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21.
In Yang Monlin Kuo Deland J. Myers 《Journal of the American Oil Chemists' Society》2006,83(3):239-245
Chromated copper arsenate (CCA), an arsenicbased wood preservative, is toxic to human health and the environment. Although
CCA is stable in seasoned wood, there are potential dangers during CCA manufacture, lumber treatment, and waste disposal.
This research was conducted to study the effectiveness of soy products to replace toxic chromium and arsenic compounds in
wood preservative formulations. Three soy product (Arpro 2100, HM 90, and Supro 760) were used as fixative agents in preservative
solutions containing anhydrous CuSO4 and Na2B4O7·10H2O. The decay resistance of treated wood blocks was measured by a soil-block culture method. Despite the large molecular sizes
of copper-protein and copper-boron-protein complexes, southern pine sapwood was treatable with these preservative formulations.
Wood samples treated with >6 kg°m−3 CuSO4 and 7.5 kg·m−3 soy product, and subsequently leached for 3 d and exposed to the decay fungus Gloeophyllum trabeum (Fr.) Mur., sustained only 0.5% weight loss over 12 wk. Wood samples needed 40 kg·m−3 CuSO4 and 50 kg·m−3 soy protein to resist the copper-tolerant decay fungus Postia placenta (Fr.) M. Lars. & Lomb. These results suggest that soy-based wood preservatives can prevent wood products from fungal attack
and can replace CCA. 相似文献
22.
In Gwun Jang Kyung-Soo Kim Byung Man Kwak 《Structural and Multidisciplinary Optimization》2014,50(3):505-515
The Mobile Harbor (MH) has been recently proposed as a novel maritime cargo transfer system that can move to a container ship anchored in the deep sea and handle containers directly at sea with the aid of a stabilized MH crane. Because this system operates under at-sea conditions, the MH crane must be designed to support an inertia load and wind force, as well as its self-weight. The wave-induced motions of the MH, e.g. rolling, pitching, and heaving, generate a significant amount of inertia load, which has not been considered in the design of conventional quayside cranes installed on stable ground. Wind force is also a critical design factor due to the higher wind velocity in the open sea. In addition to the aforementioned structural rigidity, mass minimization is also important in the structural design of MH cranes because it reduces the overturning moment and therefore enhances ship stability. In this paper, the sensitivities of the design-dependent loads (i.e. self-weight, inertia load, and wind force) are derived with respect to the design variables, and then a topology optimization is conducted with the derived sensitivities in order to obtain a conceptual design. Then, the conceptual design is elaborated into a three-dimensional basic design through shape optimization with design regulations for offshore cranes. Through the integrated design process with the topology and shape optimizations, a conceptual and basic design is successfully obtained for the MH crane. 相似文献
23.
Polyvinylpyrrolidone (PVP)/sodium montmorillonite (MMT) nanocomposites prepared via the solution intercalation method were investigated by UV/vis, SEM, X-ray diffraction, TEM, FT-IR and PLM (polarized light microscopy). PVP/MMT nanocomposites show exfoliation below 20 wt% MMT and intercalation above this concentration. Nanocomposites retain good optical clarity and increased thermal resistance with MMT content. The compatibility between PVP and MMT and their enhanced properties may be explained by hydrogen bonding interactions. In addition, the nanocomposites prepared under more rigorous mixing conditions show better transparency because the smaller particle sizes are induced. In addition, the study on optically clear PVP/MMT suspensions helps one to understand how optical anisotropy of MMT is affected by the existence of polymer in aqueous solution. 相似文献
24.
In this study the methyl tert-butyl ether (MTBE) decomposition over H3PW12O40 was carried out in a cellulose acetate membrane reactor. The permeability of methanol through the cellulose acetate membrane was about 30 and 300 times higher than that of either isobutene or MTBE, respectively. The isobutene selectivity in the fixed bed reactor was only slightly higher than the methanol selectivity due to the side reaction. In the cellulose acetate membrane reactor, however, the isobutene selectivity in the rejected stream was 68% and the methanol selectivity in the permeated stream was up to 97%. The MTBE conversion in the membrane reactor was about 7% higher than that in the membrane-free fixed bed reactor under the same reaction conditions. The enhanced performance of the membrane reactor in this reversible reaction was mainly due to the selective permeation of methanol which resulted in a methanol-deficient condition suppressing MTBE synthesis reaction. 相似文献
25.
Interpenetrating polymer network (IPN) hydrogels based on poly(ethylene oxide) and poly(methyl methacrylate) were prepared by radical polymerization using 2,2‐dimethyl‐2‐phenylacetophenone and ethylene glycol dimethacrylate as initiators and crosslinkers, respectively. The IPN hydrogels were analyzed for sorption behavior at 25°C and at a relative humidity of 95% using dynamic vapor sorption. The IPN hydrogels exhibited a relatively high equilibrium water content in the range of 13–68%. The state of water in the swollen IPN hydrogels was investigated using differential scanning calorimetry. The free water in the hydrogels increased as the hydrophilic content increased. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 89: 258–262, 2003 相似文献
26.
In Kim 《乙烯基与添加剂工艺杂志》2007,13(2):71-75
Electrically conductive acrylonitrile‐butadiene rubbers (NBRs) containing carbon black (CB) as conductive filler were prepared in order to investigate their electrical and mechanical properties. The effects of conductive CB loading, temperature, acrylonitrile content, crosslinking density of vulcanizates, and plasticizer on conductivity were studied. The change in electrical conductivity of NBRs with different amounts of CB showed that there is a certain critical point (percolation threshold) where a significant decrease in electrical resistivity (increase in conductivity) is observed. Mechanical properties such as tensile strength, elongation to break, and surface hardness of vulcanized NBRs were measured. It was found that the percolation threshold was 5 phr of CB for the NBR/CB composites. J. VINYL ADDIT. TECHNOL., 13:71–75, 2007. © 2007 Society of Plastics Engineers. 相似文献
27.
Yoon -Suk Choi Sung -Joon Kim Ik -Min Park Kwang -Woo Kwon In -Suk Yoo 《Metals and Materials International》1997,3(2):118-124
Boron distribution in a low-alloy steel (15B26:0.25C-0.29Cr-0.03Ti-0.028Al-0.0016B) has been characterized employing Fission
Track Etching (FTE) method. The characteristics of boron distribution with variation of cooling rate after austenitization
and through case-hardened depth after carburization were analyzed. Hardenability of 15B26 steel was also evaluated through
Jominy-end-quench test and the results are as follows: It was observed that, in austenitized 15B26 steel, boron was distributed
uniformly over the whole area of specimen with a little segregation along the austenite grain boundaries at higher cooling
rates and boron precipitates were formed in the intergranular as well as transgranular regions at lower cooling rates. Jominy
equivalents (HRC 35) of 15B26 steel were fairly increased between the Jominy temperatures of 820°C and 850°C, which might
result from the increase of the amount of soluble boron in austenite due to the dissolution of borocarbides between 820°C
and 850°C. In carburized 15B26 steel, the different through thickness features of boron distribution from the carburized surface
were found; coarse nodular boron precipitates up to the depth of 150 μm; uniform distribution of dissolved boron between 150~650
μm; and segregation of boron atoms along grain boundaries in the regions deeper than 650 μm. 相似文献
28.
Tuan Anh Tran In Seop Na Soo Hyung Kim 《International Journal on Document Analysis and Recognition》2016,19(3):191-209
Document layout analysis or page segmentation is the task of decomposing document images into many different regions such as texts, images, separators, and tables. It is still a challenging problem due to the variety of document layouts. In this paper, we propose a novel hybrid method, which includes three main stages to deal with this problem. In the first stage, the text and non-text elements are classified by using minimum homogeneity algorithm. This method is the combination of connected component analysis and multilevel homogeneity structure. Then, in the second stage, a new homogeneity structure is combined with an adaptive mathematical morphology in the text document to get a set of text regions. Besides, on the non-text document, further classification of non-text elements is applied to get separator regions, table regions, image regions, etc. The final stage, in refinement region and noise detection process, all regions both in the text document and non-text document are refined to eliminate noises and get the geometric layout of each region. The proposed method has been tested with the dataset of ICDAR2009 page segmentation competition and many other databases with different languages. The results of these tests showed that our proposed method achieves a higher accuracy compared to other methods. This proves the effectiveness and superiority of our method. 相似文献
29.
Motion capture cannot generate cartoon‐style animation directly. We emulate the rubber‐like exaggerations common in traditional character animation as a means of converting motion capture data into cartoon‐like movement. We achieve this using trajectory‐based motion exaggeration while allowing the violation of link‐length constraints. We extend this technique to obtain smooth, rubber‐like motion by dividing the original links into shorter sub‐links and computing the positions of joints using Bézier curve interpolation and a mass‐spring simulation. This method is fast enough to be used in real time. 相似文献
30.
A hidden‐picture puzzle contains objects hidden in a background image, in such a way that each object fits closely into a local region of the background. Our system converts image of the background and objects into line drawing, and then finds places in which to hide transformed versions of the objects using rotation‐invariant shape context matching. During the hiding process, each object is subjected to a slight deformation to enhance its similarity to the background. The results were assessed by a panel of puzzle‐solvers. 相似文献