Purpose: To evaluate the association between tear mucin and dry eye, we compared tear fluid sialic acid concentration in dry eye patients with that in normal volunteers. We also compared the sialic acid concentrationw...Purpose: To evaluate the association between tear mucin and dry eye, we compared tear fluid sialic acid concentration in dry eye patients with that in normal volunteers. We also compared the sialic acid concentrationwith the results of several different types of dry eye examinations. Methods: Subjects comprised 16 age-matched, normal healthy controls and 45 dry eye patients. Dry eye examinations included fluorescein staining, rose bengal staining. Schirmer I test, cotton thread test, and fluorescein breakup time. Tear samples were collected with a micropipette after the instillation of 50 μ 1 saline. The sialic acid concentration was measured by high-performance liquid chromatography. Results: The sialic acid concentration was significantly lower in the dry eye group (5.3± 4.3 μ g/ml) than in the control group (37.1± 28.3 μ g/ml) (P < 0.001). Also, the sialic acid concentration correlated significantly with the results of dry eye examinations (P < 0.0002). Conclusions: The different sialic acid levels in the control and dry eyes may imply differences in the quantity or quality of glycoprotein in tears between these two groups. Thus, sialic acid, a component of mucin, may play a key role in the dry eye condition.展开更多
In this article,the effect of using water/zinc oxide nanofluid as a working fluid on the performance of solar collector is investigated experimentally.The volumetric concentration of nanoparticles is 0.4%,and the part...In this article,the effect of using water/zinc oxide nanofluid as a working fluid on the performance of solar collector is investigated experimentally.The volumetric concentration of nanoparticles is 0.4%,and the particle size is 40 nm,and the mass flow rate of the fluid varies from 1 to 3 kg/min.For this experiment,a device has been prepared with appropriate measuring instruments whose energy source is solar radiation.The solar energy absorbed by the flat plate collector is absorbed by the nanofluid of water/zinc oxide.The nanofluid is pumped to the consumer,a heat exchanger,where it heats the water.The temperature,radiation level,flow rate,and pressure in different parts of the device were measured.The pressure drop and the heat transferred are the most important results of this experimental work.The ASHRAE standard is used to calculate efficiency.The results showed that the use of water/zinc oxide nanofluid increases the collector performance compared to water.For 1 kg/min of mass flow rate,the nanofluids have a 16% increase in efficiency compared to water.From the results,it can be concluded that the choice of optimum mass flow rate in both water and nanofluid cases increases efficiency.展开更多
A novel vapor-liquid distributor was developed on the basis of sufficient study on the existing distributors applied in hydroprocessing reactors. The cold model test data showed that the fluid distribution performance...A novel vapor-liquid distributor was developed on the basis of sufficient study on the existing distributors applied in hydroprocessing reactors. The cold model test data showed that the fluid distribution performance of the novel vapor-liquid distributor was evidently better than the traditional one. Com- mercial tests of the new distributor were carded out in the 300 kt/a gas oil hydrotreating reactor at SINOPEC Changling Branch Company, showing that the new vapor-liquid distributor could improve the fluid distribution, promote the hydrotreating efficiency and lead to better performance than the traditional one.展开更多
文摘Purpose: To evaluate the association between tear mucin and dry eye, we compared tear fluid sialic acid concentration in dry eye patients with that in normal volunteers. We also compared the sialic acid concentrationwith the results of several different types of dry eye examinations. Methods: Subjects comprised 16 age-matched, normal healthy controls and 45 dry eye patients. Dry eye examinations included fluorescein staining, rose bengal staining. Schirmer I test, cotton thread test, and fluorescein breakup time. Tear samples were collected with a micropipette after the instillation of 50 μ 1 saline. The sialic acid concentration was measured by high-performance liquid chromatography. Results: The sialic acid concentration was significantly lower in the dry eye group (5.3± 4.3 μ g/ml) than in the control group (37.1± 28.3 μ g/ml) (P < 0.001). Also, the sialic acid concentration correlated significantly with the results of dry eye examinations (P < 0.0002). Conclusions: The different sialic acid levels in the control and dry eyes may imply differences in the quantity or quality of glycoprotein in tears between these two groups. Thus, sialic acid, a component of mucin, may play a key role in the dry eye condition.
文摘In this article,the effect of using water/zinc oxide nanofluid as a working fluid on the performance of solar collector is investigated experimentally.The volumetric concentration of nanoparticles is 0.4%,and the particle size is 40 nm,and the mass flow rate of the fluid varies from 1 to 3 kg/min.For this experiment,a device has been prepared with appropriate measuring instruments whose energy source is solar radiation.The solar energy absorbed by the flat plate collector is absorbed by the nanofluid of water/zinc oxide.The nanofluid is pumped to the consumer,a heat exchanger,where it heats the water.The temperature,radiation level,flow rate,and pressure in different parts of the device were measured.The pressure drop and the heat transferred are the most important results of this experimental work.The ASHRAE standard is used to calculate efficiency.The results showed that the use of water/zinc oxide nanofluid increases the collector performance compared to water.For 1 kg/min of mass flow rate,the nanofluids have a 16% increase in efficiency compared to water.From the results,it can be concluded that the choice of optimum mass flow rate in both water and nanofluid cases increases efficiency.
文摘A novel vapor-liquid distributor was developed on the basis of sufficient study on the existing distributors applied in hydroprocessing reactors. The cold model test data showed that the fluid distribution performance of the novel vapor-liquid distributor was evidently better than the traditional one. Com- mercial tests of the new distributor were carded out in the 300 kt/a gas oil hydrotreating reactor at SINOPEC Changling Branch Company, showing that the new vapor-liquid distributor could improve the fluid distribution, promote the hydrotreating efficiency and lead to better performance than the traditional one.
