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991.
尝试利用Cadidashehatae ATCC 34887、Saccharomyces cerevisiae 2.20251和Saccharomyces cerevisiae 3株酵母功菌发酵棕榈壳的高温液态水水解液和纤维素酶水解液。酶解液与高温液态水水解液相比,发酵较容易,乙醇产率最高达到理论产率的70%,而水解液发酵仍有许多工艺问题值得研究探讨。  相似文献   
992.
993.
催化油浆是催化裂化装置生产汽油、柴油等高附加值产品时产生的副产品,部分供应系统内企业用作焦化原料,其余产出油浆作为燃料油低价销售,效益价值体现不明显.经核算,通过将低附加值的催化油浆作为低硫船用燃料油调和组分,经济价值更高.为进一步降低低硫船用燃料油的生产成本,减轻生产负荷,提高催化产物利用率,将脱固后的油浆加入到调和...  相似文献   
994.
995.
Regulated/activated protein kinase (PRAK) plays a crucial role in modulating biological function. However, the role of PRAK in mediating cardiac dysfunction and metabolic disorders remains unclear. We examined the effects of deletion of PRAK on modulating cardiac function and insulin resistance in mice exposed to a high-fat diet (HFD). Wild-type and PRAK−/− mice at 8 weeks old were exposed to either chow food or HFD for a consecutive 16 weeks. Glucose tolerance tests and insulin tolerance tests were employed to assess insulin resistance. Echocardiography was employed to assess myocardial function. Western blot was used to determine the molecular signaling involved in phosphorylation of IRS-1, AMPKα, ERK-44/42, and irisin. Real time-PCR was used to assess the hypertrophic genes of the myocardium. Histological analysis was employed to assess the hypertrophic response, interstitial myocardial fibrosis, and apoptosis in the heart. Western blot was employed to determine cellular signaling pathway. HFD-induced metabolic stress is indicated by glucose intolerance and insulin intolerance. PRAK knockout aggravated insulin resistance, as indicated by glucose intolerance and insulin intolerance testing as compared with wild-type littermates. As compared with wild-type mice, hyperglycemia and hypercholesterolemia were manifested in PRAK-knockout mice following high-fat diet intervention. High-fat diet intervention displayed a decline in fractional shortening and ejection fraction. However, deletion of PRAK exacerbated the decline in cardiac function as compared with wild-type mice following HFD treatment. In addition, PRAK knockout mice enhanced the expression of myocardial hypertrophic genes including ANP, BNP, and βMHC in HFD treatment, which was also associated with an increase in cardiomyocyte size and interstitial fibrosis. Western blot indicated that deletion of PRAK induces decreases in phosphorylation of IRS-1, AMPKα, and ERK44/42 as compared with wild-type controls. Our finding indicates that deletion of PRAK promoted myocardial dysfunction, cardiac remodeling, and metabolic disorders in response to HFD.  相似文献   
996.
从市场总量、产品分类、生产设备以及行业现状等方面,概括分析了北美地区特种纸行业的整体状况。北美地区58家特种纸公司每年产量总计约为300万t,其中5大特种纸公司各自所占市场份额均超过7%,排名前12位的公司总计占市场份额总量的69%。北美地区特种纸机平均产能居全球第一,但平均技术年龄也最高。造成这一局面的原因在于北美地区特种纸行业发展成熟、市场饱和,近年来对本行业的新投资远落后于全球其他地区。随着各种新技术、新材料的诞生以及对环保、可再生能源等领域的重视,北美特种纸行业将迎来新的发展机遇。  相似文献   
997.
To improve the microstructure and properties of ZrB2-SiC (ZrB2-30?vol%SiC, Z7S3) coatings, a facile synthesis route involving induction plasma spheroidization (IPS) has been proposed, and the morphologies, particle size distributions, and phase compositions of the feedstock powders were analysed by scanning electron microscopy and focused ion beam techniques. The obtained results showed that the surfaces of the produced powders contained eutectic-like and granular zones. Owing to the existence of a temperature gradient, the internal microstructure of the IPS-treated powder exhibited a three-layered structure consisting of a ′surface shell′, a ′transition layer′, and a ′porous core′. Additionally, the properties of the IPS-treated samples were compared with those of the spray-dried (SD) powders. The former exhibited good plastic deformation properties, and their single splats contained flattened structures, while the single splats of the SD powder melted only partially retaining some of their original characteristics.  相似文献   
998.
Multicolor upconversion luminescence materials show significantly applications in materials science. In this paper, the novel Yb3+-sensitized Na3La(VO4)2 upconversion luminescence crystals are synthesized by the solid-state reaction method. Three primary colors upconversion luminescence are successfully achieved in Na3La(VO4)2:Yb3+,Tm3+, Na3La(VO4)2:Yb3+,Er3+, and Na3La(VO4)2:Yb3+,Ho3+ crystals excited by the single 980 nm LD. Multicolor upconversion luminescence can be obtained by simply adjusting the combination ratios of these three samples. Luminescence mechanisms of the Yb3+-sensitized system are discussed in detail. In the Na3La(VO4)2 host material, the Yb3+/Ho3+ codoped system exhibits unusual red upconversion luminescence based on the short decay time of Ho3+ ion 5I6 level, which provides the possibility of three primary color luminescence under 980 nm excitation.  相似文献   
999.
毕秀梅 《给水排水》2021,47(12):92-96,101
以扬州瘦西湖隧道工程为例,介绍了单管双层水底隧道消防及排水系统设计.通过隧道内管道布置位置、最低点废水泵房设备及其压力排水管安装的创新设计,解决了单管双层隧道无专用管廊情况下给排水管道布置问题、隧道狭小空间内的潜污泵及管道安装问题.扬州瘦西湖隧道已开通运行数年,实践证明设计的消防系统合理、排水系统防汛效果良好,创新的设计技术可确保车辆运行安全,方便管理、维修.  相似文献   
1000.
In-situ SiC nanowire (SiCnw)/pyrolytic carbon (PyC) core-shell structures were introduced to mainly improve the thermal shock performance of chemical vapor deposition (CVD)-SiC coating on carbon/carbon (C/C) composites. The microstructure, phase composition, and mechanical properties of the CVD-SiC coating toughened by SiCnw/PyC core-shell structures were studied as well. The results show that the introduction of SiCnw/PyC core-shell structures can effectively alleviate the mismatch of coefficient of thermal expansion (CTE) between SiC coating and C/C substrate, thus enhancing the thermal shock resistance of the coating. Furthermore, the increased numbers of interfaces in the SiC coating owing to the addition of core-shell structures are beneficial to the mechanical properties of the coating after thermal shock test.  相似文献   
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