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101.
Studies were undertaken on the isolation and identification of reaction products of ammonium nitrate phosphate (ANP) fertilizers containing 30, 50 and 70 per cent water-soluble phosphorus (WSP) of total phosphorus in representative soils of the vertisol, oxisol, alfisol, entisol, mollisol and aridisol groups of India. ANP fertilizers were applied in solid form to soil, and reaction products formed at and around the site of ANP fertilizer placement were identified after six weeks incubation in moist soils by X-ray diffraction technique. DCPD (dicalcium phosphate dihydrate- CaHPO4 · 2H2O) was the major reaction product of ANP fertilizers containing 30 and 50 per cent WSP in vertisol, entisol, aridisol, mollisol, oxisol and alfisol, and of ANP containing 70 per cent WSP in vertisol, entisol, alfisol, aridisol and mollisol. DCP (dicalcium phosphate-CaHPO4) was detected with ANP of 30 and 50 per cent WSP in the vertisol, alfisol, entisol, mollisol and aridisol groups of soils. In addition to DCPD, FePO4 · 2H2O (metastrengite) and AlPO4 · 2H2 O-monoclinic (metavariscite) were formed in alfisol and oxisol soils with ANP of 30 and 50 per cent WSP. FePO4 · 2H2O and AlPO4 · 2H2O (metavariscite) were identified in alfisol and oxisol soils while AlPO4 · 2H2O-orthorhombic (variscite) was formed in alfisol soils with ANP of 70 per cent WSP. 相似文献
102.
O. G. Glotov 《Combustion, Explosion, and Shock Waves》2006,42(4):436-449
The condensed combustion products of two model propellants consisting of ammonium perchlorate, aluminum, nitramine, and an
energetic binder were studied by a sampling method. One of the propellants contained HMX with a particle size D
10 ≈ 490 μm, and the other RDX with a particle size D
10 ≈ 380 μm. The particle-size distribution and the content of metallic aluminum in particles of condensed combustion products
with a particle size of 1.2 μm to the maximum particle size in the pressure range of 0.1–6.5 MPa were determined with variation
in the particle quenching distance from the burning surface to 100 mm. For agglomerates, dependences of the incompleteness
of aluminum combustion on the residence time in the propellant flame were obtained. The RDX-based propellant is characterized
by more severe agglomeration than the HMX-based propellant — the agglomerate size and mass are larger and the aluminum burnout
proceeds more slowly. The ratio of the mass of the oxide accumulated on the agglomerates to the total mass of the oxide formed
is determined. The agglomerate size is shown to be the main physical factor that governs the accumulation of the oxide on
the burning agglomerate.
__________
Translated from Fizika Goreniya i Vzryva, Vol. 42, No. 4, pp. 78–92, July–August, 2006. 相似文献
103.
Direct Ink-Jet Printing of Vertical Walls 总被引:1,自引:0,他引:1
Xinglong Zhao Julian R. G. Evans Mohan J. Edirisinghe Jin-Hua Song 《Journal of the American Ceramic Society》2002,85(8):2113-2115
Direct jet printing can assemble ceramic powder into a three dimensional shape by firing droplets of ink through a nozzle to build a multiple layered structure. As with stereolithography and selective laser sintering, the surface texture is expected to witness the layered assembly. The ability to create vertical walls by direct ink-jet printing was explored using a test piece based on a maze. The structure and topography are discussed in terms of droplet spreading and drying. 相似文献
104.
Results of experimental investigations of the action of a coastal surface explosion of a 1000ton TNT charge on the environment are presented. Available databases were used, which are generally utilized for predicting ecological consequences of natural and maninduced explosive catastrophes, development of new methods of monitoring and identification of phenomena under consideration, their experimental and mathematical modeling, and testing of the models being developed. 相似文献
105.
Synthesis of liquid oxygenates from light alkanes (C1--C3) is achieved in a multifunctional three-phase catalytic membrane reactor (3PCMR) operating under mild conditions (TR, 80-120 °C; PR, 140 kPa). The features of superacid catalytic membranes mediated by the Men+/H2O2 Fenton system in activating C1-C3 alkanes are presented. The effect of operating conditions ([H2O2], [Men+]) on the catalyst activity is outlined. A general reaction pathway accounting for the activation of the CH bond of the alkane molecule on the superacid sites and the subsequent reaction of the activated alkane with primary reactive intermediates, generated from the Men+/H2O2 system, is proposed. The suitability of the 3PCMR in enabling simultaneous reaction and product separation is discussed. 相似文献
106.
基于回收质量不确定的现实考虑,运用Stackelberg博弈论方法研究政府补贴和碳税双参与的再制造闭环供应链的定价问题,采用数值仿真的方法量化分析补贴额度和碳税率对再制造闭环供应链定价策略、供应链各成员利润、供应链碳排放量的影响,以及回收质量对再制造闭环供应链的影响。研究发现:政府补贴和碳税的双参与改善了由政府征收碳税而引起的市场不活跃现象,促进了闭环供应链的回收再制造,比单纯补贴或碳税更有效地引导了再制造闭环供应链;无论哪种手段参与,提高废旧产品的回收质量都有助于提高废旧产品的回收量、制造商的利润、第三方回收商的利润以及供应链的总利润,也有助于降低供应链的碳排放。 相似文献
107.
中国加入WTO后,中国洗涤用品行业面临着新的机遇与挑战,中国洗涤用品市场将面临更加激烈的竞争。由于环保的呼声越来越高,中国已开始在部分地区禁磷。中国洗涤用品工业将如何发展,其前景如何,专家的看法又如何,就这些问题本刊专访了有关人士。 相似文献
108.
Benjamin F. Myers 《Journal of the American Ceramic Society》1992,75(3):686-693
The hydrolysis of uranium oxycarbide (UCO) was studied by injecting water vapor into a fuel element containing a known number of high-temperature, gas-cooled reactor (HTGR) coated particles with exposed fuel kernels. The experiments were conducted in the High Flux Isotope Reactor (HFIR) at temperatures between 700° and 1000°C, a system pressure of 200 kPa, and partial pressures of water vapor between 21 and 199 Pa. The general sequential response of the exposed fuel kernels to water vapor addition consisted of (1) a rapid release of stored fission gas with a concomitant increase in the steady-state release and (2) a period of constant steady-state release. Upon cessation of the addition of water vapor, a decline in the release to prehydrolysis values generally occurred. The release of stored fission gas was dependent on the square of the partial pressure of water vapor. The ratio of the constant steady-state release to the prehydrolysis value was independent of the partial pressure of water vapor. The time constant for the decline in the release was the same in all of the hydrolysis tests. 相似文献
109.
110.