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期刊论文 19

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DX桩 2

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Defect passivation on cast-mono crystalline screen-printed cells

Alison WENHAM,Lihui SONG,Malcolm ABBOTT,Iskra ZAFIROVSKA,Sisi WANG,Brett HALLAM,Catherine CHAN,Allen BARNETT,Stuart WENHAM

《能源前沿(英文)》 2017年 第11卷 第1期   页码 60-66 doi: 10.1007/s11708-016-0443-5

摘要: Cast-mono crystalline silicon wafers contain crystallographic defects, which can severely impact the electrical performance of solar cells. This paper demonstrates that applying hydrogenation processes at moderate temperatures to finished screen print cells can passivate dislocation clusters within the cast-mono crystalline silicon wafers far better than the hydrogenation received during standard commercial firing conditions. Efficiency enhancements of up to 2% absolute are demonstrated on wafers with high dislocation densities. The impact of illumination to manipulate the charge state of hydrogen during annealing is investigated and found to not be significant on the wafers used in this study. This finding is contrary to a previous study on similar wafers that concluded increased H or H from laser illumination was responsible for the further passivation of positively charged dangling bonds within the dislocation clusters.

关键词: silicon solar cell     dislocation     cast-mono     laser     hydrogen passivation    

Premature melt solidification during mold filling and its influence on the as-cast structure

M. WU, M. AHMADEIN, A. LUDWIG

《机械工程前沿(英文)》 2018年 第13卷 第1期   页码 53-65 doi: 10.1007/s11465-017-0437-y

摘要:

Premature melt solidification is the solidification of a melt during mold filling. In this study, a numerical model is used to analyze the influence of the pouring process on the premature solidification. The numerical model considers three phases, namely, air, melt, and equiaxed crystals. The crystals are assumed to have originated from the heterogeneous nucleation in the undercooled melt resulting from the first contact of the melt with the cold mold during pouring. The transport of the crystals by the melt flow, in accordance with the so-called “big bang” theory, is considered. The crystals are assumed globular in morphology and capable of growing according to the local constitutional undercooling. These crystals can also be remelted by mixing with the superheated melt. As the modeling results, the evolutionary trends of the number density of the crystals and the volume fraction of the solid crystals in the melt during pouring are presented. The calculated number density of the crystals and the volume fraction of the solid crystals in the melt at the end of pouring are used as the initial conditions for the subsequent solidification simulation of the evolution of the as-cast structure. A five-phase volume-average model for mixed columnar-equiaxed solidification is used for the solidification simulation. An improved agreement between the simulation and experimental results is achieved by considering the effect of premature melt solidification during mold filling. Finally, the influences of pouring parameters, namely, pouring temperature, initial mold temperature, and pouring rate, on the premature melt solidification are discussed.

关键词: premature solidification     mold filling     as-cast structure     modeling    

Propagation characteristics of transient waves in low-strain integrity testing on cast-in-situ concrete

Hanlong LIU, Xuanming DING

《结构与土木工程前沿(英文)》 2009年 第3卷 第2期   页码 240-240 doi: 10.1007/s11709-009-0100-8

Micro-sized hydrothermal carbon supporting metal oxide nanoparticles as efficient catalyst for mono-dehydration

Cheng PAN, Chao FAN, Wanqin WANG, Teng LONG, Benhua HUANG, Donghua ZHANG, Peigen SU, Aqun ZHENG, Yang SUN

《能源前沿(英文)》 2022年 第16卷 第5期   页码 822-839 doi: 10.1007/s11708-020-0677-0

摘要: Most known catalytic dehydration of sugar alcohols such as D-sorbitol and D-mannitol can only produce di-dehydrated forms as major product, but mono-dehydrated products are also useful chemicals. Moreover, both di- and mono-dehydration demand a high temperature (150°C or higher), which deserves further attentions. To improve the mono-dehydration efficiency, a series of metal-containing hydrothermal carbonaceous materials (HTC) are prepared as catalyst in this work. Characterization reveals that the composition of preparative solution has a key influence on the morphology of HTC. In transformation of D-sorbitol, all HTC catalysts show low conversions in water regardless of temperature, but much better outputs are obtained in ethanol, especially at a higher temperature. When D-mannitol is selected as substrate, moderate to high conversions are obtained in both water and ethanol. On the other hand, high mono-dehydration selectivity is obtained for both sugar alcohols by using all catalysts. The origin of mono-dehydration selectivity and role of carbon component in catalysis are discussed in association with calculations. This study provides an efficient, mild, eco-friendly, and cost-effective system for mono-dehydration of sugar alcohols, which means a lot to development in new detergents or other fine chemicals.

关键词: hydrothermal carbon     morphology     catalyst     mono-dehydration     sugar alcohol    

Synergistic effects of sodium hypochlorite disinfection and iron-oxidizing bacteria on early corrosion in cast

《环境科学与工程前沿(英文)》 2022年 第16卷 第6期 doi: 10.1007/s11783-021-1506-3

摘要:

• The early corrosion process in the cast iron pipes was investigated.

关键词: Cast iron pipe corrosion     Drinking water distribution systems     Chlorine disinfection     Iron-oxidizing bacteria     Coupling effects    

Influencing mechanism of high solid concentration on anaerobic mono-digestion of sewage sludge without

Yuyao ZHANG,Huan LI,Can LIU,Yingchao CHENG

《环境科学与工程前沿(英文)》 2015年 第9卷 第6期   页码 1108-1116 doi: 10.1007/s11783-015-0806-x

摘要: High-solids anaerobic digestion of sewage sludge was a promising process, but high solid concentration negatively influenced methane production. The influencing mechanism was systematically analyzed in this study through a series of static anaerobic digestion experiments at total solids (TS) contents of 3%–15%. The results showed that TS 6% was the boundary between low-solids and high-solids anaerobic digestion, and the accumulative methane yield decreased exponentially when TS increased from 6% to 15%. The performance of anaerobic digestion was directly determined by the efficiency of mass transfer, and the relation between methane yield and sludge diffusive coefficients was well described by a power function. Thus, the increasing TS resulted in an exponential increase in sludge viscosity but an exponential decrease in diffusive coefficient. The blocked mass transfer led to the accumulation of volatile fatty acids (VFAs) and free ammonia. Acetic metabolism was the main process, whereas butyric and propionic metabolisms occurred at the initial stage of high-solids anaerobic digestion. The concentration of VFAs reached the maximum at the initial stage, which were still lower than the threshold influencing methanogens. The concentration of free ammonia increased gradually, and the methanogenesis was inhibited when free ammonia nitrogen exceeded 50 mg·L . Consequently, the deterioration of high-solids anaerobic digestion was related to the blocked mass transfer and the resulting ammonia accumulation.

关键词: anaerobic digestion     methane     sewage sludge     volatile fatty acids     free ammonia    

Polymerization of methyl methacrylate catalyzed by mono-/bis-salicylaldiminato nickel(II) complexes and

Jihong LU, Danfeng ZHANG, Qian CHEN, Buwei YU

《化学科学与工程前沿(英文)》 2011年 第5卷 第1期   页码 19-25 doi: 10.1007/s11705-010-0546-1

摘要: Two types of salicylaldiminato-based nickel complexes, mono-ligated Ni(II) complexes ([O-C H - - C(H)=N-Ar]Ni(PPh )(Ph) ( ), [O-(3,5-Br )C H - -C(H)=N-Ar]Ni(PPh )(Ph) ( ), [O-(3- -Bu)C H - -C(H)=N-Ar]Ni(PPh )(Ph) ( )) and bis-ligated Ni(II) complexes ([O-(3,5-Br )C H - -C(H)=N-Ar] Ni ( ), [O-(3,5-Br )C H - -C(H)=N-2-C H (PhO)] Ni ( ), Ar=2,6-C H ( -Pr) ) were synthesized and characterized by Fourier transform infrared spectroscopy (FT-IR), nuclear magnetic resonance (NMR), mass spectrography (MS) and elemental analysis (EA). In the presence of methylaluminoxane (MAO) as cocatalyst, all the nickel complexes exhibited high activities for the polymerization of methyl methacrylate (MMA) and syndiotactic-rich poly(methyl methacrylate) (PMMA) was obtained. The complexes with less bulky substituents on salicylaldiminato framework possessed higher activities, while with the same salicylaldiminato, the mono-ligated nickel complexes showed higher catalytic activity than bis-ligated ones.

关键词: late transition metal catalyst     methyl methacrylate     polymerization     salicylaldiminato nickel complexes     methylaluminoxane     syndiotactic structure    

Synthesis of mono and bis-4-methylpiperidiniummethyl-urea as corrosion inhibitors for steel in acidic

Abbas TEIMOURI, Nasrin SOLTANI, Alireza Najafi CHERMAHINI

《化学科学与工程前沿(英文)》 2011年 第5卷 第1期   页码 43-50 doi: 10.1007/s11705-010-0532-7

摘要: Mono and bis-4-methylpiperidiniummethyl urea were synthesized, characterized and used as new corrosion inhibitors of mild steel in the acidic media. Inhibitory effect of two compounds on mild steel surface in the 1 mol·L sulphuric acid has been studied by a series of techniques, such as potentiodynamic polarization, weight loss and quantum chemical calculation methods. Potentiodynamic polarization measurements showed that two inhibitors are mixed type. All measurements showed that inhibition efficiencies enhanced with increase of inhibitor concentration. This reveals that inhibitive actions of inhibitors were mainly due to adsorption on mild steel surface. Density functional (DFT) calculations have been carried out for the title compounds by performing HF and DFT levels of theory using the standard 6-31G* basis set.

关键词: corrosion inhibitors     mild steel     acidic medium     theoretical studies     DFT    

基于可拓学的球墨铸铁石墨形态识别

陈智斌,余永权,杨少敏

《中国工程科学》 2005年 第7卷 第3期   页码 84-89

摘要:

根据石墨的形态特征,运用物元分析方法建立起关于石墨形态识别的物元模型,提出了可拓分类树方法,讨论了可拓分类树的构造和实现途径,并将其应用于石墨形态的类型判别;给出了典型的实验结果,并对该方法与现有识别方法作出比较。

关键词: 物元模型     可拓分类树     石墨形态     球墨铸铁    

nanoflower through protein-inorganic self-assembly, and its application in glycyrrhetinic acid 3-O-mono-β-D-glucuronide

Tian Jiang, Yuhui Hou, Tengjiang Zhang, Xudong Feng, Chun Li

《化学科学与工程前沿(英文)》 2019年 第13卷 第3期   页码 554-562 doi: 10.1007/s11705-019-1834-z

摘要: Glycyrrhetinic acid 3- -mono- -D-glucuronide (GAMG), an important pharmaceutical intermediate and functional sweetener, has broad applications in the food and medical industries. A green and cost-effective method for its preparation is highly desired. Using site-directed mutagenesis, we previously obtained a variant of -glucuronidase from Li-3 (PGUS1), which can specifically transform glycyrrhizin (GL) into GAMG. In this study, a facile method was established to prepare a CaHPO -PGUS1 hybrid nanoflower for enzyme immobilization, based on protein-inorganic hybrid self-assembly. Under optimal conditions, 1.2 mg of a CaHPO -PGUS1 hybrid nanoflower precipitate with 71.2% immobilization efficiency, 35.60 mg∙g loading capacity, and 118% relative activity was obtained. Confocal laser scanning microscope and scanning electron microscope results showed that the enzyme was encapsulated in the CaHPO -PGUS1 hybrid nanoflower. Moreover, the thermostability of the CaHPO -PGUS1 hybrid nanoflower at 55°C was improved, and its half-life increased by 1.3 folds. Additionally, the CaHPO -PGUS1 hybrid nanoflower was used for the preparation of GAMG through GL hydrolysis, with the conversion rate of 92% in 8 h, and after eight consecutive runs, it had 60% of its original activity.

关键词: β-glucuronidase     enzyme-inorganic hybrid nanoflower     biotransformation     glycyrrhizin     glycyrrtinic acid 3-O-mono-β-D-glucuronide    

Influence of surface cracking, anchor head profile, and anchor head size on cast-in headed anchors in

《结构与土木工程前沿(英文)》   页码 1163-1187 doi: 10.1007/s11709-023-0987-5

摘要: In this study, the concrete cone capacity, concrete cone angle, and load–displacement response of cast-in headed anchors in geopolymer concrete are explored using numerical analyses. The concrete damaged plasticity (CDP) model in ABAQUS is used to simulate the behavior of concrete substrates. The tensile behavior of anchors in geopolymer concrete is compared with that in normal concrete as well as that predicted by the linear fracture mechanics (LFM) and concrete capacity design (CCD) models. The results show that the capacity of the anchors in geopolymer concrete is 30%–40% lower than that in normal concrete. The results also indicate that the CCD model overestimates the capacity of the anchors in geopolymer concrete, whereas the LFM model provides a much more conservative prediction. The extent of the difference between the predictions by the numerical analysis and those of the above prediction models depends on the effective embedment depth of the anchor and the anchor head size. The influence of concrete surface cracking on the capacity of the anchor is shown to depend on the location of the crack and the effective embedment depth. The influence of the anchor head profile on the tensile capacity of the anchors is found to be insignificant.

关键词: cast-in anchor     concrete cone capacity     geopolymer concrete     head size     surface crack     anchor profile    

铸钢粗晶的成因及消除方法的研究

邹安全,邓沛然

《中国工程科学》 2005年 第7卷 第4期   页码 79-82

摘要:

通过对ZG32Cr06铸钢粗晶成因的分析及消除粗晶的工艺性能试验,探讨了粗晶导致铸件断裂的机理。试验证明,由于浇铸温度过高,水爆清砂时开箱过早而产生的粗晶可以用热处理方法消除,同时提出了铸件在浇铸时防止粗晶的措施。

关键词: 铸钢     粗晶     水爆清砂     消除方法    

DX桩群桩承载性状的数值分析

张清林,陈立宏

《中国工程科学》 2012年 第14卷 第1期   页码 51-59

摘要:

通过数值计算对不同桩间距的DX桩群桩进行了分析研究。结果表明:DX桩的群桩效应随着桩间距的减小而逐渐明显,间距为6倍桩径的群桩极限承载力是间距为3倍桩径的群桩极限承载力的1.32倍;群桩间距由3倍桩径增大为6倍桩径时,群桩效应系数由0.59增大为0.78;群桩间土体沉降的最大值发生在两扩盘中间位置处,且随着桩间距的增大而减小。

关键词: DX桩     群桩     沉降     数值分析    

DX旋挖挤扩灌注桩单桩抗拔承载性状的数值分析

陈立宏,张清林,袁希雨

《中国工程科学》 2012年 第14卷 第1期   页码 31-36

摘要:

总结了DX桩的抗拔研究现状,采用FLAC3D对具有两个承力盘的DX单桩和相同直径与长度的普通直孔桩做了抗拔的数值计算分析,对DX单桩抗拔的性状进行了研究。模型参数依据土工试验获取并采用现场大比尺试验结果进行校验。通过模拟分级加载,得到了DX桩和直孔桩的抗拔承载力曲线,同时得到了沿桩身的轴力分布,依据这些计算结果展开分析,可以发现DX单桩的抗拔承载力比相同直径的普通直孔桩高出一倍以上,其上下承力盘的发挥作用是由上而下,但当荷载增大到一定程度时,下盘将发挥更大的作用。

关键词: DX桩     抗拔     数值分析    

Control on self-assembly structures of rod-coil-rod (PANI)-(PEG)-(PANI) triblock copolymer

YANG Zhifang, WU Jingao, YANG Yingkui, ZHOU Xingping, XIE Xiaolin

《化学科学与工程前沿(英文)》 2008年 第2卷 第1期   页码 85-88 doi: 10.1007/s11705-008-0003-6

摘要: The self-assembly behaviors of the rod-coil-rod (PANI)-(PEG)-(PANI) triblock copolymer are investigated in different solvents, such as -methyl-2-pyrrolidone (NMP), dimethyl formamide (DMF), ethanol and water. The effects of solvents, concentration and ultrasonic irradiation on self-assembly are discussed. The results indicate that the triblock copolymer forms particles, rods, fiber, networks and fiber bands in the above solvents, respectively. Especially, the triblock copolymer can form a multi-layer, tri-dimensional fibrous network and a petaline structure from the mono-layer fibrous network with the increase of its concentration in ethanol. Also, the ultrasonic irradiation has a great effect on the self-assembly of the triblock copolymer.

关键词: different     multi-layer     mono-layer     dimethyl formamide     concentration    

标题 作者 时间 类型 操作

Defect passivation on cast-mono crystalline screen-printed cells

Alison WENHAM,Lihui SONG,Malcolm ABBOTT,Iskra ZAFIROVSKA,Sisi WANG,Brett HALLAM,Catherine CHAN,Allen BARNETT,Stuart WENHAM

期刊论文

Premature melt solidification during mold filling and its influence on the as-cast structure

M. WU, M. AHMADEIN, A. LUDWIG

期刊论文

Propagation characteristics of transient waves in low-strain integrity testing on cast-in-situ concrete

Hanlong LIU, Xuanming DING

期刊论文

Micro-sized hydrothermal carbon supporting metal oxide nanoparticles as efficient catalyst for mono-dehydration

Cheng PAN, Chao FAN, Wanqin WANG, Teng LONG, Benhua HUANG, Donghua ZHANG, Peigen SU, Aqun ZHENG, Yang SUN

期刊论文

Synergistic effects of sodium hypochlorite disinfection and iron-oxidizing bacteria on early corrosion in cast

期刊论文

Influencing mechanism of high solid concentration on anaerobic mono-digestion of sewage sludge without

Yuyao ZHANG,Huan LI,Can LIU,Yingchao CHENG

期刊论文

Polymerization of methyl methacrylate catalyzed by mono-/bis-salicylaldiminato nickel(II) complexes and

Jihong LU, Danfeng ZHANG, Qian CHEN, Buwei YU

期刊论文

Synthesis of mono and bis-4-methylpiperidiniummethyl-urea as corrosion inhibitors for steel in acidic

Abbas TEIMOURI, Nasrin SOLTANI, Alireza Najafi CHERMAHINI

期刊论文

基于可拓学的球墨铸铁石墨形态识别

陈智斌,余永权,杨少敏

期刊论文

nanoflower through protein-inorganic self-assembly, and its application in glycyrrhetinic acid 3-O-mono-β-D-glucuronide

Tian Jiang, Yuhui Hou, Tengjiang Zhang, Xudong Feng, Chun Li

期刊论文

Influence of surface cracking, anchor head profile, and anchor head size on cast-in headed anchors in

期刊论文

铸钢粗晶的成因及消除方法的研究

邹安全,邓沛然

期刊论文

DX桩群桩承载性状的数值分析

张清林,陈立宏

期刊论文

DX旋挖挤扩灌注桩单桩抗拔承载性状的数值分析

陈立宏,张清林,袁希雨

期刊论文

Control on self-assembly structures of rod-coil-rod (PANI)-(PEG)-(PANI) triblock copolymer

YANG Zhifang, WU Jingao, YANG Yingkui, ZHOU Xingping, XIE Xiaolin

期刊论文