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Effects of herbicide butachlor application on the growth of periphytic biofilms and nitrogen loss in paddy systems

Pedosphere 2024年第1期34卷 211-221页

作者： Yanhui ZHAO Mingjun LEI Liandong JING Fan XIA Meixia YAN jiantong liu Yonghong WU Yunli WU Chenxi WU Ecology and Environment Monitoring and Scientific Research Center Yangtze Basin Ecology and Environment AdministrationMinistry of Ecological and EnvironmentWuhan 430010China College of Chemistry and Environmental Protection Engineering Southwest Minzu UniversityChengdu 610041China State Key Laboratory of Freshwater Ecology and Biotechnology Institute of HydrobiologyChinese Academy of SciencesWuhan 430072China State Key Laboratory of Soil and Sustainable Agriculture Institute of Soil SciencesChinese Academy of SciencesNanjing 210008China

The application of butachlor as an herbicide in paddy fields is widely practiced,aiming to increase rice yield by directly or indirectly influencing the paddy *** biofilms,which form at the soil-water interface in paddy fields,are complex bioaggregates that play an important role in nitrogen (N) *** objective of this study was to investigate the effect of butachlor on periphytic biofilm growth and N cycling under both light and dark conditions in the *** results revealed that butachlor application hindered the growth of periphytic biofilms and led to the dominance of Cyanobacteria as the primary prokaryotes,while inhibiting the development of eukaryotic ***,the application of butachlor reduced the richness and diversity of prokaryotes,but increased those of eukaryotes in periphytic *** light treatments exhibited higher total N loss because light favored periphytic biofilm growth and enhanced ammonium (NH_(4)^(+)) assimilation and ***,butachlor application resulted in the increased retention of NH_(4)^(+)-N and nitrate (NO_(3)^(-))-N and an increase in N loss via *** abundances of functional genes encoding enzymes such as ammonia monooxygenase,nitrite reductase,and nitrous oxide reductase were increased by butachlor application,favoring nitrification and denitrification ***,the results suggest that butachlor application leads to an increase in total N loss mainly through denitrification in paddy systems,particularly in the presence of periphytic ***,the results may provide valuable insights into the changes in periphytic biofilm growth and N cycling induced by butachlor,and future studies can further explore the potential implications of these changes in paddy soils.

关键词： ammonia-oxidizing bacteria amoA denitrification denitrifying bacteria nirK nitrification nitrogen cycling nosZ volatilization

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数控加工中激光探头光轴垂直度误差标定方法

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激光杂志 2024年第3期45卷 243-247页

作者：刘建通黄景德冯悦珠海科技学院广东珠海519041

在数控加工中,由于无法精准地获取激光探头光轴垂直度误差,因此,为了解决这一问题,提出数控加工中激光探头光轴垂直度误差标定方法。通过构建数学模型,确定激光探头光轴的基准平面,并对激光探头光轴的理想垂直度展开计算。对激光探头光... 详细信息

在数控加工中,由于无法精准地获取激光探头光轴垂直度误差,因此,为了解决这一问题,提出数控加工中激光探头光轴垂直度误差标定方法。通过构建数学模型,确定激光探头光轴的基准平面,并对激光探头光轴的理想垂直度展开计算。对激光探头光轴图像实施二值化去噪操作,并对其展开边界扩展处理。通过Harris算子提取激光探头光轴垂直度特征信息,调整光轴与物面的垂直度,实现激光探头光轴垂直度误差标定。实验结果表明,所提方法对激光探头光轴垂直度误差标定精准度高,误差值保持在-0.5 mm~0.5 mm,表明所提方法的性能好。

关键词：数控加工误差标定 Harris算子二值化去噪激光探头光轴垂直度

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深入学习领会党的十九届六中全会精神全力推进现代职业教育高质量发展

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中国职业技术教育 2022年第1期38卷 5-11页

作者：刘建同中国职业技术教育学会北京100029

深入学习领会党的十九届六中全会精神,职业教育必须立足新发展阶段、贯彻新发展理念、融入新发展格局,瞄准科技变革和产业优化升级,努力增强适应性并实现高质量发展,以更好契合人民群众之期望,培养更多高素质技术技能人才、能工巧匠、... 详细信息

深入学习领会党的十九届六中全会精神,职业教育必须立足新发展阶段、贯彻新发展理念、融入新发展格局,瞄准科技变革和产业优化升级,努力增强适应性并实现高质量发展,以更好契合人民群众之期望,培养更多高素质技术技能人才、能工巧匠、大国工匠,为实现第二个百年奋斗目标和中华民族伟大复兴的中国梦提供有力的人才和技能支撑。

关键词：高质量发展强国建设知识技术技能

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Experimental of the influence of mineral composition and normal stress on the frictional slip of shale

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Earthquake Research Advances 2021年第2期1卷 40-48页

作者： Xiaodi Li Jianbo Wang Wei Zhou jiantong liu Li Qu Petroleum Institute China University of Petroleum-Beijing at KaramayKaramay 834000China Research Institute of Experiment and Detection of Xinjiang Oilfield Company Karamay 834000China Unconventional oil and Gas Technology Research Institute China University of PetroleumBeijing 102249China Kela Oil and Gas Development Department of PetroChina Tarim Oilfield Company Korla 841000China

Natural fractures are widely distributed in shale *** the hydraulic fracturing process,frictional slip occurring on natural fractures can increase the reservoir permeability and is of great significance to improve the efficiency of reservoir *** contains a large amount of clay and organic matter,and its frictional behavior is different from that of other previously studied *** this paper,the frictional behavior of shale is analyzed,and the results show that the frictional behavior is controlled by the content of clay and organic *** the content of clay and organic matter increases,the micro support type transforms from the particle support mode by hard quartz mineral to matrix support mode by plastic clay and organic ***,the shear strength and friction coefficient of shale both decrease,and the shear type transforms from brittle to *** the content of clay and organic matter is low,the asperity of friction surfaces will break in a brittle manner and the wear degree of surfaces is ***,fractures are still featured by moderate apertures after *** lower the content of clay and organic matter is,the easier the asperity of crack surfaces supports themselves,and the higher the fracture residual permeability ***,promoting shear slip is the main measure of reservoir ***,when the content of clay and organic matter is high,the remaining post-slip fracture aperture is *** is difficult to increase reservoir permeability through the frictional slip of natural fractures,and in this situation,the proppant support efficiency needs to be improved.

关键词： Shale Mineral composition Frictional slip Friction coefficient Roughness

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Effects of inorganic arsenic on growth and microcystin production of a Microcystis strain isolated from an algal bloom in Dianchi Lake,China

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Chinese Science Bulletin 2011年第22期56卷 2337-2342页

作者： GONG Yan AO HongYi liu BiBo WEN Sheng WANG Zhi HU DingJing ZHANG XingZhong SONG LiRong liu jiantong Institute of Agricultural Quality Standards & Testing Technology Hubei Academy of Agriculture Sciences Wuhan 430064 China Institute of Hydrobiology Chinese Academy of Sciences Wuhan 430072 China Department of Resourses and Environment Engineering Henan Institute of Engineering Zhengzhou 451191 China National Institute of Nutrition and Food Safety Chinese Center for Disease Control and Prevention Beifing 100050 China Institute of Agricultural Resource and Environmental Sciences Jiangsu Academy of Agricultural Sciences Nanjing 210014 China

Our previous data have shown that inorganic arsenic concentrations were high in Dianchi Lake,China,where Microcystis blooms often *** explore the relationship between arsenic and the growth of Microcystis,the effects of arsenite[As(III)]and arsenate[As(V)]on the growth and toxin production of *** strain FACHB 905 were *** showed that *** FACHB 905 was tolerant to inorganic arsenic and its growth was not inhibited when the concentration of As(III)was below 10-5 mol L-1 or that of As(V)below 10-3 mol *** microcystin production was stimulated in the presence of 10-7 mol L-1 As(III)and the response of this *** strain to As(III)seemed to be a typical inverted U-shaped *** content increase of microcystin-LR per cell indicated that the toxicity was enhanced as *** FACHB 905 was exposed to As(V).Considering the relatively high concentration of inorganic arsenic in Dianchi Lake(139μg L-1 in epilimnetic water),the origin of the *** strain,inorganic arsenic favors survival of *** FACHB 905 and may stimulate its microcystin production and cellular toxicity.

关键词：微囊藻毒素无机砷生产滇池中国假单胞菌分离藻华

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A graph deep learning method for landslide displacement prediction based on global navigation satellite system positioning

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Geoscience Frontiers 2024年第1期15卷 29-38页

作者： Chuan Yang Yue Yin jiantong Zhang Penghui Ding Jian liu China Transport Telecommunications and Information Center Beijing 100011PR China China Nuclear Power Engineering Co. LtdBeijing 100011PR China

The accurate prediction of displacement is crucial for landslide deformation monitoring and early *** study focuses on a landslide in Wenzhou Belt Highway and proposes a novel multivariate landslide displacement prediction method that relies on graph deep learning and Global Navigation Satellite System(GNSS)*** model the graph structure of the monitoring system based on the engineering positions of the GNSS monitoring points and build the adjacent matrix of graph *** construct the historical and predicted time series feature matrixes using the processed temporal data including GNSS displacement,rainfall,groundwater table and soil moisture content and the graph *** introduce the state-of-the-art graph deep learning GTS(Graph for Time Series)model to improve the accuracy and reliability of landslide displacement prediction which utilizes the temporal-spatial dependency of the monitoring *** approach outperforms previous studies that only learned temporal features from a single monitoring point and maximally weighs the prediction performance and the priori graph of the monitoring *** proposed method performs better than SVM,XGBoost,LSTM and DCRNN models in terms of RMSE(1.35 mm),MAE(1.14 mm)and MAPE(0.25)evaluation metrics,which is provided to be effective in future landslide failure early warning.

关键词： Landslide displacement prediction GNSS positioning Graph deep learning

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Frequency Regulation of VSC-MTDC System with Offshore Wind Farms

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Journal of Modern Power Systems and Clean Energy 2024年第1期12卷 275-286页

作者： Haoyu liu Chongru liu North China Electric Power University Beijing 102206China

Frequency regulation of voltage source converter-based multi-terminal high-voltage direct current(VSC-MTDC)system with offshore wind farms enhances the frequency stability by compensating the power for a disturbed AC ***,it is difficult to reasonably allocate frequency-regulation resources due to a lack of coordination mechanisms between wind farms and the MTDC ***,it is difficult for the frequency control of the wind farms to manage changes in wind speed;and the risk of wind-turbine stalls is ***,based on the kinetic energy of wind turbines and the power margin of the converters,the frequency-regulation capability of wind turbines is evaluated,and a dynamic frequency-support scheme considering the real-time frequency-support capability of the wind turbines and system frequency evolution is proposed to improve the frequency-support performance.A power adaptation technique at variable wind speeds is developed;the active power in the frequency-support stage and restoration stage is switched according to the wind speed.A hierarchical zoning frequency-regulation scheme is designed to use the frequency-regulation resources of different links in the MTDC system with wind *** simulation results show that the novel frequency-regulation strategy maintains frequency stability with wind-speed changes and avoids multiple frequency dips.

关键词： Wind generation voltage source converter-based multi-terminal high-voltage direct current(VSC-MTDC) frequency regulation cooperative control adaptive control variable wind speed

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A Novel Design of a Pre-separation Panel Structure to Protect Against the Impact of an Explosion in an Aircraft Plenum Chamber

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Acta Mechanica Solida Sinica 2024年第1期37卷 166-180页

作者： Zongxing liu Xiang Yang Jun liu School of Aeronautics Northwestern Polytechnical UniversityXi'an 710072China COMAC Shanghai Aircraft Design and Research Institute Shanghai 201210China

To reduce the damage of the pressurizing panel structure of a fuselage caused by an explosion at the“least risk bomb location”in an aircraft structure,a new pre-separation panel structure was designed to resist blast ***,the dynamic strain response and morphology of impact damage of the new pre-separation panel were measured in an impact damage ***,the commercial software LS-DYNA was used to calculate the propagation of the blast shock wave,and the results were compared with empirical equations to verify the rationality of the numerical calculation ***,the fluid–structure coupling method was used to calculate the damage process of the pre-separation panel structure under the impact of an explosion wave and an impact *** calculated results were in good agreement with the test results,which showed the rationality of the calculation method and the *** residual strength of the damaged pre-separation panel was significantly higher than that of the original damaged *** results show that the new pre-separation panel structure is reasonable and has certain significance for guiding the design of plenum chambers with strong resistance to implosion for aircraft fuselages.

关键词： Pre-separation panel structure Explosive response Residual strength Aircraft plenum chamber Least risk bomb location

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Effectiveness and safety of acupuncture in treatment of pregnancyrelated symptoms:a systematic review and Meta-analysis

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Journal of Traditional Chinese Medicine 2024年第1期44卷 16-26页

作者： liu Tingting liu Tongou liu Mingfu School of Traditional Chinese Medicine Clinical Medicine Hubei University of Traditional Chinese MedicineWuhan 430000China First Clinical College of Hubei University of Traditional Chinese Medicine Wuhan 430000China Department of Acupuncture and Tuina Affiliated Hospital of Hubei University of Traditional Chinese MedicineHubei Provincial Hospital of Traditional Chinese MedicineWuhan 430000China

OBJECTIVE:To systematically evaluate the efficacy and safety of acupuncture(AM)in the treatment of pregnancyrelated symptoms such as acute vomiting during ***:We comprehensively searched the available literature up to November 2021,including Pub Med,Embase,Cochrane Library,Chinese Biomedical Literature Database,and China National Knowledge Infrastructure Database,for randomized controlled trials(RCTs)on AM for the treatment of severe vomiting,insomnia,pharyngeal and pelvic pain,mood abnormalities,and dyspepsia during ***:Sixteen RCTs with a cumulative sample size of 1178 cases were *** these,964 patients were included in the *** Meta-analysis results showed that AM was more efficient than Western medicine in treating discomfort during pregnancy[odds ratio(OR)=1.19,95%confidence interval(CI)(1.11,1.28),P<0.01].AM was better than the control group in improving the visual analog scale scores[standard mean difference(SMD)=0.62,95%CI(0.53,0.71),P<0.01].AM was superior to the control group in improving Numerical Rating Scale(NRS)symptom scores[OR=7.31,95%CI(3.36,15.94),P<0.01].There was no significant difference in adverse effects between the AM and sham-AM groups and the analgesic drug group[OR=0.70,95%CI(0.39,1.28),P=0.25],but the treatment and control groups had mild adverse effects with a low ***:AM is more effective than other treatments or pharmacotherapy alone in the treatment of pregnancy-related symptoms,and is relatively ***,the quality of the included trials was rather poor,and high-quality studies are required to confirm our findings.

关键词： acupuncture pregnancy nausea vomiting sleep initiation and maintenance disorders low back pain pelvic pain mood abnormalities Meta-analysis systematic review

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Stochastic Unit Commitment with High-Penetration Offshore Wind Power Generation in Typhoon Scenarios

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Journal of Modern Power Systems and Clean Energy 2024年第2期12卷 535-546页

作者： Yanqi liu Dundun liu Hongcai Zhang State Key Laboratory of Internet of Things for Smart City and Department of Electrical and Computer Engineering University of MacaoMacao 999078China University of Macao Zhuhai UM Science and Technology Research Institute ZhuhaiChina

To tackle the energy crisis and climate change,wind farms are being heavily invested in across the *** China's coastal areas,there are abundant wind resources and numerous offshore wind farms are being *** secure operation of these wind farms may suffer from typhoons,and researchers have studied power system operation and resilience enhancement in typhoon ***,the intricate movement of a typhoon makes it challenging to evaluate its spatial-temporal *** published papers only consider predefined typhoon trajectories neglecting *** address this challenge,this study proposes a stochastic unit commitment model that incorporates high-penetration offshore wind power generation in typhoon *** adopts a data-driven method to describe the uncertainties of typhoon trajectories and considers the realistic anti-typhoon mode in offshore wind farms.A two-stage stochastic unit commitment model is designed to enhance power system resilience in typhoon *** formulate the model into a mixed-integer linear programming problem and then solve it based on the computationally-efficient progressive hedging algorithm(PHA).Finally,numerical experiments validate the effectiveness of the proposed method.

关键词： Unit commitment two-stage stochastic programming offshore wind farm typhoon

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