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Stretch-Minimizing Volumetric Parameterization

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Journal of Computer Science & Technology 2015年第3期30卷 553-564页

作者：金耀钱归平赵杰伊常建童若锋张建军 Department of Computer Science and Engineering Zhejiang University Hangzhou 310027 China College of New media Zhejiang University of Media and Communications Hangzhou 310018 China National centre for Computer Animation Bournemouth University Bournemouth BH12 5BB U.K.

Not many methods for parameterization guarantee bijectivity or local injectivity, which is essential for foldover- free mappings. Stretch-minimizing parameterization which is widely used for surface parameterization, provides foldover-free mappings and is capable of trading off between angle and area distortions. We extend its usage to volumetric parameterization in this paper by deriving a 3D version of stretch-distortion energy and incorporating fixed boundary conditions. Our energy definition includes a naturM barrier term which effectively prevents elements from collapsing and folding over. It saves the effort in other methods of formulating additional energy or constrains to ensure the local injectivity. We propose to minimize the overall energy integrated over the whole mesh with a relaxation-enhanced solver and optimize the energy globally. This is different from the conventional approach of surface parameterization where mesh nodes are optimized individually. Compared with other volumetric parameterizations, method, being foldover-free and offering a good trade-off between our approach bears the advantages of stretch-minimizing angle and volume distortions.

关键词： stretch-minimizing volumetric parameterization foldover-free

In situ electron holography of the dynamic magnetic field emanating from a hard-disk drive writer

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Nano Research 2015年第4期8卷 1241-1249页

作者： Joshua F. Einsle Christophe Gatel Aurelien Masseboeuf Robin Cours Muhammad A. Bashir Mark Gubbins Robert M. Bowman Etienne Snoeck centre for nanostructured media School of Mathematics and Physics Queen's University Belfast Belfast BT7 1NN UK CEMES-CNRS 29 rueJ. Marvig 31055 Toulouse France Universite de Toulouse Paul Sabatier 118 route de Narbonne 31062 Toulouse Cedex 9 France Seagate Technology I Disc Drive Springtown Industrial Estate Derry City Co. BT48 OBF Londonderry UK

The proliferation of mobile devices in society accessing data via the ＂cloud＂ is imposing a dramatic increase in the amount of information to be stored on hard disk drives （HDD） used in servers. Forecasts are that areal densities will need to increase by as much as 35% compound per annum and by 2,020 cloud storage capacity will be around 7 zettabytes corresponding to areal densities of 2 Tb/in^2. This requires increased performance from the magnetic pole of the electromag- netic writer in the read/write head in the HDD. Current state-of-art writing is undertaken by morphologically complex magnetic pole of sub 100 nm dimensions, in an environment of engineered magnetic shields and it needs to deliver strong directional magnetic field to areas on the recording media around 50 nm × 13 nm. This points to the need for a method to perform direct quantitative measurements of the magnetic field generated by the write pole at the nanometer scale. Here we report on the complete in situ quantitative mapping of the magnetic field generated by a functioning write pole in operation using electron holography. The results point the way towards a new nanoscale magnetic field source to further develop in situ transmission electron microscopy.

关键词： electron transmissionmicroscopy off-axis electronholography in situ magnetic field magnetic recording hard disk write pole

Bibliometric analysis of micro-nano manufacturing technologies

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Nanotechnology and Precision Engineering 2019年第2期2卷 61-70页

作者： Maryna Bodnariuk Ruslan Melentiev Department of Information Activity and media Communications Odessa National Polytechnic UniversityOdessaUkraine centre of Micro/Nano Manufacturing Technology(MNMT-Dublin) University College DublinDublinIreland

Manufacturing is the primary industry promoting economic and social *** the past 30 years,the global trends of preciseness and device miniaturisation have promoted manufacturing to the micro(μ)and nano(η)*** of themost promising micro-nano manufacturing technologies(MNMT)is of interest to industry,academia and private and national science investing *** the exponential broadening of the research area and an enormous volume of literature,providing an overview of the state of the art is far beyond the scope of a technical review *** study performs bibliometric analysis of a stream of academic literature devoted toμ-andη-*** goals of the analysis are to assess the current core and trends in the field *** and citation statistics from 1988 were collected from theWeb of Science,Google Scholar,Scopus,Engineering Village,ScienceDirect and SpringerLink databases and were then analysed and illustrated with Microsoft Excel and VOSviewer *** top keywords,articles,journals,authors,universities and countrieswere identified according to different *** index of normalised influence was offered to evaluate the top element in each *** observed that the most powerful keywords were present in well-known articles published in prominent journals by authoritative scientists at leading universities in the countries that are most actively engaged in *** implications of the research outcomes for investors and academicians are summarised in the conclusion.

关键词： Bibliometric analysis Micro-machining Nano-machining Top Citations

Understanding the catalysis of chromium trioxide added magnesium hydride for hydrogen storage and Li ion battery applications

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Journal of Magnesium and Alloys 2024年第3期12卷 1117-1130页

作者： D.Pukazhselvan IhsanÇaha Catarina de Lemos Sergey M.Mikhalev Francis Leonard Deepak Duncan Paul Fagg Department of Mechanical Engineering TEMA-Centre for Mechanical Technology and AutomationUniversity of AveiroAveiro 3810-193Portugal LASI-Intelligent Systems Associate Laboratory Guimarães 4800-058Portugal nanostructured Materials Group International Iberian Nanotechnology Laboratory(INL)Avenida Mestre Jose VeigaBraga 4715-330Portugal

This study explores how the chemical interaction between magnesium hydride(MgH_(2))and the additive CrO_(3) influences the hydrogen/lithium storage characteristics of MgH_(2).We have observed that a 5 wt.%CrO_(3) additive reduces the dehydrogenation activation energy of MgH_(2) by 68 kJ/mol and lowers the required dehydrogenation temperature by 80℃.CrO_(3) added MgH_(2) was also tested as an anode in an Li ion battery,and it is possible to deliver over 90%of the total theoretical capacity(2038 mAh/g).Evidence for improved reversibility in the battery reaction is found only after the incorporation of additives with MgH_(2).In depth characterization study by X-ray diffraction(XRD)technique provides convincing evidence that the CrO_(3) additive interacts with MgH_(2) and produces Cr/MgO *** free energy analyses confirm the thermodynamic feasibility of conversion from MgH_(2)/CrO_(3) to MgO/Cr,which is well supported by the identification of Cr(0)in the powder by X ray photoelectron spectroscopy(XPS)*** high resolution transmission electron microscopy(HRTEM)and energy dispersive spectroscopy(EDS)we found evidence for the presence of 5 nm size Cr nanocrystals on the surface of MgO rock salt *** is also convincing ground to consider that MgO rock salt accommodates Cr in the *** observations support the argument that creation of active metal–metal dissolved rock salt oxide interface may be vital for improving the reactivity of MgH_(2),both for the improved storage of hydrogen and lithium.

关键词： Hydrogen storage Rechargeable batteries Binary hydrides Metal oxides Catalytic mechanism.

China's new strategy for fighting misconduct in academic journals

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Chinese Medical Journal 2019年第15期132卷 1865-1866页

作者： Jian-Ping Lu Research centre for Quality of Foreign Language media College of Media and International Culture Zhejiang University Hangzhou Zhejiang 310007 China

The Central Committee of the Communist Party of China issued its first policy related to academic ethics on May 30th,2018,together with the State Council.[1] It introduced in detail a raft of reforms aiming at the improvement of academic integrity across the research spectrum covering funding,job applications,peer-review,and *** new policy clarified that a high-level management system for scientific research integrity with clear responsibilities and efficient coordination should be established,requiring that the Ministry of Science and Technology (MOST) and the Chinese Academy of Social Sciences (CASS) be responsible for the overall coordination and guidance of scientific research integrity in the fields of natural sciences,philosophy,and social sciences.

关键词： strategy misconduct in academic journals

Conducting Polyaniline-Electrical Charge Transportation

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Materials Sciences and Applications 2013年第1期4卷 1-10页

作者： Veluru J. Babu Sesha Vempati Seeram Ramakrishna Center for Nanofibers & Nanotechnology Nanoscience and Nanotechnology Initiative National University of Singapore Singapore Center for nanostructured media School of Mathematics and Physics Queen’s University of Belfast UK

Conductive polyanilines are synthesized by doping with inorganic and organic acids, namely Hydrochloric acid (HCl) and ±10-camphor sulfonic acid (CSA). The direct current (DC) conductivities (σDC) are found to be about 9.5 ′ 10-8, 1.8, and 95.8 S/cm for PANI base, PANI(HCl) and PANI(CSA), respectively. σDC is measured down to a temperature of ~100 K and the apparent change in the activation energies are found to be 98.16, 74.40, and 57.24 meV for PANI base, HCl, and CSA dopings respectively. σDC is less temperature dependent near room temperature, further decrease in temperature the σDC is strongly dependent. Upon the inspection of AC conductivities (σAC) versus frequency curves, it can be inferred that the conduction process is noticeably influenced upon doping and within the dopants. σAC has shown classical plateau (DC-AC crossover) region, nonetheless shifted crossover frequency (critical frequency) upon doping is rather interesting. Critical frequencies (wc) are obtained from universal power-law for all samples. The variation in the dielectric properties can be attributed to the dopant incorporation. In material characterization, successful doping is corroborated by FTIR, UV-vis spectroscopy and slight influence upon doping can also be seen in thermal properties. Intense photoluminescence (PL) peaks at 322.5, 581.4 and 644.2 nm are observed. PANI(CSA) exhibited highest peak intensity followed by PANI(HCl) and PANI base.

关键词： Protonation Composites Electrical Transportation AC Conductivity

Nuclear Properties of Carbon Nanotubes for Fast Neutron Detection

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Journal of Energy and Power Engineering 2018年第4期12卷 192-196页

作者： Jorge Antonio Garcia Gallardo Sebastián Beneitez Pupo Mauricio Petaccia Juana Gervasoni Department of Metallic and nanostructured Materials（MMyN） Bariloche Atomic Centre（CNEA）San Carlos de Bariloche 8400Argentin

Fast neutron detection is a subject of great relevance in modem nuclear science and engineering, in particular, with the recent advances in nuclear fusion research, detection of fast neutron became a key issue. Nuclear properties of carbon are of special interest due to its relatively high capture cross section for fast neutrons. Devices made of silicon carbide and diamond are based on these properties, and so are being developed to be used with the proper wiring. In addition, in recent years carbon nano-tubes unveiled their electrical and mechamical properties, which can be exploited for neutron detection. In this work, we use MCNP5 Monte Carlo code to analyze the carbon nuclear properties and discuss the way nano-tubes can be used for fast neutron detection.

关键词： Fast neutron nuclear fusion carbon nano-tube nano-device.

Shuffling the cards in signal transduction: Calcium, arachidonic acid and mechanosensitivity

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World Journal of Biological Chemistry 2011年第4期2卷 59-66页

作者： Luca Munaron Department of Animal and Human Biology Nanostructured Interfaces and Surfaces Centre of Excellence Center for Complex Systems in Molecular Biology and Medicine University of Torino

Cell signaling is a very complex network of biochemical reactions triggered by a huge number of stimuli coming from the external medium. The function of any single signaling component depends not only on its own structure but also on its connections with other biomolecules. During prokaryotic-eukaryotic transition, the rearrangement of cell organization in terms of diffusional compartmentalization exerts a deep change in cell signaling functional potentiality. In this review I briefly introduce an intriguing ancient relationship between pathways involved in cell responses to chemical agonists (growth factors, nutrients, hormones) as well as to mechanical forces (stretch, osmotic changes). Some biomolecules (ion channels and enzymes) act as "hubs", thanks to their ability to be directly or indirectly chemically/mechanically co-regulated. In particular calcium signaling machinery and arachidonic acid metabolism are very ancient networks, already present before eukaryotic appearance. A number of molecular "hubs", including phospholipase A2 and some calcium channels, appear tightly interconnected in a cross regulation leading to the cellular response to chemical and mechanical stimulations.

关键词： Arachidonic acid Calcium signaling Evolution Mechanosensitivity Phospholipase A2

Visible-light-induced direct 3-ethoxycarbonyl- methylation of 2-aryl-2H-indazoles in water

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Organic Chemistry Frontiers 2022年第5期9卷 1445-1450页

作者： Chun-Hua Ma Lu Zhao Xing He Yu-Qin Jiang Bing Yu Collaborative Innovation centre of Henan Province for Green Manufacturing of Fine Chemicals Key Laboratory of Green Chemical Media and ReactionsMinistry of EducationHenan Engineering Research Centre of Chiral Hydroxyl PharmaceuticalHenan Engineering Laboratory of Chemical Pharmaceutical and Biomedical MaterialsSchool of Chemistry and Chemical EngineeringHenan Normal UniversityXinxiang 453007China Green Catalysis centre College of ChemistryZhengzhou UniversityZhengzhou 450001China

A visible-light-driven rhodamine B-catalyzed transition-metal-free 3-ethoxycarbonylmethylation of 2-aryl-2H-indazoles and imidazo[1,2-a]pyridines(40 examples)using commercially availableα-bromoesters was realized in *** protocol features sustainability,operational simplicity,mild reaction conditions,and remarkable substrate ***,α-bromoamides are also appropriate substrates for affording 3-carbamylmethylation *** could be used for the synthesis of the drug zolpidem and the late-stage modification of natural products.

关键词： carbonyl light simplicity