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51.
尹浩然 《重庆科技学院学报(社会科学版)》2011,(1):70-72
作为凯恩斯主义的反对者,新自由主义以抵制政府干涉,提倡自由市场竞争的面目出现,在一定程度上被看做是对古典自由主义的复辟,但它绝不仅仅是对古典"放任自由"的一种简单继承。对新自由主义主流学派关于政府与市场理论进行考察,理清新自由主义理论思想,从而对其有一个更客观的认识和评价。 相似文献
52.
Yong Min Lee 《Electrochimica acta》2006,52(4):1582-1587
Highly ion-conductive solid polymer electrolyte (SPE) based on polyethylene (PE) non-woven matrix is prepared by filling poly(ethylene glycol) (PEG)-based crosslinked electrolyte inside the pores of the non-woven matrix. The PE non-woven matrix not only shows good mechanical strength for SPE to be a free-standing film, but also has very porous structure for high ion conductivity. The ion conductivity of SPE based on PE non-woven matrix can be enhanced by adding sufficient non-volatile plasticizer such as poly(ethylene glycol) dimethyl ether (PEGDME) into ion conduction phase without sacrificing mechanical strength. SPE with 20 wt.% crosslinking agent and 80 wt.% non-volatile plasticizer shows 3.1 × 10−4 S cm−1 at room temperature (20 °C), to our knowledge, which is the highest level for SPEs. It is also electrochemically stable up to 5.2 V and has high transference number about 0.52 due to the introduction of anion receptor as an additive. The interfacial resistance between Li electrode and SPE is low enough to perform charge/discharge test of unit cell consisting of LiCoO2/SPE/Li at room temperature. The discharge capacity of the unit cell shows 87% of theoretical value with 86% Coulombic efficiency. 相似文献
53.
The effects of coupling agents, silicone oil, and three types of polymeric modifiers on the mechanical properties of linear low density polyethylene (LLDPE) composites highly filled with aluminium hydroxide [Al(OH)3] were studied. Polymeric modifiers that contain polar groups, such as silane‐grafted polyethylene (Si‐g‐PE) and acrylic‐acid‐grafted ethylene‐vinyl acetate copolymer (AA‐g‐EVA), improve the mechanical properties dramatically, while nonpolar modifiers improve them to some extent. When Al(OH)3 was treated using a titanate coupling agent, the silicone oil increased the impact strength and elongation at break of the LLDPE/Al(OH)3 composites. Introduction of a polymeric modifier containing polar groups destroys the beneficial effects of silicone oil on film mechanical properties, while the introduction of a nonpolar elastomeric polymeric modifier retains the high impact strength and elongation at break. SEM analyses provide the indirect evidence of the encapsulation of silicone oil around the filler. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 83: 121–128, 2002 相似文献
54.
Sun Zhuojin Wang Yong Gong Chen Laganiére Robert 《Multimedia Tools and Applications》2021,80(4):5351-5372
Multimedia Tools and Applications - Recently, there are lots of tracking methods proposed to improve the performance of visual tracking in videos with challenging situations, such as background... 相似文献
55.
56.
Information Systems Frontiers - System logs that trace system states and record valuable events comprise a significant component of any computer system in our daily life. Each log contains... 相似文献
57.
International Journal of Control, Automation and Systems - In this paper, the stability issue of networked system with dynamical topology in intelligent vehicle is studied. The systems are... 相似文献
58.
JianKui Chen ZhouLong Xu YongAn Huang YongQing Duan ZhouPing Yin 《中国科学:技术科学(英文版)》2016,59(11):1646-1655
The serious warpage issues of ultrathin chip-on-flex (UTCOF) assembly induced by mismatched thermal stresses have greatly affected the mechanical stability and reliability of emerging ultrathin chip packaging technology. Currently, a theoretical prediction as a convenient and straightforward approach is still lacked for describing effectively the thermal-mechanical behavior of UTCOF during the adhesive curing and cooling process. In consideration of the adhesive thickness approximating to ultrathin chip and flexible substrate thickness, we develop a layerwise-model of ultrathin chip-adhesive-flex structure under plain strain condition, where the behavior of thick adhesive bonding can be described precisely through increasing the subdivided mathematical plies. Further, the analytical results show that the concave and convex forms of ultrathin chip warpage yield at the end of the curing and cooling process respectively. Meanwhile, the effects of its structure dimensions and material properties are also revealed for discussing a way to relieve the extent of ultrathin chip warpage. Additionally, in order to verify the validity of the theoretical prediction, we also introduce the corresponding numerical technique and experimental method. These results suggest that a kind of rigid and ultrathin flexible substrate such as metal foil should be adopted for small warpage of ultrathin assembly. 相似文献
59.
张勇 《武汉理工大学学报(材料科学英文版)》2014,29(3):561-566
A new kind of composite buffering material was made by filling the voids of honeycomb paperboard with polyurethane. Drop tests were performed to evaluate the dynamic energy absorption capacity of the material. Based on the tests results, we analyzed the mechanical behaviors of the material under different conditions and obtained the inherent influencing laws of some factors on the material's dynamic buffering performance. It was shown that the dynamic buffering performance varied directly with impact velocity, and inversely with the void diameter, thickness and buffeting area of the composite material. 相似文献
60.
The partial phase diagrams of the systems ZrO2-CaO and ZrO2-MgO were determined using precision lattice parameter measurements in order to check uncertainties reported in the literature.
The results are in general agreement with the previous investigations by Hellmann and Stubican [83HeI], Grain [67Gra], and
Sim and Stubican [87Sim]. Enthalpies of formation of the fluorite cubic solid solution and the Ca26Zr19O44 ordered phase, with reference to the monoclinic zirconia and the periclase forms of CaO and MgO, were measured calorimetrically.
Assessment of the thermodynamic properties of these two systems shows that it is appropriate to model the systems with a simple
single cation sublattice model. The eutectoid of the cubic phase in ZrO2-CaO, according to both the optimization and the experimental results, is located at 1412 ± 50 K and 16.2 ±1.0 mol% CaO and
in the ZrO2-MgO binary at 1678 ± 5 K and 13.1 ± 0.5 mol% MgO. The calculated phase diagrams are presented for comparison with the experimental
results. 相似文献