The article analyzes a shell and tube type condenser’s thermal performance using concepts of efficiency and effectiveness. Freon 134a is used as a coolant flowing through the shell. Water or water-based aluminum oxid...The article analyzes a shell and tube type condenser’s thermal performance using concepts of efficiency and effectiveness. Freon 134a is used as a coolant flowing through the shell. Water or water-based aluminum oxide nanoparticles are at relatively low saturation pressure in the tube. The condenser consists of 36 tubes divided into three central regions for analysis: superheated steam, saturated steam, and subcooled liquid. The three regions contain four tubes with three steps each, that is, 12 tubes. Region I, superheated steam, includes three horizontal baffles. Profiles of temperature, efficiency, and effectiveness are presented graphically for the three regions, with fixed refrigerant flow equal to 0.20 kg/s and fluid flow rate in the tube ranging from 0.05 kg/s to 0.40 kg/s. The experimental result for vapor pressure equal to 1.2 MPa and water flow equal to 0.41 kg/s was used as one of the references for the model’s physical compatibility.展开更多
Rate constants for the reaction of hydroxyl radicals with HFC 134a (CH 2FCF 3) have been measured by the discharge flow resonance fluorescence (DF RF) technique over the temperature range 288—370 K. The derived Arrhe...Rate constants for the reaction of hydroxyl radicals with HFC 134a (CH 2FCF 3) have been measured by the discharge flow resonance fluorescence (DF RF) technique over the temperature range 288—370 K. The derived Arrhenius equation is: k″ =(1.27±0.16)×10 -12 exp(-(1662±41)/ T )cm 3/(mol·s). The tropospheric lifetime of HFC 134a is estimated to be 10.5 years, which is in excellent agreement with the most recent results.展开更多
The discharge of large amounts of dye-containing wastewater seriously threats the environment.Adsorbents have been adopted to remove these dyes present in the wastewater.However,the high adsorption capacity,predominan...The discharge of large amounts of dye-containing wastewater seriously threats the environment.Adsorbents have been adopted to remove these dyes present in the wastewater.However,the high adsorption capacity,predominant pH-responsibility,and excellent recyclability are three challenges to the development of efficient adsorbents.The poly(acryloxyethyl trimethylammonium chloride)-graft-dialdehyde cellulose nanocrystals were synthesized in our work.Subsequently,the cationic dialdehyde cellulose nanocrystal cross-linked chitosan nanocomposite foam was fabricated via freeze-drying of the hydrogel.Under the optimal ratio of the cationic dialdehyde cellulose nanocrystal/chitosan(w/w)of 12/100,the resultant foam(Foam-12)possesses excellent absorption properties,such as high porosity,high content of active sites,strong acid resistance,and high amorphous region.Then,Foam-12 was applied as an eco-friendly adsorbent to remove acid red 134(a representative of anionic dyes)from aqueous solutions.The maximum dye adsorption capacity of 1238.1 mg∙g^(‒1) is achieved under the conditions of 20 mg∙L‒1 adsorbents,100 mg∙L^(‒1) dye,pH 3.5,24 h,and 25℃.The dominant adsorption mechanism for the anionic dye adsorption is electrostatic attraction,and Foam-12 can effectively adsorb acid red 134 at pH 2.5–5.5 and be desorbed at pH 8.Its easy recovery and good reusability are verified by the repeated acid adsorption–alkaline desorption experiments.展开更多
BACKGROUND Endoplasmic reticulum(ER)stress-related hepatocyte apoptosis is responsible for multiple hepatic diseases.Previous studies have revealed that endoplasmic reticulophagy(ER-phagy)promotes the selective cleara...BACKGROUND Endoplasmic reticulum(ER)stress-related hepatocyte apoptosis is responsible for multiple hepatic diseases.Previous studies have revealed that endoplasmic reticulophagy(ER-phagy)promotes the selective clearance of damaged ER fragments during ER stress,playing a crucial role in maintaining ER homeostasis and inhibiting apoptosis.Family with sequence similarity 134 member B(FAM134B)is a receptor involved in ER-phagy that can form a complex with calnexin(CNX)and microtubule-associated protein 1 light chain 3(LC3).The complex can mediate the selective isolation of ER fragments to attenuate hepatocyte apoptosis.However,the precise regulatory mechanisms remain unclear.AIM To elucidate the effect of FAM134B-mediated ER-phagy on ER stress-induced apoptosis in buffalo rat liver 3A(BRL-3A)rat hepatocytes and the potential regulatory mechanisms.METHODS ER stress-related hepatocyte apoptosis was induced using dithiothreitol(DTT).Proteins related to ER stress and autophagy were measured with western blotting.Protein complex interactions with FAM134B were isolated by co-immunoprecipitation.ER-phagy was evaluated in immunofluorescence experiments.Cell cycle distribution and apoptosis were measured by flow cytometry.Mitochondrial Ca^(2+) levels were evaluated by the co-localization of intracellular Ca^(2+)-tracker and Mitotracker.The small interfering RNA against FAM134B was used to knockdown FAM134B in BRL-3A cells.RESULTS ER stress-related and autophagy-related proteins in BRL-3A cells were elevated by both short and long-term DTT treatment.Furthermore,co-immunoprecipitation confirmed an interaction between FAM134B,CNX,FAM134B,and LC3 in BRL-3A cells.Immunofluorescence assays revealed that autolysosomes significantly decreased following short-term DTT treatment,but increased after long-term treatment.Mitochondrial Ca2+levels and apoptotic rates were dramatically elevated,and more cells were arrested in the G1 stage after short-term DTT treatment;however,these decreased 48 h later.Moreover,FAM134B downregulation accel展开更多
文摘The article analyzes a shell and tube type condenser’s thermal performance using concepts of efficiency and effectiveness. Freon 134a is used as a coolant flowing through the shell. Water or water-based aluminum oxide nanoparticles are at relatively low saturation pressure in the tube. The condenser consists of 36 tubes divided into three central regions for analysis: superheated steam, saturated steam, and subcooled liquid. The three regions contain four tubes with three steps each, that is, 12 tubes. Region I, superheated steam, includes three horizontal baffles. Profiles of temperature, efficiency, and effectiveness are presented graphically for the three regions, with fixed refrigerant flow equal to 0.20 kg/s and fluid flow rate in the tube ranging from 0.05 kg/s to 0.40 kg/s. The experimental result for vapor pressure equal to 1.2 MPa and water flow equal to 0.41 kg/s was used as one of the references for the model’s physical compatibility.
文摘Rate constants for the reaction of hydroxyl radicals with HFC 134a (CH 2FCF 3) have been measured by the discharge flow resonance fluorescence (DF RF) technique over the temperature range 288—370 K. The derived Arrhenius equation is: k″ =(1.27±0.16)×10 -12 exp(-(1662±41)/ T )cm 3/(mol·s). The tropospheric lifetime of HFC 134a is estimated to be 10.5 years, which is in excellent agreement with the most recent results.
基金This work was supported by the Natural Science Advance Research Foundation of Shaanxi University of Science and Technology(Grant No.2020XSGG-07)the Key Research and Development Program of Shaanxi Province(Grant No.2022GY-278)the Natural Science Basic Research Program of Shannxi(Program No.2023-JC-YB-104).
文摘The discharge of large amounts of dye-containing wastewater seriously threats the environment.Adsorbents have been adopted to remove these dyes present in the wastewater.However,the high adsorption capacity,predominant pH-responsibility,and excellent recyclability are three challenges to the development of efficient adsorbents.The poly(acryloxyethyl trimethylammonium chloride)-graft-dialdehyde cellulose nanocrystals were synthesized in our work.Subsequently,the cationic dialdehyde cellulose nanocrystal cross-linked chitosan nanocomposite foam was fabricated via freeze-drying of the hydrogel.Under the optimal ratio of the cationic dialdehyde cellulose nanocrystal/chitosan(w/w)of 12/100,the resultant foam(Foam-12)possesses excellent absorption properties,such as high porosity,high content of active sites,strong acid resistance,and high amorphous region.Then,Foam-12 was applied as an eco-friendly adsorbent to remove acid red 134(a representative of anionic dyes)from aqueous solutions.The maximum dye adsorption capacity of 1238.1 mg∙g^(‒1) is achieved under the conditions of 20 mg∙L‒1 adsorbents,100 mg∙L^(‒1) dye,pH 3.5,24 h,and 25℃.The dominant adsorption mechanism for the anionic dye adsorption is electrostatic attraction,and Foam-12 can effectively adsorb acid red 134 at pH 2.5–5.5 and be desorbed at pH 8.Its easy recovery and good reusability are verified by the repeated acid adsorption–alkaline desorption experiments.
基金Supported by National Natural Science Foundation of China,No.81560105Science and Technology Foundation of Guizhou Province,No.Qiankehe Jichu-ZK[2021]365,and No.Qiankehe Pingtai Rencai[2019]5801National Natural Science Foundation Cultivation Project of Guizhou Medical University,No.20NSP016。
文摘BACKGROUND Endoplasmic reticulum(ER)stress-related hepatocyte apoptosis is responsible for multiple hepatic diseases.Previous studies have revealed that endoplasmic reticulophagy(ER-phagy)promotes the selective clearance of damaged ER fragments during ER stress,playing a crucial role in maintaining ER homeostasis and inhibiting apoptosis.Family with sequence similarity 134 member B(FAM134B)is a receptor involved in ER-phagy that can form a complex with calnexin(CNX)and microtubule-associated protein 1 light chain 3(LC3).The complex can mediate the selective isolation of ER fragments to attenuate hepatocyte apoptosis.However,the precise regulatory mechanisms remain unclear.AIM To elucidate the effect of FAM134B-mediated ER-phagy on ER stress-induced apoptosis in buffalo rat liver 3A(BRL-3A)rat hepatocytes and the potential regulatory mechanisms.METHODS ER stress-related hepatocyte apoptosis was induced using dithiothreitol(DTT).Proteins related to ER stress and autophagy were measured with western blotting.Protein complex interactions with FAM134B were isolated by co-immunoprecipitation.ER-phagy was evaluated in immunofluorescence experiments.Cell cycle distribution and apoptosis were measured by flow cytometry.Mitochondrial Ca^(2+) levels were evaluated by the co-localization of intracellular Ca^(2+)-tracker and Mitotracker.The small interfering RNA against FAM134B was used to knockdown FAM134B in BRL-3A cells.RESULTS ER stress-related and autophagy-related proteins in BRL-3A cells were elevated by both short and long-term DTT treatment.Furthermore,co-immunoprecipitation confirmed an interaction between FAM134B,CNX,FAM134B,and LC3 in BRL-3A cells.Immunofluorescence assays revealed that autolysosomes significantly decreased following short-term DTT treatment,but increased after long-term treatment.Mitochondrial Ca2+levels and apoptotic rates were dramatically elevated,and more cells were arrested in the G1 stage after short-term DTT treatment;however,these decreased 48 h later.Moreover,FAM134B downregulation accel
