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1.
2.
以SrCO3、BaCO3、H3BO3、Eu2O3和NH4H2PO4为原料,通过高温固相法,合成了2(Sr,Ba)O-0.16B2O3-0.84P2O5:Eu2 荧光粉。通过XRD图谱、激发和发射光谱、光色参数和相对亮度的测量,研究了Ba2 对荧光粉的晶体结构以及发光性能的影响。结果表明:2(Sr,Ba)O-0.16B2O3-0.84P2O5:Eu2 荧光粉属于四方晶系,晶胞参数随Ba2 摩尔含量增加而增大。Ba2 的引入可以显著提高荧光粉的相对亮度,同时,随着Ba2 摩尔含量的增加,荧光粉的发射主峰向短波方向移动,出现蓝移,其色坐标y值逐渐减小,有利于提高白光发光二极管的流明效率和显色指数。  相似文献   
3.
目的基于上转化发光(UPT)免疫层析技术,建立发热伴血小板减少综合征病毒(SFTSV)总抗体的现场快速检测方法。方法将SFTSV重组NP蛋白与上转化发光颗粒(UCP)偶联,制备UCP-NP免疫层析试纸条,评价该试纸条检测SFTSV总抗体的灵敏性、特异性和稳定性,并检测SFTSV血清254份,与酶联免疫法(ELISA)比较。结果该方法可在15min内完成SFTSV总抗体检测,可检测1∶500稀释度的SFTSV阳性血清,与其他出血热病毒无交叉反应,加样14d内稳定性较高。UPT免疫层析法与ELISA法检测临床血清样品一致性极高(Kappa=0.967),约登指数为0.973。结论建立了基于UPT免疫层析技术的SFTSV总抗体快速检测方法,该方法灵敏、特异,且操作简便、快速,结果稳定,适合在基层门诊和体检现场推广。  相似文献   
4.
目的:研制针对4种常见食源性致病菌:甲型副伤寒沙门菌( Salmonella paratyphi A)、乙型副伤寒沙门菌(Salmonella paratyphi B)、大肠埃希菌O157∶H7(Escherichia coli O157∶H7)、副溶血弧菌(Vibrio parahaemolyticus)的基于上转发光免疫层析技术( UPT-LF)的快速定量检测试纸,并对其检测性能进行评价。方法以上转发光纳米颗粒( UCP-NPs)作为示踪物,基于双抗体夹心检测模型,研制针对上述4种靶标菌的UPT-LF试纸;以4种靶标菌的系列浓度标准菌悬液作为标准样品,评价试纸的敏感性、特异性、线性和精密性,并进行模拟染菌食品的检测,评价模拟样品阳性检出率。结果针对4种靶标菌的UPT-LF试纸均具有良好的线性,相关系数r为0.985~0.996;检测敏感性达105~106 CFU/ml,与其他近缘菌株无交叉反应;对乳制品、饮料、小食品、水产、肉类等细菌污染的食品检出率较高。结论该研究建立的对4种常见食源性致病菌进行快速检测的UPT-LF,简便快速,具有良好的敏感性、特异性和线性定量能力,操作性能可满足食品安全检测的要求。  相似文献   
5.
A combustion synthesis method has been developed for synthesis of Eu2+ doped CaAlSiN3 phosphor and its photoluminescence properties were investigated. Ca, Al, Si, and Eu2O3 powders were used as the Ca, Al, Si and Eu sources. The addition of NaN3, NH4Cl and Si3N4 powders was found to increase significantly the product yield. These powders were mixed and pressed into a compact, which was then wrapped up with an igniting agent (i.e., Mg+Fe3O4). The compact was ignited by electrical heating under a N2 pressure of ≤1.0 MPa. Effects of these experimental parameters on the product yield were investigated and a reaction mechanism was proposed. The synthesized CaAlSiN3:Eu2+ phosphor absorbs light in the region of 200–600 nm and shows a broad band emission in the region of 500–800 nm due to the 4f65d1 → 4f7 transition of Eu2+. The sample doped with Eu2+ at the optimized molar ratio of 0.04 is efficiently excited by the blue light (460 nm) and generates emission peaking at ~650 nm with peak emission intensity ~106% of a commercially available phosphor, YAG:Ce3+(P46-Y3).The internal quantum efficiency of the synthesized phosphor was measured to be 71%, compared to 69% of the YAG:Ce3+ (P46-Y3).  相似文献   
6.
Y2O3:Eu is a promising red-emitting phosphor owing to its high luminance efficiency, chemical stability, and non-toxicity. Although Y2O3:Eu thin films can be prepared by various deposition methods, most of them require high processing temperatures in order to obtain a crystalline structure. In this work, we report on the fabrication of red Y2O3:Eu thin film phosphors and multilayer structure Y2O3:Eu-based electroluminescent devices by atomic layer deposition at 300 °C. The structural and optical properties of the phosphor films were investigated using X-ray diffraction and photoluminescence measurements, respectively, whereas the performance of the fabricated device was evaluated using electroluminescence measurements. X-ray diffraction measurements show a polycrystalline structure of the films whereas photoluminescence shows emission above 570 nm. Red electroluminescent devices with a luminance up to 40 cd/m2 at a driving frequency of 1 kHz and an efficiency of 0.28 Lm/W were achieved.  相似文献   
7.
目的 探讨储存磷光质屏放射自显影结合聚丙烯酰胺凝胶电泳测定兔血中12 5I 重组人尿激酶原 (12 5I rhpro UK)浓度的方法。方法 将含12 5I rhpro UK样品的聚丙烯酰胺凝胶贴于储存磷光质屏上曝光 ,根据储存磷光质屏上检出的吸收度值计算12 5I rhpro UK浓度。结果与结论 该方法特异性、线性及线性范围、灵敏度、重现性、回收率均可达到蛋白多肽药物药代动力学研究的要求。并测定了 0 .8mg·kg-1静脉给药时 (12 5I rhpro UK/rhpro UK =1∶9混合 ) ,兔血浆12 5I rhpro UK浓度 -时间曲线  相似文献   
8.
目的评价阿托品不同的给药方法对抢救重度有机磷中毒的疗效和安全性。方法阿托品给药方法A组每次20 mg,静脉推注,每间隔10 min重复给药1次;B组配制1mg/ml的阿托品溶液,持续静脉滴注,速度120ml/h。出现阿托品化后,改为原剂量的2/3并维持阿托品化48h。结果阿托品化时间A组为10.0±2.7h,B组为6.8±1.9h;心率A组平均为110±12.4次/min;B组平均为103±20.6次/min;阿托品中毒出现率A组为8.8%,B组为2.9%;中毒反跳A组为11.7%,B组为2.9%;死亡比例A组为8.8%,B组为2.9%。两组比较(除心率外)差异均有统计学意义(P均〈0.05)。结论重度有机磷中毒患者在使用阿托品治疗时,采用持续静脉滴注的方法危险性小、抢救效果好。  相似文献   
9.
电离辐射剂量监测用热释光探测器   总被引:5,自引:0,他引:5  
用固体能带(晶格能级)理论阐述了热释光探测用于剂理测量的机制;介绍了热释光探测器常用的5种磷光体,即LiF,CaSO4,CaF2,Li2B4O7和BeO的剂量学特性及其优缺点和使用中应注意的问题;给出了热压挤片法、热压切片法、冷压烧结法、毛细管封装法和树脂粘合法等热释光探测器的制备工艺,以及它们的适应范围。  相似文献   
10.

Objective

The aim of this study was to determine (1) the effect of various scan delays on pixel intensity measurements and (2) the diagnostic accuracy of occlusal caries detection.

Methods

72 non-cavitated extracted human permanent molar teeth with sound and carious occlusal surfaces were radiographed using the DIGORA® storage phosphor plates (SPPs) (Soredex Corporation, Helsinki, Finland). Plates were scanned immediately and 10 min, 30 min, 60 min and 120 min after exposure. Three different plates were used for each scan delay. An aluminium (Al) wedge was used to evaluate the change in mean grey values (MGVs) for scan delays. Diagnostic accuracy for occlusal caries detection was performed by scoring all the digital images. The true presence of caries was determined by stereomicroscopy. Comparison of MGVs of the Al wedge for immediate and delayed scans was made using repeated measures analysis of variance (ANOVA) and Tukey–Kramer tests. The accuracy was expressed as the area under the receiver operating characteristics curves (Az). Azs were compared using two-way ANOVA and t-tests. Kappa was used to measure inter and intraobserver agreement.

Results

The mean Azs of immediately scanned plates were higher than the Azs of plates scanned with four different delays (p < 0.05). The Az of immediately scanned images was significantly higher than the Azs of images with 60 min and 120 min scan delays (p < 0.05) but not for 10 min and 30 min delays (p > 0.05). MGVs of immediately scanned plates were significantly higher than the plates scanned with four different delays (p < 0.05). Agreement decreased with increasing scan delays.

Conclusion

Scanning of DIGORA SPPs should not be delayed beyond 30 min for accurate occlusal caries diagnosis.  相似文献   
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