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Prompt fission neutron uranium logging(Ⅱ):dead-time effect of the neutron time spectrum

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Nuclear Science and Techniques 2025年第2期36卷 82-94页

作者： Yan Zhang Chi Liu Shi-Liang Liu Hao-Ran Zhang Hai-Tao Wang Jin-hui Qu wen-Xing hu Ren-Bo Wang Bin Tang National Key Laboratory of Uranium Resources Exploration-Mining and Nuclear Remote Sensing East China University of TechnologyNanchang 330013China Fundamental Science on Radioactive Geology and Exploration Technology Laboratory East China University of TechnologyNanchang 330013China

The acquisition of neutron time spectrum data plays a pivotal role in the precise quantification of uranium via prompt fission neutron uranium logging(PFNUL).However,the impact of the detector dead-time effect remains paramount in the accurate acquisition of the neutron time ***,it is imperative for neutron logging instruments to establish a dead-time correction method that is not only uncomplicated but also practical and caters to various logging *** study has formulated an innovative equation for determining dead time and introduced a dead-time correction method for the neutron time spectrum,called the“dual flux method.”Using this approach,a logging instrument captures two neutron time spectra under disparate neutron *** carefully selecting specific“windows”on the neutron time spectrum,the dead time can be accurately *** substantiate its efficacy and discern the influencing factors,experiments were conducted utilizing a deuterium-tritium(D-T)neutron source,a Helium-3(3He)detector,and polyethylene shielding to collate and analyze the neutron time spectrum under varying neutron fluxes(at high voltages).The findings underscore that the“height”and“spacing”of the two windows are the most pivotal influencing ***,the“height”(fd)should surpass 2,and the“spacing”twd should exceed 200μ*** dead time of the 3 He detector determined in the experiment was 7.35μ*** the dead-time correction,the deviation of the decay coefficients from the theoretical values for the neutron time spectrum under varying neutron fluxes decreased from 12.4%to within 5%.Similarly,for the PFNUL instrument,the deviation in the decay coefficients decreased from 22.94 to 0.49%after correcting for the dead-time *** results demonstrate the exceptional efficacy of the proposed method in ensuring precise uranium *** dual flux method was experimentally validated as a universal approach applicable to pulsed neutron logging instrumen

关键词： PFNUL Neutron time spectrum Dead time Pulsed source Correction method

Multi-perception large kernel convnet for efficient image super-resolution

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四川大学学报(自然科学版) 2025年第1期62卷 67-78页

作者： MIAO xuan LI Zheng XU wen-Zheng College of Computer Science(College of Software) Sichuan UniversityChengdu 610065China Tianfu Engineering-Oriented Numerical Simulation&Software Innovation Center Sichuan UniversityChengdu 610207China

Significant advancements have been achieved in the field of Single Image Super-Resolution(SISR)through the utilization of Convolutional Neural Networks(CNNs)to attain state-of-the-art *** efforts have explored the incorporation of Transformers to augment network performance in ***,the high computational cost of Transformers makes them less suitable for deployment on lightweight ***,the majority of enhancements for CNNs rely predominantly on small spatial convolutions,thereby neglecting the potential advantages of large kernel *** this paper,the authors propose a Multi-Perception Large Kernel convNet(MPLKN)which delves into the exploration of large kernel ***,the authors have architected a Multi-Perception Large Kernel(MPLK)module aimed at extracting multi-scale features and employ a stepwise feature fusion strategy to seamlessly integrate these *** addition,to enhance the network's capacity for nonlinear spatial information processing,the authors have designed a Spatial-Channel Gated Feed-forward Network(SCGFN)that is capable of adapting to feature interactions across both spatial and channel *** results demonstrate that MPLKN outperforms other lightweight image super-resolution models while maintaining a minimal number of parameters and FLOPs.

关键词： Single Image Super-Resolution Lightweight model Deep learning Large kernel

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台湾西南部乌山顶泥火山的成因机制初探

岩石矿物学杂志 2009年第5期28卷 465-472页

作者：朱婷婷陆现彩祝幼华胡文瑄南京大学地球科学与工程学院江苏南京210093 中国科学院南京地质古生物研究所江苏南京210008

乌山顶泥火山位于台湾西南部旗山断层沿线。由于台湾西南部具有独特的地质构造背景,沿着古亭坑背斜和旗山断层沿线分布了许多泥火山。本文以乌山顶泥火山为例,研究泥火山的成因。在了解泥火山地质背景、活动现状的基础上,分析了喷出物... 详细信息

乌山顶泥火山位于台湾西南部旗山断层沿线。由于台湾西南部具有独特的地质构造背景,沿着古亭坑背斜和旗山断层沿线分布了许多泥火山。本文以乌山顶泥火山为例,研究泥火山的成因。在了解泥火山地质背景、活动现状的基础上,分析了喷出物的矿物组成、古生物组合、流体地球化学特征。喷出的主要矿物有石英、伊利石、高岭石-蒙脱石混层矿物、伊利石-蒙脱石混层矿物,古生物有Reticulofenestra minuta、Sphenolithus abies等,流体中的离子主要是Cl-、Na+等。由此探讨了泥浆来源和成因机制,认为泥火山的活动与深部古亭坑组地层存在异常高压有关,构造活动是泥火山活动的主要诱发因素。

关键词：泥火山成因机制异常高压乌山顶台湾地区

Self-reporting hypoxia-responsive supramolecular phototheranostic nanomaterials based on AIEgen and azocalixarene

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关键词： Hypoxia is a significant feature in most of solid tumors. Hence, developing hypoxia-responsive phototheranostic system is still a challenge. In this contribution, a supramolecular assembly strategy based on sulfonate-functionalized azocalixarene(SAC4A)and cationic aggregation-induced emission photosensitizer(namely TPA-H) was proposed for hypoxia-responsive bioimaging and photodynamic therapy(PDT). Upon supramolecular complexation of TPA-H and SAC4A through electrostatic interaction,the fluorescence and reactive oxygen species(ROS) generation of TPA-H were largely inhibited. In hypoxic tumors, the azo group of SAC4A can be reduced to aniline derivative and release the included TPA-H to recover its pristine fluorescence and ROS. Interestingly, the free TPA-H undergoes cell membrane-to-mitochondria translocation during cell imaging, achieving a real-time self-reporting PDT system. In vivo tumor imaging and therapy reveal that this as-prepared supramolecular complexes have good biosafety and efficient antitumor activity under hypoxia. Such hypoxia-responsive supramolecular photosensitizer system will enrich image-guided photodynamic therapy.

Science China Chemistry 2025年

作者： Xiao-wen Han Guo-Ling Zhang Pu Chen Jing Zhang Guo-Gang Shan Chun-xuan Qi Ben-Zhong Tang Hai-Tao Feng AIE Research Center Shaanxi Key Laboratory of Phytochemistry College of Chemistry and Chemical Engineering Baoji University of Arts and Sciences National & Local United Engineering Laboratory for Power Batteries Department of Chemistry Northeast Normal University School of Science and Engineering Shenzhen Institute of Aggregate Science and Technology The Chinese University of Hong KongShenzhen (CUHK-Shenzhen)

Hypoxia is a significant feature in most of solid tumors. Hence, developing hypoxia-responsive phototheranostic system is still a challenge. In this contribution, a supramolecular assembly strategy based on sulfonate-functionalized azocalix[4]arene(SAC4A)and cationic aggregation-induced emission photosensitizer(namely TPA-H) was proposed for hypoxia-responsive bioimaging and photodynamic therapy(PDT). Upon supramolecular complexation of TPA-H and SAC4A through electrostatic interaction,the fluorescence and reactive oxygen species(ROS) generation of TPA-H were largely inhibited. In hypoxic tumors, the azo group of SAC4A can be reduced to aniline derivative and release the included TPA-H to recover its pristine fluorescence and ROS. Interestingly, the free TPA-H undergoes cell membrane-to-mitochondria translocation during cell imaging, achieving a real-time self-reporting PDT system. In vivo tumor imaging and therapy reveal that this as-prepared supramolecular complexes have good biosafety and efficient antitumor activity under hypoxia. Such hypoxia-responsive supramolecular photosensitizer system will enrich image-guided photodynamic therapy.

一种新的热台温度校准方法:硫酸盐-水体系液-液相分离原位观测

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地球化学 2017年第4期46卷 319-332页

作者：王晓宇王小林万野胡文瑄南京大学地球科学与工程学院江苏南京210023 南京大学能源科学研究院江苏南京210023

以MgSO_4、ZnSO_4、CdSO_4和Li_2SO_4-H_2SO_4溶液为例,描述了熔融毛细硅管中硫酸盐-水体系的高温液-液相分离现象,即均一的溶液相分离为富集硫酸盐和贫硫酸盐的两个液相。相行为观测和原位拉曼光谱分析表明,金属离子和SO_4^(2–)之间... 详细信息

以MgSO_4、ZnSO_4、CdSO_4和Li_2SO_4-H_2SO_4溶液为例,描述了熔融毛细硅管中硫酸盐-水体系的高温液-液相分离现象,即均一的溶液相分离为富集硫酸盐和贫硫酸盐的两个液相。相行为观测和原位拉曼光谱分析表明,金属离子和SO_4^(2–)之间复杂的络合作用是导致液-液相分离发生的主要原因。首先,液-液相分离的发生温度在低浓度溶液中随浓度升高而降低,而在高浓度溶液中则随浓度升高而升高,并呈现典型的临界相转变现象,而临界相转变现象是聚合物溶液的典型宏观特征;其次,ν_1(SO_4^(2–))光谱随温度升高逐渐变宽,且不对称性加强,表明离子络合作用随温度升高而加强。以MgSO_4水/重水溶液为例,随着温度升高,先后在溶液相中检出"自由"SO_4^(2–)(~980 cm^(–1))、接触离子对MgSO_40(~992 cm^(–1))和三离子离子对Mg_2SO_4^(2+)(~1003 cm^(–1))的信号,而相分离发生后在富集硫酸盐的液相中检测到位于~1020 cm^(–1)新的ν_1(SO_4^(2–))组分,其代表了更为复杂的Mg^(2+)-SO_4^(2–)络合物。关于Mg^(2+)-SO_4^(2–)络合作用和硫酸盐-水体系液-液相分离的研究,有助于深化白云岩成因和海底热液系统中SO_4^(2–)在多孔岩石中迁移及还原为S2–的研究。受溶液组分影响,硫酸盐溶液呈现较为宽广的液-液相分离发生温度范围(150~360℃),对特定组分的硫酸盐溶液来讲,液-液相分离发生温度可重复性强,能够作为热台温度校准的标样。结合熔融毛细硅管合成流体包裹体技术,提出了一种新的热台温度校准方法。

关键词：硫酸盐水溶液液-液相分离原位观测热台温度校准

沉积盆地内侵入岩席对富含有机质围岩热影响的热传输模型研究

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南京大学学报（自然科学版） 2011年第1期47卷 45-50页

作者：王大勇陆现彩徐士进胡文瑄齐天大连理工大学能源与动力学院海洋能源利用与节能教育部重点实验室大连116023 南京大学地球科学系南京210093

以澳大利亚Gunnedah盆地Bellata-1井作为实例,采用3种主要的热传导模型,数值模拟了火成侵入岩席对相邻烃源岩的热影响.结果表明:(1)假设岩浆瞬间侵入且考虑地层孔隙水气化的复杂热传导模型估计的围岩的接触温度最高,假设岩浆瞬间侵入但... 详细信息

以澳大利亚Gunnedah盆地Bellata-1井作为实例,采用3种主要的热传导模型,数值模拟了火成侵入岩席对相邻烃源岩的热影响.结果表明:(1)假设岩浆瞬间侵入且考虑地层孔隙水气化的复杂热传导模型估计的围岩的接触温度最高,假设岩浆瞬间侵入但忽略地层孔隙水气化的简单热传导模型次之,而假设岩浆缓慢侵入的简单热传导模型的估计值最低.(2)岩浆瞬间侵入的简单热传导模型预测的岩席对围岩的热影响范围最高,缓慢侵入的热传导模型最低,岩浆的缓慢侵入方式在降低侵入体对相邻围岩的热影响方面,可以比孔隙水的气化作用更为显著.(3)岩浆瞬间侵入的简单热传导模型的计算结果与镜质体反射率温标最为吻合,说明岩浆为瞬间侵入且孔隙水的气化及流动在低渗透率且超高压的地层内受到了限制.

关键词：岩浆侵入体热传输模型热演化 Gunnedah盆地

Andreev reflection in superconducting state of pressurized La3Ni2O7

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Science China(Physics,Mechanics & Astronomy) 2025年第04期Mechanics & Astronomy) .卷 184-192页

作者： Cong Liu Mengwu huo huan Yang Qing Li Yingjie Zhang Zhening Xiang Meng Wang Hai-hu wen National Laboratory of Solid State Microstructures and Department of Physics Collaborative Innovation Center of Advanced MicrostructuresNanjing University Center for Neutron Science and Technology Guangdong Provincial Key Laboratory of Magnetoelectric Physics and DevicesSchool of PhysicsSun Yat-sen University

The discovery of superconductivity with Tcabove 77 K in pressurized La3Ni2O7has stimulated enormous interest in the field of unconventional superconductivity.A recent experiment in La2PrNi2O7has shown that the superconducting volume is close to100%.Because the superconductivity can only be achieved under high pressures,many intrinsic properties,such as the superconducting gaps,have not been measured *** report the Andreev reflection measurement of pressurized La3Ni2O7with the onset superconducting transition temperature at about 77 *** data reveal a clear peak of differential conductivity near zero bias in the tunneling spectrum;and appear also are some temperature-dependent steps that may reflect other superconducting *** based on the Blonder-Tinkham-Klapwijk model with multiple components can roughly fit the data,and the central peak can be fitted with a d-wave gap with a magnitude of about 9 meV,and other two s-wave gaps at about 16 and 26 *** latter two large gaps are determined from the enhanced steps of the differential conductivity,which may have other *** results reveal possible evidence of a sign-reversal gap and multi-component features of the superconducting gaps in the nickelate 327 systems.

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Computed tomography enterography-based radiomics for assessing mucosal healing in patients with small bowel Crohn's disease

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World Journal of Gastroenterology 2025年第3期31卷 62-72页

作者： Hao Ding Yuan-Yuan Fang wen-Jie Fan Chen-Yu Zhang Shao-Fei Wang Jing hu Wei Han Qiao Mei Department of Gastroenterology The First Affiliated Hospital of Anhui Medical UniversityHefei 230022Anhui ProvinceChina Department of Radiation Oncology The First Affiliated Hospital of Anhui Medical UniversityHefei 230022Anhui ProvinceChina Department of Gastroenterology Suzhou First People's HospitalSuzhou 234099Anhui ProvinceChina

BACKGROUND Mucosal healing(MH)is the major therapeutic target for Crohn's disease(CD).As the most commonly involved intestinal segment,small bowel(SB)assessment is crucial for CD ***,it poses a significant challenge due to its limited accessibility through conventional endoscopic *** To establish a noninvasive radiomic model based on computed tomography enterography(CTE)for MH assessment in SBCD *** Seventy-three patients diagnosed with SBCD were included and divided into a training cohort(n=55)and a test cohort(n=18).Radiomic features were obtained from CTE images to establish a radiomic *** demographics were analysed to establish a clinical model.A radiomic-clinical nomogram was constructed by combining significant clinical and radiomic *** diagnostic efficacy and clinical benefit were evaluated via receiver operating characteristic(ROC)curve analysis and decision curve analysis(DCA),*** Of the 73 patients enrolled,25 patients achieved *** radiomic-clinical nomogram had an area under the ROC curve of 0.961(95%confidence interval:0.886-1.000)in the training cohort and 0.958(0.877-1.000)in the test cohort and provided superior clinical benefit to either the clinical or radiomic models alone,as demonstrated by *** These results indicate that the CTE-based radiomic-clinical nomogram is a promising imaging biomarker for MH and serves as a potential noninvasive alternative to enteroscopy for MH assessment in SBCD patients.

关键词： Crohn’s disease Computed tomography enterography Mucosal healing Nomogram Radiomics

浙闽地区下白垩统黑色泥岩沉积环境初探:微体古生物与有机地球化学证据

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沉积学报 2010年第6期28卷 1108-1116页

作者：谢小敏胡文瑄曹剑姚素平边立曾高玉巧中国石油化工股份有限公司无锡石油地质研究所江苏无锡214151 南京大学地球科学系南京210093

在中国东南沿海浙闽地区的中生代火山岩分布区,广泛发育有中生代沉积岩系,关于这套沉积岩是否受到海水作用影响,目前还存在争论。通过对福建下白垩统坂头组(K1b)、浙江地区为寿昌组(K1s)和馆头组(K1g)地层进行系统观察及采样,并进行详... 详细信息

在中国东南沿海浙闽地区的中生代火山岩分布区,广泛发育有中生代沉积岩系,关于这套沉积岩是否受到海水作用影响,目前还存在争论。通过对福建下白垩统坂头组(K1b)、浙江地区为寿昌组(K1s)和馆头组(K1g)地层进行系统观察及采样,并进行详细的古生物化石观察及有机地球化学研究,发现该区沉积岩中除陆相高等植物之外,还见过渡相的线叶植物和海相红藻和褐藻化石;同时某些有机地球化学特征亦显示其具有一定的海相沉积特征,如普遍存在较高的伽马蜡烷含量,伽马蜡烷/C30藿烷比值较低(0.11～0.18,平均值0.14),以及C30重排藿烷检出。因此,从古生物学与有机地球化学特征来看,该区的确受到海侵作用影响,结合地质背景,推测海侵事件主要受古太平洋域的影响。

关键词：浙闽地区下白垩统有机地球化学海相化石沉积环境