Influence of co-firing process condition on low temperature co-fired ceramics membrane deflection

2014 ◽  
Vol 31 (3) ◽  
pp. 193-200
Author(s):  
Dominik Jurków
Keyword(s):  
Low Temperature ◽  
Pressure Sensors ◽  
Process Condition ◽  
Statistical Design ◽  
Firing Process ◽  
Process Conditions ◽  
Optimal Process ◽  
Content Type ◽  
Applied Design ◽  
Membrane Deflection

Purpose – The paper aims to present the influence of the co-firing process conditions of low temperature co-fired ceramics (LTCC) on the deformation of thin LTCC membranes. Design/methodology/approach – The statistical design of the experiment methodology was used in the frame of these investigations to reduce the time and costs of the experiments and to ensure easier interpretation of the obtained results. Moreover, this conception permits the rough estimation of the membrane deflection fired at optimal process conditions. Findings – The applied design of the experiment methodology allowed the researchers to find the optimal co-firing process conditions and to estimate the membrane deflection at the optimal process conditions. The estimation fits well with the results of real measurement that was conducted to confirm the estimation precision. Research limitations/implications – The experiment was conducted for only one type of LTCC, DP951. The precision of the design of the experiment optimization and estimation of the response at optimal conditions depend on the described object. Therefore, the findings of this paper do not have to be generally true for other LTCC tapes, and if other LTCC tapes deformation should be investigated, then similar analysis shall be conducted for them. Practical implications – The deformation of LTCC membranes affects the sensitivity and repeatability of LTCC acceleration and pressure sensors. Hence, the decrease of membrane deflection increases the usability of LTCC in such applications. Originality/value – This paper presents simple optimization of co-firing process conditions of LTCC devices using statistical design of the experiment.

Effect of Temperature and Cooling Rate on the Microstructures of 35MnB and 25Mn Tubes during Heat Treatment

2016 ◽  
Vol 866 ◽  
pp. 196-200
Author(s):  
Sun Ho Jung ◽  
S. Lee ◽  
J. Lee
Keyword(s):  
Heat Treatment ◽  
Cooling Rate ◽  
Process Condition ◽  
Effect Of Temperature ◽  
Process Conditions ◽  
Optimal Process ◽  
Steel Tubes ◽  
Band Structures ◽  
Mechanical Quality

Band structures with pearlite and ferrite aligned as stripes can be created during the heat treatment of carbon steel. Since band structures undermine the mechanical quality of end products, it is highly important to select a process condition that will not create band structures as a result of heat treatment. This study verified the effect of temperature and cooling rate on the creation of band structures during heat treatment of 35MnB and 25Mn steel tubes for drive shafts and also considered the optimal process conditions to remove band structures or prevent their creation. The experimental results suggest that, during heat treatment of 35MnB and 25Mn steel tubes, it is most effective to ensure a cooling rate faster than furnace cooling in order to prevent band structures.

scholarly journals Optimizing TEG Dehydration Process under Metamodel Uncertainty

Energies ◽  
2021 ◽  
Vol 14 (19) ◽  
pp. 6177
Author(s):  
Rajib Mukherjee ◽  
Urmila M. Diwekar
Keyword(s):  
Parameter Optimization ◽  
Process Simulation ◽  
Process Condition ◽  
Operating Conditions ◽  
Computational Time ◽  
Process Conditions ◽  
Dehydration Process ◽  
Optimal Process ◽  
Emission Mitigation ◽  
Metamodel Uncertainty

Natural gas processing requires the removal of acidic gases and dehydration using absorption, mainly conducted in tri-ethylene glycol (TEG). The dehydration process is accompanied by the emission of volatile organic compounds, including BTEX. In our previous work, multi-objective optimization was undertaken to determine the optimal operating conditions in terms of the process parameters that can mitigate BTEX emission using data-driven metamodeling and metaheuristic optimization. Data obtained from a process simulation conducted using the ProMax® process simulator were used to develop a metamodel with machine learning techniques to reduce the computational time of the iterations in a robust process simulation. The metamodels were created using limited samples and some underlying phenomena must therefore be excluded. This introduces the so-called metamodeling uncertainty. Thus, the performance of the resulting optimized process variables may be compromised by the lack of adequately accounting for the uncertainty introduced by the metamodel. In the present work, the bias of the metamodel uncertainty was addressed for parameter optimization. An algorithmic framework was developed for parameter optimization, given these uncertainties. In this framework, metamodel uncertainties are quantified using real model data to generate distribution functions. We then use the novel Better Optimization of Nonlinear Uncertain Systems (BONUS) algorithm to solve the problem. BTEX mitigation is used as the objective of the optimization. Our algorithm allows the determination of the optimal process condition for BTEX emission mitigation from the TEG dehydration process under metamodel uncertainty. The BONUS algorithm determines optimal process conditions compared to those from the metaheuristic method, resulting in BTEX emission mitigation up to 405.25 ton/yr.

A novel approach for the fabrication of low-stress bimorph RF-MEMS switches

2017 ◽  
Vol 13 (1) ◽  
pp. 116-121
Author(s):  
Hitesh Kumar Sharma ◽  
Shalu Rani
Keyword(s):  
Low Temperature ◽  
Insertion Loss ◽  
Rf Mems ◽  
Low Cost ◽  
Chemical Vapor ◽  
Process Conditions ◽  
Temperature Plasma ◽  
Content Type ◽  
Mems Switches ◽  
Novel Approach

Purpose The purpose of this paper is to design a low-cost stress bimorph RF-MEMS switch which is the desired transmission area application. Design/methodology/approach The bimorph structure of the low-temperature plasma-enhanced chemical vapor deposition (PECVD) of thermal oxide and gold are utilized to create the vibrating membrane. The effects of process conditions of low-temperature oxide deposited using the PECVD technique enable stress-free deposition of the key structural layer. Findings Scanning electron microscope images of the RF micro-switch confirms negligible stress in the released structure. The RF performances of this device exhibit isolation around 43 dB of up to 50 GHz in the OFF-state position and an insertion loss of less than 0.18 dB in the ON-state. Originality/value The finite element method results show good isolation of 43 dB and less insertion loss of 0.18 dB.

Optimization of nutritional beverage developed from radish, sugarcane and herbal extract using response surface methodology

2018 ◽  
Vol 48 (5) ◽  
pp. 733-743 ◽  
Author(s):  
Gagandeep Kaur ◽  
Vikas Kumar ◽  
Ankit Goyal ◽  
Beenu Tanwar ◽  
Jaspreet Kaur
Keyword(s):  
Salt Concentration ◽  
Statistical Significance ◽  
Statistical Design ◽  
Titratable Acidity ◽  
Sugarcane Juice ◽  
Soluble Solids ◽  
Herbal Extract ◽  
Process Conditions ◽  
Content Type ◽  
Overall Acceptability

Purpose Radish (Raphanus sativus) is valued for its nutritive and medicinal properties, but its juice is not palatable because of the pungent flavor. The purpose of this study is to optimize the blending process of radish juice by using sugarcane juice, herbal extract and salt concentration. Design/methodology/approach The statistical design provided 20 formulations; where herbal extract concentration varied from 0.5 to 2.5 per cent, sugarcane juice concentration from 20 to 50 per cent and salt concentration from 0 to 1.5 per cent. Findings The p = 0.05 was used to designate the statistical significance of all the responses under study. Different product formulations had total soluble solids (TSS) that ranged from 9.7 to 15.0°Brix, titratable acidity from 0.6 to 1.3%, pH from 3.3 to 4.0, reducing sugars from 0.6 to 0.8%, total sugars from 9.4 to 3.1%, total protein from 172.9 to 304.8 mg/100 ml, total phenols from 25.5 to 29.8 mg/100 ml, ascorbic acid from 10.4 to 19.8 mg/100 ml, antioxidant activity from 77.3 to 83.6% and overall acceptability from 5.6 to 7.7. Sugarcane juice concentration of 30%, herbal extract mixture and salt concentrations of 1 and 1.5%, respectively, were the optimized process conditions for the preparation of nutritional radish juice achieved with the best fit of desirability, i.e. 0.88. Cluster analysis revealed that concentration of sugarcane juice had the maximum significant effect on the quality characteristics of nutritional radish beverage as compared to the other two variables under study. Originality/value The developed product can help to promote the use of radish as a substrate for the beverage industry.

scholarly journals Temperature Profile in Rubber Injection Molding: Application of a Recently Developed Testing Method to Improve the Process Simulation and Calculation of Curing Kinetics

Polymers ◽  
2021 ◽  
Vol 13 (3) ◽  
pp. 380
Author(s):  
Martin Traintinger ◽  
Roman Christopher Kerschbaumer ◽  
Bernhard Lechner ◽  
Walter Friesenbichler ◽  
Thomas Lucyshyn
Keyword(s):  
Injection Molding ◽  
Temperature Profile ◽  
Pressure Sensors ◽  
Simulation Software ◽  
Relative Degree ◽  
Actual State ◽  
Process Conditions ◽  
Inlet Temperature ◽  
Degree Of Cure ◽  
Mass Temperature

Injection molding of rubber compounds is an easily conducted yet sophisticated method for rubber processing. Simulation software is used to examine the optimal process conditions, identify failure scenarios, and save resources. Due to the complexity of the entire process, various aspects have to be considered in the numerical approach. This contribution focused on a comparison of process simulations with various definitions of the material’s inlet temperature, ranging from a stepwise increase, but constant temperature, to an exact axial mass temperature profile prior to injection. The latter was obtained with a specially designed, unique test stand consisting of a plasticizing cylinder equipped with pressure sensors, a throttle valve for pressure adjustments, and a measurement bar with thermocouples for the determination of the actual state of the mass temperature. For the verification of the theoretical calculations, practical experiments were conducted on a rubber injection molding machine equipped with the mold used in the simulation. The moldings, obtained at different vulcanization time, were characterized mechanically and the results were normalized to a relative degree of cure in order to enable comparison of the real process and the simulation. Considering the actual state of the mass temperature, the simulation showed an excellent correlation of the measured and calculated mass temperatures in the cold runner. Additionally, the relative degree of cure was closer to reality when the mass temperature profile after dosing was applied in the simulation.

scholarly journals Indicative Marker Microbiome Structures Deduced from the Taxonomic Inventory of 67 Full-Scale Anaerobic Digesters of 49 Agricultural Biogas Plants

2021 ◽  
Vol 9 (7) ◽  
pp. 1457
Author(s):  
Julia Hassa ◽  
Johanna Klang ◽  
Dirk Benndorf ◽  
Marcel Pohl ◽  
Benedikt Hülsemann ◽  
...  
Keyword(s):  
Stable Process ◽  
Process Condition ◽  
Full Scale ◽  
Process Models ◽  
Process Efficiency ◽  
Process Conditions ◽  
Rrna Gene ◽  
General Process ◽  
Specific Distribution ◽  
Biogas Plants

There are almost 9500 biogas plants in Germany, which are predominantly operated with energy crops and residues from livestock husbandry over the last two decades. In the future, biogas plants must be enabled to use a much broader range of input materials in a flexible and demand-oriented manner. Hence, the microbial communities will be exposed to frequently varying process conditions, while an overall stable process must be ensured. To accompany this transition, there is the need to better understand how biogas microbiomes respond to management measures and how these responses affect the process efficiency. Therefore, 67 microbiomes originating from 49 agricultural, full-scale biogas plants were taxonomically investigated by 16S rRNA gene amplicon sequencing. These microbiomes were separated into three distinct clusters and one group of outliers, which are characterized by a specific distribution of 253 indicative taxa and their relative abundances. These indicative taxa seem to be adapted to specific process conditions which result from a different biogas plant operation. Based on these results, it seems to be possible to deduce/assess the general process condition of a biogas digester based solely on the microbiome structure, in particular on the distribution of specific indicative taxa, and without knowing the corresponding operational and chemical process parameters. Perspectively, this could allow the development of detection systems and advanced process models considering the microbial diversity.

Precursor design and engineering for low-temperature deposition of gate dielectrics for thin film transistors

2011 ◽  
Vol 1287 ◽  
Author(s):  
Anupama Mallikarjunan ◽  
Laura M Matz ◽  
Andrew D Johnson ◽  
Raymond N Vrtis ◽  
Manchao Xiao ◽  
...  
Keyword(s):  
Thin Film ◽  
Low Temperature ◽  
Thin Film Transistors ◽  
Moisture Absorption ◽  
Silicon Oxide ◽  
Chemical Vapor ◽  
Silicon Oxycarbide ◽  
Process Conditions ◽  
Structure Property ◽  
Oh Groups

ABSTRACTThe electrical and physical quality of gate and passivation dielectrics significantly impacts the device performance of thin film transistors (TFTs). The passivation dielectric also needs to act as a barrier to protect the TFT device. As low temperature TFT processing becomes a requirement for novel applications and plastic substrates, there is a need for materials innovation that enables high quality plasma enhanced chemical vapor deposition (PECVD) gate dielectric deposition. In this context, this paper discusses structure-property relationships and strategies for precursor development in silicon nitride, silicon oxycarbide (SiOC) and silicon oxide films. Experiments with passivation SiOC films demonstrate the benefit of a superior precursor (LkB-500) and standard process optimization to enable lower temperature depositions. For gate SiO2 deposition (that are used with polysilicon TFTs for example), organosilicon precursors containing different types and amounts of Si, C, O and H bonding were experimentally compared to the industry standard TEOS (tetraethoxysilane) at different process conditions and temperatures. Major differences were identified in film quality especially wet etch rate or WER (correlating to film density) and dielectric constant (k) values (correlating to moisture absorption). Gate quality SiO2 films can be deposited by choosing precursors that can minimize residual Si-OH groups and enable higher density stable moisture-free films. For e.g., the optimized precursor AP-LTO® 770 is clearly better than TEOS for low temperature PECVD depositions based on density, WER, k charge density (measured by flatband voltage or Vfb); and leakage and breakdown voltage (Vbd) measurements. The design and development of such novel precursors is a key factor to successfully enable manufacturing of advanced low temperature processed devices.

scholarly journals Association of the Cold Shock DEAD-Box RNA Helicase RhlE to the RNA Degradosome in Caulobacter crescentus

2017 ◽  
Vol 199 (13) ◽  
Author(s):  
Angel A. Aguirre ◽  
Alexandre M. Vicente ◽  
Steven W. Hardwick ◽  
Daniela M. Alvelos ◽  
Ricardo R. Mazzon ◽  
...  
Keyword(s):  
Low Temperature ◽  
Caulobacter Crescentus ◽  
Immunoblot Analysis ◽  
Rna Helicase ◽  
Rnase E ◽  
Rna Helicases ◽  
Content Type ◽  
Dead Box ◽  
Rna Degradosome ◽  
The Dead

ABSTRACT In diverse bacterial lineages, multienzyme assemblies have evolved that are central elements of RNA metabolism and RNA-mediated regulation. The aquatic Gram-negative bacterium Caulobacter crescentus, which has been a model system for studying the bacterial cell cycle, has an RNA degradosome assembly that is formed by the endoribonuclease RNase E and includes the DEAD-box RNA helicase RhlB. Immunoprecipitations of extracts from cells expressing an epitope-tagged RNase E reveal that RhlE, another member of the DEAD-box helicase family, associates with the degradosome at temperatures below those optimum for growth. Phenotype analyses of rhlE, rhlB, and rhlE rhlB mutant strains show that RhlE is important for cell fitness at low temperature and its role may not be substituted by RhlB. Transcriptional and translational fusions of rhlE to the lacZ reporter gene and immunoblot analysis of an epitope-tagged RhlE indicate that its expression is induced upon temperature decrease, mainly through posttranscriptional regulation. RNase E pulldown assays show that other proteins, including the transcription termination factor Rho, a second DEAD-box RNA helicase, and ribosomal protein S1, also associate with the degradosome at low temperature. The results suggest that the RNA degradosome assembly can be remodeled with environmental change to alter its repertoire of helicases and other accessory proteins. IMPORTANCE DEAD-box RNA helicases are often present in the RNA degradosome complex, helping unwind secondary structures to facilitate degradation. Caulobacter crescentus is an interesting organism to investigate degradosome remodeling with change in temperature, because it thrives in freshwater bodies and withstands low temperature. In this study, we show that at low temperature, the cold-induced DEAD-box RNA helicase RhlE is recruited to the RNA degradosome, along with other helicases and the Rho protein. RhlE is essential for bacterial fitness at low temperature, and its function may not be complemented by RhlB, although RhlE is able to complement for rhlB loss. These results suggest that RhlE has a specific role in the degradosome at low temperature, potentially improving adaptation to this condition.

Study on Extracting Potassium from Potassium Feldspar with Molten Salt Leaching Method

2012 ◽  
Vol 524-527 ◽  
pp. 1078-1081
Author(s):  
Jian Guo Song ◽  
Xin Zhi Wang ◽  
Shao Dan Xiao ◽  
Wei Liu
Keyword(s):  
Reaction Time ◽  
Molten Salt ◽  
Potassium Feldspar ◽  
Process Conditions ◽  
Temperature Reaction ◽  
Optimal Process ◽  
Potash Feldspar ◽  
Salt Leaching ◽  
Effects Of Temperature

This article aims to study the technology of extracting potassium from potassium feldspar with molten salt leaching method and to analyze the effects of temperature, reaction time and other factors on extracting potassium, concluding the optimal process conditions of extracting potassium with molten leaching method from potash feldspar.

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