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71.
Shiro Saka  Yohei Isayama  Zul Ilham  Xin Jiayu 《Fuel》2010,89(7):1442-1446
The production of glycerol as a by-product is unavoidable in the current conventional biodiesel manufacturing processes. Since biodiesel production is expected to increase in the near future, effective utilization of glycerol will become an issue of interest. In this study, therefore, a process consisting of subcritical acetic acid treatment to convert rapeseed oil to fatty acids and triacetin followed by conversion of the obtained fatty acids to their fatty acid methyl esters in supercritical methanol treatment was investigated. The obtained results clearly revealed that this two-step reaction could proceed effectively at a high reaction rate, and that fatty acid methyl esters and triacetin could be obtained under milder reaction condition than the one-step process utilizing supercritical methyl acetate and supercritical methanol.  相似文献   
72.
该文针对摄入醋酸菌对于酒精性肝损伤的影响进行了评价。将C57BL/6J小鼠(8周龄,雄性,22~27 g)分为对照组(非乙醇给药组)、乙醇组(给予2.5 g/kg乙醇)、乙醇+醋酸菌组(给予2.5 g/kg乙醇+10 mg醋酸菌),分别每天给药3次,连续经口给药14 d,测定了血清谷草转氨酶(AST)、谷丙转氨酶(ALT)及肝脏油脂浓度。结果表明,与对照组相比较,乙醇组小鼠的AST与ALT浓度,肝脏甘油三酯与胆固醇浓度显著增高(P<0.05);乙醇+醋酸菌组的数值则显著低于乙醇组(P<0.05)。以上结果表明,摄入醋酸菌有可能会减轻酒精性肝损伤。  相似文献   
73.
Immune phage antibody libraries are an attractive technology for isolating antigen-specific monoclonal antibodies (mAbs). Here we show that the immunization schedule affects the immune phage antibody library properties. We subcutaneously (s.c.) administered HIV-1 Nef and Vif antigens with different schedules (25 μg × 2 s.c. and 10 μg × 3 s.c.). The variety of isolated mAbs in 25 μg × 2 s.c. groups (Nef: 11 clones, Vif: 9 clones) was superior to that in the 10 μg × 3 s.c. groups (Nef: 2 clones, Vif: 1 clone). This finding suggests that it is important to optimize the immunization schedule for isolating a wide variety of mAbs.  相似文献   
74.
Antimonic acid with the monoclinic structure, M-SbA, which had a high selectivity for the lithium ion among alkali metal ions, was prepared by extracting lithium ions from LiSbO3 through ion exchange with protons and its lithium isotope selectivity has been studied. M-SbA underwent the reversible monoclinic-orthorhombic structural change upon desorption-sorption of lithium ions while it showed the irreversible monoclinic-cubic structural change upon sorption of sodium ions. Isotopically, M-SbA was a 6Li-specific ion exchanger. The 7Li-to-6Li isotopic separation factor was slightly dependent on the kinds of counterion in the solution phase of the batch experiments and the maximum S value obtained at 25°C was 1.025.  相似文献   
75.
Free-radical polymerization of an imidazolium ion-based ionic liquid bearing a methacrylate group, gelling with single-walled carbon nanotubes (SWNTs), allows fabrication of a mechanically reinforced, electroconductive soft material (bucky plastic). A film sample of this material displays an excellent conductivity of 1 S cm(-1) and a 120-fold enhancement of the Young's modulus at a 7 wt % content of SWNTs. The conductivity is temperature-dependent in the range 5-300 K, suggesting that the conductive process involves carrier hopping. Scanning electron and atomic force micrographs of a bucky plastic film display the presence of crosslinked networks consisting of finely dispersed SWNTs. Such nanotube networks, developed in the polymer matrix, likely suppress slipping of entrapped polymer molecules via a strong interfacial interaction and also facilitate intertubular carrier transport. Although a bucky plastic derived from a vinylimidazolium ion-based ionic liquid monomer shows a comparable conductivity to that of the methacrylate version, the film is brittle irrespective of the presence or absence of SWNTs.  相似文献   
76.
Because of their useful chemical and physical properties, nanomaterials are widely used around the world - for example, as additives in food and medicines - and such uses are expected to become more prevalent in the future. Therefore, collecting information about the effects of nanomaterials on metabolic enzymes is important. Here, we examined the effects of amorphous silica particles with various sizes and surface modifications on cytochrome P450 3A4 (CYP3A4) activity by means of two different in vitro assays. Silica nanoparticles with diameters of 30 and 70 nm (nSP30 and nSP70, respectively) tended to inhibit CYP3A4 activity in human liver microsomes (HLMs), but the inhibitory activity of both types of nanoparticles was decreased by carboxyl modification. In contrast, amine-modified nSP70 activated CYP3A4 activity. In HepG2 cells, nSP30 inhibited CYP3A4 activity more strongly than the larger silica particles did. Taken together, these results suggest that the size and surface characteristics of the silica particles determined their effects on CYP3A4 activity and that it may be possible to develop silica particles that do not have undesirable effects on metabolic enzymes by altering their size and surface characteristics.  相似文献   
77.
Using a turbostratic pyrolytic boron nitride as a starting material, we synthesized a variety of ultrahard polycrystalline cubic boron nitride (PcBN) as a function of the heating duration changing from 1 to 60?min under a constant temperature and pressure conditions (1950?°C and 25?GPa) using a multi-anvil apparatus. When the heating duration was less than 13?min, ultrafine nano-polycrystalline cBN (U-NPcBN) with the mean grain size of <50?nm was produced. Among these U-NPcBNs those synthesized with 11–13?min were found to have a uniform texture composed purely of cBN (i.e. with no wurzite BN residue) and a Knoop hardness of >53?GPa, which is 20% higher than that of the hardest conventional binderless PcBN in practical use. Furthermore, the PcBNs synthesized with 18–20?min showed a unique nanocrystalline texture composed of relatively coarse grains dispersed in a fine grained matrix and even higher Knoop hardness (54.5–55.2?GPa).  相似文献   
78.
Near-infrared (NIR)-shielding films based on polysiloxane or polysilsesquioxanes and poly(3,4-ethylenedioxythiophene)-poly(4-styrene sulfonate) (PEDOT-PSS) were synthesized via a sol–gel reaction. Phase-separated mixtures of tetraethyl orthosilicate (TEOS) or methyltriethoxysilane (MTES) with an aqueous dispersion of PEDOT-PSS formed deep-blue homogeneously dispersed sols after stirring. Thin films were prepared by depositing the resulting homogeneously dispersed sols on a glass substrate by spin coating and heating. PEDOT-PSS/TEOS films maintained uniform flat surfaces after 10 coatings. MTES-based films exhibited mottled patterns with nonuniform surfaces. The 10-layer TEOS-based film has high NIR-shielding properties with moderately visible transmittance. NIR absorption by the PEDOT-PSS/TEOS hybrid suppresses air temperature elevation. The five-layer TEOS-based film showed similar NIR-shielding ability and slightly lower visible light transmittance compared with tin-doped indium oxide glass. The 10-layer TEOS-based film exhibited a 15.6% lower temperature rise than the uncoated glass substrate. Specifically, this is an environmentally friendly NIR-shielding material. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2020 , 137, 48367.  相似文献   
79.
This study aimed to evaluate skeletal pain associated with osteoporosis and to examine the inhibitory effects of cytotoxic T lymphocyte-associated antigen-4Ig (CTLA-4Ig) administration in ovariectomized (OVX) mice. Eight-week-old female ddY mice were assigned to three groups: sham-operated mice (SHAM) treated with vehicle, OVX mice treated with vehicle (OVX), and OVX mice treated with CTLA-4Ig (CTLA-4Ig). Vehicle or CTLA-4Ig was injected intraperitoneally, starting immediately after surgery. After 4 weeks of treatment, mechanical sensitivity was examined, and the bilateral hind limbs were removed and evaluated by micro-computed tomography, immunohistochemical analyses, and messenger RNA expression analysis. Ovariectomy induced bone loss and mechanical hyperalgesia in the hindlimbs. CTLA-4Ig treatment prevented bone loss in the hindlimbs compared to vehicle administration in the OVX group. Moreover, mechanical hyperalgesia was significantly decreased in the CTLA-4Ig treatment group in comparison to the OVX group. The expression levels of tumor necrosis factor-α (TNF-α) and sclerostin (SOST), as well as the number of osteoclasts, were increased, and the expression level of Wnt-10b was decreased in the OVX group compared with the SHAM group, whereas these parameters were improved in the CTLA-4Ig group compared with the OVX group. The novelty of this research is that CTLA-4Ig administration prevented bone loss and mechanical hyperalgesia induced by ovariectomy in the hindlimbs.  相似文献   
80.
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