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Generalizations of Several Identities Related to Mercier's
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作者 胡廷锋 《Chinese Quarterly Journal of Mathematics》 CSCD 2001年第3期105-110,共6页
The purpose of this paper is to establish sev eral identities containing Gaussian binomial coefficient. These results generali ze several Mercier's results. Key words:Gaussian binomial coefficient; identity; the ... The purpose of this paper is to establish sev eral identities containing Gaussian binomial coefficient. These results generali ze several Mercier's results. Key words:Gaussian binomial coefficient; identity; the functio n A(T,T 2,...,T n)culating eige nvalues of auto-correlation matrix of the physical control force of actuators. T he optimization algorithm calculating the optimal actuator placement is then put forward via the minimization of an energy criterion, which is chosen as the con trol index. Numerical examples show the effectiveness of the proposed method. 展开更多
关键词 modal space control auto-correlation matrix optimal design.
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1,1'-Methylenediimidazolium-Based Multiple Hydrogen-Bond Donor Catalysts Facilitate the Cycloaddition of CO_(2) with Epoxides under Atmospheric Pressure
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作者 Chen Xuewei Yu Fangcai Tian Chuanhong 《有机化学》 SCIE CAS CSCD 北大核心 2024年第10期3198-3205,共8页
The quest for innovative hydrogen-bond donor(HBD)catalysts has led to a significant advancement in the field of organic synthesis.Considering the electron-withdrawing strength of imidazolium cations and the spatial re... The quest for innovative hydrogen-bond donor(HBD)catalysts has led to a significant advancement in the field of organic synthesis.Considering the electron-withdrawing strength of imidazolium cations and the spatial requirements of hydrogen bond donors,a novel HBD catalyst based on the 1,1'-methylenediimidazolium scaffold by bridging two imidazolium cations with methylene was developed.The 1,1'-methylenediimidazolium-based catalysts exhibit excellent performance in the cycloaddition reaction of CO_(2) and epoxides,achieving up to 99% yield and 99%selectivity under mild conditions(atmospheric pressure,80℃ for 12 h,with 1 mol%catalyst).The geometric structure,atomic charge distribution,and synergistic effect of HBD catalysts were studied in detail through 1H NMR spectroscopy and density functional theory(DFT)calculations.The research results indicate that the protons at positions C2-H,C2'-H,C5-H,and C5'-H on the imidazolium rings,as well as the protons on the bridged methylene,contribute to the formation of multiple hydrogen bonds with appropriate distance and synergistic effects,which are crucial for activating CO_(2) and epoxides.This research highlights the distinctive attributes of 1,1'-methylenediimidazolium-based catalysts and offers valuable insights into the development of highly efficient multiple HBD catalysts. 展开更多
关键词 1 1'-methylenediimidazolium multiple hydrogen-bond donor catalysts cycloaddition of CO_(2) cooperative effects density functional theory(DFT)calculation
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层次逻辑系统论——以哲学与章法学作对应考察 被引量:7
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作者 陈满铭 《渤海大学学报(哲学社会科学版)》 2005年第6期1-7,共7页
逻辑层次,乃由多样的“二元对待”为基础,经“移位与转位”之过程与“‘多’、‘二’、‘一(0)’ 螺旋结构”之终极统合,而形成其完整系统;这不但可由《周易》与《老子》等哲学典籍中找出它的理论根 源,也可从辞章章法结构中寻得它的具... 逻辑层次,乃由多样的“二元对待”为基础,经“移位与转位”之过程与“‘多’、‘二’、‘一(0)’ 螺旋结构”之终极统合,而形成其完整系统;这不但可由《周易》与《老子》等哲学典籍中找出它的理论根 源,也可从辞章章法结构中寻得它的具体呈现。因此本文即从“二元对待”(含“对比与调和”)、“移位与 转位”与“‘多’、‘二’、‘一(0)’螺旋结构”等层面切入,作对应之探讨,以凸显出层次逻辑系统在哲学与章 法学中的纽带作用。 展开更多
关键词 层次逻辑系统 哲学 章法学 元对待(含对比与调和) 移位与转位 “'多’'二’ '一(0)’”螺旋结构 《周易》 《老子》
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Research on Thermodynamic Properties of Polybrominated Diphenylamine by Neural Network 被引量:19
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作者 堵锡华 庄文昌 +1 位作者 史小琴 冯长君 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 2015年第1期59-64,I0001,I0002,共8页
Based on the location of bromine substituents and conjugation matrix, a new substituent po- sition index ~X not only was defined, but also molecular shape indexes Km and electronega- tivity distance vectors Mm of diph... Based on the location of bromine substituents and conjugation matrix, a new substituent po- sition index ~X not only was defined, but also molecular shape indexes Km and electronega- tivity distance vectors Mm of diphenylamine and 209 kinds of polybrominated diphenylamine (PBDPA) molecules were calculated. Then the quantitative structure-property relationships (QSPR) among the thermodynamic properties of 210 organic pollutants and 0X, K3, M29, M36 were founded by Leaps-and-Bounds regression. Using the four structural parameters as input neurons of the artificial neural network, three satisfactory QSPR models with network structures of 4:21:1, 4:24:1, and 4:24:1 respectively, were achieved by the back-propagation algorithm. The total correlation coefficients R were 0.9999, 0.9997, and 0.9995 respectively and the standard errors S were 1.036, 1.469, and 1.510 respectively. The relative mean deviation between the predicted value and the experimental value of Sθ, AfHe and △fGθ- were 0.11%, 0.34% and 0.24% respectively, which indicated that the QSPR models had good stability and superior predictive ability. The results showed that there were good nonlinear correlations between the thermodynamic properties of PBDPAs and the four structural pa- rameters. Thus, it was concluded that the ANN models established by the new substituent position index were fully applicable to predict properties of PBDPAs. 展开更多
关键词 Polybrominated diphenylamine Neural networks Molecular shape index Elec-tronegativity distance vector Substituent position index Thermodynamic properties
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Low temperature molten salt synthesis of porous La_(1-x)Sr_xMn_(0.8)Fe_(0.2)O_3(0≤x≤0.6) microspheres with high catalytic activity for CO oxidation 被引量:4
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作者 黄学辉 牛鹏举 商晓辉 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 北大核心 2016年第8期1431-1439,共9页
A molten salt method was developed to prepare porous La1‐xSrxMn0.8Fe0.2O3 (0≤ x ≤ 0.6) micro‐spheres using hierarchical porous δ‐MnO2 microspheres as a template in eutectic NaNO3‐KNO3. X‐ray diffraction patt... A molten salt method was developed to prepare porous La1‐xSrxMn0.8Fe0.2O3 (0≤ x ≤ 0.6) micro‐spheres using hierarchical porous δ‐MnO2 microspheres as a template in eutectic NaNO3‐KNO3. X‐ray diffraction patterns showed that single phase LaMn0.8Fe0.2O3 with good crystallinity was syn‐thesized at 450℃ after 4 h. Transmission electron microscope images exhibited that the LaMn0.8Fe0.2O3 sample obtained at 450?? after 4 h possessed a porous spherical morphology com‐posed of aggregated nanocrystallites. Field emission scanning electron microscope images indicated that the growth of the porous LaMn0.8Fe0.2O3 microspheres has two stages. SEM pictures showed that a higher calcination temperature than 450?? had an adverse effect on the formation of a po‐rous spherical structure. The LaMn0.8Fe0.2O3 sample obtained at 450?? after 4 h displayed a high BET surface area of 55.73 m2/g with a pore size of 9.38 nm. Fourier transform infrared spectra suggested that Sr2+ions entered the A sites and induced a decrease of the binding energy between Mn and O. The CO conversion with the La1‐xSrxMn0.8Fe0.2O3 (0≤x≤0.6) samples indicated that the La0.4Sr0.6Mn0.8Fe0.2O3 sample had the best catalytic activity and stability. Further analysis by X‐ray photoelectron spectroscopy demonstrated that Sr2+doping altered the content of Mn4+ions, oxygen vacancies and adsorbed oxygen species on the surface, which affected the catalytic performance for CO oxidation. 展开更多
关键词 Molten salt method δ-MnO2 microsphere Porous spherical structure Calcination temperature Carbon monoxide oxidation
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On Triangle Interpolation Approximation of the Double Function 被引量:3
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作者 袁学刚 韩友发 《Chinese Quarterly Journal of Mathematics》 CSCD 2000年第4期61-65,共5页
本文以两组不同的节点构造了一个组合型的二元三角插值多项式算子Lmn(f;x,y),并且研究了二元连续周期函数对这个算子的收敛性及收敛阶的估计等问题。
关键词 double triangle interpolation polymial convergence order converge uniforml?
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Photoelectrochemical degradation of acetaminophen and valacyclovir using nanoporous titanium dioxide 被引量:5
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作者 谢国红 常欣 +2 位作者 Bal Ram Adhikari Sapanbir S.Thind 陈爱成 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 北大核心 2016年第7期1062-1069,共8页
Electrochemically treated nanoporous TiO2 was employed as a novel electrode to assist in the pho- toelectrochemical degradation of acetaminophen and valacyclovir. The prepared electrode was characterized by scanning e... Electrochemically treated nanoporous TiO2 was employed as a novel electrode to assist in the pho- toelectrochemical degradation of acetaminophen and valacyclovir. The prepared electrode was characterized by scanning electron microscopy (SEM) and energy dispersive spectroscopy (EDS). Cyclic voltammetry (CV), Mott-Schottky plots, ultraviolet-visible light (UV-vis) absorbance spec- troscopy, and a total organic carbon (TOC) analyzer were employed to investigate the photoelec- trochemical degradation of acetaminophen and valacyclovir. The results indicated no obvious re- moval of acetaminophen and valacyclovir over 3 h when separate photochemical degradation and electrochemical oxidation were employed. In contrast, acetaminophen and valacyclovir were rapid- ly eliminated via photoelectrochemical degradation. In addition, electrochemically treated nanopo~ rous TiO2 electrodes significantly enhanced the efficacy of the photoelectrochemical degradation of acetaminophen and valacyclovir, by 86.96% and 53.12%, respectively, when compared with un- treated nanoporous TiO2 electrodes. This enhanced performance may have been attributed to the formation of Ti3~, Ti2~, and oxygen vacancies, as well as an improvement in conductivity during the electrochemical reduction process. The effect of temperature was further investigated, where the activation energy of the photoelectrochemical degradation of acetaminophen and valacyclovir was determined to be 9.62 and 18.42 kJ/mol, respectively. 展开更多
关键词 Photoelectrochemical degradationNanoporous titanium dioxideAcetaminophenValacyclovirActivation energy
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The surface wave suppression using the second generation curvelet transform 被引量:11
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作者 郑静静 印兴耀 +2 位作者 张广智 武国虎 张作胜 《Applied Geophysics》 SCIE CSCD 2010年第4期325-335,399,400,共13页
In this paper,we develop a new and effective multiple scale and strongly directional method for identifying and suppressing ground roll based on the second generation curvelet transform.Making the best use of the curv... In this paper,we develop a new and effective multiple scale and strongly directional method for identifying and suppressing ground roll based on the second generation curvelet transform.Making the best use of the curvelet transform's strong local directional characteristics,seismic frequency bands are transformed into scale data with and without noise.Since surface waves and primary reflected waves have less overlap in the curvelet domain,we can effectively identify and separate noise.Applying this method to prestack seismic data can successfully remove surface waves and,at the same time,protect the reflected events well,particularly in the low-frequency band.This indicates that the method described in this paper is an effective and amplitude-preserving method. 展开更多
关键词 Second generation curvelet transform multiscale strong directional characteristics surface wave removal
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Preparation, formation mechanism and mechanical properties of multilayered TiO_2-organic nanocomposite film 被引量:2
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作者 牟文宁 翟玉春 石双志 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2015年第4期1128-1134,共7页
Ti O2-organic multilayered nanocomposite films were deposited on a self-assembled monolayer-coated silicon substrate based on layer-by-layer technique and chemical bath deposition method by a hydrolysis of Ti Cl4 in a... Ti O2-organic multilayered nanocomposite films were deposited on a self-assembled monolayer-coated silicon substrate based on layer-by-layer technique and chemical bath deposition method by a hydrolysis of Ti Cl4 in an acid aqueous solution. The chemical compositions, surface morphologies and mechanical properties of the films were investigated by X-ray photoelectron spectrometer(XPS), scanning electron microscopy(SEM) and nanoindentation depth-sensing technique, respectively. The results indicate that the major chemical compositions of the films are Ti and O. The principal mechanism for the nucleation and growth of the films is homogeneous nucleation, and the layer number of films has great influence on the surface morphology and roughness of the films. In addition, mechanical nanoindentation testing presents a significant increase in hardness and fracture toughness of titanium dioxide multilayered films compared with single-layer titanium dioxide thin film. 展开更多
关键词 titanium dioxide multilayered film self-assembly monolayer formation mechanism mechanical properties
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Fiber Coupling of Laser Diode Bar to M ultimode Fiber Array 被引量:10
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作者 王晓薇 肖建伟 +6 位作者 马骁宇 王仲明 方高瞻 冯小明 刘媛媛 刘斌 张敬明 《Journal of Semiconductors》 EI CAS CSCD 北大核心 2002年第5期464-467,共4页
A piece of multimode optical fiber with a low num er ical aperture (NA) is used as an inexpensive microlens to collimate the output r adiation of a laser diode bar in the high numerical aperture (NA) direction.The em... A piece of multimode optical fiber with a low num er ical aperture (NA) is used as an inexpensive microlens to collimate the output r adiation of a laser diode bar in the high numerical aperture (NA) direction.The emissions of the laser diode bar are coupled into multimode fiber array.The radi ation from individual ones of emitter regions is optically coupled into individu al ones of fiber array.Total coupling efficiency and fiber output power are 75% and 15W,respectively. 展开更多
关键词 fiber coupling laser diode bar multimode fiber array fast axis
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Interpolation of near offset using surface-related multiples 被引量:1
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作者 郭书娟 李振春 +2 位作者 仝兆岐 马方正 刘建辉 《Applied Geophysics》 SCIE CSCD 2011年第3期225-232,241,共9页
In this research, we present a seismic trace interpolation method which uses seismic data with surface-related multiples. It is different from conventional seismic data interpolation using information transformation o... In this research, we present a seismic trace interpolation method which uses seismic data with surface-related multiples. It is different from conventional seismic data interpolation using information transformation or extrapolation of adjacent channels for reconstruction of missing seismic data. In this method there are two steps, first, we construct pseudo-primaries by cross-correlation of surface multiple data to extract the missing near- offset information in multiples, which are not displayed in the acquired seismic record. Second, we correct the pseudo-primaries by applying a Least-squares Matching Filter (LMF) and RMS amplitude correction method in time and space sliding windows. Then the corrected pseudo-primaries can be used to fill the data gaps. The method is easy to implement, without the need to separate multiples and primaries. It extracts the seismic information contained by multiples for filling missing traces. The method is suitable for seismic data with surfacerelated multiples. 展开更多
关键词 Surface-related multiples Least-squares Matching Filter RMS amplitude correction seismic interpolation
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Closed BER expression of multi-user DS UWB systemsin indoor fading channel 被引量:3
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作者 樊祥宁 黄勇富 毕光国 《Journal of Southeast University(English Edition)》 EI CAS 2006年第1期16-20,共5页
The bit error rate (BER) performance of multi-user direct spreading bi-phase shift keying (DSBPSK) direct impulse ultra wideband (UWB) systems is analyzed and simulated based on a statistical indoor multi-path f... The bit error rate (BER) performance of multi-user direct spreading bi-phase shift keying (DSBPSK) direct impulse ultra wideband (UWB) systems is analyzed and simulated based on a statistical indoor multi-path fading channel model. The BER of the system is theoretically derived and given in closed form, which is expressed in terms of channel parameters and system parameters such as pulse width parameter, pulse repeat period, user number and pulse waveform. With this BER expression, the effect of these parameters on the system performance can be evaluated in a uniform way. Simulation results well match the theory numerical results, and prove that the multi-access interference (MAI) of DS-BPSK UWB is a normal distribution. 展开更多
关键词 ultra wideband (UWB) direct spreading (DS) bi-phase shift keying (BPSK) MULTI-USER fading channel performance analysis
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Fragmentation Patterns of Diquaternary Dipiperaziniums Containing Dithiocarboxy lGroups by Electrospray Ionization Tandem Mass Spectrometry
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作者 王欣 葛泽梅 +1 位作者 程铁明 李润涛 《Journal of Chinese Pharmaceutical Sciences》 CAS 2004年第1期24-27,共4页
Aim To analyze the fragmentation patterns of diquaternary dipiperaziniumscontaining dithiocarboxyl groups. Methods Positive ion electrospray ionization mass spectrometry inconjunction with tandem mass spectrometry (ES... Aim To analyze the fragmentation patterns of diquaternary dipiperaziniumscontaining dithiocarboxyl groups. Methods Positive ion electrospray ionization mass spectrometry inconjunction with tandem mass spectrometry (ESI-MS^n) was used. Results The fragment ion [M^(2+) Cl^-]^+ showed characteristic double peaks with high intensity instead of the parent molecular ionbeing detected. And [M^(2+) - CH_3^+ ]^+ ion had relatively low intensity. Meanwhile, [M^(2+) Cl^- -Cl^- - PhCH_2^+ ]^+ species had the highest intensity as the base peak, which was originated from[M^(2+) Cl^- ]^+, The detailed fragmentation mechanisms are supported with the tandem massspectrometry. 展开更多
关键词 diquaternary dipiperazinium dithiocarboxyl group ESI-MS^n fragmentationpathway
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An Effective Multiple Model Least Squares Method in Tracking of a Maneuvering Target 被引量:3
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作者 杨位钦 贾朝晖 《Journal of Beijing Institute of Technology》 EI CAS 1995年第1期35+29-34,共7页
A polynomial model, time origin shifting model(TOSM, is used to describe the trajectory of a moving target .Based on TOSM, a recursive laeast squares(RLS) algorithm with varied forgetting factor is derived for tracki... A polynomial model, time origin shifting model(TOSM, is used to describe the trajectory of a moving target .Based on TOSM, a recursive laeast squares(RLS) algorithm with varied forgetting factor is derived for tracking of a non-maneuvering target. In order to apply this algorithm to maneuvering targets tracking ,a tracking signal is performed on-line to determine what kind of TOSm will be in effect to track a target with different dynamics. An effective multiple model least squares filtering and forecasting method dadpted to real tracking of a maneuvering target is formulated. The algorithm is computationally more effcient than Kalman filter and the percentage improvement from simulations show both of them are considerably alike to some extent. 展开更多
关键词 Kalman filters tracking/recursive least squares maneuvering target polynomial model forgetting factor
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Photocatalytic Degradation of Phenol over MWCNTs-TiO2 Composite Catalysts with Different Diameters
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作者 李晨 汪文栋 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 2009年第4期423-428,448,共7页
Titania-based composite catalysts were prepared through a sol-gel route employing multi-walled carbon nanotubes with different diameters. The materials were characterized using thermogravimetric analysis, nitrogen ads... Titania-based composite catalysts were prepared through a sol-gel route employing multi-walled carbon nanotubes with different diameters. The materials were characterized using thermogravimetric analysis, nitrogen adsorption-desorption isotherm, powder X-ray diffraction, scanning electron microscopy, and diffuse reflectance UV-Vis absorption spectra. The application of the catalysts to photocatalytic degradation of phenol was tested under UV-Vis irradiation. A synergetic effect on phenol removal was observed in case of composite catalysts, which was evaluated in terms of apparent rate constant, total organic carbon removal and photonic efficiency. 展开更多
关键词 Photocatalytic degradation PHENOL Titanium dioxide Multi-walled carbon nanotube Composite catalyst
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CALCULATION OF TWO-DIMENSIONAL PARABOLIC STABILITY EQUATIONS 被引量:1
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作者 王伟志 唐登斌 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 2000年第1期36-41,共6页
Two dimensional parabolic stability equations (PSE) are numerically solved using expansions in orthogonal functions in the normal direction.The Chebyshev polynomials approximation,which is a very useful form of ortho... Two dimensional parabolic stability equations (PSE) are numerically solved using expansions in orthogonal functions in the normal direction.The Chebyshev polynomials approximation,which is a very useful form of orthogonal expansions, is applied to solving parabolic stability equations. It is shown that results of great accuracy are effectively obtained.The availability of using Chebyshev approximations in parabolic stability equations is confirmed. 展开更多
关键词 parabolic stability equations Chebyshev approximations two dimensional equation
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Fabrication and characterization of tungsten-containing mesoporous silica for heterogeneous oxidative desulfurization 被引量:7
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作者 张铭 朱文帅 +5 位作者 李宏平 荀苏杭 李猛 李亚男 魏延臣 李华明 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 北大核心 2016年第6期971-978,共8页
A series of functional,tungsten-containing mesoporous silica materials(W-SiO2) have been fabricated directly from an ionic liquid that contained imidazole and polyoxometalate,which acted as mesoporous template and m... A series of functional,tungsten-containing mesoporous silica materials(W-SiO2) have been fabricated directly from an ionic liquid that contained imidazole and polyoxometalate,which acted as mesoporous template and metal source respectively.These materials were then characterized through X-ray diffraction(XRD),transmission electron microscopy(TEM),Raman spectroscopy,Fourier transform infrared spectra(FTIR),diffuse reflectance spectra(DRS),and N2 adsorption-desorption,which were found to contain tungsten species that were effectively dispersed throughout the structure.The as-prepared materials W-SiO2 were also found to possess a mesoporous structure.The pore diameters of the respective sample W-SiO2-20 determined from the TEM images ranged from 2 to 4 nm,which was close to the average pore size determined from the nitrogen desorption isotherm(2.9 nm).The materials were evaluated as catalysts for the heterogeneous oxidative desulfurization of dibenzothiophene(DBT),which is able to achieve deep desulfurization within 40 min under the optimal conditions(Catalyst(W-SiO2-20)= 0.01 g,temperature = 60℃,oxidant(H2O2)= 20 μL).For the removal of different organic sulfur compounds within oil,the ability of the catalyst(W-SiO2-20) under the same conditions to remove sulfur compounds decreased in the order:4,6-dimethyldibenzothiophene Dibenzothiophene Benzothiophene 1-dodecanethiol.Additionally,they did not require organic solvents as an extractant in the heterogeneous oxidative desulfurization process.After seven separate catalytic cycles,the desulfurization efficiency was still as high as 90.3%.From the gas chromatography-mass spectrometer analysis,DBT was entirely oxidized to its corresponding sulfone DBTO2 after reaction.A mechanism for the heterogeneous desulfurization reaction was proposed. 展开更多
关键词 Heterogeneous oxidative desulfurization Tungsten species Mesoporous silica One-pot synthesis ORGANOSULFUR
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Location and Analysis of Introgressed Segments in the Parthenogenetic Progenies of Zea mays×Z. diploperennis by GISH
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作者 魏文辉 覃瑞 +3 位作者 宋运淳 宁顺斌 郭乐群 谷明光 《Acta Botanica Sinica》 CSCD 2002年第3期373-376,共4页
用来自玉米 (ZeamaysL .)与二倍体多年生类玉米 (Z .diploperennisIltis,DoebleyandGuzm偄n)杂交的孤雌生殖后代同一抗病个体的 4个株系进行了基因组原位杂交 ,用改进的杂交技术获得了近 10 0 %的检出率 ,每一检出片段在同源染色体两... 用来自玉米 (ZeamaysL .)与二倍体多年生类玉米 (Z .diploperennisIltis,DoebleyandGuzm偄n)杂交的孤雌生殖后代同一抗病个体的 4个株系进行了基因组原位杂交 ,用改进的杂交技术获得了近 10 0 %的检出率 ,每一检出片段在同源染色体两成员和每两个姊妹染色单体上均有清晰的信号。 展开更多
关键词 maize Zea diploperennis introgressed segments genomic in situ hybridization
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The Influence of Rapid Thermal Annealing on SiGe/Si Multiple-Quantum Wells p_-i_-n Photodiodes
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作者 李成 杨沁清 +3 位作者 王红杰 王玉田 余金中 王启明 《Journal of Semiconductors》 EI CAS CSCD 北大核心 2001年第6期695-699,共5页
The influence of thermal treatment on Si 1-x Ge x/Si multiple-quantum wells (MQW) p-i-n photodiodes has been investigated by photocurrent spectroscopy combined with X-ray double crystal dif... The influence of thermal treatment on Si 1-x Ge x/Si multiple-quantum wells (MQW) p-i-n photodiodes has been investigated by photocurrent spectroscopy combined with X-ray double crystal diffraction.The cutoff wavelength is significantly reduced due to the Si-Ge interdiffusion and partial relaxation of the strained SiGe alloy.The values of the blue shift increase slowly with the annealing temperatures in the range of 750℃ to 850℃.However,the nonlinear changes in photocurrent intensities of the samples annealed at different temperatures have been observed,which is mainly dominated by the generation of misfit dislocations and the reduction of the point defects in the heating process. 展开更多
关键词 SiGe/Si MQW photodiodes blue shift thermal annealing INTERDIFFUSION
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Synthesis and reversal effect of a novel N-substituted phthalimidesugar on doxorubicin resistant of human breast cancer cells
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作者 易文渊 李敏 +5 位作者 杨亚平 吕卓远 徐波 韩冬 李中军 崔景荣 《Journal of Chinese Pharmaceutical Sciences》 CAS 2008年第4期319-323,共5页
Thalidomide (α-N-phthalimido-glutarimide, TLD) is a kind of anti-angiogenic and anti-inflammatory drug, and showed effects in the treatment of several disease entities. In this study, the biological effects of a no... Thalidomide (α-N-phthalimido-glutarimide, TLD) is a kind of anti-angiogenic and anti-inflammatory drug, and showed effects in the treatment of several disease entities. In this study, the biological effects of a novel N-sugar substituted phthalimide (STA-35) on the regulation of multidrug resistance (MDR) to doxorubicin (ADR) were investigated. The proliferation of cancer cells was detected by a SRB assay. The activity of P-glycoprotein (P-gp) was determined by a Flow cytometry. The expression of P-gp was measured by western blotting. The results showed that STA-35 inhibited the proliferation of human breast cancer cell line MCF-7 and its ADR resistant cell line MCF-7/ADR, and the relative resistance was only 1.19. Meanwhile, STA-35 could sensitize the cytotoxicity of ADR in MCF-7/ADR cells. In addition, we found that STA-35 reduced the activity of P-gp by suppressing the P-gp expression, which was indicated by the increase in the accumulation of rhodamine 123 in MCF-7/ADR cells. These results suggested a promising application of STA-35 as the MDR reversing agent. The underlying mechanism of the effects might be attributed to the inhibition of P-gp. 展开更多
关键词 Multidrug resistance THALIDOMIDE PHTHALIMIDE P-GLYCOPROTEIN
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