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排序方式: 共有416条查询结果,搜索用时 15 毫秒
1.
Metin Kul Muhsin Zor Ahmet Senol Aybek Sinan Irmak Evren Turan 《Solar Energy Materials & Solar Cells》2007,91(10):882-887
The CdO:F samples have been deposited onto microscope glass substrates at 250 °C by ultrasonic spray pyrolysis method. With the incorporation of fluorine into CdO, the direct optical transition has shifted towards the shorter wavelengths, and the transparency of the material has increased at a given wavelength above the fundamental absorption edge. The shift in the absorption edge is explained by means of the Moss–Burstein effect, which is also supported with the results of the current–voltage characteristics. Here, a correlation has been established between the band broadening and the increase in conductivity due to the increase in carrier density. 相似文献
2.
A method for the time suboptimal control of an industrial manipulator from an initial position and orientation to a final
position and orientation as it moves along a specified path is proposed. Nonlinear system equations that describe the manipulator
motion are linearized at each time step along the path. A method which gives the control inputs (joint angular velocities)
for time suboptimal control of the manipulator is developed. In the formulation, joint angular velocity and acceleration limitations
are also taken into consideration. A six degree of freedom elbow type manipulator is used in numerical examples to verify
the method developed. 相似文献
3.
Cemile 《中国化学工程学报》2021,37(9):121-127
In this study,a sequential process (heterotrophic up-flow column and completely mixed membrane bioreactors) was proposed combining advantages of the both processes.The system was operated for 249 days with simulated and real groundwater for nitrate removal at concentrations varying from 25 to 145 mg·L-1 NO3-N.The contribution of heterotrophic process to total nitrate removal in the system was controlled by dozing the ethanol considering the nitrate concentration.By this way,sulfur based autotrophic denitrification rate was decreased and the effluent sulfate concentrations were controlled.The alkalinity requirement in the autotrophic process was produced in the heterotrophic reactor,and the system was operated without alkalinity supplementation.Throughout the study,the chemical oxygen demand in the heterotrophic reactor effluent was (23.7 ± 22) mg·L-1 and it was further decreased to(7.5 ± 7.2) mg·L-1 in the system effluent,corresponding to a 70% reduction.In the last period of the study,the real groundwater containing 145 mg·L-1 NO3-N was completely removed.Membrane was operated without chemical washing in the first 114 days.Between days 115-249 weekly chemical washing was required. 相似文献
4.
5.
金属有机框架(MOFs)材料因其大的比表面积、可调控的孔道结构和丰富的活性位点引起了国内外学者们的广泛关注。近年来MOFs基材料广泛应用于能量储存与转化领域,但大多数MOFs基材料的低稳定性和低导电性等缺陷限制了其实际应用。通过对MOFs基材料进行改性,如采用共轭度高的有机配体以增加MOFs材料的稳定性,或MOFs衍生物以提高其氧化还原活性位点和导电性,从而达到提高MOFs基电极材料的电化学性能。主要介绍了原始MOFs及其衍生材料如碳材料、金属氧化物、金属硫化物、金属氢氧化物和金属磷化物等在超级电容器电极材料中的最新研究进展。研究表明,多金属MOFs材料或多金属MOFs衍生物有利于提高电极材料的电化学性能,而导电MOFs材料或MOFs衍生物中的碳材料有利于提高电极材料的导电性。最后对MOFs基电极材料在电化学储能领域中的研究做出了展望,指出MOFs基材料的形貌、组分和导电性是未来研究的发展方向。 相似文献
6.
Sinan Zhang Yadonga Zhao Xueshuang Yao Zhenhong Zheng Chuyao Zheng Zhuo Jiang 《International Journal of Food Science & Technology》2022,57(7):4245-4253
Ripe carambolas are hard to store and transport, while freeze-dried ones are easy to store. However, its long production time leads to higher costs. This study shows that high hydrostatic pressure (HHP) treatment could shorten the freeze-drying time of carambola slices. After HHP treatment (25–250 MPa), the drying time of the fresh sample can be shortened by 33.3–44.4% and the distribution of water and pigment in tissues is much uniform. With the increment of the pressure, 2,2-diphenyl-1-picrylhydrazyl (DPPH) and hydroxyl radical scavenging rate are increased. At 250 MPa, the total phenolic content (TPC) increased from 11.34 to 13.36 mg GAE g−1, and the total flavonoid content (TFC) of the control sample was increased from 10.77 to 12.73 mg RE g−1. Compared with the untreated sample, HHP treatment can enhance the flavour and shorten the freeze-drying time. This work guides the application of HHP technology for drying food processing. 相似文献
7.
Iris Ribitsch Andrea Bileck Alexander D. Aldoshin Maciej M. Kadua Rupert L. Mayer Monika Egerbacher Simone Gabner Ulrike Auer Sinan Gültekin Johann Huber David P. Kreil Christopher Gerner Florien Jenner 《International journal of molecular sciences》2021,22(11)
Tendinopathies are painful, disabling conditions that afflict 25% of the adult human population. Filling an unmet need for realistic large-animal models, we here present an ovine model of tendon injury for the comparative study of adult scarring repair and fetal regeneration. Complete regeneration of the fetal tendon within 28 days is demonstrated, while adult tendon defects remained macroscopically and histologically evident five months post-injury. In addition to a comprehensive histological assessment, proteome analyses of secretomes were performed. Confirming histological data, a specific and pronounced inflammation accompanied by activation of neutrophils in adult tendon defects was observed, corroborated by the significant up-regulation of pro-inflammatory factors, neutrophil attracting chemokines, the release of potentially tissue-damaging antimicrobial and extracellular matrix-degrading enzymes, and a response to oxidative stress. In contrast, secreted proteins of injured fetal tendons included proteins initiating the resolution of inflammation or promoting functional extracellular matrix production. These results demonstrate the power and relevance of our novel ovine fetal tendon regeneration model, which thus promises to accelerate research in the field. First insights from the model already support our molecular understanding of successful fetal tendon healing processes and may guide improved therapeutic strategies. 相似文献
8.
选取3种不同密度的WC-17Co粉末,采用超音速火焰喷涂法制备厚度为0.3 mm的涂层。通过扫描电镜观察分析了3种涂层的孔隙率,采用压痕法测量了涂层的努氏硬度与弹性模量,同时采用剥层法对不同密度粉末制备的WC-17Co涂层残余应力进行了测试与计算。结果表明,涂层孔隙率随WC-17Co粉末密度的增大而增大,涂层的努氏硬度、弹性模量均随WC-17Co粉末密度的增大而减小。WC-17Co涂层内部存在的残余应力表现为压应力,且应力值随涂层厚度的增大而增加,在临近涂层-基体界面处迅速减小。涂层残余压应力最大值随WC-17Co粉末密度的增大而增加:粉末密度为11.52、12.86、13.49 g·cm-3所制备的涂层残余应力最大值分别为-798、 -986和-1120 MPa。 相似文献
9.
Junjie Wang Shangshu Wu Shu Fu Sinan Liu Zhiqiang Ren Mengyang Yan Shuangqin Chen Si Lan Horst Hahn Tao Feng 《材料科学技术学报》2021,77(18):126-130
A nanocrystalline CoCrFeNiMn high-entropy alloy(nc-HEA)with nano-multiphase structure was pre-pared by inert gas condensation(IGC)using a laser evaporation source.Encouragingly,the laser-IGC nc-HEA exhibits unexpected ferromagnetic behavior and the Curie temperature(Tc)increased nearly 10 times compared to any CoCrFeNiMn HEAs prepared by various other methods.In addition,the saturation magnetization(Ms)and Tc of the laser-IGC nc-HEA can be controlled via heat treatment,which is result-ing from the formation and structural evolution of magnetic nanophases during annealing.This work widens the design toolbox for high-performance nc-HEAs based upon laser-IGC technique. 相似文献
10.
Sinem Palantken Emre Tekay Sinan en Turgut Nugay Nihan Nugay 《Polymer Composites》2016,37(9):2770-2781
A novel method based on cryoscopic expansion of halloysite nanotubes via frozen water molecules entrapped in their lumens and subsequent lyophilization was described. Detailed analyses confirmed that the inner and outer diameters as well as the surface area of the nanotubes could be efficiently increased without disturbing the inherent tubular structure. The benefits of cryo‐expanded nanotubes for the enhancement of chitosan hydrogel performances were discussed. The composite hydrogels, depending on their compositions and morphologies, exhibited significantly enhanced swelling and mechanical properties compared with neat chitosan hydrogel. This effect was even more pronounced in the hydrogels containing cryo‐expanded halloysite nanotubes. Although neat chitosan is a selectively good adsorbent for anionic dyes, in the presence of a small amount of cryo‐expanded halloysite, the resultant composite hydrogel can establish a relatively high adsorption capacity for anionic and cationic dyes as a broad‐spectrum dye adsorbent. POLYM. COMPOS., 37:2770–2781, 2016. © 2015 Society of Plastics Engineers 相似文献