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Reflection on Development Strategy of Engineering Management Discipline in China

Ying-luo Wang

《工程管理前沿（英文）》 2014年第1卷第2期页码 218-224 doi: 10.15302/J-FEM-2014029

摘要： A large number of engineering management professionals are required to promote engineering management efficiency, but the existing engineering management training system has some gaps with economical and social development in China. Development of engineering management discipline has very important strategic significance in China. This paper explores the disciplinary characteristics of engineering management, and analyzes the developmental issues about education of engineering management discipline. Meanwhile, the paper also proposes that the construction for development strategy of China’s engineering management discipline should be accelerated in the following aspects: Theoretical system of engineering management must be built and methodology of engineering management needs to be explored and perfected; advantages of various universities should be fully expressed, to show their own characteristics with accurate and reasonable positioning; knowledge system of engineering management discipline must be organized and integrated; practical ability of engineering management professionals needs to be promoted; education level of engineering management discipline should be perfected and training objectives at various levels must be clarified; teaching methods and means have to be reformed.

关键词： engineering management disciplinary characteristics development strategy

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Major bridge projects——a multi-disciplinary approach

Klaus H. OSTENFELD, Erik Y. ANDERSEN

《结构与土木工程前沿（英文）》 2011年第5卷第4期页码 479-495 doi: 10.1007/s11709-011-0137-3

摘要： Modern bridge building is much more than concrete, steel and money. The overall socioeconomic impact, influence on people migration, traffic, use of primary materials, safety of construction impact on the environment, energy, risk scenarios, health, and most relevant now: climate and CO emissions, are among the parameters which enter into the decision process at the overall holistic conceptual level, the more detailed level of selection of bridge sites, and selection of bridge types as well as construction methods and selection of materials and products. The paper illustrates these dilemmas and illustrates by specific examples how this complicated decision process can be managed and structured in order to arrive at an overall satisfactory solution for design, construction and maintenance throughout the lifetime (life cycle) to these sometimes contradictory parameters and requirements.

关键词： bridges materials climate risk safety environment socioeconomics traffic CO₂ energy life cycle society aesthetics

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Recent progress in hydrodynamic characteristics research and application of annular centrifugal extractors

《化学科学与工程前沿（英文）》 2022年第16卷第6期页码 854-873 doi: 10.1007/s11705-022-2156-0

摘要： The annular centrifugal extractor (ACE) integrates mixing and separation. It has been widely used in many industrial fields because of its low residence time, compact structure, and high mass transfer efficiency. Most of the literature has focused on flow instabilities, flow visualization, and computational fluid dynamics simulations. More recently, research on hydrodynamic behavior and structural optimization has received widespread attention. With the development of ACE technology, applications have been broadened into several new areas. Hence, this paper reviews research progress regarding ACE in terms of hydrodynamic characteristics and the structural improvements. The latest applications covering hydrometallurgy, nuclear fuel reprocessing, bio-extraction, catalytic reaction, and wastewater treatment are presented. We also evaluate future work in droplet breakup and coalescence mechanisms, structural improvements specific to different process requirements, scaling-up methods, and stability and reliability after scaling-up.

关键词： annular centrifugal extractor hydrodynamic characteristics structure optimization the latest application

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Clinical characteristics and outcomes of biopsy-proven diabetic nephropathy

null

《医学前沿（英文）》 2017年第11卷第3期页码 386-392 doi: 10.1007/s11684-017-0574-z

摘要：

Kidney damage is common in patients with diabetes mellitus (DM). However, whether the type of kidney damage can be reliably diagnosed using clinical data alone remains unclear. Predictive factors for diabetic nephropathy (DN) outcomes are also poorly understood. In this study, the clinical manifestations of 111 cases of biopsy-proven DN were described, and the clinical and pathological parameters of patients with different DN outcomes were compared. Results showed that long DM duration (>10 years in 32.4% of patients), severe proteinuria (62.2%), and renal dysfunction (estimated glomerular filtration rate [eGFR]<60 mL/(min·1.73 m²)) (52.3%) did not accurately indicate whether the condition of these patients progressed to DN. Hematuria (48.6%) failed to specify either DN or nondiabetic renal disease. Diabetic retinopathy (78.4%) was a crucial complication in patients with DN. Kaplan–Meier analysis revealed that the renal survival of 53 patients who were diagnosed with DN and were followed up was not significantly associated with glomerular classification (P>0.05). Cox’s regression analysis demonstrated that renal survival time was significantly influenced by sex (b= 1.394, P= 0.038), hematuria (b= 0.036, P= 0.029), and eGFR (b= −0.039, P= 0.002) but was not significantly affected by age, 24 h urinary protein excretion, or glomerular classification (P>0.05). In conclusion, the clinical characteristics of DN vary, and renal biopsy is necessary to determine renal damage patterns. Sex, hematuria, and the eGFR may affect DN outcomes, whereas the glomerular classification may not.

关键词： diabetic nephropathy clinical characteristics renal biopsy outcomes

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Obesity in China: its characteristics, diagnostic criteria, and implications

null

《医学前沿（英文）》 2015年第9卷第2期页码 129-133 doi: 10.1007/s11684-015-0387-x

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Dynamic characteristics of molten droplets and hot particles falling in liquid pool

Liangxing LI, Weimin MA, Huixiong LI, Tingkuan CHEN,

《能源前沿（英文）》 2010年第4卷第2期页码 246-251 doi: 10.1007/s11708-009-0077-y

摘要： The dynamic characteristics of molten droplets and hot particles at the very beginning of their fall into coolant pools are presented. The falling course of a single droplet or a single hot particle was recorded by a high-speed camera and a curve of velocity . time was obtained. Emphasis was placed on the effects of the droplet’s size and temperature, the coolant’s temperature and properties, and the droplet’s physical properties on the moving behavior. The results for the all cases showed that the velocity of a falling droplet/particle decreased rapidly but rebounded shortly, at the beginning of droplet/particle falling in the coolant. Following such a V-shaped evolution in velocity, the droplet/particle slows down gradually to a comparatively steady velocity. An increase in either coolant temperature or droplet temperature results in a larger velocity variation in the “J-region”, but a smaller deceleration when it moves out of the “J-region”. The elevated volatility of a coolant leads to a steeper deceleration in the “J-region” and beyond. The bigger size of a particle leads to a greater velocity variation in the “J-region” and terminal velocity. A high melting point and thermal conductivity as well as lower heat capacity contribute to dramatic variation in the “J-region” and low terminal velocity.

关键词： dynamic characteristics molten droplets high-temperature particles fuel and coolant interactions

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null

《医学前沿（英文）》 2017年第11卷第3期页码 340-348 doi: 10.1007/s11684-017-0570-3

摘要：

In light of the rapid increase in the number of obesity incidences worldwide, obesity has become an independent risk factor for chronic kidney disease. Obesity-related glomerulopathy (ORG) is characterized by glomerulomegaly in the presence or absence of focal and segmental glomerulosclerosis lesions. IgM and complement 3 (C3) nonspecifically deposit in lesions without immune-complex-type deposits during ORG immunofluorescence. ORG-associated glomerulomegaly and focal and segmental glomerulosclerosis can superimpose on other renal pathologies. The mechanisms under ORG are complex, especially hemodynamic changes, inflammation, oxidative stress, apoptosis, and reduced functioning nephrons. These mechanisms synergize with obesity to induce end-stage renal disease. A slow increase of subnephrotic proteinuria (<3.5 g/d) is the most common clinical manifestation of ORG. Several treatment methods for ORG have been developed. Of these methods, renin–angiotensin–aldosterone system blockade and weight loss are proven effective. Targeting mitochondria may offer a novel strategy for ORG therapy. Nevertheless, more research is needed to further understand ORG.

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Combustion characteristics and kinetics of bio-oil

Ruixia ZHANG, Zhaoping ZHONG, Yaji HUANG

《化学科学与工程前沿（英文）》 2009年第3卷第2期页码 119-124 doi: 10.1007/s11705-009-0068-x

摘要： The combustion characteristics of bio-oils derived from rice husk and corn were studied by thermogravimetry analysis. According to the thermogravimetry (TG), differential thermogravimetry (DTG) and differential thermal analysis (DTA) curves of bio-oils in air and nitrogen atmosphere, we analyzed the combustion characteristics of different kinds of bio-oils in different atmospheres and worked out the combustion kinetics parameters of the bio-oil, providing reliable base data for the burning of bio-oil. The thermogravimetry indicated that the combustion process of bio-oil was divided into three stages. At the same time, the combustion process can be described by different order reaction models, and with the method of Coats-Redfern, the activation energy and frequency factor of different kinds of bio-oils were obtained.

关键词： bio-oil combustion characteristics combustion kinetics

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Study on combustion characteristics of blended coals

LI Yonghua, WANG Chunbo, CHEN Hongwei

《能源前沿（英文）》 2007年第1卷第1期页码 96-100 doi: 10.1007/s11708-007-0010-1

摘要： Power plants in China have to burn blended coal instead of one specific coal for a variety of reasons. So it is of great necessity to investigate the combustion of blended coals. Using a test rig with a capacity of 640 MJ/h with an absolute milling system and flue gas online analysis system, characteristics such as burnout, slag, and pollution of some blended coals were investigated. The ratio of coke and slag as a method of distinguishing coal slagging characteristic was introduced. The results show that the blending of coal has some effect on NO but there is no obvious rule. SO emission can be reduced by blending low sulfur coal.

关键词： combustion capacity variety blended burnout

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The strength–dilatancy characteristics embraced in hypoplasticity

Zhongzhi FU, Sihong LIU, Zijian WANG

《结构与土木工程前沿（英文）》 2013年第7卷第2期页码 178-187 doi: 10.1007/s11709-013-0191-0

摘要： The strength-dilatancy characteristics of frictional materials embraced in the hypoplastic model proposed by Gudehus and Bauer are investigated and compared with the revised model suggested by Huang. In the latter the deviatoric stress in the model by Gudehus and Bauer is replaced by a transformed stress according to the stress transformation technique proposed by Matsuoka. The flow rule, the failure state surface equation and the strength-dilatancy relationship embraced in both models are derived analytically. The performance of the two hypoplastic models in reproducing the relationship between the peak strength and the corresponding dilation rate under triaxial compression, plane compression and plane shearing are then extensively investigated and compared with experimental results and with the predictions made by particular classical stress-dilatancy theories. Numerical investigations show that the performance in reproducing the strength-dilatancy relationship is quite satisfactory under triaxial compression stress state in both models and the predictions made by the transformed stress based model are closer to the results obtained from classical stress-dilatancy theories for plane compression and plane shearing problems.

关键词： strength dilatancy hypoplasticity frictional materials

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Characteristics of two transferable aminoglycoside resistance plasmids in

Chengjun Pu, Xiaoyan Gong, Ying Sun

《环境科学与工程前沿（英文）》 2019年第13卷第3期 doi: 10.1007/s11783-019-1119-2

摘要：

pRKZ3 is a non-conjugative IncQ plasmid, while pKANJ7 is a conjugative IncX plasmid.

The optimal mating time of pKANJ7 varied under different conditions.

Both of the two transferable ARPs had little impact on the growth of their hosts.

A relatively high level of fitness cost was observed for pKANJ7.

The fitness cost of ARPs depended on their hosts.

关键词： Escherichia coli Characteristics Aminoglycoside resistance plasmids Transfer Persistence

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Combustion effects and emission characteristics of SO

Yiying JIN,Yangyang LI,Fuqiang LIU

《环境科学与工程前沿（英文）》 2016年第10卷第1期页码 201-210 doi: 10.1007/s11783-014-0739-9

摘要： The influences of dewatered sludge blending ratio in coal on flammability index (C) and combustion characteristic index (S) and release of sulfur dioxide (SO ), nitrogen oxide (NO ), carbon monoxide (CO) and heavy metals (Hg, As, Cd, Pb and Cr) were studied. The impact on combustion characteristics could be ignored if less than 20% of dewatered sludge was added in coal. Besides, emission pattern experiments of NO , SO , CO and heavy metals were carried out in a high-temperature tubular furnace. Results showed that the conversion rate of NO and total emission of SO reduced with the increase of sludge adding ratio, and a better effect of fixing sulfur could be obtained when the blending ratio reached 30%. Concentrations and distributions of five types of heavy metals in different residues (bottom ash and fly ash) as well as in flue gas were analyzed. It was shown that the characteristics of coal and sludge, as well as the volatilization of heavy metals had a great influence on the distribution of heavy metals.

关键词： sewage sludge combustion characteristic coal emission heavy metals

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Experimental investigations on operating characteristics of a closed loop pulsating heat pipe

Yu WANG

《能源前沿（英文）》 2015年第9卷第2期页码 134-141 doi: 10.1007/s11708-015-0354-x

摘要： The operating mechanism of the pulsating heat pipe (PHP) is not well understood and the present technology cannot predict required design parameters for a given task. The aim of research work presented in this paper is to better understand the operation regimes of the PHP through experimental investigations. A series of experiments were conducted on a closed loop PHP with 5 turns made of copper capillary tube of 2 mm in inner diameter. Two different working fluids viz. ethanol and acetone were employed. The operating characteristics were studied for the variation of heat input, filling ratio (FR) and inclination angle of the tested device. The results strongly demonstrate the effect of the filling ratio of the working fluid on the operational stability and heat transfer capability of the device. Important insight into the operational characteristics of PHP has been obtained.

关键词： closed loop pulsating heat pipe thermal performance operation limit thermography

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Heat transfer characteristics of high heat flux vapor chamber

Dongchuan MO, Shushen LU, Haoliang ZHENG, Chite CHIN,

《能源前沿（英文）》 2010年第4卷第2期页码 166-170 doi: 10.1007/s11708-009-0076-z

摘要： To meet the challenge of heat spreading in electronic products, highly efficient high heat flux heat transfer vapor chambers have been manufactured and their heat transfer characteristics have been studied by a fast test system. A solid copper block with the same shape as the vapor chamber is used to compare the performance of the vapor chamber. The result shows that, it will take about 5min to achieve a steady state in the fast test system. The heat transfer characteristics of the vapor chamber are more superior to those of the copper block. In this paper, total thermal resistance of the test system is used to evaluate the heat transfer characteristics of the vapor chamber, because it has already been used to consider both the spreading thermal resistance and the flatness of the vapor chamber.

关键词： high heat flux vapor chamber (VC) heat transfer characteristics fast test

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Acoustic characteristics of bi-directional turbines for thermoacoustic generators

Dongdong LIU, Yanyan CHEN, Wei DAI, Ercang LUO

《能源前沿（英文）》 2022年第16卷第6期页码 1027-1036 doi: 10.1007/s11708-020-0702-3

摘要： Bi-directional turbines combined with rotary motors may be a feasible option for developing high power thermoacoustic generators with low cost. A general expression for the acoustic characteristics of the bi-directional turbine was proposed based on theoretical derivation, which was validated by computational fluid dynamics modeling of an impulse turbine with fixed guide vanes. The structure of the turbine was optimized primarily using steady flow with an efficiency of near 70% (the shaft power divided by the total energy consumed by the turbine). The turbine in the oscillating flow was treated in a lumped-parameter model to extract the acoustic impedance characteristics from the simulation results. The key acoustic impedance characteristic of the turbine was the resistance and inertance due to complex flow condition in the turbine, whereas the capacitance was treated as an adiabatic case because of the large-scale flow channel relative to the heat penetration depth. Correlations for the impedance were obtained from both theoretical predictions and numerical fittings. The good fit of the correlations shows that these characteristics are valid for describing the bi-directional turbine, providing the basis for optimization of the coupling between the thermoacoustic engine and the turbine using quasi-one-dimensional theory in the frequency domain.

关键词： thermoacoustic power generator acoustic characteristics bi-directional impulse turbine energy conversion