bluuebunny/crossref_metadata_2025_split huggingface dataset:
Begasen von niedrigviskosen Flüssigkeiten
Authors: Judat Helmut 
Published: May 2005

AbstractGassing of low‐viscosity liquids. The gassing of low‐viscosity liquids is a basic operation frequently encountered in practice; various kinds of apparatus have been developed depending upon the gas load. Of particular importance are the stirred tank and the bubble column because most chemical reactions in the gas/liquid system are performed in these apparatus. This paper is therefore concerned with basic chemical engineering data essential for optimum design of such equipment. Particular attention is devoted to questions of minimum gas throughput. energy requirements, and attainable mass transfer, a distinction being drawn between coalescing and non‐coalescing conditions.
Ionenaustauscher und Adsorber — vielseitige Hilfsmittel der chemischen Industrie
Authors: Martinola Friedrich 
Published: May 2005

AbstractIon exchangers and adsorbers – versatile aids in the chemical industry. Ion exchangers and adsorbers are nowadays available in such a wide range of universally applicable or specialist products that they are widely used in industrial chemistry. New applications are discovered each year. Hence their originally predominant use in water treatment has meanwhile been extended and diversified by numerous further applications.
Digitale Prozeßautomatisierungssysteme
Authors: Wüchner Werner 
Published: May 2005

AbstractDigital process control systems. We are currently witnessing a technical revolution instigated by the microprocessor, which is considerably changing our methods of process control and the design of control rooms. The modern control room presents an entirely different man‐machine interface. CRT's with keyboards and/or light pens for plant control and operation are now to be found instead of instrumental boards. This paper describes the architecture and mode of operation of this new generation of process control systems.
Zur Reaktionstechnik der anaeroben Fermentation
Authors: Wandrey Christian , Aivasidis Alexander 
Published: May 2005

AbstractChemical reaction engineering of anaerobic fermentation. Anaerobic fermentation has already been used for more than 50 years for the disposal of excess activated sludge. In recent years, increasing costs and considerable problems encountered in connection with the disposal of activated sludge have encouraged the development of anaerobic processes for the treatment of industrial waste water. Various aspects which have to be taken into account when planning a digester plant are discussed. Reduction in residence time with concomitant increase of biogas production rate is possible by retention of biomass. In this way catabolic performances are obtained comparable to those of aerobic high capacity activated sludge plants. Anaerobic waste treatment appears so far to be a real purification method because the predominant part of the organic pollution (more than 95%) is eliminated under energy saving conditions. The by‐product biogas contributes to the energy self‐sufficiency of the process.
Temporärer Korrosionsschutz von Ausrüstungen für den Bau von Großanlagen außerhalb Mitteleuropas
Authors: Wüstenberg Dieter 
Published: May 2005

AbstractTemporary corrosion protection for plant construction equipment outside of Central Europe. „Temporary protection against corrosion”︁ consists of measures for the prevention of damage to equipment by corrosion within a given limited period of time. Essentially, it consists in the protection of machinery, apparatus, fittings, pipelines, measuring and control equipment etc. against atmospheric corrosion in the time between the fabrication of such equipment by the manufacturer and its assembly or commissioning by the firm who is to run the plant. A guaranteed protection against corrosion for a period of two years and more is not unusual. Apart from corrosion, the equipment is also subject to mechanical wear and tear. Worth mentioning here are wear and tear due to, inter alia: buffering during transport by rail; rolling during transport by ship; bending and knocking during loading and unloading; compression during stacking in ships holds and in wharehouses; vibration during transportation. These, in part, quite considerable mechanical stresses which the equipment is subjected to should be taken into account, on the one hand when constructing and installing the equipment, and, on the other, when protecting the equipment against corrosion and when packing.
Wechselbeziehungen zwischen Physikalischer und Technischer Chemie
Authors: Wicke Ewald 
Published: May 2005

AbstractInteractions between physical and industrial chemistry. The most important interactions for the two areas of chemistry are found in the following three fields: (1)states of materials (states of aggregation) and thermodynamics; (2) kinetics of molecular processes as a basis for macroscopic models; (3) methods of testing and measurement and development of equipment. The „classical state”︁ of each of these areas is first sketched out and then the principal developments which are still in course of flux; directions of future development are then deduced. Such directions are exposed to be: extension of the scope of application of supercritical states as solvents and reaction media, as part of a general expansion of industrial application of elevated pressures; increase in knowledge of nonlinear dynamics of chemical systems with regard to transient behaviour and control mechanisms; increase in basic research on molecular structure and dynamics at the interfaces of dispersed systems – especially micelles and catalyst surface – using „in situ”︁ methods, and more extensive utilization of the results in industrial chemistry.
Werkstoffverbund durch heißisostatisches Pressen (HIP)
Authors: Nissel Christoph , Seilstorfer Helmut 
Published: May 2005

AbstractBonding of material by hot isostatic pressing (HIP).The HIP process is presented and its applications are described. One of these applications is the gas pressure bonding, which opens up new possibilities in joining materials. The process and the possibilities are demonstrated by some examples. In comparison with other joining techniques, gas pressure bonding is a flexible process. Also the production of parts is possible with little or no machining. The strength of the joint corresponds to the strength of weakest material of the joint if there are no brittle phases. In this case the formation of these phases can be prevented by choosing appropriate parameters, thus ensuring a strong bond.
Chemische Methoden der Abwasser‐Aufbereitung
Authors: Simmler Walter 
Published: May 2005

AbstractChemical methods of waste‐water treatment. Chemical methods of waste management by oxidation can be considered for particular effluents whose constituents are degraded too slowly in conventional sewage treatment plants or which interfere with the biodegradation of other substances. Of these methods, those we have to choose from today are, in order of increasing operating temperature: oxidation with hydrogen peroxide – wet oxidation at high pressure – evaporation and combustion. None of these methods is fundamentally better than the others, i.e. none has a maximum ecological benefit coinciding with a minimum economic impact. Detailed experimental work is required to establish the limits and possibilities in each case and thus to form a basis for useful comparisons. Thermal processes are normally ruled out for low concentrations of degradable constituents in waste water because the specific energy costs per unit volume are too high; this is where hydrogen peroxide may offer advantages, especially when the proportion of these constituents fluctuates. With higher concentrations, wet oxidation can be employed; evaporation and combustion are suitable if there is also a high concentration of inorganic salts.
Schwingungserscheinungen in Chemieanlagen
Authors: Gaube Erwin 
Published: May 2005

AbstractVibrational phenomena in chemical plant. This article draws on the practical experience of the author to provide a survey of vibrational problems in chemical plant and of their sources. Even though it is not always possible to eliminate all potential sources of vibration by appropriate calculation and design measures during the planning stage, they can usually be quickly identified subsequently by suitable measuring techniques and countermeasures adopted.
Stand und Trend bei der Gesetzgebung zur analytischen Erfassung der Abwasser‐Inhaltsstoffe
Authors: Olivier Manfred , Schendel Frank‐Andreas 
Published: May 2005

AbstractCurrent status and future trends in legislation for the analytical determination of the constituents of waste water. If national and supranational regulations are to be translated into enforceable water law (e. g. national water codes), then all those concerned must work together effectively. Experience in recent years gives reason to hope that legislators will take more careful account of scientific factors in the future. The problems of waste‐water analysis are described in the light of the parameters of the waste‐water levy act. The determination of settleable substances serves as a typical example of what is, from the analytical point of view, an unsuitable parameter; the chemical oxygen demand (COD) is determined in accordance with a precisely specified convention. The problems of trace analysis are illustrated in the determination of the heavy metals mercury and cadmium. In the fish test, the peculiarities of biological test methods are demonstrated. In order to ensure that the results of analyses are reliable, it is essential that sampling and preservation be both objective and problem‐related. In the long term, it is important to find ways of reducing the work involved to an acceptable level without any serious loss of information.
Membrandestillation
Authors: Schneider Klaus , van Gassel Thomas Johannes 
Published: May 2005

AbstractMembrane distillation. In the membrane distillation process, two aqueous liquids of different temperature border on the two lateral surfaces of a hydrophobic (non‐wettable) membrane. The vapor pressure difference resulting from the temperature difference causes vapor molecules to be transported through the pores of the membrane, comparable to an evaporation, transport, and condensation process in distillation. The dependence of this process on various process parameters, possibilities of energy recovery, and application in the fields of pure water production, evaporation of solutions, and recovery of valuable substances are reported.
Sicherheitsbetrachtungen bei der Planung von Chemieanlagen
Authors: Tröster Erwin 
Published: May 2005

AbstractSafety considerations in the planning of chemical plant. The author shows how the safety concept of a chemical plants is developed on the basis of the process, the properties of the materials, the operating conditions, and the plant location. The basic considerations for a complete and balanced safety concept are addressed. It is demonstrated how, in the case of a large chemical facility, safety considerations undertaken in up to three stages can already ensure the necessary high safety level of a chemical plant during the planning stage.
Die Verfahrensentwicklung im Spannungsfeld zwischen sich rasch entwickelnden Rohstoff‐ und Produktpreisen
Authors: De Beuckelaer Gerard 
Published: May 2005

AbstractProcess development in a atmosphere of rapidly changing prices of raw materials and products. A computer program that allows the analysis of the economic consequences of alternative routes in process development is presented. The program communicates via a user friendly menu system. Single process steps, stored in the data base, can be combined to give systems of almost any desired level of complexity. The advantages and the scope of the program are illustrated by means of two examples.
Mechanische Trennung von Bioprodukten
Authors: Bender Wolfgang , Koglin Bernd 
Published: May 2005

AbstractMechanical separation of bioproducts. A great variety of processes and equipment are available for mechanical separation of particles from liquids which have proved of value in the chemical industry or in water treatment. Only a small selection of this broad spectrum of sedimentation, filtration, or flotation processes and equipment can be considered for bioproducts – the limiting factor being the unfavourable separation properties. Only slight differences in density, small particle sizes, and the high compressibility of the filter cakes also require very careful adaptation to the specific separation task.
Abwasserüberwachung als vorbeugender Gewässerschutz
Authors: Frech Thomas 
Published: May 2005

AbstractMonitoring of liquid effluents as preventative protection of natural bodies of water. One possibility to improve the safety of river water cooling systems is to control the river water side of the cooling system continuously by process analyzers. In this way, leakages in cooling systems can be recognized earlier and the amount of products which contaminate the river water can be minimized. The aim of this article is to inform the user of water cooling systems about the process analyzers which are available. A second aim is to help him to decide which of these analyzers is the best for his measuring problem.
Die Arten der rißbildenden Korrosion und ihre Bedeutung für die Betriebsbereitschaft von Komponenten der Chemietechnik
Authors: Gräfen Hubert 
Published: May 2005

AbstractKinds of crack‐producing corrosion and their significance for the availability of components of chemical plants. Interor transcrystalline cracks in metallic components of chemical plants can occur under the combined influence of mechanical stress and corrosion. Since they usually remain unrecognized before the occurrence of visible damage – leakage of a vessel or fracture of a structural part – such crack‐producing corrosion processes are greatly dreaded. Based on differences in the mechanism of the process of damage, one distinguishes two groups, i. e. stress corrosion cracking (SCC) and corrosion fatigue (CF). SCC stands for an interaction between local corrosion attack and quasi‐static tensile stresses (load‐ and/or residual stresses). CF means a combination of mechanical stresses differing in time and corrosion. Hydrogen induced SCC is a special kind of crack corrosion, initiated by atomic hydrogen absorbed in a metal. The paper describes the different systems of SCC and CF, the forms of failure, the parameters, and the possibilities of avoiding damages, especially emphasizing their significance in practice.
Durchflußkontrolle kleiner Dosierpumpen bei stetiger und pulsierender Strömung
Authors: Vetter Gerhard , Christel Wolfgang 
Published: May 2005

AbstractFlow control for small metering pumps with continuous and pulsating flow. Metering of small flows with high discharge pressure is performed mainly by displacement metering pumps. The necessary mass‐flow control shows problems with pulsating piston‐ or diaphragm metering pumps. A survey explains the presently available continuous and discountinuous methods of mass‐ and volume flow control. Special investigations have been performed with differential scales and mass flow meters based on the Coriolis‐ and the thermal principle. The differential weighing method shows good accuracy down to minimum mass flows of 0.1 kg/h. This method is expensive and requires vibration protected installation. The Coriolis flow meter, applicable over a similar range, precisely integrates the pulsating signal, but requires damping or signal averaging for regulation purposes. Thermal flow meters prove rather sensitive to temperature fluctuations. Under stable conditions and with proper calibration this principle may be applied to flows even below 0.1 kg/h.
Kraftwerke auf der Basis der zirkulierenden Wirbelschicht‐Feuerung
Authors: Hafke Carl , Plass Ludolf , Bierbach Herbert 
Published: May 2005

AbstractPower stations based on circulating fluid bed combustion. The atmospheric circulating fluid bed (CFB) combustion process for the generation of steam and electric energy must be regarded as fully established and commercially proven based on operating results and plant availabilities achieved to date. This process is especially suitable for the combustion of low‐quality fuels in cases where stringent pollution standards have to be met. Because of a new combustion technique, reduction of emission takes place in the combuster itself (integrated environmental protection), which eliminates the need for flue gas scrubbers. The sole by‐product of a CFB boiler system is a fine, dry ash, which can either be used in the building industry or may be dumped without any problem.
Verfahrensentwicklung durch Kombination von Prozeßsimulation und Miniplant‐Technik
Authors: Buschulte Thomas K. , Heimann Frank 
Published: May 2005

AbstractEfficient Process Development by Combining Process Simulation and Miniplant Technique. International competition, growing ever fiercer, and product life cycles which are becoming shorter all the time demand a significant contraction times from the chemical industry, of the implementation times from the conception of a product to its market introduction. A significant contribution to rapid and cost‐effective detailed planning of a new production process is provided by the combination of process simulation and an experimental technique developed within BASF AG, i.e. the „miniplant”︁ technique. This article starts by demonstrating the importance of process simulation in the individual phases of process development. It explains the characteristic features of the miniplant technique, what objectives are pursued by employing his technique, and what advantages ccan be achieved, compared with setting up and operating pilot plants. Finally, two examples illustrate that it is possible, by combining process simulation and miniplant technique, to develop processes more rapidely and to scale them up directly from the laboratory to production level.
GVC/DECHEMA‐Ausschüsse „Technische Reaktionsführung”︁ und „Technische Reaktionen”︁
Authors: Schramm Oliver 
Published: May 2005

AbstractAm 4. und 5. März fand im Karman‐Auditorium der RWTH Aachen unter der Leitung von M. BAERNS (Institut für Angewandte Chemie Berlin‐Adlershof e. V.), H. BOCKHORN (Universität Karlsruhe) und B. KOGLIN (BAYER AG, Leverkusen) die diesjährige gemeinsame Sitzung des GVC‐Fachausschusses „Technische Reaktionsführung”︁ und des DECHEMA‐Arbeitsausschusses „Technische Reaktionen”︁ statt. Die 20 Referenten stellten eine breit gefächerte Palette von Forschungsergebnissen vor.
EUROCARBON '98 in Straßburg
Authors: Scharff Peter , Collin G. , Frohs W. , Van Heek K. H. 
Published: May 2005

AbstractDie jährlich stattfindende Internationale Kohlenstoff‐Konferenz wurde in diesem Jahr erstmalig gemeinsam von zwei europäischen nationalen Kohlenstoff‐Gruppen, der französischen GFEC und dem deutschen Arbeitskreis Kohlenstoff (AKK) der DKG, als EUROCARBON '98 vom 5.–9. Juli 1998 in Straßburg veranstaltet. Mit mehr als 500 aktiven Teilnehmern und 70 Begleitpersonen aus 30 Ländern fand die EUROCARBON '98 eine überwältigende Resonanz.
Crystallization and Precipitation: The Optimal Supersaturation
Authors: Mersmann Alfons , Löffelmann Michael 
Published: May 2005

AbstractIn this article optimal supersaturation for cooling and evaporation crystallization are presented. This information is based on a simplified model which describes the metastable zone width of activated nucleation. The model assumes that the nucleation step is very fast and the occurrence of the shower of nuclei which is used to define the metastable zone width is caused by the growth of activated nuclei. In future new sensors for the measurement of supersaturation will help to operate batch crystallizers at the optimal supersaturation during the entire batch time.
Estrogen receptor‐α and ‐β immunoreactive neurons in the brainstem and spinal cord of male and female mice: Relationships to monoaminergic, cholinergic, and spinal projection systems
Authors: VanderHorst Veronique G.J.M. , Gustafsson Jan‐Åke , Ulfhake Brun 
Published: May 2005

AbstractFor many populations of estrogen‐sensitive neurons it remains unknown how they are associated with central nervous system circuitries that mediate estrogen‐induced modulation of behavioral components. With the use of double‐labeling immunohistochemistry and tracing techniques, the relationships of estrogen receptor (ER)‐α‐ and ER‐β‐immunoreactive (IR) neurons in the mouse brainstem and spinal cord to monoaminergic, cholinergic, and spinal projection systems are explored. Similar distributions of ER‐IR neurons were present in females and males, with differences in labeling intensity of ER‐α immunoreactivity among males and estrogen‐, and oil‐treated females. Barrington's nucleus, the ventrolateral medulla, and the nucleus of the solitary tract contained spinal‐projecting ER‐α‐IR neurons, whereas ER‐α‐IR neurons in the periaqueductal gray, parabrachial nucleus, and catecholaminergic A1 cell group received spinal input. Numerous tyrosine hydroxylase (TH)‐IR ER‐α‐IR neurons were present in the ventral periaqueductal gray, nucleus of the solitary tract, A1 cell group, and lumbosacral cord. The dorsal raphe nucleus contained ER‐α‐IR and ER‐β‐IR neurons that colocalized with serotonin (5HT), and the reticulotegmental nucleus contained 5HT‐IR ER‐α‐IR neurons. Fibers IR for vesicular acetylcholine transporter (VAChT), TH, and 5HT were located among ER‐α‐IR neurons in the dorsal horn and spinal autonomic regions. Robust staining for TH and VAChT, but not 5HT, was present among ER‐α‐IR neurons in the lumbosacral lateral collateral pathway. Possible modulatory actions of estrogen on each of these ER‐IR populations are discussed in the context of their specific function, including micturition, sexual behavior, ejaculation, cardiovascular and respiratory control, tactile and nociceptive sensory processing, anti‐nociception, endocrine regulation, and feeding. J. Comp. Neurol. 488:152–179, 2005. © 2005 Wiley‐Liss, Inc.
Nucleus retroambiguus‐spinal pathway in the mouse: Localization, gender differences, and effects of estrogen treatment
Authors: VanderHorst Veronique G.J.M. 
Published: May 2005

AbstractNucleus retroambiguus (NRA)‐motoneuronal projections are species‐specific and serve expiration, Valsalva maneuvers, vocalization, and sexual behavior. In cat and monkey, estrogen induces sprouting of NRA‐spinal axons. This pathway may thus serve as a model to study mechanisms through which estrogen induces neuronal plasticity. In this study, NRA‐spinal projections are described in adult mice by using anterograde and retrograde tracing techniques, with attention to gender, strain (CD‐1 and C57BL/6), and estrogen‐induced changes (in ovariectomized females). Labeled NRA‐spinal neurons at the level of the decussation of the corticospinal tract were most numerous after tracer injections into the thoracic and upper lumbar cord. They were medium‐sized and had axons that descended through the contralateral cord. A group of small neurons was labeled in the NRA immediately rostral to the decussation of the corticospinal tract after cervical and thoracic, but not after lumbar injections. This group projected mainly via an ipsilateral pathway. The main projections from the caudal NRA involved motoneurons in the thoracic and upper‐lumbar cord that supply abdominal wall and cremaster muscles. Pelvic floor motoneurons did not receive substantial input. NRA‐spinal projections, especially those involving the upper lumbar cord, were sexually dimorphic, being more extensive in males than in females. Moreover, they were more distinct in estrogen‐treated females than in control females. Strain differences were not observed. The unique features of the caudal NRA‐spinal pathway in the mouse are discussed in the framework of possible functions of this system, such as mating behavior and related social behaviors, parturition, thermoregulation, and control of balance. J. Comp. Neurol. 488:180–200, 2005. © 2005 Wiley‐Liss, Inc.