Energy consumption of milking pump controlled by frequency convertor during milking cycle

ArticleThe article deals with selected parameters affecting the energy consumption of a vacuum pump in a milking system during the whole milking cycle in variants with and without regulation by a frequency convertor. When put into practice, the latest research of creation, control and stabilization of vacuum in milking devices allows dairy farmers to obtain a vacuum system that ensures maximum stability of milking pressure, which is a basic requirement affecting the health of dairy cows. The choice of vacuum system prioritizes in particular high performance, maximum operational reliability, minimum maintenance, long service life, environmental friendliness and economy. The vacuum pump was a Roots vacuum pump with a rotary piston which is typical for this use. Use of a frequency convertor significantly affected the efficiency of this pump for control of vacuum pressure level and pump performance by varying the rotation frequency according to the actual airflow requirement. Using this control system, only as much vacuum pressure is produced as necessary. By measurement of an experimental setup, it was found that the average power requirement of a setup with a control valve was 3.8 kW compared to 1.7 kW in the case of the variant with frequency convertor. Measurements and calculations have shown that this system is capable of saving more than 50% of electric energy

The Fourteenth Data Release of the Sloan Digital Sky Survey: First Spectroscopic Data from the extended Baryon Oscillation Spectroscopic Survey and from the second phase of the Apache Point Observatory Galactic Evolution Experiment

The fourth generation of the Sloan Digital Sky Survey (SDSS-IV) has been in operation since July 2014. This paper describes the second data release from this phase, and the fourteenth from SDSS overall (making this, Data Release Fourteen or DR14). This release makes public data taken by SDSS-IV in its first two years of operation (July 2014-2016). Like all previous SDSS releases, DR14 is cumulative, including the most recent reductions and calibrations of all data taken by SDSS since the first phase began operations in 2000. New in DR14 is the first public release of data from the extended Baryon Oscillation Spectroscopic Survey (eBOSS); the first data from the second phase of the Apache Point Observatory (APO) Galactic Evolution Experiment (APOGEE-2), including stellar parameter estimates from an innovative data driven machine learning algorithm known as "The Cannon"; and almost twice as many data cubes from the Mapping Nearby Galaxies at APO (MaNGA) survey as were in the previous release (N = 2812 in total). This paper describes the location and format of the publicly available data from SDSS-IV surveys. We provide references to the important technical papers describing how these data have been taken (both targeting and observation details) and processed for scientific use. The SDSS website (www.sdss.org) has been updated for this release, and provides links to data downloads, as well as tutorials and examples of data use. SDSS-IV is planning to continue to collect astronomical data until 2020, and will be followed by SDSS-V.Comment: SDSS-IV collaboration alphabetical author data release paper. DR14 happened on 31st July 2017. 19 pages, 5 figures. Accepted by ApJS on 28th Nov 2017 (this is the "post-print" and "post-proofs" version; minor corrections only from v1, and most of errors found in proofs corrected

The Fourteenth Data Release of the Sloan Digital Sky Survey: First Spectroscopic Data from the Extended Baryon Oscillation Spectroscopic Survey and from the Second Phase of the Apache Point Observatory Galactic Evolution Experiment

The fourth generation of the Sloan Digital Sky Survey (SDSS-IV) has been in operation since 2014 July. This paper describes the second data release from this phase, and the 14th from SDSS overall (making this Data Release Fourteen or DR14). This release makes the data taken by SDSS-IV in its first two years of operation (2014–2016 July) public. Like all previous SDSS releases, DR14 is cumulative, including the most recent reductions and calibrations of all data taken by SDSS since the first phase began operations in 2000. New in DR14 is the first public release of data from the extended Baryon Oscillation Spectroscopic Survey; the first data from the second phase of the Apache Point Observatory (APO) Galactic Evolution Experiment (APOGEE-2), including stellar parameter estimates from an innovative data-driven machine-learning algorithm known as "The Cannon"; and almost twice as many data cubes from the Mapping Nearby Galaxies at APO (MaNGA) survey as were in the previous release (N = 2812 in total). This paper describes the location and format of the publicly available data from the SDSS-IV surveys. We provide references to the important technical papers describing how these data have been taken (both targeting and observation details) and processed for scientific use. The SDSS web site (www.sdss.org) has been updated for this release and provides links to data downloads, as well as tutorials and examples of data use. SDSS-IV is planning to continue to collect astronomical data until 2020 and will be followed by SDSS-V

Comparison of Reliability of Vth and VIth Generation Adhesive Systeme by Thermocycling

The target of the thestudy was to compare the reliability of adhesive systems of Vth. and VIth generation by thermocycling according to method ISO/TS 11405:2003 (E). For comparison there were chosen two representatives from each group - from the Vth generation materials Single Bond Adper and Prime&Bond NT and from the VIth generation materials Prompt-L Pop Adper and Xeno III. The materials of the Vth generation were combined with advised etching gels and by all adhesives the directions for use were strictly followed. Adhesive systems were combined with material Spectrum TPH. Each adhesive system was tested on 10 samples of intact third molars. The results showed extensive variability among reliability single adhesives without dependence to generations, that means self-etch or conventional total-etch. While measuring microleakage according to ISO/TS 11405:2003 (E) was the most reliable Prime&Bond NT, with score 12, than Xeno III with score 26. Between reliability of Single Bond Adper (score 37) and Prompt L-Pop Adper (score 38) there was no significant difference. The results demonstrated no significant difference between single generations of adhesive systems and proved that the quality of each product is the most important, whether it belongs to self-etch or conventional total-etch generations

Long-term Durability of Composite Restoration Margins in Enviroments with Increased Corrosion Risk

Introduction: An adhesive bond between hard dental tissues and composite reconstructions is exposed to mechanical load, water, bacteria, enzymes and different chemical compounds. These factors could impair durability and resistance of composite reconstructions. In contrast with extensive research of negative influence of water on degradation of adhesive bonds, the influence of chemical substances on adhesive bond has not been investigated to a greater extent. Aim: The aim of the experimental part of the thesis was to evaluate the influence of hydrogen peroxide containing tooth-whitening products and mouth rinses containing chlorhexidine and fluoride on a long-term stability of class V composite restorations created using four contemporary adhesive systems by a microleakage method. Materials and methods: The following adhesive systems were investigated: total-etch Gluma Comfort Bond (GLU), and self-etch adhesives Clearfil SE Bond (CLF), Adper Prompt (ADP) and iBond (IBO). Standardized class V cavities were prepared in 192 extracted human teeth (one cervical margin in the cementum and one in the enamel). Subsequently, the cavities were restored using microhybride composite Charisma. The specimens were then exposed to the tooth whitening system Opalescence PF 20, mouth rinse Corsodyl containing chlorhexidine and mouth rinse Elmex containing aminfluoride. The exposure times were 2 and 6 months, the whitening system was applied in 25 cycles each 8 hours apart. The control group included restorations exposed to distilled water for 24 hours, 2 and 6 months. After the exposure the specimens were immersed in 2% methylene blue solution for 24 hours. The microleakage data were analyzed using Kruskall-Wallis, Mann-Whitney and Wilcoxon tests (p = 0.05). The surface morphology was assessed using scanning electron microscopy. Results: After being exposed to water, the specimens bonded by GLU a CLF showed a significantly lower microleakage score in both enamel and dentine. ADP and IBO showed a significantly higher microleakage, especially in the enamel. Compared to the control group, there were only small and statistically insignificant changes in the dentine and enamel microleakage. Differences were observed, when the samples were exposed to chlorhexidine- and fluoride-containing mouth rinses. Compared to the control group, there were statistically significantly lower microleakage scores, particularly for ADP and IBO. Conclusions: The results suggest that the risk of impairment of the adhesive bond stability is higher in self-etch adhesive systems with simplified application procedures. The insignificant effect of the peroxide tooth whitening system and the unexpected increase in resistance of restorations exposed to mouth rinses inevitably lead to certain doubts about appropriateness of the recommended microleakage tests for systems with different bond to the enamel and dentin. Thus, it remains unclear if the tested products for oral hygie-ne really increased the adhesive bond resistance, or the observed effect resulted from the microleakage reduction due to precipitation of components of the exposure media

What are Future Curing Lights Technology Trends?

Over the recent years, dental curing lights as well as light-cured materials have been undergoing rapid development, which makes choosing a curing light guaranteeing the optimal polymerization degree difficult. The paper summarizes critical characteristics of curing lights necessary for reliable polymerization of light-cured composite materials, glass-ionomer cements and adhesive systems with different types of photoinitiators. The effect of emission-spectrum width on the polymerization degree of composite material is documented with polymerization of two typical composite materials with different photoinitiators and light-cured using quartz-tungsten-halogen lamp and LED lights with narrow and wide emission band. Values of surface Knoop hardness numbers revealed that among currently available curing lights, in particular LED with two or more types of diodes emitting broad-range blue light achieve the versatility and efficiency of halogen lights, currently the gold standard in light curing

Effect of Peroxide Bleaching Systems on the Marginal Integrity and Surface Hardness of Composite Restorations

Peroxide bleaching systems may affect resin composite restorations through their strong oxidative effect. The objective was to investigate the influence of bleaching systems on long-term stability of marginal integrity of composite restorations and composite surface resistance. Class V cavities were prepared at the enamel-dentine junction and filled using a total-etch adhesive system Gluma Comfort Bond (n=36) and self-etching adhesive iBond (n=36) in combination with the microhybrid resin composite material Charisma. The peroxide bleaching gel Opalescence PF 20% (20 wt. % carbamide peroxide) was applied 25 times on the restorations. The control groups were exposed to distilled water for 24 hours and two months before a microleakage test was performed. Composite hardness was characterized after 0, 2, 7, 14 and 25 applications of the gel and compared with the control group (each n=5) exposed to distilled water for two months. Surface morphology was evaluated using scanning electron microscopy. After the gel application no significant changes in marginal integrity were found for both groups of samples. With Gluma Comfort Bond due to its high bonding performance and with iBond due to its decreased performance on enamel causing marginal integrity failure at the beginning of the experiment. On the other hand, pronounced surface porosity and decreased hardness of the composite material indicated its significant degradation in the presence of the bleaching gel

The Effect of Disinfectants on the Properties of Dental Impression Materials

Introduction: The disinfection of dental impressions is necessary in terms of preventing the transmission of infection from patients' blood or saliva before processing at a dental office or laboratory. The adverse effects of the disinfection process can result in dimensional changes of the dental impressions, a change in surface quality and loss of the ability to reproduce the details of hard and soft tissues in the oral cavity. All these potential negative effects can ultimately influence the final prosthetic work. Aim: This study aimed to assess "in vitro" the impact of several commercially available disinfectants on detail reproduction and the dimensional changes of dental impressions made from various types of dental impression materials and their compatibility with dental gypsums. Methods: In this study alginate (Ypeen, Alligat fast set, Elastic Cromo) and elastomer (Variotime Medium Flow, Xantropren L blue, Impregum Soft) dental impression materials in combination with four disinfectants (Aseptoprint Liquid, Zeta 7 solution, Silosept, Dentaclean Form ) and gypsums type 3 (Mramorit Blue) and type 4 (BegoStone plus) were tested. The methods were executed using technical standards ČSN EN 21563 Dental alginate impression materials and ČSN EN ISO 4823 Dental elastomeric impression materials. Detailed reproduction of the dental impressions, their dimensional changes and compatibility with gypsum were evaluated on the impressions of the metal block with lines of defined dimensions. Dimensional change was defined as the percentual change of the distance between lines reproduced on disinfected impressions and the lines of defined dimensions on the metal block. The results were statistically analysed using Statistica 12 software (StatSoft Inc., Tulsa, USA). Two-factor and one-factor analysis of variance ANOVA with Tukey HSD post-hoc tests at the significance level of 0,05 % were used. Results: The detail reproduction of dental impressions and their compatibility with gypsum worsened when the alginate impression materials were combined with disinfectant Dentaclean Form. The surface of other tested impression materials remained unchanged after disinfection, as were the reproduction of details and compatibility with gypsum. Dimensional changes after disinfection were the highest in alginate material Elastic Cromo and the shortest in polyether material Impregum Soft. Conclusion: The disinfection of dental impressions is currently a necessary step before further processing in dental laboratories. However, it was confirmed that the desired properties of impressions may be negatively affected by disinfectant, particularly in the case of alginate materials. It is therefore always important to approach the selection of specific disinfectant with respect to the manufacturer's recommendations and the available information regarding this issue

Comparison of Curing Efficacy of Halogen and LED Polymerization Lamps Using Composite Materials of Different Polymerization Mechanism

The objective was to compare efficacy of several types of halogen and LED polymerization lamps in curing restorative composite materials. Halogen lamps Heliolux DLX1 (Ivoclar Vivadent) and Megalux Fast Cure (MegaPhysik) and LED lamps DioPower (CMS Dental), Translux Power Blue (Heraeus Kulzer), BluePhase C8 (Ivoclar Vivadent) of a narrow spectral emission (group LED 1) and G-Light (GC, USA) and BluePhase G2 (Ivoclar Vivadent) of a broad spectral emission (group LED 2) were used. Curing efficacy was evaluated by measuring the composite hardness on the top irradiated and bottom not-irradiated surfaces of 2 mm thick specimens prepared from radically initiated dimethacrylate-based composite material Charisma (Heraeus Kulzer) and epoxy-based cationically polymerized composite material Filtek Silorane (3M ESPE). In curing of both composite materials a significant effect of the polymerization lamp on composite hardness and hence, polymerization degree was observed. The highest hardness of the composite material Charisma was found after polymerization with the halogen lamps and also BluePhase G2 of a broad spectral emission. With the epoxy-based Filtek Silorane the highest surface hardness was reached with both LED 2 and halogen lamps. In spite of limited number of polymerization lamps tested it seems obvious that the highest polymerization degree can be reached with polymerization lamps of broad spectral emission, such as high-power halogen lamps or LED lamps equipped with diodes emitting light in a short wavelength range