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Nitrogen-doped mesoporous carbon（NMC） was synthesized using hard-template，and was characterized using specific surface area analyzer，transmission electron microscope，Fourier transform-infrared spectrometer and X-ray photoelectron spectroscopy. NMC was applied in the adsorption of Pb（Ⅱ） in two different tunnel construction wastewaters，and the effects of pH，reaction time on adsorption and its adsorption kinetics models and sorption isotherms were investigated. The results showed that the adsorption kinetics was best described by pseudo-second-order model，and its adsorption characteristics conformed to the Langmuir and Temkin model. According to the results of the experiments and characterization，Pb（Ⅱ） adsorption by NMC involved physisorption such as electrostatic interaction and pore diffusion and chemisorption like chelation with functional groups. The estimated maximum adsorption capacity based on Langmuir model was 493.5 mg/g and 603.9 mg/g，respectively for the two wastewaters. In addition，NMC could be regenerated and reused by treatment with HCl.

This paper digs out the corresponding influencing factors by defining the traditional music communication effect. For research purposes, the questionnaire is analyzed to analyze the impact of traditional music communication from an Internet perspective. Two distribution methods, online and offline, are used to collect research data. The data are analyzed based on the Pearson correlation coefficient and multiple regression model, after testing the reliability of the questionnaire. The music form scored the highest, with a mean of 20.70 and a standard deviation of 12.09, and it had the greatest influence on the traditional music dissemination process. There is a significant positive correlation between music content, music form, creator, communicator, audience, and communication media and traditional music communication effect, P

This study used the historical and cultural block of Taiping Street in Changsha as the research object. First the current microclimate environment of the street space was analyzed, then numerical simulations based on ENVI-met software were performed, which compared the microclimate numerical simulation results of three typical greening optimization schemes of the street space in the study area and the benchmark scheme, as well as explained the degree of thermal environment control of the greening optimization scheme. This study is expected to provide a reference for the reconstruction of urban historical blocks as well as optimization and control of the thermal environment. The results showed that: 1) With an hourly change in solar radiation, the thermal environment changed considerably, and the horizontal spatial distribution was characterized by "high temperature and low humidity" and "low temperature and high humidity." Thermal comfort is related to the underlying surface conditions, wind environment, building layout, and other factors. The low temperature and high humidity of the area with relatively concentrated green space along street spaces had a slow-release effect on the thermal environment. The ventilation effect of the area with the dense building layout was poor, and the thermal radiation of the underlying surface was high, affecting the heat dissipation and humidification in the research area. 2) The enclosed space layout of buildings in the study area caused building shadows and poor ventilation to affect the green space, which was not conducive for cooling and humidification. 3) Three types of greening transformation schemes were proposed for the street spaces of three different architectural layouts in the historical block of Taiping Street. The three kinds of street space green space optimization and benchmark schemes (the current street space situation) were simulated using ENVI-met microclimate simulation software. Optimization results showed that the same greening optimization scheme had different regulatory effects on the thermal environment in different building layouts. The three kinds of street spaces significantly reduced the average radiation temperature of the block by increasing the greening area of the block. The optimal regulatory effect of the thermal environment of the tree-shrub+three-dimensional (water) compound green space type was better than that of the tree-shrub and tree-grass scheme in the daytime. Under a certain green space ratio, the area of shade generated by the uniform and decentralized layout of green space in a commercial space covered the largest range of street space. The order of the degree of thermal environment optimization and control was decentralized>parallel>centralized. The residential and square spaces were affected by the architectural layout, and the green space layout should have good ventilation, cooling, and humidification effects; therefore, the maximum degree of thermal environment optimization and control is the centralized layout.

The phenomenon of plagiarism in coursework is common among college students. This phenomenon seriously affects the quality of higher education. The school has developed a series of homework similarity checking models to ensure the originality of English teaching coursework. The fractional differential equation method is used to classify and analyze the assignments with plagiarism suspicion. The article calculates program similarity’s fractional differential equation calculation by sequence matching algorithm in English homework. Finally, we extract AST features of similar program parts and generate spatial vectors. The research aims to find out plagiarized assignment texts by cluster analysis. Experimental research shows that the establishment of this model can assist English teachers in checking online homework. At the same time, the model can also help improve the efficiency of teachers’ homework checking.

ObjectiveTo investigate the influencing factors of hyperuricemia （HUA） among children and adolescents， and provide evidences for early intervention.MethodsFrom 2016 to 2017， a multi-stage stratified random sampling method was used to select three urban and rural sites in Chongqing， and some students aged 7~17 years were selected to conduct questionnaires， physical measurements and laboratory tests. Factor analysis was used to analyze dietary patterns. Regression and classification tree models were used to explore the influencing factors of HUA.ResultsA total of 1 544 students were enrolled in the study. The prevalence rate of HUA was 19.49% which was higher among male and elder students. Four common dietary patterns including meat and vegetable/fruit， snacks， cereal/potato/bean/nut and staple were included in the factor analysis， and the contribution rate to total variance was 42.641%. Scores of each pattern were divided into four ranking （Q1~Q4） from low to high. The results of univariate regression showed that participants with the fourth quartile （Q4） score of meat and vegetable/ fruit pattern had a higher risk of HUA （OR=1.687） compared to those with the first quartile （Q1） score， while the odds ratio was 1.764 in staple pattern； participants with the Q4 score of bean/nut pattern had a lower risk of HUA （OR=0.588） compared to those with Q1 score. After adjusting for confounding factors of monitoring area， gender， age， waist circumference， BMI， blood lipids， blood sugar and physical activity， participants with Q4 score had a lower risk of HUA （OR=0.638）compared to those with Q1 score in cereal/potato and bean/nut pattern. Classification tree model showed that age， gender and BMI level were the main influencing factors of HUA among this group.ConclusionThe prevalence of HUA in children and adolescents aged 7~17 years in Chongqing was high. Strong attention should be paid to the incidence of HUA among boys， especially aged 12 years and above， overweight and obese， and the dietary pattern of cereal/potato and bean/nut pattern should be encouraged.

C18H27N5O6, monoclinic, P21/n (no. 14), a = 11.6588(12) Å, b = 7.0645(6) Å, c = 25.700(3) Å, β = 94.899(3)°, V = 2109.0(4) Å3, Z = 4, Rgt(F) = 0.0630, wRref(F2) = 0.1632, T = 273 K.

Reservoir computing (RC), a particular form of recurrent neural network, is under explosive development due to its exceptional efficacy and high performance in reconstruction and/or prediction of complex physical systems. However, the mechanism triggering such effective applications of RC is still unclear, awaiting deep and systematic exploration. Here, combining the delayed embedding theory with the generalized embedding theory, we rigorously prove that RC is essentially a high-dimensional embedding of the original input nonlinear dynamical system. Thus, using this embedding property, we unify into a universal framework the standard RC and the time-delayed RC where we introduce time delays only into the network's output layer, and we further find a trade-off relation between the time delays and the number of neurons in RC. Based on these findings, we significantly reduce the RC's network size and promote its memory capacity in completing systems reconstruction and prediction. More surprisingly, only using a single-neuron reservoir with time delays is sometimes sufficient for achieving reconstruction and prediction tasks, while the standard RC of any large size but without time delay cannot complete them yet.

BACKGROUND The extractable state of soil heavy metal elements is an important index to measure their bioavailability, but its content changes with soil acid-base properties and other environmental conditions. When determining which method to use for the extractable state of soil heavy metal elements, there are more than 7 kinds of extraction reagents involved in relevant standard methods or technical specifications. These include hydrochloric acid of pH=5.8, 0.1mol/L hydrochloric acid, 0.43±0.02mol/L nitric acid, 0.11mol/L acetic acid, 1mol/L ammonium nitrate solution, 0.005mol/L DTPA leaching agent, 0.01mol/L calcium chloride solution. Different scholars have different research conclusions on different extractants. There is no systematic research report on extractants suitable for different soil types. OBJECTIVES To select and determine the general extractant suitable for the extractable state of heavy metal elements in soil with different acid-base properties. METHODS Using typical farming soil samples as the research objective, 7 kinds of extracting agent were used to extract 8 heavy metals (Cd, Ni, Cu, Zn, Cr, Pb, As and Hg). Inductively coupled plasma-mass spectrometry (ICP-MS) was used to determine Cd, Cr, Cu, Pb, Zn, Ni, whereas atomic fluorescence spectrometry (AFS) was used to determine As and Hg. The extraction rates of 7 kinds of extractants were compared, and the effects of soil acid and alkali properties on the extraction rate of heavy metal elements were studied. RESULTS Dilute acid solution had a strong ability of leaching heavy metals from soil, and it was not related to the acidity and alkalinity of the soil. Although the extraction ability of 1mol/L ammonium nitrate solution for cadmium indicated that the activity of cadmium in acidic soil was much higher than that in alkaline soil, its extraction rate of lead in alkaline soil was higher than that of cadmium. The extraction rate of DTPA extractant for soil heavy metal elements was significantly higher than that of 0.01mol/L calcium chloride solution, especially for lead, copper and zinc. Moreover, the extraction rate of DTPA extractant for soil heavy metal elements did not change significantly with soil acid-base properties. 0.01mol/L calcium chloride solution had the highest extraction rate of cadmium in soil, which was closely related to the acid-base properties of soil. CONCLUSIONS 0.01mol/L calcium chloride solution is an ideal general extractant for the extractable state of soil heavy metal elements.

C19H15N5O·H2O, triclinic, P1‾$P\overline{1}$ (no. 2), a = 9.1132(7) Å, b = 9.6788(9) Å, c = 11.0964(10) Å, α = 65.796(3)°, β = 79.406(3)°, γ = 87.484(3)°, V = 876.96(13) Å3, Z = 2, Rgt(F) = 0.0482, wRref(F2) = 0.1405, T = 273(2) K.

ObjectiveTo determine the association of dietary diversity and dietary pattern with cognitive function in elderly in community.MethodsA cross-sectional study was conducted to randomly select 143 elderly people over 65 years old in Wangdingdi Community of Tianjin. Self-designed questionnaire was used and then dietary diversity index was calculated. Wechsler Adult Intelligence Scale-Chinese Revised （WAIS-RC） was used to measure intelligence quotient （IQ） to assess cognitive function. Factor analysis and multivariate linear regression model were used to extract dietary patterns and determine the association of dietary diversity index and dietary patterns with cognitive function， respectively.ResultsFactor analysis revealed four dietary patterns， which were meat and cereal dietary pattern， fish and poultry milk dietary pattern， bean vegetable dietary pattern， and egg dietary pattern. Multivariate linear regression showed that egg dietary pattern was significantly associated with performance IQ （P0.05）.ConclusionEgg dietary pattern may protect cognitive function in the elderly. Therefore， the elderly should increase the intake of eggs in daily diet.

Abstract A flexible circularly polarized (CP) wearable antenna is proposed for a wireless body area network at the 5.8‐GHz industrial, scientific, and medical band. The proposed antenna is made of flexible polyimide and foam material. The CP radiation is enabled by loading two pairs of shorting pins on a rectangular patch antenna. The 3‐dB axial ratio (AR) bandwidth is doubled by adding two inverted L‐shaped parasitic stubs on both sides of the antenna. For validation, the antenna with the dimensions of 0.68λ0 × 0.68λ0 × 0.044λ0 was fabricated and measured in various scenarios with an impedance bandwidth of 6.6% (5.67–6.05 GHz), an AR bandwidth of 3.85% (5.730–5.955 GHz), and a peak gain of 7.2 dBi. The measured radiation in the off‐body direction is achieved with a half‐power beamwidth of 65° and a 3‐dB AR beamwidth of 84°. With the specified input power of 100 mW, the specific absorption rates are 0.613 and 0.294 W/kg in 1‐g and 10‐g average tissues. Moreover, through analysing the link budget a reliable communication can be guaranteed within 20 m in indoor line‐of‐sight environments.

Eliminating poverty and exploiting natural resources are sustainable development goals for modern society, especially for developing countries or regions. To achieve these targets, development-oriented eco-tourism planning and design can empower rural areas with rich available natural resources to eventually achieve the aforementioned goals. Pro-Poor Tourism (PPT), an initiative proposed by the UK's Department for International Development in 1999, is regarded as an effective pathway that benefits, through tourism, the underprivileged population living in poor areas. For the purpose of attracting the participation and increasing the income of the poor population, we conducted research, in the present study, on possible models of development-oriented poverty reduction via ecotourism in forest zones. We then proposed several development paths for PPT industries in Lechang city, Guangdong province, southern China, by utilizing the literature review method and conceptual analyses and comprehensively adopting the PPT strategy. The results indicated that: 1) four stakeholders [(i.e., government departments, tourism enterprises, rural communities, and non-profit social organizations (NGOs)] are responsible for engaging the poor population, alleviating poverty, and protecting the environment in different ways. Specifically, government departments are expected to play a leading role in setting up platforms and supervising the situation, tourism can maximize its usage of various ecological resources rationally and sustainably, and the rural communities and NGOs are recommended to serve as an organic unit, working together to push forward certain PPT tasks and form practical development models. 2) In consideration of the availability of three featured types of ecological resources (i.e., natural forests, high mountain tea, and characteristic vegetables and fruits) in Lechang city, the present study put forward a compound development model of ecological tourism consisting of the above three featured agro-forestry resources.Furthermore, we proposed three possible pathways suitable for the industrial development of Lechang city; that is, (i) "leisure agriculture + characteristic forest fruit industry + e-commercial tourism industry," (ii) "understory leisure industry + understory economic industry + initial processing of forest products," and (iii) "forest eco-tourism + characteristic forest planting + natural ecological education." In conclusion, our study suggests that the rational utilization of the PPT strategy and the effective integration of government departments, tourism enterprises, rural communities, and NGOs could facilitate subsequent tasks. The study also emphasized that achieving the anticipated three goals (i.e., comprehensive development of economy, comprehensive development of poor communities, as well as poor population and ecological sustainability) might largely rely on the full consideration of benefits for the economy, society, and the environment during the process of development-oriented poverty reduction via eco-tourism by the four stakeholders.

Objective To investigate the effects of atmospheric gaseous pollutants SO2, NO2, CO and O3 on the reproductive endocrine system of male college students. Methods Established cohort of the male reproductive health in Chongqing college students (MARHCS) study. A total of 796 subjects were recruited to complete the baseline survey in 2013, and then followed up in 2014 and 2015. Their semen parameters, sperm DNA damage, and serum sex hormone levels were detected. Air pollution data and meteorological data were also collected during the study period. The mixed effect model was used to analyze the associations of exposure to SO2, NO2, O3 and CO with semen routine parameters, sperm DNA damage indexes and sex hormone levels. Results There were no significant differences in sperm motility and serum progesterone level between the 3 investigations. But statistical differences were observed in semen volume, sperm density, total sperm count, sperm motility and normal sperm morphology, and high DNA stainability (HDS) between the 3 investigations (P < 0.05). So were in the serum levels of estradiol, luteinizing hormone (LH), prolactin and testosterone. The results of the mixed effect model showed that significant negative correlations were seen in SO2 concentration with serum prolactin and progesterone levels, in O3 concentration with follicle stimulating hormone (FSH) and testosterone to estradiol ratio (T/E2), in NO2 with sperm normal morphology rate, and in CO with FSH level. After Bonferroni multiple correction, the differences were still statistically significant (corrected P < 0.05). In addition, O3 concentration was positively correlated with sperm motility (β=4.88; 95%CI: 2.60~7.22; corrected P < 0.05) and normal sperm morphology rate (β=7.28; 95%CI: 3.44~11.27; corrected P < 0.05). So were the concentration of NO2 with serum FSH, LH and testosterone levels (corrected P < 0.05). Conclusion Exposure to gaseous pollutants SO2, NO2, O3 and CO might affect the semen quality and reproductive hormone levels in young men.

C31H46N10O8, monoclinic, P2/n (no. 13), a = 8.8207(6) Å, b = 9.7818(8) Å, c = 20.9498(17) Å, β = 97.259(3)°, V = 1793.1(2) Å3, Z = 2, Rgt(F) = 0.0426, wRref(F2) = 0.1269, T = 273 K.

C26H30N8O4, triclinic, P1‾$P‾{1}$ (no. 2), a = 8.0277(6) Å, b = 11.1460(10) Å, c = 15.8921(13) Å, α = 99.439(3)°, β = 102.525(3)°, γ = 95.309(3)°, V = 1357.17(19) Å3, Z = 2, Rgt(F) = 0.0442, wRref(F2) = 0.1167, T = 273 K.

Data-based detection and quantification of causation in complex, nonlinear dynamical systems is of paramount importance to science, engineering, and beyond. Inspired by the widely used methodology in recent years, the cross-map-based techniques, we develop a general framework to advance towards a comprehensive understanding of dynamical causal mechanisms, which is consistent with the natural interpretation of causality. In particular, instead of measuring the smoothness of the cross-map as conventionally implemented, we define causation through measuring the scaling law for the continuity of the investigated dynamical system directly. The uncovered scaling law enables accurate, reliable, and efficient detection of causation and assessment of its strength in general complex dynamical systems, outperforming those existing representative methods. The continuity scaling-based framework is rigorously established and demonstrated using datasets from model complex systems and the real world.

BACKGROUND Chemical phase analysis of antimony ores involves three mineral phases:valentinite, stibnite and insoluble antimonate. Solvents used for extracting various antimony mineral phases are different. In addition, coexisting ions are complex and concentration gradients vary greatly. These factors affect the accurate determination of antimony chemical phases by inductively coupled plasma-optical emission spectrometry (ICP-OES). OBJECTIVES To solve the problem during rapid and accurate measurement of chemical phases of antimony ore. METHODS The effects of hydrochloric acid, nitric acid and potassium sulfate-nitric acid-sulfuric acid on the determination of antimony by ICP-OES were studied with valentinite, stibnite and antimonate as selective separation solvents. RESULTS The same concentration of hydrochloric acid and nitric acid medium had no effect on the determination of antimony. The same standard solution series can be used to determine antimony in valentinite and stibnite. Hydrolysis of antimony can be avoided by using 15%-20% hydrochloric acid or nitric acid of. Mixed acid medium (4g/L potassium sulfate-15% nitric acid-3% sulfuric acid) had an effect on the determination of antimony. The matrix matching method can be used to solve the problem. In determining the amount of antimony in antimonate, the calibrated solution was formulated to add the same amount of mixed acid as the antimonate leaching agent. The detection limits of antimony in valentinite, stibnite and antimonate mineral phases by ICP-OES were 0.0006%, 0.0012% and 0.0021%, respectively, by choosing the 206.833nm line as the analytical line, under optimized analytical method flow and measurement parameters. The relative standard deviations (n=12) of the method were 0.16%-5.76%, and the absolute relative deviations of phase addition and total amount were 0.07%-7.38%. CONCLUSIONS The precision and accuracy of the method meet the quality control requirements of antimony ore chemical phase analysis, and provide fast and accurate measurement of antimony ore chemical phase.

This paper presents a finite-element approach to simulate the buckling process of the composite laminated plate containing a buried delamination. The delaminated composite laminates are analyzed using solid elements. In order to prevent the mutual penetration between the two parts above and below the delamination and to ensure coordinated deformation, a normal behavior of hard contact is applied at the interfaces of the delamination to take into consideration of the nonlinear contact effect between the debonded regions. Parametric analyses are conducted to investigate the effects of delamination depth, delamination length and aspect ratio on the buckling loads. Furthermore, buckling of a perfect laminate with the same geometrical parameters is simulated to obtain the critical buckling load. A comparison between the finite element prediction and the classic theoretical solution for the perfect laminate is carried out. It is found that they are in good agreement. The established model can simulate the buckling process of the composite laminated plate accurately.

[Objectives] The interaction between the body of pod propulsor and the propeller is great, leading to complex flow phenomena. As a consequence,under steering condition which is away from design point,loads of blades change sharply and the cavity characteristics deteriorate. In order to analyze the hydrodynamic characteristics of the pod propulsor,[Methods] the full structural grid based on the Reynolds Averaged Navier-Stokes (RANS) approach is adopted. Besides,the cavity structures are predicted by the Sauer model. Finally,the model experiment of the pod propeller is carried out in the cavity channel.[Results] The results show that the numerical data are in great agreement with the experiment counterparts which presents the correspondingly high accuracy of this numerical model. Under steering condition,the thrust and torque of pod propulsor are greater than the counterparts under straight condition. After the propulsor deflects,the pressure at different circumferential positions fluctuates with the change of circumferential angle. What's more,cavity contours show different structures and the cavitation intensifies as the deflection angle rises.[Conclusions] The research results can provide reference for the design of pod propeller.

Purposes: Since the role of store-operated calcium entry (SOCE) in endothelium-dependent hyperpolarization (EDH)-mediated vasorelaxation of mesenteric arteries in health and colitis is not fully understood, cyclopiazonic acid (CPA), a specific inhibitor of the sarco(endo) plasmic reticulum calcium-ATPases (SERCA), was used as a SOCE activator to investigate its role in normal mice and its alteration in colitis mice.Methods: The changes in Ca2+ signaling in vascular endothelial cells (VEC) were examined by single cell Ca2+ imaging and tension of mesenteric arteries in response to CPA were examined using Danish DMT520A microvascular measuring system.Results: CPA activated the SOCE through depletion of the endoplasmic reticulum (ER) Ca2+ in endothelial cells. CPA had a concentration-dependent vasorelaxing effect in endothelium-intact mesenteric arteries, which was lost after endothelial removal. Both nitric oxide (NO) and prostacyclin (PGI2) inhibitors did not affect CPA-induced vasorelaxation; however, after both NO and PGI2 were inhibited, KCa channel blocker [10 mM tetraethylammonium chloride (TEA)] inhibited CPA-induced vasorelaxation while KCa channel activator (0.3 μM SKA-31) promoted it. Two SOCE blockers [30 μM SKF96365 and 100 μM flufenamic acid (FFA)], and an Orai channel blocker (30 μM GSK-7975A) inhibited this vasorelaxation. The inhibition of both Na+/K+-ATPase (NKA) and Na+/Ca2+-exchange (NCX) also inhibited CPA-induced vasorelaxation. Finally, the CPA involved in EDH-induced vasorelaxation by the depletion of ER Ca2+ of mesenteric arteries was impaired in colitis mice.Conclusion: Depletion of ER Ca2+ by CPA induces a vasorelaxation of mesenteric arteries that is mediated through EDH mechanism and invokes the activation of SOCE. The CPA-induced endothelium-dependent dilation is impaired in colitis which may limit blood perfusion to the intestinal mucosa.

C36H40N6O4, monoclinic, P21/c (no. 14), a = 11.094(6) Å, b = 17.694(11) Å, c = 8.698(5) Å, β = 103.56(2)°, V = 1659.9(16) Å3, Z = 2, Rgt(F) = 0.0470, wRref(F2) = 0.1375, T = 273 K.

The effect of different process parameters on solidification of industrial gas turbine hollow blades via HRS (High Rate Solidification) and LMC (Liquid Metal Cooling) was studied by ProCAST software. The results show that the paste zone via LMC process is much narrower than that by HRS process and the shape of the S/L (solid/liquid) interface is more flat. The axial thermal gradient of the blade by LMC process is about three times higher than that by HRS process. The cooling rate of the blade is 0.3-2.00℃/s by LMC process, which is far higher than that by HRS process (0.05-0.16℃/s). In LMC process, low holding temperature can still ensure high temperature gradient and cooling rate of the blade; while in order to avoid blocking of stray grains to the initial grains at the platform of the blade, HRS process should adopt high holding temperature and lower withdrawal rate. The calculated and the measured results show that compared with the blade prepared by HRS process, the PDAS (primary dendrite arm spacing) is much finer in the blade prepared by LMC process.

Objective To evaluate the prognostic value of CEA, CA125, CA199, NSE, CYFRA21-1 and SCC-Ag as serum tumor markers on the diagnosis of operable non-small cell lung cancer(NSCLC) after radical operation. Methods We reviewed 1851 consecutive NSCLC patients who underwent radical resection from January 2005 to December 2014. We used analysis of variance (ANOVA) to analyze the associations between tumor markers and pathological stage. Survival probability was estimated by the Kaplan-Meier method. Cox proportional hazards regression was used to identify independent prognostic factors. Results The positive rates of CEA, CA125, CA199, CYFRA21-1 and SCC-Ag in stage Ⅱ and Ⅲ NSCLC were higher than those in stageⅠ(P < 0.001), but there was not significant difference among different stages for NSE (P=0.743). The overall survival in negative group of CEA, CA125, CA199 and CYFRA21-1 were better than those in positive group respectively (P < 0.05), but the survival in positive group of NSE was better than that in negative group (P=0.033). SCC-Ag negative group had longer survival time than SCC-Ag positive group, without statistically significant difference (P=0.072). CEA (HR=1.572, 95%CI: 1.117-2.214, P=0.010), CA125(HR=2.464, 95%CI: 1.610-3.772, P < 0.001), CYFRA21-1 (HR=1.445, 95%CI: 1.044-2.000, P=0.027) were detected to be independent risk factors for the prognosis of NSCLC patients. Conclusion CEA, CA125 and CYFRA21-1 play an important role prior to CA199, NSE and SCC-Ag in predicting severity and prognosis of NSCLC patients.

[Objectives] In order to study the applicability of different turbulence models in propeller flow noise prediction, taking the DTMB 4119 propeller as the research object, the numerical simulation method is used to calculate the frequency domain noise under the non-uniform flow field.[Methods] First, the hydrodynamic coefficient and surface pressure distribution coefficient are obtained via the RANS method and the accuracy of the flow field simulation is verified by comparing it with the experimental data. Next,the pulsating pressures obtained by RANS, DES and LES are considered as the sound source respectively, and combined with the acoustic boundary element method to predict the radiation noise.[Results] The results show that spectral noise is the main contributor to total noise; when noise on 1 BPF is predicted, the results obtained by the three methods are very similar, so we can use RANS to predict noise quickly; when noise on the high order of BPF needs to be predicted, the calculation results of LES are better.[Conclusions] In noise prediction, the appropriate turbulence simulation method can be selected according to the demand.

Currently, a few chemical phase analysis methods possess a common application, but most of them are designed for samples in a specific ore district and thus the accuracy of analytical results and the application range of a selected analytical process are not certain. Verification of chemical phase analysis by selected analytical process and method accuracy are the primary problem in this field. The representative antimony ore type, single antimony sulfide ore was chosen as the research object for the study. The main mineral phases of antimony are determined by mineral identification. When valentinite mineral cannot be acquired, the proportion of valentinite in mixing oxide ore (mixture of valentinite and antimonate) is determined by valence analysis. Moreover, the selected separation condition among valentinite, stibnite and antimonate is determined by comparison of condition experiment and X-ray Diffraction Analysis. Results show for the sample with antimony suldide content higher than 35%, the extraction time for the antimony sulfide phase should change from 30 minutes to 40 minutes. When the leaching rate of stibnite is increased by 4%-6%, the analysis error of antimonates phase can be reduced by 45%-70%. Antimony sulfide was leached completely, and the analysis accuracy of antimonite and cervantite phases improved. This method is suitable for chemical phase analysis of different types of ores (oxidized and sulfide ores) from different regions.

For now, many hospitals that require nurses to move patients by hand from stretchers to a hospital bed, so a design of stretcher with auxiliary functions of lateral positioning and transferring for immobilized patients, which is a mechanical mechanism consisted of rigid rods, joints and sliders, was designed to help the nurses to move patients between beds and reduce their workload. Driven by motors, the rigid rods can be rotated, stretched or shortened so that the entire stretcher bed board can archive to a proper posture and position. In this paper, the following objectives will be achieved: (i) Create a schematic of the mechanism and describe the principles and functions (ii) the calculation of inverse kinematics, forward kinematics, dynamics (including energy), and PD control in the mechanism (iii) The motion process of simulating the mechanism using MATLAB (iv) Using MATLAB to create the plots of angle, torque, and position state (v) Using SolidWorks to construct the prototype and to implement the motion simulation of the mechanism (vi) Describe the practical application and future Extensions of this mechanism.

Anion exchange resin has been applied to Re separation after acid digestion of Cu-Pb-Zn ores and Re was determined by Inductively Coupled Plasma-Mass Spectrometry(ICP-MS). ReO4- in solution was adsorbed by exchange resin and was then eluted from the resin by eluant. This method has a long process, which affects its stability and accuracy. Matrix elements are selected as the goal and 8 g of 732 cation exchange resin in 2% nitric acid medium for 1.5 h static adsorption is used. This method can effectively eliminate the influence of matrix elements on the ICP-MS determination of rhenium. Quartz was used as the blank and mixed with low Re samples. The acquired detection limit was 0.004μg/g, the precision(RSD) is less than 6%, and the recovery ranged from 96% to 104%. The 732 cation exchange resin under the acidic condition has the recovery of >95% for most matrix elements except tungsten and molybdenum, which reduced ionic strength and the concentration of interference elements. Rhenium can be directly determined by ICP-MS, which is simpler and faster than the anion exchange resin separation method.

Hydride Generation (HG) combined with Inductively Coupled Plasma-Optical Emission Spectrometry (ICP-OES) has excellent analytical sensitivity. However, the instable chemical reactions of HG may cause unsatisfactory analytical precision. In this study, a novel and self-made HG system coupled with ICP-OES was developed for measurement of As, Sb and Bi in geological samples. Inner diameter (i.d.) of introduction tubing changed from 0.32 mm to 0.76 mm. Reaction tubing i.d. changed from 0.76 mm to 1.14 mm and length increased from 30 cm to 50 cm. These changes significantly improve the stability of HG reaction by increasing space and time of chemical reactions to reach reaction equilibrium. Arsenic, Sb and Bi were firstly leached from soil and stream sediment using HCl-HNO3 water bath, pre-reduced by thiocarbamide-ascorbic acid mixture, and were finally determined by the modified HG-ICP-OES. The detection limits of this method are 0.35 μg/g, 0.33 μg/g and 0.25 μg/g for As, Sb and Bi, respectively. The linear ranges are 1.1-300 μg/g for As, 1.0-100 μg/g for Sb and 0.75-100 μg/g for Bi, which is sufficient for the measurement of As, Sb and Bi in geological samples.

The basic definition and the characteristics of three service principals of reverse supply chain service for the iron and steel industry is analyzed according to the reverse supply chain process of the iron and steel industry. Based on this work, a two-hierarchical and three-dimensional reverse supply chain service process model is built for the iron and steel industry. A three-dimensional service space is constructed, including services abstraction, service organization and collaborative operation, and service network control and service value-added. In the space, the first hierarchical service response constituted by the three stages of service programme matching and decision-making, and the second hierarchical service response constituted by the two stages of service function realization are accomplished. The key technology of service process realization including service modularization, service knowledge acquisition and sharing, and service modular intelligent matching is discussed. Finally, the feasibility of the model is proved by a case of scrap steel reverse supply service for one iron and steel enterprise.

For coarse gold-containing ore, the existence of the coarse grained gold makes it challenging to collect, process and analyze ore samples, so the issue of how to obtain representative samples with great uniformity for chemical analysis, and provide accurate analysis results, has been a pressing technical difficulty in the gold mine resource exploration and evaluation. The progress and achievements of the coarse gold-containing ore sample collection, processing and analysis method of recent years at home and abroad are summarized in this paper and discussed as follows: (1) coarse gold-containing sample collection is to ensure that the primary part of representative samples, including the potential error of the result of a coarse grained gold samples 80% comes from samples collected, so the economic and effective sample collection method is very important. (2) Coarse gold-containing sample processing mainly includes the increase of natural gold crushing degree, improving the machining process for the first time, selecting the sample processing equipment, and so on but determining the size distribution of gold and associated minerals is the key to sample processing. (3) Coarse gold-containing sample analysis involves a conventional chemical analysis method, bulk-leachable extractable gold (BLEG) analysis and the artificial sand weight weighted average method. Compared with the complex processing process study, the latter is expected to become such an economic and effective analysis method. The quality of coarse gold mine resource evaluation error comes from many aspects, such as geological, sampling, processing and analysis. To minimize error at all stages, and to pay particular attention to the study of sample collection method, and to ensure the representative samples collected, and all of the above are the premise of improving this kind of gold ore resource assessment quality.