Direct Photoelectric Spectrochemical Determination of Exchangeble Bases of Soil

It is well recognized in the field of soil science that a knowledge of the amounts and relative proportions of the exchangeable cations in the soil is indispensable in studies dealing with the chemical and physical behavior of soil or with soil fertility. While the need for more rapid methods permitting analysis of large numbers of soil samples has resulted in the development of rapid microchemical methods (11, 12) and spectrochemical procedures (5, 6, 10), the analytical procedures are time-consuming and hampered by the wide range of concentrations among the constituents. The desirability of greater rapidity and simplicity of analysis without a corresponding impairment of accuracy and precision has led to this investigation of direct photoelectric measurements of spectral radiations as an analytical procedure for the determination of the exchangeable cations of soils

An instrument for internal standard flame photometry and its application to the determination of calcium in the rare earths

Details are given for simple modifications of a laboratory monochromator so that selected internal standard line pairs from flame spectra may be isolated and measured simultaneoualy with a multiplier phototube differential photometer. The basic design is applicable to most spectrometers or spectrographs. An atomizing system with provisions for sample recycling and recovery is also described. This equipment has been applied to the determination of calcium in the rare earths in the concentration range of 0.025 to 2.5%. Average deviation for a series of repeated determinations at various concentrations is about plus or minus 1.5%

Low-Energy Proton Testing Methodology

Use of low-energy protons and high-energy light ions is becoming necessary to investigate current-generation SEU thresholds. Systematic errors can dominate measurements made with low-energy protons. Range and energy straggling contribute to systematic error. Low-energy proton testing is not a step-and-repeat process. Low-energy protons and high-energy light ions can be used to measure SEU cross section of single sensitive features; important for simulation

Comparative genome and transcriptome analyses of the social amoeba Acytostelium subglobosum that accomplishes multicellular development without germ-soma differentiation

Background Social amoebae are lower eukaryotes that inhabit the soil. They are characterized by the construction of a starvation-induced multicellular fruiting body with a spore ball and supportive stalk. In most species, the stalk is filled with motile stalk cells, as represented by the model organism Dictyostelium discoideum, whose developmental mechanisms have been well characterized. However, in the genus Acytostelium, the stalk is acellular and all aggregated cells become spores. Phylogenetic analyses have shown that it is not an ancestral genus but has lost the ability to undergo cell differentiation. Results We performed genome and transcriptome analyses of Acytostelium subglobosum and compared our findings to other available dictyostelid genome data. Although A. subglobosum adopts a qualitatively different developmental program from other dictyostelids, its gene repertoire was largely conserved. Yet, families of polyketide synthase and extracellular matrix proteins have not expanded and a serine protease and ABC transporter B family gene, tagA, and a few other developmental genes are missing in the A. subglobosum lineage. Temporal gene expression patterns are astonishingly dissimilar from those of D. discoideum, and only a limited fraction of the ortholog pairs shared the same expression patterns, so that some signaling cascades for development seem to be disabled in A. subglobosum. Conclusions The absence of the ability to undergo cell differentiation in Acytostelium is accompanied by a small change in coding potential and extensive alterations in gene expression patterns

Low energy packed tower and caustic recovery for direct capture of CO2 from air

We used a 6.5 m tall packed tower prototype to study the capturing rate of CO2 from air. The tower was operated at a pressure drop of less than 27 pa in the packing at 0.7m/sec air speed with a counter current flow mode and with NaOH or KOH solution as the absorbent. The tower consumed an average of ~30 kJe per mole CO2. We found that via an intermittent operation with a 5% duty cycle, the fluid pumping work reduced by 90%. A novel process for removing carbonates ions from alkaline solutions based on titanate compounds is compared to the traditional lime cycle for the caustic recovery. The titanate process reduces the high-grade heat requirement by ~50%. The results from experimental data of leaching andprecipitation test support process design of the titanate cycle. In this paper, we also present the chemical process design