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991.
Fractionation of the methanolic extract of the stromata of Hypoxylon rutilum (Xylariaceae, Ascomycetes) resulted in the isolation of two novel dimeric azaphilones named rutilins A and B, together with the known compounds, entonaemin A, and rubiginosins A and B. Their structures were elucidated by 2D NMR, HR-MS, IR and UV spectroscopy. Rutilins A and B are presumably synthesized via specific biogenic aldol condensations of mitorubrinol acetate moieties with rubiginosins A and B, respectively. The resulting dimeric azaphilone scaffold of the rutilins is unprecedented in nature. 相似文献
992.
Hongxing Zheng Tao Dang Lihui Jiang 《International Journal of Infrared and Millimeter Waves》2004,25(5):865-874
To investigate the infrared photonic crystal devices numerically, the traditional finite-difference time-domain (FDTD) method has been modified by combining with a new alternating direction implicit (ADI) algorithm. An improvement of two-five in speed over previous FDTD methods can be obtained by calculating the envelope rather than the fast-varying field, and the numerical errors are minimized. Consider the isolated localized coupled-cavity modes, the phenomenon of eigenmode splitting has been observed when the coupled-cavity structures in two dimension triangular dielectric photonic crystals are simulated. The results are in good agreement with experiments. 相似文献
993.
We show that every supersingular K3 surface in characteristic 5 with Artin invariant ≤ 3 is unirational. 相似文献
994.
Kim Dang Phung 《Journal of Mathematical Analysis and Applications》2004,293(2):389-404
In this paper, the null asymptotic stabilization of the 2D Euler equations of incompressible fluids in a simply connected bounded domain is investigated by utilizing the Lorentz force given by the Maxwell equations with Ohm's law. 相似文献
995.
996.
Genetic diversity and haplotype structure of 24 Y‐chromosomal STR in Chinese Hui ethnic group and its genetic relationships with other populations
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Bo‐Feng Zhu Yu‐Dang Zhang Wen‐Juan Liu Hao‐Tian Meng Guo‐Lian Yuan Zhe Lv Nan Dong Qiong Li Chun‐hua Yang Yu‐Hong Zhang Yin‐Ling Hou Li Qian Shuan‐Liang Fan Peng Xu 《Electrophoresis》2014,35(14):1993-2000
In the present study, 24 Y‐chromosomal short tandem repeat (Y‐STR) loci were analyzed in 115 unrelated Hui male individuals from Haiyuan county or Tongxin county, Ningxia Hui Autonomous Region, China, to evaluate the forensic application of the 24 STR loci and to analyze interpopulation differentiations by making comparisons between the Hui group data and previously published data of other 13 populations. A total of 115 different haplotypes were observed on these 24 Y‐STR loci. The gene diversities ranged from 0.4049 (DYS437) to 0.9729 (DYS385a, b). The overall haplotype diversity was 1 at AGCU 24 Y‐STR loci level, while the values were reduced to 0.999237, 0.996949, and 0.996644 at the Y‐filer 17 loci, 11 Y‐STR loci of extended haplotype and 9 Y‐STR loci of minimal haplotype levels, respectively; whereas, haplotype diversity for additional 7 loci (not included in Y‐filer 17 loci) was 0.995271. The pairwise FST, multidimensional scaling plot and neighbor‐joining tree indicated the Hui group had the closest genetic relationship with Sala in the paternal lineage in the present study. In summary, the results in our study indicated the 24 Y‐STRs had a high level of polymorphism in Hui group and hence could be a powerful tool for forensic application and population genetic study. 相似文献
997.
Structural polymorphism analysis of Chinese Mongolian ethnic group revealed by a new STR panel: Genetic relationship to other groups
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Chun‐Mei Shen Hua Wu Guo‐lian Yuan Li‐Jun Zhao Jiang‐Wei Yan Hao‐Tian Meng Yu‐Dang Zhang Wen‐Juan Liu Hong‐Dan Wang Richard E. White Xing Wei 《Electrophoresis》2014,35(14):2008-2013
Mongolian is the eighth largest ethnic minority on Chinese population data according to the 2010 census. In the present study, we presented the first report about the allelic frequencies and forensic statistical parameters at the 21 new STRs and analyzed linkage disequilibrium of pairwise loci in the Mongolian ethnic minority, China. Hardy–Weinberg equilibrium tests demonstrated no significant deviations except for the D1S1627 locus. The cumulative power of discrimination and power of exclusion of all the loci are 0.9999999999999999992576 and 0.9999997528, respectively. The results of analysis of molecular variance showed that significant differences between the Mongolian and the other eight populations were found at 1‐9 STR loci. In population genetics, the results of principal component analysis, structure analysis, and phylogenetic reconstruction analysis indicated shorter genetic distance between the Mongolian group and the Ningxia Han. All the results suggest that the 21 new STR loci will contribute to Chinese population genetics and forensic caseworks in the Mongolian group. 相似文献
998.
Tran Duc Thiep Truong Thi An Phan Viet Cuong Nguyen The Vinh Bui Minh Hue A. G. Belov O. D. Maslov 《Journal of Radioanalytical and Nuclear Chemistry》2014,299(1):477-484
We measured for the first time the isomeric ratios in 107Ag(γ, n)106m,gAg reaction by using the activation method and γ-ray spectroscopic method for the whole giant dipole resonance region. The high-purity natural Ag foils in disc shape were irradiated with bremsstrahlungs generated from an electron accelerator Microtron. The induced gamma spectra in the irradiated foils were measured by the high resolution γ-ray spectroscopic system which consists of a high-purity germanium detector and a multichannel analyzer. In order to improve the accuracy of the experimental results, necessary corrections were made in the γ-ray activity measurements and data analysis. The results were analyzed, discussed and compared with those of other authors. For the above mentioned reaction, the isomeric ratios in the energy range from 14 to 24 MeV bremsstrahlungs in this work (except the values at 14, 18 and 20) are new measurements. 相似文献
999.
Sung-Chul Yang Guinyun Kim M. Zaman Kwangsoo Kim Tae-Yung Song Young-Ouk Lee Sung Gyun Shin Young-Uk Key Moo-Hyun Cho Duc Khue Pham Van Do Nguyen Haladhara Naik Tae-Ik Ro 《Journal of Radioanalytical and Nuclear Chemistry》2014,302(1):467-476
The independent isomeric yield ratios of 148Pm from the natSm(γ, x) reaction at the end-point bremsstrahlung energy of 45–64 MeV have been determined using an off-line γ-ray spectrometric technique at the 100 MeV electron linac of Pohang accelerator laboratory, Pohang, Korea. We also have determined the isomeric yield ratios of 148Pm from the natNd(p,xn) reactions in the proton energy of 5.08–44.72 MeV by a stacked-foil activation and an off-line γ-ray spectrometric techniques at the MC-50 cyclotron of the Korean Institute of Radiological and Medical Sciences, Korea. The determined isomeric yield ratios of 148Pm were compared with literature data and theoretical values estimated by the TALYS 1.4. The present data along with the similar data from literature at other energies shows that the isomeric yield ratio of 148Pm increases with the excitation energy both in the natSm(γ, x) and the natNd(p, xn) reactions. The isomeric yield ratios of 148Pm from the natNd(p, xn) reactions are always higher than those from the natSm(γ, x) reactions at the same excitation energy, which indicate the role of input angular momentum besides excitation energy. 相似文献
1000.
Dr. Fei-Yue Gao Dr. Shao-Jin Hu Dr. Xiao-Long Zhang Dr. Ya-Rong Zheng Hui-Juan Wang Zhuang-Zhuang Niu Peng-Peng Yang Rui-Cheng Bao Dr. Tao Ma Zheng Dang Prof. Yong Guan Prof. Xu-Sheng Zheng Prof. Xiao Zheng Prof. Jun-Fa Zhu Prof. Min-Rui Gao Prof. Shu-Hong Yu 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2020,132(22):8784-8790
A considerable challenge in the conversion of carbon dioxide into useful fuels comes from the activation of CO2 to CO2.− or other intermediates, which often requires precious-metal catalysts, high overpotentials, and/or electrolyte additives (e.g., ionic liquids). We report a microwave heating strategy for synthesizing a transition-metal chalcogenide nanostructure that efficiently catalyzes CO2 electroreduction to carbon monoxide (CO). We found that the cadmium sulfide (CdS) nanoneedle arrays exhibit an unprecedented current density of 212 mA cm−2 with 95.5±4.0 % CO Faraday efficiency at −1.2 V versus a reversible hydrogen electrode (RHE; without iR correction). Experimental and computational studies show that the high-curvature CdS nanostructured catalyst has a pronounced proximity effect which gives rise to large electric field enhancement, which can concentrate alkali-metal cations resulting in the enhanced CO2 electroreduction efficiency. 相似文献