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111.
薄钢板焊缝(5~15mm)手工超声波捡测,越薄难度越大。但只要选用性能好的短前沿、较高频率、大K值的小晶片斜探头,以数字超声检测仪器组合调试好灵敏度,尽可能以直射波手动检测,应用工艺得当,就能取得较理想效果。手动检测是经济、快捷、实用的无损检测方法。  相似文献   
112.
LZF-1DNA指纹探针经同位素γ-32P-ATP标记后,检测了4个家系13个个体血样的DNA指纹.结果表明,父母的遗传物质在子代中的传递符合孟德尔遗传规律,无误地确定了4个家系中的亲子血缘关系.LZF-1DNA指纹探针在亲权鉴定中的父权概率是0.99964,达到了父权认定的目的  相似文献   
113.
A novel N,N-dithenoyl-rhodamine based fluorescent and colorimetric Fe3+probe 1 was designed and synthesized by only one step from Rhodamine B hydrazide and 2-thiophenecarbonyl chloride.The structure of probe 1 was characterized by ~1 H NMR/~(13)C NMR spectroscopy,IR spectroscopy,and HRMS spectrometry.Accompanying with significant changes in visual color and fluorescent spectrum,probe 1 displayed good sensitivity for Fe~(3+)with an abroad pH span.The detection limit(3.76 μmol/L,0.2 mg/L) for Fe~(3+)was lower than WHO recommended value(0.3 mg/L) for drinking water.Using two thiophene carbonyl groups as coordinating functional recognition group,probe 1 showed excellent selectivity towards Fe3+over diverse coexistent metal ions and anions.The sensing mechanism between dithenoyl-substituted probe 1 and Fe~(3+)was further confirmed by ~1 H NMR and IR titration experiments,binding constants study,and Job's plot analysis.Furthermore,probe 1 also exhibited good cell membrane permeability and could be used as an efficient Fe~(3+) probe in living human cells.  相似文献   
114.
阐述了废弃荧光灯回收利用的潜在意义,介绍了国内外废弃荧光灯资源回收与处置方法。采用回收利用法处理废弃荧光灯,其中包括荧光灯的破碎与物理分离,汞的无害化处理,以及稀土三基色荧光粉的回收和分离。根据稀土三基色荧光粉的特点,目前国外主要采用超临界CO2萃取法、湿法冶金法、风力分选法、离心法和浮选法分离回收稀土,对循环利用稀土资源具有一定的意义。  相似文献   
115.
Recent technological advances allow the detection and quantitation of subsets of leucocytes using monoclonal antibodies. We have taken advantage of this to study the ontogeny of fetal blood leucocytes, using very small blood samples obtained at fetoscopy. By 14 weeks gestation T cells represent 35 per cent or more of fetal leucocytes and the distribution of the helper/inducer and suppressor/cytotoxic subsets is similar to that of adults. B lymphocytes before 161/2 weeks are low (4–20 per cent), but rise to a mean of 28 per cent in 17–26 week fetuses. Granulocytic cells, many of which are phenotypically immature, represent 18–34 per cent of total leucocytes. The methodology employed is very reliable and offers the opportunity for the prenatal diagnosis of some immunodeficiency disorders, since using the same reagents we have diagnosed children with severe combined immunodeficiency shortly after birth.  相似文献   
116.
By aid of fluorescent centromere markers in chromosome No. 3 it could be shown that crossing over in a translocation quadrivalent had occurred on two occasions in a father who is carrier of a 3/5 translocation. This case demonstrates that marker chromosomes cannot always be used to trace the parental origin of structurally abnormal chromosomes.  相似文献   
117.
应用电子自旋探针(Electoron spin probe,简ESP)Mn^2+离子的超精细结构(hyperfine structure,简称hfs),揭示了水泥固化土壤中Cd^2+离子的化学反应,研究发现:由于水泥水化产生高的PH值,Cd^2+离子与OH^-离子反应生成Cd(OH)2沉‘当有CO2气体存在时,Cd^2+离子会与CO2和水泥水化的OH^-离子反应生成CdCO3、Cd(OH)2,这些  相似文献   
118.
Fetal male cells from maternal venous blood were detected by a non-radioactive in situ hybridization method using the biotinylated Y-specific DNA probe pY431. The hybridizations were performed on Ficoll-Paque-isolated nucleated blood cells obtained from 11 pregnant women in the seventh to 31st week of gestation. A Y-specific signal was detected in both granulocytes and lymphocyte-like cells in seven of the 11 women studied. These women gave birth to boys. In one of the four remaining cases, a Y-specific signal was detected in the lymphocyte-like cells but not in the granulocytes. This woman gave birth to a girl. The other three women had no cells with a Y-specific signal and all three gave birth to girls. Altogether, 83 500 nucleated cells were analysed. One hundred and three cells showed a Y-specific signal. Of these Y-specific cells, 62 per cent were granulocytes and 38 per cent lymphocyte-like cells. Our results suggest that fetomaternal transfer of granulocytes is common and that it occurs as early as in the seventh week of gestation. None of the ten non-pregnant female control samples showed positive cells with the Y-chromosome-specific probe; approximately 97 per cent of the cells from the five adult male controls showed a Y-specific signal. Our results indicate that in situ hybridization using a Y-specific DNA probe performed on granulocytes in maternal blood can be used for fetal male sex determination.  相似文献   
119.
为了探讨pH值、离子强度及膜材料对膜-污染物间相互作用力的影响特征,利用自制的典型膜污染物羧基官能团胶体探针,结合原子力显微镜定量考察了羧基官能团与PVDF及EVOH超滤膜间的相互作用力随pH值及离子强度的变化特征.结果表明:带有羧基基体的污染物与PVDF及EVOH超滤膜之间的相互作用力皆随着pH值的增大而减小;但是上述作用力随着离子强度的增加呈现特殊的变化趋势:在离子强度为0~10mmol/L时,膜-带有羧基基体的污染物之间相互作用力随着离子强度的增加而增大;在离子强度为10~500mmol/L时,膜-羧基之间相互作用力随着离子强度的增大而减小.在特定的水质条件下,EVOH-羧基间的作用力远小于PVDF-羧基之间的作用力.  相似文献   
120.
绿色荧光蛋白基因pEGFP经CaCl2转化法标记E.coli JM109菌株,获得的标记菌株作为模式细菌接种含50μg/mL氨苄的LB培养基,在摇瓶中与火山岩颗粒共混培养挂膜(37℃,120r/min,16h).用激光共聚焦扫描显微镜摄取获得火山岩填料生物膜250μm×250μm区域不同层面的图片堆,所获图片堆经COMSTAT程序处理可以获得相关的定量化参数,如16h生物膜平均厚度为0.120844μm,生物膜最大厚度为10.5μm,生物膜体积为0.136986μm3/μm2,生物膜表面积21338.1μm2,生物膜比表面积为3.36854μm2/μm3.该方法也可以扩展至其他绿色荧光蛋白基因标记细菌的生物膜结构定量化.  相似文献   
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