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31.
Jibo Qin Yibo Dou Jianchi Zhou Victor M. Candelario Henrik Rasmus Andersen Claus Hélix-Nielsen Wenjing Zhang 《Advanced functional materials》2023,33(28):2214839
The conversion of waste plastic into high-value-added chemicals is regarded as a promising approach for relieving global plastic pollution and contributing to the circular economy. Herein, a partial calcination strategy is developed to fabricate a zinc oxide/UiO66-NH2 (ZnO/UiO66-NH2) heterojunction, in which ZnO is encapsulated in porous UiO66-NH2 for the photocatalytic valorization of plastic. This strategy preserves the framework structure of UiO66-NH2, thus enabling the formation of ZnO with ultra-small size distributed inside the skeleton. The synergistic effect of the obtained ZnO/UiO66-NH2 heterojunction facilitates providing an efficient channel for carrier/mass transfer and guarantees structural stability. As a result, ZnO/UiO66-NH2 exhibits high activity for converting polylactic acid (PLA) and polyvinyl chloride (PVC) into acetic acid, coupled with H2 production. This work provides a feasible strategy for rationally designing heterojunction photocatalysts, as well as an insight into understanding the process of photocatalytic valorization of plastic. 相似文献
32.
Yong Ryun Kim Oskar J. Sandberg Stefan Zeiske Gregory Burwell Drew B. Riley Paul Meredith Ardalan Armin 《Advanced functional materials》2023,33(16):2300147
Poly(3,4-ethylenedioxythiophene):polystyrene sulfonate (PEDOT:PSS) has been one of the most established hole transport layers (HTL) in organic solar cells (OSCs) for several decades. However, the presence of PSS− ions is known to deteriorate device performance via a number of mechanisms including diffusion to the HTL-active layer interface and unwanted local chemical reactions. In this study, it is shown that PSS− ions can also result in local p-doping in the high efficiency donor:non-fullerene acceptor blends – resulting in photocurrent loss. To address these issues, a facile and effective approach is reported to improve the OSC performance through a two-component hole transport layer (HTL) consisting of a self-assembled monolayer of 2PACz ([2-(9H-Carbazol-9-yl)ethyl]phosphonic acid) and PEDOT:PSS. The power conversion efficiency (PCE) of 17.1% using devices with PEDOT:PSS HTL improved to 17.7% when the PEDOT:PSS/2PACz two-component HTL is used. The improved performance is attributed to the overlaid 2PACz layer preventing the formation of an intermixed p-doped PSS− ion rich region (≈5–10 nm) at the bulk heterojunction-HTL contact interface, resulting in decreased recombination losses and improved stability. Moreover, the 2PACz monolayer is also found to reduce electrical shunts that ultimately yield improved performance in large area devices with PCE enhanced from 12.3% to 13.3% in 1 cm2 cells. 相似文献
33.
MR Harrison GB Mychaliska CT Albanese RW Jennings JA Farrell S Hawgood P Sandberg AH Levine E Lobo RA Filly 《Canadian Metallurgical Quarterly》1998,33(7):1017-22; discussion 1022-3
BACKGROUND/PURPOSE: Fetuses with congenital diaphragmatic hernia (CDH) who have a "poor prognosis" with postnatal treatment now can be identified on the basis of liver herniation, early diagnosis (before 25 weeks' gestation) and a low lung-to-head ratio (LHR). Because complete in utero repair proved unsuccessful for this group, the strategy of temporary tracheal occlusion was developed to gradually enlarge the hypoplastic fetal lung. The purpose of this study is to compare the outcome of patients in the poor-prognosis group treated by one of three methods: (1) standard postnatal care, (2) fetal tracheal occlusion via open hysterotomy, and (3) the recently developed video-fetoscopic (Fetendo) technique of tracheal occlusion without hysterotomy. METHODS: In the past 3 years, 34 of 86 fetuses with an isolated left CDH met criteria for the poor-prognosis group. Thirteen families chose postnatal treatment at an extracorporeal membrane oxygenation (ECMO) center, 13 underwent open fetal tracheal occlusion, and eight underwent fetoscopic tracheal occlusion. RESULTS: The survival rate was 38% in the group treated by standard postnatal therapy, 15% in the open tracheal occlusion group, and 75% in the Fetendo group. There were less postoperative pulmonary complications noted in mothers who underwent the Fetendo procedure versus the open tracheal occlusion. All but one Fetendo clip patient had a striking physiological response demonstrated by sonographic enlargement of the small left lung that was documented postnatally by plain radiographs and its subjective appearance during repair of the CDH. In contrast, only 5 of the 13 open tracheal occlusion patients demonstrated lung growth. CONCLUSION: Fetuses with a left CDH who have liver herniation and a low LHR are at high risk of neonatal demise and appear to benefit from temporary tracheal occlusion when performed fetoscopically, but not when performed by open fetal surgery. 相似文献
34.
Tao Dong Zhaochu Yang Qianhua Su Nhut Minh Tran Eirik Bentzen Egeland Frank Karlsen Yulong Zhang Matteo Joseph Kapiris Henrik Jakobsen 《Microfluidics and nanofluidics》2011,10(4):855-865
This study addresses the need to reduce the risk of clogging when preparing samples for cell concentration, i.e., the CaSki
Cell-lines (epidermoid cervical carcinoma cells). Aiming to develop a non-clogging microconcentrator, we proposed a new counter-flow
concentration unit characterized by the directions of penetrating flows being at an obtuse angle to the main flow, due to
employment of streamlined turbine blade-like micropillars. Based on the optimization results of the counter-flow unit profile,
a fractal arrangement for the counter-flow concentration unit was developed. A counter-flow microconcentrator chip was then
designed and fabricated, with both the processing layer and collecting layer arranged in terms of the honeycomb structure.
Visualized experiments using CaSki cell samples on the microconcentrator chip demonstrated that no cell-clogging phenomena
occurred during the test and that no cells were found in the final filtrate. The test results show an excellent concentration
performance for the microconcentrator chip, while a concentrating ratio of >4 with the flow rate being below 1.0 ml/min. As
only geometrical structure is employed in the passive device, the counter-flow microconcentrator can be easily integrated
into advanced microfluidic systems. Owing to the merit of non-clogging and continuous processing ability, the counter-flow
microconcentrator is not only suitable for the sample preparation within biomedical field, but also applicable in water-particle
separation. 相似文献
35.
Henrik Bærbak Christensen Author Vitae Klaus Marius Hansen Author Vitae 《Journal of Systems and Software》2010,83(1):133-142
Architectural prototyping is the process of using executable code to investigate stakeholders’ software architecture concerns with respect to a system under development. Previous work has established this as a useful and cost-effective way of exploration and learning of the design space of a system and in addressing issues regarding quality attributes, architectural risks, and the problem of knowledge transfer and conformance. However, the actual industrial use of architectural prototyping has not been thoroughly researched so far. In this article, we report from three studies of architectural prototyping in practice. First, we report findings from an ethnographic study of practicing software architects. Secondly, we report from a focus group on architectural prototyping involving architects from four companies. And, thirdly, we report from a survey study of 20 practicing software architects and software developers. Our findings indicate that architectural prototyping plays an important and frequent role in resolving problems experimentally, but less so in exploring alternative solutions. Furthermore, architectural prototypes include end-user or business related functionality rather than purely architectural functionality. Based on these observations we provide recommendations for effective industrial architectural prototyping. 相似文献
36.
With motivation from considerations in XML database theory and model checking, data strings have been introduced as an extension of finite alphabet strings which carry, at each position, a symbol and a data value from an infinite domain. Previous work has shown that it is difficult to come up with an expressive yet decidable automaton model for data languages. Recently, such a model, data automata, was introduced. This paper introduces a simpler but equivalent model and investigates its expressive power, algorithmic and closure properties, and some extensions. 相似文献
37.
Simon Schütz Henrik Abrahamsson Bengt Ahlgren Marcus Brunner 《Computer Networks》2010,54(7):1142-1154
The Internet Protocol (IP) has been proven very flexible, being able to accommodate all kinds of link technologies and supporting a broad range of applications. The basic principles of the original Internet architecture include end-to-end addressing, global routeability and a single namespace of IP addresses that unintentionally serves both as locators and host identifiers. The commercial success and widespread use of the Internet have lead to new requirements, which include Internetworking over business boundaries, mobility and multi-homing in an untrusted environment. Our approach to satisfy these new requirements is to introduce a new Internetworking layer, the node identity layer. Such a layer runs on top of the different versions of IP, but could also run directly on top of other kinds of network technologies, such as MPLS and 2G/3G PDP contexts. This approach enables connectivity across different communication technologies, supports mobility, multi-homing, and security from ground up. This paper describes the Node Identity Architecture in detail and discusses the experiences from implementing and running a prototype. 相似文献
38.
Bin Xiao Tao Dong Einar Halvorsen Zhaochu Yang Yulong Zhang Nils Hoivik Dandan Gu Nhut Minh Tran Henrik Jakobsen 《Microsystem Technologies》2011,17(1):115-125
This paper presents the design and fabrication of a micro Pirani gauge using VO
x
as the sensitive material for monitoring the pressure inside a hermetical package for micro bolometer focal plane arrays
(FPAs). The designed Pirani gauge working in heat dissipating mode was intentionally fabricated using standard MEMS processing
which is highly compatible with the FPAs fabrication. The functional layer of the micro Pirani gauge is a VO
x
thin film designed as a 100 × 200 μm pixel, suspended 2 μm above the substrate. By modeling of rarefied gas heat conduction
using the Extended Fourier’s law, finite element analysis is used to investigate the sensitivity of the pressure gauge. Also
the thermal interactions between the micro Pirani gauge and bolometer FPAs are verified. From the fabricated prototype, the
measured device TCR is about −0.8% K−1 and the sensitivity about 1.84 × 10−3 W K−1 mbar−1. 相似文献
39.
A boundary value problem for the KdV equation: Comparison of finite-difference and Chebyshev methods
Solutions of a boundary value problem for the Korteweg–de Vries equation are approximated numerically using a finite-difference method, and a collocation method based on Chebyshev polynomials. The performance of the two methods is compared using exact solutions that are exponentially small at the boundaries. The Chebyshev method is found to be more efficient. 相似文献
40.
This paper develops and tests a motivational model to explain the overall continuance intention to use computers and smartphones. Based on survey data from 192 undergraduate students, structural equation modeling analysis is used to report: (1) the independent effect of intrinsic motivation on the continuance intention to use computers and smartphones; (2) the independent effect of extrinsic motivation on the continuance intention to use computers but not smartphones; (3) intrinsic motivation mediating the effect of extrinsic motivation on the continuance intention to use computers; (4) the independent effect of technology cognizance on the continuance intention to use computers but not smartphones; (5) intrinsic motivation positively influencing extrinsic motivation and technology cognizance, with respect to both devices. This research contributes to an improved understanding of the independent and interrelated effects of intrinsic and extrinsic motivations to use technological devices. The findings have important implications for theory and practice regarding the overall use of technology. 相似文献