bluuebunny/crossref_metadata_2025_split huggingface dataset:
Friction Phenomenon Study For the Chain Link – Pin Joint
Authors: Gavrila C C , Lates M T 
Published: January 2020

Abstract
The friction inside the automobile mechanical transmissions leads to a large influence of the classic fuel consumption and also to the environment impact. Actually, the chain drive is one of the most important transmission inside a car and has few friction sources inside, as the properly chain friction between its components (links, pins), the friction between the chain links and the sprockets and also the friction between the chain links and the tensioning guide active part. The paper main objective is to study the friction phenomenon in the chain link – pin contact for different loads. The tests are achieved for different sets of motion rotational speeds and normal loads; so according to these, there are determined the dynamic friction coefficient (during the motion) and the static friction coefficient (at the stroke ends). The results led to the static and dynamic friction coefficient variation, with the motion rotational speed and the normal loading force. In the final part, the conclusions are presented.
Comparative study of the friction phenomenon in the contact between the guide and the bush and silent chain links
Authors: Lates M T , Gavrila C C 
Published: January 2020

Abstract
The optimisation process of the chain drives includes the development of new chain links in order to reduce the noises, the vibrations and the non-linearity of the motions. One solution is the development of the silent chains in order to replace the bush chains. According to the literature, the silent chains have a better dynamic behaviour instead of bush chains but there are only few studies regarding their frictional behaviour. As part of the global friction in a chain drive transmission, the paper presents an experimental comparative study of the friction between a PA46 polyamide material (used to manufacture the active part of the tensioning guide) and the bush chain and silent chains respectively. The tests are performed on a tribometer by considering different rotational speeds, local pressures and temperatures. The results are presented as variations of the dynamic and static friction coefficients depending on the test parameters. Finally there are offered conclusions regarding the practical applications of the results.
Wear’s issues on high-pressure common rail pumps
Authors: Iordache R C , Petrea N D , Bujoreanu C 
Published: January 2020

Abstract
High-pressure pumps are the most important components of modern fuel injection systems. A modern system is the common rail one, equipping vehicles with a diesel or a gasoline engine. Depending on the fuel type, the design of the pumps is completely different, and it is more complex for diesel engines that are more prone to wear. The components subjected to wear are those in contact and continuous motion like drive shaft with roller and shoe, plunger and hydraulic head assembly with valves. Wear is initiated as a result of a process and product deviations or inadequate exploitation of the high-pressure pump. The factors influencing the wear can be improper material hardness, improper coating, incomplete or wrong machining, wrong clearance or misalignment between components, inadequate surface finish, dimensions out of tolerances, wrong assembly process, poor lubrication, contamination or running at high loads and temperatures. Our paper aims to identify, describe and discuss the types of wear encountered at common rail high-pressure pumps, highlighting the effects on their functionality. The wear occurrence can be prevented by paying more attention to the design details, manufacturing processes and correct exploitation of the high-pressure pumps.
Determining the tribological properties of different 3D printing filaments
Authors: Maries I-T , Vilau C , Pustan M S , Dudescu C , Crisan H G 
Published: January 2020

Abstract
The paper aims to determine the friction coefficient and wear behaviour of different 3D filaments in contact with a metallic disc. The method used for testing was the pin-on-disc method, where 3D half inch diameter pins with a half sphere end were printed out of the different filaments and rotated on the disc. The optimal time for measuring the friction coefficient was determined by observing when a sudden change in friction was recorded by the sensor as a result of material deposition on the disc. All filaments were tested for the same amount of time using the same normal loads. The friction behaviour was monitored and the mass wear was determined by weighting the spheres before and after each test. The research work of this paper was orientated to determine which 3D printing filament is most suitable for building different parts that come in contact with one another such as parts for creating an innovative 3D printed smart shoes sole.
Comparative study on the behaviour of a serial robot RRR and hand-arm human systems
Authors: Cristea A. F. 
Published: January 2020

Abstract
The paper creates a preamble in the comparative study regarding the loading of vibrations on a robotic system RRR or 3R and hand-arm homologous system. In this study, vibration measurements and comparative analyze are conducted for the two systems, trying to correlate similarities between them, but of the different scale.
Some considerations regarding the influence of working conditions on the corrosion wear of the injection water treatment plant equipment
Authors: Dudu C , Drumeanu A C , Ripeanu R G , Dinita A 
Published: January 2020

Abstract
One of the methods used for the secondary exploitation of oil deposits is the water injection. The injected water is obtained after the separation of the well extracted fluid that contains a mixture of crude oil, water, gases and solid particles. Prior to injection, water must meet the following requirements: a high degree of purity obtained thought the lowest possible mechanical and oil content; lower degree of aggressiveness (corrosion); the highest stability; compatibility with the fluids and minerals in the reservoir formation; low oxygen content and bacteria. The fulfilment of these requirements must be ensured by the water treatment plant whose equipment is subjected to corrosion wear. The equipment degradation are occurring mainly at pipelines and connecting elements of the flotation skid, in the form of advanced corrosion wear because the water injection contains an inconsistent composition mixture of dissolved gases, hydrocarbons, solid particles. The paper presents the regression analyses that emphasize the influence of chemical water composition and fluid speed on the corrosion rate of the different equipment parts. The corrosion rates were obtained using metallic samples according with the NACE SP0775-2013 standard that were placed in different points of the plant. The paper results can be used both at the water plant exploitation and also to next studies concerning the effectiveness of the corrosion inhibition on the corrosion rate.
Erosion modelling: a systematic review of available models and equations
Authors: Lospa A M , Ripeanu R G , Dinita A 
Published: January 2020

Abstract
Across the years there was an increased attention drawn by erosion modelling, both as a general approach and also towards pipeline applications (with a concentration on pipe bends). Several authors have studied the phenomena and tried to explain the mechanisms and factors affecting the emergence and magnitude of erosion. Most of the proposed models and equations were developed for ductile materials, with a smaller part looking also at brittle materials. There are several differences observed, starting with the proposed wear mechanism and continuing with the parameters used in the equations as significant factors (for the erodent particles, target material and working conditions). The most important models and equations are analysed and presented in this article and a systematic visual representation is used to ease and simplify the understanding of the erosion modelling evolution across the years (erosion modelling in general conditions, empirical erosion modelling in pipes and bends, CFD erosion modelling in pipes and bends).
The Effect of Working Parameters upon Oil-Lubricated EHD Contacts Subjected to Load Variation
Authors: Zhang X , Glovnea R 
Published: January 2020

Abstract
The technique of optical interferometry incorporated within a ball-on-disc apparatus has been widely used in the field of the experimental research in thin-film lubrication for approximately the past five decades. This paper presents the theoretical analysis of the dynamic response of an optical interferometry based experimental rig adapted for non-steady work. The dynamic response of the rig was analytically modelled as a three-degree of freedom, forced harmonic vibrating system with damping. Quantitative evaluation of damping of EHD contact was not one of the objectives of this paper, but the results obtained showed the opportunity to try a rather qualitative analysis. The aims of this experimental study are to investigate the effect of entrainment speed and overall film thickness on the oil film thickness of an EHD contact subjected to load cyclic variation. Experimental tests were carried out using different type of base oils with various viscosity. The behaviour of the EHD films was studied and analysed under forced harmonic load vibrations with frequency up to 100 Hz. The tests performed with lubricants of lower viscosity have shown that deviations from steady state film thickness become less and less pronounced as the viscosity of the lubricant decreases. When the amplitude of the oscillatory motion is significantly larger than the deformations of the surfaces under loading, it was observed that fluid entrainment is less important and film squeeze plays the dominant role in the film behaviour.
Factors Influencing the Triboelectric Charging of Granular Plastics in a Rotating-cylinder-type Tribocharger
Authors: Achouri I E , Zeghloul T , Medles K , Richard G , Dascalescu L 
Published: January 2020

Abstract
The electric charging of granular plastics in view of their electrostatic separation is one of the major industrial applications of the triboelectric phenomenon. The granules get charged by collisions and frictions with each-others and with the walls of the tribocharging device. In electrostatic separation applications, the granules of a mixture must be sufficiently charged to be attracted by electrodes of opposite polarity for their separation by type of material. The objective of the present work is to study the effects of three factors that influence the triboelectric charging of polycarbonate granules (size: 2 mm to 5 mm) originating from waste electric and electronic equipment in a rotating-cylinder-type device: particle residence time, cylinder inclination and its rotation speed. The performance of the triboelectric charger was evaluated by measuring the charge per mass ratio of the granules collected at the outlet of the device.
A study for an aluminum electro-thermally actuated U-shaped microtweezer
Authors: Voicu R-C , Pustan M , Birleanu C , Gavrila R , Romanitan C , Tutunaru O , Cismaru A 
Published: January 2020

Abstract
In this paper we present the investigations of two aluminium layers with different thicknesses in order to be used for manufacturing of MEMS and the design, simulation, fabrication and characterizations of a microtweezer designated for micromanipulation applications. Electro-thermo-mechanical finite-element simulations were performed in order to describe the behaviour of MEMS devices. The microtweezers have been fabricated in aluminium, as structural material, by surface micromachining processes. Different characterizations of the structural material by Atomic Force Microscope (AFM), X-ray Diffraction System (XRD) and Scanning Electron Microscopy (SEM) characterization tools were presented.
Research Concerning the End-effectors for SiMFlex Microgripper
Authors: Noveanu S , Rusu C , Rancea C , Lateş D 
Published: January 2020

Abstract
In this paper the SiMFlex microgripper are designed and modelled. The result for FEM analysis for SiMFlex was presented. The prototype for SiMFlex microgripper is realized with non-conventional technologies and the design included flexure hinges and piezoelectric actuators. A study for different surface qualities for end-effectors is presented and used two materials for active parts of jaws manufactured. Simulations and experimental part were generally performed on the system and special attention was given to jaws that were illustrated and clarified by these studies. Based on the results obtained the optimization solutions for end-effectors for SiMFlex microgripper will be realize.
Experimental investigation and optimization of abrasive wear characteristics of polypropylene nanocomposites
Authors: D Jafrey Daniel , K Panneerselvam 
Published: January 2020

Abstract
The applications of the polymer nanocomposites are increasing to a greater extent in several sectors. In this investigation, the matrix selected was Polypropylene (PP) and reinforcing filler was Cloisite 30B (C3B) with Elvaloy-AC-3427 (EAC) as a compatibilizer. Twin screw extruder was used for manufacturing of PP/C3B/EAC nanocomposites. C3B was added at the range of 1, 2, 3, 5 wt% to PP matrix. The manufactured composites was analysed for mechanical and thermal characterization. The tribological characteristics of manufactured nanocomposites were studied using abrasive wear tests. The input parameters considered for the abrasive wear tests were (i) load, (ii) C3B and (iii) sliding distance. The output parameters for the abrasive wear tests were weight loss, Coefficient of Friction (COF) and Specific Wear Rate (SWR). Grey relational analysis and grey fuzzy were done for the optimisation of abrasive wear characteristics. Analysis of Variance (ANOVA) was used for analysing the effect of input parameters over the output factors. Finally, the abraded wear samples of PP/C3B/EAC nanocomposites samples were examined microscopically.
Growth and characterization of halogen substitution in counter benzenesulfonate of organic nonlinear optical crystal : DASB
Authors: You Fei , Teng Fei , Huang Chen , Yu Zhe , Chen Dong , Xia Lihua , Cao Lifeng , Teng Bing 
Published: January 2020

Abstract
The organic stilbazolium derivative crystal4-dimethylamino-N′-methyl-4′- stilbazolium p- bromobenzenesulfonate (DASB) was successfully grown by spontaneous nucleation method coupled slow evaporation (SNM-SE) for the first time. The corresponding powder XRD revealed the crystalline nature of the DASB material, and various functional groups were determined by FT-IR. The thermal stability and melting point were analyzed by TG/DTG and DSC measurement. The absorption coefficient, band gap energy, cut-off wavelength and extinction coefficient were obtained through UV–vis-NIR spectral study. Photoluminescence result indicates DASB crystal exists purple emission at 405 nm and 467 nm because of the π–π* and defect transitions, respectively. The SHG efficiency of DASB crystal is about 3 times higher than KDP crystal. All the encouraging results indicate the DASB crystal is a promising candidate for the Thz generation applications.
Characteristics of a novel thermal-induced epoxy shape memory polymer for smart device applications
Authors: Cui Hao , Tian Wenchao , Kang Yu , Wang Yongkun 
Published: January 2020

Abstract
With the increasing demand for the application of electronic technology, high performance, multi-function and intelligent control have been the main developing trend of smart material. In this paper, a novel thermal-induced epoxy shape memory polymer (ESMP) is developed and utilized as substrate material for smart flexible electronic device. Owing to the advantage of thermal-induced ESMP, circuit substrate can be rigid-flexible controllable at different working temperature. Firstly, the ESMP samples are prepared and then the mechanical and shape memory characteristics are studied respectively. Secondly, the mechanical behaviors are analysed based on thin plate deflection theory and finite element simulation software on the engineering application. Meanwhile, corresponding experimental tests are designed and performed to corroborate the theory and simulation results. At last, ESMP based test circuit board is designed and manufactured. The electrical signals under large deformation are also measured and compared with typical circuit board. The results show that the prepared ESMP, as a smart material, has good reliability, flexibility and great application prospects in the field of intelligent devices.
Solution combustion synthesis of calcium aluminate nanocomposite using coffee husk extract as green fuel and its application in adsorptive amputation of anionic dyes
Authors: Murthy T P Krishna , Gowrishankar B S , Chandraprabha M N , Krishna R Hari 
Published: January 2020

Abstract
Solution combustion synthesis of calcium aluminate (CaAl2O4) nanocomposite using coffee husk extract and its adsorption capacity for removal of Congo red (CR) and Indigo carmine (IC) are reported. Physiochemical properties of adsorbent were studied by PXRD, SEM, TEM and point of zero charge. Batch adsorption studies were conducted to study the effect of adsorbent dosage, pH, contact time, initial dye concentration and temperature on adsorption efficiency of coffee husk derived calcium aluminate nanocomposite (CHCA). Among the isotherms used, Langmuir model explained best the equilibrium data and the maximum monolayer adsorption capacity was found to be 377 and 135 mg/g for CR and IC, respectively. Mass transfer analysis indicated adsorptive removal of dyes was controlled by both external and internal diffusion. Pseudo-first-order model fitted best with experimental kinetic data and adsorption efficiency increased with an increase in the initial bulk concentration of CR and IC. Thermodynamic analysis indicated that adsorption of CR and IC on CHCA is feasible, spontaneous and exothermic in nature. The magnitude of enthalpy and heat of adsorption suggested that the adsorption is physical in nature. The present study explores the potential of coffee husk extract, an agro-based bio-waste, as a novel and eco-friendly fuel in the synthesis of CHCA and the synthesised nanocomposite as a potential adsorbent for the removal of synthetic dyes.
Adsorption and kinetic study of Cr(VI) on ZIF-8 based composites
Authors: Begum Javaria , Hussain Zakir , Noor Tayyaba 
Published: January 2020

Abstract
In this study, adsorption of hexavalent chromium has been examined on ZIF-8 and its various composites. ZIF-8 was modified by using amine groups, GO and Mg(OH)2/GO. ZIF-8, Mg(OH)2/GO, ZIF-8/NH2, ZIF-8/Mg(OH)2/GO, ZIF-8/NH2/GO and ZIF-8/NH2/Mg(OH)2/GO was studied for Cr(VI) adsorption Several characterization techniques were used for the structural and surface characterization such as Fourier transform infrared spectroscopy (FTIR), x-ray diffraction (XRD), scanning electron microscopy (SEM), and Brunauer–Emmett–Teller (BET) surface area analyzer. The impact of various adsorption parameters (contact time, pH, initial concentration of Cr(VI) and absorbent dosage) was studied in batch experiments. Different kinetic and isotherm models were applied on equilibrium data. The adsorption process of ZIF-8 and its composites was explained by pseudo-second-order kinetic model as well as Langmuir isotherm, with maximum removal efficiency of 98% for Cr(VI) by ZIF-8/NH2/Mg(OH)2/GO.
Structural basis for C4 photosynthesis without Kranz anatomy in leaves of the submerged freshwater plant Ottelia alismoides
Authors: Han Shijuan , Maberly Stephen C , Gontero Brigitte , Xing Zhenfei , Li Wei , Jiang Hongsheng , Huang Wenmin 
Published: January 2020

Abstract

Background and Aims
Ottelia alismoides (Hydrocharitaceae) is a freshwater macrophyte that, unusually, possesses three different CO2-concentrating mechanisms. Here we describe its leaf anatomy and chloroplast ultrastructure, how these are altered by CO2 concentration and how they may underlie C4 photosynthesis.

Methods
Light and transmission electron microscopy were used to study the anatomy of mature leaves of O. alismoides grown at high and low CO2 concentrations. Diel acid change and the activity of phosphoenolpyruvate carboxylase were measured to confirm that CAM activity and C4 photosynthesis were present.

Key Results
When O. alismoides was grown at low CO2, the leaves performed both C4 and CAM photosynthesis whereas at high CO2 leaves used C4 photosynthesis. The leaf comprised an upper and lower layer of epidermal cells separated by a large air space occupying about 22 % of the leaf transverse-section area, and by mesophyll cells connecting the two epidermal layers. Kranz anatomy was absent. At low CO2, chloroplasts in the mesophyll cells were filled with starch even at the start of the photoperiod, while epidermal chloroplasts contained small starch grains. The number of chloroplasts in the epidermis was greater than in the mesophyll cells. At high CO2, the structure was unchanged but the thicknesses of the two epidermal layers, the air space, mesophyll and the transverse-section area of cells and air space were greater.

Conclusions
Leaves of O. alismoides have epidermal and mesophyll cells that contain chloroplasts and large air spaces but lack Kranz anatomy. The high starch content of mesophyll cells suggests they may benefit from an internal source of CO2, for example via C4 metabolism, and are also sites of starch storage. The air spaces may help in the recycling of decarboxylated or respired CO2. The structural similarity of leaves at low and high CO2 is consistent with the constitutive nature of bicarbonate and C4 photosynthesis. There is sufficient structural diversity within the leaf of O. alismoides to support dual-cell C4 photosynthesis even though Kranz anatomy is absent.
Strong sexual selection despite spatial constraints on extrapair paternity
Authors: Cramer Emily R A , Greig Emma I , Kaiser Sara A 
Published: January 2020

Abstract
Extrapair paternity should contribute to sexual selection by increasing the number of potential mates available to each individual. Potential copulation partners are, however, limited by their proximity. Spatial constraints may therefore reduce the impact of extrapair paternity on sexual selection. We tested the effect of spatial constraints on sexual selection by simulating extrapair copulations for 15 species of socially monogamous songbirds with varying rates of extrapair paternity. We compared four metrics of sexual selection between simulated populations without spatial constraints and populations where extrapair copulations were restricted to first- and second-order neighbors. Counter to predictions, sexual selection as measured by the Bateman gradient (the association between the number of copulation partners and offspring produced) increased under spatial constraints. In these conditions, repeated extrapair copulations between the same individuals led to more offspring per copulation partner. In contrast, spatial constraints did somewhat reduce sexual selection—as measured by the opportunity for selection, s’max, and the selection gradient on male quality—when the association between simulated male quality scores and copulation success (e.g., female preferences or male–male competition) was strong. Sexual selection remained strong overall in those populations even under spatial constraints. Spatial constraints did not substantially reduce sexual selection when the association between male quality and copulation success was moderate or weak. Thus, spatial constraints on extrapair copulations are insufficient to explain the absence of strong selection on male traits in many species.