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31.
Mass spectrometry-based qualitative and quantitative (bio)molecular analysis is a corner stone in the state-of-the-art pipelines in systems biology and environmental sciences. High-resolution and efficient tandem mass spectrometry methods and techniques are the essential analytical capabilities for the in-depth analysis of extremely complex mixtures of (bio)molecules of a very broad dynamic range of concentrations. Here, we briefly review the advantages and limitations of the current mass spectrometry with a focus on resolution, or resolving power, and methods of (bio)molecular fragmentation in the gas phase. We conclude with an outlook that considers possible avenues for further mass spectrometry-based method and technique development, indispensable for advancing the challenging real-life mass spectrometry applications in the XXI century. 相似文献
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软件测试用例生成综合策略研究 总被引:3,自引:3,他引:3
在软件测试中,测试用例生成是其关键环节,也对软件测试的自动化有着重要影响。为了提高测试用例生成的效率,提高其自动化的程度,从不同角度对软件测试用例选择策略进行介绍,并且着重介绍了采用遗传算法作为核心搜索算法来自动生成用例的方法,对其中的关键问题进行了探讨,最后,结合实际测试过程总结了测试用例生成的综合策略。 相似文献
34.
Effect of Irpex lacteus,Pleurotus ostreatus and Pleurotus cystidiosus pretreatment of corn stover on its improvement of the in vitro rumen fermentation
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35.
Yiting Tao Sasa Yan Ying Du Panting Wang Danping Chen 《Ceramics International》2021,47(13):18030-18036
In this study, Eu2+/Al3+-, Eu2+/Tb3+-, and Eu2+/Tb3+/Al3+-doped high silica glasses were prepared, and the effect of Al3+ on the spectroscopic properties of Eu2+ and Tb3+ and the energy transfer of Eu2+→Tb3+ was investigated. The results revealed that the addition of Al3+ increased the luminescent intensity of the Eu2+-doped glass by approximately 400 times. An obvious Eu2+→Tb3+ energy transfer occurred in the Eu2+/Tb3+-doped high silica glass, whose transfer efficiency can reached 66.9%. However, the efficiency continuously decreased as the Al3+ concentration increased, and eventually, it dropped to 7.2%. These phenomena can be explained by the following: Al3+ not only disperses Eu2+ but also changes the field strength and symmetry of its neighboring environment, thus increasing its emission intensity. Moreover, Al3+ destroys the strong dipole–dipole interactions between Eu2+ and Tb3+ in high silica glass due to its dispersive ability, which inhibits the energy transfer of Eu2+→Tb3+. This indicates that a small amount of Al3+ can significantly modify the neighboring environment of Eu2+ and change its light-emitting characteristics, potentially yielding efficient blue and green phosphors excited by near-ultraviolet light for use in white light-emitting diodes. 相似文献
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37.
Carbamide peroxide bleaching of teeth with dentinogenesis imperfecta discoloration: report of a case
Carbamide peroxide dental bleaching has gained much popularity in the past 5 years. Because tooth discoloration caused by dentinogenesis imperfecta involves deep, dark, dentinal stain, practitioners might believe that affected teeth would be resistant to color improvement by bleaching. This article reports the successful use of carbamide peroxide at-home bleaching in a teenager with dentinogenesis imperfecta. Six-month treatment results are shown. 相似文献
38.
2D Hybrid Perovskite Ferroelectric Enables Highly Sensitive X‐Ray Detection with Low Driving Voltage
Chengmin Ji Sasa Wang Yaxing Wang Huaixi Chen Lina Li Zhihua Sun Yan Sui Shuao Wang Junhua Luo 《Advanced functional materials》2020,30(5)
X‐ray detectors with high sensitivity are of great significance in both civil and military fields. Over the past decades, great efforts have been made to improve the sensitivity in conventional inorganic materials, but mainly at the cost of increasing the energy consumption with a quite high operating voltage. Developing photosensitive ferroelectrics directly as detector materials may be a conceptually new strategy in view of the strong ferroelectric spontaneous polarization (Ps) that assists photoinduced carriers separation and transport. A high‐performance X‐ray detector in 2D hybrid halide perovskite ferroelectric (C4H9NH3)2(C2H5NH3)2Pb3Br10 ( BA2EA2Pb3Br10 ) (Ps = 5 µC cm?2) is fabricated and exhibits an ultrahigh X‐ray sensitivity up to 6.8 × 103 µC Gyair?1 cm?2 even at a relatively low operating voltage, which is over 300‐fold larger than that of state‐of‐the‐art α‐Se X‐ray detectors. Such a brilliant figure‐of‐merit is largely attributed to the superior mobility–lifetime products associated with the strong ferroelectric polarization of BA2EA2Pb3Br10 . As pioneering work, these findings inform the exploration of hybrid halide perovskite ferroelectrics toward high‐performance photoelectronic devices. 相似文献
39.
Chengmin Ji Sasa Wang Lina Li Zhihua Sun Maochun Hong Junhua Luo 《Advanced functional materials》2019,29(6)
Luminescent ferroelectrics have attracted considerable attention in terms of integrated photoelectronic devices, most of which are focused on the multicomponent systems of rare‐earth doping ferroelectric ceramics. However, bulk ferroelectricity with coexistence of strong white‐light emission, especially in the single‐component system, remains quite rare. Here, a new organic–inorganic hybrid ferroelectric of (C4H9NH3)2PbCl4 ( 1 ) is reported, adopting a 2D layered perovskite architecture, which exhibits an unprecedented coexistence of notable ferroelectricity and intrinsic white‐light emission. Decent above‐room‐temperature spontaneous polarization of ≈2.1 µC cm?2 is confirmed for 1 . Particularly, it also exhibits brilliant broadband white‐light emission with a high color‐rendering‐index up to 86 under UV excitation. Structural analyses indicate that ferroelectricity of 1 originates from molecular reorientation of dynamic organic cations, as well as significant structural distortion of PbCl6 octahedra that also contribute to its white‐light emission. This work paves an avenue to design new hybrid ferroelectrics for multifunctional application in the photoelectronic field. 相似文献
40.
In situ SAXS is used to investigate the shear-induced alignment of a supramolecular system consisting of a polyisoprene-b-poly(2-vinylpyridine) diblock copolymer and octyl gallate (OG), where OG is hydrogen-bonded to the vinylpyridine block of the PI-b-P2VP copolymer. Due to microphase separation, the PI-b-P2VP(OG) system self-assembles forming a domain structure of hexagonally ordered P2VP(OG) cylinders embedded in the PI matrix. The results of the alignment showed that the orientation mobility of the cylinders, lying within the (10) planes parallel to the shear plane, is strongly dependent on the size of the cylindrical domains. Subjected to large amplitude oscillatory shear for 15 min a freshly loaded sample with a small grain size structure exhibited much better alignment compared to that of a pre-aligned/squeezed sample with a considerably larger grain size where the orientation had been first partly destroyed by squeezing. 相似文献