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91.
Lida T Nakamori R Yabuta R Yada S Takagi Y Mano N Ikegawa S Goto J Nambara T 《Lipids》2002,37(1):101-110
A facile and efficient synthesis of the carboxyl-linked glucosides of bile acids is described. Direct esterification of unprotected
bile acids with 2,3,4,6-tetra-O-benzyl-d-glucopyranose in pyridine in the presence of 2-chloro-1,3,5-trinitrobenzene as a coupling agent afforded a mixture of the
α- and β-anomers (ca. 1∶3) of the 1-O-acyl-d-glucoside benzyl ethers of bile acids, which was separated effectively on a C18 reversedphase chromatography column (isolated yields of α- and β-anomers are 4–9% and 12–19%, respectively). Subsequent hydrogenolysis
of the α- and β-acyl glucoside benzyl ethers on a 10% Pd−C catalyst in acetic acid/methanol/EtOAc (1∶2∶2, by vol) at 35°C
under atmospheric pressure gave the corresponding free esters in good yields (79–89%). Chemical specificities such as facile
hydrolysis and transesterification of the acyl glucosides in various solvents were also discussed. 相似文献
92.
0 引言近年来,在日本营造燃用低质固体燃料的锅炉日益增多,其中主要集中在循环流化床(CFB)锅炉上,这是因为它具有:1)广泛的燃料适应性;2)低的 NO_x 和 SO_2 污染排放。1986年三井公司建造了日本第一台商用 MSFB 锅炉,它被用作 Kuraray 化纤公司的自备动力装置。在此锅炉的设计与运行之前,作者利用试验装置研究了 MSFB 密相床的特性,以保证其性能和运行稳定性。此外,作者还研究了 MSFB 中所采用的固体循环系统在增加燃烧稳定 相似文献
93.
We have found that not only block copolymers but also ionomers can self-assemble in a selective solvent to form surfactant-free nanoparticles. The self-assembly can be induced by chemical reaction, polymer-polymer complexation, and microphase inversion in addition to the temperature. A recently developed microwave method for the preparation of uniform surfactant-free polymeric nanoparticles is also reviewed. Our results have revealed that for a given dispersion, the particle surface area occupied per stabilizer (surfactant, polymer chains, and ionic groups) is close to a constant. 相似文献
94.
Interaction between dietary protein and fat in triglyceride metabolism in the rat: Effects of soy protein and menhaden oil 总被引:4,自引:0,他引:4
The objective of the present study was to determine the mechanisms by which dietary proteins interact with dietary lipids
in the regulation of triglyceridemia in rats. Male Sprague-Dawley rats (n=56) were subjected to 28-d experimental diets containing different combinations of proteins (20% w/w) and lipid sources (14%
w/w): (i) casein-menhaden oil, (ii) casein-beef tallow, (iii) soy protein-menhaden oil, and (iv) soy protein-beef tallow.
Significant protein-lipid interactions were observed on triglyceridemia and hepatic cholesterol in fasted rats. The combination
of casein and beef tallow was associated with high plasma TG and hepatic cholesterol concentrations, which were reduced by
substitution either of soy for casein or of menhaden oil for beef tallow. Therefore, triglyceridemia and liver cholesterol
remained low with soy protein feeding, independently of the lipid source, as well as with menhaden oil feeding, regardless
of the protein source. The menhaden oil diets reduced plasma cholesterol, hepatic TG, and TG secretion compared with beef
tallow diets independently of the dietary protein source. Modifying the source of dietary proteins and lipids had no effect
on post-heparin plasma lipoprotein lipase activity. These results demonstrate that soy protein can lower rat triglyceridemia
relative to casein when associated with beef tallow consumption, whereas menhaden oil can attenuate hypertriglyceridemia when
rats are fed casein. The data further suggest that part of the hypotriglyceridemic effect of soy protein in the rat may be
mediated by reduced hepatic lipid synthesis, as is the case for menhaden oil. 相似文献
95.
A multi-bit antifuse-type one-time programmable (OTP) memory is designed, which has a smaller area and a shorter programming
time compared with the conventional single-bit antifuse-type OTP memory. While the conventional antifuse-type OTP memory can
store a bit per cell, a proposed OTP memory can store two consecutive bits per cell through a data compression technique.
The 1 kbit OTP memory designed with Magnachip 0.18 μm CMOS (complementary metal-oxide semiconductor) process is 34% smaller
than the conventional single-bit antifuse-type OTP memory since the sizes of cell array and row decoder are reduced. And the
programming time of the proposed OTP memory is nearly 50% smaller than that of the conventional counterpart since two consecutive
bytes can be compressed and programmed into eight OTP cells at once. The layout area is 214 μm × 327 μm, and the read current
is simulated to be 30.4 μA.
Foundation item: Project supported by the 2nd Stage of Brain Korea; Project supported by the Korea Research Foundation 相似文献
96.
Associations between apolipoprotein E genotype and circulating F<Subscript>2</Subscript>-isoprostane levels in humans 总被引:1,自引:0,他引:1
Dietrich M Hu Y Block G Olano E Packer L Morrow JD Hudes M Abdukeyum G Rimbach G Minihane AM 《Lipids》2005,40(4):329-334
Apolipoprotein E (apoE), an important determinant of plasma lipoprotein metabolism, has three common alleles (ε2, ε3, and
ε4). Population studies have shown that the risk of diseases characterized by oxidative damage, such as coronary heart disease
and Alzheimer’s disease, is significantly higher in ɛ4 carriers. We evaluated the association between apoE genotypes and plasma
F2-isoprostane levels, an index of lipid peroxidation, in humans. Two hundred seventy-four healthy subjects (104 males, 170
females; 46.9±13.0 yr; 200 whites, 74 blacks; 81 nonsmokers, 64 passive smokers, and 129 active smokers) recruited for a randomized
clinical antioxidant intervention trial were included in this analysis. ApoE genotype was determined by PCR and restriction
enzyme digestion. Free plasma F2-isoprostane was measured by GC-MS. Genotype groups were compared using multiple regression analysis with adjustment for sex,
age, race, smoking status, body mass index, plasma ascorbic acid, and β-carotene. Subjects with ε3/ε4 and ε4/ε4 genotype (ε4-carriers)
and with ε2/ε3 and ε3/ε3 (non-ε4-carriers) were pooled for analysis. In subjects with high cholesterol levels (total cholesterol
above 200 mg/dl), plasma F2-isoprostane levels were 29% higher in ε4 carriers than in non-ε4-carriers (P=0.0056). High-cholesterol subjects that are ε4 carriers have significantly higher levels of lipid peroxidation as assessed
by circulating F2-isoprostane levels. 相似文献
97.
Mg-9Al-xRE magnesium alloys were studied, where, x is 0, 0.4. 0.8. 1.2 and 1.6% (in weight percent, wt%), respectively. Influence of rare earths (RE) on microstructure and strength in both T4 (solute heat treatment) and T6 (solute heat treatment and artificial ageing treatment) were investigated. Strength of specimen was tested at ambient temperature. The micro structure was analyzed by optical microscopy, scanning electron microscopy (SEM) and X-ray diffraction analysis. RE additions improved T4 tensile strength of the treated alloys. Small addition (0.4wt%) of RE greatly improved the strength of ageing treated (T6) Mg-9Al alloy, but further additions caused decreasing. 相似文献
98.
Y.Huang D.M.Xinq 《金属学报(英文版)》2004,17(1):71-76
The influence of alloy composition (Ti,Mn,TiN) on hydrogen diffusion in Fe was studied in detail using SCM-DV-Xα method.The voltage barriers were obtained via calculation on Fe clusters containing the alloy elements such as Ti,Mn as well as the chemical compound TiN respectively.The results showed that Ti element produced deep trap in Fe,decreasing the diffusion coefficient of hydrogen elements,Mn element did not produce deep trap in Fe,decreasing the diffusion coefficient slightly and TiN in Fe produced very deep “trap” decreasing the diffusion coefficient obviously.The calculation results were in agreement with experiment results. 相似文献
99.
Y.P. Lu G. C. Yang C.L. Yang H.P. Wang Y.H. Zhou 《金属学报(英文版)》2006,19(1):43-50
A large undercooling level up to 550K (0.386Te) was achieved in eutectic Ni78.6Si21.4melt by the combination of molten-glass and cyclic superheating. A microcrystaUine structure is obtained at large undercooling. Surprisingly, the morphology of ct(Ni) phase transits from the non-faceted phaseto faceted phase at large undercooling of 390K. Based on the classical nucleation theory and transient nucleation theory, the process of microstructure evolution and competitive nucleation was analyzed, and the refinement of crystal structure is determined by the high nucleation rate under large undercooling. 相似文献
100.
F.P. Wang. P. Wu L.Q. Pan Y. Tian H. Qiu Department of Physics School of Applied Sciences University of Science Technology Beijing Beijing China Beijing Keda-Tianyu Microelectronic Material Technology Development Co. Ltd. Beijing 《金属学报(英文版)》2002,15(2):215-220
1. IntroductionCu filnls are very pron1isillg for electronic devices because of both high electromigrationresista11ce alld high electrical conductivity['--']. For a sputter-deposited film, base pressure,deposition rate, substrate temperature and energetic… 相似文献