刚性极与粗平抛石基床间随机相互作用的数学模型

本文建立了刚性板下粗平抛石基床压缩量叠加公式,修正了文献模型,并通过实验验证了本文数学模型。

多彩粗平花呢的设计与生产

本文就流行色在粗平花呢设计的技巧上进行了阐述。

粗针平刺身柱穴治疗肌张力增高验案举隅

粗针源于《黄帝内经》中的“九针”，是“九针”中长针与大针的结合体。针身粗、长，长为120mm，直径为1．0mm。取穴基本在督脉，身柱为督脉穴，为督脉之脉气所发，位于上背部正中，第三胸椎棘突下。名为身柱，含有全身支柱之意，为督脉出入之门户。《针灸甲乙经》：“……瘛疚，身柱主之。”粗针平刺身柱穴，通过长时间留针，使患者获得长时间的针刺作用，可平衡阴阳、调和脏腑、濡养经筋。笔者近年来采用该法治疗脑、脊髓病变引起的肢体肌张力增高，疗效满意。现举医案介绍于下。

平菇蛋白粗提液诱导烟草对TMV的抗性与细胞中防御酶活性的关系

用200μg/mL的平菇蛋白粗提液处理枯斑三生烟后接种烟草花叶病毒(Tobacco mosaic virus,TMV),在不同时间测定了烟草植株叶片中苯丙氨酸解氨酶(phenylalanine ammonialyas,PAL)、超氧化物歧化酶(superoxidedismutase,SOD)、过氧化氢酶(catalase,CAT)和过氧化物酶(peroxidase,POD)的活性。结果表明,平菇蛋白粗提液处理枯斑三生烟后,TMV的侵染率下降了70.16%;接种TMV后,平菇蛋白粗提液处理的烟草叶片中的PAL、SOD、CAT和POD活性要明显高于清水对照植株,接种后12 h PAL活性最高,平菇蛋白粗提液处理为清水对照的1.57倍;接种后24 h SOD和POD活性最高,平菇蛋白粗提液处理分别为清水对照的1.55倍和1.51倍;接种后36 h CAT活性最高,平菇蛋白粗提液处理为清水对照的1.6倍。以上研究结果表明,平菇蛋白粗提液诱导烟草抗TMV的活性与烟草叶片内防御酶活性的提高有关。

重力式码头基床整平施工技术

本文介绍福建福清核电厂一期工程大件码头工程基床整平特点。主要是对重力式码头水下基床整平施工工艺进行论述。

Nanogrinding of SiC wafers with high flatness and low subsurface damage

Nanogrinding of SiC wafers with high flatness and low subsurface damage was proposed and nanogrinding experiments were carried out on an ultra precision grinding machine with fine diamond wheels. Experimental results show that nanogrinding can produce flatness less than 1.0μm and a surface roughness Ra of 0.42nm. It is found that nanogrinding is capable of producing much flatter SiC wafers with a lower damage than double side lapping and mechanical polishing in much less time and it can replace double side lapping and mechanical polishing and reduce the removal amount of chemical mechanical polishing.

水准仪与经纬仪操作经验之谈

水准仪最基本的功能是测定两点之间的高差,用于高程传递测量;经纬仪的主要功能是用来测量角度的,包括水平角和竖直角,最常用的是水平角的测量。但在具体测量过程中,容易混淆两种仪器的操作。本文针对实践教学过程中学生容易出现的问题,阐述两种仪器在具体操作过程中的容易混淆之处,便于熟练掌握仪器的操作。

平菇菌丝发酵液粗多糖对多种肠道益生菌的影响

目的探究平菇菌丝发酵液粗多糖对多种肠道益生菌生长的影响。方法采用发酵工程技术获得平菇菌丝发酵液并提取平菇菌丝分泌的粗多糖。将平菇菌丝发酵液粗多糖分别以浓度10.0%、5.0%、2.5%以及0%的空白对照对青春双歧杆菌、干酪乳杆菌、乳杆菌MZ900、嗜酸乳杆菌生长的影响进行观察。结果在含平菇菌丝粗多糖10.0%以下的菌液范围内随着平菇菌丝发酵液粗多糖含量的增加,4种肠道益生菌的生长成正相关增长。结论平菇菌丝发酵液粗多糖对4种肠道益生菌有增菌效果。研究结果为平菇菌丝发酵液粗多糖有保护人类肠道功能的作用提供理论依据,以及为后续研究提供建议。

Recovery of indium and lead from lead bullion

Lead and indium were recovered by electrolysis and nonequilibrium solvent extraction process from lead bullion. The effects of current density, electrolytic period and circle arpJ ant of electrolyte on the electrochemical dissolution of lead and indium were investigated. The effects of extraction phase ratio and mixing time on solvent extraction of indium and striping phase ratio and stripping stage on the loaded organic phase stripping were also investigated. The experimental results indicate that under optimum conditions, the purity of lead deposited on cathode is 98.5% and the deposit rate of lead is 99.9%, the dissolution rate of indium is 94.28%, the extraction rate of indium is 98.69%, the stripping rate of indium is almost 100%, and the impurity elements, such as Zn, Fe and Sn can be removed.

Attribute reduction based on background knowledge and its application in classification of astronomical spectra data

To improve the efficiency of the attribute reduction, we present an attribute reduction algorithm based on background knowledge and information entropy by making use of background knowledge from research fields. Under the condition of known background knowledge, the algorithm can not only greatly improve the efficiency of attribute reduction, but also avoid the defection of information entropy partial to attribute with much value. The experimental result verifies that the algorithm is effective. In the end, the algorithm produces better results when applied in the classification of the star spectra data.

Effect of electromagnetic and ultrasonic cast rolling on microstructure and properties of 1050 aluminum substrate for presensitized plate

The 1050 aluminum alloy strip was prepared by means of electromagnetic and ultrasonic cast rolling on the modified asymmetric twin roll caster, and then the aluminum substrate for presensitized plate was prepared through cold rolling and annealing.The effects of electromagnetic and ultrasonic cast rolling on microstructure, mechanical properties, surface roughness and electrolytic corrosion properties of 1050 aluminum substrate were studied. The results show that electromagnetic and ultrasonic cast rolling can decrease the average crystallite size of aluminum substrate by 5 μm, increase the crystal boundaries with uniform distribution, and make the second-phase particles with smaller size distributed dispersively in the substrate, meanwhile, it can increase the tensile strength, elongation and micro-hardness by 4.58%, 9.85% and HV 2, respectively, reduce the surface roughness, make the surface appearance more even, electrolytic corrosion polarization curve of aluminum substrate more smooth and the surface corrosion pits with regular shape more dispersive.

Effect of Feeding Different Levels of Dietary Protein and Addition of Baker＇s Yeast （Saccharomyces cerevisiae） on Productive Parameters of Awassi Lambs

Forty eight individually fed Awassi male lambs were used in factorial experiment to investigate their responses to feeding concentrate diets containing three levels of dietary crude protein （CP）, each was offered without or with baker＇s yeast （SC） at rate of 0.5% （on dry matter （DM） basis）. Concentrates were offered at rate of 3% of live body weight with free choice of barley straw. Results revealed that higher （P 〈 0.05） digestible dry matter （DDM） and digestible organic matter （DOM） intakes were achieved due to feeding medium level of CP and to the addition of SC. Addition of SC improved （P 〈 0.05） gain, lambs fed medium and high levels gained higher （P 〈 0.05） than those fed the low level of dietary CP. Feed conversion ratio （FCR） based on DM and organic matter （OM） intakes was not significantly affected by level of dietary CP or addition of yeast. Even though, less amount of N required per unit of gain was achieved with low and medium as compared to high levels. Higher DM, nitrogen free extract （NFE） and hemicellulose （P 〈 0.05）, OM, CP, crude fiber （CF） and cellulose （P 〈 0.01） digestibilities were achieved in lambs fed the medium level of CP, whereas, no significant effect was observed on ether extract （EE）, neutral detergent fiber （NDF） and acid detergent fiber （ADF） digestibilities. Results also revealed that digestibility of almost all nutrients was improved with different extent due to addition of SC. Effect of interaction between levels of dietary CP and addition of SC referred to the preferability of addition of SC with medium level of dietary protein.

Sea Surface Effects on Sound Scattering in the Persian Gulf Region Based on Empirical Relations

In this paper, sound scattering from the sea surface in the Persian Gulf region is investigated. Chapman-Harris and Ogden-Erskine empirical relations coupled with perturbation theory are implemented. Based on the Ogden and Erskine＇s experiments, sound scattering from the sea surface has three different regimes in which two mechanisms of surface roughness and subsurface bubble clouds are involved. Ogden-Erskine＇s scattering relation which consists of perturbation theory and Chapman-Harris＇s scattering terms are verified by the experimental data of Critical Sea Tests 7. Subsequently, wind speed in the Persian Gulf is provided based on three data bases of Arzanah station, ERA40, and PERGOS. Accordingly, surface scattering strength in the Persian Gulf region is calculated at different grazing angles, frequencies and provided wind speeds. Based on the resulted values of scattering strength, scattered intensity from the sea surface is also studied. These studies indicate that both scattering strength and scattered intensity generally increase as grazing angle, frequency and wind speed increase.

Where do Random Rough Surfaces Fail？ Part I： Fracture Loci Safety Envelopes at Early Stages of Degradation

Damage on surfaces often compromises the efficiency of some types of energy production, the safety and reliability of components, and ultimately increases costs. The environment can degrade the structural integrity of surfaces in service by the accumulation of large numbers of small destructive events, which based on the Central Limit Theorem leads to a Gaussian distribution of pit depth. In order to develop safety envelopes relating fracture loci with topological parameters of a brittle material, scatter plots were obtained and analyzed. Starting with an engineering surface, after 6 to 9 micrometers of average degradation depth, safety envelopes could be developed using average roughness and two other proposed parameters. Interestingly, maximum pit depth showed very low correlation with the location of fracture, at the early stage of degradation studied. This is attributed to relaxation of stress concentration at a given pit location due to the assuaging effect caused by neighboring pits. Additionally, energy at fracture was obtained, and a maximum relaxation region was observed. Analytical and experimental study of this region, as well as ductility effects are currently under research.

Applying rough sets in word segmentation disambiguation based on maximum entropy model

To solve the complicated feature extraction and long distance dependency problem in Word Segmentation Disambiguation （WSD）, this paper proposes to apply rough sets ill WSD based on the Maximum Entropy model. Firstly, rough set theory is applied to extract the complicated features and long distance features, even frnm noise or inconsistent corpus. Secondly, these features are added into the Maximum Entropy model, and consequently, the feature weights can be assigned according to the performance of the whole disambiguation mnltel. Finally, tile semantic lexicou is adopted to build class-hased rough set teatures to overcome data spareness. The experiment indicated that our method performed better than previous models, which got top rank in WSD in 863 Evaluation in 2003. This system ranked first and second respcetively in MSR and PKU open test in the Second International Chinese Word Segmentation Bankeoff held in 2005.

A Study on Modelling Surface Finish in Electrical Discharge Machining Tablet Shape Punches Using Response Surface Methodology

This paper introduces a study on modelling surface finish in EDM （Electrical Discharge Machining） of tablet shape punches when using copper as electrode material. In this study, 27 experiments were performed based on BBD （Box-Behnken Design） and the work-piece material was 9CrSi steel. The input process parameters were the current, the pulse on time, the pulse off time and the voltage. The effects of the input parameters on the surface finish were evaluated by analysing variance. Besides, from the results of the experiments, a regression equation for determining the surface roughness is introduced. Also, the optimum input parameter values were found in order to get the minimum surface roughness.

Optimum design of carbon/carbon ablative property based on genetic algorithm

An optimum design model has been proposed for carbon/carbon ablative property based on genetic algorithm,in which the optimum parameters are the number of woven satins,K of fiber bundles,layers per unit height,the average distance of puncture fibers in Z direction and Ply Stacking angle,and the constraint conditions are the density and diameter of carbon fibers and the density of carbon matrix.The results demonstrate that after optimization,the overall height of the ablative carbon/carbon surface is reduced by 56.5%,the standard deviation is reduced by 34.9% and the surface roughness is reduced by 12.6%,which suggests the remarkable improvement of ablative homogeneity.The present investigation can provide practical methodology for the optimum design of carbon/carbon ablative property and the development of new carbon/carbon composites.

Tool sharpness in precision micro cutting process

As to probe the factors affecting the roughness and surface properties of work piece in mirco-cutting machining process, according to the principle of energy balance, using the method of experiments combining with theoretical analysis, this paper investigates the effect of cutting edge radius on the unit cutting force, the cutting component forces ratio Fy/Fz, as well as the roughness and surface properties of the work-piece. Experimental results show that the value of tool cutting edge arc ρ has a significant impact on elastic-plastic deformation of the cutting area, and its influence on the surface quality of processing and precision is greater than common cutting. The method of calculating the theoretical limits of the diamond tool cutting edge radius is feasible. The value of 0.0001 μm has some guiding significance for the developement of suitable cutting thickness to ensure the normal cutting.

Implementation of a Roughness Element to Trip Transition in Large-eddy Simulation

In aerodynamics, the laminar or turbulent regime of a boundary layer has a strong influence on friction or heat transfer. In practical applications, it is sometimes necessary to trip the transition to turbulent, and a common way is by use of a roughness element （e.g. a step） on the wall. The present paper is concerned with the numerical im- plementation of such a trip in large-eddy simulations. The study is carried out on a flat-plate boundary layer con- figuration, with Reynolds number Rex=l.3x 106. First, this work brings the opportunity to introduce a practical methodology to assess convergence in large-eddy simulations. Second, concerning the trip implementation, a volume source term is proposed and is shown to yield a smoother and faster transition than a grid step. Moreover, it is easier to implement and more adaptable. Finally, two subgrid-scale models are tested： the WALE model of Nic0ud and Ducros （Flow Turbul. Combust., vol. 62, 1999） and the shear-improved Smagorinsky model of Ldv^que et al. （J. Fluid Mech., vol. 570, 2007）. Both models allow transition, but the former appears to yield a faster transition and a better prediction of friction in the turbulent regime.