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排序方式: 共有520条查询结果,搜索用时 15 毫秒
101.
Differential scanning calorimetric studies on structured lipids from coconut oil triglycerides containing stearic acid 总被引:1,自引:0,他引:1
Reena Rao Kadimi Udaya Sankar Kari Sambaiah B. R. Lokesh 《European Food Research and Technology》2001,212(3):334-343
Triglycerides from coconut oil contain high levels of lauric acid. They were replaced by incremental amounts of stearic acid by interesterification reactions catalyzed by immobilized lipase (IM 60 from Rhizomucor miehei). The reactions were carried out in organic solvents such as hexane. Maximum incorporation of stearic acid was observed by 4 h at 37vv°C or by 2 h at 60vv°C when triglycerides to fatty acid (stearic acid) ratio was maintained at 1v:Ң. The stearic acid level in coconut oil triglycerides was increased from an initial value of 2% to 60% under these conditions. The stearic acid replaced lauric, myristic, and palmitic acids in unmodified triglycerides. A major portion of stearic acid incorporated was found in positions 1 and 3 of triglycerides. Differential scanning calorimetry indicated that stearic acid enrichment increased the solid fat content and also the higher melting polymorphs in modified lipids. The studies also indicated that low melting polymorphic forms of coconut oil triglycerides are converted to higher melting forms by stearic acid enrichment. The modified lipids thus obtained can find use in various food applications. 相似文献
102.
Esraa Ali Andriy Trailin Filip Ambrozkiewicz Vclav Lika Kari Hemminki 《International journal of molecular sciences》2022,23(23)
Hepatocellular carcinoma (HCC) is a global healthcare challenge, which affects more than 815,000 new cases every year. Activated hepatic stellate cells (aHSCs) remain the principal cells that drive HCC onset and growth. aHSCs suppress the anti-tumor immune response through interaction with different immune cells. They also increase the deposition of the extracellular matrix proteins, challenging the reversion of fibrosis and increasing HCC growth and metastasis. Therapy for HCC was reported to activate HSCs, which could explain the low efficacy of current treatments. Conversely, recent studies aimed at the deactivation of HSCs show that they have been able to inhibit HCC growth. In this review article, we discuss the role of aHSCs in HCC pathophysiology and therapy. Finally, we provide suggestions for the experimental implementation of HSCs in HCC therapies. 相似文献
103.
Palladium-Catalyzed Domino Reaction for the Synthesis of 3-Amino 1,2,4-Benzothiadiazine 1,1-Dioxides
Renè Hommelsheim Robin van Nahl Lena M. Hanek Jas S. Ward Kari Rissanen Carsten Bolm 《Advanced Synthesis \u0026amp; Catalysis》2024,366(4):717-724
A palladium-catalyzed domino reaction of 2-azidosulfonamides and isocyanides enables the synthesis of 3-amino-substituted 1,2,4-benzothiadiazine 1,1-dioxides at room temperature. By applying commercially available Pd(dba)2 in catalyst loadings as low as 1.0 mol%, a variety of 21 differently substituted 2H-1,2,4-benzothiadiazine 1,1-dioxides can be prepared within 2 h. Moreover, the developed protocol gives access to the related 4H heterocycles. 相似文献
104.
Windhofer Karina Kari Alexander Prenninger Klaus Lange Stephan 《Forschung im Ingenieurwesen》2021,85(2):583-595
Forschung im Ingenieurwesen - Wind turbine noise used to be dominated by aerodynamic blade noise, effectively masking mechanical noise, originating from the drivetrain. Successful blade noise... 相似文献
105.
为提高风功率预测精度,减轻输出风能波动性对风电并网不利影响,提出了基于WT-IAGA-BP神经网络的短期风电功率预测方法。首先,利用风速分区、3σ准则及拉格朗日插值法清洗风电场历史数据;其次,依据小波重构误差,选择db4小波分别提取风速、风向、历史风功率的不同频率特征信号,并引入改进自适应遗传算法(IAGA)对各序列BP神经网络的初始权值与阈值寻优,使用Sigmiod函数通过适应度值自适应改变交叉概率与变异概率;最后,构建各序列的WT-IAGA-BP模型对短期风功率组合预测。通过仿真分析,并与ELM、WT-ELM及IAGA-BP方法对比,验证该方法具有更高的预测精度和更好的预测性能。 相似文献
106.
Chung-Chih Hung Changku Hwang Mohammed Ismail Kari Halonen Veikko Porra 《Analog Integrated Circuits and Signal Processing》1997,13(3):261-274
This paper presents two CMOS low-voltage rail-to-rail voltage-to-current converters (V-I converter) which could be used as basic building blocks to construct low-voltage current-mode analog VLSI circuits. In each of the circuits, an N-type V-I converter cell is connected in parallel with its P-type counterpart to achieve common-mode rail-to-rail operation. A linear differential relationship of the N-type V-I converter, or its P-type complement, is obtained using a new class-AB linearization technique. In the first rail-to-rail V-I converter circuit, a constant transconductance is achieved through the use of two maximum-current selecting circuits and an output subtraction stage. In the second circuit, a constant transconductance value is obtained by manipulating the DC bias currents of N- and P-type V-I converter cells. Both of the circuits can operate from rail to rail with a power supply of 3V, or less depending on the VLSI technology and the DC bias current level. 相似文献
107.
Väinö Hakkarainen Mikko Aho Lauri Sumanen Mikko Waltari Kari Halonen 《Analog Integrated Circuits and Signal Processing》2006,46(1):17-27
This article presents a 14-bit, 100-MS/s time-interleaved pipeline ADC, which samples input signal from 210-MHz IF-band. Digital self-calibration is employed to compensate gain mismatch and offset between time-interleaved channels as well as mismatches arise from a single ADC channel. A timing skew-insensitive parallel S/H circuit is utilized in order to avoid timing skew between parallel ADC channels. The ADC, fabricated in a 0.35-μm BiCMOS (SiGe) takes an area of 10.2 mm2, reaches an ENOB of 11.4 bits with a 79.9-dB SFDR at 192.5-MHz input and draws 1.4 W from a 3.0-V supply. 相似文献
108.
Mats Söderlund Päivi Mäki-Arvela Kari Eränen Tapio Salmi Risto Rahkola Dmitry Yu. Murzin 《Catalysis Letters》2005,105(3-4):191-202
Both thermal and catalytic decomposition of diborane resulting in borane as the main product were investigated under the pressure
and temperature ranges of 2–15 bar and 100–300 °C, respectively over Al2O3 and Pt/Al2O3 in a fixed bed reactor. Catalytic decomposition rate was essentially higher than the thermal decomposition, however the catalyst
deactivation was substantial. 相似文献
109.
110.