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氧化石墨烯 2

聚偏氟乙烯 2

膜制备 2

Al₂O₃-M_xO_y 1

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农业微生物；产业发展；微生物肥料；饲用微生物；微生物农药；酶制剂微生物；微生物种业 1

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Experimental study on compaction-induced anisotropic mechanical property of rockfill material

Xiangtao ZHANG, Yizhao GAO, Yuan WANG, Yu-zhen YU, Xun SUN

《结构与土木工程前沿（英文）》 2021年第15卷第1期页码 109-123 doi: 10.1007/s11709-021-0693-0

摘要： The anisotropy of rockfill materials has a significant influence on the performance of engineering structures. However, relevant research data are very limited, because of the difficulty with preparing specimens with different inclination angles using traditional methods. Furthermore, the anisotropy test of rockfill materials is complex and complicated, especially for triaxial tests, in which the major principal stress plane intersects with the compaction plane at different angles. In this study, the geometric characteristics of a typical particle fraction consisting of a specific rockfill material were statistically investigated, and the distribution characteristics of particle orientation in specimens prepared via different compaction methods were examined. For high-density rockfill materials, a set of specimen preparation devices for inclined compaction planes was developed, and a series of conventional triaxial compression tests with different principal stress direction angles were conducted. The results reveal that the principal stress direction angle has a significant effect on the modulus, shear strength, and dilatancy of the compacted rockfill materials. Analysis of the relationship between the principal stress direction angles, change in the stress state, and change in the corresponding dominant shear plane shows that the angle between the compacted surface and dominant shear plane is closely related to interlocking resistance associated with the particle orientation. In addition, different principal stress direction angles can change the extent of the particle interlocking effect, causing the specimen to exhibit different degrees of anisotropy.

关键词： rockfill inclination of specimen preparation anisotropy mechanical property mechanism

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Effects of inclination angles of disc cutter on machining quality of Nomex honeycomb core in ultrasonic

Yidan WANG, Renke KANG, Yan QIN, Qian MENG, Zhigang DONG

《机械工程前沿（英文）》 2021年第16卷第2期页码 285-297 doi: 10.1007/s11465-021-0631-9

摘要： Ultrasonic cutting with a disc cutter is an advanced machining method for the high-quality processing of Nomex honeycomb core. The machining quality is influenced by ultrasonic cutting parameters, as well as tool orientations, which are determined by the multi-axis machining requirements and the angle control of the cutting system. However, in existing research, the effect of the disc cutter orientation on the machining quality has not been studied in depth, and practical guidance for the use of disc cutters is lacking. In this work, the inclined ultrasonic cutting process with a disc cutter was analyzed, and cutting experiments with different inclination angles were conducted. The theoretical residual height models of the honeycomb core, as a result of the lead and tilt angles, were established and verified with the results obtained by a linear laser displacement sensor. Research shows that the residual height of the honeycomb core, as a result of the tilt angle, is much larger than that as a result of the lead angle. Furthermore, the tearing of the cell wall on the machined surface was observed, and the effects of the ultrasonic vibration, lead angle, and tilt angle on the tear rate and tear length of the cell wall were studied. Experimental results revealed that ultrasonic vibration can effectively decrease the tearing of the cell wall and improve the machining quality. Changes in the tilt angle have less effect than changes in the lead angle on the tearing of the cell wall. The determination of inclination angles should consider the actual processing requirements for the residual height and the machining quality of the cell wall. This study investigates the influence of the inclination angles of a disc cutter on the machining quality of Nomex honeycomb core in ultrasonic cutting and provides guidelines for machining.

关键词： Nomex honeycomb core disc cutter inclined ultrasonic cutting machining quality

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Edge preparation methods for cutting tools: a review

《机械工程前沿（英文）》 2023年第18卷第4期 doi: 10.1007/s11465-023-0766-y

摘要： Edge preparation can remove cutting edge defects, such as burrs, chippings, and grinding marks, generated in the grinding process and improve the cutting performance and service life of tools. Various edge preparation methods have been proposed for different tool matrix materials, geometries, and application requirements. This study presents a scientific and systematic review of the development of tool edge preparation technology and provides ideas for its future development. First, typical edge characterization methods, which associate the microgeometric characteristics of the cutting edge with cutting performance, are briefly introduced. Then, edge preparation methods for cutting tools, in which materials at the cutting edge area are removed to decrease defects and obtain a suitable microgeometry of the cutting edge for machining, are discussed. New edge preparation methods are explored on the basis of existing processing technologies, and the principles, advantages, and limitations of these methods are systematically summarized and analyzed. Edge preparation methods are classified into two categories: mechanical processing methods and nontraditional processing methods. These methods are compared from the aspects of edge consistency, surface quality, efficiency, processing difficulty, machining cost, and general availability. In this manner, a more intuitive understanding of the characteristics can be gained. Finally, the future development direction of tool edge preparation technology is prospected.

关键词： edge preparation method preparation principle cutting edge geometry edge characterization tool performance

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Effects of delamination in drilling glass/polyester composite

Mehdi GANJIANI, Majid SAFARABADI, Nabi MEHRI-KHANSARI, Hossein ORUJI

《结构与土木工程前沿（英文）》 2021年第15卷第2期页码 552-567 doi: 10.1007/s11709-021-0699-7

摘要： Considering failures during machinery processes such as drilling, a precautionary analysis involving delamination and the corresponding dissipated energy is required, especially for composite structures. In this context, because of the complexity of both the analysis procedure and experimental test setup, most studies prefer to represent mode I and III interlaminar crack propagation instead of that involving mode II. Therefore, in this study, the effect of mode delamination and corresponding interlaminar crack propagation was considered during the drilling process of multilayered glass/polyester composites using both numerical and experimental approaches. In the experimental procedure, the mechanical properties of the glass/polyester specimens were obtained according to ASTM D3039. In addition, the interlaminar mixed-mode (I/II) loadings were determined using an ARCAN test fixture so that the fracture toughness of glass/polyester could then be identified. The mode II critical strain energy release rate (CSERR) was then obtained using an experimental test performed using an ARCAN fixture and the virtual crack closure technique (VCCT). It was determined that the numerical approach was in accordance with the experiments, and more than 95% of crack propagation could be attributed to mode II compared to the two other modes.

关键词： delamination VCCT ARCAN specimen drilling mode II

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考虑垫片形状和尺寸效应的珊瑚混凝土劈裂抗拉性能的三维细观研究 Article

吴彰钰, 张锦华, 余红发, 方秦, 麻海燕, 陈力

《工程（英文）》 2022年第17卷第10期页码 110-122 doi: 10.1016/j.eng.2021.02.024

摘要：

珊瑚混凝土（CAC）作为一种新型建筑材料，已经在岛礁工程结构建设领域引起了极大的关注。为了研究CAC的静态劈裂抗拉性能，本文提出了一种考虑骨料形状和空间分布随机性的三维（3D）随机混凝土细观模型，影响因素包括试件形状和支承垫片尺寸。我们建立了12 个不同的混凝土细观模型，按照试件形状可分为两种，即边长为150 mm的立方体和尺寸为ϕ150 mm×300 mm的圆柱体。其中，支承垫片宽度为6 mm、9 mm、12 mm、15 mm、18 mm和20 mm。本文系统分析和讨论了试件几何形状和垫片宽度对CAC劈裂抗拉性能的影响规律，研究内容包括混凝土开裂过程、最终破坏模式和劈裂抗拉强度（f_st）。结果表明：本文所开发的细观模型具有很高的可靠性，并确定了适用于CAC劈裂抗拉性能模拟和预测的最优计算参数。CAC的f_st值与试件形状和垫片宽度直接相关。其中，在垫片尺寸相同的情况下，立方体CAC试件的f_st值要略高于圆柱体模型，表明可以采用断裂面积的差异来解释试件形状效应对CAC f_st值的影响规律。此外，当垫片的相对宽度由0.04 增加到0.13 时，CAC的f_st值会呈现逐渐增大的趋势。基于弹性力学理论，本文初步确定了不同垫片宽度条件下CAC f_st的取值范围，这对于研究CAC的抗拉性能具有重要意义。

关键词：珊瑚混凝土三维细观模拟劈拉试验抗拉强度试件形状支承垫片

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Effect of strata restraint on seismic performance of prefabricated sidewall joints in fabricated subway stations

《结构与土木工程前沿（英文）》 2023年第17卷第5期页码 763-779 doi: 10.1007/s11709-023-0917-6

摘要： A disadvantage of the conventional quasi-static test method is that it does not consider the soil restraint effect. A new method to test the seismic performance of prefabricated specimens for underground assembled structures is proposed, which can realistically reflect the strata restraint effect on the underground structure. Laboratory work combined with finite element (FE) analysis is performed in this study. Three full-scale sidewall specimens with different joint forms are designed and fabricated. Indices related to the seismic performance and damage modes are analyzed comprehensively to reveal the mechanism of the strata restraint effect on the prefabricated sidewall components. Test results show that the strata restraint effect effectively improves the energy dissipation capacity, load-bearing capacity, and the recoverability of the internal deformation of the precast sidewall components. However, the strata restraint effect reduces the ductility of the precast sidewall components and aggravates the shear and bending deformations in the core region of the connection joints. Additionally, the strata restraint effect significantly affects the seismic performance and damage mode of the prefabricated sidewall components. An FE model that can be used to conduct a seismic performance study of prefabricated specimens for underground assembled structures is proposed, and its feasibility is verified via comparison with test data.

关键词： underground structures precast sidewall specimen seismic test method bearing capacity energy dissipation capacity plastic deformation

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The effect of preparation conditions of Pt/Al

Lei YUAN, Xiang ZHENG, Kaijiao DUAN, Hao HU, Jinggang WANG, Seong Ihl WOO, Zhiming LIU

《环境科学与工程前沿（英文）》 2013年第7卷第3期页码 457-463 doi: 10.1007/s11783-013-0512-5

摘要： Selective catalytic reduction of NO by H in the presence of oxygen has been investigated over Pt/Al O catalysts pre-treated under different conditions. Catalyst preparation conditions exert significant influence on the catalytic performance, and the catalyst pre-treated by H or H then followed by O is much more active than that pre-treated by air. The higher surface area and the presence of metallic Pt over Pt/Al O pre-treated by H or pretreated by H then followed by O can contribute to the formation of NO , which then promotes the reaction to proceed at low temperatures.

关键词： NO_x reduction Pt/Al₂O₃ preparation condition H₂-SCR

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Selective preparation for biofuels and high value chemicals based on biochar catalysts

《能源前沿（英文）》 2023年第17卷第5期页码 635-653 doi: 10.1007/s11708-023-0878-4

摘要： The reuse of biomass wastes is crucial toward today’s energy and environmental crisis, among which, biomass-based biochar as catalysts for biofuel and high value chemical production is one of the most clean and economical solutions. In this paper, the recent advances in biofuels and high chemicals for selective production based on biochar catalysts from different biomass wastes are critically summarized. The topics mainly include the modification of biochar catalysts, the preparation of energy products, and the mechanisms of other high-value products. Suitable biochar catalysts can enhance the yield of biofuels and higher-value chemicals. Especially, the feedstock and reaction conditions of biochar catalyst, which affect the efficiency of energy products, have been the focus of recent attentions. Mechanism studies based on biochar catalysts will be helpful to the controlled products. Therefore, the design and advancement of the biochar catalyst based on mechanism research will be beneficial to increase biofuels and the conversion efficiency of chemicals into biomass. The advanced design of biochar catalysts and optimization of operational conditions based on the biomass properties are vital for the selective production of high-value chemicals and biofuels. This paper identifies the latest preparation for energy products and other high-value chemicals based on biochar catalysts progresses and offers insights into improving the yield of high selectivity for products as well as the high recyclability and low toxicity to the environment in future applications.

关键词： biomass biochar catalysts biofuels high chemicals

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A highly efficient methodology for the preparation of

Yongxin Zhang, Shucheng Wang, Yaodong Huang

《化学科学与工程前沿（英文）》 2021年第15卷第3期页码 679-686 doi: 10.1007/s11705-020-1979-9

摘要： A convenient and highly efficient method is described for the synthesis of -methoxycarbazole derivatives, including those with sterically demanding, benzannulated, or strongly electron-donating or -withdrawing substituents. Various -methoxycarbazole derivatives were directly prepared in good-to-moderate yields by the Pd (dba) CHCl /9,9-dimethyl-4,5-bis(diphenylphosphino)xanthene-catalyzed reactions of the corresponding dibromobiphenyl compounds and methoxya-mine. Based on this methodology, the first total synthesis of 3,3′-[oxybis(methylene)]bis(9-methoxy-9 -carbazole), an antimicrobial dimeric carbazole alkaloid previously isolated from the stem bark of , was achieved in 18% yield over seven steps from 1,2-dibromobenzene.

关键词： N-methoxyl carbazole dimeric N-methoxyl carbazole alkaloid total synthesis double N-arylation of methoxyamine

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Kinetics of pozzolanic reaction for preparation of flue gas desulfurizer from fly ash and Ca(OH)2

WANG Jingang, HU Jinbang, WANG Daobin, DUAN Zhenya

《化学科学与工程前沿（英文）》 2007年第1卷第3期页码 266-270 doi: 10.1007/s11705-007-0048-y

摘要： A kinetic model of the pozzolanic reaction for the preparation of flue gas desulfurizers from fly ash and Ca(OH) was deduced on the basis of solid phase reaction kinetic theory. Kinetic expressions and parameters were obtained and verified by experiment. A comparison of calculated results with experimental results showed that precision in kinetic expressions was good. The apparent reaction rate constants of the pozzolanic reaction could be raised by increasing the specific surface area of fly ash and the hydration temperature, and by using a suitable additive.

关键词： comparison calculated pozzolanic reaction precision preparation

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Creep-fatigue crack growth behavior in GH4169 superalloy

Dianyin HU, Xiyuan WANG, Jianxing MAO, Rongqiao WANG

《机械工程前沿（英文）》 2019年第14卷第3期页码 369-376 doi: 10.1007/s11465-018-0489-7

摘要： This study aims to examine the crack growth behavior of turbine disc GH4169 superalloy under creep-fatigue loading. Crack growth experiments were performed on compact tension specimens using trapezoidal waveform with dwell time at the maximum load at 650 °C. The crack growth rate of GH4169 superalloy significantly increased with dwell time. The grain boundaries oxidize during the dwell process, thereby inducing an intergranular creep-fatigue fracture mode. In addition, testing data under the same dwell time showed scattering at the crack growth rate. Consequently, a modified model based on the Saxena equation was proposed by introducing a distribution factor for the crack growth rate. Microstructural observation confirmed that the small grain size and high volume fraction of the d phase led to a fast creep-fatigue crack growth rate at 650 °C, thus indicating that two factors, namely, fine grain and presence of the d phase at the grain boundary, increased the amount of weakened interface at high temperature, in which intergranular cracks may form and propagate.

关键词： crack growth rate creep-fatigue GH4169 superalloy CT specimen dwell time

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preparation of Ag@AgCl/Bio-veins composites and their photocatalytic activity and recyclability

《化学科学与工程前沿（英文）》 2023年第17卷第7期页码 906-917 doi: 10.1007/s11705-022-2273-9

摘要： The industrial application of nano-photocatalysts in wastewater treatment has been severely restricted for a long time due to their difficult separation, poor reusability, and low efficiency. In this work, a facile strategy was proposed to enhance the photocatalytic activity and recovery performance of Ag@AgCl nanocatalysts. Biological veins (Bio-veins) with a unique 3D porous construction were used as carriers for the in-situ growth of Ag@AgCl nanoparticles. Scanning electron microscopy results showed that the Ag@AgCl nanoparticles were uniformly loaded on the surface and interior of the Bio-veins, and the size of the Ag@AgCl nanoparticles immobilized on the Bio-veins (50–300 nm) was significantly smaller than Ag@AgCl obtained by the co-precipitation method (1–3 μm). The Bio-veins played a vital role in the photocatalysis reaction system. The degradation efficiency of the Ag@AgCl/Bio-veins(CI4) was up to 3.50 times as high as pure Ag@AgCl. Furthermore, the composites also exhibited excellent recyclability and stability under both visible and solar light. This work provided a suitable strategy for nano-photocatalysts for practical application and may also offer new possibilities for the high-value utilization of biomass materials.

关键词： Ag@AgCl biological veins photocatalytic activity recyclability

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Effect of preparation parameters on catalytic properties of Pt/graphite

LIU Zhengqian, MA Jun, ZHAO Lei

《环境科学与工程前沿（英文）》 2007年第1卷第4期页码 482-487 doi: 10.1007/s11783-007-0077-2

摘要： Catalytic ozonation of aqueous solutions of oxalic acid was examined in the presence of graphite-supported platinum catalysts. The catalytic activity of graphite was significantly enhanced by loading platinum. The removal efficiency of oxalic acid was 3.0%, 47.6% and 99.3% for ozonation alone, graphite catalytic ozonation and Pt/graphite catalytic ozonation in 30 min under the experimental condition, respectively. The influence of support pretreatment, solvent, impregnation time, platinum loading amount and reduction temperature on the activity of Pt/graphite catalyst was investigated. The pretreatment of graphite support had no effect on activity improvement of Pt/graphite catalyst. Solvent and impregnation time also had no great effect on the activity. Platinum loading amount and reduction temperature influenced the catalyst activity significantly. The optimal catalytic performance of Pt/graphite was obtained when 1.0% platinum loading and 623 K of reduction temperature was adopted. The Pt/graphite catalyst was used for five times with no significant decrease in its activity and more than 90% oxalic acid removal was obtained.

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Preparation and application of magnetic microsphere carriers

ZHANG Bo, XING Jianmin, LIU Huizhou

《化学科学与工程前沿（英文）》 2007年第1卷第1期页码 96-101 doi: 10.1007/s11705-007-0019-3

摘要： Magnetic microsphere carriers have received considerable attention, primarily because of their wide applications in the fields of biomedicine and bioengineering. In this paper, preparation methods, surface modification and application of magnetic carriers are reviewed. Emphasis will be placed on recent biological and biomedical developments and trends such as enzyme immobilization, cell isolation, protein purification, target drugs and DNA separation.

关键词： microsphere biomedicine DNA purification preparation

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Reactive extraction for preparation of hydrogen peroxide under pressure

CHENG Yongxi, LI Hongtao, WANG Li, LÜ Shuxiang

《化学科学与工程前沿（英文）》 2008年第2卷第3期页码 335-340 doi: 10.1007/s11705-008-0042-z

摘要： The preparation of hydrogen peroxide from anthrahydroquinone by reactive extraction was investigated. The integration process of oxidation of anthrahydroquinone by air and extraction of hydrogen peroxide from the organic phase with water was carried out in a sieve plate column under pressure. The conversion of anthrahydroquinone increased with increasing pressure resulting in an increase of hydrogen peroxide concentration in the aqueous phase. However, no change in extraction efficiency of hydrogen peroxide was observed. A mathematical model for gas-liquid-liquid reactive extraction was established. In the model, the effects of pressure and gas superficial velocity on reaction were considered. With increasing gas superficial velocity, the conversion of anthrahydroquinone increased, and the fraction of hydrogen peroxide extracted reached a plateau with a maximum of 72.94%. However, both the conversion of anthrahydroquinone and the fraction of hydrogen peroxide extracted decreased with increasing organic phase superficial velocity.

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标题作者时间类型操作

Experimental study on compaction-induced anisotropic mechanical property of rockfill material

Xiangtao ZHANG, Yizhao GAO, Yuan WANG, Yu-zhen YU, Xun SUN

期刊论文

Effects of inclination angles of disc cutter on machining quality of Nomex honeycomb core in ultrasonic

Yidan WANG, Renke KANG, Yan QIN, Qian MENG, Zhigang DONG

期刊论文

Edge preparation methods for cutting tools: a review

期刊论文

Effects of delamination in drilling glass/polyester composite

Mehdi GANJIANI, Majid SAFARABADI, Nabi MEHRI-KHANSARI, Hossein ORUJI