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Application of gamma-ray attenuation technology in density measurement of a slurry reactor

Jian XU, Weisheng WEI, Kai ZHANG

《化学科学与工程前沿(英文)》 2010年 第4卷 第4期   页码 486-490 doi: 10.1007/s11705-010-0509-6

摘要: Axial density profile of the gas-liquid-solid mixture in a slurry bubble column was measured by gamma-ray attenuation technology. Several measures for improving measurement precision were presented based on the discussion on attenuation law. It was found that the response frequency and the ray intensity should be as high as possible to improve the measurement precision. The mass absorption coefficient depended on not the object’s thickness but the location where the object was placed between the ray source and the detector. The results showed that the density in the column decreases with the increase of column height, which indicates that the measurement by gamma-ray attenuation is reasonable.

关键词: slurry reactor     axial density distribution     gamma-ray attenuation technology    

脉冲中子、伽马探测系统性能表征与设计技术

欧阳晓平

《中国工程科学》 2009年 第11卷 第5期   页码 44-53

摘要:

探测系统是获取辐射场特征信息的核心器件,是实施脉冲辐射探测的关键和技术基础,其性能直接决定测试数据的质量和测试方法的选择。对影响脉冲辐射探测的性能指标进行系统描述、表征是探测系统设计、研制、实际应用和综合性能评价的基础。用于复杂能谱脉冲中子、伽马混合辐射场时间谱、强度谱测量的探测系统,主要性能包括探测灵敏度、时间响应、能量响应、线性电流和中子、伽马分辨能力等指标参数,这些参数的获得与实现,需要根据中子、伽马射线与物质相互作用的基本原理,构建相应的探测结构和技术原理。在设计上,综合权衡能量收集和电荷收集方式选择、几何效率完备和高信噪比结合、信号响应和直照响应分离、探测效率与时间特性兼顾、综合性能与使用可靠性一致等设计原则,综合应用这些原则构成了探测系统设计方法。

关键词: 中子、伽马混合场     脉冲辐射探测     探测系统     设计原理     性能参数    

脉冲辐射探测技术

欧阳晓平

《中国工程科学》 2008年 第10卷 第4期   页码 44-55

摘要:

脉冲辐射探测是探知核反应过程特征信息的主要途径之一,是核反应过程特性研究、核装置设计、运行、监测与控制不可或缺的技术手段。由核探测器、探测方法和应用技术等构成的脉冲辐射场探测技术,已成为科学研究、核技术应用、核材料分析、裂变/聚变研究和天体物理等相关核科学研究的必备技术元素。文章介绍了我国发展的瞬态核裂变、核聚变反应过程释放的脉冲中子、伽马混合辐射场探测系统和测量技术。

关键词: 裂变反应     聚变反应     脉冲辐射探测     探测系统     中子测量     伽马测量    

一种新型生物材料——玉米醇溶蛋白多孔支架的质量监控

张玥, 李伟迎, 兰润, 王瑾晔

《工程(英文)》 2017年 第3卷 第1期   页码 130-135 doi: 10.1016/J.ENG.2017.01.001

摘要: 我们用SDS-PAGE 研究了三种灭菌方式对玉米醇溶蛋白多孔支架的影响,并比较了在不同γ 射线剂量下SDS-PAGE 图谱的变化。我们发现在剂量20~30 kGy 范围内,γ 射线灭菌过程中玉米醇溶蛋白的肽链没有发生断裂或聚合,这表明γ 射线灭菌对于玉米醇溶蛋白多孔支架是适用的。

关键词: 玉米醇溶蛋白     氨基酸分析     十二烷基硫酸钠&ndash     聚丙烯酰氨凝胶电泳     &gamma     射线灭菌     MTT 实验     CCK-8 实验    

微地震信号低衰减传播

肖健,孙书廷,刘建中

《中国工程科学》 2014年 第16卷 第8期   页码 83-87

摘要:

本文探讨了弱地震信号低衰减传播的可能性。结果表明,地下的地震信号传播介质均表现出一定的弹性,振动信号幅度在低于介质弹性限度时传播,衰减很小,表现出低衰减特征。这一特点保证了可以在地面,甚至黄土覆盖区监测到微地震信号。

关键词: 微地震     低衰减     非弹性衰减    

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    

microbial reductive dehalogenation with persulfate activation and oxidation (Bio-RD-PAO) for complete attenuation

《环境科学与工程前沿(英文)》 2022年 第16卷 第2期 doi: 10.1007/s11783-021-1457-8

摘要:

•Bio-RD-PAO can effectively and extensively remove organohalides.

关键词: Bio-RD-PAO     Microbial reductive dehalogenation     Persulfate     Organohalide respiration     Complete attenuation    

Attenuation mechanism of

Yuanqiang ZHENG,Yanchun SHI,Chang AN,Ruisheng LI,Dongjun LIU,Yuehua KE,Kairong MAO,Mingjuan YANG,Zeliang CHEN,Shorgan BOU

《农业科学与工程前沿(英文)》 2014年 第1卷 第4期   页码 331-340 doi: 10.15302/J-FASE-2014032

摘要: Brucellosis is a worldwide zoonosis. Vaccination is the most efficient means to prevent and control brucellosis. The current licensed attenuated vaccines for animal use were developed by sequential passage in non-natural hosts that decreased virulence in its original hosts. The attenuation mechanism of these strains remains largely unknown. In the present study, we sequenced the genome of vaccine strain M5-10. Sequence analysis showed that a large number of genetic changes occurred in the vaccine strains. A total of 2854 genetic polymorphic sites, including 2548 SNP, 241 INDEL and 65 MNV were identified. Of the 2074 SNPs in coding regions, 1310 (63.2%) were non-synonymous SNPs. Gene number, percent and N/S ratios were disproportionally distributed among the cog categories. Genetic polymorphic sites were identified in genes of the operon, flagella synthesis, and virulence regulating systems. These data indicate that changes in some cog categories and virulence genes might result in the attenuation. These attenuation mechanisms also have implications for screening and development of new vaccine strains. The genetic changes in the genome represent candidate sites for differential diagnosis between these vaccine strains and other virulence ones. Transcription analysis of virulence genes showed that expression of , were reduced in M5-10 strain when compared with that in 16M. A duplex PCR targeting and was successfully used to differentiate between M5-10 and the virulent 16M strain. The genome re-sequencing technique represents a strong strategy not only for evaluation of vaccines, but also for development of new vaccines.

关键词: Brucella     live attenuated vaccine     attenuation     differential diagnosis    

A study on quality evaluation for bituminous mixture using X-ray CT

Satoshi TANIGUCHI, Keiichiro OGAWA, Jun OTANI, Itaru NISHIZAKI

《结构与土木工程前沿(英文)》 2013年 第7卷 第2期   页码 89-101 doi: 10.1007/s11709-013-0197-7

摘要: The objective of this paper is to propose a new quality evaluation method for asphalt concrete mixture using X-ray CT scanner. To achieve this aim, asphalt mixtures should be subjected to the X-ray CT scanning and its characteristics should be clarified. The approach employed in this study was as follows: 1) Coarse aggregate, fine aggregate, filler and bitumen were prepared; 2) dense-graded, coarse-graded and porous asphalt mixtures were made; 3) materials and mixtures were subjected to the X-ray CT scanning; 4) frequency of CT-value, threshold value, average slice CT-value, average segment CT-value were computed. In the material examination, CT-value of aggregate becomes smaller in the order of coarse aggregate, fine aggregate and filler and CT image of bitumen was nearly homogeneous. In the mixture examination, histograms of CT-value and four segmentation images made from CT images expressed the material and mixture characterization such as particle size and the difference in bitumen content and mixture type visibly and the bitumen content varies with the threshold values. In addition, the average segment CT-value without threshold value by dividing the fine aggregate from the coarse aggregate and average CT-value of the coarse aggregate, especially is highly correlated with average CT-value of the bitumen.

关键词: asphalt concrete mixture     aggregate     bitumen     bitumen content     quality evaluation     X-ray CT    

Adsorption of fluoride on clay minerals and their mechanisms using X-ray photoelectron spectroscopy

Junyi DU, Daishe WU, Huayun XIAO, Ping LI

《环境科学与工程前沿(英文)》 2011年 第5卷 第2期   页码 212-226 doi: 10.1007/s11783-010-0255-5

摘要: This research investigates the adsorption mechanisms of fluoride (F) on four clay minerals (kaolinite, montmorillonite, chlorite, and illite) under different F concentrations and reaction times by probing their fluoride superficial layer binding energies and element compositions using X-ray photoelectron spectroscopy (XPS). At high F concentrations ( = 5–1000 mg·L ), the amount of F adsorbed ( ), amount of hydroxide released by clay minerals, solution F concentration, and the pH increase with increasing . The increases are remarkable at >50 mg·L . The increases significantly by continuously modifying the pH level. At <5–100 mg·L , clay minerals adsorb H to protonate aluminum-bound surface-active hydroxyl sites in the superficial layers and induce F binding. As the increases, F , along with other cations, is adsorbed to form a quasi-cryolite structure. At >100 mg·L , new minerals precipitate and the product depends on the critical Al concentration. At [Al ]>10 mol·L , cryolite forms, while at [Al ]<10 mol·L , AlF is formed. At low (0.3–1.5 mg·L ), proton transfer occurs, and the F adsorption capabilities of the clay minerals increase with time.

关键词: clay mineral     fluoride (F)     adsorption mechanism     X-ray photoelectron spectroscopy (XPS)    

Protective effects of nicotine on gamma-aminobutyric acid neurons and dopaminergic neurons in mice with

Lei FU MD , Dezheng GONG BM , Yan PENG , Dongmei WANG BM , Hong XU , Yue LI MD , Dengqin YU BS , Yanhui FENG MD , Shengming YIN PhD , Jin GONG , Yiping SUN PhD ,

《医学前沿(英文)》 2009年 第3卷 第3期   页码 330-335 doi: 10.1007/s11684-009-0051-4

摘要: This study aimed to investigate the protective effect of nicotine on dopaminergic neurons and its mechanisms in mice with Parkinson disease (PD) induced by 1-methyl-4-phenyl-1,2,3, 6-tetrahydropyridine (MPTP). C57BL/6J mice were injected with MPTP for 8 days to establish a PD model. Nicotine was given for 10 days in the nicotine therapeutic group. Animals were examined behaviorally with the pole test and traction test. Tyrosine hydroxylase (TH) and γ-aminobutyric acid (GABA) were determined by using the immunocytochemistry (ICC) method. The ultrastructural changes of the caudate nucleus (CN) were observed under electron microscopy. The results showed that pretreatment with nicotine could improve the dyskinesia of PD mice markedly. Simultaneously, TH-positive ( < 0.01) neurons and GABA-positive ( < 0.05) neurons in the nicotine therapeutic group were significantly more than those in the model group. The ultrastructural injury of the nicotine therapeutic group was also ameliorated. Nicotine has protective effects on the γ-aminobutyric acid neurons and dopaminergic neurons in the MPTP-treated mice.

关键词: Parkinson disease     nicotine     dopaminergic neuron     gamma-aminobutyric acid neuron    

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    

Optimization and modeling of coagulation-flocculation to remove algae and organic matter from surface water by response surface methodology

Ray, Ajay K Ray, Tianyin Huang, Jiabin Chen

《环境科学与工程前沿(英文)》 2019年 第13卷 第5期 doi: 10.1007/s11783-019-1159-7

摘要: Charge neutralization and sweep flocculation were the major mechanisms. Effect of process parameters was investigated. Optimal coagulation conditions were studied by response surface methodology. ANN models presented more robust and accurate prediction than RSM. Seasonal algal blooms of Lake Yangcheng highlight the necessity to develop an effective and optimal water treatment process to enhance the removal of algae and dissolved organic matter (DOM). In the present study, the coagulation performance for the removal of algae, turbidity, dissolved organic carbon (DOC) and ultraviolet absorbance at 254 nm (UV254) was investigated systematically by central composite design (CCD) using response surface methodology (RSM). The regression models were developed to illustrate the relationships between coagulation performance and experimental variables. Analysis of variance (ANOVA) was performed to test the significance of the response surface models. It can be concluded that the major mechanisms of coagulation to remove algae and DOM were charge neutralization and sweep flocculation at a pH range of 4.66–6.34. The optimal coagulation conditions with coagulant dosage of 7.57 mg Al/L, pH of 5.42 and initial algal cell density of 3.83 × 106 cell/mL led to removal of 96.76%, 97.64%, 40.23% and 30.12% in term of cell density, turbidity, DOC and UV254 absorbance, respectively, which were in good agreement with the validation experimental results. A comparison between the modeling results derived through both ANOVA and artificial neural networks (ANN) based on experimental data showed a high correlation coefficient, which indicated that the models were significant and fitted well with experimental results. The results proposed a valuable reference for the treatment of algae-laden surface water in practical application by the optimal coagulation-flocculation process.

关键词: Algae     Coagulation-flocculation     Response surface methodology     Artificial neural networks    

Establishing two-stage interaction between fly ash and NaOH by X-ray and infrared analyses

Bhagwanjee JHA,Nevin KOSHY,Devendra Narain SINGH

《环境科学与工程前沿(英文)》 2015年 第9卷 第2期   页码 216-221 doi: 10.1007/s11783-014-0630-8

摘要: The interaction of the fly ash and NaOH, in an open reflux hydrothermal system at 100°C, has been explored by several researchers and formation of fly ash zeolites has been confirmed based on the X-ray diffraction analysis of the residues. However, this method does not reveal much about the characteristic transitions (viz. elemental, electro-negativity and cation exchange capacity) of the residues. In this situation, resorting to Fourier transform-infrared radiation (FT-IR) spectroscopy on the residues obtained from two-stage hydrothermal treatment process, described in this manuscript, appears to be a novel idea to establish transitions in chemical bonds (viz., -Si-OH-Al-, OH-Na, OH-Al-), crystallinity and cation exchange capacity of these residues. Based on extensive studies, it has been demonstrated that FT-IR spectroscopy is extremely useful for 1) detection of chemical bonds in the residues, 2) evaluation of zeolites in the residues and 3) also establishing the superiority of the two-stage interaction of the fly ash with NaOH for synthesizing better fly ash zeolites (viz., Na-P1 and Hydroxysodalte) as compared to those obtained from the conventional single-stage treatment of the fly ash.

关键词: hydrothermal treatment     alkali activation     fly ash zeolites     X-ray diffraction (XRD) and Fourier transform-infrared radiation (FT-IR) spectroscopy    

用于16.7 MeV脉冲高能γ探测的散射吸收方法研究

谭新建,欧阳晓平,王群书

《中国工程科学》 2009年 第11卷 第8期   页码 48-51

摘要:

理论分析计算的基础上,提出了基于康普顿效应的散射吸收探测方法,该方法能实现高低能&gamma;灵敏度比值达106~108,且对高能&gamma;灵敏度较大,为10-21~10-16 C·cm2,其性能指标在一定程度上优于目前使用的基于磁分析器与Cherenkov探测器的高能&gamma;探测方法指标。

关键词: 高能γ     切伦柯夫探测器     散射吸收法    

标题 作者 时间 类型 操作

Application of gamma-ray attenuation technology in density measurement of a slurry reactor

Jian XU, Weisheng WEI, Kai ZHANG

期刊论文

脉冲中子、伽马探测系统性能表征与设计技术

欧阳晓平

期刊论文

脉冲辐射探测技术

欧阳晓平

期刊论文

一种新型生物材料——玉米醇溶蛋白多孔支架的质量监控

张玥, 李伟迎, 兰润, 王瑾晔

期刊论文

微地震信号低衰减传播

肖健,孙书廷,刘建中

期刊论文

脉冲X射线模拟技术的发展

邱爱慈

期刊论文

microbial reductive dehalogenation with persulfate activation and oxidation (Bio-RD-PAO) for complete attenuation

期刊论文

Attenuation mechanism of

Yuanqiang ZHENG,Yanchun SHI,Chang AN,Ruisheng LI,Dongjun LIU,Yuehua KE,Kairong MAO,Mingjuan YANG,Zeliang CHEN,Shorgan BOU

期刊论文

A study on quality evaluation for bituminous mixture using X-ray CT

Satoshi TANIGUCHI, Keiichiro OGAWA, Jun OTANI, Itaru NISHIZAKI

期刊论文

Adsorption of fluoride on clay minerals and their mechanisms using X-ray photoelectron spectroscopy

Junyi DU, Daishe WU, Huayun XIAO, Ping LI

期刊论文

Protective effects of nicotine on gamma-aminobutyric acid neurons and dopaminergic neurons in mice with

Lei FU MD , Dezheng GONG BM , Yan PENG , Dongmei WANG BM , Hong XU , Yue LI MD , Dengqin YU BS , Yanhui FENG MD , Shengming YIN PhD , Jin GONG , Yiping SUN PhD ,

期刊论文

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

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

期刊论文

Optimization and modeling of coagulation-flocculation to remove algae and organic matter from surface water by response surface methodology

Ray, Ajay K Ray, Tianyin Huang, Jiabin Chen

期刊论文

Establishing two-stage interaction between fly ash and NaOH by X-ray and infrared analyses

Bhagwanjee JHA,Nevin KOSHY,Devendra Narain SINGH

期刊论文

用于16.7 MeV脉冲高能γ探测的散射吸收方法研究

谭新建,欧阳晓平,王群书

期刊论文