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31.
The viscoelastic response of plasticized PVC was determined from stress-relaxation data over a wide range of time at different temperatures. The relaxation modulus as a function of time was determined from these data. The relaxation curves were then shifted horizontally to obtain a master curve at a reference temperature. The amount of shift was evaluated using the WLF equation. The coefficients C and C used in the equation for the PVC were determined according to the method of reduced variables. 相似文献
32.
S. L. Oswal R. G. Sindhe A. T. Patel J. P. Dave S. G. Patel B. M. Patel 《International Journal of Thermophysics》1992,13(4):617-628
Viscosities of several mono-, di-, and trialkylamines have been measured in the temperature range 298 to 333 K. It is observed that viscosities are highly dependent on shape, size, and association through H-bond or through dipole. Following the transition state theory, energy, Gibbs free energy, and entropy of activation of viscous flow have been calculated. The values of expansion energy for these liquids have also been calculated using free volume theory, and subsequently amines have been classified as volume-restrained or energy-restrained liquids. The group contribution method of Van Velzen, Cardozo, and Langenkamp for estimating viscosity has been examined with the present and literature data, and the new group contribution increments N
i and B
i for amines have been evaluated. 相似文献
33.
Corey Nelson Tyler Mrozowich Darren L. Gemmill Sean M. Park Trushar R. Patel 《International journal of molecular sciences》2021,22(1)
Flavivirus genus includes many deadly viruses such as the Japanese encephalitis virus (JEV) and Zika virus (ZIKV). The 5′ terminal regions (TR) of flaviviruses interact with human proteins and such interactions are critical for viral replication. One of the human proteins identified to interact with the 5′ TR of JEV is the DEAD-box helicase, DDX3X. In this study, we in vitro transcribed the 5′ TR of JEV and demonstrated its direct interaction with recombinant DDX3X (Kd of 1.66 ± 0.21 µM) using microscale thermophoresis (MST). Due to the proposed structural similarities of 5′ and 3′ TRs of flaviviruses, we investigated if the ZIKV 5′ TR could also interact with human DDX3X. Our MST studies suggested that DDX3X recognizes ZIKV 5′ TR with a Kd of 7.05 ± 0.75 µM. Next, we performed helicase assays that suggested that the binding of DDX3X leads to the unwinding of JEV and ZIKV 5′ TRs. Overall, our data indicate, for the first time, that DDX3X can directly bind and unwind in vitro transcribed flaviviral TRs. In summary, our work indicates that DDX3X could be further explored as a therapeutic target to inhibit Flaviviral replication 相似文献
34.
Manu Kumar Sang-Min Chung Ganuskh Enkhtaivan Rahul V. Patel Han-Seung Shin Bhupendra M. Mistry 《International journal of molecular sciences》2021,22(5)
In this study, we have introduced newly synthesized substituted benzothiazole based berberine derivatives that have been analyzed for their in vitro and in silico biological properties. The activity towards various kinds of influenza virus strains by employing the cytopathic effect (CPE) and sulforhodamine B (SRB) assay. Several berberine–benzothiazole derivatives (BBDs), such as BBD1, BBD3, BBD4, BBD5, BBD7, and BBD11, demonstrated interesting anti-influenza virus activity on influenza A viruses (A/PR/8/34, A/Vic/3/75) and influenza B viral (B/Lee/40, and B/Maryland/1/59) strain, respectively. Furthermore, by testing neuraminidase activity (NA) with the neuraminidase assay kit, it was identified that BBD7 has potent neuraminidase activity. The molecular docking analysis further suggests that the BBD1–BBD14 compounds’ antiviral activity may be because of interaction with residues of NA, and the same as in oseltamivir. 相似文献
35.
Silicon - In this paper, a compact 2D analytical modelling of surface potential and simulation of Si-Ge hetero-junction Dual Material Gate Vertical t-shape T-FET is presented. In the proposed... 相似文献
36.
Solay Leo Raj Singh Sarabdeep Kumar Naveen Amin S. Intekhab Anand Sunny 《SILICON》2021,13(12):4633-4640
Silicon - In this treatise, we have proposed a Single Material Gate–Dual Gate Impact Ionization Metal Oxide Semiconductor (SMG DG-IMOS) based Pressure Sensor. The pressure sensor has the most... 相似文献
37.
Polyurethanes were prepared from toluene diisocyanate (TDI), 1-4-butane diol (BDO) and polycaprolactone-based triols with varying molecular weights. Among each molecular weight triol-based urethane, hard segment content was varied from 20% to 70%. Differential scanning calorimetry, tensile testing, and Iosipescu shear testing were done on all the various urethanes prepared. Thermal characterization data revealed the dependence of phase separation on hard segment content as well as on the triol molecular weight. Tensile data and Iosipescu shear data further confirmed the observations made from the DSC data. The data further indicated that phase separation can greatly improve the modulus of cross-linked segmented urethanes. Adhesion of these urethanes to glass surface was evaluated using soda-lime float glass plate. Urethane samples were cast on the air side of the glass plates and adhesion was measured in shear mode. Adhesion data indicated that in addition to hard segment content, modulus, cross-link density, and molecular weight of the triols, phase separation seems to be a major factor in controlling adhesion. Surfaces of the failed adhesion samples were also analyzed and the failure mode was found to be cohesive, in varying degree, with the different urethane systems. 相似文献
38.
G. T. Jones L. A. Glasgow L. E. Erickson S. A. Patel C. H. Lee 《Chemical Engineering Communications》1990,97(1):181-196
Understanding the dynamic phenomena of viability loss of shear sensitive cells and bubble breakage and coalescence within airlift reactors requires knowledge of local, liquid-phase hydrodynamics. The laser-Doppler velocimeter (LDV) is a non-invasive instrument which may be used to obtain this information. Experimental procedures and software were developed to detect and measure Doppler bursts in two-phase flow in a split-cylinder airlift reactor. Off-line analysis of the data indicated a detection rate approximately one order of magnitude greater than that observed using an available commercial frequency tracker. Approximately 400 to 500 observations are needed for the ensemble mean to characterize the local mean velocity to within ±5% for a superficial gas velocity of 10.4 cm/s, the highest superficial gas velocity used in these studies. The limitations, prospects, and signal-processing options for LDV in this application are also discussed 相似文献
39.
Influence of Grain Size on Ferroelastic Toughening and Piezoelectric Behavior of Lead Zirconate Titanate 总被引:1,自引:0,他引:1
Lead zirconate titanate specimens, at composition Zr48.9+- 1.0 / Ti51.1+-1.0 of grain sizes ranging from 0.5 to 15 (μm were prepared by hot pressing. The fracture toughness showed a 40% increase in the fine-grained specimens. Poling produced anisotropy in the fracture toughness. A tensor representation for the fracture toughness, now a function of the crack plane normal and the poling direction, is developed. The maximum and minimum values in the toughness tensor are shown to be related to the unpoled toughness by a simple phenomenological relationship. We also find that the piezoelectric coefficient, d33 , shows a slight increase for the fine-grained specimens, which is in conflict with the general view that smaller-grained materials can sustain vanishingly small values of spontaneous polarization. 相似文献
40.