Vibrational analysis of high-energy compounds: 1-nitroso-3,3-dinitroazetidine

Abstract

Infrared spectra were obtained and normal coordinate calculations were made for 1-nitroso-3,3-dinitroazetidine (NO-DNAZ) in order to make assignments of the infrared bands to the appropriate normal modes of vibration. Only one stable conformation was found by semi-empirical molecular orbital calculations. Appropriate force constants that had been obtained for TNAZ were used as starting values for NO-DNAZ. The transferability of the force constants was quite good, so they should be useful in calculations for other dinitroazetidines. Force constant refinements resulted in calculated vibrational wavenumbers that differed from observed values by an average of only 1.9 cm^?1.     

Nickel stimulation of anaerobic digestion

An acetate-enriched methanogenic culture was assayed for nutritional stimulation by nickel in combination with other inorganic and organic nutrients, i.e. iron, cobalt, yeast extract, riboflavin and vitamin B₁₂. Acetate was automatically maintained at 2–3 g l⁻¹ by a pH Stat system so that substrate was not limiting. In the absence of nickel, the specific acetate utilization rates were in the range of 2–4.6 g acetate g⁻¹ VSS day⁻¹. In the presence of nickel, this rate was as high as 10 and when both nickel and yeast extract were supplemented this rate temporarily increased to 12–15 g acetate g⁻¹ VSS day⁻¹ . The maximum acetate utilization rate was observed to be 51 g l⁻¹ day⁻¹ as compared to 3.3 g l⁻¹ day⁻¹ for conventional high-rate digestion. Daily phosphate additions were required to sustain these high acetate utilization rates. An acetate utilization rate of 20–30 g l⁻¹ day⁻¹ was maintained for over 25 days. Microscopic examination of the culture revealed a predominance of a sarcina whenever stimulation was noted.     

Phospholpid studies of marine organisms: 2.1 Phospholipids,phospholipid-bound fatty acids and free sterols of the spongeAplysina fistularis (Pallas) formafulva (Pallas) (=Verongia thiona)2. Isolation and structure elucidation of unprecedented branched fatty acids

The free sterols and phospholipids of the demospongeAplysina fistularis were isolated and analyzed. The free sterols consisted mainly of the unusual 26-methylated sterols aplysterol (53%) and 24(28)-dehydroaplysterol (7%) together with 7 commonly occurring sterods. The major phospholipids were phosphatidylcholine, phosphatidylglycerol, phosphatidylinositol, phosphatidylethanolamine, phosphatidylserine and diphosphatidylglycerol. The major fatty acyl components of the phospholipids consisted of 85% C₁₄−C₂₀ acids, including the unprecedented 2,6,10-trimethyl-5-tetradecenoic acid and 11-methyloctadecanoic acid. The remaining 15% were C₂₇−C₃₀ demospongic acids, including 2 novel acids tentatively assigned the structures 5,9,23-octacosatrienoic acid and 5,9,23-nonacosatrienoic acid, and 3 novel acids proven to be 5,9,21-octacosatrienoic acid, Z,Z-20-methyl-5,9-hexacosadienoic acid and Z,Z-22-methyl-5,9-octacosadienoic acid. The biosyntheses of the novel demospongic acids are proposed to occur by chain elongation of monoenoic or branched precursors followed by desaturation. The large quantities of typically bacterial phospholipids and fatty acids found implied the presence of bacteria in the sponge, in agreement with microscopic studies. Analysis of the phospholipid-bound fatty acids in a sponge cell-enriched fraction indicated that the demospongic acids, including the 2 branched structures, were the major acids of the sponge cells. The presence inA. fistularis of demospongic acids containing membrane disordering groups—methyl branches or double bonds—on the ω7 carbon is proposed to be due to the need by the sponge for membranes possessing fluidity near the middle of the phospholipid bilayer. It is also proposed that the C₂₆ methyl group of aplysterol causes disordering of the phospholipid bilayer in the same region, and thus also evolved in response to this need. For part 1, see ref. 1. Phylum porifera, class demospongia, subclass ceractinomorpha, order verongida, family aplysinidae (2). Formerly known asVerongia thiona de Laubenfels. Major diagnostic fragments from peak 23:M⁺ 471 (2.9%); m/z 442 (C₂₆, 0.2%); m/z 428 (C₂₅, 0.2%); m/z 414 (C₂₄, 0.1%); m/z 400 (C₂₃, 0.3%); (absence of C₂₂ peak); m/z 374 (C₂₁, 0.2%); m/z 360 (C₂₀, 0.2%); m/z 234 (C₁₁, 1.0%); m/z 220 (C₁₀, 0.7%); m/z 206 (C₉, 0.5%); m/z 194 (C₈, 0.4%); m/z 180 (C₇, 24.9%); m/z 166 (C₆, 1.2%); m/z 152 (C₅, 0.8%); m/z 140 (C₄, 1.3%); m/z 126 (C₃, 18.7%). Major diagnostic fragments from peak 25:M⁺ 485 (0.9%); m/z 456 (C₂₇, 0.1%); (absence of C₂₆, C₂₅ peaks); m/z 414 (C₂₄, 0.3%); m/z 400 (C₂₃, 0.1%); m/z 402 (C₂₃, 0.1%); (absence of C₂₂ peak); m/z 374 (C₂₁, 0.1%); m/z 360 (C₂₀, 0.1%); m/z 234 (C₁₁, 0.5%); m/z 220 (C₁₀, 0.3%); m/z 206 (C₉, 0.1%); m/z 194 (C₈, 0.2%); m/z 180 (C₇, 18.0%); m/z 166 (C₆); m/z 152 (C₅), m/z 140 (C₄); m/z 126 (C₃, 15.0%).     

"An exercise in mega-silliness": Reply.

Replies to H. J. Eysenck's (1978) criticisms of M. L. Smith and G. V. Glass's (see record 1978-10341-001) meta-analysis of psychotherapy outcome studies. Eysenck's rejection of any evidence supporting the effectiveness of psychotherapy is disputed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

A Review of Pinealectomy-Induced Melatonin-Deficient Animal Models for the Study of Etiopathogenesis of Adolescent Idiopathic Scoliosis

Adolescent idiopathic scoliosis (AIS) is a common orthopedic disorder of unknown etiology and pathogenesis. Melatonin and melatonin pathway dysfunction has been widely suspected to play an important role in the pathogenesis. Many different types of animal models have been developed to induce experimental scoliosis mimicking the pathoanatomical features of idiopathic scoliosis in human. The scoliosis deformity was believed to be induced by pinealectomy and mediated through the resulting melatonin-deficiency. However, the lack of upright mechanical spinal loading and inherent rotational instability of the curvature render the similarity of these models to the human counterparts questionable. Different concerns have been raised challenging the scientific validity and limitations of each model. The objectives of this review follow the logical need to re-examine and compare the relevance and appropriateness of each of the animal models that have been used for studying the etiopathogenesis of adolescent idiopathic scoliosis in human in the past 15 to 20 years.     

振动时效中结构动态参数变化机理的探讨

本文探讨在振动时效中，金属材料的位错密度和晶格扭曲程度对结构动态参数的影响机理．即含有残余应力的构件，在振动时效期间，晶格扭曲程度和位错密度变化的结果是金属材料内部发生一定的塑性变形和微塑性变形，降低了残余应力；同时，材料结构的阻尼减小，刚度降低，最终导致结构的动态参数发生变化     

High-performance poly(butylene oxide)/poly (ethylene oxide) block copolymer surfactants for the preparation of water-in-oil high internal phase emulsions

High-performance surfactants have been developed for the preparation of water-in-oil high internal phase emulsions (HIPE), particularly for the preparation of polymerized HIPE foams. High-efficiency surfactants with poly(butylene oxide)/poly(ethylene oxide) (BO/EO) block copolymer backbones have been developed that can stabilize an HIPE through polymerization at concentrations as low as 0.006 wt% based on total emulsion weight. Polymerizable versions have been developed that bind into the polymeric foam backbone. BO/EO block copolymer surfactants also allow preparation of polymerized HIPE foams without salt in the aqueous phase. HIPE with the BO/EO surfactants have been prepared at room temperature and polymerized at temperatures exceeding 90°C. By minimizing the required amount of surfactant, allowing the surfactant to react during HIPE polymerizations, eliminating the need for salt, and stabilizing over a broad range of temperatures, BO/EO block copolymer surfactants have demonstrated their place as high-performance HIPE surfactants.     

Polyphenylenepyridyl dendrimers as stabilizing and controlling agents for CdS nanoparticle formation

Semiconductor nanoparticles (NPs) are being actively explored for applications in medical diagnostics and therapy and numerous electronic devices including solar cells. In this paper we demonstrate the influence of the third generation rigid polyphenylenepyridyl dendrimers (PPPDs) of a different architecture on the formation of well-defined CdS NPs. A high temperature approach to the synthesis of novel CdS/PPPD nanocomposites is feasible due to the high thermal stability of PPPDs. The PPPD architecture affects the CdS NP formation: larger NPs are obtained in the presence of dendrimers with 1,3,5-triphenylbenzene cores compared to those with tetrakis(4-ethynylphen-1-yl)methane cores. The reaction conditions such as concentrations of PPPDs and NP precursors and the temperature regime also influence the CdS NP sizes. For the first time, we elucidated a mechanism of CdS NP formation in a non-coordinating solvent through the CdO redispersion in the presence of PPPDs. Interesting optical properties of these CdS/PPPD nanocomposites make them promising candidates for imaging applications.