Search

Gas sweetening with an aqueous solution of diethanolamine is a crucial and common process in natural gas processing. However, the process, particularly in the solvent regeneration section, consumes a substantial amount of energy, significantly escalating the cost of gas. This paper presents a simulation and optimization of an existing natural gas refinery plant using a lean vapor compression method. The simulation results indicate that the current process requires 2.73 GJ/tacid gas for solvent regeneration, with exergy destruction of 14,120.59 kW in the solvent regeneration section. The total annualized cost for the current process is 11.68 M$. A modified scheme is proposed to address the issue of high energy consumption and the associated costs. The proposed scheme demonstrates significant improvements in the aforementioned parameters. Specifically, energy for solvent regeneration, exergy destruction in the solvent regeneration section, total annualized cost, and cost of gas are reduced by 16.12 %, 25.04 %, 20.97 %, and 20 % compared to the current process, respectively. These improvements enhance the thermoeconomic indexes, making the proposed scheme a viable and cost-effective alternative to the current process. [ABSTRACT FROM AUTHOR]

Abstract: Secreted protein acidic and rich in cysteine (SPARC) is a secretory multifunctional matricellular glycoprotein. High circulating levels of SPARC have been reported to be associated with obesity and insulin resistance. The aim of the present study was to investigate whether SPARC induces insulin resistance and mitochondrial dysfunction in adipocytes. Our results showed that feeding high fat diet to rats for 12 weeks significantly increased SPARC expression in adipose tissues at both mRNA and protein levels. Moreover, SPARC overexpression in stably transfected 3T3-L1 cells induced insulin resistance and mitochondrial dysfunction, as evidenced by inhibition of insulin-stimulated glucose transport, lower ATP synthesis and mitochondrial membrane potential, reduced expression of glucose transporter 4 (GLUT4), and increased levels of reactive oxygen species (ROS) in mature adipocytes. Finally, overexpression of SPARC also modulated the expression levels of several inflammatory cytokines, which play important roles in insulin resistance, glucose and lipid metabolism during adipogenesis. In conclusion, our data suggest that SPARC is involved in obesity-induced adipose insulin resistance and may serve as a potential target in the treatment of obesity and obesity-related insulin resistance. [Copyright &y& Elsevier]

Abstract: Ag-MnOx/C composites were prepared using AgNO3 and KMnO4 as the precursors and Vulcan XC-72 as the support. The physical properties of the Ag-MnOx/C composites were investigated via X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS) and transmission electron microscopy (TEM). The activity and the stability of the series of Ag-MnOx/C composites toward the oxygen reduction reaction (ORR) in alkaline media were investigated through the electrochemical techniques. The results show that the main species MnO2 and Ag2O in the fresh sample convert into Mn3O4 and Ag(0), respectively, after the heat treatment in N2 at 300°C (Ag-MnOx/C-300). The Ag-MnOx/C-300 sample shows the highest activity toward the ORR, with the half-wave potential of the ORR shifting negatively only 0.035V compared to that on the commercial 40wt. % Pt/C (JM). The electron transfer number during the ORR on the Ag-MnOx/C composite increases with the value close to four after the heat treatment at 300°C, which is mainly attributed to the formation of Ag(0), rather than Mn3O4. The heat treatment brings about a better catalytic stability of the composite, and no obviously negative shift takes place for the half-wave potential of the ORR on the Ag-MnOx/C-300 composite after 1000 cycles accelerated aging test. The maximum power density of the zinc-air battery with the Ag-MnOx/C-300 air electrode reaches up to 130 mW cm−2, higher than those based on the Pd/C and Pt/C cathode catalysts, which shows that the Ag-MnOx/C-300 composite is a promising candidate as the catalyst for the air electrode. [Copyright &y& Elsevier]

• A noble-metal-free g-C 3 N 4 /α-Ni(OH) 2 is fabricated through hydrothermal method. • α-Ni(OH) 2 promotes the adsorption and activation of O 2 and oxygen atoms. • g-C 3 N 4 /α-Ni(OH) 2 reveals excellent photocatalytic NO removal without NO 2 generation. • This find provides a fresh insight for the control of toxic byproduct. Photocatalytic NO x removal is regarded as a promising technique for air purification in recent years. However, NO x removal process usually accompanies with toxic NO 2 generation, leading to serious secondary pollutant and limiting its practical application. Herein, a noble-metal-free g-C 3 N 4 /α-Ni(OH) 2 photocatalyst was fabricated through hydrothermal method. The introduction of α-Ni(OH) 2 microspheres combines with g-C 3 N 4 , resulting in an enlarged surface area from 35 to 95 m2/g, while the unique structure of α-Ni(OH) 2 broadens visible-light response range and accelerates photogenerated charge carriers transfer. More importantly, the H atoms of α-Ni(OH) 2 improve the adsorption and activation of O 2 and oxygen atoms to promote NO and NO 2 oxidized to nitrate. Consequently, g-C 3 N 4 /α-Ni(OH) 2 shows enhanced NO removal ratio of 51.3% without any toxic NO 2 generation, indicating its great potential for air purification. Our results provide fresh insight into the design of highly efficient and safe photocatalyst for toxic byproduct control in the application of environmental remediation. [ABSTRACT FROM AUTHOR]

Background: Several studies have indicated an association between tumor necrosis factor-alpha (TNF-α) or interleukin (IL)-6 gene polymorphisms and lung cancer risk. However, the conclusions remain controversial., Methods: An English literature screening about case-control trials with regard to TNF-α (-308G/A) or IL-6 (174G/C) polymorphisms and lung cancer susceptibility was performed on PubMed, EMBASE, and EBSCO until November 2012. The pooled odds ratio (OR) and 95% confidence intervals (CI) were calculated using STATA 11.0. Sensitivity analysis was performed by sequential omission of individual studies. Publication bias was evaluated by Egger's linear regression test and funnel plots., Results: Eight eligible studies, including 1,690 patients and 1,974 controls, were identified in this meta-analysis. Compared with the control, no significant association was revealed between TNF-α-308G/A (GG + GC vs. CC: OR = 1.10, 95% CI: 0.73 to 1.64; GG vs. GC + CC: OR = 1.02, 95% CI: 0.81 to 1.27; GC vs. CC: OR = 1.13, 95% CI: 0.73 to 1.77; GG vs. CC: OR = 1.04, 95% CI: 0.80 to 1.36; G vs. C: OR = 1.03, 95% CI: 0.90 to 1.18) or IL-6 174G/C (GG + GC vs. CC: OR = 1.10, 95% CI: 0.73 to 1.64; GG vs. GC + CC: OR = 1.02, 95% CI: 0.81 to 1.27; GC vs. CC: OR = 1.13, 95% CI: 0.73 to 1.77; GG vs. CC: OR = 1.04, 95% CI: 0.80 to 1.36; G vs. C: OR = 1.03, 95% CI: 0.90 to 1.18) and lung cancer risk. The pooled OR remained unchanged after removing the maximum-weight study and no publication bias was observed., Conclusions: The study raises the possibility of no correlation between the polymorphisms of the two genes and lung cancer susceptibility. However, further researches with large-sample or subgroup analyses are necessary to validate the conclusions.