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1.
51. IntroductionL. H5.m.nd..l3] solved the 0problem by using the L2-estimates for partial differentialoperators in C'.. J. Kajiwara[4] studied infinite dimensional generalizations of the poten-tial kernel. Concerning the 0-problem in infinite dimensional spaces, P. ffeb.i.lll] investi-gated the a-equation for coc (o, 1)-forms in arbitrary pseudoconvex open subsets of separableHilbert spaces without growth condition. J. F. Colombeau and B. Perr.t[l1 showed that aCoc solution u of 0u = w ca…  相似文献   
2.
A rigorous finite element analysis procedure is developed to study the effect of the inner structures on the acoustic absorption of multi-layer absorbers. To do this, four types of basic inner structure compartments adopted in the multi-layer absorbers are selected for analysis. These compartments are composed of porous materials inlaid with perforated plates of various shapes, say, triangle, semicircle, convex rectangle and plate shapes. As it is different from the conventional finite element analysis for the acoustic system in the literature, the perforated plates are simulated by appropriate equivalent boundary conditions, depending on their thickness, hole radius, hole pitch and porosity and the air contained in the holes. A large number of total degrees of freedom generated from meshing the air in the holes of perforated plates are thus avoided. The results reveal that the inner structures of the multi-layer absorbers will influence the acoustic absorption at some frequency bands significantly. Based on those features, the multi-layer absorber with a novel inner structure is then designed and manufactured. Both the finite element and experimental results show that its acoustic absorption would be distinctly promoted.  相似文献   
3.
聚烯醇可生物分解且无毒性,可做为土壤改良剂。其在土壤中受温度、紫外线影响而老化的问题为本研究的一部份。以加热及UV处理PVA膜与PVA与SiO2混合物。样品以FT-IR光谱了解其劣化情况。PVA膜与土壤之作用力则以原子力显微镜量测其力曲线与观察表面变化。此外PVA与SiO2混合物则以SEM观察其受热与受UV处理的结果。  相似文献   
4.
自由曲面光学虚拟制造与检测系统的探讨   总被引:1,自引:0,他引:1       下载免费PDF全文
自由曲面光学产品设计、制造与检测的工艺流程,通常采取试凑法逐次逼近。由于加工 检测 再加工,循环往复,既费时,成本又高,产生了瓶颈问题。为了解决此弊端,本文运用虚拟制造技术,提出光学虚拟制造的基本构想,即虚拟制造系统结构模型,给出光学系统虚拟原型的构成和光学系统成像质量虚拟检测系统的构成,讨论光学成像质量的仿真检测以及敏度分析方法。研究结果表明:运用虚拟制造与检测技术,可缩短研发周期,降低成本,优化工艺并提高产品质量。  相似文献   
5.
Production logistics involve the co-ordination of ac tivities such as production and materials control (PMC), inventory management, p roduct life cycle management, etc. Those activities demand for an accurate forec asting model. However, the conventional methods of making sell and buy decision based on human forecast or conventional moving average and exponential smoothing methods is no longer be sufficient to meet the future need. Furthermore, the un derlying statistics of the market information change ...  相似文献   
6.
研究以水泥处理固体有机物时,有机物对水泥水化的影响。以膜流模式说明水份在水泥浆体内传输的现象。水膜存在半干之水泥浆体,其厚度小于100nm,膜流由离分压所驱动,而离分压来自分子间作用力。膜拟结果发现,水泥浆体内局部位置可用以进行水化之水量为Q=-Aslv/6vπ。当有机物添加在水泥浆体内时,会影响Hamaker常数,Aslv因此可能使膜流不稳定或完全抑制膜流,因而使水泥浆体内局部缺水,影响水化进行,造成成品强度降低,影响品质。  相似文献   
7.
We study the average property of the isospin effects of reaction mechanism induced by neutron-halo nuclei within the isospin-dependent quantum molecular dynamics model. We find that the extended neutron density distribution for the neutron-halo projectile brings an important isospin effect into the reaction mechanism, which induces the decrease of nuclear stopping R; however, it induces the obvious increases of the neutron-proton ratio of nucleon emissions (n/p)nucl for all of the beam energies in this work, compared to the same mass stable colliding system.  相似文献   
8.
Abstract: Effects of different radiation treatments on the human immunodeficiency virus-1 (HIV) promoter were reassessed for exposures comparable to those encountered in clinical or cosmetic practice, using survival of the host cell as a basis for comparisons. The exposures were performed with two ultraviolet radiation sources commonly used as medical or cosmetic devices (UVASUN 2000 and FS20 lamps), a germicidal (G15T8) lamp and an X-ray machine. The UVC component of the FS20 lamp was filtered out. The emission spectra of the lamps were determined. The characteristics of these sources allowed us to discriminate among effects of UVA1 (340–400 nm), UVB + UVA2 (280–340 nm) and UVC (254 nm) radiations. Effects of irradiation were ascertained using cultures of HeLa cells stably transfected with the HIV promoter linked to a reporter—chloramphenicol acetyl transferase—gene. The exposures used caused at least two logs of cell killing. In this cytotoxicity range, UVA1 or X radiations had no effect on the HIV promoter, whereas UVB + UVA2 or UVC radiations activated the HIV promoter in a fluence-dependent manner. Survivals following exposure to UVB + UVA2 or UVC radiation were (1) at the lowest measurable HIV promoter activation, 30 and 20%, respectively, (2) at one-half maximal activation, 6 and 3%, respectively and (3) at the maximal activation, 0.5 and 0.2%, respectively. The results suggest that, among the radiations studied, UVB is the most important modality from the viewpoint of its potential effects on HIV-infected individuals, since (1) UVA1 or X radiations have no effects on the HIV promoter, (2) human exposure to UVC radiation is infrequent and (3) human UVB exposure is very common.  相似文献   
9.
A method for quantitative measurement of the photochemical decomposition of the anti-inflammatory agent, indoprofen (INP) is descriped. An RPLC-based assay that could determine the extent of degradation of INP in a rapid, sensitive, and accurate manner was developed. The method was validated under photoirradiation. Quantitation was monitored with an Inertsil ODS-3V column using a mobile phase of acetonitril and 1% HOAc solution in deionized H2O. Statistics relevant to the system criteria, peak integrity and resolution among the parent drug and its degradation products were performed. From the intra- and inter-day tests, the coefficients of variation were found to range from 0.59% to 4.25% for the former and from 0.71% to 4.86% for the latter. The good selectivity and specificity of this RPLC-based procedure render it suitable for measurements of INP stability.  相似文献   
10.
Abstract— In dimethylsulfoxide the emission spectrum of luminol chemiluminescence is red-shifted by 300 cm-1 from the photoexcited fluorescence of the product 3-aminophthalate dianion, while in aqueous solvent the two spectra are identical. The spectral properties of the product dianion have been measured in aqueous solvent and in a number of aprotic solvents, both at room temperature and at 77°K. The ground states and the excited states from which emissions are observed are characterized. Two alternatives are presented to explain the aprotic emission spectra.  相似文献   
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