检索结果-南通市图书馆

Chinese Journal of Chemical Engineering 2024年第1期65卷 1-7页

作者： Risheng Shen Shilong Li Yuqing Sun Yuan bai Jian Lu Wenheng Jing State Key Laboratory of Materials-Oriented Chemical Engineering Nanjing Tech UniversityNanjing 210009China National Energy Group Science and Technology Research Institute Co. Ltd.Nanjing 210023China

Membrane technology has become the mainstream process for the production of electronic grade hydrogen peroxide(H_(2)O_(2)).But due to the oxidation degradation of the organic membranes(***)by the strong oxidative radicals(e.g.OH)generated via the activation of H_(2)O_(2)by iron ions(Fe^(3+)),the short effective lifetime of membranes remains a *** nano tin oxide(SnO_(2))has great potential for the removal of Fe^(3+)in strongly oxidative H_(2)O_(2)because of its ability to stabilize H2O_(2)and preferentially adsorb Fe^(3+).Herein,we have designed for the first time a flower-like robust SnO_(2)membrane on the ceramic support by in situ template-free one-step hydrothermal *** three-dimensional loose pore structure in the membrane built by interlacing SnO_(2)nanosheets endows the SnO_(2)membrane with a high specific surface area and abundant adsorption sites(AOH).Based on the coordination complexation and electrostatic attraction between the SnO_(2)surface and Fe^(3+),the membrane shows a high Fe3+removal efficiency(83%)and permeability(24 L·m^(-2)·h^(-1)·MPa^(-1))in H_(2)O_(2).This study provides an innovative and simple approach to designing robust SnO_(2)membranes for highly efficient removal of Fe^(3+)in harsh environments,such as strong oxidation conditions.

关键词： Hydrogen peroxide SnO_(2)membrane Adsorption Hydrothermal

Hydrodynamic analysis of carbon nanotube clusters in distributor-less conical fluidized beds with step-by-step scaling

在线全文

学校读者我要写书评

暂无评论

Chinese Journal of Chemical Engineering 2024年第3期67卷 117-125页

作者： Tianle Zhang Wenjuan bai Qianpeng Dong Dianming Chu Lianlian Wang Yan He Shandong Engineering Laboratory for Preparation and Application of High-performance Carbon-Materials College of Electromechanical EngineeringQingdao University of Science and TechnologyQingdao 266061China Shandong Dazhan Nano Materials Co. Ltd.Binzhou 256220China

As a high-performance material with great application potential,the application of carbon nanotubes has been limited by their production volume.A distributor-less conical fluidized bed is the main equipment used in the industrial production of carbon *** improve the production volume and product quality of carbon nanotubes,the study of fluidized-bed-diameter scaling is *** different diameters of distributor-less conical fluidized beds were established,and then the particle behavior and bubble characteristics of carbon nanotube clusters at these bed diameters were ***-series and wavelet analysis methods were used to analyze the pressure-fluctuation signals inside the fluidized *** showed that the distributor-less design caused the airflow to break through the middle of the bed,which did not change with the change in bed *** powder-bridging phenomenon of carbon nanotube clusters in a 100-mm-diameter fluidized bed was related to the special microstructure of carbon nanotube *** frequency of pressure fluctuations in the bed decreased nonlinearly with increasing bed *** study can guide the design and scale-up of distributor-less conical fluidized beds,especially for the scale-up of carbon nanotube production equipment,which can contribute to the improvement of carbon nanotubes’capacity and quality in industrial production.

关键词： Carbon nanotubes Fluidized bed Multiphase flow Scale-up Multiscale

Two diversities meet in the rhizosphere:root specialized metabolites and microbiome

在线全文

学校读者我要写书评

暂无评论

Journal of Genetics and Genomics 2024年第5期51卷 467-478页

作者： Xiaochen Wang Jingying Zhang Xinjun Lu Yang bai Guodong Wang State Key Laboratory of Plant Genomics Institute of Genetics and Developmental BiologyThe Innovative Academy of Seed DesignChinese Academy of SciencesBeijing 100101China CAS-JIC Centre of Excellence for Plant and Microbial Science Institute of Genetics and Developmental BiologyChinese Academy of SciencesBeijing 100101China Hainan Yazhou Bay Seed Laboratory SanyaHainan 572025China College of Advanced Agricultural Sciences Chinese Academy of SciencesBeijing 100049China

Plants serve as rich repositories of diverse chemical compounds collectively referred to as specialized *** compounds are of importance for adaptive processes,including interactions with various microbes both beneficial and *** microbes as bioreactors,the chemical diversity undergoes dynamic changes when root-derived specialized metabolites(RSMs)and microbes encounter each other in the *** advancements in sequencing techniques and molecular biology tools have not only accelerated the elucidation of biosynthetic pathways of RSMs but also unveiled the significance of RSMs in plant-microbe *** this review,we provide a comprehensive description of the effects of RSMs on microbe assembly in the rhizosphere and the influence of corresponding microbial changes on plant health,incorporating the most up-to-date information ***,we highlight open questions that remain for a deeper understanding of and harnessing the potential of RSM-microbe interactions to enhance plant adaptation to the ***,we propose a pipeline for investigating the intricate associations between root exometabolites and the rhizomicrobiome.

关键词： Root specialized metabolites Microbiome Plant-microbe interactions Rhizosphere Diversity

A low-noise,high-gain,and large-dynamic-range photodetector based on a JFET and a charge amplifier

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Frontiers of Information Technology & Electronic Engineering 2024年第2期25卷 316-322页

作者： Jinrong WANG Shuang'e WU Chengdong MI Yaner QIU Xin'ai bai Department of Physics Lyuliang UniversityLvliang033001China Guangdong Provincial Key Laboratory of Fiber Laser Materials and Applied Techniques South China University of TechnologyGuangzhou510640China

We demonstrate a low-noise,high-gain,and large-dynamic-range photodetector(PD)based on a junction field-effect transistor(JFET)and a charge amplifier for the measurement of quantum noise in Bell-state detection(BSD).Particular photodiode junction capacitance allows the silicon N-channel JFET 2sk152 to be matched to the noise requirement for charge amplifier *** electronic noise of the PD is effectively suppressed and the signal-to-noise ratio(SNR)is up to 15 dB at the analysis frequency of 2.75 MHz for a coherent laser power of 50.08µ*** combining of the inductor and capacitance,the alternating current(AC)and direct current(DC)branches of the PD can operate linearly in a dynamic range from 25.06µW to 17.50 *** PD can completely meet the requirements of SNR and dynamic range for BSD in quantum optics experiments.

关键词： Quantum noise Bell-state detection(BSD) Photodetector(PD) Junction field-effect transistor(JFET) Charge amplifier

Investigations of the mechanical response of dummy HTPB propellant grain under ultrahigh acceleration overload conditions using onboard flight-test measurements

在线全文

学校读者我要写书评

暂无评论

Defence Technology（防务技术） 2024年第2期32卷 473-484页

作者： Yiming Zhang Ningfei Wang Weihua Ma Ran Wang Long bai Yi Wu School of Aerospace Engineering Beijing Institute of TechnologyBeijing 100081China Beijing System Design Institute of Electro-mechanic Engineering Beijing 100854China Xi'an Changfeng Research Institute of Mechanism and Electricity Xi'an 710065China

In this paper,to study the mechanical responses of a solid propellant subjected to ultrahigh acceleration overload during the gun-launch process,specifically designed projectile flight tests with an onboard measurement system were *** projectiles containing dummy HTPB propellant grains were successfully recovered after the flight tests with an ultrahigh acceleration overload value of 8100 *** onboard-measured time-resolved axial displacement,contact stress and overload values were successfully obtained and *** compression tests of the dummy HTPB propellant used in the gunlaunched tests were carried out at low and intermediate strain rates to characterize the propellant's dynamic properties.A linear viscoelastic constitutive model was employed and applied in finite-element simulations of the projectile-launching *** the launch process,the dummy propellant grain exhibited large deformation due to the high acceleration overload,possibly leading to friction between the motor case and propellant *** calculated contact stress showed good agreement with the experimental results,though discrepancies in the overall displacement of the dummy propellant grain were *** dynamic mechanical response process of the dummy propellant grain was analysed in *** results can be used to estimate the structural integrity of the analysed dummy propellant grain during the gun-launch process.

关键词： Gun-launched flight test Dummy HTPB propellant Onboard measurements Utrahigh overload Mechanical response

Optimized Mask-RCNN model for particle chain segmentation based on improved online ferrograph sensor

在线全文

学校读者我要写书评

暂无评论

Friction 2024年第6期12卷 1194-1213页

作者： Shuo WANG Miao WAN Tonghai WU Zichen bai Kunpeng WANG Key Laboratory of Education Ministry for Modern Design and Rotor-Bearing System Xi’an Jiaotong UniversityXi’an 710049China

Ferrograph-based wear debris analysis(WDA)provides significant information for wear fault analysis of mechanical *** decades of offline application,this conventional technology is being driven by the online ferrograph sensor for real-time wear state ***,online ferrography has been greatly limited by the low imaging quality and segmentation accuracy of particle chains when analyzing degraded lubricant oils in practical *** address this issue,an integrated optimization method is developed that focuses on two aspects:the structural re-design of the online ferrograph sensor and the intelligent segmentation of particle *** enhancing the imaging quality of wear particles,the magnetic pole of the online ferrograph sensor is optimized to enable the imaging system directly observe wear particles without penetrating ***,a light source simulation model is established based on the light intensity distribution theory,and the LED installation parameters are determined for particle illumination uniformity in the online ferrograph *** this basis,a Mask-RCNN-based segmentation model of particle chains is constructed by specifically establishing the region of interest(ROI)generation layer and the ROI align layer for the irregular particle *** these measures,a new online ferrograph sensor is designed to enhance the image acquisition and information extraction of wear *** verification,the developed sensor is tested to collect particle images from different degraded oils,and the images are further handled with the Mask-RCNN-based model for particle feature *** results reveal that the optimized online ferrography can capture clear particle images even in highly-degraded lubricant oils,and the illumination uniformity reaches 90%in its imaging *** importantly,the statistical accuracy of wear particles has been improved from 67.2%to 94.1%.

关键词： wear particle analysis online ferrography particle image acquisition particle chain segmentation

Crack identification in concrete, using digital image correlation and neural network

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Frontiers of Structural and Civil Engineering 2024年第4期18卷 536-550页

作者： Jingyi WANG Dong LEI Kaiyang ZHOU Jintao HE Feipeng ZHU Pengxiang bai College of Mechanics and Materials Hohai UniversityNanjing 211100China

In engineering applications,concrete crack monitoring is very *** methods are of low efficiency,low accuracy,have poor timeliness,and are applicable in only a limited number of ***,more comprehensive detection of concrete damage under different scenarios is of high value for practical engineering *** image correlation(DIC)technology can provide a large amount of experimental data,and neural network(NN)can process very rich ***,NN,including convolutional neural networks(CNN)and back propagation neural networks(BP),can be combined with DIC technology to analyze experimental data of three-point bending of plain concrete and four-point bending of reinforced *** addition,strain parameters can be used for training,and displacement parameters can be added for comprehensive *** data obtained by DIC technology are grouped for training,and the recognition results of NN show that the combination of strain and displacement parameters,i.e.,the response of specimen surface and whole body,can make results more objective and *** identification results obtained by CNN and BP show that these technologies can accurately identify *** identification results for reinforced concrete specimens are less affected by noise than those of plain concrete *** is more convenient because it can identify some features directly from images,recognizing the cracks formed by macro *** can issue early warning of the microscopic cracks,but it requires a large amount of data and *** can be seen that CNN is more intuitive and efficient in image processing,and is suitable when low accuracy is adequate,while BP is suitable for occasions with greater accuracy *** two tools have advantages in different situations,and together they can play an important role in engineering monitoring.

关键词： digital image correlation convolutional neural network back propagation neural neural network damage detection concrete

The Capital Market Reaction and the Influencing Mechanism of the Establishment of the Data Basic Institutional System

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Social Sciences in China 2024年第1期45卷 134-156页

作者： Liu bai Zhang Ailian School of Business and Management Jilin University

This study uses a sample of A-share listed companies to investigate the impact of China's Data Basic Institutional System on capital market reactions and the mechanism by which it exerts *** findings reveal that within a 5-day period before and after the policy announcement,listed companies with high data resources experience a significantly higher abnormal return compared to those with low data ***,this difference becomes more pronounced as enterprise technology intensity ***,the policy enhances the capital market's perception of the value of data resources and its potential for generating multiplier *** tests confirm that post-implementation of the policy,the capital market reevaluates the long-term value of enterprises associated with data *** comprehensive examination contributes empirical evidence to support academic research,inform policy formulation,and guide strategic planning in relevantindustries.

关键词： data resources technology intensity market value event study abnormal return

Effect of surfactant frequently used in soil flushing on oxygen mass transfer in micro-nano-bubble aeration system

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Chinese Journal of Chemical Engineering 2024年第3期67卷 174-181页

作者： Mei bai Zhibin Liu Zhu Liu Chenfei He Zhanhuang Fan Miaoxin Yuan Jiangsu Key Laboratory of Urban Underground Engineering and Environmental Safety Southeast UniversityNanjing 211189China CECEP DADI(Hangzhou)Environmental Remediation Co. Ltd.Hangzhou 310020China

In-site soil flushing and aeration are the typical synergetic remediation technology for contaminated *** surfactant present in flushing solutions is bound to affect the aeration *** purpose of this study is to evaluate the effect of surfactant frequently used in soil flushing on the oxygen mass transfer in micro-nano-bubble(MNB)aeration ***,bio-surfactants and chemical surfactants were used to investigate their effects on Sauter mean diameter of bubble(dBS),gas holdup(ε),volumetric mass-transfer coefficient(kLa)and liquid-side mass-transfer coefficient(kL)in the MNB aeration ***,based upon the experimental results,the Sardeing's and Frossling's models were modified to describe the effect of surfactant on kL in the MNB *** results showed that,for the twenty aqueous surfactant solutions,with the increase in surfactant concentration,the value of dBS,kLa and kL decreased,while the value ofεand gas-liquid interfacial area(a)*** phenomena were mainly attributed to the synergistic effects of immobile bubble surface and the suppression of coalescence in the surfactant *** addition,with the presence of electric charge,MNBs in anionic surfactant solutions were smaller and higher in number than in non-ionic surfactant ***,the accumulation of surfactant on the gas-liquid interface was more conspicuous for small MNB,so the reduction of kL in anionic surfactant solutions was larger than that in non-ionic surfactant ***,the modified Frossling's model predicted the effect of surfactant on kL in MNB aeration system with reasonable accuracy.

关键词： Soil flushing Micro-nano-bubble aeration Bio-surfactant Mass transfer coefficient

The Current Progress and Challenges of Carbonized Polymer Dot-Based Room-Temperature Phosphorescent Materials

在线全文

学校读者我要写书评

暂无评论

CCS Chemistry 2024年第3期6卷 604-622页

作者： Chengyu Zheng Songyuan Tao bai Yang State Key Lab of Supramolecular Structure and Materials College of ChemistryJilin UniversityChangchun 130012

Carbonized polymer dots(CPDs)as one type of carbon dots have attracted widespread attention in recent *** proposal of the“shell–core”structure of CPDs leads to further thinking about the association between their special structures and luminescent *** recent years,great progress has been made in the field of CPD-based room-temperature phosphorescent *** review pays particular attention to how the special“core–shell”structure of CPDs influences the activation of roomtemperature phosphorescence(RTP).The strategies and vital factors to activate RTP for CPD-based materials in both solid state and water were reviewed in detail to elaborate on the effect of the special structure on RTP ***,some perspectives on the current challenges were also provided to guide the further development of CPD-based room-temperature phosphorescent materials.

关键词： room-temperature phosphorescent materials carbon dots carbonized polymer dots “core-shell”structure photoluminescent mechanism