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Fengyun Li Junping Yu Zhiping Zhang Zongqiang Cui Dianbing Wang Hongping Wei Xian-En Zhang 《Analytica chimica acta》2012
Bioluminescence resonance energy transfer (BRET) has gained favors in recent years as a detection technology for protease activity due to its extreme reliability, high sensitivity and low intrinsic backgrounds. Because of the sensitivity of the donors, substrates and the acceptors, it is expected that BRET systems are sensitive to buffer environments. However, no systematic study has been reported on how buffer components would affect the BRET ratio, and thus affect the determination of protease activity based on BRET. We present here that several environmental factors, including buffer agents, pH and divalent metal ions, influenced BRET ratio significantly, when humanized Gaussia luciferase (hGluc) was utilized as the donor and enhanced yellow fluorescence protein (EYFP) as the acceptor. Based on these findings, an enhancing solution was optimized to improve the performance of the BRET sensor for analysis of enterokinase activity in vitro, resulting in 10-fold and 7-fold improvement of the sensitivity and the detection limit, respectively. We anticipate the system will be applicable for improving performance of other in vitro BRET protease sensors, especially when the optimal conditions for protease activity would severely affect the BRET signal. 相似文献
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Prof. Hongping Wu Dr. Bingbing Zhang Hongwei Yu Zhanggui Hu Jiyang Wang Yicheng Wu Prof. P. Shiv Halasyamani 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2020,132(23):9007-9011
Discovering new deep-ultraviolet (DUV) nonlinear optical (NLO) materials is currently a great challenge. The reported DUV NLO materials are almost exclusively borates or phosphates. Silicates—the largest constituent of the earth's crust—are excluded owing to their weak second harmonic generation (SHG) response. We report a silicate, Li2BaSiO4, with edge-sharing LiO4–SiO4 tetrahedra that achieves the balance between a short UV absorption edge, below 190 nm, and a large SHG response, 2.8×KDP. The SHG intensity is the largest for silicates without second-order Jahn–Teller cations, and exceeds that of non-isomorphic Li2SrSiO4 by more than an order of magnitude. As such Li2BaSiO4 may be seen as a promising DUV-UV NLO material. This research indicates that edge-sharing tetrahedra is a new design parameter for discovering new DUV NLO materials. 相似文献
186.
<正>We present high resolution photoelectron energy spectra from multiphoton ionization(MPI) of Ar subject to laser pulses with wavelength of 400 nm,pulse duration of 35 fs,and maximum intensity of 5×10~(13) W/cm~2.Ionizations into Ar~+ ~2P_(3/2) and ~2P_(1/2) channels are observed and distinct resonance structures are found in both ionization channels.The intensity dependence of the resonance structures is explained in terms of the mechanism of Freeman resonance,i.e.,transient resonances of alternating current (AC) Stark-shifted Rydberg states at specific intensities within the laser pulse. 相似文献
187.
We have systematically investigated the electronic and magnetic properties of hypothesized A‐site‐ordered perovskite YMn3Sc4O12 using first‐principle calculation based on the density functional theory. Our calculated results predict that YMn3Sc4O12 is both thermodynamically and mechanically stable and its ground state is antiferromagnetic insulator. The Mn3+ is in the high‐spin state. More importantly, by comparison to YMn3Al4O12, we point out that the empty Sc 3d orbital provides the Mn? O? Sc? O? Mn superexchange interaction, which is similar to its isostructural perovskite CaCu3Ti4O12, and enhances the antiferromagnetic interaction between Mn ions. From these calculations, we can clearly see that the empty 3d orbital plays an important role to realize superexchange interaction. © 2011 Wiley Periodicals, Inc. J Comput Chem, 2011 相似文献
188.
Shuai Chen Hongping Li Hua Tang Yi Zhang Jin Yang Xiao Rui Ji Lin Chen Kun Zhang Changsheng Li 《Crystal Research and Technology》2014,49(2-3):152-158
Doping of NbSe2 with heteroatoms is an effective way to tailor its properties. Here, solid phase synthesis process has been utilized for growing uniform and excellent crystalline nano‐NbSe2 by sulfur dopant during the growing process. The sulfur‐doped mechanism of nano‐NbS2xSe2(1‐x)(x = 0.03∼0.2) has been investigated: the sulfur atoms not only replace the Se position but also intercalate in layer gap by one‐step reaction. In the structure of NbSe2, the sulfur atoms replace the positions of Se atoms and then are located in the empty octahedral positions of van der waals gap between the NbSe2 layers with the increase of sulfur content. The lubrication properties of the as‐prepared NbSe2 and sulfur‐doped NbSe2 powders as additives in HVI1500 base oil were discussed. The lubrication properties of base oil was improved by both NbSe2 and sulfur‐doped NbSe2. Furthermore, the lubrication properties of sulfur‐doped (0.1at%) NbSe2 are better than those of pure NbSe2 in HVI1500 base oil, which could be attributed to their thin laminated structure and the sulfur dopant. 相似文献
189.
The waste disposal charging fee (WDCF) has long been adopted for stimulating major project stakeholders’ (particularly project clients and contractors) incentives to minimize solid waste and increase the recovery of wasted materials in the construction industry. However, the present WDCFs applied in many regions of China are mostly determined based on a rule of thumb. Consequently the effectiveness of implementing these WDCFs is very limited. This study aims at addressing this research gap through developing a system dynamics based model to determine an appropriate WDCF in the construction sector. The data used to test and validate the model was collected from Shenzhen of south China. By using the model established, two types of simulations were carried out. One is the base run simulation to investigate the status quo of waste generation in Shenzhen; the other is policy analysis simulation, with which an appropriate WDCF could be determined to reduce waste generation and landfilling, maximize waste recycling, and minimize the waste dumped inappropriately. The model developed can function as a tool to effectively determine an appropriate WDCF in Shenzhen. Further, it can also be used by other regions intending to stimulate construction waste minimization and recycling through implementing an optimal WDCF. 相似文献
190.
以鞅变换为工具,刻画了LΦ可料控制鞅的Hardy-Orlicz空间之间的相互关系,设Φ1和Φ2是两个Young函数,并在某种意义上Φ2强于Φ1(具体定义见正文),以构造性的方法证明了Hardy-Orlicz空间(D)Φ1中的鞅恰好是Hardy-Orlicz空间(D)Φ2中的鞅的鞅变换.所得的结果推广了已有文献中的相关结论. 相似文献