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Negative Coulomb drag between graphene quantum Hall edges
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作者 SONG Junwei GAN Qikang +4 位作者 ZHU Wang WATANABE Kenji TANIGUCHI Takashi YU Geliang WANG Lei 《物理学进展》 北大核心 2026年第1期1-12,共12页
Coulomb drag refers to the phenomenon in which a current driven through one conducting layer induces a voltage nearby,electrically isolated layer sorely through interlayer Coulomb interactions between charge carriers.... Coulomb drag refers to the phenomenon in which a current driven through one conducting layer induces a voltage nearby,electrically isolated layer sorely through interlayer Coulomb interactions between charge carriers.It has been extensively studied in various systems,including parallel nanowires,double quantum wells,and double-layer graphene.Here,we report the observation of Coulomb drag in a novel system consisting of two graphene layers separated laterally by a 30 nm gap within the material plane,exhibiting behavior distinct from that in vertical graphene heterostructures.Our experiments reveal pronounced negative drag resistances under an out-of-plane magnetic field at the quantum Hall edges,reaching a maximum when the carrier densities in both graphene layers are tuned to the charge neutrality point via gate voltages.Our work establish two separate and spatially closed quantum Hall edge modes as a new platform to explore electronic interaction physics between one dimensional systems. 展开更多
关键词 negative Coulomb drag quantum Hall edges van der Waals heterostructures
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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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(1-x)NiCo_(0.2)Mn_(1.8)O_(4)-xBaBiO_(3)体系NTC复相陶瓷的结构与电性能调控
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作者 万轲 陈红硕 +1 位作者 毕文平 周毅 《中国陶瓷》 北大核心 2025年第10期18-25,共8页
采用两步法制备了(1-x)NiCo_(0.2)Mn_(1.8)O_(4)-xBaBiO_(3)(x=0.1、0.2、0.3、0.4)系列负温度系数(Negative Temperature Coefficient,NTC)复相陶瓷材料。系统研究了BaBiO_(3)(BB)含量对NiCo_(0.2)Mn_(1.8)O_(4)(NCM)基复相陶瓷的相结... 采用两步法制备了(1-x)NiCo_(0.2)Mn_(1.8)O_(4)-xBaBiO_(3)(x=0.1、0.2、0.3、0.4)系列负温度系数(Negative Temperature Coefficient,NTC)复相陶瓷材料。系统研究了BaBiO_(3)(BB)含量对NiCo_(0.2)Mn_(1.8)O_(4)(NCM)基复相陶瓷的相结构、显微结构及电学性能的影响。结果表明,当x=0.1时,复相陶瓷内部均为细小均匀的三棱锥结构的尖晶石NiCo_(0.2)Mn_(1.8)O_(4)相。当x=0.2时,钙钛矿BaBiO_(3)相开始增多,且尖晶石晶粒开始长大、棱边开始变得圆润。当x达到0.3及以上时,内部晶粒继续长大,而且晶界明显增宽和变得模糊,呈现液相烧结特征,此外有第二相BaMnO_(3)开始生成并增多。阻抗分析表明,复相陶瓷的电阻主要决定于内部的晶界电阻。电阻分析表明室温电阻率ρ_(25℃)、温度敏感常数B、电导活化能E_(a)均呈现出随着BaBiO_(3)含量先降低后升高的趋势,且极小值出现在x=0.2时。该体系复合陶瓷的B值、ρ_(25℃)和E_(a)分别在4151~4374 K、4930~26206Ω·cm和0.357~0.376 eV的范围可调,拓宽了尖晶石体系热敏陶瓷的应用范围。 展开更多
关键词 复相陶瓷 电性能 ntc热敏电阻 阻抗谱 渗流理论
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磁控溅射MoSi_(2)薄膜工艺及其对NTC响应的影响
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作者 刘吉华 余江涛 +4 位作者 俞茹昕 孔雯雯 卜小龙 魏赞 窦盈莹 《五邑大学学报(自然科学版)》 2025年第2期15-23,共9页
硅化钼(MoSi_(2))熔点高,导电导热性好,耐高温氧化,工艺兼容性好,且在中长波红外波段呈现出强吸收特性,在红外热探测领域有重要的应用价值.本文先运用直流磁控溅射法沉积MoSi_(2)薄膜,通过梯度调整生长温度、退火温度以及生长时间,制得... 硅化钼(MoSi_(2))熔点高,导电导热性好,耐高温氧化,工艺兼容性好,且在中长波红外波段呈现出强吸收特性,在红外热探测领域有重要的应用价值.本文先运用直流磁控溅射法沉积MoSi_(2)薄膜,通过梯度调整生长温度、退火温度以及生长时间,制得一系列MoSi_(2)薄膜.借助XRD、XPS、SEM、FT-IR等多种分析测试手段,对薄膜的化学组成、晶体结构、薄膜厚度及红外吸收性能展开表征.最终,将优选的MoSi_(2)薄膜沉积至负温度系数(NTC)热敏电阻型红外探测单元表面,以优化器件的红外探测性能.结果显示,在生长温度为250℃、退火温度为600℃的条件下,生长时间为20 min的MoSi_(2)薄膜对中长波红外的反射显著降低,器件的红外探测性能得以显著提升.沉积有MoSi_(2)薄膜的探测单元,对黑体辐射红外光源的平均响应率提高了17.6 V/W,且维持了较快的响应速度,探测器的响应时间为52.7 ms. 展开更多
关键词 MoSi_(2)薄膜 磁控溅射 ntc热敏电阻 红外探测 黑体响应率
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Nb^(5+)掺杂对Ni-Mn-O基NTC热敏材料特性影响的研究
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作者 程飞鹏 辜丽欢 向艳 《电子元件与材料》 北大核心 2025年第5期518-523,共6页
以传统固相反应法制备了Ni_(0.75-x)Mn_(2.25)Nb_(x)O_(4)(x=0,0.15,0.25,0.35)NTC热敏电阻陶瓷。通过X射线衍射(XRD)、扫描电子显微镜(SEM)及电学性能测试,深入探究了Nb5+掺杂对Ni_(0.75-x)Mn_(2.25)Nb_(x)O_(4)材料的相组成、微观形... 以传统固相反应法制备了Ni_(0.75-x)Mn_(2.25)Nb_(x)O_(4)(x=0,0.15,0.25,0.35)NTC热敏电阻陶瓷。通过X射线衍射(XRD)、扫描电子显微镜(SEM)及电学性能测试,深入探究了Nb5+掺杂对Ni_(0.75-x)Mn_(2.25)Nb_(x)O_(4)材料的相组成、微观形貌及阻温特性的影响机制。实验结果表明:当x≤0.15时,材料保持单一的立方尖晶石结构;当x≥0.25时,材料中出现尖晶石相(NiMn_(2)O_(4))和MnNb_(2)O_(6)、Mn_(3)O_(4)第二相共存现象,且立方尖晶石结构的衍射峰强度大幅降低,第二相关联峰强度增加。当x≤0.15时,晶粒尺寸明显增加,多面体棱角特征明晰;随着掺杂量的增加,形貌明显不同于单相,晶界模糊。电性能测试显示,随着Nb^(5+)掺杂量的增加,Ni_(0.75-x)Mn_(2.25)Nb_(x)O_(4)材料的电阻率呈先减后增趋势,x=0.15时,材料的B25/50=4160 K,电阻率最低(ρ=7786.61Ω·cm),呈现出“高B低阻”特性,实现了温度敏感性与低电阻特性的协同优化。本工作揭示了Nb^(5+)掺杂量通过调控尖晶石相纯度与晶粒生长行为影响载离子传输的微观机制,为高性能尖晶石型NTC热敏陶瓷的组分设计与性能优化提供了重要实验依据。 展开更多
关键词 ntc热敏电阻 尖晶石结构 Ni-Mn-O Nb^(5+)掺杂
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Elderly care needs and factors influencing negative emotions among first-generation only child parents in a Chinese city 被引量:1
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作者 Rui Dong Xiu-Xia Wang Ling-Juan Zhang 《World Journal of Psychiatry》 2025年第5期155-163,共9页
BACKGROUND China has recently encountered severe challenges associated with population aging.Parents of first-generation only children face significant challenges regarding elderly care needs and the associated negati... BACKGROUND China has recently encountered severe challenges associated with population aging.Parents of first-generation only children face significant challenges regarding elderly care needs and the associated negative emotions.AIM To analyze the elderly care needs of first-generation only child parents in China and identify factors that influence negative emotions.METHODS This study used a cross-sectional design.Convenience sampling was used to select 1580 elderly individuals who met the inclusion criteria in a Chinese city between June and September 2022.A questionnaire was administered to collect general information about participants.Depression and anxiety were assessed using the patient health questionnaire-9 and generalized anxiety disorder-7 scale,respectively.A logistic regression analysis was performed to evaluate the relevant correlations.RESULTS Among 1580 first-generation only child parents,1120(70.89%)preferred family based care,324(20.51%)opted for community care,and 136(8.61%)chose institutional care,with 460(29.11%)reporting negative emotions.Significant differences in the distribution of negative emotions among only child parents were observed based on age,marital status,living conditions,disability,type of chronic disease,frailty status,and family support(P<0.05).The regression analysis indicated that disability,type of chronic disease,living environment,frailty status,and level of family support were independent risk factors for negative emotions among parents with only children(P<0.05).CONCLUSION Elderly care for parents of only children is primarily family-based.Independent risk factors for negative emotions in this group include disability,chronic disease type,and living environment. 展开更多
关键词 AGING First generation Only child Elderly care needs negative emotions Influencing factors
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Important role of tumor deposits and negative lymph nodes in prognosis of N1c colorectal cancer patients 被引量:1
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作者 Zhi-Gang Sun Shao-Xuan Chen +11 位作者 Bai-Long Sun Da-Kui Zhang Ding-Rong Zhong Tong-Yin Zhang Yu-Wan Hu Zi-Han Han Wen-Xiao Wu Zhi-Yong Hou Li Yao Ya-Jun Zhang Hong-Liang Sun Jian-Zheng Jie 《World Journal of Gastroenterology》 2025年第31期52-62,共11页
BACKGROUND The number of tumor deposits(TDs)does not play a part in the current tumor node metastasis staging.Negative lymph node(NLN)status is associated with the prognosis of colorectal cancer(CRC),but its clear rol... BACKGROUND The number of tumor deposits(TDs)does not play a part in the current tumor node metastasis staging.Negative lymph node(NLN)status is associated with the prognosis of colorectal cancer(CRC),but its clear role in N1c stage remains to be defined.AIM To evaluate the combination of TDs and NLNs as potential prognostic indicators in N1c CRC.METHODS We retrospectively identified 107 consecutive patients who had N1c CRC radically resected at China-Japan Friendship Hospital.The combination of TDs and NLNs was calculated by the formula NLNTD=NLN/(TD+1).Cutoff values of NLNs and NLNTD were determined using the R package“survminer”.Disease-free survival(DFS),overall survival(OS)and cancer-specific survival(CSS)were determined using the Kaplan-Meier method to assess the impact of NLNTD on prognosis.Results were compared using the log-rank test.RESULTS The median follow-up time was 63.17(45.33-81.37)months for DFS,with 33.64%(36/107)of patients experiencing recurrence during follow-up.Five-year DFS was 66.0%(57.3%-76.0%).There was no significant difference in prognosis between patients with>12 and≤12 NLNs(P=0.058)for DFS.Similar results were seen according to the number of TDs.The definition of NLNTD=NLN/(TD+1)with a cutoff value of 6 divided patients into two groups with different DFS(P=0.005).Five-year DFS for patients with NLNTD>6 was 73.5%(63.6%-85.0%),compared with 50.0%(35.7%-70.0%)for those with NLNTD≤6.These two groups had different prognosis without perineural invasion(P=0.012)or lymphovascular invasion(P=0.002)even neither(P=0.053).Similar results were seen for OS and CSS.CONCLUSION NLNTD could serve as important prognostic factor for outcomes in N1c CRC patients.These patients could be stratified for prognosis through NLNTD and the high-risk should be given more attention during treatment. 展开更多
关键词 Colorectal cancer N1c stage negative lymph node Tumor deposits PROGNOSIS
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Achieving negative thermal expansion over an extended temperature range in rare-earth-modified Pb TiO_(3)-based perovskites 被引量:1
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作者 Zhao Pan Meng-Qi Ye +12 位作者 Yan Suo Feng-Yi Zhou Duo Wang Jin Liu Xu-Bin Ye Jie Zhang Mao-Cai Pi Wei-Hao Li Chao Chen Nian-Peng Lu Shogo Kawaguchi Yao Shen You-Wen Long 《Rare Metals》 2025年第9期6494-6502,共9页
Negative thermal expansion(NTE)is a notable physical property where a material’s volume decreases instead of increasing when heated.The identification of NTE materials is crucial for thermal expansion control enginee... Negative thermal expansion(NTE)is a notable physical property where a material’s volume decreases instead of increasing when heated.The identification of NTE materials is crucial for thermal expansion control engineering.Most NTE materials exhibit NTE only within a narrow temperature range,restricting their applications.Achieving NTE across a broad temperature range remains a significant challenge.This study developed a novel PbTiO_(3)-based system,(1-x)PbTiO_(3–x)BiLuO_(3),incorporating rare-earth elements,using a distinctive high-pressure and high-temperature synthesis technique.We achieved NTE across a broad temperature range by coupling lattice(c/a)with ferroelectric order parameters.The incorporation of BiLuO_(3)resulted in distinctive ferroelectric characteristics,including increased tetragonality,spontaneous polarization,and NTE over a broad temperature range.NTE over an extended temperature range has been achieved in 0.95PbTiO_(3)–0.05BiLuO_(3)(■=−1.7×10^(–5)K^(−1),300–840 K)and 0.90PbTiO_(3)–0.10BiLuO_(3)(■=−1.4×10^(–5)K^(−1),300–860 K),compared to pristine PbTiO_(3)(■=−1.99×10^(–5)K^(−1),300–763 K).The improved tetragonalities and broader NTE temperature range result from the strong hybridization of Pb/Bi–O and Ti/Lu–O atoms,as demonstrated by combined experimental and theoretical analyses,including high-energy synchrotron X-ray diffraction,Raman spectroscopy,and density functional theory calculations.This study introduces a novel example of NTE over a broad temperature range,highlighting its potential as a high-performance thermal expansion compensator.Additionally,it presents an effective method for incorporating rare-earth elements to achieve NTE in PbTiO_(3)-based perovskites across a wide temperature range. 展开更多
关键词 negative thermal expansion High-pressure and high-temperature synthesis Density functional theory
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Efficacy and safety of negative pressure wound therapy for the treatment of diabetic foot ulcers: A meta-analysis 被引量:1
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作者 Yun-Xiang Deng Xiao-Chuan Wang +2 位作者 Zhen-Yu Xia Meng-Ya Wan Du-Yin Jiang 《World Journal of Diabetes》 2025年第6期330-339,共10页
BACKGROUND Diabetic foot ulcers(DFUs)are a significant challenge in diabetic care,and the efficacy of negative pressure wound therapy(NPWT)in treating them remains a subject of continuous investigation.AIM To provide ... BACKGROUND Diabetic foot ulcers(DFUs)are a significant challenge in diabetic care,and the efficacy of negative pressure wound therapy(NPWT)in treating them remains a subject of continuous investigation.AIM To provide a comprehensive meta-analysis of the role of NPWT in the manage-ment of DFUs.METHODS A systematic review was performed based on Preferred Reporting Items for Sys-tematic Reviews and Meta-Analyses guidelines,searching databases like PubMed,Embase,Web of Science,and the Cochrane Library.Randomized clinical trials(RCTs)were included to compare NPWT to other dressings for DFUs.Outcomes measured were wound healing time and rate,granulation tissue formation time,amputation rate,and adverse events.Study quality was evaluated using Coch-rane's risk of bias tool.Analyses utilizedχ2,I2,fixed or random-effects models via Stata v17.RESULTS Of the 1101 identified articles,9 RCTs were selected for meta-analysis.Studies spanned from 2005 to 2020 and originated from countries including the United States,Chile,Pakistan,Italy,India,and Germany.Meta-analysis demonstrated a significant improvement in wound healing rate[risk ratio(RR)=1.46,95%CI:1.22-1.76,P<0.01]and a reduction in amputation rate(RR=0.69,95%CI:0.50-0.96,P=0.006)with NPWT.Furthermore,the time for granulation tissue formation was significantly reduced by an average of 19.54 days.However,the incidence of adverse events did not significantly differ between NPWT and control treatments.CONCLUSION NPWT significantly improves wound healing rates and reduces amputation rates in DFUs.It also hastens the formation of granulation tissue.However,the therapy does not significantly alter the risk of adverse events compared to alternate treatments. 展开更多
关键词 negative pressure wound therapy Diabetic foot ulcer Wound healing AMPUTATION Adverse events META-ANALYSIS
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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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家电用NTC热敏电阻高温迟滞效应对B值影响的分析与研究
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作者 黄至焕 刘玉玲 +1 位作者 陈国正 陈灿坤 《日用电器》 2025年第6期24-27,33,共5页
NTC热敏电阻因其高灵敏度和快速响应特性,在电磁灶、电饭煲等电热类家电中广泛应用。然而在高温段,其电阻-温度(R-T)特性与基于材料常数B值拟合的理论值存在显著偏差。本文通过定量分析和成因探讨,揭示了高温下迟滞效应的成因,包括晶格... NTC热敏电阻因其高灵敏度和快速响应特性,在电磁灶、电饭煲等电热类家电中广泛应用。然而在高温段,其电阻-温度(R-T)特性与基于材料常数B值拟合的理论值存在显著偏差。本文通过定量分析和成因探讨,揭示了高温下迟滞效应的成因,包括晶格畸变和离子迁移等微观结构变化。结果表明,迟滞效应对B值的预测精度有显著影响,且这种影响随温度升高而加剧。为此,本文提出了优化的固定电阻替换策略,以减少迟滞效应的影响,提高NTC热敏电阻测量的准确性。本研究揭示了高温迟滞效应对B值预测精度的影响,为家电安全检测标准的完善提供了理论支持,并为优化NTC热敏电阻的评估体系和检测方法提供了方向。 展开更多
关键词 家电检测 ntc热敏电阻 材料常数B值 迟滞效应
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钴酸镧NTC热敏陶瓷材料的制备及其性能研究
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作者 葛中昆 韩文康 +5 位作者 赵金富 韩天祥 李志远 李玉成 汪澎洋 王吉如 《硬质合金》 2025年第5期15-24,共10页
LaCoO_(3)陶瓷具有钙钛矿结构,在常温区间内具有稳定的NTC效应,但是纯LaCoO_(3)材料的电阻较小,导致其NTC效应变化不显著。本文通过在LaCoO_(3)材料中掺杂不同比例的Cr_(2)O_(3)、Y_(2)O_(3)、Al_(2)O_(3)粉末,研究了不同粉末、不同掺... LaCoO_(3)陶瓷具有钙钛矿结构,在常温区间内具有稳定的NTC效应,但是纯LaCoO_(3)材料的电阻较小,导致其NTC效应变化不显著。本文通过在LaCoO_(3)材料中掺杂不同比例的Cr_(2)O_(3)、Y_(2)O_(3)、Al_(2)O_(3)粉末,研究了不同粉末、不同掺杂比例下,LaCoO_(3)物相的转化、晶体结构的改变,以及导电原理、电学性质的变化,制备出一系列具有显著NTC效应的陶瓷材料,可以作为测温模块的传感器材料,应用于刀具温度测控领域。 展开更多
关键词 钴酸镧 ntc陶瓷 掺杂改性 阻值分析 相结构
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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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提高NTC传感器信号抗干扰能力的策略
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作者 孔晓刚 杨晓平 +1 位作者 史艳博 林雪冰 《数字技术与应用》 2025年第6期28-30,共3页
本文针对负温度系数(NTC)传感器在应用中易受干扰的问题展开探讨,分析了传统电路拓扑结构的不足,并提出了优化方案;探讨了接地与电源设计对信号干扰的影响,并提出了改进措施;介绍了采用中位值滤波算法消除信号干扰的方法。本文旨在为提... 本文针对负温度系数(NTC)传感器在应用中易受干扰的问题展开探讨,分析了传统电路拓扑结构的不足,并提出了优化方案;探讨了接地与电源设计对信号干扰的影响,并提出了改进措施;介绍了采用中位值滤波算法消除信号干扰的方法。本文旨在为提升NTC传感器在复杂环境中的性能提供理论支持和实践指导。 展开更多
关键词 ntc传感器 优化方案 信号抗干扰 接地设计
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Mechanical manipulation of the transient negative capacitance effect in resistor-ferroelectric capacitor circuit
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作者 Qian He Weijin Chen +1 位作者 Xin Luo Yue Zheng 《Acta Mechanica Sinica》 2025年第2期237-246,共10页
Transient negative capacitance(NC),as an available dynamic charge effect achieved in resistor-ferroelectric capacitor(R-FEC)circuits,has triggered a series of theoretical and experimental works focusing on its physica... Transient negative capacitance(NC),as an available dynamic charge effect achieved in resistor-ferroelectric capacitor(R-FEC)circuits,has triggered a series of theoretical and experimental works focusing on its physical mechanism and device application.Here,we analytically derived the effects of different mechanical conditions on the transient NC behaviors in the R-FEC circuit based on the phenomenological model.It shows that the ferroelectric capacitor can exhibit either NC(i.e.,“single NC”and“double NC”)or positive capacitance,depending on the mechanical condition and temperature.Further numerical calculations show that the voltage drop caused by NC can be effectively controlled by temperature,applied stress,or strain.The relationship between NC voltage drop and system configurations including external resistance,dynamical coefficient of polarization,and input voltage are presented,showing diverse strategies to manipulate the NC effect.These results provide theoretical guidelines for rational design and efficient control of NC-related electronic devices. 展开更多
关键词 FERROELECTRIC Transient negative capacitance Mechanical manipulation
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Study on the Influence of Negative Transfer of Mother Tongue on Junior High School Students’ English Writing and Its Coping Strategies
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作者 WANG Zhao-xi JIN Ming-hao 《Journal of Literature and Art Studies》 2025年第3期189-197,共9页
Referring to the questionnaire survey and semi-structured interview,this paper explores the negative transfer of mother tongue in junior high school English writing and analyzes the existing problems.The results show ... Referring to the questionnaire survey and semi-structured interview,this paper explores the negative transfer of mother tongue in junior high school English writing and analyzes the existing problems.The results show that the negative transfer of mother tongue has a significant impact on junior high school students’English writing.The main errors are found at four levels:morphological level,lexical level,syntactic level and textual level.In order to deal with the errors caused by the negative transfer of mother tongue in students’English writing,it is suggested that teachers create an English language environment for students as far as possible and help students form English thinking,use contrastive analysis teaching strategies,making a comparison between English and Chinese expressions and cultural differences and pay attention to the training of students’basic knowledge of English to help students improve their English writing ability. 展开更多
关键词 mother tongue negative transfer English writing
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Caerulomycin A disrupts glucose metabolism and triggers ER stress-induced apoptosis in triple-negative breast cancer cells
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作者 Ye Zhang Shanshan Su +4 位作者 Xiaoyu Xu Zhixian He Yiyan Zhou Xiangrong Lu Aiqin Jiang 《Chinese Journal of Natural Medicines》 2025年第9期1080-1091,共12页
Triple-negative breast cancer(TNBC)represents an aggressive breast cancer subtype with poor prognosis and limited targeted treatment options.This investigation examined the anticancer potential of Caerulomycin A(Cae A... Triple-negative breast cancer(TNBC)represents an aggressive breast cancer subtype with poor prognosis and limited targeted treatment options.This investigation examined the anticancer potential of Caerulomycin A(Cae A),a natural compound derived from marine actinomycetes,against TNBC.Cae A demonstrated selective inhibition of viability and proliferation in TNBC cell lines,including 4T1,MDA-MB-231,and MDA-MB-468,through apoptosis induction.Mechanistic analyses revealed that the compound induced sustained endoplasmic reticulum(ER)stress and subsequent upregulation of C/EBP homologous protein(CHOP)expression,resulting in mitochondrial damage-mediated apoptosis.Inhibition of ER stress or CHOP expression knockdown reversed mitochondrial damage and apoptosis,highlighting the essential role of ER stress and CHOP in Cae A's anti-tumor mechanism.Both oxygen consumption rate(OCR)and extracellular acidification rate(ECAR)decreased in TNBC cells following Cae A treatment,indicating reduced mitochondrial respiratory and glycolytic capacities.This diminished energy metabolism potentially triggers ER stress and subsequent apoptosis.Furthermore,Cae A exhibited significant anti-tumor effects in the 4T1 tumor model in vivo without apparent toxicity.The compound also effectively inhibited human TNBC organoid growth.These results indicate that Cae A may serve as a potential therapeutic agent for TNBC,with its efficacy likely mediated through the disruption of glucose metabolism and the induction of ER stress-associated apoptosis. 展开更多
关键词 Triple negative breast cancer Caerulomycin A Glucose metabolism CHOP APOPTOSIS
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NTC训练对青年排球运动员下肢爆发力影响的实证研究
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作者 张浩博 王宇佳 《体育风尚》 2025年第8期155-157,共3页
研究目的:探索NTC训练是否能够提升青年排球运动员下肢爆发力。实验结果:实验前,两组受试者各项指标均符合正态分布,通过对两组受试者各项指标分析对比无显著性差异(P>0.05)。实验后,两组受试者各项指标均有提升,在组间对比中对照组... 研究目的:探索NTC训练是否能够提升青年排球运动员下肢爆发力。实验结果:实验前,两组受试者各项指标均符合正态分布,通过对两组受试者各项指标分析对比无显著性差异(P>0.05)。实验后,两组受试者各项指标均有提升,在组间对比中对照组纵向爆发力测试指标优于实验组(P<0.05);实验组横向爆发力测试指标优于对照组,其中六边形障碍跳指标具有非常显著性差异(P<0.01),半米字移动具有显著差异(P<0.05)。主要结论:实验验证了假设H1,证明了NTC训练与青年排球运动员下肢爆发力的提升具有相关性。 展开更多
关键词 体能训练 ntc训练 排球 下肢爆发力
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