牙齿清洁剂处理洞壁玷污涂层的扫描电镜观察

通过扫描电镜观察,对6组经过不同清洁剂及不同浓度清洁剂处理的龋齿的玷污涂层进行分析观察。结果表明,40%磷酸组,10%EDTA组及0.2%EDTA组能够大部分去除玷污涂层;而0.1%EDTA组只能部分去除玷污涂层。

亚氨乙基赖氨酸对庆大霉素所致豚鼠耳蜗损伤的拮抗作用

探讨亚氨乙基赖氨酸对庆大霉素所致豚鼠耳蜗损伤的拮抗作用。将实验豚鼠分为正常对照组、实验对照组和实验组。实验对照组和实验组豚鼠皮下注射庆大霉素,同时实验组豚鼠腹腔注射亚氨乙基赖氨酸,实验对照组豚鼠腹腔注射等量生理盐水。正常对照组豚鼠皮下及腹腔均注射等量的生理盐水。用免疫组织化学的方法检测诱生型一氧化氮合成酶在各组豚鼠耳蜗中的表达。用ABR检测各组豚鼠听阈的改变,同时以扫描电镜观察耳蜗毛细胞的损伤。结果显示,诱生型一氧化氮合成酶在正常对照组耳蜗的表达呈阴性,在实验对照组和实验组耳蜗的表达呈阳性,且在实验对照组的表达强于实验组。实验组ABR阈移明显小于实验对照组,且实验组耳蜗的损伤明显轻于实验对照组。研究表明,诱生型一氧化氮合成酶在庆大霉素损伤耳蜗中呈阳性表达,亚氨乙基赖氨酸对庆大霉素所致豚鼠耳蜗损伤有明显的拮抗作用,提示一氧化氮在庆大霉素所致耳蜗的损伤中起重要作用。

不育症患者精子头部及尾部超微结构的研究

目的研究不育男性精子超微结构的形态特征。方法利用透射电镜对8例不育男性新鲜精液标本中的精子头及尾部超微结构进行观察。结果在电镜下不育男性精子存在多形态超微结构异常,有以下几种类型:(1)顶体异常精子,包括顶体膜受损,顶体发育不良、缺失,顶体内形成包涵体精子。(2)头部异常精子,包括其尖头精子、圆头精子、头部含空泡精子。(3)尾部异常精子:①尾部形态异常精子,包括无尾精子、短尾精子、卷尾精子、体尾胞质残余;②尾部结构异常精子,包括线粒体缺失精子、尾部线粒体多种形态和结构异常。结论不育男性精子存在顶体、头部、尾部线粒体、微管多种形态和结构异常。

Effect of Oleic Acid Tris-(2-hydroxyethyl) isocyanurate Phosphate Ester on Biodegradability and Tribological Performance of Mineral Lubricating Oil

The oil solubility of synthetic oleic acid tris-(2-hydroxyethyl) isocyanurate phosphate ester(abbreviated as OHTP hereinafter) and its influence on the biodegradability and tribological performance of 400 SN mineral oil were investigated on a tester and a four-ball tribotester,respectively,for fast evaluating the biodegradability of lubricants.Furthermore,the morphologies and tribochemical species of the worn surfaces lubricated by OHTP-doped oil were studied by scanning electron microscope(SEM) and X-ray photoelectron spectroscope(XPS).The results indicated that OHTP possessed good oil solubility and could improve obviously the biodegradability,the extreme pressure properties,the anti-wear properties and friction-reducing properties of the 400 SN mineral oil.The analytical results of XPS spectra showed that the composite boundary lubrication films were mainly composed of absorbed films and tribochemical species such as FePO-4,Fe_3(PO_4)_2,Fe_2O_3 and Fe_3O_4,which contributed to improving the tribological performances.

Influence of ash composition on the sintering behavior during pressurized combustion and gasification process

To determine the ash characteristics during fluidized bed combustion and gasification purposes, the investigation of the impacts of chemical composition of Jincheng coal ash on the sintering temperature was conducted. A series of experiments on the sintering behavior at 0.5 MPa was performed using the pressurized pressure-drop technique in the combustion and gasification atmospheres. Meanwhile, the mineral transformations of sintered ash pellets were observed using X-ray diffractometer （XRD） analyzer to better understand the experimental results. In addition, quantitative XRD and field emission scanning electron microscope/energy dispersive X-ray spectrometer （FE-SEM/EDS） analyses of ash samples were used for clarifying the detailed ash melting mechanism. These results show that the addition of Fe203 can obviously reduce the sintering temperatures under gasification atmospheres, and only affect a little the sintering temperature under combustion atmosphere. This may be due to the presence of iron-bearing minerals, which will react with other ash compositions to produce low-melting-point eutectics. The FE-SEM/EDS analyses of ash samples with Fe203 additive show consistent results with the XRD measurements. The CaO and Na20 can reduce the sintering temperatures under both the combustion and gasification atmospheres. This can be also contributed to the formation of low-melting-point eutectics, decreasing the sintering temperature. Moreover, the fluxing minerals, such as magnetite, anhydrite, muscovite, albite and nepheline, contribute mostly to the reduction of the sintering temperature while the feldspar minerals, such as anorthite, gehlenite and sanidine, can react with other minerals to produce low-melting-point eutectics, and thereby reduce the sintering temperatures.