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John F. Scamehorn Edwin E. Tucker Hatice Gecol Napaporn Komesvarakul Lorena K. Serventi Kirk H. Raney Stephen F. Capps 《Journal of surfactants and detergents》2007,10(4):287-299
This study presents a method to develop an efficient and economical system for cleaning home laundry on a commercial scale
with both water and chemical (detergent) reuse. The experiments were done using an industrial-type horizontal-axis machine,
two leading consumer heavy-duty liquid laundry detergents, one I&I detergent formulation, and chlorine bleach. The technical
feasibility of reusing laundry water at high levels without significant deterioration in detergency was established in this
study. Warm water (40 °C) was used in the wash cycle, and cold water (29 °C) was used for three rinse cycles. In the integrated
process, waters from wash and rinse steps were treated using tubular microfiltration units with 0.1 μm pore size to remove
particles and emulsion droplets. These recovered waters were recycled to be reused. In addition, water recycled from the wash
step contains surfactants that can be reused. In order to simulate a large-scale industrial laundry operation at steady-state,
the batch process used here was operated six times in sequence; wash and rinse waters were filtered after each cycle and reused
in the next wash cycle. The surfactant recovery is over 40%. Soiled test strips were used to measure the percentage of soil
removal after the wash/filtration sequence for stains and various liquid or particulate soils. The soil removal remained practically
constant under simulated steady-state conditions even with water recoveries of nearly 90%. Softness of towels remained unchanged
when recycled water was used in this process. Chlorine carry-over from white laundry to the wash process was shown to be minimal.
This is important to avoid color fading in mixed loads upon reuse since water is not segregated for colored laundry versus
white laundry. Hardness ions can precipitate fatty acids which reduce flux during filtration and decrease surfactant recovery.
Preliminary analysis of the different formulations used indicates that an all-nonionic formulation may be best suited to this
recycling process.
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John F. ScamehornEmail: |
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Tapioca starch was partially hydrolyzed by 6 % and 12 % hydrochloric acid (w/v) at room temperature for various length of time. The gelatinization transitions of the acid‐modified tapioca starches were studied using Differential Scanning Calorimetry. Starch suspensions (67 % moisture) were heated at 5 °C/min to follow melting transition of amylopectin. As the hydrolysis time increased, onset (To), peak (Tp) and conclusion (Tc) temperatures of gelatinization have been observed to increase, in the same order of relative crystallinity, until reaching some critical values, then decreased with the large broadening of the endotherms. The increasing of the transition temperatures corresponded to the retrogradation of the remaining partially hydrolyzed amylose followed by a decrease of these parameters corresponding to the reduction of the length of the chains of double helices amylopectin. 相似文献
4.
Chayanin Na-Chiangmai Napaporn Tiengchad Prathan Kittisakmontree Okorn Mekasuwandumrong Jonathan Powell Joongjai Panpranot 《Catalysis Letters》2011,141(8):1149-1155
Abstract
An ultra-large pore mesocellular foam silica (MCF) was employed as a support for preparation of supported Pd catalysts for the liquid-phase selective hydrogenation of phenylacetylene. The catalysts were prepared by three different routes: (i) incipient wetness impregnation using Pd(II)acetate solution (Pd/MCF-imp), (ii) impregnation of colloidal Pd nanoparticles obtained by the solvent reduction method (Pd/MCF-col), and (iii) in situ synthesis of MCF in the presence of the Pd colloid (Pd/MCF-ss). The conventional impregnation method resulted in more agglomeration of Pd particles and partial collapse of MCF structure, hence the Pd/MCF-imp exhibited the lowest selectivity towards styrene at total conversion of phenylacetylene. Only the Pd/MCF-ss, in which most of the Pd nanoparticles were encapsulated by the silica matrix, was found to retain high styrene selectivity (>80%) after complete conversion of phenylacetylene. Comparing to the other highly efficient Pd catalysts reported in the literature under similar reaction conditions, it can be emphasized that coverage of Pd surface by the support produces great beneficial effect for enhancing styrene selectivity, regardless of the type of supports used (i.e., TiO2, carbon nanotubes, or mesostructured silica). 相似文献5.
Tira Foran Peter T. du Pont Panom Parinya Napaporn Phumaraphand 《Energy Efficiency》2010,3(4):347-364
Between 1995 and 2008, Thailand’s energy efficiency programs produced an estimated total of 8,369 GWh/year energy savings
and 1,471 MW avoided peak power. Despite these impressive saving figures, relatively little future scenario analysis is available
to policy makers. Before the 2008 global financial crisis, electricity planners forecasted 5–6% long-term increases in demand.
We explored options for efficiency improvements in Thailand’s residential sector, which consumes more than 20% of Thailand’s
total electricity consumption of 150 TWh/year. We constructed baseline and efficient scenarios for the period 2006–2026, for
air conditioners, refrigerators, fans, rice cookers, and compact fluorescent light bulbs. We drew on an appliance database
maintained by Electricity Generating Authority of Thailand’s voluntary labeling program. For the five appliances modeled,
the efficiency scenario results in total savings of 12% of baseline consumption after 10 years and 29% of baseline after 20 years.
Approximately 80% of savings come from more stringent standards for air conditioners, including phasing out unregulated air
conditioner sales within 6 years. Shifting appliance efficiency standards to current best-in-market levels within 6 years
produces additional savings. We discuss institutional aspects of energy planning in Thailand that thus far have limited the
consideration of energy efficiency as a high-priority resource. 相似文献
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Pongthipun Phuengphai Thapanee Singjanusong Napaporn Kheangkhun Amnuay Wattanakornsiri 《水科学与水工程》2021,14(4):286-294
Fruit peels, which are common agricultural byproducts, have been extensively used as abandoned or low-cost biosorbents to remove heavy metals. In this study, dragon fruit peel (DFP), rambutan peel (RP), and passion fruit peel (PFP) were used to remove Cu(II) ions from an aqueous solution. Concentrations of the adsorbed metal ions were determined using the atomic absorption spectroscopic method. Adsorption experiments were performed with different adsorbent dosages, pH values, contact times, and initial copper concentrations. The optimum set of conditions for biosorption of Cu(II) ions was found to be an adsorbent dosage of 0.25 g, a contact time of 180 min, an initial concentration of 100 mg/L, a pH value of 4 for RP and PFP, and a pH value of 5 for DFP. The adsorption conformed with the pseudo-second-order kinetic model. The adsorption data were consistent with the Langmuir and Freundlich isotherm models, but the best fit was with the Langmuir model. The Langmuir monolayer adsorption capacity values of DFP, RP, and PFP were calculated to be 92.593, 192.308, and 121.951 mg/g, respectively. RP showed a higher adsorption capacity of Cu(II) ions than PFP and DFP for all parameters. The results indicate that these biosorbents might be used to effectively adsorb Cu(II) ions from wastewater treatment plants. 相似文献
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Witawat Rungjiratananon Yoshihiro Kanamori Napaporn Metaaphanon Yosuke Bando Bing‐Yu Chen Tomoyuki Nishita 《Computer Animation and Virtual Worlds》2012,23(2):113-124
String‐like objects in our daily lives, for example shoelaces, threads, rubber cords, plastic fiber and spaghetti, have a wide variety of materials. Such string‐like objects also exhibit interesting behaviors such as twisting, tearing (by stretching or twisting), and bouncing back when pulled and released. In this paper, we present a method that enables these behaviors and simulates such materials in traditional string simulation methods that explicitly represent a string by particles and segments. Specifically, we offer the following three contributions. First, we introduce a method for handling twisting effects with both uniform and non‐uniform torsional rigidities. Second, we propose a method for estimating the tension acting on inextensible strings in order to reproduce tearing and flicking (bouncing back), whereas the tension for an extensible object can be computed via stretched length. The length of an inextensible object is maintained constant in general, and thus, we need a novel approach. Third, we introduce an optimized grid‐based collision detection for accelerating the computation. We demonstrate that our method can produce visually plausible animations of string‐like objects with various material properties, and it is a fast framework for interactive applications such as games. Copyright © 2012 John Wiley & Sons, Ltd. 相似文献
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Napaporn Metaaphanon Yosuke Bando Bing‐Yu Chen Tomoyuki Nishita 《Computer Graphics Forum》2009,28(7):1837-1844
Woven cloth can commonly be seen in daily life and also in animation. Unless prevented in some way, woven cloth usually frays at the edges. However, in computer graphics, woven cloth is typically modeled as a continuum sheet, which is not suitable for representing frays. This paper proposes a model that allows yarn movement and slippage during cloth tearing. Drawing upon techniques from textile and mechanical engineering fields, we model cloth as woven yarn crossings where each yarn can be independently torn when the strain limit is reached. To make the model practical for graphics applications, we simulate only tearing part of cloth with a yarn‐level model using a simple constrained mass‐spring system for computational efficiency. We designed conditions for switching from a standard continuum sheet model to our yarn‐level model, so that frays can be initiated and propagated along the torn lines. Results show that our method can achieve plausible tearing cloth animation with frayed edges. 相似文献
9.
Tapioca starch was partially hydrolyzed by 6% (w/v) hydrochloric acid at room temperature for various lengths of time. Annealing and freeze‐thaw stability of the acid‐modified starches were studied using Differential Scanning Calorimetry (DSC). In the annealing study, as the hydrolysis time increased, the effect of annealing on narrowing and shifting the endothermic peak to a higher temperature was decreased. The endothermic transition of annealed 48‐h acid‐modified tapioca starch showed a narrow peak and a broad shoulder, corresponding to the melting of the amylopectin double helices (crystalline regions) and the retrograded partially hydrolyzed amylose, respectively. This effect of annealing on the sharpening of the endotherm was less pronounced on acid‐modified tapioca starches annealed for 192 h and 768 h, respectively. These results indicated that annealing leads to more homogeneous crystallites and this effect is enhanced when the material contains more amorphous and homogeneous domains. In the case of the freeze‐thaw stability study, the melting endotherm of recrystallized amylopectin became larger with increasing hydrolysis time. The first detectable endotherm of native tapioca retrograded gel was observed after five cycles, while all acid‐modified retrograded gels showed the melting endotherm after only one cycle. Increasing hydrolysis time may increase the proportion of short chain amylose and amylopectin molecules, which are able to form double helices, resulting in an increase in the enthalpy and a higher retrogradation rate of the gel. 相似文献
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Napaporn Tiengchad Okorn Mekasuwandumrong Chayanin Na-Chiangmai Patcharaporn Weerachawanasak Joongjai Panpranot 《Catalysis communications》2011,12(10):910-916
Three types of mesostructured silica with different pore sizes (MCM-41, SBA-15, and MCF) were employed as supports for deposition of colloidal Pd nanoparticles obtained by the solvent reduction method. As determined by transmission electron microscopy (TEM), average Pd particle sizes on the various supports were quite similar and were not significantly different from the colloidal particles (~ 2.3–2.5 nm). There was limited access of the reactants to Pd active sites and suppression of CO chemisorption for the Pd/SBA-15, probably because most of the Pd particles were located inside the pores. This geometrical confinement effect in the case of Pd/SBA-15, however, resulted in an improved selectivity towards styrene at complete conversion of phenylacetylene. Such effect was similar to those reported in the literature for the Pd nanoparticles encapsulated in support matrices (simultaneous synthesis) and the presence of strong metal-support interaction effect in Pd/TiO2. 相似文献