宇宙锂问题是核天体物理前沿热点之一。在过去几十年中，各界科学家做了大量的工作来研究如何在标准大爆炸模型下解决该问题，但是迄今依然没有成功。随着暗物质研究迅猛发展，近些年国际上提出了多种通过引入神秘的暗物质候选粒子来解决宇宙锂问题的方法，然而诸多方法都是基于假设新引入的粒子成分不影响宇宙热动力学演化，单纯在大爆炸末期参与核合成或者大爆炸结束后引发非热核合成过程。本工作在我们先前工作的基础上从考虑引入的暗物质粒子会影响宇宙动力学演化这一新视角来研究宇宙初期核合成。不对现有已知物理做任何人为改变，在标准模型下引入暗物质粒子，通过研究宇宙热动力学的变化对核合成的影响来寻找解决宇宙锂问题的新方案，同时通过新内容下的大爆炸核合成理论预言与天文观测的比较来限制暗物质粒子的性质。

Cosmological lithium problem is a hot topic in nuclear astrophysics. In past decades, bulk of efforts from nuclear and particle physicists and astrophysicists have been devoted to the study of solving lithium problem in standard Big Bang Nucleosynthesis (BBN) model, but it remains unsolved up to now. With the rapid development of study in dark matter, many new approaches are devised to solve the lithium discrepancy by introducing mysterious particles, regarded as the candidates of dark matter. However, all of these solutions are based on the hypothesis that new particles have no influence on the thermodynamic evolution of universe, but will participate nucleosynthesis only in late stage of BBN or induce non-thermal nucleosynthesis process after BBN. Based on our previous work, the present study is devoted to investigating primordial nucleosynthesis from a new perspective in consideration of dark matter particle having an appreciable influence on the thermodynamic evolution of universe. Without any artificial variation of fundamental contents in our current physics, we attempt to find a new solution to primordial lithium problem by investigating the impact of alteration of cosmological thermodynamics on primordial nucleosynthesis in a scenario of dark matter particles involved in standard model. Meanwhile, we also try to derive constraints on the properties of dark matter particles by comparing the new BBN predictions with astronomical observations.