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Influence of Isotope on Shell Effects of Pre-scission Particle Evaporation

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Communications in Theoretical Physics 2005年第2X期44卷 343-346页

作者： YE Wei chen Na Department of Physics Southeast University Nanjing 210096 China Department of Applied Mathematics Nanjing University of Finance & Economics Nanjing 210003 China

The shell effects on the particle evaporation prior to fission for three Pb isotopes, ^204Pb, ^208Pb, and ^212pb,as well as three Sn isotopes, ^128Sn, ^132Sn, and ^136Sn, are explored by a diffusion model. Calculations show that the magnitude of shell effects in the emission of particles changes with the neutron-to-proton ratio N/Z of these fissioning nuclei, and this change is affected significantly by the spin and excitation energy of the system. It is shown that high angular momentum enhances the dependence of shell effects on the N/Z while high excitation energy weakens such a dependence.

关键词： isotopic effect shell effect pre-scission particle emission Smoluchowski equation

A Note on Schwarz-Pick Estimate

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Chinese Annals of Mathematics,Series B 2010年第3期31卷 343-346页

作者： Yang LIU Zhihua chen Department of Mathematics Zhejiang Normal University Jinhua 321004 Zhejiang China. Department of Mathematics Tongji University Shanghai 200092 China

A Schwarz-Pick estimate of higher order derivative for holomorphic functions with positive real part on Bn is presented. This improves the earlier work on Schwarz-Pick estimate of higher order derivatives for holomorp... 详细信息

关键词： Schwarz-Pick estimate Holomorphic function Taylor expansion

The interaction of defects in titanium:A molecular dynamics study

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Nuclear Science and Techniques 2010年第5期21卷 271-274页

作者： chen Min HOU Qing Key Subject Laboratory of National defense for Radioactive Waste and Environmental Security Southwest University of Science and Technology Mianyang 621010 China Key Laboratory for Radiation Physics and Technology of Ministry of Education Institute of Nuclear Science and Technology Sichuan University Chengdu 610064 China

Behaviors and properties of helium in titanium were explored by molecular dynamics(MD) simulation in this *** influence of He number,vacancy number and He density(ratio of helium to vacancy) on the thermal stability of HenVm clusters(where n and m denote the number of He atoms and vacancies) were ***,interactions among He atoms,SIA atoms and vacancies were *** results demonstrate that the binding energies of an interstitial helium atom primarily depend on He and vacancy numbers rather than the helium-to-vacancy ratio(n/m).It is different from the previous report of other *** binding energies of an isolated vacancy and a self-interstitial titanium atom depend on both the number of helium atoms and the helium-to-vacancy ratio(n/m) of *** thermal stability of clusters is decided by the competitive processes among thermal emissions of vacancy,SIA and helium atom.

关键词：分子动力学相互作用缺陷钛氦原子热稳定性间隙原子合金性能

The effects of the synthetic nocistatin on blood vessel activities

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Chinese Science Bulletin 2001年第8期46卷 675-678页

作者： Qiang chen Yong chen Lixiang chen Dingjian Yang Shouliang Dong Rui Wang Lanzhou Univ Sch Life Sci Dept Biochem & Mol Biol Lanzhou 730000 Peoples R China

Nocistatin was synthesized by the solid-phase peptide synthesis method. Its effects on rat systemic arterial pressure; rat hindquarter vascular bed resistance; tension of rabbit pectoral, abdominal, femoral aorta muscle strips without endothelium; and nociceptin induced decreases of rat systemic arterial pressure were determined. The results showed that nocistatin can increase the systemic arterial pressure, increase the hindquarter vascular bed resistance and induce the contraction significantly of abdominal, femoral aorta muscle strips without endotheiium; it has no significant effect on tension of pectoral aorta muscle strips, it cannot antagonize significantly the decrease of rat systemic arterial pressure induced by nociceptin. These results suggest that nocistatin has some important effects on blood vessel activities.

关键词： solid-phase polypeptide synthesis nocistatin nociceptin systemic blood pressure hindquarter vascular bed resistance blood vessel muscle strip.

Capturing and tracking of building area based on structure saliency in airborne remote sensing video

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Science China(Information Sciences) 2015年第4期58卷 176-178页

作者： FENG Jing BI FuKun chen Liang ZHANG FeiFei chen He School of Information and Electronics Beijing Institute of Technology College of Information Engineering North China University of Technology

Dear editor,Object capturing and tracking in airborne remote sensing video is one of the hottest research topics,which is widely used in disaster monitoring and rescue and vehicle *** of the high realtime requirement ... 详细信息

关键词： Capturing and tracking of building area based on structure saliency in airborne remote sensing video SIFT area

Toxicity mechanisms of photodegraded polyvinyl chloride nanoplastics on pea seedlings

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Frontiers of Environmental Science & Engineering 2024年第4期18卷 111-124页

作者： Hao Wu Beibei He Bocheng chen An Liu College of Chemistry and Environmental Engineering Shenzhen UniversityShenzhen 518060China

Nanoplasctics(NPs),which are very small in particle size,exert toxic effect to ***,compared to original NPs,photodegraded NPs would pose higher *** is because their relatively higher specific surface areas and the presence of additives which can more easily *** original NPs and aged NPs affect plant growth has not been widely *** work chose polyvinyl chloride NPs(PVC-NPs)that were subjected to up to 1000 h UV light radiation to explore the impact of PVC-NPs on the growth of pea seedlings(Pisum Sativum L.).The results indicated the existence of PVC-NPs with longer UV light radiation time and higher concentrations had more negative influences on pea seedlings’growth such as germination rate(decreased by 10.6%–22.5%),stem length(decreased by 2.8%–8.1%),dry weight(decreased by 6.3%–7.1%)and fresh weight(decreased by 6.7%–14.8%).It was also noted that photodegraded PVC-NPs resulted in damage to leaf stomata and roots,hindering photosynthesis and absorption of nutrients and hence the decrease in chlorophyll and soluble sugar *** to transcriptomic investigation results,the presence of aged PVC-NPs primarily influenced protein processing in endoplasmic reticulum(upregulated metabolic pathway)and phenylpropanoid biosynthesis(downregulated metabolic pathway)of pea *** results provide an in-depth understanding of how NPs influence the growth of plants.

关键词： Nanoplasctics Polyvinyl chloride Toxicity mechanisms Plant growth

DESCRIPTION AND PREDICTION OF CATASTROPHE OF VIBRATION STATE FOR FAULTY ROTORS

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Transactions of Nonferrous Metals Society of China 1996年第1期6卷 130-134页

作者： chen Anhua Zhong Jue Department of Mechanical Engineering Central South University of Technology Changsha 410083

A sudden increase of vibration amplitude with no foreboding often results in an abrupt breakdown of a mechanical *** catastrophe of vibration state of a faulty rotor is a typical nonlinear phenomenon,and very difficult to be described and predicted with linear vibration *** the basis of nonlinear vibration and catastrophe theory,fhe eatastrophe of the vibration amplitude of the faulty rotor is described;a way to predict its emergence is developed.

关键词： mechanical fault diagnosis and prediction cusp catastrophe model nonlinear vibration rotor

Synthesis and luminescence properties of red-emitting M_2Si_5N_8:Eu^(2+)-based(M=Ca,Sr,Ba) phosphors by a simple nitrate reduction

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Science China(Physics,Mechanics & Astronomy) 2014年第3期57卷 433-436页

作者： chen Changcheng XIE ErQing School of Materials Science and Engineering Georgia Institute of Technology School of Physical Science and Technology Lanzhou University

M2SisN8：Eu2＋-based （M=Ca, Sr, Ba） red-emitting phosphors are fabricated at relatively low temperature （1200℃） and atmos- pheric pressure using a simple solid-state reaction process. Several processing parameters are systematically investigated to optimize the phosphors structural characterization and photoluminescence performance, including the amount of europium and the properties of the precursor materials. The as-prepared M2SisNs：Eu2＋-based （M=Ca, Sr, Ba） phosphors are orange in color and are intensively emitted in the red region of 580-670 nm under 465 nm excitation.

关键词： M2SisN8:Eu2+-based phosphors nitrate reduction luminescence

Barrier effects on the optoelectronic properties of GaN-based irregular multiple quantum wells for dichromatic white LEDs

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Science China(Technological Sciences) 2011年第1期54卷 6-10页

作者： chen GenXiang LU HuiMin Institute of Lightwave Technology Beijing Jiaotong University Beijing 100044 China

The GaN-based irregular multiple quantum well (IMQW) structures for dichromatic white light-emitting diodes (LEDs) are assembled by two different types of QWs emitting complementary blue and yellow light. The electronic and optical properties of the designed GaN-based IMQW structures are investigated in details by fully considering the effects of strain,well-coupling,valence band-mixing and polarization effect by employing a newly modified theoretical model based on the k·p theory. The influences of the height and thickness of the barrier between blue QWs and yellow QWs together with the polarization effect on the optoelectronic properties of GaN-based IMQW structure are analyzed. Numerical results show that the ratio of the two color lights emmited from the IMQW structure for dichromatic white LED can be tuned by changing the height and thickness of the barrier between two types of QWs.

关键词： irregular multiple quantum wells GaN-based materials white fight-emitting diodes