1,832 research outputs found
The Ursinus Weekly, December 19, 1974
SFARC: Alive and very well ⢠The Great Wismer rip-off ⢠Letters to the editor ⢠Two U.C. men named to boards ⢠Basketball begins ⢠Doom or defense? ⢠Grappling goings-on ⢠U.C. tuition increase called modest ⢠An open letter to the student body of Ursinus ⢠Alumni publish ⢠The Ursinus Weaklyhttps://digitalcommons.ursinus.edu/weekly/1028/thumbnail.jp
Measuring denitrification and the NO:(NO + N) emission ratio from terrestrial soils
Denitrification, a significant pathway of reactive N-loss from terrestrial soils, impacts on agricultural production and the environment. Net production and emission of the denitrification product nitrous oxide (NO) is readily quantifiable, but measuring denitrification\u27s final product, dinitrogen (N), against a high atmospheric background remains challenging. This review examines methods quantifying both N and NO emissions, based on inhibitors, helium/O atmosphere exchange, and isotopes. These methods are evaluated regarding their capability to account for pathways of N and NO production and we suggest quality parameters for measuring denitrification from controlled environments to the field scale. Our appraisal shows that method combinations, together with real-time monitoring and soil-gas diffusivity modelling, have the potential to significantly improve our quantitative understanding for denitrification from upland soils. Requirements for instrumentation and experimental setups however highlight the need to develop more mobile and easily accessible field methods to constrain denitrification from terrestrial soils across scales
the path to silicon-singlet fission heterojunction devices
Singlet exciton fission is an exciton multiplication process that occurs in certain organic materials, converting the energy of single highly-energetic photons into pairs of triplet excitons. This could be used to boost the conversion efficiency of crystalline silicon solar cells by creating photocurrent from energy that is usually lost to thermalisation. An appealing method of implementing singlet fission with crystalline silicon is to incorporate singlet fission media directly into a crystalline silicon device. To this end, we developed a solar cell that pairs the electron-selective contact of a high-efficiency silicon heterojunction cell with an organic singlet fission material, tetracene, and a PEDOT:PSS hole extraction layer. Tetracene and n-type crystalline silicon meet in a direct organicâinorganic heterojunction. In this concept the tetracene layer selectively absorbs blue-green light, generating triplet pairs that can dissociate or resonantly transfer at the organo-silicon interface, while lower-energy light is transmitted to the silicon absorber. UV photoemission measurements of the organicâinorganic interface showed an energy level alignment conducive to selective hole extraction from silicon by the organic layer. This was borne out by currentâvoltage measurements of devices subsequently produced. In these devices, the silicon substrate remained well-passivated beneath the tetracene thin film. Light absorption in the tetracene layer created a net reduction in current for the solar cell, but optical modelling of the external quantum efficiency spectrum suggested a small photocurrent contribution from the layer. This is a promising first result for the direct heterojunction approach to singlet fission on crystalline silicon
Introducing discrete frequency infrared technology for high-throughput biofluid screening
Accurate early diagnosis is critical to patient survival, management and quality of life. Biofluids are key to early diagnosis due to their ease of collection and intimate involvement in human function. Large-scale mid-IR imaging of dried fluid deposits offers a high-throughput molecular analysis paradigm for the biomedical laboratory. The exciting advent of tuneable quantum cascade lasers allows for the collection of discrete frequency infrared data enabling clinically relevant timescales. By scanning targeted frequencies spectral quality, reproducibility and diagnostic potential can be maintained while significantly reducing acquisition time and processing requirements, sampling 16 serum spots with 0.6, 5.1 and 15% relative standard deviation (RSD) for 199, 14 and 9 discrete frequencies respectively. We use this reproducible methodology to show proof of concept rapid diagnostics; 40 unique dried liquid biopsies from brain, breast, lung and skin cancer patients were classified in 2.4 cumulative seconds against 10 non-cancer controls with accuracies of up to 90%
The Ursinus Weekly, October 3, 1974
Statistics prove rumor unfounded ⢠WRUC FM hits the air ⢠New chaplain brings new ideas to U.C. ⢠Musical forum presented by Mme. Agi Jambor ⢠Dr. Williamson authors new study of Corinthians ⢠Editorial ⢠Pages from Ursinus past ⢠Alumni corner: Assurance to insurance ⢠Summer in the city ⢠Letter from London ⢠S.F.A.R.C. and you ⢠Assistant Deans of Men and Women appointed ⢠Festival help needed ⢠Slow boat to China ⢠Harriers sweep Drew and Eastern ⢠The Spirit of the 76ers ⢠Women\u27s hockey season opens ⢠Why Bears?https://digitalcommons.ursinus.edu/weekly/1020/thumbnail.jp
AMI observations of Lynds Dark Nebulae: further evidence for anomalous cm-wave emission
Observations at 14.2 to 17.9 GHz made with the AMI Small Array towards
fourteen Lynds Dark Nebulae with a resolution of 2' are reported. These sources
are selected from the SCUBA observations of Visser et al. (2001) as small
angular diameter clouds well matched to the synthesized beam of the AMI Small
Array. Comparison of the AMI observations with radio observations at lower
frequencies with matched uv-plane coverage is made, in order to search for any
anomalous excess emission which can be attributed to spinning dust. Possible
emission from spinning dust is identified as a source within a 2' radius of the
Scuba position of the Lynds dark nebula, exhibiting an excess with respect to
lower frequency radio emission. We find five sources which show a possible
spinning dust component in their spectra. These sources have rising spectral
indices in the frequency range 14.2--17.9 GHz. Of these five one has already
been reported, L1111, we report one new definite detection, L675, and three new
probable detections (L944, L1103 and L1246). The relative certainty of these
detections is assessed on the basis of three criteria: the extent of the
emission, the coincidence of the emission with the Scuba position and the
likelihood of alternative explanations for the excess. Extended microwave
emission makes the likelihood of the anomalous emission arising as a
consequence of a radio counterpart to a protostar or a proto-planetary disk
unlikely. We use a 2' radius in order to be consistent with the IRAS
identifications of dark nebulae (Parker 1988), and our third criterion is used
in the case of L1103 where a high flux density at 850 microns relative to the
FIR data suggests a more complicated emission spectrum.Comment: submitted MNRA
The Ursinus Weekly, February 14, 1974
Week-long festival of arts slated to begin February 22 ⢠Ursinus, at mid-winter, continues coping with problems of energy conservation ⢠Forums set for semester ⢠ProTheatre to present evening of avant-garde ⢠Villanova University to sponsor tenth law review symposium ⢠Editorial: The Myrin follies; Situation wanted: Hero ⢠First semester Deanâs List ⢠Letters to the editor: Union anniversary; Madison Avenue\u27s effect ⢠Student teachers respond to experiences in area schools ⢠SFARC News ⢠Film Review: The Exorcist ⢠Alumni Corner: Mike Hunter: Society drop-in ⢠De-horn the Rams! ⢠Jazz: Thad Jones, Mel Lewis ⢠USGA holds elections, makes amendments and forms committees ⢠9-5 and still alive!https://digitalcommons.ursinus.edu/weekly/1009/thumbnail.jp
The Ursinus Weekly, October 25, 1973
Fraternities select homecoming candidates; Students will vote for favorites today ⢠Ursinus will make record books with giant banana split ⢠Chemistry department gets $3000 grant ⢠Longer hours suggested for noisy Myrin library ⢠Volunteer service program begins work; Ken-Crest Center will be first effort ⢠Editorial: Minority student speaks out on biological overpopulation ⢠Faculty portrait: Mrs. Mary Anne Clausen ⢠The Big Game ⢠Alumni corner ⢠Letter to the editor: Tradition and the individual ⢠Lord Caradon, U.N. Representative, speaks on âobligation of optimismâ ⢠Shaw-Bernard art exhibit opens today ⢠Placement office helpful for job-hunting seniors ⢠Bearettes sweep south and extend wins to nine ⢠Harriers return to winning ways ⢠Sing wins tournament ⢠Soccer teamâs record now stands at 3-3-1 ⢠Ursinus Bears win first game of the seasonhttps://digitalcommons.ursinus.edu/weekly/1003/thumbnail.jp
The Ursinus Weekly, February 21, 1974
Theatre production will start week of arts festivities ⢠Service stations in Collegeville reflect national trends in current fuel shortage ⢠Whitians name nineteen new members to group ⢠Freshman class discusses donations, cut system ⢠Open house policy to continue this semester ⢠Strategy is key word in new club ⢠Editorials: Solzhenitsyn: One man in the world; Behind the green porn ⢠Letter to the editor: Faculty flops ⢠Forum Review: Dr. Joseph Feldmeier ⢠Alumni Corner: Dr. Jacob Shade ⢠In concert: Yes, even closer to the edge ⢠The Zodiac: Will Ursinus survive the Aquarian age? ⢠Little known Bill of Rights, responsibilities makes its appearance after three years ⢠What can you say? ⢠Grapplers close season; boast 3 shut-outs in rowhttps://digitalcommons.ursinus.edu/weekly/1010/thumbnail.jp
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