Rapid Polishing Research Articles

Process Design and Assessment of the Performance of Three Macrophytes in a Biorefinery Polishing Partly Treated Sewage in Novel SHEFROL Bioreactors

The development of a biorefinery is described based on rapid polishing of partially treated sewage with three different species of macrophytes in the recently developed SHEFROL® bioreactor which functions almost entirely on solar and gravitational energy, requiring no chemicals. It was seen that at a hydraulic retention time (HRT) of just 2 h, suspended solids, COD, BOD, total Kjeldahl nitrogen, soluble phosphorus, zinc, copper, nickel, and manganese are reduced to the extents of 92–95%, 76–78%, 77–81%, 56–61%, 60–66%, 43–46%, 45–48%, 30–35%, and 31–33%, respectively. The treated water meets the water quality standards set for the discharge into surface water bodies. M. quadrifolia was seen to be most effective of the three macrophytes, followed by P. stratiotes and S. molesta, as a sewage cleansing agent, but the difference in the performance of the macrophytes was only marginal, and not highly significant statistically (p ≥ 0.5). The paper also shows that it is possible to extract energy precursors in the form of volatile fatty acids (VFAs) from the harvested macrophyte biomass and then convert the biomass into organic fertiliser. All the steps associated with the closed loop circular biorefinery occur at ambient temperatures and pressures, requiring little consumption of energy and materials, and leaving negligible footprints.

Rapid polishing process for the x ray reflector.

X ray mirrors are symmetrical workpieces along the length and width and are widely used in various optical systems. Unlike the center-symmetric circular mirror, it is more difficult to suppress the edge effect of the x ray mirror during the polishing process, which greatly limits the polishing accuracy and polishing efficiency. Based on this, the unique edge effect of x ray mirrors is investigated in depth in this paper. First, the causes and distribution laws of the edge effect of the x ray mirror were obtained by analyzing the inherent structure of the computer controlled optical surface (CCOS) and the motion trajectory of the polishing tool. Second, a mathematical model was established based on the material removal states of different regions on the x ray mirror. Finally, a combined polishing process based on the influence function of different shaped tools is proposed and experimentally verified. The results show that the edge effect on the x ray mirror is significantly weakened and its surface errors peak to valley (PV) and RMS are increased by 21.5 times and 47.9 times, respectively. This indicates that the combined polishing process has a good suppression effect on the edge effect of the x ray mirror.

Optimization of static performance for robot polishing system based on work stiffness evaluation

Robot-assisted bonnet polishing system (RABPS) is widely used in the polishing of optical components due to its low cost, high efficiency and rapid polishing. However, due to the insufficient stiffness of the robot, it is easy to produce vibration in the machining process, which not only causes the size of the polishing contact area to deviate from the ideal value, but also affects the removal amount of workpiece. First, this paper analyzes the influence of robot system stiffness on the actual polishing area size and polishing removal. Next, based on the analysis of the technical characteristics of multiple groups of polishing posture corresponding to the same point of robot bonnet polishing, the optimization method of robot static stiffness performance is proposed. Finally, the correctness and efficiency of the optimization method are validated by simulation and experiment. The working stiffness of the robot increases by 26.8% and the roughness of the polished surface is improved by 42.9% after posture optimization.

Influence of robotic structural deformation on bonnet polishing removal function

Precision polishing system for opticals based on bonnet polishing technology and industrial robot can not only meet the requirements of high efficiency and precision of rapid polishing, but also reduce the development cost, thus it is a potential development solution for polishing. Bonnet polishing requires stable and deterministic material removal characteristics, and the stability of polishing spot is usually around 90%. The influence of robot stiffness on the stability of robot bonnet polishing system in the process of multi-step discrete precession polishing was studied. The robot end deformation was analyzed by the stiffness matrix, and the removal function of bonnet polishing with deformation error was established based on Preston theory. Finally, a four-step discrete polishing experiment was designed. According to the results, the polishing spot was Gaussian on the xy section contour line, and the xy section contour line was basically the same, with a good coincidence degree. Comparison of the cross-section profiles at different polishing positions indicates, the relative errors are below 5%. The experiment proves that the robot bonnet polishing system has a good stability in discrete precast polishing.

Evaluation of Skid Resistance of Wearing Course Made Of Stone Mastic Asphalt Mixture in Laboratory Conditions

This paper presents the comparison of skid resistance of wearing course made of SMA (Stone Mastic Asphalt) mixtures which differ in resistance to polishing of coarse aggregate. Dolomite, limestone, granite and trachybasalt were taken for investigation. SMA mixtures have the same nominal size of aggregate (11 mm) and very similar aggregate particle-size distribution in mineral mixtures. Tested SMA11 mixtures were designed according to EN 13108-5 and Polish National Specification WT-2: 2014. Evaluation of the skid resistance has been performed using the FAP (Friction After Polishing) test equipment also known as the Wehner/Schulze machine. Laboratory method enables to compare the skid resistance of different types of mixtures under specified conditions simulating polishing processes. Tests were performed on both the specimens made of each coarse aggregate and SMA11 mixtures containing these aggregates. Measuring of friction coefficient μm was conducted before and during polishing process up to 180 0000 passes of polishing head. Comparison of the results showed differences in sensitivity to polishing among particular mixtures which depend on the petrographic properties of rock used to produce aggregate. Limestone and dolomite tend to have a fairly uniform texture with low hardness which makes these rock types susceptible to rapid polishing. This caused lower coefficient of friction for SMA11 mixtures with limestone and dolomite in comparison with other test mixtures. These significant differences were already registered at the beginning of the polishing process. Limestone aggregate had lower value of μm before starting the process than trachybasalt and granite aggregate after its completion. Despite the differences in structure and mineralogical composition between the granite and trachybasalt, slightly different values of the friction coefficient at the end of polishing were obtained. Images of the surface were taken with the optical microscope for better understanding of the phenomena occurring on the surface of specimen. Results may be valuable information when selecting aggregate to asphalt mixtures at the stage of its design and maintenance of existing road pavements.

Research on Mid-Large-Aperture Aspherical Optical Components Rapid Powerful NC Polishing Technology

This paper introduces a new devices and technology of large-aperture quadratic optical components rapid powerful NC polishing, it has greatly improved the efficiency and precision of aspheric polishing. Through self-designed five-axis CNC polishing machine, to achieve the controlling of rotation, revolution integral rapid powerful polishing head. By optimizing the process parameters, determine a reasonable polishing path and polishing mode structure, to obtain good experimental results. Size 340mm × 340mm aspheric optical glass, surface shape accuracy PV λ / 5, surface roughness Rq 1.2nm, processing efficiency has been effectively improved, surface shape convergence stable.

先进光学制造技术进展

The paper summarizes the recent progress of advanced manufacturing technology for the high power laser system in China. The ultra-precision manufacturing technologies, such as ultra-precision grinding, single point diamond fly-cutting and rapid polishing, have been developed for aspheric lens and KDP crystal flats. The preliminary results show the advantages in achieving high accuracy and the ability of yield. Several deterministic finishing technologies have been studied to meet the critical wavefront specifications. A novel removing-mitigating process has been applied to polishing fused silica components to reduce the subsurface defects.

Study on Technological Parameters of Polishing Large Aspheric Elements

Large aspheric elements in giant laser facility are fabricated using computer controlled rapid polishing technology. The technological parameters are main influencing factors of efficiency. Base on Preston hypothesis, linear relationship of material removal with polishing pressure, polishing velocity and other conditions are established. According to the material removal function model of computer controlled rapid polishing, the removal function is simulated using MATLAB software. The influencing factors of volume removal efficiency are analyzed. In practice, the optimum polishing parameters are eccentricity 0.4, rotational velocity of principal axis 330 rpm, rotational velocity of polishing pad -600 rpm.

Development of a Rapid Polishing Machine for On-Site Optical Connector Assemble

Field assembly of optical connectors is demanded because of the wide use of optical fiber in telecommunications systems. We propose a new assembling techniques that enable us to assemble connectors anywhere quickly and cost effectively. The key points are an adhesive technique and a polishing technique. In this report, we focus mainly on our a new polishing machine, which is suitable for optical connector ends machining on-site. The machine which is small and light weight can finish optical connector ends easily in a short time with enough low cost.

Development of Rapid Polishing Method for Brewer's Rice and Evaluation of Polished Rice Properties.

Using a small-type rice miller, Pearlest, equipped with barley polishing parts, brown rice could be simply and rapidly polished up to the targeted polishing ratio of 70 %. This method was characterized by a low ratio of broken rice, reduction of the loss of moisture content of the samples, and more spherical polishing of rice kernels. Twenty-minute water absorption was clearly enhanced in varieties such as Ipponjime with kernels showing a low hardness, and the nitrogen content was lower compared with the control method. But these tendencies were not considered to hinder the evaluation of relative varietal differences, because it was found that the nitrogen content and 20-minute water absorption ratio of polished rice by this method could be utilized as stable evaluation parameters revealing the intrinsic characteristics of the varieties. Development of this rapid polishing method is considered to be extremely important for efficient selection in breeding programs for brewer’s rice, because it may be possible to evaluate the nitrogen content of 70 %-polished rice and water absorption properties which had not been examined so far in earlier generations.

An Updated Ion Polishing System for Tem Specimen Preparation of Materials

AbstractThe construction and performance of an improved ion milling instrument are described. The updated instrument is based upon an earlier version fixed low angle ion milling system. The updated system employs two improved guns having the ability of independent variable milling angle adjustment, while operating at high voltage in the vacuum system. The milling rate of these ion guns is typically ≈ 90μm/hr/gun pair for copper at 5keV and 10°. Designed to compliment the variable angle ion gun is a new specimen holder which permits low angle double sided milling. The combination of these two features offers numerous single or double sided milling conditions to facilitate the production of higher quality TEM specimens in less time. The range of ion gun angles encompassed is 0° to 10° for single-sided milling and 0° to ± 10° for double-sided milling. The instrument also incorporates an electronic mechanism to generate directional sector milling which benefits primarily the production of cross sectional TEM specimens and heat sensitive materials since the ion guns are turned off for a portion of time during each revolution. Another new feature of the instrument is chemical ion milling which facilitates the preparation of certain compound semiconductors. The ability of this improved ion milling instrument for rapid ion polishing and improved specimen quality is demonstrated by a number of TEM images of metals, ceramics and semiconductors.

Age Determination of Mountain Hares (Lepus timidus): A Rapid Method and When to Use It

(1) The method described enables rapid polishing of sections of bone tissue to permit age determination from annual growth lines. (2) A sample of mandibles from twenty mountain hares of known age from N.E. Scotland provided a calibration for the method. (3) The growth lines probably form during the autumn, in October and November, and hence the method is less accurate if applied then. This loss of accuracy applies generally to age determinations using growth lines and has often been overlooked. (4) In the population of mountain hare females studied in 1984, there was a scarcity of females born in 1980.

A method for the rapid mounting and polishing of ceramic materials for microstructural examinations

A method for the rapid mounting and polishing of ceramic materials for microstructural examinations