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Indexing Non-merohedrally Twinned Crystals by Bruker'sAPEX2 and Agilent's CrysAlis^(PRO), an Example of a Crystal Structure That Can Be Refined through Either the PLATONRoute or the ‘HKLF 5' Route, and, Simultaneous Data Collection of Two Crystals in a Two-in-one Run

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Chinese Journal of Structural Chemistry 2014年第2期33卷 294-303页

作者： ng Seik Weng Department of Chemistry University of Malaya 50603 Kuala Lumpur Malaysia Chemistry Department King Abdulaziz University

The first part of this report describes the data reduction of non-merohedrally twinned crystals measured on Bruker and Agilent area-detector diffractometers. The image frames of methyl-2-aminopyrazine-3-carboxylate were processed with APEX2 to furnish a set of overlapping diffraction indices that were used for solution and refinement. CrysAlisPRO was used for processing the frames of bis（diethyldicarbamato）nickel, which exists in monoclinic and tetragonal polymorphs, and in untwinned and twinned forms. In the second part, the crystal structure of [（3-formyl-4- hydroxyphenyl）methyl]triphenylphosphanium chloride was refined through the ‘HKLF 5＇（based on a combined set of diffraction indices） and PLATON（based on one set of diffraction indices） routes to give identical outcomes because the amount of overlap of the twin domains is small. For the third part, in a proof-of-concept investigation, the diffraction pattern of untwinned and twinned 4-{（E）-（4-aminophenyl）diazenyl]phenylamine was recorded simultaneously in one run; the three domains could be indexed and the crystal structure satisfactorily refined. The refinement was identical to those derived from independent measurements; the crystal structure features two independent centrosymmetric molecules, one of which is ordered and the other whole-molecule-disordered. This two-in-one run opens up the possibility that two or more crystals having different atomic compositions can be measured simultaneously if their reciprocal lattices do not overlap significantly.

关键词： merohedral non-merohedral twin APEX2 Crys Alis^PRO two-in-one data collection

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A Nonstandard Lévy-Khintchine Formula and Lévy Processes

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Acta Mathematica Sinica,English Series 2008年第2期24卷 241-252页

作者： Siu Ah ng School of Mathematical Sciences University of KwaZulu-Natal Pietermaritzburg 3209 South Africa

We use methods from nonstandard analysis to obtain a short and simple derivation of the Levy-Khintchine formula via an explicit construction of certain laws of the infinitesimal increments. Consequently, any arbitrary... 详细信息

关键词： Levy processes Levy-Khintchine formula nonstandard analysis infinitesimal hyperfinite

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马来西亚东北部Setiu潟湖1970年以来沉积环境演化及其对ENSO的响应

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海洋学报 2024年第4期46卷 79-89页

作者：赵周平李超骆正骅 Nicholasng Chia Wei 戴璐同济大学海洋地质国家重点实验室上海200092

马来半岛位于低纬热带地区,厄尔尼诺-南方涛动(El Nino-Southern Oscillation,ENSO)如何影响该区域的气候,尤其是降水仍然存在争议。本文以马来半岛东北部登嘉楼州Setiu潟湖钻孔NTT-3为研究对象,通过分析粒度、总有机碳及总氮含量、C/N... 详细信息

马来半岛位于低纬热带地区,厄尔尼诺-南方涛动(El Nino-Southern Oscillation,ENSO)如何影响该区域的气候,尤其是降水仍然存在争议。本文以马来半岛东北部登嘉楼州Setiu潟湖钻孔NTT-3为研究对象,通过分析粒度、总有机碳及总氮含量、C/N比值和XRF岩心扫描等,探讨该钻孔的沉积环境变化及其对ENSO的响应。研究结果显示,钻孔记录中自1970年前后(84 cm处)出现两种不同的变化趋势。1970年之前钻孔下部沉积物粒度、有机和无机地球化学特征趋势波动明显,沉积速率较低。而1970年以来,潟湖沉积环境总体稳定,沉积物中的有机组分主要来自红树林,同时伴有河流输入的淡水浮游植物的贡献。频谱分析结果显示1970年以来钻孔上部存在明显的ENSO周期变化。强厄尔尼诺现象基本对应低Zr/Rb比值和低Zr/Ti比值,而强拉尼娜(La Nina)现象基本对应高Zr/Rb比值和高Zr/Ti比值。该结论不仅支持了现代观测对马来半岛东部沿海地区气候变化的认识,同时也在地质记录中发现了ENSO变化的直接证据,对全面认识和理解ENSO对亚洲气候变化的影响、区域陆海相互作用过程和环境响应等方面具有重要现实意义。

关键词： Setiu潟湖沉积记录频谱分析 ENSO

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miniSCIDOM: a scintillator-based tomograph for volumetric dose reconstruction of single laser-driven proton bunches

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High Power Laser Science and Engineering 2024年第2期12卷 41-50页

作者： A.Corvino M.Reimold E.Beyreuther F.-E.Brack F.Kroll J.Pawelke J.D.Schilz M.Schneider U.Schramm M.E.P.Umlandt K.Zeil T.Ziegler J.Metzkes-ng Helmholtz-Zentrum Dresden–Rossendorf DresdenGermany Technische Universität Dresden DresdenGermany OncoRay–National Center for Radiation Research in Oncology Faculty of Medicine and University Hospital Carl Gustav CarusTUD Dresden University of TechnologyHelmholtz-Zentrum Dresden–RossendorfDresdenGermany Current affiliation:Institut Curie UniversitéPSLCNRS UMR3347OrsayFrance Current affiliation:Universitätsklinikum Freiburg FreiburgGermany

Laser plasma accelerators(LPAs)enable the generation of intense and short proton bunches on a micrometre scale,thus offering new experimental capabilities to research fields such as ultra-high dose rate radiobiology or material *** spectrally broadband,laser-accelerated proton bunches allow for tailored volumetric dose deposition in a sample via single bunches to excite or probe specific sample *** rising number of such experiments indicates a need for diagnostics providing spatially resolved characterization of dose distributions with volumes of approximately 1 cm^(3) for single proton bunches to allow for fast online *** we present the scintillator-based miniSCIDOM detector for online single-bunch tomographic reconstruction of dose distributions in volumes of up to approximately 1 cm^(3).The detector achieves a spatial resolution below 500μm and a sensitivity of 100 *** detector performance is tested at a proton therapy cyclotron and an LPA proton *** experiments’primary focus is the characterization of the scintillator’s ionization quenching behaviour.

关键词： beam monitoring detectors laser-driven proton beams scintillator-based diagnostics ultra-high dose rate

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不同年龄功能性语音障碍儿童的辅音语音错误特征研究

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听力学及言语疾病杂志 2024年第5期32卷 417-421页

作者：彭静吴民华邹密杨硕谭洁中南大学湘雅三医院康复医学科长沙410013 香港大学教育学院中国湖南中医药大学

目的研究不同年龄功能性语音障碍儿童(speech sound disorders,SSD)的语音障碍严重程度是否存在区别,并探讨其辅音语音错误特征。方法以2019年7月~2022年11月于中南大学湘雅三医院康复医学科就诊的172例SSD患儿为研究对象,其中4岁97例(... 详细信息

目的研究不同年龄功能性语音障碍儿童(speech sound disorders,SSD)的语音障碍严重程度是否存在区别,并探讨其辅音语音错误特征。方法以2019年7月~2022年11月于中南大学湘雅三医院康复医学科就诊的172例SSD患儿为研究对象,其中4岁97例(男63例,女34例),5岁45例(男36例,女9例),6岁30例(男22例,女8例)。以图片命名法对单词水平进行语音评估,记录辅音的语音错误类型,并计算辅音正确百分比(percentage consonants correct,PCC)和不同构音方式辅音(塞音化、塞擦音化、摩擦音化、鼻音化以及边音化)的错误比例。结果①三组间PCC差异无统计学意义(P>0.05);②三组间省略错误存在显著差异(Z=6.531,P=0.0380.05);③三组儿童省略错误中均以边音/l/省略为主;④三组儿童均存在较多的塞音化、塞擦音化和摩擦音化,但三组不同构音方式(塞音化、鼻音化、塞擦音化、摩擦音化和边音化)的辅音错误占比无差异(P>0.05)。结论不同年龄SSD儿童的语音障碍严重程度无明显差别,但省略错误分布存在明显差异,构音方式存在相似的语音错误特征。

关键词：功能性语音障碍辅音语音错误辅音正确百分比省略错误

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WAVE INDUCED OSCILLATORY AND STEADY FLOWS IN THE ANNULUS OF A CATHETERIZED VISCOELASTIC TUBE

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Journal of Hydrodynamics 2010年第5期22卷 605-617页

作者： ng Chiu-On CHAng Yin-Yee Department of Mechanical Engineering The University of Hong Kong

A perturbation analysis based on equations of motion in Lagrangian form is presented for the oscillatory and time-mean viscous flows induced by a propagating wave of small amplitude in an annulus with a viscoelastic outer wall. Owing to the steady streaming effect, the existence of a catheter in a blood vessel brings in an additional steady pressure gradient, a correction to that predicted by the linear theory, and an additional steady shear stress, which may increase the possibility of hemolysis of red blood cells.

关键词： annulus flow steady streaming catheterized artery

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Assessment of the kinetic–frictional model for dense granular flow

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Particuology 2008年第1期6卷 50-58页

作者： Boon Ho ng Mojtaba Ghadiri Institute of Particle Science&Engineering University of LeedsLeeds LS2 9JTUK

This paper aims to quantitatively assess the application of kinetic-frictional model to simulate the motion of dry granular materials in dense condition, in particular, the annular shearing in Couette configuration. The weight of frictional stress was varied to study the contribution of the frictional stress in dense granular flows. The results show that the pure kinetic-theory-based computational fluid dynamics （CFD） model （without frictional stress） over-predicts the dominant solids motion of dense granular flow while adding frictional stress [Schaeffer, D. G. （1987）. Instability in the evolution equations describing incompressible granular flow. Journal of Differential Equations, 66（1）, 19-50] with the solids pressure of [Lun, C. NTK., Savage, S. B., Jeffrey, D. J., ＆ Chepurniy, N. （1984）. Kinetic theories for granular flow： Inelastic particles in Couette flow and slightly inelastic particles in a general flow field. Journal of Fluid Mechanics, 140, 223-256] in the CFD model improves the simulation to better conform available experimental results. The results also suggest that frictional stress transmission plays an important role in dense granular flow and should not be neglected in granular flow simulations. Compatible simulation results to the experimental data are seen by increasing the weight of frictional stress to a factor of 1.25-1.5. These improved simulation results suggest the current constitutive relations （kinetic-frictional model） need to be improved in order to better reflect the real dense granular flow.

关键词： Gas-solids flow CFD Constitutive relations Couette flow Kinetic theory Kinetic-frictional model

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Stochastic simulation of chemical chaos

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Chinese Science Bulletin 1997年第1期42卷 47-50页

作者： Wang, HL Xin, hw UNIV SCI & TECHNOL CHINA DEPT CHEM PHYSHEFEI 230026PEOPLES R CHINA

A chemical reaction is often described by a set of ordinary differential equations based on the mass action law of chemical kinetics. From the microscopic point of view, these macroscopic rate equations originated in the microscopic elastic and reactive collision processes, and a full description of a chemical reaction includes the mean molecular numbers (or concentrations) of reacting species and the fluctuations around these mean values. In normal cases, concentra-

关键词： chaos stochastic simulation nonequilibrium.

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LASER INDUCED FLUORESCENCE DETECTOR(LIF)FOR CAPILLARY ELECTROPHORESIS

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Chinese Chemical Letters 1996年第1期7卷 39-42页

作者： Ma, MS Han, hw Liu, GQ ACAD SINICA INST CHEMBEIJING 100080PEOPLES R CHINA

A highly sensitive laser induced fluorescence detector for capillary electrophoresis is described. With an argon laser at 488 nm for excitation, the emitted light was collected by an optical fiber and measured by it PMT. Various elements that affected the sensitivity of the detector were discussed in detail. The detection limit for fluorescein was 5.4 amole.

关键词： ZONE ELECTROPHORESIS AMINO-ACIDS DERIVATIVES SEPARATION FRAGMENTS

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‘Whole-molecule Disorder’ Refinement of 4-(4-Hydroxybenzylideneiminio)phenol Hemichloride Hemihydroxide

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Chinese Journal of Structural Chemistry 2011年第9期30卷 1283-1285页

作者： ng Seik Weng Department of Chemistry University of Malaya

The two independent cations of the salt, [HO-C6H4-CH=NH-C6H4-OH]·1/2OH·1/2Cl, are both disordered about an axis connecting the two oxygen atoms at the para-positions of the aromatic rings, the disorder being in a 83：17 ratio in one cation and 91：9 in the other. The hydroxide and chloride anions are ordered. The treatment of the nearly ‘whole-molecule disorder’ by employing a small number of restraints is described. Crystal data： C13H12.5Cl0.5NO2.5, triclinic, P , a = 9.1731（4）, b = 9.2048（4）, c = 15.9144（7） , α = 104.822（1）, β = 90.077（1）, γ = 118.641（1）o and V = 1127.86（9） 3 at –173 K.

关键词： whole-molecule disorder

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