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951.
Vasudevan Pillai R. Remya Rajendran Jose Varghese Sundararajan Parani El Hadji Mamour Sakho Oluwatobi S. Oluwafemi Sabu Thomas 《应用聚合物科学杂志》2021,138(10):49985
In this work, we have successfully synthesized epoxidized poly(styrene-block-butadiene-block-styrene) with the highest epoxidation degree (55 mol%) for the first time by using metachloroperbenzoic acid method. This highly epoxidized styrene-butadiene-styrene (eSBS) block copolymer exhibited good compatibility with the epoxy (diglycidylether of bisphenol-A)/ eSBS block copolymer- 4,4′-diamino diphenyl methane blend. Transmission electron microscope images showed that the eSBS block copolymer formed spherical nanostructure morphology within the blend due to reaction induced phase separation. The addition of eSBS block copolymer in the system significantly improved the wetting parameters such as hydrophilicity, surface free energy, work of adhesion, spreading coefficient and Girifalco-Good's interaction parameter values, which are discussed in detail. The as-prepared self-assembled nanostructured epoxy system will be useful in highly toughened coating applications such as aircraft, automobile, and flooring industries. 相似文献
952.
Local Structural Rearrangements and Evolution of Relaxor State in the Complex Perovskite (Ba1−xPbx) (In0.50Nb0.50) O3 下载免费PDF全文
Local structural rearrangements in lead‐based complex perovskites of the type (Ba1?xPbx)(In0.50Nb0.50)O3 responsible for transition from ferroelectric [Ba(In0.50Nb0.50)O3] to relaxor [Pb(In0.50Nb0.50)O3] are examined by careful analysis of their Raman spectra. Subtle changes in the bonding brought about by the differences in the chemical nature of A‐ and B‐site cations have been correlated with the dynamic A–O–B coupling. Deviations in the local structure as a result of such bonding preferences have been confirmed by studying the changes in the Raman spectra when Nb5+ is substituted by Sn4+ as the third B‐site cation. 相似文献
953.
Design of Aminobenzothiazole Inhibitors of Rho Kinases 1 and 2 by Using Protein Kinase A as a Structure Surrogate 下载免费PDF全文
Russell A. Judge Anil Vasudevan Victoria E. Scott Gricelda H. Simler Steve D. Pratt Marian T. Namovic C. Brent Putman Ana Aguirre Vincent S. Stoll Mulugeta Mamo Steven I. Swann Steven C. Cassar Connie R. Faltynek Karen L. Kage Janel M. Boyce‐Rustay Adrian D. Hobson 《Chembiochem : a European journal of chemical biology》2018,19(6):613-621
We describe the design, synthesis, and structure–activity relationships (SARs) of a series of 2‐aminobenzothiazole inhibitors of Rho kinases (ROCKs) 1 and 2, which were optimized to low nanomolar potencies by use of protein kinase A (PKA) as a structure surrogate to guide compound design. A subset of these molecules also showed robust activity in a cell‐based myosin phosphatase assay and in a mechanical hyperalgesia in vivo pain model. 相似文献
954.
Jianshu Li Zhiping Lin Sirajudeen Gulam Razul A. Anil Kumar Yuanjin Zheng Chong-Meng See 《Multidimensional Systems and Signal Processing》2018,29(2):537-561
Direction of Arrival (DOA) estimation is one of the major tasks in array signal processing. In this paper, a new DOA estimation method is proposed using a rotational uniform linear array (RULA) consisting of omnidirectional sensors. The main contribution of the proposed method is that the number of distinguishable signals is larger than the methods in the literature with a uniform linear array consisting of the same number of omnidirectional sensors. Moreover, the new method can effectively reduce unknown spatial noises using a generalized complement projection matrix under the RULA framework. Simulations are presented to illustrate the effectiveness of the proposed method and comparison with some existing DOA estimation methods is also made. 相似文献
955.
Vasudevan Madampu Suryasarman Santosh Biswas Aryabartta Sahu 《Journal of Electronic Testing》2018,34(1):83-103
Software-based self-testing (SBST) is introduced for at-speed testing of processors, which is difficult with any of the external testing techniques. Evolutionary approaches are used for the automatic synthesis of SBST programs. However, a number of hard-to-detect faults remain unidentified by these autogenerated test programs. Also, these approaches have considered fault models which have low correlation with the gate-level fault models. This paper presents a greed-based strategy, where the instruction sequences that detect the freshly identified faults are preserved throughout the evolutionary process to identify the hard-to-test faults of the processor. Subsequently, the overall coverage is also improved. A selection probability is estimated from the testability properties of the processor components and assigned to every instruction to accelerate the test synthesis. The range of performance and scalability are comprehensively evaluated on a configurable MIPS processor and a full-fledged 7-stage pipeline SPARC V8 Leon3 soft processor using behavioral fault models. The efficacy of our approach was explained by demonstrating the correlation between behavioral faults and gate-level faults of MIPS processor for the proposed scheme. Experimental results show that improved coverages of 96.32% for the MIPS processor and 95.8% for the Leon3 processor are achieved in comparison with the conventional methods, which have about 90% coverage on the average. 相似文献
956.
Numericalanalysisofmicrowaveheatingbehavioursofceramicmaterialsinsingletriodecavity¥WuSuandLuAnil(TsinghuaUniversity.Beijing)... 相似文献
957.
For assessment of time-dependent reliability or risk of aging ship structures, it is essential to have a mathematical model which provides the statistical characteristics (mean, variance, distribution) of corrosion wastage as a function of time (i.e., ship age). The aim of the present work is to develop such a model for low alloy carbon steel plates used for the structure of seawater ballast tanks in ships. Measurement data of structural wastage due to corrosion for such ship steel plates is collected and the statistical characteristics of corrosion loss and rate are quantified by statistical analysis in terms of ship age. The results and insights developed in the present study will be useful for predicting the wastage of corrosion in seawater ballast tank structures of ships. They will also be useful for designing corrosion tolerant structures subjected to the seawater environment. 相似文献
958.
Radu Pavel Anil Srivastava 《The International Journal of Advanced Manufacturing Technology》2007,33(3-4):412-418
In many grinding applications, the material removal rate is constrained by the undesired thermal effects such as surface burn,
tensile residual stresses, and micro-cracks on the ground parts. Thermal damage is a common productivity limitation factor
for conventional grinding wheels largely employed in industry due to their convenient cost and known behavior. The development
of superabrasive materials having high heat conduction coefficients allowed for higher material removal rates, pushing up
the limits of productivity previously achieved with conventional wheels. This paper presents the results of a comparative
investigation of maximum surface temperatures generated during the plunge grinding of 52100 steel using Al2O3 and CBN wheels. The experiments were conducted under wet as well as dry grinding conditions. The temperatures measured experimentally
were compared to those determined analytically. A discussion relative to heat partition coefficients concludes this paper. 相似文献
959.
Orange-red light-emitting Sm3+-doped cerium oxide (CeO2) ceramic powder with various concentrations of Sm3+ ions was prepared through a sol-gel process. X-ray diffraction and Rietveld analysis confirmed the formation of a purely cubic structure with a space group of . The lattice parameters and unit cell volumes of the CeO2:Sm3+ powder increased with the concentration of Sm3+ ions. The energy-dispersive X-ray spectra and corresponding mapping images confirmed the elemental composition and adequate dispersion of all elements in the CeO2:Sm3+ powder. A broad excitation band at approximately 365?nm was observed in the excitation spectra of CeO2:Sm3+ phosphors owing to the charge transfer transition from O 2p to Ce 4f orbitals. The Sm3+ doped CeO2 phosphors emitted sharp luminescence with a main peak at 615?nm under excitation at 360?nm. The spectral analysis revealed that the CeO2:Sm3+ phosphors exhibited strong orange-red emission. Concentration quenching was observed in the CeO2:Sm3+ phosphors with 0.5?mol% of critical concentration of Sm3+ ions due to dipole dipole interaction of two nearest Sm3+ ions. The quantum efficiency was observed as high as 58%. The thermal stability of the present materials was estimated with the evaluation of activation energy as 0.31?eV. The broad excitation band and sharp orange–red emission indicated the potential use of CeO2:Sm3+ phosphors for white light-emitting diodes. 相似文献
960.
Hari Krishna Vydana Sudarsana Reddy Kadiri Anil Kumar Vuppala 《Circuits, Systems, and Signal Processing》2016,35(5):1643-1663
The objective of this work is to develop a rule-based emotion conversion method for a better emotional perception. In this work, performance of emotion conversion using the linear modification model is improved by using vowel-based non-uniform prosody modification. In the present approach, attempts were made to integrate features like position and identity for addressing the non-uniformity in prosody generated due to the emotional state of the speaker. We mainly concentrate on the parameters such as strength, duration and pitch contour of vowels at different parts of the sentence. The influence of emotions on the above parameters is exploited to convert the speech from neutral emotion to the target emotion. Non-uniform prosody modification factors for emotion conversion are based on the position of vowels in the word, and the position of the word in the sentence. This study is carried out by using Indian Institute of Technology-Simulated Emotion speech corpus. Evaluation of the proposed algorithm is carried out by a subjective listening test. From the listening tests, it is observed that the performance of the proposed approach is better than the existing approaches. 相似文献