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EFAB: Batch Production of Functional, Fully-Dense Metal Parts with Micron-Scale Features
EFAB (Electrochemical FABrication) is a new SFF process with the potential to economically fabricate
prototypes or mass production quantities of functional, mesoscale-microscale parts and mechanisms. EFAB
generates an entire layer simultaneously-versus serially, as with most SFF. Based on electrodeposition,
EFAB allows ultra-thin layers (2-10 microns, or even submicron) that minimize stairsteps, and generates a
net-shape, fully-dense metal structure that can be homogeneous and isotropic. Minimum feature width is
approximately 25 microns, and can be reduced further. EFAB can be used to manufacture micromachines
and microelectromechanical systems (MEMS), offering significant advantages over current processes: e.g.,
true 3-D geometry, IC compatibility, low capital investment, and process automation.Mechanical Engineerin
Thermal Interface Materials Selection and Application Guidelines: In Perspective of Xilinx Virtex-5QV Thermal Management
The heat from high-power microdevices for space, such as Xilinx Virtex 4 and 5 (V4 and V5), has to be removed mainly through conduction in the space vacuum environment. The class-Y type packages are designed to remove the heat from the top of the package, and the most effective method to remove heat from the class-Y type packages is to attach a heat transfer device on the lid of the package and to transfer the heat to frame or chassis. When a heat transfer device is attached to the package lid, the surfaces roughness of the package lid and the heat transfer device reduces the effective contact area between the two. The reduced contact area results in increased thermal contact resistance, and a thermal interface material is required to reduce the thermal contact resistance by filling in the gap between the surfaces of the package lid and the heat transfer device. The current report describes JPL's FY14 NEPP task study on property requirements of TIM and impact of TIM properties on the packaging reliability. The current task also developed appratuses to investigate the performances of TIMs in the actual mission environment
Long wavelength identification of microcalcifications in breast cancer tissue using a quantum cascade laser and upconversion detection
Determining cycle time for a multi-product FPR model with rework and an improved delivery policy by alternative approach
The present study determines the common cycle time for a multi-product finite production rate (FPR) model with rework and an improved delivery policy [1] by an alternative approach. Conventional method to the multi-product FPR problem employs the differential calculus to first prove convexity of the system cost function, then to derive the optimal common production cycle time that minimizes the long-run average system cost per unit time; whereas the proposed approach obtains the optimal cycle time without the need to reference the differential calculus. Such a simplified method may help those practitioners who have insufficient knowledge of calculus to effectively manage the real-life multi-product FPR problem
Measuring Energetics of Biological Processes
Measurement of the energetics of biological processes is the key component in understanding the thermodynamic responses of homoeothermic animals to their environments. For these animals to achieve body temperature control, they must adapt to thermal-environmental conditions and variations caused by weather (the meteorological condition of a region), climate, vegetation, topography, and shelters (see Figures 2 and 3 of Chapter 1). Adaptation can take different forms as defined by Hafez (1968). Physiological adaptation is the capacity and process of adjustment of the animal to itself, to other living material, and to its external physical environment. Genetic adaptation refers to the selection and heritability of characteristics for a particular environment or climatic region. A long-term adaptive physiological adjustment is referred to as acclimatization. We know this occurs through observations of animal conformation, animal types, respiratory rate, color, behavior, food selection, etc. Since adaptation of the animal to its thermal environment requires regulation of body temperature, measurement of that adaptation through animal energetics provides an indicator of the extent and energetic cost of adaptation
The characterization of the saddle shaped nickel(III) porphyrin radical cation: an explicative NMR model for a ferromagnetically coupled metallo-porphyrin radical
Ni(III)(OETPP˙)(Br)2 is the first Ni(III) porphyrin radical cation with structural and (1)H and (13)C paramagnetic NMR data for porphyrinate systems. Associating EPR and NMR analyses with DFT calculations as a new model is capable of clearly determining the dominant state from two controversial spin distributions in the ring to be the Ni(III) LS coupled with an a1u spin-up radical
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