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71.
Nolte Steffen Fink Reinhard Krooss Bernhard M. Amann-Hildenbrand Alexandra Wang Yue Wang Moran Schmatz Joyce Klaver Jop Littke Ralf 《Transport in Porous Media》2021,137(3):519-553
Transport in Porous Media - To improve the understanding of gas transport processes in tight rocks (e.g., shales), systematic flow tests with different gases were conducted on artificial micro- to... 相似文献
72.
Lin Miao-Miao Xue Ding-Wei Wang Yue Zhang Ke-Jia 《International Journal of Theoretical Physics》2021,60(4):1237-1245
International Journal of Theoretical Physics - In this paper, a quantum payment protocol based on a special set of local indistinguishable orthogonal product states (X-LIOP) is proposed. In the... 相似文献
73.
Peng Yang Yaxin Sun Kaiyue Fu Li Zhang Guang Yang Jieyu Yue Yu Ma Jianrong Steve Zhou Bo Tang 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2022,134(1):e202111778
We report a stereoselective conversion of terminal alkynes to α-chiral carboxylic acids using a nickel-catalyzed domino hydrocarboxylation-transfer hydrogenation reaction. A simple nickel/BenzP* catalyst displayed high activity in both steps of regioselective hydrocarboxylation of alkynes and subsequent asymmetric transfer hydrogenation. The reaction was successfully applied in enantioselective preparation of three nonsteroidal anti-inflammatory profens (>90 % ees) and the chiral fragment of AZD2716. 相似文献
74.
A new expression for contact deformation is given, and the normal contact stiffness between single asperities is derived according to Hooke’s law. A contact model between two ellipsoidal asperities is simulated by the FE method, the result compared with the theoretical solution. It is found that the curves of the normal contact stiffness versus the included angle in the principal curvature direction show similar trends and evolve as a cosine feature. The effects of the parameters on normal contact stiffness are found to show that normal contact stiffness increases and reaches the upper limit gradually with an increase in these parameters. 相似文献
75.
76.
Cover Picture: One‐Step Synthesis of Silver Nanoparticle‐Decorated Hydroxyapatite Nanowires for the Construction of Highly Flexible Free‐Standing Paper with High Antibacterial Activity (Chem. Eur. J. 32/2016) 下载免费PDF全文
77.
78.
Yue Zhang Jing Liu Longchuan Li Minyi Du Wenxue Fang Dongxin Wang Xuexiang Jiang Xiaoping Hu Jue Zhang Xiaoying Wang Jing Fang 《Magnetic resonance imaging》2014
Understanding the effect of postherpetic neuralgia (PHN) pain on brain activity is important for clinical strategies. This is the first study, to our knowledge, to relate PHN pain to small-world properties of brain functional networks. Functional magnetic resonance imaging (fMRI) was used to construct functional brain networks of the subjects during the resting state. Sixteen patients with PHN pain and 16 (8 males, 8 females for both groups) age-matched controls were studied. The PHN patients exhibited decreased local efficiency along with non-significant changes of global efficiency in comparison with the healthy controls. Moreover, regional nodal efficiency was found to be significantly affected by PHN pain in the areas related to sense (postcentral gyrus, inferior parietal gyrus and thalamus), memory/affective processes (parahippocampal gyrus) and emotional activities (putamen). Significant correlation (p < 0.05) was also found between the nodal efficiency of putamen and pain intensity in PHN patients. Our results suggest that PHN modulates the local efficiency, and the small-world properties of brain networks may have potentials to objectively evaluate pain information in clinic. 相似文献
79.
CUI Yuan-min FENG Jie-qing 《高校应用数学学报(英文版)》2014,(4):455-467
We implemented accurate FFD in terms of triangular Bezier surfaces as matrix multiplications in CUDA and rendered them via OpenGL. Experimental results show that the proposed algorithm is more efficient than the previous GPU acceleration algorithm and tessel- lation shader algorithms. 相似文献
80.
Low‐temperature headspace‐trap gas chromatography with mass spectrometry for the determination of trace volatile compounds from the fruit of Lycium barbarum L. 下载免费PDF全文
The total saccharides content of Lycium barbarum L. is very high, and a high temperature would result in saccharide decomposition and the emergence of a large amount of water. Moreover, the volatile compounds from the fruit of L. barbarum L. are rather low in concentration. Hence, it is difficult for a conventional headspace method to study the volatile compounds from the fruit of L. barbarum L. Since headspace‐trap gas chromatography with mass spectrometry is an excellent method for trace analysis, a headspace‐trap gas chromatography with mass spectrometry method based on low‐temperature (30°C) enrichment and multiple headspace extraction was developed to explore the volatile compounds from the fruit of L. barbarum L. The headspace of the sample was extracted in 17 cycles at 30°C. Each time, the compounds extracted were concentrated in the trap (Tenax TA and Tenax GR, 1:1). Finally, all the volatile compounds were delivered into the gas chromatograph after thermal desorption. With the method described above, a total of 57 compounds were identified. The identification was completed by mass spectral search, retention index, and accurate mass measurement. 相似文献