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1.
GeTe is a promising candidate for the fabrication of high-temperature segments for p-type thermoelectric (TE) legs. The main restriction for the widespread use of this material in TE devices is high carrier concentration (up to ∼ 1021 cm−3), which causes the low Seebeck coefficient and high electronic component of thermal conductivity. In this work, the band structure diagram and phase equilibria data have been effectively used to attune the carrier concentration and to obtain the high TE performance. The Ge1−xBixTe (x = 0.04) material prepared by the Spark plasma sintering (SPS) technique demonstrates a high power factor accompanied by moderate thermal conductivity. As a result, a significantly higher dimensionless TE figure of merit ZT = 2.0 has been obtained at ∼ 800 K. Moreover, we are the first to propose that application of the developed Ge1−xBixTe (x = 0.04) material in the TE unicouple should be accompanied by SnTe and CoGe2 transition layers. Only such a unique solution for the TE unicouple makes it possible to prevent the negative effects of high contact resistance and chemical diffusion between the segments at high temperatures.  相似文献   
2.
Multimedia Tools and Applications - The three-dimensional models of brain tumors serve as diagnostic assistance for physicians, surgeons, and radiologists. The proposed system establishes an...  相似文献   
3.
Hydrogen production through water splitting is an efficient and green technology for fulfilling future energy demands. Carbon nanotubes (CNT) supported Ni2P has been synthesized through a simpler hydrothermal method. Ni2P/CNT has been employed as efficient electrocatalysts for hydrogen and oxygen evolution reactions in acidic and alkaline media respectively. The electrocatalyst has exhibited low overpotential of 137 and 360 mV for hydrogen and oxygen evolution reactions respectively at 10 mA cm?2. Lower Tafel slopes, improved electrochemical active surface area, enhanced stability have also been observed. Advantages of carbon support in terms of activity and stability have been described by comparing with unsupported electrocatalyst.  相似文献   
4.
Bulletin of Engineering Geology and the Environment - The pavements of the Beijing Capital International Airport (BCIA), China, where a buried fault zone lies beneath, have undergone continuous...  相似文献   
5.
Zinc (Zn), the second-most necessary trace element, is abundant in the human body. The human body lacks the capacity to store Zn; hence, the dietary intake of Zn is essential for various functions and metabolism. The uptake of Zn during its transport through the body is important for proper development of the three major accessory sex glands: the testis, epididymis, and prostate. It plays key roles in the initial stages of germ cell development and spermatogenesis, sperm cell development and maturation, ejaculation, liquefaction, the binding of spermatozoa and prostasomes, capacitation, and fertilization. The prostate releases more Zn into the seminal plasma during ejaculation, and it plays a significant role in sperm release and motility. During the maternal, labor, perinatal, and neonatal periods, the part of Zn is vital. The average dietary intake of Zn is in the range of 8–12 mg/day in developing countries during the maternal period. Globally, the dietary intake of Zn varies for pregnant and lactating mothers, but the average Zn intake is in the range of 9.6–11.2 mg/day. The absence of Zn and the consequences of this have been discussed using critical evidence. The events and functions of Zn related to successful fertilization have been summarized in detail. Briefly, our current review emphasizes the role of Zn at each stage of human reproduction, from the spermatogenesis process to childbirth. The role of Zn and its supplementation in in vitro fertilization (IVF) opens opportunities for future studies on reproductive biology.  相似文献   
6.
Heterogeneous sensor networks (HSN) find a wide range of applications in the field of military and civilian environments, where sensor nodes are utilized to estimate the position of a target with both dynamics and control input being unknown for the purposes of tracking. In the HSN, nodes are considered active depending upon their ability to sense the target output while the others are taken passive. Accurate estimation requires local information exchange among the spatially located sensor nodes, so that the active nodes as well as the passive nodes converge simultaneously to the same value. The local information exchange among the nodes is dictated by a connected graph. By using the criterion of collective observability, a novel distributed adaptive estimation scheme is introduced via adaptive observer where the nodes are allowed to have different sensor modalities. Using the estimated information, a subset of active and passive nodes, referred to as mobile nodes, can track the moving target. By using a constant state feedback controller at each mobile node, the state and parameter estimation as well as the tracking errors are shown to be uniformly ultimately bounded. Simulation results verify theoretical claims.  相似文献   
7.
Researchers have derived inspiration from the biophotosynthetic structures in nature and have started to synthesize the modified bioinspired solar cells copying the evolved organic and inorganic material properties. One of the highlighted examples of bioinspired photo voltaic (PV) cells is the astonishing achievement of an increase in the absorption of integrated sunlight waves in unpatterned solar cells simulated from the wings of the butterfly. Further, deployment possibilities of incorporating flexible cells on flat or curved surfaces for optimizing performance are also under progress. This article mainly discusses the recent concepts of bioinspired solar cells at the research and development level with the prospects and challenges that lie ahead in the upcoming field of photovoltaic renewable energy cell technology. Different potential materials found suitable for bioinspired solar cells construction are reviewed with their particular challenges.  相似文献   
8.
Journal of Materials Science - Flexible and stretchable strain sensors are in great demand in advanced health care, human–machine interface, stretchable electronics, electronic skin, etc. Of...  相似文献   
9.
Wireless Personal Communications - Ultrasound scan plays a predominant role in assisting the health care provider for monitoring pregnancy. This methods is employed for providing insights about...  相似文献   
10.
Bulletin of Engineering Geology and the Environment - The numerical methods for slope stability problems always have a serious concern related to their continuum and discontinuum nature. In...  相似文献   
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