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1.
Preface:Nowadays, standardization is playing a more crucial role in marketing, industrial and tech- nical fields. Twenty years ago, standardization was the realm of just a few specialists.Today, compa- nies treat standardization as a technical and com- mercial element of great importance. At the same time, companies have realized they must play an active role in the standardization field,and they must be ready to accept standards made without their agreement.Therefore,it is also increasingly necessary for engineers and decision makers in en- terprises to study the purpose and application of standards and standardization, and to optimize their enterprises’ position by doing so.  相似文献   

2.
Traditional Chinese Medicine (TCM) is the medical science based on theories and practicing experience of traditional Chinese medicine to study transferring principles of health and sickness, as well as prevention,diagnosis, treatment, rehabilitation and healthcare.TCM is marked with its long history of development, integrated theory system and abundant practicing expenence.  相似文献   

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Cotmtless studies have been conducted by large number of femi- nist researchers and feminist media scholars to analysis feminism, ideology, women's magazines and the relationship among them. There are endless discuss and debates about 'what means to be woman' since the society's conception of woman, the historical perspective, and women's self-perception about themselves are far-reaching within the river of history. Klevin (1971) points out that feminine character- istic are almost entirely related to its culture, society and history. Women have always been pushed to the 'second place in the world when men have occupied the first place in most cultures. However, this position, Millum (1975) also argues, has nothing to do with women's 'natural feminine characters'. The main reason is relates to the irresistible social tradition, environmental forces and sometimes educational background as well.  相似文献   

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The modern Olympic Movement has been con-necting people of different nations,ethnicities andcultural backgrounds in competitive sports,and hasexerted a profound influence on human civilization.As a sports phenomenon,the Olympic Gamesis the most fascinating sports arena in which  相似文献   

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In this paper, we present inorganic–organic hybrid coatings with polymer matrix (water soluble) that contain silver nanoparticles (AgNPs). The structure and morphology of coating materials were determined by infrared spectroscopy (FT–IR) and scanning electron microscopy (SEM). Therefore, the antimicrobial activities and mechanisms of coatings for several pathogenic bacteria (Bacilius cereus and Staphylococcus aureus) were investigated. It was demonstrated that the obtained material with silver nanoparticles keep their antimicrobial effect even if they are subjected to several cycles of washing with water and detergent.  相似文献   

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Metal and nitride coatings of high-entropy alloys (HEA) having different phase compositions produced by different methods were investigated. It is shown that for the high-entropy coatings is characteristic the presence of the nanostructured state, which in parallel with the cluster structure provides hardness for metal coatings ~ 10–19 GPa; for nitride coatings are characteristic 50–60 GPa and the modulus of inelastic buckling more than 300 MPa. The relation of the lattice parameters, which are defined experimentally, to the parameter of the lattice of the most refractory metal in the HEA reflects the level of the elastic modulus relative to the theoretically possible both in the cast HEA and in metal coatings on their base.  相似文献   

11.
The on-going depletion of the oil reserves leads to the needs for development of sustainable and renewable energies. Between fossil and solar eras,low carbon natural gas and clean coal become the most crucial intermediate alternatives as energy source and feedstock to produce chemicals.In meantime,lignocellulosic biomass will play the role as fuel or as raw material,especially for the future decades.This is of ultimate importance for the countries with increased demands for energy in a portable form and for synthetic materials,such as China. New catalytic materials are at the heart in the processes(existing and innovative)to converting natural gas or coal,the nonportable or non-pumpable energy carriers,to liquid form,and to upgrading less valuable to more value-added chemicals for a particular market requirement.In many instances,innovation of a new catalytic material makes a new process from dream to reality,and in the other cases,the need for a new process catalyzes the research for a new catalytic material. The process and material("chickens and eggs")interplay propels the recent advances in hydrogen fuel,GTL,CTL,CTC,SNG and BTL technologies.In this growing market,Siid-Chemie has not only strengthened its market presence,but also consolidated its position as the worldwide technology alytic materials in the new chemical processes,such as ShiftMax(R),ActiSorb(R),AmoMax(R),MegaMax(R),DME-1(R),FAMax(R),and MTPro-1(R).Siid-Chemie commits to provide the best performing tailored catalytic materials to the matching processes.  相似文献   

12.
Multivariate analysis and calibration in spectroscopy have been widely used in many fields of applications in recent years. The number of components to use in such applications for sufficiently describing the spectra is dependent on the stability of positions of the peaks of interest. Unwanted shifts give rise to a more complex model, i.e., more components. Various kinds of shift correction can be applied as preprocessing tools to cope with these effects. In this paper we describe a general concept of how to model intensity (peak height) and position as separate phenomena. We described methods and theory from image modeling, and apply them on one-dimensional signals such as traditional Raman spectroscopy.  相似文献   

13.
Microbiologically influenced corrosion caused by sulfate-reducing bacteria(SRB) poses a serious threat to marine engineering facilities.This study focused on the interaction between the corrosion behavior of two aluminum alloys and SRB metabolic activity.SRB growth curve and sulfate variation with and with aluminum were performed to find the effect of two aluminum alloys on SRB metabolic activity.Corrosion of 5052 aluminum alloy and Al-Zn-In-Cd aluminum alloy with and without SRB were performed.The results showed that both the presence of 5052 and Al-Zn-In-Cd aluminum alloy promoted SRB metabolic activity,with the Al-Zn-In-Cd aluminum alloy having a smaller promotion effect compared with 5052 aluminum alloy.The electrochemical results suggested that the corrosion of the Al-Zn-In-Cd aluminum alloy was accelerated substantially by SRB.Moreover,SRB led to the transformation of Al-Zn-In-Cd aluminum alloy corrosion product from Al(OH)3 to Al2 S3 and NaAlO2.  相似文献   

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Formation and Oxidation Behavior of Al—Cu—Fe Quasicrystal   总被引:3,自引:0,他引:3  
Al62.5Cu25Fe12.5 alloy was prepared by arc melting .It was found that the formation of quasicrystalline phase is related to the condition of annealing,such as temperature and duration.Weight gain of Al-Cu-Fe quasicrystal during the oxidation at 700 and 800℃ in dry air was measured by means of thermal balance.The oxidation kinetics showed that the quasicrystal has good oxidation resistance.Only α-Al2O3 was formed on Al62.5Cu25Fe12.5 quasicrystal.The surface morphologies of Al-Cu-Fe quasicrystal after isothermal oxidation for different times were observed.  相似文献   

15.
A strong contributory factor impacting the market for seals and sealing products is that of the changes within the world pumps industry. According to a companion report to this publication, the world pumps market has reached US$19 billion per annum. This article provides an overview and market forecast for the sealing products serving this market. It looks at the world pump market and how it closely relates to that of sealing products.  相似文献   

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The detection of defects in materials and components using ultrasonic nondestructive testing and evaluation techniques is of interest in many industrial areas. Reliable defect detection requires defined and reproducible scanning of the probes along the surface of the components. For post-processing of the recorded rf-data the Synthetic Aperture Focusing Technique SAFT has been successfully applied to improve the performance of ultrasonic testing. For specific defect and component configurations, the Time-of-Flight Diffraction technique TOFD has also been successfully applied for quantitative evaluation of crack sizes. This contribution reviews developments and applications of SAFT and TOFD with reference to representative examples from the past and the present.  相似文献   

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Measurements of ultrasonic velocity in creep damaged material are reviewed. The influence of damage on ultrasonic velocity is analysed and the relation between them is derived. It is shown that measurements of ultrasonic velocity can be used to predict the remaining life. Measurements of ultrasonic velocity in a damaged beam are presented along with measurements of the ultimate strength. A relation is found to exist, between reductions in ultrasonic velocity and ultimate strength, which might be used to assess the load carrying capacity of a structural element.  相似文献   

18.
Introduction Security standards,while not a panacea,play a crucial role in helping practitioners and managers to work with the complexity of today’s technology and business  相似文献   

19.
The sea environment is the most structurally hostile of environments within which aircraft operate. Naval aviation operations routinely expose structural components to salt spray and high loads, especially during landings. The result is component lives occasionally end prematurely due to corrosion-assisted fatigue, or fatigue with other compounding factors. The occurrences of these unplanned events increase with the number of years an aircraft remains in service. The susceptibility of aging aircraft to structural demise demands that we institute a paradigm shift to our approach to designing, maintaining and managing metallic aircraft structures subjected to repetitive loads and corrosive environment. Is corrosion and fatigue research heading in the right direction to solve real and potential problems in aging naval aircraft?This paper provides an overview of how we validate and assess service life. The key issues involved in managing life-critical parts during their operation are the adjusting of inspections, and the effect of operational discoveries of flaws or failures, which disrupt our perceptions of the structural condition, on total life designation. The management issues with respect to an aging operation fleet of naval aircraft will be described from the view of the structural life management team. Research in corrosion and fatigue of metals must answer to the tactical aircraft manager's needs. For structures and materials research to transition into practice, it must focus on producing data and test results useful for making life decisions.  相似文献   

20.
Thermal expansion behaviors of some precursor-derived amorphous Si-C-N and Si-B-C-N ceramics, which were shaped by plastic forming after crosslink, were studied. To complete the shrinkage and densification, after thermolysis specimens were heat treated at a temperature of 1400℃ for 10 h in nitrogen atmosphere. The thermal expansion coefficient of VT50-derived amorphous Si-C-N ceramic increases from 1.98×10-6/K at 400℃ to 3.09×10-6/K at 1000℃, of NCP200-derived amorphous Si-C-N ceramic increases from 2.35×10-6/K at 400℃ to 3.45×10-6/K at 1000℃, and of T2-l-derived amorphous Si-B-C-N ceramic increases from 2.08×10-6/K at 400℃ to 3.18×10-6/K at 1000℃. No glass transition for these amorphous ceramic materials was detected, indicating that as-thermolyzed precursor-derived Si-(B-)C-N ceramic materials are amorphous solids, but not glasses.  相似文献   

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