Synthesis of hydroxyapatite crystals using carboxymethyl inulin for use as a delivery of ibuprofen

In the present study biodegradable, environmentally friendly polysaccharide-based polycarboxylate, carboxymethyl inulin (CMI), was used to produce hydroxyapatite (HAP) particles by wet chemical synthesis under controlled temperature, pH, and atmospheric conditions. The morphology and microstructure of the HAP nanoparticles were investigated by XRD, SEM, DTA–TGA and FTIR. CMI affects morphology, surface area, dimension and particle size distribution of the crystals. The reduction in size is greater in the direction of the c-axis. The increase in the polymer concentration to 7.5 g/L resulted in the mixture of nanoparticles with particle sizes of less than 100 nm. The SEM micrograph shows the formation of well-crystallized, agglomerated small particles of HAP. X-ray analysis has shown that the resulting particles have high thermal stability.The obtained crystals were used to produce tablets by direct compression of HAP. The influence of sample's CMI concentration on drug release profiles was investigated by using ibuprofen (C₁₃H₁₈O₂) as a model drug. The model was used to determine the effective diffusion coefficient of the drug from the tablets. A good agreement between experimental data and model predictions was obtained as calculated in the present work. The values of the diffusion coefficients range from 1.62 × 10^? 7 to 4.72 × 10^? 7 m² h^? 1.     

A Dynamic Maintenance Planning Framework Based on Fuzzy TOPSIS and FMEA: Application in an International Food Company

A maintenance planning framework is developed in this study to reduce and stabilize the maintenance costs of the manufacturing companies. The framework is based on fuzzy technique for order preference by similarity to ideal solution(TOPSIS) and failure mode and effects analysis (FMEA) techniques and supports maintenance planning decisions in a dynamic way. The proposed framework is general and can easily be adapted to a host of manufacturing environments in a variety of sectors. To determine the maintenance priorities of the machines, fuzzy TOPSIS technique is employed. In this regard, ‘risk priority number’ obtained by FMEA and ‘current technology’, ‘substitutability’, ‘capacity utilization’, and ‘contribution to profit’ are used as the criteria. Performance of the resulting maintenance plan is monitored, and maintenance priorities of the machines are updated by the framework. To confirm the viability of the proposed framework, a real‐world implementation in an international food company is presented. The results of the application reveal that the proposed maintenance planning framework can effectively and efficiently be used in practice. Copyright © 2015 John Wiley & Sons, Ltd.     

Effects of thermo‐fatigue loading,hydrostatic pressure,and heat aging on the free‐volume and crystalline structure of polypropylene‐co‐ethylene random copolymer pipes

Plastic pipes composed of polypropylene‐co‐ethylene random copolymers were subjected to accelerated aging by thermo‐fatigue loading (i.e., thermal cycling using hot and cold water alternately under pressure), application of hydrostatic pressure at elevated temperatures, and heat aging in an oven. The effects of these accelerated aging techniques on the molecular and crystalline structure of the material were investigated using positron annihilation lifetime spectroscopy, Fourier‐transform infrared spectroscopy, and differential scanning calorimetry. It was found that all three types of applied aging techniques decreased the size of the defects in the crystalline–amorphous interphase of the material, increased the density of these defects, and had a negligible impact on the free‐volume hole size and intensity of the amorphous phase. Thermo‐fatigue loading resulted in decreased lamellae thickness and lamellae thickness distribution; in contrast, hydrostatic pressure loading resulted in increased lamellae thickness and lamellae thickness distribution. The effect of thermo‐fatigue loading on the chemical degradation of polypropylene was more pronounced than the effects of hydrostatic pressure and heat aging. POLYM. ENG. SCI., 55:641–650, 2015. © 2014 Society of Plastics Engineers     

Dental Age Estimation Based on X-ray Images

Chronological age estimation using panoramic dental X-ray images is an essential task in forensic sciences. Various statistical approaches have proposed by considering the teeth and mandible. However, building automated dental age estimation based on machine learning techniques needs more research efforts. In this paper, an automated dental age estimation is proposed using transfer learning. In the proposed approach, features are extracted using two deep neural networks namely, AlexNet and ResNet. Several classifiers are proposed to perform the classification task including decision tree, k-nearest neighbor, linear discriminant, and support vector machine. The proposed approach is evaluated using a number of suitable performance metrics using a dataset that contains 1429 dental X-ray images. The obtained results show that the proposed approach has a promising performance.     

A fuzzy rule based expert system for stock evaluation and portfolio construction: An application to Istanbul Stock Exchange

The aim of this study is to construct appropriate portfolios by taking investor’s preferences and risk profile into account in a realistic, flexible and practical manner. In this concern, a fuzzy rule based expert system is developed to support portfolio managers in their middle term investment decisions. The proposed expert system is validated by using the data of 61 stocks that publicly traded in Istanbul Stock Exchange National-100 Index from the years 2002 through 2010. The performance of the proposed system is analyzed in comparison with the benchmark index, Istanbul Stock Exchange National-30 Index, in terms of different risk profiles and investment period lengths. The results reveal that the performance of the proposed expert system is superior relative to the benchmark index in most cases. Additionally, in parallel to our expectations, the performance of the expert system is relatively higher in case of risk-averse investor profile and middle term investment period than the performance observed in the other cases.     

Experimental investigations of air and liquid injection by venturi tubes

The venturi system creates a pressure differential that forms a vacuum. As water flows through the tapered venturi orifice, a rapid change in velocity occurs. This velocity change creates a reduced pressure (vacuum), which draws air and liquid to be injected into the system. The air and liquid injection rates vary with the pressure differential across the venturi. Typical applications of venturi tubes are for injecting fertilizers, chemicals, ozone gas, air or oxygen into pressurized water systems. In this paper, experimental studies were conducted to investigate the effects of inlet and throat diameters of the venturi tube, pipe length downstream of the venturi tube, diameter of the suction pipe at the throat portion of the venturi tube, angle of the pipe downstream of the venturi tube, flow velocity at the inlet portion of the venturi tube and density and viscosity of the liquid injected into the venturi tube on air and liquid injection rate. It was observed from the results that venturi tubes had high air and liquid injection efficiencies.     

LIQUEFACTION OF ELBI˙STAN AND YATAĞAN LIGNITES I N CARBON MONOXIDE/HYDROGEN GAS MIXTURES

Abstract

Thc effects of experimental parameters on the liquefaction yields of Elbistan and Yatagan lignites vcre investigated by using different solvents, guses and catalysts.

In hydroliquefaction of Elbistan lignite with anthracene and creosote oils, higher oil yields were obtained with anthracene oil. Based on this result, anthracene oil was chosen as solvent for further work done with Elbistan lignite. First the effect of moisture in lignite samples vas observed with synthesis gas as medium gas: then, the effect of carbon monoxide/ hydrogen ratio in liquefaction gas mixture was determined using moist lignite samples. The highest oil yield was obtained with moist lignite sample in 3CO/IH₂gas mixture and it was 57.3 % (daf).

The hydroliquefaction oil yields of Yatagan lignite obtained with creosote oil were higher than those obtained in anthracene ail. On Further work done with Yatagan lignite, creosote oil was chosen as solvent. First, the effects of CoMo and red mud catalysts, then in catalyzed medium, the effects of moisture in lignite samples and at last, using moist lignite samples and red mud catalyst. the effects o f carbon monaxide/hydrogen in synthesis gas medium and also, the increase in the oil yield a s an effect of catalyst presence, increased further: the 3CO/lH, ratio in gas medium was suitable for obtaining higher oil yields; and also for obtaining high oil yields, 440°c could be taken a s the most suitable temperature value and the pressure should be increased a s much as technical and economical conditions permit.     

Properties of aqueous salt solutions of poly(vinylpyrrolidone). II. Polymer dimensions and thermodynamic quantities

The unperturbed dimensions and thermodynamic parameters of poly(vinylpyrrolidone) (PVP) have been studied in aqueous salt solutions, e.g. phosphates, mono- and dihydrogen phosphates, carbonates, sulphates of sodium and potassium. Values of K₀ ( = [η]_ΘM^-1/2, where [η]_Θ is intrinsic viscosity at the theta temperature and M is molecular weight) with M_w = 78 000 g mol^-1 were found to range from 4·63×10^-4 to 5·56×10^-4 dl g^-1, and root-mean-square end-to-end distances, 〈r²〉₀^1/2, ranging from 1·61×10^-6 to 1·68×10^-6cm were evaluated. Values of the characteristic ratio, C_n, the steric parameter, σ, and the enthalpy and the entropy of dilution parameters, χ_H and χ_S, have also been calculated, and the interaction parameter was found to be χ-0·5<-0·001 for aqueous salt solutions of PVP. ©1997 SCI     

LIQUEFACTION OF ELB�STAN AND YATAĞAN LIGNITES I N CARBON MONOXIDE/HYDROGEN GAS MIXTURES

Thc effects of experimental parameters on the liquefaction yields of Elbistan and Yatagan lignites vcre investigated by using different solvents, guses and catalysts.

In hydroliquefaction of Elbistan lignite with anthracene and creosote oils, higher oil yields were obtained with anthracene oil. Based on this result, anthracene oil was chosen as solvent for further work done with Elbistan lignite. First the effect of moisture in lignite samples vas observed with synthesis gas as medium gas: then, the effect of carbon monoxide/ hydrogen ratio in liquefaction gas mixture was determined using moist lignite samples. The highest oil yield was obtained with moist lignite sample in 3CO/IH₂gas mixture and it was 57.3 % (daf).

The hydroliquefaction oil yields of Yatagan lignite obtained with creosote oil were higher than those obtained in anthracene ail. On Further work done with Yatagan lignite, creosote oil was chosen as solvent. First, the effects of CoMo and red mud catalysts, then in catalyzed medium, the effects of moisture in lignite samples and at last, using moist lignite samples and red mud catalyst. the effects o f carbon monaxide/hydrogen in synthesis gas medium and also, the increase in the oil yield a s an effect of catalyst presence, increased further: the 3CO/lH, ratio in gas medium was suitable for obtaining higher oil yields; and also for obtaining high oil yields, 440°c could be taken a s the most suitable temperature value and the pressure should be increased a s much as technical and economical conditions permit.