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排序方式: 共有304条查询结果,搜索用时 250 毫秒
21.
为解决整流叶片毛边起皱,叶片工作型面易被后工序切掉等问题。将叶片截面理论数据、冷轧模截面测量数据、冷轧模截面理论数据进行对比分析。对冷轧模的毛边面和过渡面进行了优化,使其曲率接近一致,同时加大过渡面的宽度。生产验证,该模具彻底消除了叶片起皱,并缩短了修模时间30%左右。 相似文献
22.
EPC球形铸铁件的皱皮缺陷分析 总被引:3,自引:0,他引:3
简述了EPC负压铸造在生产球形铸铁件过程中,浇注时,EPS的热变形和皱皮缺陷的形成,提出了减轻和防止皱皮的一些措施。 相似文献
23.
介绍了生物酶在毛纺针织制品防缩整理中的作用机理及其在实际生产中进行处理的参考工艺配方。通过预处理结合生物酶处理来改善羊毛纤维表面鳞片层物质结构与羊毛织物的性能。分析表明,该方法使羊毛表层的类脂物质去除和胱氨酸二硫键断裂,增加蛋白酶分子与羊毛蛋白的可及度,同时酶水解反应能够持续进行,显著改善了羊毛织物的润湿性,增强对化学助剂的吸附和渗透,经柔软处理后织物手感得到改善,同时提高了抗起毛起球性。 相似文献
24.
25.
为研究聚酯(PET)长丝/棉复合纱斜纹织物的保形性及服用性能,利用PET长丝与纯棉纱开发了3种线密度为9.8 tex的纱线,并以二上二下斜纹组织织造了4种织物。对织物进行了折皱回复性、免烫性、尺寸稳定性、悬垂性等保形性能,强伸性、拉伸弹性、顶破性等抗变形性测试,以及手感风格、透湿性、透气性等服用性能测试。对比分析了纯棉纱织物与复合纱织物的保形性与服用性能。结果表明:PET长丝/棉复合纱可改善纯棉织物的折皱回复性、悬垂性,提高免烫等级,同时又不影响织物的服用性能;包芯纱织物比包缠纱织物有更好的保形性,更高的免烫等级,是免烫衬衫面料的理想选择。 相似文献
26.
Kai‐Ming Hu Yun‐Qi Liu Liang‐Wei Zhou Zhong‐Ying Xue Bo Peng Han Yan Zeng‐Feng Di Xue‐Song Jiang Guang Meng Wen‐Ming Zhang 《Advanced functional materials》2020,30(34)
Obtaining a delamination‐free wrinkled functional graphene surface in layered systems is an interesting challenge because the interface is usually too weak to withstand interfacial stress mismatch, which can trigger mechanical instability. In this paper, a general strategy is proposed toward addressing the delamination limitation imposed by fabricating conformal graphene wrinkles with bilayer systems of poly(methyl methacrylate) (PMMA) and polydimethylsiloxane (PDMS). To improve the interfacial strength, a postcuring transfer process is introduced to form a gradient interface layer without interfacial liquid between the PMMA and PDMS by entanglement of polymer chains during high‐temperature curing. Compared to the conventional wet transfer of graphene,the transfer method can greatly enhance the interfacial strength. The chemical and mechanical mechanisms underlying the enhancement are revealed both experimentally and theoretically in terms of the transition from the buckled‐induced delamination state to the delamination‐free wrinkled state. Moreover, the light diffraction behaviors of multiscale graphene wrinkles are initially demonstrated to be an interesting continuous pattern induced by overlapping. The delamination‐free conformal wrinkled functional graphene surface can provide valuable insight and design guidelines for the fundamental problems of deformed graphene and its applications in flexible functional devices. 相似文献
27.
Saman Heydari Saeed Ghanbarzadeh Behzad Anoush Mohammadreza Ranjkesh Yousef Javadzadeh Maryam Kouhsoltani 《Drug development and industrial pharmacy》2017,43(7):1154-1162
Background: Free radical scavengers and antioxidants, with the main focus on enhanced targeting to the skin layers, can provide protection against skin ageing.Objective: The aim of the present study was to prepare nanoethosomal formulation of gammaoryzanol (GO), a water insoluble antioxidant, for its dermal delivery to prevent skin aging.Methods: Nanoethosomal formulation was prepared by a modified ethanol injection method and characterized by using laser light scattering, scanning electronic microscope (SEM) and X-ray diffraction (XRD) techniques. The effects of formulation parameters on nanoparticle size, encapsulation efficiency percent (EE%) and loading capacity percent (LC%) were investigated. Antioxidant activity of GO-loaded formulation was investigated in vitro using normal African green monkey kidney fibroblast cells (Vero). The effect of control and GO-loaded nanoethosomal formulation on superoxide dismutase (SOD) and malondialdehyde (MDA) content of rat skin was also probed. Furthermore, the effect of GO-loaded nanoethosomes on skin wrinkle improvement was studied by dermoscopic and histological examination on healthy humans and UV-irradiated rats, respectively.Results: The optimized nanoethosomal formulation showed promising characteristics including narrow size distribution 0.17?±?0.02, mean diameter of 98.9?±?0.05?nm, EE% of 97.12?±?3.62%, LC% of 13.87?±?1.36% and zeta potential value of –15.1?±?0.9?mV. The XRD results confirmed uniform drug dispersion in the nanoethosomes structure. In vitro and in vivo antioxidant studies confirmed the superior antioxidant effect of GO-loaded nanoethosomal formulation compared with control groups (blank nanoethosomes and GO suspension).Conclusions: Nanoethosomes was a promising carrier for dermal delivery of GO and consequently had superior anti-aging effect. 相似文献
28.
Tobias Müller Alexander Lenske Marek Hauptmann Jens‐Peter Majschak 《Packaging Technology and Science》2017,30(11):703-710
The visual and mechanical quality of paperboard packaging components formed by deep drawing closely corresponds to the wrinkle distribution within the material wall section. Assessing this quality of paperboard packaging components currently relies on very slow or even subjective methods. Therefore, counting the number of wrinkles and measuring the mean distance between wrinkles proved to be a sensitive strategy for the evaluation of quality levels in deep drawing formed paperboard containers like cups or trays. A method introduced by Hauptmann proposes the measurement of the distances between 10 wrinkles in machine direction and 10 wrinkles in cross direction for each sample. However, this method is unsatisfactory because it can only observe a small part of each sample and is subject to deviation through the individual judgement of the person carrying out the survey. Further methods, as well as their respective application range, are listed in Table 1 . Hence, it is desirable to automate the wrinkle survey to be carried out without operator influences to the measurement. This paper introduces such an automated measuring method. The given method relies on recording the sample surface topography through laser‐distance measurement. An evaluation algorithm, which enables the detection of wrinkles in the topographic data, is proposed. Furthermore, it is shown that the method yields feasible results and is capable of generating reliable quality information in considerably reduced time frames. 相似文献
29.
Jung Hwa Kim Se‐Yang Kim Yeonchoo Cho Hyo Ju Park Hyeon‐Jin Shin Soon‐Yong Kwon Zonghoon Lee 《Advanced materials (Deerfield Beach, Fla.)》2019,31(15)
Van der Waals (vdW) epitaxy allows the fabrication of various heterostructures with dramatically released lattice matching conditions. This study demonstrates interface‐driven stacking boundaries in WS2 using epitaxially grown tungsten disulfide (WS2) on wrinkled graphene. Graphene wrinkles function as highly reactive nucleation sites on WS2 epilayers; however, they impede lateral growth and induce additional stress in the epilayer due to anisotropic friction. Moreover, partial dislocation‐driven in‐plane strain facilitates out‐of‐plane buckling with a height of 1 nm to release in‐plane strain. Remarkably, in‐plane strain relaxation at partial dislocations restores the bandgap to that of monolayer WS2 due to reduced interlayer interaction. These findings clarify significant substrate morphology effects even in vdW epitaxy and are potentially useful for various applications involving modifying optical and electronic properties by manipulating extended 1D defects via substrate morphology control. 相似文献
30.