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1.
Timothy Zurrer Kenneth Wong Jonathan Horlyck Emma C. Lovell Joshua Wright Nicholas M. Bedford Zhaojun Han Kang Liang Jason Scott Rose Amal 《Advanced functional materials》2021,31(9):2007624
The vast chemical and structural tunability of metal–organic frameworks (MOFs) are beginning to be harnessed as functional supports for catalytic nanoparticles spanning a range of applications. However, a lack of straightforward methods for producing nanoparticle-encapsulated MOFs as efficient heterogeneous catalysts limits their usage. Herein, a mixed-metal MOF, NiMg-MOF-74, is utilized as a template to disperse small Ni nanoclusters throughout the parent MOF. By exploiting the difference in Ni O and Mg O coordination bond strength, Ni2+ is selectively reduced to form highly dispersed Ni nanoclusters constrained by the parent MOF pore diameter, while Mg2+ remains coordinated in the framework. By varying the ratio of Ni to Mg in the parent MOF, accessible surface area and crystallinity can be tuned upon thermal treatment, influencing CO2 adsorption capacity and hydrogenation selectivity. The resulting Ni nanoclusters prove to be an active catalyst for CO2 methanation and are examined using extended X-ray absorption fine structure and X-ray photoelectron spectroscopy. By preserving a segment of the Mg2+-containing MOF framework, the composite system retains a portion of its CO2 adsorption capacity while continuing to deliver catalytic activity. The approach is thus critical for designing materials that can bridge the gap between carbon capture and CO2 utilization. 相似文献
2.
H. L. Du S. R. Rose Z. D. Xiang P. K. Datta X. Y. Li 《Materialwissenschaft und Werkstofftechnik》2003,34(4):421-426
The oxidation/sulphidation behaviour of a Ti‐46.7Al‐1.9W‐0.5Si alloy with a TiAl3 diffusion coating was studied in an environment of H2/H2S/H2O at 850oC. The kinetic results demonstrate that the TiAl3 coating significantly increased the high temperature corrosion resistance of Ti‐46.7Al‐1.9W‐0.5Si. The SEM, EDX, XRD and TEM analysis reveals that the formation of an Al2O3 scale on the surface of the TiAl3‐coated sample was responsible for the enhancement of the corroison resistance. The Ti‐46.7Al‐1.9W‐0.5Si alloy was also modified by Nb ion implantation. The Nb ion implanted and as received sampels were subjected to cyclic oxidation in an open air at 800oC. The Nb ion implantation not only increased the oxidation resistance but also substantially improved the adhesion of scale to the substrate. 相似文献
3.
This paper describes the implementation of a stereo-vision system using Field Programmable Gate Arrays (FPGAs). Reconfigurable hardware, including FPGAs, is an attractive platform for implementing vision algorithms due to its ability to exploit parallelism often found in these algorithms, and due to the speed with which applications can be developed as compared to hardware. The system outputs 8-bit, subpixel disparity estimates for 256× 360 pixel images at 30,fps. A local-weighted phase correlation algorithm for stereo disparity [Fleet, D. J.: {Int. Conf. Syst. Man Cybernetics 1:48–54 (1994)] is implemented. Despite the complexity of performing correlations on multiscale, multiorientation phase data, the system runs as much as 300 times faster in hardware than its software implementation. This paper describes the hardware platform used, the algorithm, and the issues encountered during its hardware implementation. Of particular interest is the implementation of multiscale, steerable filters, which are widely used in computer vision algorithms. Several trade-offs (reducing the number of filter orientations from three to two, using fixed-point computation, changing the location of one localized low-pass filter, and using L1 instead of L2 norms) were required to both fit the design into the available hardware and to achieve video-rate processing. Finally, results from the system are given both for synthetic data sets as well as several standard stereo-pair test images. 相似文献
4.
A review of Distributed Infrastructure Support for Electronic Commerce Applications by Hans-Arno Jacobsen. 相似文献
5.
6.
C Diamond ML Huang DH Kedes C Speck GW Rankin D Ganem RW Coombs TM Rose JN Krieger L Corey 《Canadian Metallurgical Quarterly》1997,176(3):775-777
The prevalence of human herpesvirus 8 (HHV-8)/Kaposi's sarcoma (KS)-associated herpesvirus was investigated in the semen of 99 human immunodeficiency virus (HIV)-infected men (median CD4 cell count, 357/mm3) by use of a polymerase chain reaction (PCR) assay capable of detecting <10 copies of HHV-8 DNA. Of the subjects, 95 (96%) self-identified as men who have sex with men (MSM), and 3 had a history of clinical KS. Seminal cell specimens were negative for HHV-8 in 98 subjects. None of the 26 without KS (27.1% of 96 tested) who were seropositive for HHV-8 by IFA for latency-associated nuclear antigens had HHV-8 detected in their semen. The only subject with any evidence for seminal HHV-8 DNA was seropositive for HHV-8 and had active KS. HHV-8 was detected in 10 (10.4%) of 96 peripheral blood mononuclear cell specimens. The prevalence of HHV-8 DNA by PCR in semen of HIV-infected MSM without KS is low. 相似文献
7.
We discovered that a food aversion could be conditioned in anesthetized sheep. Sheep were allowed to eat a familiar food (alfalfa-grain pellets) for 30 min, and 90 min later they were given either an intraruminal (IR) injection of water (C), an IR injection of LiCl (L), anesthesia followed by an IR injection of water (A), or anesthesia followed by an IR injection of LiCl (A+L). Induction of anesthesia was by an intravenous injection of pentobarbitone sodium, and maintenance of deep anesthesia was by halothane. Sheep were maintained in deep anesthesia for 2 h to ensure that the effects of LiCl on the acquisition of a food aversion, which occur within about 1 h, were completed before they awakened. When tested 5 days later, sheep that received LiCl (treatments L and A+L) consumed less alfalfa-grain pellets than sheep that did not receive LiCl (treatments C and A) (241 g vs. 306 g; p = 0.057). Intake of sheep that were anesthetized (treatments A and A+L) did not differ from that of sheep that were not anesthetized (treatments C and L) (295 g vs. 252 g; p = 0.183). Nor was there an interaction between LiCl and anesthesia (p = 0.423). Thus, we conclude that changes in preferences for foods caused by postingestive feedback occur automatically every time food is ingested (i.e., they are noncognitive), and the kind and amount of feedback is a function of the match between the food's chemical characteristics and its ability to meet the animal's current demands for nutrients. 相似文献
8.
FD Fuchs 《Canadian Metallurgical Quarterly》1996,67(4):267-269
We have treated 50 patients with stage III, VI malignant tumors confirmed by pathology. The patients were divided into two groups. One group was treated by combination of chemotherapy and traditional Chinese medicine (treatment group); the other only by chemotherapy (control group). The effect of cancer treatment was evaluated according to the criteria of WHO. The results showed that the effective rate was 80% in treatment group and 52% in control group. The pain relieving rate was 68% in treatment group and 40% in control group (P < 0.01). This fact demonstrates that the application of traditional Chinese medicine can invigorate blood circulation, eliminate blood stasis, soften hardness and dissolve the mass, nourish blood and increase vigor. This kind of application can not only enhance the effect of cancer treatment but also increase the cancer pain relieving rate. 相似文献
9.
Lewis D.M. Galloway D.R. Van Ierssel M. Rose J. Chow P. 《Very Large Scale Integration (VLSI) Systems, IEEE Transactions on》1998,6(2):188-198
This paper describes the Transmogrifier-2 (TM-2), a second-generation multifield programmable gate array (FPGA) rapid-prototyping system. The largest version of the system will comprise 16 boards that each contain two Altera 10K50 FPGA's, four I-Cube interconnect chips, and up to 8 Mbytes of memory. The inter-FPGA routing architecture of the TM-2 uses a novel interconnect structure, a nonuniform partial crossbar, that provides a constant delay between any two FPGA's in the system. The TM-2 architecture is modular and scalable, meaning that systems of various sizes can be constructed from copies of the same board, while maintaining routability and the constant delay feature. Other features include a system-level programmable clock that allows single-cycle access to off-chip memory, and programmable clock waveforms with edge resolution of 10 ns. The first Transmogrifier-2 boards have been manufactured and are functional. They have recently been used successfully in some simple graphics acceleration applications 相似文献
10.
AK Souid MC Ziemba AS Dubansky M Mazur M Oliphant FD Thomas M Ratner PD Sadowitz 《Canadian Metallurgical Quarterly》1993,72(6):2042-2048
The authors presented the cases of two children with inflammatory myofibroblastic (IMF) tumor and reviewed the literature to facilitate the preoperative recognition, delineate the clinical features, and describe the natural history of this entity. The first child had IMF tumor arising from the mesentery of the small intestine. He presented with an abdominal mass associated with severe inflammatory response manifested by fever, impaired growth, thrombocytosis, and microcytic, hypochromic anemia. After surgical resection, his fever resolved and his growth rate and the laboratory abnormalities normalized. Five months after initial diagnosis, the fever, anemia, and thrombocytosis recurred along with two tumors arising from the omentum and the abdominal soft tissue. After the second surgery, he remains free of recurrent disease for 30 months. The second child presented with a lung mass that was radiologically indistinguishable from pulmonary sequestration. After surgical resection, she remains free of recurrent disease for 18 months. IMF tumor should be considered in any solid tumor that occurs in association with a chronic inflammatory response. IMF tumor should also be considered in the differential diagnosis of pulmonary sequestration. 相似文献