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Inkjet-based manufacture and mechanical reinforcement of microsieves
Get PDFMicrosieves are permeable membranes with excellent properties for filtration applications. In this thesis the inkjet-technology is applied (1) to manufacture micro-porous microsieves, and (2) to reinforce the mechanical stability of float-cast, nano-porous microsieves:
(1) The current process for inkjet-printed microsieves includes a manual step which is substituted by inkjet printing in order to increase the level of automation. The obtained microsieves are characterized regarding the pore size distribution. Effects which occur during the manufacture and broaden the pore size distribution are identified. Based on the results, the process is improved to obtain fully inkjet-printed microsieves with a narrowed pore size distribution.
(2) The mechanical stability of fragile, float-cast microsieves is improved by the application of inkjet-printed reinforcement patterns on top of the microsieves. A machine is built to combine both technologies of float-casting and inkjet printing. The printing process is improved to manufacture reinforcement patterns of well-defined geometry.Mikrosiebe sind permeable Membranen mit herausragenden Eigenschaften für die Anwendung in der Filtration. In der vorliegenden Dissertation wird die Inkjet-Drucktechnologie angewandt, um (1) mikroporöse Mikrosiebe herzustellen und (2) nanoporöse Mikrosiebe mechanisch zu stabilisieren:
(1) Die Herstellung von Mikrosieben mittels Inkjet-Druck beinhaltet momentan einen manuellen Schritt, der durch einen Inkjet-Druckschritt ersetzt wird, um den Automatisierungsgrad des Verfahrens zu erhöhen. Die Mikrosiebe werden bezüglich der Porengrößenverteilung untersucht. Auftretende Effekte, die die Porengrößenverteilung verbreitern, werden identifiziert. Aus den Resultaten dieser Analyse wird der Prozess optimiert, um Mikrosiebe mit einer engen Porengrößenverteilung herzustellen.
(2) Die mechanische Stabilität von fragilen Mikrosieben, die mittels Float-Casting hergestellt werden, wird durch das Aufbringen einer Stützstruktur mittels Inkjet-Druck verstärkt. Ein Maschinensetup wird aufgebaut um beide Technologien des Float-Castings und des Inkjet-Drucks zu kombinieren. Weiterhin wird der Prozess dahingehend optimiert, Stützstrukturen mit wohl-definierten Parametern zu erzielen
Aktuelles aus dem deutschen und europäischen Urheberrecht unter besonderer Berücksichtigung von Open Access-Lizenzierungen
Get PDFVortrag über aktuell bedeutsame Probleme des Urheberrechts mit dem Schwerpunkt Open Access-Lizenzierun
Development of a concept for Over The Air Programming of Sensor Nodes
Get PDFNowadays, wireless sensor networks can be found in many new application areas. In these sensor networks there may exit a part of the network which are difficult to access or lie in a wide area, far apart. A change in the software (e.g., function update or bug fix) can entail reprogramming of all sensor nodes. This is very time consuming and labour intensive, if the patching has to be done manually for each individual sensor nodes.
In the area of mobile phones, the over the air (OTA) update function has been established very well with good reliability. In embedded systems such as sensor nodes, where resources are severely restricted, an update cannot be stored but must be programmed directly with the transfer. For this to be possible, a lot of basic functionality is needed to be established to correct errors or to be able to resume a failed programming.
Within the framework of this thesis a concept for the transmission and distribution of the firmware and programming the sensor node is established. Focus here is to optimize the use of resources and to provide basic functionality within the programming mode
Development of an Automation Test Setup for Navigation Data Processing
Get PDFWith the development of Advanced Driving Assistance Systems (ADAS) vehicles have undergone better experience in field of safety, better driving and enhanced vehicle systems. Today these systems are one of the fastest growing in automotive domain. Physical parameters like map data, vehicle position and speed are crucial for the advancement of functionalities implemented for ADAS.
All the navigation map databases are stored in proprietary format. So for the ADAS application to access this data an appropriate interface has to be defined. This is the main aim of Advance Driver Assistant Systems Interface Specifications (ADASIS) consortium. This new specification allows a coordinated effort of more than one industry to improve comfort and fuel efficiency.
My research during the entire duration of my master thesis mainly focuses on two stages namely XML Comparator and CAN stream generation stages from ADASIS Test Environment that was developed in our company. In this test environment ADASIS Reconstructor of our company is tested against the parameters of Reference Reconstructor provided by ADASIS consortium. The main aim of this environment is to develop a Reconstructor which will adhere to all the specifications given in ADASIS Reconstructor.
My implementation in this master thesis focuses on two stages of test environment setup which are XML Comparison and CAN Stream Generation Tool respectively. Prior to my working, these stages lacked in-depth research and usability features for further working
Experimental and theoretical studies on germanium-containing precursors for twin polymerization
Get PDFIm Fokus dieser Arbeit standen zwei Ziele. Zum einem war es Forschungsgegenstand, dass Konzept der Zwillingspolymerisation auf germaniumhaltige, molekulare Vorstufen wie zum Beispiel Germylene, spirozyklische Germaniumverbindungen und molekulare Germanate zu erweitern und somit organisch-anorganische Komposite beziehungsweise Hybridmaterialien darzustellen. Dazu wurden neuartige Germaniumalkoxide auf der Basis von Benzylalkoholaten, Salicylalkoholaten sowie Benzylthiolaten synthetisiert, charakterisiert und auf ihre Fähigkeit Komposite beziehungsweise Hybridmaterialien über den Prozess der Zwillingspolymerisation zu erhalten studiert.
Ein zweites Ziel dieser Arbeit war es, Beziehungen zwischen der Struktur und der Reaktivität dieser molekularen Vorstufen sowie deren Einfluss auf die Eigenschaften der erhaltenen Polymerisationsprodukte zu identifizieren und systematisch zu untersuchen. Hierfür wurden zum einen verschiedene Substituenten, welche unterschiedliche elektronische sowie sterische Eigenschaften aufweisen, an den aromatischen Einheiten der molekularen Vorstufen eingeführt. Die Effekte der Substituenten auf den Prozess der Zwillingspolymerisation und auf die Eigenschaften der Komposite beziehungsweise Hybridmaterialien wurden für die Verbindungsklasse der Germanium(II)salicylalkoholate, der molekularen Germanate sowie der spiro-zyklischen Siliziumsalicylalkoholate untersucht. Spirozyklische Siliziumsalicylalkoholate, wie zum Beispiel 4H,4’H-2,2‘-Spirobi[benzo[d][1,3,2]dioxasilin], wurden im Rahmen dieser Arbeit mit einbezogen, da sie aufgrund ihres nahezu idealen Zwillingspolymerisationsprozesses geeignete Modelverbindungen für Reaktivitätsstudien darstellen. Zudem wurde der Einfluss der Substituenten auf die Charakteristika der aus den Kompositen beziehungsweise Hybridmaterialien erhaltenen Folgeprodukte (poröse Kohlenstoffmaterialien und oxydische Materialien) studiert. Des Weiteren wurde eine Serie von spirozyklischen Germaniumthiolaten, welche isostrukturell zu 4H,4’H-2,2‘-Spirobi[benzo[d][1,3,2]dioxasilin] sind, synthetisiert, um systematisch den Einfluss der Chalkogenide, Sauerstoff und Schwefel, in benzylständiger sowie phenylständiger Position auf deren Reaktionsvermögen im Polymerisationsprozess zu untersuchen.
Die experimentellen Ergebnisse zu den Struktur-Reaktivitätsbeziehungsstudien wurden, soweit es jeweils durchführbar war, mittels quantenchemische Rechnungen validiert und die daraus gezogenen Schlüsse in die Diskussion zur Interpretation der experimentellen Ergebnisse mit einbezogen.:Contents
List of Abbreviations S. 11
1 Introduction S.14
2 Germanium alkoxides and germanium thiolates S. 18
2.1 Preamble S. 18
2.2 Germanium alkoxides S. 18
2.2.1 Germanium(II) alkoxides S. 20
2.2.2 Germanium(IV) alkoxides S. 23
2.2.3 Alkoxidogermanates S. 29
2.3 Germanium thiolates S. 31
2.3.1 Germanium(II) thiolates S. 33
2.3.2 Germanium(IV) thiolates S. 34
2.3.3 Thiolatogermanates and cationic germanium thiolato transition metal complexes S. 36
2.4 Germanium alkoxido thiolates S. 38
2.5 Concluding remarks S. 40
3 Individual Contributions S. 43
4 Microporous Carbon and Mesoporous Silica by Use of Twin Polymerization: An integrated Experimental and Theoretical Approach on Precursor Reactivity S. 46
4.1 Abstract S. 46
4.2 Introduction S.46
4.3 Results and Discussion S. 48
4.3.1 Synthesis and Characterization S. 48
4.3.2 Thermally induced twin polymerization of monosubstituted Precursors (para position) S.49
4.3.2.1 Studies on reactivity according to thermally induced twin polymerization S. 50
4.3.2.2 Characterization of the hybrid materials as obtained by thermally induced twin polymerization S. 51
4.3.2.3 Thermally induced twin polymerization of di-substituted precursors (ortho and para position) S. 52
4.3.2.4 Conclusions drawn for the thermally induced twin polymerization S. 54
4.3.3 Proton-assisted twin polymerization S. 54
4.3.3.1 Studies on the reactivity according to proton-assisted twin polymerization S.55
4.3.3.2 Characterization of the hybrid materials as obtained by proton-assisted twin polymerization S.56
4.3.3.3 Computational studies on proton-assisted twin polymerization S. 58
4.3.3.4 Conclusions drawn for the process of proton-assisted twin polymerization S. 60
4.3.4 Characterization of the porous materials S.61
4.4 Conclusions S.64
4.5 Experimental Section S. 65
4.5.1 General S.65
4.5.2 General procedure for the synthesis of phenolic resin-silica hybrid materials by thermally induced twin polymerization in melt - exemplified for compound 1 S. 66
4.5.3 General procedure for the synthesis of phenolic resin-silica hybrid materials by proton-assisted twin polymerization in solution - exemplified for compound 1 S. 66
4.5.4 General procedure for the synthesis of microporous carbon - exemplified for hybrid material HM-1T S. 66
4.5.5 General procedure for the synthesis of mesoporous silica - exemplified for hybrid material HM-1T S. 67
4.5.6 Single-Crystal X-ray Diffraction Analyses S. 67
4.5.7 Computational Details S. 67
4.6 Acknowledgments S. 68
4.7 Keywords S.68
4.8 Supporting Information Chapter 4 S. 69
5 Synthesis of germanium dioxide nanoparticles in benzyl alcohols – a comparison S. 82
5.1 Abstract S. 82
5.2 Introduction S. 82
5.3 Results and Discussion S.83
5.4 Conclusions S. 87
5.5 Experimental Section S. 87
5.5.1 General S. 87
5.5.2 Syntheses S. 88
5.5.3 Synthesis of GeO2 in ortho-methoxy benzyl alcohol – sample A S. 88
5.5.4 Synthesis of GeO2 in benzyl alcohol under inert conditions – sample B S. 89
5.5.5 Synthesis of GeO2 in benzyl alcohol under ambient conditions – sample C S. 89
5.6 Acknowledgments S. 89
5.7 Keywords S.89
5.8 Supporting Information Chapter 5 S. 90
6 From a Germylene to an “Inorganic Adamantane”: [{Ge₄(μ-O)₂(μ-OH)₄}{W(CO)₅}₄]∙4THF S. 93
6.1 Abstract S.93
6.2 Introduction S. 93
6.3 Results and Discussion S. 94
6.4 Conclusions S. 98
6.5 Experimental Section S. 99
6.5.1 General S.99
6.5.2 Synthesis of germanium(II) (2-methoxyphenyl)methoxide (9) S. 99
6.5.3 Synthesis of [{Ge4(μ-O)2(μ-OH)4}{W(CO)5}4]·4THF (10·4THF) S. 100
6.5.4 Single-Crystal X-ray Diffraction Analyses S. 100
6.5.4.1 Crystal Data for (9)2 S. 101
6.5.4.2 Crystal Data for 10·4THF S. 101
6.5.5 Computational Details S. 101
6.6 Acknowledgments S. 101
6.7 Keywords S.101
6.8 Supporting Information Chapter 6 S. 102
7 Synthesis, characterization and Twin Polymerization of a novel dioxagermine S. 110
7.1 Abstract S. 110
7.2 Introduction S.110
7.3 Results and Discussion S. 111
7.3.1 Single-crystal X-ray diffraction analysis S. 111
7.3.2 IR spectroscopy S. 112
7.3.3 Mass spectrum S. 114
7.3.4 DSC/TGA analysis S. 116
7.3.5 Polymerization S. 117
7.4 Conclusions S. 118
7.5 Materials and Methods S.118
7.5.1 General S. 118
7.5.2 Synthesis of 5-bromo-2-hydroxybenzyl alcohol S. 119
7.5.3 Synthesis of di-tert-butyl-di-ethoxy germane S.119
7.5.4 Synthesis of 6-bromo-2,2-di-tert-butyl-4H-1,3,2-benzo[d]dioxagermine (11) S. 120
7.5.5 Polymerization of compound 11 S. 120
7.5.6 X-ray diffraction analysis of compound 11 S.120
7.5.6.1 Crystal data for compound 11 S.120
7.5.7 Computational Details S.121
7.6 Acknowledgments S.121
7.7 Keywords S. 121
7.8 Supporting Information Chapter 7 S. 122
8 Intramolecular C-O Insertion of a Germanium(II) Salicyl Alcoholate: A Combined Experimental and Theoretical Study S. 125
8.1 Abstract S.125
8.2 Introduction S. 125
8.3 Results and Discussion S.126
8.3.1 Syntheses and Characterization S. 126
8.3.2 1H NMR Spectroscopic Studies S.132
8.3.3 DFT-D Calculations S.134
8.4 Conclusions S. 137
8.5 Experimental Section S. 138
8.5.1 General S. 138
8.5.2 Synthesis of germanium(II) 2-tert-butyl-4-methyl-6-(oxidomethyl)phenolate (12) S. 139
8.5.3 Synthesis of 2,4,6,8-tetrakis(3-tert-butyl-5-methyl-2-oxidophenyl)methanide-1,3,5,7,2,4,6,8-tetraoxidogermocane (13) S. 139
8.5.3.1 Method a) S.139
8.5.3.2 Method b) S. 140
8.5.4 Synthesis of 7,8'-di-tert-butyl-5,6'-dimethyl-3H,4'H-spiro[benzo[d][1,2]oxager-mole-2,2'-benzo[d][1,3,2]dioxagermine] (14) S. 140
8.5.4.1 Method a) S. 140
8.5.4.2 Method b) S. 141
8.5.4.3 Method c) S. 141
8.5.5 Synthesis of the [4-(dimethylamino)pyridine][germanium(II)-2-tert-butyl-4-meth-yl-6-(oxidomethyl)phenolate] (15) S. 141
8.5.6 1H NMR spectroscopic study i) S. 142
8.5.7 1H NMR spectroscopic study ii) S. 142
8.5.7.1 Method a) S. 142
8.5.7.2 Method b) S. 142
8.5.8 1H NMR spectroscopic study iii) S. 142
8.5.8.1 Method a) S. 142
8.5.8.2 Method b) S. 142
8.5.9 1H NMR spectroscopic study iv) S. 143
8.5.10 1H NMR spectroscopic study of the mixture of complex 15 and 3-tert-butyl-2-hydroxy-5-methylbenzyl alcohol in CDCl3 S. 143
8.5.11 1H NMR spectroscopic study of complex 15 in CDCl3 at elevated temperature S. 143
8.5.12 Reaction of complex 15 at elevated temperature S. 143
8.5.13 Single-crystal X-ray diffraction analyses S. 143
8.5.14 Computational Details S.144
8.6 Acknowledgments S. 145
8.7 Keywords S.145
8.8 Supporting Information Chapter 8 S. 146
9 Porous Ge@C materials via twin polymerization of germanium(II) salicyl alcoholates for Li-ion batteries S. 159
9.1 Abstract S. 159
9.2 Introduction S. 159
9.3 Results and Discussion S. 160
9.3.1 Synthesis and Characterization of germylenes S. 160
9.3.2 Twin polymerization S. 164
9.3.2.1 Studies on the reactivity S. 164
9.3.2.2 Characterization of the hybrid materials obtained by thermally induced twin polymerization S. 166
9.3.3 Synthesis and characterization of porous materials S. 168
9.3.4 Electrochemical measurements S. 170
9.4 Conclusions S. 172
9.5 Experimental Section S.172
9.5.1 General S.172
9.5.2 Synthesis of germanium(II) 2-(oxidomethyl)phenolate (16) S. 174
9.5.3 Synthesis of germanium(II) 4-methyl-2-(oxidomethyl)phenolate (17) S. 174
9.5.4 Synthesis of germanium(II) 4-bromo-2-(oxidomethyl)phenolate (18) S. 175
9.5.5 General procedure for the synthesis of phenolic resin-germanium oxide hybrid materials by thermally induced twin polymerization in melt - exemplified for compound 16 S. 175
9.5.6 General procedure for the synthesis of porous Ge@C materials - exemplified for hybrid material HM-16 S.175
9.5.7 General procedure for the synthesis of germanium oxide - exemplified for hybrid material HM-16 S.176
9.5.8 Single-crystal X-ray diffraction analyses S. 176
9.5.9 Computational Details S. 177
9.5.10 Electrode fabrication, cell assembly and electrochemical measurements S. 178
9.6 Acknowledgments S.178
9.7 Keywords S. 178
9.8 Supporting Information Chapter 9 S.179
10 From molecular germanates to microporous Ge@C via twin polymerization S.199
10.1 Abstract S.199
10.2 Introduction 199
10.3 Results and Discussion S. 201
10.3.1 Syntheses and Characterization S. 201
10.3.2 Twin polymerization of germanate 19 S. 204
10.3.3 Synthesis and characterization of the porous materials S. 205
10.3.4 Electrochemical measurements S.206
10.4 Conclusions S. 207
10.5 Experimental Section S. 208
10.5.1 General S. 208
10.5.2 Synthesis of bis(dimethylammonium) tris[2-(oxidomethyl)phenolate(2-)]germa-nate (19) S. 209
10.5.3 Synthesis of bis(dimethylammonium) tris[4-methyl-2-(oxidomethyl)pheno-late(2-)]germanate (20) S. 210
10.5.4 Synthesis of bis(dimethylammonium) tris[4-bromo-2-(oxidomethyl)pheno-late(2-)]germanate (21) S.210
10.5.5 Synthesis of dimethylammonium bis[2-tert-butyl-4-methyl-6-(oxidomethyl)phe-nolate(2-)][2-tert-butyl-4-methyl-6-(hydroxymethyl)phenolate(1-)]germanate (22) S. 211
10.5.6 Synthesis of phenolic resin-germanium dioxide hybrid materials by thermally induced twin polymerization in melt - HM-19 S. 211
10.5.7 Synthesis of porous Ge@C material C-19 starting from HM-19 S. 212
10.5.8 Synthesis of germanium dioxide material Ox-19 - starting from HM-19 S.212
10.5.9 Single-crystal X-ray diffraction analyses S. 212
10.5.10 Electrode fabrication, cell assembly and electrochemical measurements S.213
10.6 Acknowledgments S. 214
10.7 Keywords S. 214
10.8 Supporting Information Chapter 10 S.215
11 Chiral Spirocyclic Germanium Thiolates – An Evaluation of Their Suitability for Twin Polymerization based on A Combined Experimental and Theoretical Study S.226
11.1 Abstract S.226
11.2 Introduction S. 226
11.3 Results and Discussion S.227
11.3.1 Syntheses and Characterization S. 227
11.3.2 Studies on twin polymerization S.229
11.3.3 Computational studies on proton-assisted twin polymerization S. 232
11.4 Conclusions S. 235
11.5 Acknowledgments S. 236
11.6 Keywords S.236
11.7 Supporting Information Chapter 11 S.237
12 Concluding remarks S. 257
12.1 Discussion S.257
12.1.1 Twin polymerization of germanium-containing precursors S. 257
12.1.2 Reactivity studies of precursors towards their twin polymerization S.260
12.2 Summary and Outlook S. 264
Selbständigkeitserklärung S.266
Curriculum Vitae S.267
Publications S. 268
List of Publications in Peer-Reviewed Journals S. 268
List of Conference Contributions S.269
Research proposals, additional conference and summer school participations S. 270
Acknowledgments S. 271
References S. 27
Welding of incompatible thermoplastic polymers
Get PDFDue to the wide range of properties of plastics (e.g. low density), more and more conventional materials are substituted by polymer materials. Complex requirement profiles on technical parts increase the demand for joining processes that enable the reliable joining of otherwise incompatible thermoplastics. In this case, material bonded connections are approaching their limits. In the following study two incompatible thermoplastic polymers were welded by using polymer blends that are compatible to both components. Industrially relevant thermoplastics polyethylene (PE) and polyamide 12 (PA12) were chosen to demonstrate the potential of an innovative joining technology
Process Window Challenges in Advanced Manufacturing: New Materials and Integration Solutions
Get PDFWith the continued progression of Moore’s law into the sub-14nm technology nodes, interconnect RC and power dissipation scaling play an increasingly important role in overall product performance. As critical dimensions in the mainstream Cu/ULK interconnect system shrink below 30nm, corresponding increases in relative process variation and decreases in overall process window mandate increasingly complex integrated solutions. Traditional metallization processes, e.g. PVD barrier and seed layers, no longer scale for all layout configurations as they reach physical and geometric limitations. Interactions between design, OPC, and patterning also play more and more critical roles with respect to reliability and yield in volume manufacturing; stated simply, scaling is no longer “business as usual”. Restricted design layouts, prescriptive design rules, novel materials, and holistic integration solutions each therefore become necessary to maximize available process windows, thus enabling new generations of cost-competitive products in the marketplace
Requirements and challenges on an alternative indirect integration regime of low-k materials
No full textAn alternative indirect integration regime of porous low-k materials was investigated. Based on a single Damascene structure the intra level dielectric SiO2 or damaged ULK was removed by using HF:H2O solutions to create free standing metal lines. The free spaces between the metal lines were refilled with a spin-on process of a low-k material. The persistence of barrier materials and copper against HF solutions, the gap fill behavior of the used spin on glass on different structure sizes and the main challenges which have to solve in the future are shown in this study
Optimal Control Problems in Finite-Strain Elasticity by Inner Pressure and Fiber Tension
Get PDFOptimal control problems for finite-strain elasticity are considered. An inner pressure or an inner fiber tension is acting as a driving force. Such internal forces are typical, for instance, for the motion of heliotropic plants, and for muscle tissue. Non-standard objective functions relevant for elasticity problems are introduced. Optimality conditions are derived on a formal basis, and a limited-memory quasi-Newton algorithm for their solution is formulated in function space. Numerical experiments confirm the expected mesh-independent performance
Participation in cancer screening among female migrants and non-migrants in Germany: A cross-sectional study on the role of demographic and socioeconomic factors
Get PDFIn many European countries, migrants utilize cancer screening less often than non-migrants. In Germany, in contrast, higher rates of utilization among migrants as compared with non-migrants have been reported. The role of demographic and socioeconomic factors potentially confounding the association between migration status and participation in screening, however, could not be studied. The present study aims to investigate the utilization of cancer screening among migrant and nonmigrant women residing in Germany, adjusting for potential confounders.
We used self-reported information from women surveyed on whether they have ever participated in screening for cancer (n = 11,709). The data was collected as part of a cross-sectional representative telephone survey conducted by the Robert Koch-Institute in 2010. We distinguished between three groups of women: (1) respondents of non-German nationality, those who had immigrated to Germany after their birth or those who have two foreign-born parents (“migrants with two-sided migration background”), (2) respondents who only have one foreign-born parent (“migrant with one-sided migration background”), and (3) all others (“non-migrants”).
To account for confounders, logistic regression analysis was performed. Only individuals proficient in German were included in the survey, allowing to control for a bias arising from poor language proficiency.
84.9% of nonmigrant women, 82.1% of women with a one-sided, and 70.5% of women with a two-sided migration background had utilized screening for cancer at least once in their lifetime before the survey. The adjusted odds ratios (OR) as compared with nonmigrant women were 0.99 (95% confidence interval [95% CI]: 0.77–1.27) and 0.55 (95% CI: 0.47–0.64), respectively.
The study shows that migrant women with a two-sided migration background residing in Germany utilize screening for cancer less often than nonmigrant women—independently of demographic and socioeconomic factors. This is in line with findings from other countries. Likely, barriers that migrant women encounter limit them from taking informed choices. These barriers need to be identified and appropriate measures aiming to enhance informed decision making must be implemented