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1.
Three disparate food systems (gummy candy, Mozzarella cheese, and cooked ham) were characterized for their viscoelastic behavior under isothermal conditions over an extended frequency range of 10−3 to 104 Hz using broadband viscoelastic spectroscopy (BVS). The materials were tested for any stress-induced fluid flow. However, no evidence of fluid flow was found under the tested frequency range. Validity of time–temperature superposition for the selected materials was also tested and compared with data from BVS.  相似文献   
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Tracking signals are used to determine whether a sequence of forecasts is unbiased. We analyse a version of the CUSUM tracking signal that is based on the unsmoothed average mean absolute deviation of forecasting errors. We make the common assumption that demand values in different periods are independently, identically, and normally distributed. We show that, when forecast errors in different periods are also normal iid, this version of the tracking signal can indicate that the sequence is not unbiased even when it is unbiased. We suggest a simple modification to the tracking signal that serves to eliminate this flaw.  相似文献   
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Snake venom hyaluronidases known as “spreading factor” are not extensively studied. Recently, it is argued that beyond its role as a spreading factor, venom hyaluronidase (HYL) deserves to be explored as a possible therapeutic target for inhibiting the systemic distribution of venom/toxins and also for minimizing local tissue destruction. In this context, in the present study, a low-molecular weight HYL has been isolated from Bungarus caeruleus (Indian krait) venom by single step chromatography on HPLC system. The apparent molecular weight determined by SDS-PAGE is 14 ± 2 kDa, as confirmed by zymogen study and LC–MS as well. The enzyme had optimal pH 6 and temperature 37°C. The Michaelis–Menten constant (Km) was found to be 8.48 µg/mL at 37°C. The activity of purified enzyme was completely inhibited by Ba2+ metal ion and N-acetyl imidazole group-specific agents. This work yielded a highly active HYL from B. caeruleus the first one to be isolated. Further studies on its pharmacological actions will be interesting to develop lead molecules for better management of snakebite.  相似文献   
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Several high‐energy‐density strained polycyclic compounds nitromethyl‐l,3‐bishomocubane (NMBHC), nitromethylene‐1,3‐bishomocubane (NMyBHC), and bis(nitromethyl)‐1,3‐bishomocubane (DNTMBHC), which were synthesized for the first time from bishomocubanone, hold potential for application as standalone fuels in liquid bipropellant systems or as additives in liquid and solid propellant formulations. DFT analysis at the B3LYP/6‐31G(d) level of theory was employed to optimize the geometries of the compounds and to determine their densities, heats of formation, and various thermodynamic properties. The density specific impulse, determined by using equilibrium thermodynamics, demonstrated an improvement of 75 s for NMBHC and NMyBHC over standard hydrocarbons. The specific impulse with ammonium perchlorate showed an improvement of 25–30 s over hydroxy‐terminated polybutadiene. Thermogravimetric analysis revealed that NMBHC, NMyBHC, and DNTMBHC evaporated readily with activation energies of 58.8, 69.2, and 74.5 kJ mol?1, respectively.  相似文献   
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Journal of Thermal Analysis and Calorimetry - The solar collector (reflector and receiver) is the primary device being used in the concentrating solar power technologies for tapping the solar...  相似文献   
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