Ferrite powder has been directly bonded to the surface of poled lead zirconate titanate (PZT-4) using direct laser sintering.
The resultant cohesion between the metal and ceramic is extremely good although care must be taken with the processing in
order to limit the damage inflicted upon the PZT. Four point bending suggests that the strength of the processed samples has
reduced to 60 MPa as compared to 76 MPa for the unprocessed ceramic. Electrical and piezoelectric measurements shows that
the laser sintering had caused mechanical damage to a depth of 550 μm and thermal damage (depoling) to a depth of 800 μm. 相似文献
A project is a specific effort to create a unique product, so it is a favorable place for knowledge creation and development. Knowledge can be transferred inside and outside projects and their parent project-based organizations, thus affecting project performance and organizational competitiveness. However, the current research on the elements and outcomes of knowledge transfer (KT) in the project environment lacks completeness and clarity, and that on the different levels of KT is fragmented. This study aims to conduct comprehensive research to determine and link the elements and outcomes of KT in the project environment. The authors systematically analyzed the relevant literature from 2000 to 2021, which showed an increasing publication trend. They divided KT in the project environment into three levels according to the transfer scenario: Intra-project, cross-project, and cross-organizational KT. Five-dimensional transfer elements and two-dimensional transfer outcomes were then identified and analyzed from previous literature. Lastly, the relationships between the transfer elements and outcomes were gathered to create a comprehensive model. Importantly, the knowledge gap in the current literature was highlighted, and future research directions were put forward. This study builds a theoretical framework linking transfer elements to outcomes that can serve as a basis for scholars and practitioners to develop effective strategies for KT in the project environment. 相似文献
This study aimed at preparing and evaluating the europium oxide–reduced graphene oxide (rGO) composites. Inorganic nanoparticles anchored onto rGO sheets through a facile sonochemical method. The resultant products were characterized by FT-IR, XRD, SEM. Their activity in biomolecules’ analysis were examined by cyclic voltammetry. The rectified electrodes revealed an incredibly electroactive manner. The obtained progress provided excellent materials for scrutiny of biomolecules. The linear relationship was used in the region of 100–1500 µM ascorbic acid (AA), 50–600 µM dopamine (DA), and 10–700 µM uric acid (UA), between current intensities and concentrations. The detection restrictions (LOD) (S/N?=?3) decreased to 8 µM, 1.1 µM and 0.085 µM for AA, DA and UA respectively by differential pulse voltammetry (DPV). 相似文献
In studying the problem of the nonlinear viscous barotropic non-divergent vorticity equation on - and - planes, the method of Lie group has been applied. The method reduces the number of independent variables by one, and consequently, for the case of three independent variables we applied the method successively twice and the nonlinear partial differential equation reduces to ordinary differential equation. Investigation of exact solutions of the viscous barotropic non-divergent vorticity equation on - and - planes, via the application of Lie group, provides large classes of new exact solutions which include both Rossby and Rossby–Haurwitz waves as special cases. Also, The Lie symmetries of the viscous barotropic non-divergent vorticity equation with two parameters and , are determined. The possible reductions of the viscous barotropic vorticity equation with two parameters and have been investigated by means of one- dimensional Lie subalgebras. 相似文献
A gate-all-around charge plasma nanowire field-effect transistor (GAA CP NW FET) device using the negative-capacitance technique is introduced, termed the GAA CP NW negative-capacitance (NC) FET. In the face of bottleneck issues in nanoscale devices such as rising power dissipation, new techniques must be introduced into FET structures to overcome their major limitations. Negative capacitance is an efficient effect that can be incorporated into a device to enhance its performance for low-power applications and help to reduce the operating voltage. The Landau–Khalatnikov equation can be applied in such cases to obtain the effective bias. To determine the effects of negative capacitance, lead zirconate titanate (PZT) ferroelectric material, a ceramic material with perovskite properties, is adopted as a gate insulator. This approach diminishes the supply voltage and reduces the power dissipation in the device. Excluding their polarization properties, ferroelectric materials are similar to dielectric materials, and PZT offers abundant polarization with improved reliability and a higher dielectric capacitance. Without proper tuning of the thickness of the PZT material, hysteresis behavior mat occur. Hence, the thickness of the PZT material (tFE) is an essential parameter to optimize the device performance and achieve a reduced threshold voltage for the GAA CP NW NC-FET device proposed herein. Furthermore, varying the thickness of the PZT ferroelectric material can also enhance the performance. When using the highest values of tFE, improved outcomes with an analogously lower operating voltage are observed. The effects of varying tFE on the performance characteristics of the device including the drain current, transconductance, polarized charge, etc. are also interpreted herein.
The effectiveness of manual therapy in reducing the catabolic effects of performing repetitive intensive force tasks on bones has not been reported. We examined if manual therapy could reduce radial bone microstructural declines in adult female Sprague–Dawley rats performing a 12-week high-repetition and high-force task, with or without simultaneous manual therapy to forelimbs. Additional rats were provided 6 weeks of rest after task cessation, with or without manual therapy. The control rats were untreated or received manual therapy for 12 weeks. The untreated TASK rats showed increased catabolic indices in the radius (decreased trabecular bone volume and numbers, increased osteoclasts in these trabeculae, and mid-diaphyseal cortical bone thinning) and increased serum CTX-1, TNF-α, and muscle macrophages. In contrast, the TASK rats receiving manual therapy showed increased radial bone anabolism (increased trabecular bone volume and osteoblast numbers, decreased osteoclast numbers, and increased mid-diaphyseal total area and periosteal perimeter) and increased serum TNF-α and muscle macrophages. Rest, with or without manual therapy, improved the trabecular thickness and mid-diaphyseal cortical bone attributes but not the mineral density. Thus, preventive manual therapy reduced the net radial bone catabolism by increasing osteogenesis, while rest, with or without manual therapy, was less effective. 相似文献
The thermal stability of flip-chip solder joints made with trilayer Al/Ni(V)/Cu underbump metalization (UBM) and eutectic
Pb-Sn solder connected to substrates with either electroless Ni(P)-immersion gold (ENIG) or Pb-Sn solder on Cu pad (Cu-SOP)
surface finish was determined. The ENIG devices degraded more than 50 times faster than the Cu-SOP devices. Microstructural
characterization of these joints using scanning and transmission electron microscopy and ion beam microscopy showed that electrical
degradation of the ENIG devices was a direct result of the conversion of the as-deposited Ni(V) barrier UBM layer into a porous
fine-grained V3Sn-intermetallic compound (IMC). This conversion was driven by the Au layer in the ENIG surface finish. No such conversion
was observed for the devices assembled on Cu-SOP surface finish substrates. A resistance degradation model is proposed. The
model captures changes from a combination of phenomena including increased (1) intrinsic resistivity, (2) porosity, and (3)
electron scattering at grain boundaries and surfaces. Finally, the results from this study were compared with results found
in a number of published electromigration studies. This comparison indicates that degradation during current stressing in
the Pb-Sn bump/ENIG system is in part due to current-crowding-induced Joule heating and the thermal gradients that result
from localized Joule heating. 相似文献