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971.
首先介绍了噪声模拟实现的几种基本方法,然后给出了m序列的有关基本理论.在此基础上,提出了噪声实现的伪随机序列法.最后,利用DSP Builder实现了m序列的产生. 相似文献
972.
973.
Tae Hyun Park Hongkyu Eoh Youngdoo Jung Geon-Woo Lee Chang Eun Lee Han Sol Kang Junseok Lee Kwang-Bum Kim Du Yeol Ryu Seunggun Yu Cheolmin Park 《Advanced functional materials》2021,31(11):2008548
Flexible electronics that enable the visualization of thermal energy have significant potential for various applications, such as thermal diagnosis, sensing and imaging, and displays. Thermo-adaptive flexible electronic devices based on thin 1D block copolymer (BCP) photonic crystal (PC) films with self-assembled periodic nanostructures are presented. By employing a thermo-responsive polymer/non-volatile hygroscopic ionic liquid (IL) blend on a BCP film, full visible structural colors (SCs) are developed because of the temperature-dependent expansion and contraction of one BCP domain via IL injection and release, respectively, as a function of temperature. Reversible SC control of the bi-layered BCP/IL polymer blend film from room temperature to 80 °C facilitates the development of various thermo-adaptive SC flexible electronic devices including pixel arrays of reflective-mode displays and capacitive sensing display. A flexible diagnostic thermal patch is demonstrated with the bi-layered BCP/IL polymer blend enabling the visualization of local heat sources from the human body to microelectronic circuits. 相似文献
974.
Nan Song Zhijun Zhang Peiying Liu Dihua Dai Chao Chen Youmei Li Lei Wang Ting Han Ying-Wei Yang Dong Wang Ben Zhong Tang 《Advanced functional materials》2021,31(21):2009924
Supramolecular approaches have opened up vast possibilities to construct versatile materials, especially those with stimuli-responsiveness and integrated functionalities of multi-modal diagnosis and synergistic therapeutics. In this study, a hybrid theranostic nanosystem named TTPY-Py⊂CP5@AuNR is constructed via facile host–guest interactions, where TTPY-Py is a photosensitizer with aggregation-induced emission and CP5@AuNR represents the carboxylatopillar[5]arene (CP5)-modified Au nanorods. TTPY-Py⊂CP5@AuNR integrates the respective advantages of TTPY-Py and CP5@AuNR such as the high performance of reactive oxygen species generation and photothermal conversion, and meanwhile shows fluorescence responses to both temperature and pH stimuli. The successful modification of CP5 macrocycles on AuNRs surfaces can eliminate the cytotoxicity of AuNRs and enable them to serve as the nanocarrier of TTPY-Py for further theranostic applications. Significantly, in vitro and in vivo evaluations demonstrate that this supramolecular nanotheranostic system possesses multiple modalities including intensive fluorescence imaging (FLI), photoacoustic imaging (PAI), efficient photodynamic therapy (PDT), and photothermal therapy (PTT), indicating its great potential for FLI-PAI imaging-guided synergistic PDT-PTT therapy. Moreover, TTPY-Py can be released upon activation by the acidic environment of lysosomes and then specifically light up mitochondria. This study demonstrates a new strategy for the design of versatile nanotheranostics for accurate tumor imaging and cancer therapies. 相似文献
975.
Huanhuan Luo Li Kong Feng Zhang Chenglong Huang Jiayi Chen Hongbo Zhang Han Yu Song Zheng Hongwei Xu Yiran Zhang Lianfu Deng Gang Chen Hélder A. Santos Wenguo Cui 《Advanced functional materials》2021,31(27):2101262
Although great promise has been achieved with nanomedicines in cancer therapy, limitations are still encountered, such as short retention time in the tumor. Herein, a nanosystem that can modulate the particle size in situ by near-infrared (NIR) light is self-assembled by cross-linking the surface-modified poly(lactic-co-glycolic acid) from the up-conversion nanoparticle with indocyanine green and doxorubicin–nitrobenezene–polyethylene glycol (DOX–NB–PEG). The nanosystem with its small size (≈100 nm) achieves better tumor targeting, while the PEG on the surface of the nanosystem can effectively shield the adsorption of proteins during blood circulation, maintaining a stable nanostructure and achieving good tumor targeting. Moreover, the nanosystem at the tumor realizes the rapid shedding of PEG on its surface by NIR irradiation, and the enhanced cellular uptake. At the same time, aggregation occurs inside the nanosystem to form bigger particles (≈600 nm) in situ, prolonging the retention time at the tumor and producing enhanced targeted therapeutic effects. In vitro data show higher cellular uptake and a higher rate of apoptosis after irradiation, and the in vivo data prove that the nanosystem have a longer residence time at the tumor site after NIR irradiation. This nanosystem demonstrates an effective therapeutic strategy in targeted synergistic tumors. 相似文献
976.
Donghui Zhang Qi Chen Chao Shi Minzhang Chen Kaiqian Ma Jianglin Wan Runhui Liu 《Advanced functional materials》2021,31(6):2007226
Foreign-body response caused by implanted biomaterials seriously impedes the function of implants and is a major obstacle to the development of implantable biomaterials and medical devices. Recent advances in implantable biomaterials and medical devices have provided strategies to resist the foreign-body response. In this review, the mechanism of the foreign-body response and conventional strategies to mitigate foreign-body response is briefly introduced. Then, three types of promising foreign-body response resisting materials are focused and the advantages, characteristics, and applications of each material are discussed. Finally, prospects are put forward for future development of foreign-body response resisting materials and current challenges that require in-depth study. 相似文献
977.
3D Graphene Films Enable Simultaneously High Sensitivity and Large Stretchability for Strain Sensors 下载免费PDF全文
Fei Pan Si‐Ming Chen Yuhan Li Zhuchen Tao Jianglin Ye Kun Ni Han Yu Bin Xiang Yibin Ren Faxiang Qin Shu‐Hong Yu Yanwu Zhu 《Advanced functional materials》2018,28(40)
Integration of 2D membranes into 3D macroscopic structures is essential to overcome the intrinsically low stretchability of graphene for the applications in flexible and wearable electronics. Herein, the synthesis of 3D graphene films (3D‐GFs) using chemical vapor deposition (CVD) is reported, in which a porous copper foil (PCF) is chosen as a template in the atmospheric‐pressure CVD preparation. When the 3D‐GF prepared at 1000 °C (noted as 3D‐GF‐1000) is transferred onto a polydimethylsiloxane (PDMS) membrane, the obtained 3D‐GF‐1000/PDMS hybrid film shows an electrical conductivity of 11.6 S cm?1 with good flexibility, indicated by small relative resistance changes (ΔR/R0) of 2.67 and 0.36 under a tensile strain of 50% and a bending radius of 1.6 mm, respectively. When the CVD temperature is reduced to 900 °C (generating a sample noted as 3D‐GF‐900), the 3D‐GF‐900/PDMS hybrid film exhibits an excellent strain‐sensing performance with a workable strain range of up to 187% and simultaneously a gauge factor of up to ≈1500. The 3D‐GF‐900/PDMS also shows a remarkable durability in resistance in repeated 5000 stretching‐releasing cycles. Kinetics studies show that the response of ΔR/R0 upon strain is related to the graphitization and conductivity of 3D‐GF which are sensitive to the CVD preparation temperature. 相似文献
978.
979.
Xu-Qian Zheng Jaesung Lee Subrina Rafique Lu Han Christian A. Zorman Hongping Zhao Philip X.-L. Feng 《Journal of Electronic Materials》2018,47(2):973-981
Free-standing, very thin, single-crystal β-gallium oxide (β-Ga2O3) diaphragms have been constructed and their dynamical mechanical properties characterized by noncontact, noninvasive optical measurements harnessing the multimode nanomechanical resonances of these suspended nanostructures. We synthesized single-crystal β-Ga2O3 using low-pressure chemical vapor deposition (LPCVD) on a 3C-SiC epilayer grown on Si substrate at temperature of 950°C for 1.5 h. The synthesized single-crystal nanoflakes had widths of ~ 2 μm to 30 μm and thicknesses of ~ 20 nm to 140 nm, from which we fabricated free-standing circular drumhead β-Ga2O3 diaphragms with thicknesses of ~ 23 nm to 73 nm and diameters of ~ 3.2 μm and ~ 5.2 μm using a dry stamp-transfer technique. Based on measurements of multiple flexural-mode mechanical resonances using ultrasensitive laser interferometric detection and performing thermal annealing at 250°C for 1.5 h, we quantified the effects of annealing and adsorption of atmospheric gas molecules on the resonant characteristics of the diaphragms. Furthermore, we studied the effects of structural nonidealities on these free-standing β-Ga2O3 nanoscale diaphragms. We present extensive characterization of the mechanical and optical properties of free-standing β-Ga2O3 diaphragms, paving the way for realization of resonant transducers using such nanomechanical structures for use in applications including gas sensing and ultraviolet radiation detection. 相似文献
980.
Neugroschel A. Chih-Tang Sah Han K.M. Carroll M.S. Nishida T. Kavalieros J.T. Yi Lu 《Electron Devices, IEEE Transactions on》1995,42(9):1657-1662
A direct-current current-voltage (DCIV) measurement technique of interface and oxide traps on oxidized silicon is demonstrated. It uses the gate-controlled parasitic bipolar junction transistor of a metal-oxide-silicon field-effect transistor in a p/n junction isolation well to monitor the change of the oxide and interface trap density. The dc base and collector currents are the monitors, hence, this technique is more sensitive and reliable than the traditional ac methods for determination of fundamental kinetic rates and transistor degradation mechanisms, such as charge pumping 相似文献