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101.
This research uses high resolution mass spectrometry to compare the NSO compounds in shale extracts. Based on the study of organic hetero-atomic types and distribution, it was found nitrogen compounds were absent in the Cambrian Xiaoyanxi Formation and the Ordovician Yanxi Formation, and the DBE values were lower because of the rocks’ high maturity. O2 compounds are the main type present in the Cambrian Xiaoyanxi Formation and the Ordovician Yanxi Formation. Microbial degradation occurred in the Ordovician Yanxi Formation, and processes involving sulfate reducing bacteria might have occurred, represented the lack of O3 compounds, the relatively higher gammacerane index. 相似文献
102.
Direct analysis in real time (DART) is a recently developed ambient ionization technique for mass spectrometry to enable rapid and sensitive analyses with little or no sample preparation. After swab-based field sampling, the organothiophosphate malathion was analyzed using DART-Fourier transform ion cyclotron resonance (FT-ICR) mass spectrometry (MS) and tandem mass spectrometry (MS/MS). Mass resolution was documented to be over 800,000 in full-scan MS mode and over 1,000,000 for an MS/MS product ion produced by collision-induced dissociation of the protonated analyte. Mass measurement accuracy below 1 ppm was obtained for all DART-generated ions that belonged to the test compound in the mass spectra acquired using only external mass calibration. This high mass measurement accuracy, achievable at present only through FTMS, was required for unequivocal identification of the corresponding molecular formulae. 相似文献
103.
Mayeen Uddin Khandaker Kwangsoo KimManwoo Lee Kyung Sook KimGuinyun Kim 《Nuclear instruments & methods in physics research. Section B, Beam interactions with materials and atoms》2011,269(10):1140-1149
Production cross-sections of the residual radionuclides for the natNi(p,x)55,56,57,58 m + gCo, 56,57Ni nuclear reactions were measured up to 40 MeV by using a stacked-foil activation technique at the MC-50 cyclotron of the Korea Institute of Radiological and Medical Sciences. The results were compared with the reported experimental data as well as the theoretical calculations based on the TALYS and the ALICE-IPPE codes. The present results are in general good agreement with the other experimental data and calculated results. The integral yields for thick target were also deduced from the measured excitation functions of the produced radionuclides. The present experimental results will play an important role in enrichment of the literature data base for proton-induced reactions on natural nickel leading to various applications. 相似文献
104.
Tianjue Zhang Yinlong Lu Zhiguo Yin Junqin Zhong Tao Cui Min Li Sumin Wei Guofang Song Longcheng Wu Bin Ji Jiansheng Xing Jiuchang QinXianlu Jia Weiping HuJianjun Yang Shizhong AnFengping Guan Xia ZhenLipeng Wen Jun LinZhenguo Li Xingzhi ZhangYuexin Cai Fang Yang 《Nuclear instruments & methods in physics research. Section B, Beam interactions with materials and atoms》2011,269(24):2950-2954
Based on a 10 MeV CRM cyclotron developed at China Institute of Atomic Energy (CIAE) with an achieved beam intensity of up to 430 μA, a 14 MeV high intensity compact cyclotron, CYCIAE-14, was designed and being built at CIAE. It is planned that the first machine would be in place with a span of 2 years. CYCIAE-14 is delicately designed to realize strong vertical focusing by adopting a 4-sector, variable hill-gap structure with an external ion source to achieve high intensity. A special design applied to the stripping extraction gives access to dual extraction with four beams. The adoption of sophisticated industrial technology will give the cyclotron advantages, e.g. low power consumption and high reliability. This paper is aimed to present the overall design of the machine, including the basic technical specifications, main magnet and coils, RF, ion source and axial injection, and stripping extraction, etc. It will also give an introduction to its construction schedule as well as the up-to-date progress. 相似文献
105.
Xiaobo ZHANG 《等离子体科学和技术》2022,24(6):64007
In J-TEXT tokamak, fast electron bremsstrahlung diagnostic with 9 chords equipped with multi-channel analyzer enables detailed studies of the generation and transport of fast electrons. The spatial profiles and energy spectrum of the fast electrons have been measured in two ECCD cases with either on-axis or off-axis injection, and the profiles processed by Abel-inversion are consistent with the calculated power deposition locations. Moreover, it is observed that the energy of fast electrons increases rapidly after turning off the ECCD, which may be attributed to the acceleration by the recovered loop voltage at low electron density. 相似文献
106.
采用傅里叶变换离子回旋共振质谱(FT-ICR MS)研究沸点大于360℃的煤直接液化重油中胶质、沥青质的组成,通过在分子水平上对杂原子化合物进行表征分析胶质、沥青质中杂原子类型、碳数分布和等效双键(DBE)。结果表明,煤直接液化重油中胶质及沥青质中杂原子化合物的分子组成十分复杂,采用正离子电喷雾结合高分辨傅里叶变换离子回旋共振质谱鉴定出了N1、N1O1、N2、N2O2、N2S1 5类不同分子组成的碱性氮化物和S1、S2 2种含硫化合物;采用负离子电喷雾鉴定出了N1、N1O1、N1O2、N2、N2O1、N2O2 6类非碱性氮化物和O1、O2、O3、O4、O5、O6、O1S1、O2S1、O3S1、O4S1 10类含氧化合物,其中碱性氮化物相对丰度较高的是N1类化合物,含硫化合物相对丰度较高的是S1类化合物,非碱性氮化物相对丰度最高的是N1O2类化合物,含氧化合物相对丰度最高的是O2类化合物。根据各类化合物的DBE和碳数分布,获得了煤直接液化重油中胶质、沥青质分子组成的重要信息。碱性N1类化合物主要母核结构是吡啶和喹啉为中心官能团的化合物,非碱性N1类化合物主要母核结构是苯并咔唑,S1类化合物主要以高缩合、长侧链的稠环含硫芳烃为主,O2类化合物主要母核结构是菲二酚及蒽二酚。 相似文献
107.
采用质子回旋加速器通过natCd(p,xn)111In 核反应制备111In 。为实现从加速器辐照的天然Cd靶中提取111In ,建立使用二(2-乙基己基)磷酸萃淋树脂(CL-D2EHPA ,75~120目)色层柱法从Cd靶溶解液中提取111In 的工艺。根据In3+、Fe3+、Cu2+、Zn2+和Cd2+在盐酸或硝酸体系与50%的 CL-D2EHPA之间的分配系数,确定了使用CL-D2EHPA色层柱从天然Cd靶和靶内含有杂质核素中提取111In 的工艺:首先用 7 mol/L 硝酸将Cd、Cu、Zn穿透,再用3 mol/L 盐酸解吸111In 并收集。111In 的放化回收率大于96%,用天然Cd靶制备的111In 核纯度大于96%,化学杂质小于2 mg/L。 相似文献
108.
109.
为了提高束流在输运系统中的传输效率,改善靶点的束斑特性,本文用TRANSPORT程序对四川大学回旋加速器束流传输系统的光学特性进行了计算和分析。 TRANSPORT是采用矩阵方法计算带电粒子束在输运系统中光学特性的通用计算机程序,并能利用非线性最小二乘法和耦合系数方法对系统参数实行优化,广泛用于束流传输系 相似文献
110.
首先,详细推导了AVF型回旋加速器中束团粒子在曲线坐标系中的动力学方程(考虑和不考虑空间电荷相互作用力两种情况)。然后,在假定动力学方程中各参数值的前提条件下,用Lunge-Kutta方法对考虑空间电荷时的动力学方程进行了数值计算。结果表明,束晕的形成和发展同样也是强流回旋加速器中束流损失的一个主要原因。但束晕形成的机制不同于直线加速器的情况,它不是由共振和混沌引起,而是由于粒子的排斥运动和束团内粒子的涡流运动引起的。 相似文献