A Statistical Study on Photospheric Magnetic Nonpotentiality of Active Regions and Its Relationship with Flares during Solar Cycles 22-23

A statistical study is carried out on the photospheric magnetic nonpotentiality in solar active regions and its relationship with associated flares. We select 2173 photospheric vector magnetograms from 1106 active regions observed by the Solar Magnetic Field Telescope at Huairou Solar Observing Station, National Astronomical Observatories of China, in the period of 1988-2008, which covers most of the 22nd and 23rd solar cycles. We have computed the mean planar magnetic shear angle (\bar{\Delta\phi}), mean shear angle of the vector magnetic field (\bar{\Delta\psi}), mean absolute vertical current density (\bar{|J_{z}|}), mean absolute current helicity density (\bar{|h_{c}|}), absolute twist parameter (|\alpha_{av}|), mean free magnetic energy density (\bar{\rho_{free}}), effective distance of the longitudinal magnetic field (d_{E}), and modified effective distance (d_{Em}) of each photospheric vector magnetogram. Parameters \bar{|h_{c}|}, \bar{\rho_{free}}, and d_{Em} show higher correlation with the evolution of the solar cycle. The Pearson linear correlation coefficients between these three parameters and the yearly mean sunspot number are all larger than 0.59. Parameters \bar{\Delta\phi}, \bar{\Delta\psi}, \bar{|J_{z}|}, |\alpha_{av}|, and d_{E} show only weak correlations with the solar cycle, though the nonpotentiality and the complexity of active regions are greater in the activity maximum periods than in the minimum periods. All of the eight parameters show positive correlations with the flare productivity of active regions, and the combination of different nonpotentiality parameters may be effective in predicting the flaring probability of active regions.Comment: 20 pages, 5 figures, 4 tables, accepted for publication in Solar Physic

Solvation-Induced Onsager Reaction Field Rather than Double Layer Field Controls CO2 Reduction on Gold

The selectivity and activity of the carbon dioxide reduction reaction (CO2R) are sensitive functions of the electrolyte cation. By measuring the vibrational Stark shift of in-situ generated CO on Au in the presence of alkali cations, we quantify the total electric field present during turnover and deconvolute this field into contributions from 1) the electrochemical Stern layer and 2) the Onsager, or solvation-induced, reaction field. The magnitude of the Onsager field is shown to be on the same order as the Stern layer field (∼10 MV/cm) but follows an opposite trend with cation, increasing from Li+< Na+++≈Cs+. Contrary to theoretical reports,CO2R kinetics are not correlated with the Stern field but instead are controlled by the strength of the Onsager reaction field with Cs+ as an exception. Spectra of interfacial water as a function of cation show that Cs+ induces a change in the interfacial water structure correlated with a dramatic drop in CO2R activity, highlighting the importance of cation-dependent interfacial water structure on reaction kinetics. These findings show that both the Onsager reaction field and interfacial solvation structure must be explicitly considered for accurate modeling of CO2R reaction kinetics.</div

溶液和熔化状态下分子间的能量传递

通过二维红外光谱研究了GdmSCN／KSCN=1／1，GdmSCN／KS^13CN=1／1和GdmSCN／KS^13C^15N=1／1三种混合晶体在熔融和溶液状态下的共振和非共振的分子间振动能量传递的性质．在这些样品中，给体／受体的能量差越大，能量传递越慢．而能量传递的快慢与拉曼光谱无关．非共振能量传递与给体／受体的能量差的关系不能用声子补偿的机理来描述．相反，它们的关系却可以用退相位机理来定量描述．在熔融状态下，共振和非共振能量速率与温度的依赖关系也与退相位机理的预测相符合．这一系列的结果表明只要分子的运动（平动和转动）远远快于非共振能量传递速率，那么退相位机理不仅在溶液中占主导，而且在熔融状态下（纯液体，不含溶剂）也占主导

溶液和熔化状态下分子间的能量传递

通过二维红外光谱研究了GdmSCN／KSCN=1／1，GdmSCN／KS^13CN=1／1和GdmSCN／KS^13C^15N=1／1三种混合晶体在熔融和溶液状态下的共振和非共振的分子间振动能量传递的性质．在这些样品中，给体／受体的能量差越大，能量传递越慢．而能量传递的快慢与拉曼光谱无关．非共振能量传递与给体／受体的能量差的关系不能用声子补偿的机理来描述．相反，它们的关系却可以用退相位机理来定量描述．在熔融状态下，共振和非共振能量速率与温度的依赖关系也与退相位机理的预测相符合．这一系列的结果表明只要分子的运动（平动和转动）远远快于非共振能量传递速率，那么退相位机理不仅在溶液中占主导，而且在熔融状态下（纯液体，不含溶剂）也占主导

Hypolipidemic, anti-inflammatory, and anti-atherosclerotic effects of tea before and after microbial fermentation

BACKGROUND Microbial fermentation significantly affects the flavor and efficacy of tea. It is generally believed that fermented tea is more effective in lowering lipids, while unfermented tea can more effectively inhibit inflammation. However, there is not sufficient evidence to support this claim. To systematically compare the hypolipidemic, anti-inflammatory, and anti-atherosclerotic effects of tea before and after microbial fermentation, hyperlipidemic rats and inflammatory injury cells were treated with Monascus purpureus-fermented pu-erh tea water extract (MPT) and sun-dried green tea water extract (SGT), respectively. RESULTS MPT, with higher levels of theabrownins, flavonoids, gallic acid (GA), and lovastatin, was more effective in reducing serum triglyceride (TG), total cholesterol (TC), low-density lipoprotein cholesterol (LDL-C), and inflammatory cytokines (TNF-α, IL-1β, and IL-6), while SGT, with higher levels of tea polyphenols, amino acids, (-)-epigallocatechin gallate (EGCG), and theaflavins, was more effective in increasing serum high-density lipoprotein cholesterol (HDL-C) in hyperlipidemic rats. The foam cells on the arterial wall of the rats in the MPT group were visibly less, and the thrombosis time was longer than that in the SGT group. Cell experiments showed that MPT was more effective in protecting endothelial cells from damage than SGT. CONCLUSION Surprisingly, Monascus purpureus-fermented pu-erh tea not only had better hypolipidemic and anti-atherosclerotic effects than its raw material (sun-dried green tea), but also was superior in anti-inflammatory effects to the latter, which was possibly attributable to the great changes in functional ingredients during microbial fermentation

Comparison Studies on Sub-Nanometer-Sized Ion Clusters in Aqueous Solutions: Vibrational Energy Transfers, MD Simulations, and Neutron Scattering

In this work, MD simulations with two different force fields, vibrational energy relaxation and resonant energy transfer experiments, and neutron scattering data are used to investigate ion pairing and clustering in a series of GdmSCN aqueous solutions. The MD simulations reproduce the major features of neutron scattering experimental data very well. Although no information about ion pairing or clustering can be obtained from the neutron scattering data, MD calculations clearly demonstrate that substantial amounts of ion pairs and small ion clusters (subnanometers to a few nanometers) do exist in the solutions of concentrations 0.5 M*, 3 M*, and 5 M* (M* denotes mole of GdmSCN per. 55.55 mole of water). Vibrational relaxation experiments suggest that significant amounts of ion pairs form in the solutions. Experiments measuring the resonant energy transfers among the thiocyanate anions in the solutions suggest that the ions form clusters and in the clusters the average anion distance is 5.6 angstrom (5.4 angstrom) in the 3 M* (5 M*) Gdm(-D)SCN/D2O solution