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排序方式: 共有463条查询结果,搜索用时 15 毫秒
61.
62.
M. M. Kamil S. A. Salem H. A. El‐Mansy B. M. Moustafa G. A. Ghazal 《Molecular nutrition & food research》2000,44(4):264-271
The morphological and chemical characteristics of ten varieties of sugar beet roots were evaluated during the season of 1996–1997. The best morphological characteristics were found in Top, Ito and Pamela varieties. The highest expected technological yield of sugar was found in Pamela and Top. The chemical constituents of different varieties of sugar‐beet roots showed significant differences. The suitability of sugar beet juice for preparing beet syrup as a new product was also evaluated and compared with sugar cane syrup. Purified beet‐syrups concentrated under vacuum or under atmospheric pressure showed more stability during storage than sugar cane syrup. The effect of storage conditions (at cold storage and at room temperature) and packaging materials (glass and polyethylene high‐density bottles) on properties of beet‐syrup and sugar cane syrup were also studied. 相似文献
63.
64.
abstract This study deals with the enhanced solubilization of polycyclic aromatic hydrocarbons (PAHs) such as phenan-threne (PHE) and fluorene (FLR) in a pure cationic gemini (G6) and three conventiona... 相似文献
65.
Hanna Lewandowska Andrzej Eljaszewicz Izabela Poplawska Marlena Tynecka Alicja Walewska Kamil Grubczak Jordan Holl Hady Razak Hady Slawomir Lech Czaban Joanna Reszec Grayna Przybytniak Wojciech Guszewski Jarosaw Sado Magorzata Dbrowska-Gralak Cezary Kowalewski Piotr Fiedor Tomasz Oldak Artur Kaminski Zbigniew Zimek Marcin Moniuszko 《International journal of molecular sciences》2021,22(16)
Gamma rays and electrons with kinetic energy up to 10 MeV are routinely used to sterilize biomaterials. To date, the effects of irradiation upon human acellular dermal matrices (hADMs) remain to be fully elucidated. The optimal irradiation dosage remains a critical parameter affecting the final product structure and, by extension, its therapeutic potential. ADM slides were prepared by various digestion methods. The influence of various doses of radiation sterilization using a high-energy electron beam on the structure of collagen, the formation of free radicals and immune responses to non-irradiated (native) and irradiated hADM was investigated. The study of the structure changes was carried out using the following methods: immunohistology, immunoblotting, and electron paramagnetic resonance (EPR) spectroscopy. It was shown that radiation sterilization did not change the architecture and three-dimensional structure of hADM; however, it significantly influenced the degradation of collagen fibers and induced the production of free radicals in a dose-dependent manner. More importantly, the observed effects did not disrupt the therapeutic potential of the new transplants. Therefore, radiation sterilization at a dose of 35kGy can ensure high sterility of the dressing while maintaining its therapeutic potential. 相似文献
66.
Masahiro Goto Seung-Zeon Han Kwangjun Euh Norio Kawagoishi Sangshik Kim Kusno Kamil 《Journal of Materials Science》2012,47(3):1497-1503
As possible substitutes for high-strength Cu–Be alloys, Cu–6Ni–2Mn–2Sn–2Al alloys have been developed. To clarify the physical
background of the effect of trace Zr on the fatigue strength of such alloys, the initiation and propagation behavior of a
major crack that led to the fracture of the tested specimens was monitored. When the stress amplitude was less than σ
a = 350 MPa, the fatigue life of the alloys with Zr was about 2–2.5 times larger than that of the alloy without Zr. When σ
a > 350 MPa, the effect of Zr addition on the fatigue life dramatically decreases as the stress amplitude increases. The increased
fatigue life due to Zr addition resulted from an enhancement of the crack initiation life and microcrack growth life. The
enhanced crack initiation life was mainly attributed to the strengthening of grain boundaries due to the precipitation of
SnZr compounds. A statistical analysis of the behavior of multiple cracks was made to quantitatively evaluate the scatter
in fatigue behavior. The statistical analysis supported the conclusions obtained from the behavior of a major crack. 相似文献
67.
多分类器组合能够在一定程度上弥补单个分类器的缺陷,因此它在模式识别中得到了广泛应用。深入调研国内外联机手写识别技术的研究动态,结合维吾尔文字母的独特书写风格,研究了基于多分类器集成的维吾尔语联机手写字母识别。利用5种不同的特征提取方法构造了5个独立的维吾尔语字母分类识别器,采用了等权投票和不等权投票等两种策略将5种维吾尔语字母分类识别器进行了有效组合。其中,单分类器采用了基于动态时间弯折(DTW)匹配距离的最近邻分类方法。实验结果表明,提出的集成策略的识别率明显高于单分类器的识别率,而且为特征的综合集成提供了多种有效途径。 相似文献
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69.
Kamil Zakwan Mohd Azmi Ahmad Shahrizan Abdul Ghani Zulkifli Md Yusof Zuwairie Ibrahim 《成像科学杂志》2013,61(6):330-342
ABSTRACTBlue–green colour cast effect and low contrast are common problems suffered by deep underwater images. This paper introduces a new method which consists of two major steps: red channel correction based on green and blue channels (RCCGB), and simultaneous contrast stretching and mean pixel enhancement (SCSMPE). The RCCGB is designed to minimize the effect of blue–green illumination. This step considers the differences between the red channel and other channels in terms of total pixel values. The second major step, SCSMPE is specifically designed to perform contrast stretching and improve the mean pixel value simultaneously through particle swarm optimization (PSO). Based on the visual observation, the proposed method significantly reduces the effect of the blue–green colour cast and improves the image contrast. Furthermore, the average quantitative values for 300 underwater images also demonstrate the superiority of the proposed method. 相似文献
70.
In this paper, we consider a practical problem, called Minimum Forwarding Set Problem (MFSP), that emerges within the context of implementing (energy efficient) communication protocols for wireless ad hoc or sensor networks. For a given node v, MFSP asks for a minimum cardinality subset of 1-hop neighbors of v to cover v’s 2-hop neighbors. MFSP problem is also known as multi-point relay (MPR) problem. It is shown to be an NP-complete problem for its general case that does not consider the coverage characteristics of wireless transmissions. In this paper, we present two polynomial time algorithms to solve the MFSP problem under disk coverage model for wireless transmissions. In our earlier work, we presented a polynomial time algorithm for this problem under unit disk coverage model. In the current work, we present several observations on the geometric characteristics of wireless transmissions under disk coverage model and build two alternative dynamic programming based solutions with different run time and space complexities to the problem. Disk coverage model is a more general model because it allows nodes to use arbitrary power levels for transmissions. As a result, the presented algorithms provide a more practical solution that can be used as a building block for energy efficient communication protocols designed for wireless ad hoc and sensor networks. 相似文献