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The power load of the smart grid fluctuates increasingly high and rapidly because of the introduction of intermittent energy, such as wind energy and solar energy. As a result, the increase of the randomly fluctuating load in the smart grid brings new challenges to the active power measurement of smart electricity meters. However, the installed power meter and the standard electricity meter are designed for a steady input signal. The traditional MA (moving average) and ⅡR (infinite impulse response) measurement algorithms are proposed for the steady situation and are thus not suitable to address the dynamic error testing and metering problems. Moreover, although some harmonic experiments have been performed that provide an overview of domestic and internal standards of electricity energy meter, there is a lack dynamic characteristics in them. Thus, it is of great theoretical significance and application value to study the dynamic measurement characteristics of the existing smart electricity meters and propose an effective dynamic measurement to improve the metering dynamic performance. To reduce the measurement error of a smart electricity meter under dynamic load power conditions, a SDPA algorithm for dynamic active energy measurement was proposed in this work. First, the dynamic response speed and dynamic error characteristics of active power of traditional MA and ⅡR low pass filter algorithm were deduced. Next, the limitations of the two algorithms for dynamic input signal were highlighted, and the influence factors were determined by theoretical analysis. Based on these results, a SDPA algorithm for dynamic measurement of smart electricity meter was proposed. The new algorithm was implemented by truncating periodically, executing piecewise point product operation and summing up the active power. In addition, the implementation method by decimation can save storage space and improve the operation speed. The theoretical and simulation results show that the SDPA algorithm can reach a lower error level in one period of response time.

The national standard method for the analysis of scandium in geological samples uses sodium peroxide to fuse samples. After the filtration and separation of the sample solution, Inductively Coupled Plasma-Atomic Emission Spectrometry (ICP-AES) is applied to determine scandium. This process is complex, moreover, large amounts of salts are brought in during the pretreatment and the accuracy of the result is not satisfactory, and the procedure is lengthy, making it unsuitable for current mineral exploration. A mixture of four-acid system, which includes nitric acid, hydrochloric acid, perchloric acid and hydrofluoric acid, to decompose geological samples has been used and is reported in this paper. The Sc was measured by ICP-AES. Hydrochloric acid of 5% is used as the solution medium. When the interference element content is lower than 2%, the interference factor correction (IEC) is applied to optimize the intensity of the spectral line and the solution is diluted appropriately to reduce the matrix effects. Through these steps, the accuracy and precision of the measurement results of scandium were improved. The detection limit of this new method is 0.0016 μg/mL, which is better than the detection limit (0.004 μg/mL) of the national standard method, and the recovery rate of this method is 97.0%-99.3% with measurement range of 0.00003%-10%. The relative standard deviation (RSD, n=6) is in the range of 0.4%-2.3%. National standard reference materials were analysed by this method, and the test results of scandium agree well with the recommended values. Unlike the alkali fusion method, the acid leaching method can avoid bringing in interfering substances. Hereby, the stability has been improved greatly by using ICP-AES to determine Sc. This method is less demanding on the regional and environmental conditions, is simple and fast and can be applied to a large number of geological samples in laboratories.

Understanding the transformation of P in polyphosphate form in the soil and its effect on P availability is the prerequisite for reasonable polyphosphate fertilizer application. A pot experiment was conducted to explore the effects of polyphosphate fertilizers and MAP on soil available-P, inorganic P transformation in soils, soil micro-nutrient availabilities of Fe, Mn and Zn. Meanwhile, the effects of different P fertilizer on rape P nutrition and PUE in both calcareous and acid soils were investigated. Compared with the MAP treatment, polyphosphate fertilizers significantly increased plant available P concentrations in calcareous soil. Soil water soluble-P and Olsen-P were increased by 19.0% and 25.4%, respectively, and soil resin-P and NaHCO3-P (high labile P) and NaOH-P (medium labile P) increased by 22.8%, 43.3% and 33.8%, respectively. Those results implied that polyphosphate could reduce the fixation of P in calcareous soil. However, there was no significant effect of polyphosphate fertilization on improving P availability and reducing P fixation in acid soil. In comparison with MAP treatment, polyphosphate treatments significantly mobilized micronutrient in soils and increased the uptake of Fe, Mn and Zn by rape plants. In the calcareous soil, the available Fe, Mn, and Zn increased by 2.1%, 16.2% and 20.8%, respectively. In acid soil, the available Fe, Mn, and Zn increased by 6.6%, 11.9% and 9.2%, respectively. In addition, polyphosphate treatments significantly increased dry mass, P uptake concentrations and P use efficiency (PUE) of rape in calcareous soil, but not in acid soil. In conclusion, polyphosphate fertilizer could significantly increase P availability and micronutrient availability, plant P nutrition and PUE, especially in calcareous soil. Thus, polyphosphate could be used as alternative of P source substituting the orthophosphate-based P fertilizer in calcareous soil. [ABSTRACT FROM AUTHOR]

In order to study the forming mechanism differences of filter cake under centrifugal force and mechanical stress, the particle size distribution of cakes from the press filter and filtering centrifuge were analyzed by stratified sampling, and the influences of feed grain-size composition on the particle distribution of cake in filtering centrifuge were studied in detail. Results indicate that the particle size distribution and moisture content in the cakes of press filter are uniform, while that of filtering centrifuge changes gradually. The nearer the particles are to the screen, the coarser the average particle size is, and the higher the cake moisture. Moreover, the feed particle size distribution influences the particle size distributions of the filtering centrifuge cake significantly. Due to the particle size distribution of cakes, it can be inferred that the specific filtration resistance in pressure filter cake is relatively uniform and can be treated as constant, but it decreases with the increase of cake radius in filtering centrifuge. It also shows that the recovery of fines smaller than screen mesh depends mainly on the cake bed structure in filtering centrifuge. [ABSTRACT FROM AUTHOR]

Objective: To study the effect of astragaloside IV (AS-IV) on NOD-like receptor protein 3 (NLRP3) inflammasome in neonatal rats with hypoxic-ischemic brain damage (HIBD)., Methods: A total of 24 Sprague-Dawley rats, aged 7 days, were randomly divided into a sham-operation group, an HIBD group, and an AS-IV treatment group, with 8 rats in each group. After 24 hours of modeling, brain tissue was collected for hematoxylin-eosin staining, yo-PRO-1 staining, and EthD-2 immunofluorescent staining in order to observe the cerebral protection effect of AS-IV in vivo. HT22 cells were used to prepare a model of oxygen-glycogen deprivation (OGD), and a concentration gradient (50-400 μmol/L) was established for AS-IV. CCK-8 assay was used to measure the viability of HT22 cells. RT-PCR and Western blot were used to observe the effect of different concentrations of AS-IV on the mRNA and protein expression of NLRP3, gasdermin D (GSDMD), caspase-1, and interleukin-1β (IL-1β)., Results: Yo-Pro-1 and EthD-2 staining showed that compared with the sham-operation group, the HIBD group had an increase in pyroptotic cells with a small number of necrotic cells, and the AS-IV group had reductions in both pyroptotic and necrotic cells. Compared with the sham-operation group, the HIBD group had significantly higher protein expression levels of NLRP3, IL-1β, caspase-1, and GSDMD ( P < 0.05). Compared with the HIBD group, the AS-IV group had significant reductions in the protein expression levels of NLRP3, caspase-1, and GSDMD ( P < 0.05). HT22 cell experiment showed that compared with the OGD group, the AS-IV group had inhibited mRNA and protein expression of NLRP3, GSDMD, caspase-1, and IL-1β, with the best therapeutic effect at the concentration of 200 μmol/L ( P < 0.05)., Conclusions: AS-IV may alleviate HIBD in neonatal rats by inhibiting the expression of NLRP3, GSDMD, caspase-1, and IL-1β.

Objective: To quantitatively analyze the effects of direct and indirect stimuli on the contraction of gastrocnemius in vivo and in vitro specimen by self-programming., Methods: All specimens were divided into four groups: indirect stimuli on specimen in vivo group ( n =12), direct stimuli on specimen in vivo group ( n =8), indirect stimuli on specimen in vitro group ( n =12), direct stimuli on specimen in vitro group ( n =8). Indirect stimuli ( via sciatic nerve) and direct stimuli (acupuncture needle piercing into gastrocnemius) (stimuli starting from 0 V, cycle 3 s, increment 0.02 V, 150 times) were acted on in vivo and in vitro sciatic nerve gastrocnemius muscle specimen respectively. The effects of electric intensity on the contraction of gastrocnemius were recorded by the experimental system of BL-420F. The data were processed and analyzed by the help of self-programming, to quantitatively obtain key parameters for a single contraction., Results: ① For in vivo specimen, compared with direct stimuli, effects of indirect stimuli were as follows: the threshold intensity, half-intensity and maximal intensity of the specimen were smaller ( P ＜0.05); the amplitude was larger, the contraction period was longer, and the rising slope was smaller ( P ＜0.05). ②For in vitro specimen, compared with direct stimuli, effects of indirect stimuli were as follows: the threshold intensity, half-intensity and maximal intensity of indirect stimuli were smaller ( P ＜0.05); the amplitude was larger, the contraction period was longer, and the rising slope was smaller ( P ＜0.05). ③Compared with in vitro specimen, there was no significant difference among all the above parameters of in vivo specimen, with either direct or indirect stimuli ( P ＞0.05)., Conclusion: There is no significant difference in the features of single contraction between in vivo and in vitro specimen with either direct or indirect stimuli. However, indirect stimuli can trigger gastrocnemius to produce single contraction more easily than direct stimuli, and the amplitude is larger than that of direct stimuli.

Understanding the transformation of P in polyphosphate form in the soil and its effect on P availability is the prerequisite for reasonable polyphosphate fertilizer application. A pot experiment was conducted to explore the effects of polyphosphate fertilizers and MAP on soil available-P, inorganic P transformation in soils, soil micro-nutrient availabilities of Fe, Mn and Zn. Meanwhile, the effects of different P fertilizer on rape P nutrition and PUE in both calcareous and acid soils were investigated. Compared with the MAP treatment, polyphosphate fertilizers significantly increased plant available P concentrations in calcareous soil. Soil water soluble-P and Olsen-P were increased by 19.0% and 25.4%, respectively, and soil resin-P and NaHCO 3 -P (high labile P) and NaOH-P (medium labile P) increased by 22.8%, 43.3% and 33.8%, respectively. Those results implied that polyphosphate could reduce the fixation of P in calcareous soil. However, there was no significant effect of polyphosphate fertilization on improving P availability and reducing P fixation in acid soil. In comparison with MAP treatment, polyphosphate treatments significantly mobilized micronutrient in soils and increased the uptake of Fe, Mn and Zn by rape plants. In the calcareous soil, the available Fe, Mn, and Zn increased by 2.1%, 16.2% and 20.8%, respectively. In acid soil, the available Fe, Mn, and Zn increased by 6.6%, 11.9% and 9.2%, respectively. In addition, polypho-sphate treatments significantly increased dry mass, P uptake concentrations and P use efficiency (PUE) of rape in calcareous soil, but not in acid soil. In conclusion, polyphosphate fertilizer could significantly increase P availability and micronutrient availability, plant P nutrition and PUE, especially in calcareous soil. Thus, polyphosphate could be used as alternative of P source substituting the orthophosphate-based P fertilizer in calcareous soil.

Objective: To evaluate the clinical effect and prognostic factors of nasopharyngeal carcinoma in 44 children and adolescents., Methods: From June 1987 to December 2003,44 children and adolescents with nasopharyngeal carcinoma were treated by radiotherapy, and some patients also received chemotherapy. Kaplan-Meier method was used for the survival rate and univariate analysis, and Cox proportional hazard model was used in multivariate analysis., Results: The 3.5 year survival rate was 84.2% and 62.3%.In the univariate analysis, clinical stage, lymph node (N) stage, radiotherapy dose and chemotherapy were significant prognostic factors of survival.In the multivariate analysis, N stage and chemotherapy were the prognostic factors in the survival rate., Conclusion: Most nasopharyngeal carcinomas belong to the advanced degree. These patients are sensitive to radiotherapy and chemotherapy. Combined modality therapy can improve the clinical effect of nasopharyngeal carcinoma in children and adolescents.