Influence of the preparing conditions on the physicochemical characteristics of glasses for thick film hybrid microelectronics

1994 ◽  
Vol 9 (9) ◽  
pp. 2304-2313 ◽  
Author(s):  
M. Prudenziati ◽  
B. Morten ◽  
P. Savigni ◽  
G. Guizzetti
Keyword(s):  
Thick Film ◽  
Specular Reflection ◽  
Physicochemical Characteristics ◽  
Systematic Investigation ◽  
Glassy Matrix ◽  
Lead Glass ◽  
Preparation Methods ◽  
Composition And Structure ◽  
The Difference ◽  
High Lead

Seven batches of a high-lead glass were used for the preparation of RuO2-based thick film resistors. Investigation of their electrical properties showed a lack of reproducibility of results whose origin was related to changes of the physicochemical properties of the glassy matrix. A systematic investigation of the glass batches, both in form of frit powders and screen printed and fired layers, was carried out with several spectroscopies to detect changes in composition and structure. The spectroscopic methods included x-ray Energy Dispersive Fluorescence (EDS), Scanning Electron Microscopy (SEM), Atomic Absorption (AA), diffuse optical reflection of the powders and specular reflection of the layers, optical transmission, and other complementary methods. The dissolution of Al, due to interaction between the glasses and the alumina substrate, as well as the diffusivity and solubility of Ag due to interaction with the Ag-bearing terminations were measured. The results demonstrated that, apart from small compositional differences, the various batches were characterized by differences in residual stresses, redox reactions, and “microstructure.” The latter was responsible for very notable differences in the optical properties of the glasses, which in turn are closely related with the difference in atomic solubility and diffusivity. Optical spectroscopies have been found to be a suitable means for testing reproducible preparation methods of glass frits for thick-film hybrid microelectronics.

scholarly journals Influencing Factors on the Physicochemical Characteristics of Tea Polysaccharides

Molecules ◽  
2021 ◽  
Vol 26 (11) ◽  
pp. 3457
Author(s):  
Ting Hu ◽  
Peng Wu ◽  
Jianfeng Zhan ◽  
Weixin Wang ◽  
Junfeng Shen ◽  
...  
Keyword(s):  
Influencing Factors ◽  
Biological Activities ◽  
Structural Difference ◽  
Physicochemical Characteristics ◽  
Bioactive Constituents ◽  
Preparation Methods ◽  
Processing Technologies ◽  
Chemical Structures ◽  
Tea Polysaccharides ◽  
Fine Structures

Tea polysaccharides (TPSs) are one of the main bioactive constituents of tea with various biological activities such as hypoglycemic effect, antioxidant, antitumor, and immunomodulatory. The bioactivities of TPSs are directly associated with their structures such as chemical composition, molecular weight, glycosidic linkages, and conformation among others. To study the relationship between the structures of TPSs and their bioactivities, it is essential to elucidate the structure of TPSs, particularly the fine structures. Due to the vast variation nature of monosaccharide units and their connections, the structure of TPSs is extremely complex, which is also affected by several major factors including tea species, processing technologies of tea and isolation methods of TPSs. As a result of the complexity, there are few studies on their fine structures and chain conformation. In the present review, we aim to provide a detailed summary of the multiple factors influencing the characteristics of TPS chemical structures such as variations of tea species, degree of fermentation, and preparation methods among others as well as their applications. The main aspects of understanding the structural difference of TPSs and influencing factors are to assist the study of the structure and bioactivity relationship and ultimately, to control the production of the targeted TPSs with the most desired biological activity.

The identification of high‐lead glass using simple methods

1998 ◽  
Vol 22 (1) ◽  
pp. 12-16
Author(s):  
Gerhard Eggert
Keyword(s):  
Lead Glass ◽  
High Lead

Effect of Film Thickness on Fatigue Strength of TiAl Alloy Coated with TiAlN Film at Elevated Temperature

2005 ◽  
Vol 297-300 ◽  
pp. 1446-1451 ◽  
Author(s):  
Takeshi Kasuya ◽  
Hideto Suzuki
Keyword(s):  
Thin Film ◽  
Fatigue Strength ◽  
Film Thickness ◽  
Thick Film ◽  
Physical Vapor Deposition ◽  
Tial Alloy ◽  
Testing Machine ◽  
Intermetallic Alloy ◽  
Fracture Control ◽  
The Difference

The fatigue strength of TiAl intermetallic alloy coated with TiAlN film was studied in vacuum at 1073K using a SEM-servo testing machine. In addition, three kinds of TiAlN films were given by physical vapor deposition (1, 3, and 10μ m). The fatigue strength of 3μ m was highest. Also, the fatigue strength of 1μ m was lowest. From this result, existence of optimum film thickness was suggested because the difference of fatigue strength arose in each film thickness. The justification for existence of optimum film thickness is competition of 45-degree crack and 90-degree crack. The 45-degree crack is phenomenon seen in the thin film (1μ m), and is caused by plastic deformation of TiAl substrate. The 45-degree crack is the factor of the fatigue strength fall by the side of thin film. In contrast, the 90-degree crack is phenomenon in the thick film (10μ m), and is caused as result of reaction against load to film. The 90-degree crack is the factor of the fatigue strength fall by the side of thick film. In conclusion, the optimum film thickness can perform meso fracture control, and improves fatigue strength.

scholarly journals Evaluation of various sample pre-treatment methods for total and inorganic mercury determination in biological certified reference materials by CVAAS technique

2010 ◽  
Vol 8 (3) ◽  
pp. 594-601 ◽  
Author(s):  
Henryk Matusiewicz ◽  
Ewa Stanisz
Keyword(s):  
Sample Preparation ◽  
Reference Materials ◽  
Total Mercury ◽  
Certified Reference Materials ◽  
Inorganic Mercury ◽  
Preparation Methods ◽  
Decomposition Procedure ◽  
Relative Standard ◽  
The Difference ◽  
Sample Preparation Methods

AbstractSample preparation methods for non-separation cold vapor atomic absorption spectrometry (CVAAS) sequential inorganic mercury speciation in biological certified reference materials (CRMs) were investigated. The methylmercury concentration was calculated as the difference between total and inorganic mercury. Microwave-assisted decomposition method, and three ultrasonic extraction procedures based on acid leaching with HCl and HCOOH and solubilization with TMAH were employed as sample preparation methods. The replacement of a sample decomposition procedure by extraction prior to analysis by CVAAS, as well as the aspect of speciation analysis is discussed. The limits of detection in the sample were determined as 50 and 10 ng L−1 for inorganic and total mercury, which corresponds to absolute detection limits of 40 and 8 ng g−1 for inorganic and total mercury, respectively. The results were in good agreement with the 95% confidence level t-test of the certified values for total and inorganic mercury in the reference materials investigated. From the analysis of the CRMs, it was evident that the difference between the total and inorganic mercury concentrations agrees with the methylmercury concentration. The relative standard deviation was better than 11% for most of the samples.

Variable transfer rates in superfluid helium films

1966 ◽  
Vol 290 (1420) ◽  
pp. 1-13 ◽  
Keyword(s):  
Thick Film ◽  
Superfluid Helium ◽  
Transfer Rate ◽  
Bath Surface ◽  
Helium Films ◽  
Third Sound ◽  
Transfer Rates ◽  
Superfluid Flow ◽  
Helium Bath ◽  
The Difference

From an experimental investigation of superfluid film transfer in narrow beakers in helium II it emerges that there are probably two kinds of film. A ‘normal’ film is formed by superfluid creep over a dry substrate. A ‘thick’ film remains when liquid has drained from a substrate that has previously been immersed in the liquid helium bath. A comparison has been made of the superfluid flow between the two types of film. Scatter of values of transfer rate associated with a normal film is attributed to third sound generated by bath waves impinging on the meniscus at the base of the film. The thick film shows an enhanced rate of transfer which can persist for long periods of time in quiet conditions, but which can be abruptly diminished by disturbances such as bath surface agitation. There is a maximum stable length for a thick film exhibiting the full enhanced rate. The enhanced rate can be as much as 60% greater than the normal rate at 1° K, but the difference between the two rates of transfer disappears above 1.8 °K. No enhanced rate of transfer at any temperature is observed in beakers as large as 8 mm diameter.

THE COMPOSITION AND STRUCTURE OF Y-Ba-Cu-O SUPERCONDUCTORS

1987 ◽  
Vol 01 (02) ◽  
pp. 341-349
Author(s):  
Z.Y. Hua ◽  
C.L. Jia ◽  
H.S. Cheng ◽  
Y.M. Cai ◽  
A.R. Jiang
Keyword(s):  
Single Phase ◽  
Nominal Composition ◽  
High Tc Superconductors ◽  
Small Particles ◽  
High Tc ◽  
Third Phase ◽  
Composition And Structure ◽  
The Difference ◽  
Phase Phase ◽  
Superconductive Phase

High Tc superconductors of Y-Ba-Cu-O system with (Y+Ba):Cu=1~2 have been investigated. Results show that any sample in this system with a proportion of Y:Cu between 0.6 and 1.2 is oxygen-deficient and will be superconductive after sintering in an oxygen flow. In this system all superconductors with different nominal composition have a superconductive phase of perovskite-1ike YBa2Cu3O7 (Phase A), and the difference of constituents is shown in another phase (Phase B) which acts as a gettering center. When the composition has an excess of Y, there will be a third phase (Phase C) which has been identified as small particles of Y2O3 . For an exact nominal proportion of Y:Ba:Cu=1:2:3 , single-phase superconductors can be prepared.

Research note: Leaf cooling curves: measuring leaf temperature in sunlight

2006 ◽  
Vol 33 (5) ◽  
pp. 515 ◽  
Author(s):  
Andrea Leigh ◽  
John D. Close ◽  
Marilyn C. Ball ◽  
Katharina Siebke ◽  
Adrienne B. Nicotra
Keyword(s):  
Surface Temperature ◽  
Close Agreement ◽  
Leaf Surface ◽  
Specular Reflection ◽  
Leaf Temperature ◽  
Cooling Curve ◽  
Cooling Curves ◽  
Infrared Studies ◽  
Leaf Level ◽  
The Difference

Despite the obvious benefits of using thermography under field conditions, most infrared studies at the leaf level are generally conducted in the laboratory. One reason for this bias is that accuracy can potentially be compromised in sunlight because reflected radiation from the leaf might affect the calculation of the temperature measurement. We have developed a method for measuring leaf temperature in sunlight by using thermal imagery to generate cooling curves from which the time constant for cooling, τ, can be calculated. The original temperature of the sunlit leaf may be determined by extrapolating backwards in time. In the absence of specular reflection, there is close agreement between the extrapolated sunlit temperature and the sunlit temperature recorded by the camera. However, when reflected radiation is high, the difference between the initial (incorrect) temperature determined from the sunlit image and the temperature extrapolated from the cooling curve can be > 2°C. Notably, our results demonstrate a close agreement between the extrapolated sunlit temperature and the temperature of the leaf approximately 1 s after being shaded, suggesting that this shaded image provides a good estimate of the original sunlit temperature. Thus, our technique provides two means for measuring leaf surface temperature in sunlight.

Analysis of the Modification Method for Cook-Torrance Model

2014 ◽  
Vol 556-562 ◽  
pp. 4240-4243
Author(s):  
Ming Zhe Li ◽  
Ji Guang Zhao ◽  
Yun Ting Zhou
Keyword(s):  
Specular Reflection ◽  
Scaling Factor ◽  
Remarkable Difference ◽  
Bidirectional Reflectance Distribution Function ◽  
Experiment Data ◽  
Bidirectional Reflectance ◽  
Simulation Data ◽  
Modification Method ◽  
The Difference ◽  
Bidirectional Reflectance Distribution

A visible difference exists between the measured Bidirectional Reflectance Distribution Function (BRDF) and the modeled BRDF. The Cook-Torrance model is chosen to simulate the BRDF for its popularity and flexibility. Taking aluminum for example, this paper analyzes the difference between the experiment data and the simulation data. There is a great and remarkable difference in the situation of specular reflection by comparison in this paper. Consequently, trigonometric factor, numerator and denominator addition factors and scaling factor are brought in the Cook-Torrance model. Finally, a modified Cook-Torrance model is presented. The simulation data of the modified Cook-Torrance model show that it’s more suitable for the analysis of the aluminum BRDF than the classic Cook-Torrance model.

scholarly journals Live-Attenuated Influenza Vaccine Effectiveness in Children From 2009 to 2015–2016: A Systematic Review and Meta-Analysis

2017 ◽  
Vol 4 (3) ◽  
Author(s):  
Herve Caspard ◽  
Raburn M. Mallory ◽  
Jing Yu ◽  
Christopher S. Ambrose
Keyword(s):  
Systematic Review ◽  
Influenza Vaccine ◽  
Meta Analysis ◽  
Systematic Investigation ◽  
H1n1 Vaccine ◽  
Medline Search ◽  
Root Cause ◽  
Live Attenuated Influenza Vaccine ◽  
Children And Young Adults ◽  
The Difference

Abstract Background This systematic review and meta-analysis describes and consolidates findings from all studies that assessed the effectiveness of live-attenuated influenza vaccine (LAIV) against laboratory-confirmed influenza since the 2009 pandemic in children and young adults. Methods A MEDLINE search was conducted for articles published from January 1, 2010 to November 30, 2016. All original publications reporting an effectiveness estimate of LAIV against cases of influenza confirmed by reverse-transcription polymerase chain reaction or culture were retained for analysis. Effectiveness estimates were categorized by LAIV formulation (monovalent, trivalent, and quadrivalent) and strain (any influenza strain, A(H1N1)pdm09, A(H3N2), and B strains). Consolidated estimates were obtained with a random-effects model. Results A total of 24 publications presenting 29 observational studies were retained for meta-analysis. Live-attenuated influenza vaccine was not shown to be effective against A(H1N1)pdm09 strains as a monovalent formulation in 2009–2010 or as a trivalent formulation from 2010–2011 to 2013–2014, but consolidated sample sizes were small. It was effective as a quadrivalent formulation but less effective than inactivated influenza vaccine (IIV). Live-attenuated influenza vaccine was consistently effective against B strains and matched A(H3N2) strains but was not shown to provide significant protection against mismatched A(H3N2) strains in 2014–2015. Conclusions These findings confirm that effectiveness of LAIV against A(H1N1)pdm09 strains has been lower than IIV. A systematic investigation has been initiated to determine the root cause of the difference in effectiveness between pre- and postpandemic A(H1N1) vaccine strains and to identify a more consistently effective A(H1N1)pdm09 vaccine strain.

scholarly journals A Retrospective Analysis of Serous Effusions Based on the Newly Proposed International System for Reporting Serous Fluid Cytopathology: A Report of 3633 Cases in an Oncological Center

2022 ◽  
Author(s):  
Yan-li Zhu ◽  
Wen-hao Ren ◽  
Qian Wang ◽  
Hai-zhu Jin ◽  
Yi-yi Guo ◽  
...  
Keyword(s):  
Diagnostic Accuracy ◽  
Predictive Value ◽  
International System ◽  
High Specificity ◽  
Serous Effusion ◽  
Serous Fluid ◽  
Preparation Methods ◽  
Cytologic Examination ◽  
Risk Of Malignancy ◽  
The Difference

Abstract Background: The International System for Reporting Serous Fluid Cytopathology (TIS) was recently proposed. We retrospectively applied TIS recommendations for reporting the cytological diagnosis of serous effusions and reported our experience.Methods: All the serous effusions from January 2018 to September 2021 were retrieved from the database. Recategorization was performed using the TIS classification, the risk of malignancy (ROM) was calculated for each TIS category, and the performance evaluation was carried out among different samples (pleural, peritoneal and pericardial effusions) and preparation methods (conventional smears, liquid-based preparations and cell-blocks). Results: A total of 3633 cases were studied, 17 (0.5%) were diagnosed as ND, 1100 (30.3%) as NFM, 101 (2.8%) as AUS, 677 (18.6%) as SFM, and 1738 (47.8%) as MAL. The ROM for the categories were found to be 38.5%, 28.6%, 52.1%, 99.4% and 100%, respectively. The ROM for SFM was significantly higher than that for AUS (P < 0.001), while the difference between the ROMs for the IVa and IVb was insignificant. The sensitivity, negative predictive value(NPV) and diagnostic accuracy of liquid-based preparations were all superior to conventional smears and cell-blocks in detecting abnormalities. Using three preparation methods simultaneously had the highest sensitivity, NPV and diagnostic accuracy.Conclusion: Serous effusion cytology has a high specificity and positive predictive value(PPV), and the TIS is a user-friendly reporting system. Liquid-based preparations could improve the sensitivity of diagnosis, and it is best to use three different preparation methods simultaneously for serous effusion cytologic examination.

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