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非对称光折变全息空间光孤子的存在曲线

物理学报 2004年第9期53卷 3014-3019页

作者：刘劲松华中科技大学激光技术国家重点实验室武汉430074

证明了在加外电场的光折变晶体中存在非对称全息空间光孤子对 ,其特征是孤子对中的两个孤子具有相同的宽度、不同的振幅 .给出了这种孤子对的存在曲线 ,其中存在三个具有不同特征的区域 :对于给定的外加电场来说 ,当孤子对中两个孤子的... 详细信息

证明了在加外电场的光折变晶体中存在非对称全息空间光孤子对 ,其特征是孤子对中的两个孤子具有相同的宽度、不同的振幅 .给出了这种孤子对的存在曲线 ,其中存在三个具有不同特征的区域 :对于给定的外加电场来说 ,当孤子对中两个孤子的入射峰值强度之和与背景光强度之比足够大或者足够小时 ,孤子宽度强烈依赖于这个比值 ,而在此中间的一段区域 ,孤子宽度几乎不随这个比值而变化 .非对称情况下这个中间区域的范围比对称情况的窄 .

关键词：空间光孤子光折变非线性光学全息光栅光折变晶体孤子宽度

Effect of hot isostatic pressing nitrogen on the microstructure and properties of a Ti(C,N)-based cermet

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Rare Metals 2006年第4期25卷 321-325页

作者： YAN Xianmei XIONG Weihao YANG Yong ZHENG Liyun state key {2. of Die and Mould technology Huazhong University of Science and Technology Wuhan 430074 China

The high-temperature, high-pressure hot isostatic pressing technology was used for depositing hard coatings on Ti（C, N）-based cermets. The rnicrostructure and properties of the sample were investigated using optical microscopy, scan- ning electron microscopy, X-ray diffraction, electron probe microanalysis, and microhardness tester. The results showed that the rich titanium and nitrogen in surface zone were induced by the heat treatment. The high nitrogen activity of the surface region was the driving force for outward transport of titanium and inward transport of tungsten in the cobalt binder. The toughness and hardness were improved and a hardness gradient was formed. It is the high-temperature, high-pressure N2.that enables closure of holes, thereby alleviating defects and prolonging tool life.

关键词： Ti(C, N)-based cermet hot isostatic pressing microstructure properties

Arbuscular mycorrhizal for-mation of crucifer leaf mus-tard induced by flavonoids apigenin and daidzein

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Chinese science Bulletin 2004年第12期49卷 1254-1261页

作者： DONG Changjin1,2.& ZHAO Bin1 1. state key {2. of Agricultural Microbiology, huazhong Agri- cultural university, wuhan 430070, china 2. Department of Biology, Hubei Normal university, Huangshi 435002. china 1. state key {2. of Agricultural Microbiology Huazhong Agricultural University 430070 Wuhan China 2. Department of Biology Hubei Normal University 435002 Huangshi China

Flavonoids from legume root secretion may probably act as signal molecules for expression of Rhizobial “nod” nodulation genes and AM fungal symbiotic gene. Leaf mustard is a non-mycorrhizal plant; it does not contain fla- vonoids and other signal molecules. AM fungi could not in- fect the roots of leaf mustard and form a symbiont in nature, when it was treated with flavonoids (apigenin or daidzein). The results of trypan blue staining showed that two kinds of AM fungi (G. intraradices and G. mosseae) successfully in- fected the roots of non-mycorrhizal plant leaf mustard. AM fungi grew towards and colonized the roots of leaf mustard, producing young spores and completing the course of life. AM fungi are the only one kind of fungi with ALP activity. The result of ALP staining has also proved that AM fungi infected successfully the roots of leaf mustard. AM fungi (G. intraradices and G. mosseae) that existed in the roots of non-mycorrhizal plant leaf mustard were probed by nested PCR and special molecular probes. The above-mentioned proof chains have fully proved that flavonoids induced AM fungi (G. intraradices and G. mosseae) to infect non-my- corrhizal plant and establish symbiotic relationship.

关键词：非菌根植物免疫十字花科叶芥菜芹甙元大豆黄酮类黄酮灌木菌根真菌嵌套PCR trypan蓝色染色

A Network-Based VPN Architecture Using Virtual Routing

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wuhan university Journal of Natural {2.s 2005年第1期10卷 161-164页

作者： ZHANG Bao-liang 1,2.HU Han-ping 1,2.,WU Xiao-gang 1,2. KONG Tao 31.state Education Ministry key {2. of Image Information and Intelligent Control, wuhan 430074, Hubei, china 2.Institute of Pattem Recognition and Artificial Intelligonce, huazhong university of science and technology, wuhan 430074, Hubei, china 3.709th Research Institute of china Shipbuilding Engineering Society, wuhan 430074, Hubei, china state Education Ministry key Laboratory of Image Information and Intelligent Control Wuhan China huazhong university of {2. and technology Institute of Pattern Recognition and Artificial Intelligonce Wuhan China (GRID:grid.33199.31) (ISNI:***) state Education Ministry key Laboratory of Image Information and Intelligent Control Wuhan China (GRID:grid.33199.31) huazhong university of {2. and technology Institute of Pattern Recognition and Artificial Intelligonce Wuhan China (GRID:grid.33199.31) (ISNI:***) 709th Research Institute of china Shipbuilding Engineering Society Wuhan China (GRID:grid.33199.31)

A network-based Virtual Private Network (VPN) architecture by using fundamental routing mechanism is proposed. This network is a virtual overlay network based on the relay of IP-in-IP tunneling of virtual routing modules. The packet format employs the encapsulation of IPSec ESP(Encapsulating Security Payload), an impact path code and an extended DS(Differentiated Services) code to support multi-path routing and QoS. Comparing with other models of VPN, this network system can be deployed in the current network with little investment, and it is easy to implement. The simulation result shows its performance is better than the traditional VPN system of black box mode.

关键词： virtual routing network-based VPN proactive defense

Large second-order optical nonlinearities of s-triazine derivatives: View from micro molecules to macro crystals

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science china Chemistry 2005年第3期48卷 203-209页

作者： FANG Qi1, LEI Hong2. CUI Yuezhi3, HUANG Zhenli4, XUE Gang1 & YU Wentao1 1. state key {2. of Crystal Materials, Shandong university, Jinan 2.0100, china 2. School of Information science and Engineering, Shandong university, Jinan 2.0100, china 3. Department of Chemical Engineering, Light Industry College of Shandong, Jinan 2.0100, china 4. key {2. of Biomedical Photonics, Ministry of Education, huazhong university of science and technology,{12., china 1. state key {2. of Crystal Materials Shandong University 250100 Jinan China 2. School of Information science and Engineering Shandong University 250100 Jinan China 3. Department of Chemical Engineering Light Industry College of Shandong 250100 Jinan China 4. key laboratory of Biomedical Photonics Ministry of Education Huazhong University of Science and Technology 430074 Wuhan China

Three s-triazine derivatives have been synthesized and their structures been de-termined. These are Compound I: 2.4-dimethyl-6-(p-N,N-dimethylaminostyryl)-s-triazine (abbre-viated to NMe-1), Compound II: 2.4-dimethyl-6-(p-N,N-diethylaminostyryl)-s-triazine (to NEt-1), and Compound III: 2.methyl-4,6-bis(p-N,N-dimethylaminostyryl)-s-triazine (NMe-2.. NMe-1 and NEt-1 molecules belong to the D-π-A type with a one-dimensional charge-transfer character. NMe-1 crystallizes to centrosymmetric P1 space group, while NEt-1 to non-centrosymmetric polar Cc space group with all of the molecular charge-transfer axes taking the same orientation. Under the irradiation of 1064 nm fundamental laser, NEt-1 powder crystals radiate a 2.order harmonic light with an intensity 46.8 times that of urea. The Λ typed NMe-2.molecule, which has a two-dimensional charge-transfer character, crystallizes to polar P2. space group. Its powder crystals exhibit a 2.order harmonic intensity 46.2.times that of urea. The quantum chemical cal-culations and tensor analyses have been carried out to reveal the dependence of the macro 2.order nonlinear optical (NLO) efficiency on the micro 2.order NLO coefficients (β) and on the crystalline packing styles.

关键词： s-triazine derivatives, synthesis, structure, SHG intensities of crystals, βvalues of molecules.

EXTERNAL BODY FORCEIN FINITE DIFFERENCE LATTICE BOLTZMANN METHOD

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Journal of Hydrodynamics 2005年第4期17卷 473-477页

作者： CHEN Sheng LIU Zhao-hui SHI Bao-chang ZHENG Chu-guang state key {2. of coal combustion Huazhong University of Science and Technology Wuhan 430074 China

A new finite difference lattice Boltzmann scheme is developed. Because of analyzing the influence of external body force roundly, the correct Navier-Stokes equations with the external body force are recovered, without any additional unphysical terms. And some numerical results are presented. The result which close agreement with analytical data shows the good performance of the model.

关键词： Finite Difference Lattice Boltzmann Method (FDLBM) body force

Incompatibility behavior of a symbiotic plasmid pMH7653Rb in Mesorhizobium huakuii 7653R

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science china(Life sciences) 2010年第6期53卷 738-742页

作者： HU GuoYuan1,LI WeiWei1 & ZHOU JunChu2.1key laboratory for Green Chemical Process of Ministry of Education,{2. Institute of technology,{2. 430073,china 2.6} key laboratory of Agricultural Microbiology,huazhong Agricultural university,{2. 430070,china 1. key laboratory for Green Chemical Process of Ministry of Education Wuhan Institute of Technology Wuhan 430073 China2. State Key Laboratory of Agricultural Microbiology Huazhong Agricultural University Wuhan 430070 China

Mesorhizobium huakuii strain 7653R harbored two indigenous plasmids named pMH7653Ra and *** larger plasmid pMH7653Rb (symbiotic plasmid) was transferred to *** HN308SR harboring three plasmids: pMHHN308a,pMHHN308b and pMHHN308c,and HN3015SR harboring three plasmids: pMHHN3015a,pMHHN3015b and pMHHN3015c by tri-parent *** stable indigenous plasmids,pMHHN308b and pMHHN308c of HN308SR,were co-eliminated due to the introduction of pMH7653Rb,and the transconjugant was named *** results implied that pMH7653Rb and pMHHN308b,pMHHN308c were incompatible and might have been ascribed to the same incompatible *** plasmid profiles of transconjugant HN3015SRN14 showed that the second largest plasmid pMHHN3015b of HN3015SR was cured due to the introduction of *** results also implied that pMH7653Rb and pMHHN3015b were *** from plant nodulation tests showed that pMH7653Rb could only maintain the nodulation ability in transconjugant HN308SRN14 and its nodule number was more than that of wild strain HN308SR,but could not replace the nitrogen fixation effect of pMHHN308b and *** plasmid cured mutant HN308SRN14D harboring only pMHHN308a formed null nodules that demonstrated pMHHN308a was relevant to nodulation ***3015SRN14 harboring pMH7653Rb,pMHHN3015a and pMHHN3015c formed null nodules while HN3015SRN14D containing pMHHN3015a and pMHHN3015c lost the nodulation *** plasmid replication repC-like gene sequences were detected by a polymerase chain reaction from 7653R,HN308,HN3015,HN308SRN14 and *** repC gene sequence similarities of the strains tested attained 99%.

关键词： Astragalus sinicus conjugative plasmid transfer indigenous plasmid Mesorhizobium huakuii plasmid curing plasmid incompatibility Tn5-sacB

The Influence of Mold Pressing Parameters on PTC of HDPE/CB Composites

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Journal of wuhan university of {2.(Materials science) 2005年第1期20卷 49-51,59页

作者：易回阳 state key {2. of Mold technology Huazhong University of Science and Te chnologyWuhan 430074China College of Chemistry and Enviorment Engineering Hubei Normal UniversityHuangs hi 435002China

The influence of mold pressing parameters on the positive temperature coefficien t of high-density polyethylene/carbon black composites was investigated. The co mposites with a low resistivity at room temperature and a high positive temperat ure coefficient can be obtainee with the mold pressing parameters as follows: mo ld pressing pressure 6-14MPa, mold pressing temperature 150-170℃, mold pressi ng time about 15min, and room temperature of molded specimen after cooling for 2.0-60 minutes. The positive temperature coefficient effect of the composite is 7 .7 when it is prepared under the mold pressing parameters, and the negative temp erature coefficient effect is less than 0.8. Scanning electron microscopy (SEM) reveals some aggregations of carbon black particles with a size of 1μm inside t he composite, which was obtained at the mold pressing temperature of 180℃.

关键词： composites PTC molding

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一种降低列阵波导光栅相邻信道串扰的方法

中国激光 2004年第3期31卷 313-317页

作者：朱大庆华中科技大学激光技术国家重点实验室湖北武汉430074

阵列波导光栅 (AWG)作为波长滤波器在光通信领域具有很大的应用前景。串扰是影响阵列波导光栅应用的重要因素之一。为了降低阵列波导光栅相邻信道的串扰 ,本文提出并研究了一种降低阵列波导光栅的新方法。该方法利用阵列波导光栅的衍射... 详细信息

阵列波导光栅 (AWG)作为波长滤波器在光通信领域具有很大的应用前景。串扰是影响阵列波导光栅应用的重要因素之一。为了降低阵列波导光栅相邻信道的串扰 ,本文提出并研究了一种降低阵列波导光栅的新方法。该方法利用阵列波导光栅的衍射特点性 ,通过调节阵列波导光栅的自由光谱范围 (FSR)、罗兰圆焦距和阵列波导数目 ,使得各信道信号的输出极小值处于其它信道输出波导中心 ,无次极大处于其它波导中 ,从而降低了阵列波导光栅的串扰 ,特别是相邻信道之间的串扰。通过光束传播方法 (BPM)的模拟了具有不同FSR的 1× 16阵列波导光栅 ,结果显示 ,该方法能将相邻信道之间的串扰降低约 5 .7dB。

关键词：光电子学阵列波导光栅相邻信道串扰集成光学光通信