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1.
Although thoracoabdominal injuries are uncommon in the athlete, they can be catastrophic if unrecognized or if diagnosis and treatment are delayed. This article reviews thoracic, intrathoracic, abdominal, and groin injuries in the athlete, and how they can be diagnosed and managed.  相似文献   
2.
Investigational drugs are increasingly becoming less soluble in aqueous media, thus, presenting real challenges during development. Previous work has successfully demonstrated the manufacturing of pharmaceuticals using fluidized bed (FB) impregnation of APIs onto porous carriers. This study demonstrates the usefulness of FB impregnation in formulating poorly soluble drugs. We show that dissolution of Fenofibrate is greatly improved by FB impregnation onto Neusilin® (Fuji Health Science Inc, Burlington, NJ USA), a synthetic amorphous form of magnesium alumino‐metasilicate. We impregnate Neusilin® for range of loadings and examine Fenofibrate's physical state. Dissolution of impregnated formulations is drug loading dependent and loadings below 40% show great improvement (decrease) in release time compared to physical blend. Release times are further improved by milling. We also examine feasibility of coimpregnating Fenofibrate with additives and observe stability (1.5 years) of the amorphous form of Fenofibrate inside Neusilin®. This stabilization significantly improves Fenofibrate's dissolution kinetics, making our formulation comparable to one of the current market formulations, TriCor® tablets (AbbVie Inc, North Chicago, IL USA). © 2016 American Institute of Chemical Engineers AIChE J, 62: 4201–4214, 2016  相似文献   
3.
Bulk flow property characterization often requires large powder samples (tens to hundreds of grams). However, many applications have limited sample availability, due to cost, material availability, safety concerns, etc. Therefore, reducing the amount of required material is of interest. A novel compressibility method is introduced using less than 50 mg, for the materials studied here. The effect of particle size and cohesion due to capillary forces are determined using a small‐scale compressibility cell mounted on a texture analyzer. It is found that the powder bed consolidation occurred in two regimes, described using the Walker and Heckel equations. The small‐scale compressibility method was compared to known behavior at larger scales and validated against the FT4 compressibility test. It was found that bulk behavior could be observed using the small‐scale compressibility method. Additional behavior caused by small‐scale events, which are averaged out in large‐scale measurements, are revealed in the small‐scale device introduced here. © 2016 American Institute of Chemical Engineers AIChE J, 62: 4193–4200, 2016  相似文献   
4.
We report that the formation of much reported axial segregation bands in rotating cylinders loaded with different sized particles depends critically on scale and inertia. Specifically, when the ratio, , of the diameter of the cylinder to the average diameter of the particles is large, axial bands invariably appear, when is small, bands never appear, and between these extremes lies a reversible state where the presence or absence of bands depends on container rotation speed. Our results indicate that banding is associated with a Rayleigh-like instability of a granular core of fine particles, and that this instability is controlled by the inertia of the larger species – and consequently on scale.KeywordsGranular, Segregation, Mixing, Banding, ScalePACS number(s): 05.40.+j, 46.10.+z, 83.10.Hh.  相似文献   
5.
We examine the spontaneous formation of numerous previously unreported patterns in deep beds of fine grains vibrated at frequencies ranging from 10 to 100 Hz and accelerations ranging from 1 to 14 times gravity. Similarly to shallow beds, we find stripes, closed cells and labyrinthine patterns. In addition, we observe traveling waves, cannibalizing cells and other behaviors that are unexpected and remain unexplained. All of these patterns vary spatiotemporally, and unlike shallow bed patterns, are harmonic rather than subharmonic. Received: 17 May 1999  相似文献   
6.
The flow of spherical particles in a tumbling blender is investigated using discrete element methods (DEM). Simulations are performed on a collection of particles that are mono-disperse and bi-disperse in size. The mono-disperse system is primarily used to assess the quality of mixing as a function of fill level and time. Results reveal that radial convection is faster than axial dispersion transport. This slow dispersive process hinders mixing performance in this geometry. We also find that both axial dispersion and radial convection worsen as the blender fill level is increased. This trend is corroborated by recent laboratory experiments performed in an identical geometry. Particle velocity profiles indicate that the flow is composed of two regions: i) a high velocity layer cascading atop ii) a nearly ‘solid body’ rotation region. Segregating mechanisms are investigated using bi-disperse systems, which show that small particles segregate in pockets at both extremes of the axis of rotation.  相似文献   
7.
The application of computationally inexpensive modeling methods for a predictive study of powder mixing is discussed. A multidimensional population balance model is formulated to track the evolution of the distribution of a mixture of particle populations with respect to position and time. Integrating knowledge derived from a discrete element model, this method can be used to predict residence time distribution, mean and relative standard deviation of the API concentration in a continuous mixer. Low‐order statistical models, including response surface methods, kriging, and high‐dimensional model representations are also presented. Their efficiency for design optimization and process design space identification with respect to operating and design variables is illustrated.

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9.
This article examines factors related to family economic self‐sufficiency in a distressed and geographically isolated public housing community. Using data from a survey of over 400 households living in a public housing development in New York City that has received HOPE VI funding, the analysis focuses both on self‐reported reasons for joblessness and on a logistic regression model of the characteristics and resources that distinguish self‐sufficient households from those on welfare. We find that the presence of children, work experience, and especially car ownership are the most significant factors related to family economic self‐sufficiency, even controlling for income and other potentially confounding effects. These results are discussed in the context of welfare reform and the renewed emphasis in federal housing policy on strategies to promote family economic self‐sufficiency in the public housing program.  相似文献   
10.
The laminar flow in an impinging jet contactor is examined as a first step toward the development of new technology for fast mixing of viscous fluids. The flow, velocity, and stretching fields in an impinging jet contactor are quantified for low Reynolds number flow using three-dimensional numerical simulations and particle image velocimetry measurements. Computational and experimental velocity fields are in close agreement, as quantified by the velocity probability density functions. Two steady-state flow regimes are found to exist: for jet Reynolds numbers (Rej) < 10, the jets do not impinge and the velocity field scales linearly with Reynolds number; for Rej > 10, the jets begin to impinge and recirculation regions form above and below the impingement point. The magnitude of the rate-of-strain tensor is calculated as a function of Rej. While areas of essentially zero stretching occupy most of the flow domain, very high rates of stretching occur at specific locations in the flow. The maximum and average rates of stretching in the contactor increase roughly linearly as a function of Reynolds number. Mixing simulations show that no mixing occurs for the steady flow in a symmetric-jet contactor. However, mixing is improved substantially by a slight modification of the impinging jet geometry that disrupts geometric symmetry.  相似文献   
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