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61.
Coal and gangue (black-gray solid wastes in coal) recognition is vital to avoid waste of resources and pollution of the environment during the coal production. Considering their color/temperature is very close to each other, the traditional visible image and infrared image analyzing method is hard to obtain satisfied recognition efficiency. Therefore, a new idea of the ‘liquid intervention + infrared monitoring’ method was proposed to improve the recognition efficiency. In this article, the coal/gangue recognition experiments with different water temperatures were conducted, and the infrared thermal imager was used to record temperature variation after water intervention. The results show that when the water temperature is lower than the ambient temperature, the temperature difference between coal and gangue reaches the maximum value within 10 s, which is five times that without water intervention. The mean value of temperature difference between coal and gangue shows an approximate linear downward trend with the increasing of water temperature. The results indicate that under the condition of water intervention, it is recommended to choose water with a temperature below the ambient air, which may be a new approach to improve the coal/gangue recognition efficiency under different complex environments in underground coal mines. 相似文献
62.
Dynamics of the tippe top via Routhian reduction 总被引:1,自引:1,他引:0
We consider a tippe top modeled as an eccentric sphere, spinning on a horizontal table and subject to a sliding friction.
Ignoring translational effects, we show that the system is reducible using a Routhian reduction technique. The reduced system
is a two dimensional system of second order differential equations, that allows an elegant and compact way to retrieve the
classification of tippe tops in six groups as proposed in [1] according to the existence and stability type of the steady
states.
相似文献
63.
推出了TC理论的中性PG玻色子与规范玻色子(Z、γ、g)的总耦合拉氏量,计算了t夸克圈对中性PG玻色子衰变宽度的影响.结果表明t夸克圈能有效地增加反常耦合强度,为在实验上寻找PG玻包子提供了理论依据. 相似文献
64.
Greyscale morphology is more efficient and useful for processing greyscale image. It is the extension of binary morphology by use of a min or max operations. Optics is suitable for the implementation of morphological transformations because of its parallelism. However, greyscale morphology with both greyscale images and greyscale structuring elements is difficult to realize threshold decomposition since it does not commute with threshold. We propose a correlation approach for greyscale morphological transformations using area-coding technique to represent the umbra of surfaces of both greyscale image and greyscale structuring element. A primary experiment of greyscale dilation is presented. 相似文献
65.
The [M + 20H](20+)-[M + 12H](12+) charge states of native and reduced porcine elastase, a 25.9 kDa serine protease, were subjected to collisional activation in a quadrupole ion trap. For most charge states, ion parking was used to increase the number of parent ions over that yielded directly by electrospray. Ion-ion proton transfer reactions were used to reduce product ion charge states largely to +1 to simplify spectral interpretation. Both forms of the protein show charge state dependent fragmentation behavior. The native protein, which contains four disulfide linkages, shows almost no evidence for fragmentation within the regions of the protein linked by disulfide bonds. However, at the lowest charge states studied, evidence for cleavage of a least one of the disulfide bonds was evident in the appearance of a c-type ion. The highest charge states of native elastase showed several prominent cleavages C-terminal to valine residues. As the charge state decreased, however, preferential cleavages at acidic amino acid residues became important. The reduced form of the protein did not show particularly prominent cleavages at valine residues. However, many of the same preferential cleavages at acidic amino acid residues noted for the native protein were also observed in the same charge states of the reduced protein. The reduced protein also showed additional cleavages from regions of the protein that are ordinarily protected by disulfide linkages in the native form. 相似文献
66.
67.
李善吉 《广东微量元素科学》2012,19(8):67-69
高分子实验教学是培养高分子应用型人才重要的实践教学环节。针对应用型人才的培养,根据该校的实验情况,对高分子化学实验教学的改革进行了初步探讨。 相似文献
68.
The top triangle moose (TTM) model, which can be seen as the deconstructed version of the topcolor-assisted technicolor (TC2) model, predicts the existence of the charged top-pions πt± in low energy spectrum. In the context of this model, we consider photoproduction of πt± via the subprocesses γb→tπ-and γ→πt+ at the large hadron-electron collider (LHeC), in which high energy photon beams are generated by using the Compton backscatting method. We find that, as long as the charged top-pions are not too heavy, they can be abundantly produced via γb collision. 相似文献
69.
Rotationalenergytransfer(RET)isoneofthemostcommonandsimplestinelasticmolecularcollisionalprocesses,anditreflectstheanisotropyoftheinteractionpotentialofthecouplingbetweentheorbitalmotionofthemoleculewithrespecttotheothercollisionpartnerandtherotationalmotion.Also,knowledgeoftheseenergytransferratesarealsoimportantinotherareas,suchaslaserdesignofchemicallaser,etc.Dixon','andAlwahabi'hadstudiedinelasticcollisionsofNH,(A'A,)inaflowingsystem.Butsincetheresultswerenotobtainedundersinglecollision… 相似文献
70.