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991.
992.
鄂北地区气测现场解释评价研究 总被引:2,自引:1,他引:1
鄂尔多斯盆地鄂北地区现场气测录井由于受多种因素影响,解释符合率相对较低。针对这一问题,在探讨影响气测录井显示因素、识别气测异常的基础上,分析了消除影响因素的途径和校正公式,建立了随钻全烃与全脱全烃的关系式,论述了地面和地层含气量计算方法。在初步评价气显示性质条件下,经统计分析得出了应用4参数——峰面积、校正全烃值、全烃计算值和地层含气量加权分值的解释评价标准,为鄂北地区气测录井解释评价和产能的初步预测探索了一种新模式,不但解决了鄂北地区气测解释符合率低的问题,而且对于深入开展气测录井参数与油气解释评价研究具有一定的参考意义。 相似文献
993.
分析了高校校园中水回用的必要性,对位于市区和郊区新建高校提出了有针对性的校园中水回用工艺,并对中水回用项目的效益进行了探讨. 相似文献
994.
金属矿山深热矿井气温的预测计算是一个难题,本文探讨了应用灰色系统预测理论来解决这一难题的新途径,并通过实例验证了该方法的可行性和有效性。 相似文献
995.
T. Kawakami Y. Koide N. Teraguchi Y. Tomomura A. Suzuki Masanori Murakami 《Journal of Electronic Materials》1998,27(8):929-935
In order to prepare low resistance ohmic contacts to p-ZnSn by the “deposition and annealing (DA)” technique which has been
extensively used for GaAs and Si-based devices, formation of a heavily doped layer by the p-ZnSe/metal reaction is required.
For p-ZnSe/Ni contacts, Ni and Se reacted preferentially at the ZnSe/Ni interface upon annealing at temperatures higher than
250°C. However, capacitance-voltage measurements showed that the net acceptor concentration (NA-ND) close to the p-ZnSe/Ni interface was reduced upon the Ni/ZnSe reaction, resulting in high contact resistance. For p-ZnSe/Au
contacts, neither Au/ZnSe reaction nor reduction of the acceptor concentration were observed after annealing at temperatures
lower than 300°C. This indicates that although the metal/p-ZnSe reaction is mandatory to prepare a heavily doped layer, the
reaction induced an increase in the compensation donors in the p-ZnSe substrate. In order to increase the acceptor concentration
in the vicinity of the p-ZnSe/metal interface through diffusion from the contact materials, Li or O which was reported to
play the role of an acceptor in ZnSe was deposited with a contact metal and annealed at elevated temperatures. Ni or Ag was
selected as the contact metal, because these metals were expected to enhance Li or O doping by reacting with ZnSe. However,
the current density-voltage characteristics of the Li(N)/Ni and Ag(O) contacts exhibited rectifying behavior, and the contact
resistances increased with increasing annealing temperature. The present results indicated that, even though the acceptor
concentration in the p-ZnSe substrate increased by diffusion of the dopants from the contact elements, an increment of the
compensation donors was larger than that of the acceptors. The present experiments indicated that preparation of low resistance
ohmic contacts by forming a heavily doped intermediate layer between p-ZnSe and metal is extremely difficult by the DA technique. 相似文献
996.
997.
本文提出采用高分子有机材料配合,生产石膏制品防水防潮剂的生产方法和工艺。该剂还可以应用到氧化镁系列板材,同时提出开发珠光或彩色防水防潮剂,能达到满足的装饰效果,值提开发推广。 相似文献
998.
The estimation of the Direction-Of-Arrival (DOA) and the variance of the angular spread, using an array of sensors in the
case of a Ricean channel is considered, using the Maximum-Likelihood, Least-Squares and Weighted Least Squares criteria. The
Cramér-Rao bound is also obtained for the problem of interest. Simplification of the cost functions to reduce the dimension
of the problem has been carried out and the performance of the methods has been studied based on numerical experiments.
A major part of the work was carried out when K V S Hari was visiting the Department of Signals, Sensors and Systems during
Jul–Sep 1995, on leave from the Indian Institute of Science 相似文献
999.
1000.
The mechanisms governing the solubilizing interactions between zwitterionic/anionic mixed surfactant systems at different
molar fractions of the zwitterionic surfactant (Xzwitter) and neutral or electrically charged unilamellar liposomes were investigated. The mixed systems were formed by N-dodecyl-N,N-dimethylbetaine
and sodium dodecyl sulfate in the presence of piperazine-1,4-bis-(2-ethanesulfonic acid) buffer at pH 7.20. Unilamellar liposomes formed by egg phosphatidylcholine, in some cases together
with stearylamine or phosphatidic acid, were used. Solubilization was detected as a decrease in static light-scattering of
liposomes. Two parameters were regarded as corresponding to the effective surfactant/lipid molar ratios (Re) at which the
surfactant system (i) saturated the liposomes, Resat, and (ii) led to a total solubilization of liposomes, Resol. From these parameters the bilayer/aqueous medium surfactant partition coefficients for the saturation (Ksat) and complete bilayer solubilization (Ksol) were determined. When Xzwitter was 0.40, The Re and K parameters showed a maximum, whereas the critical micellar concentration (CMC) of these systems exhibited
a minimum, regardless of the electrical charge of bilayers. Given that the ability of the surfactant systems to saturate or
solubilize liposomes is inversely related to the Resat and Resol parameters, these capacities appear to be directly correlated with the CMC of the mixed systems. The similarity of both Ksat and Ksol (particularly for Xzwitter=0.2–0.8) suggests that a similar partition equilibrium governs both the saturation and the complete solubilization of bilayers,
the free surfactant concentration (Sa,Sb), remaining almost constant with similar values to the CMC for each mixed system studied. 相似文献