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排序方式: 共有1308条查询结果,搜索用时 15 毫秒
991.
Satoru Watano Hideya Nakamura Yoshihiro Wakamatsu Rajesh N Dave 《Powder Technology》2004,141(3):172-176
Fine particle coating has been conducted by using a novel rotating fluidized bed coater. The coater consists of a plenum chamber and a horizontal porous cylindrical air distributor, which rotates around its axis of symmetry inside the plenum chamber. Cohesive fine cornstarch (mass median diameter of 15 μm), a Geldart Group C powder, was used as core particle and an aqueous solution of hydroxypropylcellulose (HPC-L) was sprayed onto the cornstarch to generate a film coating. Fine particle coating was conducted under various coating levels (wt.% HPC-L) and the particle size distribution of the coated particles, release rate of an aqueous pigment (food blue No. 1), which had been pre-coated onto the initial cornstarch, and the degree of agglomeration were investigated. The relationship between the coating level and the physical properties of the coated particles was analyzed. The results indicated that coating of cohesive fine cornstarch with HPC-L could be achieved, producing a favorable prolonged release property with almost maintaining the individual single particle. 相似文献
992.
Comparison of Oleo‐ vs Petro‐Sourcing of Fatty Alcohols via Cradle‐to‐Gate Life Cycle Assessment 下载免费PDF全文
Jignesh Shah Erdem Arslan John Cirucci Julie O'Brien Dave Moss 《Journal of surfactants and detergents》2016,19(6):1333-1351
Alcohol ethoxylates surfactants are produced via ethoxylation of fatty alcohol (FA) with ethylene oxide. The source of FA could be either palm kernel oil (PKO) or petrochemicals. The study aimed to compare the potential environmental impacts for PKO‐derived FA (PKO‐FA) and petrochemicals‐derived FA (petro‐FA). Cradle‐to‐gate life cycle assessment has been performed for this purpose because it enables understanding of the impacts across the life cycle and impact categories. The results show that petro‐FA has overall lower average greenhouse gas (GHG) emissions (~2.97 kg CO2e) compared to PKO‐FA (~5.27 kg CO2e). (1) The practices in land use change for palm plantations, (2) end‐of‐life treatment for palm oil mill wastewater effluent and (3) end‐of‐life treatment for empty fruit bunches are the three determining factors for the environmental impacts of PKO‐FA. For petro‐FA, n‐olefin production, ethylene production and thermal energy production are the main factors. We found the judicious decisions on land use change, effluent treatment and solid waste treatment are key to making PKO‐FA environmentally sustainable. The sensitivity results show the broad distribution for PKO‐FA due to varying practices in palm cultivation. PKO‐FA has higher impacts on average for 12 out of 18 impact categories evaluated. For the base case, when accounted for uncertainty and sensitivity analyses results, the study finds that marine eutrophication, agricultural land occupation, natural land occupation, fossil depletion, particulate matter formation, and water depletion are affected by the sourcing decision. The sourcing of FA involves trade‐offs and depends on the specific practices through the PKO life cycle from an environmental impact perspective. 相似文献
993.
Dave Sonnier 《电子设计技术》2006,13(7):96-96
芯片设计在许多方面都面临各种不同的挑战,需要网络和系统设计专业知识以及芯片技术来解决。归根结底,客户总是希望降低总系统成本,提高产品性能和赢利性。这样,设计网络和系统芯片的公司能否成功满足客户需求,将决定它们在今后几年的发展前途。 相似文献
994.
Koval D.O. Xinlie Zhang Propst J. Coyle T. Arno R. Hale R.S. Jr. 《Industry Applications Magazine, IEEE》2003,9(1):32-41
Several key reliability indices for industrial and commercial customers are a knowledge of the reliability and the frequency and duration of load point interruptions within their electrical power system networks at their facilities. A reliable equipment data source is key to an accurate analysis. Data sources, such as The IEEE Gold Book provide the user with the necessary data parameters to evaluate the reliability of industrial and commercial power system network configurations. An accurate understanding of component reliability and maintenance actions will provide the necessary availability indices for a reliability analysis approach. This paper discusses The IEEE Bold Book Standard Network and three reliability models: spreadsheet reliability model; GO software tool; and minimal cut-set reliability analysis methodology. 相似文献
995.
S. N. Fisher A. M. Guénault A. J. Hale G. R. Pickett 《Journal of Low Temperature Physics》2000,121(5-6):393-398
We have made the surprising discovery that the thermal damping of a vibrating wire resonator in superfluid
3
He-B at ultra low temperatures is considerably depressed when a second wire in the vicinity is driven supercritically. The damping of a vibrating wire resonator at low velocities in the B-phase arises from the scattering of quasiparticle excitations and has a temperature dependence proportional to the Boltzmann factor exp(–/kT) at low temperatures. At higher velocities (v>vL/3), the wire breaks Cooper pairs and emits a quasiparticle beam. At first sight it seems paradoxical that heating the superfluid can reduce the quasiparticle flux on a neighbouring wire. We can only understand this on the basis that vorticity emitted by the supercritical wire shields, via Andreev reflection, part of the background quasiparticle flux from reaching the other wire. If this interpretation is correct, these techniques will provide a sensitive probe of vortex dynamics in the ultra low temperature regime. 相似文献
996.
P. Brussaard S. N. Fisher A. M. Guénault A. J. Hale G. R. Pickett 《Journal of Low Temperature Physics》2000,121(5-6):555-560
We present novel experiments on a disk of 98% aerogel oscillating in superfluid
3
He at ultralow temperatures. The aerogel dik is attached to a goal post shaped vibrating wire resonator and immersed in liquid
3
He cooled by a Lancaster style nuclear cooling stage. At low pressures we see no evidence for superfluidity within the aerogel down to our base temperature of below <0.11Tc. At higher pressures we observe large temperature dependent frequency shifts, reminiscent of torsional oscillator experiments. We find the transition temperature at 5 bar to be around 600K. The response of the resonator is highly non linear when the helium in the aerogel is superfluid. The resonant frequency decreases strongly with increasing wire amplitude. This offers an exciting new technique for measuring the superfluid properties of
3
He in aerogel in the ultralow temperature regime. 相似文献
997.
Pair programming purportedly delivers quality code with little productivity loss. The authors' field study, outside the pair programming environment, shows that two-person teams working independently are more productive than those working concurrently; agile methods may overcome inherent productivity losses of concurrent development. This research contrasts starkly with our field study findings. We decided to reexamine our earlier productivity data from teams of two and ask: Would our previous findings of concurrent-work productivity loss be reversed if we look only at programming pairs rather than teams of all sizes? If so, we could conclude that pairs are naturally more productive than larger teams, regardless of the collaborative process. If not, we could conclude that the collaboration mechanisms prescribed in pair programming might overcome a natural loss of productivity from concurrent work. We offer these findings and their implications as a benchmark against which we might measure the potential of pair programming practices. 相似文献
998.
A Bidirectional Deposition Model of Wax Crayons 总被引:1,自引:0,他引:1
We present a physically inspired model of wax crayons, which synthesizes drawings from collections of user‐specified strokes. Paper is represented by a height‐field texture, and a crayon is modeled with a 2D mask that evolves as it interacts with the paper. The amount of wax deposition is computed based on the crayon contact profile, contact force and friction. Previously deposited wax is smeared by crayon action, based on wax softness and contact information. Deposited wax can also be carved from the paper by the crayon and redeposited at another location. The distributed wax is rendered using a simplified Kubelka–Monk model, which approximates light transmission and scattering effects. 相似文献
999.
This work aimed to produce poly(acrylonitrile-co-itaconic acid) (P(AN-co-IA)) nanocomposites with poly(3,4-ethylenedioxythiophene) (PEDOT) and poly(3-methoxythiophene) (PMOT). An anionic surfactant sodium dodecyl benzene sulphonate was used in emulsion polymerization for nanocomposite production. Incorporations of PEDOT and PMOT on the nanoparticles were characterized by scanning electron microscopy (SEM), atomic force microscopy, Fourier transform infrared-attenuated total reflectance spectroscopy and ultra-violet spectroscopy. These nanoparticles were blended with PAN and the blends were electrospun to produce P(AN-co-IA)–polythiophene-derivative-based nanofibres, and the obtained nanofibres were characterized by SEM and energy dispersive spectroscopy. In addition, electrochemical impedance studies conducted on nanofibres showed that PEDOT and PMOT in matrix polymer P(AN-co-IA) exhibited capacitive behaviour comparable to that of ITO–PET. Their capacitive behaviour changed with the amount of electroactive polymer. 相似文献
1000.
Ömer Güler S. Hale Güler Veyis Selen M. Gokhan Albayrak Ertan Evin 《Fullerenes, Nanotubes and Carbon Nanostructures》2016,24(2):123-127
Multi-layer graphene was produced through synthesized expanded graphite (EG) liquid exfoliation using organic solvent. Hexagonal graphite (HG) was used as a starting material. HG was mixed with an acidic mixture, dried, rand subjected to thermal treatment. After this process, EG was obtained. This obtained EG was sonicated for 1 h via an ultrasonic homogenizer by blending an organic solvent. Samples were subjected to SEM, TEM, FTIR, and UV-Vis/NIR spectroscopy investigations. After the investigations, it was shown that nano-size graphene sheets were obtained. 相似文献