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Origin of the Blue Luminescence in Porous Anodic Alumina Films Formed in Oxalic Acid Solutions

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Chinese Physics Letters 2003年第5期20卷 713-716页

作者： GAOTao MENGGuo-wen ZHANGLi-de InstituteofSolidStatePhysics ChineseAcademyofSciencesPOBox1129Hefei230031

Photoluminescence spectra of porous anodic alumina (PAA) films formed in oxalic acid solutions show a blue emission band peaked around 470 nm, in which the corresponding excitation bands locate at 248 nm, 304 nm, and 360 nm, respectively. With the help of ascertaining the mechanism of this blue luminescence, the roles of the oxalic ions on the optical properties of the PAA films was discussed by using optical absorption spectra. It is suggested that the oxalic impurities with different existing or distributing forms would play important roles on the optical properties of PAA films. The 470-nm blue luminescence band could be attributed to the incorporated oxalic impurities rather than the F+ centres existed in the PAA films formed in oxalic acid solutions.

关键词：氧化铝薄膜光致发光光谱多孔渗水蓝光草酸薄膜生长

Mechanism of Bragg Diffraction-Assisted Light Extraction in GaN-based Light-Emitting Diodes Based on a Self-Consistent Model

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Communications in Theoretical Physics 2009年第9期52卷 545-548页

作者： LIU wen-de GAN Zi-Zhao National Institute of Metrology Beijing 100013 China School of Physics and State Key Laboratory for Artificial Microstructures and Mesoscopic Physics Peking University Beijing 100871 China

By introducing the distribution of the light energy density in GaN-based light-emitting diode (LED),theLED model based on the incoherent regime and the light extraction efficiency are *** energy density asa function of the angle of incidence is calculated to demonstrate the mechanism of the light *** deviationbetween the tendencies of the transmissivity of the output layer and the extraction efficiency is also demonstrated.

关键词： light-emitting diodes extraction efficiency Bragg diffraction photonic crystals

Quantitative and qualitative research on service quality evaluation system in NGN

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The Journal of China Universities of Posts and Telecommunications 2009年第5期16卷 71-77页

作者： LIU Lu ZHOU wen-an SONG Jun-de ICT and SSME Center Beijing University of Posts and Telecommunications Beijing 100876 China

With the development of next generation network （NGN）, reasonable service quality evaluation is essential in network management. Based on NGN service characteristics, this article presents a comprehensive service quality evaluation system from two perspectives： quantitative and qualitative. From the quantitative point of view, this article brings forward the normalized service level achievement function （NSLA function） at technical layer. Also, with mean opinion score （MOS） mode, it proposes customer satisfaction assessment methods at customer perception layer. From the qualitative perspective, a hierarchical model is established, which forms mapping relations from the upper customer perception to the lower service quality parameters, and then the influence of different service parameters on customer satisfaction degree can b＇e denoted by the fuzzy analysis hierarchy process （FAHP） algorithm. Quantitative and qualitative evaluations together form a comprehensive solution which is universal, customer-oriented and flexible. demonstrated by the representative voice service, the proposed system is proved reliable and applicable to service evaluation in NGN.

关键词： customer satisfaction degree key quality indicator (KQI) NSLA function quality of experience index (QoE index) FAHP

Biological Cycles of Mineral Elements in a Young Mixed Stand in Abandoned Mining Soils

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Journal of Integrative Plant Biology 2007年第9期49卷 1284-1293页

作者： Da-Lun Tian wen-Hua Xiang wen-de Yan wen-Xing Kang Xiang-wen deng Zhu Fan Research Section of Ecology Central-South University of Forestry & Technology Changsha 410004 China

Phytoremediation as a sustainable and inexpensive technology based on the removal of pollutants from the environment by plants is becoming an increasingly important objective in plant research. In this study, biological cycles of five nutrient elements （N, P, K, Ca, and Mg） and eight heavy metal elements （Fe, Cu, Zn, Mn, Cd, Ni, Pb and Co） were examined in young paniculed goldraintree （Koelreuteria paniculata Laxm） and common elaeocarpus （Elaeocarpus decipens） mixed stands in an abandoned mining area. We found that after vegetation restoration in abandoned mining areas, the organic matter and concentrations of nutrient elements were significantly increased and the heavy metal elements were significantly decreased, the annual retention, uptake and return were 75.0, 115.4, and 40.3 kg/hm^2 for nutrient elements, and 1 878.0, 3 231.0 and 1 353.0 g/hm^2 for heavy metal elements, respectively, with the utilization coefficient, cycling coefficient and turnover rate of 0.92, 0.35 and 0.32 for nutrient elements, and 1.24, 0.42 and 1.92 for heavy metal elements, respectively. Our results suggested that the vegetation restoration in abandoned mining areas had significant effects in improving environmental conditions, enhancing soil available nutrients, and ensuring human health.

关键词： abandoned mining areas biological cycle common elaeocarpus (Elaeocarpus decipens) heavy metal elements mixed stand paniculed goldraintree (Koelreuteria paniculata).

Integrated pest management programme for cereal blast fungus Magnaporthe oryzae

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Journal of Integrative Agriculture 2022年第12期21卷 3420-3433页

作者： ZHANG Hai-feng Tofazzal ISLAM LIU wen-de department of Plant Pathology College of Plant ProtectionNanjing Agricultural University/Key Laboratory of Integrated Management of Crop Diseases and Pests of Ministry of EducationNanjing 210095P.R.China Institute of Biotechnology and Genetic Engineering Bangabandhu Sheikh Mujibur Rahman Agricultural UniversityGazipur 1706Bangladesh State Key Laboratory for Biology of Plant Diseases and Insect Pests Institute of Plant ProtectionChinese Academy of Agricultural SciencesBeijing 100193P.R.China

Magnaporthe oryzae,the causal agent of blast diseases,is a destructive filamentous fungus that infects many plants including most economically important food crops,rice,wheat,pearl millet and finger *** oryzae has numerous pathotypes because of its high host-specificity in the *** Oryza pathotype(MoO)of *** is the most devastating pathogen of rice,causing 10–30%yield loss in the *** the other hand,the Triticum pathotype(MoT)causes blast disease in wheat,which is now a serious threat to wheat production in some South American countries,Bangladesh and *** of low fungicide efficacy against the blast diseases and lack of availability of resistant varieties,control of rice and wheat blast diseases is ***,an integrated management programme should be adopted to control these two diseases in the ***,we introduced and summarized the classification,geographical distribution,host range,disease symptoms,biology and ecology,economic impact,and integrated pest management(IPM)programme of both rice and wheat blast diseases.

关键词： rice blast wheat blast Magnaporthe oryzae integrated pest management

Preparation of activated carbon from sunflower straw through H_(3)PO_(4) activation and its application for acid fuchsin dye adsorption

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Water Science and Engineering 2023年第2期16卷 192-202页

作者： wen-de Zhao Li-ping Chen Yan Jiao College of Chemistry and Environmental Science Inner Mongolia Normal UniversityHohhot 010022China Inner Mongolia Key Laboratory of Environmental Chemistry Hohhot 010022China

With the development circular economy, the use of agricultural waste to prepare biomass materials to remove pollutants has become a research hotspot. In this study, sunflower straw activated carbon (SSAC) was prepared by the one-step activation method, with sunflower straw (SS) used as the raw material and H3PO4 used as the activator. Four types of SSAC were prepared with impregnation ratios (weight of SS to weight of H3PO4) of 1:1, 1:2, 1:3, and 1:5, corresponding to SSAC1, SSAC2, SSAC3, and SSAC4, respectively. The adsorption process of acid fuchsin (AF) in water using the four types of SSAC was studied. The results showed that the impregnation ratio significantly affected the structure of the materials. The increase in the impregnation ratio increased the specific surface area and pore volume of SSAC and improved the adsorption capacity of AF. However, an impregnation ratio that was too large led to a decrease in specific surface area. SSAC3, with an impregnation ratio of 1:3, had the largest specific surface area (1 794.01 m2/g), and SSAC4, with an impregnation ratio of 1:5, exhibited the smallest microporosity (0.052 7 cm3/g) and the largest pore volume (2.549 cm3/g). The adsorption kinetics of AF using the four types of SSAC agreed with the quasi-second-order adsorption kinetic model. The Langmuir isotherm model was suitable to describe SSAC3 and SSAC4, and the Freundlich isotherm model was appropriate to describe SSAC1 and SSAC2. The result of thermodynamics showed that the adsorption process was spontaneous and endothermic. At 303 K, SSAC4 showed a removal rate of 97.73% for 200-mg/L AF with a maximum adsorption capacity of 2 763.36 mg/g, the highest among the four types of SSAC. This study showed that SAAC prepared by the H3PO4-based one-step activation method is a green and efficient carbon material and has significant application potential for the treatment of dye-containing wastewater.

关键词： Acid fuchsin Activated carbon Adsorption Sunflower straw Phosphoric acid activation Impregnation ratio

Geochemical identification of a source rock affected by migrated hydrocarbons and its geological significance:Fengcheng Formation,southern Mahu Sag,Junggar Basin,NW China

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Petroleum Science 2024年第1期21卷 100-114页

作者： wen-Long Dang Gang Gao Xin-Cai You Ke-Ting Fan Jun Wu de-wen Lei wen-Jun He Yong Tang State Key Laboratory of Petroleum Resource and Prospecting China University of Petroleum(Beijing)Beijing102249China School of GeoSciences China University of Petroleum(Beijing)Beijing102249China Exploration&development Institute Xinjiang Oil Field CompanyKaramay834000XinjiangChina

The Fengcheng Formation is a crucial source rock and the primary reservoir for oil accumulation in the Mahu *** oils are distributed throughout the Fengcheng Formation,ranging from the edge to the interior of the sag in the southern Mahu *** crude oils originate from in-situ source rocks in shallowly buried areas and the inner deep *** migration,the crude oil from the inner deep sag affects the source rocks close to carrier beds,leading to changes in the organic geochemical characteristics of the source *** changes might alter source rock evaluations and oil-source *** on data such as total organic carbon(TOC),Rock-Eval pyrolysis of source rocks,and gas chromatography-mass spectrometry(GC-MS)of the saturated fraction,and considering the geological characteristics of the study area,we define the identification characteristics of source rock affected by migrated hydrocarbons and establish the various patterns of influence that migrated hydrocarbons have on the source rock of the Fengcheng Formation in the southern Mahu *** source rocks of the Fengcheng Formation are mostly fair to good,containing mainly Type II organic matter and being thermally mature enough to generate *** rocks affected by migrated hydrocarbons exhibit relatively high hydrocarbon contents(S1/TOC>110 mg HC/g TOC,Extract/TOC>30%,HC:hydrocarbon),relatively low Rock-Eval Tmax values,and relatively high tricyclic terpane contents with a descending and mountain-shaped ***,biomarker composition parameters indicate a higher thermal maturity than in-situ source *** a comparison of the extract biomarker fingerprints of adjacent reservoirs and mudstones in different boreholes,three types of influence patterns of migrated hydrocarbons are identified:the edge-influence of thin sandstone-thick mudstone,the mixed-influence of sandstone-mudstone interbedded,and the full-influence of thick sandstone-thin *** finding reminds

关键词： Organic geochemistry Source rock Influence of migrated hydrocarbons Fengcheng Formation Southern Mahu Sag

Synthesis of Novel 1-Alkyl-2-chloro(alkoxy)-1H-indole 3-Carbaldehyde Oximes and Oxime-ethers(esters) derivatives

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Chemical Research in Chinese Universities 2009年第4期25卷 465-473页

作者： GAO wen-tao GAO de-peng GUO Hui Institute of Superfine Chemicals Bohai University Jinzhou 121000 P. R. China

A convenient synthesis of 1-alkyl-2-chloro-1H-indole-3-carbaldehyde oximes（5a―5d） and 1-alkyl-2-phenoxy-1H-indole-3-carbaldehyde oximes（6a―6d） from 2-indolone was completed via the Vilsmeier-Haack reac-tion,with N-alkylation and oximation as the key *** improved one-pot method for the synthesis of 1-alkyl-2-alkoxy-1H-indole-3-carbaldehyde oximes（7a―7h） from 1-alkyl-2-chloro-1H-indole-3-carbaldehydes（3a―3d） was *** Williamson reactions and esterification reactions were performed and the oxime-ethers and oxime-esters were synthesized,*** new synthesized compounds（3a―11d） were characterized by 1H NMR,IR,MS,and elemental analysis.

关键词： Oxime Indole Vilsmeier-Haack reaction Williamson reaction One-pot method

Structure of Rotating Neutron Stars in Uniform Strong Magnetic Field

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Communications in Theoretical Physics 2007年第4期47卷 653-657页

作者： wen de-Hua CHEN Wei LIU Liang-Gang department of Physics South China University of Technology Guangzhou 510641 China department of Physics Jinan University Guangzhou 510632 China The Faculty of Information Technology Macao University of Science and Technology Macao China

Properties and deformations of the rotating neutron stars in uniform strong magnetic field are calculated. The magnetic field will soften the equation of state of the neutron star matters and make an obvious effect on the structure of the rotating neutron star. If the magnetic field is superstrong （B=10^17 T）, the mass, radius, and the deformation will become smaller effectively.

关键词： structure neutron star strong magnetic field