Search

A kind of pyroshock reduction device of honeycomb sandwich plate is designed,which takes the impact as the research object when satellite deploys the solar array. The dynamic model of shock response and the key points in design are explained in detail from the view of vibration reduction. Spring element was introduced to improve the honeycomb sandwich plate and its accessory structure,then,the shock characteristics of the system wartested. Dynamic response of satellite after setting the damping device was analyzed. The result indicates that the honeycomb sandwich plate on mounting plate can effectively reduce shock response,and meet the launching condition,so the design is reasonable.

It is very important to identify manganese ore and manganese smelting slag for manganese ore import trade and environmental protection. Due to the similarity of elements in manganese smelting slag and some manganese ore, such as Mn, Si, Al, Mg, Ca and other impure elements, they cannot be identified only by the content of the elements. China's main imported manganese ore and the main manganese smelting slag samples were chosen as the research subject, which was studied by X-ray Fluorescence Spectrometry(XRF), X-ray Diffraction(XRD) and Fourier Transform Infrared Spectroscopy(FTIR). The silicon content of the manganese slag is relatively high, whereas the calcium content of the water quenching slag and air cooling slag are relatively high. The phase characteristics of manganese ore include pyrolusite, manganese oxide, bixbyite, rhodochrosite, among others. The phase characteristics of manganese smelting slag include iron silicate and tephroite because of being smelted. The characteristics of infrared absorption show that manganese ore has two strong absorption bands in the range of 600-400 cm-1, and dependently or at the same time has infrared characteristic peaks at 1420 cm-1. Manganese smelting slag has widely strong infrared characteristic peaks at around 960 cm-1. The phase spectrogram database of imported manganese ore and manganese smelting slag in China has now been established. Primary differences between the manganese ore and smelting slag were determined ultimately, and were proved by FTIR.

Heavy metal elementals can be enriched in soil at mineral products yard, which become a problem of environmental pollution caused by elemental migration, transformation and circulation in underground water. In this experimentation the modified BCR sequential extraction method was applied to the chemical species analysis of Cd, As and Pb. Based on the properties of these three elementals, the chemical species of Cd, As and Pb were divided into four fractions: exchangeable, reducible, oxidizable and residual, and Inductively Coupled Plasma-Atomic Emission Spectrometry (ICP-AES) were used to measure the content of Cd, As and Pb. Morphological analysis standard reference material GBW 07436 was conducted to verify the accuracy of the three step extraction state. Contents of chemical species of Cd, As and Pb in soil from six mineral products yard were analyzed, including contents of three step extraction state plus the residual and the total contents of the desired metals elements. The recoveries were from 84.54% to 102.88%. The analysis results for actual samples demonstrated the contents of Cd, As and Pb in non-residual fraction were in order as Cd (79.40%-94.94%)>Pb(24.27%-37.73%)>As (22.89%-31.51%), which indicated Cd is easy to enter the biosphere. This method has resolved the problem to extract the chemical species of heavy metal elements in soil from port mineral products yard, and has profound significance to the treatment of contaminated soil.

In the batch analysis of manganese content in manganese ore with artificial titration method, it consumes a large amount of manual labor. With the popularity of automatic potentiometric titrator, it is possible to complete the volumetric titration using the instrumental equipment. The manual titration is conversed to the automatic potentiometric titration is the urgent study subject to be solved. In the paper, a method for the determination of manganese content in manganese ores with automatic potentiometric titration was established. The related titration parameters and the equivalence point identification standards is identified. Manganese ore sample was decomposed with hydrochloric acid and phosphoric acid, the carbon and organic matters in the sample were removed with nitric acid, then the sample solution was prepared with perchloric acid. In the experiment, at first, the platinum composite electrode was indicator electrode, the oxidation and reduction titration was made for the pre-pipette potassium dichromate standard solution and the blank solution with ferrous ammonium sulfate standard solution, the concentration of ammonium ferrous sulfate standard solution was calculated. Then, the oxidation and reduction titration was made for the sample blank solution and sample solution, the content of manganese was calculated. The detection range of the method for manganese is 5%-60%. The method was used to the determination of national standard reference materials, the accuracy and precision were high. A plurality of ore samples with different level of manganese from different mine area were determined using this automatic titration method, the analytical results had no significant difference with manual method by t-test. Titration method and high degree of automation, methods of robust, suitable for smelting enterprises, the port inspection and other industries, has the value of popularization. The automatic titration is robust, and is suitable for ore analysis in smelting enterprises and port inspection.

Determination of trace elements in minerals usually requires pre-concentration and separation with many spectral line interferences during measurement. The concentrate ores were calcined at high temperature to remove the C and S. The calcinates were then digested by using the HCl-auqa regia-HF acids system. The D290 anion exchange resin and activated charcoal procedures were conducted to enrich Pt and Pd. The contents of Pt and pd were obtained by Inductively Coupled Plasma-Mass Spectrometry (ICP-MS) with internal standard elements of Y, In and Bi and measured isotopes of 105Pd and 195Pt. The absorption property and separation conditions of D290 anion exchange resin to trace Pt and Pd in copper concentrate ores were studied. The enrichment effects of Pt and Pd were above 90%, the recoveries were 92.0% and 96.0%, and the relative standard deviations (RSD, n=6) were smaller than 4%. The detection limits of the method were 0.126 ng/g and 0.105 ng/g for Pt and Pd. The presented method mostly reduced the inferences from other ions to the target elements of Pt and Pd. Moreover, the collision reaction between the internal standard elements and high purity Ar effectively reduced the matrix effect and isobaric interference. Five random geological samples were analyzed by this method in comparison with the method of NiS fire assay ICP-MS and the established method had the advantages of simple pretreatment and high enrichment of Pt and Pd with lower detection limits.

CTNNB1, encoding β-catenin protein, is the most frequently altered proto-oncogene in hepatic neoplasms. In this study, we studied the significance and pathological mechanism of CTNNB1 gain-of-function mutations in hepatocarcinogenesis. Activated β-catenin not only triggered hepatic tumorigenesis but also exacerbated Tp53 deletion or hepatitis B virus infection-mediated liver cancer development in mouse models. Using untargeted metabolomic profiling, we identified boosted de novo pyrimidine synthesis as the major metabolic aberration in β-catenin mutant cell lines and livers. Oncogenic β-catenin transcriptionally stimulated AKT2, which then phosphorylated the rate-limiting de novo pyrimidine synthesis enzyme CAD (carbamoyl-phosphate synthetase 2, aspartate transcarbamoylase, dihydroorotase) on S1406 and S1859 to potentiate nucleotide synthesis. Moreover, inhibition of β-catenin/AKT2-stimulated pyrimidine synthesis axis preferentially repressed β-catenin mutant cell proliferation and tumor formation. Therefore, β-catenin active mutations are oncogenic in various preclinical liver cancer models. Stimulation of β-catenin/AKT2/CAD signaling cascade on pyrimidine synthesis is an essential and druggable vulnerability for β-catenin mutant liver cancer.

The communication middleware of the yacht supervision management system (YSM) which is based on the DDS is the communication management software of the yacht supervision center system and the ship monitoring system. In order to ensure the high efficiency and high reliability of communication middleware, the paper for the first time introduced DDS communication framework to the yacht supervision system in the process of software design and implementation, and designed and implemented more flexible and reliable communication management interface for the DDS communication framework. Through practical test, each performance index of DDS communication middleware software of the yacht supervision management system has reached the design requirements.