Dirac's Claim and the Chemists

In 1929 Paul A. M. Dirac claimed that “the underlying physical laws necessary for the mathematical theory of ... the whole of chemistry are thus completely known, and the difficulty is only that the exact application of these laws leads to equations much too complicated to be soluble.” This sentence of Dirac's is cited frequently by historians and philosophers of chemistry in the context of discussions on the hypothetical reduction of chemistry to physics. But how did chemists themselves react to Dirac's claim? Did they feel threatened by physicists who felt they could do their job better than themselves? Did they feel indifferent, or did they simply not care? Was Dirac's paper often cited by chemists? Why was it cited? In this paper, I provide answers to these questions on the basis of an analysis of citations to Dirac's 1929 paper in the Science Citation Index. RID="*" ID="*"Ana Sim?es teaches history of science at the University of Lisbon. Her research is in the history of quantum chemistry and in the history of the sciences at the European peripheries.     

Die Entdeckung der Mercerisation

During the first half of the nineteenth century the industrialization in England was already advanced. In chemistry the transmission phase from the craftsmanship to science took place. Into this time John Mercer was born. As a self‐educated person he managed the way to a chemist. Especially on account of his numerous inventions he gained recognition. To common knowledge became the dicovery of mercerisation. In it his name is living on.     

线性空间中向量极值问题的鞍点

首先在序线性空间中引入广义次似凸映射 ,建立其择一定理 .然后 ,在这种空间中定义向量 Fritz-John鞍点和向量 Kuhn- Tucker鞍点 ,我们讨论了其二者之间以及向量极值问题的弱有效解与他们的关系 .     

New poly(amide-imide)s syntheses. XVII. Preparation and properties of poly(amide-imide)s derived from 3,3-Bis[4-(4-aminophenoxy)phenyl]phthalimidine and various bis(trimellitimide)s

A series of novel bis(phenoxy)phthalimidine-containing poly(amide-imide)s III were synthesized by the direct polycondensation of 3,3-bis[4-(4-aminophenoxy)phenyl]phthalimidine (BAPP) with various aromatic bis(trimellitimide)s in N-methyl-2-pyrrolidone (NMP) using triphenyl phosphite and pyridine as condensing agents. Poly(amide-imide)s III , having inherent viscosities up to 1.36 dL/g, were obtained in quantitative yields. All resulting polymers showed an amorphous nature and were readily soluble in polar solvents such as NMP and N,N-dimethylacetamide. All the soluble poly(amide-imide)s afforded transparent, flexible, and tough films. The glass transition temperatures of these polymers were in the range of 267–322°C and the 10% weight loss temperatures were above 490°C in nitrogen. Some properties of poly(amide-imide)s III were compared with those of the corresponding isomeric poly(amide-imide)s III′ prepared from 3,3-[4-(4-trimellitimidophenoxy)phenyl]-phthalimidine and various aromatic diamines. © 1996 John Wiley & Sons, Inc.     

Benson 真有效意义下向量优化的最优性条件

对向量值映射引入了Clarke切导数,A djacent切导数及Contingent导数的概念,讨论了它们的性质,并用其建立了束向量优化有效解在Benson真有效意义下的Fritz John及Kunh-Tucker条件。     

Quasidisks and the Noshiro–Warschawski criterion

We show that a domain R ? ? has the property that ?(𝔻) is a quasidisk for all ? for which ?v′(𝔻) ? R if and only if there is a compact K ? ? such that rK ∩ (?\R) ≠ Ø for all r > 0. This constitutes a refinement of the well-known Noshiro–Warschawski univalence criterion.     

A Fritz John Approach to First Order Optimality Conditions for Mathematical Programs with Equilibrium Constraints

Mathematical programs with equilibrium constraints (MPECs) are nonlinear programs which do not satisfy any of the common constraint qualifications. In order to obtain first order optimality conditions, constraint qualifications tailored to MPECs have been developed and researched in the past. This has been done by falling back on technical proofs or results from nonsmooth analysis. In this article, we use a completely different approach and show how the standard Fritz John conditions may be used in order to obtain short and elementary proofs for the most important optimality conditions for MPECs. As a by-product, we obtain a new stationarity concept.     

A new and highly sensitive TLC method to measure hypericin using chemiluminescence

ABSTRACT

Hypericin is a polyphenolic compound belonging to the group of polyphenols and is the active constituents of Hypericum perforatum (Saint John’s wort). We present a new high-performance thin-layer chromatography (HPTLC) method to measure a large number of hypericin extracts using chemiluminescence. On a 10?×?10?cm HPTLC plate (LiChrospher® Merck, 1.05586), more than 40 tracks can be simultaneously quantified using a piezoelectric application system (pipeJet) which can apply 56?nL of a methanolic hypericin extract contactless with high precision. For separation, a solvent mixture of ethyl acetate, water, formic acid, methyl tert-butyl ether, and cyclohexane (180?+?14?+?14?+?80?+?30, v/v) was used. The R_f-value of hypericin is 0.27. The method presented is specific for hypericin and offers a limit of quantification of 690 pg hypericin per band.     

The Riemannian Structure of John and Uniform Domains in ℝ<Superscript>n</Superscript>

Using the theory of pre-ends, we study the boundary and metric properties of John and uniform domains in the Euclidean n-space. We obtain some results on the metric Riemannian structure of these classes of domains. We prove that the family of John domains is closed under the class of homeomorphisms quasi-isometric in the intrinsic Riemannian metric and the family of uniform domains is closed under the class of bi-Lipschitz mappings.Original Russian Text Copyright © 2005 Karmazin A. P.__________Translated from Sibirskii Matematicheskii Zhurnal, Vol. 46, No. 4, pp. 786–804, July–August, 2005.     

拟共形映射和弱John域

作为John域的推广,本文定义了弱John域,并讨论了弱John域与拟圆、弱John域与拟共形 映射之间的关系,得到(1)若(?)。中的Jordan域D和它的外部 均是弱John域,则D 是拟圆;(2)R2中的弱John域是拟共不变的;(3)R2中的有界拟圆必是弱John域．最后构造例子 说明R2中的无界拟圆不一定是弱John域．