ,CARBON dioxide ,TIDAL flats ,CARBON ,MANGROVE plants - Abstract
Carbon export from mangrove forests to the oceans partly acts as a sink for atmospheric CO
2 , exceeding the rate of carbon burial in mangrove soils. Primary production in ecosystems adjacent to mangroves may prevent degassing and enhance further carbon export from mangroves to the oceans. In this study, we continuously monitored carbonate chemistry parameters (pCO2 , dissolved inorganic carbon (DIC), total alkalinity (TA)) and dissolved organic carbon (DOC) in a tidal flat adjacent to a fringe mangrove forest over a spring-neap tidal cycle. Mean pCO2 during the entire period was 923 ± 318 μatm, and the export of TA, DIC, and DOC from the mangroves to the ocean was 36 ± 26 mmol m−2 d−1 , 42 ± 39 mmol m−2 d−1 , and 10 ± 9 mmol m−2 d−1 , respectively. Semi-monthly pCO2 variations in the mangrove front were controlled by the tidal level during spring tide and by photosynthesis and respiration on the tidal flat during neap tide. This means that during neap tide, photosynthesis on the tidal flat offset the increase in pCO2 caused by the porewater export from the mangrove soil. The DIC/TA export ratio in this study was 1.17 ± 0.08, which was lower than the global average of 1.41 ± 1.39, indicating that the tidal flat adjacent to the mangrove forest may act as a buffer zone to mitigate the increase in pCO2 , resulting in much of the exported DIC being stored in the ocean. [ABSTRACT FROM AUTHOR]- Published
- 2023
- Full Text
- View/download PDF
25. HAXPES reference spectra of Ta and Ta2O5 with Cr Kα excitation.
- Author
-
Zheng, Dong, Young, Christopher N., and Stickle, William F.
- Subjects
AUGERS ,TANTALUM oxide ,RADIATION - Abstract
Monochromatic Cr K
α radiation (5414.8 eV) has been used to acquire XPS and Auger data on sputtered Ta and Ta2 O5 samples. Survey data, high-resolution scans of all observed photoelectron peaks, and high-resolution scans of Auger lines are presented herein. [ABSTRACT FROM AUTHOR]- Published
- 2023
- Full Text
- View/download PDF
26. Apple Quality during Shelf-Life after Long-Term Storage and Simulated Transport.
- Author
-
Małachowska, Maria and Tomala, Kazimierz
- Subjects
HARVESTING time ,ORCHARDS ,STORAGE ,LIFE sciences ,RETAIL industry - Abstract
With the high production of apples in Poland, the priority actions include increasing their export volume. The main objective of the presented research was to maintain sufficient firmness in the apple cultivar Gala Schniga
® SchniCo Red(s) transported to distant markets immediately after harvest or after long-term storage under ULO conditions (1.2% CO2 and 1.2% O2 ). In the study conducted during the 2021/2022 storage season on apples from the experimental orchard of the Warsaw University of Life Sciences (SGGW-WULS; Warsaw-52°14′ N, 21°1′ E), the effect of the pre- and post-harvest application of 1-MCP, harvest date, and simulated transport duration on the quality of apples in target retail trading conditions was evaluated. Apples collected on a given harvest date were divided into four samples: control (without the use of 1-MCP), Harvista™-sprayed, SmartFresh™-treated, and Harvista™-sprayed + SmartFresh™-treated. Immediately after harvest and after 9 months of storage, the apples were packed in boxes and stored at 1 °C for 6 and 8 weeks (simulated transport conditions). Directly after the simulated transport and after an additional 7 and 14 days at 25 °C (handling conditions in hot countries), the following parameters were determined: firmness, SSC, TA, and ethylene production. The study noted a significant effect of the use of 1-MCP, harvest time, and simulated transport period on all tested parameters. Apples from trees sprayed with Harvista™ maintained a firmness of >55 N for 14 days of shelf-life only if they were harvested at the optimal date and transported immediately after harvest, and if their shipping lasted 6 weeks. Such firmness could be preserved after 8 weeks of the transport of SmartFresh™-treated apples harvested at the optimal date, and of Harvista™-sprayed + SmartFresh™-treated apples harvested at a delayed date. In the latter combination, apples also maintained the desired firmness after 9 months of storage + 6 weeks of transport regardless of the harvest date. [ABSTRACT FROM AUTHOR]- Published
- 2023
- Full Text
- View/download PDF
27. İ’câzu’l-Kur’ân İlminin Oluşumunda Te’vilü Müşkili’l-Kur’ân İsimli Eserin Rolü
- Author
-
Emrullah Ülgen
- Subjects
tefsir ,belâğat ,i̇’câz ,i̇’câzu’l-kur’ân ,i̇bn kuteybe ,tevilü müşkili’l-kur’ân. ,tafsīr ,arabic rhetoric ,i̇’jâz al-qur’ān ,ibn qutaybah ,ta ,Islam ,BP1-253 ,Islamic law ,KBP1-4860 - Abstract
Kur’ân-ı Kerîm’in en belirgin vasıflarından birisi, edebî ve belâğî açıdan i’câz düzeyinde ilahi bir kitap oluşudur. Kur’ân’ın i’câzıyla ilgili erken dönem çalışmaları, daha ziyade onun bu yönüyle ilgilidir. Bulunduğu dönemin genel yapısına uygun olarak İbn Kuteybe, çeşitli açılardan Kur’ân’ın bir savunusu niteliğinde olan Te’vîlü Müşkili’l-Kur’ân isimli eserinde çok sayıda âyeti Arap dilbilimi ve retoriği açısından incelemektedir. Müellifin, eserdeki asıl gayesinin Kur’ân’da çelişki ve dilsel hatalar olduğu iddialarına edebî ve belâğî açıdan cevap vermek olduğu düşünüldüğünde, eserin i’câz açısından incelenmesi önem arz etmektedir. Buradan hareketle eserde geçen konu başlıkları ve eserin sistematiği dikkate alınarak İbn Kuteybe’nin i’câzu’l-Kur’ân ilmine ne tür katkıları olduğu tespit edilmeye çalışılmaktadır. Hicrî dördüncü asırda müstakil bir ilim hüviyetini elde eden i’câzu’l-Kur’ân ilminin ilk nüvelerinin erken dönemlerden itibaren oluşmaya başladığı görülmektedir. Hicrî ikinci asırda âyetleri çeşitli açılardan araştırma konusu yapan eserlerde, Kur’ân’ın edebî i’cazıyla ilgili işaretlerin varlığı da bu tespiti desteklemektedir. Özellikle âyetleri dil bilimsel açıdan inceleyen eserlerde sistematik olmamakla birlikte, âyetler üzerinde yapılan retorik analizlerde Kur’ân’ın i’câzıyla ilgili somut bilgiler bulunmaktadır. İ’câzu’l-Kur’ân ilmi açısından henüz teşekkül süreci olarak değerlendirilebilecek bu evre, söz konusu ilme temel teşkil etmesi açısından önem arz etmektedir. Hicrî üçüncü asra gelindiğinde ise benzer durumun devam ettiği, i’câzu’l-Kur’ân’ın henüz müstakil bir ilim hüviyetini elde etmediği görülmektedir. Ancak bir önceki dönemden farklı olarak bu dönemde telif edilen eserlerde, Kur’ân’ın i’câzına temel oluşturacak edebî ve belâğî kavramlar ile bunlarla ilişkili bilgilerin biraz daha belirginleştiği ifade edilebilir. Özellikle âyetlerin edebî ve belâğî hususiyetlerini önceleyen eserler, bir sonraki asırda bağımsız olan bu ilmin gelişim sürecine kaynak teşkil etmişlerdir. Şüphesiz bunlar arasında muhteva açısından oldukça zengin olmakla birlikte daha ziyade Arap dili temelinde inşa edilen Te’vîlü Müşkili’l-Kur’ân’ın ayrı bir yeri vardır. Söz konusu eseri bu alanda öne çıkaran başlıca faktör, i’câzın gerek teorik gerekse uygulama açısından henüz başlangıç evresinde olduğu hicrî ikinci asır ile bağımsız bir ilim formuna dönüştüğü dördüncü asır arasında köprü işlevi görmesidir. Kendisinden sonra telif edilen i’câzu’l-Kur’ân’la ilgili ilk eserlerin temel kaynakları arasında yer alması da buna delalet etmektedir. Genelde erken dönem tefsir çalışmaları özelde i’câz çalışmaları açısından Te’vîlu Müşkili’l-Kur’ân’ı bulunduğu dönemde öne çıkaran başlıca faktörlerden biri, zahiren müşkil addedilen çok sayıda âyetle ilgili retorik tahlillere yer vermesidir. Bunların hatırı sayılır kısmının Kur’ân’ın edebî i’câzıyla ilgili olduğu dikkate alındığında, eserin i’câzu’l-Kur’ân ilmi açısından önemi kendiliğinden ortaya çıkmaktadır. İbn Kuteybe’ye göre, Arapçanın edebî incelikleri Kur’ân-ı Kerim’de en mükemmel bir biçimde ortaya çıkmaktadır. Bununla birlikte kendine özgü mecâz üslubuyla Arapçanın diğer dillerden üstün olduğu fikri, onun i’câz yaklaşımının diğer bir boyutunu oluşturmaktadır. Zira bu noktadan hareketle kutsal kitaplardan farklı olarak Kur’ân’ın başka bir dile tercümesini mümkün görmemektedir. Onun bu düşüncesi ayrıca, i’câz perspektifinin son derece kapsamlı olduğuna işaret etmektedir. Her ne kadar teorik izahlara çok fazla girmese de mecâz, istiâre, maklûb, hazf, ihtisâr, tekrâr, ziyâde, kinâye, ta’rîd vb. konu başlıkları altında yer verdiği örnek âyetler üzerinde yaptığı tahlillerde i’câza dair somut bilgiler görmek mümkündür.
- Published
- 2023
- Full Text
- View/download PDF
28. Fast H+-ion implantation enables precise Fermi level engineering in quantum materials
- Author
-
DePalma, Angelo
- Published
- 2024
- Full Text
- View/download PDF
29. Fluorescein isothiocyanate‐tagged boronic acid sensor‐based pH‐dependent discerning tannic acid detection.
- Author
-
Akram, Raheel, Arshad, Anila, and Saqib, Muhammad
- Subjects
- *
TANNINS , *GALLIC acid , *GLYCOLS , *FLUORESCEIN , *FLUORESCEIN isothiocyanate , *BORONIC acids , *DETECTION limit , *CHEMICAL structure , *STANDARD deviations - Abstract
Background and purpose: The distinction of tannic acid (TA) in the presence of other analogues, i.e., gallic acid (GA), dopamine (DA), glucose (Glu), and fructose (Fruc), containing vicinal diols, has long been a significant yet challenging task due to their similar chemical structures and minuscule levels. Methods: Here, the integration of 3‐aminophenyl boronic acid‐modified fluorescein isothiocyanate (3‐APBA‐FITC) for pH‐dependent ultrasensitive and selective detection of TA in wines was proposed. By performing fluorescence signal off and pH‐dependent boronate‐ester bond synthesis, the suggested probe may specifically identify TA. Results: The as‐prepared 3‐APBA‐FITC designed probe had shown ultrahigh sensitivity with a limit of detection (LOD) of 0.151 μM. Finally, in detecting TA in artificial wine with a recovery between 92.49‐93.05 % and a relative standard deviation of no more than 2.0 %, the designed strategy has been successfully applied. Conclusion: Therefore, the envisaged sensing strategy can be an interesting option for discerning detection of diols containing analytes in food products. [ABSTRACT FROM AUTHOR]
- Published
- 2023
- Full Text
- View/download PDF
30. Effect of Ta on solidification characteristics and mechanical properties of DZ411 Ni-based superalloy.
- Author
-
Peng Peng, Zi-jie Liu, Yuan-li Xu, Xu-dong Zhang, Zhi-kun Ma, and Jia-tai Wang
- Subjects
- *
HEAT resistant alloys , *DIRECTIONAL solidification , *DENDRITIC crystals , *SOLIDIFICATION - Abstract
The effects of Ta content (2.72wt.%, 3.10wt.% and 4.00wt.%) on the solidification characteristics and mechanical properties of directionally solidified DZ411 Ni-based superalloys were investigated. It is found that the content of Mo decreases with the increase of Ta in liquid phase after directional solidification, indicating the addition of Ta can reduce the element segregation in alloys. The primary and secondary dendrite arm spacings (PDAS and SDAS) of the DZ411 alloy increase with the addition of Ta, which are consistent with the models by Hunt and Wagner. The increase of PDAS and SDAS can provide enough space for the growth of tertiary dendrite arms, which hinders the growth of unfavorably oriented primary dendrites. As a result, the addition of Ta facilitates the growth of favorably oriented dendrites. More MC carbides and γ-γ' eutectics are formed in the interdendritic regions, which is attributed to the segregation of Ta in the liquid phase. Furthermore, the degree of supersaturation of W, Mo in γ matrix increases with the increase of Ta, thus, the addition of Ta promotes the formation of TCP phase. The addition of Ta also increases the microhardness in both the primary dendrite and interdendritic regions of the alloy, and the microhardness of the primary dendrite is closer to that in interdendritic regions with the increase of Ta. [ABSTRACT FROM AUTHOR]
- Published
- 2023
- Full Text
- View/download PDF
31. The high temperature oxidation and thermal shock behavior of a dense WSi2–TaSi2 coating on Ta substrate prepared by a novel two-step process.
- Author
-
Xiao, Lairong, Xiao, Yuxiang, Zhao, Xiaojun, Zhou, Xiaojun, Zhao, Gang, Zhong, Qi, Yu, Huali, Wang, Sen, Peng, Zhenwu, and Cai, Zhenyang
- Subjects
- *
THERMAL shock , *HIGH temperatures , *SURFACE coatings , *LOGNORMAL distribution , *OXIDATION - Abstract
In order to improve the oxidation resistance of the Ta substrate, a novel two-step process including molten salt electrodeposition (Na 2 WO 4 -WO 3 system) and halide activated pack cementation was adopted to prepare a WSi 2 –TaSi 2 coating on tantalum substrate. During the electrodeposition process, dense tungsten coatings were fabricated at current densities of 30 mA/cm2, 40 mA/cm2 and 50 mA/cm2. It was observed that the grain size exhibited a log-normal distribution. When the current density was 40 mA/cm2, the grain size and flattest surface of the tungsten coating reached 9.50 ± 0.23 μm and 6.792 μm, respectively. When performing the static oxidation test, the WSi 2 –TaSi 2 coating could effectively protect the Ta substrate oxidized at 1600 °C for 30 h. This is attributed to the presence of dense SiO 2 and Ta 2 O 5 , which acted as a protective layer and suppressed the further penetration of oxygen. Furthermore, due to the matching thermal expansion coefficient between each layer and the sealing ability of semi-molten SiO 2 , the four-layer SiO 2 –W 5 Si 3 –WSi 2 –Ta 5 Si 3 coating could successfully pass 721 thermal shock tests from 1600 °C to room temperature. [ABSTRACT FROM AUTHOR]
- Published
- 2023
- Full Text
- View/download PDF
32. New distributional records of fireflies (Coleoptera, Lampyridae, Luciolinae) from two Eastern States of India with notes on their biology and an updated Indian checklist
- Author
-
Srinjana Ghosh, Subhankar Sarkar, and Susanta Chakraborty
- Subjects
Asia ,distribution ,flashing firefly ,Oriental ,ta ,Biology (General) ,QH301-705.5 - Abstract
The subfamily Luciolinae Lacordaire, 1857, a group of flashing fireflies, is composed of approximately 400 described species in the world. Though the taxonomy of this group has been fairly well established in Southeast (SE) Asia and the Australopacific Region, there is scope of gathering further information regarding taxonomic knowledge on this group from India. Until now, 32 Luciolinae species from nine genera have been reported from India, which is only about 8% (32 out of 400) of the world Luciolinae fauna. With this in mind, several faunistic surveys were conducted in Odisha and West Bengal States of India to explore the firefly fauna of the two States.The faunistic surveys conducted in the Odisha and West Bengal States of India have revealed six new distributional records of Luciolinae firefly species belonging to the genera Abscondita Ballantyne, Lambkin & Fu 2013, Asymmetricata Ballantyne 2009, Pteroptyx Olivier 1902 and Sclerotia Ballantyne 2016 in the two States, earlier which were recorded from other States of India. Of the already recorded species, Abs. perplexa is recorded for the first time from both the States, whereas Abs. chinensis, Asy. ovalis and Scl. aquatilis present new records for Odisha State and Pt. malaccae and Scl. substriata for West Bengal State. The newly-recorded taxa are presented with their examined materials, diagnoses and brief biological notes. Some more distinguishing characters were added for the male genitalia of Abs. perplexa and Asy. ovalis. Further, a checklist of Luciolinae firefly species already recorded from India is also presented.
- Published
- 2023
- Full Text
- View/download PDF
33. Unprecedented fracture toughness reported in a tailored NbTaTiHf refractory medium-entropy alloy
- Author
-
Oyerinde, Jide
- Published
- 2024
- Full Text
- View/download PDF
34. Antiepileptic drugs : salivary testing of infants with breastmilk exposure and the decision-making processes of women with epilepsy regarding infant feeding
- Author
-
Hutchinson, Laura, Reid, Bernie, Callan, Bridgeen, and Sinclair, Marlene
- Subjects
AED ,Breastfeeding Theory ,Planned Behaviour ,TPB ,Thematic Analysis ,TA - Abstract
This study is presented around its "life course", broken into chapters that demonstrate the sequential progression through each phase of the study. This commences with the introductory chapter and concludes with the study conclusions and recommendations for future action. The stages will now be briefly outlined: Chapter 1: Introduction This chapter provides an overview of the epidemiology of epilepsy, the symptoms and treatment of the condition and how the condition is considered during pregnancy and breastfeeding. The chapter then discusses the benefits and statistics of breastfeeding, barriers to breastfeeding and the use of anti-epileptic drugs when breastfeeding. The chapter goes on to discuss medication information sources and decisions by healthcare professionals regarding breastfeeding and finally discusses the use of saliva as a method of therapeutic drug monitoring. Chapter 2: Literature review This chapter reviews the literature and discusses the use of saliva in therapeutic drug monitoring of infants. The chapter concludes with reference to the literature review and how it contributed to the study aim and objectives. Chapter 3: Theoretical background This chapter provides an overview of the theoretical background to the research, providing a synopsis of relevant theories and concepts including Rational Decision Making, The Health Belief Model and the Theory of Planned Behaviour that helped to guide the study. Chapter 4: Methods This chapter includes the research methodology, methods of data collection and analysis for both phases. Ethical issues concerned with the study and the rigour of the research approaches are also addressed. Chapter 5: Results and Discussions of Qualitative Data The Demographic results are discussed in relation to the research aims and objectives using the theoretical underpinning as mentioned in chapter 3. Chapter 6: Results and Discussions of Qualitative Data-Thematic Analysis The qualitative interview results are discussed in relation to the research aims and objectives using the theoretical underpinning as mentioned in chapter 3 and analysed using Thematic Analysis. Chapter 7: Results and Discussions of Quantitative Data The method development required to allow the qualitative study to progress is described in this chapter. The results of the method developed for the quantitative extraction of lamotrigine and carbamazepine from both breast milk and saliva are discussed in relation to the research aims and objectives using data analysis methods described in chapter 4. Chapter 8: Summary and Significance of the study The strengths and limitations of the research, along with its contributions to knowledge, recommendations and summary are also discussed.
- Published
- 2020
35. Ultrafast spectroscopy of photoactive nanomaterials
- Author
-
Taylor, Victoria C. A., Oliver, Tom, and Gersen, Henkjan
- Subjects
Ultrafast ,Time-resolved ,Nanomaterials ,Femtosecond ,TA ,TRIR ,2DIR ,Transient absorption ,Two-dimensional infrared ,Localised surface plasmon polaritons ,Excitons ,J-aggregates ,Formamidinium ,Perovskite ,Hybrid perovskite ,Ferroelectric ,Large polaron ,Transient absorption microscope ,Ultrafast microscopy - Abstract
Time-resolved spectroscopy is a versatile tool to investigate ultrafast dynamics. The photoinduced dynamics of photoactive nanomaterials occur over a range of timescales and can be initiated by femtosecond processes. Understanding these dynamics is paramount to inform rational design of new materials. In this thesis I detail ultrafast spectroscopic measurements of several photoactive nanomaterials. Ultrafast transient absorption (TA) was used to investigate the dynamics of localised surface plasmon polaritons on hollow gold nanoshells (HGNs) coupled with excitons in J-aggregates. I determined for the first time, a power dependence to the phonon breathing mode period of HGNs, and investigated the transient response of a novel sample of HGNs, with J-aggregates inside as well as on the outer surface, with TA. Through my pump dependent TA measurements, I was able to isolate the transient signatures associated with J-aggregate HGN hybrid system and I propose that the picosecond response is primarily due to hot electrons rather than plexcitons as has been reported for similar systems. I used two-dimensional infrared spectroscopy to directly measure 470 ± 50 fs and 2.8 ± 0.5 ps time constants associated with the reorientation of formamidinium cations in formamidinium lead iodide perovskite thin films. Molecular dynamics simulations facilitated association of these time constants with the cation agitating about an equilibrium position, with NH2 groups pointing at opposite faces of the inorganic lattice cube, and the cation undergoing 90° flips, respectively. These timescales preclude the existence of stable (anti)ferroelectric domains in formamidinium lead iodide perovskite films which had been theorised to be the source of the unusually high power conversion efficiencies observed in this material. In addition, time-resolved infrared measurements revealed a prominent vibrational transient feature arising from a vibrational Stark shift. In the final results chapter of my thesis, I describe the ultrafast transient absorption microscopy experiment that I constructed, discuss functionality tests on the apparatus, and consider the associated design principles.
- Published
- 2020
36. THE ASSESSMENT OF THE ORTHODONTIC MINI-IMPLANTS RISK OF FRACTURE – A LITERATURE REVIEW
- Author
-
Panaite Tinela, Olteanu Daniel-Nicolae, Balcoş Carina Ana-Maria, Nikolaos Karvelas, Carmen Savin, Cristian Romanec, Ionut Luchian, and Irina-Nicoleta Zetu
- Subjects
fracture ,orthodontic mini-implant ,orthodontic mini-screw ,ta ,Dentistry ,RK1-715 - Abstract
A modern method of anchorage provision, orthodontic mini-implants appear to provide a number of advantages for both complex and anchorage-demanding orthodontic cases. This review aimed to collect data about the risk of fracture of the mini-implants in orthodontics. The main topic in the mini-implant studies is addressed to the risk of fracture because of the inappropriate selection of mini-implants from the point of view of diameter, length, type of alloy, or insertion angle.
- Published
- 2022
37. The Impact of Posterior Corneal Astigmatism on Surgically Induced Astigmatism in Cataract Surgery
- Author
-
Liu W, Yang L, and Liu J
- Subjects
surgically induced astigmatism ,sia posterior corneal astigmatism ,pa keratometric astigmatism ,ka total corneal astigmatism ,ta ,Medicine (General) ,R5-920 - Abstract
Wenjie Liu,* Lichun Yang,* Jiewei Liu Cataract Department, Shanxi Eye Hospital, Taiyuan, Shanxi Province, People’s Republic of China*These authors contributed equally to this workCorrespondence: Jiewei Liu, Email jieweiliu1967@163.comPurpose: This study aimed to evaluate the changes in posterior corneal astigmatism after cataract surgery and provide a theoretical basis to accurately evaluate the total corneal astigmatism (TA) to be corrected before toric intraocular lens (IOL) implantation.Patients and Methods: Sixty-two patients (89 eyes) who underwent phacoemulsification combined with toric IOL implantation (AcrySof IQ Toric SN6AT2-T9) at Shanxi Eye Hospital between January 2017 and September 2018 were enrolled. Surgically induced astigmatism of the posterior cornea (SIAPA) was analysed using vector analysis during pentacam examination.Results: The vector variances of keratometric astigmatism (KA), TA, and posterior corneal astigmatism (PA) preoperatively and postoperatively in the “with-the-rule (WTR) astigmatism” group and “overall patient” group were statistically significant (P < 0.05). A statistically significant difference was observed between surgically induced KA (SIAKA) and surgically induced astigmatism of the total cornea (SIATA) for all patients, including those with WTR astigmatism. For all patients, SIAKA was less than SIATA by 0.05 ± 0.21 D, and for patients with WTR astigmatism, SIAKA was less than SIATA by 0.09 ± 0.22 D. For patients in the “against-the-rule (ATR) astigmatism” group, there were no statistically significant differences between SIAKA and SIATA, although SIAKA was greater than SIATA by 0.03 ± 0.18 D. When PA ≤ 0.4 D or KA ≤ 2.0 D, SIAPA can be ignored. However, when PA > 0.4 D or KA > 2.0 D, ignoring SIAPA caused by cataract surgery incision will cause SIAKA in patients with WTR astigmatism to underestimate SIATA, while SIAKA in patients with ATR astigmatism will cause an overestimation of SIATA.Conclusion: SIA on the posterior corneal astigmatism may have a significant role on more precise planning of toric IOL implantation, especially in cases with higher preoperative anterior or posterior corneal astigmatism.Keywords: surgically induced astigmatism, SIA, posterior corneal astigmatism, PA, keratometric astigmatism, KA, total corneal astigmatism, TA
- Published
- 2022
38. Frühwarnung in Zeiten von COVID-19
- Author
-
Michaela Evers-Wölk, André Uhl, and Siegfried Behrendt
- Subjects
TA ,foresight ,risk assessment ,early warning systems ,Covid-19 pandemic ,Social sciences (General) ,H1-99 ,Technology (General) ,T1-995 - Abstract
Societies are facing the challenge of increasing multiple crisis situations, such as the consequences of global climate change, armed conflicts, or pandemics. Policy makers are challenged to find appropriate answers to questions about how to deal with future threats. In the course of the COVID-19 pandemic, numerous experiences were gained with early warning systems used in this context. Based on these experiences, this article discusses how early warning in the political sphere can be improved in the future.
- Published
- 2023
- Full Text
- View/download PDF
39. Strategies to Enable Assured Access to Semiconductors for the Department of Defense
- Author
-
National Academies of Sciences, Engineering, and Medicine, Policy and Global Affairs, Division on Engineering and Physical Sciences, Board on Science, Technology, and Economic Policy, National Materials and Manufacturing Board, Committee on Global Microelectronics: Models for the Department of Defense in Semiconductor Public–Private Partnerships, National Academies of Sciences, Engineering, and Medicine, Policy and Global Affairs, Division on Engineering and Physical Sciences, Board on Science, Technology, and Economic Policy, National Materials and Manufacturing Board, and Committee on Global Microelectronics: Models for the Department of Defense in Semiconductor Public–Private Partnerships
- Subjects
- TA, T
- Abstract
Semiconductor chips power practically all electronic devices, from cellphones and vehicles to communications and defense systems essential for national security. The Department of Defense (DoD) uses a wide range of semiconductors for mission systems such as radars, sensors, and high-power-density electronics - but the U.S. is now strongly dependent on other nations for both commercial and defense semiconductor needs. At the request of Congress, this study addresses the challenges that DoD is experiencing as it engages with the global microelectronics sector and explores ways to engage with public-private partnerships to support assured production and innovation in the semiconductor industry. The recommendations of Strategies to Enable Assured Access to Semiconductors for the Department of Defense focus on long-term strategic coordination, investment in emerging technologies, leveraging of commercial advancements, and a modernization strategy that is nimble enough to incorporate emerging technologies and be responsive to global competition.
- Published
- 2024
40. Options for a National Plan for Smart Manufacturing
- Author
-
National Academies of Sciences, Engineering, and Medicine, Policy and Global Affairs, Division on Engineering and Physical Sciences, Board on Science, Technology, and Economic Policy, National Materials and Manufacturing Board, Committee on Options for a National Plan for Smart Manufacturing, National Academies of Sciences, Engineering, and Medicine, Policy and Global Affairs, Division on Engineering and Physical Sciences, Board on Science, Technology, and Economic Policy, National Materials and Manufacturing Board, and Committee on Options for a National Plan for Smart Manufacturing
- Subjects
- TS, TA, HD
- Abstract
Smart manufacturing technologies - from advanced sensors to new computing capabilities - have the potential to greatly improve the productivity, energy efficiency, and sustainability of the U.S. manufacturing sector. Successfully implementing these technologies is essential for ensuring U.S. competitiveness and providing new job opportunities for the U.S. workforce. Options for a National Plan for Smart Manufacturing explores promising technologies transforming the manufacturing sector and identifies the research and resources needed to accelerate smart manufacturing adoption industry wide. This report also identifies critical needs for education and workforce development for smart manufacturing and makes actionable recommendations to support and train the next-generation manufacturing workforce.
- Published
- 2024
41. The Current Status and Future Direction of High-Magnetic-Field Science and Technology in the United States
- Author
-
National Academies of Sciences, Engineering, and Medicine, Division on Earth and Life Studies, Division on Engineering and Physical Sciences, Nuclear and Radiation Studies Board, Board on Physics and Astronomy, National Materials and Manufacturing Board, Committee on the Current Status and Future Direction of High-Magnetic-Field Science in the United States, Phase II, National Academies of Sciences, Engineering, and Medicine, Division on Earth and Life Studies, Division on Engineering and Physical Sciences, Nuclear and Radiation Studies Board, Board on Physics and Astronomy, National Materials and Manufacturing Board, and Committee on the Current Status and Future Direction of High-Magnetic-Field Science in the United States, Phase II
- Subjects
- QC, TA, Q
- Abstract
High magnetic fields are a vital tool in many areas of science and technology that impact our everyday lives. Magnetic resonance imaging enables a wide range of medical diagnostics and research, while nuclear magnetic resonance is critical for drug discovery research and more. High magnetic fields are an essential component to many proposed fusion energy reactors and are necessary to push the boundaries towards the development of new quantum technologies and semiconductors. At the request of the National Science Foundation, the National Academies organized a study to identify scientific opportunities and key applications for high-magnetic-field science and technology for the next decade and beyond. This report explores the current state and future prospects for high-magnetic-field technologies and recommends actions to support the workforce, facilities, magnet development, and critical materials access necessary to promote U.S. innovation.
- Published
- 2024
42. Thermal analysis for improvement of mechanical properties in fused filament fabricated parts.
- Author
-
Alam, Md Aftab, Krishnanand, Patel, Abhishek, Purohit, Rajesh, and Taufik, Mohammad
- Abstract
Additive manufacturing techniques are widely used in the present manufacturing era because of their ability to manufacture intricate products. Fused filament fabrication (FFF) is one of the most commonly adopted additive manufacturing technology, which involves the extrusion of the semi-solid polymer through the nozzle to be deposited in layers to form the part. In FFF, the polymer melt being deposited, forms the bonds with the neighboring pre-deposited melt during the part fabrication. The pre-deposited melt is at the low temperature compared to the polymer melt extruding out of the nozzle; hence the heat transfer occurs due to temperature gradient by the mode of conduction and convection. The commercialization of the FFF technology in a wide range of industrial applications still seems to be constrained due to several drawbacks such as insufficient mechanical properties, poor surface quality, and low dimensional accuracy. The grade of FFF-produced products is affected by various process parameters, for example, layer thickness, build orientation, raster width, or print speed. In FFF, process parameters are optimized to improve the quality of the final printed part. The cost of post-processing is also reduced as a result of parameter optimization. In this study, the influence of the convection coefficient on bond formation was investigated, and a model for predicting bond size in terms of convection coefficient is discussed for a given set of parameters. This work also aims to study the effects of thermal properties on neck formation and the effects of neck formation on strength, surface finish, and dimensional accuracy of the printed parts. In addition, this study reveals the problems and difficulties found in previous works, potential future scope in this area has been analyzed, and new research approaches are suggested. [ABSTRACT FROM AUTHOR]
- Published
- 2023
- Full Text
- View/download PDF
43. Carbon Nanotube-Based Intumescent Flame Retardants Achieve High-Efficiency Flame Retardancy and Simultaneously Avoid Mechanical Property Loss.
- Author
-
Qu, Qi, Xu, Jin, Wang, Huanhuan, Yu, Yinrui, Dong, Qianpeng, Zhang, Xianhua, and He, Yan
- Subjects
- *
FIREPROOFING , *FIREPROOFING agents , *FIRE resistant polymers , *HEAT release rates , *IMPACT (Mechanics) - Abstract
Intumescent flame retardants (IFR) are an excellent solution to the problem of easy combustion of polymers. Still, the negative effect of the addition of flame retardants is the decline of the mechanical properties of polymers. In this context, carbon nanotubes (CNTs) are modified with tannic acid (TA) and then wrapped on the surface of ammonium polyphosphate (APP) to construct a special intumescent flame retardant structure (CTAPP). The respective advantages of the three components in the structure are explained in detail, especially the role of CNTs with high thermal conductivity in the flame retardant system. Compared with pure natural rubber (NR), the peak heat release rate (PHRR), total heat release (THR), and total smoke production (TSP) of the composites proposed with special structural flame retardants are decreased by 68.4%, 64.3%, and 49.3%, respectively, while the limiting oxygen index (LOI) increased to 28.6%. The TA-modified CNTs wrapped on the surface of APP can effectively reduce the mechanical damage caused by the flame retardant to the polymer. To sum up, the flame retardant structure of TA-modified CNTs wrapped on APP can effectively enhance the flame retardant properties of the NR matrix and reduce the negative impact on mechanics caused by adding APP flame retardant. [ABSTRACT FROM AUTHOR]
- Published
- 2023
- Full Text
- View/download PDF
44. The Effect of PEO Treatment in a Ta-Rich Electrolyte on the Surface and Corrosion Properties of Low-Carbon Steel for Potential Use as a Biomedical Material.
- Author
-
Marcuz, Nádia, Ribeiro, Rafael Parra, Rangel, Elidiane Cipriano, da Cruz, Nilson Cristino, and Correa, Diego Rafael Nespeque
- Subjects
BIOMEDICAL materials ,TANTALUM ,MILD steel ,SURFACE properties ,OXIDE coating ,HYDROPHILIC surfaces ,PROTECTIVE coatings ,STEEL corrosion - Abstract
Fe-based materials have extensive applications in the building and automobile industries due to their excellent mechanical properties and low cost. However, their biomedical employment is restricted by the corrosion propensity when in contact with bodily fluids. In this study, single-step Plasma Electrolytic Oxidation, PEO, treatment in Ta-rich electrolyte was used, for the first time, to improve the corrosion resistance of low-carbon steel SAE 1020 for possible use as device implants. The effect of the applied voltage on the chemical and phase composition, topography, wettability, roughness, and corrosion properties were addressed. The results indicated that the Fe-based oxide coatings had a rough and hydrophilic surface, increasing the Ta content with the applied potential. The phase composition of the coatings was mainly composed of hematite (Fe
2 O3 ), with the Fourier-transform Infrared Spectroscopy, FTIR, spectrums indicating the presence of some absorbed water and organic molecules. The corrosion resistance of the PEO-treated samples was better than the substrate against saline solution (0.9% NaCl) due to the Fe2 O3 growth decorated with Ta particles, especially the sample treated at 200 V. The results state that Ta-enriched Fe-based oxide coatings could significantly improve the applicability of low-carbon steel SAE 1020 as a low-cost biomaterial, particularly for medical devices. [ABSTRACT FROM AUTHOR]- Published
- 2023
- Full Text
- View/download PDF
45. Selective CO 2 Fixation to Styrene Oxide by Ta-Substitution of Lindqvist-Type [(Ta,Nb) 6 O 19 ] 8− Clusters.
- Author
-
Chudatemiya, Vorakit, Tsukada, Mio, Nagakari, Hiroki, Kikkawa, Soichi, Hirayama, Jun, Nakatani, Naoki, Yamamoto, Takafumi, and Yamazoe, Seiji
- Subjects
- *
STYRENE oxide , *CARBON dioxide , *CATALYSIS , *DENSITY functional theory , *X-ray absorption , *METAL clusters , *METALLIC oxides , *EXTENDED X-ray absorption fine structure , *TANTALUM - Abstract
Metal oxide clusters composed of group 5 metal ions, such as Nb and Ta, exhibit catalytic activities for CO2 fixation to styrene oxide (SO) due to the highly negative natural bonding charge of the terminal O atoms that could work as CO2 activation sites. In this study, tetrabutylammonium (TBA) salts of [TaxNb6−xO19]8− (TBA-TaxNb6−x, x = 0–6) were prepared and Ta-substitution effect on the catalytic properties of TBA-TaxNb6−x for CO2 fixation to SO was investigated. We found that TBA-Ta1Nb5 shows the highest styrene carbonate (SC) selectivity (95%) among TBA-TaxNb6−x, although the SO conversion monotonously increases with the incremental Ta substitution amount. The CO2 fixation to SO under various conditions and in situ X-ray absorption fine structure measurements reveal that CO2 is activated on both terminal O sites coordinated to the Ta (terminal OTa) and Nb (terminal ONb) sites, whereas the activation of SO proceeds on the terminal OTa and/or bridge O sites that are connected to Ta. Density functional theory (DFT) calculations reveal that the terminal OTa of TBA-Ta1Nb5 preferentially adsorbs CO2 compared with other ONb base sites. We conclude that the selective CO2 activation at terminal OTa of TBA-Ta1Nb5 without SO activation is a crucial factor for high SC selectivity in the CO2 fixation to SO. [ABSTRACT FROM AUTHOR]
- Published
- 2023
- Full Text
- View/download PDF
46. A scoping review of the evaluation and effectiveness of technical assistance
- Author
-
Victoria C. Scott, Zara Jillani, Adele Malpert, Jenny Kolodny-Goetz, and Abraham Wandersman
- Subjects
Technical assistance ,TA ,Technical assistance evaluation ,Technical assistance effectiveness ,Capacity building ,Scoping review ,Medicine (General) ,R5-920 - Abstract
Abstract Background Although the benefits of evidence-based practices (EBPs) for advancing community outcomes are well-recognized, challenges with the uptake of EBPs are considerable. Technical assistance (TA) is a core capacity building strategy that has been widely used to support EBP implementation and other community development and improvement efforts. Yet despite growing reliance on TA, no reviews have systematically examined the evaluation of TA across varying implementation contexts and capacity building aims. This study draws on two decades of peer-reviewed publications to summarize the evidence on the evaluation and effectiveness of TA. Methods Guided by Arksey and O’Malley’s six-stage methodological framework, we used a scoping review methodology to map research on TA evaluation. We included peer-reviewed articles published in English between 2000 and 2020. Our search involved five databases: Business Source Complete, Cumulative Index to Nursing and Allied Health Literature (CINAHL), Education Resources Information Center (ERIC), PsycInfo, and PubMed. Results A total of 125 evaluation research studies met the study criteria. Findings indicate that publications have increased over the last two decades, signaling a growth in the recognition and reporting of TA. Technical assistance is being implemented across diverse settings, often serving socially vulnerable and under-resourced populations. Most evaluation research studies involved summative evaluations, with TA outcomes mostly reported at the organizational level. Only 5% of the studies examined sustainability of TA outcomes. This review also demonstrates that there is a lack of consistent standards regarding the definition of TA and the level of reporting across relevant TA evaluation categories (e.g., cadence of contact, and directionality). Conclusions Advances in the science and practice of TA hinge on understanding what aspects of TA are effective and when, how, and for whom these aspects of TA are effective. Addressing these core questions requires (i) a standard definition for TA; (ii) more robust and rigorous evaluation research designs that involve comparison groups and assessment of direct, indirect, and longitudinal outcomes; (iii) increased use of reliable and objective TA measures; and (iv) development of reporting standards. We view this scoping review as a foundation for improving the state of the science and practice of evaluating TA.
- Published
- 2022
- Full Text
- View/download PDF
47. A novel Ta-contained TiAl alloy with excellent high temperature performance designed for powder hot isostatic pressing.
- Author
-
Zuo, Zhenbo, Hu, Rui, Li, Shaoqiang, Lai, Yunjin, Wang, Qingxiang, Luo, Xian, Qu, Zonghong, Chang, Tao, Song, Jiaming, Han, Zhiyu, Ma, Kuan, and Li, Xin
- Subjects
- *
STRAINS & stresses (Mechanics) , *HEAT treatment , *CREEP (Materials) , *ISOSTATIC pressing , *THERMAL properties - Abstract
TiAl alloys offer strong potential for replacing conventional nickel-base alloys in structural applications at high temperatures, which requires good high temperature performance. This study analyzes the creep performance and thermal exposure characteristics for a powder hot isostatic pressing (P-HIP) Ta-contained TiAl alloy. The microstructure characteristics, creep performance, and thermal exposure properties of the nearly lamellar (NL) alloy with a size of about 145 μm were investigated. The alloy remains 0.72 % fracture strain at room temperature after exposure at 750 ℃ for 1000 h. The fitting results of creep curves show that the creep stress index n is 15.82 at 750 ℃, indicating the power law creep mechanism. By reducing the interfacial energy, Ta can facilitate the formation of metastable structures and achieve refinement. The enrichment of Ta element at the lamellar edge, both observed after thermal exposure and creep, inhibits the growth of lamellae and hinders the expansion of cavities due to its low diffusion rate, improving the thermal stabilities and creep performance. The P-HIP Ta-contained TiAl alloy shows exciting high temperature performance. • A powder metallurgy Ti–48Al–3Nb–1.5Ta alloy with excellent high temperature performance is obtained with simple heat treatment process. • The mechanism of Ta for this alloy to improving the thermal stabilities and creep performance is revealed. The enrichment of Ta element at the lamellae edge has an effect of inhibiting the growth of lamellae and hindering the expansion of pores. • The fitting results of creep curves show that the creep stress index n is 15.82 at 750 ℃, indicating power law creep mechanism. • After exposure at 750 ℃ for 1000 h, the lamellae have no obvious coarsening and the material still has 0.72 % tensile fracture strain at room temperature, indicating favorable microstructure stability and mechanical performance. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
48. Effects of Ta on the high temperature creep behavior and deformation mechanism of a Ni-based single crystal superalloy.
- Author
-
Ge, Mingtao, Li, Yongmei, Wang, Xinguang, Chu, Zhaokuang, Tao, Yan, Tan, Zihao, Liu, Jide, Yang, Yanhong, Liu, Jinlai, Zhang, Chunhua, Zhang, Song, Li, Jinguo, Zhou, Yizhou, and Sun, Xiaofeng
- Subjects
- *
CREEP (Materials) , *SINGLE crystals , *HEAT resistant alloys , *DIFFUSION coefficients , *HIGH temperatures , *TANTALUM - Abstract
The effects of Ta on the high temperature creep behavior and deformation mechanism in a Ni-based single crystal (SX) superalloy were investigated at 1120 °C/137 MPa. Ta was regarded as an essential strengthening element of the γʹ phase in the alloy, and the results indicated that the increase of Ta prolonged the creep rupture life. In this work, the addition of Ta increased the volume fraction of the γʹ phase and narrowed the γ channels, making the dislocation bowing out at the primary stage of creep more difficult. As creep continued, with a lower effective diffusion coefficient of alloying elements and larger γʹ raft thickness, the alloy with 6.5 wt% Ta addition was considered to possess the lower dislocation climbing rate, which reduced the minimum creep rate of the alloys. Subsequently, it was noted that the density of superdislocations in γʹ phase was clearly reduced with the increase of Ta. This was supposed to be the elevated Ta content in the alloy, which increased the lattice misfit and led to the formation of a denser dislocation network, thereby enhancing the interfacial strengthening effect and effectively preventing the cutting of superdislocations. The Ta effect on high-temperature creep was systematically summarized in this study, which was an important guideline for further composition design and optimization of Ni-based SX superalloys. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
49. Effect of Ta on the tribological behavior of in-situ TiC/Ni composites.
- Author
-
Zhao, Yueyang, Qi, Qian, Wang, Lujie, Zhu, Yuanyang, Zheng, Kaiyue, and Qiao, Zhuhui
- Subjects
- *
FRETTING corrosion , *MECHANICAL wear , *HARDNESS , *OXIDATION , *TITANIUM carbide , *ADHESIVE wear , *TANTALUM - Abstract
The tribological behavior of TiC/Ni composites is optimized by adding Ta, due to the improved oxidation resistance and hardness. The (Ti,Ta)C particles with core-rim structure are formed, and particle size decreases from 1.03 µm to 0.75 µm by adding 8 wt% Ta, and the hardness increases from 630.43 HV to 669.13 HV. At 20 N load, the primary wear mechanism is oxidation wear and the tribological property is influenced by oxidation resistance. At 50 N load, the main wear mechanism includes abrasive, adhesive, delamination and oxidation wear, and the tribological behavior is mainly influenced by the hardness and oxidation resistance. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
50. The effect of rootstocks on the growth, yield and fruit quality of hybrid grape varieties in cold climate condition
- Author
-
Barbara Kowalczyk, Monika Bieniasz, Jan Błaszczyk, and Przemysław Banach
- Subjects
berry quality ,grape ripeness ,strength of growth ,ta ,tss ,grape size ,Agriculture (General) ,S1-972 - Abstract
Viniculture in colder countries requires the use of rootstocks adapted to the climatic and soil conditions, which influence the essential characteristics of the vine yield in terms of the physiological and morphological features. The current study was carried out in 2015-2018 in southern Poland to examine the impact of the '5BB', '125AA', '101-14M', 'SO4' and 'Börner' rootstocks on the growth, yield and fruit quality of three grape varieties: 'Seyval Blanc', 'Johanniter' and 'Solaris'. The following biometric parameters were compared: the increment in the trunk cross-sectional area, number of inflorescences on the vine, total yield, mean weight of a cluster and chemical parameters, such as the total soluble solid (TSS) content and grape titratable acidity (TA). The cluster weight of the individual varieties was also assessed in eight categories by weight (0-700 g). The results showed that 'Solaris' and 'Johanniter' grafted onto 'Börner' and 'Seyval Blanc' onto '5BB' had significantly increased trunk diameters. For the 'Solaris' cultivar, the 'Börner' rootstock increased the TSS volume by 8.2%. In the 'Seyval Blanc' cultivar, '125AA' and 'Börner' reduced the TSS content and increased the content of TA in the berries. In the 'Johanniter' cultivar, the 'Börner' rootstock led to an increase in the TSS content with a concomitant increase in the TA.
- Published
- 2022
- Full Text
- View/download PDF
Catalog
Discovery Service for Jio Institute Digital Library
For full access to our library's resources, please sign in.