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Provenance and paleogeographic evolution of the Upper Paleozoic–Lower Mesozoic strata in northern Laos

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Journal of Earth Science 2024年

作者： jingjie jin Xin Qian Vongpaseuth senebouttalath Yuzhi Zhang Yuejun Wang Guangdong Provincial Key Lab of Geodynamics and Geohazards， School of Earth Sciences and Engineering， Sun Yat-sen University， and Southern Marine Science and Engineering Guangdong Laboratory (Zhuhai) Ministry of Energy and Mines， Department of Geology and Minerals

The Late Paleozoic–Early Mesozoic sedimentary system of the Luang Prabang Paleotethyan back-arc basin in northern Laos is important for investigating sedimentary provenance， paleogeographic patterns， and the tectonic evolution of the Eastern Paleotethyan Ocean. This study presents systematic stratigraphy， petrology， geochemistry， and detrital zircon U–Pb–Hf isotopic analyses for the Late Carboniferous–Jurassic sedimentary strata on both sides of the Luang Prabang basin. Based on distinct stratigraphic ages and provenance characteristics， the clastic rock samples can be divided into four groups. The Group 1 Late Carboniferous–Early Permian samples from the western part of the basin yield detrital zircon age-peaks of ～348 and ～1425 Ma， with corresponding εHf(t) values ranging from -2.0 to +15.5 and +1.5 to +14， respectively. The age spectrum of Group 2 Late Carboniferous–Early Permian samples from the eastern part of the basin shows major age-peaks of ～287 and ～1860 Ma， with εHf(t) values of -5.9–-0.9 and -3.6–+4.2， respectively. Group 3 Late Permian–Triassic samples exhibit age-peaks of ～242 and ～1853 Ma， along with εHf(t) values of -0.7–+14.4 and -5.4–-1.8， respectively. Group 4 Middle–Late Jurassic samples yield age-peaks of ～237，～431，～813，～1833， and ～2460 Ma， lacking Late Devonian (413–345 Ma) detrital zircons. All these data collectively suggest that the Group 1 sample primarily originated from the Sukhothai Arc in western Indochina， Group 2 was from the Kontum and Truong Son in eastern Indochina， and Group 3 has a combined provenance of the Sukhothai， Kontum， and Truong Son. Regional comparisons suggest that the Jurassic provenance was mainly derived from South China， which was imported through the northern river system. Our data， combined with the regional angular unconformities between Jurassic continental strata and pre-Jurassic marine strata， suggest that the Luang Prabang basin transformed into a superimposed collisional retroforeland basin during the Ju

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PBC模式下单部件加速退化系统的视情维修策略优化

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制造业自动化 2024年第2期46卷 68-75页

作者：莫亲鑫沈瑾苌道方上海海事大学物流科学与工程研究院上海201306 上海电机学院商学院上海201306

随着制造业向高质量服务型制造方向的转化,售后保障服务收入在企业收益中的比重不断增大,近年来PBC(Performance-BasedContract,PBC)模式在国外逐渐兴起,成为资本密集型企业的主要售后保障模式。针对一个单部件退化系统,提出了一种新的... 详细信息

随着制造业向高质量服务型制造方向的转化,售后保障服务收入在企业收益中的比重不断增大,近年来PBC(Performance-BasedContract,PBC)模式在国外逐渐兴起,成为资本密集型企业的主要售后保障模式。针对一个单部件退化系统,提出了一种新的基于服务性能合同(PBC)的视情维修策略。首先,以Gamma分布对退化过程建模,考虑系统退化速度会随役龄或维修次数的增加而逐渐加快的情况,采用完美维修和不完美维修两种维修操作,不完美维修的维修时间会随着系统的退化水平和维修次数而随机改变。在此基础上,以利润最大化为目标,通过评估系统的长期维修成本率和平均可用性,基于改进的粒子群算法得到了最优视情维修策略。最后,通过数值算例和模型参数敏感性分析,验证了模型的适用性,相比传统成本模型,绩效模型在利润收入上提高了11.6%,在系统可用度上提高了2.4%。

关键词：视情维修绩效合同不完美维修加速退化系统优化

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肿瘤干细胞与免疫微环境调控

生物化学与生物物理进展 2024年第10期51卷 2545-2559页

作者：朱平平靳水玲赵奇范祖森郑州大学生命科学学院郑州450001 郑州大学第一附属医院肿瘤科郑州450052 中国科学院生物物理研究所北京100101

肿瘤干细胞是肿瘤中一小群具有自我更新和分化能力的细胞,是肿瘤发生、转移、治疗抵抗和复发的关键。肿瘤干细胞处于特定微环境中,其数量维持、自我更新和分化均受到微环境的精细调控,其中免疫微环境是肿瘤干细胞最关键的微环境之一。... 详细信息

肿瘤干细胞是肿瘤中一小群具有自我更新和分化能力的细胞,是肿瘤发生、转移、治疗抵抗和复发的关键。肿瘤干细胞处于特定微环境中,其数量维持、自我更新和分化均受到微环境的精细调控,其中免疫微环境是肿瘤干细胞最关键的微环境之一。近年来肿瘤免疫疗法取得了较大成功,但是免疫治疗后耐药和复发频现,肿瘤干细胞与普通肿瘤细胞相比,具有更强的免疫逃逸能力,其在肿瘤免疫逃逸中的作用受到越来越多的关注。本文论述了肿瘤干细胞的发现历史和谱系来源,重点描述了肿瘤干细胞微环境中的免疫细胞类型,例如肿瘤浸润淋巴细胞、肿瘤相关巨噬细胞和肿瘤相关树突状细胞等,剖析了肿瘤干细胞-免疫细胞相互作用机制,并阐述了靶向肿瘤干细胞及其免疫微环境的干预策略。随着肿瘤干细胞-免疫细胞共培养、单细胞测序和谱系示踪等先进技术的发展和应用,通过靶向肿瘤干细胞与免疫细胞的相互作用或逆转免疫抑制性微环境,抑制肿瘤干细胞的免疫逃逸,有望为肿瘤免疫治疗的耐药和复发难题提供潜在解决方案。

关键词：肿瘤干细胞自我更新免疫微环境肿瘤免疫

Transient analysis on surface heated piezoelectric semiconductor plate lying on rigid substrate

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Applied Mathematics and Mechanics(English Edition) 2022年第12期43卷 1841-1856页

作者： Luke ZHAO sen GU Yaqin SONG Feng jin State Key Laboratory for Strength and Vibration of Mechanical Structures School of Aerospace EngineeringXi'an Jiaotong UniversityXi'an 710049China

Based on the thermo-electro-elastic coupling theory,the mathematical model for a surface heated piezoelectric semiconductor(PS)plate is developed in the time *** the direct and inverse Laplace transformations to the established model,the mechanical and electrical responses are *** comparison between the analytical solution and the finite element method(FEM)is conducted,which illustrates the validity of the *** calculated results show that the maximum values of the mechanical and electrical fields appear at the heating ***,the perturbation carriers tend to concentrate in the zone near the heating surface under the given boundary *** can also be observed that the heating induced elastic wave leads to jumps for the electric potential and perturbation carrier density at the *** the thermal relaxation time is introduced,all the field quantities become smaller because of the thermal lagging ***,it can be found that the thermal relaxation time can describe the smooth variation at the jump ***,for a plate with P-N junction,the effect of the interface position on the electrical response is *** effects of the initial carrier density on the electrical properties are discussed in *** conclusions in this article can be the guidance for the design of PS devices serving in thermal environment.

关键词： thermo-electro-elastic coupling piezoelectric semiconductor(PS) surface heating transient analysis

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秸秆收储运模式对运输成本的影响

能源与节能 2024年第1期 32-36页

作者：田亚超李森晋强新疆互力佳源环保科技有限公司新疆乌鲁木齐830063 新疆农业大学水利与土木工程学院新疆乌鲁木齐830052

以乌鲁木齐市为例,选取了10个储运点,分析不同秸秆收储运模式的特点,寻找经济可行的收储运模式,提升秸秆生物质的利用率。结果表明:秸秆运输成本占秸秆生物质燃料成本的比例较大;模式一适用于秸秆储存量不大、运输距离较近的收储运点;... 详细信息

以乌鲁木齐市为例,选取了10个储运点,分析不同秸秆收储运模式的特点,寻找经济可行的收储运模式,提升秸秆生物质的利用率。结果表明:秸秆运输成本占秸秆生物质燃料成本的比例较大;模式一适用于秸秆储存量不大、运输距离较近的收储运点;模式二对距离较远、储量小的收储运点较为适合;模式三适用于储量大的收储运点,收集快,运输距离短。3种模式各有利弊,应针对不同的地点选用最合适的方法。储量小,选择模式一;储量大,选择模式三;距离远,选择模式二。

关键词：生物质秸秆秸秆收储运收储运模式运输成本

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扁平大空间船舶火灾烟气控制试验研究

中国安全科学学报 2024年第5期34卷 162-167页

作者：李森王少鹏林锦陆守香李倩陈国庆中国科学技术大学火灾科学国家重点实验室安徽合肥230026 上海船舶工艺研究所上海200032 中国舰船研究设计中心湖北武汉430064 中国船级社上海规范研究所上海200135

为有效控制扁平大空间船舶火灾烟气蔓延,研究大尺度火灾过程中的油池质量损失速率、舱室温度分布、隔热效率和烟气控制效果。利用尺寸为30 m×24 m×2.3 m的模拟舱,在0.35、0.55和0.70 m等3种不同挡烟垂壁高度和机械通风条件下开展试验... 详细信息

为有效控制扁平大空间船舶火灾烟气蔓延,研究大尺度火灾过程中的油池质量损失速率、舱室温度分布、隔热效率和烟气控制效果。利用尺寸为30 m×24 m×2.3 m的模拟舱,在0.35、0.55和0.70 m等3种不同挡烟垂壁高度和机械通风条件下开展试验。结果表明:挡烟垂壁高度增加,油池质量损失速率峰值减小;挡烟垂壁高度对舱室上层烟气温度的影响比对下层气体温度的影响更明显,1.4 m以上空间温度峰值明显下降,而1.4 m以下空间温度峰值无明显变化。顶棚平均温度和隔热效率随挡烟垂壁高度增加而下降。随挡烟垂壁高度增加,火源区与非火源区同时控烟模式隔热效率从28.2%提升至50.8%,火源区单独控烟模式隔热效率从29.4%提升至54.7%。

关键词：扁平大空间船舶火灾烟气控制挡烟垂壁机械通风控烟模式隔热效率

Validation and performance of three scoring systems for predicting primary non-function and early allograft failure after liver transplantation

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Hepatobiliary & Pancreatic Diseases International 2024年第5期23卷 463-471页

作者： Yu Nie jin-Bo Huang Shu-Jiao He Hua-Di Chen Jun-Jun Jia jing-jing Li Xiao-Shun He Qiang Zhao General Surgery Center Department of Hepatobiliary Surgery IIResearch Center for Artificial Organ and Tissue EngineeringGuangzhou Clinical Research and Transformation Center for Artificial LiverInstitute of Regenerative MedicineZhujiang HospitalSouthern Medical UniversityGuangzhou 510515China Organ Transplant Center the First Affiliated HospitalSun Yat-sen UniversityGuangzhou 510080China Guangdong Provincial Key Laboratory of Organ Donation and Transplant Immunology Guangzhou 510080China Guangdong Provincial International Cooperation Base of Science and Technology Guangzhou 510080China Division of Hepatobiliary Pancreatic Surgery the First Affiliated HospitalZhejiang University School of MedicineHangzhou 310003China

Background: Primary non-function(PNF) and early allograft failure(EAF) after liver transplantation(LT) seriously affect patient outcomes. In clinical practice, effective prognostic tools for early identifying recipients at high risk of PNF and EAF were urgently needed. Recently, the Model for Early Allograft Function(MEAF), PNF score by King's College(King-PNF) and Balance-and-Risk-Lactate(BAR-Lac) score were developed to assess the risks of PNF and EAF. This study aimed to externally validate and compare the prognostic performance of these three scores for predicting PNF and EAF. Methods: A retrospective study included 720 patients with primary LT between January 2015 and December 2020. MEAF, King-PNF and BAR-Lac scores were compared using receiver operating characteristic(ROC) and the net reclassification improvement(NRI) and integrated discrimination improvement(IDI) analyses. Results: Of all 720 patients, 28(3.9%) developed PNF and 67(9.3%) developed EAF in 3 months. The overall early allograft dysfunction(EAD) rate was 39.0%. The 3-month patient mortality was 8.6% while 1-year graft-failure-free survival was 89.2%. The median MEAF, King-PNF and BAR-Lac scores were 5.0(3.5–6.3),-2.1(-2.6 to-1.2), and 5.0(2.0–11.0), respectively. For predicting PNF, MEAF and King-PNF scores had excellent area under curves(AUCs) of 0.872 and 0.891, superior to BAR-Lac(AUC = 0.830). The NRI and IDI analyses confirmed that King-PNF score had the best performance in predicting PNF while MEAF served as a better predictor of EAD. The EAF risk curve and 1-year graft-failure-free survival curve showed that King-PNF was superior to MEAF and BAR-Lac scores for stratifying the risk of EAF. Conclusions: MEAF, King-PNF and BAR-Lac were validated as practical and effective risk assessment tools of PNF. King-PNF score outperformed MEAF and BAR-Lac in predicting PNF and EAF within 6 months. BAR-Lac score had a huge advantage in the prediction for PNF without post-transplant variables. Proper use

关键词： Primary non-function Early allograft failure Risk predicting model Liver transplantation

羟基化石墨烯对粉煤灰-水泥基复合材料性能的影响

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材料导报 2024年第11期38卷 148-155页

作者：袁小亚蒲云东桂尊曜张惠一杨森金湛曹蔚琦重庆交通大学材料科学与工程学院重庆交通大学先进功能材料研究所重庆诺奖二维材料研究院重庆交通大学土木工程学院重庆大学光电工程学院光电技术及系统教育部重点实验室

石墨烯增强水泥基材料是目前该领域的研究热点，但石墨烯的分散性是该类研究的关键。因此，本工作采用不带羧基的羟基化石墨烯(HO-G)来研究不同掺量(0.01%、0.03%、0.05%、0.07%、0.09%,质量分数)对粉煤灰-水泥体系的工作性能、力学性... 详细信息

石墨烯增强水泥基材料是目前该领域的研究热点，但石墨烯的分散性是该类研究的关键。因此，本工作采用不带羧基的羟基化石墨烯(HO-G)来研究不同掺量(0.01%、0.03%、0.05%、0.07%、0.09%,质量分数)对粉煤灰-水泥体系的工作性能、力学性能和耐久性的影响。与粉煤灰-水泥体系相比，流动度测试表明HO-G对粉煤灰-水泥砂浆新拌浆体流动度影响不大；力学性能测试表明，HO-G能增强粉煤灰-水泥砂浆的力学性能，尤其是当HO-G的掺量为0.03%时，其28 d抗折、抗压强度分别提高了12.40%和18.48%;耐硫酸盐腐蚀和抗氯离子渗透的测试结果表明，HO-G的加入还能改善粉煤灰-水泥砂浆的耐久性。微观测试表明，粉煤灰和HO-G之间存在协同效应，HO-G能加速粉煤灰的二次水化反应以促进粉煤灰-水泥体系中更多的水化晶体生成，且凭借其模板效应可进一步规整水化晶体的生长模式和调控晶体排列结构，从而改善粉煤灰-水泥基体的微观形貌。

关键词：羟基化石墨烯水泥粉煤灰力学性能耐久性

Chaos Control and Bifurcation Behavior for a Sprott E System with Distributed Delay Feedback

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International Journal of Automation and computing 2015年第2期12卷 182-191页

作者： Chang-jin Xu Yu-sen Wu Guizhou Key Laboratory of Economics System Simulation Guizhou University of Finance and Economics School of Mathematics and Statistics Henan University of Science and Technology

In this paper, the problem of controlling chaos in a Sprott E system with distributed delay feedback is considered. By analyzing the associated characteristic transcendental equation, we focus on the local stability and Hopf bifurcation nature of the Sprott E system with distributed delay feedback. Some explicit formulae for determining the stability and the direction of the Hopf bifurcation periodic solutions are derived by using the normal form theory and center manifold theory. Numerical simulations for justifying the theoretical analysis are provided.

关键词： Sprott E system chaos control stability Hopf bifurcation distributed delay.