国家预印本平台

The high density fuels, including uranium monocarbide UC, UN, and the uranium carbonitride U(CN) that results from carbon impurities following UN fabrication, have recently attracted attention for light-water reactor (LWR) applications because of their facilitation on increased 235 U loading at a fixed enrichment, high thermal conductivity and high melting temperatures. Despite these favorable properties, numerous performance aspects must be evaluated before any lesser-studied uranium compounds become viable LWR fuel forms. This study is first to perform thermodynamic calculation to evaluate thermal stability pure UC and UN in a closed system mimicking Pressure-water reactor (PWR) coolant, based on which UN or UC is not thermodynamically stable in any aqueous electrochemical system during a cladding breach. Then the potential interactions between UN and UCN with Zr or SiC cladding were systematically evaluated using a thermodynamic database of U-Zr-Si-C-N was developed in this work using the CALPHAD approach and validated with available literature data. The interfacial stability of UN/Zr, UC/Zr, UN/SiC and UC/SiC were assessed by calculating the isothermal sections U-Zr-N, U-Zr-C, U-Si-C, U-Si-C-N at 1500,1000 and 500 C, as well as the isopleth sections of U(C 0.3 N 0.7 )-Zr. The results predict that a complex reaction pathway between UN and Zr will produce multiple layers including phases of bcc(U,Zr), UZr2, hcp(Zr,N) and fcc(U,Zr)N. This response is more complicated than that between UC and Zr where a single ZrC layer is predicted. Improved thermodynamic stability is predicted when compatability with SiC cladding is considered. Both UN and UC are in equilibrium with SiC when modeled under the same temperature conditions. Potential carbon impurities present in UN as a result of the fabrication process were not found to contribute detrimentally to fuel-cladding contact for either Zr or SiC cladding under conditions evaluated here.

背景  中医药在慢性阻塞性肺疾病(以下简称慢阻肺)临床治疗中广泛运用，疗效显著，但相关临床试验的结局指标尚未得到统一和规范，中医药的疗效未充分展现，在一定程度上限制了中医药的学科发展。目的  为充分展现中医药临床疗效，构建中医药治疗慢阻肺临床疗效评价指标体系，规范中医药疗效指标，彰显中医药特色与优势。方法  通过文献检索时间为2020-01-01—2023-04-20及患者问卷构建条目池，遴选全国呼吸方向中医、中西医临床，护理，循证方法学专家37名，进行3轮德尔菲专家咨询构建中医药治疗慢阻肺临床疗效评价指标体系，运用层次分析法计算各指标权重。结果  三轮专家咨询积极系数分别为和100.0%、97.2%、94.3%；第三轮稳定期、急性加重期肯德尔协调系数（Kendall's W 系数）分别为0.550和0.475（P<0.001）；最终构建出稳定期包括6个一级指标，21个二级指标；急性加重期6个一级指标，28个二级指标的中医药治疗慢阻肺临床疗效评价指标体系。其中稳定期一级指标权重：中医病证（0.065）、症状体征（0.113）、理化检查（0.113）、生活质量（0.113）、远期预后（0.554）、安全性（0.042）。急性加重期一级指标权重：中医病证（0.044）、症状体征（0.301）、理化检查（0.124）、生活质量（0.085）、远期预后（0.315）、安全性（0.131）。结论  构建了一套综合性的中医药临床疗效评价指标体系，同时突出了中医药辨治优势在于防治，疗效长远，远期预后权重最高，可为中医药治疗慢阻肺临床疗效评价指标规范化提供参考。

在全球初级卫生保健（PHC）体系转型的背 景下，“以患者为中心的医疗之家”（PCMH）以其“以人为本的整合式连续化团队服务”的核心理念，已成为提升 PHC 服务质量的重要范式。我国社区卫生服务正处于从疾病治疗向健康管理深度转型的关键阶段，家庭医生签约服务与分级诊疗等制度的深入推进，为吸收并融合 PCMH 理念提供了实践土壤。本文系统梳理 PCMH 的核心要素与国际实践经验，通过对比我国社区卫生服务体系现状，识别出在支付激励、信息技术、人力资源、服务文化、组织管理与系统协同六个关键维度的结构性差异与转型挑战，进而提出相应的协同改革策略。在此基础上，研究构建了一个包含“组织准备、流程重塑、全面推广、持续改进”四个阶段的、循序渐进的实施路径，以期为推动我国家庭医生签约服务实现从“重签约”到“重服务”、从“碎片化”到“整合化”的高质量发展，提供兼具理论系统性与实践操作性的参考。

Shape quantum phase transition is an important and hot topic in nuclear structure. In this paper, we begin to study the finite-N shape quantum phase transition in the SU3-IBM. In this new proposed model, new spherical-like γ-soft spectra was found to resolve the spherical nucleus puzzle, which is a new γ-soft rotational mode. In this paper, the shape phase transition along the new γ-soft line is first discussed, and then the neighbouring case at the prolate side is also studied. Some key quantities are discussed. We find that double shape phase transitions occur along a single parameter path. The new γ-softness is really a shape phase and the shape phase transition from the new γ-soft phase to the prolate shape is found. The experimental supports are also found and108Pd may be the critical nucleus.

To further study the heavy-ion nuclear reaction mechanisms and fission of actinide nuclides by using the surrogate reaction method, a compact and efficient hybrid detector array for coincidence measurements of the beam-like particles and fission fragments has been developed and tested online. This detector array consists of four silicon strip detector telescopes and two parallel-plate avalanche counters. For the near-barrier \(^{7}\mathrm{Li} + ^{238}\mathrm{U}\) reaction, the fission fragments correlated with the beam-like \(^{6}\mathrm{He}\) particles originating from the transfer reaction were confirmed by analyzing the folding angle. The fission barrier height for the short-lived actinide nucleus \(^{239}\mathrm{Np}\), produced in the \(1p\) stripping channel, was extracted from its fission probability. The deduced value shows a good agreement with the existing literature data.