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In order to establish a comprehensive exergy consumption evaluation system for crude oil pipeline transportation system, this paper proposed the definition and calculation method of unavoidable exergy loss based on the exergy analysis method and basic process of pipeline transportation. Then combined with the exergy flow classification, the exergy consumption index set was established and selected with correlation coefficient method. Furthermore, the exergy consumption evaluation index system was established including four hierarchies of object, intensity, efficiency and target using analytic hierarchy process and the weight of each part was calculated. Finally by means of all the exergy consumption indexes, the status of using energy was analyzed and evaluated. The analysis results showed that optimizing the transportation amount and temperature, energy efficiency could be improved. The evaluation system of exergy consumption established in this paper could improve operation efficiency and reduce energy consumption.

Laser-induced breakdown spectroscopy was used to determine the relationship between the spectral line intensity and surface hardness of 3D printed 18Ni300 maraging steel. Research found that there is a linear relationship between the spectral intensity ratio of ion line to atomic line and the surface hardness of the samples. This linear relationship is closely related to the selected elements and spectral lines. The weak self-absorption spectrum of minor elements can obtain a better linear relationship. We study the effect of the number of laser pulses on the linear relationship. The results show that the ideal results can be obtained by using 100 pulses, which can minimize the damage to the sample.

Background Many studies have confirmed that “in situ ischemia postconditioning” (ISPostC) and “remote ischemic postconditioning” (RIPostC) can reduce cerebral ischemia/reperfusion injury, but there is no comparison was made on the consistency of neuroprotection in ISPostC and RIPostC to different ischemic duration and number of cycles. New method We used a transient middle cerebral artery occlusion model to compare the neuroprotection of ISPostC and RIPostC. We conducted ISPostC and RIPostC via brief and repeated MCA and Femoral artery occlusion followed by different ischemic duration and number of cycles. Infarct volume, brain edema, Neurological deficit scores and Apoptosis were evaluated. Results First, the ISPostC with three cycles of 10-s occlusion/30-s release of both carotid arteries and the RIPostC with three cycles of 10-min occlusion/10-min release of the left and right femoral arteries can obviously reduce cerebral infarction size, brain edema, apoptosis, and improve behavioral deficits than other approaches. Second, three cycles of ischemia/reperfusion may be the best for RIPostC. Comparison with existing method(s) In this paper, we compared different ischemic duration and frequency of ISPostC and RIPostC models to determine the best method. This conclusion helps to unify the experimental methods. Conclusions Different ischemic duration and frequency of ischemic postconditioning affect neuroprotection. three cycles of 10-s occlusion/30-s release of both carotid arteries and three cycles of 10-min occlusion/10-min release of both femoral arteries could be the first choice to study mechanisms of ischemic postconditioning and be conducive to the unification of research results.

The newly-built Compton suppression system at the HL-2A tokamak works in a harsh fusion neutron field especially when the second neutral beam injection system is put into application. The present paper performed Geant4 simulations to study the influences of fusion neutrons on Compton suppressed γ-spectrum analyses. The simulation data show that the influence of fusion neutrons on suppressed γ-spectrum shape is limited, while the influence on detection efficiencies is considerable. Consequently, the changes of detection efficiencies caused by the coexisting neutrons must be taken into account in the subsequent γ-spectrum analyses. Hence, the empirical formulas of γ-ray detection efficiencies of the Compton suppression system, which had considered the influences of fusion neutrons, were put forward and then applied to unfold the experimental γ-spectra. This work lays a superior foundation for the further analyses of the Compton suppressed γ-spectra at the HL-2A tokamak.

The plasma facing component in HL-2A has been damaged seriously after disruption, and for this reason its operation is suspended for maintenance. The experimental phenomena and plasma configurations, calculated by the current filament code (CF-code) using the plasma parameters measured by diagnostics and the signals of the magnetic probes, confirm that the first wall is damaged by the synergetic effects of runaway electrons and disruption induced by a vertical displacement event (VDE). When the plasma column is displaced upward/downward, the strong runaway electrons normally hit the baffle plate of the MP3 or MP1 coil in the upper and lower divertor during the disruption, causing the baffle plates to be holed and wrinkled by the energetic runaway current, and water (for cooling or heating the baffle plates) to leak into the vacuum vessel. Another disastrous consequence is that bellows underlying the baffle plate and outside the coil of MP3 for connecting two segments of the jacket casing pipe are punctured by arcing. The arc may be part of the halo current that forms a complete circuit. The experimental phenomena are indirect but compelling evidence for the existence of a halo current during the disruption and VDE, though the halo current has not been measured by the diagnostics in the HL-2A tokamak.

Absolutely calibrated measurements of the neutron yields which need to cover both D-D and D-T phase of the international thermal-nuclear experimental reactor (ITER) are important for the evaluation of fusion power and fusion gain Q in D-D and D-T operations. This paper describes the in-situ calibration techniques and methods, the neutron sources including 252Cf and neutron generator for calibration, the preliminary accuracy assessment and the error analyses. In addition, some difficult problems regarding the in situ calibration for the neutron flux monitor (NFM) on ITER are presented and discussed.

Neutron flux monitor (NFM) as an important diagnostic sub-system in ITER (international thermonuclear experimental reactor) provides a global neutron source intensity, fusion power and neutron flux in real time. Three types of neutron flux monitor assemblies with different sensitivities and shielding materials have been designed. Through MCNP (Mante-Carlo neutral particle transport code) calculations, this extended system of NFM can detect the neutron flux in a range of 104 n/(cm2?s) to 1014 n/(cm2?s). It is capable of providing accurate neutron yield measurements for all operational modes encountered in the ITER experiments including the in-situ calibration. Combining both the counting mode and Campbelling (MSV; Mean Square Voltage) mode in the signal processing units, the requirement of the dynamic range (107) for these NFMs and time resolution (1 ms) can be met. Based on a uncertainty analysis, the estimated absolute measurement accuracies of the total fusion neutron yield can reach the required 10% level in both the early stage of the DD-phase and the full power DT operation mode. In the advanced DD-phase, the absolute measurement accuracy would be better than 20%.

Two high performance silicon drift detectors (SDD) are installed at the equatorial port with z = 0 and z = -16.4 cm on HL-2A tokamak, respectively These SDDs combine with the new and non-conventional software pulse height analyser (SPHA) successfully developed more recently by us to measure the time evolution of soft x-rays spectra, the thermal and superthermal electron temperatures. The high-quality three-dimensional figure of time evolution for soft x-rays energy spectra is easily obtained by combination of a new SPHA and computer. Therefore, the measurement accuracies and the time resolutions of thermal and superthermal electron temperatures are also improved. The enhancement phenomenon of superthermal electron during electron cyclotron resonance heating (ECRH) can be explained by the combination of superthermal electron avalanche theory and experimental parameters.

A special neutron diagnostic system is proposed that facilitates the measurement of neutron fluxes and spectra in the neutronics and tritium production-test blanket module (NT-TBM) without interrupting the operation of the International Thermal-nuclear Experimental Reactor (ITER), for studying the multiplication rate in the neutron multiplier and breeding ratio of tritium in the breeder. This system includes an encapsulated foil activation system, micro-fission chamber detectors (MFC), and a compact neutron spectrometer using a natural diamond detector (NDD). A helium coolant loop with a reasonable diameter is designed carefully for every measurement channel that ensures that the neutron detectors and preamplifiers would work well under a high temperature scenario and that the filling rates of the neutron multiplier (beryllium pebble) and tritium breeder material (Li4SiO4) would not decrease excessively (the expected value≥80%) due to the dimensions of the helium coolant loop.

Brain-derived neurotrophic factor precusor (proBDNF) is present in many regions of the central nerve system (CNS) and is released in cultured cortical neurons and at hippocampal aynapses. ProBDNF c...