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RILL EROSION PROCESS AND RILL FLOW HYDRAULIC PARAMETERS
In the rill erosion process,run-on water and sediment from upslope areas,and rill flow hydraulic parameters have significant effects on sediment detachment and transport.However,there is a lack of data to quantify the effects of run-on water and sediment and rill flow hydraulic parameters on rill erosion process at steep hillslopes,especially in the Loess Plateau of China.A dual-box system,consisting of a 2-m-long feeder box and a 5-m-long test box with 26.8% slope gradient was used to quantify the effects of upslope runoff and sediment,and of rill flow hydraulic parameters on the rill erosion process.The results showed that detachment-transport was dominated in rill erosion processes; upslope runoff always caused the net rill detachment at the downslope rill flow channel,and the net rill detachment caused by upslope runoff increased with a decrease of runoff sediment concentration from the feeder box or an increase of rainfall intensity.Upslope runoff discharging into the rill flow channel or an increase of rainfall intensity caused the rill flow to shift from a stratum flow into a turbulent flow.Upslope runoff had an important effect on rill flow hydraulic parameters,such as rill flow velocity,hydraulic radius,Reynolds number,Froude number and the Darcy-Weisbach resistance coefficient.The net rill detachment caused by upslope runoff increased as the relative increments of rill flow velocity,Reynolds number and Froude number caused by upslope runoff increased.In contrast,the net rill detachment decreased with an increase of the relative decrement of the Darcy-Weisbach resistance coefficient caused by upslope runoff.These findings will help to improve the understanding of the effects of run-on water and sediment on the erosion process and to find control strategies to minimize the impact of run-on water....
2020-11-10 09:33:08浏览：77
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Microscale and Nanoscale Process Systems Engineering: Challenge and Progress
This is an overview of the development of process systems engineering (PSE) in a smaller world. Two different spatio-temporal scopes are identified for microscale and nanoscale process systems. The features and challenges for each scale are reviewed, and different methodologies used by them discussed. Comparison of these two new areas with traditional process systems engineering is described. If microscale PSE could be considered as an extension of traditional PSE, nanoscale PSE should be accepted as a new discipline which has looser connection with the extant core of chemical engineering. Since "molecular factories" is the next frontier of processing scale, nanoscale PSE will be the new theory to handle the design, simulation and operation of those active processing systems....
2020-11-10 09:33:08浏览：49
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Preparation of Biologically Active Materials by Biomimetic Process
In order to form the apatite nuclei on a surface of the substrate,the substrate was placed on or in CaO,SiO2-based glass particles which were soaked in a simulated body fluid with ion concentrations nearly equal to those of human blood plasma,and to make the apatite nuclei grow on the substrate in situ,the substrate was soaked in another solution highly supersaturated with respect to the apatite. The induction period for the apatite nucleation varied from 0 to 4 days depending on the kind of the substrate. The thickness of the apatite layer increases linearly with increasing soaking time in the second solution.The rate of growth of the apatite layer increases with increasing degree of the supersaturation and temperature of the second solution, reaching 7um/d in a solution with ion concentrations which is as 1.5 times as those of the simulated body fluid at 60 ℃. The adhesive strength of the apatite layer to the substrate varies depending on the kind and roughness of the substrate. Polyethyleneterephthalate and polyethersulfone plates abraded with No.400 diamond paste show adhesive strengths of as high as 4 MPa. This type of composite of the bone-like apatite with metals, ceramics and organic polymers might be useful not only as highly bioactive hard tissue-repairing materials with analogous mechanical properties to those of the hard tissues, but also as highly biocompatible soft tissue-repairing materials with ductility....
2020-11-10 09:33:08浏览：44
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An exemplification of the Evolving Process by Studying the Chinese Character Mao
This paper tries to demarcate the evolving process of decategorization into three periods and exemplify it by studying the Chinese character Mao. The exemplification shows the correctness of the demarcation....
2020-11-10 09:33:08浏览：44
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Impact of hydrothermal process on the nutrient ingredients of restaurant garbage
In order to recover the nutrient resource from restaurant garbage, a complete trial with 2 factors on 5 levels of experiments was carried out. The temperature and heating time are the main factors influencing on hydrotherrnal process (HP) by which improves the degradability and digestibility of the restaurant garbage favorably to make animal feeds or fertilizer. The results showed the variation of protein, saccharide, and oil in the garbage. It showed that protein dissolved and liquefied during hydrothermal process,which made organic nitrogen in solid phase transfer to liquid phase. After heating at 180℃ for 60 min, organic nitrogen in liquid phase began to transform into ammonia. It also showed that hydrothermal process could promote the dextrinization, dissolution of the starch and its hydrolysis to reducing sugar, due to that starch in the restaurant garbage decreases and reducing sugar increases. When the temperature reached 140℃, the reducing sugar started to decrease due to chemical reactions. The cellulose was stable at 100- 180℃.The floatable oil increased markedly in the hydrothermal process. The suitable condition for de-oil was observed at 160℃ heating for 80 min. Furthermore, the extraction of grease from the solid phase accords with first-order reaction dynamic model....
2020-11-10 09:33:08浏览：62
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Research on Fuzzy Synthetic Evaluation of Stamping Process Scheme
Stamping process, which is widely used in automobile, aerospace, machine-building industries, and etc., is a creative process needing time and experiences. The lead time is mainly spent on stamping die design and manufacturing. As the basis of die design, process design is a non-linearity and creative process, which can be solved by using the fuzzy synthetic evaluation. In this paper, the potential of fuzzy synthetic evaluation for dealing with stamping process design was explored. The influencing factor set, factor weight set, evaluation set, single factor fuzzy evaluation matrix, and fuzzy synthetic evaluation scheme were studied. Finally, the washer part, considering forming equipment, part dimensions and other factors, was selected to testify the evaluation process....
2020-11-10 09:33:08浏览：47
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PROCESS CAPABILITY ANALYSIS AND ESTIMATION SCHEME FOR AUTOCORRELATED DATA
Autocorrelation is prevalent in continuous production processes,such as the processes in the chemical and pharmaceutical industries.With the development of measurement technology and data acquisition technology,sampling frequency is getting higher and the existence of autocorrelation cannot be ignored.This paper analyzes five estimation schemes of process capability for autocorrelated data.Comparisons among these schemes are discussed for small sample and large sample.In conclusion,this paper gives a procedure of process capability analysis for autocorrelated data....
2020-11-10 09:33:08浏览：67
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Preparation of montmorillonite modified phenolic resin for shell process
The development of montmodllonite modified phenolic resin under microwave irradiation heating was investigated. The effect of montmorillonite content and stirring time on the structure and morphology of synthetic resin was analyzed. The optimum processing procedure was found to be 45 rain stirring time with 5.4% montmorillonite addition. Further, the platelet spacing increases with stirring time till montmorillonite exfoliated to nanoscales platelet. When montmorillonite is exfoliated, layered structure at nanoscale can be uniformly distributed in the resin. The overall performance of montmorillonite modified phenolic resin is improved remarkably, such as flow ability, tensile strength and toughness property of resin coated sand. However, the gelation speed decreased slightly by adding montmorillonite....
2020-11-10 09:33:08浏览：52
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Application of Microstructure Engineering in Steel Coil Cooling Process
The coil cooling and its role in a hot strip mill were reviewed.A mathematical model was developed to describe and analyze the thermal history and its impact on precipitation phenomena during coil cooling for plain car bon,HSLA-V and HSLA-Nb steels.The predicted result of the thermal model was compared with that measured from industrial coil.The effect of cooling condition and coil dimension on the thermal history and final mechanical properties of the steel strip was examined.The coiling temperature and cooling rate have crucial influence on the precipitation strengthening....
2020-11-10 09:33:08浏览：67
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Induced Discoloration of Buerger Maple during Drying Process
Buerger maple (Liquidambar formosana Hance) is a kind of wood that is easily discolored. This paper tries to obtain satisfactory color and a broad prospect in the utilization of buerger maple by induced discoloration. The authors analyze the mechanism of induced discoloration of buerger maple based on the analysis of visual physical parameter, the infrared spectrum (IRS) and the scanning electron microscope (SEM) under different drying conditions. The result shows that it is feasible to induce discoloration during the drying process. The wood color tends to be red and fuscous during inducing discoloration of buerger maple. The induced discoloration mechanism is: 1) the high temperature and humidity accelerates the oxidation reaction of polyphenol, leuco-fancy pigment and tannin, which changes the wood color to red; 2) the hydroxy (―OH) is oxidized and the carbonyl (―C═O), carboxyl (―COOH), ester and ketone groups form during the high temperature steaming, which results in wood piece discoloration....
2020-11-10 09:33:08浏览：62
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The dynamic power management for embedded system with Poisson process
The mass of the embedded systems are driven by second batteries, not by wired power supply. So saving energy is one of the main design goals for embedded system. In this paper we present a new technique for modelling and solving the dynamic power management (DPM) problem for embedded systems with complex behavioural characteristics. First we model a power-managed embedded computing system as a controllable Flow Chart. Then we use the Poisson process for optimisation, and give the power management algorithm by the help of Dynamic Voltage Scaling (DVS) technology. At last we built the experimental model using the PXA 255 Processors. The experimental results showed that the proposed technique can achieve more than12％ power saving compared to other existing DPM techniques....
2020-11-10 09:33:08浏览：52
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Perturbation Solutions for Thermal Process of Honeycomb Regenerator
A parameter perturbation for the unsteady-state heat-transfer characteristics of honeycomb regenerator is presented. It is limited to the cases where the storage matrix has a small wall thickness so that no temperature variation in the matrix perpendicular to the flow direction is considered. Starting from a two-phase transient thermal model for the gas and storage matrix, an approximate solution for regenerator heat transfer process is derived using the multiple-scale method for the limiting case where the longitudinal heat conduction of solid matrix is far less than the convective heat transfer between the gas and the solid. The regenerator temperature profiles are expressed as Taylor series of the coefficient of solid heat conduction item in the model. The analytical validity is shown by comparing the perturbation solution with the experiment and the numerical solution. The results show that it is possible for the perturbation to improve the effectiveness and economics of thermal research on regenerators....
2020-11-10 09:33:08浏览：51
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Cellular modelling using P systems and process algebra
In this paper various molecular chemical interactions are modelled under different computational paradigms. P systems and π-calculus are used to describe intra-cellular reactions like protein-protein interactions and gene regulation control....
2020-11-10 09:33:08浏览：62
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Research of Degumming Process, Microstructure and Properties of Mulberry Fiber
More and more novel nature fibers are used in textiles. The natural fibers include banana fiber, pineapple fiber and bamboo fiber etc. In this paper, as a kind of novel natural fiber, mulberry fiber is studied. The chemical component of mulberry bast is tested and analyzed.Meanwhile, the degumming method and process of mulberry bast are studied. Chemical degumming experiments to investigate the influence of alkali concentration, alkali boiling time and sodium phosphate tribasic ratio to material are conducted. Consequently, optimum parameters are obtained. The crystallinity of mulberry fiber is tested by using X-ray line, and the photos of scanning electron microscope (SEM) are observed. Testing results of the fiber properties (e. g. fineness, tenacity, length and elongation)show that mulberry fiber can be spun blend with cotton....
2020-11-10 09:33:08浏览：57
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An Analysis of Metaphor Comprehension Process from Psycholinguistic Perspective
This paper aims to present some issues about metaphor comprehension process mainly from psycholinguistic point of view.By dis-cussing these issues,more information about the nature of metaphor comprehension can be learnt....
2020-11-10 09:33:08浏览：58
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