bluuebunny/crossref_metadata_2025 huggingface dataset:
Die Eigenschaften der Salze primärer unverzweigter Alkylsulfate und ihrer Lösungen im Hinblick auf ihren technischen Einsatz, 1. Teil
Authors: Götte E.
Published: November 2006

Überblick über die Eigenschaften der primären unverzweigten Alkylsulfate, die durch exakte physikalische Messungen und durch konventionelle Methoden bestimmt werden können: Kristallform, Löslichkeit, Lösungszustände; Anreicherung an Grenzflächen mit Bezug auf die Oberflächen‐ und Grenzflächenspannung; Oberflächenkonzentration in Grenzflächen, Adsorption an Textilfasern und anderen festen Oberflächen; kritische Konzentration der Mizellbildung, Methoden zu deren Messung, Zahlenwerte für reine Homologen und ihre Gemische und ihre Änderungen bei Elektrolyt‐Zusätzen; Aufbau der Mizellen; Solubilisationsvorgänge und Wechselwirkungen zwischen den Alkylsulfaten und Eiweißstoffen. Ergebnisse konventioneller Benetzungs‐, Wasch‐ und Schaumteste.
Para‐Diamine in Haar‐Färbemitteln
Authors: Heilingötter R.
Published: November 2006

Die Toxizität von p‐Phenylendiamin‐Haarfarben ist stärker als die von p‐Toluylendiamin enthaltenden, doch ist das Färbevermögen der letzteren geringer. Durch besondere Zusätze ist es aber möglich, den Nachteil von p‐Toluylendiamin aufzuheben. Die Fortschritte in der Technik der Herstellung von Haarfarben tragen dazu bei, deren Verträglichkeit weiter zu steigern.
Chemie und Parfümerie: Beitrag zur Verwendung von isomeren Ironen in der Parfümerie
Authors: Naves Y.‐R.
Published: November 2006

Der Verfasser beweist, daß die Klassifizierung von Substanzen als synthetische Parfums nicht von einer persönlichen Bewertung abhängen sollte, die immer nur in der Form eines diskutablen Wertes ausgedrückt werden kann, sondern von einer Statistik, die Gruppen qualifizierter Beobachter in ihren Experimenten gefunden haben. Er zeigt, daß der Wert eines synthetischen Parfums das Ergebnis der notwendigen Zusammenarbeit des Chemikers, Parfumeurs und Verkäufers ist. Diese Darlegungen werden durch das Studium der Ironen‐Isomeren und ihrer Anwendungsmöglichkeiten erläutert.
Ölbestimmung von Raps durch Extraktionsanalyse I: Zerkleinerung im Mörser
Authors: Troëng S.
Published: November 2006

Eine neue Methode der Ölbestimmung wurde entwickelt, die besser reproduzierbare Resultate liefert als die offizielle schwedische Methode. Der einzige Nachteil ist, daß die Proben mit der Hand im Mörser zerkleinert werden müssen.
Über die Qualität japanischer Seifen
Authors: Ueno S.
Published: November 2006

Vf. hat seit 1937 eine große Zahl japan. Seifen analysiert und gibt Durchschnittswerte der Seifenzusammenstellung der Jahre 1937, 1944, 1946 und 1952 sowie eine Statistik der Seifenproduktion in Japan von 1926 bis 1952.
Über ein Schnellverfahren zur Wasserbestimmung in Emulsionen sowie in salben‐ und pastenförmigen oder sehr zähflüssigen Stoffgemischen mit Hilfe eines einfachen Vakuum‐Trockengerätes und dem Planwägeglas
Authors: Purr A.
Published: November 2006

Es wird zunächst ein neu entwickeltes Vakuum‐Trockengerät besprochen und die damit eingehaltene Arbeitsweise näher beschrieben. Die Versuchsergebnisse zeigen sowohl untereinander als auch im Vergleich mit den nach den konventionellen Methoden erhaltenen Werten eine befriedigende Übereinstimmung und sind unabhängig von Einflüssen der relativen Feuchtigkeit und unbeeinflußt von sekundären Umsetzungen. Abschließend wird auf die Anwendungsmöglichkeiten dieses Trockengerätes näher eingegangen.
Über die Beziehungen zwischen der Konstitution und den Eigenschaften von Alkylbenzolsulfonaten mit jeweils einer geraden oder verzweigten Alkylkette bis zu 18 Kohlenstoff‐Atomen I
Authors: Grieß W.
Published: November 2006

Technisch wichtige Eigenschaften definierter, reiner Alkylsulfonate und einiger binärer Gemische wurden eingehend untersucht: Kritische Micellbildungskonzentration, Erniedrigung der Oberflächenspannung, Benetzungs‐, Schaum‐ und Waschvermögen. Die erhaltenen Ergebnisse werden ausführlich diskutiert.
Zur Frage des Wirkungsmechanismus von Natrium‐Carboxymethylcellulose in Waschflotten: Die Adsorption von Netzmitteln an festen Stoffen in Gegenwart von Na‐CMC
Authors: Krämer S. H. , Hoepfner P.
Published: November 2006

Mit Hilfe der Oberflächenspannung wird die Adsorption von Netzmitteln an Baumwollgewebe und festen Partikeln in Suspensionen untersucht und gefunden, daß eine Beeinflussung der Adsorption oder Verdrängung des Netzmittels durch Natrium‐Carboxymethylcellulose (Na‐CMC) im allgemeinen nicht eintritt.
Chemisch‐technische Rundschau Neuzeitliche Technologie der Fette und Fettprodukte XIV: Der Transport der Rohstoffe
Authors: Kaufmann H. P. , Thieme J. G.
Published: November 2006

Die überaus zahlreichen Anfragen nach Sonderdrucken der laufenden Aufsatzreihe, „Neuzeitliche Technologie der Fette und Fettprodukte”︁ veranlaßten mich, eine größere Anzahl anfertigen zu lassen, um sie gesammelt abgeben zu können. Da die landwirtschaftliche und industrielle Erzeugung von Nahrungsfetten und technischen Erzeugnissen, einschließlich ihrer Austauschstoffe, die Zuliefer‐Industrien und alle mit dem Gesamtgebiet zusammenhängenden technologischen Fragen, z. B. Verfahrenstechnik, Fabrikbau, Energie‐Versorgung, Wasserwirtschaft usw., berücksichtigt werden sollen, dürfte das Erscheinen der Aufsätze noch geraume Zeit in Anspruch nehmen. Deshalb soll jeweils eine Anzahl von Veröffentlichungen in Einzellieferungen zusammengefaßt werden. Auf diese Weise wird die in ihrer Vollständigkeit einzigartige Sammlung in beschränkter Zahl preiswert zur Verfügung gestellt werden können. Bei der Subskription sollen Abonnenten dieser Zeitschrift sowie Mitglieder der DGF und IGF in jeder Weise bevorzugt behandelt werden.
Über die Adsorptionstrennung von Wachsen und Paraffin‐Oxydationsprodukten III
Authors: Spengler G. , Hauf G.
Published: November 2006

Die Kontrolle der adsorptiven Zerlegung von Wachsen und Wachsgemischen wird mit Hilfe der Refraktometer‐Methode durchgeführt, indem der Brechungsindex des Eluates laufend verfolgt wird. Die Grundlagen für die quantitative Auswertung der Refraktionskurven wurden erarbeitet.
In verdorbenen Heringspräserven vorkommende Bakterien‐Arten und ihr Verhalten gegenüber Salz und Konservierungsmitteln
Authors: Nikkilä O. E.
Published: November 2006

Die Kultur‐Eigenschaften von 19 aus verschiedenen Typen verdorbener Heringspräserven isolierten Stämmen wurden untersucht. Sie haben einen großen Bereich der Salz‐Toleranz, was teilweise durch Anpassung während längerer Lagerung erklärt werden kann. Die Reihenfolge der Wirksamkeit verschiedener Konservierungsmittel bei pH 5.5 und 7.0 und bei verschiedenen Salz‐Konzentrationen wird angegeben.
Zur Ölbedarfsfrage von Ruß
Authors: Eberle G.
Published: November 2006

Nach Diskussion der verschiedenen Methoden zur Bestimmung des Ölbedarfs von Ruß wird eine Arbeitsvorschrift gegeben, die exakte Werte ergibt.
Eine einfache Nachweismethode für Paraffin in Wachsgemischen, II. Mitt
Authors: Hessler W.
Published: November 2006

Unter besonders zu beachtenden Versuchsbedingungen hat die früher beschriebene Methode Gültigkeit in allen Fällen.
Papier‐Chromatographie der Sterine
Authors: De Zotti G. , Capella P. , Jacini G.
Published: November 2006

Für einige Sterine und deren Derivate werden die Verteilungskoeffizienten und die Rf‐Werte in verschiedenen Systemen bestimmt, ferner wird für jedes System der Quotient aus den Querschnittsvolumina der mobilen und der stationären Phase ermittelt. Die für die Trennung von freien Sterinen und von Sterin‐Derivaten geeigneten Arbeitsbedingungen werden erprobt und für die Trennung von Sterinen einiger Pflanzenöle angewendet. Eine ausführliche Beschreibung der durchgeführten Versuche wird gegeben.
Die Entwicklung von Aerosol‐Lacken
Authors: Hoffmann B.
Published: November 2006

Lack‐Aerosole gewinnen zunehmend an Interesse. Die für derartige Produkte verwendeten Lacke (die Aerosol‐Lacke) müssen insbesondere hinsichtlich ihrer Mischbarkeit gut auf die verwendeten Frigen‐Sicherheitstreibgase abgestimmt werden. Es werden Hinweise zur Entwicklung solcher Lacke gegeben und Einzelheiten aus der Laboratoriumspraxis mitgeteilt.
Die Dünnschicht‐Chromatographie auf dem Fettgebiet II: Trennung der Cholesterin‐Fettsäureester
Authors: Kaufmann C. H. P. , Makus Z. , Deicke Apotheker F.
Published: November 2006

Cholesterinester von 15 gesättigten und ungesättigten Fettsäuren wurden rein dargestellt und mit Hilfe der Dünnschicht‐Chromatographie untersucht. Die Ester kurzkettiger und ungesättigter Fettsäuren lassen sich auf nicht imprägnierten Kieselgel‐Platten trennen, auf mit Paraffin hydrophobierten Platten bei zweidimensionaler Arbeitsweise auch Gemische derselben mit den Estern langkettiger Fettsäuren.
Chemische Untersuchung des Samenfettes von indischen Cheiranthus Cheiri
Authors: Rahman A. , Khan M. Sami
Published: November 2006

Das Samenöl von Cheiranthus Cheiri Linn, einer indischen Crucifere, wird als „Todri”︁ bezeichnet. Die Untersuchung von “Red‐Todri” und “Yellow‐Todri” mit Hilfe der Ester‐Fraktionierung für feste Fettsäuren, Bromierung und rhodanometrischen Methoden für flüssige zeigt, daß die Zusammensetzungen dieser Öle von denen der bei anderen Cruciferen‐Sorten üblichen abweicht.
Dünnschicht‐Chromatographie auf dem Fettgebiet IV: Trennung der Triglyceride
Authors: Kaufmann H. P. , Makus Z. , Das B.
Published: November 2006

Es wird über die dünnschichtchromatographische Trennung von Triglyceriden berichtet. Vff. trennen 20 synthetische sowie zahlreiche natürliche Triglycerid‐Gemische auf Kieselgur‐Platten, die mit Kohlenwasserstoffen bzw. Siliconölen imprägniert wurden. Es werden verschiedene chromatographische Systeme angewendet.
Die Dünnschicht‐Chromatographie auf dem Fettgebiet VII: Trennung von Fettsäuren und Triglyceriden auf Gips‐Schichten
Authors: Kaufmann H. P. , Khoe T. H.
Published: November 2006

Es wird über die Herstellung von auswaschbaren dünnschichtchromatographischen Platten aus Gips berichtet. Durch Anwendung dieser Gipsschicht‐Platten ist es möglich, chemische Reaktionen bzw. Anfärbungen der pc‐Methoden, die ein Auswaschen des Überschusses der Reagentien erfordern, auf die dünnschichtchromatographische Technik zu übertragen und dadurch spezifische Nachweisreaktionen zu erzielen. Hydrierungs‐ und Bromierungs‐Reaktionen, mit deren Hilfe kritische Paare von Fettsäuren getrennt werden konnten, werden beschrieben.
Untersuchungen über die Fähigkeit der Spreitung von Lipoiden und der Permeation von Wasserdampf durch die lebende Haut
Authors: Neuwald F. , Fetting K. E. , Szakall A.
Published: November 2006

Die Untersuchungen mit zehn verschiedenen Lipoiden, deren Viskosität und Grenzflächenspannung gegenüber Wasser bei der Hauttemperatur experimentell bestimmt wurden, zeigen, daß ihre Spreitfähigkeit sowohl von der chemischen Zusammensetzung der Lipoide als auch ihren physikalischen Eigenschaften abhängig ist. Die Prüfungen der untersuchten Fettstoffe im Hinblick auf ihren Einfluß auf die Wasserabgabe durch die Haut ergaben, daß eine direkte Beziehung zwischen der Spreitfähigkeit und der Perspiratio insensibiles besteht: Je besser ein Lipoid spreitet, desto geringer ist die Hemmwirkung.
Verhalten eines Waschmittels mit verschiedenen Phosphaten und Phosphat‐Mengen bei Wasserhärten von 10 bis 35° dH
Authors: Oldenroth O.
Published: November 2006

Das Kalkbindevermögen in Abhängigkeit von der Reaktionstemperatur, die Waschkraft und die Entwicklung der Bleichintensität werden untersucht.
Copolymerisationen auf dem Anstrichmittel‐Gebiet IV: Die Reaktion trocknender Öle mit Phenylacetylen
Authors: Kaufmann H. P. , Brüning H.
Published: November 2006

Phenylacetylen als dienophiler Partner liefert mit trocknenden Ölen — bei Isolenölen nach thermischer Konjugierung derselben — Addukte, die gute lacktechnische Eigenschaften aufweisen.
Zusammenhänge zwischen Deckvermögen weiß‐pigmentierter Anstriche, Augenschwellenwert und Untergrund
Authors: Hademar H.
Published: November 2006

In der Praxis werden häufig die nach dem DIN‐Entwurf ermittelten Deckvermögenswerte für zu hoch gehalten. Vf. untersuchte die Einflüsse der Augenschwelle und des Untergrundes auf den Deckvermögenswert und stellte fest, daß ein kleinerer Augenschwellenwert ebenso wie ein sehr heller weißer Untergrund das Deckvermögen erniedrigt, und ein grauer anstelle des schwarzen Untergrundes des Deckvermögen erhöht. Bei der praktischen Herstellung von Lackierungen und Anstrichen liegen sehr oft graue Untergründe vor. Andererseits wurde in den durchgeführten Versuchen der Augenschwellenwert niedriger gefunden als ihn der DIN‐Entwurf benutzt. Diese beiden Effekte sind gegenläufig, so daß tatsächlich ein Wert resultieren kann, der dem nach DIN erhaltenen etwa entspricht.
Bestimmung von Sauerstoff und Stickstoff sowie Erfassung primärer Oxydationsprodukte in Ölen, Fetten und Emulsionen auf physikalisch‐chemischem Wege I: Methodik
Authors: Becker E. , Niederstebruch A.
Published: November 2006

Es wird über eine Verdrängungsmethode zur Bestimmung von Sauerstoff und Stickstoff in Ölen, Fetten und Emulsionen berichtet. Sie dient zugleich zur Eichung der Sauerstoffbestimmungsverfahren nach Tödt und nach Clark, die beschrieben werden. Mit Hilfe der Clark'schen Zelle wurde ein Verfahren entwickelt, das den Sauerstoffgehalt in Ölen, Fetten und Emulsionen kontinuierlich und registrierend zu messen erlaubt. Zur quantitativen Bestimmung der Fetthydroperoxyde wird ein polarographisches Meßverfahren erläutert. In einem Autoxydationsversuch wird gezeigt, daß der umgesetzte Sauerstoff weitgehend zur Hydroperoxydbildung herangezogen wird.
Studien über die Vergilbung und Vergrauung von verschiedenen Faserstoffen
Authors: Oldenroth O.
Published: November 2006

Zur Feststellung einer möglichen WAS‐Sorption wurden Gewebe aus Baumwoll‐, Reyon‐, Polyamid‐ und Polyester‐Fasern wiederholt unter verschiedenen Bedingungen gewaschen und anschließend mit Benzol‐Methanol extrahiert. In einer weiteren Versuchsreihe wurden die gewaschenen Proben bis zu 300 Std. bei 60° C gelagert. Durch die Lagerungseinflüsse bedingt, traten weitgehende Weißgradveränderungen ein. Waschbehandlungen unter Mitverwendung von Ruß ließen an den verschiedenartigen Faserstoffen durch stattfindende Rußsorption auffällig unterschiedliche Vergrauungstendenzen eintreten.
Über den Effekt der Einarbeitung von Diolen in Alkydharze auf Basis verzweigter Carbonsäuren
Authors: Vegter G. C. , Oosterhof H. A.
Published: November 2006

Bei der Modifizierung von Alkydharzen auf Basis verzweigter Carbonsäuren mit Diolen werden die verschiedenen Eigenschaften der Harze stark beeinflußt. Nicht nur die Länge sondern auch die Struktur der Kette zwischen zwei Hydroxylgruppen des Diols üben auf die mechanischen Eigenschaften des Lackfilms einen erheblichen Einfluß aus. Außerdem ist die Struktur dieser Kette auch für die chemische Beständigkeit wichtig. Der Einfluß der Diolstruktur auf die mechanischen Eigenschaften der ausgehärteten Lackfilme ist teils auf eine größere Flexibilität des vernetzten Systems, teils auf eine bessere weichmachende Wirkung des nichtgebundenen Teils des Alkyds zurückzuführen.
Fabrication of Thermo‐Responsive Hybrid Hydrogels by In‐Situ Mineralization and Self‐Assembly of Microgel Particles
Authors: Wehnert Franziska , Pich Andrij
Published: November 2006

Summary: An in‐situ mineralization process in the presence of thermo‐responsive microgels leads to the formation of well‐defined hybrid materials. Experimental data suggest that control of the mineralization process in the presence of the microgels offers the possibility to obtain sub‐micrometer‐sized hybrid particles or macroscopic hybrid hydrogels. The rapid formation of CaCO3 crystals in the microgel structure favors the preparation of the hybrid particles wherein inorganic crystals cover the shell layer of the microgel. The slow formation of CaCO3 crystals leads to the simultaneous self‐assembly of the microgel particles on the bottom of the reaction vessel, and the formation of a physical network. It has been demonstrated that hybrid hydrogel materials with different calcium carbonate contents and temperature‐dependent swelling‐deswelling properties can be prepared.

Formation of a hybrid hydrogel by the vapor diffusion method.

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Formation of a hybrid hydrogel by the vapor diffusion method.
Morphological Transformation and Photophysical Properties of Rod‐Coil Poly[2,7‐(9,9‐dihexylfluorene)]‐block‐poly(acrylic acid) in Solution
Authors: Tung Yi‐Chih , Wu Wen‐Chung , Chen Wen‐Chang
Published: November 2006

Summary: The synthesis, morphology, and photophysical properties of PF‐b‐PAA with different coil lengths in dilute solutions of dichloromethane/methanol are reported. A tape‐like lamellar morphology is observed at a short coil length of PF‐b‐PAA. As the coil length increases, a large compound micelle, sphere, or vesicle is observed with different methanol contents because of the enhancement of the PAA swelling with methanol and the interfacial tension between the PF core and the PAA corona. Upon further increase of the coil length, an inverted morphology of a sphere or rod with a PF corona and PAA core is first observed but the core/corona is then reversed at a high methanol content as a result of the enhanced solubility of PAA. The morphological transformation leads to a significant variation in optical absorption or fluorescence characteristics because of the possible H‐aggregate formation.

Some of the various morphologies observed upon varying the coil length and the selective solvent content.

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Some of the various morphologies observed upon varying the coil length and the selective solvent content.
Transcranial brain sonography findings in clinical subgroups of idiopathic Parkinson's disease
Authors: Walter Uwe , Dressler Dirk , Wolters Alexander , Wittstock Matthias , Benecke Reiner
Published: November 2006

To investigate whether transcranial brain sonography (TCS) discriminates different courses of idiopathic Parkinson's disease (PD), 101 patients with clinically definite PD were studied. In four patients, TCS was not possible due to insufficient acoustic temporal bone windows. Substantia nigra (SN) hyperechogenicity was found in 96% of assessable patients. Larger SN echogenic size correlated with younger age at PD onset (Spearman correlation, r = −0.383;P< 0.001), but not with age, PD duration, or severity. Marked bilateral SN hyperechogenicity indicated early‐onset rather than late‐onset PD, and akinetic–rigid (AR) or mixed‐type (MX) PD rather than tremor‐dominant PD. SN echogenic sizes were larger contralateral to the clinically more affected side in AR PD and MX PD patients. Reduced echogenicity of brainstem raphe was associated with depression (RR = 1.61; 95% CI = 1.05–2.46;P= 0.044) but not with other clinical features. Caudate nucleus hyperechogenicity was, independently from PD duration, related to drug‐induced psychosis (RR = 2.40; CI = 1.36–4.22;P= 0.001), but not to motor fluctuations. Lenticular nucleus hyperechogenicity indicated AR PD rather than tremor‐dominant PD (RR = 1.44; CI = 1.11–1.86;P= 0.040). Frontal horn dilatation > 15.4 mm (mean of bilateral measurements) indicated increased risk of dementia (RR = 4.11; CI = 1.51–11.2;P= 0.001). We conclude that TCS displays characteristic changes of deep brain structures in different clinical manifestations of PD. © 2006 Movement Disorder Society
Ring‐opening polymerization of ϵ‐caprolactone initiated with different ruthenium derivatives: Kinetics and mechanism studies
Authors: Mata‐Mata José Luis , Gutiérrez J. Alfredo , Paz‐Sandoval M. Angeles , Madrigal Amira R. , Martínez‐Richa Antonio
Published: November 2006

End‐functionalized polyesters have been synthesized by ring‐opening polymerization (ROP) of ϵ‐caprolactone (CL) initiated with five different ruthenium derivatives in the presence of a series of alcohols as transfer agents. Mechanistic studies were performed for ROP of CL with RuCl2(PPh3)3 (I), TpRuCl(PPh3)2 (II), and TpRuCl(PHPh2)(PPh3) (III) as catalysts in the presence or absence of benzyl alcohol (BzOH). Obtained molecular weights are proportional to CL/BzOH ratio, but there is not a direct relationship with CL/ruthenium complex ratios. 1H and 13C NMR spectroscopy revealed the existence of benzyl ester end‐groups. Catalysis involves (a) dissociation of ruthenium complexes, (b) coordination of the lactone CL, (c) coordination of the BzOH with the formation of a metal alkoxide, (d) transfer from the alkoxyl ligand to the coordinated lactone, and (e) ring‐opening of CL by oxygen‐acyl bond cleavage. The proposed mechanism is supported by 1H, 13C, and 31P NMR, gel permeation chromatography (GPC), and MALDI‐TOF analysis of the polymers. © 2006 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 44: 6926–6942, 2006
Influence of herbicides on photosynthetic activity and transpiration rate of intact plants
Authors: van Oorschot J. L. P.
Published: November 2006

The effect of various herbicides on photosynthesis, respiration and transpiration of intact plants has been studied in a routine assembly. Simultaneous measurements were made under different experimental conditions in four small plant chambers, in which the shoots of various plant species can be accommodated.

The herbicide is applied during measurement, so that the effect can be related to the photosynthetic activity of the same plants before treatment.

The selectivity of various herbicides was studied by determining the capacity of a plant species to inactivate a herbicide absorbed by the roots. These and other differential effects of various herbicides on photosynthetic activity of different plant species coincide with the selective properties in the field. Such differences are also observed after leaf sprayings. The duration of the experiments is kept short.

Bean plants were studied under various experimental conditions of air humidity, light intensity and temperature resulting in different transpiration rates. The decrease in photosynthetic activity owing to the presence of a herbicide in the nutrient solution at a standard concentration was more rapid at the higher transpiration rates. The total transpiration during treatment up to 50% inhibition of photosynthesis was constant under the various experimental conditions.

Specific inhibitors of the photosynthetic process had a more pronounced effect on the photosynthetic activity than on transpiration rate. Some other herbicides affect transpiration as well as photosynthesis.
Chemical structure and physical properties of candidate insecticides in relation to residual toxicity to adult mosquitos
Authors: Barlow F. , Hadaway A. B.
Published: November 2006

Data are presented on changes in physical properties and insecticidal activity resulting from modifications in chemical structure in two groups of compounds. The first group consists of propoxur and three closely related N‐methylcarbamates and the corresponding N‐acetyl compounds The parent compounds are all highly toxic to adult mosquitos by topical application in solution and deposits from water‐dispersible powder formulations on plywood and plaster of Paris panels have long residual activity. N‐acetylation is not accompanied by excessive loss of toxicity to mosquitos, but increases volatility to the extent that none of the four N‐acetyl derivatives can be considered as potential residual insecticides. The second group consists of tetrachlorvinphos and related vinyl phosphates and vinyl phosphorothionates which show a wide range of toxicity both to adult mosquitos and to mammals.
Structural aspects of penetration through insect cuticles
Authors: Noble‐Nesbitt J.
Published: November 2006

The structure, formation and physico‐chemical properties of insect cuticles are reviewed and the physiology of penetration through the cuticle is discussed.
Mechanisms of action and structure activity relations of herbicides that inhibit photosynthesis
Authors: Büchel K. H.
Published: November 2006

A survey and chemical classification are given for the most important herbicidal inhibitors of photosynthesis. The photochemical reactions involved in photosynthesis are reviewed. The herbicides discussed here all interfere with photosynthetic electron transport in the light reactions. Comments are made on the redox catalysts and the electron transport chain. The mode of action of the herbicides due to inhibition of the light reactions I and II or of photophosphorylation are described. Structure activity correlations according to the regression analysis (Hansch‐approach) are discussed with examples in the classes of acetanilides, benzimidazoles and triazinones. The correlation studies in the series of the Hill‐reaction inhibitors have led to a model for the essential structural elements. Some work on the problem of selectivity and its importance is reviewed.
Inhibitors of shikimate dehydrogenase as potential herbicides
Authors: Baillie A. C. , Corbett J. R. , Dowsett J. R. , McCloskey P.
Published: November 2006

Shikimate dehydrogenase (E.C. 1.1.1.25) is found in plants but not in animals and is therefore an attractive target for a new herbicide. A series of 1,6‐dihydroxy‐2‐oxoisonicotinic acid derivatives was prepared and shown to inhibit the enzyme reversibly. Weak active‐site directed irreversible inhibitors based on these compounds were also synthesised but none was herbicidal.
The effects of small applications of an organophosphorus poison, fenthion on the weaver‐bird Quelea quelea
Authors: Pope G. G. , Ward P.
Published: November 2006

Experiments were carried out in East Africa to determine the effects of single‐drop applications of the avicide Queletox (active ingredient fenthion) on the Red‐billed Quelea Q. quelea, an important agricultural pest.

Birds treated with relatively large amounts of Queletox died within a few hours, as expected. Most of those receiving the smallest lethal doses died 12 to 48 h after treatment. From their terminal fat and muscle condition it was concluded that they died of starvation, despite their apparently healthy appearance following treatment and the easy availability of suitable food.

LD50's of 80 and 220 mg/kg were obtained for Queletox applied to the feathers of the back in drops of varying sizes or concentrations, the amount of solvent having an important effect on the toxicity.

The possibility is raised of reducing the amounts of Queletox used in control operations against the birds, making them safer and cheaper.
The application of granular pesticides
Authors: Nation H. J.
Published: November 2006

Three basic processes are involved in the application of granular pesticides—metering, transporting and distributing. Metering may be simply dependent upon flow through an orifice under gravity but preferably force‐feed mechanisms, usually driven in relation to forward speed are used. Transport may be effected merely under gravity, but pneumatics is also an accepted method particularly for large swath widths. Kinetic energy is also an agency in transporting granules as in “throwing” type distributors and this also achieves the distribution element. With gravity and pneumatic transport the final distribution is usually by spreaders or by nozzles at each outlet.

Assessment of performance is rendered difficult by the very small size of the particles to be detected and the very low rates of application usually employed. Data are required on the appropriate sampling areas which should be used in assessing uniformity of distribution and the significance of the variations measured.

Cooperation between all the disciplines of workers in the field is necessary for further development of the technique and in particular in the field of formulation a valuable contribution would be in the reduction in the diversity of physical properties of all the granular materials in use or projected.
Spectroscopic studies on the mechanisms of adsorption of paraquat by humic acid and model compounds
Authors: Burns Ian G. , Hayes Michael H. B. , Stacey Maurice
Published: November 2006

Changes in the relative sizes of the carboxylic absorption bands in the infrared spectra (near 1730 and 1610 cm−1) of adsorbents before and after treatment with paraquat (1,1′‐dimethyl‐4,4′‐bipyridylium dichloride) showed that ion exchange is the predominant mechanism for adsorption of the bipyridyl by H+‐ ion saturated preparations of a humic acid from an organic soil, by two hydroquinone polymers and by two carboxylic ion‐exchange resins. Attempts to relate the extents of saturation (with adsorbate) of the exchange sites with the optical densities of the infrared bands were unsuccessful because of deviations from Beer's Law. Ultraviolet spectroscopy failed to provide evidence for charge transfer mechanisms in paraquat‐humic acid complexes in aqueous systems.
Studies on the persistence of the organotin fungicide fentin acetate (triphenyltin acetate) in the soil and on surfaces exposed to light
Authors: Barnes Roger D. , Bull Alan T. , Poller Robert C.
Published: November 2006

The results of a study into the persistence of triphenyltin (=fentin) acetate in soil are presented. The fungicide is degraded biologically 50% being decomposed in 140 days. The photochemical degradation of fentin acetate into inorganic tin via diphenyltin and monophenyltin compounds also is demonstrated. The leaching of fentin acetate in soil and its effect on soil nitrification is discussed.
Charges on fungal spores
Authors: Fisher D. J.
Published: November 2006

A survey is made of the use of microelectrophoresis to study surface charges on fungal spores in aqueous suspension. The method involves observation of individual spores under the microscope and measurement of rates of migration in a known potential gradient. Charge characteristics can be modified by specific chemical and enzymic treatments and provide a means of identifying surface ionogenic groups. The technique has also been used to demonstrate the presence of surface lipid. The surface components of a wide range of fungal spores are discussed. Studies of reactions of cationic fungicides at the surface of spores and stabilised protoplasts are also reviewed.
The degradation of quintozene, pentachlorobenzene, hexachlorobenzene and pentachloroaniline in soil
Authors: Beck JØrgen , Hansen Knud E.
Published: November 2006

The disappearance of quintozene (I) and its technical impurities and metabolites pentachlorobenzene (III), hexachlorobenzene (IV) and pentachloroaniline (V) from soil, was studied in laboratory experiments under controlled conditions during a period of about 600 days. The very high persistence found, was confirmed by the analysis of 22 samples collected from fields used for potato growing and treated regularly during the foregoing 11 years with commercial formulations of quintozene. In the laboratory experiments, III, V and methylthiopentachlorobenzene (VI) were found to be degradation products from the quintozene.
A note on the mode of action of the systemic fungicide tridemorph
Authors: Fisher David J.
Published: November 2006

The effects of the systemic fungicide tridemorph on fungal and plant protoplasts have been investigated. No evidence of reaction at the plasma‐membrane was revealed by microelectrophoresis. The fungicide did not affect oxygen uptake by fungal protoplasts but incorporation of labelled histidine was reduced. Fungi‐toxicity tests showed that tridemorph had little effect on spore germination but inhibited mycelial growth. It is suggested that the fungicide may act by interfering with the synthesis of proteins essential for hyphal extension.
The use of computers with chemical structural information: ICI CROSSBOW system
Authors: Eakin Diane R. , Hyde Ernest , Palmer Graham
Published: November 2006

Scientists ask several different types of question involving chemical structures with other property data. ICI has considered these question types in developing the CROSSBOW system for chemical structure recording and search. The system relies on the use of the Wiswesser Line‐Formula Notation to represent structures as compact, logical, unique and unambiguous codes suitable for computer processing.

The notations can be converted into detailed explicit descriptions of molecular structure known as connection tables. These allow the most exact atom‐by‐atom search technique for a specified atomic network anywhere in the molecule. To facilitate more general searches, and to provide a screen to reduce input to the exhaustive atom‐by‐atom procedure, two other chemical search techniques are implemented. The first is a fast search for the occurrence of certain chemical fragments, using a fragment set generated from the notations: the second is a search of the notations themselves for symbol strings relating to the required substructure.

Output from the search is in the form of structural diagrams generated from the connection tables. Data from associated property files can be displayed along with the structures, or searched as an additional parameter. The CROSSBOW system operates not only on ICI internal files, but also on commercially‐available data bases. These include the Aldrich chemical catalogue, the Index Chemicus Registry System current awareness tapes, and Hansch structure/activity files.
Determination of impurities in technical fenitrothion by liquid chromatography
Authors: Marshall W. D. , Greenhalgh R. , Bátora V.
Published: November 2006

Gas and liquid chromatographic methods were evaluated for determining the impurities in technical grade fenitrothion (≥95%). These impurities were S‐methyl fenitrothion. fenitrooxon, bis‐fenitrothion, S‐methyl‐bis‐fenitrothion and 3‐methyl‐4‐nitrophenol. The GC proved to be insensitive to the two bis compounds whereas these compounds could be analysed by liquid chromatography on a Corasil 11 column or on an OPN column.

Nine technical samples were analysed and S‐methyl fenitrothion, a potent anticholinesterase agent, was by far the most common impurity.
Analysis of foods for methomyl using thin‐layer chromatography after low temperature clean‐up
Authors: McLeod Harry A. , Mendoza Celso E. , McCully Keith A.
Published: November 2006

The recovery of methomyl from fortified food samples was determined semi‐quantitatively by a multi‐pesticide residue screening procedure with thin‐layer chromatography enzyme inhibition as the detection system. The estimated recoveries from milk, eggs, beef, honey, butter, pork, peas and cabbage were variable: 70–90% for samples fortified at 0.5 mg/kg and 40–90% for 0.05 mg/kg. Emulsion formation during liquid‐liquid partition was not encountered.
Coating and impregnating with endrin protects field‐sown douglas fir seed
Authors: Crouch Glenn L. , Radwan Mohamed A.
Published: November 2006

Chemically treated and untreated Douglas fir seed was evaluated in the laboratory and at four locations on National Forests in Oregon and Washington. Seed was treated by coating with endrin or endrin‐thiram and by impregnation with endrin. In the laboratory, germination was adversely affected by impregnation and by field exposure. Also, bioassays of treated seed showed no differences in consumption by deer mice among endrin treatments, but more seed was eaten after exposure in the field than before. Deer mice were the most common seed eaters found on all field study areas, and their numbers exceeded the level prescribed as a minimum requiring protection prior to seeding. Observations during and at the end of two growing seasons indicated that seedling production and stocking were much greater from endrin‐treated than untreated seed, but there were no significant differences among the three endrin treatments. In addition, performance of treated and untreated seed differed by area, with best results at the two locations known for favourable climatic conditions.
Metabolic aspects of the toxicology of diazinon. I. Hepatic metabolism in the sheep, cow, pig, guinea‐pig, rat, turkey, chicken and duck
Authors: Machin Antony F. , Rogers Heather , Cross Alan J. , Quick Michael P. , Howell Laurence C. , Janes Norman F.
Published: November 2006

The phosphorothionate insecticide diazinon was incubated with liver microsomes from the sheep, cow, pig, guinea‐pig, rat, turkey, chicken and duck. Metabolism by liver slices of most of these species was also examined. Hydroxydiazinon, isohydroxydiazinon, dehydrodiazinon, their oxons and diazoxon were identified and determined quantitatively or semi‐quantitatively. An eighth metabolite was tentatively identified as the 6‐aldehyde analogue of diazinon. Yields and rates of production of these metabolites varied greatly between species. Production of oxons was not generally correlated with susceptibility to diazinon poisoning, although it was lowest in the least susceptible animal, the sheep. The degradation of oxons by liver slices was too slow to explain the low toxicity of diazinon to the mammals. The relative importance of hepatic and extrahepatic metabolism in determining toxicity to vertebrates is discussed.
Some laboratory investigations relevant to the possible use of new pyrethroids in control of mosquitoes and tsetse flies
Authors: Barlow Fred , Hadaway Alan B. , Flower Leonard S. , Grose James E. H. , Turner Christopher R.
Published: November 2006

Cypermethrin, fenvalerate, permethrin, (S)‐α‐cyano‐3‐phenoxybenzyl (1R,cis)‐3‐(2, 2‐dibromovinyl)‐2, 2‐dimethylcyclopropanecarboxylate (NRDC 161) and (R,S)‐α‐cyano‐3‐phenoxybenzyl 2, 2,3, 3‐tetramethylcyclopropanecarboxylate (S‐3206; WL 41706) have been tested against adult mosquitoes (Anopheles stephensi) and tsetse flies (Glossina austeni). They possess many of the necessary characteristics such as high intrinsic toxicity, low volatility, and high stability but vary considerably in the contact action of their spray residues.
A simple method of determining the aqueous solubility of organic substances
Authors: Fürer Richard , Geiger Max
Published: November 2006

A new method is described in which a very fine suspension of the substance in water is diluted in a stepwise fashion; there is a sudden disappearance of the turbidity as soon as the aqueous solubility concentration range is reached. An instrument for micronising crystalline substances prior to the solubility determination has been designed. The method is simple and rapid and requires neither complicated apparatus nor analytical procedures. It is suitable for determining aqueous solubilities in the range from more than 1000 to less than 1 mg/litre. As a visual method, it would seem a priori to be less accurate than the “analytical” procedures recently described in the literature. When the solubility values given by different workers for the same substance are compared, however, discrepancies of a factor up to 10 are occasionally found. The accuracy obtainable with this new method readily suffices for the objective in view, namely to investigate to what extent the aqueous solubility of pesticide chemicals affects their behaviour during and after application. The aqueous solubilities of 34 commercial pesticide chemicals are tabulated; only in a few cases do the values obtained by the dilution method differ widely from those given in the 4th edition of the Pesticide Manual.
The effect of drop size and velocity on the performance of agricultural sprays
Authors: Lake John R.
Published: November 2006

The sizes and velocities of drops in sprays from farm sprayers are considered in relation to their impaction on plant surfaces. Examples from a study being carried out at the National Institute of Agricultural Engineering (NIAE) are given. The results showed that young leaves of barley (cv Mazurka) and wild oats (Avena fatua L.) were difficult to wet, only the smallest drops applied (about 100 um diameter) being readily retained. In the context of weed control in cereals the importance of detrmining the effect of the form of plant deposits on herbicidal activity is discussed, and examples of results of a joint study between the NIAE and the Agricultural Research Council Weed Research Organization are given.
Fenbendazole. I. Structure‐activity relationships
Authors: Loewe Heinz , Urbanietz Josef
Published: November 2006

Substitution of alkyl benzimidazol‐2‐ylcarbamates by phenoxy‐ or phenylthio‐groups in the 5‐position results in an increase in anthelmintic activity. The biological spectrum is altered by substitution of the phenyl ring. A sulphonic ester substituent in the 5‐position of the benzimidazole nucleus also increases anthelmintic activity.
The metabolism of the pyrethroid insecticide (±)‐α‐cyano‐3‐phenoxybenzyl 2,2,3,3‐tetramethyl‐cyclopropanecarboxylate, WL 41706, in the rat
Authors: Crawford Maureen J. , Hutson David H.
Published: November 2006

The metabolism of the pyrethroid insecticide α‐cyano‐3‐phenoxybenzyl 2,2,3,3‐tetramethylcyclopropanecarboxylate (WL 41706) has been studied in rats using two forms of 14C‐labelling (benzyl‐ and cyclopropyl‐). Excretion of benzyl−14C was rapid, 57% of the administered dose being eliminated in the urine 48 h after treatment and 40% in the faeces. No significant sex difference was observed. The amount of radioactivity excreted via expired gases was 0.005% of the administered dose and less than 1.5% of the dose remained in the animals 8 days after treatment. The mean percentage recovery of administered dose was 104% for male rats and 97% for female rats. Urinary and faecal metabolites from these rats, and from rats dosed similarly with [cyclopropyl−14C]‐WL 41706 were studied. The rapid metabolism of WL 41706 is due to efficient cleavage of the ester bond by rats in vivo to afford 2,2,3,3‐tetramethylcyclopropanecarboxylic acid (partly as glucuronide) and the 3‐phenoxybenzyl moiety. Before this cleavage occurs, however, about half of the intake suffers aryl hydroxylation giving the α‐cyano‐3‐(4‐hydroxyphenoxy)benzyl ester, part of which is excreted in the bile as a conjugate(s) and part of which is cleaved and eliminated as the O‐sulphate of 3‐(4‐hydroxyphenoxy)benzoic acid and the glucuronide of 2,2,3,3‐tetramethylcyclopropanecarboxylic acid. A minor amount of hydroxylation occurs at a trans‐methyl group on the cyclopropane acid moiety. The metabolism of WL 41706 by rat liver occurs mainly in the microsomes and mainly via oxidative processes.
Metamitron activity in tolerant and susceptible plants
Authors: Schmidt Robert R. , Fedtke Carl
Published: November 2006

The herbicidal activity of metamitron, its inhibition of photosynthesis and its metabolism were studied in a number of plant species. An enzymic, light‐independent deamination produces an inactive metabolite. Metabolism is rapid in plants tolerant to metamitron, e.g. Mercurialis annua and particularly sugar beet (Beta vulgaris L.), but slower in susceptible plants, e.g. Amaranthus retroflexus.
Kinetics of hydrolysis of atrazine in aqueous fulvic acid solution
Authors: Khan Shahamat U.
Published: November 2006

The hydrolysis of atrazine in aqueous fulvic acid solution followed first‐order kinetics with respect to the herbicide concentration. The half‐life of atrazine, calculated from first‐order plots, was lowest at low pH and increased as the pH of the reaction mixture increased. Increase in fulvic acid concentration resulted in a higher hydrolysis rate constant and a shortened half‐life but had no effect on the activation energy. However, the latter increased with increase in pH of the reaction mixture. The only product identified after hydrolysis in fulvic acid solution was 2‐ethylamino‐4‐hydroxy‐6‐isopropylamino‐1,3,5‐triazine.
Degradation of the herbicide [14C]‐diclofop‐methyl in soil under different conditions
Authors: Martens Rainer
Published: November 2006

The degradation of the herbicide diclofop‐methyl, ( ± )‐methyl 2‐[4‐(2,4‐dichloro‐phenoxy)phenoxy]propionate, was investigated in two agricultural soils under aerobic and anaerobic conditions. Using two differently labelled forms of [14C]‐diclofop‐methyl the qualitative as well as the quantitative formation of extractable metabolites was followed for 64 days. The mineralisation of the uniformly labelled aromatic rings was pursued by monitoring the 14CO2 generated for 25 weeks. As a first step of the degradation a very rapid hydrolysis of the ester bond was detected under all conditions. Diclofop, the corresponding substituted propionic acid formed, was extensively degraded under aerobic conditions, the final product being 14CO2. As an intermediate, a compound later identified by GLC/MS to be 4‐(2,4‐dichlorophenoxy)phenol, was found in the extracts. Furthermore, traces of six other unknown metabolites were detected. Under anaerobic conditions the degradation proceeded to a small extent. At most 3% of the applied radioactivity was accounted for by the degradation product 4‐(2,4‐dichlorophenoxy)phenol. No other metabolite, including 14CO2, was observed, implying lack of any further degradation.
Some studies on the use of alginates for the placement and controlled release of diquat on submerged aquatic plants
Authors: Barrett Philip R. F.
Published: November 2006

Viscous solutions of sodium alginate can be extruded under water in the form of a string which will stick to weeds. The sodium alginate reacts with calcium ions to form an insoluble gel of calcium alginate so that the strings become more firmly attached to the weeds. Diquat dibromide can be incorporated into the alginate and this is slowly released into the water close to the plants. Two experiments are described in which this technique is tested in a fast‐flowing river and for localised control in a lake. Diquat dihromide was found to be effective, when formulated with alginate, on Ranunculus spp. in the river and Groenlandia densa in the lake.
Mechanisms of photo‐oxidation reactions
Authors: Davidson Robert S.
Published: November 2006

The factors affecting photochemical production of radicals, the reaction of these radicals with oxygen, the factors affecting the formation of singlet oxygen and superoxide anions and the reactivity of these species are discussed. The effect of the medium upon the course of photo‐oxidation reactions and methods for investigating the mechanisms of these reactions are summarised.
Photolysis of organophosphorus insecticides on soil surfaces
Authors: Burkhard Niklaus , Guth Johann A.
Published: November 2006

Photolysis on soil surfaces of the organophosphorus insecticides diazinon, methidathion and profenofos was studied under artificial sunlight conditions. All three compounds were readily degraded under the conditions used. The rate of degradation decreased in the order diazinon, profenofos, methidathion and was always greater in moist than in dry soil. The same order of stability was also observed from photolysis studies in aqueous solution. The major photolysis products identified were 2‐isopropyl‐6‐methylpyrimidin‐4‐ol from diazinon, 5‐methoxy‐3H‐1,3,4‐thiadiazol‐2‐one from methidathion and 4‐bromo‐2‐chlorophenol and 4‐bromo‐2‐chlorophenyl ethyl hydrogen phosphate from profenofos. The same compounds were formed in hydrolysis studies and also upon photodecomposition in aqueous solutions of diazinon and methidathion. Profenofos, however, showed a different photolytic reaction in aqueous systems, forming O‐(2‐chlorophenyl) O‐ethyl S‐propyl phosphorothioate. Soil photolysis studies together with hydrolysis experiments could be a useful quick method for obtaining early information on the chemical breakdown products which are to be expected in the soil environment.
Kinetics of linuron and metribuzin degradation in soil
Authors: Kempson‐Jones Gillian F. , Hance Raymond J.
Published: November 2006

The disappearance of linuron and metribuzin was studied during laboratory incubation of soil samples which had been taken from several depths at three sites, and treated with the pesticides. Temperature and water content of the soils were varied. There was a tendency for the rate of loss to be slower in soil taken from deeper horizons than in surface soil but the differences were not large. In only ten out of forty experiments did the value 1 for the apparent order of reaction fall within 95% confidence limits. In the remaining experiments the apparent reaction order was greater than 1 with eight values higher than 4. For one soil, the reaction order for linuron was markedly lower for incubation at 22°C compared with incubations at 10°C. The results could be explained on the basis that the systems were complex, involving consecutive or competing reactions. An alternative possibility is that the apparent complexities were artifacts brought about by the inherent limitations of the laboratory incubation system.