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DriftXMiner: A Resilient Process Intelligence Approach for Safe and Transparent Detection of Incremental Concept Drift in Process Mining
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作者 Puneetha B.H Manoj Kumar M.V +1 位作者 Prashanth B.S. Piyush Kumar Pareek 《Computers, Materials & Continua》 2026年第1期1086-1118,共33页
Processes supported by process-aware information systems are subject to continuous and often subtle changes due to evolving operational,organizational,or regulatory factors.These changes,referred to as incremental con... Processes supported by process-aware information systems are subject to continuous and often subtle changes due to evolving operational,organizational,or regulatory factors.These changes,referred to as incremental concept drift,gradually alter the behavior or structure of processes,making their detection and localization a challenging task.Traditional process mining techniques frequently assume process stationarity and are limited in their ability to detect such drift,particularly from a control-flow perspective.The objective of this research is to develop an interpretable and robust framework capable of detecting and localizing incremental concept drift in event logs,with a specific emphasis on the structural evolution of control-flow semantics in processes.We propose DriftXMiner,a control-flow-aware hybrid framework that combines statistical,machine learning,and process model analysis techniques.The approach comprises three key components:(1)Cumulative Drift Scanner that tracks directional statistical deviations to detect early drift signals;(2)a Temporal Clustering and Drift-Aware Forest Ensemble(DAFE)to capture distributional and classification-level changes in process behavior;and(3)Petri net-based process model reconstruction,which enables the precise localization of structural drift using transition deviation metrics and replay fitness scores.Experimental validation on the BPI Challenge 2017 event log demonstrates that DriftXMiner effectively identifies and localizes gradual and incremental process drift over time.The framework achieves a detection accuracy of 92.5%,a localization precision of 90.3%,and an F1-score of 0.91,outperforming competitive baselines such as CUSUM+Histograms and ADWIN+Alpha Miner.Visual analyses further confirm that identified drift points align with transitions in control-flow models and behavioral cluster structures.DriftXMiner offers a novel and interpretable solution for incremental concept drift detection and localization in dynamic,process-aware systems.By integrating statistical signal accumulation,temporal behavior profiling,and structural process mining,the framework enables finegrained drift explanation and supports adaptive process intelligence in evolving environments.Its modular architecture supports extension to streaming data and real-time monitoring contexts. 展开更多
关键词 Process mining concept drift gradual drift incremental drift clustering ensemble techniques process model event log
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Different extractable pools of Cd and Pb in agricultural soil under amendments:Water-soluble concentration sensitively indicates metal availability 被引量:1
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作者 Zidi Wang Wenyao Tang +8 位作者 Xiaodong Ding Qiang Dong Yingying Guo Guangliang Liu Yanwei Liu Yong Liang Yongguang Yin Yong Cai Guibin Jiang 《Journal of Environmental Sciences》 2025年第4期297-308,共12页
Identification of the most appropriate chemically extractable pool for evaluating Cd and Pb availability remains elusive,hindering accurate assessment on environmental risks and effectiveness of remediation strategies... Identification of the most appropriate chemically extractable pool for evaluating Cd and Pb availability remains elusive,hindering accurate assessment on environmental risks and effectiveness of remediation strategies.This study evaluated the feasibility of European Community Bureau of Reference(BCR)sequential extraction,Ca(NO_(3))_(2)extraction,and water extraction on assessing Cd and Pb availability in agricultural soil amended with slaked lime,magnesium hydroxide,corn stover biochar,and calcium dihydrogen phosphate.Moreover,the enriched isotope tracing technique(^(112)Cd and^(206)Pb)was employed to evaluate the aging process of newly introduced Cd and Pbwithin 56 days’incubation.Results demonstrated that extractable pools by BCR and Ca(NO_(3))_(2)extraction were little impacted by amendments and showed little correlation with soil pH.This is notable because soil pH is closely linked to metal availability,indicating these extraction methods may not adequately reflect metal availability.Conversely,water-soluble concentrations of Cd and Pb were markedly influenced by amendments and exhibited strong correlations with pH(Pearson’s r:-0.908 to-0.825,P<0.001),suggesting water extraction as a more sensitive approach.Furthermore,newly introduced metals underwent a more evident aging process as demonstrated by acid-soluble and water-soluble pools.Additionally,water-soluble concentrations of essential metals were impacted by soil amendments,raising caution on their potential effects on plant growth.These findings suggest water extraction as a promising and attractive method to evaluate Cd and Pb availability,which will help provide assessment guidance for environmental risks caused by heavy metals and develop efficient remediation strategies. 展开更多
关键词 Heavy metals water-soluble concentrations Enriched stable isotopes Soil amendments Sequential extraction Soil pH
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Synthesis of a water-soluble macromolecular light stabilizer containing hindered amine structures 被引量:6
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作者 Wei Ma Mei Meng +2 位作者 Xue Jiang Bing-Tao Tang Shu-Fen Zhang 《Chinese Chemical Letters》 SCIE CAS CSCD 2013年第2期153-155,共3页
Received 26 September 2012 Received in revised form 18 December 20 Accepted 1 January 2013 Available online 4 February 2013
关键词 water-soluble macromolecular lightstabilizerHindered amineLightfastness of reactive dyesFinishing
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Si-rhodamine based water-soluble fluorescent probe for bioimaging of Cu^(+) 被引量:1
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作者 Xiaoyun Chai Weiwei Zhu +1 位作者 Qingguo Meng Ting Wang 《Chinese Chemical Letters》 SCIE CAS CSCD 2021年第1期210-213,共4页
A Si-substituted rhodamine based water-soluble fluorescent probe bearing a tetrathia-azacrown was designed for fluorescence imaging of Cu^(+) with substantial affinity and selectivity.In physiological condition,the de... A Si-substituted rhodamine based water-soluble fluorescent probe bearing a tetrathia-azacrown was designed for fluorescence imaging of Cu^(+) with substantial affinity and selectivity.In physiological condition,the developed probe with outstanding water-solubility exhibits ultrahigh sensitivity to Cu^(+),ensuring the reliable fluorescence imaging in vivo. 展开更多
关键词 Si-rhodamine NEAR-INFRARED WATER-SOLUBILITY Fluorescence imaging Copper
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Water-soluble organic nitrogen in PM_(2.5) around the Danjiangkou Reservoir:Concentration, sources, and transport pathways
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作者 Chunyan Xiao Pengbo Li +4 位作者 Xiaoshu Chen Tongqian Zhao Xiaoming Guo Yuxiao He Guizhen Wang 《Journal of Environmental Sciences》 2025年第10期757-770,共14页
Water-soluble organic nitrogen(WSON)affects the formation,hygroscopicity,acidity of organic aerosols,and nitrogen biogeochemical cycles.However,qualitative and quantitative characterizations of WSON remain limited due... Water-soluble organic nitrogen(WSON)affects the formation,hygroscopicity,acidity of organic aerosols,and nitrogen biogeochemical cycles.However,qualitative and quantitative characterizations of WSON remain limited due to its chemical complexity.In the study,1-year field samples of particulate matter 2.5(PM_(2.5))were collected fromJune 2022 to May 2023 to analyze the WSON concentration in PM_(2.5),and correlation analysis,positive matrix factor(PMF),and potential source contribution function(PSCF)modelswere employed to elucidate WSON source apportionment and transport pathways.The results revealed that the mean WSON concentrations reached 1.98±2.64μg/m^(3) with a mean WSON to water-soluble total nitrogen(WSTN)ratio of 21%.Further,WSON concentration exhibited a seasonal variation trend,with higher values in winter and lower in summer.Five sources were identified as contributors to WSON in PM_(2.5) within the reservoir area through a comprehensive analysis including correlation analysis,PSCF and concentration weighted trajectory(CWT),and PMF analyses.These sources were agricultural,dust,combustion,traffic,and industrial sources,of which agricultural source emerged as the primary contributor(76.69%).The atmosphere in the reservoir area were primarily influenced by the transport of northeastern air masses,local agricultural activities,industrial cities along the trajectory,and coastal regions,exerting significant influences on the concentration of WSON in the reservoir area.The findings of this study addressed the research gap concerning organic nitrogen in PM_(2.5) within the reservoir area,thereby offering a theoretical foundation and data support in controlling nitrogen pollution in the Danjiangkou Reservoir area. 展开更多
关键词 PM_(2.5) water-soluble organic nitrogen Source apportionment Potential source location Danjiangkou Reservoir
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Influence of Mining Speed on Stope Energy in Deep Mines
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作者 Zhi-gang Deng Shang Wang +1 位作者 Yun-long MO Wei-jian Liu 《Applied Geophysics》 2025年第3期848-856,897,共10页
Enhancing the mining speed of a working face has become the primary approach to achieve high production and efficiency in coal mines,thereby further improving the production capacity.However,the problem of rock bursts... Enhancing the mining speed of a working face has become the primary approach to achieve high production and efficiency in coal mines,thereby further improving the production capacity.However,the problem of rock bursts resulting from this approach has become increasingly serious.Therefore,to implement coal mine safety and efficient extraction,the impact of deformation pressure caused by different mining speeds should be considered,and a reasonable mining speed of the working face should be determined.The influence of mining speed on overlying rock breaking in the stope is analyzed by establishing a key layer block rotation and subsidence model.Results show that with the increasing mining speed,the compression amount of gangue in the goaf decreases,and the rotation and subsidence amount of rock block B above goaf decreases,forcing the rotation and subsidence amount of rock block A above roadway to increase.Consequently,the contact mode between rock block A and rock block B changes from line contact to point contact,and the horizontal thrust and shear force between blocks increase.The increase in rotation and subsidence of rock block A intensifies the compression degree of coal and rock mass below the key layer,thereby increasing the stress concentration degree of coal and rock mass as well as the total energy accumulation.In addition,due to the insufficient compression of gangue in the goaf,the bending and subsidence space of the far-field key layer are limited,the length of the suspended roof increases,and the influence range of mining stress and the energy accumulation range expand.Numerical test results and underground microseismic monitoring results verify the correlation between mining speed and stope energy,and high-energy events generally appear 1-2 d after the change in mining speed.On this basis,the statistical principle confirms that the maximum mining speed of the working face at 6 m/d is reasonable. 展开更多
关键词 ROCKBURST mining speed overburden structure ENERGY statistics
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Evolution of water-soluble organic aerosol composition from clean days to haze episodes in rural area of North China Plain
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作者 Chun Chen Long Jia +15 位作者 Zhiqiang Zhang Jian Gao Yanmei Qiu Junling Li Rui Gao Ping Li Qun Zhang Zhijie Li Jiaxing Sun Nan Ma Wanyun Xu Yongfu Xu Xiaole Pan Pingqing Fu Zifa Wang Yele Sun 《Journal of Environmental Sciences》 2025年第12期228-241,共14页
Water-soluble organic aerosol(WSOA)plays a significant role in air quality and human health.Here we characterized the chemical properties and molecular compositions of WSOA at a rural site in North China Plain during ... Water-soluble organic aerosol(WSOA)plays a significant role in air quality and human health.Here we characterized the chemical properties and molecular compositions of WSOA at a rural site in North China Plain during winter using a high-resolution aerosol mass spectrometer and electrospray ionization high-resolution orbitrap mass spectrometer(ESI-HRMS).Our results show that the mass concentration of WSOA was significantly higher than that observed in Beijing in winter 2020,contributing about 56%of OA on average.CHO compounds(56%-74%)and CHN compounds(66%-80%)dominated in negative mode and positive mode,respectively,while CHON accounted for 15%-41%across both modes.The chemical characteristics of WSOA varied with polluted levels and between day and night.As pollution intensified,the abundance of CHO-compounds with condensed aromatics increased by 9%and the number of highly oxygenated molecules(HOMs)molecular formula detected in server haze was more than double that of clean days.CHO-compounds with ten carbon atoms(C_(10))were more abundant at night while those with nine carbon atoms(C_(9))were higher during the day.High levels of CHN+compounds were linked to nighttime biomass burning,whereas CHON compounds were more abundant during the day.Increased pollution also led to the formation of more complex CHON-compounds,indicating that organonitrates continue to play a significant role in rural pollution. 展开更多
关键词 water-soluble organic aerosol Molecular compositions Aerosol mass spectrometer High-resolution orbitrap mass spectrometer North China Plain
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Synthesis and antitumor activity of water-soluble poly(aminoheterocyclic amine)s (I): N,N,N',N'-tetra[2-(4-amino-5-substituted-s-triazol-3-yl sulfanyl)ethyl] -1,4-benzyldiamine salts
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作者 Guo Qiang Hu, Song Qiang Xie, Wen Long Huang Institute of Pharmacy, Henan University, Kaifeng 475001, China China Pharmaceutical University, Nanjing 210009, China 《Chinese Chemical Letters》 SCIE CAS CSCD 2007年第2期124-126,共3页
Five water-soluble poly(aminoheterocyclic amine)s containing s-triazole ring were synthesized as respective HC1 salts (5a-5e). Biological activities in L1210 (murine leukemia) and Chinese hamster ovary (CHO) cell line... Five water-soluble poly(aminoheterocyclic amine)s containing s-triazole ring were synthesized as respective HC1 salts (5a-5e). Biological activities in L1210 (murine leukemia) and Chinese hamster ovary (CHO) cell lines were investigated via IC50 cytotoxicity determinations. The tide compounds represented moderate cytotoxicity (low IC50 values between 15 and 68μmol/L) in L1210 but high cytotoxicity (lower IC50 values: 0.25,0.018,0.014μmol/L for Sa-5e, respectively) in CHO cell lines, while the corresponding HC1 salts of the intermediates (3a-3e) without polyamine tether and starting materials amino-s-triazoles (1a-1e) showed poor or no activities against the above cell lines. 展开更多
关键词 TRIAZOLE POLYAMINE water-soluble Antitumor activity
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Water-Soluble Organic Acids at Deep-Ultradeep Depth in Chinese Sedimentary Basins:Experimental Results and Geological Significances
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作者 Pengpeng Li Quanyou Liu +2 位作者 Zheng Zhou Jing Li Shixin Zhou 《Journal of Earth Science》 2025年第6期2546-2560,共15页
Water-soluble organic acid anions(WSOAA)in subsurface water have been intensively studied during past several decades.They are used as natural gas precursor,tracer for the movement of underground fluid,indicator for p... Water-soluble organic acid anions(WSOAA)in subsurface water have been intensively studied during past several decades.They are used as natural gas precursor,tracer for the movement of underground fluid,indicator for porosity improvement,and detecter of deep subsurface life on the Earth.However,little is known about the distributions and origins of organic acids at deep-ultradeep depth underground.Herein,we collected twenty-nine source rock samples covering a wide maturity range from the Ordos,Qinshui,Junggar,Minhe,and Southern North China basins,as well as six subsurface water samples with depth between 6544 and 8396 m from industrial gas producing wells in the Tarim Basin,China.We carried out pyrolysis experiments at various temperatures(250–450℃)to investigate the role of water on the generation of organic acids.Results show that there are considerable amounts of WSOAA detected in both high-over mature source rocks and deep-ultradeep subsurface water.WSOAA mainly consists of monocarboxylates,predominately formate and acetate.High-TOC oil-generating source rock has low production rate of organic acids due to lack of hydrogen.Different source rocks have distinct ratios of formate to acetate concentration,expressed as c(formate)/c(acetate),which is due to significant differences in both initial molecular structure and metabolite.This indicates that c(formate)/c(acetate)can be used to distinguish types of organic matters(OMs).Concentrations of WSOAA show a“sharp decrease-slight increase-slow decrease”evolution trend with progressive maturity.Moreover,there are higher production rates of organic acids under hydrous pyrolysis experiments at≥400℃.All geochemical signatures indicate that at both deep-ultradeep depth and high-over mature stages,the formation of organic acids is attributed to the thermochemical oxidation of organic components by mainly hydroxyl radicals,challenging the traditional model of organic acid evolution.This work suggests that petroleum exploration can be extended to great depths in sedimentary basins,when formation temperatures are not exceeding 230℃. 展开更多
关键词 water-soluble organic acids high-over mature stages deep-ultradeep zone thermochemical oxidation of organic components hydroxyl radicals petroleum geology
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Synthesis and photoluminescent properties of water-soluble TbF_3 nanoparticles
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作者 王振领 张新磊 +1 位作者 常加忠 李春阳 《Journal of Rare Earths》 SCIE EI CAS CSCD 2011年第11期1018-1021,共4页
Monodispersed and water-soluble TbF3 nanoparticles were synthesized at a relatively low temperature in aqueous solution using citric acid as an additive,and characterized by X-ray diffraction(XRD),field emission sca... Monodispersed and water-soluble TbF3 nanoparticles were synthesized at a relatively low temperature in aqueous solution using citric acid as an additive,and characterized by X-ray diffraction(XRD),field emission scanning electron microscopy(FE-SEM),Fourier transform infrared spectra(FTIR),photoluminescence(PL) spectra and lifetime.The as-prepared TbF3 nanoparticles had orthorhombic structure and were composed of monodispersed spherical particles with an average particle size of 50 nm.The excitation spectrum of TbF3 nanoparticles obtained by monitoring the emission of Tb3+ at 543 nm was composed of the characteristics f-f transition lines within the Tb3+ 4f8 configuration.Under the UV light irradiation,the emission spectrum exhibited four obvious lines centered at 489,543,589,and 618 nm,which was corresponding to the 5D4→7FJ(J=6,5,4,3) transitions of the Tb3+ ions in TbF3 nanoparticles. 展开更多
关键词 Tphotoluminescence TbF3 MONODISPERSED water-soluble rare earths
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Analysis of the Application of Mechanical and Electrical Equipment Supporting Technology in Coal Mine Filling Mining Face
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作者 Sanmin Wang 《Journal of World Architecture》 2025年第3期95-101,共7页
In the context of increasing demand for coal mine resources in China’s current socio-economic development,traditional mining methods have been difficult to effectively meet the requirements of safety production and e... In the context of increasing demand for coal mine resources in China’s current socio-economic development,traditional mining methods have been difficult to effectively meet the requirements of safety production and environmental protection.As a result,coal mine filling mining technology has emerged,which can effectively achieve the goal of controlling surface subsidence in practical applications,while also significantly improving the recovery rate of coal resources.Based on this,this study will first elaborate on the characteristics of filling mining technology,and then analyze the key points of the application of supporting technology for mechanical and electrical equipment in the corresponding working face based on actual cases,in order to provide support for improving the efficiency of coal mining. 展开更多
关键词 Coal mine Filling mining face Mechanical and electrical equipment
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Benzothiadiazole-based water-soluble macrocycle:Synthesis,aggregation-induced emission and selective detection of spermine
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作者 Shuo Li Qianfa Liu +3 位作者 Lijun Mao Xin Zhang Chunju Li Da Ma 《Chinese Chemical Letters》 SCIE CAS CSCD 2024年第11期314-317,共4页
Reported here is the synthesis of a new macrocycle bearing anionic carboxylate groups with water-soluble aggregation-induced emission(AIE).The water-soluble macrocycle without typical AIE luminogens is constructed bas... Reported here is the synthesis of a new macrocycle bearing anionic carboxylate groups with water-soluble aggregation-induced emission(AIE).The water-soluble macrocycle without typical AIE luminogens is constructed based on the building block of benzothiadiazole.It exhibits a remarkable AIE effect.This watersoluble macrocycle can selectively bind different types of biogenic amines in aqueous media with the tightest binding towards spermine.The fluorescence enhancement induced by supramolecular encapsulation is used to detect spermine. 展开更多
关键词 MACROCYCLE water-soluble Aggregation-induced emission Biogenic amines Host-vip interaction
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Depth-dependent mechanical-seepage behavior and safety mining distance of the steeply inclined coal mine underground reservoir
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作者 Ersheng Zha Hongfei Duan +5 位作者 Mingbo Chi Jiulin Fan Jianjun Hu Baoyang Wu Cong Yu Jiancheng Tong 《International Journal of Mining Science and Technology》 2025年第8期1341-1355,共15页
Coal mine underground reservoir(CMUR) technology mitigates water scarcity in China's coal-rich western regions but lacks tailored solutions for steeply inclined coal seams.This study develops a novel framework of ... Coal mine underground reservoir(CMUR) technology mitigates water scarcity in China's coal-rich western regions but lacks tailored solutions for steeply inclined coal seams.This study develops a novel framework of steeply inclined coal mine underground reservoirs(SICMUR),which is a paradigm shift from conventional CMUR that the coal seam itself serves as the reservoir floor,challenging conventional designs due to depth-dependent permeability and mechanical constraints.Triaxial mechanical-seepage tests on Xinjiang Wudong coal samples(100,200,300 m depths) revealed a 3.5 MPa triaxial strength increase per 100 m depth and a 58-fold post-peak permeability surge at 300 versus 100 m.Similar model simulations revealed mining-induced stress redistribution and significant deformation effects,particularly subsidence and water-conducting fractures during lower coal seam mining.Results indicate a minimum 40 m safety distance between reservoirs and lower coal seams.Critical construction parameters were investigated for Wudong mine SICMUR as collapse zone heights(9.9–12.31 m) and waterconducting fracture zone heights(31.96–37.40 m).This work systematically bridges SICMUR concepts to field implementation,offering a framework for water preservation in steeply inclined mining while addressing safety concerns,providing a new approach for water reservation in steeply inclined coal mining. 展开更多
关键词 Steeply inclined coal mine underground reservoir Mechanical-seepage coupling Similar simulation Safety mining distance Stability analysis
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Nonlinear Doping, Chemical Passivation and Photoluminescence Mechanism in Water-Soluble Silicon Quantum Dots by Mechanochemical Synthesis
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作者 黄思敏 钱波 +1 位作者 沈若曦 谢永林 《Chinese Physics Letters》 SCIE CAS CSCD 2018年第3期62-66,共5页
A series of boron- and phosphorus-doped silicon wafers are used to prepare a series of doped silicon nanocrystals (nc-Si) by high-energy ball milling with carboxylic acid-terminated surface. The sizes of the nc-Si s... A series of boron- and phosphorus-doped silicon wafers are used to prepare a series of doped silicon nanocrystals (nc-Si) by high-energy ball milling with carboxylic acid-terminated surface. The sizes of the nc-Si samples are demonstrated to be 〈 S nm. The doping levels of the nc-Si are found to be nonlinearly dependent on the original doping level of the wafers by x-ray photoelectron spectroscopy measurement. It is found that the nonlinear doping process will lead to the nonlinear chemical passivation and photoluminescence (I3L) intensity evolution. The doping, chemical passivation and PL mechanisms of the doped nc-Si samples prepared by mechanochemical synthesis are analyzed in detail. 展开更多
关键词 SI Nonlinear Doping Chemical Passivation and Photoluminescence Mechanism in water-soluble Silicon Quantum Dots by Mechanochemical Synthesis
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Safe mining technology of undersea metal mine 被引量:15
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作者 彭康 李夕兵 +2 位作者 万串串 彭述权 赵国彦 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2012年第3期740-746,共7页
Xinli district of Sanshandao Gold Mine is the first subsea metal mine in China.To achieve 6 kt/d production capacity under the premise of safe mining,high-intensity mining might destroy the in-situ stress filed and th... Xinli district of Sanshandao Gold Mine is the first subsea metal mine in China.To achieve 6 kt/d production capacity under the premise of safe mining,high-intensity mining might destroy the in-situ stress filed and the stability of rockmass.According to sampling and testing of ore-rock and backfill and in-situ stress field measurement,safety factor method calculation model based on stress-strain strength reduction at arbitrary points and Mohr-Coulomb yield criterion was established and limit displacement subsidence values under the safety factor of different limit stoping steps were calculated.The results from three years in-situ mining and strata movement monitoring using multi-point displacements meter showed that the lower settlement frame stope hierarchical level filling mining method,mining sequence are reasonable and rockmass stability evaluation using safety factor method,in-situ real-time monitoring can provide the technical foundation for the safety of seabed mining. 展开更多
关键词 subsea bedrock mining frame stope upward horizontal slicing and filling mining method safety factor method multi-point displacement measurement
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Mechanical response of roof rock mass unloading during continuous mining process in underground mine 被引量:9
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作者 胡建华 雷涛 +2 位作者 周科平 罗先伟 杨念哥 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2011年第12期2727-2733,共7页
Taking the test stopes during continuous mining induced roof caving of Tongkeng ore-body No.92 as example, the calculation flow of unloading analysis was established. According to the unloading region division method ... Taking the test stopes during continuous mining induced roof caving of Tongkeng ore-body No.92 as example, the calculation flow of unloading analysis was established. According to the unloading region division method of the affected zone theory, and the deterioration laws of mechanics parameters of unloading rock mass, the continuous mining process in underground mine was analyzed by the software MIDAS/GTS, the mechanical response of roof rock mass unloading was studied, and the differences were analyzed with the conventional simulation. The result shows that the maximum tensile stress, subsidence displacement and equivalent plastic strain of roof rock mass are 1.5 MPa, 20 cm and 1.5% in the unloading analysis, while 1.0 MPa, 13 cm and 0.9% in the conventional analysis. The values of unloading analysis, which are also closer to the actual situation, are greater than those of conventional analysis; the maximum step in continuous mining is 48 m, which shows that the induced treatment of the roof should be carried out after 2 mining steps 展开更多
关键词 continuous mining mining-unload rock mass mechanics mining-unload disturbance region dynamic mechanical parameters
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Release Model of Water-soluble Chitosan Nanoparticles for Protein Delivery 被引量:2
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作者 王春 孙胜玲 +2 位作者 肖惠宁 何北海 杨连生 《Agricultural Science & Technology》 CAS 2009年第3期144-147,共4页
[Objective] The experiment aimed to explore release rule of water-soluble chitosan (WSC) in vitro. [Method]The bovine serum albumin(BSA) was taken as a model protein drug and some existing release models such as Kinet... [Objective] The experiment aimed to explore release rule of water-soluble chitosan (WSC) in vitro. [Method]The bovine serum albumin(BSA) was taken as a model protein drug and some existing release models such as Kinetics model, Gompertz model, Weibull model, Higuchi model and Logistic model were used to fit the BSA release profile from WSC carriers. [Result] Except Higuchi model and Logistic model, other models could fit BSA release profile better. [Conclusion] Gompertz two-order kinetics model could fit the release of WSC nano-particles better and model parameters had practical physical meaning. 展开更多
关键词 water-soluble chitosan Nano-particle carriers Protein delivery Release model
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A study of the properties of hydrophobically associating water-soluble polymers used in drilling fluids
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作者 舒福昌 史茂勇 +4 位作者 张岩 张峰 黄红玺 向兴金 王建华 《Petroleum Science》 SCIE CAS CSCD 2004年第4期57-61,共5页
Hydrophobically associating water-soluble polymers (HPAP) have been synthesized from acrylamide(AM), acrylate (AA), 2-acrylamido-2-methyl propane sulfonic acid (AMPS) and hydrophobic monomer (AP) in aqueous solution... Hydrophobically associating water-soluble polymers (HPAP) have been synthesized from acrylamide(AM), acrylate (AA), 2-acrylamido-2-methyl propane sulfonic acid (AMPS) and hydrophobic monomer (AP) in aqueous solution by radical polymerization. New polymer drilling fluids are made up of HPAP, which is used as viscosifiers and encapsulation agents. Properties of this system are reported in this paper. Results indicate that this system has a high value of yield point to plastic viscosity (YP/PV≥0.7), high viscosity at a low-shear rate (LSRV≥30000mPa·s), excellent shear thinning behavior, good solid-carrying behavior, resistance to shear, good thermal stability (as high as 140℃) and salt resistance. The system has excellent behavior in high-density solution of NaCl and in calcium and magnesium rich saline solutions. Hence, HPAP also can be used in saltwater polymer drilling fluids. 展开更多
关键词 Hydrophobically associating water-soluble polymers drilling fluids VISCOSITY salt resistance
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Effect of Different Environmental Conditions on Algicidal Effect of Water-soluble Extracts of Chinese Chive
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作者 刘文桃 石光辉 +2 位作者 董昆明 赵海涛 封克 《Agricultural Science & Technology》 CAS 2012年第2期397-400,456,共5页
[Objective] The paper was to study the algicidal effect of water-soluble extracts of Chinese chive under different environmental conditions, so as to provide reference for further study and development of new algicida... [Objective] The paper was to study the algicidal effect of water-soluble extracts of Chinese chive under different environmental conditions, so as to provide reference for further study and development of new algicidal substances. [Method] The effects of water-soluble extracts of Chinese chive on the growth of Microcystis aeruginosa under different pH, light and aeration conditions were compared and studied. [Result] The growth inhibition rate of water-soluble extracts of Chinese chive on M. aeruginosa was greater than 90% under different pH conditions. With the growth of M. aeruginosa, the culture liquid with different initial pH was finally tended to 9-9.5. The growth inhibition rate of water-soluble extracts of Chinese chive on algae cell increased with the prolongation of culture time within the light intensity range of 1 000-4 000 lx. The inhibition effect of water-soluble extracts of Chinese chive on M. aeruginosa under low light intensity(1 000 lx)was better than that under high light intensity, the best light intensity for growth was not conducive to the exertion of allelopathic effect. Meanwhile, aeration condition was more conducive to the inhibition effect of water-soluble extracts of Chinese chive on the growth of M. aeruginosa. [Conclusion] pH, light and aeration conditions all affected the inhibition effect of water-soluble extracts of Chinese chive treated by high temperature on M. aeruginosa. Understanding the effect of these environmental factors on algicidal effect of allelochemicals could provide reference for further study and development of new algicidal substances. 展开更多
关键词 Microcystis aeruginosa water-soluble extracts of Chinese chive PH LIGHT AERATION
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Effect of thatch on water-soluble phosphorus of pasture soil fertilized with broiler litter
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作者 陈欣 张庆忠 M.L.Cabrera 《Journal of Forestry Research》 SCIE CAS CSCD 2002年第1期71-73,共3页
The presence of a thatch layer in established pastures could reduce the contact between broiler litter and soil, thus increasing the potential for surface runoff contamination with litter P. We conducted a laboratory ... The presence of a thatch layer in established pastures could reduce the contact between broiler litter and soil, thus increasing the potential for surface runoff contamination with litter P. We conducted a laboratory study to evaluate the effect of a thatch layer on the dynamics of water-soluble P in undisturbed cores taken from a pasture. Cores with and without a thatch layer received a surface application of broiler litter (5 thm-2) and were incubated at 25 oC for 56 d. The result showed that on the soil surface the contents of water soluble-P (39 kghm-2) of the cores with the thatch layer was higher than that (20 kghm-2) of the cores without the thatch layer. Therefore on well-established pastures fertilized with broiler litter, the presence of a thatch layer might lead to high concentrations of water-soluble P on the soil surface. 展开更多
关键词 PASTURES water-soluble phosphorus Broiler litter
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