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101.
We study two aspects of higher dimensional operators in standard model effective field theory.We first introduce a perturbative power counting rule for the entries in the anomalous dimension matrix of operators with equal mass dimension.The power counting is determined by the number of loops and the difference of the indices of the two operators involved,which in turn is defined by assuming that all terms in the standard model Lagrangian have an equal perturbative power.Then we show that the operators with the lowest index are unique at each mass dimension d,i.e.,(H~?H)~(d/2)for even d≥4,and(L~TεH)C(L~TεH)~T(H~?H)~((d-5)/2)for odd d≥5.Here H,L are the Higgs and lepton doublet,andε,C the antisymmetric matrix of rank two and the charge conjugation matrix,respectively.The renormalization group running of these operators can be studied separately from other operators of equal mass dimension at the leading order in power counting.We compute their anomalous dimensions at one loop for general d and find that they are enhanced quadratically in d due to combinatorics.We also make connections with classification of operators in terms of their holomorphic and anti-holomorphic weights. 相似文献
102.
103.
Shih-Ming Hsu Hsi-Wen Yang Yung-Hui Huang Jeng-Hung Lee Chun-Yen Yu Yi-Jen Liao Shick-Kai Hung Moon-Sing Lee 《Radiation measurements》2010,45(3-6):553-555
Thermoluminescent dosimeters are widely applied in the measurement of radiation dose. Since the luminescent centers are not lost during the reading process, radiophotoluminescent glass dosimeters (RPLGDs) can be repeatedly readout. The aims of this study were to make RPLGD and to analyze its physical and chemical properties. This study used chemical compounds such as Na3PO4, AlPO4, AgCl, AgNO3, B2O3, H3PO4 and P2O5 as the main ingredients. Depending on the self-fabricated glass compounds, the melting temperatures were between 1100 and 1500 °C. When the 0.1 mol% of silver was added, the radiation detection of self-fabricated RPLGD reached to the highest sensitivity. However, when silver concentration was larger than 0.1 mol%, the radiation detection sensitivity plummets rapidly. Excess amounts of silver and aluminum decreased the penetrate capability of ultraviolet spectrum. Based on our study, we found that chemical compound concentrations and melting process, which all affect radiation sensitivity and stability of self-fabricated RPLGD. 相似文献
104.
105.
Xiaoyan Deng Guihong Liao Qingwu Long Yujiao Gao Hao Peng Hongwu He 《Phosphorus, sulfur, and silicon and the related elements》2013,188(6):663-671
Abstract A series of [(substituted phenoxyacetoxy)(substituted phenyl)methyl](methyl)phos- phinates containing fluorine were designed and synthesized. All the synthesized compounds were identified by elemental analysis, IR, 1H NMR, mass spectrometry. O-methyl [(2-fluorophenoxyacetoxy)(2,4-dichlorophenyl)methyl](methyl)phosphinate was further analyzed by X-ray single-crystal diffraction. Their herbicidal activity against a set of weed species was examined. Some of the compounds showed potential herbicidal activity, which provided some indications for further studies on structure modification. Supplemental materials are available for this article. Go to the publisher's online edition of Phosphorus, Sulfur, and Silicon and the Related Elements to view the free supplemental file. 相似文献
106.
H. Xia X. Jiang L. Lin C. Jiang G. Liao 《Russian Journal of Coordination Chemistry》2013,39(12):896-901
Reaction of a macrocyclic copper(II) complex [Cu(L)](ClO4)2 · 3H2O (I) (L = 1,3,10,12,16,19-hexaazatetracyclotetracosane) with a hexapod carboxylate ligand H6TTHA (H6TTHA = 1,3,5-triazine-2,4,6-triamine hexaacetic acid) and a tripod carboxylate ligand H3TATB (H3TATB = 4,4′,4″-S-triazine-2,4,6-triyl-tribenzoic acid) yielded two mononuclear copper(II) complexes [Cu(L)][H4TTHA] · 4H2O (II) and [Cu(L)][HTATB] · 4H2O (III). The complexes I–III have been structurally characterized. The crystal structures of complexes II and III show the copper(II) ion has a distorted pentacoordinate square-pyramidal geometry with two secondary and two tertiary amines from the macrocyclic complex [Cu(L)]2+ and one oxygen atom from the carboxylate ligand group at the axial position. The UV-Vis spectra are utilized to discuss the hydrolysis of the complex II. 相似文献
107.
Bei‐Bei Zhang Qian Jiang Zhi‐Xin Liao Chao Liu Shi‐Jun Liu 《Helvetica chimica acta》2013,96(7):1281-1289
Phytochemical investigation of the EtOH extract of Euphorbia sieboldiana led to the isolation of four new oleanane‐type triterpenoids, (1β,2α,3β,19β)‐1,2,3,19‐tetrahydroxyolean‐12‐en‐28‐oic acid, (1β,3β,19β)‐1,3,19‐trihydroxyolean‐12‐en‐28‐oic acid, (1β,2α,3β,16β,19β)‐1,2,3,16,19‐pentahydroxyolean‐12‐en‐28‐oic acid, and (1β,2α,3β,19β,23)‐1,2,3,19,23‐pentahydroxyolean‐12‐en‐28‐oic acid, along with 16 known compounds. Their structures were established by extensive 1D‐ and 2D‐NMR, as well as other spectral analyses. Biological evaluation of the four new triterpenoids revealed potent cytotoxic activities against HeLa and Hep‐G2 cells. 相似文献
108.
Novel symmetrical D–A–D type of BODIPY derivatives (DTPA–BDP) were synthesized successfully. The introduction of chromophoric units makes the molecule absorption wavelengths spanning the ranges of 300–800 nm and shifts the emission to 793 nm in red and near-infrared region. Bulk heterojunction solar cells with DTPA–BDPs as electron donor and PC61BM as electron acceptor exhibited photovoltaic properties with a power conversion efficiency of 0.77%, an open-circuit voltage of 0.70 V. 相似文献
109.
110.
Benren Liao Libo Ruan Min Shi Nian LiLiang Chang Leping LiuFan Yang Jie Tang 《Tetrahedron letters》2014
An efficient method for preparation of 3-formyl-2-arylbenzo[b]furan derivatives 4 from 3-chloro-2-(2-methoxyaryl)-1-arylprop-2-en-1-one 2 was developed, and the desired product was obtained in good to excellent yields. By converting 2-(2-methoxyphenyl)-3-oxo-3-phenylpropanal 1 to 2, the regioselectivity problem occurring in the reaction when using 1 as the starting material was successfully avoided. Furthermore, a one-pot procedure for the successive demethylation, cyclization, and hydrolysis was evolved, although the intermediate 3-(dibromomethyl)-2-phenylbenzo[b]furan 3a could be isolated. A plausible mechanism was proposed based on some in situ investigations. 相似文献