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排序方式: 共有231条查询结果,搜索用时 15 毫秒
1.
Bianka Rocha Saraiva Lucas Henrique Maldonado da Silva Fernando Antônio Anjo Ana Carolina Pelaes Vital Jéssica Bassi Da Silva Marcos Luciano Bruschi Paula Toshimi Matumoto Pintro 《International Journal of Food Science & Technology》2020,55(5):1962-1970
Debittered trub (brewing waste) is an important source of protein source (70.26%). Trub and whey protein were used for 5% protein enrichment of ice cream frozen by liquid nitrogen. Three formulations were elaborated: ice cream standard (ICS), ice cream with whey protein (ICW) and ice cream with trub (ICT). Chemical composition, rheological properties, texture, overrun, melting rate, scanning electron microscopy and a sensorial test were performed. Results showed that ICT presented a higher viscosity, obtained on the upward curve up to 6.76 Pa s−1, consistency index (22.96 (Pa s−1)n), hysteresis area (140.40 mPa s−1) and hardness (31113.33 g) but a lower melting rate (0.38 g min−1), overrun (13.92%) and sensorial acceptability than the other formulations. The addition of trub debittered for protein enrichment improved ice cream properties and demonstrated that it could be used as a food ingredient. 相似文献
2.
This paper presents a comparative study of the condensation heat transfer coefficients in a smooth tube when operating with pure refrigerant R134a and its mixture with lubricant Castrol “icematic sw”. The lubricant is synthetic polyol ester based oil commonly used in lubricating the compressors. Two concentrations of R134a-oil mixtures of 2% and 5% oil (by mass) were analysed for a range of saturation temperatures of refrigerant R134a between 35 °C and 45 °C. The mass flow rate of the refrigerant and the mixtures was carefully maintained at 1 g/s, with a vapour quality varying between 1.0 and 0. The effects of vapour quality, flow rate, saturation temperature and temperature difference between saturation and tube wall on the heat transfer coefficient are investigated by analysing the experimental data. The experimental results were then compared with predictions from earlier models [Int J Heat Mass Transfer (1979), 185; 6th Int Heat Transfer Congress 3 (1974) 309; Int J Refrig 18 (1995) 524; Trans ASME 120 (1998) 193]. Finally two new empirical models were developed to predict the two-phase condensation heat transfer coefficient for pure refrigerant R134a and a mixture of refrigerant R134a with Castrol “icematic sw”. 相似文献
3.
Khaled M. Al-Aribe George K. Knopf Amarjeet S. Bassi 《Microfluidics and nanofluidics》2012,12(1-4):325-335
Optically manipulating the local pH of a target solution in a microchannel, or reservoir, provides a mechanism for activating and controlling a variety of biological and chemical processes on Lab-on-a-Chip (LOC) devices and micro-total analysis systems (μ-TAS). A microscale pH gradient generator that exploits the light-activated molecular proton pumps found in the purple membranes (PM) of bacteriorhodopsin is described in this paper. The photo-electro-chemical transducer is an ultrathin layer (~13?nm) of oriented PM patches self-assembled on an Au-coated porous substrate. A biotin labeling and streptavidin molecular recognition technique is used to ensure that the extracellular side of all PM patches is attached to the porous substrate enabling unidirectional and efficient transport of ions across the transducer surface. The photo-induced proton pumps generate a flow of ions that produce a measurable change in pH between the separated solutions. The self-assembly procedure is experimentally quantified based on the capacitance characteristics of the bR membranes. The investigation confirms that the transducer is covered with the bR proton pumps at a mass density of 2.33?ng/cm2. Experimental tests also show that the proposed transducer can repeatedly generate pH gradients as high as 0.42 and absolute voltage differences as high as 25?mV when illuminated by an 18?mW, 568?nm light source. Furthermore, the ΔpH is observed to be nonlinear with respect to light intensity and exposure time. The ΔpH of the target solution is sufficient to cause a phenolphthalein indicator dye to change color or an ionic hydrogel micro-valve to expand. 相似文献
4.
A. C. Bassi 《Polymer Engineering and Science》1978,18(10):750-754
When rubber is deformed an energy input is involved which is released in part when the rubber returns to its original shape. The part which is not returned as mechanical energy is dissipated as heat. The “rebound resilience” is defined as the ratio of the energy returned to the energy applied for deformation by an indentation due to a single impact. In this experiment, a pendulum mass and a test piece, as long as they are in contact, may be considered an oscillating system having one degree of freedom in which the rubber is a Voigt model. The correlation between rebound resilience and loss angle of the rubber may thus be derived. The measurement of the contact time between pendulum indentor tip and rubber surface, in addition to the rebound resilience, allows calculation of deformation, speed and acceleration of the damped sinusoidal motion. The penetration of the spherical indentor under a constant force depends on Young's modulus. Scott found an empirical relationship among force applied, depth of indentation, radius of the indentor tip and the modulus. This relationship has been recently improved by Stiehler and coworkers, The Stiehler formula has been used here for evaluating the storage modulus of rubber vulcanizates by using the maximum force transmitted by the impacting mass and the indentation depth of the test piece at the same time. 相似文献
5.
Rajnish Kumar Rai 《Information & Communications Technology Law》2010,19(2):115-146
The amendment of patent law of India in 2005 to fulfill her international obligation under the TRIPS Agreement (World Trade Organization Agreement on Trade Related Intellectual Property Rights) was an outcome of an attempt to balance the competing interests of several stakeholders, including indigenous pharmaceutical companies, multi-national pharmaceutical companies, non-governmental organizations and civil society groups concerned with access to affordable drugs. The adverse consequence of this delicate balancing is introduction of some provisions in the Act whose compatibility with the TRIPS Agreement is questionable, and which therefore are prone to litigations. Section 107A(b) of the amended patent law dealing with parallel imports is one such provision, which, if interpreted word for word could have significant connotations for the rights of a patent owner. This article aims to examine the inconsistencies intrinsic in Section 107A(b) and discusses the divergences in the Indian patent law associated with the doctrine of exhaustion and parallel imports. This article also proposes legal amendments with a view to eliminate inconsistencies intrinsic in the section and enlarge the ambit of the exhaustion principle conceptualized therein, while concurrently remaining compliant with the TRIPS Agreement. 相似文献
6.
Vinyl carbazole (VC) functionalized ordered mesoporous silica polymer nanocomposites (SBA/VC) were synthesized by in situ radical polymerization of monomers inside the mesoporous framework and characterized for the antibacterial activity studies against gram positive and gram negative bacteria. Powder X-ray diffraction and N2 adsorption isotherms of SBA/VC nanocomposites showed the presence of mesoporous nature. The antimicrobial activity results showed increasing trend with the increase in the concentration of vinyl carbazole (VC) and the maximum antibacterial activity was achieved with SBA/VC64 nanocomposites. 相似文献
7.
Andrew Procter Andrea Bassi Jenna Kolling Llael Cox Nicholas Flanders Nadav Tanners Rochelle Araujo 《Clean Technologies and Environmental Policy》2017,19(5):1459-1474
Cities worldwide face the challenges of accommodating a growing population, while reducing emissions to meet climate mitigation targets. Public transit investments are often proposed as a way to curb emissions while maintaining healthy urban economies. However, cities face a system-level challenge in that transportation systems have cascading effects on land use and economic development. Understanding how an improved public transit system could affect urban growth and emissions requires a system-level view of a city, to anticipate side effects that could run counter to policy goals. To address this knowledge gap, we conducted a case study on the rapidly growing Research Triangle, North Carolina (USA) region, which has proposed to build a Light Railway by 2026 along a heavily used transportation corridor between the cities of Durham and Chapel Hill. At the same time, Durham County has set a goal of lowering greenhouse gas emissions by 30% from a 2005 baseline by 2030. In collaboration with local stakeholders, we developed a system dynamics model to simulate how Light Rail transit and concurrent policies could help or hinder these sustainable growth goals. The Durham–Orange Light Rail Project (D–O LRP) model simulates urban–regional dynamics between 2000 and 2040, including feedbacks from energy spending on economic growth and from land scarcity on development. Counter to expectations, model scenarios that included Light Rail had as much as 5% higher regional energy use and CO2 emissions than business-as-usual (BAU) by 2040 despite many residents choosing to use public transit instead of private vehicles. This was largely due to an assumption that Light Rail increases demand for commercial development in the station areas, creating new jobs and attracting new residents. If regional solar capacity grew to 640 MW, this would offset the emissions growth, mostly from new buildings, that is indirectly due to Light Rail. National trends in building and automobile energy efficiency, as well as federal emissions regulation under the Clean Power Plan, would also allow significant progress toward the 2030 Durham emissions reduction goal. By simulating the magnitude of technology and policy effects, the D–O LRP model can enable policy makers to make strategic choices about regional growth. 相似文献
8.
Rajnish Kurchania Sachin S. Sawant Richard J. Ball 《Journal of the American Ceramic Society》2014,97(10):3208-3215
Magnetite (Fe3O4)/polyvinyl alcohol (PVA) core–shell composite nanoparticles were successfully synthesized using a coprecipitation of ferrous and ferric chloride followed by coating with PVA. The resulting nanoparticles were characterized using X‐ray diffraction, Fourier Transform Infrared Spectroscopy, Transmission Electron Microscopy, X‐ray photo electron spectroscopy, Zeta potential measurements, UV–Vis spectroscopy, Thermogravimetric Analysis, and Vibrating Sample Magnetometry (VSM). The average particle size was 13 nm. The presence of characteristic functional groups of PVA around the core of magnetite nanoparticles was confirmed by FTIR spectroscopy while the amount of PVA (%) bound to it was estimated by TGA analysis. Zeta potential measurements made by dispersing dilute sonicated samples in a Phosphate Buffer Saline (PBS pH 7.4) confirmed that the particles were negatively charged. The stability and retention of the coating material PVA in PBS (pH7.4) over a period of time were substantiated by UV–Vis spectroscopy. Room‐temperature magnetic measurements were made with a VSM which demonstrated the superparamagnetic nature of the particles with higher saturation magnetization of 56.41 emu/g. Furthermore, in vitro cytocompatibility testing of Fe3O4/PVA core–shell composite nanoparticles was carried out on human cervix cancer cells. This confirmed a 97% cell viability with no significant cytotoxicity and thereby substantiated their biocompatibility. 相似文献
9.
Berardinelli A Cevoli C Silaghi FA Fabbri A Ragni L Giunchi A Bassi D 《Journal of food science》2010,75(7):E462-E468
Abstract: The nondestructive assessment of apricot fruit quality (Bora cultivar) was carried out by means of FT-NIR reflectance spectroscopy in the wavenumber range 12000 to 4000 cm−1. Samples were harvested at four different ripening stages and scanned by a fiber optical probe immediately after harvesting and after a storage of 3 d (2 d at 4 °C and 1 d at 18 °C); the flesh firmness (FF), the soluble solids content (SSC), the acidity (A), and the titratable acidity (malic and citric acids) were then measured by destructive methods. Soft independent modeling of class analogy (SIMCA) analysis was used to classify spectra according to the ripening stage and the storage: partial least squares regression (PLS) models to predict FF, SSC, A, and the titratable acidity were also set-up for both just harvested and stored apricots. Spectral pretreatments and wavenumber selections were conducted on the basis of explorative principal component analysis (PCA). Apricot spectra were correctly classified in the right class with a mean classification rate of 87% (range: 80% to 100%). Test set validations of PLS models showed R2 values up to 0.620, 0.863, 0.842, and 0.369 for FF, SSC, A, and the titratable acidity, respectively. The best models were obtained for the SSC and A and are suitable for rough screening; a lower power prediction emerged for the other maturity indices and the relative predictive models are not recommended. Practical Application : The results of the study could be used as a tool for the assessment of the ripening stage during the harvest and the quality during the postharvest storage of apricot fruits. 相似文献
10.