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Chinese Physics Letters 2014年第4期31卷 193-196页

作者： REN Jun-Feng YUAN Xiao-Bo hu gui-Chao College of Physics and Electronics Shandong Normal University Jinan 250014

We theoretically investigate the electronic structure and spin polarization properties of Na-doped meridianal tris（S-hydroxyquinoline） aluminum （Alq3） by first principles calculations. It is found that the spin density is distributed mainly in the Alq3 part in the Alq3：Na complex. Electron charge transfer takes place from the Na atom to the Alq3 molecule, which induces asymmetric changing of the molecule bond lengths, thus the spin density distribution becomes asymmetric. Spin polarization of the complex originates from the preferable filling of the spin-split nitrogen and carbon p-orbitals because of the different bond length changes of the Aiq3 molecule upon Na doping.

关键词： SPIN polarization ELECTRONIC structure SODIUM -- Spectra SEMICONDUCTOR doping HYDROXYQUINOLINE CHARGE exchange

Visible-Light Photoredox-Catalyzed Hydrodecarboxylation and Deuterodecarboxylation of Fatty Acids

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Chinese Journal of Chemistry 2022年第16期40卷 1903-1908页

作者： Yuan-Li Sun Fang-Fang Tan Rong-gui hu Chun-Hong hu Yang Li Center for Organic Chemistry Frontier Institute of Science and TechnologyXi'an Jiaotong UniversityXi'anShaanxi710054 China

We develop an efficient visible-light photoreodox-catalyzed hydrodecarboxylation and deuterodecarboxylation of fatty acids for alkanes and deuterium *** key to the efficient transformation should attribute to the co-catalysis of the suitable methoxy substituted acridine photocatalyst(Mes-1,3,6,8-tetramethoxy-Acr-3″,5″-dimethoxy-Ph)and the hydrogen atom transfer catalyst 4′,4′-dimethyl diphenyldisulfane,possibly via facilitating of quenching the active alkyl radicals to overcome the competitive homocoupling products,olefins via the disproportionation,cracking products via the C—C bondβ-scission.

关键词： Photocatalysis Fatty acids Hydrodecarboxylation Deuterodecarboxylation Alkanes

Effect of Carrier Differences on Magnetoresistance in Organic and Inorganic Spin Valves

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Chinese Physics Letters 2012年第6期29卷 261-264页

作者： YUAN Xiao-Bo REN Jun-Feng hu gui-Chao College of Physics and Electronics Shandong Normal UniversityJinan 250014

Magnetoresistance in the structure of ferromagnetic/nonmagnetic/ferromagnetic spin valves are studied theoretically from the spin diffusion theory and Ohm's *** nonmagnetic layer could be an organic or inorganic *** mobility and the spin-flip time in organic semiconductors are different from those in inorganic semiconductors,and effects of these differences on the magnetoresistance in organic and inorganic spin valves are *** the calculation,it is found that the magnetoresistance in inorganic spin valves is higher than that in organic spin *** of the conductivity matching and spin-dependent interfacial resistances between ferromagnetic and nonmagnetic layers,thickness of the nonmagnetic layer,and the bulk spin polarization of the ferromagneticlayer on the magnetoresistance are also discussed.

关键词： inorganic resistance ferromagnetic

Molecular Characterization and Expression Analysis of S1 self-incompatibility Locus-linked Pollen 3.15 Gene in Citrus reticulata

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Journal of Integrative Plant Biology 2013年第5期55卷 443-452页

作者： Hong Xia Miao Zi Xing Ye Yong hua Qin gui Bing hu College of Horticulture South China Agricultural University State Key Laboratory for Conservation and Utilization of Subtropical Agro-bioresources South China Agricultural University Key Laboratory of Biology and Genetic Improvement of Horticultural Crops-South China Ministry of Agriculture

Gametophytic self-incompatibility （GSI） is controlled by a highly polymorphic locus called the S-locus, which is an important factor that can result in seedless fruit in Citrus. The S 1 self-incompatibility locus-linked pollen 3.15 gene （S1-3.15） belongs to a type of S locus gene. The role of S1-3.15 in the SI reaction of Citrus has not yet been reported. In this study, full-length sequences of cDNA and DNA encoding the S1-3.15 gene, referred to as CrS1-3.15 , were isolated from ‘Wuzishatangju’ （Self-incompatibility, SI） and ‘Shatangju’ （Self-compatibility, SC） . The predicted amino acid sequences of CrS1-3.15 between ‘Wuzishatangju’ and ‘Shatangju’ differ by only three amino acids. Compared to ‘Wuzishatangju’, three bases were substituted in the genomic DNA of CrS1-3.15 from ‘Shatangju’. Southern blot results showed that one copy of CrS1-3.15 existed in the genomic DNA of both ‘Wuzishatangju’ and ‘Shatangju’. The expression level of the CrS1-3.15 gene in the ovaries of ‘Shatangju’ was approximately 60-fold higher than that in the ovaries of ‘Wuzishatangju’. When ‘Wuzishatangju’ was cross-pollinated, the expression of CrS1-3.15 was upregulated in the ovaries at 3d, and the highest expression levels were detected in the ovaries at 6d after cross-pollination of ‘Wuzishatangju’ × ‘Shatangju’. To obtain the CrS1-3.15 protein, the full-length cDNA of CrS1-3.15 genes from ‘Wuzishatangju’ and ‘Shatangju’ was successfully expressed in Pichia pastoris. Pollen germination frequency of ‘Wuzishatangju’ was inhibited significantly with increasing CrS1-3.15 protein concentrations from SI ‘Wuzishatangju’.

关键词： Citrus reticulata expression analysis pollen germination S1 self-incompatibility locus-linked pollen 3.15 gene self-compatibility self-incompatibility.

Magnitude-frequency relationship of debris flows in the Jiangjia Gully, China

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Journal of Mountain Science 2019年第6期16卷 1289-1299页

作者： GAO Yan-chao CHEN Ning-sheng hu gui-sheng DENG Ming-feng Key Laboratory of Mountain Hazards and Land Surface Process Institute of Mountain Hazards and EnvironmentCASChengdu 610041China Chengdu Center China Geological SurveyChengdu 610081China University of Chinese Academy of Sciences Beijing 100049China

The magnitude-frequency(MF) relationship of debris flows is the basis for engineering designs and risk quantification. However, because of the lack of debris flow monitoring data, research progress in this area has been relatively slow. The MF relationship of debris flows in Jiangjia Gully, Yunnan Province was evaluated based on a regression analysis of 178 debris flow events that occurred from 1987-2004. The magnitude-cumulative frequency(MCF) relationship of the debris flows in the Jiangjia Gully is consistent with the linear logarithmic transformation function. Moreover, observed data for debris flows in hunshui Gully of Yunnan Province and huoshao Gully, Liuwan Gully, and Niwan Gully of Gansu Province were used to verify the function. The results showed that the MCF relationship of highfrequency debris flows is consistent with the power law equation, although the regression coefficients in the equation are considerably different. Further analysis showed a strong correlation between the differences in the constants and the drainage area and daily maximum precipitation.

关键词： Debris flow Magnitude Cumulative frequency Drainage area Precipitation Jiangjia Gully

Effect of clay content to the strength of gravel soil in the source region of debris flow

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Journal of Mountain Science 2018年第10期15卷 2320-2334页

作者： CHEN Ning-sheng GAO Yan-chao Yang Cheng-lin hu gui-sheng Key Laboratory of Mountain Hazards and Land Surface Process Institute of Mountain Hazards and EnvironmentCASChengdu 60041China Chengdu Center China Geological SurveyChengdu 610081China University of Chinese Academy of Sciences Beijing 100049China

The production of runoff in the source area of a debris flow is the consequence of a reduction in soil strength. Gravel soil is widely distributed in the source region, and the influence of its clay content on soil strength is one of the important questions regarding the formation mechanism of debris flows. In this paper, the clay content in gravel soil is divided into groups of low clay content(1%, 2, 5%), moderate clay content(3.75%, 5.00%, 6.25%, 7.5%) and high clay content(10.0%, 12.5%, 15%). Tests of the unconsolidated undrained shear strength and consolidated drained shear strength were performed. The unconsolidated undrained shearing(UU) experiment simulates the rapid shear failure of loose gravel soil under the conditions of brief heavy rainfall. The consolidated drained shearing(CD) experiment simulates creep failure of consolidated sediment during extended rainfall. The pore water pressure first increased and then decreased as the clay content increased, and the increase in pore pressure was relatively high in the gravel soil sample when the clay content is in the range of 3.25-7.50%, and stress in the gravel soil is relatively low for a moderate clay content. Gravelly soils with a moderate clay content are moreprone to debris-flow initiation. This paper presents a mathematical formula for the maximum shear stress and clay content of gravel soil under two conditions. The key processes whereby the soil fails and triggers a debris flow—volume contraction of soil, expansion of clay soil, and rise of pore pressure―cause reductions in the soil friction force and enhancement of the water content in the clay particles, and subsurface erosion of soil reduces the soil viscosity, which eventually reduces the soil strength so that the soil loses its stability, liquefies and generates a debris flow.

关键词： Debris flows Gravel soil Clay content Maximum shear stress Pore water pressure

Dynamic Theory of Die Swell for Entangled Polymeric Liquids in Tube Extrusion： Correlations of Total and Ultimate Extrudate Swell Effects to Growth Time, Shear Stress and Aspect Ratio Under the Free States

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Chinese Journal of Chemical Physics 2008年第1期21卷 55-68页

作者： Jing Zhao Ming-shi Song Chang-wei Zhu gui-xian hu Ke-jian Wang Da-ming Wu School of Mechanical and Electrical Engineering Belting University of Chemical and TechnologyBeijing 100029 China School of Materials Science and Engineering Beifing University of Chemical and TechnologyBeijing 100029 China

The dynamic theory of die swell deduced in a previous paper was extensively applied to study the extrudate swelling behaviors of two entangled polymeric liquids （HDPE and PBD） in a simple shear flow at steady shear stress. The mechanism and dynamics for the recoils and the recoveries of viscoelastic strains in the extrudate were investigated under the free recovery and dynamic states. It was found that in the course of recovery the free recoil and the growth of die swell in the extrudate may be divided into two recovery regions （instantaneous and delayed regions） and three growth stages （instantaneous, delayed, and ultimate extrudate swelling stages）. The free recoil and the extrudate swelling behaviors may be expressed as a function of shear stress. The correlations of instantaneous, delayed, total and ultimate extrudate swell effects to the molecular parameters and the operational variables in the simple shear flow at steady shear stress were derived from the dynamic theory of die swell. Also, two sets of new universal equations on the total extrudate swelling effect （TESE） and ultimate extrudate swelling effect （UESE） were deduced. The first is the universal equation of the logarithmic correlation between the TESE and the growth time under the free and dynamic states; the second is the universal equation of the logarithmic correlation between the UESE and the operational variables under the free and equilibrium states. The first equation was verified by experimental data of PBD with different molecular weights at different operational variables. The second equation was verified by experimental data of HDPE at two temperatures and different operational variables. An excellent agreement result was obtained. The excellent agreement shows that the two universal equations can be used directly to predict the correlations of the TESE and UESE to the growth time, the molecular parameters, and the operational variables under the dynamic and equilibrium states.

关键词： Die swell Entanglement Viscoelastic recoil

A Universal Reduced Rupture Creep Approach for Failure Behavior of Aged Glass Polymers from the Rupture Creep Compliance by the Unified Master Prediction of Long Term Short Term Test of Curved Extrapolation

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Chinese Journal of Chemical Physics 2012年第5期25卷 552-562,I0003页

作者： Guang-jun Song Da-ming Wu Wei-yue Song Ming-shi Song gui-xian hu School of Mechanical and Electrical EnEineering Beijing University of Chemical Technology BeLying100029 China Department of Polymeric Material Science and Engineering Beijing Institute of Petrochemical Tech-nology Beijing 102617 China School of Materials Science and Engineering Beijing University of Chemical Technology Beijing100029 China

The prediction of long term failure behaviors and lifetime of aged glass polymers from the short term tests of reduced rupture creep compliance （or strain） is one of difficult problems in polymer science and engineering. A new ＂universal reduced rupture creep approach＂ with exact theoretical analysis and computations is proposed in this work. Failure by creep for polymeric material is an important problem to be addressed in the engineering. A universal equation on reduced extensional failure creep compliance for PMMA has been derived. It is successful in relating the reduced extensional failure creep compliance with aging time, temperature, levels of stress, the average growth dimensional number and the parameter in K-W-W function. Based on the universal equation, a method for the prediction of failure behavior, failure strain criterion, failure time of PMMA has been developed which is named as a universal ＂reduced rupture creep approach＂. The results show that the predicted failure strain and failure time of PMMA at different aging times for different levels of stress are all in agreement with those obtained directly from experiments, and the proposed method is reliable and practical. The dependences of reduced extensional failure creep compliance on the conditions of aging time, failure creep stress, the structure of fluidized-domain constituent chains are discussed. The shifting factor, exponent for time-stress superposition at different levels of stress and the shifting factor, exponent for time-time aging superposition at different aging time are theoretically defined respectively.

关键词： Reduced extensional failure creep compliance Extensional failure Predictionof failure strain and time PMMA Shifting factor Shifting exponent

Involvement of methylation-associated silencing of formin 2 in colorectal carcinogenesis

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World Journal of Gastroenterology 2018年第44期24卷 5013-5024页

作者： Dao-Jiang Li Zhi-Cai Feng Xiao-Rong Li gui hu Department of Gastro-intestinal Surgery the Third Xiangya Hospital Central South University Department of Burns and Plastic Surgery the Third Xiangya Hospital Central South University

AIM To investigate whether promoter methylation is re-sponsible for the silencing of formin 2 （ FMN2） in colorectal cancer （CRC） and to analyze the association between FMN2 methylation and *** frst identifed the expression levels and methylation levels of FMN2 in large-scale human CRC expression data-sets, including GEO and TCGA, and analyzed the relation-ship between the expression and methylation levels. Then, the methylation levels in four CpG regions adjacent to the FMN2 promoter were assessed by MethylTarget？ assays in CRC cells and in paired colorectal tumor samples and adjacent nontumor tissue samples. Furthermore, we inhibited DNA methylation in CRC cells with 5-Aza-2’-deoxycytidine and assessed the expression of FMN2 by qRT-PCR. Last, the association between FMN2 methylation patterns and clinical indicators was *** statistically significant downregulation of FMN2 ex-pression in large-scale human CRC expression datasets was found. Subsequent analysis showed that a high frequency of hypermethylation occurred in the FMN2 gene promoter in CRC tissues; operating characteristic curve analysis revealed that FMN2 gene methylation had a good capability for discriminating between CRC and nontumor tissue samples （AUC = 0.8432, P 〈 0.0001）. MethylTarget？ assays showed that CRC cells and tissues displayed higher methylation of these CpG regions than nontumor tissue samples. Correlation analysis showed a strong inverse correlation between methylation and FMN2 expression, and the inhibition of DNA methylation with 5-Aza significantly increased endogenous FMN2 expression. Analysis of the association between FMN2 methylation patterns and clinical indicators showed that FMN2 methylation was signifcantly associated with age, N stage, lymphovascular invasion, and pathologic tumor stage. Notably, the highest methylation of FMN2 occurred in tissues from cases of early-stage CRC, including cases with no regional lymph node metastasis （N0）, cases in stag

关键词： Formin 2 Colorectal cancer Methylation Methylation-associated silencing Early-stage cancer

Hydroxylation of Benzene to Phenol via Hydrogen Peroxide in Hydrophilic Triethylammonium Acetate Ionic Liquid

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Chemical Research in Chinese Universities 2011年第3期27卷 503-507页

作者： hu Xiao-ke Zhu Liang-fang GUO Bin LIU Qiu-yuan LI gui-ying hu Chang-wei Key Laboratory of Green Chemistry and Technology Ministry of Education College of Chemistry Sichuan University Chengdu 610064 P. R. China

A new Fenton-like system in a medium of hydrophilic triethylammonium type of ionic liquid（IL） was used for the hydroxylation of benzene to phenol. The triethylammonium acetate（[Et3NH][CH3COO]） IL exhibited retardation performance for the decomposition of H2O2 and protection performance for the further oxidation of phenol, thus the yield and selectivity to phenol were promoted greatly. The acidity of the system was proved to be an important factor for the selectivity to phenol. The utilization of H2O2 and the selectivity to phenol, as well as the Turnover number（TON） of the catalyst were effectively enhanced by a benzene-[Et3NH][CH3COO] bi-phase system. The catalyst with [Et3NH][CH3COO] IL was recycled with stable catalytic performance.

关键词： Hydrophilic Ionic liquid Fenton-like Hydroxylation