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Multi-effect anthraquinone-based polyimide enclosed SnO/reduced graphene oxide composite as high-performance

《化学科学与工程前沿（英文）》 2023年第17卷第9期页码 1231-1243 doi: 10.1007/s11705-023-2306-z

摘要： The cycling stability of SnO₂ anode as lithium-ion battery is poor due to volume expansion. Polyimide coatings can effectively confine the expansion of SnO₂. However, linear polyimides are easily dissolved in ester electrolytes and their carbonyls is not fully utilized during charging/discharging process. Herein, the SnO₂ enclosed with anthraquinone-based polyimide/reduced graphene oxide composite was prepared by self-assembly. Carbonyls from the anthraquinone unit provide fully available active sites to react with Li⁺, improving the utilization of carbonyl in the polyimide. More exposed carbonyl active sites promote the conversion of Sn to SnO₂ with electrode gradual activation, leading to an increase in reversible capacity during the charge/discharge cycle. In addition, the introduction of reduced graphene oxide cannot only improve the stability of polyimide in the electrolyte, but also build fast ion and electron transport channels for composite electrodes. Due to the multiple effects of anthraquinone-based polyimide and the synergistic effect of reducing graphene oxide, the composite anode exhibits a maximum reversible capacity of 1266 mAh·g⁻¹ at 0.25 A·g⁻¹, and maintains an excellent specific capacity of 983 mAh·g⁻¹ after 200 cycles. This work provides a new strategy for the synergistic modification of SnO₂.

关键词： anthraquinone-based polyimide multi-effect tin dioxide reduced graphene oxide lithium-ion battery

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Advances in the slurry reactor technology of the anthraquinone process for H

Hongbo Li, Bo Zheng, Zhiyong Pan, Baoning Zong, Minghua Qiao

《化学科学与工程前沿（英文）》 2018年第12卷第1期页码 124-131 doi: 10.1007/s11705-017-1676-5

摘要： This paper overviews the development of the anthraquinone auto-oxidation (AO) process for the production of hydrogen peroxide in China and abroad. The characteristics and differences between the fixed-bed and fluidized-bed reactors for the AO process are presented. The detailed comparison indicates that the production of hydrogen peroxide with the fluidized-bed reactor has many advantages, such as lower operation cost and catalyst consumption, less anthraquinone degradation, higher catalyst utilization efficiency, and higher hydrogenation efficiency. The key characters of the production technology of hydrogen peroxide based on the fluidized-bed reactor developed by the Research Institute of Petroleum Processing, Sinopec are also disclosed. It is apparent that substituting the fluidized-bed reactor for the fixed-bed reactor is a major direction of breakthrough for the production technology of hydrogen peroxide in China.

关键词： anthraquinone process fixed-bed reactor slurry-bed reactor hydrogen peroxide

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Preparation and characterization of polyimide/silica/silver composite films

JIANG Lizhong, WU Dezhen, LUO Ning, WU Zhanpeng, MOU Nanxiang

《化学科学与工程前沿（英文）》 2008年第2卷第3期页码 291-295 doi: 10.1007/s11705-008-0059-3

摘要： Polyimide/silica/silver hybrid films were prepared by the sol-gel method combined with single-stage self-metallization technique. The structure of polyimide films in the thermal curing process and the influence of silica content on the migration and aggregation of silver particles to the surface of hybrid films were investigated. The hybrid films were characterized by transmission electron microscopy, dynamic mechanical thermal analysis, Fourier transform infrared spectroscopy, ultraviolet visible spectroscopy and mechanical measurements. The results indicated that there was no degradation of the polyimide matrix after the formation of silica and silver particles. Silica acted as the nucleus for the silver particles. With increasing silica content, more and more silver particles were kept in the hybrid films instead of being migrated onto the surface of the hybrid films and the reflections of hybrid films decreased gradually.

关键词： single-stage self-metallization spectroscopy transmission Polyimide/silica/silver ultraviolet visible

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Dielectric property of polyimide/barium titanate composites and its influence factors (II)

LIU Weidong, ZHU Baoku, XIE Shuhui, XU Zhikang

《化学科学与工程前沿（英文）》 2008年第2卷第4期页码 417-421 doi: 10.1007/s11705-008-0078-0

摘要： Using poly(amic acid) (PAA) as a precursor followed by thermal imidization, the polyimide/barium titanate composite films were successfully prepared by a direct mixing method and in situ process. The influence of processing factors, such as particle size, distribution mode and polymerization method on dielectric properties was studied. Results revealed that the dielectric constant (?) of the composite film increased by using bigger fillers or employing in situ polymerization and bimodal distribution. When the composite film containing 50 Vol-% of BaTiO with size in 100 nm was prepared via in situ process, its dielectric constant reached 45 at 10 kHz.

关键词： thermal imidization dielectric constant particle precursor titanate composite

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Molecular level understanding of CO₂ capture in ionic liquid/polyimide composite membrane

Linlin You, Yandong Guo, Yanjing He, Feng Huo, Shaojuan Zeng, Chunshan Li, Xiangping Zhang, Xiaochun Zhang

《化学科学与工程前沿（英文）》 2022年第16卷第2期页码 141-151 doi: 10.1007/s11705-020-2009-7

摘要： Ionic liquid (IL)/polyimide (PI) composite membranes demonstrate promise for use in CO separation applications. However, few studies have focused on the microscopic mechanism of CO in these composite systems, which is important information for designing new membranes. In this work, a series of systems of CO in 1-butyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide composited with 4,4-(hexafluoroisopropylidene) diphthalic anhydride (6FDA)-based PI, 6FDA-2,3,5,6-tetramethyl-1,4-phenylene-diamine, at different IL concentrations were investigated by all-atom molecular dynamics simulation. The formation of IL regions in PI was found, and the IL regions gradually became continuous channels with increasing IL concentrations. The analysis of the radial distribution functions and hydrogen bond numbers demonstrated that PI had a stronger interaction with cations than anions. However, the hydrogen bonds among PI chains were destroyed by the addition of IL, which was favorable for transporting CO . Furthermore, the self-diffusion coefficient and free energy barrier suggested that the diffusion coefficient of CO decreased with increasing IL concentrations up to 35 wt-% due to the decrease of the fractional free volume of the composite membrane. However, the CO self-diffusion coefficients increased when the IL contents were higher than 35 wt-%, which was attributed to the formation of continuous IL domain that benefitted the transportation of CO .

关键词： carbon dioxide ionic liquid 6FDA-TeMPD composite membrane molecular dynamics simulation

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冷冻-萃取/真空干燥法制备坚固和耐疲劳的聚酰亚胺纤维气凝胶及其增强阻燃性复合材料 Article

姚恺清, 宋崇虎, 方红, 王峰, 陈炼, 蒋少华, 查国君, 侯豪情

《工程（英文）》 2023年第21卷第2期页码 152-161 doi: 10.1016/j.eng.2021.08.024

摘要：

在现代新材料的快速发展中，用节能、省时、低成本和简便的新型方法制备具有优良机械性能和热学性能的轻质、低密度和高孔隙率气凝胶十分必要。在本工作中，我们使用短切电纺聚酰亚胺（PI）纤维作为支撑骨架，通过开发出一种无需特殊干燥方法的真空干燥（VD）与冷冻-萃取相结合的方法，制备出高性能PI 纤维气凝胶（PIFAs）。所得PIFAs 具有低密度（≤52.8 mg⋅cm⁻³）和高孔隙率（>96%）。该PIFA在至少20 000 次的循环压缩过程中展现出高度的耐疲劳性及低能量损失系数。密度为39.1 mg⋅cm⁻³的PIFA具有40.4 mW⋅m⁻¹⋅K⁻¹的热导率。通过进一步使用聚硅氮烷对PIFAs复合改性后，其具备更强的耐火性和氮气氛围中的高残留率（>70%）。这些优异的性能使PIFAs 及其复合材料成为可应用于建筑工业、航空和航天工业轻质材料、隔热和防火层以及高温反应催化剂载体的可选材料。此外，本工作中提出的冷冻-萃取/VD法因其节能、省时和节约成本而可被拓展用于制备其他材料。

关键词：聚酰亚胺气凝胶冷冻萃取真空干燥机械性能隔热性能防火性能

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A comparison of the catalytic hydrogenation of 2-amylanthraquinone and 2-ethylanthraquinone over a Pd/Al

Enxian Yuan, Xiangwei Ren, Li Wang, Wentao Zhao

《化学科学与工程前沿（英文）》 2017年第11卷第2期页码 177-184 doi: 10.1007/s11705-016-1604-0

摘要： The hydrogenation of 2-ethylanthraquinone (eAQ), 2- -amylanthraquinone (taAQ) and their mixtures with molar ratios of 1:1 and 1:2 to the corresponding hydroquinones (eAQH and taAQH ) were studied over a Pd/Al O catalyst in a semi-batch slurry reactor at 60 °C and at 0.3 MPa. Compared to eAQ, TaAQ exhibited a significantly slower hydrogenation rate (about half) but had a higher maximum yield of H O and a smaller amount of degradation products. This can be ascribed to the longer and branched side chain in taAQ, which limits its accessibility to the Pd surface and its diffusion through the pores of the catalyst. Density functional theory calculations showed that it is more difficult for taAQ to adsorb onto a Pd (111) surface than for eAQ. The hydrogenation of the eAQ/taAQ mixtures had the slowest rates, lowest H O yields and the highest amounts of degradation products.

关键词： hydrogenation hydrogen peroxide anthraquinone Pd catalyst AO process

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Triggering the biocontrol of

Kandasamy SARAVANAKUMAR, Zhixiang LU, Hai XIA, Meng WANG, Jianan SUN, Shaoqing WANG, Qiang-qiang WANG, Yaqian LI, Jie CHEN

《农业科学与工程前沿（英文）》 2018年第5卷第2期页码 271-279 doi: 10.15302/J-FASE-2018214

摘要： This study reports a strain of CCTCC-SBW0162 with potential to enhance biocontrol activity against gray mold pathogen, , and with a pivotal role in tomato ( ) plant growth enhancement. A total of 254 isolates were screened by antagonistic assay. Of these, 10 were selected for greenhouse experiments based on their greater inhibition of . The antagonistic assay and greenhouse experiments indicated that CCTCC-SBW0162 gave the highest inhibition rate (90.6%) and disease reduction (80.7%). Also, to study the possible mechanism associated with antifungal activity of CCTCC-SBW0162 against , molecular docking was used to assess the interactions between CCTCC-SBW0162-derived metabolites, and pathogencity and virulence related proteins of . The molecular docking results indicated that the combination of harzianopyridone, harzianolide and anthraquinone C derived from CCTCC-SBW0162 could synergistically improve antifungal activity against through the inhibition/modification of pathogenicity and virulence related proteins. However, this computerized modeling work emphasized the need for further study in the laboratory to confirm the effect derived metabolites against the proteins of and their interactions.

关键词： anthraquinone Botrytis cinerea harzianolide harzianopyridone molecular docking Trichoderma harzianum

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Mamoru Mitsuish：Surgical System of the Future Based on Production Engineering and the Integration of

2021年04月23日

关键词：高性能制造

Autogenous healing mechanism of cement-based materials

《结构与土木工程前沿（英文）》页码 948-963 doi: 10.1007/s11709-023-0960-3

摘要： Autogenous self-healing is the innate and fundamental repair capability of cement-based materials for healing cracks. Many researchers have investigated factors that influence autogenous healing. However, systematic research on the autogenous healing mechanism of cement-based materials is lacking. The healing process mainly involves a chemical process, including further hydration of unhydrated cement and carbonation of calcium oxide and calcium hydroxide. Hence, the autogenous healing process is influenced by the material constituents of the cement composite and the ambient environment. In this study, different factors influencing the healing process of cement-based materials were investigated. Scanning electron microscopy and optical microscopy were used to examine the autogenous healing mechanism, and the maximum healing capacity was assessed. Furthermore, detailed theoretical analysis and quantitative detection of autogenous healing were conducted. This study provides a valuable reference for developing an improved healing technique for cement-based composites.

关键词： autogenous healing cement-based materials healing mechanism aggregation effect

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Urban design based on public safety-Discussion on safety-based urban design

Kaizhen CAI, Jianguo WANG

《结构与土木工程前沿（英文）》 2009年第3卷第2期页码 219-227 doi: 10.1007/s11709-009-0023-4

摘要： Because of public safety problems in construction of urban surroundings, this paper expounds the necessity of the study on public safety-based urban design in perspective of modern city. It brings forward the concept of safety-based urban design and attempts to explore the basic connotation and contents with framework for studies.

关键词： urban public safety urban design safety-based urban design

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Gradient-based compressive image fusion

Yang CHEN,Zheng QIN

《信息与电子工程前沿（英文）》 2015年第16卷第3期页码 227-237 doi: 10.1631/FITEE.1400217

摘要： We present a novel image fusion scheme based on gradient and scrambled block Hadamard ensemble (SBHE) sampling for compressive sensing imaging. First, source images are compressed by compressive sensing, to facilitate the transmission of the sensor. In the fusion phase, the image gradient is calculated to reflect the abundance of its contour information. By compositing the gradient of each image, gradient-based weights are obtained, with which compressive sensing coefficients are achieved. Finally, inverse transformation is applied to the coefficients derived from fusion, and the fused image is obtained. Information entropy (IE), Xydeas’s and Piella’s metrics are applied as non-reference objective metrics to evaluate the fusion quality in line with different fusion schemes. In addition, different image fusion application scenarios are applied to explore the scenario adaptability of the proposed scheme. Simulation results demonstrate that the gradient-based scheme has the best performance, in terms of both subjective judgment and objective metrics. Furthermore, the gradient-based fusion scheme proposed in this paper can be applied in different fusion scenarios.

关键词： Compressive sensing (CS) Image fusion Gradient-based image fusion CS-based image fusion

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Reliability-based design for automobiles in China

ZHANG Yimin

《机械工程前沿（英文）》 2008年第3卷第4期页码 369-374 doi: 10.1007/s11465-008-0064-8

摘要： The level of automobile design and manufacturing is an important sign of leadership in science and technology and economic power. The achievements of theories and methods for reliability-based design of automobiles in China are reviewed. For reliability-based design, the theories and practices, optimization, sensitivity, and robustness are estimated. The techniques of reliability-based design for automobiles are developed. The techniques service to the “hollow” phenomena of kernel technology, product innovative power, and independent development power can be solved.

关键词： reliability-based automobile sensitivity optimization robustness

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Reliability-based robust design optimization of vehicle components, Part I: Theory

Yimin ZHANG

《机械工程前沿（英文）》 2015年第10卷第2期页码 138-144 doi: 10.1007/s11465-015-0333-2

摘要：

The reliability-based design optimization, the reliability sensitivity analysis and robust design method are employed to present a practical and effective approach for reliability-based robust design optimization of vehicle components. A procedure for reliability-based robust design optimization of vehicle components is proposed. Application of the method is illustrated by reliability-based robust design optimization of axle and spring. Numerical results have shown that the proposed method can be trusted to perform reliability-based robust design optimization of vehicle components.

关键词： vehicle components reliability-based design optimization reliability-based sensitivity analysis multi-objective optimization robust design

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Reliability-based robust design optimization of vehicle components, Part II: Case studies

Yimin ZHANG

《机械工程前沿（英文）》 2015年第10卷第2期页码 145-153 doi: 10.1007/s11465-015-0334-1

摘要：

The reliability-based optimization, the reliability-based sensitivity analysis and robust design method are employed to propose an effective approach for reliability-based robust design optimization of vehicle components in Part I. Applications of the method are further discussed for reliability-based robust optimization of vehicle components in this paper. Examples of axles,torsion bar, coil and composite springs are illustrated for numerical investigations. Results have shown the proposed method is an efficient method for reliability-based robust design optimization of vehicle components.

关键词： vehicle axles and springs reliability-based design optimization reliability-based sensitivity analysis multi-objective optimization robust design