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Correlation between life satisfaction,pleasure level,and negative emotion in patients with chronic renal failure
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作者 Lin-Lin Zhang You-Li Zhang +3 位作者 Ting Liu Jian Wang Chen Chen Xiao-Yu Wang 《World Journal of Psychiatry》 2026年第1期291-298,共8页
BACKGROUND Anxiety,depression,and other negative emotions are common among patients with chronic renal failure(CRF).Analyzing the factors related to negative emotions is necessary to provide targeted nursing care.AIM ... BACKGROUND Anxiety,depression,and other negative emotions are common among patients with chronic renal failure(CRF).Analyzing the factors related to negative emotions is necessary to provide targeted nursing care.AIM To explore the correlations among life satisfaction,pleasure levels,and negative emotions in patients with CRF.METHODS One hundred patients with CRF who received therapy at the First Affiliated Hospital of Jinzhou Medical University between December 2022 and February 2025 were included.The Depression,Anxiety,and Stress Scale(DASS-21),Satisfaction with Life Scale(SWLS),and Temporal Experience of Pleasure Scale(TEPS)were used to evaluate negative emotions,life satisfaction,and pleasure level,respectively.Pearson’s correlation coefficient analyzed the correlation between life satisfaction,pleasure level,and negative emotions.Linear regression analysis identified the factors affecting negative emotions.RESULTS The average DASS-21 score among patients with CRF was 51.90±2.30,with subscale scores of 17.90±1.50 for depression,18.53±1.18 for anxiety,and 15.47±2.36 for stress,all significantly higher than the domestic norm(P<0.05).The average SWLS score was 22.17±4.90.Correlation analysis revealed a negative correlation between the SWLS and total DASS-21 scores(P<0.05),but not with the individual depression,anxiety,or stress dimensions.The average TEPS score was 67.80±8.34.TEPS scores were negatively correlated with the DASS-21 score and the stress dimension(P<0.05),but not with depression or anxiety.Linear regression analysis showed that TEPS scores significantly influenced DASS-21 scores(P<0.05).CONCLUSION Patients with CRF experience high levels of negative emotions,which are negatively correlated with life satisfaction and pleasure.Furthermore,pleasure level had an impact on negative emotions. 展开更多
关键词 Chronic renal failure HEMODIALYSIS negative emotion Life satisfaction PLEASURE CORRELATION
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西瓜NPR基因家族的鉴定及其在盐胁迫下的表达分析 被引量:1
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作者 贾云鹤 《中国瓜菜》 北大核心 2025年第1期16-24,共9页
以拟南芥NPR基因家族成员蛋白序列为查询序列,在西瓜基因组数据库中鉴定西瓜NPR基因家族成员,并对其进行生物信息学分析及盐胁迫下的表达分析。共鉴定到4个成员,将其命名为ClNPR1~ClNPR4,其编码蛋白的理化性质、保守功能结构域、重要氨... 以拟南芥NPR基因家族成员蛋白序列为查询序列,在西瓜基因组数据库中鉴定西瓜NPR基因家族成员,并对其进行生物信息学分析及盐胁迫下的表达分析。共鉴定到4个成员,将其命名为ClNPR1~ClNPR4,其编码蛋白的理化性质、保守功能结构域、重要氨基酸残基及motif分析结果与其他物种有较高的一致性,顺式作用元件分析显示,ClNPRs与非生物胁迫相关。300 mmol·L^(-1)NaCl处理耐盐材料和盐敏感材料,分别取盐胁迫0、8、24 h的叶片进行4个NPR基因的表达模式分析,结果表明,ClNPR1在盐敏感和耐盐材料中都显著上调表达,但盐胁迫24 h,ClNPR1在盐敏感材料中显著下调表达,在耐盐材料中虽然下调但还保持较高的表达水平,且在耐盐材料中的表达量显著高于盐敏感材料;盐胁迫24 h,ClNPR2和ClNPR3在盐敏感和耐盐材料中都显著上调表达,在耐盐材料中的表达量均显著高于盐敏感材料。推测ClNPRs基因在西瓜响应盐胁迫的过程中扮演重要角色。 展开更多
关键词 西瓜 npr家族蛋白 盐胁迫 表达
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不同锚固孔径下2G-NPR锚杆锚固特性试验研究 被引量:1
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作者 陶志刚 李梦楠 +2 位作者 于海军 范方政 王炯 《岩土力学》 北大核心 2025年第S1期67-80,共14页
为了更好地分析2G-NPR锚杆锚固特性,确定合理的锚杆直径与锚固孔径的匹配范围。以室内拉拔试验为基础,分析了不同锚固孔径下锚固体系破坏形式;建立了锚固体与锚固孔径匹配的力学模型,推导了沿锚固方向轴向力和界面剪应力理论计算公式;... 为了更好地分析2G-NPR锚杆锚固特性,确定合理的锚杆直径与锚固孔径的匹配范围。以室内拉拔试验为基础,分析了不同锚固孔径下锚固体系破坏形式;建立了锚固体与锚固孔径匹配的力学模型,推导了沿锚固方向轴向力和界面剪应力理论计算公式;通过有限差分程序FLAC3D建立不同锚固孔径下的拉拔模型,揭示了锚固系统的应力分布规律。结果表明:(1)在不同锚固孔径下,以直径匹配差值8 mm为界,锚固体系在达到最大承载能力时的破坏界面不同;(2)锚固体系在加载时荷载-位移曲线可分为预加载、弹性变形、塑性变形、界面开始脱黏、界面完全脱黏5个阶段;(3)拉拔力为30 kN条件下,随着锚固孔径增大,锚杆-锚固剂界面剪应力分布随孔径变化不大,但在螺旋状肋处有明显剪应力集中现象,相同位置锚杆-锚固剂界面剪应力是锚固剂-围岩界面剪应力的2~3倍,锚固剂-围岩界面剪应力分布随孔径增大而明显减小;(4)确定了直径为18 mm的2G-NPR锚杆最佳锚固孔径差值范围为8~12 mm。 展开更多
关键词 拉拔试验 2G-npr锚杆 锚固孔径 锚固性能 锚固失效形式
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峰前循环荷载作用下NPR锚杆锚固结构面抗剪强度特性研究
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作者 陶志刚 张腾伍 +1 位作者 洪陈杰 张海江 《金属矿山》 北大核心 2025年第9期78-87,共10页
NPR锚杆锚固结构面在静态剪切荷载作用下表现出超常抗剪性能,然而在动态循环荷载作用下的力学响应尚需进一步验证。采用经加工的原岩试样,进行均质砂岩结构面的峰前循环加载剪切试验,对比分析无锚固和NPR锚杆锚固2种工况下循环加载次数... NPR锚杆锚固结构面在静态剪切荷载作用下表现出超常抗剪性能,然而在动态循环荷载作用下的力学响应尚需进一步验证。采用经加工的原岩试样,进行均质砂岩结构面的峰前循环加载剪切试验,对比分析无锚固和NPR锚杆锚固2种工况下循环加载次数、加载速率、不同幅值等因素对结构面剪切强度的影响规律。结果表明:①循环次数为80次时,无锚固结构面的抗剪强度达到峰值;相比之下,NPR锚杆锚固结构面的峰值抗剪强度明显提升。②循环加载速率由1 kN/s增大至1.5 kN/s时,无锚固结构面抗剪强度下降较快;与此相反,NPR锚杆锚固结构面在加载速率增大时,峰值抗剪强度呈现更大的提升幅度。③循环加载幅值由50%τ_(max)增大至80%τ_(max),无锚固结构面抗剪强度降低;而NPR锚杆锚固结构面的抗剪强度增大,有效改善了未锚固结构面的脆性破坏特征。④不同法向应力下,NPR锚杆锚固结构面的抗剪强度均比无锚固结构面得到显著提升。上述研究结果可为露天矿开采的抗震和防爆设计提供科学依据。 展开更多
关键词 峰前循环加载 锚固剪切试验 岩体结构面 npr 锚杆
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拉伸荷载条件下新型NPR锚杆韧性材料宏观变形特征分析
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作者 陶志刚 隋麒儒 +3 位作者 丰于翔 孟志刚 姚旭龙 何满潮 《绿色矿山》 2025年第1期44-50,共7页
岩土工程在受到复杂地质条件的综合作用时极易产生大变形灾害响应,传统金属支护材料因不能够忍受大变形而发生失效破坏现象。为应对大变形灾害,研发了新型NPR锚杆韧性材料(Negative Poisson’s Ratiobolt)。为了探索新型NPR锚杆韧性材... 岩土工程在受到复杂地质条件的综合作用时极易产生大变形灾害响应,传统金属支护材料因不能够忍受大变形而发生失效破坏现象。为应对大变形灾害,研发了新型NPR锚杆韧性材料(Negative Poisson’s Ratiobolt)。为了探索新型NPR锚杆韧性材料的宏观变形特征,开展了NPR锚杆室内拉伸对比试验。采用NPR锚杆专用试验机,并利用相机进行全过程变形特征记录。结果发现:NPR锚杆具有更好的均匀变形特性,且在拉伸变形失效全过程早期阶段就开始发生均匀变形;对不同钢筋进行失效断口分类:主要分为“分层型断口”和“纤维-基体之间的界面破坏类断裂型断口”;通过力学机制分析NPR锚杆均匀变形特性及颈缩现象不显著的原因:发现NPR钢在拉伸变形失效后的颈缩处曲率半径更大,使其颈缩现象不明显,这是由于其最大均匀应变与最大应变差值相对较小所致;通过LS-DYNA算法对螺纹肋结构和光圆结构对于钢筋变形的影响进行数值模拟分析,结果证明螺纹肋结构使得钢筋在拉伸过程中能够更好地均匀变形,吸收变形能。综上所.述,通过对新型NPR锚杆韧性材料的变形特征的宏观分析,有助于更好地揭示其静力拉伸性能,为准静态工程实践提供了有价值的参考。 展开更多
关键词 韧性材料 npr锚杆 拉伸试验 变形特征 宏观分析
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Negative Poisson's ratio and peripheral strain of an NPR anchor cable 被引量:3
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作者 TAO Zhi-gang XU Hao-tian +3 位作者 REN Shu-lin GUO Long-ji QIN Ke ZHU Yi-fei 《Journal of Mountain Science》 SCIE CSCD 2022年第8期2435-2448,共14页
Materials with a negative Poisson’s ratio effect perform significantly better than traditional materials for rock mass impact resistance,shear resistance,and energy absorption.Based on these advantages,a negative Poi... Materials with a negative Poisson’s ratio effect perform significantly better than traditional materials for rock mass impact resistance,shear resistance,and energy absorption.Based on these advantages,a negative Poisson’s ratio anchor cable(NPR anchor cable)with high elongation and constant resistance was developed and successfully applied in the field of mine disaster control.However,theoretical and experimental research on the negative Poisson’s ratio effect and peripheral strain characteristics of NPR anchor cables is currently incomplete.This study used several theories and methods,such as static tensile,peripheral strain measurement,and static negative Poisson’s ratio measurement,to investigate the radial deformation law of an NPR anchor cable and the negative Poisson’s ratio characteristics.Experimental results elucidated constant resistance changes in an NPR anchor cable during operation,the motion of the constant resistance body in the constant resistance sleeve,and the deformation law of the constant resistance sleeve.Negative Poisson’s ratio characteristics of the NPR anchor cable and its superior energy absorption characteristics were verified and it provided a theoretical and experimental basis for energy absorption mechanisms of an NPR anchor cable. 展开更多
关键词 npr anchor cable Static tensile test negative Poisson’s ratio Energy absorption
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基于恒阻装置尺寸设计的NPR锚索力学性能优化研究
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作者 朱淳 徐佳俊 +4 位作者 何满潮 谭毅 陈佳敏 李海波 陈兵兵 《中南大学学报(自然科学版)》 北大核心 2025年第3期1113-1124,共12页
NPR锚索(恒阻大变形锚索)已广泛应用于采矿、水利、交通等工程领域,为适应深部工程复杂的地质条件,需适当调整NPR锚索的尺寸,以提高NPR锚索的力学性能,为此,本文开展了恒阻装置几何尺寸的设计参数对NPR锚索静/动力学性能的影响规律研究... NPR锚索(恒阻大变形锚索)已广泛应用于采矿、水利、交通等工程领域,为适应深部工程复杂的地质条件,需适当调整NPR锚索的尺寸,以提高NPR锚索的力学性能,为此,本文开展了恒阻装置几何尺寸的设计参数对NPR锚索静/动力学性能的影响规律研究。首先,使用ABAQUS有限元软件建立NPR锚索的静/动力仿真数值模型,并基于室内力学试验结果对其精准性进行验证。其次,采用正交试验法制定恒阻装置尺寸参数数值模拟方案,对不同尺寸参数下NPR锚索的静力拉伸和动力冲击参数进行模拟试验。最后,通过极差分析确定恒阻装置各尺寸参数对于NPR锚索力学性能的影响程度。研究结果表明,NPR锚索恒阻装置各尺寸在静力拉伸试验中对恒阻力值及其波动程度的影响程度排序与在动力冲击试验中对冲击阻力和能量吸收率的影响程度排序一致,影响程度排序由大到小依次为恒阻体后端直径、恒阻套筒厚度、恒阻体长度、恒阻体平台厚度。试验结果可为NPR锚索恒阻装置的优化设计提供参考。 展开更多
关键词 npr锚索 静/动力学性能 ABAQUS 正交试验 参数优化
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不同裂隙倾角NPR锚固岩体力学特性对比研究
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作者 缪澄宇 崔力 +2 位作者 孙晓明 谭雨泽 李志虎 《采矿与安全工程学报》 北大核心 2025年第4期779-788,共10页
裂隙岩体锚固力学特性是围岩支护设计的基本依据。针对新型负泊松比锚索(NPR)的支护效能,通过相似物理模型实验,对比研究不同预制裂隙倾角下NPR锚固体与普通(PR)锚固体力学特性差异,分析锚固体强度特性、变形破坏特性和声发射特性。随... 裂隙岩体锚固力学特性是围岩支护设计的基本依据。针对新型负泊松比锚索(NPR)的支护效能,通过相似物理模型实验,对比研究不同预制裂隙倾角下NPR锚固体与普通(PR)锚固体力学特性差异,分析锚固体强度特性、变形破坏特性和声发射特性。随着裂隙倾角的增大,锚固体应力-应变曲线形态由双峰值逐渐向单峰值演变,锚固体弹性模量先增大后减小,峰值强度不断增大,NPR锚固体弹性模量和强度均明显高于PR锚固体。考虑岩体峰值强度时,NPR锚索最佳支护倾角为60°~90°,而PR锚索仅在支护倾角90°时达到最优支护效果。2类锚固体均呈现拉剪复合破坏特征,但NPR锚索未破断,锚固体完整性好,而PR锚索发生破断,锚固体完整性差。NPR和PR锚固体内部分别在预制裂隙倾角为75°和45°之前产生剪切破坏,超过此角度后则转变为张拉破坏。NPR锚固体自由面变形小且较为均匀,局部位移差较小,而PR锚固体自由面变形较大且不均匀,局部位移差较大。声发射特征显示,由于NPR锚索的持久约束作用,锚固体振铃计数更为均匀,而PR锚固体振铃计数较大值则集中在应变初期锚索破断时刻。 展开更多
关键词 npr锚索 锚固体 相似实验 双轴压缩 力学特性
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外周血WBC、NPR、PLR在成人肺炎中的变化特征及其对病情评估和预后预测的价值
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作者 冯珊珊 孙静 +4 位作者 左芳 耿新普 盛丽丽 刘荣 赵峰 《分子诊断与治疗杂志》 2025年第12期2322-2324,2328,共4页
目的探究外周血白细胞计数(WBC)、中性粒细胞与血小板计数比值(NPR)、血小板与淋巴细胞比值(PLR)在成人肺炎中的变化特征及其对病情评估和预后预测的价值。方法将2022年1月至2025年1月南京医科大学康达学院附属涟水人民医院收治的104例... 目的探究外周血白细胞计数(WBC)、中性粒细胞与血小板计数比值(NPR)、血小板与淋巴细胞比值(PLR)在成人肺炎中的变化特征及其对病情评估和预后预测的价值。方法将2022年1月至2025年1月南京医科大学康达学院附属涟水人民医院收治的104例成人社区获得性肺炎患者纳入研究。根据患者的肺炎严重指数(PSI)分为低危组(66例,PSI≤90分)和高危组(38例,PSI>90分),再根据患者预后效果分为预后良好组(78例)和预后不良组(26例),比较不同病情严重程度及不同预后患者的外周血WBC、NPR、PLR水平,分析外周血指标与病情及预后的关系,使用ROC分析外周血指标对预后的预测价值,使用Logistic回归分析影响患者预后的危险因素。结果高危组外周血WBC、NPR、PLR均高于低危组,差异有统计学意义(P<0.05);经Spearman分析,外周血WBC、NPR、PLR与病情严重程度呈正相关性(P<0.05);预后不良组患者的外周血WBC、NPR、PLR水平均高于预后良好组,差异有统计学意义(P<0.05);经ROC分析,外周血WBC、NPR、PLR及联合检测对患者预后预测的曲线下面积分别为0.805、0.802、0.831、0.908(P<0.05),Logistic回归分析显示,外周血WBC≥13.08×10^(9)/L、NPR≥3.2、PLR≥175.60是影响成人社区获得性肺炎患者预后的危险因素(P<0.05)。结论外周血WBC、NPR、PLR水平会随成人肺炎患者病情加重而升高,可作为临床评估预后的辅助检测指标。 展开更多
关键词 社区获得性肺炎 白细胞计数 中性粒细胞与血小板计数比值 血小板与淋巴细胞比值
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3例NPR2基因变异相关矮小症临床分析及3种变异体外功能验证
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作者 张淑颖 连群 +2 位作者 蔡丽华 王辰璐 许珊珊 《罕少疾病杂志》 2025年第9期1-4,共4页
目的 厦门大学附属第一医院发现3例NPR2基因变异伴骨骼畸形的矮小患儿,拟通过国内外文献报道、生信分析及体外功能验证,对NPR2基因变异所致矮小患者的临床表现、治疗及可能致病的机制进行分析。方法 通过医院HIS系统对患者的临床资料进... 目的 厦门大学附属第一医院发现3例NPR2基因变异伴骨骼畸形的矮小患儿,拟通过国内外文献报道、生信分析及体外功能验证,对NPR2基因变异所致矮小患者的临床表现、治疗及可能致病的机制进行分析。方法 通过医院HIS系统对患者的临床资料进行收集汇总。对NPR2基因变异体进行软件功能预测。用慢病毒转染293T细胞构建野生型及3种变异型稳定转染细胞。用酶联免疫分析方法测定cGMP水平。用蛋白印迹方法测定NPRB蛋白表达量。结果 报道了2位携带NPR2基因p.R787W杂合变异的特发性矮小患者及1位NPR2基因p.E906G及p.R976H复合杂合变异的Maroteaux型肢端肢中发育不全(AMDM)患者,该2种变异均为新变异,尚未被文献报道。3名患者由不同程度的骨骼畸形。体外功能验证结果:与野生型细胞相比,3种变异型细胞c GMP水平均下降,差异具有统计学意义,其NPRB蛋白表达量无统计学差异。结论 对严重身材矮小且伴有骨骼畸形的患者,应进行基因检测寻找其遗传病因。NPR2基因变异导致矮小的机制尚不明确,仍需进一步探索。 展开更多
关键词 npr2基因 nprB蛋白 基因变异 身材矮小 Maroteaux型肢端肢中发育不全 特发性矮小
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穿越断裂带隧道变形机制及NPR支护数值模拟研究
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作者 曹振生 徐海斌 +2 位作者 虎晓敏 张光逵 刘珂源 《地下空间与工程学报》 北大核心 2025年第6期2122-2132,共11页
穿越断裂带的隧道在铁路工程、水利工程、公路工程较为常见,由穿越断层破碎带所诱发的工程地质灾害占我国隧道灾害总数的50%以上,保证穿断层带隧道的安全稳定是发展我国隧道工程的重中之重。以他白依隧道为工程背景,探究围岩在断层破碎... 穿越断裂带的隧道在铁路工程、水利工程、公路工程较为常见,由穿越断层破碎带所诱发的工程地质灾害占我国隧道灾害总数的50%以上,保证穿断层带隧道的安全稳定是发展我国隧道工程的重中之重。以他白依隧道为工程背景,探究围岩在断层破碎带影响下的有效支护措施。为解决他白依隧道软岩大变形问题,本文首先通过开展现场点荷载试验、地应力试验及室内矿物成分分析试验来探究形成大变形原因的主控因素,之后针对他白依隧道变形力学机制提出高预紧力长短NPR锚网支护方案,依据开挖补偿理论利用NPR锚索的高预紧力对隧道围岩进行应力补偿,并通过数值模拟与现场监测说明隧道在高预紧力长短NPR锚网支护方案下能够有效减少围岩在断层破碎带影响下产生的大变形。该研究成果可为穿越断层带的隧道支护提供参考。 展开更多
关键词 隧道工程 断层破碎带 变形力学机制 npr锚网支护 数值模拟
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Roof deformation of the Beishan Rock Carvings with negative Poisson's ratio anchor support under varied precipitation conditions 被引量:1
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作者 YANG Peixi TAO Zhigang +1 位作者 YANG Xiaojie LI Xiaodan 《Journal of Mountain Science》 2025年第8期3078-3091,共14页
Beishan Rock Carvings in Chongqing,a renowned cultural heritage site in China,flourished during the Tang and Song dynasties and are often referred to as the“Stone Carving Art Museum of the Tang and Song Dynasties.”C... Beishan Rock Carvings in Chongqing,a renowned cultural heritage site in China,flourished during the Tang and Song dynasties and are often referred to as the“Stone Carving Art Museum of the Tang and Song Dynasties.”Cave 168 is a key component of the Beishan Rock Carvings.At present,several through-going cracks have developed in the roof of Cave 168,severely compromising the structural stability of the grotto.The early internal steel plate supports have suffered severe corrosion and can no longer provide effective reinforcement.In addition,the presence of steel columns obstructs visitor access and negatively affects the viewing experience.A new reinforcement method is urgently needed.Therefore,studying the deformation patterns of the structure is of critical importance.This study analyzes the stratigraphic parameters and fracture distribution of Cave 168,considering key influencing factors such as rainfall,self-weight,and the overlying Quaternary soil.On-site monitoring and physical model experiments were conducted to evaluate the changes in roof crack width and displacement before and after reinforcement with negative Poisson's ratio(NPR)anchor cables.The results reveal that the roof of Cave 168 contains several through-going cracks and numerous microcracks,which serve as infiltration channels for surface water.These accelerate the softening of the mudstone and pose a significant threat to the cave's structural safety.During the experiment,the main change in the crack exhibited a“semi-archshaped”propagation pattern.In the first ten minutes,as the rock transitioned from dry to moist conditions,a slight crack closure was observed.As rainfall continued,crack propagation accelerated.After rainfall ceased,crack width remained stable over a short period.Under NPR anchor support,the influence of rainfall on roof settlement was effectively mitigated,ensuring the safety and stability of the roof.The NPR anchors successfully limited the roof settlement to within 0.3 mm and provided effective control over both total and differential settlement.These findings offer valuable insights into the application of NPR anchor cables in the conservation of grotto heritage structures. 展开更多
关键词 Grotto stability Physical model experiment RAINFALL npr anchor(cable) On-site monitoring
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Tuning negative thermal expansion in Sm_(0.85)Zn_(0.15)MnO_(3−δ)via synthesis optimization for enhancing the stability of heterostructured solid oxide fuel cell cathodes 被引量:1
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作者 Jakub Fudalewski Piotr Winiarz Kun Zheng 《International Journal of Minerals,Metallurgy and Materials》 2025年第11期2689-2698,共10页
Minimizing the thermal expansion coefficient(TEC)mismatch between the cathode and electrolyte in solid oxide fuel cells is crucial for achieving stable,durable operation and high performance.Recently,materials with ne... Minimizing the thermal expansion coefficient(TEC)mismatch between the cathode and electrolyte in solid oxide fuel cells is crucial for achieving stable,durable operation and high performance.Recently,materials with negative thermal expansion(NTE)have at-tracted significant attention as effective additives for tailoring the thermomechanical properties of electrodes and enhancing cell durability.In this work,for the first time,single-phase NTE perovskite Sm_(0.85)Zn_(0.15)MnO_(3−δ)(SZM15)was successfully synthesized via the sol-gel method,eliminating the unwanted ZnO phase typically observed in materials obtained through the conventional solid-state reaction route.The sol-gel approach proved highly advantageous,offering low cost,robustness,excellent chemical homogeneity,precise compositional control,and high phase purity.After optimization of synthesis parameters,a negative TEC of approximately−6.5×10^(−6)K^(−1)was achieved in the 400-850℃range.SZM15 was then incorporated as an additive(10wt%-50wt%)into a SmBa0.5Sr0.5CoCuO_(5+δ)(SBSCCO)cathode to tune the thermomechanical properties with a La_(0.8)Sr_(0.2)Ga_(0.8)Mg_(0.2)O_(3−δ)(LSGM)electrolyte,achieving a minimal TEC mismatch of only 1%.Notably,the SBSCCO+10wt%SZM15 composite cathode exhibited the lowest polarization resistance of 0.019Ω·cm^(2)at 900℃,showing approximately 70%lower than that of the pristine cathode.Excellent long-term stability after 100 h of operation was achieved.In addition,a high peak power density of 680 mW·cm^(−2)was achieved in a Ni-YSZ(yttria-stabilized zirconia)|YSZ|Ce_(0.9)Gd_(0.1)O_(2−δ)(GDC10)|SBSCCO+10wt%SZM15 anode-supported fuel cell at 850℃,highlighting the effectiveness of incorporating NTE materials as a promising strategy for regulating the thermomechanical properties and improving the long-term stability of intermediate temperature solid oxide fuel cells(IT-SOFCs). 展开更多
关键词 negative thermal expansion solid oxide fuel cell cathodes for solid oxide fuel cells sol-gel synthesis method
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NPR锚杆在青岛地铁暗挖车站主体工程应用的经济效益分析
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作者 张芹 朱孟安 +2 位作者 崔琪 张鹏 吴景福 《价值工程》 2025年第14期19-21,共3页
随着城市轨道交通的快速发展,地铁工程建设的技术创新成为提高工程质量和经济效益的关键。基于青岛地铁暗挖车站主体工程NPR锚杆的应用,分析NPR锚杆成本组成及主动支护方案的优势。对比NPR锚杆应用前后车站主体工程量变化,分析其工期、... 随着城市轨道交通的快速发展,地铁工程建设的技术创新成为提高工程质量和经济效益的关键。基于青岛地铁暗挖车站主体工程NPR锚杆的应用,分析NPR锚杆成本组成及主动支护方案的优势。对比NPR锚杆应用前后车站主体工程量变化,分析其工期、经济效益,为地铁工程建设技术选择和成本控制提供有价值的参考。 展开更多
关键词 地铁 暗挖车站 npr锚杆 经济效益
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Experimental study on the mechanical properties of NPR steel bars at high temperatures
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作者 ZHANG Jin XU Chuan-long +4 位作者 ZHU Chun XIA Min MA Zi-han LIU Chen ZHANG Xiang-yu 《Journal of Central South University》 2025年第4期1468-1480,共13页
Negative Poisson ratio(NPR)steel is a new material with high strength and toughness.This study conducted tensile tests at elevated temperatures to investigate the mechanical properties of NPR steel at high temperature... Negative Poisson ratio(NPR)steel is a new material with high strength and toughness.This study conducted tensile tests at elevated temperatures to investigate the mechanical properties of NPR steel at high temperatures.The stress−strain curve,ultimate strength,yield strength,modulus of elasticity,elongation after fracture,and percentage reduction of area of NPR steel bars were measured at 9 different temperatures ranging from 20 to 800℃.The experimental results indicate that high-temperature environments significantly affect the mechanical properties of NPR steel.However,compared to other types of steel,NPR steel exhibits better resistance to deformation.When the test temperature is below 700℃,NPR steel exhibits a ductile fracture characteristic,while at 800℃,it exhibits a brittle fracture characteristic.Finally,based on the experimental findings,a constitutive model suitable for NPR steel at high temperatures is proposed. 展开更多
关键词 npr steel bars high temperatures mechanical properties least squares method constitutive model
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Impacts and depositional behaviors of debris flows on natural boulder-negative Poisson's ratio anchor cable baffles
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作者 Feifei Zhao Manchao He +1 位作者 Qiru Sui Zhigang Tao 《Journal of Rock Mechanics and Geotechnical Engineering》 2025年第2期946-959,共14页
The impacts of natural boulders carried by debris flows pose serious risks to the safety and reliability of structures and buildings.Natural boulders can be highly random and unpredictable.Consequently,boulder control... The impacts of natural boulders carried by debris flows pose serious risks to the safety and reliability of structures and buildings.Natural boulders can be highly random and unpredictable.Consequently,boulder control during debris flows is crucial but difficult.Herein,an eco-friendly control system featuring anchoring natural boulders(NBs)with(negative Poisson's ratio)NPR anchor cables is proposed to form an NB-NPR baffle.A series of flume experiments are conducted to verify the effect of NB-NPR baffles on controlling debris flow impact.The deployment of NB-NPR baffles substantially influences the kinematic behavior of a debris flow,primarily in the form of changes in the depositional properties and impact intensities.The results show that the NB-NPR baffle matrix successfully controls boulder mobility and exhibits positive feedback on solid particle deposition.The NB-NPR baffle group exhibits a reduction in peak impact force ranging from 29%to 79%compared to that of the control group in the basic experiment.The NPR anchor cables play a significant role in the NB-NPR baffle by demonstrating particular characteristics,including consistent resistance,large deformation,and substantial energy absorption.The NB-NPR baffle innovatively utilizes the natural boulders in a debris flow gully by converting destructive boulders into constructive boulders.Overall,this research serves as a basis for future field experiments and applications. 展开更多
关键词 Debris flow Natural boulders npr anchor cable BAFFLE Depositional behavior Impact
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Scholl cyclization of[6]helicenes into negatively curved hexa[7]circulenes
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作者 Wenxiong Yu Chenyu Yang +1 位作者 Xian Feng Chengshuo Shen 《Chinese Chemical Letters》 2025年第11期295-300,共6页
The Scholl cyclization for creating seven-membered rings is of great importance in synthesizing negatively curved polycyclic aromatic compounds.In this study,we systematically report a methodical approach for converti... The Scholl cyclization for creating seven-membered rings is of great importance in synthesizing negatively curved polycyclic aromatic compounds.In this study,we systematically report a methodical approach for converting[6]helicenes into negatively curved hexa[7]circulene using Scholl cyclization.The reaction revealed that the electron-donating substituents on the helicene terminal rings of helicenes facilitate the cyclization process while electron-withdrawing substituents would impede the cyclization.This was supported by theoretical calculations on the reaction process focusing on the arenium cation pathways.Through the application of this Scholl cyclization,a series of negatively curved hexa[7]circulene derivatives were synthesized,showing highly curved and twisted geometries.Notably,2,15-substituted derivatives exhibited high conformational stability against racemization,thereby performing circularly polarized luminescence with|glum|up to 4×10^(-3). 展开更多
关键词 Scholl reaction HELICENE Circulene negative curvature CHIRALITY
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Nursing care of a patient with negative symptoms of schizophrenia who underwent tracheotomy:A case report
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作者 Jin-Yuan Li Xiao-En Liu +1 位作者 Wei Li Li-Na Wang 《World Journal of Clinical Cases》 2025年第25期112-119,共8页
BACKGROUND Patients with schizophrenia may lack awareness of the importance of posttracheotomy care due to the impact of their condition,often showing resistance or misunderstanding of care measures.When coupled with ... BACKGROUND Patients with schizophrenia may lack awareness of the importance of posttracheotomy care due to the impact of their condition,often showing resistance or misunderstanding of care measures.When coupled with the impact of negative symptoms and the risk of complications after tracheotomy,patients may experience emotional fluctuations,restlessness,anxiety,and hostile behaviors,which pose significant challenges to nursing work.CASE SUMMARY We have reported the case of an 87-year-old male patient who was admitted to the hospital because of negative symptoms of schizophrenia and who underwent tracheotomy for severe pneumonia.In this study,we have summarized the nursing experience of a patient with negative symptoms of schizophrenia who underwent tracheotomy.The key nursing strategies included proper tracheotomy care,the management of psychiatric symptoms,a thorough assessment and implementation of enteral and parenteral nutrition,effective skincare,infection prevention,and comprehensive mental care.Individualized nursing skills helped stabilize the patient’s condition,followed by isolation and observation in a psychiatric hospital.CONCLUSION Effective postoperative tracheostomy care in patients with schizophrenia necessitates a tailored,multidisciplinary approach that addresses their psychiatric,physical,and emotional needs to achieve optimal clinical outcomes. 展开更多
关键词 negative symptoms SCHIZOPHRENIA TRACHEOTOMY CARE Case report
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Effectiveness and safety of blonanserin monotherapy for firstepisode schizophrenia with and without prominent negative symptoms: A prospective study
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作者 Li-He Chen Qian Guo +7 位作者 Yao Hu Xiao-Hua Liu Hao Hu Hai-Ying Chen Cai-Ping Liu Hua-Fang Li Jin-Dong Chen Guan-Jun Li 《World Journal of Psychiatry》 2025年第5期230-240,共11页
BACKGROUND Blonanserin,a novel antipsychotic,has demonstrated efficacy in treating both positive and negative symptoms.However,limited research exists on its dose-dependent effectiveness and safety in patients with an... BACKGROUND Blonanserin,a novel antipsychotic,has demonstrated efficacy in treating both positive and negative symptoms.However,limited research exists on its dose-dependent effectiveness and safety in patients with and without prominent nega-tive symptoms(PNS).AIM To evaluate the effectiveness and safety of blonanserin monotherapy for first-episode schizophrenia in real-world clinical settings and to explore the efficacy and safety of different doses of blonanserin for patients with PNS and without PNS.METHODS A 12-week,multicenter,prospective post-marketing surveillance was conducted.In this study,we included patients with first-episode schizophrenia who received blonanserin monotherapy.Patients were divided into those with PNS and without PNS,based on the Brief Psychiatric Rating Scale(BPRS)negative symptoms subscale scores.Additionally,patients were labeled as high-dose and low-dose was evaluated through the incidence of adverse drug reactions(ADRs).RESULTS A total of 653 patients were included in the analysis,with 613 completing the study.The BPRS total score decreased significantly from 47.94±16.31 at baseline to 26.88±9.47 at 12 weeks(P<0.001).A significant interaction of PNS×dose×time was observed for BPRS total scores(F=3.47,P=0.040)and negative symptom subscale scores(F=6.76,P=0.002).In the PNS group,the high-dose group showed greater reductions in BPRS total scores(P=0.001)and negative symptom subscale scores(P=0.003)than the low-dose group in week 12.In the without PNS group,no significant difference was observed between the high-dose and low-dose groups at any visit.Most adverse reactions were mild or moderate,with extrapyramidal symptoms(9.3%)being most common;1.5%of patients gained≥7%body weight at 12 weeks.CONCLUSION Blonanserin effectively alleviated the clinical symptoms of first-episode schizophrenia with an acceptable safety profile.High-dose blonanserin is particularly beneficial for patients with PNS in the acute phase of first-episode schizophrenia.However,due to the limitation of ADR reporting the real world,the ADR incidence observed in this study may be underestimated. 展开更多
关键词 SCHIZOPHRENIA BLONANSERIN negative symptoms EFFECTIVENESS SAFETY DOSE
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Characterization of Negative Poisson's Ratio anchor cable forces in loess slopes
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作者 YU Xin LONG Jianhui TAO Zhigang 《Journal of Mountain Science》 2025年第10期3887-3900,共14页
In the realm of slope monitoring and reinforcement,traditional prestressing anchor cables are extensively used.However,these conventional methods often face limitations when applied to loess slopes,such as potential i... In the realm of slope monitoring and reinforcement,traditional prestressing anchor cables are extensively used.However,these conventional methods often face limitations when applied to loess slopes,such as potential issues with stress concentration and insufficient adaptability to the unique mechanical properties of loess,which may lead to challenges in ensuring long-term stability and effective reinforcement.Negative Poisson's ratio(NPR)anchor cables with constant resistance have emerged as a promising alternative,which can better match the engineering demands of loess slopes by providing more uniform stress distribution and adaptive deformation characteristics.The NPR cable's ability to maintain a constant resistance during deformation offers a distinct advantage over traditional methods as it can more effectively accommodate the complex and variable conditions of loess slopes.To investigate the anchoring performance of NPR cables in loess slope,the stress characteristics of NPR cable in loess medium were simulated and analysed by ABAQUS finite element software.First,static and general quasi-static analysis methods were used to simulate the NPR cable under static tensile conditions.The consistency of the simulated constant resistance deformation characteristics with experimental results found in the literature was verified.Second,the interaction model between the NPR cable coupled with the loess medium was established.Its constant resistance was calculated to be about 24.08%larger than that of NPR anchor cable while its plastic deformation was reduced by about 37.14%.The compressive stress on the contact surface between NPR cable and loess was concentrated near the free end of the sleeve,which indicated that the loess was prone to severe damage at the free end.The research results reveal the typical shear failure mechanism of NPR cable in loess medium,which provides an important theoretical basis for prevention of landslides and monitoring of loess slopes. 展开更多
关键词 Numerical analysis npr cable Loess medium Mechanical analysis Newton force monitoring LANDSLIDES
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