Influence of the protocol of fibroin extraction on the antibiotic activities of the constructed composites

The effect of the solvents for silk fibroin (SF) extraction on its antimicrobial activity was studied. Extraction protocols were performed using LiBr (SF(L)) and Ajisawa’s reagent (CaCl(2):ethanol:H(2)O) (SF(C)). The morphological and structural characteristics of the extracted SF and their composites were assessed. Corresponding bactericidal activities against Staphylococcus aureus (ATCC 25923), Escherichia coli (ATCC 25922) and Pseudomonas aeroginosa (ATCC 27853) were performed. The resulting solutions were either casted into films or individually incorporated into composites of silver nanoparticles (NS) embedded into chitosan fragments (Cs) through γ-irradiation. Films of SF, obtained by using the two solvents, as well as the final prepared composites of SF, NS and Cs were analyzed using XRD, FTIR, SEM, TEM and zeta potential at several pH values. The band gap values were calculated. The results proved that, although SF(C) consumed shorter gelation time, yet SF(L) exerted higher antibiotic activity against the tested microorganisms. Moreover, the final composites had the ability to significantly reduce the growth of these medically relevant bacteria and are, therefore, recommended as a novel natural antibacterial biomaterial for several biomedical applications

Active distribution networks planning with integration of demand response

YesThis paper proposes a probabilistic method for active distribution networks planning with integration of demand response. Uncertainties related to solar irradiance, load demand and future load growth are modelled by probability density functions. The method simultaneously minimizes the total operational cost and total energy losses of the lines from the point of view of distribution network operators with integration of demand response over the planning horizon considering active management schemes including coordinated voltage control and adaptive power factor control. Monte Carlo simulation method is employed to use the generated probability density functions and the weighting factor method is used to solve the multi-objective optimization problem. The effectiveness of the proposed method is demonstrated with 16-bus UK generic distribution system

A Theoretical Study of Feasibility of Alternating Engine

This study is an evaluation of a new idea of an engine Alternating Engine which should have lower mechanical losses, less vibration, higher mechanical efficiency and more torque than the conventional reciprocating engine. The name of Alternating engine came from the alternating parts pistons in a circle instead of reciprocating parts as in conventional engine. The Alternating engine has lower mechanical losses due to no inertia forces of the reciprocating parts as in the conventional engine that include pistons and connecting rods during a complete combustion cycle. Less vibration is due to a complete balance for the alternating parts. Higher torque at very low RPM is due to longer torque arm than the conventional crank shaft torque arm. The thermodynamic analysis in this study used an ideal gas model (air) for the working fluid. Sealing the sliding surfaces and parts remains a significant challenge but is not as challenging if compared to the Wankel engine

The Effect Of Vapor Grown Carbon Nanofiber-Modified Alkyd Paint Coatings On The Corrosion Behavior Of Mild Steel

Organic coatings are extensively used as protective coatings in several industries including the automotive and aircraft industries. The last few years have witnessed an increased interest in improving not only the mechanical properties but also the corrosion protection properties of organic coatings. Among the currently investigated methods of improving the performance of organic coatings is the incorporation of additives in the organic paint matrix. Vapor grown carbon nanofibers (VGCNFs) are a class of carbon fibers that are produced by catalytic dehydrogenation of a hydrocarbon at high temperatures. Depending on the method of synthesis and the post-treatment processes, the diameter of the VGCNFs is normally in the 10-300 nm range. The small size, light weight, high aspect ratio, and unique physical, thermal, mechanical, and electrical properties of VGCNF make it an ideal reinforcing filler in polymer matrix nanocomposites to enhance the mechanical properties of the pure polymeric material in high performance applications in several industries such as the automotive, aircraft, battery, sensors, catalysis, electronics, and sports industries. The main objective of the current investigation was to study the corrosion protection offered by the incorporation of VGCNFs into a commercial alkyd paint matrix applied to the surface of mild steel coupons. The corrosion protection was investigated by immersing samples in air saturated 3% NaCl solution (artificial seawater). The samples were studied by electrochemical impedance spectroscopy (EIS) along with other measurements, including electrochemical (open circuit potential, cyclic voltammetry), chemical (salt spray test), electrical conductivity, and surface analysis (SEM, AFM, optical profilometry, and nanoindentation). The study involved the investigation of the effect of the weight percent (wt %) of the VGCNF as well as the coating film thickness on the corrosion protection performance of the coated steel samples when exposed to the corrosive electrolyte. By way of contrast, the EIS behavior of steel coupons coated with a paint coating incorporating different weight percents of powdered silicon carbide (SiC) particles was also studied. The EIS spectra were used to calculated and graph several corrosion parameters for the investigated systems. At the end, the studied coatings were ranked in order of their anticorrosive properties

Bringing Biophilic Architecture into Business Parks Design Towards Enhancing Users Experience

Recently, most people have spent much of their time at work, often in indoor office buildings that are designed without regard to natural elements and workers` well-being. For these reasons, Business Parks are designed to improve the whole workplace environment. Bringing fresh air, green areas, and natural elements into workspaces could enhance the work environment and increase productivity by taking care of workers` physiological needs. On other hand, Biophilic design introduces some principles to create visually beautiful and spiritual places. By merging Architecture with nature and bringing outdoors greenery through indoor areas, a healthy workplace environment could be generated. Therefore, Biophilic design could be a solution towards more relaxed workspaces. Consequently, this study will elaborate a comprehensive framework towards combining principles, attributes, and elements of Biophilic design and design solutions of Business Parks. The study focuses on Business Park as a case study as the trend of Business Park can change the traditional concept of office buildings and reconnect the human with nature again, which lessens stress and negative impacts on health. So that, workers can get a work environment free from stress which will enhance the individuals` well-being. In this context, this paper will analyze international, local offices and Business Parks that were designed upon Biophilic design concepts. Eventually, the novelty aim of this manuscript is to create a contemporary tendency which concerns about blending the Biophilic design concept with Business Parks interior and exterior design spaces to create an efficient and healthy work environment, also to improve the whole users` experience

ロングゲージカーボンセンサを用いたコンクリート構造物の鉄筋腐食モニタリングに関する研究

茨城大学博士（学術）application/pdfapplication/pdftext/plain学位論文(Thesis)2016doctoral thesi

The Effect Of Vapor Grown Carbon Nanofiber-Modified Alkyd Paint Coatings On The Corrosion Behavior Of Mild Steel

Organic coatings are extensively used as protective coatings in several industries including the automotive and aircraft industries. The last few years have witnessed an increased interest in improving not only the mechanical properties but also the corrosion protection properties of organic coatings. Among the currently investigated methods of improving the performance of organic coatings is the incorporation of additives in the organic paint matrix. Vapor grown carbon nanofibers (VGCNFs) are a class of carbon fibers that are produced by catalytic dehydrogenation of a hydrocarbon at high temperatures. Depending on the method of synthesis and the post-treatment processes, the diameter of the VGCNFs is normally in the 10-300 nm range. The small size, light weight, high aspect ratio, and unique physical, thermal, mechanical, and electrical properties of VGCNF make it an ideal reinforcing filler in polymer matrix nanocomposites to enhance the mechanical properties of the pure polymeric material in high performance applications in several industries such as the automotive, aircraft, battery, sensors, catalysis, electronics, and sports industries. The main objective of the current investigation was to study the corrosion protection offered by the incorporation of VGCNFs into a commercial alkyd paint matrix applied to the surface of mild steel coupons. The corrosion protection was investigated by immersing samples in air saturated 3% NaCl solution (artificial seawater). The samples were studied by electrochemical impedance spectroscopy (EIS) along with other measurements, including electrochemical (open circuit potential, cyclic voltammetry), chemical (salt spray test), electrical conductivity, and surface analysis (SEM, AFM, optical profilometry, and nanoindentation). The study involved the investigation of the effect of the weight percent (wt %) of the VGCNF as well as the coating film thickness on the corrosion protection performance of the coated steel samples when exposed to the corrosive electrolyte. By way of contrast, the EIS behavior of steel coupons coated with a paint coating incorporating different weight percents of powdered silicon carbide (SiC) particles was also studied. The EIS spectra were used to calculated and graph several corrosion parameters for the investigated systems. At the end, the studied coatings were ranked in order of their anticorrosive properties

Adiponectin could be a comprehensive marker of metabolic syndrome in obese children

Objectives: The objectives were to investigate the relationship between the serum adiponectin level and the metabolic syndrome (MS) phenotype in children, and to examine the independent association between the serum adiponectin level and the individual components of MS.Design: A cross-sectional design was used.Subjects: Fifty-six obese children with a body mass index ≥ 95th percentile for age and sex, and 50 normal-weight children matched for age and sex with the obese children, were used as controls.Outcome measures: The main outcome measure was the serum adiponectin level.Results: The serum adiponectin level was significantly lower in obese children, than in the normal-weight controls (7.35 ± 3.1 μg/dl vs. 10.64 ± 3.04 μg/dl). Obese children with MS have a significantly lower serum adiponectin level compared to obese children without MS (5.92 ± 1.9μg/dl vs. 8.57 ± 2.1 μg/dl). There was a significant negative correlation between the serum adiponectin level and waist circumference, triglyceride levels, systolic blood pressure, diastolic blood pressure, and fasting blood glucose. The serum adiponectin level correlated positively with the level of high-density lipoprotein cholesterol. After controlling for the confounding effect of age, sex and visceral fat, the adiponectin level remained a significant predictor of the MS [odds ratio (OR): 0.76, 95% CI: 0.63-0.91].Conclusion: Adiponectin demonstrated a consistent relationship to each MS component. Adiponectin may be a comprehensive marker of the MS condition