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The risk-informed safety margin is a new safety concept of nuclear power industry in recent ten years. The calculation framework and the quantification technology under the Monte Carlo method of the riskinformed safety margin were studied. The riskinformed safety margin quantification technology of the station blackout (SBO) accident of nuclear power plant was focused on with the Monte Carlo sampling method. The simplified thermal hydraulic model of nuclear power plant was established with reference parameters of SBO accident in the simplified pressurized water reactor (PWR) model in the INL’s (Idaho National Laboratory) RISMC research. And the calculation process of the riskinformed safety margin based on Monte Carlo sampling method was determined. The number of scenarios generated by Monte Carlo sampling was essential to ensure the acceptability of the accuracy of the calculation results, and the accuracy of estimated value of probability safety margin would be higher if we establish more scenarios. The sampling times estimation method and the reliability calculation method of Monte Carlo were referenced, and a quantitative method of riskinformed safety margin with Monte Carlo sampling was proposed. The sampling times estimation method under the given error was given. According to the uncertainty calculation method of the riskinformed safety margin with Monte Carlo method and the estimation process of sampling times in Monte Carlo, the sampling times were determined by relative error and absolute error respectively. The results show that absolute error is equal to 001 with the 4 706 sampling times, and relative error is equal to 5% with the 9 604 sampling times in the riskinformed safety margin in SBO accident. The mean value and standard deviation of the failure probability of nuclear fuel cladding were calculated with these two sampling times. At this stage with the usual calculation of resource allocation, it is suggested that when the average failure probability of nuclear fuel cladding is larger than 01, the sampling times with 5% relative error should be selected. And when the mean value of failure probability of nuclear fuel cladding is equal to or lesser than 01, the sampling times with relative error equal to 10% could be used. The change of the mean value of failure probability of nuclear fuel cladding under the Latin hypercube sampling and random sampling method was studied. The relationship of the mean value with the recovery time of emergency diesel engine under different distributions was researched too. The calculation results indicate that the different sampling methods and different normal distributions have significant effects on mean value and standard deviation of the failure probability of the nuclear fuel cladding.

BACKGROUND From 1986 to 2007, different grades of trace gold certified reference materials (background grade, anomaly grade, medium grade and high grade) and mineral gold certified reference materials (mineralization grade, cutoff grade and concentrate grade) had been developed by IGGE and used for regional geochemical survey, mineral exploration and evaluation, mining and smelting. With the increase of the service life period and the consumption of recent years, most of the gold certified reference materials has been used up or almost used up. New gold standard materials need to be developed urgently. OBJECTIVES To develop a new gold certified reference material and compare it with the original gold certified reference material. METHODS The trace gold certified reference materials in 7 levels and mineral gold certified reference materials in 3 levels were prepared in strict accordance with relevant specifications. The collected candidates were sampled from different types of deposits and different matrices. The collected candidates were prepared through coarse crushing, drying, composite configuration, fine crushing, sieving, blending and other steps. After the particle size inspection, the cumulative content of the sample with a particle size of 0.74μm reached more than 99%, which met the requirements of the specifications. 25 bottle samples of each grade were randomly selected. Homogeneity testing was carried out by ICP-MS, FAAS and GFAAS. RESULTS The relative standard deviation (RSD) was less than 10%, and the F values of the variance test were less than the one-tailed critical value F0.05(24, 25) of 1.98, indicating that the sample uniformity was good. During the one-year investigation period, no significant changes in statistical significance were found in the fixed value components, which proved that the stability of the sample was good. Five highly experienced and skilled laboratories in geology gold samples testing in CHN were invited to evaluate the gold certified reference materials by classically reliable analytical methods. The original data conformed to the normal distribution after statistical inspection and the suspicious values were eliminated. The arithmetic mean was used as the standard value, and the uncertainty was evaluated in detail, in accordance with the latest specifications. The certified value of the copied standard material was accurate and reliable, and the uncertainty was reasonable. It was approved as a national first-level standard material in 2019. Compared with the original batch, the certified values of the two batches were basically the same, and the standard deviation of the fixed value data showed a shrinking trend, which met the requirements for copying standard materials. CONCLUSIONS This series of gold standard materials has a wide content range, and meets the value comparison and analysis monitoring of different content levels. Moreover, it has good applicability, and meets the needs of geological and mineral research, regional geochemical investigation, gold mine exploration and evaluation.

BACKGROUND With the increased attention paid for the construction of ecological civilization, a comprehensive survey of natural resources is imperative, and new requirements for biological reference materials have also been put forward. At present, relevant research work has been widely carried out. The comprehensive investigation of natural resources, agricultural products and food safety evaluation all need to accurately test the element composition of biological samples, and biological reference materials are needed as the basis for the comparison and traceability of biological components. The demand for biological matrix reference materials has increased significantly. As one of the main foods, the food safety of rice has been paid more and more attention. It is of great practical significance to carry out accurate analysis of the chemical components in rice. Therefore, the demand for rice is particularly prominent, but the rice reference materials for composition analysis are still lacking. OBJECTIVES To develop rice certified reference material (GBW10010a) and compare it with the data characteristics of GBW10010. METHODS The rice certified reference material (GBW10010a) was prepared in strict accordance with relevant specifications. The collected candidates were prepared through coarse crushing, drying, fine crushing, sieving, blending and other steps. The particle size distribution was detected by BT-9000ST laser particle size analyzer. 15 bottle samples were randomly selected and homogeneity testing was carried out by ICP-MS and ICP-OES, etc. The data were statistically calculated by one-way ANOVA, indicating good homogeneity of the samples. The long-term stability of the standard material under the specified storage conditions was investigated. The linear model was used to evaluate the stability of the sample. The determination of 60 components was carried out by means of ICP-MS, ICP-OES, AFS, COL, VOL, XRF, IC and other Analytical test methods. RESULTS The rice reference material prepared in this research has diverse fixed value components, accurate and reliable measurement values, and meet the requirements of national first-level reference material. GBW10010a has a total of 54 main trace elements. 39 elements have certified values and uncertainties and 15 elements only have reference values. The content of heavy metal elements such as As, Cd, Co, Cr, Cu, Hg, Mn, Mo, Ni, Zn in GBW10010a decreased significantly, among which Cd, Cu, and Zn decreased by about 39%, 43% and 38.7%, respectively. CONCLUSIONS To a certain extent, the values reflects the improvement of farmland ecological environment. Compared with the original GBW10010, the total number of certified value elements has increased by 6 items, including Ag and Nb (Nb gives reference values). Moreover, the uncertainty of each element is reduced, including biological-related elements Al, Cd, Cu, Fe, K, Mg, Mo, Na, P, Pb, Se, and Zn. The reduction indicates the technological advancement of the geological analysis and the improvement of the certified value level. In addition, the content of heavy metal elements in GBW10010a decreased significantly, reflecting the improvement of farmland ecological environment. The designated elements of the reference materials cover most of the main and trace elements with biological effects, and are suitable for the calibration of analytical instruments, evaluation of analytical methods, and monitoring analytical quality during agricultural ecological environment geochemical surveys and evaluation, biological sample analysis, agricultural product quality and food safety evaluation.

When solving traveling salesman problem (TSP), the ant colony algorithm is easy to fall into local optimum and convergence speed is slow, a double-type ant colony algorithm considering dynamic guidance and neighborhood interaction is proposed. Firstly, the algorithm combines the dynamic guidance strategy to increase the dynamic pheromone belonging to the path of the largest spanning tree in the early iteration, thereby effectively increasing the diversity of the population; adding the dynamic pheromone belonging to the path of the minimum spanning tree in the late iteration to accelerate the convergence speed. Furthermore, the ants are divided into two categories, which are integrated into the neighborhood interaction strategy, and the second type of ants improve the state transition and the local pheromone update formula through the attraction factors, and use the MMAS (max-min ant system) pheromone restriction strategy, which not only improves the convergence, but also prevents the algorithm from early stagnation. The experimental results of solving the TSP test set and compared with other improved ant colony algorithms show that the improved algorithm can effectively accelerate the convergence speed and avoid falling into local optimum, thus obtaining a more accurate solution, especially in the case of large-scale TSP problems, the effect is more significant.

BACKGROUND Floodplain sediment, which is an important sampling media for geochemical mapping, can represent the average distribution of elements in the basins and has universal applicability. At present, there is no floodplain sediment reference material in the world. The development of similar standards in foreign countries focuses on the environment, and there are fewer fixed components. The same standards for soil and river sediments in China are limited by different work needs, and the development aims are different. Most of the standard substances are insufficient. To develop 7 national first-level reference materials for floodplain sediments in the Yangtze River, Gan River, Han River, Huaihe River, Yellow River, Haihe River and Heilongjiang River (GBW07385-GBW07391). CANDIDATES CHARACTERISTICS:Sample GSS-29 is the floodplain sediment of the Yangtze River. It is grayish yellow and contains high contents of silty. GSS-30 is the floodplain sediment of the Gan River, which is sub clay with relatively fine particle size. GSS-31 is the floodplain sediment of the Han River, which is gray-black, fine-grained and contains relatively high contents of organic matter. GSS-32 is the floodplain sediment of the Huaihe River, which is grey-black, fine-grained and clay-like. GSS-33 is the floodplain sediment of the Yellow River, which is black clay with relatively fine grain size and relatively high contents of organic matter. GSS-34 is the floodplain sediment of the Haihe River, which is sub clay with a relatively fine grain size and high content of clay formed in block. GSS-35 is the floodplain sediment of the Heilongjiang River, which is black and loose, with a relatively fine grain size and high content of clay where some are formed in block. METHODS A series of reference materials was tested using X-ray Fluorescence Spectrometry to measure 26 components. The RSD of the main components was less than 1%, the RSD of minor elements was 2% and the RSD of trace components was less than 7%. The F value of the variance test was less than the list threshold F0.05(24,25)=1.96, indicating that all seven materials were homogeneous. No significant statistical changes were found in the 24 elements and compounds tested within 23 months, indicating that the stability of these materials were stable. Thirteen laboratories have participated in this inter-laboratory program, and have adopted various reliable analytical methods based on different principles to set the values. RESULTS A total of 511 characteristic components, including 73 elements and compounds, have been tested. In addition to the CO2 values of GBW07386 and GBW07388 that cannot be assigned, the remaining 494 characteristic components are given the certified value and uncertainty, and 15 characteristic components are given information value. The trace elements in GSS-29 have the mostly high background contents. The trace elements in GSS-30 have medium background values, and the contents of W, Sn and Mo are relatively high. The contents of Cd and Mo in GSS-31 are relatively high. The trace elements in GSS-32 have low background contents, and the contents of Cd, Hg, Mo, N, S and P are lower than the background level. The content of Hg in GSS-33 is very low. The trace elements in GSS-34 have the mostly medium and high background levels, and the contents of F, Cl and Br are relatively high. The organic matter content of GSS-35 is relatively high. CONCLUSIONS The seven reference materials for floodplain sediments have been certified by the General Administration of Quality Supervision, Inspection and Quarantine of the People's Republic of China (AQSIQ) in 2017. This series of floodplain sediment certified reference materials (GBW07385-GBW07391) represents the background values of the elements of each corresponding drainage area. It can be used for monitoring the quality of geochemical sample analysis or the quality of sample analysis in other fields, such as environment and agriculture.

Accurate analysis of chemical compositions is vital for exploration and comprehensive utilization of molybdenum minerals. Reference materials can provide criterion and technical support for the chemical composition analysis. At present, there are insufficient reference materials of molybdenum ore and concentrate in series. Most molybdenum ore and concentrate national materials are depleted in China. In order to meet the demand of molybdenum resources exploration, development and trade, three molybdenum ore and 1 molybdenum concentrate reference materials have been prepared, in which the contents of Mo are 0.066%, 0.15%, 0.54% and 50.08%, respectively. Original samples of these reference materials were collected from Henan province which has the largest reserves of molybdenum resource in China. Samples of molybdenum tailing (Mo: 0.02%), molybdenum ore (Mo: 0.09%) and molybdenum concentrate (Mo: 50.0%) were collected. Three molybdenum reference materials were prepared through a weight combination method with corresponding original samples. The molybdenum concentrate reference material was prepared by directly crushing the original sample of molybdenum concentrate. In order to prevent sulfides in molybdenum concentrate from oxidizing, a ball mill was filled with argon during the grinding procedure of the sample. According to the national standard reference materials criterion, a variety of methods at 13 laboratories were applied to determine the chemical compositions. 26 indices including metallogenetic elements (Mo), elements for comprehensive utilization (W, S, Cu, Pb, Zn, Fe, Bi), trace elements for mineral exploration (Ag, As, Cd, Mn, P, Pb, Sb), and principle components in gangue (SiO2, Al2O3, Fe2O3, CaO, MgO, Na2O, K2O) were determined. These reference materials show good homogeneity, stability, standard value and reasonable uncertainty after corresponding statistical tests. They are a good supplement to improve existing reference materials and have already been certified and approved as national primary Certified Reference Materials (CRMs) by General Administration of Quality Supervision, Inspection and Quarantine of the People′s Republic of China (serial numbers: GBW 07141-GBW 07144), which can be used to give criterion and quality monitoring to analysis in the process of molybdenum minerals exploration, development, beneficiation, metallurgy and trade.

Objective: To investigate the role of airflow parameters of some specific examinations in voice function assessment., Methods: The s/z ratio, pulmonary function and phonatory aerodynamic parameters were measured in subjects with benign vocal fold lesions and with normal voice. The effect of treatment in subjects with benign vocal fold lesions was evaluated with the phonatory aerodynamic parameters., Results: The value of s/z ratio in the disease group was higher than that in the normal group (P<0.05). The value of PEF was significantly different between the disease group and the normal group for male (P<0.05). MFR, MPT, PTF, SGP, PTP, VE were significantly different between the disease group and the normal group (P<0.05). MFR, MPT, PTF, SGP, PTP of the disease group after surgery for both sex were significantly different from before surgery (P<0.05). The disease group was subdivided into two groups through stroboscopic examination before and one month after surgery: the worse group (with some functional laryngeal abnormality, or organic abnormality except benign vocal fold lesion) and the better group. PTF, PTP, SGP, VE were significantly different between the worse group and the normal voice group. There was almost no significant difference for aerodynamic parameters between the better group and the normal voice group (P>0.05). There was no significant difference between the worse group after 8 weeks'voice training and the normal voice group (P>0.05)., Conclusions: s/z ratio, aerodynamic parameters (MFR, MPT, SGP, PTF, PTP, VE) are valuable for the diagnosis and assessment of the voice disorders. Aerodynamic parameters are sensitive to the change of glottal function during the treatment. Voice training can increase the glottal function of patients after laryngeal microsurgery.

A method was established for the simultaneous determination of nine heterocyclic aromatic amines (HAAs) in mutton products by solid phase extraction-high performance liquid chromatography (SPE-HPLC). As a result, the sample was prepared by ultrasound in 2 mol/L NaOH, and dichloromethane was selected as the extraction solvent. The extract was purified and concentrated with an MCX SPE column. The chromatographic separation was achieved on a reverse-phase C18 column by gradient elution using 0.01 mol/L phosphoric acid (adjusted to pH 3.6 by triethylamine) and acetonitrile, detected with a diode array detector (DAD) at 228 nm for 2-amino-9H-pyrido [ 2,3-b] indole (AaC) and 2-amino-3-methyl-9H-pyrido [ 2,3-b] indole (MeAaC); 253 nm for 2-amino-3-methylimidazo[4,5-f]quinoline (IQ), 1-methyl-9H-pyrido[3, 4-b] indole (Harman), 9H-pyrido[3,4-b] indole (Norharman); 263 nm for 2-amino-3,8-dimethylimidazo[4,5-f]quinoxaline (MeIQx), 2-amino-3,4,8-trimethylimidazo [4,5-f] quinoxaline (4, 8-DiMeIQx), 3-amino-1-methyl-5H-pyrido [4,3-b] indole (Trp-p-2); 321 nm for 2-amino-1-methyl-6-phenylimidazo [4,5-b]pyridine (PhIP). The results showed that the nine HAAs can be separated efficiently. The recoveries (n = 6) of the nine HAAs spiked in meat were between 50.27% and 94.77% with the relative standard deviations of 0.08%-4.42%. The limits of detection of this method were 1.6 -41.0 microg/L for the nine HAAs. The method is simple, accurate, rapid and repeatable. It can be used for the simultaneous determination of the nine HAAs in mutton products.

Real world vehicle emission tests were conducted on two heavy-duty diesel trucks on un-loaded and loaded condition by using a portable emission measurement system. By analysis, the results indicate high fuel consumption and emission rates are concentrated on the high speed and acceleration areas of the speed-acceleration emission maps and the areas are much wider on loaded condition. The impact of load on fuel use and emissions will be highest while the vehicle is cruising or accelerating on (30 +/- 2.5) km x h(-1), which are 1.6 - 3.2 times of those on un-loaded condition. Synthetically, the comprehensive fuel consumption and CO, HC, NO(x) emission factors of truck I and truck II on loaded condition are respectively 1.6, 3.5, 1.1, 1.5 times and 1.2, 1.0, 0.9, 1.5 times of those without load. Load has greatest impact on fuel consumption and NO(x) emission and less effect on HC emission. As for the CO emission, it depends on the maintenance of the truck. It can be figured out from the results on two trucks that the impact of same load will be lower on a vehicle with lager type and more powerful engine, which means if one vehicle is loaded on its acceptable range of GVWR, fuel use and emissions caused by heavy loads could be decreased correspondingly.

Objective: To explore the implication of karyotype analysis in diagnosis and prognosis of myelodysplastic syndrome (MDS)., Methods: The chromosomes were prepared with direct method, brief culture of cells and R-banding techniques, and then the karyotypic analysis was performed., Result: Seventy-seven out of 283 patients (27.21%) had karyotypic abnormalities, including the numeral abnormalities of chromosomes and structural alterations. The most common chromosomal aberrations were +8, -20/20q-, -Y, translocation, -7/7q-, +9, -5/5q-. The rate of abnormal karyotype in refractory anemia with erythroblasts (RAEB) and refractory anemia erythroblasts-transformation (RAEB-t) was much higher than in refractory anemia (RA). Patients with abnormal karyotype or higher IPSS scores had a higher risk of transformation into acute leukemia than patients with normal karyotype or lower IPSS scores (P<0.05)., Conclusion: MDS is a highly heterogenous disorder and karyotype analysis is helpful for its diagnosis and prognosis estimation.