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1.
“Low-Tech” Innovations   总被引:1,自引:0,他引:1  
This paper is about an industrial sector which, according to the usual socio-scientific indicators, is referred to as “low-tech”, respectively as non-research intensive and which mostly comprises “traditional” industries. The interest in this sector is motivated by the contradictory situation that, on the one hand, the debate about the perspectives of modern societies focuses on the rapidly growing importance of technological innovations, knowledge and research-intensive economic sectors while, on the other hand, traditional industries make up a considerable fraction of employment and production, especially also in developed economies. On the basis of the results of extensive empirical research, this contribution tries to find answers to the basic question, whether one can speak of an innovation mode typical of the low-tech sector. The institutional based innovation systems approach forms the categorical basis of the analysis. In order to elucidate the specific features of low-tech innovations, they are, in conclusion, compared to the general characteristics of high-tech-based innovation processes.  相似文献   

2.
An analysis of the dispersion of elastic waves is presented for two types of long ultrasonics wave-guides that we qualify of “bimorph”: (i) a “three-layer” guide made of two different materials and (ii) a “clad core” guide built up of a rectangular core surrounded by a cladding, the materials of the rod and cladding having different properties. An analytical model is proposed to describe the extensional, flexural and torsional motions in “bimorph” wave guides having two geometrical and material symmetry axes. The asymptotic behaviour of the model allows one to select the material properties which lead to modes guided essentially either in the central layer or in the core of the bimorph guide. Moreover, the dispersive properties of a “bimorph” can be controlled through the choice of geometrical and material parameters.  相似文献   

3.
At the outset a brief background from a pharmaceutics perspective is presented here. Pharmaceutical industry is one of the most tightly regulated industries. Statistics naturally plays an important role in the implementation of the compendial, regulatory and in-house requirements. The minimal requirement consists of a set of basic statistics, such as mean and standard deviation (SD), associated with each group of sample experimental data intended for submission. However, not only each statistic is individually subjected to a set of compendial, regulatory and in-house specifications, but also the individual observation is required to be within specific range for compliance (e.g. content uniformity). Hence these basic statistics are often referred to as the stand-alone sample (SAS) statistics, meaning that each statistic has to meet its own requirements. In this context, the geometric mean is indeed a SAS statistic. It is meaningful and interpretable directly from its face value. The geometric standard deviation (GSD) as derived in ref(B) is also a (SAS) statistic. It is meaningful and easily interpretable directly from its face value. It has the same sample information and the same interpretation as that of the regular SD. Sometimes, it shares essentially the same magnitude as the regular SD. Besides, it also has essentially the same magnitude as that of the jackknife GSD statistic, GSD(JK). For decades, these geometric statistics have been in practice, particulary, since the author of ref(B) was a member of the USP In-Vitro Bioavailability Testing Subcommittee (1970-1975). It has also been accepted fully and freely by the above-mentioned over-sight agencies.  相似文献   

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If due to the market analysis a company makes the decision for the production of a new product by application of soldering and special the soldering with temporarily liquid solder, this one is then made specifically after that the company specific construction and production preparation. Either the decision for soldering is technically and/or economically well‐founded or she is even unavoidable by so‐called mixed material connections in the assemblies. This hybrid design finds application increasing today. In the contribution on hand the analysis and assessment of the soldering theory and practice is carried out under the point of view of the possible production of “ideal soldered connections” and “optimal soldered connections”.  相似文献   

6.
Turbomolecular pumps are gradually gaining ground in the hard industrial processes. In this article a statement is made on the use of the turbomolecular pumps as to final evacuation of the TV tubes. In particular the high qualification of the pumps is emphasized. Furthermore, the advantages are shown compared with the conventional diffusion pump system.  相似文献   

7.
The bioavailability of eight nitrofurantoin tablet formulations differing in technological respects has been evaluated and correlated with de dissolution curves obtained using USP XXI Ed methods I and II. Method I was found incapable of predicting bioavailability of formulations when Carbopol 934 is used as binder. The influence of the technological factors varied is discussed.  相似文献   

8.
A rational approach to dealing with the problems created by developing technologies requires a new account of what is involved in proper management. A tripartite distinction is introduced between being reasonable, being rational, and having style. These notions are based on the commonsense principle of rationality (CPR), to be rational one must learn from experience. The proper management of technology requires more than learning from experience (being rational) and having the proper goals (being reasonable); it requires style, which entails being reasonable and acting in accordance with a given standard systematically over time.  相似文献   

9.
Small amounts (up to 0.1%) of C60 and C70 have been detected by high-pressure liquid chromatographic (HPLC) analysis of toluene extracts from soots used to manufacture Chinese ink sticks, or Sumi. These soots have been prepared by slow burning of pine wood, and later various seed oils. Turpentine oil, the major constituent of pine wood oil, have been found to produce twice as much fullerenes as does toluene when used as the combustion material. The yields of fullerene from unsaturated combustion materials decrease with the iodine number, reaching zero in the saturated compounds. Possible role of fullerenes as the effective gloss enhancer for black color is suggested in reference to the known technique of adding a natural red pigment to Sumi practiced in Japan.  相似文献   

10.
Smart coatings for intelligent surfaces The manufacturing of intelligent surfaces according to examples in nature is an important research topic for the near future. Nowadays several coatings exist which are able to adapt their properties to environmental conditions. Prominent examples are windows with switchable transmission or self‐cleaning surfaces based on photocatalysis. Novel thin films exhibiting excellent tribological as well as sensoric properties open new ways for the future design of driving components. Examples are diamond‐like carbon films which can be used as extremely hard force sensors. They are able to detect and influence the state of surfaces under mechanical load. There is a huge variety of potential applications for such sensors.  相似文献   

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《Mauerwerk》2018,22(2):126-127
This publication concerns the differentiation between the terms ”confined masonry“ and ”infill masonry“ using the example of the national technical approval Z‐17.1‐1145 – POROTON S9 MW –vertically perforated clay units with integrated thermal insulation using thin layer mortar [1].  相似文献   

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A wide family of cellulose‐based additives are authorized worldwide as fillers and thickening agents in foods, pills, and tablets, and microcrystalline cellulose (MCC) is, among these, the most important one. Since MCC manufacturing is similar to the main production route of cellulose nanocrystals (CNCs), it is reasonable to wonder whether the MCC would contain CNCs as minor components. In this Short Communication, we provide first results about the occurrence of CNCs in MCC, observed by dynamic light scattering and transmission electron microscopy after serial filtrations of MCC suspensions. The incidence of cellulose nanoparticles has been proved in several different trials in our ongoing works on diverse MCC samples, and the nanoparticles isolated showed shape and dimensions similar to those commonly produced by acidic hydrolysis at laboratory level. Therefore, the presence of CNCs in many products is considered as a certainty. The foods and the pharmaceuticals we have been consuming so far do indeed contain traces of CNCs to such an extent that this wide presence in consumed products should be taken into account when considering possible limitations of the use of these nanoparticles in food contact materials manufacture.  相似文献   

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Membranes in cells display elaborate, dynamic morphologies intimately tied to defined cellular functions. Cisternae stacks are a common membrane morphology in cells widely found in organelles. However, compared with the well‐studied spherical cell membrane mimics, cisternae stacks as organelle membrane mimics are greatly neglected because of the difficulty of fabricating this unique structure. Herein, the grana‐like cisternae stacks are assembled via the reorganization of stacked microsized bicelles to mimic grana functions. The cisternae stacks are connected by fusion regions between adjacent cisternae. The number of cisternae can be controlled from ≈4 to 15 by the variation of ethanol volume percentage. Under the stimulation of solvent or negatively charged nanoparticles, the cisternae stacks can reversibly compress and expand, similar to the “breathing” property of natural grana. During the “breathing” process, nanoparticles are reversibly captured and released. Frequency resonance energy transfer is realized on the cisternae stacks trapped with two kinds of quantum dots. The cisternae stacks provide advanced membrane model for cell biotechnology, and clues for the shaping of organelles composed of cisternae. The ability of the cisternae stacks to capture materials enables them to possibly be applied in biomimetics and the design of advanced functional materials.  相似文献   

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We discuss the applicability of some elementary models for the closure of in vitro “wounds” that are inflicted in monolayer cell cultures (also termed “wound healing assays”). These models can be applied to the simulation of healing of superficial wounds as long as they only concern the epidermis. We test several models that are based on a curvature driven displacement, a simple partial differential equation based model in which the actual cellular density is tracked. Finally, a semi‐stochastic cellular based model is evaluated.  相似文献   

19.
Lithium metal is an ultimate anode in “next‐generation” rechargeable batteries, such as Li–sulfur batteries and Li–air (Li–O2) batteries. However, uncontrollable dendritic Li growth and water attack have prevented its practical applications, especially for open‐system Li–O2 batteries. Here, it is reported that the issues can be addressed via the facile process of immersing the Li metal in organic GeCl4–THF steam for several minutes before battery assembly. This creates a 1.5 µm thick protection layer composed of Ge, GeOx, Li2CO3, LiOH, LiCl, and Li2O on Li surface that allows stable cycling of Li electrodes both in Li‐symmetrical cells and Li–O2 cells, especially in “moist” electrolytes (with 1000–10 000 ppm H2O) and humid O2 atmosphere (relative humidity (RH) of 45%). This work illustrates a simple and effective way for the unfettered development of Li‐metal‐based batteries.  相似文献   

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