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Infrageneric relationships of Korean Viola based on eight chloroplast markers

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Journal of Systematics and Evolution 2010年第6期48卷 474-481页

作者： Ki-Oug YOO Su-Kil JANG department of biological Sciences Kangwon National University

Phylogeny and infrageneric relationships were reconstructed for Korean Viola(Violaceae) using eight chloroplast sequences:the atpB-rbcL intergenic spacer,the atpF-H intergenic spacer,the matK gene,the psbA-trnH intergenic spacer,the psbK-I intergenic spacer,the rpl16 intron,the rpoC1 exon 2,and the trnL-trnF *** combined analyses of the eight chloroplast regions suggest that sections Dischidium and Chamaemelanium are monophyletic,whereas section Nomimium is paraphyletic;sections Dischidium and Chamaemelanium form a clade with subsections Hypocarpae and Trigonocarpae of section Nomimium,but unresolved within the clade;two subsections(*** and Vaginatae) of section Nomimium form a clade and are placed between the stem and stemless species group;and subsection Patellares of section Nomimium is monophyletic,and Viola dissecta is diverged first in the clade with high support(BS = 100,PP = 100).Our present results support the subsectional grouping based on morphological characteristics,although discordance remained at the series level.

关键词： chloroplast DNA infrageneric relationships phylogeny series subsection Viola.

Experimental and numerical investigations of scale-up effects on the hydrodynamics of slurry bubble columns

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Chinese Journal of Chemical Engineering 2016年第8期24卷 963-971页

作者： Zhaoqi Li Xiaoping Guan Lijun Wang Youwei Cheng Xi Li department of Chemical and biological Engineering Zhejiang University

Experiments and simulations were conducted for bubble columns with diameter of 0.2 m(180 mm i.d.), 0.5 m(476 mm i.d.) and 0.8 m(760 mm i.d.) at high superficial gas velocities(0.12–0.62 m·s-1) and high solid concentrations(0–30 vol%). Radial profiles of time-averaged gas holdup, axial liquid velocity, and turbulent kinetic energy were measured by using in-house developed conductivity probes and Pavlov tubes. Effects of column diameter, superficial gas velocity, and solid concentration were investigated in a wide range of operating conditions. Experimental results indicated that the average gas holdup remarkably increases with superficial gas velocity, and the radial profiles of investigated flow properties become steeper at high superficial gas velocities. The axial liquid velocities significantly increase with the growth of the column size, whereas the gas holdup was slightly affected. The presence of solid in bubble columns would inhibit the breakage of bubbles, which results in an increase in bubble rise velocity and a decrease in gas holdup, but time-averaged axial liquid velocities remain almost the same as that of the hollow column. Furthermore, a 2-D axisymmetric k–ε model was used to simulate heterogeneous bubbly flow using commercial code FLUENT 6.2. The lateral lift force and the turbulent diffusion force were introduced for the determination of gas holdup profiles and the effects of solid concentration were considered as the variation of average bubble diameter in the model. Results predicted by the CFD simulation showed good agreement with experimental data.

关键词： Bubble column CFD Hydrodynamics Multiphase flow Scaling-up Solid concentration

Crosslink between mutations in mitochondrial genes and brain disorders:implications for mitochondrial-targeted therapeutic interventions

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Neural Regeneration Research 2023年第1期18卷 94-101页

作者： Jaspreet Kalra department of Pharmacology ISF College of PharmacyGhal KalanMogaPunjabIndia department of Molecular Physiology and biological physics University of VirginiaCharlottesvilleVAUSA

At the present,association of mitochondrial dysfunction and progression of neurological disorders has gained significant *** in mitochondrial network dynamics,point mutations,deletions,and interaction of pathogenomic proteins with mitochondria are some of the possible underlying mechanisms involved in these neurological *** genetics,defects in mitochondrial oxidative phosphorylation machinery,and reactive oxygen species production might share common crosstalk in the progression of these neurological *** is of significant interests to explore and develop therapeutic strategies aimed at correcting mitochondrial *** review provided insights on mitochondrial dysfunction/mutations involved in the progression of Alzheimer’s disease,Huntington’s disease,and epilepsy with a special focus on Parkinson’s disease *** with the deleterious effects of mitochondrial mutations in aforesaid neurological disorders,this paper unraveled the available therapeutic strategy,specifically aiming to improve mitochondrial dysfunction,drugs targeting mitochondrial proteins,gene therapies aimed at correcting mutant mtDNA,peptide-based approaches,and lipophilic cations.

关键词： adenosine-triphosphate deficiency mitochondrial fission/fusion mitochondrial mutations neurodegenerative disorders oxidative phosphorylation therapeutic interventions

Field-assisted electron transport through a symmetric double-well structure with spin-orbit coupling and the Fano-resonance induced spin filtering

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Chinese physics B 2008年第7期17卷 2670-2677页

作者：张存喜聂一行梁九卿 department of physics and Institute of Theoretical physics Shanxi University department of physics Yanbei Normal Institute

We have investigated theoretically the field-driven electron-transport through a double-quantum-well semiconductor-heterostructure with spin-orbit coupling. The numerical results demonstrate that the transmission spectra are divided into two sets due to the bound-state level-splitting and each set contains two asymmetric resonance peaks which may be selectively suppressed by changing the difference in phase between two driving fields. When the phase difference changes from 0 to π, the dip of asymmetric resonance shifts from one side of resonance peak to the other side and the asymmetric Fano resonance degenerates into the symmetric Breit-Wigner resonance at a critical value of phase difference. Within a given range of incident electron energy, the spin polarization of transmission current is completely governed by the phase difference which may be used to realize the tunable spin filtering.

关键词： Fano effect Floquet channel spin-orbit coupling

Accelerated effect on Mitsunobu reaction via bis-N-tert-butoxycarbonylation protection of 2-amino-6-chloropurine and its application in a novel synthesis of penciclovir

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Journal of Zhejiang University-Science A(Applied physics & Engineering) 2013年第10期14卷 760-766页

作者： Li-yan DAI Qiu-long SHI Jing ZHANG Xiao-zhong WANG Ying-qi CHEN department of Chemical and biological Engineering Zhejiang University

Solubility of 2-amino-6-chloropurine in Mitsunobu solvents could be significantly improved after its exocyclic amino group is protected via *** bis-Boc protected 2-amino-6-chloropurine also shows excellent activity and N9 selectivity in the coupling with various alcohols by a Mitsunobu ***,a new practical and efficient method is established for the synthesis of penciclovir(PCV) from bis-Boc-2-amino-6-chloropurine 9 and the side chain of 5-(2-hydroxyethyl)-2,2-dimethyl-1,3-dioxane 5—the latter being a more easily prepared cyclic precursor of the diacetate side chain used in the conventional *** coupling of 9 with 5 proceeded regioselectively at a N9 position of purine derivative for a good yield under Mitsunobu conditions.

关键词： 2-amino-6-chloropurine Mitsunobu reaction bis-Boc protection Penciclovir(PCV)

Optimal entropy squeezing sudden generation and its control for an effective two-level moving atom entanglement with the two-mode coherent fields

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Chinese physics B 2009年第6期18卷 2307-2313页

作者：刘小娟周元俊方卯发 department of physics Hunan University of Science and Technology department of physics Hunan Normal University department of physics Nanjing University

From the viewpoint of quantum information, this paper proposes a concept and a definition of the atomic optimal entropy squeezing sudden generation （AOESSG） for the system of an effective two-level moving atom which entangles with the two-mode coherent fields. It also researches the relationship between the AOESSG and entanglement sudden death of the atom-fields, and discusses the influences of atomic initial state on the AOESSG and obtains the system parameter which controls the AOESSG.

关键词： optical entropy squeezing sudden generation effective two-level moving atom entanglement sudden death

Enhanced structural and magnetic properties of microwave sintered Li–Ni–Co ferrites prepared by sol–gel method

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Chinese physics B 2019年第2期28卷 358-362页

作者： NANDeibam Nilima M Maisnam Sumitra Phanjoubam department of physics Oriental College department of physics Oriental CollegeTakyel department of physics Manipur University

The properties of lithium ferrites are very sensitive to chemical composition, synthesis method, and sintering techniques. Li–Ni–Co ferrites with compositional formula Li_(0.45-0.5x)Ni_(0.1)Co_xFe_(2.45-0.5x)O_4, where 0.00 ≤ x ≤ 0.1 in steps of 0.02 were prepared by chemical sol–gel method and sintered by microwave sintering technique. The x-ray diffraction patterns confirmed the formation of single phase with spinel structure in all the samples. The structural parameter *** constant, crystallite size, and x-ray density for these samples were studied and compared with those measured from samples of similar composition prepared by the sol–gel method and sintered by conventional sintering technique. Enhancement in the magnetic properties like Curie temperature, hysteresis parameters was observed by employing sol–gel synthesis combined with microwave sintering. The results obtained and mechanisms involved are discussed in the paper.

关键词： lithium ferrites sol–gel chemistry magnetic properties x-ray diffraction

Identifying the closeness of eigenstates in quantum many-body systems

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Chinese physics B 2017年第8期26卷 66-73页

作者：李海彬杨扬王沛王晓光 department of Applied physics Zhejiang University of Technology department of physics Zhejiang Normal University Zhejiang Institute of Modern physics Department of Physics Zhejiang University

We propose a quantity called modulus fidelity to measure the closeness of two quantum pure states. We use it to investigate the closeness of eigenstates in one-dimensional hard-core bosons. When the system is integrable, eigenstates close to their neighbor or not, which leads to a large fluctuation in the distribution of modulus fidelity. When the system becomes chaos, the fluctuation is reduced dramatically, which indicates all eigenstates become close to each other. It is also found that two kind of closeness, i.e., closeness of eigenstates and closeness of eigenvalues, are not correlated at integrability but correlated at chaos. We also propose that the closeness of eigenstates is the underlying mechanism of eigenstate thermalization hypothesis （ETH） which explains the thermalization in quantum many-body systems.

关键词： quantum chaos thermalization fidelity

Interaction of Pair Particles Mediated by Signal Molecules

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Chinese physics Letters 2016年第1期33卷 140-143页

作者：陈江星郑强黄春云徐江荣应和平 department of physics Hangzhou Dianzi University department of physics Nanjing University department of physics Zhejiang University

A mesoscopic model is set up to study the predatorprey-like phenomenon between two chemically active objects. A target sphere （T） secretes chemical signal molecules that are detected and traced by a hunter sphere （H）. The distribution of signal molecules diffusing around the target is simulated and analyzed. The chemotactic behavior of the hunter along the gradient of signal molecules results in the capture of the target. The dependences of capture time tc on different conditions are focused on. It is found that the values of capture time rely on their initial separation d as a power law tc ∝ d^a. The exponent a depends on decay rate of signal molecules. The capture time increases with the decay rate. The increases of target and hunter size both lead to the decrease of the capture time, which is also shown by the power law behavior. The detailed chemotaxis process is investigated.

关键词： of on is or as by in