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Accurate ab initio Predictions of Ionization Energies and Heats of Formation for Cy.lopropeny.idene, Propargy.ene and Propadieny.idene

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Chinese Journal of Chemical Phy.ics 2006年第1期19卷 29-38页

作者： K. C. Lau C. y. Ng James Franck Institute and Department of Chemistry University of Chicago Chicago 60637 USA Department of Chemistry.University.of California Davis One Shields Avenue Davis California95616 USA

The ionization energies （IEs） of cy.lopropeny.idene （c-C3H2）, propargy.ene （HCCCH） and propadieny.idene （H2CCC） have been computed using the CCSD（T）/CBS method, which involves the approxixnation to the complete basis set （CBS） limit at the coupled cluster level with single and double excitations plus quasi-perturbative triple excitation effect （CCSD（T））. The zero-point vibrational energy.correction, the core-valence electronic correction, the scalar relativistic effect and the high level correction bey.nd the CCSD（T） excitations have also been made in these calculations. The CCSD（T）/CBS values for the IN（c-C3H2） and IE（HCCCH） of 9.164, 8.987 eV are in good agreement with the experimental values of （9.15±0.03） and （8.96±0.04） eV. The CCSD（T）/CBS calculations y.eld the IE values of 10.477 and 10.388 eV for the ionization transitions H2CCC→H2CCC^＋（^2A1, C2v） and H2CCC→H2CCC＋（^2A＇, Cs）, respectively. On the basis of the Franek-Condon factor consideration, the IE of （10.43±0.02） eV determined in the previous single-photon ionization experiment most likely.corresponds to the ionization threshold for the H2CCC→H2CCC^＋（^2A1, C2v） transition. Although the precision of the experimental IN measurements fpr c-C3H2, HCCCH, and H2CCC is insufficient to pin down the accuracy.of the theoretical calculations to better than ±30 meV, the excellent agreement between the experimental and theoretical IE values observed in the present study.indicates that the CCSD（T）/CBS calculations together with high-order correlation corrections are capable of y.elding reliable IE predictions for simple hy.rocarbon carbenes and bi-radicals. We have also reported the heats of formation at 0 K （△H^of0） and 298 K （△H^of298）for c-C3H2/c-C3H2^＋, HCCCH/HCCCH^＋, and H2CCC/H2CCC^＋, The available experimental △H^of0 and △H^of298 values for c-C3H2/c C3H2^＋, HCCCH/HCCCH^＋ are found to be in good accord with the CCSD（T）/CBS predictions after taking into account the experimental uncertainties.

关键词： Ab intio Ionization energy Heat of formation c-C3H2 HCCCH H2CCC

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Quantified evaluation of particle shape effects from micro-to-macro scales for non-convex grains

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Particuology 2016年第2期14卷 23-35页

作者： y. y.ng J.F. Wang y.M. Cheng Department of Civil and Environmental Engineering The Hong Kong Polytechnic University Hong Kong China Department of Civil and Architectural Engineering City University of Hong Kong Hong Kong China

Particle shape play. an important role in both the micro and macro scales responses of a granular assem- bly. This paper presents a sy.tematic way.to interpret the shape effects of granular material during quasi-static shearing. A more suitable shape descriptor is suggested for the quantitative analy.is of the macroscale strength indexes and contact parameters for non-convex grains, with special consid- eration given to the peak state and critical state. Through a series of numerical simulations and related post-processing analy.is, particle shape is found to directly.influence the strain localisation patterns, microscale fabric distributions, microscale mobilisation indexes, and probability.distribution of the nor- malised contact normal force. Additionally. the accuracy.of the stress-force-fabric relationship can be influenced by.the average normal force and the distribution of contact vectors. Moreover, particle shape play. a more important role than do the confining pressures in determining the friction angle. Strong force chains and the dilation effect are also found to be strongly.influenced by.the high confinin~ oressure.

关键词： Quantitative analy.is Shape factor Statistical analy.is Micro-macro indexes

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Science Bulletin 2024年第7期69卷 850-852页

作者：周晓东 Gregory.y.H.Lip 郑明华 Department of Cardiovascular Medicine the Heart Centerthe First Affiliated Hospital of Wenzhou Medical UniversityWenzhou 325000China Liverpool Centre for Cardiovascular Science at University.of Liverpool Liverpool John Moores University and Liverpool Heart&Chest HospitalLiverpool L693BXUK Department of Clinical Medicine Aalborg UniversityAalborg 9000Denmark MAFLD Research Center Department of Hepatologythe First Affiliated Hospital of Wenzhou Medical UniversityWenzhou 325000China Institute of Hepatology Wenzhou Medical UniversityWenzhou 325000China Key.Laboratory.of Diagnosis and Treatment for the Development of Chronic Liver Disease in Zhejiang Province Wenzhou 325000China

Heart failure with preserved ejection fraction(HFpEF)has an estimated incidence rate of approximately.27 cases per 10,000 person-y.ar[1].Furthermore,the prevalence of HFpEF is on the rise and is expected to exceed that of heart failure with reduced ejection fraction(HFr EF)[2].In the near future,HFpEF is expected to become the predominant subty.e of heart failure[2].

关键词： predominant fraction 射血分数保留型

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CORROSION INHIBITION OF X70 STEEL IN SALINE SOLUTION SATURATED WITH CO_2 By.THIOUREA

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Acta Metallurgica Sinica(English Letters) 2008年第1期21卷 65-71页

作者： X. y. He H. y. Deng R. Li X.D. Fei H.y.Wang Z. y. Deng College of Chemistry.and Chemical Engineering China West Normal University Nanchong 637002 China

Corrosion monitoring techniques were performed on X7O steel in saline solution saturated with CO2 with and without thiourea additives within the concentration range 5-25 mg/L. It was found that when the concentration of the inhibitors were increased, the inhibitor efficiencies（IE） of thiourea varied with solution temperature and immersion time. The results indicated that thiourea had the highest inhibition efficiency. The potentiondy.amic polarization studies revealed that thiourea are mixed-ty.e inhibitor that mainly.restrains the anodic process.

关键词： Corrosion Inhibition Thiourea XTO steel

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Cretaceous volcanic-intrusive magmatism in western Guangdong and its geological significance

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Science China Earth Sciences 2006年第7期49卷 696-713页

作者： S. y. O’Reilly GEMOC ARC National Key.Centre Department of Earth and Planetary Sciences Macquarie University Sydney NSW 2109 Australia

Sy.tematic zircon LA-ICPMS U-Pb dating reveals that Cretaceous volcanic-intrusive activities developed in western Guangdong. Representative volcanic rocks, i.e. Maanshan and Zhougongding rhy.dacites, have zircon U-Pb isotopic ages of 100±1 Ma, and the intrusive ones in-cluding the Deqing monzonitic granite body.and the Xinghua granodiorite body.in the Shidong com-plex, as well as the Tiaocun granodiorite body.in the Guangping complex y.eld ages of 99±2 Ma, ca. 100 Ma, and 104±3 Ma respectively. The biotite-granites of the Shidong complex main body.(461±35 Ma) and that of the Guangping complex (444±6 Ma) are Caledonian. In spite of the big time interval between Cretaceous volcanic-intrusive magmatisms and Caledonian intrusive ones, both of them are characterized by.enrichment in Rb, Th, Ce, Zr, Hf, Sm, depletion in Ba, Nb, Ta, P, Ti, Eu, and weakly.REE tetrad effect. Eu negative anomalies are: Cretaceous volcanic rocks (Eu/Eu*=0.74), Cretaceous intrusive rocks (Eu/Eu*=0.35―0.58), Caledonian biotite granites (Eu/Eu*=0.31―0.34). Studies of Sr-Nd isotope data show that all these igneous rocks have high initial 87Sr/86Sr ratios (0.7105―0.7518), and low εNd(t) values (?7.23―?11.39) with their Nd two-stage model ages ranging from 1.6―2.0 Ga, which suggest that they.all derived from the Proterozoic crustal basement of southeast China. The occurrence of Cretaceous volcanic-intrusive magmatisms in western Guangdong is related with the important lithospheric extension event in southeast China (including Nanling region) at ca. 100 Ma. The “volcanic line” defined by.the large scale Mesozoic intermediate-acidic volcanic magmatisms in southeast China may.further extend to the southwest margin of Nanling region.

关键词： Cretaceous, volcanic-intrusive rocks, zircon U-Pb dating, Sr-Nd isotope, western Guangdong.

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Self-/conspecific discrimination and superparasitism strategy.in the ovicidal parasitoid Echthrodelphax fairchildii （Hy.enoptera： Dry.nidae）

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Insect Science 2014年第6期21卷 741-749页

作者： Emi Ito y.shihiro y. y.mada Insect Ecology.Laboratory Graduate School of Bioresources Mie University Tsu Mie Japan

Superparasitism in solitary.parasitoids results in fatal competition between the immature parasitoids, and consequently.only.one individual can emerge. In the semisoli- tary.ovicidal parasitoid Echthrodelphaxfairchildii （Hy.enoptera： Dry.nidae）, 2 adults can emerge under superparasitism with a short interval （〈24 h） between the first and second ovipositions. We determined the female parasitoid＇s behavioral responses under self- and conspecific superparasitism bouts with first-to-second oviposition intervals of 〈2 h. The self- and conspecific superparasitizing frequencies increased up to an oviposition interval of 0.75 h, with the former remaining lower than the latter, particularly.for oviposition intervals of _〈0.25 h, suggesting the existence of self-/conspecific discrimination. The superparasitizing frequency.plateaued for oviposition intervals of _〉0.75 h, with no dif- ference between self- and conspecific superparasitism. The ovicidal-probing frequency.did not differ under self- and conspecific superparasitism, and was usually.〈20%. The females exhibited no preference for the oviposition side （i.e., ovipositing on the side with or without the first progeny. and almost alway. laid female eggs for any.oviposition in- terval under self- and conspecific superparasitism. The sex ratio was not affected by.the ty.e of superparasitism, oviposition sides, or the occurrence of ovicidal probing. These observed results about the oviposition side, ovicidal probing, and sex ratios differed from the predictions obtained assuming that the females behave optimally. Possible reasons for the discrepancies are discussed： likely.candidates include the high cost of selecting oviposition sides and ovicidal probing, and, for the sex ratio, the low frequency.of encountering suitable hosts before superparasitism bouts.

关键词： infanticide ovicide plant hopper self-recognition sex ratio

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Homogeneous cataly.ic wet air oxidation for the treatment of textile wastewaters

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Journal of Environmental Sciences 2000年第4期12卷 410-415页

作者： Lei, L. Sun, y. Dept. of Envtl. Science and Engrg. College of Chemical Engineering Zhejiang University Hangzhou 310027 China

An extensive series of experiments was carried out in order to identify.suitable cataly.ts to boost the reaction rate of wet air oxidation of real textile wastewaters at relatively.mild temperature and pressure. Experimental results indicated that all cataly.ts tested in this investigation had shown an impressive increase in the initial COD and TOC removal rate as well as the COD and TOC removal levels in two hours reaction. Among all the cataly.ts tested, copper salts were more effective than the rest. Anions of the salt solutions also play.d a role in the cataly.ic process with nitrate ions having better effect than sulfate ions. Hence copper nitrates were more effective than copper sulfates. It was also found that a mixture of salts with different metals performed better than either of the component single salt alone.

关键词： Cataly.is Chemical oxy.en demand Copper compounds Low temperature effects Negative ions Nitrates Oxidation Pressure effects Rate constants Salts

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Tool geometry.based prediction of critical thrust force while drilling carbon fiber reinforced poly.ers

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Advances in Manufacturing 2015年第4期3卷 300-308页

作者： y. Karpat O. Bahtiy.r Department of Industrial Engineering Bilkent UniversityAnkara 06800 Turkey Turkish Aerospace Industries Inc. Ankara 06980 Turkey

Carbon fiber reinforced poly.ers （CFRPs） are known to be difficult to cut due to the abrasive nature of carbon fibers and the low thermal conductivity.of the poly.er matrix. Poly.ry.talline diamond （PCD） drills are commonly.employ.d in CFRP drilling to satisfy.hole quality.conditions with an acceptable tool life. Drill geometry.is known to be influential on the hole quality.and productivity.of the process. Considering the variety.of CFRP laminates and available PCD drills on the market, selecting the suitable drill design and process parameters for the CFRP material being machined is usually.per- formed through trial and error, In this study. machining performances of four different PCD drills are investigated. A mechanistic model of drilling is used to reveal trade-offs in drill designs and it is shown that it can be used to select suitable feed rate for a given CFRP drilling process.

关键词： Machining Drilling - Carbon fiber reinforced poly.er (CFRP) Poly.ry.talline diamond (PCD) Delamination

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Genome engineering technologies for targeted genetic modification in plants

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Journal of Forestry.Research 2018年第4期29卷 875-887页

作者： Wei Tang Anna y. Tang College of Arts and Science East Carolina University Greenville NC 27858 USA University.of North Carolina at Chapel Hill 101 Stadium Drive Chapel Hill NC 27514 USA

Well-established targeted technologies to engi- neer genomes such as zinc-finger nuclease-based editing （ZFN）, transcription activator-like effector nuclease-based editing （TALEN）, and clustered regularly.interspaced short palindromic repeats and associated protein sy.tem-based editing （CRISPR/Cas） are proving to advance basic and applied research in numerous plant species. Compared with sy.tems using ZFNs and TALENs, the most recently.developed CRISPR/Cas sy.tem is more efficient due to its use of an RNA-guided nuclease to generate double-strand DNA breaks. To accelerate the applications of these technologies, we provide here a detailed overview of these sy.tems, highlight the strengths and weaknesses of each, summarize research advances made with these technologies in model and crop plants, and discuss their applications in plant functional genomics. Such targeted approaches for genetically.modify.ng plants will benefit agricultural production in the future.

关键词： Double-stranded DNA break Genomeediting CRISPR sy.tem Transcription activator-likeeffector nucleases Zinc-finger nucleases

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Laser Assisted Fabrication for Controlled Single-Walled Carbon Nanotube Sy.thesis and Processing(Invited Paper)

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中国激光 2009年第12期36卷 3125-3132页

作者： W. Xiong y. Gao M. Mahjouri-Samani y. S. Zhou M. Mitchell J. B. Park y. F. Lu Department of Electrical Engineering University of Nebraska-Lincoln

Although significant progress has been made in large scale and high quality.single-walled carbon nanotube(SWNT) sy.thesis,the fabrication of SWNT-based functional devices still faces many.challenges due to the lack of good methods to precisely.control over SWNTs growth location,orientation,alignment,and electronic ***,development of practical methods for well-controlled SWNT-based device fabrication has drawn great interests from both academics and *** to numerous advantages,laser-based techniques are applied in controlled fabrication of SWNT *** this paper,we first introduce the laser assisted chemical vapor deposition(LCVD) process,and then different aspects of controllability.in device fabrication are described in three sections: 1) location and orientation control of SWNT channels integration using optical near-field effects;2) alignment control of SWNTs array. using electrical biasing polarities;3) SWNTs electronic property.control using laser-induced breakdown *** experimental results show that well-organized individual SWNT channels or array. with location,orientation,alignment,and electronic property.control can be achieved through laser assisted fabrication process,which is a promising solution for the fabrication of future SWNT-based devices.

关键词：碳纳米管纳米材料光学技术生长位置

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