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Porous silica synthesis out of coal fly ash with no residue generation and complete silicon separation

《环境科学与工程前沿（英文）》 2023年第17卷第9期 doi: 10.1007/s11783-023-1712-2

摘要：

● Both amorphous and crystalline silicon are completely separated from coal fly ash.

关键词： Coal fly ash Alkali fusion Micro-/meso-porous Si Zeolite MCM-48 Crystalline transformation

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Crystalline porous materials: from zeolites to metal-organic frameworks (MOFs)

Zaiku Xie, Bao-Lian Su

《化学科学与工程前沿（英文）》 2020年第14卷第2期页码 123-126 doi: 10.1007/s11705-020-1921-1

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Transition metal doped mesoporous titania with a crystalline framework as catalysts for oxidation of

YANG Zehui, OU Encai, WANG Yunan, PENG Li, WANG Jiaqiang, YIN Lihui

《化学科学与工程前沿（英文）》 2008年第2卷第3期页码 296-300 doi: 10.1007/s11705-008-0044-x

摘要： Transition metal M (M = Mn, Fe, Co, Ni, Cu, and Zn) doped mesoporous titania with a crystalline framework was employed as catalysts for the oxidation of -bromotoluene (PBT) to -bromobenzaldehyde (BBD) in acetic acid using aqueous hydrogen peroxide as oxidant. It was found that mesoporous TiO doped with those metals (Fe, Co and Ni) whose atomic radii are relatively smaller exhibited higher conversion rate of PBT. Among these catalysts, the Co/meso-TiO exhibited high substrate conversion and good product (-bromobenzaldehyde) selectivity plus it can be reused once with almost the same activity. The effect of different Ti/Co (molar) ratio on the activities of Co/meso-TiO was also investigated.

关键词： selectivity conversion -bromobenzaldehyde aqueous hydrogen oxidation

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Hydrothermal synthesis of crystalline α-/β-MnO2 nanorods via γ-MnOOH nanorod precursors

ZHANG Weixin, REN Xiangbin, YANG Zeheng, WANG Hua, WANG Qiang, HUANG Fei

《化学科学与工程前沿（英文）》 2007年第1卷第4期页码 365-371 doi: 10.1007/s11705-007-0066-9

摘要： The crystalline -MnO and -MnO nanorods have been successfully prepared via a facile hydrothermal method from -MnOOH nanorods precursor, respectively. The samples were characterized by means of X-ray diff raction (XRD), transmission electron microscopy (TEM), high-resolution transmission electron microscopy (HRTEM), field emission scanning electron microscope (FESEM) and Fourier transformed infrared spectra (FTIR). The morphology and structure of -MnOOH nanorods precursors have a great influence on the crystal structure of the obtained products. The -MnO nanorods are prepared from the 100°C -MnOOH precursor, while the -MnO nanorods are obtained from the 150°C -MnOOH precursor, respectively. Besides, the catalytic activity of the prepared -MnO and -MnO nanorods for the HO decomposition has been investigated comparatively, and the latter shows better catalytic activity.

关键词： obtained -MnOOH precursor Besides high-resolution transmission precursor

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Impact of thermal processes on multi-crystalline silicon

Moonyong KIM,Phillip HAMER,Hongzhao LI,David PAYNE,Stuart WENHAM,Malcolm ABBOTT,Brett HALLAM

《能源前沿（英文）》 2017年第11卷第1期页码 32-41 doi: 10.1007/s11708-016-0427-5

摘要： Fabrication of modern multi-crystalline silicon solar cells involves multiple processes that are thermally intensive. These include emitter diffusion, thermal oxidation and firing of the metal contacts. This paper illustrates the variation and potential effects upon recombination in the wafers due to these thermal processes. The use of light emitter diffusions more compatible with selective emitter designs had a more detrimental effect on the bulk lifetime of the silicon than that of heavier diffusions compatible with a homogenous emitter design and screen-printed contacts. This was primarily due to a reduced effectiveness of gettering for the light emitter. This reduction in lifetime could be mitigated through the use of a dedicated gettering process applied before emitter diffusion. Thermal oxidations could greatly improve surface passivation in the intra-grain regions, with the higher temperatures yielding the highest quality surface passivation. However, the higher temperatures also led to an increase in bulk recombination either due to a reduced effectiveness of gettering, or due to the presence of a thicker oxide layer, which may interrupt hydrogen passivation. The effects of fast firing were separated into thermal effects and hydrogenation effects. While hydrogen can passivate defects hence improving the performance, thermal effects during fast firing can dissolve precipitating impurities such as iron or de-getter impurities hence lower the performance, leading to a poisoning of the intra-grain regions.

关键词： gettering grain boundaries hydrogen impurities oxidation passivation solar cell

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Influence of crystalline phase of Li-Al-O oxides on the activity of Wacker-type catalysts in dimethyl

Yadong GE, Yuanyuan DONG, Shengping WANG, Yujun ZHAO, Jing LV, Xinbin MA

《化学科学与工程前沿（英文）》 2012年第6卷第4期页码 415-422 doi: 10.1007/s11705-012-1214-4

摘要： The catalysts supported on LiAl O (spinel) for vapor phase synthesis of dimethyl carbonate (DMC) from methyl nitrite (MN) have been studied. Their catalytic activities on supports prepared by different methods were evaluated in a continuous reactor. The samples were characterized by powder X-ray diffraction, N adsorption-desorption isotherms, fourier transform infrared spectroscopy and temperature-programmed reduction of H . Li/Al molar ratio and calcination temperature greatly influence the structure of crystalline phase of Li-Al-O oxides. Desirable LiAl O (spinel) was formed at 800°C, while LiAl O (primitive cube) formed at 900°C is undesirable for the reaction. A high Li/Al molar ratio, which was related with LiAlO , also slowed the reaction rate. The electron transfer ability and the interaction with active component are the important properties of the spinel-based supports. The CuCl -PdCl /LiAl O (spinel) with better electron transfer ability and low Pd reduction temperature exhibited a better catalytic ability.

关键词： Wacker-type catalyst dimethyl carbonate methyl nitrite spinel

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An industrial solution to light-induced degradation of crystalline silicon solar cells

Meng XIE,Changrui REN,Liming FU,Xiaodong QIU,Xuegong YU,Deren YANG

《能源前沿（英文）》 2017年第11卷第1期页码 67-71 doi: 10.1007/s11708-016-0430-x

摘要： Boron-oxygen defects can cause serious light-induced degradation (LID) of commercial solar cells based on the boron-doped crystalline silicon (c-Si), which are formed under the injection of excess carriers induced either by illumination or applying forward bias. In this contribution, we have demonstrated that the passivation process of boron-oxygen defects can be induced by applying forward bias for a large quantity of solar cells, which is much more economic than light illumination. We have used this strategy to trigger the passivation process of batches of aluminum back surface field (Al-BSF) solar cells and passivated emitter and rear contact (PERC) solar cells. Both kinds of the treated solar cells show high stability in efficiency and suffer from very little LID under further illumination at room temperature. This technology is of significance for the suppression of LID of c-Si solar cells for the industrial manufacture.

关键词： Boron-oxygen defects c-Si solar cells light-induced degradation passivation forward bias

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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

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Transformation of triclosan by a novel cold-adapted laccase from

Yuanyuan Shi, Deyang Kong, Jiayang Liu, Junhe Lu, Xiaoming Yin, Quansuo Zhou

《环境科学与工程前沿（英文）》 2017年第11卷第3期 doi: 10.1007/s11783-017-0927-5

摘要： This work investigated the transformation of triclosan (TCS) by laccase produced by a pathogen isolated from rotten tomato. The pathogen was characterized as sp. FQ, belonging to subphylum . The laccase exhibited cold-adaptation with relatively high activity at 20°C. The laccase could effectively transform TCS. Approximately 62% TCS could be removed at dose of 1.0 unit·mL in 120 min. The reaction rate appeared to be to the concentration of the substrate, suggesting the laccase activity remained stable during the reaction. Transformation products of TCS were analyzed by mass spectrometry and it was revealed that TCS dimers were formed via radical coupling pathways. During this process, laccase catalyzed oxidation of TCS to form a radical intermediate is the rate limiting step. However, this step can be reversed by humic acid. Overall, the laccase showed great potential in the treatment of phenolic contaminants. Since laccase is widely presented in natural environment, this study also revealed an important pathway involved in the transformation of phenolic contaminants in the environment.

关键词： Laccase Botrytis cinerea Triclosan Transformation Kinetics

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FOOD SYSTEMS TRANSFORMATION: CONCEPTS, MECHANISMS AND PRACTICES

《农业科学与工程前沿（英文）》 2023年第10卷第1期页码 1-3 doi: 10.15302/J-FASE-2023491

摘要： FOOD SYSTEMS TRANSFORMATION: CONCEPTS, MECHANISMS AND PRACTICES

关键词： TRANSFORMATION SYSTEMS FOOD CONCEPTS MECHANISMS

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TRANSFORMATION OF FOOD SYSTEMS: HOW CAN IT BE FINANCED?

《农业科学与工程前沿（英文）》 2023年第10卷第1期页码 109-123 doi: 10.15302/J-FASE-2023483

摘要：

● The analysis of financing for the transformation of food systems requires first a consideration of costs.

关键词： financial markets food systems development financing consumer expenditures public budgets Sustainable Development Goals

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The transformation of PAHs in the sewage sludge incineration treatment

Hui ZHANG,Le XU,Yifei ZHANG,Mengchan JIANG

《环境科学与工程前沿（英文）》 2016年第10卷第2期页码 336-340 doi: 10.1007/s11783-014-0766-6

摘要： The release of pollutants from sewage sludge in the treatment process is a worldwide tricky problem in the field of sludge treatment. In this paper, the release and reaction between monomers of polycyclic aromatic hydrocarbons (PAHs) in the sewage sludge incineration treatment were studied based on simulated experiments. The result indicates that the transformation may occurre between monomers of PAHs during their release in the treatment. Over 90% of total PAHs in sewage sludge are released at the the temperature of 300°C–750°C. The possible transformation of Naphthalene to indeno(1, 2, 3-cd)pyrene was related to the temperature of the treatment system. Here, we showed that the output rate of transformation reactions for indeno(1, 2, 3-cd)pyrene is 94% at 300°C. These findings, by identifying corresponding treatment conditions as well as techniques, can help to understand the reactions and control real outputs of PAHs in the treatment process.

关键词： release of monomers transformation of monomers PAHs sewage sludge incineration treatment

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面向数字化转型的“互联网 +”战略升级研究

何伟,张伟东,王超贤

《中国工程科学》 2020年第22卷第4期页码 10-17 doi: 10.15302/J-SSCAE-2020.04.002

摘要：

“互联网 +”行动计划推出5年来，新一代信息技术创新进一步加快，经济社会数字化转型呈现诸多新特征，这就要求深入研究构建转型新体系和探索转型新路径，谋划“互联网 +”行动举措演进升级。本文遵循技术产业变革的客观规律，基于技术经济理论范式，着重分析了当前技术、应用和政策等层面数字化转型新态势和转型前沿实践探索。研究表明，当前数字化转型技术体系和技术能力日益完善，新的转型目标蓝图逐步显现，信息技术和实体经济融合进入新阶段，面临着重构数字化转型框架体系，强化转型关键要素、突破转型关键环节的重要任务。对此建议，在“互联网 +”行动后续政策设计、国家“十四五”规划制定的过程中，发掘数字化要素潜力，推动数字化转型生态建设，构建转型创新网络，升级“互联网 +”政策保障体系，推动经济社会数字化转型迈向更高发展水平。

关键词：技术产业变革数字化转型互联网+ 产业升级

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Crystal-to-crystal transformation from the triclinic to the cubic crystal system by partial desolvation

Qianqian Guo, Irmgard Kalf, Ulli Englert

《化学科学与工程前沿（英文）》 2018年第12卷第3期页码 433-439 doi: 10.1007/s11705-018-1743-6

摘要：

Diffusion reaction of the labile building block Mg(acacCN)₂ (acacCN= 3-cyanoacetylacetonate) with silver salts leads to a series of solvated Mg/Ag bimetallic coordination polymers with composition [Mg(acacCN)₃Ag]·solvent. Despite their common stoichiometry, the topology of these polymers depends on the solvent of crystallization. The two-dimensional coordination compound [Mg(acacCN)₃Ag]·4CHCl₃ in space group P $\overset{&OverBar;}{1}$ is obtained as platelet-shaped crystals from a mixture of methanol and chloroform. When kept in the reaction mixture, these thin plates within one week convert to isometric tetrahedral crystals of the 3D network [Mg(acacCN)₃Ag]·2CHCl₃ in the cubic space group P2₁3. The transformation reaction proceeds via dissolution and recrystallization. The co-crystallized solvent molecules play an important role for stabilizing the target structure: They subtend Cl···Cl contacts and interact via non-classical C–H···O hydrogen bonds with the coordination framework. In the new cubic coordination network, both Mg(II) and Ag(I) adopt octahedral coordination, with unprecedented face-sharing by bridging O atoms of three acetylacetonato moieties. Prolonged standing of [Mg(acacCN)₃Ag]·2CHCl₃ in the reaction medium leads to further degradation, under formation of [Ag(acacCN)].

关键词： ditopic ligand substituted acetylacetone desolvation diffraction

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Polymorphism and crystal transformation of penicillin sulfoxide

Dingding JING, Yongli WANG, Zhijian CHEN, Lina ZHOU, Jingkang WANG

《化学科学与工程前沿（英文）》 2011年第5卷第4期页码 442-447 doi: 10.1007/s11705-011-1140-x

摘要： Penicillin sulfoxide is the intermediate for the synthesis of 7-amino-3-desacetoxycephalosporanic acid which is one of the most important nucleuses of cephalosporin antibiotic. In this contribution, two crystal structures of penicillin sulfoxide (forms I and II) were determined by X-ray diffraction, and their thermotropic properties were investigated by differential scanning calorimetry (DSC). Furthermore, the transformation of form II to form I was studied quantitatively by Raman spectroscopy, and its rates at different temperatures were determined. The results indicate that penicillin sulfoxide is more stable as form I, and the temperature plays an important role in the crystal transformation.

关键词： penicillin sulfoxide crystallization polymorphism crystal transformation Raman spectroscopy