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81.
S.K. Samanta S.K. Mitra T.K. Pal 《Journal of Materials Engineering and Performance》2008,17(6):908-914
The present investigation reports microstructure and high-temperature oxidation behavior of GTAW and laser weldments of 316L
stainless steel. The microstructure and oxidation behavior of composite laser weldment are found to be influenced by the welding
speed. In GTAW weldment, weld metal shows higher oxidation rate as compared to base metal of same weldment. Furthermore, the
inoculation of Ce in GTAW weld influences the microstructure and oxidation characteristics. The scale morphologies, scale
adherence, and spallation have been characterized by SEM and EDAX. 相似文献
82.
Yttrium hydroxide and aluminium hydroxide hydrogel were derived from yttrium nitrate and aluminium nitrate through hydroxy hydrogel route in which SiC particles were kept dispersed. The gel-like mass was heat treated at 900°C in ambient atmosphere followed by heat treatment at 1400°C in Ar atmosphere. The specimens were then sintered in the temperature range of 1800–1950°C in Ar atmosphere with 30 min soaking. The phases were identified by XRD analysis. Microstructure of the sintered materials were analysed by scanning electron micrograph. With this new method of preparation of powder precursors, the process of sintering was easier and almost theoretical density was achieved with moderate hardness. The mechanism of densification was postulated to be a solid-state initiated liquid phase sintering and the overall process of which was activated by the reactive species formed from hydroxy hydrogel powder precursors. 相似文献
83.
84.
Abstract Studies have been done to design an optimum composition of alkali/surfactant/polymer (ASP) slug and its application in flooding to increase the additional recovery of oil. A very low concentration of alkali and surfactant is used to achieve ultra-low interfacial tension between the trapped oil and the injection water, and polymer is used to increase the viscosity of the injection water for mobility control. Based on the experimental results of physico-chemical properties of polymer, surfactant, and alkali and their mutual interaction in solution, an ASP slug of composition SDS: 0.1 wt%, SDBS: 0.075 wt%, polyacrylamide: 2,000 ppm, and NaOH: 0.7 wt% has been recommended for flooding. Two sets of core-flooding experiments have been conducted using the designed ASP slug in a tri-axial core holder to measure the additional recovery of oil. The average additional oil recovery over conventional water flooding was found to be more than 20% of the original oil in place (OOIP). 相似文献
85.
Development of a Highly Selective,Sensitive, and Fast Response Upconversion Luminescent Platform for Hydrogen Sulfide Detection
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Juanjuan Peng Chai Lean Teoh Xiao Zeng Animesh Samanta Lu Wang Wang Xu Dongdong Su Lin Yuan Xiaogang Liu Young‐Tae Chang 《Advanced functional materials》2016,26(2):191-199
Hydrogen sulfide (H2S) has been recognized as one of most important gaseous signaling molecules mediated by a variety of physiological and pathological processes. Yet, its functions remain largely elusive due to the lack of potent monitoring methods. Hereby this issue is addressed with a powerful new platform—dye‐assembled upconversion nanoparticles (UCNPs). A series of chromophores with different absorption bands and fast responses towards H2S is combined with UCNPs and results in a library of H2S sensors with responsive emission signals ranging from the visible to the near‐infrared (NIR) region. These nanoprobes demonstrate highly selective and rapid responses to H2S in vitro and in cells. Furthermore, H2S levels in blood can be detected using the developed nanoprobes. Hence the reported H2S sensing platform can serve as a powerful diagnostic tool to research H2S functions and to investigate H2S‐related diseases. 相似文献
86.
Maria Arif Tanmoy Mondal Asifa Majeed Christopher A. Loffredo Brent E. Korba Somiranjan Ghosh 《International journal of molecular sciences》2022,23(18)
Poor glycemic control and dyslipidemia are hallmarks of type 2 diabetes mellitus (T2DM), which predispose to cardiovascular diseases. Peroxisome proliferator-activated receptor-α (PPARα) has been associated with atherosclerosis, but its role in T2DM is less clear. Previously, we studied PPARα expression levels in diabetics with and without dyslipidemia (DD). In this study we described the association with fasting blood glucose, HbA1c levels and lipid levels of the study population. Patient demography and biochemical data were collected from hospitals in Islamabad, Pakistan, and RT-PCR data of PPARα expression were retrieved from our previous study from the same cohort. We performed t-tests and regression analysis to evaluate the relationships between PPARα expression and demographic and clinical variables. As expected, body mass index and HbA1c were elevated in T2DM and DD patients compared to controls. Blood lipids (total cholesterol, triglycerides, LDL and HDL) were significantly higher in the DD group compared to the other two groups. In the T2DM and DD groups, the PPARα expression was not associated with any of the physical and biochemical parameters measured in this study. Expression of the PPARα gene was independent of blood lipids and glycemic control in this study. Further research is necessary to better understand the biological parameters of PPARα expression. 相似文献
87.
Luis Daniel Sansores-Espaa Samanta Melgar-Rodríguez Rolando Vernal Bertha Arelly Carrillo-vila Víctor Manuel Martínez-Aguilar Jaime Díaz-Zúiga 《International journal of molecular sciences》2022,23(20)
Periodontitis is a chronic non-communicable disease caused by dysbiotic changes that affect the subgingival microbiota. During periodontitis, neutrophils play a central role in the initial recognition of bacteria, and their number increases with the appearance of the first signs of periodontal inflammation. Recent evidence has led to the proposition that neutrophils can also functionally polarize, determining selective activity patterns related to different diseases. Two well-defined neutrophil phenotypes have been described, the pro-inflammatory N1 subset and the suppressor N2 subset. To date, it has not been established whether these different neutrophil subtypes play a role in the pathogenesis of periodontitis. Thus, this scoping review aimed to determine whether there was evidence to suggest that the neutrophils present in periodontal tissues can be associated with certain phenotypes. The research question, population, concept, and context sought to identify original articles, in humans, that detected the presence of neutrophils in the periodontal tissues of people affected by periodontitis. Based on the search strategy, we found 3658 studies. After removing the papers with abstracts not related to the outcome measures and eligibility criteria, 16 articles were included for qualitative analysis. Several studies identified the presence of different neutrophil subsets, specifically, the naive, pro- and para-inflammatory, hyper-reactive and hyper-active, and high- and low-responder phenotypes. The existing evidence demonstrates the presence of pro-inflammatory, hyper-reactive and high-responder neutrophils in periodontal tissues affected with periodontitis. There is no evidence demonstrating the presence of the N1 or N2 phenotypes in periodontal tissues during periodontitis. However, the existence of pro-inflammatory phenotypes, which increase NETosis and degranulation, and increase the production of pro-inflammatory cytokines, could be suggestive of the N1 phenotypes. 相似文献
88.
Telecommunication Systems - Multi-hop communication in a wireless sensor network leads to unbalanced energy consumption, creating “hot spots” around the sensor nodes. Selection of paths... 相似文献
89.
90.
Pradhan Smitirupa Samanta Bhabasankar Samantaray Arun Kumar 《Journal of Mechanical Science and Technology》2020,34(4):1415-1428
Journal of Mechanical Science and Technology - An active steering bogie is designed to for yaw control of the wheel-sets to align the wheels with the track direction during curve negotiation.... 相似文献