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Copyright of Coal Science & Technology (0253-2336) is the property of Coal Science & Technology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Progress in Modern Biomedicine is the property of Publishing House of Progress in Modern Biomedicine and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Progress in Modern Biomedicine is the property of Publishing House of Progress in Modern Biomedicine and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

目的探索RhD阴性孕妇围生期输血管理模式，确保孕妇输血安全。方法选取2014年8月至2015年 12月该院产科收治的住院并分娩孕妇8 092例，其中RhD阴性孕妇49例作为研究对象，为RhD阴性孕妇建立信息档 案，在孕妇预产期前1个月预约RhD阴性血液，入院待产后为孕妇备好同型血液。分娩过程中或产后对有输血申请者给予 科学、合理的用血指导。结果49例RhD阴性孕妇预约RhD阴性血液率为100.0%，采供血机构实际供给率为905%(38/42)。 孕妇剖宫产手术或顺产均安全实施，且没有造成血液浪费及耽误临床用血。仅1例急诊手术大量出血孕妇输注ABO同 型RhD阴性血液2 U，紧急情况下输注配血相合的ABO同型RhD阳性血液4 U。择期手术2例孕妇按备血量输注。 结论实行RhD阴性孕妇孕期管理、术前供血管理、手术输血管理既保证了临床安全用血，并可有效节约和保护稀有血 液资源。 [ABSTRACT FROM AUTHOR]

目的探讨低离子强度盐溶液微柱凝集法交叉配血实验的应用及影响因素。方法利用生理盐水、低离子溶液分别对2189例受血者和2189例供血者进行凝集配血试验。用低离子强度盐溶液配制红细胞进行交叉配血阳性54例（2.5%），阴性2135例（97.5%）；用生理盐水阳性32例（1.1%），阴性2167例（98.9%），对每组结果进行统计学处理。结果2种介质在红细胞悬液交叉配血的结果比较，差异有统计学意义（P<0.05）。结论低离子强度盐溶液用于微柱凝集法交叉配血实验的敏感性增高，特异性增强，结果稳定，适于临床输血前交叉配血实验的血清学检测。 [ABSTRACT FROM AUTHOR]

The electronic structure and optical properties of intrinsic Mn4Si7 and Mn4Si7 doped with different Al concentrations were calculated by the first - principles calculation method based on the framework of density functional theory. There are 16 Mn atoms and 28 Si atoms in Mn4Si7 unit cell, four doping models of Mn16 xAlx Si28 ( x = 0, 2, 4, 8) were established. The calculation results show that undoped Mn4Si7 is an indirect band gap semiconductor and its band gap width is 0. 775 eV. The doping of Al causes the electronic structure near the Fermi energy level of Mn4Si7 to change, the conduction band shifts to the low - energy direction, the valence band shifts to the high - energy direction, and the band gap becomes zero, showing metallicity. In addition, Al - doped Mn4Si7 increases the dielectric function, refractive index, absorption and reflection coefficient and other properties in the low energy region of photon energy, improved the photoelectric properties of Mn4Si7 in the infrared region. [ABSTRACT FROM AUTHOR]

YbBaCo4O7+δ oxygen adsorption material doped with different concentrations of Sm was prepared by sol-gel method. The structure, morphology and oxygen adsorption/desorption properties of the Yb1-xSmxBaCo4O7+δ nanopowder were analyzed by XRD, SEM and differential thermal analyzer. The effects of different concentrations of Sm doping on YbBaCo4O7+δ nanopowder were studied. The test results show that the rare earth element Sm completely enters the lattice of Yb1-xSmxBaCo4O7+δ nanopowder. And Yb1-xSmxBaCo4O7+δ nanopowder is still a single 114 phase structure. Sm doping has little effect on the morphology of Yb1-xSmxBaCo4O7+δ nanopowder. A certain amount of rare earth element Sm doping can significantly improve YbBaCo4O7+δ. For the oxygen adsorption performance of Yb1-xSmxBaCo4O7+δ nanopowder, the change of oxygen adsorption of YbBaCo4O7+δ is 1.7%, while the change of oxygen adsorption of Yb0.8Sm0.2BaCo4O7+δ is 4.6%. And Yb1-xSmxBaCo4O7+δ has good circulation performance. The improvement of its oxygen adsorption/desorption performance is due to the improvement of oxygen storage space in Yb1-xSmxBaCo4O7+δ by rare earth element Sm doping. [ABSTRACT FROM AUTHOR]

Rare earth Y doped PrBaCo2O5+δ thermoelectric ceramics were prepared by traditional ceramic. The effects of rare earth Y doping on the crystal structure and thermoelectric properties of PrBaCo2O5+δ oxide thermoelectric ceramics were studied by XRD and thermoelectric performance testing system. The test results show that Pr1-xYxBaCo2O5+δ thermoelectric ceramics are double-layer perovskite structure. Within the test temperature range, the Seebeck coefficients of Pr1-xYxBaCo2O5+δ（x=0, 0.25, 0.5, 0.75） thermoelectric ceramics are positive, indicating that the conductive carrier of the thermoelectric ceramics is a hole, which is a p-type semiconductor. Rare earth Y doping can significantly improve the conductivity of Pr1-xYxBaCo2O5+δ thermoelectric ceramics. On the contrary, the Seebeck coefficient of Pr1-xYxBaCo2O5+δ thermoelectric ceramics decreases. Pr0.5Y0.5BaCo2O5+δ thermoelectric ceramics have a maximum power factor of 79.4 μW/（m·K²） at 1 073 K. [ABSTRACT FROM AUTHOR]

4D printing technology is a variable characteristics rapid prototyping technology, which is mainly based on 3D printing. It additively manufactures the desired object with intelligent materials. The molding firmware can be stimulated by the external environment, in terms of its shape, structure or function of the time dimension changes. Since the technology was proposed, it has attracted the attention of a large number of scholars. With the continuous deepening of research on 4D printing technology, this technology plays a significant advantage in the interdisciplinary integration. This paper first reviews the research status of shape memory intelligent materials in 4D printing, and then elaborates the application research of 4D printing technology based on shape memory intelligent materials in the fields of medical, bionic, military and life product manufacturing. Finally it looks forward to the potential applications and challenges of 4D printing shape memory intelligent materials in the future development. [ABSTRACT FROM AUTHOR]

Reservoir sediment deposition is an important factor that causes the reduction of effective storage capacity, the increase of operation cost and the shortening of reservoir life. Scientific discrimination of reservoir sediment deposition situation and reasonable sediment discharge measures are effective ways to solve reservoir sediment deposition. Since the Wenchuan earthquake, the amount of sediment entering into the Zipingpu Reservoir has been increased, posing a great threat to the safe operation of the reservoir and the safety of downstream water use. The results of the study show that before the Wenchuan earthquake, the runoff in the upper reaches of the Minjiang River is decreased, and after the earthquake, there is a little recovery, but it is still at the level of dry years. After the earthquake, the amount of sediment entering into the reservoir has been increased significantly. The total amount of sedimentation in the reservoir is 195.2 million m³, accounting for 17.55% of the total reservoir capacity. The sediment is generally deposited in the middle of the reservoir area, and the sedimentation in front of the dam is relatively small. In order to deal with the issue of reservoir sedimentation, the prevention and control measures of reservoir sedimentation to reduce sediment from the upstream, sediment discharge by density current, artificial dredging, and the comprehensive sedimentation reduction method of “sediment regulation in the upper reservoir and water regulation in the lower reservoir” combined with engineering measures and non engineering measures are proposed to provide decision-making suggestions for the healthy and long-term operation of Zipingpu Reservoir. [ABSTRACT FROM AUTHOR]

During the autumn flood season of 2021, rainstorms occurred frequently in the main and tributaries of the Yellow River, and three numbered floods followed, with rare flood history. This paper summarized the characteristics of this autumn flood from the aspects of rainfall, water, flood and reservoir operation and lists historical autumn floods for comparison. Around the three numbered floods of the Yellow River, through the changes of inflow and outflow and water level of Sanmenxia, Xiaolangdi, Luhun, Guxian and Hekoucun reservoirs in the regulating process, it was calculated that the peak clipping of the "five-reservoir joint regulation" in the three floods was 49.29%, 46.10% and 47.84% respectively. The flood detention effect was Xiaolangdi > Sanmenxia > Guxian > Luhun > Hekoucun. Through the analysis, it is concluded that the local river flat flow in the lower reaches of the Yellow River is less than 5,000 m³/s, which is the most critical factor restricting reservoir operation and downstream flood control safety. Suggestions are put forward to improve the flood capacity of the lower reaches of the river at the bayou section so as to open the operation space of cascade reservoirs. [ABSTRACT FROM AUTHOR]

In order to achieve the accurate sediment composition estimation of out reservoir in Xiaolangdi Reservoir, the estimation models for each sediment composition of out reservoir that comprehensively considering various influencing factors were established, using three different machine learning algorithms including XGBoost, KNN and GPR and based on the series data of water and sediment during the period of wa-ter-sediment regulation from 2002 to 2019. The analysis results show that it is effective to apply machine learning algorithms to estimate the sediment composition of out reservoir, and there is the good correlation between the estimated and actual value of each model. In comparison, for different sediment compositions of out reservoir, the coefficient of determination R2 of the estimation model using KNN algorithm is the highest, and the average absolute error EMAE and root mean square error ERmsEof it are all the smallest, which shows that the KNN algorithm model has higher accuracy and precision on the sediment composition estimation of out reservoir. [ABSTRACT FROM AUTHOR]

The accurate prediction of groundwater level has great significance to the management of groundwater. A prediction model based on multivariate long short-term memory (LSTM) neural network was constructed by taking the precipitation representing the recharge term and the temperature, vapor pressure and groundwater extraction representing the discharge term. The model used monthly precipitation, tempera-ture, vapor pressure, groundwater extraction, groundwater levels of quaternary and karst aquifer data from 2010 to 2018 of Jinan City as training set while used monthly data of 2019 as validation set. The results show that: a) using sine function signal to fit temperature data can eliminate the influence of temperature measurement errors and improve model prediction accuracy; b) the optimal prediction results can be obtained when the neuron dropout rate is 20%; the prediction Root-Mean-Square Error(RMSE) of quaternary groundwater level is 0.84 m, and the prediction Root-Mean-Square Error( RMSE) of karst groundwater level is 0.68 m; c) in general, the LSTM model can accurately simulate the dynamic characteristics of groundwater levels, and the predicting error is relatively larger only when the groundwater level is dra-matically changed. [ABSTRACT FROM AUTHOR]

The non-targeted metabolomics technology of ultra-high performance liquid chromatography tandem quadrupole time-of-flight mass spectrometer（UPLC-QTOF-MS） was used to construct a discrimination model between normal navel oranges and those with Huanglongbing disease, with the metabolites difference between those two navel oranges being investigated. It mainly used a combination of unsupervised（PCA） and supervised（OPLS-DA） models. Based on different criteria of VIP>1, P<0. 001, Fold change>2 or <0. 5, a total of 308 kinds（212 kinds in peers and 96 in pulp） of differential compounds were screened out, and 28 compounds of them（21 kinds in peer and 11 kinds in pulp） were identified. The main components were flavonoid glycosides and amino acid. The results showed that the content of amino acids and glycosides including naringin in the peel of navel oranges increased significantly, the content of glucose decreased, and the content of limonin in the pulp increased after the navel orange suffered from Huanglongbing. At the same time, the cluster analysis showed that the dynamic change trends of glycosides and naringin were the same, and the dynamic changes of abscisic acid, isosinensetin, glucose and amino acids were the same. This article explored the compositional changes of navel oranges after being infected with Huanglongbing It provided a new idea in the prevention or identification of diseased trees and also provided a new direction for the processing of diseased navel orange fruits. [ABSTRACT FROM AUTHOR]

The river regime evolution of wandering channel includes not only gradual process but also mutation process. The sudden change of river regime refers to the large adjustment of the local or overall river regime in a short period of time in a wandering channel. The sudden change of river situation has brought major challenges to river flood control, water supply security and river governance. If the sudden change of river situation is properly utilized in some cases, it can effectively improve the control ability of the river regulation project and enhance the stability of the river situation. This paper reviews the research progress from the practical significance, connotation and research methods of the abrupt adjustment of the river situation of the wandering channel, points out the shortcomings of the existing research, and puts forward the problems that need to be paid attention to in the future research on the river situation abrupt change. Carry out the research on the sudden change of the river situation of the wandering channel to point out the direction. [ABSTRACT FROM AUTHOR]

In order to grasp the regulation and utilization potential of key reservoirs in the Yellow River Basin, the value evaluation system of sediment dynamic regulation potential of key water conservancy projects was established based on the characteristic indexes of sediment control potential, sediment transport potential and sediment resource utilization potential combined with the common indexes of water conservancy projects. Sediment dynamic control capacity quantitative method was presented based on multi-objective grey target theory and the cumulative prospect theory. The method was used to deal with index matrix by the multi-objective grey target theory and realized the quantification of the potential value by combining with the cumulative prospect theory. Finally, taking the key reservoirs of the Yellow River as an example, the fuzzy assessment method was applied to make comprehensive evaluation of sediment dynamic control potential. The results show that the Xiaolangdi Reservoir has the highest sediment dynamic regulation capacity, Liujiaxia Reservoir, Sanmenxia Reservoir and Wanjiazhai Reservoir rank the second to the fourth respectively. [ABSTRACT FROM AUTHOR]

To study the vortex-induced vibration(VIV) of top tension risers(TTRs) under shear flow, the non-linear dynamic model of VIV for TTRs was constructed, in which the riser was simplified as an Euler-Bernoulli beam model and the van der Pol wake oscillator was used to describe the effect of fluid. Based on the 2 nd-order Galerkin modal discretization model, the harmonic balance method, the Poincaré mapping method and the Lyapunov exponential method were used to reveal the system response characteristics. The results show that periodic responses and quasi-periodic responses occur alternately with the increase of the flow velocity, and the periodic response region corresponds to the vortex-induced resonance region. The approximate periodic solution obtained with the harmonic balance method can predict the amplitude and frequency of the periodic solution in the vortex-induced resonance region, and the main frequency components of the quasi-periodic solution in the non-vortex-induced resonance region. [ABSTRACT FROM AUTHOR]

In order to scientifically and efficiently evaluate the operation status of transformers, reduce the probability of their faults and find potential defects, the disadvantages of the current state assessment methods for single transformer are expounded, and an algorithm for simultaneous state assessment of multiple transformers is proposed. The index system of transformer condition evaluation is established. The traditional TOPSIS method is improved by using grey correlation degree. The transformer condition evaluation model is established by using the improved algorithm. The state of six transformers is evaluated according to the relevant data. The evaluation results show that the improved transformer condition assessment method can evaluate and rank many transformers as a whole, reflecting the variation trend of each factor in each transformer and the difference between the ideal scheme, and verifying the rationality and effectiveness of the multi-transformer condition assessment method. [ABSTRACT FROM AUTHOR]