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disrupting chemicals from water through urethane functionalization of microfiltration membranes via electronbeam irradiation

《环境科学与工程前沿（英文）》 2023年第18卷第4期 doi: 10.1007/s11783-024-1805-6

摘要：

● Urethane functionalities created on PES membranes via electron beam irradiation.

关键词： Surface functionalization Electron beam irradiation Microfiltration Endocrine disrupting chemicals

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Effects on mechanical properties in electron beam welding of TC4 alloy by laser shock processing

LU Jinzhong, ZHANG Yongkang, KONG Dejun, REN Xudong, GE Tao, ZOU Shikun

《机械工程前沿（英文）》 2007年第2卷第4期页码 478-482 doi: 10.1007/s11465-007-0083-x

摘要： The surface of TC4 titanium alloy welding line by electron beam welding (EBW) was processed by high power Q-switched and repetition-rate Nd: glass laser. Effects of laser power and spot diameter on residual stress and micro-hardness of the TC4 alloy welding line by laser shock processing (LSP) have been analyzed. Results show that residual stresses almost do not change as laser power is 45.9 J, spot diameter is φ9 mm; While laser power is 45.9 J, spot diameter less than φ3 mm, the distribution of residual stress in welding line occurs obvious variation, which residual stress increase obviously with spot diameter decrease. When power density is bigger than 1.8×10 W/cm, residual stresses of electron beam welding line occur change by LSP, which improve obviously residual stress distribution; while laser power is bigger than 1.2×10 W/cm, the surface micro-hardness of electron beam welding line occurs change by LSP, which improve obviously micro-hardness distribution. Mechanical properties of TC4 titanium alloy welding line will be improved by LSP, which provides experimental foundation for further controlling the distributions of residual stress and micro-hardness during laser shock processing.

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Kinetics and mechanisms of reactions for hydrated electron with chlorinated benzenes in aqueous solution

Haixia YUAN,Huxiang PAN,Jin SHI,Hongjing LI,Wenbo DONG

《环境科学与工程前沿（英文）》 2015年第9卷第4期页码 583-590 doi: 10.1007/s11783-014-0691-8

摘要： The reactions between chlorinated benzenes (CBzs) and hydrated electron ( ) were investigated by the electron beam (EB) and laser flash photolysis (LFP) experiments. Under the EB irradiation, the effects of irradiation dose, initial concentration and the number of Cl atoms on the removal efficiencies were further examined. At 10 kGy, the removal efficiencies of mono-CB, 1,3-diCB, 1,2-diCB and 1,4-diCB were 41.2%, 87.2%, 84.0%, and 84.1%, respectively. While irradiation dose was 50 kGy, the removal efficiencies increased to 47.4%, 95.8%, 95.0%, and 95.2%, respectively. Irradiation of CBzs solutions has shown that the higher the initial concentration, the lower the percentage of CBzs removal. In addition to this, the dechlorination efficiencies of 1,2-dichlorobenzene (1,2-diCB), 1,3-dichlorobenzene (1,3-diCB) and 1,4-dichlorobenzene (1,4-diCB) were much higher than that of chlorobenzene (mono-CB). The kinetics of the reactions was achieved with nanosecond LFP. The rate constants of second-order reaction between with mono-CB, 1,2-diCB, 1,3-diCB and 1,4-diCB were (5.3±0.4) × 10 , (4.76±0.1) × 10 , (1.01±0.1) × 10 and (3.29±0.2) × 10 L·mol ·s , respectively. Density functional theory (DFT) calculations were performed to determine the optical properties of unstable CBzs anion radicals, and the main absorption peaks lied in the range of 300–550 nm. The primary reaction pathway of CBzs with was gradual dechlorination, and the major products were Cl and benzene (CBzs(-Cl )). Furthermore, biphenyl (or chlorobiphenyl) was observed during the LFP, which was probably formed by recombination of benzene radicals.

关键词： chlorinated benzenes hydrated electron electron beam laser flash photolysis

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用于介观模拟电子束选区熔化的数据挖掘技术 Article

钱亚, 闫文韬, 林峰

《工程（英文）》 2019年第5卷第4期页码 746-754 doi: 10.1016/j.eng.2019.06.006

摘要：

在电子束选区熔化技术（EBSM）工艺中，制造部件的性质受到每一道熔道沉积质量的影响。然而，熔道的形成受到各种物理现象和工艺参数的支配，这些参数之间的相关性十分复杂，难以通过实验得出。近来，介观建模技术已成为模拟电子束（EB）熔化过程以及揭示特定熔道形貌的形成机制的手段。尽管如此，人们对工艺参数与熔道特征之间的相关性尚未有定量的理解。本文从介观模拟的结果出发，研究了熔道的形态特征，同时引入了熔道宽度和高度等关键性描述指标，以便从数值上评估沉积质量。本文还定量研究了各种工艺参数的影响，从而导出了工艺条件和熔道特征之间的相关性。最后，本文提出了一种由介观建模和数据挖掘技术组成的仿真驱动优化框架，并讨论了框架的潜力和局限性。

关键词：电子束选区熔化介观模型数据挖掘

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纳米测量仪器和纳米加工技术

姚骏恩

《中国工程科学》 2003年第5卷第1期页码 33-37

摘要：

纳米科技是当今国际上的一个热点。文章对纳米科技作了简要介绍, 纳米测量和加工是纳米科技中的一个不可缺少的重要组成部分。叙述了发展纳米测量和纳米加工技术的两个主要途径：一是发展传统技术，主要是电子显微术以及最近发展起来的聚焦离子束（FIB）- 电子束数控加工中心；二是创造新的测量仪器，建立新原理和新方法，介绍了国内外电子显微镜和扫描探针显微镜这两类纳米测量分析仪器的发展、应用和生产现状。指出我国电子显微仪器和扫描探针显微镜的开发和生产面临困境，应尽快建立和加强自己的电子显微仪器和扫描探针显微镜等纳米测量和纳米加工设备制造产业，并列入国家科技发展规划。

关键词：纳米科技纳米测量电子显微镜扫描探针显微镜聚焦离子束-电子束装置仪器生产

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电子束选区熔化过程的建模研究及实验验证

闫文韬, 钱亚, 马维馨, 周斌, 沈泳星, 林峰

《工程（英文）》 2017年第3卷第5期页码 701-707 doi: 10.1016/J.ENG.2017.05.021

摘要：

电子束选区熔化技术（EBSM）是一种很有潜力的增材制造（AM）技术。EBSM 由三个主要步骤组成：铺设粉层、预热至粉末略烧结和选区熔化粉末床。这些步骤中涉及高度瞬态多物理场现象，给原位实验的观察和测量带来了重大挑战。利用了高保真模型和后处理实验，来增强对各个步骤中物理机制的理解。模型模拟了实际制造过程，包括：使用离散元法（DEM）的铺粉模型、粉末烧结（固态烧结）的相场（PF）模型和使用有限体积法（FVM）的粉末熔化（液态烧结）模型。本文对所有主要步骤进行了全面的分析，这些分析很少有人报道过。初步模拟结果（包括粉末颗粒在粉末床内的堆积、颗粒之间烧结颈的形成和单道成形缺陷）与实验结果基本一致，表明该模型可以诠释所述机制，并能够指导实验设置和制造过程的设计和优化。

关键词：建模电子束增材制造粉末尺度

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双金属电子束选区熔化的硬件开发与成形实验 Article

郭超, 葛文君, 林峰

《工程（英文）》 2015年第1卷第1期页码 124-130 doi: 10.15302/J-ENG-2015013

摘要：

电子束选区熔化（EBSM）是一种利用电子束扫描、熔化金属粉末逐层制造三维实体零件的增材制造技术。近年来，EBSM已经成功应用于多种材料的增材制造。现有EBSM工艺方面的研究主要聚焦于单种材料的成形，本研究提出一种能够利用两种粉末材料成形梯度结构的EBSM工艺，提出基于振动的粉末供给方法，并实现了两种粉末材料独立供给并混合。利用Ti6Al4V和Ti47Al2Cr2Nb两种材料进行成形。Ti6Al4V在室温下有很好的强度与塑性，而Ti47Al2Cr2Nb在高温下性能优良，但有很大的室温脆性。本研究提出的双金属EBSM工艺成功制备了Ti6Al4V/Ti47Al2Cr2Nb梯度结构，并利用光学显微镜、扫描电子显微镜、电子微探针分析等方法研究了该梯度结构的微观组织和化学成分。结果显示，梯度结构的截面厚度约为300 μm，没有裂纹，化学成分在界面处呈阶梯式变化。

关键词：增材制造电子束选区熔化梯度材料钛合金钛铝合金

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Erratum to ‘‘Modeling and Experimental Validation of the Electron Beam Selective Melting Erratum

Wentao Yan, Ya Qian, Weixin Ma, Bin Zhou, Yongxing Shen, Feng Lin

《工程（英文）》 2018年第4卷第1期页码 164-164 doi: 10.1016/j.eng.2017.12.012

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激光相变热处理对TC４电子束焊缝残余应力的影响

鲁金忠,张永康,孔德军,任旭东,邹世坤,王西昌

《中国工程科学》 2007年第9卷第5期页码 72-76

摘要：

利用CO₂激光相变热处理技术对TC4钛合金电子束焊缝进行了处理，研究了激光功率、光斑直径、辅助气体等激光工艺参数对电子束焊缝残余应力分布的影响。实验结果表明，激光相变热处理改善了焊缝残余应力的分布，使焊缝表面残余应力由拉应力转变为压应力，其压应力值随着激光功率的增加而增大，随着激光光斑直径的减小而增加；辅助气体为O₂时残余压应力值比辅助气体为N₂大30～40MPa，激光相变热处理显著提高了TC4钛合金电子束焊缝的残余压应力及其使用寿命。

关键词：激光相变热处理 TC4钛合金电子束焊缝残余应力

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Decomposition of aqueous chlorinated contaminants by UV irradiation with H

Eunsung KAN,Chang-Il KOH,Kyunghyuk LEE,Joonwun KANG

《环境科学与工程前沿（英文）》 2015年第9卷第3期页码 429-435 doi: 10.1007/s11783-014-0677-6

摘要： In the present study, the decomposition rates of carbon tetrachloride (CCl ) and 2,4-dichlorophenol (2,4-DCP) in water by the ultraviolet (UV) light irradiation alone and H O /UV were experimentally investigated. The detailed experimental studies have been conducted for examining treatment capacities of the two different ultraviolet light sources (low and medium pressure Hg arc) in H O /UV processes. The low or medium UV lamp alone resulted in a 60%–90% decomposition of 2,4-DCP while a slight addition of H O resulted in a drastic enhancement of the 2,4-DCP decomposition rate. The decomposition rate of 2,4-DCP with the medium pressure UV lamp alone was about 3–6 times greater than the low pressure UV lamp alone. In the direct photolysis of aqueous CCl , the medium pressure UV lamp had advantage over the low pressure UV lamp because the molar extinction coefficient of CCl at shorter wavelength (210–220 nm) is about 20 to 50 times higher than that at 254 nm. However, adding H O to the medium pressure UV lamp system rendered a negative oxidation rate because H O acted as a UV absorber being competitive with CCl due to negligible reaction between CCl and OH radicals. The results from the present study indicated significant influence of the photochemical properties of the target contaminants on the photochemical treatment characteristics for designing cost-effective UV-based degradation of toxic contaminants.

关键词： H₂O₂/ultraviolet (UV) light advanced oxidation UV light irradiation chlorinated contaminants photochemical treatment characteristics

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脉冲X射线模拟技术的发展

邱爱慈

《中国工程科学》 2000年第2卷第9期页码 24-28

摘要：

文章简要介绍了利用强流脉冲电子束加速器模拟脉冲X射线的发展概况及国内脉冲X射线模拟源的发展现状，指出作为主要技术途径，高功率Z箍缩技术在实现超强脉冲X射线源和ICF驱动源上都有很重要的发展应用前景，并提出了今后工作设想。

关键词：脉冲X射线高功率脉冲技术脉冲电子束加速器 Z箍缩 ICF

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Fabrication and in vivo evaluation of Ti6Al4V implants with controlled porous structure and complex shape

Xiang LI, Yun LUO, Chengtao WANG, Wenguang ZHANG, Yuanchao LI

《机械工程前沿（英文）》 2012年第7卷第1期页码 66-71 doi: 10.1007/s11465-012-0302-y

摘要：

Electron beam melting process was used to fabricate porous Ti6Al4V implants. The porous structure and surface topography of the implants were characterized by scanning electron microscopy (SEM) and digital microscopy (DM). The results showed that the pore size was around 600 and the porosity approximated to 57%. There was about±50 μm of undulation on implants surfaces. Standard implants and a custom implant coupled with porous sections were designed and fabricated to validate the versatility of the electron beam melting (EBM) technique. After coated with bone-like apatite, samples with fully porous structures were implanted into cranial defects in rabbits to investigate the in vivo performance. The animals were sacrificed at 8 and 12 weeks after implantation. Bone ingrowth into porous structure was examined by histological analysis. The histological sections indicated that a large amount of new bone formation was observed in porous structure. The newly formed bone grew from the calvarial margins toward the center of the bone defect and was in close contact with implant surfaces. The results of the study showed that the EBM produced Ti6Al4V implants with well-controlled porous structure, rough surface topography and bone-like apatite layer are beneficial for bone ingrowth and apposition.

关键词： electron beam melting process implant porous structure bone ingrowth

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Effect of ultraviolet irradiation and chlorination on ampicillin-resistant

Yuchen PANG,Jingjing HUANG,Jinying XI,Hongying HU,Yun ZHU

《环境科学与工程前沿（英文）》 2016年第10卷第3期页码 522-530 doi: 10.1007/s11783-015-0779-9

摘要： Antibiotic resistance is a serious public health risk that may spread via potable and reclaimed water. Effective disinfection is important for inactivation of antibiotic-resistant bacteria and disruption of antibiotic resistance genes. Ampicillin is a widely prescribed antibiotic but its effectiveness is increasingly undermined by resistance. In this study, changes in ampicillin resistance for ( ) CGMCC 1.1595 were analyzed after exposure to different doses of ultraviolet (UV) or chlorine, and damage incurred by the plasmid encoding ampicillin resistance gene was assessed. We reported a greater stability in ampicillin-resistant CGMCC 1.1595 after UV irradiation or chlorination when compared with previously published data for other strains. UV irradiation and chlorination led to a shift in the mortality frequency distributions of ampicillin-resistant when subsequently exposed to ampicillin. The ampicillin hemi-inhibitory concentration (IC ) without disinfection was 3800 mg·L , and an increment was observed after UV irradiation or chlorination. The IC of ampicillin-resistant was 1.5-fold higher at a UV dose of 40 mJ·cm , and was 1.4-fold higher when exposed to 2.0 mg·L chlorine. These results indicate that UV irradiation and chlorination can potentially increase the risk of selection for strains with high ampicillin resistance. There was no evident damage to after 1–10 mg Cl ·L chlorination, while a UV dose of 80 mJ·cm yielded a damage ratio for of approximately 1.2-log. Therefore, high UV doses are required for effective disruption of antibiotic resistance genes in bacteria.

关键词： antibiotic resistance Escherichia coli ampicillin resistance gene ultraviolet irradiation chlorination

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Use of gamma-irradiation pretreatment for enhancement of anaerobic digestibility of sewage sludge

YUAN Shoujun, ZHENG Zheng, YU Xin, ZHAO Yongfu, MU Yanyan

《环境科学与工程前沿（英文）》 2008年第2卷第2期页码 247-250 doi: 10.1007/s11783-008-0041-9

摘要： The effects of ?-irradiation pretreatment on anaerobic digestibility of sewage sludge was investigated in this paper. Parameters like solid components, soluble components, and biogas production of anaerobic digestion experiment for sewage sludge were measured. The values of these parameters were compared before and after ?-irradiation pretreatment. Total solid (TS), volatile solid (VS), suspended solid (SS), volatile suspended solid (VSS), and average floc size of samples decreased after ?-irradiation treatment. Besides, floc size distribution of sewage sludge shifted from 80–100 ?m to 0–40 ?m after ?-irradiation treatment at the doses from 0 to 30 kGy, which indicated the disintegration of sewage sludge. Moreover, microbe cells of sewage sludge were ruptured by ?-irradiation treatment, which resulted in the release of cytoplasm and increase of soluble chemical oxygen demand (SCOD). Both sludge disintegration and microbe cells rupture enhanced the subsequent anaerobic digestion process, which was demonstrated by the increase of accumulated biogas production. Compared with digesters fed with none irradiated sludge, the accumulated biogas production increased 44, 98, and 178 mL for digesters fed sludge irradiated at 2.48, 6.51, and 11.24 kGy, respectively. The results indicated that ?-irradiation pretreatment could effectively enhance anaerobic digestibility of sewage sludge, and correspondingly, could accelerate hydrolysis process, shorten sludge retention time of sludge anaerobic digestion process.

关键词： anaerobic digestibility soluble chemical cytoplasm digestion process soluble

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precise-acting” strategies for improving anaerobic methanogenesis of organic waste: Insights from the electron

《环境科学与工程前沿（英文）》 2022年第16卷第6期 doi: 10.1007/s11783-021-1508-1

摘要： Methanogenesis is the last step in anaerobic digestion, which is usually a rate-limiting step in the biological treatment of organic waste. The low methanogenesis efficiency (low methane production rate, low methane yield, low methane content) substantially limits the development of anaerobic digestion technology. Traditional pretreatment methods and bio-stimulation strategies have impacts on the entire anaerobic system and cannot directly enhance methanogenesis in a targeted manner, which was defined as “broad-acting” strategies in this perspective. Further, we discussed our opinion of methanogenesis process with insights from the electron transfer system of syntrophic partners and provided potential targeted enhancing strategy for high-efficiency electron transfer system. These “precise-acting” strategies are expected to achieve an efficient methanogenesis process and enhance the bio-energy recovery of organic waste.

关键词： Methanogenesis Anaerobic digestion Enhancing strategy Electron transfer Organic waste