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991.
民俗文化是地域景观的构成要素,民俗文化的传承对展现地域文化具有重要的意义,在城乡建设中对民俗风情的探索已经成为相关领域研究的热点。本文以西昌邛海缸窑湾度假村景观规划设计方案为例,通过对当地民俗文化从精神层面的解析,提炼成方案设计的手法,探讨如何在地域景观设计中更好地融入民俗文化要素。 相似文献
992.
993.
Epoxy asphalt (EA) binder has been used extensively for paving long‐span bridges in many countries because it shows excellent heat resistance, is free from bleeding, has a low‐temperature cracking resistance, and has aggregate scattering resistance. EA binders were prepared by the mixture of asphalt, epoxy resin, and a new curing agent (CR) with functional groups. The properties of the EA binder were characterized by their viscosity, tensile strength, elongation at break, compatibility, morphology, glass transition temperature (Tg), contact angle, and surface free energy. The curing process was analyzed. The results indicate that the curing temperature and asphalt content had significant effects on the properties of the EA binder. We observed that most of the strength was generated after the first 3 h at 165 °C; this provided good workability for EA pavement construction. The CR with various functional groups improved the compatibility and morphology of the EA binder. The test results show that Tg of the EA binder decreased and the contact angles increased with increasing asphalt content. It is worth noting the contact angles between water and the EA binder were always greater than 90°; this implied that the EA binder was hydrophobic and, hence, water repellent. The surface free energy and dispersion force increases with decreasing asphalt content. However, the polarity forces decreased with decreasing asphalt content. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016 , 133, 43401. 相似文献
994.
Proteins are amphoteric biopolymers with unevenly charged exterior surfaces. Taking this point fully into account could accomplish ingenious recognition systems for the biological macromolecues. Molecularly imprinted polymers (MIPs) are good tools to study the interactions between polymeric matrices and template molecules. Here different protein imprinted cryogels were prepared. Imprinting factors (IFs) were determined with bovine serum albumin (BSA) as the template. The IF of the polymeric cryogel made from only acrylamide (AM) and N,N′‐methylenebisacrylamide (BisAM) is about 1.38. The introduction of charged monomers, either acrylic acid or diallylamine, would increase IFs obviously. One of the basic cryogels gave the maximum IF (about 2.0) of that type. As both acrylic acid and diallylamine were involved, IFs were further increased. An amphoteric cryogel with a suitable acid‐base ratio gave a high IF of about 3.7. Whatever used alone or both, too many added acidic or basic monomers resulted in IF reduction. Taking full advantage of charged groups in MIPs could be a good way to manipulate protein–polymer interactions. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016 , 133, 43851. 相似文献
995.
Nanoemulsification of Ceramide-2 by Sodium Dilauramidoglutamide Lysine,a Novel Peptide-Based Gemini Surfactant 下载免费PDF全文
Yonghong Tian Yiguang Guo Xuefang Yang Wanping Zhang 《Journal of surfactants and detergents》2016,19(4):653-661
A novel peptide-based gemini surfactant, namely, sodium dilauramidoglutamide lysine (DLGL) was employed to fabricate a stable nanoemulsion system for the delivery of hydrophobic bioactive ceramide-2 molecules. The phase properties and morphology and stability of the nanoemulsion were investigated by focusing on the interaction between DLGL and ceramide-2 molecules. The investigation of the phase properties of the mixture of DLGL and ceramide-2 by X-ray diffraction, differential scanning calorimetry, and Fourier transform infrared spectroscopy revealed remarkable reduction in the crystallinity of ceramide-2 due to the presence of DLGL. The spherical shape and nanometer size of nanoemulsions emulsified by DLGL were characterized by scanning electron microscopy and transmission electron microscopy. The nanoemulsions prepared using DLGL exhibited significant improvement in the dispersion stability without any significant changes in the particle sizes even after storing them for a month at 50 °C. The results indicated that DLGL readily associated with ceramide-2 to form a relatively stable structure. The steric hindrance of DLGL and molecular rearrangement of DLGL and ceramide-2 attributed to a break in the continuity of the molecular assembly of ceramide-2, which hampered its crystallinity. 相似文献
996.
Yaqing Chang Xiaofei Tian Weijie Zhang Fenjie Han Shun Chen Mi Zhou Zhenguo Pang Shoubing Qi Wenping Feng 《International journal of molecular sciences》2016,17(9)
Heat tolerance is a target trait in the selective breeding of the sea urchin Strongylocentrotus intermedius, as it plays an important role in the survival and growth of cultured S. intermedius during summer. We investigated family growth and survival response to two temperature treatments to evaluate the genotype by temperature interaction (GEI) in the family selection of S. intermedius. Sea urchins from 11 families were exposed to two simulated water temperature environments—high temperature (HE) and control temperature (CE)—for 12 months, with each experiment divided into four periods (P1, stress-free period I; P2, stress-full high period; P3, stress-response period; and P4, stress-free period II) based on the temperature changes and the survival. Test diameter (TD), body weight (BW), and survival rate (SR) in HE and CE were measured monthly. Effects of family, temperature, and family-temperature interaction on TD, BW, SR, and specific growth rate (SGR) for BW were examined. In CE, BW differed significantly between families in P2, P3, and P4, while TD differed significantly between families in P3 and P4 (p < 0.05). In HE, family had significant effects on BW in P4, and on TD in P3 and P4, while temperature had significant effects on SR, TD, and BW in P3 and P4 (p < 0.05). GEI effects were not significant for TD or BW; however, family ranking changes revealed the existence of GEI in SR. The GEI results indicate the necessity of applying family selection in CE and HE for SR, but not for TD or BW. These results may provide a guide for aquaculture and selective breeding of S. intermedius under temperature pressure. 相似文献
997.
998.
本文全面系统地介绍了我国岩金矿床品位指标优化研究的最新进展:(1)多个优化目标的设置。(2)备选品位指标方案拟定的综合方法研究。(3)双指标品位-储量数学模型的建立。(4)应用现代数学方法品位指标的优化研究。(5)计算机辅助品位指标优化系统的建立。 相似文献
999.
1000.
介绍一种飞机投弹出舱过程自动记录装置。该装置没有对飞机的机械接口和电气接口进行任何改变,只需利用飞机现有挂弹架的挂弹钩接口安装设备,通过光敏开关感应光线强弱变化,判断飞机武器舱门是否打开,从而自动触发高速摄像机拍摄,完成飞机投弹出舱过程的记录任务。 相似文献