830 research outputs found
Retrofitting Crude Oil Refinery Heat Exchanger Networks to Minimise Fouling While Maximising Heat Recovery
The use of fouling factors in heat exchanger design and the lack of appreciation of fouling in traditional pinch approach has often resulted badly designed crude preheat networks that are expensive to maintain. The development of thermal and pressure drop models for crude oil fouling has allowed its effects to be quantified, so that techno-economic analyses can be performed and various design options compared. Application of these fouling models is carried out on two levels: on the assessment of adding extra area to individual exchangers, and the design of a complete network using the Modified Temperature Field Plot. Application to a refinery case study showed that both at the exchanger and network levels, designing for maximum heat recovery using traditional pinch approach results in the least efficient heat recovery over a time period when fouling occurs
The Perturbative Pole Mass in QCD
It is widely believed that the pole mass of a quark is infrared-finite and
gauge-independent to all orders in perturbation theory. This seems not to have
been proved in the literature. A proof is provided here.Comment: 12 pages REVTeX with 2 figures; archiving published version with note
and references added. If you thought this was proven long ago see
http://www-theory.fnal.gov/people/ask/TeX/mPole
Development and clinical performance of high throughput loop-mediated isothermal amplification for detection of malaria.
BACKGROUND: Accurate and efficient detection of sub-microscopic malaria infections is crucial for enabling rapid treatment and interruption of transmission. Commercially available malaria LAMP kits have excellent diagnostic performance, though throughput is limited by the need to prepare samples individually. Here, we evaluate the clinical performance of a newly developed high throughput (HTP) sample processing system for use in conjunction with the Eiken malaria LAMP kit. METHODS: The HTP system utilised dried blood spots (DBS) and liquid whole blood (WB), with parallel sample processing of 94 samples per run. The system was evaluated using 699 samples of known infection status pre-determined by gold standard nested PCR. RESULTS: The sensitivity and specificity of WB-HTP-LAMP was 98.6% (95% CI, 95.7-100), and 99.7% (95% CI, 99.2-100); sensitivity of DBS-HTP-LAMP was 97.1% (95% CI, 93.1-100), and specificity 100% against PCR. At parasite densities greater or equal to 2 parasites/ÎŒL, WB and DBS HTP-LAMP showed 100% sensitivity and specificity against PCR. At densities less than 2 p/ÎŒL, WB-HTP-LAMP sensitivity was 88.9% (95% CI, 77.1-100) and specificity was 99.7% (95% CI, 99.2-100); sensitivity and specificity of DBS-HTP-LAMP was 77.8% (95% CI, 54.3-99.5) and 100% respectively. CONCLUSIONS: The HTP-LAMP system is a highly sensitive diagnostic test, with the potential to allow large scale population screening in malaria elimination campaigns
Gaussian Wavefunctional Approach in Thermofield Dynamics
The Gaussian wavefunctional approach is developed in thermofield dynamics. We
manufacture thermal vacuum wavefunctional, its creation as well as annihilation
operators,and accordingly thermo-particle excited states. For a
(D+1)-dimensional scalar field system with an arbitrary potential whose Fourier
representation exists in a sense of tempered distributions, we calculate the
finite temperature Gaussian effective potential (FTGEP), one- and
two-thermo-particle-state energies. The zero-temperature limit of each of them
is just the corresponding result in quantum field theory, and the FTGEP can
lead to the same one of each of some concrete models as calculated by the
imaginary time Green function.Comment: the revised version of hep-th/9807025, with one equation being added,
a few sentences rewritten, and some spelling mistakes corrected. 7 page,
Revtex, no figur
Perturbative Expansion around the Gaussian Effective Potential of the Fermion Field Theory
We have extended the perturbative expansion method around the Gaussian
effective action to the fermionic field theory, by taking the 2-dimensional
Gross-Neveu model as an example. We have computed both the zero temperature and
the finite temperature effective potentials of the Gross-Neveu model up to the
first perturbative correction terms, and have found that the critical
temperature, at which dynamically broken symmetry is restored, is significantly
improved for small value of the flavour number.Comment: 14pages, no figures, other comments Typographical errors are
corrected and new references are adde
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