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991.
In order to mitigate the corrosion of steel rebar in concrete, a new environmentally friendly corrosion inhibitor formula (WKI) was designed and the corrosion inhibitive effects of WKI on steel rebar were studied by gravimetric method, electrochemical impendence spectroscopy (EIS), potentiodynamic polarization and Mott–Schottky scanning in simulated concrete pore solution. Furthermore, surface analysis and quantum chemical calculations were conducted in order to illustrate the corrosion inhibitive mechanism. The results indicate that WKI exhibits excellent corrosion inhibitive activities on steel rebar in simulated concrete pore solution. By the presence of WKI, local corrosion was significantly suppressed and no pitting could be detected during the whole experimental period. The total corrosion resistance was increased from 5469 Ω cm2 to 64 440 Ω cm2 and the corrosion current density was reduced from 3.23 μA cm−2 to 0.21 μA cm−2 for the sample immersed in the corrosion medium for 7 d with WKI. The corrosion potential of the steel rebar electrode moved to a higher level and the charge transfer resistance increased, indicating that the anti-corrosion properties of the steel rebar were enhanced. The corrosion inhibitive mechanism of WKI can be attributed to the fact that it can promote the formation of a passive film and reduce its defect concentration via its adsorption and interaction with the metal surface, consequently inhibiting the corrosion of steel rebar caused by chloride ions.A new corrosion inhibitor formula was designed and the inhibitive mechanism was analyzed based on HSAB theory and the PDM model. 相似文献
992.
Dye-sensitized solar cells (DSSCs), different in principle from the conventional solar cells based on p–n junctions, are competitively cost-effective. For development of this kind of emerging solar cell, it is very significant to reduce their cost and improve their energy conversion efficiency to the maximum extent. In this article, ternary composites (Ni–PANI–G composites) consisting of nickel nanoparticles, polyaniline (PANI), and graphene (G) were prepared for the first time and used as counter electrodes to replace the noble metal Pt in DSSCs. In the case of PANI, the introduction of Ni nanoparticles can improve the electrocatalytic ability for the reduction of triiodide ions in the counter electrode, while in the meantime, the addition of graphene in the Ni–PANI–G composites can increase the electrical conductivity of the counter electrode. The optimized DSSCs fabricated by using the Ni–PANI–G composites as the counter electrode exhibit an overall power conversion efficiency of 5.80% compared to 5.30% for reference platinum (Pt) counter-electrodes. Electrochemical impedance spectra (EIS) show that the charge-transfer resistance at the interface between electrolyte and counter-electrode in the case of the ternary composite is obviously decreased. These results are significant to develop low-cost counter electrode materials for DSSCs.In this article, ternary composites (Ni–PANI–G composites) consisting of nickel nanoparticles, polyaniline (PANI), and graphene (G) were prepared for the first time and used as counter electrodes to replace the noble metal Pt in DSSCs. 相似文献
993.
Reconstruction of structure and function in tissue engineering of solid organs: Toward simulation of natural development based on decellularization 下载免费PDF全文
Cheng‐Hu Hu Xin‐Yu Qiu Pan Zhao Yan Jin 《Journal of tissue engineering and regenerative medicine》2018,12(6):1432-1447
Failure of solid organs, such as the heart, liver, and kidney, remains a major cause of the world's mortality due to critical shortage of donor organs. Tissue engineering, which uses elements including cells, scaffolds, and growth factors to fabricate functional organs in vitro, is a promising strategy to mitigate the scarcity of transplantable organs. Within recent years, different construction strategies that guide the combination of tissue engineering elements have been applied in solid organ tissue engineering and have achieved much progress. Most attractively, construction strategy based on whole‐organ decellularization has become a popular and promising approach, because the overall structure of extracellular matrix can be well preserved. However, despite the preservation of whole structure, the current constructs derived from decellularization‐based strategy still perform partial functions of solid organs, due to several challenges, including preservation of functional extracellular matrix structure, implementation of functional recellularization, formation of functional vascular network, and realization of long‐term functional integration. This review overviews the status quo of solid organ tissue engineering, including both advances and challenges. We have also put forward a few techniques with potential to solve the challenges, mainly focusing on decellularization‐based construction strategy. We propose that the primary concept for constructing tissue‐engineered solid organs is fabricating functional organs based on intact structure via simulating the natural development and regeneration processes. 相似文献
994.
Wenming Ren Huaijiang Xiang Chengyuan Peng Zulipali Musha Jingjing Chen Xin Li Ruimin Huang Youhong Hu 《RSC advances》2018,8(10):5542
A copper-catalyzed direct C–H arylation or vinylation of BODIPYs at the β-position by iodonium salts has been developed, which provides facile access to a variety of mono-substituted BODIPY dyes. Interestingly, β-styryl BODIPY compound 9b exhibits apparent cytotoxicity after laser irradiation, which has great potential for photodynamic therapy.A copper-catalyzed direct C–H arylation or vinylation of BODIPYs at the β-position by iodonium salts has been developed and β-styryl BODIPY 9b has great potential for photodynamic therapy. 相似文献
995.
凝血酶敏感蛋白1(thrombospondin-1,TSP-1)是一种分泌性细胞外基质糖蛋白,具有多个功能区域,可以结合不同的蛋白或受体,如转化生长因子β(transforming growth factor-β,TGF-β)、CD36、CD47及整合素等,介导血管新生、细胞黏附、血小板聚集及免疫反应等。机体多种细胞可以合成TSP-1,如血小板、血管内皮细胞、平滑肌细胞、脂肪细胞、成纤维细胞、肝星状细胞、角质细胞等。近年来,随着TSP-1在肿瘤、代谢的调控作用的研究深入,其在脂质代谢、胰岛素抵抗、非酒精性脂肪肝等糖脂代谢中发挥的作用正逐渐被人们认识。 相似文献
996.
Wenhao Zhai Chaoyang Ge Xin Fang Kun Zhang Cheng Tian Kai Yuan Shuren Sun Yanping Li Weixi Chen Guangzhao Ran 《RSC advances》2018,8(26):14527
We adopt an acetone vapour-assisted method to grow high quality single-crystalline microplates of two-dimensional (2D) perovskite, 2-phenylethylammonium lead bromide [(C6H5C2H4NH3)2PbBr4]. The microplates, converted from the spin-coated films, are well-defined rectangles. Temperature dependent photoluminescence (PL) spectroscopy shows that the band gap PL is enhanced markedly with increasing temperature up to 218 K, accompanied by the quenching of the PL related to the trap states, which perhaps results from the exciton–phonon couplings. The optical phonon energy around 50 meV and the exciton binding energy around 120 meV are derived by fitting the band gap PL linewidths and intensities at different temperatures, respectively.We report an acetone vapour-assisted method to grow single-crystalline 2D perovskite microplates and find their temperature-enhanced photoluminescence. 相似文献
997.
Free nitrous acid (FNA) is a promising chemical reagent for excess sludge reduction. The distinctive properties of FNA treatment on waste activated sludge (WAS) disposal have previously been demonstrated, however, the cellular response, permeabilization, and disruption caused by low-concentration FNA and the direct cell solubilization of WAS using concentrated FNA should be better understood. In this study, the parameters that influence the sludge solubilization efficiency were optimized over a wide range of FNA concentrations. The sludge solubilization efficiency was found to be superior when the sludge was exposed to FNA (when the dosage of NaNO2 was 0.12 g g−1 TSS and the pH was 3.0, FNA = 20.94 mg L−1) for 10 h at 25 °C, and the TSS removal and COD dissolution efficiencies were found to be prominent at 38% and 7%, respectively. In the FNA treatment of WAS, some FNA-tolerable cells increased the K+, Ca2+, and H+ effluxes under low concentrations of FNA, and finally achieved ion homeostasis based on the results using a scanning ion-selective electrode measurement technique. This could cause the cells in WAS to maintain cytoactivity and integrity under a low-concentration FNA treatment. Furthermore, flow cytometry was used to assess the permeabilization and disruption of sludge cells toward a concentration gradient of FNA. Flow cytometry results indicated that cells in sludge flocs were disrupted within 30 minutes when the FNA concentration was above 8 mg L−1.The mechanism of sludge solubilization induced by free nitrous acid over a large concentration range was investigated using SIET and FCM. 相似文献
998.
Serogroup B Meningococcal Disease Outbreak and Carriage Evaluation at a College — Rhode Island, 2015
Heidi M. Soeters Lucy A. McNamara Melissa Whaley Xin Wang Nicole Alexander-Scott Koren V. Kanadanian Catherine M. Kelleher Jessica MacNeil Stacey W. Martin Nathan Raines Steven Sears Cynthia Vanner Jeni Vuong Utpala Bandy Kenneth Sicard Manisha Patel 《MMWR. Morbidity and mortality weekly report》2015,64(22):606-607
999.
目的:为提高医疗绩效评价水平、提升医院的内涵质量和医疗服务效率,上海市肺科医院利用CMI工具在学科绩效建设模式方面进行了探索性的研究与实践。方法:以上海市肺科医院2012年7月-2013年6月胸外科住院患者数据为基础,建立基于临床路径与DRGs大数据支持下的以CMI为核心的学科绩效评价模式。结果:2013年7月-2014年6月该院胸外科平均CMI值由上年同期的基准值1.00升高至1.06(增加6%),单病种均次费用下降,所有医疗组的校正平均住院天数均降低。结论:以CMI为核心的学科绩效评价模式,能够在保证医疗内涵质量的前提下,实现提高疑难危重患者收治率、缩短平均住院日和控制费用的目标。 相似文献
1000.
This study investigated the relationship between IL-33/ST2 signal pathway gene polymorphisms and myocardial infarction(MI) in Han Chinese. A case-control association analysis was performed on a total of 490 MI patients(MI group) and 929 normal subjects(NC group). Sequenom Mass Array and Taqman genotyping technique were used to analyze the tag single nucleotide polymorphisms(SNPs) in the genes encoding IL-33, ST2, and IL-1Ra P(rs11792633, rs1041973 and rs4624606). The results showed that the frequencies of rs4624606 genotypes AA, TT, AT were 0.031, 0.647, 0.322 in MI group and 0.026, 0.712, 0.263 in NC group, and the allele frequencies of A and T were 0.192, 0.808 in MI group and 0.157, 0.843 in NC group. There were significant differences in rs4624606 genotypes and allele frequencies between MI group and NC group(P<0.05). For rs11792633, the allele frequencies of C and T were 0.45, 0.55 in MI group and 0.454, 0.546 in NC group with no significant differences found between the two groups. Compared with genotype CC+TC, rs11792633 genotype TT had an increased risk of hypertension(P<0.05). However, there were no significant differences in the frequencies of rs11792633 genotypes between the two groups. No significant differences were noted in the frequencies of rs1041973 genotype and allele between the two groups. Logistic regression analysis showed that rs4624606 genotypes AT and AA+AT were both significantly associated with MI(AT: OR=1.325, P=0.029, 95% CI=1.03–1.705; AA+AT: OR=1.316, P=0.028, 95% CI=1.03–1.681) after factors such as age, gender, smoking, drinking, body mass index(BMI), triglyceride(TG) and cholesterol were adjusted. Those carrying rs4624606 genotype AT or AA+AT had an increased risk of MI. No associations were found between the polymorphisms of the other two loci with MI. It was concluded that, in the IL33/ST2 signal pathway, the A allele of rs4624606 polymorphism of IL-1Ra P gene is a potential independent risk factor for MI, and the genotypes AA+AT and AT are associated with the incidence of MI. 相似文献