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The electrophoretic mobility of an inosamine in borate buffer is very dependent on configuration, and a set of 10 inosamines showed a wide range of mobilities. The order of mobilities within the set changed as the pH of the buffer was changed in the range 7.7-9.5. Paper electrophoresis in borate buffers can effectively separate mixtures of inosamines. The probable site of reaction between an inosamine and borate ions has been identified for some isomers. In aminodeoxy-scyllo-inositol and 3-amino-3-deoxy-epi-inositol the amino group is involved in the formation of a tridentate borate complex of adamantane-type structure, which is electrically neutral over the above range of pH values. Aminodeoxy-scyllo-inositol simultaneously combines with a second molecule of borate, forming a bis-tridentate complex with one anionic centre. There is evidence that in other isomers protonation of the amino group and formation of anionic borate complexes at hydroxyl groups are not independent reactions. Paper electrophoresis in non-complexing buffers provides evidence for the relative basicities of inosamines. DL-2-Amino-2-deoxy-epi-inositol, which has an interaction between axial amino and hydroxyl group in the preferred conformation, was the strongest base in the set, whereas the bases with an axial amino group free of such an interaction were the weakest. Inosamines form N-carboxyl derivatives in the normal way on exposure to carbon dioxide in the presence of strong alkali.

Measurements of ionic mobilities of a number of cations and anions in nonaqueous and mixed solvents were made from electromigration on filter paper, and the apparent advantages of the ionophoretic method over other modern techniques have been explained. The values so obtained have been corrected for (a) electroosmotic and (b) tortuosity (i.e., ‘added migration path length’) effects, in order to compare them with those in free solution. Considering the combined effect of dielectric constant and viscosity the ionic mobilities obtained by the electrophoretic method are considered to be of correct order of magnitude. The ionic mobilities at constant dielectric constant when plotted against reciprocal of viscosity show a slight deviation from linearity.

The electroless gold plating process using potassium borohydride as the reducing agent has been investigated for impur i ty effects, material compatibili ty, bath agitat ion effects, and thickness uni formi ty and line resolution in selective plating of pat terned substrates. Impuri t ies may cause a decrease in plat ing rate [Ni(II) ], bath instabi l i ty [Ni( I I ) , Co(II) , Fe ( I I ) ], thickness nonuni formi ty (polyethylene, organics in deionized water) , and nodule format ion (some surfactants) . Bath agitat ion is beneficial: it increases plat ing rate, minimizes porosity of thin deposits, and eliminates nodule formation. Edge bui ld-up general ly occurs in selective pat tern plating but, with proper selection of bath compositions and agitation conditions, it can be main ta ined below 10% in the thickness range of 1-12 ~m. The rate of lateral growth of electroless gold deposits is about 60% of that of perpendicular growth under opt imum plating conditions. Also considered in this paper are certain aspects of the scale-up and waste disposal problems associated with electroless gold plating. Electroless gold plat ing has been found to be useful in a variety of applications, especially for selective plat ing on pat terned substrates for electronics applications. Such applications general ly require pure soft gold with a thickness in the range of 1-15 ~m. A bath developed in this laboratory (1) has been found to be quite suitable for forming such deposits. Previous papers described the general bath characteristics (1), physical properties of deposits (2), bath operation with replenishment (3), reaction mechanism (4), and the nucleation and growth of deposits (5). The purpose of this paper is to describe several other aspects of the process which are important from the practical viewpoint and which have hitherto not been discussed. The topics covered include impur i ty effects, mater ial compatibility, bath agitation effects, deposit thickness uniformity, and line resolution in selective plat ing of fine line pat terned substrates. General recommendations are made as a guide for users of this process. Specific applications will be described in separate communications. Solution Preparation and Plating Procedure Compositions of three electroless gold plat ing baths used are listed in Table I. Bath A was used often in our earlier studies (1-3) including those of impur i ty effects and porosity described in this paper. More recently, baths B and C have been used exclusively. These two baths contain less KCN and KBH4 and, therefore, are more preferable than bath A for practical reasons. Bath B gives the highest deposition rate (5-7 ~m/hr at 70~176 with vigorous agitation), but deposits with acceptable physical properties can be obtained only when plated with agitation. Bath C is slower plat ing (2 ~m/hr at 70~ with agitation) but gives bet ter thickness uni formi ty on th in deposits in fine l ine plating. Details wil l be described in subsequent sections. It is convenient to prepare the baths by di lut ion of 5• concentrated stock solutions. These solutions can be stored at room temperature for at least three months without noticeable decrease in pla t ing rate. Since a very small amount of hydrogen gas " Electrochemical Society Life Member. "" Electrochemical Society Act ive Member.

Filtration and subsequent weighing or microscopic evaluation of trapped particles is a method most commonly used to determine concentration of aerosol. The granulometric study of particles has been hitherto made only with use of membrane filters. In the present paper a process of making transparent the fibre filters by organic solvents even for very dense samples used for gravimetric determination of the aerosol concentration is described. The results are compared with those achieved during simultaneous measurement with the membrane filters. The fibre filters are used to determine weight concentration of aerosol. However, they may be employed also for granulometric evaluation of trapped particles. According to the surface concentration of particles on a filter, a suitable procedure is needed, making use of the fact that in an organic solvent or in its vapours, the fibre structure of a filter disappears and a thin layer containing trapped particles is produced. This transparent layer allows microscopic photographing of particles trapped by the filter. It is of advantage that the same sample of the aerosol may be used both for the determination of the weight concentration and for the determination of the size of the trapped particles. Resulting distribution curves of the size of particles simultaneously taken in the atmosphere by the fibre as well as membrane filters are compared. Accordance between the distribution curves obtained using the fibre and membrane filters is satisfactory for the investigation of the atmospheric aerosol. The problem of aerosols is at the present time involved in many fields of interest. In the last few years, properties of aerosols in the atmosphere and stratosphere have been followed particularly from the viewpoint of the environment protection. Here, the fibres increasingly assert themselves because of their favourable properties. In Czechoslovaki a, the microfibre filters AFPC, made of chlorinated polyvinyl chloride and manufactured as flat analytical filters, are used to measure weight concentration of dust. The trapped particles can be dispersed in water or another liquid by a mere mechanical washing, and the suspension thus produced can be employed for microscopic evaluation of the size of particles. At the same time, however, change in shape of original aggregates, as well as loss of solutes and losses on the walls of the vessel, in which the filter is being washed, take place. The dust particles trapped inside a AFPC filter cannot be usually washed away even when using detergents. The size of particles trapped by a membrane filter can be determined with an electron microscope, using a method for the study of the filtration surfaces1'2. Papers dealing with microscopic determination of size of the aerosol particles directly on the fibre surface of a filter are unknown to us. Making use of good experience with the

This paper reports studies of the reactions of fluorine atoms and several aromatic and heterocyclic molecules. As in earlier work we have used the method of crossed molecular beams to create long‐lived reaction intermediates and to deduce from the angular distribution of the product molecules information about the energy distribution in the reaction complex. The data reported in this paper complement those collected earlier. They show that when a light group is emitted from a reaction complex randomization of the internal energy of the complex is not more rapid than reaction. When a heavy atom is emitted from the reaction complex the limited data available indicate that almost all vibrational degrees of freedom of the complex participate in the reaction. This latter observation provides an interesting connection between vibration‐translation energy exchange and the mechanism of chemical reaction.

The gas‐phase microwave spectrum of the gauche rotational isomer of propanal (propionaldehyde, CH3CH2CHO) has been studied in detail. Vibration‐rotation interaction between torsional energy levels which are split by quantum tunneling results in the splitting of several ground‐state absorption lines. Treatment of this interaction by methods described in an earlier paper successfully accounts for the anomalous spectrum. Observation of several predicted transitions (including transitions nominally forbidden) confirms the theoretical treatment and allows an accurate determination of the energy level splitting (471.80±0.07 MHz) of the two lowest levels of gauche propanal. This new information is used in the determination of an internal rotation potential, which is compared with recent theoretical calculations for propanal.

In recent years optical methods have been extensively applied to assist in the elucidation studies of electrochemically induced phenomena. The objectives of these studies have been: (i) the characterization of the surface and electronic states of conducting and semiconducting materials; (ii) the in situ detection, characterization and kinetic monitoring of electrolytically generated reactive intermediates or products: (iii) the determination of the amount of coverage of surface adsorbed molecules and ions and their adsorption sites; and (iv) the electronic structure and physical properties of these adsorbed states. Three principal optical techniques have been employed: normal transmission spectroscopy, internal reflection spectroscopy and specular reflectance or ellipsometry. The first two techniques require the electrode to be at least partially transparent to the optical radiation. With the attainment of high sensitivity to small changes in radiation made possible by modulation and signal averaging methods, it has been demonstrated that considerable detailed description can be made regarding electrochemically induced surface changes as well as reactive intermediates in electrode mechanisms. The present state-of-the-art of spectroelectrochemistry is examined and reviewed in this paper. In den letzten Jahren wurden optische Methoden in grosem Umfang bei Untersuchungen zur Aufklarung elektrochemisch verursachter Phanomene herangezogen. Ziele dieser Untersuchungen waren: 1. Charakterisierung der Oberflache und der elektronischen Zustande von leitenden und halbleitenden Materialien; 2. Nachweis in situ, Verfolgung der Kinetik und Charakterisierung elektrolytisch erzeugter reaktiver Zwischenstufen oder Produkte; 3. Ermittlung der Oberflachenbedeckung durch adsorbierte Molekule und Ionen sowie deren Adsorptions-stellen; 4. elektronische Struktur und physikalische Eigenschaften dieser adsorbierten Zustande. Im wesentlichen wurden drei optische Verfahren eingesetzt: normale Transmissionsspektroskopie, innere Reflexionsspektroskopie und Spiegelreflexion oder Ellipsometrie. Bei den beiden ersten Methoden mus die Elektrode fur die optische Strahlung wenigstens teilweise durchlassig sein. Nachdem durch Modulations-und Signalmittelungsverfahren eine hohe Mesempfindlichkeit fur kleine Schwankungen der Strahlung erreicht worden war. wurde gezeigt. das elektrochemisch verursachte Oberflachenanderungen sowie reaktive Zwischenprodukte bei Elektrodenmechanismen ziemlich detailliert beschrieben werden konnen. Diese Veroffentlichung gibt einen Uberblick uber den gegenwartigen Stand der Spektroelektrochemie.

Linear plots of reaction rate vs reciprocal of solvent viscosity are generally used as the classifying criteria for diffusion controlled reactions in fluid solutions and to determine reaction mechanisms in mixed hydroxylic solvents like glycerol and water. This paper presents data which shows that the above-mentioned criteria are insufficient in many cases where nonideal mixed solvent systems are used to increase solvent viscosity. Data correlations suggest that the excess functions determine the variation in reaction rate constants. Kinetic parameters are presented for sucrose-water and methanol-water solvent systems for a reaction involving Fe(CN)6 and zinc uroporphyrin.

The sesquiterpenes of ginseng have been studied. From the volatile oil, fifteen compounds were characterized. Three of those compounds, α-panasinsene,β-panasinsene and β-neoclovene, were new compounds and were characterized in this paper. Panasinsenes are considered as intermedial compounds in isomerization of caryophyllene to neoclovene.

Two modes of operation of a flow electrolytic reactor are considered, one consisting of a recycle of a solution between the reactor and a tank, and the other consisting of flowing the solution only once through the reactor. The times of electrolysis to a given final degree of conversion for the two modes of operation of a given reactor are calculated and compared. In the second part of the paper the case of a reaction of ece or ec mechanism going on in a flow electrolytic reactor is considered. Using kinetic theory for two consecutive first-order reactions, equations are derived allowing to calculate the value of the flow rate corresponding to the formation of a maximal concentration of an intermediate electrolytic product, and the value of the concentration. Numerical solutions of the equations are given for two porous electrodes differing in length.

The reaction between dinitrogen oxide and RU(NH~)~OH,~+ to form the dinitrogen complexes of pentaammineruthenium(11) was investigated. At high pressures of N20 the Br, I, BF4 and PF, salts of RU(NH~)~N~O~+ were isolated. The compounds were characterized and their aqueous chemistry compared with that of the corresponding salts of Ru(NH&0H2'+ whose preparation and characterization are also reported here. The infrared spectra and X-ray powder patterns of the dinitrogen oxide complexes are reported. Dinitrogen oxide and pentaammineaquaruthenium(~~) are known1 to react according to RU(NH,),OH,~+ +N20 s RU(NH,)~N~O" + H20 (1) and Ru(NH3),N202+ +2e+2Hf + Ru(NH3),NZ2+ +H,O (2) At a pressure of one atmosphere of dinitrogen oxide and at low concentrations of ruthenium(11) about 10% of the ruthenium@) is present as the dinitrogen oxide complex,' at higher concentration^^,^ RU(NH,),OH,'+ acts as a reducer, forming the dinitrogen complexes Ru(NH3),NZ2+ and (Ru(NH,),),N;'. In the presence of an external reducer the dinitrogen complexes are formed in high yield^.^ If a high pressure of dinitrogen oxide is used the dinitrogen oxide complex can be isolated. Isolation of the fluoroborate salt has been reported in a preliminary communication4 and further details of that work together with the isolation and investigation of the properties of other salts of the complex cation are reported in this paper. The isolation and characterization of several salts of pentaarnmineaquaruthenium(~~) are also reported here because the solution properties of this complex were used to characterize the dinitrogen oxide complexes. Bottomley and Crawford5 have recently prepared the dinitrogen oxide complexes by the reaction of [Ru(NH,),NO] Cl, with hydroxylamine and hydrazine.

The results of a study on a large pulse surface photopotential of P type silicon electrodes (10 Ω cm) immersed in 0·1 M Na2SO4 solutions of various pH are discussed in the paper. The derivative ∂(ϕs — ϕs)/∂ pH has been determined and has been found to be −60 mV in the pH range from 1 to 9. The derivative ∂(ϕs — ϕb)/∂ U has been evaluated from theoretical considerations and experimental results to be 0·5 for the studied solutions in the potential range where the dependence of (ϕs — ϕb) on U is linear.

The reduction of [Ru(Hedta)(H2O)] at the mercury electrode and the subsequent chemical reactions in buffer solutions were investigated by AC and DC polarography and by large-scale electrolysis. Two polarographic steps were observed; the more positive step is discussed in this paper. The step was a diffusion-controlled, one-electron reduction of ruthenium(III) to ruthenium(II). For [H+]=(10−3–10−5) mol dm−3 the reduction was reversible, and it became less reversible if [H+]

Synopsis: With the addition of titanium tetrachloride, silyl enol ethers can react with either aldehydes or ketones forming crossed aldol products. The carbonyl group of the aldehyde or ketone is activated by titanium tetrachloride, allowing for nucleophilic attack by a silyl enol ether at the carbonyl carbon (a titanium chelate forms as an intermediate). This addition reaction is dependent upon the metal salt, solvent, and temperature used. Critique: The fact that various reaction conditions were studied to find optimal reaction conditions that gave the highest yield of cross-aldol addition products strengthened the findings in this paper. Mukaiyama and coworkers concluded first that titanium chloride was best for this reaction compared to boron trifluoride etherate and stannic chloride. Secondly, it was observed that methylene chloride gave cross-aldol products in good yield while no reaction was observed in both diethyl ether and THF. Finally, reaction with aldehydes is favored at -78 o C while ketone reaction is favored at room temperature. It was also interesting to see that the use of unsymmetric ketones allows for regiospecific addition reactions at the olefinic position on the silyl enol ether.

A novel method of isolation of chicken pepsins by chromatograph y on Sepharose 4B with a covalently attached mercury derivative is described. The chief advantages of this isolation procedure are a 6-fold increase of the specific activity of the preparation in one operation and minimum losses of active material. The preparation obtained was resolved into 4 individual forms by chromatography on DEAE-cellulos e. All forms showed the presence of N-terminal serine. They have the same specificity when tested with the B-chain of oxidized insulin as substrate; this specificity differs from that of hog pepsin. The molecule of chicken pepsin and its zymogen, unlike other animal pepsins so far known, has a free thiol group1'2. This thiol group is obviously located on the surface of the molecule and in native unmodified pepsin it can be not only titrated but also chemically modified3. We considered therefore worthwhile to use the presence of this free SH-group for the isolation of chicken pepsin by affinity chromatography. In this paper we report on the isolation of chicken pepsin on a mercurial Sepharose column and on the resolution of its individual forms and their characterization.

Derivatives of 5H-thiazolo[3.2−a]thieno[2.3−d]pyrimidine(A), 5H-[1]benzothieno[2.3−d]thiazolo[3.2−a]pyrimidine (B), 4H-thiazolo[3.2−a]thieno[3.2−e]pyrimidine (C) and 5H-[1]benzo-thieno[3.2−e]thiazolo[3.2−a]pyrimidine (D) were synthesized by various methods. Similar reactions are leading to derivatives of thieno[2′.3′∶4.5]pyrimido[2.1−b][1.3]thiazine (E) and [1]benzothieno[2′.3′∶4.5]pyrimido[2.1−b][1.3]thiazine (F).C, D, E, andF are new heterocyclic ring systems. Detailed papers will appear soon.

The fractionation of the tritiated water (HTO) was examined during the crystallization of hydrates, such as (COOH)2·2H2O, (COOK)2·H2O, Cu(HCOO)2·4H2O, and Sr(HCOO)2·2H2O. The dilution of HTO in the organic salts was found to be comparable to that in inorganic salts observed previously. The fractionation of HTO was explained on the basis of an ionic process in an aqueous solution, and the crystal growth mechanism, in a way similar to that described in a previous paper. On the contrary, a considerable dilution was observed for oxalic acid dihydrate. The proton effect on the fractionation in both the ionic and dehydration processes was also discussed.

The thermodynamic properties of dilute solutions of in the ternary system have been investigated by the measurement of the reversible emf of the formation cellThe partial molar properties of have been found to be in good agreement with values predicted by the complex‐ion model reported in previous publications from this laboratory (1–3). In the present paper it is shown that these rather involved expressions reduce to useful, simple equations of the formwhere represents either an integral or a partial molar property. The ternary solution is denoted by the subscripts 1,2,3, while the two binaries, each containing the reactive‐metal chloride, are denoted by 1,2 and 1,3; is a concentration variable. It is also shown that the following expression applies to the activity of the reactive‐metal chloride (component 1) in solutionFor dilute solutions obeying Henry's law, the activity coefficients are given bywhere is the Henrian activity coefficient in the binary i,k and is the mole fraction of present in the ternary solution, providing that in the ternary 1,2,3 is the same as that in the two binary solutions 1,2 and 1,3.

In the bending of symmetrically loaded circular plates of brittle material, e.g. glass, which are supported between flexible gaskets at the periphery, large errors can result in estimating the stresses and deflections in the plate if it is assumed that the plate is simply supported. This paper uses the exact numerical solution, given elsewhere, in comparing the exact stresses and deflections with those obtained by assuming simply supported edges. It is shown that gasket width and stiffness are important in controlling the maximum stress. The deviation from an assumption of simple support is greatest when the plate is thin.

Glassy and crystalline substances in NaPOs-MoOg system with P/Mo ratios from O.1 to 300were prepared by heating of NaPOs glass and molybdenum trioxide mixtures at 580, 700, or 750gC. The products were smbjected. to paper-chromatograPhic analysis, X-ray diffractometric measurement, and IR spectrophotometitic measurement. The prodqcts prepared at 580eC with PIMo ratios from O.1to 3. contained crystallin6 sodiummolybdenum oxide phosphate(NaMo02PO4). Since the average chain length of condensed phosphates present in the products increased with increasing P/Mo ratio, it could be concluded that NaPO391ass reacted with molybdenum trioxide to form P-O-Mo linkage, Assuming that the glassy products with P/Mo ratios larger than 5.0 had P P, P-O, P-O-Mo, and Mo-O linkage C a theoretical treatment of the degree of polymerizatien of condens. ed phosphates has. been made and compayed, with the experimental data, and reasonable chemical structure of glasses in NaPOs-MoO5 system were concluded as MoO2(PO)2, MoO2(PO)g, or MoO2(PO) The absorption at 870N930 cm-i in IR Spectra of the products with P/Mo ratios smaller than 5.0 were conSidered to be due to P-O-Mo /stretching.

This paper reports the i.r. and Raman spectra of the four solid phases of GeH4. Pure and mixed isotopic crystals have been examined. Marked spectral changes are observed at every transition. The interpretation of the spectra, based upon the Halford–Hornig approach, provides information on the crystal structure of each form. Phase I is plastic and molecules probably lie at sites of symmetry T or Td. The spectra of the two intermediate phases are consistent with site symmetries of either D2d, S4, C3v or C3 but the two former are favored. The stable phase below 63 °K is of lower symmetry, the molecules lying at sites of either D2, C2v, C2, C5, or C1, symmetry. Possible factor groups are proposed for phases II, III, and IV. The molecules are found to occupy only one set of equivalent sites in each of the phases.

Electron impact excitation functions for the formation of metastable states of benzene, toluene, and aniline are measured under low pressure conditions (∼1 × 10−5 torr) with an electron energy resolution of 0.3 eV. Considerable evidence is presented for assigning these metastables as the lowest triplet states T1. Each excitation function exhibits several features at low electron energy (4–15 eV), which are interpreted in terms of resonances which decay to give T1 and nonresonant exchange excitation processes. Comparison of these triplet excitation functions with the optical excitation functions for fluorescence (see the preceding paper) indicates that intersystem crossing does not make a major contribution to T1 formation under the present experimental conditions. From time‐of‐flight measurements a lower limit of 500 μsec is estimated for the lifetime of the lowest triplet state T1 for these three molecules.

This paper reports experimental studies of the nonradiative lifetimes of individual vibronic levels of several partially deuterated benzenes. The different deuterated species transform according to different symmetries, and therefore the number of totally symmetric modes differs from molecule to molecule. The observed rates of nonradiative decay fall into a regular pattern as a function of increasing deuteration. This observation, together with theoretical arguments, suggests that the accepting modes are, to a good approximation, local modes. Comparison of the predicted relative nonradiative rates with those observed is generally good, but not as accurate as for C6H6 and C6D6. The likely source of the discrepancy is discussed.

This paper reports a study of the water vapor pressure and low level sodium impurity dependence of the oxidation rate of silicon at 1000° and 1230° C. The oxidation studies were carried out in an rf heated cold wall oxidizer which is also described. The important aspect of the oxidizer is that the sample is placed between two closely spaced silicon blocks to give a very uniform temperature region and therefore uniform oxide properties. It is shown that the oxidation rate coefficient (in the parabolic range) increases monotonically with water vapor pressure. However, the rate also shows some dependence on the other gas phase constituents. At constant partial pressure the parabolic rate constant increases, going from mixture to pure (vacuum) or mixture. For sodium concentrations in the range 0.4–10 ppm (atomic) in the water vapor atmosphere no changes in oxidation rate were observed at 1000° or at 1230° C.

This paper describes the effect of solution pH on the passive film on iron which was investigated by ellipsometry and by cathodic reduction combined with chemical analysis. Anodic two-step passivation was employed to exclude anodic deposition of ferrous ion, resulting from anodic oxidation of iron. The film in acid solution is almost anhydrous oxide, whereas the film in neutral and alkaline solution has an outer hydrated oxide layer, whose thickness decreases with decreasing pH. The hydrated outer layer depends also on the anion present in solution. The transition layer model of the film is proposed to explain the results.

Syntheses and biological activities of 12 N6-substituted adenosine 5'-phosphates and 15 cyclic 3',5'-phosphates are described. Included among these are the cyclic phosphates of the naturally occurring anticodon adjacent modified nucleosides, N6-(delta2-isopentenyl)adenosine and N-(purin-6-ylcarbamoyl)-L-threonine ribonucleoside. Also reported in this paper are the 5'-phosphates and cyclic phosphates of the cytokinins, N6-benzyladenosine, kinetin ribonucleoside, 3-(chloro-trans-2-buten-2-yl)adenosine,6-o-chlorophenylureidopurine ribonucleoside, and 6-allylureidopurine ribonucleoside. The 5'-nucleotides were prepared by direct phosphorylation of the corresponding ribonucleosides with POCl3 and triethyl phosphate. These compounds were converted to the cyclic 3',5'-phosphates by cyclization of the corresponding 5'-nucleotides with dicyclohexylcarbodiimide. Comparison of the cytotoxicity of the ribonucleosides with their 5'-nucleotides and cyclic 3',5'-nucleotides showed that some of the 5'-phosphates and cyclic phosphates were almost as active as the parent nucleosides. The 5'-nucleotides and the cyclic phosphates were more soluble than the parent nucleosides. The cyclic 3',5'-nucleotides were examined as alternate activators of cAMP-dependent protein kinase from beef heart. While all of the analogs studied showed some activity toward this enzyme, several compounds were more effective than cAMP itself. The analogs were also tested as substrates for cyclic 3',5'-nucleotide phosphodiesterase from beef heart. The N6-alkyl-cAMP analogs were poor substrates for the enzyme, while N6-carbamoyl-cAMP derivatives were inert toward this enzyme. These compounds did not inhibit the phosphodiesterase. Some of the cyclic phosphates exhibited marginal effect in the inhibition of glycogen synthesis in skin slices.

The rotational constants A, B, C are functions from the vibrational quantum numbers for the out-of-plane ring bending vibration of 3-methyleneoxetane. Gibson and Harris [1] using microwave spectroscopy had given the dependence between quantum vibrational numbers for the out-of-plane bending mode and rotational constants. In this paper, the agreement between experimental results from the microwave measurements and theoretical ones from the CNDO/2 is analysed. The planarity for the strained four-member ring is confirmed from the information available. The position corresponding to the methylene groups is also predicted from CNDO/2 calculations.

Boron is almost universally used as a p‐type dopant in Si devices. Since this dopant is introduced into the Si lattice under a wide range of diffusion conditions, effects are often observed which appear anomalous because the mechanism of B diffusion is not completely understood. Anomalous effects that have been observed include a concentration‐dependent diffusion coefficient, orientation‐dependent diffusion under oxidizing conditions, and retarded or accelerated diffusion in the presence of n‐type impurities. This paper discusses a model of B diffusion which can be used to explain these observed effects. Data and arguments are presented which show that B diffuses via a monovacancy mechanism when the diffusion is performed in a nonoxidizing ambient. A donor‐type vacancy is responsible which has a presumed energy level of as suggested from the quenching experiments of Elstner and Kamprath. High concentration B diffusions into Si over a 550°C temperature range in neutral ambients result in profile data that fit a normalized universal curve which is a polynomial approximation to the solution of the diffusion equation with concentration‐dependent diffusivity. From this result, useful curves of surface concentration vs. resistivity and junction depth are presented.

The secondary structures of a homologous series of chemically and optically pure protected L-norvaline homo-oligomers, the synthesis and characterization of which is described in the preceding paper, were examined in a number of solvent systems using essentially CD*, and the results compared with those obtained in the isomeric L-valine series. All protected norvaline and valine oligopeptides exist as statistical coil conformations in HFIP and HFA. In TFE, however, BOC-(-L-Val-)7-OMe exists in a β-associated structure in contrast to BOC(-L-Nva)7-OMe. This finding points to the influence of β-branching in directing peptide conformations. The addition of water to solutions of the protected norvaline and valine peptides in TPE forces the higher oligomers to assume intermolecular β-type conformations. The aggregated structures could be disrupted by dilution or heating.

The present paper provides a new useful means of synthesis of 2, 3, 3-trisubstituted phthalimidines. Alkylation of phthalimidines at 3-position has been found to proceed with alkyl halide in liquid ammonia in the presence of potassium amide.

The values of the transition moment of Raman scattering have been calculated according to the formula derived from the vibronic expansion approach. The calculations have been performed for the symmetry coordinates of several small molecules and for the normal vibrations of methane. The electronic wave functions were calculated by the CNDO/2-CI method. The calculated results are large in comparison with the experimental ones. The calculated Raman intensities for the symmetric stretching vibrations were almost all contributed by the term A in the vibronic expansion theory. From the calculated results for the normal vibrations of methane, it was found that the vibronic method used in this work leads to more appropriate values than those obtained from the polarizability theory which was used in the previous paper.