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11.
Chung-Kuan Wu Ji-Fan Lin Tzong-Shyuan Lee Yu Ru Kou Der-Cherng Tarng 《International journal of molecular sciences》2021,22(7)
TRPA1, a nonselective cation channel, is expressed in sensory afferent that innervates peripheral targets. Neuronal TRPA1 can promote tissue repair, remove harmful stimuli and induce protective responses via the release of neuropeptides after the activation of the channel by chemical, exogenous, or endogenous irritants in the injured tissue. However, chronic inflammation after repeated noxious stimuli may result in the development of several diseases. In addition to sensory neurons, TRPA1, activated by inflammatory agents from some non-neuronal cells in the injured area or disease, might promote or protect disease progression. Therefore, TRPA1 works as a molecular sentinel of tissue damage or as an inflammation gatekeeper. Most kidney damage cases are associated with inflammation. In this review, we summarised the role of TRPA1 in neurogenic or non-neurogenic inflammation and in kidney disease, especially the non-neuronal TRPA1. In in vivo animal studies, TRPA1 prevented sepsis-induced or Ang-II-induced and ischemia-reperfusion renal injury by maintaining mitochondrial haemostasis or via the downregulation of macrophage-mediated inflammation, respectively. Renal tubular epithelial TRPA1 acts as an oxidative stress sensor to mediate hypoxia–reoxygenation injury in vitro and ischaemia–reperfusion-induced kidney injury in vivo through MAPKs/NF-kB signalling. Acute kidney injury (AKI) patients with high renal tubular TRPA1 expression had low complete renal function recovery. In renal disease, TPRA1 plays different roles in different cell types accordingly. These findings depict the important role of TRPA1 and warrant further investigation. 相似文献
12.
通过对用于麻石烟气脱硫装置的2^#和3^#耐酸胶泥的单因素对比试验的研究,得出2^#胶泥耐酸度较好,因而防腐蚀性能也较好。这不仅回收了固废,而且还具有可观的环境效益。 相似文献
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Guang Su Huang Xiang Ru He Jing Rong Wu Qi Ying Pan Jing Zhen Zhuo Hong 《应用聚合物科学杂志》2006,102(4):3127-3133
In this study, a kind of novel damping materials was prepared based on the blend of chlorinated butyl rubber (CIIR) and polyacrylate (PAc) synthesized by different molar ratio of butyl methacrylate and ethyl acrylate. Research results from experiments and analyses by employing DMA, TEM, and FTIR show that whether at a cocured system or noncocured system, it can be achieved to shift a loss peak of CIIR towards a higher temperature region and to keep the damping value from markedlly decreasing, which broadens the effective damping function area of CIIR to the vicinity of ambient temperature. In the former system, the thermodynamical miscibility of CIIR and PAc, to some extent, is predominated by the molecular design of PAc, while in the latter system, covulcanized networks play a more significant role in improving compatibility and abating the peak split, though the suppression effect of thermal stress on the transition of CIIR Tll transition still can not be neglected. Furthermore, transition state derived from the cocuring CIIR and PAc cannot make the phase separation completely take place, and consequently results in the deformation of phase morphology of the cocured CIIR/PAc blend. It is the influence of thermodynamics miscibility and forced compatibility in different size that makes the suppression effect of foreign PAc on CIIR Tll transition be controllable. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 102: 3127–3133, 2006 相似文献
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高效节能换热器在氮肥工业中的应用 总被引:1,自引:0,他引:1
描述了新型折流杆换热器的强化传热和降低壳层压力降的原理 ,它与传统折流板换热器相比 ,传热效率高 ,材料及能耗小。介绍了这种新型换热器在合成氨变换工段和尿素装置中的应用情况及所起的节能降耗作用 ,指出该高效节能换热器在设计和生产中的关键技术。 相似文献
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The influence of styrene-butadiene rubber (SBR) latex on cement hydrates Ca(OH)2, ettringite, C4AH13 and C-S-H gel and the degree of cement hydration is studied by means of several measure methods. The results of DSC and XRD show that the Ca(OH)2 content in wet-cured SBR-modified cement pastes increases with polymer-cement ratio (P/C) and reaches a maximum when P/C is 5%, 10% and 10% for the pastes hydrated for 3 d, 7 d and 28 d, respectively. With wet cure, appropriate addition of SBR promotes the hydration of cement, while the effect of SBR on the content of Ca(OH)2 and the degree of cement hydration is not remarkable in mixed-cured SBR-modified cement pastes. XRD results illustrate that SBR accelerates the reaction of calcium aluminate with gypsum, and thus enhances the formation and stability of the ettringite and inhibits the formation of C4AH13. The structure of aluminum-oxide and silicon-oxide polyhedron is characterized by 27Al and 29Si solid state NMR spectrum method, which shows that tetrahedron and octahedron are the main forms of aluminum-oxide polyhedrons in SBR-modified cement pastes. There are only [SiO4]4− tetrahedron monomer and dimer in the modified pastes hydrated for 3 d, but there appears three-tetrahedron polymer in the modified pastes hydrated for 28 d. The effect of low SBR dosage on the structure of aluminum-oxide and silicon-oxide polyhedron is slight. However, the combination of Al3+ with [SiO4]4− is restrained when P/C is above 15%, and the structure of Al3+ is changed obviously. Meantime, the polymerization of the [SiO4]4− tetrahedron in C-S-H gel is controlled. 相似文献
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The structure of benzoxazines is similar to that of phenolic resin through thermal self‐curing of the heterocyclic ring opening reaction that neither requires catalyst nor releases any condensation byproduct. These polybenzoxazine resins have several outstanding properties such as high thermal stability and high glass transition temperature. To better understand the curing kinetics of this copolybenzoxazine thermosetting resin, dynamic and isothermal differential scanning calorimetry measurements were performed. Three models, the Kissinger method, the Flynn–Wall–Osawa method, and the Kamal method, were used to describe the curing process. Dynamic kinetic activation energies based on Kissinger and Flynn–Wall–Osawa methods are 72.11 and 84.06 KJ/mol, respectively. The Kamal method based on an autocatalytic model results in a total order of reaction between 2.66 and 3.03, depending on curing temperature. Its activation energy and Arrhenius preexponential are 50.3 KJ/mol and 7959, respectively. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 95: 730–737, 2005 相似文献