Search

This is an article in the field of metallurgical engineering. Titanium gypsum is an industrial waste residue mainly composed of calcium sulfate dehydrate when the titanium dioxide is produced by the sulfuric acid method. At present, the utilization rate of titanium gypsum is relatively low due to its high impurity content , difficulty in dehydration and poor mechanical properties of the subsequent products. A large amount of titanium gypsum stored in the open air has caused great environmental and economic stress on the titanium dioxide enterprises, which is a serious waste of land resources. In this article, the current situation and research progress of global titanium gypsum in building materials, chemical industry, agriculture and climate change were summarized. The suggestions and prospects for the effective reduction and high-quality resource utilization of titanium gypsum from the aspects of structure adjustment, technological innovation, green development, standard formulation and policy support were provided.

In order to develop high performance thermal reflective coating for asphalt pavement, this paper studied the effect of the ratio of functional fillers on thermal insulation performance, the effect of the ratio of binder materials on bond strength and the effect of the content of functional fillers on thermal insulation performance and bond strength, and then prepared the thermal reflective coating and evaluated its durability. The results show that, under different mass ratios of TiO2 and SiO2, the thermal insulation performance of the thermal reflective coating increases with the increase of TiO2 mass ratio. Under the same dosage of curing agent, the maximum bond strength is obtained when the dosage of toughening agent is 20%-30%. With the same amount of toughening agent, the maximum bond strength is obtained when the amount of curing agent is 30%-40%. With the increase of the content of functional fillers, the thermal insulation performance of the thermal reflective coating increases, and the bond strength decreases slowly at first and then rapidly. The thermal reflective coating was prepared according to the optimum ratio of each component. The wear rate of the coating increases with the increase of wear times, and the increase rate is fast in the early stage. The thermal insulation performance decreases linearly with the increase of wear rate. With the increase of wear times, the skid resistance first increases rapidly and then decreases slowly. [ABSTRACT FROM AUTHOR]

The current sensor based on Giant Magnetostrictive Material（GMM）and Fiber Bragg Grating（FBG）has the advantages of optical current sensor.In this paper,a sensor probe is formed by combining FBG and GMM using home-made epoxy glue.The static operation point of sensor is changed by adding a bias magnetic field.Ferrite material with good high-frequency performance is used as magnetism-guided loop to confine and send the magnetic field into the sensor probe.The magnetic field is generated by the alternating current.Then the change of current is turned into the wavelength shift of FBG.Thus the current measurement can be realized through the FBG demodulation system.Static and dynamic responses of the sensor are tested experimentally.The experimental result shows that the proposed method can effectively measure the current.

Objective: To construct a secretory eukaryotic expression vector of DSG2 fused with the Fc region of the human IgG, to validate its expression in 293T cells, and to purify the secretory protein with biological activity. Methods: The DSG2 extracellular domain fragment gene (DSG2ex), was amplified by PCR, and was inserted into the eukaryotic expression plasmid pCMV3-IgG1 to construct the recombinant eukaryotic expression plasmid-pCMV3-DSG2ex-IgG1. The successfully constructed eukaryotic expression plasmid was transfected into 293T cells to express and secrete DSG2 extracellular domain protein. The targeted protein was purified from the cell culture supernatant by Protein A affinity chromatography and confirmed by Western Blotting and ELISA. Results: The pCMV3-DSG2ex-IgG1 eukaryotic expression plasmid was successfully constructed. The highest protein expression level was obtained with 293T cells after 96 h of transfection. The relative molecular mass of the purified product was between 100 and 130 kDa estimated by SDS-PAGE, which was consistent with the expectation. The yield of the purified protein reached 0.8 mg/mL with a purity over 90%. The purified DSG2 extracellular domain protein with IgG1 tag was recognized by IgG monoclonal antibodies by Western blotting. Moreover, the ELISA results showed that the prepared DSG2 extracellular domain protein had significant binding activity to human type 55 adenovirus Fiber Knob protein (HAdV-55).Conclusion: A simple and efficient method for eukaryotic expression and purification of human soluble DSG2 extracellular domain protein was successfully established, and biologically active DSG2 extracellular domain protein was purified, which laid the foundation for the later study of its protein function and anti-adenovirus drugs. [ABSTRACT FROM AUTHOR]

Taking the analytical results of nuclear magnetic resonance as the standard, the hydroxyl content in hydroxyl silicone oil with different specifications were compared by infrared spectroscopy and reaction gas volume method. The results show that both methods can measure the hydroxyl content accurately, are also suitable for testing the hydroxyl content of low-viscosity hydroxyl-terminated vinyl silicone oil and hydroxyl fluorosilicone oil. The dispersion degree of infrared spectroscopy is smaller than that of reactant by gas volume method. [ABSTRACT FROM AUTHOR]

Objective To investigate the features of clinical phenotype and gene mutation of progressive myoclonic epilepsy (PME). Methods and Results The main clinical features of a 43-year-old man were photosensitive seizures, progressive cerebellar ataxia and peripheral neuropathy. Skeletal muscle biopsy showed typical ragged - red fibers (RRF), large amount of mitochondria accumulating under the muscular membrane, and tubular or concentric mitochondrial cristae. A heterozygous c.8344A > G mutation of mitochondrial DNA (mtDNA) was identified from peripheral whole blood cells. The final diagnosis was myoclonic epilepsy with ragged-red fibers (MERRF). Conclusions PMEs are a group of disorders with similar clinical presentations and individual characteristics. The diagnosis of PME should be considered by analyzing the clinical features, pathological results and gene detection. MERRF presents highly clinical heterogeneous features. [ABSTRACT FROM AUTHOR]

Objective To evaluate the efficacy and safety of cyclophosphamide as a second-line drug in the treatment of children with anti-N-methyl-D-aspartate receptor (NMDAR) encephalitis. Methods Six children with anti-NMDAR encephalitis, who showed poor response to steroids and intravenous immunoglobulin, were given cyclophosphamide as a second-line immunotherapy. Follow-up was performed to evaluate the efficacy and safety of cyclophosphamide. Results After first-line immunotherapy for 1-4 weeks, the six patients had reduced psychiatric symptoms, seizures, and involuntary movements; three patients had an improved level of consciousness and were able to make simple conversations. However, all the patients still showed slow response, as well as cortical dysfunction symptoms such as aphasia, alexia, agraphia, acalculia, apraxia, and movement disorders. The six patients continued to receive cyclophosphamide as a sequential therapy. They were able to answer simple questions 7 days after treatment. Three school-aged patients were able to make simple calculation, had greatly improved reading and writing ability, and almost recovered self-care ability 2-3 weeks later. The cognitive function of the six patients was almost restored to the level before the onset of disease, and their living ability returned to normal 2-3 months later. During the treatment period, there were no adverse reactions or abnormal results of routine blood test and liver and kidney function tests. Conclusions Children with anti-NMDAR encephalitis should be given appropriate immunotherapy as soon as possible. Cyclophosphamide as a sequential therapy has good efficacy and safety. [ABSTRACT FROM AUTHOR]

Under the guidance of the simulation of antigen-antibody recognition in biological mechanisms of the immune system, based on the artificial immune algorithm, a prediction model for slope stability was introduced. The slope stability sample set was defined as antigen set, and the influence factors of slope stability were defined as the antibody. Through reiteration of genetic manipulation on the antigen gene segment, the antibody set that can perform slope stability well was developed. The affinity between prediction sample set and antibody set were calculated, and the KNN algorithm was used to predict the sample stability. The self-adaptive artificial immune algorithm was also employed to improve the model effectiveness and reliability. The case study confirms that self-adaptive artificial immune algorithm has a more accurate prediction than basic artificial immune algorithm, proving that the self-adaptive approach is effective. The new method can avoid from building complex non-linear function between influence factors and stability, effectively reduce the modeling complexity and has better adaptability. [ABSTRACT FROM AUTHOR]

A study about the influence factors on effective thrust of pulse detonation engine (PDE) is carried out to obtain effective thrust. The continuous detonation combustion of air-breathing/gasoline-air PDE is achieved by using the cyclone-type aero-valves in a detonation tube with diameter of 60 mm. The effects of the filling speed of detonation tube and the stamping flow speed on the drag of PDE are analyzed based on the cold-state experiments, while the pressure P3 of the aero-valve is studied in the thermal-state experiments. The results of calculation for the thrust and drag in a period show that PDE can output effective thrust at the frequency of 10 Hz, but this effective thrust is difficult to be measured under actual working conditions. The research on the continuous effective thrust for PDE indicates that the operating frequency, detonation intensity, internal and external drag are the decision factors, while reducing the spoiler drag is the key to obtain the effective thrust. [ABSTRACT FROM AUTHOR]

A hydroponic experiment was conducted to study the effects of applying 100% NO3--N,100% NH4+-N, and 75% NO3--N+25% NH4+-N on the nitrogen metabolism and the nitrate reductase (NR) and glutamine synthetase (GS) gene expression of cherry tomato during its fruit development. Applying 75% NO3--N+25% NH4+-N slightly increased the single fruit mass, and increased the fruit NH4+-N, total amino acid, and total N contents and N accumulation significantly, compared with applying 100% NO3--N. In treatments 100% NO3--N and 75% NO3--N+25% NH4+-N, the fruit NR activity and its gene expression had no significant difference, but were higher than those in treatment 100% NH4+-N. The fruit GS activity was significantly higher in treatment 75% NO3--N+25% NH4+-N than in treatment 100% NO3--N. In the three treatments, isozyme GS1 (Cytosolic type GS) and GS2 (Chloroplast type GS) expression was inconsistent with GS activity, suggesting that the effects of applied N on GS activity could be mainly reflected at posttranscriptional level. [ABSTRACT FROM AUTHOR]

The main procedures of the streamer breakdown of gas gaps were reviewed, and the dielectric fluid breakdown procedure of powder-mixed electrical discharge machining (EDM) was analyzed by means of the streamer theory. Considering the particle as an in-between electrode in series with the workpiece and tool electrode > the interelectrode gap can be divided into two sections. In each section, streamers can occur and expand rapidly, and the breakdown of the dielectric fluid is accomplished simultaneously. Thus the discharge channel connects the electrode couple via some certain particle and series-discharging is then conducted. According to the analytical results, the shape of the discharge channel was subsequently deduced combining with some experimental phenomena. The single-channel discharge model is accepted rather than the multi-channel discharge model. The bettering of the machined surface roughness is on account of the over expansion of the plasma channel radius near the anode which causes a decrease in the local energy density at the anode surface. [ABSTRACT FROM AUTHOR]

Traditional personnel-job matching methods assume that personnel capacity is homogeneous, which can not reflect the needs of adopting strengths and avoiding shortcomings. Based on the difference of human capital inner quality, respecting personnel individual strength characteristics, "four in one" personnel matching method based on human capital advantage structure is constructed. According to group job comprehensive indicator system, from the starting point of human capital advantage structure identification method which can describe relative comparative degree of strengths and shortcomings, job human capital ideal structure is formed according to comprehensively considering the human capital of international level, domestic level, organizational level, personnel human capital advantage structure is formed according to comprehensively analysis of self identification and others' identification. Taking difference degree of advantage structure as point of penetration, personnel-job matching decision is made from the point of whole optimization. The advantage of the method is reflecting "human oriented" and development, maximizing personnel advantages. The calculation example shows the feasibility and validity of the method. [ABSTRACT FROM AUTHOR]