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排序方式: 共有2258条查询结果,搜索用时 23 毫秒
71.
Ewelina Ziemliska Justyna Sobociska Anna
witkowska Aneta Hromada-Judycka Gabriela Traczyk Agata Malinowska Bianka
widerska Anna Mietelska-Porowska Anna Ciesielska Katarzyna Kwiatkowska 《International journal of molecular sciences》2021,22(23)
Palmitic acid (C16:0) is the most abundant saturated fatty acid in animals serving as a substrate in synthesis and β-oxidation of other lipids, and in the modification of proteins called palmitoylation. The influence of dietary palmitic acid on protein S-palmitoylation remains largely unknown. In this study we performed high-throughput proteomic analyses of a membrane-enriched fraction of murine liver to examine the influence of a palm oil-rich diet (HPD) on S-palmitoylation of proteins. HPD feeding for 4 weeks led to an accumulation of C16:0 and C18:1 fatty acids in livers which disappeared after 12-week feeding, in contrast to an accumulation of C16:0 in peritoneal macrophages. Parallel proteomic studies revealed that HPD feeding induced a sequence of changes of the level and/or S-palmitoylation of diverse liver proteins involved in fatty acid, cholesterol and amino acid metabolism, hemostasis, and neutrophil degranulation. The HPD diet did not lead to liver damage, however, it caused progressing obesity, hypercholesterolemia and hyperglycemia. We conclude that the relatively mild negative impact of such diet on liver functioning can be attributed to a lower bioavailability of palm oil-derived C16:0 vs. that of C18:1 and the efficiency of mechanisms preventing liver injury, possibly including dynamic protein S-palmitoylation. 相似文献
72.
Qiang Wang Ji Hyang Sohn So Ye Park Jin Seong Choi Joo Young Lee Jong Shik Chung 《Journal of Industrial and Engineering Chemistry》2010,16(1):68-73
Pure phase K4Zr5O12 is synthesized via solid state method in the present work. Various K/Zr ratios and temperatures are applied, and the synthesis process is investigated in detail by means of X-ray diffraction, Fourier transform infrared spectroscopy, scanning electron microscopy, and X-ray photoelectron spectroscopy. Its catalytic activity for soot oxidation is studied by temperature programmed oxidation with different types of soot/catalyst contacts. It is revealed that K4Zr5O12 is very active in the presence of 2–10% O2 for both tight and loose contacts (Tp(tight) = 335 °C, Tp(ethanol) = 355 °C and Tp(shaking) = 370 °C). Thermal stability study shows that K4Zr5O12 is highly stable up to at least 900 °C. 相似文献
73.
Development of dieldrin,endosulfan, and hexachlorobenzene‐imprinted polymers for dye‐displacement array sensing 下载免费PDF全文
Ofelia V. Silverio Regina C. So Katrina Jean S. Elnar Christian A. Malapit Ma. Cristine M. Nepomuceno 《应用聚合物科学杂志》2017,134(2)
Due to the toxicity associated with the exposure to organochlorine pesticides, new materials capable of selectively capturing and detecting these compounds are highly desirable. In this study, imprinted polymers were prepared using three organochlorine pesticides—dieldrin (DE), endosulfan (EN), or hexachlorobenzene (HCB) as templates. The MIPs were polymerized via precipitation polymerization. The yields were over 90% with particle sizes ranging from 62 to 214 nm. Binding studies combined with GC‐ECD analysis showed that each template is more selective to its corresponding MIP compared with the other two structurally homologous templates. These results were consistent with those obtained using UV–vis where more bromocresol green (BCG) dye was released when higher template concentrations were introduced to the corresponding BCG‐impregnated MIPs. Since unique selectivity response pattern for each of the MIPs was obtained, this demonstrated that the MIPs were selective and can be potentially used in dye‐displacement array sensing. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017 , 134, 44401. 相似文献
74.
Magdalena Hofman-Bieniek Katarzyna Jasiewicz Robert Pietrzak 《Korean Journal of Chemical Engineering》2014,31(2):304-309
Preparation of polymeric membranes based on polyethersulfone (PES) modified by adding different amounts of a pore-forming agent (PVP) is presented, and potential application of the membranes obtained for removal of phenol from the liquid phase is examined. The addition of various amounts of PVP has been shown to bring about changes in the content of the surface oxygen groups, but has no significant effect on the chemical character of the groups and acidic groups dominate. Filtration by phenol solution leads to significant changes in the total content of surface oxides; however, the acidic groups remain dominant. Membranes characterized by higher porosity exhibited more stable and higher rejection ratio for phenol removal. Although all the membranes were characterized by similar rejection ratios for phenol removal, the cake resistance (Rc) and pore resistance (Rp) values were found to depend significantly on the structure and porosity of the membrane applied for filtration. 相似文献
75.
76.
Katarzyna Szymczyk Magdalena Szaniawska Konrad Terpiłowski 《Journal of surfactants and detergents》2019,22(5):1163-1174
Measurements of density, speed of sound, and surface tension as well as viscosity of aqueous Kolliphor® ELP (ELP) and Kolliphor® RH 40 (RH40) solutions as well as binary mixtures at different surfactant mole fractions were made at 293 K to investigate their aggregation behavior. The free volume, internal pressure, and molar cohesive energy were calculated and compared to the specific acoustic impedance and intermolecular free length to obtain qualitative information about the character of interactions between the surfactant molecules in the mixture through the water phase. 相似文献
77.
Won So Young-Hun Kim Chang Jun Lee Dongil Shin En Sup Yoon 《Korean Journal of Chemical Engineering》2011,28(3):656-666
Accidents involving domino effects are more serious than other type of accidents. Although there have been studies on such accidents, it is still difficult to examine the actual factors and causes since the domino effect is influenced nonlinearly by factors involving flame, overpressure, and flying objects. We considered the case of adding new facilities to an existing system in a given site. The layout of new facilities suggests positions that minimize the domino effects, based on nonlinear optimization taking domino factors into account. We quantitatively calculated the domino risk of each facility through the concept of combined domino factors (flame, overpressure, and missile). Also, we identified variations of domino damage extent of the target system through comparison of the impacts of domino effect when additional facilities were installed. Simulated annealing was adopted for searching optimal positions. As a case study, we applied the proposed method to the case of adding DME storage tanks in the existing LPG charging facilities. The presented framework of the quantitative assessment of domino risk and safety standard for the layout of additional facilities would be useful for proper layout design for improved accident prevention. 相似文献
78.
Kazimierz MroczekSylwester Kalisz Marek PronobisJózef So?tys 《Fuel Processing Technology》2011,92(5):845-855
The paper presents results of investigations on using halloysite as an additive in biomass-fired boilers. It has been shown that in the case of a few different agricultural biomasses the halloysite addition increased the ash sintering temperature to the values noted for coals. This is an effect of bonding sodium and potassium in the form of chlorides and other compounds. In practical terms the halloysite additive may reduce slagging and fouling of boiler heating surfaces as well as deteriorate the agglomeration processes in fluidized beds. Moreover, addition of halloysite reduces the amount of KCl and NaCl present in ash (and therefore in ash deposits) thus decreasing the rate of high temperature corrosion. 相似文献
79.
80.
Branched polyethylenimine (b-PEI), an amine-rich polymer, can obtain thermosensitivity by a simple acylation reaction. The resulting N-acylated b-PEI derivatives showed a similar lower critical solution temperature (LCST) transition as their linear correspondent, poly(N-alkyloxazoline). Three acyl groups (propionyl, and isobutyryl, and n-butyryl) were introduced and resulted in LCSTs ranging from 10 °C to 90 °C depending on the structure and environment. The hydrophobicity of N-acylated b-PEI can be controlled by varying the acyl group and degree of acylation. Because the LCST transition is determined by the delicate balance between the hydrophobicity and hydrophilicity of the polymers, an increase of the hydrophobicity in N-acylated b-PEI lowers the transition temperature. Also, N-acylated b-PEI contains tertiary amines as well as unacylated primary or secondary amines which can be protonated during acidification from a pH of 7.4 to a pH of 5.5. The LCST transition was observed at elevated temperatures due to the increase of hydrophilicity by the protonation in the acidic environment. The LCST was also influenced by the salt concentration. A decrease of the LCST was observed as the NaCl concentration increased, probably due to the dominance of the salting-out effect. The very simple introduction of thermosensitivity into pre-existing polymers can be easily applied for the development of various dual or multiple signal-sensitive polymer systems. 相似文献