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1.
The emergence and evolution of worldviews is a complex phenomenon that requires strong and rigorous scientific attention in our hyperconnected world. On the one hand, cognitive theories have proposed reasonable frameworks but have not reached general modeling frameworks where predictions can be tested. On the other hand, machine-learning-based applications perform extremely well at predicting outcomes of worldviews, but they rely on a set of optimized weights in a neural network that does not comply to a well-founded cognitive framework. In this article, we propose a formal approach used to investigate the establishment of and change in worldviews by recalling that the realm of ideas, where opinions, perspectives and worldviews are shaped, resemble, in many ways, a metabolic system. We propose a general modelization of worldviews based on reaction networks, and a specific starting model based on species representing belief attitudes and species representing belief change triggers. These two kinds of species combine and modify their structures through the reactions. We show that chemical organization theory combined with dynamical simulations can illustrate various interesting features of how worldviews emerge, are maintained and change. In particular, worldviews correspond to chemical organizations, meaning closed and self-producing structures, which are generally maintained by feedback loops occurring within the beliefs and triggers in the organization. We also show how, by inducing the external input of belief change triggers, it is possible to change from one worldview to another, in an irreversible way. We illustrate our approach with a simple example reflecting the formation of an opinion and a belief attitude about a theme, and, next, show a more complex scenario containing opinions and belief attitudes about two possible themes.  相似文献   

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3.
基于Mavromoustakos等人的分子动力学和蒙特卡罗方法结果,本文利用量子化学计算的方法研究了SARTANS(沙坦)类的3种AT1受体拮抗剂(V8、V12和BZI8).在B3LYP/6-31G(d)方法下计算得到了3种药物分子的平衡几何结构,并且采用B3LYP-GIAO/6-311G(d,p)方法计算了这些药物分子中的质子化学位移.通过研究结果可以看出,本文采用量子化学方法计算得到的3种分子的结构与Mavromoustakos等人通过分子动力学和蒙特卡罗方法得到的结果比较接近,计算结果与核磁共振实验的ROE数据和1H谱相比吻合得较好,说明所获得的结构较为合理.另外通过对所获得分子结构进行叠合分析发现,同属SARTANS类的3种分子在联苯咪唑环区域具有很大的相似性.  相似文献   

4.
基于Mavromoustakos等人的分子动力学和蒙特卡罗方法结果,本文利用量子化学计算的方法研究了SARTANS(沙坦)类的3种AT1受体拮抗剂(V8、V12和BZI8). 在B3LYP/6-31G(d)方法下计算得到了3种药物分子的平衡几何结构,并且采用B3LYP-GIAO/6-311G(d,p)方法计算了这些药物分子中的质子化学位移. 通过研究结果可以看出,本文采用量子化学方法计算得到的3种分子的结构与Mavromoustakos等人通过分子动力学和蒙特卡罗方法得到的结果比较接近,计算结果与核磁共振实验的ROE数据和1H谱相比吻合得较好,说明所获得的结构较为合理. 另外通过对所获得分子结构进行叠合分析发现,同属SARTANS类的3种分子在联苯咪唑环区域具有很大的相似性.  相似文献   

5.
近年来,随着计算化学理论的不断突破,以及计算硬件性能的大幅提高,基于第一性原理针对有机分子开展1H和13C核磁共振化学位移的精确计算技术也取得了很大进展,部分方法已经逐步用于较大分子及较复杂分子体系的准确预测.本文建立了一个基于密度泛函理论的高精度有机分子化学位移在线计算系统平台,能够在线交互式完成分子量小于800的分子的化学位移计算服务.该系统平台工具能加快构建分子结构与核磁共振谱图的映射关系过程,为有机分子核磁共振谱图的高效指认,以及结构精确解析提供一个新的有力支撑.  相似文献   

6.
Summary The possibility of hydrogen bonding between the nucleic-acid bases and methyl glyoxal or formamide is studied through an IEH calculation; the charge transfer and hydrogen bond indices support this hypothesis. The CH...Y indices are similar to those of usual hydrogen bonds. In six of the nine configurations previously proposed by other authors in order to analyse the H2S-formamide interactions, formamide is predicted to be an electron acceptor.
Riassunto In un calcolo IEH, si studia la possibilità del legame a idrogeno fra le basi costituenti gli acidi nucleici ed il metilgliossale o la formamide, il trasferimento di carica e gl'indici del legame a idrogeno sembrano confermare l'ipotesi. Gl'indici CH...Y sono simili a quelli dei legami a idrogeno usuali. In sei delle nove configurazioni, proposte da altri autori per analizzare l'interazione fra il solfuro d'idrogeno e la formamide, questa risulta essere un accettore di elettroni.

Резюме Используя вычисления IEH, исследуется возможность водородной связи между основаниями нуклеиновых кислот и глиоксалом метила или формамидом. Перенос заряда и индексы водородной связи подтверждают зту гипотезу. Индексы CH...Y являются аналогичными для обычных водородных связей. В шести из девяти конфигураций, ранее предложенных другими авторами для анализа взаимодействий ?H2S-формамид?, предсказывается, что формамид является акцептором злектронов.
  相似文献   

7.
研究了相对论重离子碰撞中产生的共振物质的统计性质,讨论了共振粒子的化学势和净粒子密度的关系. 计算了总粒子密度和能量密度,研究和分析了他们和净粒子密度的关系,并估算了总粒子密度相对于正常核密度(0.16fm-3)的倍数;在RHIC能量约为5-8倍,在SPS能量约为3-6倍. 还研究了各种粒子成分随温度的变化,揭示出几个温度区间段对应AGS、SPS和RHIC三个能区,各区间中主要粒子成分分别为重子、奇异子和介子.  相似文献   

8.
Within the framework of finite temperature field theory this paper discusses the shear viscosity of hot QED plasma through Kubo formula at one-loop skeleton diagram level with a finite chemical potential. The effective widths (damping rates) are introduced to regulate the pinch singularities and then gives a reliable estimation of the shear viscous coefficient. The finite chemical potential contributes positively compared to the pure temperature case. The result agrees with that from the kinetics theory qualitatively.  相似文献   

9.
陆展鹏  魏兴波  刘天帅  陈阿海  高先龙 《物理学报》2017,66(12):126701-126701
通过数值方法求解了有限温度下一维均匀Hubbard模型的热力学Bethe-ansatz方程组,得到了在给定温度和相互作用强度情况下,比热c、磁化率χ和压缩比κ随化学势μ的变化图像.基于有限温度下一维均匀Hubbard模型的精确解,利用化学势(μ)-泛函理论研究了一维谐振势下的非均匀Hubbard模型,给出了金属态和Mott绝缘态下不同温度情况时局域粒子密度n_i和局域压缩比_κi随格点的变化情况.  相似文献   

10.
Within the framework of finite temperature field theory this paper discusses the shear viscosity of hot QED plasma through Kubo formula at one-loop skeleton diagram level with a finite chemical potential. The effective widths (damping rates) are introduced to regulate the pinch singularities and then gives a reliable estimation of the shear viscous coefficient. The finite chemical potential contributes positively compared to the pure temperature case. The result agrees with that from the kinetics theory qualitatively.  相似文献   

11.
提出了一种液氧煤油发动机尾焰红外辐射特性计算方法,首先采用计算流体力学软件对液氧煤油发动机内流场进行计算,然后以获得喷管喉部截面参数作为入口边界条件计算发动机尾焰流场,最后以发动机尾焰流场参数分布为基础,采用有限体积法对发动机尾焰红外光谱辐射特性和成像特性进行计算,并对比验证了模型和方法的准确性。在此基础上,研究了化学反应机理和复燃反应过程对尾焰红外辐射特性影响。结果表明,采用多步化学反应能够准确模拟液氧煤油发动机内流场,温度相比热力学计算大3.34%,压力相比试车测量大2.89%;考虑复燃反应使尾焰红外辐射强度增强显著,在采用单步化学反应和多步化学反应两种工况下2~5波段红外辐射强度分别增大50%~100%和150%~170%,但不会影响尾焰红外光谱辐射特性和红外总辐射强度随探测角变化趋势;采用单步化学反应和多步化学反应都能够获得清晰结构的红外成像图像,但是前者2~5尾焰红外辐射强度要比后者增大90%~190%,且两种工况下发动机尾焰红外光谱辐射特性差别很大,尾焰红外总辐射强度随探测角变化趋势也不同。  相似文献   

12.
Probir Roy 《Pramana》2003,60(2):169-181
We provide a bird’s eyeview of current ideas on supersymmetry breaking mechanisms in the MSSM. The essentials of gauge, gravity, anomaly and gaugino/higgsino mediation mechanisms are covered briefly and the phenomenology of the associated models is touched upon. A few statement are also made on braneworld supersymmetry breaking.  相似文献   

13.
药物小分子化学位移的量子化学计算研究   总被引:2,自引:1,他引:2  
核磁共振的谱峰归属对分子结构的确定至关重要,用理论计算方法预测化学位移对谱峰的正确归属是极其有帮助的. 我们用量子化学的方法预测了乙酰水杨酸及其衍生物分子上碳原子的化学位移,并通过比较计算值和实验值得到不同理论计算方法的误差范围. 用HF和DFT理论计算芳环碳的化学位移时,CSGT方法比GIAO方法更为准确. 与其它方法相比,B3PW91//CSGT 在6-311G(d,p)基组下得到的芳环碳的化学位移最接近实验值. 采用B3LYP//GIAO计算时, 使用不同的基组 6-31G(d,p)和6-311++G(3df,3pd)得到的化学位移计算值只有δ 0.01~2.04的差异. MP2方法非常耗时,且对于计算精度的改善并不显著; 并且,由于电子相关性的影响,碳原子周围的电子环境对化学位移计算的准确性影响很大. 与实验值比较,HF方法由于忽略电子相关效应所以表现较差. 另外,碳链的增长对计算准确性也存在一定影响.   相似文献   

14.
介绍了经典非Abel等离子体满足的动力论方程及求解的方法.同时考虑夸克与反夸克贡献得到解析的有效质量(同时包含温度和化学势)的表达式,进而推出包含化学势的硬热圈自能,和场论所得结果完全一致.  相似文献   

15.
U. Turgut 《Pramana》2004,63(5):969-975
Chemical effects on the K shell fluorescence yields of Fe, Mn, Co, Cr and Cu compounds were investigated. Samples were excited using 59.5 keV energy photons from a241 Am radioisotope source. K X-rays emitted by samples were counted by a Si(Li) detector with a resolution 160 eV at 5.9 keV. Chemical effects on the K shell fluorescence yields (ωk) for Fe, Mn, Co, Cr and Cu compounds were observed. The values are compared with theoretical, semiempirical fit and experimental ones for the pure elements.  相似文献   

16.
Poly(N-methylaniline)/montmorillonite (PNMA/MMT) composite particles were obtained by using a simple in situ chemical oxidative polymerization method in hydrochloric acid solutions. Fourier transform infrared (FTIR) spectra, UV-visible absorption spectra and scanning electron microscopy (SEM) were carried out to characterize the as-prepared PNMA/MMT composite. On the basis of spectroscopy and morphology analysis, the probable polymerization mechanism was proposed. The potential application of PNMA/MMT composite for removal of heavy metal ions, such as Cu2+ and Zn2+, in aqueous solution was also investigated.  相似文献   

17.
甲基过氧化氢(CH3OOH)是大气中一种主要的有机过氧化物,它的生成和去除过程将影响大气自由基的浓度水平。文章利用长光路傅里叶变换红外光谱(LP-FTIR) 原位跟踪技术,实验室模拟研究了CH3OOH在常温和常压大气条件下的紫外光解反应,发现光解产物为HCHO,HC(O)OH,CH3OH,CO和CO2,此外实验中还观测到OH自由基的生成。根据分析结果推测了反应机理,并讨论了其大气化学意义。  相似文献   

18.
Summary We have applied the Tiwary approach to calculate the opticaloscillator strengths, of both the length and velocity forms, for the inner-shell excitation1s 2 2s 2 2p 6 3s 2 S e →1s 2 2s 2 2p 5 3s 2 2 P 0 transition in Ca X, Sc XI, Ti XII, Cu XIX, Zn XX, Br XXV and Kr XXVI ions of the sodium isoelectronic sequence employing Hartree-Fock (HF) and configuration interaction (CI) wave functions of both the initial and final states involved in the transition. Our present calculated results demonstrate that the Tiwary approach is capable of yielding encouraging results. A part of this work was done while the author was Research Director and Professor, CNRS Laboratory, University of Paris-Sud and Observatoire de Paris, Meudon, Paris, France.  相似文献   

19.
Summary Optical-oscillator strengths, of both the length and the velocity forms, for the inner-shell excitation 1s 22s 22p 63s 2 S e→1s 22s 22p 53s 2 2 P o transition, which leads to autoionization (Auger transition), in P V, S VI, Cl VII, Ar VIII and K IX ions of the sodium isoelectronic sequence have been calculated using the approach suggested by one of us (Tiwary) in the case of the Fe XVI ion. Our present calculated results demonstrate that the Tiwary approach is capable of yielding encouraging results. A part of this work was done while the author was Research Director and Professor, CNRS Laboratory, University of Paris-Sud, Paris and Observatoire de Paris, Meudon, Paris, France.  相似文献   

20.
The properties of boron nitride (BN), boron phosphide (BP), aluminum nitride (AlN), and aluminum phosphide (AlP) nanocones were investigated by density functional theory (DFT) calculations. The investigated structures were optimized and chemical shielding (CS) properties including isotropic and anisotropic CS parameters were calculated for the atoms of the optimized structures. The magnitudes of CS parameters were observed to be mainly dependent on the bond lengths of considered atoms. The results indicated that the atoms could be divided into atomic layers due to the similarities of their CS properties for the atoms of each layer. The trend means that the atoms of each layer detect almost similar electronic environments. Moreover, the atoms at the apex and mouth of nanocones exhibit different properties with respect to the other atomic layers.  相似文献   

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