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China's Danxia landforms are characterized by their indicative red color. Portable ground object spectrometers are widely used owing to their small size, ease of operation in the field, rapid measurements, and simple operation. In this study, we analyzed the characteristic parameters of the reflection spectra of the Danxia rock wall surfaces (i.e., red surfaces, orange surfaces, and pure white spots) and different types of plant cover, as well as their quantitative relationships with color tones, using the visible-near-infrared (VNIR) reflectance spectra of the rock walls. The results indicate that the absorption depths and areas of the red and orange surface samples were highly correlated at 525 and 500 nm, as were the redness and orangeness of the samples. The redness and orangeness of the indoor and outdoor samples were relatively consistent with the absorption depth and area growth rates; however, the indoor samples had larger absorption depth and area values. The absorption depth and area of the pure white spots at 530 nm was highly correlated with redness, but the red surface and pure white spot spectra exhibited considerably different redness values, absorption depths, and absorption areas at 525–530 nm. Thus, these are advantageous parameters for distinguishing between the two surface types. The absorption positions of the red surfaces, orange surfaces, and pure white spots in the visible spectrum differed considerably, which is likely related to changes in the iron mineral types and contents present in the strata. Compared to the red surface absorption position at 525 nm, that of the orange surface shifted in the shortwave direction to 500 nm, which may be related to lower hematite and higher goethite contents. The absorption of the pure white spots at 430 nm may be caused by their pyrite content. The absorption depths of black, blocky, and green plants at 670 nm were considerably correlated with Normalized Difference Vegetation Index(NDVI). The NDVI values and absorption depths of the three plant types had widely differing range distributions, which can serve as a basis for distinguishing among the three plant types. The absorption depths of non-white spot and white spot plant coverings at 670 nm also increased with increasing NDVI values. The absorption positions of pure white spots in the visible spectrum were 430, 530, and 690 nm. After plants attached to the white spots, the 430 nm absorption position disappeared while that at 530 nm shifted in the shortwave direction. The absorption position at 690 nm was converted into that of chlorophyll. This study provides a reference for quantitatively investigating the color tones of the Danxia rock walls using VNIR reflectance spectroscopy.

[Objective] This study was aimed to estimate the amount of water conservation in Shaanxi Province. [Methods] The InVEST model and PLUS model were coupled to calculate the water conservation amount in Shaanxi Province from 2000 to 2020 and predict the water conservation amount under land use changes in the future in 2030. [Results] The average water conservation amount in Shaanxi Province from 2000 to 2020 was 132.25 mm, with a spatial distribution characteristic of gradually increasing water conservation from north to south. From the perspective of vegetation types, forest land was the main body of water conservation in Shaanxi Province. The average annual water conservation amount was 199.55×108 m3. From the administrative region, Ankang City had the largest water conservation amount(308.96 mm). The total amount of water source conservation in 2030 will be 285.16×108 m3 and 8.68×108 m3 less than that in 2020. [Conclusion] The water conservation amount of Shaanxi Province will show a slight downward trend from 2020 to 2030 in the future.

[Objective] Exploring the impact of household income on household energy consumption and energy poverty from the perspective of mental account can provide a theoretical basis for solving the contradiction between the increase of household income and the coexistence of low energy consumption level and high energy poverty in China. [Methods] Based on the China Family Panel Studies (CFPS) data from 2016 to 2018, this study measured the energy poverty in China, and then explored the impact of household income on household energy consumption and energy poverty from the perspective of mental account. [Results] (1) At present, China’s energy poverty is relatively serious. An increase in household income can promote household energy consumption and reduce energy poverty. (2) There is a mental account effect in Chinese households, and energy consumption and energy poverty are mainly affected by the wage income account and business income account. (3) The results of the mechanism analysis show that the wage income account and the business income account can promote the household energy consumption and reduce the incidence of energy poverty by increasing the willingness of household energy consumption and willingness of improving household energy facilities. (4) The results of heterogeneity analysis show that for households with higher energy consumption threshold, lower household income, and being in the eastern region, the mental account of income has a more significant impact on their energy consumption and energy poverty. [Conclusion] Therefore, for the current phenomenon of low energy consumption and high energy poverty in China, we should pay attention to the difference in household income sources, focus on increasing the wage and business income of households, further reduce the cost of household energy consumption, and increase the willingness of household energy consumption.

[Objective] To scientifically understand the spatio-temporal evolution process and formation mechanism of urban space, agricultural space and ecological space in Qinling-Daba Mountain area is the key to promote the overall coordination of the national spatial development pattern and the rise of the central and western regions, and it is also an urgent need for high-quality transformation and development of the region. [Methods] Based on the methods of spatial transfer matrix, topographic location analysis and random forest regression, the spatial and temporal evolution characteristics and driving mechanism of Qinba Mountain region during 2000—2020 were studied from two dimensions of “pattern scale-topographic location”. [Results] (1) In the past 20 years, the cities and towns in the Qinba Mountain area expanded dramatically, and the agricultural and ecological space continued to shrink. While the population of 58.33% of the counties decreased, the urban land was still expanding, and the “total population and urban size” showed a serious polarization. (2) The phenomenon was characterized by urban and agricultural space “climbing up the hills”, while ecological space “descended into the valleys”. The newly added urban and agricultural space was moved up 1 to 2 topographic positions on average. The dam elevation project of Danjiangkou Reservoir downstream had a significant impact on the overall spatial distribution gradient of the mountainous areas. (3) The dynamic adjustment and replacement of “agricultural space to ecological space” was the leading type of transformation in Qinba Mountain area, and the influence of fiscal expenditure was the most significant. Agricultural space was the main source of new towns, and the scale of urban degradation into agricultural and ecological space was significant in Qinba mountain area. (4) Land development policies, mountain terrain attributes, traffic location conditions and social and economic factors jointly restrict and affect the results of territorial spatial evolution in Qinba Mountain area, and there were obvious differences in the effect intensity and the number of significant factors of various types of factors in different conversion directions. [Conclusion] Promoting the concentration of new towns to the key development zones, scientifically guiding agricultural and ecological space to conform to the topographic gradient layout, carefully carrying out water conservancy project construction, and planning the overall regional layout of the “Three districs and Three lines” will have a positive impact on the optimization of territorial spatial pattern in Qinba Mountain area.

The comprehensive utilization of coal gangue is low, and this causes serious environment problems and security risks. The physical and chemical properties of coal gangue were analyzed in this paper, and the estimated value of different chemical components of coal gangue was counted. The physical properties of coal gangue aggregate were analyzed, and performance and its influencing factors of base course mixture with coal gangue aggregate were studied. The influence of coal gangue powder and coal gangue aggregate on performance of asphalt mortar and asphalt mixture was analyzed, and possible influencing factors and function mechanism were discussed. The results showed that heavy metal elements of coal gangue applied into asphalt pavement is not seeped out. The crushing value, water absorption and flat elongated particles content of coal gangue aggregate are generally high, but the compressive strength of base course with coal gangue aggregate is verified to meet the strength requirement. The performance, volume stability and durability of base course with coal gangue aggregate are closely related to aggregate gradation, the type and dosage of cementations materials and aggregate. The high temperature performance, temperature susceptibility and viscosity of asphalt mortar are improved by the addition of different coal gangue powder, and improvement effect of activated coal gangue powder on asphalt mortar performance is better. The low temperature performance and adhesion property of asphalt mortar with chemical activated coal gangue powder are improved. The physical reaction between asphalt and different coal gangue powder is only taken place. The temperature stability of asphalt mixture with coal gangue coarse aggregate has achieved the specification requirement. The water stability and low temperature fracture performance of asphalt mixture with fine aggregate replaced by coal gangue are improved. However, the high temperature performance of above mixture is lower than conventional hot mix asphalt mixture. The research results will provide reference for coal gangue applied into asphalt pavement.

To evaluate influence of external environment and material composition on skid-resistance durability of high viscosity modified asphalt (HVMA) mixture, the accelerated abrasion test was selected to simulate decay of skid resistance for asphalt mixture by setting different test conditions. The influence of aggregate gradation, asphalt type, ambient humidity and overload on skid-resistance durability of asphalt mixture was discussed, and the significant effect of selected factors on skid-resistance durability of asphalt mixture was revealed. The results show that the skid-resistance durability of SMA-13 (Stone Mastic Asphalt) mixture is better than OGFC-13(Open Graded Friction Course) and PA-13 (Porous Asphalt) mixture under different conditions, and attenuation rate of different indexes of SMA-13 mixture is 1.6–2.2% and 0.8–2.1% lower than compared with OGFC-13 and PA-13 mixture. The attenuation rate of texture depth for asphalt mixture is closely related to aggregate gradation and asphalt, but the attenuation rate of british pendulum number for asphalt mixture with the same mineral aggregate is only significantly affected by the asphalt. The skid resistance of SMA-13 and PA-13 mixture is improved slightly by addition of high viscosity modified asphalt. The attenuation rate of texture depth of SMA-13 and PA-13 mixture with HVMA is reduced about 0.6–3.0% and 2.2–4.2% than SBS modified asphalt, but the attenuation rate of british pendulum number of above mixtures is increased about 1.2–1.6% and 0.3–1.7%. The skid-resistance durability of asphalt mixture with TPS (TAFPACK-Super) and SINOTPS high viscosity agent is better than HVA (High viscosity additive). The skid-resistance durability of asphalt mixture based on texture depth is improved under wet condition. However, the skid-resistance durability of asphalt mixture for british pendulum number gets worse due to water intrusion. The skid-resistance durability of asphalt mixture is rapidly decreased under overload condition. The influence of overload and SBS modified asphalt on skid-resistance durability of asphalt mixture is higher than ambient humidity and HVMA. This paper will provide foundation for high viscosity modified asphalt applied in asphalt pavement.

Parkinson's disease (PD) is a common neurological degenerative disease in clinical practice. Dysarthria is a common motor symptom, with a high incidence and diverse clinical manifestations. PD patients often ignore their dysarthria symptoms until they reach the decompensation stage, and only a small number of patients receive treatment. This article reviews the pathogenesis, evaluation and treatment of dysarthria in PD, providing theoretical basis for early diagnosis and timely treatment of dysarthria in PD.

The replenishment of water resources in a space station is essential for achieving an astronaut's long-term and on-orbit residence. Recycling his or her urine is one of important and major ways of wastewater recovery. However, traditional urine treatment methods have the disadvantages of equipment that takes large space, complex procedures and low atomic utilization. Therefore, this paper designs a novel wastewater reuse system that treats urine based on urea electrooxidation technology, introduces methane fuel cell coupled with the Sabatier reactor and hydrogen-oxygen fuel cell to further utilize urine treatment products and to allocate water resources precisely in the space station through designing grading treatment and dynamic control systems. The wastewater reuse system designed in the paper contributes to saving valuable space and reducing energy consumption during urine treatment, thus improving water recovery rate and optimizing resource allocation.

The ablation fault of buffer layers in high-voltage cables is a frequent type of cable fault in recent years. However, current detection methods for ablation defects cannot meet the detection requirements of existing cables. In this paper, the ultrasonic detection method for the buffer layer ablation defects in high-voltage cables based on the surface roughness of aluminum sheath is studied for the first time. Firstly, simulated buffer layer ablation experiments under humid conditions are carried out, and the laser confocal microscopy and electrochemical impedance spectroscopy analysis are carried out on the ablated aluminum specimens. It is found that with the increase of ablation time, the surface roughness of aluminum specimens gradually increases, and the surface corrosion degree of aluminum specimens gradually deepens, corresponding to the aggravated ablation defects of buffer layers, which indicates that the surface roughness of aluminum specimens could be correlated with the ablation degree of buffer layers under the moisture conditions. Secondly, ultrasonic testing experiments are carried out on the ablated aluminum specimens, and the roughness of the corroded surfaces of aluminum specimens can be calculated from the amplitude ratio of adjacent ultrasonic echo signals. The calculated results show the same variation trend as the measured roughness in the experiment. The results in this study indicate that the ultrasonic tests could be used to detect the severity of buffer layer ablation defects, providing the research basis for the ultrasonic detection method of ablation defects in the buffer layer of high-voltage cables.

Background Oral lichen planus (OLP) is a common oral mucosal disease, clinically categorized into erosive OLP (EOLP) and non-erosive OLP (NEOLP) based on symptoms, but its pathogenic mechanism remains unclear. This study aims to explore the relationship between OLP and the oral microbiome.Methods We collected oral mucosal samples from 49 patients and 10 healthy individuals and conducted 16S rRNA and ITS gene sequencing to explore the oral fungal and bacterial communities.Results We observed significantly lower α diversity of fungi in the EOLP group, with Candida being significantly enriched as the main dominant genus. In the NEOLP group, Aspergillaceae were significantly enriched. The EOLP group showed significant enrichment of Aggregatibacter and Lactobacillus, but the relative abundance of Streptococcus was notably lower than in the other two groups. In the NEOLP group, two species including Prevotella intermedia were significantly enriched. The microbial co-occurrence and co-exclusion networks display distinct characteristics across the three groups, with Lactobacillus assuming a significant bridging role in the ELOP group.Conclusions Our study indicates that EOLP and NEOLP experience varying degrees of dysbiosis at both the fungal and bacterial levels. Therefore, the pathogenic mechanisms and interactive relationships of these microbiota associated with OLP merit further in-depth investigation.

Heated tobacco products (HTPs) are a recent category of tobacco products, with their relative safety compared to cigarette smoking and potential to help smokers to quit being two reasons why regulators may consider their market approval. Designed to heat tobacco rather than to burn in order to produce aerosol, different heating techniques are applied to commercial HTPs, which may result in differing aerosol formation. Therefore, each product requires separate assessment. This work focuses on a closed-end HTP (coded as HTP-A), which is electrically heated and designed to allow puffing air flow to bypass its tobacco section, resulting in reduced oxygen concentration within the tobacco section during heating and aerosol forming. To provide a preliminary aerosol chemistry and in vitro toxicological screening, this study assessed HTP-A against a commercial electrically heated HTP (IQOSTM, coded as HTP-B) and a 3R4F reference cigarette. Under Health Canada Intense (HCI) smoking regime, the levels of 9 regulatory priority toxicants in the aerosol of HTP-A were either reduced or comparable to those in HTP-B on a per-stick basis. Additionally, both HTPs showed significant reduction (greater than 90%) in comparison to those measured in mainstream smoke of 3R4F cigarette for these toxicants. Using a set of standard in vitro toxicological assays (Ames, Micronucleus and Neutral Red Uptake), the two HTPs showed no observable responses while significant toxicity responses were recorded for 3R4F’s total particulate matter. Based on these preliminary results, the novel closed-end HTP-A design may provide similar toxicological profiles to the comparator HTP-B. Further toxicological and clinical assessments are warranted to evaluate HTP-A’s potential for exposure or disease risk reduction. [Contrib. Tob. Nicotine Res. 32 (2023) 146–156]

Pancreatic cancer (PC) is a highly malignant digestive system tumor with a poor survival rate and prognosis. Most patients with pancreatic cancer have no obvious clinical manifestations in the early stage of the disease, and are found to be in the middle and late stage of the disease when they seek treatment.A unique and complex tumor microenvironment (TME) is formed during its development and evolution. Due to the occult nature of pancreatic cancer, for patients with advanced pancreatic cancer, some traditional treatment methods such as surgical resection and chemotherapy are very limited, and there is a lack of effective treatment programs. Of course, this is also related to the immunosuppression of the TME of pancreatic cancer. Some immunosuppressive cells, such as myeloid-derived suppressor cells (MDSCs) and regulatory T cells (Tregs), play an important immunosuppressive role in helping tumor immune escape. Therefore, it is considered to be a major difficulty in the treatment of pancreatic cancer. In recent years, with the in-depth study of TME, immunotherapy has gradually become a new therapeutic strategy, and has made great progress in the treatment of various malignant tumors. The study found that targeted MDSCs therapy is a new and effective treatment for pancreatic cancer.In this paper, we introduce the role of MDSCs in TME and their progress as potential targets for immunotherapy of pancreatic cancer, hoping to provide new directions for the treatment of pancreatic cancer and other tumors.

To evaluate the effects of varying proportions of yak meat in feed on the growth of rats and provide a theoretical basis for selecting the optimal feed proportion suitable for rats. This study was designed as a one-variable experiment. Fifty male rats were divided into five groups. The ratios of yak meat to basal feed of rats in four dietary treatment groups were 2:8, 4:6, 6:4, and 8:2, respectively, while those in the control group were only provided a basal diet. In the feeding experiment, the body weights of the rats were recorded on Day 0 and subsequently in the first, second, third, and fourth weeks, along with quantities of feed intake. The body and tail lengths, as well as the waist circumference of the rats, were measured, and blood samples were collected in the fourth week for routine blood and biochemistry investigations. The rats in the 4:6 feed group had the best body condition. They had normal body and tail lengths, smaller waist circumferences, good posture, and were in better overall health than rats in the other groups. The results indicate that the 4:6 diet was optimal for enhancing rats’ growth performance compared to the other diets.

The arrival of the big data era, which has been widely used in various industries. In today’s education management mode, in order to improve education development, it is necessary to keep up with the times and reform the education management mode. For this reason, this paper designs an education management model based on the classroom behavior recognition model, which manages students in real time by detecting their classroom behavior status. The classroom behavior recognition model is improved based on the deep learning target detection SSD algorithm. A lightweight model for detecting the behavior of SSD-M3-SFP networks has been designed by replacing the SSD backbone network, VGG, with a MobileNetV3 network after pruning SFPs. Both the speed and accuracy of student behavior recognition can be ensured by the model. Through practical analysis, in the before-and-after analysis of SSD-M3-SFP-based education management model and general education management model, the p-values are 0.001, 0.003, 0.000 on the indicators of the three aspects of education management services, all of which are lower than 0.05, and the difference is significant, and the management effect of SSD-M3-SFP-based education management model is higher than that of general education management model.

The differences in the chemical composition of Morus nigra (M. nigra) extracts from four different extraction methods, ultrasound-assisted extraction with pure water (WU), pure water decoction extraction (WD), ultrasonic-assisted extraction with formic acid water (FAU), and pure water heat reflux extraction (WHR), were identified using ultra-high performance liquid chromatography-quadrupole time-of-flight tandem mass spectrometry (UPLC-Q-TOF-MS/MS) technology.

Cigarette ventilation characteristics are one of the important design factors that affect the combustion state and therefore smoke release. In order to study the changes of ventilation characteristics and the combustion state of cigarettes with different rod circumferences during smoking, a device was designed that could flexibly measure the different ventilation characteristics along the cigarette rod. The device was utilized to measure the changes of the total ventilation rate and filter ventilation rate of cigarettes with different rod circumference in both burned and unburned conditions. At the same time, a test method was implemented to measure the temperature of the combustion coal puff-by-puff during the smoking process. The relationship between ventilation and the combustion state was analyzed on a per-puff basis. The results show that with the decrease of the rod circumference from 24 mm to 20 mm and 17 mm, the total ventilation rate under burning conditions changed considerably compared with unburned conditions, increasing by 55.7%, 60.5% and 74.5% on average, respectively. The ventilation of the cigarette paper played a major role in regulating the ventilation during puffing. With the increase from 17 mm to 24 mm in circumference, the combustion efficiency of the tobacco decreased as indicated by a range of thermophysical parameters of the burning coal.

16MnNiV steel is developed from 16Mn and 16MnV steel. After hot-perforated rolling into tube, cold rolling, cold drawing and heat treatment are carried out to prepare high pressure tubes with high caliber. The microstructure and mechanical properties of 16MnNiV seamless steel tube of small diameter were studied by means of optical microscopy (OM), scanning electron microscopy (SEM), electron backscattering diffraction (EBSD), transmission electron microscopy (TEM) and physicochemical phase analysis. The microstructure and the change of the second phase precipitation were revealed, and the strengthening increment was calculated. The relevant results can provide a reference for the material development and performance improvement of high strength high pressure tubes. The results show that the main structure of the experimental steel in the process of drawing the tube is ferrite and pearlite. In the case of precipitation, annealing after one pull increases the total amount of precipitation, and annealing after the second pull does not change the total amount of precipitation. It is known from EDS analysis that the precipitated second phase particle is VC. The tensile strength and yield strength of the experimental steel are gradually increased and the elongation rate decreases after cold drawing and different heat treatment processes. It can be seen that the increase of yield strength of experimental steel mainly comes from the contribution of fine crystal reinforcement due to the large deformation of cold extraction process. After heat treatment, the tensile strength, yield strength and elongation rate of ϕ6.35 mm×3 mm round tubes reach over 960, 864 MPa and 15.5%. Compared with other high pressure tubing products of 16Mn series, the mechanical properties are greatly improved and good strong plastic matching is obtained.

In order to improve the small intestinal digestibility of rice analogues (RA) and to enhance the nutritional value of the product, rice and potato flour blends were used as raw materials to prepare RA by direct extrusion modification using chemical or biological modifiers combined with high-temperature puffing. The internal structure and nutritional characteristics of RA were analyzed. The results showed that potato starch and amylase enhanced the digestive resistance of RA. The tested chemical modifiers mainly affected the structure and physicochemical properties of starch, in turn increasing the apparent viscosity and decreasing the degree of hydrolysis and digestibility of RA. Octenylsuccinic anhydride (OSA) played a promoting role in the initial stage of intestinal digestion. Propylene oxide (HPPO) reduced the particle size and increased the storage modulus (G’) of RA. Sodium trimetaphosphate (STMP) increased the particle size and G’ of RA. α-Amylase promoted the decomposition of large particles, led to even distribution of proteins on the surface of particles, and inhibited digestion. High-temperature expansion promoted starch decomposition in the early stage of intestinal digestion. Digestion results showed that the combinatorial effect of extrusion modification and high-temperature puffing weakened the film-forming capability of potato starch, which effectively inhibited the decomposition of the starch and weakened the digestive reaction when it just entered the intestine.

The detection of traffic congestion is now realized mostly by human monitoring and sensor monitoring. However， such detection devices are deficient in road-occupied electric power construction. To meet the needs of low equipment dependency and high accuracy of congestion detection in the road-occupied electric power construction， a detection method based on video data is proposed， which uses neural networks to extract features from video data and determine whether there is traffic congestion. In response to data deficiency in the road-occupied electric power construction， the generalization of the network is improved by making full use of the generic traffic scene dataset， and the adaptive learning method based on domain adversarial neural networks （DANN） is used to reduce the differential performance of two data domains in the feature extraction network. Semi-supervised learning （SSL） is proposed to reduce the manual labeling workload. The experimental results show that the proposed method can achieve an accuracy of 93.2% in traffic congestion detection and recognition in road-occupied electric power construction and has high application value.

Objective: This paper discusses the feasibility of using mineral element fingerprinting technology of to identify tobacco producing areas, screens out the effective indicators, and constructs the discrimination model of tobacco producing areas. Methods: The contents of 20 mineral elements in tobacco leaves from 11 producing areas were simultaneously determined by ICP-MS, and the data were analyzed by variance analysis, cluster analysis, principal component analysis and discriminant analysis. Results: The contents of 16 elements were significantly different among producing areas, and principal component analysis resulted in 6 principal components, with the cumulative variance contribution of 89.253%. Using linear discriminant analysis, four elementsmineral, K, Mn, Se and Ba, were screened as the effective indicators to discriminate the geographical origin of tobacco leaves. The established discriminant model could accurately distinguish tobacco leaf samples from different tobacco producing areas. Conclusion: Significant differences were showed in the contents of mineral elements in tobacco leaves from 11 producing areas. Four elements, K, Mn, Se and Ba, are important indicators for distinguishing tobacco producing areas. Mineral element fingerprinting technology can be used for distinguishing tobacco producing areas.

The calcined product of the high-level liquid waste(HLLW) is the intermediate product of two-step cold crucible glass solidification process. Its performance(such as water content, bulk density, denitration efficiency and so on) has an important impact on the process control of the whole system and glass product quality. Generally, the factors affecting the performance of calcined products include: the heating temperature of rotary calciner, the inclination angle of furnace body, the rotation speed of furnace body, the composition of simulated waste liquid, etc. In order to obtain the influence degree of different calcined products on their performance, the Gauss Kriging(GP) surrogate model is used to calculate and analyze the influence factors on the experimental data of the transformation process carried out on the bench for the simulated HLLW of spent fuel with burnup of 33 GW·d/t U and 45 GW·d/t U. The results show that the main influencing factor seqencing of the bulk density of calcined products under the experimental conditions is the composition of simulated liquid waste>the angle of furnace body>the rotation speed, and the main influencing factor seqencing of water content is the angle of furnace body> the composition of simulated liquid waste> the rotation speed. At the same time, the established proxy model is used to predict the water content and bulk density of calcined products produced by four heating temperatures, five inclination gradients and two simulated waste liquid component tests in the high-level waste liquid transformation test. It shows that is more suitable for the performance of calcined products, as the heating temperature in the first two areas between 540-680 ℃, and the angle of furnace body with 3%. Therefore, the method of identifying the factors affecting the performance of calcined products by agent model method is feasible, and can provide basic data and technical support for the optimization process.

The outer ring spalling failure angle position of the rolling bearing has an important influence on the vibration size and service life of the rotating machine. It is necessary to judge the outer ring spalling failure angle within the load-bearing interval. Based on the peak change law of the acceleration vibration signal, a fault location method was proposed for ball bearing outer ring spalling. This method established the Lagrangian dynamic equation with time-varying impact force. By analyzing the change trend of the contact force in the bearing area of the ball bearing, the law of the peak ratio of the absolute value of the vibration acceleration signal was obtained by analogy, and the impact point of the acceleration vibration signal was analyzed. For nearby locations, a new judgment index was proposed, and the specific location of the fault was obtained. Simulation and experiment results show that there is a corresponding functional relationship between the horizontal vertical synchronization peak ratio of the vibration signals at different positions of the ball bearing outer ring spalling fault. Simulation and experiment verify the accuracy of the positioning law. It provides a theoretical basis for the diagnosis method to determine the location of the ball bearing outer ring spalling fault location.

The service life of the planetary reducer in a hub drive system largely depends on the system reliability design. Aimed at the problems of lower credibility and inadequate depth in the reliability allocation, based on improved FMECA formulas and order statistics theory, an advanced reliability allocation method of the planetary reducer is proposed. The basic characteristics of the planetary reducer are analyzed, and FMECA formulas with the positive failure correlation modifying operator are presented, which indicate that the subsystem complexity and the failure occurrence change in the same direction as the failure correlation degree, respectively. Simultaneously, based on the Gumbel Copula function and order statistics theory, the reliability allocation model is established to assign reliability design indices to parts of the planetary reducer. By comparing the subsystem reliability allocation weights obtained by different methods, results show that the allocation result of the proposed method is more credible. It will be helpful to accomplish the deeper reliability allocation and improve the service life of the planetary reducer.

Aim/purpose – Cultural differences play an influential role in driving tourism development and varying outcomes of technology acceptance. The impact of ChatGPT on tourism is yet to be explored. Therefore, this study discussed how ChatGPT may influence tourism development and management in different cultural contexts.

We present the electronic properties of InAsNBi with N and Bi concentrations based on 16×16 band Hamiltonian model. This model is extended from Band Anti-crossing (BAC) and the dimension of basis states used in the Hamiltonian matrix is 16. Under the condition that the quaternary compound matches the lattice configuration of the InAs substrate, the variations of band gap (Eg), spin-orbit coupling energy (ΔSO) has been examined as a dependency on the mole fractions of N and Bi. Our findings indicate the integration of N and Bi atoms in InAs gives rise to a substantial band gap energy minimization and the growth of spin-orbit coupling energy. Subsequently a crossover (ΔSO = Eg) is observed at a Bi concentration of 0.37%, which contributes to enhancing the effectiveness of photonic devices by suppress Auger recombination. We further reveal the band offset with different N and Bi concentrations and considered the influence of the substrate on the material deviation. The conduction band energy mislignment (ΔEc) of InAsNBi exceeds energy misalignment in the valence bands (ΔEv), which is required to improve thermal-insensitive characteristics of semiconductor devices. Moreover, the significant mastery over the edges of the conduction and valence bands by adjusting the concentration of N and Bi will increase the flexibility to design InAsNBi/InAs structures.

A novel concept is described here that utilizes externally applied heat to a solid rod of reconstituted tobacco biomass to form a stream of aerosol under progressively oxygen-deficient atmosphere. The boundary of auto-ignition was determined at oxygen concentrations of 0%, 5%, 10%, and 21% and then the effects of these different atmospheres on various parameters were studied. Experimental results indicated that the ignition temperature decreased with the increase of oxygen concentration and a negative temperature coefficient (NTC) for atmosphere with oxygen was observed at before but close to ignition temperature. Significant differences in the yields of CO and CO2 between oxygen and oxygen-free atmosphere were observed. The mass of aerosol produced under an inert atmosphere and reduced-oxygen atmosphere were characterized with selected volatile and semi-volatile components, phenols, aldehydes, and other organic compounds of interests. In addition, higher oxygen concentration resulted in higher bulk and surface oxygen content of solid-phase residue, the reduction of carbon and hydrogen element content and related functional groups, and the content of inorganic compounds also exhibited an increase with oxygen concentration. By systematically changing oxygen concentrations of the biomass bed with increasing temperatures, an aerosol stream of controlled chemical composition and yields could be formed without leading to ignition. Key chemical markers of inhalation harm were measured and compared to each other under different degrees close to combustion. Studying reconstituted tobacco or other biomass materials in such a way could provide alternative and useful information in the design heated biomass aerosol generators.

A lit cigarette forms a positive and negative pressure zone by a puff with respect to the position of its paper burn line. Smoke aerosols generated from the two zones are then pulled through the rod under the puff to form the mainstream smoke. This phenomenon is fundamental to the thermophysics and the resultant chemical composition of the mainstream smoke. In this study, we created two different airflow pathways inside a heated tobacco rod by a puff, and investigated the differences in aerosol formation and its chemical compositions. The two different pressure-induced conditions, one through an open-ended tobacco rod (marked as HNB, a label of a designed airflow pathway of commercial heated tobacco products called heat-not-burn prior), and the other through a closed-ended tobacco rod (marked as NSC, a label of a novel-designed airflow pathway of heated tobacco products), were compared for their aerosol collected mass (ACM), the contents of nicotine, water and added aerosol agents such as propylene glycol (PG) and glycerol (VG), as well as selected aldehydes and ketones in the mainstream aerosol. Aerosol particle distribution and the heated temperature along different rod locations were also compared during a puff. The results indicated marked differences in the aerosol formation processes between the two HNB and NSC systems. The transfer ratios of the main aerosol components were significantly higher for the NSC; the levels of formaldehyde and acetaldehyde were significantly lower under the NSC than the HNB condition. There were also significant differences for the aerosol particle number concentration (APNC) and count median diameter (CMD) for the two systems. The lack of convective heat transfer in the aerosol formation under the NSC condition resulted in a relatively stable thermal aerosol generation zone, reflected by the temperature difference between the two systems in the selected locations. The NSC mode of tobacco heating thus offers a novel and enhanced aerosol generation for heat tobacco product designs.

Objective To explore the prediction accuracy of prosthesis size of the modified 3D printed patient-specific instrumentation (PSI)-assisted total knee arthroplasty (TKA) by comparing the difference between intraoperative prosthesis size and preoperative planned prosthesis size. Methods We optimized and improved the workflow, design scheme, shape of guide, operation technology and verification method of the traditional PSI-assisted TKA. A total of 126 patients (137 knees) who received 3D printed PSI-assisted TKA based on preoperative CT images in our center were recruited in this study. The differences between the actual prosthesis size and the preoperative planned size were compared and analyzed. Results All patients completed the surgery successfully, and no serious complications occurred. For the femoral side, the difference between the actual used size and the doctor's planned size was observed in 7 cases, and the difference between the actual used size and the engineer's planned size was in 25 cases (P < 0.01), and the engineer's planned size adjusted by doctors was 19 cases (P < 0.01). For the tibial side, the actual used size and the doctor's planned size was 39 cases, the difference between the actual used size and the engineer's planned size was 44 cases, and the engineer's planned size adjusted by doctors was 5 cases. Conclusion The planned prosthesis size in Our modified 3D printed PSI-assisted TKA is consistent with the intraoperative prosthesis size, and the plan will be more consistent after adjustment by the doctors. [Key words]Objective To explore the prediction accuracy of prosthesis size of the modified 3D printed patient-specific instrumentation (PSI)-assisted total knee arthroplasty (TKA) by comparing the difference between intraoperative prosthesis size and preoperative planned prosthesis size. Methods We optimized and improved the workflow, design scheme, shape of guide, operation technology and verification method of the traditional PSI-assisted TKA. A total of 126 patients (137 knees) who received 3D printed PSI-assisted TKA based on preoperative CT images in our center were recruited in this study. The differences between the actual prosthesis size and the preoperative planned size were compared and analyzed. Results All patients completed the surgery successfully, and no serious complications occurred. For the femoral side, the difference between the actual used size and the doctor's planned size was observed in 7 cases, and the difference between the actual used size and the engineer's planned size was in 25 cases (P < 0.01), and the engineer's planned size adjusted by doctors was 19 cases (P < 0.01). For the tibial side, the actual used size and the doctor's planned size was 39 cases, the difference between the actual used size and the engineer's planned size was 44 cases, and the engineer's planned size adjusted by doctors was 5 cases. Conclusion The planned prosthesis size in Our modified 3D printed PSI-assisted TKA is consistent with the intraoperative prosthesis size, and the plan will be more consistent after adjustment by the doctors.

Objective To evaluate the mid-term clinical efficacy of total hip replacement using a standardized 3D printed porous trabecular titanium acetabular cup. Methods Clinical data of 23 consecutive patients undergoing total hip replacement with a standardized 3D printed porous trabecular titanium acetabular cup (25 arthroplasties) between February 2016 and August 2018 were collected and retrospectively analyzed in this study. All patients were followed up for 39~69 (51.7±10.7) months. Efficacy evaluation indicators included incidence of postoperative complications and survival rate of prosthesis, as well as visual analog scale (VAS) score, Harris score, acetabular side imaging evaluation and cup survival rate at 6 months after operation and last follow-up. Results No complications were observed in all 25 hip replacements, and the survival rate of cup was 100% during the whole follow-up. The VAS scores were decreased significantly at 6 months postoperatively (1.44±0.82) and last follow-up (0.08±0.27) when compared with the scores preoperatively (7.48±0.96, P < 0.05). The Harris scores were increased significantly at 6 months postoperatively (86.88±3.52) and last follow-up (95.04±1.86) than the pre-operative scores (45.64±4.55, P < 0.05). There were no significant differences in postoperative VAS score and Harris score between the patients with and without periprosthetic radiolucent zone. Conclusion Standardized 3D printed porous trabecular titanium acetabular cup shows its favorable mid-term outcome in total hip arthroplasty, provides high acetabular survival rate, and has certain advantages in reducing aseptic loosening of the prosthesis.

Abstract Background Natural orifice specimen extraction surgery (NOSES) has the advantages of less postoperative pain, fast bowel function recovery, reduced hospital stay and better cosmetic effects. In our centre, anterior resection of rectal cancer with preservation of the left colonic artery (LCA) was performed using NOSES. The feasibility, safety and short-term clinical efficacy of the technique were discussed. Methods A retrospective analysis was performed on 19 patients who underwent laparoscopic anterior resection of rectal cancer with left colonic artery preservation and natural orifice specimen extraction in the Gastrointestinal Surgery Center of Sichuan Cancer Hospital from September 2018 to December 2019. General information about the patients, perioperative data and short-term postoperative results were analysed. Results All operations were completed smoothly, with an average operation duration of 304.36 ± 45.04 min, intraoperative bleeding of 76.31 ± 61.12 ml, first time off bed of 14.42 ± 3.56 h, first time to anus exhaust of 15.26 ± 8.92 h, first time to liquid diet of 2.94 ± 1.12 days, and average postoperative stay of 10.21 ± 3.13 days. Two patients developed temporary intestinal obstruction, and one patient developed pulmonary infection. All of them recovered well after active supportive treatment and were successfully discharged. Conclusion Laparoscopic NOSES for rectal cancer with left colon artery preservation is safe and feasible, with satisfactory short-term results, and is worthy of further clinical investigation.

Objective To discuss the strategy for cervical dumbbell⁃shaped tumors and develop a proposal for individualized therapy. Methods and Results Total 32 patients with cervical dumbbell⁃shaped tumors were recruited from The First Affiliated Hospital of Anhui Medical University from March 2017 to March 2022. All patients received surgical treatments, while the tumors located in C1-2 levels among 7 patients and C2-7 levels among 25 patients. Preoperative McCormick spinal cord function gradeⅠin 9 cases, gradeⅡin 12 cases, grade Ⅲ in 11 cases. Individualized surgical strategies were set according to the results of Toyama typing, preoperative imaging examination and intraoperative spinal stability. Surgery through posterior approach was performed in 26 cases, 2 patients underwent a lateral posterior sternocleidomastoid approach, 2 patients underwent surgery through combined posterior⁃anterolateral approach, and 2 patients received anterior cervical approach. Ninteen out of 32 patients with preoperatively unstable spinal factors or changes in spinal stability resulting from surgery received one⁃stage internal fixation. One patient underwent anterior cervical corpectomy and fusion followed by titanium cage implantation, and 18 patients underwent posterior trans⁃pedicle and lateral mass screw fixation. The results showed a gross total resection for all patients and the success rate was 100% (32/32). The average intraoperative blood loss was about 210 ml. Imaging examinations were performed for all patients within a week after the surgery, the internal fixator were all in good position. One month after the surgery McCormick spinal cord function gradeⅠin 20 cases, gradeⅡin 10 cases, grade Ⅲ in 2 cases. All patients had varying degrees of improvement in symptoms, no cerebrospinal fluid leakage, no serious nervous system infection and other complications, no postoperative cervical kyphosis, and no loosening or breakage of the screws and rods were found in 28 months after surgery, the bone graft fusion and vertebral body shape were good. Conclusions The size of the intervertebral foramen is one of the important factors to be considered in the surgical strategy of cervical dumbbell⁃typed tumors. The surgical management of C1-2 dumbbell⁃typed tumors is different from that of other levels, it is necessary to understand the patient's medical history, symptoms and signs in detail and to improve imaging evaluation before surgery. The development of multiple techniques and typing methods facilitate the development of individualized surgical plans.

In implementing the PMC model, trusting relationships between owners and PMC contractors is the key to resolving the dilemmas caused by institutional constraints and conventional thinking, such as frequent organizational conflicts, low management efficiency, and higher transaction costs. This study utilized PMC projects in Guangxi, Jiangsu, Zhejiang, Tibet, and Guizhou as analysis samples and employed semi-structured field interviews to investigate the antecedents of trust between owners and PMC contractors. In addition, questionnaires were used to quantify the mechanism of trust formation between the two parties and the influence of trust on project performance. The findings indicated that the managerial competence and reputation of the PMC contractor, the adequacy of the owner's authorization, and the effectiveness of the owner's supervisory measures were the key drivers of calculative trust. The adequacy of the owner's authorization, the effectiveness of the owner's supervisory measures, and social similarity play the greatest roles in influencing relational trust. Calculative and relational trust significantly impact project performance, with relational trust having a slightly more substantial impact. This study can serve as a resource for enhancing the performance of PMC projects and achieving PMC project success.

The differences in spatial-temporal distribution patterns and dominant driving factors of vegetation evolution among sub-regions during different historical periods were not clear. Therefore, this study introduced the gravity center model and geodetector to analyze the spatial-temporal change characteristics and dominant driving factors of normalized difference vegetation index (NDVI) in China during 1981–2019 from the perspective of geographic divisions. Results showed that (1) during 1981–2019, the average vegetation coverage in China showed an increasing trend and zones with obviously increasing vegetation NDVI were mainly distributed in the middle reaches of the Yellow River basin and the upper reaches of the Yangtze River. (2) During 1981–2019, the gravity center of national vegetation NDVI was mainly concentrated in Yan’an City and Tongchuan City, showing a southward migration trend as a whole, which indicates that the increment and growth rates of the southern part were greater than those of the northern part. (3) The growth of vegetation in southern China was primarily affected by the temperature, while that of northern China was largely influenced by precipitation. (4) During 1981–2019, the dominant interactive factors of vegetation change for all subregions changed greatly: natural factor (climate or terrain) ∩ other factors → landuse ∩ other factors.

The molecular dynamics method was employed to predict the tensile mechanical properties of polyether-ether-ketone (PEEK). Non-equilibrium tensile simulation with anisotropic pressure control was employed to obtain the stress-strain curve of PEEK, and to calculate the elastic modulus, yield strength and other mechanical properties. The influences of the strain rate and temperature on the mechanical properties, free volume, mean square radius of gyration (Rg), and energy for PEEK were investigated to explain the relationship between PEEK chain characteristics and macro mechanical properties. The results indicate that the elastic modulus and yield strength of PEEK significantly increase with the increase of strain rate, and significantly decrease with the increase of temperature. In the elastic and yield stage, free volume linearly increases, and Rg of PEEK chains remains steady, and the non-bonded energy results in the amount of the total potential energy increase. The interchain non-bonded interactions play a dominant role in the elastic and yield performance. Therefore, the amino modification strategy is investigated to improve the mechanical property of PEEK. It is found that the elastic modulus and yield strength of PEEK modified by amino are increased by 21% and 34% respectively than that of PEEK.

Abstract Background Childbirth preparation plays an important role in reducing maternal mortality and improving women’s childbirth experience. Evaluating childbirth readiness levels before and after interventions provides a basis for formulating more targeted and effective interventions. However, existing tools only assess partial childbirth preparation or have limited evidence of reliability and validity. The aim of this study was thus to develop a new instrument for use during the third trimester to comprehensively assess the readiness level of pregnant women, and test the scale’s psychometric properties. Methods The scale was developed through exploratory mixed methods including qualitative and quantitative phases. A literature review and in-depth semi-structured interviews were utilized to identify the scale items. A Delphi expert consultation evaluated the content validity. Psychometric testing was conducted in a convenience sample of 731 pregnant women in the third trimester (recruited from 3 tertiary hospitals in Hubei province in China). Item analysis was used to screen items; exploratory factor analysis was performed to extract factors; confirmatory factor analysis was performed to evaluate fit on the factor structures. Results The final scale consisted of four dimensions and 18 items that explained 65.8% of the total variance. Confirmative factor analysis (CFA) model showed that the 4-factor model fits the data well. The total Cronbach alpha coefficient of the total scale and 4 factors was 0.935 and 0.853–0.914. The split-half reliability was 0.880. The dimensions comprised “Self-management”, “Information literacy”, “Birth confidence” and “Birth plan”. Conclusions The childbirth readiness scale we developed has good reliability and validity, and can be used to comprehensively assess the readiness level of pregnant women. In addition to understanding the overall level of women’s childbirth readiness, using subscale scores, improvements can be targeted to specific areas of the preparation for childbirth, to improve the efficiency of the intervention.

With the rapid development of global industrialization, the pollution of hexavalent chromium (Cr(Ⅵ)) in soil and groundwater has become increasingly serious. Field investigation and laboratory tests were carried out for the soil polluted by the chromium slag of a ferroalloy plant. The adsorption, infiltration and dispersion experiments were conducted to study the adsorption characteristics and migration mechanism of Cr(Ⅵ) in silty clay. A three-dimensional kinetic mathematical model of Cr(Ⅵ) migration considering convection-dispersion-adsorption was established. The migration and distribution characteristics of Cr(Ⅵ) in groundwater with the pollution source located upstream or downstream of the contaminated site were obtained using the numerical approach. Meanwhile, the effects of dispersity and distribution coefficient) on the spatial and temporal distribution of Cr(Ⅵ) were revealed. The experimental results show that the Langmuir isotherm model well fits the adsorption data of silty clay. The maximum adsorption capacity of silty clay for Cr(Ⅵ) was 466.6 mg/kg. The hydraulic conductivity of silty clay under the infiltration of distilled water and 160 mg/L Cr(Ⅵ) solution was 6.5×10–7–6.7×10–7 cm/s, while it increased to 4.4×10–6 cm/s under infiltration of Cr(Ⅵ) solution with a concentration of 1 000 mg/L. The hydrodynamic dispersion coefficient (D) of silty clay was 1.4×10–4 m2/d. The value of the retardation factor ( ) was found to be 4.2–10. The results of the numerical simulation indicated that when the downstream was contaminated by Cr(Ⅵ), there was still a risk of pollution in the upstream even if molecular diffusion was not considered. The degree of pollution depended on the dispersity of the aquifer. Considering the adsorption of Cr(Ⅵ) by the aquifer, the higher the soil distribution coefficient, the smaller was the distribution range of the Cr(Ⅵ) pollution plume. Therefore, the transformation processes such as Cr(Ⅵ) adsorption should be focused on when predicting the distribution of Cr(Ⅵ) in contaminated sites.

During the active alignment focusing process of car camera assembly, lenses and holders need to be gummed by creamy white and translucent UV glue. The quality of glue dispensing can directly influence the performance of car cameras. Because of the translucency of UV glue, the glue dispensing image may present a low contrast situation, which increases the difficulty of vision detection. This paper proposes a method based on CycleGAN to enhance the glue dispensing image and effectively overcome the problems of blurred and low contrast edges. First, the glue part of the image is segmented into twenty regions. Second, the VGG16 model is used to divide the abovementioned twenty regions into high-contrast images and low-contrast images. Next, the CycleGAN model is trained to enhance the low-contrast images, and then convert them to high-contrast images. Finally, glue contours are extracted by using thresholding segmentation and edge detection to ensure that the quality of glue dispensing can be detected. The success rates of the VGG16 model and the CycleGAN model are 96% and 58%, respectively. The results show that the proposed method can effectively enhance the low contrast part of the glue region and improve the detection accuracy. Specifically, it can increase the gray value difference between the glue and the background from 20 to 55, while the background is substantially retained. The detailed information of the edges of the images is enriched. The accuracy of glue edge extraction can be increased to 99%, which is an approximately 75% improvement compared to the methods without enhancement.

In order to investigate the mechanical properties and failure mechanisms of the rock containing a single hole and double cracks, we used the 3D sand printing technique to prepare the rock-like specimens. Digital image correlation (DIC) method was employed to non-contactly monitor the deformation field of the specimens during the compression process. By calculating the convariance matrix of the horizontal, vertical and shear strains, we introduced the effective variance of the strain field to quantify and identify the failure behaviors of the specimens. The test results indicate that the mechanical properties of the standard 3D sand printed specimens are similar to those of natural sandstones, and the test data show a low dispersion. Therefore, they can be classified as a rock-like material. Due to the inclusion of the cracks, the mechanical properties of the specimens are degraded. The compressive strength and elastic modulus of the specimens each of which contains a single hole and double cracks are reduced by 8.04%-38.91% and 14.44%-27.78%, respectively, compared with those of the specimens each of which merely contains a single hole. Based on the DIC results, three basic types of cracks are identified successfully, i.e. tensile crack (Mode I), shear crack (Mode II) and mixed tensile-shear crack (Mode I-II). All the specimens each of which contains a single hole and double cracks show mixed tensile–shear failure (Mode I-II). The coalescence patterns between the hole and the cracks are influenced by their horizontal distance, and can be classified into tensile coalescence, rotation coalescence and mixed tensile-shear coalescence. The dispersion of the strain field can be quantified by the effective variance of strain field comprehensively. The effective variance of the strain field is close to zero at the initial crack closure stage and the elastic deformation stage. The cracks propagate in different manners after initiation. Based on the effective variance of the strain field, a quantitative method to identify the type of crack was proposed. The cracks can be identified as tensile crack, mixed tensile-shear crack, and shear crack, respectively, when the growth rates of the effective variance fall into the ranges of 0.72×10-2-1.89×10-2, 2.34×10-2-3.59×10-2, and 9.63×10-2-32.40×10-2, respectively.

A mesoporous material of Fe-Zr(P) was synthesized by modifying the bimetallic material of Fe-Zr with polyether P123. Then, TEPA(n)/Fe-Zr(P) was prepared by modifying Fe-Zr(P) with tetraethylenepentamine (TEPA). X-ray diffraction, infrared spectroscopy, X-ray photoelectron spectroscopy, N2 adsorption-desorption and thermogravimetric analysis were used to analyze the structure and thermal stability of the synthesized materials. The results show that P123 is remained in the pore channels of the support. Besides, TEPA was introduced to the surface of Fe-Zr(P) through the coordination between N and Zr species. The adsorbents filled with P123 and TEPA keep stable when the temperature is less than 182℃. In addition, the adsorbents exhibit good CO2 adsorption performance in a stream of 5% CO2 concentration. Over TEPA(n)/Fe-Zr(P), both of the hydroxyl and amine groups react with CO2, leading to the occurrence of CO2 chemical adsorption and the enhancement of adsorption capacity and N utilization. When the mass fraction of TEPA is 30%, a remarkable adsorption capacity of 211.3 mg/g and the utilization of N species of 62.7% are achieved at 75℃ in a stream of 10 mL/min. After 20 cycles of adsorption-desorption, the adsorption capacity keeps stable.

ObjectiveTo establish a method for the determination of selenium species in Se-enriched garlic with high performance liquid chromatography-inductively coupled plasma tandem mass spectrometry (HPLC-ICP-MS/MS).MethodsZORBAX SB-Aq column was used as analytical column; 10 mmol/L citric acid (ammonium citrate), 5 mmol/L sodium hexane sulfonate and 2% methanol were used as mobile phase for gradient elution. Baseline separation of selenate (SeO42−), selenite (SeO32−), selenocysteine (SeCys2), methylselenocysteine (MeSeCys), selenomethionine (SeMet) and Selenoethionine (SeEt) were completed in 10 min. Constant temperature oscillating assisted enzyme extraction was used to extract selenium species in garlic samples.ResultsThe detection limits for SeO42−, SeO32−, SeCys2, MeSeCys, SeMet and SeEt were 0.40, 0.40, 0.44, 0.47, 0.35 and 0.45 μg/kg, respectively. The linear correlation coefficients (r) were all above 0.999 in the range of 0-100.0 μg/L. Except SeCys2, the recoveries were between 79.0%-104.0% and the relatives standard deviations were within 2.2%-5.0%.ConclusionThe result showed that the method had good stability with high sensitivity and accuracy, and was suitable for determination of five selenium species in garlic.

In the numerical simulation of the macroscopic flow of the concrete, it can optimize the performance indicators of the screw conveyor and improve the uniformity of the material to be discharged in the batch production. The discrete element method is effective. The accuracy of physical parameters of this method is a key issue for the reliability of the simulation results of concrete. In this study, we measured the parameters describing the interaction between gravel, mortar, as well as between these two materials and the wall (steel). The experimentally determined parameters include the particle density, size, shape, coefficient of restitution, coefficients of static, and rolling friction. The cohesion coefficient of mortar particles for batch time was obtained by comparing the spread diameter and flow time in V-funnel experiments and simulation. After these calibration steps, the DEM parameters were validated by comparison of the mass flow rate and driving power by the batch production of screw conveying in simulations and experiments. The calculated results are proved to be close to the experimental data, which demonstrates that the measured DEM parameters are of sufficient accuracy to be used in the simulation of concrete flow performance (mass flow rate, energy consumption) in the screw conveyors.