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21.
In confined space with length scale of several nanometers, the phase behavior of matter, e.g., nucleation and crystallization, is completely different from its analogue in bulk. However, in environmental applications, the relationship between the nanoconfined crystallization behavior of inorganic crystals and their properties for pollutant removal is rarely elucidated. Herein, an unusual formation of zirconium phosphate (ZrP) crystals as a mixture of both thermodynamically stable α‐ and metastable γ‐phases inside the nanoconfinement of 7.9 nm pores of mesoporous polystyrene (MPS) is reported. This consequently changes the interaction between ZrP and toxic metal cations from nonspecific electrostatic attraction of normal α‐ZrP to highly specific inner‐sphere coordination of nanoconfined γ‐ZrP, which exhibits remarkable reactivity as well as reusability for the removal of toxic metals. The results of this study contribute to a better understanding of the use of nanoconfinement for the regulation of material properties.  相似文献   
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Tissue regeneration in complex lesions such as the site of tumors, bacterial infection, and sites lacking blood vessels, has been a huge challenge. Therefore, developing bioactive implantable materials with multi-functional properties such as tumor destruction, bacteria growth inhibition, and angiogenesis promotion is of great significance. In this study, black CaO-SiO2-TiO2 (CST) glasses are prepared through the containerless melting approach, by which heterogeneous nucleation can be avoided and thereby glass formation becomes possible via fast quenching. This approach enables the formation of trivalent titanium (Ti3+) without using a reducing atmosphere or reducing agents. The black CST glasses are found in this study to possess a strong ability to inhibit bacteria and tumors by their excellent photothermal and photocatalytic effects. Strikingly, these glasses also promote the formation of blood vessels and accelerate the healing of chronic wounds by the synergistic effects of the photothermal effect and Si ions. Thus, this glass system can be a promising multi-functional material for tissue regeneration in complex lesions.  相似文献   
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Peripheral nerve injury is a common clinical problem bringing heavy burden to patients, due to its high incidence and unsatisfactory treatment. Nerve guidance conduit (NGC) is a promising scaffold for peripheral nerve repair, and bioactive agents are applied for great functional recovery. Melatonin (MLT) and Fe3O4 magnetic nanoparticles (Fe3O4‐MNPs) are proven to inhibit oxidative stress, inflammation, and induce nerve regeneration. Herein, a multilayered composite NGC loaded with MLT and Fe3O4‐MNPs is designed for sequential and sustainable drug release, creating an appropriate microenvironment for nerve regeneration. The composite scaffold shows sufficient mechanical strength and biocompatibility in vitro, and evidently promotes morphological, functional, and electrophysiological recovery of regenerated sciatic nerves in vivo. This work proves that the multilayered conduits show great prospect in the long‐term nerve defects treatment due to easy manufacture and desired efficacy.  相似文献   
26.
Mucogingival surgery has become a common procedure for soft gingival tissue reparation in dental clinical practice, which mainly relies on autograft or commercial collagen membranes (CM). However, the autograft faces grand challenges in source availability and long-term post-surgery pain management, and the CM is restricted by its poor mechanical properties in an aqueous environment. Here, it is reported that a bio-inspired lamellar chitosan scaffold (LCS) with long range ordered porous structure, manufactured through a bidirectional freezing method, can serve as a promising gingival tissue engineering material. The LCS not only exhibits excellent mechanical properties in the hydrated state but also accelerates vessel formation and soft tissue regeneration in vivo. Most interestingly, the LCS is found to be capable of inducing macrophage differentiation to M2 macrophages, which is thought to play an important role in tissue regeneration. These advantages combined with its easy and low-cost preparation process make the LCS a promising candidate for dental clinical applications.  相似文献   
27.
This paper presents a microelectronic system which is capable of making a signal record and functional electric stimulation of an injured spinal cord. As a requirement of implantable engineering for the regeneration microelectronic system, the system is of low noise, low power, small size and high performance. A front-end circuit and two high performance OPAs (operational amplifiers) have been designed for the system with different functions,and the two OPAs are a low-noise low-power two-stage OPA and a constant-g_m RTR input and output OPA. The system has been realized in CSMC 0.5-μm CMOS technology. The test results show that the system satisfies the demands of neuron signal regeneration.  相似文献   
28.
Tissue-engineered scaffolds have been extensively explored for treating bone defects; however, slow and insufficient vascularization throughout the scaffolds remains a key challenge for further application. Herein, a versatile microfluidic 3D printing strategy to fabricate black phosphorus (BP) incorporated fibrous scaffolds with photothermal responsive channels for improving vascularization and bone regeneration is proposed. The thermal channeled scaffolds display reversible shrinkage and swelling behavior controlled by near-infrared irradiation, which facilitates the penetration of suspended cells into the scaffold channels and promotes the prevascularization. Furthermore, the embedded BP nanosheets exhibit intrinsic properties for in situ biomineralization and improve in vitro cell proliferation and osteogenic differentiation. Following transplantation in vivo, these channels also promote host vessel infiltration deep into the scaffolds and effectively accelerate the healing process of bone defects. Thus, it is believed that these near-infrared responsive channeled scaffolds are promising candidates for tissue/vascular ingrowth in diverse tissue engineering applications.  相似文献   
29.
为了全光处理具有固定功率差异光信号,本文在详细分析非线性光纤环形镜(NOLM)受不同泵浦作用时输出特点的基础上,设计了将二元功率光信号进行幅度直接均衡的方案.利用光子学仿真软件进行了数值实验,结果显示二元信号经幅度均衡后的输出功率由均衡器输出级探测波功率直接确定,输出脉冲无波长改变,且幅度抖动小.输出脉冲无基座表明该方...  相似文献   
30.
PCB板酸性蚀刻机理、工艺参数及故障排除   总被引:1,自引:0,他引:1  
蚀刻工艺是目前PCB板制作中的重要工序之一,特别是随着微电子技术的飞速发展,大规模集成电路和超大规模集成电路的广泛应用,对PCB板制造技术提出了更高的要求,正向着高精度、高密度的方向飞速发展,对PCB板蚀刻的线宽公差也提出更高、更严的技术要求,所以,充分了解和掌握铜在各种类型蚀刻液中的蚀刻机理,并通过严格的科学实验,测定出铜在各类蚀刻液中工艺参数,才能把控好PCB板蚀刻这一关键工序。本文就我公司AS-301型酸性蚀刻液特点、蚀刻机理、来料检测、操作规程、工艺流程、故障排除等作简单介绍。  相似文献   
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