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关键词

医院中子照射器I型堆 6

医院中子照射器 5

应力 3

应力状态 3

残余应力 3

DX桩 2

中子通量密度 2

应力波 2

强度理论 2

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硼中子俘获疗法 2

ACE格式 1

BNCT 1

BNCT医院中子照射器 1

BPA 1

CITATION 1

D1 turnover / photoinhibition / photoprotection / photosynthesis / tomato / xanthophyll cycle 1

ENDF/B VII.0评价库 1

H2S应力腐蚀 1

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Air bearing center cross gap of neutron stress spectrometer sample table support system

Yang LI,Yunxin WU,Hai GONG,Xiaolei FENG

《机械工程前沿（英文）》 2016年第11卷第4期页码 403-411 doi: 10.1007/s11465-016-0405-y

摘要：

A support system is the main load-bearing component of sample table for neutron stress spectrometer, and air bearing is an important element of a support system. The neutron stress spectrometer sample table was introduced, and the scheme for air bearing combination was selected. To study the performance of air bearing center cross gap, finite element models (FEMs) were established based on air motion and Reynolds equations, effects of air supply pressure, and gap parameters on the overturning moment and bearing capacity of air bearing center cross gap were analyzed. Results indicate that the width, depth, and height differences of the marble floor gap played important roles in the performance of the air bearing. When gap width is lesser than 1 mm and gap depth is lower than 0.4 mm, bearing capacity and overturning moment would vary rapidly with the variation of the width and depth. A gap height difference results in the bearing capacity dropping rapidly. The FEM results agree well with experimental results. Further, findings of the study could guide the design of the support system and marble floor.

关键词： neutron stress spectrometer sample table support system air bearing center cross gap simulation experiment

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Review on the applications of Tropospheric Emissions Spectrometer to air-quality research: Perspectives

Yuxuan WANG, Yuqiang ZHANG, Jiming HAO,

《环境科学与工程前沿（英文）》 2010年第4卷第1期页码 12-19 doi: 10.1007/s11783-010-0012-9

摘要： The Tropospheric Emissions Spectrometer (TES) aboard the National Aeronautics and Space Administration’s (NASA’s) Aura satellite launched in July 2004 is the first satellite instrument to provide simultaneous retrievals of ozone (O) and carbon monoxide (CO) throughout the Earth’s lower atmosphere. This paper briefly reviews the TES instrument, the retrieval of O and CO profiles, and the validation of the retrievals. The applications of TES O and CO products include mapping the vertical and horizontal distribution of tropospheric O and CO and their correlations, examining the regional and continental outflow, and analyzing the variability of the two species associated with certain weather and climatic conditions, such as El Niño and the Asian monsoon. TES retrievals of O and CO offer an important new source of satellite data over China with good spatial and temporal coverage that can provide evaluation and constraints on the performance of chemical transport models in simulating the general features of ozone pollution over China. Special observations have been conducted and requests may be submitted to the TES team to make geographically focused observations of O and CO over China.

关键词： Tropospheric Emissions Spectrometer (TES) ozone carbon monoxide China

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A spectrometer for measuring particle size distributions in the range of 3 nm to 10 μm

Jieqiong LIU,Jingkun JIANG,Qiang ZHANG,Jianguo DENG,Jiming HAO

《环境科学与工程前沿（英文）》 2016年第10卷第1期页码 63-72 doi: 10.1007/s11783-014-0754-x

摘要： A spectrometer combining electrical mobility sizing and aerodynamic sizing was developed to measure aerosol size distributions in the range of 3 nm to 10 μm. It includes three instruments which cover different size ranges (a nano scanning mobility particle sizer (NSMPS, 3 – 60 nm), a regular scanning mobility particle sizer (RSMPS, 40 – 700 nm), and an aerodynamic particle sizer (APS, 550 nm – 10 μm)). High voltage and sheath flow of the NSMPS and RSMPS were supplied using two home-built control boxes. A LabVIEW program was developed for spectrometer automatic operation. A linear inversion method was applied to correct particle multiple charging effects and to integrate data from the three instruments into a wide-range size distribution. Experiments were conducted to compare distributions in the overlap size ranges measured by three instruments. Good agreement between the NSMPS and RSMPS was achieved after correcting for the difference in counting efficiencies of the two particle counters. Aerodynamic size distributions reported by the APS were converted to mobility size distributions by applying an effective density method. Distributions measured by the RSMPS and APS were consistent in the overlap size range of 550 – 700 nm. A full spectrum in the size range of 3 nm to 10 μm was demonstrated by measuring aerosol generated using a mixture of different sized polystyrene latex spheres.

关键词： spectrometer particle size distribution electrical mobility linear inversion aerodynamic diameter

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医院中子照射器I型堆超热中子束流孔道的优化设计

江新标,朱养妮,赵柱民,陈立新,周永茂

《中国工程科学》 2012年第14卷第8期页码 33-37

摘要：

采用蒙特卡罗程序(Monte Carlo neutron and photo transport code, MCNP)对医院中子照射器I

关键词：医院中子照射器I型堆超热中子束流中子通量密度

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Identify the contribution of vehicle non-exhaust emissions: a single particle aerosol mass spectrometer

《环境科学与工程前沿（英文）》 2023年第17卷第5期 doi: 10.1007/s11783-023-1662-8

摘要：

● A single particle observation was conducted in a high traffic flow road environment.

关键词： Non-exhaust emissions SPAMS PMF Roadside environment

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BNCT医院中子照射器辐射场特性参数初步测量

陈军,李春娟,宋明哲,李玮,姚顺和,刁立军,姚艳玲,张紫竹,高集金,张韏凡

《中国工程科学》 2012年第14卷第8期页码 106-112

摘要：

为验证BNCT医院中子照射器的设计效果，对其辐射场的特性参数如中子能谱、中子通量密度及其空间分布、中子和γ吸收剂量率及其空间分布等进行了测量。针对该照射器的特点，建立了一套由多球谱仪、235U裂变电离室、金箔、组织等效正比计数器和热释光探测器组成的测量系统，利用蒙特卡洛计算方法优化设计探测器的结构，以提高超热能区的分辨率和甄别不同能量成分中子的能力。初步测量结果表明，该照射器的中子通量密度达到了预期设计要求。

关键词： BNCT医院中子照射器中子能谱中子通量密度中子和γ吸收剂量率

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Transmission probability method based on triangle meshes for solving the unstructured geometry neutron

WU Hongchun, LIU Pingping, ZHOU Yongqiang, CAO Liangzhi

《能源前沿（英文）》 2007年第1卷第2期页码 158-166 doi: 10.1007/s11708-007-0020-z

摘要： The fuel assembly or core with unstructured geometry is frequently used in the advanced reactor. To calculate the fuel assembly, the transmission probability method (TPM) is widely used. However, the rectangular or hexagonal meshes are mainly used in the TPM codes for the normal core structure. The triangle meshes are most useful for expressing the complicated unstructured geometry. Even though the finite element method and Monte-Carlo method are well suited for solving the unstructured geometry problem, they are very time-consuming. Therefore, a TPM code based on the triangle meshes is developed here. This code was applied to the hybrid fuel geometry, and compared with the results of the MCNP code and other codes. The results of the comparison were consistent with each other. The TPM with triangle meshes can thus be applied to the two-dimensional arbitrary fuel assembly.

关键词： unstructured geometry assembly transmission probability TPM rectangular

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医院中子照射器I型堆热中子束流孔道等效平面源的模拟计算

朱养妮,江新标,赵柱民,张良,周永茂

《中国工程科学》 2012年第14卷第8期页码 56-59

摘要：

采用蒙特卡罗程序MCNP模拟计算了医院中子照射器I型堆（IHNI-1）热中子束流孔道出口处的等效平面源。对B堆芯进行了临界搜索计算，模拟计算了热中子束流孔道及出口处中子、γ的束流参数，应用等效平面源模型建立了BNCT等效中子、γ平面源。为人体头颅等效模型剂量分布的快速计算提供了较为可靠的平面源。

关键词：医院中子照射器I型堆热中子束流孔道等效中子平面源等效γ平面源

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叶酸靶向含硼脂质体的制备及其包封率的测定

王志会,钱林学,刘冬

《中国工程科学》 2012年第14卷第8期页码 78-81

摘要：

制备具有良好靶向性及包封率高的硼脂质体,为硼中子俘获治疗方法的研究与应用建立了一个有效的靶向给药途径。采用复乳法及薄膜—超声分散法制备叶酸靶向硼脂质体, 利用高效液相色谱法检测4—羟基苯硼酸4—Hydroxyphenylboronicacid（HBA）脂质体、2—噻吩硼酸2—thiophenylboric acid（TBA）脂质体、4—叔丁基苯硼酸4—tert-Butylphenylboronic Acid（BBA）脂质体的含量及包封率，以包封率为评价指标，采用单因素法优化脂质体的制备处方和工艺条件。筛选出HBA、TBA、BBA最优的色谱条件，分别绘制出标准曲线，结果表明在1~100 μg/mL范围内线性关系良好。HBA、TBA、BBA脂质体在最优制备处方和工艺条件下包封率分别为25.7 %、38.9 %、94.8 %。BBA 脂质体优化后的制备处方和工艺条件如下：胆固醇与磷脂质量比为 1∶1，药脂比为 1∶50，pH值为7.4，按该处方工艺制备的BBA 脂质体包封率在94.8 %。制备叶酸靶向脂质体的优选处方和制备工艺稳定可行，质量控制方法简单、准确, 包封率高。

关键词：硼中子俘获治疗脂质体叶酸靶向包封率

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迈入新世纪的硼中子俘获疗法（BNCT）

周永茂

《中国工程科学》 2012年第14卷第8期页码 4-13

摘要：

扼要叙述进入21世纪之际，硼中子俘获疗法（boron neutorn capture therapy，BNCT）在国际范围内的一些显著进展，包括BNCT的临床定位、肿瘤复发的探索、硼浓度的定量探测、靶向掺硼药物的开发以及我国医院中子照射器的问世。这些BNCT长期开发中的瓶颈趋于缓解，预示了BNCT个性化与例行化的前景更为清晰。

关键词：中子俘获疗法临床试治肿瘤复发硼浓度探测靶向药物医院中子照射器

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Discrete ordinates method for three-dimensional neutron transport equation based on unstructured-meshes

JU Haitao, WU Hongchun, YAO Dong, XIAN Chunyu

《能源前沿（英文）》 2008年第2卷第2期页码 179-182 doi: 10.1007/s11708-008-0024-3

摘要： A discrete ordinates method for a three-dimensional first-order neutron transport equation based on unstructured-meshes that avoids the singularity of the second-order neutron transport equation in void regions was derived. The finite element variation equation was obtained using the least-squares method. A three-dimensional transport calculation code was developed. Both the triangular-z and the tetrahedron elements were included. The numerical results of some benchmark problems demonstrated that this method can solve neutron transport problems in unstructured-meshes very well. For most problems, the error of the eigenvalue and the angular flux is less than 0.3% and 3.0% respectively.

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Application of spectral technology in flame measurement

Jiaxun LIU, Xiaoshu CAI, Zenghao ZHU, Huinan YANG

《能源前沿（英文）》 2014年第8卷第1期页码 138-143 doi: 10.1007/s11708-013-0283-5

摘要： Spectral technology has become an important detection method due to its advantages such as non-intrusive measurement and on-line analysis. In this paper, two applications of spectral technology in thermal detection were proposed. First, a novel spectroscopic method based on Planck’s law for measurement of emissivity was introduced. The emissivity, obtained by comparing the radiation intensity of the blackbody which had the same temperature as the flame with the detected intensity of the flames, could be used for on-line measurements and had a relatively higher upper temperature limit. Then, a spectroscopic method for composition detection of blended fuels was proposed based on the emissivity measured. By comparing the spectra of blended fuels and single fuels, the ratio of single fuels of the blended fuel could be calculated. The measurement system proposed in this paper, which consists of a spectrometer and a computer, is very compact.

关键词： spectrum emissivity measurement component of fuel near-infrared spectrometer

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DyFe₁₁Ti磁结构及其自旋重取向的中子衍射研究 Article

Olivier Isnard, Eder J. Kinast

《工程（英文）》 2020年第6卷第2期页码 153-157 doi: 10.1016/j.eng.2019.11.009

摘要：

本文报道了通过中子粉末衍射探测DyFe₁₁Ti的磁结构及其热演化规律。使用了变温中子衍射技术来测量磁矩及其取向的温度依赖性。Dy和Fe磁矩以反向平行的方式形成亚铁磁性耦合，其2 K时的易磁化方向是基面(a, b)内的[110]轴。随着温度的升高，该磁结构先后经历了两次自旋重取向现象。低温下，Dy磁矩较大，达到9.7μ_B，而在200 K时磁矩迅速下降到7.5μ_B。在Fe 8i位置观察到了最大的Fe磁矩。尽管磁结构发生了很大的变化，但在研究的温度范围内ThMn₁₂型晶体结构一直保持不变。在第一阶段的自旋重取向温度（T_SR1）时，观察到了易磁化轴的急剧倾斜；易磁化轴与晶体c轴之间的夹角从2 K的90°减小到200 K时的约20°（其中c轴是200 K以上的易磁化轴）；同时Dy和Fe磁矩保持反向平行耦合。

关键词：中子衍射，磁相图，晶体结构

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lipophilic penetration enhancers on the nano-structure of stratum corneum model membranes studied using neutron

Annett SCHROETER, Tanja ENGELBRECHT, Reinhard H. H. NEUBERT

《化学科学与工程前沿（英文）》 2013年第7卷第1期页码 29-36 doi: 10.1007/s11705-013-1302-0

摘要： Oriented stratum corneum model lipid membranes were used to study the influence of the short chain ceramides (CER)[NP] and [AP] as well as the impact of the lipophilic penetration enhancer molecules oleic acid (OA) and isopropyl myristate (IPM) on the lipid nanostructure. The influence of the enhancer molecules were studied using specifically deuterated OA and IPM and neutron diffraction. H NMR spectroscopy was used to study the impact of the ceramides’ degree of order within the stratum corneum model lipid membranes. It was found that CER[NP] forms two very stable phases with high resistance against temperature increase. Phase B showed unusual hydration behavior as no water uptake of this phase was observed. The H NMR spectroscopic measurements showed that CER[NP] based ternary model system had a higher state of lamellar order in comparison to CER[AP] based lipid matrix. The studies confirmed that the short chain ceramides, particularly CER[NP], have a very high impact on the integrity of the Stratum corneum lipid bilayers. The penetration enhancer OA has not influenced the repeat distance of the model membrane based on CER[AP], and was not able to induce a phase separation in the investigated lipid matrix. However, a disorder and a fluidisation of the model membranes were observed when OA was incorporated. IPM showed the same effect but two phases (assigned as phase A and B) appeared, when IPM was used as penetration enhancer and incorporated into the model membrane. Furthermore, two arrangements of IPM were identified in phase A using deuterated IPM. A model of the nanostructure of the Stratum corneum lipid membranes is presented.

关键词： nano-structure of the stratum corneum ceramide penetration enhancer model membrane neutron diffraction ²H NMR spectroscopy

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医院中子照射器性能与特性

李义国,夏普,彭旦,邹淑芸,吴小波,张金花, 张紫竹,高集金,王理玉,付金树,刘彤,周永茂

《中国工程科学》 2012年第14卷第8期页码 20-22

摘要：

介绍了医院中子照射器及其相关系统的设计情况，描述了医院中子照射器的性能和特性。为验证医院中子照射器的固有安全特性，进行了4.2 mk反应性释放实验。实验结果表明，反应堆功率快速上升，在229 s时，功率达到85.7 kW峰值，随后，由于燃料元件多普勒效应和慢化剂的负温度效应会非能动地把功率限制在允许的安全水平之下。满功率运行时，各个工艺房间γ剂量率小于1 μSv/h，且中子剂量率为本底水平，具有低辐射特点。

关键词：医院中子照射器硼中子俘获治疗固有安全特性