排序方式: 共有33条查询结果,搜索用时 31 毫秒
11.
Yujian ZhangYanxian Jin Ru BaiZhenwei Yu Bin HuMi Ouyang Jingwei SunChunhui Yu Junlei LiuCheng Zhang 《Journal of photochemistry and photobiology. A, Chemistry》2012,227(1):59-64
Two blue-emitting oligomers, namely FDPA1 and FDPA2 containing 9,10-diphenylanthracene core end-capped with triphenylamine-substituted fluorene has been synthesized and characterized. The spiro-configuration end-capping groups imparts two compounds with pronounced morphological stability (Tg > 185 °C, Td > 420 °C) and excellent hole injection ability (EHOMO > −5.27 eV) with the advantageous optical characteristics of corresponding core. Scanning electron microscope (SEM) and X-ray diffraction (XRD) reveal that the two oligomers form excellent amorphous films and possess good morphological stability after annealing. 相似文献
12.
Dong Kaifeng Xu Kun Zhou Youyou Zuo Chao Wang Leimin Zhang Chuanke Jin Fang Song Junlei Mo Wenqin Hui Yajuan 《Nonlinear dynamics》2022,109(3):2129-2141
Nonlinear Dynamics - A new type of weak signal detection system that combines the memristor and Van der pol-Duffing chaotic system has been proposed in this paper, and the dynamic characteristics... 相似文献
13.
Acidizing technology has been widely applied when developing naturally fractured–vuggy reservoirs. So testing and evaluating acidizing wells’ pressure behavior become necessary for further improving the wells’ performance. Analyzing transient pressure data can estimate some key reservoir parameters. Generally speaking, carbonate minerals are usually composed of dolomite and calcite which are easy to be dissolved by hydrochloric acid which is often used to react with the rock to create a high conductivity channel, namely wormhole. Pressure transient behavior in fractured–vuggy reservoirs has been studied for many years; however, the models of acidizing wells with wormholes were not reported in previous studies. This article presented an analytical model for wormholes in naturally fractured–vuggy carbonate reservoirs, and wormholes solutions were obtained through point sink integral method. The results were validated accurately by comparing with previous results and numerical simulation. Then in this paper, type curves were established to recognize the flow characteristics, and flow was divided into six flow regimes comprehensively. The calculative results showed that the characteristics of type curves were influenced by inter-porosity flow factor, wormhole number, fluids capacitance coefficient. We also showed that the pressure behavior was affected by the angles between wormholes, and the pressure depletion increased as the angle decreased, because the wormholes were closer, their interaction became stronger. At the end, a reservoir example was showed to demonstrate the methodology of new type curve analysis. 相似文献
14.
通过三羟甲基氨基甲烷与BH3•THF反应制得1,3,2-噁唑硼烷络合物,并以其作为氢源,以甲磺酸铜为催化剂,在温和反应条件下(60 ℃, 24 h),实现了芳香醛的一锅法氢转移还原胺化,以45%~80%的收率得到20个二级胺类化合物,其结构经1H- NMR确证。 相似文献
15.
研究了2个拒绝可缓冲的同类机半在线排序问题. 设有2台同类机M1,M2,速度分别为1和s∈[1,+∞),加工不允许中断,工件Jj按照列表在线到达,每个工件带有2个参数:加工长度tj、拒绝罚值pj(模型1中)或拒绝获益pj(模型2中),当工件到达时,可以被接受并分给某台机器加工,也可以被拒绝,需付出一定的罚值(模型1)或取得一定的收益(模型2),目标是在第1个模型中要求极小化机器最大负荷和拒绝工件的总罚值之和;第2个模型中要求极大化机器最小负荷和总收益之和. 此外,在接受或拒绝的决策环节上提供一个缓冲区B,其容量为k≥1,任一时刻至多可以存放k个工件,当工件到达时,若缓冲区未饱和,则可暂时存入B;若已饱和,则必须在新工件和缓冲区内工件中选择一个进行接受或拒绝的决策. 本模型所研究的是经典可拒绝模型中的一个松弛问题,属半在线可拒绝模型.最后针对以上2个模型,分别给出了s在区间[1,+∞)上的近似算法,并证明了各自关于s的参数竞争比. 相似文献
16.
两台同型机M_1,M_2, 加工速度一致, 但拥有不同的加工能力,用其服务等级表示, M_1的服务等级为1, M_2的服务等级为2. 工件j按列表在线到达,每个工件带有三个参数: 长度t_j,等级g_j=1或2, 罚值p_j. 当j到达时, 可以被拒绝, 但要付出相应的罚值p_j, 也可以被接受并分配给服务等级不超过该工件等级的机器加工,事实上等级为1的工件只能分给M_1加工, 等级为2的工件可以分给M_1或M_2加工, 加工不允许中断. 目标为极小化加工工件集的最晚完工时间(makespan)和拒绝工件集的总罚值之和. 对于该问题给出了一个在线算法, 其竞争比为11/6, 以及问题一个下界5/3. 相似文献
17.
Alexander L. Antaris Dr. Junlei Chang Dr. Justin Z. Wu Bo Zhang Dr. Kai Cheng Prof. Calvin J. Kuo Prof. Hongjie Dai 《Angewandte Chemie (International ed. in English)》2015,54(49):14758-14762
Compared to imaging in the visible and near‐infrared regions below 900 nm, imaging in the second near‐infrared window (NIR‐II, 1000–1700 nm) is a promising method for deep‐tissue high‐resolution optical imaging in vivo mainly owing to the reduced scattering of photons traversing through biological tissues. Herein, semiconducting single‐walled carbon nanotubes with large diameters were used for in vivo fluorescence imaging in the long‐wavelength NIR region (1500–1700 nm, NIR‐IIb). With this imaging agent, 3–4 μm wide capillary blood vessels at a depth of about 3 mm could be resolved. Meanwhile, the blood‐flow speeds in multiple individual vessels could be mapped simultaneously. Furthermore, NIR‐IIb tumor imaging of a live mouse was explored. NIR‐IIb imaging can be generalized to a wide range of fluorophores emitting at up to 1700 nm for high‐performance in vivo optical imaging. 相似文献
18.
19.
Xueqin?Wang Junlei?Wang Zhaoliang?Ding Ningfang?Zhu Fang?Wang Kai?Cheng Qihui?Chen Hua?SongEmail author 《Russian Journal of Applied Chemistry》2018,91(5):764-769
The core-shell nanostructure materials have gained great interests because of its excellent photocatalytic properties and promising applications in several fields. In this work, we prepared the core-shell SiO2@TiO2 nanocomposites by the versatile kinetics-controlled coating method. The graphene oxide (GO) was further reduced over SiO2@TiO2 using UV-assisted photocatalytic reduction method. The physicochemical properties of the as-prepared SiO2@TiO2/RGO nanocomposites were characterized by SEM, XRD, BET, EDS, and FTIR. Results showed that, TiO2 was mainly composed of anatase phase with high crystallinity. Their photocatalytic activities were examined by the degradation of Rhodamine B (RhB) under UV light irradiation. The presence of RGO obviously improved the adsorption ability and photodegradation performance of the composites to RhB. The degradation kinetics of RhB can be described by the pseudo-first-order model. The optimum mass ratio of SiO2@TiO2 to RGO in the composite was 1/0.05 and the rate constant was about 4 times greater than that of the SiO2@TiO2. 相似文献
20.
Hui Wang Junlei Yang Penghui Cao Ning Guo Yuhao Li Yuefeng Zhao Shuang Zhou Ruizhuo Ouyang Yuqing Miao 《中国化学快报》2021,31(12):3015-3026
Multifunctional bismuth sulfide (Bi2S3) nanomaterials exhibit significant potential as nanomedicines for the diagnosis and treatment of cancer. These nanomaterials act as excellent photothermal agents and radiation sensitizers for the treatment of tumors, and they can also act as contrast agents for computed tomography (CT) imaging, photoacoustic imaging (PA), and other forms of imaging to provide real-time tumor monitoring and testing guidance. Compared with other nanomaterials, Bi2S3 nanomaterials can readily adapt to different applications by virtue of the fact that they can be easily functionalized. However, these nanomaterials have some limitations that cannot be ignored and need to be addressed, such as poor biocompatibility, toxicity, and low chemical stability. It is widely believed that appropriate functionalization of Bi2S3 nanomaterials could remedy such defects and significantly improve performance. This review summarizes the ways in which Bi2S3 nanomaterials can be functionalized and discusses their applications in cancer theranostics over the last few years, focusing particularly on imaging and therapy. We also discuss issues relating to how Bi2S3 nanomaterials can be analyzed, including how we might be able to use these systems to inhibit and treat tumors and how current limitations might be overcome to improve treatment efficacy. Finally, we hope to provide inspiration and guidance as to how we might create a more optimized multifunctional nano-system for the diagnosis and treatment of tumors. 相似文献