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核素的自旋角动量量子数和群子参数间关系

北京化工大学学报（自然科学版） 2000年第3期27卷 24-28页

作者：金日光北京化工大学材料科学与工程学院北京100029

详细考察了核群子结构的参数 (m ,n ,k ,l)与核素角动量量子数之间的关系 ,提出了核素群子模型理论及其四项原则。分别讨论了核素角动量量子数为 1 /2 ,3/2 ,5/2 ,7/2 ,9/2及 0 ,1 ,2 ,3,4,5,6,7,8的情形 ,较圆满地解释了各种核素所具... 详细信息

详细考察了核群子结构的参数 (m ,n ,k ,l)与核素角动量量子数之间的关系 ,提出了核素群子模型理论及其四项原则。分别讨论了核素角动量量子数为 1 /2 ,3/2 ,5/2 ,7/2 ,9/2及 0 ,1 ,2 ,3,4,5,6,7,8的情形 ,较圆满地解释了各种核素所具有的总角动量量子数与核素群子结构之间关系。从中进一步看出单粒子壳层模型理论难以全面地预测核素的总角动量量子数。

关键词：核素角动量量子数核群子参数核素模型

形成原子核群子结构的四项原理及其等腰三角形核素周期律

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北京化工大学学报（自然科学版） 2000年第1期27卷 33-37页

作者：金日光北京化工大学材料科学与工程学院北京100029

根据第四统计力学———JRG群子统计理论,首次提出了形成原子核结构的四项原理及相应的原子核周期律。这四项原理为:一是原子核有群子结构单元;二是形成原子核时群子通过热核聚合反应过程使核素结构有严格的排列顺序;三是原子核内群子... 详细信息

根据第四统计力学———JRG群子统计理论,首次提出了形成原子核结构的四项原理及相应的原子核周期律。这四项原理为:一是原子核有群子结构单元;二是形成原子核时群子通过热核聚合反应过程使核素结构有严格的排列顺序;三是原子核内群子结构间有动态共振作用;四是偶数群子稳定,而非偶数群子是引起总角动量和β+,β-衰变的根源。基于上述四项原理,提出了核群子结构基本单元有(PB),(PB2),(P2B3),并随着质子数Z的增加,核群子结构由(PB)k过渡到(PB)k(P2B3)l;由(PB)n(PB2)m过渡到(P2B3)s(PB2)t。从而导出了k(-t)=2n(s)-Z,k(-t)=Z-2l(m)的关系式。基于此,可以画出等腰三角形原子核群子周期律。还发现,不管A,N,Z如何变化,有下列严格关系式:ZN=n+mn+2m或ZN=k+lk+3l并且Z=n+l。此公式高度地反映了所有原子核内质子和中子分布的整数规律。还可以通过等腰三角形周期律得知:k,l,m,n,s,t均与核素群子(PB),(PB2),(P2B3),(P3B4)的2,3,5,7整数倍有关。

关键词：原子核群子结构等腰三角形核素周期律

Optimizing mechanical properties of HIPS fabricated with low-cost desktop 3D printers:investigating the impact of process parameters

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Advances in Manufacturing 2024年第2期12卷 379-395页

作者： jin-Ting Xu guang-Wei Zhang Man-Man Chen School of Automotive Engineering Dalian University of TechnologyDalian116024People’s Republic of China

Recently,low-cost desktop three-dimensional(3D)printers,employing the fused deposition modeling(FDM)technique,have gained widespread ***,most users cannot test the strength of printed parts,and little information is available about the mechanical properties of printed high-impact polystyrene(HIPS)parts using desktop 3D *** this study,the user-adjustable parameters of desktop 3D printers,such as crisscross raster orientation,layer thickness,and infill density,were *** experimental plans were designed using the Box-Behnken method,and tensile,3-point bending,and compression tests were carried out to determine the mechanical responses of the printed *** prediction models of the process parameters were regressed to produce the optimal combination of process *** experimental results showcase that the crisscross raster orientation has significant effects on the flexural and compression strengths,but not on the tensile *** an increase in the layer thickness,the tensile,flexural,and compression strengths first decreased and then increased,reaching their minimum values at approximately 0.16 mm layer *** addition,they all increased with an increase of infill *** was demonstrated that when the raster orientation,layer thickness,and infill density were 13.08°/–76.92°,0.09 mm,and 80%,respectively,the comprehensive mechanical properties of the printed HIPS were *** results can help end-users of desktop 3D printers understand the effects of process parameters on the mechanical properties,and offer practical suggestions for setting proper printing parameters for fabricating HIPS parts.

关键词： Desktop three-dimensional(3D)printers Fused deposition modeling(FDM) High-impact polystyrene(HIPS) Process parameters

Electromagnetic fields in ultra-peripheral relativistic heavy-ion collisions

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Nuclear Science and Techniques 2024年第2期35卷 103-109页

作者： Jie Zhao jin-Hui Chen Xu-guang Huang Yu-Gang Ma Key Laboratory of Nuclear Physics and Ion-beam Application(MOE) Institute of Modern PhysicsFudan UniversityShanghai 200433China Shanghai Research Center for Theoretical Nuclear Physics NSFC and Fudan UniversityShanghai 200438China Physics Department and Center for Particle Physics and Field Theory Fudan UniversityShanghai 200438China

Ultra-peripheral heavy-ion collisions(UPCs)offer unique opportunities to study processes under strong electromagnetic *** these collisions,highly charged fast-moving ions carry strong electromagnetic fields that can be effectively treated as photon *** exchange of photons can induce photonuclear and two-photon interactions and excite *** excitation of the ions results in Coulomb dissociation with the emission of photons,neutrons,and other ***,the electromagnetic fields generated by the ions can be sufficiently strong to enforce mutual interactions between the two colliding ***,the two colliding ions experience an electromagnetic force that pushes them in opposite directions,causing a back-to-back correlation in the emitted *** a Monte Carlo simulation,we qualitatively demonstrate that the above electromagnetic effect is large enough to be observed in UPCs,which would provide a clear means to study strong electromagnetic fields and their effects.

关键词： Electromagnetic fields Neutrons Ultra-peripheral relativistic heavy-ion collisions(UPC)

Experimental investigation on using CO_(2)/H_(2)O emulsion with high water cut in enhanced oil recovery

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Petroleum Science 2024年第2期21卷 974-986页

作者： Xi-Dao Wu Peng Xiao Bei Liu guang-jin Chen Jian-Hua Pang State Key Laboratory of Heavy Oil Processing China University of PetroleumBeijing102249China Ocean Intelligence Technology Center Shenzhen Institute of Guangdong Ocean UniversityShenzhen518120GuangdongChina

CO_(2) emulsions used for EOR have received a lot of interest because of its good performance on CO_(2)mobility ***,most of them have been focusing on the high quality CO_(2) emulsion(high CO_(2) fraction),while CO_(2) emulsion with high water cut has been rarely *** this paper,we carried out a comprehensive experimental study of using high water cut CO_(2)/H_(2)O emulsion for enhancing oil ***,a nonionic surfactant,alkyl glycosides(APG),was selected to stabilize CO_(2)/H_(2)O emulsion,and the corresponding morphology and stability were evaluated with a transparent PVT ***,plugging capacity and apparent viscosity of CO_(2)/H_(2)O emulsion were measured systematically by a sand pack displacement apparatus connected with a 1.95-m long capillary ***,a high water cut(40 vol%) CO_(2)/H_(2)O emulsion was selected for flooding experiments in a long sand pack and a core sample,and the oil recovery,the rate of oil recovery,and the pressure gradients were *** results indicated that APG had a good performance on emulsifying and stabilizing CO_(2) *** inversion from H_(2)O/CO_(2) emulsion to CO_(2)/H_(2)O emulsion with the increase in water cut was ***_(2)/H_(2)O emulsions with lower water cuts presented higher apparent viscosity,while the optimal plugging capacity of CO_(2)/H_(2)O emulsion occurred at a certain water ***,the displacement using CO_(2)/H_(2)O emulsion provided 18.98% and 13.36% additional oil recovery than that using pure CO_(2) in long sand pack and core tests,*** work may provide guidelines for EOR using CO_(2) emulsions with high water cut.

关键词： CO_(2)/H_(2)O emulsion High water cut CO_(2) mobility control Enhanced oil recovery

Studies　on　the　Mechanism　of　the　Direct　Synthesis　of　Styrene　form　Benzene　and　Ethylene

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Chemical Research in Chinese Universities 1997年第3期13卷 244-248页

作者： ZHANG Qiang , jin ri-guang (College of Mater, Sci, and Tech, Beijing Univ, of Them, Beijing,100029) YANG Jun (Dept. of Phys, Chem, Shenyang Pharmaceutical Univ., Shenyang,110015)

The adsorption behavior and description behavior of benzene , ethylene and ethylbenzene over HZSM-5 and Co/HZSM-5 catalysts were studied by means of TPSR (Temperature programmed surface reaction) technique. TPSR results of ben- zene and ethylene co-adsorption show that the maian products are styrene , ethylben- zene, toluene, propane, and butane. In a separate experiment of ethylbenzene ad- sorption, styrene . toluene and benzene are formed due to cracking and dehydro- genation. The mechanism of styrene formation was proposed , i. e. , the reaction was carried out via. the dehydrogenation of mediate species ethylbenzene according to the results of TPSR-MS , activity testing and thermodynamic analysis.

关键词： Direct synthesis TPSR-MS Styrene Benzene Ethylene

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桑黄多糖对肥大细胞脱颗粒的机制

中国医院药学杂志 2011年第18期31卷 1532-1534页

作者：洪海金光日金光玉延光海延边中医医院药剂科延边大学附属医院药剂科延边大学医学部解剖学教研部

目的:观察桑黄多糖的抗过敏作用并探讨其可能的作用机制。方法:通过IgE诱导大鼠被动皮肤过敏反应(PCA)实验,用比色法测定桑黄多糖在体内对肥大细胞影响。体外实验观察桑黄多糖对IgE诱导组胺释放、细胞内钙摄入及其他炎性介子的影响。结... 详细信息

目的:观察桑黄多糖的抗过敏作用并探讨其可能的作用机制。方法:通过IgE诱导大鼠被动皮肤过敏反应(PCA)实验,用比色法测定桑黄多糖在体内对肥大细胞影响。体外实验观察桑黄多糖对IgE诱导组胺释放、细胞内钙摄入及其他炎性介子的影响。结果:桑黄多糖明显抑制了肥大细胞脱颗粒、组胺的释放、细胞内钙摄入以及肿瘤坏死因子-α、白细胞介素6的释放(P<0.05)。结论:桑黄多糖抗过敏作用与抑制肥大细胞脱颗粒及炎性介子的释放有关。

关键词：肥大细胞桑黄多糖免疫球蛋白E 组胺钙

Static recrystallization behaviors and mechanisms of 7Mo super-austenitic stainless steel with undissolved sigma precipitates during double-stage hot deformation

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Journal of Iron and Steel Research International 2024年第2期31卷 475-487页

作者： Shi-guang Xu jin-shan He Run-ze Zhang Fu-cheng Zhang Xi-tao Wang Collaborative Innovation Center of Steel Technology University of Science and Technology BeijingBeijing100083China State Key Laboratory of Metastable Materials Science and Technology Yanshan UniversityQinhuangdao066004HebeiChina Shandong Provincial Key Laboratory for High Strength Lightweight Metallic Materials Advanced Materials InstituteQilu University of Technology(Shandong Academy of Science)Jinan250353ShandongChina

Static recrystallization(SRX)behaviors and corresponding recrystallization mechanisms of 7Mo super-austenitic stainless steel were studied under different deformation *** order of influence of deformation parameters on static recrystallization behaviors,from high to low,is followed by temperature,first-stage strain and strain ***,the effect of holding time on static recrystallization behaviors is significantly controlled by *** addition,with the increase in temperature from 1000 to 1200°C,the static recrystallization mechanism evolves from discontinuous static recrystallization and continuous static recrystallization(cSRX)to metadynamic recrystallization and cSRX,and finally to *** cSRX exists at all *** is because high stacking fault energy(56 mJ m−2)promotes the movement of dislocations,making the deformation mechanism of this steel is dominated by planar slip of *** undissolved sigma precipitates promote static recrystallization through particle-stimulated ***,small strain-induced precipitates at grain boundaries hinder the nucleation of conventional SRX and the growth of recrystallized grains,while the hindering effect decreases with the increase in temperature.

关键词： 7Mo super-austenitic stainless steel Double-stage hot deformation Conventional static recrystallization Metadynamic recrystallization Strain-induced precipitation

Recent development of three-dimension printed graphene oxide and MXene-based energy storage devices

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Tungsten 2024年第1期6卷 196-211页

作者： Liang-Hao Yu Xin Tao Shang-Ru Feng jin-Tao Liu Lin-Lin Zhang guang-Zhen Zhao guang Zhu Key Laboratory of Spin Electron and Nanomaterials of Anhui Higher Education Institutes Suzhou UniversitySuzhou 234000China Key Laboratory of Leather of Zhejiang Province College of Chemistry and Materials EngineeringWenzhou UniversityWenzhou 325035China

The research for three-dimension(3D)printing carbon and carbide energy storage devices has attracted widespread exploration *** designable in structure and materials,graphene oxide(GO)and MXene accompanied with a direct ink writing exhibit a promising prospect for constructing high areal and volume energy density *** review not only summarizes the recent advances in 3D printing energy storage devices including printing methods,ink rheological properties,and different energy storage systems,but also discusses the printing methods related to energy *** addition,the binder or additive free of two-dimensional carbide materials is quite important for the present electrochemical energy storage devices,which also are presented.

关键词： 3D printing Two-dimensional materials Energy storage device Ink theological MXene