Dr. Marco Drache

Scientific staff

Publications

"Modeling complex semi-batch vinyl acetate polymerization processes"
A. Feuerpfeil, M. Drache, L.-A. Jantke, T. Melchin, J. Rodríguez-Fernández, S. Beuermann
Ind. Eng. Chem. Res2021, 60, 18256

"Self-initiated butyl acrylate polymerizations in bulk and in solution monitored by in-line techniques"
J. Mätzig, M. Drache, S. Beuermann
Polymers  2021, 13, 2021

"Design of polymer-embedded heterogeneous fenton catalysts for the conversion of organic trace compounds"
C. Horn, S. Ihmann, F. Müller, D. Pospiech, K. Borchert, R. Hommel, K. Qin, K. Licha, P.J. Allertz, M. Drache
Processes  2021, 9, 942

"Identification of β scission products from free radical polymerizations of butyl acrylate at high temperature"
M. Drache, M. Stehle, J. Mätzig, K. Brandl, M. Jungbluth, J. C. Namyslo, A. Schmidt, S. Beuermann
Polym. Chem. 2019, 10, 1956

"Polymer electrolyte membranes prepared by graft copolymerization of 2‒acrylamido‒2‒methylpropane sulfonic acid and acrylic acid on PVDF and ETFE activated by electron beam treatment"
X. Ke, Y. Zhang, U. Gohs, M. Drache, S. Beuermann
Polymers2019, 11, 1175

"Combination of nuclear magnetic resonance spectroscopy and nonlinear methods to analyze the copolymerization of phosphonic acid derivatives"
M. Heinze, S. Starke, M. Händler, H. Komber, M. Drache, N. Moszner, B. Voit, D. Pospiech
J. Appl. Polym. Sci.2019, 136, 48256

"Preparation of polymer electrolyte membranes via radiation induced graft copolymerization on ETFE using the crosslinker N, N’-methylenebis(acrylamide)"
X. Ke, M. Drache, U. Gohs, U. Kunz, S. Beuermann
Membranes2018, 8, 102

"Kinetic Monte Carlo simulation based detailed understanding of the transfer processes in semi-batch iodine transfer emulsion polymerizations of vinylidene fluoride"
F. Brandl, M. Drache, S. Beuermann
Polymers 2018, 10, 1008

M. Drache, K. Brandl, R. Reinhardt, S. Beuermann
Ab initio Kinetic Monte Carlo Simulation of Seeded Emulsion Polymerizations of Styrene
Phys. Chem. Chem. Phys.2018, 20, 10796-10805

F. Brandl, M. Drache, J. E. S. Schier, T. Nentwig, D. Contreras-López, E. Saldívar-Guerra, R. A. Hutchinson, S. Beuermann
Propagation kinetics of isoprene - glycidyl methacrylate copolymerizations investigated via PLP-SEC
Macromol. Rapid Commun.2017, 38, 1700105

X. Li, A. R. dos Santos, M. Drache, X. Ke, U. Gohs, T. Turek, M. Becker, U. Kunz, S. Beuermann
Polymer electrolyte membranes prepared by pre-irradiation induced graft copolymerization on ETFE for vanadium redox flow battery applications
Journal of Membrane Science2017, 524, 419-427.

B. Hosemann, M. Drache, S. Beuermann
Experimentally calibrated random walk of branched polymers: a pragmatic approach
Macromol. Theory Simul.2016, 25, 508-517.

B. Hosemann, M. Drache, S. Beuermann
Advanced kinetic parameter fit applied to radical copolymerizations
Macromol. Symp.2016, 370, 17-25.

X. Li, M. Drache, U. Gohs, S. Beuermann
Polymerelektrolytmembranen für Hoch- und Niedertemperatur-Brennstoffzellen aus strahlungsinduzierter Pfropfcopolymerisation
Chem. Ing. Tech.2016, 88, 607-615.

X. Li, M. Drache, X. Ke, U. Gohs, S. Beuermann
HTPEM application of (acrylic acid - co - hydroxyethyl methacrylate) graft ETFE doped with phosphoric acid
Macromol. Mater Eng. 2016, 301, 56-64.

X. Li, M. Drache, U. Gohs, S. Beuermann
Novel concept of polymer electrolyte membranes for high-temperature fuel cells based on ETFE grafted with neutral acrylic monomers
Journal of Membrane Science2015, 495, 20-28.

M. Drache, B. Hosemann, T. Laba, S. Beuermann, Modeling of Branching Distributions in Butyl Acrylate Polymerization Applying Monte Carlo Methods Macromol. Theory Simul.2015, 24, 301-310.

R. Siegmann, M. Drache, S. Beuermann
Detailed Copolymerization Propagation Kinetics of Homogeneous Phase VDF-HFP Copolymerizations in Supercritical CO2
Journal of Fluorine Chemistry2014, 159, 48-56.

R. Siegmann, M. Drache, S. Beuermann
Propagation rate coefficients for vinylidene fluoride homopolymerizations
Macromolecules2013, 46, 9507-9514.

M. Drache, G. Drache
Simulating Controlled Radical Polymerizations with mcPolymer—A Monte Carlo Approach
Polymers 2012, 4, 1416-1442.

O. I. Strube, L. Nothdurft, M. Drache, G. Schmidt-Naake
A Novel Bifunctional Trithiocarbonate for Styrene and Methacrylate RAFT Polymerization
Macromolecular Chemistry and Physics2011, 212, 574-582.

F. Schaeffner, M. Drache, G. Schmidt-Naake
Copolymerization of 2-acrylamido-2-methyl-1-propanesulfonic acid and 1-vinylimidazole in ethanol
Macromolecular Materials and Engineering2011, 296, 535-543.

M. Drache
Modeling the Product Composition During Controlled Radical Polymerizations with Mono- and Bifunctional Alkoxyamines
Macromolecular Symposia2009, 275-276, 52-58.

M. Drache, G. Schmidt-Naake
Initialization of RAFT agents with different leaving groups - determination of the transfer coefficients.
Macromolecular Symposia2008, 271, 129-136.

M. Drache, G. Schmidt-Naake
RAFT Polymerization - Investigation of the Initialization Period and Determination of the Transfer Coefficients
Macromolecular Symposia2007 259, 397-405.

 G. Schmidt-Naake, M. Drache, F. Koppers
Kinetische Studien und Monte Carlo-Simulation der radikalischen Ter- und Tetrapolymerisation
Chemie Ingenieur Technik2007 79, 1155-1164.

M. Drache, K. Mandel, G. Schmidt-Naake
Kinetics of nitroxide-controlled radical polymerization during the non-stationary state
Polymer 2007 7, 1875-1883.

C. Schmidt, F. Merz, S. Jiang, M. Drache, G. Schmidt-Naake
Copolymerization Behavior of Acid-Base Monomer Systems and Properties of their corresponding Polymers
Macromolecular Materials and Engineering2007 4, 428-436.

C. Barner-Kowollik, M. Buback, B. Charleux, M. L. Coote, M. Drache, T. Fukuda, A. Goto, B. Klumperman, A. B. Lowe, J. B. Mcleary, G. Moad, M. J. Monteiro, R. D. Sanderson, M. P. Tonge and P. Vana
Mechanism and Kinetics of Dithiobenzoate-Mediated RAFT Polymerization, 1: The Current Situation
Journal of Polymer Science, Part: A, Polymer Chemistry2006 44, 5809-5831.

M. Drache, G. Schmidt-Naake, M. Buback, P. Vana
Modeling RAFT polymerization kinetics via Monte Carlo methods: cumyl dithiobenzoate mediated methyl acrylate polymerization
Polymer 2005 46, 8483-8493.

M. Drache, K. Drees, G. Schmidt-Naake
Implementation of a kinetic model of the RAFT polymerization with a Monte Calrlo Method
DECHEMA Monographs2004 138, 479.

S. Beuermann, M. Buback, M. Drache, D. Nelke, G. Schmidt-Naake
Solvation of poly(methyl acrylate) and poly(vinyl acetate) by CO2 studied via atomistic Monte Carlo simulation techniques
e-polymers2004, 2

M. Drache, J. Reichel
Simulation of Polymer Aggregates as a Method to Investigate the Solvent Effect on Blend Complexation and the Relative Strength of H-Bonding Groups in Blends
Macromolecular Theory and Simulations2002 11, 878-883.

G. Schmidt-Naake, M. Drache, M. Weber
Combination of Mechanochemical Degradation of Polymers with Free-Radical Polymerization
Macromolecular Chemistry and Physics2002 203, 2232-2238.

F. Zeuner, N. Moszner, M. Drache, V. Rheinsberger
Synthesis and dental aspects of acrylic phosphonic acids
Phosphorus Sulfur and Silicon and the related Elements2002 177, 2263

G. Schmidt-Naake, C. Taube, M. Drache
Control of Macromolecular Structure through N-Oxyle Controlled Free Radical Polymerization
DECHEMA Monographs2001 137, 517

M. Drache, J. Reichel, G. Schmidt-Naake
Simulation of Polymer Aggregates
DECHEMA Monographs2001 137, 183

G. Schmidt-Naake, A. Frendel, M. Drache, G. Janke
Mechanochemical modification of polystyrene and polymethylmethacrylate
Chemical Engineering & Technology2001 24, 889-894

N. Moszner, F. Zeuner, S. Pfeiffer, I. Schurte, V. Rheinsberger, M. Drache
Monomers for Adhesive Polymers, 3. Synthesis, Radical Polymerization and Adhesive Properties of Hydrolytically Sable Phosphonic Acid Monomers
Macromolecular Materials and Engeneering2001 286, 225-231

A. Frendel, M. Drache, G. Janke, G. Schmidt-Naake
Mechanochemische Modifizierung von Polystyrol und Polymethylmethacrylat Chemie Ingenieur Technik2000 72, 391-396

M. Drache, T. Weber, G. Schmidt-Naake
Conformation analysis of Poly(styrene-alt-maleic anhydride) in solvents
Angewandte Makromolekulare Chemie1999 273, 69-74

G. Schmidt-Naake, M. Drache, C. Taube
TEMPO-controlled free radical suspension polymerization
Angewandte Makromolekulare Chemie1999  265, 62-68

M. Drache, A. Koch, G. Schmidt-Naake
N-Oxyl-kontrollierte radikalische Lösungspolymerisation von Styrol
Angewandte Makromolekulare Chemie1999  265, 47-54

Ch.-H. Han, M. Drache, G. Schmidt-Naake
Influence of N-oxyls on the free radical autopolymerization of styrene
Angewandte Makromolekulare Chemie1999 264, 73-81

Ch.-H. Han, M. Drache, H. Baethge, G. Schmidt-Naake
4-Oxo-2,2,6,6-Tetramethylpiperidine-1-oxyl (4-Oxo-TEMPO)- und 4-Acetamido-2,2,6,6- Tetramethylpiperidine-1-oxyl (4-Acetamido-TEMPO)-controlled free radical polymerization of styrene
Macromolecular Chemistry and Physics1999 200, 1779-1783

G. Schmidt-Naake, M. Drache, Ch.-H. Han, A.Koch
Simulation of N-Oxyl-Controlled Radical Polymerization of Styrene
DECHEMA Monographs1998 134, 599

G. Schmidt-Naake, K. Leonhardt, M. Drache
The influence of CT-complexes on the copolymerization behavior of cyclic maleic acid derivates with donor monomers
Macromolecular Chemistry and Physics1998 199, 353-361

Conference Contributions

A. Feuerpfeil, M. Drache, S. Beuermann, L. Jantke, T. Melchin
Kinetic Monte Carlo simulation of semi-batch vinyl acetate radical polymerizations in solution
13th International Workshop on Polymer Reaction Engineering, Hamburg, 2019

J. Schwaderer, F. Brandl, M. Drache, S. Beuermann
Detailed Understanding of the Transfer Processes in the Semi-Batch Iodine Transfer Emulsion Polymerization of VDF Based on Kinetic Monte Carlo Simulation
13th International Workshop on Polymer Reaction Engineering, Hamburg, 2019

M. Drache, J. Mätzig, M. Jungbluth, S. Beuermann
Kinetic Monte Carlo simulation of butyl acrylate radical polymerizations at high temperatures
13th International Workshop on Polymer Reaction Engineering, Hamburg, 2019

J. Mätzig, M. Stehle, M. Drache, K. Brandl, M. Jungbluth, J. C. Namyslo, A. Schmidt, S. Beuermann
Identification of β scission products from free radical polymerizations of butyl acrylate at high temperature
13th International Workshop on Polymer Reaction Engineering, Hamburg, 2019

M. Drache, K. Brandl, S.Beuermann
Ab initio kinetic monte carlo simulation of seeded emulsion polymerization
MACRO18 World Polymer Congress, Cairns, Queensland, Australien 2018

M. Drache, B. Hosemann, S. Beuermann
Multiscale Monte Carlo simulation: coupling random walk with kinetic models
Fifth International Symposium Frontiers in Polymer Science, Sevilla, Spanien 2017

M. Drache, B. Hosemann, S. Beuermann
Deep insight into polymer architecture of branched poly(VDF-co-HFP) by kinetic Monte Carlo simulations
Fifth International Symposium Frontiers in Polymer Science, Sevilla, Spanien 2017

M. Drache, X. Ke, X. Li, U. Gohs, S. Beuermann
Proton exchange membranes from grafting polymerization of (meth)acrylate monomers on ETFE films - synthesis and fuel cell application
Electrochemistry 2016, Goslar

M. Drache, X. Li, U. Gohs, S. Beuermann
Proton exchange membranes for high temperature fuel cells: synthesis by radiation induced graft polymerization and fuel cell tests
IUPAC World Polymer Congress, MACRO 2014, Chiang Mai, Thailand

M. Drache, T. Laba, B. Hosemann, S. Beuermann
Microstructure of poly(butyl acrylate) derived fromMonte Carlo simulations with mcPolymer
11th Workshop on Polymer Reaction Engineering, Hamhurg 2013

M. Drache, G. Schmidt-Naake
Modeling the Product Composition and Molecular Weight Distribution of the RAFT-Polymerization by Monte Carlo Methods
Makromolekulares Kolloquium Freiburg 2012

G. Schmidt-Naake, M. Drache
Polyvinylpyrrolidone membranes - Universal PEM fuel cells in the temperature range from 30 to 180 °C
World Congress on Engineering and Technology, Shanghai, China, 2011

M. Drache, G. Schmidt-Naake
Modeling the RAFT-Polymerization in the Pre- and Main- Equilibrium by Monte Carlo Methods
World Congress on Engineering and Technology, Shanghai, China, 2011

M. Drache, G. Schmidt-Naake
Determination of transfer-coefficients in the pre- and main-equilibrium of the RAFT-polymerization
International Chemical Congress of Pacific Basin Societies (Pacifichem), Hawaii USA, 2010

O. I. Strube, L. Nothdurft, M. Drache, G. Schmidt-Naake
Synthesis of Copolymers and Block Copolymers via RAFT Polymerization and Characterization by MALDI-TOF MS
Makromolekulares Kolloquium Freiburg 2010

M. Drache, G. Schmidt-Naake
Initialization of RAFT agents with different leaving groups
Zing Polymer Chemistry Conference, Mexico, 2009

M. Drache, G. Schmidt-Naake, D. Boschmann, P. Vana
Initialization of multifunctional RAFT agents
42th IUPAC International Symposium on Macromolecules, MACRO2008, Taipei, Taiwan

M. Drache, F. Rost, G. Schmidt-Naake
Diskontinuierliche und halbkontinuierliche radikalische Ter- und Tetrapolymerisation - Kinetische Studien und Monte Carlo-Simulationen
Jahrestreffen Reaktionstechnik, Würzburg 2008

P. Vana, D. Boschmann, M. Maenz, M. Drache, M. Froehlich and G. Zifferer
Mechanism and Applications of Z-RAFT Star Polymerization
10th Pacific Polymer Conference, Kobe Japan 2007

M. Drache, G. Schmidt-Naake
Initialization of RAFT agents with different leaving groups - determination of the transfer coefficients
Modelling, Monitoring and Control of Polymer Properties, Lyon France 2007

M. Drache, G. Schmidt-Naake
Kinetic Studies and Monte Carlo Simulations of radical Ter- and Tetrapolymerisations
European Congress of Chemical Engineering, Kopenhagen, DK 2007

M. Drache, G. Schmidt-Naake
Modeling Controlled Radical Polymerizations with Monte Carlo methods
International Conference on Polymer processing, Beijing China 2007

M. Drache, G. Schmidt-Naake
RAFT polymerization - kinetic investigation of the initialization period
Hangzhou International Polymer Forum, Hangzhou China 2007

M. Drache, G. Schmidt-Naake
Investigation of the initialization period of RAFT-mediated polymerization with RAFT-agents containing different leaving groups
41th IUPAC International Symposium on Macromolecules, MACRO2006, Rio de Janeiro, Brazil

G. Schmidt-Naake, S. Flakus, M. Drache
Alkoxyamine-Monomers in SFRP- A way to graft copolymers
41th IUPAC International Symposium on Macromolecules, MACRO2006, Rio de Janeiro, Brazil

M. Drache, G. Schmidt-Naake
RAFT polymerization - kinetic investigation of the initialization period
4th International Symposium on Radical Polymerization: Kinetics and Mechanism, Lucca Italy 2006

M. Drache, G. Schmidt-Naake
Kinetics of nitroxide controlled radical polymerization during the non-stationary state
4th International Symposium on Radical Polymerization: Kinetics and Mechanism, Lucca Italy 2006

G. Schmidt-Naake, I. Wöcht, M. Drache
Radical Polymerization in Ionic Liquids – New Dimension of Solvent Influence
Infotag Prozeßintensivierung, DECHEMA 2006

F. Merz, C. Schmidt, O. Knöpfelmacher, M. Drache, G. Schmidt-Naake
Physico-chemical properties of polymerizable ionic liquid monomers and their polymers
92nd Bunsen Colloquium - Physical Chemistry in Ionic Liquids, Clausthal 2006

F. Merz, C. Schmidt, M. Drache, G. Schmidt-Naake
Copolymerization Behaviour of Proton Donor and Acceptor Monomer Mixtures and Polymerization of the Corresponding Ionic Liquids
Makromolekulares Kolloquium Freiburg 2006

M. Drache, G. Schmidt-Naake
Modeling RAFT polymerization kinetics via Monte-Carlo methods
7th World Congress of Chemical Engineering, Glasgow 2005

M. Drache, K. Drees, G. Schmidt-Naake
Implementation of a kinetic model of the RAFT polymerization with a Monte Calrlo Method
8th International congress on polymer reaction engineering Hamburg 2004

M. Drache, G. Schmidt-Naake, M. Buback, P. Vana
Modeling RAFT Polymerization Kinetics via Monte-Carlo Methods
40th IUPAC International Symposium on Macromolecules, MACRO2004, Paris, France

G. Schmidt-Naake, M. Drache
Stars and Star-like Block copolymers by the nitroxide controlled free radical polymerization – Synthesis and Modeling
40th IUPAC International Symposium on Macromolecules, MACRO2004, Paris, France

K. Drees, M. Drache, G. Schmidt-Naake
RAFT-Polymerisation -Verbrauch der RAFT-Reagenzien
GDCh-Fachgruppentagung Makromolekulare Chemie Düsseldorf 2004

M. Drache, K. Drees, G. Schmidt-Naake
Implementation eines Kinetischen Modells der RAFT-Polymerisation mittels einer Monte-Carlo-Methode
GDCh-Fachgruppentagung Makromolekulare Chemie Düsseldorf 2004

M. Drache, K. Drees, G. Schmidt-Naake
Kinetisches Modell der reversiblen Addition-Fragmentation Chain Transfer (RAFT) Polymerisation in Gegenwart von Dibenzyltrithiocarbonaten
Makromolekulares Kolloquium Freiburg 2004

M. Drache, A. Lang, G. Schmidt-Naake
Kraftfeldtypisierung mit SMILES, GDCh-Jahrestagung Chemie München 2003

G. Schmidt-Naake, M. Drache
Modeling of the nitroxide controlled free radical polymerization based on di- or trialkoxyamine used as initiator
4th European Congress of Chemical Engineering Granada 2003

M. Drache, G. Schmidt-Naake
Modeling of the maximum particle loadings in polymer dispersions
4th European Congress of Chemical Engineering Granada 2003

A. Lang, T. Rattei, W. Naumann, K.-H. van Pée, M. Drache
Screening of peptide-partner-complexes with non-preferred structure peptide-partner-docking (NOSPEDO)
2. Biotechnologie-Tag an der Universität Leipzig 2003

M. Drache, K. Mandel, M. Bothe, G. Schmidt-Naake
Sternpolymere und Blockcopolymere mit Di- und Trialkoxyaminen als Initiator - Synthese, Kinetik und Modellierung
Makromolekulares Kolloquium Freiburg 2003

G. Schmidt-Naake, M. Drache, K. Mandel
Stars and Starlike Block Copolymers from Di- and Trialkoxyamine used as Initiator – Modeling and Kinetic
Meeting of the Working Party Polymer Reaction Engineering Barcelona 2002

M. Drache, G. Schmidt-Naake
Modeling of the maximum particle volume fraction in dispersions
Meeting of the Working Party Polymer Reaction Engineering Barcelona 2002

G. Schmidt-Naake, C. Taube, M. Drache
Synthese neuartiger Blockcopolymere durch kontrollierte radikalische Suspensionspolymerisation in einem Öl/Wasser-System im Autoklaven
GVC/DECHEMA-Jahrestagung Wiesbaden 2002

M. Drache, J. Reichel, G. Schmidt-Naake
Simulation of Polymer Aggregates
7th International congress on polymer reaction engineering Hamburg 2001

M. Weber, M. Drache , G. Schmidt-Naake
Combination of mechanochemical degradation of polymers with controlled free-radical polymerization
SML'01 Lucca 2001

A. Bartsch, M. Drache, G. Schmidt-Naake
Synthesis, homo- and copolymerization of macromonomers
SML'01 Lucca 2001

M. Drache, G. Schmidt-Naake
Modeling of Polymer Composition of the N-Oxyle-controlled free radical copolymerization
SML'01 Lucca 2001

G. Schmidt-Naake, G. Janke, A. Frendel, M. Drache
Polymer Modification in a Vibratory Mill
Meeting of the Working Party Polymer Reaction Engineering Lausanne 2001

M. Drache, G. Schmidt-Naake
Modeling of Polymer Composition of the N-Oxyle-controlled free radical copolymerization
meeting of the Working Party Polymer Reaction Engineering Lausanne 2001

M. Drache, G. Schmidt-Naake
Modelling of Kinetics and Polymer Composition of the N-Oxyle-Controlled Free Radical Polymerization up to High Conversion
3th European Congress of Chemical Engineering Nürnberg 2001

M. Drache, M. Weber, G. Schmidt-Naake
Kombination von mechanochemischem Polymerabbau mit kontrollierter radikalischer Polymerisation
Makromolekulares Kolloquium Freiburg 2001

M. Drache, G. Schmidt-Naake
Simulationen zur N-Oxyl kontrollierten Polymerisation von Blockcopolymeren
GDCh-Fachgruppentagung Makromolekulare Chemie Merseburg 2000

M. Drache, T. Weber, G. Schmidt-Naake
Simulation of Molecular Aggregates
37th IUPAC Congress Berlin 1999

G. Schmidt-Naake, M. Drache, S. Butz, C. Taube
Controlled Radical Polymerization : A Reaction Technique with a Future
37th IUPAC Congress Berlin 1999

M. Drache, T. Weber, G. Schmidt-Naake
Konformationsanalyse von Styrol-Maleinsäureanhydrid-Copolymeren in Lösung mittels atomistischer MC-Simulationen
GDCh-Fachgruppentagung Makromolekulare Chemie Mainz 1998

S. Butz, H. Baethge, M. Drache, G. Schmidt-Naake
Kontrollierte radikalische Blockcopolymerisation unter Variation den N-Oxyls am Beispiel von Poly(Styrol)-b-Poly(Styrol-co-Butylmethacrylat) Diblock Copolymeren
GDCh-Fachgruppentagung Makromolekulare Chemie Mainz 1998

G. Schmidt-Naake, S. Butz, Ch-H. Hun, M. Drache
Homo- und Copolymerisation mit „schlafenden Radikalen“
Makromolekulares Kolloquium Freiburg 1997

M. Drache, G. Schmidt-Naake
Anwendung von Molecular Modeling Methoden für die Beschreibung intermolekularer Wechselwirkungen
DECHEMA-Jahrestagung 1995

M. Drache, G. Schmidt-Naake
Beschreibung intermolekularer Wechselwirkungen mittels des Programmoduls EVOCAP
Makromolekulares Kolloquium Freiburg 1994

Contact
Phone: +49 5323 72-2048
Fax: +49 5323 72-3655
E-Mail: marco.drache@tu-clausthal.de

Address
Institut für Technische Chemie
Building C8, Room 038
Arnold-Sommerfeld-Str. 4
38678 Clausthal-Zellerfeld