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Association of aphid life stages using DNA sequences： A case study of tribe Eriosomatini （Hemiptera： Aphididae Pemphiginae）

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Insect Science 2008年第6期15卷 545-551页

作者： He-Cai Zhang Dong Zhang ge-Xia Qiao Institute of Zoology Chinese Academy of Sciences Beijing Henan Normal University Xinxiang Henan Province Graduate University of the Chinese Academy of Sciences Beijing China

Association of aphid life stages based on a portion of COI sequence was applied in Eriosomatini. three aphid specimens, nos. 17496, 19265a, and 19265b collected on Gramineae roots all clustered with tetraneura chinensis Mordvilko with strong support. the average pairwise p-distance among the four taxa was 0.001 （range, 0.000-0.002）, and that among all the ingroup taxa was 0.065 （range, 0.000-0.141）. this indicated that nos. 17496 and 19265 b were the secondary-host morphs of t. chinensis. In this paper the secondary host morph of t. chinensis is described for the first time. With the identification of more species＇ secondary-host morphs, aphids identification based on this morph will be made easily.

关键词： COI sequence Eriosomatini primary host morph secondary host morph tetraneura chinensis

the complete mitochondrial genome of Cervaphis quercus （Insecta： Hemiptera： Aphididae： Greenideinae）

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Insect Science 2014年第3期21卷 278-290页

作者： Yuan Wang Xiao-Lei Huang ge-Xia Qiao Key Laboratory of Zoological Systematics and Evolution Institute of Zoology Chinese Academy of Sciences University of Chinese Academy of Sciences Beijing China

the mitochondrial genome of Cervaphis quercus has been sequenced and annotated. the entire genome of 15 272 bp encodes two ribosomal RNA genes （rrnL and rrnS）, 22 transfer RNA （tRNA） genes, 13 protein-coding genes and a control region. the genome has the same gene order as that found in the inferred ancestral insect. Nucleotide composition is highly A＋t biased. All protein-coding genes use standard mitochondrial initiation codons. Secondary structure models of the two ribosomal RNA genes ofC. quercus are similar to those proposed for other insects. All tRNAs have the classic clover-leaf structure, except for the dihydrouridine （DHU） arm of trnS （AGN）, which forms a simpleloop. the presence of structural elements in the control region is also discussed, with an emphasis on the possible regulation of replication and/or transcription. Comparison withmitochondrial genomes of other aphid species shows their gene arrangements are conserved; however, the variety of repeat regions in species from a different aphid subfamily,Aphidinae, suggests that they resulted from independent evolutionary events.

关键词： aphid control region gene arrangement mitogenome repeat region

Spatial modulation of unitary impurity-induced resonances in superconducting CeCoIn5

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Frontiers of physics 2016年第3期11卷 105-111页

作者： ge Zhang Bin Liu Yi-FengYang Shiping Feng Department of Physics Beijing Jiaotong University Beijing 100044 China Beijing National Laboratory for Co:~densed Matter Physics and Institute of Physics Chinese Academy of Sciences Beijing 100190 China Collaborative Innovation Center of Quantum Matter Beijing 100190 China Department of Physics Beijing Normal University Beijing 100875 China

Motivated by recent experimental progress in high-resolution scanning tunneling microscopy （StM） techniques, we investigate the local quasiparticle density of states around a unitary impurity in the heavy-fermion superconductor CeCoIns. Based on the t-matrix approach we obtain a sharp nearly zero-energy resonance state in the strong impurity potential scattering localized around the impurity and find qualitative differences in the spatial pattern of the tunneling conductance modulated by the nodal structure of the superconducting gap. these unique features may be used as a probe of the superconducting gap symmetry and, in combination with further StM measurements, may help to confirm the dx2-y2 pairing in CeCoIn5 at ambient pressure.

关键词： pairing symmetries effects of disorder tunneling phenomena

A Non-Contact Original-State Online Real-time Monitoring Method for Complex Liquids in Industrial Processes

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Engineering 2018年第3期4卷 392-397页

作者： Ning Duan Linhua Jiang Fuyuan Xu ge Zhang Center for Heavy Metal Cleaner Production Engineering technology Chinese Research Academy of Environmental Sciences Beijing 100012 China

Failures are very common during the online real-time monitoring of large quantities of complex liquids in industrial processes, and can result in excessive resource consumption and pollution. In this study, we introduce a monitoring method capable of non-contact original-state online real-time monitoring for strongly coated, high-salinity, and multi-component liquids. the principle of the method is to establish the relationship among the concentration of the target substance in the liquid （C）, the color space coor- dinates of the target substance at different concentrations （L＊, a＊, b＊）, and the maximum absorption wave- length （λmax）; subsequently, the optimum wavelength λt of the liquid is determined by a high-precision scanning-type monitoring system that is used to detect the instantaneous concentration of the target substance in the flowing liquid. Unlike traditional monitoring methods and existing online monitoring methods, the proposed method does not require any pretreatment of the samples （i.e., filtration, dilution, oxidation/reduction, addition of chromogenic agent, constant volume, etc.）, and it is capable of original- state online real-time monitoring. this method is employed at a large electrolytic manganese plant to monitor the Fe3. concentration in the colloidal process of the plant＇s aging liquid （where the concentra- tions of Fe3＋, Mn2＋, and （NH4）2SO4 are 0.5-18 mg.L 1, 35-39 g.L 1, and 90-110 g.L 1, respectively）. the relative error of this monitoring method compared with an off-line laboratory monitoring is less than 2%.

关键词： Complex liquid Original-state monitoring Online real-time Non-contact identification

Industrialization prospects for hydrogen production by coal gasification in supercritical water and novel thermodynamic cycle power generation system with no pollution emission

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Science China(technological Sciences) 2015年第12期58卷 1989-2002页

作者： GUO LieJin JIN Hui ge ZhiWei LU YouJun CAO ChangQing State Key Laboratory of Multiphase Flow in Power Engineering Xi'an Jiaotong University

Energy conversion and utilization, particularly carbon-based fuel burning in air phase, have caused great environmental pollution and serious problems to society. the reactions in water phase may have the potential to realize clean and efficient energy conversion and utilization. Coal gasification in supercritical water is a typical carbon-based fuel conversion process in water phase, and it takes the advantages of the unique chemical and physical properties of supercritical water to convert organic matter in coal to H2 and CO2. N, S, P, Hg and other elements are deposited as inorganic salts to avoid pollution emission. the State Key Laboratory of Multiphase Flow in Power Engineering has obtained extensive experimental and theoretical results based on coal gasification in supercritical water. Supercritical water fluidized bed reactor was developed for coal gasification and seven kinds of typical feedstock were selected. the hydrogen yield covers from 0.67 to 1.74 Nm3/kg and the carbon gasification efficiency is no less than 97%. this technology has a bright future in industrialization not only in electricity generation but also in hydrogen production and high value-added chemicals. Given the gas yield obtained in laboratory-scale unit, the hydrogen production cost is U.S.$ 0.111 Nm3 when the throughput capacity is 2000 t/d. A novel thermodynamic cycle power generation system based on coal gasification in supercritical water was proposed with the obvious advantages of high coal-electricity conversion efficiency and zero pollutant emission. the cost of U.S.$ 3.69 billion for desulfuration, denitration and dust removal in China in 2013 would have been saved with this technology. Five kinds of heat supply methods are analyzed and the rates of return of investment are roughly estimated. An integrated cooperative innovation center called a new type of high-efficient coal gasification technology and its large-scale utilization was founded to enhance the industrialization o

关键词： industrialization prospects hydrogen production supercritical water gasification power generation zero emission

B effects on crystallization and magnetic properties of Pr_(9.44)Fe_(90.56-x)B_x(x=7.16, 4.76) nanocomposite magnets

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Acta Metallurgica Sinica(English Letters) 2010年第5期23卷 321-326页

作者： Caiyin YOU Na tIAN Zhengxin LU Liling ge Xiaotian JING School of Materials Science and Engineering Xi an University of Technology Xi an 710048 China

Magnetic properties, phase evolution and microstructures of Pr9.44Fe90.56-xBx （x=7.16 and 4.76） nanocomposite magnets have been investigated. Both as-spun ribbons exhibit two-step demagnetization curves, indicating the feature of partial crystallization. By using di？erential scanning calorimeter （DSC） measurements, remained amorphous phase of ribbon with x=7.16 shows a higher crystallization temperature. At optimum annealing temperature of 650℃ for 10 min, better magnetic properties, Mr=1.01 t, jHc=796 kA/m and （BH）max=136 kJ/m3 were obtained in the sample with x=4.76. transmission electron microscopy （tEM） observation confirms that the sample with x=4.76 possesses much finer grain size, which causing a better exchange coupling between soft and hard magnetic grains.

关键词： Nanocomposite magnet Melt spinning Exchange coupling Microstructure

Domain wall network:A dual solution for gravitational waves and Hubble tension?

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Science China(Physics,Mechanics & Astronomy) 2024年第11期67卷 39-46页

作者： Ligong Bian Shuailiang ge Changhong Li Jing Shu Junchao Zong Department of Physics and Chongqing Key Laboratory for Strongly Coupled Physics Chongqing UniversityChongqing 401331China Center for High Energy Physics Peking UniversityBeijing 100871China School of Physics and State Key Laboratory of Nuclear Physics and technology Peking UniversityBeijing 100871China Department of Astronomy Key Laboratory of Astroparticle Physics of Yunnan ProvinceSchool of Physics and AstronomyYunnan UniversityKunming 650091China Beijing Laser Acceleration Innovation Center Beijing 101400China Department of Physics Nanjing UniversityNanjing 210093China CAS Key Laboratory of theoretical Physics Institute of Theoretical PhysicsChinese Academy of SciencesBeijing 100190China

We explore the possibility that domain wall networks generate the stochastic gravitational wave background(SGWB) observed as a strong common power-law process in the Data Release-2 of Parkes Pulsar timing Array. We find that a broad range of parameters, specifically wall tension around σ_(DW)^(29-414 teV)^(3) and wall-decay temperature within t_(d) ~ 20-257 MeV, can explain this phenomenon at a 68% credible level. Meanwhile, the same parameters could ease the Hubble tension if particles from these domain wall networks decay into dark radiation. We establish a direct analytical relationship, ΩGW(f_(p), t_(0))h^(2)~ Ω_(rad)h^(2)(Ω_νΩN_(eff))^(2),to illustrate this coincidence, underlining its importance in the underlying physics and potential applicability to a wider range of models and data. Conversely, if the common power-law process is not attributed to domain wall networks, our findings impose tight limits on the wall tension and decay temperature.

关键词： domain wall gravitational waves Hubble tension

Effects of genistein and equol on human and rat testicular 3β-hydroxysteroid dehydrogenase and 17β-hydroxysteroid dehydrogenase 3 activities

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Asian Journal of Andrology 2010年第4期12卷 519-526页

作者： Guo-Xin Hu Bing-Hai Zhao Yan-Hui Chu Hong-Yu Zhou Benson t. Akingbemi Zhi-Qiang Zheng Ren-Shan ge Population Council New York NY 10065 USA School of Pharmacy Wenzhou Medical College Wenzhou 325000 China Heilongjiang Key Laboratory of Anti-fibrosis Biotherapy Mudanjiang Medical University Mudanjiang 157001 China Departments of Anatomy Physiology and Pharmacology Auburn University Auburn AL 36849 USA the Second Affiliated Hospital Wenzhou Medical College Wenzhou 325000 China

the objective of the present study was to investigate the effects of genistein and equol on 3β-hydroxysteroid de- hydrogenase （3β-HSD） and 17β-hydroxysteroid dehydrogenase 3 （17β-HSD3） in human and rat testis microsomes. these enzymes （3β-HSD and 17β-HSD3）, along with two others （cytochrome P450 side-chain cleavage enzyme and cytochrome P450 17α-hydroxylase/17-20 lyase）, catalyze the reactions that convert the steroid cholesterol into the sex hormone testosterone. genistein inhibited 3β-HSD activity （0.2 μmol L^-1 pregnenolone） with half-maximal inhibition or a half-maximal inhibitory concentration （IC50） of 87 ± 15 （human） and 636 ± 155 nmol L^-1 （rat）. genistein＇s mode of action on 3β-HSD activity was competitive for the substrate pregnenolonrge and noncompetitive for the cofactor NAD＋. there was no difference in genistein＇s potency of 3β-HSD inhibition between intact rat Leydig cells and testis microsomes. In contrast to its potent inhibition of 3β-HSD, genistein had lesser effects on human and rat 17β-HSD3 （0.1 μmol L^-1 androstenedione）, with an IC50 〉 100μmol L^-1. On the other hand, equol only inhibited human 3β-HSD by 42%, and had no effect on 3β-HSD and 17β-HSD3 in rat tissues. these observations imply that the ability of soy isoflavones to regulate androgen biosynthesis in Leydig cells is due in part to action on Leydig cell 3β- HSD activity. Given the increasing intake of soy-based food products and their potential effect on blood androgen levels, these findings are greatly relevant to public health.

关键词： 3β-hydroxysteroid dehydrogenase 17β-hydroxysteroid dehydrogenase 3 enzyme inhibition equol genistein

Controversy about the Origin of the Grain Boundary Internal Friction Peak and Its Clarification

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Journal of Materials Science & technology 1998年第6期14卷 481-490页

作者： t.S.Ke (tingsui ge)(Lab. of Internal Friction and Defects in Solids, Institute of Solid State Physics, Chinese Academy of Sciences,Hefei 230031, China) Lab. of Internal Friction and Defects in Solids Institute of Solid State Physics Chinese Academy of Sciences Hefei 230031 China

In the seventies some scientific workers from France and Italy suggested that the grain boundary internal friction peak (named the K (e) over cap peak in the literature) widely accepted as a grain boundary process, is originated from the motion of lattice dislocations. Since this problem is one of fundamental importance, this controversy has drawn much international attention. Started from 1982, the Hefei research group made a critical analysis of the large amount of literature concerning this problem and,performed a series of crucial experiments to clarify the controversy. It is concluded that the irrelevant evidence suggested by the controverters comes from the farfetched interpretation and the mis-identification of the internal friction peaks appeared under various experimental conditions and different states of the specimens.

关键词： Figure Controversy about the Origin of the Grain Boundary Internal Friction Peak and Its Clarification