scholarly journals The retraction of jetted slender viscoelastic liquid filaments

2021 ◽  
Vol 929 ◽  
Author(s):  
Uddalok Sen ◽  
Charu Datt ◽  
Tim Segers ◽  
Herman Wijshoff ◽  
Jacco H. Snoeijer ◽  
...  
Keyword(s):  
Inkjet Printing ◽  
Polymer Concentration ◽  
Droplet Formation ◽  
Deborah Number ◽  
Upper And Lower Bounds ◽  
Satellite Droplet ◽  
Primary Droplet ◽  
The Stability

Long and slender liquid filaments are produced during inkjet printing, which can subsequently either retract to form a single droplet, or break up to form a primary droplet and one or more satellite droplets. These satellite droplets are undesirable since they degrade the quality and reproducibility of the print, and lead to contamination within the enclosure of the print device. Existing strategies for the suppression of satellite droplet formation include, among others, adding viscoelasticity to the ink. In the present work, we aim to improve the understanding of the role of viscoelasticity in suppressing satellite droplets in inkjet printing. We demonstrate that very dilute viscoelastic aqueous solutions ( $\text {concentrations} \sim 0.003\,\%$  wt. polyethylene oxide, corresponding to nozzle Deborah number $De_{n}\sim 3$ ) can suppress satellite droplet formation. Furthermore, we show that, for a given driving condition, upper and lower bounds of polymer concentration exist, within which satellite droplets are suppressed. Satellite droplets are formed at concentrations below the lower bound, while jetting ceases for concentrations above the upper bound (for fixed driving conditions). Moreover, we observe that, with concentrations in between the two bounds, the filaments retract at velocities larger than the corresponding Taylor–Culick velocity for the Newtonian case. We show that this enhanced retraction velocity can be attributed to the elastic tension due to polymer stretching, which builds up during the initial jetting phase. These results shed some light on the complex interplay between inertia, capillarity and viscoelasticity for retracting liquid filaments, which is important for the stability and quality of inkjet printing of polymer solutions.

Structural and functional analysis of reconnaissance and fire system and decomposition of its functions and subsystems

2021 ◽  
pp. 38-48
Author(s):  
O. Maistrenko ◽  
O. Karavanov ◽  
A. Shcherba
Keyword(s):  
Functional Analysis ◽  
Fire Damage ◽  
Expert Group ◽  
Expert Evaluation ◽  
Military Conflicts ◽  
Main Factors ◽  
The Stability ◽  
The Impact

It is established that the role of reconnaissance and fire systems in the implementation of enemy fire damage in military conflicts occurring at the beginning of the XXI century. Increased  to 75%. However, it was found that the effectiveness of these systems depends on the quality of their equipment. The main factors that are often not taken into account in the acquisition are the possibility, interoperability, stability of each element, the impact of elements on the stability of each other and the functioning of the RVS as a whole. The analysis of recent research and publications has shown that as of today, the approaches to determining the composition of reconnaissance fire systems taking into account these factors are not justified. Given the above, it was decided to conduct a structural and functional analysis of the reconnaissance fire system and the decomposition of its functions and subsystems. To this end, based on the method of cluster analysis, an algorithm for combining a set of tasks performed by reconnaissance and fire systems into groups has been developed and substantiated. The method of expert evaluation was used to obtain substantiated data on the implementation of such a merger. According to the proposed algorithm, the main tasks were first identified, which involve reconnaissance and fire systems. Subsequently, an expert group was formed and the coefficient of relative competence of each member of the expert group was determined. The experts were then asked to combine the identified tasks according to their characteristics into an arbitrary number of groups. After processing the opinions of experts, 10 characteristic groups were identified. Finally, the experts were asked to combine the obtained groups in such a way that each association consisted of similar objects and the objects of different associations differed significantly. The results of the work revealed the functional interconnectedness of the tasks, processes and subsystems of the reconnaissance and fire system. It is also established that a typical reconnaissance fire system will consist of three subsystems (control, reconnaissance and fire influence), which perform specific functions for each of them.

scholarly journals The Role of Cultivation Systems in Quality Sugar Beet Production

2005 ◽  
pp. 134-138
Author(s):  
Kinga Diána Ungai ◽  
Zoltán Győri
Keyword(s):  
Sugar Beet ◽  
Production System ◽  
Plant Protection ◽  
Plant Production ◽  
High Yield ◽  
Yield And Quality ◽  
The Stability ◽  
Saccharose Content

Producing sugar beet, as it is a demanding field crop, has contributed to the raising standard of plant production. It has an outstanding place among the plants that are cultivated in the intensive plant production system. Rentability of sugar manufacture is determined by the stability of yield and the quality (saccharose content) of sugar beet. In this way, the fundamental interest both of the producers and the processing industry is high yield and quality, year by year. The yield and the quality of the sugar beet are mainly determined by the plant production system, so we studied the effect of fertilization, irrigation and plant protection.

scholarly journals Investigation of the influence of modification of the working tool for the manufacture of niobium case products

2021 ◽  
Vol 2094 (4) ◽  
pp. 042006
Author(s):  
E Yu Remshev ◽  
Z N Rasulov ◽  
S A Voinash ◽  
V A Sokolova ◽  
I A Teterina ◽  
...  
Keyword(s):  
Significant Proportion ◽  
Machine Building ◽  
Test Cycle ◽  
New Methods ◽  
Urgent Task ◽  
Main Production ◽  
The Stability ◽  
Cold Stamping

Abstract The main production of machine-building enterprises of various industries is the production of metal parts and products, 90-95% of which are manufactured using metal processing by pressure. Ensuring the stability of the technological processes of cold stamping is impossible without the use of interoperative coatings, which play the role of lubrication, preventing the diffusion “setting” (interpenetration at the atomic-molecular level) of the processed materials and tools. Therefore, one of the tasks in constructing the technology for manufacturing parts from these materials is to conduct a test cycle to establish the most acceptable coatings at the intermediate stages of processing. In the process of studying the operability and manufacturability, it is also advisable to use new methods for evaluating quality indicators at separate stages of processing semi-finished products and at the stages of control of finished products, which allows practically eliminating defects due to internal defects, ensuring the uniformity of the microstructure and predicting the operability of finished products during operation. Ensuring the quality of stamped semi-finished products made of refractory metals (niobium, molybdenum) is an urgent task due to the significant proportion of defects during cold stamping of these parts.

Party Systems: Types, Dimensions, and Explanations

2020 ◽  
Author(s):  
Zsolt Enyedi ◽  
Fernando Casal Bértoa
Keyword(s):  
Party System ◽  
Balance Of Power ◽  
Party Systems ◽  
Party Competition ◽  
System Stability ◽  
Informal Institution ◽  
Democratic Experience ◽  
The Stability

The study of political parties and party systems is intimately linked to the development of modern political science. The configuration of party competition varies across time and across polities. In order to capture this variance, one needs to go beyond the analysis of individual parties and to focus on their numbers (i.e. fragmentation), their interactions (i.e. closure), the prevailing ideological patterns (i.e. polarization), and the stability of the balance of power (i.e. volatility) in all spheres of competition, including the electoral, parliamentary, and governmental arenas. Together, these factors constitute the core informal institution of modern politics: a party system. The relevant scholarship relates the stability of party systems to the degree of the institutionalization of individual parties, to various institutional factors such as electoral systems, to sociologically anchored structures such as cleavages, to economic characteristics of the polity (primarily growth), to historical legacies (for example, the type of dictatorship that preceded competitive politics) and to the length of democratic experience and to the characteristics of the time when democracy was established. The predictability of party relations has been found to influence both the stability of governments and the quality of democracy. However, still a lot is to be learned about party systems in Africa or Asia, the pre-WWII era or in regional and/or local contexts. Similarly, more research is needed regarding the role of colonialism or how party system stability affects policy-making. As far as temporal change is concerned, we are witnessing a trend towards the destabilization of party systems, but the different indicators show different dynamics. It is therefore crucial to acknowledge that party systems are complex, multifaceted phenomena.

A Chemism Analysis of Alkali in the Chemical Mechnical Polishing Process of SiC Substrate

2014 ◽  
Vol 1027 ◽  
pp. 208-212
Author(s):  
Jian Guo Yao ◽  
Li Jie Ma ◽  
Su Fang Fu ◽  
Zhan Kui Wang ◽  
Jian Xiu Su
Keyword(s):  
Removal Rate ◽  
Chemical Characteristic ◽  
Material Surface ◽  
Polishing Process ◽  
Organic Bases ◽  
Crystal Substrate ◽  
Ph Modifier ◽  
The Stability

In this study, according to physic-chemical characteristic of the SiC crystals, we analyzed and researched the role of pH modifier in SiC crystal substrate chemical mechanical polishing and the surface after polishing. We used different polish agents which was made up with inorganic and organic bases to experiment, and then analyzed the results. The parameters of the polishing specimen, such as the removal rate of material, surface scanning and the roughness, were analyzed and used to determine the different pH modifiers played different roles in the stability of polish agents and surface quality of the specimen.

scholarly journals Inkjet printing of silk: factors influencing ink penetration and ink spreading

2021 ◽  
Vol ahead-of-print (ahead-of-print) ◽  
Author(s):  
Saira Faisal ◽  
Muhammad Ali ◽  
Sheraz Hussain Siddique ◽  
Long Lin
Keyword(s):  
Inkjet Printing ◽  
Design Methodology ◽  
Marked Effect ◽  
Fractional Factorial ◽  
Printing Process ◽  
Content Type ◽  
Textile Fabrics ◽  
The Right

Purpose Pretreatment of fabric with a number of chemicals and auxiliaries is a prerequisite for inkjet printing. Owing to the rapidly increasing use of inkjet printing for textile fabrics, the study of the effects of process variables on various characteristics of the resulting print has drawn considerable interest recently. The purpose of this paper is to study the effects of different variables associated with the inkjet printing process on the quality of the resulting print. Specifically, the effects of chemicals and auxiliaries used in the pretreatment of the fabric prior to printing and factors such as steaming time were studies. Design/methodology/approach In the present study, which forms a part of a larger study by the authors, the influence of the nature of thickener, the amounts of thickener, urea and alkali, pH of the pretreatment liquor and the duration of steaming on ink penetration into the printed fabrics and the ink spreading across the fabrics was studied. The nature of ink penetration and ink spreading are known to have pronounced effects on the quality and, in turn, the overall appearance of the resulting print. A set of experiments based on a blocked 25–1 fractional factorial design with four centre points were conducted to evaluate the role of the aforementioned five variables. Ink penetration was quantified on the basis of the principles of Kebulka-Munk theory while ink spreading was analysed by image analysis. Findings Detailed statistical analyses of the experimental data obtained show that different thickeners perform differently and can have a marked influence on ink penetration and ink spreading. In the case of polyacrylic acid-based thickener, changing the levels of the factors has a marked effect on ink penetration and in-turn on ink spreading. In the case of polyacrylamide (PAM)-based thickener, on the other hand, the effect of changing the levels of various factors on the ink penetration and ink spreading is considerably less pronounced. In addition, PAM treated samples exhibited better performance in terms of ink penetration and spreading. Originality/value This study provides useful information for textile printers and highlights the importance of selecting the right type of thickener to make the printing process and the quality of the resulting print more predictable and controllable.

scholarly journals THreats and Risk Soft Heparliament Aryregime from Positions of Conservative Traditionalism

2016 ◽  
Vol 3 (4) ◽  
pp. 50-59
Author(s):  
V I Erygina
Keyword(s):  
Law Enforcement ◽  
Critical Theory ◽  
State Power ◽  
Russian Scientist ◽  
Historical Experience ◽  
Successful Solution ◽  
Russian State ◽  
The Stability

The successful solution of modern problems, not only in lawmaking but also in law enforcement fields of development rights depend on the efficiency of credible legislative (representative) bodies of state power, from the quality of their laws. However, the role of Parliament in the Russian system of «vertical of power» is clearly understated that can be justified only by the need to maintain the stability and integrity of the state. In the study, the author tries to understand what the dangers of being a parliamentary regime, whether it threatens the integrity of the Russian state, which contains the apparent and hidden weaknesses. On the basis of the analy- sis of critical theory, developed by the Russian scientist-jurists of conservative direction, who deny parliamentarism, and also taking into account historical experience, the contributor makes conclusions about the need for further improvement of the contemporary representative institutes of the authority.

scholarly journals Role of Zarqa University in Improving the Quality of the Services Provided to the Local Community in Zarqa Governorate

2018 ◽  
Vol 13 (1) ◽  
pp. 192
Author(s):  
Majed Abdel-Mohdi Masadeh
Keyword(s):  
Local Community ◽  
Administrative Staff ◽  
Total Study Population ◽  
Significance Level ◽  
Final Sample ◽  
Study Population ◽  
The Stability ◽  
The University

The study aimed to identify the role of Zarqa university in improving the quality of the services provided to the local community in Zarqa governorate. The study also sought to identify the degree of the university's interest in the quality of its services provided to the local community from the perspective of its employees, and have been using the scientific method, which combines the descriptive method and analytical method, so the researcher designed a questionnaire for this purpose, based on some previous studies related to the study, and the questionnaire included in its final form on (45) paragraph, and was test the sincerity of the instrument and its stability, and the stability coefficient of the total instrument is (0. 867). The study was conducted on the members of the faculty and administrative staff at the Zarqa University (580), due to the study population size is large, the researcher resorted to select a stratified random sample with percentage (25%) of the total study population, where the final sample is (98) member of faculty and administrative. The study found a number of results was the most important: that there were no statistically significant differences at the of significance level (≥ α 0.05), between the responses of the employees of Zarqa University about the role of Zarqa university in improving the quality of the services provided to the local community in Zarqa governorate attributed to some personal and functional characteristics represented by (gender, specialty of faculty, Scientific qualification, and experience years).

Cognitive Health Counseling 40+

2013 ◽  
Vol 21 (1) ◽  
pp. 24-33 ◽  
Author(s):  
Anne Eschen ◽  
Franzisca Zehnder ◽  
Mike Martin
Keyword(s):  
Outcome Variable ◽  
Pilot Phase ◽  
Subjective Memory ◽  
Cognitive Health ◽  
Health Counseling ◽  
Agents Of Change ◽  
Main Outcome Variable ◽  
Further Development

This article introduces Cognitive Health Counseling 40+ (CH.CO40+), an individualized intervention that is conceptually based on the orchestration model of quality-of-life management ( Martin & Kliegel, 2010 ) and aims at improving satisfaction with cognitive health in adults aged 40 years and older. We describe the theoretically deduced characteristics of CH.CO40+, its target group, its multifactorial nature, its individualization, the application of subjective and objective measures, the role of participants as agents of change, and the rationale for choosing participants’ satisfaction with their cognitive health as main outcome variable. A pilot phase with 15 middle-aged and six older adults suggests that CH.CO40+ attracts, and may be particularly suitable for, subjective memory complainers. Implications of the pilot data for the further development of the intervention are discussed.

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