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The neutron-capture reaction plays a critical role in the synthesis of the elements in stars and is important for societal applications including nuclear power generation and stockpile-stewardship science. However, it is difficult---if not impossible---to directly measure neutron capture cross sections for the exotic, short-lived nuclei that participate in these processes. In this Letter we demonstrate a new technique which can be used to indirectly determine neutron-capture cross sections for exotic systems. This technique makes use of the $(d,p)$ transfer reaction, which has long been used as a tool to study the structure of nuclei. Recent advances in reaction theory, together with data collected using this reaction, enable the determination of neutron-capture cross sections for short-lived nuclei. A benchmark study of the $^{95}\mathrm{Mo}(d,p)$ reaction is presented, which illustrates the approach and provides guidance for future applications of the method with short-lived isotopes produced at rare isotope accelerators.

The evolution of shell structure and the fragility of the benchmark magic numbers is a topic of major interest in nuclear-structure physics. The authors measured the structure-sensitive $g$ factors of states in unstable even-even strontium isotopes, following $\ensuremath{\alpha}$-pickup reactions by krypton beams from a carbon target. The results help elucidate how protons and neutrons contribute to the evolution of nuclear structure in this important mass region where rapid structural changes occur.

Background: Single-particle and collective modes of nuclear excitation compete in the isotopes of the elements ${}_{30}$Zn, ${}_{32}$Ge, ${}_{34}$Se, ${}_{36}$Kr, and ${}_{38}$Sr.Purpose: To study the factors which determine the onset of collectivity in this region.Methods: Data obtained from National Nuclear Data Center compilations supplemented by recent measurements of excitation energies and $B(E2)$ reduced transition probabilities between the low-lying states in these elements were examined. The data were analyzed as a function of the neutron number $N$ as well as the parameter $P={N}_{p}{N}_{n}/({N}_{p}+{N}_{n})$ related to the number of valence protons and neutrons, ${N}_{p}$ and ${N}_{n}$, in the $28\ensuremath{\le}Z,N\ensuremath{\le}50$ shell.Results: The systematics of the data show variations ranging from mostly single-particle to collective excitations.Conclusions: Collectivity sets in when the number of both protons and neutrons lie near the middle of the shell $30\ensuremath{\le}Z,N\ensuremath{\le}50$. Backbends appear in the data showing that particles and holes in the major shell behave differently. The ${2}_{2}^{+}$ states exhibit single particle behavior. The transition probabilities of the ${2}_{2}^{+}$ states in the Kr isotopes differ significantly from the systematics.

Byssochlamys fulva is a mold that produces ascospores which can survive thermal processing and cause spoilage of canned fruit products. The growth of B. fulva was examined in ‘Loring’ and ‘Babygold 6’ peach halves which had been processed in 40° Brix sucrose syrup, removed from cans, and then infected with this organism. Ascospore production and changes in soluble solids, total solids, pH, total acidity, total and water soluble pectin, and texture were determined 2, 4, 8 and 16 days post infection. Results indicated that ascospore production began after 8 days and was not affected by the variety or maturity of the peach. Decreases in soluble and total solids in inoculated peaches after 4 days was attributed to utilization of sucrose and conversion of peach constitutents to volatile components. There was little change in pH and total acidity of the peaches during the growth of the mold. The pectic enzymes secreted by B. fulva resulted in an initial increase in water soluble pectin followed by a decrease in total and water soluble pectins. Textural changes were noted in inoculated peaches as compared to controls. Inoculated mature peach halves of both test varieties softened more quickly than did immature halves.

Selected innovations and advances in electrophotographic printing are reviewed. Technological advances in photoreceptors, imaging techniques, toner development and cleaning, fusing, sensors, and new machine configurations and functions are discussed with respect to their possible applicability to future electrophotographic imaging systems. In general, improvements in print quality and reliability remain the main goals. In specific applications, added functions and an increased range of usable media are highly desired.

Ten strains of Byssochlamys fulva and three strains of B. nivea were cultured in a laboratory medium and tested for their ability to produce patulin. Two strains of B. fulva and all three strains of B. nivea produced the mycotoxin. One strain of B. fulva produced patulin in 11 of 13 processed fruit juices, with greatest amounts being produced in blueberry, red raspberry, and boysenberry juices, whereas no patulin was detected in prune or tomato juices. Grown in Concord grape juice at 18, 25, 30, and 38 degrees C, this strain produced the highest patulin concentration at 18 degrees C after 25 days, whereas biomass production was greatest at 25 and 30 degrees C after 20 and 25 days.

In investigating formation of tyramine and histamine in a model system, it was found that four commercial sausage starter cultures did not exhibit appreciable tyrosine or histidine decarboxylase activity. In addition, other species of Pediococcus cerevisiae and Lactobacillus did not display appreciable decarboxylase activity. Mixtures of P. cerevisiae and Lactobacillus plantarum were also unable to produce significant levels of these amines. One species of Streptococcus tested was able to produce 34.5 μg of tyramine/hour under the assay conditions. When P. cerevisiae and L. plantarum were used as starter cultures to prepare sausages, it was found that this treatment resulted in lower tyramine levels (approximately 200 μ/g) than when the Streptococcus sp. was used as a starter culture (approximately 300 μ/g). However, the use of P. cerevisiae and L. plantarum did not result in a significantly lower tyramine level than when no starter culture was used.

While it has previously been suspected that Byssochlamys spp. may grow in canned fruits and produce the mycotoxin patulin, direct evidence for this occurrence is not available: The effects of different initial static oxygen levels, and temperatures on the formation of patulin by B. nivea in Concord grape juice packed in glass jars was examined. The greatest amount of patulin(0.31 mg/SO ml) was formed after 28 days in jars with a 5.1 cm headspace incubated at 20°C. Patulin was formed more rapidly at 25° and 30°C, but declined in a mounts after reaching maximum values. Cultures of B. fulva and B. nivea produced less patulin in grape juice packed in glass jars with headspaces of 2.5 and 1.3 cm than in glass jars with a 5.1 cm headspace. More favorable conditions were used in this study to produce patulin than would be found in the commercial production of Concord grape juice.

Biologically active amines are normal constituents of many foods and have been found in cheese; sauerkraut; wine; and putrid, aged, or fermented meats. These low molecular weight organic bases do not represent any hazard to individuals unless large quantities are ingested or natural mechanisms for their catabolism are inhibited or genetically deficient. Tyramine, histamine, and phenethylamine, which can arise from enzymatic decarboxylation of the corresponding amino acids, are strongly vasoactive. Histamine, a capillary dilator, produces hypotensive effects while tyramine and phenethylamine cause a rise in blood pressure. Phenethylamine has been implicated in the onset of migraine headache attacks. The occurrence, mechanism of formation, and catabolism of these compounds is reviewed.

Hole‐drift‐mobility measurements are presented for a molecularly doped polymer, p‐diethylaminobenzaldehyde‐diphenyl hydrazone in polycarbonate, over the widest temperature (213–373 K) and electric‐field range (3.3–111 V/μm) yet reported. Use of these data and graphical techniques which we introduce allow us to unambiguously determine for the first time the functional form of the electric field and temperature dependence of the mobility. Consistent with results obtained by others, the observed field dependence cannot be accounted for by any known hopping model. The observed temperature dependence suggests that the activation energy may be temperature dependent.

Polydimethylsiloxane elastomer immersed in DC 200 silicone oil at temperatures of 180–200°C absorbs oil by two concurrent processes, a rapid and reversible diffusion process and a slower, irreversible process resulting from the chemical degradation of the sample. Absorption by diffusion reaches equilibrium in 200 h, and the absorption capacity depends on the amount of curing agent used in the preparation of the elastomer composite. The oil absorbed during this period can be removed by extraction. The absorption capacity is less for the elastomer composites containing silica and decreases linearly with the volume fraction of elastomer in the sample, indicating that only the elastomer absorbs oil. The rate of absorption depends on t1/2 and has a weak temperature dependence. The diffusion coefficients are in the range 10−12 m2/s, and do not seem to be affected by the presence of filler. While the diffusion of oil does not appear to produce chemical changes in the elastomer, the elastomer is gradually destroyed by the slower chemical process, which promotes the absorption of additional amounts of oil.

A survey was conducted to determine the histamine and tyramine contents of a variety of meat products. Histamine was found in all products at concentrations only slightly greater than one would expect from normal physiological amounts found in muscle. Semi-dry sausage products contained an average histamine concentration of 3.59 μg/g compared to an average of 2.87 μg/g in dry sausages. Country-cured hams averaged 1.69 μg histamine/g. Emulsion type products contained slightly less histamine than the fermented sausages. Braunschweiger, an exception, contained 3.6 μg histamine/g but would be expected to contain more histamine than other emulsion-type products because of its liver content. Data indicate that histamine is not formed to an appreciable extent in these meat products under normal processing conditions. Detectable amounts of tyramine were found in 71% of the sausages and in 39% of semi-dry sausages. Tyramine was not detected in country-cured ham. Average tyramine concentrations were 244 and 85.8 μg/g in the dry and semi-dry sausages, respectively. The greatest tyramine concentration found in this study was 1237 μg/g in a Genoa salami. It is apparent that sufficient tyramine can occur in ripened sausages to be troublesome to tyramine-susceptible individuals.

Surface type gear pitting failures were produced on a geared roller test machine and pitting life data were statistically analyzed by a method that accounts for or minimizes the influence of variables determining the fatigue environment. In the geared roller test machine, rollers were mounted on two parallel shafts supported by a hinged upper and lower frame. Power was supplied to the lower shaft and transmitted to the upper shaft via phasing gears. Sliding was controlled by changing the phasing gear ratio or by changing speed. The machine housing served as an oil reservoir. Vibration switches terminated the test when a fatigue pit larger than 1/8 inch in diameter was generated. Larger pits were sometimes generated, depending on test conditions and on multiple origin failures. Statistical analysis of test data demonstrated the sensitivity of contact fatigue to microstructural variations and to changes in the amount of negative sliding when variables determining the operating environment were accounted for or minimized. Decreased pitting life in rollers carburized at high temperatures was primarily attributed to grain growth. Small changes in the amount of retained austenite, microcracks, and oxide type were of secondary importance. Pitting life increased when rollers were reheated after carburizing for grain refinement.

Bisbenzeneiron(II) hexafluorophosphate is made in excellent yield by the reaction of FeCl3, AlCl3, and benzene followed by solvolysis and treatment with aqueous ammonium hexafluorophosphate.