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Cytological analysis and genetic control of rice anther development

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Journal of Genetics and Genomics 2011年第9期38卷 379-390页

作者： Dabing Zhang Xue luo lu zhu Institute of Plant Science State Key Laboratory of Hybrid Rice School of Life Sciences and Biotechnology Shanghai Jiao Tong University Shanghai 200240 China Bio-X Research Center Shanghai Jiao Tong University Shanghai 200240 China

Microsporogenesis and male gametogenesis are essential for the alternating life cycle of flowering plants between diploid sporophyte and haploid gametophyte generations. Rice （Oryza sativa） is the world＇s major staple food, and manipulation of pollen fertility is particularly important for the demands to increase rice grain yield. Towards a better understanding of the mechanisms controlling rice male reproductive development, we describe here the cytological changes of anther development through 14 stages, including cell division, differentiation and degeneration of somatic tissues consisting of four concentric cell layers surrounding and supporting reproductive cells as they form mature pollen grains through meiosis and mitosis. Furthermore, we compare the morphological difference of anthers and pollen grains in both monocot rice and eudicot Arabidopsis thaliana. Additionally, we describe the key genes identified to date critical for rice anther development and pollen formation.

关键词： Rice (Oryza Sativa) Anther Developmental stages Cellular morphology Arabidopsis thaliana

Aggregation Behaviors of Tricarbocyanine Dye in Water and in AOT Reverse Micelles

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Chinese Journal of Chemistry 2011年第3期29卷 405-410页

作者： zhu, Ruixue lu, Rong Yu, Anchi Department of Chemistry Renmin University of China Beijing 100872 China

The photophysical property of the tricarbocyanine dye IR144 has been extensively studied in non-aqueous solvents. However, as a potential near-infrared biomedical imaging probe, the photophysical property of IR144 in water is still little known. So, the aggregation behaviors of IR144 in water with steady-state absorption spectroscopy and integrated polarization dependent femtosecond pump-probe spectroscopy were investigated. Through comparing the absorption spectral bandshape of IR144 in water and in water pool of AOT reverse micelles, It is found that IR144 form dimer aggregates in water even at very low concentration （〈 1.0× 10^- 7 moloL 1）. And the absorption spectrum of the IR144 aggregates always displays a bimodal feature, which is independent of the dye concentration ranging from 1.0 × 10^-7 to 1.0 × 10^-4 mol·L^-1. For better understanding the aggregation behaviors of IR144 in water, we measured the ground state recovery kinetics and the reorientation kinetics of IR144 in water and in water pool of AOT reverse micelles （W0= [H2O]/[AOT], W0=40）. It is found that the fluorescence quantum yield of 1R144 in water is lower than that in water pool of AOT reverse micelles, and the reorientation time of IR144 in water is slower than that in water pool of AOT reverse micelles. Those kinetic measurements also verify that IR144 exists as dimer aggregates in water.

关键词： photophysics photochemistry kinetics IR 144 aggregates AOT reverse micelles

Experimental research on charging characteristics of a solar photovoltaic system by the pressure-control method

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2011年第6期12卷 470-474页

作者： Hua zhu Zhang-lu XU Zi-juan CAO Institute of Thermal Science and Power Systems Zhejiang University Hangzhou 310027 China

The charging characteristics of the valve-regulated lead acid(VRLA) battery driven by solar energy were experimentally studied through the pressure-control method in this *** aims of the research were to increase charging efficiency to make the most of solar energy and to improve charging quality to prolong life of *** charging process of a 12 V 12 A·h VRLA battery has been tested under the mode of a stand-alone photovoltaic(PV) *** show that the pressure-control method can effectively control PV charging of the VRLA battery and make the best of PV cells through the maximum power point tracking(MPPT).The damage of VRLA battery by excess oxygen accumulation can be avoided through the inner pressure control of VRLA *** such as solar radiation intensity,charging power,inner pressure of the battery,and charging current and voltage during the charging process were measured and analyzed.

关键词： Solar photovoltaic(PV) system Charging characteristics Pressure-control method

Provably secure robust threshold partial blind signature

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Science in China(Series F) 2006年第5期49卷 604-615页

作者： CAO Zhenfu zhu Haojin lu Rongxing Department of Computer Science and Engineering Shanghai Jiao Tong University Shanghai 200030 China

Threshold digital signature and blind signature are playing important roles in cryptography as well as in practical applications such as e-cash and e-voting systems. Over the past few years, many cryptographic researchers have made considerable headway in this field. However, to our knowledge, most of existing threshold blind signature schemes are based on the discrete logarithm problem. In this paper, we propose a new robust threshold partial blind signature scheme based on improved RSA cryptosystem, This scheme is the first threshold partial blind signature scheme based on factoring, and the robustness of threshold partial blind signature is also introduced. Moreover, in practical application, the proposed scheme will be especially suitable for blind signature-based voting systems with multiple administrators and secure electronic cash systems to prevent their abuse.

关键词： threshold signature blind signature improved RSA cryptosystem factoring problem electronic cash.

Climatological distribution of lightning density observed by satellites in China and its circumjacent regions

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Science China Earth Sciences 2005年第2期48卷 219-229页

作者： MA Ming TAO Shanchang zhu Baoyou lu Weitao School of Earth and Space Sciences University of Science and Technology of ChinaHefei230026China School of Earth and Space SciencesUniversity of Science and Technology of ChinaHefei230026China School of Earth and Space SciencesUniversity of Science and Technology of ChinaHefei230026China School of Earth and Space SciencesUniversity of Science and Technology of ChinaHefei230026China

The 0.5°× 0.5° grid resolution distribution of lightning density in China and its circumjacent regions have been analyzed by using the satellite-borne OTD (Apr 1995-Mar 2000) and LIS (Dec 1997-Mar 2003) databases. It is shown that: (i) Firstly, the variability of the lightning density (LD) is particularly pronounced over the different subareas, 9 times greater over the south than the north side of Himalayas Mountains, 2.5 times greater over the eastern than the western area of China. While the maximum and minimum LD are respectively 31.4fl/km2/a (in Guangzhou region) and less than 0.2fl/km2/a (in the desert of western China). Secondly, the LD of China's continent regularly varies with latitude and distance off coast, which is consistent with annual mean precipitation in varying trend. In conclusion, the Qinghai-Tibet Plateau, the China's three-step staircase topography and the latitude are three important factors affecting macro-scale characteristics of the LD distribution, (ii) The regional differences in LD distribution are closely related to the mesoscale orographic forcing. In the eastern humid regions of China, the high LD belts often appear along the mesoscale mountains (with south-north or northeast-southwest direction, 500-1500 m ASL) and hills, while the low LD belts often appear on the plain and basin (valley) between the mountains. But in the western cold and arid regions of China, the relatively high LD belts mostly appear on the Qinghai Lake area of the southern side of Qilian Mountain, Yili River valley, the basin between Tanggula Mountains and Nyainqentanglha. On the coastal land, the high LD centers appear in regions where mountain and hill and large cities are located. This seems to be related to the interaction between the sea-land breeze and mountain-valley wind or city heat island effect, (iii) The China Sea is one of the relatively high LD zones on global oceans. It is very interesting that a high LD belt is located along the Kuroshio area. It i

关键词： OTD/LIS, distribution of lightning density, orographic forcing, coastal land, Kuroshio.

Research on the falling film flow and heat transfer characteristics of FLNG spiral wound heat exchanger under sea conditions

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Petroleum Science 2022年第3期19卷 1276-1290页

作者： Chong-Zheng Sun Liang Liu Yu-Xing Li Jian-lu zhu College of Pipeline and Civil Engineering/Shandong Provincial Key Laboratory of Oil&Gas Storage and Transportation Safety/Qingdao Key Laboratory of Circle Sea Oil&Gas Storage and Transportation Technology China University of PetroleumQingdaoShandong266580China

As the key equipment of floating liquefied natural gas(FLNG)process,the performance of spiral wound heat exchanger(SWHE)influences operation costs and reliability of the whole *** sea conditions destroy the falling film flow state of the refrigeration and then affect the heat transfer performance of FLNG *** order to design and optimize the SWHE,a cryogenic experimental device of FLNG process and a numerical model of falling film flow have been constructed to study the effects of sea conditions on the falling film flow and heat transfer characteristics of *** cryogenic experimental results show that the pitching conditions have larger effects on the heat transfer performance than *** the pitching angle of 7°,the natural gas temperature and gaseous refrigerant temperature increase by 3.22°C and 7.42°C,*** flow rates of refrigerant and feed natural gas have a great impact on the heat transfer performance of SWHE under pitching and compound sloshing *** the tilt angle increases to 9°,the tube structure with outer diameter D=8 mm and pipe spacing S=4 mm is recommended to reduce the drying area of the pipe wall surface.

关键词： FLNG Spiral wound heat exchanger Falling film flow Cryogenic heat transfer Sea condition

Population synthesis of ultra-compact X-ray binaries

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Research in Astronomy and Astrophysics 2012年第11期12卷 1526-1534页

作者： Chun-Hua zhu Guo-Liang lu Zhao-Jun Wang School of Physical Science and Technology Xinjiang University Urumqi 830046 China

Ultra-compact X-ray binaries （UCXBs） are very interesting and impor- tant objects. By taking the population synthesis approach to the evolution of binaries, we carry out a detailed study of UCXBs. We estimate that there are - 5000-10000 UCXBs in the Galaxy, and their birthrates are - 2.6-7.5×10-4 yr-1. Most UCXBs are transient X-ray sources, but their X-ray luminosities are much lower than those of persistent sources. Therefore, the majority of observed UCXBs should be persistent sources. About 40% - 70% of neutron stars （NSs） in UCXBs form via an accretion- induced collapse from an accreting ONe white dwarf （WD）, 1%-10% of NSs in UCXBs form via core-collapse supernovae and others form via the evolution-induced collapse of a naked helium star. About 50% - 80% of UCXBs have naked helium star donors, 5% - 10% of UCXBs have HeWD donors, 15% - 40% of UCXBs have COWD donors and UCXBs with ONeWD indicates that the uncertainty mainly comes which develops in these systems. donors are negligible. Our investigation from evolution of the common-envelope

关键词： binaries: close -- stars: neutron -- X-rays: binaries

An intelligent method for controlling the ECP braking system of a heavy-haul train

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Transportation Safety and Environment 2020年第2期2卷 133-147页

作者： Chun Tian Mengling Wu lu zhu Jun Qian Institute of Rail Transit Tongji University United Automotive Electronic Systems Co. Ltd.

An intelligent control method is proposed for the electronically controlled pneumatic(ECP)braking system of a heavy-haul train. The gradient of the ramp is estimated using a Kalman filter in real time and the braking force is adjusted by the backstepping method, so that vehicles on different gradients change their brake pressure with the change in the gradient to keep the instantaneous deceleration of each vehicle consistent, thus reducing the longitudinal impact between vehicles. The longitudinal impact of heavy-haul trains with and without intelligent control under different gradients, initial braking speeds, loads and complex terrains are simulated and analysed. The results show that when the intelligent control is applied, each vehicle can adjust its brake pressure in time according to the change of gradient. The intelligent control method can effectively alleviate the longitudinal impact of vehicles, and the reduction rate remains greater than 40% under the influence of various factors.

关键词： electronically controlled pneumatic braking system heavy-haul train Kalman filter longitudinal impact

VUV luminescence properties of Y_(0.95)Eu_(0.05)PO_4 phosphor derived by a modified solid-state route

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Rare Metals 2008年第4期27卷 354-357页

作者： ZHENG Cuihong zhu Weichang WANG lu School of Materials Science and Engineering and Anhui Key Laboratory of Metal Materials and Processing Anhui University of Technology Ma ＇anshan 243002 China

A modified solid-state route was attempted to prepare Y0.95 Eu0.05PO4 PDP phosphor, involving milling a powdered mixture of YCl3, EuCl3, and （NH4）2HPO4 and calcining the milling-derived precursor. The thermal decomposition behavior of the milling-derived precursor was investigated by thermogravimetric analysis （TGA）. Phase compositions, morphologies, and luminescence properties of the prepared phosphor powder were characterized by X-ray diffraction （XRD）, scanning electron microscope （SEM）, and vacuum ultraviolet （VUV） emission spectra, respectively. The results indicated that the Y0.95Eu0.05PO4 phosphor powder obtained at a calcination temperature of 900℃ was xenotime-structured. The phosphor powder particles were uniform and spherical-shaped with a primary particle size of-200 um. In comparison with that derived by the conventional solid-state route, the phosphor powder prepared by the modified solid-state route exhibited a higher color purity, presenting a predominant emission peak at 619 nm under 147 um VUV excitation.

关键词： phosphor luminescence properties vacuum ultraviolet solid-state reaction