bluuebunny/crossref_metadata_2025 huggingface dataset:
Hydrodynamically-Enhanced Light Intensity Distribution in an Externally-Irradiated Novel Aerated Photoreactor: CFD Simulation and Experimental Studies
Authors: Trujillo Francisco J , Lee Ivy A-L , Hsu Chen-Han , Safinski Tomasz , Adesina Adesoji A
Published: July 2008

The enhancement of the surface incident radiation on the walls of an externally-irradiated bubble tank photoreactor was studied and modeled by solving the radiation transport equation (RTE) in conjunction with the continuity, momentum and k-e turbulence equations. Computational fluid dynamic (CFD) simulation results were complemented with actinometric runs to determine the effect of the gas flow rate on the radiation loss by reflection at the surface of the gas-liquid mixture due to bursting of the bubbles. The model assumed that the gas-liquid mixture is a semitransparent medium where the light is scattered as a result of specular reflection and refraction when the light rays impinge on the air bubbles. The superficial reflectivity at the top of the gas-liquid mixture was linearly correlated with the superficial gas velocity. In particular, the simultaneous solution of the hydrodynamics and radiation transport equation using CFD allowed us to establish the relationship between the light scattering coefficient and the bubble size and the gas hold-up. The excellent agreement obtained between the experimental data and the CFD model validates the proposed model.
Experimental Investigations on the Effect of the Tracer Location on Mixing in a Spout-Fluid Bed
Authors: Zhang Yong , Jin Baosheng , Zhong Wenqi
Published: July 2008

Experimental investigations on the mixing behavior of a spherical particle in a spout-fluid bed with a cross section of 0.1 m×0.03 m and height of 0.5 m were carried out. The image processing technology and bed-frozen method were employed to measure the axial and radial concentration of the tracer at different times. Four various initial conditions (top, side, bottom and middle loading) were used to examine the influence of the tracer location on the mixing. In addition, the underlying mixing mechanisms were preliminarily discussed in terms of the evolution of the mixing index. It is shown that the initial tracer location affects the initial mixing rate but not the final mixing degree. The top and bottom loading cases characterised by dominant axial mixing perform significantly better than the side loading case characterised by dominant radial mixing. Due to the axial rapid convection and radial intense diffusion, the mixing speed for a middle loading case is much faster compared to other cases. The results also demonstrate that the convection caused by the circulation and diffusion among the circulation rolls are two main mixing mechanisms in a spout-fluid bed.
Letter: Zombies May Mean Attention Bonds Will Not Cure Spam
Authors: Lim Jamus Jerome
Published: July 2008

Marshall van Alstyne's recent article makes a strong case for attention bonds as a Coasean-based solution to the spam problem. Unfortunately, zombies and trojan horses may make it infeasible.
Letter: Why Are Economists Indeed So Unscientific?
Authors: Sällström Matthews Susanna
Published: July 2008

This letter provides an answer to the question raised by David Heigham as to why economists are so unscientific.
Letter: Two Paise and Trust
Authors: Correa Romar
Published: July 2008

Low-denomination coins are ceasing to be accepted as a medium of exchange in India, according to Romar Correa.
The Emperor's Dangerous Clothes
Authors: Kotlikoff Laurence J
Published: July 2008

Laurence Kotlikoff argues that the official United States deficit does not look too terrible, but it is a terrible measure of the government's economic health: The truth is a $70 trillion long run imbalance that is growing at $2 trillion per year.
Microsoft: Predator or Prey?
Authors: Hahn Robert , Passell Peter
Published: July 2008

The European Commission is still after Microsoft, but the competition has gotten there first according to Robert Hahn and Peter Passell.
Letter: What Economists Can Contribute to the Global Warming Debate
Authors: Rasmusen Eric Bennett
Published: July 2008

Eric Rasmusen presents a global warming research agenda for economists.
Increasing Research Literacy and Capacity in Massage Therapy: Investigating the Feasibility of a Peer-Reviewed International, Electronic Massage Therapy Journal
Authors: Hodgson Pamela , Dryden Trish , Finch Paul , White Marc
Published: July 2008

Research literacy and research capacity are underdeveloped within the massage therapy community. A potential vehicle to increase research literacy and capacity could be a peer-reviewed, international electronic massage therapy journal. This article reports on a feasibility study and strategic planning meeting. Participants from the scientific and professional communities concluded that despite significant challenges, there might be sufficient academic interest and professional backing to support a collaborative massage therapy e-journal.
Cardiovascular and Anti-Platelet Aggregation Activities of Extracts from Solanum torvum (Solanaceae) Fruits in Rat
Authors: Nguelefack Télesphore Benoît , Mekhfi Hassane , Dimo Théophile , Afkir Saida , Nguelefack-Mbuyo Elvine Pami , Legssyer Abdelkaleq , Ziyyat Abderrahim
Published: July 2008

The present work evaluates the cardiovascular activity of the aqueous (AES) and methanol (MES) extracts from S. torvum fruits. The anti-platelet aggregation activity of the AES was also evaluated on platelets isolated from rats. Intravenous administration of AES and MES induced a significant reduction in arterial blood pressure. The intravenous administration of AES at the doses of 1 and 2 mg/kg did not affect the heart rate. In contrast to AES, MES reduced the heart rate at all the doses (1, 2 and 5 mg/kg). Neither atropine (1 mg/kg) nor yohimbine (1 mg/kg) significantly affects the hypotensive activity of AES. Yohimbine almost completely inhibited the cardiac effect of AES. L-NAME (20 mg/kg) significantly potentiated the hypotensive and the cardiac effects of AES. When essayed on the platelet aggregation, induced by either thrombin (0.5 U/ml) or Adenosine diphosphate (5 µM), AES significantly and dose dependently inhibited the aggregation induced by both agents. MES and AES possess hypotensive activity which may partially result from their bradycardic effect. The anti-platelet aggregation effect of AES may be a benefit for its cardiovascular effect. These results support the use of the plant in the treatment of arterial hypertension and haemostatic ailments.
The Antioxidant Defense System Induced by Methanol Extract of Careya arborea in N-Nitroso-diethylamine (NDEA) Induced Hepatocarcinogenesis
Authors: Sambath Kumar Ramanathan
Published: July 2008

The methanol extract of stem barks of Careya arborea Roxb (MECA) (Family- Myrtaceae) was evaluated against hepatocellular carcinoma induced by N-nitrosodiethylamine (NDEA). NDEA is a widely used experimental tool to induce cancer in animals causing oxidative stress and cellular injury due to the enhanced formation of free radicals and is associated with rise in biochemical parameters like serum glutamyl pyruvate transaminase (SGPT), serum glutamyl oxalacetic acid (SGOT), serum alkaline phosphatase (SALP), bilirubin, as well as decrease in the levels of total protein and uric acid. Furthermore, the protective effect of Careya arborea against perturbations in the levels of antioxidant defense system was also estimated. The MECA was administered at the doses of 100 and 200 mg/kg body weight/rat in alternative days for 8 weeks. At the end of the drug schedule, rats were sacrificed and the effect of MECA on visible macroscopic (Morphometry) liver lesion (neoplastic nodules) and the level of SGPT, SGOT, SALP, bilirubin, total protein, uric acid and liver antioxidant defense parameters like lipid peroxidation (LPO), nonenzymatic antioxidant such as glutathione content (GSH), vitamin C, vitamin E and enzymatic antioxidant like superoxide dismutase (SOD) and catalase (CAT) were estimated. The MECA was found to be protective against NDEA-induced carcinoma by decreasing the activity of serum enzymes, bilirubin and increase the protein and uric acid levels. MECA significantly decreased the levels of LPO, while it significantly increased the levels of GSH, vitamin C, vitamin E, SOD and CAT. The results indicate that MECA exhibited significant chemopreventive effects by suppressing nodules development and enhancing the antioxidants in NDEA carcinogenesis by reducing the formation of free radicals.
A Load Modeling Method Based on Wide Area Trajectory Sensitivity
Authors: Guan Xiupeng , Sun Yuanzhang , Cheng Lin
Published: July 2008

A load modeling method based on wide area trajectory sensitivity of a power system is presented in this paper. A generator angle as wide area information is used to identify load parameters. Load parameters of wide area identification can fit the dynamic behaviors of a power system more accurately than that of local identification can. Compared with the local-sensitivity of the load parameter, wide-area-sensitivity can reflect the character of power oscillation more clearly. The local sensitivity trajectories of load parameters are obvious only a short time after the disturbance and they are close to zero after about two seconds and can't describe the oscillation character of a power system more clearly. The simulation results proved the feasibility and validity of the wide area load modeling method. It is expected that the method will be used widely in a large scale power system in the future.
Investigation of Radiated Emissions in Power Line Communications Networks
Authors: Wang Lin Biao , So Ping Lam , See Kye Yak , Oswal Manish , Pang Teng Seng
Published: July 2008

Experimental studies are carried out to investigate the effectiveness of solving the electromagnetic interference (EMI) problem in power line communication (PLC) networks. A test bed is designed to study the effectiveness of the method. Measurements are carried out in a semi-anechoic chamber using a clamp-on current probe, a rod antenna and a loop antenna to compare the conducted and radiated emissions for the various cases. It is well known that the dominant mode of radiation is common mode (CM). The experimental results show that both the conducted and radiated emissions can be reduced by 15dB. This is achieved by increasing the impedance between the noise source and the power line network across the alternative noise path.
Analysis of Dough Sheeting and Heat Transfer during Baking of Unleavened Flat Bread (Chapathi)
Authors: Venkatesh Murthy K , Raghavarao KSMS
Published: July 2008

Retracted: The following article from International Journal of Food Engineering, “Analysis of dough sheeting and heat transfer during baking of unleavened flat bread (Chapati)" by K Venkatesh Murthy and KSMS Raghavarao originally published online April 2008 has been retracted.
Provitamin A Carotenoïd Content of Dried Fermented Cassava Flour: The Effect of Palm Oil Addition During Processing
Authors: Gouado Inocent , Demasse Mawamba Adelaide , Meyimgo Ouambo Ruphine Solange , Some Issa Touridomon , Félicité Tchouanguep Mbiapo
Published: July 2008

Vitamin A deficiency is a public health problem in developing countries. Cassava is a major staple food for most Africans. Most often, it is processed into dried fermented cassava (commonly called gari) to limit post harvest losses. The white or yellow type of gari can be obtained without or with the addition of red palm oil respectively. However in most African countries, the process is still traditional and the quantity of red palm oil varies from one producer to another. This study aimed to standardize the processing of cassava into gari and determine the carotenoïd content of dried fermented cassava roots cooked with different quantities of red palm oil. Grated samples from 210g of cassava tubers were fermented and fried at 120°C ± 5 for 10 minutes with (yellow gari) and without whole red palm oil (white gari). The quantities of red palm oil used were 2, 3, 4, 5 and 8 ml. The alpha and beta carotene contents of gari (experimental samples) and of yellow gari bought from a local market (commercial samples) were evaluated by HPLC. The organoleptic properties of the gari were assessed using 18 volunteers aged between 20 to 30 years accustomed to gari. From the results, the provitamin A carotenoïd content of gari obtained increased significantly (P< 0.05) with the quantity of oil used and were higher than that of the commercial samples. The alpha carotene ranged from 352.6 ± 5.5 µg/g to 1572.5 ± 15.9 µg/g (for 2 and 8 ml of palm oil respectively) and the beta carotene from 309.7 ± 24.8 µg/g to 1624.3 ± 45.8 µg/g (for 2 and 8 ml of oil respectively). These results suggest that the addition of red palm oil (4 ml/210 g of cassava) during the processing of cassava into yellow gari resulted in good retention of carotenoïd. Gari is a dry product, thus if it is well conserved after processing in dark airtight packages, it could be used as a good tool to reduce vitamin A deficiency.
Effects of Pretreatments on Drying Characteristics of Button Mushroom
Authors: Singh Upendra , Jain Sanjay Kumar , Doshi Anila , Jain Hemant Kumar , Chahar Vijay Kumar
Published: July 2008

The 0.5, 0.7 and 0.9 cm thick slices of button mushrooms were pretreated with different preservatives such as 0.5 per cent citric acid, 0.5 per cent KMS and 0.75 per cent EDTA for 10 minutes. Pretreated slices were dehydrated in a tray dryer at 40, 45, 50 and 55 °C and their drying characteristics such as rate of drying, diffusion rate and re-hydration ratio were studied. The qualities of dehydrated slices were evaluated on the basis of veil opening and amino acid content. The samples dehydrated at 50 °C showed better quality. The moisture diffusivity during tray drying varied from 1.05 x 10-8 to 7.48 x 10-09 m2/s and increased with drying air temperature.
Application of Ceramic Membrane Filtration to Remove the Solid in Nisin Fermentation Broth
Authors: Wu Zhaoliang , Ji Yuqiang , Guo Yanan , Hu Junna
Published: July 2008

Solid-liquid separation is an important step for the separation of nisin from the fermentation broth. This paper studied the application of ceramic membrane filtration to remove the solid. Experimental results indicated that the solid removal ratio was above 99% at pH 2.5, 40-50 °C, 0.1 Mpa, recovery of nisin being 84.4%, and while at pH 2.5 HCl was added to dilute the residue in the later stage. Compared to the recovery without the diluted residue, the yield increased 17.4%.
Modeling Drying Kinetics of Mustard in Fluidized Bed
Authors: Srinivasakannan Chandrasekar
Published: July 2008

Mustard (Brassica juncea), one of the popular oil seeds, is investigated for drying in Batch fluidized beds. Experiments were conducted to assess the kinetics of drying for the variation in the inlet air temperature, the inlet air flow rate and the solids holdup in the fluidized bed. The drying rate was found to increase significantly with increase in temperature and with flow rate of the heating medium, while decrease with increase in solids holdup. The duration of constant rate period was found to be insignificant, considering the total duration of drying. The drying rate was compared with various exponential time decay models and the model parameters were evaluated. The page model was found to match the experimental data very closely with the maximum root mean square error (RMSE) of less the 2.0%. The experimental data were also modeled using Fick's diffusion equation and the effective diffusivity coefficients was found to be within 1.69*10-11 to 3.26*10-11m2/s for the range of experimental data covered in the present study with RMSE less than 4%.
Different Strategies of Far-Infrared Radiation Application in Paddy Drying
Authors: Meeso Naret , Nathakaranakule Adisak , Madhiyanon Thanid , Soponronnarit Somchart
Published: July 2008

The applied strategy of far-infrared radiation in paddy drying is divided into two main processes with some overlapping, namely, series and combined drying processes. The first comprises fluidized-bed drying, far-infrared radiation, tempering and ambient air ventilation as well as transport of paddy, and the latter is the combination of far-infrared radiation and hot-air convection in fluidization technique. The changes of average moisture content, grain temperature and milling quality in each paddy drying process are presented together with mathematical models. The experiments showed that series drying process was more effective to apply in the aspects of paddy drying and milling qualities than combined drying process. Due to less effectiveness in combined drying process, heat and mass transfer models, only series drying process were developed. The simulation results indicated that the models were capable of satisfactorily predicting the simultaneous average moisture contents and grain temperatures of a paddy grain as compared with the experimental results.
Mathematical Models for Prediction of Rheological Parameters of Pineapple Juice
Authors: Dak Manish , Verma Radha Charan , Jain Manoj Kumar
Published: July 2008

Rheological characteristics of pineapple juice have been investigated and rheological parameters were evaluated using rotational viscometer at temperatures 20, 30 and 40*C at concentration 26.77, 18.99 and 14 % total solids. The experimental results followed the power law model for the best fit and the values of flow behaviour index (n) was less than unity (0.08 to 0.87) at all temperatures and concentrations indicating the shear thinning (pseudoplasticity) nature of juice. An obvious correlation between consistency coefficient in the range of 0.1 - 37.16 Pa.sn and inverse absolute temperature has been exhibited by Arrhenius model. The Power equation indicated that the consistency coefficient increased non-linearly with an increase in concentration. Mathematical models were developed for prediction of the consistency coefficient as a function of temperature and concentration. A good agreement was observed between experimental and theoretical values of the consistency coefficient predicted by models. The magnitude of activation energy was found to be in the range of 3.67 to 4.62 kJ/mol.K.
Inhibition of Food-Borne Pathogens by T1, a Novel Antimicrobial Peptide as a Potential Food Preservative
Authors: Tang Yali , Shi Yonghui , Zhao Wei , Hao Gang , Le Guowei
Published: July 2008

An efficient and convenient purifying procedure for recombinant peptide was established. Thereby, the aimed antimicrobial peptide T1 containing the conservative sequences derived from cecropin was successfully expressed and purified. The composition of amino acid of the purified peptide T1 was consistent with that of theoretical design. The significant antimicrobial activity of T1 against gram-positive and gram-negative bacteria was demonstrated, suggesting that the conservative sequences in cecropin play an important role in the antimicrobial mechanism and that antimicrobial peptide T1 has the potential to be used as the food preservative.
Rheological Properties of Diluted Pummelo Juice as Affected by Three Different Concentrations
Authors: Chuah Teong Guan , Keshani Samaneh , Chin Nyuk L , Lau Mun Chien , Chin Daniel S.J.
Published: July 2008

Pummelo is a popular fruit that has great potential to be commercialized. The physico-chemical characterization of pummelo juice such as proximate analysis, pH, moisture content, protein, fat, carbohydrate, ash and fibre contents are investigated. The rheological characterization of pummelo juice was modeled by several models, such as Bingham, Power Law and Casson models. Regression analysis shows good agreements for all three models applied in this study. Pummelo juice exhibits pseudoplastic behaviour under the conditions tested, as indicated by flow behaviour indices (n) ranging from 0.1 to 0.9 from power law model, indicating strong shear-thinning behaviour.
Shelf Life and Moisture Transfer Predictions in a Composite Food Product: Impact of Preservation Techniques
Authors: Roca Elisabeth , Adeline Dorothée , Guillard Valérie , Guilbert Stéphane , Gontard Nathalie
Published: July 2008

Three techniques to prevent moisture transfer in a multidomain food system constituted by a cookie in contact with a moist filling were investigated: reducing the water activity difference between components, reducing the effective moisture diffusivity of the cereal-based component, and applying an edible moisture barrier at the interface between components. Shelf-life of the food product was extended by 6 days by decreasing the water activity of the moist filling in contact from 0.99 to 0.64 (cookie aw being 0.23, 20°C). Decreasing effective moisture diffusivity from 1.56 to 0.99*10-11 m²/s by the addition of 2.35 g of fat in the formulation of the cookie was limited by technological and organoleptic considerations and allowed an extension of shelf-life of 2 more days. From a technical and nutritional point of view, the application of a sprayed edible barrier at the surface of the cookie was the more effective solution increasing shelf life of almost 8 days for only 1.7 g of fat per cookie.
Combined High Pressure and Subzero Temperature Phase Transition on the Inactivation of Escherichia coli ATCC 10536
Authors: Park Sung Hee , Hong Geun Pyo , Min Sang Gi , Choi Mi Jung
Published: July 2008

Combined high pressure and subzero temperature phase transition was performed to inactivate Escherichia coli ATCC 10536 at 200 MPa. Inactivation was compared among atmospheric pressure inactivation (APFI), pressure assisted freezing inactivation (PAFI), pressure assisted thawing inactivation (PATI), and pressure shift freezing inactivation (PSFI). Phase transition characteristics of microbial suspension were concurrently analyzed to investigate its influence on microbial inactivation. Phase transition temperature of E. coli ATCC 10536 suspension decreased to -23.8°C at 200 MPa, which is observed from the phase transition plateau. Supercooling was observed from nucleation temperature (-25°C) of PAFI. PATI resulted in the most inactivation of 4.37 log reduction, followed by PAFI and PSFI in decreasing order. APFI showed no efficacy of inactivation for E. coli ATCC 10536. Synergistic effect of high pressure, subzero temperature, and phase transition was expected for microbial inactivation.
Ohmic Heating Behavior of Certain Selected Liquid Food Materials
Authors: Kong Yin-qiu , Li Dong , Wang Li-jun , Bhandari Bhesh , Chen Xiao Dong , Mao Zhi-huai
Published: July 2008

Ohmic heating is an alternative fast heating technique for food products, which takes its name from Ohm's law. The basic principle of ohmic heating is the conversion of electrical energy into heat, resulting in internal energy generation. In this study, an experimental ohmic heating unit was designed and fabricated. Four kinds of liquid food materials (tap water, fruit-vegetable juice, yogurt and 0.5% aqueous sodium chloride solution) were heated on this laboratory scale static ohmic heater to evaluate the device's performance. Different voltage gradients (7.5V/cm, 11.25V/cm, 15V/cm, 18.75V/cm, 22.5V/cm and 26.25V/cm) were applied to study the heating behavior of liquid food materials. Results indicated that the voltage gradient significantly influenced the ohmic heating rates for all four materials tested. The electrical conductivity also changed significantly with temperature.
Composition Analysis of Litchi Juice and Litchi Wine
Authors: Zeng Xin An , Chen Xiao Dong , Qin Frank G.F. , Zhang Lu
Published: July 2008

In this study the total components of the litchi juice and litchi wine in the brewing process were analyzed with both a low temperature (13-16 °C) and a long time (8-10 days) for fermentation. 161.4 g/l total sugar, 2.2 g/l total acids and a high content of Vitamin C (354.12 mg/l) and K (1251.8 mg/l) were found in litchi juice and highly dried extract (25.6 g/l), low volatile acid (0.36 g/l) and low higher alcohols (0.048 g/l) were identified in the young litchi wine. The total free amino acid content in litchi wine (784.1 mg/l) was similar to that of grape wine (700-1300 mg/l). However the content of each single kind of amino acid in litchi wine was all at an average level (less than 50 mg/l). In total, 33 kinds of aroma compounds were identified in litchi wine by liquid-liquid extraction and GC/MS analysis, including 16 esters, 5 alcohols, 4 acids, 2 ketones, 1 phenol and 4 other chemicals. Ethyl octanoate (34.82%), ethyl decylate (15.41%), acetic ester (11.36%), ethyl hexoate (7.14%), acetic isopentyl ester (4.72%) and citronel ethyl acetate (1.94%) were the main constituents, which covered 75.39% and 93.03% of the total compounds and ester compounds, respectively. Content of higher alcohols was only 7.85%. A very interesting phenomenon was found in that no matter how much sulfurous acid was added and how much total SO2 content was observed in litchi juice or wine, the measured free state SO2 content was always below 10 ppm, which was quite different from that of grape wine.
Modeling of Oil Palm Fruit Maturity for the Development of an Outdoor Vision System
Authors: Razali Muhammad Hudzari , Wan Ismail Wan Ishak , Ramli Abd. Rahman , Sulaiman Md. Nasir
Published: July 2008

Color is the most important indicator farmers use to determine the maturity of the oil palm fruit called fresh fruit bunches (FFB) in the manual harvesting process. To automate the harvesting operation, the development of a vision system will replace the human eye for mature FFB recognition. In real plantation environments, variations in the daylight caused the light intensity to change, thus becoming the main issue that affects the automatic recognition process. In this study, the matured FFB was captured using a Sony digital Handycam on the day shift period. At the same time period of daylight intensity, a unit on foot candles (FC) also was simultaneously recorded using an Extech lightmeter data logger. From the linear regression analysis process, the mathematical model shows that there is a linear change between daylight intensity with the pixel value of the components green and blue. For the pixel value of the red component, the value will be linear at a maximum of 255 and at a certain intensity. To validate the mathematical model, this equation is used in the development of software for outdoor recognition processes.
Optimization of Supercritical Carbon Dioxide Extraction of Flaxseed Oil Using Response Surface Methodology
Authors: Jiao Shun-shan , Li Dong , Huang Zhi-gang , Zhang Zhen-shan , Bhandari Bhesh , Chen Xiao Dong , Mao Zhi-huai
Published: July 2008

The optimal conditions for the supercritical carbon dioxide (SC-CO2) extraction of flaxseed oil from flaxseed were determined using response surface methodology (RSM). A second-order regression for rotation-orthogonal composite design was used to study the effects of three independent variables: extraction pressure (MPa), extraction temperature (oC) and CO2 flow rate (L/h) on the yield of flaxseed oil. The independent variables were coded at five levels and their actual values selected on the basis of preliminary experiments. The results indicated that the yield of flaxseed oil was beyond 29% at a probability of 95% in the range of extraction pressure: 38.6-42.3 MPa, extraction temperature: 52.3-57.0 oC, and CO2 flow rate: 27.8-31.2 L/h. The optimal extraction conditions were extraction pressure of 41 MPa, extraction temperature of 56 oC and CO2 flow rate of 31 L/h according to the analysis of response surface. In this condition, the experimental yield of flaxseed oil was 29.96%, which was close to the predicted value of 30.52%.
The Effect of Refrigerated Storage on the Rheological Properties of Three Commercial Mozzarella Cheeses
Authors: Muliawan Edward B , Hatzikiriakos Savvas G
Published: July 2008

The linear and non-linear viscoelastic properties and the effect of refrigerated storage on the rheological properties of three commercial mozzarella cheeses was studied. The linearity of the rheological behavior of mozzarella cheese increases with temperature because of the ability for the cheese to flow easier at higher temperatures as well as the lack of yield stress at elevated temperatures. The generalized Maxwell model parameters obtained from the linear viscoelastic data were found to describe the linear relaxation dynamics of the mozzarella cheese satisfactorily. It is also shown that the damping function of mozzarella cheese, which is a measure of the degree of non-linearity, can be described by a generalized Zapas model. Although, the different commercial mozzarella cheeses do not exhibit linear viscoelastic differences at room temperature, they do show significant differences at 60°C. The effect of refrigerated storage on the linear viscoelastic properties is brand-dependent and indicates structural differences among cheese samples. Finally it is shown that the dynamic moduli decrease with longer refrigerated storage due to proteolysis activities and/or weakening of the casein matrix.
A Comparative Study of Sensitivity of Acetylcholinesterase in Detection of Organophosphorus Pesticide Residues
Authors: Xia Sun , Wang Xiangyou , Wang Xiao yu , Liu Zhe
Published: July 2008

In this paper, four enzymes from different sources used for pesticide detection were tested and compared: homogenate from chicken liver, chicken brain and cyprinoids brain were made respectively in the laboratory and Acetylcholinesterase (AChE) was purchased from Musca domestica. The inhibition of AChE activity under different concentrations of omethoate, trichlorfon and dichlorvos were compared. The results showed that the AChE activity in chicken liver and cyprinoids brain were very low. The capacities of activity inhibition of other two kinds of AChE were better. Chicken brain-esterase's inhibition rate achieved 24.16%, 50.56%, and 54.1% for 100ug/L of omethoate, trichlorfon and dichlorvos respectively. Chicken brain-esterase has high specific activity, is low cost, and easy to prepare, and the inhibition of the sensitivity to three organophosphorus pesticides is significantly higher than enzymes from chicken liver and cyprinoids brain. So the chicken brain-esterase could be a good choice to use to detect pesticide residues in agricultural products.
The Combined Effects of Heat Transfer Coefficient and Thermal Diffusivity on Heating Rates of Solid Materials - A Simple Analysis
Authors: Chen Xiao Dong , Zhang Lu , Li Dong
Published: July 2008

It is often perceived that an object with a higher thermal diffusivity will heat faster in comparison to that with a lower thermal diffusivity. This is however not always the case, as previously numerically proved by Palazoglu (2006). In this short communication, an analytical explanation of this is provided. Three generic cases are discussed which reinforce the observations made by Palazoglu (2006).
Droplet-Particle Agglomeration of Maltodextrin and Salt in a Small-Scale Spray Dryer
Authors: Langrish Tim , Ali D. , Asplet M.
Published: July 2008

The technique of in-chamber blending in practice has been investigated, by altering the configuration of a Buchi B290 small-scale spray dryer having a two-fluid nozzle, through adding an extra pipe into the chamber to agglomerate maltodextrin (DE18) particles with 20% salt solution sprayed through the atomizer. Scanning Electron Micrographs showed the importance of splash impacts between salt droplets and maltodextrin particles in this geometry, suggesting that the collision efficiency is strongly affected by whether or not the salt droplets completely surround the dry maltodextrin particles. Changing the air inlet temperature did not affect the measured amount of collisions (from Atomic Absorption Spectroscopy) significantly, but both the main air and the nozzle air flow rates had significant effects on the collision outcomes.
The Effects of Cryoprotectants on the Survival Rate of Saccharomyces cerevisiae in a Freeze-Dried Gelatin Matrix
Authors: Choi Mi-Jung , Min Sang-Gi , Hong Geun Pyo
Published: July 2008

This study was carried out to determine the effects of cryoprotectants on yeast survival rate. Here, yeast was mixed with the following cryoprotectants: saccharose, hydroxyethylstarch, trehalose, lactose, caboxymethyl cellulose, and ?-carrageenan, and then frozen at -40°C, -30°C, and -18°C, respectively. The freeze-dried gelatin matrices were cut horizontally into 5 mm thick slices from the bottom and their pore sizes were measured. The freezing temperature (-40°C, -30°C, and -18°C) affected the freezing rate, and the partial freezing rate in the matrix was dependent on the distance. The higher the sample distance was from the bottom, the lower the partial freezing rate. We also found that the cryoprotectant concentration affected the freezing rate. Furthermore, the cryoprotectant and freezing rate affected the different survival rates of the yeast. The highest survival rate occurred with saccharose and trehalose, and was obtained by freezing at -40°C, which depended significantly on the concentration of trehalose. The ice dendrite sizes that formed during freezing at -40°C, -30°C, and -18°C showed a direct relationship with the freezing rate and cryoprotectant concentration. In the samples, the maximum primary ice dendrite size was 215.9 ?m at 1%, and the minimum primary ice dendrite size was 145.6 ?m at 5%, from the experiments at -18°C.
Optimization of Osmotic Dehydration of Toona Sinensis Leaves Using Response Surface Methodology
Authors: Wang Changlu , Li Lu , Li Zhanyong , Liu Changjin , Chen Mianhua
Published: July 2008

Toona Sinensis leaves were dehydrated by osmosis. The effects of temperature, immersion time, sucrose and salt concentration on water loss and solid gain during osmotic dehydration were investigated by response surface methodology. Consequently, second order polynomial models were developed for water loss and solid gain as a function of the experimental parameters. By applying Excels Solver feature, an optimal solution for maximum water loss and minimum solid gain was given at temperature of 30oC, sucrose concentration of 50%, salt concentration of 10%, and immersion time of 4 hours.
Effect of Process Parameters on Quality Properties of Microwave Dried Red Pitaya (Hylocereus costaricensis)
Authors: Mad Nordin Mariam Firdhaus , Wan Daud Wan Ramli , Meor Talib Meor Zainal , Hassan Osman
Published: July 2008

The effect of microwave power density on the microwave drying of red pitaya (Hylocereus costaricensis) was investigated using a small modified commercial microwave. Microwave power density was varied in the range of 5.47 to 19.02 W/g. The ambient, internal sample and sample surface temperatures, and moisture loss were measured during microwave drying at various microwave power densities. The drying rate increased with increasing power density. The temperature profiles rapidly reached their saturation level. The experimental moisture loss data were fitted to the Tang and Cenkowski drying model using a value of residual sum of squares (RSS) to evaluate the goodness of fitting the model. The dried product was analysed to examine the quality such as color, shrinkage, tensile hardness and structure. The results showed that the color change is higher at higher power density and temperature because of the faster browning rate and faster drying rate. The beginning of the color change corresponded closely to the beginning of the falling rate period. The microwave drying also caused the red pitaya to shrink to a greater extent of up to 70% at higher power density because of the faster drying rate. The internal structure also tended to collapse during microwave drying.
Public Support for National Health Insurance: The Roles of Attitudes and Beliefs
Authors: Bundorf M. Kate , Fuchs Victor R.
Published: July 2008

The U.S. is the only developed country without some form of national health insurance. Yet, public opinion polls have consistently reported solid majorities in favor of such a system. In this paper, we examine whether attitudes toward different roles of government and beliefs that may be related to those attitudes are consistent with widespread support for national health insurance. Our analysis is based on the premise that a system of national health insurance would require government redistribution and government intervention in health care markets. We find that people who have favorable attitudes toward government economic intervention are 27 percentage points more likely and those with favorable attitudes toward government economic intervention are 18 percentage points more likely to favor national health insurance than those with unfavorable attitudes. The most intense support for national health insurance, strongly favoring as opposed favoring it, is among people with favorable attitudes toward both roles of government. Consistent with research from other social programs, we find that the beliefs regarding racial minorities, as well as beliefs regarding individual control over life, limit support for national health insurance in the U.S. On the other hand, negative beliefs regarding businesses are an important source of support for national health insurance. We conclude that significant changes in either attitudes and beliefs or their relationship with support for national health insurance are probably necessary to create a strong majority in support of such legislation.
Does General Motor Imagery Ability (via Questionnaire) Predict Estimation of Reachability in Children?
Authors: Gabbard Carl P , Cacola Priscila , Cordova Alberto
Published: July 2008

With the present study we addressed the question of whether general motor imagery ability (MIA), as determined by questionnaire, predicts estimation of reachability in children ages 6 to 12 years of age. Estimation of reachability involves the use of motor (kinesthetic) imagery to derive a perceptual/cognitive (verbal) estimate of whether an object is within or out of reach. Our initial prediction was that older children would score higher than their younger counterparts in MIA, resulting in more accurate reach responses. Results indicated that, although younger children's MIA scores were significantly lower than their older counterparts, reach responses were similar. Moreover, relationship analysis indicated a non-significant association between MIA and estimation of reachability. Explanations for the MIA difference focus on differences in cognitive ability and movement experience. Furthermore, we speculated that with the visual information provided by the reach task, the younger children were able to imagine reachability at a level comparable to their older counterparts. In essence, the results suggest that the MIA questionnaire and estimation of reach task tap different processing modes, which account for the differential outcome.
Process Simulation for Pulp and Paper Industries: Current Practice and Future Trend
Authors: Dahlquist Erik
Published: July 2008

In this paper the historical perspective of the use of simulation in pulp and paper industry is presented and different applications discussed. Scientific papers as well as research and development work made by suppliers and software vendors is covered. The review covers a number of applications. First data reconciliation, root cause analysis and decision support is covered. This forms the basis for more advanced optimization and control. Physical models are then covered as they are especially good for engineering and design of new processes or the rebuilding of existing processes. As a complement for on-line applications quality property predictions with soft sensors like MVDA, ANN and grey box models are covered. When the process signals have been checked and soft sensors developed it is possible to perform process optimization and model based control and also to develop expert systems for decision support. Simulators also are used for operator training to increase the understanding of the processes as well as the interaction with the DCS system. Finally the future of process simulation in pulp and paper industry is discussed.
Numerical Solution of Non-Linear Algebraic Equations by Modified Genetic Algorithm
Authors: Danish Mohammad , Kumar Shashi , Kumar Surendra
Published: July 2008

Numerous unit operations in chemical and process engineering can be represented as a system of non-linear algebraic equations, when modeled for steady state operation ,e.g. isothermal and non-isothermal operations of a series of CSTRs, batteries of evaporators, networks of various separation operations (flash drum, mixers), distillation, extraction and absorption columns, and pumps and piping networks etc. These governing equations are sometimes very difficult to solve due to the nonlinear and uneven nature associated with them. The difficulty level increases when the resulting set of equations become flat near their zeros and thus derivatives based schemes mostly diverge or give poor results. Many a times, even a good initial guess in conventional numerical techniques do not guarantee to have a true solution and problem specific methods have to be designed. This whole scenario can also be viewed as an optimization problem having equality constraints only and casting the equations in the form of norm of function vector, which formulates an objective function to be minimized. The true minimum thus found gives us the correct solution vector. Recently, Genetic Algorithms have been quite effectively used to solve many complex engineering optimization problems. In continuation of our earlier research work where an elitist genetic algorithm was developed for the solutions of various difficult MINLP problems (Danish et al. 2006a and b), this research work extends its application for the solution of difficult non-linear algebraic equations. A novel scheme of dynamic mutation parameter as a function of fitness along with dynamic penalty has been proposed. The small value of mutation parameter in initial stages enables the algorithm to search globally, and the solution thus found is refined by keeping its value higher in later generations. This new scheme is found to be very effective in the sense that the algorithm requires very small population size and comparatively lesser number of generations to give reasonably good solutions. To test the efficacy of algorithm we have solved five sets of difficult non-linear algebraic equations (Dennis and Schnabel, 1983). It is worthwhile to mention that one of these equations was having both its Jacobian and Hessian as zero, at its true solution. Applicability of the developed GA was also demonstrated by simulating an industrial case study of triple effect evaporator used for concentrating the caustic soda solution (Zain and Kumar, 1996), which also poses difficulty during numerical simulation by Newton-Raphson method.
Comparative Control Study of a High-Purity Ternary Batch Distillation
Authors: Adari P. V. Radha Krishna , Jana Amiya K
Published: July 2008

This paper presents a comparative closed-loop performance study on a multicomponent batch distillation column that produces high-purity distillate product. Initially, the distillation model representing a ternary system of cyclohexane-toluene-chlorobenzene has been simulated to observe the open-loop dynamics at the start-up as well as production phase. The next three control schemes, namely classical proportional integral (PI) controller, nonlinear proportional integral (NLPI) control strategy and gain-scheduled proportional integral (GSPI) law, have been designed and applied on the simulated distillation column. Numerical experiments based on servo and regulatory tests show that the GSPI algorithm provides relatively better results than the other two PIs.
Reliability of Convective Diffusion Process in Stenosis Blood Vessels
Authors: Saket R.K. , Kumar Anil
Published: July 2008

This paper presents a convective dominated reliable diffusion process in an axi-symmetric tube with a local constriction simulating a stenos artery considering the porosity effects. The investigations demonstrate the effects of wall shear stress and recirculation flow on the concentration distribution in the vessels lumen and on wall mass transfer keeping the porosity in view. The flow is governed by the incompressible Navier-Stokes equations for Newtonian fluid in porous medium. The convection diffusion equation has been used for the mass transport. The effect of porosity is examined on the velocity field and wall stress. The numerical solutions of the flow equations and the coupled mass transport equations have been obtained using a finite difference method. This paper explains the reliable effects of flow porosity on the mass transport.
Simulation Model of the Thermodynamic Cycle of a Three-Cylinder Double-Acting Steam Engine
Authors: Thoendel Evzen
Published: July 2008

Today, steam engines are used for special purposes only, for example to reduce steam pressure in pressure reduction stations, where they replace the traditional and inefficient throttling process. Throttling is the most used way to control the pressure in steam reduction stations. This way is unsatisfactory from the economical point of view, because the exergy is lost uselessly. It is a part of heat energy that can perform a work. The better way of a pressure reduction is an expansion in a backpressure turbine or in a steam engine by simultaneous transformation of the heat energy into electricity (cogeneration). This article describes the design and implementation of the mathematical model of a steam engine used as pressure regulator in a pressure reduction station. The present model is a part of a comprehensive mathematical model of a cogeneration unit and also a part of the author's doctoral thesis. The model assumes detailed mathematical description of physical processes in a steam engine and implementation in an MATLAB-SIMULINK software environment.
Editorial: Special Issue Contributed by CITICOMS 2007 - International Conference on Modeling and Simulation, Selected Papers
Authors: Kumar Surendra
Published: July 2008

Coimbatore Institute of Technology, India, organized an International Conference on Modeling and Simulation (CITICOMS 2007) during August 2729, 2007. The conference covered research works on modeling & simulation in a large number of diverse disciplines viz., biotechnology, chemical engineering, mechanical engineering, civil engineering, mathematics and nanotechnology, electrical engineering, electronic engineering and computer engineering.This special issue presents a set of nine selected research papers, which have undergone the peer-review process of the journal of Chemical Product and Process Modeling. Although these papers do not cover the entire gamut of modeling and simulation activities, they certainly present interesting and useful topics. In particular these topics include the black box modeling approach for identification of nonlinear systems, kinetic modeling of the adsorptive removal of toxic and hazardous pollutants from wastewaters, analysis and modeling of homogeneous tubular reactors, monolithic catalytic converters, and a constitutive model equation for the rheological behaviour of three phase polymer blends or so called double emulsions.
Determinants of Business Tax Compliance
Authors: Nur-tegin Kanybek D
Published: July 2008

This paper provides empirical evaluation of a number of determinants of tax evasion by firms. The analysis includes both standard determinants, such as tax rates and probability of detection, and non-traditional factors, such as trust in government, compliance costs, and corruption. Firm-level survey data from 4,538 firms in 23 transition economies are analyzed. One of the main findings is that fighting corruption is more important in deterring tax evasion than conventional measures.