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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

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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

熔融态铁氧化物碳氢还原热力学与动力学研究现状

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钢铁研究学报 2024年第2期36卷 150-162页

作者：卢立金王锋王海风邱健平晓东钢铁研究总院有限公司先进钢铁流程及材料国家重点实验室北京100081 钢研晟华科技股份有限公司北京100081

氢能在冶金领域的应用是实现低碳发展的重要途经之一。目前虽然在富氢高炉和氢基直接还原炼铁领域取得诸多成果,但在碳氢熔融还原炼铁仍有许多不足之处。通过分析碳、CO以及氢气还原熔融态铁氧化物的研究,总结熔融还原过程基本热力学特... 详细信息

氢能在冶金领域的应用是实现低碳发展的重要途经之一。目前虽然在富氢高炉和氢基直接还原炼铁领域取得诸多成果,但在碳氢熔融还原炼铁仍有许多不足之处。通过分析碳、CO以及氢气还原熔融态铁氧化物的研究,总结熔融还原过程基本热力学特点,并对影响动力学参数的因素进行分析。结果表明,在熔融温度(1369℃)以上氢气还原FeO在热力学上有一定的优势。还原温度高于1538℃,(即还原物和还原产物都为熔融态),还原气体流量为3 mL/min以及碱度为1.1~1.3时有利于熔融反应的进行。关于碳氢还原熔融态铁氧化物的研究还不充分,还需要进一步解析还原过程、限制环节以及微观机制等。

关键词：熔融还原氢冶金热力学动力学

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

On compact splitting complex submanifolds of quotients of bounded symmetric domains

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Science China Mathematics 2017年第6期60卷 1057-1076页

作者： MOK ngaiming ng SuiChung Department of Mathematics The University of Hong Kong Department of Mathematics Shanghai Key Laboratory of PMMPEast China Normal University

We study compact complex submanifolds S of quotient manifolds X =Ω/F of irreducible bounded symmetric domains by torsion free discrete lattices of automorphisms, and we are interested in the characterization of the totally geodesic submanifolds among compact splitting complex submanifolds S C X, i.e., under the assumption that the tangent sequence over S splits holomorphically. We prove results of two types. The first type of results concerns S C X which are characteristic complex submanifolds, i.e., embedding Ω as an open subset of its compact dual manifold M by means of the Borel embedding, the non-zero （1, 0）-vectors tangent to S lift under a local inverse of the universal covering map π → X to minimal rational tangents of M. We prove that a compact characteristic complex submanifold S C X is necessarily totally geodesic whenever S is a splitting complex submanifold. Our proof generalizes the case of the characterization of totally geodesic complex submanifolds of quotients of the complex unit ball B^n obtained by Mok （2005）. The proof given here is however new and it is based on a monotonic property of curvatures of Hermitian holomorphic vector subbundles of Hermitian holomorphic vector bundles and on exploiting the splitting of the tangent sequence to identify the holomorphic tangent bundle Ts as a quotient bundle rather than as a subbundle of the restriction of the holomorphic tangent bundle Tx to S. The second type of results concerns characterization of total geodesic submanifolds among compact splitting complex submanifolds S C X deduced from the results of Aubin （1978） and Yau （1978） which imply the existence of Kahler-Einstein metrics on S C X. We prove that compact s- plitting complex submanifolds S C X of sufticiently large dimension （depending on ） are necessarily totally geodesic. The proof relies on the Hermitian-Einstein property of holomorphic vector bundles associated to TS, which implies that endomorphisms of such bundles are parallel, and the co

关键词： bounded symmetric domains tangent sequence splitting complex submanifolds varieties of minimal rational tangents K/ihler-Einstein metrics

A dual-electrolyte system for photoelectrochemical hydrogen generation using CuInS_2-In_2O_3-TiO_2 nanotube array thin film

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Science China Materials 2018年第6期61卷 895-904页

作者： Charlene ng Jung-Ho Yun Hui Ling Tan Hao Wu Rose Amal Yun Hau ng Particles and Catalysis Research Group School of Chemical Engineering The University of New South Wales

The utilization of Na2S/Na2SO3 mixture as the electrolyte solution to stabilize sulfide anode in a photoelectrochemical cell for hydrogen evolution generally compromises the current-to-hydrogen efficiency（ηcurrent） of the system. Here, the employment of a dual-electrolyte system,that is, Na2S/Na2SO3 mixture and p H-neutral Na2SO4 as the respective electrolyte solutions in the anode and cathode chambers of a water splitting cell is demonstrated to suppress the photocorrosion of CuInS2-In2O3-TiO2 nanotube（CISIn2O3-TNT） heterostructure, while simultaneously boosts theηcurrent. Although n-type CIS and In2O3 nanoparticles can be easily formed on TNT array via facile pulse-assisted electrodeposition method, conformal deposition of the nanoparticles homogeneously on the nanotubes wall with preservation of the TNT hollow structure is shown to be essential for achieving efficient charge generation and separation within the heterostructure. In comparison to Na2S/Na2SO3 solution as the sole electrolyte in both the anode and cathode chambers, introduction of dual electrolyte is shown to not only enhance the photostability of the CIS-In2O3-TNT anode, but also lead to near-unity ηcurrentas opposed to the merely 20% ηcurrentof the single-electrolyte system.

关键词： dual-electrolyte hydrogen generation photoelectrochemical TiO2 nanotubes CuInS2

AN APPROACH TO ANALYSIS OF SIngLE PIER BASED ON THE VARIATIONAL PRINCIPLE IN MULTI-LAYERED SOIL

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Acta Mechanica Solida Sinica 2001年第3期14卷 275-282页

作者： ng Shiu Cho Department of Civil Enginddring The Hong Kong University of Science and TechnologyClearwaler BayHong Kong

In this study, a variational approach to the settlement analysisof an axially loaded pier em- bedded in a multi-layered soil profileis presented. In this method, the soil profile and the embedded pierare divided into a number of sub-layers according to the actualnumber o soil layers observed in the field. The displacement shapefunction of each soil layer is given as a product of an exponentialequation along the pier depth and the Bessel's solution in the radialdirection.

关键词： pier pile settlement

Physical scientists research biomedicine: a call for caution

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Chinese Journal of Cancer Research 2015年第1期27卷 94-95页

作者： Yì-Xiáng J.Wáng Department of Imaging and Interventional Radiology Faculty of Medicine The Chinese University of Hong Kong Prince of Wales Hospital

It is noticeable that nowadays there are more and more scientists with physical science or engineering background working on or started to work on biomedical projects, but rarely vice versa. This reflects the multi-discipline nature of some projects, however, also at least partially can be explained that biomedical research is seen as trendy, fundable, and likely to get more citations and with results more publishable in high impact journals （1,2）. It is also apparent with some publications and lectures that not all these physical scientists/engineers are well-prepared to work on projects which do not align with their own expertise. Some studies are against very basic principles of pharmacology or biology, while others try to solve medical problems which do not exist clinically. I reviewed a number of submissions including a few from prestigious American universities to Nature journals which made no sense with the study design. Much of manpower and financial resource are being wasteful spent. There are also examples of clinical trials which were ill-planned right from the start and in the end only causing much inconvenience to patients to say at the least. In addition, ample examples exist where experienced physical scientists worked with inexperienced medical scientists and resulted in avoidable failures.

关键词： a call for caution very Physical scientists research biomedicine