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1.
颗粒粒度分布测试精度的影响因素   总被引:2,自引:0,他引:2  
不同仪器测出的颗粒粒度分布是不相同的,不宜随意进行直接对比,影响颗粒团聚的因素很多,如显度,颗粒形状,粘接性等,所以,对不同的材料有不同的最宜的分散处理,京城 用颗粒图像分析处理系统时,还要注意有些颗粒有一定的吸光性,因为它山也会影响数据的稳定性。  相似文献   

2.
土壤颗粒对秋茄盐度效应的影响   总被引:2,自引:0,他引:2  
研究了不同土壤颗粒和海水盐度条件下秋茄(Kandelia candel)幼苗生长、净光合速率和蒸腾速率的变化。海水盐度能抑制秋茄幼苗叶片的净光合速率和蒸腾速率,但可以通过增加叶片面积以促进秋茄幼苗的生长和干物质生产,其中50%海水处理大于100%海水处理。土壤颗粒对100%海水浓度下秋茄幼苗的生长有显著的影响,颗粒越小,秋茄幼苗的生长越快,干物质生产越多,但在50%海水浓度下,土壤颗粒的影响不明显,在同一海水浓度下,土壤颗粒对海水盐度抑制秋茄幼苗叶片的净光合速率和蒸腾速率的影响作用不大。颗粒越小,土壤吸收的盐离子越多,Na^ 和H^ 的交换量越大,因此降低了秋茄幼苗根系周围的盐分含量, 有效缓解高盐胁迫对秋茄幼苗生长的影响。  相似文献   

3.
用攀钢工业V2O5为原料采用无机溶胶-凝胶法制备V2O5溶胶和凝胶,并用此胶体不同衬底上制备出透明的半导体V2O5薄膜。研究了胶体粘度对涂膜的影响,以及薄膜电阻率与温度、烘干处理和厚度的关系。用扫描电子显微镜(SEM)研究了薄膜的微观形貌,用XRD研究了薄膜的成份及其变化。结果表明:胶体粘度对涂膜有较大影响;温度、湿份、薄膜厚度对薄膜电阻率均有较大影响;V2O5薄膜由针状V2O5颗粒组成,在衬度上呈均匀分布,且结构比较密集,其颗粒径向尺寸为0.5-1.0μm,长度方向为3.0-5.0μm。烘干处理后颗粒轮廓略有模糊、结构稀疏且尺寸有所长大,同时新生成了一些钒化合物。  相似文献   

4.
纳米颗粒悬浮液稳定性分析   总被引:14,自引:0,他引:14  
讨论纳米颗粒悬浮液的稳定性问题,对不同颗粒、不同基液制备的悬浮液稳定性进行了实验研究,在此基础上,探讨颗粒与基液的密度、颗粒的等效直径、基液动力粘度等因素对悬浮液稳定性的影响。结果表明:颗粒等效直径与基液动力粘度对悬浮液的稳定有决定性作用。  相似文献   

5.
在水介质中分散剂对微细颗粒分散作用的影响   总被引:11,自引:0,他引:11  
研究不同颗粒在水介质中的自然分散行为及分散剂对其分散作用的影响,结果表明,分散剂对二氧化硅,重质碳酸钙,滑石和石墨均有不同程度的分散作用,在分散剂浓度较低区域,4种颗粒的分散规律几乎相似;在高浓度区域,对不同颗粒的分散有共各自的特征,分散剂对重质碳酸钙和滑石颗粒的分散作用比对二氧化硅和石墨的分散作用强烈,对同类矿物颗粒来说,亲水性颗粒较疏水性颗粒的分散作用强烈。  相似文献   

6.
自浮颗粒三相体系的搅拌混合技术(Ⅱ)──挡板的影响   总被引:1,自引:1,他引:0  
研究了不同高度、不同数量和不同布置方式的挡板组合对自浮颗粒三相体系的搅拌混合的影响,发现挡板对自浮颗粒的三相混合有很大的影响,其中不对称的3 块全深度挡板对自浮颗粒的下拉是最有效的,此外回归得到了多种挡板条件下功耗和气含率的关联式  相似文献   

7.
为了提高焦化废水的处理效果,减轻对环境的污染,选择好氧颗粒污泥膜生物反应器处理人工模拟焦化废水,探讨了不同颗粒污泥浓度对焦化废水的处理效果及膜污染的情况。结果表明,不同颗粒污泥浓度对焦化废水的处理效果有显著差别。投加颗粒污泥后,反应器对不同颗粒污泥浓度条件下COD、NH3-N、苯酚、TP的去除效果不同。好氧颗粒污泥内部缺氧和厌氧环境下,反应器中的好氧颗粒污泥质量分数为100%时对COD去除率为99.17%、NH3-N去除率为95.00%、苯酚去除率为99.90%、TP去除率为85.22%。同时,比较了不同颗粒污泥浓度下反应器运行中膜通量的变化趋势及膜表面的变化情况。颗粒污泥投加量的不同对膜污染的抑制作用也不同。颗粒污泥使膜污染减轻,膜通量恢复率升高。  相似文献   

8.
通过对Al2 O3/ 耐热钢基复合材料界面结合强度的测试,分析了不同涂层对界面结合力的影响,对不同颗粒涂层的复合材料进行了900 ℃下的高温磨料磨损试验,并分析了界面结合力对复合材料高温抗磨性的影响.结果表明:颗粒的不同涂层对复合材料界面结合强度的影响较大;颗粒经Ni 涂层处理后与基体的界面结合力增强,作为抗磨硬质相表现出良好的高温抗磨性能;颗粒有TiN 涂层的复合材料由于界面结合强度较低,因而高温抗磨性较差.  相似文献   

9.
研究了不同高度,不同数量和不同布置方式的挡板组合对自浮颗粒三相体系的搅拌混合的影响,发现挡板对自浮颗粒的三相混合有很大的影响,其中不对称的3块全深度挡板对自浮颗粒的下拉是最有效的。此外回归得到了多种挡板条件下功能和气含率的关联式。  相似文献   

10.
界面结合强度对Al2O3/钢基复合材料高温抗磨性的影响   总被引:6,自引:0,他引:6  
通过对Al2O3/耐热钢基复合材料界面结合强度的测试,分析了不同涂层对界面结合力的影响,对不同颗粒涂层的复合材料进行了900℃下的高温磨料磨损试验,并分析了界面结合力对复合材料高温抗磨性的影响,结果表明:颗粒的不同涂层对复合材料界面结合强度的影响较大;颗粒经Ni涂层处理的与基体的界面结合力增强,作为抗磨硬质相表现出良好的高温抗磨性能;颗粒有TiN涂层的复合由于界面结合强度较低,因而高温抗磨性较差。  相似文献   

11.
Language markedness is a common phenomenon in languages, and is reflected from hearing, vision and sense, i.e. the variation in the three aspects such as phonology, morphology and semantics. This paper focuses on the interpretation of markedness in language use following the three perspectives, i.e. pragmatic interpretation, psychological interpretation and cognitive interpretation, with an aim to define the function of markedness.  相似文献   

12.
何延凌 《科技信息》2008,(4):258-258
Language is a means of verbal communication. People use language to communicate with each other. In the society, no two speakers are exactly alike in the way of speaking. Some differences are due to age, gender, statue and personality. Above all, gender is one of the obvious reasons. The writer of this paper tries to describe the features of women's language from these perspectives: pronunciation, intonation, diction, subjects, grammar and discourse. From the discussion of the features of women's language, more attention should be paid to language use in social context. What's more, the linguistic phenomena in a speaking community can be understood more thoroughly.  相似文献   

13.
王慧 《科技信息》2008,(10):240-240
Wuthering Heights, Emily Bronte's only novel, was published in December of 1847 under the pseudonym Ellis Bell. The book did not gain immediate success, but it is now thought one of the finest novels in the English language. Catherine is the key character of this masterpiece, because everybody and everything center on her though she had a short life. We can understand this masterpiece better if we know Catherine well.  相似文献   

14.
The Williston Basin is a significant petroleum province, containing oil production zones that include the Middle Cambrian to Lower Ordovician, Upper Ordovician, Middle Devonian, Upper Devonian and Mississippian and within the Jurassic and Cretaceous. The oils of the Williston Basin exhibit a wide range of geochemical characteristics defined as "oil families", although the geochemical signature of the Cambrian Deadwood Formation and Lower Ordovician Winnipeg reservoired oils does not match any "oil family". Despite their close stratigraphic proximity, it is evident that the oils of the Lower Palaeozoic within the Williston Basin are distinct. This suggests the presence of a new "oil family" within the Williston Basin. Diagnostic geochemical signatures occur in the gasoline range chromatograms, within saturate fraction gas chromatograms and biomarker fingerprints. However, some of the established criteria and cross-plots that are currently used to segregate oils into distinct genetic families within the basin do not always meet with success, particularly when applied to the Lower Palaeozoic oils of the Deadwood and Winnipeg Formation.  相似文献   

15.
理论推导与室内实验相结合,建立了低渗透非均质砂岩油藏启动压力梯度确定方法。首先借助油藏流场与电场相似的原理,推导了非均质砂岩油藏启动压力梯度计算公式。其次基于稳定流实验方法,建立了非均质砂岩油藏启动压力梯度测试方法。结果表明:低渗透非均质砂岩油藏的启动压力梯度确定遵循两个等效原则。平面非均质油藏的启动压力梯度等于各级渗透率段的启动压力梯度关于长度的加权平均;纵向非均质油藏的启动压力梯度等于各渗透率层的启动压力梯度关于渗透率与渗流面积乘积的加权平均。研究成果可用于有效指导低渗透非均质砂岩油藏的合理井距确定,促进该类油藏的高效开发。  相似文献   

16.
As an American modern novelist who were famous in the literary world, Hemingway was not a person who always followed the trend but a sharp observer. At the same time, he was a tragedy maestro, he paid great attention on existence, fate and end-result. The dramatis personae's tragedy of his works was an extreme limit by all means tragedy on the meaning of fearless challenge that failed. The beauty of tragedy was not produced on the destruction of life, but now this kind of value was in the impact activity. They performed for the reader about the tragedy on challenging for the limit and the death.  相似文献   

17.
正The periodicity of the elements and the non-reactivity of the inner-shell electrons are two related principles of chemistry,rooted in the atomic shell structure.Within compounds,Group I elements,for example,invariably assume the+1 oxidation state,and their chemical properties differ completely from those of the p-block elements.These general rules govern our understanding of chemical structures and reactions.Using first principles calcula-  相似文献   

18.
We have developed an adiabatic connection to formulate the ground-state exchange-correlation energy in terms of pairing matrix linear fluctuations.This formulation of the exchange-correlation energy opens a new channel for density functional approximations based on the many-body perturbation theory.We illustrate the potential of such approaches with an approximation based on the particle-particle Random Phase Approximation(pp-RPA).This re-  相似文献   

19.
正The electronic and nuclear(structural/vibrational)response of 1D-3D nanoscale systems to electric fields gives rise to a host of optical,mechanical,spectral,etc.properties that are of high theoretical and applied interest.Due to the computational difficulty of treating such large systems it is convenient to model them as infinite and periodic(at least,in first approximation).The fundamental theoretical/computational problem in doing so is that  相似文献   

20.
<正>"The Journal of Shanghai Normal University:Mathematics"is published by Shanghai Normal University as regular issues of The Journal of Shanghai Normal University each year from 2014 in English.The editors-in-chief of the issues are professors Yuhao Cong and Maoan Han.The Journal of Shanghai Normal University was started in 1958 with  相似文献   

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