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31.
Based on the crystal structures of human α‐GalCer–CD1d and iNKT–α‐GalCer–CD1d complexes, nonglycosidic analogues of α‐GalCer were synthesized. They activate iNKT cells resulting in dendritic cell maturation and the priming of antigen‐specific T and B cells. Therefore, they are attractive adjuvants in vaccination strategies for cancer and infectious diseases.

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32.
In this work, lanthanum phosphate with a 20% yttria (LaPO4/Y2O3) composite prepared by an Aqueous Sol–Gel process is machined using an Abrasive Water Jet Machine (AWJM). The machinability of this composite is studied by varying the input parameters namely Jet Pressure (JP), Stand-Off Distance (SOD), and Traverse Speed (TS) on Surface finish. Garnet of 80 mesh size is used as an abrasive with a flow rate of 85?g/min. The microstructural characterization study reveals the presence of new element YPO4. This element enhances the machinability and reduced porosity in the composite. Microscopy examinations on the machined surface reveals that partial overlapping at low JP, poor surface finish at high JP and SOD, forged deficiency at maximum SOD and TS. The minimum levels of all input parameters are influenced to obtain acceptable Ra. Atomic Force Microscopy (AFM) on the kerf surface shows micro wear track and peaks. The Multiple Regression Analysis (MRA) is developed for Ra to check the adequacy. From the Analysis of Variance (ANOVA), SOD has a significant effect on Ra with a contribution of 53%. The influence of JP and TS on Ra is found to be 31% and 15%, respectively.  相似文献   
33.
Multimedia Tools and Applications - True Random Number Generator (TRNG) has become a central element of today’s secure communication. TRNGs developed through FPGA implementation have a...  相似文献   
34.
Highly flexible supercapacitors (SCs) have great potential in modern electronics such as wearable and portable devices. However, ultralow specific capacity and low operating potential window limit their practical applications. Herein, a new strategy for the fabrication of free‐standing Ni?Mo?S and Ni?Fe?S nanosheets (NSs) for high‐performance flexible asymmetric SC (ASC) through hydrothermal and subsequent sulfurization technique is reported. The effect of Ni2+ is optimized to attain hierarchical Ni?Mo?S and Ni?Fe?S NS architectures with high electrical conductivity, large surface area, and exclusive porous networks. Electrochemical properties of Ni?Mo?S and Ni?Fe?S NS electrodes exhibit that both have ultrahigh specific capacities (≈312 and 246 mAh g?1 at 1 mA cm?2), exceptional rate capabilities (78.85% and 78.46% capacity retention even at 50 mA cm?2, respectively), and superior cycling stabilities. Most importantly, a flexible Ni?Mo?S NS//Ni?Fe?S NS ASC delivers a high volumetric capacity of ≈1.9 mAh cm?3, excellent energy density of ≈82.13 Wh kg?1 at 0.561 kW kg?1, exceptional power density (≈13.103 kW kg?1 at 61.51 Wh kg?1) and an outstanding cycling stability, retaining ≈95.86% of initial capacity after 10 000 cycles. This study emphasizes the potential importance of compositional tunability of the NS architecture as a novel strategy for enhancing the charge storage properties of active electrodes.  相似文献   
35.
Journal of Materials Science - To develop advanced anode materials for Li-ion batteries (LIB), an extensive research effort is being employed. The effort focuses much on silicon-based anodes due to...  相似文献   
36.
Journal of Materials Science: Materials in Electronics - Zinc Oxide/Nickel Oxide (ZnO/NiO) heterostructures were deposited using the spray pyrolysis technique by varying NiO content. The X-ray...  相似文献   
37.

The recent advancements in the internet technology have created the urgency in developing critical data security framework around the globe. One of the most shared multimedia objects is the image which is safeguarded through a task called image encryption. An integrated approach to image encryption is the need of the hour which can combine algorithm and communication model. In this context, this work presents the first- of- its- kind approach addressing Elliptic Curve Cryptography (ECC) to encrypt and decrypt the images to enhance their security during transmission via Single Carrier Frequency Division Multiple Access (SC-FDMA) communication systems. The uniqueness of this work is to combine the encryption scheme and subsequent wireless transmission. Modified Huffman coding has been employed to achieve compression. The viability of the proposed approach was tested and the performance metrics namely Entropy, PSNR, Histogram, correlation coefficient, differential attack, NIST test, and occulation attack analyses were evaluated. The simulation results prove the efficiency of the proposed integrated encryption – compression – communication schema.

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38.

The recent communication receiver requires compact size, low cost, less weight and high-performance antenna for broadband applications. This paper compares the performance of the microstrip patch antenna designed using h-BN nano ceramic substrate with antenna designed using FR4 substrate. In this proposed new substrate is developed using powder metallurgy principle. Simulated and experimental results shows that proposed substrate for patch antenna in S-band applications achieve good resonance at two different frequencies 2.2 and 2.6 GHz with reflection coefficient of ?35 and ?40 dB respectively. Same antenna structure using FR4 structure is achieving good resonance at multiple frequency and broadband characteristics in C-band and X-band of the radio spectrum.

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39.
Nano particle of Fe3O4 (nFe3O4) up to 6 at% were doped in the superconducting MgB2 samples. Despite the strong ferromagnetic nature of Fe3O4, both the ac susceptibility and the resistivity measurements show that up to 4 at% of Fe3O4, T c =38 K is not changed, whereas for 6% T c decreases by 6 K. This indicates that a low concentration of Fe does not substitute either the Mg or B sites and probably occupies the intergrain spaces. For 0.5% doped Fe3O4, an increase in J c with respect to the pure MgB2 samples is observed in the lower field and temperature regions (H<2 T and 20 K) indicating an enhanced flux pinning and the magnetic activation, i.e., the interaction between the magnetic dipole of Fe ion and the vortices is weak in comparison to the effective pinning potential. Whereas, at H>2 T, J c of the doped samples is always less than that of MgB2, and the activation is dominant in comparison with the effective pinning potential provided by the doping. Flux jumps are observed in lower T and H regions for the samples doped up to 1% nFe3O4 only. Magnetization plots of higher Fe content samples exhibited clear paramagnetic background. Mossbauer measurements for the higher (4, 6 at%) nFe3O4 doped MgB2 samples show that at RT, the hyperfine field for both samples is ∼100 kOe and ∼120 kOe at 90 K. This means that the nFe3O4 particles decompose and form possibly an intermetallic Fe-B phase in the matrix.  相似文献   
40.
In the present study, the influence of Hall and ion‐slip current on steady magnetohydrodynamics mixed convective, Ohmic heating, and viscous dissipative Casson fluid flow over an infinite vertical porous plate in the presence of Soret effect and chemical reaction are investigated. The modeling equations are transformed into dimensionless equations and then solved analytically through the multiple regular perturbation law. Computations are performed graphically to analyze the behavior of fluid velocity, temperature, concentration, skin friction, Nusselt number, and Sherwood number on the vertical plate with the difference of emerging physical parameters. This study reflects that the incremental values of Casson fluid parameter and Schmidt number lead to reduction in velocity. However, fluid velocity rises due to enhancement of ion‐slip parameter but an opposite effect is observed in case of Hall parameter. In addition, the Sherwood number declines with enhancing dissimilar estimators of the chemical reaction, Schmidt number, as well as Soret number.  相似文献   
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