制造可冲散产品——化圆为方

过去几十年中,湿巾市场总体上快速增长.预计2018-2023年,个人护理湿巾销售额复合年均增长率为7.9％,按非织造布用量计的复合年均增长率为8.0％. 在个人护理湿巾中,湿厕纸是近年来快速发展的产品类别.湿厕纸主要采用气流成网、水刺、湿法水刺非织造布为基材,其中以湿法水刺为主流.     

Solubilization of fish muscle proteins with buffers containing sodium dodecyl sulfate

Summary The extraction of fish muscle protein using SDS containing solubilization buffers was studied varying the time and the temperature of solubilization, as well as pH and SDS concentration of the buffer. At pH < 6 the myofbrillar proteins were incompletely solubilized; temperatures of 80-100 °C resulted in protein degradation observable in the SDS-PAGE.Samples of fish muscle containing high amounts of formaldehyde (50 mmoles FA/kg wet weight) could only be solubilised at 100 °C; on the other hand it was possible to solubilize cooked and/or canned products under mild conditions (2% SDS, 1% 2-ME, pH 8.9, shaking for 2 h at 60 °C).

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Solubilisierung von Fischmuskelproteinen durch Natriumdodecylsulfathaltige Puffer

Zusammenfassung Der Einfluß von Solubilisierungszeit und -temperatur, des pH-Wertes und der SDS-Konzentration des Solubilisierungspuffers auf die Extraktion von Fischmuskelproteinen wurde überprüft. Bei pH-Werten < 6 wurden die myofbrillären Proteine nur unvollständig gelöst; Solubilisierungstemperaturen von 80 bis 100 °C führten zu einem in der SDS-PAGE sichtbaren Proteinabbau. Fischmuskelproben mit hohem Formaldehydgehalt (50 mmole FA/kg Feuchtgewicht) ließen sich nur bei 100 °C vollständig solubilisieren; demgegenüber gelang die weitgehende Solubilisierung gegarter und/oder sterilisierter Produkte unter milden Bedingungen (2% SDS, 1% 2-ME, pH 8,9; 2stündiges Schütteln bei 60 °C).

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Abbreviations FA formaldehyde - IEF isoelectric focusing - 2-ME 2-mercaptoethanol - PA polyacrylamide - PAGE polyacrylamide gel electrophoresis - pI isoelectric point - SDS sodium dodecyl sulfate - TMAO trimethylamine oxide - Tris Tris (hydroxymethyl)methylamine     

Einsatz von mathematischer Simulation und Miniplant-Technik in der Verfahrensentwicklung

Use of mathematical simulation and miniplant techniques in process development . An integrated study of synthesis and workup or of entire processes is often required in the development of chemical processes. This leads to a large number of possible solutions, of which the most economic one must be selected. This variety can only be mastered at reasonable expense with the aid of present-day techniques. Examples are presented to show how just a few economic possibilities can be selected and optimized from the plethora of alternatives in simulation calculations based on just a few properties of the materials involved. Economics is the basis of all evaluation. Use of miniplants is considered in the second part of the article, and costs and time-expenditure are compared with those for industrial pilot plants. Planning and evaluation of experiments raise the effectiveness of this empirical work. Problems of scale-up are considered, and the advantages of physico-chemically sound scale-up models are demonstrated.     

Weld corrosion in urea synthesis

Corrosion of 316L stainless welds in urea synthesis systems is not due to preferential attack of ferrite, but to dissolution of sigma phase formed from ferrite by successive weld passes. Proper element balancing of 316L filler metal, or welding with Alloy 20 or a high nitrogen 316 weld eliminates this problem.     

Prozeßsystemtechnik — Gedanken zu Notwendigkeit und Inhalt einer akademischen Lehre

Process System Engineering. Thoughts on the need for and curriculum of an academic course of instruction . The raw material, energy, and environmental situation, international competition, and the decline in product innovation are increasingly casting doubts on conventional processes and their realization. Hence, in the future-training of chemical engineers a reasonable amount of time should be devoted to the study of system facets, i. e. to thinking and acting in complex systems of interrelationships. Under the general leading ?Process System Engineering”? those activities are discussed which are relevant to the design and planning of chemical engineering systems (process synthesis) and the mathematical analysis of a given system (process analysis). Process synthesis is the creative facet of project planning involving several methodologies. Process analysis embraces steady-state and non-steady state mass- and energy-balancing and the mathematical evaluation of various process alternatives on the basis of operating costs and investment as well as the simulation of operational behaviour and optimization of process configurations using mathematical models. The following article discusses a selection of points which should play an important part in the teaching of process synthesis and process analysis and considers some examples by way of illustration.