The action of Di-(p-chlorophenyl) trichloromethylcarbinol (DTMC) and Di-(p-chlorophenyl) trifluoromethylcarbinol on houseflies

Résumé L'action des carbinols di-(p-chlorophenyl) trifluorométhyl et di-(p-chlorophenyl) trichlorométhyl (DTMC) a été déterminée sur une souche très résistante de mouches par la méthode de contact. Le premier composé semble agir probablement grâce à de faibles propriétés fumigantes, alors que le second est toxique par contact. L'action toxique de ce dernier est sensiblement augmentée par l'addition du DDT, DDE ou autre composé organique de la série du DDT.

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Chemical development of DTMC.

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Biological evaluation.     

A cycloisomerization reaction of Di-(p-halogenophenyl)-trifluoromethyl-carbinols

Résumé Une solution de di-(p-chlorophényl)-trifluorométhyl-carbinol dans l'acide sulfurique concentré, diluée à l'eau ou au méthanol, donne naissance à du chloro-3-hydroxy-(ou méthoxy-)-6-trifluorométhyl-9 fluorène. Le composé méthoxylé, après l'alcoolyse alcaline du groupement-CF₃, a été dégradé au fluorénone correspondant, dont la synthèse a été realisée indépendamment.     

Synthesis and reactions of a proposed DDT metabolite, 2,2-bis(p-chlorophenyl)acetaldehyde

Zusammenfassung Es wird eine Methode beschrieben, nach der authentischer 2, 2-bis(p-chlorphenyl)acetaldehyd erhalten wird. Die Charakterisierung dieses Aldehyds hat gezeigt, dass die in der Literatur bisher erschienen Angaben unrichtig sind. Der Aldehyd geht unter milden oxydativen Bedingungen unter Deformylierung in 4, 4-Dichlorbenzophenon Über. Mögliche biologische Bedeutung dieser Reaktionen werden diskutiert.     

Di- and tripeptides containing homoleucine: synthesis and biological assays on insects

Summary Some di- and tripeptides containing homoleucine (2-amino-4-methylhexanoic acid) have been synthetized. These compounds have been submitted to biological tests on insects for their hormonal activity in comparison with the known tripeptide pivaloyl-alanyl-p-aminobenzoic acid ethyl ester. Only 2 of them (3 and 4) caused morphological changes on larvae ofPyrrhocoris apterus.This work has received financial support from the Consiglio Nazionale delle Ricerche.The biological assays were done in the Research Center of Montedison S.p.A. (Linate, Milano); the collaboration of Dr G. Michièli is gratefully acknowledged.     

聚合质量比对Sr0．7La0．15Ce0．15Fe11.7Zn0．3O19／PAn复合体系微波吸收性能的影响

用原位聚合法制备了Sr0．7La0．15Ce0．15Fe11.7Zn0．3O19铁氧体／聚苯胺（PAn）复合材料。采用X射线衍射（XRD）、扫描电子显微镜（SEM）对样品的结构、微观表面形貌和粒子大小进行了表征，用微波矢量网络分析仪测量样品在2～12．4GHZ频率范围内复介电常数和复磁导率，根据测量数据计算微波反射率R与频率f的关系。研究结果表明：PAn包覆于掺杂锶铁氧体表面，PAn／Sr0．7La0．15Ce0．15Fe11.7Zn0．3O19复合材料具有良好的吸波性能，随着掺杂锶铁氧体含量的增加，微波吸收匹配厚度和吸收带宽发生变化：当Sr0．7La0．15Ce0．15Fe11.7Zn0．3O19聚合质量比为40％时，最佳匹配厚度为2．6mm，吸收峰值接近-40dB，峰值频率高于12．4GHz，大于10dB吸收带宽预计达到55GHz。     

Amperometric studies on chromium (III) and iron (III) hydroxocyanotungstates (IV)

Zusammenfassung Die Zusammensetzung von in wässeriger Lösung gebildeten Ionenpaaren des Anions [W(CN)₄(OH)₄]^4- mit Cr³⁺ bzw. Fe³⁺ wird amperometrisch ermittelt.

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Acknowledgment. The authors are grateful to Dr.S. M. F. Rahman for providing necessary facilities and C.S.I.R. (India) for awarding a Junior Fellowship to one of them (K. U.).     

Hashish VI1: Conversion of (-)-Δ 1(6)-Tetrahydrocannabinol to (-)-Δ 1(7)-Tetrahydrocannabinol. Stability of (-)-Δ 1 and (-)-Δ 1(6)-Tetrahydrocannabinols

Zusammenfassung Die Synthese von (—)-¹⁽⁷⁾-Tetrahydrocannabinol (THC) auf (—)-¹⁽⁶⁾ wird beschrieben. Das Hauptprodukt der oxidativen Zerstörung von (—)-¹-THC ist Cannabinol. Beschleunigte Versuche der Luftoxidation von (—)-¹-THC und (—)-¹⁽⁶⁾-THC haben gezeigt, dass das letztere beständiger ist. Dieser Unterschied kann mit der Reaktivität des C₃-benzylisch-allylischen Wasserstoffes in (—)-¹-THC erklärt werden.     

Effects of Si and Ce on the microstructure and hydrogen storage property of Ti_(26.5)Cr_(20)V_(45)Fe_(8.5)Ce_(0.5) alloy

In this paper,the effects of Si and Ce on the microstructure and hydrogen storage property of Ti26.5 Cr20V45Fe8.5Ce0.5 alloy were studied,respectively.First of all,effects of Si on the microstructure and hydrogen storage properties of Ti26.5Cr20(V45Fe8.5)1-xSixCe0.5(x=0,0.5,1.0,1.5 and 2.0 at%)alloys were studied by X-ray diffraction,scanning electron microscopy and P-C isotherm measurements.As the Si addition increases,the hydrogen absorption capacities of alloys decrease but the equilibrium pressure incre...     

Das Elektrovenogramm (Evg) der isolierten Flughautvene (Chiroptera)

Summary The electrovenogram of the isolated vein of the wing membrane (Chiroptera) exhibits two main irregularities in its diphasic action current—a fast initial wave before the beginning of the systole and a very protracted after-wave. Following this the rise and fall of potential run parallel with the contraction and dilatation of the vessels.     

Serological relationships of frogs (Ranidae) and toads (Bufonidae)

Zusammenfassung Das Ergebnis der immunoelektrophoretischen Untersuchungen zeigt einen gewaltigen Unterschied in den serologischen Mustern der Frösche (Ranidae) und Kröten (Bufonidae). Die amerikanischen Vertreter der Ranidae und der Bufonidae haben sehr wenig gemeinsame Serumantigene. Der Mangel an gemeinsamen antigenischen Bestandteilen in ihren Serumproteinen weist sowohl auf eine frühe Evolutionstrennung des Frosches und der Kröte wie auch auf ein merkliches genetisches Auseinandergehen der zwei Stämme während der langen Zeitspanne isolierter Existenz hin.

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The work was supported by grant No. GM-11782 from the U.S. Public Health Service.     

Supernumerary (B) chromosome inAnopheles indefinitus (Diptera,Culicidae)

Summary Larval brain mitotic karyotype ofAn. indefinitus from Kanchanaburi exhibits a supernumerary (B) chromosome which is apparently common in that population. 1 or 2 B-chromosomes have been observed in the samples from 5 isofemale lines examined.Acknowledgments. We thank K. Mongkolpanya and P. Kittayarak for species identification. Part of this work was supported by Mahidol University Research Fund and AFRIMS.     

Theory (In-)Equivalence and conventionalism in f(R) gravity

f(R) Gravity is the most natural extension of General Relativity within Riemannian Geometry. Due to (inter alia) its potential capacity for a unified treatment of early and late-time cosmic expansion, it has enjoyed recent attention in astrophysics and cosmology. I critically examine three inter-related claims found in the pertinent physics literature, of general interest to the philosopher of science. 1. f(R) Gravity is equivalent to a particular Brans-Dicke Theory. 2. The spacetime geometry underpinning f(R) Gravity has substantial conventional elements. 3. f(R) Gravity is an instance of a theory in which the distinction between matter and spacetime is conventional. Whilst the first claim can be vindicated in precise terms, the remaining two claims, I submit, are unwarranted – at least for the reasons usually adduced. On different grounds, though, the case for conventionalism about spacetime geometry in f(R) Gravity (as well as General Relativity) turns out to be considerably stronger.     

Satellite DNA (II) from sea urchin (Lytechinus variegatus) sperm

When DNA isolated from freshly collected sperm of sea urchin (Lytechinus variegatus) is centrifuged to equilibrium in CsCl, 2 heavy satellite bands appear beside the main band DNA. Satellite DNA (II) appears in between the main band DNA (rho = 1.695 g/cm3) and the rDNA satellite (rho = 1.722 g/cm3). Satellite DNA (II) has a buoyant density 1.710 g/cm3, corresponding to 50% GC content. It is speculated that the satellite DNA (II), which appears to be of high mol. wt, might contain the sequences complementary to histone mRNA.