Controlling magnetization reversal in Co/Pt nanostructures with perpendicular anisotropy

We demonstrate a simple method to tailor the magnetization reversal mechanisms of Co/Pt multilayers by depositing them onto large area nanoporous anodized alumina (AAO) with various aspect ratios, A = pore depth/diameter. Magnetization reversal of composite (Co/Pt)/AAO films with large A is governed by strong domain-wall pinning which gradually transforms into a rotation-dominated reversal for samples with smaller A, as investigated by a first-order reversal curve method in conjunction with analysis of the angular dependent switching fields. The change of the magnetization reversal mode is attributed to topographical changes induced by the aspect ratio of the AAO templates.Comment: 12 pages, 3 figure

Probing the A1 to L10 Transformation in FeCuPt Using the First Order Reversal Curve Method

The A1- L10 phase transformation has been investigated in (001) FeCuPt thin films prepared by atomic-scale multilayer sputtering and rapid thermal annealing (RTA). Traditional x-ray diffraction is not always applicable in generating a true order parameter, due to non-ideal crystallinity of the A1 phase. Using the first-order reversal curve (FORC) method, the A1 and L10 phases are deconvoluted into two distinct features in the FORC distribution, whose relative intensities change with the RTA temperature. The L10 ordering takes place via a nucleation-and-growth mode. A magnetization-based phase fraction is extracted, providing a quantitative measure of the L10 phase homogeneity.Comment: 17 pages, 5 figures, 4 page supplementary material (4 figures

Building a Smart E-Portfolio Platform for Optimal E-Learning Objects Acquisition

In modern education, an e-portfolio platform helps students in acquiring e-learning objects in a learning activity. Quality is an important consideration in evaluating the desirable e-learning object. Finding a means of determining a high quality e-learning object from a large number of candidate e-learning objects is an important requirement. To assist student learning in a modern e-portfolio platform, this work proposed an optimal selection approach determining a reasonable e-learning object from various candidate e-learning objects. An optimal selection approach which uses advanced information techniques is proposed. Each e-learning object undergoes a formalization process. An Information Retrieval (IR) technique extracts and analyses key concepts from the student’s previous learning contexts. A context-based utility model computes the expected utility values of various e-learning objects based on the extracted key concepts. The expected utility values of e-learning objects are used in a multicriteria decision analysis to determine the optimal selection order of the candidate e-learning objects. The main contribution of this work is the demonstration of an effective e-learning object selection method which is easy to implement within an e-portfolio platform and which makes it smarter

Magnetic Yoking and Tunable Interactions in FePt-Based Hard/Soft Bilayers

Magnetic interactions in magnetic nanostructures are critical to nanomagnetic and spintronic explorations. Here we demonstrate an extremely sensitive magnetic yoking effect and tunable interactions in FePt based hard/soft bilayers mediated by the soft layer. Below the exchange length, a thin soft layer strongly exchange couples to the perpendicular moments of the hard layer;above the exchange length, just a few nanometers thicker, the soft layer moments turn in-plane and act to yoke the dipolar fields from the adjacent hard layer perpendicular domains. The evolution from exchange to dipolar-dominated interactions is experimentally captured by first-order reversal curves, the Delta M method, and polarized neutron reflectometry, and confirmed by micromagnetic simulations. These findings demonstrate an effective yoking approach to design and control magnetic interactions in wide varieties of magnetic nanostructures and devices

Comparison of extracorporeal shock wave lithotripsy running models between outsourcing cooperation and rental cooperation conducted in Taiwan

Background/PurposeWe conducted a retrospective study to compare the cost and effectiveness between two different running models for extracorporeal shock wave lithotripsy (SWL), including the outsourcing cooperation model (OC) and the rental cooperation model (RC).MethodsBetween January 1999 and December 2005, we implemented OC for the SWL, and from January 2006 to October 2011, RC was utilized. With OC, the cooperative company provided a machine and shared a variable payment with the hospital, according to treatment sessions. With RC, the cooperative company provided a machine and received a fixed rent from the hospital. We calculated the cost of each treatment session, and evaluated the break-even point to estimate the lowest number of treatment sessions to make the balance between revenue and cost every month. Effectiveness parameters, including the stone-free rate, the retreatment rate, the rate of additional procedures and complications, were evaluated.ResultsCompared with OC there were significantly less treatment sessions for RC every month (42.6±7.8 vs. 36.8±6.5, p=0.01). The cost of each treatment session was significantly higher for OC than for RC (751.6±20.0 USD vs. 684.7±16.7 USD, p=0.01). The break-even point for the hospital was 27.5 treatment sessions/month for OC, when the hospital obtained 40% of the payment, and it could be reduced if the hospital got a greater percentage. The break-even point for the hospital was 27.3 treatment sessions/month for RC. No significant differences were noticed for the stone-free rate, the retreatment rate, the rate of additional procedures and complications.ConclusionOur study revealed that RC had a lower cost for every treatment session, and fewer treatment sessions of SWL/month than OC. The study might provide a managerial implication for healthcare organization managers, when they face a situation of high price equipment investment

New D- A- A- - Configured Small Molecule Donors Employing Conjugation to Red- shift the Absorption for Photovoltaics

Four new donor- acceptor- acceptor- (D- A- A- )- configured donors, CPNT, DCPNT, CPNBT, and DCPNBT equipped with naphtho[1,2- c:5,6- c- ²]bis([1,2,5]- thiadiazole) (NT) or naphtho[2,3- c][1,2,5]thiadiazole (NBT) as the central acceptor (A) unit bridging triarylamine donor (D) and cyano or dicyanovinylene acceptor (A- ), were synthesized and characterized. All molecules exhibit bathochromic absorption shifts as compared to those of the benzothiadiazole (BT)- based analogues owing to improved electron- withdrawing and quinoidal character of NT and NBT cores that lead to stronger intramolecular charge transfer. Favorable energy level alignments with C70, together with the good thermal stability and the antiparallel dimeric packing render CPNT and DCPNT suitable donors for vacuum- processed organic photovoltaics (OPV)s. OPVs based on DCPNT- :- C70 active layers displayed the best power conversion efficiency (PCE)=8.3%, along with an open circuit voltage of 0.92- V, a short circuit current of 14.5- mA- cm- 2 and a fill factor of 62% under 1 sun intensity, simulated AM1.5G illumination. Importantly, continuous light- soaking with AM 1.5G illumination has verified the durability of the devices based on CPNT:C70 and DCPNT- :- C70 as the active blends. The devices were examined for their feasibility of indoor light harvesting under 500 lux illumination by a TLD- 840 fluorescent lamp, giving PCE=12.8% and 12.6%, respectively. These results indicate that the NT- based D- A- A- - type donors CPNT and DCPNT are potential candidates for high- stability vacuum- processed OPVs suitable for indoor energy harvesting.New donor- acceptor- acceptor- (D- A- A- )- configured small molecule donors with extended Ï - conjugation for red- shifting the absorption were characterized. The OPV comprising the donor DCPNT bearing naphtho[1,2- c:5,6- c- ²]bis([1,2,5]- thiadiazole) (NT) as A, cyano as A- , and acceptor C70 displayed the power conversion efficiency of 8.3% under AM 1.5G and 12.8% under 500 lux of TLD- 840 lamp, indicating the potential for indoor photovoltaics application.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/156487/3/asia202000635.pdfhttp://deepblue.lib.umich.edu/bitstream/2027.42/156487/2/asia202000635-sup-0001-misc_information.pdfhttp://deepblue.lib.umich.edu/bitstream/2027.42/156487/1/asia202000635_am.pd