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71.
The characteristics of ion beams of hydrogen and nitrogen with different filling pressures emitted from the plasma focus device of 2.3 kJ energy are investigated. CR-39 SSNTDs are employed for the registration of tracks of ions. The exposed detectors are etched in 6N NaOH solution at 70°C and then examined with an optical microscope. The ion flux is estimated to be of the order of 105–6 tracks/cm2. The flux with the radial position does not exhibit any regular pattern of variation. 相似文献
72.
73.
本文介绍了一种实用的液态合金离子源结构,我们利用本结构研制成功了Au-Si和Au-Si-Be液态合金离子源,测出了它们的发射特性。 相似文献
74.
Anatoly M. Dolgonosov Ruslan Kh. Khamizov Anna N. Krachak Andrei G. Prudkovsky 《Reactive and Functional Polymers》1995,28(1)
A model for multispecies ion-exchange kinetics based on the Nernst-Planck equation is suggested. It is analyzed in comparison with the “locally-determinate” model described by Hwang and Helfferich [1]. The model makes possible simple computation. The conditions for the occurrence of unusual kinetic curves with a maximum are clarified. The proposed model is developed for different types of kinetic problems and verified by the experimental investigation of a kinetics in ternary systems. 相似文献
75.
离子注入硅的线源非相干光瞬时退火温度计算 总被引:1,自引:0,他引:1
本文利用高温模型,计算了在我们的实验条件下对离子注入硅进行线源非相干光瞬时退火的退火温度,并与实验结果比较,两者符合得较好。 相似文献
76.
文章从科技哲学视角探析了物联网技术三位一体的内涵,在此基础上,总结了物联网技术在发展过程中面临的技术异化困境、通用目的技术困境和中等收入陷阱困境,最后就如何摆脱以上三大技术困境进行了思考,提出应当从主观意识上防止和消解物联网技术异化,从客观上认识物联网技术的连续性与阶段性统一发展,最终实现物联网技术的自由和谐发展的观点。 相似文献
77.
Ly Thi Thanh Le Lukasz Kotula Kadambot H. M. Siddique Timothy D. Colmer 《International journal of molecular sciences》2021,22(4)
Grain legumes are important crops, but they are salt sensitive. This research dissected the responses of four (sub)tropical grain legumes to ionic components (Na+ and/or Cl−) of salt stress. Soybean, mungbean, cowpea, and common bean were subjected to NaCl, Na+ salts (without Cl−), Cl− salts (without Na+), and a “high cation” negative control for 57 days. Growth, leaf gas exchange, and tissue ion concentrations were assessed at different growing stages. For soybean, NaCl and Na+ salts impaired seed dry mass (30% of control), more so than Cl− salts (60% of control). All treatments impaired mungbean growth, with NaCl and Cl− salt treatments affecting seed dry mass the most (2% of control). For cowpea, NaCl had the greatest adverse impact on seed dry mass (20% of control), while Na+ salts and Cl− salts had similar intermediate effects (~45% of control). For common bean, NaCl had the greatest adverse effect on seed dry mass (4% of control), while Na+ salts and Cl− salts impaired seed dry mass to a lesser extent (~45% of control). NaCl and Na+ salts (without Cl−) affected the photosynthesis (Pn) of soybean more than Cl− salts (without Na+) (50% of control), while the reverse was true for mungbean. Na+ salts (without Cl−), Cl− salts (without Na+), and NaCl had similar adverse effects on Pn of cowpea and common bean (~70% of control). In conclusion, salt sensitivity is predominantly determined by Na+ toxicity in soybean, Cl− toxicity in mungbean, and both Na+ and Cl− toxicity in cowpea and common bean. 相似文献
78.
WANG Xi YANG Genqing LIU Xianghuai ZHENG Zhihong HUANG Wei ZHOU Zuyao ZOU Shichang Ion Beam Laboratory Shanghai Institute of Metallurgy Academia Sinica shanghai China 《金属学报(英文版)》1992,5(11):370-374
A new method for preparation of hard TiN films has been developed by using electronbeam evaporation-deposition of Ti and bombardment with 40 keV Xe~+ ion beam ina N_2 gas environment.The synthesized TiN films were superior to PVD and CVDones in respects of improved adhesion to substrate and low preparing temperature.Theyexhibited good wear resistance and high hardness up to 2200 kg/mm~2.Some industrialapplications have been reported. 相似文献
79.
Amparo Glvez Alfonso Albacete Cristina Martínez-Andújar Francisco M. del Amor Josefa Lpez-Marín 《International journal of molecular sciences》2021,22(7)
Salinity provokes an imbalance of vegetative to generative growth, thus impairing crop productivity. Unlike breeding strategies, grafting is a direct and quick alternative to improve salinity tolerance in horticultural crops, through rebalancing plant development. Providing that hormones play a key role in plant growth and development and stress responses, we hypothesized that rootstock-mediated reallocation of vegetative growth and yield under salinity was associated with changes in the hormonal balance. To test this hypothesis, the hybrid pepper variety (Capsicum annuum L. “Gacela F1”) was either non-grafted or grafted onto three commercial rootstocks (Creonte, Atlante, and Terrano) and plants were grown in a greenhouse under control (0 mM NaCl) and moderate salinity (35 mM NaCl) conditions. Differential vegetative growth versus fruit yield responses were induced by rootstock and salinity. Atlante strongly increased shoot and root fresh weight with respect to the non-grafted Gacela plants associated with improved photosynthetic rate and K+ homeostasis under salinity. The invigorating effect of Atlante can be explained by an efficient balance between cytokinins (CKs) and abscisic acid (ABA). Creonte improved fruit yield and maintained the reproductive to vegetative ratio under salinity as a consequence of its capacity to induce biomass reallocation and to avoid Na+ accumulation in the shoot. The physiological responses associated with yield stability in Creonte were mediated by the inverse regulation of CKs and the ethylene precursor 1-aminocyclopropane-1-carboxylic acid. Finally, Terrano limited the accumulation of gibberellins in the shoot thus reducing plant height. Despite scion compactness induced by Terrano, both vegetative and reproductive biomass were maintained under salinity through ABA-mediated control of water relations and K+ homeostasis. Our data demonstrate that the contrasting developmental and physiological responses induced by the rootstock genotype in salinized pepper plants were critically mediated by hormones. This will be particularly important for rootstock breeding programs to improve salinity tolerance by focusing on hormonal traits. 相似文献
80.