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In this paper, the contents of 12 mineral elements in 100 samples of four types of takeaway fast food, including porridge and noodles, special snacks, Chinese fast food and Western fast food, sold in Beijing were analyzed by ICP-MS, and the RNI and UL values of the elements were used as the assessment criteria for preliminary dietary nutritional assessment of different age groups. The results showed that the range of mineral element contents in the samples was wide and the degree of dispersion was large. The intakes of Na, I and Cr could meet the daily dietary needs of the whole population in all types of takeaway samples, while the intakes of Ca, Mg and Fe were insufficient. The insufficient intakes of K, Zn, Cu, Mn, Mo and Se were found in some of the samples of some populations. The intakes of the 12 elements showed different degrees of variability among the four types of takeaways, with lower intakes of each element in congee and noodle dishes, and K, Ca, Mg, Zn, Fe, Se and Cr showed significant differences from the other three types. The intake of each element was lower in congee and noodles, which showed significant differences with the other three categories. In addition, the intake of take-away fast food was found to be excessive, with Zn and I exceeding 1.1%~5.3% and 3.6%~14.3%, respectively, in different age groups. The results showed that the long-term take-away population should pay attention to adjusting their dietary structure, balancing the intake of take-away food containing meat, vegetables, legumes, eggs and milk, and appropriately replenishing various types of minerals with insufficient intake. At the same time the health risks of “over-nutrition” brought about by fast food takeaways should be paid attention, and the young minors were the key concern groups.

In order to explore quality evaluation methods for Chinese coffee beans for freshly ground coffee and instant coffee and to select evaluation indicators, the major quality indicators were selected from the basic quality indicators through the Delphi evaluation method and sequence relationship analysis to construct a quality index system. Then the differences in the major quality indicators of 53 coffee bean samples from different production areas in Yunnan and Hainan provinces were determined, the characteristic quality indicators of coffee beans for different purposes were selected by correlation analysis, principal component analysis (PCA) and cluster analysis, and stepwise multiple linear regression analysis was conducted based on the comprehensive scores of the principal components of the samples. Finally, grain size, taste, aroma and carbohydrate content were selected as the characteristic quality indicators of instant coffee and grain size, taste, aroma and caffeine content as the characteristic quality indicators of freshly ground coffee. It is determined that the major varieties suitable for instant coffee are Catimor and Typica, and the major production area is Yunnan province. The major variety suitable for freshly ground coffee is Catimor, and the major production area is Yunnan province.

Abstract The formation and emission of sulfur trioxide (SO3) in sulfur recovery unit has received increasing attention due to its adverse effects on the operation of plant and environment. Due to the excess oxygen, high concentration of SO2 and high temperature, SO3 formation in the sulfur recovery unit tail gas incinerator may significantly increase. A small horizontal tube reactor was employed to simulate the homogeneous oxidation of SO2 in the tail gas incinerator. The SO3 concentration was measured with a controlled condensation method at the outlet of the reactor. The present work focuses on the gas-phase chemistry and examines the impact of different combustion parameters and atmospheres on the formation of SO3 in the tail gas incinerator. Experiment results show that the increased O2 and SO2 concentrations along with increasing temperature are favorable for enhancing SO3 formation over the range of tested parameters. The presence of water vapor has an enhancing effect of SO2 oxidation in the experiments conducted. No significant effect of CO2 was found to the oxidation of SO2.

In the context of rapid technological development, the digital transformation of non-heritage culture is significant, which not only helps to protect and inherit, but also attracts more audiences through innovative ways. This study explores non-heritage cultures’ virtual experience interaction design and promotion methods. It investigates the optimization of digital revitalization and interaction design of non-heritage handicrafts with deep learning oversampling techniques to enhance user experience and promote cultural dissemination. After effective screening, 400 valid samples were obtained after collecting 450 questionnaires during the experiment. The interaction design of non-heritage virtual experiences optimized with deep learning technology can significantly improve users’ knowledge and interest in non-heritage culture. The correct rate of participants’ cognition of NRL cultural content increased to more than 95% on average after the experience, in which the proper rate of cognition of plant elements and arrangement forms was as high as 98.9%. The study found that the community interaction function plays a significant role in improving user satisfaction. Deep learning oversampling technology has a substantial effect on the virtual interaction design of non-heritage culture, which can effectively promote the living inheritance and promotion of non-heritage culture.

The article takes the application of digital media technology in the spatial layout design of art exhibition halls as the entry point, and utilizes Web technology and the integrated simulation platform of urban VRGIS to establish the virtual space of immersive art exhibition halls. The article obtains binocular imaging data through binocular visual imaging model and solves the three-dimensional coordinate system by using the method of polar geometric constraints, and then reconstructs the three-dimensional space through the point cloud data to realize the design of the virtual space of the immersive art exhibition hall. The article evaluates the effectiveness of the immersive art gallery virtual space from three aspects: interactivity, DPI recovery value and eye movement data visualization. It is found that users are most effective with direct interaction within an interaction depth of 1.1 m to 1.7 m. In comparison, ray interaction is more appropriate when the interaction depth exceeds 2.3 m. Applying the method of this paper, the global DPI recovery value of the immersive art gallery can reach 89.67%, and the pupil diameter of the subjects can reach about 5.79 mm in the virtual space test over 160 seconds. In this paper, digital media technology can more effectively realize the immersive presentation of art theories, to better satisfy people’s growing spiritual needs and provide more diverse cultural experiences.

In order to further reduce the errors arising in synchronous sampling, this paper designs a multi-channel hybrid sampling electrical parametric feature modeling method based on an AIOT sensing module in the process of design. The AIOT sensing module is used to process the received RF signals using a transconductance amplifier to improve the digitization and reconfigurability of the RF front-end circuit. The signal is transformed and calculated using the Fast Fourier Transform to obtain electrical parameters such as the amplitude of each harmonic and the power factor. The results show that the variation amplitude of the window function of the design method in this paper is generally maintained between -1.5 and 1.5, the amplitude accuracy of the active power rate is within 3.17555%, and the relative error accuracy is within 0.000951%. It can be seen that the AIOT-based sensing module can significantly improve the calculation accuracy of electrical parameters and can be applied to the process of sampling digital measurements of other power signal characteristics.

This paper performs data fusion based on a multi-sensor fusion algorithm, which measures the sensors and calculates the distance between the data to obtain the measurement weights when participating in the fusion. The sensor observation model is created using an extended Kalman filter, and the nonlinear state transition function is linearized using the covariance matrix. Accurately estimating sensor inter-cluster data is necessary to achieve the scalability of online detection technology for charging piles. The results show that the disconnection time of the contactor of the charging pile transfer type equipment is 1.153s after the simulated charging pile output over-voltage in the disconnection time detection. The online detection efficiency can be improved by using multiple sensors, the method analysis can be intuitive, and the charging service capability of the electric vehicle charging pile can be effectively improved.

Prepared aquatic products have recently shown a momentum of rapid development due to its convenience and easy availability. With the characteristics of high protein content, high water content, and neutral pH, prepared aquatic products are susceptible to oxidation, microorganisms, and endogenous enzymes, leading to flavor deterioration. With the continuous development of the prepared aquatic products industry, understanding the mechanism of flavor deterioration in prepared aquatic products is of great significance for their quality maintenance and flavor regulation. In this context, the mechanism of flavor deterioration in prepared aquatic products is reviewed herein from the perspectives of protein oxidation, lipid oxidation, microorganisms, and endogenous enzymes. Furthermore, the methods for the flavor regulation of prepared aquatic products through processing techniques, exogenous additives, and packaging methods are discussed. We expect that this review will provide a reference for the flavor maintenance of prepared aquatic products and the development of the prepared food industry.

In this study, the effects of different freezing methods namely air freezing, cryogenic freezing, freezing after dipping in a refrigerating medium consisting of 20% ethanol (V/V), 20% propylene glycol (V/V), 5 g/100 mL trehalose aqueous solution and freezing after dipping in anhydrous ethanol on the quality of sea bass were investigated. The results showed that the freezing rates of refrigerating medium freezing and anhydrous ethanol freezing were 8.20 and 6.25 cm/h, which were 32.80 and 25.00 times as high as that of air freezing, respectively. The microstructure of frozen sea bass showed that the small ice crystals formed between muscle tissues were small, and the muscle fibers were closely arranged. Refrigerating medium freezing was more conducive to maintaining the water-holding capacity (WHC) of muscle tissues and slowing down the migration of immobilized water, and had a significant effect on maintaining the freshness, texture properties and protein thermostability of fish fillets. In summary, refrigerating medium freezing can effectively slow down the quality deterioration of frozen sea bass. The results of this study will provide a theoretical and practical basis for improving the storage quality of frozen aquatic products.

Accuracy of airborne radar antenna servo control(ARASC)is one of important index for radar system to accurately search,identify and detect targets.Radar antenna bears greater air resistance during scanning motion,because of the wind speed and moving speed of the carrier.As the atmosphere resistance is changed along with time and different scan movement angle,it will bring additional load disturbance torque for ARASC.In order to control the influence of disturbance on accuracy of ARASC,which based on disturbance observer(DOB),a solving scheme is put forward in this paper.ARASC dynamic model and servo control model are established,additional load torque generated by atmosphere resistance is import to input of controlled object for putting up compensate to improving accuracy in practical environment.Modeling simulation and experimentation analysis are put up with different wind speed influence,simulation experimentation show accuracy of ARASC based on disturbance observer is improved obviously.

Industrial waste salt is mainly produced by industrial production processes of pesticides, drug synthesis, printing and dyeing, as well as solid-liquid separations, concentration and crystallization of solution, and sewage treatment, etc. At the present stage, the annual output of waste salt in China has exceeded 2.0×107 tons and the high-temperature melting method is considered to be a promising treatment method, but there are problems such as molten salt adhesion and agglomeration, unused high-temperature sensible heat, and waste of water resources. A novel process for waste heat recovery by high temperature melting dry method is proposed in this paper, using a combination of centrifugal granulation and waste heat recovery to dispose high-temperature molten salt and effectively recover heat. Through thermal equilibrium analysis and calculation, the waste heat recovering efficiency of the waste heat recovery using the novel process can reach up to 98%. Taking the annual treatment of 100,000 tons of waste salt as an example, the benefits of effective heat recovery converted to standard coal could be approximately 5 billion. While efficiently utilizing waste heat resources, the novel process brings considerable economic benefits to enterprises, has good industrial application prospects, and helps to advance the process of national hazardous waste solid waste treatment.

Due to the high threshold requirements of applying for a large number of loans from banks, more and more small and medium-sized enterprises have chosen private placement to raise funds, and the betting agreements have been signed to protect the interests of both enterprises and investors. This paper analyzes the case that the bet agreement was applied by Mengniu Dairy and Morgan Stanley in private equity financing. It firstly expounds its background and financing process at that time, then explores why Mengniu Dairy can bet successfully. Finally, countermeasures and suggestions are put forward to promote success of the gambling agreement in private equity especially for small and medium-sized enterprises.

The cylindrical samples of TC4 titanium alloy prepared by spark plasma sintering (SPS) were compressed with hot deformation of 70% on the thermosimulation machine of Gleeble-1500. The temperature of the processes ranged from 850°C to 1,050°C, and the strain rates varied between 0.001 and 5 s−1. The relative density of the sintered and compressed samples was measured by the Archimedes principle. During hot deformation, the microstructure of the sample was observed. The results show that the average relative density of the samples was 90.2% after SPS. And the relative density was about 98% after the hot deformation of 70%. Under high temperature (>950°C), the sensitivity of flow stress to temperature was reduced. At low strain rate (0.001 s−1), the increase in the deformation temperature promoted the growth of dynamic recrystallization (DRX). At the same temperature, the increase in strain rate slowed down the growth of DRX grains. And the variation tendency was shown from the basket-weave structure to the Widmanstätten structure at a low strain rate (

The TC4 titanium alloy powder test piece was prepared by spark plasma sintering. The multi-pass hot deformation of the TC4 titanium alloy was tested by using the Gleeble-1500 experiment machine. Measurement of relative density, X-ray diffraction, optical microscopy, scanning electron microscopy and electron backscatter diffraction were carried out for the TC4 titanium alloy. In order to reveal the evolution of the microstructure, describing its changes systematically is necessary, which has become the focus of this article. The results show that after multi-pass hot deformation, the relative density of the TC4 titanium alloy could reach 99.93%. With the increase in deformation and decrease in temperature, the β-transformed phase was retained, and many fine β-transformed phases were formed between two adjacent lamellar α. During the one-pass hot deformation, the rapid increase in relative density was the main reason for the instability of the flow stress in the stress–strain curve. For two-pass and three-pass hot deformations, more features of dynamic recrystallization and the characteristics of dynamic recovery at high strain rates (5 s−1) could be found. The size of the grains was about 15 µm after the three-pass hot deformation.

Abstract Cu and Fe are the main impurity elements in the hydrometallurgical regeneration of spent lithium‐ion batteries. Hence, it is important to study the effect of Cu and Fe doping on the structures and electrochemical properties of cathode materials. In this study, a series of Cu‐ and/or Fe‐doped LiNi0.8Co0.15Al0.05O2 cathode materials are synthesized by spray pyrolysis and high‐temperature solid‐state method. The inductively coupled plasma (ICP), X‐ray diffraction (XRD), and Rietveld refinement results reveal that Cu and Fe can incorporate into the crystal lattice and cation mixing is suppressed. The X‐ray photoelectron spectroscope (XPS) results show that the relative ratio of Ni2+/Ni3+ on the surface is effectively decreased. Electrochemical results display that the electrochemical performances of Cu‐ and/or Fe‐doped samples are improved when the atomic ratio of Ni to Cu and Ni to Fe is greater than 79.0 and 399.0, respectively. The dQ/dV, GITT, EIS, XRD, and XPS studies indicate that the structure stability, Li+ diffusion coefficient, and charge transfer can be increased by appropriate Cu and/or Fe substitution. The results suggest that appropriate Cu and Fe can be doped into LiNi0.8Co0.15Al0.05O2 as beneficial elements rather than removed as impurities.

The article analyzes the role of driving m-commerce with social networking and therefore provides insight into how the application of mobile apps influences customers’ perceptions on purchasing products online and on the mode of payment. The consumers are engaged in social interactions through the internet by the new opportunities provided by social media. These interactions provide and generate certain values for both businesses and consumers. An upsurge in the application of social media on mobile phones by users is evident, giving optimism and the ability to view the role of the integration of m-commerce into social media. Certain criteria like mobile app compatibility, trust, perceived value of mobile phone apps for online shopping, and online payment are examined from the point of view of consumers who purchase products, save purchase time, and provide easy use and security through social networking sites and m-commerce. Adoption of a digital mode of payment is affected by the education level of the consumers as, if they are internet savvy, they will be more inclined to use the digital payment mode. The article not only discusses the role of education in the better understanding of consumers toward the application of online modes of transaction through mobile phones, but also indicates that there are security issues, although these have been resolved to some extent by technological advances. Yet, there is need for the retailers as well as the consumers to achieve further technological progress.

Commercially pure(CP) Ti fabricated by 135° ECAP and swaging was annealed at 100, 150, 200, 250, 300, 350, 400, 450℃ and 500℃ for 1h, respectively. The microstructure and properties of annealed commercially pure Ti were investigated by transmission electron microscopy, scanning electron microscopy, uniaxial tensile test and microhardness test. The results show that when annealing temperature is below 400℃, dislocation density reduces gradually and grain boundary becomes clear, no obvious change occurs in the microstructure,ultimate tensile strength and microhardness decrease slightly and no obvious increase occurs in the elongation;when annealing temperature is above 400℃, recrystallization occurs with the increase of annealing temperature, and the grain size increases obviously, the average size is about 5μm, the ultimate tensile strength and microhardness decrease significantly and elongation increases at the same time. The tensile fracture shows the tensile fracture of annealed commercial pure Ti by ECAP and swaging is ductile fracture. With the increase of annealing temperature, the size and depth of dimples increase.

The effect of mischmetal of lanthanum and cerium on the composition and structure of the corrosion products on the surface of AZ91 Mg alloy in deicing salt solution under dry-wet cycles was investigated by scanning electron microscopy (SEM), X-ray diffraction (XRD) and energy dispersive spectrometer (EDS). The results show that the corrosion products of AZ91 Mg alloy without mischmetal addition (La,Ce) are mainly composed of Mg(OH)2, MgO, CaCO3 and Mg6Al2CO3(OH)16·4H2O; and (La,Ce)AlO3 can be found in the products of AZ91 with mischmetal addition, meanwhile dense layer occurs in the corrosion products. Electrochemical impedance spectroscopy (EIS) measurements show that the charge transfer resistance of AZ91 alloy with mischmetal addition tested in the same dry-wet cycles is much higher than that of AZ91 alloy, the addition of mischmetal helps to reduce the dispersing effect of impedance spectroscopy, indicating that the corrosion resistance of AZ91 Mg alloy and the stability of corrosion product films can be improved by mischmetal of La and Ce.

which the singular element appears in the optimum process and the result may be a partial optimum solution are two disadvantages when using the ESO method to optimize 2- D model. In this paper,two algorithms are proposed for solving these disadvantages. One is filter and rejection algorithm based on the trait of singular element. Using this algorithm,only one parameter is needed to control filtering and deleting,and the parameter is determined by the number of elements linked around singular element. The other is interval approximation algorithm. Minimum initial rejection rate R0minwhich fulfill removed conditions was ascertained by using this algorithm and it was used as starting value,thus other initial rejection rate R0 were obtained by setting certain increment. Two algorithms mentioned above were implanted in the existing ESO method,then optimizing respectively with different initial rejection rate which were obtained before and the available structures from the results was filtered out in terms of performance parameters. The results of optimization for numerical 2-D structures indicate that the improved ESO method has better suitability and stability than the existing one,and it avoids shortcoming that the result may be a partial optimum solution when using the existing ESO method.

This study proposes regulatory, normative, and cognitive dimensions and empirically investigates how these three dimensions take form in a measure of institutional environment from gender perspective. The study carried out the work within the micro-ebusiness sector in China and collected the data with 689 females and 357 males. Exploratory factor analysis (EFA) is used to test the dimensionality of institutional environment. It also used Cronbach’s alpha to check the reliability of the intended measure. The findings show that the early scholars’ measurement of the institutional environment in regulatory, normative, and cognitive dimensions still applies to Chinese males in the micro-ebusiness sector. However, the specific items regarding regulatory and normative form distinct factors of what mixed the two dimensions in female group. From the evidence of China, it challenges the widely recognized measurement of institutional environment, which need to be redesigned for females in regulatory and normative dimensions. The study outcomes provide a better understanding of how different the institutional environment was evaluated and functioned to female and male. It can help government departments reconsider and improve institutional environment to promote entrepreneurship from gender perspective. This new perspective would add some insights into the literature of micro-ebusiness and enhance the knowledge of the dimensionality of institutional environment.

Atmospheric deposition is an important source of heavy metals in surface soil, the study on the geochemical characteristics and source analysis of heavy metals in atmospheric dust would provide important guidance for pollution prevention. The contents of heavy metals (As, Cd, Cr, Cu, Hg, Ni, Pb, Zn) in atmospheric dust in Jinan have been analyzed by Atomic Fluorescence Spectrometry (AFS), Inductively Coupled Plasma-Mass Spectrometry (ICP-MS), and X-ray Fluorescence Spectrometry (XRF). The correction analysis and principal components analysis (PCA) were used to source the heavy metals. The average contents of Cd, Cr, Cu, Hg, Pb and Zn in atmospheric dry and wet deposition are 2.07 mg/kg, 135.9 mg/kg, 65.7 mg/kg, 218.6 μg/kg, 110.7 mg/kg, 380 mg/kg, respectively, which are higher than the background values of these elements in soil and has an obvious enrichment due to the contamination by human activities. Cd, Cu, Hg, Pb are mainly derived from coal combustion, As and Cr are derived from road dust, Ni may be derived from soil dust, and Zn is derived from traffic discharges. The coal combustion and road dust are the main pollution sources of atmospheric deposition in Jinan, with the contribution proportion of atmospheric deposition up to 50.13%. Atmospheric dry and wet deposition produce significant effect on the contents of Cd, Hg, Cr, Pb, Zn and As in urban topsoil, the annual deposition flux of Zn is the highest with a mean of 148 mg/(m2·a), whereas the annual deposition flux of Hg is the lowest with a mean of 0.085 mg/(m2·a). Moreover, Cd and Hg contents have higher growth rates, and dry and wet atmospheric deposition significantly influences the As and Cr accumulation in soils.

Bound-constrained Support Vector Machine(SVM) is one of the stateof- art model for binary classification. The decomposition method is currently one of the major methods for training SVMs, especially when the nonlinear kernel is used. In this paper, we proposed two new decomposition algorithms for training bound-constrained SVMs. Projected gradient algorithm and interior point method are combined together to solve the quadratic subproblem effciently. The main difference between the two algorithms is the way of choosing working set. The first one only uses first order derivative information of the model for simplicity. The second one incorporate part of second order information into the process of working set selection, besides the gradient. Both algorithms are proved to be global convergent in theory. New algorithms is compared with the famous package BSVM. Numerical experiments on several public data sets validate the effciency of the proposed methods.

The Jiangxi Lengshuikeng ore field, characterized as porphyry deposits and volcanic sedimentary hydrothermal reworking deposits, is one of the major Ag-Pb-Zn ore concentration areas in Wuyi Mountain area. There has been much research carried out on mineralization, the metallogenic model, and ore-controlling structure of the Lengshuikeng deposit. However, it is still unclear about the relationship of different geological bodies with mineralization and magmatism. In this paper, a description of a zircon LA-ICP-MS U-Pb geochronology approach and its implementation on the volcanic rock of Daguding Formation and ore-bearing granite porphyry is given. The crystal tuffs from the top and bottom of Daguding Formation and ore bearing granite porphyry yield U-Pb age of 161.3±1.3 Ma, 160.75±0.96 Ma and 168.09±0.80 Ma, respectively. These results indicate that there were three stages of volcano-magmatic activities in the Lengshuikeng ore field with ages of 164-170 Ma, 157-161 Ma, and 140-146 Ma, respectively. The 157-161 Ma is the main metallogenic epoch of the volcanic sedimentary-hydrothermal reworking type deposit and porphyry type deposit. The discovery of the late Jurassic volcanic rocks in Lengshuikeng provides the important geological evidence for the detailed study of the Mesozoic tectonic regime transition in South China.

Although there is poor outcrop in the area, the Daoxiang formation exposed in North Fujian has unique rock assemblage and metamorphism, and deformation characteristics show that the Daoxiang group does exist, and belongs to metamorphic rock of the Cambrian period in previous research with Sm-Nd model age as (500±35) Ma. However, the limitations of the test method, adversly influence the the reliability of the formation age. LA-ICP-MS U-Pb dating provides reliable and precise evidence of the formation age of the rocks. Zircon LA-ICP-MS U-Pb data of basalt and siliceous rocks carried out by this group show that the newest age of basalt is (111.4±2.0) Ma, i.e. belonging to Early Cretaceous, which represents the lower limit of the formation age. The result is consistent with that of siliceous rocks, the newest of which is 124 Ma. The inherited zircon ages indicate proterozoic-paleozoic-mesozoic materials may be included in the source region, so the Daoxiang formation should be further disintegrated, the Vesicular basalt and Siliceous rocks which formed at Mesozoic should be separated from the Daoxiang formation. The discovery of all these ages enriches research work of tectonic evolution of Daoxiang formation and provides valuable data of the isotopic geochronological age.