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Substituent effect on the molecular stability,group interaction,detonation performance,and thermolysis mechanism of nitroamino-substituted cyclopentanes and cyclohexanes

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Science China Chemistry 2008年第12期51卷 1231-1245页

作者： qiu Ling GONG XueDong ju XueHai XIAO HeMing Institute for Computation in Molecular and Material Science School of Chemical EngineeringNanjing University of Science and TechnologyNanjing 210094China Key Laboratory of Nuclear Medicine Ministry of HealthJiangsu Institute of Nuclear MedicineWuxi 214063China

Density functional theory (DFT) method has been employed to study the effect of nitroamino group as a substituent in cyclopentane and cyclohexane, which usually construct the polycyclic or caged nitra-mines. Molecular structures were investigated at the B3LYP/6-31G** level, and isodesmic reactions were designed for calculating the group interactions. The results show that the group interactions ac-cord with the group additivity, increasing with the increasing number of nitroamino groups. The dis-tance between substituents influences the interactions. Detonation performances were evaluated by the Kamlet-Jacobs equations based on the predicted densities and heats of formation, while thermal stability and pyrolysis mechanism were studied by the computations of bond dissociation energy (BDE). It is found that the contributions of nitroamino groups to the detonation heat, detonation velocity, detonation pressure, and stability all deviate from the group additivity. Only 3a, 3b, and 9a-9c may be novel potential candidates of high energy density materials (HEDMs) according to the quantitative cri-teria of HEDM (ρ≈ 1.9 g/cm3, D ≈ 9.0 km/s, P ≈ 40.0 GPa). Stability decreases with the increasing number of N-NO2 groups, and homolysis of N-NO2 bond is the initial step in the thermolysis of the title com-pounds. Coupled with the demand of thermal stability (BDE > 20 kcal/mol), only 1,2,4-trinitrotriazacy-clohexane and 1,2,4,5-tetranitrotetraazacyclohexane are suggested as feasible energetic materials. These results may provide basic information for the molecular design of HEDMs.

关键词： density functional theory (DFT) substituent effect monocyclic nitramine high energy density material (HEDM) group interaction detonation performance thermal stability bond dissociation energy (BDE)

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Does the Amati Relation depend on the Luminosity of the GRB's Host Galaxy?

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Chinese Journal of Astronomy and Astrophysics 2008年第3期8卷 255-261页

作者： Jing Wang Jing-Song deng Yu-Lei qiu National Astronomical Observatories Chinese Academy of Sciences Beijing 100012 China

In order to test the systematics of the Amati relation, 24 long-duration GRBs with available Eγ,iso and Ep are separated into two subgroups according to the B-band luminosity of their host galaxies. The Amati relations in the two subgroups are found to be in agreement with each other within the uncertainties. Taking into account of the well established luminosity - metallicity relation of galaxies, no strong evolution of the Amati relation with the GRB＇s environmental metaUicity is implied in this study.

关键词： gamma-rays bursts -- gamma-rays observations -- galaxies evolution

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Effect of matrix structure on mechanical properties and dry rolling-sliding wear performance of alloyed ductile iron

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Journal of Iron and Steel Research International 2019年第8期26卷 888-897页

作者： Hua Zhang Yan-xin Wu qiu-ju Li Xin Hong State Key Laboratory of Advanced Special Steel and Shanghai Key Laboratory of Advanced Ferrometallurgy and School of Materials Science and Engineering Shanghai University Shanghai 200072 China Jiangsu Yonggang Group Co. Ltd. Zhangjiagang 215628 Jiangsu China Institute of Engineering Technology University of Science and Technology Beijing Beijing 100083 China

The influence of matrix structure on mechanical properties and dry rolling-sliding wear performance of alloyed ductile iron was examined. Four kinds of alloyed ductile irons with different matrix structures were produced through an adequate balance of alloying elements. Tensile tests and dry rolling-sliding wear tests were carried out at room temperature. The results show that yield strength and ultimate tensile strength increase, while elongation decreases until the matrix fully becomes pearlite. The lower matrix hardness results in more graphite emerging on the contact surface, which yields the decrease in friction coefficient. Besides, the wear rate decreases with the increase in matrix hardness among alloyed ductile irons except that with full pearlite matrix, the wear performance of which seems to be deteriorated due to poor fracture toughness. The main wear mechanism is delamination under an air-cooling condition. Based on the results of mechanical and wear tests, ductile iron with about 80% pearlite exhibits better wear performance as well as relatively reasonable mechanical properties.

关键词： Ductile iron Microstructure Mechanical property Wear Delamination

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内冲击激发式安全雷管的研制与适配性测试

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火工品 2025年第1期 1-6页

作者：邓小娟代鹏举董金龙刘晓娟王爱上海鲲程电子科技有限公司上海201100 广东宏大民爆集团有限公司广东广州510000 湖南湘科控股集团有限公司湖南长沙410000 江西新余国泰特种化工有限责任公司江西新余338000 湖南神斧集团湘南爆破器材有限责任公司湖南永州425000

针对工业雷管在使用过程中因起爆药感度高而引发的安全事故和环境污染问题,研制了一种新型内冲击激发式安全雷管(简称“IID雷管”),并开展其与不同点火药的适配性测试。通过采用猛炸药作为主要装药,以及设计激发组件,实现了高效有序的... 详细信息

针对工业雷管在使用过程中因起爆药感度高而引发的安全事故和环境污染问题,研制了一种新型内冲击激发式安全雷管(简称“IID雷管”),并开展其与不同点火药的适配性测试。通过采用猛炸药作为主要装药,以及设计激发组件,实现了高效有序的起爆和传爆过程;通过与不同点火药的适配测试,以及对起爆能力、延期精度等关键功能的全面评估,验证了IID雷管在与LTNR和K-K等药剂适配时,各项性能均满足行业标准。此外,IID雷管结构工艺简单、安全环保,具有广泛的应用前景。

关键词：安全雷管数码电子雷管内冲击激发无起爆药雷管激发组件

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Poly(amide-6-b-ethylene oxide)/[Bmim][Tf2N] blend membranes for carbon dioxide separation

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Journal of Energy Chemistry 2016年第1期25卷 122-130页

作者： Yongtao qiu Jizhong Ren Dan Zhao Hui Li Maicun deng National Laboratory for Clean Energy Dalian Institute of Chemical Physics Chinese Academy of Sciences Dalian 116023 Liaoning China University of Chinese Academy of Sciences Beijing 100049 China

Poly（amide-6-b-ethylene oxide）（Pebax1657）/1-butyl-3-methylimidazo-lium bis[trifluoromethyl）sulfonyl]-imide（[Bmim][Tf2N]） blend membranes with different [Bmim][Tf2N] contents were prepared via solution casting and solvent evaporation method. The permeation properties of the blend membranes for CO2, N2,CH4 and H2 were studied, and the physical properties were characterized by differential scanning calorimeter（DSC） and X-ray diffraction（XRD）. Results showed that [Bmim][Tf2N] was dispersed as amorphous phase in the blend membranes, which caused the decrease of Tg（PE） and crystallinity（PA）. With the addition of [Bmim][Tf2N], the CO2 permeability increased and reached up to approximately 286 Barrer at 40 wt%[Bmim][Tf2N], which was nearly double that of pristine Pebax1657 membrane. The increase of CO2 permeability may be attributed to high intrinsic permeability of [Bmim][Tf2N], the increase of fractional free of volume（FFV） and plasticization effect. However, the CO2 permeability reduced firstly when the [Bmim][Tf2N]content was below 10 wt%, which may be due to that the small ions of [Bmim][Tf2N] in the gap of polymer chain inhibited the flexibility of polymer chain; the interaction between Pebax1657 and [Bmim][Tf2N]decreased the content of EO units available for CO2 transport and led to a more compact structure. For Pebax1657/[Bmim][Tf2N] blend membranes, the permeabilities of N2, H2 and CH4decreased with the increase of feed pressure due to the hydrostatic pressure effect, while CO2 permeability increased with the increase of feed pressure for that the CO2-induced plasticization effect was stronger than hydrostatic pressure effect.

关键词： Poly(amide-6-b-ethylene oxide) Ionic liquid Carbon dioxide separation Blend membrane

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Improved analysis of the rare decay processes of Λ_(b)

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Communications in Theoretical Physics 2021年第10期73卷 114-124页

作者： Ren-hao deng Yong-lu Liu Ming-qiu Huang College of Art and Science National University of Defense TechnologyHunan 410073China

It is noted that in the new Particle Data Group(PDG) version the rare decays of the Λ_(b) baryon have been revised with more accuracy. The new results show that most of the existing theoretical results on the process Λ_(b)→Λ_(γ) Lgbare larger than those of experiments. With the improved higher-order light-cone distribution amplitudes of the Λ baryon, we reanalyze the process in the framework of light-cone quantum chromodynamics sum rules and the branching ratio is estimated to be Br (Λ_(b)→Λ_(γ))=(7.38-0.39+0.40)×10^(16), which is consistent with the new experimental result. Furthermore, another process Λ_(b)→Λl+l- is also analyzed in the same frame. The final branching ratio is calculated to be Br (Λ_(b)→Λl+l-)=1.20×10^(-6), which is in good accordance with the data from the PDG and other theoretical predictions.

关键词： light-cone distribution amplitude rare decay light-cone QCD sum rules

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Open metallocenes——Ⅺ. A pentadienyl compound of heavier rare earth element [2,4-(CH_3)_2-η~5-C_5H_5]_3Tb·1/2THF

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Chinese Journal of Chemistry 1991年第1期9卷 10-19页

作者： qiu,Xin LIU,ju-Zheng Intitute of Theoretical Chemistry Jilin UniversityChangchun 130023

Perfluoroalkyl iodides reacted with conjugated dienes in aqueous acetonitrile solution in the presence of sodium dithionite at room temperature to give dimerization products, whereas, perfluo- roalkanesulfonyl bromide... 详细信息

关键词： A pentadienyl compound of heavier rare earth element C5H5 CH3 Open metallocenes THF

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Nutri-microbiome epidemiology,an emerging field to disentangle the interplay between nutrition and microbiome for human health

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Protein & Cell 2023年第11期14卷 787-806页

作者： Wanglong Gou Zelei Miao Kui deng ju-Sheng Zheng Westlake Intelligent Biomarker Discovery Lab Westlake Laboratory of Life Sciences and BiomedicineHangzhou 310024China Research Center for Industries of the Future Key Laboratory of Growth Regulation and Translational Research of Zhejiang ProvinceSchool of Life SciencesWestlake UniversityHangzhou 310030China Institute of Basic Medical Sciences Westlake Institute for Advanced StudyHangzhou 310024China

Diet and nutrition have a substantial impact on the human microbiome,and interact with the microbiome,especially gut microbiome,to modulate various diseases and health *** research has also guided the nutrition field to a more integrative direction,becoming an essential component of the rising area of precision *** this review,we provide a broad insight into the interplay among diet,nutrition,microbiome,and microbial metabolites for their roles in the human *** the microbiome epidemiological studies regarding the associations of diet and nutrition with microbiome and its derived metabolites,we summarize those most reliable findings and highlight evidence for the relationships between diet and disease-associated microbiome and its functional ***,the latest advances of the microbiome-based precision nutrition research and multidisciplinary integration are ***,we discuss several outstanding challenges and opportunities in the field of nutri-microbiome epidemiology.

关键词： microbiome nutrition human health epidemiology

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Pharmacological Effects of Botanical Drugs on Myocardial Metabolism in Chronic Heart Failure

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Chinese Journal of Integrative Medicine 2024年第5期30卷 458-467页

作者： HU Yu-xuan qiu Sheng-lei SHANG ju-ju WANG Zi LAI Xiao-lei Beijing Hospital of Traditional Chinese Medicine Capital Medical UniversityBeijing 100010China

Although there have been significant advances in the treatment of heart failure in recent years,chronic heart failure remains a leading cause of cardiovascular disease-related *** studies have found that targeted cardiac metabolic remodeling has good potential for the treatment of heart ***,most of the drugs that increase cardiac energy are still in the theoretical or testing *** research has found that botanical drugs not only increase myocardial energy metabolism through multiple targets but also have the potential to restore the balance of myocardial substrate *** this review,we summarized the mechanisms by which botanical drugs(the active ingredients/formulas/Chinese patent medicines)improve substrate utilization and promote myocardial energy metabolism by activating AMP-activated protein kinase(AMPK),peroxisome proliferator-activated receptors(PPARs)and other related *** the same time,some potential protective effects of botanical drugs on myocardium,such as alleviating oxidative stress and dysbiosis signaling,caused by metabolic disorders,were briefly discussed.

关键词： botanical drugs chronic heart failure myocardial metabolism pharmacological effects review

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Hepatocellular carcinoma: Mechanisms of progression and immunotherapy

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World Journal of Gastroenterology 2019年第25期25卷 3151-3167页

作者： Yu Jiang qiu-ju Han Jian Zhang Institute of Immunopharmaceutical Sciences School of Pharmaceutical SciencesShandong University

Liver cancer is one of the most common malignancies,and various pathogenic factors can lead to its occurrence and *** all primary liver cancers,hepatocellular carcinoma(HCC)is the most *** extensive studies,an increasing number of molecular mechanisms that promote HCC are being *** resection is still the most effective treatment for patients with early ***,early detection and treatment are difficult for most HCC patients,and the postoperative recurrence rate is high,resulting in poor clinical prognosis of *** immunotherapy takes longer than conventional chemotherapy to produce therapeutic effects,it persists for *** recent years,the emergence of many new immunotherapies,such as immune checkpoint blockade and chimeric antigen receptor T cell therapies,has given new hope for the treatment of HCC.

关键词： Hepatocellular carcinoma Mechanisms Immunotherapy

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