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991.
针对夏热冬冷地区间歇式用能特点,采用ANSYS软件对外墙内外保温墙体进行热分析。通过间断式施加温度荷载模拟空调运行,分析两种保温形式的墙体内温度变化情况。研究结果表明,受墙体内侧温度荷载的影响,内保温墙体内表面温度变化明显,且热量集中分布在内侧保温层部分,不易散失;外保温墙体受内侧温度荷载的影响较小,热量在墙体内分布均匀。在相同时间内,内保温需要施加荷载的时间明显比外保温的少。  相似文献   
992.
腐殖活性污泥生化特征及处理效能   总被引:2,自引:0,他引:2  
为探讨腐殖活性污泥的生物化学特征及其作用机理,对腐殖生物填料进行扫描电镜和能谱(SEM-EDAX)测定,表明填料中主要组成元素为C、O、Si,同时含有少量Al、S、Fe. 腐殖活性污泥与普通活性污泥中若干特征菌群的对比分析表明,腐殖活性污泥中的一般细菌总量、硝酸菌、亚硝酸菌、脱氮菌及放线菌含量明显高于普通活性污泥;腐殖活性污泥中有机质的质量分数比普通活性污泥低,但腐殖酸及富里酸和胡敏酸质量分数明显高于普通活性污泥;腐殖活性污泥法运行的SBR反应器对CODCr、TP和TN的去除效果优于普通SBR反应器,分别高出4%、14%和10%.  相似文献   
993.
In order to quantitatively describe the local corrosion process of steel bars in cracked concrete area, a new two-staged utility model is established, and the effect of transverse cracks on the reinforcement corrosion is analyzed from the angle of long-term service performance evaluation for reinforced concrete structure. Moreover, based on the principle of spectral analysis for environmental action of concrete, an equivalent relationship is established between the corrosion rate in the natural environment and that under the standard temperature and relative humidity condition according to the principle of equivalent annual corrosion depth. Comparison between the inspection results from some references and the calculated values by the twostaged utility model validates the feasibility of the proposed model. The model was applied to Chinese Railway Track System(CRTS)Ⅱ ballastless track slab with transverse dummy joints, from which satisfactory results of corrosion degree of steel bars were obtained.  相似文献   
994.
A novel fluorescent probe 9-(4-(1,2-diamine)benzene-N1-phenyl)acridine(DABPA) was synthesized for the detection of nitric oxide(NO) and characterized by IR, 1H-NMR and EI-MS spectroscopy. Based on a photoelectron transfer mechanism, the fl uorescence intensities of DABPA were investigated with the different concentrations of NO. Under the optimal experimental conditions, the fl uorescence intensity of DABPA had a good linear relationship(R2=0.9977) with NO concentration in the range from 1×10-7 to 1.5×10-6 mol/L with a detection limit of 1×10-8 mol/L. The cytotoxicity induced by DABPA was evaluated by the MTT(3-(4,5-dimethylthiazol-2-yl)-2,5diphenyl tetrazolium bromide) assay for biological application. Furthermore, the probe DABPA had also been successfully applied to real-time image NO produced in PC12 cells in the presence of L-arginine.  相似文献   
995.
In order to accelerate the chronic wounds healing, we investigated the healing effects of bioactive glass and Yuunan baiyao ointments in streptozotocin-induced diabetic rats. The ointments were prepared by mixing 45S5 bioactive glass powder (16% weight) with Vaseline and different weight percentages of Yurman baiyao. Full-thickness defect wounds were created on the back of 130 SD rats and were randomly divided into 8 groups. The wound healing rates were calculated at 4, 7, 10, 14 and 21 days after surgery. The samples were harvested for further observations. Considering the wound closure rate, group 6 (with 5% Yuunan baiyao) has better wound healing performance than other diabetic groups. The lower inflammatory response was observed by gross observation and confirmed by the results of H&E staining and TEM observation. Besides, the proliferation of fibroblasts, the formation of granulation tissue, as well as the vascularization, were improved in group 6 compared to other diabetic groups. All results suggest that bioactive glass and Yunnan baiyao ointments can accelerate the recovery of diabetes-impaired skin wounds, and comparing to other diabetic groups, group 6 (with 5% Yunnan baiyao) has better healing effect.  相似文献   
996.
合成了系列钆钐双核稀土有机配合物GdxSm1-x(TTA)3phen(x=0~0.9).红外光谱(IR)、X射线衍射(XRD)、热重(TG)结果推测了配合物可能的分子结构;紫外可见光谱(UV/vis)结果表明,该系列稀土有机配合物能有效的吸收紫外光,吸收峰主要来自于有机配体TTA和phen(270nm和351nm处);荧光光谱(FS)结果表明,Gd3+对于Sm3+具有荧光增效,当Gd3+的摩尔分数为0.6时,Gd0.6Sm0.4(TTA)3phen类配合物的特征荧光(562nm,596nm和643nm处)强度均达到最大.  相似文献   
997.
A circularly polarized microstrip antenna with the tilted beam of 30° through the asymmetrical structure combing the single-arm archimedean spiral antenna with the helix antenna is constructed in order to make the beam tilted. The bandwidth, tilted beam, and radiation characteristics have been improved through the width optimization and coaxial feed line selection. This antenna can realize the directional radiation of circularly polarized microwaves in a definite frequency band and has a bandwidth of 16.7% (for Voltage Standing Wave Ratio(VSWR)<2, Axis Ratio(AR)<3dB and the tilted beam of 30°) in the condition of the vertical aperture external excitation with a coaxial feed line. Simulated and measured results show that this antenna has a wideband, high gain, and tilted beam with circularly polarized microwaves.  相似文献   
998.
该文提出了一种可以广泛应用于四阶PDE曲面的裁剪方法。利用PDE的参数域内的曲线在曲面上投影,得到所求裁剪曲面的边界曲线,然后通过边界曲线的导矢与曲面在边界曲线处的法向量得到边界曲线处的跨界导矢,最后以求得的裁剪曲面的边界曲线以及裁剪曲面在边界曲线处的跨界导矢为PDE曲面的边界条件,用四阶的PDE曲面方程求得PDE裁剪曲面。  相似文献   
999.
In order to precisely retrieve the atmospheric CO2 , a retrieval method based on both near infrared (NIR) and thermal infrared (TIR) is established firstly. Then a look-up-table (LUT) based fast line-by-line radiative transfer model (RTM) was integrated into the retrieval procedure to accelerate radiative transfer calculations. The LUT stores gas absorption cross-sections as a function of temperature, pressure and wavenumber. It could greatly reduce calculating time in radiative transfer compared to direct line-by-line method. Then retrieval was simulated using NIR, TIR and both bands. The retrieved CO2 profiles suggest joint approach could reconstruct CO2 profile better than those using NIR or TIR alone. Joint retrieval using both bands simultaneously could provide better constrain to CO2 vertical distribution in the whole troposphere.  相似文献   
1000.
利用失重法对碳的气化反应、CO气体以及碳还原白云鄂博铁精矿进行了实验,使用矿相、XRD分析了还原后样品的相组成与显微结构。研究结果表明:加入催化剂后,碳的气化反应速率和铁精矿还原速率提高,且K2CO3和Na2CO3的催化效果明显优于CaCO3的催化效果。催化剂的加入有助于碳的活性提高,加速了碳的气化反应,从而促进了白云鄂博铁精矿还原反应进行。  相似文献   
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