There is, I think, something ethereal about i —the square root of minus one. I remember first hearing about it at school. It seemed an odd beast at that time—an intruder hovering on the edge of reality.

Usually familiarity dulls this sense of the bizarre, but in the case of i it was the reverse: over the years the sense of its surreal nature intensified. It seemed that it was impossible to write mathematics that described the real world in …

I and i

THE DESIGN AND ANALYSIS OF EXPERIMENTS. By Oscar Kempthorne. New York, John Wiley and Sons, Inc., 1952. 631 pp. $8.50. This book by a teacher of statistics (as well as a consultant for \"experimenters\") is a comprehensive study of the philosophical background for the statistical design of experiment. It is necessary to have some facility with algebraic notation and manipulation to be able to use the volume intelligently. The problems are presented from the theoretical point of view, without such practical examples as would be helpful for those not acquainted with mathematics. The mathematical justification for the techniques is given. As a somewhat advanced treatment of the design and analysis of experiments, this volume will be interesting and helpful for many who approach statistics theoretically as well as practically. With emphasis on the \"why,\" and with description given broadly, the author relates the subject matter to the general theory of statistics and to the general problem of experimental inference. MARGARET J. ROBERTSON

The Design and Analysis of Experiments

In this review, we highlight the use of organic photoredox catalysts in a myriad of synthetic transformations with a range of applications. This overview is arranged by catalyst class where the photophysics and electrochemical characteristics of each is discussed to underscore the differences and advantages to each type of single electron redox agent. We highlight both net reductive and oxidative as well as redox neutral transformations that can be accomplished using purely organic photoredox-active catalysts. An overview of the basic photophysics and electron transfer theory is presented in order to provide a comprehensive guide for employing this class of catalysts in photoredox manifolds.

Organic Photoredox Catalysis

介绍了Kirk—Othmer Encyclopedia of Chemical Technology（化工技术百科全书）（第五版）电子图书网络版数据库，并对该数据库使用方法和检索途径作出了说明，且结合实例简单地介绍了该数据库的检索方法。

Kirk-Othmer Encyclopedia of Chemical Technology数据库介绍及实例

A flow-focusing geometry is integrated into a microfluidic device and used to study drop formation in liquid–liquid systems. A phase diagram illustrating the drop size as a function of flow rates and flow rate ratios of the two liquids includes one regime where drop size is comparable to orifice width and a second regime where drop size is dictated by the diameter of a thin “focused” thread, so drops much smaller than the orifice are formed. Both monodisperse and polydisperse emulsions can be produced.

/pdf/formation-of-dispersions-using-flow-focusing-in-2zw2hx9w2y.pdf

Formation of dispersions using “flow focusing” in microchannels

Direct fluorination of aromatics with elemental fluorine in microstructured reactors

Tailor-made microdevices for maximizing process intensification and productivity through advanced heating

The pre-Socratic philosophers made the first honest attempt, at least in the western world, to describe natural phenomena in a rudimentary scientific manner and to exploit those for technological application [1]. Pythagoras of Samos (570–495 BC) was an Ionian Greek philosopher and the first to actually call himself a “philosopher”. He was credited with many mathematical and scientific discoveries, including the Pythagorean theorem, Pythagorean tuning, the five regular solids, the theory of proportions, and the sphericity of the Earth. The Pythagorean triple is also well-known. Heraclitus of Ephesus (535–475 BC) was famous for his insistence on ever-present change as the fundamental essence of the universe, as stated in the famous saying “panta rhei” —everything flows.

Everything Flows: Continuous Micro-Flow for Pharmaceutical Production

Es wird ein Verfahren zum Mischen mindestens zweier Fluide beschrieben, bei dem eine Vielzahl getrennter Fluidstrome der beiden Fluide unter Bildung abwechselnd benachbarter Fluidlamellen zusammengefuhrt werden. Die vereinigten Fluidlamellen werden unter Ausbildung eines fokussierten Gesamtfluidstroms abgefuhrt. Der fokussierte Gesamtfluidstrom wird als Fluidstrahl in eine Wirbelkammer unter Ausbildung einer nach innen stromenden Fluidspirale eingeleitet. Das Ableiten der gebildeten Mischung erfolgt aus dem Zentrum der Fluidspirale. Der Mikrovermischer ist gekennzeichnet durch eine Wirbelkammer (6, 16, 116), in die der Fokussierungskanal (5, 15, 35, 45, 105, 105', 115, 115') derart einmundet, dass der fokussierte Gesamtfluidstrom als Fluidstrahl eintritt unter Ausbildung einer nach innen stromenden Fluidspirale (10). Mindestens ein mit der Wirbelkammer (6, 16, 116) fluidisch in Verbindung stehender Auslasskanal (7) dient zum Ableiten der bebildeten Mischung.

Volker Hessel

Papers

Direct fluorination of aromatics with elemental fluorine in microstructured reactors

Tailor-made microdevices for maximizing process intensification and productivity through advanced heating

Everything Flows: Continuous Micro-Flow for Pharmaceutical Production

Verfahren und statischer Mischer zum Mischen mindestens zweier Fluide

Numbering up von Mikroreaktoren: Ein neues Flüssigkeitsverteilsystem