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991.
Wei Han Zhao-Dong Wang Cheng-Zhi Xie Zhan-Quan Liu Shi-Ping Yan Dai-Zheng Liao Zong-Hui Jiang Peng Cheng 《Journal of chemical crystallography》2004,34(8):495-500
Two novel transition-metal copper and zinc complexes [(CuL)2]·(ClO4) (1) and [(ZnL)]·(ClO4)2 (2) (L = 1,4,7-tris(2-pyridylmethyl)-1,4,7-triazacyclononane) have been synthesized and structurally determined. The two complexes are both crystallized in monoclinic space group P2(1)/c with a = 14.318(4), b = 17.214(5), c = 22.403(7) Å, = 93.096(6)°, V = 5522(3) Å3, and Z = 4 for 1 and a = 9.371(2), b = 17.615(4), c = 17.579(4) Å, =104.070(4)°, V = 2814.6(11) Å3, and Z = 4 for 2. The center metal ions are coordinated to six nitrogen atoms, three of which are from triazacyclononane and other three from the pendant-arms 2-pyridylmethyl, forming a slightly distorted octahedral geometry. Two complexes have been characterized by element analysis, infrared spectroscopy, and the UV–Vis and ESR spectra for 1 have also been determined. 相似文献
992.
Stimuli‐Responsive Nucleic Acid‐Based Polyacrylamide Hydrogel‐Coated Metal–Organic Framework Nanoparticles for Controlled Drug Release
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Wei‐Hai Chen Wei‐Ching Liao Yang Sung Sohn Michael Fadeev Alessandro Cecconello Rachel Nechushtai Itamar Willner 《Advanced functional materials》2018,28(8)
The synthesis of doxorubicin‐loaded metal–organic framework nanoparticles (NMOFs) coated with a stimuli‐responsive nucleic acid‐based polyacrylamide hydrogel is described. The formation of the hydrogel is stimulated by the crosslinking of two polyacrylamide chains, PA and PB, that are functionalized with two nucleic acid hairpins ( 4 ) and ( 5 ) using the strand‐induced hybridization chain reaction. The resulting duplex‐bridged polyacrylamide hydrogel includes the anti‐ATP (adenosine triphosphate) aptamer sequence in a caged configuration. The drug encapsulated in the NMOFs is locked by the hydrogel coating. In the presence of ATP that is overexpressed in cancer cells, the hydrogel coating is degraded via the formation of the ATP–aptamer complex, resulting in the release of doxorubicin drug. In addition to the introduction of a general means to synthesize drug‐loaded stimuli‐responsive nucleic acid‐based polyacrylamide hydrogel‐coated NMOFs hybrids, the functionalized NMOFs resolve significant limitations associated with the recently reported nucleic acid‐gated drug‐loaded NMOFs. The study reveals substantially higher loading of the drug in the hydrogel‐coated NMOFs as compared to the nucleic acid‐gated NMOFs and overcomes the nonspecific leakage of the drug observed with the nucleic‐acid‐protected NMOFs. The doxorubicin‐loaded, ATP‐responsive, hydrogel‐coated NMOFs reveal selective and effective cytotoxicity toward MDA‐MB‐231 breast cancer cells, as compared to normal MCF‐10A epithelial breast cells. 相似文献
993.
Graphene Oxide‐Template Controlled Cuboid‐Shaped High‐Capacity VS4 Nanoparticles as Anode for Sodium‐Ion Batteries
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Sizhe Wang Feng Gong Shize Yang Jiaxuan Liao Mengqiang Wu Ziqiang Xu Cheng Chen Xiaofei Yang Feipeng Zhao Bin Wang Yuesheng Wang Xueliang Sun 《Advanced functional materials》2018,28(34)
Room‐temperature sodium‐ion batteries have attracted great attentions for large‐scale energy storage applications in renewable energy. However, exploring suitable anode materials with high reversible capacity and cyclic stability is still a challenge. The VS4, with parallel quasi‐1D chains structure of V4+(S22?)2, which provides large interchain distance of 5.83 Å and high capacity, has showed great potential for sodium storage. Here, the uniform cuboid‐shaped VS4 nanoparticles are prepared as anode for sodium‐ion batteries by the controllable of graphene oxide (GO)‐template contents. It exhibits superb electrochemical performances of high‐specific charge capacity (≈580 mAh·g?1 at 0.1 A·g?1), long‐cycle‐life (≈98% retain at 0.5 A·g?1 after 300 cycles), and high rates (up to 20 A·g?1). In addition, electrolytes are optimized to understand the sodium storage mechanism. It is thus demonstrated that the findings have great potentials for the applications in high‐performance sodium‐ion batteries. 相似文献
994.
Yan Huang Guisheng Liao Jun Li Jie Li Hai Wang 《Multidimensional Systems and Signal Processing》2017,28(4):1183-1202
Based on the sum and difference coarrays, multiple-input multiple-output (MIMO) radar with minimum redundancy (MR) concept, referred to as MR MIMO, can considerably increase the spatial degrees of freedom (DOFs). However, traditional MR MIMO needs computational search to determine the position of each element. In this paper, a modified MR monostatic MIMO configuration is proposed, referred to as MMRM MIMO. In the proposed system, the MMRM MIMO radar is consisted of several levels of uniform linear array, which brings the advantage that the position of each element can be determined without computational search. Furthermore, it offers more than \(N^{2}\) DOFs for an N-elemental array. In order to utilize the extended DOFs of MMRM MIMO radar for direction-of-arrival (DOA) estimation, an average Toeplitz approximation method (TAM) is employed, which achieves robust performance even under low signal-to-noise ratio, few snapshots and array error. Numerous simulation results are provided to demonstrate the effectiveness of the proposed method for DOA estimation. 相似文献
995.
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997.
针对高职院校现有的计算机实训室中,计算机实训机房管理中的资源分配复杂、利用不高、运维成本高等问题,采取基于校园私有云的方式来构建实训教学环境,使得实训教学环境高可用、自动交付.最后通过效果分析,验证所构建的环境平台是可行和有效的. 相似文献
998.
用现有的红外法测量的GaN基HEMT器件结温,比实际最高温度点的温度低.而用喇曼法测量结温对设备要求高且不易于操作.针对现有技术对GaN基HEMT器件结温的测量存在一定困难的问题,设计了一款HEMT器件匹配电路.利用红外热像仪测量HEMT器件的结温升高,并结合物理数值模拟仿真,提出一种小尺寸栅极结温升高测量方法.结果表明,建立正确的仿真模型,可以得到不同栅极长度范围内的温度.通过这种方法可以测量出更接近实际的结温,为之后研究加载功率与壳温对AlGaN/GaN HEMT器件热阻的影响奠定了理论基础,并且为实际工作中热特性研究提供了参考依据. 相似文献
999.
Solution‐Processed Extremely Efficient Multicolor Perovskite Light‐Emitting Diodes Utilizing Doped Electron Transport Layer
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Khan Qasim Baoping Wang Yupeng Zhang Pengfei Li Yusheng Wang Shaojuan Li Shuit‐Tong Lee Liang‐Sheng Liao Wei Lei Qiaoliang Bao 《Advanced functional materials》2017,27(21)
A specially designed n‐type semiconductor consisting of Ca‐doped ZnO (CZO) nanoparticles is used as the electron transport layer (ETL) in high‐performance multicolor perovskite light‐emitting diodes (PeLEDs) fabricated using an all‐solution process. The band structure of the ZnO is tailored via Ca doping to create a cascade of conduction energy levels from the cathode to the perovskite. This energy band alignment significantly enhances conductivity and carrier mobility in the CZO ETL and enables controlled electron injection, giving rise to sub‐bandgap turn‐on voltages of 1.65 V for red emission, 1.8 V for yellow, and 2.2 V for green. The devices exhibit significantly improved luminance yields and external quantum efficiencies of, respectively, 19 cd A?1 and 5.8% for red emission, 16 cd A?1 and 4.2% for yellow, and 21 cd A?1 and 6.2% for green. The power efficiencies of these multicolor devices demonstrated in this study, 30 lm W?1 for green light‐emitting PeLED, 28 lm W?1 for yellow, and 36 lm W?1 for red are the highest to date reported. In addition, the perovskite layers are fabricated using a two‐step hot‐casting technique that affords highly continuous (>95% coverage) and pinhole‐free thin films. By virtue of the efficiency of the ETL and the uniformity of the perovskite film, high brightnesses of 10 100, 4200, and 16,060 cd m?2 are demonstrated for red, yellow, and green PeLEDs, respectively. The strategy of using a tunable ETL in combination with a solution process pushes perovskite‐based materials a step closer to practical application in multicolor light‐emitting devices. 相似文献
1000.
Wearable,Healable, and Adhesive Epidermal Sensors Assembled from Mussel‐Inspired Conductive Hybrid Hydrogel Framework
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Meihong Liao Pengbo Wan Jiangru Wen Min Gong Xiaoxuan Wu Yonggang Wang Rui Shi Liqun Zhang 《Advanced functional materials》2017,27(48)
Healable, adhesive, wearable, and soft human‐motion sensors for ultrasensitive human–machine interaction and healthcare monitoring are successfully assembled from conductive and human‐friendly hybrid hydrogels with reliable self‐healing capability and robust self‐adhesiveness. The conductive, healable, and self‐adhesive hybrid network hydrogels are prepared from the delicate conformal coating of conductive functionalized single‐wall carbon nanotube (FSWCNT) networks by dynamic supramolecular cross‐linking among FSWCNT, biocompatible polyvinyl alcohol, and polydopamine. They exhibit fast self‐healing ability (within 2 s), high self‐healing efficiency (99%), and robust adhesiveness, and can be assembled as healable, adhesive, and soft human‐motion sensors with tunable conducting channels of pores for ions and framework for electrons for real time and accurate detection of both large‐scale and tiny human activities (including bending and relaxing of fingers, walking, chewing, and pulse). Furthermore, the soft human‐motion sensors can be enabled to wirelessly monitor the human activities by coupling to a wireless transmitter. Additionally, the in vitro cytotoxicity results suggest that the hydrogels show no cytotoxicity and can facilitate cell attachment and proliferation. Thus, the healable, adhesive, wearable, and soft human‐motion sensors have promising potential in various wearable, wireless, and soft electronics for human–machine interfaces, human activity monitoring, personal healthcare diagnosis, and therapy. 相似文献