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991.
Noncentrosymmetric (NCS) tetrel pnictides have recently generated interest as nonlinear optical (NLO) materials due to their second harmonic generation (SHG) activity and large laser damage threshold (LDT). Herein nonmetal-rich silicon phosphides RuSi4P4 and IrSi3P3 are synthesized and characterized. Their crystal structures are reinvestigated using single crystal X-ray diffraction and 29Si and 31P magic angle spinning NMR. In agreement with previous report RuSi4P4 crystallizes in NCS space group P1, while IrSi3P3 is found to crystallize in NCS space group Cm, in contrast with the previously reported space group C2. A combination of DFT calculations and diffuse reflectance measurements reveals RuSi4P4 and IrSi3P3 to be wide bandgap (Eg) semiconductors, Eg = 1.9 and 1.8 eV, respectively. RuSi4P4 and IrSi3P3 outperform the current state-of-the-art infrared SHG material, AgGaS2, both in SHG activity and laser inducer damage threshold. Due to the combination of high thermal stabilities (up to 1373 K), wide bandgaps (≈2 eV), NCS crystal structures, strong SHG responses, and large LDT values, RuSi4P4 and IrSi3P3 are promising candidates for longer wavelength NLO materials.  相似文献   
992.

In recent days, wireless sensor networks (WSN) plays a major role in the real time applications like military battlefield surveillance, industrial process monitoring, machine health monitoring and so on. In WSN, selecting the cluster head (CH) is the challenging task. CH selection is done by considering parameters of single layer only. In cross layer protocol more than one layers are considered for inter related parameters such as integration of MAC/physical layer and integration routing/MAC/physical layers. The main drawback of layer-based approach is not considering the effect on improvement of particular layer parameter to other layer parameters. In this paper, new cross layer technique for energy efficient module is designed to address the energy efficiency issues, which is common to all layers and used to optimize the energy from one layer parameter by others. Nowadays everything is possible with the help of Internet, so sharing the information between WSN and TCP through the energy efficient cross layer can be done. It is done with transport layer to enhance the application filed to be reliably connected to the web. In this paper, dynamically adapted sleep scheduling mechanism is used with residual energy of each node. Virtual end-to-end packet rate selection and congestion control feedback mechanism are considered for end to end delay. This reduces the packet loss with the support of data-rate adaptation technique.

  相似文献   
993.
Wireless Personal Communications - Authentication is a term very important for data communication security. We see many frauds due to authentication failure. The problem manifolds when...  相似文献   
994.
Breev  I. D.  Yakovleva  V. D.  Kudryavtsev  O. S.  Baranov  P. G.  Mokhov  E. N.  Anisimov  A. N. 《Semiconductors》2021,55(3):328-332
Semiconductors - The effects of the high-temperature (T = 1880°C) diffusion of beryllium ions and of electron irradiation on the optical properties of single-crystal aluminum nitride is...  相似文献   
995.
Journal of Communications Technology and Electronics - The possibility of using millimeter-wave (MM) satellite communication lines in the Arctic to ensure reliable and high-speed communication is...  相似文献   
996.
Analog Integrated Circuits and Signal Processing - Remarkable progress in the field of wireless communication has created a research interest for Viterbi decoder with long duration of battery life,...  相似文献   
997.
Urdu is a widely spoken language in the Indian subcontinent with over 300 million speakers worldwide. However, linguistic advancements in Urdu are rare compared to those in other European and Asian languages. Therefore, by following Text Retrieval Conference standards, we attempted to construct an extensive text collection of 85 304 documents from diverse categories covering over 52 topics with relevance judgment sets at 100 pool depth. We also present several applications to demonstrate the effectiveness of our collection. Although this collection is primarily intended for text retrieval, it can also be used for named entity recognition, text summarization, and other linguistic applications with suitable modifications. Ours is the most extensive existing collection for the Urdu language, and it will be freely available for future research and academic education.  相似文献   
998.
Journal of Engineering Physics and Thermophysics - A study is made of the evolution of pulsed pressure perturbations in a pipeline filled with a gas–droplet medium, which represents...  相似文献   
999.
Materials Science - We develop new methods of the laboratory defectometry of biocorroded microareas in structural steels based on the quantitative analysis of variations of their roughness. We...  相似文献   
1000.
Journal of Engineering Physics and Thermophysics - An experimental investigation has been conducted into the pyrolysis of typical medical waste components in a fixed-bed reactor with a view to...  相似文献   
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