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991.
求解一般车辆优化调度问题的一种改进遗传算法 总被引:4,自引:0,他引:4
文章在对一般车辆优化调度问题(VRP)进行分析的基础上,为之建立了数学模型;提出了一种求解该问题的改进遗传算法,并通过实例验证了该算法具有优良性能。 相似文献
992.
993.
综合利用扫描电镜能谱分析、X-射线衍射仪等先进仪器对SZ36-1油田滤膜组分燃烧前后进行综合分析研究。通过分析无机组分中Fe、Ca等元素的变化规律,并结合现场水质监测数据,研究发现SZ36-1油田回注污水由CEP向AJ、平台输送过程中水质逐级恶化;同时污水由CEP到A平台再到J平台过程中,Fe原子百分比平均值依次为4.45%、13.03%、19.45%,Ca原子百分比平均值依次为4.33%、5.43%、5.66%。腐蚀、结垢现象逐渐加剧,是导致注水水质恶化的主要原因。 相似文献
994.
995.
Plasma polymer coated surfaces for serum-free culture of limbal epithelium for ocular surface disease 总被引:2,自引:0,他引:2
Notara M Bullett NA Deshpande P Haddow DB MacNeil S Daniels JT 《Journal of materials science. Materials in medicine》2007,18(2):329-338
The potential use of plasma polymer coatings as substrates for serum-free expansion of limbal epithelial cells was investigated.
Preliminary studies using a human corneal epithelial cell line showed that acrylic acid-coated surfaces performed better than
allyl amine and allyl alcohol coated surfaces in terms of cell metabolic activity and confluence as assessed using the MTT
assay. Subsequently, the proliferation and maturity of primary human limbal epithelial cells in co-culture with growth arrested
3T3 fibroblasts on a range of acrylic acid plasma coated surfaces, octadiene plasma coated surfaces and tissue culture plastic
was investigated using MTT and cytokeratin 3 immunostaining. The cells performed better in the presence of serum on all surfaces.
However, the acrylic acid coated surfaces successfully sustained a serum-free fibroblast/epithelial cell co-culture. The metabolic
activity of the epithelial cells was superior on the acrylic acid coated surfaces than on tissue culture plastic in serum-free
conditions and their levels of differentiation were not significantly higher than in the presence of serum. These results
suggest that these surfaces can be used successfully for the serum-free expansion of human limbal epithelial cells. 相似文献
996.
Zeyu Jin Juan Lv Henglei Jia Weihong Liu Huanglong Li Zuhuang Chen Xi Lin Guoqiang Xie Xingjun Liu Shuhui Sun Hua‐Jun Qiu 《Small (Weinheim an der Bergstrasse, Germany)》2019,15(47)
Ir‐based binary and ternary alloys are effective catalysts for the electrochemical oxygen evolution reaction (OER) in acidic solutions. Nevertheless, decreasing the Ir content to less than 50 at% while maintaining or even enhancing the overall electrocatalytic activity and durability remains a grand challenge. Herein, by dealloying predesigned Al‐based precursor alloys, it is possible to controllably incorporate Ir with another four metal elements into one single nanostructured phase with merely ≈20 at% Ir. The obtained nanoporous quinary alloys, i.e., nanoporous high‐entropy alloys (np‐HEAs) provide infinite possibilities for tuning alloy's electronic properties and maximizing catalytic activities owing to the endless element combinations. Particularly, a record‐high OER activity is found for a quinary AlNiCoIrMo np‐HEA. Forming HEAs also greatly enhances the structural and catalytic durability regardless of the alloy compositions. With the advantages of low Ir loading and high activity, these np‐HEA catalysts are very promising and suitable for activity tailoring/maximization. 相似文献
997.
998.
Bemhard Blumenthal 《JOM Journal of the Minerals, Metals and Materials Society》1955,7(11):1199-1205
A melting process was developed by which high purity electrolytic uranium crystals can be converted into sound ingots without serious contamination. Careful preparation of the crystals, melting in a high vacuum, and directional solidification led to a metal of better than 99.993 wt pet purity. The metallographic examination showed a substantially clean metal with only residual amounts of a second phase which responded to heat treatment. The density of high purity uranium is 19.05 g per cu cm. 相似文献
999.
Hidetsugu Nanba Natsumi Anzen Manabu Okumura 《International Journal on Digital Libraries》2008,9(2):151-161
The need for academic researchers to retrieve patents and research papers is increasing, because applying for patents is now
considered an important research activity. However, retrieving patents using keywords is a laborious task for researchers,
because the terms used in patents for the purpose of enlarging the scope of the claims are generally more abstract than those
used in research papers. Therefore, we have constructed a framework that facilitates patent retrieval for researchers, and
have integrated research papers and patents by analysing the citation relationships between them. We obtained cited research
papers in patents using two steps: (1) detection of sentences containing bibliographic information, and (2) extraction of
bibliographic information from those sentences. To investigate the effectiveness of our method, we conducted two experiments.
In the experiment involving Step 1, we prepared 42,073 sentences, among which a human subject manually identified 1,476 sentences
containing citations of papers. For Step 2, we prepared 3,000 sentences, in which the titles, authors, and other bibliographic
information were manually identified. We obtained a precision of 91.6%, and a recall of 86.9% in Step 1, and a precision of
86.2% and a recall of 85.1% in Step 2. Finally, we constructed an information retrieval system that provided two methods of
retrieving research papers and patents. One method was retrieval by query, and another was from the citation relationships
between research papers and patents. 相似文献
1000.