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81.
This research extends previous work with dynamic models to manage groundwater quality by using the consumptive nitrate use rate instead of the nitrate application rate. The analysis indicates that misspecification results in overestimation of economic benefits, and supra-optimum nitrogen fertilizer application rates and groundwater nitrate stocks at a steady state.  相似文献   
82.
A family of infinite measure preserving odometers is presented which exhibit examples ofp-recurrent but notp+1-recurrent ergodic transformations for everyp>1.  相似文献   
83.
谐振子薛定谔方程的简单解法   总被引:2,自引:0,他引:2  
物质的许多物理与化学性质都可以用线性谐振子模型解释,本文用简单的数学运算求解线性谐振子的薛定谔方程,避免了特殊函数等复杂的数学运算,得出了量子力学教材完全相同的结果。  相似文献   
84.
A series of Gd(1−x)Bx alloys have been prepared by arc melting method. After introducing small quantity of B atom in Gd, the Curie temperature of these alloys increase while the magnetic entropy changes are almost same as that of Gd. The refrigerant capacities of these alloys are also greater than that of Gd. These results suggest that Gd(1−x)Bx alloys may be utilized as refrigerant in household magnetic refrigeration.  相似文献   
85.
In a conventional diffractometer having single monochromator, only one position, parallel position, is used for the diffraction experiment (i.e. detection) because the resolution property of the other one, anti-parallel position, is very poor. However, a bent perfect crystal (BPC) monochromator at monochromatic focusing condition can provide a quite flat and equal resolution property at both parallel and anti-parallel positions and thus one can have a chance to use both sides for the diffraction experiment. From the data of the FWHM and the Δd/d measured on three diffraction geometries (symmetric, asymmetric compression and asymmetric expansion), we can conclude that the simultaneous diffraction measurement in both parallel and anti-parallel positions can be achieved.  相似文献   
86.
87.
Catalytic decomposition of NO over Cu-Os/13X has been carried out in a tubular fixed bed reactor at atmospheric pressure and the results were compared with literature data performed by high-throughput screening (HTS). The activity and durability of Cu-Os/13X prepared by conventional ion-exchange method have been investigated in the presence of H2O and SO2. It was found that Cu-Os/13X prepared by ion-exchange shows a high activity in a wide temperature range in selective catalytic reduction (SCR) of NO with C3H6 compared to Cu/13X, proving the existence of more NO adsorption site on Cu-Os/13X. However, Cu-Os/13X exhibited low activity in the presence of water, and was quite different from the result reported in literature. SO2 resistance is also low and does not recover its original activity when the SO2 was blocked in the feed gas stream. This result suggested that catalytic activity between combinatorial screening and conventional testing should be compared to confirm the validity of high-throughput screening.  相似文献   
88.
We have reported a novel design of surface plasmon resonance (SPR) device, which uses alternating dielectric layers to enhance the SPR signal quality and modulate its resonant position. Admittance loci method of thin film design has been used in the design of such a device. The use of biomolecular thin film, such as DNAs or Porteins, in this design can result in resonant condition of wavelength changes as well. Bio-plasmonics is proposed for the research and development of novel devices, which use biomolecules as a part of the plasmon oscillation system to actively interact with nano/micro structure.  相似文献   
89.
Radiative heat transfer in an axisymmetric enclosure with absorbing, emitting, and scattering medium is studied here by using the different methods such as MDOM, FVM, and MFVM with emphasis on the treatment of angular derivative term, which appears in curvilinear coordinates due to angular redistribution. After final discretization equation for MFVM is introduced by using the step scheme and directional weights, the present approach is validated by applying it to three different benchmarking problems with absorbing, emitting, and scattering medium. All of the results presented here support its accuracy as well as moderate efficiency. Finally, the present approaches are applied to a truncated cone-shaped enclosure as a body-fitted geometry case.  相似文献   
90.
A recently demonstrated [1] in-vacuo template-stripping process is applied to the study of platinum films stripped from ultra-flat silicon-oxide surfaces. Template-stripped (TS) Pt surfaces, prepared with a range of post-deposition annealing times prior to being stripped from the templating surface in an ultra-high vacuum (UHV) environment, are examined by UHV scanning tunneling microscopy (STM). These studies reveal that without post-deposition annealing, TS Pt surfaces are largely made up of poorly-ordered, granular nanostructures undesirable for many applications. The post-deposition annealing treatments explored in the study result in the emergence and continuous growth of large smooth crystallites. Issues with crystallite orientation relative to the TS surface and artefacts arising as a result of the epoxy used in the template-stripping process are presented and discussed in relation to optimizing the template-stripping procedure for specific applications such as self-assembled monolayer (SAM) formation for molecular electronics. PACS 68.37.Ef; 68.47.De; 68.55.Jk; 81.05.Bx; 81.15.Ef  相似文献   
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