资源类型

期刊论文 241

年份

2024 1

2023 20

2022 18

2021 23

2020 18

2019 7

2018 8

2017 7

2016 12

2015 7

2014 7

2013 9

2012 12

2011 11

2010 14

2009 10

2008 14

2007 11

2006 8

2005 9

展开 ︾

关键词

临界风速 2

快子 2

柔性机器人 2

液体燃料 2

超光速 2

300 M钢 1

N-糖组 1

ADV 1

CCD影像 1

CO2 加氢 1

Chebyshev多项式 1

EFP 1

GH位移 1

Hilare 机器人 1

Maxwell方程组 1

N-聚糖 1

PIV 1

Proca方程组 1

TOC 1

展开 ︾

检索范围:

排序: 展示方式:

CFD simulation of the hydrodynamics in an internal air-lift reactor with two different configurations

Mona EBRAHIMIFAKHAR, Elmira MOHSENZADEH, Sadegh MORADI, Mostafa MORAVEJI, Mahmoud SALIMI

《化学科学与工程前沿(英文)》 2011年 第5卷 第4期   页码 455-462 doi: 10.1007/s11705-011-1116-x

摘要: Computational fluid dynamics (CFD) was used to investigate the hydrodynamic parameters of two internal airlift bioreactors with different configurations. Both had a riser diameter of 0.1 m. The model was used to predict the effect of the reactor geometry on the reactor hydrodynamics. Water was utilized as the continuous phase and air in the form of bubbles was applied as the dispersed phase. A two-phase flow model provided by the bubbly flow application mode was employed in this project. In the liquid phase, the turbulence can be described using the - model. Simulated gas holdup and liquid circulation velocity results were compared with experimental data. The predictions of the simulation are in good agreement with the experimental data.

关键词: airlift reactor     gas holdup     liquid circulation velocity     bubbly flow     computational fluid dynamics (CFD)    

Simulation of flow excursion and thermal siphon under natural circulation condition with lower pressure

WANG Jianjun, YANG Xingtuan, JIANG Shengyao

《能源前沿(英文)》 2008年 第2卷 第2期   页码 169-173 doi: 10.1007/s11708-008-0044-z

摘要: The simulation of flow excursion was conducted under HRTL-5 condition. The mechanism analysis and the simulation of thermal siphon process were also performed. The result shows that the computer code can be used to simulate the static instability of a natural circulation system and the simulation of flow excursion almost conforms to the experiment result.

关键词: HRTL-5     experiment     circulation     simulation     thermal    

“双循环”背景下国家粮食安全战略研究

闫琰,王秀东,王济民,梅旭荣,唐华俊,吴孔明

《中国工程科学》 2023年 第25卷 第4期   页码 14-25 doi: 10.15302/J-SSCAE-2023.04.001

摘要: Academy of Engineering project “Research on National Grain Security Strategy in the Context of Dual Circulation

关键词: 双循环;粮食安全;粮食产能;绿色低碳;种养循环;新型蛋白饲料    

Prediction of the shear wave velocity

Amoroso SARA

《结构与土木工程前沿(英文)》 2014年 第8卷 第1期   页码 83-92 doi: 10.1007/s11709-013-0234-6

摘要: The paper examines the correlations to obtain rough estimates of the shear wave velocity from non-seismic dilatometer tests (DMT) and cone penetration tests (CPT). While the direct measurement of is obviously preferable, these correlations may turn out useful in various circumstances. The experimental results at six international research sites suggest that the DMT predictions of from the parameters (material index), (horizontal stress index), (constrained modulus) are more reliable and consistent than the CPT predictions from (cone resistance), presumably because of the availability, by DMT, of the stress history index .

关键词: horizontal stress index     shear wave velocity     flat dilatometer test     cone penetration test    

基于循环经济的企业发展战略创新研究

王孝斌,王学军

《中国工程科学》 2006年 第8卷 第6期   页码 89-91

摘要:

循环经济走新型工业化道路、实现可持续发展的有效途径。讨论了企业发展循环经济应重新审视和调整发展战略,在观念、组织、管理、制度、技术、产品等方面要有所创新的问题。

关键词: 资源     循环经济     创新     企业    

Chemical probe systems for assessing liquidliquid mixing efficiencies of reactors

《化学科学与工程前沿(英文)》 2023年 第17卷 第10期   页码 1323-1335 doi: 10.1007/s11705-022-2275-7

摘要: Liquid–liquid mixing, including homogeneous and heterogeneous mixing, widely exists in the chemical industry. How to quantitatively characterize the mixing performance is important for reactor assessment and development. As a convenient and direct method for mixing characterization, the chemical probe method uses some special test reactions to characterize the mixing results. Here, the working principle and selection requirements of this method are introduced, and some common chemical probe systems for homogeneous and heterogeneous mixing processes are reviewed. The characteristics and applications of these systems are illustrated. Finally, the development of the new system is proposed.

关键词: mixing     chemical probe     liquid–liquid     heterogeneous    

Simulation analysis of methanol flash distillation circulation process in biodiesel production with supercritical

Zhengjiao TANG, Cunwen WANG, Weiguo WANG, Jia GUO, Yuanxin WU, Jinfang CHEN, Yigang DING

《能源前沿(英文)》 2011年 第5卷 第1期   页码 93-97 doi: 10.1007/s11708-010-0028-7

摘要: High methanol-to-oil ratio is required to obtain a high conversion of oil for the production of biodiesel with supercritical methanol. Recovering the methanol of a stream issuing from a transesterification supercritical reactor by flash distillation instead of evaporation was analyzed. The one-stage and two-stage flash distillation processes were presented and compared. The difference of the recovery percentage of methanol of the above two flash processes is less than 0.5% and the methanol concentration in the vapor for the one-stage process decreases rapidly when feed temperature increases. The process in which the product of transesterification of soybean oil with supercritical methanol is cooled to an appropriate temperature (about 240°C) first and then flashed was put forward. The effect of cooling temperature, feed pressure and flash pressure on methanol concentration and recovery percentage was investigated. According to this study, when the feed pressure range is 15–30 MPa, the flash pressure equals 0.4 MPa, and cooling temperature range is 240°C–250°C, the recovery percentage of methanol is not less than 85%, and the concentration of the vapor in mass fraction of methanol is approximately 99%. Thus, the vapor leaving the flash tank can be directly circulated to the transesterification reactor.

关键词: supercritical methanol     biodiesel     recovery     flash distillation    

“双循环”新格局下我国食品营养与健康产业发展策略研究

刘泽龙,李健,王静,孙宝国

《中国工程科学》 2022年 第24卷 第6期   页码 72-80 doi: 10.15302/J-SSCAE-2022.06.007

摘要:

食品营养与健康产业是“双循环”新发展格局下实施健康中国战略的重要构成。本文梳理了食品营养与健康产业的发展态势,分析了“双循环”新格局下产业发展面临的挑战以及新格局对产业发展的影响。依据国家整体布局和规划,分别从立足“内循环”构建基于我国国民健康基础信息的食品产业技术体系、以产业多元化发展促进“内外双循环”、利用好“两个市场、两种资源”提升产业影响力等角度提出了突破路径。研究建议:注重食品营养与健康领域创新资源投入,加快高质量成果产出;加强政策扶植引导,增强企业国际竞争力;完善“产学研”协同体系,促进成果转化;加大人才培养力度,提供专业人才支撑;完善行业监管体制,营造健康市场环境;加强食品营养与健康教育宣传,提升公民健康素养。

关键词: 食品营养与健康;产业发展;“双循环”;产业多元化    

High velocity impact of metal sphere on thin metallic plate using smooth particle hydrodynamics (SPH)

Hossein ASADI KALAMEH, Arash KARAMALI, Cosmin ANITESCU, Timon RABCZUK

《结构与土木工程前沿(英文)》 2012年 第6卷 第2期   页码 101-110 doi: 10.1007/s11709-012-0160-z

摘要: The modeling of high velocity impact is an important topic in impact engineering. Due to various constraints, experimental data are extremely limited. Therefore, detailed numerical simulation can be considered as a desirable alternative. However, the physical processes involved in the impact are very sophisticated; hence a practical and complete reproduction of the phenomena involves complicated numerical models. In this paper, we present a smoothed particle hydrodynamics (SPH) method to model two-dimensional impact of metal sphere on thin metallic plate. The simulations are applied to different materials (Aluminum, Lead and Steel); however the target and projectile are formed of similar metals. A wide range of velocities (300, 1000, 2000, and 3100 m/s) are considered in this study. The goal is to study the most sensitive input parameters (impact velocity and plate thickness) on the longitudinal extension of the projectile, penetration depth and damage crater.

关键词: smoothed particle hydrodynamics     high velocity impact     sensitivity analysis    

Experimental study on velocity characteristics of recirculation zone in humid air non-premixed flame

GU Xin, ZANG Shusheng, GE Bing

《能源前沿(英文)》 2008年 第2卷 第2期   页码 140-144 doi: 10.1007/s11708-008-0037-y

摘要: To examine the effect of the flow field within the recirculation zone on flame structure, the characteristic velocity fields of methane/humid air flame in non-premixed combustion behind a disc bluff-body burner were experimentally studied by particle image velocimeter (PIV).The results show that two stagnation points exist on the centerline in the recirculation zone flame. However, the distance of the two stagnation points in humid air combustion shortens, and the minimal dimensionless velocity increases compared with the conventional non-humid air combustion. In addition, the positional curves of the minimal velocities can be partitioned into three phases representing three different flame patterns. The analysis of axial minimal velocities on the centerline and their positions under different co-flow air velocity conditions reveals that fuel-to-air velocity ratio is the crucial parameter that governs humid air combustion flame characteristics.

关键词: distance     bluff-body     fuel-to-air velocity     stagnation     parameter    

Microfluidic production of liposomes through liquidliquid phase separation in ternary droplets

《化学科学与工程前沿(英文)》 2022年 第16卷 第6期   页码 1017-1022 doi: 10.1007/s11705-021-2118-y

摘要: Liposomes, the self-assembled phospholipid vesicles, have been extensively used in various fields such as artificial cells, drug delivery systems, biosensors and cosmetics. However, current microfluidic routes to liposomes mostly rely on water-in-oil-in-water double emulsion droplets as templates, and require complex fabrication of microfluidic devices, and tedious manipulation of multiphase fluids. Here we present a simple microfluidic approach to preparing monodisperse liposomes from oil-in-water droplets. For demonstration, we used butyl acetate-water-ethanol ternary mixtures as inner phase and an aqueous solution of surfactants as outer phase to make oil-in-water droplets, which can evolve into water-in-oil-in-water double emulsion droplets by liquid–liquid phase separation of ternary mixtures. Subsequently, the resultant water-in-oil-in-water droplets underwent a dewetting transition to form separated monodisperse liposomes and residual oil droplets, with the assistance of surfactants. The method is simple, does not require complex microfluidic devices and tedious manipulation, and provides a new platform for controllable preparation of liposomes.

关键词: microfluidics     liposomes     ternary droplets     phase separation    

definition of metabolic dysfunction-associated fatty liver disease with elevated brachial-ankle pulse wave velocity

《医学前沿(英文)》 2022年 第16卷 第5期   页码 714-722 doi: 10.1007/s11684-021-0888-8

摘要: A new definition of metabolic dysfunction-associated fatty liver disease (MAFLD) has recently been proposed. We aim to examine the associations of MAFLD, particularly its discordance from non-alcoholic fatty liver disease (NAFLD), with the progression of elevated brachial-ankle pulse wave velocity (baPWV) and albuminuria in a community-based study sample in Shanghai, China. After 4.3 years of follow-up, 778 participants developed elevated baPWV and 499 developed albuminuria. In comparison with the non-MAFLD group, the multivariable adjusted odds ratio (OR) of MAFLD group for new-onset elevated baPWV was 1.25 (95% confidence interval (CI) 1.01–1.55) and 1.35 (95% CI 1.07–1.70) for albuminuria. Participants without NAFLD but diagnosed according to MAFLD definition were associated with higher risk of incident albuminuria (OR 1.77; 95% CI 1.07–2.94). Patients with MAFLD with high value of hepamet fibrosis score or poor-controlled diabetes had higher risk of elevated baPWV or albuminuria. In conclusion, MAFLD was associated with new-onset elevated baPWV and albuminuria independently of body mass index, waist circumference, and hip circumference. Individuals without NAFLD but diagnosed as MAFLD had high risk of albuminuria, supporting that MAFLD criteria would be practical for the evaluation of long-term risk of subclinical atherosclerosis among fatty liver patients.

关键词: metabolic dysfunction-associated fatty liver disease     non-alcoholic fatty liver disease     fibrosis score     brachial-ankle pulse wave velocity     albuminuria    

Energy distribution between liquid hydrogen and liquid oxygen temperatures in a Stirling/pulse tube refrigerator

《能源前沿(英文)》 2023年 第17卷 第4期   页码 516-526 doi: 10.1007/s11708-022-0844-6

摘要: A two-stage gas-coupled Stirling/pulse tube refrigerator (SPR), whose first and second stages respectively involve Stirling and pulse tube refrigeration cycles, is a very promising spaceborne refrigerator. The SPR has many advantages, such as a compact structure, high reliability, and high performance, and is expected to become an essential refrigerator for space applications. In research regarding gas-coupled regenerative refrigerator, the energy flow distribution between the two stages, and optimal phase difference between the pressure wave and volume flow, are two critical parameters that could widely influence refrigerator performance. The effects of displacer displacement on the pressure wave, phase difference, acoustic power distribution, and inter-stage cooling capacity shift of the SPR have been investigated experimentally. Notably, to obtain the maximum first-stage cooling capacity, an inflection point in displacement exists. When the displacer displacement is larger than the inflection point, the cooling capacity could be distributed between the first and second stages. In the present study, an SPR was designed and manufactured to work between the liquid hydrogen and liquid oxygen temperatures, which can be used to cool small-scale zero boil-off systems and space detectors. Under appropriate displacer displacement, the SPR can reach a no-load cooling temperature of 15.4 K and obtain 2.6 W cooling capacity at 70 K plus 0.1 W cooling capacity at 20 K with 160 W compressor input electric power.

关键词: Stirling/pulse tube refrigerator     displacer displacement     space application     phase shift     energy distribution    

Theoretical study of failure in composite pressure vessels subjected to low-velocity impact and internal

Roham RAFIEE, Hossein RASHEDI, Shiva REZAEE

《结构与土木工程前沿(英文)》 2020年 第14卷 第6期   页码 1349-1358 doi: 10.1007/s11709-020-0650-3

摘要: A theoretical solution is aimed to be developed in this research for predicting the failure in internally pressurized composite pressure vessels exposed to low-velocity impact. Both in-plane and out-of-plane failure modes are taken into account simultaneously and thus all components of the stress and strain fields are derived. For this purpose, layer-wise theory is employed in a composite cylinder under internal pressure and low-velocity impact. Obtained stress/strain components are fed into appropriate failure criteria for investigating the occurrence of failure. In case of experiencing any in-plane failure mode, the evolution of damage is modeled using progressive damage modeling in the context of continuum damage mechanics. Namely, mechanical properties of failed ply are degraded and stress analysis is performed on the updated status of the model. In the event of delamination occurrence, the solution is terminated. The obtained results are validated with available experimental observations in open literature. It is observed that the sequence of in-plane failure and delamination varies by increasing the impact energy.

关键词: composite pressure vessel     low-velocity impact     failure     theoretical solution     progressive damage modeling    

Studies on the liquid-liquid interfacial mass transfer process using holographic interferometry

ZHAO Chaofan, ZHU Chunying, MA Youguang

《化学科学与工程前沿(英文)》 2008年 第2卷 第1期   页码 1-4 doi: 10.1007/s11705-008-0006-3

摘要: This paper aims at the interfacial phenomena of liquid-liquid mass transfer and its characteristic. By using the real-time holographic technique, the concentration distributions on the aqueous side were obtained according to holographic diagrams of mass transfer of ethanol through the interface of oil and water at different initial concentrations. Furthermore, the concentrations near the interface and the mass transfer coefficients were attained. A correlation of concentration near the interface to the concentration of the solute in the oil side was proposed. An approach of interfacial energy with solute concentration was established, and the calculated results are at good agreement with the experimental data. It is indicated that the liquid-liquid mass transfer process is approximately in accordance with two-film theory, the interfacial performance may be changed by the addition of the solute, and the interface of liquid-liquid is non-equilibrium thermodynamically during the mass transfer process.

关键词: liquid-liquid     different     real-time holographic     addition     transfer    

标题 作者 时间 类型 操作

CFD simulation of the hydrodynamics in an internal air-lift reactor with two different configurations

Mona EBRAHIMIFAKHAR, Elmira MOHSENZADEH, Sadegh MORADI, Mostafa MORAVEJI, Mahmoud SALIMI

期刊论文

Simulation of flow excursion and thermal siphon under natural circulation condition with lower pressure

WANG Jianjun, YANG Xingtuan, JIANG Shengyao

期刊论文

“双循环”背景下国家粮食安全战略研究

闫琰,王秀东,王济民,梅旭荣,唐华俊,吴孔明

期刊论文

Prediction of the shear wave velocity

Amoroso SARA

期刊论文

基于循环经济的企业发展战略创新研究

王孝斌,王学军

期刊论文

Chemical probe systems for assessing liquidliquid mixing efficiencies of reactors

期刊论文

Simulation analysis of methanol flash distillation circulation process in biodiesel production with supercritical

Zhengjiao TANG, Cunwen WANG, Weiguo WANG, Jia GUO, Yuanxin WU, Jinfang CHEN, Yigang DING

期刊论文

“双循环”新格局下我国食品营养与健康产业发展策略研究

刘泽龙,李健,王静,孙宝国

期刊论文

High velocity impact of metal sphere on thin metallic plate using smooth particle hydrodynamics (SPH)

Hossein ASADI KALAMEH, Arash KARAMALI, Cosmin ANITESCU, Timon RABCZUK

期刊论文

Experimental study on velocity characteristics of recirculation zone in humid air non-premixed flame

GU Xin, ZANG Shusheng, GE Bing

期刊论文

Microfluidic production of liposomes through liquidliquid phase separation in ternary droplets

期刊论文

definition of metabolic dysfunction-associated fatty liver disease with elevated brachial-ankle pulse wave velocity

期刊论文

Energy distribution between liquid hydrogen and liquid oxygen temperatures in a Stirling/pulse tube refrigerator

期刊论文

Theoretical study of failure in composite pressure vessels subjected to low-velocity impact and internal

Roham RAFIEE, Hossein RASHEDI, Shiva REZAEE

期刊论文

Studies on the liquid-liquid interfacial mass transfer process using holographic interferometry

ZHAO Chaofan, ZHU Chunying, MA Youguang

期刊论文