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991.
Dr. Mengmeng Jiao Wenzhen Lv Wei Lü Qi Zhao Baiqi Shao Prof. Hongpeng You 《Chemphyschem》2015,16(4):817-824
A series of Eu2+‐, Ce3+‐, and Tb3+‐doped Ca2Ga2SiO7 phosphors is synthesized by using a high‐temperature solid‐state reaction. The powder X‐ray diffraction and structure refinement data indicate that our prepared phosphors are single phased and the phosphor crystalizes in a tetrahedral system with the ${P\bar 42m}$ (113) space group. The Eu2+‐ and Ce3+‐doped phosphors both have broad excitation bands, which match well with the UV light‐emitting diodes chips. Under irradiation of λ=350 nm, Ca2Ga2SiO7:Eu2+ and Ca2Ga2SiO7:Ce3+, Li+ have green and blue emissions, respectively. Luminescence of Ca2Ga2SiO7:Tb3+, Li+ phosphor varies with the different Tb3+ contents. The thermal stability and energy‐migration mechanism of Ca2Ga2SiO7:Eu2+ are also studied. The investigation results indicate that the prepared Ca2Ga2SiO7:Eu2+ and Ca2Ga2SiO7:Ce3+, Li+ samples show potential as green and blue phosphors, respectively, for UV‐excited white‐light‐emitting diodes. 相似文献
992.
An ultra high performance liquid chromatography with tandem mass spectrometry method for plasma and cerebrospinal fluid pharmacokinetics of rhein in patients with traumatic brain injury after administration of rhubarb decoction
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Yang Wang Rong Fan Jiekun Luo Tao Tang Zhihua Xing Zian Xia Weijun Peng Wenzhu Wang Huiying Lv Wei Huang Yizeng Liang Lunzhao Yi Hongmei Lu Xi Huang 《Journal of separation science》2015,38(7):1100-1108
Damage of blood–brain barrier is a common result of traumatic brain injury. This damage can open the blood–brain barrier and allow drug passage. An ultraperformance liquid chromatography with tandem mass spectrometry method was established to determine the concentration of rhein in the biofluids (plasma and cerebrospinal fluid) of patients with a compromised blood–brain barrier following traumatic brain injury after rhubarb administration. Furthermore, the pharmacokinetic profiles were analyzed. A triple‐quadruple tandem mass spectrometer with electrospray ionization was used for rhein detection. The mass transition followed was m/z 283.06→239.0. The calibration curve was linear in the concentration range of 10–8000 ng/mL for the biofluids. The intra‐ and interday precisions were less than 10%. The relative standard deviation of recovery was less than 15% in biological matrices. The pharmacokinetic data showed that rhein was rapidly transported into biofluids, and exhibited a peak concentration 1 h after rhubarb administration. The elimination rate of rhein was slow. The AUCcerebrospinal fluid/AUCplasma (AUC is area under curve) of rhein was approximately 17%, indicating that portions of rhein could pass the impaired blood–brain barrier. The method was successfully applied to quantify rhein in the biofluids of all patients. The data presented can help to guide clinical applications of rhubarb for treating traumatic brain injury. 相似文献
993.
994.
Ranran Zhang Yu Tan Hui Jian Shengqiu Qu Yuqing Liu Jing Zhu Li Wang Meili Lv Miao Liao Lin Zhang Fan Yang Weibo Liang 《Electrophoresis》2020,41(13-14):1189-1197
Microhaplotypes are a new promising type of forensic genetic marker. Without the interference of stutter and high mutation rates as for STRs, and with short amplification lengths and a higher degree of polymorphism than single SNP, microhaplotypes composed of two SNPs, SNP–SNP, have a strong application potential. Currently, the most common method to detect microhaplotypes is massive parallel sequencing. However, the cost and extensive use of instruments limit its wide application in forensic laboratories. In this study, we screened 23 new SNP–SNP loci and established a new detection method by combining a multiplex amplification refractory mutation system-based PCR (ARMS-PCR) and SNaPshot technology based on CE. First, we introduced an additional deliberate mismatch at the antepenultimate base from the 3′ end of primers when designing ARMS-PCR for SNP 1 (the first SNP of the SNP–SNP). Then, single base extension primers for SNaPshot assay were designed next to the position of SNP 2 (the second SNP). Finally, 15 loci were successfully built into four panels and these loci showed a relatively high level of polymorphism in the Southwest Chinese Han population. All the loci had an average probability of informative genotypes (I value) of 0.319 and a combined discrimination power of 0.999999999. Therefore, this new detection system will provide a valuable supplement to current methods. 相似文献
995.
Dr. Yinhua Lv Ruihan Yuan Dr. Bing Cai Behzad Bahrami Ashraful Haider Chowdhury Dr. Chi Yang Dr. Yihui Wu Prof. Qiquan Qiao Prof. Shengzhong Liu Prof. Wen-Hua Zhang 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2020,132(29):12067-12074
One-dimensional (1D) nanostructured oxides are proposed as excellent electron transport materials (ETMs) for perovskite solar cells (PSCs); however, experimental evidence is lacking. A facile hydrothermal approach was employed to grow highly oriented anatase TiO2 nanopyramid arrays and demonstrate their application in PSCs. The oriented TiO2 nanopyramid arrays afford sufficient contact area for electron extraction and increase light transmission. Moreover, the nanopyramid array/perovskite system exhibits an oriented electric field that can increase charge separation and accelerate charge transport, thereby suppressing charge recombination. The anatase TiO2 nanopyramid array-based PSCs deliver a champion power conversion efficiency of approximately 22.5 %, which is the highest power conversion efficiency reported to date for PSCs consisting of 1D ETMs. This work demonstrates that the rational design of 1D ETMs can achieve PSCs that perform as well as typical mesoscopic and planar PSCs. 相似文献
996.
Jie Liang Qiyuan Chen Xiangbiao Liao Pengcheng Yao Dr. Bin Zhu Guangxin Lv Xinyu Wang Xi Chen Prof. Jia Zhu 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2020,132(16):6623-6628
Lithium dendrite growth during repeated charge and discharge cycles of lithium-metal anodes often leads to short-circuiting by puncturing the porous separator. Here, a morphological design, the nano-shield, for separators to resist dendrites is presented. Through both mechanical analysis and experiment, it is revealed that the separator protected by the nano-shield can effectively inhibit the penetration of lithium dendrites owing to the reduced stress intensity generated and therefore mitigate the short circuit of Li metal batteries. More than 110 h of lithium plating life is achieved in cell tests, which is among the longest cycle life of lithium metal anode and five times longer than that of blank separators. This new aspect of morphological and mechanical design not only provides an alternative pathway for extending lifetime of lithium metal anodes, but also sheds light on the role of separator engineering for various electrochemical energy storage devices. 相似文献
997.
In this paper, a car-following model considering anticipation-driving behavior is considered to describe the traffic jam. The nature of the model is investigated using linear and nonlinear analysis method. A thermodynamic theory is formulated for describing the phase transitions and critical phenomena, and the time-dependent Ginzburg–Landau equation is derived to describe traffic flow near the critical point. 相似文献
998.
The complete diagonalization (of energy matrix) method (CDM) and the perturbation theory method (PTM) are applied to calculate the spin-Hamiltonian (SH) parameters (electron paramagnetic resonance g factors g //, g ⊥ and zero-field splitting D) of the trigonal Mo 3+ centers in Y 3Al 5O 12 and Lu 3Al 5O 12 crystals. Both methods are based on the cluster approach in which the covalence effect due to the admixture between the d orbitals of central d n ion and p orbitals of ligands is considered. The g factors calculated by both methods are close to each other and agree with the experimental values. However, the calculated zero-field splittings D from PTM for both crystals are about 84% those from CDM. The reasons that the CDM is preferable to the PTM in the calculations of SH parameters are discussed. The angular distortions of Mo 3+ centers in both garnet crystals are predicted. 相似文献
999.
ABSTRACTThe specific activities of 226Ra, 232Th and 40K of 26 samples of granite produced in Xinjiang of China were measured by a high-purity germanium detector, and their radiological hazards of radium equivalent, external hazard index, internal hazard index, absorbed dose rate, annual effective dose rate, gamma index and alpha index were evaluated. The results indicate that the overall average specific activities of 226Ra, 232Th and 40K obtained in the investigated samples are below the world’s average granite values. The average radium equivalent is within the recommended limit of 370?Bq?kg?1. The results obtained further show that the mean values of external hazard index, internal hazard index, absorbed dose rate, annual effective dose rate, gamma index and alpha index are 0.65, 0.77, 111.7?nGy?h?1, 0.55 mSv?y?1, 0.89 and 0.23, respectively. These mean values established that radiological hazards are also found to be below the international recommended values. The results are compared with granite samples from other countries or China-Taiwan province. It can be noticed that the specific activity values of granite samples produced in China are lower or similar to that of other countries or China-Taiwan province, however there are higher specific activity values for 226Ra and 232Th in individual samples, which need to provide proper radiation monitoring before use considering the long term health effect. 相似文献
1000.