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EFFECT OF PAN-MILLING ON RHEOLOGICAL PROPERTIES OF HIGH DENSITY POLYETHYLENE

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Chinese Journal of Polymer Science 2000年第5期18卷 397-403页

作者： Hua Huang Polymer Research institute, sichuan university,{2.,{3. 四川大学四川成都

The effect of pan-milling on the rheological properties of high density polyethylene (HDPE) was studied. An innovative milling apparatus, viz. an inlaid pan-mill, was used. Melt indexer, capillary rheometer, Haake Rheocord 90 single-screw extruder and Brabender rheometer were used to evaluate the rheological properties of HDPE. HDPE with higher initial molecular weight and larger particle size was easier to degrade under pan-milling stress, as indicated by the melt index. Pressure oscillation in capillary flow occurred at significantly higher shear stress and shear rate for milled HDPE than for unmilled HDPE. The apparent shear viscosity of HDPE decreased with increasing times of milling. After milling, the flow activation energy decreased and thus the sensitivity of viscosity to temperature was reduced. Die pressure and torque during single screw extrusion were reduced significantly after milling. Plasticizing time as measured in a Brabander mixer decreased markedly with increasing milling times.

关键词： high density polyethylene rheological properties pan-milling

Studies on the analytical potential energy function of diatomic molecular ion XY^+ using variational method

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Science china(Physics,Mechanics & Astronomy) 2004年第2期47卷 154-164页

作者： LIU Guoyue1,3. SUN Weiguo1,2.& FENG Hao1 1. institute of Physics,{2., chengdu 610065,{3. 2. College of Chemical Engineering,{2., chengdu 610065,{3. 3. Mianyang Teacher抯 College, Mianyang 62.000,{3. Correspondence should be addressed to Sun Weiguo (e-mail: weiguosun@*** or guoyueliu@ ***) institute of Physics Sichuan University Chengdu China Mianyang Teacher's College Mianyang China College of Chemical Engineering Sichuan University Chengdu China

A new analytical potential energy function for diatomic molecular ion XY+ is proposed based on the energy consistent method (ECM). The Coulomb potential included in the new ionic potential contains multipole corrections, converges quickly and is variationally, changeable. The new potential and the ECM are applied to variationally studying the potential energies of eight electronic states of several diatomic molecular ions: the A2. state of CO+, the X2. g + state of Li 2.+ , the X2. g + state of He 2.+ , the 12.u state of Na 2.+ , the A2.u state of N 2.+ , the X1∑+ state of KrH+, the X2.+ state of SiO+ and the A2. state of SO+ ion. The present results agree excellently with the experiment-based Rydberg-Klein-Rees (RKR) potentials, and are superior to the commonly used Huxley-Murrell-Sorbie (HMS) analytical potentials, and are better in some cases than some quantum mechanicalab initio potentials in the ionic asymptotic and dissociation regions.

关键词： potential energy, diatomic ion, electronic state, variational method.

Accurate studies on the full vibrational energy spectra and molecular dissociation energies for some electronic states of N_(2.molecule

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Science china(Physics,Mechanics & Astronomy) 2005年第4期48卷 385-398页

作者： REN Weiyi1,2. SUN Weiguo1, HOU Shilin3.& FENG Hao4 1. institute of Physics, College of Chemical Engineering,{2., chengdu 610065,{3. 2. institute of Theoretical Physics, Xihua Normal university, Nanchong 63.002.{3. 3. Department of Physics,{3. Oceanography university, Qingdao 2.6003.{3. 4. College of Physics,{2., chengdu 610065,{3. institute of Physics College of Chemical Engineering Sichuan University Chengdu China institute of Theoretical Physics Xihua Normal University Nanchong China Department of Physics China Oceanography University Qingdao China College of Physics Sichuan University Chengdu China

It is usually very difficult to directly obtain molecular dissociation energy De and all accurate high-lying vibrational energies for most diatomic electronic states using modern experimental techniques or quantum theories, and it is also very difficult to give accurate analytical expression for diatomic molecular dissociation energy. This study proposes a new analytical formula for obtaining accurate molecular dissociation energy based on the LeRoy and Bernstein’s energy expression in dissociation limit. A set of full vibrational energy spectra for some electronic states of N2.molecule are studied using the algebraic method (AM) suggested recently, and the corresponding accurate molecular dissociation energies are evaluated using the proposed new formula and high-lying AM vibrational energies. The results show that the AM spectra and the new theoretical dissociation energies agree excellently with experimental data, and thereby providing a new physical approach to generating accurate dissociation energies for electronic states of diatomic molecules.

关键词： vibrational energy, dissociation energy, nitrogen molecule, algebraic method.

Theoretical study of aging effects on LaNi_(5) tritium storage

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Science china(Physics,Mechanics & Astronomy) 2005年第6期48卷 676-686页

作者： PING Feilin1,2. JIANG Gang1, ZHANG Lin2.& ZHU Zhenghe1 1. institute of atomic and {2. Physics,{3., chengdu 610065, china 2. Research Center of Laser Fusion, Mianyang 62.900, china institute of atomic and {2. Physics Sichuan University Chengdu China Research Center of Laser Fusion Miangyang China

The electronic structure and energy of La2.i10H12.and La2.i10H11He (He is at tetrahedral, octahedral or twelve-face polyhedral interstitials) double cells have been calculated using the density functional theory. Their equilibrium structure, energy bands, electronic density of states (DOS) and X-ray diffraction are presented and discussed. The results indicate the helium-3.produced due to the decay of tritium is most possibly sited at twelve-face polyhedral and octahedral interstices and changes the thermodynamic properties of LaNi5 tritide system. The changes due to aging such as the reduction in the isotherm plateau pressure, increase of the isotherm plateau slope, and appearance of deeply trapped hydrogen are caused not only by the lattice expansion, but also by modification of the electronic structure due to the presence of He.

关键词： LaNi5 alloy, density functional theory, electronic structure, aging.

Evaluation of Sustainable Land Management and Diagnosis of Obstacle at County Scale in sichuan Basin:Taking Lezhi County as Example

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Wuhan university Journal of Natural Sciences 2006年第4期11卷 1046-1051页

作者： CHEN Guangjian 1, 2. 3., LIU Qing 1 1. chengdu {2. of Biology, Chinese Academy of Sciences, chengdu 610041, {3.,china 2. Graduate university of Chinese Academy of Sciences, Beijing 100049, china 3. Academy of Land Reconnaissance and Layout of {3. Province , chengdu 61003., {3., china chengdu institute of Biology Chinese Academy of Sciences Chengdu Sichuan China Graduate university of Chinese Academy of Sciences Beijing China Academy of Land Reconnaissance and Layout of sichuan Province Chengdu Sichuan China

This paper established sustainable land resources evaluating indicators fit for hilly area in sichuan Basin, Southwest of china, and evaluated the case of sustainable land management of Lezhi County from 1990 to 2.01. The result showed that the land resource sustainable utilization ability in Lezhi County is belong to Second level （better sustainable）. Secondly, this paper diagnosed some years obstacles of sustainable land management of Lezhi County from base period to goal period and compared the obstacles factors in the indicators system. There were 16 indexes orderly become major affect factor to land sustainable utilization of Lezhi county in indicator system, of which there are 8 obstacles indexes exist both in 1990 and 2.01. The value of obstacles degree of five indicators exceeded 5 in 1990, but in 2.01, only two indicators＇ values were more than 5.

关键词： land resources sustainable land management assessment indicators diagnosis of obstacle

Effect of sediment on concentration of dissolved phosphorus in the Three Gorges Reservoir

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International Journal of Sediment Research 2011年第1期26卷 87-95页

作者： CAO Zhijing~1,ZHANG Xinbao~2.and AI Nanshan~3.institute of Architecture and Environment,{2. university,{3. 610065,china, institute of Mountain Hazards and Environment,Chinese Academy of Sciences,{3. 610041, china, institute of Architecture and Environment,{2. university,{3. 610065,china, Lecturer Institute of Architecture and Environment Sichuan University Chengdu 610065 China Prof. Institute of Mountain Hazards and Environment Chinese Academy of Sciences Chengdu 610041 China Prof. Institute of Architecture and Environment Sichuan University Chengdu 610065 China

Eutrophication and algal bloom has been occurring in the Three Gorges Reservoir ever since the reservoir’s impoundment in *** concentration of dissolved phosphorus(DP) is one of the main controlling factors for algal *** sediment adsorbs DP thereby affecting the concentration of DP. The effect of the sediment reduction on the DP concentration of the Three Gorges Reservoir is discussed in this *** were taken from the Yangtze River and its tributaries,*** Minjiang River and the Tuojiang *** DP concentration of the water samples and the available phosphorus,total phosphorus,and phosphorus-fixing capacity of the sediment samples were *** amount of phosphorus adsorbed by the sediment was about 3.of the total DP load in the Yangtze *** experiment was done in the lab simulating the DP concentration,sediment concentration,and turbulence. The results showed that quite a high amount of DP was adsorbed by the *** adsorption capacity of the sediment was 13. mg/kg and the highest rate of adsorption was 2. mg/kg·*** Xiluodu Dam is located at nearly 1,100 km upstream of the Three Gorges *** Xiloudu Dam will trap sediment and thence reduce the sediment load entering the Three Gorges Reservoir after impoundment in *** is estimated that the sediment reduction due to the Xiluodu Dam may result in an increase of the DP concentration in the Three Gorges Reservoir by 6.8%.

关键词： Dissolved phosphorus Sediment load reduction Three Gorges Reservoir Adsorption capacity Eutrophication

CMC surfaces in the hyperbolic 3.space

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Chinese Science Bulletin 1998年第7期43卷 547-550页

作者： YU Zuhuan 1, 2.and LI Zhenqi 1, 3.1. institute of Mathematics, Fudan {2., Shanghai 2.043., china 2. Department of Mathematics,{3. Union {2., chengdu 610064, china 3. Department of Mathematics, Nanchang {2., Nanchang 3. nstitute of Mathemalics Fudan University Shanghai China Department of Mathematics Sichuan Union University Chengdu China Department of Mathematics Nanchang University Nanchang China

CMC-H surfaces satisfying H≥1 are studied. It is proved that these surfaces possess a natural representation which is a generalization of the Bryant’s result.

关键词： hyperbolic space CMC surface Weierstrass representation.

A first-principles investigation into the hydrogen bond interaction in β-HMX

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Science china(Physics,Mechanics & Astronomy) 2010年第6期53卷 1080-1085页

作者： CHEN Fang 1 ,ZHANG Hong 1,2.ZHAO Feng 3.,MENG ChuanMin 3.& CHENG XinLu 1 1 {2. of atomic and molecular Physics,{3. university,chengdu 610065,china 2.School of Physical Science and Technology,{3. university,chengdu 610065,china 3.Laboratory for Shock Wave and Detonation Physics Research,Southwest {2. of Fluid Physics,china Academy of Engineering Physics,Mianyang 62.900,china institute of atomic and {2. Physics Sichuan University Chengdu China School of Physical Science and Technology Sichuan University Chengdu China Laboratory for Shock Wave and Detonation Physics Research Southwest Institute of Fluid Physics China Academy of Engineering Physics Mianyang China

A theoretical study of structural and electronic properties of β-HMX crystal is performed using density-functional theory(DFT). The total density of states(TDOS) is presented. The atomic orbit projected density of state(PDOS) from the p-type orbit of C,N,O and the s-type orbit of H is discussed. The study by analyzing the PDOS shows that the structure of β-HMX crystal possesses C-H···O intra- and inter-molecular hydrogen-bonding. There exists a hydrogen bonding between H5 -1s and O12.-2. orbits,between H19 -1s and O2. -2. orbits of intra molecules,and between H19 -1s and O2. -2. orbits of inter molecules. The Mulliken population analysis is also made.

关键词： structural property hydrogen bond β-HMX population analysis

The crystal change and "excess heat" produced by long time electrolysis of heavy water with titanium cathode

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原子与分子物理学报 2003年第1期20卷 69-74页

作者： SUN Yue, ZHANG Qing-fu, GOU Qing-quan (institute of atomic and {2. Physics,{3., chengdu 610065, china) institute of atomic and {2. Physics Sichuan University Chengdu 610065

According to the theory given in the paper , the long time electrolysis experiment with titanium cathode in heavy water (D 2.) were done for many times by using the open-loop multi-parameters electrolysis calorimetry system, which is established by us. The specialty is that the cathode is titanium rod and the anode is platinum wire. The early experiment result is still repeated in our recent experiment. The obvious "excess heat" phenomenon can take place only when the electrolysis last more than ten days and amount of "excess heat" increased with the electrolysis time. The "excess heat" can also be obtained from the "boiling to dry" experiment. In the recent experiment, we obtain the results that the amount of "excess heat" is about 3.6 times the input energy, the "excess heat" power is 76.5 W, and the "excess heat" power density is 12..7 W/cm 3. After the electrolysis, the crystal structure of the Ti cathode was measured with x-ray diffraction apparatus. We found that the crystal structure of Ti cathode was changed to face-centered cubic structure of TiD 2.from its hexagonal structure. This result is in agreement with the Gou’s theory mentioned in reference .

关键词：重水电解实验热力学物态变化晶体结构热量测定原子核物理聚变