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Magnetic confinement fusion: a brief review

Chuanjun HUANG, Laifeng LI

《能源前沿（英文）》 2018年 第12卷 第2期   页码 305-313 doi: 10.1007/s11708-018-0539-1

摘要： Fusion energy is considered to be the ultimate energy source, which does not contribute to climate change compared with conventional fossil fuel. It is massive compared with unconventional renewable energy and demonstrates fewer safety features compared with unconventional fission energy. During the past several decades, never-ceasing efforts have been made to peacefully utilize the fusion energy in various approaches, especially inertial confinement and magnetic confinement. In this paper, the main developments of magnetic confinement fusion with emphasis on confinement systems as well as challenges of materials related to superconducting magnet and plasma-facing components are reviewed. The scientific feasibility of magnetic confinement fusion has been demonstrated in JET, TFTR, JT-60, and EAST, which instigates the construction of the International Thermonuclear Experimental Reactor (ITER). A fusion roadmap to DEMO and commercial fusion power plant has been established and steady progresses have been made to achieve the ultimate energy source.

关键词： fusion energy     magnetic confinement     tokamak     structural material     superconducting magnet    

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Confinement properties of circular concrete columns wrapped with prefabricated textile-reinforced fine

《结构与土木工程前沿（英文）》 doi: 10.1007/s11709-023-0955-0

摘要： This paper proposes an innovative column composed of a core column (including both reinforced concrete (RC) and plain concrete (PC) columns) and a prefabricated textile-reinforced fine concrete (TRC) shell. To study the confinement properties of TRC shells on this novel type of concrete column, 20 circular specimens, including 12 PC columns and 8 RC columns, were prepared for axial compressive tests. Four key parameters, including the column size, reinforcing ratio of the carbon textile, concrete strength, and stirrup spacing, were evaluated. The results indicated that the compressive properties of the columns were improved by increasing the reinforcing ratio of the textile layers. In the case of TRC-confined PC columns, the maximum improvement in the peak load was 56.3%, and for TRC-confined RC columns, the maximum improvement was 60.2%. Based on the test results, an analytical model that can be used to calculate the stress–strain curves of prefabricated TRC shell-confined concrete columns has been proposed. The calculated curves predicted by the proposed model agreed well with the test results.

关键词： textile-reinforced fine concrete     prefabricated shell     confined concrete column     confinement properties     stress–strain relationship    

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Development of deep neural network model to predict the compressive strength of FRCM confined columns

Khuong LE-NGUYEN; Quyen Cao MINH; Afaq AHMAD; Lanh Si HO

《结构与土木工程前沿（英文）》 2022年 第16卷 第10期   页码 1213-1232 doi: 10.1007/s11709-022-0880-7

摘要： The present study describes a reliability analysis of the strength model for predicting concrete columns confinement influence with Fabric-Reinforced Cementitious Matrix (FRCM). through both physical models and Deep Neural Network model (artificial neural network (ANN) with double and triple hidden layers). The database of 330 samples collected for the training model contains many important parameters, i.e., section type (circle or square), corner radius rc, unconfined concrete strength fco, thickness nt, the elastic modulus of fiber Ef , the elastic modulus of mortar Em. The results revealed that the proposed ANN models well predicted the compressive strength of FRCM with high prediction accuracy. The ANN model with double hidden layers (APDL-1) was shown to be the best to predict the compressive strength of FRCM confined columns compared with the ACI design code and five physical models. Furthermore, the results also reveal that the unconfined compressive strength of concrete, type of fiber mesh for FRCM, type of section, and the corner radius ratio, are the most significant input variables in the efficiency of FRCM confinement prediction. The performance of the proposed ANN models (including double and triple hidden layers) had high precision with R higher than 0.93 and RMSE smaller than 0.13, as compared with other models from the literature available.

关键词： FRCM     deep neural networks     confinement effect     strength model     confined concrete    

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Confinement effects in methanol to olefins catalysed by zeolites: A computational review

German Sastre

《化学科学与工程前沿（英文）》 2016年 第10卷 第1期   页码 76-89 doi: 10.1007/s11705-016-1557-3

摘要： Small pore zeolites, containing 8-rings as the largest, are widely employed as catalysts in the process of methanol-to-olefins (MTO). Reactants and products diffuse with constraints through 8-rings and this is one of the reaction bottlenecks related to zeolite micropore topology. Small pore zeolites and silicon-aluminophosphates(SAPOs) containing cavities, where olefins are mainly formed through the hydrocarbon pool (HP) mechanism, are frequently tested for MTO. Shape selectivity of transition states within the side-chain methylation will be reviewed as this is one of the controlling steps of the MTO process, with particular attention to the role of hexamethylbenzene (HMB) and heptamethylbenzenium cation (HeptaMB ), which are the most tipically detected reaction intermediates, common to the paring and side-chain routes within the HP mechanism. The relative stability of these and other species will be reviewed in terms of confinement effects in different cage-based zeolites. The role of the different alkylating agents, methanol, dimethyl ether (DME), and surface methoxy species (SMS) will also be reviewed from the computational viewpoint.

关键词： small pore zeolites     SAPOs     methanol-to-olefins     hydrocarbon pool mechanism     alkylation of polymethylbenzenes    

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Engineering the electronic and geometric structure of VO/BN@TiO heterostructure for efficient aerobic oxidative desulfurization

《化学科学与工程前沿（英文）》 2023年 第17卷 第3期   页码 276-287 doi: 10.1007/s11705-022-2242-3

摘要： Particle size governs the electronic and geometric structure of metal nanoparticles (NPs), shaping their catalytic performances in heterogeneous catalysis. However, precisely controlling the size of active metal NPs and thereafter their catalytic activities remain an affordable challenge in ultra-deep oxidative desulfurization (ODS) field. Herein, a series of highly-efficient VOx/boron nitride nanosheets (BNNS)@TiO2 heterostructures, therein, cetyltrimethylammonium bromide cationic surfactants serving as intercalation agent, BNNS and MXene as precursors, with various VOx NP sizes were designed and controllably constructed by a facile intercalation confinement strategy. The properties and structures of the prepared catalysts were systematically characterized by different technical methods, and their catalytic activities were investigated for aerobic ODS of dibenzothiophene (DBT). The results show that the size of VOx NPs and V5+/V4+ play decisive roles in the catalytic aerobic ODS of VOx/BNNS@TiO2 catalysts and that VOx/BNNS@TiO2-2 exhibits the highest ODS activity with 93.7% DBT conversion within 60 min under the reaction temperature of 130 °C and oxygen flow rate of 200 mL·min–1, which is due to its optimal VOx dispersion, excellent reducibility and abundant active species. Therefore, the finding here may contribute to the fundamental understanding of structure-activity in ultra-deep ODS and inspire the advancement of highly-efficient catalyst.

关键词： oxidative desulfurization     boron nitride     vanadium     MXene     intercalation confinement    

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Innovative hybrid reinforcement constituting conventional longitudinal steel and FRP stirrups for improved seismic strength and ductility of RC structures

Mostafa FAKHARIFAR,Ahmad DALVAND,Mohammad K. SHARBATDAR,Genda CHEN,Lesley SNEED

《结构与土木工程前沿（英文）》 2016年 第10卷 第1期   页码 44-62 doi: 10.1007/s11709-015-0295-9

摘要： The use of fiber reinforced polymer (FRP) reinforcement is becoming increasingly attractive in construction of new structures. However, the inherent linear elastic behavior of FRP materials up to rupture is considered as a major drawback under seismic attacks when significant material inelasticity is required to dissipate the input energy through hysteretic cycles. Besides, cost considerations, including FRP material and construction of pre-fabricated FRP configurations, especially for stirrups, and probable damage to epoxy coated fibers when transported to the field are noticeable issues. The current research has proposed a novel economical hybrid reinforcement scheme for the next generation of infrastructures implementing on-site fabricated FRP stirrups comprised of FRP sheets. The hybrid reinforcement consists of conventional longitudinal steel reinforcement and FRP stirrups. The key feature of the proposed hybrid reinforcement is the enhanced strength and ductility owing to the considerable confining pressure provided by the FRP stirrups to the longitudinal steel reinforcement and core concrete. Reinforced concrete beam specimens and beam-column joint specimens were tested implementing the proposed hybrid reinforcement. The proposed hybrid reinforcement, when compared with conventional steel stirrups, is found to have higher strength, stiffness, and energy dissipation. Design methods, structural behavior, and applicability of the proposed hybrid reinforcement are discussed in detail in this paper.

关键词： FRP     ductility     confinement     seismic     shear    

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Floret-like Fe–N nanoparticle-embedded porous carbon superstructures from a Fe-covalent triazine polymer boosting oxygen electroreduction

《化学科学与工程前沿（英文）》 2023年 第17卷 第5期   页码 525-535 doi: 10.1007/s11705-022-2232-5

摘要： Fe–Nx nanoparticles-embedded porous carbons with a desirable superstructure have attracted immense attention as promising catalysts for electrochemical oxygen reduction reaction. Herein, we employed Fe-coordinated covalent triazine polymer for the fabrication of Fe–Nx nanoparticle-embedded porous carbon nanoflorets (Fe/N@CNFs) employing a hypersaline-confinement-conversion strategy. Presence of tailored N types within the covalent triazine polymer interwork in high proportions contributes to the generation of Fe/N coordination and subsequent Fe–Nx nanoparticles. Owing to the utilization of NaCl crystals, the resultant Fe/N@CNF-800 which was generated by pyrolysis at 800 °C showed nanoflower structure and large specific surface area, which remarkably suppressed the agglomeration of high catalytic active sites. As expect, the Fe/N@CNF-800 exhibited unexpected oxygen reduction reaction catalytic performance with an ultrahigh half-wave potential (0.89 V vs. reversible hydrogen electrode), a dominant 4e– transfer approach and great cycle stability (> 92% after 100000 s). As a demonstration, the Fe/N-PCNF-800-assembled zinc–air battery delivered a high open circuit voltage of 1.51 V, a maximum peak power density of 164 mW·cm–2, as well as eminent rate performance, surpassing those of commercial Pt/C. This contribution offers a valuable avenue to exploit efficient metal nanoparticles-based carbon catalysts towards energy-related electrocatalytic reactions and beyond.

关键词： Fe–Nx nanoparticles     hypersaline-confinement conversion     floret-like carbon     covalent triazine polymers     oxygen reduction reaction    

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Efficient hydrothermal deoxygenation of methyl palmitate to diesel-like hydrocarbons on carbon encapsulated Ni–Sn intermetallic compounds with methanol as hydrogen donor

《化学科学与工程前沿（英文）》 2023年 第17卷 第2期   页码 139-155 doi: 10.1007/s11705-022-2217-4

摘要： Porous carbon-encapsulated Ni and Ni–Sn intermetallic compound catalysts were prepared by the one-pot extended Stöber method followed by carbonization and tested for in-situ hydrothermal deoxygenation of methyl palmitate with methanol as the hydrogen donor. During the catalyst preparation, Sn doping reduces the size of carbon spheres, and the formation of Ni–Sn intermetallic compounds restrain the graphitization, contributing to larger pore volume and pore diameter. Consequently, a more facile mass transfer occurs in carbon-encapsulated Ni–Sn intermetallic compound catalysts than in carbon-encapsulated Ni catalysts. During the in-situ hydrothermal deoxygenation, the synergism between Ni and Sn favors palmitic acid hydrogenation to a highly reactive hexadecanal that easily either decarbonylate to n-pentadecane or is hydrogenated to hexadecanol. At high reaction temperature, hexadecanol undergoes dehydrogenation–decarbonylation, generating n-pentadecane. Also, the C–C bond hydrolysis and methanation are suppressed on Ni–Sn intermetallic compounds, favorable for increasing the carbon yield and reducing the H2 consumption. The n-pentadecane and n-hexadecane yields reached 88.1% and 92.8% on carbon-encapsulated Ni3Sn2 intermetallic compound at 330 °C. After washing and H2 reduction, the carbon-encapsulated Ni3Sn2 intermetallic compound remains stable during three recycling cycles. This is ascribed to the carbon confinement that effectively suppresses the sintering and loss of metal particles under harsh hydrothermal conditions.

关键词： extended Stöber method     carbon encapsulated Ni–Sn intermetallic compounds     confinement     in-situ hydrothermal deoxygenation     hydrogenation     decarbonylation    

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Plasmonic Au nanoparticles supported on both sides of TiO2 hollow spheres for maximising photocatalytic activity under visible light

Jianwei Lu, Lan Lan, Xiaoteng Terence Liu, Na Wang, Xiaolei Fan

《化学科学与工程前沿（英文）》 2019年 第13卷 第4期   页码 665-671 doi: 10.1007/s11705-019-1815-2

摘要： A strategy of intensifying the visible light harvesting ability of anatase TiO hollow spheres (HSs) was developed, in which both sides of TiO HSs were utilised for stabilising Au nanoparticles (NPs) through the sacrificial templating method and convex surface-induced confinement. The composite structure of single Au NP yolk-TiO shell-Au NPs, denoted as Au@Au(TiO , was rendered and confirmed by the transmission electron microscopy analysis. Au@Au(TiO showed enhanced photocatalytic activity in the degradation of methylene blue and phenol in aqueous phase under visible light surpassing that of other reference materials such as Au(TiO by 77% and Au@P25 by 52%, respectively, in phenol degradation.

关键词： TiO2 hollow spheres     plasmonic Au nanoparticles     confinement     visible light     photocatalytic degradation    

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Analysis of effect of different construction methods of piles on the end effect on skin friction of piles

ZHOU Hongbo, CHEN Zhuchang

《结构与土木工程前沿（英文）》 2007年 第1卷 第4期   页码 458-463 doi: 10.1007/s11709-007-0062-7

摘要： Based on the comparative analysis of end effect on skin friction of displacement-pile (driven pile), the end effect on skin friction of bored pile is studied. The end effect on skin friction between driven pile and bored pile is different and the end effect on skin friction of bored pile is reduce of skin friction in the soil layer adjacent to the pile end. The degradation degree of skin friction is deduced with the increase of the distance from pile end. The concept of additional mud cake formed by the effect of cushion at the bottom of borehole during pouring concrete is introduced to explain the mechanism of end effect on skin friction of the bored pile. The test results of post-grouting piles indicate that the post-grouting technique is an effective way to improve the end effect on skin friction of bored pile.

关键词： distance     different     concept     additional     bottom    

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A review on different theoretical models of electrocaloric effect for refrigeration

《能源前沿（英文）》 2023年 第17卷 第4期   页码 478-503 doi: 10.1007/s11708-023-0884-6

摘要： The performance parameters for characterizing the electrocaloric effect are isothermal entropy change and the adiabatic temperature change, respectively. This paper reviews the electrocaloric effect of ferroelectric materials based on different theoretical models. First, it provides four different calculation scales (the first-principle-based effective Hamiltonian, the Landau-Devonshire thermodynamic theory, phase-field simulation, and finite element analysis) to explain the basic theory of calculating the electrocaloric effect. Then, it comprehensively reviews the recent progress of these methods in regulating the electrocaloric effect and the generation mechanism of the electrocaloric effect. Finally, it summarizes and anticipates the exploration of more novel electrocaloric materials based on the framework constructed by the different computational methods.

关键词： electrocaloric effect     effective Hamiltonian     phase-field modeling     different theoretical models    

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A new miniaturized engine based on thermomagnetic effect of magnetic fluids

Lujun ZHOU, Yimin XUAN, Qiang LI, Wenlei LIAN

《能源前沿（英文）》 2009年 第3卷 第2期   页码 160-166 doi: 10.1007/s11708-009-0018-9

摘要： A new engine system, essentially consisting of a permanent NdFeB magnet, a kerosene-based magnetic fluid and a rotor, is proposed based on the thermomagnetic effect of a temperature-sensitive magnetic fluid. The rotor was driven by the thermal convection of the magnetic fluid in the presence of a homogeneous external magnetic field. A digital camera was used to record the rotation speed of the rotor to investigate the performance of the engine system under varying conditions such as heat load, heat sink temperature, and magnetic field distribution. The peak angle velocity obtained for the rotor was about 2.1 rad/min. The results illustrate that the rotation speed of the rotor increases as the input heat load increases, or as the heat sink temperature decreases. The performance of the motor is considerably influenced by the magnetic field imposed. Therefore, the performance of such an engine can be controlled conveniently by changing the external magnetic field and/or the temperature distribution in the fluid.

关键词： magnetic fluid     thermomagnetic effect     engine    

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The cooperation effect of Ni and Pt in the hydrogenation of acetic acid

《化学科学与工程前沿（英文）》 2022年 第16卷 第3期   页码 397-407 doi: 10.1007/s11705-021-2076-4

摘要： The catalytic hydrogenation of carboxylic acid to alcohols is one of the important strategies for the conversion of biomass. Herein, a series of Ni-doped PtSn catalysts were prepared, characterized and studied in the hydrogenation of acetic acid. The Ni dopant has a strong interaction with Pt, which promotes the hydrogen adsorption, providing an activated hydrogen-rich environment for the hydrogenation. Meanwhile, the presence of Ni also improves the Pt dispersion, giving more accessible active sites for hydrogen activation. The cooperation of Pt and Ni significantly promotes the catalytic activity of the hydrogenation of acetic acid to ethanol. As a result, the catalyst with 0.1% Ni exhibits the best reaction activity, and its space time yield is twice as that of the PtSn/SiO2 catalyst. It provides a meaningful instruction on the catalyst design for the carboxylic acid hydrogenation.

关键词： acetic acid     ethanol     hydrogenation     Pt     Ni     cooperation effect    

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Direct energy rebound effect for road transportation in China

《工程管理前沿（英文）》   页码 597-611 doi: 10.1007/s42524-023-0276-y

摘要： The enhancement of energy efficiency stands as the principal avenue for attaining energy conservation and emissions reduction objectives within the realm of road transportation. Nevertheless, it is imperative to acknowledge that these objectives may, in part or in entirety, be offset by the phenomenon known as the energy rebound effect (ERE). To quantify the long-term EREs and short-term EREs specific to China’s road transportation, this study employed panel cointegration and panel error correction models, accounting for asymmetric price effects. The findings reveal the following: The long-term EREs observed in road passenger transportation and road freight transportation range from 13% to 25% and 14% to 48%, respectively; in contrast, the short-term EREs in road passenger transportation and road freight transportation span from 36% to 41% and 3.9% to 32%, respectively. It is noteworthy that the EREs associated with road passenger transportation and road freight transportation represent a partial rebound effect, falling short of reaching the magnitude of a counterproductive backfire effect. This leads to the inference that the upsurge in energy consumption within the road transportation sector cannot be solely attributed to advancements in energy efficiency. Instead, various factors, including income levels, the scale of commodity trade, and industrial structure, exert more substantial facilitating influences. Furthermore, the escalation of fuel prices fails to dampen the demand for energy services, whether in the domain of road passenger transportation or road freight transportation. In light of these conclusions, recommendations are proffered for the formulation of energy efficiency policies pertinent to road transportation.

关键词： road transportation     direct energy rebound effect     asymmetric price effects     panel data model    

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标题 作者 时间 类型 操作

Magnetic confinement fusion: a brief review

Chuanjun HUANG, Laifeng LI

期刊论文

Confinement properties of circular concrete columns wrapped with prefabricated textile-reinforced fine

期刊论文

Development of deep neural network model to predict the compressive strength of FRCM confined columns

Khuong LE-NGUYEN; Quyen Cao MINH; Afaq AHMAD; Lanh Si HO

期刊论文

Confinement effects in methanol to olefins catalysed by zeolites: A computational review

German Sastre

期刊论文

Engineering the electronic and geometric structure of VO/BN@TiO heterostructure for efficient aerobic oxidative desulfurization

期刊论文

Innovative hybrid reinforcement constituting conventional longitudinal steel and FRP stirrups for improved seismic strength and ductility of RC structures

Mostafa FAKHARIFAR,Ahmad DALVAND,Mohammad K. SHARBATDAR,Genda CHEN,Lesley SNEED

期刊论文

Floret-like Fe–N nanoparticle-embedded porous carbon superstructures from a Fe-covalent triazine polymer boosting oxygen electroreduction

期刊论文

Efficient hydrothermal deoxygenation of methyl palmitate to diesel-like hydrocarbons on carbon encapsulated Ni–Sn intermetallic compounds with methanol as hydrogen donor

期刊论文

Plasmonic Au nanoparticles supported on both sides of TiO2 hollow spheres for maximising photocatalytic activity under visible light

Jianwei Lu, Lan Lan, Xiaoteng Terence Liu, Na Wang, Xiaolei Fan

期刊论文

李浩然：基于同伴效应与网络效应的“气代煤〞改造决策研究（2020年7月11日）

2022年05月19日

会议视频

Analysis of effect of different construction methods of piles on the end effect on skin friction of piles

ZHOU Hongbo, CHEN Zhuchang

期刊论文

A review on different theoretical models of electrocaloric effect for refrigeration

期刊论文

A new miniaturized engine based on thermomagnetic effect of magnetic fluids

Lujun ZHOU, Yimin XUAN, Qiang LI, Wenlei LIAN

期刊论文

The cooperation effect of Ni and Pt in the hydrogenation of acetic acid

期刊论文

Direct energy rebound effect for road transportation in China

期刊论文