期刊文献+
共找到289,877篇文章
< 1 2 250 >
每页显示 20 50 100
Efficient and Stable Perovskite Solar Cells and Modules Enabled by Tailoring Additive Distribution According to the Film Growth Dynamics
1
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
在线阅读 下载PDF
Differential distribution of PINK1 and Parkin in the primate brain implies distinct roles
2
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
在线阅读 下载PDF
Distributed stochastic model predictive control for energy dispatch with distributionally robust optimization
3
作者 Mengting LIN Bin LI C.C.ECATI 《Applied Mathematics and Mechanics(English Edition)》 2025年第2期323-340,共18页
A chance-constrained energy dispatch model based on the distributed stochastic model predictive control(DSMPC)approach for an islanded multi-microgrid system is proposed.An ambiguity set considering the inherent uncer... A chance-constrained energy dispatch model based on the distributed stochastic model predictive control(DSMPC)approach for an islanded multi-microgrid system is proposed.An ambiguity set considering the inherent uncertainties of renewable energy sources(RESs)is constructed without requiring the full distribution knowledge of the uncertainties.The power balance chance constraint is reformulated within the framework of the distributionally robust optimization(DRO)approach.With the exchange of information and energy flow,each microgrid can achieve its local supply-demand balance.Furthermore,the closed-loop stability and recursive feasibility of the proposed algorithm are proved.The comparative results with other DSMPC methods show that a trade-off between robustness and economy can be achieved. 展开更多
关键词 distributed stochastic model predictive control(DSMPC) distributionally robust optimization(DRO) islanded multi-microgrid energy dispatch strategy
在线阅读 下载PDF
Optimal Planning of Multiple PV-DG in Radial Distribution Systems Using Loss Sensitivity Analysis and Genetic Algorithm
4
作者 A. Elkholy 《Journal of Power and Energy Engineering》 2025年第2期1-22,共22页
This paper introduces an optimized planning approach for integrating photovoltaic as distributed generation (PV-DG) into the radial distribution power systems, utilizing exhaustive load flow (ELF), loss sensitivity fa... This paper introduces an optimized planning approach for integrating photovoltaic as distributed generation (PV-DG) into the radial distribution power systems, utilizing exhaustive load flow (ELF), loss sensitivity factor (LSF), genetic algorithms (GA) methods, and numerical method based on LSF. The methodology aims to determine the optimal allocation and sizing of multiple PV-DG to minimize power loss through time series power flow analysis. An approach utilizing continuous sensitivity analysis is developed and inherently leverages power flow and loss equations to compute LSF of all buses in the system towards employing a dynamic PV-DG model for more accurate results. The algorithm uses a numerical grid search method to optimize PV-DG placement in a power distribution system, focusing on minimizing system losses. It combines iterative analysis, sensitivity assessment, and comprehensive visualization to identify and present the optimal PV-DG configurations. The present-ed algorithms are verified through co-simulation framework combining MATLAB and OpenDSS to carry out analysis for 12-bus radial distribution test system. The proposed numerical method is compared with other algorithms, such as ELF, LSF methods, and Genetic Algorithms (GA). Results show that the proposed numerical method performs well in comparison with LSF and ELF solutions. 展开更多
关键词 Photovoltaic Systems distributed Generation Multiple Allocation and Sizing Power Losses Radial distribution System Genetic Algorithm
在线阅读 下载PDF
Pretreatment red blood cell distribution width as a predictive marker for postoperative complications after laparoscopic pancreatoduodenectomy
5
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
在线阅读 下载PDF
A Note on Beta Distribution Goodness of Fit
6
作者 Mezbahur Rahman Md Iftekhar Amin Mahmudul Hasan 《Open Journal of Statistics》 2025年第1期35-40,共6页
The Beta Distribution is widely used in engineering and industrial applications. Goodness-of-fit procedures are revisited. Shapiro-Francia statistic is implemented in Beta distribution. A comparative study between the... The Beta Distribution is widely used in engineering and industrial applications. Goodness-of-fit procedures are revisited. Shapiro-Francia statistic is implemented in Beta distribution. A comparative study between the Anderson-Darling, Kolmogorov-Smirnov, Shapiro-Francia, and Chi-square goodness-of-fit test in testing for Beta distribution is performed using simulation. 展开更多
关键词 Anderson-Darling Test Beta-Normal Composite distribution Kolmogorov-Smirnov Test Shapiro-Francia Test Truncated Normal distribution
在线阅读 下载PDF
Multi-Stage Voltage Control Optimization Strategy for Distribution Networks Considering Active-Reactive Co-Regulation of Electric Vehicles
7
作者 Shukang Lyu Fei Zeng +3 位作者 Huachun Han Huiyu Miao Yi Pan Xiaodong Yuan 《Energy Engineering》 EI 2025年第1期221-242,共22页
The high proportion of uncertain distributed power sources and the access to large-scale random electric vehicle(EV)charging resources further aggravate the voltage fluctuation of the distribution network,and the exis... The high proportion of uncertain distributed power sources and the access to large-scale random electric vehicle(EV)charging resources further aggravate the voltage fluctuation of the distribution network,and the existing research has not deeply explored the EV active-reactive synergistic regulating characteristics,and failed to realize themulti-timescale synergistic control with other regulatingmeans,For this reason,this paper proposes amultilevel linkage coordinated optimization strategy to reduce the voltage deviation of the distribution network.Firstly,a capacitor bank reactive power compensation voltage control model and a distributed photovoltaic(PV)activereactive power regulationmodel are established.Additionally,an external characteristicmodel of EVactive-reactive power regulation is developed considering the four-quadrant operational characteristics of the EVcharger.Amultiobjective optimization model of the distribution network is then constructed considering the time-series coupling constraints of multiple types of voltage regulators.A multi-timescale control strategy is proposed by considering the impact of voltage regulators on active-reactive EV energy consumption and PV energy consumption.Then,a four-stage voltage control optimization strategy is proposed for various types of voltage regulators with multiple time scales.Themulti-objective optimization is solved with the improvedDrosophila algorithmto realize the power fluctuation control of the distribution network and themulti-stage voltage control optimization.Simulation results validate that the proposed voltage control optimization strategy achieves the coordinated control of decentralized voltage control resources in the distribution network.It effectively reduces the voltage deviation of the distribution network while ensuring the energy demand of EV users and enhancing the stability and economic efficiency of the distribution network. 展开更多
关键词 Electric vehicle(EV) distribution network multi-stage optimization active-reactive power regulation voltage control
在线阅读 下载PDF
On the Distributional Forecasting of UK Economic Growth with Generalised Additive Models for Location Scale and Shape (GAMLSS)
8
作者 Jonathan Iworiso Nera Ebenezer Mansi +1 位作者 Aruoriwo Ocharive Shepherd Fubara 《Journal of Data Analysis and Information Processing》 2025年第1期1-24,共24页
The UK’s economic growth has witnessed instability over these years. While some sectors recorded positive performances, some recorded negative performances, and these unstable economic performances led to technical r... The UK’s economic growth has witnessed instability over these years. While some sectors recorded positive performances, some recorded negative performances, and these unstable economic performances led to technical recession for the third and fourth quarters of the year 2023. This study assessed the efficacy of the Generalised Additive Model for Location, Scale and Shape (GAMLSS) as a flexible distributional regression with smoothing additive terms in forecasting the UK economic growth in-sample and out-of-sample over the conventional Autoregressive Distributed Lag (ARDL) and Error Correction Model (ECM). The aim was to investigate the effectiveness and efficiency of GAMLSS models using a machine learning framework over the conventional time series econometric models by a rolling window. It is quantitative research which adopts a dataset obtained from the Office for National Statistics, covering 105 monthly observations of major economic indicators in the UK from January 2015 to September 2023. It consists of eleven variables, which include economic growth (Econ), consumer price index (CPI), inflation (Infl), manufacturing (Manuf), electricity and gas (ElGas), construction (Const), industries (Ind), wholesale and retail (WRet), real estate (REst), education (Edu) and health (Health). All computations and graphics in this study are obtained using R software version 4.4.1. The study revealed that GAMLSS models demonstrate superior outperformance in forecast accuracy over the ARDL and ECM models. Unlike other models used in the literature, the GAMLSS models were able to forecast both the future economic growth and the future distribution of the growth, thereby contributing to the empirical literature. The study identified manufacturing, electricity and gas, construction, industries, wholesale and retail, real estate, education, and health as key drivers of UK economic growth. 展开更多
关键词 distributional Forecasting Out-of-Sample GAMLSS ML Model Complexity
在线阅读 下载PDF
Effects of aggregate size distribution and carbon nanotubes on the mechanical properties of cemented gangue backfill samples under true triaxial compression
9
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
在线阅读 下载PDF
Reconfiguration and Optimal Positioning of Multiple-Point Capacitors in a High-Voltage Distribution Network Using the NSGAII
10
作者 Arouna Oloulade Richard Gilles Agbokpanzo +6 位作者 Maurel Richy Aza-Gnandji Hassane Ousseyni Ibrahim Moussa Gonda Eméric Tokoudagba Juliano Sétondji François-Xavier Fifatin Adolphe Moukengue Imano 《Open Journal of Applied Sciences》 2025年第2期501-516,共16页
The distribution networks sometimes suffer from excessive losses and voltage violations in densely populated areas. The aim of the present study is to improve the performance of a distribution network by successively ... The distribution networks sometimes suffer from excessive losses and voltage violations in densely populated areas. The aim of the present study is to improve the performance of a distribution network by successively applying mono-capacitor positioning, multiple positioning and reconfiguration processes using GA-based algorithms implemented in a Matlab environment. From the diagnostic study of this network, it was observed that a minimum voltage of 0.90 pu induces a voltage deviation of 5.26%, followed by active and reactive losses of 425.08 kW and 435.09 kVAR, respectively. Single placement with the NSGAII resulted in the placement of a 3000 kVAR capacitor at node 128, which proved to be the invariably neuralgic point. Multiple placements resulted in a 21.55% reduction in losses and a 0.74% regression in voltage profile performance. After topology optimization, the loss profile improved by 65.08% and the voltage profile improved by 1.05%. Genetic algorithms are efficient and effective tools for improving the performance of distribution networks, whose degradation is often dynamic due to the natural variability of loads. 展开更多
关键词 RECONFIGURATION Capacitor Bank NSGA II Dynamic Network Degradation distribution Network Reliability
在线阅读 下载PDF
Distribution of Human Papillomavirus (HPV) Infection in Women of Appropriate Age in Beiliu City and Recommendations for Public Health Intervention
11
作者 Haiquan Li Jinhua Wei Huan Zhao 《Natural Science》 2025年第1期1-6,共6页
Objective: This study aims to analyze the distribution of positive human papillomavirus (HPV) infections among women of appropriate age in Beiliu City during cervical cancer screening in 2024, providing data support f... Objective: This study aims to analyze the distribution of positive human papillomavirus (HPV) infections among women of appropriate age in Beiliu City during cervical cancer screening in 2024, providing data support for subsequent public health interventions. Methods: A retrospective analysis was conducted on the HPV test results from January 1, 2024, to November 30, 2024, at Beiliu Maternal and Child Health Hospital. We statistically analyzed the positive rates of different HPV genotypes and the co-infection status of multiple genotypes. Results: A total of 7558 individuals were tested, with 1103 positive cases identified, resulting in a positivity rate of 14.59%. Among these, HPV type 52 had the highest positive rate, accounting for 18.47%. The co-infection analysis showed that there were 788 cases with single genotype positivity, 236 with double genotype positivity, and 58 with triple genotype positivity, while cases with multiple genotypes simultaneously positive were relatively rare. Conclusion: The HPV infection rate among women of appropriate age in Beiliu City is relatively high, especially for high-risk HPV types. To reduce the future incidence of cervical cancer, it is recommended to enhance health education and vaccination efforts for this population. 展开更多
关键词 HPV Infection Cervical Cancer Screening Positive distribution Women of Appropriate Age Public Health
在线阅读 下载PDF
Novel Low-Carbon Optimal Operation Method for Flexible Distribution Network Based on Carbon Emission Flow
12
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
在线阅读 下载PDF
Revealing Light-Induced Charge Density Wave Melting and Carrier Redistribution in 1T-TiSe_(2)
13
作者 Wanying Chen Haoyuan Zhong +6 位作者 Changhua Bao Fei Wang Xuanxi Cai Chenxia Yun Hao Teng Zhiyi Wei Shuyun Zhou 《Chinese Physics Letters》 2025年第1期123-133,共11页
Capturing ultrafast dynamics over a large momentum space is critical for revealing the relationship between the electronic and structural modulations in quantum materials.Here,by performing time-and angle-resolved pho... Capturing ultrafast dynamics over a large momentum space is critical for revealing the relationship between the electronic and structural modulations in quantum materials.Here,by performing time-and angle-resolved photoemission spectroscopy measurements at the Synergetic Extreme Condition User Facility(SECUF)equipped with an extreme ultraviolet light source,we reveal the ultrafast dynamics of a charge-density wave(CDW)material,1T-TiSe_(2),upon photoexcitation.Pump-induced CDW melting is revealed from two aspects:gap closing of the CDW at the Brillouin zone(BZ)center and weakening of the CDW folded band at the BZ boundary.By comparing the transient electronic structure and spectral weight over a large momentum space,we further reveal the carrier redistribution involving the excitation of electrons from theГpoint to the M point.This study provides a comprehensive picture of the physics and ultrafast dynamics of a CDW material across the entire BZ. 展开更多
关键词 MOMENTUM equipped distribution
在线阅读 下载PDF
A Case Study on Garbage Code Redistribution Methods for Heart Failure at City Level by Two Approaches
14
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
在线阅读 下载PDF
Vertical distribution of microplastics in coastal sediments of Xuwen Coral Reef National Nature Reserve,China
15
作者 Mayakrishnan MACHENDIRANATHAN Guangzhe JIN +5 位作者 Huaxia HUANG Tingbang LIANG Zongxuan LIN Huiying LIN Lingling XIE Fajin CHEN 《Journal of Oceanology and Limnology》 2025年第2期422-432,共11页
Plastic pollution and microplastics in sediments are a growing concern for marine ecosystems worldwide.We examined the vertical distribution and properties of microplastics in beach sediments of Xuwen Coral Reef Natio... Plastic pollution and microplastics in sediments are a growing concern for marine ecosystems worldwide.We examined the vertical distribution and properties of microplastics in beach sediments of Xuwen Coral Reef National Nature Reserve,in Leizhou Peninsula,Zhanjiang,China.Sediment samples were taken in seven locations at 5-cm intervals from the surface to a depth of 30 cm.The vertical distribution of microplastic particles ranged from 0 to 1340 particles per kg on average of 119.05particles per kg.The most prevalent material was fibers(76%),followed by film(12%),fragments(11.2%),and foam(0.8%).The microplastics in size of 1-2 mm constituted the largest percentage(40%)of the total,followed by those in size of<1 mm(26.4%),2-3 mm(21.2%),3-4 mm(9.6%),and 4-5 mm(2.81%).Site S1 observed maximum sizes between 1 and 2 mm,S2 reported higher availability of microplastics with sizes ranging from 0.3 to 1 mm.Six different types of polymers were identified in the investigation,and mostly were polyethylene(PE)and polypropylene(PP).In general,the observation of microplastics in deeper sediments indicates that they have the ability to last for prolonged periods in the marine environment,which may present long-term hazards to benthic creatures.In conclusion,the discovery of microplastics in deep layers of coastal sediments highlights the necessity of minimizing plastic waste and enhancing management strategies to safeguard marine environments. 展开更多
关键词 coral beach vertical distribution microplastic SEDIMENT Xuwen
在线阅读 下载PDF
Effect of pseudo-random number on the security of quantum key distribution protocol
16
作者 Xiao-Liang Yang Yu-Qing Li Hong-Wei Li 《Chinese Physics B》 2025年第2期41-46,共6页
In the process of quantum key distribution(QKD), the communicating parties need to randomly determine quantum states and measurement bases. To ensure the security of key distribution, we aim to use true random sequenc... In the process of quantum key distribution(QKD), the communicating parties need to randomly determine quantum states and measurement bases. To ensure the security of key distribution, we aim to use true random sequences generated by true random number generators as the source of randomness. In practical systems, due to the difficulty of obtaining true random numbers, pseudo-random number generators are used instead. Although the random numbers generated by pseudorandom number generators are statistically random, meeting the requirements of uniform distribution and independence,they rely on an initial seed to generate corresponding pseudo-random sequences. Attackers may predict future elements from the initial elements of the random sequence, posing a security risk to quantum key distribution. This paper analyzes the problems existing in current pseudo-random number generators and proposes corresponding attack methods and applicable scenarios based on the vulnerabilities in the pseudo-random sequence generation process. Under certain conditions, it is possible to obtain the keys of the communicating parties with very low error rates, thus effectively attacking the quantum key system. This paper presents new requirements for the use of random numbers in quantum key systems, which can effectively guide the security evaluation of quantum key distribution protocols. 展开更多
关键词 quantum key distribution PSEUDO-RANDOM SECURITY
在线阅读 下载PDF
Spatial and Temporal Distribution of Metal Elements in the Rivers of Northern Jiangsu Province
17
作者 YUAN Liping LIU Qian +3 位作者 JIAN Huimin MI Tiezhu YANG Fuxia YAO Qingzhen 《Journal of Ocean University of China》 2025年第1期157-168,共12页
The concentrations of V,Cr,Mn,Fe,Co,Ni,Cu,Zn,As,Mo,Cd,and Pb were determined in Doulonggang River,Xinyanggang River,Huangshagang River,Sheyanghe River,Guangaizongqu River,and Linhonghe River at the North of Jiangsu Pr... The concentrations of V,Cr,Mn,Fe,Co,Ni,Cu,Zn,As,Mo,Cd,and Pb were determined in Doulonggang River,Xinyanggang River,Huangshagang River,Sheyanghe River,Guangaizongqu River,and Linhonghe River at the North of Jiangsu Province in 2019.The annual average concentrations of V,Cr,Mn,Fe,Co,Ni,Cu,Zn,As,Mo,Cd and Pb in the six rivers were 2.20,1.22,4.53,21.9,0.13,2.79,1.77,4.00,2.97,3.87,0.01,0.19μg L^(-1)respectively.The highest concentration of most trace metals were found in Guangaizongqu River and Linhonghe River,and the lowest concentration were found in Xinyanggang River and Huangshagang River.The principal component analysis(PCA)resulted of two factors together explained 91.2%of the variance with>1initial eigenvalue,indicating that both natural and anthropogenic activities were contributing factors as the source of metal abundance in rivers of northern Jiangsu Province.The first major component represented the influence of anthropogenic activities,including industry and agriculture,with a contribution rate of 54.1%,affected Cr,Fe,Cu,Zn,Mo,Cd and Pb.The second(such as V,Mn,Co,Ni,As)was a mixed source,including the natural processes such as precipitation,erosion and weathering and anthropogenic action like industry and agriculture,with a contribution rate of 37.1%.Seasonal variations in trace metal concentrations were influenced by temperature,salinity,water discharge,and input of external pollutants.The highest concentrations were found in wet season and were strongly influenced by rainfall and seasonal industrial and agricultural activities. 展开更多
关键词 trace metal distribution RIVERS northern Jiangsu Province
在线阅读 下载PDF
A ComputationalModeling on Flow Bifurcation and Energy Distribution through a Loosely Bent Rectangular Duct with Vortex Structure
18
作者 Rabindra NathMondal Giulio Lorenzini +1 位作者 Sidhartha Bhowmick Sreedham Chandra Adhikari 《Frontiers in Heat and Mass Transfer》 2025年第1期249-278,共30页
The present study investigates the non-isothermal flow and energy distribution through a loosely bent rectangular duct using a spectral-based numerical approach over a wide range of the Dean number 0<Dn≤3000.Unlik... The present study investigates the non-isothermal flow and energy distribution through a loosely bent rectangular duct using a spectral-based numerical approach over a wide range of the Dean number 0<Dn≤3000.Unlike previous research,this work offers novel insights by conducting a grid-point-specific velocity analysis and identifying new bifurcation structures.The study reveals how centrifugal and buoyancy forces interact to produce steady,periodic,and chaotic flow regimes significantly influencing heat transfer performance.The Newton-Raphson method is employed to explore four asymmetric steady branches,with vortex solutions ranging from 2-to 12 vortices.Unsteady flow characteristics are analyzed exquisitely by performing time-advancement of the solutions and the flow regimes are shown as a percentage of total flow with longitudinal vortex generation.Axial flow,secondary flow,and temperature profiles have been depicted in accordance with Dn to wander the flow pattern,and it is predicted that the time-dependent flow(TDF)consists of asymmetric 2-to 10-vortex solutions.The significant findings of this study include the axial displacement of the circulations due to the influence of the time-varying temperature dispersal applied along the wall.Chaotic flows,which dominate the higher Dean number range,are shown to enhance heat convection due to increased fluid mixing.A detailed comparison with prior research demonstrates the advantages of this approach,particularly in capturing complex non-linear behaviors.The findings of this study provide practical guidelines for optimizing duct designs to maximize heat transfer and suggest future research directions,such as using nanofluids or studying Magneto-hydrodynamics in the same configuration. 展开更多
关键词 Bending duct steady solutions time-advancement energy distribution VORTEX
在线阅读 下载PDF
Centralized-Distributed Scheduling Strategy of Distribution Network Based on Multi-Temporal Hierarchical Cooperative Game
19
作者 Guoqing Li Jianing Li +1 位作者 Kefei Yan Jing Bian 《Energy Engineering》 2025年第3期1113-1136,共24页
A centralized-distributed scheduling strategy for distribution networks based on multi-temporal and hierarchical cooperative game is proposed to address the issues of difficult operation control and energy optimizatio... A centralized-distributed scheduling strategy for distribution networks based on multi-temporal and hierarchical cooperative game is proposed to address the issues of difficult operation control and energy optimization interaction in distribution network transformer areas,as well as the problem of significant photovoltaic curtailment due to the inability to consume photovoltaic power locally.A scheduling architecture combiningmulti-temporal scales with a three-level decision-making hierarchy is established:the overall approach adopts a centralized-distributed method,analyzing the operational characteristics and interaction relationships of the distribution network center layer,cluster layer,and transformer area layer,providing a“spatial foundation”for subsequent optimization.The optimization process is divided into two stages on the temporal scale:in the first stage,based on forecasted electricity load and demand response characteristics,time-of-use electricity prices are utilized to formulate day-ahead optimization strategies;in the second stage,based on the charging and discharging characteristics of energy storage vehicles and multi-agent cooperative game relationships,rolling electricity prices and optimal interactive energy solutions are determined among clusters and transformer areas using the Nash bargaining theory.Finally,a distributed optimization algorithm using the bisection method is employed to solve the constructed model.Simulation results demonstrate that the proposed optimization strategy can facilitate photovoltaic consumption in the distribution network and enhance grid economy. 展开更多
关键词 Photovoltaic consumption distribution area optimal scheduling cooperative game
在线阅读 下载PDF
Improved reference-frame-independent quantum key distribution with intensity fluctuations
20
作者 Zi-Qi Chen Hao-Bing Sun +1 位作者 Ming-Shuo Sun Qin Wang 《Chinese Physics B》 2025年第2期48-52,共5页
Reference-frame-independent quantum key distribution(RFI-QKD) can avoid real-time calibration operation of reference frames and improve the efficiency of the communication process. However, due to imperfections of opt... Reference-frame-independent quantum key distribution(RFI-QKD) can avoid real-time calibration operation of reference frames and improve the efficiency of the communication process. However, due to imperfections of optical devices,there will inevitably exist intensity fluctuations in the source side of the QKD system, which will affect the final secure key rate. To reduce the influence of intensity fluctuations, an improved 3-intensity RFI-QKD scheme is proposed in this paper.After considering statistical fluctuations and implementing global parameter optimization, we conduct corresponding simulation analysis. The results show that our present work can present both higher key rate and a farther transmission distance than the standard method. 展开更多
关键词 quantum key distribution intensity fluctuations decoy-state method
在线阅读 下载PDF
上一页 1 2 250 下一页 到第
使用帮助 返回顶部