Field Load Test Based SHM System Safety Standard Determination for Rigid Frame Bridge

The deteriorated continuous rigid frame bridge is strengthened by external prestressing. Static loading tests wereconducted before and after the bridge rehabilitation to verify the effectiveness of the rehabilitation process. Thestiffness of the repaired bridge is improved, and the maximum deflection of the load test is reduced from 37.9 to27.6 mm. A bridge health monitoring system is installed after the bridge is reinforced. To achieve an easy assessmentof the bridge’s safety status by directly using transferred data, a real-time safety warning system is createdbased on a five-level safety standard. The threshold for each safety level will be determined by theoretical calculationsand the outcomes of static loading tests. The highest risk threshold will be set at the ultimate limit statevalue. The remaining levels, namely middle risk, low risk, and very low risk, will be determined usingreduction coefficients of 0.95, 0.9, and 0.8, respectively.

DETERMINATION OF CREEP PROPERTIES OF THERMAL BARRIER COATING(TBC)SYSTEMS FROM THE INDENTATION CREEP TESTING WITH ROUND FLAT INDENTERS

Indentation creep behavior with cylindrical flat indenters on the thermal barrier coating (TBC) was studied by finite element method (FEM). On ike constant applied indentation creep stress, there is a steady creep rate for each case studied for different creep properties of the TBC system. The steady creep depth rate depends on the applied indentation creep stress and size of the indenters as well as the creep properties of the bond coat of the TBC and the substrate. The possibilities to determine the creep properties of a thermal barrier system from indention creep testing were discussed. As an example, with two different size indenters, the creep properties of bond coat of the TBC system can be derived by an inverse FEM method. This study not only provides a numerical method to obtain the creep properties of the TBC system, but also extends the application of indentation creep method with cylindrical flat indenters.

DETERMINATION OF CREEP PARAMETERS FROM INDENTATION CREEP EXPERIMENTS

The possibilities of determining creep parameters for a simple Norton law material are explored from indentation creep testing. Using creep finite element analysis the creep indentation test technique is analyzed in terms of indentation rates at constant loads. Emphasis is placed on the relationships between the steady creep behavior of indentation systems and the creep property of the indented materials. The role of indenter geometry, size effects and macroscopic constraints is explicitly considered on indentation creep experiments. The influence of macroscopic constraints from the material systems becomes important when the size of the indenter is of the same order of magnitude as the size of the testing material. Two methods have been presented to assess the creep property of the indented material from the indentation experimental results on the single-phase-material and two-phase-material systems. The results contribute to a better mechanical understanding and extending the application of indentation creep testing.

Evaluation of a handheld creatinine measurement device for real-time determination of serum creatinine in radiology departments

AIM: To assess the feasibility/accuracy of a commercial handheld device in the context of increased demand for point-of-care serum creatinine (SCr) determination. METHODS: In this institutional review board-approved, prospective study, 401 patients referred for contrastenhanced computed tomography were included at two centres. Capillary (c)SCr was determined using two devices A+B and venous (v)SCr was determined in the centre's laboratory. Method comparison statistics for both centres and for vSCr<>1.2 mg/dL, receiver operating characteristic analysis, negative predictive values (NPV), sensitivity and specificity were calculated pre-/ post-curve offset correction with vSCr. RESULTS: Pearson's coefficients for cSCr vs vSCr were: centre 1-A:0.93/B:0.92; centre 2-A:0.85/B:0.82 (all P < 0.0001). Overall correlation was better for vSCr > 1.2 mg/dL. The area under the receiver operating characteristic curves showed a high accuracy for cSCr, but the device underestimated SCr, which was confirmed by Bland-Altman plot. Addition of the offset correction factor to the original data from centre 1 resulted in an improvement in sensitivity for detecting patients at risk (> 1.2 mg/dL), whilst maintaining acceptable specificity and improving NPV. CONCLUSION: This study showed the feasibility of SCr determination using the evaluated handheld device in a routine clinical setting. The device showed high sensitivity and high NPV, but may significantly underestimate SCr without offset correction to local laboratories.

Determination of Phenolic Substances in Vidal Blanc Grape

[Objectives] The contents of seven components( gallinic acid,epicatechin,catechin,ferulic acid,chlorogenic acid,rutin,and caffeic acid) in Vidal blanc grape were determined. [Methods]The L9( 34) orthogonal design method was used to optimize the extraction process. High performance liquid chromatography( HPLC) was used to determine gallic acid,epicatechin,catechin,ferulic acid,chlorogenic acid,rutin and caffeic acid in Vidal blanc grape. [Results]The contents of gallic acid,epicatechin,catechin,ferulic acid,chlorogenic acid,rutin and caffeic acid in Vidal blanc grape were 155 1 μg/g,20. 55 mg/g,77. 11 mg/g,0. 738 8,0. 910 0,164. 5 and 175. 8 μg/g,respectively. [Conclusions] HPLC method for the determination of the contents of seven components in the Vidal blanc grape can better control the quality of the variety.

Determination of Binding Parameters of Miramistin to Serum Albumin by the Bioluminescent Method

Bioassay based on the luminescent bacteria was used as a new method for the determination of the kinetic constants of ligand binding to the complexion agent. Miramistin as the cationic surface-active antiseptic and serum blood albumin was taken as a model of interacting agent’s. It was concluded that this approach might have a wide range for applications, namely, in all cases where the ligand is an inhibitor of bacterial luminescence and its complex dose not effect the intensity of this process.

Shaped Insulating Refractory Products——Determination of Cold Crushing Strength

1 Scope This standard specifies a method for determination of the cold crushing strength of shaped insulating refractory products.

Dense Shaped Refractory Products——Determination of Bulk Density, Apparent Porosity and True Porosity

1 Scope This standard specifies the definition, prineiple, apparatus and materials, procedure, expression of resuits and test report of determination of bulk density, apparent porosity and true porosity of dense shaped refractory products.

The Chromosomal Effect of Birchen Dust as Determined by the Micronucleus Test

In a wood processing factory, the measured air concentration of birchen dust was 1. 26 ±0. 41 mg/m3, and the micronucleus frequency of peripheral blood lymphocytes in 83 workersexposed to wood dust was 1. 13 ± 2. 83%, which was significantly higher (P < 0.01 ) thanthat of control group (0. 51 ± 1. 41% ). The number of exposed workers with positive mi-cronucleus test was 9. 6 %, which was higher than that of control group (4. 5 % ), but thedifference was not significant (P >0. 05 ). The micronucleus test in mice treated with waterextracts of unsteamed and unbaked birchen dust showed that the micronucleus frequencies inall treated groups were significantly higher than that of contro group (P < 0. 01 ) and therewas also a doseresponse correlation (r = 0. 96, P < 0. 0005 ). The results of steamed andbaked birchen dust extracts were significantly lower than those of the unsteamed and unbakedones at the same doses (P< 0. 001 ). This suggests that when the birchen dust is steamed atthe temperature of 100℃ for 24h or baked at the temperature of 80℃, its inducing effect inmicronucleus test could be lowered

Determination of Creatinine in PETs and Laboratory Calculations of the Peritoneal Dialysis Adequacy

Since our Department for Dialysis performs the Peritoneal Equilibration Test （PET） to monitor peritoneal dialysis adequacy, our Laboratory has been asked to collaborate on calculating clearances and transport characteristics of patients. This collaboration is ongoing since 2003, despite the Baxter-PD Adequest software having appeared. Our aim is to emphasize the importance of the laboratory in the selection of formulas and specifically in solving the problem of determining creatinine concentration in PETs, and to recommend the cooperation between the laboratory and the dialysis department. Since creatinine determination is encumbered by recommendations for correcting elevated creatinine levels because of the influence of glucose in PETs, we compared results of dialysates determined as serum and as urine. Until now we had 86 patients on continuous ambulatory peritoneal dialysis （CAPD）. Method for determining patients＇ creatinine remains Jaffe kinetic uncompesated although the analyzers and the corresponding reagenses were changed in the laboratory. We have achieved the complete cooperation and confidence in the result, and with the PET test performed strictly according to the protocol, increasingly better results for clearences, Kt/V and transport characteristics. All this helps with treatment planning and analyzing patients＇ quality of life.

Chemical Analysis Method for Carbon Bearing Refractory Products——Determination of Magnesium Oxide Content by CyDTA Volumetric Method

This standard specifies the method summary, reagents, apparatus, sampling, procedure, test results calculation and permissible tolerance of the determination of magnesium oxide by CyDTA volumetric method.

重氮试验在盲插鼻肠管时末端位置判断中的应用效果研究

目的探讨重氮试验在盲插鼻肠管后末端位置判断的应用效果。方法采用便利抽样法,选取2021年9月至2022年1月山东省某三级甲等医院重症监护病房(intensive care unit,ICU)进行盲插鼻肠管术的216名患者为研究对象。采用重氮试验、测pH值、观察回抽液性质三种方式预测鼻肠管末端位置,以X线摄片为判定的金标准,确认鼻肠管末端位置。比较重氮试验及其他两种方式预测的准确率、敏感度、特异度、阳性结果预测值(positive predictive value,PPV)、阴性结果预测值(negative predictive value,NPV)、阳性似然比(positive likelihood ratio,PLR)、阴性似然比(negative likelihood ratio,NLR)等指标。结果pH值判断的敏感度为97.7%、NPV为84.0%、NLR为0.045;回抽液性质判断的特异度为82.9%、PPV为95.5%、PLR为4.912;重氮试验方式的准确率为92.6%、Kappa系数为0.755;受试者操作特征曲线下面积最大为0.870,95%CI(0.793,0.947)。结论重氮试验判断盲插鼻肠管末端位置的准确率、一致性较好,具有较高的临床预测价值。

机收膜杂混合物力学特性测定试验

机收后的废旧地膜含有大量秸秆、根茬等杂质,膜秆混合物各组分的物理力学特性差异影响后续机械分离效果,本文统计分析了膜杂混合物组分占比,并对棉秆力学特性和经过一个生产季的废旧地膜进行抗拉特性测定,试验统计结果显示膜杂混合物中砂土占比46.28%,秸秆占比30.20%,根茬占比6.29%,地膜占比17%。棉秆力学特性测定显示不同直径棉秆的力学特性差异显著,抗压强度范围为16.75~24.63MPa,抗弯强度范围为22.68~27.69MPa。地膜抗拉特性测定结果显示地膜抗拉力为1.28N。研究结果为膜杂混合物分离装置的结构设计和工作参数确定提供依据。

民用飞机飞行中推力确定研究

确定飞行中发动机安装推力对飞机性能计算、发动机推力管理、经济性评价等具有重要意义。飞行中推力无法直接测量,需要在动力装置内部适当位置安装传感器测量性能参数,计算得出飞行中推力。研究了民用飞机动力装置飞行中推力确定方法,给出发动机安装净推力公式。介绍了推力计算的流程,利用某大涵道比涡扇发动机性能试飞数据,计算了该动力装置的安装净推力,并与参考值进行了对比分析,可为民用飞机型号设计提供参考。

电位滴定法测定能力验证样品含量的不确定度评定

目的评定电位滴定法测定能力验证样品含量的不确定度,探讨影响测定的不确定度分量。方法采用电位滴定法测定门冬酰胺一水合物及门冬氨酸含量。建立测量模型,分析不确定度来源,计算各分量的相对标准不确定度及2种样品的合成不确定度。结果门冬酰胺一水合物含量为87.53%,合成标准不确定度为0.24%;门冬氨酸含量为99.68%,合成标准不确定度为0.22%。结论建立了电位滴定法测定能力验证样品含量的不确定度评定方法,且验证结果满意,可为能力验证样品含量测定结果的可信度提供支持。

徐黄合剂的制备工艺优化及含量测定

优化徐黄合剂最佳提取工艺并建立制剂含量测定方法。以黄芪甲苷含量为提取工艺及含量测定评价指标,采用L_(9)(3^(4))正交试验法,选取加水量、煎煮时间及煎煮次数为考察因素确定最佳提取工艺,并考察常压浓缩和减压浓缩对黄芪甲苷含量的影响。另外建立黄芪甲苷高效液相色谱测定方法并进行方法学考察。结果显示,最佳提取工艺为加6倍量水,沸后提取1 h,提取2次;两种不同的浓缩方法对制剂含量影响无显著性差异;黄芪甲苷在0.048 16~0.963 20 mg/mL范围内线性关系良好,阴性样品无干扰,精密度、重复性、稳定性测得的RSD<3%;平均加样回收率为101.85%(RSD=2.54%,n=9),表明该含量测定方法灵敏、准确。

检验检测机构能力扩项申请内容概述

资质认定能力扩项是检验检测机构较为多见的业务申请形式之一,规范化的管理平台网上申请已成为常态化的操作方式。本文对检验检测机构能力扩项需求及其原因进行了分析,以河北省环境检测机构为例简要介绍了能力扩项申请的初步填写内容和能力扩项申请材料的附件,较为详细地对申请材料附件模块进行了具体分析,给出了准备能力扩项申请材料时需要注意的事项,对检验检测机构进行资质认定能力扩项申请及相关工作具有参考作用。

塑料脆化温度的测定能力验证设计研究

为了满足实验室对塑料脆化温度检测能力评估和提高的需求,对塑料脆化温度的测定能力验证中的设备和试验类型选择、试样加工方法、试样材料选择和破坏判定四个关键问题进行研究。实现能力验证方案设备方法涵盖面广、测试样品均匀性好、温度范围应用广泛和破坏情况全面且易判定,为更多具备该项目检测能力的实验室找到检测中存在的问题,提高检测能力,也为实验室认证认可管理部门对该领域获证实验室的监管提供依据。

威廉环毛蚓中8种核苷提取工艺优化及含量测定

目的优化威廉环毛蚓中尿嘧啶、次黄嘌呤、黄嘌呤、尿苷、胸腺嘧啶、肌苷、鸟苷、2′-脱氧鸟苷提取工艺,并测定其含量。方法以料液比、超声时间、超声温度为影响因素,次黄嘌呤、总核苷含量为评价指标,正交试验优化提取工艺。HPLC法测定各核苷含量,分析采用Agilent C_(18)色谱柱(4.6 mm×250 mm,5μm);流动相甲醇-水,梯度洗脱;体积流量1 mL/min;柱温30℃;检测波长260 nm。结果最佳条件为料液比1∶250,超声时间30 min,超声温度60℃。8种核苷在各自范围内线性关系良好(R^(2)>0.9990),平均加样回收率99.11%~103.27%,RSD 0.85%~2.89%。结论该方法稳定可靠,可用于威廉环毛蚓中核苷的提取与含量测定。

黄芪复方制剂供试品溶液制备方法优化

目的优化黄芪复方制剂供试品溶液的制备方法。方法以提取溶剂为影响因素,以扶正强筋片样品中黄芪甲苷含量为考察指标,优选供试品溶液制备方法。并以此方法对4种市售黄芪复方制剂(前列通片、复方石韦片、芪明颗粒、复方血栓通胶囊)进行验证。结果优选方法为在药典方法基础上,用氨试液-水-水饱和的正丁醇(10∶30∶50,V/V/V)混合溶剂进行加热回流提取(含量测定结果为1.09 mg/g,RSD为1.93%)。4种复方制剂测得黄芪甲苷含量为药典方法的1.8~2.6倍,RSD介于1.61%~4.73%。结论该方法快捷高效,专属性、重复性良好,降低了系统误差,结果准确,可用于黄芪复方制剂供试品溶液的制备。