检索结果-南通市图书馆

Visualization of mF/Diesel RCCI Combustion Process and Soot Emission

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Journal of Thermal Science 2024年第2期33卷 779-792页

作者： HUANG Chen ni Xiao GE Dameng lI Song ZHANG Wanzhi lIU Jinping ZHANG Tingting School of mechanical and Electronic Engineering Shandong Agricultural UniversityTaian271018China Shandong Provincial Engineering laboratory of Agricultural Equipment Intelligence Taian271018China Taian Technician Institute Taian271000China Sinotruk Taian Wuyue Special Vehicle Co. Ltd.Taian271000China School of mechanical Engineering Shaanxi University of TechnologyHanzhong723001China School of mechanical Engineering Anyang Institute of TechnologyAnyang455000China

based on the optical engine,the ignition characteristics,combustion process and soot emission characteristics of diesel under different 2-methylfuran(mF) atmospheres were investigated by high-speed photography and in-cylinder combustion analysis *** results show that at the same main injection timing,the ignition time of reactivity controlled compression ignition(RCCI) combustion mode is earlier than pure diesel combustion,and the ignition point is concentrated near the *** acts as a spark plug to ignite the mixture,but the flame develops slowly in the early stages and the pressure in the cylinder rises *** with pure diesel,RCCI combustion model has smaller peak values of in-cylinder pressure and heat release rate,shorter ignition delay period,earlier combustion phase and shorter combustion *** main spray time at 6℃A bTDC and 12℃A bTDC,with the increase of mF premixing ratio from 0 to 0.75,the peak cylinder pressure decreased by 19.6% and 26% *** addition,with the increase of the mF heat value ratio,the area of Kl factor> 1.5 in the combustion chamber decreased and the space integral natural luminescence(SINl) peak value decreased by 48.37%,and the soot formation rate and yield decreased ***,when the mF heat value ratio was too large(75% of the total calorific value),the ignition delay period increased,and misfire occurred at the main injection timing of 0℃A *** RCCI mode of mF/diesel dual fuel has better stability,and better control effect can be obtained at different main inj ection timing.

关键词： 2-methylfuran RCCI visualization two-color method Kl factor

Three-year field study on grass growth and soil hydrological properties in biochar-amended soil

在线全文

学校读者我要写书评

暂无评论

Journal of Rock mechanics and Geotechnical Engineering 2024年第7期16卷 2764-2774页

作者： Haowen Guo Charles Wang Wai Ng Junjun ni Qi Zhang Yuchen Wang Department of Civil and Environmental Engineering The Hong Kong University of Science and TechnologyHong KongChina School of Transportation Southeast UniversityNanjingChina

Field monitoring was conducted to investigate and quantify the long-term effects of peanut shell biochar on soil-grass interaction over three *** 10 m5 m grassed plots were constructed in completely decomposed granitic *** of them were amended,respectively,with 5%and 10%biochar contents(m^(3)/m^(3))for grass growth,while the third was without biochar *** the threeyear monitoring,plant characteristics,saturated water permeability(k_(s))of grassed soil and soil suction were *** monitored results show that the grass leaf area index(lAI)and root length density(RlD)with biochar amendment were improved by 38%and 200%,*** the grassed plot without biochar,a threshold RlD existed with a value of 1.7 cm/cm^(3),beyond which k_(s) raised *** threshold RlD increased by 52%when biochar content increased from 0%to 10%.This implies that biochar may restrict the increase in k_(s) of grassed soil due to the rise in the threshold *** presence of biochar and grass can retain over 100%higher suction after heavy rainfalls,while 54%lower peak suction under evapotranspiration(ET)compared with the non-amended *** can alleviate the negative effects on hydraulic properties caused by plant growth and reduce ET-induced excessive water loss.A 5%peanut shell biochar content is recommended for the long-term management of vegetated earthen infrastructures.

关键词： Soil-grass interaction biochar long-term Water infiltration Soil drying

A highly sensitive ratiometric near-infrared nanosensor based on erbium-hyperdoped silicon quantum dots for iron(Ⅲ) detection

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Semiconductors 2024年第8期45卷 49-58页

作者： Kun Wang Wenxuan lai Zhenyi ni Deren Yang Xiaodong Pi State Key laboratory of Silicon and Advanced Semiconductor materials&School of materials Science and Engineering Zhejiang UniversityHangzhou 310027China Institute of Advanced Semiconductors&Zhejiang Provincial Key laboratory of Power Semiconductor materials and Devices ZJ-UHangzhou Global Scientific and Technological Innovation CenterZhejiang UniversityHangzhou 311215China

Ratiometric fluorescent detection of iron(Ⅲ)(Fe^(3+))offers inherent self-calibration and contactless analytic ***,realizing a dual-emission near-infrared(niR)nanosensor with a low limit of detection(lOD)is rather *** this work,we report the synthesis of water-dispersible erbium-hyperdoped silicon quantum dots(Si QDs:Er),which emit niR light at the wavelengths of 810 and 1540 nm.A dual-emission niR nanosensor based on water-dispersible Si QDs:Er enables ratiometric Fe^(3+)detection with a very low lOD(0.06μm).The effects of pH,recyclability,and the interplay between static and dynamic quenching mechanisms for Fe^(3+)detection have been systematically *** addition,we demonstrate that the nanosensor may be used to construct a sequential logic circuit with memory functions.

关键词： erbium-hyperdoped silicon quantum dots dual-emission near-infrared nanosensor Fe^(3+)detection sequential logic circuit

A statistical analysis of the Kappa-type energy spectrum distribution of radiation belt electrons observed by Van Allen Probes

在线全文

学校读者我要写书评

暂无评论

Earth and Planetary Physics 2024年第2期8卷 368-374页

作者： luHuai Jiao Xin ma YuanNong Zhang TaiFeng Jin Song Fu binbin ni Department of Space Physics School of Electronic InformationWuhan UniversityWuhan 430072China

The energy spectrum of energetic electrons is a key factor representing the dynamic variations of Earth’s Van Allen radiation *** measurements have indicated that the commonly used maxwellian and Kappa distributions are inadequate for capturing the realistic spectral distributions of radiation belt *** we adopt the Kappa-type(KT)distribution as the fitting function and perform a statistical analysis to investigate the radiation belt electron flux spectra observed by the Van Allen *** calculating the optimal values of the key KT distribution parameters(i.e.,κandθ2)from the observed spectral shapes,we fit the radiation belt electron fluxes at different l-shells under different geomagnetic *** this manner,we obtain typical values of the KT distribution parameters,which are statistically feasible for modeling the radiation belt electron flux profiles during either geomagnetically quiet or active periods.A comparison of the KT distribution model results with those using the maxwellian or Kappa distribution reveals the advantage of the KT distribution for studying the overall properties of the radiation belt electron spectral distribution,which has important implications for deepening the current understanding of the radiation belt electron dynamics under evolving geomagnetic conditions.

关键词： radiation belt electron Kappa-type distribution fitting geomagnetic storm

Quantum correlations and entanglement in coupled optomechanical resonators with photon hopping via Gaussian interferometric power analysis

在线全文

学校读者我要写书评

暂无评论

Chinese Physics b 2024年第5期33卷 204-211页

作者： Y.lahlou b.maroufi m.Daoud lPHE-mS Department of PhysicsFaculty of SciencesMohammed V UniversityRabatMorocco lPmS Department of PhysicsFaculty of SciencesIbn Tofail UniversityKénitraMorocco

Quantum correlations that surpass entanglement are of great importance in the realms of quantum information processing and quantum ***,for quantum systems prepared in pure states,it is difficult to differentiate between quantum entanglement and quantum ***,this indistinguishability is no longer holds for mixed *** contribute to a better understanding of this differentiation,we have explored a simple model for both generating and measuring these quantum *** study concerns two macroscopic mechanical resonators placed in separate Fabry–Pérot cavities,coupled through the photon hopping *** system offers a comprehensively way to investigate and quantify quantum correlations beyond entanglement between these mechanical *** key ingredient in analyzing quantum correlation in this system is the global covariance *** forms the basis for computing two essential metrics:the logarithmic negativity(E_(N)^(m))and the Gaussian interferometric power(P_(G)^(m)).These metrics provide the tools to measure the degree of quantum entanglement and quantum correlations,*** study reveals that the Gaussian interferometric power(P_(G)^(m))proves to be a more suitable metric for characterizing quantum correlations among the mechanical modes in an optomechanical quantum system,particularly in scenarios featuring resilient photon hopping.

关键词： quantum correlations entanglement Gaussian interferometric power logarithmic negativity optomechanics photon hopping

Carbon monoxide as C1 building block in Fine Chemical Synthesis

在线全文

学校读者我要写书评

暂无评论

Chinese Journal of Chemistry 2024年第2期42卷 199-221页

作者： Rui m.b.Carrilho mario J.F.Calvete Gabor mikle laszlo Kollar mariette m.Pereira University of Coimbra Coimbra Chemistry CentreDepartment of ChemistryRua Larga3004-535 CoimbraPortugal Department of General and Inorganic Chemistry and ElKH-PTE Research Groupfor Selective Chemical Syntheses University of PecsIfjusag utja 6H-7624 PecsHungary

Carbon monoxide(CO)has become one of the most relevant and versatile renewable C1 building blocks for chemical synthesis,especially in the fine chemicals industry,due to the development of efficient and selective catalysts for its *** this review,we present a comprehensive critical analysis of the last 10 years literature on the use of CO as a renewable feedstock for fine chemicals *** review is organized by type of catalytic reaction,namely alkene and alkyne carbonylation,hydroformylation,carbonylation of aryl halides,carbonylative cross-coupling and C-H *** examples of the synthesis of relevant building blocks and/or known pharmaceuticals are *** is placed on examples of utilizing CO as the C1 building block in one or more catalytic *** catalyst used and the reaction conditions are consistently presented throughout all of the examples.

关键词： Carbon monoxide Fine chemicals Carbonylation Hydroformylation C-H functionalization

Rational Design of Ruddlesden-Popper Perovskite Ferrites as Air Electrode for Highly Active and Durable Reversible Protonic Ceramic Cells

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Nano-micro letters 2024年第9期16卷 308-324页

作者： Na Yu Idris Temitope bello Xi Chen Tong liu Zheng li Yufei Song meng ni Department of building and Real Estate Research Institute for Sustainable Urban Development(RISUD)and Research Institute for Smart Energy(RISE)The Hong Kong Polytechnic UniversityHung HomKowloonHong KongPeople’s Republic of China The Hong Kong Polytechnic University Shenzhen Research Institute Shenzhen 518057GuangdongPeople’s Republic of China Department of mechanical and Aerospace Engineering The Hong Kong University of Science and TechnologyClear Water BayHong KongPeople’s Republic of China

Reversible protonic ceramic cells(RePCCs)hold promise for efficient energy storage,but their practicality is hindered by a lack of high-performance air electrode ***-Popper perovskite Sr_(3)Fe_(2)O_(7−δ)(SF)exhibits superior proton uptake and rapid ionic conduction,boosting ***,excessive proton uptake during RePCC operation degrades SF’s crystal structure,impacting *** study introduces a novel A/b-sites co-substitution strategy for modifying air electrodes,incorporating Sr-deficiency and Nb-substitution to create Sr_(2.8)Fe_(1.8)Nb_(0.2)O_(7−δ)(D-SFN).Nb stabilizes SF’s crystal,curbing excessive phase formation,and Sr-deficiency boosts oxygen vacancy concentration,optimizing oxygen *** D-SFN electrode demonstrates outstanding activity and durability,achieving a peak power density of 596 mW cm^(−2)in fuel cell mode and a current density of−1.19 A cm^(−2)in electrolysis mode at 1.3 V,650℃,with excellent cycling *** approach holds the potential for advancing robust and efficient air electrodes in RePCCs for renewable energy storage.

关键词： Reversible protonic ceramic cells Air electrode Ruddlesden-Popper perovskite Hydration Oxygen reduction reaction

Reasons and promotion strategies of physical activity constraints in obese/ overweight children and adolescents

在线全文

学校读者我要写书评

暂无评论

Sports medicine and Health Science 2024年第1期6卷 25-36页

作者： Jiangxi Chen Yinmengke bai Weiguang ni Physical Education College Jilin University130012ChangchunChina

To explore the reasons for low levels of physical activity in obese/overweight children and adolescents and to propose appropriate strategies to promote their physical activity(PA).This review followed the Preferred Reporting Items for Systematic Reviews and meta-Analyses(PRISmA)guidelines by searching and analyzing the literature of studies related to physical activity in obese/overweight children and adolescents published between January 2003 and January 2023 in Web of Science,Scopus,and Pubmed databases.A total of 31 relevant studies were included for analysis,of which 16 were quantitative and 15 *** to these studies,the PA of obese/overweight children and adolescents is mainly constrained by negative factors:Individual,interpersonal,and *** these factors,low levels of individual motivation and psychological sensitivity and vulnerability,lack of family support,negative social feedback,insufficient protection from government policies,and inadequate support from the built environment are the main reasons that constrain their *** promotion of PA in obese/overweight children and adolescents,who are subject to more constraints at all levels,requires a system of security that involves the government,the community,the school,and the family to address the problems they encounter and enhance the sustainability of engagement in PA.

关键词： Obesity Overweight Children Adolescents Physical activity

multi-layer hierarchical cellulose nanofibers/carbon nanotubes/vinasse activated carbon composite materials for supercapacitors and electromagnetic interference shielding

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Nano Research 2024年第3期17卷 904-912页

作者： Tianxu Wang Chuanyin Xiong Yongkang Zhang bo Wang Qing Xiong mengjie Zhao Yonghao ni College of bioresources Chemical&materials Engineering Shaanxi University of Science and TechnologyXi’an 710021China Department of Chemical and biomedical Engineering The University of MaineOronoME 04469USA University of New brunswick Limerick Pulp&Paper CtrFrederictonNB E3B 5A3Canada

Developing porous self-supporting electrodes with excellent conductivity,good mechanical properties,and high electrochemical activity is crucial for constructing electrode materials with lightweight,ultra-thin,flexible,and high capacitance *** this work,we prepared a cellulose nanofibers(CNFs)/carbon nanotubes(CNTs)/vinasse activated carbon(VAC)(CCV)composite material with a multi-layer hierarchical conductive structure through simple vacuum filtration and *** this composite material,the self-assembly of CNF provides the main skeleton structure of a multi-layer hierarchical *** provides a fast path for the rapid transfer of electrons and is beneficial for the loss of electromagnetic *** provides sufficient double layer *** synergistic effect of the above three endows CCV composite materials with excellent energy storage performance and electromagnetic interference(EmI)shielding *** addition,we endowed the CCV composite with a certain shape and performance by introducing a vitrimer polymer with a dynamic cross-linked network *** summary,thanks to the synergistic effect of various components in the multi-layer hierarchical structure,CCV composite materials exhibit excellent integration performance,especially stable energy storage performance and EmI shielding *** significant properties make CCV composite materials have great application prospects in the fields of energy storage and intelligent EmI shielding.

关键词： self-supporting electrodes multi-layer hierarchical structure supercapacitors electromagnetic interference shielding