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111.
Tellurium(Te) nanomaterials have aroused a wide interest in semiconductor, thermoelectric, piezoelectric, as well as biomedical applications. The last decades of reports indicated a major nanostructure of one-dimensional (1D) Te on account of its inherent structural anisotropy. Two-dimenional(2D) Te has been newly developed and drawn a lot of interests recently. This review presents the intrinsic biological potential of Te-based nanomaterials and summarizes their up-to-date advance in phototherapy and reactive oxygen species(ROS)-related applications in the biomedical field.  相似文献   
112.
With the advancement in tissue engineering, researchers are working hard on new techniques to fabricate more advanced scaffolds from biocompatible polymers with enhanced porosity, appropriate mechanical strength, diverse shapes and sizes for potential applications in biomedical field in general and tissue engineering in particular. These techniques include electrospinning, solution blow spinning, centrifugal spinning, particulate leaching (salt leaching), freeze-drying, lithography, self-assembly, phase separation, gas foaming, melt molding, 3-D printing, fiber mesh and solvent casting. In this article we have summarized the scaffold’s fabrication techniques from biocompatible polymers that are reported so far, the recent advances in these techniques, characterization of the physicochemical properties of scaffolds and their potential applications in the biomedical field and tissue engineering. The article will help both newcomers and experts working in the biomedical implant fabrication to not only find their desired information in one document but also understand the fabrication techniques and the parameters that control the success of biocompatible polymeric scaffolds. Furthermore, a static analysis of the work published in all forms on the most innovative techniques is also presented. The data is taken from Scopus, restricting the search to biomedical fields and tissue engineering.  相似文献   
113.
以美军CBU-94型断电弹药的战术应用为背景,探讨了其战术使用过程和作用原理.将导电纤维的落点分三个阶段进行计算,论述了子弹抛物线运动、纤维卷抛物线运动和导电纤维随风运动的计算方程,给出了以导电纤维落点为坐标原点,断电弹药投放时的坐标参数的计算方法,在已知目标点的GPS坐标的前提下,可以通过专门的三维坐标计算软件,计算出断电弹药投放时的GPS坐标.  相似文献   
114.
周慧  王中慧  晋卫军 《化学教育》2022,43(16):82-85
在处理电解质溶液的化学平衡理论中,有关离子的活度和活度系数的计算或估算都有比较严谨的理论公式或经验公式,而国内分析化学教材中关于经验公式的表述略显随意。以0.050 mol·L-1AlCl3水溶液中Cl-和Al3+的活度计算为例,结合国内外分析化学教材中关于活度系数计算的经验公式进行讨论。由计算结果可知,关于活度系数计算的经验公式需给出明确的使用条件。  相似文献   
115.
在时代发展过程中,广泛利用新能源技术,促进了智能建筑发展.近些年传感器精确度不断提高,产品也呈现出微型化和无线化发展,有利于实时监测建筑信息,利用物联网技术可以连接海量终端.科学技术不断发展,各行各业发展都需要利用互联网技术,大数据技术深刻影响到建筑行业,文章分析了大数据在智能建筑中的智慧应用,充分发挥出大数据技术的作...  相似文献   
116.
偏振探测的机理及应用   总被引:1,自引:1,他引:0  
偏振探测技术已经成为一种重要的探测手段。本文探讨了偏振探测的机理,如物体的表面特性(粗糙度、色泽和电导率等)对光的偏振特性的影响,介绍了偏振探测技术在地物遥感探测、大气探测、水下探测、医学诊断、天文探测、目标检测、图像处理和军事等领域的应用。  相似文献   
117.
膜进样质谱(MIMS)具有简单、快速和高灵敏等优点,在现场检测中的应用日益广泛。该技术利用半透膜将目标化合物从复杂的气相、液相体系中选择性分离后进入质谱进行分析检测。由于其可在不经色谱分离和样品前处理条件下实现复杂实际样品的分析,特别适合于现场应用。该文综述了膜进样质谱的原理和主要组成,重点论述了膜进样-单光子软电离质谱方面的技术进展以及膜进样质谱在环境、生态学、生命科学、生物等领域的应用进展。最后,对膜进样质谱今后的发展趋势进行了总结和展望。  相似文献   
118.
A variety of DNA-based probes are utilized for the detections of multiple analytes and DNA nanotechnology has been thriving for recent decades and achieving numerous nanostructures,mainly focusing on DNA morphology modulation and multifunctional systems engineered into to the complicated works.Among the numerous detections,fluorescence method is a non-invasive,highly selective and sensitive means for varieties of applications,but their emissions are often compromised by the aggregation-caused quenching(ACQ)effect,which weakens their applications.The aggregation induced emission luminogens(AIEgens)are created with non emissive or weakly emissive in a low concentration but emit strong fluorescence in a high concentration with aggregated states.Herein,numerous functionalized AIEgens have been emerged and used for detection and imaging and DNA-modified AIEgen probes are introduced.In this vein,here we report the progress on DNA-modified AIEgen probes in recent years and highlight their conjugation strategies including covalent bonding,electrostatic interaction and their applications of biosensing.Moreover,multiple DNA strands are needed to introduce into the DNA-modified AIEgen probes for more purposes.At the end,some challenges are mentioned to discuss the new trend of DNA-modified AIEgen probes.  相似文献   
119.
孙悦  龙彪 《移动通信》2021,(1):81-84
PFD管理方法主要用于解决后向数据相关规则传输过多时出现的负载过大问题,可动态推送PFD和相应计费规则.首先介绍了3GPP pre-R16中4G/5G的PFD管理方法,包括pull mode和push mode两种方法,同时分析了现有方法的不足,并介绍了相应的优化方案.应用新的优化方法,可减少PFDF和PCEF/TDF...  相似文献   
120.
Chia seeds (Salviae hispanicae semen) are obtained from Salvia hispanica L. This raw material is distinguished by its rich chemical composition and valuable nutritional properties. It is currently referred to as “health food”. The purpose of the present work was to perform a literature review on S. hispanica and chia seeds, focusing on their chemical composition, biological properties, dietary importance, and medicinal uses. The valuable biological properties of chia seeds are related to their rich chemical composition, with particularly high content of polyunsaturated fatty acids, essential amino acids, polyphenols, as well as vitamins and bioelements. The available scientific literature indicates the cardioprotective, hypotensive, antidiabetic, and antiatherosclerotic effects of this raw material. In addition, studies based on in vitro assays and animal and human models have proven that chia seeds are characterized by neuroprotective, hepatoprotective, anti-inflammatory, and antioxidant properties. These properties indicate a valuable role of chia in the prevention of civilization diseases. Chia seeds are increasingly popular in functional food and cosmetic and pharmaceutical industries. That is attributed not only to their desirable chemical composition and biological activity but also to their high availability. Nevertheless, S. hispanica is also the object of specific biotechnological studies aimed at elaboration of micropropagation protocols of this plant species.  相似文献   
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