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245 GHz接收机芯片片外测试与实验

太赫兹科学与电子信息学报 2020年第3期18卷 358-363页

作者：毛燕飞鄂世举 SCHMALZ Klaus SCHeYTT J christoph 颜素莉浙江师范大学工学院浙江金华321000 东南大学毫米波国家重点实验室江苏南京211189 IHP MicroelectronicsFrankfurt Oder15236Germany Heinz Nixdorf Institute Paderborn University33102Germany

为了实现太赫兹气体频谱分析传感器,对245 GHz次谐波接收机芯片的片外测试展开研究。建立了245 GHz次谐波接收机片外测试系统以及基于245 GHz接收机芯片及发射机芯片的气体频谱分析传感器片外展示测试系统,对245 GHz次谐波接收机芯片转... 详细信息

为了实现太赫兹气体频谱分析传感器,对245 GHz次谐波接收机芯片的片外测试展开研究。建立了245 GHz次谐波接收机片外测试系统以及基于245 GHz接收机芯片及发射机芯片的气体频谱分析传感器片外展示测试系统,对245 GHz次谐波接收机芯片转换增益和带宽进行测试。片外测试系统得到15 dB转换增益和15 GHz带宽;片外展示测试系统得到9 dB转换增益和16 GHz带宽。片外测试系统和片外展示测试系统结果基本吻合。在片外展示测试系统中加入气腔,即构成气体频谱分析传感器。与现有同类型传感器相比,本文的次谐波接收机具有高增益、高带宽、集成本地振荡信号、低功耗等优势,非常适用于消费电子领域小体积的智能气体频谱分析传感器。

关键词： 245 GHz次谐波接收机片外测试系统片外展示测试系统气体频谱分析传感器系统高增益高带宽低功耗

Spin-polarized electron beam generation in the colliding-pulse injection scheme

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Matter and Radiation at extremes 2023年第6期8卷 49-62页

作者： Zheng Gong Michael J.Quin Simon Bohlen christoph HKeitel Kristjan Põder Matteo Tamburini Max-Planck-Institut für Kernphysik Saupfercheckweg 169117 HeidelbergGermany Deutsches elektronen-Synchrotron DeSY Notkestr.8522607 HamburgGermany

employing colliding-pulse injection has been shown to enable the generation of high-quality electron beams from laser-plasma ***,by using test particle simulations,Hamiltonian analysis,and multidimensional particle-in-cell simulations,we lay the theoretical framework for spin-polarized electron beam generation in the colliding-pulse injection ***,we show that this scheme enables the production of quasi-monoenergetic electron beams in excess of 80%polarization and tens of pC charge with commercial 10-TW-class laser systems.

关键词： polarized scheme enable

Biodiversity and belowground interactions mediate community invasion resistance against a tall herb invader

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Journal of Plant ecology 2010年第2期3卷 99-108页

作者： christoph Scherber Peter NMwangi Martin Schmitz Michael Scherer-Lorenzen Holger Beßler Christof engels Nico eisenhauer Varvara DMigunova Stefan Scheu Wolfgang WWeisser ernst-Detlef Schulze Bernhard Schmid Agroecology Department of Crop ScienceUniversity of GottingenWaldweg 26D-37073 GottingenGermany Institute of evolutionary Biology and environmental Studies University of ZurichWinterthurerstraße 92CH-8057 ZurichSwitzerland Max Planck Institute for Biogeochemistry Hans-Knoll Straße 10D-07745 JenaGermany Institute of ecology Jena UniversityDornburger Straße 159D-07743 JenaGermany Institut fur Biologie II/Geobotanik Schanzlestr.1D-79104 FreiburgGermany Humboldt Universitat zu Berlin Fachgebiet PflanzenernahrungAlbrecht-Thaer-Weg 4D-14195 BerlinGermany J.F.Blumenbach Institute of Zoology and Anthropology University of GottingenBerliner Str.28D-37073 GottingenGermany K.I.Skryabin All-Russian Institute of Helminthology Bolschaya Tcheryomuschkinskaya str.28117218 MoscowRussia

Aims Species-rich plant communities are hypothesized to be more resistant against plant invasions because they use resources in a more efficient ***,the relative contributions of aboveground competition and belowground interactions for invasion resistance are still poorly *** We compared the performance of Knautia arvensis transplants growing in plots differing in plant diversity both under full competition and with shoots of neighbors tied back to determine the relative strength of aboveground competition in suppressing this test invader without the confounding effect of *** addition,we assessed the effects of belowground competition and soil-borne pathogens on transplant *** Findings Both aboveground competition and plant species richness strongly and independently affected invader *** biomass,height,leaf mass per area and flowering of transplanted individuals of *** decreased with increasing species richness of the host ***-rich and species-poor communities both imposed equally strong aboveground competition on ***,belowground interactions(especially belowground root competition)had strong negative effects on transplant *** addition,the presence of grasses in a plant community further reduced the performance of *** results suggest that belowground competition can render species-rich host communities more suppressive to newly arriving species,thus enhancing community invasion resistance.

关键词： aboveground competition competitive suppression belowground interactions root competition shoot exclusion species richness

Transport in graphene nanostructures

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Frontiers of physics 2011年第3期6卷 271-293页

作者： christoph Stampfer Stefan Fringes Johannes Gfittinger Francoise Molitor Christian Yolk Bernat Terrds Jan Dauber Stephan engels Stefan Schnez Arnhild Jacobsen Susanne Droscher Thomas Ihn Klaus ensslin JARA-FIT and II. Institute of Physics B RWTH Aachen University 52074 Aachen and Peter Griinberg Institute （PCI-9） Forschungszentrum Jiilich 52425 Jiilich Germany Solid State Physics Laboratory ETH Zurich 8093 Zurich Switzerland

Graphene nanostructures are promising candidates for future nanoelectronics and solid-state quan- tum information technology. In this review we provide an overview of a number of electron transport experiments on etched graphene nanostructures. We briefly revisit the electronic properties and the transport characteristics of bulk, i.e., two-dimensional graphene. The fabrication techniques for making graphene nanostructures such as nanoribbons, single electron transistors and quantum dots, mainly based on a dry etching ＂paper-cutting＂ technique are discussed in detail. The limitations of the current fabrication technology are discussed when we outline the quantum transport properties of the nanostructured devices. In particular we focus here on transport through graphene nanoribbons and constrictions, single electron transistors as well as on graphene quantum dots including dou- ble quantum dots. These quasi-one-dimensional （nanoribbons） and quasi-zero-dimensional （quantum dots） graphene nanostructures show a clear route of how to overcome the gapless nature of graphene allowing the confinement of individual carriers and their control by lateral graphene gates and charge detectors. In particular, wo emphasize that graphene quantum dots and double quantum dots are very promising systems for spin-based solid state quantum computation, since they are believed to have exceptionally long spin coherence times due to weak spin-orbit coupling and weak hyperflne interaction in graphene.

关键词： graphene nanostructures electron transport quantum dots

Multimodal nonlinear imaging of atherosclerotic plaques differentiation of triglyceride and cholesterol deposits

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Journal of Innovative Optical Health Sciences 2014年第5期7卷 114-123页

作者： Christian Matthäus Riccardo Cicchi Tobias Meyer Annika Lattermann Michael Schmitt Bernd F.M.Romeike christoph Krafft Benjamin Dietzek Bernhard R.Brehm Francesco S.Pavone Jürgen Popp Leibniz Institute of Photonic Technology(IPHT-Jena)Albert einstein Straβe 9 0T145 JerlaGermany Institute of Physical Chemistry and Abbe Center of PhotonicsFriedrich Schiller University Jena Helmholtzweg 407743 JenaGermany National Institute of Optics National Research Council(INO-CNR)Largo E.Fermi 6-50125FlorenceItaly european Laboratory for Non-Linear Spectroscopy(LeNS)University of Florence Via Nello Carrara 1-50019 Sesto Fiorentino(Firenze)Italy Clinic for Internal Medicine Jena University Hospital Friedrich-Schiller-UniversityErlanger Allee 10107747 JenaGermany Institute of Pathology Department of Neuropathology Jena University Hospital-Friedrich-Schiller-University Erlanger Allee 1010140 JenaGermany Catholic Clinic-Koblenz Intermal Medicine&Cardiology Rudolf Virchow Str.956073 KoblenzGermany

Cardiovascular diseases in general and atherothrombosis as the most common of its individualdisease entities is the leading cause of death in the developed ***,visualizationand characterization of inner arterial plaque composition is of vital diagnostic interest,especilly for the early recognition of vulnerable *** clinical techniques provide valuablemorphological information but cannot deliver information about the chemicai composition ofindividual ***,spectroscopic imaging techniques have recently drawn consider-able *** on the spectroscopic properties of the individual plaque components,as forinstance diferent types of lipids,the composition of atherosclerotic plaques can be analyzedqualitatively as well as ***,we compare the feasibility of multimodal nonlinearimaging combining,two-photon fluorescence(TPF),coherent anti-Stokes Raman scatering(CARS)and second-hamonic generation(SHG)microscopy to contrast composition and mor-phology of lipid deposits against the surrounding matrix of connective tissue with diffractionlimited spatial *** this contribution,the spatial distribution of major constituents of the arterial wall and atherosclerotic plaques like elastin,collagen,triglycerides and cholesterol can be simultaneously visualized by a combination of nonlinear imaging methods,providing a powerful label-free complement to standard histopathological methods with great potential forin vivo application.

关键词： Nonlinear microscopy Raman spectroscopy atherosclerosis.

enzyme-Linked Immunosorbent Assays Using the Recombinant gp51 and p24 of Bovine Leukemia Virus for Immunodetection of the Disease

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Open Journal of Animal Sciences 2017年第3期7卷 241-253页

作者： Alejandra Larsen Santiago Corva Javier Panei christoph Geisler eduardo Mortola Faculty of Veterinary Science National University of La Plata La Plata Argentina CONICeT (CCT-La Plata) La Plata Argentina Department of Immunology Faculty of Veterinary Sciences National University of La Plata La Plata Argentina d Department of Molecular Biology University of Wyoming Laramie WY USA

enzyme-linked immunosorbent assay (eLISA) is often used to test bovine leukemia virus (BLV) infection. However, commercially available kits test in South America detect only antibodies against the gp51 protein. With the aim to improve the sensitivity of the test, we developed here a two-step indirect dual eLISA test that included both proteins p24 and gp51, expressed and produced in e. coli and baculovirus expression system respectively. Two hundred ten BLV sera, stated as double positive or double negative by the combination of commercial agar gel immunodiffusion (AGID) assay and a gp51-eLISA test, were tested with our in house dual rp24/rgp51 eLISA. Firstly, we checked the purified, optimized and standardized proteins as antigen by the checkerboard technique, and set up our in house eLISA test. The concordance correlation coefficient (CCC) and coefficient of variation (CV) intraplate repeatability levels were within the values established by the international standards. The statistical analysis demonstrated the value of sera correctly ranked highest (93.48%), and for 0.3 cutoff, the sensitivity was 95.65% and the specificity 91.30%. In conclusion, the rp24/rgp51 eLISA developed and standardized here demonstrated to have good analytical characteristics to be considered for screening of BLV.

关键词： Bovine Leukemia Virus Indirect Dual eLISA Recombinant Antigens

Assessment of myocardial perfusion by positron emission tomography in patients with end-stage coronary artery disease treated with percutaneous myocardial revascularization

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Chinese Medical Journal 2009年第23期122卷 2807-2813页

作者： Marcus Wiemer Johannes Peter Wielepp Oliver Lindner Wolfgang Burchert christoph Langer Dieter Horstkotte Thomas Butz Department of Cardiology Heart and Diabetes Center North Rhine-Westphalia Ruhr University Bochum Bad Oeynhausen Germany Institute of Radiology Nuclear Medicine and Molecular Imaging Heart and Diabetes Center North Rhine-Westphalia Ruhr University Bochum Bad Oeynhausen Germany

Background Reportedly, patients with persistent refractory angina due to end-stage coronary artery disease （CAD） not amenable to traditional revascularization techniques have experienced symptomatic relief following laser revascularization, either surgical transmyocardial revascularization （TMR） or percutaneous myocardial revascularization （PMR）. In spite of several hypotheses （i.e., channel patency, placebo effect, denervation, neoangiogenesis）, the mechanism of action and the benefit remains controversial. Methods A prospective trial utilizing positron emission tomography （PeT） was conducted as an attempt to correlate quantified myocardial blood flow （MBF） to clinical improvement following PMR. Thirteen consecutive patients with angina class 〉11 in spite of maximal medical treatment underwent PMR with a holmium：yttrium-aluminum-garnet （Ho：YAG） laser. MBF at rest and under hyperemia was assessed by [13N]ammonia PeT at baseline, 3 and 6 months following PMR. Results Mean angina class and exercise tolerance time improved at 6 months compared with baseline （P 〈0.001）. The clinical results were accompanied with an improvement in hyperemic MBF （P=-0.05） and a reduction in minimal coronary resistance （MCR; P 〈0.05） in PMR-treated segments. Opposite effects, reduced hyperemic MBF and increased MCR, were observed in nontreated segments. The increase in MCR in nontreated segments revealed the favorable therapeutic impact achieved in PMR-treated segments. Conclusion The results of this trial utilizing a quantitative technique to quantify myocardial perfusion link clinical improvement post-PMR to neoangiogenesis and consistently improved microcirculation.

关键词： laser revascularization positron emission tomography myocardial blood flow

Strong prognostic value of nodal and bone marrow micro-involvement in patients with pancreatic ductal carcinoma receiving no adjuvant chemotherapy

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World Journal of Gastroenterology 2006年第40期12卷 6515-6521页

作者： emre F Yekebas Dean Bogoevski Michael Bubenheim Bjrn-Christian Link Jussuf T Kaifi Robin Wachowiak Oliver Mann Asad Kutup Guellue Cataldegirmen Lars Wolfram Andreas erbersdobler christoph Klein Klaus Pantel Jakob R Izbicki Department of General Visceral and Thoracic Surgery University Medical Centre of Hamburg-Eppendorf Hamburg Germany Institute of Medical Biometry and epidemiology University Medical Centre of Hamburg-Eppendorf Hamburg Germany Institute of Pathology University Medical Centre of Hamburg-Eppendorf Hamburg Germany Institute of Immunology University of Munich Munich Germany Institute of Tumor Biology University Medical Centre of Hamburg-Eppendorf Hamburg Germany

AIM： To study the prognostic value of adjuvant chemotherapy in patients with pancreatic, ductal adenocarcinoma. MeTHODS： Lymph nodes from 106 patients with resectable pancreatic ductal adenocarcinoma were systematically sampled. A total of 318 lymph nodes classified histopathologically as tumor-free were examined using sensitive immunohistochemical assays. Forty-three （41%） of the 106 patients were staged as pT1/2, 63 （59%） as pT3/4, 51 （48%） as pNo, and 55 （52%） as pN1. The study population included 59 （56%） patients exhibiting G1/2, and 47 （44%） patients with G3 tumors. Patients received no adjuvant chemoor radiation therapy and were followed up for a median of 12 （range： 3.5 to 139） mo.ReSULTS： Immunostaining with Ber-eP4 revealed nodal microinvolvement in lymph nodes classified as ＂tumor free＂ by conventional histopathology in 73 （69%） out of the 106 patients. Twenty-nine （57%） of 51 patients staged histopathologically as pNo had nodal microinvolvement. The five-year survival probability for pN0-patients was 54% for those without nodal microinvolvement and 0% for those with nodal microinvolvement. Cox-regression modeling revealed the independent prognostic effect of nodal microinvolvement on recurrence-free （relative risk 2.92, P = 0.005） and overall （relative risk 2.49, P = 0.009） survival. CONCLUSION： The study reveals strong and independent prognostic significance of nodal microinvolvement in patients with pancreatic ductal adenocarcinoma who have received no adjuvant therapy. The addition of immunohistochemical findings to histopathology reports stratification of patients with may help to improve risk pancreatic cancer.

关键词： Pancreatic ductal adenocarcinoma Nodal microinvolvement Micrometastases

Targeting new ways for large-scale,high-speed surface functionalization using direct laser interference patterning in a roll-to-roll process

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International Journal of extreme Manufacturing 2023年第3期5卷 569-583页

作者： christoph Zwahr Nicolas Serey Lukas Nitschke Christian Bischoff Ulrich Radel Alexandra Meyer Penghui Zhu Wilhelm Pfleging Laser Precision Manufacturing Fraunhofer Institute for Material and Beam Technology(IWS)DresdenGermany Topag Lasertechnik GmbH DarmstadtGermany Institute of Manufacturing Science and engineering Technical University DresdenDresdenGermany Institute for Applied Materials—Applied Materials Physics(IAM-AWP) Karlsruhe Institute of Technology(KIT)Eggenstein-LeopoldshafenGermany

Direct Laser Interference Patterning(DLIP)is used to texture current collector foils in a roll-to-roll process using a high-power picosecond pulsed laser system operating at either fundamental wavelength of 1064 nm or 2nd harmonic of 532 *** raw beam having a diameter of 3 mm@1/e^(2) is shaped into an elongated top-hat intensity profile using a diffractive so-called FBS■-L element and cylindrical *** shaped beam is split into its diffraction orders,where the two first orders are parallelized and guided into a galvanometer *** deflected beams inside the scan head are recombined with an F-theta objective on the working position generating the interference *** DLIP spot has a line-like interference pattern with about 15μm spatial *** fluences of up to 8 J cm^(-2) were achieved using a maximum pulse energy of 0.6 ***,an in-house built roll-to-roll machine was *** this setup,aluminum and copper foil of 20μm and 9μm thickness,respectively,could be *** to current collector structuring coating of composite electrode material took *** case of lithium nickel manganese cobalt oxide(NMC 622)cathode deposited onto textured aluminum current collector,an increased specific discharge capacity could be achieved at a C-rate of 1℃.For the silicon/graphite anode material deposited onto textured copper current collector,an improved rate capability at all C-rates between C/10 and 5℃ was *** rate capability was increased up to 100%compared to reference *** C-rates between C/2 and 2℃,the specific discharge capacity was increased to 200 mAh g^(-1),while the reference electrodes with untextured current collector foils provided a specific discharge capacity of 100 m Ah g^(-1),showing the potential of the DLIP technology for cost-effective production of battery cells with increased cycle lifetime.

关键词： DLIP lithium-ion battery surface texturing copper aluminum