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In order to evaluate the high quality product rate of wheat in Shandong Province, and guide practice of grain circulation in production and consumption, the survey collected the wheat planting status and quality evaluation data in Shandong Province from 2017 to 2020, and analyzed them with the investigation method and quantitative analysis method. Results show that Shandong's wheat planting is stable and the total and per unit yields are increasing, as well as rate of high-quality wheat varieties. The evaluation of Shandong high-quality product evaluation demonstration area shows that since the start of “Good Grain and Oil of China” project, the rate of high-quality products has increased significantly. The study also discusses the wheat planting situation in Shandong and the existing issues, and proposes targeted solutions to improve the high quality product rate.

Since the national industrial standard LS/T 3109—2017 China good grain and oil - wheat was issued and implemented, there has been a new standard for rating high quality wheat. The main feature for this standard is to add variety consistency and food grading as the ranking indicator for high quality wheat. According to requirements of the standard, the quality indexes of newly harvested wheat samples in Shandong province were tested and analyzed including 81 samples from 2018 and 83 samples from 2019. The results showed that the compliance rate of new wheat varieties increased nearly 6 times and the high-quality rate increased nearly 8 times within two years. These data show that with the extension of the standard implementation time, its leading role in high-quality wheat planting has become increasingly prominent.

Based on the national standard GB 5009.4—2016, the relative contribution of each influencing factor to ash content change of wheat flour was studied, including sample weight, carbonization time, ashing time and ashing temperature. All the data were analyzed by Grubbs’test method. Ash content results indicated that the recommended weight for wheat flour is 3 g. Carbonization time and period were very important. The recommend means of ash temperature and ash time for wheat flour samples were 550 ℃ and 4 h, respectively.Means of ash content between dry basis and wet basis varied slightly. Finally, a measurement was proposed for wheat flour ash content based on the new standard of GB5009.4—2016.

For the sake of studying the catastrophe mechanism of stress-fissure coupling field in mining close distance seams in southwest China, a test working face in Guizhou province in southwest China is adopted and researched by the methods of numerical calculation and similar experiment. When the working face advances to 180 m in 4# coal seam in a similar experiment, the overlying rock breaks to the central base plate of Yulongshan limestone, and the conductive fractures run through the Changxing limestone karst cave and Yulongshan limestone karst cave. When the 1402 working face advances to 350 m, the top of vertical karst caves in the middle of the model produces extrusion damage, forming a penetrating water inrush passage. When the 1402 working face advances to 480 m, the top slab of the working face comes under periodic weighting with the short step. Besides, the mining of 9# coal seam starts after 4# coal seam in mining close distance seams. When the working face in 9# coal seam advances to 340 m in numerical simulation, the maximum opening of the overburden fractures is 51.16 mm. The fractures in the roof are mainly caused by the periodic breaking and falling of the basic roof, connected with the floor fractures of 4# coal seam. When the working face in 9# coal seam advances to 500 m, the maximum opening of the overburden fracture is 93.09 mm. Specifically, as the working face advances, the opening of fracture in the roof after collapse of the basic roof periodically is mainly greater than 5 mm, and the compaction closure is mainly 1 mm-5 mm. The fractures in the gob floor are mainly 0.1 mm-1 mm, and the fracture opening of the collapsed rock mass in the gob is mainly 1 mm-5 mm and greater than 5 mm. The karst caves in the overburden reduce the periodic weighting step of working face and play a guiding role in the direction of fracture development and water inflow passage formation. The karst caves are connected to surface waterfall holes and trap pits, and atmospheric precipitation recharges the water in the caves. The research results can be treated as an important basis for the prevention and treatment for water inrush disaster in mining close distance seams in the karst area of southwest China.

As the depth of coal mining in China increases, the dangerous break-up and the water inrush of the working face floor above aquiver show an increasing trend year by year. In this paper we investigate the working face floor of the Hedong Coalfield Shuangliu Coal Mine, and obtain the distribution characteristics of the aquifers under it by analyzing the hydrogeological data. We then employ a specially-designed working face floor water pressure simulation device to conduct simulation tests of the instability characteristics of the floor fracture during the mining process, and obtain the floor stress and displacement change laws for the working face. Finally, we employ the ‘plate model’ theory to calculate the maximum failure depth of the working face floor rock strata of the Shuangliu Mine. The results of the simulation test show that under the joint action of mining and aquifer water pressure, the floor failure regions are mainly concentrated in the coal walls and the area below the cut-holes, and the relief of the confined water pressure through mining can be simulated by using the new confined water simulation device.

Graphene-based metamaterial sensors are of significant research value for detecting food preservatives at low concentrations due to their extremely high sensitivity levels. In this work, we proposed and experimentally demonstrated an anapole resonance-based graphene metasurface (An-graphene-Ms) sensor with its conductivity altered by electrostatic doping effects for detecting and differentiating between two preservatives, sodium benzoate and potassium sorbate, in the terahertz region. Sodium benzoate, owing to its benzene ring structure, established π–π stacking interactions between the π-electrons in the benzene ring and those in graphene, amplifying the sensing effect. The amplitude changes and phase differences of the An-graphene-Ms sensor for the sodium benzoate detection were greater than those for potassium sorbate at the same concentration. Additionally, to reveal the dependence of the resonance frequency on the time delay, the measured signals were investigated using the continuous wavelet transform (CWT), and the time-frequency combination of the metasurface sensor was performed. The 2D wavelet coefficient intensity cards are effectively constructed through CWT, which also presents a more accurate approach for distinguishing and determining the concentrations of the two preservatives.

As one of the most important measurement equipment of the intelligent substation, digital electric energy meter fundamentally resolved the technical bottleneck of traditional substation. During the operation process, measurement accuracy and reliability are related to the safe and stable operation of power system. Based on the literatures related to the digital electric energy meter, this paper introduced the concept of digital meter, analyzed the error sources, and summarized its development status and the existing calibration method. The paper studied the calibration system based on IEC61850-9 and provided an accurate and safe application method for digital electric energy meter.

Background: It has been suggested that gestational diabetes mellitus (GDM) alters the growth trajectory of a fetus and increases the risk of abnormal birth weight. In spite of this, there is still a significant debate regarding the mode and optimal timing of diagnosing this condition. Our aim was to determine fetal growth velocity and birth biometry in pregnant women with GDM at varying risk levels. Methods: We conducted a cohort study involving 1023 pregnant women at a maternity hospital in Ma'anshan, China. All women completed an oral glucose tolerance test at 24–28 weeks' gestation. We measured fetal head circumference (HC), femoral length (FL), abdominal circumference (AC), biparietal diameter (BPD), and estimate fetal weight (EFW) by ultrasound at 17, 24, 31, and 35 weeks' gestation, respectively. Results: Overall, 5115 ultrasound scans were performed. Among both low-risk and medium–high-risk pregnant women at 17–24 weeks' gestation, GDM exposure was associated with an increase in fetal growth velocity. Neonates born to women with GDM at medium–high risk had significantly larger birth weights than those born to women without GDM, while this was not observed in women at low risk. Conclusion: In medium–high-risk pregnant women, exposure to GDM has a greater effect on the fetus, leading to abnormal fetal growth velocity that lasts beyond week 24. It is evident from our results that the effects of GDM on fetal growth differ between medium–high-risk pregnant women and low-risk pregnant women, and therefore a different screening program based on the risk factor for GDM is warranted. [ABSTRACT FROM AUTHOR]

Background: Knee osteoarthritis (KOA) has become a public health issue. Several systematic reviews (SRs) and meta-analyses (MAs) indicate that traditional Chinese exercise (TCE) may be an effective treatment for reducing pain and stiffness and improving physical function in people with knee osteoarthritis (KOA). Objectives: To evaluate the literature quality and evidence for the systematic reviews of TCE for KOA and provide evidence to support the clinical application of TCE for KOA. Methods: Eight databases were searched from their inception to January 3, 2023, to retrieve relevant literature, including China National Knowledge Infrastructure (CNKI), Wanfang, Chinese Scientific Journal Database (VIP), China Biology Medical literature database (CBM), PubMed, Embase, Web of Science and Cochrane Library, without restrictions on publication date or language. AMSTAR-2 and PRISMA 2020 assessed the methodological and reporting quality of included SRs/MAs. The Grading of Recommendations Assessment, Development, and Evaluation (GRADE) system was utilized to evaluate the quality of evidence. Results: A total of 18 SRs/MAs were included. The methodological quality was "very low" based on AMSTAR-2. The overall reporting quality was deficient based on PRISMA 2020. The quality of Chinese and English literature differed, with English literature being superior in methodological and reporting quality. Among 93 pieces of evidence obtained, 46 (49.46%) were of very low quality, 34 (36.56%) were of low quality, 13 (13.98%) were of moderate quality, and none were of high quality. TCE was supported by 76 pieces of evidence (81.72%). Conclusion: TCE appears beneficial and safe for managing KOA. However, due to the relatively low methodological and evidentiary quality of included SRs/MAs, clinicians should interpret these findings cautiously. [ABSTRACT FROM AUTHOR]