Research on the Effects of Roughness on the Tactile Properties of Rice Straw Particleboard Surface

2020 ◽  
Vol 12 (6) ◽  
pp. 795-801 ◽  
Author(s):  
Xian-Qing Xiong ◽  
Ying-Ying Yuan ◽  
Yi-Ting Niu ◽  
Liang-Ting Zhang
Keyword(s):  
Surface Roughness ◽  
Rice Straw ◽  
Interior Design ◽  
Roughness Parameter ◽  
Chemical Properties ◽  
Mesh Size ◽  
Design Guidelines ◽  
Before And After ◽  
The Difference ◽  
Parameter Values

To explore the effects of roughness on the tactile properties of rice straw particleboard (RSP), the surface roughness and psychological tactile and visual experiments were conducted for RSP substrates with 0.76 g/cm3 and 0.55 g/cm3 densities after sanding with sandpaper (mesh 180#, 360#, and 600#). The effects of different sandpaper types, sanding time, and density of RSP on the surface roughness were analyzed. The experimental results are as follows. The sanding treatment had significant influence on the surface roughness characterization parameters Ra and Rpv of the RSP specimens. Surface roughness differences between the 180# and 360# mesh-prepared samples were obvious. The tactile and visual psychological values of the 360# and 600# mesh-sanded specimens were higher, and the psychological quantities of untreated and 180# mesh-sanded specimens were lower. After comparing the samples with sanding treatment of sandpaper 0∼180#, the change in surface roughness of RSP with a density of 0.76 g/cm3 was smaller than that of the specimen with a density of 0.55 g/cm3. The psychological quantity difference of RSP specimens with a density of 0.55 g/cm3 was evident. When the sanding time was 1 min., the values of the roughness characterization parameters Ra and Rpv increased slightly. After 3 min. sanding, the Ra and Rpv values stabilized. When the sanding time was 5 min, the roughness was essentially unchanged. With the change in sanding time, the measured values of the tactile psychological quantity varied greatly and the measured values of the visual psychology were very close. For the RSP substrates with higher density, the surface roughness was less after sanding with a smoother surface and better tactile properties. There were significant differences between the surface roughness of the RSPs before and after sanding. After manual sanding over the same time span, the surface roughness evaluation parameter values decreased with an increase of mesh size of the sandpaper, and the tactile properties were improved. The longer the sanding time, the smaller the difference in the surface roughness parameter values, and the smaller the difference between the tactile psychological quantity and the visual psychological quantity. To expand the research scope of RSP products, this study investigates not only the physical and chemical properties but also the subjective feelings when using the RSP products. This will provide analytical methods and design guidelines for the consideration of environmental factors in furniture and interior design.

Condition Monitoring Technology for Connecting Part and Sliding Part of Reciprocating Compressor

2017 ◽  
Author(s):  
Yoshifumi Mori ◽  
Takashi Saito ◽  
Yu Mizobe
Keyword(s):  
Mathematical Model ◽  
Natural Frequencies ◽  
Error Function ◽  
Connecting Rod ◽  
Value Analysis ◽  
Before And After ◽  
The Difference ◽  
Bending Modes ◽  
Parameter Values ◽  
The Mathematical Model

We focused on vibration characteristics of reciprocating compressors and constructed the mathematical model to calculate the natural frequencies and modes for crank angles and proposed a method to estimate the degree and the suspicious portion of failure by difference of temporal parameter values obtained using measuring data in operation and the mathematical model. In this paper, according to the proposed method, a case study is carried out using the field data, where the data were acquired before and after the failures occurred in the connecting parts of connecting rod, to prospect the difference between each parameter value for two operating states. Inspecting resonant characteristics each in the frequency response data relating to the natural frequencies for bending modes of the piston rod, we determined two resonant frequencies, which could correspond to the 1st and 2nd mode about bending of the piston rod. To equate the calculated each natural frequency from eigen value analysis based on the proposed model with each resonant frequency, we define the error function for the identified problem, namely optimum problem. In the identified results, it is found that some parameter values have much difference and the corresponding failure could occur around the connecting rod. We could show the possibility to detect both the change of the parameter values and the deterioration parts for two different kinds of the operating states by our proposed method.

AFM Study of Untreated and Treated Fibers of Mongolian Goat Cashmere

2009 ◽  
Vol 610-613 ◽  
pp. 175-178 ◽  
Author(s):  
Namsrai Javkhlantugs ◽  
Enkhbaatar Ankhbayar ◽  
Khishigjargal Tegshjargal ◽  
Damdin Enkhjargal ◽  
Chimed Ganzorig
Keyword(s):  
Surface Roughness ◽  
Atomic Force Microscopy ◽  
Fine Structure ◽  
Ambient Conditions ◽  
Bleaching Process ◽  
Surface Change ◽  
Force Microscopy ◽  
Atomic Force ◽  
Before And After ◽  
The Difference

The morphological surface change of untreated and treated fibers of the Mongolian goat cashmere was investigated by atomic force microscopy (AFM) at ambient conditions. The cuticle scale heights of the Mongolian goat cashmere fibers were measured by the AFM for the fibers before and after treatment. The experimental results showed that the difference between the fine structure of the cuticle and surface roughness of untreated and treated fibers. We found that the surface morphological change of the cashmere fibers was strongly degraded after the bleaching process.

scholarly journals Analysis of Surface Roughness and 3D Scanning Topography of Zirconia Implants Before and After Photofunctionalisation by 3D Optical Profilometry- An Invitro Study

2021 ◽  
Author(s):  
Arunjaikumar Ravindran ◽  
Suma Karthigeyan ◽  
Ramesh Bhat ◽  
Madhulika Naidu ◽  
Senthilnathan Natarajan ◽  
...  
Keyword(s):  
Surface Roughness ◽  
Roughness Parameter ◽  
In Vitro Study ◽  
Control Group ◽  
P Value ◽  
Study Group ◽  
Optical Profilometry ◽  
Before And After ◽  
Zirconia Implants

Introduction: Zirconia is considered as an alternative material for the fabrication of implants. Surface roughness of the implant plays a fundamental role in the initial bone formation. The rationale of using 3D optical profilometry in this study was to evaluate the surface roughness of the zirconia implants before and after Ultraviolet (UV) photofunctionalisation. Also, Moreso 3D optical instruments have a better resolution than the mechanical ones like Atomic Force Microscopy (AFM). Aim: To analyse the surface roughness and topography of zirconia implants after photofunctionalisation using optical profilometry. Materials and Methods: This is an in-vitro study conducted over a period of six months from March 2020 to August 2020. Ten commercially machined Zirconia implants, five each in study and control group, were micro analysed at three different regions (abutment, thread and crest) by optical profilometry. Study group was surface treated by UV radiation for 48 hours. Quantitative morphometric analysis was done between two groups and p-value less than 0.05 was considered statistically significant. The statistical test applied in this study was independent t-test. Results: Scanning micrographs of the study group revealed highest density of summits contributing to increased surface area in the study group. Quantitative analysis of surface roughness showed statistically significant higher mean roughness parameter for photofunctionalised implants in abutment, crest and thread region (p<0.05). Conclusion: Photofunctionalisation is a potentially synergistic technique in producing textured zirconia implants.

scholarly journals Использование модифицированного лигнина для снижения токсичности древесных плит

2018 ◽  
Author(s):  
И.В. Тимофеев ◽  
Д.В. Иванов ◽  
А.А. Леонович ◽  
С.М. Крутов
Keyword(s):  
Specific Surface ◽  
Sorption Capacity ◽  
Urea Formaldehyde ◽  
Medium Density Fiberboard ◽  
Chemical Properties ◽  
Formaldehyde Resin ◽  
Hydrolysis Lignin ◽  
Before And After ◽  
Correlation Processing ◽  
The Difference

Исследованы модифицированные тонкодисперсные препараты гидролизного лигнина как акцепторы формальдегида в технологии древесноволокнистых плит средней плотности. Изучены гидролизный лигнин Кировского биохимического завода, мелкодисперсный лигнин, полученный путём паровзрывной обработки исходного, и ультрадисперсный лигнин, полученный на дисковой мельнице. Разработана методика, позволяющая установить сорбционную способность препаратов лигнина по отношению к формальдегиду. Проведены реакции между лигнином и формальдегидом в водной среде при 100 С в течение 1 ч. Содержание формальдегида в реакционной смеси определяли фотометрически; разницу значений до и после кипячения смеси принимали за количество связанного формальдегида. Методом корреляционной обработки данных установлено, что способность препаратов лигнина связывать свободный формальдегид на 88% зависит от их удельной поверхности. Препарат ультрадисперсного лигнина характеризуется удельной поверхностью 14 м2/г и предпочтительнее других препаратов как акцептор формальдегида. Помимо сорбции имеет место химическое взаимодействие формальдегида и функциональных групп лигнина, что иллюстрируют ИК-спектры, а также спектры твёрдотельного ЯМР. Установлена сорбционная способность акцептора по отношению к формальдегиду, выделяющемуся при отверждении карбамидоформальдегидной смолы. Исследованы физико-химические свойства смолы, совмещённой с препаратом ультрадисперсного лигнина. При изготовлении образцов древесноволокнистых плит проведен факторный эксперимент, позволивший подобрать технологические режимы для получения плит класса эмиссии Е1, соответствующего стандарту на древесноволокнистые плиты. Возможно получение плит класса эмиссии Е0,5, однако необходим повышенный расход лигнина с использованием упрочняющих добавок. Modified preparations of hydrolysis lignin as acceptors of formaldehyde were researched in medium density fiberboard technology. The hydrolysis lignin of the Kirov Biochemical Plant, fine-dispersed lignin, obtained by steam-blasting treatment, and ultra- dispersed lignin, obtained on the disk mill were researched. Method, which can show how lignin sorbs formaldehyde was developed. The reaction between lignin and formaldehyde was carried out in aquatic environment at 100 oC during 1 hour. The difference in values before and after boiling of the reaction mixture was identified as the amount of sorbed formaldehyde. The correlation processing of data established that the sorption capacity of lignin preparations depends on their specific surface by 88%. Ultra-dispersed lignin has specific surface 14 m2/g therefore it’s more effective acceptor. IR spectrums and NMR spectrums of ultra-dispersed lignin were researched after determining their sorption capacity. They showed that formaldehyde came into reaction with functional groups of lignin. It was established that ultra-dispersed lignin can sorb formaldehyde, formed during hardening of urea-formaldehyde resin. The physic-chemical properties of the resin combined with the ultra-disperse lignin were also researched. While making MDF the full factorial experiment was carried out. It allowed to find technological modes for making wood board, which have emission class E1, and corresponds state standard for fiberboard. It is possible to produce wood boards of emission class E0,5, however, increased lignin consumption and use of hardening additives are necessary.

An Enhanced End Milling Surface Texture Model Including the Effects of Radial Rake and Primary Relief Angles

1994 ◽  
Vol 116 (2) ◽  
pp. 166-174 ◽  
Author(s):  
S. N. Melkote ◽  
A. R. Thangaraj
Keyword(s):  
Surface Roughness ◽  
Surface Texture ◽  
End Milling ◽  
Three Dimensional ◽  
Roughness Parameter ◽  
Surface Profile ◽  
Dimensional Structure ◽  
Machined Surface ◽  
Texture Model ◽  
Parameter Values

An enhanced surface texture model for predicting the two- and three-dimensional structure of the surface generated by the end cutting edges on the bottom of an end mill is presented. This model includes the effects of the radial rake and the primary end tooth relief angles which have been neglected in the models available to date. Non-ideal effects such as cutter runout and back-cutting are explicitly modeled. An algorithm to simulate the two- and three-dimensional milled surface is presented. It is shown that the main effect of the radial rake and the primary end tooth relief angles is to increase the surface roughness parameter values. The effectiveness of the enhanced model in accurately capturing the major features of the machined surface texture and in closely predicting the roughness parameter values is demonstrated through experiments and model simulations. It is shown that the enhanced model predicts both the shape of the surface profile and the surface roughness parameters more accurately than the existing models in the literature.

scholarly journals Biopolimeric Nano Structural Compositions Based on Caramelized Honey

2019 ◽  
Vol 20 (4) ◽  
pp. 445-452
Author(s):  
S.А. Кurta ◽  
О.М. Khatsevich ◽  
М.R. Tsap ◽  
D. Ondrušová ◽  
T.M. Gromovy ◽  
...  
Keyword(s):  
Chemical Properties ◽  
Biochemical Properties ◽  
Biologically Active ◽  
Chewing Gum ◽  
Periodontal Tissue ◽  
Active Components ◽  
Biochemical Activity ◽  
Prevention And Treatment ◽  
Before And After ◽  
The Difference

The article deals with chemical properties of honey as well as wax and beeglue before and after the process of caramelization. The research has been done to study chemical reactions of caramelization of honey and other bee products; the biochemical properties of the obtained substances have been investigated as well. It has been revealed that biological activity of the compound after thermochemical heating of honey in the presence of special catalysts was discovered. Infrared spectra, moisture, viscosity, size and distribution of nanoparticles, elemental composition, oxymethylfurfural content, diastase number  of caramelized honey have been investigated. The difference between the sizes of nanoparticles of raw and caramelized honey has been revealed, namely caramelized honey (1.5-2.0 times) of smaller size encourages their biochemical activity. On the basis of the results obtained from caramelized honey, wax and beeglue as well as their properties, the chewing gum with biologically active components for the prevention and treatment of periodontal tissue diseases (gingivitis, periodontitis and periodontal disease) was invented. Clinical studies on chewing gum with honey, wax, and beeglue have confirmed that it provides health benefits among 72 % of patients.

scholarly journals Minimization Method for 3D Surface Roughness Evaluation Area

Machines ◽  
2021 ◽  
Vol 9 (9) ◽  
pp. 192
Author(s):  
Viktor Molnár
Keyword(s):  
Surface Roughness ◽  
Surface Area ◽  
Roughness Parameter ◽  
Industrial Applications ◽  
Minimization Method ◽  
3D Surface ◽  
3D Surface Roughness ◽  
Roughness Evaluation ◽  
Parameter Values ◽  
The Relationship

3D surface roughness measurement is still a less mature procedure than its 2D version. The size of the evaluation area is not as standardized as the measurement length in the 2D version. The purpose of this study is to introduce a method for minimizing the evaluated surface area. This could help industrial applications in minimizing the time and cost of measurements. Machining experiments (hard turning and infeed grinding) and surface roughness measurements were carried out for automotive industrial parts to demonstrate the introduced method. Some frequently used roughness parameters were analyzed. Basic statistical calculations were applied to analyze the relationship between the surface area and the roughness parameter values and regression analyses were applied to validate the results in case of the applied technological data. The main finding of the study is that minimum evaluation areas can be clearly designated and, depending on the different roughness parameter–procedure version, different evaluation sizes (Sa: 1.3 × 1.3 mm; Sq: 1.4 × 1.4 mm; Ssk and Sku: 2 × 2 m; Sp and Sv: 1.7 × 1.7 mm) are recommended.

Effects of Germanium on Grain size and surface roughness of the solid phase crystallized polycrystalline Si1−xGex films

1996 ◽  
Vol 424 ◽  
Author(s):  
Jin-Won Kim ◽  
Myung-Kwan Ryu ◽  
Tae-Hoon Kim ◽  
Ki-Bum Kim ◽  
Sang-Joo Kim
Keyword(s):  
Activation Energy ◽  
Surface Roughness ◽  
Grain Size ◽  
Solid Phase ◽  
Chemical Vapor ◽  
Germanium Content ◽  
Capping Layer ◽  
Before And After ◽  
Pressure Chemical ◽  
The Difference

AbstractSi1−xGex (x≤0.5) films were deposited by using Si2H4 and GeH4 source gases in a low pressure chemical vapor deposition (LPCVD). The deposition temperature was varied from 375 °C for Si0.5Ge0.5 to 450 °C for Si film in order to deposit amorphous Si1−xGex films and the deposition pressure was about 1 Torr. The grain size of polycrystalline Si1−xGex films made by solid phase crystallization (SPC) decreases with germanium content in the films, and the activation energy obtained from the dependence of grain size on annealing temperature was 0.4 eV for Si and 0.45 eV for Si0 69Ge0.31. From obtaining a similar activation energy irrespective of Ge content in the film, the decrease of grain size with germanium content is attributed to the difference of the asdeposited film conditions. The surface roughness of Si1−xGex films investigated by atomic force microscope (AFM) increases with germanium content in the film before and after SPC. For instance, the root-mean square (rms) values of the surface roughness of the as-deposited Si and Si0.5Ge0.5 films were 2.3 and 17 Å, while those values were increased to 2.6 and 41 Å, respectively, after SPC. In order to reduce the surface roughness of Si0.5Ge0.5 film, we have deposited a thin Si capping layer on top of the Si1−xGex layer and identified that this capping layer effectively reduces the increase of surface roughness after SPC.

scholarly journals Cutting Speed and Feed Influence on Surface Microhardness of Dry-Turned UNS A97075-T6 Alloy

2020 ◽  
Vol 10 (3) ◽  
pp. 1049 ◽  
Author(s):  
Sergio Martín-Béjar ◽  
Francisco Javier Trujillo Vilches ◽  
Carolina Bermudo Gamboa ◽  
Lorenzo Sevilla Hurtado
Keyword(s):  
Surface Roughness ◽  
Thermal Effects ◽  
General Trend ◽  
Cutting Speed ◽  
Cutting Parameters ◽  
Corrosion Process ◽  
Surface Microhardness ◽  
Before And After ◽  
Dry Conditions ◽  
Parameter Values

In this work, an analysis of the cutting speed and feed influence on surface roughness and microhardness of UNS A97075-T6 alloy, turned under dry conditions, was carried out. The results were compared before and after a corrosion process. The influence of these cutting parameters on each of these variables was analyzed, as well as the possible interrelation between them. The microgeometrical deviations showed a general trend to increase with feed. However, no significant modifications were observed as a function of the cutting speed. This trend was softer after the corrosion process, due to the surface alterations produced by pitting corrosion, which resulted in higher dispersion of the experimental data. In addition, a surface microhardness increment was observed in all samples, after machining and before corrosion, regardless of the cutting parameter values. The experimental results revealed that the mechanical effects, produced by the feed, should not be neglected against the thermal effects, produced by the cutting speed, within the range of the tested cutting speed. Finally, the corrosion process negatively affected the microhardness, but it was not possible to establish a direct relationship between the cutting parameters, surface roughness, and microhardness after a corrosion process.

Analysis of sliding friction of WC-Co composite on particleboard

2020 ◽  
Vol 111 ◽  
pp. 60-67
Author(s):  
Jacek Wilkowski ◽  
Marek Barlak ◽  
Radosław Jałocha ◽  
Zbigniew Werner ◽  
Alicja Auriga
Keyword(s):  
Surface Roughness ◽  
Friction Coefficient ◽  
Coefficient Of Friction ◽  
Sliding Friction ◽  
Roughness Parameter ◽  
Average Increase ◽  
Average Coefficient ◽  
Before And After ◽  
The Coefficient Of Friction ◽  
Nano Size

Analysis of sliding friction of WC-Co composite on particleboard. The paper presents the analysis of the coefficient of friction at the contact area between WC-Co composite and particleboard. The four types of WC-Co composite in the form of milling indexable knives for wood materials machining were tested. The tests were carried out on a linear reciprocating tribotester (pin-on-flat), where the sample was the clearance surface of WC-Co indexable knives and the counter-sample was made of three-layer particleboard. Before and after tribological tests, the surface roughness of tested knives was measured. The highest values of friction coefficient were obtained for the type UMG04 of cemented carbide - with nano size of WC grains and the lowest content of cobalt. The average coefficient of friction for selected types of WC-Co correlated with the average increase in surface roughness (the roughness parameter Ry).

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