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Episodes 2005年第4期28卷 252-256页

作者： Erwin Wolff Carreno Juan Manuel Pinzon Angel Rodolfo Contreras Moreno christoph bernardy Corporacion Autonoma Regional Para la Defensa de la Mescta de Bucaramanga Carrera 23 N°37-63 Bucaramanga Colombia Formely with Corporacidn Autonoma Regional Para la Defensa de la Mescta de Bucaramanga Carrera 23 N°37-63 Bucaramanga Colombia. Formerly with Federal Institute for Geosciences and Natural Resources Stilleweg 2 30655 Hannover Germany

Bucaramanga, with a population of about one million, is the capital of the Department of Santander (Colombia), and has the Río Suratá as its main source of drinking water. In the upper reaches of the river, small-scale gold mining has been going on for many centuries (Vetas-California mining district). Geologically, the Vetas-California mining district is part of the Santander Massif, which is composed of pre-Devonian metamorphic rocks and Mesozoic igneous rocks. The mineralisation is restricted to structurally controlled veins and is often associated with hydrothermal alteration. There is also disseminated mineralisation, but presently only the vein-type is mined. The processing residues are discharged into the nearby water-courses, contaminating the waters of the Suratá river basin. As part of a joint Colombian-German technical cooperation project, with the purpose of controlling the negative environmental effects of gold mining pollution, an integrated distillation system for the recovery of mercury has been designed and tested.

关键词：地质条件矿床哥伦比亚蒸发作用金银

ion acceleration;quantum electrodynamic effects

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High Power Laser Science and Engineering 2024年第1期12卷 60-73页

作者： Shikha Bhadoria Mattias Marklund christoph H.Keitel Max-Planck-Institut für Kernphysik HeidelbergGermany Department of Physics University of GothenburgGöteborgSweden

The impact of radiation reaction and Breit±Wheeler pair production on the acceleration of fully ionized carbon ions driven by an intense linearly polarized laser pulse has been investigated in the ultra-relativistic transparency regime.Against initial expectations, the radiation reaction and pair production at ultra-high laser intensities are found to enhance the energy gained by the ions. The electrons lose most of their transverse momentum, and the additionally produced pair plasma of Breit±Wheeler electrons and positrons co-streams in the forward direction as opposed to the existing electrons streaming at an angle above zero degree. We discuss how these observations could be explained by the changes in the phase velocity of the Buneman instability, which is known to aid ion acceleration in the breakout afterburner regime, by tapping the free energy in the relative electron and ion streams. We present evidence that these non-classical effects can further improve the highest carbon ion energies in this transparency regime.

关键词： ion acceleration quantum electrodynamic effects

Implementation and validation of a bonded particle model to predict rheological properties of viscoelastic materials

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Particuology 2024年第6期89卷 198-210页

作者： Michael Mascara Arno Mayrhofer Stefan Radl christoph Kloss Institute of Process and Particle Engineering Graz University of TechnologyInffeldgasse 13Graz8010Austria DCS Computing GmbH Industriezeile 35Linz4020Austria

This work focuses on implementing a particle-based method able to characterize viscoelastic materials whose rheological properties,such as storage modulus G′and loss modulus G″,are known.It is based on the bonded particle model,with the elastic constitutive relation here substituted with a viscoelastic one to capture time-scale effects.The Burgers model,vastly used in literature to model viscoelastic systems,is discretized and implemented.The test case used for calibration comprises of a cubic lattice,sheared with a periodic motion,to mimic the effect of a shear rheometer.After appropriate filtering of the stress response,the rheological properties are obtained,highlighting the effect of the lattice geometry,as well as the particle size,on the accuracy of the model.Moreover,the Burgers parameters are calibrated by analytically fitting the experimental dataset,showing the limitation of the Burgers model.The micro-contact parameters are obtained from the macro parameters through appropriate scaling.After completing a frequency sweep,the simulated G′and G″show a relatively large error,around 25%for G’for example.For this reason,a more robust model,namely the generalized Maxwell model,has been implemented.The calibration procedure is performed in the same fashion as for the Burgers model.Moreover,the tangential micro-contact parameters are scaled w.***.t.the normal ones.This scaling parameter,calledα,is calibrated by minimizing the root mean square error between simulation and experimental data,giving errors below 10%in both G′and G″for a large dataset.Additionally,a full ring plate-plate rheometer setup is simulated,and the simulation is compared with the given experimental dataset,again finding a good agreement.

关键词： DEM Rheology Numerical modeling Viscoelasticity

Recycled graphite for more sustainable lithium-ion batteries

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Carbon Energy 2024年第5期6卷 15-24页

作者： Mayokun Olutogun Anna Vanderbruggen christoph Frey Martin Rudolph Dominic Bresser Stefano Passerini Helmholtz Institute Ulm(HIU) Ulm Germany Karlsruhe Institute of Technology(KIT) KarlsruheGermany Helmholtz Zentrum Dresden-Rossendorf(HZDR) Helmholtz Institute Freiberg for Resource Technology(HIF)FreibergGermany ProGraphite GmbH UntergriesbachGermany Chemistry Department Sapienza University of RomeRomeItaly

The demand for lithium-ion batteries(LIBs)is driven largely by their use in electric vehicles,which is projected to increase dramatically in the future.This great success,however,urgently calls for the efficient recycling of LIBs at the end of their life.Herein,we describe a froth flotation-based process to recycle graphite—the predominant active material for the negative electrode—from spent LIBs and investigate its reuse in newly assembled LIBs.It has been found that the structure and morphology of the recycled graphite are essentially unchanged compared to pristine commercial anode-grade graphite,and despite some minor impurities from the recycling process,the recycled graphite provides a remarkable reversible specific capacity of more than 350 mAh g^(−1).Even more importantly,newly assembled graphite‖NMC532 cells show excellent cycling stability with a capacity retention of 80%after 1000 cycles,that is,comparable to the performance of reference full cells comprising pristine commercial graphite.

关键词： anode graphite lithium-ion battery recycling sustainability

Sol-gel derived B_(2)O_(3)-CaO borate bioactive glasses with hemostatic,antibacterial and pro-angiogenic activities

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Regenerative Biomaterials 2024年第1期3卷 108-118页

作者： Kai Zheng Faina Bider Mahshid Monavari Zhiyan Xu Christina Janko christoph Alexiou Ana M.Beltran Aldo R.Boccaccini Jiangsu Province Engineering Research Center of Stomatological Translational Medicine College of StomatologyNanjing Medical UniversityNanjing 210029China Jiangsu Key Laboratory of Oral Diseases Nanjing Medical UniversityNanjing 210029China Institute of Biomaterials University of Erlangen-Nuremberg91058 ErlangenGermany Department of Oto-Rhino-Laryngology Head and Neck SurgerySection of Experimental Oncology and Nanomedicine(SEON)Else Kroener-Fresenius-Stiftung ProfessorshipUniversitaetsklinikum Erlangen91058 ErlangenGermany Departamento de Ingenier�ıa y Ciencia de los Materiales y del Transporte Escuela Politecnica

Sol-gel borate bioactive glasses(BGs)are promising ion-releasing biomaterials for wound healing applications.Here,we report the synthesis of a series of binary B_(2)O_(3)-CaO borate BGs(CaO ranging from 50 to 90mol%)using a sol-gel-based method.The influence of CaO content in B_(2)O_(3)-CaO borate BG on morphology,structure and ion release behavior was investigated in detail.Reduced dissolution(ion release)and crystallization could be observed in borate BGs when CaO content increased,while the morphology was not significantly altered by increasing CaO content.Our results evidenced that the ion release behavior of borate BGs could be tailored by tuning the B_(2)O_(3)/CaO molar ratio.We also evaluated the in vitro cytotoxicity,hemostatic,antibacterial and angiogenic activities of borate BGs.Cytocompatibility was validated for all borate BGs.However,borate BGs exhibited composition-dependent hemostatic,antibacterial and angiogenic activities.Generally,higher contents of Ca in borate BGs facilitated hemostatic activity,while higher contents of B_(2)O_(3) were beneficial for pro-angiogenic activity.The synthesized sol-gel-derived borate BGs are promising materials for developing advanced wound healing dressings,given their fast ion release behavior and favorable hemostatic,antibacterial and angiogenic activities.

关键词： borate glasses sol-gel processing glass composition wound healing

Towards engineering a portable platform for laparoscopic pre-training in virtual reality with haptic feedback

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虚拟现实与智能硬件（中英文） 2024年第2期6卷 83-99页

作者： Hans-Georg ENKLER Wolfgang KUNERT Stefan PFEFFER Kai-Jonas BOCK Steffen AXT Jonas JOHANNINK christoph REICH Furtwangen University 78120 FurtwangenGermany University Hospital and Faculty of Medicine Tuebingen 72076 TuebingenGermany

Background Laparoscopic surgery is a surgical technique in which special instruments are inserted through small incision holes inside the body.For some time,efforts have been made to improve surgical pre training through practical exercises on abstracted and reduced models.Methods The authors strive for a portable,easy to use and cost-effective Virtual Reality-based(VR)laparoscopic pre-training platform and therefore address the question of how such a system has to be designed to achieve the quality of today's gold standard using real tissue specimens.Current VR controllers are limited regarding haptic feedback.Since haptic feedback is necessary or at least beneficial for laparoscopic surgery training,the platform to be developed consists of a newly designed prototype laparoscopic VR controller with haptic feedback,a commercially available head-mounted display,a VR environment for simulating a laparoscopic surgery,and a training concept.Results To take full advantage of benefits such as repeatability and cost-effectiveness of VR-based training,the system shall not require a tissue sample for haptic feedback.It is currently calculated and visually displayed to the user in the VR environment.On the prototype controller,a first axis was provided with perceptible feedback for test purposes.Two of the prototype VR controllers can be combined to simulate a typical both-handed use case,e.g.,laparoscopic suturing.A Unity based VR prototype allows the execution of simple standard pre-trainings.Conclusions The first prototype enables full operation of a virtual laparoscopic instrument in VR.In addition,the simulation can compute simple interaction forces.Major challenges lie in a realistic real-time tissue simulation and calculation of forces for the haptic feedback.Mechanical weaknesses were identified in the first hardware prototype,which will be improved in subsequent versions.All degrees of freedom of the controller are to be provided with haptic feedback.To make forces tangible in the simulation,characteristic values

关键词： Laparoscopic surgery Training Virtual reality Controller Haptic feedback Kinesthetic skills

Production of the X(4014)as the Spin-2 Partner of X(3872)in e^(+)e^(-)Collisions

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Chinese Physics Letters 2024年第3期41卷 30-36页

作者： Pan-Pan Shi Vadim Baru Feng-Kun Guo christoph Hanhart Alexey Nefediev CAS Key Laboratory of Theoretical Physics Institute of Theoretical PhysicsChinese Academy of SciencesBeijing 100190China School of Physical Sciences University of Chinese Academy of SciencesBeijing 100049China Departamento de F′ısica Te′orica and IFIC Centro Mixto Universidad de Valencia-CSIC Institutos de Investigaci′on de PaternaAptdo.2208546071 ValenciaSpain Institut fur Theoretische Physik II Ruhr-Universitat BochumD-44780 BochumGermany Peng Huanwu Collaborative Center for Research and Education Beihang UniversityBeijing 100191China Institute for Advanced Simulation Institut fur Kernphysik and Julich Center for Hadron PhysicsForschungszentrum JulichD-52425 JulichGermany Jozef Stefan Institute Jamova 391000LjubljanaSlovenia CeFEMA Center of Physics and Engineering of Advanced MaterialsInstituto Superior T′ecnicoAvenida Rovisco Pais 11049-001 LisboaPortugal

In 2021,the Belle collaboration reported the first observation of a new structure in theψ(2S)γfinal state produced in the two-photon fusion process.In the hadronic molecule picture,this new structure can be associatedwith the shallow isoscalar D*D* bound state and as such is an excellent candidate for the spin-2 partner of the X(3872)with the quantum numbers J^(PC)=2^(++)conventionally named X_(2).

关键词： process X(3872) Collisions

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银行的净息差和利率期限结构变化

新金融 2024年第6期 27-33+55页

作者： christoph Memmel Lotta Heckmann-Draisbach 德意志银行

编者按：了解利率变化对银行净息差和各利益相关方的影响至关重要。人们通常主要关注利率水平的变化，然而，利率期限结构的变化也是一大驱动因素，会对银行的利息业务产生重大影响。本文模拟了利率变化对银行净息差的影响，基于利率水... 详细信息

编者按：了解利率变化对银行净息差和各利益相关方的影响至关重要。人们通常主要关注利率水平的变化，然而，利率期限结构的变化也是一大驱动因素，会对银行的利息业务产生重大影响。本文模拟了利率变化对银行净息差的影响，基于利率水平变化和期限结构变化，研究的简化模型可以复制不同银行业务模式的典型特征，简化模型得出的结果与德国中小型银行的定量调查结果基本一致。该模型可以较好地描述银行的利息业务，解释银行净息差的动态变化。本刊摘编此篇德意志银行的工作论文，以飨读者。

关键词：银行净息差利率期限结构利率水平变化债券组合模型

IEC 61850用于数字化配电网若干问题的探讨

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供用电 2024年第5期41卷 2-9页

作者：徐丙垠陈羽赵义奎 christoph Brunner 山东理工大学智能电网研究中心山东淄博255049 山东科汇电力自动化股份有限公司山东淄博255087 IT4Power公司瑞士楚格6300

配电网中智能电子设备(intelligent electronic device,IED)同主站系统之间的互联互通与互操作是配电网实现数字化转型的基础,IEC 61850为数字化配电网的互联互通与互操作提供了信息模型和信息交换的标准解决方案。分析了传统电力远动... 详细信息

配电网中智能电子设备(intelligent electronic device,IED)同主站系统之间的互联互通与互操作是配电网实现数字化转型的基础,IEC 61850为数字化配电网的互联互通与互操作提供了信息模型和信息交换的标准解决方案。分析了传统电力远动通信协议存在的问题,探讨了数字化配电网采用IEC 61850的必要性与优势,介绍了IEC 61850用于配电网的信息模型、通信协议映射与配置方法,以及IEC 61850在国内外配电网的研究与技术推广情况。

关键词： IEC 61850 数字化配电网互联互通互操作信息模型映射方法配置

从欧洲视角探究食物中天然毒素对健康的潜在长期风险

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粮油食品科技 2024年第4期 1-15+253-254页

作者： Rudolf KRSKA christoph BUESCHL Mari ESKOLA Chris ELLIOTT 维也纳自然资源与生命科学大学生物分析与农业代谢组学研究所农业生物技术系贝尔法斯特女王大学生物科学学院全球食品安全研究所 Medifiles临床实验有限公司

食品中完全无毒素的理念往往更接近于一种理想化的幻想而非现实。为辨别并优先处理长期摄入食品累积的有害物质，特别是天然毒素带来的健康风险，我们开展了一项针对性研究。通过审查100多项主要由欧洲食品安全局（EFSA）开展的欧洲层... 详细信息

食品中完全无毒素的理念往往更接近于一种理想化的幻想而非现实。为辨别并优先处理长期摄入食品累积的有害物质，特别是天然毒素带来的健康风险，我们开展了一项针对性研究。通过审查100多项主要由欧洲食品安全局（EFSA）开展的欧洲层面的风险评估研究来评估食品供应的安全性。深入探讨了欧洲消费者长期接触的食品中潜在天然毒素对健康的影响，以及关于特定毒素的研究发现。此外，尝试对长期接触与公众健康有关的食品化学污染物所构成的风险进行排名。黄曲霉毒素被列为食品中第三大重要的化学污染物，因其具有很强的致癌能力，会导致人类患肝癌，加之欧洲谷物类食品消费量高，导致了高风险。虽然吡啶碱类物质具有基因毒性和致癌性，但由于人类接触这类植物毒素的来源有限——例如通过茶、蜂蜜或草药，它们在榜单中仅排第五。

关键词：欧洲视角天然毒素食品供应安全性风险评估