Наклеп при накатке отверстий

Tolerancing has long been identified as a crucial part in the development of optical systems. It aims at finding the best balance between quality and cost as tolerances closely tie together manufacturing expenses and performance. Tolerance effects have been included into the optimization function (merit function) by some lens designers to find insensitive designs1-5 and frequently compensators are employed to further improve the performance of assembled lenses. Compensators are limited to a small number of system parameters, but selective assembly of components can extend the number of parameters available for compensation. It can be employed to reduce tolerance effects of disturbed parameters by finding the best matches out of a set of components. In this work we discuss how desensitization and selective assembly can be combined to loosen tolerances and increase as-built performance. The investigations concentrate on tolerance insensitive design forms under the presence of selective assembly compensators. In contrast to desensitizing a given lens or introducing new design means we focus on introducing new assembly strategies into the design procedure and investigate how using selective assembly as a compensator while desensitizing the remaining design parameters can lead to even less sensitive designs

Нижний кембрий Западного Саяна

A miniaturized solid state laser for marking applications has been developed featuring novel assembly strategies to reduce size, cost and assembly effort. Design and setup have been laid out with future automation of the assembly in mind. Using a high precision robot the optical components composing the laser system are directly placed on a planar substrate providing accurate positioning and alignment within a few microns. No adjustable mounts for mirrors and lenses are necessary, greatly simplifying the setup. Consisting of either a ND:YAG or a Nd:YVO4 crystal pumped with a fiber coupled diode laser, a q-switch for pulse generation and a beam expander the entire assembly is confined in a 100ml space and delivers 4 W of continuous output power at 1.064 ?m with an efficiency greater than 40%. Pulse lengths of 10-20 ns and repetition rates of up to 150 kHz have been obtained with an acousto-optic modulator. In addition, a custom designed electro-optic modulator with integrated high voltage switch has been realized. A supply unit for the entire system, including scanner and water cooling, is integrated in a 19" industrial chassis and can be operated via a graphical user interface on a standard personal computer

Общие вопросы развития электроприводов современных металлорежущих станков

Besides their high efficiency and compact dimensions high power diode laser systems feature the modularity to from different beam shapes adapted to the respective application. So apart from the development of diode laser systems concerning the increase of output power and beam quality, another approach is the special assembling of individual diode laser bars to build up modular systems for new direct diode applications. Despite the limited but often sufficient beam quality of this modular approach it offers many advantages in applications like simultaneous polymer welding, laser cutting, laser welding and hardening of metals

Оптимізація макрологістичних мереж

We report on a Laser source, emitting in the mid-IR spectral range. A mode-locked Nd: YVO Laser is used as a pump Laser, followed by two nonlinear frequency conversion steps (OPG, DFG). The broad-band output beam is tunable between 9 ?m and 13 ?m, with average powers up to 10 mW. Further extension of the tuning range is possible

Исследование пластифицирующих свойств некоторых производных карбазола

During the assembly of customized miniaturized solid-state lasers, robot based operations can significantly reduce cycle times and improve performance and quality. Automation of the resistance soldering technique for optical components based on planar technology described in the previous work of Dolkemeyer et. al can be self-optimized to compensate component and process tolerances, cope with different element geometries and therefore reduce planning efforts and facilitate the operator's work.solder pads. Planar adjustment of an optical element and exemplary resistance measurement during soldering process For the automation of the soldering process itself the modification of the system's electrical resistance is measured since this value can be calculated by evaluating the process parameters without supplementary equipment. In addition, it can be used as a documented quality control. The increase of the resistance at the solder's melting point is related to the length of the molten zone and is always continuous even if current and voltage are discontinuous. Presented are the technique for planar adjustment and current results of the automation and self-optimization process

‘X Journalism’. Exploring journalism’s diverse meanings through the names we give it

In this article we propose the notion of X Journalism as an observational tool and concept. It owes its existence to a simple observation: the evolution of journalism is accompanied by the emergence of ever-new journalism-related terms, i.e. combinations of the word ‘journalism’ with a particular modifying term that represents and signals a certain specificity and novelty. Examples include ‘robot journalism’, ‘foundation- funded journalism’, ‘cross-border journalism’, or ‘solutions journalism’ – just to name a few. To date, we have collected and mapped 166 X journalisms and have ‘crowd- categorized’ them into clusters according to the different aspects they refer to. We explore X Journalism as a concept, present our mapping, and show how it can help to cope with journalism’s increasing complexity, grasp the diversity of the field, trace its constant evolution, as well as identify patterns and interrelations between these different movements and occurrences. Through a test case of audience-related X journalisms we demonstrate an empirical application before illustrating the theoretical compatibility of X Journalism and suggesting a research agenda that highlights potentials for X Journalism-driven studies.<br/

Исследование активности хромо-оловянных катализаторов для окисления SO2 в SO3

Целью настоящей работы является исследование активности каталитической системы Cr[2]O[3]+SnO[2] в широких пределах соотношений между двумя ее исходными компонентами

A process for the alpha-monoalkylation of arylacetonitriles, arylacetoesters and arylacetic acids.

A process for the alpha-monoalkyaltion of arylacertonitriles, arylacetoesters and arylacetic acids with dialkyl carbonates in the liquid phase, in the presence of bases at temperatures ranging from 100 to about 270 °C

Inhabiting warm microhabitats and risk-spreading as strategies for survival of a phytophagous insect living in common pastures in the Pyrenees

[EN] The breakdown of the transhumant grazing system in the Spanish Pyrenees has led to a severe decline in the area of pastures. However, in the high mountain zone there are still large areas of species-rich grasslands. The aim of this study was to assess the oviposition preferences of the shrub-feeding Blue-spot hairstreak, Satyrium spini (Denis & SchiffermÃller, 1775), in montane common pastures in the Spanish Pyrenees and recommend a way of managing these grasslands that favours this species. Our study showed that females of S. spini laid their eggs on Dwarf buckthorn (Rhamnus pumila Turra) and Alpine buckthorn (R. alpina L.), which are novel host plant records for Spain. A warm microclimate was of crucial importance for egg-laying. Occupied plants grew mostly at sparsely vegetated grassland sites where there were large patches of bare rocks, stones or gravel. Most egg batches were laid close to the ground and 75% consisted of only one egg. The number of batches per R. pumila plant was higher on east-, southand west-facing slopes than on north-facing slopes. Presence of eggs and the number of egg batches per R. pumila plant were best explained by a long sunshine duration. At high altitudes particularly warm microhabitats seem to be more important for S. spini than at lower altitudes in Central Europe. We assume that the preference for unusually warm microhabitats is explained by the cold climatic conditions near the altitudinal range limit of the species. That most of the eggs were laid singly and not in small batches as in Central Europe might be a risk-spreading strategy to cope with the harsh climatic conditions and the high inter-annual variation in weather conditions in the high mountain zone in the Pyrenees. The best way to maintain open grasslands for S. spini and other thermophilous grassland species in the high mountain zone of the Pyrenees is to use the traditional combination of sheep and cattle grazing.Peer Reviewe

PROCESSO PER ALFA-MONOALCHILAZIONE DI ARILACETONITRILI

Si descrive un procedimento per l'alfa-monoalchilazione di arilacetonitrili con dialchilcarbonati in fase liquida, in presenza di basi a temperature comprese fra circa 100 DEG C e circa 250 DEG C