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1.
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   
2.
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   
3.
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   
4.
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   
5.
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   
6.
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   
7.
化学镀法合成纳米Ag包覆Al_2O_3复合粉   总被引:10,自引:0,他引:10  
以平均直径约为200nm的Al2O3粉为原料,以氨基溶液为镀液,硝酸银为初始材料,在反应过程中,控制最佳的还原剂浓度、反应时间等参量,使Al2O3表面获得均匀的金属Ag涂层·以HRTEM,XRD,EDS等手段研究了化学镀银所获得的Ag Al2O3复合粉的结构·结果表明,所有的Ag Al2O3复合粉具有壳 核结构,壳层由纳米非晶银和纳米银晶体颗粒构成,尺度分别是5nm和10nm·  相似文献   
8.
Three kinds of constrained traveling salesman problems (TSP) arising from application problems, namely the open route TSP, the end-fixed TSP, and the path-constrained TSP, are proposed. The corresponding approaches based on modified genetic algorithms (GA) for solving these constrained TSPs are presented. Numerical experiments demonstrate that the algorithm for the open route TSP shows its advantages when the open route is required, the algorithm for the end-fixed TSP can deal with route optimization with constraint of fixed ends effectively, and the algorithm for the path-constraint could benefit the traffic problems where some cities cannot be visited from each other.  相似文献   
9.
The explosive growth of the Internet and database applications has driven database to be more scalable and available,and able to support on-line scaling without interrupting service. To support more client’s queries without downtime and degrading the response time,more nodes have to be scaled up while the database is running. This paper presents the overview of scalable and available database that satisfies the above characteristics. And we propose a novel on-line scaling method. Our method improves the existing on-line scaling method for fast response time and higher throughputs. Our proposed method reduces unnecessary network use,i.e.,we decrease the number of data copy by reusing te backup data. Also,our on-line scaling operation can be processed parallel by selecting adequate nodes as new node. Our performance study shows that our method results in significant reduction in data copy time.  相似文献   
10.
气化是实现化学利用碳资源(尤其是煤)生产化学品和燃料的关键工艺.目前,全球拥有超过272套气化装置,主要应用于煤化工,尤其在中国.由于在一个化工厂通过技术集成达到工业规模的集中生产可实现减少二氧化碳排放并促进碳密集型行业的循环经济,如废物管理、化学和交通行业,因此,近年来全球对垃圾气化的兴趣日益浓厚,尤其是那些在煤气化...  相似文献   
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