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排序方式: 共有6139条查询结果,搜索用时 15 毫秒
81.
Shaghayegh Naghdi Emily Brown Mohammad Zendehbad Ann Duong Wolfgang Ipsmiller Santu Biswas Maytal Caspary Toroker Hossein Kazemian Dominik Eder 《Advanced functional materials》2023,33(20):2213862
The selective removal of one ligand in mixed-ligand MOFs upon thermolysis provides a powerful strategy to introduce additional mesopores without affecting the overall MOF structure. By varying the initial ligand ratio, MOFs of the MIL-125-Ti family with two distinct hierarchical pore architectures are synthesized, resembling either large cavities or branching fractures. The performance of the resulting hierarchically porous MOFs is evaluated toward the adsorptive removal of glyphosate (N-(phosphonomethyl)glycine) from water, and the adsorption kinetics and mechanism are examined. Due to their strong affinity for phosphoric groups, the numerous Ti–OH groups resulting from the selective ligand removal act as natural anchor points for effective glyphosate uptake. The relationships between contact duration, glyphosate concentration, and adsorbent dosage are investigated, and the impact of these parameters on the effectiveness of glyphosate removal from contaminated water samples is examined. The introduction of additional mesopores has increased the adsorption capacities by nearly 3 times with record values exceeding 440.9 mg g−1, which ranks these MOFs among the best-reported adsorbents. 相似文献
82.
Using full 3D TCAD, an evaluation of process parameter space of bulk FinFET is presented from the point of view of DRAM, SRAM and I/O applications. Process and device simulations are performed with varying uniform fin doping, anti-punch implant dose and energy, fin width, fin height and gate oxide thickness. Bulk FinFET architecture with anti-punch implant is introduced beneath the channel region to reduce the punch-through and junction leakage. For 30 nm bulk FinFET, anti-punch implant with low energy of 15 to 25 keV and dose of 5.0 × 1013 to 1.0 × 1014 cm−2 is beneficial to effectively suppress the punch-through leakage with reduced GIDL and short channel effects. Our simulations show that bulk FinFETs are approximately independent of back bias effect. With identical fin geometry, bulk FinFETs with anti-punch implant show same ION-IOFF behavior and approximately equal short channel effects like SOI FinFETs. 相似文献
83.
Ulrich Glaser Kai Esmark Martin Streibl Christian Russ Krzysztof Domaski Mauro Ciappa Wolfgang Fichtner 《Microelectronics Reliability》2007,47(7):1044-1053
Diodes and diode strings in 90 nm and beyond technologies are investigated by measurement and device simulation. After a thorough calibration, the device simulator is utilised to achieve a better understanding and an enhanced device performance of diode strings under static and transient ESD conditions. Thereto, parasitic transistors and a so far neglected parasitic thyristor (SCR) in the diode string are regarded, exploited and optimised. 相似文献
84.
Diana Nanova Sebastian Beck Andreas Fuchs Tobias Glaser Christian Lennartz Wolfgang Kowalsky Annemarie Pucci Michael Kroeger 《Organic Electronics》2012,13(7):1237-1244
The degree of charge transfer in thin films of organic charge transfer (CT)-complexes, which are deposited via thermal evaporation, is examined via infrared-spectroscopy. We demonstrate a linear relationship between the shift in the excitation energy of the CN-stretching mode of CT-complexes with the acceptor 7,7,8,8-tetracyanoquinodimethane (TCNQ) and the charge transfer. The measured correlation corresponds very well with DFT calculations. For Na-TCNQ we observe a splitting in the peak of the CN-stretching mode, which can be explained by the coupling of two modes and was confirmed by the calculations. In CT-complexes with partial charge transfer the appearance of an electronic excitation is demonstrated. 相似文献
85.
6.2号筒压缩式驱动器(单元)
这是一个用酚醛树脂含浸的织物为振膜的号筒压缩式单元,音圈直径51nm,卷线高度4.6mm,气隙厚4mm。连接的号筒和相位塞被移走,后腔体积仔细地密封好以避免任何额外的声学共振。 相似文献
86.
David C. Trimbach Brandis Keller Rahila Bhat Sergiy Zankovych Rüdiger Pöhlmann Siegmund Schröter Jörg Bossert Klaus D. Jandt 《Advanced functional materials》2008,18(12):1723-1731
As an alternative to expensive extracellular matrix (ECM) proteins generally applied as coatings in Petri dishes used for cell binding, an innovative system based on epoxide‐functionalized monolayers capable of protein binding is proposed. Since cells bind to material surfaces through proteins, protein‐binding surfaces should also promote cell binding. Here we investigate how the cell‐binding properties of an epoxide‐functionalized surface compares with ECM protein gel coated surfaces and tissue culture polystyrene control surfaces. Glass surfaces are functionalized with glycidoxypropyltriethoxysilane (GOPS), which results in an epoxide‐functionalized surface capable of binding proteins through an epoxide–amine reaction. Advancing contact angle measurements and atomic force microscopy measurements confirm the formation of a homogeneous GOPS monolayer. This monolayer is micropatterned with fluorescein‐labeled ECM protein gel by microcontact printing (µCP). Confocal laser scanning microscopy (CLSM) shows accurately transferred ECM protein gel micropatterns. Osteoblasts that are seeded on these micropatterned substrates show a clear preference for adhering to the epoxide‐functionalized areas. The morphology of these cultured osteoblasts is needle‐like with high aspect ratios. As controls, osteoblasts are cultured on GOPS‐functionalized surfaces, unstructured ECM protein gel surfaces, and tissue culture polystyrene (TCPS). The GOPS surfaces demonstrate a drastic increase in cell adhesion after 2 h, whilst the other tests show no adverse effects of this surface on the osteoblasts as compared to ECM and TCPS. CLSM shows healthy cell morphologies on each surface. It is demonstrated for the first time that epoxide groups outperform ECM protein gel in cell adhesion, thereby providing new routes for cost‐effective coatings that improve biocompatibility as well as exciting, new methodologies to control and direct cell adhesion. 相似文献
87.
Hartmut Bartelt Wolfgang Ecke Reinhardt Willsch Jens Kobelke Michael Kautz Sven Brueckner Manfred Rothhardt 《中国电子科技》2008,6(4):429-433
This paper reports fiber Bragg gratings (FBGs) inscribed in a small-core Ge-doped photonic crystal fibers with a UV laser and a Talbot interferometer. The responses of such FBGs to temper- ature, strain, bending, and transverse-loading were systematically investigated. The Bragg wavelength of the FBGs shifts toward longer wavelengths with increasing temperature, tensile strain, and transverse-loading. The bending and transverse- loading properties of the FBGs are sensitive to the fiber orientations. 相似文献
88.
Dirty RF: A New Paradigm 总被引:1,自引:0,他引:1
Gerhard Fettweis Michael Löhning Denis Petrovic Marcus Windisch Peter Zillmann Wolfgang Rave 《International Journal of Wireless Information Networks》2007,14(2):133-148
The implementation challenge for new low-cost low-power wireless modem transceivers has continuously been growing with increased
modem performance, bandwidth, and carrier frequency. Up to now we have been designing transceivers in a way that we are able
to keep the analog (RF) problem domain widely separated from the digital signal processing design. However, with today’s deep
sub-micron technology, analog impairments – “dirt effects” – are reaching a new problem level which requires a paradigm shift
in the design of transceivers. Examples of these impairments are phase noise, non-linearities, I/Q imbalance, ADC impairments,
etc. In the world of “Dirty RF” we assume to design digital signal processing such that we can cope with a new level of impairments,
allowing lee-way in the requirements set on future RF sub-systems. This paper gives an overview of the topic and presents
analytical evaluations of the performance losses due to RF impairments as well as algorithms that allow to live with imperfect
RF by compensating the resulting error effects using digital baseband processing. 相似文献
89.
Peter Kuczynski Arnaud Rigoll Wolfgang H. Gerstacker Johannes B. Huber 《AEUE-International Journal of Electronics and Communications》2004,58(4):256-267
In this paper, a Hidden Markov Modeling (HMM) technique for a fast and accurate simulation of bit errors and soft outputs in wireless communication systems is presented. HMMs with continuous probability distributions are considered. Soft outputs and bit errors are combined to error patterns. We focus on binary phase–shift keying (BPSK) modulation for direct–sequence spread spectrum (code–division multiple access, CDMA) transmission as proposed e.g. for the third generation wireless communication system UMTS (uplink for the frequency division duplex mode (FDD)). Comparisons of simulated bit error rates for HMM models and Rake receivers are shown for AWGN, flat fading, and vehicular channel conditions. In order to assess the ability of the HMM to describe the dynamical behaviour of the channel a comparison for transmission with interleaving and convolutional coding is presented. Furthermore calculated autocorrelation functions of the error patterns and error gap distributions corresponding to the Rake receiver and to the HMM, respectively, are presented. Our investigations show a strong dependence of the required HMM order on Eb/N0 and the channel conditions. The degree of accordance of the HMM outputs and the training data is examined based on calculated statistical scoring indicators. 相似文献
90.
In this work we compare the performance of Scanning Capacitance Microscopy and Scanning Spreading Resistance Microscopy for the characterization of doping profiles in semiconductor devices. Particular attention is devoted to parameters of paramount importance for the failure analysis and the characterization of silicon devices, like the quantitative one-dimensional profiling accuracy, the electrical junction delineation and the two-dimensional sub-micron imaging capability. 相似文献