Open Access. Powered by Scholars. Published by Universities.®

Engineering Commons™

Open Access. Powered by Scholars. Published by Universities.®

Journal

Discipline
Institution
Keyword
Publication Year
Publication
File Type

Articles 23791 - 23820 of 27383

Full-Text Articles in Engineering

Identification Of Unbalanced Forces And Foundation Parameters Of Rotating Machines From Vibration Measurements, Nalitolela G Dec 2008

Identification Of Unbalanced Forces And Foundation Parameters Of Rotating Machines From Vibration Measurements, Nalitolela G

Tanzania Journal of Engineering and Technology (TJET)

A technique is described to use measured vibration data of a rotating machine and its foundation to identify unbalanced forces, stiffness and damping parameters of the mountings, and the parameters of the foundation. It is based on an idealisation treating the rotor, the machine structure and the foundation as rigid masses supported by springs and dampers. Operational vibration data of the machine and its foundation before and after the rotating unbalanced forces are perturbed by adding unbalanced mass to the rotor are used in the identification procedure. Once the parameters are identified, dynamic forces transmitted to the foundation can be …


Design And Development Of A Prototype For A Web-Based Interface For Online Material For Tanzanian Youth, Mjema A.M Dec 2008

Design And Development Of A Prototype For A Web-Based Interface For Online Material For Tanzanian Youth, Mjema A.M

Tanzania Journal of Engineering and Technology (TJET)

A prototype of a web-based interface for an online database was developed to be used by youth organizations in Dar-es-Salaam. A participatory approach involving secondary students in the identification of user interface requirements, in designing and testing the prototype was used. A questionnaire was designed and manned in seven secondary schools in Dar-es-Salaam to estimate the Internet usage. Interviews were conducted to countercheck the questionnaire responses. The interview and the questionnaire helped to come up with a set of user requirements for the web-based interface of an online information search. From the specifications of the user requirements the author was …


The Multivariate Statistical Analysis Of Abiotic Parameters Of The Lake Tanganyika Sub Catchment, Hudson Nkotagu Dec 2008

The Multivariate Statistical Analysis Of Abiotic Parameters Of The Lake Tanganyika Sub Catchment, Hudson Nkotagu

Tanzania Journal of Engineering and Technology (TJET)

Results from multivariate statistical analysis of abiotic parameters conducted during the dry season at 20 accessible sites on 8 rivers, 2 lakes and a dam covering the Lake Tanganyika sub catchment are discussed. Standard methods were used to determine the levels of abiotic parameters from water samples. Physical parameters including DO, EC, Eh, turbidity, temperature, pH and secchi transparency were measured in situ while chlorophyll a was determined in the laboratory. Nutrients such as NO3-, SiO2, PO4 3- and Fe2+ were determined along with HCO3-. Factor analysis resulted in four factors including increased primary productivity, redox conditions, dissolution, and reduction …


An Equation For Estimating The (R) Usle Slope Steepness Factors, Mathew Mulemgera Dec 2008

An Equation For Estimating The (R) Usle Slope Steepness Factors, Mathew Mulemgera

Tanzania Journal of Engineering and Technology (TJET)

Abstract Currently three equations are used for calculating slope steepness factor for the Revised Universal Soil Loss Equation (RUSLE); one for slopes less than nine percent, the second for slopes equal or greater than nine percent, and the third equation that has been proposed for use in China for slopes equal or greater than 17 %. The three equations have linear relationships between slope steepness factor, S and the sine of the slope angle, θ. The three equations under predict the factor, S when used on slope steepness beyond the data sets used to develop them. In addressing this problem …


The Systemic Nature Of Action Learning Programmes, G Mwaluko Dec 2008

The Systemic Nature Of Action Learning Programmes, G Mwaluko

Tanzania Journal of Engineering and Technology (TJET)

A lot of attention has been paid on action learning in the last four decades or so and the success of such programmes has also been widely publicized. But why have these programmes been so effective in helping organizations cope with change? Many authors state that the success of such programmes is due to the fact that they link learning to actions. Yet others claim that action learning programmes succeed because they involve employee empowerment and provide a much greater learning curve. In this paper the authors hold that action learning programmes succeed because they are partly systemic and can …


Analytical Modeling Of A Large Local Area Network - Part I: Internet Traffic Characterization, Mathew Luhanga Dec 2008

Analytical Modeling Of A Large Local Area Network - Part I: Internet Traffic Characterization, Mathew Luhanga

Tanzania Journal of Engineering and Technology (TJET)

The goal of both IP network operators and the end users is to get the highest performance from the system for a given cost. This makes Performance a key criterion in the design, procurement, and use of computer and communication systems. In order to address problems associated with performance degradation of operational communications systems, over the last decade, traffic engineering techniques have emerged in an attempt to optimize communication systems’ performance and ensure more efficient use of their resources. One of these techniques is analytical modeling. Analytic performance models are an excellent tool for quickly evaluating the performance of operational …


Study On Mechanical Properties Of A356 Alloys Enhanced With Preformed Thixotropic Structure, Shueiwan H. Juang, Shyh-Ming Wu Dec 2008

Study On Mechanical Properties Of A356 Alloys Enhanced With Preformed Thixotropic Structure, Shueiwan H. Juang, Shyh-Ming Wu

Journal of Marine Science and Technology–Taiwan

A preformed A356 alloys with thixotropic structure (designated SSM-A356) was systematically studied on mechanical properties in order to establish the database for further investigations in forming and heat treatment. Because of the specific microstructure and characteristics, the heat treatment conditions of SSM-A356 were explored through the observations of microstructure and the measurement of micro-hardness. In the investigation of heat treatment, it was observed that the eutectic silicon was refined and spheroidized which is unlikely for conventional processing. The mechanical testing results showed that the yield and ultimate tensile strength of SSM-A356 were respectively around 115% and 34% greater than those …


Assessment Of Ground Shaking In Ilan County, Taiwan, Hui-Mi Hsu, Sao-Jeng Chao, Howard Hwang Dec 2008

Assessment Of Ground Shaking In Ilan County, Taiwan, Hui-Mi Hsu, Sao-Jeng Chao, Howard Hwang

Journal of Marine Science and Technology–Taiwan

This paper presents an estimation of ground shaking intensity in the Ilan area caused by two scenario earthquakes. On the basis of seismic activity in the study area, the seismic zones, including Okinawa trough seismic zone section A and Suao-Hualien offshore seismic zone are established. The earthquakes occurring in these two zones are considered as the scenario earthquakes. The hundreds of boring logs are also collected and classified into three site classes as specified in the Taiwan Seismic Building Code. The intensity of ground shaking in the Ilan area caused by a scenario earthquake is then estimated by using an …


Impact Of Fire-Through And Misfire In Rectifier Valves On A Turbine Generator Neighboring To A Hvdc Inverter Station, Ming-Te Liang Dec 2008

Impact Of Fire-Through And Misfire In Rectifier Valves On A Turbine Generator Neighboring To A Hvdc Inverter Station, Ming-Te Liang

Journal of Marine Science and Technology–Taiwan

The major purpose of this paper is the theoretical elucidation of the corrosion tube growth mechanism of mild steel occurred from the effect of pH value and oxygen corrosion at elevated pressure provided by Riggs et al. [6]. Based on the Nernst-Planck equation, continuity principle, Green's theorem, Stokes's theorem and the equation of Newton's second law of motion, the mechanism of corrosion tube development can be explained theoretically. The Bernoulli sum is contant at any cross-section of tubular corrosion product. The implication of the present results are theoretically enhanced the formation of corrosion tube mechanism.


The Study Of Price Accept Threshold For The ??Lue Highway??Tour Of The North-East Region In Taiwan, Hung-Yen Chou, Jin-Long Lu, Chiang Fu Dec 2008

The Study Of Price Accept Threshold For The ??Lue Highway??Tour Of The North-East Region In Taiwan, Hung-Yen Chou, Jin-Long Lu, Chiang Fu

Journal of Marine Science and Technology–Taiwan

The “Blue Highway” in the NE region of Taiwan includes the tour itineraries of Keelung-Suao, Suao-Hualien and Keelung-Hualien, each with its individual oceanic scenic features and its potential corresponding onshore scenic spots. This study explores the relationship between the “Blue Highway” tour portfolios and price attributes to collect the preference recognition of the public concerning the NE region “Blue Highway” tour itineraries and prices with the stated preference method. The utility function of the discrete choice model assumes the impact effect among attributes to be in a linear relationship plus percentages. The price threshold model improves the assumption of this …


Theoretical Elucidation On The Corrosion Tube Growth Mechanism Of Mild Steel In The Effect Of Ph On Oxygen Corrosion At Elevated Pressures, Ming-Te Liang Dec 2008

Theoretical Elucidation On The Corrosion Tube Growth Mechanism Of Mild Steel In The Effect Of Ph On Oxygen Corrosion At Elevated Pressures, Ming-Te Liang

Journal of Marine Science and Technology–Taiwan

The major purpose of this paper is the theoretical elucidation of the corrosion tube growth mechanism of mild steel occurred from the effect of pH value and oxygen corrosion at elevated pressure provided by Riggs et al. [6]. Based on the Nernst-Planck equation, continuity principle, Green's theorem, Stokes's theorem and the equation of Newton's second law of motion, the mechanism of corrosion tube development can be explained theoretically. The Bernoulli sum is contant at any cross-section of tubular corrosion product. The implication of the present results are theoretically enhanced the formation of corrosion tube mechanism.


Case Study Of Wind-Resistant Design And Analysis Of High Mast Structures Based On Different Wind Codes, Ching-Wen Chien, Jing-Jong Jang Dec 2008

Case Study Of Wind-Resistant Design And Analysis Of High Mast Structures Based On Different Wind Codes, Ching-Wen Chien, Jing-Jong Jang

Journal of Marine Science and Technology–Taiwan

The high mast structure (HMS) has the characters of light weight and high cost efficiency. Therefore, it is widely used in the modern construction industry. It has a large the ratio of height (H) to least horizontal dimension (D) that makes it a particularly more slender and wind-sensitive than any other structures. Therefore, the purpose of this research is to develop the wind-resistant design (WRD) procedure for the slender, tapered support structures of HMS subjected to wind-induced excitation from vortex shedding and gust buffeting. This paper illustrates the theoretical basis and the analytical development of the WRD; including calculating gust …


Variable-Thickness Boundary Layers For Sliding Mode Control, Chyun-Chau Fuh Dec 2008

Variable-Thickness Boundary Layers For Sliding Mode Control, Chyun-Chau Fuh

Journal of Marine Science and Technology–Taiwan

Sliding mode control is a nonlinear feedback control technique which provides good robustness against modeling uncertainties and external disturbances. However, as the uncertainties or disturbances increase, a greater control input is required, and the control signal may cause an undesirable chattering phenomenon. In general, the further the system trajectory from the origin, the more violent the chattering effect. However, as the trajectory moves closer to the origin, the degree of chattering gradually reduces. As a result, even if an attempt is made to eliminate chattering by introducing a small constant boundary layer around the sliding surface, the chattering phenomenon may …


Discrete-Time Output Feedback Sliding Mode Control For Uncertain Systems, Ming-Chang Pai Dec 2008

Discrete-Time Output Feedback Sliding Mode Control For Uncertain Systems, Ming-Chang Pai

Journal of Marine Science and Technology–Taiwan

This paper presents a discrete-time output feedback sliding mode control to stabilize a class of linear uncertain systems in which the state is unavailable and no estimated state is required. The proposed sliding mode controller is derived to guarantee the existence of quasi-sliding mode by using output feedback only and the stability of overall closed-loop system is assured. This scheme ensures the robustness against parametric uncertainties and disturbances. Neither chattering phenomenon will occur nor the knowledge of upper bound of uncertainties is required. Simulation results demonstrate the efficacy of the proposed control methodology.


The Manpower Supply Planning And Shift Setting For Mass Rapid Transit Carriage Maintenance In Short-Term Operations, Shangyao Yan, Chia-Hung Chen, Miawjane Chen Dec 2008

The Manpower Supply Planning And Shift Setting For Mass Rapid Transit Carriage Maintenance In Short-Term Operations, Shangyao Yan, Chia-Hung Chen, Miawjane Chen

Journal of Marine Science and Technology–Taiwan

An effective carriage maintenance plan cannot only reduce the mass rapid transit system operating costs, but is also directly related to its safety and schedule punctuality. Traditionally, the arrangement of the carriage maintenance manpower supply has been based on staff experience, and has been performed manually following simple rules. This is not only time-consuming but often ineffective. Therefore, in this research, we incorporate flexible management strategies, different combinations of principles, and the related operating constraints, to develop a basic carriage maintenance manpower supply plan model. Furthermore, we construct an integrated model by modifying the basic model, which can help an …


Preparation And Characterization Of Particles From Chitosan With Different Molecular Weights And Their Trimethyl Chitosan Derivatives For Nasal Immunization, W Boonyo, H E. Junginger, N Waranuch, A Polnok, T Pitaksuteepong Dec 2008

Preparation And Characterization Of Particles From Chitosan With Different Molecular Weights And Their Trimethyl Chitosan Derivatives For Nasal Immunization, W Boonyo, H E. Junginger, N Waranuch, A Polnok, T Pitaksuteepong

Journal of Metals, Materials and Minerals

According to previous studies, molecular weights (MW) of chitosan presented an influence on the level of immune response to model antigen when administering with chitosan through nasal route. Moreover, trimethyl chitosan (TMC) with a degree of quaternization (DQ) of 40%, chitosan derivatives, was also shown to be the most potent nasal OVA delivery platforms compared to TMC with DQ of 20% and 60% in mice model. The aims of this study were to prepare particles from chitosan with difference MW and their TMC derivatives (DQ = 40%) and to characterize size, zeta potential, loading efficiency and release profile in order …


Chitosan/Calcium Phosphate Composites Scaffolds Prepared By Membrane Diffusion Process, P Thanaphat, P Thunyakitpisal, W Techaboonyakiat Dec 2008

Chitosan/Calcium Phosphate Composites Scaffolds Prepared By Membrane Diffusion Process, P Thanaphat, P Thunyakitpisal, W Techaboonyakiat

Journal of Metals, Materials and Minerals

Hydroxyapatite (Ca10(PO4)6(OH)2, HAp) and Dicalcium phosphate dihydrate (CaHPO4.H2O, DCPD) were homogeneously hybridized into chitosan solution by membrane diffusion process. The threedimensional scaffolds were obtained by freeze-drying process. The organic and inorganic contents of scaffold were determined by using thermogravimetry analysis (TGA). The surface morphology of the scaffold and characteristic of calcium phosphate were investigated by scanning electron microscope (SEM), energy dispersive X-ray spectrometer (EDX), and X-ray diffraction (XRD), respectively. Compressive modulus was also determined by dynamic mechanical analysis (DMA). The hybridized inorganic content ranges from 35-45%. Both chitosan/HAp and chitosan/DCPD scaffolds showed interconnected porous structure. The calcium to phosphorus ratios …


Bs News Dec 2008

Bs News

Building Services Engineering

No abstract provided.


Preparation Of Ultrafine Silver Powder Using Glycerol As Reducing Agent, E Nisaratanaporn, K Wongsuwan Dec 2008

Preparation Of Ultrafine Silver Powder Using Glycerol As Reducing Agent, E Nisaratanaporn, K Wongsuwan

Journal of Metals, Materials and Minerals

The production of silver nanoparticles and sub-micron particles can be achieved by silver alkoxide from silver sulfate and subsequently reducing with glycerol. To reduce the particle size of silver sulfate precursors, ball milling was employed to reduce particle sizes down to 0.81 microns. However, silver sulfate without grinding provided smaller particle sizes of silver particles as opposed to ground specimens. Stirring silver alkoxide simultaneously was efficient to provide for uniform distribution of silver powder. The silver powder thus produced had brain-like shape consisted of very fine aggregate silver particles. The yield of silver powder was in the range of 95-99 …


Influence Of Reinforced Plastomers On Injection Moulds Wear, A Guzanová, J Brezinová Dec 2008

Influence Of Reinforced Plastomers On Injection Moulds Wear, A Guzanová, J Brezinová

Journal of Metals, Materials and Minerals

The contribution deals with wear of injection moulds based on aluminium alloy Alumec 89 in friction couples with plastomers reinforced with different glass fibres content. Friction relations in injection moulding were simulated by adhesion dry wear test with help of Amsler equipment with area contact of friction couple. Wear intensity was evaluated by friction coefficient and relative wear by weight loss. Simultaneously, changes of aluminium alloy surface morphology after wear in particular friction couples were analysed.


Demonstration Of The Ntc Ceramic Application For Temperature Measurement And Control Using The Labview-Based Measurement System, T Panmatarith, K Poatong Dec 2008

Demonstration Of The Ntc Ceramic Application For Temperature Measurement And Control Using The Labview-Based Measurement System, T Panmatarith, K Poatong

Journal of Metals, Materials and Minerals

In the present paper, ZnO+0.01SnO2 ceramics were prepared using a standard ceramic method. We present the NTC ceramic application for temperature measurement and control using the LabVIEW-based measurement system. The measured resistance of the sample at room temperature was about 6.5 kΩ. The electrical resistance versus temperature of the sample was measured. The negative temperature coefficient of resistance of the sample was -1.018 %/°C. This sample showed NTC effect and exhibited NTC resistor, indicating their potential application as temperature sensor with low cost. It can be used as temperature sensor by using the NTC effect . The measured temperature (T) …


Production Of Sponge Rubber For Monolayer Rubber Stamp Using Salt Leaching Method, W Trakanpruk, Y Rodthong Dec 2008

Production Of Sponge Rubber For Monolayer Rubber Stamp Using Salt Leaching Method, W Trakanpruk, Y Rodthong

Journal of Metals, Materials and Minerals

Sponge rubber used for monolayer rubber stamp was produced from nitrile butadiene rubber (NBR). Open cells in sponge rubber were created using salt leaching method. Effect of size and amount of sodium chloride which was used as a water soluble salt on the creation of open cells in the rubber was investigated. Carbon black was used as a filler. A different type of surfactant was added to increase the leaching out of salt from the rubber. Cure characteristics of the compound rubbers: maximum torque, minimum torque, scorch time and cure time as well as hardness of the prepared sponge rubber …


Application Of Chitosan In Rice Production, S Boonlertnirun, C Boonraung, R Suvanasara Dec 2008

Application Of Chitosan In Rice Production, S Boonlertnirun, C Boonraung, R Suvanasara

Journal of Metals, Materials and Minerals

Chitosan is a natural biopolymer which stimulates growth and increases yield of plants as well as induces the immune system of plants. The objectives of this study were to determine appropriate applications for increasing of the rice yield. The experiment was performed with randomized complete block design ( RCBD) with four replications. Four treatments were done as follows : no chitosan application, seed soaking with chitosan solution, seed soaking and soil application with chitosan solution and seed soaking and foliar spraying with chitosan solution. The results showed that application of chitosan by seed soaking and soil application four times throughout …


Preparation Of N-Acetyl-D-Glucosamine Using Enzyme From Aspergillus Sp., P Setthakaset, R Pichyangkura, A Ajavakom, M Sukwattanasinitt Dec 2008

Preparation Of N-Acetyl-D-Glucosamine Using Enzyme From Aspergillus Sp., P Setthakaset, R Pichyangkura, A Ajavakom, M Sukwattanasinitt

Journal of Metals, Materials and Minerals

N-acetyl-D-glucosamine (GlcNAc) is one of the basic constituents of mammal cartilage, which is known to help repair deteriorating cartilage and relieve pain and inflammation in osteoarthritis patients. The preparation of GlcNAc from squid pen β-chitin by using Aspergillus sp. chitinase in enzymatic hydrolysis is studied. The cultivation of the fungus in colloidal chitin minimum media at pH 3.5 and 40°C for 5 days gives the highest chitinolytic activity of 3.1 U/mL. The crude enzyme obtained from the the cultivation is used in the hydrolysis of milled squid pen β-chitin (50μm) at pH 4 (acetic acid 2M) and 45°C using 22 …


Factors Affecting Preparations Of Chitosan Microcapsules For Colonic Drug Delivery, K Huanbutta, M Luangtana-Anan, P Sriamornsak, S Limmatvapirat, S Puttipipatkhachorn, J Nunthanid Dec 2008

Factors Affecting Preparations Of Chitosan Microcapsules For Colonic Drug Delivery, K Huanbutta, M Luangtana-Anan, P Sriamornsak, S Limmatvapirat, S Puttipipatkhachorn, J Nunthanid

Journal of Metals, Materials and Minerals

This work aimed at studying factors affecting preparations of chitosan microcapsules for colonic drug delivery. Chitosan microcores (CS, 45kDa, 87% degree of deacetylation) containing diclofenac sodium (DS) coated with Eudragit®S100 (ED) were prepared by a desolvation technique. Sodium sulfate was used as a desolvating agent and the drying process was freeze-drying. Factors affecting morphology, particle size and zeta potential of microcapsules were evaluated, i.e. weight ratio of DS:CS:ED, surfactant (polysorbate 80), anti-adherent (silicon dioxide), and the use of sonication or homogenization in preparation processes. The weight ratio of DS:CS:ED at 1:2:6 provided the smallest microcapsules of about 82.37±1.61 micrometer in …


Fabrication Of Porous Bioactive Glass-Ceramics Via Decomposition Of Natural Fibres, P Sooksaen, S Suttiruengwong, K Oniem, K Ngamlamiad, J Atireklapwarodom Dec 2008

Fabrication Of Porous Bioactive Glass-Ceramics Via Decomposition Of Natural Fibres, P Sooksaen, S Suttiruengwong, K Oniem, K Ngamlamiad, J Atireklapwarodom

Journal of Metals, Materials and Minerals

Porous bio glass-ceramics were prepared via natural fibres burning-out process. Glass-ceramics were fabricated by controlled crystallization of suitable glass compositions to give required crystalline phase/s. Porous structure was formed alongside during burning-out of natural fibres. Three glass batches were prepared in the SiO2-CaO-P2O5-K2O-Na2O-CaF2 glass system, then melted, quenched and milled to give fine glass powders. DTA thermograms for the three glass compositions showed crystallization temperatures between 720 and 760°C and Tg ranging between 508 and 645°C. Porous glass-ceramics were characterized for bulk density, phase evolution and microstructures. Different compositions resulted in different bulk densities and phases that crystallized out. Fluorapatite …


Water Soluble Chitosan As An Environment-Friendly Coagulant In Removal Of Rubber Particles From Skim Rubber Latex, R Werathirachot, P Danwanichakul, C Kongkaew, S Loykulnant Dec 2008

Water Soluble Chitosan As An Environment-Friendly Coagulant In Removal Of Rubber Particles From Skim Rubber Latex, R Werathirachot, P Danwanichakul, C Kongkaew, S Loykulnant

Journal of Metals, Materials and Minerals

Water soluble chitosan, dissolved in hot deionized water to obtain 0.8% solution, was used for the coagulation-flocculation of skim natural rubber latex. The efficiency of coagulation-flocculation of skim rubber latex without pH adjustment was much poorer than that of neutral skim rubber latex. When adding chitosan solution to the neutral skim rubber latex with a rubber content of 5.300 %wt/vol until the concentration of chitosan in the dispersion was 0.107%, the phase separation between rubber particles and yellow serum was clearly observed. At this condition, the removal efficiency of skim rubber particles was found to be the best among all …


Fabrication Of Al/Al2o3 Composite By Powder Metallurgy Method From Aluminum And Rice Husk Ash, C Dhadsanadhep, T Luangvaranunt, J Umeda, K Kondoh Dec 2008

Fabrication Of Al/Al2o3 Composite By Powder Metallurgy Method From Aluminum And Rice Husk Ash, C Dhadsanadhep, T Luangvaranunt, J Umeda, K Kondoh

Journal of Metals, Materials and Minerals

Fabrication of Al-4wt.%Cu /Alumina composite was reported. The method of fabrication was powder metallurgy by in-situ reaction to form alumina during fabrication. Starting materials were mixture of aluminum, copper, and silica powders. Silica is in form of rice husk ash. The mixture was cold compacted, and sintered at 650°C for 1 h. Hot forging was carried out to further consolidate the sintered billet, followed by 10-h heat treatment at temperatures between 590 to 650°C. Phase analysis by XRD confirmed that in-situ reaction between silica and aluminum powders occurred during heat treatment at temperatures above 590°C. The products of reaction were …


Chitin Nanowhisker And Chitosan Nanoparticles In Protein Immobilization For Biosensor Applications, P Na Nakorn Dec 2008

Chitin Nanowhisker And Chitosan Nanoparticles In Protein Immobilization For Biosensor Applications, P Na Nakorn

Journal of Metals, Materials and Minerals

In this study, bovine serum albumin (BSA) was used as a model protein for the optimization of protein immobilization on chitin nanowhisker and chitosan nanoparticles under different conditions. Chitosan nanoparticles showed better results than chitin in this immobilization purpose. The immobilization at 15 minutes, pH 6 and 20-25°C was the optimal condition. Subsequently, glucose oxidase (GOD), enzyme used for glucose determination, was applied in order to investigate the optimum immobilization condition on chitosan nanoparticles. The optimal condition prove to…at pH 7, 30°C and 0.5 mg/ml of initial GOD concentration via immobilization at 15 minutes. Chitin nanowhisker and chitosan nanoparticles in …


Properties Evaluation Of Sodium Nitrite Treated Chitosan-Cotton Fabric, S Srisuk, K Srikulkit Dec 2008

Properties Evaluation Of Sodium Nitrite Treated Chitosan-Cotton Fabric, S Srisuk, K Srikulkit

Journal of Metals, Materials and Minerals

In this study, chitosan coated-cotton fabric was prepared and then treated with sodium nitrite under mild condition, aiming at the partial removal of surface-chitosan in order to solve the problems of surface dyeing and fabric stiffness. The results showed that sodium nitrite treated chitosan-fabric exhibited an improvement of dyeability (higher dye exhaustion and color strength) when compared to untreated fabric. The improvement in dyeability was due to the availability of chitosan amino groups which had an affinity to anionic dyes including reactive dyes. Other fabric properties were evaluated. The results showed that color fastness properties (crocking fastness and light fastness) …