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医院中子照射器I型堆 6

医院中子照射器 5

硼中子俘获治疗 3

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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 neutrondiffraction

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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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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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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采用白光X射线源和模拟阵列能量色散阵列探测器的高通量粉末衍射技术 Article

汪晓平, 董伟伟, 张鹏, 唐浩琪, 张澜庭, 杨铁莹, 刘鹏, 汪洪, 项晓东

《工程（英文）》 2022年第10卷第3期页码 81-88 doi: 10.1016/j.eng.2021.05.023

摘要：

在上海同步辐射光源（SSRF）的弯铁光束线上，利用由空间扫描硅漂移探测器（SDD）模拟获得的能量色散阵列探测器，对CeO₂样品进行高通量白光X射线粉末衍射（pXRD）实验。考虑到与实验硬件和衍射角相关的多种因素，对数据进行了详细分析和校正。校正后的衍射图谱表明，由能量色散X 射线衍射（EDXRD）获得的不同衍射峰之间的相对强度与来自角度分辨X射线衍射（ARXRD）的相对强度一致，说明EDXRD结果可用于分析未知样品的晶体结构。实验同时采集了X射线荧光（XRF）信号。来自所有像素的XRF计数可直接在能量坐标下叠加，而衍射信号则需在d 空间下叠加，从而大大改善了阵列探测器的峰值强度和信噪比（S/N）。与ARXRD相比，白光X射线衍射信号强度是单色光衍射信号强度的10⁴倍左右。q 空间中衍射峰的半峰全宽（FWHM）取决于探测器的能量分辨率、探测器接收角范围和衍射角大小。如果实验参数选择得当，在当前能量色散探测器的能量分辨率下，EDXRD有可能实现与ARXRD相同甚至更小的半峰全宽。

关键词：高通量实验白光X射线衍射能量色散阵列探测器能量色散X射线衍射角分辨X射线衍射

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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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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

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分群结构对IHNI-1堆动态参数计算结果的影响研究

张良,赵柱民,江新标,陈伟,周永茂

《中国工程科学》 2012年第14卷第8期页码 47-50

摘要：编制了动态参数计算程序CKPWC（calculating kinetic parameters based on WIMS and CITATION），对医院中子照射器I型堆（in hospital neutron

关键词：医院中子照射器I型堆动态参数缓发中子有效份额中子代时间

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Development of MCBurn and its application in the analysis of SCWR physical characteristics

Ganglin YU , Kan WANG ,

《能源前沿（英文）》 2009年第3卷第3期页码 348-352 doi: 10.1007/s11708-009-0031-z

摘要： The MCBurn, a coupled code system linking the Monte Carlo N-particle transport code(MCNP) and Oak Ridge isotope generation and depletion code (ORIGEN), can resolve the basic calculation problems in reactor physical design and analysis, such as criticality, power distribution, nuclide burn up, and neutron fluence. It has been verified in the pressurized water reactor (PWR) pin model, fast reactor (FR) burn up model, and boiling water reactor(BWR) assemble model with benchmarked results. In supercritical water reactor (SCWR) physical calculations, the calculation conditions such as the geometry, the neutron spectrum, and the fuel materials, etc., are more complex than those in traditional reactors, which is a great challenge to reactor physics calculation code. However, the MCBurn code is a possible solution. In this paper, several update functions of the MCBurn in new neutron cross-section lib, code interface, and neutron flux distribution were described. The application of the MCBurn in SCWR were verified on a supercritical water reactor assemble. The calculation results show that the MCBurn is accurate and adaptable in the SCWR calculation.

关键词： Monte Carlo method MCBurn SCWR neutron cross-section lib

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波浪与外壁透空双筒柱的互相作用

滕斌,李玉成,孙路

《中国工程科学》 2001年第3卷第10期页码 41-47

摘要：

对于波浪与透空外壁同轴双筒柱的相互作用问题，利用速度势的特征函数展开式和透空壁内流体速度与两壁间压力差成正比的线性模型，建立了一个线性解析解。应用这一模型开展了数值实验，用以检验孔隙系数和透空部分大小以及内外柱径之比对双筒柱上波浪力和波面高度的影响。计算结果表明，外壁孔隙系数和透空部分大小对波面升高和波浪荷载有很大影响，通过调整各个系数，应用双筒透空柱可以减小周围的波面高度及其上的波浪荷载。

关键词：波浪绕射波浪力波面升高有孔建筑圆柱