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2010

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Articles 121 - 150 of 1220

Full-Text Articles in Civil and Environmental Engineering

Arc-Spot Welds For Multi-Overlap Roof Deck Panels, N. Guenfoud, R. Tremblay, C. A. Rogers Nov 2010

Arc-Spot Welds For Multi-Overlap Roof Deck Panels, N. Guenfoud, R. Tremblay, C. A. Rogers

CCFSS Proceedings of International Specialty Conference on Cold-Formed Steel Structures (1971 - 2018)

Roof deck construction often incorporates cold-formed steel panels that are connected to the underlying framing with the use of arc-spot welds. The welds are commonly located in areas where multiple layers of roof deck exist, such as at sidelaps or endlaps. CSA S136 restricts the use of multi-layer connections to being less than 2.5 mm thick; as well, the thickness of the supporting steel must exceed 2.5 times the aggregate thickness of the deck. In effect, the standard does not allow for the use of arc-spot welds for 18 ga (1.21 mm) and 16 ga (1.52 mm) roof deck panels. …

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Cfsei Educating North American Practitioners In Principles Of Cfs Framing Design, W. D. Allen Nov 2010

Cfsei Educating North American Practitioners In Principles Of Cfs Framing Design, W. D. Allen

CCFSS Proceedings of International Specialty Conference on Cold-Formed Steel Structures (1971 - 2018)

Educating North American structural engi neers in the principles of cold-formed steel (CFS) design in general, and about CFS framing in particular, has a unique set of challenges. The undergraduate curri cula virtually ignore the subjects, and only a handful of graduate programs address the issue. Several industry associations have existed for engineers, but none specialize in CFS framing. Several organizations existed in the co ld-formed steel framing marketplace, but none were set up to accommodate engi neers. This paper will review the formation, development, growth, and maturation of one such education- and engineer-focused organization within the framework of the …

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Screw Connections Subject To Tension Pull-Out And Shear Forces, R. M. Francka, R. A. Laboube Nov 2010

Screw Connections Subject To Tension Pull-Out And Shear Forces, R. M. Francka, R. A. Laboube

CCFSS Proceedings of International Specialty Conference on Cold-Formed Steel Structures (1971 - 2018)

Currently, the behavior of screw connections subject to combined tension pull- out and shear forces is not well understood. An experimental study was conducted at Missouri Un iversity of Science and Technology to better understand the relationship or interac tion between these forces. The test program evaluated four parameters that may influence the behavior of pure tension and pure shear in screw connections: the thickness of the sheet not in contact with the screw head, the ultimate strength of the steel, the ductility of the steel, and the screw diameter. Based on the behavior observed and analysis of the test …

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Cyclic Elastoplastic Large Displacement Analysis Of Cold-Formed Steel Box Columns Under Combined Action Of Axial And Bidirectional Lateral Loading, Iraj H. P. Mamaghani, Saman Montazeri Nov 2010

Cyclic Elastoplastic Large Displacement Analysis Of Cold-Formed Steel Box Columns Under Combined Action Of Axial And Bidirectional Lateral Loading, Iraj H. P. Mamaghani, Saman Montazeri

CCFSS Proceedings of International Specialty Conference on Cold-Formed Steel Structures (1971 - 2018)

This paper deals with the cyclic elastoplastic large displacement analysis of cold-formed steel box columns under combined action of axial and bidirectional lateral loading. Cold-formed steel box columns are very useful in highway bridge pier construction as they offer flexible space requirement and provide speedy construction. Behavior of cold-formed steel box columns under earthquake-induced loads is rather complicated as earthquakes occur in an oblique direction. However, modern seismic design philosophies have been based on the behavior of structures under independent actions of uni-directional loading in orthogonal directions. In this study, inelastic cyclic behavior of steel columns subjected to constant axial …

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Experimental Investigation Of Optimized Cold-Formed Steel Compression Members, D. J. Klingshirn, E. A. Sumner, N. A. Rahman Nov 2010

Experimental Investigation Of Optimized Cold-Formed Steel Compression Members, D. J. Klingshirn, E. A. Sumner, N. A. Rahman

CCFSS Proceedings of International Specialty Conference on Cold-Formed Steel Structures (1971 - 2018)

In the past, standard C - shaped metal studs have been the only option for designers and contractors when selecting a cross section for load bearing compression members. T he sigma shaped section has recently emerged as an alternative to the C - section. The sigma shaped section is very similar to the C - shape, with the exception of having an intermediate web return and complex stiffeners. The experimental results of concentric axial compression tests of fifty - eight sigma shaped members are reported. Specimen s were tested at various lengths to force global, distortional, and local buckling failure …

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Test And Finite Element Analysis On Distortional Buckling Of Cold-Formed Thin-Walled Steel Lipped Channel Columns, Xingyou Yao, Yanli Guo, Zhiguang Huang Nov 2010

Test And Finite Element Analysis On Distortional Buckling Of Cold-Formed Thin-Walled Steel Lipped Channel Columns, Xingyou Yao, Yanli Guo, Zhiguang Huang

CCFSS Proceedings of International Specialty Conference on Cold-Formed Steel Structures (1971 - 2018)

High-strength cold-formed thin-walled steel sections have been widely used in the recent several years. However, distortional buckli ng or interaction between it and local buckling can occur for high strength cold-formed thin- walled steel members. This paper desc ribes a series of compression tests performed on lipped channel section columns with V-shape intermediate stiffener in the web and flanges fabricated from cold-formed high strength steel of thickness 0.48 and 0.6mm with nominal yield stress 550MPa. The lipped channel sections were tested to failure with both ends of the columns fixed. The test results of 16 specimens show that the local …

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Comparative Behavior Of Built-Up Cold-Formed Box Sections Under Rigid And Flexible End Support Conditions, W. Reyes, F. A. Guzman Nov 2010

Comparative Behavior Of Built-Up Cold-Formed Box Sections Under Rigid And Flexible End Support Conditions, W. Reyes, F. A. Guzman

CCFSS Proceedings of International Specialty Conference on Cold-Formed Steel Structures (1971 - 2018)

According to section D1.2 of AISI S100-2007 for compression members composed of two sections in contact whose buckling mode involves shear forces in the connectors, a reduction must be made, KL r ⁄ must be replaced by ሺ KL r ⁄ሻ ୫ . This new modified slenderness ratio takes into account the connection weld spacing and the minimum radius of gyration of an individual shape in the built-up member. Under the provisions of section D1.2 a reduction in load capacity must be made for built-up welded box members, which are the subject of this study. An experimental investigation on 48 …

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Theoretical Analysis Of Cold-Formed Steel Battened Double Angle Members Under Compression, W. F. Maia, J. Munaiar Neto, M. Malite Nov 2010

Theoretical Analysis Of Cold-Formed Steel Battened Double Angle Members Under Compression, W. F. Maia, J. Munaiar Neto, M. Malite

CCFSS Proceedings of International Specialty Conference on Cold-Formed Steel Structures (1971 - 2018)

In Brazil, battened double angle system is one of the systems most used in light truss, however, there are not any specific studies on its behavior, resulting in the fact that the standard procedures do not provide subsidies for the design of this section. Moreover, cold-formed steel si mple angles under compression, mostly with slender legs, have an interesting structural behavior compared to other cold-formed steel shapes. Two critical modes are observed in the elastic stability analysis: (i) global flexural mode in the case of longer members and (ii) a coincident local-plate/global flexural-torsional mode, which is critical for shorter members. …

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Direct Strength Design Of Cold-Formed C-Sections For Shear, Cao Hung Pham, Gregory J. Hancock Nov 2010

Direct Strength Design Of Cold-Formed C-Sections For Shear, Cao Hung Pham, Gregory J. Hancock

CCFSS Proceedings of International Specialty Conference on Cold-Formed Steel Structures (1971 - 2018)

The Direct Strength Method (DSM) rece ntly included in the North American Specification and Australian/New Zealand Standard AS/NZS 4600:2005 gives design rules for compression and bending. No rules are presente d at this stage for shear. Two series of tests on C-section can be used to develop and calibrate rules for design in shear. These are the University of Missouri Rolla tests of the 1970’s and recent tests on high strength C-sections at the University of Sydney. Both series of tests use a similar test rig altho ugh different levels of tension field action have been observed. Two features research …

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Direct Strength Design Of Cold-Formed C-Sections In Combined Bending And Shear, Cao Hung Pham, Gregory J. Hancock Nov 2010

Direct Strength Design Of Cold-Formed C-Sections In Combined Bending And Shear, Cao Hung Pham, Gregory J. Hancock

CCFSS Proceedings of International Specialty Conference on Cold-Formed Steel Structures (1971 - 2018)

The paper describes a research program including tests on both plain C- and SupaCee ® purlin sections in combined bending and shear, and bending only. The high strength SupaCee ® profile steel sections contain additional return lips and web stiffeners which enhance the bending and shear capacity of the sections. They are used widely in Austra lia as purlins in roof and wall systems. The tests were performed at the University of Sydney with and without straps on the flange and thus allowed distortional buckling in the latter case. Design methods for these sections are normally specified in the Australian/New …

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On The Direct Strength Design Of Continuous Cold-Formed Steel Beams, Cilmar Basaglia, Dinar Camotim Nov 2010

On The Direct Strength Design Of Continuous Cold-Formed Steel Beams, Cilmar Basaglia, Dinar Camotim

CCFSS Proceedings of International Specialty Conference on Cold-Formed Steel Structures (1971 - 2018)

The work reported in this paper concerns an ongoing investigation aimed at developing an efficient methodology to design continuous cold-formed steel beams failing in modes that combine local, distortional and global features. At this stage, it is intended to assess how accurately can the load-carrying capacity of lipped channel continuous (two and three-span) beams subjected to non-uniform bending be predicted by means of the current Direct Strength Method (DSM) design curves. “Exact” ultimate strength values yielded by geometrically and materially non-linear shell finite element analyses are compared with estimates provided by the DSM equations and, on the basis of this …

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Cross-Aisle Stiffness Tests On Rack Upright Frames, S. R. Sajja, R. G. Beale, M. H. R. Godley Nov 2010

Cross-Aisle Stiffness Tests On Rack Upright Frames, S. R. Sajja, R. G. Beale, M. H. R. Godley

CCFSS Proceedings of International Specialty Conference on Cold-Formed Steel Structures (1971 - 2018)

The US Rack Manufacturers Institution (RMI) code uses a theoretical formula derived by Timoshenko and the new Eurocode EN15512 requires testing. There is a considerable difference in the stiffn ess values determined by two approaches. This paper describes the experiments conducted on 80 full sized upright frames at Oxford Brookes University varying upright size, number of panels in the frame, aspect ratio of the panel (panel length/depth), restraints at the intermediate nodes of the frame, loading pattern, lacing pattern (channels back to back or front to front) and bolt tightness. The experimental data reported can be used in proposing revised …

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Experimental Evaluation Of A Vehicular Access Door Subjected To Hurricane Force Wind Pressures, Tian Gao, Christopher D. Moen Nov 2010

Experimental Evaluation Of A Vehicular Access Door Subjected To Hurricane Force Wind Pressures, Tian Gao, Christopher D. Moen

CCFSS Proceedings of International Specialty Conference on Cold-Formed Steel Structures (1971 - 2018)

This paper describes an experimental study of a rolling sheet door under uniform positive and negative pressure, i.e. wind pushing the door into the building and wind suction pulling the door out of the building. Rolling sheet vehicular access doors are a commonly provided feature in metal building systems. The edges of the door slide freely during regular usage in tracks connected to cold-formed steel jambs. During an extreme wind event, the door engages the jambs with wind locks distributed along both vertical edges of the door to prevent excessive out-of-plane deformation. The goal of the study was to measure …

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Frame Analysis And Design Of Industrial Cold-Formed Steel Racks, Teoman Pekoz, Ali Karakaplan, Ali Koç Nov 2010

Frame Analysis And Design Of Industrial Cold-Formed Steel Racks, Teoman Pekoz, Ali Karakaplan, Ali Koç

CCFSS Proceedings of International Specialty Conference on Cold-Formed Steel Structures (1971 - 2018)

Industrial cold-formed steel racks have semi-rigid joints between the columns and beams. Frame analysis of such structures call for special considerations that are studied in this paper. The current design approach uses a linear idealization of the moment-rotation relation relationship based on an empirically decided secant to the nonlinear moment rotation curve. This study presents a refined analytical approach to the analysis such frames using the state-of-art finite elemen t based nonlinear analysis program LARSA 4D. Parametric studies are carri ed out to obtain an accurate design approach for usin g computer programs that treat linear moment-rotation relationships.

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Evaluation Of The Flexural Strength Of Cold-Formed Steel Studs With Embossed Flanges, K. B. Reynolds, S. F. Stephens, Roger A. Laboube Nov 2010

Evaluation Of The Flexural Strength Of Cold-Formed Steel Studs With Embossed Flanges, K. B. Reynolds, S. F. Stephens, Roger A. Laboube

CCFSS Proceedings of International Specialty Conference on Cold-Formed Steel Structures (1971 - 2018)

New advances and improvements in the manufacture of cold-formed steel shapes are continually being made. One such advancement in the manufacturing of steel studs is flange embossing, a technique used to facilitate the installation of drywall screws into the stud flange. Currently, embossed flanges are not specifically addressed in the North American Specification for the Design of Cold-Formed Steel Structural Members (AISI S100), thereby drawing into question the use of current design equations from being used to calculate member properties for an embossed stud. A limited experimental investigation was undertaken to determine if light flange embossing affects the nominal flexural …

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Cold-Formed Steel For Students A Website, Roger A. Laboube, C. M. Stratman Nov 2010

Cold-Formed Steel For Students A Website, Roger A. Laboube, C. M. Stratman

CCFSS Proceedings of International Specialty Conference on Cold-Formed Steel Structures (1971 - 2018)

No abstract provided.

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Innovative Damage Control Systems Using Replaceable Energy Dissipating Steel Fuses For Cold-Formed Steel Structures, Fuminobu Ozaki, Yoshimichi Kawai, Hiroshi Tanaka, Tadayoshi Okada, Ryoichi Kanno Nov 2010

Innovative Damage Control Systems Using Replaceable Energy Dissipating Steel Fuses For Cold-Formed Steel Structures, Fuminobu Ozaki, Yoshimichi Kawai, Hiroshi Tanaka, Tadayoshi Okada, Ryoichi Kanno

CCFSS Proceedings of International Specialty Conference on Cold-Formed Steel Structures (1971 - 2018)

This paper describes the development of innovative seismic technologies for cold-formed steel structures; a rocking steel shear wall system with replaceable energy dissipating steel fuses for low rise housing units. In this system, the fuses are placed at the base of a folded-steel sheet wall connecting an anchor bolt and the steel sheet wall. It is designed so that most of the earthquake energy can be dissipated by plastic deformation of the fuse elements, while the shear wall remains intact and resists vertical and horizontal forces caused by large earthquakes. As expected in seismic events, the fuses at the base …

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Shear Behaviors Of Light-Gauge Composite Walls Under Monotonic And Cyclic Loading, Yuangqi Li, Fei Liu, Zuyan Shen, Xingyou Yao Nov 2010

Shear Behaviors Of Light-Gauge Composite Walls Under Monotonic And Cyclic Loading, Yuangqi Li, Fei Liu, Zuyan Shen, Xingyou Yao

CCFSS Proceedings of International Specialty Conference on Cold-Formed Steel Structures (1971 - 2018)

Shear properties of cold-formed thin-walled steel composite walls are af- fected by many factors, including the section of light-gauge studs, the space of self-drilling screws, the panel on both sides of wall, the distribution of hold down device, etc, which makes it is difficult to estimate the shear strength. In this paper, twelve Q345 light-gauge composite wall specimens with a dimension of 2400mm wide and 3000mm high were designed for shear capacity test. Two kinds of panel combination in the specimens were considered, one is gypsum board on one side and OSB board on another side, the other is gypsum …

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Wimax Implementation As Existing Hotspot Network Backhaul In Jakarta, Djamhari Sirat, Muhamad Asvial, Luther B. Marpaung Nov 2010

Wimax Implementation As Existing Hotspot Network Backhaul In Jakarta, Djamhari Sirat, Muhamad Asvial, Luther B. Marpaung

Makara Journal of Technology

WiMAX Implementation as Existing Hotspot Network Backhaul in Jakarta The development of Broadband Wireless Access (BWA), such as WiMAX, as a global standard for data transmission media has been used by high speed internet access provider. WiMAX application which supported by capabilities of interoperability, flexibility and commercial aspect make the internet services become more efficient, cheaper and easier to the customer. This phenomenon should be responded by ISPs. Based on technical and financial aspect in deciding the implementation of Wireless Network with WiMAX technology as a substitute, this research will observe and analyze the projection of WiMAX technology implementation as …

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Plant Growth Modeling Using L-System Approach And Its Visualization, Atris Suyantohadi, Alfiyan Alfiyan, Mochamad Hariadi, Mauridhi Hery Purnomo Nov 2010

Plant Growth Modeling Using L-System Approach And Its Visualization, Atris Suyantohadi, Alfiyan Alfiyan, Mochamad Hariadi, Mauridhi Hery Purnomo

Makara Journal of Technology

The visualization of plant growth modeling using computer simulation has rarely been conducted with Lindenmayer System (L-System) approach. L-System generally has been used as framework for improving and designing realistic modeling on plant growth. It is one kind of tools for representing plant growth based on grammar sintax and mathematic formulation. This research aimed to design modeling and visualizing plant growth structure generated using L-System. The environment on modeling design used three dimension graphic on standart OpenGL format. The visualization on system design has been developed by some of L-System grammar, and the output graphic on three dimension reflected on …

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Immobilization Of Saccharomyces Cerevisiae In Rice Hulls For Ethanol Production, Edita Martini, Dian Andriani, Sriramulu Gobikrishnan, Kyeong Eop Kang, Surn-Teh Bark, Changshin Sunwoo, Bambang Prasetya, Don-Hee Park Nov 2010

Immobilization Of Saccharomyces Cerevisiae In Rice Hulls For Ethanol Production, Edita Martini, Dian Andriani, Sriramulu Gobikrishnan, Kyeong Eop Kang, Surn-Teh Bark, Changshin Sunwoo, Bambang Prasetya, Don-Hee Park

Makara Journal of Technology

The whole cell immobilization in ethanol fermentation can be done by using natural carriers or through synthetic carriers. All of these methods have the same purpose of retaining high cell concentrations within a certain defined region of space which leads to higher ethanol productivity. Lignocellulosic plant substance represents one of highly potential sources in ethanol production. Some studies have found that cellulosic substances substances can also be used as a natural carrier in cell immobilization by re-circulating pre-culture medium into a reactor. In this experiment, rice hulls without any treatment were used to immobilize Saccharomyces cerevisiae through semi solid state …

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Separation Study Of Titanomagnetite Fe3-Xtixo4 From Natural Sand At Indramayu, West Java, Sunaryo Sunaryo, Iwan Sugihartono Nov 2010

Separation Study Of Titanomagnetite Fe3-Xtixo4 From Natural Sand At Indramayu, West Java, Sunaryo Sunaryo, Iwan Sugihartono

Makara Journal of Technology

Separation Study of Titanomagnetite Fe3-xTixO4 from Natural Sand at Indramayu, West Java. Titanomagnetite FeTiO4 has been obtained from metal sand which is separated from natural sand at Indramayu using magnetic separator with the magnetic field 0,3 Tesla. This method can improve titanomagnetite content from 32% to 63,6%. According to X-ray diffractometer (XRD) and data processing by general structure analyses system (GSAS) with χ2= 1,454 and Wrp = 0,1142 as correction factor of the peak to peak intensities, we conclude that χ2 about 0 and Wrp aproximately 10%. It indicates the datas with the error merely 0,1 can be accepted. Furthermore, …

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Hydrogen Absorption Induced Slow Crack Growth In Austenitic Stainless Steels For Petrochemical Pressure Vessel Industries, Ronnie Higuchi Rusli Nov 2010

Hydrogen Absorption Induced Slow Crack Growth In Austenitic Stainless Steels For Petrochemical Pressure Vessel Industries, Ronnie Higuchi Rusli

Makara Journal of Technology

Type 304L and type 309 austenitic stainless steels were tested either by exposed to gaseous hydrogen or undergoing polarized cathodic charging. Slow crack growth by straining was observed in type 304L, and the formation of α‘ martensite was indicated to be precursor for such cracking. Gross plastic deformation was observed at the tip of the notch, and a single crack grew slowly from this region in a direction approximately perpendicular to the tensile axis. Martensite formation is not a necessary condition for hydrogen embrittlement in the austenitic phase.

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Simulation On The Use Of Losat Data For Rice Field Mapping, Bambang H. Trisasongko, Dyah R. Panuju, Boedi Tjahjono, Baba Barus, Hari Wijayanto, Mahmud A. Raimadoya, Irzaman Irzaman Nov 2010

Simulation On The Use Of Losat Data For Rice Field Mapping, Bambang H. Trisasongko, Dyah R. Panuju, Boedi Tjahjono, Baba Barus, Hari Wijayanto, Mahmud A. Raimadoya, Irzaman Irzaman

Makara Journal of Technology

Simulation on the Use of LOSAT Data for Rice Field Mapping. Since the launch of LAPAN-TUBSAT satellite in 2007, Indonesia has been developing mission on earth observation missions for various applications. The next generation mission, called LAPAN-ORARI Satellite (LOSAT), is currently under development and expected to be launched in 2011. In order to facilitate the applications, a thorough assessment of the sensor should be made. This paper presents an examination of simulated LOSAT data for rice monitoring and mapping purposes coupled with QUEST statistical tree. We found that three-band simulated LOSAT data were suitable for the task with reasonably high …

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Development Of Technology Parameter Towards Shipbuilding Productivity Predictor Using Cubic Spline Approach, Bagiyo Suwasono, Sjarief Widjaja, Achmad Zubaydi, Zaed Yuliadi, I Nyoman Budiantara Nov 2010

Development Of Technology Parameter Towards Shipbuilding Productivity Predictor Using Cubic Spline Approach, Bagiyo Suwasono, Sjarief Widjaja, Achmad Zubaydi, Zaed Yuliadi, I Nyoman Budiantara

Makara Journal of Technology

Development of Technology Parameter Towards Shipbuilding Productivity Predictor Using Cubic Spline Approach. Ability of production processes associated with state-of-the-art technology, which allows the shipbuilding, is customized with modern equipment. It will give impact to level of productivity and competitiveness. This study proposes a nonparametric regression cubic spline approach with 1 knot, 2 knots, and 3 knots. The application programs Tibco Spotfire S+ showed that a cubic spline with 2 knots (4.25 and 4.50) gave the best result with the value of GCV = 56.21556, and R2 = 94.03%.Estimation result of cubic spline with 2 knots for the PT. Batamec shipyard …

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Shaft Torsional Vibration Response Of Vertical Axis Ocean Current Turbine Model Due To Torque Excitation, Adi Wirawan Husodo, I Ketut Aria Pria Utama, I Made Ariana Nov 2010

Shaft Torsional Vibration Response Of Vertical Axis Ocean Current Turbine Model Due To Torque Excitation, Adi Wirawan Husodo, I Ketut Aria Pria Utama, I Made Ariana

Makara Journal of Technology

Shaft Torsional Vibration Response of Vertical Axis Ocean Current Turbine Model Due to Torque Excitation. The current research aimed to study the torsional vibration response of Vertical Axis Ocean Current Turbine due to randomly torque excitation pattern, owing to the variety of ocean current velocity. The turbine model is composed of 3 aluminum blades of NACA 0018 connected to steel shaft. Turbine dimensions are 10 cm of chord, 1.8 cm of chamber and 100 cm of span. The variation of ocean current velocity is 0.5 m/s, 1.0 m/s, 1.5 m/s, 2.0 m/s, 2.5 m/s and 3.0 m/s. The Model has …

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Dye Sensitized Solar Cell With Conventionally Annealed And Post-Hydrothermally Treated Nanocrystalline Semiconductor Oxide Tio2 Derived From Sol-Gel Process, Akhmad Herman Yuwono, Badrul Munir, Alfian Ferdiansyah, Arif Rahman, Wulandari Handini Nov 2010

Dye Sensitized Solar Cell With Conventionally Annealed And Post-Hydrothermally Treated Nanocrystalline Semiconductor Oxide Tio2 Derived From Sol-Gel Process, Akhmad Herman Yuwono, Badrul Munir, Alfian Ferdiansyah, Arif Rahman, Wulandari Handini

Makara Journal of Technology

Dye-sensitized solar cell (DSSC) is one of the very promising alternative renewable energy sources to anticipate the declination in the fossil fuel reserves in the next few decades and to make use of the abundance of intensive sunlight energy in tropical countries like Indonesia. In the present study, TiO2 nanoparticles of different nanocrystallinity was synthesized via sol−gel process with various water to inorganic precursor ratio (Rw) of 0.85, 2.00 and 3.50 upon sol preparation, followed with subsequent drying, conventional annealing and post-hydrothermal treatments. The resulting nanoparticles were integrated into the DSSC prototype and sensitized with an organic dye made of …

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An Empirical Model For Build-Up Of Sodium And Calcium Ions In Small Scale Reverse Osmosis, Subriyer Nasir Nov 2010

An Empirical Model For Build-Up Of Sodium And Calcium Ions In Small Scale Reverse Osmosis, Subriyer Nasir

Makara Journal of Technology

A simple models for predicting build-up of solute on membrane surface were formulated in this paper. The experiments were conducted with secondary effluent, groundwater and simulated feed water in small-scale of RO with capacity of 2000 L/d. Feed water used in the experiments contained varying concentrations of sodium, calcium, combined sodium and calcium. In order to study the effect of sodium and calcium ions on membrane performance, experiments with ground water and secondary effluent wastewater were also performed. Build-up of salts on the membrane surface was calculated by measuring concentrations of sodium and calcium ions in feed water permeate and …

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The Effect Of Enzymatic Hydrolysis On The Properties Of Protein Hydrolysate From Paddy Mushroom, Niken Widya Palupi, Wiwik Siti Windrati, Tamtarini Tamtarini Nov 2010

The Effect Of Enzymatic Hydrolysis On The Properties Of Protein Hydrolysate From Paddy Mushroom, Niken Widya Palupi, Wiwik Siti Windrati, Tamtarini Tamtarini

Makara Journal of Technology

Protein hydrolysate was prepared from Paddy (Volvariella volvaceae) mushroom. Hydrolysis uses commercially protease available Protamex ™ with enzyme concentration of 0.1% (w/w). Hydrolysis was performed at three different temperatures (room temperature, 40 °C, and 50 °C) with different incubation periods (60, 90, and 120 minutes). Enzyme inactivation was done in 90 °C for 3 minutes. Yield and degree of hydrolysis ranged from 94.76% to 99.55% and 19.06% to 24.59%. Protein solubility was about 89–11,8%. The longer time of hydrolysis, the darker the color of protein hydrolysate. Protein hydrolysate which has hydrolysis at 50 °C for 120 minutes has the highest …

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Effect Of Diafiltration On Preparation Of Fermented Mung Beans Concentrate As Probiotic Savory Flavor Through Ultrafiltration Membrane, Aspiyanto Aspiyanto, Agustine Susilowati Nov 2010

Effect Of Diafiltration On Preparation Of Fermented Mung Beans Concentrate As Probiotic Savory Flavor Through Ultrafiltration Membrane, Aspiyanto Aspiyanto, Agustine Susilowati

Makara Journal of Technology

Diafiltration by means of the ultrafiltration system of probiotic fermented Mung beans (Phaseolus radiatus L.) concentrate has been performed to reduce or eliminate salts and smaller impurities than the nominal cut-off of the membrane of 20,000 nominal weight cut-off (NWCO). These processes have been conducted as an attempt in order to get a probiotic product with organoleptic acceptability, composition, and the optimal total lactic acid bacteria (LAB) counts because the presence of salts will affect on the viability of LAB and the cell lysis of LAB and limit its utility in food products. Concentrate of probiotic mung beans was prepared …

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