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991.
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为了在非直达需求均能满足最少换乘的基础上进一步提高公交网络的直达率,建立了以直达率最大化和直达总时间最小化为目标的直达公交网络优化模型。与现有的研究相比,增加了换乘次数最小化约束,并采用具有遗传迭代机制的元启发式算法求解模型。利用Floyd算法求解初始网络最短路径,经线路删减、合并等操作后作为初始公交网络,使得模型具有高质量的初始解;通过space P法建模计算网络总换乘次数,在原有发车频率、最大车辆配备数、线路长度等约束下增加换乘次数最小化约束,采用频率共享规则进行客流分配,并与现有研究结果进行对比。结果表明,对于4条线路的Mandl's Swiss网络,在不考虑发车频率优化时,直达率较现有研究的试验1、2、3分别提高9.7%、8.41%和0.39%。 相似文献
993.
Dan Meng Wei Ma Xiaoling Wu Chuanlai Xu Hua Kuang 《Small (Weinheim an der Bergstrasse, Germany)》2020,16(23)
It is a significant challenge to achieve controllable self‐assembly of superstructures for biological applications in living cells. Here, a two‐layer core–satellite assembly is driven by a Y‐DNA, which is designed with three nucleotide chains that hybridized through complementary sequences. The two‐layer core–satellite nanostructure (C30S5S10 NS) is constructed using 30 nm gold nanoparticles (Au NPs) as the core, 5 nm Au NPs as the first satellite layer, and 10 nm Au NPs as the second satellite layer, resulting in a very strong circular dichroism (CD) and surface‐enhanced Raman scattering. After optimization, the yield is up to 85%, and produces a g‐factor of 0.16 × 10?2. The hybridization of the target microRNA (miRNA) with the molecular probe causes a significant drop in the CD and Raman signals, and this phenomenon is used to detect the miRNA in living cells. The CD signal has a good linear range of 0.011–20.94 amol ngRNA?1 and a limit of detection (LOD) of 0.0051 amol ngRNA?1, while Raman signal with the range of 0.052–34.98 amol ngRNA?1 and an LOD of 2.81 × 10?2 amol ngRNA?1. This innovative dual‐signal method can be used to quantify biomolecules in living cells, opening the way for ultrasensitive, highly accurate, and reliable diagnoses of clinical diseases. 相似文献
994.
Nan Zhang Kun Mei Ping Guan Xiaoling Hu Yanli Zhao 《Small (Weinheim an der Bergstrasse, Germany)》2020,16(23)
Proteins, like actors, play different roles in specific applications. In the past decade, significant achievements have been made in protein‐engineered biomedicine for cancer therapy. Certain proteins such as human serum albumin, working as carriers for drug/photosensitizer delivery, have entered clinical use due to their long half‐life, biocompatibility, biodegradability, and inherent nonimmunogenicity. Proteins with catalytic abilities are promising as adjuvant agents for other therapeutic modalities or as anticancer drugs themselves. These catalytic proteins are usually defined as enzymes with high biological activity and substrate specificity. However, clinical applications of these kinds of proteins remain rare due to protease‐induced denaturation and weak cellular permeability. Based on the characteristics of different proteins, tailor‐made protein‐based nanosystems could make up for their individual deficiencies. Therefore, elaborately designed protein‐based nanosystems, where proteins serve as drug carriers, adjuvant agents, or therapeutic drugs to make full use of their intrinsic advantages in cancer therapy, are reviewed. Up‐to‐date progress on research in the field of protein‐based nanomedicine is provided. 相似文献
995.
描述了目前B2B电子商务信息交换的需求,给出了将XML结合进B2B电子商务架构的优势,设计出了一种与XML集成的B2B电子商务架构,最后探讨了基于XML Web服务的动态电子商务的模型。 相似文献
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以正癸酸(CA)为相变材料,膨胀珍珠岩(EP)为基体材料,通过真空吸附法制备了可应用于外墙隔热控温领域的CA/EP定型复合相变材料。将CA/EP掺入水泥砂浆中制备了相变水泥板并测试其热特性,结果表明,CA/EP能提升水泥板的热能存储能力,20wt%相变水泥板的熔化、凝固相变潜热分别为14.25J·g-1、14.1J·g-1;CA/EP的加入能提高水泥板的比热容,且相变水泥板中复合相变材料含量越高,其等效比热容越大;定型复合相变材料CA/EP的加入能提高水泥板的比热容,且相变水泥板中复合相变材料含量越高,其等效比热容越大;CA/EP的加入会显著减小水泥板的导热系数和蓄热系数,增大热惰性系数。与普通水泥板相比,10wt%、15wt%、20wt%相变水泥板的导热系数分别下降了39.4%、47.83%和52.49%(20℃),37.94%、46.84%和50.63%(50℃),蓄热系数分别下降了34.07%、40.62%和44.87%(20℃),30.25%、35.59%和37.65%(50℃),热惰性系数分别增大8.75%、13.78%和15.96%(20℃),8.75%、21.53和26.21%(50℃)。 相似文献
999.
Chao Lian Xiaoling Xiao Zheng Chen Yuxi Liu Enyue Zhao Dingsheng Wang Chen Chen 《Nano Research》2016,9(2):435-441
Hexagonal ultrathin WO3 nano-ribbons (HUWNRs) of subnanometer thicknesses, 2–5 nm widths, and lengths of up to several micrometers were prepared by a solvothermal method. The as-prepared HUWNRs grow along the [001] direction, and the main exposed facet is the (120) crystal plane. The HUWNRs exhibit good electrochemical performance as an anode material in lithium ion batteries because of their unique structure. It is believed that these unique materials may be applied in many fields. 相似文献
1000.