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261.
Journal of Inorganic and Organometallic Polymers and Materials - Starch based carbon nanotubes-iron oxide (CNT-IO) and carbon nanotubes-zirconium oxide (CNT-ZO) nanocomposites (NCs) were fabricated...  相似文献   
262.
The rat is one of the most commonly used animals in biological research and experimental investigations in medicine. The ultrafine structural components of the epithelium differ depending on the anatomy of the animal and the papilla type. Animal adaptation to food types and environmental circumstances may also be linked to morphological diversity. In the current study, seven male Wistar rat tongues were investigated. For scanning electron microscope (SEM), two rat tongues were immersed in a 10% formalin solution and the other two rat tongues were immersed in a 2.5% glutaraldehyde solution. The tongues of three rats were fixed for regular histological evaluation using triple staining. The three primary components of the Wistar rat tongue are the apex, body and root. The apex had a rounded and bifurcated shape. Filiform papillae and gustatory papillae were easily identified on the dorsal side of the tongue. There were three forms of gustatory papillae; fungiform papillae, vallate papillae and foliate papillae. The purpose of this study was to expose the tongue morphology of the Wistar rat species, which is widely used in investigations. Also, we wanted to show that formalin fixation can be utilized for morphological research in SEM. Finally, the Wistar rat tongue was thoroughly investigated and compared to those of other species.  相似文献   
263.
With recent Industry 4.0 developments, companies tend to automate their industries. Warehousing companies also take part in this trend. A shuttle-based storage and retrieval system (SBS/RS) is an automated storage and retrieval system technology experiencing recent drastic market growth. This technology is mostly utilized in large distribution centers processing mini-loads. With the recent increase in e-commerce practices, fast delivery requirements with low volume orders have increased. SBS/RS provides ultrahigh-speed load handling due to having an excess amount of shuttles in the system. However, not only the physical design of an automated warehousing technology but also the design of operational system policies would help with fast handling targets. In this work, in an effort to increase the performance of an SBS/RS, we apply a machine learning (ML) (i.e., Q-learning) approach on a newly proposed tier-to-tier SBS/RS design, redesigned from a traditional tier-captive SBS/RS. The novelty of this paper is twofold: First, we propose a novel SBS/RS design where shuttles can travel between tiers in the system; second, due to the complexity of operation of shuttles in that newly proposed design, we implement an ML-based algorithm for transaction selection in that system. The ML-based solution is compared with traditional scheduling approaches: first-in-first-out and shortest process time (i.e., travel) scheduling rules. The results indicate that in most cases, the Q-learning approach performs better than the two static scheduling approaches.  相似文献   
264.
The present work unveiled the distortion of oxygen octahedra influencing magnetic and magnetoelectric properties of novel Bi1−xErxFe1−yZryO3 (x = 0, .05, .1, y = .02, .05) polycrystalline nanoparticles by sol–gel route. X-ray diffraction patterns analysis reveals that pristine BiFeO3 and doped BiFeO3 are crystalized in the rhombohedral structure (R3c). The Fe–O–Fe bond angle of Bi1−xErxFe1−yZryO3 (x = 0, .05, .1, y = .02, .05) varies between 141° and 159.62° as the concentration of Er (via Bi site) and Zr (via Fe site) ions increases in BiFeO3. As a result, the tilt angle of oxygen octahedra and the canting angle of spiral spin arrangement increase. Hence, the maximum magnetization varies between .03144 and .37558 emu/g in Er and Zr co-doped BiFeO3 system. The number of electrons per unit cell of Bi1−xErxFe1−yZryO3 (x = 0, .05, .1, y = .02, .05) lies between 733.38 and 831, respectively. Further, the number of coherently diffracting domains increases from 3.07 to 5.21, and then it decreases when Er and Zr are increased in BiFeO3. Consequently, the magnetoelectric coupling coefficient varies between .0265 and .2511 mV/cm Oe, respectively. Particularly, Bi0.95Er0.05Fe0.98Zr0.02O3 shows enhanced magnetic and magnetoelectric behaviors compared to other samples.  相似文献   
265.
The effective thermal management of electronic system holds the key to maximize their performance. The recent miniaturization trends require a cooling system with high heat flux capacity, localized cooling, and active control. Nanomagnetic fluids (NMFs) based cooling systems have the ability to meet the current demand of the cooling system for the miniaturized electronic system. However, the thermal characteristics of NMFs have a long way to go before the internal mechanisms are well understood. This review mainly focuses on the three aspects to establish a correlation between the thermal and rheological properties of the NMFs. First, the background, stability, and factors affecting the properties of the NMFs are discussed. Second, the ferrohydrodynamic equations are introduced for the NMFs to explain the rheological behavior and relaxation mechanism. Finally, different theoretical and experimental models are summarized that explain the thermal characteristics of the NMFs. Thermal characteristics of the NMFs are significantly affected by the morphology and composition of the magnetic nanoparticles (MNPs) in NMFs as well as the type of carrier liquids and surface functionalization that also influences the rheological properties. Thus, understanding the correlation between the thermal characteristics of the NMFs and rheological properties helps develop cooling systems with improved performance.  相似文献   
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