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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

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

‘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

‘Whole-molecule Disorder’ Refinement of 4-Tricyanovinyl-N,N-diethylaniline

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Chinese Journal of Structural Chemistry 2011年第9期30卷 1286-1288页

作者： ng Seik Weng Department of Chemistry University of Malaya Chemistry Department Faculty of Science King Abdulaziz University

The molecule of 4-tricyanovinyl-N,N-diethylaniline is disordered about an axis that is close to the axis passing through the 1,4-carbon atoms. The disorder is a 1：1 type of disorder that involves only part of the molecule as the diethylamino substitutent and the three nitrogen atoms of the tricyanovinyl substituent are ordered. The treatment of the nearly ‘whole-molecule disorder’ by employing a small number of restraints is described. Crystal data： C15H14N4, triclinic, P , a = 7.1996（5）, b = 7.7232（5）, c = 12.4171（8） , α = 99.350（1）, β = 94.647（1）, γ = 103.312（1）o and V = 657.90（8） 3 at –173 K.

关键词： whole-molecule disorder

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

The roles of black phosphorus in performance enhancement of halide perovskite solar cells

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Journal of Energy Chemistry 2022年第4期31卷 672-683页

作者： Damir Aidarkhanov Charles Surya Annie ng Department of Electrical and Computer Engineering School of Engineering and Digital SciencesNazarbayev UniversityKabanbay Batyr Ave.53Nur-Sultan 010000Kazakhstan Innovation and Technology Commission Central Government Offices2 Tin Mei AvenueHong Kong 999077China

Hybrid organic-inorganic perovskite solar cells(PSCs) are considered to be the most promising thirdgeneration photovoltaic(PV) technology with the most rapid rate of increase in the power conversion efficiency(PCE). To date, their PCE values are comparable to the established photovoltaic technologies such as crystalline silicon. Intensive research activities associated with PSCs have been being performed,since 2009, aiming to further boost the device performance in terms of efficiency and stability via different strategies in order to accelerate the progress of commercialization. The emerging 2 D black phosphorus(BP) is a novel class of semiconducting material owing to its unique characteristics, allowing them to become attractive materials for applications in a variety of optical and electronic devices, which have been comprehensively reviewed in the literature. However, comprehensive reviews focusing on the application of BP in PSCs are scarce in the community. This review discusses the research works with the incorporation of BP as a functional material in PSCs. The methodology as well as the effects of employing BP in different regions of PSCs are summarized. Further challenges and potential research directions are also highlighted.

关键词： Perovskite solar cells Black phosphorus Power conversion efficiency Stability Low dimensional materials

NUMERICAL STUDIES OF A CLASS OF COMPOSITE PRECONDITIONERS

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Journal of Computational Mathematics 2014年第2期32卷 136-151页

作者： Qiang Niu Michael ng Mathematics and Physics Centre Xi'an Jiaotong-Liverpool University Suzhou 215123 China Department of Mathematics Hong Kong Baptist University Kowloon Tong Hong Kong

In this paper, we study a composite preconditioner that combines the modified tangential frequency filtering decomposition with the ILU（O） factorization. Spectral property of the composite preconditioner is examined by the approach of Fourier analysis. We illustrate that condition number of the preconditioned matrix by the composite preconditioner is asymptotically bounded by O（hp -2/3） on a standard model problem. Performance of the composite preconditioner is compared with other preconditioners on several problems arising from the discretization of PDEs with discontinuous coefficients. Numerical results show that performance of the proposed composite preconditioner is superior to other relative preconditioners.

关键词： Preconditioner ILU Tangential frequency filtering decomposition GMRES.

Lowered testosterone in male obesity： mechanisms, morbidity and management

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Asian Journal of Andrology 2014年第2期16卷 223-231,I0008页

作者： Mark ng Tang Fui Department of Medicine Austin Health University of Melbourne Melbourne Department of Endocrinology Austin Health Melbourne Victoria Australia

With increasing modernization and urbanization of Asia, much of the future focus of the obesity epidemic will be in the Asian region. Low testosterone levels are frequently encountered in obese men who do not otherwise have a recognizable hypothalamic-pituitary-testicular （HPT） axis pathology. Moderate obesity predominantly decreases total testosterone due to insulin resistance-associated reductions in sex hormone binding globulin. More severe obesity is additionally associated with reductions in free testosterone levels due to suppression of the HPT axis. Low testosterone by itself leads to increasing adiposity, creating a self-perpetuating cycle of metabolic complications. Obesity-associated hypotestosteronemia is a functional, non-permanent state, which can be reversible, but this requires substantial weight loss. While testosterone treatment can lead to moderate reductions in fat mass, obesity by itself, in the absence of symptomatic androgen deficiency, is not an established indication for testosterone therapy. Testosterone therapy may lead to a worsening of untreated sleep apnea and compromise fertility. Whether testosterone therapy augments diet- and exercise-induced weight loss requires evaluation in adequately designed randomized controlled clinical trials.

关键词： androgens hypogonadism obesity testosterone weight loss

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微生物自修复混凝土的制备及性能研究

价值工程 2024年第10期43卷 74-76页

作者：李茜茜刘昭洋赵明敏 Serina ng 王进春石家庄市长安育才建材有限公司石家庄051430 石家庄市建筑功能材料产业技术研究院石家庄051430 四川砼道科技有限公司成都610200

通过嗜碱芽孢杆菌胶与匹配的胶结液制备微生物修复剂,并自主研发疏水剂,通过向混凝土中加入疏水剂,改变了混凝土颗粒结构、降低土微粒界面活性,使之可以更好地配合微生物胶结对混凝土的固化,固化后的混凝土韧性大大提升,避免混凝土发生... 详细信息

通过嗜碱芽孢杆菌胶与匹配的胶结液制备微生物修复剂,并自主研发疏水剂,通过向混凝土中加入疏水剂,改变了混凝土颗粒结构、降低土微粒界面活性,使之可以更好地配合微生物胶结对混凝土的固化,固化后的混凝土韧性大大提升,避免混凝土发生破坏后强度瞬间丧失的情况发生。并通过大蒜素水溶液,在后期加强微生物对混凝土的加工作用,实现混凝土的“自愈合”效果。

关键词：微生物自修复疏水剂混凝土裂缝