Loureirin B attenuates amiodarone-induced pulmonary fibrosis by suppression of TGFβ1/Smad2/3 pathway

Purpose: To investigate the therapeutic effect of loureirin B (LB) on amiodarone (AD)-induced pulmonary fibrosis (PF).Methods: Forty-eight male C57BL/6 mice, 8–10 weeks of age, were divided into four groups (n=12). Oral administration of amiodarone hydrochloride (AD) was performed for 4 weeks to induce pulmonary fibrosis. The degree of fibrosis was assessed by Masson staining, while collagen I and α-smooth muscle actin (α-SMA) levels were evaluated by Western blot analysis. ELISA was used to measure the levels of cytokines TNF-α, IL-1β, and IL-6 in bronchoalveolar lavage fluid (BALF) and lung tissue. Levels of p- Smad2, Smad2, p-Smad3 and Smad3 were determined by western blotting.Results: AD treatment increased the collagen levels and expression levels of collagen I and α-smooth muscle actin (α-SMA) in lung tissue and of inflammatory cytokines TNF-α, IL-1β, and IL-6, in both bronchoalveolar lavage fluid (BALF) and lung tissue in a dose-dependent manner (p < 0.01).Furthermore, AD increased the levels of p-Smad2/3. AD-induced increases in collagen I and α-SMA levels were reversed by loureirin B (LB). In addition, LB reduced AD-induced increased levels of the inflammatory cytokines TNF-α, IL-1β, and IL-6 in both bronchoalveolar lavage fluid (BALF) and lung tissue (p < 0.01).Conclusion: These results demonstrate that LB downregulates expression of fibrosis-related proteins and suppresses AD-induced PF. The  mechanism responsible for the protective effect of LB on ADinduced PF might involve inhibition of the Smad2/3 pathway. Thus, LB is a potential therapeutic agent for the management of PF. Keywords: Amiodarone, Loureirin B, Pulmonary fibrosis, Smad, Inflammatio

Optimization Study on Fluids for the Gravity-Driven Organic Power Cycle

The organic Rankine cycle (ORC) is efficient in using low-grade heat energy, while low pump efficiency and high pump leakage are usually serious problems. A gravity-driven organic power cycle (GDOPC) uses gravity instead of a pump to pressurize working fluid and has the potential to avoid problems associated with the pump. A theoretical method is used to study the performance and suitability of several fluids for GDOPC. The results show that the flow efficiency in high vertical pipes and the pump efficiency determine whether GDOPC gives better performance than ORC or not. When R245fa is selected as working fluid and evaporating temperature is 62 °C, specific energy of GDOPC (flow efficiency is 80%) is 2.5% higher than that of ORC (pump efficiency is 60%). The improvement degree of specific energy and the liquid column height increase with increasing evaporating temperature. R1234yf and R227ea give good performance with specific energy of 4.84 kJ/kg and 4.82 kJ/kg, respectively, while they need a liquid column as much as 76.55 m and 45.65 m, respectively. Although R365mfc and cyclopentane do not give the most excellent cycle performance, they need liquid column height as low as 9.04 m and 10.88 m, respectively. Fluid with low saturated pressure and high density may need low liquid column height and has the advantage to be used in practical applications

Investigation on the Pinch Point Position in Heat Exchangers

The pinch point is important for analyzing heat transfer in thermodynamic cycles. With the aim to reveal the importance of determining the accurate pinch point, the research on the pinch point position is carried out by theoretical method. The results show that the pinch point position depends on the parameters of the heat transfer fluids and the major fluid properties. In most cases, the pinch point locates at the bubble point for the evaporator and the dew point for the condenser. However, the pinch point shifts to the supercooled liquid state in the near critical conditions for the evaporator. Similarly, it shifts to the superheated vapor state with the condensing temperature approaching the critical temperature for the condenser. It even can shift to the working fluid entrance of the evaporator or the supercritical heater when the heat source fluid temperature is very high compared with the absorbing heat temperature. A wrong position for the pinch point may generate serious mistake. In brief, the pinch point should be founded by the iterative method in all conditions rather than taking for granted

Performance analysis of a zeotropicmixture (R290/CO_2) for trans-critical power cycle

Low critical temperature limits the application of CO 2 trans-critical power cycle. The binary mixture of R290 2 has higher critical temperature. Using mixture fluid may solve the problem that subcritical CO 2 is hardly condensed by conventional cooling water. In this article, theoretical analysis is executed to study the performance of the zeotropic mixture for trans-critical power cycle using low-grade liquid heat source with temperature of 200 °C. The results indicated that the problem that CO 2 can't be condensed in power cycle by conventional cooling water can be solved by mixing R290 to CO 2 . Variation trend of outlet temperature of thermal oil in supercritical heater with heating pressure is determined by the composition of the mixture fluid. Gliding temperature causes the maximum outlet temperature of cooling water with the increase of mass fraction of R290. There are the maximum values for cycle thermal efficiency and net power output with the increase of supercritical heating pressure

Optimization of the self-condensing CO2 transcritical power cycle using solar thermal energy

Compared with the conventional Rankine cycle, the CO2 transcritical power cycle gives a higher thermal efficiency because of its high average heat absorbing temperature and is suitable for driving a compact system. The self-condensing CO2 transcritical power cycle can solve the problem that CO2 is difficult to condense in a conventional CO2 transcritical power cycle using conventional water cooling. Based on solar thermal energy, a theoretical analysis model was established to study the relationship between the cycle performance and the operating parameters. The results showed that the thermal efficiency increases with increasing the cooled pressure with a low final cooled temperature. By increasing the final cooled temperature, a peak appears on the thermal efficiency curve. The outlet temperature of the cooling water is affected by a shift of the pinch point position in the cooler. According to the variation of the outlet temperature of the cooling water and the proportion of the mass flow rate of CO2 in the power sub-cycle and that in the whole cycle, it can be concluded that conditions with a very low cooled pressure are uncontrollable. In these conditions, the maximum thermal efficiency of the self-condensing CO2 transcritical cycle is 0.3463, which is 0.0313 a little lower than that of the supercritical CO2 Brayton cycle. However, the novel cycle simplifies the development of the pressurizing component and avoids the liquid hammer in the pressurizing process

Experimental Investigation on the Performance of [APMIm][NTf2] for Capturing CO2 from Flue Gas of the Cement Kiln Tail

Facing the global warming trend, humanity has been paying more and more attention to the Carbon Capture, Utilization and Storage. Large amounts of CO2 is emitted with burning fossil fuel as well as by some special industrial processes like the decomposition of calcium carbonate in a cement plant. The cement industry contributes about 7% of the total worldwide CO2 emissions and the CO2 concentration of flue gas of the cement kiln tail even exceeds 30%. Ionic liquid is considered to be an effective and potential material to capture CO2. In order to investigate the performance of ionic liquids for capturing CO2 from flue gas of the cement kiln tail, an experiment system was established and an ionic liquid, [APMIm][NTf2] (1-aminopropyl-3-imidazolium bis(trifluoromethylsulfonyl)imine), was tested using pure CO2 and simulated gas. The results showed that both physical and chemical absorption play roles while physical absorption dominates in the absorption process. Both the absorption capacity and rate decrease with raising the operating temperature. In the experiment with pure CO2, the absorption capacity is 0.296 mol(CO2).mol(IL)(-1) at 30 degrees C and 0.067 molCO(2).mol(IL)(-1) at 70 degrees C. Meanwhile, the ionic liquid can be regenerated for recycling without obvious changes of the absorption capacity. When the ionic liquid is used for flue gas of the cement kiln tail rather than pure CO2, a sharp decrease of the absorption capacity and rate was observed obviously. The absorption capacity at 30 degrees C dropped even to 0.038 mol(CO2).mol(IL)(-1), 12.8% of that for pure CO2. Additionally, a natural desorption of CO2 from the ionic liquid was observed and affected the experimental results of the absorption capacity and the absorption-desorption rate to some extent

Starting and running performance of a pulsating heat pipe with micro encapsulated phase change material suspension

Pulsating heat pipe (PHP) is an efficient heat transfer technology. The micro encapsulated phase change material (MEPCM) suspension is a novel latent heat fluid with high heat storage density. The research on the PHP with MEPCM suspension is of great significance for expanding the types of working fluids and studying the operating performance. An experimental investigation of starting and running performance was carried out on a closed loop PHP with MEPCM suspension at mass concentration of 0.5%. The results show that the PHP charged with MEPCM suspension starts unstably with irregular oscillating under lower heating power of 30-90 W, while it runs stably after starting with heating power increasing to 120 W. The start-up time of PHP charged with MEPCM suspension first drops rapidly, then flattens from 50 s to 20 s with increasing heating power and it still maintains at 20 s with the increasing of heating power from 150 W during experiments, which indicates the influence on the start-up time from further increasing heating power becomes smaller on the condition that the heating power increases to a certain level. Compared with 70% of filling ratio, conditions with 35% and 50% of that showed better performance. Gravity is very important to overcome the viscous resistance of working fluids. The running performance of PHP was slightly affected by inclination angle which was greater than 60 degrees. When it dropped to 30 degrees, the running deteriorated obviously. However, the PHP with 35% of filling ratio couldn't run normally at a small inclination angle of 30 degrees

Experimental Investigation of the Operating Characteristics of a Pulsating Heat Pipe with Ultra-Pure Water and Micro Encapsulated Phase Change Material Suspension

The specific heat capacity of working fluid is an important influence factor on heat transfer characteristic of the pulsating heat pipe (PHP). Due to the relatively large specific heat capacity of micro encapsulated phase change material (MEPCM) suspension, a heat transfer performance experimental facility of the PHP was established. The heat transfer characteristic with MEPCM suspension of different mass concentrations (0.5% and 1.0%) and ultra-pure water were compared experimentally. It was found that when the PHP uses MEPCM suspension as its working fluid, operating stability is impoverished under lower heating power and the operating stability is better under higher heating power. At the inclination angle of 90 degrees, the temperature at heating side decreases compared to ultra-pure water and the temperature at heating side decreases with the raising of MEPCM suspension mass concentration. The heat transfer characteristic of the PHP is positively correlated with the inclination angle and the 90 degrees is optimum. The unfavorable effect of the inclination angle decreases with heating power increasing. When the inclination angle is 90 degrees, the PHP with MEPCM suspension at 1.0% of mass concentration has the lowest thermal transfer resistance and followed by ultra-pure water and MEPCM suspension at 0.5% of mass concentration has the highest thermal transfer resistance. When the inclination angles are 60 degrees and 30 degrees, the effect of gravity on the flow direction is reduced to 86.6% and 50% of that on the inclination angle of 90 degrees, respectively, and the promoting effect of gravity on the working fluid is further weakened as the inclination angle further decreases. Due to the high viscosity of MEPCM suspension, the PHP with ultra-pure water has the lowest heat transfer resistance. When the inclination angles is 60 degrees, the thermal resistance with MEPCM suspension at 0.5% of the mass concentration is lower than that at 1.0% at the heating power below 230 W. The thermal resistance of MEPCM suspension tends to be similar for heating power of 230-250 W. At the heating power above 270 W, the thermal resistance with MEPCM suspension at 1.0% of the mass concentration is lower than that at 0.5%