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A novel light fluctuation spectrum method for in-line particle sizing

Shouxuan QIN, Xiaoshu CAI, Li MA

《能源前沿（英文）》 2012年 第6卷 第1期   页码 89-97 doi: 10.1007/s11708-012-0176-z

摘要： This paper discusses two problems in in-line particle sizing when using light fluctuation method. First, by retrieving the ratio of particle concentrations at different time, the intensity of incident light is obtained. There exists narrow error between the calculated and pre-detected value of the intensity of incident light. Secondly, by combining spectrum analysis with Gregory’s theory, a multi-sub-size zone model is proposed, with which the relationship between the distribution of turbidity and the particle size distribution (PSD) can be established, and an algorithm developed to determine the distribution of turbidity. Experiments conducted in the laboratory indicate that the measured size distribution of pulverized coal conforms well with the imaging result.

关键词： in-line measurement     particle size distribution (PSD)     incident light intensity     particle concentration     light fluctuation    

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Fluorene-based narrow-band-gap copolymers for red light-emitting diodes and bulk heterojunction photovoltaic

SUN Mingliang, WANG Li, XIA Yangjun, DU Bin, LIU Ransheng, CAO Yong

《化学科学与工程前沿（英文）》 2008年 第2卷 第3期   页码 257-264 doi: 10.1007/s11705-008-0052-x

摘要： A series of narrow band-gap conjugated copolymers (PFO-DDQ) derived from 9,9-dioctylfluorene (DOF) and 2,3-dimethyl-5,8-dithien-2-yl-quinoxalines (DDQ) is prepared by the palladium-catalyzed Suzuki coupling reaction with the molar feed ratio of DDQ at around 1%, 5%, 15%, 30% and 50%, respectively. The obtained polymers are readily soluble in common organic solvents. The solutions and the thin solid films of the copolymers absorb light from 300–590 nm with two absorbance peaks at around 380 and 490 nm. The intensity of 490 nm peak increases with the increasing DDQ content in the polymers. Efficient energy transfer due to exciton trapping on narrow-band-gap DDQ sites has been observed. The PL emission consists exclusively of DDQ unit emission at around 591–643 nm depending on the DDQ content in solid film. The EL emission peaks are red-shifted from 580 nm for PFO-DDQ1 to 635 nm for PFO-DDQ50. The highest external quantum efficiency achieved with the device configuration ITO/PEDOT/PVK/PFO-DDQ15/Ba/Al is 1.33% with a luminous efficiency 1.54 cd/A. Bulk heterojunction photovoltaic cells fabricated from composite films of PFO-DDQ30 copolymer and [6,6]-phenyl C butyric acid methyl ester (PCBM) as electron donor and electron acceptor, respectively in device configuration: ITO/PEDOT:PSS/PFO-DDQ30:PCBM/PFPNBr/Al shows power conversion efficiencies of 1.18% with open-circuit voltage () of 0.90 V and short-circuit current density () of 2.66 mA/cm under an AM1.5 solar simulator (100 mW/cm). The photocurrent response wavelengths of the PVCs based on PFO-DDQ30/PCBM blends covers 300–700 nm. This indicates that these kinds of low band-gap polymers are promising candidates for polymeric solar cells and red light-emitting diodes.

关键词： simulator     Efficient     band-gap     PFO-DDQ50     intensity    

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On subsurface box-shaped lined tunnel under incident SH-wave propagation

《结构与土木工程前沿（英文）》 2021年 第15卷 第4期   页码 948-960 doi: 10.1007/s11709-021-0740-x

摘要： In this paper, a half-plane time-domain boundary element method is applied to obtain the seismic ground response, including a subsurface box-shaped lined tunnel deployed in a linear homogenous elastic medium exposed to obliquely incident SH-waves. Only the boundary around the tunnel is required to be discretized. To prepare an appropriate model by quadratic elements, a double-node procedure is used to receive dual boundary fields at corners as well as change the direction of the normal vector. After encoding the method in a previously confirmed computer program, a numerical study is carried out to sensitize some effective parameters, including frequency content and incident wave angle for obtaining a surface response. The depth and impedance ratio of the lining are assumed to be unvaried. The responses are illustrated in the time and frequency domains as two/three-dimensional graphs. The results showed that subsurface openings with sharp corners distorted the propagation path of the anti-plane waves to achieve the critical states on the ground surface. The present approach can be proposed to civil engineers for preparing simple underground box-shaped models with angular boundaries.

关键词： box-lined tunnel     half-plane BEM     surface response     SH-wave     time-domain    

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Influence of sprinkler irrigation droplet diameter, application intensity and specific power on flower

Yisheng ZHANG, Delan ZHU

《农业科学与工程前沿（英文）》 2017年 第4卷 第2期   页码 165-171 doi: 10.15302/J-FASE-2017145

摘要： To determine the main parameters of droplet strike damage and avoid flower injury due to the unsuitable practices during sprinkler irrigation, an indoor experiment of irrigation droplet impact on cyclamen was conducted. The influences of different parameters such as droplet diameter, application intensity, specific power on flower strike damage was analyzed using Image Pro-Plus software to compute strike damage area and define damage level by sense-analysis. The results showed that a damage area of <1% represents a safe irrigation level, 1%–3% slight damage level, 3%–6% moderate damage level, and>6% heavy damage level. Equations of application intensity, specific power with sprinkler irrigation time and flower injury ratio were regressed against parameters which cause impact damages. The results indicated that specific power has a significant correlation with injury, and flower damage area increased as the increasing of the value of specific power for the same irrigation time. Application intensity was also correlated with injury when the droplet diameter was larger than 1 mm. When the duration of sprinkler irrigation was 1, 5 and 10 min, the threshold of impinging damage of application intensity was 25.30, 5.01 and 1.64 mm·h and the specific power was 0.467×10 , 9.340×10 and 3.110×10 W·m . These results provide a reference for determining the suitable values of sprinkler properties in operation design.

关键词： application intensity     damage     floriculture     flowers     specific power     sprinkler irrigation    

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Impact of inter-fuel substitution on energy intensity in Ghana

Boqiang LIN, Hermas ABUDU

《能源前沿（英文）》 2020年 第14卷 第1期   页码 27-41 doi: 10.1007/s11708-019-0656-5

摘要： Energy intensity and elasticity, together with inter-fuel substitution are key issues in the current development stage of Ghana. Translog production and ridge regression are applied for studying these issues with a data range of 2000–2015. The current energy dynamics reveal the expected inverse relationship: higher energy intensity and lower elasticity with economic growth. There are evidences of energy-economic challenges: high energy cost, inefficiency and backfire rebound effect. The implications are higher energy losses in the system, more consumption of lower-quality energy together with low energy technology innovation. Energy is wasted and directly not productive with economic activities. It is observed further that the higher energy intensity invariably increases CO emission because approximately 95% of total energy is derived from hydrocarbons and biomass. An inter-fuel substitution future scenario design was further conducted and the results were positive with growth, lower energy intensity, and improved energy efficiency. Therefore, government and energy policymakers should improve energy efficiency, cost, and productiveness. That is, they should change energy compositions and augment energy technology innovation, thus, increasing renewable share to 15% by 2026, reducing wood and charcoal by about 69%, and increasing natural gas to about 776%. Energy policymakers should enhance the installation of smart energy, cloud energy solution, tokenization of energy system and storage.

关键词： energy intensity     energy elasticity     inter-fuel substitution prospects     energy contribution     Translog production approach     ridge regression    

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Soil seismic analysis for 2D oblique incident waves using exact free-field responses by frequency-based

《结构与土木工程前沿（英文）》 2022年 第16卷 第12期   页码 1530-1551 doi: 10.1007/s11709-022-0900-7

摘要： The seismic analysis of a viscoelastic half-space under two-dimensional (2D) oblique incident waves is carried out by the finite/infinite element method (FIEM). First, the frequency-domain exact solutions for the displacements and stresses of the free field are derived in general form for arbitrary incident P and SV waves. With the present formulation, no distinction needs to be made for SV waves with over-critical incident angles that make the reflected P waves disappear, while no critical angle exists for P waves. Next, the equivalent seismic forces of the earthquake (Taft Earthquake 1952) imposed on the near-field boundary are generated by combining the solutions for unit ground accelerations with the earthquake spectrum. Based on the asymmetric finite/infinite element model, the frequency-domain motion equations for seismic analysis are presented with the key parameters selected. The results obtained in frequency and time domain are verified against those of Wolf’s, Luco and de Barros’ and for inversely computed ground motions. The parametric study indicated that distinct phase difference exists between the horizontal and vertical responses for SV waves with over-critical incident angles, but not for under-critical incident angles. Other observations were also made for the numerical results inside the text.

关键词： oblique incident waves     critical angle     half-space     finite/infinite element approach     seismic response analysis    

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Dynamic mechanism for the decline of China’s energy intensity during the 11th FYP (Five-Year Plan)

Minghui LI

《能源前沿（英文）》 2011年 第5卷 第3期   页码 237-249 doi: 10.1007/s11708-010-0130-x

摘要： From 2006 to 2009, the aggregate energy intensity of China fell by 14.38%, which means that China has made substantial progress towards its goal of achieving approximately a 20% reduction in energy intensity during the period of the 11th FYP (Five-Year Plan). This paper describes some new properties of the mechanism for the decrease in China’s energy intensity since the beginning of the 11th FYP. First, compared with the period of the 10th FYP, technical, structural, and residential energy-savings have been improved to a certain extent. Secondly, unlike the dynamic mechanism before 2000, technical energy savings have been the main driver of momentum since the beginning of the 11th FYP. Next, although structural energy savings are not the main factor, they are still a key factor for the decrease in energy intensity. Finally, residential energy savings are still a stable driver of momentum for the decline in China’s energy intensity.

关键词： energy intensity     structural energy savings     technical energy savings    

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Efficiency of scalar and vector intensity measures for seismic slope displacements

Gang WANG

《结构与土木工程前沿（英文）》 2012年 第6卷 第1期   页码 44-52 doi: 10.1007/s11709-012-0138-x

摘要： Ground motion intensity measures are usually used to predict the earthquake-induced displacements in earth dams, soil slopes and soil structures. In this study, the efficiency of various single ground motion intensity measures (scalar ) or a combination of them (vector ) are investigated using the PEER-NGA strong motion database and an equivalent-linear sliding-mass model. Although no single intensity measure is efficient enough for all slope conditions, the spectral acceleration at 1.5 times of the initial slope period and Arias intensity of the input motion are found to be the most efficient scalar for flexible slopes and stiff slopes respectively. Vector can incorporate different characteristics of the ground motion and thus significantly improve the efficiency over a wide range of slope conditions. Among various vector considered, the spectral accelerations at multiple spectral periods achieve high efficiency for a wide range of slope conditions. This study provides useful guidance to the development of more efficient empirical prediction models as well as the ground motion selection criteria for time domain analysis of seismic slope displacements.

关键词： seismic slope displacements     intensity measures     empirical prediction    

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Emergency drinking water treatment in source water pollution incident-technology and practice in China

Xiaojian ZHANG , Chao CHEN ,

《环境科学与工程前沿（英文）》 2009年 第3卷 第3期   页码 364-368 doi: 10.1007/s11783-009-0027-2

摘要： An investigation into emergency potable water treatment technologies was conducted to investigate China’s water pollution situation. In order to confirm optimum parameters, the technological efficiency of each pollutant was obtained. About 100 contaminants were tested to find the emergency treatment technologies, most of which were found to be positive. This paper presents the three largest and most significant water pollution incidents in China to date, analyzing cases such as the nitrobenzene pollution incident in the Songhua River in November 2005, the cadmium pollution incident in the Beijiang River in December 2005, and the water crisis with odorous tap water in Wuxi City in May 2007.

关键词： emergency drinking water treatment     water pollution     adsorption     oxidation     precipitation    

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Does financial development lower energy intensity?

Philip Kofi ADOM, Michael Owusu APPIAH, Mawunyo Prosper AGRADI

《能源前沿（英文）》 2020年 第14卷 第3期   页码 620-634 doi: 10.1007/s11708-019-0619-x

摘要： The growth-induced effects of financial development have been well-established in the empirical literature, as well as the significance of financial development to energy demand behavior. However, the empirical evidence on the relationship between financial development and energy intensity remains sparse in the literature. Given the multifaceted nature of the effects of financial development, the proposed relationship seems a complex one and warrants an empirical investigation. Using the case of Ghana, this study provides an empirical answer to the question: does financial development lower energy intensity? To provide solid grounds for either rejection or acceptance of the null hypothesis, this study performed several robustness checks. Generally, the evidence revealed that financial development lowers energy intensity. Further, the results revealed that the price of energy, trade liberalization and industry structure play significant roles. These results have important implications for the design of macro energy efficiency policies and the creation of a ‘Green Bank’.

关键词： financial development     energy intensity     energy efficiency     Ghana    

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Serum uric acid and risk of incident diabetes in middle-aged and elderly Chinese adults: prospective

Di Cheng, Chunyan Hu, Rui Du, Hongyan Qi, Lin Lin, Xueyan Wu, Lina Ma, Kui Peng, Mian Li, Min Xu, Yu Xu, Yufang Bi, Weiqing Wang, Yuhong Chen, Jieli Lu

《医学前沿（英文）》 2020年 第14卷 第6期   页码 802-810 doi: 10.1007/s11684-019-0723-7

摘要： The association between serum uric acid and the risk of incident diabetes in Chinese adults remains unknown. This study aimed to investigate this association in a community-dwelling population aged≥40 years in Shanghai, China. Oral glucose tolerance test was conducted during baseline and follow-up visits. Relative risk regression was utilized to examine the associations between baseline gender-specific serum uric acid levels and incident diabetes risk. A total of 613 (10.3%) incident diabetes cases were identified during the follow-up visit after 4.5 years. Fasting plasma glucose, postload glucose, and glycated hemoglobin A1c during the follow-up visit progressively increased across the sex-specific quartiles of serum uric acid (all s<0.05). The incidence rate of diabetes increased across the quartiles of serum uric acid (7.43%, 8.77%, 11.47%, and 13.43%). Multivariate adjusted regression analysis revealed that individuals in the highest quartile had 1.36-fold increased risk of diabetes compared with those in the lowest quartile of serum uric acid (odds ratio (95% confidence interval) = 1.36 (1.06−1.73)). Stratified analysis indicated that the association was only observed in women. Accordingly, serum uric acid was associated with the increased risk of incident diabetes among middle-aged and elderly Chinese women.

关键词： incident diabetes     prospective study     uric acid    

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Analysis on carbon emission reduction intensity of fuel cell vehicles from a life-cycle perspective

《能源前沿（英文）》 doi: 10.1007/s11708-023-0909-1

摘要： The hydrogen fuel cell vehicle is rapidly developing in China for carbon reduction and neutrality. This paper evaluated the life-cycle cost and carbon emission of hydrogen energy via lots of field surveys, including hydrogen production and packing in chlor-alkali plants, transport by tube trailers, storage and refueling in hydrogen refueling stations (HRSs), and application for use in two different cities. It also conducted a comparative study for battery electric vehicles (BEVs) and internal combustion engine vehicles (ICEVs). The result indicates that hydrogen fuel cell vehicle (FCV) has the best environmental performance but the highest energy cost. However, a sufficient hydrogen supply can significantly reduce the carbon intensity and FCV energy cost of the current system. The carbon emission for FCV application has the potential to decrease by 73.1% in City A and 43.8% in City B. It only takes 11.0%–20.1% of the BEV emission and 8.2%–9.8% of the ICEV emission. The cost of FCV driving can be reduced by 39.1% in City A. Further improvement can be obtained with an economical and “greener” hydrogen production pathway.

关键词： hydrogen energy     life-cycle assessment (LCA)     fuel cell vehicle     carbon emission     energy cost    

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Low intensity ultrasound stimulates biological activity of aerobic activated sludge

LIU Hong, YAN Yixin, WANG Wenyan, YU Yongyong

《环境科学与工程前沿（英文）》 2007年 第1卷 第1期   页码 67-72 doi: 10.1007/s11783-007-0013-5

摘要： This work aims to explore a procedure to improve biological wastewater treatment efficiency using low intensity ultrasound. The aerobic activated sludge from a municipal wastewater treatment plant was used as the experimental material. Oxygen uptake rate (OUR) of the activated sludge (AS) was determined to indicate the changes of AS activity stimulated by ultrasound at 35 kHz for 0 40 min with ultrasonic intensities of 0 1.2 W/cm. The highest OUR was observed at the ultrasonic intensity of 0.3 W/cm and an irradiation period of 10 min; more than 15% increase was achieved immediately after sonication. More significantly, the AS activity stimulated by ultrasound could last 24 h after sonication, and the AS activity achieved its peak value within 8 h after sonication, or nearly 100% higher than the initial level after sonication. Therefore, to improve the wastewater treatment efficiency of bioreactors, ultrasound with an intensity of 0.3 W/cm could be employed to irradiate a part of the AS in the bioreactor for 10 min every 8 h.

关键词： sonication     irradiation     kHz     treatment efficiency     AS activity    

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强度理论与实验现象

刘大斌,韩文坝,蔡冰清,韩晓东

《中国工程科学》 2007年 第9卷 第12期   页码 44-52

摘要： 用四大经典理论、莫尔强度理论和质点平衡强度理论的准则和强度条件，对单向拉压、二向拉压、纯扭转等已被认定的实验现象进行对比，对低、中碳钢重新做了纯扭转求最大屈服剪应力实验。发现质点平衡强度理论的符合率较高，13个实验中的有12个符合。尤其是拉伸—剪切使剪切破坏试验变得容易，压缩—剪切使剪切破坏试验变得困难的实验现象与质点平衡强度理论完全符合；莫尔强度理论也只有当拉伸和压缩极限强度不同时才能符合；其他强度理论都与此实验不符合。特别是当三向等应力拉伸（或压缩）时第三强度理论出现相当应力为零；三向等应力拉伸（或压

关键词： 强度理论     实验现象     屈服现象     应力状态    

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High-intensity focused ultrasound tumor ablation: Review of ten years of clinical experience

Lian ZHANG, Zhi-Biao WANG

《医学前沿（英文）》 2010年 第4卷 第3期   页码 294-302 doi: 10.1007/s11684-010-0092-8

摘要： High-intensity focused ultrasound (HIFU) is a technique to destroy tissue at depth within the body, selectively and without harming overlying and adjacent structures within the path of the beam because the ultrasonic intensity at the beam focus is much higher than that outside of the focus. Diagnostic ultrasound is the first imaging modality used for guiding HIFU ablation. In 1997, a patient with osteosarcoma was first successfully treated with ultrasound imaging-guided HIFU in Chongqing, China. Over the last decade, thousands of patients with uterine fibroids, liver cancer, breast cancer, pancreatic cancer, bone tumors, and renal cancer have been treated with ultrasound imaging-guided HIFU. Based on several research groups’ reports, as well as our ten-year clinical experience, we conclude that this technique is safe and effective in treating human solid tumors. HIFU is a promising technique. Most importantly, HIFU offers patients another alternative when those patients have no other treatment available.

关键词： high-intensity focused ultrasound (HIFU)     ultrasound imaging-guided HIFU (USgHIFU)     magnetic resonance imaging-guided HIFU (MRgHIFU)    

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标题 作者 时间 类型 操作

A novel light fluctuation spectrum method for in-line particle sizing

Shouxuan QIN, Xiaoshu CAI, Li MA

期刊论文

Fluorene-based narrow-band-gap copolymers for red light-emitting diodes and bulk heterojunction photovoltaic

SUN Mingliang, WANG Li, XIA Yangjun, DU Bin, LIU Ransheng, CAO Yong

期刊论文

On subsurface box-shaped lined tunnel under incident SH-wave propagation

期刊论文

Influence of sprinkler irrigation droplet diameter, application intensity and specific power on flower

Yisheng ZHANG, Delan ZHU

期刊论文

Impact of inter-fuel substitution on energy intensity in Ghana

Boqiang LIN, Hermas ABUDU

期刊论文

Soil seismic analysis for 2D oblique incident waves using exact free-field responses by frequency-based

期刊论文

Dynamic mechanism for the decline of China’s energy intensity during the 11th FYP (Five-Year Plan)

Minghui LI

期刊论文

Efficiency of scalar and vector intensity measures for seismic slope displacements

Gang WANG

期刊论文

Emergency drinking water treatment in source water pollution incident-technology and practice in China

Xiaojian ZHANG , Chao CHEN ,

期刊论文

Does financial development lower energy intensity?

Philip Kofi ADOM, Michael Owusu APPIAH, Mawunyo Prosper AGRADI

期刊论文

Serum uric acid and risk of incident diabetes in middle-aged and elderly Chinese adults: prospective

Di Cheng, Chunyan Hu, Rui Du, Hongyan Qi, Lin Lin, Xueyan Wu, Lina Ma, Kui Peng, Mian Li, Min Xu, Yu Xu, Yufang Bi, Weiqing Wang, Yuhong Chen, Jieli Lu

期刊论文

Analysis on carbon emission reduction intensity of fuel cell vehicles from a life-cycle perspective

期刊论文

Low intensity ultrasound stimulates biological activity of aerobic activated sludge

LIU Hong, YAN Yixin, WANG Wenyan, YU Yongyong

期刊论文

强度理论与实验现象

刘大斌,韩文坝,蔡冰清,韩晓东

期刊论文

High-intensity focused ultrasound tumor ablation: Review of ten years of clinical experience

Lian ZHANG, Zhi-Biao WANG

期刊论文