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China News Release 2022年第8期 30-32页

作者： Georgios Iliopoulos liu xian 不详

On June 5,Chinese President Xi Jinping exchanged congratulatory messages with Greek President Katerina Sakellaropoulou to celebrate the 50 th anniversary of the establishment of diplomatic relations between the two *** China and Greece are ancient *** half a century,the two countries have gotten along well with each other through dialogues and cooperation,and exhibited broad prospects for win-win cooperation.

关键词： anniversary Greek Open

Effect of temperature on the hydration process and strength development in blends of Portland cement and activated coal gangue or fly ash

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2011年第2期12卷 162-170页

作者： Pei-ming WANG xian-ping liu Key Laboratory of Advanced Civil Engineering Materials (Tongji University) Ministry of Education Shanghai 201804 China

This paper describes the results of an investigation into the effect of the variation of curing temperatures between 0 and 60 °C on the hydration process,pore structure variation,and compressive strength development of activated coal gangue-cement blend(ACGC) . Hardened ACGC pastes cured for hydration periods from 1 to 360 d were examined using the non-evaporable water method,thermal analysis,mercury intrusion porosimetry,and mechanical testing. To evaluate the specific effect of activated coal gangue(ACG) as a supplementary cementing material(SCM) ,a fly ash-cement blend(FAC) was used as a control. Results show that raising the curing temperature accelerates pozzolanic reactions involving the SCMs,increasing the degree of hydration of the cement blends,and hence increasing the rate of improvement in strength. The effect of curing temperature on FAC is greater than that on ACGC. The pore structure of the hardened cement paste is improved by increasing the curing temperature up to 40 °C,but when the curing temperature reaches 60 °C,the changing nature of the pore structure leads to a decrease in strength. The correlation between compressive strength and the degree of hydration and porosity is linear in nature.

关键词： Activated coal gangue (ACG) Fly ash (FA) Blended cement Hydration Curing temperature Strength

The mechanisms underlying long-term potentiation of C-fiber evoked field potentials in spinal dorsal horn

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生理学报 2008年第5期60卷 653-663页

作者： liu xian-Guo Pain Research Center and Department of Physiology Zhongshan Medical School of Sun Yat-sen University Guangzhou 510080China

Long-term potentiation(LTP) of C-fiber evoked field potentials in spinal dorsal horn is first reported in *** then,the mechanisms underlying the long-lasting enhancement in synaptic transmission between primary afferent C-fibers and neurons in spinal dorsal horn have been investigated by different *** this article,the related data were summarized and discussed.

关键词：脊髓电位临床分析神经纤维

The maximal Lyapunov exponent of a co-dimension two-bifurcation system excited by a bounded noise

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Acta Mechanica Sinica 2012年第2期28卷 511-519页

作者： Sheng-Hong Li xian-Bin liu State Key Lab of Mechanics and Control for Mechanical Structures College of Aerospace EngineeringNanjing University of Aeronautics and Astronautics210014 NanjingChina School of Mathematics and Physics Jiangsu University of Science and Technology212003 ZhenjiangChina

In the present paper, the maximal Lyapunov ex- ponent is investigated for a co-dimension two bifurcation system that is on a three-dimensional central manifold and subjected to parametric excitation by a bounded noise. By using a perturbation method, the expressions of the invari- ant measure of a one-dimensional phase diffusion process are obtained for three cases, in which different forms of the matrix B, that is included in the noise excitation term, are assumed and then, as a result, all the three kinds of singular boundaries for one-dimensional phase diffusion process are analyzed. Via Monte-Carlo simulation, we find that the an- alytical expressions of the invariant measures meet well the numerical ones. And furthermore, the P-bifurcation behav- iors are investigated for the one-dimensional phase diffusion process. Finally, for the three cases of singular botmdaries for one-dimensional phase diffusion process, analytical ex- pressions of the maximal Lyapunov exponent are presented for the stochastic bifurcation system.

关键词： Maximal Lyapunov exponent Perturbationmethod. Bounded noise. Diffusion process

Fitness of Encarsia sophia （Hymenoptera： Aphelinidae） parasitizing Trialeurodes vaporariorum and Bemisia tabaci （Hemiptera： Aleyrodidae）

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Insect Science 2011年第1期18卷 84-91页

作者： Chen Luo Tong-xian liu Institute of Plant and Environment Protection Beijing Academy of Agriculture and Forestry Sciences Beijing Key Laboratory of Applied Entomology Northwest A&F University Yangling Shaanxi Province China

Fitness and efficacy of Encarsia sophia （Girault ＆ Dodd）（Hymenoptera： Aphelinidae） as a biological control agent was compared on two species of whitefly （Hemiptera： Aleyrodidae） hosts, the relatively smaller sweetpotato whitefly, Bemisia tabaci （Gennadius） biotype ＇B＇, and the larger greenhouse whitefly, Trialeurodes vaporariorum （Westwood）. Significant differences were observed on green bean （Phaseolus vulgaris L.） in the laboratory at 27 ± 2℃, 55% 4- 5% RH, and a photoperiod of 14 ： 10 h （L ： D）. Adult parasitoids emerging from T. vaporariorum were larger than those emerging from B. tabaci, and almost all biological parameters of E. sophia parasitizing the larger host species were superior except for the developmental times of the parasitoids that were similar when para- sitizing the two host species. Furthermore, parasitoids emerging from T. vaporariorum parasitized more of these hosts than did parasitoids emerging from B. tabaci. We conclude that E. sophia reared from larger hosts had better fitness than from smaller hosts. Those from either host also preferred the larger host for oviposition but were just as effective on smaller hosts. Therefore, larger hosts tended to produce better parasitoids than smaller hosts.

关键词： biological control body size host size oviposition sweetpotato whitefly

Exploitation of fractured shale oil resources by cyclic CO_2 injection

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Petroleum Science 2018年第3期15卷 552-563页

作者： Tao Wan Hong-xian liu Faculty of Petroleum China University of Petroleum(Beijing)

With shale oil reservoir pressure depletion and recovery of hydrocarbons from formations, the fracture apertures and conductivity are subject to reduction due to the interaction between stress effects and proppants. Suppose most of the proppants were concentrated in dominant fractures rather than sparsely allocated in the fracture network, the fracture conductivity would be less influenced by the induced stress effect. However, the merit of uniformly distributed proppants in the fracture network is that it increases the contact area for the injection gas with the shale matrix. In this paper, we address the question whether we should exploit or confine the fracture complexity for CO2-EOR in shale oil reservoirs. Two proppant transport scenarios were simulated in this paper： Case 1-the proppant is uniformly distributed in the complex fracture system, propagating a partially propped or un-propped fracture network; Case 2-the proppant primarily settles in simple planar fractures. A series of sensitivity studies of the fracture conductivity were performed to investigate the conductivity requirements in order to more efficiently produce from the shale reservoirs. Our simulation results in this paper show the potential of CO2 huff-n-puff to improve oil recovery in shale oil reservoirs. Simulation results indicate that the ultra-low permeability shales require an interconnected fracture network to maximize shale oil recovery in a reasonable time period. The well productivity of a fracture network with a conductivity of 4 mD ft achieves a better performance than that of planar fractures with an infinite conductivity. However, when the conductivity of fracture networks is inadequate,the planar fracture treatment design maybe a favorable choice. The available literature provides limited information on the relationship between fracture treatment design and the applicability of CO2 huff-n-puff in very low permeability shale formations. Very limited field test or laboratory data

关键词： CO2-enhanced oil recovery Huff-n-puff Shale oil reservoirs Recovery simulation

Update of transcatheter valve treatment

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2013年第8期14卷 670-675页

作者： xian-bao liu Jian-an WANG Cardiovascular Key Lab of Zhejiang Province Department of Cardiology the Second Affiliated Hospital School of Medicine Zhejiang University

Transcatheter valve implantation or repair has been a very promising approach for the treatment of valvular heart diseases since transcatheter aortic valve implantation (TAVI) was successfully performed in 2002. Great achievements have been made in this field (especially TAVI and transcatheter mitral valve repair-MitraClip system) in recent years. Evidence from clinical trials or registry studies has proved that transcatheter valve treatment for valvular heart diseases is safe and effective in surgical high-risk or inoperable patients. As the evidence accumulates, transcatheter valve treatment might be an alterative surgery for younger patients with surgically low or intermediate risk valvular heart diseases in the near future. In this paper, the updates on transcatheter valve treatment are reviewed.

关键词：心脏疾病临床冠状动脉调查结果

An Inherent Chiral Calix[4]arene Bearing Chiral Groups without Forming Sub-ring

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Chinese Chemical Letters 2006年第9期17卷 1169-1172页

作者： xian xian liu Yan Song ZHENG Wan Ling MO Departmentof Chemistry Huazhong University of Science and Technology Wuhan 430074 Department of Chemistry Guilin Normal College Guilin 541001 不详

The NMR spectra revealed that the calixarene frame of 1, 3-disubstituted calix[4]arenes beating optically active groups is asymmetric, even without the formation of a sub-ring. This inherent chirality arises from the interaction of the two chiral groups, which hinder the substituents＇ free rotation. Thus, these chiral calix[4]arenes display good chiral recognition ability.

关键词： Calixarene inherent chirality chiral recognition.

Oviposition preference, larval performance and adaptation of Trichoplusia ni on cabbage and cotton

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Insect Science 2015年第2期22卷 273-282页

作者： Yuan-Xi Li Tong-xian liu Department of Entomology College of Plant Protection Nanjing Agricultural University Nanjing State Key Laboratory of Crop Stress Biology for Arid Areas and Key Laboratory of Crop IPM for the Loess Plateau Ministry of Agriculture of China at Northwest A&F University Yangling Shaanxi China

Most female herbivores ensure to lay eggs where their offspring can develop successfully. The oviposition preferences of females affect strategies in pest management. In this study, the performance of two cohorts of Trichoplusia ni larvae on cabbage and cotton （after they had been transferred from their original host plants） were investigated. The preferences of female moth ovipositing and larval feeding on these two host plants were observed. The results indicated that plants significantly affected oviposition preference of the female adults and development and survival of larvae of T. ni. All females preferred to lay eggs on cabbage than cotton regardless from which host they originated. The detrimental effects of cotton on the development and survival of T. ni larvae originated from cabbage （CaTn） increased with the increase of the larval age when they were transferred. In addition, the host plant change did not significantly affect the development and survival of larvae of T. ni originating from cotton （CoTn）. Larvae of CaTn preferred cabbage plants as compared to cotton plants, whereas larvae of CoTn did not show a significant choice. Although the adult females preferred laying eggs on cabbage, they did not show preferences between cotton and cabbage in a Y-tube olfactometer test. The hypothesis of oviposition preference and performance of larvae was supported by the results of CaTn, whereas they not supported by those from CoTn. Based on these results, the strategy to manage this serious pest was discussed.

关键词： cabbage looper development larval choice oviposition preference

The Structure and Elastic and Thermodynamic Properties of Cubic-NbH_(2) under High Pressures from First-Principles Calculations

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Chinese Physics Letters 2013年第6期30卷 161-164页

作者： liu xian-Kun TANG Bin Institute of Nuclear Physics and Chemistry China Academy of Engineering PhysicsCAEPMianyang 621900

NbH_(2) hydride is an important material in hydrogen storage ***,until now there have been no experimental and theoretical data on the elastic and thermodynamic *** structure and thermodynamic properties of cubic-NbH_(2) under high temperatures and pressure are investigated by first-principles study based on the pseudo-potential plane-wave density functional theory method using the generalized gradient approximation and quasi-harmonic Debye *** results show that the calculated structural parameters of NbH2 are in good agreement with the available experimental results and other theoretical *** obtained elastic constants satisfy the requirement for mechanical stability,indicating that the NbH_(2) crystal is stable in the investigated pressure and temperature *** the quasi-harmonic Debye model,in which the phononic effects are considered,the thermodynamic properties of NbH_(2),such as the thermal expansion coefficient and the heat capacity dependence of temperature and pressure in the ranges 0–1100K and 0–70GPa,are also obtained,respectively.

关键词： thermodynamic Debye Elastic