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Efficient and Stable Perovskite Solar Cells and Modules Enabled by Tailoring Additive Distribution According to the Film Growth Dynamics
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作者 Mengen Ma Cuiling Zhang +5 位作者 Yujiao Ma Weile Li Yao Wang Shaohang Wu Chong Liu Yaohua Mai 《Nano-Micro Letters》 SCIE EI CAS 2025年第2期387-400,共14页
Gas quenching and vacuum quenching process are widely applied to accelerate solvent volatilization to induce nucleation of perovskites in blade-coating method.In this work,we found these two pre-crystallization proces... Gas quenching and vacuum quenching process are widely applied to accelerate solvent volatilization to induce nucleation of perovskites in blade-coating method.In this work,we found these two pre-crystallization processes lead to different order of crystallization dynamics within the perovskite thin film,resulting in the differences of additive distribution.We then tailor-designed an additive molecule named 1,3-bis(4-methoxyphenyl)thiourea to obtain films with fewer defects and holes at the buried interface,and prepared perovskite solar cells with a certified efficiency of 23.75%.Furthermore,this work also demonstrates an efficiency of 20.18%for the large-area perovskite solar module(PSM)with an aperture area of 60.84 cm^(2).The PSM possesses remarkable continuous operation stability for maximum power point tracking of T_(90)>1000 h in ambient air. 展开更多
关键词 Gas quenching Additive distribution Buried passivation Blade coating Crystallization dynamics
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Differential distribution of PINK1 and Parkin in the primate brain implies distinct roles
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作者 Yanting Liu Wei Huang +8 位作者 Jiayi Wen Xin Xiong Ting Xu Qi Wang Xiusheng Chen Xianxian Zhao Shihua Li Xiaojiang Li Weili Yang 《Neural Regeneration Research》 SCIE CAS 2025年第4期1124-1134,共11页
The vast majority of in vitro studies have demonstrated that PINK1 phosphorylates Parkin to work together in mitophagy to protect against neuronal degeneration.However,it remains largely unclear how PINK1 and Parkin a... The vast majority of in vitro studies have demonstrated that PINK1 phosphorylates Parkin to work together in mitophagy to protect against neuronal degeneration.However,it remains largely unclear how PINK1 and Parkin are expressed in mammalian brains.This has been difficult to address because of the intrinsically low levels of PINK1 and undetectable levels of phosphorylated Parkin in small animals.Understanding this issue is critical for elucidating the in vivo roles of PINK1 and Parkin.Recently,we showed that the PINK1 kinase is selectively expressed as a truncated form(PINK1–55)in the primate brain.In the present study,we used multiple antibodies,including our recently developed monoclonal anti-PINK1,to validate the selective expression of PINK1 in the primate brain.We found that PINK1 was stably expressed in the monkey brain at postnatal and adulthood stages,which is consistent with the findings that depleting PINK1 can cause neuronal loss in developing and adult monkey brains.PINK1 was enriched in the membrane-bound fractionations,whereas Parkin was soluble with a distinguishable distribution.Immunofluorescent double staining experiments showed that PINK1 and Parkin did not colocalize under physiological conditions in cultured monkey astrocytes,though they did colocalize on mitochondria when the cells were exposed to mitochondrial stress.These findings suggest that PINK1 and Parkin may have distinct roles beyond their well-known function in mitophagy during mitochondrial damage. 展开更多
关键词 NEURODEGENERATION PARKIN Parkinson’s disease PINK1 subcellular distribution
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Pretreatment red blood cell distribution width as a predictive marker for postoperative complications after laparoscopic pancreatoduodenectomy
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作者 Xian-Rang Cao Yin-Long Xu +4 位作者 Jia-Wei Chai Kai Zheng Jun-Jie Kong Jun Liu Shun-Zhen Zheng 《World Journal of Gastrointestinal Oncology》 SCIE 2025年第1期143-157,共15页
BACKGROUND Red blood cell distribution width(RDW)is associated with the development and progression of various diseases.AIM To explore the association between pretreatment RDW and short-term outcomes after laparoscopi... BACKGROUND Red blood cell distribution width(RDW)is associated with the development and progression of various diseases.AIM To explore the association between pretreatment RDW and short-term outcomes after laparoscopic pancreatoduodenectomy(LPD).METHODS A total of 804 consecutive patients who underwent LPD at our hospital between March 2017 and November 2021 were retrospectively analyzed.Correlations between pretreatment RDW and clinicopathological characteristics and short-term outcomes were investigated.RESULTS Patients with higher pretreatment RDW were older,had higher Eastern Cooperative Oncology Group scores and were associated with poorer short-term outcomes than those with normal RDW.High pretreatment RDW was an independent risk factor for postoperative complications(POCs)(hazard ratio=2.973,95%confidence interval:2.032-4.350,P<0.001)and severe POCs of grade IIIa or higher(hazard ratio=3.138,95%confidence interval:2.042-4.824,P<0.001)based on the Clavien-Dino classification system.Subgroup analysis showed that high pretreatment RDW was an independent risk factor for Clavien-Dino classi-fication grade IIIb or higher POCs,a comprehensive complication index score≥26.2,severe postoperative pancreatic fistula,severe bile leakage and severe hemorrhage.High pretreatment RDW was positively associated with the neutrophil-to-lymphocyte ratio and platelet-to-lymphocyte ratio and was negatively associated with albumin and the prognostic nutritional index.CONCLUSION Pretreatment RDW was a special parameter for patients who underwent LPD.It was associated with malnutrition,severe inflammatory status and poorer short-term outcomes.RDW could be a surrogate marker for nutritional and inflammatory status in identifying patients who were at high risk of developing POCs after LPD. 展开更多
关键词 BIOMARKER Laparoscopic pancreatoduodenectomy Postoperative complication Red blood cell distribution width Short-term outcomes
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Effects of aggregate size distribution and carbon nanotubes on the mechanical properties of cemented gangue backfill samples under true triaxial compression
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作者 Qian Yin Fan Wen +7 位作者 Zhigang Tao Hai Pu Tianci Deng Yaoyao Meng Qingbin Meng Hongwen Jing Bo Meng Jiangyu Wu 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS 2025年第2期311-324,共14页
The mechanical behavior of cemented gangue backfill materials(CGBMs)is closely related to particle size distribution(PSD)of aggregates and properties of cementitious materials.Consequently,the true triaxial compressio... The mechanical behavior of cemented gangue backfill materials(CGBMs)is closely related to particle size distribution(PSD)of aggregates and properties of cementitious materials.Consequently,the true triaxial compression tests,CT scanning,SEM,and EDS tests were conducted on cemented gangue backfill samples(CGBSs)with various carbon nanotube concentrations(P_(CNT))that satisfied fractal theory for the PSD of aggregates.The mechanical properties,energy dissipations,and failure mechanisms of the CGBSs under true triaxial compression were systematically analyzed.The results indicate that appropriate carbon nanotubes(CNTs)effectively enhance the mechanical properties and energy dissipations of CGBSs through micropore filling and microcrack bridging,and the optimal effect appears at P_(CNT)of 0.08wt%.Taking PSD fractal dimension(D)of 2.500 as an example,compared to that of CGBS without CNT,the peak strength(σ_(p)),axial peak strain(ε_(1,p)),elastic strain energy(Ue),and dissipated energy(U_(d))increased by 12.76%,29.60%,19.05%,and90.39%,respectively.However,excessive CNTs can reduce the mechanical properties of CGBSs due to CNT agglomeration,manifesting a decrease inρ_(p),ε_(1,p),and the volumetric strain increment(Δε_(v))when P_(CNT)increases from 0.08wt%to 0.12wt%.Moreover,the addition of CNTs improved the integrity of CGBS after macroscopic failure,and crack extension in CGBSs appeared in two modes:detour and pass through the aggregates.Theσ_(p)and U_(d)firstly increase and then decrease with increasing D,and porosity shows the opposite trend.Theε_(1,p)andΔε_(v)are negatively correlated with D,and CGBS with D=2.150 has the maximum deformation parameters(ε_(1,p)=0.05079,Δε_(v)=0.01990)due to the frictional slip effect caused by coarse aggregates.With increasing D,the failure modes of CGBSs are sequentially manifested as oblique shear failure,"Y-shaped"shear failure,and conjugate shear failure. 展开更多
关键词 cemented gangue backfill materials particle size distribution true triaxial compression test carbon nanotubes mechanical properties failure modes
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Novel Low-Carbon Optimal Operation Method for Flexible Distribution Network Based on Carbon Emission Flow
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作者 Chao Gao Kai Niu +3 位作者 Wenjing Chen Changwei Wang Yabin Chen Rui Qu 《Energy Engineering》 2025年第2期785-803,共19页
With the widespread implementation of distributed generation(DG)and the integration of soft open point(SOP)into the distribution network(DN),the latter is steadily transitioning into a flexible distribution network(FD... With the widespread implementation of distributed generation(DG)and the integration of soft open point(SOP)into the distribution network(DN),the latter is steadily transitioning into a flexible distribution network(FDN),the calculation of carbon flow distribution in FDN is more difficult.To this end,this study constructs a model for low-carbon optimal operations within the FDN on the basis of enhanced carbon emission flow(CEF).First,the carbon emission characteristics of FDNs are scrutinized and an improved method for calculating carbon flow within these networks is proposed.Subsequently,a model for optimizing low-carbon operations within FDNs is formulated based on the refined CEF,which merges the specificities of DG and intelligent SOP.Finally,this model is scrutinized using an upgraded IEEE 33-node distribution system,a comparative analysis of the cases reveals that when DG and SOP are operated in a coordinated manner in the FDN,with the cost of electricity generation was reduced by 40.63 percent and the cost of carbon emissions by 10.18 percent.The findings indicate that the judicious optimization of areas exhibiting higher carbon flow rates can effectively enhance the economic efficiency of DN operations and curtail the carbon emissions of the overall network. 展开更多
关键词 Flexible distribution network carbon emission flow distributed generation soft open points
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A Case Study on Garbage Code Redistribution Methods for Heart Failure at City Level by Two Approaches
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作者 Liqun Liu Zemin Cai +6 位作者 Xuewei Wang Chunping Wang Xiangyun Ma Xianfeng Meng Bofu Ning Ning Li Xia Wan 《Biomedical and Environmental Sciences》 2025年第1期119-125,共7页
Cause of death surveillance data is most important for developing effective health policies,whose quality is crucially affected by the accuracy of the underlying cause of death(UCOD)provided in death certificates.The ... Cause of death surveillance data is most important for developing effective health policies,whose quality is crucially affected by the accuracy of the underlying cause of death(UCOD)provided in death certificates.The World Health Organization(WHO)has clearly defined a UCOD as“the disease or injury which initiated the train of morbid events leading directly to death,or the circumstance of the accident or violence which produced the fatal injuries”[1]. 展开更多
关键词 INJURIES initiated distribution
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Some Eigenvalue Properties of Third-order Boundary Value Problems with Distributional Potentials
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作者 Hai-yan ZHANG Ji-jun AO 《Acta Mathematicae Applicatae Sinica》 2025年第1期179-199,共21页
Several eigenvalue properties of the third-order boundary value problems with distributional potentials are investigated.Firstly,we prove that the operators associated with the problems are self-adjoint and the corres... Several eigenvalue properties of the third-order boundary value problems with distributional potentials are investigated.Firstly,we prove that the operators associated with the problems are self-adjoint and the corresponding eigenvalues are real.Next,the continuity and differential properties of the eigenvalues of the problems are given,especially we find the differential expressions for the boundary conditions,the coefficient functions and the endpoints.Finally,we show a brief application to a kind of transmission boundary value problems of the problems studied here. 展开更多
关键词 third-order boundary value problems distributional potentials quasi-derivatives EIGENVALUES
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Numerical Simulation of Flow and Temperature Distribution in a Bottom-Blown Copper Bath
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作者 Teng Xia Xiaohui Zhang +4 位作者 Ding Ma Zhi Yang Xinting Tong Yutang Zhao Hua Wang 《Fluid Dynamics & Materials Processing》 2025年第1期121-140,共20页
Smelting with oxygen bottom blowing is one of the main methods used in the frame of copper pyrometallurgy.With this approach,feed materials and oxygen-enriched air are introduced in reversed order to enhance multiphas... Smelting with oxygen bottom blowing is one of the main methods used in the frame of copper pyrometallurgy.With this approach,feed materials and oxygen-enriched air are introduced in reversed order to enhance multiphaseflow within the furnace.Understanding the flow structure and temperature distribution in this setup is crucial foroptimizing production.In this study,gas-liquid interactions,and temperature profiles under varying air-injectionconditions are examined by means of numerical simulation for a 3.2 m×20 m furnace.The results indicate that thehigh-velocity regions are essentially distributed near the lance within the reaction region and the flue gas outlet,while low-velocity regions are located close to the furnace walls on both side of the reaction region.Dead regionsappear in the sedimentation region,with gas velocities surpassing those of the molten phase.As the injection rateincreases from 0.50 to 0.80 Nm3/s,the stabilization time of the average liquid surface velocity decreases from 2.6 sto 1.9 s,exhibiting a similar trend to the gas holdup.During stabilization,the average liquid surface velocity risesfrom 0.505 to 0.702 m/s.The average turbulent kinetic energy(TKE)of the fluid in the molten bath increases from0.095 to 0.162 m^(2)/s^(2).The proportion of the area distribution with TKE greater than 0.10 m^(2)/s^(2) and the gas holdupat steady state both rise with an increase in the injection quantity.The maximum splashing height of the melt growsfrom approximately 0.756 to 1.154 m,with the affected area expanding from 14.239 to 20.498 m^(2).Under differentworking conditions with varying injection quantities,the average temperature changes in melt zone and flue gaszone of the furnace are small.The temperature in the melt and in the flue-gas zone spans the interval 1200℃–1257℃,and 1073℃–1121℃,respectively.The temperature distribution of the melt and flue gas reveals a patterncharacterized by elevated temperatures in the reaction zone,gradually transitioning to lower temperatures in thesedimentation region. 展开更多
关键词 Copper smelting bottom-blown melting furnace flow characteristics temperature distribution numerical simulation
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Data driven prediction of fragment velocity distribution under explosive loading conditions
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作者 Donghwan Noh Piemaan Fazily +4 位作者 Songwon Seo Jaekun Lee Seungjae Seo Hoon Huh Jeong Whan Yoon 《Defence Technology(防务技术)》 2025年第1期109-119,共11页
This study presents a machine learning-based method for predicting fragment velocity distribution in warhead fragmentation under explosive loading condition.The fragment resultant velocities are correlated with key de... This study presents a machine learning-based method for predicting fragment velocity distribution in warhead fragmentation under explosive loading condition.The fragment resultant velocities are correlated with key design parameters including casing dimensions and detonation positions.The paper details the finite element analysis for fragmentation,the characterizations of the dynamic hardening and fracture models,the generation of comprehensive datasets,and the training of the ANN model.The results show the influence of casing dimensions on fragment velocity distributions,with the tendencies indicating increased resultant velocity with reduced thickness,increased length and diameter.The model's predictive capability is demonstrated through the accurate predictions for both training and testing datasets,showing its potential for the real-time prediction of fragmentation performance. 展开更多
关键词 Data driven prediction Dynamic fracture model Dynamic hardening model FRAGMENTATION Fragment velocity distribution High strain rate Machine learning
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First proof-of-principle experiment with the post-accelerated isotope separator on-line beam at BRIF:measurement of the angular distribution of ^(23)Na+^(40)Ca elastic scattering 被引量:13
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作者 Wei Nan Bing Guo +34 位作者 Cheng-Jian Lin Lei Yang Dong-Xi Wang Yang-Ping Shen Bing Tang Bao-Qun Cui Tao Ge Yin-Long Lyu Hui-Ming Jia Yun-Ju Li Chen Chen Li-Hua Chen Qi-Wen Fan Xin-Yue Li Gang Lian Jian-Cheng Liu Tian-Peng Luo Nan-Ru Ma Rui-Gang Ma Xie Ma Ying-Jun Ma Wei-Ke Nan Dan-Yang Pang You-Bao Wang Pei-Wei Wen Feng Yang Yong-Jin Yao Sheng Zeng Hao Zhang Fu-Peng Zhong Shan-Hao Zhong Zhi-Hong Li Tian-Jue Zhang Wei-Ping Liu BRIF Collaboration 《Nuclear Science and Techniques》 SCIE EI CAS CSCD 2021年第5期101-106,共6页
The reaction dynamics of exotic nuclei near the drip line is one of the main research topics of current interest.Elastic scattering is a useful probe for investigating the size and surface diffuseness of exotic nuclei... The reaction dynamics of exotic nuclei near the drip line is one of the main research topics of current interest.Elastic scattering is a useful probe for investigating the size and surface diffuseness of exotic nuclei.The development of rare isotope accelerators offers opportunities for such studies.To date,many relevant measurements have been performed at accelerators using the projectile fragmentation technique,while the measurements at accelerators using isotope separator on-line(ISOL)systems are still quite scarce.In this work,we present the first proof-of-principle experiment with a post-accelerated ISOL beam at the Beijing Radioactive Ion Beam Facility(BRIF)by measuring the angular distribution of elastic scattering for the stable nucleus^(23)Na from the doubly magic nucleus^(40)Ca at energies above the Coulomb barrier.The angular distribution measured by a silicon strip detector array in a scattering chamber using the ISOL beam at BRIF is in good agreement with that measured by the high-precision Q3 D magnetic spectrograph using the nonISOL beam at nearly the same energy.This work provides useful background for making BRIF a powerful tool for the investigation of the reaction dynamics of exotic nuclei. 展开更多
关键词 BRIF Exotic nuclei Elastic scattering Angular distribution
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Research on Distribution of Electromagnetic Environment around Substations and Optimization Layout of On-line Monitoring 被引量:1
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作者 Li Peiming Xiao Jun Wang Wenjin 《Meteorological and Environmental Research》 CAS 2019年第6期60-63,共4页
The characteristics and distribution law of electromagnetic environment around substations with different levels of voltage were studied,and the main influencing factors were discussed. Meanwhile,a scheme for locating... The characteristics and distribution law of electromagnetic environment around substations with different levels of voltage were studied,and the main influencing factors were discussed. Meanwhile,a scheme for locating monitoring points suitable for an on-line monitoring system of electromagnetic environment was proposed. 展开更多
关键词 on-line monitoring ELECTROMAGNETIC environment SUBSTATION Optimization layout
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ON THE MEAN VALUE AND VARIANCE OF DISTANCE DISTRIBUTION OF NON-LINEAR CODES IN GF(q)
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作者 Fu Fangwei Shen Shiyi(Department of Mathematics, Nankai University, Tianjin 300071) 《Journal of Electronics(China)》 1998年第1期58-62,共5页
This paper presents the lower bounds and upper bounds for the mean value and variance of distance distribution of non-linear codes in GF(q). By presenting several examples, it is shown that these bounds could be achie... This paper presents the lower bounds and upper bounds for the mean value and variance of distance distribution of non-linear codes in GF(q). By presenting several examples, it is shown that these bounds could be achieved. 展开更多
关键词 CODING theory DISTANCE distribution Althofer-Sillke INEQUALITY MacWilliams-Delsarte IDENTITY
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On-Line Independent Tap-Changing of Each Feeder Supplied by a Low Voltage Distribution Transformer
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作者 David Johnston 《Journal of Power and Energy Engineering》 2014年第4期388-394,共7页
An on-line tap-changing circuit was developed for use with low voltage transformers (10 kV/380 V, or equivalent), in which the tap positions could be set independently for each low voltage feeder. This allows for poss... An on-line tap-changing circuit was developed for use with low voltage transformers (10 kV/380 V, or equivalent), in which the tap positions could be set independently for each low voltage feeder. This allows for possible variation in loads and distributed generation between different feeders fed from a given transformer, allowing the line voltages to be kept within limits on all feeders. A combination of computer simulation and practical experiments was used. A model constructed in Excel gave preliminary results, which was used to specify a more detailed model in Matlab? Simulink. A small-scale 220/380 V distribution network was constructed, with currents limited to 5 A per phase. Finally, a rotary switch was constructed, suitable for currents up to 500 A, which would be required for a full-scale low voltage distribution network. The results showed that the voltage could be kept within limits, even with a large difference in load and distributed generation from one feeder to another. 展开更多
关键词 Tap-Changing on-line Feeders INDEPENDENT
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Effect of Temperature on the Molecular Weight Distribution in the Different Ranks of Coal during the On-Line Investigation of Coal Pyrolysis Gas Using Direct Photoionization Mass Spectroscopy
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作者 Makhosazana Mthembu Ralf Zimmermann +1 位作者 Thorsten Streibel Martin Sklorz 《International Journal of Clean Coal and Energy》 2015年第4期69-80,共12页
Coal pyrolysis gas from different ranks of coal was monitored on real time basis using photoionization mass spectroscopy. The molecular weight distribution of different products as a function of temperature from vario... Coal pyrolysis gas from different ranks of coal was monitored on real time basis using photoionization mass spectroscopy. The molecular weight distribution of different products as a function of temperature from various coal ranks studied was observed. It was noted that the release of different classes of compounds like phenols, alkenes, alkylated aromatics and aromatic skeletons was temperature dependent. For all the coal ranks at lower temperatures phenols were the main component, with alkenes and alkylated aromatics at slight higher temperatures and aromatic skeletons were released at the highest temperatures studied. 展开更多
关键词 COAL RANKS PHOTOIONIZATION Temperature Effect Molecular WEIGHT distribution COAL PYROLYSIS Gas
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Probability Distribution and Their Non-linear Relationship between Node Degree and Clustering Coefficient of Aviation Network of China Based on Complex Network
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作者 Cheng Xiangjun Yu Aihui Chen Xumei 《Journal of Traffic and Transportation Engineering》 2020年第2期55-62,共8页
In order to reveal the complex network feature of aviation network of China,probability distribution of node degree and clustering coefficient of aviation network of China was researched according to statistics data o... In order to reveal the complex network feature of aviation network of China,probability distribution of node degree and clustering coefficient of aviation network of China was researched according to statistics data of civil aviation of China.It was verified that node degree had power function probability distribution.Clustering coefficient of nodes with exponential function probability distribution was discovered.It was found that node degree and clustering coefficient had single peak nonlinear relationship.At the left side of the peak,there is no certain relationship between them.At the right side of the peak,clustering coefficient became smaller with the rise of node degree and there was negative exponential function relationship between them by regression analysis. 展开更多
关键词 Aviation network of China complex network feature probability distribution regression analysis curve fitting
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Assessing Micro-generation's and Non-linear Loads' Impact in the Power Quality of Low Voltage Distribution Networks
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作者 Paulo Bonifacio Susana Viana +1 位作者 Luis Rodrigues Ana Estanqueiro 《Journal of Energy and Power Engineering》 2013年第12期2321-2335,共15页
Distribution networks face an increasing penetration of solar PV (photovoltaic) and small WTG (wind turbine generator) as well as other forms of micro-generation. To this scenario, one must add the dissemination o... Distribution networks face an increasing penetration of solar PV (photovoltaic) and small WTG (wind turbine generator) as well as other forms of micro-generation. To this scenario, one must add the dissemination of non-linear loads such as EV (electric vehicles). There is something in common between those loads and sources: the extensive use of power electronic converters with commutated switches. These devices may be a source of medium-to-high frequency harmonic distortion and their impact on the local distribution grid must be carefully assessed in order to evaluate their negative impacts on the network, on the existing conventional loads and also on other active devices. In this paper, methodologies to characterize effects such as: harmonics, network unbalances, damaging power line resonance conditions, and over/under voltages are described and applied to a real local grid configuration. 展开更多
关键词 MICRO-GENERATION distribution network power quality HARMONICS smart grid electric vehicle.
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VALUE DISTRIBUTION OF MEROMORPHIC SOLUTIONS OF CERTAIN NON-LINEAR DIFFERENCE EQUATIONS
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作者 Minfeng CHEN Zongsheng GAO Jilong ZHANG 《Acta Mathematica Scientia》 SCIE CSCD 2019年第4期1173-1184,共12页
In this article, we consider the non-linear difference equation(f(z + 1)f(z)-1)(f(z)f(z-1)-1) =P(z, f(z))/Q(z, f(z)),where P(z, f(z)) and Q(z, f(z)) are relatively prime polynomials in f(z) with rational coefficients.... In this article, we consider the non-linear difference equation(f(z + 1)f(z)-1)(f(z)f(z-1)-1) =P(z, f(z))/Q(z, f(z)),where P(z, f(z)) and Q(z, f(z)) are relatively prime polynomials in f(z) with rational coefficients. For the above equation, the order of growth, the exponents of convergence of zeros and poles of its transcendental meromorphic solution f(z), and the exponents of convergence of poles of difference △f(z) and divided difference △f(z)/f(z)are estimated. Furthermore, we study the forms of rational solutions of the above equation. 展开更多
关键词 Non-lineAR DIFFERENCE equation MEROMORPHIC SOLUTION RATIONAL SOLUTION value dist ribution
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Molecular Weight Distribution of Dissolved Organic Matter in Lake Hongfeng Determined by High Performance Size Exclusion Chromatography (HPSEC) With On-Line UV-Vis Absorbance and Fluorescence Detection 被引量:3
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作者 岳兰秀 吴丰昌 +3 位作者 刘丛强 黎文 王静 梅毅 《Chinese Journal Of Geochemistry》 EI CAS 2004年第3期275-283,共9页
The molecular weight distribution (MWD) of dissolved organic matter (DOM) in lake waters from Lake Hongfeng was examined using high performance size exclusion chromatography (HPSEC) with UV-vis absorbance and fluoresc... The molecular weight distribution (MWD) of dissolved organic matter (DOM) in lake waters from Lake Hongfeng was examined using high performance size exclusion chromatography (HPSEC) with UV-vis absorbance and fluorescence detection. The elution curves obtained by absorbance and fluorescence techniques expressed similar patterns, with the exception of diminishing of large fraction and the peaks behind several seconds in fluorescence chromatograms. According to its molecular weight (MW), DOM in water samples is divided into several fractions: large ({>3.5} kDa); medium-large ({3.5}-{2.0} kDa); medium ({2.0}-{1.0} kDa) and small ({<1.0} kDa). The average molecular weight was calculated using the elution curve detected by UV-vis absorbance and fluorescence detection techniques. The results showed that the weight-average molecular weight (Mw) and number-average molecular weight (Mn) calculated by UV-vis absorbance techniques range from 1750 to 2050 Dalton and from 1450 to 1850 Dalton, respectively. And the Mw and Mn obtained by fluorescence detection are lower by 50 to 400 Dalton. As a reference, the molecular weight of Fluka humic acid (FHA) is larger than that of water samples by about 200 Dalton. The average molecular weight of DOM for water samples collected in March and July was compared. The results revealed that the molecular weight is lower for water samples obtained in July than that obtained in March, indicating the ambient environment has an influence on the molecular weight, including photo-degradation and biological activity. 展开更多
关键词 液化有机物 分子量 平均数 吸收比 荧光性 聚合化合物 湖水生物化学
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Spatial distribution of shallow landslides caused by Typhoon Lekima in 2019 in Zhejiang Province, China 被引量:2
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作者 CUI Yulong YANG Liu +1 位作者 XU Chong ZHENG Jun 《Journal of Mountain Science》 SCIE CSCD 2024年第5期1564-1580,共17页
In recent years, the coastal region of Southeast China has witnessed a significant increase in the frequency and intensity of extreme rainfall events associated with landfalling typhoons. The hilly and mountainous ter... In recent years, the coastal region of Southeast China has witnessed a significant increase in the frequency and intensity of extreme rainfall events associated with landfalling typhoons. The hilly and mountainous terrain of this area, combined with rapid rainfall accumulation, has led to a surge in flash floods and severe geological hazards. On August 10, 2019, Typhoon Lekima made landfall in Zhejiang Province, China, and its torrential rainfall triggered extensive landslides, resulting in substantial damage and economic losses. Utilizing high-resolution satellite images, we compiled a landslide inventory of the affected area, which comprises a total of 2,774 rainfallinduced landslides over an area of 2965 km2. The majority of these landslides were small to mediumsized and exhibited elongated, clustered patterns. Some landslides displayed characteristics of high-level initiation, obstructing or partially blocking rivers, leading to the formation of debris dams. We used the inventory to analyze the distribution pattern of the landslides and their relationship with topographical, geological, and hydrological factors. The results showed that landslide abundance was closely related to elevation, slope angle, faults, and road density. The landslides were predominantly located in hilly and low mountainous areas, with elevations ranging from 150 to 300 m, slopes of 20 to 30 degrees, and a NE-SE aspect. Notably, we observed the highest Landslide Number Density(LND) and Landslide Area Percentage(LAP) in the rhyolite region. Landslides were concentrated within approximately 4 km on either side of fault zones, with their size and frequency negatively correlated with distances to faults, roads, and river systems. Furthermore, under the influence of typhoons, regions with denser vegetation cover exhibited higher landslide density, reaching maximum values in shrubland areas. In areas experiencing significantly increased concentrated rainfall, landslide density also showed a corresponding rise. In terms of spatial distribution, the rainfall-triggered landslides primarily occurred in the northeastern part of the study area, particularly in regions characterized by complex topography such as Shanzao Village in Yantan Town, Xixia Township, and Shangzhang Township. The research findings offer crucial data on the rainfallinduced landslides triggered by Typhoon Lekima, shedding light on their spatial distribution patterns. These findings provide valuable references for mitigating risks and planning reconstruction in typhoon-affected area. 展开更多
关键词 Typhoon rainfall Landslide characteristics Spatial distribution Southeast coastal region
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Red cell distribution width-to-albumin ratio is a simple promising prognostic marker in acute cholangitis requiring biliary drainage 被引量:3
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作者 Fatih Acehan Hüseyin Camli +4 位作者 Cagdas Kalkan Mesut Tez Burak Furkan Demir Emin Altiparmak Ihsan Ates 《Hepatobiliary & Pancreatic Diseases International》 SCIE CAS CSCD 2024年第5期487-494,共8页
Background: It is crucial to assess the severity of acute cholangitis(AC). There are currently several prognostic markers. However, the accuracies of these markers are not satisfied. The present study aimed to investi... Background: It is crucial to assess the severity of acute cholangitis(AC). There are currently several prognostic markers. However, the accuracies of these markers are not satisfied. The present study aimed to investigate the predictive value of the red cell distribution width(RDW)-to-albumin ratio(RAR) for the prognosis of AC. Methods: We retrospectively evaluated consecutive patients diagnosed with AC between May 2019 and March 2022. RAR was calculated, and its predictive ability for in-hospital mortality, intensive care unit(ICU) admission, bacteremia, and the length of hospitalization were analyzed. Results: Out of 438 patients, 34(7.8%) died. Multivariate analysis showed that malignant etiology [odds ratio(OR) = 4.816, 95% confidence interval(CI): 1.936-11.980], creatinine(OR = 1.649, 95% CI: 1.095-2.484), and RAR(OR = 2.064, 95% CI: 1.494-2.851) were independent risk factors for mortality. When adjusted for relevant covariates, including age, sex, malignant etiology, Tokyo severity grading(TSG), Charlson comorbidity index, and creatinine, RAR significantly predicted mortality(adjusted OR = 1.833, 95% CI: 1.280-2.624). When the cut-off of RAR was set to 3.8, its sensitivity and specificity for mortality were 94.1% and 56.7%, respectively. Patients with an RAR of > 3.8 had a 20.9-fold(OR = 20.9, 95% CI: 4.9-88.6) greater risk of mortality than the remaining patients. The area under the curve value of RAR for mortality was 0.835(95% CI: 0.770-0.901), which was significantly higher than that of TSG and the other prognostic markers, such as C-reactive protein-to-albumin ratio, and procalcitonin-to-albumin ratio. Lastly, RAR was not inferior to TSG in predicting ICU admission, bacteremia, and the length of hospitalization. Conclusions: RAR successfully predicted the in-hospital mortality, ICU admission, bacteremia, and the length of hospitalization of patients with AC, especially in-hospital mortality. RAR is a promising marker that is more convenient than TSG and other prognostic markers for predicting the prognosis of patients with AC. 展开更多
关键词 Acute cholangitis ALBUMIN Biliary drainage MORTALITY Red blood cell distribution width-to-albumin ratio
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