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71.
72.
Zusammenfassung Dusch- und Schaumbadepr?parate sowie Haarwaschmittel enthalten als Hauptbestandteile im allgemeinen anionische und nichtionische,
gelegentlich auch noch amphotere Tenside. In der vorliegenden Arbeit wird ein Analysengang beschrieben, der nicht nur die
Auftrennung der Tensidgemische und die Identifizierung und Bestimmung der eingesetzten Tenside behandelt, sondern auch Methoden
für den Nachweis und die Bestimmung von Hilfs- und Zusatzstoffen angibt. Daneben wird versucht, die Analysenm?glichkeiten
von Verbindungen aufzuzeigen, die den Pr?paraten besondere zus?tzliche Eigenschaften neben der prim?r gewünschten Reinigungswirkung
verleihen. Zur Isolierung dieser Substanzen (wie z.B. der Sterine und Konditioniermittel) sind von uns Methoden erarbeitet
worden, die in dieser Arbeit erstmalig mitgeteilt werden.
On the analysis of body and hair shampoos based on synthetic tensides
Summary In general, body and hair shampoos contain as main components anionic and non-ionic, sometimes also amphoteric, detergents. A scheme of analysis is given here which not only deals with the separation of the detergent mixtures and the identification and determination of the surfactants employed but also with methods for the detection and determination of additive and auxiliary compounds. Moreover, the attempt is made to point out analytical methods for the determination of those compounds which impart special qualities to the bath preparations and shampoos besides the primary wanted cleaning effect. Methods for the isolation of these substances (as e.g. sterols and conditioning agents) have been elaborated and are described in this paper for the first time.
相似文献
73.
A therapeutic methodology was developed based on the large X-ray absorption cross-section of gold nanoparticles at high photon energies (>81 keV). Experimental results showed that the amounts of the relaxed circular supercoiled DNA (scDNA) for gold nanoparticle-bound scDNA were more than doubled compared to that for free scDNA under otherwise identical radiation conditions. 相似文献
74.
Hwang SH Wang P Moorefield CN Godínez LA Manríquez J Bustos E Newkome GR 《Chemical communications (Cambridge, England)》2005,(37):4672-4674
A novel family of metallopentacycles was constructed by the facile self-assembly of a bis(terpyridine)-carbazole monomer utilizing terpyridine-metal(II)-terpyridine connectivity; its photophysical properties were investigated. 相似文献
75.
Shvedene NV Borovskaya SV Sviridov VV Ismailova ER Pletnev IV 《Analytical and bioanalytical chemistry》2005,381(2):427-430
Polyvinyl chloride-plasticized membrane ion-selective electrodes (ISE) based on conventional ion-exchangers have been proposed as a cheap universal tool to measure the solubilities of ionic liquids (ILs) in water. They are applicable for ILs with a wide range of solubilities in water, since the linear range of a potentiometric response spans several orders of magnitude. As an example, we have fabricated and tested ISEs for widely used alkylimidazolium ionic liquids. The aqueous solubilities of four typical ILs have been determined at 21 °C: 0.075±0.001 mol l–1 (1-butyl-3-methylimidazolium, BMIm, hexafluorophosphate); 0.018±0.001 mol l–1 (BMIm bis(triflylimide)); 0.054±0.007 mol l–1 (1-butyl-2,3-dimethylimidazolium, BDMIm, hexafluorophosphate); 0.014±0.001 mol l–1 (BDMIm bis(triflylimide)). 相似文献
76.
77.
78.
Zhou W Shultz JW Murphy N Hawkins EM Bernad L Good T Moothart L Frackman S Klaubert DH Bulleit RF Wood KV 《Chemical communications (Cambridge, England)》2006,(44):4620-4622
New highly sensitive latent bioluminescent luciferin substrates were designed and synthesized for monitoring mammalian glutathione S-transferase (GST) and Schistosoma japonicum enzyme activities. 相似文献
79.
Vibrationally highly excited molecules react extremely fast with atoms and probably with radicals. The phenomenon can be utilized for selectively enhancing the rate of reactions of specific bonds. On the basis of quasiclassical trajectory calculations, the paper analyzes mechanistic details of a prototype reaction, H + HF(v). At vibrational quantum numbers v above 2, the reaction exhibits capture-type behavior, that is, the reactive cross section diverges as the relative translational energy of the partners decreases, both for the abstraction and for the exchange channel. The mechanism of the reaction for both channels is different at low and at high translational energy. At low vibrational energy, the reaction is activated, which is switched to capture-type at high excitation. The reason is an attractive potential that acts on the attacking H atom when the HF molecule is stretched. In contrast to the 6-SEC potential surface of Mielke et al., the switch cannot be observed on the Stark-Werner potential surface, due to a small artificial barrier at high H-HF separation, preventing the reactants from obeying the attractive potential and also proving the importance of the latter. The exchange reaction can be observed even when the total energy available for the partners is below the exchange barrier, because at low translational energies the product F atom of a successful abstraction step can re-abstract that H atom from the intermediate product H2 molecule that was originally the attacker. 相似文献
80.
Erika T. Camacho 《Communications in Nonlinear Science & Numerical Simulation》2013,18(11):3086-3097
Through the mathematical study of two models we quantify some of the theories of co-development and co-existence of focused groups in the social sciences. This work attempts to develop the mathematical framework behind the social sciences of community formation. By using well developed theories and concepts from ecology and epidemiology we hope to extend the theoretical framework of organizing and self-organizing social groups and communities, including terrorist groups. The main goal of our work is to gain insight into the role of recruitment and retention in the formation and survival of social organizations. Understanding the underlining mechanisms of the spread of ideologies under competition is a fundamental component of this work. Here contacts between core and non-core individuals extend beyond its physical meaning to include indirect interaction and spread of ideas through phone conversations, emails, media sources and other similar mean. This work focuses on the dynamics of formation of interest groups, either ideological, economical or ecological and thus we explore the questions such as, how do interest groups initiate and co-develop by interacting within a common environment and how do they sustain themselves? Our results show that building and maintaining the core group is essential for the existence and survival of an extreme ideology. Our research also indicates that in the absence of competitive ability (i.e., ability to take from the other core group or share prospective members) the social organization or group that is more committed to its group ideology and manages to strike the right balance between investment in recruitment and retention will prevail. Thus under no cross interaction between two social groups a single trade-off (of these efforts) can support only a single organization. The more efforts that an organization implements to recruit and retain its members the more effective it will be in transmitting the ideology to other vulnerable individuals and thus converting them to believers. 相似文献