检索结果-南通市图书馆

Hydrodynamic characteristics and particle tracking of 90° lateral intakes at an inclined river slope

Water Science and Engineering 2024年第2期17卷 197-208页

作者： Wei He si-yuan feng Jian Zhang Hong-wu Tang Yang Xiao Sheng Chen Chun-sheng Liu College of Water Conservancy and Hydropower Engineering Hohai UniversityNanjing 210098China State Key Laboratory of Hydrology Water Resources and Hydraulic Engineering Hohai UniversityNanjing 210098China Collaborative Innovation Center on Water Safety and Water Science Hohai UniversityNanjing 210098China

Lateral intakes are common in *** pump effciency and sediment deposition are determined by the local hydrodynamic characteristics and mainstream division *** hydraulic characteristics of lateral withdrawal from inclined river slopes at different intake elevations should be ***,the division width exhibits significant vertical non-uniformity at an inclined river slope,which should be ***,a three-dimensional(3-D)hydrodynamic and particle-tracking model was developed with the Open Source Field Operation and Manipulation(Open FOAM),and the model was validated with physical model tests for 90°lateral withdrawal from an inclined side *** flow fields,withdrawal sources,and division widths were investigated with different intake bottom elevations,withdrawal discharges,and main channel *** study showed that under inclined side bank conditions,water entered the intake at an oblique angle,causing significant 3-D spiral flows in the intake rather than two-dimensional closed recirculation.A lower withdrawal discharge,a lower bottom elevation of the intake,or a higher main channel velocity could further strengthen this *** average division width and turbulent kinetic energy were smaller under inclined side bank conditions than under vertical bank *** a low intake bottom elevation,a low withdrawal discharge,or a high main channel velocity,the sources of lateral withdrawal were in similar ranges near the local inclined bank in the vertical *** inclined slope conditions,sediment deposition near the intake entrance could be reduced,compared to that under vertical slope *** results provide hydrodynamic and sediment references for engineering designs for natural rivers with inclined terrains.

关键词： Lateral withdrawal Hydrodynamic characteristics Particle tracking Inclined river slope Bottom elevation of intake OpenFOAM

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Adhesive Contact of Elastic Solids with Self-Affine Fractal Rough Surfaces

引用

Acta Mechanica Solida sinica 2024年第2期37卷 265-270页

作者： Xuan-Ming Liang Shi-Wen Chen si-He Wang Zhen-yuan Gong Jun feng Gang-feng Wang Department of Engineering Mechanics SVL and MMMLXi’an Jiaotong UniversityXi’an710049China OPPO Mobile Telecommunications Corporation Ltd. Dongguan523860China

The elastic adhesive contact of self-affine fractal rough surfaces against a rigid flat is simulated using the finite element method. An array of nonlinear springs, of which the force-separation law obeys the Lennard–Jones potential, is introduced to account for the interfacial adhesion. For fractal rough surfaces, the interfacial interaction is generally attractive for large mean gaps, but turns repulsive as the gap continuously shrinks. The interfacial interactions at the turning point corresponding to the spontaneous contact are shown for various surfaces. For relatively smooth surfaces, the probability density distributions of repulsion and attraction are nearly symmetric. However, for rougher surfaces, the simulation results suggest a uniform distribution for attraction but a monotonously decreasing distribution with a long tail for repulsion. The pull-off force rises with increasing ratio of the work of adhesion to the equilibrium distance, whereas decreases for solids with a higher elastic modulus and a larger surface roughness. The current study will be helpful for understanding the adhesion of various types of rough solids.

关键词： Fractal rough surfaces Adhesion Contact mechanics Lennard-Jones potential

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Coexistence of All-Order Topological States in a Three-Dimensional Phononic Topological Crystalline Insulator

引用

Research 2024年第2期2023卷 511-518页

作者： Hua-Shan Lai Hao Chen Chu-Hao Xia si-yuan Yu Cheng He Yan-feng Chen National Laboratory of Solid State Microstructures&Department of Materials Science and Engineering Nanjing UniversityNanjng 210093China Collaborative Innovation Center of Advanced Microstructures Nanjing University Nanjng 210093China Jiangsu Key Laboratory of Artificial Functional Materials Nanjing University Nanjing 210093China

Classical-wave topological materials lacking intrinsic half-integer spins are less robust while more ***,we explore a single 3-dimensional phononic topological crystalline insulator that simultaneously exhibits a whole family of first-order quadratic surface,second-order hinge,and third-order corner states within the same *** a topological crystalline insulator hosting all-order phases originates from the different topological nature when hierarchically projected onto different facets and lower dimensions,thus free from trivial cladding *** work offers an ideal platform for either robust wave propagation or localization in on-demand dimensions and may facilitate dimension division multiplexing technology.

关键词： topological dimensions crystalline

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Properties of collective flow and pion production in intermediate-energy heavy-ion collisions with a relativistic quantum molecular dynamics model

引用

Nuclear Science and Techniques 2024年第1期35卷 155-169页

作者： si-Na Wei Zhao-Qing feng School of Physics and Optoelectronics South China University of TechnologyGuangzhou 510640China

The relativistic mean-field approach was implemented in the Lanzhou quantum molecular dynamics transport model(***). Using the ***, the properties of collective flow and pion production were investigated systematically for nuclear reactions with various isospin asymmetries. The directed and elliptic flows of the *** are able to describe the experimental data of STAR Collaboration. The directed flow difference between free neutrons and protons was associated with the stiffness of the symmetry energy, that is, a softer symmetry energy led to a larger flow difference. For various collision energies, the ratio between the π^(-) and π^(+) yields increased with a decrease in the slope parameter of the symmetry energy. When the collision energy was 270 MeV/nucleon, the single ratio of the pion transverse momentum spectra also increased with decreasing slope parameter of the symmetry energy in both nearly symmetric and neutron-rich ***, it is difficult to constrain the stiffness of the symmetry energy with the double ratio because of the lack of threshold energy correction on the pion production.

关键词： Heavy-ion collision Collective flow Pion production Symmetry energy Relativistic mean field

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Energy partition in laser-induced cavitation bubbles near the rigid wall with a gas-containing hole

引用

Journal of Hydrodynamics 2024年第3期36卷 435-443页

作者： Dong-qiao He Hai-gang Wen si-yuan Geng Chen-xi Yang Qiang Zhong Zhi-feng Yao College of Water Resources and Civil Engineering China Agricultural UniversityBeijing100083China PowerChina Beijing Engineering Corporation Limited Beijing100024China State Key Laboratory of Efficient Utilization of Agricultural Water Resources Beijing100083China Beijing Engineering Research Center of Safety and Energy Saving Technology for Water Supply Network System China Agricultural UniversityBeijing100083China

To investigate the energy partition in laser-induced cavitation bubbles near the rigid wall with a gas-containing hole,we utilized a nanosecond resolution photography system based on a Q-switched Nd:YAG laser and conventional industrial camera to carefully observe the transient process of bubble collapse near the rigid wall with a gas-containing *** analyzed the generation of collapse microjets and the emission of collapse shock *** found that the cavitation bubble near the rigid wall with a gas-containing hole collapsed at different times and space,and produced various types of shock *** on the far field pressure information of the shock waves measured by hydrophone,the energy of the shock waves generated by the bubble collapse near the rigid wall with a gas-containing hole is calculated for the first *** results show that the ratio of collapse shock wave energy to bubble energy is approximately between 0.7 and 0.8.

关键词： Energy partition bubble collapse laser-induced shock wave gas-containing hole

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

The noise spectral characteristics and noise reduction schemes of screw air-source heat pump:A case study

引用

Building simulation 2024年第1期17卷 53-70页

作者： Dongsheng Liu Yaohan feng Jikang Jia Pengfei si Ya feng China Southwest Architecture Design and Research Institute Co.Ltd. Chengdu 610041China CSCEC Green Construction Engineering Research Center Chengdu 610041China

The screw air-source heat pump can cause incessant high noise levels during operation,which might hinder adoption of this energy-efficient heat ***,acoustic measurements and comparison testing were performed in this *** measurements revealed that the compressor is the main noise source of the heat pump,and it shows a multipeak frequency distribution and a wide frequency spectrum under different work conditions,with multiple peaks at 63,250,and 1000 ***,a compressor sound insulation cover with broadband absorption was proposed,and it was experimentally proven that the insulation cover can reduce the maximum sound pressure level of one unit from 89.8 dBA to 79.1 ***,we proposed several noise reduction strategies and compared their noise reduction effects using computer *** results showed that the noise problem can be effectively improved through the rational design of the sound barrier and the layout and opening options of heat *** distance between the sound barrier and heat pump and the sound attenuation due to diffraction ALa exhibit a U-shaped *** buildings of different heights,the optimal heights of noise barrier are *** 5.5-meter is the optimal height of the sound barrier for single-story *** conclusions can be applied to other building projects for heat pump noise reduction.

关键词： acoustic simulation broadband noise noise reduction air-source heat pump sound barrier

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

A Trust Evaluation Mechanism Based on Autoencoder Clustering Algorithm for Edge Device Access of IoT

引用

Computers, Materials & Continua 2024年第2期78卷 1881-1895页

作者： Xiao feng Zheng yuan Cyber Security Academy Beijing University of Posts and TelecommunicationsBeijing100876China Department of Cyberspace Security Beijing Electronic Science and Technology InstituteBeijing100070China State Grid Info-Telecom Great Power Science and Technology Co. Ltd.Beijing102211China

First,we propose a cross-domain authentication architecture based on trust evaluation mechanism,including registration,certificate issuance,and cross-domain authentication processes.A direct trust evaluation mechanism based on the time decay factor is proposed,taking into account the influence of historical interaction *** weight the time attenuation factor to each historical interaction record for updating and got the new historical record *** refer to the beta distribution to enhance the flexibility and adaptability of the direct trust assessment model to better capture time trends in the historical *** we propose an autoencoder-based trust clustering *** perform feature extraction based on *** leibler(KL)divergence is used to calculate the reconstruction *** constructing a convolutional autoencoder,we introduce convolutional neural networks to improve training efficiency and introduce sparse constraints into the hidden layer of the *** sparse penalty term in the loss function measures the difference through the KL *** clustering is performed based on the density based spatial clustering of applications with noise(DBSCAN)clustering *** the clustering process,edge nodes have a variety of trustworthy attribute *** assign different attribute weights according to the relative importance of each attribute in the clustering process,and a larger weight means that the attribute occupies a greater weight in the calculation of ***,we introduced adaptive weights to calculate comprehensive trust *** experiments prove that our trust evaluation mechanism has excellent reliability and accuracy.

关键词： Cross-domain authentication trust evaluation autoencoder

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Recent Advances in Deciphering the Mechanisms and Biological Functions of DNA Demethylation

引用

Chinese Journal of Chemistry 2024年第6期42卷 645-651页

作者： Yang feng Sheng-Jun Chen Bi-feng yuan Key Laboratory of Aquatic Product Processing Ministry of Agriculture and Rural AffairsNational R&D Center for Aquatic Product ProcessingSouth China Sea Fisheries Research InstituteChinese Academy of Fishery SciencesGuangzhouGuangdong510300 China School of Public Health Research Center of Public HealthRenmin Hospital of Wuhan UniversityWuhan UniversityWuhanHubei430071 China

5-Methylcytosine (5mC) is a dynamic and reversible epigenetic modification in genomic DNA of higher *** has been well-established that the demethylation of 5mC occurs through the ten-eleven translocation (TET)-mediated oxidation of 5mC followed by thymine DNA glycosylase (TDG)-initiated base excision repair (BER).Recent findings also have identified an alternative pathway of DNA *** this pathway,TET enzymes directly oxidize 5mC to form 5-formylcytosine (5fC) or 5-carboxylcytosine (5caC).These modified bases can undergo direct deformylation or decarboxylation,***,DNA demethylation can also occur through the deamination of 5mC and 5hmC,resulting in the production of thymine and 5-hydroxymethyluracil (5hmU),*** DNA demethylation pathways possess critical functional implications and roles in biological *** Recent Advances article will focus on the studies of mechanisms and biological functions of DNA demethylation,shedding light on the reversible nature of the epigenetic modification of 5mC.

关键词： Epigenetics DNA DNA methylation 5-Methylcytosine Demethylation Mechanisms Biological functions C—C bond cleavage Mass spectrometry

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Bridging buried interface enable 24.67%-efficiency doctor-bladed perovskite solar cells in ambient condition

引用

Nano Research 2024年第9期17卷 8068-8076页

作者： Jianhui Chang Erming feng Xiangxiang feng Hengyue Li Yang Ding Caoyu Long siyuan Lu Haixia Zhu Wen Deng Jiayan Shi Yingguo Yang si Xiao Yongbo yuan Junliang Yang Hunan Key Laboratory for Super-microstructure and Ultrafast Process School of PhysicsCentral South UniversityChangsha 410083China Hunan Key Laboratory of Nanophotonics and Devices School of PhysicsCentral South UniversityChangsha 410083China Textile and Fashion Collage Hunan Institute of EngineeringXiangtan 411101China Shanghai Synchrotron Radiation Facility Shanghai Advanced Research InstituteChinese Academy of SciencesShanghai 201204China State Key Laboratory of Powder Metallurgy Central South UniversityChangsha 410083China

Scalable deposition of high-efficiency perovskite solar cells(PSCs)is critical to accelerating their commercial ***,a significant number of defects are distributed at the buried interface of perovskite film fabricated by scalable deposition,exhibiting much negative influence on the efficiency and stability of ***,2-(N-morpholino)ethanesulfonic acid potassium salt(MESK)is incorporated as the bridging layer between the tin oxide(SnO_(2))electron transport layer(ETL)and the perovskite film deposited via scalable two-step doctor *** experiment and simulation results demonstrate that MESK can passivate the trap states of Sn suspension bonds,thereby enhancing the charge extraction and transport of the SnO_(2)***,the strong interaction with uncoordinated Pb ions can modulate the crystal growth and crystallographic orientation of perovskite film and passivate buried *** employing MESK interface bridging,PSCs fabricated via scalable doctor blading in ambient condition achieve a power conversion efficiency(PCE)of 24.67%,which is one of the highest PCEs for doctor-bladed PSCs,and PSC modules with an active area of 11.35 cm^(2)achieve a PCE of 19.45%.Furthermore,PSCs exhibit excellent long-term stability,and the unpackaged target device with a storage of 1680 h in ambient condition(25℃and humidity of 30%relative humidity(RH))can maintain more than 90%of the initial *** research provides a strategy for constructing a high-performance interface bridge between SnO_(2)ETL and perovskite film,and achieving efficient and stable large-area PSCs and modules fabricated via scalable doctor-blading process in ambient condition.

关键词： perovskite solar cells doctor blading buried interface defect passivation orientation regulation

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Demethylase-assisted site-specific detection of N^(1)-methyladenosine in RNA

引用

Chinese Chemical Letters 2024年第5期35卷 397-401页

作者： Jun Xiong Ke-Ke Chen Neng-Bin Xie Wei Chen Wen-Xuan Shao Tong-Tong Ji si-Yu Yu Yu-Qi feng Bi-feng yuan College of Chemistry and Molecular Sciences Research Center of Public HealthRenmin Hospital of Wuhan UniversitySchool of Public HealthWuhan UniversityWuhan 430071China Department of Laboratory Medicine Zhongnan Hospital of Wuhan UniversityWuhan UniversityWuhan 430071China

The dynamic RNA modifications have been viewed as new posttranscriptional regulator in modulating gene expression as well as in a broad range of physiological processes.N^(1)-methyladenosine(m^(1)A)is one of the most prevalent modifications existing in multiple types of ***-depth investigation of the functions of m^(1)A requires the site-specific assessment of m^(1)A stoichiometry in ***,we established a demethylase-assisted method(DA-m^(1)A)for the site-specific detection and quantification of m^(1)A in RNA.N^(1)-methyl group in m^(1)A could result in the stalling of reverse transcription at m^(1)A site,thus producing the truncated *** AlkB is a demethylase that can demethylate m^(1)A to produce adenine in RNA,thus generating full-length cDNA from AlkB-treated *** of the produced amounts of full-length cDNA by quantitative real-time PCR can achieve the site-specific detection and quantification of m^(1)A in *** the DA-m^(1)A method,we examined and successfully confirmed the previously well-characterized m^(1)A sites in various types of RNAs with low false positive *** addition,we found that the level of m^(1)A was significantly decreased at the bromodomain containing 2(BRD2)mRNA position 1674 and CST telomere replication complex component 1(CTC1)mRNA position 5643 in human hepatocellular carcinoma *** results suggest that these two m^(1)A sites in mRNA may be involved in liver *** together,the DA-m^(1)A method is simple and enables the rapid,cost-effective,and site-specific detection and quantification of m^(1)A in RNA,which provides a valuable tool to decipher the functions of m^(1)A in human diseases.

关键词： N^(1)-methyladenosine RNA modification AlkB demethylase RNA epigenetics Quantitative real-time PCR Hepatocellular carcinoma

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

欢迎您,

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案：

请选择收藏分类：

通借通还

欢迎您,

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：