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Objective: Effects of low-temperature plasma pretreatment assisted by ultrasound on the extraction of total flavonoids from ginger powder were studied, and its mechanism was preliminary discussed, and provided a new method for the extraction of total flavonoids from ginger powder. Methods: The single-factor tests and three-factor three-level response surface optimization tests were carried out with the yield of total flavonoids in ginger powder as the index and discharge power, treatment time and air intake volume of low-temperature plasma as factors. Meanwhile, the contents of 21 kinds of polyphenols in ginger powder were determined by HPLC before and after low-temperature plasma treatment, and the structure of ginger powder were characterized by scanning electron microscope (SEM) and Fourier transform infrared spectroscopy (FTIR). Results: The optimum extraction conditions for total flavonoids from ginger powder were as follows: Vacuum degree less than 100 Pa, discharge power of 295 W, treatment time of 60 s, air intake volume of 150 cm3/min, and the yield of total flavonoids was 26.9 mg/g. Chromatographic results showed that 21 kinds of polyphenols were separated with high precision (relative standard deviation，RSD≤3.75%), good stability (RSD≤4.25%), good repeatability (RSD≤4.75%) and accurate and reliable recovery rate (average recovery rate of 84.11%~100.86%). After low-temperature plasma treatment, total flavonoids content in ginger was increased, and phenolic acids content was decreased. Etching effect of low-temperature plasma increased the surface roughness of starch particles and cell wall fragments in ginger powder and led to the decomposition of lignin, which increased the contact area between solvent and ginger powder, and it was conducive to solvent penetration. Conclusion: Ultrasound-assisted low-temperature plasma treatment is an effective method to extract total flavonoids from ginger powder.

In response to the problems of large deformation, fracture closure and poor permeability of the surrounding rocks in the weak rock roadways of the 1 000 m or deeper coal mines, it is required that the grouting material has good injectability, fast solidification speed, high early strength, and strong bonding performance. A new method of synergistic preparation of inorganic grouting materials was designed using “component optimization + ultra-fine + nano-reinforcement + organic modification”. An inorganic grouting material with an optimum composition ratio of 50∶40∶10 for the ternary cementing system of calcium sulphate aluminate, gypsum and lime was developed. After ultra grinding, the compressive strength of the concretion increased by 163.0% within 4 hours, achieving initial early strength and rapid solidification. A nano-lithium-aluminium hydrotalcite reinforcement material with synergistic effects of nano-nucleation-induced crystallization and lithium ion promotion was developed, resulting in a 183.7% increase in the 2 h strength of the ultra grinding grouting material. The organic modifier with directional coupling effect at the coal-rock interface was synthesized, which formed a bridge through bonding with the grout and coal interface, significantly improving the bonding between the slurry concretion and the coal rock interface. The synergistically prodeuced inorganic-organic composite grouting reinforcement materials has small particle size (D95

In recent years, the demand for marine new energy, oil and gas, and transportation in coastal areas has increased significantly. The rigid demand for marine space resources has increased sharply, and the contradiction between supply and demand has become increasingly tense. In particular, the sea use of offshore wind power, affected by the national macro strategy, has shown a leap forward development, with the installed capacity ranking first in the world. The construction of large-scale offshore wind power has put forward higher requirements for the allocation of marine space resources. How to ensure the demand for offshore wind power and coordinate the contradiction between offshore wind power and other industries in the use of sea has become an important problem to be solved. Establishing the concept of intensive use of natural resources can solve the above problems well. The concept of intensive use is not only the internal requirement to comprehensively improve the utilization efficiency of marine space resources, the urgent need to solve the outstanding contradiction between protection and development, but also the key to coordinate the relationship between protection and development. Based on this, this paper aimed to systematically analyze the existing data of the sea area covered by offshore wind farms and the sea area for right confirmation, adopted the concept of intensive space resource development, and improved the sea area control index system for offshore wind power from the aspects of project site selection and submarine cable routing, wind farm design and technical requirements, sea use scope and area control for right confirmation, so as to improve the sea use intensive level of offshore wind power projects.

In order to alleviate the contradiction between human and land, and expand the city living space, the sea reclamation activities have been developed rapidly in a short time. However, while the reclamation projects have brought remarkable economic benefits, they have caused a lot of negative effects on marine environment and biological resources in the coastal areas.In this paper,the threats of sea reclamation activities on marine hydrological dynamic conditions, water quality, disaster prevention and mitigation were analyzed, and the damages to biodiversity, habitat protection and ecosystem service function value were discussed. The practical countermeasures were put forward, such as improving the management system of national policies and regulations on sea reclamation, strengthening research on ecological restoration planning, and establishing a system for assessing the impact of land reclamation on the ecological environment.

As the combine of cloud computing and Internet breeds many flexible IT services,cloud computing becomes more and more significant.In cloud computing,a user should be authenticated by a trusted third party or a certification authority before using cloud applications and services.Based on this,a protocol composition logic (PCL) secure user authentication protocol named UCAP for cloud computing was proposed.The protocol used a symmetric encryption symmetric encryption based on a trusted third party to achieve the authentication and confidentiality of the protocol session,which comprised the initial authentication phase and the re-authentication phase.In the initial authentication phase,the trusted third party generated a root communication session key.In the re-authentication phase,communication users negotiated a sub session key without the trusted third party.To verify the security properties of the protocol,a sequential compositional proof method was used under the protocol composition logic model.Compared with certain related works,the proposed protocol satisfies the PCL security.The performance of the initial authentication phase in the proposed scheme is slightly better than that of the existing schemes,while the performance of the re-authentication phase is better than that of other protocols due to the absence of the trusted third party.Through the analysis results,the proposed protocol is suitable for the mutual authentication in cloud computing.

This is an article in the field of ceramics and composites. Hydroxyapatite (HAP) has excellent ion exchange performance, shows good adsorption capacity for heavy metal ions, harmful anions, and organics in wastewater, and will not cause secondary pollution in the process of wastewater treatment. Thus, it is a promising green adsorbent. Due to its small size and large specific surface area, nano-hydroxyapatite (nHAP) exposes more adsorption sites, showing supreme adsorption capacity. It is a tendency to produce nHAP composites of strong adsorption capacity, easy for solid-liquid separation and regeneration, and low-cost. This article reviews the recent research progress of nano-HAP and its composites as adsorbents for wastewater treatment, and prospects the application of them as adsorbents.

The intelligent mine ventilation system is very important for the intelligent construction of coal mines. In order to solve the problem of missing mine ventilation parameter data caused by the lack of measurement conditions, instrument signal interference, uneven wind speed of roadway section, improper manual operation and other restrictive factors during actual measurement of mine ventilation parameters, a method for filling the missing data of mine ventilation parameters based on the multiple imputation method of random forest-chained equation was proposed. Multiple imputation with chained equations is used to generate n filled values for each missing attribute value by iterations, resulting in n complete datasets, and a final complete dataset is obtained by analyzing and optimizing the n complete datasets. In order to improve the filling accuracy of missing values, the influence of the uncertainty of missing data of mine ventilation parameters on the analysis process is reasonably considered, and the missing data is filled in the prediction task of random forest in combination with the prediction mean matching model. Taking the Luxin No.2 Mine as an experimental example, the intelligent mine ventilation simulation system IMVS was used to preprocess the original data set of ventilation parameters of the Luxin No.2 Mine to obtain a complete and accurate complete dataset of mine ventilation parameters. Comparative experiments with different missing attributes, different data missing rates, and different number of iterations were conducted separately for the complete data set. The effectiveness of the model was evaluated by a variety of model evaluation indicators. The results show that the complete data set formed by the multiple imputation method of random forest-chained equation has good similarity with the original data set. Results of filling experiments with different missing columns show that the filling model can easily handle mixed data types, autonomously learning the correlations between parameters and thus reducing filling complexity. The n datasets formed after iterations are combined into a final dataset by analysis, which improves the filling accuracy. Experiments with different iterations on the complete data set after initial filling show that the data correlation will converge after a certain number of iterations.

During pumped energy storage using abandoned mines, coal pillars are not only affected by monotonic loads, but also suffer from frequent stress disturbances. The strength and deformation characteristics as well as the failure mode of the coal specimens under the influence of monotonic loading (stress path 1), multilevel constant-amplitude cyclic loading (stress path 2) and multilevel increasing cyclic loading (stress path 3) were studied using the coal samples from Hepan Coal Mine, Shaanxi Province, as the research object. The test results showed that the stress-strain curves of the coal specimens under cyclic loading formed obvious hysteresis loops, and the area of hysteresis loops increased significantly with the rise of stress level; compared with the axial strain, the circumstantial strain was more sensitive to the stress path; the peak strength and peak axial strain of the coal samples were the largest under monotonic loading, and the peak strength and axial strain of the specimens decreased by 22.12% and 18.35% (path 2) and 5.30% and 10.34% (path 3) under multi-level cyclic loading, respectively; the tangent modulus of the specimens under stress path 2 was significantly higher than the other stress paths; the stress paths had not changed the macroscopic failure mode of the coal specimens, but the cyclic loading caused the number and size of cracks on the specimen’s surface to become larger.

Objective To achieve supervision and management of the whole business process of blood center, raise productivity and ensure blood quality by enabling blood center managers comprehensively grasp the key business operation situation of the whole process at anytime and anywhere. Methods A whole business process supervision and management system was established covering background of preparation, business scope, content of position supervision and management, overall framework design, interface design of management and supervision management, physical database design, program development and online debugging, and was integrated with the blood bank management information system. The display and management were through a mobile APP to record key indicators of business process from blood collection to blood supply timely and comprehensively. Statistical analysis was conducted on total collection volume, total preparation volume and total supply volume, as well as discarding rate of test unqualified and of non-test unqualified (lipemic blood excluded) in 2023 and 2022. Results We established a mobile APP based on a blood bank management information system for business supervision and management of whole process, and achieved management by phones. After its implementation in 2023, the total collection volume, total preparation volume and total supply volume in 2023 were all higher than those in 2022, with growth rates of 5.88% (13 247/225 454 U), 4.73% (24 156/510 698 U), and 6.70% (34 814/519 914 U), respectively. The discarding rate in 2023 was lower than that in 2022 (0.54%, 2 868/534 854 U) vs (0.60%, 3 047/510 698 U) (P

This is an article in the field of process mineralogy. Systematic process mineralogy study on phosphorus tailings was carried out by using the advanced mineral identification and characterization system (AMICS). The chemical compositions, mineral components, embedded characteristics of minerals, particle size, and the characteristics of liberation degree and the other characteristics were mainly studied. The results show that the gangue minerals are mainly dolomite and quartz. The phosphate mineral is mainly collophane which exists in the form of poor intergrowth. The phosphate mineral is extremely finely disseminated and closely associated with the gangue minerals. This study can provide some guidance for the optimization of phosphate ore dressing and the comprehensive utilization of tailings resources.

To solve the problem that the law of rock electrical response under low and medium water saturation in tight sandstone reservoirs is not clear, an experimental method of high-speed centrifugal displacement rock electricity and nuclear magnetic resonance T2 spectrometry under different water saturation was proposed, which can drive the tight sandstone cores with the permeability less than 0.1×10−3 μm2, and provide a reliable experimental means for the study of tight sandstone electrical property. By carrying out supporting experiments such as high-resolution CT scan, MAPS and Qemscan, a multi-mineral component fine three-dimensional digital core based on multi-source information fusion was constructed. The finite element numerical simulation method was used to obtain the electrical response of tight sandstone core with low water saturation which cannot be obtained in laboratory conditions. By combining experiment and numerical simulation, the electrical response laws have been clear of tight sandstone with complex pore structure, and the saturation evaluation method of variable rock electrical parameters based on pore structure has been developed. The processing of logging data of multiple wells in tight sandstone reservoir of Chang 7 Member in the Ordos Basin shows that this method can obtain more accurate oil saturation, and provides a new idea and method for fine logging evaluation of tight sandstone reservoir. Key words: tight sandstone, rock electrical response, nuclear magnetic resonance logging, saturation, petrophysics, numerical simulation

The traditional method of joint calibration of fixed baseline interferometer with multiple errors requires more than three calibration emitters to achieve real-time calibration of the interferometer in orbit, but the performance of the traditional method will be reduced or even failed when the number of calibration emitters is insufficient. For the situation that the number of calibration emitters is insufficient, a single or double emitters calibration method for fixed baseline interferometer is proposed. Under the condition of relative motion between the interferometer and the calibration emitters, a set of phase differences of calibration signals is obtained firstly by multiple measurements, and a set of equations about the systematic errors of the interferometer is listed by using the obtained phase differences, finally the systematic errors are solved by the Penrose inverse matrix assisted iterative least squares method. The simulation results verify the feasibility of the proposed method. On this basis, the influence of the emitter selection on the positioning performance of the interferometer after calibration is analyzed qualitatively by means of numerical simulation, decomposing the parameters of the emitter selection. The analysis results show that the calibration emitter located near the sub-star in the single emitter case or two calibration emitters located far apart both can make the interferometer obtain better positioning performance after calibration.

A gas chromatography-mass spectrometry (GC-MS) with selected ion monitoring (SIM) method for the precise quantitative and qualitative analysis of 58 volatile components in grape fruits of different varieties using stable isotope labeled internal standard was developed based on the understanding of the mass spectrometric cleavage behavior of special volatile components. The difference in the volatile composition of the tested varieties was explored. After crushing and homogenization, grape samples were extracted by solid phase microextraction (SPME) and analyzed by GC-MS-SIM. The results indicated that this method had good linear relationships within the investigated concentration range with a correlation coefficient (R) greater than 0.995 0 for all analytes expect for isopropanol (equal to 0.967 1). The limits of detection (LODs) for most target compounds were lower than 1.56 μg/kg. The spiked recoveries of only a few volatile components were very low, while those of most volatile components ranged from 60.64% to 129.63% with relative standard deviations (RSDs) less than 19.56%. This method was suitable for qualitative and quantitative analysis of volatile components in grape and other fruits as well as vegetables, with high sensitivity and accuracy. Furthermore, the characteristic volatile components of 12 grape varieties were identified by analyzing the differences in their volatile composition.