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Science China(Physics,Mechanics & Astronomy) 2009年第1期52卷 82-86页

作者： YIN XiangYu song hao ZHOU HuiJun Department of Materials Science and Engineering Nanjing UniversityNanjing 210093China Department of Physics Nanjing UniversityNanjing 210093China

In this study,ultrasound grating was used to measure the sound velocity in solutions of ethylene glycol and polyethylene glycol with molecular weights of 200,600,2000,and *** found Parthasarathy empirical rule,that is,sound velocity is higher in the solution of larger molecules,is invalid in the case of polyethylene glycol solution. We tried to provide a tentative explanation using the Flory-Krigbaum's chained block cloud model.

关键词： ultrasound grating velocity of sound polyethylene glycol

Magnetic moments of hidden-charm strange pentaquark states

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Chinese Physics C 2022年第12期46卷 194-207页

作者： Feng Gao hao-song Li School of Physics Northwest UniversityXi'an 710127China Institute of Modern Physics Northwest UniversityXi'an 710127China Shaanxi Key Laboratory for theoretical Physics Frontiers Xi'an 710127China Peng Huanwu Center for Fundamental Theory Xi'an 710127China

In this study,the magnetic moments of hidden-charm strange pentaquark states with quantum numbers J^(P)=1^(±)/2,3^(±)/2,5^(±)/2,and 7^(+)/2 are calculated in the molecular,diquark-diquark-antiquark,and diquark-triquark *** numerical results demonstrate that the magnetic moments change for different spin-orbit couplings within the same model and when involving different models with the same angular momentum.

关键词： magnetic moment pentaquark molecular model diquark triquark

Study on precipitation and transition mechanisms from the magnetic properties of silicon steel during annealing

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International Journal of Minerals,Metallurgy and Materials 2014年第4期21卷 379-387页

作者： Yong-fei Fan hao Yu Jing Sun Pan Tao Cheng-hao song Xun Zeng School of Materials Science and Engineering University of Science and Technology Beijing

Precipitates play an important role in determining the mechanical and magnetic properties of silicon steel. This paper aims to investigate the growth kinetics of precipitates in commercial silicon steel by analyzing its magnetic properties during isothermal annealing at 200℃. The growth of precipitates was studied by optical microscopy, scanning electron microscopy, transmission electron microscopy, and magnetic measurements. In combination with the coercive field and initial susceptibility, this technique offers the advantage of being non-destructive and providing quantitative information about the number, mean radius of precipitates, and fraction of transformation. An ob- served decrease in the number of precipitated particles indicates that the transformation starts from particles of appreciable initial size.

关键词： silicon steel precipitation growth kinetics magnetic properties isothermal annealing

Determination of minimum flood flow for regeneration of floodplain forest from inundated forest width-stage curve

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Water Science and Engineering 2010年第3期3卷 257-268页

作者： song-hao SHANG Xiao-min MAO State Key Laboratory of Hydroscience and Engineering Department of Hydraulic Engineering Tsinghua University Beijing 100084 P. R. China College of Water Conservancy and Civil Engineering China Agricultural University Beijing 100083 P. R. China

Floods are essential for the regeneration and growth of floodplain forests in arid and semiarid regions. However, river flows, and especially flood flows, have decreased greatly with the increase of water diversion from rivers and/or reservoir regulation, resulting in severe deterioration of floodplain ecosystems. Estimation of the flood stage that will inundate the floodplain forest is necessary for the forest＇s restoration or protection. To balance water use for economic purposes and floodplain forest protection, the inundated forest width method is proposed for estimating the minimum flood stage for floodplain forests from the inundated forest width-stage curve. The minimum flood stage is defined as the breakpoint of the inundated forest width-stage curve, and is determined directly or analytically from the curve. For the analytical approach, the problem under consideration is described by a multi-objective optimization model, which can be solved by the ideal point method. Then, the flood flow at the minimum flood stage （minimum flood flow）, which is useful for flow regulation, can be calculated from the stage-discharge curve. In order to protect the forest in a river floodplain in a semiarid area in Xinjiang subject to reservoir regulation upstream, the proposed method was used to determine the minimum flood stage and flow for the forest. Field survey of hydrology, topography, and forest distribution was carried out at typical cross sections in the floodplain. Based on the survey results, minimum flood flows for six typical cross sections were estimated to be between 306 m3/s and 393 m3/s. Their maximum, 393 m3/s, was considered the minimum flood flow for the study river reach. This provides an appropriate flood flow for the protection of floodplain forest and can be used in the regulation of the upstream reservoir.

关键词： floodplain forest regeneration flow minimum flood stage inundated forest width method ideal point method

Salt-free vesicle-phases and their template effect

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Chinese Science Bulletin 2007年第19期52卷 2593-2599页

作者： SHI XingWang song AiXin hao JingCheng Key Laboratory of Colloid and Interface Chemistry of Ministry of Education Shandong University Jinan 250100 China

Researches on the construction, structure, and formation of vesicles formed from surfactants have attracted great attention from colloid and interface chemists. The vesicles formed from salt-free cationic-anionic surfactant systems are very different from those with excess salts, having many particular properties. In this paper, we introduce the properties of vesicles prepared from salt-free surfactant systems, according to our own results, especially the vesicles formed from surfactants with divalent metal ions as counterions in aqueous solutions and room temperature ionic liquids. Moreover, the primary results on template effect of the metal-ligand vesicles have also been summarized.

关键词：表面活性剂气泡室内温度离子液体模板作用盐液

Encapsulation of selenium sulfide in double-layered hollow carbon spheres as advanced electrode material for lithium storage

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Nano Research 2016年第12期9卷 3725-3734页

作者： Hongwei Zhang Liang Zhou Xiaodan Huang hao song Chengzhong Yu Australian Institute for Bioengineering and Nanotechnology The University of Queensland Brisbane QLD 4072 Australia State Key Laboratory of Advanced Technology for Materials Synthesis and Processing Wuhan University of Technology Wuhan 430070 China

Selenium sulfide/double-layered hollow carbon sphere （SeS2/DLHC） composites have been designed as high-performance cathode materials for novel Li-SeS2 batteries. In the constructed composite, SeS2 is predominantly encapsulated in the interlayer space of DLHCs with a high loading of 75% （weight percentage） and serves as the active component for lithium storage. The presence of Se in the composite and the carbon framework not only alleviate the shuttling of polysulfide, but also improve the conductivity of electrodes. Migration of active materials from the interlayer void to the hollow cavity of DLHCs after cycling, which further mitigates the loss of active materials and the shuttle effect, is observed. As a result, the SeS2/DLHC composite delivers a high specific capacity （930 mA.h.g-1 at 0.2 C） and outstanding rate capability （400 mA.h.g-1 at 6 C）, which is much better than those of SeS2/single-layered hollow carbon sphere, Se/DLHC, and S/DLHC composites. Notably, the SeS2/DLHC composite shows an ultralong cycle life with 89% capacity retention over 900 cycles at 1 C, or only 0.012% capacity decay per cycle. Our study reveals that both SeS2 and the double-layered structures are responsible for the excellent electrochemical performance.

关键词： selenium sulfide double-layered hollowcarbon cathode materials lithium storage

Biosynthesis of poly-3-hydroxybutyrate with a high molecular weight by methanotroph from methane and methanol

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Journal of Natural Gas Chemistry 2008年第1期17卷 103-109页

作者： Yingxin Zhang Jiaying Xin Linlin Chen hao song Chungu Xia State Key Laboratory for Oxo Synthesis ＆ Selective Oxidation Lanzhou Institute of Chemical Physics Chinese Academy of Sciences Lanzhou 730000 China College of Food Engineering Harbin University of Commerce Harbin 150076 China Graduate University of Chinese Academy of Sciences Beijing 10039 China

Poly-3-hydroxybutyrate （PHB） can be produced by various species of bacteria. Among the possible carbon sources, both methane and methanol could be a suitable substrate for the production of PHB. Methane is cheap and plentiful not only as natural gas, but also as biogas. Methanol can also maintain methanotrophic activity in some conditions. The methanotrophic strain Methylosinus trichosporium IMV3011 can accumulate PHB with methane and methanol in a brief nonsterile process. Liquid methanol （0.1%） was added to improve the oxidization of methane. The studies were carried out using shake flasks. Cultivation was performed in two stages： a continuous growth phase and a PHB accumulation phase under the conditions short of essential nutrients （ammonium, nitrate, phosphorus, copper, iron （Ⅲ）, magnesium or ethylenediamine tetraacetate （EDTA）） in batch culture. It was found that the most suitable growth time for the cell is 144 h. Then an optimized culture condition for second stage was determined, in which the PHB concentration could be much increased to 0.6 g/L. In order to increase PHB content, citric acid was added as an inhibitor of tricarboxylic acid cycle （TCA）. It was found that citric acid is favorable for the PHB accumulation, and the PHB yield was increased to 40% （w/w） from the initial yield of 12% （w/w） after nutrient deficiency cultivation. The PHB produced is of very high quality with molecular weight up to 1.5 × 10^6Da.

关键词： poly-3-hydroxybutyrate methanotrophs methane methanol cultivation biosynthesis high molecular weight

Effect of hydrolysis conditions on hydrous TiO_2 polymorphs precipitated from a titanyl sulfate and sulfuric acid solution

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International Journal of Minerals,Metallurgy and Materials 2012年第7期19卷 642-650页

作者： hao song Bin Liang Li Lu Pan Wu Chun Li Department of Metallurgical Engineering Sichuan University Chengdu 610065 China

The relationship between hydrolysis conditions and hydrous titania polymorphs obtained in a titanyl sulfate and sulfmic acid solu- tion was investigated by X-ray diffraction （XRD）, scanning electron microscopy （SEM）, and high-resolution transmission electron micros- copy （HRTEM）. The results revealed that the feeding rate of the titanyl sulfate stock solution, the concentration of *** acid, and the seed dosage of mtile crystal could significantly affect the hydrolysis rate, thus influencing the titania crystal phase. Hydrous TiO2 in the form of rutile, anatase, or the mixture of both could be obtained in solutions of low titanium concentrations and 2.5wt% to 15wt% sulfuric acid at 100℃. When the hydrolysis rate of titanitma expressed by TiOa was more than or equal to 0.04 g/（***）, the hydrolysate was almost phase-pure anatase, while the main phase state was rutile when the hydrolysis rate was less than or equal to 0.01 g/（***）. With the hy- drolysis rate between 0.02 and 0.03 g/（***）, the hydrolysate contained almost equal magnitude ofrutile and anatase. It seems that although rutile phase is thermodynamically stable in very acidic solutions, anatase is a kinetically stable phase.

关键词： titanium dioxide titanyl sulfate sulfuric acid hydrolysis anatase rutile

Field Study on Indoor Thermal and Luminous Environment in Winter of Vernacular Houses in Northern Hebei Province of China

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Journal of Harbin Institute of Technology(New Series) 2014年第4期21卷 77-83页

作者： Shi-Meng hao Ye-hao song Jun-Jie Li Ning Zhu School of Architecture Tsinghua University Key Laboratory of Eco Planning & Green Building Ministry of EducationTsinghua University

In this paper,a climate-adaptation study of vernacular houses in northern Hebei Province has been conducted based on quantitative field surveys. Three typical vernacular houses with different kinds of building envelopes were selected. The field surveys included investigation on building material and construction,measurement of indoor thermal environment, infrared thermographic study of building envelopes and measurement of luminous environment. The results showed that the indoor air temperatures were below thermal comfort zone from late night till early morning and the horizontal temperature gradient was obvious. The adobe wall showed better thermal performance than the other two. As for the building layout,it is beneficial to put a storeroom on the north side of the house as a temperature buffer zone. Furthermore,due to missing insulation and the informal process of construction,significant amounts of heat escaped from building envelopes,especially from the corner of wall,ceiling and around the openings. The daylight factors on the work plan in the main rooms were accordance with design standards and the level of illuminance met the requirements of family's daily activities.

关键词： thermal environment luminous environment vernacular houses sever cold zone

Synthesis of 2-Phenyl-10-substituted Hymenialdisine Derivatives

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Chemical Research in Chinese Universities 2011年第6期27卷 977-980页

作者： WU Yi WANG Yu QIN Yong song hao Department of Chemistry of Medicinal Natural Products West China School of Pharmacy Sichuan University Chengdu 610041 P. R. China

A series of novel 2-phenyl-10-substituted hymenialdisine derivatives was synthesized via the micro-wave-assisted Suzuki-Miyaura cross-coupling reactions of the 2-phenyl derivative of hymenialdisine and boronic acid, which enabled the successful introduction of electron-donating and electron-withdrawing groups to the 2-phenyl- hymenialdisine derivatives in good yields.

关键词： Hymenialdisine Suzuki-Miyaura reaction 2-Phenyl-10-substituted hymenialdisine derivative