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Ma Ji Chen Jinjin Chen Liye Zhou Xingjian Qin Xujia Tang Ying Sun Guodao Chen Jiazhou 《显形杂志》2021,24(3):545-563
Journal of Visualization - Effective extraction and visualization of complex target features from volume data are an important task, which allows the user to analyze and get insights of the complex... 相似文献
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中国剪纸的设计极具挑战性, 要求画面简洁、直观, 还需要表达特定的文化内涵, 且整张剪纸须整体连通。提出了一种基于图像的二维剪纸自动生成方法, 能够将任意数码照片自动转化为剪纸图形。首先,利用图像分割方法建立区域连接图; 接着, 基于该连接图对颜色、边界对比度和区域连通性进行数学建模, 并获得优化目标函数; 最后, 通过模拟退火算法求解目标方程, 自动生成保持图像内容的剪纸图形。还开发了连通性后处理和区域指定等用户交互工具, 允许用户在自动生成的剪纸图形中方便地加入个人设计。实验表明, 所生成的剪纸图形画面简洁、整体连通。 本方法在降低剪纸设计难度的同时还可满足个性化的设计需求, 有助于传播和传承我国的民间剪纸艺术。 相似文献
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Guanghui Feng Dr. Shibin Wang Prof. Shenggang Li Ruipeng Ge Dr. Xuefei Feng Prof. Junwei Zhang Dr. Yanfang Song Dr. Xiao Dong Jiazhou Zhang Prof. Gaofeng Zeng Prof. Qiang Zhang Prof. Guijun Ma Dr. Yi-De Chuang Prof. Xixiang Zhang Prof. Jinghua Guo Prof. Yuhan Sun Prof. Wei Wei Prof. Wei Chen 《Angewandte Chemie (International ed. in English)》2023,62(15):e202218664
Using sunlight to produce valuable chemicals and fuels from carbon dioxide (CO2), i.e., artificial photosynthesis (AP) is a promising strategy to achieve solar energy storage and a negative carbon cycle. However, selective synthesis of C2 compounds with a high CO2 conversion rate remains challenging for current AP technologies. We performed CO2 photoelectroreduction over a graphene/silicon carbide (SiC) catalyst under simulated solar irradiation with ethanol (C2H5OH) selectivity of>99 % and a CO2 conversion rate of up to 17.1 mmol gcat−1 h−1 with sustained performance. Experimental and theoretical investigations indicated an optimal interfacial layer to facilitate the transfer of photogenerated electrons from the SiC substrate to the few-layer graphene overlayer, which also favored an efficient CO2 to C2H5OH conversion pathway. 相似文献
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Shengqiang Nie Jiazhou Zeng Hui Qin Xiaolu Xu Jia Zeng Chunlin Yang Jun Luo 《先进技术聚合物》2019,30(4):923-931
In this study, we have provided a highly efficient, convenient, and universal protocol for preparing polyvinylidene fluoride (PVDF) membranes with low blood contact activation via in situ cross‐linking copolymerization of 2‐hydroxyethl methacrylate (HEMA) and acrylic acid (AA) in a solution of PVDF. The modified membranes were prepared from PVDF solution by phase inversion technology. The composition and morphology of the modified membranes were confirmed by attenuated total reflectance‐Fourier transform infrared (ATR‐FTIR) spectroscopy, thermogravimetric (TG) analysis, and scanning electron microscopy (SEM). Protein adsorption, clotting time, and contact activation on the modified PVDF membranes were systematically studied, the results indicating that after the incorporation of AA and HEMA, the modified PVDF membranes possessed anticoagulant properties in addition to low contact activation of blood components when in contact with blood. Therefore, fluorinated PVDF membranes with surfaces enriched with carboxyl and hydroxyl groups possessed the potential for use in long‐term blood‐contacting devices. 相似文献
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Uchinashi Y Nagasaki M Zhou J Tanaka K Fukase K 《Organic & biomolecular chemistry》2011,9(20):7243-7248
Despite the previous literature describing the "low-to-modest" efficiency, the readily available C5-acetamide donor was reinvestigated for its use in α-sialylation under microfluidic conditions. The N-phenyltrifluoroacetimidate donor was efficiently mixed with an appropriate amount of TMSOTf to produce the α(2-6) and α(2-3)-sialylation products of galactose and glucosamine acceptors in excellent yields and with nearly perfect α-selectivity. 相似文献
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Efficient Synthesis of the Disialylated Tetrasaccharide Motif in N‐Glycans through an Amide‐Protection Strategy 下载免费PDF全文
Dr. Jiazhou Zhou Dr. Yoshiyuki Manabe Dr. Katsunori Tanaka Prof. Koichi Fukase 《化学:亚洲杂志》2016,11(9):1436-1440
A disialylated tetrasaccharide, Neu5Ac(α2,3)Gal(β1,3)[Neu5Ac(α2,6)]GlcNAc ( 1 ), which is found at the termini of some N‐glycans, has been synthesized. Compound 1 was obtained through an α‐sialylation reaction between a sialic acid donor and a trisaccharide that was synthesized from the glycosylation of a sialylated disaccharide with a glucosaminyl donor. This synthetic route enabled the synthesis of the as‐described disialylated structure. A more‐convergent route based on the glycosylation of two sialylated disaccharides was also established to scale up the synthesis. Protection of the amide groups in the sialic acid residues significantly increased the yield of the glycosylation reaction between the two sialylated disaccharides, thus suggesting that the presence of hydrogen bonds on the sialic acid residues diminished their reactivity. 相似文献
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Sharma N Guo X Du G Guo Z Wang J Wang Z Peterson VK 《Journal of the American Chemical Society》2012,134(18):7867-7873
Lithium-ion batteries power many portable devices and in the future are likely to play a significant role in sustainable-energy systems for transportation and the electrical grid. LiFePO(4) is a candidate cathode material for second-generation lithium-ion batteries, bringing a high rate capability to this technology. LiFePO(4) functions as a cathode where delithiation occurs via either a solid-solution or a two-phase mechanism, the pathway taken being influenced by sample preparation and electrochemical conditions. The details of the delithiation pathway and the relationship between the two-phase and solid-solution reactions remain controversial. Here we report, using real-time in situ neutron powder diffraction, the simultaneous occurrence of solid-solution and two-phase reactions after deep discharge in nonequilibrium conditions. This work is an example of the experimental investigation of nonequilibrium states in a commercially available LiFePO(4) cathode and reveals the concurrent occurrence of and transition between the solid-solution and two-phase reactions. 相似文献
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We model a supply chain consisting of an author, a publisher, a physical bookstore (p-bookstore), and an electronic bookstore (e-bookstore). We employ game theory to examine and compare two types of pricing models of electronic books (e-books): wholesale model and agency model. Furthermore, we consider decentralized and horizontally centralized channels. The p-bookstore and e-bookstore are independent in the former but centralized in the latter. We adopt a simplified linear demand model to study when the publisher and the e-bookstore both benefit from the agency model. We find that a Pareto zone where both the publisher and e-bookstore benefit from the agency model always exists in the decentralized channels. In the agency model, the benefit from e-book sales may be more than the loss in physical book (p-book) sales. By contrast, a Pareto zone exists in the horizontally centralized channels if the wholesale price of p-books is not excessively low and the price elasticity is not extremely large. To check the robustness of our results, we relax model assumptions and conduct numerical studies in the Pareto zone to investigate how various parameters, such as authors royalty rate, affect profit improvement and readers welfare. We show that the publisher and bookstore have great potentials for profit improvement in the Pareto zone. Significant improvement is also observed in readers welfare. 相似文献
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