An Investigation of the Process Stability of RF SiP Made of DuPont 943 and 9K7

2011 ◽  
Vol 8 (1) ◽  
pp. 34-41 ◽  
Author(s):  
Thomas Bartnitzek ◽  
Tatyana Purtova ◽  
Christian Rusch ◽  
Slawomir Kaminski ◽  
Till Feger
Keyword(s):  
Dimensional Accuracy ◽  
Thermomechanical Properties ◽  
Low Loss ◽  
Ceramic Substrates ◽  
High Frequencies ◽  
Long Term Stability ◽  
Rf Performance ◽  
Rf Packaging ◽  
The Impact

RF packaging is one of the most challenging but also the fastest growing topic in low temperature cofired ceramic (LTCC) technology. Today LTCC is particularly useful for advanced packages and systems-in-package because of its electrical, functional, and thermomechanical properties as well as its excellent long-term stability and reliability. LTCC combines the potential for miniaturization and low loss handling of high frequencies up to 110 GHz and it also offers the opportunity to integrate additional features. Therefore it has to go through various manufacturing steps and several refirings without any performance degradation or loss of dimensional accuracy. This article discusses the impact of thermal postprocessing on RF characteristics and geometric properties of LTCC. Ceramic substrates with radar front ends, calibration structures, and other test vehicles made of DuPont Green Tape® 943 and 9K7 were cofired following the recommended conditions and refired several times in order to investigate and compare the influence of the postfiring. The flatness, dimensions, and RF performance of the ceramics up to 110 GHz were evaluated and compared.

An Investigation of the Process Stability of RF SiP Made of DuPont 943 and 9K7

2011 ◽  
Vol 2011 (CICMT) ◽  
pp. 000064-000071
Author(s):  
Thomas Bartnitzek ◽  
Tatyana Purtova ◽  
Christian Rusch ◽  
Slawomir Kaminski ◽  
Till Feger
Keyword(s):  
Dimensional Accuracy ◽  
Thermomechanical Properties ◽  
Low Loss ◽  
Ceramic Substrates ◽  
Geometrical Properties ◽  
Long Term Stability ◽  
Rf Performance ◽  
Rf Packaging ◽  
The Impact

RF packaging is one of the most challenging topics in LTCC technology. Today LTCC is particularly capable for advanced packages and systems-in-package because of its electrical, functional, thermomechanical properties as well as its excellent long-term stability and reliability. LTCC combines the potential for miniaturization, low loss handling of high frequencies up to 110 GHz and offers the opportunity to integrate additional features. Therefore it has to go through various manufacturing steps and several refirings without any performance degradation or loss of dimensional accuracy. This paper discusses the impact of thermal post processing on RF characteristics and geometrical properties of LTCC. Ceramic substrates with radar front ends, calibration structures and other test vehicles made of Du Pont Green Tape® 943 and 9k7 were cofired following the recommended conditions and refired several times in order to investigate and compare the influence of the postfiring. The flatness, dimensions and RF performance of the ceramics up to 110 GHz were evaluated and compared.

Separating the impact of oxygen and water on the long-term stability of n-channel perylene diimide thin-film transistors

2015 ◽  
Vol 26 ◽  
pp. 340-344 ◽  
Author(s):  
Ute Zschieschang ◽  
Konstantin Amsharov ◽  
Martin Jansen ◽  
Klaus Kern ◽  
Hagen Klauk ◽  
...  
Keyword(s):  
Thin Film ◽  
Thin Film Transistors ◽  
Perylene Diimide ◽  
Term Stability ◽  
Long Term Stability ◽  
The Impact

Geochemical Behaviour of Uranium in Sedimentary Formations: Insights From a Natural Analogue Study

2009 ◽  
Author(s):  
Ulrich Noseck ◽  
Vaclava Havlova ◽  
Juhani Suksi ◽  
Thomas Brasser ◽  
Radek Cervinka
Keyword(s):  
Current Knowledge ◽  
Natural Analogue ◽  
Near Surface ◽  
Co2 Partial Pressure ◽  
Long Term Stability ◽  
Reducing Conditions ◽  
Phosphate Mineral ◽  
Sedimentary System ◽  
The Impact

Groundwater data from the natural analogue site Ruprechtov have been evaluated with special emphasis on the uranium behaviour in the so-called uranium-rich clay/lignite horizon. In this horizon in-situ Eh-values in the range of −160 to −280 mV seem to be determined by the SO42−/HS− couple. Under these conditions U(IV) is expected to be the preferential redox state in solution. However, on-site measurements in groundwater from the clay/lignite horizon show only a fraction of about 20% occurring in the reduced state U(IV). Thermodynamic calculations reveal that the high CO2 partial pressure in the clay/lignite horizon can stabilise hexavalent uranium, which explains the occurrence of U(VI). The calculations also indicate that the low uranium concentrations in the range between 0.2 and 2.1μg/l are controlled by amorphous UO2 and/or the U(IV) phosphate mineral ningyoite. This confirms the findings from previous work that the uranium (IV) mineral phases are long-term stable under the reducing conditions in the clay/lignite horizon without any signatures for uranium mobilisation. It supports the current knowledge of the geological development of the site and is also another important indication for the long-term stability of the sedimentary system itself, namely of the reducing geochemical conditions in the near-surface (30m to 60 m deep) clay/lignite horizon. Further work with respect to the impact of changes in redox conditions on the uranium speciation is on the way.

The impact of chronic untreated hyperglycaemia on the long-term stability of paraoxonase 1 (PON1) and antioxidant status in human sera

2013 ◽  
Vol 67 (1) ◽  
pp. 55-59 ◽  
Author(s):  
Muiruri Macharia ◽  
Andre P Kengne ◽  
Diane M Blackhurst ◽  
Rajiv T Erasmus ◽  
Tandi E Matsha
Keyword(s):  
Antioxidant Status ◽  
Paraoxonase 1 ◽  
Term Stability ◽  
Long Term Stability ◽  
Human Sera ◽  
The Impact

Thermal treatment of plutonium contaminated material (PCM) waste

MRS Advances ◽  
2017 ◽  
Vol 2 (13) ◽  
pp. 735-740
Author(s):  
Luke Boast ◽  
M.C. Stennett ◽  
Neil C. Hyatt
Keyword(s):  
Thermal Treatment ◽  
Long Term Stability ◽  
Treatment Processes ◽  
Matrix Interactions ◽  
Fundamental Understanding ◽  
Treatment Technologies ◽  
Key Drivers ◽  
The Impact

ABSTRACTKey drivers for the application of thermal treatment processes include the reduced volume, improved passive safety, and superior long term stability of the vitrified wasteform products. These advantages have led to a renewed interest in thermally treating various UK ILW streams. To support the increased investment in thermal treatment technologies a fundamental understanding of the processes and the impact of waste inventory needs to be established. The research described in this report aims to provide the evidence necessary to support a major investment in thermal treatment of Plutonium Contaminated Materials (PCM). The report describes the use of laboratory scale waste simulants to develop an understanding of the waste and matrix interactions during thermal treatment of PCM waste. The report includes the thermal treatment process and characterization of the vitrified product.

scholarly journals Sensing with Chirality Pure near Infrared Fluorescent Carbon Nanotubes

2020 ◽  
Author(s):  
Robert Nißler ◽  
Larissa Kurth, ◽  
Han Li ◽  
Alexander Spreinat ◽  
Ilyas Kuhlemann ◽  
...  
Keyword(s):  
Carbon Nanotubes ◽  
Dna Sequences ◽  
Near Infrared ◽  
Single Wall Carbon Nanotubes ◽  
Term Stability ◽  
Long Term Stability ◽  
Sensing Applications ◽  
Main Challenge ◽  
The Impact

Semiconducting single wall carbon nanotubes (SWCNTs) fluoresce in the near infrared (NIR) and the emission wavelength depends on their chirality (n,m). Interactions with the environment affect the fluorescence and can be tailored by functionalizing SWCNTs with biopolymers such as DNA, which is the basis for fluorescent biosensors. So far, such biosensors were mainly assembled from mixtures of SWCNT chiralities with large spectral overlap, which affects sensitivity as well as selectivity and prevents multiplexed sensing. The main challenge to gain chirality pure sensors has been to combine approaches to isolate specific SWCNTs and generic (bio)functionalization approaches. Here, we created chirality pure SWCNT-based NIR biosensors for important analytes such as neurotransmitters and investigated the impact of SWCNT chirality/handedness as well as long-term stability and sensitivity. For this purpose, we used aqueous two-phase extraction (ATPE) to gain chirality pure (6,5)-, (7,5)-, (9,4)- and (7,6)- SWCNTs (emission at ~ 990, 1040, 1115 and 1130 nm). Exchange of the surfactant sodium deoxycholate (DOC) to specific singlestranded (ss)DNA sequences yielded monochiral sensors for small analytes (dopamine, riboflavin, ascorbic acid, pH). DOC used in the separation process was completely removed because residues impaired sensing. The assembled monochiral sensors were up to 10 times brighter than their non-purified counterparts and the ssDNA sequence affected absolute fluorescence intensity as well as colloidal (long-term) stability and selectivity for the analytes. (GT)40-(6,5)-SWCNTs displayed the maximum fluorescence response to the neurotransmitter dopamine (+140 %, Kd = 1.9 x10-7 M) and a long-term stability > 14 days. Furthermore, the specific ssDNA sequences imparted selectivity to the analytes independent of SWCNT chirality and handedness of (+/-) (6,5)-SWCNTs. These monochiral/single-color SWCNTs enabled ratiometric/multiplexed sensing of dopamine, riboflavin, H2O2 and pH. In summary, we demonstrated the assembly, characteristics and potential of monochiral (single-color) SWCNTs for multiple NIR fluorescent sensing applications.

scholarly journals Sensing with Chirality Pure near Infrared Fluorescent Carbon Nanotubes

2020 ◽  
Author(s):  
Robert Nißler ◽  
Larissa Kurth, ◽  
Han Li ◽  
Alexander Spreinat ◽  
Ilyas Kuhlemann ◽  
...  
Keyword(s):  
Carbon Nanotubes ◽  
Dna Sequences ◽  
Near Infrared ◽  
Single Wall Carbon Nanotubes ◽  
Term Stability ◽  
Long Term Stability ◽  
Sensing Applications ◽  
Main Challenge ◽  
The Impact

Semiconducting single wall carbon nanotubes (SWCNTs) fluoresce in the near infrared (NIR) and the emission wavelength depends on their chirality (n,m). Interactions with the environment affect the fluorescence and can be tailored by functionalizing SWCNTs with biopolymers such as DNA, which is the basis for fluorescent biosensors. So far, such biosensors were mainly assembled from mixtures of SWCNT chiralities with large spectral overlap, which affects sensitivity as well as selectivity and prevents multiplexed sensing. The main challenge to gain chirality pure sensors has been to combine approaches to isolate specific SWCNTs and generic (bio)functionalization approaches. Here, we created chirality pure SWCNT-based NIR biosensors for important analytes such as neurotransmitters and investigated the impact of SWCNT chirality/handedness as well as long-term stability and sensitivity. For this purpose, we used aqueous two-phase extraction (ATPE) to gain chirality pure (6,5)-, (7,5)-, (9,4)- and (7,6)- SWCNTs (emission at ~ 990, 1040, 1115 and 1130 nm). Exchange of the surfactant sodium deoxycholate (DOC) to specific singlestranded (ss)DNA sequences yielded monochiral sensors for small analytes (dopamine, riboflavin, ascorbic acid, pH). DOC used in the separation process was completely removed because residues impaired sensing. The assembled monochiral sensors were up to 10 times brighter than their non-purified counterparts and the ssDNA sequence affected absolute fluorescence intensity as well as colloidal (long-term) stability and selectivity for the analytes. (GT)40-(6,5)-SWCNTs displayed the maximum fluorescence response to the neurotransmitter dopamine (+140 %, Kd = 1.9 x10-7 M) and a long-term stability > 14 days. Furthermore, the specific ssDNA sequences imparted selectivity to the analytes independent of SWCNT chirality and handedness of (+/-) (6,5)-SWCNTs. These monochiral/single-color SWCNTs enabled ratiometric/multiplexed sensing of dopamine, riboflavin, H2O2 and pH. In summary, we demonstrated the assembly, characteristics and potential of monochiral (single-color) SWCNTs for multiple NIR fluorescent sensing applications.

A new direct-viewing chemotaxis chamber

1991 ◽  
Vol 99 (4) ◽  
pp. 769-775
Author(s):  
D. Zicha ◽  
G.A. Dunn ◽  
A.F. Brown
Keyword(s):  
Dimensional Accuracy ◽  
Term Stability ◽  
Dimensional Precision ◽  
Long Term Stability ◽  
Precise Knowledge ◽  
Higher Dimensional ◽  
Counting Chamber ◽  
New Form ◽  
Linear Concentration

A new form of chamber for studying chemotaxis, similar in principle to the Zigmond chamber, allows the behaviour of the cells in a linear concentration gradient to be observed directly. The chamber was developed mainly for studying chemotaxis in fibroblasts using interferometric microscopy and the main design criteria were that it should have better optical characteristics, a higher dimensional precision and better long-term stability than the Zigmond chamber. It is made entirely from glass by grinding a blind circular well centrally in the counting platform of a Helber bacteria counting chamber. This procedure leaves an annular ‘bridge’, approximately 1 mm wide, between the new inner circular well and the original outer annular well. This bridge fulfils the same function as the linear bridge of the Zigmond chamber but the precise construction of the counting chamber ensures that a gap of 20 microns between bridge and coverslip can be accurately and repeatedly achieved when the chamber is assembled. It is envisaged that the improved optical clarity, dimensional accuracy and long-term stability of the new chamber will be advantageous in other applications, particularly in studies requiring critical microscopy or a precise knowledge of the gradient and in studies of cells, such as fibroblasts, that move much more slowly than neutrophils.

scholarly journals Lip-to-incisor Relationship and Postorthodontic Long-term Stability of Cover-bite Treatment

2006 ◽  
Vol 76 (6) ◽  
pp. 942-949 ◽  
Author(s):  
Bernd G. Lapatki ◽  
Dirk Baustert ◽  
Jürgen Schulte-Mönting ◽  
Sibylle Frucht ◽  
Irmtrud E. Jonas
Keyword(s):  
Central Incisor ◽  
Lower Lip ◽  
Maxillary Central Incisor ◽  
Term Stability ◽  
Long Term Stability ◽  
Lateral Cephalograms ◽  
Inducing Factors ◽  
Line Level ◽  
The Impact

Abstract Objective: To investigate the impact of a persisting high lip line and other potential relapse-inducing factors on long-term stability of orthodontic correction of retroinclined maxillary central incisors. Materials and Methods: Thirty-one cover-bite (“Deckbiss”) patients with retroinclined maxillary central incisors and a deep frontal overbite were evaluated. The maxillary central incisor inclination was determined odontometrically with study models made pretreatment, posttreatment, and at a follow-up examination (mean posttherapeutic interval: 9.0 years). The lip-to-incisor relationship, the interincisal angle, and the anteroposterior maxillary central incisor position were measured on lateral cephalograms taken after active treatment. Results: The relapse tendency of the orthodontic correction of the retroinclined maxillary central incisors displayed great interindividual variability with a range of posttherapeutic inclination change of −6.75° to +8.00°. Multiple regression analysis revealed an increased tendency for relapse in patients with (1) a high posttherapeutic (dorsal) lip line level combined with the maxillary central incisor and lower lip contact only in the incisal crown area (P < .01) and (2) a marked therapeutically induced inclination change of the maxillary central incisors (P < .05). Interrelations between the relapse of the corrected maxillary central incisors and other evaluated parameters were not statistically significant. Conclusions: For maximum treatment stability, the elimination of an excessive overlap of the upper incisors by the lower lip should be regarded as one of the most important therapeutic objectives when treating this malocclusion.

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