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941.
A kind of novel superabsorbent hydrogel with high swelling ratio property that could be used for the development of water absorbing resin, soil water retention agent, and chemical sand‐fixing material was synthesized in this study. The hydrogels were prepared by the crosslinking reaction of polysuccinimide (PSI). The relationships between swelling ratio and volume of solvent as well as the concentration of crosslinking agent were investigated in detail. Several composites, such as starch, carrageenan, and polyacrylamide, were added into hydrogels to enhance the swelling ratio. It was found that the swelling ratio was significantly increased, which the maximum water absorbency was enhanced 2.46 times when the composite polyacrylamide (PAM) was added compared to the control. The effects of ionic strength and sensitivity of pH on hydrogels were also studied. The modified hydrogels products with swelling ratio less sensitivity to the salinity as well as relative high swelling ration in salinity system were also obtained by adding PAM. Through the Fourier transform infrared spectroscopy (FTIR) characterizations, the crosslinking reaction mechanism and the structure of composite were proposed. In addition, the transmission electron microscopy (TEM) examinations showed that some composite materials elevated the physical crosslinked and connected channels density substantially. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 102: 550–557, 2006 相似文献
942.
本文主要叙述了环氧-丙烯酸酯聚合乳液的合成,以及该乳液粘合剂的配制;讨论了该乳液粘合剂的粘合性能及耐水、耐溶剂性能。 相似文献
943.
Zeyun Yu Jun Wang Zhanheng Gao Ming Xu Masahiko Hoshijima 《Computer methods and programs in biomedicine》2014
In this paper we present a new software toolkit for generating and optimizing surface and volumetric meshes from three-dimensional (3D) biomedical imaging data, targeted at image-based finite element analysis of some biomedical activities in a single material domain. Our toolkit includes a series of geometric processing algorithms including surface re-meshing and quality-guaranteed tetrahedral mesh generation and optimization. All methods described have been encapsulated into a user-friendly graphical interface for easy manipulation and informative visualization of biomedical images and mesh models. Numerous examples are presented to demonstrate the effectiveness and efficiency of the described methods and toolkit. 相似文献
944.
PVC/TPU/NBR三元共混物的制备及性能研究 总被引:2,自引:0,他引:2
对PVC/热塑性聚氨酯(TPU)/SR三元共混物的性能进行研究,重点讨论NBR品种、TPU/NBR并用比、PVC聚合度、增塑剂DOP和硫化剂DCP用量对PVC/TPU/NBR三元共混物性能的影响。结果表明。PVC/TPU/NBR-3604三元共混物的物理性能较优;PVC/TPU/NBR-3604三元共混物的拉断伸长率和拉断永久变形均随着PVC聚合度的增大基本呈上升趋势;随着增塑剂DOP用量的增大,共混物的邵尔A型硬度、拉伸强度、撕裂强度和拉断永久变形均基本呈下降趋势,拉断伸长率增大;随着硫化剂DCP用量的增大。共混物的拉伸强度和拉断伸长率变化不大,撕裂强度基本呈逐渐减小的趋势。不同PVC/TPU/SR三元共混物的扫描电子显微镜照片表明,NBR与PVC和TPU的相容性较好。 相似文献
945.
946.
947.
Qin Zou Yu Cao Qingquan Li Qingzhou Mao Song Wang 《Machine Vision and Applications》2014,25(7):1841-1858
Recent inpainting techniques usually require human interactions which are labor intensive and dependent on the user experiences. In this paper, we introduce an automatic inpainting technique to remove undesired fence-like structures from images. Specifically, the proposed technique works on the RGBD images which have recently become cheaper and easier to obtain using the Microsoft Kinect. The basic idea is to segment and remove the undesired fence-like structures by using both depth and color information, and then adapt an existing inpainting algorithm to fill the holes resulting from the structure removal. We found that it is difficult to achieve a satisfactory segmentation of such structures by only using the depth channel. In this paper, we use the depth information to help identify a set of foreground and background strokes, with which we apply a graph-cut algorithm on the color channels to obtain a more accurate segmentation for inpainting. We demonstrate the effectiveness of the proposed technique by experiments on a set of Kinect images. 相似文献
948.
Jun Ye 《Neural computing & applications》2014,25(6):1447-1454
A trapezoidal intuitionistic fuzzy set, some operational laws, score and accuracy functions for trapezoidal intuitionistic fuzzy values are presented in this paper. Then, the trapezoidal intuitionistic fuzzy prioritized weighted averaging (TIFPWA) operator and trapezoidal intuitionistic fuzzy prioritized weighted geometric (TIFPWG) operator are proposed to aggregate the trapezoidal intuitionistic fuzzy information. Furthermore, a multicriteria decision-making method based on the TIFPWA and TIFPWG operators and the score and accuracy functions of trapezoidal intuitionistic fuzzy values is established to deal with the multicriteria decision-making problem in which the criteria are in different priority level. Finally, a practical example about software selection for considering various prioritized relationships between the criteria of decision-making is given to demonstrate its practicality and effectiveness. 相似文献
949.
The effect of adsorbed polymer on the stability of alumina suspension was investigated. Poly(ethylene oxide) (PEO), poly(acrylic
acid) (PAA) and similar kinds of polymer salts were used as a dispersant. The amount of polymer adsorbed on alumina surface
and the suspension stability was measured. The pH, molecular weight, and concentration were considered as experimental parameters.
PEO shows low affinity on the alumina surface while PAA has high affinity. In the case of PAA adsorption, the surface charge
change by polymer adsorption influences suspension stability strongly, but not in the case of PEO adsorption. In simultaneous
adsorption of PEO and PAA, the PAA concentration was fixed and PEO concentration was varied. The stability of suspension increased
with increasing PEO concentration, and this is partly due to the steric stabilization by adsorption of PAA-PEO complex or
adsorption of PEO through pre-adsorbed PAA and the depletion effect of non-adsorbed polymer. Suspension adsorbing sodium salts
of PAA and poly(methacrylic acid) (PMA) each showed similar stability. But, when the PEO and these kinds of salts were added
together to the suspension, the one with PAA sodium salt could keep a higher stability even with lower molecular weights of
PEO compared with suspension with PMA sodium salt. 相似文献
950.