Subjects: Physics >> Nuclear Physics submitted time 2024-02-28
Xu Hanghua
Liu Longxiang
Zhang Yue
Hao Zirui
Yang Yuxuang
Jin Sheng
Chen Kaijie
Li Zhicai
Jiao Pu
Zhou Mengdie
Wang Zhenwei
Wang Hongwei
Fan Gongtao
Abstract： : Introduces the construction and trial operation of Shanghai Laser Electron Gamma Source (SLEGS) beamline station, one
of the Shanghai light source(SSRF) projects II, which can carry out basic research on nuclear physics and nuclear astrophysics, and
carry out applied research such as gamma irradiation, gamma imaging and gamma activation at SLEGS gamma source. The SLEGS
beamline station passed the process acceptance in December 2021, entered the trial operation stage in October 2022, and have open
to users in September 2023. SLEGS is the first in the world to use the continuous collision angle mode to change the energy of the
gamma beam, with the best energy scanning accuracy, flow intensity density and efficient energy regulation ability. In the trial
operation stage, the SLEGS beamline station focused on solving the problem of online monitoring of gamma beam energy spectrum
and flow intensity, mainly completed the experimental methodology research of optical neutron cross-section measurement by flat
efficiency spectrometer (FED), and carried out the expansion and research of application platforms such as gamma imaging, gamma
activation, and positron source generation. With the development of inverse Compton scattering techniques, short-pulse,
high-polarization, high-throughput, and miniaturized laser Compton scattering light sources will usher in better development
opportunities in the future, and will play an important role in nuclear physics, astrophysics, particle physics, polarization physics, as
well as aerospace, medical testing, energy development and other gamma source application research fields.
Subjects: Physics >> Nuclear Physics submitted time 2024-02-20
Longxiang Liu
Kang Sun
Han Yi
Fei Lu
Hongwei Wang
Gongtao Fan
Xiguang Cao
Yue Zhang
Suyalatu Zhang
Dexin Wang
Xinxiang Li
Yuxuang Yang
Pan Kuang
Xinrong Hu
Zirui Hao
Sheng Jin
Kaijie Chen
Wei Jiang
Ruirui Fan
Qiang Li
Abstract： The angle-differential cross sections of neutron-induced d production from carbon were measured at neutron energies 33.9 MeV at China Spallation Neutron Source (CSNS) Back-n white neutron source. By employing the ΔE-E telescopes of the Light-charged Particle Detector Array (LPDA) system at 24.5° to 155.5° in the laboratory system, the angle-differential cross sections of the 12C(n,d)x reactions were measured.
The experimental results are in good agreement with the previous ones.The present work can provide a reference to the data library considering the lack of experimental data.
Subjects: Physics >> Nuclear Physics submitted time 2024-01-09
J. Hu
Z.Y. Han
Y.J. Li
Z.H. Li
G. Lian
Y.P. Shen
S.Q. Yan
S. Zeng
B. Guo
W.P. Liu
Z. Bai
B.L. Jia
S.L. Jin
J.B. Ma
P. Ma
S.B. Ma
S.W. Xu
Y.Y. Yang
N.T. Zhang
X.D. Tang
Abstract： In Orgueil meteorites, an exceptionally high 22Ne/20Ne abundance ratio or even nearly pure 22Ne is ob#2;served, which is the so-called Ne extraordinary problem. Fossil material of extinct 22Na is believed to be the origin of extraordinary 22Ne, these 22Na nuclides were trapped in grains and incorporated into meteorites in stellar explo#2;sive event. Supernovae and neon-rich novae are the primary events, which are responsible for the production of 22Na through the explosive hydrogen burning process. 22Na(p, γ)23Mg and 19Ne(α, p) 22Na are two crucial reactions in the so-called NeNa-MgAl cycle and the rapid-proton process, which lead to the fast nucleosynthesis up to A=100 nuclide region and the outburst of novae and X-ray bursters. Since many proton resonance levels in odd-A compound nucleus 23Mg may be involved at nova temperature, existing measurements can only provide partial effective information on the 22Na(p, γ)23Mg reaction. Large uncertainties still exist in the astrophysical reaction rates of the two reactions at present. Thick target inverse kinematics method is a very effective way to scan the 23Mg proton resonance levels re#2;lated to the 22Na(p, γ)23Mg reaction via the excitation function of 22Na(p, p) elastic scattering, which could be obtained over a large energy range in one-shot measurement with low-intensity radioactive 22Na beam. In the present work, 22Na+p resonance scattering via thick target inverse kinematics was studied at RIBLL1 radioactive beam line in the HIRFL national laboratory at Lanzhou. A high-purity 22Na beam with an intensity of about 2 × 105 pps was produced via the 1H(22Ne,22Na)n reaction with an alcohol-cooled hydrogen gas target. Time-of-Flight by two plastic scintillator detectors and two parallel-plate avalanche counters were used to monitor the 22Na secondary beam before reaching the (CH2 )n target. The timing information is useful for beam particle identification and the position information is essen#2;tial for 22Na(p,p) elastic scattering kinematics reconstruction. Light recoil particles from 22Na+p reaction system were detected by two sets of double-sided silicon strip detector telescopes centered at 𝜃lab = 0° and 14°, respectively, while the heavy recoil particles were stopped in the (CH2 )n thick target. Two-body kinematics reconstruction of 22Na(p,p) elastic scattering is performed on the event-by-event basis, and an excitation function of 22Na(p,p) is obtained in the energy range of 𝐸c.m. = 1.5 to 4 MeV. Obvious proton resonance structure is observed in the 23Mg compound nucleus, which will be further analyzed with R-matrix nuclear theoretical model.
Subjects: Physics >> Nuclear Physics submitted time 2023-11-08
Hui-Ling Wei
Meng-Die Zhou
Pu Jiao
Yu-Ting Wang
Jie Pu
Kai-Xuan Cheng
Ya-Fei Guo
Chun-Yuan Qiao,
Gong-Tao Fan
Hong-Wei Wang,
Chun-Wang Ma
Abstract： From the empirical phenomena of fragment distributions in nuclear spallation reactions, semiempirical formulas named SPAGINS were constructed to predict fragment crosssections in high-energy γ-induced nuclear spallation reactions (PNSR). In constructing the SPAGINS formulas, theoretical models, including the TALYS toolkit, SPACS, and Rudstam formulas, were employed to study the general phenomenon of fragment distributions in PNSR with incident energies ranging from 100 to 1000 MeV. Considering the primary characteristics of PNSR, the SPAGINS formulas modify the EPAX and SPACS formulas and efficiently reproduce the measured data. The SPAGINS formulas provide a new and effective tool for predicting fragment production in PNSR.
Subjects: Medicine, Pharmacy >> Clinical Medicine submitted time 2023-09-25 Cooperative journals: 《中国全科医学》
Abstract： Background Tiaozhong Yiqi Soup was first used to treat gastrointestinal diseases caused by spleen deficiency and dampness stagnation. Years of experience in treating slow transit constipation（STC） in the elderly through the addition or subtraction of this formula has been found can treat elderly slow transit constipation. Objective To evaluate the clinical effect of Tiaozhong Yiqi Soup on elderly Qi deficiency type STC and intestinal motility. Methods A total of 100 cases of Qi deficiency type STC patients were selected from the Proctology Department and the Prevention and Treatment Center of Traditional Chinese Medicine Hospital of Yinchuan City from May 2022 to April 2023，and randomly divided into the observation group of 50 cases and control group of 50 cases using a 1∶1 randomized numerical table method. The observation group was orally treated with Tiaozhong Yiqi Soup decoction，the control group of 50 patients was orally treated with Prukapril Succinate Tablets， each group was treated for 4 weeks. The score of weekly complete spontaneous bowel movement（CSBM），traditional Chinese medicine（TCM） syndrome score，clinical symptom score，exclusion rates of markers at 48 and 72 hours before and after 4 weeks of treatment were recorded and compared，gastrointestinal hormone levels were detected and the occurrence of adverse reactions was observed. Results After 4 weeks of treatment，the weekly CSBM score，TCM syndrome score，and clinical symptom score of the observation group were lower than those of the control group（P<0.05），and the exclusion rates of markers at 48 and 72 hours were significantly higher than those of the control group（P<0.05）. The serum 5-HT，VIP，and SS of the observation group were lower than those of the control group，while the GAS higher than the control group，with statistical significant difference（P<0.05）. The total clinical effective rate of the observation group was higher than that of the control group after 4 weeks of treatment（χ2 =4.031，P=0.046）. Following up for 3 months，the recurrence rate of the observation group was higher than that of the control group，and the difference was statistically significant（χ2 =5.134，P=0.023）. In the course of the study，2 cases in the observation group developed abdominal distension after taking Zhongzhong Yiqi Soup，while 4 cases in the control group developed dry mouth，nausea，dizziness，and other symptoms after taking Prukapril Succinate Tablets orally，all of which were not treated symptomatically，and the symptoms disappeared on their own after the termination of the trial. Conclusion Self formulated Tiaozhong Yiqi Soup can improve TCM syndrome，weekly CSBM，and clinical symptoms in elderly STC patients，regulate gastrointestinal neurohormone levels，promote gastrointestinal motility，with a low clinical recurrence rate，which is worthy of clinical promotion.
Subjects: Medicine, Pharmacy >> Clinical Medicine submitted time 2023-06-08 Cooperative journals: 《中国全科医学》
Abstract： Background The intestinal flora and its metabolites play an important role in the pathology of chronic heart failure（CHF），which is a severe manifestation or terminal stage of various cardiovascular diseases. Increasing evidence has shown that dysbiosis of the intestinal flora and its metabolites can lead to bacterial translocation，release of mediators，inflammatory response and consequently aggravation of CHF. Objective To analyze the changes of intestinal flora and its metabolite phenylacetylglutamine （PAGln） in patients with CHF and explore the role played by gut microbiota in heart failure. Methods A total of58 patients with heart failure admitted to the Department of Cardiology of the South Branch of the Sixth People's Hospital of Shanghai Jiaotong University were selected as the CHF group，and 46 patients with the same CHF risk factors but without clinical symptoms and past medical history of CHF were selected as the control group. The abundance and diversity of intestinal flora in the two groups were analyzed using 16S rRNA sequencing. Liquid chromatography with tandem mass spectrometry （LC-MS/MS） was used to detect PAGln concentrations in the plasma of samples from both two groups. Results The left ventricular end-systolic diameter （LVESD），left ventricular end-diastolic diameter （LVEDD），brain natriuretic peptide （BNP），and PAGln in the CHF group were higher than the control group，and the left ventricular ejection fraction （LVEF） was lower than the control group （P<0.05）. The area under curve （AUC） of BNP and PAGln levels for the diagnosisof CHF patients was 0.995 and 0.913，respectively. Venn diagram showed that the number of OTUs specific to the CHF group was less than the control group. Alpha diversity analysis showed that the Chao 1 index was lower in the CHF group than the control group （P<0.05）. β diversity analysis showed that the overall structure of the intestinal flora differed between the two groups. At the genus level，the relative abundances of Escherichia-Shigella，Megamonas，Klebsiella，Bifidobacterium，Parabacteroides，and Romboutsia were higher in the CHF group than the control group （P<0.05），and the relative abundances of Solimonas and Dorea were lower than the control group （P<0.05）. The results of LEfSe analysis showed that Lachnospiraceae，Solimonadaceae，Solimonas，Dorea，and Burkholderiaceae were elevated in the control group （P<0.05），and Enterobacteriaceae，Escherichia Bifidobacterium，Bifidobacteriaceae，Klebsiella，Lactobacillaceae，Lactobacillus，Megamonas，Rikenellaceae，Alistipes，Parabacteroides，and Tannerellaceae were elevated in the CHF group （P<0.05）. Typical correlation analysis （CCA） showed that BNP，PAGln，LVEDD，and LVESD were significantly correlated with the CHF group，with BNP having the greatest effect on community changes. Correlation analysis showed that Escherichia-Shigella was positively correlated with BNP and PAGln；Bacteroides was negatively correlated with BNP；Romboutsia，Fusobacterium，and Phascolarctobacterium were negatively correlated with BNP and PAGln. Conclusion The structural composition of the intestinal flora in patients with CHF was significantly different from the patients with the same co-morbidities but without clinical manifestations and previous medical history of CHF，with a decrease in flora diversity and a significant increase in the abundance of pathogenic intestinal bacteria，which may lead to an increase in the level of PAGln in CHF patients and participate in the development of CHF.
Subjects: Other Disciplines >> Synthetic discipline submitted time 2023-05-08 Cooperative journals: 《中国科学院院刊》
Abstract： In recent years, the United States has seriously hindered the development of science and technology in China by implementing a series of measures such as export controls, economic sanctions, and cooperation restrictions, and United States-China technological frictions have brought a series of major problems related to technological and economic security to Chinese industries and enterprises. Based on the existing research, the study analyzes the current situation of China’s science and technology security, the impact of technological friction on enterprises of China and the United States as well as enterprises of other countries, and puts forward policy recommendations in terms of building a science and technology risk monitoring and early warning mechanism, strengthening the ability of original innovation and strategic technology research, promoting high-quality upgrading of industrial value chain, cultivating forging long-board enterprise subjects and clusters, improving the training and introduction mechanism of scientific and technological talents, actively expanding international cooperation, etc.
Subjects: Physics >> Nuclear Physics submitted time 2022-06-13
Abstract：Shanghai Laser Electron Gamma Source (SLEGS) is a powerful gamma source to provide MeV gamma-ray beams for nuclear science and technology. It is developed as one of the sixteenbeamline stations in Phase II Project of the Shanghai Synchrotron Radiation Facility (SSRF). Theslant-scattering mode is for the first time systematically employed in the laser Compton scattering (LCS) at SLEGS to produce energy-tunable quasi-monoenergetic gamma-ray beams. SLEGS officially completed its commissioning from July to December 2021. Gamma-rays in energy range of 0.25 - 21.7 MeV with the flux of 2.1 104 - 1.2 107 photons/s and the energy spread of 2 15 % are produced during the test. This paper reports results of the commissioning of the SLEGS beamline.
Peer Review Status:
Awaiting Review
Subjects: Agriculture, Forestry,Livestock & Aquatic Products Science >> Basic Disciplines of Agriculture submitted time 2017-11-10 Cooperative journals: 《中国生态农业学报》
Abstract：为明确硫肥用量在作物增产方面的效应, 本研究采用单因素随机区组设计, 通过大田试验, 设置5 个硫肥(硫磺)用量, 分别为0 kg(S)·hm2(S0)、40 kg(S)·hm2(S1)、80 kg(S)·hm2(S2)、120 kg(S)·hm2(S3)和160kg(S)·hm2(S4), 研究不同硫肥用量对玉米产量和氮硫素吸收、分配的影响。结果表明, 施用硫肥可使玉米产量增加7.0%~18.1%, S2 处理玉米产量最高, 为12 978.30 kg·hm2。施用硫肥能显著提高玉米各生育时期(除大喇叭口期外)植株干物质积累量。成熟期, 玉米叶片、叶鞘、籽粒干物质积累量均在S2 处理下达最大值, 玉米茎秆、苞叶、穗轴干物质积累量均在S1 处理下达最大值。整个生育期内, 玉米硫素积累量和硫素吸收强度均在S2 处理下达最大值, 且显著高于不施硫的S0 处理。成熟期时, 玉米叶片硫素积累量随施硫量的增加而增加,S4 处理时达最大值; 玉米茎秆、苞叶、穗轴硫素积累量均在S1 处理下最大; 玉米叶鞘和籽粒硫素积累量则S2处理下最大。从拔节期至抽雄吐丝期, S3 处理促进玉米氮素积累效果最佳; 灌浆期和成熟期分别以S1 和S2 处理更有助于玉米氮素积累。施硫量的增加会在一定程度上降低玉米硫肥偏生产力和硫肥利用率; 玉米硫肥农学利用率在S2 处理下最大。玉米植株的氮素和硫素吸收累积量具有极显著相关关系。因此, 适量的硫肥在提高玉米产量和氮硫吸收、分配及利用效率方面发挥着重要作用, 施硫量为80 kg(S)·hm2 时, 整体效果最佳。
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