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The precise control of nitrogen content of high nitrogen stainless steel is the key control factor of production. Taking Mn18Cr18N high nitrogen steel as an example， this paper studies the relationship between steel composition， temperature， nitrogen pressure and nitrogen content control in pressure induction melting process by using metallurgical principle， factage thermodynamic software and thermal state experiment and detection analysis methods.The results show that the reliability of the "composition temperature pressure" relationship equation based on the theoretical data is high， and the theoretical and predicted values of nitrogen pressure in the three heats experiment are in good agreement with the actual control values. The thermal experiment finds that when the contents of Mn and Cr remain unchanged， increasing the nitrogen partial pressure can increase the N content in the ingot， but when the nitrogen reaches about 1%， the effect of increasing the nitrogen content by increasing the nitrogen partial pressure decreases.When the content of Mn or Cr is low， the nitrogen content can be increased by increasing the nitrogen partial pressure. Reducing the content of C and Si in steel is beneficial to the alloying and stable control of high nitrogen content in steel. It is advisable to control the melting temperature of the pressure furnace at 1 500-1 550 ℃ and the nitrogen pressure at 0.225-0.325 MPa when the nitrogen content in Mn18Cr19N steel is necessary to be controlled ≥ 0.8%.

Additive manufacturing provides a new way to develop high-performance superalloys and components. A γ′- strengthened CoNi-base superalloy suitable for additive manufacturing was developed，and a crack-free block material was prepared by optimizing the parameters of electron beam melting（EBM） technology. The experimental results show that the lowest porosity of the alloy is about 0.14% when the scanning speed is 2000 mm/s. The microstructures of the as-printed CoNi-base alloy are columnar grains growing along the direction，the average grain width is about 235 μm，and the volume fraction of γ′ phase is about 30%. After hot isostatic pressing and solution aging treatment，the porosity of the alloy is further reduced to about 0.09% with unobvious change of columnar grains. The average size of γ′ phases is about （70±18）nm with the volume fraction of about （32±3.6）%. The results of room temperature tensile tests show that the additive manufactured γʹ-strengthened CoNi-base superalloy exhibits excellent strength and ductility，showing a good potential of industrial application.

In the engineering practices of coal seam mining and gas drainage, the unloading damage of soft and hard composite coal seam is a common problem faced by surrounding rock support and coal seam enhancement. In order to explore the mechanical properties of the composite coal seam during the unloading process and the energy evolution law during the failure process, based on the energy dissipation equation and the coal rock damage model, we applied PFC numerical simulation and laboratory tests, and studied the deformation and failure modes of coal, mechanical properties and energy dissipation and acoustic emission laws of Xintian coal body under the layered thickness; finally, the control law of unloading failure of 4# soft and hard composite coal seam thickness ratio in Xintian Coal Mine is obtained and verified by hydraulic punching on site. The results show that: under triaxial compression, the effect of different thickness ratios on the deformation and failure modes of the composite coal body can be seen in the transference of the fracture zone, the stress-strain curve of the composite coal body taking the thickness ratio of 0.45 （soft layer thickness/composite coal seam thickness） as the dividing point causes a “stepped” smooth and violent change, which is related to the size of the confining pressure; the essence of the unloading failure of the composite coal body is the fracture of the bonding bonds between the particles. What’s more, the size and the breaking of the cohesive bonds between the coal particles have a positive effect. The results of in-situ hydraulic punching are consistent with the simulation results.

One of the primary issues in building a digital mine is to build a high-quality information network with low latency, large bandwidth, and high reliability. Traditional wireless communication technologies such as WiFi and 4G have been unable to meet the new demand of the digital transformation of mines. Starting from the demand for communication networks in digital mines, the necessity and deployment difficulties of 5G technology in underground mines are studied. It is pointed out that the underground 5G networking scheme based on centralized-radio access network (C-RAN) can effectively reduce the deployment requirements and difficulties of 5G networks in underground mines. However, two issues, the high consumption of optical fiber resources and the difficulty in managing dumb resource failures, must be addressed. A digital mine all-optical network system based on 5G C-RAN technology is proposed. The system architecture is introduced from three levels: C-RAN access network, high-speed all-optical network, and intelligent control platform. Key technologies such as semi-active optical network architecture, low-cost wavelength division multiplexing (WDM) high-speed transmission, and intelligent control platform are studied. The system uses direct inspection WDM technology to save optical fiber resources, which can reduce the number of optical fibers used by 91.67%. At the same time, based on semi-active architecture and topping operation administration and maintenance (OAM) technology, it achieves low-cost control and flexible deployment of optical fiber networks. It solves the tight optical fiber resources and optical fiber network management challenges in underground roadways. The experimental results show that the transmission optical power of 12 WDM optical modules with different wavelengths is 3.5 dBm to 5.2 dBm. The reception sensitivity is −16.9 dBm to −19.0 dBm, and the link budget capacity can reach over 21 dB, meeting application requirements. The extinction ratio ranges from 4.7 dB to 5.1 dB, and the eye pattern margin is greater than 17.5%, indicating high signal quality. At a low temperature of − 40 ℃ and a high temperature of 85 ℃, the WDM optical module has some performance degradation in both transmission optical power and reception sensitivity. But it can still meet the transmission requirements of 10 km. Field application results show that the transmission optical power of 12 WDM optical modules with different wavelengths is 3.7 dBm to 5.6 dBm, and the reception sensitivity is −17.9 dBm to −16.3 dBm. The link budget capability of the worst channel is still above 20.2 dB, meeting application requirements.

ObjectiveTo investigate the impact of antipsychotics on serum uric acid level in patients with schizophrenia， and to clarify the antioxidant properties of antipsychotics， so as to provide evidence-based guidelines for the treatment of schizophrenia.MethodsKeywords combined with free-text search strategies were used to retrieve English and Chinese databases including PubMed， Embase， Web of Science， Cochrane Library， CNKI， Wanfang Database， VIP database and Chinese Biomedical Literature Database. Randomized controlled trials related to the effects of antipsychotics on serum uric acid level in patients with schizophrenia were included. Meta-analysis was performed using RevMan 5.3.ResultsA total of 9 kinds of antipsychotics and 1 434 schizophrenia patients in 15 Chinese and English literatures were included. Meta-analysis showed that olanzapine （MD=14.01， 95% CI： 2.39~21.62， P0.05）.ConclusionThe effect of different kinds of antipsychotics on serum uric acid level in schizophrenia patients varies， among which olanzapine and chlorpromazine can elevate serum uric acid level in patients with schizophrenia， whereas no other antipsychotics have been found to have any effect on serum uric acid level.

In order to endow cotton fabric (CF) with various properties, copper metal-organic framework (Cu-BTC) was combined with CF.Cu-BTC/CF composites were prepared by loading Cu-BTC on CF using layer by layer self-assembly method. Its adsorption, UV protection and antibacterial property were studied. The results showed that adding nano-Al2O3 and cationic surfactant 1631 during the preparation process the quantity and uniformity of Cu-BTC on CF could be improved. The adsorption decolorization rate of Cu-BTC/CF composite for methylene blue was reached 97% and could still be reached 79% after repeated use for three times. The UV protection factor (UPF value) of the Cu-BTC/CF composite was reached 100+, and the bacteriostatic rate against E.coli and S.aureus were more than 99%. It is considered that loading Cu-BTC on CF can endow CF with various functions, such as adsorption, UV protection and antibacterial. [ABSTRACT FROM AUTHOR]

Aiming at the problem of on-line detection of cylinder wall temperature in the drying process of tobacco dryer, this paper proposed a novel method named deep gated recurrent unit(DGRU)network to predict cylinder wall temperature. In order to improve sample quality, data preprocessing technologies including wavelet denoising and normalization were utilized. Then, mutual information was used to determine the optimal features as model input, which had the largest correlation with the cylinder wall temperature. Next, stacked gate recurrent unit network was introduced to extract the deep hidden nonlinear dynamic representation from thermal data, and then sent into a fully connect network to estimate the cylinder wall temperature. Finally, based on the industrial data of dryer drying process in a tobacco factory, the experiment results showed that the median and mean value of prediction error by DGRU algorithm was very close to the zero scale line, and caused few abnormal points. The method exhibited higher prediction accuracy, and could accurately predict the cylinder wall temperature. [ABSTRACT FROM AUTHOR]

A method for measuring water-soluble sodium, potassium, calcium and magnesium sulfate ions in soil was established by ICP-AES after centrifugation of 4 000 r/min using polyethylene oxide as flocculation. On the basis of the conventional extraction method, with the addition of the polyethylene oxide flocculant, it makes the colloid in the solution form flocculant to agglomerate and get clear solution, which eliminates the interference of colloid on the adsorption of potassium, sodium, calcium and magnesium. The established ICP-AES method for the determination of potassium, sodium, calcium and magnesium sulfate is simpler and faster than the traditional method, which have high accurate and reliable results. The detection limit is 0.37-3.0 mg/g, and the relative standard deviation is less than 5. 6%. The result fully meets the detection requirements. This method is simple, rapid, practical and has no secondary pollution to the environment. It has been successfully applied to the determination and analysis of water-soluble potassium, sodium, calcium, magnesium sulfate ions in soil, and is suitable for batch analysis of soil samples. [ABSTRACT FROM AUTHOR]

After extraction of volatilization hydroxybenzene by alkali in sediment, owing to the turbid solutionand interference, directly detect the content by using flow injection analyzer, it is easy to plug the instrument piping, and affect the subsequent determination. Therefore, the extracting was distilled by adding copper sulfate in a fully automatic the inteliigent integrated distiller under acidic conditions to eliminate the interference, and the volatilization in the bottom sediment was determined by automatic flow injection analyzer. The addition amount of phosphoric acid and copper sulfate, shaking time, disttilation power and volume were optimized f the method which is excess phosphoric acid of 5 mi,adding 5 g copper sulfate, shaking time of 10 min, distillation power of 50 W and distillation weight of 225 g were determined. The linear correlation coefficient was above 0. 999 9. The receives were in the range of 89. 3% -103%. The detection limit was 0. 03 mg/kg. The result of the experimental method is consistent with the traditional specfrophofomefsic method,which Is not body automatic, but also friendly to the environment and people [ABSTRACT FROM AUTHOR]

A method for the determination of diethylstilbestrol (DES), hexestrol (HEX) and dienestrol (DS) residues in drinking water was established by on-line solid phase extraction (SPE) coupled with high performance liquid chromatography (HPLC). The material synthesized on the base of sol-gel technology was employed as adsorbent. This material was prepared using 3-aminopropyltriethoxysilane (APTES) as the functional monomer, tetraethoxysilane (TEOS) as the crosslinking agent, and acetic acid as the initiator. The synthesized adsorbent showed outstanding property for the estrogen extraction. The estrogen can be caught effectively from water samples and the extraction can be achieved rapidly. Some important parameters, such as pH of sample solution, eluent solvents, loading flow rate, which might influence extraction efficiency, were optimized. The results indicated that the limit of detection (S/N = 3) of the developed method could reach 0.07-0.13 microg/L under the conditions of pH 7.0 of sample solution, methanol and 1% (v/v) acetic acid aqueous solution as the eluent solvent and the loading flow rate of 2 mL/min. The recoveries of the three estrogens from the water samples at three spiked levels ranged from 82.31% to 99.43% with RSD of 1.61%-7.15%. The method was simple, rapid, and suitable to detect the trace residues of estrogens in drinking water.