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semi-real time systems for subsidence monitoring in areas affected by underground mining:the example of the Nuraxi-Figus coal district(sardinia,Italy)

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International Journal of Coal science & Technology 2022年第6期9卷 112-126页

作者： L.Ammirati D.Di Martire F.Bordicchia D.Calcaterra G.Russo N.Mondillo Department of Earth sciences Environment and ResourcesUniversity of NaplesFedericoⅡ80126 NaplesItaly Department of Earth sciences Natural History MuseumLondon SW75BDUK sardinia region company carbosulcis s.p.a. 09010 GonnesaCIItaly

Underground mining can produce subsidence,which can be coincident with mining activities or delayed in response to the time-dependent deformation of the ***,in these cases,it is essential to effectively monitor the soil deformations at different times during and after mining *** the present work,an integrated approach based on geotechnical numeri-cal modeling and Advanced Differential Interferometric synthetic Aperture Radar(A-DInsAR)method has been applied to detect,study and monitor the subsidence related to mining activity in the Nuraxi Figus coal district(sardinia,Italy).Two datasets of high-resolution COsMO-skymed images were acquired,respectively in two covering periods:from 2011 and 2014,and from 2013 to ***-DInsAR results show that the predominant displacement rates are located in correspond-ence with the *** cumulated satellite-based Los displacements vary in the first period between-130 and+28 mm and-293 and+28.4 mm,while,during the second period between-6.9 and+1.6 mm and-8.72 and+4.33 mm in ascend-ing and descending geometries,*** geotechnical numerical model allowed to obtain a value for the maximum *** using the vertical and horizontal components it was possible to reconstruct the kinematics of the deformation considering three phases:pre-mining,syn-mining,and post-mining *** temporal evolution of displacements started during the mining extraction in 2011,achieved the major values in correspondence of post-mining operations,during the period from 2013 to 2014 and continued slowly until *** near real-time monitoring system applied in this study proved to be very useful for detecting subsidence during the mining activity and the post-mining period.

关键词： Mining monitoring A-DInsAR Numerical modeling subsidence Underground mining

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phosphorus fertilization alters complexity of paddy soil dissolved organic matter

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Journal of Integrative Agriculture 2020年第9期19卷 2301-2312页

作者： ZHANG Zhi-jian WANG Xian-zhe LIANG Lu-yi HUANG En TAO Xing-hua College of Environmental and Resource science Zhejiang UniversityHangzhou 310058P.R.China China Academy of West region Development Zhejiang UniversityHangzhou 310058P.R.China Hangzhou Gusheng Agricultural Technology company Limited Hangzhou 311108P.R.China

The structural complexity of soil dissolved organic matter(DOM)may reflect soil biogeochemical processes due to its spectral ***,the features of DOM structural complexity in paddy soil amended with long-term chemical p fertilization are still unclear,which may limit understanding of nutrient-related soil C *** collected soil samples from field experiments receiving application of 0,30,60,and 90 kg p ha–1 yr–1 to assess the effect of exogenous p on the complexity of soil DOM ***-dimensional excitation-emission matrix fluorescence analysis and enzymatic activity assay were used to determine the features of soil DOM molecular structure and the associated microbial *** results showed that p input increased the biodegradability of DOM,indicating by the increased lower molecular weight components and decreased humic degree in the DOM.p input also reduced the structural complexity of DOM with blue shifts of fluorescent *** fluorescence index andβ/αindex of DOM increased with increasing p application by 4–5%and 3–11%,respectively,while humification index decreased by 8–13%.The p input increased the abundance of bacteria and fungi by 34–167%and 159–964%,respectively,while 29–54%increments were found for theβ-1,4-glucosidase *** results implicated that p fertilization accelerated the soil DOM cycle,although the structural complexity of DOM declined,which potentially benefits soil C sequestration in paddy fields and may be a C sequestration mechanism in the p-dependent paddy.

关键词： soil carbon fertilization fluorescence humification agroecosystem

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Needling Neiguan(p6)for Treatment of Low pulse pressure syndrome—A Report of 31 Cases

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Journal of Traditional Chinese Medicine 2005年第4期25卷 273-275页

作者：李培润王辉高晶童安荣吴并生于良才毛树章 TCM Hospital of Ningxia Autonomous region Worker's Hospital of Yinchuan Zhongce(Great Wall)Rubber company Ltd. OpD of shenzhen Municipal Health school

Objective: To observe the impact of needling Neiguan (p 6) on the cardiovascular functional status in low pulse pressure syndrome. Method: 49 eligible patients were randomly assigned to a acupuncture group with bilateral Neiguan (p 6) needled for successive 3 days, and a medication group given a daily 20 mL of shenmai Injectio intravenously dripped for successive 6 days. The blood pressure, pulse pressure, stroke volume (sV), cardiac output(CO)/min, left ventricle work index (LVWI), mean arterial pressure (MAp), total peripheral resistance (TpR), coronary perfusion pressure (Cpp), pulmonary arterial wedge pressure (pAWp), effective blood volume (BV), blood viscosity (N), microcirculation half renewal rate (MHR), and cardiac muscle blood volume (CMBV) were determined before and after the treatment, which were compared with the parameters obtained in 23 healthy subjects. Results: The decreased pulse pressure of all patients before treatment (p＜0.01) increased significantly after treatment (p＜0.001). The levels of sV, CO, LVWI, pAWp, BV, MHR and CMBV were lowed when compared with the healthy subjects before treatment (p＜0.01), but all of them significantly increased after treatment (p＜0.01). The increased Cpp, TpR and N before treatment (p＜0.01) were decreased after treatment (p＜0.01). Conclusion: The therapeutic effect of acupuncture at point Neiguan (p 6) was better than medication though some of the indexes showed no significant difference (p＜0.05).

关键词：内关穴中医治疗针灸治疗低脉冲压综合症

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Rule of 100:An inherent limitation or performance measure in oxidative coupling of methane?

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Journal of Natural Gas Chemistry 2012年第3期21卷 308-313页

作者： saeed sahebdelfar Maryam Takht Ravanchi Mahtab Gharibi Marzieh Hamidzadeh Catalyst Research Group Petrochemical Research and Technology CompanyNational Petrochemical CompanyNo.27Sarv AlleyShirazi-southMollasadraP.O.Box ***TehranIran

The oxidative coupling of methane over La203/CaO type-catalyst in a fixed-bed reactor is studied under a wide range of operating conditions （973〈T〈 1103 K, 55〈 ptotal 〈220 kpa, and 3.7〈 mcat/VTp 〈50 kg.s/m^3）. A ten-step kinetic model incorporating all main products was used to predict the behavior of the system. Methane conversions and C2 selectivities were calculated by varying methane to oxygen ratios in the feed under different operating conditions which were also compared with the rule of 100. The results show that deviation from this rule depends on the operating conditions. Within the range studied, an increase in pressure, temperature and contact time results in smaller deviation from the rule. This rule is best approximated when the catalyst operates near its optimal performance. For negative deviations, common to the most catalysts, it is found that the optimal performance should occur at methane conversion levels lower than 50%. A plot of selectivity versus conversion for high-yield reported performance data of a large variety of catalysts shows that data points concentrated roughly in 20%-50% methane conversion region, confirming the generality and prediction of modeling.

关键词： oxidative coupling of methane (OCM) La203/CaO catalyst rule of 100 methane conversion C2 yield

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Nitrogen removal for low-carbon wastewater in reversed A^2/O process by regulation technology

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Journal of Central south University 2009年第S1期16卷 304-308页

作者：张智陈杰云谢丽华范功端尹晓静李勇 Key Laboratory of Three Gorges Reservior region's Eco-Enviroment Ministry of EducationChongqing University College of Architecture and Environment Sichuan University Jiguanshi Waste Water Treatment plant Chongqing Drainage Limited Company

Full scale experimental study on nitrogen removal for low-carbon wastewater was conducted in reversed A2/O process in Jiguanshi waste water treatment plant in Chongqing,in order to aid the operation and maintenance of similar WWTp. When the proposed measures,such as using 0.1% (volume fraction of wastewater) landfill leachate,shortening HRT by 2/3 in the primary sedimentation tank and controlling DO at 0.5 mg/L in the 3rd section of aerobic zone,are applied,15% of the carbon source can be complemented,the favorable property of activated sludge is achieved,and the nitrogen removal effect is significantly improved. The effluent NH3-N is 2 mg/L and the removal rate is 90%. The effluent TN is 17 mg/L and the removal rate is 54%. The up-to-standard discharge of the effluent is achieved. And after the optimization,the unit electricity consumption also reaches 0.21 kW/h and saves 20%.

关键词： reversed A2/O process low-carbon resource landfill leachate primary sedimentation tank nitrogen removal

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Experimental investigation on the anisotropy of friction property for dry and water-saturated rock

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Friction 2024年第9期12卷 2064-2082页

作者： Qing YANG Mingming HE Jinrui ZHAO Mingchen DING Jing WANG state Key Laboratory of Eco-hydraulics in Northwest Arid region Xi’an University of TechnologyXi’an 710048China China Communication Construction company Mechanical and Electrical Engineering Co. Ltd.Beijing 100088China

Friction properties of rock are closely connected with the *** anisotropy of rock friction can provide a valuable assessment for geotechnical and geological *** this study,the rotary friction tests were conducted to analyze the water effect on the friction property and the friction anisotropy of the four types of *** drilling response model(DD-model)was employed to characterize the rotary friction behavior of the *** parameters of this model include the three types of friction parameters:1/ς,μ,and f,where 1/ςandμare constant,and f is a variable.A quantitative method is proposed for assessing the anisotropy of rock *** results of the rotary friction tests indicate that the relation between torque force and thrust force conforms to the *** changes of two friction constants 1/ςandμfrom dry state to water-saturated state suggest that the water effect on the friction strength of the rocks exhibits significant *** friction strength determined by the friction variable f increases first,then decreases,and finally stabilizes with the increasing of *** is an anisotropy index calculated by the proposed *** percentage difference of the average value of AIf between water-saturated and dry states shows the degree of the water effect on the friction anisotropy of the rocks,mudstone(MU)>granite(GR)>fine sandstone(Fs)>argillaceous siltstone(As).The quantitative model is hopefully constructed for characterizing the relation between the anisotropic friction strength of rock and the moisture state in future.

关键词： anisotropy rotary friction test drilling response model(DD-model) effective stress law

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Economic analysis of hydrogen production from electrolyzed water technology by provinces in China

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Global Energy Interconnection 2024年第5期7卷 629-641页

作者： Xiao Han Jiangpeng Feng Yunhao Zhao Wenlei Bai China Electric power Research Institute Beijing 100192P.R.China state Grid pingshan County power supply company Shijiazhuang 050400P.R.China National Institute of Energy Development strategy North China Electric Power UniversityBeijing 102206P.R.China Electric Reliability Council of Texas(ERCOT) TaylorTX 76574U.S

A novel model for measuring the economics of hydrogen generation via electrolytic water projects was *** model overcomes the current problem of incomplete and inaccurate assessments of the price of producing hydrogen via water,which are caused by ignoring the indirect carbon costs of different power generation sources in the process of determining the cost of producing hydrogen via *** model was used to analyze the price of producing hydrogen via water electrolysis and its sensitivity to the electricity costs of hydrogen production and carbon prices in various provinces of *** the continuing increase in the penetration of novel energy in China’s power system and the gradual decline in electricity prices,the price of producing hydrogen via electrolytic water is expected to be close to or even lower than that of producing hydrogen via coal in the *** differences also have a significant impact on the price of producing hydrogen,which is typically higher in the southeastern coastal region than in the western region,because of the local price of electricity and the composition of the energy *** that have been effective in developing novel energy sources,such as Qinghai,sichuan,and others,have been effective in the hydrogen energy *** and other provinces with significant new energy development have a clear advantage in the hydrogen *** provinces with low hydrogen production costs can transport hydrogen to provinces with high hydrogen production costs through pipelines,hydrogen pipelines are planned from shaanxi to Henan and from Xinjiang to Nei *** study results reveal the relative economic advantages of producing hydrogen via water electrolysis under various energy and electricity price policies and provide new perspectives on China’s energy strategy and the growth of the hydrogen energy sector.

关键词： Hydrogen energy Hydrogen production cost Levelized cost Carbon emissions

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Measurement-While-Milling(MWM):An innovative approach for increasing the casing milling efficiency in deep drilling operations

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petroleum Research 2023年第3期8卷 360-369页

作者： Mohammed A.Namuq Mouhammed Jandal Berro Matthias Reich The American University of Kurdistan Petroleum Engineering DepartmentZakho Road42001DuhokKurdistan Region of IraqIraq H.Anger's sons-Drilling and Well Construction company Gutenbergstraße 3337235Hessisch LichtenauGermany TU Bergakademie Freiberg Institute of Petroleum EngineeringAgricolastr.2209599FreibergGermany

Deep boreholes are secured by steel tubes(casings)which are run in the hole and cemented in *** most cases,these casings are considered a permanent ***,sometimes they have to be removed in order to repair or abandon the *** the casing is cemented in place,it cannot be pulled,but needs to be milled to small chips which are flushed out of the borehole by the drilling *** of the main challenges in casing milling operations is continuous and complete chip *** the metal chips are too long,chip nests will grow around the milling *** a result,this will restrict the annulus flow area and affect the chip removal in *** obvious solution in such condition is to do round tripping and clean the chip nest which is associated with the risk of injuries,as well as,increasing the none-productive *** the worst case,the poor cleaning and circulation of chips can even end up with the milling string stucking problem in boreholes,consequently long-time fishing *** to the available literatures,hardly any study for identifying the chip shapes and accordingly adapting the operation parameters to the casing milling process environment downhole to keep milling within desired generated chip shapes and sizes could be *** paper presents an encouraging idea to monitor the milling process in real time by utilizing the acoustic emission signals(vibration modes)accompanied with the milling process to identify the desired chip shape and size *** laboratory tests have been carried out to investigate and study the acoustic emission signals accompanying the casing milling process to identify the chip shapes and *** preliminary test results show very good correlation and agreement between the chip length formed during those specific tests and the observed burst events in the measured *** study results have demonstrated the functionality of the new concept,and thus confirmed that it is a very promising idea to

关键词： Oil/Gas well casing milling Measurement while milling Casing milling chips shape detection Acoustic emission accompanied with casing milling operations Casing milling experiments

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Effect of γ-pGA Coated Urea on N-Release Rate and Tomato Growth

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Wuhan University Journal of Natural sciences 2014年第4期19卷 335-340页

作者： JIANG Yue LIU Liming LUO Guangfu ZHANG Zhanli Davidmark J HUANG Yingping Engineering Research Center of Eco-environment in Three Gorges Reservoir region Ministry of EducationChina Three Gorges University Hubei Yihua Chemical Industry company Ltd.

The anionic polymer γ-polyglutamic acid （γ-pGA） was used to coat urea and slow its dissolution. Three types of slow release urea （sRU） fertilizers （polymer coated urea with pore constriction, polymer coated urea with enzyme inhibitor and polymer coated urea with pore constriction and enzyme inhibitor） were prepared and tested for the N-release rate. After using sRU, the effect on the tomato growth was analyzed. The extracts of sRU were analyzed for NH3/NH4＋-N and NO3--N. The N-release rate was used to determine the optimum ratio of ingredients. The results show that the three types of sRU met the dissolution rate standards recommended by the Com- mittee of European Normalization. γ-pGA sRU increased the chlorophyll content of tomato （flowering stage） by an average of 100% compared with that grew in untreated urea. The results from soil analysis （0-60 cm in tomato pots） indicate that the content of NH3/NH4＋-N in sRU-treated pots was 25%-61% higher than that in soil from urea-treated pots during the growing period, while the content of NO3--N was nearly 50% lower after the tomato had been harvested. Newly formulated sRU fertilizer increases nitrogen up- take and reduces loss of applied nitrogen. plant growth is enhanced, a valu- able resource is conserved, and the aquatic environment benefits from de- creased level of nitrate in agricultural run-off.

关键词： γ-pGA slow release urea (sRU) fertilizer nitrogen releaserate tomato growth

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possibilities and prospects for producing silumins with different silicon contents using amorphous microsilica

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Transactions of Nonferrous Metals society of China 2020年第5期30卷 1406-1418页

作者： M.p.KUZ′MIN M.Yu.KUZ′MINA p.B.KUZ′MIN Irkutsk National Research Technical University 83 Lermontov St.IrkutskRussia Limited Liability company“United company RUsAL Engineering and Technology Center” 4 Industrial St.ShelekhovIrkutsk RegionRussia

The main objective of this work is to research complex physical-chemical processes of Al(l)-siO2 interface and develop a new technology for producing foundry silumins based on amorphous microsilica obtained from silicon production waste. Effective methods for producing hypoeutectic, eutectic, and hypereutectic silumins using amorphous microsilica were developed. Alloys with a silicon content of 7 wt.% were obtained by blowing preheated amorphous microsilica into the aluminum melt(t=900 ℃) along with the stream of argon followed by intense mixing. Alloys with a silicon content of 21 wt.% were manufactured by induction melting of a silicon-containing mixture(60% si O2, 40%Al + 20%3 Na F·2 Al F3) subjected to the presintering when the amorphous microsilica was reduced to crystalline silicon. It is found that crystalline silicon, which is formed during the roasting of the tableted burden, is smoothly absorbed by the aluminum melt. Aluminum oxide, obtained during the redox reaction, dissolves in cryolite, after which aluminum and silicon are fused together and transferred to the melt. The calculation of the economic efficiency of producing silumins using amorphous microsilica demonstrates a quick project payback period, as well as a high level of its profitability.

关键词： aluminum silicon silumins microsilica silicon dioxide

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