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One of the current issues in the Czech building industry is an efficient implementation of seal joint between constructions. An undesirable penetration of water, moisture or air between structural elements may have a negative effect on their reliability and may also affect the length of expected service life. This issue is addressed in detail in the following paper. The experimental part of the research is aimed at ascertaining the technical properties of sealants and on verification of their potential usage in practise. Furthermore, this article focuses on the preparation and subsequent production of test specimens, and also on the experimental verification of their tensile properties at a temperature of (20 ± 3) °C and (-22 ± 2) °C. For the tests, composite high pressure laminates (i.e. HPL Trespa Meteon) are chosen for the cladding. In order to find the best solution ten types of commonly manufactured industrial sealants is selected. At the same time the emphasis was on representation of sealants in various price categories. The main conclusion of tests is the fact that it is not possible to responsibly choose a suitable material without taking appropriate measurements or having previous experience. A secondary conclusion to this article is the fact that there are significant differences between individual sealants in the results they provide in combination with selected cladding material. Moreover, the method also suggests that the use of the most expensive sealant does not always provide the best results. Jedním z aktuálních problémů v českém stavebnictví je řešení realizace tmelených spojů. Nežádoucí pronikání vody, vlhkosti nebo vzduchu mezi konstrukčními prvky může mít negativní vliv na jejich spolehlivost a může také mít vliv na délku očekávané životnosti. Tato problematika je řešena v následujícím příspěvku. Experimentální část výzkumu je zaměřena na zjištění technických vlastností tmelů a na ověření jejich možného využití v praxi. Kromě toho, je tento příspěvek zaměřen na přípravu a následnou výrobu zkušebních vzorků, a také na experimentální ověření jejich mechanických vlastností při teplotě (20 ± 3) °C a (-22 ± 2) °C. Pro účely zkoušek byl vybrán kompozitní vysokotlaký laminát (tj. HPL Trespa Meteon) pro opláštění. S cílem nalézt nejlepší řešení bylo vybráno deset druhů běžně vyráběných průmyslových tmelů. Zároveň byl kladen důraz na zastoupení tmelů z různých cenových kategorií. Stěžejním závěrem zkoušky je skutečnost, že není možné odpovědně zvolit vhodný materiál a tmel bez předchozích zkušeností nebo experimentálního odzkoušení.

Tez (Yüksek Lisans) -- İstanbul Teknik Üniversitesi, Fen Bilimleri Enstitüsü, 2015, Thesis (M.Sc.) -- İstanbul Technical University, Instıtute of Science and Technology, 2015, Bu tez kapsamında öncelikle temel güç elektroniği elemanları, devreleri ve bunların sürüşü için gerekli devreler incelenmektedir. Sonrasında bir adet yeni yarı iletken teknolojili elemanın güç elektroniği devrelerindeki kayıplara etkisi gösterilmekte ve verimi artırdığı bilinen paralel anahtarlama yöntemine yeni bir bakış getirilmektedir. Yeni yarı iletken teknolojisi olarak günümüzde yavaş yavaş seri üretimine başlanan Galyum Nitrit tabanlı anahtarlama elemanları kullanılmıştır. Bir motor kontrol devresinde Silikon ve GaN elemanlar kullanılarak karşılaştırılmıştır. Yük olarak bir fan yükü kullanılmıştır. Ortam şartları eşitlenerek şebekeden çekilen güç ölçümü yapılmış ve ölçümler alınmıştır. Sonuç olarak GaN tabanlı anahtarların verim avantajı açıkça görülmüştür. Paralel anahtarlama için ise anahtarlama işaretlerinin değiştirilmesi için bir yöntem geliştirilmiştir. Yapı gereği verimin artması için yavaş anahtar elemanın sonra açılıp önce kapanması gerekmektedir. Dolayısıyla anahtarlama işaretinde bir takım manipülasyonların yapılması gerekmektedir. Konu hakkında detaylı bir literatür taraması yapılmıştır. Literatür taraması sonucu, açma ve kapama işaretini aynı anda değiştiren devrelerin ya oldukça pahalı olduğu ya da fazladan mikorişlemci çıkışı gerektirdiği görülmüştür. Bu sorunun çözümü için, basit yapılı bir devre tasarımı yapılmıştır. Temel olarak RC devresinin zaman sabiti hesabıyla çalışan bir tasarım yapılarak simülasyon ve uygulaması yapılarak sonuçları verilmiştir. Devre ile ilgili hesaplamalar yapılmış ve ölçüm sonuçlarıyla karşılaştırılmıştır., Power electronics is one of the most popular topics in electrical engineering. Today's world, power converters, motor drivers, voltage regulators are have a very wide usage. From defence industry to home appliances, from automative to medical electronics, power electronic circuits are everywhere. Since power electronic devices have this popularity, their parameters like lifetime or efficiency become more important. Most of the people working on this field try to focus on improving the lifetime or efficiency of the power electronic circuits rather than inventing a new topology. Especially for home appliances industry, lifetime and efficiency of the system is very important because of the government regulations. For example, compressor motor and motor control circuit for a refridgator should have a very hig efficiency like more than 90% to classify the system as a high-end product. For the reasons above, brushless DC motors or permanent magnet synchronous motors are getting popular everyday. Since they have a good efficiency-torque-speed relationship, their usage in all industries are increasing rapidly. Although this motors are very efficient, they can not work directly with the AC mains. These kind of motors need a motor control circuit to operate and efficiency of this controller is also becomes important. Usually, BLDC or PMSM motors are producted as 3-phase motors and so, they are controlled with a 3-phase inverter circuit. A 3-phase inverter circuit for controlling a motor usually has a harmonic eliminating circuit to obey the regulations. Then an AC to DC converter is used for gathering DC voltage from mains. After that, a six switch inverter is used for controlling the motor. Also there is a low voltage side for the microcontroller, integrated circuits and other peripheral components which is needed to gather the information from the motor and decide the next signal for inverter. It is important to know the basic power electronics circuits topologies to understand how a six switch inverter controlls the motor in terms of speed or torque or both of them. Everything starts with a buck converter, which is used for decreasing the voltage value of the input and gives to the output. Buck circuit is a very simple circuit, just has one switch, one diode, one inductance and one capacitor. Also boost converter is a main converter type, which increases the voltage of the input for the output. Boost converter is again very simple, has the same components with buck, just connected in a different way. In todays power electronics world, most of the circuits derived from buck converter and boost converter. The most obvious example of that is the buc-boost converter. This converter type is used to increase or decrease the voltage, which is needed. Bridge type converters are the basics of motor control circuits. Simply, one can use a buck converter to drive a brushed DC motor, but only operates in one direction since the current flows only one direction. But in a bridge converter, current path can be changed so the direction of the rotation can be changed. That is the reason why the bridge type converters are important in motor control. These converters are based on buck converter, which means they decrease the input voltaage for the output. A half bridge converter includes two switches and two capacitors, whereas a full bridge converter includes four switches to have a perfect control on the current direction. A six switch inverter is based on the half bridge topology. Actually, it is nothing more than three half bridge converters. The middle points of the half brigde converters are connected to the load. In a six switch inverter circuit which is used for a motor control, switches are the most important elements in terms of efficiency. Basicly, one can say that switches decide the efficiency level of the circuit. That is the reason why most of the scientists are working to increase the switching elements performance. There are a few ways to increase the switching performance, like using a new semiconductor technology or parallel switching. Superior semiconductors are the new era for electronics. Silicon Carbide (SiC) and Galium Nitride (GaN) are the most important technologies for today. Most of the semiconductor companies are trying to product a new, cheap and better superior semiconductors. GaN is the main focus point of the companies. SiC technologies are complicated and expensive, but GaN production is easy and cheap. People in the industry says that procedure for production of the GaN may be cheaper than standard Silicone. Many of the market predicters state that by the end of 2010's GaN will replace the Si in semiconductors. A GaN switch has very good switching and conducting performance. To show this in this thesis, a Si based circuit and a GaN based circuit compared in terms of losses in calculation. After that, a motor control circuit is modified for GaN and new switches implemented. Than comparison re-done in the same load conditions, in terms of heating and losses. Results are given. Parallel switching is another way for increasing the efficiency of the circuit. Researchers are working on this technology since the early 90's. Yirming Jiang, Guichao Hua and Fred C. Lee are the founders of the concept with their publication" which shows that it is possible to work with parallel switches. After this work, a lot of researchers worked on this topic and publicated their job. Sakhon Woothipatanapan, Anuwat Jangwanitlert and Phop Cancharoensook, show that a parallel switching method increases the efficiency on motor drives in their publication. This publication is the first in this field for 3-phase implementation of the parallel switching method. Parallel switching needs a very good gate driving circuit in terms of timing. Since a bad gate signal may cause a short circuit, designer must be very careful. For gate driving of parallel switches, there are not many offers. People usually uses two microcontroller outputs for this. Bu it is not an efficient way for gate driving. An ASIC can be a solution for gate drive timing. H.P.Yee, and Dean Liu published "An ASIC to Control the Paralleling of an IGBT with a MOSFET" article and designed an IC for closing time delay. There are some other methods like FPGA based design. But common problem is the high costs of new gate driving circuits. Cheap solutions can not provide opening delay which is important for switching losses. In this thesis, two RC based delay circuits are offered for opening delay and closing delay. Opening delay is for IGBT opening signal and closing delay is for MOSFET closing signal. By this way, IGBT never produces a switching loss ideally since it is under soft switching conditions. Also MOSFET never produces a conduction loss if it is selected correctly. At first, concept design of the circuits are made and explained. After that, switching elements are selected and delay times are desired. Than some calculation for delay times are done and values of the components are given. Simulations are done on these designs via PSpice. It is shown that calculations and simulations are supporting each other. After that, a schematicof the circuit has designded and PCB has drawn. With the real circuit, timing tests are done. A 200 kHz PWM is generated from a microcontroller and given to the delay circuits. Results are measured with a high speed-high resolution ossiloscope. In the end, it can be stated that, future of the power electronics lies in superior semiconductors. But since that time, parallel switching method is a good alternative for increasing the efficiency., Yüksek Lisans, M.Sc.

Tez (Yüksek Lisans) -- İstanbul Teknik Üniversitesi, Fen Bilimleri Enstitüsü, 2014, Thesis (M.Sc.) -- İstanbul Technical University, Institute of Science and Technology, 2014, Bu çalışmada poli(dimetilsiloksan) (PDMS) katkısının polietilen (PE) harman nanokompozitlerinin morfolojik, termal, yapısal ve mekanik özelliklerine olan etkisi incelenmiştir. Değişik oranlarda alçak yoğunluklu polietilen/metalosen polietilen (AYPE/m-PE) harman matrisli örnekler 27 mm çapında, L/D'si 48 olan çift vidalı ekstrüder ile eriyik karıştırma yöntemiyle hazırlanmıştır. Çalışma sıcaklığı 70-205°C aralığında belirlenmiştir. Onyum iyonlarıyla modifiye edilmiş organokil (Nanomer® I.44P) harmanlara yüzde 5 oranında ilave edilmiştir. Polietilen harmanları ile nanokil arasındaki uyumu sağlamak amacıyla yüzde 15 maleik anhidrit aşılanmış polietilen eklenmiştir. Bunlara ilaveten nanokompozit özelliklerine etkisini araştırmak amacıyla örneklere yüzde 5 ve 10 PDMS katılmıştır. Örneklerin morfolojik, termal, yapısal ve mekanik özellikleri incelenmiştir. Örneklerin gerçek dolgu miktarı kül testi ile belirlenmiştir. XRD sonuçları tabakaları kısmen dağılmış yapılar elde edildiğini göstermiştir. DSC sonuçlarına göre örneklerin kristallenme dereceleri (Xc) artan PDMS miktarı ile azalmaktadır. Bu durum AYPE zengin nanokompozitlerde daha belirgin olarak gözlenmektedir. Tüm örneklerde yüzde 5 ve 10 PDMS ilavesi ile temas açısı değerlerinin sırasıyla %15-20 ile %25-30 arttığı gözlenmiştir. Örneklerin çekme-kopma testleri, Izod darbe dayanımı ve sertlik testlerinin sonuçları PDMS ilavesinin nanokompozitlerin mekanik özelliklerinin önemli ölçüde etkilendiğini ortaya koymuştur., In this study, the effects of the poly(dimethylsiloxane) (PDMS) to the polyethylene (PE) blends nanocomposites were investigated morphologically, thermally, structurally and mechanically. The low density PE/metallocene PE (LDPE/m-PE) blends samples with different compositions were prepared as matrix PE by melt mixing method using co-rotating twin screw extruder with L/D ratio of 48. Processing temperatures were taken between 70-205°C. Onium ions modified organoclay (Nanomer® I.44P) were added as 5 phr to the blends. In order to obtain the compatilibility between polyethylene blends and nanoclay layers, 15 phr maleic anhydride grafted polyethylene was used. In addition to these, 5 and 10 phr PDMS was added to the samples to investigate the effects of PDMS to the properties nanocomposites. Morphological, thermal, structural and mechanical properties of the samples were investigated. Actual filler contents of the samples were determined by ash content tests. XRD results showed that structures between intercalated/exfoliated were obtained. According to DSC analysis, it was observed that degree of crystallinities (Xc) of the samples were decreasing with the increasing amounts of PDMS and this situation is more significant in LDPE rich samples. In all samples, with the addition of 5 and 10 phr PDMS to the clay containing nanocomposites, PDMS increased the contact angle values around 15-20% and 25-30%, respectively. Mechanical characterization results by tensile, Izod impact strength and hardness tests, revealed that the addition of PDMS to the nanocomposites had affected the mechanical properties significantly., Yüksek Lisans, M.Sc.

Hintergrund Jede Implantation alloplastischer Materialien führt durch Aktivierung der körpereigenen Immunabwehr zu einer Fremdkörperreaktion. An der Synthese der Extrazellulärmatrix und der entstehenden Kollagenkapsel sind insbesondere Makrophagen und Fibroblasten beteiligt. Diese Reaktionen können die Material-Funktionsfähigkeit abschwächen, aufheben oder zu deren operativer Entfernung zwingen. Fragestellung und Ziele Spinnenseide ist ein Material mit hoher Biokompatibilität. Nachdem es gelungen ist, Spinnenseide rekombinant herzustellen, soll untersucht werden, wie sich die Verträglichkeit alloplastischer Materialien durch eine Beschichtung mit biotechnologisch hergestellter Spinnenseide beeinflussen lässt. Eine weitere Möglichkeit ist der TGF-β-Synthese-Inhibitor Halofuginon, der ebenfalls hinsichtlich seiner Potenz, die Ausbildung einer Fibrosekapsel zu vermindern, untersucht werden soll. Methodik Anhand von in-vitro-Untersuchungen wurden die bei der Fremdkörperreaktion beteiligten Zelltypen auf ihr Proliferationsverhalten und die Expression unterschiedlicher Genprodukte hinsichtlich bestehender Unterschiede zwischen den jeweiligen Oberflächenbeschichtungen untersucht. Es wurden immunhistochemische Färbungen zum Nachweis spezifischer Oberflächenantigene, Bestimmungen von ATP- und DNA-Gehalt als Maß für die Zellzahl, sowie molekulargenetische Untersuchungen hinsichtlich der Expression relevanter Markergene (rtPCR) durchgeführt. Ergebnisse Eine Beschichtung mit rekombinanter Spinnseide führt - im Vergleich zu reinen Silikonimplantaten - zu einer verzögerten und reduzierten Immunreaktion. Die EZM-Synthese und die damit verbundene fremdkörperassoziierte Fibrose werden vermindert und so die Biokompatibilität alloplastischer Materialien gesteigert., Introduction: Optimisation of the biocompatibility of silicone implants and reduction of capsule formaiton around the surface of such implants are in the focus of plastic surgical biomaterial research. In addition to its extraordinary physical and biochemical properties, spider silk shows high biocompatibility. Therefore, the coating of silicone implant surfaces with recombinant spider silk wwas analysed regarding foreign body reactions. Another possibility to modify the surface is a coating with chinazolinone derivative halofuginone which is a type I collagen synthesis inhibitor that interferes with the TGF-beta signaling pathway. Methods: We compared proliferation and expression of different gene products in-vitro by immunhistochemistry, content of ATP and DNA, and rtPCR. Conclusion: The results confirmed a decrease in foreign body responses to spider silk or halofuginone surface-modified silicone implants and mark their potential for obtaining a lessened capsular fibrosis by way of a local antifibrotic effect.

It is possible to say that the structures, which materials are used with nominative in today’s technology, repeat themselves in variety of structure. Concrete mass which are exposed the holes of bolt mold, metal surfaces which are protected of view oxidized, wood plaques impregnated for avoid only the conditions of outdoor are frequently used in architecture, either indoor or outdoor, due to their natural appearances. The designers, who adopted the approach of using materials in their natural states, tend to make difference in about structures in this repetition and try several technics. Approaches of usage by giving texture or forming pattern to surfaces of materials of concrete, plaster, etc., which are used pouring into molds pre-prepared, can give an example for those technics. It’s necessary to shear or contuse the certain regions of concrete surface to create pattern and texture on concrete out of the mold, and these operations create loss of time and energy in implementation process. Another method of forming pattern and texture on concrete surface is to use the special-designed molds in casting process. It is taken a mold by forming model with the materials like clay, mud, plastilin, which can be shaped easily and pouring concrete to these molds, intended texture on the surface of concrete out of the mold is obtained. In this study, different methods about the forming texture on the surface of concrete are obtained, starting from the traditional molding stage to silicone mold technology. Production method and process of texture, which are become different from standard operations and can be premeditated for the texture obtained are examined with positive and negative sides as main subject of the study. Keywords: Texture, Silicone, Molding, Casting, Interior

Meine Arbeit umfasst hauptsächlich zwei Teile, eines ist GNA als Gerüst für molekülare Aggregaten von Chromophoren, das andere ist das Design der oktaedrischen Silicium-Komplexe als DNA Bindemitteln. Im ersten Teil meiner Arbeit wurde die vereinfachte Glykol Nukleinsäure (GNA) als Template für die spiralförmige Anordnung von kovalent gebundenen homochromophoren und heterochromophoren (Perylenbisimide (B), Phthalocyanine (Y) und Porphyrine (P)) verwendet. Unterschiedliche Anzahlen von Chromophoren konnten sich innerhalb des Duplexes stapeln, und daduch die künstliche Doppelhelix-Strukturen mit modifizierten Funktionen zu schaffen. Im zweiten Teil der Arbeit wurden die ersten Beispiele für biologisch aktive Komplexe, basierend auf oktaedrisch coordiniertem Silizium mit arenediol und phenazinediol Liganden, entwickelt. Solche Silicium-Komplexe können verwendet werden, um mit DNA-Duplexe zu interkalieren, falsch eingeordnete DNA-Basenpaare zu erkennen, und die Bildung des G-Quadruplexs zu stabilisieren., My work mainly includes two parts, one is GNA as a scaffold for molecular aggregates of chromophores, and the other one is the design of octahedral silicon complexes as DNA binders. In the first part of the thesis, simplified glycol nucleic acid (GNA) was used as the template for the helical assembly of covalently bound homochromophores and heterochromophores: perylene bisimide (B), phthalocyanine (Y), and porphyrin (P), and different numbers of chromophores could be stacking inside a duplex which led to functional artificial double-helical structures. In the second part of the thesis, the first examples of biologically active complexes based on octahedral silicon were designed, and silicon complexes with simple arenediol ligands and phenazinediol ligands were successfully synthesized. These kinds of siliconcomplexes could be used to intercalate with DNA duplexes, detect mismatched DNA base pairs, and stabilize the formation of the G- quadruplex.

Silikonprodukte werden erfolgreich im klinischen Alltag eingesetzt und haben sich in vielen Bereichen der Medizin als nützlich erwiesen. Trotz guter Biokompatibilität ist die Verwendung von medizinischen Materialien aus Silikon, besonders bei der dauerhaften Integration in den Körper, mit Komplikationen verbunden. Die Brustrekonstruktion mit Silikonimplantaten ist ein Beispiel für den langfristigen Gewebeersatz mit einem Fremdmaterial. Der Organismus erkennt dabei das synthetische Polymer und reagiert mit einer fibrösen Abkapselung. Dabei handelt es sich um eine physiologische Entzündungsreaktion mit Abgrenzung des Implantats durch Bestandteile der extrazellulären Matrix. Durch bisher nicht vollständig geklärte pathophysiologische Abläufe kann es jedoch zu einer verstärkten Ausprägung dieser Kapselfibrose kommen, was mit Schmerzen und einer Deformierung sowie Zerstörung des Implantats einhergehen kann. Als Konsequenz einer voll ausgeprägten Kapselfibrose, der sogenannten Kapselkontraktur, bleibt dann meist nur eine operative Revision. Das Ziel dieser Arbeit war die Modifizierung herkömmlicher Silikonimplantate, um die Biokompatibilität zu verbessern und die übermäßige Ausbildung einer periprothetischen Kapsel als häufigste revisionsbedürftige Komplikation zu vermeiden. Dafür wurde der antifibrotische Wirkstoff Halofuginon in einem nasschemischen Beschichtungsprozess auf eine Silikonoberfläche gebunden und die Implantate in einem Tiermodell der Ratte untersucht. Es zeigte sich, dass Halofuginon den TGF-beta1-Signalweg durch Beeinflussung der intrazellulären Smad-Signalkaskade hemmt, wodurch es unter anderem zu einer spezifischen Hemmung der Kollagen-Typ-I-Expression kommt. Histologische, immunhistologische und molekularbiologische Untersuchungen nach einer Implantationsdauer von drei Monaten zeigten, dass eine Halofuginonbeschichtung die Kollagendichte, die Kapseldicke und die Anzahl an Fibroblasten und Entzündungszellen im Kapselgewebe vermindert. Zusätzlich konnten weniger TGF-beta- und CD68-positive Zellen im Vergleich zur Kontrollgruppe nachgewiesen werden. Die Ergebnisse der Real-Time-PCR zeigten übereinstimmend eine erniedrigte Expression für TGF-beta1, Kollagen-Typ-I, CTGF und CD68 und bestätigten die immunhistologische Auswertung. Darüber hinaus konnte eine verminderte Expression des MMP-2-Gens nachgewiesen werden, welches für die Steuerung der EZM-Ablagerung mitverantwortlich ist. Es kann belegt werden, dass eine Halofuginon freisetzende Silikonhybridoberfläche effektiv und spezifisch die pathologische periprothetische Kapselbildung hemmt. Es sind jedoch weitere in-vivo-Studien zur Überprüfung der Nachhaltigkeit und der Pharmakodynamik erforderlich, um die gewonnenen Erkenntnisse als Schritt in der Verbesserung der Biokompatibilität von Silikonimplantaten nutzen zu können., Modified medical silicone implants in surgery - in vivo compatibility of Polydimethylsiloxan-Tetraethoxysilan-Halofuginone-Surfaces

Arbetet har utförts i samarbete med Naturskyddsföreningen för att undersöka vilka vattenavvisande behandlingar som görs på ytterplagg för barn och hur tillverkarna förhåller sig till perfluorerade ämnen. I arbetet har vattenavvisande ytterplagg för barn i förskoleåldern studerats, med syfte att se i vilken mån perfluorerade ämnen används i plaggen. Barnen som har studerats är utomhus varje dag i alla väder. Vid kraftigt regn eller när det är mycket blött ute används vattentäta regnställ, vid lättare väta bär de ytterplagg med vattenavvisande funktion. En egen oljedropptestmetod har utvecklats. Testet har utförts på de plagg som hänger på förskolorna. Det finns flera typer av vattenavvisande behandlingar. De vanligaste är perfluorerade ämnen, silikoner, dendrimerer och vaxer. De har olika egenskaper och funktioner sinsemellan. De perfluorerade ämnena har den bästa vattenavvisande förmågan och de är också de enda som är oljeavvisande. Perfluorerade ämnen är persistenta, bioackumulerande, hormonstörande och toxiska. Hormonstörande ämnen kan bidra till fetma, cancer, neurologiska störningar, fortplantningsstörningar och missbildningar. Silikoner har goda vattenavvisande egenskaper. Råvaran till silikoner är persistent, bioackumulerande och toxisk. Även dendrimerer har goda vattenavvisande egenskaper. Lite är känt om miljö- och hälsopåverkan men partiklar i nanostorlek kan potentiellt ta sig in cellerna och orsaka cancer. Inga allvarligare miljö- och hälsokonsekvenser av vaxer/paraffiner har hittats. De har sämre vattenavvisande egenskaper, påverkar greppet och tål tvätt och nötning dåligt. De kläder som används på förskolorna håller generellt barnen torra, men en försämring kan märkas på gamla eller dåligt konstruerade plagg. Ytterplagg som behandlats med perfluorerade ämnen är vanliga. Företagen har fasat ut perfluorerade ämnen under de senaste åren, planerar att byta ut dem eller har vidtagit åtgärder enligt Reach. Dendrimerer är det vanligaste alternativet till perfluorerade ämnen. Inga krav förekommer från vare sig företag eller användare på att plaggen ska vara smuts- och oljeavvisande. Program: Textilingenjörsutbildningen

Bitim işlemleri, tekstil terbiye proseslerinin son basamağını oluşturan ve mamulün kullanım, tutum ve görünüm özelliklerini etkileyen ve yeni özellikler kazandıran işlemlerdir. Bitim işlemleri prosesi, materyal için kullanılan bitim işlemleri maddeleri ve kimyasal yapıları, bitim işlemleri reçetelerinde kullanılan yardımcı malzemeler, bitim işlemi çözeltisinin pH’ı, bitim işleminin uygulandığı makine, kumaşın renklendirme durumu ve boyama reçetesi, uygulama sonrası kurutma ve kondense işlemleri gibi parametrelerin bütünüdür. En önemli parametreyi ise bitim işlemi için kullanılan madde miktarı ve bitim işlemi cinsi oluşturmaktadır. Denemelerde bitim işlemi maddeleri olarak, katyonik yapıdaki yumuşatıcı ve silikon emülsiyonu kullanılmıştır. Bu makalede, pamuklu kumaştaki bitim işlemleri performansının değerlendirilmesinde bitim işlemleri maddelerinin miktarlarının, bitim işlemleri reçetesinin uygulandığı pH aralıklarının ve kurutma sıcaklıklarının etkisi incelenmiş ve bunların kumaşın haslık değerlerine etki edip etmediği gözlemlenmeye çalışılmıştır. Ayrıca bitim işlemi maddesi olarak kullanılan yumuşatıcı ve silikonun birlikte ve ayrı ayrı kullanılmasının da bitim işlemi performansına etki edip etmediği araştırılmaya çalışılmıştır. Chemical finish are the processes which compose the last step of the textile finishing processes and they affect the usage, handle and appearance properties of the product and these processes bring new properties to the product. The process of chemical finish is the integration of parameters such as, chemical finish substances and cehmical structures used fort thematerial, subsidiary subtances used in chemical finish prescriptions, the pH of chemical finish solution, the machine through which chemical finish is applied, the colouration status of the fabric, and painting prescription, the condensation and draining treatment safter the application. The most important parameter is the chemical finish amount and chemical finish type. In tests, cationic conditioner and silicone emulsion are used as chemical finish substances. In this article, the effect of the chemical finish amounts, the pH ranges in which chemical prescription is applied, and the draining temperatures and it has been attempted to research if the chemical finish performance is affected, or not when the conditioner and silicone are used separately as chemical finish substances andwhen they are used together.

The aim of this work is an experimental microscale comparison of several imperfection types of silicon solar cells which emit visible light under reverse bias condition. The setup with scanning probe microscope (SPM) and sensitive detector is used for the measurement of light emission in microscale. Used SPM allows a measurement of Light Beam Induced Current (LBIC) with high spatial resolution together with sample topography. Due to a number of observed defects that have no correlation with surface topography, we have found out that there are also defects having strong correlation with surface topography. In the most cases, investigated inhomogeneites could not be localized via light induced beam technique.

[no abstract]

The Thesis deals with the development of new concepts for improving the properties of natural and synthetic textile fibres. A natural fibre, cotton, has been chosen as fibrous material. The focus of the modification has been directed towards its handle properties, which usually are improved at the expense of moisture up-take. The silicon based compounds were used for this work. Polylactic acid and polypropylene have been chosen as synthetic fibres whose textile potential is hindered by their poor dyeability and low moisture sorption capacity and which can be modified at spinning stage with suitable additives. The focus here has been directed on using recyclable natural materials as additives for achieving an improved comfort property of the synthetic polymer. Two chemical processes, namely coating and infiltration, were considered for applying functional polymers on the fibre surface and, respectively, for modifying the bulk of a polymer via infiltration of particles into the matrix. The coating of cotton with two hydrophilic silicon softeners, a silanol compound and a PDMS compound, was carried out from water, as a classical method, and from supercritical CO2, respectively, as a new approach. The coating process and the change of the fabric properties were investigated by using Scanning Electron Microscopy (SEM), elemental identification Energy Dispersive X–Ray Spectroscopy (EDX), Fourier Transform Infra-Red Spectroscopy (FTIR), X-Ray Photoelectron Spectroscopy (XPS), moisture analyser and Kawabata Evaluation System (KES-FB). The results allowed optimising the route of silicon product application and put into evidence the benefits of the treatment, independently of the fabric structure. The polylactic acid and polypropylene based composites were produced via melt infiltration of powders of chitosan, cotton or keratins into polymer matrix. The prepared powders were characterised using FTIR, NMR, Raman microscopy and amino acid analysis. The distribution of the powders into the matrix was investigated by SEM analysis. The composites show good thermal and mechanical properties demonstrated by Differential Scanning Calorimetry (DSC) and Thermogravimetric Analysis (TGA) and miniature material tester (MiniMat2000). The ability of absorbing and keeping the moisture was highly improved for all materials, as shown with IGA sorb moisture analyser. Polylactic acid based composites proved also an improved ability for dyeing with reactive and acid dyes at 100°C. Summing up the fibres properties can be controllable improved by selecting the appropriate synthetic polymer structure for coating natural fibres, or the appropriate natural additive for infiltrating the matrix of the synthetic fibre.

This paper discusses configuration of thin-film photovoltaic cells, which are one of the new trends in the sphere of solar system. The first part of the paper is very shortly introduction to problematic of the Sun energy and its utilization in the sphere of photovoltaic. The basic information of the Sun, its energy, the photovoltaic effect and the photovoltaic cells are presented here. Problematic of the thinfilm photovoltaic is analyzed in the second part. At the beginning of this part term “thin film” is defined. Then three basic configurations of the thin-film cells (superstrate, substrate and tandem) are distinguished. Principle, sequences of thin layer and materials two of these configurations are briefly mentioned in this part among others.

Problems of the photovoltaic cells becomes more and more topical in connection with sharply rising prices of the electrical energy and thus the new technology of solar cells produce are invented. This paper is focused on problematic of one of the new trends in the photovoltaic cells sphere – on the Sliver technology. This is the monocrystalline silicon technology which reduce the silicon usage and thereby the cost of the photovoltaic cells. The technology could have decreasing the silicon feedstock requirements to 1 tonne per MW. On top Sliver cells are great at high performances characteristic, e.g. high efficiency, high open circuit voltage, near lambertian light trapping, very good tolerance of varying material quality, etc. The first part of this paper is dedicated to the Sliver technology generally. The concept of the Sliver photovoltaic cells, texturing method, most important Sliver cell design and IV curve are presented here among others. In the second part I deal with the Sliver modules. There are described the principle of the modules, most important performance, e.g. low operation temperature, low temperature coefficient, high energy yield, light high performance, etc.

In der Arbeit wird eine elastische Linse variabler Brenn­weite entwickelt. Es ergibt sich aus einer analy­tischen Untersuchung das Konzept einer Kompositlinse mit einem weichen Kern. Über Kerngeometrie und -steifigkeit kann das Deformationsverhalten angepasst werden. Eine Finite-Elemente-Optimierung der Kernparameter minimiert die Abweichungen von der Sphärenform. Die optimierten Kompositlinsen erreichen in der Simulation auf dem ganzen abgedeckten Brechkraftbereich die optischen Eigenschaften von sphärischen Referenzlinsen.

Kemijska stabilnost i indiferentnost čine silikon biokompatibilnim, pogodnim i neškod1jivim za produljeni kontakt sa živim organizmom. Susrećemo ga u komercijalno dostupnim silikonskim ortozama čiji je oblik definiran na bazi prosjeka i optimizacije velikog broja uzoraka. Izrada individualnog ortopedskog pomagala od silikona predstavlja složeno tehničko pitanje. Nakon digitalizacije plantarne površine stopala, napravljen je dizajn uložaka te su kreirane putanje alata numeričke glodalice. Silikonski ortopedski ulošci su dobiveni direktnom obradom silikonskog bloka, te postupkom izravnog gumarskog prešanja nakon izrade metalnih kalupa na stroju. Potonji postupak pokazao se boljom metodom za proizvodnju navedenog tipa uložaka.

As well as increasing a bonded joint's resistance to ageing and chemicals, adhesion promoters can also strengthen the bond and extend the service life of an activated surface. Normally adhesion promoters are applied following a surface treatment. For high quality pre-treatments, plasma processes are frequently used. Plasma processes at atmospheric pressure have a number of specific advantages, including the option of in-line treatment, high treatment speeds and the possibility of site-specific treatment. The Fraunhofer Institute for Manufacturing Technology and Applied Materials Research (IFAM) in Bremen studied the deposition of adhesion-promoting layers using plasma at atmospheric pressure. The coating is produced by plasma polymerisation of silicon organic molecules. A plasma source from Plasmatreat GmbH, which was modified at the Fraunhofer IFAM to allow for layer deposition, was used for plasma coating at atmospheric pressure. The adhesion-promoting effect of this coating was investigated by depositing the plasma polymer on two aluminium alloys: 6016 (not anodised) and AlMgSi3. After this the samples were bonded using a heat curing, one-component epoxy adhesive and exposed to a salt spray test. On the untreated samples the bond failed almost completely after the salt spray test. In contrast the plasma-coated samples still retained a lap shear strength of around 15 MPa. Therefore, the adhesion-promoting plasma coating meets the requirement to improve the ageing resistance of a bond in two respects. It increases the bond strength and ensures that the bond between the adhesive and the surface of the substrate is no longer the strength limiting factor. The following assumptions can be made about the function of the plasma polymer based on its adhesion-promoting effect as shown in the results described above: Improvement in the adhesion of the adhesive to the surface resulting from the larger number and increased strength of the adhesive contacts and the Lewis acid-base interactions (for example, covalent bonds). Protection of the substrate surface against corrosion and other damage A change in the degradation mechanism. For example, damaging species are directed by the plasma polymer primarily into the adhesive layer and not onto the surface of the substrate.

Turkish International Cooperation Agency.

In this work, we present two synchronizer groups: the Deterministic Wave Analogue Phase Synchronizer and the Random Symbol Analogue Phase Synchronizer. In the first group, the VCO (Voltage Controlled Oscillator) synchronizes with the expected phase of the input deterministic wave and in the second group, the VCO synchronizes with the unexpected phase of the input random symbols. In each group, we present two topologies which are the analog (full-analogue) and the hybrid (semi-analogue). Our main objective is to study the two groups of synchronizers with its two topologies and to observe its jitter behavior as function of the noise.

Aufgrund der begrenzten Spenderverf gbarkeit und m glichen Komplikationen, die mit einer Autograft-Transplantation auftreten k nnten, werden Xenografts und Allografts als Alternativen in vielen chirurgischen Anwendungen als osteokonduktive Ger ste benutzt. Die Risiken bei der Verwendung von Allografts und Xenografts, Antigenit t und Infektionsgefahr, k nnen durch eine Behandlung mit einem validierten Prozess (hier Tutoplast) verringert werden. Kollagen spielt eine entscheidende Rolle f r die mechanischen Eigenschaften der Bindegewebe, haupts chlich hinsichtlich der Zugfestigkeit [1]. Die Trocknung mit Aceton als L sungsmittel ist einer der Hauptschritte im Prozess. Entsprechend des polymer-in-a-boxMechanismus [2] f hrt die Trocknung zu einer Verringerung der Konfigurationsentropie des Kollagens und infolgedessen zu thermisch stabilerem Kollagen. Die zu pr fende Hypothese ist, dass der Acetonschritt in diesem Prozess zur Verbesserung der thermischen und mechanischen Eigenschaften des Gewebes beitr gt. Tutoplast prozessierte Perikardproben (4 % Wassergehalt), die unter trockenen Bedingungen erhitzt wurden, zeigen keinen signifikanten Anstieg im Anteil an denaturierten Kollagen bis 150 C. Native Proben (80 % Wassergehalt) dagegen stellten sich als empfindlicher heraus und begannen bereits ab 80 C zu denaturieren. Im Gegensatz zur thermischen Behandlung zeigten die Messungen der mechanischen Eigenschaften, Zugfestigkeit und Elastizit tsmodul, so wie der Schrumpftemperatur keinen signifikanten Unterschied zwischen den beiden Gruppen Die Autoren danken der Fa. Tutogen Medical f r die finanzielle Unterst tzung und die Bereitstellung der Materialien.

Techne : Jurnal ilmiah Elektronika ; vol.4, no. 2, Oktober 2005 : 101-106 Bahan semikonduktor Silikon (Si) telah digunakan secara luas dalam pembuatan komponen elektronika termasuk untai terintegrasi. Kelemahan untai terintegrasi dari bahan Si adalah tidak dapat digunakan pada untai logika terapan yang mengolah masukan dengan kecepatan sangat tinggi. Masalah ini diatasi dengan menggunakan Gallium Arsenide (GaAs) sebagai bahan alternatif untai terintegrasi menggantikan Si.

Günümüzde elastan (lycra®) içeren dokuma kumaşlardan yapılan giysilere talep oldukça fazladır. Elastanlı kumaşın rahatlığı, vücuda uyumu, esnekliği onu aranan ürün haline getirmiştir. Bu araştırmada; tekstil endüstrisinin son yıllarda en önemli konularından biri olan, konfeksiyon sanayiinde elastan (lycra®) içeren dokuma kumaşların dikiş problemleri incelenmeye çalışılmıştır. Elastan (lycra®) içeren dokuma kumaşın, dikiş problemlerini inceleyebilmek için elastanlı kumaşın oluşum aşamalarını çok iyi takip etmek ve kumaşın özelliklerini ortaya çıkarmak gerekir. Bu amaçla, bu araştırmada, elastan oranları % 3-4 arasında değişen, farklı özelliklerde elastanlı dokuma kumaş numuneleri dokutulmuştur. Bu kumaş numunelerinde; elastan çekim oranının, ön fikse sıcaklığının, silikonlu aprenin, kumaş sıklığının, örgü tipinin, elastanlı iplik tipinin ve elastanlı iplik üzerindeki punta sayısının dikiş performansı ve dikiş problemleri üzerindeki etkisi incelenmiştir. Dikiş performansının belirlenmesinde etkili olan değerler, kopma mukavemeti ve uzaması, kalıcı uzama ve kumaş elastikliği (growth), yırtılma mukavemeti, dikiş mukavemeti, dikiş yeterliliği ve iğne dalış kuvvetidir. Dikiş problemleri olarak, dikiş kayması, dikiş sırıtması ve dikiş hasarları incelenmiştir. Elastanlı dokuma kumaşlarda en fazla dikiş probleminin dikiş hasarlarından ortaya çıktığı görülmüştür. Elastanlı kumaşların kopma dayanımları düşük hasara karşı eğilimleri yüksektir. Elastan içeren dokuma kumaşların dikiş problemleri ve dikilebilirlik değerleri objektif olarak ortaya çıkarılmış, kumaş özellikleri ile dikilebilirlik göstergeleri arasında lineer korelasyonlar elde edilmiştir. In todays world, there is significant demand to elastic woven stretch fabrics. Garments made from elastic woven stretch fabrics allow easy body movements, fit well, keep their shape and they are comfortable to wear. Elastane has now become a standard fiber in all areas of clothing. In clothing industry, the sewing problems of elastic woven fabrics are very important. In order to be able to observe the sewing problems of elastic fabrics, the production step of fabrics should be followed carefully and fabrics specifications needs to be determined precisely. In this study, 3 fabric types were woven with different specifications for the experiments. Elastane ratio was taken % 3-4 in those fabrics. This study presents an experimental study about the effects of elastane draw ratio, pre- fixation temperature, silicone, fabric structure and elastane yarn structure to the sewing performance and sewing problems. Breaking strength, breaking strain, residual extension, tear strength, seam strength, seam openning strength, seam efficiency and needle penetration forces were important factors for sewing performance. There are two basic problems in the seam operation of the elastic fabrics. One of them is unsufficient elasticity of the seams and the other is elastane damage. In woven stretch fabrics the major sewing problems occur due to the sewing damage. Those fabrics have low breaking strength and tendency to sewing damage. At the end of the experimental study, relations between sewability and fabric properties were determined. Saydam Tekstil A.Ş. Gürdere Tekstil A.Ş. Berke Tekstil A.Ş. Periot Tekstil A.Ş. Technicare Services Limited (İngiltere) Gebze-TÜBİTAK Marmara Araştırma Merkezi

Einleitung: Die aktuellen Techniken der freien Lappentransplantation mit mikrovaskulärer Anastomose haben bekannte Nachteile durch die Begrenzung der verfügbaren Spenderareale, den teilweisen Funktionsverlust und ggf. die Deformierung dieser Areale. Häufig entstehen weitere Nachteile im Empfängerareal dadurch, dass Farbe, Kaliber oder Hauttyp einer optimalen Rekonstruktion entgegenstehen. Die Präformierung eines Gewebelappens durch die Implantation eines versorgenden Gefäßträgers macht es möglich, Lappen zu entwickeln, welche einen Teil der o.g. Limitierungen vermeiden. Für die optimale Anlage solcher Lappen ist eine verbesserte Kenntnis der Mechanismen der im Lappen stattfindenden Neovaskularisation von zentraler Bedeutung Material und Methoden: Am tierexperimentellen Modell des Kaninchens wird ein Bauchhautlappen der Größe 8 x 15 cm mit lateraler Basis angelegt und mit einer Gefäßschlinge (« Loop ») gestielt, die aus der mit der V.Femoralis anastomosierten A. Femoralis / A. Saphena besteht. Der Einfluß einer implantierten Silikonfolie auf Ausmaß und Geschwindigkeit der Neovaskularisation im Lappen wird durch den Vergleich von 2 Versuchsgruppen mit einer Kontrollgruppe bestimmt: Gruppe 1, 30 Tiere ohne Silikonimplantat, Gruppe 2, 28 Tiere mit Silikonimplantat auf der Bauchwandfaszie, Kontrollgruppe, 4 nicht operierte Tiere. Je 6 Tiere einer Versuchsgruppe werden nach 4, 8, 12, 16 und 20 Tagen post-OP sowohl durch selektive Mikroangiographie, als auch durch histologische und makroskopische Befundung in Hinsicht auf die zu diesem Zeitpunkt erfolgte Neovaskularisation untersucht und an Hand der Kontrollgruppe bewertet. Ergebnis: Die Silikonfolie (Gruppe 2) induzierte von Tag 4 post OP an eine zu allen Untersuchungszeitpunkten signifikant ausgedehntere und schnellere Neovaskularisation im Lappen als in der Vergleichsgruppe (p≤0,05), 20 Tage post OP unterschieden sich beide Gruppen nicht mehr signifikant von der nicht operierten Kontrollgruppe (p≤0,05). Schlußfolgerung: Auf Grund der genannten Ergebnisse läßt sich für das Tiermodell sagen, daß im präformierten Lappen die Neovaskularisation nach Implantation einer Silikonfolie signifikant (p≤0,05) schneller abläuft und zu größerer Maximalperfusion führt als in der Vergleichsgruppe ohne Silikon. Damit scheint die Silikonimplantation eine vielversprechende Möglichkeit zur Optimierung der Gefäßversorgung eines präformierten Gewebelappens zu sein. Introduction: Current techniques of free flap transplantation with microvascular anastomosis have the disadvantages of limitation of available donor sites, loss of donor site function, and the possibility of of donor site defect or deformity. Furthermore standart free flaps often have the disadvantage of beiing not adaptable to the demands of difficult reconstructions (e.g. face or distal limbs) due to their caliber, colour or skin type. These limitations can be reduced by revascularization of a tissue flap from an implanted pedicle with axial vessels. Better knowledge of the mechanisms of neovascularization is a key to optimized custom-designed flaps. Techniques: Prefabrication of skin flaps by implantation of an axial vascular pedicle based on femoral vessels was developed in a rabbit model. An arteriovenous loop based on the femoral/saphenic vessels was transferred under lateral pedicled 8 x 15 cm panniculocutaneus abdominal flaps. The effects of an flap-underlaying siliconsheeting were studied at different time intervals to determine significant difference in neovascularization: Group 1, 30 rabbits without Silicon-sheeting, Group 2, 28 rabbits with silicon-sheeting, Control-Group, 4 non operated rabbits. At different time intervals (4, 8, 12, 16, 20 days) after prefabrication selective angiography was performed through the vascular pedicle and neovascularisation was measured by counts of perfused vessels in relation to a controlgroup. Results: Siliconsheeting induced after day 4 relatively faster and wider revascularization than the competiting model (p≤0,05); after day 20 a significant difference to the controlgroup was not measurable (p≤0,05). Histological examination provided further visual evidence of the more advanced revascularization in the siliconsheeted model. The mentioned results seem to make the use of siliconsheeting a promising model for prefabrication of vessel-pedicled skin flaps.

Seit Anfang der siebziger Jahre erfolgte die Verwendung von Silikon in der Vorfußprothesenherstellung. Die reine Silikonvorfußprothese wird bei Amputationen im Bereich des Vor- und Mittelfußes seit Mitte der Neunziger Jahre verwendet.Im Rahmen der vorliegenden Arbeit wurde die Funktionalität der reinen Silikonvorfußprothese im Ganglabor sowie die subjektive Beurteilung der Silikonvorfußprothese aus der Sicht von 29 Prothesenträger untersucht. Ferner findet ein Vergleich zur Vorversorgung, zur gesunden Seite sowie teilweise zu einem gesunden Kollektiv statt.Die Ergebnisse im Ganglabor zeigen deutliche Einflüsse auf ganganalytische Parameter, die aus dem Tragen der Silikonvorfußprothese resultieren .Im Vergleich zur Vorversorgung bestehen teilweise signifikante Unterschiede in den einzelnen Punkten.Die subjektive Bewertung der Silikonvorfußprothese ergibt im Mittel eine gute Beurteilung in den Punkten Zufriedenheit, Kosmetik, Tragekomfort und Pflege. From the beginning of the 1970’s silicon has been used fort he manufacture of forefoot protheses. The pure silicon forefoot protheses is used for amputation of the fore- and middlefoot since the middle of the 90`s.The functionality of pure silicone forefoot protheses in the gait laboratory as well as the subjective evaluation as estimated by 29 users is presented here. Further there is a comparison to the previously protheses, to the healthy side of the user and to a healthy collective. The gait laboratory results show clearly the influence of certain parameters, these arising from the use of the prosthesis. Compared to the previously prostheses there are statistical difference in some parameters. The subjective evaluation of the silicon prosthesis gives, on an average, a good result, as far as satisfaction, cosmetic, wearing comfort and care are concerned.

Çeşitli nedenlerle kulak lobülü keloidi oluşmuş hastalarda; cerrahi, postoperatif erken steroid enjeksiyonu ve yine erken dönemde klipsli küpe içerisine yerleştirilmiş silikon jel yaprak uygulamasını kombine ederek kullandık. Çalışmamızda kulak lobülünde keloidi olan 3 hastaya önce eksizyon uygulanmış, postoperatif 7. günde silikon jel yaprak tatbik edilmiş, 14. günde triamsinolon asetonid enjeksiyonu yapılmıştır. Hastaların geç dönem takipleri yapılarak, olgularımızda nüksle karşılaşılmamış, kozmetik sonuçları kabul edilir bulunmuştur., We used a combined therapy that consisted of excision, steroid injection, and application of silicone gel sheet in early postoperative period for the patients having ear lobe keloids. First of all, surgical excision was performed, and then silicone gel sheet placed in clips of earring was applied in the postoperative 7th day, triamcinolon acetonid was injected to the lesion site in the postoperative 14th day. After late postoperative period, we did not encounter recurring of the lesions, and cosmetic results were acceptable.