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Failure mechanisms and destruction characteristics of cemented coal gangue backfill under compression effect of non-uniform load

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Journal of Central South University 2024年第8期31卷 2676-2693页

作者： Feng, Guo-rui Guo, Wei Qi, Ting-ye Li, Zhu Cui, Jia-qing Wang, hao-chen Cui, Ye-kai Ma, Jing-kai College of Mining Engineering Taiyuan University of Technology Taiyuan China Shanxi Province Research Center of Green Mining Engineering Technology Taiyuan China Shanxi Province Coal-based Resources Green and High-efficiency Development Engineering Center Taiyuan China Shanxi Key Laboratory of Mine Rock Strata Control and Disaster Prevention Taiyuan China

Backfill mining is one of the most important technical means for controlling strata movement and reducing surface subsidence and environmental damage during exploitation of underground coal resources. Ensuring the stability of the backfill bodies is the primary prerequisite for maintaining the safety of the backfilling working face, and the loading characteristics of backfill are closely related to the deformation and subsidence of the roof. Elastic thin plate model was used to explore the non-uniform subsidence law of the roof, and then the non-uniform distribution characteristics of backfill bodies’ load were revealed. Through a self-developed non-uniform loading device combined with acoustic emission (AE) and digital image correlation (DIC) monitoring technology, the synergistic dynamic evolution law of the bearing capacity, apparent crack, and internal fracture of cemented coal gangue backfills (CCGBs) under loads with different degrees of non-uniformity was deeply explored. The results showed that: 1) The uniaxial compressive strength (UCS) of CCGB increased and then decreased with an increase in the degree of non-uniformity of load (DNL). About 40% of DNL was the inflection point of DNL-UCS curve and when DNL exceeded 40%, the strength decreased in a cliff-like manner; 2) A positive correlation was observed between the AE ringing count and UCS during the loading process of the specimen, which was manifested by a higher AE ringing count of the high-strength specimen. 3) Shear cracks gradually increased and failure mode of specimens gradually changed from “X” type dominated by tension cracks to inverted “Y” type dominated by shear cracks with an increase in DNL, and the crack opening displacement at the peak stress decreased and then increased. The crack opening displacement at 40% of the DNL was the smallest. This was consistent with the judgment of crack size based on the AE b-value, i.e., it showed the typical characteristics of “small b-value-large crack and

关键词： cemented coal gangue backfill crack opening displacement degree of non-uniformity of load failure mode non-uniform load

Network pharmacology-based exploration of molecular mechanisms underlying therapeutic effects of Jianpi Huatan Quyu recipe on chronic heart failure with spleen Qi deficiency syndrome

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World Journal of Cardiology 2024年第7期16卷 422-435页

作者： Si-Qi Li Dong-Yu Min Jun-Wen Jiang Xiao-Ying Li Xu-Na Yang Wen-Bo Gu Jia-Hui Jiang Li-hao chen Han Nan Ze-Yu chen Second Department of Cardiology The Affiliated Hospital of Liaoning University of Traditional Chinese MedicineShenyang 110000Liaoning ProvinceChina

BACKGROUND Chronic heart failure is a complex clinical *** Chinese herbal compound preparation Jianpi Huatan Quyu recipe has been used to treat chronic heart failure;however,the underlying molecular mechanism is still not *** To identify the effective active ingredients of Jianpi Huatan Quyu recipe and explore its molecular mechanism in the treatment of chronic heart *** The effective active ingredients of eight herbs composing Jianpi Huatan Quyu recipe were identified using the Traditional Chinese Medicine Systems Pharmacology Database and Analysis *** target genes of chronic heart failure were searched in the Genecards *** target proteins of active ingredients were mapped to chronic heart failure target genes to obtain the common drugdisease targets,which were then used to construct a key chemical componenttarget network using Cytoscape 3.7.2 *** protein-protein interaction network was constructed using the String *** Ontology and Kyoto Encyclopedia of Genes and Genomes enrichment analyses were performed through the Metascape ***,our previously published relevant articles were searched to verify the results obtained via network *** A total of 227 effective active ingredients for Jianpi Huatan Quyu recipe were identified,of which quercetin,kaempferol,7-methoxy-2-methyl isoflavone,formononetin,and isorhamnetin may be key active ingredients and involved in the therapeutic effects of TCM by acting on STAT3,MAPK3,AKT1,JUN,MAPK1,TP53,TNF,HSP90AA1,p65,MAPK8,MAPK14,IL6,EGFR,EDN1,FOS,and other *** pathways identified by KEGG enrichment analysis include pathways in cancer,IL-17 signaling pathway,PI3K-Akt signaling pathway,HIF-1 signaling pathway,calcium signaling pathway,cAMP signaling pathway,NF-kappaB signaling pathway,AMPK signaling pathway,*** studies on Jianpi Huatan Quyu recipe suggested that this Chinese compound preparation can regulate the TNF-α,IL-6,MAPK

关键词： Jianpi Huatan Quyu recipe Traditional Chinese medicine Chronic heart failure Data mining Network pharmacology Bioinformatics Spleen Qi deficiency syndrome

人口收缩型中小城市建设用地供应动态特征及分异

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资源科学 2024年第2期46卷 321-335页

作者：周臻陈浩王磊南京大学建筑与城市规划学院南京210093 中国科学院南京地理与湖泊研究所南京210008

【目的】收缩型中小城市普遍存在人口收缩-建设用地扩张的矛盾现象,解析建设用地供应动态特征是深入理解其机理的基础。【方法】使用中国土地市场网交易数据,基于倾向得分匹配模型遴选对照城市,解析71个收缩型中小城市样本相对于增长型... 详细信息

【目的】收缩型中小城市普遍存在人口收缩-建设用地扩张的矛盾现象,解析建设用地供应动态特征是深入理解其机理的基础。【方法】使用中国土地市场网交易数据,基于倾向得分匹配模型遴选对照城市,解析71个收缩型中小城市样本相对于增长型中小城市样本的建设用地供应动态特征(组间差异);基于系统聚类分析,探讨收缩型中小城市建设用地供应的差异特征(组内差异);基于Logistic回归,分析组间和组内供地差异形成的关键主导因素。【结果】①相比对照城市,收缩型中小城市建设用地供应特征为规模降低,价格增长明显放缓,以划拨等非市场化方式供地的比重、交通和公共设施等非经营性和非产业供地比重有较快扩大的趋势。其中,东北地区还表现为供地规模较大但价格普遍较低的区域性特征。②依据建设用地供应特征,71个收缩型中小城市样本可降维并归纳为“低水平供给型”“供给退化型”“弱增长供给型”3种类型。其中,“低水平供给型”城市多为传统农业型城市,建设用地市场发育程度较低;“供给退化型”城市多为重工业衰退城市,建设用地市场呈衰退态势;“弱增长供给型”城市多为增长区域内的人口外流城市,建设用地市场稳定发展但存在衰退风险。③组间供地差异主要与人口和产业发展等需求因素相关,组内供地差异则主要与政府供给因素和工业发展水平相关。【结论】收缩型中小城市的建设用地供应显示出群体性特征和内部差异。尽管收缩城市的建设用地供应可以被地方政府短期改变,但往往会在长时期的波动中回归到人口和产业等发展条件决定的真实水平,因此人-地增长悖论在一定程度上将有所纠正。据此,对收缩型中小城市的国土空间规划、城市更新等工作提出了政策建议。

关键词：收缩城市建设用地供应区域差异国土空间规划城市更新倾向得分匹配中国

土壤中Sb(Ⅲ)和Sb(Ⅴ)的有效提取与测定

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同济大学学报（自然科学版） 2024年第8期52卷 1270-1277页

作者：陈皓刘硕勋陈玲杨超同济大学污染控制与资源化研究国家重点实验室上海200092 同济大学环境科学与工程学院上海200092

锑的各种形态中三价锑和五价锑的毒性较高,在城市土壤锑组成中占比也较高。研究了萃取方式、萃取剂、萃取条件、色谱分离流动相条件等因素对土壤中价态锑提取和分析的影响,建立了完整的土壤价态锑萃取-分析方法。研究推荐以柠檬酸溶液... 详细信息

锑的各种形态中三价锑和五价锑的毒性较高,在城市土壤锑组成中占比也较高。研究了萃取方式、萃取剂、萃取条件、色谱分离流动相条件等因素对土壤中价态锑提取和分析的影响,建立了完整的土壤价态锑萃取-分析方法。研究推荐以柠檬酸溶液为萃取剂,70℃恒温振荡萃取的方式提取价态锑,萃取液以乙二胺四乙酸二钾+邻苯二甲酸为流动相,经色谱分离后利用电感耦合等离子体质谱仪对不同价态的Sb进行分析。所建立的方法检出限低,准确性精密度好,可用于实际土壤样品中价态锑的有效提取与测定。

关键词：价态锑道路土壤试剂萃取液相色谱-电感耦合等离子体质谱联用法

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一种相控阵雷达横滚角标校方法

数据采集与处理 2024年第1期39卷 132-139页

作者：陈皓雷艺中国电子科技集团公司第三十八研究所孔径阵列与空间探测安徽省重点实验室合肥230031 合肥工业大学计算机与信息学院合肥230601

提出了一种相控阵雷达横滚角标校方法,利用相控阵雷达横滚角与目标俯仰角测量误差之间的近似线性关系,结合雷达自带的角度测量误差标定手段,快速地计算得到雷达的横滚角,进而大幅提高相控阵雷达的角度测量精度。实验证明,使用该方法计... 详细信息

提出了一种相控阵雷达横滚角标校方法,利用相控阵雷达横滚角与目标俯仰角测量误差之间的近似线性关系,结合雷达自带的角度测量误差标定手段,快速地计算得到雷达的横滚角,进而大幅提高相控阵雷达的角度测量精度。实验证明,使用该方法计算得到的横滚角与使用激光测量仪器测得的横滚角结果精度相当,完全能够满足高精度测量雷达的需求。

关键词：相控阵雷达横滚角标校测量误差

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智媒传播场域下“技术中立”的法律难题解构

华中科技大学学报（社会科学版） 2024年第4期38卷 60-71页

作者：顾晨昊北京师范大学法学院

智媒传播场域下,“技术中立”的论调成为智能算法自动化决策与法律责任界定的难题。然而,“技术中立”的概念使用实际上杂糅了技术哲学中的“技术无涉价值论”、立法技术上的“技术中立理念”、版权法领域的“技术中立原则”三方内涵,... 详细信息

智媒传播场域下,“技术中立”的论调成为智能算法自动化决策与法律责任界定的难题。然而,“技术中立”的概念使用实际上杂糅了技术哲学中的“技术无涉价值论”、立法技术上的“技术中立理念”、版权法领域的“技术中立原则”三方内涵,导致概念混淆。“技术中立”难题的解构关键在于概念检视:一是在价值评析层面揭示技术内涵的社会维度,证成算法决策结果归责的正当性;二是明晰“技术中立理念”的内涵,排除制度设计层面的概念干扰;三是阐明“技术中立原则”的规则演变及法律适用条件,指正其在责任界定中有限的抗辩效果。基于历史视野,“技术中立”的技术治理观已无法适配当下的算法治理场景,应以“算法向善”为导向,在规范层面转变技术治理模式。

关键词：算法决策技术中立法律责任算法向善

固定平台桩腿焊缝热影响区裂纹缺陷的原因分析及改进建议

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船海工程 2024年第S1期53卷 126-129,136页

作者：陈昊中国船级社湛江分社广东湛江524000

针对某固定平台在建造过程中被发现桩腿立柱对接焊缝热影响区在焊后出现的裂纹缺陷,通过对母材材料情况、焊接工艺和焊接材料、焊接过程的控制三个方面进行分析,提出解决方案,最后结合该事件的分析处理进一步提出合理化的改进建议。

关键词：固定平台焊缝热影响区裂纹分析建议

TRIANGLE operation,combined with adequate adjuvant chemotherapy,can improve the prognosis of pancreatic head cancer:A retrospective study

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World Journal of Gastrointestinal Oncology 2024年第5期16卷 1773-1786页

作者： Jia-hao chen Li-Yong Zhu Zhi-Wei Cai Xiao Hu Abousalam Abdoulkader Ahmed Jie-Qiong Ge Xiao-Yan Tang Chun-Jing Li Yun-Long Pu Chong-Yi Jiang Department of Hepato-Biliary-Pancreatic Surgery Huadong Hospital Affiliated to Fudan UniversityShanghai 200040China Shanghai Key Laboratory of Clinical Geriatric Medicine Fudan UniversityShanghai 200040China Department of Nursing Huadong Hospital Affiliated to Fudan UniversityShanghai 200040China

BACKGROUND The TRIANGLE operation involves the removal of all tissues within the triangle bounded by the portal vein-superior mesenteric vein,celiac axis-common hepatic artery,and superior mesenteric artery to improve patient *** previously promising in patients with locally advanced pancreatic ductal adenocarcinoma(PDAC),data are limited regarding the long-term oncological outcomes of the TRIANGLE operation among resectable PDAC patients undergoing pancreaticoduodenectomy(PD).AIM To evaluate the safety of the TRIANGLE operation during PD and the prognosis in patients with resectable *** This retrospective cohort study included patients who underwent PD for pancreatic head cancer between January 2017 and April 2023,with or without the TRIANGLE *** were divided into the PD_(TRIANGLE)and PD_(non-TRIANGLE)*** and survival outcomes were compared between the two *** adjuvant chemotherapy was defined as adjuvant chemotherapy≥6 *** The PD_(TRIANGLE)and PD_(non-TRIANGLE) groups included 52 and 55 patients,*** were no significant differences in the baseline characteristics or perioperative indexes between the two ***,the recurrence rate was lower in the PD_(TRIANGLE) group than in the PD_(non-TRIANGLE) group(48.1%vs 81.8%,P<0.001),and the local recurrence rate of PDAC decreased from 37.8%to 16.0%.Multivariate Cox regression analysis revealed that PD_(TRIANGLE)(HR=0.424;95%CI:0.256-0.702;P=0.001),adequate adjuvant chemotherapy≥6 months(HR=0.370;95%CI:0.222-0.618;P<0.001)and margin status(HR=2.255;95%CI:1.252-4.064;P=0.007)were found to be independent factors for the recurrence *** The TRIANGLE operation is safe for PDAC patients undergoing ***,it reduces the local recurrence rate of PDAC and may improve survival in patients who receive adequate adjuvant chemotherapy.

关键词： TRIANGLE operation Pancreatic ductal adenocarcinoma Heidelberg triangle Adjuvant chemotherapy Prognosis Pancreaticoduodenectomy

高水平金融开放拓展中国式现代化发展空间的机制与路径研究

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新疆大学学报（哲学社会科学版） 2024年第4期52卷 82-92页

作者：陈灏钟锦宸福建商学院金融学院福建福州350001 复旦大学马克思主义学院上海200433

金融是现代经济的核心,高水平金融开放应当成为用好国内国际两种资源,拓展中国式现代化发展空间的关键一环。文章通过对金融资本空间化介入经济循环的政治经济学分析,认为金融开放与中国式现代化的空间逻辑紧密相连,并遵循“生成—延展... 详细信息

金融是现代经济的核心,高水平金融开放应当成为用好国内国际两种资源,拓展中国式现代化发展空间的关键一环。文章通过对金融资本空间化介入经济循环的政治经济学分析,认为金融开放与中国式现代化的空间逻辑紧密相连,并遵循“生成—延展—巩固”的递进式逻辑链路,分别从要素配置空间、融资合作空间以及安全韧性空间三大维度阐释了高水平金融开放拓展中国式现代化发展空间的作用机制。基于此,提出应以更广泛的金融开放范围,吸引国际金融资源,促进国内要素优化配置与价值提升;以更多维的金融开放领域,聚焦更为前沿、交叉复合的国际金融合作,把握新兴金融业态增长点;以更深入的金融开放层次,积极参与全球经济金融治理与新秩序构建,防范化解重点风险,确保金融市场统筹好开放发展和经济安全,继而持续拓展中国式现代化的发展空间。

关键词：高水平金融开放中国式现代化逻辑链路发展空间