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51.
In a network of high performance workstations, many workstations are underutilized by their owners. The problem of using these idle cycles for solving computationally intensive tasks by executing a large task on many workstations has been addressed before and algorithms with O(N2) time and O(N) space for choosing the optimal subset of workstations out of N workstations were presented. We improve these algorithms to reduce the running time to O(N log N), while keeping the space requirement the same. The proposed algorithms are particularly useful for SPMD parallelism where computation is the same for all workstations and the data space is partitioned between the workstations  相似文献   
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We describe a smart-pixel circuit that permits the use of a GaAs/AlGaAs multiple quantum well diode to be used both as a detector for data input and a modulator for data output. The module provides the ability to double the number of inputs or outputs to the array and is well suited to cascaded optoelectronic system architectures that require bidirectional communition.  相似文献   
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Creating defect tolerant lead‐free halide perovskites is the major challenge for development of high‐performance photovoltaics with nontoxic absorbers. Few compounds of Sn, Sb, or Bi possess ns2 electronic configuration similar to lead, but their poor photovoltaic performances inspire us to evaluate other factors influencing defect tolerance properties. The effect of heavy metal cation (Bi) transmutation and ionic migration on the defects and carrier properties in a 2D layered perovskite (NH4)3(Sb(1?x)Bix)2I9 system is investigated. It is shown, for the first time, the possibility of engineering the carriers in halide perovskites via metal cation transmutation to successfully form intrinsic p‐ and n‐type materials. It is also shown that this material possesses a direct–indirect bandgap enabling high absorption coefficient, extended carrier lifetimes >100 ns, and low trap densities similar to lead halide perovskites. This study also demonstrates the possibility of electrical poling to induce switchable photovoltaic effect without additional electron and hole transport layers.  相似文献   
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Journal of Materials Science: Materials in Electronics - Chemical vapor deposition (CVD) is a promising method for producing high-quality two-dimensional (2D) transition metal dichalcogenides...  相似文献   
57.
Rajagopalan  N. R.  Krishnamoorthy  P.  Jayamoorthy  K. 《SILICON》2018,10(3):1051-1061
Silicon - Non liner optical single crystals of bis(thiourea) lead chloride (BTLC), belonging to the semi-organic material category, have been prepared by a slow solvent evaporation process. The...  相似文献   
58.
Heavy metals in maternal and cord blood   总被引:8,自引:0,他引:8  
Heavy metal concentrations have been determined in maternal and cord blood samples collected from mothers in the age group 20-25 years with full-term neonates (37-40 weeks). The concentrations of Pb, Cd, Cu and Zn were found to be low in cord blood as compared to mother's blood and the ratio between cord blood and maternal blood for the respective elements was found to be approximately 0.80, 0.86, 0.47 and 0.40. On the other hand, the concentrations of Fe and Mg in the mother's blood were found to be lower than those in the cord blood. Prenatal exposure to lead in Mumbai, though low (5.1 microg/dl), is approximately 2-3 times higher than that observed in Canada or Italy. A strong correlation (r = 0.79) between the maternal and cord blood lead levels has been observed during the present study.  相似文献   
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Liquid metal(LM)has become an emerging material paradigm in the electromagnetic interference shielding field owing to its excellent electrical conductivity.However,the processing of lightweight bulk LM composites with finite package without leakage is still a great challenge,due to high surface tension and pump-out issues of LM.Here,a novel confined thermal expansion strategy based on expandable microsphere(EM)is proposed to develop a new class of LM-based monoliths with 3D continuous conductive network.The EM/LM monolith(EM/LMm)presents outstanding performance of lightweight like metallic aerogel(0.104 g cm-1),high strength(3.43 MPa),super elasticity(90%strain),as well as excellent tailor ability and recyclability,rely on its unique gas-filled closed-cellular structure and refined LM network.Moreover,the assembled highly conducting EM/LMm exhibits a recorded shielding effectiveness(98.7 dB)over a broad frequency range of 8.2-40 GHz among reported LM-based composites at an ultra-low content of LM,and demonstrates excellent electromagnetic sealing capacity in practical electronics.The ternary EM/LM/Ni monoliths fabricated by the same approach could be promising universal design principles for multifunctional LM composites,and applicable in magnetic responsive actuator.  相似文献   
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