TRITON-(HE)-H-3 RELATIVE AND DIFFERENTIAL FLOWS AND THE HIGH DENSITY BEHAVIOR OF NUCLEAR SYMMETRY ENERGY

Using a transport model coupled with a phase-space coalescence after-burner we study the triton-He-3 relative and differential transverse flows in semi-central Sn-132 + Sn-124 reactions at a beam energy of 400 MeV/nucleon. We find that the triton-He-3 pairs carry interesting information about the density dependence of the nuclear symmetry energy. The t-He-3 relative flow can be used as a particularly powerful probe of the high-density behavior of the nuclear symmetry energy.

CSRm 束流横向耦合研究

在环形加速器中，横向耦合表现为粒子在径向和轴向两方向振荡间的能量交换。耦合效应会对束流品质产生一系列的弊端影响，所以束流耦合的研究成为加速器研究中的一个必要的课题。 本论文首先对兰州重离子加速器冷却储存环（HIRFL-CSR）的结构作了简单说明，交代了电子冷却装置的位置及组成，说明了螺线管场在装置中的作用及其耦合效应，继而提出研究横向耦合对HIRFL-CSR主环的重要性和必要性。 接着本论文对横向耦合运动的基础理论作了推导和描述，提出以传输矩阵研究束流相空间运动的方法，分析了横向耦合对束流发射度的影响及横向耦合的匹配条件，并详细分析了束流的径向和轴向耦合振荡在和、差共振时的稳定性情况。 最后，根据储存环主环（CSRm）的实际情况，模拟计算了CSRm中多种耦合源在不同工作点时的束流稳定情况，比较了磁铁的纵向角安装误差与螺线管场对束流耦合效应的大小；并且模拟了冷却段螺线管场对束流发射度和动力学孔径的横向耦合效应，通过模拟提出了合适的耦合补偿方案，这样以减少由于耦合造成的束流损失

HIRFL剥离器后切束线物理设计

HIRFL is a tandem cyclotron complex for heavy ion. On the beam line between SFC and SSC, there is a stripper. Behind it, the distribution of charge states of beam is a Gauss distribution. The equilibrium charge state Q_0 is selected by 1BO2(a 50° dipole behind the stripper) and delivered to SSC. One of two new small beam line (named SLAS) after 1B02 will be builded in or der to split and deliver the unused ions of charge states (Q_0 ± n) to aspecific experimental area. Q_0 ± n ions are septumed and separated from initial(Q_0) ion beam by two septum magnets SM1, SM2. The charge state selected by SM1 will be Q_0 ± 1(6 ≤ Q_0 < 17), Q_0 ± 2(17 ≤ Q_0 < 33) and Q_0 ± 3 (Q_0 ≥ 33) forming a beam in one of the two possine new beam line with the stripping energy of (0.2 to 9.83 Mev/A), an emittance of 10π mm.mrad in the two transverse planes and an intensity ranging from 10~(11) pps for z ≤ 10 to some 10~5 pps for the heaviest element. Behind SM2, a few transport elements (three dipoles and seven qudrupoles) tra nsport Q_0 ± n beam to target positions T1, T2 (see fig. 1) and generate small beam spots (φ ≤ 4mm, φ ≤ 6mm). The optics design of the beam line has been done based on SLAC-75 (a first and second - order matrix theory). beam optics calculation has been worked out with the TRANSPORT program. The design is a very economical thinking, because without building a new accelerator we can obtain a lower energy heavy ion beam to provide for a lot of atomic and solid state physical experiments

Parallels plane projection and its geometric features

A new equivalent map projection called the parallels plane projection is proposed in this paper. The transverse axis of the parallels plane projection is the expansion of the equator and its vertical axis equals half the length of the central meridian. On the parallels plane projection, meridians are projected as sine curves and parallels are a series of straight, parallel lines. No distortion of length occurs along the central meridian or on any parallels of this projection. Angular distortion and the proportion of length along meridians (except the central meridian) introduced by the projection transformation increase with increasing longitude and latitude. A potential application of the parallels plane projection is that it can provide an efficient projection transformation for global discrete grid systems.

Adhesive strength of new thermal barrier coatings of rare earth zirconates

La2Zr2O7 (LZ) and La-2(Zr0.7Ce0.3)(2)O-7 (LZ7C3) as novel candidate materials for thermal barrier coatings (TBCs) were prepared by electron beam-physical vapor deposition (EB-PVD). The adhesive strength of the as-deposited LZ and LZ7C3 coatings were evaluated by transverse scratch test. Meanwhile, the factors affecting the critical load value were also investigated. The critical load value of LZ7C3 coating is larger than that of LZ coating, whereas both values of these two coatings are lower than that of the traditional coating material, i.e. 8 wt% yttria stabilized zirconia (8YSZ). The micro-cracks formed in the scratch channel can partially release the stress in the coating and then enhance the adhesive strength of the coating. The width of the scratch channel and the surface spallation after transverse scratch test are effective factors to evaluate the adhesive strength of LZ and LZ7C3 coatings.

TEM studies on single crystal structure of syndiotactic poly(propene-co-butene-1)s

Themorphologies and structures of single crystals of syndiotactic poly(propene-co-1-butene) (PPBU) with 1-butene contents of 2.6, 4.2, 9.9, 16.2, and 47.9 mol % are studied by transmission electron microscopy and electron diffraction. The electron diffraction results show that the 1-butene units are included in the crystalline phase of the sPP homopolymer. A small amount of 1-butene (<4.2 mol %) has no significant influence on the antichiral chain packing of sPP. With increasing content of 1-butene units, an increasing packing disorder is observed in the PPBU copolymers. The antichiral packing model is, however, always the predominant chain packing structure of the copolymers with the analyzed composition. Bright-field electron microscopy observation shows that the PPBU single crystals exhibit always regular rectangular or lathlike shapes with preferred growth direction along their crystallographic b-axes owing to their packing features. The incorporated 1-butene units influence the crystallization behavior of sPP distinctly. With the increase of the 1-butene units, the aspect ratio of the single crystals increases. Furthermore, the typical transverse microcracks and ripples of the highly stereoregular sPP are no more so prominent for the copolymers. The microcracks are occasionally observed in the single crystals of copolymers with low 1-butene content (less than or equal to4.2 mol %), while transverse ripples are only seen in the crystals of the copolymer having a 1-butene content of 9.9 mol %. With a further increase in the content of 1-butene units, the copolymers behave like the low stereoregular sPP, where neither cracks nor ripples are observed any more.

Nanostructure and mechanical measurement of highly oriented lamellae of melt-drawn HDPE by scanning probe microscopy

Scanning probe microscopy was used to simultaneously determine the molecular chain structure and intrinsic mechanical properties, including anisotropic elastic modulus and friction, for lamellae of highly oriented high-density polyethylene (HDPE) obtained by the melt-drawn method. The molecular-scale image of the highly oriented lamellae by friction force microscopy (FFM) clearly shows that the molecular chains are aligned parallel to the drawing direction, and the periodicities along and perpendicular to the drawing direction are 0.26 and 0.50 nm, respectively. The results indicate that the exposed planes of the lamellae resulting from the melt-drawn method are (200), which is consistent with results of transmission electron microscopy and electron diffraction. Because of the high degree of anisotropy in the sample, coming from alignment of the molecular chains along the drawing direction, the measured friction force, F, determined by FFM is strongly dependent on the angle, theta, between the scanning direction and the chain axis. The force increases as theta is increased from 0 degrees (i.e., parallel to the chain axis) to 90 degrees (i.e., perpendicular to the chain axis). The structural anisotropy was also found to strongly influence the measurements of the transverse chain modulus of the polymer by the nanoindentation technique. The measured value of 13.8 GPa with transverse modulus was larger than the value 4.3 GPa determined by wide-angle X-ray diffraction, which we attributed to anisotropic deformation of the lamellae during nanoindentation measurements that was not accounted for by the elastic treatment we adopted from Oliver and Pharr. The present approach using scanning probe microscopy has the advantage that direct correlations between the nanostructure, nanotribology, and nanomechanical properties of oriented samples can be determined simultaneously and simply.

Morphology and structure of poly(aryl ether ketone ketone) containing isophthaloyl moieties crystallized from dilute solution

Spherulites and lamellar single crystals of poly(aryl ether ketone ketone) containing isophthaloyl moieties (PEKK(I)) were obtained from dilute alpha-chloronaphthalene solution. The morphology and structure of the spherulites and single crystals were studied by electron microscopy and electron diffraction. The spherulites were found to consist of elongated lamellar branches that grow with the b crystallographic axis in the radial direction. Single crystals possess a similar habit, with b parallel to the long axis, a transverse, and c perpendicular to the lamellae plane. High-resolution images of the PEKK(I) crystals which show the perfection of and defects in the crystals, were obtained, and many defects or dislocations a,ere observed. (C) 1997 Elsevier Science Ltd.

Study on the microstructure and properties of nanosized stannic oxide powders

Stannic oxide xerogel was prepared by a forced hydrolysis method using SnCl4 as the precursor. The average grain sizes of the nanosized stannic oxide powders varied with the sintering temperatures. The powders were characterized by several different physico-chemical techniques. TEM was employed for the direct observation on grain sizes, shape and state of aggregation of the particles. XRD technique was used for the determination of the crystalline structure. Microstructural parameters of average crystallite size () and mean-square root microstrain (epsilon(2)>(1/2)) for the samples were calculated from the broadened values of the half-peak intensity of XRD. The atomic ratio between oxygen and tin in the surface region of the particles was estimated through the analysis of XPS. Attributing to lots of oxygen vacancies in the surface region of the nanoparticulates and the 'trapped electrons' in the vacancies, an ESR signal was observed in the sample sintered at 300 degrees C for 2 h. FTIR of the powders showed that intensity of the transverse optical mode of Sn-O stretching vibration increased with the sintering temperature while the bending vibration of O-Sn-O showed a blue shift. For Raman spectra, very important spectral characteristics such as variations of intensity and width of the bands were observed. A new Raman vibrational band located at 572 cm(-1) was identified in the samples of nanosized stannic oxide powders. Variation of these spectroscopic properties were strongly affected by grain size, shape and state of aggregation of the nanosized particulates.

Surface roughness characterization of soft x-ray multilayer films on the nanometer scale

The soft x-ray reflectivity of multilayer films is affected by the surface roughness on the transverse nanometer scale. Scanning tunneling microscopy (STM) is an ideal instrument for providing high-lateral-resolution roughness measurements for soft x-ray multilayer films that cannot be obtained with other types of instruments on the transverse nanometer scale. The surface roughnesses of Mo/Si, Mo/C, and W/Si soft x-ray multilayer films prepared by an ion-beam-sputtering technique were measured with a STM on the vertical and transverse attributes. The film roughnesses and average spatial wavelengths added to the substrates depend on the multilayer film fabrication conditions, i.e., material combinations, number of layers, and individual layer thickness. These were estimated to lead to a loss of specular reflectivity and variations of the soft x-ray scattering angle distribution. This method points the way to further studies of soft x-ray multilayer film functional properties and can be used as basic guidance for selecting the best coating conditions in the fabrications of soft x-ray multilayer films. (C) 1996 American Vacuum Society.

Breaking seasonal limitation: year-round sporogenesis in the brown alga Laminaria saccharina by blocking the transport of putative sporulation inhibitors

Year-round induction of sporogenesis of Laminaria saccharina was performed by mechanically blocking the transport of the putative sporulation inhibitors produced by the blade meristem and culturing the plants in constant short days. Sporogenesis was successfully induced by removal of the blade meristem, either by cultivating distal blade fragments or by performing a transverse cut in the frond. The earliest sorus formation after artificial induction was 10 days. The age of the sporophytes used for induction was 6-11 months or 2 years in tank-grown or field-collected sporophytes, respectively. Zoospores were successfully released in all cases. Thus, by year-round artificial induction of sporogenesis, (1) sporeling production of L. saccharina and thereafter sporophyte cultivation could be achieved without seasonal limitation, and (2) the life cycle of L. saccharina (from spore to spore) could be completed within 8 months under controlled conditions. (C) 2004 Elsevier B.V. All rights reserved.

Morphological and phylogenetic analysis of a Gymnodinium-like species from the Chinese Coast

A Gymnodinium-like species was studied with light microscopy (LM) and scanning electron microscopy (SEM). Also, the internal transcribed spacers (containing 5.8S rDNA) and large ribosomal subunit DNA (D1-D2) sequences were obtained by PCR amplification, and then sequenced to explore the relationships within our isolate, Gymnodinium and other Gymnodinium-like species, including Karenia, Gyrodinium, Karlodinium and Symbiodinium. The LM observation showed that the species was characterized by moving in a levorotatory direction, visible hypocone, epicone and transverse groove, all of which are typical for Gymnodinium. In addition, two flagella could be found under SEM. The phylogenetic analysis revealed that the isolate grouped with Symbiodium, rather than other relevant dinoflagellates. All results showed our isolate belongs to Symbiodium. The strain was isolated from a red tide water sample, denoting that Symbiodium may be causative species for algal bloom.

Seismic profiles across the middle Tan-Lu fault zone in Laizhou Bay, Bohai Sea, eastern China

The stratigraphic architecture, structure and Cenozoic tectonic evolution of the Tan-Lu fault zone in Laizhou Bay, eastern China, are analyzed based on interpretations of 31 new 2D seismic lines across Laizhou Bay. Cenozoic strata in the study area are divided into two layers separated by a prominent and widespread unconformity. The upper sedimentary layer is made up of Neogene and Quaternary fluvial and marine sediments, while the lower layer consists of Paleogene lacustrine and fluvial facies. In terms of tectonics, the sediments beneath the unconformity can be divided into four main structural units: the west depression, central uplift, east depression and Ludong uplift. The two branches of the middle Tan-Lu fault zone differ in their geometry and offset: the east branch fault is a steeply dipping S-shaped strike-slip fault that cuts acoustic basement at depths greater than 8 km, whereas the west branch fault is a relatively shallow normal fault. The Tan-Lu fault zone is the key fault in the study area, having controlled its Cenozoic evolution. Based on balanced cross-sections constructed along transverse seismic line 99.8 and longitudinal seismic line 699.0, the Cenozoic evolution of the middle Tan-Lu fault zone is divided into three stages: Paleocene-Eocene transtension, Oligocene-Early Miocene transpression and Middle Miocene to present-day stable subsidence. The reasons for the contrasting tectonic features of the two branch faults and the timing of the change from transtension to transpression are discussed. Crown Copyright (C) 2008 Published by Elsevier Ltd. All rights reserved.

Ship-board measurements and estimations of air-sea fluxes in the western tropical Pacific during TOGA COARE

Direct air-sea flux measurements were made on RN Kexue #1 at 40 degrees S, 156 degrees E during the Tropical Ocean Global Atmosphere (TOGA) Coupled Ocean-Atmospheric Response Experiment (COARE) Intensive Observation Period (IOP). An array of six accelerometers was used to measure the motion of the anchored ship, and a sonic anemometer and Lyman-alpha hygrometer were used to measure the turbulent wind vector and specific humidity. The contamination of the turbulent wind components by ship motion was largely removed by an improvement of a procedure due to Shao based on the acceleration signals. The scheme of the wind correction for ship motion is briefly outlined. Results are presented from data for the best wind direction relative to the ship to minimize flow distortion effects. Both the time series and the power spectra of the sonic-measured wind components show swell-induced ship motion contamination, which is largely removed by the accelerometer correction scheme, There was less contamination in the longitudinal wind component than in the vertical and transverse components. The spectral characteristics of the surface-layer turbulence properties are compared with those from previous land and ocean results, Momentum and latent heat fluxes were calculated by eddy correlation and compared to those estimated by the inertial dissipation method and the TOGA COARE bulk formula. The estimations of wind stress determined by eddy correlation are smaller than those from the TOGA COARE bulk formula, especially for higher wind speeds, while those from the bulk formula and inertial dissipation technique are generally in agreement. The estimations of latent heal flux from the three different methods are in reasonable agreement. The effect of the correction for ship motion on latent heat fluxes is not as large as on momentum fluxes.

Mixed-layer water oscillations in tropical Pacific for ENSO cycle

The main modes of interannal variabilities of thermocline and sea surface wind stress in the tropical Pacific and their interactions are investigated, which show the following results. (1) The thermocline anomalies in the tropical Pacific have a zonal dipole pattern with 160 W as its axis and a meridional seesaw pattern with 6-8 degrees N as its transverse axis. The meridional oscillation has a phase lag of about 90 to the zonal oscillation, both oscillations get together to form the El Nino/La Nina cycle, which behaves as a mixed layer water oscillates anticlockwise within the tropical Pacific basin between equator and 12 degrees N. (2) There are two main patterns of wind stress anomalies in the tropical Pacific, of which the first component caused by trade wind anomaly is characterized by the zonal wind stress anomalies and its corresponding divergences field in the equatorial Pacific, and the abnormal cross- equatorial flow wind stress and its corresponding divergence field, which has a sign opposite to that of the equatorial region, in the off-equator of the tropical North Pacific, and the second component represents the wind stress anomalies and corresponding divergences caused by the ITCZ anomaly. (3) The trade winds anomaly plays a decisive role in the strength and phase transition of the ENSO cycle, which results in the sea level tilting, provides an initial potential energy to the mixed layer water oscillation, and causes the opposite thermocline displacement between the west side and east side of the equator and also between the equator and 12 degrees N of the North Pacific basin, therefore determines the amplitude and route for ENSO cycle. The ITCZ anomaly has some effects on the phase transition. (4) The thermal anomaly of the tropical western Pacific causes the wind stress anomaly and extends eastward along the equator accompanied with the mixed layer water oscillation in the equatorial Pacific, which causes the trade winds anomaly and produces the anomalous wind stress and the corresponding divergence in favor to conduce the oscillation, which in turn intensifies the oscillation. The coupled system of ocean-atmosphere interactions and the inertia gravity of the mixed layer water oscillation provide together a phase-switching mechanism and interannual memory for the ENSO cycle. In conclusion, the ENSO cycle essentially is an inertial oscillation of the mixed layer water induced by both the trade winds anomaly and the coupled ocean-atmosphere interaction in the tropical Pacific basin between the equator and 12 degrees N. When the force produced by the coupled ocean-atmosphere interaction is larger than or equal to the resistance caused by the mixed layer water oscillation, the oscillation will be stronger or maintain as it is, while when the force is less than the resistance, the oscillation will be weaker, even break.