First basic performance evaluation of the XE-2100 haematology analyser

The newly developed XE-2100 haematology analyser can provide complete blood counts, leukocyte differentials, perform reticulocyte analysis, and obtain quantitative data on nucleated red blood cells (NRBCs). In this study, we evaluated the basic performance of this instrument using routinely obtained blood specimens treated with ethylenediaminetetraacetic acid-2k. Reproducibility, carryover, stability during storage at 4 degrees C and room temperature, and accuracy were evaluated. In this evaluation, reproducibility was good and little carryover was found. Accurate measurements were possible for up to 48h of storage. A good correlation between findings with the XE-2100 and SE-9000 haematology analysers was found for complete blood count on 210 samples tested. The leukocyte differential obtained with the XE-2100 correlated well with eye counts and with the results obtained with the SE-9000 automated haematology analyser, with r values over 0.9 for the percentages of neutrophils, lymphocytes and eosinophils. The precision and accuracy of VRBC and reticulocyte counts by the XE-2100 were satisfactory. We used the XE-2100 to obtain differential counts for bone marrow aspirates, and good correlations with manual differentials were obtained for total nucleated cell count, percentage of myeloid cells and percentage of erythroid cells. The performance of the XE-2100 was excellent, and this instrument should be able to provide reliable data to clinical laboratories.     

用于环戊烷发泡的组合聚醚的开发

开发了一种能单独用于环戊烷发泡体系的聚醚多元醇ZS-8118,以ZS-8118、匀泡剂、叔胺催化剂、环戊烷、水等原料配制了硬泡组合聚醚。简单讨论了聚醚多元醇品种、匀泡剂及催化剂对发泡体系的影响。结果表明,该组合聚醚贮存稳定性好,制得的泡沫塑料性能优良,能满足冰箱、冷柜等产品的生产要求。     

Evaluation of the Coulter Counter S-Plus VI

This article reports an evaluation of the Coulter Counter model S-Plus VI automatic analyser for haematology, and data are presented on linearity, carry-over, precision, accuracy and stability of the instrument, when compared with a model S-Plus IV/D.The three-part differential count provided by Coulter S-Plus VI has been compared with manual eye counting. The results show a good agreement with only 2.5% of discrepancies in 2271 routine samples.Advantages of the new instrument include: reduction of running costs, largely due to manpower saving; simple and easy use, and improved operator safety, there being no need for human contact with blood.     

Automated bone marrow analysis using the CD4000 automated haematology analyser

At present, bone marrow analysis is performed microscopically, but is time consuming and labour intensive. No automated methods have been successfully applied to classification of bone marrows cells because automated blood cell analysers have been incapable of identifying erythroblasts. The present study was designed to evaluate automated analysis of bone marrow aspirates with the CELL-DYN 4000 (CD4000) haematology analyser, which enables automated determination of erythroblast counts in both the normal mode (haemolytic time; 11.5s) and the resistant RBC mode (34.0s). The percentages of subpopulations including lymphocytes, neutrophils and erythroblasts were obtained with the CD4000, and as a reference, differential counts by microscopic observation of May-Grünwald-Giesa-stained films of bone marrow aspirates were performed (n=98). Significant correlations (P < 0.01) between the results obtained with the two methods were observed for total nucleated cell count and lymphocytes, neutrophils, erythroblasts and myeloid/erythroid (M/E) ratio. However, there were biases in the average percentages of erythroblasts, lymphocytes and M/E ratio obtained using the normal mode with the CD4000 toward values lower than those obtained with the microscopic method. Using the RBC resistant mode with the CD4000, the average percentages of erythroblasts, lymphocytes and M/E ratio approximated those obtained with the microscopic method. In conclusion, the CD4000 in resistant RBC mode is more useful for analysis of bone marrow aspirates than is the normal mode, because the former better approximates the M/E ratio than the latter.     

Multicentre evaluation of the Monarch (IL) clinical chemistry analyser

A multicentre evaluation of the Monarch centrifugal analyser is reported. Precision, linearity and accuracy were assessed by comparison with routine methods. Calibration stability, photometric and dispensing accuracy, and carry-over related to samples and reagents were also evaluated. The overall performance of the instrument was good, showing an excellent photometric and dispensing accuracy, absence of sample-dependent carry-over, and almost negligible reagent carry-over. Good precision, linearity and correlation with routine methods were found for the parameters tested. The instrument is reliable and is now used as the routine clinical chemistry analyser in two of the three laboratories taking part in the evaluation.     

Determination of the Oxidative Stability of Edible Oils - Interlaboratory Test with the Automated Rancimat(R) Method

The performance of the 617-Rancimat(R), an automated analyser made by Metrohm of Switzerland, for determining the oxidative stability of edible oils (Active Oxygen Method) has been examined in an interlaboratory test. The performance of this version of the Swift stability test, carried out by eleven laboratories in the Netherlands and the United Kingdom, was investigated with regard to the determination of the induction period of the oxidative stability of rapeseed oil and palm oil under standardised conditions. Statistical analysis of the results obtained with the 617-Rancimat(R) instrument showed a satisfactory within-laboratory repeatability (5%). Between laboratories, the dispersion of the results around the mean value was rather large (10%).     

Analytical performance of the selective multianalyser Olympus AU 5200

The analytical performance of a selective, automatic multianalyser- the Olympus A U5200 - was tested and assessed for practicability, following ECCLSguidelines. Twenty-two analytes were tested and compared with the Olympus A U5000 analyser. A Hitachi 747 analyser was also included in this survey in order to obtain correlation data for ISE measurements.The imprecision data, expressed as median CV values, were found to be below 2% in series for 21 parameters, and below 3% for 19 paramaters from day to day. Creatinine measured with the kinetic Jaffe method obtained a median CV value of 4% in series, creatine phosphokinase showed the worst imprecision from day to day with a CV of 9%. Slightly better precision values for the majority ofall tests were found on the Olympus AU5200 than on the AU 5000 analyser.The recovery of the assigned values in 32 commercial control sera was between 95% and 105% for 14 tests. Five of the remaining tests yielded recoveries with deviations between 5% and 10%, deviations above 10% showed albumine, alanine aminotransferase, aspartate aminotransferase and creatine phosphokinase. The accuracy of most test parameters was slightly better on the AU5200 analyser than on the comparison instrument.The range of linearity ofthe tested methods covered the range stated by the manufacturers; and no sample carry-over was detected. Most parameters tested yielded close correlation to those on the comparison instrument. Amylase measurements on both analysers correlate well but are not comparable without data correction due to different test methods. In addition, no drift effects were observed over a period of 9 hours.The ion-selective-electrode unit performed well in terms of throughput, precision and stability over time. The whole system showed good practicability with respect to patient sample and reagent handling, a short training period of technicians, ease of system software, maintenence, a robust barcode reader and a flexible host communication procedure.     

Validation of Platelet Counting Accuracy With the Celltac F Automated Hematology Analyzer

Rapid and accurate analysis of platelet count plays an important role in evaluating hemorrhagic status. Therefore, we evaluated platelet counting performance of a hematology analyzer, Celltac F (MEK-8222, Nihon Kohden Corporation, Tokyo, Japan), that features easy use with low reagent consumption and high throughput while occupying minimal space in the clinical laboratory. All blood samples were anticoagulated with dipotassium ethylenediaminetetraacetic acid (EDTA-2K). The samples were stored at room temperature (18^{^}C–22^{^}C) and tested within 4 hours of phlebotomy. We evaluated the counting ability of the Celltac F hematology analyzer by comparing it with the platelet counts obtained by the flow cytometry method that ISLH and ICSH recommended, and also the manual visual method by Unopette (Becton Dickinson Vacutainer Systems). The ICSH/ISLH reference method is based on the fact that platelets can be stained with monoclonal antibodies to CD41 and/or CD61. The dilution ratio was optimized after the precision, coincidence events, and debris counts were confirmed by the reference method. Good correlation of platelet count between the Celltac F and the ICSH/ISLH reference method (r = 0.99, and the manual visual method (r= 0.93) were obtained. The regressions were y = 0.90 x+9.0 and y=1.11x+8.4, respectively. We conclude that the Celltac F hematology analyzer for platelet counting was well suited to the ICSH/ISLH reference method for rapidness and reliability.     

新型高分子助剂在自动洗碗机清洁剂的应用

研究了一种新型高分子助剂Noverite~(TM) AD810的钙离子螯合能力、玻璃杯浸泡老化实验及在含氯或含酶自动洗碗凝胶及自动洗碗粉中的应用性能。实验结果表明,Noverite~(TM) AD810有着良好的钙离子螯合能力,并且不会引起有花纹玻璃杯颜色变化。在所测试的多种自动洗碗机清洁剂产品中,含Noverite~(TM) AD810配方均显示出良好的抗成膜、抗成斑点及阻止碳酸钙沉积在器皿表面性能。     

Enhancing charge-storage capacity of non-volatile memory devices using template-directed assembly of gold nanoparticles

We demonstrate the controlled fabrication of aggregates of gold nanoparticles as a means of enhancing the charge-storage capacity of metal-insulator-semiconductor (MIS) devices by up to 300% at a low biasing voltage of ±4 V. Aggregates of citrate stabilized gold nanoparticles were obtained by directed electrostatic self-assembly onto an underlying nanopattern of positively charged centers. The underlying nanopatterns consist of amine functionalized gold nanoparticle arrays formed using amphiphilic diblock copolymer reverse micelles as templates. The hierarchical self-organization leads to a twelve-fold increase in the number density of the gold nanoparticles and therefore significantly increases the charge storage centers for the MIS device. The MIS structure showed counterclockwise C-V hysteresis curves indicating a good memory effect. A memory window of 1 V was obtained at a low biasing voltage of ±4 V. Furthermore, C-t measurements conducted after applying a charging bias of 4 V showed that the charge was retained beyond 20,000 s. The proposed strategy can be readily adapted for fabricating next generation solution processible non-volatile memory devices.     

Nanoporous rice husk derived carbon for gas storage and high performance electrochemical energy storage

We report on the gas storage behaviour and electrochemical charge storage properties of high surface area activated nanoporous carbon obtained from rice husk through low temperature chemical activation approach. Rice husk derived porous carbon (RHDPC) exhibits varying porous characteristics upon activation at different temperatures and we observed high gas uptake and efficient energy storage properties for nanoporous carbon materials activated even at a moderate activation temperature of 500 °C. Various experimental techniques including Fourier transform-infrared spectroscopy, Raman spectroscopy, scanning electron microscopy, high resolution transmission electron microscopy and pore size analyser are employed to characterise the samples. Detailed studies on gas adsorption behaviour of CO₂, H₂ and CH₄ on RHDPCs have been performed at different temperatures using a volumetric gas analyser. High adsorption capacities of ~9.4 mmol g^?1 (298 K, 20 bar), 1.8 wt% (77 K, 10 bar) and ~5 mmol g^?1 (298 K, 40 bar) were obtained respectively for CO₂, H₂ and CH₄, superior to many other carbon based physical adsorbents reported so far. In addition, these nanoporous carbon materials exhibit good electrochemical performance as supercapacitor electrodes and a maximum specific capacitance of 112 F g^?1 has been obtained using aqueous 1 M Na₂SO₄ as electrolyte. Our studies thus demonstrate that nanoporous carbon with high porosity and surface area, obtained through an efficient approach, can act as effective materials for gas storage and electrochemical energy storage applications.     

Study of the storage performance of a Li-ion cell at elevated temperature

A series of Li-ion cells with a LiCoO₂ cathode, artificial graphite anode and a LiPF₆-based nonaqueous electrolyte were stored at 55 °C in a series of state of charge (SoC) from 0 to 100%. After storage, all the cells except the one stored in 0% SoC exhibited capacity fade and cycling performance decline, which were aggravated by increasing storage SoC. Furthermore, storage at higher SoC increased the safety risk of the cells. The cells stored at SoC higher than 50% could not pass the 3 C/5 V overcharge test, while such a test was easy to pass for the fresh cells and those stored at 0% SoC. The above results show that the fully discharged state is a favorable storage condition to maintain good storage performance of Li-ion cells. In addition, to clarify the aging mechanisms of the cells, XRD (X-ray diffraction), SEM (scanning electron microscopy) and EIS (electrochemical impedance spectra) measurements were carried out. The results indicate that the performance fading of the stored cells is not due to the bulk structure change of the electrode materials, but instead due to the microstructure variation of the cathode, including the decrease in the crystallite dimension, the change of the micro-stress, and the precipitation of the surface films over the electrodes. According to EIS analysis, the increase of the cathode impedance may be the main contributor to the overall degradation of the Li-ion cells after storage.     

燃烧器头部组件用新型高温耐磨材料的研究

本文介绍了中材装备集团有限公司热工分公司为提高燃烧器使用寿命而研发的一种碳化物强化奥氏体耐热钢T810N,通过添加W、V、Ti、Nb等元素来形成高硬度、高熔点的碳化物,从而提高材质的高温耐磨性能。试验研究表明,T810N在高温抗氧化性能、室温及高温拉伸性能、高温耐磨性能方面较ZG40Cr28Ni16有显著提高,能够满足提高燃烧器头部组件使用寿命的要求。     

Extension de l'etude du systeme H+/H/12H2(Pt) vers les hautes frequences

The correct determination of the different parameters of this fast system implies accurate impedance measurements up to 1 MHz at least; we show how such measurements can be performed using a frequency response analyser, associated with a desktop computer, and convenient shaped micro-electrodes. This determination of the different parameters allows us to corroborate and to complete the results obtained by means of pulse methods, and to demonstrate that, in the case of an anodic pretreatment of the electrode, the hydrogen evolution reaction includes an ion + atom recombination step.     

Evaluation of the Technicon Axon analyser

An evaluation of the Technicon Axon analyser was carried out following the guidelines of the ‘Sociedad Española de Química Clínica’ and the European Committee for Clinical Laboratory Standards.A photometric study revealed acceptable results at both 340 nm and 404 nm. Inaccuracy and imprecision were lower at 404 nm than at 340 nm, although poor dispersion was found at both wavelengths, even at low absorbances. Drift was negligible, the imprecision of the sample pipette delivery system was greater for small sample volumes, the reagent pipette delivery system imprecision was acceptable and the sample diluting system study showed good precision and accuracy.Twelve analytes were studied for evaluation of the analyser under routine working conditions. Satisfactory results were obtained for within-run imprecision, while coefficients of variation for betweenrun imprecision were much greater than expected. Neither specimenrelated nor specimen-independent contamination was found in the carry-over study. For all analytes assayed, when comparing patient sample results with those obtained in a Hitachi 737 analyser, acceptable relative inaccuracy was observed.     

Operator-free flow injection analyser

A flow injection analyser has been constructed to allow an operator-free determination of up to 40 samples. Besides the usual FIA apparatus, the analyser includes a home-made sample introduction device made with three electromechanical three-way valves and an auto-sampler from Technicon which has been adapted to be commanded by an external digital signal. The analyser is controlled by a single board SDK-8085 microcomputer. The necessary interface to couple the analyser components to the microcomputer is also described. The analyser was evaluated for a Cr(VI)-FIA determination showing a very good performance with a relative standard deviation for 15 signals from the injection of 100 μl of a 1.0 mg.ml^-1 standard Cr(VI) solution being equal to 0.5%.     

Influence of pore size distribution on methane storage at relatively low pressure: preparation of activated carbon with optimum pore size

Activated carbons prepared by KOH activation of an anthracite were studied for methane storage applications. The effect of the different variables of the activation process (KOH/anthracite ratio, pyrolysis temperature and time) on methane storage and methane delivery was analyzed. Methane delivery was obtained in two different ways: calculated from the isotherm and measuring the volume of methane delivered from a carbon-filled vessel (5 cm³). Both methods give similar values. In addition to the well-known effect of the micropore volume and packing density, special attention was paid to the effect that the micropore size distribution has in methane storage performance. It was shown that this parameter is also a key parameter in the application of activated carbons for methane storage applications. Activated carbons prepared from a cheap raw material and using a single stage activation process have reached very high values of methane storage (155 V/V) and delivery (145 V/V).     

An international round robin test on isothermal (conduction) calorimetry for measurement of three-day heat of hydration of cement

The results of a round robin test on isothermal (heat conduction) calorimetry are presented. A total of 18 participants using three types of instruments conducted 3-day measurements of the hydration of one rapidly hardening Portland cement and one slag-containing cement. The results confirm that isothermal calorimetry is a suitable method for the determination of heat of hydration. As a part of the study, two laboratories also conducted measurements with the standardized heat of solution method. For the Portland cement, these results were in good agreement with the isothermal measurements, but for the slag-containing cement the results differed, both between the two laboratories and between their results and the result of isothermal calorimetry. However, this method performance study clearly shows that the heat of hydration determination of cement by heat conduction calorimetry is more precise than the traditional heat of solution method described in EN 196-8, if state-of-the-art calorimeters are used.     

A novel approach to non-segmented flow analysis. Part 2. A prototype high-performance analyser

A high-performance continuous flow analyser is described, based on gas pressure driven carrier and reagents controlled by computer switched solenoid valves. The principal characteristics of the analyser are discussed and examples of its performance are provided in the form of results obtained using a standard procedure for the determination of Cr(VI). The system was also tested in use with real samples using an ammonium ion analysis on potable and effluent water samples, and the results compared with those obtained using a segmented continuous flow method operated at the Laboratory of the Government Chemist.     

A particulate vortex bed cell for electrowinning: operational modes and current efficiency

The process of electrowinning of copper ions from dilute solutions has been used as a model system to assess the performance of a vortex bed cell with a three-dimensional cathode of conducting particles. Experiments were carried out under three conditions: with constant cell voltage, with constant cell current throughout the process and with exponential decrease of the operating current with time in order to underfollow the limiting current. Results from a batch recirculating system indicate that exponential decrease of operating current with time effects an improvement in current efficiency over a wide range of concentration.Nomenclature specific surface area of particles (cm^–1) - C, C _i concentration of Cu²⁺ ions at the momentt, and initial concentration, respectively (M) - d _p particle diameter (cm) - F Faraday number (96 487 A s mol^–1) - i current density (Am^–2) (calculated for the surface area of the particles) - i _av average current density obtained in the constant cell voltage process (Am^–2) - I _L(t),I _L o limiting current at timet, and initial limiting current, respectively (A) - k _L mass transfer coefficient (cm s^–1) - n number of electrons transferred in the process - Q volumetric flow rate (dm³ s^–1) - R universal gas constant (J mol^–1 K^–1) - t time (s) - T temperature (K) - U cell voltage (V) - V volume of electrolyte (cm³) - v _o volume of particles (cm³) - overpotential (V) - _e current efficiency - , _o bed porosity and porosity of the fixed bed, respectively - =V/Q residence time (s) - see Fig. 2