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101.
Comprehensive two-dimensional gas chromatography coupled with time-of-flight mass spectrometry (GC×GC-TOFMS) is com-mercially available in the 1990s, with the characteristics of large peak capacity, high resolution, high sensitivity, etc. However, its application to the petroleum and geological analyses is just emerging in China and overseas. In this research, the analytical method for petroleum aromatic fraction using GC×GC-TOFMS is set up, via the choice of the column system and optimization of setting parameters, such as temperature programming, modulation time, hot pulse time, flow rate of carrier gas, data acquisition rate and data processing. The results indicate that different polar compounds of aromatic fraction distribute as bands on structured GC×GC chromatogram. Within each band, homologous compounds appear as a roof-tile structure based on the number of substituent residues. The aromatic compounds are identified and characterized according to the GC×GC chromatogram and mass spectra. According to the polarity and the number of rings, aromatic compounds are spatially present on one chromatogram, which directly reflects the distribution characteristics of complex compounds of aromatic hydrocarbons. In addition, quantitative analysis is favored as some overlapped peaks on traditional GC-MS chromatogram have been separated completely on GC×GC. Some heterocyclic atom aromatic compounds at trace level can be clearly identified using this method, for polarity differences from other interfered aromatic compounds. The development of this method and chromatogram recognition offer petroleum geologists a practical example for the application performance of GC×GC-TOFMS.  相似文献   
102.
The corrosion inhibitor is one of the most important technologies to enhance the durability of steel-reinforced concrete. A kind of time-saving method was developed to assess the inhibitor efficiency by using a 32 V electric field to accelerate chloride ion migration in concrete. Potentiodynamic polarization scanning test was used to evaluate the corrosion states. The comprehensive efficiency of an inhibitor should be assessed in two aspects: resistance to chloride ion permeability and inhibiting efficiency. The specimens with different mixing amount of sodium nitrite and migration corrosion inhibitors were used to verify the accuracy and reliability of this method. The results show the differences in inhibiting efficiency of the inhibitors clearly, indicating the reliability of this time-saving method.  相似文献   
103.
葡萄糖为碳源的EBPR长期运行效果及聚磷菌的富集培养   总被引:1,自引:0,他引:1  
研究了连续运行364 d以葡萄糖为碳源的强化生物除磷(EBPR)系统,比较了3个不同运行阶段典型周期的运行状况,考察了厌氧段聚磷菌(PAOs)对有机底物的贮存转化,运用FISH技术分析了系统菌群结构变化.结果表明:随着运行时间的增加PAOs富集程度增高,第180天后反应器最高厌氧释磷量达到80 mg/L,出水磷浓度小于1 mg/L,以葡萄糖为碳源的EBPR系统可以长期高效稳定运行;与第1和第2阶段相比,第3阶段典型周期效果最佳,其厌氧释磷量达到79 mg/L,PO34--P去除率达到97.2%;葡萄糖先被发酵细菌分解为挥发性脂肪酸(VFA),PAOs吸收VFA合成聚羟基脂肪酸酯(PHA);荧光原位杂交技术分析发现,PAOs比例不断升高,第340天时比例为45.5%,说明以葡萄糖为碳源的EBPR系统可以富集高浓度的PAOs.  相似文献   
104.
旨在探索一种高效的森林资源二类调查成果图编制技术,满足林业工作者在生产中使用分村林相图的迫切需要.按林相图编制要求,采用ArcObjects组件库二次开发方法,提出县域内村界面自动筛选组合设计算法,确定A2幅面布局合理的组合村方案.在ArcGIS环境下,将人工编制过程中繁琐的重复机械操作程序化,实现分村林相图批量编制的自动化.  相似文献   
105.
The distribution of ghrelin-like immunoreactive cells in amphioxus (Branchiostoma belcheri) was investigated by using immunohistochemical staining with rabbit antiserum against synthetical mammalian ghrelin. The results showed that ghrelin-like immunoreactive cells were distributed widely in the nervous system, Hatschek's pit, wheel organ, digestive tract and gonads (ovary and testis). In nervous system, ghrelin-like immunoreactive neurons and their protrusions were distributed specifically on the dorsal side, ventral side and funnel part of brain vesicle, with a few dispersive immunoreactive nerve cells and their fibers in nerve tube. Ghrelin-like immunoreactivities were also detected in Hatschek's pit epithelial cells and wheel organ cells, with positive substance located along cell membrane. In digestive tract, ghrelin-like immunoreactive cells existed in hepatic diverticulum, anterior and posterior region of midgut, and could be classified into two types, closed- and opened-type endocrine cells. The number of positive cells was most in hepatic diverticulum, secondary in posterior region of midgut and least in anterior region of midgut. In gonads, ghrelin-like immunoreactive substance was detected in oogonia, oocytes and follicle cells in ovary at the small and large growth stages and in early spermatogenic cells and Sertoli cells in testis. The extensive distribution of ghrelin-like cells in amphioxus suggested that these kinds of cells are conservative in evolution and diversified in function. At the same time, we found for the first time that ghrelin-like immunoreactive cells existed in brain vesicle and Hatschek's pit, which provided new morphological evidence for the existence of an activation pathway between brain vesicle and Hatschek's pit for the regulation of growth hormone excretion.  相似文献   
106.
The distribution of ghrelin-like immunoreactive cells in amphioxus (Branchiostoma belcheri) was investigated by using immunohistochemical staining with rabbit antiserum against synthetical mammalian ghrelin. The results showed that ghrelin-like immunoreactive cells were distributed widely in the nervous system, Hatschek’s pit, wheel organ, digestive tract and gonads (ovary and testis). In nervous system, ghrelin-like immunoreactive neurons and their protrusions were distributed speci?cally on the dorsal side, ventral side and funnel part of brain vesicle, with a few dispersive immunoreactive nerve cells and their ?bers in nerve tube. Ghrelin-like immunoreactivities were also detected in Hatschek’s pit epithelial cells and wheel organ cells, with positive substance located along cell membrane. In digestive tract, ghrelin-like immunoreactive cells existed in hepatic diverticulum, anterior and posterior region of midgut, and could be classified into two types, closed- and opened-type endocrine cells. The number of positive cells was most in hepatic diverticulum, secondary in posterior region of midgut and least in anterior region of midgut. In gonads, ghrelin-like immunoreactive substance was detected in oogonia, oocytes and follicle cells in ovary at the small and large growth stages and in early spermatogenic cells and Sertoli cells in testis. The extensive distribution of ghrelin-like cells in amphioxus suggested that these kinds of cells are conservative in evolution and diversified in function. At the same time, we found for the ?rst time that ghrelin-like immunoreactive cells existed in brain vesicle and Hatschek’s pit, which provided new morphological evidence for the existence of an activation pathway between brain vesicle and Hatschek’s pit for the regulation of growth hormone excretion.  相似文献   
107.
周成虎  李娜  瓮嘉民  陈冰洋  张昆 《河南科学》2011,29(10):1227-1230
为了能在汽车的引擎盖等活动部位装设车灯,给出了一种无线反馈稳压的非接触供电车灯电路.无线反馈稳压电路通过无线反馈控制电路的输出电压,达到稳定负载功率的目的,实验证明电路可行.  相似文献   
108.
运用Solid Works对单筒减震器进行三维建模,并导入到ANSYS Workbench软件对减震器进行模态分析,获取了其前6阶固有频率和振型。分析了各阶振动模态的特点,得到变形最大区域、变形量情况及振动响应的表现形态。该结果有利于汽车减震器的动态特性分析和整体设计。  相似文献   
109.
本文采用溶胶-凝胶法制备聚酰亚胺/二氧化硅-氧化铝(PI/SiO2-Al2O3)杂化薄膜。运用红外光谱仪、示差扫描量热仪和紫外-可见分光光度计分别测试了亚胺化过程中各阶段杂化膜的特征基团吸收峰的变化,反应热以及紫外-可见光透过率。使用原子力显微镜分析了无机相在亚胺化各阶段的形貌变化。通过这些分析推测了杂化薄膜的分子结构。  相似文献   
110.
A possible two-dimensional viscous magnetohydrodynamics (MHD) model is applied to investigating the plasma armature in a railgun. The space-time conservation element and solution element (CE/SE) method for solving the coupled Navier-Stokes equations and Maxwell equations was devised. The distributions of physical parameters of the plasma may thus be evaluated. The results show that extremely high pressure can always be observed ahead of the projectile, and the Lorentz force is the main propulsion. The distribution of temperature is in a good agreement with the results predicted by the law of radiation at the boundaries. Due to convection, the circulation patterns of velocity are evident in both the cases considering inviscid and viscous effect. Furthermore, the velocity and acceleration oscillate over time until a new steady state is achieved. This model efficiently captures the salient features of the physical phenomena, and contributes to further studies of MHD problems in plasma armature. Supported by the National Natural Science Foundation of China (Grant No. 10672080)  相似文献   
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