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Biological control experiment of excess propagation of Cyclops for drinking water security

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Journal of Environmental Sciences 2007年第3期19卷 290-294页

作者： LIN Yao CUI Fu-yi liu dong-mei College of Environmental Science and Engineering Hohai University Nanjing 210098 China School of Municipal and Environmental Engineering Harbin Institute of Technology Harbin 150090 China

Cyclops of zooplankton propagated excessively in eutrophic water body and could not be effectively inactivated by the conventional disinfections process like chlorination due to its stronger resistance to oxidation. In this study, an ecological project was put forward for the excess propagation control of Cyclops by stocking the filter-feeding fishes such as silver carp and bighead carp under the condition of no extraneous nutrient feeding. The results of experiments with different stocking biomass showed that the propagation of Cyclops could be controlled effectively, and the water quality was improved simultaneously by impacting on nutriment level and plankton community structure at proper stocking density of 30 g/m^3 of water. The growth of Cyclops may not be effectually controlled with lower biomass of fish （10 g）, and the natural food chain relation may be destroyed for Cyclops dying out in water while the intense stocking of 120 g per cubic meter of water. In addition, the high predator pressure may accelerate supplemental rate of nutrients from bottom sediments to water body to add the content of total nitrogen and phosphorus in water.

关键词： filter-feeding fishes Cyclops zooplankton biomanipulation water treatment

New Tripartite Nonlinear Entangled State Representation in Quantum Mechanics

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Communications in Theoretical Physics 2008年第10期50卷 867-872页

作者： KUANG Mai-Hua MA Shan-Jun liu dong-mei College of Physics ＆ Communication Electronics Jiangxi Normal University Nanchang 330022 China

Based on the technique of integral within an ordered product of nonlinear bosonic operators,we constructa new kind of tripartite nonlinear entangled state |α,γ〉_λ in 3-mode Fock space,which can make up a complete ... 详细信息

关键词： nonlinear 3-mode entangled state

Extracting Energy Magnetically from Plunging Region of Black-Hole Accretion Disk

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Communications in Theoretical Physics 2007年第2期47卷 374-378页

作者： liu dong-mei YE Yong-Chun WANG Ding-Xiong Department of Physics Huazhong University of Science and Technology Wuhan 430074 China

An analytical expression for the jet power extracted from the plunging region between a black hole （BH） horizon and the inner edge of the disk （hereafter the PL power） is derived based on an improved equivalent circuit in BH magnetosphere with a mapping relation between the radial coordinate of the plunging region and that of the remote astrophysical load. It is shown that the PL power is of great importance in explaining jet power and dominates over the BZ and DL powers for a wide value range of the BH spin. In addition, we show that the PL power derived in our model can be fitted with the strong jet powers of several 3CR FR I radio galaxies, which cannot be explained by virtue of the BZ mechanism. Furthermore, the condition for negative energy of the accreting particles in the plunging region is discussed with the validity of the second law of BH thermodynamics.

关键词： black hole accretion disk jet power radio galaxies

Syntheses and Crystal Structures of Calix[4]arene Dithiocarbazate Schiff Bases

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Chemical Research in Chinese Universities 2010年第4期26卷 572-577页

作者： SUN Jing liu dong-mei WANG Jin-xiang YAN Chao-guo College of Chemistry and Chemical Engineering Yangzhou University Yangzhou 225002 P. R. China

The regioselective syntheses of novel p-tert-butylcalix[4]arenes with functional aldehyde and dithiocarbazate Schiff base groups were carried out. p-tert-Butylcalix[4]arene was alkylated with o-, p-（ω-chloroalkoxy）- benzaldehydes in the system of K2CO3/KI/CH3CN to give calixarene 1,3-dialdehydes. Then the condensation reactions of active calixarene aldehydes with S-methyl and S-benzyldithiocarbazate, calixarene sulfur-containing Schiff bases were efficiently obtained in satisfied yields. The single crystal analysis of the four representative products shows that calixarene aldehydes and Schiff bases exist in cone conformation and there are interesting intermolecular hydrogen-bands and π...π interaction in the crystals.

关键词： Calixarene Alkvlation S-Alkvldithiocarbazate Schiff base: Crystal structure

Microwave Assisted Synthesis of 3,3',3″,3'″-o-,p-Phenylenedi-methylidinetetrakis-(4-hydroxy-2H-1-benzopyran-2-one)

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Chemical Research in Chinese Universities 2010年第6期26卷 933-936页

作者： AN Lin liu dong-mei WANG Jin-xiang YAN Chao-guo College of Pharmacy Xuzhou Medical College Xuzhou 221004 P. R. China College of Chemistry ＆ Chemical Engineering Yangzhou University Yangzhou 225002 P. R. China

Under microwave irradiation,2,2＇-alkoxy-bridging or 4,4＇-alkoxy-bridging dibenzaldehydes reacted with 4-hydroxycoumarin in DMF to give a series of 3,3＇,3″,3＇″-o-and 3,3＇,3″,3＇″-p-phenylenedimethylidinetetrakis-（4-hydroxy-2H-1-benzopyran-2-ones） in moderate *** structures of the synthetic coumarin derivatives were characterized with IR,1H NMR and MS spectroscopy as well as X-ray single crystallography.

关键词： Microwave irradiation One-pot reaction Coumarin Benzopyran-2-one

Removal of cyclops in pre-oxidizing cooperation water treatment process

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2007年第11期8卷 1826-1830页

作者： liu dong-mei CUI Fu-yi WU Ya-qin LIN Tao ZHANG Min YU Ming-xue School of Municipal and Environmental Engineering Harbin Institute of Technology Harbin 150090 China State Key Laboratory of Urban Water Resource and Environment Harbin 150090 China College of Environmental Science and Engineering Hohai University Nanjing 210098 China

Zooplankton cyclops propagates profusely in waterbody, cannot be effectively inactivated by conventional disinfection process, and becomes a troublesome drinking water treatment problem. In this work, the qualitative and quantitative experimental studies were carried out on inactivation of zooplankton cyclops using oxidants, such as chlorine （Cl2）, chlorine dioxide （ClO2）, ozone （O3）, hydrogen peroxide （H2O2）, ozone/hydrogen peroxide （O3/H2O2）, chloramines （Cl2-NH3） and potassium permanganate （KM4nO4）. The influences of various factors include different oxidant dosages, organic substance contents and pH values. The results showed that currently available oxidants used all might inactivate cyclops in some extent. According to the experimental results, chlorine dioxide, ozone, ozone/hydrogen peroxide and chloramines can be selected as effective oxidants for inactivating cyclops because of their strong inactivation abilities. Then the synergic removal effects on cyclops with ozone, ozone/hydrogen peroxide pre-oxidation followed by conventional water treatment processes were investigated, The results showed that ozone and ozone/hydrogen peroxide pre-oxidation can inactivate cyclops effectively, which then can be removed thoroughly by conventional water treatment processes. Cyclops cannot appear in water after filtration with 1.65 mg/L of ozone and 6 mg/L of hydrogen peroxide, with the inactivation rate being 62% before conventional water treatment processes. Cyclops cannot appear in water after filtration with 1.8 mg/L of ozone, with the inactivation rate being 50% before conventional water treatment processes. For different oxidants, when removal rate was the best, the inactivation rate was not the same. These results may provide reference and model for actual waterworks.

关键词： Cyclops of zooplankton Water treatment Inactivation 03 O3/H2O2 pre-oxidation

VARIABLE NON-UNIFORM QUANTIZED BELIEF PROPAGATION ALGORITHM FOR LDPC DECODING

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Journal of Electronics(China) 2008年第4期25卷 539-543页

作者： liu Binbin Bai dong mei Shunliang Department of Electronic Engineering Tsinghua University Beijing 100084 China Department of Electronics Peking University Beijing 100871 China

Non-uniform quantization for messages in Low-Density Parity-Check(LDPC)decoding canreduce implementation complexity and mitigate performance *** the distribution of messagesvaries in the iterative *** letter proposes a variable non-uniform quantized Belief Propaga-tion(BP)*** BP decoding is analyzed by density evolution with Gaussian *** the probability density of messages can be well approximated by Gaussian distribution,by theunbiased estimation of variance,the distribution of messages can be tracked during the *** non-uniform quantization scheme can be optimized to minimize the *** resultsshow that the variable non-uniform quantization scheme can achieve better error rate performance andfaster decoding convergence than the conventional non-uniform quantization and uniform quantizationschemes.

关键词： Low-Density Parity-Check (LDPC) codes Iterative decoding Belief Propagation (BP) Non-uniform quantization

Fetal Hemodynamics and Fetal Growth Indices by Ultrasound in Late Pregnancy and Birth Weight in Gestational Diabetes Mellitus

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Chinese Medical Journal 2016年第17期129卷 2109-2114页

作者： Fang liu Yong liu Ya-Ping Lai Xiao-Ning Gu dong-mei liu Min Yang Department of Ultrasound Beijing Shijitan Hospital Affiliated to Capital Medical University Beijing 100038 China Department of Obstetrics and GynecologY Beijing Shijitan Hospital Affiliated to Capital Medical Llniversity Beijing 100038 China

Background： The offspring of women with gestational diabetes mellitus （GDM） are prone to macrosomia. However, birth weight is difficult to be correctly estimated by ultrasound because of fetal asymmetric growth characteristics. This study aimed to investigate the correlations between fetal hemodynamics, fetal growth indices in late pregnancy, and birth weight in GDM. Methods： A total of 147 women with GDM and 124 normal controls （NC） were enrolled in this study. Fetal hemodynamic indices, including the systolic/diastolic ratio （S/D）, resistance index （RI）, pulsatility index （PI） of umbilical artery （UA）, middle cerebral artery （MCA）, and renal artery （RA）, were collected. Fetal growth indices, including biparietal diameter （BPD）, head circumference （HC）, abdominal circumference （AC）, and femur length, were also measured by ultrasound. Birth weight, newborn gender, and maternal clinical data were collected. Results： The independent samples t-test showed that BPD, HC, and AC were larger in GDM than in NC （P 〈 0.05）. Fetal hemodynamic indices of the UA and MCA were lower （P 〈 0.05）, but those of the RA were higher （P 〈 0.001 ） in GDM than in NC. Birth weight was higher in GDM than in NC （P 〈 0.001）. Pearson＇s correlation analysis showed that hemodynamic indices of the UA were negatively correlated with birth weight, BPD, HC, and AC in both groups （P 〈 0.05）. MCA （S/D, PI, and RI） was negatively correlated with birth weight, HC, and AC in GDM （i- = -0.164, -0.206, -0.200, -0.226, -0.189, -0.179, -0.196, -0.177, and - 0.172, respectively, P 〈 0.05）, but there were no correlations in NC （P 〉 0.05）. RA （S/D, PI, and RI） was positively correlated with birth weight in GDM （r = 0.168, 0.207, and 0.184, respectively, P 〈 0.05）, but there were no correlations in NC （P 〉 0.05）. Conclusion： Fetal hemodynamic indices in late pregnancy might be helpful for estimating newborn birth weight in women with GDM.

关键词： Fetus Gestational Diabetes Mellitus Infant Middle Cerebral Artery Renal Artery Ultrasound Umbilical Artery

含单负特异材料一维无序扰动周期结构中的光子局域特性研究

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物理学报 2010年第10期59卷 7066-7072页

作者：刘冬梅韩鹏华南师范大学量子信息技术重点实验室广州510006

采用传输矩阵法研究了电磁波在由单负特异材料组成的一维无序扰动周期结构中的Anderson局域(Anderson Localization)行为,分别讨论了色散和非色散两种模型.结果发现,在对应周期结构的通带位置,无序的引入对局域长度的影响较大,而在带隙... 详细信息

采用传输矩阵法研究了电磁波在由单负特异材料组成的一维无序扰动周期结构中的Anderson局域(Anderson Localization)行为,分别讨论了色散和非色散两种模型.结果发现,在对应周期结构的通带位置,无序的引入对局域长度的影响较大,而在带隙位置,影响较小,几乎可以忽略.该性质与我们曾讨论的随机结构有较明显不同.导致这种局域性质的主要原因应为,光在单负材料组成的系统中的传输主要依赖于两种单负材料间的界面.在无序扰动结构中,该界面数相对于周期结构并没有减少,因此对光的传输性质影响较小;而随机结构中,界面数显著减少,导致该结构中光被强烈局域,表现出相对较小的局域长度.在色散模型中,研究发现无序对于带隙中心的光的传输性质没有影响.特殊的,当两层的有效光程厚度比为1时,该处是一退局域点.这些结果有利于了解由特异材料组成的结构系统中光的传输机理。

关键词：单负特异材料局域长度传输矩阵法退局域