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| 9. |
- Watanabe, M., et al.
(författare)
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Ex Vivo Generation of Donor Antigen-Specific Immunomodulatory Cells A Comparison Study of Anti-CD80/86 mAbs and CTLA4-lg Costimulatory Blockade
- 2018
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Ingår i: Cell Transplantation. - : SAGE Publications. - 0963-6897 .- 1555-3892. ; 27:11, s. 1692-1704
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Tidskriftsartikel (refereegranskat)abstract
- Adoptive transfer of alloantigen-specific immunomodulatory cells generated ex vivo with anti-CD80/CD86 mAbs (2D10.4/IT2.2) holds promise for operational tolerance after transplantation. However, good manufacturing practice is required to allow widespread clinical application. Belatacept, a clinically approved cytotoxic T-lymphocyte antigen 4-immunoglobulin that also binds CD80/CD86, could be an alternative agent for 2D10.4/IT2.2. With the goal of generating an optimal cell treatment with clinically approved reagents, we evaluated the donor-specific immunomodulatory effects of belatacept- and 2D10.4/IT2.2-generated immunomodulatory cells. Immunomodulatory cells were generated by coculturing responder human peripheral blood mononuclear cells (PBMCs) (50 x 10(6) cells) with irradiated donor PBMCs (20 x 10(6) cells) from eight human leukocyte antigen-mismatched responder-donor pairs in the presence of either 2D10.4/IT2.2 (3 mu g/10(6) cells) or belatacept (40 mu g/10(6) cells). After 14 days of coculture, the frequencies of CD4(+) T cells, CD8(+) T cells, and natural killer cells as well as interferon gamma (IFN-gamma) production in the 2D10.4/IT2.2- and belatacept-treated groups were lower than those in the control group. The percentage of CD19(+) B cells was higher in the 2D10.4/IT2.2- and belatacept-treated groups than in the control group. The frequency of CD4(+)CD25(+)CD127(low)FOXP3(+) T cells increased from 4.1 +/- 1.0% (preculture) to 7.1 +/- 2.6% and 7.3 +/- 2.6% (day 14) in the 2D10.4/IT2.2- and belatacept-treated groups, respectively (p<0.05). Concurrently, delta-2 FOXP3 mRNA expression increased significantly. Compared with cells derived from the no-antibody treated control group, cells generated from both the 2D10.4/IT2.2- and belatacept-treated groups produced lower IFN-gamma and higher interleukin-10 levels in response to donor-antigens, as detected by enzyme-linked immunospot. Most importantly, 2D10.4/IT2.2- and belatacept-generated cells effectively impeded the proliferative responses of freshly isolated responder PBMCs against donor-antigens. Our results indicate that belatacept-generated donor-specific immunomodulatory cells possess comparable phenotypes and immunomodulatory efficacies to those generated with 2D10.4/IT2.2. We suggest that belatacept could be used for ex vivo generation of clinical grade alloantigen-specific immunomodulatory cells for tolerance induction after transplantation.
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| 10. |
- Ahmed, S, 1970, et al.
(författare)
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Fractal-based dual-band small antenna for 2.45 and 5.8 GHz
- 2010
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Ingår i: 21st Micromechanics and Micro systems Europe workshop, 26-29 September 2010, Enschede, The Netherlands. ; , s. 108-111
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Konferensbidrag (refereegranskat)abstract
- Small antennas are becoming important andrequired for many domestic and commercial wireless applications.New design and first experimental results confirmingthe simulations of multi-band patch antenna optimized for the2.45 GHz and 5.8 GHz bands are presented. This design isbased on the practical considerations found for our Minkowski-based fractal antenna that predict the influence ofgeometry modifications on the frequency of operation.
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| 11. |
- Amin, Muhammad, 1979, et al.
(författare)
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Low temperature and cost-effective growth of vertically aligned carbon nanofibers using spin-coated polymer-stabilized palladium nanocatalysts
- 2015
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Ingår i: Science and Technology of Advanced Materials. - : Informa UK Limited. - 1468-6996 .- 1878-5514. ; 16:1
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Tidskriftsartikel (refereegranskat)abstract
- We describe a fast and cost-effective process for the growth of carbon nanofibers (CNFs) at a temperature compatible with complementary metal oxide semiconductor technology, using highly stable polymer-Pd nanohybrid colloidal solutions of palladium catalyst nanoparticles (NPs). Two polymer-Pd nanohybrids, namely poly(lauryl methacrylate)-block-poly((2-acetoacetoxy) ethyl methacrylate)/Pd (LauMA(x)-b-AEMA(y)/Pd) and polyvinylpyrrolidone/Pd were prepared in organic solvents and spin-coated onto silicon substrates. Subsequently, vertically aligned CNFs were grown on these NPs by plasma enhanced chemical vapor deposition at different temperatures. The electrical properties of the grown CNFs were evaluated using an electrochemical method, commonly used for the characterization of supercapacitors. The results show that the polymer-Pd nanohybrid solutions offer the optimum size range of palladium catalyst NPs enabling the growth of CNFs at temperatures as low as 350 degrees C. Furthermore, the CNFs grown at such a low temperature are vertically aligned similar to the CNFs grown at 550 degrees C. Finally the capacitive behavior of these CNFs was similar to that of the CNFs grown at high temperature assuring the same electrical properties thus enabling their usage in different applications such as on-chip capacitors, interconnects, thermal heat sink and energy storage solutions.
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| 12. |
- Brinkfeldt, Klas, et al.
(författare)
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Microshutters for MEMS-based time-of-flight measurements in space
- 2011
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Ingår i: Proceedings of the IEEE International Conference on Micro Electro Mechanical Systems (MEMS). - 1084-6999. - 9781424496327 ; , s. 597-600
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Konferensbidrag (refereegranskat)abstract
- This paper reports on the fabrication, integration and first operation of a mechanical microshutter in a time-of-flight (TOF) based ion detector in space. The microshutter is fabricated from a silicon on insulator (SOI) wafer and operated in a resonance mode, 306 kHz. Open time of the shutter is 100 ns. The microshutters are integrated in the PRIMA instrument, which is part of the payload on the Swedish PRISMA mission. PRISMA was successfully launched into low Earth orbit on June 15, 2010.
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| 13. |
- Campbell, TM, et al.
(författare)
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Respiratory viral infections in otherwise healthy humans with inherited IRF7 deficiency
- 2022
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Ingår i: The Journal of experimental medicine. - : Rockefeller University Press. - 1540-9538 .- 0022-1007. ; 219:7
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Tidskriftsartikel (refereegranskat)abstract
- Autosomal recessive IRF7 deficiency was previously reported in three patients with single critical influenza or COVID-19 pneumonia episodes. The patients’ fibroblasts and plasmacytoid dendritic cells produced no detectable type I and III IFNs, except IFN-β. Having discovered four new patients, we describe the genetic, immunological, and clinical features of seven IRF7-deficient patients from six families and five ancestries. Five were homozygous and two were compound heterozygous for IRF7 variants. Patients typically had one episode of pulmonary viral disease. Age at onset was surprisingly broad, from 6 mo to 50 yr (mean age 29 yr). The respiratory viruses implicated included SARS-CoV-2, influenza virus, respiratory syncytial virus, and adenovirus. Serological analyses indicated previous infections with many common viruses. Cellular analyses revealed strong antiviral immunity and expanded populations of influenza- and SARS-CoV-2–specific memory CD4+ and CD8+ T cells. IRF7-deficient individuals are prone to viral infections of the respiratory tract but are otherwise healthy, potentially due to residual IFN-β and compensatory adaptive immunity.
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| 15. |
- Chang, S, et al.
(författare)
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An electrowetting-based microfluidic platform for magnetic bioassays
- 2010
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Ingår i: The 14th International Conference on Miniaturized Systems for Chemistry and Life Sciences, MicroTAS 2010, 3-7 Oktober, Groningen, Neterlands. - 9781618390622 ; 2, s. 1331-1333
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Konferensbidrag (refereegranskat)abstract
- Here we present our recent work on a droplet-based microfluidic device for manipulating microliter-sized droplets. By replacing the formerly used common dielectric SiO2 with Si3N4 and applying a 33 nm thick Teflon top layer to create a hydrophobic surface, we successfully lowered the actuation voltage from 450 V to 50 Vdc/40 Vac. Sputtered HfO2 with high dielectric constant was also investigated as an insulator, which could reproducibly yield thin defect-free insulation layers and lower the actuation voltage to less than 40 V.
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| 16. |
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| 17. |
- Emadi, A., et al.
(författare)
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Fabrication and characterization of IC-Compatible Linear Variable Optical Filters with application in a micro-spectrometer
- 2010
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Ingår i: Sensors and Actuators, A: Physical. - : Elsevier BV. - 0924-4247. ; 162:2; Sp. Iss. SI, s. 400-405
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Tidskriftsartikel (refereegranskat)abstract
- This paper reports on an IC-Compatible process for the fabrication of Linear Variable Optical Filter (LVOF). The LVOF is integrated with a detector array to result in a micro-spectrometer. The technological challenge in fabrication of an LVOF is fabrication of a well-controlled tapered cavity layer. Very small taper angles, ranging from 0.001 degrees to 0.1 degrees. are fabricated in a resist layer by just one lithography step and a subsequent reflow process. The 3D pattern of resist structures is subsequently transferred into SiO2 by an appropriate etching. Complete LVOF fabrication involves CMOS-compatible deposition of a lower dielectric mirror using a stack of dielectrics on the wafer, tapered layer formation and the deposition of the top dielectric mirror. The design principle, IC-Compatible processing and the characterization results on fabricated LVOFs are presented. (C) 2010 Elsevier B.V. All rights reserved.
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| 19. |
- Enoksson, M, et al.
(författare)
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Human cord blood-derived mast cells are activated by the Nod1 agonist M-TriDAP to release pro-inflammatory cytokines and chemokines
- 2011
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Ingår i: Journal of innate immunity. - : S. Karger AG. - 1662-8128 .- 1662-811X. ; 3:2, s. 142-149
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Tidskriftsartikel (refereegranskat)abstract
- Mast cells are among the first cells of our immune system to encounter exogenous danger. Intracellular receptors such as nucleotide-binding oligomerization domain (Nod) play an important role in responding to invading pathogens. Here, we have investigated the response of human mast cells to the Nod1 ligand M-TriDAP. Human cord blood-derived mast cells (CBMCs) were activated with M-TriDAP alone, or in combination with the Toll-like receptor (TLR) ligands lipopolysaccharide (LPS) and zymosan. Release of pro-inflammatory chemokines and cytokines was measured by ELISA, cytometric bead array and LUMINEX, and degranulation was evaluated by analysis of histamine release. M-TriDAP induced a dose-dependent release of IL-8, MIP-1α, MIP-1β and TNF. In contrast, degranulation could not be observed. When cells were treated with M-TriDAP in combination with the TLR4 agonist LPS, but not with TLR2 agonist zymosan, the secretion of cytokines was augmented. We here present results demonstrating that human CBMCs are stimulated by the Nod1 agonist M-TriDAP alone and in combination with LPS to produce pro-inflammatory cytokines and chemokines. Our results add to the concept that mast cells constitute an important part of our host defense, as they are equipped with several types of important pattern recognition receptors, including TLRs and Nod.
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| 24. |
- Enoksson, SL, et al.
(författare)
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The inflammatory cytokine IL-18 induces self-reactive innate antibody responses regulated by natural killer T cells
- 2011
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Ingår i: Proceedings of the National Academy of Sciences of the United States of America. - : Proceedings of the National Academy of Sciences. - 1091-6490. ; 108:51, s. E1399-E1407
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Tidskriftsartikel (refereegranskat)abstract
- Inflammatory responses initiate rapid production of IL-1 family cytokines, including IL-18. This cytokine is produced at high levels in inflammatory diseases, including allergy and autoimmunity, and is known to induce IgE production in mice. Here we provide evidence that IL-18 is directly coupled to induction of self-reactive IgM and IgG antibody responses and recruitment of innate B2 B cells residing in the marginal zone of the spleen. Moreover, the data suggest that the B-cell activation occurs predominantly in splenic extrafollicular plasma cell foci and is regulated by natural killer T (NKT) cells that prevent formation of mature germinal centers. We also find evidence that NKT cells control this type of B-cell activation via cytotoxicity mediated by both the perforin and CD95/CD178 pathways. Thus, NKT cells regulate innate antibody responses initiated by an inflammatory stimulus, suggesting a general mechanism that regulates B-cell behavior in inflammation and autoreactivity.
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| 25. |
- Enoksson, S, et al.
(författare)
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Various phosphodiesterase subtypes mediate the in vivo antilipolytic effect of insulin on adipose tissue and skeletal muscle in man
- 1998
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Ingår i: Diabetologia. - : Springer Science and Business Media LLC. - 1432-0428 .- 0012-186X. ; 41:5, s. 560-568
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Tidskriftsartikel (refereegranskat)abstract
- The antilipolytic effect of insulin on human abdominal subcutaneous adipose tissue and skeletal muscle during local inhibition of cAMP-phosphodiesterases (PDEs) was investigated in vivo, by combining microdialysis with a euglycaemic, hyperinsulinaemic clamp. During hyperinsulinaemia, the glycerol concentration decreased by 40% in fat and by 33% in muscle. Addition of the selective PDE3-inhibitor amrinone abolished the insulin-induced decrease in adipose glycerol concentration, but did not influence the glycerol concentration in skeletal muscle. Nor did the PDE4-selective inhibitor rolipram or the PDE5-selective inhibitor dipyridamole influence the insulin-induced decrease in muscle tissue glycerol. However, the non-selective PDE-inhibitor theophylline counteracted the antilipolytic action of insulin at both sites. The specific activity of PDEs was also determined in both tissues. PDE3-activity was 36.8+/-6.4 pmol x min(-1) x mg(-1) in adipose tissue and 3.9+/-0.5 pmol x min(-1) x mg(-1) in muscle. PDE4-activity in skeletal muscle was high, i.e., 60.7+/-10.2 pmol x min(-1) x mg(-1) but 8.5 pmol x min(-1) x mg(-1) or less in adipose tissue. In conclusion, insulin inhibits lipolysis in adipose tissue and skeletal muscle by activation of different PDEs, suggesting a unique metabolic role of muscle lipolysis.
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| 29. |
- Hagstrom-Toft, E, et al.
(författare)
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Marked heterogeneity of human skeletal muscle lipolysis at rest
- 2002
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Ingår i: Diabetes. - : American Diabetes Association. - 0012-1797 .- 1939-327X. ; 51:12, s. 3376-3383
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Tidskriftsartikel (refereegranskat)abstract
- In this study, variations in lipolysis among different muscle groups were examined by measuring local net glycerol release in vivo in healthy, normal-weight subjects (n = 11) during rested, postabsorptive conditions. Microdialysis of the gastrocnemius, deltoid, and vastus lateralis muscle regions revealed that extracellular glycerol concentrations of these three muscle regions were 84.7 ± 6.7, 59.7 + 7.3, and 56.4 ± 7.5 μmol/l, respectively, and the arterial plasma glycerol concentration was 44.8 ± 2.3 μmol/l (P = 0.0003–0.006, gastrocnemius vs. others). Local tissue blood flow, as measured by Xe clearance, did not differ among the regions. Net glycerol release was significantly higher in gastrocnemius muscle than in the two other regions. There were no regional differences in glycerol uptake when studied during glycerol infusion. Gastrocnemius muscle showed a dominance of type 1 fibers (70%), whereas the vastus lateralis muscle had equal distribution of fiber types (P = 0.02). No differences in intramuscular triaclyceride content, perimuscular fat, or the adipocyte-specific protein perilipin were observed among the muscle regions. Triglyceride turnover in the gastrocnemius muscle was 3.3 + 1.4% over 24 h, which is about 10 times more rapid than the turnover rate in subcutaneous adipose tissue (P < 0.01). Thus there were marked differences in lipolytic activity among skeletal muscle groups at rest, possibly reflecting variations in fiber type.
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| 31. |
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| 32. |
- Hamrin, Kerstin, et al.
(författare)
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Prolonged Exercise-Induced Stimulation of Skeletal Muscle Glucose Uptake Is due to Sustained Increases in Tissue Perfusion and Fractional Glucose Extraction
- 2011
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Ingår i: Journal of Clinical Endocrinology and Metabolism. - : The Endocrine Society. - 0021-972X .- 1945-7197. ; 96:4, s. 1085-1092
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Tidskriftsartikel (refereegranskat)abstract
- Context: The mechanisms behind the positive effects of physical activity on glucose metabolism in skeletal muscle and the time course of the effects need to be more elucidated. Objective: The aim was to examine the prolonged effects of an acute bout of one-legged exercise on local skeletal muscle glucose utilization and tissue perfusion. Design and Setting: Interstitial glucose concentration, local tissue perfusion, glucose uptake, and effects of insulin infusion were studied 12 h after an acute bout of exercise and without prior exercise. Participants: Ten healthy subjects, five women and five men, participated in the study. Intervention: Microdialysis measurements, (133)Xe clearance, and a 2-h hyperinsulinemic euglycemic clamp were performed on two occasions. Main Outcome Measures: We measured interstitial glucose concentration and tissue perfusion in the quadriceps femoris muscle of both legs. Results: Tissue perfusion (3.3 +/- 0.6 ml x 100 g(-1) x min(-1) vs. 1.4 +/- 0.2 ml x 100 g(-1) x min(-1); P = 0.007) and basal glucose uptake (2.3 +/- 0.5 mu mol x 100 g(-1) x min(-1) vs. 0.9 +/- 0.2 mu mol x 100 g(-1) x min(-1); P = 0.006) were increased in the leg that had exercised compared to the resting leg; the findings in the resting leg were comparable to those in the control experiment without prior exercise. The relative effect of insulin on fractional skeletal muscle glucose uptake was the same in all experimental settings, and insulin did not affect tissue perfusion. Conclusions: The prolonged stimulatory effect of physical exercise on skeletal muscle glucose uptake was mediated via vascular effects combined with an increase in basal glucose transport independent of enhancement of insulin responses.
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| 33. |
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| 34. |
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| 35. |
- Köhler, Elof, 1980, et al.
(författare)
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Fabrication of High Temperature Thermoelectric Energy Harvesters for Wireless Sensors
- 2013
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Ingår i: Journal of Physics: Conference Series. - : IOP Publishing. - 1742-6588 .- 1742-6596. ; 476:1, s. Art. no. 012036-
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Konferensbidrag (refereegranskat)abstract
- Implementing energy harvesters and wireless sensors in jet engines could simplify development and decrease costs. A thermoelectric energy harvester could be placed in the cooling channels where the temperature is between 500–900°C. This paper covers the synthesis of suitable materials and the design and fabrication of a thermoelectric module. The material choices and other design variables were done from an analytic model by numerical analysis. The module was optimized for 600–800°C with the materials Ba8Ga16Ge30 and La-doped Yb14MnSb11, both having the highest measured zT value in this region. The design goal was to be able to maintain a temperature gradient of at least 200°C with high power output. The La-doped Yb14MnSb11 was synthesized and its structure confirmed by x-ray diffraction. Measurement of properties of this material was not possible due to insufficient size of the crystals. Ba8Ga16Ge30 was synthesized and resulted in an approximated zT value of 0.83 at 700°C. Calculations based on a module with 17 couples gave a power output of 1100mW/g or 600mW/cm2 with a temperature gradient of 200K.
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| 36. |
- Köhler, Elof, 1980, et al.
(författare)
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High temperature energy harvester for wireless sensors
- 2014
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Ingår i: Smart Materials and Structures. - : IOP Publishing. - 0964-1726 .- 1361-665X. ; 23:9, s. Art. no. 095042-
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Tidskriftsartikel (refereegranskat)abstract
- Implementing energy harvesters and wireless sensors in jet engines will simplify development and decrease costs by reducing the need for cables. Such a device could include a small thermoelectric generator placed in the cooling channels of the jet engine where the temperature is between 500-900 degrees C. This paper covers the synthesis of suitable thermoelectric materials, design of module and proof of concept tests of a thermoelectric module. The materials and other design variables were chosen based on an analytic model and numerical analysis. The module was optimized for 600-800 degrees C with the thermoelectric materials n-type Ba8Ga16Ge30 and p-type La-doped Yb14MnSb11, both with among the highest reported figure-of-merit values, zT, for bulk materials in this region. The materials were synthesized and their structures confirmed by x-ray diffraction. Proof of concept modules containing only two thermoelectric legs were built and tested at high temperatures and under high temperature gradients. The modules were designed to survive an ambient temperature gradient of up to 200 degrees C. The first measurements at low temperature showed that the thermoelectric legs could withstand a temperature gradient of 123 degrees C and still be functional. The high temperature measurement with 800 degrees C on the hot side showed that the module remained functional at this temperature.
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| 37. |
- Köhler, Elof, 1980, et al.
(författare)
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Proof of concept thermoelectric energy harvester powering wireless sensor on gas turbine
- 2016
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Ingår i: EVI-GTI and PIWG Joint Conference on Gas Turbine Instrumentation, Berlin, Germany, 27-29 September 2016. - : Institution of Engineering and Technology. ; 2016:CP693
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Konferensbidrag (refereegranskat)abstract
- The thermoelectric energy harvester went from simulations to synthesis of materials and fabrication of test prototypes. We also made measurements on a 1-couple module which did show that the technology is feasible, however very demanding and difficult to build at current state. We also showed with commercial modules that the high temperature energy harvester could power a Wi-Fi at current size of 1 cm2 and 0.4 g if a durable prototype with 7 couples could be manufactured successfully.
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| 38. |
- Li, Qi, 1990, et al.
(författare)
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Compact and low loss electrochemical capacitors using a graphite / carbon nanotube hybrid material for miniaturized systems
- 2019
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Ingår i: Journal of Power Sources. - : Elsevier BV. - 0378-7753. ; 412, s. 374-383
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Tidskriftsartikel (refereegranskat)abstract
- With the establishment of the internet of things (IoT) and the rapid development of advanced microsystems, there is a growing demand to develop electrochemical capacitors (ECs) to replace bulky electrolytic capacitors on circuit boards for AC line filtering, and as a storage unit in energy autonomous systems. For this purpose, ECs must be capable of handling sufficiently high signal frequencies, display minimum energy loss through self-discharge and leakage current as well as maintaining an adequate capacitance. Here, we demonstrate ECs based on mechanically flexible, covalently bonded graphite/vertically aligned carbon nanotubes (graphite/VACNTs) hybrid materials. The ECs employing a KOH electrolyte exhibit a phase angle of −84.8°, an areal capacitance of 1.38 mF cm−2 and a volumetric capacitance (device level) of 345 mF cm−3 at 120 Hz, which is among the highest values for carbon based high frequency ECs. Additionally, the performance as a storage EC for miniaturized systems is evaluated. We demonstrate capacitive charging/discharging at μA current with a gel electrolyte, and sub-μA leakage current reached within 50 s, and 100 nA level equilibrium leakage within 100 s at 2.0 V floating with an ionic liquid electrolyte.
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| 39. |
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| 40. |
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| 41. |
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| 42. |
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| 43. |
- Rahiminejad, Sofia, 1987, et al.
(författare)
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Contactless pin-flange adapter for high-frequency measurements
- 2012
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Ingår i: 23rd Micromechanics and Microsystems Europe Workshop, MME 2012, September 9 - 12, 2012, Ilmenau, Germany.
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Konferensbidrag (refereegranskat)abstract
- We present a first contactless pin-flange adapter for high-frequency measurements based on gap waveguide technology. Conventionally, standard (WR) flanges are used, these require good electrical contact and are sensitive to small gaps. The pin-flange adapter has been fabricated and demonstrated for the frequency range 220-325 GHz. It shows similar or better results than a standard flange or a choke flange without requiring electrical contact. The pin-flange adapter has a lower noise level compared to the other flanges, almost 10 dB lower.
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| 44. |
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| 45. |
- Rahiminejad, Sofia, 1987, et al.
(författare)
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Polymer Gap Adapter for Contactless, Robust, and Fast Measurements at 220-325 GHz
- 2016
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Ingår i: Journal of Microelectromechanical Systems. - : Institute of Electrical and Electronics Engineers (IEEE). - 1057-7157 .- 1941-0158. ; 25:1, s. 160-169
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Tidskriftsartikel (refereegranskat)abstract
- Radiation leakages are a considerable problem when measuring waveguide structures at high frequencies. In order to maintain good electrical contact, flanges need to be tightly and evenly screwed to the device under test. This can be a time-consuming operation, especially with repeated measurements. We present a metamaterial-based adapter, which prohibits leakage even in the presence of gaps at the interconnects. This so-called gap adapter has been fabricated from a metallized polymer (SU8). The reflection coefficient is below -20 dB throughout the band for a 50-mu m gap on both sides of the gap adapter. In comparison, a conventional waveguide with a 50-mu m gap on both sides has a reflection coefficient of -10 dB. The gap adapter can be used to perform fast measurements, since the normal flange screws are redundant. We compare the SU8 gap adapter with a Si version and to a smooth metal waveguide reference disc. The SU8 gap adapter performed better than the Si version and much better than the waveguide disc in all test cases. SU8 gap adapters were used to measure on a waveguide component. The SU8 gap adapters with 50-mu m gaps performed comparable with the waveguide component with the flange screws carefully tightened. The polymer also makes the gap adapter mechanically robust and easy to mass fabricate. [2015-0113]
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| 46. |
- Rahiminejad, Sofia, 1987, et al.
(författare)
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SU8 ridge-gap waveguide resonator
- 2014
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Ingår i: International Journal of Microwave and Wireless Technologies. - : Cambridge University Press (CUP). - 1759-0787 .- 1759-0795. ; 6:5, s. 459-465
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Tidskriftsartikel (refereegranskat)abstract
- In this paper, we present the first ridge-gap waveguide resonator made with a polymer base. It is designed for the frequency range 220-325 GHz, and is fabricated solely using a Au coated two-layer SU8-based process. The design is based on previous work done with Si. The new process has advantages such as fewer and cheaper process steps. The SU8 ridge-gap waveguide resonator is made in order to obtain attenuation characteristics via the measured Q-factor of the resonator. The ridge-gap waveguide resonator has the same dimensions as the previous one fabricated in Si, and the same thickness of the Au coating. The SU8-based resonator shows an attenuation loss of 0.41 dB/mm at 282.2 GHz compared to the Si-based resonator with an attenuation loss of 0.043 dB/mm at 283.5 GHz. This makes the SU8 process a more cost-effective alternative to the Si process
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| 47. |
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| 48. |
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| 49. |
- Rusu, Cristina, et al.
(författare)
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Challenges for Miniaturised Energy Harvesting Sensor Systems
- 2018
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Ingår i: 2018 10th International Conference on Advanced Infocomm Technology (ICAIT). - : Institute of Electrical and Electronics Engineers Inc.. - 9781538679364 ; , s. 214-217
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Konferensbidrag (refereegranskat)
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| 50. |
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