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91.
本文利用禹城综合试验站土壤-植物-大气连续体系综合观测场冬小麦田实测资料,对“SPAC系统中水热、CO2通量与光合作用的综合模型(Ⅰ)模型建立”一文所建立的模型土壤水分动态、蒸发蒸腾和冠层CO2通量等功能进行了验证,利用波文比观测水汽通量结果、土壤水分剖面监测结果分别与对模拟计算腾发量和土壤水分剖面的验证结果表明,模拟计算的腾发量和土壤水分剖面是比较准确的;将模拟的光合作用过程中的CO2通量与实测值对比表明,模拟值与实测值的变化趋势是一致的,但是数据上存在一定的差异,模拟光合作用过程和强度符合一般规律,总体说明,所建立的系统模型在上述功能的模拟上是可行的。 相似文献
92.
介绍了一种采用改进型的CLS3700数控测井系统对微电阻率扫描仪数据采集与控制接口的设计及实现方法。基于CLS3700数控测井仪和FMS仪采用89C51单片机设计出通信接口,解决了微电阻率方法。基于CLS3700数控测井仪和FMS仪采用89C51单片机设备出通信接口电路,解决了微电阻主扫描仪现现场实时处理中的瓶颈问题。 相似文献
93.
94.
Danqing Yi Changhai Li Zonghe Lai O. M. Akselsen J. H. Ulvensoen 《Metallurgical and Materials Transactions A》1998,29(1):119-129
Ternary alloying of MoSi2 with adding a series of transition elements was investigated by X-ray diffraction (XRD), scanning electron microscopy, transmission
electron microscopy (TEM), and energy dispersive spectroscopy (EDS). Iron, Co, Ni, Cr, V, Ti, and Nb were chosen as alloying
elements according to the AB2 structure map or the atomic size factor. The studied MoSi2 base alloys were prepared by the arc melting process from high-purity metals. The EDS analysis showed that Fe, Co, and Ni
have no solid solubility in as-cast MoSi2, while Cr, V, Ti, and Nb exhibit limited solid solubilities, which were determined to be 1.4±0.7, 1.4±0.4, 0.4±0.1, and 0.8±0.1.
Micro-structural characterization indicated that Mo-Si-MVIII (MVIII=Fe, Co, Ni) and Mo-Si-Cr alloys have a two-phase as-cast microstructure, i.e., MoSi2 matrix and the second-phase FeSi2, CoSi, NiSi2, and CrSi2, respectively. In as-cast Mo-Si-V, Mo-Si-Ti, and Mo-Si-Nb alloys, besides MoSi2 and C40 phases, the third phases were observed, which have been identified to be (Mo, V)5Si3, TiSi2, and (Mo, Nb)5Si3. 相似文献
95.
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97.
Z Ma S Ramanadham K Kempe Z Hu J Ladenson J Turk 《Canadian Metallurgical Quarterly》1996,1308(2):151-163
We prepared polymers having a phospholipid polar group, poly [omega-methacryloyloxyalkyl phosphorylcholine (MAPC)-co-n-butyl methacrylate(BMA)], as new biomedical materials and evaluated their blood compatibility with attention to protein adsorption and platelet adhesion. The total amount of proteins adsorbed on the polymer surface from human plasma was determined, and the distribution of adsorbed proteins on the plasma-contacting surface was analyzed. The amount of proteins adsorbed on every poly (MAPC-co-BMA) was small compared with that observed on polymers without the phospholipid polar group. However, there was no significant difference in the amount of adsorbed proteins on the poly(MAPC-co-BMA) even when the methylene chain length between the phospholipid polar group and the backbone in the MAPC moiety was altered. Platelet adhesion on the polymer surface from a platelet suspension in a buffered solution was evaluated with and without plasma treatment on the surface. When a rabbit platelet suspension was brought into contact with the poly(BMA) surface after treatment with plasma, many platelets adhered and aggregated. However, a reduced amount of platelet adhered on the poly(BMA) was found in the case of direct contact with the platelet suspension. On the other hand, the poly(MAPC-co-BMA)s could inhibit platelet adhesion under both conditions. Based on these results, it can be concluded that the proteins adsorbed on the surface play an important role in determining the platelet adhesion and suppression of the protein adsorption on the surface, which is one of the most significant ways of inhibiting platelet adhesion. 相似文献
98.
Q Hu M Trevisan Y Xu W Dong SA Berger SD Lyman MD Minden 《Canadian Metallurgical Quarterly》1995,95(6):2530-2538
The growth of human leukemic cells in culture and in vivo is dependent upon the presence of hematopoietic growth factors. Most populations of human leukemic acute myeloblastic leukemia (AML) cells express c-Kit on their surface and respond to Kit ligand (KL) in culture. To determine if this interaction was of potential significance in vivo we used a mouse model system. 32D cells, a murine IL-3-dependent myeloid cell line, were rendered KL responsive by transfection of the murine c-Kit. After injection of 32D or 32D-Kit cells into syngeneic hosts, animals bearing 32D-Kit cells, but not 32D cells, became moribund and were killed. These animals had circulating leukemic blast cells, infiltration of bone marrow, spleen, brain, liver, lung, and kidney. Cells recovered from some of the animals continued to be dependent upon IL-3 or KL for growth while in other cases the cells were factor independent. This model illustrates that the constitutive expression of c-Kit enhances the leukemic potential of 32D cells. The model will be useful for studying the progression of leukemia in vivo and testing whether interruption of the interaction of Kit and KL can affect the growth of leukemic cells. 相似文献
99.
Yi Jin Chieko Toeda Takeo Kawaguchi Toshinobu Seki Kazuhiko Juni 《Drug development and industrial pharmacy》1996,22(7):653-658
Permeation of zidovudine (3'-azido-3'-deoxythymidine, AZT) and probenecid from oily bases containing an alcohol through rat skin was examined. Isopropyl myristate (IPM), as an oily vehicle, showed a penetration enhancing effect for AZT and probenecid. Ethanol, n-propanol, and n-butanol were used as additives in IPM and were examined for their own permeation and the enhancing effect on the permeation of AZT and probenecid. The skin permeation of AZT and probenecid from IPM was enhanced by addition of the alcohol in IPM. The degree of the enhancement was decreased with increasing lipophilicity of the alcohol used. me permeation rate of the drug from those systems was shown to be governed by penetration-enhancing effects of the oily base and alcohol, and the penetration of the alcohol itself through the skin. 相似文献
100.