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971.
972.
973.
磁共振图像的重建、后处理及可视化是磁共振成像(MRI)系统的重要组成部分.本文开发了一个新的用于磁共振图像重建、后处理及可视化的开源框架YAP(Yet Another Pipeline),利用此框架可以方便地构建图像处理流水线.与现有的一些其他开源框架相比,本文开发的框架具有如下特点:(1)采用基于接口的设计,可使用基于接口的插件对流水线的功能进行扩展;(2)允许用户使用编写脚本的方式构建图像处理流水线,编辑与修改流水线都很方便;(3)支持带有分支结构的流水线,便于流水线的构建与调试.目前,该框架已经在商用系统中获得了应用. 相似文献
974.
Cheng Wang Qing N. Chan Renlin Zhang Sanghoon Kook Evatt R. Hawkes Guan H. Yeoh Paul R. Medwell 《Journal of nanoparticle research》2016,18(5):127
The thermophoretic sampling of particulates from hot media, coupled with transmission electron microscope (TEM) imaging, is a combined approach that is widely used to derive morphological information. The identification and the measurement of the particulates, however, can be complex when the TEM images are of low contrast, noisy, and have non-uniform background signal level. The image processing method can also be challenging and time consuming, when the samples collected have large variability in shape and size, or have some degree of overlapping. In this work, a three-stage image processing sequence is presented to facilitate time-efficient automated identification and measurement of particulates from the TEM grids. The proposed processing sequence is first applied to soot samples that were thermophoretically sampled from a laminar non-premixed ethylene-air flame. The parameter values that are required to be set to facilitate the automated process are identified, and sensitivity of the results to these parameters is assessed. The same analysis process is also applied to soot samples that were acquired from an externally irradiated laminar non-premixed ethylene-air flame, which have different geometrical characteristics, to assess the morphological dependence of the proposed image processing sequence. Using the optimized parameter values, statistical assessments of the automated results reveal that the largest discrepancies that are associated with the estimated values of primary particle diameter, fractal dimension, and prefactor values of the aggregates for the tested cases, are approximately 3, 1, and 10 %, respectively, when compared with the manual measurements. 相似文献
975.
976.
Zhang Luyuan Hou Xiaolin Cheng Peng Chen Ning Fan Yukun Liu Qi 《Journal of Radioanalytical and Nuclear Chemistry》2018,316(1):383-388
Journal of Radioanalytical and Nuclear Chemistry - Environmental impact of North Korea nuclear weapons testing on 3 Sept, 2017, is of key concern. In order to investigate whether there is... 相似文献
977.
Tianrui Zhao Mengxue Sun Lingpeng Kong Qingwang Xue Yudan Wang Yifen Wang Afsar Khan Jianxin Cao Guiguang Cheng 《Molecules (Basel, Switzerland)》2021,26(7)
Vaccinium dunalianum Wight, usually processed as a traditional folk tea beverage, is widely distributed in the southwest of China. The present study aimed to investigate the antioxidant, α-glucosidase and pancreatic lipase inhibitory activities of V. dunalianum extract and isolate the bioactive components. In this study, the crude extract (CE) from the buds of V. dunalianum was prepared by the ultrasound-assisted extraction method in 70% methanol and then purified with macroporous resin D101 to obtain the purified extract (PM). Five fractions (Fr. A–E) were further obtained by MPLC column (RP-C18). Bioactivity assays revealed that Fr. B with 40% methanol and Fr. D with 80% methanol had better antioxidant with 0.48 ± 0.03 and 0.62 ± 0.01 nM Trolox equivalent (TE)/mg extract for DPPH, 0.87 ± 0.02 and 1.58 ± 0.02 nM TE/mg extract for FRAP, 14.42 ± 0.41 and 19.25 ± 0.23 nM TE/mg extract for ABTS, and enzyme inhibitory effects with IC50 values of 95.21 ± 2.21 and 74.55 ± 3.85 for α-glucosidase, and 142.53 ± 11.45 and 128.76 ± 13.85 µg/mL for pancreatic lipase. Multivariate analysis indicated that the TPC and TFC were positively related to the antioxidant activities. Further phytochemical purification led to the isolation of ten compounds (1–10). 6-O-Caffeoylarbutin (7) showed significant inhibitory effects on α-glucosidase and pancreatic lipase enzymes with values of 38.38 ± 1.84 and 97.56 ± 7.53 µg/mL, and had the highest antioxidant capacity compared to the other compounds. 相似文献
978.
Thermal analysis and hazards evaluation for HTP-65W through calorimetric technologies and simulation
Wang Yan-Ru Liu Shang-Hao Cheng Yen-Chun 《Journal of Thermal Analysis and Calorimetry》2021,144(4):1483-1492
Journal of Thermal Analysis and Calorimetry - Di-tert-butyl peroxy-hexahydro terephthalate (HTP-65W), a newly developed organic peroxide, has been used in manufacturing... 相似文献
979.
Designs, Codes and Cryptography - The Learning-With-Errors (LWE) problem (and its variants including Ring-LWE and Module-LWE), whose security are based on hard ideal lattice problems, has proven to... 相似文献
980.
Bo Wang Dr. Wencheng Du Dr. Yang Yang Dr. Yufei Zhang Dr. Qi Zhang Prof. Xianhong Rui Dr. Hongbo Geng Prof. Cheng Chao Li 《Chemistry (Weinheim an der Bergstrasse, Germany)》2020,26(29):6554-6560
Lithium ion batteries (LIBs) at present still suffer from low rate capability and poor cycle life during fast ion insertion/extraction processes. Searching for high-capacity and stable anode materials is still an ongoing challenge. Herein, a facile strategy for the synthesis of ultrathin GeS2 nanosheets with the thickness of 1.1 nm is reported. When used as anodes for LIBs, the two-dimensional (2D) structure can effectively increase the electrode/electrolyte interface area, facilitate the ion transport, and buffer the volume expansion. Benefiting from these merits, the as-synthesized GeS2 nanosheets deliver high specific capacity (1335 mAh g−1 at 0.15 A g−1), extraordinary rate performance (337 mAh g−1 at 15 A g−1) and stable cycling performance (974 mAh g−1 after 200 cycles at 0.5 A g−1). Importantly, our fabricated Li-ion full cells manifest an impressive specific capacity of 577 mAh g−1 after 50 cycles at 0.1 A g−1 and a high energy density of 361 Wh kg−1 at a power density of 346 W kg−1. Furthermore, the electrochemical reaction mechanism is investigated by the means of ex-situ high-resolution transmission electron microscopy. These results suggest that GeS2 can use to be an alternative anode material and encourage more efforts to develop other high-performance LIBs anodes. 相似文献