696 research outputs found
Designing Robust Unitary Gates: Application to Concatenated Composite Pulse
We propose a simple formalism to design unitary gates robust against given
systematic errors. This formalism generalizes our previous observation [Y.
Kondo and M. Bando, J. Phys. Soc. Jpn. 80, 054002 (2011)] that vanishing
dynamical phase in some composite gates is essential to suppress amplitude
errors. By employing our formalism, we naturally derive a new composite unitary
gate which can be seen as a concatenation of two known composite unitary
operations. The obtained unitary gate has high fidelity over a wider range of
the error strengths compared to existing composite gates.Comment: 7 pages, 4 figures. Major revision: improved presentation in Sec. 3,
references and appendix adde
Isolation, identification and anti-cancer activity of minor alkaloids from Triclisia subcordata
No abstrac
A Report on the Environmental Impact of the Texas LoanSTAR Program from May 1989 to September 1995
There are a number of factors that influence emission factors. The three major pollutants considered in this analysis are CO2, SO2, and NOX. Emission factors from three different sources were considered for this report. This analysis shows that as of September, 1995, there has been a reduction in emissions of 1.88 million pounds of NOX, 1.19 million pounds of SO2, and 532 million pounds of CO2 through the implementation of energy conservation measures in the Texas LoanSTAR program.The Texas LoanSTAR (Loans to Save Taxes and Resources) program was created by the state of Texas in 1989 to lend money for energy conserving improvements, or retrofits, in public buildings. As of September 1995 the LoanSTAR program is measuring savings for 22 loan sites covering 153 buildings where retrofits have been fully or partially completed. The completed retrofits show $21.1 million in measured savings, which is more than 119% of the energy savings predicted by the energy auditors. This corresponds to 23.9% of the pre-retrofit consumption cost at these sites. Through energy savings, the Texas LoanSTAR program has made a significant contribution towards reducing hazardous environmental emissions
Anthropogenic Noise Changes Arthropod Abundances
Anthropogenic noise is a widespread and growing form of sensory pollution associated with the expansion of human infrastructure. One specific source of constant and intense noise is that produced by compressors used for the extraction and transportation of natural gas. Terrestrial arthropods play a central role in many ecosystems, and given that numerous species rely upon airborne sounds and substrate-borne vibrations in their life histories, we predicted that increased background sound levels or the presence of compressor noise would influence their distributions. In the second largest natural gas field in the United States (San Juan Basin, New Mexico, USA), we assessed differences in the abundances of terrestrial arthropod families and community structure as a function of compressor noise and background sound level. Using pitfall traps, we simultaneously sampled five sites adjacent to well pads that possessed operating compressors, and five alternate, quieter well pad sites that lacked compressors, but were otherwise similar. We found a negative association between sites with compressor noise or higher levels of background sound and the abundance of five arthropod families and one genus, a positive relationship between loud sites and the abundance of one family, and no relationship between noise level or compressor presence and abundance for six families and two genera. Despite these changes, we found no evidence of community turnover as a function of background sound level or site type (compressor and noncompressor). Our results indicate that anthropogenic noise differentially affects the abundances of some arthropod families. These preliminary findings point to a need to determine the direct and indirect mechanisms driving these observed responses. Given the diverse and important ecological functions provided by arthropods, changes in abundances could have ecological implications. Therefore, we recommend the consideration of arthropods in the environmental assessment of noise-producing infrastructure
An exploratory study of information sources and key findings on UK cocaine-related deaths.
Cocaine-related deaths have increased since the early 1990s in Europe, including the UK. Being multi-factorial, they are difficult to define, detect and record. The European Monitoring Centre for Drugs and Drug Addiction commissioned research to: describe trends reported to Special Mortality Registries and General Mortality Registers; provide demographic and drug-use characteristic information of cases; and establish how deaths are identified and classified. A questionnaire was developed and piloted amongst all European Monitoring Centre for Drugs and Drug Addiction Focal Point experts/Special Mortality Registries: 19 (63%) responded; nine countries provided aggregated data. UK General Mortality Registers use cause of death and toxicology to identify cocaine-related deaths. Categorisation is based on International Classification of Diseases codes. Special Mortality Registries use toxicology, autopsy, evidence and cause of death. The cocaine metabolites commonly screened for are: benzoylecgonine, ecgonine methyl ester, cocaethylene and ecgonine. The 2000s saw a generally accelerating upward trend in cases, followed by a decline in 2009. The UK recorded 2700-2900 deaths during 1998-2012. UK Special Mortality Registry data (2005-2009) indicate: 25-44 year-olds account for 74% of deaths; mean age=34 (range 15-81) years; 84% male. Cocaine overdoses account for two-thirds of cases; cocaine alone being mentioned/implicated in 23% in the UK. Opioids are involved in most (58%) cocaine overdose cases
Modular Design via Multiple Anion Chemistry of the High Mobility van der Waals Semiconductor Biâ‚„Oâ‚„SeClâ‚‚
Making new van der Waals materials with electronic or magnetic functionality is a chemical design challenge for the development of two-dimensional nanoelectronic and energy conversion devices. We present the synthesis and properties of the van der Waals material Bi4O4SeCl2, which is a 1:1 superlattice of the structural units present in the van der Waals insulator BiOCl and the three-dimensionally connected semiconductor Bi2O2Se. The presence of three anions gives the new structure both the bridging selenide anion sites that connect pairs of Bi2O2 layers in Bi2O2Se and the terminal chloride sites that produce the van der Waals gap in BiOCl. This retains the electronic properties of Bi2O2Se while reducing the dimensionality of the bonding network connecting the Bi2O2Se units to allow exfoliation of Bi4O4SeCl2 to 1.4 nm height. The superlattice structure is stabilized by the configurational entropy of anion disorder across the terminal and bridging sites. The reduction in connective dimensionality with retention of electronic functionality stems from the expanded anion compositional diversity
A Report on the Environmental Impact of the Texas LoanSTAR Program from May 1989 to September 1995
There are a number of factors that influence emission factors. The three major pollutants considered in this analysis are CO2, SO2, and NOX. Emission factors from three different sources were considered for this report. This analysis shows that as of September, 1995, there has been a reduction in emissions of 1.88 million pounds of NOX, 1.19 million pounds of SO2, and 532 million pounds of CO2 through the implementation of energy conservation measures in the Texas LoanSTAR program.The Texas LoanSTAR (Loans to Save Taxes and Resources) program was created by the state of Texas in 1989 to lend money for energy conserving improvements, or retrofits, in public buildings. As of September 1995 the LoanSTAR program is measuring savings for 22 loan sites covering 153 buildings where retrofits have been fully or partially completed. The completed retrofits show $21.1 million in measured savings, which is more than 119% of the energy savings predicted by the energy auditors. This corresponds to 23.9% of the pre-retrofit consumption cost at these sites. Through energy savings, the Texas LoanSTAR program has made a significant contribution towards reducing hazardous environmental emissions
Steam reforming on transition-metal carbides from density-functional theory
A screening study of the steam reforming reaction (CH_4 + H_2O -> CO + 3H_2)
on early transition-metal carbides (TMC's) is performed by means of
density-functional theory calculations. The set of considered surfaces includes
the alpha-Mo_2C(100) surfaces, the low-index (111) and (100) surfaces of TiC,
VC, and delta-MoC, and the oxygenated alpha-Mo_2C(100) and TMC(111) surfaces.
It is found that carbides provide a wide spectrum of reactivities towards the
steam reforming reaction, from too reactive via suitable to too inert. The
reactivity is discussed in terms of the electronic structure of the clean
surfaces. Two surfaces, the delta-MoC(100) and the oxygen passivated
alpha-Mo_2C(100) surfaces, are identified as promising steam reforming
catalysts. These findings suggest that carbides provide a playground for
reactivity tuning, comparable to the one for pure metals.Comment: 6 pages, 4 figure
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