Coupling model uncertainty for coupled rainfall/runoff and surface water quality models in river problems

Coupled hydrology and water quality models are an important tool today, used in the understanding and management of surface water and watershed areas. Such problems are generally subject to substantial uncertainty in parameters, process understanding, and data. Component models, drawing on different data, concepts, and structures, are affected differently by each of these uncertain elements. This paper proposes a framework wherein the response of component models to their respective uncertain elements can be quantified and assessed, using a hydrological model and water quality model as two exemplars. The resulting assessments can be used to identify model coupling strategies that permit more appropriate use and calibration of individual models, and a better overall coupled model response. One key finding was that an approximate balance of water quality and hydrological model responses can be obtained using both the QUAL2E and Mike11 water quality models. The balance point, however, does not support a particularly narrow surface response (or stringent calibration criteria) with respect to the water quality calibration data, at least in the case examined here. Additionally, it is clear from the results presented that the structural source of uncertainty is at least as significant as parameter-based uncertainties in areal models. © 2012 John Wiley & Sons, Ltd.

A study of strong photoluminescence of SiOx : H films

We have examined photoluminescence (PL), IR absorption and Raman spectra of a series of hydrogenated amorphous silicon oxide (a-SiOx:H, (0 < x < 2)) films fabricated by plasma enhanced chemical vapor deposition (PECVD). Two strong luminescence bands were observed at room temperature, one is a broad envelope comprising a main peak around 670 nm and a shoulder at 835 nm, and the other, peaked around 850 nm; is found only after being annealed up to 1170 degrees C in N-2 environment. In conjunction with IR and Raman spectra, the origins of the two luminescent bands and their annealing behaviors are discussed on the basis of quantum confinement effects.

Radiation response of partially-depleted MOS transistors fabricated in the fluorinated SIMOX wafers

Ionizing radiation response of partially-depleted MOS transistors fabricated in the, fluorinated SIMOX wafers has been investigated. The experimental data show that the, radiation-induced threshold voltage shift of PMOSFETs and NMOSFETs, as well as the radiation-induced increase of off-state leakage current of NMOSFETs can be restrained by implanting fluorine ions into the buried oxide of SIMOX wafers.

煤粉颗粒在平面射流喷口附近的湍流弥散研究

一、前言 气-固两相流是多相流研究中活跃的领域之一。煤粉燃烧，喷雾燃烧，喷雾冷却，流化床燃烧等等，都与固体颗粒或液滴的湍流弥散有密切的关系。颗粒的湍流弥散是指颗粒在流体湍流场中的迁移行为。Jeffrey和Pearson1965年发现Saffman力对固体颗粒的运

PHOTOINDUCED CHANGES OF HYDROGEN-BONDING IN SEMIINSULATING IRON-DOPED INDIUM-PHOSPHIDE

After illumination with 1-1.3 eV photons during cooling-down, metastable PH modes are observed by IR absorption at 5 K in semi-insulating InP:Fe. They correlate with the photo-injection of holes, but not with a change of the charge state of the K-related centres present at equilibrium. They are explained by a change of the bonding of H, induced by hole trapping, from IR-inactive centres to PH-containing centres, stable only below 80 K. One metastable centre has well-defined geometrical parameters and the other one could be located in a region near from the interface with (Fe,P) precipitates.

调谐激光晶体Cr（3＋）:ZnWO4光致发光特性的研究

研究了调谐激光晶体Cr~(3+):ZnWO_4的光致发光特性。报道了它的吸收光谱、激发光谱、发射光谱及其随温度的变化、零声子跃迁和发射寿命等实验结果,并讨论了激发特性、电子-声子耦合作用、ZnWO4中 Cr~(3+)的发射寿命曲线等相关问题。

玉米秸秆还田对黑土有机碳库特性的影响

土壤有机碳水平是土壤质量的重要指标，因而一直是土壤学研究的热点。农田管理措施与土壤有机碳含量的维持和提高密切相关。作物残体还田可增加土壤有机碳的含量，而耕作能够加速土壤有机质的分解，影响土壤有机质的转化。由于土壤有机碳库容很大，管理实践所引起的土壤有机碳的改变在相对较短的时间内并无明显体现，但是施入作物残体后，土壤中活性有机碳（如微生物碳，水溶性碳，可矿化碳）很快有所变化，因而这些组分能够作为土壤管理和耕作系统对土壤有机质质量影响的早期指示，也被认为是土壤质量的重要指标。本文将定位试验样品进行团聚体分级后测定上述指标，研究了宽窄行的耕作方式结合玉米秸秆的不同还田方式（高茬还田、粉碎还田、覆盖还田）对土壤有机碳特性的影响，并通过室内培养实验，研究玉米秸秆添加对土壤活性有机碳和无机氮转化的影响，从而为土壤有机碳的管理提供理论依据。 研究结果表明，在五年的宽窄行结合秸秆还田的样地中，秸秆还田显著增加了土壤的大团聚体组分比例。秸秆还田显著增加了土壤总有机碳、全氮的含量，且土壤有机碳增加的部分主要集中在大团聚体组分中，其中玉米秸秆粉碎还田后大团聚体组分中的有机碳含量显著高于高茬和覆盖还田方式。玉米秸秆还田增加了水溶性有机碳和可矿化碳的含量，可矿化碳与冷水溶性有机碳（R2=0.752）和热水溶性有机碳（R2=0.851）有很好的相关性，表明活性有机碳的动态与有机质输入密切相关。秸秆还田也增加了土壤和团聚体中氨基糖的含量，表明秸秆还田可引起土壤微生物的活性增强，其中粉碎还田土壤中氨基单糖增加较多（胞壁酸除外），表明该方式下土壤微生物对输入的有机质的利用效率较高。通过室内培养实验表明，添加玉米秸秆可引起土壤中水溶性有机碳含量和微生物量增加，而加入无机氮后，冷水溶性有机碳的含量降低，但热水溶性碳和土壤微生物量变化不大，说明在无机氮的固持过程中活性最强的有机碳首先被消耗。微生物量与冷水溶性有机碳（R2=0.428）和热水溶性有机碳（R2=0.667）有较好的相关性；玉米秸秆还田方式也影响土壤中无机氮的转化，在粉碎还田的土壤中有更多的NH4+-N被固持，这表明秸秆矿化期间能够提供更多的活性有机碳。 秸秆的不同还田方式对土壤有机碳库特性的影响主要是由于秸秆与土壤的接触程度不同，使秸秆在土壤中的矿化分解速率不同，结果对土壤总有机碳和活性有机碳数量及分布产生影响进而影响无机氮的固持与转化。 关键词：秸秆还田；土壤团聚体；活性有机碳；氨基糖；黑土